| /* |
| * Copyright (C) 2017 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.tethering; |
| |
| import static android.net.NetworkStats.SET_DEFAULT; |
| import static android.net.NetworkStats.STATS_PER_UID; |
| import static android.net.NetworkStats.TAG_NONE; |
| import static android.net.NetworkStats.UID_ALL; |
| import static android.net.TrafficStats.UID_TETHERING; |
| import static android.provider.Settings.Global.TETHER_OFFLOAD_DISABLED; |
| |
| import android.content.ContentResolver; |
| import android.net.ITetheringStatsProvider; |
| import android.net.IpPrefix; |
| import android.net.LinkAddress; |
| import android.net.LinkProperties; |
| import android.net.NetworkStats; |
| import android.net.RouteInfo; |
| import android.net.netlink.ConntrackMessage; |
| import android.net.netlink.NetlinkConstants; |
| import android.net.netlink.NetlinkSocket; |
| import android.net.util.IpUtils; |
| import android.net.util.SharedLog; |
| import android.os.Handler; |
| import android.os.Looper; |
| import android.os.INetworkManagementService; |
| import android.os.RemoteException; |
| import android.os.SystemClock; |
| import android.provider.Settings; |
| import android.system.ErrnoException; |
| import android.system.OsConstants; |
| import android.text.TextUtils; |
| |
| import com.android.internal.util.IndentingPrintWriter; |
| import com.android.server.connectivity.tethering.OffloadHardwareInterface.ForwardedStats; |
| |
| import java.net.Inet4Address; |
| import java.net.Inet6Address; |
| import java.net.InetAddress; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * A class to encapsulate the business logic of programming the tethering |
| * hardware offload interface. |
| * |
| * @hide |
| */ |
| public class OffloadController { |
| private static final String TAG = OffloadController.class.getSimpleName(); |
| private static final boolean DBG = false; |
| private static final String ANYIP = "0.0.0.0"; |
| private static final ForwardedStats EMPTY_STATS = new ForwardedStats(); |
| |
| private static enum UpdateType { IF_NEEDED, FORCE }; |
| |
| private final Handler mHandler; |
| private final OffloadHardwareInterface mHwInterface; |
| private final ContentResolver mContentResolver; |
| private final INetworkManagementService mNms; |
| private final ITetheringStatsProvider mStatsProvider; |
| private final SharedLog mLog; |
| private final HashMap<String, LinkProperties> mDownstreams; |
| private boolean mConfigInitialized; |
| private boolean mControlInitialized; |
| private LinkProperties mUpstreamLinkProperties; |
| // The complete set of offload-exempt prefixes passed in via Tethering from |
| // all upstream and downstream sources. |
| private Set<IpPrefix> mExemptPrefixes; |
| // A strictly "smaller" set of prefixes, wherein offload-approved prefixes |
| // (e.g. downstream on-link prefixes) have been removed and replaced with |
| // prefixes representing only the locally-assigned IP addresses. |
| private Set<String> mLastLocalPrefixStrs; |
| |
| // Maps upstream interface names to offloaded traffic statistics. |
| // Always contains the latest value received from the hardware for each interface, regardless of |
| // whether offload is currently running on that interface. |
| private ConcurrentHashMap<String, ForwardedStats> mForwardedStats = |
| new ConcurrentHashMap<>(16, 0.75F, 1); |
| |
| // Maps upstream interface names to interface quotas. |
| // Always contains the latest value received from the framework for each interface, regardless |
| // of whether offload is currently running (or is even supported) on that interface. Only |
| // includes upstream interfaces that have a quota set. |
| private HashMap<String, Long> mInterfaceQuotas = new HashMap<>(); |
| |
| private int mNatUpdateCallbacksReceived; |
| private int mNatUpdateNetlinkErrors; |
| |
| public OffloadController(Handler h, OffloadHardwareInterface hwi, |
