Bug#1130068: should not recommend libnss-winbind/libpam-winbind

2026-03-08 Thread Steinar H. Gunderson
On Sun, Mar 08, 2026 at 12:38:59PM +0300, Michael Tokarev wrote:
> However, I'm not at all sure about nss-winbind.  I just don't
> know if AD-DC uses it or not.

I've run Samba 4 DCs basically since the alpha stage and never used
nss-winbind, so I don't think they're essential by any means, at least.

> I don't know if it's possible to address this in trixie (definitely not
> in the upcoming 13.4 release as it will happen next week already).  But
> I'll fix this for forky at least.

Yeah, sorry for not catching it before trixie release. :-)

/* Steinar */
-- 
Homepage: https://www.sesse.net/



Bug#1130068: should not recommend libnss-winbind/libpam-winbind

2026-03-08 Thread Michael Tokarev

Control: severity -1 important
Control: tag -1 + confirmed

On 08.03.2026 11:15, Steinar H. Gunderson wrote:

Package: samba-ad-dc
Version: 2:4.22.6+dfsg-0+deb13u1
Severity: normal

Hi,

If you do as the trixie release notes say, and “apt install samba-ad-dc”
on your DC upgrade, you will (more or less silently) get libnss-winbind
and libpam-winbind on your DC. This means that by default (i.e., unless
you add some extra restrictions somewhere), every user on your domain
can log into your DC.


Actually this is worse.  When splitting up samba-ad-dc out of samba,
besides the release notes, I also added Recommends: samba-ad-dc to
the samba package, - in a hope that for those who used samba with
DC functionality, no extra package installation will be required
(and it works).

However, as you correctly noted, samba-ad-dc recommends libpam-winbind
and libnss-winbind - which means that now, everyone who used to have
samba installed for any reason, pam+nss winbind modules are installed
*too*.

And this leads to somewhat unusual password prompts, strange error
messages when password is incorrect, and so on.  All these are cosmetics,
but the problem is actually much deeper, as you noted above.

I never thought about it all this way.  And yes, you're right,
pam-winbind isn't needed for ad-dc in any way.

However, I'm not at all sure about nss-winbind.  I just don't
know if AD-DC uses it or not.


This is an unusual configuration; pretty much every DC I've seen is
set up separated from normal users for security reasons. And given that
the main samba package does _not_ have such a Recommends (winbind itself
has a Suggests, which sounds like the right thing to me), I'm not sure
why samba-ad-dc specifically would have it? It doesn't seem to fit with
what Recommends generally means in Policy (“The Recommends field should
list packages that would be found together with this one in all but unusual
installations”; I would assume _installing_ them is the unusual setup).
Of course you can install them and then set up e.g. group ACLs in
sshd_config, but it's not obvious to me why this should be the default
setup.

I must admit I don't even understand why winbind is needed to run a DC,
but I'm sure there is some internal Samba reason, given that it is a
Depends. :-)


This is another very good question.  I don't know.

And this is more about documentation, or lack thereof.

It would be excellent to have some comments from the samba team on the
matter, - I'll ask there.

I don't know if it's possible to address this in trixie (definitely not
in the upcoming 13.4 release as it will happen next week already).  But
I'll fix this for forky at least.

Thanks,

/mjt



Bug#1130068: should not recommend libnss-winbind/libpam-winbind

2026-03-08 Thread Steinar H. Gunderson
Package: samba-ad-dc
Version: 2:4.22.6+dfsg-0+deb13u1
Severity: normal

Hi,

If you do as the trixie release notes say, and “apt install samba-ad-dc”
on your DC upgrade, you will (more or less silently) get libnss-winbind
and libpam-winbind on your DC. This means that by default (i.e., unless
you add some extra restrictions somewhere), every user on your domain
can log into your DC. 

This is an unusual configuration; pretty much every DC I've seen is
set up separated from normal users for security reasons. And given that
the main samba package does _not_ have such a Recommends (winbind itself
has a Suggests, which sounds like the right thing to me), I'm not sure
why samba-ad-dc specifically would have it? It doesn't seem to fit with
what Recommends generally means in Policy (“The Recommends field should
list packages that would be found together with this one in all but unusual
installations”; I would assume _installing_ them is the unusual setup).
Of course you can install them and then set up e.g. group ACLs in
sshd_config, but it's not obvious to me why this should be the default
setup.

I must admit I don't even understand why winbind is needed to run a DC,
but I'm sure there is some internal Samba reason, given that it is a
Depends. :-)

-- System Information:
Debian Release: 13.3
  APT prefers stable-security
  APT policy: (500, 'stable-security'), (500, 'stable-debug'), (500, 
'proposed-updates'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.18.2 (SMP w/56 CPU threads; PREEMPT)
Locale: LANG=en_DK.UTF-8, LC_CTYPE=en_DK.UTF-8 (charmap=UTF-8), 
LANGUAGE=en_NO:en_US:en_GB:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages samba-ad-dc depends on:
ii  init-system-helpers  1.69~deb13u1
ii  libbsd0  0.12.2-2
ii  libc62.41-12+deb13u2
pn  libldb2  
ii  libpopt0 1.19+dfsg-2
ii  libtalloc2   2:2.4.3+samba4.22.8+dfsg-0+deb13u1
pn  libtevent0t64
ii  python3  3.13.5-1
pn  python3-dnspython
pn  python3-samba
pn  samba
pn  samba-dsdb-modules   
pn  samba-libs   
pn  winbind  

Versions of packages samba-ad-dc recommends:
pn  libnss-winbind  
pn  libpam-winbind  
ii  python3-gpg 1.24.2-3
pn  samba-ad-provision  

Versions of packages samba-ad-dc suggests:
pn  bind9 
pn  bind9utils
pn  ldb-tools 
ii  ntpsec [time-daemon]  1.2.3+dfsg1-8