Validate a JWS Signature

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.Validate, which validates exactly one signature, identified by a zero-based index, using the key configured at that same index.

Dim success As Boolean
success = False

Dim jws As New Chilkat.Jws

//  Load the JWS compact serialization.
Dim jwsCompact As String
jwsCompact = "eyJhbGciOiJIUzI1NiJ9.VGhpcyBpcyB0aGUgY29udGVudCB0byBzaWduLg.<signature>"
success = jws.LoadJws(jwsCompact)
If (success = False) Then
    System.DebugLog(jws.LastErrorText)
    Return
End If

//  Provide the key for signature 0 (here an HMAC key).
Dim base64Key As String
base64Key = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU="
success = jws.SetMacKey(0,base64Key,"base64")
If (success = False) Then
    System.DebugLog(jws.LastErrorText)
    Return
End If

//  Validate the signature identified by the zero-based index, using the key configured at that index.
//  Validate returns 1 when the signature or MAC is cryptographically valid, 0 when it is not, or a
//  negative value on error.
Dim v As Int32
v = jws.Validate(0)
If (v < 0) Then
    System.DebugLog(jws.LastErrorText)
    Return
End If

If (v <> 1) Then
    System.DebugLog("The signature is not valid.")
    Return
End If

System.DebugLog("The signature is valid.")