| ContentResolver contentResolver, INetworkManagementService nms, SharedLog log) { |
| mHandler = h; |
| mHwInterface = hwi; |
| mContentResolver = contentResolver; |
| mNms = nms; |
| mStatsProvider = new OffloadTetheringStatsProvider(); |
| mLog = log.forSubComponent(TAG); |
| mDownstreams = new HashMap<>(); |
| mExemptPrefixes = new HashSet<>(); |
| mLastLocalPrefixStrs = new HashSet<>(); |
| |
| try { |
| mNms.registerTetheringStatsProvider(mStatsProvider, getClass().getSimpleName()); |
| } catch (RemoteException e) { |
| mLog.e("Cannot register offload stats provider: " + e); |
| } |
| } |
| |
| public boolean start() { |
| if (started()) return true; |
| |
| if (isOffloadDisabled()) { |
| mLog.i("tethering offload disabled"); |
| return false; |
| } |
| |
| if (!mConfigInitialized) { |
| mConfigInitialized = mHwInterface.initOffloadConfig(); |
| if (!mConfigInitialized) { |
| mLog.i("tethering offload config not supported"); |
| stop(); |
| return false; |
| } |
| } |
| |
| mControlInitialized = mHwInterface.initOffloadControl( |
| // OffloadHardwareInterface guarantees that these callback |
| // methods are called on the handler passed to it, which is the |
| // same as mHandler, as coordinated by the setup in Tethering. |
| new OffloadHardwareInterface.ControlCallback() { |
| @Override |
| public void onStarted() { |
| if (!started()) return; |
| mLog.log("onStarted"); |
| } |
| |
| @Override |
| public void onStoppedError() { |
| if (!started()) return; |
| mLog.log("onStoppedError"); |
| } |
| |
| @Override |
| public void onStoppedUnsupported() { |
| if (!started()) return; |
| mLog.log("onStoppedUnsupported"); |
| // Poll for statistics and trigger a sweep of tethering |
| // stats by observers. This might not succeed, but it's |
| // worth trying anyway. We need to do this because from |
| // this point on we continue with software forwarding, |
| // and we need to synchronize stats and limits between |
| // software and hardware forwarding. |
| updateStatsForAllUpstreams(); |
| forceTetherStatsPoll(); |
| } |
| |
| @Override |
| public void onSupportAvailable() { |
| if (!started()) return; |
| mLog.log("onSupportAvailable"); |
| |
| // [1] Poll for statistics and trigger a sweep of stats |
| // by observers. We need to do this to ensure that any |
| // limits set take into account any software tethering |
| // traffic that has been happening in the meantime. |
| updateStatsForAllUpstreams(); |
| forceTetherStatsPoll(); |
| // [2] (Re)Push all state. |
| computeAndPushLocalPrefixes(UpdateType.FORCE); |
| pushAllDownstreamState(); |
| pushUpstreamParameters(null); |
| } |
| |
| @Override |
| public void onStoppedLimitReached() { |
| if (!started()) return; |
| mLog.log("onStoppedLimitReached"); |
| |
| // We cannot reliably determine on which interface the limit was reached, |
| // because the HAL interface does not specify it. We cannot just use the |
| // current upstream, because that might have changed since the time that |
| // the HAL queued the callback. |
| // TODO: rev the HAL so that it provides an interface name. |
| |
| // Fetch current stats, so that when our notification reaches |
| // NetworkStatsService and triggers a poll, we will respond with |
| // current data (which will be above the limit that was reached). |
| // Note that if we just changed upstream, this is unnecessary but harmless. |
| // The stats for the previous upstream were already updated on this thread |
| // just after the upstream was changed, so they are also up-to-date. |
| updateStatsForCurrentUpstream(); |
| forceTetherStatsPoll(); |
| } |
| |
| @Override |
| public void onNatTimeoutUpdate(int proto, |
| String srcAddr, int srcPort, |
| String dstAddr, int dstPort) { |
| if (!started()) return; |
| updateNatTimeout(proto, srcAddr, srcPort, dstAddr, dstPort); |
| } |
| }); |
| |
| final boolean isStarted = started(); |
| if (!isStarted) { |
