Mac OS X-specific implementation of Networking Private API.

components/wifi/wifi_service_mac.mm

+// Copyright 2013 The Chromium Authors. All rights reserved.

[tbarzic, 2014/01/08 23:06:23]

the copyright header is out of date :P

[mef, 2014/01/09 22:41:46]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/wifi/wifi_service.h"
+
+#import <netinet/in.h>
+#import <CoreWLAN/CoreWLAN.h>
+#import <SystemConfiguration/SystemConfiguration.h>
+
+#include "base/bind.h"
+#include "base/mac/scoped_cftyperef.h"
+#include "base/mac/scoped_nsautorelease_pool.h"
+#include "base/mac/scoped_nsobject.h"
+#include "base/message_loop/message_loop.h"
+#include "base/strings/sys_string_conversions.h"
+#include "components/onc/onc_constants.h"
+
+namespace {
+// Declare notification names from the 10.7 SDK.
+const char* kCWSSIDDidChangeNotification_chrome =
+    "com.apple.coreWLAN.notification.ssid";
+}  // namespace
+
+#if !defined(MAC_OS_X_VERSION_10_7) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
+
+// Local definitions of API added in Mac OS X 10.7
+
+@interface CWInterface (LionAPI)
+- (BOOL)associateToNetwork:(CWNetwork*)network
+                  password:(NSString*)password
+                     error:(NSError**)error;
+- (NSSet*)scanForNetworksWithName:(NSString*)networkName
+                            error:(NSError**)error;
+@end
+
+enum CWChannelBand {
+  kCWChannelBandUnknown = 0,
+  kCWChannelBand2GHz = 1,
+  kCWChannelBand5GHz = 2,
+};
+
+@interface CWChannel : NSObject
+@property(readonly) CWChannelBand channelBand;
+@end
+
+@interface CWNetwork (LionAPI)
+@property(readonly) CWChannel* wlanChannel;
+@end
+
+#endif  // 10.7
+
+namespace wifi {
+
+const char kErrorAssociateToNetwork[] = "Error.AssociateToNetwork";
+const char kErrorGetProperties[] = "Error.GetProperties";
+const char kErrorNotConnected[] = "Error.NotConnected";
+const char kErrorNotFound[] = "Error.NotFound";
+const char kErrorNotImplemented[] = "Error.NotImplemented";
+const char kErrorScanForNetworksWithName[] = "Error.ScanForNetworksWithName";
+
+// Implementation of WiFiService for Mac OS X.
+class WiFiServiceMac : public WiFiService {
+ public:
+  WiFiServiceMac();
+  virtual ~WiFiServiceMac();
+
+  // WiFiService interface implementation.
+  virtual void Initialize(
+      scoped_refptr<base::SequencedTaskRunner> task_runner) OVERRIDE;
+
+  virtual void UnInitialize() OVERRIDE;
+
+  virtual void GetProperties(const std::string& network_guid,
+                             base::DictionaryValue* properties,
+                             std::string* error) OVERRIDE;
+
+  virtual void GetManagedProperties(const std::string& network_guid,
+                                    base::DictionaryValue* managed_properties,
+                                    std::string* error) OVERRIDE;
+
+  virtual void GetState(const std::string& network_guid,
+                        base::DictionaryValue* properties,
+                        std::string* error) OVERRIDE;
+
+  virtual void SetProperties(const std::string& network_guid,
+                             scoped_ptr<base::DictionaryValue> properties,
+                             std::string* error) OVERRIDE;
+
+  virtual void CreateNetwork(bool shared,
+                             scoped_ptr<base::DictionaryValue> properties,
+                             std::string* network_guid,
+                             std::string* error) OVERRIDE;
+
+  virtual void GetVisibleNetworks(const std::string& network_type,
+                                  base::ListValue* network_list) OVERRIDE;
+
+  virtual void RequestNetworkScan() OVERRIDE;
+
+  virtual void StartConnect(const std::string& network_guid,
+                            std::string* error) OVERRIDE;
+
+  virtual void StartDisconnect(const std::string& network_guid,
+                               std::string* error) OVERRIDE;
+
+  virtual void SetEventObservers(
+      scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
+      const NetworkGuidListCallback& networks_changed_observer,
+      const NetworkGuidListCallback& network_list_changed_observer) OVERRIDE;
+
+ private:
+  // Check |ns_error| and if is not |nil|, then store |error_name|
+  // into |error|.
+  bool CheckError(NSError* ns_error,
+                  const char* error_name,
+                  std::string* error) const;
+
+  // Get |ssid| from unique |network_guid|.
+  NSString* SSIDFromGUID(const std::string& network_guid) const {
+    return base::SysUTF8ToNSString(network_guid);
+  }
+
+  // Get unique |network_guid| string based on |ssid|.
+  std::string GUIDFromSSID(NSString* ssid) const {
+    return base::SysNSStringToUTF8(ssid);
+  }
+
+  // Populate |properties| from |network|.
+  void NetworkPropertiesFromCWNetwork(const CWNetwork* network,
+                                      NetworkProperties* properties) const;
+
+  // Convert |CWSecurityMode| into onc::wifi::k{WPA|WEP}* security constant.
+  std::string SecurityFromCWSecurityMode(CWSecurityMode security) const;
+
+  // Wait up to |kMaxAttempts| with |kAttemptDelayMs| delay for connection
+  // to network with |network_guid|. Notify that |NetworkChanged| upon success.
+  void WaitForNetworkConnect(const std::string& network_guid, int attempt);
+
+  // Get the list of visible wireless networks. If |network_guid| is not empty,
+  // then only return that network.
+  NSError* GetVisibleNetworkList(const std::string& network_guid,
+                                 NetworkList* network_list);
+
+  // Handle notification from |wlan_observer_|;

