Add forwarding methods to RoutingCoordinator

Test: RoutingCoordinatorServiceTest
      TetheringTest
Change-Id: Ic3b36ddc236e8615e7d931b6e526556bbd2dac17
diff --git a/Tethering/src/android/net/ip/IpServer.java b/Tethering/src/android/net/ip/IpServer.java
index 246e5bc..2a25a86 100644
--- a/Tethering/src/android/net/ip/IpServer.java
+++ b/Tethering/src/android/net/ip/IpServer.java
@@ -827,7 +827,38 @@
             }
         } catch (ServiceSpecificException | RemoteException e) {
             mLog.e("Failed to add " + mIfaceName + " to local table: ", e);
-            return;
+        }
+    }
+
+    private void addInterfaceForward(@NonNull final String fromIface,
+            @NonNull final String toIface) throws ServiceSpecificException, RemoteException {
+        if (null != mRoutingCoordinator.value) {
+            mRoutingCoordinator.value.addInterfaceForward(fromIface, toIface);
+        } else {
+            mNetd.tetherAddForward(fromIface, toIface);
+            mNetd.ipfwdAddInterfaceForward(fromIface, toIface);
+        }
+    }
+
+    private void removeInterfaceForward(@NonNull final String fromIface,
+            @NonNull final String toIface) {
+        if (null != mRoutingCoordinator.value) {
+            try {
+                mRoutingCoordinator.value.removeInterfaceForward(fromIface, toIface);
+            } catch (ServiceSpecificException e) {
+                mLog.e("Exception in removeInterfaceForward", e);
+            }
+        } else {
+            try {
+                mNetd.ipfwdRemoveInterfaceForward(fromIface, toIface);
+            } catch (RemoteException | ServiceSpecificException e) {
+                mLog.e("Exception in ipfwdRemoveInterfaceForward", e);
+            }
+            try {
+                mNetd.tetherRemoveForward(fromIface, toIface);
+            } catch (RemoteException | ServiceSpecificException e) {
+                mLog.e("Exception in disableNat", e);
+            }
         }
     }
 
@@ -1337,16 +1368,7 @@
             // to remove their rules, which generates errors.
             // Just do the best we can.
             mBpfCoordinator.maybeDetachProgram(mIfaceName, upstreamIface);
-            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());
-            }
+            removeInterfaceForward(mIfaceName, upstreamIface);
         }
 
         @Override
@@ -1402,10 +1424,9 @@
 
                         mBpfCoordinator.maybeAttachProgram(mIfaceName, ifname);
                         try {
-                            mNetd.tetherAddForward(mIfaceName, ifname);
-                            mNetd.ipfwdAddInterfaceForward(mIfaceName, ifname);
+                            addInterfaceForward(mIfaceName, ifname);
                         } catch (RemoteException | ServiceSpecificException e) {
-                            mLog.e("Exception enabling NAT: " + e.toString());
+                            mLog.e("Exception enabling iface forward", e);
                             cleanupUpstream();
                             mLastError = TETHER_ERROR_ENABLE_FORWARDING_ERROR;
                             transitionTo(mInitialState);
diff --git a/Tethering/tests/unit/src/android/net/ip/IpServerTest.java b/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
index fc9928d..15df3ba 100644
--- a/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
+++ b/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
@@ -321,6 +321,23 @@
         when(mTetherConfig.isBpfOffloadEnabled()).thenReturn(DEFAULT_USING_BPF_OFFLOAD);
         when(mTetherConfig.useLegacyDhcpServer()).thenReturn(false /* default value */);
 
+        // Simulate the behavior of RoutingCoordinator
+        if (null != mRoutingCoordinatorManager.value) {
+            doAnswer(it -> {
+                final String fromIface = (String) it.getArguments()[0];
+                final String toIface = (String) it.getArguments()[1];
+                mNetd.tetherAddForward(fromIface, toIface);
+                mNetd.ipfwdAddInterfaceForward(fromIface, toIface);
+                return null;
+            }).when(mRoutingCoordinatorManager.value).addInterfaceForward(any(), any());
+            doAnswer(it -> {
+                final String fromIface = (String) it.getArguments()[0];
+                final String toIface = (String) it.getArguments()[1];
+                mNetd.ipfwdRemoveInterfaceForward(fromIface, toIface);
+                mNetd.tetherRemoveForward(fromIface, toIface);
+                return null;
+            }).when(mRoutingCoordinatorManager.value).removeInterfaceForward(any(), any());
+        }
         mBpfDeps = new BpfCoordinator.Dependencies() {
                     @NonNull
                     public Handler getHandler() {