--- /dev/null
+<?php
+
+/**
+ * Base Class for all Crypt_* cipher classes
+ *
+ * PHP versions 4 and 5
+ *
+ * Internally for phpseclib developers:
+ * If you plan to add a new cipher class, please note following rules:
+ *
+ * - The new Crypt_* cipher class should extend Crypt_Base
+ *
+ * - Following methods are then required to be overridden/overloaded:
+ *
+ * - _encryptBlock()
+ *
+ * - _decryptBlock()
+ *
+ * - _setupKey()
+ *
+ * - All other methods are optional to be overridden/overloaded
+ *
+ * - Look at the source code of the current ciphers how they extend Crypt_Base
+ * and take one of them as a start up for the new cipher class.
+ *
+ * - Please read all the other comments/notes/hints here also for each class var/method
+ *
+ * LICENSE: Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @category Crypt
+ * @package Crypt_Base
+ * @author Jim Wigginton <terrafrost@php.net>
+ * @author Hans-Juergen Petrich <petrich@tronic-media.com>
+ * @copyright 2007 Jim Wigginton
+ * @license http://www.opensource.org/licenses/mit-license.html MIT License
+ * @link http://phpseclib.sourceforge.net
+ */
+
+/**#@+
+ * @access public
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ */
+/**
+ * Encrypt / decrypt using the Counter mode.
+ *
+ * Set to -1 since that's what Crypt/Random.php uses to index the CTR mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Counter_.28CTR.29
+ */
+define('CRYPT_MODE_CTR', -1);
+/**
+ * Encrypt / decrypt using the Electronic Code Book mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Electronic_codebook_.28ECB.29
+ */
+define('CRYPT_MODE_ECB', 1);
+/**
+ * Encrypt / decrypt using the Code Book Chaining mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher-block_chaining_.28CBC.29
+ */
+define('CRYPT_MODE_CBC', 2);
+/**
+ * Encrypt / decrypt using the Cipher Feedback mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher_feedback_.28CFB.29
+ */
+define('CRYPT_MODE_CFB', 3);
+/**
+ * Encrypt / decrypt using the Output Feedback mode.
+ *
+ * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29
+ */
+define('CRYPT_MODE_OFB', 4);
+/**
+ * Encrypt / decrypt using streaming mode.
+ *
+ */
+define('CRYPT_MODE_STREAM', 5);
+/**#@-*/
+
+/**#@+
+ * @access private
+ * @see Crypt_Base::Crypt_Base()
+ */
+/**
+ * Base value for the internal implementation $engine switch
+ */
+define('CRYPT_MODE_INTERNAL', 1);
+/**
+ * Base value for the mcrypt implementation $engine switch
+ */
+define('CRYPT_MODE_MCRYPT', 2);
+/**#@-*/
+
+/**
+ * Base Class for all Crypt_* cipher classes
+ *
+ * @package Crypt_Base
+ * @author Jim Wigginton <terrafrost@php.net>
+ * @author Hans-Juergen Petrich <petrich@tronic-media.com>
+ * @access public
+ */
+class Crypt_Base
+{
+ /**
+ * The Encryption Mode
+ *
+ * @see Crypt_Base::Crypt_Base()
+ * @var Integer
+ * @access private
+ */
+ var $mode;
+
+ /**
+ * The Block Length of the block cipher
+ *
+ * @var Integer
+ * @access private
+ */
+ var $block_size = 16;
+
+ /**
+ * The Key
+ *
+ * @see Crypt_Base::setKey()
+ * @var String
+ * @access private
+ */
+ var $key = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
+
+ /**
+ * The Initialization Vector
+ *
+ * @see Crypt_Base::setIV()
+ * @var String
+ * @access private
+ */
+ var $iv;
+
+ /**
+ * A "sliding" Initialization Vector
+ *
+ * @see Crypt_Base::enableContinuousBuffer()
+ * @see Crypt_Base::_clearBuffers()
+ * @var String
+ * @access private
+ */
+ var $encryptIV;
+
+ /**
+ * A "sliding" Initialization Vector
+ *
+ * @see Crypt_Base::enableContinuousBuffer()
+ * @see Crypt_Base::_clearBuffers()
+ * @var String
+ * @access private
+ */
+ var $decryptIV;
+
+ /**
+ * Continuous Buffer status
+ *
+ * @see Crypt_Base::enableContinuousBuffer()
+ * @var Boolean
+ * @access private
+ */
+ var $continuousBuffer = false;
+
+ /**
+ * Encryption buffer for CTR, OFB and CFB modes
+ *
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::_clearBuffers()
+ * @var Array
+ * @access private
+ */
+ var $enbuffer;
+
+ /**
+ * Decryption buffer for CTR, OFB and CFB modes
+ *
+ * @see Crypt_Base::decrypt()
+ * @see Crypt_Base::_clearBuffers()
+ * @var Array
+ * @access private
+ */
+ var $debuffer;
+
+ /**
+ * mcrypt resource for encryption
+ *
+ * The mcrypt resource can be recreated every time something needs to be created or it can be created just once.
+ * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode.
+ *
+ * @see Crypt_Base::encrypt()
+ * @var Resource
+ * @access private
+ */
+ var $enmcrypt;
+
+ /**
+ * mcrypt resource for decryption
+ *
+ * The mcrypt resource can be recreated every time something needs to be created or it can be created just once.
+ * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode.
+ *
+ * @see Crypt_Base::decrypt()
+ * @var Resource
+ * @access private
+ */
+ var $demcrypt;
+
+ /**
+ * Does the enmcrypt resource need to be (re)initialized?
+ *
+ * @see Crypt_Twofish::setKey()
+ * @see Crypt_Twofish::setIV()
+ * @var Boolean
+ * @access private
+ */
+ var $enchanged = true;
+
+ /**
+ * Does the demcrypt resource need to be (re)initialized?
+ *
+ * @see Crypt_Twofish::setKey()
+ * @see Crypt_Twofish::setIV()
+ * @var Boolean
+ * @access private
+ */
+ var $dechanged = true;
+
+ /**
+ * mcrypt resource for CFB mode
+ *
+ * mcrypt's CFB mode, in (and only in) buffered context,
+ * is broken, so phpseclib implements the CFB mode by it self,
+ * even when the mcrypt php extension is available.
+ *
+ * In order to do the CFB-mode work (fast) phpseclib
+ * use a separate ECB-mode mcrypt resource.
+ *
+ * @link http://phpseclib.sourceforge.net/cfb-demo.phps
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ * @see Crypt_Base::_setupMcrypt()
+ * @var Resource
+ * @access private
+ */
+ var $ecb;
+
+ /**
+ * Optimizing value while CFB-encrypting
+ *
+ * Only relevant if $continuousBuffer enabled
+ * and $engine == CRYPT_MODE_MCRYPT
+ *
+ * It's faster to re-init $enmcrypt if
+ * $buffer bytes > $cfb_init_len than
+ * using the $ecb resource furthermore.
+ *
+ * This value depends of the chosen cipher
+ * and the time it would be needed for it's
+ * initialization [by mcrypt_generic_init()]
+ * which, typically, depends on the complexity
+ * on its internaly Key-expanding algorithm.
+ *
+ * @see Crypt_Base::encrypt()
+ * @var Integer
+ * @access private
+ */
+ var $cfb_init_len = 600;
+
+ /**
+ * Does internal cipher state need to be (re)initialized?
+ *
+ * @see setKey()
+ * @see setIV()
+ * @see disableContinuousBuffer()
+ * @var Boolean
+ * @access private
+ */
+ var $changed = true;
+
+ /**
+ * Padding status
+ *
+ * @see Crypt_Base::enablePadding()
+ * @var Boolean
+ * @access private
+ */
+ var $padding = true;
+
+ /**
+ * Is the mode one that is paddable?
+ *
+ * @see Crypt_Base::Crypt_Base()
+ * @var Boolean
+ * @access private
+ */
+ var $paddable = false;
+
+ /**
+ * Holds which crypt engine internaly should be use,
+ * which will be determined automatically on __construct()
+ *
+ * Currently available $engines are:
+ * - CRYPT_MODE_MCRYPT (fast, php-extension: mcrypt, extension_loaded('mcrypt') required)
+ * - CRYPT_MODE_INTERNAL (slower, pure php-engine, no php-extension required)
+ *
+ * In the pipeline... maybe. But currently not available:
+ * - CRYPT_MODE_OPENSSL (very fast, php-extension: openssl, extension_loaded('openssl') required)
+ *
+ * If possible, CRYPT_MODE_MCRYPT will be used for each cipher.
