1 /*
2  * Copyright (C) 2010 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 #ifndef ANDROID_SENSOR_SERVICE_H
18 #define ANDROID_SENSOR_SERVICE_H
19 
20 #include "SensorList.h"
21 #include "RecentEventLogger.h"
22 
23 #include <binder/AppOpsManager.h>
24 #include <binder/BinderService.h>
25 #include <binder/IUidObserver.h>
26 #include <cutils/compiler.h>
27 #include <cutils/multiuser.h>
28 #include <sensor/ISensorServer.h>
29 #include <sensor/ISensorEventConnection.h>
30 #include <sensor/Sensor.h>
31 #include "android/hardware/BnSensorPrivacyListener.h"
32 
33 #include <utils/AndroidThreads.h>
34 #include <utils/KeyedVector.h>
35 #include <utils/Looper.h>
36 #include <utils/SortedVector.h>
37 #include <utils/String8.h>
38 #include <utils/Vector.h>
39 #include <utils/threads.h>
40 
41 #include <stdint.h>
42 #include <sys/types.h>
43 #include <unordered_map>
44 #include <unordered_set>
45 
46 #if __clang__
47 // Clang warns about SensorEventConnection::dump hiding BBinder::dump. The cause isn't fixable
48 // without changing the API, so let's tell clang this is indeed intentional.
49 #pragma clang diagnostic ignored "-Woverloaded-virtual"
50 #endif
51 
52 // ---------------------------------------------------------------------------
53 #define IGNORE_HARDWARE_FUSION  false
54 #define DEBUG_CONNECTIONS   false
55 // Max size is 100 KB which is enough to accept a batch of about 1000 events.
56 #define MAX_SOCKET_BUFFER_SIZE_BATCHED (100 * 1024)
57 // For older HALs which don't support batching, use a smaller socket buffer size.
58 #define SOCKET_BUFFER_SIZE_NON_BATCHED (4 * 1024)
59 
60 #define SENSOR_REGISTRATIONS_BUF_SIZE 200
61 
62 namespace android {
63 // ---------------------------------------------------------------------------
64 class SensorInterface;
65 
66 class SensorService :
67         public BinderService<SensorService>,
68         public BnSensorServer,
69         protected Thread
70 {
71     // nested class/struct for internal use
72     class SensorEventConnection;
73     class SensorDirectConnection;
74 
75 public:
76     void cleanupConnection(SensorEventConnection* connection);
77     void cleanupConnection(SensorDirectConnection* c);
78 
79     status_t enable(const sp<SensorEventConnection>& connection, int handle,
80                     nsecs_t samplingPeriodNs,  nsecs_t maxBatchReportLatencyNs, int reservedFlags,
81                     const String16& opPackageName);
82 
83     status_t disable(const sp<SensorEventConnection>& connection, int handle);
84 
85     status_t setEventRate(const sp<SensorEventConnection>& connection, int handle, nsecs_t ns,
86                           const String16& opPackageName);
87 
88     status_t flushSensor(const sp<SensorEventConnection>& connection,
89                          const String16& opPackageName);
90 
91 
92     virtual status_t shellCommand(int in, int out, int err, Vector<String16>& args);
93 
94 private:
95     friend class BinderService<SensorService>;
96 
97     // nested class/struct for internal use
98     class SensorRecord;
99     class SensorEventAckReceiver;
100     class SensorRegistrationInfo;
101 
102     // If accessing a sensor we need to make sure the UID has access to it. If
103     // the app UID is idle then it cannot access sensors and gets no trigger
104     // events, no on-change events, flush event behavior does not change, and
105     // recurring events are the same as the first one delivered in idle state
106     // emulating no sensor change. As soon as the app UID transitions to an
107     // active state we will start reporting events as usual and vise versa. This
108     // approach transparently handles observing sensors while the app UID transitions
109     // between idle/active state avoiding to get stuck in a state receiving sensor
110     // data while idle or not receiving sensor data while active.
