contact-forms / phpseclib-crypt / Hash.php

Hash.php in Contact Forms by Cimatti 1.3.9, at phpseclib-crypt/Hash.php

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1	<?php
2	/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
3
4	/**
5	* Pure-PHP implementations of keyed-hash message authentication codes (HMACs) and various cryptographic hashing functions.
6	*
7	* Uses hash() or mhash() if available and an internal implementation, otherwise. Currently supports the following:
8	*
9	* md2, md5, md5-96, sha1, sha1-96, sha256, sha384, and sha512
10	*
11	* If {@link Crypt_Hash::setKey() setKey()} is called, {@link Crypt_Hash::hash() hash()} will return the HMAC as opposed to
12	* the hash. If no valid algorithm is provided, sha1 will be used.
13	*
14	* PHP versions 4 and 5
15	*
16	* {@internal The variable names are the same as those in
17	* {@link http://tools.ietf.org/html/rfc2104#section-2 RFC2104}.}}
18	*
19	* Here's a short example of how to use this library:
20	* <code>
21	* <?php
22	* include('Crypt/Hash.php');
23	*
24	* $hash = new Crypt_Hash('sha1');
25	*
26	* $hash->setKey('abcdefg');
27	*
28	* echo base64_encode($hash->hash('abcdefg'));
29	* ?>
30	* </code>
31	*
32	* LICENSE: Permission is hereby granted, free of charge, to any person obtaining a copy
33	* of this software and associated documentation files (the "Software"), to deal
34	* in the Software without restriction, including without limitation the rights
35	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
36	* copies of the Software, and to permit persons to whom the Software is
37	* furnished to do so, subject to the following conditions:
38	*
39	* The above copyright notice and this permission notice shall be included in
40	* all copies or substantial portions of the Software.
41	*
42	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
43	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
44	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
45	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
46	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
47	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
48	* THE SOFTWARE.
49	*
50	* @category Crypt
51	* @package Crypt_Hash
52	* @author Jim Wigginton <terrafrost@php.net>
53	* @copyright MMVII Jim Wigginton
54	* @license http://www.opensource.org/licenses/mit-license.html MIT License
55	* @version $Id: Hash.php,v 1.6 2009/11/23 23:37:07 terrafrost Exp $
56	* @link http://phpseclib.sourceforge.net
57	*/
58
59	/**#@+
60	* @access private
61	* @see Crypt_Hash::Crypt_Hash()
62	*/
63	/**
64	* Toggles the internal implementation
65	*/
66	define('CRYPT_HASH_MODE_INTERNAL', 1);
67	/**
68	* Toggles the mhash() implementation, which has been deprecated on PHP 5.3.0+.
69	*/
70	define('CRYPT_HASH_MODE_MHASH', 2);
71	/**
72	* Toggles the hash() implementation, which works on PHP 5.1.2+.
73	*/
74	define('CRYPT_HASH_MODE_HASH', 3);
75	/*#@-/
76
77	/**
78	* Pure-PHP implementations of keyed-hash message authentication codes (HMACs) and various cryptographic hashing functions.
79	*
80	* @author Jim Wigginton <terrafrost@php.net>
81	* @version 0.1.0
82	* @access public
83	* @package Crypt_Hash
84	*/
85	class Crypt_Hash {
86	/**
87	* Byte-length of compression blocks / key (Internal HMAC)
88	*
89	* @see Crypt_Hash::setAlgorithm()
90	* @var Integer
91	* @access private
92	*/
93	var $b;
94
95	/**
96	* Byte-length of hash output (Internal HMAC)
97	*
98	* @see Crypt_Hash::setHash()
99	* @var Integer
100	* @access private
101	*/
102	var $l = false;
103
104	/**
105	* Hash Algorithm
106	*
107	* @see Crypt_Hash::setHash()
108	* @var String
109	* @access private
110	*/
111	var $hash;
112
113	/**
114	* Key
115	*
116	* @see Crypt_Hash::setKey()
117	* @var String
118	* @access private
119	*/
120	var $key = false;
121
122	/**
123	* Outer XOR (Internal HMAC)
124	*
125	* @see Crypt_Hash::setKey()
126	* @var String
127	* @access private
128	*/
129	var $opad;
130
131	/**
132	* Inner XOR (Internal HMAC)
133	*
134	* @see Crypt_Hash::setKey()
135	* @var String
136	* @access private
137	*/
138	var $ipad;
139
140	/**
141	* Default Constructor.
