Add m-esr52 at 52.6.0

1 files changed, 2973 insertions, 0 deletions

diff --git a/dom/system/gonk/NetworkUtils.cpp b/dom/system/gonk/NetworkUtils.cpp
new file mode 100644
index 000000000..d661368b8
--- /dev/null
+++ b/dom/system/gonk/NetworkUtils.cpp
@@ -0,0 +1,2973 @@
+/* Copyright 2012 Mozilla Foundation and Mozilla contributors
+ *
+ * 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 "NetworkUtils.h"
+
+#include "mozilla/Sprintf.h"
+#include "SystemProperty.h"
+
+#include <android/log.h>
+#include <limits>
+#include "mozilla/dom/network/NetUtils.h"
+#include "mozilla/fallible.h"
+#include "base/task.h"
+
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>  // struct addrinfo
+#include <sys/socket.h> // getaddrinfo(), freeaddrinfo()
+#include <netdb.h>
+#include <arpa/inet.h>  // inet_ntop()
+
+#define _DEBUG 0
+
+#define WARN(args...)   __android_log_print(ANDROID_LOG_WARN,  "NetworkUtils", ## args)
+#define ERROR(args...)  __android_log_print(ANDROID_LOG_ERROR,  "NetworkUtils", ## args)
+
+#if _DEBUG
+#define NU_DBG(args...)  __android_log_print(ANDROID_LOG_DEBUG, "NetworkUtils" , ## args)
+#else
+#define NU_DBG(args...)
+#endif
+
+using namespace mozilla::dom;
+using namespace mozilla::ipc;
+using mozilla::system::Property;
+
+static const char* PERSIST_SYS_USB_CONFIG_PROPERTY = "persist.sys.usb.config";
+static const char* SYS_USB_CONFIG_PROPERTY         = "sys.usb.config";
+static const char* SYS_USB_STATE_PROPERTY          = "sys.usb.state";
+
+static const char* USB_FUNCTION_RNDIS  = "rndis";
+static const char* USB_FUNCTION_ADB    = "adb";
+
+// Use this command to continue the function chain.
+static const char* DUMMY_COMMAND = "tether status";
+
+// IPV6 Tethering is not supported in AOSP, use the property to
+// identify vendor specific support in IPV6. We can remove this flag
+// once upstream Android support IPV6 in tethering.
+static const char* IPV6_TETHERING = "ro.tethering.ipv6";
+
+// Retry 20 times (2 seconds) for usb state transition.
+static const uint32_t USB_FUNCTION_RETRY_TIMES = 20;
+// Check "sys.usb.state" every 100ms.
+static const uint32_t USB_FUNCTION_RETRY_INTERVAL = 100;
+
+// 1xx - Requested action is proceeding
+static const uint32_t NETD_COMMAND_PROCEEDING   = 100;
+// 2xx - Requested action has been successfully completed
+static const uint32_t NETD_COMMAND_OKAY         = 200;
+// 4xx - The command is accepted but the requested action didn't
+// take place.
+static const uint32_t NETD_COMMAND_FAIL         = 400;
+// 5xx - The command syntax or parameters error
+static const uint32_t NETD_COMMAND_ERROR        = 500;
+// 6xx - Unsolicited broadcasts
+static const uint32_t NETD_COMMAND_UNSOLICITED  = 600;
+
+// Broadcast messages
+static const uint32_t NETD_COMMAND_INTERFACE_CHANGE     = 600;
+static const uint32_t NETD_COMMAND_BANDWIDTH_CONTROLLER = 601;
+
+static const char* INTERFACE_DELIMIT = ",";
+static const char* USB_CONFIG_DELIMIT = ",";
+static const char* NETD_MESSAGE_DELIMIT = " ";
+
+static const uint32_t BUF_SIZE = 1024;
+
+static const int32_t SUCCESS = 0;
+
+static uint32_t SDK_VERSION;
+static uint32_t SUPPORT_IPV6_TETHERING;
+
+struct IFProperties {
+  char gateway[Property::VALUE_MAX_LENGTH];
+  char dns1[Property::VALUE_MAX_LENGTH];
+  char dns2[Property::VALUE_MAX_LENGTH];
+};
+
+struct CurrentCommand {
+  CommandChain* chain;
+  CommandCallback callback;
+  char command[MAX_COMMAND_SIZE];
+};
+
+typedef Tuple3<NetdCommand*, CommandChain*, CommandCallback> QueueData;
+
+#define GET_CURRENT_NETD_COMMAND   (gCommandQueue.IsEmpty() ? nullptr : gCommandQueue[0].a)
+#define GET_CURRENT_CHAIN          (gCommandQueue.IsEmpty() ? nullptr : gCommandQueue[0].b)
+#define GET_CURRENT_CALLBACK       (gCommandQueue.IsEmpty() ? nullptr : gCommandQueue[0].c)
+#define GET_CURRENT_COMMAND        (gCommandQueue.IsEmpty() ? nullptr : gCommandQueue[0].a->mData)
+
+// A macro for native function call return value check.
+// For native function call, non-zero return value means failure.
+#define RETURN_IF_FAILED(rv) do { \
+  if (SUCCESS != rv) { \
+    return rv; \
+  } \
+} while (0);
+
+#define WARN_IF_FAILED(rv) do { \
+  if (SUCCESS != rv) { \
+    WARN("Error (%d) occurred in %s (%s:%d)", rv, __PRETTY_FUNCTION__, __FILE__, __LINE__); \
+  } \
+} while (0);
+
+static NetworkUtils* gNetworkUtils;
+static nsTArray<QueueData> gCommandQueue;
+static CurrentCommand gCurrentCommand;
+static bool gPending = false;
+static nsTArray<nsCString> gReason;
+static NetworkParams *gWifiTetheringParms = 0;
+
+static nsTArray<CommandChain*> gCommandChainQueue;
+
+const CommandFunc NetworkUtils::sWifiEnableChain[] = {
+  NetworkUtils::clearWifiTetherParms,
+  NetworkUtils::wifiFirmwareReload,
+  NetworkUtils::startAccessPointDriver,
+  NetworkUtils::setAccessPoint,
+  NetworkUtils::startSoftAP,
+  NetworkUtils::setConfig,
+  NetworkUtils::tetherInterface,
+  NetworkUtils::addInterfaceToLocalNetwork,
+  NetworkUtils::addRouteToLocalNetwork,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::tetheringStatus,
+  NetworkUtils::startTethering,
+  NetworkUtils::setDnsForwarders,
+  NetworkUtils::enableNat,
+  NetworkUtils::wifiTetheringSuccess
+};
+
+const CommandFunc NetworkUtils::sWifiDisableChain[] = {
+  NetworkUtils::clearWifiTetherParms,
+  NetworkUtils::stopSoftAP,
+  NetworkUtils::stopAccessPointDriver,
+  NetworkUtils::wifiFirmwareReload,
+  NetworkUtils::untetherInterface,
+  NetworkUtils::removeInterfaceFromLocalNetwork,
+  NetworkUtils::preTetherInterfaceList,
+  NetworkUtils::postTetherInterfaceList,
+  NetworkUtils::disableNat,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::stopTethering,
+  NetworkUtils::wifiTetheringSuccess
+};
+
+const CommandFunc NetworkUtils::sWifiFailChain[] = {
+  NetworkUtils::clearWifiTetherParms,
+  NetworkUtils::stopSoftAP,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::stopTethering
+};
+
+const CommandFunc NetworkUtils::sWifiRetryChain[] = {
+  NetworkUtils::clearWifiTetherParms,
+  NetworkUtils::stopSoftAP,
+  NetworkUtils::stopTethering,
+
+  // sWifiEnableChain:
+  NetworkUtils::wifiFirmwareReload,
+  NetworkUtils::startAccessPointDriver,
+  NetworkUtils::setAccessPoint,
+  NetworkUtils::startSoftAP,
+  NetworkUtils::setConfig,
+  NetworkUtils::tetherInterface,
+  NetworkUtils::addInterfaceToLocalNetwork,
+  NetworkUtils::addRouteToLocalNetwork,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::tetheringStatus,
+  NetworkUtils::startTethering,
+  NetworkUtils::setDnsForwarders,
+  NetworkUtils::enableNat,
+  NetworkUtils::wifiTetheringSuccess
+};
+
+const CommandFunc NetworkUtils::sWifiOperationModeChain[] = {
+  NetworkUtils::wifiFirmwareReload,
+  NetworkUtils::wifiOperationModeSuccess
+};
+
+const CommandFunc NetworkUtils::sUSBEnableChain[] = {
+  NetworkUtils::setConfig,
+  NetworkUtils::enableNat,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::tetherInterface,
+  NetworkUtils::addInterfaceToLocalNetwork,
+  NetworkUtils::addRouteToLocalNetwork,
+  NetworkUtils::tetheringStatus,
+  NetworkUtils::startTethering,
+  NetworkUtils::setDnsForwarders,
+  NetworkUtils::addUpstreamInterface,
+  NetworkUtils::usbTetheringSuccess
+};
+
+const CommandFunc NetworkUtils::sUSBDisableChain[] = {
+  NetworkUtils::untetherInterface,
+  NetworkUtils::removeInterfaceFromLocalNetwork,
+  NetworkUtils::preTetherInterfaceList,
+  NetworkUtils::postTetherInterfaceList,
+  NetworkUtils::removeUpstreamInterface,
+  NetworkUtils::disableNat,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::stopTethering,
+  NetworkUtils::usbTetheringSuccess
+};
+
+const CommandFunc NetworkUtils::sUSBFailChain[] = {
+  NetworkUtils::stopSoftAP,
+  NetworkUtils::setIpForwardingEnabled,
+  NetworkUtils::stopTethering
+};
+
+const CommandFunc NetworkUtils::sUpdateUpStreamChain[] = {
+  NetworkUtils::cleanUpStream,
+  NetworkUtils::removeUpstreamInterface,
+  NetworkUtils::createUpStream,
+  NetworkUtils::addUpstreamInterface,
+  NetworkUtils::updateUpStreamSuccess
+};
+
+const CommandFunc NetworkUtils::sStartDhcpServerChain[] = {
+  NetworkUtils::setConfig,
+  NetworkUtils::startTethering,
+  NetworkUtils::setDhcpServerSuccess
+};
+
+const CommandFunc NetworkUtils::sStopDhcpServerChain[] = {
+  NetworkUtils::stopTethering,
+  NetworkUtils::setDhcpServerSuccess
+};
+
+const CommandFunc NetworkUtils::sNetworkInterfaceEnableAlarmChain[] = {
+  NetworkUtils::enableAlarm,
+  NetworkUtils::setQuota,
+  NetworkUtils::setAlarm,
+  NetworkUtils::networkInterfaceAlarmSuccess
+};
+
+const CommandFunc NetworkUtils::sNetworkInterfaceDisableAlarmChain[] = {
+  NetworkUtils::removeQuota,
+  NetworkUtils::disableAlarm,
+  NetworkUtils::networkInterfaceAlarmSuccess
+};
+
+const CommandFunc NetworkUtils::sNetworkInterfaceSetAlarmChain[] = {
+  NetworkUtils::setAlarm,
+  NetworkUtils::networkInterfaceAlarmSuccess
+};
+
+const CommandFunc NetworkUtils::sGetInterfacesChain[] = {
+  NetworkUtils::getInterfaceList,
+  NetworkUtils::getInterfacesSuccess
+};
+
+const CommandFunc NetworkUtils::sGetInterfaceConfigChain[] = {
+  NetworkUtils::getConfig,
+  NetworkUtils::getInterfaceConfigSuccess
+};
+
+const CommandFunc NetworkUtils::sSetInterfaceConfigChain[] = {
+  NetworkUtils::setConfig,
+  NetworkUtils::setInterfaceConfigSuccess
+};
+
+const CommandFunc NetworkUtils::sTetheringInterfaceSetAlarmChain[] = {
+  NetworkUtils::setGlobalAlarm,
+  NetworkUtils::removeAlarm,
+  NetworkUtils::networkInterfaceAlarmSuccess
+};
+
+const CommandFunc NetworkUtils::sTetheringInterfaceRemoveAlarmChain[] = {
+  NetworkUtils::removeGlobalAlarm,
+  NetworkUtils::setAlarm,
+  NetworkUtils::networkInterfaceAlarmSuccess
+};
+
+const CommandFunc NetworkUtils::sTetheringGetStatusChain[] = {
+  NetworkUtils::tetheringStatus,
+  NetworkUtils::defaultAsyncSuccessHandler
+};
+
+/**
+ * Helper function to get the mask from given prefix length.
