#include <net/if.h>
#include <linux/filter.h>
#include <linux/if.h>
+#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <net/if_ether.h>
+#include <netinet/icmp6.h>
#include <netinet/ip.h>
+#include <netinet/ip6.h>
#include <netinet/udp.h>
#include <cutils/properties.h>
static void android_net_utils_attachDhcpFilter(JNIEnv *env, jobject clazz, jobject javaFd)
{
- int fd = jniGetFDFromFileDescriptor(env, javaFd);
uint32_t ip_offset = sizeof(ether_header);
uint32_t proto_offset = ip_offset + offsetof(iphdr, protocol);
- uint32_t flags_offset = ip_offset + offsetof(iphdr, frag_off);
+ uint32_t flags_offset = ip_offset + offsetof(iphdr, frag_off);
uint32_t dport_indirect_offset = ip_offset + offsetof(udphdr, dest);
struct sock_filter filter_code[] = {
// Check the protocol is UDP.
filter_code,
};
+ int fd = jniGetFDFromFileDescriptor(env, javaFd);
+ if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)) != 0) {
+ jniThrowExceptionFmt(env, "java/net/SocketException",
+ "setsockopt(SO_ATTACH_FILTER): %s", strerror(errno));
+ }
+}
+
+static void android_net_utils_attachRaFilter(JNIEnv *env, jobject clazz, jobject javaFd,
+ jint hardwareAddressType)
+{
+ if (hardwareAddressType != ARPHRD_ETHER) {
+ jniThrowExceptionFmt(env, "java/net/SocketException",
+ "attachRaFilter only supports ARPHRD_ETHER");
+ return;
+ }
+
+ uint32_t ipv6_offset = sizeof(ether_header);
+ uint32_t ipv6_next_header_offset = ipv6_offset + offsetof(ip6_hdr, ip6_nxt);
+ uint32_t icmp6_offset = ipv6_offset + sizeof(ip6_hdr);
+ uint32_t icmp6_type_offset = icmp6_offset + offsetof(icmp6_hdr, icmp6_type);
+ struct sock_filter filter_code[] = {
+ // Check IPv6 Next Header is ICMPv6.
+ BPF_STMT(BPF_LD | BPF_B | BPF_ABS, ipv6_next_header_offset),
+ BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, IPPROTO_ICMPV6, 0, 3),
+
+ // Check ICMPv6 type is Router Advertisement.
+ BPF_STMT(BPF_LD | BPF_B | BPF_ABS, icmp6_type_offset),
+ BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, ND_ROUTER_ADVERT, 0, 1),
+
+ // Accept or reject.
+ BPF_STMT(BPF_RET | BPF_K, 0xffff),
+ BPF_STMT(BPF_RET | BPF_K, 0)
+ };
+ struct sock_fprog filter = {
+ sizeof(filter_code) / sizeof(filter_code[0]),
+ filter_code,
+ };
+
+ int fd = jniGetFDFromFileDescriptor(env, javaFd);
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)) != 0) {
jniThrowExceptionFmt(env, "java/net/SocketException",
"setsockopt(SO_ATTACH_FILTER): %s", strerror(errno));
{ "protectFromVpn", "(I)Z", (void*)android_net_utils_protectFromVpn },
{ "queryUserAccess", "(II)Z", (void*)android_net_utils_queryUserAccess },
{ "attachDhcpFilter", "(Ljava/io/FileDescriptor;)V", (void*) android_net_utils_attachDhcpFilter },
+ { "attachRaFilter", "(Ljava/io/FileDescriptor;I)V", (void*) android_net_utils_attachRaFilter },
};
int register_android_net_NetworkUtils(JNIEnv* env)
--- /dev/null
+/*
+ * 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 com.android.server.connectivity;
+
+import static android.system.OsConstants.*;
+
+import android.net.NetworkUtils;
+import android.net.apf.ApfGenerator;
+import android.net.apf.ApfGenerator.IllegalInstructionException;
+import android.net.apf.ApfGenerator.Register;
+import android.system.ErrnoException;
+import android.system.Os;
+import android.system.PacketSocketAddress;
+import android.util.Log;
+import android.util.Pair;
+
+import com.android.internal.util.HexDump;
+import com.android.server.ConnectivityService;
+
+import java.io.FileDescriptor;
+import java.io.IOException;
+import java.lang.Thread;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Arrays;
+
+import libcore.io.IoBridge;
+
+/**
+ * For networks that support packet filtering via APF programs, {@code ApfFilter}
+ * listens for IPv6 ICMPv6 router advertisements (RAs) and generates APF programs to
+ * filter out redundant duplicate ones.