| mLog.i("tethering offload control not supported"); |
| stop(); |
| } else { |
| mLog.log("tethering offload started"); |
| mNatUpdateCallbacksReceived = 0; |
| mNatUpdateNetlinkErrors = 0; |
| } |
| return isStarted; |
| } |
| |
| public void stop() { |
| // Completely stops tethering offload. After this method is called, it is no longer safe to |
| // call any HAL method, no callbacks from the hardware will be delivered, and any in-flight |
| // callbacks must be ignored. Offload may be started again by calling start(). |
| final boolean wasStarted = started(); |
| updateStatsForCurrentUpstream(); |
| mUpstreamLinkProperties = null; |
| mHwInterface.stopOffloadControl(); |
| mControlInitialized = false; |
| mConfigInitialized = false; |
| if (wasStarted) mLog.log("tethering offload stopped"); |
| } |
| |
| private boolean started() { |
| return mConfigInitialized && mControlInitialized; |
| } |
| |
| private class OffloadTetheringStatsProvider extends ITetheringStatsProvider.Stub { |
| @Override |
| public NetworkStats getTetherStats(int how) { |
| // getTetherStats() is the only function in OffloadController that can be called from |
| // a different thread. Do not attempt to update stats by querying the offload HAL |
| // synchronously from a different thread than our Handler thread. http://b/64771555. |
| Runnable updateStats = () -> { updateStatsForCurrentUpstream(); }; |
| if (Looper.myLooper() == mHandler.getLooper()) { |
| updateStats.run(); |
| } else { |
| mHandler.post(updateStats); |
| } |
| |
| NetworkStats stats = new NetworkStats(SystemClock.elapsedRealtime(), 0); |
| NetworkStats.Entry entry = new NetworkStats.Entry(); |
| entry.set = SET_DEFAULT; |
| entry.tag = TAG_NONE; |
| entry.uid = (how == STATS_PER_UID) ? UID_TETHERING : UID_ALL; |
| |
| for (Map.Entry<String, ForwardedStats> kv : mForwardedStats.entrySet()) { |
| ForwardedStats value = kv.getValue(); |
| entry.iface = kv.getKey(); |
| entry.rxBytes = value.rxBytes; |
| entry.txBytes = value.txBytes; |
| stats.addValues(entry); |
| } |
| |
| return stats; |
| } |
| |
| @Override |
| public void setInterfaceQuota(String iface, long quotaBytes) { |
| mHandler.post(() -> { |
| if (quotaBytes == ITetheringStatsProvider.QUOTA_UNLIMITED) { |
| mInterfaceQuotas.remove(iface); |
| } else { |
| mInterfaceQuotas.put(iface, quotaBytes); |
| } |
| maybeUpdateDataLimit(iface); |
| }); |
| } |
| } |
| |
| private String currentUpstreamInterface() { |
| return (mUpstreamLinkProperties != null) |
| ? mUpstreamLinkProperties.getInterfaceName() : null; |
| } |
| |
| private void maybeUpdateStats(String iface) { |
| if (TextUtils.isEmpty(iface)) { |
| return; |
| } |
| |
| // Always called on the handler thread. |
| // |
| // Use get()/put() instead of updating ForwardedStats in place because we can be called |
| // concurrently with getTetherStats. In combination with the guarantees provided by |
| // ConcurrentHashMap, this ensures that getTetherStats always gets the most recent copy of |
| // the stats for each interface, and does not observe partial writes where rxBytes is |
| // updated and txBytes is not. |
| ForwardedStats diff = mHwInterface.getForwardedStats(iface); |
| ForwardedStats base = mForwardedStats.get(iface); |
| if (base != null) { |
| diff.add(base); |
| } |
| mForwardedStats.put(iface, diff); |
| // diff is a new object, just created by getForwardedStats(). Therefore, anyone reading from |
| // mForwardedStats (i.e., any caller of getTetherStats) will see the new stats immediately. |
| } |
| |
| private boolean maybeUpdateDataLimit(String iface) { |
| // setDataLimit may only be called while offload is occurring on this upstream. |
| if (!started() || !TextUtils.equals(iface, currentUpstreamInterface())) { |
| return true; |
| } |
| |
| Long limit = mInterfaceQuotas.get(iface); |
| if (limit == null) { |
| limit = Long.MAX_VALUE; |
| } |
| |
| return mHwInterface.setDataLimit(iface, limit); |
