OC_User_IMAP Dovecot (no auth attempts in 0 secs)

[benbrummer]

After upgrading to 0.6.0 and modifying the config.php external users are not able to login. In the maillog only one line gets logged, after entering the credentials.
Mar 25 02:31:22 mail dovecot: imap-login: Disconnected (no auth attempts in 0 secs): user=<>, rip=46.163.73.154, lip=46.163.73.154, TLS, session=<JmSBKeGE2Owuo0ma>

Nextcloud logs
{"reqId":"XJgwzy6jSZoAADDtgekAAAAF","level":2,"time":"2019-03-25T01:37:26+00:00","remoteAddr":"92.117.153.184","user":"--","app":"core","method":"POST","url":"/login?user=user%40domain.com","message":"Login failed: 'user@domain.com' (Remote IP: '92.117.153.184')","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:66.0) Gecko/20100101 Firefox/66.0","version":"15.0.5.3","id":"5c9832441bd5d"}

Nextcloud 15.0.5 with php 7.2 on Ubuntu 16.04 with mailserver on one machine (vserver with plesk)

User_backend from config.php
'user_backends' =>
array (
0 =>
array (
'class' => 'OC_User_IMAP',
'arguments' =>
array (
'my-mail-server.com', 993, 'ssl', ''
),
),
),

[benbrummer]

When switching dovecot to courier
Mar 25 03:59:30 mail courier-imaps: couriertls: accept: error:14094418:SSL routines:ssl3_read_bytes:tlsv1 alert unknown ca
php 7.3 same error

[benbrummer]

#52 (comment) another user with same problem

[violoncelloCH]

#52 (comment) another user with same problem

yes, thank you for reporting!
I would like to keep this issue open to discuss it here
cc @PaulFreund

[tweibert]

Same issue here (Login failed; "no auth attemps" in Dovecot log). After an hour of trying different options, and comparing to my Roundcube configuration, I was able to solve it by manually specifying CRAM-MD5 as authentication type by manually editing imap.php from

$params = ["port"=>$this->port, "timeout"=>10];

to:

$params = ["port"=>$this->port, "timeout"=>10, "auth_type" => "CRAM-MD5"];

This is probably because I'm using CRAM-MD5 passwords (the default?) in my Dovecot passdb. Likewise, I have to use

$config['imap_auth_type'] = 'CRAM-MD5';

in my Roundcube configuration.

Bottom line: The Roundcube IMAP class supports a lot of more parameters than just "port" and "timeout", and we need a way to specify them in the user_backends configuration please.

[benbrummer]

@tweibert thanks this fixed it on my side, too

[violoncelloCH]

thank you @tweibert for investigating into this!
I'll try to find the best way to allow to pass additional parameters.

[tweibert]

I propose you add a fifth, optional, parameter which is an associative array that is merged into $params.

[violoncelloCH]

yes, that should be doable...
would you like to do this @tweibert? I would be happy to merge a PR :) (this would greatly accelerate it, because my time as a student is limited and there are lots of other things to do for user_external)

[tweibert]

I wish I could do a PR, but I don't do PHP development normally, and I have absolutely no knowledge about the structure of the project. I don't feel fit for the job. Will probably break things instead of fixing them ;)

And when it comes to available time - I wish I had as much today as I had as a student (being a father of two, and a self-employed software dev - no PHP though).

[violoncelloCH]

I see...time is precious (however you could learn new things ;) )

if anyone wants to try (just state so here):
The relevant lines would be https://github.com/nextcloud/user_external/blob/master/lib/imap.php#L20-L40 (where we need to make sure, that additional parameter array from config.php will be passed into the class by the constructor) and then https://github.com/nextcloud/user_external/blob/master/lib/imap.php#L73 (where the parameters are passed to roundcube)...
If you have questions - just ask.