components/wifi/wifi_service_mac.mm

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/wifi/wifi_service.h"
   6
   7 #import <netinet/in.h>
   8 #import <CoreWLAN/CoreWLAN.h>
   9 #import <SystemConfiguration/SystemConfiguration.h>
  10
  11 #include "base/bind.h"
  12 #include "base/mac/foundation_util.h"
  13 #include "base/mac/scoped_cftyperef.h"
  14 #include "base/mac/scoped_nsobject.h"
  15 #include "base/message_loop/message_loop.h"
  16 #include "base/strings/sys_string_conversions.h"
  17 #include "components/onc/onc_constants.h"
  18
  19 #if !defined(MAC_OS_X_VERSION_10_7) || \
  20     MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
  21
  22 // Local definitions of API added in Mac OS X 10.7
  23
  24 @interface CWInterface (LionAPI)
  25 - (BOOL)associateToNetwork:(CWNetwork*)network
  26                   password:(NSString*)password
  27                      error:(NSError**)error;
  28 - (NSSet*)scanForNetworksWithName:(NSString*)networkName
  29                             error:(NSError**)error;
  30 @end
  31
  32 enum CWChannelBand {
  33   kCWChannelBandUnknown = 0,
  34   kCWChannelBand2GHz = 1,
  35   kCWChannelBand5GHz = 2,
  36 };
  37
  38 @interface CWChannel : NSObject
  39 @property(readonly) CWChannelBand channelBand;
  40 @end
  41
  42 @interface CWNetwork (LionAPI)
  43 @property(readonly) CWChannel* wlanChannel;
  44 @end
  45
  46 #endif  // 10.7
  47
  48 namespace wifi {
  49
  50 const char kErrorAssociateToNetwork[] = "Error.AssociateToNetwork";
  51 const char kErrorInvalidData[] = "Error.InvalidData";
  52 const char kErrorNotConnected[] = "Error.NotConnected";
  53 const char kErrorNotFound[] = "Error.NotFound";
  54 const char kErrorNotImplemented[] = "Error.NotImplemented";
  55 const char kErrorScanForNetworksWithName[] = "Error.ScanForNetworksWithName";
  56
  57 // Implementation of WiFiService for Mac OS X.
  58 class WiFiServiceMac : public WiFiService {
  59  public:
  60   WiFiServiceMac();
  61   virtual ~WiFiServiceMac();
  62
  63   // WiFiService interface implementation.
  64   virtual void Initialize(
  65       scoped_refptr<base::SequencedTaskRunner> task_runner) OVERRIDE;
  66
  67   virtual void UnInitialize() OVERRIDE;
  68
  69   virtual void GetProperties(const std::string& network_guid,
  70                              base::DictionaryValue* properties,
  71                              std::string* error) OVERRIDE;
  72
  73   virtual void GetManagedProperties(const std::string& network_guid,
  74                                     base::DictionaryValue* managed_properties,
  75                                     std::string* error) OVERRIDE;
  76
  77   virtual void GetState(const std::string& network_guid,
  78                         base::DictionaryValue* properties,
  79                         std::string* error) OVERRIDE;
  80
  81   virtual void SetProperties(const std::string& network_guid,
  82                              scoped_ptr<base::DictionaryValue> properties,
  83                              std::string* error) OVERRIDE;
  84
  85   virtual void CreateNetwork(bool shared,
  86                              scoped_ptr<base::DictionaryValue> properties,
  87                              std::string* network_guid,
  88                              std::string* error) OVERRIDE;
  89
  90   virtual void GetVisibleNetworks(const std::string& network_type,
  91                                   base::ListValue* network_list) OVERRIDE;
  92
  93   virtual void RequestNetworkScan() OVERRIDE;
  94
  95   virtual void StartConnect(const std::string& network_guid,
  96                             std::string* error) OVERRIDE;
  97
  98   virtual void StartDisconnect(const std::string& network_guid,
  99                                std::string* error) OVERRIDE;
 100
 101   virtual void GetKeyFromSystem(const std::string& network_guid,
 102                                 std::string* key_data,
 103                                 std::string* error) OVERRIDE;
 104
 105   virtual void SetEventObservers(
 106       scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
 107       const NetworkGuidListCallback& networks_changed_observer,
 108       const NetworkGuidListCallback& network_list_changed_observer) OVERRIDE;
 109
 110   virtual void RequestConnectedNetworkUpdate() OVERRIDE;
 111
 112  private:
 113   // Checks |ns_error| and if is not |nil|, then stores |error_name|
 114   // into |error|.
