Re: [TLS] prohibit <1.2 support on 1.3+ servers (but allow clients)
mrex@sap.com (Martin Rex) Fri, 22 May 2015 07:42 UTC
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To: Dave Garrett <davemgarrett@gmail.com>
Date: Fri, 22 May 2015 09:42:40 +0200
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From: mrex@sap.com
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Cc: "maray@microsoft.com" <maray@microsoft.com>, "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] prohibit <1.2 support on 1.3+ servers (but allow clients)
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Dave Garrett wrote: > On Thursday, May 21, 2015 07:09:42 pm Yoav Nir wrote: >> Then point at the BCP. Only problem is that it doesn?t say what you want >> it to say (it allows TLS 1.0 when the client does not support anything else) > > In my first post I said that I don't propose changing anything for existing > deployments. The BCP is currently a "SHOULD NOT" for current TLS. > I'm proposing a "MUST NOT" for TLS 1.3+ implementations only. > > The BCP is also not directly part of the TLS spec. What I'm suggesting is > considering 1.0/1.1 to be not legitimate forever, not just not "best". All current "recommendations" against TLSv1.0 and TLSv1.1 are well-known FUD. The difference between TLSv1.0 with 1/(n-1) record splitting and TLSv1.1 is cryptographically insignificant and the security of TLSv1.2 is lower than both of its precedessors (e.g. throug the botched TLS signature extension and the dumb idea to replace the md5+sha1 signatures with sha1-only signatures for RSA certificates. For the mandatory to implement TLSv1.2 cipher suite, TLSv1.0 and TLSv1.1 are just fine. AEAD cipher suites are not part of TLSv1.2, they're a mere optional add-on that is artificially limited to TLSv1.2, and a number of TLSv1.2 implementations do not support AEAD cipher suites. Same for Elliptic Curve. It's optional, and to date, it is not even standards track. Many TLS implementations do implement EC. -Martin
- [TLS] prohibit <1.2 support on 1.3+ servers (but … Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Loganaden Velvindron
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Yoav Nir
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Thijs van Dijk
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Jeffrey Walton
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Kurt Roeckx
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Yuhong Bao
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Yoav Nir
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Yoav Nir
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Watson Ladd
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Yoav Nir
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Yoav Nir
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Martin Rex
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Martin Thomson
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Aaron Zauner
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Tony Arcieri
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Martin Thomson
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Aaron Zauner
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Martin Thomson
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Tony Arcieri
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Xiaoyin Liu
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Dave Garrett
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Martin Rex
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Hubert Kario
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Peter Gutmann
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Xiaoyin Liu
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Salz, Rich
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Salz, Rich
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Ronald del Rosario
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Dave Garrett
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Dave Garrett
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Geoffrey Keating
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Tony Arcieri
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Jeffrey Walton
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Bill Frantz
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Peter Gutmann
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Geoff Keating
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Jeffrey Walton
- Re: [TLS] prohibit <1.2 support on 1.3+ servers (… Florian Weimer
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Yuhong Bao
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Martin Thomson
- Re: [TLS] prohibit <1.2 on clients (but allow ser… Salz, Rich