Classic ASP
Validate JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples
Validates a JSON Web Signature (JWS) using HMAC SHA-256.
Chilkat Classic ASP Downloads

Classic ASP
<html>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<%
success = 0

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

' This example takes a JSON signature in compact serialization format,
' and uses a MAC key to validate and recover the protected header and payload.

set jws = Server.CreateObject("Chilkat.Jws")

' Set the HMAC key:
hmacKey = "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow"
signatureIndex = 0
success = jws.SetMacKey(signatureIndex,hmacKey,"base64url")

' Load the JWS.
jwsCompact = "eyJ0eXAiOiJKV1QiLA0KICJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJqb2UiLA0KICJleHAiOjEzMDA4MTkzODAsDQogImh0dHA6Ly9leGFtcGxlLmNvbS9pc19yb290Ijp0cnVlfQ.dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"
success = jws.LoadJws(jwsCompact)

' Validate the 1st (and only) signature at index 0..
v = jws.Validate(signatureIndex)
If (v < 0) Then
    ' Perhaps Chilkat was not unlocked or the trial expired..
    Response.Write "<pre>" & Server.HTMLEncode( "Method call failed for some other reason.") & "</pre>"
    Response.Write "<pre>" & Server.HTMLEncode( jws.LastErrorText) & "</pre>"
    Response.End
End If

If (v = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( "Invalid signature.  The MAC key was incorrect, the JWS was invalid, or both.") & "</pre>"
    Response.End
End If

' If we get here, the signature was validated..
Response.Write "<pre>" & Server.HTMLEncode( "Signature validated.") & "</pre>"

' Recover the original content:
Response.Write "<pre>" & Server.HTMLEncode( "Recovered content:") & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( jws.GetPayload("utf-8")) & "</pre>"

' Examine the protected header:

set joseHeader = Server.CreateObject("Chilkat.JsonObject")
success = jws.GetProtectedH(signatureIndex,joseHeader)
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( jws.LastErrorText) & "</pre>"
    Response.End
End If

joseHeader.EmitCompact = 0

Response.Write "<pre>" & Server.HTMLEncode( "Protected (JOSE) header:") & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( joseHeader.Emit()) & "</pre>"

' Output:

' 	Signature validated.
' 	Recovered content:
' 	{"iss":"joe",
' 	 "exp":1300819380,
' 	 "http://example.com/is_root":true}
' 	Protected (JOSE) header:
' 	{ 
' 	  "typ": "JWT",
' 	  "alg": "HS256"
' 	}

%>
</body>
</html>