1 <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
5 * An open source application development framework for PHP 5.1.6 or newer
8 * @author ExpressionEngine Dev Team
9 * @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
10 * @license http://codeigniter.com/user_guide/license.html
11 * @link http://codeigniter.com
16 // ------------------------------------------------------------------------
21 * Purpose: Provides 160 bit hashing using The Secure Hash Algorithm
22 * developed at the National Institute of Standards and Technology. The 40
23 * character SHA1 message hash is computationally infeasible to crack.
25 * This class is a fallback for servers that are not running PHP greater than
26 * 4.3, or do not have the MHASH library.
28 * This class is based on two scripts:
30 * Marcus Campbell's PHP implementation (GNU license)
31 * http://www.tecknik.net/sha-1/
33 * ...which is based on Paul Johnston's JavaScript version
34 * (BSD license). http://pajhome.org.uk/
36 * I encapsulated the functions and wrote one additional method to fix
37 * a hex conversion bug. - Rick Ellis
39 * @package CodeIgniter
40 * @subpackage Libraries
41 * @category Encryption
42 * @author ExpressionEngine Dev Team
43 * @link http://codeigniter.com/user_guide/general/encryption.html
47 public function __construct()
49 log_message('debug', "SHA1 Class Initialized");
59 function generate($str)
61 $n = ((strlen($str) + 8) >> 6) + 1;
63 for ($i = 0; $i < $n * 16; $i++)
68 for ($i = 0; $i < strlen($str); $i++)
70 $x[$i >> 2] |= ord(substr($str, $i, 1)) << (24 - ($i % 4) * 8);
73 $x[$i >> 2] |= 0x80 << (24 - ($i % 4) * 8);
75 $x[$n * 16 - 1] = strlen($str) * 8;
83 for ($i = 0; $i < count($x); $i += 16)
91 for ($j = 0; $j < 80; $j++)
99 $w[$j] = $this->_rol($w[$j - 3] ^ $w[$j - 8] ^ $w[$j - 14] ^ $w[$j - 16], 1);
102 $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)));
106 $c = $this->_rol($b, 30);
111 $a = $this->_safe_add($a, $olda);
112 $b = $this->_safe_add($b, $oldb);
113 $c = $this->_safe_add($c, $oldc);
114 $d = $this->_safe_add($d, $oldd);
115 $e = $this->_safe_add($e, $olde);
118 return $this->_hex($a).$this->_hex($b).$this->_hex($c).$this->_hex($d).$this->_hex($e);
121 // --------------------------------------------------------------------
124 * Convert a decimal to hex
134 if (strlen($str) == 7)
142 // --------------------------------------------------------------------
145 * Return result based on iteration
150 function _ft($t, $b, $c, $d)
153 return ($b & $c) | ((~$b) & $d);
157 return ($b & $c) | ($b & $d) | ($c & $d);
162 // --------------------------------------------------------------------
165 * Determine the additive constant
190 // --------------------------------------------------------------------
193 * Add integers, wrapping at 2^32
198 function _safe_add($x, $y)
200 $lsw = ($x & 0xFFFF) + ($y & 0xFFFF);
201 $msw = ($x >> 16) + ($y >> 16) + ($lsw >> 16);
203 return ($msw << 16) | ($lsw & 0xFFFF);
206 // --------------------------------------------------------------------
209 * Bitwise rotate a 32-bit number
214 function _rol($num, $cnt)
216 return ($num << $cnt) | $this->_zero_fill($num, 32 - $cnt);
219 // --------------------------------------------------------------------
222 * Pad string with zero
227 function _zero_fill($a, $b)
231 if (strlen($bin) < $b)
237 $bin = substr($bin, 0, strlen($bin) - $b);
240 for ($i=0; $i < $b; $i++)
250 /* End of file Sha1.php */
251 /* Location: ./system/libraries/Sha1.php */