Cannot get encryption class to work - php

Question

I cannot get an encryption class to work (it's in a seperate file in the classes folder). The code for the class is:
class SymmetricCrypt
{
// Encryption/decryption key.
private static $msSecretKey = "Hello";
// The initialisation vector.
private static $msHexaIv = "c7098adc8d6128b5d4b4f7b2fe7f7f05";
// Use the Rijndael Algorithm.
private static $msCipherAlgorithm = MCRYPT_RIJNDAEL_128;
public static function Encrypt($plainString)
{
$binary_iv = pack("H*", SymmetricCrypt::$msHexaIv);
// Encrypt source.
$binary_encrypted_string = mcrypt_encrypt(SymmetricCrypt::$msCipherAlgorithm, SymmetricCrypt::$msSecretKey, $plainString, MCRYPT_MODE_CBC, $binary_iv);
// Convert $binary_encrypted_string to hexadeciaml format.
$hexa_encrypted_string = bin2hex($binary_encrypted_string);
return $hexa_encrypted_string;
}
public static function Decrypt($encryptedString)
{
$binary_iv = pack("H*", SymmetricCrypt::$msHexaIv);
// Convert string in hexadecimal to byte array.
$binary_encrypted_string = pack("H*", $encryptedString);
// Decrypt $binary_encrypted_string,
$decrypted_string = mcrypt_decrypt(SymmetricCrypt::$msCipherAlgorithm, SymmetricCrypt::$msSecretKey, $binary_encrypted_string, MCRYPT_MODE_CBC, $binary_iv);
return $decrypted_string;
}
}
This is how I am calling the class:
require_once 'classes/symmetric_crypt.php';
$sc = new SymmetricCrypt();
$password = "password";
$ec_password = $sc->Encrypt($password);
... insert into database.
If I echo the contents of $password, then it displays "password". If I echo $ec_password, it returns nothing.
I've used it before on a different project on a different server. Could it be something server-related? Any other ideas?
Thanks,
Adrian

Answer 1

Works here.
Two notes:
Your initialization vectors should not be reused. Otherwise, it gets easier to find the encryption key (see WEP).
Like premiso saids, you should not stored store passwords as decryptable strings. Use salted hashes with strong hash functions (not MD5!).