Re: Samba's protocals (was 3 different OS)

[guenther+openbsd-misc@sendmail.com]

"David Hodnett" <dwar@earthlink.net> writes:
>I never got around to asking this question and I'm hoping I can get 
>a quick yes/no answer.  On the Samba web site, in the 
>"Introduction to Samba" FAQ, they have a section that details their 
>future plans.
>
>Paraphasing slightly, they said that with Microsoft Windows 2000, 
>Microsoft hopes to gradually phase out NetBIOS, and 
>consequently, the Samba team hopes to do so as well (and rely 
>strictly upon TCP/IP).  Obviously, Windows 2000 has been out for 
>years now and that part of the FAQ is outdated.

The whole subject is a mess, so let's define some terms.

NetBIOS is an architecture running network services, including naming
	services and an programming API.  It can be run directly on top
	of ethernet---in which it's called NetBEUI---or on top of other
	protocols including at least TCP/IP, IPX/SPX, and DECnet.
	
NetBEUI, as described above, is a network and transport layer protocol
	that runs directly on ethernet, parallel to IPX/SPX and TCP/IP.
	It has its own ethernet type code and it not routable, only
	bridgable.  Avoid this sucker like the plague.

NBT is a another name for NetBIOS on top of TCP/IP.  It uses ports 137,
	138, and 139 with both TCP and UDP and is at least partly
	documented in rfcs 1001 and 1002.

SMB is a protocol for file-sharing, printer-sharing, washing dishes and
	everything else MS thought to throw into it.  It was originally
	implemented as a service on top of NetBIOS.

CIFS is another name for SMB that MS starting using when it started
	trying to make SMB an Internet standard.  The CIFS draft specs
	explicitly state that CIFS does not depend on any specific
	transport protocol and describe how it might be run directly
	over TCP without the use of NetBIOS.

Give the above, the statement in the docs should make more sense.  All
version of Windows before Windows2000 only support SMB over NetBIOS.
Windows2000 supports both SMB over NetBIOS and SMB over TCP directly.
Samba currently only supports SMB with NetBIOS over TCP (NBT), though
they hope to add support for SMB over TCP.


>Question: can the latest version of Samba (version 2.2.1a) 
>packaged for OpenBSD 3.0, deliver full functionality using strictly 
>TCP/IP?

You'll have to decide what you mean by 'strictly TCP/IP'.  Samba doesn't
use any protocol 'parallel' to TCP/IP (so you don't need to let through
something besides TCP/IP), but it runs NetBIOS on top of that using TCP
and UDP ports 137-139.


>Reason: I'd really like to avoid installing NetBIOS on any of these 
>machines since I don't have the time to keep up with the security 
>holes in that protocal.

I can think of several interpretations of that sentence depending on
what you mean by 'NetBIOS'.  If the above isn't enough to answer your
question, could you rephrase it in more precise terms?  In particular,
don't use of the word 'NetBIOS' without qualifying whether you mean the
API, the service model, or an implementation of it over a specific
transport.


Philip Guenther
guenther@sendmail.com
ex-sysadmin, now software engineer