ApfFilter.java revision 0668a61d82a424fb3714b6222f0e4213c18fc7b1
1578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen/* 2578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * Copyright (C) 2016 The Android Open Source Project 3578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * 4578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * Licensed under the Apache License, Version 2.0 (the "License"); 5578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * you may not use this file except in compliance with the License. 6578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * You may obtain a copy of the License at 7578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * 8578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * http://www.apache.org/licenses/LICENSE-2.0 9578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * 10578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * Unless required by applicable law or agreed to in writing, software 11578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * distributed under the License is distributed on an "AS IS" BASIS, 12578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * See the License for the specific language governing permissions and 14578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * limitations under the License. 15578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen */ 16578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 17f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensenpackage android.net.apf; 18578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 19578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport static android.system.OsConstants.*; 20578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 21647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichiimport android.os.SystemClock; 227d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichiimport android.net.LinkAddress; 23a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensenimport android.net.LinkProperties; 24578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.net.NetworkUtils; 25578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.net.apf.ApfGenerator; 26578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.net.apf.ApfGenerator.IllegalInstructionException; 27578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.net.apf.ApfGenerator.Register; 28f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensenimport android.net.ip.IpManager; 294fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichiimport android.net.metrics.ApfProgramEvent; 30647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichiimport android.net.metrics.ApfStats; 314fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichiimport android.net.metrics.IpConnectivityLog; 32cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichiimport android.net.metrics.RaEvent; 33578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.system.ErrnoException; 34578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.system.Os; 35578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.system.PacketSocketAddress; 364fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichiimport android.text.format.DateUtils; 37578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.util.Log; 38578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport android.util.Pair; 39578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 40dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensenimport com.android.internal.annotations.GuardedBy; 419132f34976f16a626c2ec1d3d90624d71e054346Paul Jensenimport com.android.internal.annotations.VisibleForTesting; 42578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport com.android.internal.util.HexDump; 435ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colittiimport com.android.internal.util.IndentingPrintWriter; 44578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 45578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.io.FileDescriptor; 46578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.io.IOException; 47578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.lang.Thread; 487d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichiimport java.net.Inet4Address; 495ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colittiimport java.net.Inet6Address; 505ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colittiimport java.net.InetAddress; 51578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.net.NetworkInterface; 52578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.net.SocketException; 535ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colittiimport java.net.UnknownHostException; 54578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.nio.ByteBuffer; 555ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colittiimport java.nio.BufferUnderflowException; 56578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.util.ArrayList; 57578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport java.util.Arrays; 58578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 59578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenimport libcore.io.IoBridge; 60578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 61578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen/** 62578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * For networks that support packet filtering via APF programs, {@code ApfFilter} 63578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * listens for IPv6 ICMPv6 router advertisements (RAs) and generates APF programs to 64578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * filter out redundant duplicate ones. 65578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * 66dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * Threading model: 67dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * A collection of RAs we've received is kept in mRas. Generating APF programs uses mRas to 68dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * know what RAs to filter for, thus generating APF programs is dependent on mRas. 69dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * mRas can be accessed by multiple threads: 70dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - ReceiveThread, which listens for RAs and adds them to mRas, and generates APF programs. 71dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - callers of: 72dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - setMulticastFilter(), which can cause an APF program to be generated. 73dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - dump(), which dumps mRas among other things. 74dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - shutdown(), which clears mRas. 75dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * So access to mRas is synchronized. 76dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * 77578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * @hide 78578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen */ 79578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensenpublic class ApfFilter { 80647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi 81647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi // Enums describing the outcome of receiving an RA packet. 82647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private static enum ProcessRaResult { 83647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi MATCH, // Received RA matched a known RA 84647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi DROPPED, // Received RA ignored due to MAX_RAS 85647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi PARSE_ERROR, // Received RA could not be parsed 86647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi ZERO_LIFETIME, // Received RA had 0 lifetime 87647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi UPDATE_NEW_RA, // APF program updated for new RA 88647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi UPDATE_EXPIRY // APF program updated for expiry 89647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 90647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi 91578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Thread to listen for RAs. 929132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen @VisibleForTesting 939132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen class ReceiveThread extends Thread { 94578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private final byte[] mPacket = new byte[1514]; 95578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private final FileDescriptor mSocket; 96578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private volatile boolean mStopped; 97578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 98647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi // Starting time of the RA receiver thread. 99647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private final long mStart = SystemClock.elapsedRealtime(); 100647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi 101647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private int mReceivedRas; // Number of received RAs 102647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private int mMatchingRas; // Number of received RAs matching a known RA 103647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private int mDroppedRas; // Number of received RAs ignored due to the MAX_RAS limit 104647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private int mParseErrors; // Number of received RAs that could not be parsed 105647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private int mZeroLifetimeRas; // Number of received RAs with a 0 lifetime 106647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private int mProgramUpdates; // Number of APF program updates triggered by receiving a RA 107647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi 108578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen public ReceiveThread(FileDescriptor socket) { 109578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mSocket = socket; 110578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 111578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 112578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen public void halt() { 113578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mStopped = true; 114578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen try { 115578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Interrupts the read() call the thread is blocked in. 116578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen IoBridge.closeAndSignalBlockedThreads(mSocket); 117578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } catch (IOException ignored) {} 118578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 119578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 120578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen @Override 121578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen public void run() { 122578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen log("begin monitoring"); 123578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen while (!mStopped) { 124578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen try { 125578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen int length = Os.read(mSocket, mPacket, 0, mPacket.length); 126647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi updateStats(processRa(mPacket, length)); 127578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } catch (IOException|ErrnoException e) { 128578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen if (!mStopped) { 129578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen Log.e(TAG, "Read error", e); 130578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 131578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 132578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 133647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi logStats(); 134647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 135647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi 136647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private void updateStats(ProcessRaResult result) { 137647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mReceivedRas++; 138647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi switch(result) { 139647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi case MATCH: 140647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mMatchingRas++; 141647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return; 142647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi case DROPPED: 143647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mDroppedRas++; 144647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return; 145647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi case PARSE_ERROR: 146647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mParseErrors++; 147647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return; 148647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi case ZERO_LIFETIME: 149647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mZeroLifetimeRas++; 150647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return; 151647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi case UPDATE_EXPIRY: 152647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mMatchingRas++; 153647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mProgramUpdates++; 154647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return; 155647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi case UPDATE_NEW_RA: 156647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mProgramUpdates++; 