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-rw-r--r--packages/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java744
1 files changed, 0 insertions, 744 deletions
diff --git a/packages/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java b/packages/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java
deleted file mode 100644
index 7c0b7cc7515c..000000000000
--- a/packages/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java
+++ /dev/null
@@ -1,744 +0,0 @@
-/*
- * Copyright (C) 2016 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package android.net.ip;
-
-import static android.net.util.NetworkConstants.IPV6_MIN_MTU;
-import static android.net.util.NetworkConstants.RFC7421_PREFIX_LENGTH;
-import static android.net.util.TetheringUtils.getAllNodesForScopeId;
-import static android.system.OsConstants.AF_INET6;
-import static android.system.OsConstants.IPPROTO_ICMPV6;
-import static android.system.OsConstants.SOCK_RAW;
-import static android.system.OsConstants.SOL_SOCKET;
-import static android.system.OsConstants.SO_SNDTIMEO;
-
-import android.net.IpPrefix;
-import android.net.LinkAddress;
-import android.net.TrafficStats;
-import android.net.util.InterfaceParams;
-import android.net.util.SocketUtils;
-import android.net.util.TetheringUtils;
-import android.system.ErrnoException;
-import android.system.Os;
-import android.system.StructTimeval;
-import android.util.Log;
-
-import com.android.internal.annotations.GuardedBy;
-import com.android.internal.util.TrafficStatsConstants;
-
-import java.io.FileDescriptor;
-import java.io.IOException;
-import java.net.Inet6Address;
-import java.net.InetAddress;
-import java.net.InetSocketAddress;
-import java.net.SocketException;
-import java.nio.BufferOverflowException;
-import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Iterator;
-import java.util.Map;
-import java.util.Random;
-import java.util.Set;
-import java.util.concurrent.atomic.AtomicInteger;
-
-
-/**
- * Basic IPv6 Router Advertisement Daemon.
- *
- * TODO:
- *
- * - Rewrite using Handler (and friends) so that AlarmManager can deliver
- * "kick" messages when it's time to send a multicast RA.
- *
- * @hide
- */
-public class RouterAdvertisementDaemon {
- private static final String TAG = RouterAdvertisementDaemon.class.getSimpleName();
- private static final byte ICMPV6_ND_ROUTER_SOLICIT = asByte(133);
- private static final byte ICMPV6_ND_ROUTER_ADVERT = asByte(134);
- private static final int MIN_RA_HEADER_SIZE = 16;
-
- // Summary of various timers and lifetimes.
- private static final int MIN_RTR_ADV_INTERVAL_SEC = 300;
- private static final int MAX_RTR_ADV_INTERVAL_SEC = 600;
- // In general, router, prefix, and DNS lifetimes are all advised to be
- // greater than or equal to 3 * MAX_RTR_ADV_INTERVAL. Here, we double
- // that to allow for multicast packet loss.
- //
- // This MAX_RTR_ADV_INTERVAL_SEC and DEFAULT_LIFETIME are also consistent
- // with the https://tools.ietf.org/html/rfc7772#section-4 discussion of
- // "approximately 7 RAs per hour".
- private static final int DEFAULT_LIFETIME = 6 * MAX_RTR_ADV_INTERVAL_SEC;
- // From https://tools.ietf.org/html/rfc4861#section-10 .
- private static final int MIN_DELAY_BETWEEN_RAS_SEC = 3;
- // Both initial and final RAs, but also for changes in RA contents.
- // From https://tools.ietf.org/html/rfc4861#section-10 .
- private static final int MAX_URGENT_RTR_ADVERTISEMENTS = 5;
-
- private static final int DAY_IN_SECONDS = 86_400;
-
- private final InterfaceParams mInterface;
- private final InetSocketAddress mAllNodes;
-
- // This lock is to protect the RA from being updated while being
- // transmitted on another thread (multicast or unicast).
- //
- // TODO: This should be handled with a more RCU-like approach.
