Bug 1497034 - FeaturePolicy: autoplay, r=cpearce

dom/media/AutoplayPolicy.cpp

@@ -11,6 +11,7 @@
 #include "mozilla/Preferences.h"
 #include "mozilla/dom/AudioContext.h"
 #include "mozilla/AutoplayPermissionManager.h"
+#include "mozilla/dom/FeaturePolicyUtils.h"
 #include "mozilla/dom/HTMLMediaElement.h"
 #include "mozilla/dom/HTMLMediaElementBinding.h"
 #include "nsGlobalWindowInner.h"
@@ -79,6 +80,16 @@ IsWindowAllowedToPlay(nsPIDOMWindowInner* aWindow)
     return false;
   }
 
+  // Here we are checking whether the current document is blocked via
+  // feature-policy, and further down we walk up the doc tree to the top level
+  // content document and check permissions etc on the top level content
+  // document. FeaturePolicy propagates the permission to any sub-documents if
+  // they don't have special directives.
+  if (!FeaturePolicyUtils::IsFeatureAllowed(aWindow->GetExtantDoc(),
+                                            NS_LITERAL_STRING("autoplay"))) {
+    return false;
+  }
+
   nsIDocument* approver = ApproverDocOf(*aWindow->GetExtantDoc());
   if (nsContentUtils::IsExactSitePermAllow(approver->NodePrincipal(),
                                            "autoplay-media")) {

dom/security/featurepolicy/FeaturePolicyUtils.cpp

@@ -25,7 +25,6 @@ struct FeatureMap {
  * DOM Security peer!
  */
 static FeatureMap sSupportedFeatures[] = {
-  // TODO: not supported yet!!!
   { "autoplay", FeatureMap::eAll },
   // TODO: not supported yet!!!
   { "camera", FeatureMap::eAll  },

testing/web-platform/meta/html/semantics/embedded-content/media-elements/__dir__.ini

@@ -1 +1,2 @@
+prefs: [dom.security.featurePolicy.enabled:true]
 lsan-allowed: []

testing/web-platform/meta/html/semantics/embedded-content/media-elements/autoplay-allowed-by-feature-policy-attribute-redirect-on-load.https.sub.html.ini

@@ -1,7 +1,7 @@
 [autoplay-allowed-by-feature-policy-attribute-redirect-on-load.https.sub.html]
   expected: TIMEOUT
   [Feature-Policy allow="autoplay" disallows cross-origin navigation in an iframe.]
-    expected: TIMEOUT
+    expected: FAIL
 
   [Feature-Policy allow="autoplay" allows same-origin navigation in an iframe.]
     expected: TIMEOUT

testing/web-platform/meta/html/semantics/embedded-content/media-elements/autoplay-allowed-by-feature-policy-attribute.https.sub.html.ini

@@ -1,8 +1,5 @@
 [autoplay-allowed-by-feature-policy-attribute.https.sub.html]
   expected: TIMEOUT
-  [Feature policy "autoplay" can be enabled in cross-origin iframe using allow="autoplay" attribute]
-    expected: TIMEOUT
-
   [Feature policy "autoplay" can be enabled in same-origin iframe using allow="autoplay" attribute]
     expected: TIMEOUT