Block access to sensors when Sensor Privacy Mode enabled

Test: manually verified sensor access based on state of sensor privacy
      mode.
Bug: 110842805

Change-Id: I4f2f2496356ff4a407e5c0cd32bc0abcf0c8b48f
diff --git a/libs/sensorprivacy/Android.bp b/libs/sensorprivacy/Android.bp
new file mode 100644
index 0000000..e0e3469
--- /dev/null
+++ b/libs/sensorprivacy/Android.bp
@@ -0,0 +1,47 @@
+// Copyright 2018 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_library_shared {
+    name: "libsensorprivacy",
+
+    aidl: {
+        export_aidl_headers: true,
+        local_include_dirs: ["aidl"],
+    },
+
+    cflags: [
+        "-Wall",
+        "-Wextra",
+        "-Werror",
+        "-Wzero-as-null-pointer-constant",
+    ],
+
+    srcs: [
+        "aidl/android/hardware/ISensorPrivacyListener.aidl",
+        "aidl/android/hardware/ISensorPrivacyManager.aidl",
+        "SensorPrivacyManager.cpp",
+    ],
+
+    shared_libs: [
+        "libbinder",
+        "libcutils",
+        "libutils",
+        "liblog",
+        "libhardware",
+    ],
+
+    export_include_dirs: ["include"],
+
+    export_shared_lib_headers: ["libbinder"],
+}
diff --git a/libs/sensorprivacy/SensorPrivacyManager.cpp b/libs/sensorprivacy/SensorPrivacyManager.cpp
new file mode 100644
index 0000000..1da79a0
--- /dev/null
+++ b/libs/sensorprivacy/SensorPrivacyManager.cpp
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <mutex>
+#include <unistd.h>
+
+#include <binder/Binder.h>
+#include <binder/IServiceManager.h>
+#include <sensorprivacy/SensorPrivacyManager.h>
+
+#include <utils/SystemClock.h>
+
+namespace android {
+
+SensorPrivacyManager::SensorPrivacyManager()
+{
+}
+
+sp<hardware::ISensorPrivacyManager> SensorPrivacyManager::getService()
+{
+    std::lock_guard<Mutex> scoped_lock(mLock);
+    int64_t startTime = 0;
+    sp<hardware::ISensorPrivacyManager> service = mService;
+    while (service == nullptr || !IInterface::asBinder(service)->isBinderAlive()) {
+        sp<IBinder> binder = defaultServiceManager()->checkService(String16("sensor_privacy"));
+        if (binder == nullptr) {
+            // Wait for the sensor privacy service to come back...
+            if (startTime == 0) {
+                startTime = uptimeMillis();
+                ALOGI("Waiting for sensor privacy service");
+            } else if ((uptimeMillis() - startTime) > 1000000) {
+                ALOGW("Waiting too long for sensor privacy service, giving up");
+                service = nullptr;
+                break;
+            }
+            usleep(25000);
+        } else {
+            service = interface_cast<hardware::ISensorPrivacyManager>(binder);
+            mService = service;
+        }
+    }
+    return service;
+}
+
+void SensorPrivacyManager::addSensorPrivacyListener(
+        const sp<hardware::ISensorPrivacyListener>& listener)
+{
+    sp<hardware::ISensorPrivacyManager> service = getService();
+    if (service != nullptr) {
+        service->addSensorPrivacyListener(listener);
+    }
+}
+
+void SensorPrivacyManager::removeSensorPrivacyListener(
+        const sp<hardware::ISensorPrivacyListener>& listener)
+{
+    sp<hardware::ISensorPrivacyManager> service = getService();
+    if (service != nullptr) {
+        service->removeSensorPrivacyListener(listener);
+    }
+}
+
+bool SensorPrivacyManager::isSensorPrivacyEnabled()
+{
+    sp<hardware::ISensorPrivacyManager> service = getService();
+    if (service != nullptr) {
+        bool result;
+        service->isSensorPrivacyEnabled(&result);
+        return result;
+    }
+    // if the SensorPrivacyManager is not available then assume sensor privacy is disabled
+    return false;
+}
+
+}; // namespace android
diff --git a/libs/sensorprivacy/aidl/android/hardware/ISensorPrivacyListener.aidl b/libs/sensorprivacy/aidl/android/hardware/ISensorPrivacyListener.aidl
new file mode 100644
index 0000000..58177d8
--- /dev/null
+++ b/libs/sensorprivacy/aidl/android/hardware/ISensorPrivacyListener.aidl
@@ -0,0 +1,24 @@
+/**
+ * Copyright (c) 2018, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.hardware;
+
+/**
+ * @hide
+ */
+oneway interface ISensorPrivacyListener {
+    void onSensorPrivacyChanged(boolean enabled);
+}
diff --git a/libs/sensorprivacy/aidl/android/hardware/ISensorPrivacyManager.aidl b/libs/sensorprivacy/aidl/android/hardware/ISensorPrivacyManager.aidl
new file mode 100644
index 0000000..4c2d5db
--- /dev/null
+++ b/libs/sensorprivacy/aidl/android/hardware/ISensorPrivacyManager.aidl
@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2018, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.hardware;
+
+import android.hardware.ISensorPrivacyListener;
+
+/** @hide */
+interface ISensorPrivacyManager {
+    void addSensorPrivacyListener(in ISensorPrivacyListener listener);
+
+    void removeSensorPrivacyListener(in ISensorPrivacyListener listener);
+
+    boolean isSensorPrivacyEnabled();
+
+    void setSensorPrivacy(boolean enable);
+}
diff --git a/libs/sensorprivacy/include/sensorprivacy/SensorPrivacyManager.h b/libs/sensorprivacy/include/sensorprivacy/SensorPrivacyManager.h
new file mode 100644
index 0000000..8826595
--- /dev/null
+++ b/libs/sensorprivacy/include/sensorprivacy/SensorPrivacyManager.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SENSOR_PRIVACY_MANAGER_H
+#define ANDROID_SENSOR_PRIVACY_MANAGER_H
+
+#include "android/hardware/ISensorPrivacyListener.h"
+#include "android/hardware/ISensorPrivacyManager.h"
+
+#include <utils/threads.h>
+
+// ---------------------------------------------------------------------------
+namespace android {
+
+class SensorPrivacyManager
+{
+public:
+    SensorPrivacyManager();
+
+    void addSensorPrivacyListener(const sp<hardware::ISensorPrivacyListener>& listener);
+    void removeSensorPrivacyListener(const sp<hardware::ISensorPrivacyListener>& listener);
+    bool isSensorPrivacyEnabled();
+
+private:
+    Mutex mLock;
+    sp<hardware::ISensorPrivacyManager> mService;
+    sp<hardware::ISensorPrivacyManager> getService();
+};
+
+
+}; // namespace android
+// ---------------------------------------------------------------------------
+
+#endif // ANDROID_SENSOR_PRIVACY_MANAGER_H