function decrypt($message, $private_key, $modulus, $keylength) { $number = Rsa::binary_to_number($message); $decrypted = Rsa::pow_mod($number, $private_key, $modulus); $result = Rsa::number_to_binary($decrypted, $keylength / 8); return Rsa::remove_PKCS1_padding($result, $keylength / 8); }