[tbarzic, 2014/01/08 23:06:23]

end comment with . instead of ;

Here and throughout: Method comments should be descriptive rather than
imperative.

[mef, 2014/01/09 22:41:46]

Done.

+  void OnWlanObserverNotification();
+
+  // Notify |network_list_changed_observer_| that list of visible networks has
+  // changed to |networks|.
+  void NotifyNetworkListChanged(const NetworkList& networks);
+
+  // Notify |networks_changed_observer_| that network |network_guid| status has
+  // changed.
+  void NotifyNetworkChanged(const std::string& network_guid);
+
+  // CoreWLAN.Framework bundle.
+  base::scoped_nsobject<NSBundle> bundle_;
+  // Default interface.
+  base::scoped_nsobject<CWInterface> interface_;
+  // WLAN Notifications observer.
+  base::scoped_nsobject<NSObject> wlan_observer_;
+
+  // Observer to get notified when network(s) have changed (e.g. connect).
+  NetworkGuidListCallback networks_changed_observer_;
+  // Observer to get notified when network list has changed (scan complete).
+  NetworkGuidListCallback network_list_changed_observer_;
+  // MessageLoopProxy to post events on UI thread.
+  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
+  // Task runner for worker tasks.
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+  // Cache of network list collected by GetVisibleNetworks.
+  NetworkList networks_;
+  // Temporary storage of network properties indexed by |network_guid|.
+  base::DictionaryValue network_properties_;
+  // If |false|, then |networks_changed_observer_| is not notified.
+  bool enable_notify_network_changed_;
+  // Number of attempts to check that network has connected successfully.
+  static const int kConnectionCheckMaxAttempts = 200;
+  // Delay between attempts to check that network has connected successfully.
+  static const int kConnectionCheckAttemptDelayMs = 100;
+};
+
+WiFiServiceMac::WiFiServiceMac() : enable_notify_network_changed_(true) {
+}
+
+WiFiServiceMac::~WiFiServiceMac() {
+}
+
+void WiFiServiceMac::Initialize(
+  scoped_refptr<base::SequencedTaskRunner> task_runner) {
+  // As the WLAN api binding runs on its own thread, we need to provide our own
+  // auto release pool. It's simplest to do this as an automatic variable in
+  // each method that needs it, to ensure the scoping is correct and does not
+  // interfere with any other code using autorelease pools on the thread.
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+
+  task_runner_.swap(task_runner);
+
+  bundle_.reset([[NSBundle alloc]
+      initWithPath:@"/System/Library/Frameworks/CoreWLAN.framework"]);
+  if (!bundle_) {
+    DVLOG(1) << "Failed to load the CoreWLAN framework bundle";
+    return;
+  }
+
+  Class cw_interface_class = [bundle_ classNamed:@"CWInterface"];
+  interface_.reset([[cw_interface_class interface] retain]);
+  if (!bundle_) {
+    DVLOG(1) << "Failed to initialize default interface";
+    return;
+  }
+
+}
+
+void WiFiServiceMac::UnInitialize() {
+  [[NSNotificationCenter defaultCenter] removeObserver:wlan_observer_];
+}
+
+void WiFiServiceMac::GetProperties(const std::string& network_guid,
+                                    base::DictionaryValue* properties,
+                                    std::string* error) {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+
+  if (networks_.empty()) {