157647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return; 158647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 159647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 160647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi 161647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private void logStats() { 162647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi long durationMs = SystemClock.elapsedRealtime() - mStart; 163647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi int maxSize = mApfCapabilities.maximumApfProgramSize; 164647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mMetricsLog.log(new ApfStats(durationMs, mReceivedRas, mMatchingRas, mDroppedRas, 165647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi mZeroLifetimeRas, mParseErrors, mProgramUpdates, maxSize)); 166578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 167578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 168578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 169578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final String TAG = "ApfFilter"; 17039c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti private static final boolean DBG = true; 1717a8797f6c8406bbc335f67b85ef0cf00dc3a2b24Joe Onorato private static final boolean VDBG = false; 172578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 173dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int ETH_HEADER_LEN = 14; 17491723d7f7ecc07e9bfa84c445213acf1dec0664fPaul Jensen private static final int ETH_DEST_ADDR_OFFSET = 0; 175dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int ETH_ETHERTYPE_OFFSET = 12; 176961ca49fd67b39d8076ea49d12d2fda73f581399Hugo Benichi private static final byte[] ETH_BROADCAST_MAC_ADDRESS = 177961ca49fd67b39d8076ea49d12d2fda73f581399Hugo Benichi {(byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff }; 178dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // TODO: Make these offsets relative to end of link-layer header; don't include ETH_HEADER_LEN. 179dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV4_FRAGMENT_OFFSET_OFFSET = ETH_HEADER_LEN + 6; 180dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Endianness is not an issue for this constant because the APF interpreter always operates in 181dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // network byte order. 182dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV4_FRAGMENT_OFFSET_MASK = 0x1fff; 183dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV4_PROTOCOL_OFFSET = ETH_HEADER_LEN + 9; 184dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV4_DEST_ADDR_OFFSET = ETH_HEADER_LEN + 16; 18538db976514ff2ad12d207a927219762eab179882Hugo Benichi private static final int IPV4_ANY_HOST_ADDRESS = 0; 1860dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi private static final int IPV4_BROADCAST_ADDRESS = -1; // 255.255.255.255 187dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 188dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV6_NEXT_HEADER_OFFSET = ETH_HEADER_LEN + 6; 189dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV6_SRC_ADDR_OFFSET = ETH_HEADER_LEN + 8; 190dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV6_DEST_ADDR_OFFSET = ETH_HEADER_LEN + 24; 191dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int IPV6_HEADER_LEN = 40; 192dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // The IPv6 all nodes address ff02::1 193dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final byte[] IPV6_ALL_NODES_ADDRESS = 194961ca49fd67b39d8076ea49d12d2fda73f581399Hugo Benichi { (byte) 0xff, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }; 195dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 196dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int ICMP6_TYPE_OFFSET = ETH_HEADER_LEN + IPV6_HEADER_LEN; 197dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int ICMP6_NEIGHBOR_ANNOUNCEMENT = 136; 1984b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen private static final int ICMP6_ROUTER_ADVERTISEMENT = 134; 199dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 200dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // NOTE: this must be added to the IPv4 header length in IPV4_HEADER_SIZE_MEMORY_SLOT 201dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int UDP_DESTINATION_PORT_OFFSET = ETH_HEADER_LEN + 2; 202dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int UDP_HEADER_LEN = 8; 203dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 204dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int DHCP_CLIENT_PORT = 68; 205dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // NOTE: this must be added to the IPv4 header length in IPV4_HEADER_SIZE_MEMORY_SLOT 206dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private static final int DHCP_CLIENT_MAC_OFFSET = ETH_HEADER_LEN + UDP_HEADER_LEN + 28; 207dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 2084fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi private static final int ARP_HEADER_OFFSET = ETH_HEADER_LEN; 20938db976514ff2ad12d207a927219762eab179882Hugo Benichi private static final int ARP_OPCODE_OFFSET = ARP_HEADER_OFFSET + 6; 21038db976514ff2ad12d207a927219762eab179882Hugo Benichi private static final short ARP_OPCODE_REQUEST = 1; 21138db976514ff2ad12d207a927219762eab179882Hugo Benichi private static final short ARP_OPCODE_REPLY = 2; 212961ca49fd67b39d8076ea49d12d2fda73f581399Hugo Benichi private static final byte[] ARP_IPV4_HEADER = { 213a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 0, 1, // Hardware type: Ethernet (1) 214a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 8, 0, // Protocol type: IP (0x0800) 215a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 6, // Hardware size: 6 216a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 4, // Protocol size: 4 217a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen }; 2184fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi private static final int ARP_TARGET_IP_ADDRESS_OFFSET = ETH_HEADER_LEN + 24; 219a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 220f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen private final ApfCapabilities mApfCapabilities; 221f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen private final IpManager.Callback mIpManagerCallback; 222f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen private final NetworkInterface mNetworkInterface; 2236ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi private final IpConnectivityLog mMetricsLog; 2249132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen @VisibleForTesting 2259132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen byte[] mHardwareAddress; 2269132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen @VisibleForTesting 2279132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen ReceiveThread mReceiveThread; 228dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 229578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private long mUniqueCounter; 230dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 231dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private boolean mMulticastFilter; 232a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // Our IPv4 address, if we have just one, otherwise null. 233a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen @GuardedBy("this") 234a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen private byte[] mIPv4Address; 2357d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi // The subnet prefix length of our IPv4 network. Only valid if mIPv4Address is not null. 2367d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi @GuardedBy("this") 2377d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private int mIPv4PrefixLength; 238578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 2399132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen @VisibleForTesting 2409132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen ApfFilter(ApfCapabilities apfCapabilities, NetworkInterface networkInterface, 2416ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi IpManager.Callback ipManagerCallback, boolean multicastFilter, IpConnectivityLog log) { 242f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen mApfCapabilities = apfCapabilities; 243f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen mIpManagerCallback = ipManagerCallback; 244f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen mNetworkInterface = networkInterface; 2452e074db972355a77f91378b5b1daceb500dde019Paul Jensen mMulticastFilter = multicastFilter; 2466ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi mMetricsLog = log; 247f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen 248578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen maybeStartFilter(); 249578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 250578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 251578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private void log(String s) { 252f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen Log.d(TAG, "(" + mNetworkInterface.getName() + "): " + s); 253578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 254578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 255dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 256dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private long getUniqueNumberLocked() { 257578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return mUniqueCounter++; 258578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 259578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 260578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen /** 261578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * Attempt to start listening for RAs and, if RAs are received, generating and installing 262578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * filters to ignore useless RAs. 263578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen */ 2649132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen @VisibleForTesting 2659132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen void maybeStartFilter() { 266578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen FileDescriptor socket; 267578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen try { 268f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen mHardwareAddress = mNetworkInterface.getHardwareAddress(); 269dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen synchronized(this) { 270dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Install basic filters 271dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen installNewProgramLocked(); 272dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 273578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen socket = Os.socket(AF_PACKET, SOCK_RAW, ETH_P_IPV6); 274578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen PacketSocketAddress addr = new PacketSocketAddress((short) ETH_P_IPV6, 275f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen mNetworkInterface.getIndex()); 276578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen Os.bind(socket, addr); 277f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen NetworkUtils.attachRaFilter(socket, mApfCapabilities.apfPacketFormat); 278578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } catch(SocketException|ErrnoException e) { 279dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen Log.e(TAG, "Error starting filter", e); 280578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return; 281578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 282578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mReceiveThread = new ReceiveThread(socket); 283578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mReceiveThread.start(); 284578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 285578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 286578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Returns seconds since Unix Epoch. 287647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi // TODO: use SystemClock.elapsedRealtime() instead 288578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static long curTime() { 2894fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi return System.currentTimeMillis() / DateUtils.SECOND_IN_MILLIS; 290578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 291578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 2920668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi public static class InvalidRaException extends Exception { 2930668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi public InvalidRaException(String m) { 2940668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi super(m); 2950668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi } 2960668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi } 2970668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi 298578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // A class to hold information about an RA. 2990668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi @VisibleForTesting 3000668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi class Ra { 301578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // From RFC4861: 302578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_RA_HEADER_LEN = 16; 303e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti private static final int ICMP6_RA_CHECKSUM_OFFSET = 304e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti ETH_HEADER_LEN + IPV6_HEADER_LEN + 2; 305e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti private static final int ICMP6_RA_CHECKSUM_LEN = 2; 306578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_RA_OPTION_OFFSET = 307578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ETH_HEADER_LEN + IPV6_HEADER_LEN + ICMP6_RA_HEADER_LEN; 308578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_RA_ROUTER_LIFETIME_OFFSET = 309578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ETH_HEADER_LEN + IPV6_HEADER_LEN + 6; 310578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_RA_ROUTER_LIFETIME_LEN = 2; 311578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Prefix information option. 