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
|
// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "third_party/blink/renderer/modules/font_access/font_access.h"
#include <algorithm>
#include "base/containers/contains.h"
#include "base/feature_list.h"
#include "base/numerics/safe_conversions.h"
#include "services/network/public/mojom/permissions_policy/permissions_policy_feature.mojom-blink.h"
#include "third_party/blink/public/common/features.h"
#include "third_party/blink/public/common/font_access/font_enumeration_table.pb.h"
#include "third_party/blink/public/platform/browser_interface_broker_proxy.h"
#include "third_party/blink/public/platform/platform.h"
#include "third_party/blink/renderer/bindings/core/v8/script_promise_resolver.h"
#include "third_party/blink/renderer/bindings/core/v8/v8_throw_dom_exception.h"
#include "third_party/blink/renderer/bindings/modules/v8/v8_query_options.h"
#include "third_party/blink/renderer/core/dom/dom_exception.h"
#include "third_party/blink/renderer/core/execution_context/execution_context_lifecycle_observer.h"
#include "third_party/blink/renderer/core/frame/local_dom_window.h"
#include "third_party/blink/renderer/core/frame/local_frame.h"
#include "third_party/blink/renderer/modules/font_access/font_metadata.h"
#include "third_party/blink/renderer/platform/bindings/script_state.h"
namespace blink {
using mojom::blink::FontEnumerationStatus;
namespace {
const char kFeaturePolicyBlocked[] =
"Access to the feature \"local-fonts\" is disallowed by Permissions Policy";
}
// static
const char FontAccess::kSupplementName[] = "FontAccess";
FontAccess::FontAccess(LocalDOMWindow* window)
: Supplement<LocalDOMWindow>(*window), remote_(window) {}
void FontAccess::Trace(blink::Visitor* visitor) const {
visitor->Trace(remote_);
Supplement<LocalDOMWindow>::Trace(visitor);
}
// static
ScriptPromise<IDLSequence<FontMetadata>> FontAccess::queryLocalFonts(
ScriptState* script_state,
LocalDOMWindow& window,
const QueryOptions* options,
ExceptionState& exception_state) {
DCHECK(ExecutionContext::From(script_state)->IsContextThread());
return From(&window)->QueryLocalFontsImpl(script_state, options,
exception_state);
}
// static
FontAccess* FontAccess::From(LocalDOMWindow* window) {
auto* supplement = Supplement<LocalDOMWindow>::From<FontAccess>(window);
if (!supplement) {
supplement = MakeGarbageCollected<FontAccess>(window);
Supplement<LocalDOMWindow>::ProvideTo(*window, supplement);
}
return supplement;
}
ScriptPromise<IDLSequence<FontMetadata>> FontAccess::QueryLocalFontsImpl(
ScriptState* script_state,
const QueryOptions* options,
ExceptionState& exception_state) {
if (!base::FeatureList::IsEnabled(blink::features::kFontAccess)) {
exception_state.ThrowDOMException(DOMExceptionCode::kNotSupportedError,
"Font Access feature is not supported.");
return ScriptPromise<IDLSequence<FontMetadata>>();
}
if (!script_state->ContextIsValid()) {
exception_state.ThrowDOMException(DOMExceptionCode::kInvalidStateError,
"The execution context is not valid.");
return ScriptPromise<IDLSequence<FontMetadata>>();
}
ExecutionContext* context = ExecutionContext::From(script_state);
if (!context->IsFeatureEnabled(
network::mojom::PermissionsPolicyFeature::kLocalFonts,
ReportOptions::kReportOnFailure)) {
exception_state.ThrowSecurityError(kFeaturePolicyBlocked);
return ScriptPromise<IDLSequence<FontMetadata>>();
}
// Connect to font access manager remote if not bound already.
