Re: [TLS] MITM Attacks on Client Authentication after Resumption

mrex@sap.com (Martin Rex) Wed, 05 March 2014 13:41 UTC

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To: Karthik Bhargavan <karthik.bhargavan@gmail.com>
Date: Wed, 5 Mar 2014 14:40:53 +0100 (CET)
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From: mrex@sap.com (Martin Rex)
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Subject: Re: [TLS] MITM Attacks on Client Authentication after Resumption
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Karthik Bhargavan wrote:
> > The only "non-static" data covered by the Finished handshake messages of
> > the abbbreviated TLS handshake (i.e. that goes into the renegotiation_info
> > of the resumed TLS handshake are):
> >
> >     ClientHello.random
> >     ServerHello.random
> >     ClientHello.session_id == ServerHello.session_id
> >
> 
> Renego Indication uses the client and server verify data:
> 
> verify_data = PRF(master_secret, label, Hash(handshake_message)
> 
> So, it is bound to the master_secret

*Blush*

You're correct.  I'm sorry for the confusion.

-Martin