PHP 7.2.0 Beta 3 Released


(PHP 4, PHP 5)

mcrypt_get_key_sizeGets the key size of the specified cipher


int mcrypt_get_key_size ( int $cipher )
int mcrypt_get_key_size ( string $cipher , string $mode )

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().

Elenco dei parametri


Una tra le costanti MCRYPT_ciphername, oppure il nome dell'algoritmo sotto forma di stringa.


Una tra le costanti MCRYPT_MODE_modename, oppure una tra le seguenti stringhe: "ecb", "cbc", "cfb", "ofb", "nofb" o "stream".

Valori restituiti

Returns the maximum supported key size of the algorithm in bytes o FALSE in caso di fallimento.


Example #1 mcrypt_get_key_size() Example

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 visualizzerĂ :


Vedere anche:

add a note add a note

User Contributed Notes 1 note

7 years ago
While not specified in the description, this function, just like mcrypt_enc_get_key_size(), returns the cipher's largest key size in BYTES.
To Top