 115   bool CheckError(NSError* ns_error,
 116                   const char* error_name,
 117                   std::string* error) const;
 118
 119   // Gets |ssid| from unique |network_guid|.
 120   NSString* SSIDFromGUID(const std::string& network_guid) const {
 121     return base::SysUTF8ToNSString(network_guid);
 122   }
 123
 124   // Gets unique |network_guid| string based on |ssid|.
 125   std::string GUIDFromSSID(NSString* ssid) const {
 126     return base::SysNSStringToUTF8(ssid);
 127   }
 128
 129   // Populates |properties| from |network|.
 130   void NetworkPropertiesFromCWNetwork(const CWNetwork* network,
 131                                       NetworkProperties* properties) const;
 132
 133   // Converts |CWSecurityMode| into onc::wifi::k{WPA|WEP}* security constant.
 134   std::string SecurityFromCWSecurityMode(CWSecurityMode security) const;
 135
 136   // Converts |CWChannelBand| into WiFiService::Frequency constant.
 137   Frequency FrequencyFromCWChannelBand(CWChannelBand band) const;
 138
 139   // Gets current |onc::connection_state| for given |network_guid|.
 140   std::string GetNetworkConnectionState(const std::string& network_guid) const;
 141
 142   // Updates |networks_| with the list of visible wireless networks.
 143   void UpdateNetworks();
 144
 145   // Find network by |network_guid| and return iterator to its entry in
 146   // |networks_|.
 147   NetworkList::iterator FindNetwork(const std::string& network_guid);
 148
 149   // Handles notification from |wlan_observer_|.
 150   void OnWlanObserverNotification();
 151
 152   // Notifies |network_list_changed_observer_| that list of visible networks has
 153   // changed to |networks|.
 154   void NotifyNetworkListChanged(const NetworkList& networks);
 155
 156   // Notifies |networks_changed_observer_| that network |network_guid|
 157   // connection state has changed.
 158   void NotifyNetworkChanged(const std::string& network_guid);
 159
 160   // Default interface.
 161   base::scoped_nsobject<CWInterface> interface_;
 162   // WLAN Notifications observer. |this| doesn't own this reference.
 163   id wlan_observer_;
 164
 165   // Observer to get notified when network(s) have changed (e.g. connect).
 166   NetworkGuidListCallback networks_changed_observer_;
 167   // Observer to get notified when network list has changed.
 168   NetworkGuidListCallback network_list_changed_observer_;
 169   // MessageLoopProxy to which events should be posted.
 170   scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
 171   // Task runner for worker tasks.
 172   scoped_refptr<base::SequencedTaskRunner> task_runner_;
 173   // Cached list of visible networks. Updated by |UpdateNetworks|.
 174   NetworkList networks_;
 175   // Guid of last known connected network.
 176   std::string connected_network_guid_;
 177   // Temporary storage of network properties indexed by |network_guid|.
 178   base::DictionaryValue network_properties_;
 179
 180   DISALLOW_COPY_AND_ASSIGN(WiFiServiceMac);
 181 };
 182
 183 WiFiServiceMac::WiFiServiceMac() : wlan_observer_(nil) {
 184 }
 185
 186 WiFiServiceMac::~WiFiServiceMac() {
 187 }
 188
 189 void WiFiServiceMac::Initialize(
 190   scoped_refptr<base::SequencedTaskRunner> task_runner) {
 191   task_runner_.swap(task_runner);
 192   interface_.reset([[CWInterface interface] retain]);
 193   if (!interface_) {
 194     DVLOG(1) << "Failed to initialize default interface.";
 195     return;
 196   }
 197
 198   if (![interface_
 199           respondsToSelector:@selector(associateToNetwork:password:error:)]) {
 200     DVLOG(1) << "CWInterface does not support associateToNetwork.";
 201     interface_.reset();
 202     return;
 203   }
 204 }
 205
 206 void WiFiServiceMac::UnInitialize() {
 207   if (wlan_observer_)
 208     [[NSNotificationCenter defaultCenter] removeObserver:wlan_observer_];
 209   interface_.reset();
 210 }
 211
 212 void WiFiServiceMac::GetProperties(const std::string& network_guid,
 213                                    base::DictionaryValue* properties,
 214                                    std::string* error) {
 215   NetworkList::iterator it = FindNetwork(network_guid);
 216   if (it == networks_.end()) {
 217     DVLOG(1) << "Network not found:" << network_guid;
 218     *error = kErrorNotFound;
 219     return;
 220   }
 221
