scanning/scanner_impl.cpp

   1 /*
   2  * Copyright (C) 2016 The Android Open Source Project
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include "wificond/scanning/scanner_impl.h"
  18
  19 #include <string>
  20 #include <vector>
  21
  22 #include <android-base/logging.h>
  23
  24 #include "wificond/client_interface_impl.h"
  25 #include "wificond/scanning/scan_utils.h"
  26
  27 using android::binder::Status;
  28 using android::net::wifi::IPnoScanEvent;
  29 using android::net::wifi::IScanEvent;
  30 using android::sp;
  31 using com::android::server::wifi::wificond::NativeScanResult;
  32 using com::android::server::wifi::wificond::PnoSettings;
  33 using com::android::server::wifi::wificond::SingleScanSettings;
  34
  35 using std::string;
  36 using std::vector;
  37
  38 using namespace std::placeholders;
  39
  40 namespace android {
  41 namespace wificond {
  42
  43 ScannerImpl::ScannerImpl(uint32_t wiphy_index,
  44                          uint32_t interface_index,
  45                          const ScanCapabilities& scan_capabilities,
  46                          const WiphyFeatures& wiphy_features,
  47                          ClientInterfaceImpl* client_interface,
  48                          NetlinkUtils* netlink_utils,
  49                          ScanUtils* scan_utils)
  50     : valid_(true),
  51       scan_started_(false),
  52       pno_scan_started_(false),
  53       wiphy_index_(wiphy_index),
  54       interface_index_(interface_index),
  55       scan_capabilities_(scan_capabilities),
  56       wiphy_features_(wiphy_features),
  57       client_interface_(client_interface),
  58       netlink_utils_(netlink_utils),
  59       scan_utils_(scan_utils),
  60       scan_event_handler_(nullptr) {
  61   // Subscribe one-shot scan result notification from kernel.
  62   LOG(INFO) << "subscribe scan result for interface with index: "
  63             << (int)interface_index_;
  64   scan_utils_->SubscribeScanResultNotification(
  65       interface_index_,
  66       std::bind(&ScannerImpl::OnScanResultsReady,
  67                 this,
  68                 _1, _2, _3, _4));
  69   // Subscribe scheduled scan result notification from kernel.
  70   scan_utils_->SubscribeSchedScanResultNotification(
  71       interface_index_,
  72       std::bind(&ScannerImpl::OnSchedScanResultsReady,
  73                 this,
  74                 _1, _2));
  75 }
  76
  77 ScannerImpl::~ScannerImpl() {
  78 }
  79
  80 void ScannerImpl::Invalidate() {
  81   LOG(INFO) << "Unsubscribe scan result for interface with index: "
  82             << (int)interface_index_;
  83   scan_utils_->UnsubscribeScanResultNotification(interface_index_);
  84   scan_utils_->UnsubscribeSchedScanResultNotification(interface_index_);
  85 }
  86
  87 bool ScannerImpl::CheckIsValid() {
  88   if (!valid_) {
  89     LOG(DEBUG) << "Calling on a invalid scanner object."
  90                << "Underlying client interface object was destroyed.";
  91   }
  92   return valid_;
  93 }
  94
  95 Status ScannerImpl::getAvailable2gChannels(
  96     std::unique_ptr<vector<int32_t>>* out_frequencies) {
  97   if (!CheckIsValid()) {
  98     return Status::ok();
  99   }
 100   BandInfo band_info;
 101   if (!netlink_utils_->GetWiphyInfo(wiphy_index_,
 102                                &band_info,
 103                                &scan_capabilities_,
 104                                &wiphy_features_)) {
 105     LOG(ERROR) << "Failed to get wiphy info from kernel";
 106     out_frequencies->reset(nullptr);
 107     return Status::ok();
 108   }
 109
 110   out_frequencies->reset(new vector<int32_t>(band_info.band_2g.begin(),
 111                                              band_info.band_2g.end()));
 112   return Status::ok();
 113 }
 114
 115 Status ScannerImpl::getAvailable5gNonDFSChannels(
 116     std::unique_ptr<vector<int32_t>>* out_frequencies) {
 117   if (!CheckIsValid()) {
 118     return Status::ok();
 119   }
 120   BandInfo band_info;
 121   if (!netlink_utils_->GetWiphyInfo(wiphy_index_,
 122                                &band_info,
 123                                &scan_capabilities_,
 124                                &wiphy_features_)) {
