Password mismatch after upgrade to Ubuntu Focal

[John Stoffel]

>>>>> "Jeffrey" == Jeffrey van Doesburg <jeffrey at bit.nl> writes:

Jeffrey> On Mon, 2020-06-15 at 12:24 +0200, Jeffrey van Doesburg wrote:
>> Hi!
>> 
>> Today I upgraded one of our Dovecot servers from Ubuntu 18.04 to
>> Ubuntu
>> 20.04. After the upgrade I have login issues because the password
>> didn't match.
>> 
>> I also installed Dovecot on a clean Ubuntu 20.04 server with the same
>> configuration files. And here I also got the password match issue.
>> 
>> We're using LDAP for managing the login credentials and I'm 100% sure
>> the password is correct. With the debug options on, you will see
>> something like this:
>> 
>> CRYPT(<PLAIN_TEXT_PASSWORD>) != '$6$<SECRET_PASSWORD_HASH>'
>> 
>> Does somebody know if there are know issues with Dovecot 2.3.7.2-
>> 1ubuntu3.1 on Ubuntu 20.04 and with the LDAP driver?

Jeffrey> Little update about the "password mismatch" error. I tried
Jeffrey> different versions of Dovecot on Ubuntu 18.04 and 20.04. And
Jeffrey> it looks like it's something in Ubuntu that cause the
Jeffrey> error. Because Dovecot 2.3.10.1 works fine on Bionic and on
Jeffrey> Focal it gives a "password mismatch" message.

Jeffrey> Focal:
Jeffrey> - 2.3.7.2-1ubuntu3.1 from Ubuntu main repo (Password Mismatch)
Jeffrey> - 2.3.10.1 compiled from source (Password Mismatch)

Jeffrey> Bionic:
Jeffrey> - 2.2.33.2-1ubuntu4.5 from Ubuntu main repo (IMAP works)
Jeffrey> - 2.3.10.1 compiled from source (IMAP works)

Jeffrey> If someone has a clue, I would like to hear it! :)

What if you compile on Bionic and run it on Focal, does it still work
or fail?  Can you give the 'ldd' output of each as well, so we can see
which versions of the various libraries you have installed?

And what about if you don't use LDAP, but just use an sqlite3 or even
just a plain flat file for authentication, to try and figure out if
it's dovecot's problem, or maybe something in LDAP that changed as
well?

My dovecot setup just uses sqlite3, so I can't really help much on the
LDAP side.

Good luck!
John