examples/rabbitmq/vendor/phpseclib/phpseclib/LICENSE

+Copyright (c) 2011-2019 TerraFrost and other contributors
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
\ No newline at end of file

examples/rabbitmq/vendor/phpseclib/phpseclib/README.md

+# phpseclib - PHP Secure Communications Library
+
+[![CI Status](https://github.com/phpseclib/phpseclib/actions/workflows/ci.yml/badge.svg?branch=3.0&event=push "CI Status")](https://github.com/phpseclib/phpseclib)
+
+## Supporting phpseclib
+
+- [Become a backer or sponsor on Patreon](https://www.patreon.com/phpseclib)
+- [One-time donation via PayPal or crypto-currencies](http://sourceforge.net/donate/index.php?group_id=198487)
+- [Subscribe to Tidelift](https://tidelift.com/subscription/pkg/packagist-phpseclib-phpseclib?utm_source=packagist-phpseclib-phpseclib&utm_medium=referral&utm_campaign=readme)
+
+## Introduction
+
+MIT-licensed pure-PHP implementations of the following:
+
+SSH-2, SFTP, X.509, an arbitrary-precision integer arithmetic library, Ed25519 / Ed449 / Curve25519 / Curve449, ECDSA / ECDH (with support for 66 curves), RSA (PKCS#1 v2.2 compliant), DSA / DH, DES / 3DES / RC4 / Rijndael / AES / Blowfish / Twofish / Salsa20 / ChaCha20, GCM / Poly1305
+
+* [Browse Git](https://github.com/phpseclib/phpseclib)
+
+## Documentation
+
+* [Documentation / Manual](https://phpseclib.com/)
+* [API Documentation](https://api.phpseclib.com/3.0/) (generated by Doctum)
+
+## Branches
+
+### master
+
+* Development Branch
+* Unstable API
+* Do not use in production
+
+### 3.0
+
+* Long term support (LTS) release
+* Major expansion of cryptographic primitives
+* Minimum PHP version: 5.6.1
+* PSR-4 autoloading with namespace rooted at `\phpseclib3`
+* Install via Composer: `composer require phpseclib/phpseclib:~3.0`
+
+### 2.0
+
+* Long term support (LTS) release
+* Modernized version of 1.0
+* Minimum PHP version: 5.3.3
+* PSR-4 autoloading with namespace rooted at `\phpseclib`
+* Install via Composer: `composer require phpseclib/phpseclib:~2.0`
+
+### 1.0
+
+* Long term support (LTS) release
+* PHP4 compatible
+* Composer compatible (PSR-0 autoloading)
+* Install using Composer: `composer require phpseclib/phpseclib:~1.0`
+* Install using PEAR: See [phpseclib PEAR Channel Documentation](http://phpseclib.sourceforge.net/pear.htm)
+* [Download 1.0.20 as ZIP](http://sourceforge.net/projects/phpseclib/files/phpseclib1.0.20.zip/download)
+
+## Security contact information
+
+To report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.
+
+## Support
+
+Need Support?
+
+* [Checkout Questions and Answers on Stack Overflow](http://stackoverflow.com/questions/tagged/phpseclib)
+* [Create a Support Ticket on GitHub](https://github.com/phpseclib/phpseclib/issues/new)
+* [Browse the Support Forum](http://www.frostjedi.com/phpbb/viewforum.php?f=46) (no longer in use)
+
+## Special Thanks
+
+Special Thanks to our $50+ sponsors!:
+
+- Allan Simon
+- [ChargeOver](https://chargeover.com/)
+
+## Contributing
+
+1. Fork the Project
+
+2. Ensure you have Composer installed (see [Composer Download Instructions](https://getcomposer.org/download/))
+
+3. Install Development Dependencies
+    ```sh
+    composer install
+    ```
+
+4. Create a Feature Branch
+
+5. Run continuous integration checks:
+   ```sh
+   composer global require php:^8.1 squizlabs/php_codesniffer friendsofphp/php-cs-fixer vimeo/psalm
+   phpcs --standard=build/php_codesniffer.xml
+   php-cs-fixer fix --config=build/php-cs-fixer.php --diff --dry-run --using-cache=no
+   psalm --config=build/psalm.xml --no-cache --long-progress --report-show-info=false --output-format=text
+   vendor/bin/phpunit --verbose --configuration tests/phpunit.xml
+   ```
+   
+6. Send us a Pull Request

examples/rabbitmq/vendor/phpseclib/phpseclib/composer.json

+{
+    "name": "phpseclib/phpseclib",
+    "type": "library",
+    "description": "PHP Secure Communications Library - Pure-PHP implementations of RSA, AES, SSH2, SFTP, X.509 etc.",
+    "keywords": [
+        "security",
+        "crypto",
+        "cryptography",
+        "encryption",
+        "signature",
+        "signing",
+        "rsa",
+        "aes",
+        "blowfish",
+        "twofish",
+        "ssh",
+        "sftp",
+        "x509",
+        "x.509",
+        "asn1",
+        "asn.1",
+        "BigInteger"
+        ],
+    "homepage": "http://phpseclib.sourceforge.net",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Jim Wigginton",
+            "email": "terrafrost@php.net",
+            "role": "Lead Developer"
+        },
+        {
+            "name": "Patrick Monnerat",
+            "email": "pm@datasphere.ch",
+            "role": "Developer"
+        },
+        {
+            "name": "Andreas Fischer",
+            "email": "bantu@phpbb.com",
+            "role": "Developer"
+        },
+        {
+            "name": "Hans-Jürgen Petrich",
+            "email": "petrich@tronic-media.com",
+            "role": "Developer"
+        },
+        {
+            "name": "Graham Campbell",
+            "email": "graham@alt-three.com",
+            "role": "Developer"
+        }
+    ],
+    "require": {
+        "php": ">=5.6.1",
+        "paragonie/constant_time_encoding": "^1|^2",
+        "paragonie/random_compat": "^1.4|^2.0|^9.99.99"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "*"
+    },
+    "suggest": {
+        "ext-libsodium": "SSH2/SFTP can make use of some algorithms provided by the libsodium-php extension.",
+        "ext-openssl": "Install the OpenSSL extension in order to speed up a wide variety of cryptographic operations.",
+        "ext-mcrypt": "Install the Mcrypt extension in order to speed up a few other cryptographic operations.",
+        "ext-gmp": "Install the GMP (GNU Multiple Precision) extension in order to speed up arbitrary precision integer arithmetic operations.",
+        "ext-dom": "Install the DOM extension to load XML formatted public keys."
+    },
+    "autoload": {
+        "files": [
+            "phpseclib/bootstrap.php"
+        ],
+        "psr-4": {
+            "phpseclib3\\": "phpseclib/"
+        }
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "phpseclib3\\Tests\\": "tests/"
+        }
+    },
+    "config": {
+        "sort-packages": true
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Common/Functions/Strings.php

+<?php
+
+/**
+ * Common String Functions
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2016 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Common\Functions;
+
+use ParagonIE\ConstantTime\Base64;
+use ParagonIE\ConstantTime\Base64UrlSafe;
+use ParagonIE\ConstantTime\Hex;
+use phpseclib3\Math\BigInteger;
+use phpseclib3\Math\Common\FiniteField;
+
+/**
+ * Common String Functions
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class Strings
+{
+    /**
+     * String Shift
+     *
+     * Inspired by array_shift
+     *
+     * @param string $string
+     * @param int $index
+     * @return string
+     */
+    public static function shift(&$string, $index = 1)
+    {
+        $substr = substr($string, 0, $index);
+        $string = substr($string, $index);
+        return $substr;
+    }
+
+    /**
+     * String Pop
+     *
+     * Inspired by array_pop
+     *
+     * @param string $string
+     * @param int $index
+     * @return string
+     */
+    public static function pop(&$string, $index = 1)
+    {
+        $substr = substr($string, -$index);
+        $string = substr($string, 0, -$index);
+        return $substr;
+    }
+
+    /**
+     * Parse SSH2-style string
+     *
+     * Returns either an array or a boolean if $data is malformed.
+     *
+     * Valid characters for $format are as follows:
+     *
+     * C = byte
+     * b = boolean (true/false)
+     * N = uint32
+     * Q = uint64
+     * s = string
+     * i = mpint
+     * L = name-list
+     *
+     * uint64 is not supported.
+     *
+     * @param string $format
+     * @param string $data
+     * @return mixed
+     */
+    public static function unpackSSH2($format, &$data)
+    {
+        $format = self::formatPack($format);
+        $result = [];
+        for ($i = 0; $i < strlen($format); $i++) {
+            switch ($format[$i]) {
+                case 'C':
+                case 'b':
+                    if (!strlen($data)) {
+                        throw new \LengthException('At least one byte needs to be present for successful C / b decodes');
+                    }
+                    break;
+                case 'N':
+                case 'i':
+                case 's':
+                case 'L':
+                    if (strlen($data) < 4) {
+                        throw new \LengthException('At least four byte needs to be present for successful N / i / s / L decodes');
+                    }
+                    break;
+                case 'Q':
+                    if (strlen($data) < 8) {
+                        throw new \LengthException('At least eight byte needs to be present for successful N / i / s / L decodes');
+                    }
+                    break;
+
+                default:
+                    throw new \InvalidArgumentException('$format contains an invalid character');
+            }
+            switch ($format[$i]) {
+                case 'C':
+                    $result[] = ord(self::shift($data));
+                    continue 2;
+                case 'b':
+                    $result[] = ord(self::shift($data)) != 0;
+                    continue 2;
+                case 'N':
+                    list(, $temp) = unpack('N', self::shift($data, 4));
+                    $result[] = $temp;
+                    continue 2;
+                case 'Q':
+                    // pack() added support for Q in PHP 5.6.3 and PHP 5.6 is phpseclib 3's minimum version
+                    // so in theory we could support this BUT, "64-bit format codes are not available for
+                    // 32-bit versions" and phpseclib works on 32-bit installs. on 32-bit installs
+                    // 64-bit floats can be used to get larger numbers then 32-bit signed ints would allow
+                    // for. sure, you're not gonna get the full precision of 64-bit numbers but just because
+                    // you need > 32-bit precision doesn't mean you need the full 64-bit precision
+                    extract(unpack('Nupper/Nlower', self::shift($data, 8)));
+                    $temp = $upper ? 4294967296 * $upper : 0;
+                    $temp += $lower < 0 ? ($lower & 0x7FFFFFFFF) + 0x80000000 : $lower;
+                    // $temp = hexdec(bin2hex(self::shift($data, 8)));
+                    $result[] = $temp;
+                    continue 2;
+            }
+            list(, $length) = unpack('N', self::shift($data, 4));
+            if (strlen($data) < $length) {
+                throw new \LengthException("$length bytes needed; " . strlen($data) . ' bytes available');
+            }
+            $temp = self::shift($data, $length);
+            switch ($format[$i]) {
+                case 'i':
+                    $result[] = new BigInteger($temp, -256);
+                    break;
+                case 's':
+                    $result[] = $temp;
+                    break;
+                case 'L':
+                    $result[] = explode(',', $temp);
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     * Create SSH2-style string
+     *
+     * @param string $format
+     * @param string|int|float|array|bool ...$elements
+     * @return string
+     */
+    public static function packSSH2($format, ...$elements)
+    {
+        $format = self::formatPack($format);
+        if (strlen($format) != count($elements)) {
+            throw new \InvalidArgumentException('There must be as many arguments as there are characters in the $format string');
+        }
+        $result = '';
+        for ($i = 0; $i < strlen($format); $i++) {
+            $element = $elements[$i];
+            switch ($format[$i]) {
+                case 'C':
+                    if (!is_int($element)) {
+                        throw new \InvalidArgumentException('Bytes must be represented as an integer between 0 and 255, inclusive.');
+                    }
+                    $result .= pack('C', $element);
+                    break;
+                case 'b':
+                    if (!is_bool($element)) {
+                        throw new \InvalidArgumentException('A boolean parameter was expected.');
+                    }
+                    $result .= $element ? "\1" : "\0";
+                    break;
+                case 'Q':
+                    if (!is_int($element) && !is_float($element)) {
+                        throw new \InvalidArgumentException('An integer was expected.');
+                    }
+                    // 4294967296 == 1 << 32
+                    $result .= pack('NN', $element / 4294967296, $element);
+                    break;
+                case 'N':
+                    if (is_float($element)) {
+                        $element = (int) $element;
+                    }
+                    if (!is_int($element)) {
+                        throw new \InvalidArgumentException('An integer was expected.');
+                    }
+                    $result .= pack('N', $element);
+                    break;
+                case 's':
+                    if (!self::is_stringable($element)) {
+                        throw new \InvalidArgumentException('A string was expected.');
+                    }
+                    $result .= pack('Na*', strlen($element), $element);
+                    break;
+                case 'i':
+                    if (!$element instanceof BigInteger && !$element instanceof FiniteField\Integer) {
+                        throw new \InvalidArgumentException('A phpseclib3\Math\BigInteger or phpseclib3\Math\Common\FiniteField\Integer object was expected.');
+                    }
+                    $element = $element->toBytes(true);
+                    $result .= pack('Na*', strlen($element), $element);
+                    break;
+                case 'L':
+                    if (!is_array($element)) {
+                        throw new \InvalidArgumentException('An array was expected.');
+                    }
+                    $element = implode(',', $element);
+                    $result .= pack('Na*', strlen($element), $element);
+                    break;
+                default:
+                    throw new \InvalidArgumentException('$format contains an invalid character');
+            }
+        }
+        return $result;
+    }
+
+    /**
+     * Expand a pack string
+     *
+     * Converts C5 to CCCCC, for example.
+     *
+     * @param string $format
+     * @return string
+     */
+    private static function formatPack($format)
+    {
+        $parts = preg_split('#(\d+)#', $format, -1, PREG_SPLIT_DELIM_CAPTURE);
+        $format = '';
+        for ($i = 1; $i < count($parts); $i += 2) {
+            $format .= substr($parts[$i - 1], 0, -1) . str_repeat(substr($parts[$i - 1], -1), $parts[$i]);
+        }
+        $format .= $parts[$i - 1];
+
+        return $format;
+    }
+
+    /**
+     * Convert binary data into bits
+     *
+     * bin2hex / hex2bin refer to base-256 encoded data as binary, whilst
+     * decbin / bindec refer to base-2 encoded data as binary. For the purposes
+     * of this function, bin refers to base-256 encoded data whilst bits refers
+     * to base-2 encoded data
+     *
+     * @param string $x
+     * @return string
+     */
+    public static function bits2bin($x)
+    {
+        /*
+        // the pure-PHP approach is faster than the GMP approach
+        if (function_exists('gmp_export')) {
+             return strlen($x) ? gmp_export(gmp_init($x, 2)) : gmp_init(0);
+        }
+        */
+
+        if (preg_match('#[^01]#', $x)) {
+            throw new \RuntimeException('The only valid characters are 0 and 1');
+        }
+
+        if (!defined('PHP_INT_MIN')) {
+            define('PHP_INT_MIN', ~PHP_INT_MAX);
+        }
+
+        $length = strlen($x);
+        if (!$length) {
+            return '';
+        }
+        $block_size = PHP_INT_SIZE << 3;
+        $pad = $block_size - ($length % $block_size);
+        if ($pad != $block_size) {
+            $x = str_repeat('0', $pad) . $x;
+        }
+
+        $parts = str_split($x, $block_size);
+        $str = '';
+        foreach ($parts as $part) {
+            $xor = $part[0] == '1' ? PHP_INT_MIN : 0;
+            $part[0] = '0';
+            $str .= pack(
+                PHP_INT_SIZE == 4 ? 'N' : 'J',
+                $xor ^ eval('return 0b' . $part . ';')
+            );
+        }
+        return ltrim($str, "\0");
+    }
+
+    /**
+     * Convert bits to binary data
+     *
+     * @param string $x
+     * @return string
+     */
+    public static function bin2bits($x, $trim = true)
+    {
+        /*
+        // the pure-PHP approach is slower than the GMP approach BUT
+        // i want to the pure-PHP version to be easily unit tested as well
+        if (function_exists('gmp_import')) {
+            return gmp_strval(gmp_import($x), 2);
+        }
+        */
+
+        $len = strlen($x);
+        $mod = $len % PHP_INT_SIZE;
+        if ($mod) {
+            $x = str_pad($x, $len + PHP_INT_SIZE - $mod, "\0", STR_PAD_LEFT);
+        }
+
+        $bits = '';
+        if (PHP_INT_SIZE == 4) {
+            $digits = unpack('N*', $x);
+            foreach ($digits as $digit) {
+                $bits .= sprintf('%032b', $digit);
+            }
+        } else {
+            $digits = unpack('J*', $x);
+            foreach ($digits as $digit) {
+                $bits .= sprintf('%064b', $digit);
+            }
+        }
+
+        return $trim ? ltrim($bits, '0') : $bits;
+    }
+
+    /**
+     * Switch Endianness Bit Order
+     *
+     * @param string $x
+     * @return string
+     */
+    public static function switchEndianness($x)
+    {
+        $r = '';
+        for ($i = strlen($x) - 1; $i >= 0; $i--) {
+            $b = ord($x[$i]);
+            if (PHP_INT_SIZE === 8) {
+                // 3 operations
+                // from http://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith64BitsDiv
+                $r .= chr((($b * 0x0202020202) & 0x010884422010) % 1023);
+            } else {
+                // 7 operations
+                // from http://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith32Bits
+                $p1 = ($b * 0x0802) & 0x22110;
+                $p2 = ($b * 0x8020) & 0x88440;
+                $r .= chr(
+                    (($p1 | $p2) * 0x10101) >> 16
+                );
+            }
+        }
+        return $r;
+    }
+
+    /**
+     * Increment the current string
+     *
+     * @param string $var
+     * @return string
+     */
+    public static function increment_str(&$var)
+    {
+        if (function_exists('sodium_increment')) {
+            $var = strrev($var);
+            sodium_increment($var);
+            $var = strrev($var);
+            return $var;
+        }
+
+        for ($i = 4; $i <= strlen($var); $i += 4) {
+            $temp = substr($var, -$i, 4);
+            switch ($temp) {
+                case "\xFF\xFF\xFF\xFF":
+                    $var = substr_replace($var, "\x00\x00\x00\x00", -$i, 4);
+                    break;
+                case "\x7F\xFF\xFF\xFF":
+                    $var = substr_replace($var, "\x80\x00\x00\x00", -$i, 4);
+                    return $var;
+                default:
+                    $temp = unpack('Nnum', $temp);
+                    $var = substr_replace($var, pack('N', $temp['num'] + 1), -$i, 4);
+                    return $var;
+            }
+        }
+
+        $remainder = strlen($var) % 4;
+
+        if ($remainder == 0) {
+            return $var;
+        }
+
+        $temp = unpack('Nnum', str_pad(substr($var, 0, $remainder), 4, "\0", STR_PAD_LEFT));
+        $temp = substr(pack('N', $temp['num'] + 1), -$remainder);
+        $var = substr_replace($var, $temp, 0, $remainder);
+
+        return $var;
+    }
+
+    /**
+     * Find whether the type of a variable is string (or could be converted to one)
+     *
+     * @param mixed $var
+     * @return bool
+     * @psalm-assert-if-true string|\Stringable $var
+     */
+    public static function is_stringable($var)
+    {
+        return is_string($var) || (is_object($var) && method_exists($var, '__toString'));
+    }
+
+    /**
+     * Constant Time Base64-decoding
+     *
+     * ParagoneIE\ConstantTime doesn't use libsodium if it's available so we'll do so
+     * ourselves. see https://github.com/paragonie/constant_time_encoding/issues/39
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function base64_decode($data)
+    {
+        return function_exists('sodium_base642bin') ?
+            sodium_base642bin($data, SODIUM_BASE64_VARIANT_ORIGINAL_NO_PADDING, '=') :
+            Base64::decode($data);
+    }
+
+    /**
+     * Constant Time Base64-decoding (URL safe)
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function base64url_decode($data)
+    {
+        // return self::base64_decode(str_replace(['-', '_'], ['+', '/'], $data));
+
+        return function_exists('sodium_base642bin') ?
+            sodium_base642bin($data, SODIUM_BASE64_VARIANT_URLSAFE_NO_PADDING, '=') :
+            Base64UrlSafe::decode($data);
+    }
+
+    /**
+     * Constant Time Base64-encoding
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function base64_encode($data)
+    {
+        return function_exists('sodium_bin2base64') ?
+            sodium_bin2base64($data, SODIUM_BASE64_VARIANT_ORIGINAL) :
+            Base64::encode($data);
+    }
+
+    /**
+     * Constant Time Base64-encoding (URL safe)
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function base64url_encode($data)
+    {
+        // return str_replace(['+', '/'], ['-', '_'], self::base64_encode($data));
+
+        return function_exists('sodium_bin2base64') ?
+            sodium_bin2base64($data, SODIUM_BASE64_VARIANT_URLSAFE) :
+            Base64UrlSafe::encode($data);
+    }
+
+    /**
+     * Constant Time Hex Decoder
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function hex2bin($data)
+    {
+        return function_exists('sodium_hex2bin') ?
+            sodium_hex2bin($data) :
+            Hex::decode($data);
+    }
+
+    /**
+     * Constant Time Hex Encoder
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function bin2hex($data)
+    {
+        return function_exists('sodium_bin2hex') ?
+            sodium_bin2hex($data) :
+            Hex::encode($data);
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/AES.php

+<?php
+
+/**
+ * Pure-PHP implementation of AES.
+ *
+ * Uses mcrypt, if available/possible, and an internal implementation, otherwise.
+ *
+ * PHP version 5
+ *
+ * NOTE: Since AES.php is (for compatibility and phpseclib-historical reasons) virtually
+ * just a wrapper to Rijndael.php you may consider using Rijndael.php instead of
+ * to save one include_once().
+ *
+ * If {@link self::setKeyLength() setKeyLength()} isn't called, it'll be calculated from
+ * {@link self::setKey() setKey()}.  ie. if the key is 128-bits, the key length will be 128-bits.  If it's 136-bits
+ * it'll be null-padded to 192-bits and 192 bits will be the key length until {@link self::setKey() setKey()}
+ * is called, again, at which point, it'll be recalculated.
+ *
+ * Since \phpseclib3\Crypt\AES extends \phpseclib3\Crypt\Rijndael, some functions are available to be called that, in the context of AES, don't
+ * make a whole lot of sense.  {@link self::setBlockLength() setBlockLength()}, for instance.  Calling that function,
+ * however possible, won't do anything (AES has a fixed block length whereas Rijndael has a variable one).
+ *
+ * Here's a short example of how to use this library:
+ * <code>
+ * <?php
+ *    include 'vendor/autoload.php';
+ *
+ *    $aes = new \phpseclib3\Crypt\AES('ctr');
+ *
+ *    $aes->setKey('abcdefghijklmnop');
+ *
+ *    $size = 10 * 1024;
+ *    $plaintext = '';
+ *    for ($i = 0; $i < $size; $i++) {
+ *        $plaintext.= 'a';
+ *    }
+ *
+ *    echo $aes->decrypt($aes->encrypt($plaintext));
+ * ?>
+ * </code>
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2008 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt;
+
+/**
+ * Pure-PHP implementation of AES.
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+class AES extends Rijndael
+{
+    /**
+     * Dummy function
+     *
+     * Since \phpseclib3\Crypt\AES extends \phpseclib3\Crypt\Rijndael, this function is, technically, available, but it doesn't do anything.
+     *
+     * @see \phpseclib3\Crypt\Rijndael::setBlockLength()
+     * @param int $length
+     * @throws \BadMethodCallException anytime it's called
+     */
+    public function setBlockLength($length)
+    {
+        throw new \BadMethodCallException('The block length cannot be set for AES.');
+    }
+
+    /**
+     * Sets the key length
+     *
+     * Valid key lengths are 128, 192, and 256.  Set the link to bool(false) to disable a fixed key length
+     *
+     * @see \phpseclib3\Crypt\Rijndael:setKeyLength()
+     * @param int $length
+     * @throws \LengthException if the key length isn't supported
+     */
+    public function setKeyLength($length)
+    {
+        switch ($length) {
+            case 128:
+            case 192:
+            case 256:
+                break;
+            default:
+                throw new \LengthException('Key of size ' . $length . ' not supported by this algorithm. Only keys of sizes 128, 192 or 256 supported');
+        }
+        parent::setKeyLength($length);
+    }
+
+    /**
+     * Sets the key.
+     *
+     * Rijndael supports five different key lengths, AES only supports three.
+     *
+     * @see \phpseclib3\Crypt\Rijndael:setKey()
+     * @see setKeyLength()
+     * @param string $key
+     * @throws \LengthException if the key length isn't supported
+     */
+    public function setKey($key)
+    {
+        switch (strlen($key)) {
+            case 16:
+            case 24:
+            case 32:
+                break;
+            default:
+                throw new \LengthException('Key of size ' . strlen($key) . ' not supported by this algorithm. Only keys of sizes 16, 24 or 32 supported');
+        }
+
+        parent::setKey($key);
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Blowfish.php

