In article <[email protected]> you write: >> While the Domain part of that ABNF doesn't describe how it's supposed >> to be derived from "Information derived by server from TCP connection" >> for the BY clause specifically, i think using it for SNI is entirely >> reasonable. > >That seems like a layering violation to me. I would think that the >information about the TCP connection would consist of the IPs and ports. > It seems to me like anything TLS related would be at a higher layer >than "the TCP connection".
The syntax of the Received header was defined in RFC 2821 in 2001 and copied verbatim into 5321. STARTTLS was added by RFC 3207 in 2002, and SNI was added to TLS by RFC 3546 in 2003.* When the ABNF about extended-domain was written with the comment about info derived from the TCP connection, the TCP connection was synonymous with the transport. Now the transport is TCP plus STARTTLS in various versions plus SNI, none of which was contemplated back in 2001. I think it's reasonable to use extended-domain for info about the underlying transport, even if the details are not strictly about TCP. After all, the rDNS name in the FROM extended-domain comes from a DNS PTR lookup of the IP address which uses IP over UDP so it's never been strictly about TCP. R's, John * I spent five minutes looking this history up so as not to waste other people's time. It's not hard. _______________________________________________ Uta mailing list [email protected] https://www.ietf.org/mailman/listinfo/uta
