diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2684f26..8937916 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Added
 - Whirlpool hash algorithm
 - 'Prepend salt' toggle
+- Drupal 7 hash algorithm
 ### Fixed
 - Error when 'Display name' not set
 - Encoding of iteration for 'Extended DES (Crypt)'
diff --git a/README.md b/README.md
index 8bccbcf..f99d4fb 100644
--- a/README.md
+++ b/README.md
@@ -190,6 +190,7 @@ MD5 (Crypt) | | $1$RzaFbNcU$u9adfTY/Q6za6nu0Ogrl1/
 SHA256 (Crypt) | Generates hash with 5000 rounds. | $5$rounds=5000$VIYD0iHkg7uY9SRc$v2XLS/9dvfFN84mzGvW9wxnVt9Xd/urXaaTkpW8EwD1
 SHA512 (Crypt) | Generates hash with 5000 rounds. | $6$rounds=5000$yH.Q0OL4qbCOUJ3q$Xry5EVFva3wKnfo8/ktrugmBd8tcl34NK6rXInv1HhmdSUNLEm0La9JnA57rqwQ.9/Bz513MD4tvmmISLUIHs/
 Standard DES (Crypt) | | yTBnb7ab/N072
+Drupal 7 | See [phpass](http://www.openwall.com/phpass/). | $S$DC7eCpJQ3SUQtW4Bp.vKb2rpeaffi4iqk9OpYwJyEoSMsezn67Sl
 Joomla MD5 Encryption | Generates 32 chars salt. | 14d21b49b0f13e2acba962b6b0039edd:haJK0yTvBXTNMh76xwEw5RYEVpJsN8us
 MD5 | No salt supported. | 5f4dcc3b5aa765d61d8327deb882cf99
 Portable PHP password | See [phpass](http://www.openwall.com/phpass/). | $P$BxrwraqNTi4as0EI.IpiA/K.muk9ke/
diff --git a/lib/Crypto/Drupal7.php b/lib/Crypto/Drupal7.php
index 5b32a91..567e342 100644
--- a/lib/Crypto/Drupal7.php
+++ b/lib/Crypto/Drupal7.php
@@ -21,54 +21,34 @@
 
 namespace OCA\UserSQL\Crypto;
 
-use OCP\IL10N;
-
-require_once "Phpass.php";
-
 /**
  * Drupal 7 overrides of phpass hash implementation.
  *
  * @author BrandonKerr
+ * @author Marcin Łojewski <dev@mlojewski.me>
  */
 class Drupal7 extends Phpass
 {
-	
-	/**
-	 * The expected (and maximum) number of characters in a hashed password.
-	 */
-	const DRUPAL_HASH_LENGTH = 55;
+    /**
+     * The expected (and maximum) number of characters in a hashed password.
+     */
+    const DRUPAL_HASH_LENGTH = 55;
 
     /**
-     * @param string $password Password to encrypt.
-     * @param string $setting  Hash settings.
-     *
-     * @return string|null Generated hash. Null on invalid settings.
+     * @inheritdoc
      */
-    private function crypt($password, $setting)
+    protected function crypt($password, $setting)
     {
-        $countLog2 = strpos(self::ITOA64, $setting[3]);
-        if ($countLog2 < 7 || $countLog2 > 30) {
-            return null;
-        }
-
-        $count = 1 << $countLog2;
-
-        $salt = substr($setting, 4, 8);
-        if (strlen($salt) !== 8) {
-            return null;
-        }
-
-        $hash = hash('sha512', $salt . $password, true);
-        do {
-            $hash = hash('sha512', $hash . $password, true);
-        } while (--$count);
-
-        $output = substr($setting, 0, 12);
-        $output .= $this->encode64($hash, strlen($hash));
-
-        return substr($output, 0, self::DRUPAL_HASH_LENGTH);
+        return substr(parent::crypt($password, $setting), 0, self::DRUPAL_HASH_LENGTH);
     }
 
+    /**
+     * @inheritdoc
+     */
+    protected function hash($input)
+    {
+        return hash('sha512', $input, true);
+    }
 
     /**
      * @inheritdoc
diff --git a/lib/Crypto/Phpass.php b/lib/Crypto/Phpass.php
index d193917..a430ae3 100644
--- a/lib/Crypto/Phpass.php
+++ b/lib/Crypto/Phpass.php
@@ -61,7 +61,7 @@ class Phpass extends AbstractAlgorithm
      *
      * @return string|null Generated hash. Null on invalid settings.
      */
-    private function crypt($password, $setting)
+    protected function crypt($password, $setting)
     {
         $countLog2 = strpos(self::ITOA64, $setting[3]);
         if ($countLog2 < 7 || $countLog2 > 30) {
@@ -75,17 +75,29 @@ class Phpass extends AbstractAlgorithm
             return null;
         }
 
-        $hash = md5($salt . $password, true);
+        $hash = $this->hash($salt . $password);
         do {
-            $hash = md5($hash . $password, true);
+            $hash = $this->hash($hash . $password);
         } while (--$count);
 
         $output = substr($setting, 0, 12);
-        $output .= $this->encode64($hash, 16);
+        $output .= $this->encode64($hash, strlen($hash));
 
         return $output;
     }
 
+    /**
+     * Apply hash function to input.
+     *
+     * @param string $input Input string.
+     *
+     * @return string Hashed input.
+     */
+    protected function hash($input)
+    {
+        return md5($input, true);
+    }
+
     /**
      * Encode binary input to base64 string.
      *
diff --git a/tests/Crypto/Drupal7Test.php b/tests/Crypto/Drupal7Test.php
new file mode 100644
index 0000000..834fcff
--- /dev/null
+++ b/tests/Crypto/Drupal7Test.php
@@ -0,0 +1,61 @@
+<?php
+/**
+ * Nextcloud - user_sql
+ *
+ * @copyright 2018 Marcin Łojewski <dev@mlojewski.me>
+ * @author    Marcin Łojewski <dev@mlojewski.me>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace Tests\UserSQL\Crypto;
+
+use OCA\UserSQL\Crypto\Drupal7;
+use OCA\UserSQL\Crypto\IPasswordAlgorithm;
+use OCP\IL10N;
+use Test\TestCase;
+
+/**
+ * Unit tests for class <code>Drupal7</code>.
+ *
+ * @author Marcin Łojewski <dev@mlojewski.me>
+ */
+class Drupal7Test extends TestCase
+{
+    /**
+     * @var IPasswordAlgorithm
+     */
+    private $crypto;
+
+    public function testCheckPassword()
+    {
+        $this->assertTrue(
+            $this->crypto->checkPassword(
+                "password", "\$S\$DC7eCpJQ3SUQtW4Bp.vKb2rpeaffi4iqk9OpYwJyEoSMsezn67Sl"
+            )
+        );
+    }
+
+    public function testPasswordHash()
+    {
+        $hash = $this->crypto->getPasswordHash("password");
+        $this->assertTrue($this->crypto->checkPassword("password", $hash));
+    }
+
+    protected function setUp()
+    {
+        parent::setUp();
+        $this->crypto = new Drupal7($this->createMock(IL10N::class));
+    }
+}