How to check if my encryption is correct

Question

Hi I have this code that encrypts password and/or username. I'm trying to learn a better way of coding so I ask this question and sorry If this is one of those elementary questions.

I followed this steps stated in another post This one and I want to display (for testing purposes only if what I did was right) It does not need to be username or password, just a plain text inserted in an input box will do as long as I can see if what i entered is encrypted using my code. Please help me out. Stuck for like forever in this scenario.

Now here's my code.

MCrypt.php(just copied it)

<?php 

    class MCrypt
    {
            private $iv = 'fedcba9876543210'; #Same as in JAVA
            private $key = '0123456789abcdef'; #Same as in JAVA


            function __construct()
            {
            }

            function encrypt($str) {

              //$key = $this->hex2bin($key);    
              $iv = $this->iv;

              $td = mcrypt_module_open('rijndael-128', '', 'cbc', $iv);

              mcrypt_generic_init($td, $this->key, $iv);
              $encrypted = mcrypt_generic($td, $str);

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

              return bin2hex($encrypted);
            }

            function decrypt($code) {
              //$key = $this->hex2bin($key);
              $code = $this->hex2bin($code);
              $iv = $this->iv;

              $td = mcrypt_module_open('rijndael-128', '', 'cbc', $iv);

              mcrypt_generic_init($td, $this->key, $iv);
              $decrypted = mdecrypt_generic($td, $code);

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

              return utf8_encode(trim($decrypted));
            }

            protected function hex2bin($hexdata) {
              $bindata = '';

              for ($i = 0; $i < strlen($hexdata); $i += 2) {
                    $bindata .= chr(hexdec(substr($hexdata, $i, 2)));
              }

              return $bindata;
            }

    }
?>

Here's my submit .php which I don't know if it's correct or not but when I try it show these error

Notice: Use of undefined constant MCrypt - assumed 'MCrypt' in    C:\xampp\htdocs\HSC\submit.php on line 2
Notice: Use of undefined constant php - assumed 'php' in C:\xampp\htdocs\HSC\submit.php   on line 2
Warning: include(MCryptphp): failed to open stream: No such file or directory in C:\xampp\htdocs\HSC\submit.php on line 2
Warning: include(): Failed opening 'MCryptphp' for inclusion (include_path='.;C:\xampp\php\PEAR') in C:\xampp\htdocs\HSC\submit.php on line 2
Fatal error: Class 'MCrypt' not found in C:\xampp\htdocs\HSC\submit.php on line 4

Here's my submit.php

<?php
include(MCrypt.php);

$mcrypt = new MCrypt();
#Encrypt
$encrypted = $mcrypt->encrypt('fruit1');
?>

and my index.php

<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<form action="submit.php">
<input type="text" id="fruit1">
<input type="text" id="fruit2">
<input type="submit" id="submitfruit" name="clickme">
</form>
</body>
</html>

Thanks for the answer. Anyways I found another solution for this. — user3754307, Jun 19 '14 at 17:26

score 1 · Answer 1 · answered Aug 18 '15 at 14:29

Hi I have this code that encrypts password and/or username.

Your first sentence violates basic cryptography concepts.

I'm trying to learn a better way of coding so I ask this question and sorry If this is one of those elementary questions.

As somewhat of a PHP cryptography expert, a better way of coding when it comes to cryptography is to use a reputable and well-studied library instead of writing your own.

See defuse/php-encryption for basic string encryption and password_hash()/password_verify() for storing passwords properly.

As for the code you copied and pasted, it's using hard-coded IVs for CBC mode (massive operational cryptography failure), and failing to apply message authentication to the encryption. Don't use it for anything ever.

How to check if my encryption is correct

1 Answers1