111     class UidPolicy : public BnUidObserver {
112         public:
UidPolicy(wp<SensorService> service)113             explicit UidPolicy(wp<SensorService> service)
114                     : mService(service) {}
115             void registerSelf();
116             void unregisterSelf();
117 
118             bool isUidActive(uid_t uid);
119 
120             void onUidGone(uid_t uid, bool disabled);
121             void onUidActive(uid_t uid);
122             void onUidIdle(uid_t uid, bool disabled);
onUidStateChanged(uid_t uid __unused,int32_t procState __unused,int64_t procStateSeq __unused)123             void onUidStateChanged(uid_t uid __unused, int32_t procState __unused,
124                                    int64_t procStateSeq __unused) {}
125 
126             void addOverrideUid(uid_t uid, bool active);
127             void removeOverrideUid(uid_t uid);
128         private:
129             bool isUidActiveLocked(uid_t uid);
130             void updateOverrideUid(uid_t uid, bool active, bool insert);
131 
132             Mutex mUidLock;
133             wp<SensorService> mService;
134             std::unordered_set<uid_t> mActiveUids;
135             std::unordered_map<uid_t, bool> mOverrideUids;
136     };
137 
138     // Sensor privacy allows a user to disable access to all sensors on the device. When
139     // enabled sensor privacy will prevent all apps, including active apps, from accessing
140     // sensors, they will not receive trigger nor on-change events, flush event behavior
141     // does not change, and recurring events are the same as the first one delivered when
142     // sensor privacy was enabled. All sensor direct connections will be stopped as well
143     // and new direct connections will not be allowed while sensor privacy is enabled.
144     // Once sensor privacy is disabled access to sensors will be restored for active
145     // apps, previously stopped direct connections will be restarted, and new direct
146     // connections will be allowed again.
147     class SensorPrivacyPolicy : public hardware::BnSensorPrivacyListener {
148         public:
SensorPrivacyPolicy(wp<SensorService> service)149             explicit SensorPrivacyPolicy(wp<SensorService> service) : mService(service) {}
150             void registerSelf();
151             void unregisterSelf();
152 
153             bool isSensorPrivacyEnabled();
154 
155             binder::Status onSensorPrivacyChanged(bool enabled);
156 
157         private:
158             wp<SensorService> mService;
159             std::atomic_bool mSensorPrivacyEnabled;
160     };
161 
162     enum Mode {
163        // The regular operating mode where any application can register/unregister/call flush on
164        // sensors.
165        NORMAL = 0,
166        // This mode is only used for testing purposes. Not all HALs support this mode. In this mode,
167        // the HAL ignores the sensor data provided by physical sensors and accepts the data that is
168        // injected from the SensorService as if it were the real sensor data. This mode is primarily
169        // used for testing various algorithms like vendor provided SensorFusion, Step Counter and
170        // Step Detector etc. Typically in this mode, there will be a client (a
171        // SensorEventConnection) which will be injecting sensor data into the HAL. Normal apps can
172        // unregister and register for any sensor that supports injection. Registering to sensors
173        // that do not support injection will give an error.  TODO(aakella) : Allow exactly one
174        // client to inject sensor data at a time.
175        DATA_INJECTION = 1,
176        // This mode is used only for testing sensors. Each sensor can be tested in isolation with
177        // the required sampling_rate and maxReportLatency parameters without having to think about
178        // the data rates requested by other applications. End user devices are always expected to be
179        // in NORMAL mode. When this mode is first activated, all active sensors from all connections
180        // are disabled. Calling flush() will return an error. In this mode, only the requests from
181        // selected apps whose package names are whitelisted are allowed (typically CTS apps).  Only
182        // these apps can register/unregister/call flush() on sensors. If SensorService switches to
183        // NORMAL mode again, all sensors that were previously registered to are activated with the
184        // corresponding paramaters if the application hasn't unregistered for sensors in the mean
185        // time.  NOTE: Non whitelisted app whose sensors were previously deactivated may still
186        // receive events if a whitelisted app requests data from the same sensor.
187        RESTRICTED = 2
188 
189       // State Transitions supported.
190       //     RESTRICTED   <---  NORMAL   ---> DATA_INJECTION
191       //                  --->           <---
192 
193       // Shell commands to switch modes in SensorService.