 125     LOG(ERROR) << "Failed to get wiphy info from kernel";
 126     out_frequencies->reset(nullptr);
 127     return Status::ok();
 128   }
 129
 130   out_frequencies->reset(new vector<int32_t>(band_info.band_5g.begin(),
 131                                              band_info.band_5g.end()));
 132   return Status::ok();
 133 }
 134
 135 Status ScannerImpl::getAvailableDFSChannels(
 136     std::unique_ptr<vector<int32_t>>* out_frequencies) {
 137   if (!CheckIsValid()) {
 138     return Status::ok();
 139   }
 140   BandInfo band_info;
 141   if (!netlink_utils_->GetWiphyInfo(wiphy_index_,
 142                                &band_info,
 143                                &scan_capabilities_,
 144                                &wiphy_features_)) {
 145     LOG(ERROR) << "Failed to get wiphy info from kernel";
 146     out_frequencies->reset(nullptr);
 147     return Status::ok();
 148   }
 149
 150   out_frequencies->reset(new vector<int32_t>(band_info.band_dfs.begin(),
 151                                              band_info.band_dfs.end()));
 152   return Status::ok();
 153 }
 154
 155 Status ScannerImpl::getScanResults(vector<NativeScanResult>* out_scan_results) {
 156   if (!CheckIsValid()) {
 157     return Status::ok();
 158   }
 159   if (!scan_utils_->GetScanResult(interface_index_, out_scan_results)) {
 160     LOG(ERROR) << "Failed to get scan results via NL80211";
 161   }
 162   return Status::ok();
 163 }
 164
 165 Status ScannerImpl::scan(const SingleScanSettings& scan_settings,
 166                          bool* out_success) {
 167   if (!CheckIsValid()) {
 168     return Status::ok();
 169   }
 170
 171   if (scan_started_) {
 172     LOG(WARNING) << "Scan already started";
 173   }
 174   // Only request MAC address randomization when station is not associated.
 175   bool request_random_mac =  wiphy_features_.supports_random_mac_oneshot_scan &&
 176       !client_interface_->IsAssociated();
 177
 178   // Initialize it with an empty ssid for a wild card scan.
 179   vector<vector<uint8_t>> ssids = {{}};
 180   for (auto& network : scan_settings.hidden_networks_) {
 181     if (ssids.size() + 1 > scan_capabilities_.max_num_scan_ssids) {
 182       LOG(WARNING) << "Skip scan ssid for single scan: "
 183                    << string(network.ssid_.begin(), network.ssid_.end());
 184       continue;
 185     }
 186     ssids.push_back(network.ssid_);
 187   }
 188
 189   vector<uint32_t> freqs;
 190   for (auto& channel : scan_settings.channel_settings_) {
 191     freqs.push_back(channel.frequency_);
 192   }
 193
 194   if (!scan_utils_->Scan(interface_index_, request_random_mac, ssids, freqs)) {
 195     *out_success = false;
 196     return Status::ok();
 197   }
 198   scan_started_ = true;
 199   *out_success = true;
 200   return Status::ok();
 201 }
 202
 203 Status ScannerImpl::startPnoScan(const PnoSettings& pno_settings,
 204                                  bool* out_success) {
 205   if (!CheckIsValid()) {
 206     return Status::ok();
 207   }
 208   if (pno_scan_started_) {
 209     LOG(WARNING) << "Pno scan already started";
 210   }
 211   // An empty ssid for a wild card scan.
 212   vector<vector<uint8_t>> scan_ssids = {{}};
 213   vector<vector<uint8_t>> match_ssids;
 214   // Empty frequency list: scan all frequencies.
 215   vector<uint32_t> freqs;
 216
 217   for (auto& network : pno_settings.pno_networks_) {
 218     // Add hidden network ssid.
 219     if (network.is_hidden_) {
 220       if (scan_ssids.size() + 1 > scan_capabilities_.max_num_sched_scan_ssids) {
 221         LOG(WARNING) << "Skip scan ssid for pno scan: "
 222                      << string(network.ssid_.begin(), network.ssid_.end());
 223         continue;
 224       }
 225       scan_ssids.push_back(network.ssid_);
 226     }
 227
 228     if (match_ssids.size() + 1 > scan_capabilities_.max_match_sets) {
 229       LOG(WARNING) << "Skip match ssid for pno scan: "
 230                    << string(network.ssid_.begin(), network.ssid_.end());
 231       continue;
 232     }
 233     match_ssids.push_back(network.ssid_);
 234   }
 235
 236   // Only request MAC address randomization when station is not associated.
