after upgrade to PVE 6.0 don't work AD auth with SSL

[kaa]

Hi All!

I had a test cluster PVE 5.4 with authentication thru Active Directory (Win 2008 R2) with SSL enabled, worked well.

After upgrade to PVE 6.0 any user got message "Login failed. Please try again" while trying to log on.

In log I see:
Aug 17 07:59:17 pve-test-00114983 pvedaemon[3008247]: authentication failure; rhost=10.1.1.46 user=kaa@ad.test.org msg=SSL connect attempt failed error:1425F102:SSL routines:ssl_choose_client_version:unsupported protocol

If I disable SSL in Authentication properties page for AD record, users logged successfully.

Please, help with this issue - clear text password on network (without SSL) is big security hole.

 

[gradinaruvasile]

I observed the same thing, in the pvedaemon logs i see

authentication failure; rhost=host_ipaddr user=username@domain msg=Connection reset by peer

 

[gradinaruvasile]

So i got the solution for this.
Openssl from Debian Buster has an enforced encryption of TLS 1.2.
Older Windows Server versions have some older implementations, although they do seem to use 1.2 in the end.
The solution is either
1. to change

/etc/ssl/openssl.cnf

and change

MinProtocol = TLSv1.2

to:

MinProtocol = TLSv1.0

then

systemctl restart pvedaemon

2. Install a newer Windows server for DC (on our newer Windows 2016 DCs the login worked, but not on the older 2012 R2s).