Re: Blocking spam

Page principale
Supprimer ce message
Répondre à ce message
Auteur: Chris Thompson
Date:  
À: David.Osborne
CC: exim-users
Sujet: Re: Blocking spam
David Osborne asks
>
> Am I right in thinking that the address syntax doesn't allow me to include
> regexps such as
> [0-9]+@somedomain.com
> or
> [0-9]+.com


Yes: lookups in address lists look up localpart@domain, then just domain, then
stripped versions of the domain if the lookup is partial.

> As spammers seem to increasingly use From addresses of the form [0-9]+@xyz.com,
> what's the best way to block these? A systemwide filter file? An example would
> be great.


In 1.625 [*please* take note of Philip's warning about using testing releases
at your own risk] onwards there is a nice new sort of lookup in address lists,
specified by "@@lsearch;/file/name", "@@partial0-dbm;/another/name", etc. This
looks up the domain (and stripped versions if the search is partial) and
interprets the result as a colon-seperated list of tests to be applied
to the localpart (exact values, *suffix, ^regexp, even more elaborate things).

We are using this locally to good effect. And yes, patterns like ^[0-9]+$ crop
up quite a bit...

Chris Thompson               Cambridge University Computing Service,
Email: cet1@???    New Museums Site, Cambridge CB2 3QG,
Phone: +44 1223 334715       United Kingdom.