(Visual FoxPro) JWE using ECDH-ES, BP-256, A256GCM

See more JSON Web Encryption (JWE) Examples

Create a JWE with the following header:

	{
	  "alg": "ECDH-ES",
	  "enc": "A256GCM",
	  "exp": 1621957030,
	  "cty": "NJWT",
	  "epk": {
	    "kty": "EC",
	    "x": "QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w"
	    "y": "AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu"
	    "crv": "BP-256"
	  }
	}

Note: This example requires Chilkat v9.5.0.87 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL lnSuccess
LOCAL loJson
LOCAL loPubkey
LOCAL loJwt
LOCAL loJweProtHdr
LOCAL loJwe
LOCAL lcPlainText
LOCAL lcStrJwe

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

* Load our brainpool BP-256 public key.

* 	{
* 	  "use": "enc",
* 	  "kid": "puk_idp_enc",
* 	  "kty": "EC",
* 	  "crv": "BP-256",
* 	  "x": "QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w",
* 	  "y": "AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu"
* 	}

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJson = CreateObject('Chilkat.JsonObject')
loJson.UpdateString("use","enc")
loJson.UpdateString("kid","puk_idp_enc")
loJson.UpdateString("kty","EC")
loJson.UpdateString("crv","BP-256")
loJson.UpdateString("x","QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w")
loJson.UpdateString("y","AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu")

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.PublicKey')
loPubkey = CreateObject('Chilkat.PublicKey')

lnSuccess = loPubkey.LoadFromString(loJson.Emit())
IF (lnSuccess = 0) THEN
    ? loPubkey.LastErrorText
    RELEASE loJson
    RELEASE loPubkey
    CANCEL
ENDIF

* Build our protected header:

* 	{
* 	  "alg": "ECDH-ES",
* 	  "enc": "A256GCM",
* 	  "exp": 1621957030,
* 	  "cty": "NJWT",
* 	  "epk": {
* 	    "kty": "EC",
* 	    "x": "QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w"
* 	    "y": "AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu"
* 	    "crv": "BP-256"
* 	  }
* 	}

* Use jwt only for getting the current date/time + 3600 seconds.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Jwt')
loJwt = CreateObject('Chilkat.Jwt')

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.JsonObject')
loJweProtHdr = CreateObject('Chilkat.JsonObject')
loJweProtHdr.UpdateString("alg","ECDH-ES")
loJweProtHdr.UpdateString("enc","A256GCM")
loJweProtHdr.UpdateInt("exp",loJwt.GenNumericDate(3600))
loJweProtHdr.UpdateString("cty","NJWT")
loJweProtHdr.UpdateString("epk.kty","EC")
loJweProtHdr.UpdateString("epk.x","QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w")
loJweProtHdr.UpdateString("epk.y","AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu")
loJweProtHdr.UpdateString("epk.crv","BP-256")

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Jwe')
loJwe = CreateObject('Chilkat.Jwe')
loJwe.SetProtectedHeader(loJweProtHdr)
loJwe.SetPublicKey(0,loPubkey)

lcPlainText = "This is the text to be encrypted."
lcStrJwe = loJwe.Encrypt(lcPlainText,"utf-8")
IF (loJwe.LastMethodSuccess <> 1) THEN
    ? loJwe.LastErrorText
    RELEASE loJson
    RELEASE loPubkey
    RELEASE loJwt
    RELEASE loJweProtHdr
    RELEASE loJwe
    CANCEL
ENDIF

? lcStrJwe

? "Success."

RELEASE loJson
RELEASE loPubkey
RELEASE loJwt
RELEASE loJweProtHdr
RELEASE loJwe