Re: [TLS] A not-so crazy idea
Yoav Nir <ynir@checkpoint.com> Sun, 15 November 2009 21:07 UTC
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From: Yoav Nir <ynir@checkpoint.com>
To: Yair Elharrar <Yair.Elharrar@audiocodes.com>, "tls@ietf.org" <tls@ietf.org>
Date: Sun, 15 Nov 2009 23:04:38 +0200
Thread-Topic: [TLS] A not-so crazy idea
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Subject: Re: [TLS] A not-so crazy idea
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That would mean that RFC-compliant clients just don't work. A change like that is fine for a future version, like 1.3, but changing the behavior of 1.0 in a non-compliant way is just wrong. You really have to signal it. Of course, once you have a new version like 1.3, you don't need both old and new behavior. There's jut the new, TLS 1.3 way of calculating the Finished message. ________________________________________ From: tls-bounces@ietf.org [tls-bounces@ietf.org] On Behalf Of Yair Elharrar [Yair.Elharrar@audiocodes.com] Sent: Sunday, November 15, 2009 22:35 To: tls@ietf.org Subject: Re: [TLS] A not-so crazy idea What if we just change the definition of the server's FINISHED message a bit; instead of sending Hash(handshake_msgs) to the client, the server will send Hash(handshake_msgs || verify_data) using the session's previous verify_data. There's no change to initial handshakes, of course, as there's no previous verify_data. This means: 1. Patched client and patched server: renegotiation is safe. 2. Patched client, unpatched server: the client can calculate Hash(handshake_msgs) and tell that the server is unpatched. It is up to the client to decide whether to abort the session or not. 3. Unpatched client, patched server: renegotiation will fail, as it should. Yair --
- Re: [TLS] TLSrenego - possibilities, suggestion f… Marsh Ray
- Re: [TLS] TLSrenego - current summary of semantic… Pasi.Eronen
- [TLS] assert TLSext in renego-ServerHello instead… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] assert TLSext in renego-ServerHello ins… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Eric Rescorla
- Re: [TLS] assert TLSext in renego-ServerHello ins… David-Sarah Hopwood
- Re: [TLS] assert TLSext in renego-ServerHello ins… Michael D'Errico
- Re: [TLS] assert TLSext in renego-ServerHello ins… David-Sarah Hopwood
- Re: [TLS] assert TLSext in renego-ServerHello ins… David-Sarah Hopwood
- Re: [TLS] assert TLSext in renego-ServerHello ins… Michael D'Errico
- Re: [TLS] assert TLSext in renego-ServerHello ins… David-Sarah Hopwood
- Re: [TLS] assert TLSext in renego-ServerHello ins… David-Sarah Hopwood
- Re: [TLS] assert TLSext in renego-ServerHello ins… Eric Rescorla
- Re: [TLS] assert TLSext in renego-ServerHello ins… Eric Rescorla
- Re: [TLS] assert TLSext in renego-ServerHello ins… Michael D'Errico
- [TLS] TLSrenego - current summary of semantics an… Martin Rex
- Re: [TLS] TLSrenego - current summary of semantic… Steve Dispensa
- Re: [TLS] TLSrenego - current summary of semantic… Nicolas Williams
- Re: [TLS] TLSrenego - current summary of semantic… Yair Elharrar
- Re: [TLS] TLSrenego - current summary of semantic… Michael D'Errico
- Re: [TLS] TLSrenego - current summary of semantic… Marsh Ray
- Re: [TLS] TLSrenego - current summary of semantic… Nicolas Williams
- Re: [TLS] TLSrenego - current summary of semantic… Martin Rex
- Re: [TLS] TLSrenego - current summary of semantic… Michael D'Errico
- Re: [TLS] TLSrenego - current summary of semantic… Martin Rex
- Re: [TLS] TLSrenego - current summary of semantic… Michael D'Errico
- Re: [TLS] TLSrenego - possibilities, suggestion f… Martin Rex
- Re: [TLS] TLSrenego - possibilities, suggestion f… Yair Elharrar
- Re: [TLS] TLSrenego - possibilities, suggestion f… Marsh Ray
- Re: [TLS] TLSrenego - possibilities, suggestion f… Martin Rex
- Re: [TLS] TLSrenego - possibilities, suggestion f… Yair Elharrar
- Re: [TLS] TLSrenego - possibilities, suggestion f… Martin Rex
- Re: [TLS] TLSrenego - possibilities, suggestion f… Rob P Williams
- Re: [TLS] TLSrenego - possibilities, suggestion f… Yoav Nir
- Re: [TLS] TLSrenego - possibilities, suggestion f… Marsh Ray
- Re: [TLS] TLSrenego - possibilities, suggestion f… Marsh Ray
- Re: [TLS] TLSrenego - possibilities, suggestion f… Rob P Williams
- Re: [TLS] TLSrenego - possibilities, suggestion f… Michael D'Errico
- Re: [TLS] TLSrenego - possibilities, suggestion f… Peter Gutmann
