Re: [TLS] Review of PR #209

Ilari Liusvaara <ilari.liusvaara@elisanet.fi> Mon, 21 September 2015 14:02 UTC

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Date: Mon, 21 Sep 2015 17:02:35 +0300
From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
To: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>
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Subject: Re: [TLS] Review of PR #209
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On Mon, Sep 21, 2015 at 07:38:45AM +0200, Karthikeyan Bhargavan wrote:
> 
> In other words, if we do allow this change to client authentication,
> to be safe, we must analyze the resulting protocol *as if*
> applications will use the authentication event to attest to all data,
> past and present, that may be associated with the data in the current
> connection.

Under such assumption, even dynamic reauth in HTTP/1.1 is unsafe. If
one additionally assumes causality, dynamic reauth in non-pipelined
HTTP/1.1 may be safe, but dynamic reauth in HTTP/2 (or HTTP/1.1 with
pipelining) is still unsafe.


-Ilari