New Gmail Android App and Dovecot

[Miha Vrhovnik]

On 2016-11-16 20:39, David Flanigan wrote:
> Dovecot Users,
> 
> I have a sudden new problem that has cropped up just recently and I am
> stumped. My implementation has been working for over a year with no
> issues.
> 
> Version Data:
> Dovecot: v2.2.10 (using self signed certificates)
> openSSL: v1.01e
> Gmail Android App: v6.10.23 November 3, 2016
> 
> The issue:
> I use the iphone Gmail App to access my e-mail from phone and tablet. 
> It
> is simple and supports multiple accounts very nicely. This has worked
> for better than 18 months without issue.
> 
> This week I upgraded my Android app to the latest version of Gmail and 
> I
> stopped getting incoming e-mail. I can still pick up via outlook and
> other tools I use, but just not the android version of Gmail. When I
> attempt to pick up mail i see the below error in my log file.
> 
> _Nov 16 14:18:56 ns1 dovecot: imap-login: Disconnected (no auth 
> attempts
> in 0 secs): user=<>, rip=10.10.10.198, lip=10.1.1.10, TLS: SSL_read()
> failed: error:1408F10B:SSL routines:SSL3_GET_RECORD:wrong version
> number, session=<73vF8W9BdgCmrL7G>_
> 
> Disconnect and no new e-mail. There is no error in the Gmail app that I
> can find. The Gmail app works fine with my other accounts (Gmail, work,
> etc) so I am wondering if it is a configuration issue on my side or
> Gmail App stopped supporting something I was using.
> 
>  My SSl config is RPM standard other than SSL=yes and my self signed
> certificates.
> 
> Any thoughts would be appreciated.

This looks like the server or the client is trying to negotiate the 
SSL3. Look at the dovecot config and set the SSL protocols to TLS1.2, 
tls1.1 and tls1 in this order.

Regards,
Miha