<?php
/**
* Wrapper around hash() and hash_hmac() functions supporting truncated hashes
* such as sha256-96. Any hash algorithm returned by hash_algos() (and
* truncated versions thereof) are supported.
*
* If {@link self::setKey() setKey()} is called, {@link self::hash() hash()} will
* return the HMAC as opposed to the hash.
*
* Here's a short example of how to use this library:
* <code>
* <?php
* include 'vendor/autoload.php';
*
* $hash = new \phpseclib\Crypt\Hash('sha512');
*
* $hash->setKey('abcdefg');
*
* echo base64_encode($hash->hash('abcdefg'));
* ?>
* </code>
*
* @category Crypt
* @package Hash
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2015 Jim Wigginton
* @author Andreas Fischer <bantu@phpbb.com>
* @copyright 2015 Andreas Fischer
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://phpseclib.sourceforge.net
*/
namespace phpseclib\Crypt;
use phpseclib\Math\BigInteger;
use phpseclib\Exception\UnsupportedAlgorithmException;
/**
* @package Hash
* @author Jim Wigginton <terrafrost@php.net>
* @author Andreas Fischer <bantu@phpbb.com>
* @access public
*/
class Hash
{
/**
* Hash Parameter
*
* @see self::setHash()
* @var int
* @access private
*/
var $hashParam;
/**
* Byte-length of hash output (Internal HMAC)
*
* @see self::setHash()
* @var int
* @access private
*/
var $length;
/**
* Hash Algorithm
*
* @see self::setHash()
* @var string
* @access private
*/
var $hash;
/**
* Key
*
* @see self::setKey()
* @var string
* @access private
*/
var $key = false;
/**
* Initial Hash
*
* Used only for sha512/*
*
* @see self::_sha512()
* @var array
* @access private
*/
var $initial = false;
/**
* Outer XOR (Internal HMAC)
*
* Used only for sha512/*
*
* @see self::hash()
* @var string
* @access private
*/
var $opad;
/**
* Inner XOR (Internal HMAC)
*
* Used only for sha512/*
*
* @see self::hash()
* @var string
* @access private
*/
var $ipad;
/**
* Default Constructor.
*
* @param string $hash
* @access public
*/
function __construct($hash = 'sha256')
{
$this->setHash($hash);
$this->ipad = str_repeat(chr(0x36), 128);
$this->opad = str_repeat(chr(0x5C), 128);
}
/**
* Sets the key for HMACs
*
* Keys can be of any length.
*
* @access public
* @param string $key
*/
function setKey($key = false)
{
$this->key = $key;
}
/**
* Gets the hash function.
*
* As set by the constructor or by the setHash() method.
*
* @access public
* @return string
*/
function getHash()
{
return $this->hashParam;
}
/**
* Sets the hash function.
*
* @access public
* @param string $hash
*/
function setHash($hash)
{
$this->hashParam = $hash = strtolower($hash);
switch ($hash) {
case 'md2-96':
case 'md5-96':
case 'sha1-96':
case 'sha256-96':
case 'sha512-96':
case 'sha512/224-96':
case 'sha512/256-96':
$hash = substr($hash, 0, -3);
$this->length = 12; // 96 / 8 = 12
break;
case 'md2':
case 'md5':
$this->length = 16;
break;
case 'sha1':
$this->length = 20;
break;
case 'sha224':
case 'sha512/224':
$this->length = 28;
break;
case 'sha256':
case 'sha512/256':
$this->length = 32;
break;
case 'sha384':
$this->length = 48;
break;
case 'sha512':
$this->length = 64;
break;
default:
// see if the hash isn't "officially" supported see if it can
// be "unofficially" supported and calculate the length
// accordingly.
if (in_array($hash, hash_algos())) {
$this->length = strlen(hash($hash, '', true));
break;
}
// if the hash algorithm doens't exist maybe it's a truncated
// hash, e.g. whirlpool-12 or some such.
if (preg_match('#(-\d+)$#', $hash, $matches)) {
$hash = substr($hash, 0, -strlen($matches[1]));
if (in_array($hash, hash_algos())) {
$this->length = abs($matches[1]) >> 3;
break;
}
}
throw new UnsupportedAlgorithmException(
"$hash is not a supported algorithm"
);
}
if ($hash == 'sha512/224' || $hash == 'sha512/256') {
// from http://csrc.nist.gov/publications/fips/fips180-4/fips-180-4.pdf#page=24
$this->initial = $hash == 'sha512/256' ?
array(
'22312194FC2BF72C', '9F555FA3C84C64C2', '2393B86B6F53B151', '963877195940EABD',
'96283EE2A88EFFE3', 'BE5E1E2553863992', '2B0199FC2C85B8AA', '0EB72DDC81C52CA2'
) :
array(
'8C3D37C819544DA2', '73E1996689DCD4D6', '1DFAB7AE32FF9C82', '679DD514582F9FCF',
'0F6D2B697BD44DA8', '77E36F7304C48942', '3F9D85A86A1D36C8', '1112E6AD91D692A1'
);
for ($i = 0; $i < 8; $i++) {
$this->initial[$i] = new BigInteger($this->initial[$i], 16);
$this->initial[$i]->setPrecision(64);
}
}
$this->hash = $hash;
}
/**
* Compute the HMAC.
