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<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
* CodeIgniter
*
* An open source application development framework for PHP 4.3.2 or newer
*
* @package CodeIgniter
* @author ExpressionEngine Dev Team
* @copyright Copyright (c) 2008 - 2009, EllisLab, Inc.
* @license http://codeigniter.com/user_guide/license.html
* @link http://codeigniter.com
* @since Version 1.0
* @filesource
*/
// ------------------------------------------------------------------------
/**
* SHA1 Encoding Class
*
* Purpose: Provides 160 bit hashing using The Secure Hash Algorithm
* developed at the National Institute of Standards and Technology. The 40
* character SHA1 message hash is computationally infeasible to crack.
*
* This class is a fallback for servers that are not running PHP greater than
* 4.3, or do not have the MHASH library.
*
* This class is based on two scripts:
*
* Marcus Campbell's PHP implementation (GNU license)
* http://www.tecknik.net/sha-1/
*
* ...which is based on Paul Johnston's JavaScript version
* (BSD license). http://pajhome.org.uk/
*
* I encapsulated the functions and wrote one additional method to fix
* a hex conversion bug. - Rick Ellis
*
* @package CodeIgniter
* @subpackage Libraries
* @category Encryption
* @author ExpressionEngine Dev Team
* @link http://codeigniter.com/user_guide/general/encryption.html
*/
class CI_SHA {
function CI_SHA()
{
log_message('debug', "SHA1 Class Initialized");
}
/**
* Generate the Hash
*
* @access public
* @param string
* @return string
*/
function generate($str)
{
$n = ((strlen($str) + 8) >> 6) + 1;
for ($i = 0; $i < $n * 16; $i++)
{
$x[$i] = 0;
}
for ($i = 0; $i < strlen($str); $i++)
{
$x[$i >> 2] |= ord(substr($str, $i, 1)) << (24 - ($i % 4) * 8);
}
$x[$i >> 2] |= 0x80 << (24 - ($i % 4) * 8);
$x[$n * 16 - 1] = strlen($str) * 8;
$a = 1732584193;
$b = -271733879;
$c = -1732584194;
$d = 271733878;
$e = -1009589776;
for ($i = 0; $i < count($x); $i += 16)
{
$olda = $a;
$oldb = $b;
$oldc = $c;
$oldd = $d;
$olde = $e;
for($j = 0; $j < 80; $j++)
{
if ($j < 16)
{
$w[$j] = $x[$i + $j];
}
else
{
$w[$j] = $this->_rol($w[$j - 3] ^ $w[$j - 8] ^ $w[$j - 14] ^ $w[$j - 16], 1);
}
$t = $this->_safe_add($this->_safe_add($this->_rol($a, 5), $this->_ft($j, $b, $c, $d)), $this->_safe_add($this->_safe_add($e, $w[$j]), $this->_kt($j)));
$e = $d;
$d = $c;
$c = $this->_rol($b, 30);
$b = $a;
$a = $t;
}
$a = $this->_safe_add($a, $olda);
$b = $this->_safe_add($b, $oldb);
$c = $this->_safe_add($c, $oldc);
$d = $this->_safe_add($d, $oldd);
$e = $this->_safe_add($e, $olde);
}
return $this->_hex($a).$this->_hex($b).$this->_hex($c).$this->_hex($d).$this->_hex($e);
}
// --------------------------------------------------------------------
/**
* Convert a decimal to hex
*
* @access private
* @param string
* @return string
*/
function _hex($str)
{
$str = dechex($str);
if (strlen($str) == 7)
{
$str = '0'.$str;
}
return $str;
}
// --------------------------------------------------------------------
/**
* Return result based on iteration
*
* @access private
* @return string
*/
function _ft($t, $b, $c, $d)
{
if ($t < 20)
return ($b & $c) | ((~$b) & $d);
if ($t < 40)
return $b ^ $c ^ $d;
if ($t < 60)
return ($b & $c) | ($b & $d) | ($c & $d);
return $b ^ $c ^ $d;
}
// --------------------------------------------------------------------
/**
* Determine the additive constant
*
* @access private
* @return string
*/
function _kt($t)
{
if ($t < 20)
{
return 1518500249;
}
else if ($t < 40)
{
return 1859775393;
}
else if ($t < 60)
{
return -1894007588;
}
else
{
return -899497514;
}
}
// --------------------------------------------------------------------
/**
* Add integers, wrapping at 2^32
*
* @access private
* @return string
*/
function _safe_add($x, $y)
{
$lsw = ($x & 0xFFFF) + ($y & 0xFFFF);
$msw = ($x >> 16) + ($y >> 16) + ($lsw >> 16);
return ($msw << 16) | ($lsw & 0xFFFF);
}
// --------------------------------------------------------------------
/**
* Bitwise rotate a 32-bit number
*
* @access private
* @return integer
*/
function _rol($num, $cnt)
{
return ($num << $cnt) | $this->_zero_fill($num, 32 - $cnt);
}
// --------------------------------------------------------------------
/**
* Pad string with zero
*
* @access private
* @return string
*/
function _zero_fill($a, $b)
{
$bin = decbin($a);
if (strlen($bin) < $b)
{
$bin = 0;
}
else
{
$bin = substr($bin, 0, strlen($bin) - $b);
}
for ($i=0; $i < $b; $i++)
{
$bin = "0".$bin;
}
return bindec($bin);
}
}
// END CI_SHA
/* End of file Sha1.php */
/* Location: ./system/libraries/Sha1.php */
