541 lines
19 KiB
PHP
Executable File
541 lines
19 KiB
PHP
Executable File
<?php
|
|
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
|
|
|
|
/**
|
|
* Pure-PHP implementation of AES.
|
|
*
|
|
* Uses mcrypt, if available, and an internal implementation, otherwise.
|
|
*
|
|
* PHP versions 4 and 5
|
|
*
|
|
* If {@link Crypt_AES::setKeyLength() setKeyLength()} isn't called, it'll be calculated from
|
|
* {@link Crypt_AES::setKey() setKey()}. ie. if the key is 128-bits, the key length will be 128-bits. If it's 136-bits
|
|
* it'll be null-padded to 160-bits and 160 bits will be the key length until {@link Crypt_Rijndael::setKey() setKey()}
|
|
* is called, again, at which point, it'll be recalculated.
|
|
*
|
|
* Since Crypt_AES extends Crypt_Rijndael, some functions are available to be called that, in the context of AES, don't
|
|
* make a whole lot of sense. {@link Crypt_AES::setBlockLength() setBlockLength()}, for instance. Calling that function,
|
|
* however possible, won't do anything (AES has a fixed block length whereas Rijndael has a variable one).
|
|
*
|
|
* Here's a short example of how to use this library:
|
|
* <code>
|
|
* <?php
|
|
* include('Crypt/AES.php');
|
|
*
|
|
* $aes = new Crypt_AES();
|
|
*
|
|
* $aes->setKey('abcdefghijklmnop');
|
|
*
|
|
* $size = 10 * 1024;
|
|
* $plaintext = '';
|
|
* for ($i = 0; $i < $size; $i++) {
|
|
* $plaintext.= 'a';
|
|
* }
|
|
*
|
|
* echo $aes->decrypt($aes->encrypt($plaintext));
|
|
* ?>
|
|
* </code>
|
|
*
|
|
* 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_AES
|
|
* @author Jim Wigginton <terrafrost@php.net>
|
|
* @copyright MMVIII Jim Wigginton
|
|
* @license http://www.opensource.org/licenses/mit-license.html MIT License
|
|
* @link http://phpseclib.sourceforge.net
|
|
*/
|
|
|
|
/**
|
|
* Include Crypt_Rijndael
|
|
*/
|
|
if (!class_exists('Crypt_Rijndael')) {
|
|
require_once 'Rijndael.php';
|
|
}
|
|
|
|
/**#@+
|
|
* @access public
|
|
* @see Crypt_AES::encrypt()
|
|
* @see Crypt_AES::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_AES_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_AES_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_AES_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_AES_MODE_CFB', 3);
|
|
/**
|
|
* Encrypt / decrypt using the Cipher Feedback mode.
|
|
*
|
|
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29
|
|
*/
|
|
define('CRYPT_AES_MODE_OFB', 4);
|
|
/**#@-*/
|
|
|
|
/**#@+
|
|
* @access private
|
|
* @see Crypt_AES::Crypt_AES()
|
|
*/
|
|
/**
|
|
* Toggles the internal implementation
|
|
*/
|
|
define('CRYPT_AES_MODE_INTERNAL', 1);
|
|
/**
|
|
* Toggles the mcrypt implementation
|
|
*/
|
|
define('CRYPT_AES_MODE_MCRYPT', 2);
|
|
/**#@-*/
|
|
|
|
/**
|
|
* Pure-PHP implementation of AES.
|
|
*
|
|
* @author Jim Wigginton <terrafrost@php.net>
|
|
* @version 0.1.0
|
|
* @access public
|
|
* @package Crypt_AES
|
|
*/
|
|
class Crypt_AES extends Crypt_Rijndael {
|
|
/**
|
|
* 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_AES::encrypt()
|
|
* @var String
|
|
* @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_AES::decrypt()
|
|
* @var String
|
|
* @access private
|
|
*/
|
|
var $demcrypt;
|
|
|
|
/**
|
|
* mcrypt resource for CFB mode
|
|
*
|
|
* @see Crypt_AES::encrypt()
|
|
* @see Crypt_AES::decrypt()
|
|
* @var String
|
|
* @access private
|
|
*/
|
|
var $ecb;
|
|
|
|
/**
|
|
* Default Constructor.
