(PHP Extension) 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 PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

include("chilkat_9_5_0.php");

// 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"
// 	}

$json = new CkJsonObject();
$json->UpdateString('use','enc');
$json->UpdateString('kid','puk_idp_enc');
$json->UpdateString('kty','EC');
$json->UpdateString('crv','BP-256');
$json->UpdateString('x','QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w');
$json->UpdateString('y','AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu');

$pubkey = new CkPublicKey();

$success = $pubkey->LoadFromString($json->emit());
if ($success == false) {
    print $pubkey->lastErrorText() . "\n";
    exit;
}

// 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.
$jwt = new CkJwt();

$jweProtHdr = new CkJsonObject();
$jweProtHdr->UpdateString('alg','ECDH-ES');
$jweProtHdr->UpdateString('enc','A256GCM');
$jweProtHdr->UpdateInt('exp',$jwt->GenNumericDate(3600));
$jweProtHdr->UpdateString('cty','NJWT');
$jweProtHdr->UpdateString('epk.kty','EC');
$jweProtHdr->UpdateString('epk.x','QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w');
$jweProtHdr->UpdateString('epk.y','AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu');
$jweProtHdr->UpdateString('epk.crv','BP-256');

$jwe = new CkJwe();
$jwe->SetProtectedHeader($jweProtHdr);
$jwe->SetPublicKey(0,$pubkey);

$plainText = 'This is the text to be encrypted.';
$strJwe = $jwe->encrypt($plainText,'utf-8');
if ($jwe->get_LastMethodSuccess() != true) {
    print $jwe->lastErrorText() . "\n";
    exit;
}

print $strJwe . "\n";

print 'Success.' . "\n";

?>