Add stringType and requiredPermission to sensors, effectively adding permission checking for sensors

Change-Id: If0f3dbdb5d2e9378e1fed4614baee4e750d0c850

include/android/sensor.h

@@ -281,6 +281,28 @@ float ASensor_getResolution(ASensor const* sensor);
  */
 int ASensor_getMinDelay(ASensor const* sensor);
 
+/*
+ * Returns the maximum size of batches for this sensor. Batches will often be
+ * smaller, as the hardware fifo might be used for other sensors.
+ */
+int ASensor_getFifoMaxEventCount(ASensor const* sensor);
+
+/*
+ * Returns the hardware batch fifo size reserved to this sensor.
+ */
+int ASensor_getFifoReservedEventCount(ASensor const* sensor);
+
+/*
+ * Returns this sensor's string type.
+ */
+const char* ASensor_getStringType(ASensor const* sensor);
+
+/*
+ * Returns the permission required to see or access this sensor, or the
+ * empty string if none is required.
+ */
+const char* ASensor_getRequiredPermission(ASensor const* sensor);
+
 
 #ifdef __cplusplus
 };

include/gui/Sensor.h

@@ -69,6 +69,8 @@ public:
     int32_t getVersion() const;
     int32_t getFifoReservedEventCount() const;
     int32_t getFifoMaxEventCount() const;
+    const String8& getStringType() const;
+    const String8& getRequiredPermission() const;
 
     // LightFlattenable protocol
     inline bool isFixedSize() const { return false; }
@@ -89,6 +91,10 @@ private:
     int32_t mVersion;
     int32_t mFifoReservedEventCount;
     int32_t mFifoMaxEventCount;
+    String8 mStringType;
+    String8 mRequiredPermission;
+    static void flattenString8(void*& buffer, size_t& size, const String8& string8);
+    static bool unflattenString8(void const*& buffer, size_t& size, String8& outputString8);
 };
 
