#!/usr/local/bin/perl -- -*-fundamental-*-

##  Redirect.pl 
##  Written by Greg Mullane <greg@turnstep.com>
##  Please see http://www.turnstep.com/Spambot/
## 
##  This program redirects a user to another page
##  When used as a POST request, it helps avoid spambots


## Is this properly posted from a web page?
$ENV{"REQUEST_METHOD"} || exit(1);

## Is it a POST? 
if ($ENV{"REQUEST_METHOD"} eq "POST" &&
    $ENV{"CONTENT_TYPE"} && 
    $ENV{"CONTENT_TYPE"} eq "application/x-www-form-urlencoded" &&
    $ENV{"CONTENT_LENGTH"}) {

    $clength = int($ENV{"CONTENT_LENGTH"});

    if ($clength>200) { $clength=200; }
    read(STDIN, $line, $clength);
    if ($line =~ /(.*)=(.*)/) {    
      $url=$2;
      $url =~ s/\+/ /g ;
      $url =~ s/%(..)/pack('c',hex($1))/eg;
    }
    else { exit(1); } ## Oops!
  }

  ## No POST? then exit. We do not want GET requests!
  else {
    exit(1);
  }

## Tell the browser where to go:

$|++;
print "Location: http://$url\n\n";
print "Please see <A HREF=\"http://$url\">http://$url</A>\n";
close(STDOUT);
exit;