+ * Otherwise CRYPT_MODE_INTERNAL
+ *
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ * @var Integer
+ * @access private
+ */
+ var $engine;
+
+ /**
+ * The mcrypt specific name of the cipher
+ *
+ * Only used if $engine == CRYPT_MODE_MCRYPT
+ *
+ * @link http://www.php.net/mcrypt_module_open
+ * @link http://www.php.net/mcrypt_list_algorithms
+ * @see Crypt_Base::_setupMcrypt()
+ * @var String
+ * @access private
+ */
+ var $cipher_name_mcrypt;
+
+ /**
+ * The default password key_size used by setPassword()
+ *
+ * @see Crypt_Base::setPassword()
+ * @var Integer
+ * @access private
+ */
+ var $password_key_size = 32;
+
+ /**
+ * The default salt used by setPassword()
+ *
+ * @see Crypt_Base::setPassword()
+ * @var String
+ * @access private
+ */
+ var $password_default_salt = 'phpseclib/salt';
+
+ /**
+ * The namespace used by the cipher for its constants.
+ *
+ * ie: AES.php is using CRYPT_AES_MODE_* for its constants
+ * so $const_namespace is AES
+ *
+ * DES.php is using CRYPT_DES_MODE_* for its constants
+ * so $const_namespace is DES... and so on
+ *
+ * All CRYPT_<$const_namespace>_MODE_* are aliases of
+ * the generic CRYPT_MODE_* constants, so both could be used
+ * for each cipher.
+ *
+ * Example:
+ * $aes = new Crypt_AES(CRYPT_AES_MODE_CFB); // $aes will operate in cfb mode
+ * $aes = new Crypt_AES(CRYPT_MODE_CFB); // identical
+ *
+ * @see Crypt_Base::Crypt_Base()
+ * @var String
+ * @access private
+ */
+ var $const_namespace;
+
+ /**
+ * The name of the performance-optimized callback function
+ *
+ * Used by encrypt() / decrypt()
+ * only if $engine == CRYPT_MODE_INTERNAL
+ *
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ * @see Crypt_Base::_setupInlineCrypt()
+ * @see Crypt_Base::$use_inline_crypt
+ * @var Callback
+ * @access private
+ */
+ var $inline_crypt;
+
+ /**
+ * Holds whether performance-optimized $inline_crypt() can/should be used.
+ *
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ * @see Crypt_Base::inline_crypt
+ * @var mixed
+ * @access private
+ */
+ var $use_inline_crypt;
+
+ /**
+ * Default Constructor.
+ *
+ * Determines whether or not the mcrypt extension should be used.
+ *
+ * $mode could be:
+ *
+ * - CRYPT_MODE_ECB
+ *
+ * - CRYPT_MODE_CBC
+ *
+ * - CRYPT_MODE_CTR
+ *
+ * - CRYPT_MODE_CFB
+ *
+ * - CRYPT_MODE_OFB
+ *
+ * (or the alias constants of the chosen cipher, for example for AES: CRYPT_AES_MODE_ECB or CRYPT_AES_MODE_CBC ...)
+ *
+ * If not explicitly set, CRYPT_MODE_CBC will be used.
+ *
+ * @param optional Integer $mode
+ * @access public
+ */
+ function Crypt_Base($mode = CRYPT_MODE_CBC)
+ {
+ $const_crypt_mode = 'CRYPT_' . $this->const_namespace . '_MODE';
+
+ // Determining the availibility of mcrypt support for the cipher
+ if (!defined($const_crypt_mode)) {
+ switch (true) {
+ case extension_loaded('mcrypt') && in_array($this->cipher_name_mcrypt, mcrypt_list_algorithms()):
+ define($const_crypt_mode, CRYPT_MODE_MCRYPT);
+ break;
+ default:
+ define($const_crypt_mode, CRYPT_MODE_INTERNAL);
+ }
+ }
+
+ // Determining which internal $engine should be used.
+ // The fastes possible first.
+ switch (true) {
+ case empty($this->cipher_name_mcrypt): // The cipher module has no mcrypt-engine support at all so we force CRYPT_MODE_INTERNAL
+ $this->engine = CRYPT_MODE_INTERNAL;
+ break;
+ case constant($const_crypt_mode) == CRYPT_MODE_MCRYPT:
+ $this->engine = CRYPT_MODE_MCRYPT;
+ break;
+ default:
+ $this->engine = CRYPT_MODE_INTERNAL;
+ }
+
+ // $mode dependent settings
+ switch ($mode) {
+ case CRYPT_MODE_ECB:
+ $this->paddable = true;
+ $this->mode = $mode;
+ break;
+ case CRYPT_MODE_CTR:
+ case CRYPT_MODE_CFB:
+ case CRYPT_MODE_OFB:
+ case CRYPT_MODE_STREAM:
+ $this->mode = $mode;
+ break;
+ case CRYPT_MODE_CBC:
+ default:
+ $this->paddable = true;
+ $this->mode = CRYPT_MODE_CBC;
+ }
+
+ // Determining whether inline crypting can be used by the cipher
+ if ($this->use_inline_crypt !== false && function_exists('create_function')) {
+ $this->use_inline_crypt = true;
+ }
+ }
+
+ /**
+ * Sets the initialization vector. (optional)
+ *
+ * SetIV is not required when CRYPT_MODE_ECB (or ie for AES: CRYPT_AES_MODE_ECB) is being used. If not explicitly set, it'll be assumed
+ * to be all zero's.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @access public
+ * @param String $iv
+ */
+ function setIV($iv)
+ {
+ if ($this->mode == CRYPT_MODE_ECB) {
+ return;
+ }
+
+ $this->iv = $iv;
+ $this->changed = true;
+ }
+
+ /**
+ * Sets the key.
+ *
+ * The min/max length(s) of the key depends on the cipher which is used.
+ * If the key not fits the length(s) of the cipher it will paded with null bytes
+ * up to the closest valid key length. If the key is more than max length,
+ * we trim the excess bits.
+ *
+ * If the key is not explicitly set, it'll be assumed to be all null bytes.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @access public
+ * @param String $key
+ */
+ function setKey($key)
+ {
+ $this->key = $key;
+ $this->changed = true;
+ }
+
+ /**
+ * Sets the password.
+ *
+ * Depending on what $method is set to, setPassword()'s (optional) parameters are as follows:
+ * {@link http://en.wikipedia.org/wiki/PBKDF2 pbkdf2} or pbkdf1:
+ * $hash, $salt, $count, $dkLen
+ *
+ * Where $hash (default = sha1) currently supports the following hashes: see: Crypt/Hash.php
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see Crypt/Hash.php
+ * @param String $password
+ * @param optional String $method
+ * @return Boolean
+ * @access public
+ */
+ function setPassword($password, $method = 'pbkdf2')
+ {
+ $key = '';
+
+ switch ($method) {
+ default: // 'pbkdf2' or 'pbkdf1'
+ $func_args = func_get_args();
+
+ // Hash function
+ $hash = isset($func_args[2]) ? $func_args[2] : 'sha1';
+
+ // WPA and WPA2 use the SSID as the salt
+ $salt = isset($func_args[3]) ? $func_args[3] : $this->password_default_salt;
+
+ // RFC2898#section-4.2 uses 1,000 iterations by default
+ // WPA and WPA2 use 4,096.
