(Excel) Create JWK Set Containing Certificates

Demonstrates how to create a JWK Set containing N certificates.

Download Excel Class Modules Chilkat Excel Class Modules

' This example creates the following JWK Set from two certificates:

' {
'   "keys": [
'     {
'       "kty": "RSA",
'       "use": "sig",
'       "kid": "BB8CeFVqyaGrGNuehJIiL4dfjzw",
'       "x5t": "BB8CeFVqyaGrGNuehJIiL4dfjzw",
'       "n": "nYf1jpn7cFdQ...9Iw",
'       "e": "AQAB",
'       "x5c": [
'         "MIIDBTCCAe2...Z+NTZo"
'       ]
'     },
'     {
'       "kty": "RSA",
'       "use": "sig",
'       "kid": "M6pX7RHoraLsprfJeRCjSxuURhc",
'       "x5t": "M6pX7RHoraLsprfJeRCjSxuURhc",
'       "n": "xHScZMPo8F...EO4QQ",
'       "e": "AQAB",
'       "x5c": [
'         "MIIC8TCCAdmgA...Vt5432GA=="
'       ]
'     }
'   ]
' }

' First get two certificates from files.
Dim cert1 As Chilkat.Cert
Set cert1 = Chilkat.NewCert

success = cert1.LoadFromFile("qa_data/certs/brasil_cert.pem")
If (success <> True) Then
    Debug.Print cert1.LastErrorText
    Exit Sub
End If

Dim cert2 As Chilkat.Cert
Set cert2 = Chilkat.NewCert
success = cert2.LoadFromFile("qa_data/certs/testCert.cer")
If (success <> True) Then
    Debug.Print cert2.LastErrorText
    Exit Sub
End If

' We'll need this crypt object re-encode the SHA1 thumbprint from hex to base64.
Dim crypt As Chilkat.Crypt2
Set crypt = Chilkat.NewCrypt2

Dim json As Chilkat.JsonObject
Set json = Chilkat.NewJsonObject

' Let's begin with the 1st cert:
json.I = 0
success = json.UpdateString("keys[i].kty","RSA")
success = json.UpdateString("keys[i].use","sig")


hexThumbprint = cert1.Sha1Thumbprint

base64Thumbprint = crypt.ReEncode(hexThumbprint,"hex","base64")
success = json.UpdateString("keys[i].kid",base64Thumbprint)
success = json.UpdateString("keys[i].x5t",base64Thumbprint)

' (We're assuming these are RSA certificates)
' To get the modulus (n) and exponent (e), we need to get the cert's public key and then get its JWK.

Set pubKey = cert1.ExportPublicKey()
Dim pubKeyJwk As Chilkat.JsonObject
Set pubKeyJwk = Chilkat.NewJsonObject
success = pubKeyJwk.Load(pubKey.GetJwk())

success = json.UpdateString("keys[i].n",pubKeyJwk.StringOf("n"))
success = json.UpdateString("keys[i].e",pubKeyJwk.StringOf("e"))

' Now add the entire X.509 certificate 
success = json.UpdateString("keys[i].x5c[0]",cert1.GetEncoded())

' Now do the same for cert2..
json.I = 1

success = json.UpdateString("keys[i].kty","RSA")
success = json.UpdateString("keys[i].use","sig")

hexThumbprint = cert2.Sha1Thumbprint
base64Thumbprint = crypt.ReEncode(hexThumbprint,"hex","base64")
success = json.UpdateString("keys[i].kid",base64Thumbprint)
success = json.UpdateString("keys[i].x5t",base64Thumbprint)

Set pubKey = cert2.ExportPublicKey()
success = pubKeyJwk.Load(pubKey.GetJwk())

success = json.UpdateString("keys[i].n",pubKeyJwk.StringOf("n"))
success = json.UpdateString("keys[i].e",pubKeyJwk.StringOf("e"))

' Now add the entire X.509 certificate 
success = json.UpdateString("keys[i].x5c[0]",cert2.GetEncoded())

' Emit the JSON..
json.EmitCompact = False
Debug.Print json.Emit()