Mcrypt
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

Описание

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().

Список параметров

algorithm

The algorithm to be used.

algorithm_directory

The algorithm_directory parameter is used to locate the encryption module. When you supply a directory name, it is used. When you set it to an empty string (""), the value set by the mcrypt.algorithms_dir php.ini directive is used. When it is not set, the default directory that is used is the one that was compiled into libmcrypt (usually /usr/local/lib/libmcrypt).

mode

The mode to be used.

mode_directory

The mode_directory parameter is used to locate the encryption module. When you supply a directory name, it is used. When you set it to an empty string (""), the value set by the mcrypt.modes_dir php.ini directive is used. When it is not set, the default directory that is used is the one that was compiled-in into libmcrypt (usually /usr/local/lib/libmcrypt).

Возвращаемые значения

Normally it returns an encryption descriptor, or FALSE on error.

Примеры

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, 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";
?>

Смотрите также

Mcrypt
PHP Manual
Участник рейтинга Тэглайн 2010