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WD.html
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<!doctype html><html lang="en">
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<meta content="width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport">
<title>Content Security Policy Level 3</title>
<meta content="WD" name="w3c-status">
<link href="https://www.w3.org/StyleSheets/TR/2016/W3C-WD" rel="stylesheet" type="text/css">
<meta content="Bikeshed version fbf1456a756299b3ff6d248d0857ec87f2e68cd7" name="generator">
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<body class="h-entry">
<div class="head">
<p data-fill-with="logo"><a class="logo" href="https://www.w3.org/"> <img alt="W3C" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C" width="72"> </a> </p>
<h1>Content Security Policy Level 3</h1>
<h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">W3C Working Draft, <time class="dt-updated" datetime="2017-12-01">1 December 2017</time></span></h2>
<div data-fill-with="spec-metadata">
<dl>
<dt>This version:
<dd><a class="u-url" href="https://www.w3.org/TR/2017/WD-csp3-20171201/">https://www.w3.org/TR/2017/WD-csp3-20171201/</a>
<dt>Latest published version:
<dd><a href="https://www.w3.org/TR/CSP3/">https://www.w3.org/TR/CSP3/</a>
<dt>Editor's Draft:
<dd><a href="https://w3c.github.io/webappsec-csp/">https://w3c.github.io/webappsec-csp/</a>
<dt>Previous Versions:
<dd><a href="https://www.w3.org/TR/2016/WD-CSP3-20160913/" rel="prev">https://www.w3.org/TR/2016/WD-CSP3-20160913/</a>
<dt>Version History:
<dd><a href="https://github.com/w3c/webappsec-csp/commits/master/index.src.html">https://github.com/w3c/webappsec-csp/commits/master/index.src.html</a>
<dt>Feedback:
<dd><span><a href="mailto:public-webappsec@w3.org?subject=%5Bcsp3%5D%20YOUR%20TOPIC%20HERE">public-webappsec@w3.org</a> with subject line “<kbd>[csp3] <i data-lt="">… message topic …</i></kbd>” (<a href="https://lists.w3.org/Archives/Public/public-webappsec/" rel="discussion">archives</a>)</span>
<dt class="editor">Editor:
<dd class="editor p-author h-card vcard" data-editor-id="56384"><a class="p-name fn u-email email" href="mailto:mkwst@google.com">Mike West</a> (<span class="p-org org">Google Inc.</span>)
<dt>Participate:
<dd><a href="https://github.com/w3c/webappsec-csp/issues/new">File an issue</a> (<a href="https://github.com/w3c/webappsec-csp/issues">open issues</a>)
<dt>Tests:
<dd><a href="https://github.com/web-platform-tests/wpt/tree/master/content-security-policy">web-platform-tests content-security-policy/</a> (<a href="https://github.com/web-platform-tests/wpt/labels/content-security-policy">ongoing work</a>)
</dl>
</div>
<div data-fill-with="warning"></div>
<p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 2017 <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="http://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 href="https://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply. </p>
<hr title="Separator for header">
</div>
<div class="p-summary" data-fill-with="abstract">
<h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
<p>This document defines a mechanism by which web developers can control the
resources which a particular page can fetch or execute, as well as a number
of security-relevant policy decisions.</p>
</div>
<h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
<div data-fill-with="status">
<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 W3C publications and the latest revision of this technical report
can be found in the <a href="https://www.w3.org/TR/">W3C technical reports
index at https://www.w3.org/TR/.</a></em> </p>
<p> This document was published by the <a href="https://www.w3.org/2011/webappsec/">Web Application Security Working Group</a> as a Working Draft. This document is intended to become a W3C Recommendation. </p>
<p> The (<a href="https://lists.w3.org/Archives/Public/public-webappsec/">archived</a>) public mailing list <a href="mailto:public-webappsec@w3.org?Subject=%5Bcsp3%5D%20PUT%20SUBJECT%20HERE">public-webappsec@w3.org</a> (see <a href="https://www.w3.org/Mail/Request">instructions</a>)
is preferred for discussion of this specification.
When sending e-mail,
please put the text “csp3” in the subject,
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<p> Publication as a Working Draft does not imply endorsement by the W3C
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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 the <a href="https://www.w3.org/2011/webappsec/">Web Application Security Working Group</a>. </p>
<p> This document was produced by a group operating under
the <a href="https://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 W3C Patent Policy</a>.
W3C maintains a <a href="https://www.w3.org/2004/01/pp-impl/49309/status" rel="disclosure">public list of any patent disclosures</a> made in connection with the deliverables of the group;
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An individual who has actual knowledge of a patent which the individual believes contains <a href="https://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="https://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
<p> This document is governed by the <a href="https://www.w3.org/2017/Process-20170301/" id="w3c_process_revision">1 March 2017 W3C Process Document</a>. </p>
<p></p>
</div>
<div data-fill-with="at-risk">
<p>The following features are at-risk, and may be dropped during the CR period: </p>
<ul>
<li>The <a href="#is-element-nonceable">§6.6.2.1 Is element nonceable?</a> algorithm.
</ul>
<p>“At-risk” is a W3C Process term-of-art, and does not necessarily imply that the feature is in danger of being dropped or delayed. It means that the WG believes the feature may have difficulty being interoperably implemented in a timely manner, and marking it as such allows the WG to drop the feature if necessary when transitioning to the Proposed Rec stage, without having to publish a new Candidate Rec without the feature first.</p>
</div>
<nav data-fill-with="table-of-contents" id="toc">
<h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
<ol class="toc" role="directory">
<li>
<a href="#intro"><span class="secno">1</span> <span class="content">Introduction</span></a>
<ol class="toc">
<li>
<a href="#examples"><span class="secno">1.1</span> <span class="content">Examples</span></a>
<ol class="toc">
<li><a href="#example-basic"><span class="secno">1.1.1</span> <span class="content">Control Execution</span></a>
</ol>
<li><a href="#goals"><span class="secno">1.2</span> <span class="content">Goals</span></a>
<li><a href="#changes-from-level-2"><span class="secno">1.3</span> <span class="content">Changes from Level 2</span></a>
</ol>
<li>
<a href="#framework"><span class="secno">2</span> <span class="content">Framework</span></a>
<ol class="toc">
<li><a href="#framework-infrastructure"><span class="secno">2.1</span> <span class="content">Infrastructure</span></a>
<li>
<a href="#framework-policy"><span class="secno">2.2</span> <span class="content">Policies</span></a>
<ol class="toc">
<li><a href="#parse-serialized-policy"><span class="secno">2.2.1</span> <span class="content"> Parse a serialized CSP </span></a>
<li><a href="#parse-serialized-policy-list"><span class="secno">2.2.2</span> <span class="content"> Parse a serialized CSP list </span></a>
</ol>
<li>
<a href="#framework-directives"><span class="secno">2.3</span> <span class="content">Directives</span></a>
<ol class="toc">
<li><a href="#framework-directive-source-list"><span class="secno">2.3.1</span> <span class="content">Source Lists</span></a>
</ol>
<li>
<a href="#framework-violation"><span class="secno">2.4</span> <span class="content">Violations</span></a>
<ol class="toc">
<li><a href="#create-violation-for-global"><span class="secno">2.4.1</span> <span class="content"> Create a violation object for <var>global</var>, <var>policy</var>, and <var>directive</var> </span></a>
<li><a href="#create-violation-for-request"><span class="secno">2.4.2</span> <span class="content"> Create a violation object for <var>request</var>, <var>policy</var>, and <var>directive</var> </span></a>
</ol>
</ol>
<li>
<a href="#policy-delivery"><span class="secno">3</span> <span class="content"> Policy Delivery </span></a>
<ol class="toc">
<li><a href="#csp-header"><span class="secno">3.1</span> <span class="content"> The <code>Content-Security-Policy</code> HTTP Response Header Field </span></a>
<li><a href="#cspro-header"><span class="secno">3.2</span> <span class="content"> The <code>Content-Security-Policy-Report-Only</code> HTTP Response Header Field </span></a>
<li><a href="#meta-element"><span class="secno">3.3</span> <span class="content"> The <code><meta></code> element </span></a>