+ */
+static uint32_t makeMask(const uint32_t prefixLength)
+{
+  uint32_t mask = 0;
+  for (uint32_t i = 0; i < prefixLength; ++i) {
+    mask |= (0x80000000 >> i);
+  }
+  return ntohl(mask);
+}
+
+/**
+ * Helper function to get the network part of an ip from prefix.
+ * param ip must be in network byte order.
+ */
+static char* getNetworkAddr(const uint32_t ip, const uint32_t prefix)
+{
+  uint32_t mask = 0, subnet = 0;
+
+  mask = ~mask << (32 - prefix);
+  mask = htonl(mask);
+  subnet = ip & mask;
+
+  struct in_addr addr;
+  addr.s_addr = subnet;
+
+  return inet_ntoa(addr);
+}
+
+/**
+ * Helper function to split string by seperator, store split result as an nsTArray.
+ */
+static void split(char* str, const char* sep, nsTArray<nsCString>& result)
+{
+  char *s = strtok(str, sep);
+  while (s != nullptr) {
+    result.AppendElement(s);
+    s = strtok(nullptr, sep);
+  }
+}
+
+static void split(char* str, const char* sep, nsTArray<nsString>& result)
+{
+  char *s = strtok(str, sep);
+  while (s != nullptr) {
+    result.AppendElement(NS_ConvertUTF8toUTF16(s));
+    s = strtok(nullptr, sep);
+  }
+}
+
+/**
+ * Helper function that implement join function.
+ */
+static void join(nsTArray<nsCString>& array,
+                 const char* sep,
+                 const uint32_t maxlen,
+                 char* result)
+{
+#define CHECK_LENGTH(len, add, max)  len += add;          \
+                                     if (len > max - 1)   \
+                                       return;            \
+
+  uint32_t len = 0;
+  uint32_t seplen = strlen(sep);
+
+  if (array.Length() > 0) {
+    CHECK_LENGTH(len, strlen(array[0].get()), maxlen)
+    strcpy(result, array[0].get());
+
+    for (uint32_t i = 1; i < array.Length(); i++) {
+      CHECK_LENGTH(len, seplen, maxlen)
+      strcat(result, sep);
+
+      CHECK_LENGTH(len, strlen(array[i].get()), maxlen)
+      strcat(result, array[i].get());
+    }
+  }
+
+#undef CHECK_LEN
+}
+
+static void convertUTF8toUTF16(nsTArray<nsCString>& narrow,
+                               nsTArray<nsString>& wide,
+                               uint32_t length)
+{
+  for (uint32_t i = 0; i < length; i++) {
+    wide.AppendElement(NS_ConvertUTF8toUTF16(narrow[i].get()));
+  }
+}
+
+/**
+ * Helper function to get network interface properties from the system property table.
+ */
+static void getIFProperties(const char* ifname, IFProperties& prop)
+{
+  char key[Property::KEY_MAX_LENGTH];
+  snprintf(key, Property::KEY_MAX_LENGTH - 1, "net.%s.gw", ifname);
+  Property::Get(key, prop.gateway, "");
+  snprintf(key, Property::KEY_MAX_LENGTH - 1, "net.%s.dns1", ifname);
+  Property::Get(key, prop.dns1, "");
+  snprintf(key, Property::KEY_MAX_LENGTH - 1, "net.%s.dns2", ifname);
+  Property::Get(key, prop.dns2, "");
+}
+
+static int getIpType(const char *aIp) {
+  struct addrinfo hint, *ip_info = NULL;
+
+  memset(&hint, 0, sizeof(hint));
+  hint.ai_family = AF_UNSPEC;
+  hint.ai_flags = AI_NUMERICHOST;
+
+  if (getaddrinfo(aIp, NULL, &hint, &ip_info)) {
+    return AF_UNSPEC;
+  }
+
+  int type = ip_info->ai_family;
+  freeaddrinfo(ip_info);
+
+  return type;
+}
+
+static void postMessage(NetworkResultOptions& aResult)
+{
+  MOZ_ASSERT(gNetworkUtils);
+  MOZ_ASSERT(gNetworkUtils->getMessageCallback());
+
+  if (*(gNetworkUtils->getMessageCallback()))
+    (*(gNetworkUtils->getMessageCallback()))(aResult);
+}
+
+static void postMessage(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  MOZ_ASSERT(gNetworkUtils);
+  MOZ_ASSERT(gNetworkUtils->getMessageCallback());
+
+  aResult.mId = aOptions.mId;
+
+  if (*(gNetworkUtils->getMessageCallback()))
+    (*(gNetworkUtils->getMessageCallback()))(aResult);
+}
+
+void NetworkUtils::runNextQueuedCommandChain()
+{
+  if (gCommandChainQueue.IsEmpty()) {
+    NU_DBG("No command chain left in the queue. Done!");
+    return;
+  }
+  NU_DBG("Process the queued command chain.");
+  CommandChain* nextChain = gCommandChainQueue[0];
+  NetworkResultOptions newResult;
+  next(nextChain, false, newResult);
+}
+
+void NetworkUtils::next(CommandChain* aChain, bool aError, NetworkResultOptions& aResult)
+{
+  if (aError) {
+    ErrorCallback onError = aChain->getErrorCallback();
+    if(onError) {
+      aResult.mError = true;
+      (*onError)(aChain->getParams(), aResult);
+    }
+    delete aChain;
+    gCommandChainQueue.RemoveElementAt(0);
+    runNextQueuedCommandChain();
+    return;
+  }
+  CommandFunc f = aChain->getNextCommand();
+  if (!f) {
+    delete aChain;
+    gCommandChainQueue.RemoveElementAt(0);
+    runNextQueuedCommandChain();
+    return;
+  }
+
+  (*f)(aChain, next, aResult);
+}
+
+CommandResult::CommandResult(int32_t aResultCode)
+  : mIsPending(false)
+{
+  // This is usually not a netd command. We treat the return code
+  // typical linux convention, which uses 0 to indicate success.
+  mResult.mError = (aResultCode == SUCCESS ? false : true);
+  mResult.mResultCode = aResultCode;
+  if (aResultCode != SUCCESS) {
+    // The returned value is sometimes negative, make sure we pass a positive
+    // error number to strerror.
+    enum { STRERROR_R_BUF_SIZE = 1024, };
+    char strerrorBuf[STRERROR_R_BUF_SIZE];
+    strerror_r(abs(aResultCode), strerrorBuf, STRERROR_R_BUF_SIZE);
+    mResult.mReason = NS_ConvertUTF8toUTF16(strerrorBuf);
+  }
+}
+
+CommandResult::CommandResult(const mozilla::dom::NetworkResultOptions& aResult)
+  : mResult(aResult)
+  , mIsPending(false)
+{
+}
+
+CommandResult::CommandResult(const Pending&)
+  : mIsPending(true)
+{
+}
+
+bool CommandResult::isPending() const
+{
+  return mIsPending;
+}
+
+/**
+ * Send command to netd.
+ */
+void NetworkUtils::nextNetdCommand()
+{
+  if (gCommandQueue.IsEmpty() || gPending) {
+    return;
+  }
+
+  gCurrentCommand.chain = GET_CURRENT_CHAIN;
+  gCurrentCommand.callback = GET_CURRENT_CALLBACK;
+  snprintf(gCurrentCommand.command, MAX_COMMAND_SIZE - 1, "%s", GET_CURRENT_COMMAND);
+
+  NU_DBG("Sending \'%s\' command to netd.", gCurrentCommand.command);
+  SendNetdCommand(GET_CURRENT_NETD_COMMAND);
+
+  gCommandQueue.RemoveElementAt(0);
+  gPending = true;
+}
+
+/**
+ * Composite NetdCommand sent to netd
+ *
+ * @param aCommand  Command sent to netd to execute.
+ * @param aChain    Store command chain data, ex. command parameter.
+ * @param aCallback Callback function to be executed when the result of
+ *                  this command is returned from netd.
+ */
+void NetworkUtils::doCommand(const char* aCommand, CommandChain* aChain, CommandCallback aCallback)
+{
+  NU_DBG("Preparing to send \'%s\' command...", aCommand);
+
+  NetdCommand* netdCommand = new NetdCommand();
+
+  // Android JB version adds sequence number to netd command.
+  if (SDK_VERSION >= 16) {
+    snprintf((char*)netdCommand->mData, MAX_COMMAND_SIZE - 1, "0 %s", aCommand);
+  } else {
+    snprintf((char*)netdCommand->mData, MAX_COMMAND_SIZE - 1, "%s", aCommand);
+  }
+  netdCommand->mSize = strlen((char*)netdCommand->mData) + 1;
+
+  gCommandQueue.AppendElement(QueueData(netdCommand, aChain, aCallback));
+
+  nextNetdCommand();
+}
+
+/*
+ * Netd command function
+ */
+#define GET_CHAR(prop) NS_ConvertUTF16toUTF8(aChain->getParams().prop).get()
+#define GET_FIELD(prop) aChain->getParams().prop
+
+void NetworkUtils::wifiFirmwareReload(CommandChain* aChain,
+                                      CommandCallback aCallback,
+                                      NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "softap fwreload %s %s", GET_CHAR(mIfname), GET_CHAR(mMode));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::startAccessPointDriver(CommandChain* aChain,
+                                          CommandCallback aCallback,
+                                          NetworkResultOptions& aResult)
+{
+  // Skip the command for sdk version >= 16.
+  if (SDK_VERSION >= 16) {
+    aResult.mResultCode = 0;
+    aResult.mResultReason = NS_ConvertUTF8toUTF16("");
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "softap start %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::stopAccessPointDriver(CommandChain* aChain,
+                                         CommandCallback aCallback,
+                                         NetworkResultOptions& aResult)
+{
+  // Skip the command for sdk version >= 16.
+  if (SDK_VERSION >= 16) {
+    aResult.mResultCode = 0;
+    aResult.mResultReason = NS_ConvertUTF8toUTF16("");
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "softap stop %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+/**
+ * Command format for sdk version < 16
+ *   Arguments:
+ *     argv[2] - wlan interface
+ *     argv[3] - SSID
+ *     argv[4] - Security
+ *     argv[5] - Key
+ *     argv[6] - Channel
+ *     argv[7] - Preamble
+ *     argv[8] - Max SCB
+ *
+ * Command format for sdk version >= 16
+ *   Arguments:
+ *     argv[2] - wlan interface
+ *     argv[3] - SSID
+ *     argv[4] - Security
+ *     argv[5] - Key
+ *
+ * Command format for sdk version >= 18
+ *   Arguments:
+ *      argv[2] - wlan interface
+ *      argv[3] - SSID
+ *      argv[4] - Broadcast/Hidden
+ *      argv[5] - Channel
+ *      argv[6] - Security
+ *      argv[7] - Key
+ */
+void NetworkUtils::setAccessPoint(CommandChain* aChain,
+                                  CommandCallback aCallback,
+                                  NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  nsCString ssid(GET_CHAR(mSsid));
+  nsCString key(GET_CHAR(mKey));
+
+  escapeQuote(ssid);
+  escapeQuote(key);
+
+  if (SDK_VERSION >= 19) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "softap set %s \"%s\" broadcast 6 %s \"%s\"",
+             GET_CHAR(mIfname),
+             ssid.get(),
+             GET_CHAR(mSecurity),
+             key.get());
+  } else if (SDK_VERSION >= 16) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "softap set %s \"%s\" %s \"%s\"",
+             GET_CHAR(mIfname),
+             ssid.get(),
+             GET_CHAR(mSecurity),
+             key.get());
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "softap set %s %s \"%s\" %s \"%s\" 6 0 8",
+             GET_CHAR(mIfname),
+             GET_CHAR(mWifictrlinterfacename),
+             ssid.get(),
+             GET_CHAR(mSecurity),
+             key.get());
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::cleanUpStream(CommandChain* aChain,
+                                 CommandCallback aCallback,
+                                 NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "nat disable %s %s 0", GET_CHAR(mPreInternalIfname), GET_CHAR(mPreExternalIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::createUpStream(CommandChain* aChain,
+                                  CommandCallback aCallback,
+                                  NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "nat enable %s %s 0", GET_CHAR(mCurInternalIfname), GET_CHAR(mCurExternalIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::startSoftAP(CommandChain* aChain,
+                               CommandCallback aCallback,
+                               NetworkResultOptions& aResult)
+{
+  const char* command= "softap startap";
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::stopSoftAP(CommandChain* aChain,
+                              CommandCallback aCallback,
+                              NetworkResultOptions& aResult)
+{
+  const char* command= "softap stopap";
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::clearWifiTetherParms(CommandChain* aChain,
+                                        CommandCallback aCallback,
+                                        NetworkResultOptions& aResult)
+{
+  delete gWifiTetheringParms;
+  gWifiTetheringParms = 0;
+  next(aChain, false, aResult);
+}
+
+void NetworkUtils::enableAlarm(CommandChain* aChain,
+                               CommandCallback aCallback,
+                               NetworkResultOptions& aResult)
+{
+  const char* command= "bandwidth enable";
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::disableAlarm(CommandChain* aChain,
+                                CommandCallback aCallback,
+                                NetworkResultOptions& aResult)
+{
+  const char* command= "bandwidth disable";
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setQuota(CommandChain* aChain,
+                            CommandCallback aCallback,
+                            NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "bandwidth setiquota %s % " PRId64, GET_CHAR(mIfname), INT64_MAX);
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeQuota(CommandChain* aChain,
+                               CommandCallback aCallback,
+                               NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "bandwidth removeiquota %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setAlarm(CommandChain* aChain,
+                            CommandCallback aCallback,
+                            NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "bandwidth setinterfacealert %s %lld",
+           GET_CHAR(mIfname), GET_FIELD(mThreshold));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeAlarm(CommandChain* aChain,
+                            CommandCallback aCallback,
+                            NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "bandwidth removeinterfacealert %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setGlobalAlarm(CommandChain* aChain,
+                                  CommandCallback aCallback,
+                                  NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  snprintf(command, MAX_COMMAND_SIZE - 1, "bandwidth setglobalalert %lld", GET_FIELD(mThreshold));
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeGlobalAlarm(CommandChain* aChain,
+                                     CommandCallback aCallback,
+                                     NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  snprintf(command, MAX_COMMAND_SIZE - 1, "bandwidth removeglobalalert");
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::tetherInterface(CommandChain* aChain,
+                                   CommandCallback aCallback,
+                                   NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "tether interface add %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::addInterfaceToLocalNetwork(CommandChain* aChain,
+                                              CommandCallback aCallback,
+                                              NetworkResultOptions& aResult)
+{
+  // Skip the command for sdk version < 20.
