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
251
252
253
254
255
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 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 "mozilla/dom/StructuredCloneBlob.h"
#include <cstddef>
#include <cstdint>
#include <new>
#include <utility>
#include "js/StructuredClone.h"
#include "js/Value.h"
#include "js/Wrapper.h"
#include "jsapi.h"
#include "mozilla/Assertions.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/Maybe.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/BlobImpl.h"
#include "mozilla/dom/StructuredCloneHolderBinding.h"
#include "mozilla/dom/StructuredCloneTags.h"
#include "nsPrintfCString.h"
#include "xpcpublic.h"
namespace mozilla::dom {
StructuredCloneBlob::StructuredCloneBlob() {
mHolder.emplace(Holder::CloningSupported, Holder::TransferringNotSupported,
Holder::StructuredCloneScope::DifferentProcess);
}
StructuredCloneBlob::~StructuredCloneBlob() {
UnregisterWeakMemoryReporter(this);
}
/* static */
already_AddRefed<StructuredCloneBlob> StructuredCloneBlob::Constructor(
GlobalObject& aGlobal, const nsACString& aName,
const nsACString& aAnonymizedName, JS::Handle<JS::Value> aValue,
JS::Handle<JSObject*> aTargetGlobal, ErrorResult& aRv) {
JSContext* cx = aGlobal.Context();
RefPtr<StructuredCloneBlob> holder = StructuredCloneBlob::Create();
holder->mName = aName;
holder->mAnonymizedName = aAnonymizedName.IsVoid() ? aName : aAnonymizedName;
Maybe<JSAutoRealm> ar;
JS::Rooted<JS::Value> value(cx, aValue);
if (aTargetGlobal) {
// OK to unwrap if our caller (represented by cx's Realm) can do it.
JS::Rooted<JSObject*> targetGlobal(
cx, js::CheckedUnwrapDynamic(aTargetGlobal, cx));
if (!targetGlobal) {
js::ReportAccessDenied(cx);
aRv.NoteJSContextException(cx);
return nullptr;
}
ar.emplace(cx, targetGlobal);
if (!JS_WrapValue(cx, &value)) {
aRv.NoteJSContextException(cx);
return nullptr;
}
} else if (value.isObject()) {
// OK to unwrap if our caller (represented by cx's Realm) can do it.
JS::Rooted<JSObject*> obj(cx,
js::CheckedUnwrapDynamic(&value.toObject(), cx));
if (!obj) {
js::ReportAccessDenied(cx);
aRv.NoteJSContextException(cx);
return nullptr;
}
ar.emplace(cx, obj);
value = JS::ObjectValue(*obj);
}
holder->mHolder->Write(cx, value, aRv);
if (aRv.Failed()) {
return nullptr;
}
return holder.forget();
}
void StructuredCloneBlob::Deserialize(JSContext* aCx,
JS::Handle<JSObject*> aTargetScope,
bool aKeepData,
JS::MutableHandle<JS::Value> aResult,
ErrorResult& aRv) {
// OK to unwrap if our caller (represented by aCx's Realm) can do it.
