[cifs-protocol] [REG:118040517948537] MS-ADTS: msDS-ResultantPSO and DOMAIN_USER_RID_KRBTGT discrepancy

Wed Apr 25 20:50:27 UTC 2018

Hi Obaid,

Thank you for clarifying the expected behaviour. That makes sense.

Cheers,
Tim

On 25/04/18 04:54, Obaid Farooqi wrote:
> Hi Tim:
> The code actually intends to not return msDS-ResultantPSO when RID is equal to that of krbtgt but due to a bug, the comparison fails and instead of nothing, the msDS-ResultantPSO is returned. I tested against WS2012R2. The code is identical from Vista (WS2008) till Ws2012R2. I have not checked against WS2016 yet. 
>
> I have filed a bug against MS-ADTS to fix this issue.
>
>
> Regards,
> Obaid Farooqi
> Escalation Engineer | Microsoft
>
> Exceeding your expectations is my highest priority.  If you would like to provide feedback on your case you may contact my manager at ramagane at Microsoft dot com
>
> -----Original Message-----
> From: Tim Beale <timbeale at catalyst.net.nz> 
> Sent: Monday, April 9, 2018 12:12 AM
> To: Obaid Farooqi <obaidf at microsoft.com>
> Cc: cifs-protocol at lists.samba.org; MSSolve Case Email <casemail at microsoft.com>
> Subject: Re: [REG:118040517948537] MS-ADTS: msDS-ResultantPSO and DOMAIN_USER_RID_KRBTGT discrepancy
>
> Hi Obaid,
>
> You can reproduce the problem by doing the following:
>
> - Create a new msDS-PasswordSettings object. E.g.
> https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fblogs.technet.microsoft.com%2Fcanitpro%2F2013%2F05%2F29%2Fstep-by-step-enabling-and-using-fine-grained-password-policies-in-ad%2F&data=02%7C01%7Cobaidf%40microsoft.com%7C9e0e2771473540762c9508d59dd85fb4%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636588475007318631&sdata=iztmo%2BfkcSggbJe%2FxTDmIA4ZW75noVaDRW%2FfRbvxA4k%3D&reserved=0
> or a more out-dated approach using ADSI Edit (which I think I used
> originally)
> https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fblogs.technet.microsoft.com%2Fseanearp%2F2007%2F10%2F06%2Fwindows-server-2008-fine-grained-password-policy-walkthrough%2F&data=02%7C01%7Cobaidf%40microsoft.com%7C9e0e2771473540762c9508d59dd85fb4%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636588475007318631&sdata=3%2FkmbCFEDopECsTsyKvtgV%2FtRNX9UBru7G5QJqbJ57c%3D&reserved=0
> - Apply the PSO to the krbtgt user. I did this by opening ADSI Edit,
> right-clicking on the PSO created in the previous step, select
> 'Properties', then edit the msDS-PSOAppliesTo attribute. I used the 'Add
> DN' option and just pasted in the DN of the krbtgt user (then click
> 'OK', and 'Apply').
> - Check the Resultant PSO. i.e. In ADSI Edit, right-click on the krbtgt
> user, select 'Properties', then look for the msDS-ResultantPSO attribute.
>
> I've actually been testing this as part of Samba development by using a
> python test script that connects to the Windows DC over LDAP and does
> the above steps as LDIF operations. So you can probably reproduce the
> first 2 steps just by applying an LDIF (tentative example follows, but I
> haven't tried using exactly this approach myself).
>
> dn: CN=test-PSO,CN=Password Settings Container,CN=System,DC=<your-domain>
> changetype: add
> objectClass: msDS-PasswordSettings
> msDS-PasswordSettingsPrecedence: 2
> msDS-PasswordReversibleEncryptionEnabled: FALSE
> msDS-PasswordHistoryLength: 10
> msDS-PasswordComplexityEnabled: TRUE
> msDS-MinimumPasswordLength: 10
> msDS-MinimumPasswordAge: 0
> msDS-MaximumPasswordAge: -25920000000000
> msDS-LockoutThreshold: 0
> msDS-LockoutObservationWindow: -50000000
> msDS-LockoutDuration: -50000000
> msDS-PSOAppliesTo: CN=krbtgt,CN=Users,DC=<your-domain>