| } |
| |
| private void updateStatsForCurrentUpstream() { |
| maybeUpdateStats(currentUpstreamInterface()); |
| } |
| |
| private void updateStatsForAllUpstreams() { |
| // In practice, there should only ever be a single digit number of |
| // upstream interfaces over the lifetime of an active tethering session. |
| // Roughly speaking, imagine a very ambitious one or two of each of the |
| // following interface types: [ "rmnet_data", "wlan", "eth", "rndis" ]. |
| for (Map.Entry<String, ForwardedStats> kv : mForwardedStats.entrySet()) { |
| maybeUpdateStats(kv.getKey()); |
| } |
| } |
| |
| private void forceTetherStatsPoll() { |
| try { |
| mNms.tetherLimitReached(mStatsProvider); |
| } catch (RemoteException e) { |
| mLog.e("Cannot report data limit reached: " + e); |
| } |
| } |
| |
| public void setUpstreamLinkProperties(LinkProperties lp) { |
| if (!started() || Objects.equals(mUpstreamLinkProperties, lp)) return; |
| |
| final String prevUpstream = currentUpstreamInterface(); |
| |
| mUpstreamLinkProperties = (lp != null) ? new LinkProperties(lp) : null; |
| // Make sure we record this interface in the ForwardedStats map. |
| final String iface = currentUpstreamInterface(); |
| if (!TextUtils.isEmpty(iface)) mForwardedStats.putIfAbsent(iface, EMPTY_STATS); |
| |
| // TODO: examine return code and decide what to do if programming |
| // upstream parameters fails (probably just wait for a subsequent |
| // onOffloadEvent() callback to tell us offload is available again and |
| // then reapply all state). |
| computeAndPushLocalPrefixes(UpdateType.IF_NEEDED); |
| pushUpstreamParameters(prevUpstream); |
| } |
| |
| public void setLocalPrefixes(Set<IpPrefix> localPrefixes) { |
| mExemptPrefixes = localPrefixes; |
| |
| if (!started()) return; |
| computeAndPushLocalPrefixes(UpdateType.IF_NEEDED); |
| } |
| |
| public void notifyDownstreamLinkProperties(LinkProperties lp) { |
| final String ifname = lp.getInterfaceName(); |
| final LinkProperties oldLp = mDownstreams.put(ifname, new LinkProperties(lp)); |
| if (Objects.equals(oldLp, lp)) return; |
| |
| if (!started()) return; |
| pushDownstreamState(oldLp, lp); |
| } |
| |
| private void pushDownstreamState(LinkProperties oldLp, LinkProperties newLp) { |
| final String ifname = newLp.getInterfaceName(); |
| final List<RouteInfo> oldRoutes = |
| (oldLp != null) ? oldLp.getRoutes() : Collections.EMPTY_LIST; |
| final List<RouteInfo> newRoutes = newLp.getRoutes(); |
| |
| // For each old route, if not in new routes: remove. |
| for (RouteInfo ri : oldRoutes) { |
| if (shouldIgnoreDownstreamRoute(ri)) continue; |
| if (!newRoutes.contains(ri)) { |
| mHwInterface.removeDownstreamPrefix(ifname, ri.getDestination().toString()); |
| } |
| } |
| |
| // For each new route, if not in old routes: add. |
| for (RouteInfo ri : newRoutes) { |
| if (shouldIgnoreDownstreamRoute(ri)) continue; |
| if (!oldRoutes.contains(ri)) { |
| mHwInterface.addDownstreamPrefix(ifname, ri.getDestination().toString()); |
| } |
| } |
| } |
| |
| private void pushAllDownstreamState() { |
| for (LinkProperties lp : mDownstreams.values()) { |
| pushDownstreamState(null, lp); |
| } |
| } |
| |
| public void removeDownstreamInterface(String ifname) { |
| final LinkProperties lp = mDownstreams.remove(ifname); |
| if (lp == null) return; |
| |
| if (!started()) return; |
| |
| for (RouteInfo route : lp.getRoutes()) { |
| if (shouldIgnoreDownstreamRoute(route)) continue; |
| mHwInterface.removeDownstreamPrefix(ifname, route.getDestination().toString()); |
| } |
| } |
| |
| private boolean isOffloadDisabled() { |
| final int defaultDisposition = mHwInterface.getDefaultTetherOffloadDisabled(); |
| return (Settings.Global.getInt( |
| mContentResolver, TETHER_OFFLOAD_DISABLED, defaultDisposition) != 0); |
| } |
| |
| private boolean pushUpstreamParameters(String prevUpstream) { |
| final String iface = currentUpstreamInterface(); |
