Hi everybody,
We've just had our email server used as a spam relay (It's and old MS
Exchange server, crap I know but it works most of the time) and some for
some political reason we can't upgrade it to a newer version that stops mail
relaying, so I've been asked to put some sort of proxying/filtering on the
OpenBSD firewall I'm building.
All it needs to do at the moment is some very lightweight checks on the
source and destination addresses, the best I've come up with is the
smtpd/smtpfwdd packages in the OpenBSD ports tree.
They seem a bit heavyweight for my needs and I was wondering if any simpler
programs that exist that just listen for connections, check that the HELO,
FROM and RCPT headers and if they are valid pass the data through to the
main server.
Does anything like this exist?
Any good reading material, RTFM's/A HREF's?
I am thinking I will probably have to write this my self as its quite a
specialist program, but it should be fun little hack.
Anybody else interested/pointers?
Thanks, Sam Mason.
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