 237   bool request_random_mac = wiphy_features_.supports_random_mac_sched_scan &&
 238       !client_interface_->IsAssociated();
 239
 240   if (!scan_utils_->StartScheduledScan(interface_index_,
 241                                        pno_settings.interval_ms_,
 242                                        // TODO: honor both rssi thresholds.
 243                                        pno_settings.min_2g_rssi_,
 244                                        request_random_mac,
 245                                        scan_ssids,
 246                                        match_ssids,
 247                                        freqs)) {
 248     *out_success = false;
 249     LOG(ERROR) << "Failed to start scheduled scan";
 250     return Status::ok();
 251   }
 252   pno_scan_started_ = true;
 253   *out_success = true;
 254   return Status::ok();
 255 }
 256
 257 Status ScannerImpl::stopPnoScan(bool* out_success) {
 258   if (!CheckIsValid()) {
 259     return Status::ok();
 260   }
 261
 262   if (!pno_scan_started_) {
 263     LOG(WARNING) << "No pno scan started";
 264   }
 265   if (!scan_utils_->StopScheduledScan(interface_index_)) {
 266     *out_success = false;
 267     return Status::ok();
 268   }
 269   pno_scan_started_ = false;
 270   *out_success = true;
 271   return Status::ok();
 272 }
 273
 274 Status ScannerImpl::subscribeScanEvents(const sp<IScanEvent>& handler) {
 275   if (!CheckIsValid()) {
 276     return Status::ok();
 277   }
 278
 279   if (scan_event_handler_ != nullptr) {
 280     LOG(ERROR) << "Found existing scan events subscriber."
 281                << " This subscription request will unsubscribe it";
 282   }
 283   scan_event_handler_ = handler;
 284   return Status::ok();
 285 }
 286
 287 Status ScannerImpl::unsubscribeScanEvents() {
 288   scan_event_handler_ = nullptr;
 289   return Status::ok();
 290 }
 291
 292
 293 Status ScannerImpl::subscribePnoScanEvents(const sp<IPnoScanEvent>& handler) {
 294   if (!CheckIsValid()) {
 295     return Status::ok();
 296   }
 297
 298   if (pno_scan_event_handler_ != nullptr) {
 299     LOG(ERROR) << "Found existing pno scan events subscriber."
 300                << " This subscription request will unsubscribe it";
 301   }
 302   pno_scan_event_handler_ = handler;
 303
 304   return Status::ok();
 305 }
 306
 307 Status ScannerImpl::unsubscribePnoScanEvents() {
 308   pno_scan_event_handler_ = nullptr;
 309   return Status::ok();
 310 }
 311
 312 void ScannerImpl::OnScanResultsReady(
 313     uint32_t interface_index,
 314     bool aborted,
 315     vector<vector<uint8_t>>& ssids,
 316     vector<uint32_t>& frequencies) {
 317   LOG(INFO) << "Received scan result notification from kernel.";
 318   scan_started_ = false;
 319   if (scan_event_handler_ != nullptr) {
 320     // TODO: Pass other parameters back once we find framework needs them.
 321     if (aborted) {
 322       LOG(WARNING) << "Scan aborted";
 323       scan_event_handler_->OnScanFailed();
 324     } else {
 325       scan_event_handler_->OnScanResultReady();
 326     }
 327   } else {
 328     LOG(WARNING) << "No scan event handler found.";
 329   }
 330 }
 331
 332 void ScannerImpl::OnSchedScanResultsReady(uint32_t interface_index,
 333                                           bool scan_stopped) {
 334   if (pno_scan_event_handler_ != nullptr) {
 335     if (scan_stopped) {
 336       // If |pno_scan_started_| is false.
 337       // This stop notification might result from our own request.
 338       // See the document for NL80211_CMD_SCHED_SCAN_STOPPED in nl80211.h.
 339       if (pno_scan_started_) {
 340         pno_scan_event_handler_->OnPnoScanFailed();
 341       }
 342       pno_scan_started_ = false;
 343     } else {
 344       pno_scan_event_handler_->OnPnoNetworkFound();
 345     }
 346   }
 347 }
 348
 349 }  // namespace wificond
 350 }  // namespace android