Thomas Hummel wrote:
On Thu, Jul 31, 2008 at 03:26:06PM +0200, Thomas Hummel wrote:
I don't quite understand the proxy_maybe option :
The proxy_maybe allows you to have a user log into a server that is both doing proxy logins for another host as well as local logins. So User A connects into server 1, they live on server 2 so server 1 proxies the connection onto server 2. User B connects into server 1 and they live on server 1, so proxy_maybe allows the connect to be made direct even though their proxy setting says they go to a specific host (which happens to be server 1)
Also, 2 things which aren't quite clear to me in the Wiki :
a) Password forwarding
Make sure that the authentication succeeds with any given password. You can do this by using empty passwords. v1.1+ requires also that you return nopassword field.
-> Does that mean that the proxy has to accept only empty passwords and that that's the actual imap server that will deal with the actual password ?
The destination host must be set to allow plain text passwords.
b) The connections created to the destination server can't be TLS/SSL encrypted.
Does it still work if the client is using SSL/TLS to connect to the proxy ?
Yes the initial connection can be done using SSL/TLS. What happens is the proxy will do the auth for the user using their password and if it succeeds and they have a proxy attribute setup then the connect is made to the destination host using a plaintext connection. What you can do is setup a dovecot proxy host(s) that has no users assigned to that server and allows only SSL/TLS connections, then on the backend a bunch of servers that users get assigned to but they cannot have: disable_plaintext_auth = yes in the configuration.