1// Copyright 2015 The Android Open Source Project
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//      http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#include "buffet/shill_client.h"
16
17#include <set>
18
19#include <base/message_loop/message_loop.h>
20#include <base/stl_util.h>
21#include <brillo/any.h>
22#include <brillo/errors/error.h>
23#include <brillo/variant_dictionary.h>
24#include <dbus/shill/dbus-constants.h>
25#include <weave/enum_to_string.h>
26
27#include "buffet/ap_manager_client.h"
28#include "buffet/socket_stream.h"
29#include "buffet/weave_error_conversion.h"
30
31using brillo::Any;
32using brillo::VariantDictionary;
33using dbus::ObjectPath;
34using org::chromium::flimflam::DeviceProxy;
35using org::chromium::flimflam::ServiceProxy;
36using std::map;
37using std::set;
38using std::string;
39using std::vector;
40using weave::EnumToString;
41using weave::provider::Network;
42
43namespace buffet {
44
45namespace {
46
47void IgnoreDetachEvent() {}
48
49bool GetStateForService(ServiceProxy* service, string* state) {
50  CHECK(service) << "|service| was nullptr in GetStateForService()";
51  VariantDictionary properties;
52  if (!service->GetProperties(&properties, nullptr)) {
53    LOG(WARNING) << "Failed to read properties from service.";
54    return false;
55  }
56  auto property_it = properties.find(shill::kStateProperty);
57  if (property_it == properties.end()) {
58    LOG(WARNING) << "No state found in service properties.";
59    return false;
60  }
61  string new_state = property_it->second.TryGet<string>();
62  if (new_state.empty()) {
63    LOG(WARNING) << "Invalid state value.";
64    return false;
65  }
66  *state = new_state;
67  return true;
68}
69
70Network::State ShillServiceStateToNetworkState(const string& state) {
71  // TODO(wiley) What does "unconfigured" mean in a world with multiple sets
72  //             of WiFi credentials?
73  // TODO(wiley) Detect disabled devices, update state appropriately.
74  if ((state.compare(shill::kStateReady) == 0) ||
75      (state.compare(shill::kStatePortal) == 0) ||
76      (state.compare(shill::kStateOnline) == 0)) {
77    return Network::State::kOnline;
78  }
79  if ((state.compare(shill::kStateAssociation) == 0) ||
80      (state.compare(shill::kStateConfiguration) == 0)) {
81    return Network::State::kConnecting;
82  }
83  if ((state.compare(shill::kStateFailure) == 0) ||
84      (state.compare(shill::kStateActivationFailure) == 0)) {
85    // TODO(wiley) Get error information off the service object.
86    return Network::State::kError;
87  }
88  if ((state.compare(shill::kStateIdle) == 0) ||
89      (state.compare(shill::kStateOffline) == 0) ||
90      (state.compare(shill::kStateDisconnect) == 0)) {
91    return Network::State::kOffline;
92  }
93  LOG(WARNING) << "Unknown state found: '" << state << "'";
94  return Network::State::kOffline;
95}
96
97}  // namespace
98
99ShillClient::ShillClient(const scoped_refptr<dbus::Bus>& bus,
100                         const set<string>& device_whitelist,
101                         bool disable_xmpp)
102    : bus_{bus},
103      manager_proxy_{bus_},
104      device_whitelist_{device_whitelist},
105      disable_xmpp_{disable_xmpp},
106      ap_manager_client_{new ApManagerClient(bus)} {
107  manager_proxy_.RegisterPropertyChangedSignalHandler(
108      base::Bind(&ShillClient::OnManagerPropertyChange,
109                 weak_factory_.GetWeakPtr()),
110      base::Bind(&ShillClient::OnManagerPropertyChangeRegistration,
111                 weak_factory_.GetWeakPtr()));
112  auto owner_changed_cb = base::Bind(&ShillClient::OnShillServiceOwnerChange,