</ol>
<li>
<a href="#integrations"><span class="secno">4</span> <span class="content">Integrations</span></a>
<ol class="toc">
<li>
<a href="#fetch-integration"><span class="secno">4.1</span> <span class="content"> Integration with Fetch </span></a>
<ol class="toc">
<li><a href="#set-response-csp-list"><span class="secno">4.1.1</span> <span class="content"> Set <var>response</var>’s <code>CSP list</code> </span></a>
<li><a href="#report-for-request"><span class="secno">4.1.2</span> <span class="content"> Report Content Security Policy violations for <var>request</var> </span></a>
<li><a href="#should-block-request"><span class="secno">4.1.3</span> <span class="content"> Should <var>request</var> be blocked by Content Security Policy? </span></a>
<li><a href="#should-block-response"><span class="secno">4.1.4</span> <span class="content"> Should <var>response</var> to <var>request</var> be blocked by Content
Security Policy? </span></a>
</ol>
<li>
<a href="#html-integration"><span class="secno">4.2</span> <span class="content"> Integration with HTML </span></a>
<ol class="toc">
<li><a href="#initialize-document-csp"><span class="secno">4.2.1</span> <span class="content"> Initialize a <code>Document</code>'s <code>CSP list</code> </span></a>
<li><a href="#initialize-global-object-csp"><span class="secno">4.2.2</span> <span class="content"> Initialize a global object’s <code>CSP list</code> </span></a>
<li><a href="#get-csp-of-object"><span class="secno">4.2.3</span> <span class="content"> Retrieve the <span>CSP list</span> of an <var>object</var> </span></a>
<li><a href="#should-block-inline"><span class="secno">4.2.4</span> <span class="content"> Should <var>element</var>’s inline <var>type</var> behavior be blocked by Content Security Policy? </span></a>
<li><a href="#should-block-navigation-request"><span class="secno">4.2.5</span> <span class="content"> Should <var>navigation request</var> of <var>type</var> from <var>source</var> in <var>target</var> be blocked
by Content Security Policy? </span></a>
<li><a href="#should-block-navigation-response"><span class="secno">4.2.6</span> <span class="content"> Should <var>navigation response</var> to <var>navigation request</var> of <var>type</var> from <var>source</var> in <var>target</var> be blocked by Content Security Policy? </span></a>
</ol>
<li>
<a href="#ecma-integration"><span class="secno">4.3</span> <span class="content">Integration with ECMAScript</span></a>
<ol class="toc">
<li><a href="#can-compile-strings"><span class="secno">4.3.1</span> <span class="content"> EnsureCSPDoesNotBlockStringCompilation(<var>callerRealm</var>, <var>calleeRealm</var>, <var>source</var>) </span></a>
</ol>
</ol>
<li>
<a href="#reporting"><span class="secno">5</span> <span class="content"> Reporting </span></a>
<ol class="toc">
<li><a href="#violation-events"><span class="secno">5.1</span> <span class="content"> Violation DOM Events </span></a>
<li><a href="#deprecated-serialize-violation"><span class="secno">5.2</span> <span class="content"> Obtain the deprecated serialization of <var>violation</var> </span></a>
<li><a href="#report-violation"><span class="secno">5.3</span> <span class="content"> Report a <var>violation</var> </span></a>
</ol>
<li>
<a href="#csp-directives"><span class="secno">6</span> <span class="content"> Content Security Policy Directives </span></a>
<ol class="toc">
<li>
<a href="#directives-fetch"><span class="secno">6.1</span> <span class="content"> Fetch Directives </span></a>
<ol class="toc">
<li>
<a href="#directive-child-src"><span class="secno">6.1.1</span> <span class="content"><code>child-src</code></span></a>
<ol class="toc">
<li><a href="#child-src-pre-request"><span class="secno">6.1.1.1</span> <span class="content"> <code>child-src</code> Pre-request check </span></a>
<li><a href="#child-src-post-request"><span class="secno">6.1.1.2</span> <span class="content"> <code>child-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-connect-src"><span class="secno">6.1.2</span> <span class="content"><code>connect-src</code></span></a>
<ol class="toc">
<li><a href="#connect-src-pre-request"><span class="secno">6.1.2.1</span> <span class="content"> <code>connect-src</code> Pre-request check </span></a>
<li><a href="#connect-src-post-request"><span class="secno">6.1.2.2</span> <span class="content"> <code>connect-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-default-src"><span class="secno">6.1.3</span> <span class="content"><code>default-src</code></span></a>
<ol class="toc">
<li><a href="#default-src-pre-request"><span class="secno">6.1.3.1</span> <span class="content"> <code>default-src</code> Pre-request check </span></a>
<li><a href="#default-src-post-request"><span class="secno">6.1.3.2</span> <span class="content"> <code>default-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-font-src"><span class="secno">6.1.4</span> <span class="content"><code>font-src</code></span></a>
<ol class="toc">
<li><a href="#font-src-pre-request"><span class="secno">6.1.4.1</span> <span class="content"> <code>font-src</code> Pre-request check </span></a>
<li><a href="#font-src-post-request"><span class="secno">6.1.4.2</span> <span class="content"> <code>font-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-frame-src"><span class="secno">6.1.5</span> <span class="content"><code>frame-src</code></span></a>
<ol class="toc">
<li><a href="#frame-src-pre-request"><span class="secno">6.1.5.1</span> <span class="content"> <code>frame-src</code> Pre-request check </span></a>
<li><a href="#frame-src-post-request"><span class="secno">6.1.5.2</span> <span class="content"> <code>frame-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-img-src"><span class="secno">6.1.6</span> <span class="content"><code>img-src</code></span></a>
<ol class="toc">
<li><a href="#img-src-pre-request"><span class="secno">6.1.6.1</span> <span class="content"> <code>img-src</code> Pre-request check </span></a>
<li><a href="#img-src-post-request"><span class="secno">6.1.6.2</span> <span class="content"> <code>img-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-manifest-src"><span class="secno">6.1.7</span> <span class="content"><code>manifest-src</code></span></a>
<ol class="toc">
<li><a href="#manifest-src-pre-request"><span class="secno">6.1.7.1</span> <span class="content"> <code>manifest-src</code> Pre-request check </span></a>
<li><a href="#manifest-src-post-request"><span class="secno">6.1.7.2</span> <span class="content"> <code>manifest-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-media-src"><span class="secno">6.1.8</span> <span class="content"><code>media-src</code></span></a>
<ol class="toc">
<li><a href="#media-src-pre-request"><span class="secno">6.1.8.1</span> <span class="content"> <code>media-src</code> Pre-request check </span></a>
<li><a href="#media-src-post-request"><span class="secno">6.1.8.2</span> <span class="content"> <code>media-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-object-src"><span class="secno">6.1.9</span> <span class="content"><code>object-src</code></span></a>
<ol class="toc">
<li><a href="#object-src-pre-request"><span class="secno">6.1.9.1</span> <span class="content"> <code>object-src</code> Pre-request check </span></a>
<li><a href="#object-src-post-request"><span class="secno">6.1.9.2</span> <span class="content"> <code>object-src</code> Post-request check </span></a>
</ol>
<li>
<a href="#directive-script-src"><span class="secno">6.1.10</span> <span class="content"><code>script-src</code></span></a>
<ol class="toc">
<li><a href="#script-src-pre-request"><span class="secno">6.1.10.1</span> <span class="content"> <code>script-src</code> Pre-request check </span></a>
<li><a href="#script-src-post-request"><span class="secno">6.1.10.2</span> <span class="content"> <code>script-src</code> Post-request check </span></a>
<li><a href="#script-src-inline"><span class="secno">6.1.10.3</span> <span class="content"> <code>script-src</code> Inline Check </span></a>
</ol>
<li>
<a href="#directive-style-src"><span class="secno">6.1.11</span> <span class="content"><code>style-src</code></span></a>
<ol class="toc">
<li><a href="#style-src-pre-request"><span class="secno">6.1.11.1</span> <span class="content"> <code>style-src</code> Pre-request Check </span></a>
<li><a href="#style-src-post-request"><span class="secno">6.1.11.2</span> <span class="content"> <code>style-src</code> Post-request Check </span></a>
<li><a href="#style-src-inline"><span class="secno">6.1.11.3</span> <span class="content"> <code>style-src</code> Inline Check </span></a>
</ol>
<li>
<a href="#directive-worker-src"><span class="secno">6.1.12</span> <span class="content"><code>worker-src</code></span></a>
