[TLS] Proposal for detecting fraudulent certificates

Florian Weimer <fweimer@bfk.de> Mon, 26 September 2011 14:27 UTC

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From: Florian Weimer <fweimer@bfk.de>
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Date: Mon, 26 Sep 2011 14:29:49 +0000
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Subject: [TLS] Proposal for detecting fraudulent certificates
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I have submitted draft-weimer-tls-previous-certificate-00, which intents
to facilitate detection of fraudulent certificates used in the wild:

<http://tools.ietf.org/html/draft-weimer-tls-previous-certificate-00>

The basic idea is to use leaks from mobile clients moving between
networks with and without a clear path to the server.  The previous
server certificate chain is included in the client hello, so the server
receives it when the client transitions to a network with a clear path.

This draft prompted my previous question about extension size limits.
Unfortunately, that issue makes this very simple idea somewhat
complicated, but I tried to add a fairly straightforward workaround.

-- 
Florian Weimer                <fweimer@bfk.de>;
BFK edv-consulting GmbH       http://www.bfk.de/
Kriegsstra├če 100              tel: +49-721-96201-1
D-76133 Karlsruhe             fax: +49-721-96201-99