Support MirrorLink DHCPDECLINE.
Add the specific implementation of onNewPrefixRequest callback
on IpServer side, also refactor some common code.
Bug: 130741856
Test: atest TetheringTests
Change-Id: If2871bf899cb5890bbfee18063a194c92b6f474e
diff --git a/Tethering/src/android/net/ip/IpServer.java b/Tethering/src/android/net/ip/IpServer.java
index d993306..de53787 100644
--- a/Tethering/src/android/net/ip/IpServer.java
+++ b/Tethering/src/android/net/ip/IpServer.java
@@ -50,6 +50,7 @@
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.Handler;
import android.os.Looper;
@@ -60,6 +61,7 @@
import android.util.SparseArray;
import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
import com.android.internal.util.MessageUtils;
import com.android.internal.util.State;
@@ -115,6 +117,15 @@
private static final String ETHERNET_IFACE_ADDR = "192.168.50.1";
private static final int ETHERNET_IFACE_PREFIX_LENGTH = 24;
+ // TODO: remove this constant after introducing PrivateAddressCoordinator.
+ private static final List<IpPrefix> NCM_PREFIXES = Collections.unmodifiableList(
+ Arrays.asList(
+ new IpPrefix("192.168.42.0/24"),
+ new IpPrefix("192.168.51.0/24"),
+ new IpPrefix("192.168.52.0/24"),
+ new IpPrefix("192.168.53.0/24")
+ ));
+
// TODO: have PanService use some visible version of this constant
private static final String BLUETOOTH_IFACE_ADDR = "192.168.44.1";
private static final int BLUETOOTH_DHCP_PREFIX_LENGTH = 24;
@@ -212,6 +223,8 @@
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;
private final State mInitialState;
private final State mLocalHotspotState;
@@ -462,7 +475,7 @@
handleError();
}
}
- }, new DhcpLeaseCallback());
+ }, new DhcpEventCallback());
} catch (RemoteException e) {
throw new IllegalStateException(e);
}
@@ -475,7 +488,7 @@
}
}
- private class DhcpLeaseCallback extends IDhcpEventCallbacks.Stub {
+ private class DhcpEventCallback extends IDhcpEventCallbacks.Stub {
@Override
public void onLeasesChanged(List<DhcpLeaseParcelable> leaseParcelables) {
final ArrayList<TetheredClient> leases = new ArrayList<>();
@@ -509,8 +522,9 @@
}
@Override
- public void onNewPrefixRequest(IpPrefix currentPrefix) {
- //TODO: add specific implementation.
+ public void onNewPrefixRequest(@NonNull final IpPrefix currentPrefix) {
+ Objects.requireNonNull(currentPrefix);
+ sendMessage(CMD_NEW_PREFIX_REQUEST, currentPrefix);
}
@Override
@@ -524,26 +538,38 @@
}
}
+ 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 int prefixLen = serverLinkAddr.getPrefixLength();
final Inet4Address clientAddr = clientLinkAddr == null ? null :
(Inet4Address) clientLinkAddr.getAddress();
- final DhcpServingParamsParcel params;
- params = new DhcpServingParamsParcelExt()
- .setDefaultRouters(addr)
- .setDhcpLeaseTimeSecs(DHCP_LEASE_TIME_SECS)
- .setDnsServers(addr)
- .setServerAddr(serverLinkAddr)
- .setMetered(true)
- .setSingleClientAddr(clientAddr);
- // TODO: also advertise link MTU
-
+ final DhcpServingParamsParcel params = makeServingParams(addr /* defaultRouter */,
+ addr /* dnsServer */, serverLinkAddr, clientAddr);
mDhcpServerStartIndex++;
mDeps.makeDhcpServer(
mIfaceName, params, new DhcpServerCallbacksImpl(mDhcpServerStartIndex));
@@ -570,7 +596,7 @@
});
mDhcpServer = null;
} catch (RemoteException e) {
- mLog.e("Error stopping DHCP", e);
+ mLog.e("Error stopping DHCP server", e);
// Not much more we can do here
}
}
@@ -652,31 +678,33 @@
return false;
}
- // Directly-connected route.
