(PHP Extension) Create JWK Set Containing Certificates

Demonstrates how to create a JWK Set containing N certificates.

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<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

// 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.
$cert1 = new CkCert();
$success = $cert1->LoadFromFile('qa_data/certs/brasil_cert.pem');
if ($success != true) {
    print $cert1->lastErrorText() . "\n";
    exit;
}

$cert2 = new CkCert();
$success = $cert2->LoadFromFile('qa_data/certs/testCert.cer');
if ($success != true) {
    print $cert2->lastErrorText() . "\n";
    exit;
}

// We'll need this crypt object re-encode the SHA1 thumbprint from hex to base64.
$crypt = new CkCrypt2();

$json = new CkJsonObject();

// Let's begin with the 1st cert:
$json->put_I(0);
$json->UpdateString('keys[i].kty','RSA');
$json->UpdateString('keys[i].use','sig');

$hexThumbprint = $cert1->sha1Thumbprint();
$base64Thumbprint = $crypt->reEncode($hexThumbprint,'hex','base64');
$json->UpdateString('keys[i].kid',$base64Thumbprint);
$json->UpdateString('keys[i].x5t',$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.
// pubKey is a CkPublicKey
$pubKey = $cert1->ExportPublicKey();
$pubKeyJwk = new CkJsonObject();
$pubKeyJwk->Load($pubKey->getJwk());

$json->UpdateString('keys[i].n',$pubKeyJwk->stringOf('n'));
$json->UpdateString('keys[i].e',$pubKeyJwk->stringOf('e'));

// Now add the entire X.509 certificate 
$json->UpdateString('keys[i].x5c[0]',$cert1->getEncoded());

// Now do the same for cert2..
$json->put_I(1);

$json->UpdateString('keys[i].kty','RSA');
$json->UpdateString('keys[i].use','sig');

$hexThumbprint = $cert2->sha1Thumbprint();
$base64Thumbprint = $crypt->reEncode($hexThumbprint,'hex','base64');
$json->UpdateString('keys[i].kid',$base64Thumbprint);
$json->UpdateString('keys[i].x5t',$base64Thumbprint);

// pubKey is a CkPublicKey
$pubKey = $cert2->ExportPublicKey();
$pubKeyJwk->Load($pubKey->getJwk());

$json->UpdateString('keys[i].n',$pubKeyJwk->stringOf('n'));
$json->UpdateString('keys[i].e',$pubKeyJwk->stringOf('e'));

// Now add the entire X.509 certificate 
$json->UpdateString('keys[i].x5c[0]',$cert2->getEncoded());

// Emit the JSON..
$json->put_EmitCompact(false);
print $json->emit() . "\n";

?>