+ $count = isset($func_args[4]) ? $func_args[4] : 1000;
+
+ // Keylength
+ if (isset($func_args[5])) {
+ $dkLen = $func_args[5];
+ } else {
+ $dkLen = $method == 'pbkdf1' ? 2 * $this->password_key_size : $this->password_key_size;
+ }
+
+ switch (true) {
+ case $method == 'pbkdf1':
+ if (!class_exists('Crypt_Hash')) {
+ include_once 'Crypt/Hash.php';
+ }
+ $hashObj = new Crypt_Hash();
+ $hashObj->setHash($hash);
+ if ($dkLen > $hashObj->getLength()) {
+ user_error('Derived key too long');
+ return false;
+ }
+ $t = $password . $salt;
+ for ($i = 0; $i < $count; ++$i) {
+ $t = $hashObj->hash($t);
+ }
+ $key = substr($t, 0, $dkLen);
+
+ $this->setKey(substr($key, 0, $dkLen >> 1));
+ $this->setIV(substr($key, $dkLen >> 1));
+
+ return true;
+ // Determining if php[>=5.5.0]'s hash_pbkdf2() function avail- and useable
+ case !function_exists('hash_pbkdf2'):
+ case !function_exists('hash_algos'):
+ case !in_array($hash, hash_algos()):
+ if (!class_exists('Crypt_Hash')) {
+ include_once 'Crypt/Hash.php';
+ }
+ $i = 1;
+ while (strlen($key) < $dkLen) {
+ $hmac = new Crypt_Hash();
+ $hmac->setHash($hash);
+ $hmac->setKey($password);
+ $f = $u = $hmac->hash($salt . pack('N', $i++));
+ for ($j = 2; $j <= $count; ++$j) {
+ $u = $hmac->hash($u);
+ $f^= $u;
+ }
+ $key.= $f;
+ }
+ $key = substr($key, 0, $dkLen);
+ break;
+ default:
+ $key = hash_pbkdf2($hash, $password, $salt, $count, $dkLen, true);
+ }
+ }
+
+ $this->setKey($key);
+
+ return true;
+ }
+
+ /**
+ * Encrypts a message.
+ *
+ * $plaintext will be padded with additional bytes such that it's length is a multiple of the block size. Other cipher
+ * implementations may or may not pad in the same manner. Other common approaches to padding and the reasons why it's
+ * necessary are discussed in the following
+ * URL:
+ *
+ * {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html}
+ *
+ * An alternative to padding is to, separately, send the length of the file. This is what SSH, in fact, does.
+ * strlen($plaintext) will still need to be a multiple of the block size, however, arbitrary values can be added to make it that
+ * length.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see Crypt_Base::decrypt()
+ * @access public
+ * @param String $plaintext
+ * @return String $cipertext
+ */
+ function encrypt($plaintext)
+ {
+ if ($this->engine == CRYPT_MODE_MCRYPT) {
+ if ($this->changed) {
+ $this->_setupMcrypt();
+ $this->changed = false;
+ }
+ if ($this->enchanged) {
+ mcrypt_generic_init($this->enmcrypt, $this->key, $this->encryptIV);
+ $this->enchanged = false;
+ }
+
+ // re: {@link http://phpseclib.sourceforge.net/cfb-demo.phps}
+ // using mcrypt's default handing of CFB the above would output two different things. using phpseclib's
+ // rewritten CFB implementation the above outputs the same thing twice.
+ if ($this->mode == CRYPT_MODE_CFB && $this->continuousBuffer) {
+ $block_size = $this->block_size;
+ $iv = &$this->encryptIV;
+ $pos = &$this->enbuffer['pos'];
+ $len = strlen($plaintext);
+ $ciphertext = '';
+ $i = 0;
+ if ($pos) {
+ $orig_pos = $pos;
+ $max = $block_size - $pos;
+ if ($len >= $max) {
+ $i = $max;
+ $len-= $max;
+ $pos = 0;
+ } else {
+ $i = $len;
+ $pos+= $len;
+ $len = 0;
+ }
+ $ciphertext = substr($iv, $orig_pos) ^ $plaintext;
+ $iv = substr_replace($iv, $ciphertext, $orig_pos, $i);
+ $this->enbuffer['enmcrypt_init'] = true;
+ }
+ if ($len >= $block_size) {
+ if ($this->enbuffer['enmcrypt_init'] === false || $len > $this->cfb_init_len) {
+ if ($this->enbuffer['enmcrypt_init'] === true) {
+ mcrypt_generic_init($this->enmcrypt, $this->key, $iv);
+ $this->enbuffer['enmcrypt_init'] = false;
+ }
+ $ciphertext.= mcrypt_generic($this->enmcrypt, substr($plaintext, $i, $len - $len % $block_size));
+ $iv = substr($ciphertext, -$block_size);
+ $len%= $block_size;
+ } else {
+ while ($len >= $block_size) {
+ $iv = mcrypt_generic($this->ecb, $iv) ^ substr($plaintext, $i, $block_size);
+ $ciphertext.= $iv;
+ $len-= $block_size;
+ $i+= $block_size;
+ }
+ }
+ }
+
+ if ($len) {
+ $iv = mcrypt_generic($this->ecb, $iv);
+ $block = $iv ^ substr($plaintext, -$len);
+ $iv = substr_replace($iv, $block, 0, $len);
+ $ciphertext.= $block;
+ $pos = $len;
+ }
+
+ return $ciphertext;
+ }
+
+ if ($this->paddable) {
+ $plaintext = $this->_pad($plaintext);
+ }
+
+ $ciphertext = mcrypt_generic($this->enmcrypt, $plaintext);
+
+ if (!$this->continuousBuffer) {
+ mcrypt_generic_init($this->enmcrypt, $this->key, $this->encryptIV);
+ }
+
+ return $ciphertext;
+ }
+
+ if ($this->changed) {
+ $this->_setup();
+ $this->changed = false;
+ }
+ if ($this->use_inline_crypt) {
+ $inline = $this->inline_crypt;
+ return $inline('encrypt', $this, $plaintext);
+ }
+ if ($this->paddable) {
+ $plaintext = $this->_pad($plaintext);
+ }
+
+ $buffer = &$this->enbuffer;
+ $block_size = $this->block_size;
+ $ciphertext = '';
+ switch ($this->mode) {
+ case CRYPT_MODE_ECB:
+ for ($i = 0; $i < strlen($plaintext); $i+=$block_size) {
+ $ciphertext.= $this->_encryptBlock(substr($plaintext, $i, $block_size));
+ }
+ break;
+ case CRYPT_MODE_CBC:
+ $xor = $this->encryptIV;
+ for ($i = 0; $i < strlen($plaintext); $i+=$block_size) {
+ $block = substr($plaintext, $i, $block_size);
+ $block = $this->_encryptBlock($block ^ $xor);
+ $xor = $block;
+ $ciphertext.= $block;
+ }
+ if ($this->continuousBuffer) {
+ $this->encryptIV = $xor;
+ }
+ break;
+ case CRYPT_MODE_CTR:
+ $xor = $this->encryptIV;
+ if (strlen($buffer['encrypted'])) {
+ for ($i = 0; $i < strlen($plaintext); $i+=$block_size) {
+ $block = substr($plaintext, $i, $block_size);
+ if (strlen($block) > strlen($buffer['encrypted'])) {
+ $buffer['encrypted'].= $this->_encryptBlock($this->_generateXor($xor, $block_size));
+ }
+ $key = $this->_stringShift($buffer['encrypted'], $block_size);
+ $ciphertext.= $block ^ $key;
+ }
+ } else {
+ for ($i = 0; $i < strlen($plaintext); $i+=$block_size) {
+ $block = substr($plaintext, $i, $block_size);
+ $key = $this->_encryptBlock($this->_generateXor($xor, $block_size));
+ $ciphertext.= $block ^ $key;
+ }
+ }
+ if ($this->continuousBuffer) {
+ $this->encryptIV = $xor;
+ if ($start = strlen($plaintext) % $block_size) {
+ $buffer['encrypted'] = substr($key, $start) . $buffer['encrypted'];
+ }
+ }
+ break;
+ case CRYPT_MODE_CFB:
+ // cfb loosely routines inspired by openssl's:
+ // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1}
+ if ($this->continuousBuffer) {
+ $iv = &$this->encryptIV;
+ $pos = &$buffer['pos'];
+ } else {
+ $iv = $this->encryptIV;
+ $pos = 0;
+ }
+ $len = strlen($plaintext);
+ $i = 0;
+ if ($pos) {
+ $orig_pos = $pos;
+ $max = $block_size - $pos;
+ if ($len >= $max) {
+ $i = $max;
+ $len-= $max;
+ $pos = 0;
+ } else {
+ $i = $len;
+ $pos+= $len;
+ $len = 0;
+ }
+ // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+ $ciphertext = substr($iv, $orig_pos) ^ $plaintext;
+ $iv = substr_replace($iv, $ciphertext, $orig_pos, $i);
+ }
+ while ($len >= $block_size) {
+ $iv = $this->_encryptBlock($iv) ^ substr($plaintext, $i, $block_size);
+ $ciphertext.= $iv;
+ $len-= $block_size;
+ $i+= $block_size;
+ }
+ if ($len) {
+ $iv = $this->_encryptBlock($iv);
+ $block = $iv ^ substr($plaintext, $i);
+ $iv = substr_replace($iv, $block, 0, $len);
+ $ciphertext.= $block;
+ $pos = $len;
+ }
+ break;
+ case CRYPT_MODE_OFB:
+ $xor = $this->encryptIV;
+ if (strlen($buffer['xor'])) {
+ for ($i = 0; $i < strlen($plaintext); $i+=$block_size) {
+ $block = substr($plaintext, $i, $block_size);
+ if (strlen($block) > strlen($buffer['xor'])) {
+ $xor = $this->_encryptBlock($xor);
+ $buffer['xor'].= $xor;
+ }
+ $key = $this->_stringShift($buffer['xor'], $block_size);
+ $ciphertext.= $block ^ $key;
+ }
+ } else {
+ for ($i = 0; $i < strlen($plaintext); $i+=$block_size) {
+ $xor = $this->_encryptBlock($xor);
+ $ciphertext.= substr($plaintext, $i, $block_size) ^ $xor;
+ }
+ $key = $xor;
+ }
+ if ($this->continuousBuffer) {
+ $this->encryptIV = $xor;
+ if ($start = strlen($plaintext) % $block_size) {
+ $buffer['xor'] = substr($key, $start) . $buffer['xor'];
+ }
+ }
+ break;
+ case CRYPT_MODE_STREAM:
+ $ciphertext = $this->_encryptBlock($plaintext);
+ break;
+ }
+
+ return $ciphertext;
+ }
+
+ /**
+ * Decrypts a message.
