Hi,

There is an initial dissector for SCSI OSD in current SVN that
dissects some CDBs.

While implementing this i uncovered some flaws with the iscsi
dissector that did not handle AHS properly,   but it should work now.


There is still a bug in the iscsi dissector where it fails to
automatically detect that there is a HEADER DIGEST provided in the
PDU,   which leads to the dissector of DATA IN/OUT starting off at the
wrong offset (4 bytes to early).


I can not look into this HEADER DIGEST autodetection regression right
now  so for the time being I would suggest just focusing on the CDBs
and ignoring the DATA dissection.


I will look into why the autodetection doesnt work later.



A temporary workaround for this issue is to force the iscsi dissector
to always use crc32 header digests  which can be done by changing the
line (in packet-iscsi.c)

iscsi_session->header_digest=ISCSI_HEADER_DIGEST_AUTO;

into

iscsi_session->header_digest=ISCSI_HEADER_DIGEST_CRC32;





On 9/29/06, Joe Breher <[EMAIL PROTECTED]> wrote:
> Ronnie -
>
> Some example traces should be in your personal inbox. I need to do some
> checking to see whether I am at liberty to release them to the public at
> large. I'll find some way to make that happen.
>
> For those who may be following along:
>
> I guess I've committed to the task of adding some SCSI-OSD-specific info
> to the wiki. I've never edited a wiki before, so please be patient.
>
> It sounds like Ronnie may be willing to at least advise me on design
> decisions within the SCSI dissector - or perhaps even actively
> contribute to the coding. Such would be very appreciated, as I do not
> yet know where to start on this task.
>
> ronnie sahlberg wrote:
> > Hi,
> >
> > Since there are many opcodes in OSD that are from SPC I think the best
> > solution would probably be to
> > implement everything except opcode 0x7f in the existing dissector  and
> > implement the OSD specific bits (opcode 0x7f)
> > in a new packet-scsi-osd.c
> >
> >
> > Adding an initial dissector for OSD that at least includes all the
> > opcodes that are shared from SPC would be trivial and I can do that
> > tonight.
> >
> >
> > Do you have example captures with OSD traffic you can share?
> >
> >
> >
> >
> > On 9/28/06, *Joe Breher* <[EMAIL PROTECTED]
> > <mailto:[EMAIL PROTECTED]>> wrote:
> >
> >     With much embarrassment, I note that I neglected to change the Subject
> >     of my last post (quoted herein). This reply should be near my last
> >     post
> >     in the digest, thereby hopefully eliminating some confusion.
> >
> >     Joe Breher wrote:
> >     > ronnie sahlberg wrote:
> >     >
> >     >> Please do so. It would be very nice to add one more transport
> >     for our
> >     >> SCSI dissector.
> >     >>
> >     >>
> >     > Ronnie (et al) -
> >     >
> >     > It may be time for me to go public with the reason for my desire to
> >     > become involved with wireshark development. In essence, I am in
> >     need of
> >     > a dissector for SCSI-OSD. This is an INCITS T10 Technical Committee
> >     > ratified Standard for a command set for Object-based Storage
> >     Devices.
> >     > This is a full command layer as SBC, SMC, etc, that are already
> >     > supported in the wireshark SCSI dissector.
> >     >
> >     > I still am not familiar enough with the wireshark SCSI dissector
> >     code to
> >     > have opinions on the matter. Accordingly, now is probably an
> >     opportune
> >     > time for discussion ;-).
> >     >
> >     > It is unclear to me at this point whether it makes more sense to
> >     extend
> >     > the current SCSI dissector, or to develop a new one for OSD. I'd
> >     like to
> >     > extend the current one. However, there are several unique
> >     challenges in
> >     > OSD that do not exist in any of the command sets that the current
> >     > dissector in packet-scsi.c currently handles. Among these are :
> >     > - Variable Length CDBs
> >     > - 'opcode' is x7F for all commands - the 'effective opcode' is
> >     actually
> >     > a two-byte Service Action in bytes CDB[9..8]
> >     > - bidirectional data transfers - Data In *and* Data Out 'phases'
> >     ('IUs',
> >     > 'PDUs', whatever) during the execution of a *single* command.
> >     > the list goes on.
> >     >
> >     > I would love to hear from anyone who either has an interest in these
> >     > aspects of SCSI, or has insight into the design decisions behind the
> >     > current SCSI dissector.
> >     > _______________________________________________
> >     > Wireshark-dev mailing list
> >     > [email protected] <mailto:[email protected]>
> >     > http://www.wireshark.org/mailman/listinfo/wireshark-dev
> >     <http://www.wireshark.org/mailman/listinfo/wireshark-dev>
> >     >
> >
> >     _______________________________________________
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> >     [email protected] <mailto:[email protected]>
> >     http://www.wireshark.org/mailman/listinfo/wireshark-dev
> >
> >
> > ------------------------------------------------------------------------
> >
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> >
>
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