/**
* Encrypt a message using public key encryption.
*
* @param string $message The message to be encrypted.
* @param string $sender_private The senders private key.
* @param string $receiver_public The receivers public key.
* @return string The JSON string for the encrypted message.
* @throws InvalidTypeException
*/
public static function encrypt($message, $sender_private, $receiver_public)
{
# Test to make sure all the required variables are strings.
Helpers::isString($message, 'PublicKeyEncryption', 'encrypt');
Helpers::isString($sender_private, 'PublicKeyEncryption', 'encrypt');
Helpers::isString($receiver_public, 'PublicKeyEncryption', 'encrypt');
# Generate a keypair for the message to be sent.
$messageKeyPair = \Sodium\crypto_box_keypair_from_secretkey_and_publickey(Helpers::hex2bin($sender_private), Helpers::hex2bin($receiver_public));
# Generate the nonce for usage.
$nonce = Entropy::generateNonce();
# Encrypt the message and return it.
return base64_encode(json_encode(['msg' => Helpers::bin2hex(\Sodium\crypto_box($message, $nonce, $messageKeyPair)), 'nonce' => Helpers::bin2hex($nonce)]));
}
/**
* @requires extension libsodium
*/
public function test16BitInteger()
{
$this->assertTrue(is_integer(Entropy::integer16()));
}