<ol class="toc">
<li><a href="#worker-src-pre-request"><span class="secno">6.1.12.1</span> <span class="content"> <code>worker-src</code> Pre-request Check </span></a>
<li><a href="#worker-src-post-request"><span class="secno">6.1.12.2</span> <span class="content"> <code>worker-src</code> Post-request Check </span></a>
</ol>
</ol>
<li>
<a href="#directives-document"><span class="secno">6.2</span> <span class="content"> Document Directives </span></a>
<ol class="toc">
<li>
<a href="#directive-base-uri"><span class="secno">6.2.1</span> <span class="content"><code>base-uri</code></span></a>
<ol class="toc">
<li><a href="#allow-base-for-document"><span class="secno">6.2.1.1</span> <span class="content"> Is <var>base</var> allowed for <var>document</var>? </span></a>
</ol>
<li>
<a href="#directive-plugin-types"><span class="secno">6.2.2</span> <span class="content"><code>plugin-types</code></span></a>
<ol class="toc">
<li><a href="#plugin-types-post-request-check"><span class="secno">6.2.2.1</span> <span class="content"> <code>plugin-types</code> Post-Request Check </span></a>
<li><a href="#should-plugin-element-be-blocked-a-priori-by-content-security-policy"><span class="secno">6.2.2.2</span> <span class="content"> Should <var>plugin element</var> be blocked <i lang="la">a priori</i> by Content
Security Policy?: </span></a>
</ol>
<li>
<a href="#directive-sandbox"><span class="secno">6.2.3</span> <span class="content"><code>sandbox</code></span></a>
<ol class="toc">
<li><a href="#sandbox-response"><span class="secno">6.2.3.1</span> <span class="content"> <code>sandbox</code> Response Check </span></a>
<li><a href="#sandbox-init"><span class="secno">6.2.3.2</span> <span class="content"> <code>sandbox</code> Initialization </span></a>
</ol>
<li>
<a href="#directive-disown-opener"><span class="secno">6.2.4</span> <span class="content"><code>disown-opener</code></span></a>
<ol class="toc">
<li><a href="#disown-opener-init"><span class="secno">6.2.4.1</span> <span class="content"> <code>disown-opener</code> Initialization </span></a>
</ol>
</ol>
<li>
<a href="#directives-navigation"><span class="secno">6.3</span> <span class="content"> Navigation Directives </span></a>
<ol class="toc">
<li>
<a href="#directive-form-action"><span class="secno">6.3.1</span> <span class="content"><code>form-action</code></span></a>
<ol class="toc">
<li><a href="#form-action-pre-navigate"><span class="secno">6.3.1.1</span> <span class="content"> <code>form-action</code> Pre-Navigation Check </span></a>
</ol>
<li>
<a href="#directive-frame-ancestors"><span class="secno">6.3.2</span> <span class="content"><code>frame-ancestors</code></span></a>
<ol class="toc">
<li><a href="#frame-ancestors-navigation-response"><span class="secno">6.3.2.1</span> <span class="content"> <code>frame-ancestors</code> Navigation Response Check </span></a>
<li><a href="#frame-ancestors-and-frame-options"><span class="secno">6.3.2.2</span> <span class="content"> Relation to <code>X-Frame-Options</code> </span></a>
</ol>
<li>
<a href="#directive-navigation-to"><span class="secno">6.3.3</span> <span class="content"><code>navigation-to</code></span></a>
<ol class="toc">
<li><a href="#navigation-to-pre-navigate"><span class="secno">6.3.3.1</span> <span class="content"> <code>navigation-to</code> Pre-Navigation Check </span></a>
</ol>
</ol>
<li>
<a href="#directives-reporting"><span class="secno">6.4</span> <span class="content"> Reporting Directives </span></a>
<ol class="toc">
<li><a href="#directive-report-uri"><span class="secno">6.4.1</span> <span class="content"><code>report-uri</code></span></a>
<li><a href="#directive-report-to"><span class="secno">6.4.2</span> <span class="content"><code>report-to</code></span></a>
</ol>
<li><a href="#directives-elsewhere"><span class="secno">6.5</span> <span class="content"> Directives Defined in Other Documents </span></a>
<li>
<a href="#algorithms"><span class="secno">6.6</span> <span class="content">Matching Algorithms</span></a>
<ol class="toc">
<li>
<a href="#matching-urls"><span class="secno">6.6.1</span> <span class="content">URL Matching</span></a>
<ol class="toc">
<li><a href="#does-request-violate-policy"><span class="secno">6.6.1.1</span> <span class="content"> Does <var>request</var> violate <var>policy</var>? </span></a>
<li><a href="#match-nonce-to-source-list"><span class="secno">6.6.1.2</span> <span class="content"> Does <var>nonce</var> match <var>source list</var>? </span></a>
<li><a href="#match-request-to-source-list"><span class="secno">6.6.1.3</span> <span class="content"> Does <var>request</var> match <var>source list</var>? </span></a>
<li><a href="#match-response-to-source-list"><span class="secno">6.6.1.4</span> <span class="content"> Does <var>response</var> to <var>request</var> match <var>source list</var>? </span></a>
<li><a href="#match-url-to-source-list"><span class="secno">6.6.1.5</span> <span class="content"> Does <var>url</var> match <var>source list</var> in <var>origin</var> with <var>redirect count</var>? </span></a>
<li><a href="#match-url-to-source-expression"><span class="secno">6.6.1.6</span> <span class="content"> Does <var>url</var> match <var>expression</var> in <var>origin</var> with <var>redirect count</var>? </span></a>
<li><a href="#match-schemes"><span class="secno">6.6.1.7</span> <span class="content"> <code>scheme-part</code> matching </span></a>
<li><a href="#match-hosts"><span class="secno">6.6.1.8</span> <span class="content"> <code>host-part</code> matching </span></a>
<li><a href="#match-ports"><span class="secno">6.6.1.9</span> <span class="content"> <code>port-part</code> matching </span></a>
<li><a href="#match-paths"><span class="secno">6.6.1.10</span> <span class="content"> <code>path-part</code> matching </span></a>
<li><a href="#effective-directive-for-a-request"><span class="secno">6.6.1.11</span> <span class="content"> Get the effective directive for <var>request</var> </span></a>
</ol>
<li>
<a href="#matching-elements"><span class="secno">6.6.2</span> <span class="content">Element Matching Algorithms</span></a>
<ol class="toc">
<li><a href="#is-element-nonceable"><span class="secno">6.6.2.1</span> <span class="content"> Is <var>element</var> nonceable? </span></a>
<li><a href="#allow-all-inline"><span class="secno">6.6.2.2</span> <span class="content"> Does a source list allow all inline behavior for <var>type</var>? </span></a>
<li><a href="#match-element-to-source-list"><span class="secno">6.6.2.3</span> <span class="content"> Does <var>element</var> match source list for <var>type</var> and <var>source</var>? </span></a>
</ol>
</ol>
</ol>
<li>
<a href="#security-considerations"><span class="secno">7</span> <span class="content">Security and Privacy Considerations</span></a>
<ol class="toc">
<li><a href="#security-nonces"><span class="secno">7.1</span> <span class="content">Nonce Reuse</span></a>
<li><a href="#security-nonce-stealing"><span class="secno">7.2</span> <span class="content">Nonce Stealing</span></a>
<li><a href="#security-nonce-retargeting"><span class="secno">7.3</span> <span class="content">Nonce Retargeting</span></a>
<li><a href="#security-css-parsing"><span class="secno">7.4</span> <span class="content">CSS Parsing</span></a>
<li><a href="#security-violation-reports"><span class="secno">7.5</span> <span class="content">Violation Reports</span></a>
<li><a href="#source-list-paths-and-redirects"><span class="secno">7.6</span> <span class="content">Paths and Redirects</span></a>
<li><a href="#security-secure-upgrades"><span class="secno">7.7</span> <span class="content">Secure Upgrades</span></a>
<li><a href="#security-inherit-csp"><span class="secno">7.8</span> <span class="content"> CSP Inheriting to avoid bypasses </span></a>
</ol>
<li>
<a href="#authoring-considerations"><span class="secno">8</span> <span class="content">Authoring Considerations</span></a>
<ol class="toc">
<li><a href="#multiple-policies"><span class="secno">8.1</span> <span class="content"> The effect of multiple policies </span></a>
<li><a href="#strict-dynamic-usage"><span class="secno">8.2</span> <span class="content"> Usage of "<code>'strict-dynamic'</code>" </span></a>
<li><a href="#unsafe-hashed-attributes-usage"><span class="secno">8.3</span> <span class="content"> Usage of "<code>'unsafe-hashed-attributes'</code>" </span></a>
<li><a href="#external-hash"><span class="secno">8.4</span> <span class="content"> Allowing external JavaScript via hashes </span></a>
</ol>
<li>
<a href="#implementation-considerations"><span class="secno">9</span> <span class="content">Implementation Considerations</span></a>
<ol class="toc">
<li><a href="#extensions"><span class="secno">9.1</span> <span class="content">Vendor-specific Extensions and Addons</span></a>
