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[freetds] Multiple server challenge packets during NTLM authentication

From: Vipul Sharma <vipsharma.sharma AT gmail.com>
To: FreeTDS Development Group <freetds AT lists.ibiblio.org>
Subject: [freetds] Multiple server challenge packets during NTLM authentication
Date: Tue, 7 Jan 2014 20:37:50 +0530

Hello,

While running my tests using tsql client, i found that if server sends
multiple NTLM Challenge packets, then tsql generates a new NTLM AUTH packet
for every Challenge packet. The sequence is as follows :

Client -> Server (NTLM Negotiate packet)
Server -> Client (NTLM Challenge packet)
Client -> Server (NTLM AUTH packet)
Server -> Client (NTLM Challenge packet)
Client -> Server (NTLM AUTH packet)

Is this supported by NTLM protocol ? I tested the same sequence with other
TDS clients(SQL Server Studio) and it threw an error.

Is this a bug ? Can somebody please shed some light on this ?

Thanks,
Vipul

[freetds] Multiple server challenge packets during NTLM authentication, Vipul Sharma, 01/07/2014
- Re: [freetds] Multiple server challenge packets during NTLM authentication, Frediano Ziglio, 01/07/2014