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<mcrypt_enc_get_modes_namemcrypt_enc_is_block_algorithm>
^Mcrypt FunctionsLast updated: Mon, 26 Oct 2026

mcrypt_enc_get_supported_key_sizes

(PHP 4 >= 4.0.2, PHP 5, PHP 7 < 7.2.0, PECL mcrypt >= 1.0.0)

mcrypt_enc_get_supported_key_sizes — Returns an array with the supported keysizes of the opened algorithm

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.

Description

function mcrypt_enc_get_supported_key_sizes(resource $td): array

Gets the supported key sizes of the opened algorithm.

Parameters

td

The encryption descriptor.

Return Values

Returns an array with the key sizes supported by the algorithm specified by the encryption descriptor. If it returns an empty array then all key sizes between 1 and mcrypt_enc_get_key_size() are supported by the algorithm.

Examples

Example #1 mcrypt_enc_get_supported_key_sizes() example

<?php
    $td = mcrypt_module_open('rijndael-256', '', 'ecb', '');
    var_dump(mcrypt_enc_get_supported_key_sizes($td));
?>

The above example will output:

array(3) {
  [0]=>
  int(16)
  [1]=>
  int(24)
  [2]=>
  int(32)
}

<mcrypt_enc_get_modes_namemcrypt_enc_is_block_algorithm>
^Mcrypt FunctionsLast updated: Mon, 26 Oct 2026