142	*
143	* @param optional String $hash
144	* @return Crypt_Hash
145	* @access public
146	*/
147	function Crypt_Hash($hash = 'sha1')
148	{
149	if ( !defined('CRYPT_HASH_MODE') ) {
150	switch (true) {
151	case extension_loaded('hash'):
152	define('CRYPT_HASH_MODE', CRYPT_HASH_MODE_HASH);
153	break;
154	case extension_loaded('mhash'):
155	define('CRYPT_HASH_MODE', CRYPT_HASH_MODE_MHASH);
156	break;
157	default:
158	define('CRYPT_HASH_MODE', CRYPT_HASH_MODE_INTERNAL);
159	}
160	}
161
162	$this->setHash($hash);
163	}
164
165	/**
166	* Sets the key for HMACs
167	*
168	* Keys can be of any length.
169	*
170	* @access public
171	* @param String $key
172	*/
173	function setKey($key = false)
174	{
175	$this->key = $key;
176	}
177
178	/**
179	* Sets the hash function.
180	*
181	* @access public
182	* @param String $hash
183	*/
184	function setHash($hash)
185	{
186	$hash = strtolower($hash);
187	switch ($hash) {
188	case 'md5-96':
189	case 'sha1-96':
190	$this->l = 12; // 96 / 8 = 12
191	break;
192	case 'md2':
193	case 'md5':
194	$this->l = 16;
195	break;
196	case 'sha1':
197	$this->l = 20;
198	break;
199	case 'sha256':
200	$this->l = 32;
201	break;
202	case 'sha384':
203	$this->l = 48;
204	break;
205	case 'sha512':
206	$this->l = 64;
207	}
208
209	switch ($hash) {
210	case 'md2':
211	$mode = CRYPT_HASH_MODE == CRYPT_HASH_MODE_HASH && in_array('md2', hash_algos()) ?
212	CRYPT_HASH_MODE_HASH : CRYPT_HASH_MODE_INTERNAL;
213	break;
214	case 'sha384':
215	case 'sha512':
216	$mode = CRYPT_HASH_MODE == CRYPT_HASH_MODE_MHASH ? CRYPT_HASH_MODE_INTERNAL : CRYPT_HASH_MODE;
217	break;
218	default:
219	$mode = CRYPT_HASH_MODE;
220	}
221
222	switch ( $mode ) {
223	case CRYPT_HASH_MODE_MHASH:
224	switch ($hash) {
225	case 'md5':
226	case 'md5-96':
227	$this->hash = MHASH_MD5;
228	break;
229	case 'sha256':
230	$this->hash = MHASH_SHA256;
231	break;
232	case 'sha1':
233	case 'sha1-96':
234	default:
235	$this->hash = MHASH_SHA1;
236	}
237	return;
238	case CRYPT_HASH_MODE_HASH:
239	switch ($hash) {
240	case 'md5':
241	case 'md5-96':
242	$this->hash = 'md5';
243	return;
244	case 'md2':
245	case 'sha256':
246	case 'sha384':
247	case 'sha512':
248	$this->hash = $hash;
249	return;
250	case 'sha1':
251	case 'sha1-96':
252	default:
253	$this->hash = 'sha1';
254	}
255	return;
256	}
257
258	switch ($hash) {
259	case 'md2':
260	$this->b = 16;
261	$this->hash = array($this, '_md2');
262	break;
263	case 'md5':
264	case 'md5-96':
265	$this->b = 64;
266	$this->hash = array($this, '_md5');
267	break;
268	case 'sha256':
269	$this->b = 64;
270	$this->hash = array($this, '_sha256');
271	break;
272	case 'sha384':
273	case 'sha512':
274	$this->b = 128;
275	$this->hash = array($this, '_sha512');
276	break;
277	case 'sha1':
278	case 'sha1-96':
279	default:
280	$this->b = 64;
281	$this->hash = array($this, '_sha1');
282	}
283
284	$this->ipad = str_repeat(chr(0x36), $this->b);
285	$this->opad = str_repeat(chr(0x5C), $this->b);
286	}
287
288	/**
289	* Compute the HMAC.