+  if (SDK_VERSION < 20) {
+    aResult.mResultCode = 0;
+    aResult.mResultReason = NS_ConvertUTF8toUTF16("");
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network interface add local %s",
+           GET_CHAR(mInternalIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::addRouteToLocalNetwork(CommandChain* aChain,
+                                          CommandCallback aCallback,
+                                          NetworkResultOptions& aResult)
+{
+  // Skip the command for sdk version < 20.
+  if (SDK_VERSION < 20) {
+    aResult.mResultCode = 0;
+    aResult.mResultReason = NS_ConvertUTF8toUTF16("");
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  uint32_t prefix = atoi(GET_CHAR(mPrefix));
+  uint32_t ip = inet_addr(GET_CHAR(mIp));
+  char* networkAddr = getNetworkAddr(ip, prefix);
+
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network route add local %s %s/%s",
+           GET_CHAR(mInternalIfname), networkAddr, GET_CHAR(mPrefix));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::preTetherInterfaceList(CommandChain* aChain,
+                                          CommandCallback aCallback,
+                                          NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  if (SDK_VERSION >= 16) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "tether interface list");
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "tether interface list 0");
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::postTetherInterfaceList(CommandChain* aChain,
+                                           CommandCallback aCallback,
+                                           NetworkResultOptions& aResult)
+{
+  // Send the dummy command to continue the function chain.
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "%s", DUMMY_COMMAND);
+
+  char buf[BUF_SIZE];
+  NS_ConvertUTF16toUTF8 reason(aResult.mResultReason);
+
+  size_t length = reason.Length() + 1 < BUF_SIZE ? reason.Length() + 1 : BUF_SIZE;
+  memcpy(buf, reason.get(), length);
+  split(buf, INTERFACE_DELIMIT, GET_FIELD(mInterfaceList));
+
+  doCommand(command, aChain, aCallback);
+}
+
+bool isCommandChainIPv6(CommandChain* aChain, const char *externalInterface) {
+  // Check by gateway address
+  if (getIpType(GET_CHAR(mGateway)) == AF_INET6) {
+    return true;
+  }
+
+  uint32_t length = GET_FIELD(mGateways).Length();
+  for (uint32_t i = 0; i < length; i++) {
+    NS_ConvertUTF16toUTF8 autoGateway(GET_FIELD(mGateways)[i]);
+    if(getIpType(autoGateway.get()) == AF_INET6) {
+      return true;
+    }
+  }
+
+  // Check by external inteface address
+  FILE *file = fopen("/proc/net/if_inet6", "r");
+  if (!file) {
+    return false;
+  }
+
+  bool isIPv6 = false;
+  char interface[32];
+  while(fscanf(file, "%*s %*s %*s %*s %*s %32s", interface)) {
+    if (strcmp(interface, externalInterface) == 0) {
+      isIPv6 = true;
+      break;
+    }
+  }
+
+  fclose(file);
+  return isIPv6;
+}
+
+void NetworkUtils::addUpstreamInterface(CommandChain* aChain,
+                                        CommandCallback aCallback,
+                                        NetworkResultOptions& aResult)
+{
+  nsCString interface(GET_CHAR(mExternalIfname));
+  if (!interface.get()[0]) {
+    interface = GET_CHAR(mCurExternalIfname);
+  }
+
+  if (SUPPORT_IPV6_TETHERING == 0 || !isCommandChainIPv6(aChain, interface.get())) {
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "tether interface add_upstream %s",
+           interface.get());
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeUpstreamInterface(CommandChain* aChain,
+                                           CommandCallback aCallback,
+                                           NetworkResultOptions& aResult)
+{
+  nsCString interface(GET_CHAR(mExternalIfname));
+  if (!interface.get()[0]) {
+    interface = GET_CHAR(mPreExternalIfname);
+  }
+
+  if (SUPPORT_IPV6_TETHERING == 0 || !isCommandChainIPv6(aChain, interface.get())) {
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "tether interface remove_upstream %s",
+           interface.get());
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setIpForwardingEnabled(CommandChain* aChain,
+                                          CommandCallback aCallback,
+                                          NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  if (GET_FIELD(mEnable)) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "ipfwd enable");
+  } else {
+    // Don't disable ip forwarding because others interface still need it.
+    // Send the dummy command to continue the function chain.
+    if (GET_FIELD(mInterfaceList).Length() > 1) {
+      snprintf(command, MAX_COMMAND_SIZE - 1, "%s", DUMMY_COMMAND);
+    } else {
+      snprintf(command, MAX_COMMAND_SIZE - 1, "ipfwd disable");
+    }
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::tetheringStatus(CommandChain* aChain,
+                                   CommandCallback aCallback,
+                                   NetworkResultOptions& aResult)
+{
+  const char* command= "tether status";
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::stopTethering(CommandChain* aChain,
+                                 CommandCallback aCallback,
+                                 NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  // Don't stop tethering because others interface still need it.
+  // Send the dummy to continue the function chain.
+  if (GET_FIELD(mInterfaceList).Length() > 1) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "%s", DUMMY_COMMAND);
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "tether stop");
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::startTethering(CommandChain* aChain,
+                                  CommandCallback aCallback,
+                                  NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  // We don't need to start tethering again.
+  // Send the dummy command to continue the function chain.
+  if (aResult.mResultReason.Find("started") != kNotFound) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "%s", DUMMY_COMMAND);
+  } else {
+    // If usbStartIp/usbEndIp is not valid, don't append them since
+    // the trailing white spaces will be parsed to extra empty args
+    // See: http://androidxref.com/4.3_r2.1/xref/system/core/libsysutils/src/FrameworkListener.cpp#78
+    if (!GET_FIELD(mUsbStartIp).IsEmpty() && !GET_FIELD(mUsbEndIp).IsEmpty()) {
+      snprintf(command, MAX_COMMAND_SIZE - 1, "tether start %s %s %s %s",
+               GET_CHAR(mWifiStartIp), GET_CHAR(mWifiEndIp),
+               GET_CHAR(mUsbStartIp),  GET_CHAR(mUsbEndIp));
+    } else {
+      snprintf(command, MAX_COMMAND_SIZE - 1, "tether start %s %s",
+               GET_CHAR(mWifiStartIp), GET_CHAR(mWifiEndIp));
+    }
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::untetherInterface(CommandChain* aChain,
+                                     CommandCallback aCallback,
+                                     NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "tether interface remove %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeInterfaceFromLocalNetwork(CommandChain* aChain,
+                                                   CommandCallback aCallback,
+                                                   NetworkResultOptions& aResult)
+{
+  // Skip the command for sdk version < 20.
+  if (SDK_VERSION < 20) {
+    aResult.mResultCode = 0;
+    aResult.mResultReason = NS_ConvertUTF8toUTF16("");
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network interface remove local %s",
+           GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setDnsForwarders(CommandChain* aChain,
+                                    CommandCallback aCallback,
+                                    NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  if (SDK_VERSION >= 20) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "tether dns set %d %s %s",
+             GET_FIELD(mNetId), GET_CHAR(mDns1), GET_CHAR(mDns2));
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "tether dns set %s %s",
+             GET_CHAR(mDns1), GET_CHAR(mDns2));
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::enableNat(CommandChain* aChain,
+                             CommandCallback aCallback,
+                             NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  if (!GET_FIELD(mIp).IsEmpty() && !GET_FIELD(mPrefix).IsEmpty()) {
+    uint32_t prefix = atoi(GET_CHAR(mPrefix));
+    uint32_t ip = inet_addr(GET_CHAR(mIp));
+    char* networkAddr = getNetworkAddr(ip, prefix);
+
+    // address/prefix will only take effect when secondary routing table exists.
