Eric Rescorla wrote: > draft-ietf-tls-ecdhe-psk-aead-04: Discuss > > ---------------------------------------------------------------------- > DISCUSS: > ---------------------------------------------------------------------- > > The following text appears to have been added in -04 > > A server receiving a ClientHello and a client_version indicating > (3,1) "TLS 1.0" or (3,2) "TLS 1.1" and any of the cipher suites from > this document in ClientHello.cipher_suites can safely assume that > the > client supports TLS 1.2 and is willing to use it. The server MUST > NOT negotiate these cipher suites with TLS protocol versions earlier > than TLS 1.2. Not requiring clients to indicate their support for > TLS 1.2 cipher suites exclusively through ClientHello.client_hello > improves the interoperability in the installed base and use of TLS > 1.2 AEAD cipher suites without upsetting the installed base of > version-intolerant TLS servers, results in more TLS handshakes > succeeding and obviates fallback mechanisms. > > This is a major technical change from -03, which, AFAIK, prohibited > the server from negotiating these algorithms with TLS 1.1 and below > and maintained the usual TLS version 1.2 negotiation rules.
This change _still_ prohibits the server from negotiating these algorithms with TLSv1.1 and below. Could you elaborate a little on where and why you see a problem with this? As this changes tries to explain, had such a text been used for all TLSv1.2 AEAD cipher suite code points, then browsers would have never needed any "downgrade dance" fallbacks, POODLE would have never existed as a browser problem, and the TLS_FALLBACK_SCSV band-aid would not been needed, either. -Martin _______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
