The Tor Browser: js/ipc/JavaScriptParent.cpp@b8a032363ba2 (annotated)

js/ipc/JavaScriptParent.cpp@b8a032363ba2 (annotated)

js/ipc/JavaScriptParent.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  * vim: set ts=4 sw=4 et tw=80:
  *
  * 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 "JavaScriptParent.h"
 #include "mozilla/dom/ContentParent.h"
 #include "nsJSUtils.h"
 #include "jsfriendapi.h"
 #include "jsproxy.h"
 #include "jswrapper.h"
 #include "HeapAPI.h"
 #include "xpcprivate.h"
 #include "mozilla/Casting.h"
 using namespace js;
 using namespace JS;
 using namespace mozilla;
 using namespace mozilla::jsipc;
 using namespace mozilla::dom;
 JavaScriptParent::JavaScriptParent()
   : refcount_(1),
     inactive_(false)
 {
 }
 static inline JavaScriptParent *
 ParentOf(JSObject *obj)
 {
     MOZ_ASSERT(JavaScriptParent::IsCPOW(obj));
     return reinterpret_cast<JavaScriptParent *>(GetProxyExtra(obj, 0).toPrivate());
 }
 ObjectId
 JavaScriptParent::idOf(JSObject *obj)
 {
     MOZ_ASSERT(JavaScriptParent::IsCPOW(obj));
     Value v = GetProxyExtra(obj, 1);
     MOZ_ASSERT(v.isDouble());
     ObjectId objId = BitwiseCast<uint64_t>(v.toDouble());
     MOZ_ASSERT(findObject(objId) == obj);
     MOZ_ASSERT(objId);
     return objId;
 }
 int sCPOWProxyHandler;
 class CPOWProxyHandler : public BaseProxyHandler
 {
   public:
     CPOWProxyHandler()
       : BaseProxyHandler(&sCPOWProxyHandler) {}
     virtual ~CPOWProxyHandler() {}
     virtual bool finalizeInBackground(Value priv) MOZ_OVERRIDE {
         return false;
     }
     virtual bool preventExtensions(JSContext *cx, HandleObject proxy) MOZ_OVERRIDE;
     virtual bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
                                        MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
     virtual bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
                                           MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
     virtual bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
                                 MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
     virtual bool getOwnPropertyNames(JSContext *cx, HandleObject proxy,
                                      AutoIdVector &props) MOZ_OVERRIDE;
     virtual bool delete_(JSContext *cx, HandleObject proxy, HandleId id, bool *bp) MOZ_OVERRIDE;
     virtual bool enumerate(JSContext *cx, HandleObject proxy, AutoIdVector &props) MOZ_OVERRIDE;
     virtual bool has(JSContext *cx, HandleObject proxy, HandleId id, bool *bp) MOZ_OVERRIDE;
     virtual bool hasOwn(JSContext *cx, HandleObject proxy, HandleId id, bool *bp) MOZ_OVERRIDE;
     virtual bool get(JSContext *cx, HandleObject proxy, HandleObject receiver,
                      HandleId id, MutableHandleValue vp) MOZ_OVERRIDE;
     virtual bool set(JSContext *cx, JS::HandleObject proxy, JS::HandleObject receiver,
                      JS::HandleId id, bool strict, JS::MutableHandleValue vp) MOZ_OVERRIDE;
     virtual bool keys(JSContext *cx, HandleObject proxy, AutoIdVector &props) MOZ_OVERRIDE;
     virtual bool isExtensible(JSContext *cx, HandleObject proxy, bool *extensible) MOZ_OVERRIDE;
     virtual bool call(JSContext *cx, HandleObject proxy, const CallArgs &args) MOZ_OVERRIDE;
     virtual bool objectClassIs(HandleObject obj, js::ESClassValue classValue, JSContext *cx) MOZ_OVERRIDE;
     virtual const char* className(JSContext *cx, HandleObject proxy) MOZ_OVERRIDE;
     virtual void finalize(JSFreeOp *fop, JSObject *proxy) MOZ_OVERRIDE;
     static CPOWProxyHandler singleton;
 };
 CPOWProxyHandler CPOWProxyHandler::singleton;
 #define FORWARD(call, args)                                             \
     JavaScriptParent *parent = ParentOf(proxy);                         \
     if (!parent->active()) {                                            \