+    snprintf(command, MAX_COMMAND_SIZE - 1, "nat enable %s %s 1 %s/%s",
+             GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname), networkAddr,
+             GET_CHAR(mPrefix));
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "nat enable %s %s 0",
+             GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname));
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::disableNat(CommandChain* aChain,
+                              CommandCallback aCallback,
+                              NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  if (!GET_FIELD(mIp).IsEmpty() && !GET_FIELD(mPrefix).IsEmpty()) {
+    uint32_t prefix = atoi(GET_CHAR(mPrefix));
+    uint32_t ip = inet_addr(GET_CHAR(mIp));
+    char* networkAddr = getNetworkAddr(ip, prefix);
+
+    snprintf(command, MAX_COMMAND_SIZE - 1, "nat disable %s %s 1 %s/%s",
+             GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname), networkAddr,
+             GET_CHAR(mPrefix));
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "nat disable %s %s 0",
+             GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname));
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setDefaultInterface(CommandChain* aChain,
+                                       CommandCallback aCallback,
+                                       NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "resolver setdefaultif %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeDefaultRoute(CommandChain* aChain,
+                                      CommandCallback aCallback,
+                                      NetworkResultOptions& aResult)
+{
+  if (GET_FIELD(mLoopIndex) >= GET_FIELD(mGateways).Length()) {
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  nsTArray<nsString>& gateways = GET_FIELD(mGateways);
+  NS_ConvertUTF16toUTF8 autoGateway(gateways[GET_FIELD(mLoopIndex)]);
+
+  int type = getIpType(autoGateway.get());
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network route remove %d %s %s/0 %s",
+           GET_FIELD(mNetId), GET_CHAR(mIfname),
+           type == AF_INET6 ? "::" : "0.0.0.0", autoGateway.get());
+
+  struct MyCallback {
+    static void callback(CommandCallback::CallbackType aOriginalCallback,
+                         CommandChain* aChain,
+                         bool aError,
+                         mozilla::dom::NetworkResultOptions& aResult)
+    {
+      NS_ConvertUTF16toUTF8 reason(aResult.mResultReason);
+      NU_DBG("removeDefaultRoute's reason: %s", reason.get());
+      if (aError && !reason.EqualsASCII("removeRoute() failed (No such process)")) {
+        return aOriginalCallback(aChain, aError, aResult);
+      }
+
+      GET_FIELD(mLoopIndex)++;
+      return removeDefaultRoute(aChain, aOriginalCallback, aResult);
+    }
+  };
+
+  CommandCallback wrappedCallback(MyCallback::callback, aCallback);
+  doCommand(command, aChain, wrappedCallback);
+}
+
+void NetworkUtils::setInterfaceDns(CommandChain* aChain,
+                                   CommandCallback aCallback,
+                                   NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  int written;
+
+  if (SDK_VERSION >= 20) {
+    written = SprintfLiteral(command, "resolver setnetdns %d %s",
+                             GET_FIELD(mNetId), GET_CHAR(mDomain));
+  } else {
+    written = SprintfLiteral(command, "resolver setifdns %s %s",
+                             GET_CHAR(mIfname), GET_CHAR(mDomain));
+  }
+
+  nsTArray<nsString>& dnses = GET_FIELD(mDnses);
+  uint32_t length = dnses.Length();
+
+  for (uint32_t i = 0; i < length; i++) {
+    NS_ConvertUTF16toUTF8 autoDns(dnses[i]);
+
+    int ret = snprintf(command + written, sizeof(command) - written, " %s", autoDns.get());
+    if (ret <= 1) {
+      command[written] = '\0';
+      continue;
+    }
+
+    if (((size_t)ret + written) >= sizeof(command)) {
+      command[written] = '\0';
+      break;
+    }
+
+    written += ret;
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::getInterfaceList(CommandChain* aChain,
+                                    CommandCallback aCallback,
+                                    NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "interface list");
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::getConfig(CommandChain* aChain,
+                             CommandCallback aCallback,
+                             NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "interface getcfg %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setConfig(CommandChain* aChain,
+                             CommandCallback aCallback,
+                             NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  if (SDK_VERSION >= 16) {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "interface setcfg %s %s %s %s",
+                      GET_CHAR(mIfname),
+                      GET_CHAR(mIp),
+                      GET_CHAR(mPrefix),
+                      GET_CHAR(mLink));
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1, "interface setcfg %s %s %s [%s]",
+                      GET_CHAR(mIfname),
+                      GET_CHAR(mIp),
+                      GET_CHAR(mPrefix),
+                      GET_CHAR(mLink));
+  }
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::clearAddrForInterface(CommandChain* aChain,
+                                         CommandCallback aCallback,
+                                         NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "interface clearaddrs %s", GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::createNetwork(CommandChain* aChain,
+                                 CommandCallback aCallback,
+                                 NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network create %d", GET_FIELD(mNetId));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::destroyNetwork(CommandChain* aChain,
+                                  CommandCallback aCallback,
+                                  NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network destroy %d", GET_FIELD(mNetId));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::addInterfaceToNetwork(CommandChain* aChain,
+                                         CommandCallback aCallback,
+                                         NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network interface add %d %s",
+           GET_FIELD(mNetId), GET_CHAR(mIfname));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::addRouteToInterface(CommandChain* aChain,
+                                       CommandCallback aCallback,
+                                       NetworkResultOptions& aResult)
+{
+  struct MyCallback {
+    static void callback(CommandCallback::CallbackType aOriginalCallback,
+                         CommandChain* aChain,
+                         bool aError,
+                         mozilla::dom::NetworkResultOptions& aResult)
+    {
+      NS_ConvertUTF16toUTF8 reason(aResult.mResultReason);
+      NU_DBG("addRouteToInterface's reason: %s", reason.get());
+      if (aError && reason.EqualsASCII("addRoute() failed (File exists)")) {
+        NU_DBG("Ignore \"File exists\" error when adding host route.");
+        return aOriginalCallback(aChain, false, aResult);
+      }
+      aOriginalCallback(aChain, aError, aResult);
+    }
+  };
+
+  CommandCallback wrappedCallback(MyCallback::callback, aCallback);
+  modifyRouteOnInterface(aChain, wrappedCallback, aResult, true);
+}
+
+void NetworkUtils::removeRouteFromInterface(CommandChain* aChain,
+                                            CommandCallback aCallback,
+                                            NetworkResultOptions& aResult)
+{
+  modifyRouteOnInterface(aChain, aCallback, aResult, false);
+}
+
+void NetworkUtils::modifyRouteOnInterface(CommandChain* aChain,
+                                          CommandCallback aCallback,
+                                          NetworkResultOptions& aResult,
+                                          bool aDoAdd)
+{
+  char command[MAX_COMMAND_SIZE];
+
+  // AOSP adds host route to its interface table but it doesn't work for
+  // B2G because we cannot set fwmark per application. So, we add
+  // all host routes to legacy_system table except scope link route.
+
+  nsCString ipOrSubnetIp = NS_ConvertUTF16toUTF8(GET_FIELD(mIp));
+  nsCString gatewayOrEmpty;
+  const char* legacyOrEmpty = "legacy 0 "; // Add to legacy by default.
+  if (GET_FIELD(mGateway).IsEmpty()) {
+    ipOrSubnetIp = getSubnetIp(ipOrSubnetIp, GET_FIELD(mPrefixLength));
+    legacyOrEmpty = ""; // Add to interface table for scope link route.
+  } else {
+    gatewayOrEmpty = nsCString(" ") + NS_ConvertUTF16toUTF8(GET_FIELD(mGateway));
+  }
+
+  const char* action = aDoAdd ? "add" : "remove";
+
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network route %s%s %d %s %s/%d%s",
+           legacyOrEmpty, action,
+           GET_FIELD(mNetId), GET_CHAR(mIfname), ipOrSubnetIp.get(),
+           GET_FIELD(mPrefixLength), gatewayOrEmpty.get());
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::addDefaultRouteToNetwork(CommandChain* aChain,
+                                            CommandCallback aCallback,
+                                            NetworkResultOptions& aResult)
+{
+  if (GET_FIELD(mLoopIndex) >= GET_FIELD(mGateways).Length()) {
+    aCallback(aChain, false, aResult);
+    return;
+  }
+
+  char command[MAX_COMMAND_SIZE];
+  nsTArray<nsString>& gateways = GET_FIELD(mGateways);
+  NS_ConvertUTF16toUTF8 autoGateway(gateways[GET_FIELD(mLoopIndex)]);
+
+  int type = getIpType(autoGateway.get());
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network route add %d %s %s/0 %s",
+           GET_FIELD(mNetId), GET_CHAR(mIfname),
+           type == AF_INET6 ? "::" : "0.0.0.0", autoGateway.get());
+
+  struct MyCallback {
+    static void callback(CommandCallback::CallbackType aOriginalCallback,
+                         CommandChain* aChain,
+                         bool aError,
+                         mozilla::dom::NetworkResultOptions& aResult)
+    {
+      NS_ConvertUTF16toUTF8 reason(aResult.mResultReason);
+      NU_DBG("addDefaultRouteToNetwork's reason: %s", reason.get());
+      if (aError && !reason.EqualsASCII("addRoute() failed (File exists)")) {
+        return aOriginalCallback(aChain, aError, aResult);
+      }
+
+      GET_FIELD(mLoopIndex)++;
+      return addDefaultRouteToNetwork(aChain, aOriginalCallback, aResult);
+    }
+  };
+
+  CommandCallback wrappedCallback(MyCallback::callback, aCallback);
+  doCommand(command, aChain, wrappedCallback);
+}
+
+void NetworkUtils::setDefaultNetwork(CommandChain* aChain,
+                                     CommandCallback aCallback,
+                                     NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "network default set %d", GET_FIELD(mNetId));
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::addRouteToSecondaryTable(CommandChain* aChain,
+                                            CommandCallback aCallback,
+                                            NetworkResultOptions& aResult) {
+
+  char command[MAX_COMMAND_SIZE];
+
+  if (SDK_VERSION >= 20) {
+    snprintf(command, MAX_COMMAND_SIZE - 1,
+             "network route add %d %s %s/%s %s",
+             GET_FIELD(mNetId),
+             GET_CHAR(mIfname),
+             GET_CHAR(mIp),
+             GET_CHAR(mPrefix),
+             GET_CHAR(mGateway));
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1,
+             "interface route add %s secondary %s %s %s",
+             GET_CHAR(mIfname),
+             GET_CHAR(mIp),
+             GET_CHAR(mPrefix),
+             GET_CHAR(mGateway));
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::removeRouteFromSecondaryTable(CommandChain* aChain,
+                                                 CommandCallback aCallback,
+                                                 NetworkResultOptions& aResult) {
+  char command[MAX_COMMAND_SIZE];
+
+  if (SDK_VERSION >= 20) {
+    snprintf(command, MAX_COMMAND_SIZE - 1,
+             "network route remove %d %s %s/%s %s",
+             GET_FIELD(mNetId),
+             GET_CHAR(mIfname),
+             GET_CHAR(mIp),
+             GET_CHAR(mPrefix),
+             GET_CHAR(mGateway));
+  } else {
+    snprintf(command, MAX_COMMAND_SIZE - 1,
+             "interface route remove %s secondary %s %s %s",
+             GET_CHAR(mIfname),
+             GET_CHAR(mIp),
+             GET_CHAR(mPrefix),
+             GET_CHAR(mGateway));
+  }
+
+  doCommand(command, aChain, aCallback);
+}
+
+void NetworkUtils::setIpv6Enabled(CommandChain* aChain,
+                                  CommandCallback aCallback,
+                                  NetworkResultOptions& aResult,
+                                  bool aEnabled)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "interface ipv6 %s %s",
+           GET_CHAR(mIfname), aEnabled ? "enable" : "disable");
+
+  struct MyCallback {
+    static void callback(CommandCallback::CallbackType aOriginalCallback,
+                         CommandChain* aChain,
+                         bool aError,
+                         mozilla::dom::NetworkResultOptions& aResult)
+    {
+      aOriginalCallback(aChain, false, aResult);
+    }
+  };
+
+  CommandCallback wrappedCallback(MyCallback::callback, aCallback);
+  doCommand(command, aChain, wrappedCallback);
+}
+
+void NetworkUtils::enableIpv6(CommandChain* aChain,
+                              CommandCallback aCallback,
+                              NetworkResultOptions& aResult)
+{
+  setIpv6Enabled(aChain, aCallback, aResult, true);
+}
+
+void NetworkUtils::disableIpv6(CommandChain* aChain,
+                               CommandCallback aCallback,
+                               NetworkResultOptions& aResult)
+{
+  setIpv6Enabled(aChain, aCallback, aResult, false);
+}
+
+void NetworkUtils::setMtu(CommandChain* aChain,
+                          CommandCallback aCallback,
+                          NetworkResultOptions& aResult)
+{
+  char command[MAX_COMMAND_SIZE];
+  snprintf(command, MAX_COMMAND_SIZE - 1, "interface setmtu %s %ld",
+           GET_CHAR(mIfname), GET_FIELD(mMtu));
+
+  doCommand(command, aChain, aCallback);
+}
+
+#undef GET_CHAR
+#undef GET_FIELD
+
+/*
+ * Netd command success/fail function
+ */
+#define ASSIGN_FIELD(prop)  aResult.prop = aChain->getParams().prop;
+#define ASSIGN_FIELD_VALUE(prop, value)  aResult.prop = value;
+
+template<size_t N>
+void NetworkUtils::runChain(const NetworkParams& aParams,
+                            const CommandFunc (&aCmds)[N],
+                            ErrorCallback aError)
+{
+  CommandChain* chain = new CommandChain(aParams, aCmds, N, aError);
+  gCommandChainQueue.AppendElement(chain);
+
+  if (gCommandChainQueue.Length() > 1) {
+    NU_DBG("%d command chains are queued. Wait!", gCommandChainQueue.Length());
+    return;
+  }
+
+  NetworkResultOptions result;
+  NetworkUtils::next(gCommandChainQueue[0], false, result);
+}
+
+// Called to clean up the command chain and process the queued command chain if any.
+void NetworkUtils::finalizeSuccess(CommandChain* aChain,
+                                   NetworkResultOptions& aResult)
+{
+  next(aChain, false, aResult);
+}
+
+void NetworkUtils::wifiTetheringFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  // Notify the main thread.
+  postMessage(aOptions, aResult);
+
+  // If one of the stages fails, we try roll back to ensure
+  // we don't leave the network systems in limbo.
+  ASSIGN_FIELD_VALUE(mEnable, false)
+  runChain(aOptions, sWifiFailChain, nullptr);
+}
+
+void NetworkUtils::wifiTetheringSuccess(CommandChain* aChain,
+                                        CommandCallback aCallback,
+                                        NetworkResultOptions& aResult)
+{
+  ASSIGN_FIELD(mEnable)
+
+  if (aChain->getParams().mEnable) {
+    MOZ_ASSERT(!gWifiTetheringParms);
+    gWifiTetheringParms = new NetworkParams(aChain->getParams());
+  }
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::usbTetheringFail(NetworkParams& aOptions,
+                                    NetworkResultOptions& aResult)
+{
+  // Notify the main thread.
