Hi Andrew,
   I got to thinking about this conversation and there may be some confusion 
regarding the network trace I am requesting. I spoke with Richard Guthrie from 
Microsoft who is a colleague on my team. He too has a issue of yours in a 
common area. He received a trace from you for that issue.

The issue that I am working on is for the following information from you:

"The documentation in MS-KILE 3.4.5.1 on DCE_STYLE is very terse, and fails to 
clarify a few points, one of which is preventing interoperability with Windows 
Vista.

  The client MUST generate an additional AP reply message exactly as the server 
would ([RFC4120]
  section 3.2.4) as the final message to send to the server. In GSS terms, the 
client must return
  success and a message to the server. It is up to the application to deliver 
the message to the
  server.

  The server MUST receive the additional AP reply message and verify that the 
message is
  constructed correctly ([RFC4120] section 3.2.5).

What is unclear here is how the sequence numbers, exchanged in this message, 
are expected to be updated.  For example, with a WinXP clients, and 
arcfour-hmac-md5 encryption, the sequence number (as maintained by the client, 
and seen on the server) is unaffected by the receipt of this extra message.

In Heimdal's implementation here, we reset the sequence numbers after verifying 
the AP_REP at line 690.

http://git.samba.org/?p=samba.git;a=blob;f=source/heimdal/lib/gssapi/krb5/accept_sec_context.c;h=73b93ceba4c6bb472c546afd52981bcf13051173;hb=v4-0-test

However, when GSSAPI CFX is used, and therefore an AES key is negotiated by a 
Windows Vista client to a Samba4 server, the client seems to require that the 
remote (from the server's persective) sequence number be increased by 1.

(ie, adding 1 to r_seq_number at like 690 allows the next gss_unwrap to match 
the expected sequence number correctly, in the DRSUAPI bind portion of a Vista 
SP1 domain join).

Simiarly, you will note in line 606, that we must disable timestamp 
verification.

While the client code (like 663) is comparatively sane...
http://git.samba.org/?p=samba.git;a=blob;f=source/heimdal/lib/gssapi/krb5/init_sec_context.c;h=c455a5dc8b7246c0c8e795206be5b9c3db114cb8;hb=v4-0-test

It seems that this is more than a simple role reversal, and the docs need to be 
expanded to clarify this."

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

The network trace I am requesting would be for the above problem with respect 
to the sequence numbers. I take it that it faults when the client doesn't 
receive the expected sequence number? If that is indeed the case then that 
would be the trace I am interested in seeing.

I hope this helps to clarify my request.

Thanks
John


-----Original Message-----
From: Andrew Bartlett [mailto:[EMAIL PROTECTED]
Sent: Monday, July 28, 2008 6:39 PM
To: John Dunning
Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED]
Subject: Re: Regarding [MS-KILE] 3.4.5.1 Three-Leg DCE-Style Mutual 
Authentication

On Mon, 2008-07-28 at 15:31 -0700, John Dunning wrote:
> Hello Andrew,
>
>    I wanted to touch bases with you to let you know that I am
> researching your question. In your email you indicated that Windows XP
> seems to take care of the sequence numbers correctly and I wanted to
> make sure I understood this. Are you saying that you are only seeing
> this behavior with Vista? Would it be possible for you to obtain a
> network trace of the case where it fails; when you don't add 1 to the
> sequence number around line 690 of your code?

That is the trace already supplied.  (As we fault anyway, just a few
more lines down the gsskrb5_unwrap() processing, , because we don't
match the checksum, even if we match the sequence number)

Andrew Bartlett
--
Andrew Bartlett                                http://samba.org/~abartlet/
Authentication Developer, Samba Team           http://samba.org
Samba Developer, Red Hat Inc.                  http://redhat.com

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