mcrypt functions

[axman505]

I am trying to code a function to encyrpt and one to decrypt, however im having problems on the decrypt.

<?php
function encrypt($stringIn) {
   /* Open the cipher */
   $td = mcrypt_module_open('tripledes', '', 'ofb', '');
   /* Create the IV and determine the keysize length, used MCRYPT_RAND
     * on Windows instead */
   $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_DEV_RANDOM);
   $ks = mcrypt_enc_get_key_size($td);
   /* Create key */
   $key = substr(md5('monkey'), 0, $ks);
   /* Intialize encryption */
   mcrypt_generic_init($td, $key, $iv);
   /* Encrypt data */
   $encrypted = mcrypt_generic($td, $stringIn);
   /* Terminate encryption handler */
   mcrypt_generic_deinit($td);
   mcrypt_module_close($td);
   return $encrypted;   
}
 function decrypt($stringIn) {
    /* Open the cipher */
   $td = mcrypt_module_open('tripledes', '', 'ofb', '');
   /* Create the IV and determine the keysize length, used MCRYPT_RAND
     * on Windows instead */
   $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_DEV_RANDOM);
   $ks = mcrypt_enc_get_key_size($td);
      /* Create key */
   $key = substr(md5('monkey'), 0, $ks);
    /* Initialize encryption module for decryption */
   mcrypt_generic_init($td, $key, $iv);
   /* Decrypt encrypted string */
   $decrypted = mdecrypt_generic($td, $stringIn);
   /* Terminate decryption handle and close module */
   mcrypt_generic_deinit($td);
   mcrypt_module_close($td);
   /* Show string */
   return $decrypted;
}
$test = encrypt("I love CHeese");
print "<p>$test</p>";
$test1 = decrypt($test);
print "<p>$test1</p>";
 

?>