HSE_REQ_GET_CERT_INFO_EX Is Not Exposed in ISAPI ServerSupportFunction (221514)

SYMPTOMS

In Microsoft Internet Information Server (IIS) 4.0, several new options have been added to the ServerSupportFunction. The ServerSupportFunction is a callback function that is supplied in the ECB (EXTENSION_CONTROL_BLOCK). It supports several auxiliary functions that are not covered by other explicit callback functions in the ECB. One of these new options is HSE_REQ_GET_CERT_INFO_EX, which returns a CERT_CONTEXT structure. This option is currently only exposed to ISAPI Extensions, so when writing an ISAPI Filter, this call may fail and may not return a CERT_CONTEXT structure as expected.

RESOLUTION

Windows NT Server or Workstation 4.0

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:

http://www.microsoft.com/windows/servicepacks/ -or-
152734 how to obtain the latest windows nt 4.0 service pack

For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://support.microsoft.com/directory/overview.asp

Windows NT Server 4.0, Terminal Server Edition

To resolve this problem, obtain the latest service pack for Windows NT Server 4.0, Terminal Server Edition. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

152734 How to Obtain the Latest Windows NT 4.0 Service Pack

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows NT Server version 4.0, Terminal Server Edition Service Pack 6.

MORE INFORMATION

The following code can be used to obtain a client certificate in the ISAPI Filter:

char CertificateBuf[8192];
CERT_CONTEXT_EX ccex;
ccex.cbAllocated = sizeof(CertificateBuf);
ccex.CertContext.pbCertEncoded = (BYTE*)CertificateBuf;
DWORD dwSize = sizeof(ccex);

   if (pfc->ServerSupportFunction(pfc,
 (enum SF_REQ_TYPE)HSE_REQ_GET_CERT_INFO_EX,                               
 (LPVOID)&ccex, dwSize,NULL) == FALSE)
   {
// Handle Error Here
   }
   // ccex now contains valid client certificate information.