diff options
Diffstat (limited to 'packages/Tethering/src/android/net/ip/IpServer.java')
| -rw-r--r-- | packages/Tethering/src/android/net/ip/IpServer.java | 1422 |
1 files changed, 0 insertions, 1422 deletions
diff --git a/packages/Tethering/src/android/net/ip/IpServer.java b/packages/Tethering/src/android/net/ip/IpServer.java deleted file mode 100644 index 52d59fcdc19b..000000000000 --- a/packages/Tethering/src/android/net/ip/IpServer.java +++ /dev/null @@ -1,1422 +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.RouteInfo.RTN_UNICAST; -import static android.net.TetheringManager.TetheringRequest.checkStaticAddressConfiguration; -import static android.net.dhcp.IDhcpServer.STATUS_SUCCESS; -import static android.net.util.NetworkConstants.RFC7421_PREFIX_LENGTH; -import static android.net.util.NetworkConstants.asByte; -import static android.net.util.PrefixUtils.asIpPrefix; -import static android.net.util.TetheringMessageBase.BASE_IPSERVER; -import static android.system.OsConstants.RT_SCOPE_UNIVERSE; - -import static com.android.net.module.util.Inet4AddressUtils.intToInet4AddressHTH; - -import android.net.INetd; -import android.net.INetworkStackStatusCallback; -import android.net.IpPrefix; -import android.net.LinkAddress; -import android.net.LinkProperties; -import android.net.MacAddress; -import android.net.RouteInfo; -import android.net.TetheredClient; -import android.net.TetheringManager; -import android.net.TetheringRequestParcel; -import android.net.dhcp.DhcpLeaseParcelable; -import android.net.dhcp.DhcpServerCallbacks; -import android.net.dhcp.DhcpServingParamsParcel; -import android.net.dhcp.DhcpServingParamsParcelExt; -import android.net.dhcp.IDhcpEventCallbacks; -import android.net.dhcp.IDhcpServer; -import android.net.ip.IpNeighborMonitor.NeighborEvent; -import android.net.ip.RouterAdvertisementDaemon.RaParams; -import android.net.shared.NetdUtils; -import android.net.shared.RouteUtils; -import android.net.util.InterfaceParams; -import android.net.util.InterfaceSet; -import android.net.util.PrefixUtils; -import android.net.util.SharedLog; -import android.os.Build; -import android.os.Handler; -import android.os.Looper; -import android.os.Message; -import android.os.RemoteException; -import android.os.ServiceSpecificException; -import android.util.Log; -import android.util.SparseArray; - -import androidx.annotation.NonNull; -import androidx.annotation.Nullable; - -import com.android.internal.util.MessageUtils; -import com.android.internal.util.State; -import com.android.internal.util.StateMachine; -import com.android.networkstack.tethering.BpfCoordinator; -import com.android.networkstack.tethering.BpfCoordinator.Ipv6ForwardingRule; -import com.android.networkstack.tethering.PrivateAddressCoordinator; - -import java.io.IOException; -import java.net.Inet4Address; -import java.net.Inet6Address; -import java.net.NetworkInterface; -import java.net.UnknownHostException; -import java.util.ArrayList; -import java.util.Arrays; -import java.util.Collections; -import java.util.HashSet; -import java.util.List; -import java.util.Objects; -import java.util.Random; -import java.util.Set; - -/** - * Provides the interface to IP-layer serving functionality for a given network - * interface, e.g. for tethering or "local-only hotspot" mode. - * - * @hide - */ -public class IpServer extends StateMachine { - public static final int STATE_UNAVAILABLE = 0; - public static final int STATE_AVAILABLE = 1; - public static final int STATE_TETHERED = 2; - public static final int STATE_LOCAL_ONLY = 3; - - /** Get string name of |state|.*/ - public static String getStateString(int state) { - switch (state) { - case STATE_UNAVAILABLE: return "UNAVAILABLE"; - case STATE_AVAILABLE: return "AVAILABLE"; - case STATE_TETHERED: return "TETHERED"; - case STATE_LOCAL_ONLY: return "LOCAL_ONLY"; - } - return "UNKNOWN: " + state; - } - - private static final byte DOUG_ADAMS = (byte) 42; - - // TODO: have PanService use some visible version of this constant - private static final String BLUETOOTH_IFACE_ADDR = "192.168.44.1/24"; - - // TODO: have this configurable - private static final int DHCP_LEASE_TIME_SECS = 3600; - - private static final MacAddress NULL_MAC_ADDRESS = MacAddress.fromString("00:00:00:00:00:00"); - - private static final String TAG = "IpServer"; - private static final boolean DBG = false; - private static final boolean VDBG = false; - private static final Class[] sMessageClasses = { - IpServer.class - }; - private static final SparseArray<String> sMagicDecoderRing = - MessageUtils.findMessageNames(sMessageClasses); - - /** IpServer callback. */ - public static class Callback { - /** - * Notify that |who| has changed its tethering state. - * - * @param who the calling instance of IpServer - * @param state one of STATE_* - * @param lastError one of TetheringManager.TETHER_ERROR_* - */ - public void updateInterfaceState(IpServer who, int state, int lastError) { } - - /** - * Notify that |who| has new LinkProperties. - * - * @param who the calling instance of IpServer - * @param newLp the new LinkProperties to report - */ - public void updateLinkProperties(IpServer who, LinkProperties newLp) { } - - /** - * Notify that the DHCP leases changed in one of the IpServers. - */ - public void dhcpLeasesChanged() { } - - /** - * Request Tethering change. - * - * @param tetheringType the downstream type of this IpServer. - * @param enabled enable or disable tethering. - */ - public void requestEnableTethering(int tetheringType, boolean enabled) { } - } - - /** Capture IpServer dependencies, for injection. */ - public abstract static class Dependencies { - /** - * Create a DadProxy instance to be used by IpServer. - * To support multiple tethered interfaces concurrently DAD Proxy - * needs to be supported per IpServer instead of per upstream. - */ - public DadProxy getDadProxy(Handler handler, InterfaceParams ifParams) { - return new DadProxy(handler, ifParams); - } - - /** Create an IpNeighborMonitor to be used by this IpServer */ - public IpNeighborMonitor getIpNeighborMonitor(Handler handler, SharedLog log, - IpNeighborMonitor.NeighborEventConsumer consumer) { - return new IpNeighborMonitor(handler, log, consumer); - } - - /** Create a RouterAdvertisementDaemon instance to be used by IpServer.