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index.html
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<!DOCTYPE html><html lang="en" dir="ltr"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><meta name="generator" content="ReSpec 24.37.0"><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><style>/* --- EXAMPLES --- */
span.example-title {
text-transform: none;
}
aside.example, div.example, div.illegal-example {
padding: 0.5em;
margin: 1em 0;
position: relative;
clear: both;
}
div.illegal-example { color: red }
div.illegal-example p { color: black }
aside.example, div.example {
padding: .5em;
border-left-width: .5em;
border-left-style: solid;
border-color: #e0cb52;
background: #fcfaee;
}
aside.example div.example {
border-left-width: .1em;
border-color: #999;
background: #fff;
}
aside.example div.example span.example-title {
color: #999;
}
</style><style>/* --- ISSUES/NOTES --- */
.issue-label {
text-transform: initial;
}
.warning > p:first-child { margin-top: 0 }
.warning {
padding: .5em;
border-left-width: .5em;
border-left-style: solid;
}
span.warning { padding: .1em .5em .15em; }
.issue.closed span.issue-number {
text-decoration: line-through;
}
.warning {
border-color: #f11;
border-width: .2em;
border-style: solid;
background: #fbe9e9;
}
.warning-title:before{
content: "⚠"; /*U+26A0 WARNING SIGN*/
font-size: 1.3em;
float: left;
padding-right: .3em;
margin-top: -0.3em;
}
li.task-list-item {
list-style: none;
}
input.task-list-item-checkbox {
margin: 0 0.35em 0.25em -1.6em;
vertical-align: middle;
}
.issue a.respec-gh-label {
padding: 5px;
margin: 0 2px 0 2px;
font-size: 10px;
text-transform: none;
text-decoration: none;
font-weight: bold;
border-radius: 4px;
position: relative;
bottom: 2px;
border: none;
display: inline-block;
}
.issue a.respec-label-dark {
color: #fff;
background-color: #000;
}
.issue a.respec-label-light {
color: #000;
background-color: #fff;
}
</style><style>/* --- WEB IDL --- */
pre.idl {
padding: 1em;
position: relative;
}
@media print {
pre.idl {
white-space: pre-wrap;
}
}
pre.idl::before {
content: "WebIDL";
display: block;
width: 150px;
background: #90b8de;
color: #fff;
font-family: sans-serif;
font-weight: bold;
margin: -1em 0 1em -1em;
height: 28px;
line-height: 28px;
}
.idlID {
font-weight: bold;
color: #005a9c;
}
.idlType {
color: #005a9c;
}
.idlName {
color: #ff4500;
}
.idlName a {
color: #ff4500;
border-bottom: 1px dotted #ff4500;
text-decoration: none;
}
a.idlEnumItem {
color: #000;
border-bottom: 1px dotted #ccc;
text-decoration: none;
}
.idlSuperclass {
font-style: italic;
color: #005a9c;
}
/*.idlParam*/
.idlParamName,
.idlDefaultValue {
font-style: italic;
}
.extAttr {
color: #666;
}
/*.idlSectionComment*/
.idlSectionComment {
color: gray;
}
.idlIncludes a {
font-weight: bold;
}
.respec-button-copy-paste:focus {
text-decoration: none;
border-color: #51a7e8;
outline: none;
box-shadow: 0 0 5px rgba(81, 167, 232, 0.5);
}
.respec-button-copy-paste:focus:hover,
.respec-button-copy-paste.selected:focus {
border-color: #51a7e8;
}
.respec-button-copy-paste:hover,
.respec-button-copy-paste:active,
.respec-button-copy-paste.zeroclipboard-is-hover,
.respec-button-copy-paste.zeroclipboard-is-active {
text-decoration: none;
background-color: #ddd;
background-image: linear-gradient(#eee, #ddd);
border-color: #ccc;
}
.respec-button-copy-paste:active,
.respec-button-copy-paste.selected,
.respec-button-copy-paste.zeroclipboard-is-active {
background-color: #dcdcdc;
background-image: none;
border-color: #b5b5b5;
box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.15)
}
.respec-button-copy-paste.selected:hover {
background-color: #cfcfcf;
}
.respec-button-copy-paste:disabled,
.respec-button-copy-paste:disabled:hover,
.respec-button-copy-paste.disabled,
.respec-button-copy-paste.disabled:hover {
color: rgba(102, 102, 102, 0.5);
cursor: default;
background-color: rgba(229, 229, 229, 0.5);
background-image: none;
border-color: rgba(197, 197, 197, 0.5);
box-shadow: none;
}
@media print {
.respec-button-copy-paste {
visibility: hidden;
}
}
</style>
<title>Encrypted Media Extensions</title>
<style id="respec-mainstyle">/*****************************************************************
* ReSpec 3 CSS
* Robin Berjon - http://berjon.com/
*****************************************************************/
@keyframes pop {
0% {
transform: scale(1, 1);
}
25% {
transform: scale(1.25, 1.25);
opacity: 0.75;
}
100% {
transform: scale(1, 1);
}
}
/* Override code highlighter background */
.hljs {
background: transparent !important;
}
/* --- INLINES --- */
h1 abbr,
h2 abbr,
h3 abbr,
h4 abbr,
h5 abbr,
h6 abbr,
a abbr {
border: none;
}
dfn {
font-weight: bold;