         JS_ReportError(cx, "cannot use a CPOW whose process is gone");  \
         return false;                                                   \
     }                                                                   \
     return parent->call args;
 bool
 CPOWProxyHandler::preventExtensions(JSContext *cx, HandleObject proxy)
 {
     FORWARD(preventExtensions, (cx, proxy));
 }
 bool
 JavaScriptParent::preventExtensions(JSContext *cx, HandleObject proxy)
 {
     ObjectId objId = idOf(proxy);
     ReturnStatus status;
     if (!CallPreventExtensions(objId, &status))
         return ipcfail(cx);
     return ok(cx, status);
 }
 bool
 CPOWProxyHandler::getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
                                         MutableHandle<JSPropertyDescriptor> desc)
 {
     FORWARD(getPropertyDescriptor, (cx, proxy, id, desc));
 }
 bool
 JavaScriptParent::getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
                                         MutableHandle<JSPropertyDescriptor> desc)
 {
     ObjectId objId = idOf(proxy);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     ReturnStatus status;
     PPropertyDescriptor result;
     if (!CallGetPropertyDescriptor(objId, idstr, &status, &result))
         return ipcfail(cx);
     if (!ok(cx, status))
         return false;
     return toDescriptor(cx, result, desc);
 }
 bool
 CPOWProxyHandler::getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy,
                                            HandleId id, MutableHandle<JSPropertyDescriptor> desc)
 {
     FORWARD(getOwnPropertyDescriptor, (cx, proxy, id, desc));
 }
 bool
 JavaScriptParent::getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
                                            MutableHandle<JSPropertyDescriptor> desc)
 {
     ObjectId objId = idOf(proxy);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     ReturnStatus status;
     PPropertyDescriptor result;
     if (!CallGetOwnPropertyDescriptor(objId, idstr, &status, &result))
         return ipcfail(cx);
     if (!ok(cx, status))
         return false;
     return toDescriptor(cx, result, desc);
 }
 bool
 CPOWProxyHandler::defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
                                  MutableHandle<JSPropertyDescriptor> desc)
 {
     FORWARD(defineProperty, (cx, proxy, id, desc));
 }
 bool
 JavaScriptParent::defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
                                  MutableHandle<JSPropertyDescriptor> desc)
 {
     ObjectId objId = idOf(proxy);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     PPropertyDescriptor descriptor;
     if (!fromDescriptor(cx, desc, &descriptor))
         return false;
     ReturnStatus status;
     if (!CallDefineProperty(objId, idstr, descriptor, &status))
         return ipcfail(cx);
     return ok(cx, status);
 }
 bool
 CPOWProxyHandler::getOwnPropertyNames(JSContext *cx, HandleObject proxy, AutoIdVector &props)
 {
     FORWARD(getOwnPropertyNames, (cx, proxy, props));
 }
 bool
 JavaScriptParent::getOwnPropertyNames(JSContext *cx, HandleObject proxy, AutoIdVector &props)
 {
     return getPropertyNames(cx, proxy, JSITER_OWNONLY | JSITER_HIDDEN, props);
 }
 bool
 CPOWProxyHandler::delete_(JSContext *cx, HandleObject proxy, HandleId id, bool *bp)
 {
     FORWARD(delete_, (cx, proxy, id, bp));
 }
 bool
 JavaScriptParent::delete_(JSContext *cx, HandleObject proxy, HandleId id, bool *bp)
 {
     ObjectId objId = idOf(proxy);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     ReturnStatus status;
     if (!CallDelete(objId, idstr, &status, bp))
         return ipcfail(cx);
     return ok(cx, status);
 }
 bool
 CPOWProxyHandler::enumerate(JSContext *cx, HandleObject proxy, AutoIdVector &props)
 {
     FORWARD(enumerate, (cx, proxy, props));
 }
 bool
 JavaScriptParent::enumerate(JSContext *cx, HandleObject proxy, AutoIdVector &props)
 {