- private final Object mLock = new Object();
- @GuardedBy("mLock")
- private final byte[] mRA = new byte[IPV6_MIN_MTU];
- @GuardedBy("mLock")
- private int mRaLength;
- @GuardedBy("mLock")
- private final DeprecatedInfoTracker mDeprecatedInfoTracker;
- @GuardedBy("mLock")
- private RaParams mRaParams;
-
- private volatile FileDescriptor mSocket;
- private volatile MulticastTransmitter mMulticastTransmitter;
- private volatile UnicastResponder mUnicastResponder;
-
- /** Encapsulate the RA parameters for RouterAdvertisementDaemon.*/
- public static class RaParams {
- // Tethered traffic will have the hop limit properly decremented.
- // Consequently, set the hoplimit greater by one than the upstream
- // unicast hop limit.
- //
- // TODO: Dynamically pass down the IPV6_UNICAST_HOPS value from the
- // upstream interface for more correct behaviour.
- static final byte DEFAULT_HOPLIMIT = 65;
-
- public boolean hasDefaultRoute;
- public byte hopLimit;
- public int mtu;
- public HashSet<IpPrefix> prefixes;
- public HashSet<Inet6Address> dnses;
-
- public RaParams() {
- hasDefaultRoute = false;
- hopLimit = DEFAULT_HOPLIMIT;
- mtu = IPV6_MIN_MTU;
- prefixes = new HashSet<IpPrefix>();
- dnses = new HashSet<Inet6Address>();
- }
-
- public RaParams(RaParams other) {
- hasDefaultRoute = other.hasDefaultRoute;
- hopLimit = other.hopLimit;
- mtu = other.mtu;
- prefixes = (HashSet) other.prefixes.clone();
- dnses = (HashSet) other.dnses.clone();
- }
-
- /**
- * Returns the subset of RA parameters that become deprecated when
- * moving from announcing oldRa to announcing newRa.
- *
- * Currently only tracks differences in |prefixes| and |dnses|.
- */
- public static RaParams getDeprecatedRaParams(RaParams oldRa, RaParams newRa) {
- RaParams newlyDeprecated = new RaParams();
-
- if (oldRa != null) {
- for (IpPrefix ipp : oldRa.prefixes) {
- if (newRa == null || !newRa.prefixes.contains(ipp)) {
- newlyDeprecated.prefixes.add(ipp);
- }
- }
-
- for (Inet6Address dns : oldRa.dnses) {
- if (newRa == null || !newRa.dnses.contains(dns)) {
- newlyDeprecated.dnses.add(dns);
- }
- }
- }
-
- return newlyDeprecated;
- }
- }
-
- private static class DeprecatedInfoTracker {
- private final HashMap<IpPrefix, Integer> mPrefixes = new HashMap<>();
- private final HashMap<Inet6Address, Integer> mDnses = new HashMap<>();
-
- Set<IpPrefix> getPrefixes() {
- return mPrefixes.keySet();
- }
-
- void putPrefixes(Set<IpPrefix> prefixes) {
- for (IpPrefix ipp : prefixes) {
- mPrefixes.put(ipp, MAX_URGENT_RTR_ADVERTISEMENTS);
- }
- }
-
- void removePrefixes(Set<IpPrefix> prefixes) {
- for (IpPrefix ipp : prefixes) {
- mPrefixes.remove(ipp);
- }
- }
-
- Set<Inet6Address> getDnses() {
- return mDnses.keySet();
- }
-
- void putDnses(Set<Inet6Address> dnses) {
- for (Inet6Address dns : dnses) {
- mDnses.put(dns, MAX_URGENT_RTR_ADVERTISEMENTS);
- }
- }
-
- void removeDnses(Set<Inet6Address> dnses) {
- for (Inet6Address dns : dnses) {
- mDnses.remove(dns);
- }
- }
-
- boolean isEmpty() {
- return mPrefixes.isEmpty() && mDnses.isEmpty();
- }
-
- private boolean decrementCounters() {
- boolean removed = decrementCounter(mPrefixes);
- removed |= decrementCounter(mDnses);
- return removed;
- }
-
- private <T> boolean decrementCounter(HashMap<T, Integer> map) {
- boolean removed = false;