+<?php
+
+/**
+ * Pure-PHP implementation of Blowfish.
+ *
+ * Uses mcrypt, if available, and an internal implementation, otherwise.
+ *
+ * PHP version 5
+ *
+ * Useful resources are as follows:
+ *
+ *  - {@link http://en.wikipedia.org/wiki/Blowfish_(cipher) Wikipedia description of Blowfish}
+ *
+ * # An overview of bcrypt vs Blowfish
+ *
+ * OpenSSH private keys use a customized version of bcrypt. Specifically, instead of
+ * encrypting OrpheanBeholderScryDoubt 64 times OpenSSH's bcrypt variant encrypts
+ * OxychromaticBlowfishSwatDynamite 64 times. so we can't use crypt().
+ *
+ * bcrypt is basically Blowfish but instead of performing the key expansion once it performs
+ * the expansion 129 times for each round, with the first key expansion interleaving the salt
+ * and password. This renders OpenSSL unusable and forces us to use a pure-PHP implementation
+ * of blowfish.
+ *
+ * # phpseclib's four different _encryptBlock() implementations
+ *
+ * When using Blowfish as an encryption algorithm, _encryptBlock() is called 9 + 512 +
+ * (the number of blocks in the plaintext) times.
+ *
+ * Each of the first 9 calls to _encryptBlock() modify the P-array. Each of the next 512
+ * calls modify the S-boxes. The remaining _encryptBlock() calls operate on the plaintext to
+ * produce the ciphertext. In the pure-PHP implementation of Blowfish these remaining
+ * _encryptBlock() calls are highly optimized through the use of eval(). Among other things,
+ * P-array lookups are eliminated by hard-coding the key-dependent P-array values, and thus we
+ * have explained 2 of the 4 different _encryptBlock() implementations.
+ *
+ * With bcrypt things are a bit different. _encryptBlock() is called 1,079,296 times,
+ * assuming 16 rounds (which is what OpenSSH's bcrypt defaults to). The eval()-optimized
+ * _encryptBlock() isn't as beneficial because the P-array values are not constant. Well, they
+ * are constant, but only for, at most, 777 _encryptBlock() calls, which is equivalent to ~6KB
+ * of data. The average length of back to back _encryptBlock() calls with a fixed P-array is
+ * 514.12, which is ~4KB of data. Creating an eval()-optimized _encryptBlock() has an upfront
+ * cost, which is CPU dependent and is probably not going to be worth it for just ~4KB of
+ * data. Conseqeuently, bcrypt does not benefit from the eval()-optimized _encryptBlock().
+ *
+ * The regular _encryptBlock() does unpack() and pack() on every call, as well, and that can
+ * begin to add up after one million function calls.
+ *
+ * In theory, one might think that it might be beneficial to rewrite all block ciphers so
+ * that, instead of passing strings to _encryptBlock(), you convert the string to an array of
+ * integers and then pass successive subarrays of that array to _encryptBlock. This, however,
+ * kills PHP's memory use. Like let's say you have a 1MB long string. After doing
+ * $in = str_repeat('a', 1024 * 1024); PHP's memory utilization jumps up by ~1MB. After doing
+ * $blocks = str_split($in, 4); it jumps up by an additional ~16MB. After
+ * $blocks = array_map(fn($x) => unpack('N*', $x), $blocks); it jumps up by an additional
+ * ~90MB, yielding a 106x increase in memory usage. Consequently, it bcrypt calls a different
+ * _encryptBlock() then the regular Blowfish does. That said, the Blowfish _encryptBlock() is
+ * basically just a thin wrapper around the bcrypt _encryptBlock(), so there's that.
+ *
+ * This explains 3 of the 4 _encryptBlock() implementations. the last _encryptBlock()
+ * implementation can best be understood by doing Ctrl + F and searching for where
+ * self::$use_reg_intval is defined.
+ *
+ * # phpseclib's three different _setupKey() implementations
+ *
+ * Every bcrypt round is the equivalent of encrypting 512KB of data. Since OpenSSH uses 16
+ * rounds by default that's ~8MB of data that's essentially being encrypted whenever
+ * you use bcrypt. That's a lot of data, however, bcrypt operates within tighter constraints
+ * than regular Blowfish, so we can use that to our advantage. In particular, whereas Blowfish
+ * supports variable length keys, in bcrypt, the initial "key" is the sha512 hash of the
+ * password. sha512 hashes are 512 bits or 64 bytes long and thus the bcrypt keys are of a
+ * fixed length whereas Blowfish keys are not of a fixed length.
+ *
+ * bcrypt actually has two different key expansion steps. The first one (expandstate) is
+ * constantly XOR'ing every _encryptBlock() parameter against the salt prior _encryptBlock()'s
+ * being called. The second one (expand0state) is more similar to Blowfish's _setupKey()
+ * but it can still use the fixed length key optimization discussed above and can do away with
+ * the pack() / unpack() calls.
+ *
+ * I suppose _setupKey() could be made to be a thin wrapper around expandstate() but idk it's
+ * just a lot of work for very marginal benefits as _setupKey() is only called once for
+ * regular Blowfish vs the 128 times it's called --per round-- with bcrypt.
+ *
+ * # blowfish + bcrypt in the same class
+ *
+ * Altho there's a lot of Blowfish code that bcrypt doesn't re-use, bcrypt does re-use the
+ * initial S-boxes, the initial P-array and the int-only _encryptBlock() implementation.
+ *
+ * # Credit
+ *
+ * phpseclib's bcrypt implementation is based losely off of OpenSSH's implementation:
+ *
+ * https://github.com/openssh/openssh-portable/blob/master/openbsd-compat/bcrypt_pbkdf.c
+ *
+ * Here's a short example of how to use this library:
+ * <code>
+ * <?php
+ *    include 'vendor/autoload.php';
+ *
+ *    $blowfish = new \phpseclib3\Crypt\Blowfish('ctr');
+ *
+ *    $blowfish->setKey('12345678901234567890123456789012');
+ *
+ *    $plaintext = str_repeat('a', 1024);
+ *
+ *    echo $blowfish->decrypt($blowfish->encrypt($plaintext));
+ * ?>
+ * </code>
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @author    Hans-Juergen Petrich <petrich@tronic-media.com>
+ * @copyright 2007 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt;
+
+use phpseclib3\Crypt\Common\BlockCipher;
+
+/**
+ * Pure-PHP implementation of Blowfish.
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ * @author  Hans-Juergen Petrich <petrich@tronic-media.com>
+ */
+class Blowfish extends BlockCipher
+{
+    /**
+     * Block Length of the cipher
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::block_size
+     * @var int
+     */
+    protected $block_size = 8;
+
+    /**
+     * The mcrypt specific name of the cipher
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::cipher_name_mcrypt
+     * @var string
+     */
+    protected $cipher_name_mcrypt = 'blowfish';
+
+    /**
+     * Optimizing value while CFB-encrypting
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::cfb_init_len
+     * @var int
+     */
+    protected $cfb_init_len = 500;
+
+    /**
+     * The fixed subkeys boxes ($sbox0 - $sbox3) with 256 entries each
+     *
+     * S-Box 0
+     *
+     * @var    array
+     */
+    private static $sbox0 = [
+        0xd1310ba6, 0x98dfb5ac, 0x2ffd72db, 0xd01adfb7, 0xb8e1afed, 0x6a267e96, 0xba7c9045, 0xf12c7f99,
+        0x24a19947, 0xb3916cf7, 0x0801f2e2, 0x858efc16, 0x636920d8, 0x71574e69, 0xa458fea3, 0xf4933d7e,
+        0x0d95748f, 0x728eb658, 0x718bcd58, 0x82154aee, 0x7b54a41d, 0xc25a59b5, 0x9c30d539, 0x2af26013,
+        0xc5d1b023, 0x286085f0, 0xca417918, 0xb8db38ef, 0x8e79dcb0, 0x603a180e, 0x6c9e0e8b, 0xb01e8a3e,
+        0xd71577c1, 0xbd314b27, 0x78af2fda, 0x55605c60, 0xe65525f3, 0xaa55ab94, 0x57489862, 0x63e81440,
+        0x55ca396a, 0x2aab10b6, 0xb4cc5c34, 0x1141e8ce, 0xa15486af, 0x7c72e993, 0xb3ee1411, 0x636fbc2a,
+        0x2ba9c55d, 0x741831f6, 0xce5c3e16, 0x9b87931e, 0xafd6ba33, 0x6c24cf5c, 0x7a325381, 0x28958677,
+        0x3b8f4898, 0x6b4bb9af, 0xc4bfe81b, 0x66282193, 0x61d809cc, 0xfb21a991, 0x487cac60, 0x5dec8032,
+        0xef845d5d, 0xe98575b1, 0xdc262302, 0xeb651b88, 0x23893e81, 0xd396acc5, 0x0f6d6ff3, 0x83f44239,
+        0x2e0b4482, 0xa4842004, 0x69c8f04a, 0x9e1f9b5e, 0x21c66842, 0xf6e96c9a, 0x670c9c61, 0xabd388f0,
+        0x6a51a0d2, 0xd8542f68, 0x960fa728, 0xab5133a3, 0x6eef0b6c, 0x137a3be4, 0xba3bf050, 0x7efb2a98,
+        0xa1f1651d, 0x39af0176, 0x66ca593e, 0x82430e88, 0x8cee8619, 0x456f9fb4, 0x7d84a5c3, 0x3b8b5ebe,
+        0xe06f75d8, 0x85c12073, 0x401a449f, 0x56c16aa6, 0x4ed3aa62, 0x363f7706, 0x1bfedf72, 0x429b023d,
+        0x37d0d724, 0xd00a1248, 0xdb0fead3, 0x49f1c09b, 0x075372c9, 0x80991b7b, 0x25d479d8, 0xf6e8def7,
+        0xe3fe501a, 0xb6794c3b, 0x976ce0bd, 0x04c006ba, 0xc1a94fb6, 0x409f60c4, 0x5e5c9ec2, 0x196a2463,
+        0x68fb6faf, 0x3e6c53b5, 0x1339b2eb, 0x3b52ec6f, 0x6dfc511f, 0x9b30952c, 0xcc814544, 0xaf5ebd09,
+        0xbee3d004, 0xde334afd, 0x660f2807, 0x192e4bb3, 0xc0cba857, 0x45c8740f, 0xd20b5f39, 0xb9d3fbdb,
+        0x5579c0bd, 0x1a60320a, 0xd6a100c6, 0x402c7279, 0x679f25fe, 0xfb1fa3cc, 0x8ea5e9f8, 0xdb3222f8,
+        0x3c7516df, 0xfd616b15, 0x2f501ec8, 0xad0552ab, 0x323db5fa, 0xfd238760, 0x53317b48, 0x3e00df82,
+        0x9e5c57bb, 0xca6f8ca0, 0x1a87562e, 0xdf1769db, 0xd542a8f6, 0x287effc3, 0xac6732c6, 0x8c4f5573,
+        0x695b27b0, 0xbbca58c8, 0xe1ffa35d, 0xb8f011a0, 0x10fa3d98, 0xfd2183b8, 0x4afcb56c, 0x2dd1d35b,
+        0x9a53e479, 0xb6f84565, 0xd28e49bc, 0x4bfb9790, 0xe1ddf2da, 0xa4cb7e33, 0x62fb1341, 0xcee4c6e8,
+        0xef20cada, 0x36774c01, 0xd07e9efe, 0x2bf11fb4, 0x95dbda4d, 0xae909198, 0xeaad8e71, 0x6b93d5a0,
+        0xd08ed1d0, 0xafc725e0, 0x8e3c5b2f, 0x8e7594b7, 0x8ff6e2fb, 0xf2122b64, 0x8888b812, 0x900df01c,
+        0x4fad5ea0, 0x688fc31c, 0xd1cff191, 0xb3a8c1ad, 0x2f2f2218, 0xbe0e1777, 0xea752dfe, 0x8b021fa1,
+        0xe5a0cc0f, 0xb56f74e8, 0x18acf3d6, 0xce89e299, 0xb4a84fe0, 0xfd13e0b7, 0x7cc43b81, 0xd2ada8d9,
+        0x165fa266, 0x80957705, 0x93cc7314, 0x211a1477, 0xe6ad2065, 0x77b5fa86, 0xc75442f5, 0xfb9d35cf,
+        0xebcdaf0c, 0x7b3e89a0, 0xd6411bd3, 0xae1e7e49, 0x00250e2d, 0x2071b35e, 0x226800bb, 0x57b8e0af,
+        0x2464369b, 0xf009b91e, 0x5563911d, 0x59dfa6aa, 0x78c14389, 0xd95a537f, 0x207d5ba2, 0x02e5b9c5,
+        0x83260376, 0x6295cfa9, 0x11c81968, 0x4e734a41, 0xb3472dca, 0x7b14a94a, 0x1b510052, 0x9a532915,
+        0xd60f573f, 0xbc9bc6e4, 0x2b60a476, 0x81e67400, 0x08ba6fb5, 0x571be91f, 0xf296ec6b, 0x2a0dd915,
+        0xb6636521, 0xe7b9f9b6, 0xff34052e, 0xc5855664, 0x53b02d5d, 0xa99f8fa1, 0x08ba4799, 0x6e85076a
+    ];
+
+    /**
+     * S-Box 1
+     *
+     * @var    array
+     */
+    private static $sbox1 = [
+        0x4b7a70e9, 0xb5b32944, 0xdb75092e, 0xc4192623, 0xad6ea6b0, 0x49a7df7d, 0x9cee60b8, 0x8fedb266,
+        0xecaa8c71, 0x699a17ff, 0x5664526c, 0xc2b19ee1, 0x193602a5, 0x75094c29, 0xa0591340, 0xe4183a3e,
+        0x3f54989a, 0x5b429d65, 0x6b8fe4d6, 0x99f73fd6, 0xa1d29c07, 0xefe830f5, 0x4d2d38e6, 0xf0255dc1,
+        0x4cdd2086, 0x8470eb26, 0x6382e9c6, 0x021ecc5e, 0x09686b3f, 0x3ebaefc9, 0x3c971814, 0x6b6a70a1,
+        0x687f3584, 0x52a0e286, 0xb79c5305, 0xaa500737, 0x3e07841c, 0x7fdeae5c, 0x8e7d44ec, 0x5716f2b8,
+        0xb03ada37, 0xf0500c0d, 0xf01c1f04, 0x0200b3ff, 0xae0cf51a, 0x3cb574b2, 0x25837a58, 0xdc0921bd,
+        0xd19113f9, 0x7ca92ff6, 0x94324773, 0x22f54701, 0x3ae5e581, 0x37c2dadc, 0xc8b57634, 0x9af3dda7,
+        0xa9446146, 0x0fd0030e, 0xecc8c73e, 0xa4751e41, 0xe238cd99, 0x3bea0e2f, 0x3280bba1, 0x183eb331,
+        0x4e548b38, 0x4f6db908, 0x6f420d03, 0xf60a04bf, 0x2cb81290, 0x24977c79, 0x5679b072, 0xbcaf89af,
+        0xde9a771f, 0xd9930810, 0xb38bae12, 0xdccf3f2e, 0x5512721f, 0x2e6b7124, 0x501adde6, 0x9f84cd87,
+        0x7a584718, 0x7408da17, 0xbc9f9abc, 0xe94b7d8c, 0xec7aec3a, 0xdb851dfa, 0x63094366, 0xc464c3d2,
+        0xef1c1847, 0x3215d908, 0xdd433b37, 0x24c2ba16, 0x12a14d43, 0x2a65c451, 0x50940002, 0x133ae4dd,
+        0x71dff89e, 0x10314e55, 0x81ac77d6, 0x5f11199b, 0x043556f1, 0xd7a3c76b, 0x3c11183b, 0x5924a509,
+        0xf28fe6ed, 0x97f1fbfa, 0x9ebabf2c, 0x1e153c6e, 0x86e34570, 0xeae96fb1, 0x860e5e0a, 0x5a3e2ab3,
+        0x771fe71c, 0x4e3d06fa, 0x2965dcb9, 0x99e71d0f, 0x803e89d6, 0x5266c825, 0x2e4cc978, 0x9c10b36a,
+        0xc6150eba, 0x94e2ea78, 0xa5fc3c53, 0x1e0a2df4, 0xf2f74ea7, 0x361d2b3d, 0x1939260f, 0x19c27960,
+        0x5223a708, 0xf71312b6, 0xebadfe6e, 0xeac31f66, 0xe3bc4595, 0xa67bc883, 0xb17f37d1, 0x018cff28,
+        0xc332ddef, 0xbe6c5aa5, 0x65582185, 0x68ab9802, 0xeecea50f, 0xdb2f953b, 0x2aef7dad, 0x5b6e2f84,
+        0x1521b628, 0x29076170, 0xecdd4775, 0x619f1510, 0x13cca830, 0xeb61bd96, 0x0334fe1e, 0xaa0363cf,
+        0xb5735c90, 0x4c70a239, 0xd59e9e0b, 0xcbaade14, 0xeecc86bc, 0x60622ca7, 0x9cab5cab, 0xb2f3846e,
+        0x648b1eaf, 0x19bdf0ca, 0xa02369b9, 0x655abb50, 0x40685a32, 0x3c2ab4b3, 0x319ee9d5, 0xc021b8f7,
+        0x9b540b19, 0x875fa099, 0x95f7997e, 0x623d7da8, 0xf837889a, 0x97e32d77, 0x11ed935f, 0x16681281,
+        0x0e358829, 0xc7e61fd6, 0x96dedfa1, 0x7858ba99, 0x57f584a5, 0x1b227263, 0x9b83c3ff, 0x1ac24696,
+        0xcdb30aeb, 0x532e3054, 0x8fd948e4, 0x6dbc3128, 0x58ebf2ef, 0x34c6ffea, 0xfe28ed61, 0xee7c3c73,
+        0x5d4a14d9, 0xe864b7e3, 0x42105d14, 0x203e13e0, 0x45eee2b6, 0xa3aaabea, 0xdb6c4f15, 0xfacb4fd0,
+        0xc742f442, 0xef6abbb5, 0x654f3b1d, 0x41cd2105, 0xd81e799e, 0x86854dc7, 0xe44b476a, 0x3d816250,
+        0xcf62a1f2, 0x5b8d2646, 0xfc8883a0, 0xc1c7b6a3, 0x7f1524c3, 0x69cb7492, 0x47848a0b, 0x5692b285,
+        0x095bbf00, 0xad19489d, 0x1462b174, 0x23820e00, 0x58428d2a, 0x0c55f5ea, 0x1dadf43e, 0x233f7061,
+        0x3372f092, 0x8d937e41, 0xd65fecf1, 0x6c223bdb, 0x7cde3759, 0xcbee7460, 0x4085f2a7, 0xce77326e,
+        0xa6078084, 0x19f8509e, 0xe8efd855, 0x61d99735, 0xa969a7aa, 0xc50c06c2, 0x5a04abfc, 0x800bcadc,
+        0x9e447a2e, 0xc3453484, 0xfdd56705, 0x0e1e9ec9, 0xdb73dbd3, 0x105588cd, 0x675fda79, 0xe3674340,
+        0xc5c43465, 0x713e38d8, 0x3d28f89e, 0xf16dff20, 0x153e21e7, 0x8fb03d4a, 0xe6e39f2b, 0xdb83adf7
+    ];
+
+    /**
+     * S-Box 2
+     *
+     * @var    array
+     */
+    private static $sbox2 = [
+        0xe93d5a68, 0x948140f7, 0xf64c261c, 0x94692934, 0x411520f7, 0x7602d4f7, 0xbcf46b2e, 0xd4a20068,
+        0xd4082471, 0x3320f46a, 0x43b7d4b7, 0x500061af, 0x1e39f62e, 0x97244546, 0x14214f74, 0xbf8b8840,
+        0x4d95fc1d, 0x96b591af, 0x70f4ddd3, 0x66a02f45, 0xbfbc09ec, 0x03bd9785, 0x7fac6dd0, 0x31cb8504,
+        0x96eb27b3, 0x55fd3941, 0xda2547e6, 0xabca0a9a, 0x28507825, 0x530429f4, 0x0a2c86da, 0xe9b66dfb,
+        0x68dc1462, 0xd7486900, 0x680ec0a4, 0x27a18dee, 0x4f3ffea2, 0xe887ad8c, 0xb58ce006, 0x7af4d6b6,
+        0xaace1e7c, 0xd3375fec, 0xce78a399, 0x406b2a42, 0x20fe9e35, 0xd9f385b9, 0xee39d7ab, 0x3b124e8b,
+        0x1dc9faf7, 0x4b6d1856, 0x26a36631, 0xeae397b2, 0x3a6efa74, 0xdd5b4332, 0x6841e7f7, 0xca7820fb,
+        0xfb0af54e, 0xd8feb397, 0x454056ac, 0xba489527, 0x55533a3a, 0x20838d87, 0xfe6ba9b7, 0xd096954b,
+        0x55a867bc, 0xa1159a58, 0xcca92963, 0x99e1db33, 0xa62a4a56, 0x3f3125f9, 0x5ef47e1c, 0x9029317c,
+        0xfdf8e802, 0x04272f70, 0x80bb155c, 0x05282ce3, 0x95c11548, 0xe4c66d22, 0x48c1133f, 0xc70f86dc,
+        0x07f9c9ee, 0x41041f0f, 0x404779a4, 0x5d886e17, 0x325f51eb, 0xd59bc0d1, 0xf2bcc18f, 0x41113564,
+        0x257b7834, 0x602a9c60, 0xdff8e8a3, 0x1f636c1b, 0x0e12b4c2, 0x02e1329e, 0xaf664fd1, 0xcad18115,
+        0x6b2395e0, 0x333e92e1, 0x3b240b62, 0xeebeb922, 0x85b2a20e, 0xe6ba0d99, 0xde720c8c, 0x2da2f728,
+        0xd0127845, 0x95b794fd, 0x647d0862, 0xe7ccf5f0, 0x5449a36f, 0x877d48fa, 0xc39dfd27, 0xf33e8d1e,
+        0x0a476341, 0x992eff74, 0x3a6f6eab, 0xf4f8fd37, 0xa812dc60, 0xa1ebddf8, 0x991be14c, 0xdb6e6b0d,
+        0xc67b5510, 0x6d672c37, 0x2765d43b, 0xdcd0e804, 0xf1290dc7, 0xcc00ffa3, 0xb5390f92, 0x690fed0b,
+        0x667b9ffb, 0xcedb7d9c, 0xa091cf0b, 0xd9155ea3, 0xbb132f88, 0x515bad24, 0x7b9479bf, 0x763bd6eb,
+        0x37392eb3, 0xcc115979, 0x8026e297, 0xf42e312d, 0x6842ada7, 0xc66a2b3b, 0x12754ccc, 0x782ef11c,
+        0x6a124237, 0xb79251e7, 0x06a1bbe6, 0x4bfb6350, 0x1a6b1018, 0x11caedfa, 0x3d25bdd8, 0xe2e1c3c9,
+        0x44421659, 0x0a121386, 0xd90cec6e, 0xd5abea2a, 0x64af674e, 0xda86a85f, 0xbebfe988, 0x64e4c3fe,
+        0x9dbc8057, 0xf0f7c086, 0x60787bf8, 0x6003604d, 0xd1fd8346, 0xf6381fb0, 0x7745ae04, 0xd736fccc,
+        0x83426b33, 0xf01eab71, 0xb0804187, 0x3c005e5f, 0x77a057be, 0xbde8ae24, 0x55464299, 0xbf582e61,
+        0x4e58f48f, 0xf2ddfda2, 0xf474ef38, 0x8789bdc2, 0x5366f9c3, 0xc8b38e74, 0xb475f255, 0x46fcd9b9,
+        0x7aeb2661, 0x8b1ddf84, 0x846a0e79, 0x915f95e2, 0x466e598e, 0x20b45770, 0x8cd55591, 0xc902de4c,
+        0xb90bace1, 0xbb8205d0, 0x11a86248, 0x7574a99e, 0xb77f19b6, 0xe0a9dc09, 0x662d09a1, 0xc4324633,
+        0xe85a1f02, 0x09f0be8c, 0x4a99a025, 0x1d6efe10, 0x1ab93d1d, 0x0ba5a4df, 0xa186f20f, 0x2868f169,
+        0xdcb7da83, 0x573906fe, 0xa1e2ce9b, 0x4fcd7f52, 0x50115e01, 0xa70683fa, 0xa002b5c4, 0x0de6d027,
+        0x9af88c27, 0x773f8641, 0xc3604c06, 0x61a806b5, 0xf0177a28, 0xc0f586e0, 0x006058aa, 0x30dc7d62,
+        0x11e69ed7, 0x2338ea63, 0x53c2dd94, 0xc2c21634, 0xbbcbee56, 0x90bcb6de, 0xebfc7da1, 0xce591d76,
+        0x6f05e409, 0x4b7c0188, 0x39720a3d, 0x7c927c24, 0x86e3725f, 0x724d9db9, 0x1ac15bb4, 0xd39eb8fc,
+        0xed545578, 0x08fca5b5, 0xd83d7cd3, 0x4dad0fc4, 0x1e50ef5e, 0xb161e6f8, 0xa28514d9, 0x6c51133c,
+        0x6fd5c7e7, 0x56e14ec4, 0x362abfce, 0xddc6c837, 0xd79a3234, 0x92638212, 0x670efa8e, 0x406000e0
+    ];
+
+    /**
+     * S-Box 3
+     *
+     * @var    array
+     */
+    private static $sbox3 = [
+        0x3a39ce37, 0xd3faf5cf, 0xabc27737, 0x5ac52d1b, 0x5cb0679e, 0x4fa33742, 0xd3822740, 0x99bc9bbe,
+        0xd5118e9d, 0xbf0f7315, 0xd62d1c7e, 0xc700c47b, 0xb78c1b6b, 0x21a19045, 0xb26eb1be, 0x6a366eb4,
+        0x5748ab2f, 0xbc946e79, 0xc6a376d2, 0x6549c2c8, 0x530ff8ee, 0x468dde7d, 0xd5730a1d, 0x4cd04dc6,
+        0x2939bbdb, 0xa9ba4650, 0xac9526e8, 0xbe5ee304, 0xa1fad5f0, 0x6a2d519a, 0x63ef8ce2, 0x9a86ee22,
+        0xc089c2b8, 0x43242ef6, 0xa51e03aa, 0x9cf2d0a4, 0x83c061ba, 0x9be96a4d, 0x8fe51550, 0xba645bd6,
+        0x2826a2f9, 0xa73a3ae1, 0x4ba99586, 0xef5562e9, 0xc72fefd3, 0xf752f7da, 0x3f046f69, 0x77fa0a59,
+        0x80e4a915, 0x87b08601, 0x9b09e6ad, 0x3b3ee593, 0xe990fd5a, 0x9e34d797, 0x2cf0b7d9, 0x022b8b51,
+        0x96d5ac3a, 0x017da67d, 0xd1cf3ed6, 0x7c7d2d28, 0x1f9f25cf, 0xadf2b89b, 0x5ad6b472, 0x5a88f54c,
+        0xe029ac71, 0xe019a5e6, 0x47b0acfd, 0xed93fa9b, 0xe8d3c48d, 0x283b57cc, 0xf8d56629, 0x79132e28,
+        0x785f0191, 0xed756055, 0xf7960e44, 0xe3d35e8c, 0x15056dd4, 0x88f46dba, 0x03a16125, 0x0564f0bd,
+        0xc3eb9e15, 0x3c9057a2, 0x97271aec, 0xa93a072a, 0x1b3f6d9b, 0x1e6321f5, 0xf59c66fb, 0x26dcf319,
+        0x7533d928, 0xb155fdf5, 0x03563482, 0x8aba3cbb, 0x28517711, 0xc20ad9f8, 0xabcc5167, 0xccad925f,
+        0x4de81751, 0x3830dc8e, 0x379d5862, 0x9320f991, 0xea7a90c2, 0xfb3e7bce, 0x5121ce64, 0x774fbe32,
+        0xa8b6e37e, 0xc3293d46, 0x48de5369, 0x6413e680, 0xa2ae0810, 0xdd6db224, 0x69852dfd, 0x09072166,
+        0xb39a460a, 0x6445c0dd, 0x586cdecf, 0x1c20c8ae, 0x5bbef7dd, 0x1b588d40, 0xccd2017f, 0x6bb4e3bb,
+        0xdda26a7e, 0x3a59ff45, 0x3e350a44, 0xbcb4cdd5, 0x72eacea8, 0xfa6484bb, 0x8d6612ae, 0xbf3c6f47,
+        0xd29be463, 0x542f5d9e, 0xaec2771b, 0xf64e6370, 0x740e0d8d, 0xe75b1357, 0xf8721671, 0xaf537d5d,
+        0x4040cb08, 0x4eb4e2cc, 0x34d2466a, 0x0115af84, 0xe1b00428, 0x95983a1d, 0x06b89fb4, 0xce6ea048,
+        0x6f3f3b82, 0x3520ab82, 0x011a1d4b, 0x277227f8, 0x611560b1, 0xe7933fdc, 0xbb3a792b, 0x344525bd,
+        0xa08839e1, 0x51ce794b, 0x2f32c9b7, 0xa01fbac9, 0xe01cc87e, 0xbcc7d1f6, 0xcf0111c3, 0xa1e8aac7,
+        0x1a908749, 0xd44fbd9a, 0xd0dadecb, 0xd50ada38, 0x0339c32a, 0xc6913667, 0x8df9317c, 0xe0b12b4f,
+        0xf79e59b7, 0x43f5bb3a, 0xf2d519ff, 0x27d9459c, 0xbf97222c, 0x15e6fc2a, 0x0f91fc71, 0x9b941525,
+        0xfae59361, 0xceb69ceb, 0xc2a86459, 0x12baa8d1, 0xb6c1075e, 0xe3056a0c, 0x10d25065, 0xcb03a442,
+        0xe0ec6e0e, 0x1698db3b, 0x4c98a0be, 0x3278e964, 0x9f1f9532, 0xe0d392df, 0xd3a0342b, 0x8971f21e,
+        0x1b0a7441, 0x4ba3348c, 0xc5be7120, 0xc37632d8, 0xdf359f8d, 0x9b992f2e, 0xe60b6f47, 0x0fe3f11d,
+        0xe54cda54, 0x1edad891, 0xce6279cf, 0xcd3e7e6f, 0x1618b166, 0xfd2c1d05, 0x848fd2c5, 0xf6fb2299,
+        0xf523f357, 0xa6327623, 0x93a83531, 0x56cccd02, 0xacf08162, 0x5a75ebb5, 0x6e163697, 0x88d273cc,
+        0xde966292, 0x81b949d0, 0x4c50901b, 0x71c65614, 0xe6c6c7bd, 0x327a140a, 0x45e1d006, 0xc3f27b9a,
+        0xc9aa53fd, 0x62a80f00, 0xbb25bfe2, 0x35bdd2f6, 0x71126905, 0xb2040222, 0xb6cbcf7c, 0xcd769c2b,
+        0x53113ec0, 0x1640e3d3, 0x38abbd60, 0x2547adf0, 0xba38209c, 0xf746ce76, 0x77afa1c5, 0x20756060,
+        0x85cbfe4e, 0x8ae88dd8, 0x7aaaf9b0, 0x4cf9aa7e, 0x1948c25c, 0x02fb8a8c, 0x01c36ae4, 0xd6ebe1f9,
+        0x90d4f869, 0xa65cdea0, 0x3f09252d, 0xc208e69f, 0xb74e6132, 0xce77e25b, 0x578fdfe3, 0x3ac372e6
+    ];
+
+    /**
+     * P-Array consists of 18 32-bit subkeys
+     *
+     * @var array
+     */
+    private static $parray = [
+        0x243f6a88, 0x85a308d3, 0x13198a2e, 0x03707344, 0xa4093822, 0x299f31d0,
+        0x082efa98, 0xec4e6c89, 0x452821e6, 0x38d01377, 0xbe5466cf, 0x34e90c6c,
+        0xc0ac29b7, 0xc97c50dd, 0x3f84d5b5, 0xb5470917, 0x9216d5d9, 0x8979fb1b
+    ];
+
+    /**
+     * The BCTX-working Array
+     *
+     * Holds the expanded key [p] and the key-depended s-boxes [sb]
+     *
+     * @var array
+     */
+    private $bctx;
+
+    /**
+     * Holds the last used key
+     *
+     * @var array
+     */
+    private $kl;
+
+    /**
+     * The Key Length (in bytes)
+     * {@internal The max value is 256 / 8 = 32, the min value is 128 / 8 = 16.  Exists in conjunction with $Nk
+     *    because the encryption / decryption / key schedule creation requires this number and not $key_length.  We could
+     *    derive this from $key_length or vice versa, but that'd mean we'd have to do multiple shift operations, so in lieu
+     *    of that, we'll just precompute it once.}
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::setKeyLength()
+     * @var int
+     */
+    protected $key_length = 16;
+
+    /**
+     * Default Constructor.
+     *
+     * @param string $mode
+     * @throws \InvalidArgumentException if an invalid / unsupported mode is provided
+     */
+    public function __construct($mode)
+    {
+        parent::__construct($mode);
+
+        if ($this->mode == self::MODE_STREAM) {
+            throw new \InvalidArgumentException('Block ciphers cannot be ran in stream mode');
+        }
+    }
+
+    /**
+     * Sets the key length.
+     *
+     * Key lengths can be between 32 and 448 bits.
+     *
+     * @param int $length
+     */
+    public function setKeyLength($length)
+    {
+        if ($length < 32 || $length > 448) {
+                throw new \LengthException('Key size of ' . $length . ' bits is not supported by this algorithm. Only keys of sizes between 32 and 448 bits are supported');
+        }
+
+        $this->key_length = $length >> 3;
+
+        parent::setKeyLength($length);
+    }
+
+    /**
+     * Test for engine validity
+     *
+     * This is mainly just a wrapper to set things up for \phpseclib3\Crypt\Common\SymmetricKey::isValidEngine()
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::isValidEngine()
+     * @param int $engine
+     * @return bool
+     */
+    protected function isValidEngineHelper($engine)
+    {
+        if ($engine == self::ENGINE_OPENSSL) {
+            if ($this->key_length < 16) {
+                return false;
+            }
+            // quoting https://www.openssl.org/news/openssl-3.0-notes.html, OpenSSL 3.0.1
+            // "Moved all variations of the EVP ciphers CAST5, BF, IDEA, SEED, RC2, RC4, RC5, and DES to the legacy provider"
+            // in theory openssl_get_cipher_methods() should catch this but, on GitHub Actions, at least, it does not
+            if (version_compare(preg_replace('#OpenSSL (\d+\.\d+\.\d+) .*#', '$1', OPENSSL_VERSION_TEXT), '3.0.1', '>=')) {
+                return false;
+            }
+            $this->cipher_name_openssl_ecb = 'bf-ecb';
+            $this->cipher_name_openssl = 'bf-' . $this->openssl_translate_mode();
+        }
+
+        return parent::isValidEngineHelper($engine);
+    }
+
+    /**
+     * Setup the key (expansion)
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::_setupKey()
+     */
+    protected function setupKey()
+    {
+        if (isset($this->kl['key']) && $this->key === $this->kl['key']) {
+            // already expanded
+            return;
+        }
+        $this->kl = ['key' => $this->key];
+
+        /* key-expanding p[] and S-Box building sb[] */
+        $this->bctx = [
+            'p'  => [],
+            'sb' => [
+                self::$sbox0,
+                self::$sbox1,
+                self::$sbox2,
+                self::$sbox3
+            ]
+        ];
+
+        // unpack binary string in unsigned chars
+        $key  = array_values(unpack('C*', $this->key));
+        $keyl = count($key);
+        // with bcrypt $keyl will always be 16 (because the key is the sha512 of the key you provide)
+        for ($j = 0, $i = 0; $i < 18; ++$i) {
+            // xor P1 with the first 32-bits of the key, xor P2 with the second 32-bits ...
+            for ($data = 0, $k = 0; $k < 4; ++$k) {
+                $data = ($data << 8) | $key[$j];
+                if (++$j >= $keyl) {
+                    $j = 0;
+                }
+            }
+            $this->bctx['p'][] = self::$parray[$i] ^ intval($data);
+        }
+
+        // encrypt the zero-string, replace P1 and P2 with the encrypted data,
+        // encrypt P3 and P4 with the new P1 and P2, do it with all P-array and subkeys
+        $data = "\0\0\0\0\0\0\0\0";
+        for ($i = 0; $i < 18; $i += 2) {
+            list($l, $r) = array_values(unpack('N*', $data = $this->encryptBlock($data)));
+            $this->bctx['p'][$i    ] = $l;
+            $this->bctx['p'][$i + 1] = $r;
+        }
+        for ($i = 0; $i < 4; ++$i) {
+            for ($j = 0; $j < 256; $j += 2) {
+                list($l, $r) = array_values(unpack('N*', $data = $this->encryptBlock($data)));
+                $this->bctx['sb'][$i][$j    ] = $l;
+                $this->bctx['sb'][$i][$j + 1] = $r;
+            }
+        }
+    }
+
+    /**
+     * Initialize Static Variables
+     */
+    protected static function initialize_static_variables()
+    {
+        if (is_float(self::$sbox2[0])) {
+            self::$sbox0 = array_map('intval', self::$sbox0);
+            self::$sbox1 = array_map('intval', self::$sbox1);
+            self::$sbox2 = array_map('intval', self::$sbox2);
+            self::$sbox3 = array_map('intval', self::$sbox3);
+            self::$parray = array_map('intval', self::$parray);
+        }
+
+        parent::initialize_static_variables();
+    }
+
+    /**
+     * bcrypt
+     *
+     * @param string $sha2pass
+     * @param string $sha2salt
+     * @access private
+     * @return string
+     */
+    private static function bcrypt_hash($sha2pass, $sha2salt)
+    {
+        $p = self::$parray;
+        $sbox0 = self::$sbox0;
+        $sbox1 = self::$sbox1;
+        $sbox2 = self::$sbox2;
+        $sbox3 = self::$sbox3;
+
+        $cdata = array_values(unpack('N*', 'OxychromaticBlowfishSwatDynamite'));
+        $sha2pass = array_values(unpack('N*', $sha2pass));
+        $sha2salt = array_values(unpack('N*', $sha2salt));
+
+        self::expandstate($sha2salt, $sha2pass, $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 0; $i < 64; $i++) {
+            self::expand0state($sha2salt, $sbox0, $sbox1, $sbox2, $sbox3, $p);
+            self::expand0state($sha2pass, $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        for ($i = 0; $i < 64; $i++) {
+            for ($j = 0; $j < 8; $j += 2) { // count($cdata) == 8
+                list($cdata[$j], $cdata[$j + 1]) = self::encryptBlockHelperFast($cdata[$j], $cdata[$j + 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+            }
+        }
+
+        return pack('L*', ...$cdata);
+    }
+
+    /**
+     * Performs OpenSSH-style bcrypt
+     *
+     * @param string $pass
+     * @param string $salt
+     * @param int $keylen
+     * @param int $rounds
+     * @access public
+     * @return string
+     */
+    public static function bcrypt_pbkdf($pass, $salt, $keylen, $rounds)
+    {
+        self::initialize_static_variables();
+
+        if (PHP_INT_SIZE == 4) {
+            throw new \RuntimeException('bcrypt is far too slow to be practical on 32-bit versions of PHP');
+        }
+
+        $sha2pass = hash('sha512', $pass, true);
+        $results = [];
+        $count = 1;
+        while (32 * count($results) < $keylen) {
+            $countsalt = $salt . pack('N', $count++);
+            $sha2salt = hash('sha512', $countsalt, true);
+            $out = $tmpout = self::bcrypt_hash($sha2pass, $sha2salt);
+            for ($i = 1; $i < $rounds; $i++) {
+                $sha2salt = hash('sha512', $tmpout, true);
+                $tmpout = self::bcrypt_hash($sha2pass, $sha2salt);
+                $out ^= $tmpout;
+            }
+            $results[] = $out;
+        }
+        $output = '';
+        for ($i = 0; $i < 32; $i++) {
+            foreach ($results as $result) {
+                $output .= $result[$i];
+            }
+        }
+        return substr($output, 0, $keylen);
+    }
+
+    /**
+     * Key expansion without salt
+     *
+     * @access private
+     * @param int[] $key
+     * @param int[] $sbox0
+     * @param int[] $sbox1
+     * @param int[] $sbox2
+     * @param int[] $sbox3
+     * @param int[] $p
+     * @see self::_bcrypt_hash()
+     */
+    private static function expand0state(array $key, array &$sbox0, array &$sbox1, array &$sbox2, array &$sbox3, array &$p)
+    {
+        // expand0state is basically the same thing as this:
+        //return self::expandstate(array_fill(0, 16, 0), $key);
+        // but this separate function eliminates a bunch of XORs and array lookups
+
+        $p = [
+            $p[0] ^ $key[0],
+            $p[1] ^ $key[1],
+            $p[2] ^ $key[2],
+            $p[3] ^ $key[3],
+            $p[4] ^ $key[4],
+            $p[5] ^ $key[5],
+            $p[6] ^ $key[6],
+            $p[7] ^ $key[7],
+            $p[8] ^ $key[8],
+            $p[9] ^ $key[9],
+            $p[10] ^ $key[10],
+            $p[11] ^ $key[11],
+            $p[12] ^ $key[12],
+            $p[13] ^ $key[13],
+            $p[14] ^ $key[14],
+            $p[15] ^ $key[15],
+            $p[16] ^ $key[0],
+            $p[17] ^ $key[1]
+        ];
+
+        // @codingStandardsIgnoreStart
+        list( $p[0],  $p[1]) = self::encryptBlockHelperFast(     0,      0, $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[2],  $p[3]) = self::encryptBlockHelperFast($p[ 0], $p[ 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[4],  $p[5]) = self::encryptBlockHelperFast($p[ 2], $p[ 3], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[6],  $p[7]) = self::encryptBlockHelperFast($p[ 4], $p[ 5], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[8],  $p[9]) = self::encryptBlockHelperFast($p[ 6], $p[ 7], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[10], $p[11]) = self::encryptBlockHelperFast($p[ 8], $p[ 9], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[12], $p[13]) = self::encryptBlockHelperFast($p[10], $p[11], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[14], $p[15]) = self::encryptBlockHelperFast($p[12], $p[13], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[16], $p[17]) = self::encryptBlockHelperFast($p[14], $p[15], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        // @codingStandardsIgnoreEnd
+
+        list($sbox0[0], $sbox0[1]) = self::encryptBlockHelperFast($p[16], $p[17], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2; $i < 256; $i += 2) {
+            list($sbox0[$i], $sbox0[$i + 1]) = self::encryptBlockHelperFast($sbox0[$i - 2], $sbox0[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        list($sbox1[0], $sbox1[1]) = self::encryptBlockHelperFast($sbox0[254], $sbox0[255], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2; $i < 256; $i += 2) {
+            list($sbox1[$i], $sbox1[$i + 1]) = self::encryptBlockHelperFast($sbox1[$i - 2], $sbox1[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        list($sbox2[0], $sbox2[1]) = self::encryptBlockHelperFast($sbox1[254], $sbox1[255], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2; $i < 256; $i += 2) {
+            list($sbox2[$i], $sbox2[$i + 1]) = self::encryptBlockHelperFast($sbox2[$i - 2], $sbox2[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        list($sbox3[0], $sbox3[1]) = self::encryptBlockHelperFast($sbox2[254], $sbox2[255], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2; $i < 256; $i += 2) {
+            list($sbox3[$i], $sbox3[$i + 1]) = self::encryptBlockHelperFast($sbox3[$i - 2], $sbox3[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+    }
+
+    /**
+     * Key expansion with salt
+     *
+     * @access private
+     * @param int[] $data
+     * @param int[] $key
+     * @param int[] $sbox0
+     * @param int[] $sbox1
+     * @param int[] $sbox2
+     * @param int[] $sbox3
+     * @param int[] $p
+     * @see self::_bcrypt_hash()
+     */
+    private static function expandstate(array $data, array $key, array &$sbox0, array &$sbox1, array &$sbox2, array &$sbox3, array &$p)
+    {
+        $p = [
+            $p[0] ^ $key[0],
+            $p[1] ^ $key[1],
+            $p[2] ^ $key[2],
+            $p[3] ^ $key[3],
+            $p[4] ^ $key[4],
+            $p[5] ^ $key[5],
+            $p[6] ^ $key[6],
+            $p[7] ^ $key[7],
+            $p[8] ^ $key[8],
+            $p[9] ^ $key[9],
+            $p[10] ^ $key[10],
+            $p[11] ^ $key[11],
+            $p[12] ^ $key[12],
+            $p[13] ^ $key[13],
+            $p[14] ^ $key[14],
+            $p[15] ^ $key[15],
+            $p[16] ^ $key[0],
+            $p[17] ^ $key[1]
+        ];
+
+        // @codingStandardsIgnoreStart
+        list( $p[0],  $p[1]) = self::encryptBlockHelperFast($data[ 0]         , $data[ 1]         , $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[2],  $p[3]) = self::encryptBlockHelperFast($data[ 2] ^ $p[ 0], $data[ 3] ^ $p[ 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[4],  $p[5]) = self::encryptBlockHelperFast($data[ 4] ^ $p[ 2], $data[ 5] ^ $p[ 3], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[6],  $p[7]) = self::encryptBlockHelperFast($data[ 6] ^ $p[ 4], $data[ 7] ^ $p[ 5], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list( $p[8],  $p[9]) = self::encryptBlockHelperFast($data[ 8] ^ $p[ 6], $data[ 9] ^ $p[ 7], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[10], $p[11]) = self::encryptBlockHelperFast($data[10] ^ $p[ 8], $data[11] ^ $p[ 9], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[12], $p[13]) = self::encryptBlockHelperFast($data[12] ^ $p[10], $data[13] ^ $p[11], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[14], $p[15]) = self::encryptBlockHelperFast($data[14] ^ $p[12], $data[15] ^ $p[13], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        list($p[16], $p[17]) = self::encryptBlockHelperFast($data[ 0] ^ $p[14], $data[ 1] ^ $p[15], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        // @codingStandardsIgnoreEnd
+
+        list($sbox0[0], $sbox0[1]) = self::encryptBlockHelperFast($data[2] ^ $p[16], $data[3] ^ $p[17], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2, $j = 4; $i < 256; $i += 2, $j = ($j + 2) % 16) { // instead of 16 maybe count($data) would be better?
+            list($sbox0[$i], $sbox0[$i + 1]) = self::encryptBlockHelperFast($data[$j] ^ $sbox0[$i - 2], $data[$j + 1] ^ $sbox0[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        list($sbox1[0], $sbox1[1]) = self::encryptBlockHelperFast($data[2] ^ $sbox0[254], $data[3] ^ $sbox0[255], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2, $j = 4; $i < 256; $i += 2, $j = ($j + 2) % 16) {
+            list($sbox1[$i], $sbox1[$i + 1]) = self::encryptBlockHelperFast($data[$j] ^ $sbox1[$i - 2], $data[$j + 1] ^ $sbox1[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        list($sbox2[0], $sbox2[1]) = self::encryptBlockHelperFast($data[2] ^ $sbox1[254], $data[3] ^ $sbox1[255], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2, $j = 4; $i < 256; $i += 2, $j = ($j + 2) % 16) {
+            list($sbox2[$i], $sbox2[$i + 1]) = self::encryptBlockHelperFast($data[$j] ^ $sbox2[$i - 2], $data[$j + 1] ^ $sbox2[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+
+        list($sbox3[0], $sbox3[1]) = self::encryptBlockHelperFast($data[2] ^ $sbox2[254], $data[3] ^ $sbox2[255], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        for ($i = 2, $j = 4; $i < 256; $i += 2, $j = ($j + 2) % 16) {
+            list($sbox3[$i], $sbox3[$i + 1]) = self::encryptBlockHelperFast($data[$j] ^ $sbox3[$i - 2], $data[$j + 1] ^ $sbox3[$i - 1], $sbox0, $sbox1, $sbox2, $sbox3, $p);
+        }
+    }
+
+    /**
+     * Encrypts a block
+     *
+     * @param string $in
+     * @return string
+     */
+    protected function encryptBlock($in)
+    {
+        $p = $this->bctx['p'];
+        // extract($this->bctx['sb'], EXTR_PREFIX_ALL, 'sb'); // slower
+        $sb_0 = $this->bctx['sb'][0];
+        $sb_1 = $this->bctx['sb'][1];
+        $sb_2 = $this->bctx['sb'][2];
+        $sb_3 = $this->bctx['sb'][3];
+
+        $in = unpack('N*', $in);
+        $l = $in[1];
+        $r = $in[2];
+
+        list($r, $l) = PHP_INT_SIZE == 4 ?
+            self::encryptBlockHelperSlow($l, $r, $sb_0, $sb_1, $sb_2, $sb_3, $p) :
+            self::encryptBlockHelperFast($l, $r, $sb_0, $sb_1, $sb_2, $sb_3, $p);
+
+        return pack("N*", $r, $l);
+    }
+
+    /**
+     * Fast helper function for block encryption
+     *
+     * @access private
+     * @param int $x0
+     * @param int $x1
+     * @param int[] $sbox0
+     * @param int[] $sbox1
+     * @param int[] $sbox2
+     * @param int[] $sbox3
+     * @param int[] $p
+     * @return int[]
+     */
+    private static function encryptBlockHelperFast($x0, $x1, array $sbox0, array $sbox1, array $sbox2, array $sbox3, array $p)
+    {
+        $x0 ^= $p[0];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[1];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[2];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[3];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[4];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[5];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[6];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[7];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[8];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[9];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[10];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[11];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[12];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[13];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[14];
+        $x1 ^= ((($sbox0[($x0 & 0xFF000000) >> 24] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[15];
+        $x0 ^= ((($sbox0[($x1 & 0xFF000000) >> 24] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[16];
+
+        return [$x1 & 0xFFFFFFFF ^ $p[17], $x0 & 0xFFFFFFFF];
+    }
+
+    /**
+     * Slow helper function for block encryption
+     *
+     * @access private
+     * @param int $x0
+     * @param int $x1
+     * @param int[] $sbox0
+     * @param int[] $sbox1
+     * @param int[] $sbox2
+     * @param int[] $sbox3
+     * @param int[] $p
+     * @return int[]
+     */
+    private static function encryptBlockHelperSlow($x0, $x1, array $sbox0, array $sbox1, array $sbox2, array $sbox3, array $p)
+    {
+        // -16777216 == intval(0xFF000000) on 32-bit PHP installs
+        $x0 ^= $p[0];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[1];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[2];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[3];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[4];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[5];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[6];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[7];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[8];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[9];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[10];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[11];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[12];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[13];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[14];
+        $x1 ^= self::safe_intval((self::safe_intval($sbox0[(($x0 & -16777216) >> 24) & 0xFF] + $sbox1[($x0 & 0xFF0000) >> 16]) ^ $sbox2[($x0 & 0xFF00) >> 8]) + $sbox3[$x0 & 0xFF]) ^ $p[15];
+        $x0 ^= self::safe_intval((self::safe_intval($sbox0[(($x1 & -16777216) >> 24) & 0xFF] + $sbox1[($x1 & 0xFF0000) >> 16]) ^ $sbox2[($x1 & 0xFF00) >> 8]) + $sbox3[$x1 & 0xFF]) ^ $p[16];
+
+        return [$x1 ^ $p[17], $x0];
+    }
+
+    /**
+     * Decrypts a block
+     *
+     * @param string $in
+     * @return string
+     */
+    protected function decryptBlock($in)
+    {
+        $p = $this->bctx['p'];
+        $sb_0 = $this->bctx['sb'][0];
+        $sb_1 = $this->bctx['sb'][1];
+        $sb_2 = $this->bctx['sb'][2];
+        $sb_3 = $this->bctx['sb'][3];
+
+        $in = unpack('N*', $in);
+        $l = $in[1];
+        $r = $in[2];
+
+        for ($i = 17; $i > 2; $i -= 2) {
+            $l ^= $p[$i];
+            $r ^= self::safe_intval((self::safe_intval($sb_0[$l >> 24 & 0xff] + $sb_1[$l >> 16 & 0xff]) ^
+                  $sb_2[$l >>  8 & 0xff]) +
+                  $sb_3[$l       & 0xff]);
+
+            $r ^= $p[$i - 1];
+            $l ^= self::safe_intval((self::safe_intval($sb_0[$r >> 24 & 0xff] + $sb_1[$r >> 16 & 0xff]) ^
+                  $sb_2[$r >>  8 & 0xff]) +
+                  $sb_3[$r       & 0xff]);
+        }
+        return pack('N*', $r ^ $p[0], $l ^ $p[1]);
+    }
+
+    /**
+     * Setup the performance-optimized function for de/encrypt()
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::_setupInlineCrypt()
+     */
+    protected function setupInlineCrypt()
+    {
+        $p = $this->bctx['p'];
+        $init_crypt = '
+            static $sb_0, $sb_1, $sb_2, $sb_3;
+            if (!$sb_0) {
+                $sb_0 = $this->bctx["sb"][0];
+                $sb_1 = $this->bctx["sb"][1];
+                $sb_2 = $this->bctx["sb"][2];
+                $sb_3 = $this->bctx["sb"][3];
+            }
+        ';
+
+        $safeint = self::safe_intval_inline();
+
+        // Generating encrypt code:
+        $encrypt_block = '
+            $in = unpack("N*", $in);
+            $l = $in[1];
+            $r = $in[2];
+        ';
+        for ($i = 0; $i < 16; $i += 2) {
+            $encrypt_block .= '
+                $l^= ' . $p[$i] . ';
+                $r^= ' . sprintf($safeint, '(' . sprintf($safeint, '$sb_0[$l >> 24 & 0xff] + $sb_1[$l >> 16 & 0xff]') . ' ^
+                      $sb_2[$l >>  8 & 0xff]) +
+                      $sb_3[$l       & 0xff]') . ';
+
+                $r^= ' . $p[$i + 1] . ';
+                $l^= ' . sprintf($safeint, '(' . sprintf($safeint, '$sb_0[$r >> 24 & 0xff] + $sb_1[$r >> 16 & 0xff]') . '  ^
+                      $sb_2[$r >>  8 & 0xff]) +
+                      $sb_3[$r       & 0xff]') . ';
+            ';
+        }
+        $encrypt_block .= '
+            $in = pack("N*",
+                $r ^ ' . $p[17] . ',
+                $l ^ ' . $p[16] . '
+            );
+        ';
+         // Generating decrypt code:
+        $decrypt_block = '
+            $in = unpack("N*", $in);
+            $l = $in[1];
+            $r = $in[2];
+        ';
+
+        for ($i = 17; $i > 2; $i -= 2) {
+            $decrypt_block .= '
+                $l^= ' . $p[$i] . ';
+                $r^= ' . sprintf($safeint, '(' . sprintf($safeint, '$sb_0[$l >> 24 & 0xff] + $sb_1[$l >> 16 & 0xff]') . ' ^
+                      $sb_2[$l >>  8 & 0xff]) +
+                      $sb_3[$l       & 0xff]') . ';
+
+                $r^= ' . $p[$i - 1] . ';
+                $l^= ' . sprintf($safeint, '(' . sprintf($safeint, '$sb_0[$r >> 24 & 0xff] + $sb_1[$r >> 16 & 0xff]') . ' ^
+                      $sb_2[$r >>  8 & 0xff]) +
+                      $sb_3[$r       & 0xff]') . ';
+            ';
+        }
+
+        $decrypt_block .= '
+            $in = pack("N*",
+                $r ^ ' . $p[0] . ',
+                $l ^ ' . $p[1] . '
+            );
+        ';
+
+        $this->inline_crypt = $this->createInlineCryptFunction(
+            [
+               'init_crypt'    => $init_crypt,
+               'init_encrypt'  => '',
+               'init_decrypt'  => '',
+               'encrypt_block' => $encrypt_block,
+               'decrypt_block' => $decrypt_block
+            ]
+        );
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/ChaCha20.php

