From owner-freebsd-questions@FreeBSD.ORG Sun Dec 16 19:53:35 2007 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4718A16A419 for ; Sun, 16 Dec 2007 19:53:35 +0000 (UTC) (envelope-from jack@jarasoft.net) Received: from raats.xs4all.nl (raats.xs4all.nl [82.95.230.43]) by mx1.freebsd.org (Postfix) with ESMTP id B3B1213C458 for ; Sun, 16 Dec 2007 19:53:34 +0000 (UTC) (envelope-from jack@jarasoft.net) Received: from raats.xs4all.nl (localhost.jarasoft.net [127.0.0.1]) by raats.xs4all.nl (Postfix) with ESMTP id 0519116A87A; Sun, 16 Dec 2007 20:53:33 +0100 (CET) Received: from jara3 (unknown [192.168.1.64]) by raats.xs4all.nl (Postfix) with ESMTP id 7C0EA16A464; Sun, 16 Dec 2007 20:53:32 +0100 (CET) Message-ID: <002a01c8401d$56186e10$0202fea9@jarasoft.net> From: "Jack Raats" To: "Sten Daniel Soersdal" , "freebsd-questions" References: <476086E2.5030402@gmail.com> Date: Sun, 16 Dec 2007 20:53:32 +0100 Organization: JaRaSoft, Steenbergen, Nederland MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="UTF-8"; reply-type=response Content-Transfer-Encoding: 7bit X-Priority: 1 X-MSMail-Priority: High X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 X-Signed-With-GnuPG: GPGrelay Version 0.959 (Win32) X-Virus-Scanned: ClamAV using ClamSMTP Cc: Subject: Re: (postfix) SPAM filter? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Jack Raats List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 16 Dec 2007 19:53:35 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Sten and the rest, > We have a need for a relatively painless anti-spam solution that would > reduce the amount of incoming spam (via postfix mail router). The problem > is that i have little knowledge on what this actually means. Googling > reveals a whole "universe" of interesting ways but what should i pursue? > The things that are important to me is: > > * Once it is setup then it would require no additional maintenance. > * Potential spam messages are marked with a special header that can be > filtered on user discretion on their local mail client software. > > Neither performance, scalability, license nor cost is of much importance > to me at this point. I have a different approach. I refuse all connections from ip's which reverse DNS points to costumers of providers. This gives a huge reduction of botnets. Below my helo_checks and client_checks. Ofcourse use it for your own risk! Besides this method I also use rbls's, greylisting, clamsmtpd, clamav, procmail and spamassasin ####################################################################### # helo_checks.pcre ####################################################################### /^[0-9.]+$/ REJECT Please use your ISP's outgoing mail server - HA /^\|/ REJECT Please use your ISP's outgoing mail server - HB /^[\d\.]+$/ REJECT Please use your ISP's outgoing mail server - HC # H1 adsl,dial,dhcp,cable,retail,dynamic in helo /(adsl|dial|dhcp|cable|retail|dynamic)/i REJECT Please use your ISP's outgoing mail server - H1 # H2 customer,static,kabel in helo /(customer|static|kabel)/i REJECT Please use your ISP's outgoing mail server - H2 # H3 12345 # /\d{5}/ REJECT Please use your ISP's outgoing mail server - H3 # H4 123-123-123 /\d{1,3}-\d{1,3}-\d{1,3}/ REJECT Please use your ISP's outgoing mail server - H4 # H5 123.123.123 # /\d{1,3}\.\d{1,3}\.\d{1,3}/ REJECT Please use your ISP's outgoing mail server - H5 ####################################################################### # client_checks.pcre ####################################################################### # C1 adsl,dial,dhcp,cable,retail,dynamic in hostname /(adsl|dial|dhcp|cable|retail|dynamic)/i 554 Please use your ISP's outgoing mail server - C1 # C2 customer,static,kabel in hostname /(customer|static|kabel)/i 554 Please use your ISP's outgoing mail server - C2 # C3 123456 /\d{6}/ 554 Please use your ISP's outgoing mail server - C3 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (MingW32) - GPGrelay v0.959 iD8DBQFHZYI8Ph5RwW/NzC4RAj1uAJ9saKRz9Q+daCcU7D/plXGRAdXflACfQ3KR DpXkjMrMMITbqdSulZW8aBM= =D4lA -----END PGP SIGNATURE-----