computer account change password with Windows 2008 domain

[Russ Allbery]

Ross, could you give Tim our reference numbers for our Microsoft bug
reports that we filed as part of Guest?  They're running into one of the
same issues, and I figure the more the merrier on the complaining.

"Tim Alsop" <Tim.Alsop at CyberSafe.Com> writes:

> Russ,
>
> That's great information, thanks.
>
> We are using Kerberos set password protocol to change/set the computer
> account password, but since the SPN used contains a / I suspect we are
> experiencing the same issues you described.
>
> If you have any reference numbers for your problems, then I would like
> to mention them to MS when I talk to them tomorrow. 
>
> Thanks,
> Tim
>
> -----Original Message-----
> From: Russ Allbery [mailto:rra at stanford.edu] 
> Sent: 01 April 2008 22:17
> To: Tim Alsop
> Cc: kerberos at mit.edu
> Subject: Re: computer account change password with Windows 2008 domain
>
> "Tim Alsop" <Tim.Alsop at CyberSafe.Com> writes:
>
>> We have discovered a problem when we try to set/change password for a
>> computer account in AD on Windows Server 2008. The computer account is
>> created so we can use it for a service/application, and the key is
>> created from it's password (randomly generated) and extracted into a
> key
>> table file.
>>
>> Our code is able to create the account (authenticating to AD using
>> SASL/GSS/Kerberos) but when we try and set the computer account's
>> password to a random value, the request is rejected, so it looks like
> AD
>> on Windows 2008 has some changes which stop password changes for
>> computer accounts, or maybe something which is stopping changes to
>> passwords for accounts that use a principal name such as
>> name/fqdn at REALM.
>
> You don't say here *how* you're changing the password, but there are two
> Active Directory bugs in Windows 2008 that you may be running into:
>
> * Authentication to Active Directory using a principal that contains a
>   slash (such as service/foo) from a keytab generated by the Windows
> tool
>   is broken in Windows 2008.  It works fine if there is no slash in the
>   principal.  Microsoft has identified this as a bug and is working on a
>   fix.
>
> * Microsoft broke password changes via the LDAP protocol with SASL
> GSSAPI
>   binds in Windows 2008.  In Windows 2003, provided that you didn't try
> to
>   negotiate an SASL privacy layer, you could connect via TLS and
>   authenticate with GSSAPI and query or set the password attribute
>   directly.  In Windows 2008, this no longer works; you always get the
>   error from the server that you are not permitted to negotiate a
> privacy
>   layer when using TLS, even though you're not trying to.  We've already
>   filed this as a bug.
>
> In both cases, if you have a support contract with Microsoft and this is
> a
> problem that you're running into, please independently open your own
> bug;
> the more customers they know this affects, the more likely we'll get a
> hot
> fix.

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>