+  postMessage(aOptions, aResult);
+  // Try to roll back to ensure
+  // we don't leave the network systems in limbo.
+  // This parameter is used to disable ipforwarding.
+  {
+    aOptions.mEnable = false;
+    runChain(aOptions, sUSBFailChain, nullptr);
+  }
+
+  // Disable usb rndis function.
+  {
+    NetworkParams options;
+    options.mEnable = false;
+    options.mReport = false;
+    gNetworkUtils->enableUsbRndis(options);
+  }
+}
+
+void NetworkUtils::usbTetheringSuccess(CommandChain* aChain,
+                                       CommandCallback aCallback,
+                                       NetworkResultOptions& aResult)
+{
+  ASSIGN_FIELD(mEnable)
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::networkInterfaceAlarmFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::networkInterfaceAlarmSuccess(CommandChain* aChain,
+                                                CommandCallback aCallback,
+                                                NetworkResultOptions& aResult)
+{
+  // TODO : error is not used , and it is conflict with boolean type error.
+  // params.error = parseFloat(params.resultReason);
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::updateUpStreamFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::updateUpStreamSuccess(CommandChain* aChain,
+                                         CommandCallback aCallback,
+                                         NetworkResultOptions& aResult)
+{
+  ASSIGN_FIELD(mCurExternalIfname)
+  ASSIGN_FIELD(mCurInternalIfname)
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::setDhcpServerFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  aResult.mSuccess = false;
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::setDhcpServerSuccess(CommandChain* aChain, CommandCallback aCallback, NetworkResultOptions& aResult)
+{
+  aResult.mSuccess = true;
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::wifiOperationModeFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::wifiOperationModeSuccess(CommandChain* aChain,
+                                            CommandCallback aCallback,
+                                            NetworkResultOptions& aResult)
+{
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::setDnsFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::defaultAsyncSuccessHandler(CommandChain* aChain,
+                                              CommandCallback aCallback,
+                                              NetworkResultOptions& aResult)
+{
+  NU_DBG("defaultAsyncSuccessHandler");
+  aResult.mRet = true;
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::defaultAsyncFailureHandler(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  aResult.mRet = false;
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::getInterfacesFail(NetworkParams& aOptions, NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::getInterfacesSuccess(CommandChain* aChain,
+                                        CommandCallback aCallback,
+                                        NetworkResultOptions& aResult)
+{
+  char buf[BUF_SIZE];
+  NS_ConvertUTF16toUTF8 reason(aResult.mResultReason);
+  memcpy(buf, reason.get(), strlen(reason.get()));
+
+  nsTArray<nsCString> result;
+  split(buf, INTERFACE_DELIMIT, result);
+
+  nsTArray<nsString> interfaceList;
+  uint32_t length = result.Length();
+  convertUTF8toUTF16(result, interfaceList, length);
+
+  aResult.mInterfaceList.Construct();
+  for (uint32_t i = 0; i < length; i++) {
+    aResult.mInterfaceList.Value().AppendElement(interfaceList[i], fallible_t());
+  }
+
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::getInterfaceConfigFail(NetworkParams& aOptions,
+                                          NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::getInterfaceConfigSuccess(CommandChain* aChain,
+                                             CommandCallback aCallback,
+                                             NetworkResultOptions& aResult)
+{
+  char buf[BUF_SIZE];
+  NS_ConvertUTF16toUTF8 reason(aResult.mResultReason);
+  memcpy(buf, reason.get(), strlen(reason.get()));
+
+  nsTArray<nsCString> result;
+  split(buf, NETD_MESSAGE_DELIMIT, result);
+
+  ASSIGN_FIELD_VALUE(mMacAddr, NS_ConvertUTF8toUTF16(result[0]))
+  ASSIGN_FIELD_VALUE(mIpAddr, NS_ConvertUTF8toUTF16(result[1]))
+  ASSIGN_FIELD_VALUE(mPrefixLength, atol(result[2].get()))
+
+  if (result[3].Find("up")) {
+    ASSIGN_FIELD_VALUE(mFlag, NS_ConvertUTF8toUTF16("up"))
+  } else {
+    ASSIGN_FIELD_VALUE(mFlag, NS_ConvertUTF8toUTF16("down"))
+  }
+
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+void NetworkUtils::setInterfaceConfigFail(NetworkParams& aOptions,
+                                          NetworkResultOptions& aResult)
+{
+  postMessage(aOptions, aResult);
+}
+
+void NetworkUtils::setInterfaceConfigSuccess(CommandChain* aChain,
+                                             CommandCallback aCallback,
+                                             NetworkResultOptions& aResult)
+{
+  postMessage(aChain->getParams(), aResult);
+  finalizeSuccess(aChain, aResult);
+}
+
+#undef ASSIGN_FIELD
+#undef ASSIGN_FIELD_VALUE
+
+NetworkUtils::NetworkUtils(MessageCallback aCallback)
+ : mMessageCallback(aCallback)
+{
+  mNetUtils = new NetUtils();
+
+  char value[Property::VALUE_MAX_LENGTH];
+  Property::Get("ro.build.version.sdk", value, nullptr);
+  SDK_VERSION = atoi(value);
+
+  Property::Get(IPV6_TETHERING, value, "0");
+  SUPPORT_IPV6_TETHERING = atoi(value);
+
+  gNetworkUtils = this;
+}
+
+NetworkUtils::~NetworkUtils()
+{
+}
+
+#define GET_CHAR(prop) NS_ConvertUTF16toUTF8(aOptions.prop).get()
+#define GET_FIELD(prop) aOptions.prop
+
+// Hoist this type definition to global to avoid template
+// instantiation error on gcc 4.4 used by ICS emulator.
+typedef CommandResult (NetworkUtils::*CommandHandler)(NetworkParams&);
+struct CommandHandlerEntry
+{
+  const char* mCommandName;
+  CommandHandler mCommandHandler;
+};
+
+void NetworkUtils::ExecuteCommand(NetworkParams aOptions)
+{
+  const static CommandHandlerEntry
+    COMMAND_HANDLER_TABLE[] = {
+
+    // For command 'testCommand', BUILD_ENTRY(testCommand) will generate
+    // {"testCommand", NetworkUtils::testCommand}
+    #define BUILD_ENTRY(c) {#c, &NetworkUtils::c}
+
+    BUILD_ENTRY(removeNetworkRoute),
+    BUILD_ENTRY(setDNS),
+    BUILD_ENTRY(setDefaultRoute),
+    BUILD_ENTRY(removeDefaultRoute),
+    BUILD_ENTRY(addHostRoute),
+    BUILD_ENTRY(removeHostRoute),
+    BUILD_ENTRY(addSecondaryRoute),
+    BUILD_ENTRY(removeSecondaryRoute),
+    BUILD_ENTRY(setNetworkInterfaceAlarm),
+    BUILD_ENTRY(enableNetworkInterfaceAlarm),
+    BUILD_ENTRY(disableNetworkInterfaceAlarm),
+    BUILD_ENTRY(setTetheringAlarm),
+    BUILD_ENTRY(removeTetheringAlarm),
+    BUILD_ENTRY(getTetheringStatus),
+    BUILD_ENTRY(setWifiOperationMode),
+    BUILD_ENTRY(setDhcpServer),
+    BUILD_ENTRY(setWifiTethering),
+    BUILD_ENTRY(setUSBTethering),
+    BUILD_ENTRY(enableUsbRndis),
+    BUILD_ENTRY(updateUpStream),
+    BUILD_ENTRY(configureInterface),
+    BUILD_ENTRY(dhcpRequest),
+    BUILD_ENTRY(stopDhcp),
+    BUILD_ENTRY(enableInterface),
+    BUILD_ENTRY(disableInterface),
+    BUILD_ENTRY(resetConnections),
+    BUILD_ENTRY(createNetwork),
+    BUILD_ENTRY(destroyNetwork),
+    BUILD_ENTRY(getNetId),
+    BUILD_ENTRY(getInterfaces),
+    BUILD_ENTRY(getInterfaceConfig),
+    BUILD_ENTRY(setInterfaceConfig),
+    BUILD_ENTRY(setMtu),
+
+    #undef BUILD_ENTRY
+  };
+
+  // Loop until we find the command name which matches aOptions.mCmd.
+  CommandHandler handler = nullptr;
+  for (size_t i = 0; i < mozilla::ArrayLength(COMMAND_HANDLER_TABLE); i++) {
+    if (aOptions.mCmd.EqualsASCII(COMMAND_HANDLER_TABLE[i].mCommandName)) {
+      handler = COMMAND_HANDLER_TABLE[i].mCommandHandler;
+      break;
+    }
+  }
+
+  if (!handler) {
+    // Command not found in COMMAND_HANDLER_TABLE.
+    WARN("unknown message: %s", NS_ConvertUTF16toUTF8(aOptions.mCmd).get());
+    return;
+  }
+
+  // The handler would return one of the following 3 values
+  // to be wrapped to CommandResult:
+  //
+  //   1) |int32_t| for mostly synchronous native function calls.
+  //   2) |NetworkResultOptions| to populate additional results. (e.g. dhcpRequest)
+  //   3) |CommandResult::Pending| to indicate the result is not
+  //      obtained yet.
+  //
+  // If the handler returns "Pending", the handler should take the
+  // responsibility for posting result to main thread.
+  CommandResult commandResult = (this->*handler)(aOptions);
+  if (!commandResult.isPending()) {
+    postMessage(aOptions, commandResult.mResult);
+  }
+}
+
+/**
+ * Handle received data from netd.
+ */
+void NetworkUtils::onNetdMessage(NetdCommand* aCommand)
+{
+  char* data = (char*)aCommand->mData;
+
+  // get code & reason.
+  char* result = strtok(data, NETD_MESSAGE_DELIMIT);
+
+  if (!result) {
+    nextNetdCommand();
+    return;
+  }
+  uint32_t code = atoi(result);
+
+  if (!isBroadcastMessage(code) && SDK_VERSION >= 16) {
+    strtok(nullptr, NETD_MESSAGE_DELIMIT);
+  }
+
+  char* reason = strtok(nullptr, "\0");
+
+  if (isBroadcastMessage(code)) {
+    NU_DBG("Receiving broadcast message from netd.");
+    NU_DBG("          ==> Code: %d  Reason: %s", code, reason);
+    sendBroadcastMessage(code, reason);
+
+    if (code == NETD_COMMAND_INTERFACE_CHANGE) {
+      if (gWifiTetheringParms) {
+        char linkdownReason[MAX_COMMAND_SIZE];
+        snprintf(linkdownReason, MAX_COMMAND_SIZE - 1,
+                 "Iface linkstate %s down",
+                 NS_ConvertUTF16toUTF8(gWifiTetheringParms->mIfname).get());
+
+        if (!strcmp(reason, linkdownReason)) {
+          NU_DBG("Wifi link down, restarting tethering.");
+          runChain(*gWifiTetheringParms, sWifiRetryChain, wifiTetheringFail);
+        }
+      }
+    }
+
+    nextNetdCommand();
+    return;
+  }
+
+   // Set pending to false before we handle next command.
+  NU_DBG("Receiving \"%s\" command response from netd.", gCurrentCommand.command);
+  NU_DBG("          ==> Code: %d  Reason: %s", code, reason);
+
+  gReason.AppendElement(nsCString(reason));
+
+  // 1xx response code regards as command is proceeding, we need to wait for
+  // final response code such as 2xx, 4xx and 5xx before sending next command.
+  if (isProceeding(code)) {
+    return;
+  }
+
+  if (isComplete(code)) {
+    gPending = false;
+  }
+
+  {
+    char buf[BUF_SIZE];
+    join(gReason, INTERFACE_DELIMIT, BUF_SIZE, buf);
+
+    NetworkResultOptions result;
+    result.mResultCode = code;
+    result.mResultReason = NS_ConvertUTF8toUTF16(buf);
+    (gCurrentCommand.callback)(gCurrentCommand.chain, isError(code), result);
+    gReason.Clear();
+  }
+
+  // Handling pending commands if any.
+  if (isComplete(code)) {
+    nextNetdCommand();
+  }
+}
+
+/**
+ * Start/Stop DHCP server.