+ *
+ * If strlen($ciphertext) is not a multiple of the block size, null bytes will be added to the end of the string until
+ * it is.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see Crypt_Base::encrypt()
+ * @access public
+ * @param String $ciphertext
+ * @return String $plaintext
+ */
+ function decrypt($ciphertext)
+ {
+ if ($this->engine == CRYPT_MODE_MCRYPT) {
+ $block_size = $this->block_size;
+ if ($this->changed) {
+ $this->_setupMcrypt();
+ $this->changed = false;
+ }
+ if ($this->dechanged) {
+ mcrypt_generic_init($this->demcrypt, $this->key, $this->decryptIV);
+ $this->dechanged = false;
+ }
+
+ if ($this->mode == CRYPT_MODE_CFB && $this->continuousBuffer) {
+ $iv = &$this->decryptIV;
+ $pos = &$this->debuffer['pos'];
+ $len = strlen($ciphertext);
+ $plaintext = '';
+ $i = 0;
+ if ($pos) {
+ $orig_pos = $pos;
+ $max = $block_size - $pos;
+ if ($len >= $max) {
+ $i = $max;
+ $len-= $max;
+ $pos = 0;
+ } else {
+ $i = $len;
+ $pos+= $len;
+ $len = 0;
+ }
+ // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+ $plaintext = substr($iv, $orig_pos) ^ $ciphertext;
+ $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i);
+ }
+ if ($len >= $block_size) {
+ $cb = substr($ciphertext, $i, $len - $len % $block_size);
+ $plaintext.= mcrypt_generic($this->ecb, $iv . $cb) ^ $cb;
+ $iv = substr($cb, -$block_size);
+ $len%= $block_size;
+ }
+ if ($len) {
+ $iv = mcrypt_generic($this->ecb, $iv);
+ $plaintext.= $iv ^ substr($ciphertext, -$len);
+ $iv = substr_replace($iv, substr($ciphertext, -$len), 0, $len);
+ $pos = $len;
+ }
+
+ return $plaintext;
+ }
+
+ if ($this->paddable) {
+ // we pad with chr(0) since that's what mcrypt_generic does. to quote from {@link http://www.php.net/function.mcrypt-generic}:
+ // "The data is padded with "\0" to make sure the length of the data is n * blocksize."
+ $ciphertext = str_pad($ciphertext, strlen($ciphertext) + ($block_size - strlen($ciphertext) % $block_size) % $block_size, chr(0));
+ }
+
+ $plaintext = mdecrypt_generic($this->demcrypt, $ciphertext);
+
+ if (!$this->continuousBuffer) {
+ mcrypt_generic_init($this->demcrypt, $this->key, $this->decryptIV);
+ }
+
+ return $this->paddable ? $this->_unpad($plaintext) : $plaintext;
+ }
+
+ if ($this->changed) {
+ $this->_setup();
+ $this->changed = false;
+ }
+ if ($this->use_inline_crypt) {
+ $inline = $this->inline_crypt;
+ return $inline('decrypt', $this, $ciphertext);
+ }
+
+ $block_size = $this->block_size;
+ if ($this->paddable) {
+ // we pad with chr(0) since that's what mcrypt_generic does [...]
+ $ciphertext = str_pad($ciphertext, strlen($ciphertext) + ($block_size - strlen($ciphertext) % $block_size) % $block_size, chr(0));
+ }
+
+ $buffer = &$this->debuffer;
+ $plaintext = '';
+ switch ($this->mode) {
+ case CRYPT_MODE_ECB:
+ for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) {
+ $plaintext.= $this->_decryptBlock(substr($ciphertext, $i, $block_size));
+ }
+ break;
+ case CRYPT_MODE_CBC:
+ $xor = $this->decryptIV;
+ for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) {
+ $block = substr($ciphertext, $i, $block_size);
+ $plaintext.= $this->_decryptBlock($block) ^ $xor;
+ $xor = $block;
+ }
+ if ($this->continuousBuffer) {
+ $this->decryptIV = $xor;
+ }
+ break;
+ case CRYPT_MODE_CTR:
+ $xor = $this->decryptIV;
+ if (strlen($buffer['ciphertext'])) {
+ for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) {
+ $block = substr($ciphertext, $i, $block_size);
+ if (strlen($block) > strlen($buffer['ciphertext'])) {
+ $buffer['ciphertext'].= $this->_encryptBlock($this->_generateXor($xor, $block_size));
+ }
+ $key = $this->_stringShift($buffer['ciphertext'], $block_size);
+ $plaintext.= $block ^ $key;
+ }
+ } else {
+ for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) {
+ $block = substr($ciphertext, $i, $block_size);
+ $key = $this->_encryptBlock($this->_generateXor($xor, $block_size));
+ $plaintext.= $block ^ $key;
+ }
+ }
+ if ($this->continuousBuffer) {
+ $this->decryptIV = $xor;
+ if ($start = strlen($ciphertext) % $block_size) {
+ $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext'];
+ }
+ }
+ break;
+ case CRYPT_MODE_CFB:
+ if ($this->continuousBuffer) {
+ $iv = &$this->decryptIV;
+ $pos = &$buffer['pos'];
+ } else {
+ $iv = $this->decryptIV;
+ $pos = 0;
+ }
+ $len = strlen($ciphertext);
+ $i = 0;
+ if ($pos) {
+ $orig_pos = $pos;
+ $max = $block_size - $pos;
+ if ($len >= $max) {
+ $i = $max;
+ $len-= $max;
+ $pos = 0;
+ } else {
+ $i = $len;
+ $pos+= $len;
+ $len = 0;
+ }
+ // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize
+ $plaintext = substr($iv, $orig_pos) ^ $ciphertext;
+ $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i);
+ }
+ while ($len >= $block_size) {
+ $iv = $this->_encryptBlock($iv);
+ $cb = substr($ciphertext, $i, $block_size);
+ $plaintext.= $iv ^ $cb;
+ $iv = $cb;
+ $len-= $block_size;
+ $i+= $block_size;
+ }
+ if ($len) {
+ $iv = $this->_encryptBlock($iv);
+ $plaintext.= $iv ^ substr($ciphertext, $i);
+ $iv = substr_replace($iv, substr($ciphertext, $i), 0, $len);
+ $pos = $len;
+ }
+ break;
+ case CRYPT_MODE_OFB:
+ $xor = $this->decryptIV;
+ if (strlen($buffer['xor'])) {
+ for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) {
+ $block = substr($ciphertext, $i, $block_size);
+ if (strlen($block) > strlen($buffer['xor'])) {
+ $xor = $this->_encryptBlock($xor);
+ $buffer['xor'].= $xor;
+ }
+ $key = $this->_stringShift($buffer['xor'], $block_size);
+ $plaintext.= $block ^ $key;
+ }
+ } else {
+ for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) {
+ $xor = $this->_encryptBlock($xor);
+ $plaintext.= substr($ciphertext, $i, $block_size) ^ $xor;
+ }
+ $key = $xor;
+ }
+ if ($this->continuousBuffer) {
+ $this->decryptIV = $xor;
+ if ($start = strlen($ciphertext) % $block_size) {
+ $buffer['xor'] = substr($key, $start) . $buffer['xor'];
+ }
+ }
+ break;
+ case CRYPT_MODE_STREAM:
+ $plaintext = $this->_decryptBlock($ciphertext);
+ break;
+ }
+ return $this->paddable ? $this->_unpad($plaintext) : $plaintext;
+ }
+
+ /**
+ * Pad "packets".
