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mcrypt_get_key_size

PHP function Edit on GitHub ✎

(PHP 4, PHP 5, PHP 7 < 7.2.0, PECL mcrypt >= 1.0.0)

Gets the key size of the specified cipher

Removed-7-2-0

Description

mcrypt_get_key_size(int $cipher): int|false

mcrypt_get_key_size(string $cipher, string $mode): int|false

The first prototype is when linked against libmcrypt 2.2.x, the second when linked against libmcrypt 2.4.x or 2.5.x.

mcrypt_get_key_size() is used to get the size of a key of the specified cipher (in combination with an encryption mode).

It is more useful to use the mcrypt_enc_get_key_size() function as this uses the resource returned by mcrypt_module_open().

Returns the maximum supported key size of the algorithm in bytes Falseforfailure.

php

<?php
    echo mcrypt_get_key_size('tripledes', 'ecb');
?>

The example above shows how to use this function when linked against libmcrypt 2.4.x or 2.5.x.

The above example will output:

output