+<?php
+
+/**
+ * Pure-PHP implementation of ChaCha20.
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2019 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt;
+
+use phpseclib3\Exception\BadDecryptionException;
+use phpseclib3\Exception\InsufficientSetupException;
+
+/**
+ * Pure-PHP implementation of ChaCha20.
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+class ChaCha20 extends Salsa20
+{
+    /**
+     * The OpenSSL specific name of the cipher
+     *
+     * @var string
+     */
+    protected $cipher_name_openssl = 'chacha20';
+
+    /**
+     * Test for engine validity
+     *
+     * This is mainly just a wrapper to set things up for \phpseclib3\Crypt\Common\SymmetricKey::isValidEngine()
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     * @param int $engine
+     * @return bool
+     */
+    protected function isValidEngineHelper($engine)
+    {
+        switch ($engine) {
+            case self::ENGINE_LIBSODIUM:
+                // PHP 7.2.0 (30 Nov 2017) added support for libsodium
+
+                // we could probably make it so that if $this->counter == 0 then the first block would be done with either OpenSSL
+                // or PHP and then subsequent blocks would then be done with libsodium but idk - it's not a high priority atm
+
+                // we could also make it so that if $this->counter == 0 and $this->continuousBuffer then do the first string
+                // with libsodium and subsequent strings with openssl or pure-PHP but again not a high priority
+                return function_exists('sodium_crypto_aead_chacha20poly1305_ietf_encrypt') &&
+                       $this->key_length == 32 &&
+                       (($this->usePoly1305 && !isset($this->poly1305Key) && $this->counter == 0) || $this->counter == 1) &&
+                       !$this->continuousBuffer;
+            case self::ENGINE_OPENSSL:
+                // OpenSSL 1.1.0 (released 25 Aug 2016) added support for chacha20.
+                // PHP didn't support OpenSSL 1.1.0 until 7.0.19 (11 May 2017)
+
+                // if you attempt to provide openssl with a 128 bit key (as opposed to a 256 bit key) openssl will null
+                // pad the key to 256 bits and still use the expansion constant for 256-bit keys. the fact that
+                // openssl treats the IV as both the counter and nonce, however, let's us use openssl in continuous mode
+                // whereas libsodium does not
+                if ($this->key_length != 32) {
+                    return false;
+                }
+        }
+
+        return parent::isValidEngineHelper($engine);
+    }
+
+    /**
+     * Encrypts a message.
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     * @see self::crypt()
+     * @param string $plaintext
+     * @return string $ciphertext
+     */
+    public function encrypt($plaintext)
+    {
+        $this->setup();
+
+        if ($this->engine == self::ENGINE_LIBSODIUM) {
+            return $this->encrypt_with_libsodium($plaintext);
+        }
+
+        return parent::encrypt($plaintext);
+    }
+
+    /**
+     * Decrypts a message.
+     *
+     * $this->decrypt($this->encrypt($plaintext)) == $this->encrypt($this->encrypt($plaintext)).
+     * At least if the continuous buffer is disabled.
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see self::crypt()
+     * @param string $ciphertext
+     * @return string $plaintext
+     */
+    public function decrypt($ciphertext)
+    {
+        $this->setup();
+
+        if ($this->engine == self::ENGINE_LIBSODIUM) {
+            return $this->decrypt_with_libsodium($ciphertext);
+        }
+
+        return parent::decrypt($ciphertext);
+    }
+
+    /**
+     * Encrypts a message with libsodium
+     *
+     * @see self::encrypt()
+     * @param string $plaintext
+     * @return string $text
+     */
+    private function encrypt_with_libsodium($plaintext)
+    {
+        $params = [$plaintext, $this->aad, $this->nonce, $this->key];
+        $ciphertext = strlen($this->nonce) == 8 ?
+            sodium_crypto_aead_chacha20poly1305_encrypt(...$params) :
+            sodium_crypto_aead_chacha20poly1305_ietf_encrypt(...$params);
+        if (!$this->usePoly1305) {
+            return substr($ciphertext, 0, strlen($plaintext));
+        }
+
+        $newciphertext = substr($ciphertext, 0, strlen($plaintext));
+
+        $this->newtag = $this->usingGeneratedPoly1305Key && strlen($this->nonce) == 12 ?
+            substr($ciphertext, strlen($plaintext)) :
+            $this->poly1305($newciphertext);
+
+        return $newciphertext;
+    }
+
+    /**
+     * Decrypts a message with libsodium
+     *
+     * @see self::decrypt()
+     * @param string $ciphertext
+     * @return string $text
+     */
+    private function decrypt_with_libsodium($ciphertext)
+    {
+        $params = [$ciphertext, $this->aad, $this->nonce, $this->key];
+
+        if (isset($this->poly1305Key)) {
+            if ($this->oldtag === false) {
+                throw new InsufficientSetupException('Authentication Tag has not been set');
+            }
+            if ($this->usingGeneratedPoly1305Key && strlen($this->nonce) == 12) {
+                $plaintext = sodium_crypto_aead_chacha20poly1305_ietf_decrypt(...$params);
+                $this->oldtag = false;
+                if ($plaintext === false) {
+                    throw new BadDecryptionException('Derived authentication tag and supplied authentication tag do not match');
+                }
+                return $plaintext;
+            }
+            $newtag = $this->poly1305($ciphertext);
+            if ($this->oldtag != substr($newtag, 0, strlen($this->oldtag))) {
+                $this->oldtag = false;
+                throw new BadDecryptionException('Derived authentication tag and supplied authentication tag do not match');
+            }
+            $this->oldtag = false;
+        }
+
+        $plaintext = strlen($this->nonce) == 8 ?
+            sodium_crypto_aead_chacha20poly1305_encrypt(...$params) :
+            sodium_crypto_aead_chacha20poly1305_ietf_encrypt(...$params);
+
+        return substr($plaintext, 0, strlen($ciphertext));
+    }
+
+    /**
+     * Sets the nonce.
+     *
+     * @param string $nonce
+     */
+    public function setNonce($nonce)
+    {
+        if (!is_string($nonce)) {
+            throw new \UnexpectedValueException('The nonce should be a string');
+        }
+
+        /*
+          from https://tools.ietf.org/html/rfc7539#page-7
+
+          "Note also that the original ChaCha had a 64-bit nonce and 64-bit
+           block count.  We have modified this here to be more consistent with
+           recommendations in Section 3.2 of [RFC5116]."
+         */
+        switch (strlen($nonce)) {
+            case 8:  // 64 bits
+            case 12: // 96 bits
+                break;
+            default:
+                throw new \LengthException('Nonce of size ' . strlen($nonce) . ' not supported by this algorithm. Only 64-bit nonces or 96-bit nonces are supported');
+        }
+
+        $this->nonce = $nonce;
+        $this->changed = true;
+        $this->setEngine();
+    }
+
+    /**
+     * Setup the self::ENGINE_INTERNAL $engine
+     *
+     * (re)init, if necessary, the internal cipher $engine
+     *
+     * _setup() will be called each time if $changed === true
+     * typically this happens when using one or more of following public methods:
+     *
+     * - setKey()
+     *
+     * - setNonce()
+     *
+     * - First run of encrypt() / decrypt() with no init-settings
+     *
+     * @see self::setKey()
+     * @see self::setNonce()
+     * @see self::disableContinuousBuffer()
+     */
+    protected function setup()
+    {
+        if (!$this->changed) {
+            return;
+        }
+
+        $this->enbuffer = $this->debuffer = ['ciphertext' => '', 'counter' => $this->counter];
+
+        $this->changed = $this->nonIVChanged = false;
+
+        if ($this->nonce === false) {
+            throw new InsufficientSetupException('No nonce has been defined');
+        }
+
+        if ($this->key === false) {
+            throw new InsufficientSetupException('No key has been defined');
+        }
+
+        if ($this->usePoly1305 && !isset($this->poly1305Key)) {
+            $this->usingGeneratedPoly1305Key = true;
+            if ($this->engine == self::ENGINE_LIBSODIUM) {
+                return;
+            }
+            $this->createPoly1305Key();
+        }
+
+        $key = $this->key;
+        if (strlen($key) == 16) {
+            $constant = 'expand 16-byte k';
+            $key .= $key;
+        } else {
+            $constant = 'expand 32-byte k';
+        }
+
+        $this->p1 = $constant . $key;
+        $this->p2 = $this->nonce;
+        if (strlen($this->nonce) == 8) {
+            $this->p2 = "\0\0\0\0" . $this->p2;
+        }
+    }
+
+    /**
+     * The quarterround function
+     *
+     * @param int $a
+     * @param int $b
+     * @param int $c
+     * @param int $d
+     */
+    protected static function quarterRound(&$a, &$b, &$c, &$d)
+    {
+        // in https://datatracker.ietf.org/doc/html/rfc7539#section-2.1 the addition,
+        // xor'ing and rotation are all on the same line so i'm keeping it on the same
+        // line here as well
+        // @codingStandardsIgnoreStart
+        $a+= $b; $d = self::leftRotate(intval($d) ^ intval($a), 16);
+        $c+= $d; $b = self::leftRotate(intval($b) ^ intval($c), 12);
+        $a+= $b; $d = self::leftRotate(intval($d) ^ intval($a), 8);
+        $c+= $d; $b = self::leftRotate(intval($b) ^ intval($c), 7);
+        // @codingStandardsIgnoreEnd
+    }
+
+    /**
+     * The doubleround function
+     *
+     * @param int $x0 (by reference)
+     * @param int $x1 (by reference)
+     * @param int $x2 (by reference)
+     * @param int $x3 (by reference)
+     * @param int $x4 (by reference)
+     * @param int $x5 (by reference)
+     * @param int $x6 (by reference)
+     * @param int $x7 (by reference)
+     * @param int $x8 (by reference)
+     * @param int $x9 (by reference)
+     * @param int $x10 (by reference)
+     * @param int $x11 (by reference)
+     * @param int $x12 (by reference)
+     * @param int $x13 (by reference)
+     * @param int $x14 (by reference)
+     * @param int $x15 (by reference)
+     */
+    protected static function doubleRound(&$x0, &$x1, &$x2, &$x3, &$x4, &$x5, &$x6, &$x7, &$x8, &$x9, &$x10, &$x11, &$x12, &$x13, &$x14, &$x15)
+    {
+        // columnRound
+        static::quarterRound($x0, $x4, $x8, $x12);
+        static::quarterRound($x1, $x5, $x9, $x13);
+        static::quarterRound($x2, $x6, $x10, $x14);
+        static::quarterRound($x3, $x7, $x11, $x15);
+        // rowRound
+        static::quarterRound($x0, $x5, $x10, $x15);
+        static::quarterRound($x1, $x6, $x11, $x12);
+        static::quarterRound($x2, $x7, $x8, $x13);
+        static::quarterRound($x3, $x4, $x9, $x14);
+    }
+
+    /**
+     * The Salsa20 hash function function
+     *
+     * On my laptop this loop unrolled / function dereferenced version of parent::salsa20 encrypts 1mb of text in
+     * 0.65s vs the 0.85s that it takes with the parent method.
+     *
+     * If we were free to assume that the host OS would always be 64-bits then the if condition in leftRotate could
+     * be eliminated and we could knock this done to 0.60s.
+     *
+     * For comparison purposes, RC4 takes 0.16s and AES in CTR mode with the Eval engine takes 0.48s.
+     * AES in CTR mode with the PHP engine takes 1.19s. Salsa20 / ChaCha20 do not benefit as much from the Eval
+     * approach due to the fact that there are a lot less variables to de-reference, fewer loops to unroll, etc
+     *
+     * @param string $x
+     */
+    protected static function salsa20($x)
+    {
+        list(, $x0, $x1, $x2, $x3, $x4, $x5, $x6, $x7, $x8, $x9, $x10, $x11, $x12, $x13, $x14, $x15) = unpack('V*', $x);
+        $z0 = $x0;
+        $z1 = $x1;
+        $z2 = $x2;
+        $z3 = $x3;
+        $z4 = $x4;
+        $z5 = $x5;
+        $z6 = $x6;
+        $z7 = $x7;
+        $z8 = $x8;
+        $z9 = $x9;
+        $z10 = $x10;
+        $z11 = $x11;
+        $z12 = $x12;
+        $z13 = $x13;
+        $z14 = $x14;
+        $z15 = $x15;
+
+        // @codingStandardsIgnoreStart
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+
+        // columnRound
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 16);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 12);
+        $x0+= $x4; $x12 = self::leftRotate(intval($x12) ^ intval($x0), 8);
+        $x8+= $x12; $x4 = self::leftRotate(intval($x4) ^ intval($x8), 7);
+
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 16);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 12);
+        $x1+= $x5; $x13 = self::leftRotate(intval($x13) ^ intval($x1), 8);
+        $x9+= $x13; $x5 = self::leftRotate(intval($x5) ^ intval($x9), 7);
+
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 16);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 12);
+        $x2+= $x6; $x14 = self::leftRotate(intval($x14) ^ intval($x2), 8);
+        $x10+= $x14; $x6 = self::leftRotate(intval($x6) ^ intval($x10), 7);
+
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 16);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 12);
+        $x3+= $x7; $x15 = self::leftRotate(intval($x15) ^ intval($x3), 8);
+        $x11+= $x15; $x7 = self::leftRotate(intval($x7) ^ intval($x11), 7);
+
+        // rowRound
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 16);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 12);
+        $x0+= $x5; $x15 = self::leftRotate(intval($x15) ^ intval($x0), 8);
+        $x10+= $x15; $x5 = self::leftRotate(intval($x5) ^ intval($x10), 7);
+
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 16);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 12);
+        $x1+= $x6; $x12 = self::leftRotate(intval($x12) ^ intval($x1), 8);
+        $x11+= $x12; $x6 = self::leftRotate(intval($x6) ^ intval($x11), 7);
+
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 16);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 12);
+        $x2+= $x7; $x13 = self::leftRotate(intval($x13) ^ intval($x2), 8);
+        $x8+= $x13; $x7 = self::leftRotate(intval($x7) ^ intval($x8), 7);
+
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 16);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 12);
+        $x3+= $x4; $x14 = self::leftRotate(intval($x14) ^ intval($x3), 8);
+        $x9+= $x14; $x4 = self::leftRotate(intval($x4) ^ intval($x9), 7);
+        // @codingStandardsIgnoreEnd
+
+        $x0 += $z0;
+        $x1 += $z1;
+        $x2 += $z2;
+        $x3 += $z3;
+        $x4 += $z4;
+        $x5 += $z5;
+        $x6 += $z6;
+        $x7 += $z7;
+        $x8 += $z8;
+        $x9 += $z9;
+        $x10 += $z10;
+        $x11 += $z11;
+        $x12 += $z12;
+        $x13 += $z13;
+        $x14 += $z14;
+        $x15 += $z15;
+
+        return pack('V*', $x0, $x1, $x2, $x3, $x4, $x5, $x6, $x7, $x8, $x9, $x10, $x11, $x12, $x13, $x14, $x15);
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/AsymmetricKey.php

+<?php
+
+/**
+ * Base Class for all asymmetric key ciphers
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2016 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common;
+
+use phpseclib3\Crypt\DSA;
+use phpseclib3\Crypt\Hash;
+use phpseclib3\Crypt\RSA;
+use phpseclib3\Exception\NoKeyLoadedException;
+use phpseclib3\Exception\UnsupportedFormatException;
+use phpseclib3\Math\BigInteger;
+
+/**
+ * Base Class for all asymmetric cipher classes
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class AsymmetricKey
+{
+    /**
+     * Precomputed Zero
+     *
+     * @var \phpseclib3\Math\BigInteger
+     */
+    protected static $zero;
+
+    /**
+     * Precomputed One
+     *
+     * @var \phpseclib3\Math\BigInteger
+     */
+    protected static $one;
+
+    /**
+     * Format of the loaded key
+     *
+     * @var string
+     */
+    protected $format;
+
+    /**
+     * Hash function
+     *
+     * @var \phpseclib3\Crypt\Hash
+     */
+    protected $hash;
+
+    /**
+     * HMAC function
+     *
+     * @var \phpseclib3\Crypt\Hash
+     */
+    private $hmac;
+
+    /**
+     * Supported plugins (lower case)
+     *
+     * @see self::initialize_static_variables()
+     * @var array
+     */
+    private static $plugins = [];
+
+    /**
+     * Invisible plugins
+     *
+     * @see self::initialize_static_variables()
+     * @var array
+     */
+    private static $invisiblePlugins = [];
+
+    /**
+     * Available Engines
+     *
+     * @var boolean[]
+     */
+    protected static $engines = [];
+
+    /**
+     * Key Comment
+     *
+     * @var null|string
+     */
+    private $comment;
+
+    /**
+     * @param string $type
+     * @return string
+     */
+    abstract public function toString($type, array $options = []);
+
+    /**
+     * The constructor
+     */
+    protected function __construct()
+    {
+        self::initialize_static_variables();
+
+        $this->hash = new Hash('sha256');
+        $this->hmac = new Hash('sha256');
+    }
+
+    /**
+     * Initialize static variables
+     */
+    protected static function initialize_static_variables()
+    {
+        if (!isset(self::$zero)) {
+            self::$zero = new BigInteger(0);
+            self::$one = new BigInteger(1);
+        }
+
+        self::loadPlugins('Keys');
+        if (static::ALGORITHM != 'RSA' && static::ALGORITHM != 'DH') {
+            self::loadPlugins('Signature');
+        }
+    }
+
+    /**
+     * Load the key
+     *
+     * @param string $key
+     * @param string $password optional
+     * @return AsymmetricKey
+     */
+    public static function load($key, $password = false)
+    {
+        self::initialize_static_variables();
+
+        $components = false;
+        foreach (self::$plugins[static::ALGORITHM]['Keys'] as $format) {
+            if (isset(self::$invisiblePlugins[static::ALGORITHM]) && in_array($format, self::$invisiblePlugins[static::ALGORITHM])) {
+                continue;
+            }
+            try {
+                $components = $format::load($key, $password);
+            } catch (\Exception $e) {
+                $components = false;
+            }
+            if ($components !== false) {
+                break;
+            }
+        }
+
+        if ($components === false) {
+            throw new NoKeyLoadedException('Unable to read key');
+        }
+
+        $components['format'] = $format;
+        $components['secret'] = isset($components['secret']) ? $components['secret'] : '';
+        $comment = isset($components['comment']) ? $components['comment'] : null;
+        $new = static::onLoad($components);
+        $new->format = $format;
+        $new->comment = $comment;
+        return $new instanceof PrivateKey ?
+            $new->withPassword($password) :
+            $new;
+    }
+
+    /**
+     * Loads a private key
+     *
+     * @return PrivateKey
+     * @param string|array $key
+     * @param string $password optional
+     */
+    public static function loadPrivateKey($key, $password = '')
+    {
+        $key = self::load($key, $password);
+        if (!$key instanceof PrivateKey) {
+            throw new NoKeyLoadedException('The key that was loaded was not a private key');
+        }
+        return $key;
+    }
+
+    /**
+     * Loads a public key
+     *
+     * @return PublicKey
+     * @param string|array $key
+     */
+    public static function loadPublicKey($key)
+    {
+        $key = self::load($key);
+        if (!$key instanceof PublicKey) {
+            throw new NoKeyLoadedException('The key that was loaded was not a public key');
+        }
+        return $key;
+    }
+
+    /**
+     * Loads parameters
+     *
+     * @return AsymmetricKey
+     * @param string|array $key
+     */
+    public static function loadParameters($key)
+    {
+        $key = self::load($key);
+        if (!$key instanceof PrivateKey && !$key instanceof PublicKey) {
+            throw new NoKeyLoadedException('The key that was loaded was not a parameter');
+        }
+        return $key;
+    }
+
+    /**
+     * Load the key, assuming a specific format
+     *
+     * @param string $type
+     * @param string $key
+     * @param string $password optional
+     * @return static
+     */
+    public static function loadFormat($type, $key, $password = false)
+    {
+        self::initialize_static_variables();
+
+        $components = false;
+        $format = strtolower($type);
+        if (isset(self::$plugins[static::ALGORITHM]['Keys'][$format])) {
+            $format = self::$plugins[static::ALGORITHM]['Keys'][$format];
+            $components = $format::load($key, $password);
+        }
+
+        if ($components === false) {
+            throw new NoKeyLoadedException('Unable to read key');
+        }
+
+        $components['format'] = $format;
+        $components['secret'] = isset($components['secret']) ? $components['secret'] : '';
+
+        $new = static::onLoad($components);
+        $new->format = $format;
+        return $new instanceof PrivateKey ?
+            $new->withPassword($password) :
+            $new;
+    }
+
+    /**
+     * Loads a private key
+     *
+     * @return PrivateKey
+     * @param string $type
+     * @param string $key
+     * @param string $password optional
+     */
+    public static function loadPrivateKeyFormat($type, $key, $password = false)
+    {
+        $key = self::loadFormat($type, $key, $password);
+        if (!$key instanceof PrivateKey) {
+            throw new NoKeyLoadedException('The key that was loaded was not a private key');
+        }
+        return $key;
+    }
+
+    /**
+     * Loads a public key
+     *
+     * @return PublicKey
+     * @param string $type
+     * @param string $key
+     */
+    public static function loadPublicKeyFormat($type, $key)
+    {
+        $key = self::loadFormat($type, $key);
+        if (!$key instanceof PublicKey) {
+            throw new NoKeyLoadedException('The key that was loaded was not a public key');
+        }
+        return $key;
+    }
+
+    /**
+     * Loads parameters
+     *
+     * @return AsymmetricKey
+     * @param string $type
+     * @param string|array $key
+     */
+    public static function loadParametersFormat($type, $key)
+    {
+        $key = self::loadFormat($type, $key);
+        if (!$key instanceof PrivateKey && !$key instanceof PublicKey) {
+            throw new NoKeyLoadedException('The key that was loaded was not a parameter');
+        }
+        return $key;
+    }
+
+    /**
+     * Validate Plugin
+     *
+     * @param string $format
+     * @param string $type
+     * @param string $method optional
+     * @return mixed
+     */
+    protected static function validatePlugin($format, $type, $method = null)
+    {
+        $type = strtolower($type);
+        if (!isset(self::$plugins[static::ALGORITHM][$format][$type])) {
+            throw new UnsupportedFormatException("$type is not a supported format");
+        }
+        $type = self::$plugins[static::ALGORITHM][$format][$type];
+        if (isset($method) && !method_exists($type, $method)) {
+            throw new UnsupportedFormatException("$type does not implement $method");
+        }
+
+        return $type;
+    }
+
+    /**
+     * Load Plugins
+     *
+     * @param string $format
+     */
+    private static function loadPlugins($format)
+    {
+        if (!isset(self::$plugins[static::ALGORITHM][$format])) {
+            self::$plugins[static::ALGORITHM][$format] = [];
+            foreach (new \DirectoryIterator(__DIR__ . '/../' . static::ALGORITHM . '/Formats/' . $format . '/') as $file) {
+                if ($file->getExtension() != 'php') {
+                    continue;
+                }
+                $name = $file->getBasename('.php');
+                if ($name[0] == '.') {
+                    continue;
+                }
+                $type = 'phpseclib3\Crypt\\' . static::ALGORITHM . '\\Formats\\' . $format . '\\' . $name;
+                $reflect = new \ReflectionClass($type);
+                if ($reflect->isTrait()) {
+                    continue;
+                }
+                self::$plugins[static::ALGORITHM][$format][strtolower($name)] = $type;
+                if ($reflect->hasConstant('IS_INVISIBLE')) {
+                    self::$invisiblePlugins[static::ALGORITHM][] = $type;
+                }
+            }
+        }
+    }
+
+    /**
+     * Returns a list of supported formats.
+     *
+     * @return array
+     */
+    public static function getSupportedKeyFormats()
+    {
+        self::initialize_static_variables();
+
+        return self::$plugins[static::ALGORITHM]['Keys'];
+    }
+
+    /**
+     * Add a fileformat plugin
+     *
+     * The plugin needs to either already be loaded or be auto-loadable.
+     * Loading a plugin whose shortname overwrite an existing shortname will overwrite the old plugin.
+     *
+     * @see self::load()
+     * @param string $fullname
+     * @return bool
+     */
+    public static function addFileFormat($fullname)
+    {
+        self::initialize_static_variables();
+
+        if (class_exists($fullname)) {
+            $meta = new \ReflectionClass($fullname);
+            $shortname = $meta->getShortName();
+            self::$plugins[static::ALGORITHM]['Keys'][strtolower($shortname)] = $fullname;
+            if ($meta->hasConstant('IS_INVISIBLE')) {
+                self::$invisiblePlugins[static::ALGORITHM] = strtolower($name);
+            }
+        }
+    }
+
+    /**
+     * Returns the format of the loaded key.
+     *
+     * If the key that was loaded wasn't in a valid or if the key was auto-generated
+     * with RSA::createKey() then this will throw an exception.
+     *
+     * @see self::load()
+     * @return mixed
+     */
+    public function getLoadedFormat()
+    {
+        if (empty($this->format)) {
+            throw new NoKeyLoadedException('This key was created with createKey - it was not loaded with load. Therefore there is no "loaded format"');
+        }
+
+        $meta = new \ReflectionClass($this->format);
+        return $meta->getShortName();
+    }
+
+    /**
+     * Returns the key's comment
+     *
+     * Not all key formats support comments. If you want to set a comment use toString()
+     *
+     * @return null|string
+     */
+    public function getComment()
+    {
+        return $this->comment;
+    }
+
+    /**
+     * Tests engine validity
+     *
+     */
+    public static function useBestEngine()
+    {
+        static::$engines = [
+            'PHP' => true,
+            'OpenSSL' => extension_loaded('openssl'),
+            // this test can be satisfied by either of the following:
+            // http://php.net/manual/en/book.sodium.php
+            // https://github.com/paragonie/sodium_compat
+            'libsodium' => function_exists('sodium_crypto_sign_keypair')
+        ];
+
+        return static::$engines;
+    }
+
+    /**
+     * Flag to use internal engine only (useful for unit testing)
+     *
+     */
+    public static function useInternalEngine()
+    {
+        static::$engines = [
+            'PHP' => true,
+            'OpenSSL' => false,
+            'libsodium' => false
+        ];
+    }
+
+    /**
+     * __toString() magic method
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->toString('PKCS8');
+    }
+
+    /**
+     * Determines which hashing function should be used
+     *
+     * @param string $hash
+     */
+    public function withHash($hash)
+    {
+        $new = clone $this;
+
+        $new->hash = new Hash($hash);
+        $new->hmac = new Hash($hash);
+
+        return $new;
+    }
+
+    /**
+     * Returns the hash algorithm currently being used
+     *
+     */
+    public function getHash()
+    {
+        return clone $this->hash;
+    }
+
+    /**
+     * Compute the pseudorandom k for signature generation,
+     * using the process specified for deterministic DSA.
+     *
+     * @param string $h1
+     * @return string
+     */
+    protected function computek($h1)
+    {
+        $v = str_repeat("\1", strlen($h1));
+
+        $k = str_repeat("\0", strlen($h1));
+
+        $x = $this->int2octets($this->x);
+        $h1 = $this->bits2octets($h1);
+
+        $this->hmac->setKey($k);
+        $k = $this->hmac->hash($v . "\0" . $x . $h1);
+        $this->hmac->setKey($k);
+        $v = $this->hmac->hash($v);
+        $k = $this->hmac->hash($v . "\1" . $x . $h1);
+        $this->hmac->setKey($k);
+        $v = $this->hmac->hash($v);
+
+        $qlen = $this->q->getLengthInBytes();
+
+        while (true) {
+            $t = '';
+            while (strlen($t) < $qlen) {
+                $v = $this->hmac->hash($v);
+                $t = $t . $v;
+            }
+            $k = $this->bits2int($t);
+
+            if (!$k->equals(self::$zero) && $k->compare($this->q) < 0) {
+                break;
+            }
+            $k = $this->hmac->hash($v . "\0");
+            $this->hmac->setKey($k);
+            $v = $this->hmac->hash($v);
+        }
+
+        return $k;
+    }
+
+    /**
+     * Integer to Octet String
+     *
+     * @param \phpseclib3\Math\BigInteger $v
+     * @return string
+     */
+    private function int2octets($v)
+    {
+        $out = $v->toBytes();
+        $rolen = $this->q->getLengthInBytes();
+        if (strlen($out) < $rolen) {
+            return str_pad($out, $rolen, "\0", STR_PAD_LEFT);
+        } elseif (strlen($out) > $rolen) {
+            return substr($out, -$rolen);
+        } else {
+            return $out;
+        }
+    }
+
+    /**
+     * Bit String to Integer
+     *
+     * @param string $in
+     * @return \phpseclib3\Math\BigInteger
+     */
+    protected function bits2int($in)
+    {
+        $v = new BigInteger($in, 256);
+        $vlen = strlen($in) << 3;
+        $qlen = $this->q->getLength();
+        if ($vlen > $qlen) {
+            return $v->bitwise_rightShift($vlen - $qlen);
+        }
+        return $v;
+    }
+
+    /**
+     * Bit String to Octet String
+     *
+     * @param string $in
+     * @return string
+     */
+    private function bits2octets($in)
+    {
+        $z1 = $this->bits2int($in);
+        $z2 = $z1->subtract($this->q);
+        return $z2->compare(self::$zero) < 0 ?
+            $this->int2octets($z1) :
+            $this->int2octets($z2);
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/BlockCipher.php

