GEO Source Code

A neat, simple and secure encrypt decrypt function that is URL safe. (meaning you can transport the encrypted string through a http get or post). Since this is based on the base64_encode() function, you should expect the encoded data to take about 33% more space than the original data.

Usage:

Code: Select all

encrypt(’Welcome to GeoSourceCode.com’,’secretkey’);

This will show:

0NjRxuHS2YvZ6JPVy-LJ3czX8qHU1dk=

Now, let’s reverse it.

Code: Select all

decrypt(’0NjRxuHS2YvZ6JPVy-LJ3czX8qHU1dk=’,’secretkey’);

This will show:

Welcome to GeoSourceCode.com

See, it works! And now the code..

Code: Select all

<?
   function encrypt($sData, $sKey)
   {
      $sResult = '';

      for($i = 0; $i < strlen($sData); $i ++)
      {
         $sChar    = substr($sData, $i, 1);
         $sKeyChar = substr($sKey, ($i % strlen($sKey)) - 1, 1);
         $sChar    = chr(ord($sChar) + ord($sKeyChar));
         $sResult .= $sChar;
      }

      return encode_base64($sResult);
   }

   function decrypt($sData, $sKey)
   {
      $sResult = '';
      $sData   = decode_base64($sData);

      for($i = 0; $i < strlen($sData); $i ++)
      {
         $sChar    = substr($sData, $i, 1);
         $sKeyChar = substr($sKey, ($i % strlen($sKey)) - 1, 1);
         $sChar    = chr(ord($sChar) - ord($sKeyChar));
         $sResult .= $sChar;
      }

      return $sResult;
   }

   function encode_base64($sData)
   {
      $sBase64 = base64_encode($sData);

      return strtr($sBase64, '+/', '-_');
   }

   function decode_base64($sData)
   {
      $sBase64 = strtr($sData, '-_', '+/');

      return base64_decode($sBase64);
   }
?>


And if you may be curious to know what are the different characters that the encrypt() function may return, here is the list:
A-Z
a-z
0-9
-
_
=

Therefore your encrypted data will be URL and filename safe.

source code a algorithm AES or RSA with PHP??

RSA is a very important encryption algorithm. It allows securely transmitting data encrypted with a private key that can only be decrypted with a public key.

There is class provides a pure PHP implementation of the RSA encryption algorithm, thus without relying on any PHP cryptography extensions.

Note:
php-rsa.zip is structured based implementation of RSA Algorithm

rsa-class.zip is class based implementation of RSA Algorithm