Bug 904298 - Implement mozilla::{AssertAppPrincipal,CheckPermission}. r=sicking

dom/ipc/AppProcessChecker.cpp

@@ -6,15 +6,26 @@
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "AppProcessChecker.h"
+#include "nsIPermissionManager.h"
 #ifdef MOZ_CHILD_PERMISSIONS
 #include "ContentParent.h"
 #include "mozIApplication.h"
 #include "mozilla/hal_sandbox/PHalParent.h"
+#include "nsIAppsService.h"
+#include "nsIPrincipal.h"
+#include "nsIScriptSecurityManager.h"
+#include "nsIURI.h"
+#include "nsServiceManagerUtils.h"
 #include "TabParent.h"
 
+#include <algorithm>
+
 using namespace mozilla::dom;
 using namespace mozilla::hal_sandbox;
 using namespace mozilla::services;
+#else
+class PContentParent;
+class nsIPrincipal;
 #endif
 
 namespace mozilla {
@@ -126,6 +137,99 @@ AssertAppProcess(PHalParent* aActor,
   return AssertAppProcess(aActor->Manager(), aType, aCapability);
 }
 
+bool
+AssertAppPrincipal(PContentParent* aActor,
+                   nsIPrincipal* aPrincipal)
+{
+  if (!aPrincipal) {
+    NS_WARNING("Principal is invalid, killing app process");
+    static_cast<ContentParent*>(aActor)->KillHard();
+    return false;
+  }
+
+  uint32_t principalAppId = aPrincipal->GetAppId();
+  bool inBrowserElement = aPrincipal->GetIsInBrowserElement();
+
+  // Check if the permission's appId matches a child we manage.
+  const InfallibleTArray<PBrowserParent*>& browsers =
+    aActor->ManagedPBrowserParent();
+  for (uint32_t i = 0; i < browsers.Length(); ++i) {
+    TabParent* tab = static_cast<TabParent*>(browsers[i]);
+    if (tab->OwnOrContainingAppId() == principalAppId) {
+      // If the child only runs inBrowserElement content and the principal claims
+      // it's not in a browser element, it's lying.
+      if (!tab->IsBrowserElement() || inBrowserElement) {
+        return true;
+      }
+      break;
+    }
+  }
+
+  NS_WARNING("Principal is invalid, killing app process");
+  static_cast<ContentParent*>(aActor)->KillHard();
+  return false;
+}
+
+already_AddRefed<nsIPrincipal>
+GetAppPrincipal(uint32_t aAppId)
+{
+  nsCOMPtr<nsIAppsService> appsService = do_GetService(APPS_SERVICE_CONTRACTID);
+
+  nsIURI* uri;
+  nsresult rv = appsService->GetManifestURLByLocalId(aAppId);
+  NS_ENSURE_SUCCESS(rv, nullptr);
+
+  nsCOMPtr<nsIScriptSecurityManager> secMan =
+    do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID);
+
+  nsIPrincipal* appPrincipal;
+  rv = secMan->GetAppCodebasePrincipal(uri, aAppId, false, &appPrincipal);
+  NS_ENSURE_SUCCESS(rv, nullptr);
+  return appPrincipal;
+}
+
+uint32_t
+CheckPermission(PContentParent* aActor,
+                nsIPrincipal* aPrincipal,
+                const char* aPermission)
+{
+  if (!AssertAppPrincipal(aActor, aPrincipal)) {
+    return nsIPermissionManager::DENY_ACTION;
+  }
+
+  nsCOMPtr<nsIPermissionManager> pm =
+    do_GetService(NS_PERMISSIONMANAGER_CONTRACTID);
+  NS_ENSURE_TRUE(pm, nsIPermissionManager::DENY_ACTION);
+
+  // Make sure that `aPermission' is an app permission before checking the origin.
+  nsCOMPtr<nsIPrincipal> appPrincipal = GetAppPrincipal(aPrincipal->GetAppId());
+  uint32_t appPerm = nsIPermissionManager::UNKNOWN_ACTION;
+  nsresult rv = pm->TestExactPermissionFromPrincipal(appPrincipal, aPermission, &appPerm);
+  NS_ENSURE_SUCCESS(rv, nsIPermissionManager::UNKNOWN_ACTION);
+  if (appPerm == nsIPermissionManager::UNKNOWN_ACTION ||
+      appPerm == nsIPermissionManager::DENY_ACTION) {
+    return appPerm;
+  }
+
+  uint32_t permission = nsIPermissionManager::UNKNOWN_ACTION;
+  rv = pm->TestExactPermissionFromPrincipal(aPrincipal, aPermission, &permission);
+  NS_ENSURE_SUCCESS(rv, nsIPermissionManager::UNKNOWN_ACTION);
+  if (permission == nsIPermissionManager::UNKNOWN_ACTION ||
+      permission == nsIPermissionManager::DENY_ACTION) {
+    return permission;
+  }
+
+  if (appPerm == PROMPT_ACTION || permission == PROMPT_ACTION) {
+    return PROMPT_ACTION;
+  }
+
+  if (appPerm == ALLOW_ACTION || permission == ALLOW_ACTION) {
+    return ALLOW_ACTION;
+  }
+
+  NS_RUNTIMEABORT("Invalid permission value");
+}
+
 #else
 
 bool
@@ -167,6 +271,21 @@ AssertAppProcess(mozilla::hal_sandbox::PHalParent* aActor,
   return true;
 }
 
+bool
+AssertAppPrincipal(PContentParent* aActor,
+                   nsIPrincipal* aPrincipal)
+{
+  return true;
+}
+
+uint32_t
+CheckPermission(PContentParent*,
+                nsIPrincipal*,
+                const char*)
+{
+  return nsIPermissionManager::ALLOW_ACTION;
+}
+
 #endif
 
 } // namespace mozilla

dom/ipc/AppProcessChecker.h

@@ -8,6 +8,10 @@
 #ifndef mozilla_AppProcessChecker_h
 #define mozilla_AppProcessChecker_h
 
+#include <stdint.h>
+
+class nsIPrincipal;
+
 namespace mozilla {
 
 namespace dom {
@@ -66,6 +70,21 @@ AssertAppProcess(mozilla::hal_sandbox::PHalParent* aActor,
 //     return AssertAppProcess(aActor->Manager(), aType);
 //   }
 
+bool
+AssertAppPrincipal(mozilla::dom::PContentParent* aParent,
+                   nsIPrincipal* aPrincipal);
+
+/**
+ * Check if the specified principal is valid, and return the saved permission
+ * value for permission `aPermission' on that principal.
+ * See nsIPermissionManager.idl for possible return values.
+ *
+ * nsIPermissionManager::UNKNOWN_ACTION is retuned if the principal is invalid.
+ */
+uint32_t
+CheckPermission(mozilla::dom::PContentParent* aParent,
+                nsIPrincipal* aPrincipal, const char* aPermission);
+
 /**
  * Inline function for asserting the process's permission.
  */