+<?php
+
+/**
+ * Base Class for all block ciphers
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @author    Hans-Juergen Petrich <petrich@tronic-media.com>
+ * @copyright 2007 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common;
+
+/**
+ * Base Class for all block cipher classes
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class BlockCipher extends SymmetricKey
+{
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Keys/JWK.php

+<?php
+
+/**
+ * JSON Web Key (RFC7517) Handler
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2015 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Keys;
+
+use phpseclib3\Common\Functions\Strings;
+
+/**
+ * JSON Web Key Formatted Key Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class JWK
+{
+    /**
+     * Break a public or private key down into its constituent components
+     *
+     * @param string $key
+     * @param string $password
+     * @return array
+     */
+    public static function load($key, $password = '')
+    {
+        if (!Strings::is_stringable($key)) {
+            throw new \UnexpectedValueException('Key should be a string - not a ' . gettype($key));
+        }
+
+        $key = preg_replace('#\s#', '', $key); // remove whitespace
+
+        if (PHP_VERSION_ID >= 73000) {
+            $key = json_decode($key, null, 512, JSON_THROW_ON_ERROR);
+        } else {
+            $key = json_decode($key);
+            if (!$key) {
+                throw new \RuntimeException('Unable to decode JSON');
+            }
+        }
+
+        if (isset($key->kty)) {
+            return $key;
+        }
+
+        if (count($key->keys) != 1) {
+            throw new \RuntimeException('Although the JWK key format supports multiple keys phpseclib does not');
+        }
+
+        return $key->keys[0];
+    }
+
+    /**
+     * Wrap a key appropriately
+     *
+     * @return string
+     */
+    protected static function wrapKey(array $key, array $options)
+    {
+        return json_encode(['keys' => [$key + $options]]);
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Keys/OpenSSH.php

+<?php
+
+/**
+ * OpenSSH Key Handler
+ *
+ * PHP version 5
+ *
+ * Place in $HOME/.ssh/authorized_keys
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2015 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Keys;
+
+use phpseclib3\Common\Functions\Strings;
+use phpseclib3\Crypt\AES;
+use phpseclib3\Crypt\Random;
+
+/**
+ * OpenSSH Formatted RSA Key Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class OpenSSH
+{
+    /**
+     * Default comment
+     *
+     * @var string
+     */
+    protected static $comment = 'phpseclib-generated-key';
+
+    /**
+     * Binary key flag
+     *
+     * @var bool
+     */
+    protected static $binary = false;
+
+    /**
+     * Sets the default comment
+     *
+     * @param string $comment
+     */
+    public static function setComment($comment)
+    {
+        self::$comment = str_replace(["\r", "\n"], '', $comment);
+    }
+
+    /**
+     * Break a public or private key down into its constituent components
+     *
+     * $type can be either ssh-dss or ssh-rsa
+     *
+     * @param string $key
+     * @param string $password
+     * @return array
+     */
+    public static function load($key, $password = '')
+    {
+        if (!Strings::is_stringable($key)) {
+            throw new \UnexpectedValueException('Key should be a string - not a ' . gettype($key));
+        }
+
+        // key format is described here:
+        // https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.key?annotate=HEAD
+
+        if (strpos($key, 'BEGIN OPENSSH PRIVATE KEY') !== false) {
+            $key = preg_replace('#(?:^-.*?-[\r\n]*$)|\s#ms', '', $key);
+            $key = Strings::base64_decode($key);
+            $magic = Strings::shift($key, 15);
+            if ($magic != "openssh-key-v1\0") {
+                throw new \RuntimeException('Expected openssh-key-v1');
+            }
+            list($ciphername, $kdfname, $kdfoptions, $numKeys) = Strings::unpackSSH2('sssN', $key);
+            if ($numKeys != 1) {
+                // if we wanted to support multiple keys we could update PublicKeyLoader to preview what the # of keys
+                // would be; it'd then call Common\Keys\OpenSSH.php::load() and get the paddedKey. it'd then pass
+                // that to the appropriate key loading parser $numKey times or something
+                throw new \RuntimeException('Although the OpenSSH private key format supports multiple keys phpseclib does not');
+            }
+            switch ($ciphername) {
+                case 'none':
+                    break;
+                case 'aes256-ctr':
+                    if ($kdfname != 'bcrypt') {
+                        throw new \RuntimeException('Only the bcrypt kdf is supported (' . $kdfname . ' encountered)');
+                    }
+                    list($salt, $rounds) = Strings::unpackSSH2('sN', $kdfoptions);
+                    $crypto = new AES('ctr');
+                    //$crypto->setKeyLength(256);
+                    //$crypto->disablePadding();
+                    $crypto->setPassword($password, 'bcrypt', $salt, $rounds, 32);
+                    break;
+                default:
+                    throw new \RuntimeException('The only supported cipherse are: none, aes256-ctr (' . $ciphername . ' is being used)');
+            }
+
+            list($publicKey, $paddedKey) = Strings::unpackSSH2('ss', $key);
+            list($type) = Strings::unpackSSH2('s', $publicKey);
+            if (isset($crypto)) {
+                $paddedKey = $crypto->decrypt($paddedKey);
+            }
+            list($checkint1, $checkint2) = Strings::unpackSSH2('NN', $paddedKey);
+            // any leftover bytes in $paddedKey are for padding? but they should be sequential bytes. eg. 1, 2, 3, etc.
+            if ($checkint1 != $checkint2) {
+                throw new \RuntimeException('The two checkints do not match');
+            }
+            self::checkType($type);
+
+            return compact('type', 'publicKey', 'paddedKey');
+        }
+
+        $parts = explode(' ', $key, 3);
+
+        if (!isset($parts[1])) {
+            $key = base64_decode($parts[0]);
+            $comment = false;
+        } else {
+            $asciiType = $parts[0];
+            self::checkType($parts[0]);
+            $key = base64_decode($parts[1]);
+            $comment = isset($parts[2]) ? $parts[2] : false;
+        }
+        if ($key === false) {
+            throw new \UnexpectedValueException('Key should be a string - not a ' . gettype($key));
+        }
+
+        list($type) = Strings::unpackSSH2('s', $key);
+        self::checkType($type);
+        if (isset($asciiType) && $asciiType != $type) {
+            throw new \RuntimeException('Two different types of keys are claimed: ' . $asciiType . ' and ' . $type);
+        }
+        if (strlen($key) <= 4) {
+            throw new \UnexpectedValueException('Key appears to be malformed');
+        }
+
+        $publicKey = $key;
+
+        return compact('type', 'publicKey', 'comment');
+    }
+
+    /**
+     * Toggle between binary and printable keys
+     *
+     * Printable keys are what are generated by default. These are the ones that go in
+     * $HOME/.ssh/authorized_key.
+     *
+     * @param bool $enabled
+     */
+    public static function setBinaryOutput($enabled)
+    {
+        self::$binary = $enabled;
+    }
+
+    /**
+     * Checks to see if the type is valid
+     *
+     * @param string $candidate
+     */
+    private static function checkType($candidate)
+    {
+        if (!in_array($candidate, static::$types)) {
+            throw new \RuntimeException("The key type ($candidate) is not equal to: " . implode(',', static::$types));
+        }
+    }
+
+    /**
+     * Wrap a private key appropriately
+     *
+     * @param string $publicKey
+     * @param string $privateKey
+     * @param string $password
+     * @param array $options
+     * @return string
+     */
+    protected static function wrapPrivateKey($publicKey, $privateKey, $password, $options)
+    {
+        list(, $checkint) = unpack('N', Random::string(4));
+
+        $comment = isset($options['comment']) ? $options['comment'] : self::$comment;
+        $paddedKey = Strings::packSSH2('NN', $checkint, $checkint) .
+                     $privateKey .
+                     Strings::packSSH2('s', $comment);
+
+        $usesEncryption = !empty($password) && is_string($password);
+
+        /*
+           from http://tools.ietf.org/html/rfc4253#section-6 :
+
+           Note that the length of the concatenation of 'packet_length',
+           'padding_length', 'payload', and 'random padding' MUST be a multiple
+           of the cipher block size or 8, whichever is larger.
+         */
+        $blockSize = $usesEncryption ? 16 : 8;
+        $paddingLength = (($blockSize - 1) * strlen($paddedKey)) % $blockSize;
+        for ($i = 1; $i <= $paddingLength; $i++) {
+            $paddedKey .= chr($i);
+        }
+        if (!$usesEncryption) {
+            $key = Strings::packSSH2('sssNss', 'none', 'none', '', 1, $publicKey, $paddedKey);
+        } else {
+            $rounds = isset($options['rounds']) ? $options['rounds'] : 16;
+            $salt = Random::string(16);
+            $kdfoptions = Strings::packSSH2('sN', $salt, $rounds);
+            $crypto = new AES('ctr');
+            $crypto->setPassword($password, 'bcrypt', $salt, $rounds, 32);
+            $paddedKey = $crypto->encrypt($paddedKey);
+            $key = Strings::packSSH2('sssNss', 'aes256-ctr', 'bcrypt', $kdfoptions, 1, $publicKey, $paddedKey);
+        }
+        $key = "openssh-key-v1\0$key";
+
+        return "-----BEGIN OPENSSH PRIVATE KEY-----\n" .
+               chunk_split(Strings::base64_encode($key), 70, "\n") .
+               "-----END OPENSSH PRIVATE KEY-----\n";
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Keys/PKCS.php

+<?php
+
+/**
+ * PKCS Formatted Key Handler
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2015 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Keys;
+
+/**
+ * PKCS1 Formatted Key Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class PKCS
+{
+    /**
+     * Auto-detect the format
+     */
+    const MODE_ANY = 0;
+    /**
+     * Require base64-encoded PEM's be supplied
+     */
+    const MODE_PEM = 1;
+    /**
+     * Require raw DER's be supplied
+     */
+    const MODE_DER = 2;
+    /**#@-*/
+
+    /**
+     * Is the key a base-64 encoded PEM, DER or should it be auto-detected?
+     *
+     * @var int
+     */
+    protected static $format = self::MODE_ANY;
+
+    /**
+     * Require base64-encoded PEM's be supplied
+     *
+     */
+    public static function requirePEM()
+    {
+        self::$format = self::MODE_PEM;
+    }
+
+    /**
+     * Require raw DER's be supplied
+     *
+     */
+    public static function requireDER()
+    {
+        self::$format = self::MODE_DER;
+    }
+
+    /**
+     * Accept any format and auto detect the format
+     *
+     * This is the default setting
+     *
+     */
+    public static function requireAny()
+    {
+        self::$format = self::MODE_ANY;
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Keys/PKCS1.php

+<?php
+
+/**
+ * PKCS1 Formatted Key Handler
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2015 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Keys;
+
+use phpseclib3\Common\Functions\Strings;
+use phpseclib3\Crypt\AES;
+use phpseclib3\Crypt\DES;
+use phpseclib3\Crypt\Random;
+use phpseclib3\Crypt\TripleDES;
+use phpseclib3\Exception\UnsupportedAlgorithmException;
+use phpseclib3\File\ASN1;
+
+/**
+ * PKCS1 Formatted Key Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class PKCS1 extends PKCS
+{
+    /**
+     * Default encryption algorithm
+     *
+     * @var string
+     */
+    private static $defaultEncryptionAlgorithm = 'AES-128-CBC';
+
+    /**
+     * Sets the default encryption algorithm
+     *
+     * @param string $algo
+     */
+    public static function setEncryptionAlgorithm($algo)
+    {
+        self::$defaultEncryptionAlgorithm = $algo;
+    }
+
+    /**
+     * Returns the mode constant corresponding to the mode string
+     *
+     * @param string $mode
+     * @return int
+     * @throws \UnexpectedValueException if the block cipher mode is unsupported
+     */
+    private static function getEncryptionMode($mode)
+    {
+        switch ($mode) {
+            case 'CBC':
+            case 'ECB':
+            case 'CFB':
+            case 'OFB':
+            case 'CTR':
+                return $mode;
+        }
+        throw new \UnexpectedValueException('Unsupported block cipher mode of operation');
+    }
+
+    /**
+     * Returns a cipher object corresponding to a string
+     *
+     * @param string $algo
+     * @return string
+     * @throws \UnexpectedValueException if the encryption algorithm is unsupported
+     */
+    private static function getEncryptionObject($algo)
+    {
+        $modes = '(CBC|ECB|CFB|OFB|CTR)';
+        switch (true) {
+            case preg_match("#^AES-(128|192|256)-$modes$#", $algo, $matches):
+                $cipher = new AES(self::getEncryptionMode($matches[2]));
+                $cipher->setKeyLength($matches[1]);
+                return $cipher;
+            case preg_match("#^DES-EDE3-$modes$#", $algo, $matches):
+                return new TripleDES(self::getEncryptionMode($matches[1]));
+            case preg_match("#^DES-$modes$#", $algo, $matches):
+                return new DES(self::getEncryptionMode($matches[1]));
+            default:
+                throw new UnsupportedAlgorithmException($algo . ' is not a supported algorithm');
+        }
+    }
+
+    /**
+     * Generate a symmetric key for PKCS#1 keys
+     *
+     * @param string $password
+     * @param string $iv
+     * @param int $length
+     * @return string
+     */
+    private static function generateSymmetricKey($password, $iv, $length)
+    {
+        $symkey = '';
+        $iv = substr($iv, 0, 8);
+        while (strlen($symkey) < $length) {
+            $symkey .= md5($symkey . $password . $iv, true);
+        }
+        return substr($symkey, 0, $length);
+    }
+
+    /**
+     * Break a public or private key down into its constituent components
+     *
+     * @param string $key
+     * @param string $password optional
+     * @return array
+     */
+    protected static function load($key, $password)
+    {
+        if (!Strings::is_stringable($key)) {
+            throw new \UnexpectedValueException('Key should be a string - not a ' . gettype($key));
+        }
+
+        /* Although PKCS#1 proposes a format that public and private keys can use, encrypting them is
+           "outside the scope" of PKCS#1.  PKCS#1 then refers you to PKCS#12 and PKCS#15 if you're wanting to
+           protect private keys, however, that's not what OpenSSL* does.  OpenSSL protects private keys by adding
+           two new "fields" to the key - DEK-Info and Proc-Type.  These fields are discussed here:
+
+           http://tools.ietf.org/html/rfc1421#section-4.6.1.1
+           http://tools.ietf.org/html/rfc1421#section-4.6.1.3
+
+           DES-EDE3-CBC as an algorithm, however, is not discussed anywhere, near as I can tell.
+           DES-CBC and DES-EDE are discussed in RFC1423, however, DES-EDE3-CBC isn't, nor is its key derivation
+           function.  As is, the definitive authority on this encoding scheme isn't the IETF but rather OpenSSL's
+           own implementation.  ie. the implementation *is* the standard and any bugs that may exist in that
+           implementation are part of the standard, as well.
+
+           * OpenSSL is the de facto standard.  It's utilized by OpenSSH and other projects */
+        if (preg_match('#DEK-Info: (.+),(.+)#', $key, $matches)) {
+            $iv = Strings::hex2bin(trim($matches[2]));
+            // remove the Proc-Type / DEK-Info sections as they're no longer needed
+            $key = preg_replace('#^(?:Proc-Type|DEK-Info): .*#m', '', $key);
+            $ciphertext = ASN1::extractBER($key);
+            if ($ciphertext === false) {
+                $ciphertext = $key;
+            }
+            $crypto = self::getEncryptionObject($matches[1]);
+            $crypto->setKey(self::generateSymmetricKey($password, $iv, $crypto->getKeyLength() >> 3));
+            $crypto->setIV($iv);
+            $key = $crypto->decrypt($ciphertext);
+        } else {
+            if (self::$format != self::MODE_DER) {
+                $decoded = ASN1::extractBER($key);
+                if ($decoded !== false) {
+                    $key = $decoded;
+                } elseif (self::$format == self::MODE_PEM) {
+                    throw new \UnexpectedValueException('Expected base64-encoded PEM format but was unable to decode base64 text');
+                }
+            }
+        }
+
+        return $key;
+    }
+
+    /**
+     * Wrap a private key appropriately
+     *
+     * @param string $key
+     * @param string $type
+     * @param string $password
+     * @param array $options optional
+     * @return string
+     */
+    protected static function wrapPrivateKey($key, $type, $password, array $options = [])
+    {
+        if (empty($password) || !is_string($password)) {
+            return "-----BEGIN $type PRIVATE KEY-----\r\n" .
+                   chunk_split(Strings::base64_encode($key), 64) .
+                   "-----END $type PRIVATE KEY-----";
+        }
+
+        $encryptionAlgorithm = isset($options['encryptionAlgorithm']) ? $options['encryptionAlgorithm'] : self::$defaultEncryptionAlgorithm;
+
+        $cipher = self::getEncryptionObject($encryptionAlgorithm);
+        $iv = Random::string($cipher->getBlockLength() >> 3);
+        $cipher->setKey(self::generateSymmetricKey($password, $iv, $cipher->getKeyLength() >> 3));
+        $cipher->setIV($iv);
+        $iv = strtoupper(Strings::bin2hex($iv));
+        return "-----BEGIN $type PRIVATE KEY-----\r\n" .
+               "Proc-Type: 4,ENCRYPTED\r\n" .
+               "DEK-Info: " . $encryptionAlgorithm . ",$iv\r\n" .
+               "\r\n" .
+               chunk_split(Strings::base64_encode($cipher->encrypt($key)), 64) .
+               "-----END $type PRIVATE KEY-----";
+    }
+
+    /**
+     * Wrap a public key appropriately
+     *
+     * @param string $key
+     * @param string $type
+     * @return string
+     */
+    protected static function wrapPublicKey($key, $type)
+    {
+        return "-----BEGIN $type PUBLIC KEY-----\r\n" .
+               chunk_split(Strings::base64_encode($key), 64) .
+               "-----END $type PUBLIC KEY-----";
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Keys/PKCS8.php

+<?php
+
+/**
+ * PKCS#8 Formatted Key Handler
+ *
+ * PHP version 5
+ *
+ * Used by PHP's openssl_public_encrypt() and openssl's rsautl (when -pubin is set)
+ *
+ * Processes keys with the following headers:
+ *
+ * -----BEGIN ENCRYPTED PRIVATE KEY-----
+ * -----BEGIN PRIVATE KEY-----
+ * -----BEGIN PUBLIC KEY-----
+ *
+ * Analogous to ssh-keygen's pkcs8 format (as specified by -m). Although PKCS8
+ * is specific to private keys it's basically creating a DER-encoded wrapper
+ * for keys. This just extends that same concept to public keys (much like ssh-keygen)
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2015 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Keys;
+
+use phpseclib3\Common\Functions\Strings;
+use phpseclib3\Crypt\AES;
+use phpseclib3\Crypt\DES;
+use phpseclib3\Crypt\Random;
+use phpseclib3\Crypt\RC2;
+use phpseclib3\Crypt\RC4;
+use phpseclib3\Crypt\TripleDES;
+use phpseclib3\Exception\InsufficientSetupException;
+use phpseclib3\Exception\UnsupportedAlgorithmException;
+use phpseclib3\File\ASN1;
+use phpseclib3\File\ASN1\Maps;
+
+/**
+ * PKCS#8 Formatted Key Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class PKCS8 extends PKCS
+{
+    /**
+     * Default encryption algorithm
+     *
+     * @var string
+     */
+    private static $defaultEncryptionAlgorithm = 'id-PBES2';
+
+    /**
+     * Default encryption scheme
+     *
+     * Only used when defaultEncryptionAlgorithm is id-PBES2
+     *
+     * @var string
+     */
+    private static $defaultEncryptionScheme = 'aes128-CBC-PAD';
+
+    /**
+     * Default PRF
+     *
+     * Only used when defaultEncryptionAlgorithm is id-PBES2
+     *
+     * @var string
+     */
+    private static $defaultPRF = 'id-hmacWithSHA256';
+
+    /**
+     * Default Iteration Count
+     *
+     * @var int
+     */
+    private static $defaultIterationCount = 2048;
+
+    /**
+     * OIDs loaded
+     *
+     * @var bool
+     */
+    private static $oidsLoaded = false;
+
+    /**
+     * Sets the default encryption algorithm
+     *
+     * @param string $algo
+     */
+    public static function setEncryptionAlgorithm($algo)
+    {
+        self::$defaultEncryptionAlgorithm = $algo;
+    }
+
+    /**
+     * Sets the default encryption algorithm for PBES2
+     *
+     * @param string $algo
+     */
+    public static function setEncryptionScheme($algo)
+    {
+        self::$defaultEncryptionScheme = $algo;
+    }
+
+    /**
+     * Sets the iteration count
+     *
+     * @param int $count
+     */
+    public static function setIterationCount($count)
+    {
+        self::$defaultIterationCount = $count;
+    }
+
+    /**
+     * Sets the PRF for PBES2
+     *
+     * @param string $algo
+     */
+    public static function setPRF($algo)
+    {
+        self::$defaultPRF = $algo;
+    }
+
+    /**
+     * Returns a SymmetricKey object based on a PBES1 $algo
+     *
+     * @return \phpseclib3\Crypt\Common\SymmetricKey
+     * @param string $algo
+     */
+    private static function getPBES1EncryptionObject($algo)
+    {
+        $algo = preg_match('#^pbeWith(?:MD2|MD5|SHA1|SHA)And(.*?)-CBC$#', $algo, $matches) ?
+            $matches[1] :
+            substr($algo, 13); // strlen('pbeWithSHAAnd') == 13
+
+        switch ($algo) {
+            case 'DES':
+                $cipher = new DES('cbc');
+                break;
+            case 'RC2':
+                $cipher = new RC2('cbc');
+                break;
+            case '3-KeyTripleDES':
+                $cipher = new TripleDES('cbc');
+                break;
+            case '2-KeyTripleDES':
+                $cipher = new TripleDES('cbc');
+                $cipher->setKeyLength(128);
+                break;
+            case '128BitRC2':
+                $cipher = new RC2('cbc');
+                $cipher->setKeyLength(128);
+                break;
+            case '40BitRC2':
+                $cipher = new RC2('cbc');
+                $cipher->setKeyLength(40);
+                break;
+            case '128BitRC4':
+                $cipher = new RC4();
+                $cipher->setKeyLength(128);
+                break;
+            case '40BitRC4':
+                $cipher = new RC4();
+                $cipher->setKeyLength(40);
+                break;
+            default:
+                throw new UnsupportedAlgorithmException("$algo is not a supported algorithm");
+        }
+
+        return $cipher;
+    }
+
+    /**
+     * Returns a hash based on a PBES1 $algo
+     *
+     * @return string
+     * @param string $algo
+     */
+    private static function getPBES1Hash($algo)
+    {
+        if (preg_match('#^pbeWith(MD2|MD5|SHA1|SHA)And.*?-CBC$#', $algo, $matches)) {
+            return $matches[1] == 'SHA' ? 'sha1' : $matches[1];
+        }
+
+        return 'sha1';
+    }
+
+    /**
+     * Returns a KDF baesd on a PBES1 $algo
+     *
+     * @return string
+     * @param string $algo
+     */
+    private static function getPBES1KDF($algo)
+    {
+        switch ($algo) {
+            case 'pbeWithMD2AndDES-CBC':
+            case 'pbeWithMD2AndRC2-CBC':
+            case 'pbeWithMD5AndDES-CBC':
+            case 'pbeWithMD5AndRC2-CBC':
+            case 'pbeWithSHA1AndDES-CBC':
+            case 'pbeWithSHA1AndRC2-CBC':
+                return 'pbkdf1';
+        }
+
+        return 'pkcs12';
+    }
+
+    /**
+     * Returns a SymmetricKey object baesd on a PBES2 $algo
+     *
+     * @return SymmetricKey
+     * @param string $algo
+     */
+    private static function getPBES2EncryptionObject($algo)
+    {
+        switch ($algo) {
+            case 'desCBC':
+                $cipher = new TripleDES('cbc');
+                break;
+            case 'des-EDE3-CBC':
+                $cipher = new TripleDES('cbc');
+                break;
+            case 'rc2CBC':
+                $cipher = new RC2('cbc');
+                // in theory this can be changed
+                $cipher->setKeyLength(128);
+                break;
+            case 'rc5-CBC-PAD':
+                throw new UnsupportedAlgorithmException('rc5-CBC-PAD is not supported for PBES2 PKCS#8 keys');
+            case 'aes128-CBC-PAD':
+            case 'aes192-CBC-PAD':
+            case 'aes256-CBC-PAD':
+                $cipher = new AES('cbc');
+                $cipher->setKeyLength(substr($algo, 3, 3));
+                break;
+            default:
+                throw new UnsupportedAlgorithmException("$algo is not supported");
+        }
+
+        return $cipher;
+    }
+
+    /**
+     * Initialize static variables
+     *
+     */
+    private static function initialize_static_variables()
+    {
+        if (!isset(static::$childOIDsLoaded)) {
+            throw new InsufficientSetupException('This class should not be called directly');
+        }
+
+        if (!static::$childOIDsLoaded) {
+            ASN1::loadOIDs(is_array(static::OID_NAME) ?
+                array_combine(static::OID_NAME, static::OID_VALUE) :
+                [static::OID_NAME => static::OID_VALUE]);
+            static::$childOIDsLoaded = true;
+        }
+        if (!self::$oidsLoaded) {
+            // from https://tools.ietf.org/html/rfc2898
+            ASN1::loadOIDs([
+               // PBES1 encryption schemes
+               'pbeWithMD2AndDES-CBC' => '1.2.840.113549.1.5.1',
+               'pbeWithMD2AndRC2-CBC' => '1.2.840.113549.1.5.4',
+               'pbeWithMD5AndDES-CBC' => '1.2.840.113549.1.5.3',
+               'pbeWithMD5AndRC2-CBC' => '1.2.840.113549.1.5.6',
+               'pbeWithSHA1AndDES-CBC' => '1.2.840.113549.1.5.10',
+               'pbeWithSHA1AndRC2-CBC' => '1.2.840.113549.1.5.11',
+
+               // from PKCS#12:
+               // https://tools.ietf.org/html/rfc7292
+               'pbeWithSHAAnd128BitRC4' => '1.2.840.113549.1.12.1.1',
+               'pbeWithSHAAnd40BitRC4' => '1.2.840.113549.1.12.1.2',
+               'pbeWithSHAAnd3-KeyTripleDES-CBC' => '1.2.840.113549.1.12.1.3',
+               'pbeWithSHAAnd2-KeyTripleDES-CBC' => '1.2.840.113549.1.12.1.4',
+               'pbeWithSHAAnd128BitRC2-CBC' => '1.2.840.113549.1.12.1.5',
+               'pbeWithSHAAnd40BitRC2-CBC' => '1.2.840.113549.1.12.1.6',
+
+               'id-PBKDF2' => '1.2.840.113549.1.5.12',
+               'id-PBES2' => '1.2.840.113549.1.5.13',
+               'id-PBMAC1' => '1.2.840.113549.1.5.14',
+
+               // from PKCS#5 v2.1:
+               // http://www.rsa.com/rsalabs/pkcs/files/h11302-wp-pkcs5v2-1-password-based-cryptography-standard.pdf
+               'id-hmacWithSHA1' => '1.2.840.113549.2.7',
+               'id-hmacWithSHA224' => '1.2.840.113549.2.8',
+               'id-hmacWithSHA256' => '1.2.840.113549.2.9',
+               'id-hmacWithSHA384' => '1.2.840.113549.2.10',
+               'id-hmacWithSHA512' => '1.2.840.113549.2.11',
+               'id-hmacWithSHA512-224' => '1.2.840.113549.2.12',
+               'id-hmacWithSHA512-256' => '1.2.840.113549.2.13',
+
+               'desCBC'       => '1.3.14.3.2.7',
+               'des-EDE3-CBC' => '1.2.840.113549.3.7',
+               'rc2CBC' => '1.2.840.113549.3.2',
+               'rc5-CBC-PAD' => '1.2.840.113549.3.9',
+
+               'aes128-CBC-PAD' => '2.16.840.1.101.3.4.1.2',
+               'aes192-CBC-PAD' => '2.16.840.1.101.3.4.1.22',
+               'aes256-CBC-PAD' => '2.16.840.1.101.3.4.1.42'
+            ]);
+            self::$oidsLoaded = true;
+        }
+    }
+
+    /**
+     * Break a public or private key down into its constituent components
+     *
+     * @param string $key
+     * @param string $password optional
+     * @return array
+     */
+    protected static function load($key, $password = '')
+    {
+        $decoded = self::preParse($key);
+
+        $meta = [];
+
+        $decrypted = ASN1::asn1map($decoded[0], Maps\EncryptedPrivateKeyInfo::MAP);
+        if (strlen($password) && is_array($decrypted)) {
+            $algorithm = $decrypted['encryptionAlgorithm']['algorithm'];
+            switch ($algorithm) {
+                // PBES1
+                case 'pbeWithMD2AndDES-CBC':
+                case 'pbeWithMD2AndRC2-CBC':
+                case 'pbeWithMD5AndDES-CBC':
+                case 'pbeWithMD5AndRC2-CBC':
+                case 'pbeWithSHA1AndDES-CBC':
+                case 'pbeWithSHA1AndRC2-CBC':
+                case 'pbeWithSHAAnd3-KeyTripleDES-CBC':
+                case 'pbeWithSHAAnd2-KeyTripleDES-CBC':
+                case 'pbeWithSHAAnd128BitRC2-CBC':
+                case 'pbeWithSHAAnd40BitRC2-CBC':
+                case 'pbeWithSHAAnd128BitRC4':
+                case 'pbeWithSHAAnd40BitRC4':
+                    $cipher = self::getPBES1EncryptionObject($algorithm);
+                    $hash = self::getPBES1Hash($algorithm);
+                    $kdf = self::getPBES1KDF($algorithm);
+
+                    $meta['meta']['algorithm'] = $algorithm;
+
+                    $temp = ASN1::decodeBER($decrypted['encryptionAlgorithm']['parameters']);
+                    if (!$temp) {
+                        throw new \RuntimeException('Unable to decode BER');
+                    }
+                    extract(ASN1::asn1map($temp[0], Maps\PBEParameter::MAP));
+                    $iterationCount = (int) $iterationCount->toString();
+                    $cipher->setPassword($password, $kdf, $hash, $salt, $iterationCount);
+                    $key = $cipher->decrypt($decrypted['encryptedData']);
+                    $decoded = ASN1::decodeBER($key);
+                    if (!$decoded) {
+                        throw new \RuntimeException('Unable to decode BER 2');
+                    }
+
+                    break;
+                case 'id-PBES2':
+                    $meta['meta']['algorithm'] = $algorithm;
+
+                    $temp = ASN1::decodeBER($decrypted['encryptionAlgorithm']['parameters']);
+                    if (!$temp) {
+                        throw new \RuntimeException('Unable to decode BER');
+                    }
+                    $temp = ASN1::asn1map($temp[0], Maps\PBES2params::MAP);
+                    extract($temp);
+
+                    $cipher = self::getPBES2EncryptionObject($encryptionScheme['algorithm']);
+                    $meta['meta']['cipher'] = $encryptionScheme['algorithm'];
+
+                    $temp = ASN1::decodeBER($decrypted['encryptionAlgorithm']['parameters']);
+                    if (!$temp) {
+                        throw new \RuntimeException('Unable to decode BER');
+                    }
+                    $temp = ASN1::asn1map($temp[0], Maps\PBES2params::MAP);
+                    extract($temp);
+
+                    if (!$cipher instanceof RC2) {
+                        $cipher->setIV($encryptionScheme['parameters']['octetString']);
+                    } else {
+                        $temp = ASN1::decodeBER($encryptionScheme['parameters']);
+                        if (!$temp) {
+                            throw new \RuntimeException('Unable to decode BER');
+                        }
+                        extract(ASN1::asn1map($temp[0], Maps\RC2CBCParameter::MAP));
+                        $effectiveKeyLength = (int) $rc2ParametersVersion->toString();
+                        switch ($effectiveKeyLength) {
+                            case 160:
+                                $effectiveKeyLength = 40;
+                                break;
+                            case 120:
+                                $effectiveKeyLength = 64;
+                                break;
+                            case 58:
+                                $effectiveKeyLength = 128;
+                                break;
+                            //default: // should be >= 256
+                        }
+                        $cipher->setIV($iv);
+                        $cipher->setKeyLength($effectiveKeyLength);
+                    }
+
+                    $meta['meta']['keyDerivationFunc'] = $keyDerivationFunc['algorithm'];
+                    switch ($keyDerivationFunc['algorithm']) {
+                        case 'id-PBKDF2':
+                            $temp = ASN1::decodeBER($keyDerivationFunc['parameters']);
+                            if (!$temp) {
+                                throw new \RuntimeException('Unable to decode BER');
+                            }
+                            $prf = ['algorithm' => 'id-hmacWithSHA1'];
+                            $params = ASN1::asn1map($temp[0], Maps\PBKDF2params::MAP);
+                            extract($params);
+                            $meta['meta']['prf'] = $prf['algorithm'];
+                            $hash = str_replace('-', '/', substr($prf['algorithm'], 11));
+                            $params = [
+                                $password,
+                                'pbkdf2',
+                                $hash,
+                                $salt,
+                                (int) $iterationCount->toString()
+                            ];
+                            if (isset($keyLength)) {
+                                $params[] = (int) $keyLength->toString();
+                            }
+                            $cipher->setPassword(...$params);
+                            $key = $cipher->decrypt($decrypted['encryptedData']);
+                            $decoded = ASN1::decodeBER($key);
+                            if (!$decoded) {
+                                throw new \RuntimeException('Unable to decode BER 3');
+                            }
+                            break;
+                        default:
+                            throw new UnsupportedAlgorithmException('Only PBKDF2 is supported for PBES2 PKCS#8 keys');
+                    }
+                    break;
+                case 'id-PBMAC1':
+                    //$temp = ASN1::decodeBER($decrypted['encryptionAlgorithm']['parameters']);
+                    //$value = ASN1::asn1map($temp[0], Maps\PBMAC1params::MAP);
+                    // since i can't find any implementation that does PBMAC1 it is unsupported
+                    throw new UnsupportedAlgorithmException('Only PBES1 and PBES2 PKCS#8 keys are supported.');
+                // at this point we'll assume that the key conforms to PublicKeyInfo
+            }
+        }
+
+        $private = ASN1::asn1map($decoded[0], Maps\OneAsymmetricKey::MAP);
+        if (is_array($private)) {
+            if (isset($private['privateKeyAlgorithm']['parameters']) && !$private['privateKeyAlgorithm']['parameters'] instanceof ASN1\Element && isset($decoded[0]['content'][1]['content'][1])) {
+                $temp = $decoded[0]['content'][1]['content'][1];
+                $private['privateKeyAlgorithm']['parameters'] = new ASN1\Element(substr($key, $temp['start'], $temp['length']));
+            }
+            if (is_array(static::OID_NAME)) {
+                if (!in_array($private['privateKeyAlgorithm']['algorithm'], static::OID_NAME)) {
+                    throw new UnsupportedAlgorithmException($private['privateKeyAlgorithm']['algorithm'] . ' is not a supported key type');
+                }
+            } else {
+                if ($private['privateKeyAlgorithm']['algorithm'] != static::OID_NAME) {
+                    throw new UnsupportedAlgorithmException('Only ' . static::OID_NAME . ' keys are supported; this is a ' . $private['privateKeyAlgorithm']['algorithm'] . ' key');
+                }
+            }
+            if (isset($private['publicKey'])) {
+                if ($private['publicKey'][0] != "\0") {
+                    throw new \UnexpectedValueException('The first byte of the public key should be null - not ' . bin2hex($private['publicKey'][0]));
+                }
+                $private['publicKey'] = substr($private['publicKey'], 1);
+            }
+            return $private + $meta;
+        }
+
+        // EncryptedPrivateKeyInfo and PublicKeyInfo have largely identical "signatures". the only difference
+        // is that the former has an octet string and the later has a bit string. the first byte of a bit
+        // string represents the number of bits in the last byte that are to be ignored but, currently,
+        // bit strings wanting a non-zero amount of bits trimmed are not supported
+        $public = ASN1::asn1map($decoded[0], Maps\PublicKeyInfo::MAP);
+
+        if (is_array($public)) {
+            if ($public['publicKey'][0] != "\0") {
+                throw new \UnexpectedValueException('The first byte of the public key should be null - not ' . bin2hex($public['publicKey'][0]));
+            }
+            if (is_array(static::OID_NAME)) {
+                if (!in_array($public['publicKeyAlgorithm']['algorithm'], static::OID_NAME)) {
+                    throw new UnsupportedAlgorithmException($public['publicKeyAlgorithm']['algorithm'] . ' is not a supported key type');
+                }
+            } else {
+                if ($public['publicKeyAlgorithm']['algorithm'] != static::OID_NAME) {
+                    throw new UnsupportedAlgorithmException('Only ' . static::OID_NAME . ' keys are supported; this is a ' . $public['publicKeyAlgorithm']['algorithm'] . ' key');
+                }
+            }
+            if (isset($public['publicKeyAlgorithm']['parameters']) && !$public['publicKeyAlgorithm']['parameters'] instanceof ASN1\Element && isset($decoded[0]['content'][0]['content'][1])) {
+                $temp = $decoded[0]['content'][0]['content'][1];
+                $public['publicKeyAlgorithm']['parameters'] = new ASN1\Element(substr($key, $temp['start'], $temp['length']));
+            }
+            $public['publicKey'] = substr($public['publicKey'], 1);
+            return $public;
+        }
+
+        throw new \RuntimeException('Unable to parse using either OneAsymmetricKey or PublicKeyInfo ASN1 maps');
+    }
+
+    /**
+     * Wrap a private key appropriately
+     *
+     * @param string $key
+     * @param string $attr
+     * @param mixed $params
+     * @param string $password
+     * @param string $oid optional
+     * @param string $publicKey optional
+     * @param array $options optional
+     * @return string
+     */
+    protected static function wrapPrivateKey($key, $attr, $params, $password, $oid = null, $publicKey = '', array $options = [])
+    {
+        self::initialize_static_variables();
+
+        $key = [
+            'version' => 'v1',
+            'privateKeyAlgorithm' => [
+                'algorithm' => is_string(static::OID_NAME) ? static::OID_NAME : $oid
+             ],
+            'privateKey' => $key
+        ];
+        if ($oid != 'id-Ed25519' && $oid != 'id-Ed448') {
+            $key['privateKeyAlgorithm']['parameters'] = $params;
+        }
+        if (!empty($attr)) {
+            $key['attributes'] = $attr;
+        }
+        if (!empty($publicKey)) {
+            $key['version'] = 'v2';
+            $key['publicKey'] = $publicKey;
+        }
+        $key = ASN1::encodeDER($key, Maps\OneAsymmetricKey::MAP);
+        if (!empty($password) && is_string($password)) {
+            $salt = Random::string(8);
+
+            $iterationCount = isset($options['iterationCount']) ? $options['iterationCount'] : self::$defaultIterationCount;
+            $encryptionAlgorithm = isset($options['encryptionAlgorithm']) ? $options['encryptionAlgorithm'] : self::$defaultEncryptionAlgorithm;
+            $encryptionScheme = isset($options['encryptionScheme']) ? $options['encryptionScheme'] : self::$defaultEncryptionScheme;
+            $prf = isset($options['PRF']) ? $options['PRF'] : self::$defaultPRF;
+
+            if ($encryptionAlgorithm == 'id-PBES2') {
+                $crypto = self::getPBES2EncryptionObject($encryptionScheme);
+                $hash = str_replace('-', '/', substr($prf, 11));
+                $kdf = 'pbkdf2';
+                $iv = Random::string($crypto->getBlockLength() >> 3);
+
+                $PBKDF2params = [
+                    'salt' => $salt,
+                    'iterationCount' => $iterationCount,
+                    'prf' => ['algorithm' => $prf, 'parameters' => null]
+                ];
+                $PBKDF2params = ASN1::encodeDER($PBKDF2params, Maps\PBKDF2params::MAP);
+
+                if (!$crypto instanceof RC2) {
+                    $params = ['octetString' => $iv];
+                } else {
+                    $params = [
+                        'rc2ParametersVersion' => 58,
+                        'iv' => $iv
+                    ];
+                    $params = ASN1::encodeDER($params, Maps\RC2CBCParameter::MAP);
+                    $params = new ASN1\Element($params);
+                }
+
+                $params = [
+                    'keyDerivationFunc' => [
+                        'algorithm' => 'id-PBKDF2',
+                        'parameters' => new ASN1\Element($PBKDF2params)
+                    ],
+                    'encryptionScheme' => [
+                        'algorithm' => $encryptionScheme,
+                        'parameters' => $params
+                    ]
+                ];
+                $params = ASN1::encodeDER($params, Maps\PBES2params::MAP);
+
+                $crypto->setIV($iv);
+            } else {
+                $crypto = self::getPBES1EncryptionObject($encryptionAlgorithm);
+                $hash = self::getPBES1Hash($encryptionAlgorithm);
+                $kdf = self::getPBES1KDF($encryptionAlgorithm);
+
+                $params = [
+                    'salt' => $salt,
+                    'iterationCount' => $iterationCount
+                ];
+                $params = ASN1::encodeDER($params, Maps\PBEParameter::MAP);
+            }
+            $crypto->setPassword($password, $kdf, $hash, $salt, $iterationCount);
+            $key = $crypto->encrypt($key);
+
+            $key = [
+                'encryptionAlgorithm' => [
+                    'algorithm' => $encryptionAlgorithm,
+                    'parameters' => new ASN1\Element($params)
+                ],
+                'encryptedData' => $key
+            ];
+
+            $key = ASN1::encodeDER($key, Maps\EncryptedPrivateKeyInfo::MAP);
+
+            return "-----BEGIN ENCRYPTED PRIVATE KEY-----\r\n" .
+                   chunk_split(Strings::base64_encode($key), 64) .
+                   "-----END ENCRYPTED PRIVATE KEY-----";
+        }
+
+        return "-----BEGIN PRIVATE KEY-----\r\n" .
+               chunk_split(Strings::base64_encode($key), 64) .
+               "-----END PRIVATE KEY-----";
+    }
+
+    /**
+     * Wrap a public key appropriately
+     *
+     * @param string $key
+     * @param mixed $params
+     * @param string $oid
+     * @return string
+     */
+    protected static function wrapPublicKey($key, $params, $oid = null)
+    {
+        self::initialize_static_variables();
+
+        $key = [
+            'publicKeyAlgorithm' => [
+                'algorithm' => is_string(static::OID_NAME) ? static::OID_NAME : $oid
+            ],
+            'publicKey' => "\0" . $key
+        ];
+
+        if ($oid != 'id-Ed25519' && $oid != 'id-Ed448') {
+            $key['publicKeyAlgorithm']['parameters'] = $params;
+        }
+
+        $key = ASN1::encodeDER($key, Maps\PublicKeyInfo::MAP);
+
+        return "-----BEGIN PUBLIC KEY-----\r\n" .
+               chunk_split(Strings::base64_encode($key), 64) .
+               "-----END PUBLIC KEY-----";
+    }
+
+    /**
+     * Perform some preliminary parsing of the key
+     *
+     * @param string $key
+     * @return array
+     */
+    private static function preParse(&$key)
+    {
+        self::initialize_static_variables();
+
+        if (!Strings::is_stringable($key)) {
+            throw new \UnexpectedValueException('Key should be a string - not a ' . gettype($key));
+        }
+
+        if (self::$format != self::MODE_DER) {
+            $decoded = ASN1::extractBER($key);
+            if ($decoded !== false) {
+                $key = $decoded;
+            } elseif (self::$format == self::MODE_PEM) {
+                throw new \UnexpectedValueException('Expected base64-encoded PEM format but was unable to decode base64 text');
+            }
+        }
+
+        $decoded = ASN1::decodeBER($key);
+        if (!$decoded) {
+            throw new \RuntimeException('Unable to decode BER');
+        }
+
+        return $decoded;
+    }
+
+    /**
+     * Returns the encryption parameters used by the key
+     *
+     * @param string $key
+     * @return array
+     */
+    public static function extractEncryptionAlgorithm($key)
+    {
+        $decoded = self::preParse($key);
+
+        $r = ASN1::asn1map($decoded[0], ASN1\Maps\EncryptedPrivateKeyInfo::MAP);
+        if (!is_array($r)) {
+            throw new \RuntimeException('Unable to parse using EncryptedPrivateKeyInfo map');
+        }
+
+        if ($r['encryptionAlgorithm']['algorithm'] == 'id-PBES2') {
+            $decoded = ASN1::decodeBER($r['encryptionAlgorithm']['parameters']->element);
+            if (!$decoded) {
+                throw new \RuntimeException('Unable to decode BER');
+            }
+            $r['encryptionAlgorithm']['parameters'] = ASN1::asn1map($decoded[0], ASN1\Maps\PBES2params::MAP);
+
+            $kdf = &$r['encryptionAlgorithm']['parameters']['keyDerivationFunc'];
+            switch ($kdf['algorithm']) {
+                case 'id-PBKDF2':
+                    $decoded = ASN1::decodeBER($kdf['parameters']->element);
+                    if (!$decoded) {
+                        throw new \RuntimeException('Unable to decode BER');
+                    }
+                    $kdf['parameters'] = ASN1::asn1map($decoded[0], Maps\PBKDF2params::MAP);
+            }
+        }
+
+        return $r['encryptionAlgorithm'];
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Keys/PuTTY.php