290	*
291	* @access public
292	* @param String $text
293	* @return String
294	*/
295	function hash($text)
296	{
297	$mode = is_array($this->hash) ? CRYPT_HASH_MODE_INTERNAL : CRYPT_HASH_MODE;
298
299	if (!empty($this->key) \|\| is_string($this->key)) {
300	switch ( $mode ) {
301	case CRYPT_HASH_MODE_MHASH:
302	$output = mhash($this->hash, $text, $this->key);
303	break;
304	case CRYPT_HASH_MODE_HASH:
305	$output = hash_hmac($this->hash, $text, $this->key, true);
306	break;
307	case CRYPT_HASH_MODE_INTERNAL:
308	/* "Applications that use keys longer than B bytes will first hash the key using H and then use the
309	resultant L byte string as the actual key to HMAC."
310
311	-- http://tools.ietf.org/html/rfc2104#section-2 */
312	$key = strlen($this->key) > $this->b ? call_user_func($this->hash, $this->key) : $this->key;
313
314	$key = str_pad($key, $this->b, chr(0)); // step 1
315	$temp = $this->ipad ^ $key; // step 2
316	$temp .= $text; // step 3
317	$temp = call_user_func($this->hash, $temp); // step 4
318	$output = $this->opad ^ $key; // step 5
319	$output.= $temp; // step 6
320	$output = call_user_func($this->hash, $output); // step 7
321	}
322	} else {
323	switch ( $mode ) {
324	case CRYPT_HASH_MODE_MHASH:
325	$output = mhash($this->hash, $text);
326	break;
327	case CRYPT_HASH_MODE_HASH:
328	$output = hash($this->hash, $text, true);
329	break;
330	case CRYPT_HASH_MODE_INTERNAL:
331	$output = call_user_func($this->hash, $text);
332	}
333	}
334
335	return substr($output, 0, $this->l);
336	}
337
338	/**
339	* Returns the hash length (in bytes)
340	*
341	* @access public
342	* @return Integer
343	*/
344	function getLength()
345	{
346	return $this->l;
347	}
348
349	/**
350	* Wrapper for MD5
351	*
352	* @access private
353	* @param String $text
354	*/
355	function _md5($m)
356	{
357	return pack('H*', md5($m));
358	}
359
360	/**
361	* Wrapper for SHA1
362	*
363	* @access private
364	* @param String $text
365	*/
366	function _sha1($m)
367	{
368	return pack('H*', sha1($m));
369	}
370
371	/**
372	* Pure-PHP implementation of MD2
373	*
374	* See {@link http://tools.ietf.org/html/rfc1319 RFC1319}.
375	*
376	* @access private
377	* @param String $text
378	*/
379	function _md2($m)
380	{
381	static $s = array(
382	41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
383	19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
384	76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
385	138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
386	245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
387	148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
388	39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
389	181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
390	150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
391	112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
392	96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
393	85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
394	234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
395	129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
396	8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
397	203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
398	166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
