Q238143: BUG: WTSQuerySessionInformation() Returns Invalid Client Address

Article: Q238143
Product(s): Microsoft Windows NT
Version(s): 4.0
Operating System(s): 
Keyword(s): kbnetwork kbAPI kbOSWin2000 kbOSWin2000bug kbSDKPlatform kbSDKWin32 kbDSupport kbGrpDSN
Last Modified: 10-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 4.0 
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SYMPTOMS
========

You should use the WTSQuerySessionInformation function with the filtering flag,
WTSClientAddress, to get the client IP address on a Windows Terminal Client. The
buffer that is returned by this function contains a WTS_CLIENT_ADDRESS structure
for the client address family and address. However, on Windows NT Server version
4.0, Terminal Server Edition (TS4), the client address field is invalid.

RESOLUTION
==========

As a workaround on TS4, you can first use the WTSQuerySessionInformation
function with the WTSClientName filtering flag to get the client name. The
client name is either a dotted IP address or a name string. If the client name
is a name string, use the gethostbyname function to resolve the name to an IP
address.

The following code fragment illustrates how to use the gethostbyname function to
resolve a client name string to its IP address:

     ...
     ...
     ...
     lphp = gethostbyname(szClientName);

     if (lphp == NULL)
     {
        printf("gethostbyname failed: %d", WSAGetLastError());
        return -1;
     }

     inAddr.s_addr = ((struct in_addr far *)(lphp->h_addr))->s_addr;
     printf("Client address: %s\n", inet_ntoa(inAddr));
     ...
     ...
     ...

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products that are
listed at the beginning of this article.

MORE INFORMATION
================

Because of this bug, both the auditing event log and tsadmin do not show the IP
address of the client.

Additional query words:

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Keywords          : kbnetwork kbAPI kbOSWin2000 kbOSWin2000bug kbSDKPlatform kbSDKWin32 kbDSupport kbGrpDSNet 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : :4.0
Issue type        : kbbug
Solution Type     : kbnofix

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