On 20.1.2012, at 0.30, Harm Weites wrote:
we want to use dovecot LMTP for efficient mail delivery from our MX servers (running postfix 2.8) to our storage servers (dovecot 2.0.17). However, the one problem we see is the lack of access control when using LMTP. It apears that every client in our network who has access to the storage machines can drop a message in a Maildir of any user on that storage server.
Is it a real problem? Can't they just as easily drop messages to other users' maildirs simply by sending the mail via SMTP?
To prevent this behaviour it would be nice to use libwrap, just as it can be used for POP3/IMAP protocols. This, however, seems to be impossible using the configuration as mentioned on the dovecot wiki:
login_access_sockets = tcpwrap
This seems to imply it only works for a login, and LMTP does not use that. The above works perfectly when trying to block access to IMAP or POP3 in /etc/hosts.deny, though a setting for LMTP is simply ignored.
Right. I'm not sure if I'd even want to add such feature to LMTP. It doesn't really feel like it belongs there.
Is there a configuration setting needed for this to work for LMTP, or is it simply not possible (yet) and does libwrap support for LMTP requires a patch?
Not possible in Dovecot currently. You could use firewall rules.