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PKCS11 Find Certificate with Key Usage on Smart Card or USB Token

See more PKCS11 Examples

Demonstrates how to find and return the 1st certificate on a smart card or USB token with a desired intended key usage.

Note: This example requires Chilkat v9.5.0.91 or later.

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Dim success As Boolean
success = False

// 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 Chilkat.Pkcs11

pkcs11.SharedLibPath = "aetpkss1.dll"

success = pkcs11.Initialize()
If (success = False) Then
    System.DebugLog(pkcs11.LastErrorText)
    Return
End If

// Pass -1 for the slotID to open a session on the first non-empty slot.
Dim slotID As Int32
slotID = -1

// Open a session.
Dim readWrite As Boolean
readWrite = True
success = pkcs11.OpenSession(slotID,readWrite)
If (success = False) Then
    System.DebugLog(pkcs11.LastErrorText)
    Return
End If

// Make it an authenticated session by calling Login.
// 
// If we don't authenticate, then we won't be able to see the private keys, and thus
// we won't know which certificates have an associated private key stored on the smart card.

// The smart card PIN is passed to the Login method.
// userType 1 indicates a "Normal User".
Dim userType As Int32
userType = 1
Dim pin As String
pin = "0000"
success = pkcs11.Login(userType,pin)
If (success = False) Then
    System.DebugLog(pkcs11.LastErrorText)
    success = pkcs11.CloseSession()
    Return
End If

// --------------------------------------------------------------------------

Dim cert As New Chilkat.Cert

// Find a certificate with an intended key usage.
// Possible key usages to find are:
// 
// DigitalSignature
// NonRepudiation
// KeyEncipherment
// DataEncipherment
// CertificateSigning
// CrlSigning
// 
// To find a cert having any one of several usages, pass a comma-separated list of usages:
success = pkcs11.FindCert("keyUsage","NonRepudiation,DigitalSignature",cert)
If (success = True) Then
    System.DebugLog("Cert with private key: " + cert.SubjectCN)
Else
    System.DebugLog("No certificates having the intended key usage were found.")
End If

// --------------------------------------------------------------------------

// Revert to an unauthenticated session by calling Logout.
success = pkcs11.Logout()
If (success = False) Then
    System.DebugLog(pkcs11.LastErrorText)
    success = pkcs11.CloseSession()
    Return
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 = False) Then
    System.DebugLog(pkcs11.LastErrorText)
    Return
End If

System.DebugLog("Success.")