     return getPropertyNames(cx, proxy, 0, props);
 }
 bool
 CPOWProxyHandler::has(JSContext *cx, HandleObject proxy, HandleId id, bool *bp)
 {
     FORWARD(has, (cx, proxy, id, bp));
 }
 bool
 JavaScriptParent::has(JSContext *cx, HandleObject proxy, HandleId id, bool *bp)
 {
     ObjectId objId = idOf(proxy);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     ReturnStatus status;
     if (!CallHas(objId, idstr, &status, bp))
         return ipcfail(cx);
     return ok(cx, status);
 }
 bool
 CPOWProxyHandler::hasOwn(JSContext *cx, HandleObject proxy, HandleId id, bool *bp)
 {
     FORWARD(hasOwn, (cx, proxy, id, bp));
 }
 bool
 JavaScriptParent::hasOwn(JSContext *cx, HandleObject proxy, HandleId id, bool *bp)
 {
     ObjectId objId = idOf(proxy);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     ReturnStatus status;
     if (!CallHasOwn(objId, idstr, &status, bp))
         return ipcfail(cx);
     return !!ok(cx, status);
 }
 bool
 CPOWProxyHandler::get(JSContext *cx, HandleObject proxy, HandleObject receiver,
                       HandleId id, MutableHandleValue vp)
 {
     FORWARD(get, (cx, proxy, receiver, id, vp));
 }
 bool
 JavaScriptParent::get(JSContext *cx, HandleObject proxy, HandleObject receiver,
                       HandleId id, MutableHandleValue vp)
 {
     ObjectId objId = idOf(proxy);
     ObjectId receiverId = idOf(receiver);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     JSVariant val;
     ReturnStatus status;
     if (!CallGet(objId, receiverId, idstr, &status, &val))
         return ipcfail(cx);
     if (!ok(cx, status))
         return false;
     return toValue(cx, val, vp);
 }
 bool
 CPOWProxyHandler::set(JSContext *cx, JS::HandleObject proxy, JS::HandleObject receiver,
                       JS::HandleId id, bool strict, JS::MutableHandleValue vp)
 {
     FORWARD(set, (cx, proxy, receiver, id, strict, vp));
 }
 bool
 JavaScriptParent::set(JSContext *cx, JS::HandleObject proxy, JS::HandleObject receiver,
                       JS::HandleId id, bool strict, JS::MutableHandleValue vp)
 {
     ObjectId objId = idOf(proxy);
     ObjectId receiverId = idOf(receiver);
     nsString idstr;
     if (!convertIdToGeckoString(cx, id, &idstr))
         return false;
     JSVariant val;
     if (!toVariant(cx, vp, &val))
         return false;
     ReturnStatus status;
     JSVariant result;
     if (!CallSet(objId, receiverId, idstr, strict, val, &status, &result))
         return ipcfail(cx);
     if (!ok(cx, status))
         return false;
     return toValue(cx, result, vp);
 }
 bool
 CPOWProxyHandler::keys(JSContext *cx, HandleObject proxy, AutoIdVector &props)
 {
     FORWARD(keys, (cx, proxy, props));
 }
 bool
 JavaScriptParent::keys(JSContext *cx, HandleObject proxy, AutoIdVector &props)
 {
     return getPropertyNames(cx, proxy, JSITER_OWNONLY, props);
 }
 bool
 CPOWProxyHandler::isExtensible(JSContext *cx, HandleObject proxy, bool *extensible)
 {
     FORWARD(isExtensible, (cx, proxy, extensible));
 }
 bool
 JavaScriptParent::isExtensible(JSContext *cx, HandleObject proxy, bool *extensible)
 {
     ObjectId objId = idOf(proxy);
     ReturnStatus status;
     if (!CallIsExtensible(objId, &status, extensible))
         return ipcfail(cx);
     return ok(cx, status);
 }
 bool
 CPOWProxyHandler::call(JSContext *cx, HandleObject proxy, const CallArgs &args)
 {
     FORWARD(call, (cx, proxy, args));
 }
 bool
 JavaScriptParent::call(JSContext *cx, HandleObject proxy, const CallArgs &args)
 {
     ObjectId objId = idOf(proxy);
     InfallibleTArray<JSParam> vals;
     AutoValueVector outobjects(cx);
     RootedValue v(cx);
     for (size_t i = 0; i < args.length() + 2; i++) {
         v = args.base()[i];
         if (v.isObject()) {
             RootedObject obj(cx, &v.toObject());
             if (xpc::IsOutObject(cx, obj)) {
                 // Make sure it is not an in-out object.
