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
content / browser / media / key_system_support_impl.cc [blame]
// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/media/key_system_support_impl.h"
#include "base/logging.h"
#include "content/browser/permissions/permission_util.h"
#include "content/browser/web_contents/web_contents_impl.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/render_frame_host.h"
namespace content {
namespace {
// All key systems must have either software or hardware secure capability
// supported.
bool IsValidKeySystemCapabilities(KeySystemCapabilities capabilities) {
for (const auto& entry : capabilities) {
auto& capability = entry.second;
if (!capability.sw_secure_capability.has_value() &&
!capability.hw_secure_capability.has_value()) {
return false;
}
}
return true;
}
} // namespace
KeySystemSupportImpl::KeySystemSupportImpl(RenderFrameHost* render_frame_host)
: DocumentUserData(render_frame_host) {}
KeySystemSupportImpl::~KeySystemSupportImpl() {
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_WIN) || \
BUILDFLAG(IS_FUCHSIA)
render_frame_host()
.GetBrowserContext()
->GetPermissionController()
->UnsubscribeFromPermissionStatusChange(permission_subscription_id_);
#endif
}
void KeySystemSupportImpl::SetGetKeySystemCapabilitiesUpdateCbForTesting(
GetKeySystemCapabilitiesUpdateCB get_support_cb_for_testing) {
get_support_cb_for_testing_ = std::move(get_support_cb_for_testing);
}
void KeySystemSupportImpl::Bind(
mojo::PendingReceiver<media::mojom::KeySystemSupport> receiver) {
key_system_support_receivers_.Add(this, std::move(receiver));
}
void KeySystemSupportImpl::AddObserver(
mojo::PendingRemote<media::mojom::KeySystemSupportObserver> observer) {
DVLOG(3) << __func__;
auto id = observer_remotes_.Add(std::move(observer));
// If `key_system_support_` is already available, notify the new observer
// immediately. All observers will be notified if there are updates later.
if (key_system_capabilities_.has_value()) {
observer_remotes_.Get(id)->OnKeySystemSupportUpdated(
key_system_capabilities_.value());
return;
}
if (!cb_subscription_) {
ObserveKeySystemCapabilities();
}
}
// Initializes permissions values from the
// about://settings/content/protectedContent page. Namely, the default behaviour
// of protected content IDs, and the site specific settings.
void KeySystemSupportImpl::InitializePermissions() {
DCHECK(!are_permissions_initialized_);
// Setup initial permission values.
auto* web_contents = WebContentsImpl::FromRenderFrameHostImpl(
static_cast<RenderFrameHostImpl*>(&render_frame_host()));
is_protected_content_allowed_ =
web_contents->GetRendererPrefs().enable_encrypted_media;
// Initialize permissions for platforms that supports
// PROTECTED_MEDIA_IDENTIFIER.
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_WIN) || \
BUILDFLAG(IS_FUCHSIA)
render_frame_host()
.GetBrowserContext()
->GetPermissionController()
->RequestPermissionFromCurrentDocument(
&render_frame_host(),
PermissionRequestDescription(
blink::PermissionType::PROTECTED_MEDIA_IDENTIFIER,
render_frame_host().HasTransientUserActivation()),
base::BindOnce(&KeySystemSupportImpl::
OnProtectedMediaIdentifierPermissionInitialized,
weak_ptr_factory_.GetWeakPtr()));
#else
are_permissions_initialized_ = true;
SetUpPermissionListeners();
ObserveKeySystemCapabilities();
#endif
}
void KeySystemSupportImpl::SetUpPermissionListeners() {
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_WIN) || \
BUILDFLAG(IS_FUCHSIA)
// Setup permission listeners.
