mcrypt_get_block_size

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

mcrypt_get_block_size — Gets the block size of the specified cipher

Warning

This function has been DEPRECATED as of PHP 7.1.0 and REMOVED as of PHP 7.2.0. Relying on this function is highly discouraged.

function mcrypt_get_block_size(int $cipher): int|false

function mcrypt_get_block_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_block_size() is used to get the size of a block of the specified cipher (in combination with an encryption mode).

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

cipher: One of the MCRYPT_ciphername constants, or the name of the algorithm as string.
mode: One of the MCRYPT_MODE_modename constants, or one of the following strings: "ecb", "cbc", "cfb", "ofb", "nofb" or "stream".

Returns the algorithm block size in bytes or false on failure.

Example #1 mcrypt_get_block_size() example

This example shows how to use this function when linked against libmcrypt 2.4.x and 2.5.x.

<?php

echo mcrypt_get_block_size('tripledes', 'ecb'); // 8

?>