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
|
<!DOCTYPE html>
<html>
<head>
<title>Test Encrypted Media Extensions - Protection Query</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
<script type="text/javascript" src="manifest.js"></script>
<script type="text/javascript" src="eme.js"></script>
</head>
<body>
<pre id="test">
<script class="testbody" type="text/javascript">
// Tests in this file check that output protection queries are performed and
// handled correctly. This is done by using a special clear key key system that
// emits key status to track protection status.
// Special key system used for these tests.
const kClearKeyWithProtectionQuery =
"org.mozilla.clearkey_with_protection_query";
const kTestFile = "bipbop-cenc-video-10s.mp4";
const kTestMimeType = 'video/mp4; codecs="avc1.4d4015"';
const kTestKeyId = "7e571d037e571d037e571d037e571d11"; // Hex representation
const kTestKey = "7e5733337e5733337e5733337e573311";
// This is the special key-id used by the mozilla clearkey CDM to signal
// protection query status. As hex it is "6f75747075742d70726f74656374696f6e",
// the hex translates to ascii "output-protection".
const kProtectionQueryKeyIdString = "output-protection";
// Options for requestMediaKeySystemAccess
const kKeySystemOptions = [
{
initDataTypes: ["cenc"],
videoCapabilities: [{ contentType: kTestMimeType }],
},
];
// Helper to setup EME on `video`.
// @param video the HTMLMediaElement to configure EME on.
// @returns a media key session for the video. Callers can use this to
// configure the `onkeystatuseschange` event handler for each test. Callers
// *should not* configure other aspects of the session as this helper already
// does so.
async function setupEme(video) {
// Start setting up EME.
let access = await navigator.requestMediaKeySystemAccess(
kClearKeyWithProtectionQuery,
kKeySystemOptions
);
let mediaKeys = await access.createMediaKeys();
await video.setMediaKeys(mediaKeys);
let session = video.mediaKeys.createSession();
video.onencrypted = async encryptedEvent => {
session.onmessage = messageEvent => {
// Handle license messages. Hard code the license because we always test
// with the same file and we know what the license should be.
const license = {
keys: [
{
kty: "oct",
kid: HexToBase64(kTestKeyId),
k: HexToBase64(kTestKey),
},
],
type: "temporary",
};
const encodedLicense = new TextEncoder().encode(JSON.stringify(license));
session.update(encodedLicense);
};
session.generateRequest(
encryptedEvent.initDataType,
encryptedEvent.initData
);
};
return session;
}
// Helper to setup MSE media on `video`.
// @param video the HTMLMediaElement to configure MSE on.
async function setupMse(video) {
const mediaSource = new MediaSource();
video.src = URL.createObjectURL(mediaSource);
await once(mediaSource, "sourceopen");
const sourceBuffer = mediaSource.addSourceBuffer("video/mp4");
let fetchResponse = await fetch(kTestFile);
sourceBuffer.appendBuffer(await fetchResponse.arrayBuffer());
await once(sourceBuffer, "updateend");
mediaSource.endOfStream();
await once(mediaSource, "sourceended");
}
// Helper to create a video element and append it to the page.
function createAndAppendVideo() {
const video = document.createElement("video");
video.id = "video";
// Loop in case tests run slowly, we want video to keep playing until we
// get expected events.
video.loop = true;
document.body.appendChild(video);
return video;
}
// Helper to remove a video from the page.
function removeVideo() {
let video = document.getElementById("video");
CleanUpMedia(video);
}
// Helper to get the status for the kProtectionQueryKeyIdString key id. A
// session can (and will) have other keys with their own status, but we want
// to check this special key to find the protection query status.
function getKeyStatusForProtectionKeyId(session) {
for (let [keyId, status] of session.keyStatuses) {
if (ArrayBufferToString(keyId) == kProtectionQueryKeyIdString) {
return status;
}
}
return null;
}
async function getDisplayMedia() {
SpecialPowers.wrap(document).notifyUserGestureActivation();
return navigator.mediaDevices.getDisplayMedia();
}
// Tests playing encrypted media, starting a screen capture during playback,
// then stopping the capture while playback continues.
