(PHP 4, PHP 5, PHP 7 < 7.2.0, PECL mcrypt >= 1.0.0)
mcrypt_get_key_size — Gets the key size of the specified cipher
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.
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().
cipherOne of the MCRYPT_ciphername constants, or the name of the algorithm as string.
modeOne of the MCRYPT_MODE_modename constants, or one of the following strings: "ecb", "cbc", "cfb", "ofb", "nofb" or "stream".
Returns the maximum supported key size of the algorithm in bytes
or false on failure.
Example #1 mcrypt_get_key_size() Example
<?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:
24