1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
|
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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 "mozilla/dom/JSActorManager.h"
#include "mozilla/dom/AutoEntryScript.h"
#include "mozilla/dom/JSActorService.h"
#include "mozilla/dom/PWindowGlobal.h"
#include "mozilla/ipc/ProtocolUtils.h"
#include "mozilla/AppShutdown.h"
#include "mozilla/CycleCollectedJSRuntime.h"
#include "mozilla/ScopeExit.h"
#include "mozJSModuleLoader.h"
#include "jsapi.h"
#include "js/CallAndConstruct.h" // JS::Construct
#include "js/PropertyAndElement.h" // JS_GetProperty
#include "nsContentUtils.h"
namespace mozilla::dom {
already_AddRefed<JSActor> JSActorManager::GetActor(JSContext* aCx,
const nsACString& aName,
ErrorResult& aRv) {
MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
// If our connection has been closed, return an error.
mozilla::ipc::IProtocol* nativeActor = AsNativeActor();
if (!nativeActor->CanSend()) {
aRv.ThrowInvalidStateError(nsPrintfCString(
"Cannot get actor '%s'. Native '%s' actor is destroyed.",
PromiseFlatCString(aName).get(), nativeActor->GetProtocolName()));
return nullptr;
}
// Check if this actor has already been created, and return it if it has.
if (RefPtr<JSActor> actor = mJSActors.Get(aName)) {
return actor.forget();
}
RefPtr<JSActorService> actorSvc = JSActorService::GetSingleton();
if (!actorSvc) {
aRv.ThrowInvalidStateError("JSActorService hasn't been initialized");
return nullptr;
}
// Check if this actor satisfies the requirements of the protocol
// corresponding to `aName`, and get the module which implements it.
RefPtr<JSActorProtocol> protocol =
MatchingJSActorProtocol(actorSvc, aName, aRv);
if (!protocol) {
return nullptr;
}
bool isParent = nativeActor->GetSide() == mozilla::ipc::ParentSide;
auto& side = isParent ? protocol->Parent() : protocol->Child();
// We're about to construct the actor, so make sure we're in the JSM realm
// while importing etc.
JSAutoRealm ar(aCx, xpc::PrivilegedJunkScope());
// Load the module using mozJSModuleLoader.
RefPtr loader = mozJSModuleLoader::Get();
MOZ_ASSERT(loader);
// If a module URI was provided, use it to construct an instance of the actor.
JS::Rooted<JSObject*> actorObj(aCx);
if (side.mModuleURI || side.mESModuleURI) {
JS::Rooted<JSObject*> exports(aCx);
if (side.mModuleURI) {
JS::Rooted<JSObject*> global(aCx);
aRv = loader->Import(aCx, side.mModuleURI.ref(), &global, &exports);
if (aRv.Failed()) {
return nullptr;
}
} else {
aRv = loader->ImportESModule(aCx, side.mESModuleURI.ref(), &exports);
if (aRv.Failed()) {
return nullptr;
}
}
MOZ_ASSERT(exports, "null exports!");
// Load the specific property from our module.
JS::Rooted<JS::Value> ctor(aCx);
nsAutoCString ctorName(aName);
ctorName.Append(isParent ? "Parent"_ns : "Child"_ns);
if (!JS_GetProperty(aCx, exports, ctorName.get(), &ctor)) {
aRv.NoteJSContextException(aCx);
return nullptr;
}
if (NS_WARN_IF(!ctor.isObject())) {
aRv.ThrowNotFoundError(nsPrintfCString(
"Could not find actor constructor '%s'", ctorName.get()));
return nullptr;
}
// Invoke the constructor loaded from the module.
if (!JS::Construct(aCx, ctor, JS::HandleValueArray::empty(), &actorObj)) {
aRv.NoteJSContextException(aCx);
return nullptr;
}
}
// Initialize our newly-constructed actor, and return it.
