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Re: [Wpack] On double-hashing (was: Re: About content-based origins)

Devin Mullins <twifkak@google.com> Fri, 27 March 2020 20:06 UTC

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From: Devin Mullins <twifkak@google.com>
Date: Fri, 27 Mar 2020 13:06:29 -0700
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To: Martin Thomson <mt@lowentropy.net>
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Subject: Re: [Wpack] On double-hashing (was: Re: About content-based origins)
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On Thu, Mar 26, 2020 at 9:32 PM Martin Thomson <mt@lowentropy.net> wrote:

> Slowly crawling out from a giant pile of email...
>

No worries, understood; my life is a giant pile of email.


> without it being susceptible to making mistakes ... if the bundle and
> origin want to collude I am of the opinion that that is fine


Ah, good to know. To clarify: Am I right in assuming my above proposed
attack is somewhere on the spectrum of
https://github.com/WICG/webpackage/pull/424 ? That is, it requires
publisher server-side work, but is a potential end-run around mitigations
to backchannel sharing such as per-origin IP obfuscation and fingerprint
entropy reduction. If so, then what motivates
https://github.com/martinthomson/wpack-content/issues/1 ?

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