cameraserver: Add support for hiding secure cameras.

Bug: 123046494

Test: Sanity -> GCA
Test: Hardcode all cameras hidden, AImageReaderVendorTest passes, GCA
      cannot find cameras.

Change-Id: I7780751101c660e47d84627ec191f43d268f1aa9
Signed-off-by: Jayant Chowdhary <jchowdhary@google.com>
diff --git a/services/camera/libcameraservice/CameraService.cpp b/services/camera/libcameraservice/CameraService.cpp
index c3113bf..ee8d7e1 100644
--- a/services/camera/libcameraservice/CameraService.cpp
+++ b/services/camera/libcameraservice/CameraService.cpp
@@ -49,6 +49,7 @@
 #include <hardware/hardware.h>
 #include "hidl/HidlCameraService.h"
 #include <hidl/HidlTransportSupport.h>
+#include <hwbinder/IPCThreadState.h>
 #include <memunreachable/memunreachable.h>
 #include <media/AudioSystem.h>
 #include <media/IMediaHTTPService.h>
@@ -226,7 +227,7 @@
     Mutex::Autolock lock(mStatusListenerLock);
 
     for (auto& i : mListenerList) {
-        i->onTorchStatusChanged(mapToInterface(status), String16{cameraId});
+        i.second->onTorchStatusChanged(mapToInterface(status), String16{cameraId});
     }
 }
 
@@ -1287,6 +1288,18 @@
     return ret;
 }
 
+bool CameraService::shouldRejectHiddenCameraConnection(const String8 & cameraId) {
+    // If the thread serving this call is not a hwbinder thread and the caller
+    // isn't the cameraserver itself, and the camera id being requested is to be
+    // publically hidden, we should reject the connection.
+    if (!hardware::IPCThreadState::self()->isServingCall() &&
+            CameraThreadState::getCallingPid() != getpid() &&
+            mCameraProviderManager->isPublicallyHiddenSecureCamera(cameraId.c_str())) {
+        return true;
+    }
+    return false;
+}
+
 Status CameraService::connectDevice(
         const sp<hardware::camera2::ICameraDeviceCallbacks>& cameraCb,
         const String16& cameraId,
@@ -1299,6 +1312,7 @@
     Status ret = Status::ok();
     String8 id = String8(cameraId);
     sp<CameraDeviceClient> client = nullptr;
+
     ret = connectHelper<hardware::camera2::ICameraDeviceCallbacks,CameraDeviceClient>(cameraCb, id,
             /*api1CameraId*/-1,
             CAMERA_HAL_API_VERSION_UNSPECIFIED, clientPackageName,
@@ -1330,6 +1344,14 @@
             (halVersion == -1) ? "default" : std::to_string(halVersion).c_str(),
             static_cast<int>(effectiveApiLevel));
 
+    if (shouldRejectHiddenCameraConnection(cameraId)) {
+        ALOGW("Attempting to connect to system-only camera id %s, connection rejected",
+              cameraId.c_str());
+        return STATUS_ERROR_FMT(ERROR_DISCONNECTED,
+                                "No camera device with ID \"%s\" currently available",
+                                cameraId.string());
+
+    }
     sp<CLIENT> client = nullptr;
     {
         // Acquire mServiceLock and prevent other clients from connecting
@@ -1635,6 +1657,14 @@
 Status CameraService::addListener(const sp<ICameraServiceListener>& listener,
         /*out*/
         std::vector<hardware::CameraStatus> *cameraStatuses) {
+    return addListenerHelper(listener, cameraStatuses);
+}
+
+Status CameraService::addListenerHelper(const sp<ICameraServiceListener>& listener,
+        /*out*/
+        std::vector<hardware::CameraStatus> *cameraStatuses,
+        bool isVendorListener) {
+
     ATRACE_CALL();
 
     ALOGV("%s: Add listener %p", __FUNCTION__, listener.get());
@@ -1649,20 +1679,26 @@
     {
         Mutex::Autolock lock(mStatusListenerLock);
         for (auto& it : mListenerList) {
-            if (IInterface::asBinder(it) == IInterface::asBinder(listener)) {
+            if (IInterface::asBinder(it.second) == IInterface::asBinder(listener)) {
                 ALOGW("%s: Tried to add listener %p which was already subscribed",
                       __FUNCTION__, listener.get());
                 return STATUS_ERROR(ERROR_ALREADY_EXISTS, "Listener already registered");
             }
         }
 