*/ - public RouterAdvertisementDaemon getRouterAdvertisementDaemon(InterfaceParams ifParams) { - return new RouterAdvertisementDaemon(ifParams); - } - - /** Get |ifName|'s interface information.*/ - public InterfaceParams getInterfaceParams(String ifName) { - return InterfaceParams.getByName(ifName); - } - - /** Get |ifName|'s interface index. */ - public int getIfindex(String ifName) { - try { - return NetworkInterface.getByName(ifName).getIndex(); - } catch (IOException | NullPointerException e) { - Log.e(TAG, "Can't determine interface index for interface " + ifName); - return 0; - } - } - - /** Create a DhcpServer instance to be used by IpServer. */ - public abstract void makeDhcpServer(String ifName, DhcpServingParamsParcel params, - DhcpServerCallbacks cb); - } - - // request from the user that it wants to tether - public static final int CMD_TETHER_REQUESTED = BASE_IPSERVER + 1; - // request from the user that it wants to untether - public static final int CMD_TETHER_UNREQUESTED = BASE_IPSERVER + 2; - // notification that this interface is down - public static final int CMD_INTERFACE_DOWN = BASE_IPSERVER + 3; - // notification from the {@link Tethering.TetherMainSM} that it had trouble enabling IP - // Forwarding - public static final int CMD_IP_FORWARDING_ENABLE_ERROR = BASE_IPSERVER + 4; - // notification from the {@link Tethering.TetherMainSM} SM that it had trouble disabling IP - // Forwarding - public static final int CMD_IP_FORWARDING_DISABLE_ERROR = BASE_IPSERVER + 5; - // notification from the {@link Tethering.TetherMainSM} SM that it had trouble starting - // tethering - public static final int CMD_START_TETHERING_ERROR = BASE_IPSERVER + 6; - // notification from the {@link Tethering.TetherMainSM} that it had trouble stopping tethering - public static final int CMD_STOP_TETHERING_ERROR = BASE_IPSERVER + 7; - // notification from the {@link Tethering.TetherMainSM} that it had trouble setting the DNS - // forwarders - public static final int CMD_SET_DNS_FORWARDERS_ERROR = BASE_IPSERVER + 8; - // the upstream connection has changed - public static final int CMD_TETHER_CONNECTION_CHANGED = BASE_IPSERVER + 9; - // new IPv6 tethering parameters need to be processed - public static final int CMD_IPV6_TETHER_UPDATE = BASE_IPSERVER + 10; - // new neighbor cache entry on our interface - public static final int CMD_NEIGHBOR_EVENT = BASE_IPSERVER + 11; - // request from DHCP server that it wants to have a new prefix - public static final int CMD_NEW_PREFIX_REQUEST = BASE_IPSERVER + 12; - // request from PrivateAddressCoordinator to restart tethering. - public static final int CMD_NOTIFY_PREFIX_CONFLICT = BASE_IPSERVER + 13; - - private final State mInitialState; - private final State mLocalHotspotState; - private final State mTetheredState; - private final State mUnavailableState; - private final State mWaitingForRestartState; - - private final SharedLog mLog; - private final INetd mNetd; - @NonNull - private final BpfCoordinator mBpfCoordinator; - private final Callback mCallback; - private final InterfaceController mInterfaceCtrl; - private final PrivateAddressCoordinator mPrivateAddressCoordinator; - - private final String mIfaceName; - private final int mInterfaceType; - private final LinkProperties mLinkProperties; - private final boolean mUsingLegacyDhcp; - private final boolean mUsingBpfOffload; - - private final Dependencies mDeps; - - private int mLastError; - private int mServingMode; - private InterfaceSet mUpstreamIfaceSet; // may change over time - private InterfaceParams mInterfaceParams; - // TODO: De-duplicate this with mLinkProperties above. Currently, these link - // properties are those selected by the IPv6TetheringCoordinator and relayed - // to us. By comparison, mLinkProperties contains the addresses and directly - // connected routes that have been formed from these properties iff. we have - // succeeded in configuring them and are able to announce them within Router - // Advertisements (otherwise, we do not add them to mLinkProperties at all). - private LinkProperties mLastIPv6LinkProperties; - private RouterAdvertisementDaemon mRaDaemon; - private DadProxy mDadProxy; - - // To be accessed only on the handler thread - private int mDhcpServerStartIndex = 0; - private IDhcpServer mDhcpServer; - private RaParams mLastRaParams; - - private LinkAddress mStaticIpv4ServerAddr; - private LinkAddress mStaticIpv4ClientAddr; - - @NonNull - private List<TetheredClient> mDhcpLeases = Collections.emptyList(); - - private int mLastIPv6UpstreamIfindex = 0; - - private class MyNeighborEventConsumer implements IpNeighborMonitor.NeighborEventConsumer { - public void accept(NeighborEvent e) { - sendMessage(CMD_NEIGHBOR_EVENT, e); - } - } - - private final IpNeighborMonitor mIpNeighborMonitor; - - private LinkAddress mIpv4Address; - - // TODO: Add a dependency object to pass the data members or variables from the tethering - // object. It helps to reduce the arguments of the constructor. - public IpServer( - String ifaceName, Looper looper, int interfaceType, SharedLog log, - INetd netd, @NonNull BpfCoordinator coordinator, Callback callback, - boolean usingLegacyDhcp, boolean usingBpfOffload, - PrivateAddressCoordinator addressCoordinator, Dependencies deps) { - super(ifaceName, looper); - mLog = log.forSubComponent(ifaceName); - mNetd = netd; - mBpfCoordinator = coordinator; - mCallback = callback; - mInterfaceCtrl = new InterfaceController(ifaceName, mNetd, mLog); - mIfaceName = ifaceName; - mInterfaceType = interfaceType; - mLinkProperties = new LinkProperties(); - mUsingLegacyDhcp = usingLegacyDhcp; - mUsingBpfOffload = usingBpfOffload; - mPrivateAddressCoordinator = addressCoordinator; - mDeps = deps; - resetLinkProperties(); - mLastError = TetheringManager.TETHER_ERROR_NO_ERROR; - mServingMode = STATE_AVAILABLE; - - mIpNeighborMonitor = mDeps.getIpNeighborMonitor(getHandler(), mLog, - new MyNeighborEventConsumer()); - - // IP neighbor monitor monitors the neighbor events for adding/removing offload - // forwarding rules per client. If BPF offload is not supported, don't start listening - // for neighbor events. See updateIpv6ForwardingRules, addIpv6ForwardingRule, - // removeIpv6ForwardingRule. - if (mUsingBpfOffload && !mIpNeighborMonitor.start()) { - mLog.e("Failed to create IpNeighborMonitor on " + mIfaceName); - } - - mInitialState = new InitialState(); - mLocalHotspotState = new LocalHotspotState(); - mTetheredState = new TetheredState(); - mUnavailableState = new UnavailableState(); - mWaitingForRestartState = new WaitingForRestartState(); - addState(mInitialState); - addState(mLocalHotspotState); - addState(mTetheredState); - addState(mWaitingForRestartState, mTetheredState); - addState(mUnavailableState); - - setInitialState(mInitialState); - } - - /** Interface name which IpServer served.*/ - public String interfaceName() { - return mIfaceName; - } - - /** - * Tethering downstream type. It would be one of TetheringManager#TETHERING_*. - */ - public int interfaceType() { - return mInterfaceType; - } - - /** Last error from this IpServer. */ - public int lastError() { - return mLastError; - } - - /** Serving mode is the current state of IpServer state machine. */ - public int servingMode() { - return mServingMode; - } - - /** The properties of the network link which IpServer is serving. */ - public LinkProperties linkProperties() { - return new LinkProperties(mLinkProperties); - } - - /** The address which IpServer is using. */ - public LinkAddress getAddress() { - return mIpv4Address; - } - - /** - * Get the latest list of DHCP leases that was reported. Must be called on the IpServer looper - * thread. - */ - public List<TetheredClient> getAllLeases() { - return Collections.unmodifiableList(mDhcpLeases); - } - - /** Stop this IpServer. After this is called this IpServer should not be used any more. */ - public void stop() { - sendMessage(CMD_INTERFACE_DOWN); - } - - /** - * Tethering is canceled. IpServer state machine will be available and wait for - * next tethering request. - */ - public void unwanted() { - sendMessage(CMD_TETHER_UNREQUESTED); - } - - /** Internals. */ - - private boolean startIPv4() { - return configureIPv4(true); - } - - /** - * Convenience wrapper around INetworkStackStatusCallback to run callbacks on the IpServer - * handler. - * - * <p>Different instances of this class can be created for each call to IDhcpServer methods, - * with different implementations of the callback, to differentiate handling of success/error in - * each call. - */ - private abstract class OnHandlerStatusCallback extends INetworkStackStatusCallback.Stub { - @Override - public void onStatusAvailable(int statusCode) { - getHandler().post(() -> callback(statusCode)); - } - - public abstract void callback(int statusCode); - - @Override - public int getInterfaceVersion() { - return this.VERSION; - } - - @Override - public String getInterfaceHash() { - return this.HASH; - } - } - - private class DhcpServerCallbacksImpl extends DhcpServerCallbacks { - private final int mStartIndex; - - private DhcpServerCallbacksImpl(int startIndex) { - mStartIndex = startIndex; - } - - @Override - public void onDhcpServerCreated(int statusCode, IDhcpServer server) throws RemoteException { - getHandler().post(() -> { - // We are on the handler thread: mDhcpServerStartIndex can be read safely. - if (mStartIndex != mDhcpServerStartIndex) { - // This start request is obsolete. Explicitly stop the DHCP server to shut - // down its thread. When the |server| binder token goes out of scope, the - // garbage collector will finalize it, which causes the network stack process - // garbage collector to collect the server itself. - try { - server.stop(null); - } catch (RemoteException e) { } - return; - } - - if (statusCode != STATUS_SUCCESS) { - mLog.e("Error obtaining DHCP server: " + statusCode); - handleError(); - return; - } - - mDhcpServer = server; - try { - mDhcpServer.startWithCallbacks(new OnHandlerStatusCallback() { - @Override - public void callback(int startStatusCode) { - if (startStatusCode != STATUS_SUCCESS) { - mLog.e("Error starting DHCP server: " + startStatusCode); - handleError(); - } - } - }, new DhcpEventCallback()); - } catch (RemoteException e) { - throw new IllegalStateException(e); - } - }); - } - - private void handleError() { - mLastError = TetheringManager.TETHER_ERROR_DHCPSERVER_ERROR; - transitionTo(mInitialState); - } - } - - private class DhcpEventCallback extends IDhcpEventCallbacks.Stub { - @Override - public void onLeasesChanged(List<DhcpLeaseParcelable> leaseParcelables) { - final ArrayList<TetheredClient> leases = new ArrayList<>(); - for (DhcpLeaseParcelable lease : leaseParcelables) { - final LinkAddress address = new LinkAddress( - intToInet4AddressHTH(lease.netAddr), lease.prefixLength, - 0 /* flags */, RT_SCOPE_UNIVERSE /* as per RFC6724#3.2 */, - lease.expTime /* deprecationTime */, lease.expTime /* expirationTime */); - - final MacAddress macAddress; - try { - macAddress = MacAddress.fromBytes(lease.hwAddr); - } catch (IllegalArgumentException e) { - Log.wtf(TAG, "Invalid address received from DhcpServer: " - + Arrays.toString(lease.hwAddr)); - return; - } - - final TetheredClient.AddressInfo addressInfo = new TetheredClient.AddressInfo( - address, lease.hostname); - leases.add(new TetheredClient( - macAddress, - Collections.singletonList(addressInfo), - mInterfaceType)); - } - - getHandler().post(() -> { - mDhcpLeases = leases; - mCallback.dhcpLeasesChanged(); - }); - } - - @Override - public void onNewPrefixRequest(@NonNull final IpPrefix currentPrefix) { - Objects.requireNonNull(currentPrefix); - sendMessage(CMD_NEW_PREFIX_REQUEST, currentPrefix); - } - - @Override - public int getInterfaceVersion() { - return this.VERSION; - } - - @Override - public String getInterfaceHash() throws RemoteException { - return this.HASH; - } - } - - private RouteInfo getDirectConnectedRoute(@NonNull final LinkAddress ipv4Address) { - Objects.requireNonNull(ipv4Address); - return new RouteInfo(PrefixUtils.asIpPrefix(ipv4Address), null, mIfaceName, RTN_UNICAST); - } - - private DhcpServingParamsParcel makeServingParams(@NonNull final Inet4Address defaultRouter, - @NonNull final Inet4Address dnsServer, @NonNull LinkAddress serverAddr, - @Nullable Inet4Address clientAddr) { - final boolean changePrefixOnDecline = - (mInterfaceType == TetheringManager.TETHERING_NCM && clientAddr == null); - return new DhcpServingParamsParcelExt() - .setDefaultRouters(defaultRouter) - .setDhcpLeaseTimeSecs(DHCP_LEASE_TIME_SECS) - .setDnsServers(dnsServer) - .setServerAddr(serverAddr) - .setMetered(true) - .setSingleClientAddr(clientAddr) - .setChangePrefixOnDecline(changePrefixOnDecline); - // TODO: also advertise link MTU - } - - private boolean startDhcp(final LinkAddress serverLinkAddr, final LinkAddress clientLinkAddr) { - if (mUsingLegacyDhcp) { - return true; - } - - final Inet4Address addr = (Inet4Address) serverLinkAddr.getAddress(); - final Inet4Address clientAddr = clientLinkAddr == null ? null : - (Inet4Address) clientLinkAddr.getAddress(); - - final DhcpServingParamsParcel params = makeServingParams(addr /* defaultRouter */, - addr /* dnsServer */, serverLinkAddr, clientAddr); - mDhcpServerStartIndex++; - mDeps.makeDhcpServer( - mIfaceName, params, new DhcpServerCallbacksImpl(mDhcpServerStartIndex)); - return true; - } - - private void stopDhcp() { - // Make all previous start requests obsolete so servers are not started later - mDhcpServerStartIndex++; - - if (mDhcpServer != null) { - try { - mDhcpServer.stop(new OnHandlerStatusCallback() { - @Override - public void callback(int statusCode) { - if (statusCode != STATUS_SUCCESS) { - mLog.e("Error stopping DHCP server: " + statusCode); - mLastError = TetheringManager.TETHER_ERROR_DHCPSERVER_ERROR; - // Not much more we can do here - } - mDhcpLeases.clear(); - getHandler().post(mCallback::dhcpLeasesChanged); - } - }); - mDhcpServer = null; - } catch (RemoteException e) { - mLog.e("Error stopping DHCP server", e); - // Not much more we can do here - } - } - } - - private boolean configureDhcp(boolean enable, final LinkAddress serverAddr, - final LinkAddress clientAddr) { - if (enable) { - return startDhcp(serverAddr, clientAddr); - } else { - stopDhcp(); - return true; - } - } - - private void stopIPv4() { - configureIPv4(false); - // NOTE: All of configureIPv4() will be refactored out of existence - // into calls to InterfaceController, shared with startIPv4(). - mInterfaceCtrl.clearIPv4Address(); - mPrivateAddressCoordinator.releaseDownstream(this); - mIpv4Address = null; - mStaticIpv4ServerAddr = null; - mStaticIpv4ClientAddr = null; - } - - private boolean configureIPv4(boolean enabled) { - if (VDBG) Log.d(TAG, "configureIPv4(" + enabled + ")"); - - if (enabled) { - mIpv4Address = requestIpv4Address(true /* useLastAddress */); - } - - if (mIpv4Address == null) { - mLog.e("No available ipv4 address"); - return false; - } - - if (mInterfaceType == TetheringManager.TETHERING_BLUETOOTH) { - // BT configures the interface elsewhere: only start DHCP. - // TODO: make all tethering types behave the same way, and delete the bluetooth - // code that calls into NetworkManagementService directly. - return configureDhcp(enabled, mIpv4Address, null /* clientAddress */); - } - - final IpPrefix ipv4Prefix = asIpPrefix(mIpv4Address); - - final Boolean setIfaceUp; - if (mInterfaceType == TetheringManager.TETHERING_WIFI - || mInterfaceType == TetheringManager.TETHERING_WIFI_P2P - || mInterfaceType == TetheringManager.TETHERING_ETHERNET - || mInterfaceType == TetheringManager.TETHERING_WIGIG) { - // The WiFi and Ethernet stack has ownership of the interface up/down state. - // It is unclear whether the Bluetooth or USB stacks will manage their own - // state. - setIfaceUp = null; - } else { - setIfaceUp = enabled; - } - if (!mInterfaceCtrl.setInterfaceConfiguration(mIpv4Address, setIfaceUp)) { - mLog.e("Error configuring interface"); - if (!enabled) stopDhcp(); - return false; - } - - if (enabled) { - mLinkProperties.addLinkAddress(mIpv4Address); - mLinkProperties.addRoute(getDirectConnectedRoute(mIpv4Address)); - } else { - mLinkProperties.removeLinkAddress(mIpv4Address); - mLinkProperties.removeRoute(getDirectConnectedRoute(mIpv4Address)); - } - return configureDhcp(enabled, mIpv4Address, mStaticIpv4ClientAddr); - } - - private LinkAddress requestIpv4Address(final boolean useLastAddress) { - if (mStaticIpv4ServerAddr != null) return mStaticIpv4ServerAddr; - - if (mInterfaceType == TetheringManager.TETHERING_BLUETOOTH) { - return new LinkAddress(BLUETOOTH_IFACE_ADDR); - } - - return mPrivateAddressCoordinator.requestDownstreamAddress(this, useLastAddress); - } - - private boolean startIPv6() { - mInterfaceParams = mDeps.getInterfaceParams(mIfaceName); - if (mInterfaceParams == null) { - mLog.e("Failed to find InterfaceParams"); - stopIPv6(); - return false; - } - - mRaDaemon = mDeps.getRouterAdvertisementDaemon(mInterfaceParams); - if (!mRaDaemon.start()) { - stopIPv6(); - return false; - } - - // TODO: use ShimUtils instead of explicitly checking the version here. - if (Build.VERSION.SDK_INT > Build.VERSION_CODES.R || "S".equals(Build.VERSION.CODENAME) - || "T".equals(Build.VERSION.CODENAME)) { - // DAD Proxy starts forwarding packets after IPv6 upstream is present. - mDadProxy = mDeps.getDadProxy(getHandler(), mInterfaceParams); - } - - return true; - } - - private void stopIPv6() { - mInterfaceParams = null; - setRaParams(null); - - if (mRaDaemon != null) { - mRaDaemon.stop(); - mRaDaemon = null; - } - - if (mDadProxy != null) { - mDadProxy.stop(); - mDadProxy = null; - } - } - - // IPv6TetheringCoordinator sends updates with carefully curated IPv6-only - // LinkProperties. These have extraneous data filtered out and only the - // necessary prefixes included (per its prefix distribution policy). - // - // TODO: Evaluate using a data structure than is more directly suited to - // communicating only the relevant information. - private void updateUpstreamIPv6LinkProperties(LinkProperties v6only, int ttlAdjustment) { - if (mRaDaemon == null) return; - - // Avoid unnecessary work on spurious updates. - if (Objects.equals(mLastIPv6LinkProperties, v6only)) { - return; - } - - RaParams params = null; - String upstreamIface = null; - InterfaceParams upstreamIfaceParams = null; - int upstreamIfIndex = 0; - - if (v6only != null) { - upstreamIface = v6only.getInterfaceName(); - upstreamIfaceParams = mDeps.getInterfaceParams(upstreamIface); - if (upstreamIfaceParams != null) { - upstreamIfIndex = upstreamIfaceParams.index; - } - params = new RaParams(); - params.mtu = v6only.getMtu(); - params.hasDefaultRoute = v6only.hasIpv6DefaultRoute(); - - if (params.hasDefaultRoute) params.hopLimit = getHopLimit(upstreamIface, ttlAdjustment); - - for (LinkAddress linkAddr : v6only.getLinkAddresses()) { - if (linkAddr.getPrefixLength() != RFC7421_PREFIX_LENGTH) continue; - - final IpPrefix prefix = new IpPrefix( - linkAddr.getAddress(), linkAddr.getPrefixLength()); - params.prefixes.add(prefix); - - final Inet6Address dnsServer = getLocalDnsIpFor(prefix); - if (dnsServer != null) { - params.dnses.add(dnsServer); - } - } - - // Add upstream index to name mapping for the tether stats usage in the coordinator. - // Although this mapping could be added by both class Tethering and IpServer, adding - // mapping from IpServer guarantees that the mapping is added before the adding - // forwarding rules. That is because there are different state machines in both - // classes. It is hard to guarantee the link property update order between multiple - // state machines. - mBpfCoordinator.addUpstreamNameToLookupTable(upstreamIfIndex, upstreamIface); - } - - // If v6only is null, we pass in null to setRaParams(), which handles - // deprecation of any existing RA data. - - setRaParams(params); - mLastIPv6LinkProperties = v6only; - - updateIpv6ForwardingRules(mLastIPv6UpstreamIfindex, upstreamIfIndex, null); - mLastIPv6UpstreamIfindex = upstreamIfIndex; - if (mDadProxy != null) { - mDadProxy.setUpstreamIface(upstreamIfaceParams); - } - } - - private void removeRoutesFromLocalNetwork(@NonNull final List<RouteInfo> toBeRemoved) { - final int removalFailures = RouteUtils.removeRoutesFromLocalNetwork( - mNetd, toBeRemoved); - if (removalFailures > 0) { - mLog.e(String.format("Failed to remove %d IPv6 routes from local table.", - removalFailures)); - } - - for (RouteInfo route : toBeRemoved) mLinkProperties.removeRoute(route); - } - - private void addRoutesToLocalNetwork(@NonNull final List<RouteInfo> toBeAdded) { - try { - // It's safe to call networkAddInterface() even if - // the interface is already in the local_network. - mNetd.networkAddInterface(INetd.LOCAL_NET_ID, mIfaceName); - try { - // Add routes from local network. Note that adding routes that - // already exist does not cause an error (EEXIST is silently ignored). - RouteUtils.addRoutesToLocalNetwork(mNetd, mIfaceName, toBeAdded); - } catch (IllegalStateException e) { - mLog.e("Failed to add IPv4/v6 routes to local table: " + e); - return; - } - } catch (ServiceSpecificException | RemoteException e) { - mLog.e("Failed to add " + mIfaceName + " to local table: ", e); - return; - } - - for (RouteInfo route : toBeAdded) mLinkProperties.addRoute(route); - } - - private void configureLocalIPv6Routes( - HashSet<IpPrefix> deprecatedPrefixes, HashSet<IpPrefix> newPrefixes) { - // [1] Remove the routes that are deprecated. - if (!deprecatedPrefixes.isEmpty()) { - removeRoutesFromLocalNetwork(getLocalRoutesFor(mIfaceName, deprecatedPrefixes)); - } - - // [2] Add only the routes that have not previously been added. - if (newPrefixes != null && !newPrefixes.isEmpty()) { - HashSet<IpPrefix> addedPrefixes = (HashSet) newPrefixes.clone(); - if (mLastRaParams != null) { - addedPrefixes.removeAll(mLastRaParams.prefixes); - } - - if (!addedPrefixes.isEmpty()) { - addRoutesToLocalNetwork(getLocalRoutesFor(mIfaceName, addedPrefixes)); - } - } - } - - private void configureLocalIPv6Dns( - HashSet<Inet6Address> deprecatedDnses, HashSet<Inet6Address> newDnses) { - // TODO: Is this really necessary? Can we not fail earlier if INetd cannot be located? - if (mNetd == null) { - if (newDnses != null) newDnses.clear(); - mLog.e("No netd service instance available; not setting local IPv6 addresses"); - return; - } - - // [1] Remove deprecated local DNS IP addresses. - if (!deprecatedDnses.isEmpty()) { - for (Inet6Address dns : deprecatedDnses) { - if (!mInterfaceCtrl.removeAddress(dns, RFC7421_PREFIX_LENGTH)) { - mLog.e("Failed to remove local dns IP " + dns); - } - - mLinkProperties.removeLinkAddress(new LinkAddress(dns, RFC7421_PREFIX_LENGTH)); - } - } - - // [2] Add only the local DNS IP addresses that have not previously been added. - if (newDnses != null && !newDnses.isEmpty()) { - final HashSet<Inet6Address> addedDnses = (HashSet) newDnses.clone(); - if (mLastRaParams != null) { - addedDnses.removeAll(mLastRaParams.dnses); - } - - for (Inet6Address dns : addedDnses) { - if (!mInterfaceCtrl.addAddress(dns, RFC7421_PREFIX_LENGTH)) { - mLog.e("Failed to add local dns IP " + dns); - newDnses.remove(dns); - } - - mLinkProperties.addLinkAddress(new LinkAddress(dns, RFC7421_PREFIX_LENGTH)); - } - } - - try { - mNetd.tetherApplyDnsInterfaces(); - } catch (ServiceSpecificException | RemoteException e) { - mLog.e("Failed