[Wylug-discuss] Re: Please confirm... follow up

[James Holden (WYLUG)]

All,

Just one final point, because it hasn't been made... the installation of
TMDA I set up does auto-whitelisting, so you would only ever have to
confirm one message, and then it never bothers you again. Honestly, how
much hassle is that?

Also, I'm playing with the sender address verification on Postfix,
having managed to patch a recent snapshot to get TLS support. It looks
promising, but still not perfect, because many MX's will accept mail for
any address. eg:

I got some spam claiming to be from:

zeRutI at its-server.novell.leeds.ac.uk (coincidentally)

# nslookup
Default Server:  my.dns.server
Address:  192.168.1.254

 > set type=MX
 > its-server.novell.leeds.ac.uk
Server:  my.dns.server
Address:  192.168.1.254

Non-authoritative answer:
its-server.novell.leeds.ac.uk   preference = 8, mail exchanger =
mps8.leeds.ac.uk
its-server.novell.leeds.ac.uk   preference = 8, mail exchanger =
mps9.leeds.ac.uk
 > exit
# telnet mps8.leeds.ac.uk 25
Trying 129.11.6.10...
Connected to mps8.leeds.ac.uk.
Escape character is '^]'.
220 mps8.leeds.ac.uk ESMTP Sendmail 8.12.10/8.12.10; Thu, 18 Mar 2004
13:57:29 GMT
HELO my.real.hostname.and.it.does.resolve
250 mps8.leeds.ac.uk Hello me.leed.broadband.ntl.com [80.x.y.z], pleased
to meet you
MAIL FROM: <>
250 2.1.0 <>... Sender ok
RCPT TO: zeRutI at its-server.novell.leeds.ac.uk
250 2.1.5 zeRutI at its-server.novell.leeds.ac.uk... Recipient ok
DATA
354 Enter mail, end with "." on a line by itself