Bug 1525720, part 5 - Redirect nsIHttpChannel using content process ID instead of nsIRemoteTab. r=valentin

This code currently works for remote subframes assuming that nsIRemoteTab is implemented
by BrowserParent, but will break when nsIRemoteTab is only for a top-level BrowserParent.

What this code really wants is a content process ID to retarget the channel to. This
commit switches the interfaces to pass this around instead of nsIRemoteTab.

Differential Revision: https://phabricator.services.mozilla.com/D31435

--HG--
extra : rebase_source : be3303c2d38d704a6a1817fa45fd76700fae6287
extra : histedit_source : c7bf1e496f4328acc9ee70fcccdff98ea2cce5df

browser/components/sessionstore/SessionStore.jsm

@@ -2331,7 +2331,7 @@ var SessionStoreInternal = {
     // Tell our caller to redirect the load into this newly created process.
     let remoteTab = aBrowser.frameLoader.remoteTab;
     debug(`[process-switch]: new tabID: ${remoteTab.tabId}`);
-    return remoteTab;
+    return remoteTab.contentProcessId;
   },
 
   /**

dom/chrome-webidl/WindowGlobalActors.webidl

@@ -35,7 +35,7 @@ interface WindowGlobalParent {
   JSWindowActorParent getActor(DOMString name);
 
   [Throws]
-  Promise<RemoteTab> changeFrameRemoteness(
+  Promise<unsigned long long> changeFrameRemoteness(
     BrowsingContext? bc, DOMString remoteType,
     unsigned long long pendingSwitchId);
 };

dom/interfaces/base/nsIRemoteTab.idl

@@ -57,6 +57,8 @@ interface nsIRemoteTab : nsISupports
 
   readonly attribute uint64_t tabId;
 
+  readonly attribute uint64_t contentProcessId;
+
   /**
    * The OS level process Id of the related child process.
    */

dom/ipc/BrowserParent.cpp

@@ -3188,6 +3188,12 @@ BrowserParent::GetTabId(uint64_t* aId) {
   return NS_OK;
 }
 
+NS_IMETHODIMP
+BrowserParent::GetContentProcessId(uint64_t* aId) {
+  *aId = Manager()->GetChildID();
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 BrowserParent::GetOsPid(int32_t* aId) {
   *aId = Manager()->Pid();

dom/ipc/WindowGlobalParent.cpp

@@ -277,12 +277,13 @@ already_AddRefed<Promise> WindowGlobalParent::ChangeFrameRemoteness(
         }
 
         // If we got a BrowserBridgeParent, the frame is out-of-process, so pull
-        // our target BrowserParent off of it. Otherwise, it's an in-process
+        // our target content process off of it. Otherwise, it's an in-process
         // frame, so we can directly use ours.
         if (bridge) {
-          promise->MaybeResolve(bridge->GetBrowserParent());
+          promise->MaybeResolve(
+              bridge->GetBrowserParent()->Manager()->ChildID());
         } else {
-          promise->MaybeResolve(browserParent);
+          promise->MaybeResolve(browserParent->Manager()->ChildID());
         }
       };
 

netwerk/protocol/http/HttpChannelParentListener.cpp

@@ -8,6 +8,8 @@
 #include "HttpLog.h"
 
 #include "HttpChannelParentListener.h"
+#include "mozilla/dom/ContentParent.h"
+#include "mozilla/dom/ContentProcessManager.h"
 #include "mozilla/dom/ServiceWorkerInterceptController.h"
 #include "mozilla/dom/ServiceWorkerUtils.h"
 #include "mozilla/net/HttpChannelParent.h"
@@ -158,13 +160,14 @@ nsresult HttpChannelParentListener::TriggerCrossProcessRedirect(
 
   nsCOMPtr<nsIChannel> channel = aChannel;
   RefPtr<nsHttpChannel> httpChannel = do_QueryObject(channel);
-  RefPtr<nsHttpChannel::TabPromise> p = httpChannel->TakeRedirectTabPromise();
+  RefPtr<nsHttpChannel::ContentProcessIdPromise> p =
+      httpChannel->TakeRedirectContentProcessIdPromise();
   nsCOMPtr<nsILoadInfo> loadInfo = aLoadInfo;
 