312578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_PREFIX_OPTION_TYPE = 3; 313578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_PREFIX_OPTION_LEN = 32; 314578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_PREFIX_OPTION_VALID_LIFETIME_OFFSET = 4; 315578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_PREFIX_OPTION_VALID_LIFETIME_LEN = 4; 316578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_OFFSET = 8; 317578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_LEN = 4; 318578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 319578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // From RFC6106: Recursive DNS Server option 320578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_RDNSS_OPTION_TYPE = 25; 321578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // From RFC6106: DNS Search List option 322578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_DNSSL_OPTION_TYPE = 31; 323578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 324578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // From RFC4191: Route Information option 325578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_ROUTE_INFO_OPTION_TYPE = 24; 326578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Above three options all have the same format: 327578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_4_BYTE_LIFETIME_OFFSET = 4; 328578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int ICMP6_4_BYTE_LIFETIME_LEN = 4; 329578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 3301c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen // Note: mPacket's position() cannot be assumed to be reset. 331578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private final ByteBuffer mPacket; 332578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // List of binary ranges that include the whole packet except the lifetimes. 333578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Pairs consist of offset and length. 334578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private final ArrayList<Pair<Integer, Integer>> mNonLifetimes = 335578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen new ArrayList<Pair<Integer, Integer>>(); 336578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Minimum lifetime in packet 337578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long mMinLifetime; 338578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // When the packet was last captured, in seconds since Unix Epoch 339578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long mLastSeen; 340578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 3415ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // For debugging only. Offsets into the packet where PIOs are. 342059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti private final ArrayList<Integer> mPrefixOptionOffsets = new ArrayList<>(); 343059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 344059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti // For debugging only. Offsets into the packet where RDNSS options are. 345059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti private final ArrayList<Integer> mRdnssOptionOffsets = new ArrayList<>(); 346059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 3475ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // For debugging only. How many times this RA was seen. 3485ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti int seenCount = 0; 3495ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 35039c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti // For debugging only. Returns the hex representation of the last matching packet. 35139c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti String getLastMatchingPacket() { 352059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti return HexDump.toHexString(mPacket.array(), 0, mPacket.capacity(), 353059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti false /* lowercase */); 35439c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti } 3555ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 356059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti // For debugging only. Returns the string representation of the IPv6 address starting at 357059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti // position pos in the packet. 3585ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti private String IPv6AddresstoString(int pos) { 3595ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti try { 3605ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti byte[] array = mPacket.array(); 3615ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // Can't just call copyOfRange() and see if it throws, because if it reads past the 3625ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // end it pads with zeros instead of throwing. 3635ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti if (pos < 0 || pos + 16 > array.length || pos + 16 < pos) { 3645ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return "???"; 3655ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 3665ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti byte[] addressBytes = Arrays.copyOfRange(array, pos, pos + 16); 3675ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti InetAddress address = (Inet6Address) InetAddress.getByAddress(addressBytes); 3685ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return address.getHostAddress(); 3695ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } catch (UnsupportedOperationException e) { 3705ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // array() failed. Cannot happen, mPacket is array-backed and read-write. 3715ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return "???"; 3720668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi } catch (ClassCastException|UnknownHostException e) { 3735ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // Cannot happen. 3745ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return "???"; 3755ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 3765ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 3775ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 3785ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti // Can't be static because it's in a non-static inner class. 379cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi // TODO: Make this static once RA is its own class. 380059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti private void prefixOptionToString(StringBuffer sb, int offset) { 381059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti String prefix = IPv6AddresstoString(offset + 16); 382059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti int length = uint8(mPacket.get(offset + 2)); 383059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti long valid = mPacket.getInt(offset + 4); 384059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti long preferred = mPacket.getInt(offset + 8); 385059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti sb.append(String.format("%s/%d %ds/%ds ", prefix, length, valid, preferred)); 386059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti } 387059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 388059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti private void rdnssOptionToString(StringBuffer sb, int offset) { 389059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti int optLen = uint8(mPacket.get(offset + 1)) * 8; 390059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti if (optLen < 24) return; // Malformed or empty. 391059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti long lifetime = uint32(mPacket.getInt(offset + 4)); 392059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti int numServers = (optLen - 8) / 16; 393059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti sb.append("DNS ").append(lifetime).append("s"); 394059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti for (int server = 0; server < numServers; server++) { 395059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti sb.append(" ").append(IPv6AddresstoString(offset + 8 + 16 * server)); 396059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti } 397059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti } 398059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 3995ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti public String toString() { 4005ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti try { 4015ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti StringBuffer sb = new StringBuffer(); 402059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti sb.append(String.format("RA %s -> %s %ds ", 4035ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti IPv6AddresstoString(IPV6_SRC_ADDR_OFFSET), 404dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen IPv6AddresstoString(IPV6_DEST_ADDR_OFFSET), 4055ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti uint16(mPacket.getShort(ICMP6_RA_ROUTER_LIFETIME_OFFSET)))); 4065ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti for (int i: mPrefixOptionOffsets) { 407059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti prefixOptionToString(sb, i); 408059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti } 409059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti for (int i: mRdnssOptionOffsets) { 410059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti rdnssOptionToString(sb, i); 4115ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 4125ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return sb.toString(); 4130668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi } catch (BufferUnderflowException|IndexOutOfBoundsException e) { 4145ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return "<Malformed RA>"; 4155ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 4165ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 4175ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 418578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen /** 419578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * Add a binary range of the packet that does not include a lifetime to mNonLifetimes. 420578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * Assumes mPacket.position() is as far as we've parsed the packet. 421578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * @param lastNonLifetimeStart offset within packet of where the last binary range of 422578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * data not including a lifetime. 423578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * @param lifetimeOffset offset from mPacket.position() to the next lifetime data. 424578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * @param lifetimeLength length of the next lifetime data. 425578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * @return offset within packet of where the next binary range of data not including 4266ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi * a lifetime. This can be passed into the next invocation of this function 427578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * via {@code lastNonLifetimeStart}. 428578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen */ 429578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private int addNonLifetime(int lastNonLifetimeStart, int lifetimeOffset, 430578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen int lifetimeLength) { 431578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen lifetimeOffset += mPacket.position(); 432578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mNonLifetimes.add(new Pair<Integer, Integer>(lastNonLifetimeStart, 433578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen lifetimeOffset - lastNonLifetimeStart)); 434578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return lifetimeOffset + lifetimeLength; 435578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 436578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 437cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi private int addNonLifetimeU32(int lastNonLifetimeStart) { 438cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi return addNonLifetime(lastNonLifetimeStart, 439cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi ICMP6_4_BYTE_LIFETIME_OFFSET, ICMP6_4_BYTE_LIFETIME_LEN); 440cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi } 441cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi 442578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Note that this parses RA and may throw IllegalArgumentException (from 4438995d85b9432387520c9f04a69251536754b996bLorenzo Colitti // Buffer.position(int) or due to an invalid-length option) or IndexOutOfBoundsException 4448995d85b9432387520c9f04a69251536754b996bLorenzo Colitti // (from ByteBuffer.get(int) ) if parsing encounters something non-compliant with 4458995d85b9432387520c9f04a69251536754b996bLorenzo Colitti // specifications. 