[Samba] a way to migrate pasword from Samba 4.0 AD DC to new AD DC?

[Franta Hanzlik]

Dne 2024.08.14 10:16, Rowland Penny via samba wrote:
> On Wed, 14 Aug 2024 05:56:22 +0200
> Franta Hanzlík via samba <samba at lists.samba.org> wrote:
> 
>> Please, is there any way to migrate passwords from old Samba 4.0 Ad DC
>> to new (Samba 4.20) one?
> 
> Yes, add another DC, but you will probably have to do it in stages,
> Samba 4.0.x went EOL 9 years ago. I think you would have to upgrade to
> 4.5.x then 4.20.x

The new AD domain name will be different than it is on the old 4.0 DC,
so I'd rather start with a clean install.
I'm not an AD guru and I'm afraid of problems ;)

>> On ldbsearch export on old AD only related item I see is 'unicodePwd'
>> attribute, and it is maybe possible write to new system using
>> ldbmodify
>>  - but it is right and simplest solution?
> 
> No it isn't right and it isn't simple. The password you get back if you
> ask for the contents of the unicodePwd isn't the password, it is the
> 64bit encoding of the password, which doesn't seem to be reversible.
> You also cannot just write a password to the unicodePwd attribute, it
> has to be encoded in a precise way and written over SSL.

I meant using ldbmodify to write directly the base64 string obtained from
the old DC, directly on the AD DC machine. This would work without TLS and
even without Samba running, and it should be possible to write just about
anything, any value, to the attribute. Or am I mistaken?

>> And one more question - why don't I get any result from the command
>> (on 4.20 AD DC, provisioned with --plaintext-secrets):
>> 
>> # samba-tool user getpassword testusr
>> --attributes=unicodePwd,virtualClearTextUTF16,virtualClearTextUTF8
>> on: CN=testusr,OU=users,DC=ad,DC=my,DC=home unicodePwd::
>> CkODmLSx+ZaJO/qHDQibNw== Got password OK
>> 
>> Why are the virtualClearTextUTF16 and virtualClearTextUTF8 values ​​
>> missing and how do I make them exist?
>> Does using the 'samba-tool user syncpasswords' command have anything
>> to do with this?
> 
> Have you actually set them ?

Do I have to set them myself?
By what?
There is no option here for Samba to do this itself?
Isn't it initiated by the 'samba-tool user syncpasswords' command?

> Why do you need plaintext passwords ?

Some authentication mechanisms require a cleartext password on the server 
side.

-- 
Thanks, Franta Hanzlik