Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv
mrex@sap.com (Martin Rex) Thu, 04 December 2014 02:16 UTC
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To: Brian Smith <brian@briansmith.org>
Date: Thu, 04 Dec 2014 03:16:47 +0100
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From: mrex@sap.com
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Cc: "TLS@ietf.org (tls@ietf.org)" <tls@ietf.org>
Subject: Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv
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Brian Smith wrote: > Sean Turner <turners@ieca.com> wrote: >> This message initiates the 2nd WGLC for draft-ietf-tls-downgrade-scsv-02. >> Please review the document and send your comments to the list by Friday, >> December 12, 2014. > > The text in the draft should be changed to read something like > "Clients SHOULD put the TLS_FALLBACK_SCSV after all cipher suites that > the client actually intends to negotiate." That is silly. I don't think there is such a weird recommendation in rfc5746. > > Recently, it has been shown that it is problematic to put the > TLS_FALLBACK_SCSV cipher suite ahead of any real cipher suites in the > ClientHello, because doing so causes unintended handshake failures. This statement is self-contradictory. The entire and only purpose of this I-D is to cause handshake failures, which is why this entire proposal is currently totally bogus. Should I ever make any changes to a server in response to this document, then it will be continuing the handshake with ServerHello.server_version = { 3, 1 } if it appears in a ClientHello with ClientHello.client_version = { 3, 0 } plus a configuration setting to keep the server igoring the fallback scsv entirely. -Martin
- [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Sean Turner
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Bodo Moeller
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Brian Smith
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Martin Thomson
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Martin Rex
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Brian Smith
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Bodo Moeller
- Re: [TLS] 2nd WGLC: draft-ietf-tls-downgrade-scsv Bodo Moeller