Bug 776649, part 3: Add an API for checking whether apps loaded in PBrowserParent/PContentParent have a given permission. r=jlebar sr=bz

dom/ipc/AppProcessPermissions.cpp

@@ -0,0 +1,54 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "AppProcessPermissions.h"
+#include "ContentParent.h"
+#include "mozIApplication.h"
+#include "nsIDOMApplicationRegistry.h"
+#include "TabParent.h"
+
+using namespace mozilla::dom;
+using namespace mozilla::services;
+
+namespace mozilla {
+
+bool
+AppProcessHasPermission(PBrowserParent* aActor, const char* aPermission)
+{
+  if (!aActor) {
+    NS_WARNING("Testing permissions for null actor");
+    return false;
+  }
+
+  TabParent* tab = static_cast<TabParent*>(aActor);
+  nsCOMPtr<mozIApplication> app = tab->GetApp();
+  // isBrowser frames inherit their app descriptor to identify their
+  // data storage, but they don't inherit the permissions associated
+  // with that descriptor.
+  if (!app || tab->IsBrowserElement()) {
+    return false;
+  }
+
+  bool hasPermission = false;
+  return (NS_SUCCEEDED(app->HasPermission(aPermission, &hasPermission)) &&
+          hasPermission);
+}
+
+bool
+AppProcessHasPermission(PContentParent* aActor, const char* aPermission)
+{
+  const InfallibleTArray<PBrowserParent*>& browsers =
+    aActor->ManagedPBrowserParent();
+  for (uint32_t i = 0; i < browsers.Length(); ++i) {
+    if (AppProcessHasPermission(browsers[i], aPermission)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+} // namespace mozilla

dom/ipc/AppProcessPermissions.h

@@ -0,0 +1,43 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_Capabilities_h
+#define mozilla_Capabilities_h
+
+namespace mozilla {
+
+namespace dom {
+class PBrowserParent;
+class PContentParent;
+}
+
+/**
+ * Return true iff the specified browser has the specified capability.
+ */
+bool
+AppProcessHasPermissions(mozilla::dom::PBrowserParent* aActor,
+                         const char* aPermission);
+
+/**
+ * Return true iff any of the PBrowsers loaded in this content process
+ * has the specified capability.
+ */
+bool
+AppProcessHasPermission(mozilla::dom::PContentParent* aActor,
+                        const char* aPermission);
+
+// NB: when adding capability checks for other IPDL actors, please add
+// them to this file and have them delegate to the two functions above
+// as appropriate.  For example,
+//
+//   bool AppProcessHasCapability(PNeckoParent* aActor) {
+//     return AppProcessHasCapability(aActor->Manager());
+//   }
+
+} // namespace mozilla
+
+#endif // mozilla_Capabilities_h

dom/ipc/Makefile.in

@@ -23,10 +23,15 @@ endif
 EXPORTS = PCOMContentPermissionRequestChild.h
 
 EXPORTS_NAMESPACES = \
+  mozilla \
   mozilla/dom \
   mozilla/dom/ipc \
   $(NULL)
 
+EXPORTS_mozilla = \
+  AppProcessPermissions.h \
+  $(NULL)
+
 EXPORTS_mozilla/dom = \
   ContentChild.h \
   ContentParent.h \
@@ -47,6 +52,7 @@ EXPORTS_mozilla/dom/ipc = \
   $(NULL)
 
 CPPSRCS = \
+  AppProcessPermissions.cpp \
   Blob.cpp \
   ContentProcess.cpp \
   ContentParent.cpp \