 222   it->connection_state = GetNetworkConnectionState(network_guid);
 223   scoped_ptr<base::DictionaryValue> network(it->ToValue(false));
 224   properties->Swap(network.get());
 225   DVLOG(1) << *properties;
 226 }
 227
 228 void WiFiServiceMac::GetManagedProperties(
 229     const std::string& network_guid,
 230     base::DictionaryValue* managed_properties,
 231     std::string* error) {
 232   *error = kErrorNotImplemented;
 233 }
 234
 235 void WiFiServiceMac::GetState(const std::string& network_guid,
 236                               base::DictionaryValue* properties,
 237                               std::string* error) {
 238   *error = kErrorNotImplemented;
 239 }
 240
 241 void WiFiServiceMac::SetProperties(
 242     const std::string& network_guid,
 243     scoped_ptr<base::DictionaryValue> properties,
 244     std::string* error) {
 245   network_properties_.SetWithoutPathExpansion(network_guid,
 246                                               properties.release());
 247 }
 248
 249 void WiFiServiceMac::CreateNetwork(
 250     bool shared,
 251     scoped_ptr<base::DictionaryValue> properties,
 252     std::string* network_guid,
 253     std::string* error) {
 254   WiFiService::NetworkProperties network_properties;
 255   if (!network_properties.UpdateFromValue(*properties)) {
 256     *error = kErrorInvalidData;
 257     return;
 258   }
 259
 260   std::string guid = network_properties.ssid;
 261   if (FindNetwork(guid) != networks_.end()) {
 262     *error = kErrorInvalidData;
 263     return;
 264   }
 265   network_properties_.SetWithoutPathExpansion(guid,
 266                                               properties.release());
 267   *network_guid = guid;
 268 }
 269
 270 void WiFiServiceMac::GetVisibleNetworks(const std::string& network_type,
 271                                         base::ListValue* network_list) {
 272   if (!network_type.empty() &&
 273       network_type != onc::network_type::kAllTypes &&
 274       network_type != onc::network_type::kWiFi) {
 275     return;
 276   }
 277
 278   if (networks_.empty())
 279     UpdateNetworks();
 280
 281   for (WiFiService::NetworkList::const_iterator it = networks_.begin();
 282        it != networks_.end();
 283        ++it) {
 284     scoped_ptr<base::DictionaryValue> network(it->ToValue(true));
 285     network_list->Append(network.release());
 286   }
 287 }
 288
 289 void WiFiServiceMac::RequestNetworkScan() {
 290   DVLOG(1) << "*** RequestNetworkScan";
 291   UpdateNetworks();
 292 }
 293
 294 void WiFiServiceMac::StartConnect(const std::string& network_guid,
 295                                   std::string* error) {
 296   NSError* ns_error = nil;
 297
 298   DVLOG(1) << "*** StartConnect: " << network_guid;
 299   // Remember previously connected network.
 300   std::string connected_network_guid = GUIDFromSSID([interface_ ssid]);
 301   // Check whether desired network is already connected.
 302   if (network_guid == connected_network_guid)
 303     return;
 304
 305   NSSet* networks = [interface_
 306       scanForNetworksWithName:SSIDFromGUID(network_guid)
 307                         error:&ns_error];
 308
 309   if (CheckError(ns_error, kErrorScanForNetworksWithName, error))
 310     return;
 311
 312   CWNetwork* network = [networks anyObject];
 313   if (network == nil) {
 314     // System can't find the network, remove it from the |networks_| and notify
 315     // observers.
 316     NetworkList::iterator it = FindNetwork(connected_network_guid);
 317     if (it != networks_.end()) {
 318       networks_.erase(it);
 319       // Notify observers that list has changed.
 320       NotifyNetworkListChanged(networks_);
 321     }
 322
 323     *error = kErrorNotFound;
 324     return;
 325   }
 326
 327   // Check whether WiFi Password is set in |network_properties_|.
 328   base::DictionaryValue* properties;
 329   base::DictionaryValue* wifi;
 330   std::string passphrase;
 331   NSString* ns_password = nil;
 332   if (network_properties_.GetDictionaryWithoutPathExpansion(network_guid,
 333                                                             &properties) &&
 334       properties->GetDictionary(onc::network_type::kWiFi, &wifi) &&
 335       wifi->GetString(onc::wifi::kPassphrase, &passphrase)) {
 336     ns_password = base::SysUTF8ToNSString(passphrase);
 337   }
 338
 339   // Number of attempts to associate to network.