if (!remote_.is_bound()) {
context->GetBrowserInterfaceBroker().GetInterface(
remote_.BindNewPipeAndPassReceiver(
context->GetTaskRunner(TaskType::kFontLoading)));
remote_.set_disconnect_handler(
WTF::BindOnce(&FontAccess::OnDisconnect, WrapWeakPersistent(this)));
}
DCHECK(remote_.is_bound());
auto* resolver =
MakeGarbageCollected<ScriptPromiseResolver<IDLSequence<FontMetadata>>>(
script_state, exception_state.GetContext());
auto promise = resolver->Promise();
remote_->EnumerateLocalFonts(resolver->WrapCallbackInScriptScope(
WTF::BindOnce(&FontAccess::DidGetEnumerationResponse,
WrapWeakPersistent(this), WrapPersistent(options))));
return promise;
}
void FontAccess::DidGetEnumerationResponse(
const QueryOptions* options,
ScriptPromiseResolver<IDLSequence<FontMetadata>>* resolver,
FontEnumerationStatus status,
base::ReadOnlySharedMemoryRegion region) {
if (!resolver->GetScriptState()->ContextIsValid())
return;
if (RejectPromiseIfNecessary(status, resolver))
return;
// Return an empty font list if user has denied the permission request.
if (status == FontEnumerationStatus::kPermissionDenied) {
HeapVector<Member<FontMetadata>> entries;
resolver->Resolve(std::move(entries));
return;
}
// Font data exists; process and fill in the data.
base::ReadOnlySharedMemoryMapping mapping = region.Map();
FontEnumerationTable table;
if (mapping.size() > INT_MAX) {
// Cannot deserialize without overflow.
resolver->Reject(V8ThrowDOMException::CreateOrDie(
resolver->GetScriptState()->GetIsolate(), DOMExceptionCode::kDataError,
"Font data exceeds memory limit."));
return;
}
// Used to compare with data coming from the browser to avoid conversions.
const bool hasPostscriptNameFilter = options->hasPostscriptNames();
std::set<std::string> selection_utf8;
if (hasPostscriptNameFilter) {
for (const String& postscriptName : options->postscriptNames()) {
// While postscript names are encoded in a subset of ASCII, we convert the
// input into UTF8. This will still allow exact matches to occur.
selection_utf8.insert(postscriptName.Utf8());
}
}
HeapVector<Member<FontMetadata>> entries;
base::span<const uint8_t> mapped_mem(mapping);
table.ParseFromArray(mapped_mem.data(),
base::checked_cast<int>(mapped_mem.size()));
for (const auto& element : table.fonts()) {
// If the optional postscript name filter is set in QueryOptions,
// only allow items that match.
if (hasPostscriptNameFilter &&
!base::Contains(selection_utf8, element.postscript_name().c_str())) {
continue;
}
auto entry = FontEnumerationEntry{
.postscript_name = String::FromUTF8(element.postscript_name()),
.full_name = String::FromUTF8(element.full_name()),
.family = String::FromUTF8(element.family()),
.style = String::FromUTF8(element.style()),
};
entries.push_back(FontMetadata::Create(std::move(entry)));
}
resolver->Resolve(std::move(entries));
}
bool FontAccess::RejectPromiseIfNecessary(const FontEnumerationStatus& status,
ScriptPromiseResolverBase* resolver) {
switch (status) {
case FontEnumerationStatus::kOk:
case FontEnumerationStatus::kPermissionDenied:
break;
case FontEnumerationStatus::kUnimplemented:
resolver->Reject(V8ThrowDOMException::CreateOrDie(
resolver->GetScriptState()->GetIsolate(),
DOMExceptionCode::kNotSupportedError,
"Not yet supported on this platform."));
return true;
case FontEnumerationStatus::kNeedsUserActivation:
resolver->Reject(V8ThrowDOMException::CreateOrDie(
resolver->GetScriptState()->GetIsolate(),
DOMExceptionCode::kSecurityError, "User activation is required."));
return true;
case FontEnumerationStatus::kNotVisible:
resolver->Reject(V8ThrowDOMException::CreateOrDie(
resolver->GetScriptState()->GetIsolate(),
DOMExceptionCode::kSecurityError, "Page needs to be visible."));
return true;
case FontEnumerationStatus::kUnexpectedError:
default:
resolver->Reject(V8ThrowDOMException::CreateOrDie(
resolver->GetScriptState()->GetIsolate(),
DOMExceptionCode::kUnknownError, "An unexpected error occured."));
return true;
}
return false;
}
void FontAccess::OnDisconnect() {
remote_.reset();
}
} // namespace blink
|
