(Classic ASP) Get Certificate User Principal Name (UPN)

See more Certificates Examples

Demonstrates how to get a certificate's UPN from the SAN (Subject Alternative Name). Most certificates do not have a UPN. This example only applies to those certificates that have a User Principal Name.

Note: This example requires Chilkat v9.5.0.90 or greater due to fixes made in getting the UPN from the SAN.

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Cert")
set cert = Server.CreateObject("Chilkat.Cert")

success = cert.LoadFromFile("qa_data/certs/sample.cer")
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( cert.LastErrorText) & "</pre>"
    Response.End
End If

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Xml")
set xml = Server.CreateObject("Chilkat.Xml")
success = xml.LoadXml(cert.SubjectAlternativeName)
Response.Write "<pre>" & Server.HTMLEncode( xml.GetXml()) & "</pre>"

' A certificate with a User Principal Name in the SAN might have this:

' <SubjectAltName>
'     <rfc822Name>joe@example.com</rfc822Name>
'     <name type="oid" oid="1.3.6.1.4.1.311.20.2.3">joe@example.com</name>
' </SubjectAltName>

' The OID 1.3.6.1.4.1.311.20.2.3 is for the User Principal Name.
upn = xml.ChilkatPath("/A/name,oid,1.3.6.1.4.1.311.20.2.3|*")
If (xml.LastMethodSuccess = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( "No user principle name.") & "</pre>"
Else
    Response.Write "<pre>" & Server.HTMLEncode( "User Principle Name = " & upn) & "</pre>"
End If


%>
</body>
</html>