Visual FoxPro

Load Certificate from Smart Card by Key Usage

See more Certificates Examples

You may have a smartcard or USB token that contains only 2 certificates, one for signing, and one for authentication, and you wish to load the certificate for signing. This example demonstrates how to load the 1st certificate found on a smartcard that matches the intended key usage. Visual FoxPro

LOCAL lnSuccess
LOCAL loCert

lnSuccess = 0

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

loCert = CreateObject('Chilkat.Cert')

*  If you know the smart card PIN, set it prior to loading from the smartcard/USB token.
loCert.SmartCardPin = "12345678"

*  To load a certificate matching an intended key usage, specify the type of usage as shown below.
*  
*  The possible key usage keywords are:
*  
*  digitalsignature
*  Use when the public key is used with a digital signature mechanism to support security services other than non-repudiation, certificate signing, or CRL signing. 
*  A digital signature is often used for entity authentication and data origin authentication with integrity.

*  nonrepudiation
*  When a digital certificate's key usage includes "nonrepudiation," it implies that the certificate and its associated private key can be used to 
*  create digital signatures that provide proof of the origin and integrity of the signed data, and the signer cannot later deny having signed the data.

*  Other less common usages:

*  certificatesigning
*  keyencipherment
*  dataencipherment
*  crlsigning
*  secureemail
*  serverauthentication
*  clientauthentication
*  codesigning
*  timestamping

lnSuccess = loCert.LoadFromSmartcard("keyusage=nonrepudiation")
IF (lnSuccess = 0) THEN
    ? loCert.LastErrorText
    ? "Certificate not loaded."
    RELEASE loCert
    CANCEL
ENDIF

? "Found: " + loCert.SubjectDN + " serial=" + loCert.SerialNumber

RELEASE loCert