194       // 1) Put SensorService in RESTRICTED mode with packageName .cts. If it is already in
195       // restricted mode it is treated as a NO_OP (and packageName is NOT changed).
196       //
197       //     $ adb shell dumpsys sensorservice restrict .cts.
198       //
199       // 2) Put SensorService in DATA_INJECTION mode with packageName .xts. If it is already in
200       // data_injection mode it is treated as a NO_OP (and packageName is NOT changed).
201       //
202       //     $ adb shell dumpsys sensorservice data_injection .xts.
203       //
204       // 3) Reset sensorservice back to NORMAL mode.
205       //     $ adb shell dumpsys sensorservice enable
206     };
207 
208     static const char* WAKE_LOCK_NAME;
getServiceName()209     static char const* getServiceName() ANDROID_API { return "sensorservice"; }
210     SensorService() ANDROID_API;
211     virtual ~SensorService();
212 
213     virtual void onFirstRef();
214 
215     // Thread interface
216     virtual bool threadLoop();
217 
218     // ISensorServer interface
219     virtual Vector<Sensor> getSensorList(const String16& opPackageName);
220     virtual Vector<Sensor> getDynamicSensorList(const String16& opPackageName);
221     virtual sp<ISensorEventConnection> createSensorEventConnection(
222             const String8& packageName,
223             int requestedMode, const String16& opPackageName);
224     virtual int isDataInjectionEnabled();
225     virtual sp<ISensorEventConnection> createSensorDirectConnection(const String16& opPackageName,
226             uint32_t size, int32_t type, int32_t format, const native_handle *resource);
227     virtual int setOperationParameter(
228             int32_t handle, int32_t type, const Vector<float> &floats, const Vector<int32_t> &ints);
229     virtual status_t dump(int fd, const Vector<String16>& args);
230     String8 getSensorName(int handle) const;
231     bool isVirtualSensor(int handle) const;
232     sp<SensorInterface> getSensorInterfaceFromHandle(int handle) const;
233     bool isWakeUpSensor(int type) const;
234     void recordLastValueLocked(sensors_event_t const* buffer, size_t count);
235     static void sortEventBuffer(sensors_event_t* buffer, size_t count);
236     const Sensor& registerSensor(SensorInterface* sensor,
237                                  bool isDebug = false, bool isVirtual = false);
238     const Sensor& registerVirtualSensor(SensorInterface* sensor, bool isDebug = false);
239     const Sensor& registerDynamicSensorLocked(SensorInterface* sensor, bool isDebug = false);
240     bool unregisterDynamicSensorLocked(int handle);
241     status_t cleanupWithoutDisable(const sp<SensorEventConnection>& connection, int handle);
242     status_t cleanupWithoutDisableLocked(const sp<SensorEventConnection>& connection, int handle);
243     void cleanupAutoDisabledSensorLocked(const sp<SensorEventConnection>& connection,
244             sensors_event_t const* buffer, const int count);
245     static bool canAccessSensor(const Sensor& sensor, const char* operation,
246             const String16& opPackageName);
247     static bool hasPermissionForSensor(const Sensor& sensor);
248     static int getTargetSdkVersion(const String16& opPackageName);
249     // SensorService acquires a partial wakelock for delivering events from wake up sensors. This
250     // method checks whether all the events from these wake up sensors have been delivered to the
251     // corresponding applications, if yes the wakelock is released.
252     void checkWakeLockState();
253     void checkWakeLockStateLocked();
254     bool isWakeLockAcquired();
255     bool isWakeUpSensorEvent(const sensors_event_t& event) const;
256 
257     sp<Looper> getLooper() const;
258 
259     // Reset mWakeLockRefCounts for all SensorEventConnections to zero. This may happen if
260     // SensorService did not receive any acknowledgements from apps which have registered for
261     // wake_up sensors.
262     void resetAllWakeLockRefCounts();
263 
264     // Acquire or release wake_lock. If wake_lock is acquired, set the timeout in the looper to 5
265     // seconds and wake the looper.
266     void setWakeLockAcquiredLocked(bool acquire);
267 
268     // Send events from the event cache for this particular connection.
