mcrypt_get_iv_size - Returns the size of the IV belonging to a specific cipher/mode combination
Вернуться к: Mcrypt
mcrypt_get_iv_size
(PHP 4 >= 4.0.2, PHP 5, PHP 7)
mcrypt_get_iv_size — Returns the size of the IV belonging to a specific cipher/mode combination
Описание
$cipher
, string $mode
)
Gets the size of the IV belonging to a specific
cipher
/mode
combination.
It is more useful to use the mcrypt_enc_get_iv_size() function as this uses the resource returned by mcrypt_module_open().
Список параметров
-
cipher
-
Одна из констант
MCRYPT_ciphername
или название алгоритма в виде строки. -
mode
-
Одна из констант
MCRYPT_MODE_modename
, либо одна из следующих строк: "ecb", "cbc", "cfb", "ofb", "nofb" и "stream".The IV is ignored in ECB mode as this mode does not require it. You will need to have the same IV (think: starting point) both at encryption and decryption stages, otherwise your encryption will fail.
Возвращаемые значения
Returns the size of the Initialization Vector (IV) in bytes. On error the
function returns FALSE
. If the IV is ignored in the specified cipher/mode
combination zero is returned.
Примеры
Пример #1 mcrypt_get_iv_size() Example
<?php
echo mcrypt_get_iv_size(MCRYPT_CAST_256, MCRYPT_MODE_CFB) . "\n";
echo mcrypt_get_iv_size('des', 'ecb') . "\n";
?>
Смотрите также
- mcrypt_get_block_size() - Gets the block size of the specified cipher
- mcrypt_enc_get_iv_size() - Returns the size of the IV of the opened algorithm
- mcrypt_create_iv() - Creates an initialization vector (IV) from a random source
Вернуться к: Mcrypt