Implemented an mOTP generator.

src/Eloquent/Otis/Motp/Generator/MotpGenerator.php

@@ -0,0 +1,66 @@
+<?php
+
+/*
+ * This file is part of the Otis package.
+ *
+ * Copyright © 2013 Erin Millard
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Eloquent\Otis\Motp\Generator;
+
+use Icecave\Isolator\Isolator;
+
+/**
+ * Generates mOTP values.
+ */
+class MotpGenerator implements MotpGeneratorInterface
+{
+    /**
+     * Construct a new mOTP generator.
+     *
+     * @param Isolator|null $isolator The isolator to use.
+     */
+    public function __construct(Isolator $isolator = null)
+    {
+        $this->isolator = Isolator::get($isolator);
+    }
+
+    /**
+     * Generate an mOTP value.
+     *
+     * @link http://motp.sourceforge.net/#1.1
+     *
+     * @param string       $secret The shared secret.
+     * @param string       $pin    The PIN.
+     * @param integer|null $time   The Unix timestamp to generate the password for.
+     *
+     * @return string The generated mOTP value.
+     */
+    public function generate($secret, $pin, $time = null)
+    {
+        if (null === $time) {
+            $time = $this->isolator()->time();
+        }
+
+        return substr(
+            md5(strval(intval($time / 10)) . bin2hex($secret) . $pin),
+            0,
+            6
+        );
+    }
+
+    /**
+     * Get the isolator.
+     *
+     * @return Isolator The isolator.
+     */
+    protected function isolator()
+    {
+        return $this->isolator;
+    }
+
+    private $isolator;
+}

src/Eloquent/Otis/Motp/Generator/MotpGeneratorInterface.php

@@ -0,0 +1,31 @@
+<?php
+
+/*
+ * This file is part of the Otis package.
+ *
+ * Copyright © 2013 Erin Millard
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Eloquent\Otis\Motp\Generator;
+
+/**
+ * The interface implemented by mOTP generators.
+ */
+interface MotpGeneratorInterface
+{
+    /**
+     * Generate an mOTP value.
+     *
+     * @link http://motp.sourceforge.net/#1.1
+     *
+     * @param string       $secret The shared secret.
+     * @param string       $pin    The PIN.
+     * @param integer|null $time   The Unix timestamp to generate the password for.
+     *
+     * @return string The generated mOTP value.
+     */
+    public function generate($secret, $pin, $time = null);
+}

src/Eloquent/Otis/Totp/Generator/TotpGeneratorInterface.php

@@ -35,6 +35,6 @@ public function generate(
         $secret,
         $window = null,
         $time = null,
-        HotpHashAlgorithm $lagorithm = null
+        HotpHashAlgorithm $algorithm = null
     );
 }

test/suite/Eloquent/Otis/Motp/Generator/MotpGeneratorTest.php

@@ -0,0 +1,56 @@
+<?php
+
+/*
+ * This file is part of the Otis package.
+ *
+ * Copyright © 2013 Erin Millard
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Eloquent\Otis\Motp\Generator;
+
+use Icecave\Isolator\Isolator;
+use PHPUnit_Framework_TestCase;
+use Phake;
+
+class MotpGeneratorTest extends PHPUnit_Framework_TestCase
+{
+    protected function setUp()
+    {
+        parent::setUp();
+
+        $this->isolator = Phake::mock(Isolator::className());
+        $this->generator = new MotpGenerator($this->isolator);
+    }
+
+    public function generateData()
+    {
+        //                                secret                          pin     time        expected
+        return array(
+            'Known good value 1' => array('12345678',                     '1234', 0,          'd64c7d'),
+            'Known good value 2' => array('12345678',                     '1234', 9,          'd64c7d'),
+            'Known good value 3' => array('12345678',                     '1234', 1234,       '6bfed1'),
+            'Known good value 4' => array('12345678',                     '1234', 1240,       'ee20ed'),
+            'Known good value 5' => array(pack('H*', 'fd85e62d9beb4542'), '1234', 1379424174, '65e5e8'),
+        );
+    }
+
+    /**
+     * @dataProvider generateData
+     */
+    public function testGenerate($secret, $pin, $time, $motp)
+    {
+        $result = $this->generator->generate($secret, $pin, $time);
+
+        $this->assertSame($motp, $result);
+    }
+
+    public function testGenerateCurrentTime()
+    {
+        Phake::when($this->isolator)->time()->thenReturn(1234);
+
+        $this->assertSame('6bfed1', $this->generator->generate('12345678', '1234', null));
+    }
+}