<?php
/**
* RC4 aka CipherSaber (1 and 2) encryption and decryption with base64 encoding
* For more info on CS algorithm go to http://ciphersaber.gurus.com/
* Based on Ian Gulliver script posted on http://www.xs4all.nl/~cg/ciphersaber/
* (I bet that guy is a PERL guru, but doesn't understand PHP at all)
*
* © 2002-2003 by Emilis Dambauskas under Artistic license (open-source)
*
* @access public
* @author Emilis Dambauskas * emilis@gildija.lt * ICQ#70382138 * www.emilis.tk
* @created 2003-04-03 01:09
* @modified 2003-04-03 23:22
* @version 1.2 (fixed a bug in binEncrypt and fixed code that emmitted
* warnings in method _cs, thanks alot to Dallas Pool and Peter Kelly)
* @package Cheap Tricks Library
*
* $Id: ctl.CipherSaber.class.php,v 1.0 2003/04/03 02:01:00 lunaticlt Exp $
**/
/**
* Methods:
* ctlCipherSaber($csl=1) : constructor (also sets CS2 N if needed)
* encrypt($str, $key) : encrypts string with key and base64
* decrypt($str, $key) : decrypts base64 string with key
* binEncrypt($str, $key) : encrypts string without base64
* binDecrypt($str, $key) : decrypts string without base64
* setCsLength($length) : sets CS2 N
* getCsLength($length) : returns CS2 N
*
* Example:
* $ccs = &new ctlCipherSaber();
* // should produce 'U1w'Kn':
* echo $ccs->binDecrypt('1234567890abcdef', 'xyz');
**/
class ctlCipherSaber
{
var $r; // random number or 10byte key
var $csl; // (CSL) CS N length for CS2
/**
* Constructor
*
* @access public
* @param CipherSaber2 length (defaults to 1 == CS1)
**/
function ctlCipherSaber($csl = 1) // defaults to CS1
{
$this->csl = $csl;
}
/**
* set CS2 length
*
* @access public
* @param $length - integer length value
**/
function setCsLength($length)
{
$this->csl = $length;
}
/**
* get CS2 length
*
* @access public
* @return integer length value
**/
function getCsLength()
{
return $this->csl;
}
/**
* Usual string encrypt with additional base64 encryption
*
* @access public
* @param $str - string to be encrypted
* @param $key - key/password to be used for encryption
* @return encrypted and base64 encoded string
**/
function encrypt($str, $key)
{
srand((double)microtime()*1234567);
$this->r = substr(md5(rand(0,32000)),0,10);
return base64_encode($this->r.$this->_cs($str,$key));
}
/**
* Usual base64 string decrypt
*
* @access public
* @param $str - string (base64 encoded) to be decrypted
* @param $key - key/password to be used for decryption
* @return decrypted string
**/
function decrypt($str, $key)
{
$str=base64_decode($str);
$this->r = substr($str,0,10);
$str=substr($str,10);
return $this->_cs($str, $key);
}
/**
* Encrypt without base64
*
* @access public
* @param $str - string to be encrypted
* @param $key - key/password to be used for encryption
* @return encrypted string
**/
function binEncrypt($str,$key)
{
srand((double)microtime()*1234567);
$this->r = substr(md5(rand(0,32000)),0,10);
return $this->r.$this->_cs($str,$key);
}
/**
* Decrypt without base64
*
* @access public
* @param $str - string to be decrypted
* @param $key - key/password to be used for decryption
* @return decrypted string
**/
function binDecrypt($str,$key)
{
$this->r = substr($str,0,10);
$str=substr($str,10);
return $this->_cs($str,$key);
}
/**
* CipherSaber algorithm
*
* @access private
* @param $d - string
* @param $p - key
* @return encrypted/decrypted string
**/
function _cs($d, $p)
{
$k = $this->r;
$p .= $k;
for ($i=0; $i < 256; $i++)
$S[$i] = $i;
$j = 0;
$t = strlen($p);
for ($i=0; $i < 256; $i++)
{
$K[$i] = ord(substr($p,$j,1));
$j = ($j + 1) % $t;
}
$j=0;
for ($kk=0; $kk < $this->csl; $kk++) // this loop gives CS2 functionality
{
for ($i = 0; $i < 256; $i++)
{
$j = ($j + $S[$i] + $K[$i]) & 0xff;
$t = $S[$i];
$S[$i] = $S[$j];
$S[$j] = $t;
}
}
$i=0;
$j=0;
$ii=0;
$ret = '';
$dlen = strlen($d);
for ($ii=0; $ii < $dlen; $ii++)
{
$c=$d{$ii};
$i = ($i + 1) & 0xff;
$j = ($j + $S[$i]) & 0xff;
$t = $S[$i];
$S[$i] = $S[$j];
$S[$j] = $t;
$t = ($S[$i] + $S[$j]) & 0xff;
$ret .= chr($S[$t]) ^ $c;
}
return $ret;
}
}
?>
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