1 /*
2  * Copyright (C) 2023 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.net.module.util;
18 
19 /**
20  * Class to centralize feature version control that requires a specific module or a specific
21  * module version.
22  * @hide
23  */
24 public class FeatureVersions {
25     /**
26      * This constant is used to do bitwise shift operation to create module ids.
27      * The module version is composed with 9 digits which is placed in the lower 36 bits.
28      */
29     private static final int MODULE_SHIFT = 36;
30     /**
31      * The bitmask to do bitwise-and(i.e. {@code &}) operation to get the module id.
32      */
33     public static final long MODULE_MASK = 0xFF0_0000_0000L;
34     /**
35      * The bitmask to do bitwise-and(i.e. {@code &}) operation to get the module version.
36      */
37     public static final long VERSION_MASK = 0x00F_FFFF_FFFFL;
38     public static final long CONNECTIVITY_MODULE_ID = 0x01L << MODULE_SHIFT;
39     public static final long NETWORK_STACK_MODULE_ID = 0x02L << MODULE_SHIFT;
40     // CLAT_ADDRESS_TRANSLATE is a feature of the network stack, which doesn't throw when system
41     // try to add a NAT-T keepalive packet filter with v6 address, introduced in version
42     // M-2023-Sept on July 3rd, 2023.
43     public static final long FEATURE_CLAT_ADDRESS_TRANSLATE =
44             NETWORK_STACK_MODULE_ID + 34_09_00_000L;
45 
46     // IS_UID_NETWORKING_BLOCKED is a feature in ConnectivityManager,
47     // which provides an API to access BPF maps to check whether the networking is blocked
48     // by BPF for the given uid and conditions, introduced in version M-2024-Feb on Nov 6, 2023.
49     public static final long FEATURE_IS_UID_NETWORKING_BLOCKED =
50             CONNECTIVITY_MODULE_ID + 34_14_00_000L;
51 }
52