}
a.internalDFN {
color: inherit;
border-bottom: 1px solid #99c;
text-decoration: none;
}
a.externalDFN {
color: inherit;
border-bottom: 1px dotted #ccc;
text-decoration: none;
}
a.bibref {
text-decoration: none;
}
.respec-offending-element:target {
animation: pop 0.25s ease-in-out 0s 1;
}
.respec-offending-element,
a[href].respec-offending-element {
text-decoration: red wavy underline;
}
@supports not (text-decoration: red wavy underline) {
.respec-offending-element:not(pre) {
display: inline-block;
}
.respec-offending-element {
/* Red squiggly line */
background: url(data:image/gif;base64,R0lGODdhBAADAPEAANv///8AAP///wAAACwAAAAABAADAEACBZQjmIAFADs=)
bottom repeat-x;
}
}
#references :target {
background: #eaf3ff;
animation: pop 0.4s ease-in-out 0s 1;
}
cite .bibref {
font-style: normal;
}
code {
color: #c83500;
}
th code {
color: inherit;
}
a[href].orcid {
padding-left: 4px;
padding-right: 4px;
}
a[href].orcid > svg {
margin-bottom: -2px;
}
/* --- TOC --- */
.toc a,
.tof a {
text-decoration: none;
}
a .secno,
a .figno {
color: #000;
}
ul.tof,
ol.tof {
list-style: none outside none;
}
.caption {
margin-top: 0.5em;
font-style: italic;
}
/* --- TABLE --- */
table.simple {
border-spacing: 0;
border-collapse: collapse;
border-bottom: 3px solid #005a9c;
}
.simple th {
background: #005a9c;
color: #fff;
padding: 3px 5px;
text-align: left;
}
.simple th a {
color: #fff;
padding: 3px 5px;
text-align: left;
}
.simple th[scope="row"] {
background: inherit;
color: inherit;
border-top: 1px solid #ddd;
}
.simple td {
padding: 3px 10px;
border-top: 1px solid #ddd;
}
.simple tr:nth-child(even) {
background: #f0f6ff;
}
/* --- DL --- */
.section dd > p:first-child {
margin-top: 0;
}
.section dd > p:last-child {
margin-bottom: 0;
}
.section dd {
margin-bottom: 1em;
}
.section dl.attrs dd,
.section dl.eldef dd {
margin-bottom: 0;
}
#issue-summary > ul,
.respec-dfn-list {
column-count: 2;
}
#issue-summary li,
.respec-dfn-list li {
list-style: none;
}
details.respec-tests-details {
margin-left: 1em;
display: inline-block;
vertical-align: top;
}
details.respec-tests-details > * {
padding-right: 2em;
}
details.respec-tests-details[open] {
z-index: 999999;
position: absolute;
border: thin solid #cad3e2;
border-radius: 0.3em;
background-color: white;
padding-bottom: 0.5em;
}
details.respec-tests-details[open] > summary {
border-bottom: thin solid #cad3e2;
padding-left: 1em;
margin-bottom: 1em;
line-height: 2em;
}
details.respec-tests-details > ul {
width: 100%;
margin-top: -0.3em;
}
details.respec-tests-details > li {
padding-left: 1em;
}
a[href].self-link:hover {
opacity: 1;
text-decoration: none;
background-color: transparent;
}
h2,
h3,
h4,
h5,
h6 {
position: relative;
}
aside.example .marker > a.self-link {
color: inherit;
}
h2 > a.self-link,
h3 > a.self-link,
h4 > a.self-link,
h5 > a.self-link,
h6 > a.self-link {
border: none;
color: inherit;
font-size: 83%;
height: 2em;
left: -1.6em;
opacity: 0.5;
position: absolute;
text-align: center;
text-decoration: none;
top: 0;
transition: opacity 0.2s;
width: 2em;
}
h2 > a.self-link::before,
h3 > a.self-link::before,
h4 > a.self-link::before,
h5 > a.self-link::before,
h6 > a.self-link::before {
content: "§";
display: block;
}
@media (max-width: 767px) {
dd {
margin-left: 0;
}
/* Don't position self-link in headings off-screen */
h2 > a.self-link,
h3 > a.self-link,
h4 > a.self-link,
h5 > a.self-link,
h6 > a.self-link {
left: auto;
top: auto;
}
}
@media print {
.removeOnSave {
display: none;
}
}
</style>
<link rel="stylesheet" href="eme.css">
<meta name="description" content="This proposal extends [HTML] providing APIs to control playback of encrypted content."><link rel="canonical" href="https://www.w3.org/TR/encrypted-media/"><style>/*
github.com style (c) Vasily Polovnyov <[email protected]>
*/
.hljs {
display: block;
overflow-x: auto;
padding: 0.5em;
color: #333;
background: #f8f8f8;
}
.hljs-comment,
.hljs-quote {
color: #998;
font-style: italic;
}
.hljs-keyword,
.hljs-selector-tag,
.hljs-subst {
color: #333;
font-weight: bold;
}
.hljs-number,
.hljs-literal,
.hljs-variable,
.hljs-template-variable,
.hljs-tag .hljs-attr {
color: #008080;
}
.hljs-string,
.hljs-doctag {
color: #d14;
}
.hljs-title,
.hljs-section,
.hljs-selector-id {
color: #900;
font-weight: bold;
}
.hljs-subst {
font-weight: normal;
}
.hljs-type,
.hljs-class .hljs-title {
color: #458;
font-weight: bold;
}
.hljs-tag,
.hljs-name,
.hljs-attribute {
color: #000080;
font-weight: normal;
}
.hljs-regexp,
.hljs-link {
color: #009926;
}
.hljs-symbol,
.hljs-bullet {
color: #990073;
}
.hljs-built_in,
.hljs-builtin-name {
color: #0086b3;
}
.hljs-meta {
color: #999;
font-weight: bold;
}
.hljs-deletion {
