Re: [TLS] Comments on draft-rescorla-tls-renegotiate
Bodo Moeller <bmoeller@acm.org> Sun, 15 November 2009 19:29 UTC
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From: Bodo Moeller <bmoeller@acm.org>
To: Nicolas Williams <Nicolas.Williams@sun.com>
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Date: Sun, 15 Nov 2009 11:28:57 -0800
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Cc: tls@ietf.org
Subject: Re: [TLS] Comments on draft-rescorla-tls-renegotiate
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On Nov 14, 2009, at 12:31 AM, Nicolas Williams wrote: > On Sat, Nov 14, 2009 at 02:20:56AM +0000, David-Sarah Hopwood wrote: >> Nicolas Williams wrote: >>> Comments: >>> >>> 1) The rest of this comment can be ignored if the use of protocol >>> extensions in draft-rescorla-tls-renegotiate is deemed to not be a >>> problem. >>> >>> [...] >> >> The problem is that this unnecessarily breaks cases in which the >> possibility of attack couldn't have been prevented (because only >> one of the client and server supports the extension), and in which >> there may actually be no attack. > > That's a feature: for how do you know that "there may actually be no > attack"?? In general, you don't -- but sometimes you don't care. TLS is often used for opportunistic encryption (such as between SMTP servers that in many cases have no way to verify each other's certificate): If the client and server can encrypt, they'll do it to get protection at least against passive attackers; otherwise, they'll just fall back to unencrypted transmission. It would be a shame to have protocol negotiation problems make them fall back to unencrypted mode, when the currently deployed protocols could give them the security they expect. Bodo
- [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Marsh Ray
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Marsh Ray
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Florian Weimer
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Michael D'Errico
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Florian Weimer
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- [TLS] TLS or HTTP issue? (was: TLS renegotiation … Nikos Mavrogiannopoulos
- Re: [TLS] TLS renegotiation issue Yngve N. Pettersen (Developer Opera Software ASA)
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Marsh Ray
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Cullen Jennings
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Michael Gray
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS or HTTP issue? Florian Weimer
- Re: [TLS] TLS or HTTP issue? Bruno Harbulot
- Re: [TLS] TLS renegotiation issue Blumenthal, Uri - 0662 - MITLL
- Re: [TLS] TLS or HTTP issue? Peter Saint-Andre
- Re: [TLS] TLS or HTTP issue? Martin Rex
- Re: [TLS] TLS or HTTP issue? (was: TLS renegotiat… Nicolas Williams
- Re: [TLS] TLS or HTTP issue? (was: TLS renegotiat… Nathaniel W Filardo
- Re: [TLS] TLS or HTTP issue? Marsh Ray
- Re: [TLS] TLS or HTTP issue? (was: TLS renegotiat… Nicolas Williams
- [TLS] draft-rescorla-tls-renegotiate.txt Martin Rex
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Michael D'Errico
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Martin Rex
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Martin Rex
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS renegotiation issue Marsh Ray
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Robert Relyea
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Michael D'Errico
- Re: [TLS] TLS or HTTP issue? Dean Anderson
- Re: [TLS] TLS renegotiation issue David Harrington
- [TLS] To API or not (Re: TLS renegotiation issue) Nicolas Williams
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Marsh Ray
- [TLS] Simple way to drop re-negotiation in HTTP (… Nicolas Williams
- Re: [TLS] TLS renegotiation issue Michael D'Errico
- Re: [TLS] TLS renegotiation issue Martin Rex
- Re: [TLS] draft-rescorla-tls-renegotiate.txt Martin Rex
- Re: [TLS] Simple way to drop re-negotiation in HT… Marsh Ray
- Re: [TLS] TLS or HTTP issue? Nikos Mavrogiannopoulos
- Re: [TLS] TLS or HTTP issue? Marsh Ray
- Re: [TLS] TLS renegotiation issue Michael D'Errico
- Re: [TLS] TLS renegotiation issue Marsh Ray
- Re: [TLS] TLS or HTTP issue? Michael D'Errico
- Re: [TLS] Test Server (was TLS renegotiation issu… Michael D'Errico
- Re: [TLS] Test Server (was TLS renegotiation issu… Michael D'Errico
- Re: [TLS] TLS renegotiation issue Nagendra Modadugu
- Re: [TLS] TLS renegotiation issue Eric Rescorla
- Re: [TLS] TLS or HTTP issue? Nicolas Williams
- Re: [TLS] TLS renegotiation issue Nicolas Williams
- Re: [TLS] TLS or HTTP issue? Florian Weimer
- Re: [TLS] Simple way to drop re-negotiation in HT… Nicolas Williams
- Re: [TLS] TLS or HTTP issue? Chris Newman
- Re: [TLS] TLS or HTTP issue? (was: TLS renegotiat… Chris Newman
- Re: [TLS] TLS renegotiation issue Bodo Moeller
- Re: [TLS] TLS or HTTP issue? Nikos Mavrogiannopoulos
- [TLS] Comments on draft-rescorla-tls-renegotiate Nicolas Williams
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… Martin Rex
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… David-Sarah Hopwood
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… David-Sarah Hopwood
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… David-Sarah Hopwood
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… Nicolas Williams
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… Nicolas Williams
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… Nicolas Williams
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… Nelson B Bolyard
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… David-Sarah Hopwood
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… David-Sarah Hopwood
- Re: [TLS] Comments on draft-rescorla-tls-renegoti… Bodo Moeller