>
> Cheers,
> Tim
>
> On 07/04/18 08:27, Obaid Farooqi wrote:
>> Hi Tim:
>> Can you please let me know the step you took to add this object and applied to krbtgt?
>>
>> Regards,
>> Obaid Farooqi
>> Escalation Engineer | Microsoft
>>
>> Exceeding your expectations is my highest priority.  If you would like to provide feedback on your case you may contact my manager at ramagane at Microsoft dot com
>>
>> -----Original Message-----
>> From: Obaid Farooqi 
>> Sent: Friday, April 6, 2018 12:48 PM
>> To: 'Tim Beale' <timbeale at catalyst.net.nz>
>> Cc: cifs-protocol at lists.samba.org; MSSolve Case Email <casemail at microsoft.com>
>> Subject: RE: [REG:118040517948537] MS-ADTS: msDS-ResultantPSO and DOMAIN_USER_RID_KRBTGT discrepancy
>>
>> Hi Tim:
>> I'll help you with this issue and will be in touch as soon as I have an answer.
>>
>> Regards,
>> Obaid Farooqi
>> Escalation Engineer | Microsoft
>>
>> Exceeding your expectations is my highest priority.  If you would like to provide feedback on your case you may contact my manager at ramagane at Microsoft dot com
>>
>> -----Original Message-----
>> From: Obaid Farooqi 
>> Sent: Friday, April 6, 2018 12:47 PM
>> To: "'Tim Beale'" <timbeale at catalyst.net.nz>
>> Cc: "cifs-protocol at lists.samba.org" <cifs-protocol at lists.samba.org>; "MSSolve Case Email" <casemail at microsoft.com>
>> Subject: [REG:118040517948537] MS-ADTS: msDS-ResultantPSO and DOMAIN_USER_RID_KRBTGT discrepancy
>>
>> Hello Tim 
>>
>> We have created a case; 118040517948537, to track your inquiry and an Escalation Engineer will contact you to assist further.
>>
>> Best Regards,
>> Tarun Chopra | Sr. Escalation Engineer
>> Open Specifications Support Team
>> Work +1-425-705-5042
>> Email  tarun.chopra at microsoft.com
>> Monday-Friday 9:00a-6:00p Pacific Timezone 
>>
>> -----Original Message-----
>> From: Tim Beale <timbeale at catalyst.net.nz>
>> Sent: Thursday, April 5, 2018 2:00 PM
>> To: Interoperability Documentation Help <dochelp at microsoft.com>; cifs-protocol at lists.samba.org
>> Subject: MS-ADTS: msDS-ResultantPSO and DOMAIN_USER_RID_KRBTGT discrepancy 
>>
>> Hi, 
>>
>> I'm looking into the behaviour of msDS-ResultantPSO and found a discrepancy between the specification and the actual behaviour.
>>
>> In MS-ADTS, section 3.1.1.4.5.36 msDS-ResultantPSO [1], it says the
>> following: 
>>
>>   If the RID in U!objectSid is equal to DOMAIN_USER_RID_KRBTGT, then there is no value in this attribute. 
>>
>> I tried adding a PSO object and applying it to the krbtgt user on a Windows 2012R2 VM. Based on the spec, I would expect no msDS-ResultantPSO to be returned for the krbtgt user. However, I do see one returned, e.g.
>>
>> # record 1
>> dn: 
>> CN=krbtgt,CN=Users,DC=WINDOWS2012R2,DC=WIN,DC=TIM,DC=WGTN,DC=CAT-IT,DC=
>> CO,DC=NZ
>> objectSid: S-1-5-21-886655096-618523297-2770022155-502
>> msDS-ResultantPSO: CN=dummy-PSO,CN=Password Settings Container,CN=System,DC=WINDOWS2012R2,DC=WIN,DC=TIM,DC=WGTN,DC=CAT-IT,DC=
>> CO,DC=NZ
>>
>> You can see the RID in the objectSid is 502, which is DOMAIN_USER_RID_KRBTGT. 
>>
>> Could you please clarify which is incorrect - the specification or the Windows behaviour? Or have I misunderstood something?
>>
>> Thanks,
>> Tim 
>>
>> [1]
>> https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmsdn.mi
>> crosoft.com%2Fen-us%2Flibrary%2Fcc223866.aspx&data=02%7C01%7Cdochelp%40w
>> indows.microsoft.com%7Ce172420a92714a01130f08d59b383228%7C72f988bf86f141
>> af91ab2d7cd011db47%7C1%7C0%7C636585588018722990&sdata=KdE0SNnF0Xy3GBjnp8
>> UKzXt4GB9xQ2j0fFKuUZaD9JI%3D&reserved=0
>>
>>