Mac OS X-specific implementation of Networking Private API.

components/wifi/wifi_service_mac.mm

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// 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_nsobject.h"
+#include "base/message_loop/message_loop.h"
+#include "base/strings/sys_string_conversions.h"
+#include "components/onc/onc_constants.h"
+
+#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 kErrorInvalidData[] = "Error.InvalidData";
+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;
+
+  virtual void OnNetworkChangeNotification() OVERRIDE;
+
+ private:
+  // Checks |ns_error| and if is not |nil|, then stores |error_name|
+  // into |error|.
+  bool CheckError(NSError* ns_error,
+                  const char* error_name,
+                  std::string* error) const;
+
+  // Gets |ssid| from unique |network_guid|.
+  NSString* SSIDFromGUID(const std::string& network_guid) const {
+    return base::SysUTF8ToNSString(network_guid);
+  }
+
+  // Gets unique |network_guid| string based on |ssid|.
+  std::string GUIDFromSSID(NSString* ssid) const {
+    return base::SysNSStringToUTF8(ssid);
+  }
+
+  // Populates |properties| from |network|.
+  void NetworkPropertiesFromCWNetwork(const CWNetwork* network,
+                                      NetworkProperties* properties) const;
+
+  // Converts |CWSecurityMode| into onc::wifi::k{WPA|WEP}* security constant.
+  std::string SecurityFromCWSecurityMode(CWSecurityMode security) const;
+
+  // Gets current |onc::connection_state| for given |network_guid|.
+  std::string GetNetworkConnectionState(const std::string& network_guid) const;
+
+  // Updates |networks_| with the list of visible wireless networks.
+  void UpdateNetworks();
+
+  // Find network by |network_guid| and return iterator to its entry in
+  // |networks_|.
+  NetworkList::iterator FindNetwork(const std::string& network_guid);
+
+  // Handles notification from |wlan_observer_|.
+  void OnWlanObserverNotification();
+
+  // Notifies |network_list_changed_observer_| that list of visible networks has
+  // changed to |networks|.
+  void NotifyNetworkListChanged(const NetworkList& networks);
+
+  // Notifies |networks_changed_observer_| that network |network_guid|
+  // connection state has changed.
+  void NotifyNetworkChanged(const std::string& network_guid);
+
+  // Default interface.
+  base::scoped_nsobject<CWInterface> interface_;
+  // WLAN Notifications observer. |this| doesn't own this reference.
+  id 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).

[tbarzic, 2014/01/28 02:05:03]

I'd drop "scan complete" part

[mef, 2014/01/28 14:39:36]

Done.

+  NetworkGuidListCallback network_list_changed_observer_;
+  // MessageLoopProxy to post events on UI thread.

[tbarzic, 2014/01/28 02:05:03]

MessageLoopProxy to which events should be posted.

(wifi_service should not care which message loop that really is)

[mef, 2014/01/28 14:39:36]

Done.

+  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.

[tbarzic, 2014/01/28 02:05:03]

Cached list of visible networks. Updated by |UpdateNetworks|.

[mef, 2014/01/28 14:39:36]

Done.

+  NetworkList networks_;
+  // Guid of last known connected network.
+  std::string connected_network_guid_;
+  // Temporary storage of network properties indexed by |network_guid|.
+  base::DictionaryValue network_properties_;
+  // Use WeakPtrs for callbacks from |network_change_detector_|.
+  base::WeakPtrFactory<WiFiServiceMac> weak_factory_;

[tbarzic, 2014/01/28 02:05:03]

