Smartcard logon over Terminal Services ( RDP redirection ) pII ( vista FYI )

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It seems I do spend a fair bit of time with smartcards lately, but I have some other interesting posts planned as well. Anyway, this is kind of a heads up to an interesting issue with Vista.

 

We changed some of the way things work ( for the better ) in Vista. You may have noticed that scredir.dll no longer exists in Vista - much of that code was moved into Winscard.dll. We also changed the way we call the CSP previously ( see https://blogs.msdn.com/spatdsg/archive/2006/10/06/Smartcards-and-cached-logons_2E002E002E00_.aspx ) we called from LSASS into winlogon.exe but we no longer do this in Vista - we go straight to the CSP.

Anyway - this post is marginally related to my other post Smartcard logon over Terminal Services ( RDP redirection )

Remember that the "server" will call back to the client via the RDP protocol ( virtual channel ) and MSTSC.EXE loads winscard.dll on the client in order to process these IO requests. Well in this case the calls never made it up to that level of the code. In fact, they died in the RDP client.

If you have a CSP which calls SCardUIDlgSelectCardW, it may fail due to this issue. The RDP session is initaited from Vista...

Vista --> Vista : works OL

Vista --> XP: FAILURE

XP--> XP: works OK

XP--> Vista : works OK

 

Error on XP:

 

Event Type: Failure Audit

Event Source: Security

Event Category: Logon/Logoff

Event ID: 537

Date: 3/27/2007

Time: 12:32:26 PM

User: NT AUTHORITY\SYSTEM

Computer: XPDEBUG

Description:

Logon Failure:

  Reason: An error occurred during logon

  User Name:

  Domain:

  Logon Type: 10

  Logon Process: User32

  Authentication Package: Kerberos

  Workstation Name: XPDEBUG

  Status code: 0xC000006D à STATUS_LOGON_FAILURE

  Substatus code: 0xC0000321 -> STATUS_SMARTCARD_SUBSYSTEM_FAILURE

 

Anyway - I hate leaving people in the dark with issues they may assume are due to the ISV's software .. so, even tho no fix is out yet... I have this FYI.

 

Fix is pending.. but again, if the behavior isnt changed, dont shoot the messenger.

 

[added on July 10,2007 ]Whooo hooo! It was fixed -public KB article is coming but if you need the fix now ask for the fix for article 939682

 

spatdsg