| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * |
| * 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.android.internal.net.eap.crypto; |
| |
| import com.android.internal.net.crypto.KeyGenerationUtils; |
| import com.android.internal.net.crypto.KeyGenerationUtils.ByteSigner; |
| |
| import java.security.InvalidKeyException; |
| import java.security.NoSuchAlgorithmException; |
| |
| import javax.crypto.Mac; |
| import javax.crypto.spec.SecretKeySpec; |
| |
| /** |
| * HmacSha256ByteSigner is a {@link ByteSigner} to be used for computing HMAC-SHA-256 values for |
| * specific keys and data. |
| */ |
| public class HmacSha256ByteSigner implements KeyGenerationUtils.ByteSigner { |
| private static final String TAG = HmacSha256ByteSigner.class.getSimpleName(); |
| private static final String MAC_ALGORITHM_STRING = "HmacSHA256"; |
| private static final HmacSha256ByteSigner sInstance = new HmacSha256ByteSigner(); |
| |
| /** |
| * Gets instance of HmacSha256ByteSigner. |
| * |
| * @return HmacSha256ByteSigner instance. |
| */ |
| public static HmacSha256ByteSigner getInstance() { |
| return sInstance; |
| } |
| |
| @Override |
| public byte[] signBytes(byte[] keyBytes, byte[] dataToSign) { |
| try { |
| Mac mac = Mac.getInstance(MAC_ALGORITHM_STRING); |
| mac.init(new SecretKeySpec(keyBytes, MAC_ALGORITHM_STRING)); |
| return mac.doFinal(dataToSign); |
| } catch (NoSuchAlgorithmException | InvalidKeyException ex) { |
| throw new IllegalArgumentException(ex); |
| } |
| } |
| } |