B4X

Create JWT using a Brainpool EC Key

See more JSON Web Token (JWT) Examples

Demonstrates how to create a JWT using an EC private key. This is for JOSE headers having an "alg" member with any of the following values:

• BP160R1
• BP192R1
• BP224R1
• BP256R1
• BP320R1
• BP384R1
• BP512R1

This example also demonstrates how to include time constraints:

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

B4X

Dim success As Boolean = False

'  Demonstrates how to create a JWT using a brainpool EC private key.

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

Dim privKey As ChilkatPrivateKey
privKey.Initialize("privKey")

'  Load a brainpool EC key.
success = privKey.LoadPemFile("c:/qa_data/pem/ec_brainpool_privKey.pem")
If success <> True Then
    Log(privKey.LastErrorText)
    Return
End If


'  You can examine the curve name of the key you just loaded by getting the private in XML format:
'  <ECCKeyValue curve="CURVE_NAME">...</ECCKeyValue>
Log(privKey.GetXml)

Dim jwt As ChilkatJwt
jwt.Initialize

'  Build the JOSE header
Dim jose As ChilkatJsonObject
jose.Initialize
'  Use the brainpool curve name matching the private key you just loaded.
'  Use "BP256R1", or "BP384R1", etc.   
success = jose.AppendString("alg", "BP256R1")
success = jose.AppendString("typ", "JWT")

'  Now build the JWT claims (also known as the payload)
Dim claims As ChilkatJsonObject
claims.Initialize
success = claims.AppendString("iss", "http://example.org")
success = claims.AppendString("sub", "John")
success = claims.AppendString("aud", "http://example.com")

'  Set the timestamp of when the JWT was created to now.
Dim curDateTime As Int = jwt.GenNumericDate(0)
success = claims.AddIntAt(-1, "iat", curDateTime)

'  Set the "not process before" timestamp to now.
success = claims.AddIntAt(-1, "nbf", curDateTime)

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

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

'  Create the JWT token.  This is where the ECC signature is created.
Dim token As String = jwt.CreateJwtPk(jose.Emit, claims.Emit, privKey)

Log(token)