113                                     weak_factory_.GetWeakPtr());
114  bus_->GetObjectProxy(shill::kFlimflamServiceName, ObjectPath{"/"})
115      ->SetNameOwnerChangedCallback(owner_changed_cb);
116
117  Init();
118}
119
120ShillClient::~ShillClient() {}
121
122void ShillClient::Init() {
123  VLOG(2) << "ShillClient::Init();";
124  CleanupConnectingService();
125  devices_.clear();
126  connectivity_state_ = Network::State::kOffline;
127  VariantDictionary properties;
128  if (!manager_proxy_.GetProperties(&properties, nullptr)) {
129    LOG(ERROR) << "Unable to get properties from Manager, waiting for "
130                  "Manager to come back online.";
131    return;
132  }
133  auto it = properties.find(shill::kDevicesProperty);
134  CHECK(it != properties.end()) << "shill should always publish a device list.";
135  OnManagerPropertyChange(shill::kDevicesProperty, it->second);
136}
137
138void ShillClient::Connect(const string& ssid,
139                          const string& passphrase,
140                          const weave::DoneCallback& callback) {
141  LOG(INFO) << "Connecting to WiFi network: " << ssid;
142  if (connecting_service_) {
143    weave::ErrorPtr error;
144    weave::Error::AddTo(&error, FROM_HERE, "busy",
145                        "Already connecting to WiFi network");
146    base::MessageLoop::current()->PostTask(
147        FROM_HERE, base::Bind(callback, base::Passed(&error)));
148    return;
149  }
150  CleanupConnectingService();
151  VariantDictionary service_properties;
152  service_properties[shill::kTypeProperty] = Any{string{shill::kTypeWifi}};
153  service_properties[shill::kSSIDProperty] = Any{ssid};
154  if (passphrase.empty()) {
155    service_properties[shill::kSecurityProperty] = Any{shill::kSecurityNone};
156  } else {
157    service_properties[shill::kPassphraseProperty] = Any{passphrase};
158    service_properties[shill::kSecurityProperty] = Any{shill::kSecurityPsk};
159  }
160  service_properties[shill::kSaveCredentialsProperty] = Any{true};
161  service_properties[shill::kAutoConnectProperty] = Any{true};
162  ObjectPath service_path;
163  brillo::ErrorPtr brillo_error;
164  if (!manager_proxy_.ConfigureService(service_properties, &service_path,
165                                       &brillo_error) ||
166      !manager_proxy_.RequestScan(shill::kTypeWifi, &brillo_error)) {
167    weave::ErrorPtr weave_error;
168    ConvertError(*brillo_error, &weave_error);
169    base::MessageLoop::current()->PostTask(
170        FROM_HERE, base::Bind(callback, base::Passed(&weave_error)));
171    return;
172  }
173  connecting_service_.reset(new ServiceProxy{bus_, service_path});
174  connecting_service_->Connect(nullptr);
175  connect_done_callback_ = callback;
176  connecting_service_->RegisterPropertyChangedSignalHandler(
177      base::Bind(&ShillClient::OnServicePropertyChange,
178                 weak_factory_.GetWeakPtr(), service_path),
179      base::Bind(&ShillClient::OnServicePropertyChangeRegistration,
180                 weak_factory_.GetWeakPtr(), service_path));
181  base::MessageLoop::current()->PostDelayedTask(
182      FROM_HERE, base::Bind(&ShillClient::ConnectToServiceError,
183                            weak_factory_.GetWeakPtr(), connecting_service_),
184      base::TimeDelta::FromMinutes(1));
185}
186
187void ShillClient::ConnectToServiceError(
188    std::shared_ptr<org::chromium::flimflam::ServiceProxy> connecting_service) {
189  if (connecting_service != connecting_service_ ||
190      connect_done_callback_.is_null()) {
191    return;
192  }
193  std::string error = have_called_connect_ ? connecting_service_error_
