Backport CFB8 support from master

phpseclib/Crypt/Base.php

@@ -76,6 +76,10 @@ abstract class Base
      * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher_feedback_.28CFB.29
      */
     const MODE_CFB = 3;
+    /**
+     * Encrypt / decrypt using the Cipher Feedback mode (8bit)
+     */
+    const MODE_CFB8 = 38;
     /**
      * Encrypt / decrypt using the Output Feedback mode.
      *
@@ -479,6 +483,7 @@ abstract class Base
                 break;
             case self::MODE_CTR:
             case self::MODE_CFB:
+            case self::MODE_CFB8:
             case self::MODE_OFB:
             case self::MODE_STREAM:
                 $this->mode = $mode;
@@ -762,6 +767,16 @@ abstract class Base
                         $iv = substr($ciphertext, -$this->block_size);
                     }
 
+                    return $ciphertext;
+                case self::MODE_CFB8:
+                    $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, $this->openssl_options, $this->encryptIV);
+                    if ($this->continuousBuffer) {
+                        if (($len = strlen($ciphertext)) >= $this->block_size) {
+                            $this->encryptIV = substr($ciphertext, -$this->block_size);
+                        } else {
+                            $this->encryptIV = substr($this->encryptIV, $len - $this->block_size) . substr($ciphertext, -$len);
+                        }
+                    }
                     return $ciphertext;
                 case self::MODE_OFB:
                     return $this->_openssl_ofb_process($plaintext, $this->encryptIV, $this->enbuffer);
@@ -942,6 +957,24 @@ abstract class Base
                     $pos = $len;
                 }
                 break;
+            case self::MODE_CFB8:
+                $ciphertext = '';
+                $len = strlen($plaintext);
+                $iv = $this->encryptIV;
+
+                for ($i = 0; $i < $len; ++$i) {
+                    $ciphertext .= ($c = $plaintext[$i] ^ $this->_encryptBlock($iv));
+                    $iv = substr($iv, 1) . $c;
+                }
+
+                if ($this->continuousBuffer) {
+                    if ($len >= $block_size) {
+                        $this->encryptIV = substr($ciphertext, -$block_size);
+                    } else {
+                        $this->encryptIV = substr($this->encryptIV, $len - $block_size) . substr($ciphertext, -$len);
+                    }
+                }
+                break;
             case self::MODE_OFB:
                 $xor = $this->encryptIV;
                 if (strlen($buffer['xor'])) {
@@ -1072,6 +1105,16 @@ abstract class Base
                         $iv = substr($ciphertext, -$this->block_size);
                     }
                     break;
+                case self::MODE_CFB8:
+                    $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, $this->openssl_options, $this->decryptIV);
+                    if ($this->continuousBuffer) {
+                        if (($len = strlen($ciphertext)) >= $this->block_size) {
+                            $this->decryptIV = substr($ciphertext, -$this->block_size);
+                        } else {
+                            $this->decryptIV = substr($this->decryptIV, $len - $this->block_size) . substr($ciphertext, -$len);
+                        }
+                    }
+                    break;
                 case self::MODE_OFB:
                     $plaintext = $this->_openssl_ofb_process($ciphertext, $this->decryptIV, $this->debuffer);
             }
@@ -1235,6 +1278,24 @@ abstract class Base
                     $pos = $len;
                 }
                 break;
+            case self::MODE_CFB8:
+                $plaintext = '';
+                $len = strlen($ciphertext);
+                $iv = $this->decryptIV;
+
+                for ($i = 0; $i < $len; ++$i) {
+                    $plaintext .= $ciphertext[$i] ^ $this->_encryptBlock($iv);
+                    $iv = substr($iv, 1) . $ciphertext[$i];
+                }
+
+                if ($this->continuousBuffer) {
+                    if ($len >= $block_size) {
+                        $this->decryptIV = substr($ciphertext, -$block_size);
+                    } else {
+                        $this->decryptIV = substr($this->decryptIV, $len - $block_size) . substr($ciphertext, -$len);
+                    }
+                }
+                break;
             case self::MODE_OFB:
                 $xor = $this->decryptIV;
                 if (strlen($buffer['xor'])) {
@@ -1435,6 +1496,8 @@ abstract class Base
                 return 'ctr';
             case self::MODE_CFB:
                 return 'cfb';
+            case self::MODE_CFB8:
+                return 'cfb8';
             case self::MODE_OFB:
                 return 'ofb';
         }
@@ -1788,6 +1851,7 @@ abstract class Base
                 self::MODE_ECB    => MCRYPT_MODE_ECB,
                 self::MODE_CBC    => MCRYPT_MODE_CBC,
                 self::MODE_CFB    => 'ncfb',
+                self::MODE_CFB8   => MCRYPT_MODE_CFB,
                 self::MODE_OFB    => MCRYPT_MODE_NOFB,
                 self::MODE_STREAM => MCRYPT_MODE_STREAM,
             );
@@ -2359,6 +2423,52 @@ abstract class Base
                         $_pos = $_len;
                     }
 
+                    return $_plaintext;
+                    ';
+                break;
+            case self::MODE_CFB8:
+                $encrypt = $init_encrypt . '
+                    $_ciphertext = "";
+                    $_len = strlen($_text);
+                    $_iv = $self->encryptIV;
+
+                    for ($_i = 0; $_i < $_len; ++$_i) {
+                        $in = $_iv;
+                        '.$encrypt_block.'
+                        $_ciphertext .= ($_c = $_text[$_i] ^ $in);
+                        $_iv = substr($_iv, 1) . $_c;
+                    }
+
+                    if ($self->continuousBuffer) {
+                        if ($_len >= '.$block_size.') {
+                            $self->encryptIV = substr($_ciphertext, -'.$block_size.');
+                        } else {
+                            $self->encryptIV = substr($self->encryptIV, $_len - '.$block_size.') . substr($_ciphertext, -$_len);
+                        }
+                    }
+
+                    return $_ciphertext;
+                    ';
+                $decrypt = $init_encrypt . '
+                    $_plaintext = "";
+                    $_len = strlen($_text);
+                    $_iv = $self->decryptIV;
+
+                    for ($_i = 0; $_i < $_len; ++$_i) {
+                        $in = $_iv;
+                        '.$encrypt_block.'
+                        $_plaintext .= $_text[$_i] ^ $in;
+                        $_iv = substr($_iv, 1) . $_text[$_i];
+                    }
+
+                    if ($self->continuousBuffer) {
+                        if ($_len >= '.$block_size.') {
+                            $self->decryptIV = substr($_text, -'.$block_size.');
+                        } else {
+                            $self->decryptIV = substr($self->decryptIV, $_len - '.$block_size.') . substr($_text, -$_len);
+                        }
+                    }
+
                     return $_plaintext;
                     ';
                 break;

tests/Unit/Crypt/AES/TestCase.php

@@ -39,6 +39,7 @@ abstract class Unit_Crypt_AES_TestCase extends PhpseclibTestCase
             Base::MODE_CTR,
             Base::MODE_OFB,
             Base::MODE_CFB,
+            Base::MODE_CFB8,
         );
         $plaintexts = array(
             '',
@@ -136,6 +137,7 @@ abstract class Unit_Crypt_AES_TestCase extends PhpseclibTestCase
             Base::MODE_CTR,
             Base::MODE_OFB,
             Base::MODE_CFB,
+            Base::MODE_CFB8,
         );
 
         $combos = array(