Re: [TLS] Questions about TLS Server Name Indication extension

Wan-Teh Chang <wtc@google.com> Thu, 29 October 2009 00:51 UTC

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Date: Wed, 28 Oct 2009 17:52:04 -0700
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From: Wan-Teh Chang <wtc@google.com>
To: Nelson B Bolyard <nelson@bolyard.me>
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Cc: Alexei.Volkov@sun.com, tls@ietf.org
Subject: Re: [TLS] Questions about TLS Server Name Indication extension
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On Wed, Oct 28, 2009 at 4:26 PM, Nelson B Bolyard <nelson@bolyard.me> wrote:
>
> Consider this scenario:
> Physical host has two virtual hosts, A and B.
> First handshake:
>  client sends SNI with host name A, empty session ID.
>  server does full handshake, session ID 1.
> Second handshake (renegotiation):
>  client sends SNI with host name B and session ID 1,

I think "renegotiation" should be "resumption".

In this case, the client should not request a resumption
handshake with session ID 1, because the server won't
send a certificate in a resumption handshake, so the
client cannot verify the server has a certificate for host
name B.

The only exception is that the certificate for host name A
has a subject alternative name for host name B.

Wan-Teh