[tbarzic, 2014/01/08 23:06:23]

I don't think this block is needed (at least if RequestNetworkScan is changed to
update networks_). If a network is not in networks_, the extension using the API
should not know about it.

[mef, 2014/01/09 22:41:46]

Done.

+    DVLOG(1) << "GetProperties";
+    NSError* ns_error = GetVisibleNetworkList(std::string(), &networks_);
+    if (CheckError(ns_error, kErrorGetProperties, error))
+      return;
+  }
+
+  for (WiFiService::NetworkList::iterator it = networks_.begin();
+       it != networks_.end();
+       ++it) {
+    if (it->guid == network_guid) {

[tbarzic, 2014/01/08 23:06:23]

the network's properties should probably be rescaned here, to make sure the
extension gets up to date information.

[mef, 2014/01/09 22:41:46]

Done.

+      bool is_connected = network_guid == GUIDFromSSID([interface_ ssid]);
+      it->connection_state =
+          is_connected ? onc::connection_state::kConnected :
+                         onc::connection_state::kNotConnected;
+      scoped_ptr<base::DictionaryValue> network(it->ToValue(false));
+      properties->Swap(network.get());
+      DVLOG(1) << *properties;
+      return;
+    }
+  }
+
+  *error = kErrorNotFound;
+}
+
+void WiFiServiceMac::GetManagedProperties(
+    const std::string& network_guid,
+    base::DictionaryValue* managed_properties,
+    std::string* error) {
+  *error = kErrorNotImplemented;
+}
+
+void WiFiServiceMac::GetState(const std::string& network_guid,
+                               base::DictionaryValue* properties,
+                               std::string* error) {
+  *error = kErrorNotImplemented;
+}
+
+void WiFiServiceMac::SetProperties(
+    const std::string& network_guid,
+    scoped_ptr<base::DictionaryValue> properties,
+    std::string* error) {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  network_properties_.SetWithoutPathExpansion(network_guid,
+                                              properties.release());
+}
+
+void WiFiServiceMac::CreateNetwork(
+    bool shared,
+    scoped_ptr<base::DictionaryValue> properties,
+    std::string* network_guid,
+    std::string* error) {
+  *error = kErrorNotImplemented;
+}
+
+void WiFiServiceMac::GetVisibleNetworks(const std::string& network_type,
+                                         base::ListValue* network_list) {
+  if (!network_type.empty() &&
+      network_type != onc::network_type::kAllTypes &&
+      network_type != onc::network_type::kWiFi) {
+    return;
+  }
+
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+
+  GetVisibleNetworkList(std::string(), &networks_);
+
+  // Sort networks, so connected/connecting is up front.
+  networks_.sort(NetworkProperties::OrderByType);
+
+  for (WiFiService::NetworkList::const_iterator it = networks_.begin();
+       it != networks_.end();
+       ++it) {
+    scoped_ptr<base::DictionaryValue> network(it->ToValue(true));
+    network_list->Append(network.release());
+  }
+}
+
+void WiFiServiceMac::RequestNetworkScan() {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  NetworkList networks;
+
+  NSError* ns_error = GetVisibleNetworkList(std::string(), &networks);
+  if (ns_error == nil && !networks.empty()) {
+    NotifyNetworkListChanged(networks);
+  }
+}
+
+void WiFiServiceMac::StartConnect(const std::string& network_guid,
+                                   std::string* error) {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  NSError* ns_error = nil;
+
+  DVLOG(1) << "*** StartConnect: " << network_guid;
+  // Remember previously connected network.
+  std::string connected_network_guid = GUIDFromSSID([interface_ ssid]);
+  // Check, whether desired network is already connected.
+  if (network_guid == connected_network_guid) {
+    NotifyNetworkChanged(connected_network_guid);
+    return;
+  }
+
+  NSSet* networks = [interface_
+      scanForNetworksWithName:SSIDFromGUID(network_guid)
+                        error:&ns_error];
+
+  if (CheckError(ns_error, kErrorScanForNetworksWithName, error))
+    return;
+
+  CWNetwork* network = [networks anyObject];
+  if (network == nil) {
+    *error = kErrorNotFound;
+    return;
+  }
+
+  // Check whether WiFi Password is set in |network_properties_|
+  base::DictionaryValue* properties;
+  base::DictionaryValue* wifi;
+  std::string passphrase;
+  NSString* ns_password = nil;
+  if (network_properties_.GetDictionaryWithoutPathExpansion(network_guid,
+                                                            &properties) &&
+      properties->GetDictionary(onc::network_type::kWiFi, &wifi) &&
+      wifi->GetString(onc::wifi::kPassphrase, &passphrase)) {
+    ns_password = base::SysUTF8ToNSString(passphrase);
+  }
+
+  // Disable automatic network change notifications as they get fired
+  // when network is just connected, but not yet accessible (doesn't