background: #fdd;
}
.hljs-addition {
background: #dfd;
}
.hljs-emphasis {
font-style: italic;
}
.hljs-strong {
font-weight: bold;
}
</style><style>var {
position: relative;
cursor: pointer;
}
var[data-type]::before,
var[data-type]::after {
position: absolute;
left: 50%;
top: -6px;
opacity: 0;
transition: opacity 0.4s;
pointer-events: none;
}
/* the triangle or arrow or caret or whatever */
var[data-type]::before {
content: "";
transform: translateX(-50%);
border-width: 4px 6px 0 6px;
border-style: solid;
border-color: transparent;
border-top-color: #000;
}
/* actual text */
var[data-type]::after {
content: attr(data-type);
transform: translateX(-50%) translateY(-100%);
background: #000;
text-align: center;
/* additional styling */
font-family: "Dank Mono", "Fira Code", monospace;
font-style: normal;
padding: 6px;
border-radius: 3px;
color: #daca88;
text-indent: 0;
font-weight: normal;
}
var[data-type]:hover::after,
var[data-type]:hover::before {
opacity: 1;
}
</style><script id="initialUserConfig" type="application/json">{
"specStatus": "ED",
"implementationReportURI": "https://w3c.github.io/test-results/encrypted-media/all.html",
"shortName": "encrypted-media",
"license": "w3c-software-doc",
"useExperimentalStyles": true,
"edDraftURI": "https://w3c.github.io/encrypted-media/",
"editors": [
{
"name": "Joey Parrish",
"w3cid": "105371",
"company": "Google Inc.",
"companyURL": "https://www.google.com/"
},
{
"name": "Greg Freedman",
"company": "Netflix Inc.",
"companyURL": "https://www.netflix.com/"
}
],
"formerEditors": [
{
"name": "Mark Watson",
"note": "Until September 2019",
"w3cid": "46379",
"company": "Netflix Inc.",
"companyURL": "https://www.netflix.com/"
},
{
"name": "David Dorwin",
"note": "Until September 2017",
"w3cid": "52505",
"company": "Google Inc.",
"companyURL": "https://www.google.com/"
},
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<body data-cite="WebIDL HTML" class="h-entry"><div class="head">
<a class="logo" href="https://www.w3.org/"><img alt="W3C" width="72" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C"></a> <h1 id="title" class="title p-name">Encrypted Media Extensions</h1>
<h2>
W3C Editor's Draft
<time class="dt-published" datetime="2019-12-13">13 December 2019</time>
</h2>
<dl>
<dt>This version:</dt><dd>
<a class="u-url" href="https://w3c.github.io/encrypted-media/">https://w3c.github.io/encrypted-media/</a>
</dd><dt>Latest published version:</dt><dd>
<a href="https://www.w3.org/TR/encrypted-media/">https://www.w3.org/TR/encrypted-media/</a>
</dd>
<dt>Latest editor's draft:</dt><dd><a href="https://w3c.github.io/encrypted-media/">https://w3c.github.io/encrypted-media/</a></dd>
<dt>Implementation report:</dt><dd>
<a href="https://w3c.github.io/test-results/encrypted-media/all.html">https://w3c.github.io/test-results/encrypted-media/all.html</a>
</dd>
<dt>Editors:</dt>
<dd class="p-author h-card vcard" data-editor-id="105371"><span class="p-name fn">Joey Parrish</span>
(<a class="p-org org h-org h-card" href="https://www.google.com/">Google Inc.</a>)
</dd><dd class="p-author h-card vcard"><span class="p-name fn">Greg Freedman</span>
(<a class="p-org org h-org h-card" href="https://www.netflix.com/">Netflix Inc.</a>)
</dd>
<dt>
Former editors:
</dt><dd class="p-author h-card vcard" data-editor-id="46379"><span class="p-name fn">Mark Watson</span>
(<a class="p-org org h-org h-card" href="https://www.netflix.com/">Netflix Inc.</a>)
(Until September 2019)</dd><dd class="p-author h-card vcard" data-editor-id="52505"><span class="p-name fn">David Dorwin</span>
(<a class="p-org org h-org h-card" href="https://www.google.com/">Google Inc.</a>)
(Until September 2017)</dd><dd class="p-author h-card vcard" data-editor-id="60176"><span class="p-name fn">Jerry Smith</span>
(<a class="p-org org h-org h-card" href="https://www.microsoft.com/">Microsoft Corporation</a>)
(Until September 2017)</dd><dd class="p-author h-card vcard" data-editor-id="42763"><span class="p-name fn">Adrian Bateman</span>
(<a class="p-org org h-org h-card" href="https://www.microsoft.com/">Microsoft Corporation</a>)
(Until May 2014)</dd>
<dt>Repository:</dt><dd>
<a href="https://github.com/w3c/encrypted-media/">We are on GitHub.</a>
</dd><dd>
<a href="https://github.com/w3c/encrypted-media/issues">File a bug.</a>
</dd><dd>
<a href="https://github.com/w3c/encrypted-media/commits/gh-pages/encrypted-media-respec.html">Commit history.</a>
</dd>
</dl>
<p class="copyright">
<a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a>
©
2019
<a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>,
<a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>,
<a href="https://ev.buaa.edu.cn/">Beihang</a>).