 // ----------------------------------------------------------------------------

libs/gui/Sensor.cpp

@@ -48,14 +48,90 @@ Sensor::Sensor(struct sensor_t const* hwSensor, int halVersion)
     mResolution = hwSensor->resolution;
     mPower = hwSensor->power;
     mMinDelay = hwSensor->minDelay;
+
     // Set fifo event count zero for older devices which do not support batching. Fused
     // sensors also have their fifo counts set to zero.
     if (halVersion >= SENSORS_DEVICE_API_VERSION_1_1) {
         mFifoReservedEventCount = hwSensor->fifoReservedEventCount;
         mFifoMaxEventCount = hwSensor->fifoMaxEventCount;
-    } else {
+    }
-        mFifoReservedEventCount = 0;
+
-        mFifoMaxEventCount = 0;
+    // Ensure existing sensors have correct string type and required
+    // permissions.
+    switch (mType) {
+    case SENSOR_TYPE_ACCELEROMETER:
+        mStringType = SENSOR_STRING_TYPE_ACCELEROMETER;
+        break;
+    case SENSOR_TYPE_AMBIENT_TEMPERATURE:
+        mStringType = SENSOR_STRING_TYPE_AMBIENT_TEMPERATURE;
+        break;
+    case SENSOR_TYPE_GAME_ROTATION_VECTOR:
+        mStringType = SENSOR_STRING_TYPE_GAME_ROTATION_VECTOR;
+        break;
+    case SENSOR_TYPE_GEOMAGNETIC_ROTATION_VECTOR:
+        mStringType = SENSOR_STRING_TYPE_GEOMAGNETIC_ROTATION_VECTOR;
+        break;
+    case SENSOR_TYPE_GRAVITY:
+        mStringType = SENSOR_STRING_TYPE_GRAVITY;
+        break;
+    case SENSOR_TYPE_GYROSCOPE:
+        mStringType = SENSOR_STRING_TYPE_GYROSCOPE;
+        break;
+    case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+        mStringType = SENSOR_STRING_TYPE_GYROSCOPE_UNCALIBRATED;
+        break;
+    case SENSOR_TYPE_HEART_RATE:
+        mStringType = SENSOR_STRING_TYPE_HEART_RATE;
+        mRequiredPermission = SENSOR_PERMISSION_BODY_SENSORS;
+        break;
+    case SENSOR_TYPE_LIGHT:
+        mStringType = SENSOR_STRING_TYPE_LIGHT;
+        break;
+    case SENSOR_TYPE_LINEAR_ACCELERATION:
+        mStringType = SENSOR_STRING_TYPE_LINEAR_ACCELERATION;
+        break;
+    case SENSOR_TYPE_MAGNETIC_FIELD:
+        mStringType = SENSOR_STRING_TYPE_MAGNETIC_FIELD;
+        break;
+    case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+        mStringType = SENSOR_STRING_TYPE_MAGNETIC_FIELD_UNCALIBRATED;
+        break;
+    case SENSOR_TYPE_ORIENTATION:
+        mStringType = SENSOR_STRING_TYPE_ORIENTATION;
+        break;
+    case SENSOR_TYPE_PRESSURE:
+        mStringType = SENSOR_STRING_TYPE_PRESSURE;
+        break;
+    case SENSOR_TYPE_PROXIMITY:
+        mStringType = SENSOR_STRING_TYPE_PROXIMITY;
+        break;
+    case SENSOR_TYPE_RELATIVE_HUMIDITY:
+        mStringType = SENSOR_STRING_TYPE_RELATIVE_HUMIDITY;
+        break;
+    case SENSOR_TYPE_ROTATION_VECTOR:
+        mStringType = SENSOR_STRING_TYPE_ROTATION_VECTOR;
+        break;
+    case SENSOR_TYPE_SIGNIFICANT_MOTION:
+        mStringType = SENSOR_STRING_TYPE_SIGNIFICANT_MOTION;
+        break;
+    case SENSOR_TYPE_STEP_COUNTER:
+        mStringType = SENSOR_STRING_TYPE_STEP_COUNTER;
+        break;
+    case SENSOR_TYPE_STEP_DETECTOR:
+        mStringType = SENSOR_STRING_TYPE_STEP_DETECTOR;
+        break;
+    case SENSOR_TYPE_TEMPERATURE:
+        mStringType = SENSOR_STRING_TYPE_TEMPERATURE;
+        break;
+    default:
+        // Only pipe the stringType and requiredPermission for custom sensors.
+        if (halVersion >= SENSORS_DEVICE_API_VERSION_1_2 && hwSensor->stringType) {
+            mStringType = hwSensor->stringType;
+        }
+        if (halVersion >= SENSORS_DEVICE_API_VERSION_1_2 && hwSensor->requiredPermission) {
+            mRequiredPermission = hwSensor->requiredPermission;
+        }
+        break;
     }
 }
 
@@ -115,6 +191,14 @@ int32_t Sensor::getFifoMaxEventCount() const {
     return mFifoMaxEventCount;
 }
 
+const String8& Sensor::getStringType() const {
+    return mStringType;
+}
+
+const String8& Sensor::getRequiredPermission() const {
+    return mRequiredPermission;
+}
+
 size_t Sensor::getFlattenedSize() const
 {
     size_t fixedSize =
@@ -123,8 +207,10 @@ size_t Sensor::getFlattenedSize() const
             sizeof(int32_t) * 3;
 
     size_t variableSize =
-            sizeof(int32_t) + FlattenableUtils::align<4>(mName.length()) +
+            sizeof(uint32_t) + FlattenableUtils::align<4>(mName.length()) +
-            sizeof(int32_t) + FlattenableUtils::align<4>(mVendor.length());
+            sizeof(uint32_t) + FlattenableUtils::align<4>(mVendor.length()) +
+            sizeof(uint32_t) + FlattenableUtils::align<4>(mStringType.length()) +
+            sizeof(uint32_t) + FlattenableUtils::align<4>(mRequiredPermission.length());
 
     return fixedSize + variableSize;
 }
@@ -134,14 +220,8 @@ status_t Sensor::flatten(void* buffer, size_t size) const {
         return NO_MEMORY;
     }
 