+<?php
+
+/**
+ * PuTTY Formatted Key Handler
+ *
+ * See PuTTY's SSHPUBK.C and https://tartarus.org/~simon/putty-snapshots/htmldoc/AppendixC.html
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2016 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Keys;
+
+use phpseclib3\Common\Functions\Strings;
+use phpseclib3\Crypt\AES;
+use phpseclib3\Crypt\Hash;
+use phpseclib3\Crypt\Random;
+use phpseclib3\Exception\UnsupportedAlgorithmException;
+
+/**
+ * PuTTY Formatted Key Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class PuTTY
+{
+    /**
+     * Default comment
+     *
+     * @var string
+     */
+    private static $comment = 'phpseclib-generated-key';
+
+    /**
+     * Default version
+     *
+     * @var int
+     */
+    private static $version = 2;
+
+    /**
+     * Sets the default comment
+     *
+     * @param string $comment
+     */
+    public static function setComment($comment)
+    {
+        self::$comment = str_replace(["\r", "\n"], '', $comment);
+    }
+
+    /**
+     * Sets the default version
+     *
+     * @param int $version
+     */
+    public static function setVersion($version)
+    {
+        if ($version != 2 && $version != 3) {
+            throw new \RuntimeException('Only supported versions are 2 and 3');
+        }
+        self::$version = $version;
+    }
+
+    /**
+     * Generate a symmetric key for PuTTY v2 keys
+     *
+     * @param string $password
+     * @param int $length
+     * @return string
+     */
+    private static function generateV2Key($password, $length)
+    {
+        $symkey = '';
+        $sequence = 0;
+        while (strlen($symkey) < $length) {
+            $temp = pack('Na*', $sequence++, $password);
+            $symkey .= Strings::hex2bin(sha1($temp));
+        }
+        return substr($symkey, 0, $length);
+    }
+
+    /**
+     * Generate a symmetric key for PuTTY v3 keys
+     *
+     * @param string $password
+     * @param string $flavour
+     * @param int $memory
+     * @param int $passes
+     * @param string $salt
+     * @return array
+     */
+    private static function generateV3Key($password, $flavour, $memory, $passes, $salt)
+    {
+        if (!function_exists('sodium_crypto_pwhash')) {
+            throw new \RuntimeException('sodium_crypto_pwhash needs to exist for Argon2 password hasing');
+        }
+
+        switch ($flavour) {
+            case 'Argon2i':
+                $flavour = SODIUM_CRYPTO_PWHASH_ALG_ARGON2I13;
+                break;
+            case 'Argon2id':
+                $flavour = SODIUM_CRYPTO_PWHASH_ALG_ARGON2ID13;
+                break;
+            default:
+                throw new UnsupportedAlgorithmException('Only Argon2i and Argon2id are supported');
+        }
+
+        $length = 80; // keylen + ivlen + mac_keylen
+        $temp = sodium_crypto_pwhash($length, $password, $salt, $passes, $memory << 10, $flavour);
+
+        $symkey = substr($temp, 0, 32);
+        $symiv = substr($temp, 32, 16);
+        $hashkey = substr($temp, -32);
+
+        return compact('symkey', 'symiv', 'hashkey');
+    }
+
+    /**
+     * Break a public or private key down into its constituent components
+     *
+     * @param string $key
+     * @param string $password
+     * @return array
+     */
+    public static function load($key, $password)
+    {
+        if (!Strings::is_stringable($key)) {
+            throw new \UnexpectedValueException('Key should be a string - not a ' . gettype($key));
+        }
+
+        if (strpos($key, 'BEGIN SSH2 PUBLIC KEY') !== false) {
+            $lines = preg_split('#[\r\n]+#', $key);
+            switch (true) {
+                case $lines[0] != '---- BEGIN SSH2 PUBLIC KEY ----':
+                    throw new \UnexpectedValueException('Key doesn\'t start with ---- BEGIN SSH2 PUBLIC KEY ----');
+                case $lines[count($lines) - 1] != '---- END SSH2 PUBLIC KEY ----':
+                    throw new \UnexpectedValueException('Key doesn\'t end with ---- END SSH2 PUBLIC KEY ----');
+            }
+            $lines = array_splice($lines, 1, -1);
+            $lines = array_map(function ($line) {
+                return rtrim($line, "\r\n");
+            }, $lines);
+            $data = $current = '';
+            $values = [];
+            $in_value = false;
+            foreach ($lines as $line) {
+                switch (true) {
+                    case preg_match('#^(.*?): (.*)#', $line, $match):
+                        $in_value = $line[strlen($line) - 1] == '\\';
+                        $current = strtolower($match[1]);
+                        $values[$current] = $in_value ? substr($match[2], 0, -1) : $match[2];
+                        break;
+                    case $in_value:
+                        $in_value = $line[strlen($line) - 1] == '\\';
+                        $values[$current] .= $in_value ? substr($line, 0, -1) : $line;
+                        break;
+                    default:
+                        $data .= $line;
+                }
+            }
+
+            $components = call_user_func([static::PUBLIC_HANDLER, 'load'], $data);
+            if ($components === false) {
+                throw new \UnexpectedValueException('Unable to decode public key');
+            }
+            $components += $values;
+            $components['comment'] = str_replace(['\\\\', '\"'], ['\\', '"'], $values['comment']);
+
+            return $components;
+        }
+
+        $components = [];
+
+        $key = preg_split('#\r\n|\r|\n#', trim($key));
+        if (Strings::shift($key[0], strlen('PuTTY-User-Key-File-')) != 'PuTTY-User-Key-File-') {
+            return false;
+        }
+        $version = (int) Strings::shift($key[0], 3); // should be either "2: " or "3: 0" prior to int casting
+        if ($version != 2 && $version != 3) {
+            throw new \RuntimeException('Only v2 and v3 PuTTY private keys are supported');
+        }
+        $components['type'] = $type = rtrim($key[0]);
+        if (!in_array($type, static::$types)) {
+            $error = count(static::$types) == 1 ?
+                'Only ' . static::$types[0] . ' keys are supported. ' :
+                '';
+            throw new UnsupportedAlgorithmException($error . 'This is an unsupported ' . $type . ' key');
+        }
+        $encryption = trim(preg_replace('#Encryption: (.+)#', '$1', $key[1]));
+        $components['comment'] = trim(preg_replace('#Comment: (.+)#', '$1', $key[2]));
+
+        $publicLength = trim(preg_replace('#Public-Lines: (\d+)#', '$1', $key[3]));
+        $public = Strings::base64_decode(implode('', array_map('trim', array_slice($key, 4, $publicLength))));
+
+        $source = Strings::packSSH2('ssss', $type, $encryption, $components['comment'], $public);
+
+        extract(unpack('Nlength', Strings::shift($public, 4)));
+        $newtype = Strings::shift($public, $length);
+        if ($newtype != $type) {
+            throw new \RuntimeException('The binary type does not match the human readable type field');
+        }
+
+        $components['public'] = $public;
+
+        switch ($version) {
+            case 3:
+                $hashkey = '';
+                break;
+            case 2:
+                $hashkey = 'putty-private-key-file-mac-key';
+        }
+
+        $offset = $publicLength + 4;
+        switch ($encryption) {
+            case 'aes256-cbc':
+                $crypto = new AES('cbc');
+                switch ($version) {
+                    case 3:
+                        $flavour = trim(preg_replace('#Key-Derivation: (.*)#', '$1', $key[$offset++]));
+                        $memory = trim(preg_replace('#Argon2-Memory: (\d+)#', '$1', $key[$offset++]));
+                        $passes = trim(preg_replace('#Argon2-Passes: (\d+)#', '$1', $key[$offset++]));
+                        $parallelism = trim(preg_replace('#Argon2-Parallelism: (\d+)#', '$1', $key[$offset++]));
+                        $salt = Strings::hex2bin(trim(preg_replace('#Argon2-Salt: ([0-9a-f]+)#', '$1', $key[$offset++])));
+
+                        extract(self::generateV3Key($password, $flavour, $memory, $passes, $salt));
+
+                        break;
+                    case 2:
+                        $symkey = self::generateV2Key($password, 32);
+                        $symiv = str_repeat("\0", $crypto->getBlockLength() >> 3);
+                        $hashkey .= $password;
+                }
+        }
+
+        switch ($version) {
+            case 3:
+                $hash = new Hash('sha256');
+                $hash->setKey($hashkey);
+                break;
+            case 2:
+                $hash = new Hash('sha1');
+                $hash->setKey(sha1($hashkey, true));
+        }
+
+        $privateLength = trim(preg_replace('#Private-Lines: (\d+)#', '$1', $key[$offset++]));
+        $private = Strings::base64_decode(implode('', array_map('trim', array_slice($key, $offset, $privateLength))));
+
+        if ($encryption != 'none') {
+            $crypto->setKey($symkey);
+            $crypto->setIV($symiv);
+            $crypto->disablePadding();
+            $private = $crypto->decrypt($private);
+        }
+
+        $source .= Strings::packSSH2('s', $private);
+
+        $hmac = trim(preg_replace('#Private-MAC: (.+)#', '$1', $key[$offset + $privateLength]));
+        $hmac = Strings::hex2bin($hmac);
+
+        if (!hash_equals($hash->hash($source), $hmac)) {
+            throw new \UnexpectedValueException('MAC validation error');
+        }
+
+        $components['private'] = $private;
+
+        return $components;
+    }
+
+    /**
+     * Wrap a private key appropriately
+     *
+     * @param string $public
+     * @param string $private
+     * @param string $type
+     * @param string $password
+     * @param array $options optional
+     * @return string
+     */
+    protected static function wrapPrivateKey($public, $private, $type, $password, array $options = [])
+    {
+        $encryption = (!empty($password) || is_string($password)) ? 'aes256-cbc' : 'none';
+        $comment = isset($options['comment']) ? $options['comment'] : self::$comment;
+        $version = isset($options['version']) ? $options['version'] : self::$version;
+
+        $key = "PuTTY-User-Key-File-$version: $type\r\n";
+        $key .= "Encryption: $encryption\r\n";
+        $key .= "Comment: $comment\r\n";
+
+        $public = Strings::packSSH2('s', $type) . $public;
+
+        $source = Strings::packSSH2('ssss', $type, $encryption, $comment, $public);
+
+        $public = Strings::base64_encode($public);
+        $key .= "Public-Lines: " . ((strlen($public) + 63) >> 6) . "\r\n";
+        $key .= chunk_split($public, 64);
+
+        if (empty($password) && !is_string($password)) {
+            $source .= Strings::packSSH2('s', $private);
+            switch ($version) {
+                case 3:
+                    $hash = new Hash('sha256');
+                    $hash->setKey('');
+                    break;
+                case 2:
+                    $hash = new Hash('sha1');
+                    $hash->setKey(sha1('putty-private-key-file-mac-key', true));
+            }
+        } else {
+            $private .= Random::string(16 - (strlen($private) & 15));
+            $source .= Strings::packSSH2('s', $private);
+            $crypto = new AES('cbc');
+
+            switch ($version) {
+                case 3:
+                    $salt = Random::string(16);
+                    $key .= "Key-Derivation: Argon2id\r\n";
+                    $key .= "Argon2-Memory: 8192\r\n";
+                    $key .= "Argon2-Passes: 13\r\n";
+                    $key .= "Argon2-Parallelism: 1\r\n";
+                    $key .= "Argon2-Salt: " . Strings::bin2hex($salt) . "\r\n";
+                    extract(self::generateV3Key($password, 'Argon2id', 8192, 13, $salt));
+
+                    $hash = new Hash('sha256');
+                    $hash->setKey($hashkey);
+
+                    break;
+                case 2:
+                    $symkey = self::generateV2Key($password, 32);
+                    $symiv = str_repeat("\0", $crypto->getBlockLength() >> 3);
+                    $hashkey = 'putty-private-key-file-mac-key' . $password;
+
+                    $hash = new Hash('sha1');
+                    $hash->setKey(sha1($hashkey, true));
+            }
+
+            $crypto->setKey($symkey);
+            $crypto->setIV($symiv);
+            $crypto->disablePadding();
+            $private = $crypto->encrypt($private);
+            $mac = $hash->hash($source);
+        }
+
+        $private = Strings::base64_encode($private);
+        $key .= 'Private-Lines: ' . ((strlen($private) + 63) >> 6) . "\r\n";
+        $key .= chunk_split($private, 64);
+        $key .= 'Private-MAC: ' . Strings::bin2hex($hash->hash($source)) . "\r\n";
+
+        return $key;
+    }
+
+    /**
+     * Wrap a public key appropriately
+     *
+     * This is basically the format described in RFC 4716 (https://tools.ietf.org/html/rfc4716)
+     *
+     * @param string $key
+     * @param string $type
+     * @return string
+     */
+    protected static function wrapPublicKey($key, $type)
+    {
+        $key = pack('Na*a*', strlen($type), $type, $key);
+        $key = "---- BEGIN SSH2 PUBLIC KEY ----\r\n" .
+               'Comment: "' . str_replace(['\\', '"'], ['\\\\', '\"'], self::$comment) . "\"\r\n" .
+               chunk_split(Strings::base64_encode($key), 64) .
+               '---- END SSH2 PUBLIC KEY ----';
+        return $key;
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/Formats/Signature/Raw.php

+<?php
+
+/**
+ * Raw Signature Handler
+ *
+ * PHP version 5
+ *
+ * Handles signatures as arrays
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2016 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common\Formats\Signature;
+
+use phpseclib3\Math\BigInteger;
+
+/**
+ * Raw Signature Handler
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class Raw
+{
+    /**
+     * Loads a signature
+     *
+     * @param array $sig
+     * @return array|bool
+     */
+    public static function load($sig)
+    {
+        switch (true) {
+            case !is_array($sig):
+            case !isset($sig['r']) || !isset($sig['s']):
+            case !$sig['r'] instanceof BigInteger:
+            case !$sig['s'] instanceof BigInteger:
+                return false;
+        }
+
+        return [
+            'r' => $sig['r'],
+            's' => $sig['s']
+        ];
+    }
+
+    /**
+     * Returns a signature in the appropriate format
+     *
+     * @param \phpseclib3\Math\BigInteger $r
+     * @param \phpseclib3\Math\BigInteger $s
+     * @return string
+     */
+    public static function save(BigInteger $r, BigInteger $s)
+    {
+        return compact('r', 's');
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/PrivateKey.php

+<?php
+
+/**
+ * PrivateKey interface
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2009 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common;
+
+/**
+ * PrivateKey interface
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+interface PrivateKey
+{
+    public function sign($message);
+    //public function decrypt($ciphertext);
+    public function getPublicKey();
+    public function toString($type, array $options = []);
+
+    /**
+     * @param string|false $password
+     * @return mixed
+     */
+    public function withPassword($password = false);
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/PublicKey.php

+<?php
+
+/**
+ * PublicKey interface
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @copyright 2009 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common;
+
+/**
+ * PublicKey interface
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+interface PublicKey
+{
+    public function verify($message, $signature);
+    //public function encrypt($plaintext);
+    public function toString($type, array $options = []);
+    public function getFingerprint($algorithm);
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/StreamCipher.php

+<?php
+
+/**
+ * Base Class for all stream ciphers
+ *
+ * PHP version 5
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @author    Hans-Juergen Petrich <petrich@tronic-media.com>
+ * @copyright 2007 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common;
+
+/**
+ * Base Class for all stream cipher classes
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ */
+abstract class StreamCipher extends SymmetricKey
+{
+    /**
+     * Block Length of the cipher
+     *
+     * Stream ciphers do not have a block size
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::block_size
+     * @var int
+     */
+    protected $block_size = 0;
+
+    /**
+     * Default Constructor.
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     * @return \phpseclib3\Crypt\Common\StreamCipher
+     */
+    public function __construct()
+    {
+        parent::__construct('stream');
+    }
+
+    /**
+     * Stream ciphers not use an IV
+     *
+     * @return bool
+     */
+    public function usesIV()
+    {
+        return false;
+    }
+}

examples/rabbitmq/vendor/phpseclib/phpseclib/phpseclib/Crypt/Common/SymmetricKey.php

