com.google.crypto.tink.aead.subtle

Class AesGcmSiv

java.lang.Object

com.google.crypto.tink.aead.subtle.AesGcmSiv

All Implemented Interfaces:

Aead

@Alpha
public final class AesGcmSiv
extends Object
implements Aead

This primitive implements AES-GCM-SIV (as defined in RFC 8452) using JCE.

This encryption mode is intended for authenticated encryption with associated data. A major security problem with AES-GCM is that reusing the same nonce twice leaks the authentication key. AES-GCM-SIV on the other hand has been designed to avoid this vulnerability.

This encryption requires a JCE provider that supports the AES/GCM-SIV/NoPadding transformation such as Conscrypt. using JCE.

Constructor Summary

Constructors

Constructor and Description
AesGcmSiv(byte[] key)

Method Summary

Modifier and Type	Method and Description
byte[]	decrypt(byte[] ciphertext, byte[] associatedData) On Android KitKat (API level 19) this method does not support non null or non empty associatedData.
byte[]	encrypt(byte[] plaintext, byte[] associatedData) On Android KitKat (API level 19) this method does not support non null or non empty associatedData.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AesGcmSiv

public AesGcmSiv(byte[] key)
          throws GeneralSecurityException

Throws:

GeneralSecurityException

Method Detail

encrypt

public byte[] encrypt(byte[] plaintext,
                      byte[] associatedData)
               throws GeneralSecurityException

On Android KitKat (API level 19) this method does not support non null or non empty associatedData. It might not work at all in older versions.

Specified by:

encrypt in interface Aead

Parameters:

plaintext - the plaintext to be encrypted. It must be non-null, but can also be an empty (zero-length) byte array

associatedData - associated data to be authenticated, but not encrypted. Associated data is optional, so this parameter can be null. In this case the null value is equivalent to an empty (zero-length) byte array. For successful decryption the same associatedData must be provided along with the ciphertext.

Returns:

resulting ciphertext

Throws:

GeneralSecurityException

decrypt

public byte[] decrypt(byte[] ciphertext,
                      byte[] associatedData)
               throws GeneralSecurityException

On Android KitKat (API level 19) this method does not support non null or non empty associatedData. It might not work at all in older versions.

Specified by:

decrypt in interface Aead

Parameters:

ciphertext - the plaintext to be decrypted. It must be non-null.

associatedData - associated data to be authenticated. For successful decryption it must be the same as associatedData used during encryption. Can be null, which is equivalent to an empty (zero-length) byte array.

Returns:

resulting plaintext

Throws:

GeneralSecurityException