problem with encryption query string

[xeonyk]

i have this code :

 

$security_keyword = md5("testing");

 

and i have this 2 function in function.php:

 

            function encrypt($data_input)
            {      
   		global $security_keyword;

	$key = $security_keyword;
	$td = mcrypt_module_open('cast-256', '', 'ecb', ''); 
	$iv = mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND); 
	mcrypt_generic_init($td, $key, $iv); 
	$encrypted_data = mcrypt_generic($td, $data_input); 
	mcrypt_generic_deinit($td); 
	mcrypt_module_close($td); 
	$encoded_64=base64_encode($encrypted_data); 
	return $encoded_64; 
}    


function decrypt($encoded_64)
{ 
	global $security_keyword;

	$decoded_64=base64_decode($encoded_64); 
	$key = $security_keyword;// same as you used to encrypt 
	$td = mcrypt_module_open('cast-256', '', 'ecb', ''); 
	$iv = mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND); 
	mcrypt_generic_init($td, $key, $iv); 
	$decrypted_data = mdecrypt_generic($td, $decoded_64); 
	mcrypt_generic_deinit($td); 
	mcrypt_module_close($td); 
	return trim($decrypted_data); 
}

 

and i have two page index.php and testing.php

 

index.php

require_once("function.php");
$code = encrypt("L00002");
echo "<a href=\"testing.php?code=".$code."\">click</a>";

 

testing.php

$code = decrypt("L00002");
echo $code;

 

the result before encrypt and decrypt is different for some value, what must i do?

or some body can show me how to encrypt query string but it have same value before encrypt and after decrypt?

 

i have search at google but when i try the value always different for some value.

 

thx

[mmarif4u]

In the testing.php u have to use GET to retrieve the value of code.

Also add ur function to that page.

 

testing.php

<?php
require_once("function.php");
$code=$_GET['code'];
$code1=decrypt($code);
echo $code1;
?>

 

Hope this will help.

[xeonyk]

i have try but the value encrypt and decrypt is different for some value like L00002

when i try L00001 it work good

 

can anyone give me other tutorial?

[mmarif4u]

Oh 1st u hash the keyword with md5 so sorry man its not possible to unhash the md5 hash,

So definitely it will give u the different value.

[xeonyk]

it not work i change my key into string "hehe" it result still same, some value not same when encrypted