async function testProtectionQueryWithCaptureDuringVideo() {
let video = createAndAppendVideo();
// Configure the video and start it playing. KeyId should be usable (not restricted).
let session = await setupEme(video);
let keyStatusChangedPromise1 = new Promise(
resolve =>
(session.onkeystatuseschange = () => {
// We may get status changes prior to kProtectionQueryKeyIdString changing,
// ensure we wait for the first kProtectionQueryKeyIdString change.
if (getKeyStatusForProtectionKeyId(session)) {
resolve();
}
})
);
await setupMse(video);
await Promise.all([video.play(), keyStatusChangedPromise1]);
is(
getKeyStatusForProtectionKeyId(session),
"usable",
"Should be usable as capture hasn't started"
);
let keyStatusChangedPromise2 = new Promise(
resolve => (session.onkeystatuseschange = resolve)
);
let [displayMediaStream] = await Promise.all([
// Start a screen capture, this should restrict output.
getDisplayMedia(),
keyStatusChangedPromise2,
]);
is(
getKeyStatusForProtectionKeyId(session),
"output-restricted",
"Should be output-restricted as capture is happening"
);
// Stop the screen capture, output should be usable again.
let keyStatusChangedPromise3 = new Promise(
resolve => (session.onkeystatuseschange = resolve)
);
displayMediaStream.getTracks().forEach(track => track.stop());
displayMediaStream = null;
await keyStatusChangedPromise3;
is(
getKeyStatusForProtectionKeyId(session),
"usable",
"Should be usable as capture has stopped"
);
removeVideo();
}
// Tests starting a screen capture, then starting encrypted playback, then
// stopping the screen capture while encrypted playback continues.
async function testProtectionQueryWithCaptureStartingBeforeVideo() {
// Start capture before setting up video.
let displayMediaStream = await getDisplayMedia();
let video = createAndAppendVideo();
// Configure the video and start it playing. KeyId should be restricted already.
let session = await setupEme(video);
let keyStatusChangedPromise1 = new Promise(
resolve =>
(session.onkeystatuseschange = () => {
// We may get status changes prior to kProtectionQueryKeyIdString changing,
// ensure we wait for the first kProtectionQueryKeyIdString change. In
// rare cases the first protection status can be "usable" due to racing
// between playback and the machinery that detects WebRTC capture. To
// avoid this, wait for the first 'output-restricted' notification,
// which will either be the first event, or will quickly follow 'usable'.
if (getKeyStatusForProtectionKeyId(session) == "output-restricted") {
resolve();
}
})
);
await setupMse(video);
await Promise.all([video.play(), keyStatusChangedPromise1]);
is(
getKeyStatusForProtectionKeyId(session),
"output-restricted",
"Should be restricted as capture is happening"
);
// Stop the screen capture, output should be usable again.
let keyStatusChangedPromise2 = new Promise(
resolve => (session.onkeystatuseschange = resolve)
);
displayMediaStream.getTracks().forEach(track => track.stop());
displayMediaStream = null;
await keyStatusChangedPromise2;
is(
getKeyStatusForProtectionKeyId(session),
"usable",
"Should be usable as capture has stopped"
);
removeVideo();
}
add_task(async function setupEnvironment() {
await SpecialPowers.pushPrefEnv({
set: [
// Need test key systems for test key system.
["media.clearkey.test-key-systems.enabled", true],
// Need relaxed navigator permissions for getDisplayMedia.
["media.navigator.permission.disabled", true],
],
});
});
add_task(testProtectionQueryWithCaptureDuringVideo);
add_task(testProtectionQueryWithCaptureStartingBeforeVideo);
</script>
</pre>
</body>
</html>
|
