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Diffstat (limited to 'system/libraries/Sha1.php')
| -rw-r--r-- | system/libraries/Sha1.php | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/system/libraries/Sha1.php b/system/libraries/Sha1.php new file mode 100644 index 000000000..13196eb69 --- /dev/null +++ b/system/libraries/Sha1.php @@ -0,0 +1,254 @@ +<?php if (!defined('BASEPATH')) exit('No direct script access allowed'); +/** + * Code Igniter + * + * An open source application development framework for PHP 4.3.2 or newer + * + * @package CodeIgniter + * @author Rick Ellis + * @copyright Copyright (c) 2006, pMachine, Inc. + * @license http://www.codeignitor.com/user_guide/license.html + * @link http://www.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 Rick Ellis + * @link http://www.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; $i < sizeof($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); + } + // END generate() + + // -------------------------------------------------------------------- + + /** + * 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 $str; + } + // END _hex() + + // -------------------------------------------------------------------- + + /** + * Return result based on iteration + * + * @access private + * @return string + */ + function _ft($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 ^ $d; + } + // END _ft() + + // -------------------------------------------------------------------- + + /** + * Determine the additive constant + * + * @access private + * @return string + */ + function _kt($t) + { + if ($t < 20) + { + return 1518500249; + } + else if ($t < 40) + { + return 1859775393; + } + else if ($t < 60) + { + return -1894007588; + } + else + { + return -899497514; + } + } + // END _kt() + + // -------------------------------------------------------------------- + + /** + * Add integers, wrapping at 2^32 + * + * @access private + * @return string + */ + function _safe_add($x, $y) + { + $lsw = ($x & 0xFFFF) + ($y & 0xFFFF); + $msw = ($x >> 16) + ($y >> 16) + ($lsw >> 16); + + return ($msw << 16) | ($lsw & 0xFFFF); + } + // END _safe_add() + + // -------------------------------------------------------------------- + + /** + * 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 +?>
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