/wp-content/plugins/updraftplus/includes/phpseclib/Crypt/Base.php
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- <?php
- /* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
- /**
- * 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 MMVII Jim Wigginton
- * @license http://www.opensource.org/licenses/mit-license.html MIT License
- * @version 1.0.1
- * @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
- *
- * @author Jim Wigginton <terrafrost@php.net>
- * @author Hans-Juergen Petrich <petrich@tronic-media.com>
- * @version 1.0.0
- * @access public
- * @package Crypt_Base
- */
- 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 choosen 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 choosen cipher, for example for AES: CRYPT_AES_MODE_ECB or CRYPT_AES_MODE_CBC ...)
- *
- * If not explictly 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 explictly 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}:
- * $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 $method
- * @access public
- */
- function setPassword($password, $method = 'pbkdf2')
- {
- $key = '';
- switch ($method) {
- default: // 'pbkdf2'
- $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
- $dkLen = isset($func_args[5]) ? $func_args[5] : $this->password_key_size;
- // Determining if php[>=5.5.0]'s hash_pbkdf2() function avail- and useable
- switch (true) {
- case !function_exists('hash_pbkdf2'):
- case !function_exists('hash_algos'):
- case !in_array($hash, hash_algos()):
- if (!class_exists('Crypt_Hash')) {
- require_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);
- }
- /**
- * 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 allways 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
- * …
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