   RefPtr<HttpChannelParentListener> self = this;
   p->Then(
       GetMainThreadSerialEventTarget(), __func__,
-      [=](nsCOMPtr<nsIRemoteTab> tp) {
+      [=](uint64_t cpId) {
         nsresult rv;
 
         // Register the new channel and obtain id for it
@@ -199,8 +202,13 @@ nsresult HttpChannelParentListener::TriggerCrossProcessRedirect(
           MOZ_ALWAYS_SUCCEEDS(internalChannel->GetRedirectMode(&redirectMode));
         }
 
-        dom::BrowserParent* browserParent = dom::BrowserParent::GetFrom(tp);
-        auto result = browserParent->Manager()->SendCrossProcessRedirect(
+        dom::ContentParent* cp =
+            dom::ContentProcessManager::GetSingleton()->GetContentProcessById(
+                ContentParentId{cpId});
+        if (!cp) {
+          return NS_ERROR_UNEXPECTED;
+        }
+        auto result = cp->SendCrossProcessRedirect(
             self->mRedirectChannelId, uri, newLoadFlags, loadInfoArgs,
             channelId, originalURI, aIdentifier, redirectMode);
 

netwerk/protocol/http/nsHttpChannel.cpp

@@ -128,6 +128,7 @@
 #include "HttpTrafficAnalyzer.h"
 #include "mozilla/dom/CanonicalBrowsingContext.h"
 #include "mozilla/dom/WindowGlobalParent.h"
+#include "js/Conversions.h"
 
 #ifdef MOZ_TASK_TRACER
 #  include "GeckoTaskTracer.h"
@@ -2569,7 +2570,7 @@ nsresult nsHttpChannel::ContinueProcessResponse1() {
     // notify "http-on-may-change-process" observers
     gHttpHandler->OnMayChangeProcess(this);
 
-    if (mRedirectTabPromise) {
+    if (mRedirectContentProcessIdPromise) {
       MOZ_ASSERT(!mOnStartRequestCalled);
 
       PushRedirectAsyncFunc(&nsHttpChannel::ContinueProcessResponse2);
@@ -7244,10 +7245,11 @@ nsHttpChannel::GetRequestMethod(nsACString& aMethod) {
 class DomPromiseListener final : dom::PromiseNativeHandler {
   NS_DECL_ISUPPORTS
 
-  static RefPtr<nsHttpChannel::TabPromise> Create(dom::Promise* aDOMPromise) {
+  static RefPtr<nsHttpChannel::ContentProcessIdPromise> Create(
+      dom::Promise* aDOMPromise) {
     MOZ_ASSERT(aDOMPromise);
     RefPtr<DomPromiseListener> handler = new DomPromiseListener();
-    RefPtr<nsHttpChannel::TabPromise> promise =
+    RefPtr<nsHttpChannel::ContentProcessIdPromise> promise =
         handler->mPromiseHolder.Ensure(__func__);
     aDOMPromise->AppendNativeHandler(handler);
     return promise;
@@ -7255,15 +7257,12 @@ class DomPromiseListener final : dom::PromiseNativeHandler {
 
   virtual void ResolvedCallback(JSContext* aCx,
                                 JS::Handle<JS::Value> aValue) override {
-    nsCOMPtr<nsIRemoteTab> browserParent;
-    JS::Rooted<JSObject*> obj(aCx, &aValue.toObject());
-    nsresult rv =
-        UnwrapArg<nsIRemoteTab>(aCx, obj, getter_AddRefs(browserParent));
-    if (NS_FAILED(rv)) {
-      mPromiseHolder.Reject(rv, __func__);
+    uint64_t cpId;
+    if (!JS::ToUint64(aCx, aValue, &cpId)) {
+      mPromiseHolder.Reject(NS_ERROR_FAILURE, __func__);
       return;
     }
-    mPromiseHolder.Resolve(browserParent, __func__);
+    mPromiseHolder.Resolve(cpId, __func__);
   }
 
   virtual void RejectedCallback(JSContext* aCx,
@@ -7278,15 +7277,15 @@ class DomPromiseListener final : dom::PromiseNativeHandler {
  private:
   DomPromiseListener() = default;
   ~DomPromiseListener() = default;
-  MozPromiseHolder<nsHttpChannel::TabPromise> mPromiseHolder;
+  MozPromiseHolder<nsHttpChannel::ContentProcessIdPromise> mPromiseHolder;
 };
 