to update local DNS caching server"); - if (newDnses != null) newDnses.clear(); - } - } - - private void addIpv6ForwardingRule(Ipv6ForwardingRule rule) { - // Theoretically, we don't need this check because IP neighbor monitor doesn't start if BPF - // offload is disabled. Add this check just in case. - // TODO: Perhaps remove this protection check. - if (!mUsingBpfOffload) return; - - mBpfCoordinator.tetherOffloadRuleAdd(this, rule); - } - - private void removeIpv6ForwardingRule(Ipv6ForwardingRule rule) { - // TODO: Perhaps remove this protection check. - // See the related comment in #addIpv6ForwardingRule. - if (!mUsingBpfOffload) return; - - mBpfCoordinator.tetherOffloadRuleRemove(this, rule); - } - - private void clearIpv6ForwardingRules() { - if (!mUsingBpfOffload) return; - - mBpfCoordinator.tetherOffloadRuleClear(this); - } - - private void updateIpv6ForwardingRule(int newIfindex) { - // TODO: Perhaps remove this protection check. - // See the related comment in #addIpv6ForwardingRule. - if (!mUsingBpfOffload) return; - - mBpfCoordinator.tetherOffloadRuleUpdate(this, newIfindex); - } - - // Handles all updates to IPv6 forwarding rules. These can currently change only if the upstream - // changes or if a neighbor event is received. - private void updateIpv6ForwardingRules(int prevUpstreamIfindex, int upstreamIfindex, - NeighborEvent e) { - // If we no longer have an upstream, clear forwarding rules and do nothing else. - if (upstreamIfindex == 0) { - clearIpv6ForwardingRules(); - return; - } - - // If the upstream interface has changed, remove all rules and re-add them with the new - // upstream interface. - if (prevUpstreamIfindex != upstreamIfindex) { - updateIpv6ForwardingRule(upstreamIfindex); - } - - // If we're here to process a NeighborEvent, do so now. - // mInterfaceParams must be non-null or the event would not have arrived. - if (e == null) return; - if (!(e.ip instanceof Inet6Address) || e.ip.isMulticastAddress() - || e.ip.isLoopbackAddress() || e.ip.isLinkLocalAddress()) { - return; - } - - // When deleting rules, we still need to pass a non-null MAC, even though it's ignored. - // Do this here instead of in the Ipv6ForwardingRule constructor to ensure that we never - // add rules with a null MAC, only delete them. - MacAddress dstMac = e.isValid() ? e.macAddr : NULL_MAC_ADDRESS; - Ipv6ForwardingRule rule = new Ipv6ForwardingRule(upstreamIfindex, - mInterfaceParams.index, (Inet6Address) e.ip, mInterfaceParams.macAddr, dstMac); - if (e.isValid()) { - addIpv6ForwardingRule(rule); - } else { - removeIpv6ForwardingRule(rule); - } - } - - private void handleNeighborEvent(NeighborEvent e) { - if (mInterfaceParams != null - && mInterfaceParams.index == e.ifindex - && mInterfaceParams.hasMacAddress) { - updateIpv6ForwardingRules(mLastIPv6UpstreamIfindex, mLastIPv6UpstreamIfindex, e); - } - } - - private void handleNewPrefixRequest(@NonNull final IpPrefix currentPrefix) { - if (!currentPrefix.contains(mIpv4Address.getAddress()) - || currentPrefix.getPrefixLength() != mIpv4Address.getPrefixLength()) { - Log.e(TAG, "Invalid prefix: " + currentPrefix); - return; - } - - final LinkAddress deprecatedLinkAddress = mIpv4Address; - mIpv4Address = requestIpv4Address(false); - if (mIpv4Address == null) { - mLog.e("Fail to request a new downstream prefix"); - return; - } - final Inet4Address srvAddr = (Inet4Address) mIpv4Address.getAddress(); - - // Add new IPv4 address on the interface. - if (!mInterfaceCtrl.addAddress(srvAddr, currentPrefix.getPrefixLength())) { - mLog.e("Failed to add new IP " + srvAddr); - return; - } - - // Remove deprecated routes from local network. - removeRoutesFromLocalNetwork( - Collections.singletonList(getDirectConnectedRoute(deprecatedLinkAddress))); - mLinkProperties.removeLinkAddress(deprecatedLinkAddress); - - // Add new routes to local network. - addRoutesToLocalNetwork( - Collections.singletonList(getDirectConnectedRoute(mIpv4Address))); - mLinkProperties.addLinkAddress(mIpv4Address); - - // Update local DNS caching server with new IPv4 address, otherwise, dnsmasq doesn't - // listen on the interface configured with new IPv4 address, that results DNS validation - // failure of downstream client even if appropriate routes have been configured. - try { - mNetd.tetherApplyDnsInterfaces(); - } catch (ServiceSpecificException | RemoteException e) { - mLog.e("Failed to update local DNS caching server"); - return; - } - sendLinkProperties(); - - // Notify DHCP server that new prefix/route has been applied on IpServer. - final Inet4Address clientAddr = mStaticIpv4ClientAddr == null ? null : - (Inet4Address) mStaticIpv4ClientAddr.getAddress(); - final DhcpServingParamsParcel params = makeServingParams(srvAddr /* defaultRouter */, - srvAddr /* dnsServer */, mIpv4Address /* serverLinkAddress */, clientAddr); - try { - mDhcpServer.updateParams(params, new OnHandlerStatusCallback() { - @Override - public void callback(int statusCode) { - if (statusCode != STATUS_SUCCESS) { - mLog.e("Error updating DHCP serving params: " + statusCode); - } - } - }); - } catch (RemoteException e) { - mLog.e("Error updating DHCP serving params", e); - } - } - - private byte getHopLimit(String upstreamIface, int adjustTTL) { - try { - int upstreamHopLimit = Integer.parseUnsignedInt( - mNetd.getProcSysNet(INetd.IPV6, INetd.CONF, upstreamIface, "hop_limit")); - upstreamHopLimit = upstreamHopLimit + adjustTTL; - // Cap the hop limit to 255. - return (byte) Integer.min(upstreamHopLimit, 255); - } catch (Exception e) { - mLog.e("Failed to find upstream interface hop limit", e); - } - return RaParams.DEFAULT_HOPLIMIT; - } - - private void setRaParams(RaParams newParams) { - if (mRaDaemon != null) { - final RaParams deprecatedParams = - RaParams.getDeprecatedRaParams(mLastRaParams, newParams); - - configureLocalIPv6Routes(deprecatedParams.prefixes, - (newParams != null) ? newParams.prefixes : null); - - configureLocalIPv6Dns(deprecatedParams.dnses, - (newParams != null) ? newParams.dnses : null); - - mRaDaemon.buildNewRa(deprecatedParams, newParams); - } - - mLastRaParams = newParams; - } - - private void logMessage(State state, int what) { - mLog.log(state.getName() + " got " + sMagicDecoderRing.get(what, Integer.toString(what))); - } - - private void sendInterfaceState(int newInterfaceState) { - mServingMode = newInterfaceState; - mCallback.updateInterfaceState(this, newInterfaceState, mLastError); - sendLinkProperties(); - } - - private void sendLinkProperties() { - mCallback.updateLinkProperties(this, new LinkProperties(mLinkProperties)); - } - - private void resetLinkProperties() { - mLinkProperties.clear(); - mLinkProperties.setInterfaceName(mIfaceName); - } - - private void maybeConfigureStaticIp(final TetheringRequestParcel request) { - // Ignore static address configuration if they are invalid or null. In theory, static - // addresses should not be invalid here because TetheringManager do not allow caller to - // specify invalid static address configuration. - if (request == null || request.localIPv4Address == null - || request.staticClientAddress == null || !checkStaticAddressConfiguration( - request.localIPv4Address, request.staticClientAddress)) { - return; - } - - mStaticIpv4ServerAddr = request.localIPv4Address; - mStaticIpv4ClientAddr = request.staticClientAddress; - } - - class InitialState extends State { - @Override - public void enter() { - sendInterfaceState(STATE_AVAILABLE); - } - - @Override - public boolean processMessage(Message message) { - logMessage(this, message.what); - switch (message.what) { - case CMD_TETHER_REQUESTED: - mLastError = TetheringManager.TETHER_ERROR_NO_ERROR; - switch (message.arg1) { - case STATE_LOCAL_ONLY: - maybeConfigureStaticIp((TetheringRequestParcel) message.obj); - transitionTo(mLocalHotspotState); - break; - case STATE_TETHERED: - maybeConfigureStaticIp((TetheringRequestParcel) message.obj); - transitionTo(mTetheredState); - break; - default: - mLog.e("Invalid tethering interface serving state specified."); - } - break; - case CMD_INTERFACE_DOWN: - transitionTo(mUnavailableState); - break; - case CMD_IPV6_TETHER_UPDATE: - updateUpstreamIPv6LinkProperties((LinkProperties) message.obj, message.arg1); - break; - default: - return NOT_HANDLED; - } - return HANDLED; - } - } - - class BaseServingState extends State { - @Override - public void enter() { - if (!startIPv4()) { - mLastError = TetheringManager.TETHER_ERROR_IFACE_CFG_ERROR; - return; - } - - try { - NetdUtils.tetherInterface(mNetd, mIfaceName, asIpPrefix(mIpv4Address)); - } catch (RemoteException | ServiceSpecificException | IllegalStateException e) { - mLog.e("Error Tethering", e); - mLastError = TetheringManager.TETHER_ERROR_TETHER_IFACE_ERROR; - return; - } - - if (!startIPv6()) { - mLog.e("Failed to startIPv6"); - // TODO: Make this a fatal error once Bluetooth IPv6 is sorted. - return; - } - } - - @Override - public void exit() { - // Note that at this point, we're leaving the tethered state. We can fail any - // of these operations, but it doesn't really change that we have to try them - // all in sequence. - stopIPv6(); - - try { - NetdUtils.untetherInterface(mNetd, mIfaceName); - } catch (RemoteException | ServiceSpecificException e) { - mLastError = TetheringManager.TETHER_ERROR_UNTETHER_IFACE_ERROR; - mLog.e("Failed to untether interface: " + e); - } - - stopIPv4(); - - resetLinkProperties(); - } - - @Override - public boolean processMessage(Message message) { - logMessage(this, message.what); - switch (message.what) { - case CMD_TETHER_UNREQUESTED: - transitionTo(mInitialState); - if (DBG) Log.d(TAG, "Untethered (unrequested)" + mIfaceName); - break; - case CMD_INTERFACE_DOWN: - transitionTo(mUnavailableState); - if (DBG) Log.d(TAG, "Untethered (ifdown)" + mIfaceName); - break; - case CMD_IPV6_TETHER_UPDATE: - updateUpstreamIPv6LinkProperties((LinkProperties) message.obj, message.arg1); - sendLinkProperties(); - break; - case CMD_IP_FORWARDING_ENABLE_ERROR: - case CMD_IP_FORWARDING_DISABLE_ERROR: - case CMD_START_TETHERING_ERROR: - case CMD_STOP_TETHERING_ERROR: - case CMD_SET_DNS_FORWARDERS_ERROR: - mLastError = TetheringManager.TETHER_ERROR_INTERNAL_ERROR; - transitionTo(mInitialState); - break; - case CMD_NEW_PREFIX_REQUEST: - handleNewPrefixRequest((IpPrefix) message.obj); - break; - case CMD_NOTIFY_PREFIX_CONFLICT: - mLog.i("restart tethering: " + mInterfaceType); - mCallback.requestEnableTethering(mInterfaceType, false /* enabled */); - transitionTo(mWaitingForRestartState); - break; - default: - return false; - } - return true; - } - } - - // Handling errors in BaseServingState.enter() by transitioning is - // problematic because transitioning during a multi-state jump yields - // a Log.wtf(). Ultimately, there should be only one ServingState, - // and forwarding and NAT rules should be handled by a coordinating - // functional element outside of IpServer. - class LocalHotspotState extends BaseServingState { - @Override - public void enter() { - super.enter(); - if (mLastError != TetheringManager.TETHER_ERROR_NO_ERROR) { - transitionTo(mInitialState); - } - - if (DBG) Log.d(TAG, "Local hotspot " + mIfaceName); - sendInterfaceState(STATE_LOCAL_ONLY); - } - - @Override - public boolean processMessage(Message message) { - if (super.processMessage(message)) return true; - - logMessage(this, message.what); - switch (message.what) { - case CMD_TETHER_REQUESTED: - mLog.e("CMD_TETHER_REQUESTED while in local-only hotspot mode."); - break; - case CMD_TETHER_CONNECTION_CHANGED: - // Ignored in local hotspot state. - break; - default: - return false; - } - return true; - } - } - - // Handling errors in BaseServingState.enter() by transitioning is - // problematic because transitioning during a multi-state jump yields - // a Log.wtf(). Ultimately, there should be only one ServingState, - // and forwarding and NAT rules should be