Fix tethering in the case of a regular upstream connection.

Fixes tethering via Ethernet, Bluetooth and WiFi (hotspot).

Tethering when the upstream has a DUN-specific APN is likely still broken
(untested).

For now, assign a fixed NetId (a hack) until we can change the framework to
create a valid NetworkAgent and all that jazz.

Bug: 15968336
Bug: 14988803
Change-Id: Idcf4d492d9329a9c87913e27be6dd835a792bea2
diff --git a/server/LocalNetwork.cpp b/server/LocalNetwork.cpp
new file mode 100644
index 0000000..ba0b21e
--- /dev/null
+++ b/server/LocalNetwork.cpp
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+#include "LocalNetwork.h"
+
+#include "RouteController.h"
+
+#define LOG_TAG "Netd"
+#include "log/log.h"
+
+LocalNetwork::LocalNetwork(unsigned netId) : Network(netId) {
+}
+
+LocalNetwork::~LocalNetwork() {
+}
+
+Network::Type LocalNetwork::getType() const {
+    return LOCAL;
+}
+
+int LocalNetwork::addInterface(const std::string& interface) {
+    if (hasInterface(interface)) {
+        return 0;
+    }
+    if (int ret = RouteController::addInterfaceToLocalNetwork(mNetId, interface.c_str())) {
+        ALOGE("failed to add interface %s to local netId %u", interface.c_str(), mNetId);
+        return ret;
+    }
+    mInterfaces.insert(interface);
+    return 0;
+}
+
+int LocalNetwork::removeInterface(const std::string& interface) {
+    if (!hasInterface(interface)) {
+        return 0;
+    }
+    if (int ret = RouteController::removeInterfaceFromLocalNetwork(mNetId, interface.c_str())) {
+        ALOGE("failed to remove interface %s from local netId %u", interface.c_str(), mNetId);
+        return ret;
+    }
+    mInterfaces.erase(interface);
+    return 0;
+}