[nos-bbs] How to avoid SMTP spam mail in mqueue
Bob Tenty
bobtenty at gmail.com
Wed Mar 19 19:24:32 EDT 2014
Jose,
Have you defined this in your config.h before your compiled jnos?
#define SMTP_DENY_RELAY /* Refuse to relay msgs from hosts not in our
subnets */
After that you can enable relay for a subnet if you need it, like this
for example...
smtp relay add 44.123.99.1 0xffffff00
There is also a file called "refile" what is located in the jnos spool
directory what you can
use to filter email based on the "From:" addresses.
I will give you a couple of examples:
*@financier.com|*@* refuse
warbelventas at warbel.com.ar|*@* refuse
h*lampe at chello.nl|*@* refuse
*@astroexpo.com@*|* hold
printz9 at 1st.net|ve3tok@* refuse
See also the docs.
But again as already said by others, let Linux do the filtering.
This is of course a lot of work to setup and maintain.
Be also aware that spam filtering can cause a (very) high
CPU load on your computer, etc.
Bob VE3TOK
On 14-03-19 03:27 PM, Jose Ng Lee wrote:
> Thanks for the recommendations Michael.
>
> I have shorewall firewall block port 25 for two days and Jnos was good
> and no crash. Today, I tried open port 25 and monitored TUN0 with
> tcpdump. The smtp mail spam just keep flowing and my Jnos is
> accepting those spam mail for relay and crashing.
>
> As I understood, by default Jnos Deny Relay. I tried the commands
> "smtp deny relay" and "stmp relay deny" but not accepted.
>
> Still trying to find out why Jnos is accepting those e-mail instead of
> denying relay. Before, I don't have in Rewrite a specific define and
> all the spam e-mails accumulated in mqueue. Now, in Rewrite
> everything that is not defined is put in check. So, the check.txt
> file is growing larger (later delete) but at least is not smtp for
> delivered out.
>
> José / HP2AT
>
>
> ----- Original Message -----
> *From:* Michael E Fox - N6MEF <mailto:n6mef at mefox.org>
> *To:* Jose Ng Lee <mailto:hp2cwb at cwpanama.net> ; 'TAPR xNOS
> Mailing List' <mailto:nos-bbs at tapr.org>
> *Sent:* Monday, March 17, 2014 2:51 PM
> *Subject:* Re: [nos-bbs] How to avoid SMTP spam mail in mqueue
>
> For the greatest protection, run all email through your separate
> mail server. This includes:
> -- inbound connections from Internet hosts to your public I address,
> -- inbound connections from Internet hosts to your 44.x address
> via tunnel from the AMPRnet gateway, and
> -- inbound connections from other 44.x machines to your 44.x
> address via tunnels
>
> M
>
>
>
> Sent from my Verizon Wireless 4G LTE smartphone
>
>
> -------- Original message --------
> From: Jose Ng Lee
> Date:03/17/2014 8:39 AM (GMT-08:00)
> To: Michael E Fox - N6MEF ,'TAPR xNOS Mailing List'
> Subject: Re: [nos-bbs] How to avoid SMTP spam mail in mqueue
>
> Thanks Michael for the tips on how to protect my Jnos.
>
> I could block SMTP (port 25) on the Firewall for inbound mails to
> TUN0, but does that block also the good mail 44 route coming fron
> encap?
>
> I trying to figure out why my Jnos accepted all those incoming
> spam mail. It should have issue an SMTP DENY and not accepted
> those emails. Maybe, there is a script somewhere on my CentOS
> machine allowing the entrace. So will keep looking.
>
> José / HP2AT
>
>
> ----- Original Message -----
> *From:* Michael E Fox - N6MEF <mailto:n6mef at mefox.org>
> *To:* 'Jose Ng Lee' <mailto:hp2cwb at cwpanama.net> ; 'TAPR xNOS
> Mailing List' <mailto:nos-bbs at tapr.org>
> *Sent:* Monday, March 17, 2014 8:28 AM
> *Subject:* RE: [nos-bbs] How to avoid SMTP spam mail in mqueue
>
> Block direct inbound SMTP connections to JNOS.
>
> Set up an MX in Linux using all the modern spam avoidance
> mechanisms dynamic black lists, UBE detection, signature-based
> detection, etc.) and send all inbound email to JNOS through
> that mail server using an MX record in DNS.
>
> Michael
>
> N6MEF
>
> *From:*nos-bbs-bounces at tapr.org
> <mailto:nos-bbs-bounces at tapr.org>
> [mailto:nos-bbs-bounces at tapr.org] *On Behalf Of *Jose Ng Lee
> *Sent:* Sunday, March 16, 2014 10:55 PM
> *To:* TAPR xNOS Mailing List
> *Subject:* [nos-bbs] How to avoid SMTP spam mail in mqueue
>
> I noticed today my Raspberry Pi Jnos was respawing in every
> few minutes. So, I checked and found out there was some spam
> e-mails in mqueue not been able to deliver and causing the
> system to crash and respawn. Deleted those e-mails and
> checking the logs and put in blacklist the offender IPs.
>
> I play with 3 Jnos systems:
>
> Main systems PC with Linux Ubuntu 12.04 LTS: onx.hp2at.ampr.org
>
> No spam mail in mqueue.
>
> Raspberry Pi with Raspbian: hp2ng.ampr.org
>
> Few spam mail in mqueue.
>
> PC with Centos 5.9: hp2sa.ampr.org
>
> THOUSANDS of spam mail in mqueue. Don't know how this got
> through or why it was received in JNOS. The autoexec.nos is
> the same as my other system.
>
> This is on the message heading on one mail:
>
> Received: from pc-200402271018 by hp2sa.ampr.org (ONXSA BBS)
> with SMTP
> id AA24803 ; Thu, 13 Mar 2014 03:17:52 EST
> From: =?BIG5?B?pWqo5a21vNY=?= <springboard at yahoo.com
> <mailto:springboard at yahoo.com>>
> To: "awze" <awze at awze.com <mailto:awze at awze.com>>
> Subject:
> =?BIG5?B?RGlzbmV5qOC1o7nPrtGhQqlfpf2lzaeupHCpaiC1paqpxXao7LTBuc+u0aFCpfq6?=
> =?BIG5?B?0KRqpViyTaFJ?=
> Date: Wed, 28 Apr 2004 22:58:06 +0800
> MIME-Version: 1.0
> Content-Type: text/html;
> charset="Big5"
> Content-Transfer-Encoding: quoted-printable
> X-Priority: 3
> X-MSMail-Priority: Normal
> X-Mailer: Microsoft Outlook Express 6.00.2800.1106
> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106
> Message-Id: <24804 at hp2sa.ampr.org <mailto:24804 at hp2sa.ampr.org>>
>
> Took this JNOS offline until the problem solve.
>
> Please can anyone know a way to deny receiving spam mail in jnos.
>
> Thanks,
>
> José / HP2AT
>
>
>
> _______________________________________________
> nos-bbs mailing list
> nos-bbs at tapr.org
> http://www.tapr.org/mailman/listinfo/nos-bbs
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/nos-bbs_lists.tapr.org/attachments/20140319/06001f42/attachment.html>
More information about the nos-bbs
mailing list