194                                           : shill::kErrorOutOfRange;
195  if (error.empty())
196    error = shill::kErrorInternal;
197  OnErrorChangeForConnectingService(error);
198}
199
200Network::State ShillClient::GetConnectionState() const {
201  return connectivity_state_;
202}
203
204void ShillClient::StartAccessPoint(const std::string& ssid) {
205  LOG(INFO) << "Starting Soft AP: " << ssid;
206  ap_manager_client_->Start(ssid);
207}
208
209void ShillClient::StopAccessPoint() {
210  LOG(INFO) << "Stopping Soft AP";
211  ap_manager_client_->Stop();
212}
213
214void ShillClient::AddConnectionChangedCallback(
215    const ConnectionChangedCallback& listener) {
216  connectivity_listeners_.push_back(listener);
217}
218
219bool ShillClient::IsMonitoredDevice(DeviceProxy* device) {
220  if (device_whitelist_.empty()) {
221    return true;
222  }
223  VariantDictionary device_properties;
224  if (!device->GetProperties(&device_properties, nullptr)) {
225    LOG(ERROR) << "Devices without properties aren't whitelisted.";
226    return false;
227  }
228  auto it = device_properties.find(shill::kInterfaceProperty);
229  if (it == device_properties.end()) {
230    LOG(ERROR) << "Failed to find interface property in device properties.";
231    return false;
232  }
233  return ContainsKey(device_whitelist_, it->second.TryGet<string>());
234}
235
236void ShillClient::OnShillServiceOwnerChange(const string& old_owner,
237                                            const string& new_owner) {
238  VLOG(1) << "Shill service owner name changed to '" << new_owner << "'";
239  if (new_owner.empty()) {
240    CleanupConnectingService();
241    devices_.clear();
242    connectivity_state_ = Network::State::kOffline;
243  } else {
244    Init();  // New service owner means shill reset!
245  }
246}
247
248void ShillClient::OnManagerPropertyChangeRegistration(const string& interface,
249                                                      const string& signal_name,
250                                                      bool success) {
251  VLOG(3) << "Registered ManagerPropertyChange handler.";
252  CHECK(success) << "privetd requires Manager signals.";
253  VariantDictionary properties;
254  if (!manager_proxy_.GetProperties(&properties, nullptr)) {
255    LOG(ERROR) << "Unable to get properties from Manager, waiting for "
256                  "Manager to come back online.";
257    return;
258  }
259  auto it = properties.find(shill::kDevicesProperty);
260  CHECK(it != properties.end()) << "Shill should always publish a device list.";
261  OnManagerPropertyChange(shill::kDevicesProperty, it->second);
262}
263
264void ShillClient::OnManagerPropertyChange(const string& property_name,
265                                          const Any& property_value) {
266  if (property_name != shill::kDevicesProperty) {
267    return;
268  }
269  bool update_connectivity = false;
270  VLOG(3) << "Manager's device list has changed.";
271  // We're going to remove every device we haven't seen in the update.
272  set<ObjectPath> device_paths_to_remove;
273  for (const auto& kv : devices_) {
274    device_paths_to_remove.insert(kv.first);
275  }
276  for (const auto& device_path : property_value.TryGet<vector<ObjectPath>>()) {
277    if (!device_path.IsValid()) {
278      LOG(ERROR) << "Ignoring invalid device path in Manager's device list.";
279      return;
280    }
281    auto it = devices_.find(device_path);
282    if (it != devices_.end()) {
283      // Found an existing proxy.  Since the whitelist never changes,
284      // this still a valid device.
