mcrypt_cbc
(PHP 4, PHP 5)
mcrypt_cbc — Шифрует/дешифрует данные в режиме CBC
Описание
string mcrypt_cbc
( int
$cipher
, string $key
, string $data
, int $mode
[, string $iv
] )
string mcrypt_cbc
( string
$cipher
, string $key
, string $data
, int $mode
[, string $iv
] )
Первый прототип работает при связке с libmcrypt 2.2.x, второй - при связке с libmcrypt 2.4.x или выше.
Параметр mode
должен быть либо
MCRYPT_ENCRYPT
, либо
MCRYPT_DECRYPT
.
Эта функция больше не используется. Смотрите mcrypt_generic() и mdecrypt_generic() для замены.
Внимание
Эта функция была помечена УСТАРЕВШЕЙ начиная с версии PHP 5.5.0. Крайне не рекомендуется полагаться на эту функцию.
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Криптографические расширения
- Mcrypt
- mcrypt_cbc
- mcrypt_cfb
- mcrypt_create_iv
- mcrypt_decrypt
- mcrypt_ecb
- mcrypt_enc_get_algorithms_name
- mcrypt_enc_get_block_size
- mcrypt_enc_get_iv_size
- mcrypt_enc_get_key_size
- mcrypt_enc_get_modes_name
- mcrypt_enc_get_supported_key_sizes
- mcrypt_enc_is_block_algorithm_mode
- mcrypt_enc_is_block_algorithm
- mcrypt_enc_is_block_mode
- mcrypt_enc_self_test
- mcrypt_encrypt
- mcrypt_generic_deinit
- mcrypt_generic_end
- mcrypt_generic_init
- mcrypt_generic
- mcrypt_get_block_size
- mcrypt_get_cipher_name
- mcrypt_get_iv_size
- mcrypt_get_key_size
- mcrypt_list_algorithms
- mcrypt_list_modes
- mcrypt_module_close
- mcrypt_module_get_algo_block_size
- mcrypt_module_get_algo_key_size
- mcrypt_module_get_supported_key_sizes
- mcrypt_module_is_block_algorithm_mode
- mcrypt_module_is_block_algorithm
- mcrypt_module_is_block_mode
- mcrypt_module_open
- mcrypt_module_self_test
- mcrypt_ofb
- mdecrypt_generic
Коментарии
The following code is to
encrypt-->encode
decode-->decrypt
<?php
$stuff="String to enc/enc/dec/dec =,=,";
$key="XiTo74dOO09N48YeUmuvbL0E";
function nl() {
echo "<br/> \n";
}
$iv = mcrypt_create_iv (mcrypt_get_block_size (MCRYPT_TripleDES, MCRYPT_MODE_CBC), MCRYPT_DEV_RANDOM);
// Encrypting
function encrypt($string, $key) {
$enc = "";
global $iv;
$enc=mcrypt_cbc (MCRYPT_TripleDES, $key, $string, MCRYPT_ENCRYPT, $iv);
return base64_encode($enc);
}
// Decrypting
function decrypt($string, $key) {
$dec = "";
$string = trim(base64_decode($string));
global $iv;
$dec = mcrypt_cbc (MCRYPT_TripleDES, $key, $string, MCRYPT_DECRYPT, $iv);
return $dec;
}
$encrypted = encrypt($stuff, $key);
$decrypted = decrypt($encrypted, $key);
echo "Encrypted is ".$encrypted . nl();
echo "Decrypted is ".$decrypted . nl();
?>
Notes on the result
-o running the script from the command line 1 time
php script.php works correct
-o if i ran the script in a loop i.e.
#!/bin/bash
for x in `seq 100`
do
echo $x
php script.php >> LOG.text
sleep 1
done
it gets slower after the 10th time
+ inconsistent output
sometimes correct some with encrypted characters at the end of the decrypted string
-o Firefox on Linux it decrypts to the original string but appends
some encryption at the end of the decrypted sting
-o running the script on the browser from windows on Firefox,
Google Chrome, IE7 works fine for just few times
"refresh every few seconds"
if refresh fast it doesn't work correctly,
some times returns the decrypted as encrypted!
some times returns mix of encrypted & decrypted
I thought if sharing that test for those functions might be
useful for some body
if you use blowfish and somehow when you compare strings before and after it was (usually when it's shorter than 8 or 16 bytes) you might notice the difference, it comes out that this function does not remove padding, as a result you get a bunch of nulls at the end.
use
$decrypted = rtrim($decrypted,"\0");
to fix it
The PERL libraries have changed a little bit and getting PHP and PERL to mcrypt together can be confusing, so here is a current example;
PHP
===
<?php
$string = 'Some Secret thing I want to encrypt';
$iv = '12345678';
$passphrase = '8chrsLng';
$encryptedString = encryptString($string, $passphrase, $iv);
// Expect: 7DjnpOXG+FrUaOuc8x6vyrkk3atSiAf425ly5KpG7lOYgwouw2UATw==
function encryptString($unencryptedText, $passphrase, $iv) {
$enc = mcrypt_encrypt(MCRYPT_BLOWFISH, $passphrase, $unencryptedText, MCRYPT_MODE_CBC, $iv);
return base64_encode($enc);
}
?>
PERL
====
$encryptedString = '7DjnpOXG+FrUaOuc8x6vyrkk3atSiAf425ly5KpG7lOYgwouw2UATw==';
$iv = '12345678';
$passphrase = '8chrsLng';
$string = &decryptPhpEncrypted $encryptedString, $passphrase, $iv;
# Expect: Some Secret thing I want to encrypt
sub decryptPhpEncrypted() {
my ($encryptedString, $passphrase, $iv) = @_;
my $keysize = length($passphrase);
use Crypt::CBC;
$cipher = Crypt::CBC->new( {'key' => $encryptedString,
'cipher'=> 'Blowfish',
'iv' => $iv,
'keysize' => $keysize,
'regenerate_key' => 0,
'padding' => 'null',
'prepend_iv' => 0});
return $cipher->decrypt($encryptedString);
}