If we're rocking PHP 7, this library should be a NOP

paragonie · Sep 7, 2015 · 90da7f3 · 90da7f3
1 parent 59e7857
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diff --git a/ERRATA.md b/ERRATA.md
@@ -9,9 +9,8 @@ The order is:
  3. `COM('CAPICOM.Utilities.1')->GetRandom()`
  4. `openssl_random_pseudo_bytes()`
 
-We read `/dev/urandom` first (if it exists).
-This is the preferred file to read for random data for cryptographic
-purposes for BSD and Linux.
+We read `/dev/urandom` first (if it exists). This is the preferred file to read
+for random data for cryptographic purposes for BSD and Linux.
 
 Despite [strongly urging people not to use mcrypt in their projects](https://paragonie.com/blog/2015/05/if-you-re-typing-word-mcrypt-into-your-code-you-re-doing-it-wrong),
 because libmcrypt is abandonware and the API puts too much responsibility on the
@@ -28,8 +27,9 @@ and is not part `libmcrypt`. It actually does the right thing:
 
 If we're on Windows and don't have access to `mcrypt`, we use `CAPICOM.Utilities.1`.
 
-Finally, we use `openssl_random_pseudo_bytes()` **as a last resort**. Internally,
-this function calls `RAND_pseudo_bytes()`, which has been [deprecated](https://github.com/paragonie/random_compat/issues/5)
+Finally, we use `openssl_random_pseudo_bytes()` **as a last resort**, due to
+[PHP bug #70014](https://bugs.php.net/bug.php?id=70014). Internally, this 
+function calls `RAND_pseudo_bytes()`, which has been [deprecated](https://github.com/paragonie/random_compat/issues/5)
 by the OpenSSL team. Furthermore, [it might silently return weak random data](https://github.com/paragonie/random_compat/issues/6#issuecomment-119564973)
 if it is called before OpenSSL's **userspace** CSPRNG is seeded. Also, 
-[you want the OS CSPRNG, not a userspace CSPRNG](http://sockpuppet.org/blog/2014/02/25/safely-generate-random-numbers/).
+[you want the OS CSPRNG, not a userspace CSPRNG](http://sockpuppet.org/blog/2014/02/25/safely-generate-random-numbers/).
diff --git a/lib/error_polyfill.php b/lib/error_polyfill.php
@@ -30,10 +30,18 @@
     interface Throwable
     {
         public function getMessage();
+        public function getCode();
+        public function getFile();
+        public function getLine();
+        public function getTrace();
+        public function getTraceAsString();
+        public function getPrevious();
+        public function __toString();
     }
 }
 
 if (!class_exists('Error', false)) {
+    // We can't really avoid making this extend Exception in PHP 5.
     class Error extends Exception implements Throwable
     {
 

diff --git a/lib/random.php b/lib/random.php
@@ -26,55 +26,55 @@
  * SOFTWARE.
  */
 
-if (!defined('RANDOM_COMPAT_READ_BUFFER')) {
-    define('RANDOM_COMPAT_READ_BUFFER', 8);
-}
 if (!defined('PHP_VERSION_ID')) {
+    // This constant was introduced in PHP 5.2.7
     $version = explode('.', PHP_VERSION);
     define('PHP_VERSION_ID', ($version[0] * 10000 + $version[1] * 100 + $version[2]));
 }
-
-require_once "error_polyfill.php";
-require_once "byte_safe_strings.php";
-
-if (!function_exists('random_bytes')) {
-    /**
-     * PHP 5.2.0 - 5.6.x way to implement random_bytes()
-     * 
-     * We use conditional statements here to define the function in accordance
-     * to the operating environment. It's a micro-optimization.
-     * 
-     * In order of preference:
-     *   1. fread() /dev/urandom if available
-     *   2. mcrypt_create_iv($bytes, MCRYPT_CREATE_IV)
-     *   3. COM('CAPICOM.Utilities.1')->GetRandom()
-     *   4. openssl_random_pseudo_bytes()
-     * 
-     * See ERRATA.md for our reasoning behind this particular order
-     */
-     if (!ini_get('open_basedir') && is_readable('/dev/urandom')) {
-        // See random_bytes_dev_urandom.php
-        require_once "random_bytes_dev_urandom.php";
-    } elseif (PHP_VERSION_ID >= 50307 && function_exists('mcrypt_create_iv')) {
-        // See random_bytes_mcrypt.php
-        require_once "random_bytes_mcrypt.php";
-    } elseif (extension_loaded('com_dotnet')) {
-        // See random_bytes_com_dotnet.php
-        require_once "random_bytes_com_dotnet.php";
-    } elseif (function_exists('openssl_random_pseudo_bytes')) {
-        // See random_bytes_openssl.php
-        require_once "random_bytes_openssl.php";
-    } else {
+if (PHP_VERSION_ID < 70000) {
+    if (!defined('RANDOM_COMPAT_READ_BUFFER')) {
+        define('RANDOM_COMPAT_READ_BUFFER', 8);
+    }
+    require_once "byte_safe_strings.php";
+    require_once "error_polyfill.php";
+    if (!function_exists('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.
+         * 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. fread() /dev/urandom if available
+         *   2. mcrypt_create_iv($bytes, MCRYPT_CREATE_IV)
+         *   3. COM('CAPICOM.Utilities.1')->GetRandom()
+         *   4. openssl_random_pseudo_bytes()
+         * 
+         * See ERRATA.md for our reasoning behind this particular order
          */
-        throw new Exception(
-            'There is no suitable CSPRNG installed on your system'
-        );
+         if (!ini_get('open_basedir') && is_readable('/dev/urandom')) {
+            // See random_bytes_dev_urandom.php
+            require_once "random_bytes_dev_urandom.php";
+        } elseif (PHP_VERSION_ID >= 50307 && function_exists('mcrypt_create_iv')) {
+            // See random_bytes_mcrypt.php
+            require_once "random_bytes_mcrypt.php";
+        } elseif (extension_loaded('com_dotnet')) {
+            // See random_bytes_com_dotnet.php
+            require_once "random_bytes_com_dotnet.php";
+        } elseif (function_exists('openssl_random_pseudo_bytes')) {
+            // See random_bytes_openssl.php
+            require_once "random_bytes_openssl.php";
+        } else {
+            /**
+             * 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.
+             */
+            throw new Exception(
+                'There is no suitable CSPRNG installed on your system'
+            );
+        }
+    }
+    if (!function_exists('random_int')) {
+        require_once "random_int.php";
     }
 }
-if (!function_exists('random_int')) {
-    require_once "random_int.php";
-}
-