mdecrypt_generic

    (PHP 4 >= 4.0.2, PHP 5, PHP 7 < 7.2.0, PECL mcrypt >= 1.0.0)

    mdecrypt_generic — Decrypts data

    Advertencia

    Esta función ha sido declarada OBSOLETA a partir de PHP 7.1.0 y será ELIMINADA a partir de PHP 7.2.0. Su uso está totalmente desaconsejado.

    Descripción

    mdecrypt_generic(resource$td, string$data): string

    This function decrypts data. Note that the length of the returned string can in fact be longer than the unencrypted string, due to the padding of the data.

    Parámetros

    td

    An encryption descriptor returned by mcrypt_module_open()

    data

    Encrypted data.

    Valores devueltos

    Returns decrypted string.

    Ejemplos

    Ejemplo #1 mdecrypt_generic() Example

    <?php

    $key = 'this is a very long key, even too long for the cipher';
    $plain_text = 'very important data';


    $td = mcrypt_module_open('des', '', 'ecb', '');
    $key = substr($key, 0, mcrypt_enc_get_key_size($td));
    $iv_size = mcrypt_enc_get_iv_size($td);
    $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);


    if (mcrypt_generic_init($td, $key, $iv) != -1) {


    $c_t = mcrypt_generic($td, $plain_text);
    mcrypt_generic_deinit($td);


    mcrypt_generic_init($td, $key, $iv);
    $p_t = mdecrypt_generic($td, $c_t);


    mcrypt_generic_deinit($td);
    mcrypt_module_close($td);
    }

    if (    strncmp($p_t, $plain_text, strlen($plain_text)) == 0) {
    echo     "ok\n";
    } else {
    echo     "error\n";
    }
    ?>

    The example above shows how to check if the data before the encryption is the same as the data after the decryption. It is very important to reinitialize the encryption buffer with mcrypt_generic_init() before you try to decrypt the data.

    The decryption handle should always be initialized with mcrypt_generic_init() with a key and an IV before calling this function. Where the encryption is done, you should free the encryption buffers by calling mcrypt_generic_deinit(). See mcrypt_module_open() for an example.

    Ver también

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