-    FlattenableUtils::write(buffer, size, mName.length());
+    flattenString8(buffer, size, mName);
-    memcpy(static_cast<char*>(buffer), mName.string(), mName.length());
+    flattenString8(buffer, size, mVendor);
-    FlattenableUtils::advance(buffer, size, FlattenableUtils::align<4>(mName.length()));
-
-    FlattenableUtils::write(buffer, size, mVendor.length());
-    memcpy(static_cast<char*>(buffer), mVendor.string(), mVendor.length());
-    FlattenableUtils::advance(buffer, size, FlattenableUtils::align<4>(mVendor.length()));
-
     FlattenableUtils::write(buffer, size, mVersion);
     FlattenableUtils::write(buffer, size, mHandle);
     FlattenableUtils::write(buffer, size, mType);
@@ -152,38 +232,23 @@ status_t Sensor::flatten(void* buffer, size_t size) const {
     FlattenableUtils::write(buffer, size, mMinDelay);
     FlattenableUtils::write(buffer, size, mFifoReservedEventCount);
     FlattenableUtils::write(buffer, size, mFifoMaxEventCount);
+    flattenString8(buffer, size, mStringType);
+    flattenString8(buffer, size, mRequiredPermission);
     return NO_ERROR;
 }
 
 status_t Sensor::unflatten(void const* buffer, size_t size) {
-    size_t len;
+    if (!unflattenString8(buffer, size, mName)) {
-
-    if (size < sizeof(size_t)) {
         return NO_MEMORY;
     }
-    FlattenableUtils::read(buffer, size, len);
+    if (!unflattenString8(buffer, size, mVendor)) {
-    if (size < len) {
         return NO_MEMORY;
     }
-    mName.setTo(static_cast<char const*>(buffer), len);
-    FlattenableUtils::advance(buffer, size, FlattenableUtils::align<4>(len));
-
-
-    if (size < sizeof(size_t)) {
-        return NO_MEMORY;
-    }
-    FlattenableUtils::read(buffer, size, len);
-    if (size < len) {
-        return NO_MEMORY;
-    }
-    mVendor.setTo(static_cast<char const*>(buffer), len);
-    FlattenableUtils::advance(buffer, size, FlattenableUtils::align<4>(len));
 
     size_t fixedSize =
             sizeof(int32_t) * 3 +
             sizeof(float) * 4 +
             sizeof(int32_t) * 3;
-
     if (size < fixedSize) {
         return NO_MEMORY;
     }
@@ -198,8 +263,37 @@ status_t Sensor::unflatten(void const* buffer, size_t size) {
     FlattenableUtils::read(buffer, size, mMinDelay);
     FlattenableUtils::read(buffer, size, mFifoReservedEventCount);
     FlattenableUtils::read(buffer, size, mFifoMaxEventCount);
+
+    if (!unflattenString8(buffer, size, mStringType)) {
+        return NO_MEMORY;
+    }
+    if (!unflattenString8(buffer, size, mRequiredPermission)) {
+        return NO_MEMORY;
+    }
     return NO_ERROR;
 }
 
+void Sensor::flattenString8(void*& buffer, size_t& size,
+        const String8& string8) {
+    uint32_t len = string8.length();
+    FlattenableUtils::write(buffer, size, len);
+    memcpy(static_cast<char*>(buffer), string8.string(), len);
+    FlattenableUtils::advance(buffer, size, FlattenableUtils::align<4>(len));
+}
+
+bool Sensor::unflattenString8(void const*& buffer, size_t& size, String8& outputString8) {
+    uint32_t len;
+    if (size < sizeof(len)) {
+        return false;
+    }
+    FlattenableUtils::read(buffer, size, len);
+    if (size < len) {
+        return false;
+    }
+    outputString8.setTo(static_cast<char const*>(buffer), len);
+    FlattenableUtils::advance(buffer, size, FlattenableUtils::align<4>(len));
+    return true;
+}
+
 // ----------------------------------------------------------------------------
 }; // namespace android