JS::Rooted<JSObject*> scope(aCx, js::CheckedUnwrapDynamic(aTargetScope, aCx));
if (!scope) {
js::ReportAccessDenied(aCx);
aRv.NoteJSContextException(aCx);
return;
}
if (!mHolder.isSome()) {
aRv.Throw(NS_ERROR_NOT_INITIALIZED);
return;
}
{
JSAutoRealm ar(aCx, scope);
mHolder->Read(xpc::NativeGlobal(scope), aCx, aResult, aRv);
if (aRv.Failed()) {
return;
}
}
if (!aKeepData) {
mHolder.reset();
}
if (!JS_WrapValue(aCx, aResult)) {
aResult.set(JS::UndefinedValue());
aRv.NoteJSContextException(aCx);
}
}
/* static */
JSObject* StructuredCloneBlob::ReadStructuredClone(
JSContext* aCx, JSStructuredCloneReader* aReader,
StructuredCloneHolder* aHolder) {
JS::Rooted<JSObject*> obj(aCx);
{
RefPtr<StructuredCloneBlob> holder = StructuredCloneBlob::Create();
if (!StructuredCloneHolder::ReadCString(aReader, holder->mName)) {
return nullptr;
}
if (!StructuredCloneHolder::ReadCString(aReader, holder->mAnonymizedName)) {
return nullptr;
}
if (!holder->mHolder->ReadStructuredCloneInternal(aCx, aReader, aHolder) ||
!holder->WrapObject(aCx, nullptr, &obj)) {
return nullptr;
}
}
return obj.get();
}
bool StructuredCloneBlob::Holder::ReadStructuredCloneInternal(
JSContext* aCx, JSStructuredCloneReader* aReader,
StructuredCloneHolder* aHolder) {
uint32_t length;
uint32_t version;
if (!JS_ReadUint32Pair(aReader, &length, &version)) {
return false;
}
if (length % 8 != 0) {
return false;
}
uint32_t blobOffset;
uint32_t blobCount;
if (!JS_ReadUint32Pair(aReader, &blobOffset, &blobCount)) {
return false;
}
if (blobCount) {
#ifdef FUZZING
if (blobOffset >= aHolder->BlobImpls().Length()) {
return false;
}
#endif
BlobImpls().AppendElements(&aHolder->BlobImpls()[blobOffset], blobCount);
}
JSStructuredCloneData data(mStructuredCloneScope);
while (length) {
size_t size;
char* buffer = data.AllocateBytes(length, &size);
if (!buffer || !JS_ReadBytes(aReader, buffer, size)) {
return false;
}
length -= size;
}
mBuffer = MakeUnique<JSAutoStructuredCloneBuffer>(
mStructuredCloneScope, &StructuredCloneHolder::sCallbacks, this);
mBuffer->adopt(std::move(data), version, &StructuredCloneHolder::sCallbacks);
return true;
}
bool StructuredCloneBlob::WriteStructuredClone(JSContext* aCx,
JSStructuredCloneWriter* aWriter,
StructuredCloneHolder* aHolder) {
if (mHolder.isNothing()) {
return false;
}
if (!JS_WriteUint32Pair(aWriter, SCTAG_DOM_STRUCTURED_CLONE_HOLDER, 0) ||
!StructuredCloneHolder::WriteCString(aWriter, mName) ||
!StructuredCloneHolder::WriteCString(aWriter, mAnonymizedName)) {
return false;
}
return mHolder->WriteStructuredClone(aCx, aWriter, aHolder);
}
bool StructuredCloneBlob::Holder::WriteStructuredClone(
JSContext* aCx, JSStructuredCloneWriter* aWriter,
StructuredCloneHolder* aHolder) {
auto& data = mBuffer->data();
if (!JS_WriteUint32Pair(aWriter, data.Size(), JS_STRUCTURED_CLONE_VERSION) ||
!JS_WriteUint32Pair(aWriter, aHolder->BlobImpls().Length(),
BlobImpls().Length())) {
return false;
}
aHolder->BlobImpls().AppendElements(BlobImpls());
return data.ForEachDataChunk([&](const char* aData, size_t aSize) {
return JS_WriteBytes(aWriter, aData, aSize);
});
}
bool StructuredCloneBlob::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto,
JS::MutableHandle<JSObject*> aResult) {
return StructuredCloneHolder_Binding::Wrap(aCx, this, aGivenProto, aResult);
}
NS_IMETHODIMP
StructuredCloneBlob::CollectReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData, bool aAnonymize) {
size_t size = MallocSizeOf(this);
if (mHolder.isSome()) {
size += mHolder->SizeOfExcludingThis(MallocSizeOf);
}
aHandleReport->Callback(
""_ns,
nsPrintfCString("explicit/dom/structured-clone-holder/%s",
aAnonymize ? mAnonymizedName.get() : mName.get()),
KIND_HEAP, UNITS_BYTES, size,
"Memory used by StructuredCloneHolder DOM objects."_ns, aData);
return NS_OK;
}
NS_IMPL_ISUPPORTS(StructuredCloneBlob, nsIMemoryReporter)
} // namespace mozilla::dom
|