269     void sendEventsFromCache(const sp<SensorEventConnection>& connection);
270 
271     // Promote all weak referecences in mActiveConnections vector to strong references and add them
272     // to the output vector.
273     void populateActiveConnections( SortedVector< sp<SensorEventConnection> >* activeConnections);
274 
275     // If SensorService is operating in RESTRICTED mode, only select whitelisted packages are
276     // allowed to register for or call flush on sensors. Typically only cts test packages are
277     // allowed.
278     bool isWhiteListedPackage(const String8& packageName);
279     bool isOperationPermitted(const String16& opPackageName);
280 
281     // Reset the state of SensorService to NORMAL mode.
282     status_t resetToNormalMode();
283     status_t resetToNormalModeLocked();
284 
285     // Transforms the UUIDs for all the sensors into proper IDs.
286     void makeUuidsIntoIdsForSensorList(Vector<Sensor> &sensorList) const;
287     // Gets the appropriate ID from the given UUID.
288     int32_t getIdFromUuid(const Sensor::uuid_t &uuid) const;
289     // Either read from storage or create a new one.
290     static bool initializeHmacKey();
291 
292     // Enable SCHED_FIFO priority for thread
293     void enableSchedFifoMode();
294 
295     // Sets whether the given UID can get sensor data
296     void setSensorAccess(uid_t uid, bool hasAccess);
297 
298     // Overrides the UID state as if it is idle
299     status_t handleSetUidState(Vector<String16>& args, int err);
300     // Clears the override for the UID state
301     status_t handleResetUidState(Vector<String16>& args, int err);
302     // Gets the UID state
303     status_t handleGetUidState(Vector<String16>& args, int out, int err);
304     // Prints the shell command help
305     status_t printHelp(int out);
306 
307     // temporarily stops all active direct connections and disables all sensors
308     void disableAllSensors();
309     void disableAllSensorsLocked();
310     // restarts the previously stopped direct connections and enables all sensors
311     void enableAllSensors();
312     void enableAllSensorsLocked();
313 
314     static uint8_t sHmacGlobalKey[128];
315     static bool sHmacGlobalKeyIsValid;
316 
317     SensorServiceUtil::SensorList mSensors;
318     status_t mInitCheck;
319 
320     // Socket buffersize used to initialize BitTube. This size depends on whether batching is
321     // supported or not.
322     uint32_t mSocketBufferSize;
323     sp<Looper> mLooper;
324     sp<SensorEventAckReceiver> mAckReceiver;
325 
326     // protected by mLock
327     mutable Mutex mLock;
328     DefaultKeyedVector<int, SensorRecord*> mActiveSensors;
329     std::unordered_set<int> mActiveVirtualSensors;
330     SortedVector< wp<SensorEventConnection> > mActiveConnections;
331     bool mWakeLockAcquired;
332     sensors_event_t *mSensorEventBuffer, *mSensorEventScratch;
333     wp<const SensorEventConnection> * mMapFlushEventsToConnections;
334     std::unordered_map<int, SensorServiceUtil::RecentEventLogger*> mRecentEvent;
335     SortedVector< wp<SensorDirectConnection> > mDirectConnections;
336     Mode mCurrentOperatingMode;
337 
338     // This packagaName is set when SensorService is in RESTRICTED or DATA_INJECTION mode. Only
339     // applications with this packageName are allowed to activate/deactivate or call flush on
340     // sensors. To run CTS this is can be set to ".cts." and only CTS tests will get access to
341     // sensors.
342     String8 mWhiteListedPackage;
343 
344     int mNextSensorRegIndex;
345     Vector<SensorRegistrationInfo> mLastNSensorRegistrations;
346 
347     sp<UidPolicy> mUidPolicy;
348     sp<SensorPrivacyPolicy> mSensorPrivacyPolicy;
349 
350     static AppOpsManager sAppOpsManager;
351     static std::map<String16, int> sPackageTargetVersion;
352     static Mutex sPackageTargetVersionLock;
353 };
354 
355 } // namespace android
356 #endif // ANDROID_SENSOR_SERVICE_H
357