[Mimedefang] blocking | and bad syntax in "from" address

[Paul Heinlein]

On Fri, 18 Jun 2004, Joe Arnstein wrote:

> I've been noticing a lot of spam coming in with characters in the 
> "from" address that don't work or are likely to be forged.  These 
> cause a backup in our outbound queue (lots of NDRs) so I'd rather 
> they be rejected right off the bat.
>
> from=<_mohammad at ameritech.net>
> from=<Puri|puri at nt.com>
> from=<Rauly|rauly at ns4b.com>
> from=<.samuel at whereever.com>
> from=<80/joan.smith at spamcorp.com>
> from=<A/uykgYBAQAIAOgB9QAAAAAEAAApGQ at edailydiscounts.com>
>
> Do any of the rfc's say this is improper syntax or forbiden 
> characters? Should I block this?  Can I block it? And if so can 
> someone recommend a good way to do it?

Anthony Howe's milter-spamc rejects such things with "553 5.1.[37]" 
errors. I've never looked at his code, but it seems to work decently 
on my home mail server (which doesn't need mimedefang's flexibility).

--Paul Heinlein <heinlein at cse.ogi.edu>