| |
| if (TextUtils.isEmpty(iface)) { |
| final boolean rval = mHwInterface.setUpstreamParameters("", ANYIP, ANYIP, null); |
| // Update stats after we've told the hardware to stop forwarding so |
| // we don't miss packets. |
| maybeUpdateStats(prevUpstream); |
| return rval; |
| } |
| |
| // A stacked interface cannot be an upstream for hardware offload. |
| // Consequently, we examine only the primary interface name, look at |
| // getAddresses() rather than getAllAddresses(), and check getRoutes() |
| // rather than getAllRoutes(). |
| final ArrayList<String> v6gateways = new ArrayList<>(); |
| String v4addr = null; |
| String v4gateway = null; |
| |
| for (InetAddress ip : mUpstreamLinkProperties.getAddresses()) { |
| if (ip instanceof Inet4Address) { |
| v4addr = ip.getHostAddress(); |
| break; |
| } |
| } |
| |
| // Find the gateway addresses of all default routes of either address family. |
| for (RouteInfo ri : mUpstreamLinkProperties.getRoutes()) { |
| if (!ri.hasGateway()) continue; |
| |
| final String gateway = ri.getGateway().getHostAddress(); |
| if (ri.isIPv4Default()) { |
| v4gateway = gateway; |
| } else if (ri.isIPv6Default()) { |
| v6gateways.add(gateway); |
| } |
| } |
| |
| boolean success = mHwInterface.setUpstreamParameters( |
| iface, v4addr, v4gateway, (v6gateways.isEmpty() ? null : v6gateways)); |
| |
| if (!success) { |
| return success; |
| } |
| |
| // Update stats after we've told the hardware to change routing so we don't miss packets. |
| maybeUpdateStats(prevUpstream); |
| |
| // Data limits can only be set once offload is running on the upstream. |
| success = maybeUpdateDataLimit(iface); |
| if (!success) { |
| // If we failed to set a data limit, don't use this upstream, because we don't want to |
| // blow through the data limit that we were told to apply. |
| mLog.log("Setting data limit for " + iface + " failed, disabling offload."); |
| stop(); |
| } |
| |
| return success; |
| } |
| |
| private boolean computeAndPushLocalPrefixes(UpdateType how) { |
| final boolean force = (how == UpdateType.FORCE); |
| final Set<String> localPrefixStrs = computeLocalPrefixStrings( |
| mExemptPrefixes, mUpstreamLinkProperties); |
| if (!force && mLastLocalPrefixStrs.equals(localPrefixStrs)) return true; |
| |
| mLastLocalPrefixStrs = localPrefixStrs; |
| return mHwInterface.setLocalPrefixes(new ArrayList<>(localPrefixStrs)); |
| } |
| |
| // TODO: Factor in downstream LinkProperties once that information is available. |
| private static Set<String> computeLocalPrefixStrings( |
| Set<IpPrefix> localPrefixes, LinkProperties upstreamLinkProperties) { |
| // Create an editable copy. |
| final Set<IpPrefix> prefixSet = new HashSet<>(localPrefixes); |
| |
| // TODO: If a downstream interface (not currently passed in) is reusing |
| // the /64 of the upstream (64share) then: |
| // |
| // [a] remove that /64 from the local prefixes |
| // [b] add in /128s for IP addresses on the downstream interface |
| // [c] add in /128s for IP addresses on the upstream interface |
| // |
| // Until downstream information is available here, simply add /128s from |
| // the upstream network; they'll just be redundant with their /64. |
| if (upstreamLinkProperties != null) { |
| for (LinkAddress linkAddr : upstreamLinkProperties.getLinkAddresses()) { |
| if (!linkAddr.isGlobalPreferred()) continue; |
| final InetAddress ip = linkAddr.getAddress(); |
| if (!(ip instanceof Inet6Address)) continue; |
| prefixSet.add(new IpPrefix(ip, 128)); |
| } |
| } |
| |
| final HashSet<String> localPrefixStrs = new HashSet<>(); |
| for (IpPrefix pfx : prefixSet) localPrefixStrs.add(pfx.toString()); |
| return localPrefixStrs; |
| } |
| |
| private static boolean shouldIgnoreDownstreamRoute(RouteInfo route) { |
| // Ignore any link-local routes. |
| if (!route.getDestinationLinkAddress().isGlobalPreferred()) return true; |
| |
| return false; |
| } |
| |