4460668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi Ra(byte[] packet, int length) throws InvalidRaException { 4470668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi if (length < ICMP6_RA_OPTION_OFFSET) { 4480668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi throw new InvalidRaException("Not an ICMP6 router advertisement"); 4490668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi } 4500668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi 4516ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi mPacket = ByteBuffer.wrap(Arrays.copyOf(packet, length)); 452578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mLastSeen = curTime(); 4534b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen 4544b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen // Sanity check packet in case a packet arrives before we attach RA filter 4554b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen // to our packet socket. b/29586253 4564b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen if (getUint16(mPacket, ETH_ETHERTYPE_OFFSET) != ETH_P_IPV6 || 4574b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen uint8(mPacket.get(IPV6_NEXT_HEADER_OFFSET)) != IPPROTO_ICMPV6 || 4584b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen uint8(mPacket.get(ICMP6_TYPE_OFFSET)) != ICMP6_ROUTER_ADVERTISEMENT) { 4590668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi throw new InvalidRaException("Not an ICMP6 router advertisement"); 4604b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen } 4614b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen 4624b545b04f6533b5e0377f2d2dec219ad816e47edPaul Jensen 4636ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi RaEvent.Builder builder = new RaEvent.Builder(); 464578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 465e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti // Ignore the checksum. 466e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti int lastNonLifetimeStart = addNonLifetime(0, 467e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti ICMP6_RA_CHECKSUM_OFFSET, 468e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti ICMP6_RA_CHECKSUM_LEN); 469e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti 470578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Parse router lifetime 471e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart, 472e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti ICMP6_RA_ROUTER_LIFETIME_OFFSET, 473578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ICMP6_RA_ROUTER_LIFETIME_LEN); 4746ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi builder.updateRouterLifetime(getUint16(mPacket, ICMP6_RA_ROUTER_LIFETIME_OFFSET)); 475cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi 476059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti // Ensures that the RA is not truncated. 477578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mPacket.position(ICMP6_RA_OPTION_OFFSET); 478578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen while (mPacket.hasRemaining()) { 479cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi final int position = mPacket.position(); 480cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi final int optionType = uint8(mPacket.get(position)); 481cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi final int optionLength = uint8(mPacket.get(position + 1)) * 8; 4826ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi long lifetime; 483578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen switch (optionType) { 484578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen case ICMP6_PREFIX_OPTION_TYPE: 485578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Parse valid lifetime 486578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart, 487578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ICMP6_PREFIX_OPTION_VALID_LIFETIME_OFFSET, 488578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ICMP6_PREFIX_OPTION_VALID_LIFETIME_LEN); 4896ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi lifetime = getUint32(mPacket, 4906ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi position + ICMP6_PREFIX_OPTION_VALID_LIFETIME_OFFSET); 4916ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi builder.updatePrefixValidLifetime(lifetime); 492578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Parse preferred lifetime 493578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart, 494578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_OFFSET, 495578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_LEN); 4966ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi lifetime = getUint32(mPacket, 4976ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi position + ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_OFFSET); 4986ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi builder.updatePrefixPreferredLifetime(lifetime); 499cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi mPrefixOptionOffsets.add(position); 500578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen break; 501cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi // These three options have the same lifetime offset and size, and 5026ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi // are processed with the same specialized addNonLifetimeU32: 503578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen case ICMP6_RDNSS_OPTION_TYPE: 504cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi mRdnssOptionOffsets.add(position); 505cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi lastNonLifetimeStart = addNonLifetimeU32(lastNonLifetimeStart); 5066ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi lifetime = getUint32(mPacket, position + ICMP6_4_BYTE_LIFETIME_OFFSET); 5076ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi builder.updateRdnssLifetime(lifetime); 508cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi break; 509059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti case ICMP6_ROUTE_INFO_OPTION_TYPE: 510cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi lastNonLifetimeStart = addNonLifetimeU32(lastNonLifetimeStart); 5116ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi lifetime = getUint32(mPacket, position + ICMP6_4_BYTE_LIFETIME_OFFSET); 5126ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi builder.updateRouteInfoLifetime(lifetime); 513cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi break; 514578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen case ICMP6_DNSSL_OPTION_TYPE: 515cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi lastNonLifetimeStart = addNonLifetimeU32(lastNonLifetimeStart); 5166ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi lifetime = getUint32(mPacket, position + ICMP6_4_BYTE_LIFETIME_OFFSET); 5176ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi builder.updateDnsslLifetime(lifetime); 518578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen break; 519578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen default: 520578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // RFC4861 section 4.2 dictates we ignore unknown options for fowards 521578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // compatibility. 522578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen break; 523578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 5248995d85b9432387520c9f04a69251536754b996bLorenzo Colitti if (optionLength <= 0) { 5250668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi throw new InvalidRaException(String.format( 5268995d85b9432387520c9f04a69251536754b996bLorenzo Colitti "Invalid option length opt=%d len=%d", optionType, optionLength)); 5278995d85b9432387520c9f04a69251536754b996bLorenzo Colitti } 528cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi mPacket.position(position + optionLength); 529578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 530578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Mark non-lifetime bytes since last lifetime. 531578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen addNonLifetime(lastNonLifetimeStart, 0, 0); 532578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mMinLifetime = minLifetime(packet, length); 5336ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi mMetricsLog.log(builder.build()); 534578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 535578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 536578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Ignoring lifetimes (which may change) does {@code packet} match this RA? 537578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen boolean matches(byte[] packet, int length) { 5381c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen if (length != mPacket.capacity()) return false; 5391c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen byte[] referencePacket = mPacket.array(); 540578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen for (Pair<Integer, Integer> nonLifetime : mNonLifetimes) { 5411c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen for (int i = nonLifetime.first; i < (nonLifetime.first + nonLifetime.second); i++) { 5421c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen if (packet[i] != referencePacket[i]) return false; 5431c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen } 544578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 545578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return true; 546578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 547578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 548578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // What is the minimum of all lifetimes within {@code packet} in seconds? 549578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Precondition: matches(packet, length) already returned true. 550578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long minLifetime(byte[] packet, int length) { 551578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long minLifetime = Long.MAX_VALUE; 552578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Wrap packet in ByteBuffer so we can read big-endian values easily 553578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ByteBuffer byteBuffer = ByteBuffer.wrap(packet); 554578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen for (int i = 0; (i + 1) < mNonLifetimes.size(); i++) { 555578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen int offset = mNonLifetimes.get(i).first + mNonLifetimes.get(i).second; 556e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti 557e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti // The checksum is in mNonLifetimes, but it's not a lifetime. 558e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti if (offset == ICMP6_RA_CHECKSUM_OFFSET) { 559e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti continue; 560e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti } 561e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti 562cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi final int lifetimeLength = mNonLifetimes.get(i+1).first - offset; 563cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi final long optionLifetime; 564578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen switch (lifetimeLength) { 565cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi case 2: 566cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi optionLifetime = uint16(byteBuffer.getShort(offset)); 567cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi break; 568cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi case 4: 569cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi optionLifetime = uint32(byteBuffer.getInt(offset)); 570cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi break; 571cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi default: 572cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi throw new IllegalStateException("bogus lifetime size " + lifetimeLength); 573578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 574cfbf7414a14cf91d1b5c83154aab54c32d6be76aHugo Benichi minLifetime = Math.min(minLifetime, optionLifetime); 575578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 576578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return minLifetime; 577578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 578578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 579578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // How many seconds does this RA's have to live, taking into account the fact 580578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // that we might have seen it a while ago. 581578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long currentLifetime() { 582578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return mMinLifetime - (curTime() - mLastSeen); 583578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 584578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 585578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen boolean isExpired() { 586dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // TODO: We may want to handle 0 lifetime RAs differently, if they are common. We'll 587dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // have to calculte the filter lifetime specially as a fraction of 0 is still 0. 588dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen return currentLifetime() <= 0; 589578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 590578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 591578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Append a filter for this RA to {@code gen}. Jump to DROP_LABEL if it should be dropped. 