+ *
+ * @hide
+ */
+public class ApfFilter {
+ // Thread to listen for RAs.
+ private class ReceiveThread extends Thread {
+ private final byte[] mPacket = new byte[1514];
+ private final FileDescriptor mSocket;
+ private volatile boolean mStopped;
+
+ public ReceiveThread(FileDescriptor socket) {
+ mSocket = socket;
+ }
+
+ public void halt() {
+ mStopped = true;
+ try {
+ // Interrupts the read() call the thread is blocked in.
+ IoBridge.closeAndSignalBlockedThreads(mSocket);
+ } catch (IOException ignored) {}
+ }
+
+ @Override
+ public void run() {
+ log("begin monitoring");
+ while (!mStopped) {
+ try {
+ int length = Os.read(mSocket, mPacket, 0, mPacket.length);
+ processRa(mPacket, length);
+ } catch (IOException|ErrnoException e) {
+ if (!mStopped) {
+ Log.e(TAG, "Read error", e);
+ }
+ }
+ }
+ }
+ }
+
+ private static final String TAG = "ApfFilter";
+
+ private final ConnectivityService mConnectivityService;
+ private final NetworkAgentInfo mNai;
+ private ReceiveThread mReceiveThread;
+ private String mIfaceName;
+ private long mUniqueCounter;
+
+ private ApfFilter(ConnectivityService connectivityService, NetworkAgentInfo nai) {
+ mConnectivityService = connectivityService;
+ mNai = nai;
+ maybeStartFilter();
+ }
+
+ private void log(String s) {
+ Log.d(TAG, "(" + mNai.network.netId + "): " + s);
+ }
+
+ private long getUniqueNumber() {
+ return mUniqueCounter++;
+ }
+
+ /**
+ * Attempt to start listening for RAs and, if RAs are received, generating and installing
+ * filters to ignore useless RAs.
+ */
+ private void maybeStartFilter() {
+ mIfaceName = mNai.linkProperties.getInterfaceName();
+ if (mIfaceName == null) return;
+ FileDescriptor socket;
+ try {
+ socket = Os.socket(AF_PACKET, SOCK_RAW, ETH_P_IPV6);
+ PacketSocketAddress addr = new PacketSocketAddress((short) ETH_P_IPV6,
+ NetworkInterface.getByName(mIfaceName).getIndex());
+ Os.bind(socket, addr);
+ NetworkUtils.attachRaFilter(socket, mNai.networkMisc.apfPacketFormat);
+ } catch(SocketException|ErrnoException e) {
+ Log.e(TAG, "Error filtering raw socket", e);
+ return;
+ }
+ mReceiveThread = new ReceiveThread(socket);
+ mReceiveThread.start();
+ }
+
+ /**
+ * mNai's LinkProperties may have changed, take appropriate action.
+ */
+ public void updateFilter() {
+ // If we're not listening for RAs, try starting.
+ if (mReceiveThread == null) {
+ maybeStartFilter();
+ // If interface name has changed, restart.
+ } else if (!mIfaceName.equals(mNai.linkProperties.getInterfaceName())) {
+ shutdown();
+ maybeStartFilter();
+ }
+ }
+
+ // Returns seconds since Unix Epoch.
+ private static long curTime() {
+ return System.currentTimeMillis() / 1000L;
+ }
+
+ // A class to hold information about an RA.
