RE: email gateway (transparent) - full transparent

["Shawn Jackson" <sjackson () horizonusa com>]

        If you're using Linux routers at your remote sites you can
'intercept' the STMP request and mangle the header to point to your MX
servers. Of course that would require use of IPTABLES/IPCHAINS in
addition to your routing software, I.e. SQUID.

Shawn Jackson
Systems Administrator
Horizon USA
1190 Trademark Dr #107
Reno NV 89521
www.horizonusa.com
 
Email: sjackson () horizonusa com
Phone: (775) 858-2338
       (800) 325-1199 x338

-----Original Message-----
From: arek () chelmnet pl [mailto:arek () chelmnet pl] 
Sent: Thursday, November 13, 2003 11:33 AM
To: security-basics () securityfocus com
Subject: RE: email gateway (transparent) - full transparent


I'm using posftix+amavis+ polish (mks-vir) for virus scanning

pop-before smtp + ordb + few others db + local regexp database for stop
relaying and anti spam.

The result in relaying is 100% accurate, but spam is comming from time
to
time ( eg. V1@GRA).

But where my problem is:
My problem is with my local users (about 3k LAN users in about 500
buildings), they send spam (viruses, worms etc) not using my MTA.
I'm looking for transparent method (like redirect for transparent-proxy
w3cache, squid) to force traffic on port 25 to go via my MTA.

Do you have any ideas or experiences with that ?

I thought about writing own code for that, but im far far away from that
(begging with C proggramming and kernel hacking), instead i'm good in
mixing
every working capabilities wich are accessible and done before by
somebody
else ;)


BTW.
Well, if somebody is wondering how such LAN can work with linux routers
+
sql_db + local_scripting + php + bash = CRM and NETWORK_ADMINISTRATION,
BILLING_SOFTWARE, AUTOMATIC_EMAIL_OFFICE visit my own software (sorry -
but
is not in english and has 1mega pictures) http://nsm.pl/~arek/superedit
.
I'm interested in sharing my soft for development purposes or any other.


Arkadiusz Binder


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---------------------------------------------------------------------------
Forum Systems PRESIDIO: PGP / XML GATEWAY APPLIANCE
The Presidio integrates PGP data encryption and XML Web Services security to
simplify the management and deployment of PGP and reduce overall PGP costs
by up to 80%.
FREE WHITEPAPER & 30 Day Trial -
http://www.securityfocus.com/sponsor/ForumSystems_security-basics_031027
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