mcrypt_module_is_block_mode
mcrypt_module_self_test
Mcrypt Functions
PHP Manual

# mcrypt_module_open

(PHP 4 >= 4.0.2, PHP 5)

mcrypt_module_open — Opens the module of the algorithm and the mode to be used

### Descripción

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).

### Ejemplos

Example #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.

### Ejemplos

Example #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, use 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";
?>`

See also mcrypt_module_close(), mcrypt_generic(), mdecrypt_generic(), mcrypt_generic_init(), and mcrypt_generic_deinit().

mcrypt_module_is_block_mode
mcrypt_module_self_test
Mcrypt Functions
PHP Manual