- Re: [TLS] TLSrenego - possibilities, suggestion f… Yoav Nir
- Re: [TLS] TLSrenego - possibilities, suggestion f… Peter Gutmann
- Re: [TLS] TLSrenego - possibilities, suggestion f… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Eric Rescorla
- Re: [TLS] History of extensions Marsh Ray
- Re: [TLS] History of extensions Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Michael D'Errico
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] History of extensions Nicolas Williams
- Re: [TLS] History of extensions Martin Rex
- Re: [TLS] History of extensions Nicolas Williams
- Re: [TLS] assert TLSext in renego-ServerHello ins… Eric Rescorla
- Re: [TLS] History of extensions Eric Rescorla
- [TLS] Protected Renegotiation -- refined proposal Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Michael D'Errico
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] Protected Renegotiation -- refined prop… Martin Rex
- Re: [TLS] History of extensions Nicolas Williams
- Re: [TLS] TLSrenego - possibilities, suggestion f… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Yoav Nir
- Re: [TLS] assert TLSext in renego-ServerHello ins… Dr Stephen Henson
- Re: [TLS] History of extensions Eric Rescorla
- Re: [TLS] TLSrenego - possibilities, suggestion f… Martin Rex
- Re: [TLS] Protected Renegotiation -- refined prop… Eric Rescorla
- Re: [TLS] History of extensions Nicolas Williams
- Re: [TLS] History of extensions Eric Rescorla
- Re: [TLS] History of extensions Nicolas Williams
- Re: [TLS] TLSrenego - possibilities, suggestion f… Nasko Oskov
- Re: [TLS] History of extensions Eric Rescorla
- [TLS] Redefine Finished message for TLS 1.3 ? Nelson B Bolyard
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Nicolas Williams
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Nelson B Bolyard
- Re: [TLS] Redefine Finished message for TLS 1.3 ? David-Sarah Hopwood
- Re: [TLS] History of extensions Martin Rex
- Re: [TLS] Protected Renegotiation -- refined prop… Martin Rex
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Nicolas Williams
- Re: [TLS] History of extensions Martin Rex
- Re: [TLS] History of extensions David-Sarah Hopwood
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Martin Rex
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Michael D'Errico
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Marsh Ray
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Martin Rex
- Re: [TLS] Redefine Finished message for TLS 1.3 ? David-Sarah Hopwood
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Marsh Ray
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Martin Rex
- [TLS] A crazy idea Michael D'Errico
- Re: [TLS] A crazy idea Marsh Ray
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Nelson B Bolyard
- Re: [TLS] A crazy idea Michael D'Errico
- Re: [TLS] Protected Renegotiation -- refined prop… Yoav Nir
- Re: [TLS] A crazy idea Nicolas Williams
- Re: [TLS] TLSrenego - possibilities, suggestion f… Bodo Moeller
- Re: [TLS] TLSrenego - possibilities, suggestion f… Marsh Ray
- Re: [TLS] TLSrenego - possibilities, suggestion f… Joseph Salowey (jsalowey)
- Re: [TLS] A not-so crazy idea Michael D'Errico
- Re: [TLS] TLSrenego - possibilities, suggestion f… Bodo Moeller
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Bodo Moeller
- Re: [TLS] TLSrenego - possibilities, suggestion f… Marsh Ray
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Bodo Moeller
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Bodo Moeller
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] A not-so crazy idea Nicolas Williams
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Bodo Moeller
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] assert TLSext in renego-ServerHello ins… Bodo Moeller
- Re: [TLS] A not-so crazy idea Yair Elharrar
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] assert TLSext in renego-ServerHello ins… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Marsh Ray
- Re: [TLS] A not-so crazy idea Yoav Nir
- Re: [TLS] assert TLSext in renego-ServerHello ins… Nelson B Bolyard
- Re: [TLS] assert TLSext in renego-ServerHello ins… Bodo Moeller
- Re: [TLS] assert TLSext in renego-ServerHello ins… Eric Rescorla
- Re: [TLS] assert TLSext in renego-ServerHello ins… Martin Rex
- Re: [TLS] assert TLSext in renego-ServerHello ins… Bodo Moeller
- Re: [TLS] Redefine Finished message for TLS 1.3 ? Nelson Bolyard