*
* @access public
* @param string $text
* @return string
*/
function hash($text)
{
switch ($this->hash) {
case 'sha512/224':
case 'sha512/256':
if (empty($this->key) || !is_string($this->key)) {
return substr(self::_sha512($text, $this->initial), 0, $this->length);
}
/* "Applications that use keys longer than B bytes will first hash the key using H and then use the
resultant L byte string as the actual key to HMAC."
-- http://tools.ietf.org/html/rfc2104#section-2 */
$key = strlen($this->key) > $this->b ? self::_sha512($this->key, $this->initial) : $this->key;
$key = str_pad($this->key, 128, chr(0)); // step 1
$temp = $this->ipad ^ $this->key; // step 2
$temp .= $text; // step 3
$temp = self::_sha512($temp, $this->initial); // step 4
$output = $this->opad ^ $this->key; // step 5
$output.= $temp; // step 6
$output = self::_sha512($output, $this->initial); // step 7
return substr($output, 0, $this->length);
}
$output = !empty($this->key) || is_string($this->key) ?
hash_hmac($this->hash, $text, $this->key, true) :
hash($this->hash, $text, true);
return strlen($output) > $this->length
? substr($output, 0, $this->length)
: $output;
}
/**
* Returns the hash length (in bytes)
*
* @access public
* @return int
*/
function getLength()
{
return $this->length;
}
/**
* Pure-PHP implementation of SHA512
*
* @access private
* @param string $m
*/
static function _sha512($m, $hash)
{
static $k;
if (!isset($k)) {
// Initialize table of round constants
// (first 64 bits of the fractional parts of the cube roots of the first 80 primes 2..409)
$k = array(
'428a2f98d728ae22', '7137449123ef65cd', 'b5c0fbcfec4d3b2f', 'e9b5dba58189dbbc',
'3956c25bf348b538', '59f111f1b605d019', '923f82a4af194f9b', 'ab1c5ed5da6d8118',
'd807aa98a3030242', '12835b0145706fbe', '243185be4ee4b28c', '550c7dc3d5ffb4e2',
'72be5d74f27b896f', '80deb1fe3b1696b1', '9bdc06a725c71235', 'c19bf174cf692694',
'e49b69c19ef14ad2', 'efbe4786384f25e3', '0fc19dc68b8cd5b5', '240ca1cc77ac9c65',
'2de92c6f592b0275', '4a7484aa6ea6e483', '5cb0a9dcbd41fbd4', '76f988da831153b5',
'983e5152ee66dfab', 'a831c66d2db43210', 'b00327c898fb213f', 'bf597fc7beef0ee4',
'c6e00bf33da88fc2', 'd5a79147930aa725', '06ca6351e003826f', '142929670a0e6e70',
'27b70a8546d22ffc', '2e1b21385c26c926', '4d2c6dfc5ac42aed', '53380d139d95b3df',
'650a73548baf63de', '766a0abb3c77b2a8', '81c2c92e47edaee6', '92722c851482353b',
'a2bfe8a14cf10364', 'a81a664bbc423001', 'c24b8b70d0f89791', 'c76c51a30654be30',
'd192e819d6ef5218', 'd69906245565a910', 'f40e35855771202a', '106aa07032bbd1b8',
'19a4c116b8d2d0c8', '1e376c085141ab53', '2748774cdf8eeb99', '34b0bcb5e19b48a8',
'391c0cb3c5c95a63', '4ed8aa4ae3418acb', '5b9cca4f7763e373', '682e6ff3d6b2b8a3',
'748f82ee5defb2fc', '78a5636f43172f60', '84c87814a1f0ab72', '8cc702081a6439ec',
'90befffa23631e28', 'a4506cebde82bde9', 'bef9a3f7b2c67915', 'c67178f2e372532b',
'ca273eceea26619c', 'd186b8c721c0c207', 'eada7dd6cde0eb1e', 'f57d4f7fee6ed178',
'06f067aa72176fba', '0a637dc5a2c898a6', '113f9804bef90dae', '1b710b35131c471b',
'28db77f523047d84', '32caab7b40c72493', '3c9ebe0a15c9bebc', '431d67c49c100d4c',
'4cc5d4becb3e42b6', '597f299cfc657e2a', '5fcb6fab3ad6faec', '6c44198c4a475817'
);
