Visual Basic 6.0

PKCS11 Certificate Chain

See more PKCS11 Examples

Demonstrates how to make CA certs available for the certificate chain to be included when creating a signature (using a PKCS11 compatible smart card / USB token) such as for PDF, XMLDSig, etc.

Note: This example requires Chilkat v9.5.0.88 or later.

Visual Basic 6.0

Dim success As Long
success = 0

' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

Dim pkcs11 As New ChilkatPkcs11

' You will use the DLL (or shared lib) provided by your smart card vendor, or a DLL compatible with your smart card.
' On Windows, if the DLL is located in C:\Windows\System32, specify only the filename.
' Otherwise provide the full path.
pkcs11.SharedLibPath = "bit4xpki.dll"

success = pkcs11.Initialize()
If (success = 0) Then
    Debug.Print pkcs11.LastErrorText
    Exit Sub
End If

' Pass -1 for the slotID to open a session on the first non-empty slot.
Dim slotID As Long
slotID = -1

' Open a session.
Dim readWrite As Long
readWrite = 1
success = pkcs11.OpenSession(slotID,readWrite)
If (success = 0) Then
    Debug.Print pkcs11.LastErrorText
    Exit Sub
End If

' Make it an authenticated session by calling Login.
Dim userType As Long
userType = 1
' Make sure to use the correct PIN for your smart card..
Dim pin As String
pin = "0000"
success = pkcs11.Login(userType,pin)
If (success = 0) Then
    Debug.Print pkcs11.LastErrorText
    success = pkcs11.CloseSession()
    Exit Sub
End If

' Get the certificate (on the smart card) that has a private key.
Dim cert As New ChilkatCert
success = pkcs11.FindCert("privateKey","",cert)
If (success = 1) Then
    Debug.Print "Cert with private key: " & cert.SubjectCN
Else
    Debug.Print "No certificates having a private key were found."
    success = pkcs11.CloseSession()
    Exit Sub
End If

' If the certificates in the chain of authentication were contained on the smart card,
' then Chilkat would already have them (via the FindCert function) and the certs in the chain will be automatically used
' as needed when signing occurs.

' If you have CA certs located elsewhere, such as in .cer files, you can make them available to Chilkat in the following way:

Dim certVault As New ChilkatXmlCertVault
' Please review the methods available in the XML certificate vault class.  Different methods exist for adding certificates
' from various sources, such as PEM, PFX, or in-memory sources..
success = certVault.AddCertFile("someDir/caIntermediateCert.cer")
' ...
success = certVault.AddCertFile("someDir/caCert.cer")
' (Your code should check the return value to make sure it succeeded.)

success = cert.UseCertVault(certVault)
If (success = 0) Then
    Debug.Print cert.LastErrorText
    success = pkcs11.CloseSession()
    Exit Sub
End If

' --------------------------------------------------------------------------
' At this point, we have the cert (and certs in the chain of authentication) to be used for signing.
' The code for using the certificate in creating the digital signature, such as for a PDF, XML, etc., go here...

' --------------------------------------------------------------------------

' Revert to an unauthenticated session by calling Logout.
success = pkcs11.Logout()
If (success = 0) Then
    Debug.Print pkcs11.LastErrorText
    success = pkcs11.CloseSession()
    Exit Sub
End If

' When finished, close the session.
' It is important to close the session (memory leaks will occur if the session is not properly closed).
success = pkcs11.CloseSession()
If (success = 0) Then
    Debug.Print pkcs11.LastErrorText
    Exit Sub
End If

Debug.Print "Success."