note 109158 added to function.hash-hmac
| From: | kolonistatxinitdotru | Date: | Sun, 24 Jun 2012 20:15:02 +0000 |
| Subject: | note 109158 added to function.hash-hmac | ||
| Groups: | php.notes | ||
| Request: | Send a blank email to php-notes+get-188778@lists.php.net to get a copy of this message | ||
Edward, try this implementation, which I fixed after letter from one user:
<?php
/**
* Implementation of the PBKDF2 key derivation function as described in
* RFC 2898.
*
* @param string $PRF Hash algorithm.
* @param string $P Password.
* @param string $S Salt.
* @param int $c Iteration count.
* @param mixed $dkLen Derived key length (in octets). If $dkLen is FALSE
* then length will be set to $PRF output length (in
* octets).
* @param bool $raw_output When set to TRUE, outputs raw binary data. FALSE
* outputs lowercase hexits.
* @return mixed Derived key or FALSE if $dkLen > (2^32 - 1) * hLen (hLen
* denotes the length in octets of $PRF output).
*/
function pbkdf2($PRF, $P, $S, $c, $dkLen = false, $raw_output = false) {
//default $hLen is $PRF output length
$hLen = strlen(hash($PRF, '', true));
if ($dkLen === false) $dkLen = $hLen;
//4294967295 == pow(2, 32) - 1
if ($dkLen <= $hLen * 4294967295) {
$DK = '';
//create key
$blocks_count = ceil($dkLen / $hLen);
for ($block = 1; $block <= $blocks_count; $block++) {
//initial hash for this block
$ib = $h = hash_hmac($PRF, $S.pack('N', $block), $P, true);
//perform block iterations
for ($i = 1; $i < $c; $i++) {
$ib ^= ($h = hash_hmac($PRF, $h, $P, true));
}
//append iterated block
$DK .= $ib;
}
$DK = substr($DK, 0, $dkLen);
if (!$raw_output) $DK = bin2hex($DK);
return $DK;
//derived key too long
} else {
return false;
}
}
?>
It seems to be a lot faster compared to the implementation you mentioned below.
I use this file to test PBKDF2 with PKCS #5 PBKDF2 Test Vectors:
#!/usr/bin/php
<?php
require_once 'pbkdf2.inc.php';
//require_once 'pbkdf2_v1.inc.php';
//from http://tools.ietf.org/html/draft-josefsson-pbkdf2-test-vectors-06
$test_vectors = [
[
'P' => "password",
'S' => "salt",
'c' => 1,
'dkLen' => 20,
'DK' => '0c60c80f961f0e71f3a9b524af6012062fe037a6'
],
[
'P' => "password",
'S' => "salt",
'c' => 2,
'dkLen' => 20,
'DK' => 'ea6c014dc72d6f8ccd1ed92ace1d41f0d8de8957'
],
[
'P' => "password",
'S' => "salt",
'c' => 4096,
'dkLen' => 20,
'DK' => '4b007901b765489abead49d926f721d065a429c1'
],
[
'P' => "password",
'S' => "salt",
'c' => 16777216,
'dkLen' => 20,
'DK' => 'eefe3d61cd4da4e4e9945b3d6ba2158c2634e984'
],
[
'P' => "passwordPASSWORDpassword",
'S' => "saltSALTsaltSALTsaltSALTsaltSALTsalt",
'c' => 4096,
'dkLen' => 25,
'DK' => '3d2eec4fe41c849b80c8d83662c0e44a8b291a964cf2f07038'
],
[
'P' => "pass\0word",
'S' => "sa\0lt",
'c' => 4096,
'dkLen' => 16,
'DK' => '56fa6aa75548099dcc37d7f03425e0c3'
]
];
$time = microtime(true);
foreach ($test_vectors as $vector) {
$pbkdf2 = pbkdf2('sha1', $vector['P'], $vector['S'],
$vector['c'], $vector['dkLen']);
//$pbkdf2 = bin2hex($pbkdf2);
echo
"pbkdf2(sha1, {$vector['P']}, {$vector['S']},
{$vector['c']}, {$vector['dkLen']}): $pbkdf2 - ",
($pbkdf2 === $vector['DK']) ? 'PASS' : 'WRONG',
"\n";
}
$time = microtime(true) - $time;
echo "Time: $time s\n";
?>
----
Server IP: 195.54.192.44
Probable Submitter: 178.210.22.117
----
Manual Page -- http://www.php.net/manual/en/function.hash-hmac.php
Edit -- https://master.php.net/note/edit/109158
Del: integrated -- https://master.php.net/note/delete/109158/integrated
Del: useless -- https://master.php.net/note/delete/109158/useless
Del: bad code -- https://master.php.net/note/delete/109158/bad+code
Del: spam -- https://master.php.net/note/delete/109158/spam
Del: non-english -- https://master.php.net/note/delete/109158/non-english
Del: in docs -- https://master.php.net/note/delete/109158/in+docs
Del: other reasons-- https://master.php.net/note/delete/109158
Reject -- https://master.php.net/note/reject/109158
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