 NS_IMPL_ISUPPORTS0(DomPromiseListener)
 
-NS_IMETHODIMP nsHttpChannel::SwitchProcessTo(dom::Promise* aTabPromise,
-                                             uint64_t aIdentifier) {
+NS_IMETHODIMP nsHttpChannel::SwitchProcessTo(
+    dom::Promise* aContentProcessIdPromise, uint64_t aIdentifier) {
   MOZ_ASSERT(NS_IsMainThread());
-  NS_ENSURE_ARG(aTabPromise);
+  NS_ENSURE_ARG(aContentProcessIdPromise);
 
   LOG(("nsHttpChannel::SwitchProcessTo [this=%p]", this));
   LogCallingScriptLocation(this);
@@ -7294,7 +7293,8 @@ NS_IMETHODIMP nsHttpChannel::SwitchProcessTo(dom::Promise* aTabPromise,
   // We cannot do this after OnStartRequest of the listener has been called.
   NS_ENSURE_FALSE(mOnStartRequestCalled, NS_ERROR_NOT_AVAILABLE);
 
-  mRedirectTabPromise = DomPromiseListener::Create(aTabPromise);
+  mRedirectContentProcessIdPromise =
+      DomPromiseListener::Create(aContentProcessIdPromise);
   mCrossProcessRedirectIdentifier = aIdentifier;
   return NS_OK;
 }
@@ -7645,7 +7645,7 @@ nsHttpChannel::OnStartRequest(nsIRequest* request) {
     // notify "http-on-may-change-process" observers
     gHttpHandler->OnMayChangeProcess(this);
 
-    if (mRedirectTabPromise) {
+    if (mRedirectContentProcessIdPromise) {
       PushRedirectAsyncFunc(&nsHttpChannel::ContinueOnStartRequest1);
       rv = StartCrossProcessRedirect();
       if (NS_SUCCEEDED(rv)) {

netwerk/protocol/http/nsHttpChannel.h

@@ -286,9 +286,10 @@ class nsHttpChannel final : public HttpBaseChannel,
   }
   TransactionObserver* GetTransactionObserver() { return mTransactionObserver; }
 
-  typedef MozPromise<nsCOMPtr<nsIRemoteTab>, nsresult, false> TabPromise;
-  already_AddRefed<TabPromise> TakeRedirectTabPromise() {
-    return mRedirectTabPromise.forget();
+  typedef MozPromise<uint64_t, nsresult, false> ContentProcessIdPromise;
+  already_AddRefed<ContentProcessIdPromise>
+  TakeRedirectContentProcessIdPromise() {
+    return mRedirectContentProcessIdPromise.forget();
   }
   uint64_t CrossProcessRedirectIdentifier() {
     return mCrossProcessRedirectIdentifier;
@@ -576,7 +577,7 @@ class nsHttpChannel final : public HttpBaseChannel,
 
   // The associated childChannel is getting relocated to another process.
   // This promise will be resolved when that process is set up.
-  RefPtr<TabPromise> mRedirectTabPromise;
+  RefPtr<ContentProcessIdPromise> mRedirectContentProcessIdPromise;
   // This identifier is passed to the childChannel in order to identify it.
   uint64_t mCrossProcessRedirectIdentifier = 0;
 

netwerk/test/browser/browser_cross_process_redirect.js

@@ -70,7 +70,7 @@ ProcessChooser.prototype = {
       // Can asyncly create a tab, or can resolve with a tab that was
       // previously created.
       info("resolving");
-      resolve(self.remoteTab);
+      resolve(self.remoteTab.contentProcessId);
     });
 
     info("calling switchprocessto");