-
- for (Iterator<Map.Entry<T, Integer>> it = map.entrySet().iterator();
- it.hasNext();) {
- Map.Entry<T, Integer> kv = it.next();
- if (kv.getValue() == 0) {
- it.remove();
- removed = true;
- } else {
- kv.setValue(kv.getValue() - 1);
- }
- }
-
- return removed;
- }
- }
-
- public RouterAdvertisementDaemon(InterfaceParams ifParams) {
- mInterface = ifParams;
- mAllNodes = new InetSocketAddress(getAllNodesForScopeId(mInterface.index), 0);
- mDeprecatedInfoTracker = new DeprecatedInfoTracker();
- }
-
- /** Build new RA.*/
- public void buildNewRa(RaParams deprecatedParams, RaParams newParams) {
- synchronized (mLock) {
- if (deprecatedParams != null) {
- mDeprecatedInfoTracker.putPrefixes(deprecatedParams.prefixes);
- mDeprecatedInfoTracker.putDnses(deprecatedParams.dnses);
- }
-
- if (newParams != null) {
- // Process information that is no longer deprecated.
- mDeprecatedInfoTracker.removePrefixes(newParams.prefixes);
- mDeprecatedInfoTracker.removeDnses(newParams.dnses);
- }
-
- mRaParams = newParams;
- assembleRaLocked();
- }
-
- maybeNotifyMulticastTransmitter();
- }
-
- /** Start router advertisement daemon. */
- public boolean start() {
- if (!createSocket()) {
- return false;
- }
-
- mMulticastTransmitter = new MulticastTransmitter();
- mMulticastTransmitter.start();
-
- mUnicastResponder = new UnicastResponder();
- mUnicastResponder.start();
-
- return true;
- }
-
- /** Stop router advertisement daemon. */
- public void stop() {
- closeSocket();
- // Wake up mMulticastTransmitter thread to interrupt a potential 1 day sleep before
- // the thread's termination.
- maybeNotifyMulticastTransmitter();
- mMulticastTransmitter = null;
- mUnicastResponder = null;
- }
-
- @GuardedBy("mLock")
- private void assembleRaLocked() {
- final ByteBuffer ra = ByteBuffer.wrap(mRA);
- ra.order(ByteOrder.BIG_ENDIAN);
-
- final boolean haveRaParams = (mRaParams != null);
- boolean shouldSendRA = false;
-
- try {
- putHeader(ra, haveRaParams && mRaParams.hasDefaultRoute,
- haveRaParams ? mRaParams.hopLimit : RaParams.DEFAULT_HOPLIMIT);
- putSlla(ra, mInterface.macAddr.toByteArray());
- mRaLength = ra.position();
-
- // https://tools.ietf.org/html/rfc5175#section-4 says:
- //
- // "MUST NOT be added to a Router Advertisement message
- // if no flags in the option are set."
- //
- // putExpandedFlagsOption(ra);
-
- if (haveRaParams) {
- putMtu(ra, mRaParams.mtu);
- mRaLength = ra.position();
-
- for (IpPrefix ipp : mRaParams.prefixes) {
- putPio(ra, ipp, DEFAULT_LIFETIME, DEFAULT_LIFETIME);
- mRaLength = ra.position();
- shouldSendRA = true;
- }
-
- if (mRaParams.dnses.size() > 0) {
- putRdnss(ra, mRaParams.dnses, DEFAULT_LIFETIME);
- mRaLength = ra.position();
- shouldSendRA = true;
- }
- }
-
- for (IpPrefix ipp : mDeprecatedInfoTracker.getPrefixes()) {
- putPio(ra, ipp, 0, 0);
- mRaLength = ra.position();
- shouldSendRA = true;
- }
-
- final Set<Inet6Address> deprecatedDnses = mDeprecatedInfoTracker.getDnses();
- if (!deprecatedDnses.isEmpty()) {
- putRdnss(ra, deprecatedDnses, 0);
- mRaLength = ra.position();
- shouldSendRA = true;
- }
- } catch (BufferOverflowException e) {
- // The packet up to mRaLength is valid, since it has been updated
- // progressively as the RA was built. Log an error, and continue
- // on as best as possible.
