Lua

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. Lua

local chilkat = require("chilkat")

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

local cert = chilkat.Cert.new()

-- If you know the smart card PIN, set it prior to loading from the smartcard/USB token.
cert.smart_card_pin = "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

local success = cert:load_from_smartcard("keyusage=nonrepudiation")
if not success then
    print(cert.last_error_text)
    print("Certificate not loaded.")
    return
end

print("Found: " .. cert.subject_dn .. " serial=" .. cert.serial_number)