| /* |
| * Copyright (C) 2020 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.ipsec.ike.utils; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.content.Context; |
| import android.net.ConnectivityManager; |
| import android.net.Network; |
| import android.net.NetworkCapabilities; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.net.eap.EapAuthenticator.EapRandomFactory; |
| import com.android.internal.net.ipsec.ike.testmode.DeterministicSecureRandom; |
| |
| import java.security.SecureRandom; |
| |
| /** Factory class that creates a DeterministicSecureRandom when test mode is enabled */ |
| @VisibleForTesting |
| public class RandomnessFactory implements EapRandomFactory { |
| // This constant is mirrored of android.net.NetworkCapabilities.TRANSPORT_TEST due to lack of |
| // @TestApi guarantees in mainline modules |
| public static final int TRANSPORT_TEST = 7; |
| |
| private final boolean mIsTestModeEnabled; |
| |
| /** |
| * Constructor of the RandomnessFactory |
| * |
| * @param context a Context instance |
| * @param callerConfiguredNetwork the caller configured Network. Pass null if caller will use a |
| * default network (@see {@link ConnectivityManager#getActiveNetwork()}) |
| */ |
| public RandomnessFactory(@NonNull Context context, @Nullable Network callerConfiguredNetwork) { |
| if (callerConfiguredNetwork == null) { |
| // Test network can never be a default network. Thus when callerConfiguredNetwork is |
| // null, RandomnessFactory will be used on a default network and will not be in test |
| // mode. |
| mIsTestModeEnabled = false; |
| } else { |
| ConnectivityManager connectManager = |
| context.getSystemService(ConnectivityManager.class); |
| NetworkCapabilities networkCapabilities = |
| connectManager.getNetworkCapabilities(callerConfiguredNetwork); |
| |
| mIsTestModeEnabled = |
| networkCapabilities != null && networkCapabilities.hasTransport(TRANSPORT_TEST); |
| } |
| } |
| |
| /** |
| * Returns a DeterministicSecureRandom instance when test mode is enabled. |
| * |
| * <p>Returns a DeterministicSecureRandom instance when test mode is enabled, otherwise returns |
| * null |
| * |
| * <p>TODO(b/154941518): figure out how to let this method always return a random without |
| * relying on nullability behavior |
| */ |
| @Override |
| public SecureRandom getRandom() { |
| if (mIsTestModeEnabled) { |
| return new DeterministicSecureRandom(); |
| } |
| |
| return null; |
| } |
| } |