From f413647e91dd5f19fedfb3ef20aca614068d8781 Mon Sep 17 00:00:00 2001
From: shreesh arora <shreesh.arora608@webkul.com>
Date: Mon, 7 Feb 2022 10:50:16 +0530
Subject: [PATCH] resolve compatibility issue with php5.6

---
 config/autoload.php                           |   2 +
 tools/random_compat/LICENSE                   |  22 ++
 tools/random_compat/composer.json             |  38 +++
 tools/random_compat/dist/index.php            |  29 +++
 .../dist/random_compat.phar.pubkey            |   5 +
 .../dist/random_compat.phar.pubkey.asc        |  11 +
 tools/random_compat/index.php                 |  29 +++
 tools/random_compat/lib/byte_safe_strings.php | 195 +++++++++++++++
 tools/random_compat/lib/cast_to_int.php       |  77 ++++++
 tools/random_compat/lib/error_polyfill.php    |  49 ++++
 tools/random_compat/lib/index.php             |  29 +++
 tools/random_compat/lib/random.php            | 226 ++++++++++++++++++
 .../lib/random_bytes_com_dotnet.php           |  91 +++++++
 .../lib/random_bytes_dev_urandom.php          | 190 +++++++++++++++
 .../lib/random_bytes_libsodium.php            |  91 +++++++
 .../lib/random_bytes_libsodium_legacy.php     |  93 +++++++
 .../random_compat/lib/random_bytes_mcrypt.php |  79 ++++++
 tools/random_compat/lib/random_int.php        | 204 ++++++++++++++++
 18 files changed, 1460 insertions(+)
 create mode 100644 tools/random_compat/LICENSE
 create mode 100644 tools/random_compat/composer.json
 create mode 100644 tools/random_compat/dist/index.php
 create mode 100644 tools/random_compat/dist/random_compat.phar.pubkey
 create mode 100644 tools/random_compat/dist/random_compat.phar.pubkey.asc
 create mode 100644 tools/random_compat/index.php
 create mode 100644 tools/random_compat/lib/byte_safe_strings.php
 create mode 100644 tools/random_compat/lib/cast_to_int.php
 create mode 100644 tools/random_compat/lib/error_polyfill.php
 create mode 100644 tools/random_compat/lib/index.php
 create mode 100644 tools/random_compat/lib/random.php
 create mode 100644 tools/random_compat/lib/random_bytes_com_dotnet.php
 create mode 100644 tools/random_compat/lib/random_bytes_dev_urandom.php
 create mode 100644 tools/random_compat/lib/random_bytes_libsodium.php
 create mode 100644 tools/random_compat/lib/random_bytes_libsodium_legacy.php
 create mode 100644 tools/random_compat/lib/random_bytes_mcrypt.php
 create mode 100644 tools/random_compat/lib/random_int.php

diff --git a/config/autoload.php b/config/autoload.php
index 0cfc7a14c..c014a485b 100644
--- a/config/autoload.php
+++ b/config/autoload.php
@@ -24,6 +24,8 @@
 *  International Registered Trademark & Property of PrestaShop SA
 */
 require_once (_PS_TOOL_DIR_.'defuse/php-encryption/defuse-crypto.phar');
+require_once (_PS_TOOL_DIR_.'random_compat/lib/random.php');
+
 
 // Include some alias functions
 require_once(_PS_CONFIG_DIR_.'alias.php');
diff --git a/tools/random_compat/LICENSE b/tools/random_compat/LICENSE
new file mode 100644
index 000000000..45c7017df
--- /dev/null
+++ b/tools/random_compat/LICENSE
@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Paragon Initiative Enterprises
+
+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.
+
diff --git a/tools/random_compat/composer.json b/tools/random_compat/composer.json
new file mode 100644
index 000000000..34f1381d5
--- /dev/null
+++ b/tools/random_compat/composer.json
@@ -0,0 +1,38 @@
+{
+  "name":         "paragonie/random_compat",
+  "description":  "PHP 5.x polyfill for random_bytes() and random_int() from PHP 7",
+  "keywords": [
+    "csprng",
+    "random",
+    "polyfill",
+    "pseudorandom"
+  ],
+  "license":      "MIT",
+  "type":         "library",
+  "authors": [
+    {
+      "name":     "Paragon Initiative Enterprises",
+      "email":    "security@paragonie.com",
+      "homepage": "https://paragonie.com"
+    }
+  ],
+  "support": {
+    "issues":     "https://github.com/paragonie/random_compat/issues",
+    "email":      "info@paragonie.com",
+    "source":     "https://github.com/paragonie/random_compat"
+  },
+  "require": {
+    "php": ">=5.2.0"
+  },
+  "require-dev": {
+    "phpunit/phpunit": "4.*|5.*"
+  },
+  "suggest": {
+    "ext-libsodium": "Provides a modern crypto API that can be used to generate random bytes."
+  },
+  "autoload": {
+    "files": [
+      "lib/random.php"
+    ]
+  }
+}
diff --git a/tools/random_compat/dist/index.php b/tools/random_compat/dist/index.php
new file mode 100644
index 000000000..eaa1dc457
--- /dev/null
+++ b/tools/random_compat/dist/index.php
@@ -0,0 +1,29 @@
+<?php
+/**
+* 2010-2022 Webkul.