+ private class Ra {
+ private static final int ETH_HEADER_LEN = 14;
+
+ private static final int IPV6_HEADER_LEN = 40;
+
+ // From RFC4861:
+ private static final int ICMP6_RA_HEADER_LEN = 16;
+ private static final int ICMP6_RA_OPTION_OFFSET =
+ ETH_HEADER_LEN + IPV6_HEADER_LEN + ICMP6_RA_HEADER_LEN;
+ private static final int ICMP6_RA_ROUTER_LIFETIME_OFFSET =
+ ETH_HEADER_LEN + IPV6_HEADER_LEN + 6;
+ private static final int ICMP6_RA_ROUTER_LIFETIME_LEN = 2;
+ // Prefix information option.
+ private static final int ICMP6_PREFIX_OPTION_TYPE = 3;
+ private static final int ICMP6_PREFIX_OPTION_LEN = 32;
+ private static final int ICMP6_PREFIX_OPTION_VALID_LIFETIME_OFFSET = 4;
+ private static final int ICMP6_PREFIX_OPTION_VALID_LIFETIME_LEN = 4;
+ private static final int ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_OFFSET = 8;
+ private static final int ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_LEN = 4;
+
+ // From RFC6106: Recursive DNS Server option
+ private static final int ICMP6_RDNSS_OPTION_TYPE = 25;
+ // From RFC6106: DNS Search List option
+ private static final int ICMP6_DNSSL_OPTION_TYPE = 31;
+
+ // From RFC4191: Route Information option
+ private static final int ICMP6_ROUTE_INFO_OPTION_TYPE = 24;
+ // Above three options all have the same format:
+ private static final int ICMP6_4_BYTE_LIFETIME_OFFSET = 4;
+ private static final int ICMP6_4_BYTE_LIFETIME_LEN = 4;
+
+ private final ByteBuffer mPacket;
+ // List of binary ranges that include the whole packet except the lifetimes.
+ // Pairs consist of offset and length.
+ private final ArrayList<Pair<Integer, Integer>> mNonLifetimes =
+ new ArrayList<Pair<Integer, Integer>>();
+ // Minimum lifetime in packet
+ long mMinLifetime;
+ // When the packet was last captured, in seconds since Unix Epoch
+ long mLastSeen;
+
+ /**
+ * Add a binary range of the packet that does not include a lifetime to mNonLifetimes.
+ * Assumes mPacket.position() is as far as we've parsed the packet.
+ * @param lastNonLifetimeStart offset within packet of where the last binary range of
+ * data not including a lifetime.
+ * @param lifetimeOffset offset from mPacket.position() to the next lifetime data.
+ * @param lifetimeLength length of the next lifetime data.
+ * @return offset within packet of where the next binary range of data not including
+ * a lifetime. This can be passed into the next invocation of this function
+ * via {@code lastNonLifetimeStart}.
+ */
+ private int addNonLifetime(int lastNonLifetimeStart, int lifetimeOffset,
+ int lifetimeLength) {
+ lifetimeOffset += mPacket.position();
+ mNonLifetimes.add(new Pair<Integer, Integer>(lastNonLifetimeStart,
+ lifetimeOffset - lastNonLifetimeStart));
+ return lifetimeOffset + lifetimeLength;
+ }
+
+ // Note that this parses RA and may throw IllegalArgumentException (from
+ // Buffer.position(int) ) or IndexOutOfBoundsException (from ByteBuffer.get(int) ) if
+ // parsing encounters something non-compliant with specifications.