                 bool found;
                 if (!JS_HasProperty(cx, obj, "value", &found))
                     return false;
                 if (found) {
                     JS_ReportError(cx, "in-out objects cannot be sent via CPOWs yet");
                     return false;
                 }
                 vals.AppendElement(JSParam(void_t()));
                 if (!outobjects.append(ObjectValue(*obj)))
                     return false;
                 continue;
             }
         }
         JSVariant val;
         if (!toVariant(cx, v, &val))
             return false;
         vals.AppendElement(JSParam(val));
     }
     JSVariant result;
     ReturnStatus status;
     InfallibleTArray<JSParam> outparams;
     if (!CallCall(objId, vals, &status, &result, &outparams))
         return ipcfail(cx);
     if (!ok(cx, status))
         return false;
     if (outparams.Length() != outobjects.length())
         return ipcfail(cx);
     RootedObject obj(cx);
     for (size_t i = 0; i < outparams.Length(); i++) {
         // Don't bother doing anything for outparams that weren't set.
         if (outparams[i].type() == JSParam::Tvoid_t)
             continue;
         // Take the value the child process returned, and set it on the XPC
         // object.
         if (!toValue(cx, outparams[i], &v))
             return false;
         obj = &outobjects[i].toObject();
         if (!JS_SetProperty(cx, obj, "value", v))
             return false;
     }
     if (!toValue(cx, result, args.rval()))
         return false;
     return true;
 }
 bool
 CPOWProxyHandler::objectClassIs(HandleObject proxy, js::ESClassValue classValue, JSContext *cx)
 {
     FORWARD(objectClassIs, (cx, proxy, classValue));
 }
 bool
 JavaScriptParent::objectClassIs(JSContext *cx, HandleObject proxy, js::ESClassValue classValue)
 {
     ObjectId objId = idOf(proxy);
     // This function is assumed infallible, so we just return false if the IPC
     // channel fails.
     bool result;
     if (!CallObjectClassIs(objId, classValue, &result))
         return false;
     return result;
 }
 const char *
 CPOWProxyHandler::className(JSContext *cx, HandleObject proxy)
 {
     JavaScriptParent *parent = ParentOf(proxy);
     if (!parent->active())
         return "<dead CPOW>";
     return parent->className(cx, proxy);
 }
 const char *
 JavaScriptParent::className(JSContext *cx, HandleObject proxy)
 {
     ObjectId objId = idOf(proxy);
     nsString name;
     if (!CallClassName(objId, &name))
         return "<error>";
     return ToNewCString(name);
 }
 void
 CPOWProxyHandler::finalize(JSFreeOp *fop, JSObject *proxy)
 {
     ParentOf(proxy)->drop(proxy);
 }
 void
 JavaScriptParent::drop(JSObject *obj)
 {
     ObjectId objId = idOf(obj);
     objects_.remove(objId);
     if (!inactive_ && !SendDropObject(objId))
         (void)0;
     decref();
 }
 bool
 JavaScriptParent::init()
 {
     if (!JavaScriptShared::init())
         return false;
     return true;
 }
 bool
 JavaScriptParent::makeId(JSContext *cx, JSObject *obj, ObjectId *idp)
 {
     obj = js::CheckedUnwrap(obj, false);
     if (!obj || !IsProxy(obj) || GetProxyHandler(obj) != &CPOWProxyHandler::singleton) {
         JS_ReportError(cx, "cannot ipc non-cpow object");
         return false;
     }
     *idp = idOf(obj);
     return true;
 }
 bool
 JavaScriptParent::getPropertyNames(JSContext *cx, HandleObject proxy, uint32_t flags, AutoIdVector &props)
 {
     ObjectId objId = idOf(proxy);
     ReturnStatus status;
     InfallibleTArray<nsString> names;
     if (!CallGetPropertyNames(objId, flags, &status, &names))
         return ipcfail(cx);
     if (!ok(cx, status))
         return false;
     for (size_t i = 0; i < names.Length(); i++) {
         RootedId name(cx);
         if (!convertGeckoStringToId(cx, names[i], &name))
             return false;
         if (!props.append(name))
             return false;
     }
     return true;
 }
 JSObject *
 JavaScriptParent::unwrap(JSContext *cx, ObjectId objId)
 {
     RootedObject obj(cx, findObject(objId));
     if (obj) {
         if (!JS_WrapObject(cx, &obj))
             return nullptr;
         return obj;
     }
     if (objId > MAX_CPOW_IDS) {
         JS_ReportError(cx, "unusable CPOW id");
         return nullptr;
     }
     bool callable = !!(objId & OBJECT_IS_CALLABLE);
     RootedObject global(cx, JS::CurrentGlobalOrNull(cx));
     RootedValue v(cx, UndefinedValue());
     ProxyOptions options;
     options.selectDefaultClass(callable);
     obj = NewProxyObject(cx,
                          &CPOWProxyHandler::singleton,
                          v,
                          nullptr,
                          global,
                          options);
     if (!obj)
         return nullptr;
     if (!objects_.add(objId, obj))
         return nullptr;
     // Incref once we know the decref will be called.