services/sensorservice/SensorService.cpp

@@ -205,7 +205,7 @@ status_t SensorService::dump(int fd, const Vector<String16>& args)
     String8 result;
     if (!PermissionCache::checkCallingPermission(sDump)) {
         result.appendFormat("Permission Denial: "
-                "can't dump SurfaceFlinger from pid=%d, uid=%d\n",
+                "can't dump SensorService from pid=%d, uid=%d\n",
                 IPCThreadState::self()->getCallingPid(),
                 IPCThreadState::self()->getCallingUid());
     } else {
@@ -215,21 +215,24 @@ status_t SensorService::dump(int fd, const Vector<String16>& args)
             const Sensor& s(mSensorList[i]);
             const sensors_event_t& e(mLastEventSeen.valueFor(s.getHandle()));
             result.appendFormat(
-                    "%-48s| %-32s | 0x%08x | ",
+                    "%-48s| %-32s| %-48s| 0x%08x | \"%s\"\n\t",
                     s.getName().string(),
                     s.getVendor().string(),
-                    s.getHandle());
+                    s.getStringType().string(),
+                    s.getHandle(),
+                    s.getRequiredPermission().string());
 
             if (s.getMinDelay() > 0) {
                 result.appendFormat(
-                    "maxRate=%7.2fHz | ", 1e6f / s.getMinDelay());
+                        "maxRate=%7.2fHz | ", 1e6f / s.getMinDelay());
             } else {
                 result.append(s.getMinDelay() == 0
                         ? "on-demand         | "
                         : "one-shot          | ");
             }
             if (s.getFifoMaxEventCount() > 0) {
-                result.appendFormat("getFifoMaxEventCount=%d events | ", s.getFifoMaxEventCount());
+                result.appendFormat("FifoMax=%d events | ",
+                        s.getFifoMaxEventCount());
             } else {
                 result.append("no batching support | ");
             }
@@ -490,10 +493,23 @@ Vector<Sensor> SensorService::getSensorList()
 {
     char value[PROPERTY_VALUE_MAX];
     property_get("debug.sensors", value, "0");
-    if (atoi(value)) {
+    const Vector<Sensor>& initialSensorList = (atoi(value)) ?
-        return mUserSensorListDebug;
+            mUserSensorListDebug : mUserSensorList;
+    Vector<Sensor> accessibleSensorList;
+    for (size_t i = 0; i < initialSensorList.size(); i++) {
+        Sensor sensor = initialSensorList[i];
+        if (canAccessSensor(sensor)) {
+            accessibleSensorList.add(sensor);
+        } else {
+            String8 infoMessage;
+            infoMessage.appendFormat(
+                    "Skipped sensor %s because it requires permission %s",
+                    sensor.getName().string(),
+                    sensor.getRequiredPermission().string());
+            ALOGI(infoMessage.string());
+        }
     }
-    return mUserSensorList;
+    return accessibleSensorList;
 }
 
 sp<ISensorEventConnection> SensorService::createSensorEventConnection()
@@ -539,6 +555,10 @@ void SensorService::cleanupConnection(SensorEventConnection* c)
     BatteryService::cleanup(c->getUid());
 }
 
+Sensor SensorService::getSensorFromHandle(int handle) const {
+    return mSensorMap.valueFor(handle)->getSensor();
+}
+
 status_t SensorService::enable(const sp<SensorEventConnection>& connection,
         int handle, nsecs_t samplingPeriodNs,  nsecs_t maxBatchReportLatencyNs, int reservedFlags)
 {
@@ -549,6 +569,11 @@ status_t SensorService::enable(const sp<SensorEventConnection>& connection,
     if (sensor == NULL) {
         return BAD_VALUE;
     }
+
+    if (!verifyCanAccessSensor(sensor->getSensor(), "Tried enabling")) {
+        return BAD_VALUE;
+    }
+
     Mutex::Autolock _l(mLock);
     SensorRecord* rec = mActiveSensors.valueFor(handle);
     if (rec == 0) {
@@ -670,6 +695,10 @@ status_t SensorService::setEventRate(const sp<SensorEventConnection>& connection
     if (!sensor)
         return BAD_VALUE;
 