+ *
+ * Block ciphers working by encrypting between their specified [$this->]block_size at a time
+ * If you ever need to encrypt or decrypt something that isn't of the proper length, it becomes necessary to
+ * pad the input so that it is of the proper length.
+ *
+ * Padding is enabled by default. Sometimes, however, it is undesirable to pad strings. Such is the case in SSH,
+ * where "packets" are padded with random bytes before being encrypted. Unpad these packets and you risk stripping
+ * away characters that shouldn't be stripped away. (SSH knows how many bytes are added because the length is
+ * transmitted separately)
+ *
+ * @see Crypt_Base::disablePadding()
+ * @access public
+ */
+ function enablePadding()
+ {
+ $this->padding = true;
+ }
+
+ /**
+ * Do not pad packets.
+ *
+ * @see Crypt_Base::enablePadding()
+ * @access public
+ */
+ function disablePadding()
+ {
+ $this->padding = false;
+ }
+
+ /**
+ * Treat consecutive "packets" as if they are a continuous buffer.
+ *
+ * Say you have a 32-byte plaintext $plaintext. Using the default behavior, the two following code snippets
+ * will yield different outputs:
+ *
+ * <code>
+ * echo $rijndael->encrypt(substr($plaintext, 0, 16));
+ * echo $rijndael->encrypt(substr($plaintext, 16, 16));
+ * </code>
+ * <code>
+ * echo $rijndael->encrypt($plaintext);
+ * </code>
+ *
+ * The solution is to enable the continuous buffer. Although this will resolve the above discrepancy, it creates
+ * another, as demonstrated with the following:
+ *
+ * <code>
+ * $rijndael->encrypt(substr($plaintext, 0, 16));
+ * echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16)));
+ * </code>
+ * <code>
+ * echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16)));
+ * </code>
+ *
+ * With the continuous buffer disabled, these would yield the same output. With it enabled, they yield different
+ * outputs. The reason is due to the fact that the initialization vector's change after every encryption /
+ * decryption round when the continuous buffer is enabled. When it's disabled, they remain constant.
+ *
+ * Put another way, when the continuous buffer is enabled, the state of the Crypt_*() object changes after each
+ * encryption / decryption round, whereas otherwise, it'd remain constant. For this reason, it's recommended that
+ * continuous buffers not be used. They do offer better security and are, in fact, sometimes required (SSH uses them),
+ * however, they are also less intuitive and more likely to cause you problems.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see Crypt_Base::disableContinuousBuffer()
+ * @access public
+ */
+ function enableContinuousBuffer()
+ {
+ if ($this->mode == CRYPT_MODE_ECB) {
+ return;
+ }
+
+ $this->continuousBuffer = true;
+ }
+
+ /**
+ * Treat consecutive packets as if they are a discontinuous buffer.
+ *
+ * The default behavior.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see Crypt_Base::enableContinuousBuffer()
+ * @access public
+ */
+ function disableContinuousBuffer()
+ {
+ if ($this->mode == CRYPT_MODE_ECB) {
+ return;
+ }
+ if (!$this->continuousBuffer) {
+ return;
+ }
+
+ $this->continuousBuffer = false;
+ $this->changed = true;
+ }
+
+ /**
+ * Encrypts a block
+ *
+ * Note: Must extend by the child Crypt_* class
+ *
+ * @access private
+ * @param String $in
+ * @return String
+ */
+ function _encryptBlock($in)
+ {
+ user_error((version_compare(PHP_VERSION, '5.0.0', '>=') ? __METHOD__ : __FUNCTION__) . '() must extend by class ' . get_class($this), E_USER_ERROR);
+ }
+
+ /**
+ * Decrypts a block
+ *
+ * Note: Must extend by the child Crypt_* class
+ *
+ * @access private
+ * @param String $in
+ * @return String
+ */
+ function _decryptBlock($in)
+ {
+ user_error((version_compare(PHP_VERSION, '5.0.0', '>=') ? __METHOD__ : __FUNCTION__) . '() must extend by class ' . get_class($this), E_USER_ERROR);
+ }
+
+ /**
+ * Setup the key (expansion)
+ *
+ * Only used if $engine == CRYPT_MODE_INTERNAL
+ *
+ * Note: Must extend by the child Crypt_* class
+ *
+ * @see Crypt_Base::_setup()
+ * @access private
+ */
+ function _setupKey()
+ {
+ user_error((version_compare(PHP_VERSION, '5.0.0', '>=') ? __METHOD__ : __FUNCTION__) . '() must extend by class ' . get_class($this), E_USER_ERROR);
+ }
+
+ /**
+ * Setup the CRYPT_MODE_INTERNAL $engine
+ *
+ * (re)init, if necessary, the internal cipher $engine and flush all $buffers
+ * Used (only) if $engine == CRYPT_MODE_INTERNAL
+ *
+ * _setup() will be called each time if $changed === true
+ * typically this happens when using one or more of following public methods:
+ *
+ * - setKey()
+ *
+ * - setIV()
+ *
+ * - disableContinuousBuffer()
+ *
+ * - First run of encrypt() / decrypt() with no init-settings
+ *
+ * Internally: _setup() is called always before(!) en/decryption.
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see setKey()
+ * @see setIV()
+ * @see disableContinuousBuffer()
+ * @access private
+ */
+ function _setup()
+ {
+ $this->_clearBuffers();
+ $this->_setupKey();
+
+ if ($this->use_inline_crypt) {
+ $this->_setupInlineCrypt();
+ }
+ }
+
+ /**
+ * Setup the CRYPT_MODE_MCRYPT $engine
+ *
+ * (re)init, if necessary, the (ext)mcrypt resources and flush all $buffers
+ * Used (only) if $engine = CRYPT_MODE_MCRYPT
+ *
+ * _setupMcrypt() will be called each time if $changed === true
+ * typically this happens when using one or more of following public methods:
+ *
+ * - setKey()
+ *
+ * - setIV()
+ *
+ * - disableContinuousBuffer()
+ *
+ * - First run of encrypt() / decrypt()
+ *
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @see setKey()
+ * @see setIV()
+ * @see disableContinuousBuffer()
+ * @access private
+ */
+ function _setupMcrypt()
+ {
+ $this->_clearBuffers();
+ $this->enchanged = $this->dechanged = true;
+
+ if (!isset($this->enmcrypt)) {
+ static $mcrypt_modes = array(
+ CRYPT_MODE_CTR => 'ctr',
+ CRYPT_MODE_ECB => MCRYPT_MODE_ECB,
+ CRYPT_MODE_CBC => MCRYPT_MODE_CBC,
+ CRYPT_MODE_CFB => 'ncfb',
+ CRYPT_MODE_OFB => MCRYPT_MODE_NOFB,
+ CRYPT_MODE_STREAM => MCRYPT_MODE_STREAM,
+ );
+
+ $this->demcrypt = mcrypt_module_open($this->cipher_name_mcrypt, '', $mcrypt_modes[$this->mode], '');
+ $this->enmcrypt = mcrypt_module_open($this->cipher_name_mcrypt, '', $mcrypt_modes[$this->mode], '');
+
+ // we need the $ecb mcrypt resource (only) in MODE_CFB with enableContinuousBuffer()
+ // to workaround mcrypt's broken ncfb implementation in buffered mode
+ // see: {@link http://phpseclib.sourceforge.net/cfb-demo.phps}
+ if ($this->mode == CRYPT_MODE_CFB) {
+ $this->ecb = mcrypt_module_open($this->cipher_name_mcrypt, '', MCRYPT_MODE_ECB, '');
+ }
+
+ } // else should mcrypt_generic_deinit be called?
