source: trunk/phpgwapi/inc/adodb/session/crypt.inc.php @ 2

<?php
//       Session Encryption by Ari Kuorikoski <ari.kuorikoski@finebyte.com>
class MD5Crypt{
                function keyED($txt,$encrypt_key)
                {
                                $encrypt_key = md5($encrypt_key);
                                $ctr=0;
                                $tmp = "";
                                for ($i=0;$i<strlen($txt);$i++){
                                                if ($ctr==strlen($encrypt_key)) $ctr=0;
                                                $tmp.= substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1);
                                                $ctr++;
                                }
                                return $tmp;
                }

                function Encrypt($txt,$key)
                {
                                srand((double)microtime()*1000000);
                                $encrypt_key = md5(rand(0,32000));
                                $ctr=0;
                                $tmp = "";
                                for ($i=0;$i<strlen($txt);$i++)
                                {
                                if ($ctr==strlen($encrypt_key)) $ctr=0;
                                $tmp.= substr($encrypt_key,$ctr,1) .
                                (substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1));
                                $ctr++;
                                }
                                return base64_encode($this->keyED($tmp,$key));
                }

                function Decrypt($txt,$key)
                {
                                $txt = $this->keyED(base64_decode($txt),$key);
                                $tmp = "";
                                for ($i=0;$i<strlen($txt);$i++){
                                                $md5 = substr($txt,$i,1);
                                                $i++;
                                                $tmp.= (substr($txt,$i,1) ^ $md5);
                                }
                                return $tmp;
                }

                function RandPass()
                {
                                $randomPassword = "";
                                srand((double)microtime()*1000000);
                                for($i=0;$i<8;$i++)
                                {
                                                $randnumber = rand(48,120);

                                                while (($randnumber >= 58 && $randnumber <= 64) || ($randnumber >= 91 && $randnumber <= 96))
                                                {
                                                                $randnumber = rand(48,120);
                                                }

                                                $randomPassword .= chr($randnumber);
                                }
                                return $randomPassword;
                }

}
?>