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Mcrypt Funktionen

<<Mcrypt Funktionen



(PHP 4, PHP 5)

mcrypt_cbcEncrypts/decrypts data in CBC mode


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 ] )

The first prototype is when linked against libmcrypt 2.2.x, the second when linked against libmcrypt 2.4.x or higher. The mode should be either MCRYPT_ENCRYPT or MCRYPT_DECRYPT.

This function should not be used anymore, see mcrypt_generic() and mdecrypt_generic() for replacements.

3 BenutzerBeiträge:
- Beiträge aktualisieren...
17.05.2009 6:56
The following code is to

="String to enc/enc/dec/dec =,=,";

nl() {
"<br/> \n";
$iv = mcrypt_create_iv (mcrypt_get_block_size (MCRYPT_TripleDES, MCRYPT_MODE_CBC), MCRYPT_DEV_RANDOM);

// Encrypting
function encrypt($string, $key) {
$enc = "";
$enc=mcrypt_cbc (MCRYPT_TripleDES, $key, $string, MCRYPT_ENCRYPT, $iv);


// Decrypting
function decrypt($string, $key) {
$dec = "";
$string = trim(base64_decode($string));
$dec = mcrypt_cbc (MCRYPT_TripleDES, $key, $string, MCRYPT_DECRYPT, $iv);

$encrypted = encrypt($stuff, $key);
$decrypted = decrypt($encrypted, $key);

"Encrypted is ".$encrypted . nl();
"Decrypted is ".$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.

for x in `seq 100`
        echo $x
        php script.php >> LOG.text
        sleep 1

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

28.04.2006 17:44
Here is a post similar to the one above, except this works for AES256
256 bit key and 128 bit block size... just make sure the $key variable is at least 48 characters long

---- PERL ---

my $key = '12345678901234567890123456789012345678901234567890';
my $CC = '4007000000027';

# You need Crypt::Rijndael installed for this to work
use Crypt::CBC;
my $cipher = Crypt::CBC->new( {'key' => substr($key,0,32),
                                'cipher'=> 'Rijndael',
                                'iv' => substr($key,32,16),
                                'regenerate_key' => 0,
                                'padding' => 'null',
                                'prepend_iv' => 0
my $encrypted = $cipher->encrypt($CC);

print "encrypted : ".$encrypted."\n";
print "decrypted : ".$cipher->decrypt($encrypted)."\n";

--- PHP ---

$key = '123456789012345678901234567890123456789012345678901234567890';
$CC = '4007000000027';

$encrypted = mcrypt_cbc(MCRYPT_RIJNDAEL_128,substr($key,0,32) ,$CC,MCRYPT_ENCRYPT,substr($key,32,16));
$decrypted = mcrypt_cbc(MCRYPT_RIJNDAEL_128,substr($key,0,32) ,$encrypted,MCRYPT_DECRYPT,substr($key,32,16));

echo "encrypted : ".bin2hex($encrypted);
eric at ez-llc dot com
11.03.2006 18:38
I was able get php and perl to play together with blowfish using cipher block chaining.  The blowfish key needs to be atleast 8 chars (even though blowfish min is 8 bits, perl didn't like keys smaller than 8 chars) and max 56.  The iv must be exactly 8 chars and padding needs to be null because php pads with nulls.  Also, php needs libmcrypt >= 2.4.9 to be compatible with perl.


use Crypt::CBC;
$cipher = Crypt::CBC->new( {'key' => 'my secret key',
                                    'cipher'=> 'Blowfish',
                                    'iv' => '12345678',
                                    'regenerate_key' => 0,
                                    'padding' => 'null',
                                    'prepend_iv' => 0
$cc = 'my secret text';
$encrypted = $cipher->encrypt($cc);
$decrypted = $cipher->decrypt($encrypted);

print "encrypted : ".$encrypted;
print "<br>";
print "decrypted : ".$decrypted;


$cc = 'my secret text';
$encrypted = mcrypt_cbc(MCRYPT_BLOWFISH,'my secret key',$cc,MCRYPT_ENCRYPT,'12345678');
$decrypted = mcrypt_cbc(MCRYPT_BLOWFISH, 'my secret key', $encrypted, MCRYPT_DECRYPT,'12345678');
echo "encrypted : ".$encrypted;
echo "<br>";
echo "decrypted : ".$decrypted;

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