- final IpPrefix ipv4Prefix = new IpPrefix(mIpv4Address.getAddress(),
- mIpv4Address.getPrefixLength());
- final RouteInfo route = new RouteInfo(ipv4Prefix, null, null, RTN_UNICAST);
if (enabled) {
mLinkProperties.addLinkAddress(mIpv4Address);
- mLinkProperties.addRoute(route);
+ mLinkProperties.addRoute(getDirectConnectedRoute(mIpv4Address));
} else {
mLinkProperties.removeLinkAddress(mIpv4Address);
- mLinkProperties.removeRoute(route);
+ mLinkProperties.removeRoute(getDirectConnectedRoute(mIpv4Address));
}
-
return configureDhcp(enabled, mIpv4Address, mStaticIpv4ClientAddr);
}
- private String getRandomWifiIPv4Address() {
+ private Inet4Address getRandomIPv4Address(@NonNull final byte[] rawAddr) {
+ final byte[] ipv4Addr = rawAddr;
+ ipv4Addr[3] = getRandomSanitizedByte(DOUG_ADAMS, asByte(0), asByte(1), FF);
try {
- byte[] bytes = parseNumericAddress(WIFI_HOST_IFACE_ADDR).getAddress();
- bytes[3] = getRandomSanitizedByte(DOUG_ADAMS, asByte(0), asByte(1), FF);
- return InetAddress.getByAddress(bytes).getHostAddress();
- } catch (Exception e) {
- return WIFI_HOST_IFACE_ADDR;
+ return (Inet4Address) InetAddress.getByAddress(ipv4Addr);
+ } catch (UnknownHostException e) {
+ mLog.e("Failed to construct Inet4Address from raw IPv4 addr");
+ return null;
}
}
+ private String getRandomWifiIPv4Address() {
+ final Inet4Address ipv4Addr =
+ getRandomIPv4Address(parseNumericAddress(WIFI_HOST_IFACE_ADDR).getAddress());
+ return ipv4Addr != null ? ipv4Addr.getHostAddress() : WIFI_HOST_IFACE_ADDR;
+ }
+
private boolean startIPv6() {
mInterfaceParams = mDeps.getInterfaceParams(mIfaceName);
if (mInterfaceParams == null) {
@@ -761,21 +789,43 @@
mLastIPv6UpstreamIfindex = upstreamIfindex;
}
+ 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()) {
- final ArrayList<RouteInfo> toBeRemoved =
- getLocalRoutesFor(mIfaceName, deprecatedPrefixes);
- // Remove routes from local network.
- 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);
+ removeRoutesFromLocalNetwork(getLocalRoutesFor(mIfaceName, deprecatedPrefixes));
}
// [2] Add only the routes that have not previously been added.
@@ -786,24 +836,7 @@
}
if (!addedPrefixes.isEmpty()) {
- final ArrayList<RouteInfo> toBeAdded =
- getLocalRoutesFor(mIfaceName, addedPrefixes);
- 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 IPv6 routes to local table: " + e);
- }
- } catch (ServiceSpecificException | RemoteException e) {
- mLog.e("Failed to add " + mIfaceName + " to local table: ", e);
- }
-
- for (RouteInfo route : toBeAdded) mLinkProperties.addRoute(route);
+ addRoutesToLocalNetwork(getLocalRoutesFor(mIfaceName, addedPrefixes));
}
}
}
@@ -945,6 +978,80 @@
}
}
+ // TODO: call PrivateAddressCoordinator.requestDownstreamAddress instead of this temporary
+ // logic.
+ private Inet4Address requestDownstreamAddress(@NonNull final IpPrefix currentPrefix) {
+ final int oldIndex = NCM_PREFIXES.indexOf(currentPrefix);
+ if (oldIndex == -1) {
+ mLog.e("current prefix isn't supported for NCM link: " + currentPrefix);
+ return null;
+ }
+
+ final IpPrefix newPrefix = NCM_PREFIXES.get((oldIndex + 1) % NCM_PREFIXES.size());
+ return getRandomIPv4Address(newPrefix.getRawAddress());
+ }
+
+ 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;
+ final Inet4Address srvAddr = requestDownstreamAddress(currentPrefix);
+ if (srvAddr == null) {
+ mLog.e("Fail to request a new downstream prefix");
+ return;
+ }
+ mIpv4Address = new LinkAddress(srvAddr, currentPrefix.getPrefixLength());
+
+ // 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) {
try {
int upstreamHopLimit = Integer.parseUnsignedInt(
@@ -1056,11 +1163,9 @@
}
try {
- final IpPrefix ipv4Prefix = new IpPrefix(mIpv4Address.getAddress(),
- mIpv4Address.getPrefixLength());
- NetdUtils.tetherInterface(mNetd, mIfaceName, ipv4Prefix);
+ NetdUtils.tetherInterface(mNetd, mIfaceName, PrefixUtils.asIpPrefix(mIpv4Address));
} catch (RemoteException | ServiceSpecificException | IllegalStateException e) {
- mLog.e("Error Tethering: " + e);
+ mLog.e("Error Tethering", e);
mLastError = TetheringManager.TETHER_ERROR_TETHER_IFACE_ERROR;
return;
}
@@ -1115,6 +1220,9 @@
mLastError = TetheringManager.TETHER_ERROR_INTERNAL_ERROR;
transitionTo(mInitialState);
break;
+ case CMD_NEW_PREFIX_REQUEST:
+ handleNewPrefixRequest((IpPrefix) message.obj);
+ break;
default:
return false;
}