592578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Jump to the next filter if packet doesn't match this RA. 593dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("ApfFilter.this") 594dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen long generateFilterLocked(ApfGenerator gen) throws IllegalInstructionException { 595dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen String nextFilterLabel = "Ra" + getUniqueNumberLocked(); 596578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Skip if packet is not the right size 597578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen gen.addLoadFromMemory(Register.R0, gen.PACKET_SIZE_MEMORY_SLOT); 5981c71cb3e728c5f7b3bc76daf581e108ed5c0fa3cPaul Jensen gen.addJumpIfR0NotEquals(mPacket.capacity(), nextFilterLabel); 599578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen int filterLifetime = (int)(currentLifetime() / FRACTION_OF_LIFETIME_TO_FILTER); 600578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Skip filter if expired 601578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen gen.addLoadFromMemory(Register.R0, gen.FILTER_AGE_MEMORY_SLOT); 602578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen gen.addJumpIfR0GreaterThan(filterLifetime, nextFilterLabel); 603578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen for (int i = 0; i < mNonLifetimes.size(); i++) { 604578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Generate code to match the packet bytes 605578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen Pair<Integer, Integer> nonLifetime = mNonLifetimes.get(i); 6067c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen // Don't generate JNEBS instruction for 0 bytes as it always fails the 6077c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen // ASSERT_FORWARD_IN_PROGRAM(pc + cmp_imm - 1) check where cmp_imm is 6087c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen // the number of bytes to compare. nonLifetime is zero between the 6097c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen // valid and preferred lifetimes in the prefix option. 6107c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen if (nonLifetime.second != 0) { 6117c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen gen.addLoadImmediate(Register.R0, nonLifetime.first); 6127c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen gen.addJumpIfBytesNotEqual(Register.R0, 6137c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen Arrays.copyOfRange(mPacket.array(), nonLifetime.first, 6147c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen nonLifetime.first + nonLifetime.second), 6157c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen nextFilterLabel); 6167c34b15f749fdc4889cf2ee77edab9f017281c65Paul Jensen } 617578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Generate code to test the lifetimes haven't gone down too far 618578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen if ((i + 1) < mNonLifetimes.size()) { 619578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen Pair<Integer, Integer> nextNonLifetime = mNonLifetimes.get(i + 1); 620578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen int offset = nonLifetime.first + nonLifetime.second; 621e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti // Skip the checksum. 622e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti if (offset == ICMP6_RA_CHECKSUM_OFFSET) { 623e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti continue; 624e6dfc1736b3e37ad2ea0e9005cab36432de196b2Lorenzo Colitti } 625578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen int length = nextNonLifetime.first - offset; 626578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen switch (length) { 627578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen case 4: gen.addLoad32(Register.R0, offset); break; 628578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen case 2: gen.addLoad16(Register.R0, offset); break; 629578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen default: throw new IllegalStateException("bogus lifetime size " + length); 630578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 631578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen gen.addJumpIfR0LessThan(filterLifetime, nextFilterLabel); 632578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 633578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 634578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen gen.addJump(gen.DROP_LABEL); 635578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen gen.defineLabel(nextFilterLabel); 636578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return filterLifetime; 637578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 638578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 639578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 640578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Maximum number of RAs to filter for. 641578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int MAX_RAS = 10; 642dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 643dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 644578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private ArrayList<Ra> mRas = new ArrayList<Ra>(); 645578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 646578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // There is always some marginal benefit to updating the installed APF program when an RA is 647578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // seen because we can extend the program's lifetime slightly, but there is some cost to 648578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // updating the program, so don't bother unless the program is going to expire soon. This 649578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // constant defines "soon" in seconds. 650578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final long MAX_PROGRAM_LIFETIME_WORTH_REFRESHING = 30; 651578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // We don't want to filter an RA for it's whole lifetime as it'll be expired by the time we ever 652578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // see a refresh. Using half the lifetime might be a good idea except for the fact that 653578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // packets may be dropped, so let's use 6. 654578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private static final int FRACTION_OF_LIFETIME_TO_FILTER = 6; 655578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 656578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // When did we last install a filter program? In seconds since Unix Epoch. 657dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 658578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private long mLastTimeInstalledProgram; 659578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // How long should the last installed filter program live for? In seconds. 660dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 661578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private long mLastInstalledProgramMinLifetime; 662578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 663dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // For debugging only. The last program installed. 664dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 66539c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti private byte[] mLastInstalledProgram; 6665ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 667059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti // For debugging only. How many times the program was updated since we started. 668059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti @GuardedBy("this") 669059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti private int mNumProgramUpdates; 670059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 671dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen /** 672a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen * Generate filter code to process ARP packets. Execution of this code ends in either the 673a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen * DROP_LABEL or PASS_LABEL and does not fall off the end. 674a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen * Preconditions: 675a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen * - Packet being filtered is ARP 676a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen */ 677a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen @GuardedBy("this") 678a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen private void generateArpFilterLocked(ApfGenerator gen) throws IllegalInstructionException { 679a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // Here's a basic summary of what the ARP filter program does: 680a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // 68138db976514ff2ad12d207a927219762eab179882Hugo Benichi // if not ARP IPv4 68238db976514ff2ad12d207a927219762eab179882Hugo Benichi // pass 68338db976514ff2ad12d207a927219762eab179882Hugo Benichi // if not ARP IPv4 reply or request 68438db976514ff2ad12d207a927219762eab179882Hugo Benichi // pass 68538db976514ff2ad12d207a927219762eab179882Hugo Benichi // if unicast ARP reply 68638db976514ff2ad12d207a927219762eab179882Hugo Benichi // pass 68738db976514ff2ad12d207a927219762eab179882Hugo Benichi // if interface has no IPv4 address 68838db976514ff2ad12d207a927219762eab179882Hugo Benichi // if target ip is 0.0.0.0 68938db976514ff2ad12d207a927219762eab179882Hugo Benichi // drop 69038db976514ff2ad12d207a927219762eab179882Hugo Benichi // else 69138db976514ff2ad12d207a927219762eab179882Hugo Benichi // if target ip is not the interface ip 69238db976514ff2ad12d207a927219762eab179882Hugo Benichi // drop 693a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // pass 694a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 69538db976514ff2ad12d207a927219762eab179882Hugo Benichi final String checkTargetIPv4 = "checkTargetIPv4"; 69638db976514ff2ad12d207a927219762eab179882Hugo Benichi 69738db976514ff2ad12d207a927219762eab179882Hugo Benichi // Pass if not ARP IPv4. 69838db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addLoadImmediate(Register.R0, ARP_HEADER_OFFSET); 69938db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addJumpIfBytesNotEqual(Register.R0, ARP_IPV4_HEADER, gen.PASS_LABEL); 70038db976514ff2ad12d207a927219762eab179882Hugo Benichi 70138db976514ff2ad12d207a927219762eab179882Hugo Benichi // Pass if unknown ARP opcode. 70238db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addLoad16(Register.R0, ARP_OPCODE_OFFSET); 70338db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addJumpIfR0Equals(ARP_OPCODE_REQUEST, checkTargetIPv4); // Skip to unicast check 70438db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addJumpIfR0NotEquals(ARP_OPCODE_REPLY, gen.PASS_LABEL); 70538db976514ff2ad12d207a927219762eab179882Hugo Benichi 70638db976514ff2ad12d207a927219762eab179882Hugo Benichi // Pass if unicast reply. 70738db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addLoadImmediate(Register.R0, ETH_DEST_ADDR_OFFSET); 70838db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addJumpIfBytesNotEqual(Register.R0, ETH_BROADCAST_MAC_ADDRESS, gen.PASS_LABEL); 70938db976514ff2ad12d207a927219762eab179882Hugo Benichi 71038db976514ff2ad12d207a927219762eab179882Hugo Benichi // Either a unicast request, a unicast reply, or a broadcast reply. 71138db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.defineLabel(checkTargetIPv4); 71238db976514ff2ad12d207a927219762eab179882Hugo Benichi if (mIPv4Address == null) { 71338db976514ff2ad12d207a927219762eab179882Hugo Benichi // When there is no IPv4 address, drop GARP replies (b/29404209). 71438db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addLoad32(Register.R0, ARP_TARGET_IP_ADDRESS_OFFSET); 71538db976514ff2ad12d207a927219762eab179882Hugo Benichi gen.addJumpIfR0Equals(IPV4_ANY_HOST_ADDRESS, gen.DROP_LABEL); 71638db976514ff2ad12d207a927219762eab179882Hugo Benichi } else { 71738db976514ff2ad12d207a927219762eab179882Hugo Benichi // When there is an IPv4 address, drop unicast/broadcast requests 71838db976514ff2ad12d207a927219762eab179882Hugo Benichi // and broadcast replies with a different target IPv4 address. 719dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addLoadImmediate(Register.R0, ARP_TARGET_IP_ADDRESS_OFFSET); 720dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addJumpIfBytesNotEqual(Register.R0, mIPv4Address, gen.DROP_LABEL); 721dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen } 722a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 723a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen gen.addJump(gen.PASS_LABEL); 724a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen } 725a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 726a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen /** 727dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * Generate filter code to process IPv4 packets. Execution of this code ends in either the 728dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * DROP_LABEL or PASS_LABEL and does not fall off the end. 729dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * Preconditions: 730dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - Packet being filtered is IPv4 731dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen */ 732dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 733dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private void generateIPv4FilterLocked(ApfGenerator gen) throws IllegalInstructionException { 734dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Here's a basic summary of what the IPv4 filter program does: 735dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // 736f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen // if filtering multicast (i.e. multicast lock not held): 7370dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // if it's DHCP destined to our MAC: 738f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen // pass 7390dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // if it's L2 broadcast: 7400dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // drop 7410dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // if it's IPv4 multicast: 7420dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // drop 7430dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // if it's IPv4 broadcast: 744f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen // drop 745dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // pass 746dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 747dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen if (mMulticastFilter) { 7480dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi final String skipDhcpv4Filter = "skip_dhcp_v4_filter"; 749dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 7500dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // Pass DHCP addressed to us. 7510dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // Check it's UDP. 752f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen gen.addLoad8(Register.R0, IPV4_PROTOCOL_OFFSET); 7530dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfR0NotEquals(IPPROTO_UDP, skipDhcpv4Filter); 7540dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // Check it's not a fragment. This matches the BPF filter installed by the DHCP client. 