Re: BATV breaks rfc2821bis?

Paul Smith wrote:
> mouss wrote:
> > > That's fine, as it doesn't seem that the remote server is supposed to 
> > > gain any benefit. It's the spoofed domain's MTAs which can gain the 
> > > benefit.
> > but then why standardize the format? anybody can use "internal 
> > aliases" of any form (aka disposable addresses).
> That's my view as well. A standard return path syntax (eg 
> 'batv=<key>=<orig-local-part>@<domain>') is a good idea as it allows the 
> original local part to be extracted if necessary, but beyond that, 
> there's no point to a standard format for private keys.
"Extracting the local part" is obviously an interpretation of the 
local-part, which would break section 2.3.11 of 2821bis, as SM 
noticed. I don't recall anything in the standard that deprecates equal 
signs in the local-part.
Section 4.1.1.2 additionally states that "The reverse-path consists of 
the sender mailbox", not a variation thereof. That wording apparently 
bans using time-varying tags, unless we reinterpret BATV as a 
redistribution service for ephemeral ad-hoc lists, in the sense of 
section 3.9.2 (but beware poor subscription policies.) A rather 
cumbersome way to standardize things.