</ol>
<li>
<a href="#iana-considerations"><span class="secno">10</span> <span class="content">IANA Considerations</span></a>
<ol class="toc">
<li><a href="#iana-registry"><span class="secno">10.1</span> <span class="content"> Directive Registry </span></a>
<li>
<a href="#iana-headers"><span class="secno">10.2</span> <span class="content"> Headers </span></a>
<ol class="toc">
<li><a href="#iana-csp"><span class="secno">10.2.1</span> <span class="content">Content-Security-Policy</span></a>
<li><a href="#iana-cspro"><span class="secno">10.2.2</span> <span class="content">Content-Security-Policy-Report-Only</span></a>
</ol>
</ol>
<li><a href="#acknowledgements"><span class="secno">11</span> <span class="content">Acknowledgements</span></a>
<li>
<a href="#conformance"><span class="secno"></span> <span class="content">Conformance</span></a>
<ol class="toc">
<li><a href="#conventions"><span class="secno"></span> <span class="content">Document conventions</span></a>
<li><a href="#conformant-algorithms"><span class="secno"></span> <span class="content">Conformant Algorithms</span></a>
</ol>
<li>
<a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
<ol class="toc">
<li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
<li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
</ol>
<li>
<a href="#references"><span class="secno"></span> <span class="content">References</span></a>
<ol class="toc">
<li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
<li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
</ol>
<li><a href="#idl-index"><span class="secno"></span> <span class="content">IDL Index</span></a>
<li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
</ol>
</nav>
<main>
<section>
<h2 class="heading settled" data-level="1" id="intro"><span class="secno">1. </span><span class="content">Introduction</span><a class="self-link" href="#intro"></a></h2>
<p><em>This section is not normative.</em></p>
<p>This document defines <dfn data-dfn-type="dfn" data-export="" id="content-security-policy">Content Security Policy<a class="self-link" href="#content-security-policy"></a></dfn> (CSP), a tool
which developers can use to lock down their applications in various ways,
mitigating the risk of content injection vulnerabilities such as cross-site scripting, and
reducing the privilege with which their applications execute.</p>
<p>CSP is not intended as a first line of defense against content injection
vulnerabilities. Instead, CSP is best used as defense-in-depth. It reduces
the harm that a malicious injection can cause, but it is not a replacement for
careful input validation and output encoding.</p>
<p>This document is an iteration on Content Security Policy Level 2, with the
goal of more clearly explaining the interactions between CSP, HTML, and Fetch
on the one hand, and providing clear hooks for modular extensibility on the
other. Ideally, this will form a stable core upon which we can build new
functionality.</p>
<h3 class="heading settled" data-level="1.1" id="examples"><span class="secno">1.1. </span><span class="content">Examples</span><a class="self-link" href="#examples"></a></h3>
<h4 class="heading settled" data-level="1.1.1" id="example-basic"><span class="secno">1.1.1. </span><span class="content">Control Execution</span><a class="self-link" href="#example-basic"></a></h4>
<div class="example" id="example-1451d1f8">
<a class="self-link" href="#example-1451d1f8"></a> MegaCorp Inc’s developers want to protect themselves against cross-site
scripting attacks. They can mitigate the risk of script injection by
ensuring that their trusted CDN is the only origin from which script can
load and execute. Moreover, they wish to ensure that no plugins can
execute in their pages' contexts. The following policy has that effect:
<pre>Content-Security-Policy: script-src https://cdn.example.com/scripts/; object-src 'none'
</pre>
</div>
<h3 class="heading settled" data-level="1.2" id="goals"><span class="secno">1.2. </span><span class="content">Goals</span><a class="self-link" href="#goals"></a></h3>
<p>Content Security Policy aims to do to a few related things:</p>
<ol>
<li data-md="">
<p>Mitigate the risk of content-injection attacks by giving developers
fairly granular control over</p>
<ul>
<li data-md="">
<p>The resources which can be requested (and subsequently embedded or
executed) on behalf of a specific <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#document" id="ref-for-document">Document</a></code> or <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#worker" id="ref-for-worker">Worker</a></code></p>
<li data-md="">
<p>The execution of inline script</p>
<li data-md="">
<p>Dynamic code execution (via <code class="idl"><a data-link-type="idl" href="https://tc39.github.io/ecma262#sec-eval-x" id="ref-for-sec-eval-x">eval()</a></code> and similar constructs)</p>
<li data-md="">
<p>The application of inline style</p>
</ul>
<li data-md="">
<p>Mitigate the risk of attacks which require a resource to be embedded
in a malicious context (the "Pixel Perfect" attack described in <a data-link-type="biblio" href="#biblio-timing">[TIMING]</a>, for example) by giving developers granular control over the
origins which can embed a given resource.</p>
<li data-md="">
<p>Provide a policy framework which allows developers to reduce the privilege
of their applications.</p>
<li data-md="">
<p>Provide a reporting mechanism which allows developers to detect flaws
being exploited in the wild.</p>
</ol>
<h3 class="heading settled" data-level="1.3" id="changes-from-level-2"><span class="secno">1.3. </span><span class="content">Changes from Level 2</span><a class="self-link" href="#changes-from-level-2"></a></h3>
<p>This document describes an evolution of the Content Security Policy Level 2
specification <a data-link-type="biblio" href="#biblio-csp2">[CSP2]</a>. The following is a high-level overview of the changes:</p>
<ol>
<li data-md="">
<p>The specification has been rewritten from the ground up in terms of the <a data-link-type="biblio" href="#biblio-fetch">[FETCH]</a> specification, which should make it simpler to integrate CSP’s
requirements and restrictions with other specifications (and with
Service Workers in particular).</p>
<li data-md="">
<p>The <code>child-src</code> model has been substantially altered:</p>
<ol>
<li data-md="">
<p>The <code>frame-src</code> directive, which was deprecated in CSP Level
2, has been undeprecated, but continues to defer to <code>child-src</code> if
not present (which defers to <code>default-src</code> in turn).</p>
<li data-md="">
<p>A <code>worker-src</code> directive has been added, deferring to <code>script-src</code> if not present (which likewise defers to <code>default-src</code> in turn).</p>
<li data-md="">
<p><code>child-src</code> is now deprecated.</p>
<li data-md="">
<p>Dedicated workers now always inherit their creator’s policy.</p>
</ol>
<li data-md="">
<p>The URL matching algorithm now treats insecure schemes and ports as
matching their secure variants. That is, the source expression <code>http://example.com:80</code> will match both <code>http://example.com:80</code> and <code>https://example.com:443</code>.</p>
<p>Likewise, <code>'self'</code> now matches <code>https:</code> and <code>wss:</code> variants of the page’s
origin, even on pages whose scheme is <code>http</code>.</p>
<li data-md="">
<p>Violation reports generated from inline script or style will now report
"<code>inline</code>" as the blocked resource. Likewise, blocked <code>eval()</code> execution
will report "<code>eval</code>" as the blocked resource.</p>
<li data-md="">
<p>The <code>manifest-src</code> directive has been added.</p>
<li data-md="">
<p>The <code>report-uri</code> directive is deprecated in favor of the new <code>report-to</code> directive, which relies on <a data-link-type="biblio" href="#biblio-reporting">[REPORTING]</a> as infrastructure.</p>
<li data-md="">
<p>The <code>'strict-dynamic'</code> source expression will now allow script which
executes on a page to load more script via non-<a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#parser-inserted" id="ref-for-parser-inserted">"parser-inserted"</a> <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/scripting.html#script" id="ref-for-script">script</a></code> elements. Details are in <a href="#strict-dynamic-usage">§8.2 Usage of "'strict-dynamic'"</a>.</p>
<li data-md="">
<div class="wip">
The <code>'unsafe-hashed-attributes'</code> source expression will now allow event
handlers and style attributes to match hash source expressions. Details
in <a href="#unsafe-hashed-attributes-usage">§8.3 Usage of "'unsafe-hashed-attributes'"</a>.
