RR_TYPE_NULL

[Christopher R. Hertel]

Digging further...

Positive responses:  When the query is directed to an end node (recursion
                     desired is false) the behavior is correct.  Samba does
                     return type NB.  From the code, it appears that Samba
                     sends back a NULL type if the query is sent to an NBNS.
                     I haven't tested this, however.

Negative Responses:  XP Pro returns type NB but the RFC says NULL.  I think
                     Samba's okay returning NULL even though it doesn't
                     match Windows.

              WACK:  The RFC is self-contradictory, and Windows returns NB.

Generally speaking, I haven't seen the RR_TYPE_NULL used by Windows systems
at all.  Though it somewhat contradicts RFC 1002 (which also contradicts
itself with regard to the WACK), the use of the RR_TYPE_NB across the board
does make some sense since all of these packets are NetBIOS ("NB") related.

Chris -)-----

Christopher R. Hertel wrote:
> In nmbd_packets.c: reply_netbios_packet() the RR_TYPE_NULL (0x000a) type is
> used for a variety of query response packets.  I don't think that this is
> correct, and I know it doesn't match what I see from Windows systems.
> 
> In a positive query response the RR_TYPE should be NB (0x0020), not NULL.
> 
> For a negative name query response, RFC1002 says that RR_TYPE_NULL should be
> used but Windows returns RR_TYPE_NB and so do older versions of Samba.
> 
> For a WACK, the RFC is unclear.  The diagram in section 4.2.16 says "NULL
> (0x0020)", which is obviously a contradiction.  I have some old captures I
> did while writing my book that show a Windows WINS server sending back type
> NB (0x0020).
> 
> At minimum, the positive name query response should be sending back type NB,
> not NULL.  The query reply information is stored in a type NB structure.
> 
> 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