handled by a coordinating - // functional element outside of IpServer. - class TetheredState extends BaseServingState { - @Override - public void enter() { - super.enter(); - if (mLastError != TetheringManager.TETHER_ERROR_NO_ERROR) { - transitionTo(mInitialState); - } - - if (DBG) Log.d(TAG, "Tethered " + mIfaceName); - sendInterfaceState(STATE_TETHERED); - } - - @Override - public void exit() { - cleanupUpstream(); - super.exit(); - } - - private void cleanupUpstream() { - if (mUpstreamIfaceSet == null) return; - - for (String ifname : mUpstreamIfaceSet.ifnames) cleanupUpstreamInterface(ifname); - mUpstreamIfaceSet = null; - clearIpv6ForwardingRules(); - } - - private void cleanupUpstreamInterface(String upstreamIface) { - // Note that we don't care about errors here. - // Sometimes interfaces are gone before we get - // to remove their rules, which generates errors. - // Just do the best we can. - try { - mNetd.ipfwdRemoveInterfaceForward(mIfaceName, upstreamIface); - } catch (RemoteException | ServiceSpecificException e) { - mLog.e("Exception in ipfwdRemoveInterfaceForward: " + e.toString()); - } - try { - mNetd.tetherRemoveForward(mIfaceName, upstreamIface); - } catch (RemoteException | ServiceSpecificException e) { - mLog.e("Exception in disableNat: " + e.toString()); - } - } - - @Override - public boolean processMessage(Message message) { - if (super.processMessage(message)) return true; - - logMessage(this, message.what); - switch (message.what) { - case CMD_TETHER_REQUESTED: - mLog.e("CMD_TETHER_REQUESTED while already tethering."); - break; - case CMD_TETHER_CONNECTION_CHANGED: - final InterfaceSet newUpstreamIfaceSet = (InterfaceSet) message.obj; - if (noChangeInUpstreamIfaceSet(newUpstreamIfaceSet)) { - if (VDBG) Log.d(TAG, "Connection changed noop - dropping"); - break; - } - - if (newUpstreamIfaceSet == null) { - cleanupUpstream(); - break; - } - - for (String removed : upstreamInterfacesRemoved(newUpstreamIfaceSet)) { - cleanupUpstreamInterface(removed); - } - - final Set<String> added = upstreamInterfacesAdd(newUpstreamIfaceSet); - // This makes the call to cleanupUpstream() in the error - // path for any interface neatly cleanup all the interfaces. - mUpstreamIfaceSet = newUpstreamIfaceSet; - - for (String ifname : added) { - try { - mNetd.tetherAddForward(mIfaceName, ifname); - mNetd.ipfwdAddInterfaceForward(mIfaceName, ifname); - } catch (RemoteException | ServiceSpecificException e) { - mLog.e("Exception enabling NAT: " + e.toString()); - cleanupUpstream(); - mLastError = TetheringManager.TETHER_ERROR_ENABLE_FORWARDING_ERROR; - transitionTo(mInitialState); - return true; - } - } - break; - case CMD_NEIGHBOR_EVENT: - handleNeighborEvent((NeighborEvent) message.obj); - break; - default: - return false; - } - return true; - } - - private boolean noChangeInUpstreamIfaceSet(InterfaceSet newIfaces) { - if (mUpstreamIfaceSet == null && newIfaces == null) return true; - if (mUpstreamIfaceSet != null && newIfaces != null) { - return mUpstreamIfaceSet.equals(newIfaces); - } - return false; - } - - private Set<String> upstreamInterfacesRemoved(InterfaceSet newIfaces) { - if (mUpstreamIfaceSet == null) return new HashSet<>(); - - final HashSet<String> removed = new HashSet<>(mUpstreamIfaceSet.ifnames); - removed.removeAll(newIfaces.ifnames); - return removed; - } - - private Set<String> upstreamInterfacesAdd(InterfaceSet newIfaces) { - final HashSet<String> added = new HashSet<>(newIfaces.ifnames); - if (mUpstreamIfaceSet != null) added.removeAll(mUpstreamIfaceSet.ifnames); - return added; - } - } - - /** - * This state is terminal for the per interface state machine. At this - * point, the tethering main state machine should have removed this interface - * specific state machine from its list of possible recipients of - * tethering requests. The state machine itself will hang around until - * the garbage collector finds it. - */ - class UnavailableState extends State { - @Override - public void enter() { - mIpNeighborMonitor.stop(); - mLastError = TetheringManager.TETHER_ERROR_NO_ERROR; - sendInterfaceState(STATE_UNAVAILABLE); - } - } - - class WaitingForRestartState extends State { - @Override - public boolean processMessage(Message message) { - logMessage(this, message.what); - switch (message.what) { - case CMD_TETHER_UNREQUESTED: - transitionTo(mInitialState); - mLog.i("Untethered (unrequested) and restarting " + mIfaceName); - mCallback.requestEnableTethering(mInterfaceType, true /* enabled */); - break; - case CMD_INTERFACE_DOWN: - transitionTo(mUnavailableState); - mLog.i("Untethered (interface down) and restarting" + mIfaceName); - mCallback.requestEnableTethering(mInterfaceType, true /* enabled */); - break; - default: - return false; - } - return true; - } - } - - // Accumulate routes representing "prefixes to be assigned to the local - // interface", for subsequent modification of local_network routing. - private static ArrayList<RouteInfo> getLocalRoutesFor( - String ifname, HashSet<IpPrefix> prefixes) { - final ArrayList<RouteInfo> localRoutes = new ArrayList<RouteInfo>(); - for (IpPrefix ipp : prefixes) { - localRoutes.add(new RouteInfo(ipp, null, ifname, RTN_UNICAST)); - } - return localRoutes; - } - - // Given a prefix like 2001:db8::/64 return an address like 2001:db8::1. - private static Inet6Address getLocalDnsIpFor(IpPrefix localPrefix) { - final byte[] dnsBytes = localPrefix.getRawAddress(); - dnsBytes[dnsBytes.length - 1] = getRandomSanitizedByte(DOUG_ADAMS, asByte(0), asByte(1)); - try { - return Inet6Address.getByAddress(null, dnsBytes, 0); - } catch (UnknownHostException e) { - Log.wtf(TAG, "Failed to construct Inet6Address from: " + localPrefix); - return null; - } - } - - private static byte getRandomSanitizedByte(byte dflt, byte... excluded) { - final byte random = (byte) (new Random()).nextInt(); - for (int value : excluded) { - if (random == value) return dflt; - } - return random; - } -} |