TYPO3 Core

- hash

* Returns a proper HMAC on a given input string and secret TYPO3 encryption key.

*

* @param string Input string to create HMAC from

* @return string resulting (hexadecimal) HMAC currently with a length of 40 (HMAC-SHA-1)

*/

public static function hmac($input) {

$hashAlgorithm = 'sha1';

$hashBlocksize = 64;

$hmac = '';

if (extension_loaded('hash') && function_exists('hash_hmac') && function_exists('hash_algos') && in_array($hashAlgorithm, hash_algos())) {

$hmac = hash_hmac($hashAlgorithm, $input, $GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey']);

} else {

// outer padding

$opad = str_repeat(chr(0x5C), $hashBlocksize);

// innner padding

$ipad = str_repeat(chr(0x36), $hashBlocksize);

if (strlen($GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey']) > $hashBlocksize) {

// keys longer than blocksize are shorten

$key = str_pad(pack('H*', call_user_func($hashAlgorithm, $GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'])), $hashBlocksize, chr(0x00));

} else {

// keys shorter than blocksize are zero-padded

$key = str_pad($GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'], $hashBlocksize, chr(0x00));

}

$hmac = call_user_func($hashAlgorithm, ($key^$opad) . pack('H*', call_user_func($hashAlgorithm, ($key^$ipad) . $input)));

}

return $hmac;

}

/**

// Tests concerning hmac

//////////////////////////////////

/**

* @test

*/

public function hmacReturnsHashOfProperLength() {

$hmac = t3lib_div::hmac('message');

$this->assertTrue(!empty($hmac) && is_string($hmac));

$this->assertTrue(strlen($hmac) == 40);

}

/**

* @test

*/

public function hmacReturnsEqualHashesForEqualInput() {

$msg0 = 'message';

$msg1 = 'message';

$this->assertEquals(t3lib_div::hmac($msg0), t3lib_div::hmac($msg1));

}

/**

* @test

*/

public function hmacReturnsNotEqualHashesForNotEqualInput() {

$msg0 = 'message0';

$msg1 = 'message1';

$this->assertNotEquals(t3lib_div::hmac($msg0), t3lib_div::hmac($msg1));

}

//////////////////////////////////