+ */
+CommandResult NetworkUtils::setDhcpServer(NetworkParams& aOptions)
+{
+  if (aOptions.mEnabled) {
+    aOptions.mWifiStartIp = aOptions.mStartIp;
+    aOptions.mWifiEndIp = aOptions.mEndIp;
+    aOptions.mIp = aOptions.mServerIp;
+    aOptions.mPrefix = aOptions.mMaskLength;
+    aOptions.mLink = NS_ConvertUTF8toUTF16("up");
+
+    runChain(aOptions, sStartDhcpServerChain, setDhcpServerFail);
+  } else {
+    runChain(aOptions, sStopDhcpServerChain, setDhcpServerFail);
+  }
+  return CommandResult::Pending();
+}
+
+/**
+ * Set DNS servers for given network interface.
+ */
+CommandResult NetworkUtils::setDNS(NetworkParams& aOptions)
+{
+  uint32_t length = aOptions.mDnses.Length();
+
+  if (length > 0) {
+    for (uint32_t i = 0; i < length; i++) {
+      NS_ConvertUTF16toUTF8 autoDns(aOptions.mDnses[i]);
+
+      char dns_prop_key[Property::VALUE_MAX_LENGTH];
+      SprintfLiteral(dns_prop_key, "net.dns%d", i+1);
+      Property::Set(dns_prop_key, autoDns.get());
+    }
+  } else {
+    // Set dnses from system properties.
+    IFProperties interfaceProperties;
+    getIFProperties(GET_CHAR(mIfname), interfaceProperties);
+
+    Property::Set("net.dns1", interfaceProperties.dns1);
+    Property::Set("net.dns2", interfaceProperties.dns2);
+  }
+
+  // Bump the DNS change property.
+  char dnschange[Property::VALUE_MAX_LENGTH];
+  Property::Get("net.dnschange", dnschange, "0");
+
+  char num[Property::VALUE_MAX_LENGTH];
+  snprintf(num, Property::VALUE_MAX_LENGTH - 1, "%d", atoi(dnschange) + 1);
+  Property::Set("net.dnschange", num);
+
+  // DNS needs to be set through netd since JellyBean (4.3).
+  if (SDK_VERSION >= 20) {
+    // Lollipop.
+    static CommandFunc COMMAND_CHAIN[] = {
+      setInterfaceDns,
+      addDefaultRouteToNetwork,
+      defaultAsyncSuccessHandler
+    };
+    NetIdManager::NetIdInfo netIdInfo;
+    if (!mNetIdManager.lookup(aOptions.mIfname, &netIdInfo)) {
+      return -1;
+    }
+    aOptions.mNetId = netIdInfo.mNetId;
+    runChain(aOptions, COMMAND_CHAIN, setDnsFail);
+    return CommandResult::Pending();
+  }
+  if (SDK_VERSION >= 18) {
+    // JB, KK.
+    static CommandFunc COMMAND_CHAIN[] = {
+    #if ANDROID_VERSION == 18
+      // Since we don't use per-interface DNS lookup feature on JB,
+      // we need to set the default DNS interface whenever setting the
+      // DNS name server.
+      setDefaultInterface,
+    #endif
+      setInterfaceDns,
+      defaultAsyncSuccessHandler
+    };
+    runChain(aOptions, COMMAND_CHAIN, setDnsFail);
+    return CommandResult::Pending();
+  }
+
+  return SUCCESS;
+}
+
+CommandResult NetworkUtils::configureInterface(NetworkParams& aOptions)
+{
+  NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+  return mNetUtils->do_ifc_configure(
+    autoIfname.get(),
+    aOptions.mIpaddr,
+    aOptions.mMask,
+    aOptions.mGateway_long,
+    aOptions.mDns1_long,
+    aOptions.mDns2_long
+  );
+}
+
+CommandResult NetworkUtils::stopDhcp(NetworkParams& aOptions)
+{
+  return mNetUtils->do_dhcp_stop(GET_CHAR(mIfname));
+}
+
+CommandResult NetworkUtils::dhcpRequest(NetworkParams& aOptions) {
+    mozilla::dom::NetworkResultOptions result;
+
+    NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+    char ipaddr[Property::VALUE_MAX_LENGTH];
+    char gateway[Property::VALUE_MAX_LENGTH];
+    uint32_t prefixLength;
+    char dns1[Property::VALUE_MAX_LENGTH];
+    char dns2[Property::VALUE_MAX_LENGTH];
+    char server[Property::VALUE_MAX_LENGTH];
+    uint32_t lease;
+    char vendorinfo[Property::VALUE_MAX_LENGTH];
+    int32_t ret = mNetUtils->do_dhcp_do_request(autoIfname.get(),
+                                                ipaddr,
+                                                gateway,
+                                                &prefixLength,
+                                                dns1,
+                                                dns2,
+                                                server,
+                                                &lease,
+                                                vendorinfo);
+
+    RETURN_IF_FAILED(ret);
+
+    result.mIpaddr_str = NS_ConvertUTF8toUTF16(ipaddr);
+    result.mGateway_str = NS_ConvertUTF8toUTF16(gateway);
+    result.mDns1_str = NS_ConvertUTF8toUTF16(dns1);
+    result.mDns2_str = NS_ConvertUTF8toUTF16(dns2);
+    result.mServer_str = NS_ConvertUTF8toUTF16(server);
+    result.mVendor_str = NS_ConvertUTF8toUTF16(vendorinfo);
+    result.mLease = lease;
+    result.mPrefixLength = prefixLength;
+    result.mMask = makeMask(prefixLength);
+
+    uint32_t inet4; // only support IPv4 for now.
+
+#define INET_PTON(var, field)                                                 \
+  PR_BEGIN_MACRO                                                              \
+    inet_pton(AF_INET, var, &inet4);                                          \
+    result.field = inet4;                                                    \
+  PR_END_MACRO
+
+    INET_PTON(ipaddr, mIpaddr);
+    INET_PTON(gateway, mGateway);
+
+    if (dns1[0] != '\0') {
+      INET_PTON(dns1, mDns1);
+    }
+
+    if (dns2[0] != '\0') {
+      INET_PTON(dns2, mDns2);
+    }
+
+    INET_PTON(server, mServer);
+
+    char inet_str[64];
+    if (inet_ntop(AF_INET, &result.mMask, inet_str, sizeof(inet_str))) {
+      result.mMask_str = NS_ConvertUTF8toUTF16(inet_str);
+    }
+
+    return result;
+}
+
+CommandResult NetworkUtils::enableInterface(NetworkParams& aOptions) {
+  return mNetUtils->do_ifc_enable(
+    NS_ConvertUTF16toUTF8(aOptions.mIfname).get());
+}
+
+CommandResult NetworkUtils::disableInterface(NetworkParams& aOptions) {
+  return mNetUtils->do_ifc_disable(
+    NS_ConvertUTF16toUTF8(aOptions.mIfname).get());
+}
+
+CommandResult NetworkUtils::resetConnections(NetworkParams& aOptions) {
+  NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+  return mNetUtils->do_ifc_reset_connections(
+    NS_ConvertUTF16toUTF8(aOptions.mIfname).get(),
+    RESET_ALL_ADDRESSES);
+}
+
+/**
+ * Set default route and DNS servers for given network interface.
+ */
+CommandResult NetworkUtils::setDefaultRoute(NetworkParams& aOptions)
+{
+  if (SDK_VERSION < 20) {
+    return setDefaultRouteLegacy(aOptions);
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    addDefaultRouteToNetwork,
+    setDefaultNetwork,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (!mNetIdManager.lookup(GET_FIELD(mIfname), &netIdInfo)) {
+    ERROR("No such interface");
+    return -1;
+  }
+
+  aOptions.mNetId = netIdInfo.mNetId;
+  aOptions.mLoopIndex = 0;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+
+  return CommandResult::Pending();
+}
+
+/**
+ * Set default route and DNS servers for given network interface by obsoleted libnetutils.
+ */
+CommandResult NetworkUtils::setDefaultRouteLegacy(NetworkParams& aOptions)
+{
+  NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+
+  uint32_t length = aOptions.mGateways.Length();
+  if (length > 0) {
+    for (uint32_t i = 0; i < length; i++) {
+      NS_ConvertUTF16toUTF8 autoGateway(aOptions.mGateways[i]);
+
+      int type = getIpType(autoGateway.get());
+      if (type != AF_INET && type != AF_INET6) {
+        continue;
+      }
+
+      if (type == AF_INET6) {
+        RETURN_IF_FAILED(mNetUtils->do_ifc_add_route(autoIfname.get(), "::", 0, autoGateway.get()));
+      } else { /* type == AF_INET */
+        RETURN_IF_FAILED(mNetUtils->do_ifc_set_default_route(autoIfname.get(), inet_addr(autoGateway.get())));
+      }
+    }
+  } else {
+    // Set default froute from system properties.
+    char key[Property::KEY_MAX_LENGTH];
+    char gateway[Property::KEY_MAX_LENGTH];
+
+    snprintf(key, sizeof key - 1, "net.%s.gw", autoIfname.get());
+    Property::Get(key, gateway, "");
+
+    int type = getIpType(gateway);
+    if (type != AF_INET && type != AF_INET6) {
+      return EAFNOSUPPORT;
+    }
+
+    if (type == AF_INET6) {
+      RETURN_IF_FAILED(mNetUtils->do_ifc_add_route(autoIfname.get(), "::", 0, gateway));
+    } else { /* type == AF_INET */
+      RETURN_IF_FAILED(mNetUtils->do_ifc_set_default_route(autoIfname.get(), inet_addr(gateway)));
+    }
+  }
+
+  // Set the default DNS interface.
+  if (SDK_VERSION >= 18) {
+    // For JB, KK only.
+    static CommandFunc COMMAND_CHAIN[] = {
+      setDefaultInterface,
+      defaultAsyncSuccessHandler
+    };
+    runChain(aOptions, COMMAND_CHAIN, setDnsFail);
+    return CommandResult::Pending();
+  }
+
+  return SUCCESS;
+}
+
+/**
+ * Remove default route for given network interface.
+ */
+CommandResult NetworkUtils::removeDefaultRoute(NetworkParams& aOptions)
+{
+  NU_DBG("Calling NetworkUtils::removeDefaultRoute");
+
+  if (SDK_VERSION < 20) {
+    return removeDefaultRouteLegacy(aOptions);
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    removeDefaultRoute,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (!mNetIdManager.lookup(GET_FIELD(mIfname), &netIdInfo)) {
+    ERROR("No such interface: %s", GET_CHAR(mIfname));
+    return -1;
+  }
+
+  NU_DBG("Obtained netid %d for interface %s", netIdInfo.mNetId, GET_CHAR(mIfname));
+
+  aOptions.mNetId = netIdInfo.mNetId;
+  aOptions.mLoopIndex = 0;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+
+  return CommandResult::Pending();
+}
+
+/**
+ * Remove default route for given network interface by obsoleted libnetutils.
+ */
+CommandResult NetworkUtils::removeDefaultRouteLegacy(NetworkParams& aOptions)
+{
+  // Legacy libnetutils calls before Lollipop.
+  uint32_t length = aOptions.mGateways.Length();
+  for (uint32_t i = 0; i < length; i++) {
+    NS_ConvertUTF16toUTF8 autoGateway(aOptions.mGateways[i]);
+
+    int type = getIpType(autoGateway.get());
+    if (type != AF_INET && type != AF_INET6) {
+      return EAFNOSUPPORT;
+    }
+
+    WARN_IF_FAILED(mNetUtils->do_ifc_remove_route(GET_CHAR(mIfname),
+                                                  type == AF_INET ? "0.0.0.0" : "::",
+                                                  0, autoGateway.get()));
+  }
+
+  return SUCCESS;
+}
+
+/**
+ * Add host route for given network interface.
+ */
+CommandResult NetworkUtils::addHostRoute(NetworkParams& aOptions)
+{
+  if (SDK_VERSION < 20) {
+    return addHostRouteLegacy(aOptions);
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    addRouteToInterface,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (!mNetIdManager.lookup(GET_FIELD(mIfname), &netIdInfo)) {
+    ERROR("No such interface: %s", GET_CHAR(mIfname));
+    return -1;
+  }
+
+  NU_DBG("Obtained netid %d for interface %s", netIdInfo.mNetId, GET_CHAR(mIfname));
+
+  aOptions.mNetId = netIdInfo.mNetId;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+
+  return CommandResult::Pending();
+}
+
+/**
+ * Add host route for given network interface.