+ Ra(byte[] packet, int length) {
+ mPacket = ByteBuffer.allocate(length).put(ByteBuffer.wrap(packet, 0, length));
+ mPacket.clear();
+ mLastSeen = curTime();
+
+ // Parse router lifetime
+ int lastNonLifetimeStart = addNonLifetime(0, ICMP6_RA_ROUTER_LIFETIME_OFFSET,
+ ICMP6_RA_ROUTER_LIFETIME_LEN);
+ // Parse ICMP6 options
+ mPacket.position(ICMP6_RA_OPTION_OFFSET);
+ while (mPacket.hasRemaining()) {
+ int optionType = ((int)mPacket.get(mPacket.position())) & 0xff;
+ int optionLength = (((int)mPacket.get(mPacket.position() + 1)) & 0xff) * 8;
+ switch (optionType) {
+ case ICMP6_PREFIX_OPTION_TYPE:
+ // Parse valid lifetime
+ lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart,
+ ICMP6_PREFIX_OPTION_VALID_LIFETIME_OFFSET,
+ ICMP6_PREFIX_OPTION_VALID_LIFETIME_LEN);
+ // Parse preferred lifetime
+ lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart,
+ ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_OFFSET,
+ ICMP6_PREFIX_OPTION_PREFERRED_LIFETIME_LEN);
+ break;
+ // These three options have the same lifetime offset and size, so process
+ // together:
+ case ICMP6_ROUTE_INFO_OPTION_TYPE:
+ case ICMP6_RDNSS_OPTION_TYPE:
+ case ICMP6_DNSSL_OPTION_TYPE:
+ // Parse lifetime
+ lastNonLifetimeStart = addNonLifetime(lastNonLifetimeStart,
+ ICMP6_4_BYTE_LIFETIME_OFFSET,
+ ICMP6_4_BYTE_LIFETIME_LEN);
+ break;
+ default:
+ // RFC4861 section 4.2 dictates we ignore unknown options for fowards
+ // compatibility.
+ break;
+ }
+ mPacket.position(mPacket.position() + optionLength);
+ }
+ // Mark non-lifetime bytes since last lifetime.
+ addNonLifetime(lastNonLifetimeStart, 0, 0);
+ mMinLifetime = minLifetime(packet, length);
+ }
+
+ // Ignoring lifetimes (which may change) does {@code packet} match this RA?
+ boolean matches(byte[] packet, int length) {
+ if (length != mPacket.limit()) return false;
+ ByteBuffer a = ByteBuffer.wrap(packet);
+ ByteBuffer b = mPacket;
+ for (Pair<Integer, Integer> nonLifetime : mNonLifetimes) {
+ a.clear();
+ b.clear();
+ a.position(nonLifetime.first);
+ b.position(nonLifetime.first);
+ a.limit(nonLifetime.first + nonLifetime.second);
+ b.limit(nonLifetime.first + nonLifetime.second);
+ if (a.compareTo(b) != 0) return false;
+ }
+ return true;
+ }
+
+ // What is the minimum of all lifetimes within {@code packet} in seconds?
+ // Precondition: matches(packet, length) already returned true.
+ long minLifetime(byte[] packet, int length) {
+ long minLifetime = Long.MAX_VALUE;
+ // Wrap packet in ByteBuffer so we can read big-endian values easily
+ ByteBuffer byteBuffer = ByteBuffer.wrap(packet);
+ for (int i = 0; (i + 1) < mNonLifetimes.size(); i++) {
+ int offset = mNonLifetimes.get(i).first + mNonLifetimes.get(i).second;
+ int lifetimeLength = mNonLifetimes.get(i+1).first - offset;
+ long val;
+ switch (lifetimeLength) {
+ case 2: val = byteBuffer.getShort(offset); break;
+ case 4: val = byteBuffer.getInt(offset); break;
+ default: throw new IllegalStateException("bogus lifetime size " + length);
+ }
+ // Mask to size, converting signed to unsigned
+ val &= (1L << (lifetimeLength * 8)) - 1;
+ minLifetime = Math.min(minLifetime, val);
+ }
+ return minLifetime;
+ }
+
+ // How many seconds does this RA's have to live, taking into account the fact
+ // that we might have seen it a while ago.
+ long currentLifetime() {
+ return mMinLifetime - (curTime() - mLastSeen);
+ }
+
+ boolean isExpired() {
+ return currentLifetime() < 0;
+ }
+
+ // Append a filter for this RA to {@code gen}. Jump to DROP_LABEL if it should be dropped.
+ // Jump to the next filter if packet doesn't match this RA.