755f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen gen.addLoad16(Register.R0, IPV4_FRAGMENT_OFFSET_OFFSET); 7560dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfR0AnyBitsSet(IPV4_FRAGMENT_OFFSET_MASK, skipDhcpv4Filter); 7570dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // Check it's addressed to DHCP client port. 758f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen gen.addLoadFromMemory(Register.R1, gen.IPV4_HEADER_SIZE_MEMORY_SLOT); 759f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen gen.addLoad16Indexed(Register.R0, UDP_DESTINATION_PORT_OFFSET); 7600dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfR0NotEquals(DHCP_CLIENT_PORT, skipDhcpv4Filter); 7610dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // Check it's DHCP to our MAC address. 762f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen gen.addLoadImmediate(Register.R0, DHCP_CLIENT_MAC_OFFSET); 763f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen // NOTE: Relies on R1 containing IPv4 header offset. 764f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen gen.addAddR1(); 7650dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfBytesNotEqual(Register.R0, mHardwareAddress, skipDhcpv4Filter); 7660dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJump(gen.PASS_LABEL); 7670dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi 7680dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // Drop all multicasts/broadcasts. 7690dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.defineLabel(skipDhcpv4Filter); 7700dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi 7710dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // If IPv4 destination address is in multicast range, drop. 7720dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addLoad8(Register.R0, IPV4_DEST_ADDR_OFFSET); 7730dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addAnd(0xf0); 7740dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfR0Equals(0xe0, gen.DROP_LABEL); 7750dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi 7760dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // If IPv4 broadcast packet, drop regardless of L2 (b/30231088). 7770dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addLoad32(Register.R0, IPV4_DEST_ADDR_OFFSET); 7780dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfR0Equals(IPV4_BROADCAST_ADDRESS, gen.DROP_LABEL); 7797d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi if (mIPv4Address != null && mIPv4PrefixLength < 31) { 7807d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi int broadcastAddr = ipv4BroadcastAddress(mIPv4Address, mIPv4PrefixLength); 7817d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi gen.addJumpIfR0Equals(broadcastAddr, gen.DROP_LABEL); 7827d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 7830dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi 7840dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi // If L2 broadcast packet, drop. 7850dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addLoadImmediate(Register.R0, ETH_DEST_ADDR_OFFSET); 7860dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJumpIfBytesNotEqual(Register.R0, ETH_BROADCAST_MAC_ADDRESS, gen.PASS_LABEL); 7870dc1d314709d579ccdc3fc59a5f66557f6cd319dHugo Benichi gen.addJump(gen.DROP_LABEL); 788f8a01e84317fcb9d27a294e95603b846143c7fcbPaul Jensen } 789dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 790dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Otherwise, pass 791dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addJump(gen.PASS_LABEL); 792dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 793dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 794dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 795dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen /** 796dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * Generate filter code to process IPv6 packets. Execution of this code ends in either the 797dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * DROP_LABEL or PASS_LABEL, or falls off the end for ICMPv6 packets. 798dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * Preconditions: 799dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * - Packet being filtered is IPv6 800dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen */ 801dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 802dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private void generateIPv6FilterLocked(ApfGenerator gen) throws IllegalInstructionException { 803dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Here's a basic summary of what the IPv6 filter program does: 804dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // 805dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // if it's not ICMPv6: 80611e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // if it's multicast and we're dropping multicast: 80711e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // drop 808dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // pass 809dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // if it's ICMPv6 NA to ff02::1: 810dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // drop 811dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 812dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addLoad8(Register.R0, IPV6_NEXT_HEADER_OFFSET); 81311e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti 81411e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // Drop multicast if the multicast filter is enabled. 81511e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti if (mMulticastFilter) { 81611e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // Don't touch ICMPv6 multicast here, we deal with it in more detail later. 81711e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti String skipIpv6MulticastFilterLabel = "skipIPv6MulticastFilter"; 81811e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti gen.addJumpIfR0Equals(IPPROTO_ICMPV6, skipIpv6MulticastFilterLabel); 81911e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti 82011e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // Drop all other packets sent to ff00::/8. 82111e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti gen.addLoad8(Register.R0, IPV6_DEST_ADDR_OFFSET); 82211e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti gen.addJumpIfR0Equals(0xff, gen.DROP_LABEL); 82311e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // Not multicast and not ICMPv6. Pass. 82411e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti gen.addJump(gen.PASS_LABEL); 82511e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti gen.defineLabel(skipIpv6MulticastFilterLabel); 82611e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti } else { 82711e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti // If not ICMPv6, pass. 82811e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti gen.addJumpIfR0NotEquals(IPPROTO_ICMPV6, gen.PASS_LABEL); 82911e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti } 83011e13e2175674389ed18c2b1e1af69c5ad931e8fLorenzo Colitti 831dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Add unsolicited multicast neighbor announcements filter 832dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen String skipUnsolicitedMulticastNALabel = "skipUnsolicitedMulticastNA"; 833dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // If not neighbor announcements, skip unsolicited multicast NA filter 834dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addLoad8(Register.R0, ICMP6_TYPE_OFFSET); 835dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addJumpIfR0NotEquals(ICMP6_NEIGHBOR_ANNOUNCEMENT, skipUnsolicitedMulticastNALabel); 836dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // If to ff02::1, drop 837dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // TODO: Drop only if they don't contain the address of on-link neighbours. 838dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addLoadImmediate(Register.R0, IPV6_DEST_ADDR_OFFSET); 839dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addJumpIfBytesNotEqual(Register.R0, IPV6_ALL_NODES_ADDRESS, 840dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen skipUnsolicitedMulticastNALabel); 841dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addJump(gen.DROP_LABEL); 842dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.defineLabel(skipUnsolicitedMulticastNALabel); 843dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 844dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 845dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen /** 846dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * Begin generating an APF program to: 847dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <ul> 848a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen * <li>Drop ARP requests not for us, if mIPv4Address is set, 849dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Drop IPv4 broadcast packets, except DHCP destined to our MAC, 850dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Drop IPv4 multicast packets, if mMulticastFilter, 851dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Pass all other IPv4 packets, 852dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen * <li>Drop all broadcast non-IP non-ARP packets. 853dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Pass all non-ICMPv6 IPv6 packets, 854dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Pass all non-IPv4 and non-IPv6 packets, 855dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Drop IPv6 ICMPv6 NAs to ff02::1. 856dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * <li>Let execution continue off the end of the program for IPv6 ICMPv6 packets. This allows 857dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * insertion of RA filters here, or if there aren't any, just passes the packets. 858dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen * </ul> 859dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen */ 860dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 861dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private ApfGenerator beginProgramLocked() throws IllegalInstructionException { 862dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen ApfGenerator gen = new ApfGenerator(); 863dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // This is guaranteed to return true because of the check in maybeCreate. 864f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen gen.setApfVersion(mApfCapabilities.apfVersionSupported); 865dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 866dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Here's a basic summary of what the initial program does: 867dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // 868a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // if it's ARP: 869dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // insert ARP filter to drop or pass these appropriately 870dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // if it's IPv4: 871dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // insert IPv4 filter to drop or pass these appropriately 872dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // if it's not IPv6: 873dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // if it's broadcast: 874dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // drop 875dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // pass 876dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // insert IPv6 filter to drop, pass, or fall off the end for ICMPv6 packets 877dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 878dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // Add ARP filters: 879dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen String skipArpFiltersLabel = "skipArpFilters"; 880a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen gen.addLoad16(Register.R0, ETH_ETHERTYPE_OFFSET); 881dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addJumpIfR0NotEquals(ETH_P_ARP, skipArpFiltersLabel); 882dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen generateArpFilterLocked(gen); 883dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.defineLabel(skipArpFiltersLabel); 884a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 885dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Add IPv4 filters: 886dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen String skipIPv4FiltersLabel = "skipIPv4Filters"; 887a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // NOTE: Relies on R0 containing ethertype. This is safe because if we got here, we did not 888a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // execute the ARP filter, since that filter does not fall through, but either drops or 889a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // passes. 890dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.addJumpIfR0NotEquals(ETH_P_IP, skipIPv4FiltersLabel); 891dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen generateIPv4FilterLocked(gen); 892dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen.defineLabel(skipIPv4FiltersLabel); 893dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 894dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // Check for IPv6: 895dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // NOTE: Relies on R0 containing ethertype. This is safe because if we got here, we did not 896a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // execute the ARP or IPv4 filters, since those filters do not fall through, but either 897a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // drop or pass. 898dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen String ipv6FilterLabel = "IPv6Filters"; 899dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addJumpIfR0Equals(ETH_P_IPV6, ipv6FilterLabel); 900dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen 901dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // Drop non-IP non-ARP broadcasts, pass the rest 902dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addLoadImmediate(Register.R0, ETH_DEST_ADDR_OFFSET); 903dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addJumpIfBytesNotEqual(Register.R0, ETH_BROADCAST_MAC_ADDRESS, gen.PASS_LABEL); 904dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.addJump(gen.DROP_LABEL); 905dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen 906dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen // Add IPv6 filters: 907dd7bee87725795d0d71c5f6a309dda78df957d8aPaul Jensen gen.defineLabel(ipv6FilterLabel); 908dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen generateIPv6FilterLocked(gen); 909dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen return gen; 910dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 911dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 9124fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi /** 9134fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi * Generate and install a new filter program. 9144fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi */ 915dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 9169132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen @VisibleForTesting 9179132f34976f16a626c2ec1d3d90624d71e054346Paul Jensen void installNewProgramLocked() { 918dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen purgeExpiredRasLocked(); 9194fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi ArrayList<Ra> rasToFilter = new ArrayList<>(); 920578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen final byte[] program; 921578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long programMinLifetime = Long.MAX_VALUE; 922578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen try { 923578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Step 1: Determine how many RA filters we can fit in the program. 924dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen ApfGenerator gen = beginProgramLocked(); 925578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen for (Ra ra : mRas) { 926dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen ra.generateFilterLocked(gen); 927dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Stop if we get too big. 928f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen if (gen.programLengthOverEstimate() > mApfCapabilities.maximumApfProgramSize) break; 929dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen rasToFilter.add(ra); 930578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 931dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Step 2: Actually generate the program 932dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen gen = beginProgramLocked(); 933dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen for (Ra ra : rasToFilter) { 934dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen programMinLifetime = Math.min(programMinLifetime, ra.generateFilterLocked(gen)); 935578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 936578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Execution will reach the end of the program if no filters match, which will pass the 937578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // packet to the AP. 938578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen program = gen.generate(); 9390668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi } catch (IllegalInstructionException|IllegalStateException e) { 9400668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi Log.e(TAG, "Failed to generate APF program.", e); 941578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen return; 942578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 943578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mLastTimeInstalledProgram = curTime(); 944578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mLastInstalledProgramMinLifetime = programMinLifetime; 94539c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti mLastInstalledProgram = program; 946059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti mNumProgramUpdates++; 947059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 9485ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti if (VDBG) { 9495ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti hexDump("Installing filter: ", program, program.length); 9505ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 951f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen mIpManagerCallback.installPacketFilter(program); 9524fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi int flags = ApfProgramEvent.flagsFor(mIPv4Address != null, mMulticastFilter); 9534fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi mMetricsLog.log(new ApfProgramEvent( 9544fc3ee5be223122792ebc0ee8a05c93d93e26a52Hugo Benichi programMinLifetime, rasToFilter.size(), mRas.size(), program.length, flags)); 955578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 956578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 957647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi /** 958647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi * Returns {@code true} if a new program should be installed because the current one dies soon. 959647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi */ 960647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi private boolean shouldInstallnewProgram() { 961578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen long expiry = mLastTimeInstalledProgram + mLastInstalledProgramMinLifetime; 962647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return expiry < curTime() + MAX_PROGRAM_LIFETIME_WORTH_REFRESHING; 963578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 964578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 965578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen private void hexDump(String msg, byte[] packet, int length) { 96639c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti log(msg + HexDump.toHexString(packet, 0, length, false /* lowercase */)); 967578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 968578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 969dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen @GuardedBy("this") 970dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen private void purgeExpiredRasLocked() { 971dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen for (int i = 0; i < mRas.size();) { 972dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen if (mRas.get(i).isExpired()) { 973dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen log("Expiring " + mRas.get(i)); 974dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen mRas.remove(i); 975dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } else { 976dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen i++; 977dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 978dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 979dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 980dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 981647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi /** 982647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi * Process an RA packet, updating the list of known RAs and installing a new APF program 983647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi * if the current APF program should be updated. 984647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi * @return a ProcessRaResult enum describing what action was performed. 985647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi */ 9860668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi @VisibleForTesting 9870668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi synchronized ProcessRaResult processRa(byte[] packet, int length) { 9885ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti if (VDBG) hexDump("Read packet = ", packet, length); 989578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 990578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Have we seen this RA before? 991578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen for (int i = 0; i < mRas.size(); i++) { 992578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen Ra ra = mRas.get(i); 993578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen if (ra.matches(packet, length)) { 9945ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti if (VDBG) log("matched RA " + ra); 995578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Update lifetimes. 996578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ra.mLastSeen = curTime(); 997578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen ra.mMinLifetime = ra.minLifetime(packet, length); 9985ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti ra.seenCount++; 999578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 1000578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Keep mRas in LRU order so as to prioritize generating filters for recently seen 1001578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // RAs. LRU prioritizes this because RA filters are generated in order from mRas 1002578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // until the filter program exceeds the maximum filter program size allowed by the 1003578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // chipset, so RAs appearing earlier in mRas are more likely to make it into the 1004578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // filter program. 1005578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // TODO: consider sorting the RAs in order of increasing expiry time as well. 1006578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // Swap to front of array. 1007578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mRas.add(0, mRas.remove(i)); 1008578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 1009647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi // If the current program doesn't expire for a while, don't update. 1010647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi if (shouldInstallnewProgram()) { 1011647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi installNewProgramLocked(); 1012647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return ProcessRaResult.UPDATE_EXPIRY; 1013647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 1014647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return ProcessRaResult.MATCH; 1015578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1016578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1017dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen purgeExpiredRasLocked(); 1018578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // TODO: figure out how to proceed when we've received more then MAX_RAS RAs. 1019647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi if (mRas.size() >= MAX_RAS) { 1020647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return ProcessRaResult.DROPPED; 1021647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 1022dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen final Ra ra; 1023578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen try { 1024dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen ra = new Ra(packet, length); 1025578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } catch (Exception e) { 10260668a61d82a424fb3714b6222f0e4213c18fc7b1Hugo Benichi Log.e(TAG, "Error parsing RA", e); 1027647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return ProcessRaResult.PARSE_ERROR; 1028578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1029dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen // Ignore 0 lifetime RAs. 1030647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi if (ra.isExpired()) { 1031647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return ProcessRaResult.ZERO_LIFETIME; 1032647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi } 1033dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen log("Adding " + ra); 1034dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen mRas.add(ra); 1035dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen installNewProgramLocked(); 1036647c86d70a0f2162dcc95854e9dccb925c16ecf3Hugo Benichi return ProcessRaResult.UPDATE_NEW_RA; 1037578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1038578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 1039578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen /** 1040f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen * Create an {@link ApfFilter} if {@code apfCapabilities} indicates support for packet 1041578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen * filtering using APF programs. 