[Top] [All Lists]

Re: [ietf-smtp] FWD: [Technical Errata Reported] RFC5321 (5414)

2018-06-30 14:29:57

--On Saturday, June 30, 2018 21:06 +0200 Arnt Gulbrandsen
<arnt(_at_)gulbrandsen(_dot_)priv(_dot_)no> wrote:

I seem to remember that someone actually uses this... for
double bounces? From: ""@[] or an address target like that.

Qmail, perhaps, but I am fairly sure I have seen two users.

Strikes me today as terminally ugly; what I can't remember is
whether we decided to allow it.  It wouldn't be the only thing
that Qmail does that we decided to continue to disallow.  Put
differently, I personally think allowing this is dumb and
looking for trouble, but it is not clear that it is an error
rather than an intentional decision.

If we did decide to allow this, it goes back to 2821 and DRUMS,
which has

      Quoted-string = DQUOTE *qcontent DQUOTE

qcontent is defined for 2821 in 2822 with (order reversed for

  qcontent  =       qtext / quoted-pair

  qtext  = NO-WS-CTL /    ; Non white space controls

            %d33 /        ; The rest of the US-ASCII
            %d35-91 /     ;  characters not including "\"
            %d93-126      ;  or the quote character

NO-WS-CTL = %d1-8 /       ; US-ASCII control characters
            %d11 /        ;  that do not include the
            %d12 /        ;  carriage return, line feed,
            %d14-31 /     ;  and white space characters

So I think 2821 allows 

Anyone else remember?


ietf-smtp mailing list