399	31, 26, 219, 153, 141, 51, 159, 17, 131, 20
400	);
401
402	// Step 1. Append Padding Bytes
403	$pad = 16 - (strlen($m) & 0xF);
404	$m.= str_repeat(chr($pad), $pad);
405
406	$length = strlen($m);
407
408	// Step 2. Append Checksum
409	$c = str_repeat(chr(0), 16);
410	$l = chr(0);
411	for ($i = 0; $i < $length; $i+= 16) {
412	for ($j = 0; $j < 16; $j++) {
413	// RFC1319 incorrectly states that C[j] should be set to S[c xor L]
414	//$c[$j] = chr($s[ord($m[$i + $j] ^ $l)]);
415	// per <http://www.rfc-editor.org/errata_search.php?rfc=1319>, however, C[j] should be set to S[c xor L] xor C[j]
416	$c[$j] = chr($s[ord($m[$i + $j] ^ $l)] ^ ord($c[$j]));
417	$l = $c[$j];
418	}
419	}
420	$m.= $c;
421
422	$length+= 16;
423
424	// Step 3. Initialize MD Buffer
425	$x = str_repeat(chr(0), 48);
426
427	// Step 4. Process Message in 16-Byte Blocks
428	for ($i = 0; $i < $length; $i+= 16) {
429	for ($j = 0; $j < 16; $j++) {
430	$x[$j + 16] = $m[$i + $j];
431	$x[$j + 32] = $x[$j + 16] ^ $x[$j];
432	}
433	$t = chr(0);
434	for ($j = 0; $j < 18; $j++) {
435	for ($k = 0; $k < 48; $k++) {
436	$x[$k] = $t = $x[$k] ^ chr($s[ord($t)]);
437	//$t = $x[$k] = $x[$k] ^ chr($s[ord($t)]);
438	}
439	$t = chr(ord($t) + $j);
440	}
441	}
442
443	// Step 5. Output
444	return substr($x, 0, 16);
445	}
446
447	/**
448	* Pure-PHP implementation of SHA256
449	*
450	* See {@link http://en.wikipedia.org/wiki/SHA_hash_functions#SHA-256_.28a_SHA-2_variant.29_pseudocode SHA-256 (a SHA-2 variant) pseudocode - Wikipedia}.
451	*
452	* @access private
453	* @param String $text
454	*/
455	function _sha256($m)
456	{
457	if (extension_loaded('suhosin')) {
458	return pack('H*', sha256($m));
459	}
460
461	// Initialize variables
462	$hash = array(
463	0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
464	);
465	// Initialize table of round constants
466	// (first 32 bits of the fractional parts of the cube roots of the first 64 primes 2..311)
467	static $k = array(
468	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
469	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
470	0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
471	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
472	0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
473	0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
474	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
475	0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
476	);
477
478	// Pre-processing
479	$length = strlen($m);
480	// to round to nearest 56 mod 64, we'll add 64 - (length + (64 - 56)) % 64
481	$m.= str_repeat(chr(0), 64 - (($length + 8) & 0x3F));
482	$m[$length] = chr(0x80);
483	// we don't support hashing strings 512MB long
484	$m.= pack('N2', 0, $length << 3);
485
486	// Process the message in successive 512-bit chunks
487	$chunks = str_split($m, 64);
488	foreach ($chunks as $chunk) {
489	$w = array();
490	for ($i = 0; $i < 16; $i++) {
491	extract(unpack('Ntemp', $this->_string_shift($chunk, 4)));
492	$w[] = $temp;
493	}
494
495	// Extend the sixteen 32-bit words into sixty-four 32-bit words
496	for ($i = 16; $i < 64; $i++) {
497	$s0 = $this->_rightRotate($w[$i - 15], 7) ^
498	$this->_rightRotate($w[$i - 15], 18) ^
