core/java/com/android/internal/widget/LockSettingsInternal.java

/*
 * Copyright (C) 2018 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.widget;

import android.annotation.Nullable;
import android.app.admin.PasswordMetrics;

/**
 * LockSettingsService local system service interface.
 *
 * @hide Only for use within the system server.
 */
public abstract class LockSettingsInternal {

    /**
     * Create an escrow token for the current user, which can later be used to unlock FBE
     * or change user password.
     *
     * After adding, if the user currently has lockscreen password, he will need to perform a
     * confirm credential operation in order to activate the token for future use.
     * Once the token is activated, the callback that is passed here is called.   If the user
     * has no secure lockscreen, then the token is activated immediately.
     *
     * @return a unique 64-bit token handle which is needed to refer to this token later.
     */
    public abstract long addEscrowToken(byte[] token, int userId,
            LockPatternUtils.EscrowTokenStateChangeCallback callback);

    /**
     * Remove an escrow token.
     *
     * @return true if the given handle refers to a valid token previously returned from
     * {@link #addEscrowToken}, whether it's active or not. return false otherwise.
     */
    public abstract boolean removeEscrowToken(long handle, int userId);

    /**
     * Check if the given escrow token is active or not. Only active token can be used to call
     * {@link #setLockCredentialWithToken} and {@link #unlockUserWithToken}
     */
    public abstract boolean isEscrowTokenActive(long handle, int userId);

    /**
     * Set the lock credential.
     *
     * @return true if password is set.
     */
    public abstract boolean setLockCredentialWithToken(LockscreenCredential credential,
            long tokenHandle, byte[] token, int userId);

    public abstract boolean unlockUserWithToken(long tokenHandle, byte[] token, int userId);

    /**
     * Returns PasswordMetrics object corresponding to the given user's lockscreen password.
     * If the user has a password but its metrics isn't known yet (for example if the device
     * has not been unlocked since boot), this method will return {@code null}.
     * If the user has no password, a default PasswordMetrics (PASSWORD_QUALITY_UNSPECIFIED)
     * will be returned.
     *
     * Calling this method on a managed profile user with unified challenge is undefined.
     *
     * @param userHandle the user for whom to provide metrics.
     * @return the user password metrics.
     */
    public abstract @Nullable PasswordMetrics getUserPasswordMetrics(int userHandle);
}