SurfaceFlinger: Respect the PROTECTED gralloc bit.

This change makes SurfaceFlinger treat layers for which the active
buffer has the GRALLOC_USAGE_PROTECTED bit set as if they have the
'secure' flag set.

Change-Id: Ic60b6513a63e4bb92ec6ce9fd12fd39b4ba5f674
Bug: 4081304

4 files changed, 24 insertions, 17 deletions

diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 57af001..1297363 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -57,7 +57,6 @@ Layer::Layer(SurfaceFlinger* flinger,
         mNeedsDithering(false),
         mSecure(false),
         mProtectedByApp(false),
-        mProtectedByDRM(false),
         mTextureManager(),
         mBufferManager(mTextureManager),
         mWidth(0), mHeight(0), mNeedsScaling(false), mFixedSize(false)
@@ -191,7 +190,6 @@ status_t Layer::setBuffers( uint32_t w, uint32_t h,
 
     mSecure = (flags & ISurfaceComposer::eSecure) ? true : false;
     mProtectedByApp = (flags & ISurfaceComposer::eProtectedByApp) ? true : false;
-    mProtectedByDRM = (flags & ISurfaceComposer::eProtectedByDRM) ? true : false;
     mNeedsBlending = (info.h_alpha - info.l_alpha) > 0 &&
             (flags & ISurfaceComposer::eOpaque) == 0;
 
@@ -392,6 +390,12 @@ bool Layer::needsFiltering() const
     return LayerBase::needsFiltering();
 }
 
+bool Layer::isProtected() const
+{
+    sp<GraphicBuffer> activeBuffer(mBufferManager.getActiveBuffer());
+    return (activeBuffer != 0) &&
+            (activeBuffer->getUsage() & GRALLOC_USAGE_PROTECTED);
+}
 
 status_t Layer::setBufferCount(int bufferCount)
 {
@@ -515,7 +519,7 @@ uint32_t Layer::getEffectiveUsage(uint32_t usage) const
         // request EGLImage for all buffers
         usage |= GraphicBuffer::USAGE_HW_TEXTURE;
     }
-    if (mProtectedByApp || mProtectedByDRM) {
+    if (mProtectedByApp) {
         // need a hardware-protected path to external video sink
         usage |= GraphicBuffer::USAGE_PROTECTED;
     }
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index bccc900..128f93d 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -80,8 +80,7 @@ public:
     virtual bool needsDithering() const     { return mNeedsDithering; }
     virtual bool needsFiltering() const;
     virtual bool isSecure() const           { return mSecure; }
-    virtual bool isProtectedByApp() const   { return mProtectedByApp; }
-    virtual bool isProtectedByDRM() const   { return mProtectedByDRM; }
+    virtual bool isProtected() const;
     virtual sp<Surface> createSurface() const;
     virtual status_t ditch();
     virtual void onRemoved();
@@ -222,7 +221,6 @@ private:
     // page-flip thread (currently main thread)
     bool mSecure;         // no screenshots
     bool mProtectedByApp; // application requires protected path to external sink
-    bool mProtectedByDRM; // DRM agent requires protected path to external sink
     Region mPostedDirtyRegion;
 
     // page-flip thread and transaction thread (currently main thread)
diff --git a/services/surfaceflinger/LayerBase.h b/services/surfaceflinger/LayerBase.h
index bfe92e6..7162e47 100644
--- a/services/surfaceflinger/LayerBase.h
+++ b/services/surfaceflinger/LayerBase.h
@@ -197,16 +197,10 @@ public:
     virtual bool isSecure() const       { return false; }
 
     /**
-     * isProtectedByApp - true if application says this surface is protected, that
-     * is if it requires a hardware-protected data path to an external sink.
+     * isProtected - true if the layer may contain protected content in the
+     * GRALLOC_USAGE_PROTECTED sense.
      */
-    virtual bool isProtectedByApp() const   { return false; }
-
-    /**
-     * isProtectedByDRM - true if DRM agent says this surface is protected, that
-     * is if it requires a hardware-protected data path to an external sink.
-     */
-    virtual bool isProtectedByDRM() const   { return false; }
+    virtual bool isProtected() const   { return false; }
 
     /** Called from the main thread, when the surface is removed from the
      * draw list */
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 7b19a4c..a9fa1ef 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2169,6 +2169,19 @@ status_t SurfaceFlinger::captureScreenImplLocked(DisplayID dpy,
     if (UNLIKELY(uint32_t(dpy) >= DISPLAY_COUNT))
         return BAD_VALUE;
 
+    // make sure none of the layers are protected
+    const Vector< sp<LayerBase> >& layers(mVisibleLayersSortedByZ);
+    const size_t count = layers.size();
+    for (size_t i=0 ; i<count ; ++i) {
+        const sp<LayerBase>& layer(layers[i]);
+        const uint32_t z = layer->drawingState().z;
+        if (z >= minLayerZ && z <= maxLayerZ) {
+            if (layer->isProtected()) {
+                return INVALID_OPERATION;
+            }
+        }
+    }
+
     if (!GLExtensions::getInstance().haveFramebufferObject())
         return INVALID_OPERATION;
 
@@ -2217,8 +2230,6 @@ status_t SurfaceFlinger::captureScreenImplLocked(DisplayID dpy,
         glClearColor(0,0,0,1);
         glClear(GL_COLOR_BUFFER_BIT);
 
-        const Vector< sp<LayerBase> >& layers(mVisibleLayersSortedByZ);
-        const size_t count = layers.size();
         for (size_t i=0 ; i<count ; ++i) {
             const sp<LayerBase>& layer(layers[i]);
             const uint32_t z = layer->drawingState().z;