[jcifs] username dialog syntax changes

John Engilis JohnE at vacationsonly.com
Tue Mar 28 17:49:09 GMT 2006

Hey Rich,

This was very helpful for me. I've been having difficulty authenticating
to a Windows 2003 Domain Controller for the past 2 weeks.

I've attempted to specify the domain, wins server and domain controller
as well as do pre-authentication.  The domain and wins alone would give
me an unknown host error.  I surmised that it may have been an issue
with our network.  But I have yet to locate any problems.  Attempting to
specify the full domain name and not the NT domain resulted in the same
error, but the full domain name was being truncated (it's 17 characters
counting the .com;  I believe the last character or 2 were being cut
off).  Since the domain was not resolving, the username and password for
pre-authentication was not working.

I've been using version 1.1.11 because it was actually allowing users to
connect to our Intranet.  The first user could get in without an error.
Most subsequent users would get an error message (invalid signature or
something to that effect) the first time, but could then get in after
refreshing.  The later version of jcifs (1.2.7) caused the
authentication dialog box to pop up and even when correct credentials
were entered it would not authenticate and allow users to see our
Intranet (using NT domain or the full domain name).  Setting the
jcifs.smb.client.ssnLimit to 1 as mentioned at jcifs.samba.org made it
worse locking it up or again producing the dialog box that wouldn't
authenticate (depending on the version of jcifs).

Referencing your email, I eliminated the jcifs.smb.client.domain and
changed the username to user at domain.com.  With that simple change I was
able to do pre-authenticating and have each user connect every time
without fail.

John Engilis 
Project Coordinator / Programmer 
john.engilis at vacationsonly.com 

-----Original Message-----
From: jcifs-bounces+johne=vacationsonly.com at lists.samba.org
[mailto:jcifs-bounces+johne=vacationsonly.com at lists.samba.org] On Behalf
Of Richard Caper
Sent: Monday, March 27, 2006 3:41 PM
To: Michael B Allen
Cc: Tapperson Kevin; jcifs at lists.samba.org
Subject: Re: [jcifs] username dialog syntax changes

I poked around with this awhile back... from what I recall the current
jCIFS actually works with some finagling.  From what I remember:

1) specifying "jcifs.smb.client.username" as the full kerberos-style
username with no jcifs.smb.client.domain specified works; i.e.
username = "bob at my.domain.com".

2) specifying "jcifs.smb.client.username" as the account username and
the full kerberos style realm as jcifs.smb.client.domain works.  i.e.
username = "bob" and domain = "my.domain.com".

3) specifying "jcifs.smb.client.username" as user at ntdomain also worked;
i.e. "bob at MYDOM" with no jcifs.smb.client.domain.

On 3/27/06, Michael B Allen <mba2000 at ioplex.com> wrote:
> On Mon, 27 Mar 2006 10:51:49 -0600
> "Tapperson Kevin" <Kevin.Tapperson at hcahealthcare.com> wrote:
> > >> > correct fix would be to use RFC 2052 SRV DNS lookups to find 
> > >> > the domain controller for the particular realm.
> > >>
> > >> In this case, what is the relationship then between a realm and a

> > >> domain.
> > >
> > >There is a 1:1 mapping between a user principal name and a SAM 
> > >account
> > name but the realm and domain are not required to >be the same. For 
> > example in a large company you might divide up your domains by 
> > department with a single realm.
> >
> > So, if I understand correctly, the <userid>@<domain> syntax is 
> > really just using the userPrincipalName attribute from AD.  And the 
> > userPrincipalName is composed of <sAMAccountName>@<realm>.
> >
> > It also appears from the packet captures that I had originally sent 
> > with this thread that the realm can be abbreviated.  The user used 
> > in the packet caputres (ylp4565 at wintel) has a userPrincipalName 
> > attribute in AD of ylp4565 at wintel.certlab.net.  (The domain for this

> > user is wintel.)
> So maybe it looks like <sAMAccountName> ~= <userPrincipalName> and 
> <realm> and <domain> are interchangeable since you can always get the 
> realm from the domain. But I'm no expert by any measure. I don't 
> really know what the definitive rules are. Regardless, I think jcifs 
> would still need a considerable modification to allow the domain to be
converted to realm.
> Incedentally, your patch was NOT integrated into 1.2.8. I just didn't 
> feel like there was enough understanding about it yet (and I still
> Mike

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