When was 'session setup' introduced? (propose to change server-side min protocol to match)

Christopher R. Hertel crh at samba.org
Wed May 30 10:42:19 MDT 2012

On 05/30/2012 10:52 AM, Jeremy Allison wrote:
> On Wed, May 30, 2012 at 03:57:40PM +1000, Andrew Bartlett wrote:
>> On Wed, 2012-05-30 at 07:50 +0200, Volker Lendecke wrote:
>>> On Wed, May 30, 2012 at 03:46:26PM +1000, Andrew Bartlett wrote:
>>>> On Tue, 2012-05-29 at 21:24 -0500, Christopher R. Hertel wrote:
>>>>> SessionSetupAndX was introduced in LAN Manager v1.0, the first OS/2 version
>>>>> of the protocol.  The Core Protocol does not support SessionSetupAndX.  See:
>>>>> http://msdn.microsoft.com/en-us/library/ee442101
>>>>> You do realize that this is the first time ever that we will have disabled
>>>>> support for a dialect.  ...and that Windows servers still support this dialect.
>>>> Very interesting.  How does that work?
>>>> In any case, it won't work in Samba, so I propose this.
>>> We might need to revive the code and fix bugs, but many
>>> people will be very unhappy about that. The problem is that
>>> there are still disk imagers in use that are dos-based,
>>> fetching the restore images from SMB via the ancient ms-tcp
>>> dos redirector.
>> When I last used the DOS SMB client (yes, I've used it for imaging too),
>> it was using a modern enough protocol version to be logging in with a
>> username/password.
>> Do you have a network trace of a failing case?
> I think you are correct here. The last time I used the DOS
> client it did indeed do a sessionsetup call.

Many of the OS/2 LAN Manager dialects had DOS equivalents, so I don't think 
that there will be problems with DOS-based systems.  The DOS version of the 
LAN Manager 1.0 dialect was "MICROSOFT NETWORKS 3.0", and the DOS version of 
LAN Manager 2.1 was "DOS LANMAN2.1".

It is worth noting that the Core Protocol does not define the Flags field 
and does not even set the Reply bit in the SMB response.  Wireshark can't 
properly parse an SMB Core Protocol exchange, because it is expecting that 
Reply bit.  I doubt that anyone is using Core Protocol in production.

I have been in contact recently with someone who is, for research purposes, 
testing the original DOS redirector (thanks, Michal!).  It still runs in 
modern DOS systems and Windows still supports it properly.  I have a trace 
or two, and I could ask whether or not it runs correctly against Samba.

Chris -)-----

"Implementing CIFS - the Common Internet FileSystem" ISBN: 013047116X
Samba Team -- http://www.samba.org/     -)-----   Christopher R. Hertel
jCIFS Team -- http://jcifs.samba.org/   -)-----   ubiqx development, uninq.
ubiqx Team -- http://www.ubiqx.org/     -)-----   crh at ubiqx.mn.org
OnLineBook -- http://ubiqx.org/cifs/    -)-----   crh at ubiqx.org

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