Don't record audio if UID is idle - media framework
To protect user's privacy if a UID is in an idle state we allow
recording but report silence (all zeros in the byte array) and once
the process goes in an active state we report the real mic data.
This avoids the race between the app being notified aboout its
lifecycle and the audio system being notified about the state
of a UID.
Test: Added - AudioRecordTest#testRecordNoDataForIdleUids
Passing - cts-tradefed run cts-dev -m CtsMediaTestCases
-t android.media.cts.AudioRecordTest
bug:63938985
Change-Id: I1442a9dda1553e9ea7a4a654c50555ac1ec06aa0
diff --git a/services/audiopolicy/service/AudioPolicyService.h b/services/audiopolicy/service/AudioPolicyService.h
index 833a230..9bc13c2 100644
--- a/services/audiopolicy/service/AudioPolicyService.h
+++ b/services/audiopolicy/service/AudioPolicyService.h
@@ -24,6 +24,7 @@
#include <utils/Vector.h>
#include <utils/SortedVector.h>
#include <binder/BinderService.h>
+#include <binder/IUidObserver.h>
#include <system/audio.h>
#include <system/audio_policy.h>
#include <media/IAudioPolicyService.h>
@@ -33,9 +34,13 @@
#include "AudioPolicyEffects.h"
#include "managerdefault/AudioPolicyManager.h"
+#include <unordered_map>
+#include <unordered_set>
namespace android {
+using namespace std;
+
// ----------------------------------------------------------------------------
class AudioPolicyService :
@@ -97,7 +102,10 @@
audio_port_handle_t *selectedDeviceId = NULL,
audio_port_handle_t *portId = NULL);
virtual status_t startInput(audio_io_handle_t input,
- audio_session_t session);
+ audio_session_t session,
+ audio_devices_t device,
+ uid_t uid,
+ bool *silenced);
virtual status_t stopInput(audio_io_handle_t input,
audio_session_t session);
virtual void releaseInput(audio_io_handle_t input,
@@ -235,6 +243,57 @@
status_t dumpInternals(int fd);
+ // Handles binder shell commands
+ virtual status_t shellCommand(int in, int out, int err, Vector<String16>& args);
+
+ // Sets whether the given UID records only silence
+ virtual void setRecordSilenced(uid_t uid, bool silenced);
+
+ // Overrides the UID state as if it is idle
+ status_t handleSetUidState(Vector<String16>& args, int err);
+
+ // Clears the override for the UID state
+ status_t handleResetUidState(Vector<String16>& args, int err);
+
+ // Gets the UID state
+ status_t handleGetUidState(Vector<String16>& args, int out, int err);
+
+ // Prints the shell command help
+ status_t printHelp(int out);
+
+ // If recording we need to make sure the UID is allowed to do that. If the UID is idle
+ // then it cannot record and gets buffers with zeros - silence. As soon as the UID
+ // transitions to an active state we will start reporting buffers with data. This approach
+ // transparently handles recording while the UID transitions between idle/active state
+ // avoiding to get stuck in a state receiving non-empty buffers while idle or in a state
+ // receiving empty buffers while active.
+ class UidPolicy : public BnUidObserver {
+ public:
+ explicit UidPolicy(wp<AudioPolicyService> service)
+ : mService(service) {}
+
+ void registerSelf();
+ void unregisterSelf();
+
+ bool isUidActive(uid_t uid);
+
+ void onUidGone(uid_t uid, bool disabled);
+ void onUidActive(uid_t uid);
+ void onUidIdle(uid_t uid, bool disabled);
+
+ void addOverrideUid(uid_t uid, bool active);
+ void removeOverrideUid(uid_t uid);
+
+ private:
+ bool isUidActiveLocked(uid_t uid);
+ void updateOverrideUid(uid_t uid, bool active, bool insert);
+
+ Mutex mUidLock;
+ wp<AudioPolicyService> mService;
+ std::unordered_set<uid_t> mActiveUids;
+ std::unordered_map<uid_t, bool> mOverrideUids;
+ };
+
// Thread used for tone playback and to send audio config commands to audio flinger
// For tone playback, using a separate thread is necessary to avoid deadlock with mLock because
// startTone() and stopTone() are normally called with mLock locked and requesting a tone start
@@ -306,7 +365,6 @@
const audio_config_base_t *deviceConfig,
audio_patch_handle_t patchHandle);
void insertCommand_l(AudioCommand *command, int delayMs = 0);
-
private:
class AudioCommandData;
@@ -575,6 +633,8 @@
// Manage all effects configured in audio_effects.conf
sp<AudioPolicyEffects> mAudioPolicyEffects;
audio_mode_t mPhoneState;
+
+ sp<UidPolicy> mUidPolicy;
};
} // namespace android