(PHP 4 >= 4.0.2, PHP 5)mcrypt_module_open -- Opens the module of the algorithm and the mode to be used

Description

resource mcrypt_module_open (string algorithm, string algorithm_directory, string mode, string mode_directory)

This function opens the module of the algorithm and the mode to be used.

The name of the algorithm is specified in algorithm, e.g. "twofish" or is

one of the MCRYPT_ciphername constants. The module is closed by calling

mcrypt_module_close(). Normally it returns an

encryption descriptor, or FALSE on error.

The algorithm_directory and

mode_directory are used to locate the encryption

modules. When you supply a directory name, it is used. When you set one

of these to the empty string (""), the value set by the

mcrypt.algorithms_dir or

mcrypt.modes_dir ini-directive is used. When

these are not set, the default directories that are used are the ones

that were compiled in into libmcrypt (usually /usr/local/lib/libmcrypt).

Пример 1. mcrypt_module_open() examples <?php $td = mcrypt_module_open(MCRYPT_DES, '', MCRYPT_MODE_ECB, '/usr/lib/mcrypt-modes'); $td = mcrypt_module_open('rijndael-256', '', 'ofb', ''); ?>

The first line in the example above will try to open the DES cipher from

the default directory and the EBC mode from the directory

/usr/lib/mcrypt-modes. The second example uses

strings as name for the cipher and mode, this only works when the

extension is linked against libmcrypt 2.4.x or 2.5.x.

Пример 2. Using mcrypt_module_open() in encryption <?php /* Open the cipher */ $td = mcrypt_module_open('rijndael-256', '', 'ofb', ''); /* Create the IV and determine the keysize length, used MCRYPT_RAND * on Windows instead */ $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_DEV_RANDOM); $ks = mcrypt_enc_get_key_size($td); /* Create key */ $key = substr(md5('very secret key'), 0, $ks); /* Intialize encryption */ mcrypt_generic_init($td, $key, $iv); /* Encrypt data */ $encrypted = mcrypt_generic($td, 'This is very important data'); /* Terminate encryption handler */ mcrypt_generic_deinit($td); /* Initialize encryption module for decryption */ mcrypt_generic_init($td, $key, $iv); /* Decrypt encrypted string */ $decrypted = mdecrypt_generic($td, $encrypted); /* Terminate decryption handle and close module */ mcrypt_generic_deinit($td); mcrypt_module_close($td); /* Show string */ echo trim($decrypted). "\n"; ?>

The first line in the example above will try to open the DES cipher from

the default directory and the EBC mode from the directory

/usr/lib/mcrypt-modes. The second example uses

strings as name for the cipher and mode, this only works when the

extension is linked against libmcrypt 2.4.x or 2.5.x.

See also

mcrypt_module_close(),

mcrypt_generic(),

mdecrypt_generic(),

mcrypt_generic_init(), and

mcrypt_generic_deinit().

Пред.

Начало

След.

mcrypt_module_is_block_mode

Уровень выше

mcrypt_module_self_test