+<?php
+
+/**
+ * Base Class for all \phpseclib3\Crypt\* cipher classes
+ *
+ * PHP version 5
+ *
+ * Internally for phpseclib developers:
+ *  If you plan to add a new cipher class, please note following rules:
+ *
+ *  - The new \phpseclib3\Crypt\* cipher class should extend \phpseclib3\Crypt\Common\SymmetricKey
+ *
+ *  - Following methods are then required to be overridden/overloaded:
+ *
+ *    - encryptBlock()
+ *
+ *    - decryptBlock()
+ *
+ *    - setupKey()
+ *
+ *  - All other methods are optional to be overridden/overloaded
+ *
+ *  - Look at the source code of the current ciphers how they extend \phpseclib3\Crypt\Common\SymmetricKey
+ *    and take one of them as a start up for the new cipher class.
+ *
+ *  - Please read all the other comments/notes/hints here also for each class var/method
+ *
+ * @author    Jim Wigginton <terrafrost@php.net>
+ * @author    Hans-Juergen Petrich <petrich@tronic-media.com>
+ * @copyright 2007 Jim Wigginton
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @link      http://phpseclib.sourceforge.net
+ */
+
+namespace phpseclib3\Crypt\Common;
+
+use phpseclib3\Common\Functions\Strings;
+use phpseclib3\Crypt\Blowfish;
+use phpseclib3\Crypt\Hash;
+use phpseclib3\Exception\BadDecryptionException;
+use phpseclib3\Exception\BadModeException;
+use phpseclib3\Exception\InconsistentSetupException;
+use phpseclib3\Exception\InsufficientSetupException;
+use phpseclib3\Exception\UnsupportedAlgorithmException;
+use phpseclib3\Math\BigInteger;
+use phpseclib3\Math\BinaryField;
+use phpseclib3\Math\PrimeField;
+
+/**
+ * Base Class for all \phpseclib3\Crypt\* cipher classes
+ *
+ * @author  Jim Wigginton <terrafrost@php.net>
+ * @author  Hans-Juergen Petrich <petrich@tronic-media.com>
+ */
+abstract class SymmetricKey
+{
+    /**
+     * Encrypt / decrypt using the Counter mode.
+     *
+     * Set to -1 since that's what Crypt/Random.php uses to index the CTR mode.
+     *
+     * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Counter_.28CTR.29
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_CTR = -1;
+    /**
+     * Encrypt / decrypt using the Electronic Code Book mode.
+     *
+     * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Electronic_codebook_.28ECB.29
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_ECB = 1;
+    /**
+     * Encrypt / decrypt using the Code Book Chaining mode.
+     *
+     * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher-block_chaining_.28CBC.29
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_CBC = 2;
+    /**
+     * Encrypt / decrypt using the Cipher Feedback mode.
+     *
+     * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher_feedback_.28CFB.29
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_CFB = 3;
+    /**
+     * Encrypt / decrypt using the Cipher Feedback mode (8bit)
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_CFB8 = 7;
+    /**
+     * Encrypt / decrypt using the Output Feedback mode (8bit)
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_OFB8 = 8;
+    /**
+     * Encrypt / decrypt using the Output Feedback mode.
+     *
+     * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_OFB = 4;
+    /**
+     * Encrypt / decrypt using Galois/Counter mode.
+     *
+     * @link https://en.wikipedia.org/wiki/Galois/Counter_Mode
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_GCM = 5;
+    /**
+     * Encrypt / decrypt using streaming mode.
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt()
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt()
+     */
+    const MODE_STREAM = 6;
+
+    /**
+     * Mode Map
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const MODE_MAP = [
+        'ctr'    => self::MODE_CTR,
+        'ecb'    => self::MODE_ECB,
+        'cbc'    => self::MODE_CBC,
+        'cfb'    => self::MODE_CFB,
+        'cfb8'   => self::MODE_CFB8,
+        'ofb'    => self::MODE_OFB,
+        'ofb8'   => self::MODE_OFB8,
+        'gcm'    => self::MODE_GCM,
+        'stream' => self::MODE_STREAM
+    ];
+
+    /**
+     * Base value for the internal implementation $engine switch
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const ENGINE_INTERNAL = 1;
+    /**
+     * Base value for the eval() implementation $engine switch
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const ENGINE_EVAL = 2;
+    /**
+     * Base value for the mcrypt implementation $engine switch
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const ENGINE_MCRYPT = 3;
+    /**
+     * Base value for the openssl implementation $engine switch
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const ENGINE_OPENSSL = 4;
+    /**
+     * Base value for the libsodium implementation $engine switch
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const ENGINE_LIBSODIUM = 5;
+    /**
+     * Base value for the openssl / gcm implementation $engine switch
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::__construct()
+     */
+    const ENGINE_OPENSSL_GCM = 6;
+
+    /**
+     * Engine Reverse Map
+     *
+     * @see \phpseclib3\Crypt\Common\SymmetricKey::getEngine()
+     */
+    const ENGINE_MAP = [
+        self::ENGINE_INTERNAL    => 'PHP',
+        self::ENGINE_EVAL        => 'Eval',
+        self::ENGINE_MCRYPT      => 'mcrypt',
+        self::ENGINE_OPENSSL     => 'OpenSSL',
+        self::ENGINE_LIBSODIUM   => 'libsodium',
+        self::ENGINE_OPENSSL_GCM => 'OpenSSL (GCM)'
+    ];
+
+    /**
+     * The Encryption Mode
+     *
+     * @see self::__construct()
+     * @var int
+     */
+    protected $mode;
+
+    /**
+     * The Block Length of the block cipher
+     *
+     * @var int
+     */
+    protected $block_size = 16;
+
+    /**
+     * The Key
+     *
+     * @see self::setKey()
+     * @var string
+     */
+    protected $key = false;
+
+    /**
+     * HMAC Key
+     *
+     * @see self::setupGCM()
+     * @var ?string
+     */
+    protected $hKey = false;
+
+    /**
+     * The Initialization Vector
+     *
+     * @see self::setIV()
+     * @var string
+     */
+    protected $iv = false;
+
+    /**
+     * A "sliding" Initialization Vector
+     *
+     * @see self::enableContinuousBuffer()
+     * @see self::clearBuffers()
+     * @var string
+     */
+    protected $encryptIV;
+
+    /**
+     * A "sliding" Initialization Vector
+     *
+     * @see self::enableContinuousBuffer()
+     * @see self::clearBuffers()
+     * @var string
+     */
+    protected $decryptIV;
+
+    /**
+     * Continuous Buffer status
+     *
+     * @see self::enableContinuousBuffer()
+     * @var bool
+     */
+    protected $continuousBuffer = false;
+
+    /**
+     * Encryption buffer for CTR, OFB and CFB modes
+     *
+     * @see self::encrypt()
+     * @see self::clearBuffers()
+     * @var array
+     */
+    protected $enbuffer;
+
+    /**
+     * Decryption buffer for CTR, OFB and CFB modes
+     *
+     * @see self::decrypt()
+     * @see self::clearBuffers()
+     * @var array
+     */
+    protected $debuffer;
+
+    /**
+     * mcrypt resource for encryption
+     *
+     * The mcrypt resource can be recreated every time something needs to be created or it can be created just once.
+     * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode.
+     *
+     * @see self::encrypt()
+     * @var resource
+     */
+    private $enmcrypt;
+
+    /**
+     * mcrypt resource for decryption
+     *
+     * The mcrypt resource can be recreated every time something needs to be created or it can be created just once.
+     * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode.
+     *
+     * @see self::decrypt()
+     * @var resource
+     */
+    private $demcrypt;
+
+    /**
+     * Does the enmcrypt resource need to be (re)initialized?
+     *
+     * @see \phpseclib3\Crypt\Twofish::setKey()
+     * @see \phpseclib3\Crypt\Twofish::setIV()
+     * @var bool
+     */
+    private $enchanged = true;
+
+    /**
+     * Does the demcrypt resource need to be (re)initialized?
+     *
+     * @see \phpseclib3\Crypt\Twofish::setKey()
+     * @see \phpseclib3\Crypt\Twofish::setIV()
+     * @var bool
+     */
+    private $dechanged = true;
+
+    /**
+     * mcrypt resource for CFB mode
+     *
+     * mcrypt's CFB mode, in (and only in) buffered context,
+     * is broken, so phpseclib implements the CFB mode by it self,
+     * even when the mcrypt php extension is available.
+     *
+     * In order to do the CFB-mode work (fast) phpseclib
+     * use a separate ECB-mode mcrypt resource.
+     *
+     * @link http://phpseclib.sourceforge.net/cfb-demo.phps
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @see self::setupMcrypt()
+     * @var resource
+     */
+    private $ecb;
+
+    /**
+     * Optimizing value while CFB-encrypting
+     *
+     * Only relevant if $continuousBuffer enabled
+     * and $engine == self::ENGINE_MCRYPT
+     *
+     * It's faster to re-init $enmcrypt if
+     * $buffer bytes > $cfb_init_len than
+     * using the $ecb resource furthermore.
+     *
+     * This value depends of the chosen cipher
+     * and the time it would be needed for it's
+     * initialization [by mcrypt_generic_init()]
+     * which, typically, depends on the complexity
+     * on its internaly Key-expanding algorithm.
+     *
+     * @see self::encrypt()
+     * @var int
+     */
+    protected $cfb_init_len = 600;
+
+    /**
+     * Does internal cipher state need to be (re)initialized?
+     *
+     * @see self::setKey()
+     * @see self::setIV()
+     * @see self::disableContinuousBuffer()
+     * @var bool
+     */
+    protected $changed = true;
+
+    /**
+     * Does Eval engie need to be (re)initialized?
+     *
+     * @see self::setup()
+     * @var bool
+     */
+    protected $nonIVChanged = true;
+
+    /**
+     * Padding status
+     *
+     * @see self::enablePadding()
+     * @var bool
+     */
+    private $padding = true;
+
+    /**
+     * Is the mode one that is paddable?
+     *
+     * @see self::__construct()
+     * @var bool
+     */
+    private $paddable = false;
+
+    /**
+     * Holds which crypt engine internaly should be use,
+     * which will be determined automatically on __construct()
+     *
+     * Currently available $engines are:
+     * - self::ENGINE_LIBSODIUM   (very fast, php-extension: libsodium, extension_loaded('libsodium') required)
+     * - self::ENGINE_OPENSSL_GCM (very fast, php-extension: openssl, extension_loaded('openssl') required)
+     * - self::ENGINE_OPENSSL     (very fast, php-extension: openssl, extension_loaded('openssl') required)
+     * - self::ENGINE_MCRYPT      (fast, php-extension: mcrypt, extension_loaded('mcrypt') required)
+     * - self::ENGINE_EVAL        (medium, pure php-engine, no php-extension required)
+     * - self::ENGINE_INTERNAL    (slower, pure php-engine, no php-extension required)
+     *
+     * @see self::setEngine()
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @var int
+     */
+    protected $engine;
+
+    /**
+     * Holds the preferred crypt engine
+     *
+     * @see self::setEngine()
+     * @see self::setPreferredEngine()
+     * @var int
+     */
+    private $preferredEngine;
+
+    /**
+     * The mcrypt specific name of the cipher
+     *
+     * Only used if $engine == self::ENGINE_MCRYPT
+     *
+     * @link http://www.php.net/mcrypt_module_open
+     * @link http://www.php.net/mcrypt_list_algorithms
+     * @see self::setupMcrypt()
+     * @var string
+     */
+    protected $cipher_name_mcrypt;
+
+    /**
+     * The openssl specific name of the cipher
+     *
+     * Only used if $engine == self::ENGINE_OPENSSL
+     *
+     * @link http://www.php.net/openssl-get-cipher-methods
+     * @var string
+     */
+    protected $cipher_name_openssl;
+
+    /**
+     * The openssl specific name of the cipher in ECB mode
+     *
+     * If OpenSSL does not support the mode we're trying to use (CTR)
+     * it can still be emulated with ECB mode.
+     *
+     * @link http://www.php.net/openssl-get-cipher-methods
+     * @var string
+     */
+    protected $cipher_name_openssl_ecb;
+
+    /**
+     * The default salt used by setPassword()
+     *
+     * @see self::setPassword()
+     * @var string
+     */
+    private $password_default_salt = 'phpseclib/salt';
+
+    /**
+     * The name of the performance-optimized callback function
+     *
+     * Used by encrypt() / decrypt()
+     * only if $engine == self::ENGINE_INTERNAL
+     *
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @see self::setupInlineCrypt()
+     * @var Callback
+     */
+    protected $inline_crypt;
+
+    /**
+     * If OpenSSL can be used in ECB but not in CTR we can emulate CTR
+     *
+     * @see self::openssl_ctr_process()
+     * @var bool
+     */
+    private $openssl_emulate_ctr = false;
+
+    /**
+     * Don't truncate / null pad key
+     *
+     * @see self::clearBuffers()
+     * @var bool
+     */
+    private $skip_key_adjustment = false;
+
+    /**
+     * Has the key length explicitly been set or should it be derived from the key, itself?
+     *
+     * @see self::setKeyLength()
+     * @var bool
+     */
+    protected $explicit_key_length = false;
+
+    /**
+     * Hash subkey for GHASH
+     *
+     * @see self::setupGCM()
+     * @see self::ghash()
+     * @var BinaryField\Integer
+     */
+    private $h;
+
+    /**
+     * Additional authenticated data
+     *
+     * @var string
+     */
+    protected $aad = '';
+
+    /**
+     * Authentication Tag produced after a round of encryption
+     *
+     * @var string
+     */
+    protected $newtag = false;
+
+    /**
+     * Authentication Tag to be verified during decryption
+     *
+     * @var string
+     */
+    protected $oldtag = false;
+
+    /**
+     * GCM Binary Field
+     *
+     * @see self::__construct()
+     * @see self::ghash()
+     * @var BinaryField
+     */
+    private static $gcmField;
+
+    /**
+     * Poly1305 Prime Field
+     *
+     * @see self::enablePoly1305()
+     * @see self::poly1305()
+     * @var PrimeField
+     */
+    private static $poly1305Field;
+
+    /**
+     * Flag for using regular vs "safe" intval
+     *
+     * @see self::initialize_static_variables()
+     * @var boolean
+     */
+    protected static $use_reg_intval;
+
+    /**
+     * Poly1305 Key
+     *
+     * @see self::setPoly1305Key()
+     * @see self::poly1305()
+     * @var string
+     */
+    protected $poly1305Key;
+
+    /**
+     * Poly1305 Flag
+     *
+     * @see self::setPoly1305Key()
+     * @see self::enablePoly1305()
+     * @var boolean
+     */
+    protected $usePoly1305 = false;
+
+    /**
+     * The Original Initialization Vector
+     *
+     * GCM uses the nonce to build the IV but we want to be able to distinguish between nonce-derived
+     * IV's and user-set IV's
+     *
+     * @see self::setIV()
+     * @var string
+     */
+    private $origIV = false;
+
+    /**
+     * Nonce
+     *
+     * Only used with GCM. We could re-use setIV() but nonce's can be of a different length and
+     * toggling between GCM and other modes could be more complicated if we re-used setIV()
+     *
+     * @see self::setNonce()
+     * @var string
+     */
+    protected $nonce = false;
+
+    /**
+     * Default Constructor.
+     *
+     * $mode could be:
+     *
+     * - ecb
+     *
+     * - cbc
+     *
+     * - ctr
+     *
+     * - cfb
+     *
+     * - cfb8
+     *
+     * - ofb
+     *
+     * - ofb8
+     *
+     * - gcm
+     *
+     * @param string $mode
+     * @throws BadModeException if an invalid / unsupported mode is provided
+     */
+    public function __construct($mode)
+    {
+        $mode = strtolower($mode);
+        // necessary because of 5.6 compatibility; we can't do isset(self::MODE_MAP[$mode]) in 5.6
+        $map = self::MODE_MAP;
+        if (!isset($map[$mode])) {
+            throw new BadModeException('No valid mode has been specified');
+        }
+
+        $mode = self::MODE_MAP[$mode];
+
+        // $mode dependent settings
+        switch ($mode) {
+            case self::MODE_ECB:
+            case self::MODE_CBC:
+                $this->paddable = true;
+                break;
+            case self::MODE_CTR:
+            case self::MODE_CFB:
+            case self::MODE_CFB8:
+            case self::MODE_OFB:
+            case self::MODE_OFB8:
+            case self::MODE_STREAM:
+                $this->paddable = false;
+                break;
+            case self::MODE_GCM:
+                if ($this->block_size != 16) {
+                    throw new BadModeException('GCM is only valid for block ciphers with a block size of 128 bits');
+                }
+                if (!isset(self::$gcmField)) {
+                    self::$gcmField = new BinaryField(128, 7, 2, 1, 0);
+                }
+                $this->paddable = false;
+                break;
+            default:
+                throw new BadModeException('No valid mode has been specified');
+        }
+
+        $this->mode = $mode;
+
+        static::initialize_static_variables();
+    }
+
+    /**
+     * Initialize static variables
+     */
+    protected static function initialize_static_variables()
+    {
+        if (!isset(self::$use_reg_intval)) {
+            switch (true) {
+                // PHP_OS & "\xDF\xDF\xDF" == strtoupper(substr(PHP_OS, 0, 3)), but a lot faster
+                case (PHP_OS & "\xDF\xDF\xDF") === 'WIN':
+                case (php_uname('m') & "\xDF\xDF\xDF") != 'ARM':
+                case defined('PHP_INT_SIZE') && PHP_INT_SIZE == 8:
+                    self::$use_reg_intval = true;
+                    break;
+                case (php_uname('m') & "\xDF\xDF\xDF") == 'ARM':
+                    switch (true) {
+                        /* PHP 7.0.0 introduced a bug that affected 32-bit ARM processors:
+
+                           https://github.com/php/php-src/commit/716da71446ebbd40fa6cf2cea8a4b70f504cc3cd
+
+                           altho the changelogs make no mention of it, this bug was fixed with this commit:
+
+                           https://github.com/php/php-src/commit/c1729272b17a1fe893d1a54e423d3b71470f3ee8
+
+                           affected versions of PHP are: 7.0.x, 7.1.0 - 7.1.23 and 7.2.0 - 7.2.11 */
+                        case PHP_VERSION_ID >= 70000 && PHP_VERSION_ID <= 70123:
+                        case PHP_VERSION_ID >= 70200 && PHP_VERSION_ID <= 70211:
+                            self::$use_reg_intval = false;
+                            break;
+                        default:
+                            self::$use_reg_intval = true;
+                    }
+            }
+        }
+    }
+
+    /**
+     * Sets the initialization vector.
+     *
+     * setIV() is not required when ecb or gcm modes are being used.
+     *
+     * {@internal Can be overwritten by a sub class, but does not have to be}
+     *
+     * @param string $iv
+     * @throws \LengthException if the IV length isn't equal to the block size
+     * @throws \BadMethodCallException if an IV is provided when one shouldn't be
+     */
+    public function setIV($iv)
+    {
+        if ($this->mode == self::MODE_ECB) {
+            throw new \BadMethodCallException('This mode does not require an IV.');
+        }
+
+        if ($this->mode == self::MODE_GCM) {
+            throw new \BadMethodCallException('Use setNonce instead');
+        }
+
+        if (!$this->usesIV()) {
+            throw new \BadMethodCallException('This algorithm does not use an IV.');
+        }
+
+        if (strlen($iv) != $this->block_size) {
+            throw new \LengthException('Received initialization vector of size ' . strlen($iv) . ', but size ' . $this->block_size . ' is required');
+        }
+
+        $this->iv = $this->origIV = $iv;
+        $this->changed = true;
+    }
+
+    /**
+     * Enables Poly1305 mode.
+     *
+     * Once enabled Poly1305 cannot be disabled.
+     *
+     * @throws \BadMethodCallException if Poly1305 is enabled whilst in GCM mode
+     */
+    public function enablePoly1305()
+    {
+        if ($this->mode == self::MODE_GCM) {
+            throw new \BadMethodCallException('Poly1305 cannot be used in GCM mode');
+        }
+
+        $this->usePoly1305 = true;
+    }
+
+    /**
+     * Enables Poly1305 mode.
+     *
+     * Once enabled Poly1305 cannot be disabled. If $key is not passed then an attempt to call createPoly1305Key
+     * will be made.
+     *
+     * @param string $key optional
+     * @throws \LengthException if the key isn't long enough
+     * @throws \BadMethodCallException if Poly1305 is enabled whilst in GCM mode
+     */
+    public function setPoly1305Key($key = null)
+    {
+        if ($this->mode == self::MODE_GCM) {
+            throw new \BadMethodCallException('Poly1305 cannot be used in GCM mode');
+        }
+
+        if (!is_string($key) || strlen($key) != 32) {
+            throw new \LengthException('The Poly1305 key must be 32 bytes long (256 bits)');
+        }
+
+        if (!isset(self::$poly1305Field)) {
+            // 2^130-5
+            self::$poly1305Field = new PrimeField(new BigInteger('3fffffffffffffffffffffffffffffffb', 16));
+        }
+
+        $this->poly1305Key = $key;
+        $this->usePoly1305 = true;
+    }
+
+    /**
+     * Sets the nonce.
+     *
+     * setNonce() is only required when gcm is used
+     *
+     * @param string $nonce
+     * @throws \BadMethodCallException if an nonce is provided when one shouldn't be
+     */
+    public function setNonce($nonce)
+    {
+        if ($this->mode != self::MODE_GCM) {
+            throw new \BadMethodCallException('Nonces are only used in GCM mode.');
+        }
+
+        $this->nonce = $nonce;
+        $this->setEngine();
+    }
+
+    /**
+     * Sets additional authenticated data
+     *
+     * setAAD() is only used by gcm or in poly1305 mode
+     *
+     * @param string $aad
+     * @throws \BadMethodCallException if mode isn't GCM or if poly1305 isn't being utilized
+     */
+    public function setAAD($aad)
+    {
+        if ($this->mode != self::MODE_GCM && !$this->usePoly1305) {
+            throw new \BadMethodCallException('Additional authenticated data is only utilized in GCM mode or with Poly1305');
+        }
+
+        $this->aad = $aad;
+    }
+
+    /**
+     * Returns whether or not the algorithm uses an IV
+     *
+     * @return bool
+     */
+    public function usesIV()
+    {
+        return $this->mode != self::MODE_GCM && $this->mode != self::MODE_ECB;
+    }
+
+    /**
+     * Returns whether or not the algorithm uses a nonce
+     *
+     * @return bool
+     */
+    public function usesNonce()
+    {
+        return $this->mode == self::MODE_GCM;
+    }
+
+    /**
+     * Returns the current key length in bits
+     *
+     * @return int
+     */
+    public function getKeyLength()
+    {
+        return $this->key_length << 3;
+    }
+
+    /**
+     * Returns the current block length in bits
+     *
+     * @return int
+     */
+    public function getBlockLength()
+    {
+        return $this->block_size << 3;
+    }
+
+    /**
+     * Returns the current block length in bytes
+     *
+     * @return int
+     */
+    public function getBlockLengthInBytes()
+    {
+        return $this->block_size;
+    }
+
+    /**
+     * Sets the key length.
+     *
+     * Keys with explicitly set lengths need to be treated accordingly
+     *
+     * @param int $length
+     */
+    public function setKeyLength($length)
+    {
+        $this->explicit_key_length = $length >> 3;
+
+        if (is_string($this->key) && strlen($this->key) != $this->explicit_key_length) {
+            $this->key = false;
+            throw new InconsistentSetupException('Key has already been set and is not ' . $this->explicit_key_length . ' bytes long');
+        }
+    }
+
+    /**
+     * Sets the key.
+     *
+     * The min/max length(s) of the key depends on the cipher which is used.
+     * If the key not fits the length(s) of the cipher it will paded with null bytes
+     * up to the closest valid key length.  If the key is more than max length,
+     * we trim the excess bits.
+     *
+     * If the key is not explicitly set, it'll be assumed to be all null bytes.
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @param string $key
+     */
+    public function setKey($key)
+    {
+        if ($this->explicit_key_length !== false && strlen($key) != $this->explicit_key_length) {
+            throw new InconsistentSetupException('Key length has already been set to ' . $this->explicit_key_length . ' bytes and this key is ' . strlen($key) . ' bytes');
+        }
+
+        $this->key = $key;
+        $this->key_length = strlen($key);
+        $this->setEngine();
+    }
+
+    /**
+     * Sets the password.
+     *
+     * Depending on what $method is set to, setPassword()'s (optional) parameters are as follows:
+     *     {@link http://en.wikipedia.org/wiki/PBKDF2 pbkdf2} or pbkdf1:
+     *         $hash, $salt, $count, $dkLen
+     *
+     *         Where $hash (default = sha1) currently supports the following hashes: see: Crypt/Hash.php
+     *     {@link https://en.wikipedia.org/wiki/Bcrypt bcypt}:
+     *         $salt, $rounds, $keylen
+     *
+     *         This is a modified version of bcrypt used by OpenSSH.
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @see Crypt/Hash.php
+     * @param string $password
+     * @param string $method
+     * @param string[] ...$func_args
+     * @throws \LengthException if pbkdf1 is being used and the derived key length exceeds the hash length
+     * @throws \RuntimeException if bcrypt is being used and a salt isn't provided
+     * @return bool
+     */
+    public function setPassword($password, $method = 'pbkdf2', ...$func_args)
+    {
+        $key = '';
+
+        $method = strtolower($method);
+        switch ($method) {
+            case 'bcrypt':
+                if (!isset($func_args[2])) {
+                    throw new \RuntimeException('A salt must be provided for bcrypt to work');
+                }
+
+                $salt = $func_args[0];
+
+                $rounds = isset($func_args[1]) ? $func_args[1] : 16;
+                $keylen = isset($func_args[2]) ? $func_args[2] : $this->key_length;
+
+                $key = Blowfish::bcrypt_pbkdf($password, $salt, $keylen + $this->block_size, $rounds);
+
+                $this->setKey(substr($key, 0, $keylen));
+                $this->setIV(substr($key, $keylen));
+
+                return true;
+            case 'pkcs12': // from https://tools.ietf.org/html/rfc7292#appendix-B.2
+            case 'pbkdf1':
+            case 'pbkdf2':
+                // Hash function
+                $hash = isset($func_args[0]) ? strtolower($func_args[0]) : 'sha1';
+                $hashObj = new Hash();
+                $hashObj->setHash($hash);
+
+                // WPA and WPA2 use the SSID as the salt
+                $salt = isset($func_args[1]) ? $func_args[1] : $this->password_default_salt;
+
+                // RFC2898#section-4.2 uses 1,000 iterations by default
+                // WPA and WPA2 use 4,096.
+                $count = isset($func_args[2]) ? $func_args[2] : 1000;
+
+                // Keylength
+                if (isset($func_args[3])) {
+                    if ($func_args[3] <= 0) {
+                        throw new \LengthException('Derived key length cannot be longer 0 or less');
+                    }
+                    $dkLen = $func_args[3];
+                } else {
+                    $key_length = $this->explicit_key_length !== false ? $this->explicit_key_length : $this->key_length;
+                    $dkLen = $method == 'pbkdf1' ? 2 * $key_length : $key_length;
+                }
+
+                switch (true) {
+                    case $method == 'pkcs12':
+                        /*
+                         In this specification, however, all passwords are created from
+                         BMPStrings with a NULL terminator.  This means that each character in
+                         the original BMPString is encoded in 2 bytes in big-endian format
+                         (most-significant byte first).  There are no Unicode byte order
+                         marks.  The 2 bytes produced from the last character in the BMPString
+                         are followed by 2 additional bytes with the value 0x00.
+
+                         -- https://tools.ietf.org/html/rfc7292#appendix-B.1
+                         */
+                        $password = "\0" . chunk_split($password, 1, "\0") . "\0";
+
+                        /*
+                         This standard specifies 3 different values for the ID byte mentioned
+                         above:
+
+                         1.  If ID=1, then the pseudorandom bits being produced are to be used
+                             as key material for performing encryption or decryption.
+
+                         2.  If ID=2, then the pseudorandom bits being produced are to be used
+                             as an IV (Initial Value) for encryption or decryption.
+
+                         3.  If ID=3, then the pseudorandom bits being produced are to be used
+                             as an integrity key for MACing.
+                         */
+                        // Construct a string, D (the "diversifier"), by concatenating v/8
+                        // copies of ID.
+                        $blockLength = $hashObj->getBlockLengthInBytes();
+                        $d1 = str_repeat(chr(1), $blockLength);
+                        $d2 = str_repeat(chr(2), $blockLength);
+                        $s = '';
+                        if (strlen($salt)) {
+                            while (strlen($s) < $blockLength) {
+                                $s .= $salt;
+                            }
+                        }
+                        $s = substr($s, 0, $blockLength);
+
+                        $p = '';
+                        if (strlen($password)) {
+                            while (strlen($p) < $blockLength) {
+                                $p .= $password;
+                            }
+                        }
+                        $p = substr($p, 0, $blockLength);
+
+                        $i = $s . $p;
+
+                        $this->setKey(self::pkcs12helper($dkLen, $hashObj, $i, $d1, $count));
+                        if ($this->usesIV()) {
+                            $this->setIV(self::pkcs12helper($this->block_size, $hashObj, $i, $d2, $count));
+                        }
+
+                        return true;
+                    case $method == 'pbkdf1':
+                        if ($dkLen > $hashObj->getLengthInBytes()) {
+                            throw new \LengthException('Derived key length cannot be longer than the hash length');
+                        }
+                        $t = $password . $salt;
+                        for ($i = 0; $i < $count; ++$i) {
+                            $t = $hashObj->hash($t);
+                        }
+                        $key = substr($t, 0, $dkLen);
+
+                        $this->setKey(substr($key, 0, $dkLen >> 1));
+                        if ($this->usesIV()) {
+                            $this->setIV(substr($key, $dkLen >> 1));
+                        }
+
+                        return true;
+                    case !in_array($hash, hash_algos()):
+                        $i = 1;
+                        $hashObj->setKey($password);
+                        while (strlen($key) < $dkLen) {
+                            $f = $u = $hashObj->hash($salt . pack('N', $i++));
+                            for ($j = 2; $j <= $count; ++$j) {
+                                $u = $hashObj->hash($u);
+                                $f ^= $u;
+                            }
+                            $key .= $f;
+                        }
+                        $key = substr($key, 0, $dkLen);
+                        break;
+                    default:
+                        $key = hash_pbkdf2($hash, $password, $salt, $count, $dkLen, true);
+                }
+                break;
+            default:
+                throw new UnsupportedAlgorithmException($method . ' is not a supported password hashing method');
+        }
+
+        $this->setKey($key);
+
+        return true;
+    }
+
+    /**
+     * PKCS#12 KDF Helper Function
+     *
+     * As discussed here:
+     *
+     * {@link https://tools.ietf.org/html/rfc7292#appendix-B}
+     *
+     * @see self::setPassword()
+     * @param int $n
+     * @param \phpseclib3\Crypt\Hash $hashObj
+     * @param string $i
+     * @param string $d
+     * @param int $count
+     * @return string $a
+     */
+    private static function pkcs12helper($n, $hashObj, $i, $d, $count)
+    {
+        static $one;
+        if (!isset($one)) {
+            $one = new BigInteger(1);
+        }
+
+        $blockLength = $hashObj->getBlockLength() >> 3;
+
+        $c = ceil($n / $hashObj->getLengthInBytes());
+        $a = '';
+        for ($j = 1; $j <= $c; $j++) {
+            $ai = $d . $i;
+            for ($k = 0; $k < $count; $k++) {
+                $ai = $hashObj->hash($ai);
+            }
+            $b = '';
+            while (strlen($b) < $blockLength) {
+                $b .= $ai;
+            }
+            $b = substr($b, 0, $blockLength);
+            $b = new BigInteger($b, 256);
+            $newi = '';
+            for ($k = 0; $k < strlen($i); $k += $blockLength) {
+                $temp = substr($i, $k, $blockLength);
+                $temp = new BigInteger($temp, 256);
+                $temp->setPrecision($blockLength << 3);
+                $temp = $temp->add($b);
+                $temp = $temp->add($one);
+                $newi .= $temp->toBytes(false);
+            }
+            $i = $newi;
+            $a .= $ai;
+        }
+
+        return substr($a, 0, $n);
+    }
+
+    /**
+     * Encrypts a message.
+     *
+     * $plaintext will be padded with additional bytes such that it's length is a multiple of the block size. Other cipher
+     * implementations may or may not pad in the same manner.  Other common approaches to padding and the reasons why it's
+     * necessary are discussed in the following
+     * URL:
+     *
+     * {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html}
+     *
+     * An alternative to padding is to, separately, send the length of the file.  This is what SSH, in fact, does.
+     * strlen($plaintext) will still need to be a multiple of the block size, however, arbitrary values can be added to make it that
+     * length.
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @see self::decrypt()
+     * @param string $plaintext
+     * @return string $ciphertext
+     */
+    public function encrypt($plaintext)
+    {
+        if ($this->paddable) {
+            $plaintext = $this->pad($plaintext);
+        }
+
+        $this->setup();
+
+        if ($this->mode == self::MODE_GCM) {
+            $oldIV = $this->iv;
+            Strings::increment_str($this->iv);
+            $cipher = new static('ctr');
+            $cipher->setKey($this->key);
+            $cipher->setIV($this->iv);
+            $ciphertext = $cipher->encrypt($plaintext);
+
+            $s = $this->ghash(
+                self::nullPad128($this->aad) .
+                self::nullPad128($ciphertext) .
+                self::len64($this->aad) .
+                self::len64($ciphertext)
+            );
+            $cipher->encryptIV = $this->iv = $this->encryptIV = $this->decryptIV = $oldIV;
+            $this->newtag = $cipher->encrypt($s);
+            return $ciphertext;
+        }
+
+        if (isset($this->poly1305Key)) {
+            $cipher = clone $this;
+            unset($cipher->poly1305Key);
+            $this->usePoly1305 = false;
+            $ciphertext = $cipher->encrypt($plaintext);
+            $this->newtag = $this->poly1305($ciphertext);
+            return $ciphertext;
+        }
+
+        if ($this->engine === self::ENGINE_OPENSSL) {
+            switch ($this->mode) {
+                case self::MODE_STREAM:
+                    return openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+                case self::MODE_ECB:
+                    return openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+                case self::MODE_CBC:
+                    $result = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->encryptIV);
+                    if ($this->continuousBuffer) {
+                        $this->encryptIV = substr($result, -$this->block_size);
+                    }
+                    return $result;
+                case self::MODE_CTR:
+                    return $this->openssl_ctr_process($plaintext, $this->encryptIV, $this->enbuffer);
+                case self::MODE_CFB:
+                    // cfb loosely routines inspired by openssl's:
+                    // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1}
+                    $ciphertext = '';
+                    if ($this->continuousBuffer) {
+                        $iv = &$this->encryptIV;
+                        $pos = &$this->enbuffer['pos'];
+                    } else {
+                        $iv = $this->encryptIV;
+                        $pos = 0;
+                    }
+                    $len = strlen($plaintext);
+                    $i = 0;
+                    if ($pos) {
+                        $orig_pos = $pos;
+                        $max = $this->block_size - $pos;
+                        if ($len >= $max) {
+                            $i = $max;
+                            $len -= $max;
+                            $pos = 0;
+                        } else {
+                            $i = $len;
+                            $pos += $len;
+                            $len = 0;
+                        }
+                        // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+                        $ciphertext = substr($iv, $orig_pos) ^ $plaintext;
+                        $iv = substr_replace($iv, $ciphertext, $orig_pos, $i);
+                        $plaintext = substr($plaintext, $i);
+                    }
+
+                    $overflow = $len % $this->block_size;
+
+                    if ($overflow) {
+                        $ciphertext .= openssl_encrypt(substr($plaintext, 0, -$overflow) . str_repeat("\0", $this->block_size), $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv);
+                        $iv = Strings::pop($ciphertext, $this->block_size);
+
+                        $size = $len - $overflow;
+                        $block = $iv ^ substr($plaintext, -$overflow);
+                        $iv = substr_replace($iv, $block, 0, $overflow);
+                        $ciphertext .= $block;
+                        $pos = $overflow;
+                    } elseif ($len) {
+                        $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv);
+                        $iv = substr($ciphertext, -$this->block_size);
+                    }
+
+                    return $ciphertext;
+                case self::MODE_CFB8:
+                    $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->encryptIV);
+                    if ($this->continuousBuffer) {
+                        if (($len = strlen($ciphertext)) >= $this->block_size) {
+                            $this->encryptIV = substr($ciphertext, -$this->block_size);
+                        } else {
+                            $this->encryptIV = substr($this->encryptIV, $len - $this->block_size) . substr($ciphertext, -$len);
+                        }
+                    }
+                    return $ciphertext;
+                case self::MODE_OFB8:
+                    $ciphertext = '';
+                    $len = strlen($plaintext);
+                    $iv = $this->encryptIV;
+
+                    for ($i = 0; $i < $len; ++$i) {
+                        $xor = openssl_encrypt($iv, $this->cipher_name_openssl_ecb, $this->key, $this->openssl_options, $this->decryptIV);
+                        $ciphertext .= $plaintext[$i] ^ $xor;
+                        $iv = substr($iv, 1) . $xor[0];
+                    }
+
+                    if ($this->continuousBuffer) {
+                        $this->encryptIV = $iv;
+                    }
+                    break;
+                case self::MODE_OFB:
+                    return $this->openssl_ofb_process($plaintext, $this->encryptIV, $this->enbuffer);
+            }
+        }
+
+        if ($this->engine === self::ENGINE_MCRYPT) {
+            set_error_handler(function () {
+            });
+            if ($this->enchanged) {
+                mcrypt_generic_init($this->enmcrypt, $this->key, $this->getIV($this->encryptIV));
+                $this->enchanged = false;
+            }
+
+            // re: {@link http://phpseclib.sourceforge.net/cfb-demo.phps}
+            // using mcrypt's default handing of CFB the above would output two different things.  using phpseclib's
+            // rewritten CFB implementation the above outputs the same thing twice.
+            if ($this->mode == self::MODE_CFB && $this->continuousBuffer) {
+                $block_size = $this->block_size;
+                $iv = &$this->encryptIV;
+                $pos = &$this->enbuffer['pos'];
+                $len = strlen($plaintext);
+                $ciphertext = '';
+                $i = 0;
+                if ($pos) {
+                    $orig_pos = $pos;
+                    $max = $block_size - $pos;
+                    if ($len >= $max) {
+                        $i = $max;
+                        $len -= $max;
+                        $pos = 0;
+                    } else {
+                        $i = $len;
+                        $pos += $len;
+                        $len = 0;
+                    }
+                    $ciphertext = substr($iv, $orig_pos) ^ $plaintext;
+                    $iv = substr_replace($iv, $ciphertext, $orig_pos, $i);
+                    $this->enbuffer['enmcrypt_init'] = true;
+                }
+                if ($len >= $block_size) {
+                    if ($this->enbuffer['enmcrypt_init'] === false || $len > $this->cfb_init_len) {
+                        if ($this->enbuffer['enmcrypt_init'] === true) {
+                            mcrypt_generic_init($this->enmcrypt, $this->key, $iv);
+                            $this->enbuffer['enmcrypt_init'] = false;
+                        }
+                        $ciphertext .= mcrypt_generic($this->enmcrypt, substr($plaintext, $i, $len - $len % $block_size));
+                        $iv = substr($ciphertext, -$block_size);
+                        $len %= $block_size;