+  // have valid IP address).
+  enable_notify_network_changed_ = false;
+  // Number of attempts to associate to network.
+  static const int kMaxAssociationAttempts = 3;
+  // Try to associate to network several times if timeout or PMK error occurs.
+  for (int i = 0; i < kMaxAssociationAttempts; ++i) {
+    // Nil out the PMK to prevent stale data from causing invalid PMK error
+    // (CoreWLANTypes -3924).
+    [interface_ setPairwiseMasterKey:nil error:&ns_error];
+    if ([interface_ associateToNetwork:network
+                              password:ns_password
+                                 error:&ns_error]) {
+      // Notify that previously connected network has changed.
+      NotifyNetworkChanged(connected_network_guid);
+
+      // Start waiting for network connection state change. WaiForNetworkConnect
+      // is async and  it'll reset enable_notify_network_changed_.
+      if (!networks_changed_observer_.is_null()) {
+        WaitForNetworkConnect(network_guid, 0);
+        return;
+      }
+    } else {
+      NSInteger error_code = [ns_error code];
+      if (error_code != kCWTimeoutErr && error_code != kCWInvalidPMKErr) {
+        break;
+      }
+    }
+  }
+  enable_notify_network_changed_ = true;
+  CheckError(ns_error, kErrorAssociateToNetwork, error);
+}
+
+void WiFiServiceMac::StartDisconnect(const std::string& network_guid,
+                                      std::string* error) {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  DVLOG(1) << "*** StartDisconnect: " << network_guid;
+
+  if (network_guid == GUIDFromSSID([interface_ ssid])) {
+    [interface_ disassociate];
+  } else {
+    *error = kErrorNotConnected;
+  }
+}
+
+void WiFiServiceMac::SetEventObservers(
+    scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
+    const NetworkGuidListCallback& networks_changed_observer,
+    const NetworkGuidListCallback& network_list_changed_observer) {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  message_loop_proxy_.swap(message_loop_proxy);
+  networks_changed_observer_ = networks_changed_observer;
+  network_list_changed_observer_ = network_list_changed_observer;
+
+  // Subscribe to OS notifications.
+  wlan_observer_.reset([[NSNotificationCenter defaultCenter]
+      addObserverForName:base::SysUTF8ToNSString(
+                             kCWSSIDDidChangeNotification_chrome)
+                  object:nil
+                   queue:nil
+              usingBlock:^(NSNotification* notification) {
+          task_runner_->PostTask(
+              FROM_HERE,
+              base::Bind(&WiFiServiceMac::OnWlanObserverNotification,
+                         base::Unretained(this)));
+        }]);
+}
+
+void WiFiServiceMac::WaitForNetworkConnect(const std::string& network_guid,
+                                            int attempt) {
+  // If network didn't get connected in |kMaxAttempts|, then restore automatic
+  // network change notifications and stop waiting.
+  if (attempt > kConnectionCheckMaxAttempts) {
+    DLOG(ERROR) << kConnectionCheckMaxAttempts
+                << " attempts exceeded waiting for connect to "
+                << network_guid;
+    // Restore previously suppressed notifications.
+    enable_notify_network_changed_ = true;
+    return;
+  }
+
+  // Check whether WiFi network is reachable.
+  struct sockaddr_in local_wifi_address;
+  bzero(&local_wifi_address, sizeof(local_wifi_address));
+  local_wifi_address.sin_len = sizeof(local_wifi_address);
+  local_wifi_address.sin_family = AF_INET;
+  local_wifi_address.sin_addr.s_addr = htonl(IN_LINKLOCALNETNUM);
+
+  base::ScopedCFTypeRef<SCNetworkReachabilityRef> reachability(
+      SCNetworkReachabilityCreateWithAddress(
+          kCFAllocatorDefault,
+          reinterpret_cast<const struct sockaddr*>(&local_wifi_address)));
+  SCNetworkReachabilityFlags flags = 0u;
+  if (SCNetworkReachabilityGetFlags(reachability, &flags) &&
+      (flags & kSCNetworkReachabilityFlagsReachable) &&
+      (flags & kSCNetworkReachabilityFlagsIsDirect)) {
+    DVLOG(1) << "WiFi Connected, Reachable: " << network_guid;
+    // Restore previously suppressed notifications.
+    enable_notify_network_changed_ = true;
+    NotifyNetworkChanged(network_guid);
+  } else {
+    DVLOG(1) << "Attempt:"  << attempt << ", reachability:" << flags;
+    // Continue waiting for network connection state change.
+    task_runner_->PostDelayedTask(
+        FROM_HERE,
+        base::Bind(&WiFiServiceMac::WaitForNetworkConnect,
+                   base::Unretained(this),
+                   network_guid,
+                   ++attempt),
+        base::TimeDelta::FromMilliseconds(kConnectionCheckAttemptDelayMs));
+  }
+}
+
+
+NSError* WiFiServiceMac::GetVisibleNetworkList(const std::string& network_guid,