W3C <a href="https://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
<a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a rel="license" href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document">permissive document license</a> rules
apply.
</p>
<hr title="Separator for header">
</div>
<section id="abstract" class="introductory"><h2>Abstract</h2>
<p>This proposal extends <code><a href="https://www.w3.org/TR/html51/semantics-embedded-content.html#htmlmediaelement-htmlmediaelement">HTMLMediaElement</a></code> [<cite><a class="bibref" href="#bib-html" title="HTML Standard" data-link-type="biblio">HTML</a></cite>] providing APIs to control playback of encrypted content.</p>
<p>The API supports use cases ranging from simple clear key decryption to high value video (given an appropriate user agent implementation).
License/key exchange is controlled by the application, facilitating the development of robust playback applications supporting a range of content decryption and protection technologies.</p>
<p>This specification does not define a content protection or Digital Rights Management system. Rather, it defines a common API that may be used to discover, select and interact with
such systems as well as with simpler content encryption systems. Implementation of Digital Rights Management is not required for compliance with this specification: only the
Clear Key system is required to be implemented as a common baseline.</p>
<p>The common API supports a simple set of content encryption capabilities, leaving application functions such as authentication and authorization to page authors. This is achieved by
requiring content protection system-specific messaging to be mediated by the page rather than assuming out-of-band communication between the encryption system and a license
or other server.</p>
</section>
<section id="sotd" class="introductory"><h2>Status of This Document</h2><p><em>This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current <abbr title="World Wide Web Consortium">W3C</abbr> publications and the latest revision of this technical report can be found in the <a href="https://www.w3.org/TR/"><abbr title="World Wide Web Consortium">W3C</abbr> technical reports index</a> at https://www.w3.org/TR/.</em></p>
<p>
This document was published by the <a href="https://www.w3.org/media-wg/">Media Working Group</a> as an
Editor's Draft.
</p><p>
Comments regarding this document are welcome.
Please send them to
<a href="mailto:[email protected]">[email protected]</a>
(<a href="https://lists.w3.org/Archives/Public/public-media-wg/">archives</a>).
</p><p>
Please see the Working Group's
<a href="https://w3c.github.io/test-results/encrypted-media/all.html">implementation report</a>.
</p><p>
Publication as an Editor's Draft does not imply endorsement by the
<abbr title="World Wide Web Consortium">W3C</abbr> Membership. This is a draft document and may be updated, replaced or
obsoleted by other documents at any time. It is inappropriate to cite this
document as other than work in progress.
</p><p>
This document was produced by a group
operating under the
<a href="https://www.w3.org/Consortium/Patent-Policy/"><abbr title="World Wide Web Consortium">W3C</abbr> Patent Policy</a>.
<abbr title="World Wide Web Consortium">W3C</abbr> maintains a
<a rel="disclosure" href="https://www.w3.org/2004/01/pp-impl/115198/status">public list of any patent disclosures</a>
made in connection with the deliverables of
the group; that page also includes
instructions for disclosing a patent. An individual who has actual
knowledge of a patent which the individual believes contains
<a href="https://www.w3.org/Consortium/Patent-Policy/#def-essential">Essential Claim(s)</a>
must disclose the information in accordance with
<a href="https://www.w3.org/Consortium/Patent-Policy/#sec-Disclosure">section 6 of the <abbr title="World Wide Web Consortium">W3C</abbr> Patent Policy</a>.
</p><p>
This document is governed by the
<a id="w3c_process_revision" href="https://www.w3.org/2019/Process-20190301/">1 March 2019 <abbr title="World Wide Web Consortium">W3C</abbr> Process Document</a>.