|
|
*
|
|
* Determines whether or not the mcrypt extension should be used. $mode should only, at present, be
|
|
* CRYPT_AES_MODE_ECB or CRYPT_AES_MODE_CBC. If not explictly set, CRYPT_AES_MODE_CBC will be used.
|
|
*
|
|
* @param optional Integer $mode
|
|
* @return Crypt_AES
|
|
* @access public
|
|
*/
|
|
function Crypt_AES($mode = CRYPT_AES_MODE_CBC)
|
|
{
|
|
if ( !defined('CRYPT_AES_MODE') ) {
|
|
switch (true) {
|
|
case extension_loaded('mcrypt') && in_array('rijndael-128', mcrypt_list_algorithms()):
|
|
define('CRYPT_AES_MODE', CRYPT_AES_MODE_MCRYPT);
|
|
break;
|
|
default:
|
|
define('CRYPT_AES_MODE', CRYPT_AES_MODE_INTERNAL);
|
|
}
|
|
}
|
|
|
|
switch ( CRYPT_AES_MODE ) {
|
|
case CRYPT_AES_MODE_MCRYPT:
|
|
switch ($mode) {
|
|
case CRYPT_AES_MODE_ECB:
|
|
$this->paddable = true;
|
|
$this->mode = MCRYPT_MODE_ECB;
|
|
break;
|
|
case CRYPT_AES_MODE_CTR:
|
|
// ctr doesn't have a constant associated with it even though it appears to be fairly widely
|
|
// supported. in lieu of knowing just how widely supported it is, i've, for now, opted not to
|
|
// include a compatibility layer. the layer has been implemented but, for now, is commented out.
|
|
$this->mode = 'ctr';
|
|
//$this->mode = in_array('ctr', mcrypt_list_modes()) ? 'ctr' : CRYPT_AES_MODE_CTR;
|
|
break;
|
|
case CRYPT_AES_MODE_CFB:
|
|
$this->mode = 'ncfb';
|
|
break;
|
|
case CRYPT_AES_MODE_OFB:
|
|
$this->mode = MCRYPT_MODE_NOFB;
|
|
break;
|
|
case CRYPT_AES_MODE_CBC:
|
|
default:
|
|
$this->paddable = true;
|
|
$this->mode = MCRYPT_MODE_CBC;
|
|
}
|
|
|
|
break;
|
|
default:
|
|
switch ($mode) {
|
|
case CRYPT_AES_MODE_ECB:
|
|
$this->paddable = true;
|
|
$this->mode = CRYPT_RIJNDAEL_MODE_ECB;
|
|
break;
|
|
case CRYPT_AES_MODE_CTR:
|
|
$this->mode = CRYPT_RIJNDAEL_MODE_CTR;
|
|
break;
|
|
case CRYPT_AES_MODE_CFB:
|
|
$this->mode = CRYPT_RIJNDAEL_MODE_CFB;
|
|
break;
|
|
case CRYPT_AES_MODE_OFB:
|
|
$this->mode = CRYPT_RIJNDAEL_MODE_OFB;
|
|
break;
|
|
case CRYPT_AES_MODE_CBC:
|
|
default:
|
|
$this->paddable = true;
|
|
$this->mode = CRYPT_RIJNDAEL_MODE_CBC;
|
|
}
|
|
}
|
|
|
|
if (CRYPT_AES_MODE == CRYPT_AES_MODE_INTERNAL) {
|
|
parent::Crypt_Rijndael($this->mode);
|
|
}
|
|
|
|
}
|
|
|
|
/**
|
|
* Dummy function
|
|
*
|
|
* Since Crypt_AES extends Crypt_Rijndael, this function is, technically, available, but it doesn't do anything.