RefPtr<JSActor> actor = InitJSActor(actorObj, aName, aRv);
if (aRv.Failed()) {
return nullptr;
}
mJSActors.InsertOrUpdate(aName, RefPtr{actor});
return actor.forget();
}
already_AddRefed<JSActor> JSActorManager::GetExistingActor(
const nsACString& aName) {
if (!AsNativeActor()->CanSend()) {
return nullptr;
}
return mJSActors.Get(aName);
}
#define CHILD_DIAGNOSTIC_ASSERT(test, msg) \
do { \
if (XRE_IsParentProcess()) { \
MOZ_ASSERT(test, msg); \
} else { \
MOZ_DIAGNOSTIC_ASSERT(test, msg); \
} \
} while (0)
void JSActorManager::ReceiveRawMessage(
const JSActorMessageMeta& aMetadata,
Maybe<ipc::StructuredCloneData>&& aData,
Maybe<ipc::StructuredCloneData>&& aStack) {
MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
CrashReporter::AutoAnnotateCrashReport autoActorName(
CrashReporter::Annotation::JSActorName, aMetadata.actorName());
CrashReporter::AutoAnnotateCrashReport autoMessageName(
CrashReporter::Annotation::JSActorMessage,
NS_LossyConvertUTF16toASCII(aMetadata.messageName()));
// We're going to be running JS. Enter the privileged junk realm so we can set
// up our JS state correctly.
AutoEntryScript aes(xpc::PrivilegedJunkScope(), "JSActor message handler");
JSContext* cx = aes.cx();
// Ensure any errors reported to `error` are set on the scope, so they're
// reported.
ErrorResult error;
auto autoSetException =
MakeScopeExit([&] { Unused << error.MaybeSetPendingException(cx); });
// If an async stack was provided, set up our async stack state.
JS::Rooted<JSObject*> stack(cx);
Maybe<JS::AutoSetAsyncStackForNewCalls> stackSetter;
{
JS::Rooted<JS::Value> stackVal(cx);
if (aStack) {
aStack->Read(cx, &stackVal, error);
if (error.Failed()) {
error.SuppressException();
JS_ClearPendingException(cx);
stackVal.setUndefined();
}
}
if (stackVal.isObject()) {
stack = &stackVal.toObject();
if (!js::IsSavedFrame(stack)) {
CHILD_DIAGNOSTIC_ASSERT(false, "Stack must be a SavedFrame object");
error.ThrowDataError("Actor async stack must be a SavedFrame object");
return;
}
stackSetter.emplace(cx, stack, "JSActor query");
}
}
RefPtr<JSActor> actor = GetActor(cx, aMetadata.actorName(), error);
if (error.Failed()) {
return;
}
JS::Rooted<JS::Value> data(cx);
if (aData) {
aData->Read(cx, &data, error);
if (error.Failed()) {
CHILD_DIAGNOSTIC_ASSERT(CycleCollectedJSRuntime::Get()->OOMReported(),
"Should not receive non-decodable data");
return;
}
}
switch (aMetadata.kind()) {
case JSActorMessageKind::QueryResolve:
case JSActorMessageKind::QueryReject:
actor->ReceiveQueryReply(cx, aMetadata, data, error);
break;
case JSActorMessageKind::Message:
actor->ReceiveMessage(cx, aMetadata, data, error);
break;
case JSActorMessageKind::Query:
actor->ReceiveQuery(cx, aMetadata, data, error);
break;
default:
MOZ_ASSERT_UNREACHABLE();
}
}
void JSActorManager::JSActorWillDestroy() {
for (const auto& entry : mJSActors.Values()) {
entry->StartDestroy();
}
}
void JSActorManager::JSActorDidDestroy() {
MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
CrashReporter::AutoAnnotateCrashReport autoMessageName(
CrashReporter::Annotation::JSActorMessage, "<DidDestroy>"_ns);
// Swap the table with `mJSActors` so that we don't invalidate it while
// iterating.
const nsRefPtrHashtable<nsCStringHashKey, JSActor> actors =
std::move(mJSActors);
for (const auto& entry : actors.Values()) {
CrashReporter::AutoAnnotateCrashReport autoActorName(
CrashReporter::Annotation::JSActorName, entry->Name());
// Do not risk to run script very late in shutdown
if (!AppShutdown::IsInOrBeyond(ShutdownPhase::XPCOMShutdownFinal)) {
entry->AfterDestroy();
}
}
}
void JSActorManager::JSActorUnregister(const nsACString& aName) {
MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
RefPtr<JSActor> actor;
if (mJSActors.Remove(aName, getter_AddRefs(actor))) {
actor->AfterDestroy();
}
}
} // namespace mozilla::dom
|