+ */
+CommandResult NetworkUtils::addHostRouteLegacy(NetworkParams& aOptions)
+{
+  if (aOptions.mGateway.IsEmpty()) {
+    ERROR("addHostRouteLegacy does not support empty gateway.");
+    return EINVAL;
+  }
+
+  NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+  NS_ConvertUTF16toUTF8 autoHostname(aOptions.mIp);
+  NS_ConvertUTF16toUTF8 autoGateway(aOptions.mGateway);
+  int type, prefix;
+
+  type = getIpType(autoHostname.get());
+  if (type != AF_INET && type != AF_INET6) {
+    return EAFNOSUPPORT;
+  }
+
+  if (type != getIpType(autoGateway.get())) {
+    return EINVAL;
+  }
+
+  prefix = type == AF_INET ? 32 : 128;
+  return mNetUtils->do_ifc_add_route(autoIfname.get(), autoHostname.get(),
+                                     prefix, autoGateway.get());
+}
+
+/**
+ * Remove host route for given network interface.
+ */
+CommandResult NetworkUtils::removeHostRoute(NetworkParams& aOptions)
+{
+  if (SDK_VERSION < 20) {
+    return removeHostRouteLegacy(aOptions);
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    removeRouteFromInterface,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (!mNetIdManager.lookup(GET_FIELD(mIfname), &netIdInfo)) {
+    ERROR("No such interface: %s", GET_CHAR(mIfname));
+    return -1;
+  }
+
+  NU_DBG("Obtained netid %d for interface %s", netIdInfo.mNetId, GET_CHAR(mIfname));
+
+  aOptions.mNetId = netIdInfo.mNetId;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+
+  return CommandResult::Pending();
+}
+
+/**
+ * Remove host route for given network interface.
+ */
+CommandResult NetworkUtils::removeHostRouteLegacy(NetworkParams& aOptions)
+{
+  NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+  NS_ConvertUTF16toUTF8 autoHostname(aOptions.mIp);
+  NS_ConvertUTF16toUTF8 autoGateway(aOptions.mGateway);
+  int type, prefix;
+
+  type = getIpType(autoHostname.get());
+  if (type != AF_INET && type != AF_INET6) {
+    return EAFNOSUPPORT;
+  }
+
+  if (type != getIpType(autoGateway.get())) {
+    return EINVAL;
+  }
+
+  prefix = type == AF_INET ? 32 : 128;
+  return mNetUtils->do_ifc_remove_route(autoIfname.get(), autoHostname.get(),
+                                        prefix, autoGateway.get());
+}
+
+CommandResult NetworkUtils::removeNetworkRoute(NetworkParams& aOptions)
+{
+  if (SDK_VERSION < 20) {
+    return removeNetworkRouteLegacy(aOptions);
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    clearAddrForInterface,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (!mNetIdManager.lookup(GET_FIELD(mIfname), &netIdInfo)) {
+    ERROR("interface %s is not present in any network", GET_CHAR(mIfname));
+    return -1;
+  }
+
+  NU_DBG("Obtained netid %d for interface %s", netIdInfo.mNetId, GET_CHAR(mIfname));
+
+  aOptions.mNetId = netIdInfo.mNetId;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+
+  return CommandResult::Pending();
+}
+
+nsCString NetworkUtils::getSubnetIp(const nsCString& aIp, int aPrefixLength)
+{
+  int type = getIpType(aIp.get());
+
+  if (AF_INET6 == type) {
+    struct in6_addr in6;
+    if (inet_pton(AF_INET6, aIp.get(), &in6) != 1) {
+      return nsCString();
+    }
+
+    uint32_t p, i, p1, mask;
+    p = aPrefixLength;
+    i = 0;
+    while (i < 4) {
+      p1 = p > 32 ? 32 : p;
+      p -= p1;
+      mask = p1 ? ~0x0 << (32 - p1) : 0;
+      in6.s6_addr32[i++] &= htonl(mask);
+    }
+
+    char subnetStr[INET6_ADDRSTRLEN];
+    if (!inet_ntop(AF_INET6, &in6, subnetStr, sizeof subnetStr)) {
+      return nsCString();
+    }
+
+    return nsCString(subnetStr);
+  }
+
+  if (AF_INET == type) {
+    uint32_t ip = inet_addr(aIp.get());
+    uint32_t netmask = makeMask(aPrefixLength);
+    uint32_t subnet = ip & netmask;
+    struct in_addr addr;
+    addr.s_addr = subnet;
+    return nsCString(inet_ntoa(addr));
+  }
+
+  return nsCString();
+}
+
+CommandResult NetworkUtils::removeNetworkRouteLegacy(NetworkParams& aOptions)
+{
+  NS_ConvertUTF16toUTF8 autoIfname(aOptions.mIfname);
+  NS_ConvertUTF16toUTF8 autoIp(aOptions.mIp);
+
+  int type = getIpType(autoIp.get());
+  if (type != AF_INET && type != AF_INET6) {
+    return EAFNOSUPPORT;
+  }
+
+  uint32_t prefixLength = GET_FIELD(mPrefixLength);
+
+  if (type == AF_INET6) {
+    // Calculate subnet.
+    struct in6_addr in6;
+    if (inet_pton(AF_INET6, autoIp.get(), &in6) != 1) {
+      return EINVAL;
+    }
+
+    uint32_t p, i, p1, mask;
+    p = prefixLength;
+    i = 0;
+    while (i < 4) {
+      p1 = p > 32 ? 32 : p;
+      p -= p1;
+      mask = p1 ? ~0x0 << (32 - p1) : 0;
+      in6.s6_addr32[i++] &= htonl(mask);
+    }
+
+    char subnetStr[INET6_ADDRSTRLEN];
+    if (!inet_ntop(AF_INET6, &in6, subnetStr, sizeof subnetStr)) {
+      return EINVAL;
+    }
+
+    // Remove default route.
+    WARN_IF_FAILED(mNetUtils->do_ifc_remove_route(autoIfname.get(), "::", 0, NULL));
+
+    // Remove subnet route.
+    RETURN_IF_FAILED(mNetUtils->do_ifc_remove_route(autoIfname.get(), subnetStr, prefixLength, NULL));
+    return SUCCESS;
+  }
+
+  /* type == AF_INET */
+  uint32_t ip = inet_addr(autoIp.get());
+  uint32_t netmask = makeMask(prefixLength);
+  uint32_t subnet = ip & netmask;
+  const char* gateway = "0.0.0.0";
+  struct in_addr addr;
+  addr.s_addr = subnet;
+  const char* dst = inet_ntoa(addr);
+
+  RETURN_IF_FAILED(mNetUtils->do_ifc_remove_default_route(autoIfname.get()));
+  RETURN_IF_FAILED(mNetUtils->do_ifc_remove_route(autoIfname.get(), dst, prefixLength, gateway));
+  return SUCCESS;
+}
+
+CommandResult NetworkUtils::addSecondaryRoute(NetworkParams& aOptions)
+{
+  static CommandFunc COMMAND_CHAIN[] = {
+    addRouteToSecondaryTable,
+    defaultAsyncSuccessHandler
+  };
+
+  if (SDK_VERSION >= 20) {
+    NetIdManager::NetIdInfo netIdInfo;
+    if (!mNetIdManager.lookup(aOptions.mIfname, &netIdInfo)) {
+      return -1;
+    }
+    aOptions.mNetId = netIdInfo.mNetId;
+  }
+
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::removeSecondaryRoute(NetworkParams& aOptions)
+{
+  static CommandFunc COMMAND_CHAIN[] = {
+    removeRouteFromSecondaryTable,
+    defaultAsyncSuccessHandler
+  };
+
+  if (SDK_VERSION >= 20) {
+    NetIdManager::NetIdInfo netIdInfo;
+    if (!mNetIdManager.lookup(aOptions.mIfname, &netIdInfo)) {
+      return -1;
+    }
+    aOptions.mNetId = netIdInfo.mNetId;
+  }
+
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::setNetworkInterfaceAlarm(NetworkParams& aOptions)
+{
+  NU_DBG("setNetworkInterfaceAlarms: %s", GET_CHAR(mIfname));
+  runChain(aOptions, sNetworkInterfaceSetAlarmChain, networkInterfaceAlarmFail);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::enableNetworkInterfaceAlarm(NetworkParams& aOptions)
+{
+  NU_DBG("enableNetworkInterfaceAlarm: %s", GET_CHAR(mIfname));
+  runChain(aOptions, sNetworkInterfaceEnableAlarmChain, networkInterfaceAlarmFail);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::disableNetworkInterfaceAlarm(NetworkParams& aOptions)
+{
+  NU_DBG("disableNetworkInterfaceAlarms: %s", GET_CHAR(mIfname));
+  runChain(aOptions, sNetworkInterfaceDisableAlarmChain, networkInterfaceAlarmFail);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::setTetheringAlarm(NetworkParams& aOptions)
+{
+  NU_DBG("setTetheringAlarm");
+  runChain(aOptions, sTetheringInterfaceSetAlarmChain, networkInterfaceAlarmFail);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::removeTetheringAlarm(NetworkParams& aOptions)
+{
+  NU_DBG("removeTetheringAlarm");
+  runChain(aOptions, sTetheringInterfaceRemoveAlarmChain, networkInterfaceAlarmFail);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::getTetheringStatus(NetworkParams& aOptions)
+{
+  NU_DBG("getTetheringStatus");
+  runChain(aOptions, sTetheringGetStatusChain, networkInterfaceAlarmFail);
+  return CommandResult::Pending();
+}
+
+/**
+ * handling main thread's reload Wifi firmware request
+ */
+CommandResult NetworkUtils::setWifiOperationMode(NetworkParams& aOptions)
+{
+  NU_DBG("setWifiOperationMode: %s %s", GET_CHAR(mIfname), GET_CHAR(mMode));
+  runChain(aOptions, sWifiOperationModeChain, wifiOperationModeFail);
+  return CommandResult::Pending();
+}
+
+/**
+ * handling main thread's enable/disable WiFi Tethering request
+ */
+CommandResult NetworkUtils::setWifiTethering(NetworkParams& aOptions)
+{
+  bool enable = aOptions.mEnable;
+  IFProperties interfaceProperties;
+  getIFProperties(GET_CHAR(mExternalIfname), interfaceProperties);
+
+  if (strcmp(interfaceProperties.dns1, "")) {
+    int type = getIpType(interfaceProperties.dns1);
+    if (type != AF_INET6) {
+      aOptions.mDns1 = NS_ConvertUTF8toUTF16(interfaceProperties.dns1);
+    }
+  }
+  if (strcmp(interfaceProperties.dns2, "")) {
+    int type = getIpType(interfaceProperties.dns2);
+    if (type != AF_INET6) {
+      aOptions.mDns2 = NS_ConvertUTF8toUTF16(interfaceProperties.dns2);
+    }
+  }
+  dumpParams(aOptions, "WIFI");
+
+  if (SDK_VERSION >= 20) {
+    NetIdManager::NetIdInfo netIdInfo;
+    if (!mNetIdManager.lookup(aOptions.mExternalIfname, &netIdInfo)) {
+      ERROR("No such interface: %s", GET_CHAR(mExternalIfname));
+      return -1;
+    }
+    aOptions.mNetId = netIdInfo.mNetId;
+  }
+
+  if (enable) {
+    NU_DBG("Starting Wifi Tethering on %s <-> %s",
+           GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname));
+    runChain(aOptions, sWifiEnableChain, wifiTetheringFail);
+  } else {
+    NU_DBG("Stopping Wifi Tethering on %s <-> %s",
+           GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname));
+    runChain(aOptions, sWifiDisableChain, wifiTetheringFail);
+  }
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::setUSBTethering(NetworkParams& aOptions)
+{
+  bool enable = aOptions.mEnable;
+  IFProperties interfaceProperties;
+  getIFProperties(GET_CHAR(mExternalIfname), interfaceProperties);
+
+  if (strcmp(interfaceProperties.dns1, "")) {
+    int type = getIpType(interfaceProperties.dns1);
+    if (type != AF_INET6) {
+      aOptions.mDns1 = NS_ConvertUTF8toUTF16(interfaceProperties.dns1);
+    }
+  }
+  if (strcmp(interfaceProperties.dns2, "")) {
+    int type = getIpType(interfaceProperties.dns2);
+    if (type != AF_INET6) {
+      aOptions.mDns2 = NS_ConvertUTF8toUTF16(interfaceProperties.dns2);
+    }
+  }
+  dumpParams(aOptions, "USB");
+
+  if (SDK_VERSION >= 20) {
+    NetIdManager::NetIdInfo netIdInfo;
+    if (!mNetIdManager.lookup(aOptions.mExternalIfname, &netIdInfo)) {
+      ERROR("No such interface: %s", GET_CHAR(mExternalIfname));
+      return -1;
+    }
+    aOptions.mNetId = netIdInfo.mNetId;
+  }
+
+  if (enable) {
+    NU_DBG("Starting USB Tethering on %s <-> %s",
+           GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname));
+    runChain(aOptions, sUSBEnableChain, usbTetheringFail);
+  } else {
+    NU_DBG("Stopping USB Tethering on %s <-> %s",
+           GET_CHAR(mInternalIfname), GET_CHAR(mExternalIfname));
+    runChain(aOptions, sUSBDisableChain, usbTetheringFail);
+  }
+  return CommandResult::Pending();
+}
+
+void NetworkUtils::escapeQuote(nsCString& aString)
+{
+  aString.ReplaceSubstring("\\", "\\\\");
+  aString.ReplaceSubstring("\"", "\\\"");
+}
+
+CommandResult NetworkUtils::checkUsbRndisState(NetworkParams& aOptions)
+{
+  static uint32_t retry = 0;
+
+  char currentState[Property::VALUE_MAX_LENGTH];
+  Property::Get(SYS_USB_STATE_PROPERTY, currentState, nullptr);
+
+  nsTArray<nsCString> stateFuncs;
+  split(currentState, USB_CONFIG_DELIMIT, stateFuncs);
+  bool rndisPresent = stateFuncs.Contains(nsCString(USB_FUNCTION_RNDIS));
+
+  if (aOptions.mEnable == rndisPresent) {
+    NetworkResultOptions result;
+    result.mEnable = aOptions.mEnable;
+    result.mResult = true;
+    retry = 0;
+    return result;
+  }
+  if (retry < USB_FUNCTION_RETRY_TIMES) {
+    retry++;
+    usleep(USB_FUNCTION_RETRY_INTERVAL * 1000);
+    return checkUsbRndisState(aOptions);
+  }
+
+  NetworkResultOptions result;
+  result.mResult = false;
+  retry = 0;
+  return result;
+}
+
+/**
+ * Modify usb function's property to turn on USB RNDIS function
+ */
+CommandResult NetworkUtils::enableUsbRndis(NetworkParams& aOptions)
+{
+  bool report = aOptions.mReport;
+
+  // For some reason, rndis doesn't play well with diag,modem,nmea.