+ long generateFilter(ApfGenerator gen) throws IllegalInstructionException {
+ String nextFilterLabel = "Ra" + getUniqueNumber();
+ // Skip if packet is not the right size
+ gen.addLoadFromMemory(Register.R0, gen.PACKET_SIZE_MEMORY_SLOT);
+ gen.addJumpIfR0NotEquals(mPacket.limit(), nextFilterLabel);
+ int filterLifetime = (int)(currentLifetime() / FRACTION_OF_LIFETIME_TO_FILTER);
+ // Skip filter if expired
+ gen.addLoadFromMemory(Register.R0, gen.FILTER_AGE_MEMORY_SLOT);
+ gen.addJumpIfR0GreaterThan(filterLifetime, nextFilterLabel);
+ for (int i = 0; i < mNonLifetimes.size(); i++) {
+ // Generate code to match the packet bytes
+ Pair<Integer, Integer> nonLifetime = mNonLifetimes.get(i);
+ gen.addLoadImmediate(Register.R0, nonLifetime.first);
+ gen.addJumpIfBytesNotEqual(Register.R0,
+ Arrays.copyOfRange(mPacket.array(), nonLifetime.first,
+ nonLifetime.first + nonLifetime.second),
+ nextFilterLabel);
+ // Generate code to test the lifetimes haven't gone down too far
+ if ((i + 1) < mNonLifetimes.size()) {
+ Pair<Integer, Integer> nextNonLifetime = mNonLifetimes.get(i + 1);
+ int offset = nonLifetime.first + nonLifetime.second;
+ int length = nextNonLifetime.first - offset;
+ switch (length) {
+ case 4: gen.addLoad32(Register.R0, offset); break;
+ case 2: gen.addLoad16(Register.R0, offset); break;
+ default: throw new IllegalStateException("bogus lifetime size " + length);
+ }
+ gen.addJumpIfR0LessThan(filterLifetime, nextFilterLabel);
+ }
+ }
+ gen.addJump(gen.DROP_LABEL);
+ gen.defineLabel(nextFilterLabel);
+ return filterLifetime;
+ }
+ }
+
+ // Maximum number of RAs to filter for.
+ private static final int MAX_RAS = 10;
+ private ArrayList<Ra> mRas = new ArrayList<Ra>();
+
+ // There is always some marginal benefit to updating the installed APF program when an RA is
+ // seen because we can extend the program's lifetime slightly, but there is some cost to
+ // updating the program, so don't bother unless the program is going to expire soon. This
+ // constant defines "soon" in seconds.
+ private static final long MAX_PROGRAM_LIFETIME_WORTH_REFRESHING = 30;
+ // We don't want to filter an RA for it's whole lifetime as it'll be expired by the time we ever
+ // see a refresh. Using half the lifetime might be a good idea except for the fact that
+ // packets may be dropped, so let's use 6.
+ private static final int FRACTION_OF_LIFETIME_TO_FILTER = 6;
+
+ // When did we last install a filter program? In seconds since Unix Epoch.
+ private long mLastTimeInstalledProgram;
+ // How long should the last installed filter program live for? In seconds.
+ private long mLastInstalledProgramMinLifetime;
+
+ private void installNewProgram() {
+ if (mRas.size() == 0) return;
+ final byte[] program;
+ long programMinLifetime = Long.MAX_VALUE;
+ try {
+ ApfGenerator gen = new ApfGenerator();
+ // This is guaranteed to return true because of the check in maybeInstall.
+ gen.setApfVersion(mNai.networkMisc.apfVersionSupported);
+ // Step 1: Determine how many RA filters we can fit in the program.
+ int ras = 0;
+ for (Ra ra : mRas) {
+ if (ra.isExpired()) continue;
+ ra.generateFilter(gen);
+ if (gen.programLengthOverEstimate() > mNai.networkMisc.maximumApfProgramSize) {
+ // We went too far. Use prior number of RAs in "ras".
+ break;
+ } else {
+ // Yay! this RA filter fits, increment "ras".
+ ras++;
+ }
+ }
+ // Step 2: Generate RA filters
+ gen = new ApfGenerator();
+ // This is guaranteed to return true because of the check in maybeInstall.
+ gen.setApfVersion(mNai.networkMisc.apfVersionSupported);
+ for (Ra ra : mRas) {
+ if (ras-- == 0) break;
+ if (ra.isExpired()) continue;
+ programMinLifetime = Math.min(programMinLifetime, ra.generateFilter(gen));
+ }
+ // Execution will reach the end of the program if no filters match, which will pass the
+ // packet to the AP.
