Generate a keyed hash value using the HMAC method

Description

hash_hmac(
    string $algo,
    string $data,
    string $key,
    bool $binary = false
): string

Parameters

algo: Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..) See hash_hmac_algos() for a list of supported algorithms.
data: Message to be hashed.
key: Shared secret key used for generating the HMAC variant of the message digest.
binary: When set to true, outputs raw binary data. false outputs lowercase hexits.

Return Values

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

Errors/Exceptions

Throws a ValueError exception if algo is unknown or is a non-cryptographic hash function.

Changelog

Version	Description
8.0.0	Now throws a ValueError exception if `algo` is unknown or is a non-cryptographic hash function; previously, `false` was returned instead.
7.2.0	Usage of non-cryptographic hash functions (adler32, crc32, crc32b, fnv132, fnv1a32, fnv164, fnv1a64, joaat) was disabled.

Examples

Example #1 hash_hmac() example

<?php
echo hash_hmac('sha256', 'The quick brown fox jumped over the lazy dog.', 'secret');
?>

The above example will output:

9c5c42422b03f0ee32949920649445e417b2c634050833c5165704b825c2a53b

hash_hmac