Lua Requires Chilkat v10.1.2+

RSA Sign String using Private Key of Certificate Type A3 (smart card / token)

See more RSA Examples

Demonstrates RSA signing a string using the private key of a certificate type A3 (smart card, token).

Note: This is a Windows-only example.

Lua

local chilkat = require("chilkat")

-- First get the A3 certificate that was installed on the Windows system.
local certStore = chilkat.CertStore.new()

local thumbprint = "12c1dd8015f3f03f7b1fa619dc24e2493ca8b4b2"

-- This is specific to Windows because it is opening the Windows Current-User certificate store.
local bReadOnly = true
local success = certStore:open_current_user_store(bReadOnly)
if not success then
    print(certStore.last_error_text)
    return
end

-- Find the certificate with the desired thumbprint
-- (There are many ways to locate a certificate.  This example chooses to find by thumbprint.)
local json = chilkat.JsonObject.new()
json:update_string("thumbprint", thumbprint)

local cert = chilkat.Cert.new()
success = certStore:find_cert(json, cert)
if not success then
    print("Failed to find the certificate.")
    return
end

print("Found: " .. cert.subject_cn)

local rsa = chilkat.Rsa.new()

-- Provide the cert's private key
local bUsePrivateKey = true
success = rsa:set_x509_cert(cert, bUsePrivateKey)
if not success then
    print(rsa.last_error_text)
    return
end

-- Return the RSA signature in base64 encoded form.
rsa.encoding_mode = "base64"

-- Sign the utf-8 byte representation of the string.
rsa.charset = "utf-8"

-- You can also choose other hash algorithms, such as SHA-1.
local sigBase64 = rsa:sign_string_enc("text to sign", "SHA-256")
if not rsa.last_method_success then
    print(rsa.last_error_text)
    return
end

print("Base64 signature: " .. sigBase64)