</p></section><nav id="toc"><h2 class="introductory" id="table-of-contents">Table of Contents</h2><ol class="toc"><li class="tocline"><a class="tocxref" href="#introduction"><bdi class="secno">1. </bdi>Introduction</a></li><li class="tocline"><a class="tocxref" href="#definitions"><bdi class="secno">2. </bdi>Definitions</a></li><li class="tocline"><a class="tocxref" href="#obtaining-access-to-key-systems"><bdi class="secno">3. </bdi>Obtaining Access to Key Systems</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#feature-policy-integration"><bdi class="secno">3.1 </bdi>Feature Policy Integration</a></li><li class="tocline"><a class="tocxref" href="#navigator-extension-requestmediakeysystemaccess"><bdi class="secno">3.2 </bdi><span data-dfn-type="dfn" data-idl="interface" data-title="Navigator" data-dfn-for=""><code>Navigator</code></span> Extension: <code>requestMediaKeySystemAccess()</code></a><ol class="toc"><li class="tocline"><a class="tocxref" href="#algorithms"><bdi class="secno">3.2.1 </bdi>Algorithms</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#get-supported-configuration"><bdi class="secno">3.2.1.1 </bdi>Get Supported Configuration</a></li><li class="tocline"><a class="tocxref" href="#get-supported-configuration-and-consent"><bdi class="secno">3.2.1.2 </bdi>Get Supported Configuration and Consent</a></li><li class="tocline"><a class="tocxref" href="#get-supported-capabilities-for-audio-video-type"><bdi class="secno">3.2.1.3 </bdi>Get Supported Capabilities for Audio/Video Type</a></li><li class="tocline"><a class="tocxref" href="#get-consent-status"><bdi class="secno">3.2.1.4 </bdi>Get Consent Status</a></li></ol></li></ol></li><li class="tocline"><a class="tocxref" href="#mediakeysystemconfiguration-dictionary"><bdi class="secno">3.3 </bdi><span class="formerLink" data-link-type="idl"><code>MediaKeySystemConfiguration</code></span> dictionary</a></li><li class="tocline"><a class="tocxref" href="#mediakeysystemmediacapability-dictionary"><bdi class="secno">3.4 </bdi><span data-dfn-type="dictionary" data-export="" data-idl="dictionary" data-title="MediaKeySystemMediaCapability" data-dfn-for=""><code>MediaKeySystemMediaCapability</code></span> dictionary</a></li></ol></li><li class="tocline"><a class="tocxref" href="#mediakeysystemaccess-interface"><bdi class="secno">4. </bdi><span data-dfn-type="interface" data-export="" data-idl="interface" data-title="MediaKeySystemAccess" data-dfn-for=""><code>MediaKeySystemAccess</code></span> Interface</a></li><li class="tocline"><a class="tocxref" href="#mediakeys-interface"><bdi class="secno">5. </bdi><span data-dfn-type="interface" data-export="" data-idl="interface" data-title="MediaKeys" data-dfn-for=""><code>MediaKeys</code></span> Interface</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#algorithms-0"><bdi class="secno">5.1 </bdi>Algorithms</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#is-persistent-session-type"><bdi class="secno">5.1.1 </bdi>Is persistent session type?</a></li><li class="tocline"><a class="tocxref" href="#cdm-unavailable"><bdi class="secno">5.1.2 </bdi>CDM Unavailable</a></li></ol></li><li class="tocline"><a class="tocxref" href="#media-keys-storage"><bdi class="secno">5.2 </bdi>Storage and Persistence</a></li></ol></li><li class="tocline"><a class="tocxref" href="#mediakeysession-interface"><bdi class="secno">6. </bdi><span data-dfn-type="interface" data-export="" data-idl="interface" data-title="MediaKeySession" data-dfn-for=""><code>MediaKeySession</code></span> Interface</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#mediakeystatusmap-interface"><bdi class="secno">6.1 </bdi><span data-dfn-type="interface" data-export="" data-idl="interface" data-title="MediaKeyStatusMap" data-dfn-for=""><code>MediaKeyStatusMap</code></span> Interface</a></li><li class="tocline"><a class="tocxref" href="#mediakeymessageevent"><bdi class="secno">6.2 </bdi><span class="formerLink" data-link-type="idl"><code>MediaKeyMessageEvent</code></span></a><ol class="toc"><li class="tocline"><a class="tocxref" href="#mediakeymessageeventinit"><bdi class="secno">6.2.1 </bdi><span data-dfn-type="dictionary" data-export="" data-idl="dictionary" data-title="MediaKeyMessageEventInit" data-dfn-for=""><code>MediaKeyMessageEventInit</code></span></a></li></ol></li><li class="tocline"><a class="tocxref" href="#mediakeysession-events"><bdi class="secno">6.3 </bdi>Event Summary</a></li><li class="tocline"><a class="tocxref" href="#mediakeysession-algorithms"><bdi class="secno">6.4 </bdi>Algorithms</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#queue-message"><bdi class="secno">6.4.1 </bdi>Queue a "message" Event</a></li><li class="tocline"><a class="tocxref" href="#update-key-statuses"><bdi