[RESOLVED] Obfuscation Routine from PERL To PHP

DaleRobbins

I am currently maintaining a script that uses the following method in PERL to obfuscate email addresses passed as a query string through a URL. Using the same method, I simply need the ability to use PHP to decode the same string that has been encoded with PERL. Got any ideas?


#!/usr/bin/perl

print "Content-type: text/html\n\n";

$email = "wackyman\@whatever.com";

# Encrypt
$email =~ tr/a-zA-Z/s-za-rS-ZA-R/;
$email =~ s/(.)/ sprintf('%02x',ord($1)) /ge ;

print "Encoded Email: $email \n";

# Decrypted
$email =~ s/([0-9A-Fa-f]{2})/ sprintf("%c",hex($1)) /ge ;
$email =~ tr/s-za-rS-ZA-R/a-zA-Z/;

print "<br>\n<br>\n";

print "Decoded Email: $email";

NogDog

I think this will do it, but I'll leave it to you to test against your Perl script, to see if the encodings are the same. (I went OOP just to keep things straight in my mind, rather than try to imitate the terseness of Perl. 🙂 )

<?php
class Obfuscator
{
   /**
    * @var array Transliteration array
    */
   private $trans = array();
   /**
    * Constructor
    * @return void
    */
   public function __construct()
   {
      // build the transliteration array
      $orig = array_merge(range('a', 'z'), range('A', 'Z'));
      $trans = array_merge(
         range('s', 'z'),
         range('a', 'r'),
         range('S', 'Z'),
         range('A', 'R')
      );
      $this->trans = array_combine($orig, $trans);
   }
   /**
    * Encode a string
    * @return string
    * @param string $str
    */
   public function encode($str)
   {
      $result = '';
      for($i=0, $len=strlen($str); $i<$len; $i++) {
         $result .= sprintf(
            '%02x',
            ord((isset($this->trans[$str[$i]])) ? $this->trans[$str[$i]] : $str[$i])
         );
      }
      return $result;
   }
   /**
    * Decode a string
    * @return string
    * @param string $str
    */
   public function decode($str)
   {
      $result = '';
      for($i=0,$len=strlen($str); $i<$len; $i+=2){
         $char = chr(hexdec(substr($str, $i, 2)));
         $result .= (in_array($char, $this->trans)) ?
                     array_search($char, $this->trans) : $char;
      }
      return $result;
   }
}

// TEST:
$test = new Obfuscator();
$encoded = $test->encode('Nog@Dog.com');
$decoded = $test->decode($encoded);
echo "<pre>$encoded
$decoded</pre>";

Weedpacket

Assuming that the email doesn't contain any control characters (which a valid email wouldn't contain anyway):

function encode($email)
{
	$email = strtr($email, 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
                           'stuvwxyzabcdefghijklmnopqrSTUVWXYZABCDEFGHIJKLMNOPQR');
	$email = array_map('dechex', array_map('ord', str_split($email)));
	return join('', $email);
}

function decode($email)
{
	$email = join('', array_map('chr', array_map('hexdec', str_split($email, 2))));
	return strtr($email, 'stuvwxyzabcdefghijklmnopqrSTUVWXYZABCDEFGHIJKLMNOPQR',
                         'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ');
}

DaleRobbins

This worked wonderfully! Does exactly what I needed. THANK YOU SO MUCH!!!!

In reply to the other comments, No, there will be no control characters in the string... only email.

Thanks again for all your input!!!!

NogDog

Weedpacket;10981732 wrote:

Assuming that the email doesn't contain any control characters (which a valid email wouldn't contain anyway):

function encode($email)
{
	$email = strtr($email, 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
                           'stuvwxyzabcdefghijklmnopqrSTUVWXYZABCDEFGHIJKLMNOPQR');
	$email = array_map('dechex', array_map('ord', str_split($email)));
	return join('', $email);
}

function decode($email)
{
	$email = join('', array_map('chr', array_map('hexdec', str_split($email, 2))));
	return strtr($email, 'stuvwxyzabcdefghijklmnopqrSTUVWXYZABCDEFGHIJKLMNOPQR',
                         'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ');
}

Well crap: I tried googling for something to indicate what the PHP corollary was to the Perl "tr" operator and couldn't find anything. (I figured there was likely to be one, but just couldn't find it.)