Bug 171248 – importScripts() should respect X-Content-Type-Options: nosniff

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Daniel Bates]

Fetching a worker-imported script should respect the X-Content-Type-Options: nosniff header as such a fetch is ultimately a "main fetch" and according to "main fetch":

[[
17. If response is not a network error and any of the following algorithms returns blocked, then set response and internalResponse to a network error:

...
should internalResponse to request be blocked due to no sniff
]]
<https://fetch.spec.whatwg.org/#main-fetch> (30 March 2017)

This functionality is exercised by the Web Platform Test <https://trac.webkit.org/browser/trunk/LayoutTests/imported/w3c/web-platform-tests/fetch/nosniff/importscripts.html?rev=200195>.

[Radar WebKit Bug Importer]

<rdar://problem/31819023>

[Daniel Bates]

Created attachment 308957 [details]
Patch

[Andy Estes]

Comment on attachment 308957 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=308957&action=review

> Source/WebCore/workers/WorkerScriptLoader.cpp:2
> + * Copyright (C) 2009, 2017 Apple Inc. All Rights Reserved.

2009-2017

> Source/WebCore/workers/WorkerScriptLoader.cpp:119
> +    String mimeType = extractMIMETypeFromMediaType(response.httpHeaderField(HTTPHeaderName::ContentType)).convertToASCIILowercase();

Do you need to convert to ASCII lowercase here? MIMETypeRegistry does case-insensitive comparisons.

[Daniel Bates]

(In reply to Andy Estes from comment #3)
> Comment on attachment 308957 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=308957&action=review
> 
> > Source/WebCore/workers/WorkerScriptLoader.cpp:2
> > + * Copyright (C) 2009, 2017 Apple Inc. All Rights Reserved.
> 
> 2009-2017
> 

Will fix.

> > Source/WebCore/workers/WorkerScriptLoader.cpp:119
> > +    String mimeType = extractMIMETypeFromMediaType(response.httpHeaderField(HTTPHeaderName::ContentType)).convertToASCIILowercase();
> 
> Do you need to convert to ASCII lowercase here? MIMETypeRegistry does
> case-insensitive comparisons.

You're right! No need to convert to lowercase as MIMETypeRegistry does the lookup case-insensitively. Will fix before landing.

[Daniel Bates]

Committed r216195: <http://trac.webkit.org/changeset/216195>