+
+ if ($this->mode == CRYPT_MODE_CFB) {
+ mcrypt_generic_init($this->ecb, $this->key, str_repeat("\0", $this->block_size));
+ }
+ }
+
+ /**
+ * Pads a string
+ *
+ * Pads a string using the RSA PKCS padding standards so that its length is a multiple of the blocksize.
+ * $this->block_size - (strlen($text) % $this->block_size) bytes are added, each of which is equal to
+ * chr($this->block_size - (strlen($text) % $this->block_size)
+ *
+ * If padding is disabled and $text is not a multiple of the blocksize, the string will be padded regardless
+ * and padding will, hence forth, be enabled.
+ *
+ * @see Crypt_Base::_unpad()
+ * @param String $text
+ * @access private
+ * @return String
+ */
+ function _pad($text)
+ {
+ $length = strlen($text);
+
+ if (!$this->padding) {
+ if ($length % $this->block_size == 0) {
+ return $text;
+ } else {
+ user_error("The plaintext's length ($length) is not a multiple of the block size ({$this->block_size})");
+ $this->padding = true;
+ }
+ }
+
+ $pad = $this->block_size - ($length % $this->block_size);
+
+ return str_pad($text, $length + $pad, chr($pad));
+ }
+
+ /**
+ * Unpads a string.
+ *
+ * If padding is enabled and the reported padding length is invalid the encryption key will be assumed to be wrong
+ * and false will be returned.
+ *
+ * @see Crypt_Base::_pad()
+ * @param String $text
+ * @access private
+ * @return String
+ */
+ function _unpad($text)
+ {
+ if (!$this->padding) {
+ return $text;
+ }
+
+ $length = ord($text[strlen($text) - 1]);
+
+ if (!$length || $length > $this->block_size) {
+ return false;
+ }
+
+ return substr($text, 0, -$length);
+ }
+
+ /**
+ * Clears internal buffers
+ *
+ * Clearing/resetting the internal buffers is done everytime
+ * after disableContinuousBuffer() or on cipher $engine (re)init
+ * ie after setKey() or setIV()
+ *
+ * Note: Could, but not must, extend by the child Crypt_* class
+ *
+ * @access public
+ */
+ function _clearBuffers()
+ {
+ $this->enbuffer = array('encrypted' => '', 'xor' => '', 'pos' => 0, 'enmcrypt_init' => true);
+ $this->debuffer = array('ciphertext' => '', 'xor' => '', 'pos' => 0, 'demcrypt_init' => true);
+
+ // mcrypt's handling of invalid's $iv:
+ // $this->encryptIV = $this->decryptIV = strlen($this->iv) == $this->block_size ? $this->iv : str_repeat("\0", $this->block_size);
+ $this->encryptIV = $this->decryptIV = str_pad(substr($this->iv, 0, $this->block_size), $this->block_size, "\0");
+ }
+
+ /**
+ * String Shift
+ *
+ * Inspired by array_shift
+ *
+ * @param String $string
+ * @param optional Integer $index
+ * @access private
+ * @return String
+ */
+ function _stringShift(&$string, $index = 1)
+ {
+ $substr = substr($string, 0, $index);
+ $string = substr($string, $index);
+ return $substr;
+ }
+
+ /**
+ * Generate CTR XOR encryption key
+ *
+ * Encrypt the output of this and XOR it against the ciphertext / plaintext to get the
+ * plaintext / ciphertext in CTR mode.
+ *
+ * @see Crypt_Base::decrypt()
+ * @see Crypt_Base::encrypt()
+ * @param String $iv
+ * @param Integer $length
+ * @access private
+ * @return String $xor
+ */
+ function _generateXor(&$iv, $length)
+ {
+ $xor = '';
+ $block_size = $this->block_size;
+ $num_blocks = floor(($length + ($block_size - 1)) / $block_size);
+ for ($i = 0; $i < $num_blocks; $i++) {
+ $xor.= $iv;
+ for ($j = 4; $j <= $block_size; $j+= 4) {
+ $temp = substr($iv, -$j, 4);
+ switch ($temp) {
+ case "\xFF\xFF\xFF\xFF":
+ $iv = substr_replace($iv, "\x00\x00\x00\x00", -$j, 4);
+ break;
+ case "\x7F\xFF\xFF\xFF":
+ $iv = substr_replace($iv, "\x80\x00\x00\x00", -$j, 4);
+ break 2;
+ default:
+ extract(unpack('Ncount', $temp));
+ $iv = substr_replace($iv, pack('N', $count + 1), -$j, 4);
+ break 2;
+ }
+ }
+ }
+
+ return $xor;
+ }
+
+ /**
+ * Setup the performance-optimized function for de/encrypt()
+ *
+ * Stores the created (or existing) callback function-name
+ * in $this->inline_crypt
+ *
+ * Internally for phpseclib developers:
+ *
+ * _setupInlineCrypt() would be called only if:
+ *
+ * - $engine == CRYPT_MODE_INTERNAL and
+ *
+ * - $use_inline_crypt === true
+ *
+ * - each time on _setup(), after(!) _setupKey()
+ *
+ *
+ * This ensures that _setupInlineCrypt() has always a
+ * full ready2go initializated internal cipher $engine state
+ * where, for example, the keys allready expanded,
+ * keys/block_size calculated and such.
+ *
+ * It is, each time if called, the responsibility of _setupInlineCrypt():
+ *
+ * - to set $this->inline_crypt to a valid and fully working callback function
+ * as a (faster) replacement for encrypt() / decrypt()
+ *
+ * - NOT to create unlimited callback functions (for memory reasons!)
+ * no matter how often _setupInlineCrypt() would be called. At some
+ * point of amount they must be generic re-useable.
+ *
+ * - the code of _setupInlineCrypt() it self,
+ * and the generated callback code,
+ * must be, in following order:
+ * - 100% safe
+ * - 100% compatible to encrypt()/decrypt()
+ * - using only php5+ features/lang-constructs/php-extensions if
+ * compatibility (down to php4) or fallback is provided
+ * - readable/maintainable/understandable/commented and... not-cryptic-styled-code :-)
+ * - >= 10% faster than encrypt()/decrypt() [which is, by the way,
+ * the reason for the existence of _setupInlineCrypt() :-)]
+ * - memory-nice
+ * - short (as good as possible)
+ *
+ * Note: - _setupInlineCrypt() is using _createInlineCryptFunction() to create the full callback function code.
+ * - In case of using inline crypting, _setupInlineCrypt() must extend by the child Crypt_* class.
+ * - The following variable names are reserved:
+ * - $_* (all variable names prefixed with an underscore)
+ * - $self (object reference to it self. Do not use $this, but $self instead)
+ * - $in (the content of $in has to en/decrypt by the generated code)
+ * - The callback function should not use the 'return' statement, but en/decrypt'ing the content of $in only
+ *
+ *
+ * @see Crypt_Base::_setup()
+ * @see Crypt_Base::_createInlineCryptFunction()
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ * @access private
+ */
+ function _setupInlineCrypt()
+ {
+ // If a Crypt_* class providing inline crypting it must extend _setupInlineCrypt()
+
+ // If, for any reason, an extending Crypt_Base() Crypt_* class
+ // not using inline crypting then it must be ensured that: $this->use_inline_crypt = false
+ // ie in the class var declaration of $use_inline_crypt in general for the Crypt_* class,
+ // in the constructor at object instance-time
+ // or, if it's runtime-specific, at runtime
+
+ $this->use_inline_crypt = false;
+ }
+
+ /**
+ * Creates the performance-optimized function for en/decrypt()
+ *
+ * Internally for phpseclib developers:
+ *
+ * _createInlineCryptFunction():
+ *
+ * - merge the $cipher_code [setup'ed by _setupInlineCrypt()]
+ * with the current [$this->]mode of operation code
+ *
+ * - create the $inline function, which called by encrypt() / decrypt()
+ * as its replacement to speed up the en/decryption operations.
+ *
+ * - return the name of the created $inline callback function
+ *
+ * - used to speed up en/decryption
+ *
+ *
+ *
+ * The main reason why can speed up things [up to 50%] this way are:
+ *
+ * - using variables more effective then regular.
