sendmail SMTP Authentication small problem

[Kevin J. Cummings]

ipsystem wrote:
> I have made SMTP Authentication with this how-to page. http://www.sendmail.org/~ca/email/auth.html
> 
> It work fine.
> Any one spamer can't send mail via my smtp server.

Its never a good idea to run an open SMTP relay.  Spammers live for 
those.  I thought by default, the Fedora Core sendmail server did not 
allow relaying (I know you have to tweak it to accept mail from other 
than localhost by default).  I remember when I commented out the:

> dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl

line, I had to allow all the machines on my local network to access 
sendmail through the /etc/mail/access file in order to send email.

> But he can send mail via my smtp to my_user at my_domain.com without authentication!
> How to forbid and it too?

If you want to accept email from the internet, in general, to your 
domain, you're kinda stuck.  You can block specific users/domains/ips in 
the /etc/mail/access file, but if spammers change IP addresses and 
domain names all the time, so you're basically SOL....

> I searched in the documentation to sendmail but have found nothing.

I basically gave up and started concentrating on removing the spam 
before it gets to my Inbox with RBL, SPF, SpamAssassin, and junk email 
filters in my MUA.  Its still not perfect, but it helps a lot!

-- 
Kevin J. Cummings
kjchome at rcn.com
cummings at kjchome.homeip.net
cummings at kjc386.framingham.ma.us