- Log.e(TAG, "Could not construct new RA: " + e);
- }
-
- // We have nothing worth announcing; indicate as much to maybeSendRA().
- if (!shouldSendRA) {
- mRaLength = 0;
- }
- }
-
- private void maybeNotifyMulticastTransmitter() {
- final MulticastTransmitter m = mMulticastTransmitter;
- if (m != null) {
- m.hup();
- }
- }
-
- private static byte asByte(int value) {
- return (byte) value;
- }
- private static short asShort(int value) {
- return (short) value;
- }
-
- private static void putHeader(ByteBuffer ra, boolean hasDefaultRoute, byte hopLimit) {
- /**
- Router Advertisement Message Format
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Code | Checksum |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Cur Hop Limit |M|O|H|Prf|P|R|R| Router Lifetime |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Reachable Time |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Retrans Timer |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Options ...
- +-+-+-+-+-+-+-+-+-+-+-+-
- */
- ra.put(ICMPV6_ND_ROUTER_ADVERT)
- .put(asByte(0))
- .putShort(asShort(0))
- .put(hopLimit)
- // RFC 4191 "high" preference, iff. advertising a default route.
- .put(hasDefaultRoute ? asByte(0x08) : asByte(0))
- .putShort(hasDefaultRoute ? asShort(DEFAULT_LIFETIME) : asShort(0))
- .putInt(0)
- .putInt(0);
- }
-
- private static void putSlla(ByteBuffer ra, byte[] slla) {
- /**
- Source/Target Link-layer Address
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Length | Link-Layer Address ...
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
- if (slla == null || slla.length != 6) {
- // Only IEEE 802.3 6-byte addresses are supported.
- return;
- }
-
- final byte nd_option_slla = 1;
- final byte slla_num_8octets = 1;
- ra.put(nd_option_slla)
- .put(slla_num_8octets)
- .put(slla);
- }
-
- private static void putExpandedFlagsOption(ByteBuffer ra) {
- /**
- Router Advertisement Expanded Flags Option
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Length | Bit fields available ..
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- ... for assignment |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
-
- final byte nd_option__efo = 26;
- final byte efo_num_8octets = 1;
-
- ra.put(nd_option__efo)
- .put(efo_num_8octets)
- .putShort(asShort(0))
- .putInt(0);
- }
-
- private static void putMtu(ByteBuffer ra, int mtu) {
- /**
- MTU
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Length | Reserved |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | MTU |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
- final byte nd_option_mtu = 5;
- final byte mtu_num_8octs = 1;
- ra.put(nd_option_mtu)
- .put(mtu_num_8octs)
- .putShort(asShort(0))
- .putInt((mtu < IPV6_MIN_MTU) ? IPV6_MIN_MTU : mtu);
- }
-
- private static void putPio(ByteBuffer ra, IpPrefix ipp,
- int validTime, int preferredTime) {
- /**
- Prefix Information
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Length | Prefix Length |L|A| Reserved1 |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Valid Lifetime |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Preferred Lifetime |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Reserved2 |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | |
- + +
- | |
- + Prefix +
- | |
- + +
- | |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
- final int prefixLength = ipp.getPrefixLength();
- if (prefixLength != 64) {
- return;
- }
- final byte nd_option_pio = 3;
- final byte pio_num_8octets = 4;
-
- if (validTime < 0) validTime = 0;
- if (preferredTime < 0) preferredTime = 0;
- if (preferredTime > validTime) preferredTime = validTime;
-
- final byte[] addr = ipp.getAddress().getAddress();
- ra.put(nd_option_pio)
- .put(pio_num_8octets)
- .put(asByte(prefixLength))
- .put(asByte(0xc0)) /* L & A set */
- .putInt(validTime)
- .putInt(preferredTime)
- .putInt(0)
- .put(addr);
- }
-
- private static void putRio(ByteBuffer ra, IpPrefix ipp) {
- /**
- Route Information Option
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Length | Prefix Length |Resvd|Prf|Resvd|
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Route Lifetime |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Prefix (Variable Length) |
- . .