<p class="issue" id="issue-2f321613"><a class="self-link" href="#issue-2f321613"></a> <code>unsafe-hashed-attributes</code> is a work in progress. <a href="https://github.com/w3c/webappsec-csp/issues/13"><https://github.com/w3c/webappsec-csp/issues/13></a></p>
</div>
<li data-md="">
<p>The <a data-link-type="dfn" href="#source-expression" id="ref-for-source-expression">source expression</a> matching has been changed to require explicit presence
of any non-<a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#network-scheme" id="ref-for-network-scheme">network scheme</a>, rather than <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#local-scheme" id="ref-for-local-scheme">local scheme</a>,
unless that non-<a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#network-scheme" id="ref-for-network-scheme①">network scheme</a> is the same as the scheme of protected resource,
as described in <a href="#match-url-to-source-expression">§6.6.1.6 Does url match expression in origin with redirect count?</a>.</p>
<li data-md="">
<p>Hash-based source expressions may now match external scripts if the <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/scripting.html#script" id="ref-for-script①">script</a></code> element that triggers the request specifies a set of integrity
metadata which is listed in the current policy. Details in <a href="#external-hash">§8.4 Allowing external JavaScript via hashes</a>.</p>
<li data-md="">
<div class="wip">
The <a data-link-type="dfn" href="#disown-opener" id="ref-for-disown-opener"><code>disown-opener</code></a> directive ensures that a resource can’t be opened
in such a way as to give another browsing context control over its contents.
<p class="issue" id="issue-0915ad11"><a class="self-link" href="#issue-0915ad11"></a> <code>disown-opener</code> is a work in progress. <a href="https://github.com/w3c/webappsec-csp/issues/194"><https://github.com/w3c/webappsec-csp/issues/194></a></p>
</div>
<li data-md="">
<div class="wip">
The <a data-link-type="dfn" href="#navigation-to" id="ref-for-navigation-to"><code>navigation-to</code></a> directive gives a resource control over the endpoints
to which it can initiate navigation.
<p class="issue" id="issue-a305d3f5"><a class="self-link" href="#issue-a305d3f5"></a> <code>navigation-to</code> is a work in progress. <a href="https://github.com/w3c/webappsec-csp/issues/125"><https://github.com/w3c/webappsec-csp/issues/125></a></p>
</div>
<li data-md="">
<p>Reports generated for inline violations will contain a <a data-link-type="dfn" href="#violation-sample" id="ref-for-violation-sample">sample</a> attribute if the relevant directive contains the <a data-link-type="grammar" href="#grammardef-report-sample" id="ref-for-grammardef-report-sample"><code>'report-sample'</code></a> expression.</p>
</ol>
</section>
<section>
<h2 class="heading settled" data-level="2" id="framework"><span class="secno">2. </span><span class="content">Framework</span><a class="self-link" href="#framework"></a></h2>
<h3 class="heading settled" data-level="2.1" id="framework-infrastructure"><span class="secno">2.1. </span><span class="content">Infrastructure</span><a class="self-link" href="#framework-infrastructure"></a></h3>
<p>This document uses ABNF grammar to specify syntax, as defined in <a data-link-type="biblio" href="#biblio-rfc5234">[RFC5234]</a>. It also relies on
the <code>#rule</code> ABNF extension defined in <a href="https://tools.ietf.org/html/rfc7230#section-7">Section 7</a> of <a data-link-type="biblio" href="#biblio-rfc7230">[RFC7230]</a>.</p>
<p>This document depends on the Infra Standard for a number of foundational concepts used in its
algorithms and prose <a data-link-type="biblio" href="#biblio-infra">[INFRA]</a>.</p>
<h3 class="heading settled" data-level="2.2" id="framework-policy"><span class="secno">2.2. </span><span class="content">Policies</span><a class="self-link" href="#framework-policy"></a></h3>
<p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" data-local-lt="policy" data-lt="content security policy object" id="content-security-policy-object">policy</dfn> defines allowed
and restricted behaviors, and may be applied to a <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/window-object.html#window" id="ref-for-window">Window</a></code>, <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope">WorkerGlobalScope</a></code>, or <code class="idl"><a data-link-type="idl" href="https://www.w3.org/TR/worklets-1/#workletglobalscope" id="ref-for-workletglobalscope">WorkletGlobalScope</a></code> as described in <a href="#initialize-global-object-csp">§4.2.2 Initialize a global object’s CSP list</a>.</p>
<p>Each policy has an associated <dfn class="dfn-paneled" data-dfn-for="policy" data-dfn-type="dfn" data-export="" id="policy-directive-set">directive set</dfn>, which is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-set" id="ref-for-ordered-set">ordered
set</a> of <a data-link-type="dfn" href="#directives" id="ref-for-directives">directives</a> that define the policy’s implications when applied.</p>
<p>Each policy has an associated <dfn class="dfn-paneled" data-dfn-for="policy" data-dfn-type="dfn" data-export="" id="policy-disposition">disposition</dfn>, which is either
"<code>enforce</code>" or "<code>report</code>".</p>
<p>Each policy has an associated <dfn class="dfn-paneled" data-dfn-for="policy" data-dfn-type="dfn" data-export="" id="policy-source">source</dfn>, which is either "<code>header</code>"
or "<code>meta</code>".</p>
<p>Multiple <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object">policies</a> can be applied to a single resource, and are collected into a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list" id="ref-for-list">list</a> of <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object①">policies</a> known as a <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="csp-list">CSP list</dfn>.</p>
<p>A <a data-link-type="dfn" href="#csp-list" id="ref-for-csp-list">CSP list</a> <dfn data-dfn-type="dfn" data-export="" id="contains-a-header-delivered-content-security-policy">contains a header-delivered Content Security Policy<a class="self-link" href="#contains-a-header-delivered-content-security-policy"></a></dfn> if it <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list-contain" id="ref-for-list-contain">contains</a> a <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object②">policy</a> whose <a data-link-type="dfn" href="#policy-source" id="ref-for-policy-source">source</a> is "<code>header</code>".</p>
<p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="serialized-csp">serialized CSP</dfn> is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ascii-string" id="ref-for-ascii-string">ASCII string</a> consisting of a semicolon-delimited
series of <a data-link-type="dfn" href="#serialized-directive" id="ref-for-serialized-directive">serialized directives</a>, adhering to the following ABNF grammar <a data-link-type="biblio" href="#biblio-rfc5234">[RFC5234]</a>:</p>
<pre><dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-serialized-policy">serialized-policy</dfn> = <a data-link-type="grammar" href="#grammardef-serialized-directive" id="ref-for-grammardef-serialized-directive">serialized-directive</a> *( <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc7230#section-3.2.3" id="ref-for-section-3.2.3">OWS</a> ";" [ <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc7230#section-3.2.3" id="ref-for-section-3.2.3①">OWS</a> <a data-link-type="grammar" href="#grammardef-serialized-directive" id="ref-for-grammardef-serialized-directive①">serialized-directive</a> ] )
; <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc7230#section-3.2.3" id="ref-for-section-3.2.3②">OWS</a> is defined in section 3.2.3 of RFC 7230
</pre>
<p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="serialized-csp-list">serialized CSP list</dfn> is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ascii-string" id="ref-for-ascii-string①">ASCII string</a> consisting of a comma-delimited
series of <a data-link-type="dfn" href="#serialized-csp" id="ref-for-serialized-csp">serialized CSPs</a>, adhering to the following ABNF grammar <a data-link-type="biblio" href="#biblio-rfc5234">[RFC5234]</a>:</p>
<pre><dfn data-dfn-type="grammar" data-export="" id="grammardef-serialized-policy-list">serialized-policy-list<a class="self-link" href="#grammardef-serialized-policy-list"></a></dfn> = 1#<a data-link-type="grammar" href="#grammardef-serialized-policy" id="ref-for-grammardef-serialized-policy">serialized-policy</a>
; The '#' rule is defined in section 7 of RFC 7230
</pre>
<h4 class="heading settled algorithm" data-algorithm="Parse a serialized CSP" data-level="2.2.1" id="parse-serialized-policy"><span class="secno">2.2.1. </span><span class="content"> Parse a serialized CSP </span><a class="self-link" href="#parse-serialized-policy"></a></h4>
<p>To <dfn class="dfn-paneled" data-dfn-type="abstract-op" data-export="" id="abstract-opdef-parse-a-serialized-csp">parse a serialized CSP</dfn>, given a <a data-link-type="dfn" href="#serialized-csp" id="ref-for-serialized-csp①">serialized CSP</a> (<var>serialized</var>), a <a data-link-type="dfn" href="#policy-source" id="ref-for-policy-source①">source</a> (<var>source</var>), and a <a data-link-type="dfn" href="#policy-disposition" id="ref-for-policy-disposition">disposition</a> (<var>disposition</var>), execute the
