/**
* Encrypt a message with a target users' public key
*
* @param string $source Message to encrypt
* @param EncryptionPublicKey $publicKey
* @param boolean $raw Don't hex encode the output?
* @return string
* @throws CryptoException\CannotPerformOperation
*/
public static function seal(string $source, EncryptionPublicKey $publicKey, bool $raw = false) : string
{
if (!$publicKey instanceof EncryptionPublicKey) {
throw new CryptoException\InvalidKey('Argument 2: Expected an instance of EncryptionPublicKey');
}
if (!function_exists('\\Sodium\\crypto_box_seal')) {
throw new CryptoException\CannotPerformOperation('crypto_box_seal is not available');
}
$sealed = \Sodium\crypto_box_seal($source, $publicKey->getRawKeyMaterial());
if ($raw) {
return $sealed;
}
return \Sodium\bin2hex($sealed);
}
/**
* @covers Asymmetric::seal()
* @covers Asymmetric::unseal()
*/
public function testSeal()
{
if (\Sodium\library_version_major() < 7 || \Sodium\library_version_major() == 7 && \Sodium\library_version_minor() < 5) {
$this->markTestSkipped("Your version of libsodium is too old");
}
$alice = KeyFactory::generateEncryptionKeyPair();
$enc_secret = $alice->getSecretKey();
$enc_public = $alice->getPublicKey();
$this->assertEquals(\Sodium\crypto_box_publickey_from_secretkey($enc_secret->getRawKeyMaterial()), $enc_public->getRawKeyMaterial());
$message = 'This is for your eyes only';
$kp = \Sodium\crypto_box_keypair();
$test = \Sodium\crypto_box_seal($message, \Sodium\crypto_box_publickey($kp));
$decr = \Sodium\crypto_box_seal_open($test, $kp);
$this->assertTrue($decr !== false);
$sealed = Asymmetric::seal($message, new EncryptionPublicKey(\Sodium\crypto_box_publickey($kp)));
$opened = Asymmetric::unseal($sealed, new EncryptionSecretKey(\Sodium\crypto_box_secretkey($kp)));
$sealed = Asymmetric::seal($message, $enc_public);
$opened = Asymmetric::unseal($sealed, $enc_secret);
$this->assertEquals($opened, $message);
$sealed_raw = Asymmetric::seal($message, $alice->getPublicKey());
$opened_raw = Asymmetric::unseal($sealed_raw, $alice->getSecretKey());
$this->assertEquals($opened_raw, $message);
}
/**
* Encrypt a message with a target users' public key
*
* @param string $source Message to encrypt
* @param string $publicKey
* @param boolean $raw Don't hex encode the output?
*
* @return string
*/
public static function seal($source, Contract\CryptoKeyInterface $publicKey, $raw = false)
{
if ($publicKey->isPublicKey()) {
if (function_exists('\\Sodium\\crypto_box_seal')) {
$sealed = \Sodium\crypto_box_seal($source, $publicKey->get());
} else {
/**
* Polyfill for libsodium < 1.0.3
*/
// Generate an ephemeral keypair
$eph_kp = \Sodium\crypto_box_keypair();
$eph_secret = \Sodium\crypto_box_secretkey($eph_kp);
$eph_public = \Sodium\crypto_box_publickey($eph_kp);
$seal_pubkey = $publicKey->get();
$box_kp = \Sodium\crypto_box_keypair_from_secretkey_and_publickey($eph_secret, $seal_pubkey);
// Calculate the nonce
$nonce = \Sodium\crypto_generichash($eph_public . $seal_pubkey, null, \Sodium\CRYPTO_BOX_NONCEBYTES);
// Seal the message
$sealed = $eph_public . \Sodium\crypto_box($source, $nonce, $box_kp);
// Don't forget to wipe
\Sodium\memzero($seal_pubkey);
\Sodium\memzero($eph_kp);
\Sodium\memzero($eph_secret);
\Sodium\memzero($eph_public);
\Sodium\memzero($nonce);
\Sodium\memzero($box_kp);
}
if ($raw) {
return $sealed;
}
return \Sodium\bin2hex($sealed);
}
throw new CryptoAlert\InvalidKey('Expected a public key');
}
/**
* Encrypt a message with a target users' public key
*
* @param string $source Message to encrypt
* @param string $publicKey
* @param boolean $raw Don't hex encode the output?
*
* @return string
*/
public static function seal($source, Contract\CryptoKeyInterface $publicKey, $raw = false)
{
if ($publicKey->isPublicKey()) {
if (function_exists('\\Sodium\\crypto_box_seal')) {
$sealed = \Sodium\crypto_box_seal($source, $publicKey->get());
} else {
throw new CryptoException\CannotPerformOperation('crypto_box_seal is not available');
}
if ($raw) {
return $sealed;
}
return \Sodium\bin2hex($sealed);
}
throw new CryptoException\InvalidKey('Expected a public key');
}
/**
* Encrypt a message with a target users' public key
*
* @param HiddenString $plaintext Message to encrypt
* @param EncryptionPublicKey $publicKey Public encryption key
* @param mixed $encoding Which encoding scheme to use?
* @return string Ciphertext
* @throws CannotPerformOperation
* @throws InvalidKey
*/
public static function seal(HiddenString $plaintext, EncryptionPublicKey $publicKey, $encoding = Halite::ENCODE_BASE64URLSAFE) : string
{
if (!$publicKey instanceof EncryptionPublicKey) {
throw new InvalidKey('Argument 2: Expected an instance of EncryptionPublicKey');
}
$sealed = \Sodium\crypto_box_seal($plaintext->getString(), $publicKey->getRawKeyMaterial());
$encoder = Halite::chooseEncoder($encoding);
if ($encoder) {
return $encoder($sealed);
}
return $sealed;
}
