AES: rm redundant setKey() method and fix setKeyLength()

phpseclib/Crypt/AES.php

@@ -155,43 +155,13 @@ class Crypt_AES extends Crypt_Rijndael
      */
     function setKeyLength($length)
     {
-        switch ($length) {
-            case 160:
-                $length = 192;
-                break;
-            case 224:
-                $length = 256;
-        }
         parent::setKeyLength($length);
-    }
+        switch ($this->key_length) {
-
+            case 20:
-    /**
-     * Sets the key.
-     *
-     * Rijndael supports five different key lengths, AES only supports three.
-     *
-     * @see Crypt_Rijndael:setKey()
-     * @see setKeyLength()
-     * @access public
-     * @param string $key
-     */
-    function setKey($key)
-    {
-        parent::setKey($key);
-
-        if (!$this->explicit_key_length) {
-            $length = strlen($key);
-            switch (true) {
-                case $length <= 16:
-                    $this->key_length = 16;
-                    break;
-                case $length <= 24:
                 $this->key_length = 24;
                 break;
-                default:
+            case 28:
                 $this->key_length = 32;
         }
-            $this->_setEngine();
-        }
     }
 }

tests/Unit/Crypt/AES/TestCase.php

@@ -370,6 +370,35 @@ abstract class Unit_Crypt_AES_TestCase extends PhpseclibTestCase
         $this->assertSame($aes->getKeyLength(), 256);
     }
 
+    public function testInvalidLengthKeyWithAES()
+    {
+        $plaintext = str_repeat('x', 16);
+
+        $aes = new Crypt_Rijndael();
+        $aes->setKey(str_repeat('a', 19));
+        $this->assertSame($aes->getKeyLength(), 160);
+
+        $ref = new Crypt_Rijndael();
+        $ref->setKey(str_repeat('a', 19) . "\0");
+        $this->assertSame(
+            bin2hex($aes->encrypt($plaintext)),
+            bin2hex($ref->encrypt($plaintext)),
+            'actual and expected value do not match for 168 bit Rijndael'
+        );
+
+        $aes = new Crypt_AES();
+        $aes->setKey(str_repeat('a', 19));
+        $this->assertSame($aes->getKeyLength(), 192);
+
+        $ref = new Crypt_AES();
+        $ref->setKey(str_repeat('a', 19) . "\0\0\0\0\0");
+        $this->assertSame(
+            bin2hex($aes->encrypt($plaintext)),
+            bin2hex($ref->encrypt($plaintext)),
+            'actual and expected value do not match for 168 bit AES'
+        );
+    }
+
     /**
      * @group github938
      */