Re: IMAP & SMTP services

[Jason Lunz <lunz@falooley.org>]

andrew@cpplating.com.au said:
> 1.  Which packages do I need to install to get a ssl encrypted IMAP server
> running?

install courier-imap-ssl.

> 2.  How can I set up Exim so that my boss can send email through our company
> web server from anywhere in the world without opening myself up to relaying
> for everyone?  He uses GRIC global roaming Internet - and every ISP he dials
> into needs a different SMTP server to be entered into his mail client
> (Outlook 98).
>
> I've thought about setting up a password to access EXIM, but I can't seem to
> find a way to do it in the documentation.  I also don't know if a password
> would override the lack of relay_domains.

In the first section of exim.conf, add:

	host_auth_accept_relay = *
	auth_always_advertise = false

in the final section, authentication configuration, put:

	plain:
	  driver = plaintext
	  public_name = PLAIN
	  server_condition = ${if and {{eq{$2}{USERNAME}}{eq{$3}{PASSWD}}}{yes}{no}}
	  server_set_id = $2

	login:
	  driver = plaintext
	  public_name = LOGIN
	  server_prompts = "Username:: : Password::"
	  server_condition = ${if and {{eq{$1}{USERNAME}}{eq{$2}{PASSWORD}}}{yes}{no}}
	  server_set_id = $1

now, any machine on the internet can send mail through your SMTP server,
but only if it authenticates using USERNAME/PASSWORD. You can make these
whatever you want. The example above gives a global user/pass that
_anyone_ can use. I find that to be sufficient for a small group. You
can do more elaborate things with exim's database lookup capabilities.

Also, you might run into the problem where some ISPs disallow outgoing
connections to port 25 in order to stop spammers. I'm pretty sure
earthlink does this. If your boss connects from one of these networks,
he won't be able to send mail. To handle that, I use NAT on the server
to redirect connections to an unused port (like 24) to 25, then
configure clients to connect to port 24.

Jason