+ program = gen.generate();
+ } catch (IllegalInstructionException e) {
+ Log.e(TAG, "Program failed to generate: ", e);
+ return;
+ }
+ mLastTimeInstalledProgram = curTime();
+ mLastInstalledProgramMinLifetime = programMinLifetime;
+ hexDump("Installing filter: ", program, program.length);
+ mConnectivityService.pushApfProgramToNetwork(mNai, program);
+ }
+
+ // Install a new filter program if the last installed one will die soon.
+ private void maybeInstallNewProgram() {
+ if (mRas.size() == 0) return;
+ // If the current program doesn't expire for a while, don't bother updating.
+ long expiry = mLastTimeInstalledProgram + mLastInstalledProgramMinLifetime;
+ if (expiry < curTime() + MAX_PROGRAM_LIFETIME_WORTH_REFRESHING) {
+ installNewProgram();
+ }
+ }
+
+ private void hexDump(String msg, byte[] packet, int length) {
+ log(msg + HexDump.toHexString(packet, 0, length));
+ }
+
+ private void processRa(byte[] packet, int length) {
+ hexDump("Read packet = ", packet, length);
+
+ // Have we seen this RA before?
+ for (int i = 0; i < mRas.size(); i++) {
+ Ra ra = mRas.get(i);
+ if (ra.matches(packet, length)) {
+ log("matched RA");
+ // Update lifetimes.
+ ra.mLastSeen = curTime();
+ ra.mMinLifetime = ra.minLifetime(packet, length);
+
+ // Keep mRas in LRU order so as to prioritize generating filters for recently seen
+ // RAs. LRU prioritizes this because RA filters are generated in order from mRas
+ // until the filter program exceeds the maximum filter program size allowed by the
+ // chipset, so RAs appearing earlier in mRas are more likely to make it into the
+ // filter program.
+ // TODO: consider sorting the RAs in order of increasing expiry time as well.
+ // Swap to front of array.
+ mRas.add(0, mRas.remove(i));
+
+ maybeInstallNewProgram();
+ return;
+ }
+ }
+ // Purge expired RAs.
+ for (int i = 0; i < mRas.size();) {
+ if (mRas.get(i).isExpired()) {
+ log("expired RA");
+ mRas.remove(i);
+ } else {
+ i++;
+ }
+ }
+ // TODO: figure out how to proceed when we've received more then MAX_RAS RAs.
+ if (mRas.size() >= MAX_RAS) return;
+ try {
+ log("adding RA");
+ mRas.add(new Ra(packet, length));
+ } catch (Exception e) {
+ Log.e(TAG, "Error parsing RA: " + e);
+ return;
+ }
+ installNewProgram();
+ }
+
+ /**
+ * Install an {@link ApfFilter} on {@code nai} if {@code nai} supports packet
+ * filtering using APF programs.
+ */
+ public static void maybeInstall(ConnectivityService connectivityService, NetworkAgentInfo nai) {
+ if (nai.networkMisc == null) return;
+ if (nai.networkMisc.apfVersionSupported == 0) return;
+ if (nai.networkMisc.maximumApfProgramSize < 200) {
+ Log.e(TAG, "Uselessly small APF size limit: " + nai.networkMisc.maximumApfProgramSize);
+ return;
+ }
+ // For now only support generating programs for Ethernet frames. If this restriction is
+ // lifted:
+ // 1. the program generator will need its offsets adjusted.
+ // 2. the packet filter attached to our packet socket will need its offset adjusted.
+ if (nai.networkMisc.apfPacketFormat != ARPHRD_ETHER) return;
+ if (!new ApfGenerator().setApfVersion(nai.networkMisc.apfVersionSupported)) {
+ Log.e(TAG, "Unsupported APF version: " + nai.networkMisc.apfVersionSupported);
+ return;
+ }
+ nai.apfFilter = new ApfFilter(connectivityService, nai);
+ }
+
+ public void shutdown() {
+ if (mReceiveThread != null) {
+ log("shuting down");
+ mReceiveThread.halt(); // Also closes socket.
+ mReceiveThread = null;
+ }
+ }
+}