hash_hmac

(PHP 5 >= 5.1.2, PECL hash:1.1-1.5)

hash_hmac — Generate a keyed hash value using the HMAC method

설명

string hash_hmac ( string $algo , string $data , string $key [, bool $raw_output ] )

매개변수

algo: Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..)
data: Message to be hashed.
key: Shared secret key used for generating the HMAC variant of the message digest.
raw_output: When set to TRUE, outputs raw binary data. Default value (FALSE) outputs lowercase hexits.

반환값

Returns a string containing the calculated message digest as lowercase hexits unless raw_output is set to true in which case the raw binary representation of the message digest is returned.

예제

Example#1 hash_hmac() example


<?php
echo hash_hmac('ripemd160', 'The quick brown fox jumped over the lazy dog.', 'secret');
?>

위 예제의 출력:

b8e7ae12510bdfb1812e463a7f086122cf37e4f7

참고

add a note User Contributed Notes
hash_hmac

Carlos Averett(caverett*@*corecodec,net)
03-Jul-2008 03:54


Generating OATH-compliant OTP (one time passwords) results in PHP:



<?php

$otp = oath_truncate (oath_hotp ($key, $counter), $length);

function oath_hotp ($key, $counter) {

        // Counter

        $bin_counter = pack ('C*', $counter);



        // Pad to 8 chars

        if (strlen ($bin_counter) < 8) {

                $bin_counter = str_repeat (chr(0), 8 - strlen ($bin_counter)) . $bin_counter;

        }



        // HMAC

        $hash = hash_hmac ('sha1', $bin_counter, $key);

        return $hash;

}



function oath_truncate ($hash, $length = 6) {

        // The last byte is used as an offset

        $offset = hexdec (substr ($hash, 38)) & 0xf;



        // Extract the relevant part, and clear the first bit

        $hex_truncated = substr ($hash, $offset * 2, 8);

        $bin_truncated = decbin (hexdec ($hex_truncated));

        $bin_truncated[0] = '0';

        $dec_truncated = bindec ($bin_truncated);



        return substr ($dec_truncated, 0 - $length);

}

?>

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hash_init

hash_hmac_file

Last updated: Sun, 25 Nov 2007