permission_subscription_id_ =
render_frame_host()
.GetBrowserContext()
->GetPermissionController()
->SubscribeToPermissionStatusChange(
blink::PermissionType::PROTECTED_MEDIA_IDENTIFIER,
/*render_process_host=*/nullptr, &render_frame_host(),
PermissionUtil::GetLastCommittedOriginAsURL(&render_frame_host()),
/*should_include_device_status=*/false,
base::BindRepeating(
&KeySystemSupportImpl::
OnProtectedMediaIdentifierPermissionUpdated,
weak_ptr_factory_.GetWeakPtr()));
if (permission_subscription_id_.is_null()) {
LOG(ERROR) << "Could not subscribe to permissions changes for "
"PROTECTED_MEDIA_IDENTIFIER";
// Since we cannot observe changes to PROTECTED_MEDIA_IDENTIFIER, revert
// back to its default value.
is_protected_identifier_allowed_ = false;
}
#endif
GetContentClient()->browser()->RegisterRendererPreferenceWatcher(
render_frame_host().GetBrowserContext(),
preference_watcher_receiver_.BindNewPipeAndPassRemote());
}
void KeySystemSupportImpl::OnProtectedMediaIdentifierPermissionInitialized(
blink::mojom::PermissionStatus status) {
DCHECK(!are_permissions_initialized_);
are_permissions_initialized_ = true;
is_protected_identifier_allowed_ =
status == blink::mojom::PermissionStatus::GRANTED;
SetUpPermissionListeners();
ObserveKeySystemCapabilities();
}
void KeySystemSupportImpl::OnProtectedMediaIdentifierPermissionUpdated(
blink::mojom::PermissionStatus status) {
const bool is_protected_identifier_allowed =
status == blink::mojom::PermissionStatus::GRANTED;
if (is_protected_identifier_allowed == is_protected_identifier_allowed_) {
return;
}
is_protected_identifier_allowed_ = is_protected_identifier_allowed;
ObserveKeySystemCapabilities();
}
void KeySystemSupportImpl::NotifyUpdate(
const blink::RendererPreferences& new_prefs) {
if (is_protected_content_allowed_ == new_prefs.enable_encrypted_media) {
return;
}
is_protected_content_allowed_ = new_prefs.enable_encrypted_media;
ObserveKeySystemCapabilities();
}
bool KeySystemSupportImpl::allow_hw_secure_capability_check() const {
#if BUILDFLAG(IS_WIN)
return is_protected_content_allowed_ && is_protected_identifier_allowed_;
#else
return true;
#endif
}
void KeySystemSupportImpl::ObserveKeySystemCapabilities() {
if (!are_permissions_initialized_) {
// Initialize permissions. Also, we'll continue to observe key system
// capabilities when permissions are initialized.
InitializePermissions();
return;
}
auto result_cb =
base::BindRepeating(&KeySystemSupportImpl::OnKeySystemCapabilitiesUpdated,
weak_ptr_factory_.GetWeakPtr());
if (get_support_cb_for_testing_) {
get_support_cb_for_testing_.Run(allow_hw_secure_capability_check(),
std::move(result_cb));
return;
}
cb_subscription_ =
CdmRegistryImpl::GetInstance()->ObserveKeySystemCapabilities(
allow_hw_secure_capability_check(), std::move(result_cb));
}
void KeySystemSupportImpl::OnKeySystemCapabilitiesUpdated(
KeySystemCapabilities key_system_capabilities) {
DVLOG(3) << __func__;
DCHECK(IsValidKeySystemCapabilities(key_system_capabilities));
if (key_system_capabilities_.has_value() &&
key_system_capabilities_.value() == key_system_capabilities) {
DVLOG(1) << __func__ << ": Updated with the same key system capabilities";
return;
}
// TODO(b/345822323): Filter out non permitted key systems.
key_system_capabilities_ = std::move(key_system_capabilities);
for (auto& observer : observer_remotes_)
observer->OnKeySystemSupportUpdated(key_system_capabilities_.value());
}
DOCUMENT_USER_DATA_KEY_IMPL(KeySystemSupportImpl);
} // namespace content