+*
+* NOTICE OF LICENSE
+*
+* All right is reserved,
+* Please go through this link for complete license : https://store.webkul.com/license.html
+*
+* DISCLAIMER
+*
+* Do not edit or add to this file if you wish to upgrade this module to newer
+* versions in the future. If you wish to customize this module for your
+* needs please refer to https://store.webkul.com/customisation-guidelines/ for more information.
+*
+*  @author    Webkul IN <support@webkul.com>
+*  @copyright 2010-2022 Webkul IN
+*  @license   https://store.webkul.com/license.html
+*/
+
+header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');
+header('Last-Modified: '.gmdate('D, d M Y H:i:s').' GMT');
+
+header('Cache-Control: no-store, no-cache, must-revalidate');
+header('Cache-Control: post-check=0, pre-check=0', false);
+header('Pragma: no-cache');
+
+header('Location: ../');
+exit;
diff --git a/tools/random_compat/dist/random_compat.phar.pubkey b/tools/random_compat/dist/random_compat.phar.pubkey
new file mode 100644
index 000000000..eb50ebfcd
--- /dev/null
+++ b/tools/random_compat/dist/random_compat.phar.pubkey
@@ -0,0 +1,5 @@
+-----BEGIN PUBLIC KEY-----
+MHYwEAYHKoZIzj0CAQYFK4EEACIDYgAEEd+wCqJDrx5B4OldM0dQE0ZMX+lx1ZWm
+pui0SUqD4G29L3NGsz9UhJ/0HjBdbnkhIK5xviT0X5vtjacF6ajgcCArbTB+ds+p
++h7Q084NuSuIpNb6YPfoUFgC/CL9kAoc
+-----END PUBLIC KEY-----
diff --git a/tools/random_compat/dist/random_compat.phar.pubkey.asc b/tools/random_compat/dist/random_compat.phar.pubkey.asc
new file mode 100644
index 000000000..6a1d7f300
--- /dev/null
+++ b/tools/random_compat/dist/random_compat.phar.pubkey.asc
@@ -0,0 +1,11 @@
+-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v2.0.22 (MingW32)
+
+iQEcBAABAgAGBQJWtW1hAAoJEGuXocKCZATaJf0H+wbZGgskK1dcRTsuVJl9IWip
+QwGw/qIKI280SD6/ckoUMxKDCJiFuPR14zmqnS36k7N5UNPnpdTJTS8T11jttSpg
+1LCmgpbEIpgaTah+cELDqFCav99fS+bEiAL5lWDAHBTE/XPjGVCqeehyPYref4IW
+NDBIEsvnHPHPLsn6X5jq4+Yj5oUixgxaMPiR+bcO4Sh+RzOVB6i2D0upWfRXBFXA
+NNnsg9/zjvoC7ZW73y9uSH+dPJTt/Vgfeiv52/v41XliyzbUyLalf02GNPY+9goV
+JHG1ulEEBJOCiUD9cE1PUIJwHA/HqyhHIvV350YoEFiHl8iSwm7SiZu5kPjaq74=
+=B6+8
+-----END PGP SIGNATURE-----
diff --git a/tools/random_compat/index.php b/tools/random_compat/index.php
new file mode 100644
index 000000000..eaa1dc457
--- /dev/null
+++ b/tools/random_compat/index.php
@@ -0,0 +1,29 @@
+<?php
+/**
+* 2010-2022 Webkul.
+*
+* NOTICE OF LICENSE
+*
+* All right is reserved,
+* Please go through this link for complete license : https://store.webkul.com/license.html
+*
+* DISCLAIMER
+*
+* Do not edit or add to this file if you wish to upgrade this module to newer
+* versions in the future. If you wish to customize this module for your
+* needs please refer to https://store.webkul.com/customisation-guidelines/ for more information.
