范例

Mcrypt can be used to encrypt and decrypt using the above mentioned ciphers. If you linked against libmcrypt-2.2.x, the four important mcrypt commands (mcrypt_cfb(), mcrypt_cbc(), mcrypt_ecb(), and mcrypt_ofb()) can operate in both modes which are named MCRYPT_ENCRYPT and MCRYPT_DECRYPT, respectively.

Example #1 Encrypt an input value with TripleDES under 2.2.x in ECB mode


<?php
$key = "this is a secret key";
$input = "Let us meet at 9 o'clock at the secret place.";

$encrypted_data = mcrypt_ecb (MCRYPT_3DES, $key, $input, MCRYPT_ENCRYPT);
?>

This example will give you the encrypted data as a string in $encrypted_data.

If you linked against libmcrypt 2.4.x or 2.5.x, these functions are still available, but it is recommended that you use the advanced functions.

Example #2 Encrypt an input value with TripleDES under 2.4.x and higher in ECB mode


<?php
    $key = "this is a secret key";
    $input = "Let us meet at 9 o'clock at the secret place.";

    $td = mcrypt_module_open('tripledes', '', 'ecb', '');
    $iv = mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
    mcrypt_generic_init($td, $key, $iv);
    $encrypted_data = mcrypt_generic($td, $input);
    mcrypt_generic_deinit($td);
    mcrypt_module_close($td);
?>

This example will give you the encrypted data as a string in $encrypted_data. For a full example see mcrypt_module_open().

PHP手册 - N: 范例

用户评论:

ivoras at gmail dot com (30-Aug-2010 02:36)

Note that there can be standard padding in block modes: http://www.di-mgt.com.au/cryptopad.html

jizz @ Nowhere (01-Jul-2008 08:36)

Ok after having a problem using triple des with .net/visual basic with php I think this could help someone: Visual Basic 9 with .net 2.0 Encrypting as a stream into the IO/Memory as bytes Then they get converted back after encryption I wanted to use base64 encoding to store the VB encryption The problem I found was ... I could En/Decrypt within VB and PHP just fine But when I tried to encrypt one in VB and decrypt in PHP I got the wrong values with the mcrypt function alone I found that at least with VB9 that the stream encryption uses a UTF char that is the value for how many missing bytes left in the 8 bit stream. So if you encrypt 1234 it will add chr(4) four times (the amount of missing bytes) In php use chr otherwise most browsers/client cant read it. Im not good at explaining things but the php code I figured out is below. It will find the missing bytes on input as visual basic does and replace as needed. For both encryption and decryption. Example is triple_des and cbc with self key and iv for storing in base64 $key = "E4HD9h4DhS23DYfhHemkS3Nf";// 24 bit Key $iv = "fYfhHeDm";// 8 bit IV $input = "Text to encrypt";// text to encrypt $bit_check=8;// bit amount for diff algor. $str= encrypt($input,$key,$iv,$bit_check); echo "Start: $input - Excrypted: $str - Decrypted: ".decrypt($str,$key,$iv,$bit_check); function encrypt($text,$key,$iv,$bit_check) { $text_num =str_split($text,$bit_check); $text_num = $bit_check-strlen($text_num[count($text_num)-1]); for ($i=0;$i<$text_num; $i++) {$text = $text . chr($text_num);} $cipher = mcrypt_module_open(MCRYPT_TRIPLEDES,'','cbc',''); mcrypt_generic_init($cipher, $key, $iv); $decrypted = mcrypt_generic($cipher,$text); mcrypt_generic_deinit($cipher); return base64_encode($decrypted); } function decrypt($encrypted_text,$key,$iv,$bit_check){ $cipher = mcrypt_module_open(MCRYPT_TRIPLEDES,'','cbc',''); mcrypt_generic_init($cipher, $key, $iv); $decrypted = mdecrypt_generic($cipher,base64_decode($encrypted_text)); mcrypt_generic_deinit($cipher); $last_char=substr($decrypted,-1); for($i=0;$i<$bit_check-1; $i++){ if(chr($i)==$last_char){ $decrypted=substr($decrypted,0,strlen($decrypted)-$i); break; } } return $decrypted; }