+    if (!verifyCanAccessSensor(sensor->getSensor(), "Tried configuring")) {
+        return BAD_VALUE;
+    }
+
     if (ns < 0)
         return BAD_VALUE;
 
@@ -683,17 +712,44 @@ status_t SensorService::setEventRate(const sp<SensorEventConnection>& connection
 
 status_t SensorService::flushSensor(const sp<SensorEventConnection>& connection,
                                     int handle) {
-  if (mInitCheck != NO_ERROR) return mInitCheck;
+    if (mInitCheck != NO_ERROR) return mInitCheck;
-  SensorInterface* sensor = mSensorMap.valueFor(handle);
+    SensorInterface* sensor = mSensorMap.valueFor(handle);
-  if (sensor == NULL) {
+    if (sensor == NULL) {
-      return BAD_VALUE;
+        return BAD_VALUE;
-  }
+    }
-  if (sensor->getSensor().getType() == SENSOR_TYPE_SIGNIFICANT_MOTION) {
+
-      ALOGE("flush called on Significant Motion sensor");
+    if (!verifyCanAccessSensor(sensor->getSensor(), "Tried flushing")) {
-      return INVALID_OPERATION;
+        return BAD_VALUE;
-  }
+    }
-  return sensor->flush(connection.get(), handle);
+
+    if (sensor->getSensor().getType() == SENSOR_TYPE_SIGNIFICANT_MOTION) {
+        ALOGE("flush called on Significant Motion sensor");
+        return INVALID_OPERATION;
+    }
+    return sensor->flush(connection.get(), handle);
 }
+
+
+bool SensorService::canAccessSensor(const Sensor& sensor) {
+    String16 permissionString(sensor.getRequiredPermission());
+    return permissionString.size() == 0 ||
+            PermissionCache::checkCallingPermission(permissionString);
+}
+
+bool SensorService::verifyCanAccessSensor(const Sensor& sensor, const char* operation) {
+    if (canAccessSensor(sensor)) {
+        return true;
+    } else {
+        String8 errorMessage;
+        errorMessage.appendFormat(
+                "%s a sensor (%s) without holding its required permission: %s",
+                operation,
+                sensor.getName().string(),
+                sensor.getRequiredPermission().string());
+        return false;
+    }
+}
+
 // ---------------------------------------------------------------------------
 
 SensorService::SensorRecord::SensorRecord(
@@ -761,6 +817,9 @@ void SensorService::SensorEventConnection::dump(String8& result) {
 
 bool SensorService::SensorEventConnection::addSensor(int32_t handle) {
     Mutex::Autolock _l(mConnectionLock);
+    if (!verifyCanAccessSensor(mService->getSensorFromHandle(handle), "Tried adding")) {
+        return false;
+    }
     if (mSensorInfo.indexOfKey(handle) < 0) {
         mSensorInfo.add(handle, FlushInfo());
         return true;

services/sensorservice/SensorService.h

@@ -131,6 +131,7 @@ class SensorService :
 
     String8 getSensorName(int handle) const;
     bool isVirtualSensor(int handle) const;
+    Sensor getSensorFromHandle(int handle) const;
     void recordLastValue(const sensors_event_t* buffer, size_t count);
     static void sortEventBuffer(sensors_event_t* buffer, size_t count);
     Sensor registerSensor(SensorInterface* sensor);
@@ -141,7 +142,8 @@ class SensorService :
             const sp<SensorEventConnection>& connection, int handle);
     void cleanupAutoDisabledSensor(const sp<SensorEventConnection>& connection,
             sensors_event_t const* buffer, const int count);
-
+    static bool canAccessSensor(const Sensor& sensor);
+    static bool verifyCanAccessSensor(const Sensor& sensor, const char* operation);
     // constants
     Vector<Sensor> mSensorList;
     Vector<Sensor> mUserSensorListDebug;