class="secno">6.4.2 </bdi>Update Key Statuses</a></li><li class="tocline"><a class="tocxref" href="#update-expiration"><bdi class="secno">6.4.3 </bdi>Update Expiration</a></li><li class="tocline"><a class="tocxref" href="#session-closed"><bdi class="secno">6.4.4 </bdi>Session Closed</a></li><li class="tocline"><a class="tocxref" href="#media-key-session-destroyed"><bdi class="secno">6.4.5 </bdi>MediaKeySession Destroyed</a></li><li class="tocline"><a class="tocxref" href="#monitor-cdm"><bdi class="secno">6.4.6 </bdi>Monitor for CDM State Changes</a></li></ol></li><li class="tocline"><a class="tocxref" href="#exceptions"><bdi class="secno">6.5 </bdi>Exceptions</a></li><li class="tocline"><a class="tocxref" href="#session-storage"><bdi class="secno">6.6 </bdi>Session Storage and Persistence</a></li></ol></li><li class="tocline"><a class="tocxref" href="#htmlmediaelement-extensions"><bdi class="secno">7. </bdi><span data-dfn-type="dfn" data-idl="interface" data-title="HTMLMediaElement" data-dfn-for=""><code>HTMLMediaElement</code></span> Extensions</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#mediaencryptedevent"><bdi class="secno">7.1 </bdi><span class="formerLink" data-link-type="idl"><code>MediaEncryptedEvent</code></span></a><ol class="toc"><li class="tocline"><a class="tocxref" href="#mediaencryptedeventinit"><bdi class="secno">7.1.1 </bdi><span data-dfn-type="dictionary" data-export="" data-idl="dictionary" data-title="MediaEncryptedEventInit" data-dfn-for=""><code>MediaEncryptedEventInit</code></span></a></li></ol></li><li class="tocline"><a class="tocxref" href="#htmlmediaelement-events"><bdi class="secno">7.2 </bdi>Event Summary</a></li><li class="tocline"><a class="tocxref" href="#htmlmediaelement-algorithms"><bdi class="secno">7.3 </bdi>Algorithms</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#media-may-contain-encrypted-blocks"><bdi class="secno">7.3.1 </bdi>Media Data May Contain Encrypted Blocks</a></li><li class="tocline"><a class="tocxref" href="#initdata-encountered"><bdi class="secno">7.3.2 </bdi>Initialization Data Encountered</a></li><li class="tocline"><a class="tocxref" href="#encrypted-block-encountered"><bdi class="secno">7.3.3 </bdi>Encrypted Block Encountered</a></li><li class="tocline"><a class="tocxref" href="#attempt-to-decrypt"><bdi class="secno">7.3.4 </bdi>Attempt to Decrypt</a></li><li class="tocline"><a class="tocxref" href="#wait-for-key"><bdi class="secno">7.3.5 </bdi>Wait for Key</a></li><li class="tocline"><a class="tocxref" href="#resume-playback"><bdi class="secno">7.3.6 </bdi>Attempt to Resume Playback If Necessary</a></li></ol></li><li class="tocline"><a class="tocxref" href="#media-element-restrictions"><bdi class="secno">7.4 </bdi>Media Element Restrictions</a></li></ol></li><li class="tocline"><a class="tocxref" href="#implementation-requirements"><bdi class="secno">8. </bdi>Implementation Requirements</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#cdm-constraint-requirements"><bdi class="secno">8.1 </bdi>CDM Constraints</a></li><li class="tocline"><a class="tocxref" href="#messaging-requirements"><bdi class="secno">8.2 </bdi>Messages and Communication</a></li><li class="tocline"><a class="tocxref" href="#persistent-state-requirements"><bdi class="secno">8.3 </bdi>Persistent Data</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#use-origin-specific-key-system-storage"><bdi class="secno">8.3.1 </bdi>Use origin-specific and browsing profile-specific Key System storage</a></li><li class="tocline"><a class="tocxref" href="#allow-persistent-data-cleared"><bdi class="secno">8.3.2 </bdi>Allow Persistent Data to Be Cleared</a></li><li class="tocline"><a class="tocxref" href="#encrypt-or-obfuscate-persistent-data"><bdi class="secno">8.3.3 </bdi>Encrypt or obfuscate Persistent Data</a></li></ol></li><li class="tocline"><a class="tocxref" href="#exposed-value-requirements"><bdi class="secno">8.4 </bdi>Values Exposed to the Application</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#per-origin-per-profile-values"><bdi class="secno">8.4.1 </bdi>Use Per-Origin Per-Profile Values</a></li><li class="tocline"><a class="tocxref" href="#allow-values-to-be-cleared"><bdi class="secno">8.4.2 </bdi>Allow Values to Be Cleared</a></li></ol></li><li class="tocline"><a class="tocxref" href="#identifier-requirements"><bdi class="secno">8.5 </bdi>Identifiers</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#limit-or-avoid-use-of-distinctive-identifiers-and-permanent-identifiers"><bdi class="secno">8.5.1 </bdi>Limit or Avoid use of Distinctive Identifiers and Permanent Identifiers</a></li><li class="tocline"><a class="tocxref" href="#encrypt-identifiers"><bdi class="secno">8.5.2 </bdi>Encrypt Identifiers</a></li><li