hash_hmac_file
hash_init
Hash Functions
PHP Manual

# hash_hmac

(PHP 5 >= 5.1.2, PECL hash >= 1.1)

hash_hmac — Generate a keyed hash value using the HMAC method

### Description

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

### Parameters

`algo`

  Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..) See hash_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.

`raw_output`

  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 `raw_output` is set to true in which case the raw binary representation of the message digest is returned. Returns `FALSE` when `algo` is unknown.

### Examples

Example #1 hash_hmac() example

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

The above example will output:

    b8e7ae12510bdfb1812e463a7f086122cf37e4f7

### See Also

- hash() - Generate a hash value (message digest)
- hash_algos() - Return a list of registered hashing algorithms
- hash_init() - Initialize an incremental hashing context
- hash_hmac_file() - Generate a keyed hash value using the HMAC method and the contents of a given file

hash_hmac_file
hash_init
Hash Functions
PHP Manual