285      device_paths_to_remove.erase(device_path);
286      continue;
287    }
288    std::unique_ptr<DeviceProxy> device{new DeviceProxy{bus_, device_path}};
289    if (!IsMonitoredDevice(device.get())) {
290      continue;
291    }
292    VLOG(3) << "Creating device proxy at " << device_path.value();
293    devices_[device_path].device = std::move(device);
294    update_connectivity = true;
295    devices_[device_path].device->RegisterPropertyChangedSignalHandler(
296        base::Bind(&ShillClient::OnDevicePropertyChange,
297                   weak_factory_.GetWeakPtr(), device_path),
298        base::Bind(&ShillClient::OnDevicePropertyChangeRegistration,
299                   weak_factory_.GetWeakPtr(), device_path));
300  }
301  // Clean up devices/services related to removed devices.
302  for (const ObjectPath& device_path : device_paths_to_remove) {
303    devices_.erase(device_path);
304    update_connectivity = true;
305  }
306
307  if (update_connectivity)
308    UpdateConnectivityState();
309}
310
311void ShillClient::OnDevicePropertyChangeRegistration(
312    const ObjectPath& device_path,
313    const string& interface,
314    const string& signal_name,
315    bool success) {
316  VLOG(3) << "Registered DevicePropertyChange handler.";
317  auto it = devices_.find(device_path);
318  if (it == devices_.end()) {
319    return;
320  }
321  CHECK(success) << "Failed to subscribe to Device property changes.";
322  DeviceProxy* device = it->second.device.get();
323  VariantDictionary properties;
324  if (!device->GetProperties(&properties, nullptr)) {
325    LOG(WARNING) << "Failed to get device properties?";
326    return;
327  }
328  auto prop_it = properties.find(shill::kSelectedServiceProperty);
329  if (prop_it == properties.end()) {
330    LOG(WARNING) << "Failed to get device's selected service?";
331    return;
332  }
333  OnDevicePropertyChange(device_path, shill::kSelectedServiceProperty,
334                         prop_it->second);
335}
336
337void ShillClient::OnDevicePropertyChange(const ObjectPath& device_path,
338                                         const string& property_name,
339                                         const Any& property_value) {
340  // We only care about selected services anyway.
341  if (property_name != shill::kSelectedServiceProperty) {
342    return;
343  }
344  // If the device isn't our list of whitelisted devices, ignore it.
345  auto it = devices_.find(device_path);
346  if (it == devices_.end()) {
347    return;
348  }
349  DeviceState& device_state = it->second;
350  ObjectPath service_path{property_value.TryGet<ObjectPath>()};
351  if (!service_path.IsValid()) {
352    LOG(ERROR) << "Device at " << device_path.value()
353               << " selected invalid service path.";
354    return;
355  }
356  VLOG(3) << "Device at " << it->first.value() << " has selected service at "
357          << service_path.value();
358  bool removed_old_service{false};
359  if (device_state.selected_service) {
360    if (device_state.selected_service->GetObjectPath() == service_path) {
361      return;  // Spurious update?
362    }
363    device_state.selected_service.reset();
364    device_state.service_state = Network::State::kOffline;
365    removed_old_service = true;
366  }
367  const bool reuse_connecting_service =
368      service_path.value() != "/" && connecting_service_ &&
369      connecting_service_->GetObjectPath() == service_path;
370  if (reuse_connecting_service) {
371    device_state.selected_service = connecting_service_;
372    // When we reuse the connecting service, we need to make sure that our
373    // cached state is correct.  Normally, we do this by relying reading the
374    // state when our signal handlers finish registering, but this may have
375    // happened long in the past for the connecting service.
376    string state;
377    if (GetStateForService(connecting_service_.get(), &state)) {
378      device_state.service_state = ShillServiceStateToNetworkState(state);
379    } else {
380      LOG(WARNING) << "Failed to read properties from existing service "
381                      "on selection.";
382    }
383  } else if (service_path.value() != "/") {
384    // The device has selected a new service we haven't see before.
