From - Fri Sep 19 07:18:05 1997
Path: news.mitre.org!blanket.mitre.org!news.tufts.edu!cam-news-feed5.bbnplanet.com!cam-news-hub1.bbnplanet.com!news.bbnplanet.com!news.maxwell.syr.edu!Supernews60!supernews.com!news.nap.net!news2.nap.net!news.dls.net!not-for-mail
From: Sam Rozenfeld <rozenfeld@dls.net>
Newsgroups: comp.os.vms
Subject: Quick spam scanner for MX 4.2
Date: Thu, 18 Sep 1997 20:20:32 -0500
Organization: DLS Internet Services
Lines: 39
Message-ID: <3421D360.40D5@dls.net>
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$!
$! This is a quick spam Filter for MX 4.2. After extensive spam attacks we have
$! noticed that few bulk emailers are using the same method to generate
$! fake random email addresses. Addresses look something like 
$! <12432134@aol.com>. It is safe to assume that if we convert the part of
$! email address before "@" into an integer and get value greater than 10 - 
$! username is likely a spammer.
$!
$! We also have a filter to do it only to outgoing mail. But incoming mail
$! could be taken care of too. We have this running every 5 minutes now but
$! feel free to run it however often you want.
$!
$! 09/18/1997 Sam Rozenfeld
$!
$ mcp :== $mx_exe:mcp
$ on control_y then goto endit
$ mcp show queue/output=mxqueue.lis
$ sear/output=temp.lis mxqueue.lis "<" 
$ open/read mxqueue temp.lis 
$ loop:
$ read/end=endit mxqueue record
$!
$! Only do SMTP (outgoing)
$!
$ if f$locate("SMTP",record) .eqs. f$length(record) then goto loop
$ address = f$extract(f$locate("<",record),f$locate(">",record),record)
$ full_ad = address - "<" - ">"
$ address = f$extract(full_ad,f$locate("@",full_ad),full_ad)
$ if f$integer(address) .gt. 10 
$       then 
$       mail_id = f$edit(f$extract(0,7,record),"trim")
$       mcp queue cancel 'mail_id'
$       write sys$output "''full_ad' is a spammer - entry ''mail_id' cancelled"
$ endif
$ goto loop
$ endit:
$ close mxqueue
$ purge mxqueue.lis,temp.lis
$ exit