+                    } else {
+                        while ($len >= $block_size) {
+                            $iv = mcrypt_generic($this->ecb, $iv) ^ substr($plaintext, $i, $block_size);
+                            $ciphertext .= $iv;
+                            $len -= $block_size;
+                            $i += $block_size;
+                        }
+                    }
+                }
+
+                if ($len) {
+                    $iv = mcrypt_generic($this->ecb, $iv);
+                    $block = $iv ^ substr($plaintext, -$len);
+                    $iv = substr_replace($iv, $block, 0, $len);
+                    $ciphertext .= $block;
+                    $pos = $len;
+                }
+
+                restore_error_handler();
+
+                return $ciphertext;
+            }
+
+            $ciphertext = mcrypt_generic($this->enmcrypt, $plaintext);
+
+            if (!$this->continuousBuffer) {
+                mcrypt_generic_init($this->enmcrypt, $this->key, $this->getIV($this->encryptIV));
+            }
+
+            restore_error_handler();
+
+            return $ciphertext;
+        }
+
+        if ($this->engine === self::ENGINE_EVAL) {
+            $inline = $this->inline_crypt;
+            return $inline('encrypt', $plaintext);
+        }
+
+        $buffer = &$this->enbuffer;
+        $block_size = $this->block_size;
+        $ciphertext = '';
+        switch ($this->mode) {
+            case self::MODE_ECB:
+                for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                    $ciphertext .= $this->encryptBlock(substr($plaintext, $i, $block_size));
+                }
+                break;
+            case self::MODE_CBC:
+                $xor = $this->encryptIV;
+                for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                    $block = substr($plaintext, $i, $block_size);
+                    $block = $this->encryptBlock($block ^ $xor);
+                    $xor = $block;
+                    $ciphertext .= $block;
+                }
+                if ($this->continuousBuffer) {
+                    $this->encryptIV = $xor;
+                }
+                break;
+            case self::MODE_CTR:
+                $xor = $this->encryptIV;
+                if (strlen($buffer['ciphertext'])) {
+                    for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                        $block = substr($plaintext, $i, $block_size);
+                        if (strlen($block) > strlen($buffer['ciphertext'])) {
+                            $buffer['ciphertext'] .= $this->encryptBlock($xor);
+                            Strings::increment_str($xor);
+                        }
+                        $key = Strings::shift($buffer['ciphertext'], $block_size);
+                        $ciphertext .= $block ^ $key;
+                    }
+                } else {
+                    for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                        $block = substr($plaintext, $i, $block_size);
+                        $key = $this->encryptBlock($xor);
+                        Strings::increment_str($xor);
+                        $ciphertext .= $block ^ $key;
+                    }
+                }
+                if ($this->continuousBuffer) {
+                    $this->encryptIV = $xor;
+                    if ($start = strlen($plaintext) % $block_size) {
+                        $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext'];
+                    }
+                }
+                break;
+            case self::MODE_CFB:
+                // cfb loosely routines inspired by openssl's:
+                // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1}
+                if ($this->continuousBuffer) {
+                    $iv = &$this->encryptIV;
+                    $pos = &$buffer['pos'];
+                } else {
+                    $iv = $this->encryptIV;
+                    $pos = 0;
+                }
+                $len = strlen($plaintext);
+                $i = 0;
+                if ($pos) {
+                    $orig_pos = $pos;
+                    $max = $block_size - $pos;
+                    if ($len >= $max) {
+                        $i = $max;
+                        $len -= $max;
+                        $pos = 0;
+                    } else {
+                        $i = $len;
+                        $pos += $len;
+                        $len = 0;
+                    }
+                    // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+                    $ciphertext = substr($iv, $orig_pos) ^ $plaintext;
+                    $iv = substr_replace($iv, $ciphertext, $orig_pos, $i);
+                }
+                while ($len >= $block_size) {
+                    $iv = $this->encryptBlock($iv) ^ substr($plaintext, $i, $block_size);
+                    $ciphertext .= $iv;
+                    $len -= $block_size;
+                    $i += $block_size;
+                }
+                if ($len) {
+                    $iv = $this->encryptBlock($iv);
+                    $block = $iv ^ substr($plaintext, $i);
+                    $iv = substr_replace($iv, $block, 0, $len);
+                    $ciphertext .= $block;
+                    $pos = $len;
+                }
+                break;
+            case self::MODE_CFB8:
+                $ciphertext = '';
+                $len = strlen($plaintext);
+                $iv = $this->encryptIV;
+
+                for ($i = 0; $i < $len; ++$i) {
+                    $ciphertext .= ($c = $plaintext[$i] ^ $this->encryptBlock($iv));
+                    $iv = substr($iv, 1) . $c;
+                }
+
+                if ($this->continuousBuffer) {
+                    if ($len >= $block_size) {
+                        $this->encryptIV = substr($ciphertext, -$block_size);
+                    } else {
+                        $this->encryptIV = substr($this->encryptIV, $len - $block_size) . substr($ciphertext, -$len);
+                    }
+                }
+                break;
+            case self::MODE_OFB8:
+                $ciphertext = '';
+                $len = strlen($plaintext);
+                $iv = $this->encryptIV;
+
+                for ($i = 0; $i < $len; ++$i) {
+                    $xor = $this->encryptBlock($iv);
+                    $ciphertext .= $plaintext[$i] ^ $xor;
+                    $iv = substr($iv, 1) . $xor[0];
+                }
+
+                if ($this->continuousBuffer) {
+                    $this->encryptIV = $iv;
+                }
+                break;
+            case self::MODE_OFB:
+                $xor = $this->encryptIV;
+                if (strlen($buffer['xor'])) {
+                    for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                        $block = substr($plaintext, $i, $block_size);
+                        if (strlen($block) > strlen($buffer['xor'])) {
+                            $xor = $this->encryptBlock($xor);
+                            $buffer['xor'] .= $xor;
+                        }
+                        $key = Strings::shift($buffer['xor'], $block_size);
+                        $ciphertext .= $block ^ $key;
+                    }
+                } else {
+                    for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                        $xor = $this->encryptBlock($xor);
+                        $ciphertext .= substr($plaintext, $i, $block_size) ^ $xor;
+                    }
+                    $key = $xor;
+                }
+                if ($this->continuousBuffer) {
+                    $this->encryptIV = $xor;
+                    if ($start = strlen($plaintext) % $block_size) {
+                        $buffer['xor'] = substr($key, $start) . $buffer['xor'];
+                    }
+                }
+                break;
+            case self::MODE_STREAM:
+                $ciphertext = $this->encryptBlock($plaintext);
+                break;
+        }
+
+        return $ciphertext;
+    }
+
+    /**
+     * Decrypts a message.
+     *
+     * If strlen($ciphertext) is not a multiple of the block size, null bytes will be added to the end of the string until
+     * it is.
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @see self::encrypt()
+     * @param string $ciphertext
+     * @return string $plaintext
+     * @throws \LengthException if we're inside a block cipher and the ciphertext length is not a multiple of the block size
+     */
+    public function decrypt($ciphertext)
+    {
+        if ($this->paddable && strlen($ciphertext) % $this->block_size) {
+            throw new \LengthException('The ciphertext length (' . strlen($ciphertext) . ') needs to be a multiple of the block size (' . $this->block_size . ')');
+        }
+        $this->setup();
+
+        if ($this->mode == self::MODE_GCM || isset($this->poly1305Key)) {
+            if ($this->oldtag === false) {
+                throw new InsufficientSetupException('Authentication Tag has not been set');
+            }
+
+            if (isset($this->poly1305Key)) {
+                $newtag = $this->poly1305($ciphertext);
+            } else {
+                $oldIV = $this->iv;
+                Strings::increment_str($this->iv);
+                $cipher = new static('ctr');
+                $cipher->setKey($this->key);
+                $cipher->setIV($this->iv);
+                $plaintext = $cipher->decrypt($ciphertext);
+
+                $s = $this->ghash(
+                    self::nullPad128($this->aad) .
+                    self::nullPad128($ciphertext) .
+                    self::len64($this->aad) .
+                    self::len64($ciphertext)
+                );
+                $cipher->encryptIV = $this->iv = $this->encryptIV = $this->decryptIV = $oldIV;
+                $newtag = $cipher->encrypt($s);
+            }
+            if ($this->oldtag != substr($newtag, 0, strlen($newtag))) {
+                $cipher = clone $this;
+                unset($cipher->poly1305Key);
+                $this->usePoly1305 = false;
+                $plaintext = $cipher->decrypt($ciphertext);
+                $this->oldtag = false;
+                throw new BadDecryptionException('Derived authentication tag and supplied authentication tag do not match');
+            }
+            $this->oldtag = false;
+            return $plaintext;
+        }
+
+        if ($this->engine === self::ENGINE_OPENSSL) {
+            switch ($this->mode) {
+                case self::MODE_STREAM:
+                    $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+                    break;
+                case self::MODE_ECB:
+                    $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+                    break;
+                case self::MODE_CBC:
+                    $offset = $this->block_size;
+                    $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->decryptIV);
+                    if ($this->continuousBuffer) {
+                        $this->decryptIV = substr($ciphertext, -$offset, $this->block_size);
+                    }
+                    break;
+                case self::MODE_CTR:
+                    $plaintext = $this->openssl_ctr_process($ciphertext, $this->decryptIV, $this->debuffer);
+                    break;
+                case self::MODE_CFB:
+                    // cfb loosely routines inspired by openssl's:
+                    // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1}
+                    $plaintext = '';
+                    if ($this->continuousBuffer) {
+                        $iv = &$this->decryptIV;
+                        $pos = &$this->debuffer['pos'];
+                    } else {
+                        $iv = $this->decryptIV;
+                        $pos = 0;
+                    }
+                    $len = strlen($ciphertext);
+                    $i = 0;
+                    if ($pos) {
+                        $orig_pos = $pos;
+                        $max = $this->block_size - $pos;
+                        if ($len >= $max) {
+                            $i = $max;
+                            $len -= $max;
+                            $pos = 0;
+                        } else {
+                            $i = $len;
+                            $pos += $len;
+                            $len = 0;
+                        }
+                        // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $this->blocksize
+                        $plaintext = substr($iv, $orig_pos) ^ $ciphertext;
+                        $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i);
+                        $ciphertext = substr($ciphertext, $i);
+                    }
+                    $overflow = $len % $this->block_size;
+                    if ($overflow) {
+                        $plaintext .= openssl_decrypt(substr($ciphertext, 0, -$overflow), $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv);
+                        if ($len - $overflow) {
+                            $iv = substr($ciphertext, -$overflow - $this->block_size, -$overflow);
+                        }
+                        $iv = openssl_encrypt(str_repeat("\0", $this->block_size), $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv);
+                        $plaintext .= $iv ^ substr($ciphertext, -$overflow);
+                        $iv = substr_replace($iv, substr($ciphertext, -$overflow), 0, $overflow);
+                        $pos = $overflow;
+                    } elseif ($len) {
+                        $plaintext .= openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv);
+                        $iv = substr($ciphertext, -$this->block_size);
+                    }
+                    break;
+                case self::MODE_CFB8:
+                    $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->decryptIV);
+                    if ($this->continuousBuffer) {
+                        if (($len = strlen($ciphertext)) >= $this->block_size) {
+                            $this->decryptIV = substr($ciphertext, -$this->block_size);
+                        } else {
+                            $this->decryptIV = substr($this->decryptIV, $len - $this->block_size) . substr($ciphertext, -$len);
+                        }
+                    }
+                    break;
+                case self::MODE_OFB8:
+                    $plaintext = '';
+                    $len = strlen($ciphertext);
+                    $iv = $this->decryptIV;
+
+                    for ($i = 0; $i < $len; ++$i) {
+                        $xor = openssl_encrypt($iv, $this->cipher_name_openssl_ecb, $this->key, $this->openssl_options, $this->decryptIV);
+                        $plaintext .= $ciphertext[$i] ^ $xor;
+                        $iv = substr($iv, 1) . $xor[0];
+                    }
+
+                    if ($this->continuousBuffer) {
+                        $this->decryptIV = $iv;
+                    }
+                    break;
+                case self::MODE_OFB:
+                    $plaintext = $this->openssl_ofb_process($ciphertext, $this->decryptIV, $this->debuffer);
+            }
+
+            return $this->paddable ? $this->unpad($plaintext) : $plaintext;
+        }
+
+        if ($this->engine === self::ENGINE_MCRYPT) {
+            set_error_handler(function () {
+            });
+            $block_size = $this->block_size;
+            if ($this->dechanged) {
+                mcrypt_generic_init($this->demcrypt, $this->key, $this->getIV($this->decryptIV));
+                $this->dechanged = false;
+            }
+
+            if ($this->mode == self::MODE_CFB && $this->continuousBuffer) {
+                $iv = &$this->decryptIV;
+                $pos = &$this->debuffer['pos'];
+                $len = strlen($ciphertext);
+                $plaintext = '';
+                $i = 0;
+                if ($pos) {
+                    $orig_pos = $pos;
+                    $max = $block_size - $pos;
+                    if ($len >= $max) {
+                        $i = $max;
+                        $len -= $max;
+                        $pos = 0;
+                    } else {
+                        $i = $len;
+                        $pos += $len;
+                        $len = 0;
+                    }
+                    // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+                    $plaintext = substr($iv, $orig_pos) ^ $ciphertext;
+                    $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i);
+                }
+                if ($len >= $block_size) {
+                    $cb = substr($ciphertext, $i, $len - $len % $block_size);
+                    $plaintext .= mcrypt_generic($this->ecb, $iv . $cb) ^ $cb;
+                    $iv = substr($cb, -$block_size);
+                    $len %= $block_size;
+                }
+                if ($len) {
+                    $iv = mcrypt_generic($this->ecb, $iv);
+                    $plaintext .= $iv ^ substr($ciphertext, -$len);
+                    $iv = substr_replace($iv, substr($ciphertext, -$len), 0, $len);
+                    $pos = $len;
+                }
+
+                restore_error_handler();
+
+                return $plaintext;
+            }
+
+            $plaintext = mdecrypt_generic($this->demcrypt, $ciphertext);
+
+            if (!$this->continuousBuffer) {
+                mcrypt_generic_init($this->demcrypt, $this->key, $this->getIV($this->decryptIV));
+            }
+
+            restore_error_handler();
+
+            return $this->paddable ? $this->unpad($plaintext) : $plaintext;
+        }
+
+        if ($this->engine === self::ENGINE_EVAL) {
+            $inline = $this->inline_crypt;
+            return $inline('decrypt', $ciphertext);
+        }
+
+        $block_size = $this->block_size;
+
+        $buffer = &$this->debuffer;
+        $plaintext = '';
+        switch ($this->mode) {
+            case self::MODE_ECB:
+                for ($i = 0; $i < strlen($ciphertext); $i += $block_size) {
+                    $plaintext .= $this->decryptBlock(substr($ciphertext, $i, $block_size));
+                }
+                break;
+            case self::MODE_CBC:
+                $xor = $this->decryptIV;
+                for ($i = 0; $i < strlen($ciphertext); $i += $block_size) {
+                    $block = substr($ciphertext, $i, $block_size);
+                    $plaintext .= $this->decryptBlock($block) ^ $xor;
+                    $xor = $block;
+                }
+                if ($this->continuousBuffer) {
+                    $this->decryptIV = $xor;
+                }
+                break;
+            case self::MODE_CTR:
+                $xor = $this->decryptIV;
+                if (strlen($buffer['ciphertext'])) {
+                    for ($i = 0; $i < strlen($ciphertext); $i += $block_size) {
+                        $block = substr($ciphertext, $i, $block_size);
+                        if (strlen($block) > strlen($buffer['ciphertext'])) {
+                            $buffer['ciphertext'] .= $this->encryptBlock($xor);
+                            Strings::increment_str($xor);
+                        }
+                        $key = Strings::shift($buffer['ciphertext'], $block_size);
+                        $plaintext .= $block ^ $key;
+                    }
+                } else {
+                    for ($i = 0; $i < strlen($ciphertext); $i += $block_size) {
+                        $block = substr($ciphertext, $i, $block_size);
+                        $key = $this->encryptBlock($xor);
+                        Strings::increment_str($xor);
+                        $plaintext .= $block ^ $key;
+                    }
+                }
+                if ($this->continuousBuffer) {
+                    $this->decryptIV = $xor;
+                    if ($start = strlen($ciphertext) % $block_size) {
+                        $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext'];
+                    }
+                }
+                break;
+            case self::MODE_CFB:
+                if ($this->continuousBuffer) {
+                    $iv = &$this->decryptIV;
+                    $pos = &$buffer['pos'];
+                } else {
+                    $iv = $this->decryptIV;
+                    $pos = 0;
+                }
+                $len = strlen($ciphertext);
+                $i = 0;
+                if ($pos) {
+                    $orig_pos = $pos;
+                    $max = $block_size - $pos;
+                    if ($len >= $max) {
+                        $i = $max;
+                        $len -= $max;
+                        $pos = 0;
+                    } else {
+                        $i = $len;
+                        $pos += $len;
+                        $len = 0;
+                    }
+                    // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+                    $plaintext = substr($iv, $orig_pos) ^ $ciphertext;
+                    $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i);
+                }
+                while ($len >= $block_size) {
+                    $iv = $this->encryptBlock($iv);
+                    $cb = substr($ciphertext, $i, $block_size);
+                    $plaintext .= $iv ^ $cb;
+                    $iv = $cb;
+                    $len -= $block_size;
+                    $i += $block_size;
+                }
+                if ($len) {
+                    $iv = $this->encryptBlock($iv);
+                    $plaintext .= $iv ^ substr($ciphertext, $i);
+                    $iv = substr_replace($iv, substr($ciphertext, $i), 0, $len);
+                    $pos = $len;
+                }
+                break;
+            case self::MODE_CFB8:
+                $plaintext = '';
+                $len = strlen($ciphertext);
+                $iv = $this->decryptIV;
+
+                for ($i = 0; $i < $len; ++$i) {
+                    $plaintext .= $ciphertext[$i] ^ $this->encryptBlock($iv);
+                    $iv = substr($iv, 1) . $ciphertext[$i];
+                }
+
+                if ($this->continuousBuffer) {
+                    if ($len >= $block_size) {
+                        $this->decryptIV = substr($ciphertext, -$block_size);
+                    } else {
+                        $this->decryptIV = substr($this->decryptIV, $len - $block_size) . substr($ciphertext, -$len);
+                    }
+                }
+                break;
+            case self::MODE_OFB8:
+                $plaintext = '';
+                $len = strlen($ciphertext);
+                $iv = $this->decryptIV;
+
+                for ($i = 0; $i < $len; ++$i) {
+                    $xor = $this->encryptBlock($iv);
+                    $plaintext .= $ciphertext[$i] ^ $xor;
+                    $iv = substr($iv, 1) . $xor[0];
+                }
+
+                if ($this->continuousBuffer) {
+                    $this->decryptIV = $iv;
+                }
+                break;
+            case self::MODE_OFB:
+                $xor = $this->decryptIV;
+                if (strlen($buffer['xor'])) {
+                    for ($i = 0; $i < strlen($ciphertext); $i += $block_size) {
+                        $block = substr($ciphertext, $i, $block_size);
+                        if (strlen($block) > strlen($buffer['xor'])) {
+                            $xor = $this->encryptBlock($xor);
+                            $buffer['xor'] .= $xor;
+                        }
+                        $key = Strings::shift($buffer['xor'], $block_size);
+                        $plaintext .= $block ^ $key;
+                    }
+                } else {
+                    for ($i = 0; $i < strlen($ciphertext); $i += $block_size) {
+                        $xor = $this->encryptBlock($xor);
+                        $plaintext .= substr($ciphertext, $i, $block_size) ^ $xor;
+                    }
+                    $key = $xor;
+                }
+                if ($this->continuousBuffer) {
+                    $this->decryptIV = $xor;
+                    if ($start = strlen($ciphertext) % $block_size) {
+                        $buffer['xor'] = substr($key, $start) . $buffer['xor'];
+                    }
+                }
+                break;
+            case self::MODE_STREAM:
+                $plaintext = $this->decryptBlock($ciphertext);
+                break;
+        }
+        return $this->paddable ? $this->unpad($plaintext) : $plaintext;
+    }
+
+    /**
+     * Get the authentication tag
+     *
+     * Only used in GCM or Poly1305 mode
+     *
+     * @see self::encrypt()
+     * @param int $length optional
+     * @return string
+     * @throws \LengthException if $length isn't of a sufficient length
+     * @throws \RuntimeException if GCM mode isn't being used
+     */
+    public function getTag($length = 16)
+    {
+        if ($this->mode != self::MODE_GCM && !$this->usePoly1305) {
+            throw new \BadMethodCallException('Authentication tags are only utilized in GCM mode or with Poly1305');
+        }
+
+        if ($this->newtag === false) {
+            throw new \BadMethodCallException('A tag can only be returned after a round of encryption has been performed');
+        }
+
+        // the tag is 128-bits. it can't be greater than 16 bytes because that's bigger than the tag is. if it
+        // were 0 you might as well be doing CTR and less than 4 provides minimal security that could be trivially
+        // easily brute forced.
+        // see https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=36
+        // for more info
+        if ($length < 4 || $length > 16) {
+            throw new \LengthException('The authentication tag must be between 4 and 16 bytes long');
+        }
+
+        return $length == 16 ?
+            $this->newtag :
+            substr($this->newtag, 0, $length);
+    }
+
+    /**
+     * Sets the authentication tag
+     *
+     * Only used in GCM mode
+     *
+     * @see self::decrypt()
+     * @param string $tag
+     * @throws \LengthException if $length isn't of a sufficient length
+     * @throws \RuntimeException if GCM mode isn't being used
+     */
+    public function setTag($tag)
+    {
+        if ($this->usePoly1305 && !isset($this->poly1305Key) && method_exists($this, 'createPoly1305Key')) {
+            $this->createPoly1305Key();
+        }
+
+        if ($this->mode != self::MODE_GCM && !$this->usePoly1305) {
+            throw new \BadMethodCallException('Authentication tags are only utilized in GCM mode or with Poly1305');
+        }
+
+        $length = strlen($tag);
+        if ($length < 4 || $length > 16) {
+            throw new \LengthException('The authentication tag must be between 4 and 16 bytes long');
+        }
+        $this->oldtag = $tag;
+    }
+
+    /**
+     * Get the IV
+     *
+     * mcrypt requires an IV even if ECB is used
+     *
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @param string $iv
+     * @return string
+     */
+    protected function getIV($iv)
+    {
+        return $this->mode == self::MODE_ECB ? str_repeat("\0", $this->block_size) : $iv;
+    }
+
+    /**
+     * OpenSSL CTR Processor
+     *
+     * PHP's OpenSSL bindings do not operate in continuous mode so we'll wrap around it. Since the keystream
+     * for CTR is the same for both encrypting and decrypting this function is re-used by both SymmetricKey::encrypt()
+     * and SymmetricKey::decrypt(). Also, OpenSSL doesn't implement CTR for all of it's symmetric ciphers so this
+     * function will emulate CTR with ECB when necessary.
+     *
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @param string $plaintext
+     * @param string $encryptIV
+     * @param array $buffer
+     * @return string
+     */
+    private function openssl_ctr_process($plaintext, &$encryptIV, &$buffer)
+    {
+        $ciphertext = '';
+
+        $block_size = $this->block_size;
+        $key = $this->key;
+
+        if ($this->openssl_emulate_ctr) {
+            $xor = $encryptIV;
+            if (strlen($buffer['ciphertext'])) {
+                for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                    $block = substr($plaintext, $i, $block_size);
+                    if (strlen($block) > strlen($buffer['ciphertext'])) {
+                        $buffer['ciphertext'] .= openssl_encrypt($xor, $this->cipher_name_openssl_ecb, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+                    }
+                    Strings::increment_str($xor);
+                    $otp = Strings::shift($buffer['ciphertext'], $block_size);
+                    $ciphertext .= $block ^ $otp;
+                }
+            } else {
+                for ($i = 0; $i < strlen($plaintext); $i += $block_size) {
+                    $block = substr($plaintext, $i, $block_size);
+                    $otp = openssl_encrypt($xor, $this->cipher_name_openssl_ecb, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+                    Strings::increment_str($xor);
+                    $ciphertext .= $block ^ $otp;
+                }
+            }
+            if ($this->continuousBuffer) {
+                $encryptIV = $xor;
+                if ($start = strlen($plaintext) % $block_size) {
+                    $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext'];
+                }
+            }
+
+            return $ciphertext;
+        }
+
+        if (strlen($buffer['ciphertext'])) {
+            $ciphertext = $plaintext ^ Strings::shift($buffer['ciphertext'], strlen($plaintext));
+            $plaintext = substr($plaintext, strlen($ciphertext));
+
+            if (!strlen($plaintext)) {
+                return $ciphertext;
+            }
+        }
+
+        $overflow = strlen($plaintext) % $block_size;
+        if ($overflow) {
+            $plaintext2 = Strings::pop($plaintext, $overflow); // ie. trim $plaintext to a multiple of $block_size and put rest of $plaintext in $plaintext2
+            $encrypted = openssl_encrypt($plaintext . str_repeat("\0", $block_size), $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV);
+            $temp = Strings::pop($encrypted, $block_size);
+            $ciphertext .= $encrypted . ($plaintext2 ^ $temp);
+            if ($this->continuousBuffer) {
+                $buffer['ciphertext'] = substr($temp, $overflow);
+                $encryptIV = $temp;
+            }
+        } elseif (!strlen($buffer['ciphertext'])) {
+            $ciphertext .= openssl_encrypt($plaintext . str_repeat("\0", $block_size), $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV);
+            $temp = Strings::pop($ciphertext, $block_size);
+            if ($this->continuousBuffer) {
+                $encryptIV = $temp;
+            }
+        }
+        if ($this->continuousBuffer) {
+            $encryptIV = openssl_decrypt($encryptIV, $this->cipher_name_openssl_ecb, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING);
+            if ($overflow) {
+                Strings::increment_str($encryptIV);
+            }
+        }
+
+        return $ciphertext;
+    }
+
+    /**
+     * OpenSSL OFB Processor
+     *
+     * PHP's OpenSSL bindings do not operate in continuous mode so we'll wrap around it. Since the keystream
+     * for OFB is the same for both encrypting and decrypting this function is re-used by both SymmetricKey::encrypt()
+     * and SymmetricKey::decrypt().
+     *
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @param string $plaintext
+     * @param string $encryptIV
+     * @param array $buffer
+     * @return string
+     */
+    private function openssl_ofb_process($plaintext, &$encryptIV, &$buffer)
+    {
+        if (strlen($buffer['xor'])) {
+            $ciphertext = $plaintext ^ $buffer['xor'];
+            $buffer['xor'] = substr($buffer['xor'], strlen($ciphertext));
+            $plaintext = substr($plaintext, strlen($ciphertext));
+        } else {
+            $ciphertext = '';
+        }
+
+        $block_size = $this->block_size;
+
+        $len = strlen($plaintext);
+        $key = $this->key;
+        $overflow = $len % $block_size;
+
+        if (strlen($plaintext)) {
+            if ($overflow) {
+                $ciphertext .= openssl_encrypt(substr($plaintext, 0, -$overflow) . str_repeat("\0", $block_size), $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV);
+                $xor = Strings::pop($ciphertext, $block_size);
+                if ($this->continuousBuffer) {
+                    $encryptIV = $xor;
+                }
+                $ciphertext .= Strings::shift($xor, $overflow) ^ substr($plaintext, -$overflow);
+                if ($this->continuousBuffer) {
+                    $buffer['xor'] = $xor;
+                }
+            } else {
+                $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV);
+                if ($this->continuousBuffer) {
+                    $encryptIV = substr($ciphertext, -$block_size) ^ substr($plaintext, -$block_size);
+                }
+            }
+        }
+
+        return $ciphertext;
+    }
+
+    /**
+     * phpseclib <-> OpenSSL Mode Mapper
+     *
+     * May need to be overwritten by classes extending this one in some cases
+     *
+     * @return string
+     */
+    protected function openssl_translate_mode()
+    {
+        switch ($this->mode) {
+            case self::MODE_ECB:
+                return 'ecb';
+            case self::MODE_CBC:
+                return 'cbc';
+            case self::MODE_CTR:
+            case self::MODE_GCM:
+                return 'ctr';
+            case self::MODE_CFB:
+                return 'cfb';
+            case self::MODE_CFB8:
+                return 'cfb8';
+            case self::MODE_OFB:
+                return 'ofb';
+        }
+    }
+
+    /**
+     * Pad "packets".
+     *
+     * Block ciphers working by encrypting between their specified [$this->]block_size at a time
+     * If you ever need to encrypt or decrypt something that isn't of the proper length, it becomes necessary to
+     * pad the input so that it is of the proper length.
+     *
+     * Padding is enabled by default.  Sometimes, however, it is undesirable to pad strings.  Such is the case in SSH,
+     * where "packets" are padded with random bytes before being encrypted.  Unpad these packets and you risk stripping
+     * away characters that shouldn't be stripped away. (SSH knows how many bytes are added because the length is
+     * transmitted separately)
+     *
+     * @see self::disablePadding()
+     */
+    public function enablePadding()
+    {
+        $this->padding = true;
+    }
+
+    /**
+     * Do not pad packets.
+     *
+     * @see self::enablePadding()
+     */
+    public function disablePadding()
+    {
+        $this->padding = false;
+    }
+
+    /**
+     * Treat consecutive "packets" as if they are a continuous buffer.
+     *
+     * Say you have a 32-byte plaintext $plaintext.  Using the default behavior, the two following code snippets
+     * will yield different outputs:
+     *
+     * <code>
+     *    echo $rijndael->encrypt(substr($plaintext,  0, 16));
+     *    echo $rijndael->encrypt(substr($plaintext, 16, 16));
+     * </code>
+     * <code>
+     *    echo $rijndael->encrypt($plaintext);
+     * </code>
+     *
+     * The solution is to enable the continuous buffer.  Although this will resolve the above discrepancy, it creates
+     * another, as demonstrated with the following:
+     *
+     * <code>
+     *    $rijndael->encrypt(substr($plaintext, 0, 16));
+     *    echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16)));
+     * </code>
+     * <code>
+     *    echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16)));
+     * </code>
+     *
+     * With the continuous buffer disabled, these would yield the same output.  With it enabled, they yield different
+     * outputs.  The reason is due to the fact that the initialization vector's change after every encryption /
+     * decryption round when the continuous buffer is enabled.  When it's disabled, they remain constant.
+     *
+     * Put another way, when the continuous buffer is enabled, the state of the \phpseclib3\Crypt\*() object changes after each
+     * encryption / decryption round, whereas otherwise, it'd remain constant.  For this reason, it's recommended that
+     * continuous buffers not be used.  They do offer better security and are, in fact, sometimes required (SSH uses them),
+     * however, they are also less intuitive and more likely to cause you problems.
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @see self::disableContinuousBuffer()
+     */
+    public function enableContinuousBuffer()
+    {
+        if ($this->mode == self::MODE_ECB) {
+            return;
+        }
+
+        if ($this->mode == self::MODE_GCM) {
+            throw new \BadMethodCallException('This mode does not run in continuous mode');
+        }
+
+        $this->continuousBuffer = true;
+
+        $this->setEngine();
+    }
+
+    /**
+     * Treat consecutive packets as if they are a discontinuous buffer.
+     *
+     * The default behavior.
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @see self::enableContinuousBuffer()
+     */
+    public function disableContinuousBuffer()
+    {
+        if ($this->mode == self::MODE_ECB) {
+            return;
+        }
+        if (!$this->continuousBuffer) {
+            return;
+        }
+
+        $this->continuousBuffer = false;
+
+        $this->setEngine();
+    }
+
+    /**
+     * Test for engine validity
+     *
+     * @see self::__construct()
+     * @param int $engine
+     * @return bool
+     */
+    protected function isValidEngineHelper($engine)
+    {
+        switch ($engine) {
+            case self::ENGINE_OPENSSL:
+                $this->openssl_emulate_ctr = false;
+                $result = $this->cipher_name_openssl &&
+                          extension_loaded('openssl');
+                if (!$result) {
+                    return false;
+                }
+
+                $methods = openssl_get_cipher_methods();
+                if (in_array($this->cipher_name_openssl, $methods)) {
+                    return true;
+                }
+                // not all of openssl's symmetric cipher's support ctr. for those
+                // that don't we'll emulate it
+                switch ($this->mode) {
+                    case self::MODE_CTR:
+                        if (in_array($this->cipher_name_openssl_ecb, $methods)) {
+                            $this->openssl_emulate_ctr = true;
+                            return true;
+                        }
+                }
+                return false;
+            case self::ENGINE_MCRYPT:
+                set_error_handler(function () {
+                });
+                $result = $this->cipher_name_mcrypt &&
+                          extension_loaded('mcrypt') &&
+                          in_array($this->cipher_name_mcrypt, mcrypt_list_algorithms());
+                restore_error_handler();
+                return $result;
+            case self::ENGINE_EVAL:
+                return method_exists($this, 'setupInlineCrypt');
+            case self::ENGINE_INTERNAL:
+                return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Test for engine validity
+     *
+     * @see self::__construct()
+     * @param string $engine
+     * @return bool
+     */
+    public function isValidEngine($engine)
+    {
+        static $reverseMap;
+        if (!isset($reverseMap)) {
+            $reverseMap = array_map('strtolower', self::ENGINE_MAP);
+            $reverseMap = array_flip($reverseMap);
+        }
+        $engine = strtolower($engine);
+        if (!isset($reverseMap[$engine])) {
+            return false;
+        }
+
+        return $this->isValidEngineHelper($reverseMap[$engine]);
+    }
+
+    /**
+     * Sets the preferred crypt engine
+     *
+     * Currently, $engine could be:
+     *
+     * - libsodium[very fast]
+     *
+     * - OpenSSL  [very fast]
+     *
+     * - mcrypt   [fast]
+     *
+     * - Eval     [slow]
+     *
+     * - PHP      [slowest]
+     *
+     * If the preferred crypt engine is not available the fastest available one will be used
+     *
+     * @see self::__construct()
+     * @param string $engine
+     */
+    public function setPreferredEngine($engine)
+    {
+        static $reverseMap;
+        if (!isset($reverseMap)) {
+            $reverseMap = array_map('strtolower', self::ENGINE_MAP);
+            $reverseMap = array_flip($reverseMap);
+        }
+        $engine = is_string($engine) ? strtolower($engine) : '';
+        $this->preferredEngine = isset($reverseMap[$engine]) ? $reverseMap[$engine] : self::ENGINE_LIBSODIUM;
+
+        $this->setEngine();
+    }
+
+    /**
+     * Returns the engine currently being utilized
+     *
+     * @see self::setEngine()
+     */
+    public function getEngine()
+    {
+        return self::ENGINE_MAP[$this->engine];
+    }
+
+    /**
+     * Sets the engine as appropriate
+     *
+     * @see self::__construct()
+     */
+    protected function setEngine()
+    {
+        $this->engine = null;
+
+        $candidateEngines = [
+            self::ENGINE_LIBSODIUM,
+            self::ENGINE_OPENSSL_GCM,
+            self::ENGINE_OPENSSL,
+            self::ENGINE_MCRYPT,
+            self::ENGINE_EVAL
+        ];
+        if (isset($this->preferredEngine)) {
+            $temp = [$this->preferredEngine];
+            $candidateEngines = array_merge(
+                $temp,
+                array_diff($candidateEngines, $temp)
+            );
+        }
+        foreach ($candidateEngines as $engine) {
+            if ($this->isValidEngineHelper($engine)) {
+                $this->engine = $engine;
+                break;
+            }
+        }
+        if (!$this->engine) {
+            $this->engine = self::ENGINE_INTERNAL;
+        }
+
+        if ($this->engine != self::ENGINE_MCRYPT && $this->enmcrypt) {
+            set_error_handler(function () {
+            });
+            // Closing the current mcrypt resource(s). _mcryptSetup() will, if needed,
+            // (re)open them with the module named in $this->cipher_name_mcrypt
+            mcrypt_module_close($this->enmcrypt);
+            mcrypt_module_close($this->demcrypt);
+            $this->enmcrypt = null;
+            $this->demcrypt = null;
+
+            if ($this->ecb) {
+                mcrypt_module_close($this->ecb);
+                $this->ecb = null;
+            }
+            restore_error_handler();
+        }
+