+*
+*  @author    Webkul IN <support@webkul.com>
+*  @copyright 2010-2022 Webkul IN
+*  @license   https://store.webkul.com/license.html
+*/
+
+header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');
+header('Last-Modified: '.gmdate('D, d M Y H:i:s').' GMT');
+
+header('Cache-Control: no-store, no-cache, must-revalidate');
+header('Cache-Control: post-check=0, pre-check=0', false);
+header('Pragma: no-cache');
+
+header('Location: ../');
+exit;
diff --git a/tools/random_compat/lib/byte_safe_strings.php b/tools/random_compat/lib/byte_safe_strings.php
new file mode 100644
index 000000000..ef24488f9
--- /dev/null
+++ b/tools/random_compat/lib/byte_safe_strings.php
@@ -0,0 +1,195 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!is_callable('RandomCompat_strlen')) {
+    if (
+        defined('MB_OVERLOAD_STRING')
+            &&
+        ((int) ini_get('mbstring.func_overload')) & MB_OVERLOAD_STRING
+    ) {
+        /**
+         * strlen() implementation that isn't brittle to mbstring.func_overload
+         *
+         * This version uses mb_strlen() in '8bit' mode to treat strings as raw
+         * binary rather than UTF-8, ISO-8859-1, etc
+         *
+         * @param string $binary_string
+         *
+         * @throws TypeError
+         *
+         * @return int
+         */
+        function RandomCompat_strlen($binary_string)
+        {
+            if (!is_string($binary_string)) {
+                throw new TypeError(
+                    'RandomCompat_strlen() expects a string'
+                );
+            }
+
+            return (int) mb_strlen($binary_string, '8bit');
+        }
+
+    } else {
+        /**
+         * strlen() implementation that isn't brittle to mbstring.func_overload
+         *
+         * This version just used the default strlen()
+         *
+         * @param string $binary_string
+         *
+         * @throws TypeError
+         *
+         * @return int
+         */
+        function RandomCompat_strlen($binary_string)
+        {
+            if (!is_string($binary_string)) {
+                throw new TypeError(
+                    'RandomCompat_strlen() expects a string'
+                );
+            }
+            return (int) strlen($binary_string);
+        }
+    }
+}
+
+if (!is_callable('RandomCompat_substr')) {
+
+    if (
+        defined('MB_OVERLOAD_STRING')
+            &&
+        ((int) ini_get('mbstring.func_overload')) & MB_OVERLOAD_STRING
+    ) {
+        /**
+         * substr() implementation that isn't brittle to mbstring.func_overload
+         *
+         * This version uses mb_substr() in '8bit' mode to treat strings as raw
+         * binary rather than UTF-8, ISO-8859-1, etc
+         *
+         * @param string $binary_string
+         * @param int $start
+         * @param int|null $length (optional)
+         *
+         * @throws TypeError
+         *
+         * @return string
+         */
+        function RandomCompat_substr($binary_string, $start, $length = null)
+        {
+            if (!is_string($binary_string)) {
+                throw new TypeError(
+                    'RandomCompat_substr(): First argument should be a string'
+                );
+            }
+
+            if (!is_int($start)) {
+                throw new TypeError(
+                    'RandomCompat_substr(): Second argument should be an integer'
+                );
+            }
+
+            if ($length === null) {
+                /**
+                 * mb_substr($str, 0, NULL, '8bit') returns an empty string on
+                 * PHP 5.3, so we have to find the length ourselves.
+                 */
+                /** @var int $length */
+                $length = RandomCompat_strlen($binary_string) - $start;
+            } elseif (!is_int($length)) {
+                throw new TypeError(
+                    'RandomCompat_substr(): Third argument should be an integer, or omitted'
+                );
+            }
+
+            // Consistency with PHP's behavior
+            if ($start === RandomCompat_strlen($binary_string) && $length === 0) {
+                return '';
+            }
+            if ($start > RandomCompat_strlen($binary_string)) {
+                return '';
+            }
+
+            return (string) mb_substr(
+                (string) $binary_string,
+                (int) $start,
+                (int) $length,
+                '8bit'
+            );
+        }
+
+    } else {
+
+        /**
+         * substr() implementation that isn't brittle to mbstring.func_overload
+         *
+         * This version just uses the default substr()
+         *
+         * @param string $binary_string
+         * @param int $start
+         * @param int|null $length (optional)
+         *
+         * @throws TypeError
+         *
+         * @return string
+         */
+        function RandomCompat_substr($binary_string, $start, $length = null)
+        {
+            if (!is_string($binary_string)) {
+                throw new TypeError(
+                    'RandomCompat_substr(): First argument should be a string'
+                );
+            }
+
+            if (!is_int($start)) {
+                throw new TypeError(
+                    'RandomCompat_substr(): Second argument should be an integer'
+                );
+            }
+
+            if ($length !== null) {
+                if (!is_int($length)) {
+                    throw new TypeError(
+                        'RandomCompat_substr(): Third argument should be an integer, or omitted'
+                    );
+                }
+
+                return (string) substr(
+                    (string )$binary_string,
+                    (int) $start,
+                    (int) $length
+                );
+            }
+
+            return (string) substr(
+                (string) $binary_string,
+                (int) $start
+            );
+        }
+    }
+}
diff --git a/tools/random_compat/lib/cast_to_int.php b/tools/random_compat/lib/cast_to_int.php
new file mode 100644
index 000000000..1b1bbfe8d
--- /dev/null
+++ b/tools/random_compat/lib/cast_to_int.php
@@ -0,0 +1,77 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!is_callable('RandomCompat_intval')) {
+
+    /**
+     * Cast to an integer if we can, safely.
+     *
+     * If you pass it a float in the range (~PHP_INT_MAX, PHP_INT_MAX)
+     * (non-inclusive), it will sanely cast it to an int. If you it's equal to
+     * ~PHP_INT_MAX or PHP_INT_MAX, we let it fail as not an integer. Floats 
+     * lose precision, so the <= and => operators might accidentally let a float
+     * through.
+     *
+     * @param int|float $number    The number we want to convert to an int
+     * @param bool      $fail_open Set to true to not throw an exception
+     *
+     * @return float|int
+     * @psalm-suppress InvalidReturnType
+     *
+     * @throws TypeError
+     */
+    function RandomCompat_intval($number, $fail_open = false)
+    {
+        if (is_int($number) || is_float($number)) {
+            $number += 0;
+        } elseif (is_numeric($number)) {
+            /** @psalm-suppress InvalidOperand */
+            $number += 0;
+        }
+        /** @var int|float $number */
+
+        if (
+            is_float($number)
+                &&
+            $number > ~PHP_INT_MAX
+                &&
+            $number < PHP_INT_MAX
+        ) {
+            $number = (int) $number;
+        }
+
+        if (is_int($number)) {
+            return (int) $number;
+        } elseif (!$fail_open) {
+            throw new TypeError(
+                'Expected an integer.'