| public void dump(IndentingPrintWriter pw) { |
| if (isOffloadDisabled()) { |
| pw.println("Offload disabled"); |
| return; |
| } |
| final boolean isStarted = started(); |
| pw.println("Offload HALs " + (isStarted ? "started" : "not started")); |
| LinkProperties lp = mUpstreamLinkProperties; |
| String upstream = (lp != null) ? lp.getInterfaceName() : null; |
| pw.println("Current upstream: " + upstream); |
| pw.println("Exempt prefixes: " + mLastLocalPrefixStrs); |
| pw.println("NAT timeout update callbacks received during the " |
| + (isStarted ? "current" : "last") |
| + " offload session: " |
| + mNatUpdateCallbacksReceived); |
| pw.println("NAT timeout update netlink errors during the " |
| + (isStarted ? "current" : "last") |
| + " offload session: " |
| + mNatUpdateNetlinkErrors); |
| } |
| |
| private void updateNatTimeout( |
| int proto, String srcAddr, int srcPort, String dstAddr, int dstPort) { |
| final String protoName = protoNameFor(proto); |
| if (protoName == null) { |
| mLog.e("Unknown NAT update callback protocol: " + proto); |
| return; |
| } |
| |
| final Inet4Address src = parseIPv4Address(srcAddr); |
| if (src == null) { |
| mLog.e("Failed to parse IPv4 address: " + srcAddr); |
| return; |
| } |
| |
| if (!IpUtils.isValidUdpOrTcpPort(srcPort)) { |
| mLog.e("Invalid src port: " + srcPort); |
| return; |
| } |
| |
| final Inet4Address dst = parseIPv4Address(dstAddr); |
| if (dst == null) { |
| mLog.e("Failed to parse IPv4 address: " + dstAddr); |
| return; |
| } |
| |
| if (!IpUtils.isValidUdpOrTcpPort(dstPort)) { |
| mLog.e("Invalid dst port: " + dstPort); |
| return; |
| } |
| |
| mNatUpdateCallbacksReceived++; |
| final String natDescription = String.format("%s (%s, %s) -> (%s, %s)", |
| protoName, srcAddr, srcPort, dstAddr, dstPort); |
| if (DBG) { |
| mLog.log("NAT timeout update: " + natDescription); |
| } |
| |
| final int timeoutSec = connectionTimeoutUpdateSecondsFor(proto); |
| final byte[] msg = ConntrackMessage.newIPv4TimeoutUpdateRequest( |
| proto, src, srcPort, dst, dstPort, timeoutSec); |
| |
| try { |
| NetlinkSocket.sendOneShotKernelMessage(OsConstants.NETLINK_NETFILTER, msg); |
| } catch (ErrnoException e) { |
| mNatUpdateNetlinkErrors++; |
| mLog.e("Error updating NAT conntrack entry >" + natDescription + "<: " + e |
| + ", msg: " + NetlinkConstants.hexify(msg)); |
| mLog.log("NAT timeout update callbacks received: " + mNatUpdateCallbacksReceived); |
| mLog.log("NAT timeout update netlink errors: " + mNatUpdateNetlinkErrors); |
| } |
| } |
| |
| private static Inet4Address parseIPv4Address(String addrString) { |
| try { |
| final InetAddress ip = InetAddress.parseNumericAddress(addrString); |
| // TODO: Consider other sanitization steps here, including perhaps: |
| // not eql to 0.0.0.0 |
| // not within 169.254.0.0/16 |
| // not within ::ffff:0.0.0.0/96 |
| // not within ::/96 |
| // et cetera. |
| if (ip instanceof Inet4Address) { |
| return (Inet4Address) ip; |
| } |
| } catch (IllegalArgumentException iae) {} |
| return null; |
| } |
| |
| private static String protoNameFor(int proto) { |
| // OsConstants values are not constant expressions; no switch statement. |
| if (proto == OsConstants.IPPROTO_UDP) { |
| return "UDP"; |
| } else if (proto == OsConstants.IPPROTO_TCP) { |
| return "TCP"; |
| } |
| return null; |
| } |
| |
| private static int connectionTimeoutUpdateSecondsFor(int proto) { |
| // TODO: Replace this with more thoughtful work, perhaps reading from |
| // and maybe writing to any required |
| // |
| // /proc/sys/net/netfilter/nf_conntrack_tcp_timeout_* |
| // /proc/sys/net/netfilter/nf_conntrack_udp_timeout{,_stream} |
| // |
| // entries. TBD. |
| if (proto == OsConstants.IPPROTO_TCP) { |
| // Cf. /proc/sys/net/netfilter/nf_conntrack_tcp_timeout_established |
| return 432000; |
| } else { |
| // Cf. /proc/sys/net/netfilter/nf_conntrack_udp_timeout_stream |
| return 180; |
| } |
| } |
| } |