| public static pbkdf2 ( string $password, string $salt, integer $iterationCount, integer $derivedKeyLength, string $algorithm = 'sha256' ) : string | ||
| $password | string | Input string / password |
| $salt | string | The salt |
| $iterationCount | integer | Hash iteration count |
| $derivedKeyLength | integer | Derived key length |
| $algorithm | string | Hash algorithm to use, see hash_algos(), defaults to sha256 |
| return | string | The computed derived key as raw binary data |
public static function pbkdf2($password, $salt, $iterationCount, $derivedKeyLength, $algorithm = 'sha256')
{
$hashLength = strlen(hash($algorithm, null, true));
$keyBlocksToCompute = ceil($derivedKeyLength / $hashLength);
$derivedKey = '';
for ($block = 1; $block <= $keyBlocksToCompute; $block++) {
$iteratedBlock = hash_hmac($algorithm, $salt . pack('N', $block), $password, true);
for ($iteration = 1, $iteratedHash = $iteratedBlock; $iteration < $iterationCount; $iteration++) {
$iteratedHash = hash_hmac($algorithm, $iteratedHash, $password, true);
$iteratedBlock ^= $iteratedHash;
}
$derivedKey .= $iteratedBlock;
}
return substr($derivedKey, 0, $derivedKeyLength);
} /**
* @test
* @dataProvider pbkdf2TestVectors
*/
public function pbkdf2TestVectorsAreCorrect($password, $salt, $iterationCount, $derivedKeyLength, $output)
{
$result = Algorithms::pbkdf2($password, $salt, $iterationCount, $derivedKeyLength, 'sha1');
$this->assertEquals(unpack('H*', pack('H*', $output)), unpack('H*', $result));
}
