Pass the socket mark for DNS queries to dnsmasq.

This makes tethered clients use the correct DNS servers when
tethering to non-default networks like the DUN APN.

Bug: 16357676
Change-Id: I8933b6de198a92c2aaf0291931ace8966ddba275
diff --git a/core/java/android/net/ConnectivityManager.java b/core/java/android/net/ConnectivityManager.java
index 4bfef41..3c219fd 100644
--- a/core/java/android/net/ConnectivityManager.java
+++ b/core/java/android/net/ConnectivityManager.java
@@ -685,6 +685,23 @@
     }
 
     /**
+     * Returns the {@link Network} object currently serving a given type, or
+     * null if the given type is not connected.
+     *
+     * <p>This method requires the caller to hold the permission
+     * {@link android.Manifest.permission#ACCESS_NETWORK_STATE}.
+     *
+     * @hide
+     */
+    public Network getNetworkForType(int networkType) {
+        try {
+            return mService.getNetworkForType(networkType);
+        } catch (RemoteException e) {
+            return null;
+        }
+    }
+
+    /**
      * Returns an array of all {@link Network} currently tracked by the
      * framework.
      *
diff --git a/core/java/android/net/IConnectivityManager.aidl b/core/java/android/net/IConnectivityManager.aidl
index b2fc3be..974c4cd 100644
--- a/core/java/android/net/IConnectivityManager.aidl
+++ b/core/java/android/net/IConnectivityManager.aidl
@@ -48,6 +48,7 @@
     NetworkInfo getNetworkInfo(int networkType);
     NetworkInfo getNetworkInfoForNetwork(in Network network);
     NetworkInfo[] getAllNetworkInfo();
+    Network getNetworkForType(int networkType);
     Network[] getAllNetworks();
 
     NetworkInfo getProvisioningOrActiveNetworkInfo();
diff --git a/core/java/android/os/INetworkManagementService.aidl b/core/java/android/os/INetworkManagementService.aidl
index 6d4a302..b3e28ea 100644
--- a/core/java/android/os/INetworkManagementService.aidl
+++ b/core/java/android/os/INetworkManagementService.aidl
@@ -19,6 +19,7 @@
 
 import android.net.InterfaceConfiguration;
 import android.net.INetworkManagementEventObserver;
+import android.net.Network;
 import android.net.NetworkStats;
 import android.net.RouteInfo;
 import android.net.UidRange;
@@ -164,10 +165,10 @@
     /**
      * Sets the list of DNS forwarders (in order of priority)
      */
-    void setDnsForwarders(in String[] dns);
+    void setDnsForwarders(in Network network, in String[] dns);
 
     /**
-     * Returns the list of DNS fowarders (in order of priority)
+     * Returns the list of DNS forwarders (in order of priority)
      */
     String[] getDnsForwarders();
 
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 0919f77..ef0b155 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -967,6 +967,17 @@
     }
 
     @Override
+    public Network getNetworkForType(int networkType) {
+        enforceAccessPermission();
+        final int uid = Binder.getCallingUid();
+        if (isNetworkBlocked(networkType, uid)) {
+            return null;
+        }
+        NetworkAgentInfo nai = mLegacyTypeTracker.getNetworkForType(networkType);
+        return (nai == null) ? null : nai.network;
+    }
+
+    @Override
     public Network[] getAllNetworks() {
         enforceAccessPermission();
         final ArrayList<Network> result = new ArrayList();
@@ -1724,7 +1735,7 @@
         pw.println();
 
         synchronized (this) {
-            pw.println("NetworkTranstionWakeLock is currently " +
+            pw.println("NetworkTransitionWakeLock is currently " +
                     (mNetTransitionWakeLock.isHeld() ? "" : "not ") + "held.");
             pw.println("It was last requested for "+mNetTransitionWakeLockCausedBy);
         }
diff --git a/services/core/java/com/android/server/NetworkManagementService.java b/services/core/java/com/android/server/NetworkManagementService.java
index f9b65b8..1318f66 100644
--- a/services/core/java/com/android/server/NetworkManagementService.java
+++ b/services/core/java/com/android/server/NetworkManagementService.java
@@ -44,6 +44,7 @@
 import android.net.InterfaceConfiguration;
 import android.net.IpPrefix;
 import android.net.LinkAddress;
+import android.net.Network;
 import android.net.NetworkStats;
 import android.net.NetworkUtils;
 import android.net.RouteInfo;
@@ -1200,10 +1201,12 @@
     }
 
     @Override
-    public void setDnsForwarders(String[] dns) {
+    public void setDnsForwarders(Network network, String[] dns) {
         mContext.enforceCallingOrSelfPermission(CONNECTIVITY_INTERNAL, TAG);
 
-        final Command cmd = new Command("tether", "dns", "set");
+        int netId = (network != null) ? network.netId : ConnectivityManager.NETID_UNSET;
+        final Command cmd = new Command("tether", "dns", "set", netId);
+
         for (String s : dns) {
             cmd.appendArg(NetworkUtils.numericToInetAddress(s).getHostAddress());
         }
diff --git a/services/core/java/com/android/server/connectivity/Tethering.java b/services/core/java/com/android/server/connectivity/Tethering.java
index 1fd114c..7c303ff 100644
--- a/services/core/java/com/android/server/connectivity/Tethering.java
+++ b/services/core/java/com/android/server/connectivity/Tethering.java
@@ -31,6 +31,7 @@
 import android.net.InterfaceConfiguration;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
+import android.net.Network;
 import android.net.NetworkInfo;
 import android.net.NetworkUtils;
 import android.net.RouteInfo;
@@ -56,6 +57,7 @@
 import java.net.InetAddress;
 import java.net.Inet4Address;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Iterator;
@@ -742,7 +744,7 @@
         static final int CMD_IP_FORWARDING_ENABLE_ERROR  =  7;
         // notification from the master SM that it had trouble disabling IP Forwarding
         static final int CMD_IP_FORWARDING_DISABLE_ERROR =  8;
-        // notification from the master SM that it had trouble staring tethering
+        // notification from the master SM that it had trouble starting tethering
         static final int CMD_START_TETHERING_ERROR       =  9;
         // notification from the master SM that it had trouble stopping tethering
         static final int CMD_STOP_TETHERING_ERROR        = 10;
@@ -1235,12 +1237,6 @@
                         return false;
                     }
                 }
-                try {
-                    mNMService.setDnsForwarders(mDefaultDnsServers);
-                } catch (Exception e) {
-                    transitionTo(mSetDnsForwardersErrorState);
-                    return false;
-                }
                 return true;
             }
             protected boolean turnOffMasterTetherSettings() {
@@ -1348,8 +1344,17 @@
                             }
                         }
                         try {
-                            mNMService.setDnsForwarders(dnsServers);
+                            Network network = getConnectivityManager().getNetworkForType(upType);
+                            if (network == null) {
+                                Log.e(TAG, "No Network for upstream type " + upType + "!");
+                            }
+                            if (VDBG) {
+                                Log.d(TAG, "Setting DNS forwarders: Network=" + network +
+                                       ", dnsServers=" + Arrays.toString(dnsServers));
+                            }
+                            mNMService.setDnsForwarders(network, dnsServers);
                         } catch (Exception e) {
+                            Log.e(TAG, "Setting DNS forwarders failed!");
                             transitionTo(mSetDnsForwardersErrorState);
                         }
                     }