+            );
+        }
+        return $number;
+    }
+}
diff --git a/tools/random_compat/lib/error_polyfill.php b/tools/random_compat/lib/error_polyfill.php
new file mode 100644
index 000000000..c02c5c8b4
--- /dev/null
+++ b/tools/random_compat/lib/error_polyfill.php
@@ -0,0 +1,49 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!class_exists('Error', false)) {
+    // We can't really avoid making this extend Exception in PHP 5.
+    class Error extends Exception
+    {
+
+    }
+}
+
+if (!class_exists('TypeError', false)) {
+    if (is_subclass_of('Error', 'Exception')) {
+        class TypeError extends Error
+        {
+
+        }
+    } else {
+        class TypeError extends Exception
+        {
+
+        }
+    }
+}
diff --git a/tools/random_compat/lib/index.php b/tools/random_compat/lib/index.php
new file mode 100644
index 000000000..eaa1dc457
--- /dev/null
+++ b/tools/random_compat/lib/index.php
@@ -0,0 +1,29 @@
+<?php
+/**
+* 2010-2022 Webkul.
+*
+* NOTICE OF LICENSE
+*
+* All right is reserved,
+* Please go through this link for complete license : https://store.webkul.com/license.html
+*
+* DISCLAIMER
+*
+* Do not edit or add to this file if you wish to upgrade this module to newer
+* versions in the future. If you wish to customize this module for your
+* needs please refer to https://store.webkul.com/customisation-guidelines/ for more information.
+*
+*  @author    Webkul IN <support@webkul.com>
+*  @copyright 2010-2022 Webkul IN
+*  @license   https://store.webkul.com/license.html
+*/
+
+header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');
+header('Last-Modified: '.gmdate('D, d M Y H:i:s').' GMT');
+
+header('Cache-Control: no-store, no-cache, must-revalidate');
+header('Cache-Control: post-check=0, pre-check=0', false);
+header('Pragma: no-cache');
+
+header('Location: ../');
+exit;
diff --git a/tools/random_compat/lib/random.php b/tools/random_compat/lib/random.php
new file mode 100644
index 000000000..6df1cb0ce
--- /dev/null
+++ b/tools/random_compat/lib/random.php
@@ -0,0 +1,226 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * @version 2.0.17
+ * @released 2018-07-04
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!defined('PHP_VERSION_ID')) {
+    // This constant was introduced in PHP 5.2.7
+    $RandomCompatversion = array_map('intval', explode('.', PHP_VERSION));
+    define(
+        'PHP_VERSION_ID',
+        $RandomCompatversion[0] * 10000
+        + $RandomCompatversion[1] * 100
+        + $RandomCompatversion[2]
+    );
+    $RandomCompatversion = null;
+}
+
+/**
+ * PHP 7.0.0 and newer have these functions natively.
+ */
+if (PHP_VERSION_ID >= 70000) {
+    return;
+}
+
+if (!defined('RANDOM_COMPAT_READ_BUFFER')) {
+    define('RANDOM_COMPAT_READ_BUFFER', 8);
+}
+
+$RandomCompatDIR = dirname(__FILE__);
+
+require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'byte_safe_strings.php';
+require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'cast_to_int.php';
+require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'error_polyfill.php';
+
+if (!is_callable('random_bytes')) {
+    /**
+     * PHP 5.2.0 - 5.6.x way to implement random_bytes()
+     *
+     * We use conditional statements here to define the function in accordance
+     * to the operating environment. It's a micro-optimization.
+     *
+     * In order of preference:
+     *   1. Use libsodium if available.
+     *   2. fread() /dev/urandom if available (never on Windows)
+     *   3. mcrypt_create_iv($bytes, MCRYPT_DEV_URANDOM)
+     *   4. COM('CAPICOM.Utilities.1')->GetRandom()
+     *
+     * See RATIONALE.md for our reasoning behind this particular order
+     */
+    if (extension_loaded('libsodium')) {
+        // See random_bytes_libsodium.php
+        if (PHP_VERSION_ID >= 50300 && is_callable('\\Sodium\\randombytes_buf')) {
+            require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'random_bytes_libsodium.php';
+        } elseif (method_exists('Sodium', 'randombytes_buf')) {
+            require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'random_bytes_libsodium_legacy.php';
+        }
+    }
+
+    /**
+     * Reading directly from /dev/urandom:
+     */
+    if (DIRECTORY_SEPARATOR === '/') {
+        // DIRECTORY_SEPARATOR === '/' on Unix-like OSes -- this is a fast
+        // way to exclude Windows.
+        $RandomCompatUrandom = true;
+        $RandomCompat_basedir = ini_get('open_basedir');
+
+        if (!empty($RandomCompat_basedir)) {
+            $RandomCompat_open_basedir = explode(
+                PATH_SEPARATOR,
+                strtolower($RandomCompat_basedir)
+            );
+            $RandomCompatUrandom = (array() !== array_intersect(
+                array('/dev', '/dev/', '/dev/urandom'),
+                $RandomCompat_open_basedir
+            ));
+            $RandomCompat_open_basedir = null;
+        }
+
+        if (
+            !is_callable('random_bytes')
+            &&
+            $RandomCompatUrandom
+            &&
+            @is_readable('/dev/urandom')
+        ) {
+            // Error suppression on is_readable() in case of an open_basedir
+            // or safe_mode failure. All we care about is whether or not we
+            // can read it at this point. If the PHP environment is going to
+            // panic over trying to see if the file can be read in the first
+            // place, that is not helpful to us here.