not needed anymore

[mef, 2014/01/28 14:39:36]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(WiFiServiceMac);
+
+};
+
+WiFiServiceMac::WiFiServiceMac() : wlan_observer_(nil), weak_factory_(this) {
+}
+
+WiFiServiceMac::~WiFiServiceMac() {
+}
+
+void WiFiServiceMac::Initialize(
+  scoped_refptr<base::SequencedTaskRunner> task_runner) {
+  task_runner_.swap(task_runner);
+  interface_.reset([[CWInterface interface] retain]);
+  if (!interface_) {
+    DVLOG(1) << "Failed to initialize default interface.";
+    return;
+  }
+
+  if (![interface_
+          respondsToSelector:@selector(associateToNetwork:password:error:)]) {
+    DVLOG(1) << "CWInterface does not support associateToNetwork.";
+    interface_.reset();
+    return;
+  }
+}
+
+void WiFiServiceMac::UnInitialize() {
+  if (wlan_observer_)
+    [[NSNotificationCenter defaultCenter] removeObserver:wlan_observer_];
+  interface_.reset();
+}
+
+void WiFiServiceMac::GetProperties(const std::string& network_guid,
+                                   base::DictionaryValue* properties,
+                                   std::string* error) {
+  NetworkList::iterator it = FindNetwork(network_guid);
+  if (it == networks_.end()) {
+    DVLOG(1) << "Network not found:" << network_guid;
+    *error = kErrorNotFound;
+    return;
+  }
+
+  it->connection_state = GetNetworkConnectionState(network_guid);
+  scoped_ptr<base::DictionaryValue> network(it->ToValue(false));
+  properties->Swap(network.get());
+  DVLOG(1) << *properties;
+}
+
+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) {
+  network_properties_.SetWithoutPathExpansion(network_guid,
+                                              properties.release());
+}
+
+void WiFiServiceMac::CreateNetwork(
+    bool shared,
+    scoped_ptr<base::DictionaryValue> properties,
+    std::string* network_guid,
+    std::string* error) {
+  WiFiService::NetworkProperties network_properties;
+  if (!network_properties.UpdateFromValue(*properties)) {
+    *error = kErrorInvalidData;
+    return;
+  }
+
+  std::string guid = network_properties.ssid;
+  if (FindNetwork(guid) != networks_.end()) {
+    *error = kErrorInvalidData;
+    return;
+  }
+  network_properties_.SetWithoutPathExpansion(guid,
+                                              properties.release());
+  *network_guid = guid;
+}
+
+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;
+  }
+
+  if (networks_.empty())
+    UpdateNetworks();
+
+  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() {
+  DVLOG(1) << "*** RequestNetworkScan";
+  UpdateNetworks();
+}
+
+void WiFiServiceMac::StartConnect(const std::string& network_guid,
+                                  std::string* error) {
+  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);

[tbarzic, 2014/01/28 02:05:03]

can this just return now?

[mef, 2014/01/28 14:39:36]

Done.

+    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) {
+    // System can't find the network, remove it from the |networks_| and notify
+    // observers.
+    NetworkList::iterator it = FindNetwork(connected_network_guid);
+    if (it != networks_.end()) {
+      networks_.erase(it);
+      // Notify observers that list has changed.
+      NotifyNetworkListChanged(networks_);
+    }
+
+    *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);
+  }
+
+  // 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]) {
+      NSInteger error_code = [ns_error code];
+      if (error_code != kCWTimeoutErr && error_code != kCWInvalidPMKErr) {
+        break;
+      }
+    }
+  }
+  CheckError(ns_error, kErrorAssociateToNetwork, error);
+}
+
+void WiFiServiceMac::StartDisconnect(const std::string& network_guid,
+                                     std::string* error) {
+  DVLOG(1) << "*** StartDisconnect: " << network_guid;
+
+  if (network_guid == GUIDFromSSID([interface_ ssid])) {
+    // Power-cycle the interface to disconnect from current network and connect
+    // to default network.
+    NSError* ns_error = nil;
+    [interface_ setPower:NO error:&ns_error];
+    CheckError(ns_error, kErrorAssociateToNetwork, error);
+    [interface_ setPower:YES error:&ns_error];
+    CheckError(ns_error, kErrorAssociateToNetwork, error);
+  } else {
+    *error = kErrorNotConnected;
+  }
+}
+
+void WiFiServiceMac::SetEventObservers(
+    scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
+    const NetworkGuidListCallback& networks_changed_observer,
+    const NetworkGuidListCallback& network_list_changed_observer) {
+  message_loop_proxy_.swap(message_loop_proxy);
+  networks_changed_observer_ = networks_changed_observer;
+  network_list_changed_observer_ = network_list_changed_observer;
+
+  // Remove previous OS notifications observer.
+  if (wlan_observer_) {

[tbarzic, 2014/01/28 02:05:03]

I'd rather do a CHECK (as calling SetEventObservers twice would break the
expectation of the first observer).
But if you want to keep it this way, that's OK.

