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Bug 17816 - appcache: Prevent sensitive data from being cached
Summary: appcache: Prevent sensitive data from being cached
Status: RESOLVED WONTFIX
Alias: None
Product: WHATWG
Classification: Unclassified
Component: HTML (show other bugs)
Version: unspecified
Hardware: Other other
: P3 normal
Target Milestone: Unsorted
Assignee: Ian 'Hixie' Hickson
QA Contact: contributor
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2012-07-18 06:54 UTC by contributor
Modified: 2012-10-12 19:01 UTC (History)
3 users (show)

See Also:


Attachments

Description contributor 2012-07-18 06:54:20 UTC
This was was cloned from bug 15700 as part of operation convergence.
Originally filed: 2012-01-24 22:23:00 +0000
Original reporter: Tobie Langel <tobie.langel@gmail.com>

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 #0   Tobie Langel                                    2012-01-24 22:23:11 +0000 
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Currently, the editor's draft allows preventing content from being cached by using the no-store http header. Often, developers cannot or do not know how to modify http headers to block sensitive parts of a website from being cached (when visited) by AppCache. e.g.:

A website containing both public and sensitive HTML pages needs to be made available offline. The sensitive data must not be stored on the device. The website is hosted on a virtual host and HTTP headers cannot be modified. The web developer can prevent such pages from being cached by specifying them directly in the manifest.
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 #1   Ian 'Hixie' Hickson                             2012-01-31 23:24:05 +0000 
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Why would any pages be cached if they're not listed in the manifest?

Also, who on earth is dealing with sensitive data yet can't change caching headers? That's a frightening thought.
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 #2   Tobie Langel                                    2012-03-27 14:16:09 +0000 
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They'd be cached as master entries simply by being visited.
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Comment 1 Ian 'Hixie' Hickson 2012-09-26 18:20:06 UTC
A file is only going to end up cached as a master entry if it's got a manifest="" attribute, no?
Comment 2 Ian 'Hixie' Hickson 2012-10-11 21:23:30 UTC
I don't really understand the problem here. The only files that are going to get cached are the ones the author opts to have cached, either by setting a manifest="" attribute, or by putting them in the manifest. Even in browsers that don't have manifest support, if you go to a page, it'll get cached unless you have headers set to avoid caching. So if you don't want caching, you need to update headers, that's got nothing to do with appcache. Updating headers for caching is much simpler to do than other things you have to do when dealing with sensitive data, so I don't understand who would have a problem here.
Comment 3 Ian 'Hixie' Hickson 2012-10-11 21:25:18 UTC
Tobie: Please reopen this bug if you can provide the information needed. Thanks.
Comment 4 Tobie Langel 2012-10-11 21:30:57 UTC
The requirement here was to be able to prevent caching the master entry, while caching the sub-resources.
Comment 5 Ian 'Hixie' Hickson 2012-10-12 19:01:44 UTC
That would be pointless. It would literally mean you got no benefit from appcache whatsoever beyond just normal HTTP caching.