1042578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen */ 1043f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen public static ApfFilter maybeCreate(ApfCapabilities apfCapabilities, 10442e074db972355a77f91378b5b1daceb500dde019Paul Jensen NetworkInterface networkInterface, IpManager.Callback ipManagerCallback, 10452e074db972355a77f91378b5b1daceb500dde019Paul Jensen boolean multicastFilter) { 1046f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen if (apfCapabilities == null || networkInterface == null) return null; 1047f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen if (apfCapabilities.apfVersionSupported == 0) return null; 1048f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen if (apfCapabilities.maximumApfProgramSize < 512) { 1049f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen Log.e(TAG, "Unacceptably small APF limit: " + apfCapabilities.maximumApfProgramSize); 1050f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen return null; 1051578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1052578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // For now only support generating programs for Ethernet frames. If this restriction is 1053578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // lifted: 1054578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // 1. the program generator will need its offsets adjusted. 1055578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen // 2. the packet filter attached to our packet socket will need its offset adjusted. 1056f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen if (apfCapabilities.apfPacketFormat != ARPHRD_ETHER) return null; 1057f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen if (!new ApfGenerator().setApfVersion(apfCapabilities.apfVersionSupported)) { 1058f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen Log.e(TAG, "Unsupported APF version: " + apfCapabilities.apfVersionSupported); 1059f21b4dc1d6e9cc3fc164828e9eba33445c0801d0Paul Jensen return null; 1060578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 10616ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi return new ApfFilter(apfCapabilities, networkInterface, ipManagerCallback, 10626ccd51a338fed39217cb3a5c0f229ed547918634Hugo Benichi multicastFilter, new IpConnectivityLog()); 1063578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1064578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen 1065dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen public synchronized void shutdown() { 1066578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen if (mReceiveThread != null) { 10675ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti log("shutting down"); 1068578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mReceiveThread.halt(); // Also closes socket. 1069578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen mReceiveThread = null; 1070578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 1071dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen mRas.clear(); 1072dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 1073dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen 1074dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen public synchronized void setMulticastFilter(boolean enabled) { 1075dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen if (mMulticastFilter != enabled) { 1076dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen mMulticastFilter = enabled; 1077dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen installNewProgramLocked(); 1078dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen } 1079578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen } 10805ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 10817d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi /** Find the single IPv4 LinkAddress if there is one, otherwise return null. */ 10827d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private static LinkAddress findIPv4LinkAddress(LinkProperties lp) { 10837d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi LinkAddress ipv4Address = null; 10847d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi for (LinkAddress address : lp.getLinkAddresses()) { 10857d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi if (!(address.getAddress() instanceof Inet4Address)) { 10867d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi continue; 10877d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 10887d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi if (ipv4Address != null && !ipv4Address.isSameAddressAs(address)) { 10897d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi // More than one IPv4 address, abort. 10907d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return null; 10917d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 10927d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi ipv4Address = address; 1093a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen } 1094a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen return ipv4Address; 1095a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen } 1096a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 1097a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen public synchronized void setLinkProperties(LinkProperties lp) { 1098a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen // NOTE: Do not keep a copy of LinkProperties as it would further duplicate state. 10997d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi final LinkAddress ipv4Address = findIPv4LinkAddress(lp); 11007d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi final byte[] addr = (ipv4Address != null) ? ipv4Address.getAddress().getAddress() : null; 11017d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi final int prefix = (ipv4Address != null) ? ipv4Address.getPrefixLength() : 0; 11027d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi if ((prefix == mIPv4PrefixLength) && Arrays.equals(addr, mIPv4Address)) { 11037d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return; 11047d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11057d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi mIPv4Address = addr; 11067d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi mIPv4PrefixLength = prefix; 1107a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen installNewProgramLocked(); 1108a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen } 1109a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen 1110dfd5a949fbbba78793c261f5a0d585b27dc33851Paul Jensen public synchronized void dump(IndentingPrintWriter pw) { 1111059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti pw.println("Capabilities: " + mApfCapabilities); 11125ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.println("Receive thread: " + (mReceiveThread != null ? "RUNNING" : "STOPPED")); 1113059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti pw.println("Multicast: " + (mMulticastFilter ? "DROP" : "ALLOW")); 1114a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen try { 1115059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti pw.println("IPv4 address: " + InetAddress.getByAddress(mIPv4Address).getHostAddress()); 1116a8458c0363851c7324a8e64efe9f73d0bb6ef0b4Paul Jensen } catch (UnknownHostException|NullPointerException e) {} 1117059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti 11185ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti if (mLastTimeInstalledProgram == 0) { 11195ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.println("No program installed."); 11205ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti return; 11215ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 1122059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti pw.println("Program updates: " + mNumProgramUpdates); 11235ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.println(String.format( 1124059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti "Last program length %d, installed %ds ago, lifetime %ds", 112539c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti mLastInstalledProgram.length, curTime() - mLastTimeInstalledProgram, 11265ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti mLastInstalledProgramMinLifetime)); 11275ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti 11285ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.println("RA filters:"); 11295ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.increaseIndent(); 11305ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti for (Ra ra: mRas) { 11315ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.println(ra); 11325ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.increaseIndent(); 11335ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.println(String.format( 11345ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti "Seen: %d, last %ds ago", ra.seenCount, curTime() - ra.mLastSeen)); 113539c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti if (DBG) { 113639c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.println("Last match:"); 113739c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.increaseIndent(); 113839c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.println(ra.getLastMatchingPacket()); 113939c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.decreaseIndent(); 114039c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti } 11415ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti pw.decreaseIndent(); 11425ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 1143059e2bb376418aeb16551866c384dd1be032db62Lorenzo Colitti pw.decreaseIndent(); 114439c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti 114539c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti if (DBG) { 114639c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.println("Last program:"); 114739c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.increaseIndent(); 114839c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.println(HexDump.toHexString(mLastInstalledProgram, false /* lowercase */)); 114939c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti pw.decreaseIndent(); 115039c0d42f8120eae5f8c56a6acd223998a1debc3eLorenzo Colitti } 11515ff640d1f257c351a0e22e243532fecc4682f36dLorenzo Colitti } 11527d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11537d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private static int uint8(byte b) { 11547d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return b & 0xff; 11557d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11567d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11577d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private static int uint16(short s) { 11587d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return s & 0xffff; 11597d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11607d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11617d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private static long uint32(int i) { 11627d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return i & 0xffffffffL; 11637d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11647d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11657d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private static long getUint16(ByteBuffer buffer, int position) { 11667d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return uint16(buffer.getShort(position)); 11677d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11687d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11697d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi private static long getUint32(ByteBuffer buffer, int position) { 11707d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return uint32(buffer.getInt(position)); 11717d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11727d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11737d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi // TODO: move to android.net.NetworkUtils 11747d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi @VisibleForTesting 11757d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi public static int ipv4BroadcastAddress(byte[] addrBytes, int prefixLength) { 11767d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return bytesToInt(addrBytes) | (int) (uint32(-1) >>> prefixLength); 11777d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 11787d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi 11797d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi @VisibleForTesting 11807d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi public static int bytesToInt(byte[] addrBytes) { 11817d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi return (uint8(addrBytes[0]) << 24) 11827d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi + (uint8(addrBytes[1]) << 16) 11837d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi + (uint8(addrBytes[2]) << 8) 11847d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi + (uint8(addrBytes[3])); 11857d21eaedade0e01bed665dd2e4ba15e0c217237cHugo Benichi } 1186578a76e7de77492ac33e407fff4fb9a2f5550d8aPaul Jensen} 1187