Classic ASP
JWE with Binary Data

See more JSON Web Encryption (JWE) Examples
Demonstrates how to create a JWE that contains a binary payload (such as a JPG image).
Note: This example requires Chilkat v9.5.0.66 or greater.
Chilkat Classic ASP Downloads

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

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

' Note: This example requires Chilkat v9.5.0.66 or greater.

' Load a JPG file that will be the JWE payload.
set jpgBytes = Server.CreateObject("Chilkat.BinData")
success = jpgBytes.LoadFile("qa_data/jpg/starfish.jpg")
' Make sure your app checks the success/failure of the call to LoadFile..
Response.Write "<pre>" & Server.HTMLEncode( "Original JPG size = " & jpgBytes.NumBytes) & "</pre>"

set jwe = Server.CreateObject("Chilkat.Jwe")

set jweProtHdr = Server.CreateObject("Chilkat.JsonObject")
success = jweProtHdr.AppendString("alg","A128KW")
success = jweProtHdr.AppendString("enc","A128CBC-HS256")
success = jwe.SetProtectedHeader(jweProtHdr)

aesWrappingKey = "GawgguFyGrWKav7AX4VKUg"
success = jwe.SetWrappingKey(0,aesWrappingKey,"base64url")

' Encrypt and return the JWE in sbJwe:
set sbJwe = Server.CreateObject("Chilkat.StringBuilder")
success = jwe.EncryptBd(jpgBytes,sbJwe)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( jwe.LastErrorText) & "</pre>"
    Response.End
End If

' Show the JWE:
Response.Write "<pre>" & Server.HTMLEncode( sbJwe.GetAsString()) & "</pre>"
Response.Write "<pre>" & Server.HTMLEncode( "size of JWE: " & sbJwe.Length) & "</pre>"

' ---------------------------------------------------------
' Decrypt to get the original JPG file..

set jwe2 = Server.CreateObject("Chilkat.Jwe")
success = jwe2.LoadJweSb(sbJwe)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( jwe2.LastErrorText) & "</pre>"
    Response.End
End If

' Set the AES wrap key.
success = jwe2.SetWrappingKey(0,aesWrappingKey,"base64url")

' Decrypt.
set jpgOriginal = Server.CreateObject("Chilkat.BinData")
success = jwe2.DecryptBd(0,jpgOriginal)
If (success <> 1) Then
    Response.Write "<pre>" & Server.HTMLEncode( jwe2.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Decrypted JPG size = " & jpgOriginal.NumBytes) & "</pre>"

' Save the decrypted JPG to a file.
success = jpgOriginal.WriteFile("qa_output/jwe_decrypted_starfish.jpg")

Response.Write "<pre>" & Server.HTMLEncode( "success = " & success) & "</pre>"

' The output of this program, when tested, was:
' Original JPG size = 6229
' eyJhbGciOiJBMTI4S1ciLCJlbmMiOiJBMTI4Q0JDLUhTMjU2In0.9YFz_wteV ... 7Et3hKhpxnKEXw
' size of JWE: 8473
' Decrypted JPG size = 6229
' success = True

%>
</body>
</html>