following steps.</p>
<p>This algorithm returns a <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object③">Content Security Policy object</a>. If <var>serialized</var> could not be
parsed, the object’s <a data-link-type="dfn" href="#policy-directive-set" id="ref-for-policy-directive-set">directive set</a> will be empty.</p>
<ol class="algorithm">
<li data-md="">
<p>Let <var>policy</var> be a new <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object④">policy</a> with an empty <a data-link-type="dfn" href="#policy-directive-set" id="ref-for-policy-directive-set①">directive set</a>, a <a data-link-type="dfn" href="#policy-source" id="ref-for-policy-source②">source</a> of <var>source</var>, and a <a data-link-type="dfn" href="#policy-disposition" id="ref-for-policy-disposition①">disposition</a> of <var>disposition</var>.</p>
<li data-md="">
<p>For each <var>token</var> returned by <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#strictly-split" id="ref-for-strictly-split">strictly splitting</a> <var>serialized</var> on
the U+003B SEMICOLON character (<code>;</code>):</p>
<ol>
<li data-md="">
<p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#strip-leading-and-trailing-ascii-whitespace" id="ref-for-strip-leading-and-trailing-ascii-whitespace">Strip leading and trailing ASCII whitespace</a> from <var>token</var>.</p>
<li data-md="">
<p>If <var>token</var> is an empty string, <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue">continue</a>.</p>
<li data-md="">
<p>Let <var>directive name</var> be the result of <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#collect-a-sequence-of-code-points" id="ref-for-collect-a-sequence-of-code-points">collecting a sequence of code points</a> from <var>token</var> which are not <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ascii-whitespace" id="ref-for-ascii-whitespace">ASCII whitespace</a>.</p>
<li data-md="">
<p>If <var>policy</var>’s <a data-link-type="dfn" href="#policy-directive-set" id="ref-for-policy-directive-set②">directive set</a> contains a <a data-link-type="dfn" href="#directives" id="ref-for-directives①">directive</a> whose <a data-link-type="dfn" href="#directive-name" id="ref-for-directive-name">name</a> is <var>directive name</var>, <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue①">continue</a>.</p>
<p>In this case, the user agent SHOULD notify developers that a duplicate directive was
ignored. A console warning might be appropriate, for example.</p>
<li data-md="">
<p>Let <var>directive value</var> be the result of <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#split-on-ascii-whitespace" id="ref-for-split-on-ascii-whitespace">splitting <var>token</var> on
ASCII whitespace</a>.</p>
<li data-md="">
<p>Let <var>directive</var> be a new <a data-link-type="dfn" href="#directives" id="ref-for-directives②">directive</a> whose <a data-link-type="dfn" href="#directive-name" id="ref-for-directive-name①">name</a> is <var>directive name</var>, and <a data-link-type="dfn" href="#directive-value" id="ref-for-directive-value">value</a> is <var>directive value</var>.</p>
<li data-md="">
<p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#set-append" id="ref-for-set-append">Append</a> <var>directive</var> to <var>policy</var>’s <a data-link-type="dfn" href="#policy-directive-set" id="ref-for-policy-directive-set③">directive set</a>.</p>
</ol>
<li data-md="">
<p>Return <var>policy</var>.</p>
</ol>
<h4 class="heading settled algorithm" data-algorithm="Parse a serialized CSP list" data-level="2.2.2" id="parse-serialized-policy-list"><span class="secno">2.2.2. </span><span class="content"> Parse a serialized CSP list </span><a class="self-link" href="#parse-serialized-policy-list"></a></h4>
<p>To <dfn class="dfn-paneled" data-dfn-type="abstract-op" data-export="" id="abstract-opdef-parse-a-serialized-csp-list">parse a serialized CSP list</dfn>, given a <a data-link-type="dfn" href="#serialized-csp-list" id="ref-for-serialized-csp-list">serialized CSP list</a> (<var>list</var>), a <a data-link-type="dfn" href="#policy-source" id="ref-for-policy-source③">source</a> (<var>source</var>), and a <a data-link-type="dfn" href="#policy-disposition" id="ref-for-policy-disposition②">disposition</a> (<var>disposition</var>), execute the following
steps.</p>
<p>This algorithm returns a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list" id="ref-for-list①">list</a> of <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object⑤">Content Security Policy objects</a>. If <var>list</var> cannot be
parsed, the returned list will be empty.</p>
<ol class="algorithm">
<li data-md="">
<p>Let <var>policies</var> be an empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list" id="ref-for-list②">list</a>.</p>
<li data-md="">
<p>For each <var>token</var> returned by <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#split-on-commas" id="ref-for-split-on-commas">splitting <var>list</var> on commas</a>:</p>
<ol>
<li data-md="">
<p>Let <var>policy</var> be the result of <a data-link-type="abstract-op" href="#abstract-opdef-parse-a-serialized-csp" id="ref-for-abstract-opdef-parse-a-serialized-csp">parsing</a> <var>token</var>, with a <a data-link-type="dfn" href="#policy-source" id="ref-for-policy-source④">source</a> of <var>source</var>, and <a data-link-type="dfn" href="#policy-disposition" id="ref-for-policy-disposition③">disposition</a> of <var>disposition</var>.</p>
<li data-md="">
<p>If <var>policy</var>’s <a data-link-type="dfn" href="#policy-directive-set" id="ref-for-policy-directive-set④">directive set</a> is empty, <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue②">continue</a>.</p>
<li data-md="">
<p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list-append" id="ref-for-list-append">Append</a> <var>policy</var> to <var>policies</var>.</p>
</ol>
<li data-md="">
<p>Return <var>policies</var>.</p>
</ol>
<h3 class="heading settled" data-level="2.3" id="framework-directives"><span class="secno">2.3. </span><span class="content">Directives</span><a class="self-link" href="#framework-directives"></a></h3>
<p>Each <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object⑥">policy</a> contains an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-set" id="ref-for-ordered-set①">ordered set</a> of <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="directives">directives</dfn> (its <a data-link-type="dfn" href="#policy-directive-set" id="ref-for-policy-directive-set⑤">directive set</a>), each of which controls a specific behavior. The directives
defined in this document are described in detail in <a href="#csp-directives">§6 Content Security Policy Directives</a>.</p>
<p>Each <a data-link-type="dfn" href="#directives" id="ref-for-directives③">directive</a> is a <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-name">name</dfn> / <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-value">value</dfn> pair. The <a data-link-type="dfn" href="#directive-name" id="ref-for-directive-name②">name</a> is a
non-empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string">string</a>, and the <a data-link-type="dfn" href="#directive-value" id="ref-for-directive-value①">value</a> is a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-set" id="ref-for-ordered-set②">set</a> of non-empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string①">strings</a>. The <a data-link-type="dfn" href="#directive-value" id="ref-for-directive-value②">value</a> MAY be <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list-is-empty" id="ref-for-list-is-empty">empty</a>.</p>
<p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="serialized-directive">serialized directive</dfn> is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ascii-string" id="ref-for-ascii-string②">ASCII string</a>, consisting of one or more
whitespace-delimited tokens, and adhering to the following ABNF <a data-link-type="biblio" href="#biblio-rfc5234">[RFC5234]</a>:</p>
<pre><dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-serialized-directive">serialized-directive</dfn> = <a data-link-type="grammar" href="#grammardef-directive-name" id="ref-for-grammardef-directive-name">directive-name</a> [ <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc7230#section-3.2.3" id="ref-for-section-3.2.3③">RWS</a> <a data-link-type="grammar" href="#grammardef-directive-value" id="ref-for-grammardef-directive-value">directive-value</a> ]
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-directive-name">directive-name</dfn> = 1*( <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1">ALPHA</a> / <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1①">DIGIT</a> / "-" )
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-directive-value">directive-value</dfn> = *( %x09 / %x20-%x2B / %x2D-%x3A / %x3C-%7E )
; Directive values may contain whitespace and <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1②">VCHAR</a> characters,
; excluding ";" and ","
; <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc7230#section-3.2.3" id="ref-for-section-3.2.3④">RWS</a> is defined in section 3.2.3 of RFC7230. <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1③">ALPHA</a>, <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1④">DIGIT</a>, and
; <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1⑤">VCHAR</a> are defined in Appendix B.1 of RFC 5234.
