1 /* 2 * Copyright (C) 2022 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.server.connectivity.mdns.internal; 18 19 import android.annotation.NonNull; 20 import android.net.LinkAddress; 21 import android.os.Handler; 22 import android.system.OsConstants; 23 import android.util.Log; 24 25 import com.android.net.module.util.SharedLog; 26 import com.android.net.module.util.ip.NetlinkMonitor; 27 import com.android.net.module.util.netlink.NetlinkConstants; 28 import com.android.net.module.util.netlink.NetlinkMessage; 29 import com.android.net.module.util.netlink.RtNetlinkAddressMessage; 30 import com.android.net.module.util.netlink.StructIfaddrMsg; 31 import com.android.server.connectivity.mdns.AbstractSocketNetlink; 32 import com.android.server.connectivity.mdns.MdnsSocketProvider; 33 34 /** 35 * The netlink monitor for MdnsSocketProvider. 36 */ 37 public class SocketNetlinkMonitor extends NetlinkMonitor implements AbstractSocketNetlink { 38 39 public static final String TAG = SocketNetlinkMonitor.class.getSimpleName(); 40 41 @NonNull 42 private final MdnsSocketProvider.NetLinkMonitorCallBack mCb; SocketNetlinkMonitor(@onNull final Handler handler, @NonNull SharedLog log, @NonNull final MdnsSocketProvider.NetLinkMonitorCallBack cb)43 public SocketNetlinkMonitor(@NonNull final Handler handler, 44 @NonNull SharedLog log, 45 @NonNull final MdnsSocketProvider.NetLinkMonitorCallBack cb) { 46 super(handler, log, TAG, OsConstants.NETLINK_ROUTE, 47 NetlinkConstants.RTMGRP_IPV4_IFADDR | NetlinkConstants.RTMGRP_IPV6_IFADDR); 48 mCb = cb; 49 } 50 @Override processNetlinkMessage(NetlinkMessage nlMsg, long whenMs)51 public void processNetlinkMessage(NetlinkMessage nlMsg, long whenMs) { 52 if (nlMsg instanceof RtNetlinkAddressMessage) { 53 processRtNetlinkAddressMessage((RtNetlinkAddressMessage) nlMsg); 54 } 55 } 56 57 /** 58 * Process the RTM_NEWADDR and RTM_DELADDR netlink message. 59 */ processRtNetlinkAddressMessage(RtNetlinkAddressMessage msg)60 private void processRtNetlinkAddressMessage(RtNetlinkAddressMessage msg) { 61 final StructIfaddrMsg ifaddrMsg = msg.getIfaddrHeader(); 62 final LinkAddress la = new LinkAddress(msg.getIpAddress(), ifaddrMsg.prefixLen, 63 msg.getFlags(), ifaddrMsg.scope); 64 if (!la.isPreferred()) { 65 // Skip the unusable ip address. 66 return; 67 } 68 switch (msg.getHeader().nlmsg_type) { 69 case NetlinkConstants.RTM_NEWADDR: 70 mCb.addOrUpdateInterfaceAddress(ifaddrMsg.index, la); 71 break; 72 case NetlinkConstants.RTM_DELADDR: 73 mCb.deleteInterfaceAddress(ifaddrMsg.index, la); 74 break; 75 default: 76 Log.e(TAG, "Unknown rtnetlink address msg type " + msg.getHeader().nlmsg_type); 77 } 78 } 79 80 @Override isSupported()81 public boolean isSupported() { 82 return true; 83 } 84 85 @Override startMonitoring()86 public void startMonitoring() { 87 this.start(); 88 } 89 90 @Override stopMonitoring()91 public void stopMonitoring() { 92 this.stop(); 93 } 94 } 95