 340   static const int kMaxAssociationAttempts = 3;
 341   // Try to associate to network several times if timeout or PMK error occurs.
 342   for (int i = 0; i < kMaxAssociationAttempts; ++i) {
 343     // Nil out the PMK to prevent stale data from causing invalid PMK error
 344     // (CoreWLANTypes -3924).
 345     [interface_ setPairwiseMasterKey:nil error:&ns_error];
 346     if (![interface_ associateToNetwork:network
 347                               password:ns_password
 348                                  error:&ns_error]) {
 349       NSInteger error_code = [ns_error code];
 350       if (error_code != kCWTimeoutErr && error_code != kCWInvalidPMKErr) {
 351         break;
 352       }
 353     }
 354   }
 355   CheckError(ns_error, kErrorAssociateToNetwork, error);
 356 }
 357
 358 void WiFiServiceMac::StartDisconnect(const std::string& network_guid,
 359                                      std::string* error) {
 360   DVLOG(1) << "*** StartDisconnect: " << network_guid;
 361
 362   if (network_guid == GUIDFromSSID([interface_ ssid])) {
 363     // Power-cycle the interface to disconnect from current network and connect
 364     // to default network.
 365     NSError* ns_error = nil;
 366     [interface_ setPower:NO error:&ns_error];
 367     CheckError(ns_error, kErrorAssociateToNetwork, error);
 368     [interface_ setPower:YES error:&ns_error];
 369     CheckError(ns_error, kErrorAssociateToNetwork, error);
 370   } else {
 371     *error = kErrorNotConnected;
 372   }
 373 }
 374
 375 void WiFiServiceMac::GetKeyFromSystem(const std::string& network_guid,
 376                                       std::string* key_data,
 377                                       std::string* error) {
 378   static const char kAirPortServiceName[] = "AirPort";
 379
 380   UInt32 password_length = 0;
 381   void *password_data = NULL;
 382   OSStatus status = SecKeychainFindGenericPassword(NULL,
 383                                                    strlen(kAirPortServiceName),
 384                                                    kAirPortServiceName,
 385                                                    network_guid.length(),
 386                                                    network_guid.c_str(),
 387                                                    &password_length,
 388                                                    &password_data,
 389                                                    NULL);
 390   if (status != errSecSuccess) {
 391     *error = kErrorNotFound;
 392     return;
 393   }
 394
 395   if (password_data) {
 396     *key_data = std::string(reinterpret_cast<char*>(password_data),
 397                             password_length);
 398     SecKeychainItemFreeContent(NULL, password_data);
 399   }
 400 }
 401
 402 void WiFiServiceMac::SetEventObservers(
 403     scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
 404     const NetworkGuidListCallback& networks_changed_observer,
 405     const NetworkGuidListCallback& network_list_changed_observer) {
 406   message_loop_proxy_.swap(message_loop_proxy);
 407   networks_changed_observer_ = networks_changed_observer;
 408   network_list_changed_observer_ = network_list_changed_observer;
 409
 410   // Remove previous OS notifications observer.
 411   if (wlan_observer_) {
 412     [[NSNotificationCenter defaultCenter] removeObserver:wlan_observer_];
 413     wlan_observer_ = nil;
 414   }
 415
 416   // Subscribe to OS notifications.
 417   if (!networks_changed_observer_.is_null()) {
 418     void (^ns_observer) (NSNotification* notification) =
 419         ^(NSNotification* notification) {
 420             DVLOG(1) << "Received CWSSIDDidChangeNotification";
 421             task_runner_->PostTask(
 422                 FROM_HERE,
 423                 base::Bind(&WiFiServiceMac::OnWlanObserverNotification,
 424                            base::Unretained(this)));
 425     };
 426
 427     wlan_observer_ = [[NSNotificationCenter defaultCenter]
 428         addObserverForName:kCWSSIDDidChangeNotification
 429                     object:nil
 430                      queue:nil
 431                 usingBlock:ns_observer];
 432   }
 433 }
 434
 435 void WiFiServiceMac::RequestConnectedNetworkUpdate() {
 436   OnWlanObserverNotification();
 437 }
 438
 439 std::string WiFiServiceMac::GetNetworkConnectionState(
 440     const std::string& network_guid) const {
 441   if (network_guid != GUIDFromSSID([interface_ ssid]))
 442     return onc::connection_state::kNotConnected;
 443
 444   // Check whether WiFi network is reachable.