</pre>
<p><a data-link-type="dfn" href="#directives" id="ref-for-directives④">Directives</a> have a number of associated algorithms:</p>
<ol>
<li data-md="">
<p>A <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-pre-request-check">pre-request check</dfn>, which takes a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request" id="ref-for-concept-request">request</a> and a <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object⑦">policy</a> as an argument, and is executed
during <a href="#should-block-request">§4.1.3 Should request be blocked by Content Security Policy?</a>. This algorithm returns "<code>Allowed</code>" unless
otherwise specified.</p>
<li data-md="">
<p>A <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-post-request-check">post-request check</dfn>, which takes a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request" id="ref-for-concept-request①">request</a>, a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response" id="ref-for-concept-response">response</a>, and a <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object⑧">policy</a> as arguments,
and is executed during <a href="#should-block-response">§4.1.4 Should response to request be blocked by Content
Security Policy?</a>. This algorithm returns
"<code>Allowed</code>" unless otherwise specified.</p>
<li data-md="">
<p>A <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-response-check">response check</dfn>, which takes a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request" id="ref-for-concept-request②">request</a>, a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response" id="ref-for-concept-response①">response</a>, and a <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object⑨">policy</a> as arguments,
and is executed during <a href="#should-block-response">§4.1.4 Should response to request be blocked by Content
Security Policy?</a>. This algorithm returns
"<code>Allowed</code>" unless otherwise specified.</p>
<li data-md="">
<p>An <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-inline-check">inline check</dfn>, which takes an <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#element" id="ref-for-element">Element</a></code> a
type string, and a soure string as arguments, and is executed during <a href="#should-block-inline">§4.2.4 Should element’s inline type behavior be blocked by Content Security Policy?</a>. This algorithm returns "<code>Allowed</code>" unless
otherwise specified.</p>
<li data-md="">
<p>An <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-initialization">initialization</dfn>, which takes a <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#document" id="ref-for-document①">Document</a></code> or <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#global-object" id="ref-for-global-object">global object</a>, a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response" id="ref-for-concept-response②">response</a>, and a <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object①⓪">policy</a> as arguments. This algorithm is executed during <a href="#initialize-document-csp">§4.2.1 Initialize a Document's CSP list</a>,
and has no effect unless otherwise specified.</p>
<li data-md="">
<p>A <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-pre-navigation-check">pre-navigation check</dfn>, which takes a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request" id="ref-for-concept-request③">request</a>, type string, and two <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/browsers.html#browsing-context" id="ref-for-browsing-context">browsing contexts</a> as arguments, and
is executed during <a href="#should-block-navigation-request">§4.2.5 Should navigation request of type from source in target be blocked
by Content Security Policy?</a>. It returns
"<code>Allowed</code>" unless otherwise specified.</p>
<li data-md="">
<p>A <dfn class="dfn-paneled" data-dfn-for="directive" data-dfn-type="dfn" data-export="" id="directive-navigation-response-check">navigation response check</dfn>, which takes a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request" id="ref-for-concept-request④">request</a>, a <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response" id="ref-for-concept-response③">response</a> and two <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/browsers.html#browsing-context" id="ref-for-browsing-context①">browsing contexts</a> as
arguments, and is executed during <a href="#should-block-navigation-response">§4.2.6 Should navigation response to navigation request of type from source
in target be blocked by Content Security Policy?</a>.
It returns "<code>Allowed</code>" unless otherwise specified.</p>
</ol>
<h4 class="heading settled" data-level="2.3.1" id="framework-directive-source-list"><span class="secno">2.3.1. </span><span class="content">Source Lists</span><a class="self-link" href="#framework-directive-source-list"></a></h4>
<p>Many <a data-link-type="dfn" href="#directives" id="ref-for-directives⑤">directives</a>' <a data-link-type="dfn" href="#directive-value" id="ref-for-directive-value③">values</a> consist of <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="source-lists">source lists</dfn>: <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-set" id="ref-for-ordered-set③">sets</a> of <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string②">strings</a> which identify content that can be fetched and potentially embedded or
executed. Each <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string③">string</a> represents one of the following types of <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" data-lt="source expression" id="source-expression">source
expression</dfn>:</p>
<ol>
<li data-md="">
<p>Keywords such as <a data-link-type="grammar" href="#grammardef-none" id="ref-for-grammardef-none"><code>'none'</code></a> and <a data-link-type="grammar" href="#grammardef-self" id="ref-for-grammardef-self"><code>'self'</code></a> (which match nothing and the current
URL’s origin, respectively)</p>
<li data-md="">
<p>Serialized URLs such as <code>https://example.com/path/to/file.js</code> (which matches a specific file) or <code>https://example.com/</code> (which matches everything on that origin)</p>
<li data-md="">
<p>Schemes such as <code>https:</code> (which matches any resource having
the specified scheme)</p>
<li data-md="">
<p>Hosts such as <code>example.com</code> (which matches any resource on
the host, regardless of scheme) or <code>*.example.com</code> (which
matches any resource on the host’s subdomains (and any of
its subdomains' subdomains, and so on))</p>
<li data-md="">
<p>Nonces such as <code>'nonce-ch4hvvbHDpv7xCSvXCs3BrNggHdTzxUA'</code> (which can match
specific elements on a page)</p>
<li data-md="">
<p>Digests such as <code>'sha256-abcd...'</code> (which can match specific
elements on a page)</p>
</ol>
<p>A <dfn data-dfn-type="dfn" data-export="" id="serialized-source-list">serialized source list<a class="self-link" href="#serialized-source-list"></a></dfn> is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ascii-string" id="ref-for-ascii-string③">ASCII string</a>, consisting of a
whitespace-delimited series of <a data-link-type="dfn" href="#source-expression" id="ref-for-source-expression①">source expressions</a>, adhering to the following ABNF grammar <a data-link-type="biblio" href="#biblio-rfc5234">[RFC5234]</a>:</p>
<pre><dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-serialized-source-list">serialized-source-list</dfn> = ( <a data-link-type="grammar" href="#grammardef-source-expression" id="ref-for-grammardef-source-expression">source-expression</a> *( <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc7230#section-3.2.3" id="ref-for-section-3.2.3⑤">RWS</a> <a data-link-type="grammar" href="#grammardef-source-expression" id="ref-for-grammardef-source-expression①">source-expression</a> ) ) / "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-none">'none'</dfn>"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-source-expression">source-expression</dfn> = <a data-link-type="grammar" href="#grammardef-scheme-source" id="ref-for-grammardef-scheme-source">scheme-source</a> / <a data-link-type="grammar" href="#grammardef-host-source" id="ref-for-grammardef-host-source">host-source</a> / <a data-link-type="grammar" href="#grammardef-keyword-source" id="ref-for-grammardef-keyword-source">keyword-source</a>
/ <a data-link-type="grammar" href="#grammardef-nonce-source" id="ref-for-grammardef-nonce-source">nonce-source</a> / <a data-link-type="grammar" href="#grammardef-hash-source" id="ref-for-grammardef-hash-source">hash-source</a>
; Schemes: "https:" / "custom-scheme:" / "another.custom-scheme:"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-scheme-source">scheme-source</dfn> = <a data-link-type="grammar" href="#grammardef-scheme-part" id="ref-for-grammardef-scheme-part">scheme-part</a> ":"
; Hosts: "example.com" / "*.example.com" / "https://*.example.com:12/path/to/file.js"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-host-source">host-source</dfn> = [ <a data-link-type="grammar" href="#grammardef-scheme-part" id="ref-for-grammardef-scheme-part①">scheme-part</a> "://" ] <a data-link-type="grammar" href="#grammardef-host-part" id="ref-for-grammardef-host-part">host-part</a> [ ":" <a data-link-type="grammar" href="#grammardef-port-part" id="ref-for-grammardef-port-part">port-part</a> ] [ <a data-link-type="grammar" href="#grammardef-path-part" id="ref-for-grammardef-path-part">path-part</a> ]
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-scheme-part">scheme-part</dfn> = <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc3986#section-3.1" id="ref-for-section-3.1">scheme</a>
; <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc3986#section-3.1" id="ref-for-section-3.1①">scheme</a> is defined in section 3.1 of RFC 3986.