+
+            // See random_bytes_dev_urandom.php
+            require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'random_bytes_dev_urandom.php';
+        }
+        // Unset variables after use
+        $RandomCompat_basedir = null;
+    } else {
+        $RandomCompatUrandom = false;
+    }
+
+    /**
+     * mcrypt_create_iv()
+     *
+     * We only want to use mcypt_create_iv() if:
+     *
+     * - random_bytes() hasn't already been defined
+     * - the mcrypt extensions is loaded
+     * - One of these two conditions is true:
+     *   - We're on Windows (DIRECTORY_SEPARATOR !== '/')
+     *   - We're not on Windows and /dev/urandom is readabale
+     *     (i.e. we're not in a chroot jail)
+     * - Special case:
+     *   - If we're not on Windows, but the PHP version is between
+     *     5.6.10 and 5.6.12, we don't want to use mcrypt. It will
+     *     hang indefinitely. This is bad.
+     *   - If we're on Windows, we want to use PHP >= 5.3.7 or else
+     *     we get insufficient entropy errors.
+     */
+    if (
+        !is_callable('random_bytes')
+        &&
+        // Windows on PHP < 5.3.7 is broken, but non-Windows is not known to be.
+        (DIRECTORY_SEPARATOR === '/' || PHP_VERSION_ID >= 50307)
+        &&
+        // Prevent this code from hanging indefinitely on non-Windows;
+        // see https://bugs.php.net/bug.php?id=69833
+        (
+            DIRECTORY_SEPARATOR !== '/' ||
+            (PHP_VERSION_ID <= 50609 || PHP_VERSION_ID >= 50613)
+        )
+        &&
+        extension_loaded('mcrypt')
+    ) {
+        // See random_bytes_mcrypt.php
+        require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'random_bytes_mcrypt.php';
+    }
+    $RandomCompatUrandom = null;
+
+    /**
+     * This is a Windows-specific fallback, for when the mcrypt extension
+     * isn't loaded.
+     */
+    if (
+        !is_callable('random_bytes')
+        &&
+        extension_loaded('com_dotnet')
+        &&
+        class_exists('COM')
+    ) {
+        $RandomCompat_disabled_classes = preg_split(
+            '#\s*,\s*#',
+            strtolower(ini_get('disable_classes'))
+        );
+
+        if (!in_array('com', $RandomCompat_disabled_classes)) {
+            try {
+                $RandomCompatCOMtest = new COM('CAPICOM.Utilities.1');
+                /** @psalm-suppress TypeDoesNotContainType */
+                if (method_exists($RandomCompatCOMtest, 'GetRandom')) {
+                    // See random_bytes_com_dotnet.php
+                    require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'random_bytes_com_dotnet.php';
+                }
+            } catch (com_exception $e) {
+                // Don't try to use it.
+            }
+        }
+        $RandomCompat_disabled_classes = null;
+        $RandomCompatCOMtest = null;
+    }
+
+    /**
+     * throw new Exception
+     */
+    if (!is_callable('random_bytes')) {
+        /**
+         * We don't have any more options, so let's throw an exception right now
+         * and hope the developer won't let it fail silently.
+         *
+         * @param mixed $length
+         * @psalm-suppress InvalidReturnType
+         * @throws Exception
+         * @return string
+         */
+        function random_bytes($length)
+        {
+            unset($length); // Suppress "variable not used" warnings.
+            throw new Exception(
+                'There is no suitable CSPRNG installed on your system'
+            );
+            return '';
+        }
+    }
+}
+
+if (!is_callable('random_int')) {
+    require_once $RandomCompatDIR.DIRECTORY_SEPARATOR.'random_int.php';
+}
+
+$RandomCompatDIR = null;
diff --git a/tools/random_compat/lib/random_bytes_com_dotnet.php b/tools/random_compat/lib/random_bytes_com_dotnet.php
new file mode 100644
index 000000000..537d02b27
--- /dev/null
+++ b/tools/random_compat/lib/random_bytes_com_dotnet.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!is_callable('random_bytes')) {
+    /**
+     * Windows with PHP < 5.3.0 will not have the function
+     * openssl_random_pseudo_bytes() available, so let's use
+     * CAPICOM to work around this deficiency.
+     *
+     * @param int $bytes
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    function random_bytes($bytes)
+    {
+        try {
+            /** @var int $bytes */
+            $bytes = RandomCompat_intval($bytes);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_bytes(): $bytes must be an integer'
+            );
+        }
+
+        if ($bytes < 1) {
+            throw new Error(
+                'Length must be greater than 0'
+            );
+        }
+
+        /** @var string $buf */
+        $buf = '';
+        if (!class_exists('COM')) {
+            throw new Error(
+                'COM does not exist'
+            );
+        }
+        /** @var COM $util */
+        $util = new COM('CAPICOM.Utilities.1');
+        $execCount = 0;
+
+        /**
+         * Let's not let it loop forever. If we run N times and fail to
+         * get N bytes of random data, then CAPICOM has failed us.
