PHP encryption and decryption class implementation code

Class crypt{

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protected $key = ""; Public

Private function keyed ($txt, $encrypt _key)

{

$encrypt _key = MD5 ($encrypt _key);

$ctr = 0;

$tmp = "";

for ($i =0; $i

{

if ($ctr ==strlen ($encrypt _key)) {

$ctr = 0;

}

$tmp. = substr ($txt, $i, 1) ^ substr ($encrypt _key, $ctr, 1);

$ctr + +;

}

return $tmp;

}

Public function Encrypt ($txt, $key = "")

{

if (empty ($key)) {

$key = $this->key;

}

Srand (Double) microtime () *1000000);

$encrypt _key = MD5 (rand (0,32000));

$ctr = 0;

$tmp = "";

for ($i =0; $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 $this->keyed ($tmp, $key);

}

Public function Decrypt ($txt, $key = "")

{

if (empty ($key)) {

$key = $this->key;

}

$txt = $this->keyed ($txt, $key);

$tmp = "";

for ($i =0; $i

{

$MD 5 = substr ($txt, $i, 1);

$i + +;

$tmp. = (substr ($txt, $i, 1) ^ $md 5);

}

return $tmp;

}

Public Function Setkey ($key)

{

if (empty ($key)) {

return null;

}

$this->key= $key;

}

Public Function Getkey ()

{

return $this->key;

}

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}

$string = "http://www.52blogger.com";

$crypt = new Crypt ();

$crypt->setkey ("http://www.52blogger.com");

$enc _text = $crypt->encrypt ($string, $crypt->getkey ());

$dec _text = $crypt->decrypt ($enc _text, $crypt->getkey ());

echo Before encryption: $string

n ";

echo after encryption: $enc _text

n ";

echo "After decryption: $dec _text n";

?>

Execution results:

Pre-encryption: http://www.52blogger.com

After encryption: Hszq ' z* kp~y (Wpvs=6q3gzbr5qkhtz (f=zm

After decryption: http://www.52blogger.com