While not specified in the description, this function, just like mcrypt_enc_get_key_size(), returns the cipher's largest key size in BYTES.
(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().
cipherUna tra le costanti MCRYPT_ciphername, oppure il nome dell'algoritmo sotto forma di stringa.
modeUna tra le costanti MCRYPT_MODE_modename, oppure una tra le seguenti stringhe: "ecb", "cbc", "cfb", "ofb", "nofb" o "stream".
Returns the maximum supported key size of the algorithm in bytes
o false in caso di fallimento.
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.
Il precedente esempio visualizzerà:
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