Fix android.permission.CAPTURE_AUDIO_OUTPUT permission check

Make sure we use the correct PID and UID when checking
android.permission.CAPTURE_AUDIO_OUTPUT permission from audio
policy service.

Bug: 28772898
Change-Id: I8f0c45bf7a5728b4364a451eefb6c025892ae9a5
diff --git a/include/media/AudioSystem.h b/include/media/AudioSystem.h
index 585ef59..2e6646a 100644
--- a/include/media/AudioSystem.h
+++ b/include/media/AudioSystem.h
@@ -238,6 +238,7 @@
     static status_t getInputForAttr(const audio_attributes_t *attr,
                                     audio_io_handle_t *input,
                                     audio_session_t session,
+                                    pid_t pid,
                                     uid_t uid,
                                     uint32_t samplingRate,
                                     audio_format_t format,
diff --git a/include/media/IAudioPolicyService.h b/include/media/IAudioPolicyService.h
index 80437dc..0e9e3bc 100644
--- a/include/media/IAudioPolicyService.h
+++ b/include/media/IAudioPolicyService.h
@@ -81,6 +81,7 @@
     virtual status_t  getInputForAttr(const audio_attributes_t *attr,
                               audio_io_handle_t *input,
                               audio_session_t session,
+                              pid_t pid,
                               uid_t uid,
                               uint32_t samplingRate,
                               audio_format_t format,
diff --git a/include/media/stagefright/AudioSource.h b/include/media/stagefright/AudioSource.h
index 3074910..8fc410d 100644
--- a/include/media/stagefright/AudioSource.h
+++ b/include/media/stagefright/AudioSource.h
@@ -38,7 +38,9 @@
             const String16 &opPackageName,
             uint32_t sampleRate,
             uint32_t channels,
-            uint32_t outSampleRate = 0);
+            uint32_t outSampleRate = 0,
+            uid_t uid = -1,
+            pid_t pid = -1);
 
     status_t initCheck() const;
 
diff --git a/media/libmedia/AudioRecord.cpp b/media/libmedia/AudioRecord.cpp
index 343bf1a..d9bb856 100644
--- a/media/libmedia/AudioRecord.cpp
+++ b/media/libmedia/AudioRecord.cpp
@@ -533,7 +533,8 @@
     status = AudioSystem::getInputForAttr(&mAttributes, &input,
                                         mSessionId,
                                         // FIXME compare to AudioTrack
-                                        IPCThreadState::self()->getCallingUid(),
+                                        mClientPid,
+                                        mClientUid,
                                         mSampleRate, mFormat, mChannelMask,
                                         mFlags, mSelectedDeviceId);
 
diff --git a/media/libmedia/AudioSystem.cpp b/media/libmedia/AudioSystem.cpp
index bbdf65e..808b3ab 100644
--- a/media/libmedia/AudioSystem.cpp
+++ b/media/libmedia/AudioSystem.cpp
@@ -836,6 +836,7 @@
 status_t AudioSystem::getInputForAttr(const audio_attributes_t *attr,
                                 audio_io_handle_t *input,
                                 audio_session_t session,
+                                pid_t pid,
                                 uid_t uid,
                                 uint32_t samplingRate,
                                 audio_format_t format,
@@ -846,7 +847,8 @@
     const sp<IAudioPolicyService>& aps = AudioSystem::get_audio_policy_service();
     if (aps == 0) return NO_INIT;
     return aps->getInputForAttr(
-            attr, input, session, uid, samplingRate, format, channelMask, flags, selectedDeviceId);
+            attr, input, session, pid, uid,
+            samplingRate, format, channelMask, flags, selectedDeviceId);
 }
 