+         */
+        do {
+            $buf .= base64_decode((string) $util->GetRandom($bytes, 0));
+            if (RandomCompat_strlen($buf) >= $bytes) {
+                /**
+                 * Return our random entropy buffer here:
+                 */
+                return (string) RandomCompat_substr($buf, 0, $bytes);
+            }
+            ++$execCount;
+        } while ($execCount < $bytes);
+
+        /**
+         * If we reach here, PHP has failed us.
+         */
+        throw new Exception(
+            'Could not gather sufficient random data'
+        );
+    }
+}
diff --git a/tools/random_compat/lib/random_bytes_dev_urandom.php b/tools/random_compat/lib/random_bytes_dev_urandom.php
new file mode 100644
index 000000000..c4e31ccbb
--- /dev/null
+++ b/tools/random_compat/lib/random_bytes_dev_urandom.php
@@ -0,0 +1,190 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!defined('RANDOM_COMPAT_READ_BUFFER')) {
+    define('RANDOM_COMPAT_READ_BUFFER', 8);
+}
+
+if (!is_callable('random_bytes')) {
+    /**
+     * Unless open_basedir is enabled, use /dev/urandom for
+     * random numbers in accordance with best practices
+     *
+     * Why we use /dev/urandom and not /dev/random
+     * @ref https://www.2uo.de/myths-about-urandom
+     * @ref http://sockpuppet.org/blog/2014/02/25/safely-generate-random-numbers
+     *
+     * @param int $bytes
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    function random_bytes($bytes)
+    {
+        /** @var resource $fp */
+        static $fp = null;
+
+        /**
+         * This block should only be run once
+         */
+        if (empty($fp)) {
+            /**
+             * We don't want to ever read C:\dev\random, only /dev/urandom on
+             * Unix-like operating systems. While we guard against this
+             * condition in random.php, it doesn't hurt to be defensive in depth
+             * here.
+             *
+             * To that end, we only try to open /dev/urandom if we're on a Unix-
+             * like operating system (which means the directory separator is set
+             * to "/" not "\".
+             */
+            if (DIRECTORY_SEPARATOR === '/') {
+                if (!is_readable('/dev/urandom')) {
+                    throw new Exception(
+                        'Environment misconfiguration: ' .
+                        '/dev/urandom cannot be read.'
+                    );
+                }
+                /**
+                 * We use /dev/urandom if it is a char device.
+                 * We never fall back to /dev/random
+                 */
+                /** @var resource|bool $fp */
+                $fp = fopen('/dev/urandom', 'rb');
+                if (is_resource($fp)) {
+                    /** @var array<string, int> $st */
+                    $st = fstat($fp);
+                    if (($st['mode'] & 0170000) !== 020000) {
+                        fclose($fp);
+                        $fp = false;
+                    }
+                }
+            }
+
+            if (is_resource($fp)) {
+                /**
+                 * stream_set_read_buffer() does not exist in HHVM
+                 *
+                 * If we don't set the stream's read buffer to 0, PHP will
+                 * internally buffer 8192 bytes, which can waste entropy
+                 *
+                 * stream_set_read_buffer returns 0 on success
+                 */
+                if (is_callable('stream_set_read_buffer')) {
+                    stream_set_read_buffer($fp, RANDOM_COMPAT_READ_BUFFER);
+                }
+                if (is_callable('stream_set_chunk_size')) {
+                    stream_set_chunk_size($fp, RANDOM_COMPAT_READ_BUFFER);
+                }
+            }
+        }
+
+        try {
+            /** @var int $bytes */
+            $bytes = RandomCompat_intval($bytes);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_bytes(): $bytes must be an integer'
+            );
+        }
+
+        if ($bytes < 1) {
+            throw new Error(
+                'Length must be greater than 0'
+            );
+        }
+
+        /**
+         * This if() block only runs if we managed to open a file handle
+         *
+         * It does not belong in an else {} block, because the above
+         * if (empty($fp)) line is logic that should only be run once per
+         * page load.
+         */
+        if (is_resource($fp)) {
+            /**
+             * @var int
+             */
+            $remaining = $bytes;
+
+            /**
+             * @var string|bool
+             */
+            $buf = '';
+
+            /**
+             * We use fread() in a loop to protect against partial reads
+             */
+            do {
+                /**
+                 * @var string|bool
+                 */
+                $read = fread($fp, $remaining);
+                if (!is_string($read)) {
+                    /**
+                     * We cannot safely read from the file. Exit the
+                     * do-while loop and trigger the exception condition
+                     *
+                     * @var string|bool
+                     */
+                    $buf = false;
+                    break;
+                }
+                /**
+                 * Decrease the number of bytes returned from remaining
+                 */
+                $remaining -= RandomCompat_strlen($read);
+                /**
+                 * @var string $buf
+                 */
+                $buf .= $read;
+            } while ($remaining > 0);
+
+            /**
+             * Is our result valid?
+             * @var string|bool $buf
+             */
+            if (is_string($buf)) {
+                if (RandomCompat_strlen($buf) === $bytes) {
+                    /**
+                     * Return our random entropy buffer here:
+                     */
+                    return $buf;
+                }
+            }
+        }
+
+        /**
+         * If we reach here, PHP has failed us.
