dovecot - Jun 2020 - Password mismatch after upgrade to Ubuntu Focal

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?

dovecot -n
-------------------------
# 2.3.7.2 (3c910f64b): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.5.7.2 ()
# OS: Linux 5.4.0-33-generic x86_64 Ubuntu 20.04 LTS ceph
# Hostname: server.example.tld
auth_verbose = yes
disable_plaintext_auth = no
listen = *, [::]
log_timestamp = "%Y-%m-%d %H:%M:%S "
login_greeting = POP/IMAP Service ready.
mail_fsync = always
mail_location = maildir:/mail/%u
mail_privileged_group = mail
passdb {
  args = /etc/dovecot/dovecot-ldap.conf
  driver = ldap
}
plugin {
  acl = vfile:/etc/dovecot/acls/:cache_secs=30
  autosubscribe = Trash
  autosubscribe2 = Sent
  autosubscribe3 = Drafts
}
protocols = imap pop3
service auth {
  user = root
}
service imap-create-folder {
  executable = script-login /usr/local/sbin/dovecot-create-dirs.sh
}
service imap-login {
  process_min_avail = 15
  service_count = 0
}
service imap {
  executable = imap imap-create-folder
}
service pop3-login {
  process_min_avail = 15
  service_count = 0
}
service pop3 {
  drop_priv_before_exec = yes
}
ssl = no
userdb {
  driver = prefetch
}
protocol imap {
  mail_max_userip_connections = 25
  mail_plugins = acl
}
protocol pop3 {
  pop3_uidl_format = %f
}
------------------------------

/etc/dovecot/dovecot-ldap.conf
------------------------------
hosts = ldap.server.example.tld

dn = <XXXXX>
dnpass = <XXXXX>
auth_bind = no
ldap_version = 3
base = <XXXXX>

pass_attrs = <XXXXX>
pass_filter = <XXXXX>
-----------------

Thanks!

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?
> 
> 
Hi,

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

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

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

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

>>>>> "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