499	$this->_rightShift( $w[$i - 15], 3);
500	$s1 = $this->_rightRotate($w[$i - 2], 17) ^
501	$this->_rightRotate($w[$i - 2], 19) ^
502	$this->_rightShift( $w[$i - 2], 10);
503	$w[$i] = $this->_add($w[$i - 16], $s0, $w[$i - 7], $s1);
504
505	}
506
507	// Initialize hash value for this chunk
508	list($a, $b, $c, $d, $e, $f, $g, $h) = $hash;
509
510	// Main loop
511	for ($i = 0; $i < 64; $i++) {
512	$s0 = $this->_rightRotate($a, 2) ^
513	$this->_rightRotate($a, 13) ^
514	$this->_rightRotate($a, 22);
515	$maj = ($a & $b) ^
516	($a & $c) ^
517	($b & $c);
518	$t2 = $this->_add($s0, $maj);
519
520	$s1 = $this->_rightRotate($e, 6) ^
521	$this->_rightRotate($e, 11) ^
522	$this->_rightRotate($e, 25);
523	$ch = ($e & $f) ^
524	($this->_not($e) & $g);
525	$t1 = $this->_add($h, $s1, $ch, $k[$i], $w[$i]);
526
527	$h = $g;
528	$g = $f;
529	$f = $e;
530	$e = $this->_add($d, $t1);
531	$d = $c;
532	$c = $b;
533	$b = $a;
534	$a = $this->_add($t1, $t2);
535	}
536
537	// Add this chunk's hash to result so far
538	$hash = array(
539	$this->_add($hash[0], $a),
540	$this->_add($hash[1], $b),
541	$this->_add($hash[2], $c),
542	$this->_add($hash[3], $d),
543	$this->_add($hash[4], $e),
544	$this->_add($hash[5], $f),
545	$this->_add($hash[6], $g),
546	$this->_add($hash[7], $h)
547	);
548	}
549
550	// Produce the final hash value (big-endian)
551	return pack('N8', $hash[0], $hash[1], $hash[2], $hash[3], $hash[4], $hash[5], $hash[6], $hash[7]);
552	}
553
554	/**
555	* Pure-PHP implementation of SHA384 and SHA512
556	*
557	* @access private
558	* @param String $text
559	*/
560	function _sha512($m)
561	{
562	if (!class_exists('Math_BigInteger')) {
563	require_once('Math/BigInteger.php');
564	}
565
566	static $init384, $init512, $k;
567
568	if (!isset($k)) {
569	// Initialize variables
570	$init384 = array( // initial values for SHA384
571	'cbbb9d5dc1059ed8', '629a292a367cd507', '9159015a3070dd17', '152fecd8f70e5939',
572	'67332667ffc00b31', '8eb44a8768581511', 'db0c2e0d64f98fa7', '47b5481dbefa4fa4'
573	);
574	$init512 = array( // initial values for SHA512
575	'6a09e667f3bcc908', 'bb67ae8584caa73b', '3c6ef372fe94f82b', 'a54ff53a5f1d36f1',
576	'510e527fade682d1', '9b05688c2b3e6c1f', '1f83d9abfb41bd6b', '5be0cd19137e2179'
577	);
578
579	for ($i = 0; $i < 8; $i++) {
580	$init384[$i] = new Math_BigInteger($init384[$i], 16);
581	$init384[$i]->setPrecision(64);
582	$init512[$i] = new Math_BigInteger($init512[$i], 16);
583	$init512[$i]->setPrecision(64);
584	}
585
586	// Initialize table of round constants
587	// (first 64 bits of the fractional parts of the cube roots of the first 80 primes 2..409)
588	$k = array(
589	'428a2f98d728ae22', '7137449123ef65cd', 'b5c0fbcfec4d3b2f', 'e9b5dba58189dbbc',
590	'3956c25bf348b538', '59f111f1b605d019', '923f82a4af194f9b', 'ab1c5ed5da6d8118',
591	'd807aa98a3030242', '12835b0145706fbe', '243185be4ee4b28c', '550c7dc3d5ffb4e2',
592	'72be5d74f27b896f', '80deb1fe3b1696b1', '9bdc06a725c71235', 'c19bf174cf692694',
593	'e49b69c19ef14ad2', 'efbe4786384f25e3', '0fc19dc68b8cd5b5', '240ca1cc77ac9c65',
594	'2de92c6f592b0275', '4a7484aa6ea6e483', '5cb0a9dcbd41fbd4', '76f988da831153b5',
595	'983e5152ee66dfab', 'a831c66d2db43210', 'b00327c898fb213f', 'bf597fc7beef0ee4',
596	'c6e00bf33da88fc2', 'd5a79147930aa725', '06ca6351e003826f', '142929670a0e6e70',