- . .
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
- final int prefixLength = ipp.getPrefixLength();
- if (prefixLength > 64) {
- return;
- }
- final byte nd_option_rio = 24;
- final byte rio_num_8octets = asByte(
- (prefixLength == 0) ? 1 : (prefixLength <= 8) ? 2 : 3);
-
- final byte[] addr = ipp.getAddress().getAddress();
- ra.put(nd_option_rio)
- .put(rio_num_8octets)
- .put(asByte(prefixLength))
- .put(asByte(0x18))
- .putInt(DEFAULT_LIFETIME);
-
- // Rely upon an IpPrefix's address being properly zeroed.
- if (prefixLength > 0) {
- ra.put(addr, 0, (prefixLength <= 64) ? 8 : 16);
- }
- }
-
- private static void putRdnss(ByteBuffer ra, Set<Inet6Address> dnses, int lifetime) {
- /**
- Recursive DNS Server (RDNSS) Option
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Type | Length | Reserved |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Lifetime |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | |
- : Addresses of IPv6 Recursive DNS Servers :
- | |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- */
-
- final HashSet<Inet6Address> filteredDnses = new HashSet<>();
- for (Inet6Address dns : dnses) {
- if ((new LinkAddress(dns, RFC7421_PREFIX_LENGTH)).isGlobalPreferred()) {
- filteredDnses.add(dns);
- }
- }
- if (filteredDnses.isEmpty()) return;
-
- final byte nd_option_rdnss = 25;
- final byte rdnss_num_8octets = asByte(dnses.size() * 2 + 1);
- ra.put(nd_option_rdnss)
- .put(rdnss_num_8octets)
- .putShort(asShort(0))
- .putInt(lifetime);
-
- for (Inet6Address dns : filteredDnses) {
- // NOTE: If the full of list DNS servers doesn't fit in the packet,
- // this code will cause a buffer overflow and the RA won't include
- // this instance of the option at all.
- //
- // TODO: Consider looking at ra.remaining() to determine how many
- // DNS servers will fit, and adding only those.
- ra.put(dns.getAddress());
- }
- }
-
- private boolean createSocket() {
- final int send_timout_ms = 300;
-
- final int oldTag = TrafficStats.getAndSetThreadStatsTag(
- TrafficStatsConstants.TAG_SYSTEM_NEIGHBOR);
- try {
- mSocket = Os.socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
- // Setting SNDTIMEO is purely for defensive purposes.
- Os.setsockoptTimeval(
- mSocket, SOL_SOCKET, SO_SNDTIMEO, StructTimeval.fromMillis(send_timout_ms));
- SocketUtils.bindSocketToInterface(mSocket, mInterface.name);
- TetheringUtils.setupRaSocket(mSocket, mInterface.index);
- } catch (ErrnoException | IOException e) {
- Log.e(TAG, "Failed to create RA daemon socket: " + e);
- return false;
- } finally {
- TrafficStats.setThreadStatsTag(oldTag);
- }
-
- return true;
- }
-
- private void closeSocket() {
- if (mSocket != null) {
- try {
- SocketUtils.closeSocket(mSocket);
- } catch (IOException ignored) { }
- }
- mSocket = null;
- }
-
- private boolean isSocketValid() {
- final FileDescriptor s = mSocket;
- return (s != null) && s.valid();
- }
-
- private boolean isSuitableDestination(InetSocketAddress dest) {
- if (mAllNodes.equals(dest)) {
- return true;
- }
-
- final InetAddress destip = dest.getAddress();
- return (destip instanceof Inet6Address)
- && destip.isLinkLocalAddress()
- && (((Inet6Address) destip).getScopeId() == mInterface.index);
- }
-
- private void maybeSendRA(InetSocketAddress dest) {
- if (dest == null || !isSuitableDestination(dest)) {
- dest = mAllNodes;
- }
-
- try {
- synchronized (mLock) {
- if (mRaLength < MIN_RA_HEADER_SIZE) {
- // No actual RA to send.