     incref();
     SetProxyExtra(obj, 0, PrivateValue(this));
     SetProxyExtra(obj, 1, DoubleValue(BitwiseCast<double>(objId)));
     return obj;
 }
 bool
 JavaScriptParent::ipcfail(JSContext *cx)
 {
     JS_ReportError(cx, "child process crashed or timedout");
     return false;
 }
 bool
 JavaScriptParent::ok(JSContext *cx, const ReturnStatus &status)
 {
     if (status.type() == ReturnStatus::TReturnSuccess)
         return true;
     if (status.type() == ReturnStatus::TReturnStopIteration)
         return JS_ThrowStopIteration(cx);
     RootedValue exn(cx);
     if (!toValue(cx, status.get_ReturnException().exn(), &exn))
         return false;
     JS_SetPendingException(cx, exn);
     return false;
 }
 void
 JavaScriptParent::decref()
 {
     refcount_--;
     if (!refcount_)
         delete this;
 }
 void
 JavaScriptParent::incref()
 {
     refcount_++;
 }
 void
 JavaScriptParent::ActorDestroy(ActorDestroyReason why)
 {
     inactive_ = true;
 }
 /* static */ bool
 JavaScriptParent::IsCPOW(JSObject *obj)
 {
     return IsProxy(obj) && GetProxyHandler(obj) == &CPOWProxyHandler::singleton;
 }
 /* static */ nsresult
 JavaScriptParent::InstanceOf(JSObject *proxy, const nsID *id, bool *bp)
 {
     JavaScriptParent *parent = ParentOf(proxy);
     if (!parent->active())
         return NS_ERROR_UNEXPECTED;
     return parent->instanceOf(proxy, id, bp);
 }
 nsresult
 JavaScriptParent::instanceOf(JSObject *obj, const nsID *id, bool *bp)
 {
     ObjectId objId = idOf(obj);
     JSIID iid;
     ConvertID(*id, &iid);
     ReturnStatus status;
     if (!CallInstanceOf(objId, iid, &status, bp))
         return NS_ERROR_UNEXPECTED;
     if (status.type() != ReturnStatus::TReturnSuccess)
         return NS_ERROR_UNEXPECTED;
     return NS_OK;
 }
 /* static */ bool
 JavaScriptParent::DOMInstanceOf(JSContext *cx, JSObject *proxy, int prototypeID, int depth, bool *bp)
 {
     FORWARD(domInstanceOf, (cx, proxy, prototypeID, depth, bp));
 }
 bool
 JavaScriptParent::domInstanceOf(JSContext *cx, JSObject *obj, int prototypeID, int depth, bool *bp)
 {
     ObjectId objId = idOf(obj);
     ReturnStatus status;
     if (!CallDOMInstanceOf(objId, prototypeID, depth, &status, bp))
         return ipcfail(cx);
     return ok(cx, status);
 }
 mozilla::ipc::IProtocol*
 JavaScriptParent::CloneProtocol(Channel* aChannel, ProtocolCloneContext* aCtx)
 {
     ContentParent *contentParent = aCtx->GetContentParent();
     nsAutoPtr<PJavaScriptParent> actor(contentParent->AllocPJavaScriptParent());
     if (!actor || !contentParent->RecvPJavaScriptConstructor(actor)) {
         return nullptr;
     }
     return actor.forget();
 }

The Tor Browser / annotate

js/ipc/JavaScriptParent.cpp@b8a032363ba2 (annotated)

js/ipc/JavaScriptParent.cpp