597	'27b70a8546d22ffc', '2e1b21385c26c926', '4d2c6dfc5ac42aed', '53380d139d95b3df',
598	'650a73548baf63de', '766a0abb3c77b2a8', '81c2c92e47edaee6', '92722c851482353b',
599	'a2bfe8a14cf10364', 'a81a664bbc423001', 'c24b8b70d0f89791', 'c76c51a30654be30',
600	'd192e819d6ef5218', 'd69906245565a910', 'f40e35855771202a', '106aa07032bbd1b8',
601	'19a4c116b8d2d0c8', '1e376c085141ab53', '2748774cdf8eeb99', '34b0bcb5e19b48a8',
602	'391c0cb3c5c95a63', '4ed8aa4ae3418acb', '5b9cca4f7763e373', '682e6ff3d6b2b8a3',
603	'748f82ee5defb2fc', '78a5636f43172f60', '84c87814a1f0ab72', '8cc702081a6439ec',
604	'90befffa23631e28', 'a4506cebde82bde9', 'bef9a3f7b2c67915', 'c67178f2e372532b',
605	'ca273eceea26619c', 'd186b8c721c0c207', 'eada7dd6cde0eb1e', 'f57d4f7fee6ed178',
606	'06f067aa72176fba', '0a637dc5a2c898a6', '113f9804bef90dae', '1b710b35131c471b',
607	'28db77f523047d84', '32caab7b40c72493', '3c9ebe0a15c9bebc', '431d67c49c100d4c',
608	'4cc5d4becb3e42b6', '597f299cfc657e2a', '5fcb6fab3ad6faec', '6c44198c4a475817'
609	);
610
611	for ($i = 0; $i < 80; $i++) {
612	$k[$i] = new Math_BigInteger($k[$i], 16);
613	}
614	}
615
616	$hash = $this->l == 48 ? $init384 : $init512;
617
618	// Pre-processing
619	$length = strlen($m);
620	// to round to nearest 112 mod 128, we'll add 128 - (length + (128 - 112)) % 128
621	$m.= str_repeat(chr(0), 128 - (($length + 16) & 0x7F));
622	$m[$length] = chr(0x80);
623	// we don't support hashing strings 512MB long
624	$m.= pack('N4', 0, 0, 0, $length << 3);
625
626	// Process the message in successive 1024-bit chunks
627	$chunks = str_split($m, 128);
628	foreach ($chunks as $chunk) {
629	$w = array();
630	for ($i = 0; $i < 16; $i++) {
631	$temp = new Math_BigInteger($this->_string_shift($chunk, 8), 256);
632	$temp->setPrecision(64);
633	$w[] = $temp;
634	}
635
636	// Extend the sixteen 32-bit words into eighty 32-bit words
637	for ($i = 16; $i < 80; $i++) {
638	$temp = array(
639	$w[$i - 15]->bitwise_rightRotate(1),
640	$w[$i - 15]->bitwise_rightRotate(8),
641	$w[$i - 15]->bitwise_rightShift(7)
642	);
643	$s0 = $temp[0]->bitwise_xor($temp[1]);
644	$s0 = $s0->bitwise_xor($temp[2]);
645	$temp = array(
646	$w[$i - 2]->bitwise_rightRotate(19),
647	$w[$i - 2]->bitwise_rightRotate(61),
648	$w[$i - 2]->bitwise_rightShift(6)
649	);
650	$s1 = $temp[0]->bitwise_xor($temp[1]);
651	$s1 = $s1->bitwise_xor($temp[2]);
652	$w[$i] = $w[$i - 16]->copy();
653	$w[$i] = $w[$i]->add($s0);
654	$w[$i] = $w[$i]->add($w[$i - 7]);
655	$w[$i] = $w[$i]->add($s1);
656	}
657
658	// Initialize hash value for this chunk
659	$a = $hash[0]->copy();
660	$b = $hash[1]->copy();
661	$c = $hash[2]->copy();
662	$d = $hash[3]->copy();
663	$e = $hash[4]->copy();
664	$f = $hash[5]->copy();
665	$g = $hash[6]->copy();
666	$h = $hash[7]->copy();
667
668	// Main loop
669	for ($i = 0; $i < 80; $i++) {
670	$temp = array(
671	$a->bitwise_rightRotate(28),
672	$a->bitwise_rightRotate(34),
673	$a->bitwise_rightRotate(39)
674	);
675	$s0 = $temp[0]->bitwise_xor($temp[1]);
676	$s0 = $s0->bitwise_xor($temp[2]);
677	$temp = array(
678	$a->bitwise_and($b),
679	$a->bitwise_and($c),
680	$b->bitwise_and($c)
681	);
682	$maj = $temp[0]->bitwise_xor($temp[1]);
683	$maj = $maj->bitwise_xor($temp[2]);
