Merge "Tethering: Skip link local addresses when enabling NAT"

1 files changed, 14 insertions, 2 deletions

diff --git a/services/java/com/android/server/NetworkManagementService.java b/services/java/com/android/server/NetworkManagementService.java
index ad7ec99775a3..e6c5422a8fc1 100644
--- a/services/java/com/android/server/NetworkManagementService.java
+++ b/services/java/com/android/server/NetworkManagementService.java
@@ -82,6 +82,7 @@ import java.net.SocketException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.StringTokenizer;
@@ -1022,6 +1023,15 @@ public class NetworkManagementService extends INetworkManagementService.Stub
         }
     }
 
+    private List<InterfaceAddress> excludeLinkLocal(List<InterfaceAddress> addresses) {
+        ArrayList<InterfaceAddress> filtered = new ArrayList<InterfaceAddress>(addresses.size());
+        for (InterfaceAddress ia : addresses) {
+            if (!ia.getAddress().isLinkLocalAddress())
+                filtered.add(ia);
+        }
+        return filtered;
+    }
+
     private void modifyNat(String action, String internalInterface, String externalInterface)
             throws SocketException {
         final Command cmd = new Command("nat", action, internalInterface, externalInterface);
@@ -1031,8 +1041,10 @@ public class NetworkManagementService extends INetworkManagementService.Stub
         if (internalNetworkInterface == null) {
             cmd.appendArg("0");
         } else {
-            Collection<InterfaceAddress> interfaceAddresses = internalNetworkInterface
-                    .getInterfaceAddresses();
+            // Don't touch link-local routes, as link-local addresses aren't routable,
+            // kernel creates link-local routes on all interfaces automatically
+            List<InterfaceAddress> interfaceAddresses = excludeLinkLocal(
+                    internalNetworkInterface.getInterfaceAddresses());
             cmd.appendArg(interfaceAddresses.size());
             for (InterfaceAddress ia : interfaceAddresses) {
                 InetAddress addr = NetworkUtils.getNetworkPart(