+  // So when turning rndis on, we set sys.usb.config to either "rndis"
+  // or "rndis,adb". When turning rndis off, we go back to
+  // persist.sys.usb.config.
+  //
+  // On the otoro/unagi, persist.sys.usb.config should be one of:
+  //
+  //    diag,modem,nmea,mass_storage
+  //    diag,modem,nmea,mass_storage,adb
+  //
+  // When rndis is enabled, sys.usb.config should be one of:
+  //
+  //    rdnis
+  //    rndis,adb
+  //
+  // and when rndis is disabled, it should revert to persist.sys.usb.config
+
+  char currentConfig[Property::VALUE_MAX_LENGTH];
+  Property::Get(SYS_USB_CONFIG_PROPERTY, currentConfig, nullptr);
+
+  nsTArray<nsCString> configFuncs;
+  split(currentConfig, USB_CONFIG_DELIMIT, configFuncs);
+
+  char persistConfig[Property::VALUE_MAX_LENGTH];
+  Property::Get(PERSIST_SYS_USB_CONFIG_PROPERTY, persistConfig, nullptr);
+
+  nsTArray<nsCString> persistFuncs;
+  split(persistConfig, USB_CONFIG_DELIMIT, persistFuncs);
+
+  if (aOptions.mEnable) {
+    configFuncs.Clear();
+    configFuncs.AppendElement(nsCString(USB_FUNCTION_RNDIS));
+    if (persistFuncs.Contains(nsCString(USB_FUNCTION_ADB))) {
+      configFuncs.AppendElement(nsCString(USB_FUNCTION_ADB));
+    }
+  } else {
+    // We're turning rndis off, revert back to the persist setting.
+    // adb will already be correct there, so we don't need to do any
+    // further adjustments.
+    configFuncs = persistFuncs;
+  }
+
+  char newConfig[Property::VALUE_MAX_LENGTH] = "";
+  Property::Get(SYS_USB_CONFIG_PROPERTY, currentConfig, nullptr);
+  join(configFuncs, USB_CONFIG_DELIMIT, Property::VALUE_MAX_LENGTH, newConfig);
+  if (strcmp(currentConfig, newConfig)) {
+    Property::Set(SYS_USB_CONFIG_PROPERTY, newConfig);
+  }
+
+  // Trigger the timer to check usb state and report the result to NetworkManager.
+  if (report) {
+    usleep(USB_FUNCTION_RETRY_INTERVAL * 1000);
+    return checkUsbRndisState(aOptions);
+  }
+  return SUCCESS;
+}
+
+/**
+ * handling upstream interface change event.
+ */
+CommandResult NetworkUtils::updateUpStream(NetworkParams& aOptions)
+{
+  runChain(aOptions, sUpdateUpStreamChain, updateUpStreamFail);
+  return CommandResult::Pending();
+}
+
+/**
+ * handling upstream interface change event.
+ */
+CommandResult NetworkUtils::createNetwork(NetworkParams& aOptions)
+{
+  if (SDK_VERSION < 20) {
+    return SUCCESS;
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    createNetwork,
+    enableIpv6,
+    addInterfaceToNetwork,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  mNetIdManager.acquire(GET_FIELD(mIfname), &netIdInfo);
+  if (netIdInfo.mRefCnt > 1) {
+    // Already created. Just return.
+    NU_DBG("Interface %s (%d) has been created.", GET_CHAR(mIfname),
+                                                  netIdInfo.mNetId);
+    return SUCCESS;
+  }
+
+  NU_DBG("Request netd to create a network with netid %d", netIdInfo.mNetId);
+  // Newly created netid. Ask netd to create network.
+  aOptions.mNetId = netIdInfo.mNetId;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+
+  return CommandResult::Pending();
+}
+
+/**
+ * handling upstream interface change event.
+ */
+CommandResult NetworkUtils::destroyNetwork(NetworkParams& aOptions)
+{
+  if (SDK_VERSION < 20) {
+    return SUCCESS;
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    disableIpv6,
+    destroyNetwork,
+    defaultAsyncSuccessHandler,
+  };
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (!mNetIdManager.release(GET_FIELD(mIfname), &netIdInfo)) {
+    ERROR("No existing netid for %s", GET_CHAR(mIfname));
+    return -1;
+  }
+
+  if (netIdInfo.mRefCnt > 0) {
+    // Still be referenced. Just return.
+    NU_DBG("Someone is still using this interface.");
+    return SUCCESS;
+  }
+
+  NU_DBG("Interface %s (%d) is no longer used. Tell netd to destroy.",
+         GET_CHAR(mIfname), netIdInfo.mNetId);
+
+  aOptions.mNetId = netIdInfo.mNetId;
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+  return CommandResult::Pending();
+}
+
+/**
+ * Query the netId associated with the given network interface name.
+ */
+CommandResult NetworkUtils::getNetId(NetworkParams& aOptions)
+{
+  NetworkResultOptions result;
+
+  if (SDK_VERSION < 20) {
+    // For pre-Lollipop, use the interface name as the fallback.
+    result.mNetId = GET_FIELD(mIfname);
+    return result;
+  }
+
+  NetIdManager::NetIdInfo netIdInfo;
+  if (-1 == mNetIdManager.lookup(GET_FIELD(mIfname), &netIdInfo)) {
+    return ESRCH;
+  }
+  result.mNetId.AppendInt(netIdInfo.mNetId, 10);
+  return result;
+}
+
+/**
+ * Get existing network interfaces.
+ */
+CommandResult NetworkUtils::getInterfaces(NetworkParams& aOptions)
+{
+  runChain(aOptions, sGetInterfacesChain, getInterfacesFail);
+  return CommandResult::Pending();
+}
+
+/**
+ * Get network config of a specified interface.
+ */
+CommandResult NetworkUtils::getInterfaceConfig(NetworkParams& aOptions)
+{
+  runChain(aOptions, sGetInterfaceConfigChain, getInterfaceConfigFail);
+  return CommandResult::Pending();
+}
+
+/**
+ * Set network config for a specified interface.
+ */
+CommandResult NetworkUtils::setInterfaceConfig(NetworkParams& aOptions)
+{
+  runChain(aOptions, sSetInterfaceConfigChain, setInterfaceConfigFail);
+  return CommandResult::Pending();
+}
+
+CommandResult NetworkUtils::setMtu(NetworkParams& aOptions)
+{
+  // Setting/getting mtu is supported since Kitkat.
+  if (SDK_VERSION < 19) {
+    ERROR("setMtu is not supported in current SDK_VERSION.");
+    return -1;
+  }
+
+  static CommandFunc COMMAND_CHAIN[] = {
+    setMtu,
+    defaultAsyncSuccessHandler,
+  };
+
+  runChain(aOptions, COMMAND_CHAIN, defaultAsyncFailureHandler);
+  return CommandResult::Pending();
+}
+
+void NetworkUtils::sendBroadcastMessage(uint32_t code, char* reason)
+{
+  NetworkResultOptions result;
+  switch(code) {
+    case NETD_COMMAND_INTERFACE_CHANGE:
+      result.mTopic = NS_ConvertUTF8toUTF16("netd-interface-change");
+      break;
+    case NETD_COMMAND_BANDWIDTH_CONTROLLER:
+      result.mTopic = NS_ConvertUTF8toUTF16("netd-bandwidth-control");
+      break;
+    default:
+      return;
+  }
+
+  result.mBroadcast = true;
+  result.mReason = NS_ConvertUTF8toUTF16(reason);
+  postMessage(result);
+}
+
+inline uint32_t NetworkUtils::netdResponseType(uint32_t code)
+{
+  return (code / 100) * 100;
+}
+
+inline bool NetworkUtils::isBroadcastMessage(uint32_t code)
+{
+  uint32_t type = netdResponseType(code);
+  return type == NETD_COMMAND_UNSOLICITED;
+}
+
+inline bool NetworkUtils::isError(uint32_t code)
+{
+  uint32_t type = netdResponseType(code);
+  return type != NETD_COMMAND_PROCEEDING && type != NETD_COMMAND_OKAY;
+}
+
+inline bool NetworkUtils::isComplete(uint32_t code)
+{
+  uint32_t type = netdResponseType(code);
+  return type != NETD_COMMAND_PROCEEDING;
+}
+
+inline bool NetworkUtils::isProceeding(uint32_t code)
+{
+  uint32_t type = netdResponseType(code);
+  return type == NETD_COMMAND_PROCEEDING;
+}
+
+void NetworkUtils::dumpParams(NetworkParams& aOptions, const char* aType)
+{
+#ifdef _DEBUG
+  NU_DBG("Dump params:");
+  NU_DBG("     ifname: %s", GET_CHAR(mIfname));
+  NU_DBG("     ip: %s", GET_CHAR(mIp));
+  NU_DBG("     link: %s", GET_CHAR(mLink));
+  NU_DBG("     prefix: %s", GET_CHAR(mPrefix));
+  NU_DBG("     wifiStartIp: %s", GET_CHAR(mWifiStartIp));
+  NU_DBG("     wifiEndIp: %s", GET_CHAR(mWifiEndIp));
+  NU_DBG("     usbStartIp: %s", GET_CHAR(mUsbStartIp));
+  NU_DBG("     usbEndIp: %s", GET_CHAR(mUsbEndIp));
+  NU_DBG("     dnsserver1: %s", GET_CHAR(mDns1));
+  NU_DBG("     dnsserver2: %s", GET_CHAR(mDns2));
+  NU_DBG("     internalIfname: %s", GET_CHAR(mInternalIfname));
+  NU_DBG("     externalIfname: %s", GET_CHAR(mExternalIfname));
+  if (!strcmp(aType, "WIFI")) {
+    NU_DBG("     wifictrlinterfacename: %s", GET_CHAR(mWifictrlinterfacename));
+    NU_DBG("     ssid: %s", GET_CHAR(mSsid));
+    NU_DBG("     security: %s", GET_CHAR(mSecurity));
+    NU_DBG("     key: %s", GET_CHAR(mKey));
+  }
+#endif
+}
+
+#undef GET_CHAR
+#undef GET_FIELD