class="tocline"><a class="tocxref" href="#per-origin-per-profile-identifiers"><bdi class="secno">8.5.3 </bdi>Use Per-Origin Per-Profile Identifiers</a></li><li class="tocline"><a class="tocxref" href="#non-associable-identifiers"><bdi class="secno">8.5.4 </bdi>Use Non-Associable Identifiers</a></li><li class="tocline"><a class="tocxref" href="#allow-identifiers-cleared"><bdi class="secno">8.5.5 </bdi>Allow Identifiers to Be Cleared</a></li></ol></li><li class="tocline"><a class="tocxref" href="#individualization"><bdi class="secno">8.6 </bdi>Individualization</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#direct-individualization"><bdi class="secno">8.6.1 </bdi>Direct Individualization</a></li><li class="tocline"><a class="tocxref" href="#app-assisted-individualization"><bdi class="secno">8.6.2 </bdi>App-Assisted Individualization</a></li></ol></li><li class="tocline"><a class="tocxref" href="#support-multiple-keys"><bdi class="secno">8.7 </bdi>Support Multiple Keys</a></li><li class="tocline"><a class="tocxref" href="#initialization-data-type-support-requirements"><bdi class="secno">8.8 </bdi>Initialization Data Type Support</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#licenses-generated-are-independent-of-content-type"><bdi class="secno">8.8.1 </bdi>Licenses Generated are Independent of Content Type</a></li><li class="tocline"><a class="tocxref" href="#support-extraction-from-media-data"><bdi class="secno">8.8.2 </bdi>Support Extraction From Media Data</a></li></ol></li><li class="tocline"><a class="tocxref" href="#media-requirements"><bdi class="secno">8.9 </bdi>Supported Media</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#unencrypted-container"><bdi class="secno">8.9.1 </bdi>Unencrypted Container</a></li><li class="tocline"><a class="tocxref" href="#interoperably-encrypted"><bdi class="secno">8.9.2 </bdi>Interoperably Encrypted</a></li><li class="tocline"><a class="tocxref" href="#unencrypted-in-band-support-content"><bdi class="secno">8.9.3 </bdi>Unencrypted In-band Support Content</a></li></ol></li></ol></li><li class="tocline"><a class="tocxref" href="#common-key-systems"><bdi class="secno">9. </bdi>Common Key Systems</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#clear-key"><bdi class="secno">9.1 </bdi>Clear Key</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#clear-key-capabilities"><bdi class="secno">9.1.1 </bdi>Capabilities</a></li><li class="tocline"><a class="tocxref" href="#clear-key-behavior"><bdi class="secno">9.1.2 </bdi>Behavior</a></li><li class="tocline"><a class="tocxref" href="#clear-key-request-format"><bdi class="secno">9.1.3 </bdi>License Request Format</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#clear-key-request-format-example"><bdi class="secno">9.1.3.1 </bdi>Example</a></li></ol></li><li class="tocline"><a class="tocxref" href="#clear-key-license-format"><bdi class="secno">9.1.4 </bdi>License Format</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#clear-key-license-format-example"><bdi class="secno">9.1.4.1 </bdi>Example</a></li></ol></li><li class="tocline"><a class="tocxref" href="#clear-key-release-format"><bdi class="secno">9.1.5 </bdi>License Release Format</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#clear-key-release-format-example-1"><bdi class="secno">9.1.5.1 </bdi>Example message reflecting a <span def-id="record-of-license-destruction" class="formerLink"></span></a></li><li class="tocline"><a class="tocxref" href="#clear-key-release-format-example-2"><bdi class="secno">9.1.5.2 </bdi>Example message reflecting a <span def-id="record-of-key-usage" class="formerLink"></span></a></li></ol></li><li class="tocline"><a class="tocxref" href="#clear-key-release-ack-format"><bdi class="secno">9.1.6 </bdi>License Release Acknowledgement Format</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#clear-key-release-ack-format-example"><bdi class="secno">9.1.6.1 </bdi>Example</a></li></ol></li><li class="tocline"><a class="tocxref" href="#using-base64url"><bdi class="secno">9.1.7 </bdi>Using base64url</a></li></ol></li></ol></li><li class="tocline"><a class="tocxref" href="#security"><bdi class="secno">10. </bdi>Security</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#input-data-security"><bdi class="secno">10.1 </bdi>Input Data Attacks and Vulnerabilities</a></li><li class="tocline"><a class="tocxref" href="#cdm-security"><bdi class="secno">10.2 </bdi>CDM Attacks and Vulnerabilities</a></li><li class="tocline"><a class="tocxref" href="#network-attacks"><bdi class="secno">10.3 </bdi>Network Attacks</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#potential-attacks"><bdi class="secno">10.3.1 </bdi>Potential Attacks</a></li><li class="tocline"><a class="tocxref" href="#mitigations"><bdi