tlsv1 alert unknown ca: SSL alert number 48

[Maurizio Dall'Acqua]

I think that you are right when you say that the problem may be the
certificate recognition.

As for Roundcube, I've inserted the uncommented php code that you provided 
in /usr/share/roundcube/main.inc.php.dist, which is the Raspbian file for 
/config/defaults.inc.php. Unfortunately Roundcube doesn't login and replies
 with the message "connection to storage server failed". And the log file 
of dovecot gives the reason: unknown certificate.

In order to solve this problem do you think that I should look into the
configuration file of Squirrelmail/Roundcube or in the config file of
Dovecot?


On Wed, Jun 15, 2016 at 05:48:32PM -0400, Gedalya wrote:
> On 06/15/2016 04:26 PM, Maurizio Dall'Acqua wrote:
> > Hi,
> >
> > I have set up a mail server with postfix+dovecot 2.2.13 on my raspberry pi
> > running Raspbian Jassie OS.
> >
> > Now I would like to add an on-line e-mail client like Squirrelmail or
> > Roundcube. I was able to start up these two clients but when I try to login
> > I get this error message in the dovecot log:
> >
> > tlsv1 alert unknown ca: SSL alert number 48
> >
> > But I have inserted the self-signed certificate and key in
> > /etc/dovecot/conf.d/10-master.conf
> >
> > Moreover, I can send and receive e-mails from/to my server, and I can login
> > successfully to dovecot IMAP with Thunderbird.
> >
> > Can somebody give me a clue on how to solve this problem? Any help would me much
> > appreciated.
> >
> > Regards,
> > Maurizio
> 
> This could mean that the client has indicated it was unable to verify the server's certificate.
> 
> With regards to Roundcube, see this in config/defaults.inc.php:
> 
> //$config['imap_conn_options'] = array(
> //  'ssl'         => array(
> //     'verify_peer'  => true,
> //     'verify_depth' => 3,
> //     'cafile'       => '/etc/openssl/certs/ca.crt',
> //   ),
> // );
> 
>