- return;
- }
- Os.sendto(mSocket, mRA, 0, mRaLength, 0, dest);
- }
- Log.d(TAG, "RA sendto " + dest.getAddress().getHostAddress());
- } catch (ErrnoException | SocketException e) {
- if (isSocketValid()) {
- Log.e(TAG, "sendto error: " + e);
- }
- }
- }
-
- private final class UnicastResponder extends Thread {
- private final InetSocketAddress mSolicitor = new InetSocketAddress(0);
- // The recycled buffer for receiving Router Solicitations from clients.
- // If the RS is larger than IPV6_MIN_MTU the packets are truncated.
- // This is fine since currently only byte 0 is examined anyway.
- private final byte[] mSolicitation = new byte[IPV6_MIN_MTU];
-
- @Override
- public void run() {
- while (isSocketValid()) {
- try {
- // Blocking receive.
- final int rval = Os.recvfrom(
- mSocket, mSolicitation, 0, mSolicitation.length, 0, mSolicitor);
- // Do the least possible amount of validation.
- if (rval < 1 || mSolicitation[0] != ICMPV6_ND_ROUTER_SOLICIT) {
- continue;
- }
- } catch (ErrnoException | SocketException e) {
- if (isSocketValid()) {
- Log.e(TAG, "recvfrom error: " + e);
- }
- continue;
- }
-
- maybeSendRA(mSolicitor);
- }
- }
- }
-
- // TODO: Consider moving this to run on a provided Looper as a Handler,
- // with WakeupMessage-style messages providing the timer driven input.
- private final class MulticastTransmitter extends Thread {
- private final Random mRandom = new Random();
- private final AtomicInteger mUrgentAnnouncements = new AtomicInteger(0);
-
- @Override
- public void run() {
- while (isSocketValid()) {
- try {
- Thread.sleep(getNextMulticastTransmitDelayMs());
- } catch (InterruptedException ignored) {
- // Stop sleeping, immediately send an RA, and continue.
- }
-
- maybeSendRA(mAllNodes);
- synchronized (mLock) {
- if (mDeprecatedInfoTracker.decrementCounters()) {
- // At least one deprecated PIO has been removed;
- // reassemble the RA.
- assembleRaLocked();
- }
- }
- }
- }
-
- public void hup() {
- // Set to one fewer that the desired number, because as soon as
- // the thread interrupt is processed we immediately send an RA
- // and mUrgentAnnouncements is not examined until the subsequent
- // sleep interval computation (i.e. this way we send 3 and not 4).
- mUrgentAnnouncements.set(MAX_URGENT_RTR_ADVERTISEMENTS - 1);
- interrupt();
- }
-
- private int getNextMulticastTransmitDelaySec() {
- boolean deprecationInProgress = false;
- synchronized (mLock) {
- if (mRaLength < MIN_RA_HEADER_SIZE) {
- // No actual RA to send; just sleep for 1 day.
- return DAY_IN_SECONDS;
- }
- deprecationInProgress = !mDeprecatedInfoTracker.isEmpty();
- }
-
- final int urgentPending = mUrgentAnnouncements.getAndDecrement();
- if ((urgentPending > 0) || deprecationInProgress) {
- return MIN_DELAY_BETWEEN_RAS_SEC;
- }
-
- return MIN_RTR_ADV_INTERVAL_SEC + mRandom.nextInt(
- MAX_RTR_ADV_INTERVAL_SEC - MIN_RTR_ADV_INTERVAL_SEC);
- }
-
- private long getNextMulticastTransmitDelayMs() {
- return 1000 * (long) getNextMulticastTransmitDelaySec();
- }
- }
-}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-03 11:17:21 +0000