Merge 14afeac into 296cd31

rchouinard · Jan 10, 2019 · ac793ba · ac793ba
2 parents 296cd31 + 14afeac
commit ac793ba
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diff --git a/src/Generator/CSPRNGenerator.php b/src/Generator/CSPRNGenerator.php
@@ -0,0 +1,76 @@
+<?php
+/**
+ * Ryan's Random Data Library
+ *
+ * @package Rych\Random
+ * @author Ryan Chouinard <rchouinard@gmail.com>
+ * @copyright Copyright (c) 2013, Ryan Chouinard
+ * @license MIT License - http://www.opensource.org/licenses/mit-license.php
+ */
+
+namespace Rych\Random\Generator;
+
+/**
+ * Cryptographically secure pseudo-random number generator
+ *
+ * The cryptographically secure pseudo-random number generator (CSPRNG) API
+ * provides an easy and reliable way to generate crypto-strong random integers
+ * and bytes for use within cryptographic contexts.
+ *
+ * @package Rych\Random
+ * @author Ryan Chouinard <rchouinard@gmail.com>
+ * @copyright Copyright (c) 2013, Ryan Chouinard
+ * @license MIT License - http://www.opensource.org/licenses/mit-license.php
+ */
+class CSPRNGenerator implements GeneratorInterface
+{
+
+    /**
+     * Generate a string of random data.
+     *
+     * @param  integer $byteCount The desired number of bytes.
+     * @return string  Returns the generated string.
+     */
+    public function generate($byteCount)
+    {
+      $bytes = '';
+
+      if (self::isSupported()) {
+        $mcryptStr = random_bytes($byteCount);
+        if ($mcryptStr !== false) {
+          $bytes = $mcryptStr;
+        }
+      }
+
+      return str_pad($bytes, $byteCount, chr(0));
+    }
+
+    /**
+     * Test system support for this generator.
+     *
+     * @return boolean Returns true if the generator is supported on the current
+     *     platform, otherwise false.
+     */
+    public static function isSupported()
+    {
+      $supported = false;
+      if (function_exists('random_bytes') &&
+        version_compare(phpversion(), '7.1', '>=')) {
+        $supported = true;
+      }
+
+      return $supported;
+    }
+
+    /**
+     * Get the generator priority.
+     *
+     * @return integer Returns an integer indicating the priority of the
+     *     generator. Lower numbers represent lower priorities.
+     */
+    public static function getPriority()
+    {
+        return GeneratorInterface::PRIORITY_HIGH;
+    }
+
+}
diff --git a/tests/Generator/CSPRNGeneratorTest.php b/tests/Generator/CSPRNGeneratorTest.php
@@ -0,0 +1,64 @@
+<?php
+/**
+ * Ryan's Random Data Library
+ *
+ * @package Rych\Random
+ * @author Ryan Chouinard <rchouinard@gmail.com>
+ * @copyright Copyright (c) 2013, Ryan Chouinard
+ * @license MIT License - http://www.opensource.org/licenses/mit-license.php
+ */
+
+namespace Rych\Random\Tests\Generator;
+
+use Rych\Random\Generator\CSPRNGenerator;
+use PHPUnit_Framework_TestCase as TestCase;
+
+/**
+ * CSPRN generator tests
+ *
+ * @package Rych\Random
+ * @author Ryan Chouinard <rchouinard@gmail.com>
+ * @copyright Copyright (c) 2013, Ryan Chouinard
+ * @license MIT License - http://www.opensource.org/licenses/mit-license.php
+ */
+class CSPRNGeneratorTest extends TestCase
+{
+
+    /**
+     * @return void
+     */
+    protected function setUp()
+    {
+        if (!CSPRNGenerator::isSupported()) {
+            $this->markTestSkipped('CSPRNG is not supported on this platform.');
+        }
+    }
+
+    /**
+     * @test
+     * @return void
+     */
+    public function testGenerateMethodProducesVaryingResultsEachCall()
+    {
+        $generator = new CSPRNGenerator;
+        $previous = array ();
+        for ($i = 0; $i < 10; ++$i) {
+            $result = $generator->generate(8);
+            $this->assertTrue(strlen($result) === 8, 'Generator should produce a string length of eight.');
+            $this->assertFalse(in_array($result, $previous), 'Generator should not duplicate a previous result in subsequent calls.');
+            $previous[] = $result;
+        }
+    }
+
+    /**
+     * @test
+     * @return void
+     */
+    public function testGetPriorityMethodReturnsInteger()
+    {
+        $this->assertInternalType('integer', CSPRNGenerator::getPriority(), 'Generator should express priority as an integer value.');
+        $this->assertTrue(0 < CSPRNGenerator::getPriority() && 4 > CSPRNGenerator::getPriority(), 'Generator should have a priority between 1 and 3.');
+    }
+
+}
+