-        mListenerList.push_back(listener);
+        mListenerList.emplace_back(isVendorListener, listener);
     }
 
     /* Collect current devices and status */
     {
         Mutex::Autolock lock(mCameraStatesLock);
         for (auto& i : mCameraStates) {
+            if (!isVendorListener &&
+                mCameraProviderManager->isPublicallyHiddenSecureCamera(i.first.c_str())) {
+                ALOGV("Cannot add public listener for hidden system-only %s for pid %d",
+                      i.first.c_str(), CameraThreadState::getCallingPid());
+                continue;
+            }
             cameraStatuses->emplace_back(i.first, mapToInterface(i.second->getStatus()));
         }
     }
@@ -1697,7 +1733,7 @@
     {
         Mutex::Autolock lock(mStatusListenerLock);
         for (auto it = mListenerList.begin(); it != mListenerList.end(); it++) {
-            if (IInterface::asBinder(*it) == IInterface::asBinder(listener)) {
+            if (IInterface::asBinder(it->second) == IInterface::asBinder(listener)) {
                 mListenerList.erase(it);
                 return Status::ok();
             }
@@ -3033,7 +3069,13 @@
             Mutex::Autolock lock(mStatusListenerLock);
 
             for (auto& listener : mListenerList) {
-                listener->onStatusChanged(mapToInterface(status), String16(cameraId));
+                if (!listener.first &&
+                    mCameraProviderManager->isPublicallyHiddenSecureCamera(cameraId.c_str())) {
+                    ALOGV("Skipping camera discovery callback for system-only camera %s",
+                          cameraId.c_str());
+                    continue;
+                }
+                listener.second->onStatusChanged(mapToInterface(status), String16(cameraId));
             }
         });
 }
diff --git a/services/camera/libcameraservice/CameraService.h b/services/camera/libcameraservice/CameraService.h
index a296198..3af52fa 100644
--- a/services/camera/libcameraservice/CameraService.h
+++ b/services/camera/libcameraservice/CameraService.h
@@ -173,6 +173,10 @@
 
     virtual status_t    shellCommand(int in, int out, int err, const Vector<String16>& args);
 
+    binder::Status      addListenerHelper(const sp<hardware::ICameraServiceListener>& listener,
+            /*out*/
+            std::vector<hardware::CameraStatus>* cameraStatuses, bool isVendor = false);
+
     /////////////////////////////////////////////////////////////////////
     // Client functionality
 
@@ -615,6 +619,10 @@
         sp<BasicClient>* client,
         std::shared_ptr<resource_policy::ClientDescriptor<String8, sp<BasicClient>>>* partial);
 
+    // Should an operation attempt on a cameraId be rejected, if the camera id is
+    // advertised as a publically hidden secure camera, by the camera HAL ?
+    bool shouldRejectHiddenCameraConnection(const String8 & cameraId);
+
     // Single implementation shared between the various connect calls
     template<class CALLBACK, class CLIENT>
     binder::Status connectHelper(const sp<CALLBACK>& cameraCb, const String8& cameraId,
@@ -781,7 +789,8 @@
     sp<CameraProviderManager> mCameraProviderManager;
 
     // Guarded by mStatusListenerMutex
-    std::vector<sp<hardware::ICameraServiceListener>> mListenerList;
+    std::vector<std::pair<bool, sp<hardware::ICameraServiceListener>>> mListenerList;
+
     Mutex       mStatusListenerLock;
 
     /**
diff --git a/services/camera/libcameraservice/common/CameraProviderManager.cpp b/services/camera/libcameraservice/common/CameraProviderManager.cpp
index 3059b07..ad4fc5f 100644
--- a/services/camera/libcameraservice/common/CameraProviderManager.cpp
+++ b/services/camera/libcameraservice/common/CameraProviderManager.cpp
@@ -504,6 +504,17 @@
     }
 }
 