 445   struct sockaddr_in local_wifi_address;
 446   bzero(&local_wifi_address, sizeof(local_wifi_address));
 447   local_wifi_address.sin_len = sizeof(local_wifi_address);
 448   local_wifi_address.sin_family = AF_INET;
 449   local_wifi_address.sin_addr.s_addr = htonl(IN_LINKLOCALNETNUM);
 450   base::ScopedCFTypeRef<SCNetworkReachabilityRef> reachability(
 451       SCNetworkReachabilityCreateWithAddress(
 452           kCFAllocatorDefault,
 453           reinterpret_cast<const struct sockaddr*>(&local_wifi_address)));
 454   SCNetworkReachabilityFlags flags = 0u;
 455   if (SCNetworkReachabilityGetFlags(reachability, &flags) &&
 456       (flags & kSCNetworkReachabilityFlagsReachable) &&
 457       (flags & kSCNetworkReachabilityFlagsIsDirect)) {
 458     // Network is reachable, report is as |kConnected|.
 459     return onc::connection_state::kConnected;
 460   }
 461   // Network is not reachable yet, so it must be |kConnecting|.
 462   return onc::connection_state::kConnecting;
 463 }
 464
 465 void WiFiServiceMac::UpdateNetworks() {
 466   NSError* ns_error = nil;
 467   NSSet* cw_networks = [interface_ scanForNetworksWithName:nil
 468                                                      error:&ns_error];
 469   if (ns_error != nil)
 470     return;
 471
 472   std::string connected_bssid = base::SysNSStringToUTF8([interface_ bssid]);
 473   std::map<std::string, NetworkProperties*> network_properties_map;
 474   networks_.clear();
 475
 476   // There is one |cw_network| per BSS in |cw_networks|, so go through the set
 477   // and combine them, paying attention to supported frequencies.
 478   for (CWNetwork* cw_network in cw_networks) {
 479     std::string network_guid = GUIDFromSSID([cw_network ssid]);
 480     bool update_all_properties = false;
 481
 482     if (network_properties_map.find(network_guid) ==
 483             network_properties_map.end()) {
 484       networks_.push_back(NetworkProperties());
 485       network_properties_map[network_guid] = &networks_.back();
 486       update_all_properties = true;
 487     }
 488     // If current network is connected, use its properties for this network.
 489     if (base::SysNSStringToUTF8([cw_network bssid]) == connected_bssid)
 490       update_all_properties = true;
 491
 492     NetworkProperties* properties = network_properties_map.at(network_guid);
 493     if (update_all_properties) {
 494       NetworkPropertiesFromCWNetwork(cw_network, properties);
 495     } else {
 496       properties->frequency_set.insert(FrequencyFromCWChannelBand(
 497           [[cw_network wlanChannel] channelBand]));
 498     }
 499   }
 500   // Sort networks, so connected/connecting is up front.
 501   networks_.sort(NetworkProperties::OrderByType);
 502   // Notify observers that list has changed.
 503   NotifyNetworkListChanged(networks_);
 504 }
 505
 506 bool WiFiServiceMac::CheckError(NSError* ns_error,
 507                                 const char* error_name,
 508                                 std::string* error) const {
 509   if (ns_error != nil) {
 510     DLOG(ERROR) << "*** Error:" << error_name << ":" << [ns_error code];
 511     *error = error_name;
 512     return true;
 513   }
 514   return false;
 515 }
 516
 517 void WiFiServiceMac::NetworkPropertiesFromCWNetwork(
 518     const CWNetwork* network,
 519     NetworkProperties* properties) const {
 520   std::string network_guid = GUIDFromSSID([network ssid]);
 521
 522   properties->connection_state = GetNetworkConnectionState(network_guid);
 523   properties->ssid = base::SysNSStringToUTF8([network ssid]);
 524   properties->name = properties->ssid;
 525   properties->guid = network_guid;
 526   properties->type = onc::network_type::kWiFi;
 527
 528   properties->bssid = base::SysNSStringToUTF8([network bssid]);
 529   properties->frequency = FrequencyFromCWChannelBand(
 530       static_cast<CWChannelBand>([[network wlanChannel] channelBand]));
 531   properties->frequency_set.insert(properties->frequency);
 532   properties->security = SecurityFromCWSecurityMode(
 533       static_cast<CWSecurityMode>([[network securityMode] intValue]));
 534
 535   properties->signal_strength = [[network rssi] intValue];
 536 }
 537
 538 std::string WiFiServiceMac::SecurityFromCWSecurityMode(
 539     CWSecurityMode security) const {
 540   switch (security) {
 541     case kCWSecurityModeWPA_Enterprise:
 542     case kCWSecurityModeWPA2_Enterprise:
 543       return onc::wifi::kWPA_EAP;
 544     case kCWSecurityModeWPA_PSK:
 545     case kCWSecurityModeWPA2_PSK:
 546       return onc::wifi::kWPA_PSK;
 547     case kCWSecurityModeWEP:
 548       return onc::wifi::kWEP_PSK;
 549     case kCWSecurityModeOpen:
 550       return onc::wifi::kNone;
 551     // TODO(mef): Figure out correct mapping.