class="secno">10.3.2 </bdi>Mitigations</a></li></ol></li><li class="tocline"><a class="tocxref" href="#iframe-attacks"><bdi class="secno">10.4 </bdi><code>iframe</code> Attacks</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#potential-attacks-0"><bdi class="secno">10.4.1 </bdi>Potential Attacks</a></li><li class="tocline"><a class="tocxref" href="#mitigations-0"><bdi class="secno">10.4.2 </bdi>Mitigations</a></li></ol></li><li class="tocline"><a class="tocxref" href="#cross-directory-attacks"><bdi class="secno">10.5 </bdi>Cross-Directory Attacks</a></li></ol></li><li class="tocline"><a class="tocxref" href="#privacy"><bdi class="secno">11. </bdi>Privacy</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#privacy-disclosure"><bdi class="secno">11.1 </bdi>Information Disclosed by EME and Key Systems</a></li><li class="tocline"><a class="tocxref" href="#privacy-fingerprinting"><bdi class="secno">11.2 </bdi>Fingerprinting</a></li><li class="tocline"><a class="tocxref" href="#privacy-leakage"><bdi class="secno">11.3 </bdi>Information Leakage</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#concerns"><bdi class="secno">11.3.1 </bdi>Concerns</a></li><li class="tocline"><a class="tocxref" href="#mitigations-1"><bdi class="secno">11.3.2 </bdi>Mitigations</a></li></ol></li><li class="tocline"><a class="tocxref" href="#user-tracking"><bdi class="secno">11.4 </bdi>User Tracking</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#concerns-0"><bdi class="secno">11.4.1 </bdi>Concerns</a></li><li class="tocline"><a class="tocxref" href="#mitigations-2"><bdi class="secno">11.4.2 </bdi>Mitigations</a></li></ol></li><li class="tocline"><a class="tocxref" href="#privacy-storedinfo"><bdi class="secno">11.5 </bdi>Information Stored on User Devices</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#concerns-1"><bdi class="secno">11.5.1 </bdi>Concerns</a></li><li class="tocline"><a class="tocxref" href="#mitigations-3"><bdi class="secno">11.5.2 </bdi>Mitigations</a></li></ol></li><li class="tocline"><a class="tocxref" href="#incomplete-clearing"><bdi class="secno">11.6 </bdi>Incomplete Clearing of Data</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#concerns-2"><bdi class="secno">11.6.1 </bdi>Concerns</a></li><li class="tocline"><a class="tocxref" href="#mitigations-4"><bdi class="secno">11.6.2 </bdi>Mitigations</a></li></ol></li><li class="tocline"><a class="tocxref" href="#private-browsing"><bdi class="secno">11.7 </bdi>Private Browsing Modes</a></li><li class="tocline"><a class="tocxref" href="#privacy-secureorigin"><bdi class="secno">11.8 </bdi>Secure Origin and Transport</a></li></ol></li><li class="tocline"><a class="tocxref" href="#conformance"><bdi class="secno">12. </bdi>Conformance</a></li><li class="tocline"><a class="tocxref" href="#examples"><bdi class="secno">13. </bdi>Examples</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#example-source-and-key-known"><bdi class="secno">13.1 </bdi>Source and Key Known at Page Load (Clear Key)</a></li><li class="tocline"><a class="tocxref" href="#example-selecting-key-system"><bdi class="secno">13.2 </bdi>Selecting a Supported Key System and Using Initialization Data from the "encrypted" Event</a></li><li class="tocline"><a class="tocxref" href="#example-mediakeys-before-source"><bdi class="secno">13.3 </bdi>Create MediaKeys Before Loading Media</a></li><li class="tocline"><a class="tocxref" href="#example-using-all-events"><bdi class="secno">13.4 </bdi>Using All Events</a></li><li class="tocline"><a class="tocxref" href="#example-stored-license"><bdi class="secno">13.5 </bdi>Stored License</a></li></ol></li><li class="tocline"><a class="tocxref" href="#acknowledgements"><bdi class="secno">14. </bdi>Acknowledgments</a></li><li class="tocline"><a class="tocxref" href="#references"><bdi class="secno">A. </bdi>References</a><ol class="toc"><li class="tocline"><a class="tocxref" href="#normative-references"><bdi class="secno">A.1 </bdi>Normative references</a></li><li class="tocline"><a class="tocxref" href="#informative-references"><bdi class="secno">A.2 </bdi>Informative references</a></li></ol></li></ol></nav>
<section id="introduction" class="informative">
<h2 id="x1-introduction"><bdi class="secno">1. </bdi>Introduction<a class="self-link" aria-label="§" href="#introduction"></a></h2><p><em>This section is non-normative.</em></p>
<p>
This specification enables script to select content protection mechanisms, control license/key exchange, and
execute custom license management algorithms.
It supports a wide range of use cases without requiring client-side modifications in each user agent for each use case.
This enables content providers to develop a single application solution for all devices.
</p>