Re: [TLS] Server Signature Algorithms
Wan-Teh Chang <wtc@google.com> Mon, 02 November 2009 18:02 UTC
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Date: Mon, 02 Nov 2009 10:02:41 -0800
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From: Wan-Teh Chang <wtc@google.com>
To: Michael D'Errico <mike-list@pobox.com>, Nikos Mavrogiannopoulos <nmav@gnutls.org>
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Cc: tls@ietf.org
Subject: Re: [TLS] Server Signature Algorithms
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On Sun, Nov 1, 2009 at 1:34 PM, Michael D'Errico <mike-list@pobox.com> wrote: > So instead of changing the existing signature_algorithms extension, > nothing would break by creating a new server_signature_algorithms > extension. Client support would be advertised by sending an empty > extension to the server. The server would show support by replying > with its list. Michael: I agree this would be the safest solution which eliminates the concern of breaking some TLS 1.2 implementation, at the cost of adding a new TLS extension. This would be an example of a "server-oriented" extension described in Sec. 2.3, page 7 of RFC 4366. Nikos: GnuTLS is one of the first TLS 1.2 implementations. How does GnuTLS deal with this issue now? Does it compute hashes of all the hash algorithms it supports on the handshake messages, or does it buffer the handshake messages until the hash algorithm has been selected? Wan-Teh
- [TLS] Server Signature Algorithms Michael D'Errico
- Re: [TLS] Server Signature Algorithms Michael D'Errico
- Re: [TLS] Server Signature Algorithms Nikos Mavrogiannopoulos
- Re: [TLS] Server Signature Algorithms Michael Gray
- Re: [TLS] Server Signature Algorithms Michael D'Errico
- Re: [TLS] Server Signature Algorithms Martin Rex
- Re: [TLS] Server Signature Algorithms Wan-Teh Chang
- Re: [TLS] Server Signature Algorithms Nikos Mavrogiannopoulos