[tbarzic, 2014/01/08 23:06:23]

Instead of returning network_list here, why don't you rename the method to
|UpdateNetworks| and update networks_ (and trigger network list changed event).

If |network_guid| is set, you could only update the properties for said network
(and add the network to the list if needed).

[mef, 2014/01/09 22:41:46]

Done.

+                                                NetworkList* network_list) {
+
+  NSError* ns_error = nil;
+  NSString* network_name = nil;
+
+  DVLOG(1) << "<<< GetVisibleNetworkList: " << network_guid;
+
+  if (!network_guid.empty())
+    network_name = SSIDFromGUID(network_guid);
+
+  NSSet* networks = [interface_ scanForNetworksWithName:network_name
+                                                  error:&ns_error];
+  if (ns_error != nil)
+    return ns_error;
+
+  std::map<std::string, NetworkProperties*> network_properties_map;
+
+  CWNetwork* network;
+  // There is one |network| per BSS in |networks|, so go through the set and
+  // combine them, paying attention to supported frequencies.
+  for (network in networks) {

[tbarzic, 2014/01/08 23:06:23]

should network_list be cleared before the loop?

[mef, 2014/01/09 22:41:46]

Done.

+    NetworkProperties network_properties;
+    NetworkPropertiesFromCWNetwork(network, &network_properties);
+
+    if (network_properties_map.find(network_properties.guid) ==
+        network_properties_map.end()) {
+      network_list->push_back(network_properties);
+      network_properties_map[network_properties.guid] = &network_list->back();
+    } else {
+      NetworkProperties* existing = network_properties_map.at(
+          network_properties.guid);
+      existing->frequency_set.insert(*network_properties.frequency_set.begin());
+    }
+  }
+  DVLOG(1) << ">>> GetVisibleNetworkList: " << network_guid;
+
+  return nil;
+}
+
+bool WiFiServiceMac::CheckError(NSError* ns_error,
+                                 const char* error_name,
+                                 std::string* error) const {
+  if (ns_error != nil) {
+    DLOG(ERROR) << "*** Error:" << error_name << ":" << [ns_error code];
+    *error = error_name;
+    return true;
+  }
+  return false;
+}
+
+void WiFiServiceMac::NetworkPropertiesFromCWNetwork(
+    const CWNetwork* network,
+    NetworkProperties* properties) const {
+
+  if ([[network ssid] compare:[interface_ ssid]] == NSOrderedSame)
+    properties->connection_state = onc::connection_state::kConnected;
+  else
+    properties->connection_state = onc::connection_state::kNotConnected;
+
+  properties->ssid = base::SysNSStringToUTF8([network ssid]);
+  properties->name = properties->ssid;
+  properties->guid = GUIDFromSSID([network ssid]);
+  properties->type = onc::network_type::kWiFi;
+
+  properties->bssid = base::SysNSStringToUTF8([network bssid]);
+  if ([[network wlanChannel] channelBand] == kCWChannelBand2GHz)
+    properties->frequency = kFrequency2400;