+        $this->changed = $this->nonIVChanged = true;
+    }
+
+    /**
+     * Encrypts a block
+     *
+     * Note: Must be extended by the child \phpseclib3\Crypt\* class
+     *
+     * @param string $in
+     * @return string
+     */
+    abstract protected function encryptBlock($in);
+
+    /**
+     * Decrypts a block
+     *
+     * Note: Must be extended by the child \phpseclib3\Crypt\* class
+     *
+     * @param string $in
+     * @return string
+     */
+    abstract protected function decryptBlock($in);
+
+    /**
+     * Setup the key (expansion)
+     *
+     * Only used if $engine == self::ENGINE_INTERNAL
+     *
+     * Note: Must extend by the child \phpseclib3\Crypt\* class
+     *
+     * @see self::setup()
+     */
+    abstract protected function setupKey();
+
+    /**
+     * Setup the self::ENGINE_INTERNAL $engine
+     *
+     * (re)init, if necessary, the internal cipher $engine and flush all $buffers
+     * Used (only) if $engine == self::ENGINE_INTERNAL
+     *
+     * _setup() will be called each time if $changed === true
+     * typically this happens when using one or more of following public methods:
+     *
+     * - setKey()
+     *
+     * - setIV()
+     *
+     * - disableContinuousBuffer()
+     *
+     * - First run of encrypt() / decrypt() with no init-settings
+     *
+     * {@internal setup() is always called before en/decryption.}
+     *
+     * {@internal Could, but not must, extend by the child Crypt_* class}
+     *
+     * @see self::setKey()
+     * @see self::setIV()
+     * @see self::disableContinuousBuffer()
+     */
+    protected function setup()
+    {
+        if (!$this->changed) {
+            return;
+        }
+
+        $this->changed = false;
+
+        if ($this->usePoly1305 && !isset($this->poly1305Key) && method_exists($this, 'createPoly1305Key')) {
+            $this->createPoly1305Key();
+        }
+
+        $this->enbuffer = $this->debuffer = ['ciphertext' => '', 'xor' => '', 'pos' => 0, 'enmcrypt_init' => true];
+        //$this->newtag = $this->oldtag = false;
+
+        if ($this->usesNonce()) {
+            if ($this->nonce === false) {
+                throw new InsufficientSetupException('No nonce has been defined');
+            }
+            if ($this->mode == self::MODE_GCM && !in_array($this->engine, [self::ENGINE_LIBSODIUM, self::ENGINE_OPENSSL_GCM])) {
+                $this->setupGCM();
+            }
+        } else {
+            $this->iv = $this->origIV;
+        }
+
+        if ($this->iv === false && !in_array($this->mode, [self::MODE_STREAM, self::MODE_ECB])) {
+            if ($this->mode != self::MODE_GCM || !in_array($this->engine, [self::ENGINE_LIBSODIUM, self::ENGINE_OPENSSL_GCM])) {
+                throw new InsufficientSetupException('No IV has been defined');
+            }
+        }
+
+        if ($this->key === false) {
+            throw new InsufficientSetupException('No key has been defined');
+        }
+
+        $this->encryptIV = $this->decryptIV = $this->iv;
+
+        switch ($this->engine) {
+            case self::ENGINE_MCRYPT:
+                $this->enchanged = $this->dechanged = true;
+
+                set_error_handler(function () {
+                });
+
+                if (!isset($this->enmcrypt)) {
+                    static $mcrypt_modes = [
+                        self::MODE_CTR    => 'ctr',
+                        self::MODE_ECB    => MCRYPT_MODE_ECB,
+                        self::MODE_CBC    => MCRYPT_MODE_CBC,
+                        self::MODE_CFB    => 'ncfb',
+                        self::MODE_CFB8   => MCRYPT_MODE_CFB,
+                        self::MODE_OFB    => MCRYPT_MODE_NOFB,
+                        self::MODE_OFB8   => MCRYPT_MODE_OFB,
+                        self::MODE_STREAM => MCRYPT_MODE_STREAM,
+                    ];
+
+                    $this->demcrypt = mcrypt_module_open($this->cipher_name_mcrypt, '', $mcrypt_modes[$this->mode], '');
+                    $this->enmcrypt = mcrypt_module_open($this->cipher_name_mcrypt, '', $mcrypt_modes[$this->mode], '');
+
+                    // we need the $ecb mcrypt resource (only) in MODE_CFB with enableContinuousBuffer()
+                    // to workaround mcrypt's broken ncfb implementation in buffered mode
+                    // see: {@link http://phpseclib.sourceforge.net/cfb-demo.phps}
+                    if ($this->mode == self::MODE_CFB) {
+                        $this->ecb = mcrypt_module_open($this->cipher_name_mcrypt, '', MCRYPT_MODE_ECB, '');
+                    }
+                } // else should mcrypt_generic_deinit be called?
+
+                if ($this->mode == self::MODE_CFB) {
+                    mcrypt_generic_init($this->ecb, $this->key, str_repeat("\0", $this->block_size));
+                }
+
+                restore_error_handler();
+
+                break;
+            case self::ENGINE_INTERNAL:
+                $this->setupKey();
+                break;
+            case self::ENGINE_EVAL:
+                if ($this->nonIVChanged) {
+                    $this->setupKey();
+                    $this->setupInlineCrypt();
+                }
+        }
+
+        $this->nonIVChanged = false;
+    }
+
+    /**
+     * Pads a string
+     *
+     * Pads a string using the RSA PKCS padding standards so that its length is a multiple of the blocksize.
+     * $this->block_size - (strlen($text) % $this->block_size) bytes are added, each of which is equal to
+     * chr($this->block_size - (strlen($text) % $this->block_size)
+     *
+     * If padding is disabled and $text is not a multiple of the blocksize, the string will be padded regardless
+     * and padding will, hence forth, be enabled.
+     *
+     * @see self::unpad()
+     * @param string $text
+     * @throws \LengthException if padding is disabled and the plaintext's length is not a multiple of the block size
+     * @return string
+     */
+    protected function pad($text)
+    {
+        $length = strlen($text);
+
+        if (!$this->padding) {
+            if ($length % $this->block_size == 0) {
+                return $text;
+            } else {
+                throw new \LengthException("The plaintext's length ($length) is not a multiple of the block size ({$this->block_size}). Try enabling padding.");
+            }
+        }
+
+        $pad = $this->block_size - ($length % $this->block_size);
+
+        return str_pad($text, $length + $pad, chr($pad));
+    }
+
+    /**
+     * Unpads a string.
+     *
+     * If padding is enabled and the reported padding length is invalid the encryption key will be assumed to be wrong
+     * and false will be returned.
+     *
+     * @see self::pad()
+     * @param string $text
+     * @throws \LengthException if the ciphertext's length is not a multiple of the block size
+     * @return string
+     */
+    protected function unpad($text)
+    {
+        if (!$this->padding) {
+            return $text;
+        }
+
+        $length = ord($text[strlen($text) - 1]);
+
+        if (!$length || $length > $this->block_size) {
+            throw new BadDecryptionException("The ciphertext has an invalid padding length ($length) compared to the block size ({$this->block_size})");
+        }
+
+        return substr($text, 0, -$length);
+    }
+
+    /**
+     * Setup the performance-optimized function for de/encrypt()
+     *
+     * Stores the created (or existing) callback function-name
+     * in $this->inline_crypt
+     *
+     * Internally for phpseclib developers:
+     *
+     *     _setupInlineCrypt() would be called only if:
+     *
+     *     - $this->engine === self::ENGINE_EVAL
+     *
+     *     - each time on _setup(), after(!) _setupKey()
+     *
+     *
+     *     This ensures that _setupInlineCrypt() has always a
+     *     full ready2go initializated internal cipher $engine state
+     *     where, for example, the keys already expanded,
+     *     keys/block_size calculated and such.
+     *
+     *     It is, each time if called, the responsibility of _setupInlineCrypt():
+     *
+     *     - to set $this->inline_crypt to a valid and fully working callback function
+     *       as a (faster) replacement for encrypt() / decrypt()
+     *
+     *     - NOT to create unlimited callback functions (for memory reasons!)
+     *       no matter how often _setupInlineCrypt() would be called. At some
+     *       point of amount they must be generic re-useable.
+     *
+     *     - the code of _setupInlineCrypt() it self,
+     *       and the generated callback code,
+     *       must be, in following order:
+     *       - 100% safe
+     *       - 100% compatible to encrypt()/decrypt()
+     *       - using only php5+ features/lang-constructs/php-extensions if
+     *         compatibility (down to php4) or fallback is provided
+     *       - readable/maintainable/understandable/commented and... not-cryptic-styled-code :-)
+     *       - >= 10% faster than encrypt()/decrypt() [which is, by the way,
+     *         the reason for the existence of _setupInlineCrypt() :-)]
+     *       - memory-nice
+     *       - short (as good as possible)
+     *
+     * Note: - _setupInlineCrypt() is using _createInlineCryptFunction() to create the full callback function code.
+     *       - In case of using inline crypting, _setupInlineCrypt() must extend by the child \phpseclib3\Crypt\* class.
+     *       - The following variable names are reserved:
+     *         - $_*  (all variable names prefixed with an underscore)
+     *         - $self (object reference to it self. Do not use $this, but $self instead)
+     *         - $in (the content of $in has to en/decrypt by the generated code)
+     *       - The callback function should not use the 'return' statement, but en/decrypt'ing the content of $in only
+     *
+     * {@internal If a Crypt_* class providing inline crypting it must extend _setupInlineCrypt()}
+     *
+     * @see self::setup()
+     * @see self::createInlineCryptFunction()
+     * @see self::encrypt()
+     * @see self::decrypt()
+     */
+    //protected function setupInlineCrypt();
+
+    /**
+     * Creates the performance-optimized function for en/decrypt()
+     *
+     * Internally for phpseclib developers:
+     *
+     *    _createInlineCryptFunction():
+     *
+     *    - merge the $cipher_code [setup'ed by _setupInlineCrypt()]
+     *      with the current [$this->]mode of operation code
+     *
+     *    - create the $inline function, which called by encrypt() / decrypt()
+     *      as its replacement to speed up the en/decryption operations.
+     *
+     *    - return the name of the created $inline callback function
+     *
+     *    - used to speed up en/decryption
+     *
+     *
+     *
+     *    The main reason why can speed up things [up to 50%] this way are:
+     *
+     *    - using variables more effective then regular.
+     *      (ie no use of expensive arrays but integers $k_0, $k_1 ...
+     *      or even, for example, the pure $key[] values hardcoded)
+     *
+     *    - avoiding 1000's of function calls of ie _encryptBlock()
+     *      but inlining the crypt operations.
+     *      in the mode of operation for() loop.
+     *
+     *    - full loop unroll the (sometimes key-dependent) rounds
+     *      avoiding this way ++$i counters and runtime-if's etc...
+     *
+     *    The basic code architectur of the generated $inline en/decrypt()
+     *    lambda function, in pseudo php, is:
+     *
+     *    <code>
+     *    +----------------------------------------------------------------------------------------------+
+     *    | callback $inline = create_function:                                                          |
+     *    | lambda_function_0001_crypt_ECB($action, $text)                                               |
+     *    | {                                                                                            |
+     *    |     INSERT PHP CODE OF:                                                                      |
+     *    |     $cipher_code['init_crypt'];                  // general init code.                       |
+     *    |                                                  // ie: $sbox'es declarations used for       |
+     *    |                                                  //     encrypt and decrypt'ing.             |
+     *    |                                                                                              |
+     *    |     switch ($action) {                                                                       |
+     *    |         case 'encrypt':                                                                      |
+     *    |             INSERT PHP CODE OF:                                                              |
+     *    |             $cipher_code['init_encrypt'];       // encrypt sepcific init code.               |
+     *    |                                                    ie: specified $key or $box                |
+     *    |                                                        declarations for encrypt'ing.         |
+     *    |                                                                                              |
+     *    |             foreach ($ciphertext) {                                                          |
+     *    |                 $in = $block_size of $ciphertext;                                            |
+     *    |                                                                                              |
+     *    |                 INSERT PHP CODE OF:                                                          |
+     *    |                 $cipher_code['encrypt_block'];  // encrypt's (string) $in, which is always:  |
+     *    |                                                 // strlen($in) == $this->block_size          |
+     *    |                                                 // here comes the cipher algorithm in action |
+     *    |                                                 // for encryption.                           |
+     *    |                                                 // $cipher_code['encrypt_block'] has to      |
+     *    |                                                 // encrypt the content of the $in variable   |
+     *    |                                                                                              |
+     *    |                 $plaintext .= $in;                                                           |
+     *    |             }                                                                                |
+     *    |             return $plaintext;                                                               |
+     *    |                                                                                              |
+     *    |         case 'decrypt':                                                                      |
+     *    |             INSERT PHP CODE OF:                                                              |
+     *    |             $cipher_code['init_decrypt'];       // decrypt sepcific init code                |
+     *    |                                                    ie: specified $key or $box                |
+     *    |                                                        declarations for decrypt'ing.         |
+     *    |             foreach ($plaintext) {                                                           |
+     *    |                 $in = $block_size of $plaintext;                                             |
+     *    |                                                                                              |
+     *    |                 INSERT PHP CODE OF:                                                          |
+     *    |                 $cipher_code['decrypt_block'];  // decrypt's (string) $in, which is always   |
+     *    |                                                 // strlen($in) == $this->block_size          |
+     *    |                                                 // here comes the cipher algorithm in action |
+     *    |                                                 // for decryption.                           |
+     *    |                                                 // $cipher_code['decrypt_block'] has to      |
+     *    |                                                 // decrypt the content of the $in variable   |
+     *    |                 $ciphertext .= $in;                                                          |
+     *    |             }                                                                                |
+     *    |             return $ciphertext;                                                              |
+     *    |     }                                                                                        |
+     *    | }                                                                                            |
+     *    +----------------------------------------------------------------------------------------------+
+     *    </code>
+     *
+     *    See also the \phpseclib3\Crypt\*::_setupInlineCrypt()'s for
+     *    productive inline $cipher_code's how they works.
+     *
+     *    Structure of:
+     *    <code>
+     *    $cipher_code = [
+     *        'init_crypt'    => (string) '', // optional
+     *        'init_encrypt'  => (string) '', // optional
+     *        'init_decrypt'  => (string) '', // optional
+     *        'encrypt_block' => (string) '', // required
+     *        'decrypt_block' => (string) ''  // required
+     *    ];
+     *    </code>
+     *
+     * @see self::setupInlineCrypt()
+     * @see self::encrypt()
+     * @see self::decrypt()
+     * @param array $cipher_code
+     * @return string (the name of the created callback function)
+     */
+    protected function createInlineCryptFunction($cipher_code)
+    {
+        $block_size = $this->block_size;
+
+        // optional
+        $init_crypt    = isset($cipher_code['init_crypt'])    ? $cipher_code['init_crypt']    : '';
+        $init_encrypt  = isset($cipher_code['init_encrypt'])  ? $cipher_code['init_encrypt']  : '';
+        $init_decrypt  = isset($cipher_code['init_decrypt'])  ? $cipher_code['init_decrypt']  : '';
+        // required
+        $encrypt_block = $cipher_code['encrypt_block'];
+        $decrypt_block = $cipher_code['decrypt_block'];
+
+        // Generating mode of operation inline code,
+        // merged with the $cipher_code algorithm
+        // for encrypt- and decryption.
+        switch ($this->mode) {
+            case self::MODE_ECB:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_plaintext_len = strlen($_text);
+
+                    for ($_i = 0; $_i < $_plaintext_len; $_i+= ' . $block_size . ') {
+                        $in = substr($_text, $_i, ' . $block_size . ');
+                        ' . $encrypt_block . '
+                        $_ciphertext.= $in;
+                    }
+
+                    return $_ciphertext;
+                    ';
+
+                $decrypt = $init_decrypt . '
+                    $_plaintext = "";
+                    $_text = str_pad($_text, strlen($_text) + (' . $block_size . ' - strlen($_text) % ' . $block_size . ') % ' . $block_size . ', chr(0));
+                    $_ciphertext_len = strlen($_text);
+
+                    for ($_i = 0; $_i < $_ciphertext_len; $_i+= ' . $block_size . ') {
+                        $in = substr($_text, $_i, ' . $block_size . ');
+                        ' . $decrypt_block . '
+                        $_plaintext.= $in;
+                    }
+
+                    return $this->unpad($_plaintext);
+                    ';
+                break;
+            case self::MODE_CTR:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_plaintext_len = strlen($_text);
+                    $_xor = $this->encryptIV;
+                    $_buffer = &$this->enbuffer;
+                    if (strlen($_buffer["ciphertext"])) {
+                        for ($_i = 0; $_i < $_plaintext_len; $_i+= ' . $block_size . ') {
+                            $_block = substr($_text, $_i, ' . $block_size . ');
+                            if (strlen($_block) > strlen($_buffer["ciphertext"])) {
+                                $in = $_xor;
+                                ' . $encrypt_block . '
+                                \phpseclib3\Common\Functions\Strings::increment_str($_xor);
+                                $_buffer["ciphertext"].= $in;
+                            }
+                            $_key = \phpseclib3\Common\Functions\Strings::shift($_buffer["ciphertext"], ' . $block_size . ');
+                            $_ciphertext.= $_block ^ $_key;
+                        }
+                    } else {
+                        for ($_i = 0; $_i < $_plaintext_len; $_i+= ' . $block_size . ') {
+                            $_block = substr($_text, $_i, ' . $block_size . ');
+                            $in = $_xor;
+                            ' . $encrypt_block . '
+                            \phpseclib3\Common\Functions\Strings::increment_str($_xor);
+                            $_key = $in;
+                            $_ciphertext.= $_block ^ $_key;
+                        }
+                    }
+                    if ($this->continuousBuffer) {
+                        $this->encryptIV = $_xor;
+                        if ($_start = $_plaintext_len % ' . $block_size . ') {
+                            $_buffer["ciphertext"] = substr($_key, $_start) . $_buffer["ciphertext"];
+                        }
+                    }
+
+                    return $_ciphertext;
+                ';
+
+                $decrypt = $init_encrypt . '
+                    $_plaintext = "";
+                    $_ciphertext_len = strlen($_text);
+                    $_xor = $this->decryptIV;
+                    $_buffer = &$this->debuffer;
+
+                    if (strlen($_buffer["ciphertext"])) {
+                        for ($_i = 0; $_i < $_ciphertext_len; $_i+= ' . $block_size . ') {
+                            $_block = substr($_text, $_i, ' . $block_size . ');
+                            if (strlen($_block) > strlen($_buffer["ciphertext"])) {
+                                $in = $_xor;
+                                ' . $encrypt_block . '
+                                \phpseclib3\Common\Functions\Strings::increment_str($_xor);
+                                $_buffer["ciphertext"].= $in;
+                            }
+                            $_key = \phpseclib3\Common\Functions\Strings::shift($_buffer["ciphertext"], ' . $block_size . ');
+                            $_plaintext.= $_block ^ $_key;
+                        }
+                    } else {
+                        for ($_i = 0; $_i < $_ciphertext_len; $_i+= ' . $block_size . ') {
+                            $_block = substr($_text, $_i, ' . $block_size . ');
+                            $in = $_xor;
+                            ' . $encrypt_block . '
+                            \phpseclib3\Common\Functions\Strings::increment_str($_xor);
+                            $_key = $in;
+                            $_plaintext.= $_block ^ $_key;
+                        }
+                    }
+                    if ($this->continuousBuffer) {
+                        $this->decryptIV = $_xor;
+                        if ($_start = $_ciphertext_len % ' . $block_size . ') {
+                            $_buffer["ciphertext"] = substr($_key, $_start) . $_buffer["ciphertext"];
+                        }
+                    }
+
+                    return $_plaintext;
+                    ';
+                break;
+            case self::MODE_CFB:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_buffer = &$this->enbuffer;
+
+                    if ($this->continuousBuffer) {
+                        $_iv = &$this->encryptIV;
+                        $_pos = &$_buffer["pos"];
+                    } else {
+                        $_iv = $this->encryptIV;
+                        $_pos = 0;
+                    }
+                    $_len = strlen($_text);
+                    $_i = 0;
+                    if ($_pos) {
+                        $_orig_pos = $_pos;
+                        $_max = ' . $block_size . ' - $_pos;
+                        if ($_len >= $_max) {
+                            $_i = $_max;
+                            $_len-= $_max;
+                            $_pos = 0;
+                        } else {
+                            $_i = $_len;
+                            $_pos+= $_len;
+                            $_len = 0;
+                        }
+                        $_ciphertext = substr($_iv, $_orig_pos) ^ $_text;
+                        $_iv = substr_replace($_iv, $_ciphertext, $_orig_pos, $_i);
+                    }
+                    while ($_len >= ' . $block_size . ') {
+                        $in = $_iv;
+                        ' . $encrypt_block . ';
+                        $_iv = $in ^ substr($_text, $_i, ' . $block_size . ');
+                        $_ciphertext.= $_iv;
+                        $_len-= ' . $block_size . ';
+                        $_i+= ' . $block_size . ';
+                    }
+                    if ($_len) {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_iv = $in;
+                        $_block = $_iv ^ substr($_text, $_i);
+                        $_iv = substr_replace($_iv, $_block, 0, $_len);
+                        $_ciphertext.= $_block;
+                        $_pos = $_len;
+                    }
+                    return $_ciphertext;
+                ';
+
+                $decrypt = $init_encrypt . '
+                    $_plaintext = "";
+                    $_buffer = &$this->debuffer;
+
+                    if ($this->continuousBuffer) {
+                        $_iv = &$this->decryptIV;
+                        $_pos = &$_buffer["pos"];
+                    } else {
+                        $_iv = $this->decryptIV;
+                        $_pos = 0;
+                    }
+                    $_len = strlen($_text);
+                    $_i = 0;
+                    if ($_pos) {
+                        $_orig_pos = $_pos;
+                        $_max = ' . $block_size . ' - $_pos;
+                        if ($_len >= $_max) {
+                            $_i = $_max;
+                            $_len-= $_max;
+                            $_pos = 0;
+                        } else {
+                            $_i = $_len;
+                            $_pos+= $_len;
+                            $_len = 0;
+                        }
+                        $_plaintext = substr($_iv, $_orig_pos) ^ $_text;
+                        $_iv = substr_replace($_iv, substr($_text, 0, $_i), $_orig_pos, $_i);
+                    }
+                    while ($_len >= ' . $block_size . ') {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_iv = $in;
+                        $cb = substr($_text, $_i, ' . $block_size . ');
+                        $_plaintext.= $_iv ^ $cb;
+                        $_iv = $cb;
+                        $_len-= ' . $block_size . ';
+                        $_i+= ' . $block_size . ';
+                    }
+                    if ($_len) {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_iv = $in;
+                        $_plaintext.= $_iv ^ substr($_text, $_i);
+                        $_iv = substr_replace($_iv, substr($_text, $_i), 0, $_len);
+                        $_pos = $_len;
+                    }
+
+                    return $_plaintext;
+                    ';
+                break;
+            case self::MODE_CFB8:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_len = strlen($_text);
+                    $_iv = $this->encryptIV;
+
+                    for ($_i = 0; $_i < $_len; ++$_i) {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_ciphertext .= ($_c = $_text[$_i] ^ $in);
+                        $_iv = substr($_iv, 1) . $_c;
+                    }
+
+                    if ($this->continuousBuffer) {
+                        if ($_len >= ' . $block_size . ') {
+                            $this->encryptIV = substr($_ciphertext, -' . $block_size . ');
+                        } else {
+                            $this->encryptIV = substr($this->encryptIV, $_len - ' . $block_size . ') . substr($_ciphertext, -$_len);
+                        }
+                    }
+
+                    return $_ciphertext;
+                    ';
+                $decrypt = $init_encrypt . '
+                    $_plaintext = "";
+                    $_len = strlen($_text);
+                    $_iv = $this->decryptIV;
+
+                    for ($_i = 0; $_i < $_len; ++$_i) {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_plaintext .= $_text[$_i] ^ $in;
+                        $_iv = substr($_iv, 1) . $_text[$_i];
+                    }
+
+                    if ($this->continuousBuffer) {
+                        if ($_len >= ' . $block_size . ') {
+                            $this->decryptIV = substr($_text, -' . $block_size . ');
+                        } else {
+                            $this->decryptIV = substr($this->decryptIV, $_len - ' . $block_size . ') . substr($_text, -$_len);
+                        }
+                    }
+
+                    return $_plaintext;
+                    ';
+                break;
+            case self::MODE_OFB8:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_len = strlen($_text);
+                    $_iv = $this->encryptIV;
+
+                    for ($_i = 0; $_i < $_len; ++$_i) {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_ciphertext.= $_text[$_i] ^ $in;
+                        $_iv = substr($_iv, 1) . $in[0];
+                    }
+
+                    if ($this->continuousBuffer) {
+                        $this->encryptIV = $_iv;
+                    }
+
+                    return $_ciphertext;
+                    ';
+                $decrypt = $init_encrypt . '
+                    $_plaintext = "";
+                    $_len = strlen($_text);
+                    $_iv = $this->decryptIV;
+
+                    for ($_i = 0; $_i < $_len; ++$_i) {
+                        $in = $_iv;
+                        ' . $encrypt_block . '
+                        $_plaintext.= $_text[$_i] ^ $in;
+                        $_iv = substr($_iv, 1) . $in[0];
+                    }
+
+                    if ($this->continuousBuffer) {
+                        $this->decryptIV = $_iv;
+                    }
+
+                    return $_plaintext;
+                    ';
+                break;
+            case self::MODE_OFB:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_plaintext_len = strlen($_text);
+                    $_xor = $this->encryptIV;
+                    $_buffer = &$this->enbuffer;
+
+                    if (strlen($_buffer["xor"])) {
+                        for ($_i = 0; $_i < $_plaintext_len; $_i+= ' . $block_size . ') {
+                            $_block = substr($_text, $_i, ' . $block_size . ');
+                            if (strlen($_block) > strlen($_buffer["xor"])) {
+                                $in = $_xor;
+                                ' . $encrypt_block . '
+                                $_xor = $in;
+                                $_buffer["xor"].= $_xor;
+                            }
+                            $_key = \phpseclib3\Common\Functions\Strings::shift($_buffer["xor"], ' . $block_size . ');
+                            $_ciphertext.= $_block ^ $_key;
+                        }
+                    } else {
+                        for ($_i = 0; $_i < $_plaintext_len; $_i+= ' . $block_size . ') {
+                            $in = $_xor;
+                            ' . $encrypt_block . '
+                            $_xor = $in;
+                            $_ciphertext.= substr($_text, $_i, ' . $block_size . ') ^ $_xor;
+                        }
+                        $_key = $_xor;
+                    }
+                    if ($this->continuousBuffer) {
+                        $this->encryptIV = $_xor;
+                        if ($_start = $_plaintext_len % ' . $block_size . ') {
+                             $_buffer["xor"] = substr($_key, $_start) . $_buffer["xor"];
+                        }
+                    }
+                    return $_ciphertext;
+                    ';
+
+                $decrypt = $init_encrypt . '
+                    $_plaintext = "";
+                    $_ciphertext_len = strlen($_text);
+                    $_xor = $this->decryptIV;
+                    $_buffer = &$this->debuffer;
+
+                    if (strlen($_buffer["xor"])) {
+                        for ($_i = 0; $_i < $_ciphertext_len; $_i+= ' . $block_size . ') {
+                            $_block = substr($_text, $_i, ' . $block_size . ');
+                            if (strlen($_block) > strlen($_buffer["xor"])) {
+                                $in = $_xor;
+                                ' . $encrypt_block . '
+                                $_xor = $in;
+                                $_buffer["xor"].= $_xor;
+                            }
+                            $_key = \phpseclib3\Common\Functions\Strings::shift($_buffer["xor"], ' . $block_size . ');
+                            $_plaintext.= $_block ^ $_key;
+                        }
+                    } else {
+                        for ($_i = 0; $_i < $_ciphertext_len; $_i+= ' . $block_size . ') {
+                            $in = $_xor;
+                            ' . $encrypt_block . '
+                            $_xor = $in;
+                            $_plaintext.= substr($_text, $_i, ' . $block_size . ') ^ $_xor;
+                        }
+                        $_key = $_xor;
+                    }
+                    if ($this->continuousBuffer) {
+                        $this->decryptIV = $_xor;
+                        if ($_start = $_ciphertext_len % ' . $block_size . ') {
+                             $_buffer["xor"] = substr($_key, $_start) . $_buffer["xor"];
+                        }
+                    }
+                    return $_plaintext;
+                    ';
+                break;
+            case self::MODE_STREAM:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    ' . $encrypt_block . '
+                    return $_ciphertext;
+                    ';
+                $decrypt = $init_decrypt . '
+                    $_plaintext = "";
+                    ' . $decrypt_block . '
+                    return $_plaintext;
+                    ';
+                break;
+            // case self::MODE_CBC:
+            default:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_plaintext_len = strlen($_text);
+
+                    $in = $this->encryptIV;
+
+                    for ($_i = 0; $_i < $_plaintext_len; $_i+= ' . $block_size . ') {
+                        $in = substr($_text, $_i, ' . $block_size . ') ^ $in;
+                        ' . $encrypt_block . '
+                        $_ciphertext.= $in;
+                    }
+
+                    if ($this->continuousBuffer) {
+                        $this->encryptIV = $in;
+                    }
+
+                    return $_ciphertext;
+                    ';
+
+                $decrypt = $init_decrypt . '
+                    $_plaintext = "";
+                    $_text = str_pad($_text, strlen($_text) + (' . $block_size . ' - strlen($_text) % ' . $block_size . ') % ' . $block_size . ', chr(0));
+                    $_ciphertext_len = strlen($_text);
+
+                    $_iv = $this->decryptIV;
+
+                    for ($_i = 0; $_i < $_ciphertext_len; $_i+= ' . $block_size . ') {
+                        $in = $_block = substr($_text, $_i, ' . $block_size . ');
+                        ' . $decrypt_block . '
+                        $_plaintext.= $in ^ $_iv;
+                        $_iv = $_block;
+                    }
+
+                    if ($this->continuousBuffer) {
+                        $this->decryptIV = $_iv;
+                    }
+
+                    return $this->unpad($_plaintext);
+                    ';
+                break;
+        }
+
+        // Before discrediting this, please read the following:
+        // @see https://github.com/phpseclib/phpseclib/issues/1293
+        // @see https://github.com/phpseclib/phpseclib/pull/1143
+        eval('$func = function ($_action, $_text) { ' . $init_crypt . 'if ($_action == "encrypt") { ' . $encrypt . ' } else { ' . $decrypt . ' }};');
+
+        return \Closure::bind($func, $this, static::class);
+    }
+
+    /**
+     * Convert float to int
+     *
+     * On ARM CPUs converting floats to ints doesn't always work
+     *
+     * @param string $x
+     * @return int
+     */
+    protected static function safe_intval($x)
+    {
+        if (is_int($x)) {
+            return $x;
+        }
+
+        if (self::$use_reg_intval) {
+            return PHP_INT_SIZE == 4 && PHP_VERSION_ID >= 80100 ? intval($x) : $x;
+        }
+
+        return (fmod($x, 0x80000000) & 0x7FFFFFFF) |
+            ((fmod(floor($x / 0x80000000), 2) & 1) << 31);
+    }
+
+    /**
+     * eval()'able string for in-line float to int
+     *
+     * @return string
+     */
+    protected static function safe_intval_inline()
+    {
+        if (self::$use_reg_intval) {
+            return PHP_INT_SIZE == 4 && PHP_VERSION_ID >= 80100 ? 'intval(%s)' : '%s';
+        }
+
+        $safeint = '(is_int($temp = %s) ? $temp : (fmod($temp, 0x80000000) & 0x7FFFFFFF) | ';
+        return $safeint . '((fmod(floor($temp / 0x80000000), 2) & 1) << 31))';
+    }
+
+    /**
+     * Sets up GCM parameters
+     *
+     * See steps 1-2 of https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=23
+     * for more info
+     *
+     */
+    private function setupGCM()
+    {
+        // don't keep on re-calculating $this->h
+        if (!$this->h || $this->hKey != $this->key) {
+            $cipher = new static('ecb');
+            $cipher->setKey($this->key);
+            $cipher->disablePadding();
+
+            $this->h = self::$gcmField->newInteger(
+                Strings::switchEndianness($cipher->encrypt("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"))
+            );
+            $this->hKey = $this->key;
+        }
+
+        if (strlen($this->nonce) == 12) {
+            $this->iv = $this->nonce . "\0\0\0\1";
+        } else {
+            $this->iv = $this->ghash(
+                self::nullPad128($this->nonce) . str_repeat("\0", 8) . self::len64($this->nonce)
+            );
+        }
+    }
+
+    /**
+     * Performs GHASH operation
+     *
+     * See https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=20
+     * for more info
+     *
+     * @see self::decrypt()
+     * @see self::encrypt()
+     * @param string $x
+     * @return string
+     */
+    private function ghash($x)
+    {
+        $h = $this->h;
+        $y = ["\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"];
+        $x = str_split($x, 16);
+        $n = 0;
+        // the switchEndianness calls are necessary because the multiplication algorithm in BinaryField/Integer
+        // interprets strings as polynomials in big endian order whereas in GCM they're interpreted in little
+        // endian order per https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=19.
+        // big endian order is what binary field elliptic curves use per http://www.secg.org/sec1-v2.pdf#page=18.
+
+        // we could switchEndianness here instead of in the while loop but doing so in the while loop seems like it
+        // might be slightly more performant
+        //$x = Strings::switchEndianness($x);
+        foreach ($x as $xn) {
+            $xn = Strings::switchEndianness($xn);
+            $t = $y[$n] ^ $xn;
+            $temp = self::$gcmField->newInteger($t);
+            $y[++$n] = $temp->multiply($h)->toBytes();
+            $y[$n] = substr($y[$n], 1);
+        }
+        $y[$n] = Strings::switchEndianness($y[$n]);
+        return $y[$n];
+    }
+
+    /**
+     * Returns the bit length of a string in a packed format
+     *
+     * @see self::decrypt()
+     * @see self::encrypt()
+     * @see self::setupGCM()
+     * @param string $str
+     * @return string
+     */
+    private static function len64($str)
+    {
+        return "\0\0\0\0" . pack('N', 8 * strlen($str));
+    }
+
+    /**
+     * NULL pads a string to be a multiple of 128
+     *
+     * @see self::decrypt()
+     * @see self::encrypt()
+     * @see self::setupGCM()
+     * @param string $str
+     * @return string
+     */
+    protected static function nullPad128($str)
+    {
+        $len = strlen($str);
+        return $str . str_repeat("\0", 16 * ceil($len / 16) - $len);
+    }
+
+    /**
+     * Calculates Poly1305 MAC
+     *
+     * On my system ChaCha20, with libsodium, takes 0.5s. With this custom Poly1305 implementation
+     * it takes 1.2s.
+     *
+     * @see self::decrypt()
+     * @see self::encrypt()
+     * @param string $text
+     * @return string
+     */
+    protected function poly1305($text)
+    {
+        $s = $this->poly1305Key; // strlen($this->poly1305Key) == 32
+        $r = Strings::shift($s, 16);
+        $r = strrev($r);
+        $r &= "\x0f\xff\xff\xfc\x0f\xff\xff\xfc\x0f\xff\xff\xfc\x0f\xff\xff\xff";
+        $s = strrev($s);
+
+        $r = self::$poly1305Field->newInteger(new BigInteger($r, 256));
+        $s = self::$poly1305Field->newInteger(new BigInteger($s, 256));
+        $a = self::$poly1305Field->newInteger(new BigInteger());
+
+        $blocks = str_split($text, 16);
+        foreach ($blocks as $block) {
+            $n = strrev($block . chr(1));
+            $n = self::$poly1305Field->newInteger(new BigInteger($n, 256));
+            $a = $a->add($n);
+            $a = $a->multiply($r);
+        }
+        $r = $a->toBigInteger()->add($s->toBigInteger());
+        $mask = "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF";
+        return strrev($r->toBytes()) & $mask;
+    }
+
+    /**
+     * Return the mode
+     *
+     * You can do $obj instanceof AES or whatever to get the cipher but you can't do that to get the mode
+     *
+     * @return string
+     */
+    public function getMode()
+    {
+        return array_flip(self::MODE_MAP)[$this->mode];
+    }
+
+    /**
+     * Is the continuous buffer enabled?
+     *
+     * @return boolean
+     */
+    public function continuousBufferEnabled()
+    {
+        return $this->continuousBuffer;
+    }
+}