diff --git a/NetworkController.cpp b/NetworkController.cpp
new file mode 100644
index 0000000..a1f1535
--- /dev/null
+++ b/NetworkController.cpp
@@ -0,0 +1,115 @@
+/*
+ * 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 <resolv_netid.h>
+
+#define LOG_TAG "NetworkController"
+#include <cutils/log.h>
+
+#include "NetworkController.h"
+
+// Mark 1 is reserved for SecondaryTableController::PROTECT_MARK.
+NetworkController::NetworkController() : mNextFreeNetId(10) {}
+
+void NetworkController::clearNetworkPreference() {
+    android::RWLock::AutoWLock lock(mRWLock);
+    mUidMap.clear();
+    mPidMap.clear();
+}
+
+unsigned NetworkController::getDefaultNetwork() const {
+    return mDefaultNetId;
+}
+
+void NetworkController::setDefaultNetwork(unsigned netId) {
+    android::RWLock::AutoWLock lock(mRWLock);
+    mDefaultNetId = netId;
+}
+
+void NetworkController::setNetworkForPid(int pid, unsigned netId) {
+    android::RWLock::AutoWLock lock(mRWLock);
+    if (netId == 0) {
+        mPidMap.erase(pid);
+    } else {
+        mPidMap[pid] = netId;
+    }
+}
+
+bool NetworkController::setNetworkForUidRange(int uid_start, int uid_end, unsigned netId,
+        bool forward_dns) {
+    android::RWLock::AutoWLock lock(mRWLock);
+    if (uid_start > uid_end)
+        return false;
+
+    for (std::list<UidEntry>::iterator it = mUidMap.begin(); it != mUidMap.end(); ++it) {
+        if (it->uid_start > uid_end || uid_start > it->uid_end)
+            continue;
+        /* Overlapping or identical range. */
+        if (it->uid_start != uid_start || it->uid_end != uid_end) {
+            ALOGE("Overlapping but not identical uid range detected.");
+            return false;
+        }
+
+        if (netId == NETID_UNSET) {
+            mUidMap.erase(it);
+        } else {
+            it->netId = netId;
+            it->forward_dns = forward_dns;
+        }
+        return true;
+    }
+
+    mUidMap.push_back(UidEntry(uid_start, uid_end, netId, forward_dns));
+    return true;
+}
+
+unsigned NetworkController::getNetwork(int uid, unsigned requested_netId, int pid,
+        bool for_dns) const {
+    android::RWLock::AutoRLock lock(mRWLock);
+    for (std::list<UidEntry>::const_iterator it = mUidMap.begin(); it != mUidMap.end(); ++it) {
+        if (uid < it->uid_start || it->uid_end < uid)
+            continue;
+        if (for_dns && !it->forward_dns)
+            break;
+        return it->netId;
+    }
+    if (requested_netId != NETID_UNSET)
+        return requested_netId;
+    if (pid != PID_UNSPECIFIED) {
+        std::map<int, unsigned>::const_iterator it = mPidMap.find(pid);
+        if (it != mPidMap.end())
+            return it->second;
+    }
+    return mDefaultNetId;
+}
+
+unsigned NetworkController::getNetworkId(const char* interface) {
+    std::map<std::string, unsigned>::const_iterator it = mIfaceNetidMap.find(interface);
+    if (it != mIfaceNetidMap.end())
+        return it->second;
+
+    unsigned netId = mNextFreeNetId++;
+    mIfaceNetidMap[interface] = netId;
+    return netId;
+}
+
+NetworkController::UidEntry::UidEntry(
+    int start, int end, unsigned netId, bool forward_dns)
+      : uid_start(start),
+        uid_end(end),
+        netId(netId),
+        forward_dns(forward_dns) {
+}