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;
+
+ 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;
+
+  // Convert s|CWSecurityMode| into onc::wifi::k{WPA|WEP}* security constant.
+  std::string SecurityFromCWSecurityMode(CWSecurityMode security) const;
+
+  // Waits up to |kMaxAttempts| with |kAttemptDelayMs| delay for connection to
+  // network with |network_guid|. Notifies that |NetworkChanged| upon success.
+  void WaitForNetworkConnect(const std::string& network_guid, int attempt);
+
+  // 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).
+  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_;
+  // 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() : wlan_observer_(nil) {
+}
+
+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()) {
+    *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() {
+  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);
+    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_) {
+    [[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) {
+            task_runner_->PostTask(
+                FROM_HERE,
+                base::Bind(&WiFiServiceMac::OnWlanObserverNotification,
+                           base::Unretained(this)));
+    };
+
+    wlan_observer_ = [[NSNotificationCenter defaultCenter]
+        addObserverForName:kCWSSIDDidChangeNotification
+                    object:nil
+                     queue:nil
+                usingBlock:ns_observer];
+  }
+}
+
+void WiFiServiceMac::WaitForNetworkConnect(const std::string& network_guid,
+                                           int attempt) {
+  // If network didn't get connected in |kMaxAttempts|, then stop waiting.
+  if (attempt > kConnectionCheckMaxAttempts) {
+    DLOG(ERROR) << kConnectionCheckMaxAttempts
+                << " attempts exceeded waiting for connect to "
+                << network_guid;
+    return;
+  }
+
+  if (GetNetworkConnectionState(network_guid) ==
+          onc::connection_state::kConnected) {
+    DVLOG(1) << "WiFi Connected, Reachable: " << network_guid;
+    NotifyNetworkChanged(network_guid);
+  } else {
+    // 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));
+  }
+}
+
+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;
+    NetworkPropertiesFromCWNetwork(cw_network, &network_properties);
+
+    if (network_properties_map.find(network_properties.guid) ==
+            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;
+  // There are 2 notifications for every network switch:
+  //  1. When old WLAN is disconnected, |connected_network_guid| is empty.
+  //  2. When new WLAN is connected, |connected_network_guid| is new 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 {
+    // 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();

[tbarzic, 2014/01/16 19:41:49]

will this find a connected hidden network? Should this be more targeted (e.g.
UpdateNetwork(ssid), which does general scan when ssid.empty())

[mef, 2014/01/16 23:42:48]

UpdateNetworks() will not see the hidden network, however StartConnect() uses
scanForNetworksWithName:SSIDFromGUID(network_guid), which should fine one if it
is around (to be verified).

+    }
+    // Notify that network is connecting.
+    NotifyNetworkChanged(connected_network_guid);
+    // Start waiting for network connection to complete.
+    if (!networks_changed_observer_.is_null())
+      WaitForNetworkConnect(connected_network_guid, 0);
+  }
+}
+
+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