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-host-part">host-part</dfn> = "*" / [ "*." ] 1*<a data-link-type="grammar" href="#grammardef-host-char" id="ref-for-grammardef-host-char">host-char</a> *( "." 1*<a data-link-type="grammar" href="#grammardef-host-char" id="ref-for-grammardef-host-char①">host-char</a> )
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-host-char">host-char</dfn> = <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1⑥">ALPHA</a> / <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1⑦">DIGIT</a> / "-"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-port-part">port-part</dfn> = 1*<a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1⑧">DIGIT</a> / "*"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-path-part">path-part</dfn> = <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc3986#section-3.3" id="ref-for-section-3.3">path-absolute</a>
; <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc3986#section-3.3" id="ref-for-section-3.3①">path-absolute</a> is defined in section 3.3 of RFC 3986.
; Keywords:
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-keyword-source">keyword-source</dfn> = "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-self">'self'</dfn>" / "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-unsafe-inline">'unsafe-inline'</dfn>" / "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-unsafe-eval">'unsafe-eval'</dfn>"
/ "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-strict-dynamic">'strict-dynamic'</dfn>" / "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-unsafe-hashed-attributes">'unsafe-hashed-attributes'</dfn>" /
/ "<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-report-sample">'report-sample'</dfn>"
; Nonces: 'nonce-[nonce goes here]'
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-nonce-source">nonce-source</dfn> = "'nonce-" <a data-link-type="grammar" href="#grammardef-base64-value" id="ref-for-grammardef-base64-value">base64-value</a> "'"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-base64-value">base64-value</dfn> = 1*( <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1⑨">ALPHA</a> / <a data-link-type="grammar" href="https://tools.ietf.org/html/rfc5234#appendix-B.1" id="ref-for-appendix-B.1①⓪">DIGIT</a> / "+" / "/" / "-" / "_" )*2( "=" )
; Digests: 'sha256-[digest goes here]'
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-hash-source">hash-source</dfn> = "'" <a data-link-type="grammar" href="#grammardef-hash-algorithm" id="ref-for-grammardef-hash-algorithm">hash-algorithm</a> "-" <a data-link-type="grammar" href="#grammardef-base64-value" id="ref-for-grammardef-base64-value①">base64-value</a> "'"
<dfn class="dfn-paneled" data-dfn-type="grammar" data-export="" id="grammardef-hash-algorithm">hash-algorithm</dfn> = "sha256" / "sha384" / "sha512"
</pre>
<p>The <a data-link-type="grammar" href="#grammardef-host-char" id="ref-for-grammardef-host-char②">host-char</a> production intentionally contains only ASCII
characters; internationalized domain names cannot be entered directly as part
of a <a data-link-type="dfn" href="#serialized-csp" id="ref-for-serialized-csp②">serialized CSP</a>, but instead MUST be Punycode-encoded <a data-link-type="biblio" href="#biblio-rfc3492">[RFC3492]</a>. For example, the domain <code>üüüüüü.de</code> MUST be represented as <code>xn--tdaaaaaa.de</code>.</p>
<p class="note" role="note"><span>Note:</span> Though IP address do match the grammar above, only <code>127.0.0.1</code> will actually match a URL when used in a source
expression (see <a href="#match-url-to-source-list">§6.6.1.5 Does url match source list in origin with redirect count?</a> for details). The security
properties of IP addresses are suspect, and authors ought to prefer hostnames
whenever possible.</p>
<p class="note" role="note"><span>Note:</span> The <a data-link-type="grammar" href="#grammardef-base64-value" id="ref-for-grammardef-base64-value②">base64-value</a> grammar allows both <a data-link-type="dfn" href="https://tools.ietf.org/html/rfc4648#section-4" id="ref-for-section-4">base64</a> and <a data-link-type="dfn" href="https://tools.ietf.org/html/rfc4648#section-5" id="ref-for-section-5">base64url</a> encoding. These encodings are treated as equivalant when
processing <a data-link-type="grammar" href="#grammardef-hash-source" id="ref-for-grammardef-hash-source①">hash-source</a> values. Nonces, however, are strict string matches:
we use the <a data-link-type="grammar" href="#grammardef-base64-value" id="ref-for-grammardef-base64-value③">base64-value</a> grammar to limit the characters available, and
reduce the complexity for the server-side operator (encodings, etc), but the user agent
doesn’t actually care about any underlying value, nor does it do any decoding of the <a data-link-type="grammar" href="#grammardef-nonce-source" id="ref-for-grammardef-nonce-source①">nonce-source</a> value.</p>
<h3 class="heading settled" data-level="2.4" id="framework-violation"><span class="secno">2.4. </span><span class="content">Violations</span><a class="self-link" href="#framework-violation"></a></h3>
<p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-export="" id="violation">violation</dfn> represents an action or resource which goes against the
set of <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object①①">policy</a> objects associated with a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#global-object" id="ref-for-global-object①">global object</a>.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-global-object">global object</dfn>, which
is the <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#global-object" id="ref-for-global-object②">global object</a> whose <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object①②">policy</a> has been violated.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation①">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-url">url</dfn> which is its <a data-link-type="dfn" href="#violation-global-object" id="ref-for-violation-global-object">global object</a>’s <code class="idl"><a data-link-type="idl" href="https://url.spec.whatwg.org/#url" id="ref-for-url">URL</a></code>.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation②">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-status">status</dfn> which is a
non-negative integer representing the HTTP status code of the resource for
which the global object was instantiated.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation③">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-resource">resource</dfn>, which is
either <code>null</code>, "<code>inline</code>", "<code>eval</code>", or a <code class="idl"><a data-link-type="idl" href="https://url.spec.whatwg.org/#url" id="ref-for-url①">URL</a></code>. It represents the resource
which violated the policy.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation④">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-referrer">referrer</dfn>, which is either <code>null</code>, or a <code class="idl"><a data-link-type="idl" href="https://url.spec.whatwg.org/#url" id="ref-for-url②">URL</a></code>. It represents the referrer of the resource whose policy
was violated.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation⑤">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-policy">policy</dfn>, which is the <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object①③">policy</a> that has been violated.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation⑥">violation</a> has a <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-disposition">disposition</dfn>, which is the <a data-link-type="dfn" href="#policy-disposition" id="ref-for-policy-disposition④">disposition</a> of the <a data-link-type="dfn" href="#content-security-policy-object" id="ref-for-content-security-policy-object①④">policy</a> that has been violated.</p>
<p>Each <a data-link-type="dfn" href="#violation" id="ref-for-violation⑦">violation</a> has an <dfn class="dfn-paneled" data-dfn-for="violation" data-dfn-type="dfn" data-export="" id="violation-effective-directive">effective directive</dfn> which is a non-empty string representing the <a data-link-type="dfn" href="#directives" id="ref-for-directives⑥">directive</a> whose