684	$t2 = $s0->add($maj);
685
686	$temp = array(
687	$e->bitwise_rightRotate(14),
688	$e->bitwise_rightRotate(18),
689	$e->bitwise_rightRotate(41)
690	);
691	$s1 = $temp[0]->bitwise_xor($temp[1]);
692	$s1 = $s1->bitwise_xor($temp[2]);
693	$temp = array(
694	$e->bitwise_and($f),
695	$g->bitwise_and($e->bitwise_not())
696	);
697	$ch = $temp[0]->bitwise_xor($temp[1]);
698	$t1 = $h->add($s1);
699	$t1 = $t1->add($ch);
700	$t1 = $t1->add($k[$i]);
701	$t1 = $t1->add($w[$i]);
702
703	$h = $g->copy();
704	$g = $f->copy();
705	$f = $e->copy();
706	$e = $d->add($t1);
707	$d = $c->copy();
708	$c = $b->copy();
709	$b = $a->copy();
710	$a = $t1->add($t2);
711	}
712
713	// Add this chunk's hash to result so far
714	$hash = array(
715	$hash[0]->add($a),
716	$hash[1]->add($b),
717	$hash[2]->add($c),
718	$hash[3]->add($d),
719	$hash[4]->add($e),
720	$hash[5]->add($f),
721	$hash[6]->add($g),
722	$hash[7]->add($h)
723	);
724	}
725
726	// Produce the final hash value (big-endian)
727	// (Crypt_Hash::hash() trims the output for hashes but not for HMACs. as such, we trim the output here)
728	$temp = $hash[0]->toBytes() . $hash[1]->toBytes() . $hash[2]->toBytes() . $hash[3]->toBytes() .
729	$hash[4]->toBytes() . $hash[5]->toBytes();
730	if ($this->l != 48) {
731	$temp.= $hash[6]->toBytes() . $hash[7]->toBytes();
732	}
733
734	return $temp;
735	}
736
737	/**
738	* Right Rotate
739	*
740	* @access private
741	* @param Integer $int
742	* @param Integer $amt
743	* @see _sha256()
744	* @return Integer
745	*/
746	function _rightRotate($int, $amt)
747	{
748	$invamt = 32 - $amt;
749	$mask = (1 << $invamt) - 1;
750	return (($int << $invamt) & 0xFFFFFFFF) \| (($int >> $amt) & $mask);
751	}
752
753	/**
754	* Right Shift
755	*
756	* @access private
757	* @param Integer $int
758	* @param Integer $amt
759	* @see _sha256()
760	* @return Integer
761	*/
762	function _rightShift($int, $amt)
763	{
764	$mask = (1 << (32 - $amt)) - 1;
765	return ($int >> $amt) & $mask;
766	}
767
768	/**
769	* Not
770	*
771	* @access private
772	* @param Integer $int
773	* @see _sha256()
774	* @return Integer
775	*/
776	function _not($int)
777	{
778	return ~$int & 0xFFFFFFFF;
779	}
780
781	/**
782	* Add
783	*
784	* _sha256() adds multiple unsigned 32-bit integers. Since PHP doesn't support unsigned integers and since the
785	* possibility of overflow exists, care has to be taken. Math_BigInteger() could be used but this should be faster.
786	*
787	* @param String $string
788	* @param optional Integer $index
789	* @return String
790	* @see _sha256()
791	* @access private
792	*/
793	function _add()
794	{
795	static $mod;
796	if (!isset($mod)) {
797	$mod = pow(2, 32);
798	}
799
800	$result = 0;
801	$arguments = func_get_args();
802	foreach ($arguments as $argument) {
803	$result+= $argument < 0 ? ($argument & 0x7FFFFFFF) + 0x80000000 : $argument;
804	}
805
806	return fmod($result, $mod);
807	}
808
809	/**
810	* String Shift
811	*
812	* Inspired by array_shift
813	*
814	* @param String $string
815	* @param optional Integer $index
816	* @return String
817	* @access private
818	*/
819	function _string_shift(&$string, $index = 1)
820	{
821	$substr = substr($string, 0, $index);
822	$string = substr($string, $index);
823	return $substr;
824	}
825	}
826