java/src/test/java/com/google/crypto/tink/hybrid/EciesAeadHkdfPrivateKeyManagerTest.java

// Copyright 2017 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
////////////////////////////////////////////////////////////////////////////////

package com.google.crypto.tink.hybrid;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;

import com.google.crypto.tink.Config;
import com.google.crypto.tink.HybridDecrypt;
import com.google.crypto.tink.HybridEncrypt;
import com.google.crypto.tink.KeyManager;
import com.google.crypto.tink.KeyManagerImpl;
import com.google.crypto.tink.KeysetHandle;
import com.google.crypto.tink.PrivateKeyManager;
import com.google.crypto.tink.PrivateKeyManagerImpl;
import com.google.crypto.tink.TestUtil;
import com.google.crypto.tink.aead.AeadKeyTemplates;
import com.google.crypto.tink.proto.EcPointFormat;
import com.google.crypto.tink.proto.EciesAeadHkdfKeyFormat;
import com.google.crypto.tink.proto.EciesAeadHkdfParams;
import com.google.crypto.tink.proto.EciesAeadHkdfPrivateKey;
import com.google.crypto.tink.proto.EllipticCurveType;
import com.google.crypto.tink.proto.HashType;
import com.google.crypto.tink.proto.KeyData;
import com.google.crypto.tink.proto.KeyStatusType;
import com.google.crypto.tink.proto.KeyTemplate;
import com.google.crypto.tink.proto.Keyset.Key;
import com.google.crypto.tink.proto.OutputPrefixType;
import com.google.crypto.tink.subtle.Random;
import org.junit.BeforeClass;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests for EciesAeadHkdfPrivateKeyManager. */
@RunWith(JUnit4.class)
public class EciesAeadHkdfPrivateKeyManagerTest {
  @BeforeClass
  public static void setUp() throws Exception {
    Config.register(HybridConfig.TINK_1_0_0);
  }

  @Test
  public void testNewKey() throws Exception {
    EllipticCurveType curve = EllipticCurveType.NIST_P384;
    HashType hashType = HashType.SHA256;
    EcPointFormat pointFormat = EcPointFormat.UNCOMPRESSED;
    KeyTemplate demKeyTemplate = AeadKeyTemplates.AES128_CTR_HMAC_SHA256;

    byte[] salt = "some salt".getBytes("UTF-8");
    EciesAeadHkdfParams params =
        HybridKeyTemplates.createEciesAeadHkdfParams(
            curve, hashType, pointFormat, demKeyTemplate, salt);

    PrivateKeyManager<HybridDecrypt> manager =
        new PrivateKeyManagerImpl<>(
            new EciesAeadHkdfPrivateKeyManager(),
            new EciesAeadHkdfPublicKeyManager(),
            HybridDecrypt.class);
    EciesAeadHkdfPrivateKey keyProto =
        (EciesAeadHkdfPrivateKey)
            manager.newKey(EciesAeadHkdfKeyFormat.newBuilder().setParams(params).build());
    assertEquals(params, keyProto.getPublicKey().getParams());

    Key primaryPriv =
        TestUtil.createKey(
            TestUtil.createKeyData(
                keyProto,
                new EciesAeadHkdfPrivateKeyManager().getKeyType(),
                KeyData.KeyMaterialType.ASYMMETRIC_PRIVATE),
            8,
            KeyStatusType.ENABLED,
            OutputPrefixType.RAW);
    Key primaryPub =
        TestUtil.createKey(
            TestUtil.createKeyData(
                keyProto.getPublicKey(),
                new EciesAeadHkdfPublicKeyManager().getKeyType(),
                KeyData.KeyMaterialType.ASYMMETRIC_PUBLIC),
            42,
            KeyStatusType.ENABLED,
            OutputPrefixType.RAW);
    KeysetHandle keysetHandlePub = TestUtil.createKeysetHandle(TestUtil.createKeyset(primaryPub));
    KeysetHandle keysetHandlePriv = TestUtil.createKeysetHandle(TestUtil.createKeyset(primaryPriv));
    HybridEncrypt hybridEncrypt = HybridEncryptFactory.getPrimitive(keysetHandlePub);
    HybridDecrypt hybridDecrypt = HybridDecryptFactory.getPrimitive(keysetHandlePriv);
    byte[] plaintext = Random.randBytes(20);
    byte[] contextInfo = Random.randBytes(20);
    byte[] ciphertext = hybridEncrypt.encrypt(plaintext, contextInfo);
    assertArrayEquals(plaintext, hybridDecrypt.decrypt(ciphertext, contextInfo));
  }

  /** Tests that a public key is extracted properly from a private key. */
  @Test
  public void testGetPublicKeyData() throws Exception {
    KeysetHandle privateHandle =
        KeysetHandle.generateNew(
            HybridKeyTemplates.ECIES_P256_HKDF_HMAC_SHA256_AES128_CTR_HMAC_SHA256);
    KeyData privateKeyData = TestUtil.getKeyset(privateHandle).getKey(0).getKeyData();
    PrivateKeyManager<HybridDecrypt> privateManager =
        new PrivateKeyManagerImpl<>(
            new EciesAeadHkdfPrivateKeyManager(),
            new EciesAeadHkdfPublicKeyManager(),
            HybridDecrypt.class);
    KeyData publicKeyData = privateManager.getPublicKeyData(privateKeyData.getValue());
    assertEquals(new EciesAeadHkdfPublicKeyManager().getKeyType(), publicKeyData.getTypeUrl());
    assertEquals(KeyData.KeyMaterialType.ASYMMETRIC_PUBLIC, publicKeyData.getKeyMaterialType());
    EciesAeadHkdfPrivateKey privateKey =
        EciesAeadHkdfPrivateKey.parseFrom(privateKeyData.getValue());
    assertArrayEquals(
        privateKey.getPublicKey().toByteArray(), publicKeyData.getValue().toByteArray());

    KeyManager<HybridEncrypt> publicManager =
        new KeyManagerImpl<>(new EciesAeadHkdfPublicKeyManager(), HybridEncrypt.class);
    HybridEncrypt hybridEncrypt = publicManager.getPrimitive(publicKeyData.getValue());
    HybridDecrypt hybridDecrypt = privateManager.getPrimitive(privateKeyData.getValue());
    byte[] message = Random.randBytes(20);
    byte[] contextInfo = Random.randBytes(20);
    assertArrayEquals(
        message, hybridDecrypt.decrypt(hybridEncrypt.encrypt(message, contextInfo), contextInfo));
  }
}