Re: [TLS] draft-ietf-tls-curve25519-01: Is public key validation necessary or helpful?
Adam Langley <agl@imperialviolet.org> Thu, 31 December 2015 03:30 UTC
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Date: Wed, 30 Dec 2015 19:30:08 -0800
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From: Adam Langley <agl@imperialviolet.org>
To: Brian Smith <brian@briansmith.org>
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Cc: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>, "<tls@ietf.org>" <tls@ietf.org>
Subject: Re: [TLS] draft-ietf-tls-curve25519-01: Is public key validation necessary or helpful?
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On Wed, Dec 30, 2015 at 4:03 PM, Brian Smith <brian@briansmith.org> wrote: > I think it is a good idea to implement the session hash extension, in > general. However, I think it is a bad idea to prescribe it as the solution > for this particular problem because: > > 1. draft-irtf-cfrg-curves-11, in sections 6.1 and section 6.2 already > require the check for a non-zero result, and that check is sufficient. As discussed on the CFRG list, the plan is that the final curves RFC will say that the zero check is a MAY. (See https://www.ietf.org/mail-archive/web/cfrg/current/msg07611.html) I don't mind if the integration of curve25519 in TLS requires a zero-check or not, but what property are people hoping to gain? If one wants to avoid triple-handshake like issues then session-hash is the answer. A client can use an RSA key exchange to control the PMS completely, of course, and, with finite-field DH, a value of zero or p-1 will usually allow the same. Cheers AGL
- [TLS] draft-ietf-tls-curve25519-01: Is public key… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Watson Ladd
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Martin Thomson
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Martin Thomson
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Viktor Dukhovni
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Martin Thomson
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Karthikeyan Bhargavan
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Kurt Roeckx
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Martin Thomson
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Watson Ladd
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Eric Rescorla
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Watson Ladd
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Adam Langley
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Brian Smith
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Alyssa Rowan
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Jeffrey Walton
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Eric Rescorla
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Adam Langley
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Eric Rescorla
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Martin Thomson
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Blumenthal, Uri - 0553 - MITLL
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Eric Rescorla
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Eric Rescorla
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- [TLS] TCP Keep Alive Question: draft-ietf-tls-tls… nalini.elkins
- Re: [TLS] TCP Keep Alive Question: draft-ietf-tls… Watson Ladd
- Re: [TLS] TCP Keep Alive Question: draft-ietf-tls… nalini.elkins
- Re: [TLS] TCP Keep Alive Question: draft-ietf-tls… Roland Zink
- Re: [TLS] TCP Keep Alive Question: draft-ietf-tls… nalini.elkins
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Ilari Liusvaara
- Re: [TLS] draft-ietf-tls-curve25519-01: Is public… Watson Ladd