 status_t AudioSystem::startInput(audio_io_handle_t input,
diff --git a/media/libmedia/IAudioPolicyService.cpp b/media/libmedia/IAudioPolicyService.cpp
index 4ea67da..6405d6d 100644
--- a/media/libmedia/IAudioPolicyService.cpp
+++ b/media/libmedia/IAudioPolicyService.cpp
@@ -280,6 +280,7 @@
     virtual status_t getInputForAttr(const audio_attributes_t *attr,
                                      audio_io_handle_t *input,
                                      audio_session_t session,
+                                     pid_t pid,
                                      uid_t uid,
                                      uint32_t samplingRate,
                                      audio_format_t format,
@@ -299,6 +300,7 @@
         }
         data.write(attr, sizeof(audio_attributes_t));
         data.writeInt32(session);
+        data.writeInt32(pid);
         data.writeInt32(uid);
         data.writeInt32(samplingRate);
         data.writeInt32(static_cast <uint32_t>(format));
@@ -959,6 +961,7 @@
             audio_attributes_t attr;
             data.read(&attr, sizeof(audio_attributes_t));
             audio_session_t session = (audio_session_t)data.readInt32();
+            pid_t pid = (pid_t)data.readInt32();
             uid_t uid = (uid_t)data.readInt32();
             uint32_t samplingRate = data.readInt32();
             audio_format_t format = (audio_format_t) data.readInt32();
@@ -966,7 +969,7 @@
             audio_input_flags_t flags = (audio_input_flags_t) data.readInt32();
             audio_port_handle_t selectedDeviceId = (audio_port_handle_t) data.readInt32();
             audio_io_handle_t input = AUDIO_IO_HANDLE_NONE;
-            status_t status = getInputForAttr(&attr, &input, session, uid,
+            status_t status = getInputForAttr(&attr, &input, session, pid, uid,
                                               samplingRate, format, channelMask,
                                               flags, selectedDeviceId);
             reply->writeInt32(status);
diff --git a/media/libmediaplayerservice/StagefrightRecorder.cpp b/media/libmediaplayerservice/StagefrightRecorder.cpp
index 6114af8..97ba76b 100644
--- a/media/libmediaplayerservice/StagefrightRecorder.cpp
+++ b/media/libmediaplayerservice/StagefrightRecorder.cpp
@@ -934,7 +934,9 @@
                 mOpPackageName,
                 sourceSampleRate,
                 mAudioChannels,
-                mSampleRate);
+                mSampleRate,
+                mClientUid,
+                mClientPid);
 
     status_t err = audioSource->initCheck();
 
diff --git a/media/libstagefright/AudioSource.cpp b/media/libstagefright/AudioSource.cpp
index c8b61ca..790c6da 100644
--- a/media/libstagefright/AudioSource.cpp
+++ b/media/libstagefright/AudioSource.cpp
@@ -51,7 +51,8 @@
 
 AudioSource::AudioSource(
         audio_source_t inputSource, const String16 &opPackageName,
-        uint32_t sampleRate, uint32_t channelCount, uint32_t outSampleRate)
+        uint32_t sampleRate, uint32_t channelCount, uint32_t outSampleRate,
+        uid_t uid, pid_t pid)
     : mStarted(false),
       mSampleRate(sampleRate),
       mOutSampleRate(outSampleRate > 0 ? outSampleRate : sampleRate),
@@ -91,7 +92,12 @@
                     (size_t) (bufCount * frameCount),
                     AudioRecordCallbackFunction,
                     this,
-                    frameCount /*notificationFrames*/);
+                    frameCount /*notificationFrames*/,
+                    AUDIO_SESSION_ALLOCATE,
+                    AudioRecord::TRANSFER_DEFAULT,
+                    AUDIO_INPUT_FLAG_NONE,
+                    uid,
+                    pid);
         mInitCheck = mRecord->initCheck();
         if (mInitCheck != OK) {
             mRecord.clear();
diff --git a/services/audioflinger/ServiceUtilities.cpp b/services/audioflinger/ServiceUtilities.cpp
index afc2440..3c73543 100644
--- a/services/audioflinger/ServiceUtilities.cpp
+++ b/services/audioflinger/ServiceUtilities.cpp
@@ -105,11 +105,10 @@
     return true;
 }
 
-bool captureAudioOutputAllowed() {
+bool captureAudioOutputAllowed(pid_t pid, uid_t uid) {
     if (getpid_cached == IPCThreadState::self()->getCallingPid()) return true;
     static const String16 sCaptureAudioOutput("android.permission.CAPTURE_AUDIO_OUTPUT");
-    // IMPORTANT: Use PermissionCache - not a runtime permission and may not change.
-    bool ok = PermissionCache::checkCallingPermission(sCaptureAudioOutput);
+    bool ok = checkPermission(sCaptureAudioOutput, pid, uid);
     if (!ok) ALOGE("Request requires android.permission.CAPTURE_AUDIO_OUTPUT");
     return ok;
 }
diff --git a/services/audioflinger/ServiceUtilities.h b/services/audioflinger/ServiceUtilities.h
index 1e79553..8b1bc00 100644
--- a/services/audioflinger/ServiceUtilities.h
+++ b/services/audioflinger/ServiceUtilities.h
@@ -21,7 +21,7 @@
 extern pid_t getpid_cached;
 bool isTrustedCallingUid(uid_t uid);
 bool recordingAllowed(const String16& opPackageName, pid_t pid, uid_t uid);
-bool captureAudioOutputAllowed();
+bool captureAudioOutputAllowed(pid_t pid, uid_t uid);
 bool captureHotwordAllowed();
 bool settingsAllowed();
 bool modifyAudioRoutingAllowed();
diff --git a/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp b/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp
index 09a931f..151d066 100644
--- a/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp
+++ b/services/audiopolicy/service/AudioPolicyClientImplLegacy.cpp
@@ -190,7 +190,8 @@
     }
 
