imap connection to gmail closes connection

[Maxim Dounin]

Hello!

On Wed, Jan 15, 2014 at 10:37:29AM -0500, bidwell wrote:

> I am running nginx 1.1.19 on an Ubuntu 12.04.4 64but server.
> 
> I have nginx configured to enter on port 143 and go out to 127.0.0.1:143
> where it goes through stunnel to go to imap.gmail.com:993. If I talk
> directly to 127.0.0.1:143 (to stunnel) it works. If I talk to nginx, it
> authenticates, logs correct username, target IP and port, gets the
> Capability list and registers a successful login to the remote (gmail) imap
> server and then closes the connection immediately. The following is a
> transcript of the telnet session:
> 
> telnet nginx:143
> * OK IMAP4 ready
> a1 LOGIN user at example.com password
> * CAPABILITY IMAP4rev1 UNSELECT IDLE NAMESPACE QUOTA ID XLIST CHILDREN
> X-GM-EXT-1 UIDPLUS COMPRESS=DEFLATE ENABLE MOVE CONDSTORE ESEARCH
> a1 OK user at example.com first_name Last_name authenticated (Success)
> Connection closed by foreign host.
> 
> My nginx error.log shows the following:
> *5 upstream sent invalid response: "* CAPABILITY IMAP4rev1 UNSELECT IDLE
> NAMESPACE QUOTA ID XLIST CHILDREN X-GM-EXT-1 UIDPLUS COMPRESS=DEFLATE ENABLE
> MOVE CONDSTORE ESEARCH
> a1 OK test at example.com Test User authenticated (Success)" while reading
> response from upstream,...
> 
> It appears to not like google's CAPABILITY line. Is it too long? Any
> suggestions?
> 
> Other connections through nginx/stunnel to exchange work just fine.

The problem is that nginx doesn't expect multiple responses to the 
LOGIN command.

-- 
Maxim Dounin
http://nginx.org/