385    device_state.selected_service =
386        std::make_shared<ServiceProxy>(bus_, service_path);
387    device_state.selected_service->RegisterPropertyChangedSignalHandler(
388        base::Bind(&ShillClient::OnServicePropertyChange,
389                   weak_factory_.GetWeakPtr(), service_path),
390        base::Bind(&ShillClient::OnServicePropertyChangeRegistration,
391                   weak_factory_.GetWeakPtr(), service_path));
392  }
393
394  if (reuse_connecting_service || removed_old_service) {
395    UpdateConnectivityState();
396  }
397}
398
399void ShillClient::OnServicePropertyChangeRegistration(const ObjectPath& path,
400                                                      const string& interface,
401                                                      const string& signal_name,
402                                                      bool success) {
403  VLOG(3) << "OnServicePropertyChangeRegistration(" << path.value() << ");";
404  ServiceProxy* service{nullptr};
405  if (connecting_service_ && connecting_service_->GetObjectPath() == path) {
406    // Note that the connecting service might also be a selected service.
407    service = connecting_service_.get();
408    if (!success)
409      CleanupConnectingService();
410  } else {
411    for (const auto& kv : devices_) {
412      if (kv.second.selected_service &&
413          kv.second.selected_service->GetObjectPath() == path) {
414        service = kv.second.selected_service.get();
415        break;
416      }
417    }
418  }
419  if (service == nullptr || !success) {
420    return;  // A failure or success for a proxy we no longer care about.
421  }
422  VariantDictionary properties;
423  if (!service->GetProperties(&properties, nullptr)) {
424    return;
425  }
426  // Give ourselves property changed signals for the initial property
427  // values.
428  for (auto name : {shill::kStateProperty, shill::kSignalStrengthProperty,
429                    shill::kErrorProperty}) {
430    auto it = properties.find(name);
431    if (it != properties.end())
432      OnServicePropertyChange(path, name, it->second);
433  }
434}
435
436void ShillClient::OnServicePropertyChange(const ObjectPath& service_path,
437                                          const string& property_name,
438                                          const Any& property_value) {
439  VLOG(3) << "ServicePropertyChange(" << service_path.value() << ", "
440          << property_name << ", ...);";
441
442  bool is_connecting_service =
443      connecting_service_ &&
444      connecting_service_->GetObjectPath() == service_path;
445  if (property_name == shill::kStateProperty) {
446    const string state{property_value.TryGet<string>()};
447    if (state.empty()) {
448      VLOG(3) << "Invalid service state update.";
449      return;
450    }
451    VLOG(3) << "New service state=" << state;
452    OnStateChangeForSelectedService(service_path, state);
453    if (is_connecting_service)
454      OnStateChangeForConnectingService(state);
455  } else if (property_name == shill::kSignalStrengthProperty) {
456    VLOG(3) << "Signal strength=" << property_value.TryGet<uint8_t>();
457    if (is_connecting_service)
458      OnStrengthChangeForConnectingService(property_value.TryGet<uint8_t>());
459  } else if (property_name == shill::kErrorProperty) {
460    VLOG(3) << "Error=" << property_value.TryGet<std::string>();
461    if (is_connecting_service)
462      connecting_service_error_ = property_value.TryGet<std::string>();
463  }
464}
465
466void ShillClient::OnStateChangeForConnectingService(const string& state) {
467  switch (ShillServiceStateToNetworkState(state)) {
468    case Network::State::kOnline: {
469      auto callback = connect_done_callback_;
470      connect_done_callback_.Reset();
471      CleanupConnectingService();
472
473      if (!callback.is_null())
474        callback.Run(nullptr);
475      break;
476    }
477    case Network::State::kError: {
478      ConnectToServiceError(connecting_service_);
479      break;
480    }
481    case Network::State::kOffline:
482    case Network::State::kConnecting:
483      break;
484  }
485}
486
487void ShillClient::OnErrorChangeForConnectingService(const std::string& error) {
488  if (error.empty())
489    return;
490
491  auto callback = connect_done_callback_;
492  CleanupConnectingService();
493
494  weave::ErrorPtr weave_error;
495  weave::Error::AddTo(&weave_error, FROM_HERE, error,
496                      "Failed to connect to WiFi network");
497
498  if (!callback.is_null())
499    callback.Run(std::move(weave_error));
500}
501
502void ShillClient::OnStrengthChangeForConnectingService(
503    uint8_t signal_strength) {
504  if (signal_strength == 0 || have_called_connect_) {
505    return;
506  }
507  VLOG(1) << "Connecting service has signal. Calling Connect().";
508  have_called_connect_ = true;
509  // Failures here indicate that we've already connected,
510  // or are connecting, or some other very unexciting thing.