+bool CameraProviderManager::ProviderInfo::DeviceInfo3::isPublicallyHiddenSecureCamera() {
+    camera_metadata_entry_t entryCap;
+    entryCap = mCameraCharacteristics.find(ANDROID_REQUEST_AVAILABLE_CAPABILITIES);
+    if (entryCap.count != 1) {
+        // Do NOT hide this camera device if the capabilities specify anything more
+        // than ANDROID_REQUEST_AVAILABLE_CAPABILITIES_SECURE_IMAGE_DATA.
+        return false;
+    }
+    return entryCap.data.u8[0] == ANDROID_REQUEST_AVAILABLE_CAPABILITIES_SECURE_IMAGE_DATA;
+}
+
 void CameraProviderManager::ProviderInfo::DeviceInfo3::getSupportedSizes(
         const CameraMetadata& ch, uint32_t tag, android_pixel_format_t format,
         std::vector<std::tuple<size_t, size_t>> *sizes/*out*/) {
@@ -882,6 +893,16 @@
     return deviceInfo->mIsLogicalCamera;
 }
 
+bool CameraProviderManager::isPublicallyHiddenSecureCamera(const std::string& id) {
+    std::lock_guard<std::mutex> lock(mInterfaceMutex);
+
+    auto deviceInfo = findDeviceInfoLocked(id);
+    if (deviceInfo == nullptr) {
+        return false;
+    }
+    return deviceInfo->mIsPublicallyHiddenSecureCamera;
+}
+
 bool CameraProviderManager::isHiddenPhysicalCamera(const std::string& cameraId) {
     for (auto& provider : mProviders) {
         for (auto& deviceInfo : provider->mDevices) {
@@ -1709,6 +1730,9 @@
                 __FUNCTION__, id.c_str(), CameraProviderManager::statusToString(status), status);
         return;
     }
+
+    mIsPublicallyHiddenSecureCamera = isPublicallyHiddenSecureCamera();
+
     status_t res = fixupMonochromeTags();
     if (OK != res) {
         ALOGE("%s: Unable to fix up monochrome tags based for older HAL version: %s (%d)",
@@ -1731,6 +1755,7 @@
     }
 
     queryPhysicalCameraIds();
+
     // Get physical camera characteristics if applicable
     auto castResult = device::V3_5::ICameraDevice::castFrom(interface);
     if (!castResult.isOk()) {
diff --git a/services/camera/libcameraservice/common/CameraProviderManager.h b/services/camera/libcameraservice/common/CameraProviderManager.h
index fbd7d2e..18869f5 100644
--- a/services/camera/libcameraservice/common/CameraProviderManager.h
+++ b/services/camera/libcameraservice/common/CameraProviderManager.h
@@ -264,6 +264,7 @@
      */
     bool isLogicalCamera(const std::string& id, std::vector<std::string>* physicalCameraIds);
 
+    bool isPublicallyHiddenSecureCamera(const std::string& id);
     bool isHiddenPhysicalCamera(const std::string& cameraId);
 
     static const float kDepthARTolerance;
@@ -354,6 +355,7 @@
             std::vector<std::string> mPhysicalIds;
             hardware::CameraInfo mInfo;
             sp<IBase> mSavedInterface;
+            bool mIsPublicallyHiddenSecureCamera = false;
 
             const hardware::camera::common::V1_0::CameraResourceCost mResourceCost;
 
@@ -471,6 +473,7 @@
             CameraMetadata mCameraCharacteristics;
             std::unordered_map<std::string, CameraMetadata> mPhysicalCameraCharacteristics;
             void queryPhysicalCameraIds();
+            bool isPublicallyHiddenSecureCamera();
             status_t fixupMonochromeTags();
             status_t addDynamicDepthTags();
             static void getSupportedSizes(const CameraMetadata& ch, uint32_t tag,
diff --git a/services/camera/libcameraservice/hidl/HidlCameraService.cpp b/services/camera/libcameraservice/hidl/HidlCameraService.cpp
index 48f1d37..74cfe42 100644
--- a/services/camera/libcameraservice/hidl/HidlCameraService.cpp
+++ b/services/camera/libcameraservice/hidl/HidlCameraService.cpp
@@ -182,7 +182,8 @@
         }
     }
     std::vector<hardware::CameraStatus> cameraStatusAndIds{};
-    binder::Status serviceRet = mAidlICameraService->addListener(csListener, &cameraStatusAndIds);
+    binder::Status serviceRet =
+        mAidlICameraService->addListenerHelper(csListener, &cameraStatusAndIds, true);
     HStatus status = HStatus::NO_ERROR;
     if (!serviceRet.isOk()) {
       ALOGE("%s: Unable to add camera device status listener", __FUNCTION__);