+ * (ie no use of expensive arrays but integers $k_0, $k_1 ...
+ * or even, for example, the pure $key[] values hardcoded)
+ *
+ * - avoiding 1000's of function calls of ie _encryptBlock()
+ * but inlining the crypt operations.
+ * in the mode of operation for() loop.
+ *
+ * - full loop unroll the (sometimes key-dependent) rounds
+ * avoiding this way ++$i counters and runtime-if's etc...
+ *
+ * The basic code architectur of the generated $inline en/decrypt()
+ * lambda function, in pseudo php, is:
+ *
+ * <code>
+ * +----------------------------------------------------------------------------------------------+
+ * | callback $inline = create_function: |
+ * | lambda_function_0001_crypt_ECB($action, $text) |
+ * | { |
+ * | INSERT PHP CODE OF: |
+ * | $cipher_code['init_crypt']; // general init code. |
+ * | // ie: $sbox'es declarations used for |
+ * | // encrypt and decrypt'ing. |
+ * | |
+ * | switch ($action) { |
+ * | case 'encrypt': |
+ * | INSERT PHP CODE OF: |
+ * | $cipher_code['init_encrypt']; // encrypt sepcific init code. |
+ * | ie: specified $key or $box |
+ * | declarations for encrypt'ing. |
+ * | |
+ * | foreach ($ciphertext) { |
+ * | $in = $block_size of $ciphertext; |
+ * | |
+ * | INSERT PHP CODE OF: |
+ * | $cipher_code['encrypt_block']; // encrypt's (string) $in, which is always: |
+ * | // strlen($in) == $this->block_size |
+ * | // here comes the cipher algorithm in action |
+ * | // for encryption. |
+ * | // $cipher_code['encrypt_block'] has to |
+ * | // encrypt the content of the $in variable |
+ * | |
+ * | $plaintext .= $in; |
+ * | } |
+ * | return $plaintext; |
+ * | |
+ * | case 'decrypt': |
+ * | INSERT PHP CODE OF: |
+ * | $cipher_code['init_decrypt']; // decrypt sepcific init code |
+ * | ie: specified $key or $box |
+ * | declarations for decrypt'ing. |
+ * | foreach ($plaintext) { |
+ * | $in = $block_size of $plaintext; |
+ * | |
+ * | INSERT PHP CODE OF: |
+ * | $cipher_code['decrypt_block']; // decrypt's (string) $in, which is always |
+ * | // strlen($in) == $this->block_size |
+ * | // here comes the cipher algorithm in action |
+ * | // for decryption. |
+ * | // $cipher_code['decrypt_block'] has to |
+ * | // decrypt the content of the $in variable |
+ * | $ciphertext .= $in; |
+ * | } |
+ * | return $ciphertext; |
+ * | } |
+ * | } |
+ * +----------------------------------------------------------------------------------------------+
+ * </code>
+ *
+ * See also the Crypt_*::_setupInlineCrypt()'s for
+ * productive inline $cipher_code's how they works.
+ *
+ * Structure of:
+ * <code>
+ * $cipher_code = array(
+ * 'init_crypt' => (string) '', // optional
+ * 'init_encrypt' => (string) '', // optional
+ * 'init_decrypt' => (string) '', // optional
+ * 'encrypt_block' => (string) '', // required
+ * 'decrypt_block' => (string) '' // required
+ * );
+ * </code>
+ *
+ * @see Crypt_Base::_setupInlineCrypt()
+ * @see Crypt_Base::encrypt()
+ * @see Crypt_Base::decrypt()
+ * @param Array $cipher_code
+ * @access private
+ * @return String (the name of the created callback function)
+ */
+ function _createInlineCryptFunction($cipher_code)
+ {
+ $block_size = $this->block_size;
+
+ // optional
+ $init_crypt = isset($cipher_code['init_crypt']) ? $cipher_code['init_crypt'] : '';
+ $init_encrypt = isset($cipher_code['init_encrypt']) ? $cipher_code['init_encrypt'] : '';
+ $init_decrypt = isset($cipher_code['init_decrypt']) ? $cipher_code['init_decrypt'] : '';
+ // required
+ $encrypt_block = $cipher_code['encrypt_block'];
+ $decrypt_block = $cipher_code['decrypt_block'];
+
+ // Generating mode of operation inline code,
+ // merged with the $cipher_code algorithm
+ // for encrypt- and decryption.
+ switch ($this->mode) {
+ case CRYPT_MODE_ECB:
+ $encrypt = $init_encrypt . '
+ $_ciphertext = "";
+ $_text = $self->_pad($_text);
+ $_plaintext_len = strlen($_text);
+
+ for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') {
+ $in = substr($_text, $_i, '.$block_size.');
+ '.$encrypt_block.'
+ $_ciphertext.= $in;
+ }
+
+ return $_ciphertext;
+ ';
+
+ $decrypt = $init_decrypt . '
+ $_plaintext = "";
+ $_text = str_pad($_text, strlen($_text) + ('.$block_size.' - strlen($_text) % '.$block_size.') % '.$block_size.', chr(0));
+ $_ciphertext_len = strlen($_text);
+
+ for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') {
+ $in = substr($_text, $_i, '.$block_size.');
+ '.$decrypt_block.'
+ $_plaintext.= $in;
+ }
+
+ return $self->_unpad($_plaintext);
+ ';
+ break;
+ case CRYPT_MODE_CTR:
+ $encrypt = $init_encrypt . '
+ $_ciphertext = "";
+ $_plaintext_len = strlen($_text);
+ $_xor = $self->encryptIV;
+ $_buffer = &$self->enbuffer;
+
+ if (strlen($_buffer["encrypted"])) {
+ for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') {
+ $_block = substr($_text, $_i, '.$block_size.');
+ if (strlen($_block) > strlen($_buffer["encrypted"])) {
+ $in = $self->_generateXor($_xor, '.$block_size.');
+ '.$encrypt_block.'
+ $_buffer["encrypted"].= $in;
+ }
+ $_key = $self->_stringShift($_buffer["encrypted"], '.$block_size.');
+ $_ciphertext.= $_block ^ $_key;
+ }
+ } else {
+ for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') {
+ $_block = substr($_text, $_i, '.$block_size.');
+ $in = $self->_generateXor($_xor, '.$block_size.');
+ '.$encrypt_block.'
+ $_key = $in;
+ $_ciphertext.= $_block ^ $_key;
+ }
+ }
+ if ($self->continuousBuffer) {
+ $self->encryptIV = $_xor;
+ if ($_start = $_plaintext_len % '.$block_size.') {
+ $_buffer["encrypted"] = substr($_key, $_start) . $_buffer["encrypted"];
+ }
+ }
+
+ return $_ciphertext;
+ ';
+
+ $decrypt = $init_encrypt . '
+ $_plaintext = "";
+ $_ciphertext_len = strlen($_text);
+ $_xor = $self->decryptIV;
+ $_buffer = &$self->debuffer;
+
+ if (strlen($_buffer["ciphertext"])) {
+ for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') {
+ $_block = substr($_text, $_i, '.$block_size.');
+ if (strlen($_block) > strlen($_buffer["ciphertext"])) {
+ $in = $self->_generateXor($_xor, '.$block_size.');
+ '.$encrypt_block.'
+ $_buffer["ciphertext"].= $in;
+ }
+ $_key = $self->_stringShift($_buffer["ciphertext"], '.$block_size.');
+ $_plaintext.= $_block ^ $_key;
+ }
+ } else {
+ for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') {
+ $_block = substr($_text, $_i, '.$block_size.');
+ $in = $self->_generateXor($_xor, '.$block_size.');
+ '.$encrypt_block.'