511  // Ignore all that, and rely on state changes to detect
512  // connectivity.
513  connecting_service_->Connect(nullptr);
514}
515
516void ShillClient::OnStateChangeForSelectedService(
517    const ObjectPath& service_path,
518    const string& state) {
519  // Find the device/service pair responsible for this update
520  VLOG(3) << "State for potentially selected service " << service_path.value()
521          << " have changed to " << state;
522  for (auto& kv : devices_) {
523    if (kv.second.selected_service &&
524        kv.second.selected_service->GetObjectPath() == service_path) {
525      VLOG(3) << "Updated cached connection state for selected service.";
526      kv.second.service_state = ShillServiceStateToNetworkState(state);
527      UpdateConnectivityState();
528      return;
529    }
530  }
531}
532
533void ShillClient::UpdateConnectivityState() {
534  // Update the connectivity state of the device by picking the
535  // state of the currently most connected selected service.
536  Network::State new_connectivity_state{Network::State::kOffline};
537  for (const auto& kv : devices_) {
538    if (kv.second.service_state > new_connectivity_state) {
539      new_connectivity_state = kv.second.service_state;
540    }
541  }
542  VLOG(1) << "Connectivity changed: " << EnumToString(connectivity_state_)
543          << " -> " << EnumToString(new_connectivity_state);
544  // Notify listeners even if state changed to the same value. Listeners may
545  // want to handle this event.
546  connectivity_state_ = new_connectivity_state;
547  // We may call UpdateConnectivityState whenever we mutate a data structure
548  // such that our connectivity status could change.  However, we don't want
549  // to allow people to call into ShillClient while some other operation is
550  // underway.  Therefore, call our callbacks later, when we're in a good
551  // state.
552  base::MessageLoop::current()->PostTask(
553      FROM_HERE, base::Bind(&ShillClient::NotifyConnectivityListeners,
554                            weak_factory_.GetWeakPtr(),
555                            GetConnectionState() == Network::State::kOnline));
556}
557
558void ShillClient::NotifyConnectivityListeners(bool am_online) {
559  VLOG(3) << "Notifying connectivity listeners that online=" << am_online;
560  for (const auto& listener : connectivity_listeners_)
561    listener.Run();
562}
563
564void ShillClient::CleanupConnectingService() {
565  if (connecting_service_) {
566    connecting_service_->ReleaseObjectProxy(base::Bind(&IgnoreDetachEvent));
567    connecting_service_.reset();
568  }
569  connect_done_callback_.Reset();
570  have_called_connect_ = false;
571}
572
573void ShillClient::OpenSslSocket(const std::string& host,
574                                uint16_t port,
575                                const OpenSslSocketCallback& callback) {
576  if (disable_xmpp_)
577    return;
578  std::unique_ptr<weave::Stream> raw_stream{
579      SocketStream::ConnectBlocking(host, port)};
580  if (!raw_stream) {
581    brillo::ErrorPtr error;
582    brillo::errors::system::AddSystemError(&error, FROM_HERE, errno);
583    weave::ErrorPtr weave_error;
584    ConvertError(*error.get(), &weave_error);
585    base::MessageLoop::current()->PostTask(
586        FROM_HERE, base::Bind(callback, nullptr, base::Passed(&weave_error)));
587    return;
588  }
589
590  SocketStream::TlsConnect(std::move(raw_stream), host, callback);
591}
592
593}  // namespace buffet
594