(Excel) Create JWT using Smart Card

See more JSON Web Token (JWT) Examples

Demonstrates how to create a JWT using an RSA private key and certificate on a smart card. This is for JOSE headers with an "alg" of RS256, RS384, or RS512. When RSA is used, the private key signs (creates) the JWT, and the public key is for verification.

This example also demonstrates how to include time constraints:

• nbf: Not Before Time
• exp: Expiration Time
• iat: Issue At Time

Download Excel Class Modules Chilkat Excel Class Modules

' Demonstrates how to create a JWT using an RSA private key and certificate on a smart card.

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

Dim jwt As Chilkat.Jwt
Set jwt = Chilkat.NewJwt
Dim cert As Chilkat.Cert
Set cert = Chilkat.NewCert


success = cert.LoadFromSmartcard("")
If (success = False) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

' Build the JOSE header
Dim jose As Chilkat.JsonObject
Set jose = Chilkat.NewJsonObject
' Use RS256.  Pass the string "RS384" or "RS512" to use RSA with SHA-384 or SHA-512.
Dim success As Boolean
success = jose.UpdateString("alg","RS256")
success = jose.UpdateString("typ","JWT")
success = jose.UpdateString("x5c[0]",cert.GetEncoded())

' Now build the JWT claims (also known as the payload)
Dim claims As Chilkat.JsonObject
Set claims = Chilkat.NewJsonObject
success = claims.UpdateString("iss","http://example.org")
success = claims.UpdateString("sub","John")
success = claims.UpdateString("aud","http://example.com")

' Set the timestamp of when the JWT was created to now.

curDateTime = jwt.GenNumericDate(0)
success = claims.UpdateInt("iat",curDateTime)

' Set the "not process before" timestamp to now.
success = claims.UpdateInt("nbf",curDateTime)

' Set the timestamp defining an expiration time (end time) for the token
' to be now + 1 hour (3600 seconds)
success = claims.UpdateInt("exp",curDateTime + 3600)

' Produce the smallest possible JWT:
jwt.AutoCompact = True


Set privKey = cert.ExportPrivateKey()
If (cert.LastMethodSuccess = False) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

' Create the JWT token.  This is where the RSA signature is created.

token = jwt.CreateJwtPk(jose.Emit(),claims.Emit(),privKey)

Debug.Print token