[mef, 2014/01/28 14:39:36]

Ok

+    [[NSNotificationCenter defaultCenter] removeObserver:wlan_observer_];
+    wlan_observer_ = nil;
+  }
+
+  // Subscribe to OS notifications.
+  if (!networks_changed_observer_.is_null()) {
+    void (^ns_observer) (NSNotification* notification) =
+        ^(NSNotification* notification) {
+            DVLOG(1) << "Received CWSSIDDidChangeNotification";
+            task_runner_->PostTask(
+                FROM_HERE,
+                base::Bind(&WiFiServiceMac::OnWlanObserverNotification,
+                           base::Unretained(this)));
+    };
+
+    wlan_observer_ = [[NSNotificationCenter defaultCenter]
+        addObserverForName:CWSSIDDidChangeNotification
+                    object:nil
+                     queue:nil
+                usingBlock:ns_observer];
+  }
+}
+
+void WiFiServiceMac::OnNetworkChangeNotification() {
+  OnWlanObserverNotification();
+}
+
+std::string WiFiServiceMac::GetNetworkConnectionState(
+    const std::string& network_guid) const {
+  if (network_guid != GUIDFromSSID([interface_ ssid]))
+    return onc::connection_state::kNotConnected;
+
+  // 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)) {
+    // Network is reachable, report is as |kConnected|.
+    return onc::connection_state::kConnected;
+  }
+  // Network is not reachable yet, so it must be |kConnecting|.
+  return onc::connection_state::kConnecting;
+}
+
+void WiFiServiceMac::UpdateNetworks() {
+  NSError* ns_error = nil;
+  NSSet* cw_networks = [interface_ scanForNetworksWithName:nil
+                                                     error:&ns_error];
+
+  if (ns_error != nil)
+    return;
+
+  std::map<std::string, NetworkProperties*> network_properties_map;
+  networks_.clear();
+
+  // There is one |cw_network| per BSS in |cw_networks|, so go through the set
+  // and combine them, paying attention to supported frequencies.
+  for (CWNetwork* cw_network in cw_networks) {
+    NetworkProperties network_properties;

[tbarzic, 2014/01/28 02:05:03]

if the network is connected, you should make sure network_properties contain the
properties for the connected BSS.

[mef, 2014/01/28 14:39:36]

Done.

+    NetworkPropertiesFromCWNetwork(cw_network, &network_properties);
+
+    if (network_properties_map.find(network_properties.guid) ==

[tbarzic, 2014/01/28 02:05:03]

you could check this before NetworkPropertiesFromCWNetwork, and if properties
are found, pass the pointer to thoes to NetworkPropertiesFromCWNetwork (that way
it would be easier to control if existing properties should be overwritten or
not).

[mef, 2014/01/28 14:39:36]

Done.

+            network_properties_map.end()) {
+      networks_.push_back(network_properties);
+      network_properties_map[network_properties.guid] = &networks_.back();
+    } else {
+      NetworkProperties* existing = network_properties_map.at(
+          network_properties.guid);
+      existing->frequency_set.insert(*network_properties.frequency_set.begin());
+    }
+  }
+  // Sort networks, so connected/connecting is up front.
+  networks_.sort(NetworkProperties::OrderByType);
+  // Notify observers that list has changed.
+  NotifyNetworkListChanged(networks_);
+}
+
+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 {
+  std::string network_guid = GUIDFromSSID([network ssid]);
+
+  properties->connection_state = GetNetworkConnectionState(network_guid);
+  properties->ssid = base::SysNSStringToUTF8([network ssid]);
+  properties->name = properties->ssid;
+  properties->guid = network_guid;
+  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;
+}
+
+WiFiService::NetworkList::iterator WiFiServiceMac::FindNetwork(
+    const std::string& network_guid) {
+  for (NetworkList::iterator it = networks_.begin();
+       it != networks_.end();
+       ++it) {
+    if (it->guid == network_guid)
+      return it;
+  }
+  return networks_.end();
+}
+
+void WiFiServiceMac::OnWlanObserverNotification() {
+  std::string connected_network_guid = GUIDFromSSID([interface_ ssid]);
+  DVLOG(1) << " *** Got Notification: " << connected_network_guid;
+  // Connected network has changed, mark previous one disconnected.
+  if (connected_network_guid != connected_network_guid_) {
+    // Update connection_state of newly connected network.
+    NetworkList::iterator it = FindNetwork(connected_network_guid_);
+    if (it != networks_.end()) {
+      it->connection_state = onc::connection_state::kNotConnected;
+      NotifyNetworkChanged(connected_network_guid_);
+    }
+    connected_network_guid_ = connected_network_guid;
+  }
+
+  if (!connected_network_guid.empty()) {
+    // Update connection_state of newly connected network.
+    NetworkList::iterator it = FindNetwork(connected_network_guid);
+    if (it != networks_.end()) {
+      it->connection_state = GetNetworkConnectionState(connected_network_guid);
+    } else {
+      // Can't find |connected_network_guid| in |networks_|, try to update it.
+      UpdateNetworks();
+    }
+    // Notify that network is connecting.
+    NotifyNetworkChanged(connected_network_guid);
+    // Further network change notification will be sent by detector.
+  }
+}
+
+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 (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