 552     case kCWSecurityModeWPS:
 553     case kCWSecurityModeDynamicWEP:
 554       return onc::wifi::kWPA_EAP;
 555   }
 556   return onc::wifi::kWPA_EAP;
 557 }
 558
 559
 560 WiFiService::Frequency WiFiServiceMac::FrequencyFromCWChannelBand(
 561     CWChannelBand band) const {
 562   return band == kCWChannelBand2GHz ? kFrequency2400 : kFrequency5000;
 563 }
 564
 565 WiFiService::NetworkList::iterator WiFiServiceMac::FindNetwork(
 566     const std::string& network_guid) {
 567   for (NetworkList::iterator it = networks_.begin();
 568        it != networks_.end();
 569        ++it) {
 570     if (it->guid == network_guid)
 571       return it;
 572   }
 573   return networks_.end();
 574 }
 575
 576 void WiFiServiceMac::OnWlanObserverNotification() {
 577   std::string connected_network_guid = GUIDFromSSID([interface_ ssid]);
 578   DVLOG(1) << " *** Got Notification: " << connected_network_guid;
 579   // Connected network has changed, mark previous one disconnected.
 580   if (connected_network_guid != connected_network_guid_) {
 581     // Update connection_state of newly connected network.
 582     NetworkList::iterator it = FindNetwork(connected_network_guid_);
 583     if (it != networks_.end()) {
 584       it->connection_state = onc::connection_state::kNotConnected;
 585       NotifyNetworkChanged(connected_network_guid_);
 586     }
 587     connected_network_guid_ = connected_network_guid;
 588   }
 589
 590   if (!connected_network_guid.empty()) {
 591     // Update connection_state of newly connected network.
 592     NetworkList::iterator it = FindNetwork(connected_network_guid);
 593     if (it != networks_.end()) {
 594       it->connection_state = GetNetworkConnectionState(connected_network_guid);
 595     } else {
 596       // Can't find |connected_network_guid| in |networks_|, try to update it.
 597       UpdateNetworks();
 598     }
 599     // Notify that network is connecting.
 600     NotifyNetworkChanged(connected_network_guid);
 601     // Further network change notification will be sent by detector.
 602   }
 603 }
 604
 605 void WiFiServiceMac::NotifyNetworkListChanged(const NetworkList& networks) {
 606   if (network_list_changed_observer_.is_null())
 607     return;
 608
 609   NetworkGuidList current_networks;
 610   for (NetworkList::const_iterator it = networks.begin();
 611        it != networks.end();
 612        ++it) {
 613     current_networks.push_back(it->guid);
 614   }
 615
 616   message_loop_proxy_->PostTask(
 617       FROM_HERE,
 618       base::Bind(network_list_changed_observer_, current_networks));
 619 }
 620
 621 void WiFiServiceMac::NotifyNetworkChanged(const std::string& network_guid) {
 622   if (networks_changed_observer_.is_null())
 623     return;
 624
 625   DVLOG(1) << "NotifyNetworkChanged: " << network_guid;
 626   NetworkGuidList changed_networks(1, network_guid);
 627   message_loop_proxy_->PostTask(
 628       FROM_HERE,
 629       base::Bind(networks_changed_observer_, changed_networks));
 630 }
 631
 632 // static
 633 WiFiService* WiFiService::Create() { return new WiFiServiceMac(); }
 634
 635 }  // namespace wifi