title: Adding card to Apple Wallet
body: <pre><code> func addPaymentPassViewController(_ controller: PKAddPaymentPassViewController, generateRequestWithCertificateChain certificates: [Data], nonce: Data, nonceSignature: Data, completionHandler handler: @escaping (PKAddPaymentPassRequest) -&gt; Void) {
  </code></pre>
  <p>I am getting certificates [Data], from this method. How to sign this certificates with CA Authority and convert them to base64 string.</p>
  <p>How to download root CA to validate this chain</p>
  <p>Can anyone help me on this.</p>
  <p>Thank you</p>