|
|
*
|
|
* @access public
|
|
* @param Integer $length
|
|
*/
|
|
function setBlockLength($length)
|
|
{
|
|
return;
|
|
}
|
|
|
|
/**
|
|
* Sets the initialization vector. (optional)
|
|
*
|
|
* SetIV is not required when CRYPT_RIJNDAEL_MODE_ECB is being used. If not explictly set, it'll be assumed
|
|
* to be all zero's.
|
|
*
|
|
* @access public
|
|
* @param String $iv
|
|
*/
|
|
function setIV($iv)
|
|
{
|
|
parent::setIV($iv);
|
|
if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) {
|
|
$this->changed = true;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Encrypts a message.
|
|
*
|
|
* $plaintext will be padded with up to 16 additional bytes. Other AES implementations may or may not pad in the
|
|
* same manner. Other common approaches to padding and the reasons why it's necessary are discussed in the following
|
|
* URL:
|
|
*
|
|
* {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html}
|
|
*
|
|
* An alternative to padding is to, separately, send the length of the file. This is what SSH, in fact, does.
|
|
* strlen($plaintext) will still need to be a multiple of 16, however, arbitrary values can be added to make it that
|
|
* length.
|
|
*
|
|
* @see Crypt_AES::decrypt()
|
|
* @access public
|
|
* @param String $plaintext
|
|
*/
|
|
function encrypt($plaintext)
|
|
{
|
|
if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) {
|
|
$this->_mcryptSetup();
|
|
|
|
// re: http://phpseclib.sourceforge.net/cfb-demo.phps
|
|
// using mcrypt's default handing of CFB the above would output two different things. using phpseclib's
|
|
// rewritten CFB implementation the above outputs the same thing twice.
|
|
if ($this->mode == 'ncfb' && $this->continuousBuffer) {
|
|
$iv = &$this->encryptIV;
|
|
$pos = &$this->enbuffer['pos'];
|
|
$len = strlen($plaintext);
|
|
$ciphertext = '';
|
|
$i = 0;
|
|
if ($pos) {
|
|
$orig_pos = $pos;
|
|
$max = 16 - $pos;
|
|
if ($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 >= 16) {
|
|
if ($this->enbuffer['enmcrypt_init'] === false || $len > 280) {
|
|
if ($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 % 16));
|
|
$iv = substr($ciphertext, -16);
|
|
$len%= 16;
|
|
} else {
|
|
while ($len >= 16) {
|
|
$iv = mcrypt_generic($this->ecb, $iv) ^ substr($plaintext, $i, 16);
|
|
$ciphertext.= $iv;
|
|
$len-= 16;
|
|
$i+= 16;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ($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->iv);
|
|
}
|
|
|
|
return $ciphertext;
|
|
}
|
|
|
|
return parent::encrypt($plaintext);
|
|
}
|
|
|
|
/**
|
|
* Decrypts a message.
|
|
*
|
|
* If strlen($ciphertext) is not a multiple of 16, null bytes will be added to the end of the string until it is.
|
|
*
|
|
* @see Crypt_AES::encrypt()
|
|
* @access public
|
|
* @param String $ciphertext
|
|
*/
|
|
function decrypt($ciphertext)
|
|
{
|
|
if ( CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT ) {
|
|
$this->_mcryptSetup();
|
|
|
|
if ($this->mode == 'ncfb' && $this->continuousBuffer) {
|
|
$iv = &$this->decryptIV;
|
|
$pos = &$this->debuffer['pos'];
|
|
$len = strlen($ciphertext);
|
|
$plaintext = '';
|
|
$i = 0;
|
|
if ($pos) {
|
|
$orig_pos = $pos;
|
|
$max = 16 - $pos;
|
|
if ($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 >= 16) {
|
|
$cb = substr($ciphertext, $i, $len - $len % 16);
|
|
$plaintext.= mcrypt_generic($this->ecb, $iv . $cb) ^ $cb;
|
|
$iv = substr($cb, -16);
|
|
$len%= 16;
|
|
}
|
|
if ($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 http://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) + 15) & 0xFFFFFFF0, chr(0));
|
|
}
|
|
|
|
$plaintext = mdecrypt_generic($this->demcrypt, $ciphertext);
|
|
|
|
if (!$this->continuousBuffer) {
|
|
mcrypt_generic_init($this->demcrypt, $this->key, $this->iv);
|
|
}
|
|
|
|
return $this->paddable ? $this->_unpad($plaintext) : $plaintext;
|
|
}
|
|
|
|
return parent::decrypt($ciphertext);
|
|
}
|
|
|
|
/**
|
|
* Setup mcrypt
|
|
*
|
|
* Validates all the variables.