+         */
+        throw new Exception(
+            'Error reading from source device'
+        );
+    }
+}
diff --git a/tools/random_compat/lib/random_bytes_libsodium.php b/tools/random_compat/lib/random_bytes_libsodium.php
new file mode 100644
index 000000000..2e5629018
--- /dev/null
+++ b/tools/random_compat/lib/random_bytes_libsodium.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!is_callable('random_bytes')) {
+    /**
+     * If the libsodium PHP extension is loaded, we'll use it above any other
+     * solution.
+     *
+     * libsodium-php project:
+     * @ref https://github.com/jedisct1/libsodium-php
+     *
+     * @param int $bytes
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    function random_bytes($bytes)
+    {
+        try {
+            /** @var int $bytes */
+            $bytes = RandomCompat_intval($bytes);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_bytes(): $bytes must be an integer'
+            );
+        }
+
+        if ($bytes < 1) {
+            throw new Error(
+                'Length must be greater than 0'
+            );
+        }
+
+        /**
+         * \Sodium\randombytes_buf() doesn't allow more than 2147483647 bytes to be
+         * generated in one invocation.
+         */
+        /** @var string|bool $buf */
+        if ($bytes > 2147483647) {
+            $buf = '';
+            for ($i = 0; $i < $bytes; $i += 1073741824) {
+                $n = ($bytes - $i) > 1073741824
+                    ? 1073741824
+                    : $bytes - $i;
+                $buf .= \Sodium\randombytes_buf($n);
+            }
+        } else {
+            /** @var string|bool $buf */
+            $buf = \Sodium\randombytes_buf($bytes);
+        }
+
+        if (is_string($buf)) {
+            if (RandomCompat_strlen($buf) === $bytes) {
+                return $buf;
+            }
+        }
+
+        /**
+         * If we reach here, PHP has failed us.
+         */
+        throw new Exception(
+            'Could not gather sufficient random data'
+        );
+    }
+}
diff --git a/tools/random_compat/lib/random_bytes_libsodium_legacy.php b/tools/random_compat/lib/random_bytes_libsodium_legacy.php
new file mode 100644
index 000000000..f78b2199a
--- /dev/null
+++ b/tools/random_compat/lib/random_bytes_libsodium_legacy.php
@@ -0,0 +1,93 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!is_callable('random_bytes')) {
+    /**
+     * If the libsodium PHP extension is loaded, we'll use it above any other
+     * solution.
+     *
+     * libsodium-php project:
+     * @ref https://github.com/jedisct1/libsodium-php
+     *
+     * @param int $bytes
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    function random_bytes($bytes)
+    {
+        try {
+            /** @var int $bytes */
+            $bytes = RandomCompat_intval($bytes);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_bytes(): $bytes must be an integer'
+            );
+        }
+
+        if ($bytes < 1) {
+            throw new Error(
+                'Length must be greater than 0'
+            );
+        }
+
+        /**
+         * @var string
+         */
+        $buf = '';
+
+        /**
+         * \Sodium\randombytes_buf() doesn't allow more than 2147483647 bytes to be
+         * generated in one invocation.
+         */
+        if ($bytes > 2147483647) {
+            for ($i = 0; $i < $bytes; $i += 1073741824) {
+                $n = ($bytes - $i) > 1073741824
+                    ? 1073741824
+                    : $bytes - $i;
+                $buf .= Sodium::randombytes_buf((int) $n);
+            }
+        } else {
+            $buf .= Sodium::randombytes_buf((int) $bytes);
+        }
+
+        if (is_string($buf)) {
+            if (RandomCompat_strlen($buf) === $bytes) {
+                return $buf;
+            }
+        }
+
+        /**
+         * If we reach here, PHP has failed us.
+         */
+        throw new Exception(
+            'Could not gather sufficient random data'
+        );
+    }
+}
diff --git a/tools/random_compat/lib/random_bytes_mcrypt.php b/tools/random_compat/lib/random_bytes_mcrypt.php
new file mode 100644
index 000000000..0b13fa73c
--- /dev/null
+++ b/tools/random_compat/lib/random_bytes_mcrypt.php
@@ -0,0 +1,79 @@
+<?php
+/**
+ * Random_* Compatibility Library
+ * for using the new PHP 7 random_* API in PHP 5 projects
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+ *
+ * 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.
+ */
+
+if (!is_callable('random_bytes')) {
+    /**
+     * Powered by ext/mcrypt (and thankfully NOT libmcrypt)
+     *
+     * @ref https://bugs.php.net/bug.php?id=55169
+     * @ref https://github.com/php/php-src/blob/c568ffe5171d942161fc8dda066bce844bdef676/ext/mcrypt/mcrypt.c#L1321-L1386
+     *
+     * @param int $bytes
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    function random_bytes($bytes)
+    {
+        try {
+            /** @var int $bytes */
+            $bytes = RandomCompat_intval($bytes);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_bytes(): $bytes must be an integer'
+            );
+        }
+
+        if ($bytes < 1) {
+            throw new Error(
+                'Length must be greater than 0'
+            );
+        }
+
+        /** @var string|bool $buf */
+        $buf = @mcrypt_create_iv((int) $bytes, (int) MCRYPT_DEV_URANDOM);
+        if (
+            is_string($buf)
+                &&
+            RandomCompat_strlen($buf) === $bytes
+        ) {
+            /**
+             * Return our random entropy buffer here:
+             */
+            return $buf;
+        }
+
+        /**
+         * If we reach here, PHP has failed us.