+ $_key = $in;
+ $_plaintext.= $_block ^ $_key;
+ }
+ }
+ if ($self->continuousBuffer) {
+ $self->decryptIV = $_xor;
+ if ($_start = $_ciphertext_len % '.$block_size.') {
+ $_buffer["ciphertext"] = substr($_key, $_start) . $_buffer["ciphertext"];
+ }
+ }
+
+ return $_plaintext;
+ ';
+ break;
+ case CRYPT_MODE_CFB:
+ $encrypt = $init_encrypt . '
+ $_ciphertext = "";
+ $_buffer = &$self->enbuffer;
+
+ if ($self->continuousBuffer) {
+ $_iv = &$self->encryptIV;
+ $_pos = &$_buffer["pos"];
+ } else {
+ $_iv = $self->encryptIV;
+ $_pos = 0;
+ }
+ $_len = strlen($_text);
+ $_i = 0;
+ if ($_pos) {
+ $_orig_pos = $_pos;
+ $_max = '.$block_size.' - $_pos;
+ if ($_len >= $_max) {
+ $_i = $_max;
+ $_len-= $_max;
+ $_pos = 0;
+ } else {
+ $_i = $_len;
+ $_pos+= $_len;
+ $_len = 0;
+ }
+ $_ciphertext = substr($_iv, $_orig_pos) ^ $_text;
+ $_iv = substr_replace($_iv, $_ciphertext, $_orig_pos, $_i);
+ }
+ while ($_len >= '.$block_size.') {
+ $in = $_iv;
+ '.$encrypt_block.';
+ $_iv = $in ^ substr($_text, $_i, '.$block_size.');
+ $_ciphertext.= $_iv;
+ $_len-= '.$block_size.';
+ $_i+= '.$block_size.';
+ }
+ if ($_len) {
+ $in = $_iv;
+ '.$encrypt_block.'
+ $_iv = $in;
+ $_block = $_iv ^ substr($_text, $_i);
+ $_iv = substr_replace($_iv, $_block, 0, $_len);
+ $_ciphertext.= $_block;
+ $_pos = $_len;
+ }
+ return $_ciphertext;
+ ';
+
+ $decrypt = $init_encrypt . '
+ $_plaintext = "";
+ $_buffer = &$self->debuffer;
+
+ if ($self->continuousBuffer) {
+ $_iv = &$self->decryptIV;
+ $_pos = &$_buffer["pos"];
+ } else {
+ $_iv = $self->decryptIV;
+ $_pos = 0;
+ }
+ $_len = strlen($_text);
+ $_i = 0;
+ if ($_pos) {
+ $_orig_pos = $_pos;
+ $_max = '.$block_size.' - $_pos;
+ if ($_len >= $_max) {
+ $_i = $_max;
+ $_len-= $_max;
+ $_pos = 0;
+ } else {
+ $_i = $_len;
+ $_pos+= $_len;
+ $_len = 0;
+ }
+ $_plaintext = substr($_iv, $_orig_pos) ^ $_text;
+ $_iv = substr_replace($_iv, substr($_text, 0, $_i), $_orig_pos, $_i);
+ }
+ while ($_len >= '.$block_size.') {
+ $in = $_iv;
+ '.$encrypt_block.'
+ $_iv = $in;
+ $cb = substr($_text, $_i, '.$block_size.');
+ $_plaintext.= $_iv ^ $cb;
+ $_iv = $cb;
+ $_len-= '.$block_size.';
+ $_i+= '.$block_size.';
+ }
+ if ($_len) {
+ $in = $_iv;
+ '.$encrypt_block.'
+ $_iv = $in;
+ $_plaintext.= $_iv ^ substr($_text, $_i);
+ $_iv = substr_replace($_iv, substr($_text, $_i), 0, $_len);
+ $_pos = $_len;
+ }
+
+ return $_plaintext;
+ ';
+ break;
+ case CRYPT_MODE_OFB:
+ $encrypt = $init_encrypt . '
+ $_ciphertext = "";
+ $_plaintext_len = strlen($_text);
+ $_xor = $self->encryptIV;
+ $_buffer = &$self->enbuffer;
+
+ if (strlen($_buffer["xor"])) {
+ for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') {
+ $_block = substr($_text, $_i, '.$block_size.');
+ if (strlen($_block) > strlen($_buffer["xor"])) {
+ $in = $_xor;
+ '.$encrypt_block.'
+ $_xor = $in;
+ $_buffer["xor"].= $_xor;
+ }
+ $_key = $self->_stringShift($_buffer["xor"], '.$block_size.');
+ $_ciphertext.= $_block ^ $_key;
+ }
+ } else {
+ for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') {
+ $in = $_xor;
+ '.$encrypt_block.'
+ $_xor = $in;
+ $_ciphertext.= substr($_text, $_i, '.$block_size.') ^ $_xor;
+ }
+ $_key = $_xor;
+ }
+ if ($self->continuousBuffer) {
+ $self->encryptIV = $_xor;
+ if ($_start = $_plaintext_len % '.$block_size.') {
+ $_buffer["xor"] = substr($_key, $_start) . $_buffer["xor"];
+ }
+ }
+ return $_ciphertext;
+ ';
+
+ $decrypt = $init_encrypt . '
+ $_plaintext = "";
+ $_ciphertext_len = strlen($_text);
+ $_xor = $self->decryptIV;
+ $_buffer = &$self->debuffer;
+
+ if (strlen($_buffer["xor"])) {
+ for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') {
+ $_block = substr($_text, $_i, '.$block_size.');
+ if (strlen($_block) > strlen($_buffer["xor"])) {
+ $in = $_xor;
+ '.$encrypt_block.'
+ $_xor = $in;
+ $_buffer["xor"].= $_xor;
+ }
+ $_key = $self->_stringShift($_buffer["xor"], '.$block_size.');
+ $_plaintext.= $_block ^ $_key;
+ }
+ } else {
+ for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') {
+ $in = $_xor;
+ '.$encrypt_block.'
+ $_xor = $in;
+ $_plaintext.= substr($_text, $_i, '.$block_size.') ^ $_xor;
+ }
+ $_key = $_xor;
+ }
+ if ($self->continuousBuffer) {
+ $self->decryptIV = $_xor;
+ if ($_start = $_ciphertext_len % '.$block_size.') {
+ $_buffer["xor"] = substr($_key, $_start) . $_buffer["xor"];
+ }
+ }
+ return $_plaintext;
+ ';
+ break;
+ case CRYPT_MODE_STREAM:
+ $encrypt = $init_encrypt . '
+ $_ciphertext = "";
+ '.$encrypt_block.'
+ return $_ciphertext;
+ ';
+ $decrypt = $init_decrypt . '
+ $_plaintext = "";
+ '.$decrypt_block.'
+ return $_plaintext;
+ ';
+ break;
+ // case CRYPT_MODE_CBC:
+ default:
+ $encrypt = $init_encrypt . '
+ $_ciphertext = "";
+ $_text = $self->_pad($_text);
+ $_plaintext_len = strlen($_text);
+
+ $in = $self->encryptIV;
+
+ for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') {
+ $in = substr($_text, $_i, '.$block_size.') ^ $in;
+ '.$encrypt_block.'
+ $_ciphertext.= $in;
+ }
+
+ if ($self->continuousBuffer) {
+ $self->encryptIV = $in;
+ }
+
+ return $_ciphertext;
+ ';
+
+ $decrypt = $init_decrypt . '
+ $_plaintext = "";
+ $_text = str_pad($_text, strlen($_text) + ('.$block_size.' - strlen($_text) % '.$block_size.') % '.$block_size.', chr(0));
+ $_ciphertext_len = strlen($_text);
+
+ $_iv = $self->decryptIV;
+
+ for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') {
+ $in = $_block = substr($_text, $_i, '.$block_size.');
+ '.$decrypt_block.'
+ $_plaintext.= $in ^ $_iv;
+ $_iv = $_block;
+ }
+
+ if ($self->continuousBuffer) {
+ $self->decryptIV = $_iv;
+ }
+
+ return $self->_unpad($_plaintext);
+ ';
+ break;
+ }
+
+ // Create the $inline function and return its name as string. Ready to run!
+ return create_function('$_action, &$self, $_text', $init_crypt . 'if ($_action == "encrypt") { ' . $encrypt . ' } else { ' . $decrypt . ' }');
+ }
+
+ /**
+ * Holds the lambda_functions table (classwide)
+ *
+ * Each name of the lambda function, created from
+ * _setupInlineCrypt() && _createInlineCryptFunction()
+ * is stored, classwide (!), here for reusing.
+ *
+ * The string-based index of $function is a classwide
+ * uniqe value representing, at least, the $mode of
+ * operation (or more... depends of the optimizing level)
+ * for which $mode the lambda function was created.
+ *
+ * @access private
+ * @return &Array
+ */
+ function &_getLambdaFunctions()
+ {
+ static $functions = array();
+ return $functions;
+ }
+}
projects / friendica-addons.git / blobdiff