+  else
+    properties->frequency = kFrequency5000;
+  properties->frequency_set.insert(properties->frequency);
+  properties->security = SecurityFromCWSecurityMode(
+      static_cast<CWSecurityMode>([[network securityMode] intValue]));
+
+  properties->signal_strength = [[network rssi] intValue];
+}
+
+std::string WiFiServiceMac::SecurityFromCWSecurityMode(
+    CWSecurityMode security) const {
+  switch (security) {
+    case kCWSecurityModeWPA_Enterprise:
+    case kCWSecurityModeWPA2_Enterprise:
+      return onc::wifi::kWPA_EAP;
+    case kCWSecurityModeWPA_PSK:
+    case kCWSecurityModeWPA2_PSK:
+      return onc::wifi::kWPA_PSK;
+    case kCWSecurityModeWEP:
+      return onc::wifi::kWEP_PSK;
+    case kCWSecurityModeOpen:
+      return onc::wifi::kNone;
+    // TODO(mef): Figure out correct mapping.
+    case kCWSecurityModeWPS:
+    case kCWSecurityModeDynamicWEP:
+      return onc::wifi::kWPA_EAP;
+  }
+  return onc::wifi::kWPA_EAP;
+}
+
+void WiFiServiceMac::OnWlanObserverNotification() {
+  std::string connected_network_guid = GUIDFromSSID([interface_ ssid]);
+  DVLOG(1) << " *** Got Notification: " << connected_network_guid;
+  if (connected_network_guid.empty()) {
+    // Find previously connected network and notify that it is disconnected.
+    for (WiFiService::NetworkList::iterator it = networks_.begin();
+         it != networks_.end();
+         ++it) {
+      if (it->connection_state == onc::connection_state::kConnected) {
+        it->connection_state = onc::connection_state::kNotConnected;
+        NotifyNetworkChanged(it->guid);
+      }
+    }
+  } else {
+    NotifyNetworkChanged(connected_network_guid);

[tbarzic, 2014/01/08 23:06:23]

You should make sure that networks_ contains the connected network, and if it
does not, update the network list before triggering this event. It would be ok
to scan for the connected network only (and add it to network list).

[mef, 2014/01/09 22:41:46]

Done.

+  }
+}
+
+void WiFiServiceMac::NotifyNetworkListChanged(const NetworkList& networks) {
+  if (network_list_changed_observer_.is_null())
+    return;
+
+  NetworkGuidList current_networks;
+  for (NetworkList::const_iterator it = networks.begin();
+       it != networks.end();
+       ++it) {
+    current_networks.push_back(it->guid);
+  }
+
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(network_list_changed_observer_, current_networks));
+}
+
+void WiFiServiceMac::NotifyNetworkChanged(const std::string& network_guid) {
+  if (!enable_notify_network_changed_ || networks_changed_observer_.is_null())
+    return;
+
+  DVLOG(1) << "NotifyNetworkChanged: " << network_guid;
+  NetworkGuidList changed_networks(1, network_guid);
+  message_loop_proxy_->PostTask(
+      FROM_HERE,
+      base::Bind(networks_changed_observer_, changed_networks));
+}
+
+// static
+WiFiService* WiFiService::Create() { return new WiFiServiceMac(); }
+
+}  // namespace wifi