On Wed, 18 Mar 1998 16:35:39 -0800, Michael Helm
<helm(_at_)fionn(_dot_)es(_dot_)net>
wrote:
Christopher Lindsey writes:
:0:
* !^Message-Id:[\t ]+<("[^"]+"|[^ <>@]+)@[^<>]*>$
^^^^^^^^^^^^^^^^^
Is this compliant yet? I'm not sure it's liberal enuf about
what's left of "@" compared to the spec. For example,
Try this (not sure if it's up to spec either, I just fixed what I
thought was obviously wrong with the above):
:0:
* ! ^Message-Id:[ ]*<("[^"]*"|[^ <>@"]+)+(_at_)[^<>@ ]+>[ ]*$
no-valid-msgid
This passes through
Message-Id: <"OP-MIME expo400:439*""
<allanm(_at_)op(_dot_)x400(_dot_)icl(_dot_)co(_dot_)uk>"@MHS>
but traps out
Message-ID: <M10250103.005.z2j35.1.980317164507Z
.CC-MAIL*/O=HQ/PRMD=USDOE/ADMD=ATTMAIL/C=US
/@MHS>
Just to highlight my changes:
* Change :[\t ]+ to :[ ]* (\t is not valid in Procmail but I
take it Chris is using it in a pseudocode fashion)
* Permit empty pair of quotes (is this legal?)
* Allow iterations over [pseudocode] (".*"|[^"]+) with a +
(I take it the localpart can't be empty)
* Disallow spaces and tabs after @ and require at least one char
* Permit whitespace after closing broket
Can't there be backslash-escaped quotes inside double-quoted strings?
Any other problems?
Your point is well taken, it's clear message-id checks have to
be part of a scoring mechanism for spam control. I'd like to
just trap non-conforming ones & not try to enumerate all the
spam special cases (espec since they probably have a limited
lifetime). Or perhaps combine them (if it's non-conforming
and fits this other pattern, it's Spam &c).
Just as a data point, I have been using the "pedestrian" version of
this filter for several months (since 1997/08/06 07:15:59 sez RCS, but
that was a tweak of an earlier version) and it only caught one piece
of legit mail (and that was from a guy who was trying to write his own
MUA :-) ... but then that's mostly mail from a limited set of sources
(mailing lists, mostly Sendmail sites, mostly people using Pine, elm,
mutt, Pegasus, Eudora, etc).
/* era */
--
Paparazzi of the Net: No matter what you do to protect your privacy,
they'll hunt you down and spam you. <http://www.iki.fi/~era/spam/>