for ($i = 0; $i < 80; $i++) {
$k[$i] = new BigInteger($k[$i], 16);
}
}
// Pre-processing
$length = strlen($m);
// to round to nearest 112 mod 128, we'll add 128 - (length + (128 - 112)) % 128
$m.= str_repeat(chr(0), 128 - (($length + 16) & 0x7F));
$m[$length] = chr(0x80);
// we don't support hashing strings 512MB long
$m.= pack('N4', 0, 0, 0, $length << 3);
// Process the message in successive 1024-bit chunks
$chunks = str_split($m, 128);
foreach ($chunks as $chunk) {
$w = array();
for ($i = 0; $i < 16; $i++) {
$temp = new BigInteger(self::_string_shift($chunk, 8), 256);
$temp->setPrecision(64);
$w[] = $temp;
}
// Extend the sixteen 32-bit words into eighty 32-bit words
for ($i = 16; $i < 80; $i++) {
$temp = array(
$w[$i - 15]->bitwise_rightRotate(1),
$w[$i - 15]->bitwise_rightRotate(8),
$w[$i - 15]->bitwise_rightShift(7)
);
$s0 = $temp[0]->bitwise_xor($temp[1]);
$s0 = $s0->bitwise_xor($temp[2]);
$temp = array(
$w[$i - 2]->bitwise_rightRotate(19),
$w[$i - 2]->bitwise_rightRotate(61),
$w[$i - 2]->bitwise_rightShift(6)
);
$s1 = $temp[0]->bitwise_xor($temp[1]);
$s1 = $s1->bitwise_xor($temp[2]);
$w[$i] = clone $w[$i - 16];
$w[$i] = $w[$i]->add($s0);
$w[$i] = $w[$i]->add($w[$i - 7]);
$w[$i] = $w[$i]->add($s1);
}
// Initialize hash value for this chunk
$a = clone $hash[0];
$b = clone $hash[1];
$c = clone $hash[2];
$d = clone $hash[3];
$e = clone $hash[4];
$f = clone $hash[5];
$g = clone $hash[6];
$h = clone $hash[7];
// Main loop
for ($i = 0; $i < 80; $i++) {
$temp = array(
$a->bitwise_rightRotate(28),
$a->bitwise_rightRotate(34),
$a->bitwise_rightRotate(39)
);
$s0 = $temp[0]->bitwise_xor($temp[1]);
$s0 = $s0->bitwise_xor($temp[2]);
$temp = array(
$a->bitwise_and($b),
$a->bitwise_and($c),
$b->bitwise_and($c)
);
$maj = $temp[0]->bitwise_xor($temp[1]);
$maj = $maj->bitwise_xor($temp[2]);
$t2 = $s0->add($maj);
$temp = array(
$e->bitwise_rightRotate(14),
$e->bitwise_rightRotate(18),
$e->bitwise_rightRotate(41)
);
$s1 = $temp[0]->bitwise_xor($temp[1]);
$s1 = $s1->bitwise_xor($temp[2]);
$temp = array(
$e->bitwise_and($f),
$g->bitwise_and($e->bitwise_not())
);
$ch = $temp[0]->bitwise_xor($temp[1]);
$t1 = $h->add($s1);
$t1 = $t1->add($ch);
$t1 = $t1->add($k[$i]);
$t1 = $t1->add($w[$i]);
$h = clone $g;
$g = clone $f;
$f = clone $e;
$e = $d->add($t1);
$d = clone $c;
$c = clone $b;
$b = clone $a;
$a = $t1->add($t2);
}
// Add this chunk's hash to result so far
$hash = array(
$hash[0]->add($a),
$hash[1]->add($b),
$hash[2]->add($c),
$hash[3]->add($d),
$hash[4]->add($e),
$hash[5]->add($f),
$hash[6]->add($g),
$hash[7]->add($h)
);
}
// Produce the final hash value (big-endian)
// (\phpseclib\Crypt\Hash::hash() trims the output for hashes but not for HMACs. as such, we trim the output here)
$temp = $hash[0]->toBytes() . $hash[1]->toBytes() . $hash[2]->toBytes() . $hash[3]->toBytes() .
$hash[4]->toBytes() . $hash[5]->toBytes() . $hash[6]->toBytes() . $hash[7]->toBytes();
return $temp;
}
/**
* String Shift
*
* Inspired by array_shift
*
* @param string $string
* @param int $index
* @return string
* @access private
*/
static function _string_shift(&$string, $index = 1)
{
$substr = substr($string, 0, $index);
$string = substr($string, $index);
return $substr;
}
}