     if (((*pDevices & AUDIO_DEVICE_IN_REMOTE_SUBMIX) == AUDIO_DEVICE_IN_REMOTE_SUBMIX)
-            && !captureAudioOutputAllowed()) {
+            && !captureAudioOutputAllowed(IPCThreadState::self()->getCallingPid(),
+                                          IPCThreadState::self()->getCallingUid())) {
         ALOGE("open_input() permission denied: capture not allowed");
         return AUDIO_IO_HANDLE_NONE;
     }
diff --git a/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp b/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp
index 92a1285..02603b8 100644
--- a/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp
+++ b/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp
@@ -260,6 +260,7 @@
 status_t AudioPolicyService::getInputForAttr(const audio_attributes_t *attr,
                                              audio_io_handle_t *input,
                                              audio_session_t session,
+                                             pid_t pid,
                                              uid_t uid,
                                              uint32_t samplingRate,
                                              audio_format_t format,
@@ -282,11 +283,22 @@
     sp<AudioPolicyEffects>audioPolicyEffects;
     status_t status;
     AudioPolicyInterface::input_type_t inputType;
+
+    bool updatePid = (pid == -1);
     const uid_t callingUid = IPCThreadState::self()->getCallingUid();
-    if (!isTrustedCallingUid(callingUid) || uid == (uid_t)-1) {
-        ALOGW_IF(uid != (uid_t)-1 && uid != callingUid,
+    if (!isTrustedCallingUid(callingUid)) {
+        ALOGW_IF(uid != -1 && uid != (int)callingUid,
                 "%s uid %d tried to pass itself off as %d", __FUNCTION__, callingUid, uid);
         uid = callingUid;
+        updatePid = true;
+    }
+
+    if (updatePid) {
+        const pid_t callingPid = IPCThreadState::self()->getCallingPid();
+        ALOGW_IF(pid != -1 && pid != callingPid,
+                 "%s uid %d pid %d tried to pass itself off as pid %d",
+                 __func__, callingUid, callingPid, pid);
+        pid = callingPid;
     }
 
     {
@@ -306,7 +318,7 @@
             case AudioPolicyInterface::API_INPUT_TELEPHONY_RX:
                 // FIXME: use the same permission as for remote submix for now.
             case AudioPolicyInterface::API_INPUT_MIX_CAPTURE:
-                if (!captureAudioOutputAllowed()) {
+                if (!captureAudioOutputAllowed(pid, uid)) {
                     ALOGE("getInputForAttr() permission denied: capture not allowed");
                     status = PERMISSION_DENIED;
                 }
diff --git a/services/audiopolicy/service/AudioPolicyInterfaceImplLegacy.cpp b/services/audiopolicy/service/AudioPolicyInterfaceImplLegacy.cpp
index c830454..7c9315d 100644
--- a/services/audiopolicy/service/AudioPolicyInterfaceImplLegacy.cpp
+++ b/services/audiopolicy/service/AudioPolicyInterfaceImplLegacy.cpp
@@ -234,6 +234,7 @@
 status_t AudioPolicyService::getInputForAttr(const audio_attributes_t *attr,
                                              audio_io_handle_t *input,
                                              audio_session_t session,
+                                             pid_t pid __unused,
                                              uid_t uid __unused,
                                              uint32_t samplingRate,
                                              audio_format_t format,
diff --git a/services/audiopolicy/service/AudioPolicyService.h b/services/audiopolicy/service/AudioPolicyService.h
index 2710ac7..0b2cb35 100644
--- a/services/audiopolicy/service/AudioPolicyService.h
+++ b/services/audiopolicy/service/AudioPolicyService.h
@@ -99,6 +99,7 @@
     virtual status_t getInputForAttr(const audio_attributes_t *attr,
                                      audio_io_handle_t *input,
                                      audio_session_t session,
+                                     pid_t pid,
                                      uid_t uid,
                                      uint32_t samplingRate,
                                      audio_format_t format,