+         */
+        throw new Exception(
+            'Could not gather sufficient random data'
+        );
+    }
+}
diff --git a/tools/random_compat/lib/random_int.php b/tools/random_compat/lib/random_int.php
new file mode 100644
index 000000000..ff80dfa43
--- /dev/null
+++ b/tools/random_compat/lib/random_int.php
@@ -0,0 +1,204 @@
+<?php
+
+if (!is_callable('random_int')) {
+    /**
+     * Random_* Compatibility Library
+     * for using the new PHP 7 random_* API in PHP 5 projects
+     *
+     * The MIT License (MIT)
+     *
+     * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
+     *
+     * 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.
+     */
+
+    /**
+     * Fetch a random integer between $min and $max inclusive
+     *
+     * @param int $min
+     * @param int $max
+     *
+     * @throws Exception
+     *
+     * @return int
+     */
+    function random_int($min, $max)
+    {
+        /**
+         * Type and input logic checks
+         *
+         * If you pass it a float in the range (~PHP_INT_MAX, PHP_INT_MAX)
+         * (non-inclusive), it will sanely cast it to an int. If you it's equal to
+         * ~PHP_INT_MAX or PHP_INT_MAX, we let it fail as not an integer. Floats
+         * lose precision, so the <= and => operators might accidentally let a float
+         * through.
+         */
+
+        try {
+            /** @var int $min */
+            $min = RandomCompat_intval($min);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_int(): $min must be an integer'
+            );
+        }
+
+        try {
+            /** @var int $max */
+            $max = RandomCompat_intval($max);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_int(): $max must be an integer'
+            );
+        }
+
+        /**
+         * Now that we've verified our weak typing system has given us an integer,
+         * let's validate the logic then we can move forward with generating random
+         * integers along a given range.
+         */
+        if ($min > $max) {
+            throw new Error(
+                'Minimum value must be less than or equal to the maximum value'
+            );
+        }
+
+        if ($max === $min) {
+            return (int) $min;
+        }
+
+        /**
+         * Initialize variables to 0
+         *
+         * We want to store:
+         * $bytes => the number of random bytes we need
+         * $mask => an integer bitmask (for use with the &) operator
+         *          so we can minimize the number of discards
+         */
+        $attempts = $bits = $bytes = $mask = $valueShift = 0;
+        /** @var int $attempts */
+        /** @var int $bits */
+        /** @var int $bytes */
+        /** @var int $mask */
+        /** @var int $valueShift */
+
+        /**
+         * At this point, $range is a positive number greater than 0. It might
+         * overflow, however, if $max - $min > PHP_INT_MAX. PHP will cast it to
+         * a float and we will lose some precision.
+         *
+         * @var int|float $range
+         */
+        $range = $max - $min;
+
+        /**
+         * Test for integer overflow:
+         */
+        if (!is_int($range)) {
+
+            /**
+             * Still safely calculate wider ranges.
+             * Provided by @CodesInChaos, @oittaa
+             *
+             * @ref https://gist.github.com/CodesInChaos/03f9ea0b58e8b2b8d435
+             *
+             * We use ~0 as a mask in this case because it generates all 1s
+             *
+             * @ref https://eval.in/400356 (32-bit)
+             * @ref http://3v4l.org/XX9r5  (64-bit)
+             */
+            $bytes = PHP_INT_SIZE;
+            /** @var int $mask */
+            $mask = ~0;
+
+        } else {
+
+            /**
+             * $bits is effectively ceil(log($range, 2)) without dealing with
+             * type juggling
+             */
+            while ($range > 0) {
+                if ($bits % 8 === 0) {
+                    ++$bytes;
+                }
+                ++$bits;
+                $range >>= 1;
+                /** @var int $mask */
+                $mask = $mask << 1 | 1;
+            }
+            $valueShift = $min;
+        }
+
+        /** @var int $val */
+        $val = 0;
+        /**
+         * Now that we have our parameters set up, let's begin generating
+         * random integers until one falls between $min and $max
+         */
+        /** @psalm-suppress RedundantCondition */
+        do {
+            /**
+             * The rejection probability is at most 0.5, so this corresponds
+             * to a failure probability of 2^-128 for a working RNG
+             */
+            if ($attempts > 128) {
+                throw new Exception(
+                    'random_int: RNG is broken - too many rejections'
+                );
+            }
+
+            /**
+             * Let's grab the necessary number of random bytes
+             */
+            $randomByteString = random_bytes($bytes);
+
+            /**
+             * Let's turn $randomByteString into an integer
+             *
+             * This uses bitwise operators (<< and |) to build an integer
+             * out of the values extracted from ord()
+             *
+             * Example: [9F] | [6D] | [32] | [0C] =>
+             *   159 + 27904 + 3276800 + 201326592 =>
+             *   204631455
+             */
+            $val &= 0;
+            for ($i = 0; $i < $bytes; ++$i) {
+                $val |= ord($randomByteString[$i]) << ($i * 8);
+            }
+            /** @var int $val */
+
+            /**
+             * Apply mask
+             */
+            $val &= $mask;
+            $val += $valueShift;
+
+            ++$attempts;
+            /**
+             * If $val overflows to a floating point number,
+             * ... or is larger than $max,
+             * ... or smaller than $min,
+             * then try again.
+             */
+        } while (!is_int($val) || $val > $max || $val < $min);
+
+        return (int) $val;
+    }
+}