|
|
*
|
|
* @access private
|
|
*/
|
|
function _mcryptSetup()
|
|
{
|
|
if (!$this->changed) {
|
|
return;
|
|
}
|
|
|
|
if (!$this->explicit_key_length) {
|
|
// this just copied from Crypt_Rijndael::_setup()
|
|
$length = strlen($this->key) >> 2;
|
|
if ($length > 8) {
|
|
$length = 8;
|
|
} else if ($length < 4) {
|
|
$length = 4;
|
|
}
|
|
$this->Nk = $length;
|
|
$this->key_size = $length << 2;
|
|
}
|
|
|
|
switch ($this->Nk) {
|
|
case 4: // 128
|
|
$this->key_size = 16;
|
|
break;
|
|
case 5: // 160
|
|
case 6: // 192
|
|
$this->key_size = 24;
|
|
break;
|
|
case 7: // 224
|
|
case 8: // 256
|
|
$this->key_size = 32;
|
|
}
|
|
|
|
$this->key = str_pad(substr($this->key, 0, $this->key_size), $this->key_size, chr(0));
|
|
$this->encryptIV = $this->decryptIV = $this->iv = str_pad(substr($this->iv, 0, 16), 16, chr(0));
|
|
|
|
if (!isset($this->enmcrypt)) {
|
|
$mode = $this->mode;
|
|
//$mode = $this->mode == CRYPT_AES_MODE_CTR ? MCRYPT_MODE_ECB : $this->mode;
|
|
|
|
$this->demcrypt = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', $mode, '');
|
|
$this->enmcrypt = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', $mode, '');
|
|
|
|
if ($mode == 'ncfb') {
|
|
$this->ecb = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_ECB, '');
|
|
}
|
|
|
|
} // else should mcrypt_generic_deinit be called?
|
|
|
|
mcrypt_generic_init($this->demcrypt, $this->key, $this->iv);
|
|
mcrypt_generic_init($this->enmcrypt, $this->key, $this->iv);
|
|
|
|
if ($this->mode == 'ncfb') {
|
|
mcrypt_generic_init($this->ecb, $this->key, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");
|
|
}
|
|
|
|
$this->changed = false;
|
|
}
|
|
|
|
/**
|
|
* Treat consecutive "packets" as if they are a continuous buffer.
|
|
*
|
|
* The default behavior.
|
|
*
|
|
* @see Crypt_Rijndael::disableContinuousBuffer()
|
|
* @access public
|
|
*/
|
|
function enableContinuousBuffer()
|
|
{
|
|
parent::enableContinuousBuffer();
|
|
|
|
if (CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT) {
|
|
$this->enbuffer['enmcrypt_init'] = true;
|
|
$this->debuffer['demcrypt_init'] = true;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Treat consecutive packets as if they are a discontinuous buffer.
|
|
*
|
|
* The default behavior.
|
|
*
|
|
* @see Crypt_Rijndael::enableContinuousBuffer()
|
|
* @access public
|
|
*/
|
|
function disableContinuousBuffer()
|
|
{
|
|
parent::disableContinuousBuffer();
|
|
|
|
if (CRYPT_AES_MODE == CRYPT_AES_MODE_MCRYPT) {
|
|
mcrypt_generic_init($this->enmcrypt, $this->key, $this->iv);
|
|
mcrypt_generic_init($this->demcrypt, $this->key, $this->iv);
|
|
}
|
|
}
|
|
}
|
|
|
|
// vim: ts=4:sw=4:et:
|
|
// vim6: fdl=1:
|