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<p class="MsoNormal"><span style="font-family:"Courier New";color:black">Nadezhda Ivanova,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:black">Someone from our team will follow-up with you shortly in regards to your questions.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:black">Dominic Salemno<br>
Escalation Engineer<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:black">Open Specifications<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New";color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> didrash@gmail.com [mailto:didrash@gmail.com]
<b>On Behalf Of </b>Nadezhda Ivanova<br>
<b>Sent:</b> Friday, December 17, 2010 6:08 AM<br>
<b>To:</b> Interoperability Documentation Help<br>
<b>Cc:</b> cifs-protocol@samba.org<br>
<b>Subject:</b> Questions about Validated-SPN validated write<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt">Hello,<br>
Does Validated-SPN validated write allow an account to set an object's SPN to the following values:<br>
HOST/samAccountName (without the "$")<br>
HOST/dnsDomainName<br>
if the object is a regular computer object and NOT a DC?<br>
<br>
The algorithm described in MS-DRSR 5.5 AccessCheckWriteToSpnAttribute seems to indicate that yes, this should be allowed. Ot the other hand, MS-ADTS 3.1.1.5.3.1.1.4 servicePrincipalName leads me to believe that the object being a DC is mandatory constraint:
"The SPN is a syntactically correct two-part SPN, or it is a syntactically correct three-part SPN (see<br>
Mutual Authentication (section 5.1.1.4)) and the object is a DC’s domain controller object (see<br>
sections7.1.1.3.1 and 7.1.1.3.2). "<br>
<br>
In addition, I did the following test:<br>
Gave Validated-SPN right to a user on a regular computer object, and got CONSTRAINT_VIOLATION when setting its servicePrincipalName with the above described values.<br>
Gave Validated-SPN right to a user on a DC object, and these values were set successfully.<br>
<br>
So my questions are:<br>
Is the behaviour of setting servicePrincipalName supposed to be different between LDAP and DRS?<br>
Does servicePrincipalName modification depend on things other then the syntax restrictions described in MS-DRSR and MS-ADTS?<br>
If an object does not have Validated-SPN on Principal-Self, should the account still be allowed to set the above values via DRS?<br>
<br>
Best Regards,<br>
Nadezhda Ivanova<o:p></o:p></p>
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