encryption-runner/src/android/car/encryptionrunner/EncryptionRunnerFactory.java

/*
 * 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 android.car.encryptionrunner;

import androidx.annotation.IntDef;
import androidx.annotation.VisibleForTesting;

/**
 * Factory that creates encryption runner.
 */
public class EncryptionRunnerFactory {

    private EncryptionRunnerFactory() {
        // prevent instantiation.
    }

    @IntDef({EncryptionRunnerType.UKEY2, EncryptionRunnerType.OOB_UKEY2})
    public @interface EncryptionRunnerType {
        /** Use Ukey2 as underlying key exchange. */
        int UKEY2 = 0;
        /** Use Ukey2 and an out of band channel as underlying key exchange. */
        int OOB_UKEY2 = 1;
    }

    /**
     * Creates a new {@link EncryptionRunner} based on {@param type}.
     */
    public static EncryptionRunner newRunner(@EncryptionRunnerType int type) {
        switch (type) {
            case EncryptionRunnerType.UKEY2:
                return new Ukey2EncryptionRunner();
            case EncryptionRunnerType.OOB_UKEY2:
                return new OobUkey2EncryptionRunner();
            default:
                throw new IllegalArgumentException("Unknown EncryptionRunnerType: " + type);
        }
    }

    /**
     * Creates a new {@link EncryptionRunner}.
     *
     * @deprecated Use {@link #newRunner(int)} instead.
     */
    @Deprecated
    public static EncryptionRunner newRunner() {
        return newRunner(EncryptionRunnerType.UKEY2);
    }

    /**
     * Creates a new {@link EncryptionRunner} that doesn't actually do encryption but is useful
     * for testing.
     */
    @VisibleForTesting
    public static EncryptionRunner newFakeRunner() {
        return new FakeEncryptionRunner();
    }

    /**
     * Creates a new {@link EncryptionRunner} that doesn't actually do encryption but is useful
     * for out of band association testing.
     */
    @VisibleForTesting
    public static EncryptionRunner newOobFakeRunner() {
        return new OobFakeEncryptionRunner();
    }
}