I've been trying to get Exim to demand authentication before allowing
relaying to other
hosts (hosts_auth_accept_relay = *). This is the only relay related
option that i've set
in the configuration file. I am using Exim 3.16 #2 with support for
mysql and the plaintext
authenticator built in.
Problem is that none of the relay related settings seem to have any
effect, my mail server
will still allow anyone to relay even if I set none of the relay related
options.
(The manual says that Exim should not do this by default)
I've tried my configuration with "exim -bh <ip-address>" and that seems
to work, it correctly
says that you have to authenticate before you can relay to a non-local
domain (error 550)
However if I telnet to port 25 on my mail server it does allow relaying
regardless of the recipient or sender.
The only difference between the test 'exim -bh' session and the real
telnetted smtp session that I can find is that the in the test session
the response to the EHLO command is :
And the response that I get when telnetting to port 25 is :
EHLO test
250-local-hostname Hello mail at test
250...
I don't understand why Exim says I am user 'mail' ? (I am not even sure
that this
is related to the problem I am having with relaying, just a long shot)
Anyway, even when using a real MUA (instead of telnetting) it simply
will allow relaying without authentication.
