mcrypt_create_iv
(PHP 4, PHP 5, PHP 7 < 7.2.0, PECL mcrypt >= 1.0.0)
mcrypt_create_iv — Creates an initialization vector (IV) from a random source
Diese Funktion wurde in PHP 7.1.0 als DEPRECATED (veraltet) markiert und in PHP 7.2.0 REMOVED (entfernt).
Alternativ können die folgenden Funktionen verwendet werden:
Beschreibung
$size, int $source = MCRYPT_DEV_URANDOM): stringCreates an initialization vector (IV) from a random source.
The IV is only meant to give an alternative seed to the encryption routines. This IV does not need to be secret at all, though it can be desirable. You even can send it along with your ciphertext without losing security.
Parameter-Liste
-
size -
The size of the IV.
-
source -
The source of the IV. The source can be
MCRYPT_RAND(system random number generator),MCRYPT_DEV_RANDOM(read data from /dev/random) andMCRYPT_DEV_URANDOM(read data from /dev/urandom). Prior to 5.3.0,MCRYPT_RANDwas the only one supported on Windows.Note that the default value of this parameter was
MCRYPT_DEV_RANDOMprior to PHP 5.6.0.Hinweis: Note that
MCRYPT_DEV_RANDOMmay block until more entropy is available.
Rückgabewerte
Returns the initialization vector, or false on error.
Beispiele
Beispiel #1 mcrypt_create_iv() Example
<?php
$size = mcrypt_get_iv_size(MCRYPT_CAST_256, MCRYPT_MODE_CFB);
$iv = mcrypt_create_iv($size, MCRYPT_DEV_RANDOM);
?>
Siehe auch
- » http://www.ciphersbyritter.com/GLOSSARY.HTM#IV
- » http://www.quadibloc.com/crypto/co0409.htm
- Chapter 9.3 of Applied Cryptography by Schneier (ISBN 0-471-11709-9)
- random_bytes() - Generates cryptographically secure pseudo-random bytes
