code: package duo.labs.webauthn.models;
  
  import android.util.Base64;
  
  import java.io.ByteArrayOutputStream;
  import java.util.Arrays;
  
  import co.nstant.in.cbor.CborBuilder;
  import co.nstant.in.cbor.CborEncoder;
  import co.nstant.in.cbor.CborException;
  import duo.labs.webauthn.exceptions.VirgilException;
  
  public class NoneAttestationObject extends AttestationObject {
      /**
       * Construct a new self-attestation attObj in packed format.
       *
       * @param authData The authenticator data.
       */
      public NoneAttestationObject(byte[] authData) {
          this.authData = authData;
      }
  
      /**
       * Encode this self-attestation attObj as the CBOR required by the WebAuthn spec
       * https://www.w3.org/TR/webauthn/#sctn-attestation
       * https://www.w3.org/TR/webauthn/#none-attestation
       *
       * @return CBOR encoding of the attestation object as a byte array
       * @throws VirgilException
       */
      @Override
      public byte[] asCBOR() throws VirgilException {
          ByteArrayOutputStream baos = new ByteArrayOutputStream();
          try {
              new CborEncoder(baos).encode(new CborBuilder()
                      .addMap()
                      .put("authData", this.authData)
                      .put("fmt", "none")
                      .putMap("attStmt")
                      .end()
                      .end()
                      .build()
              );
          } catch (CborException e) {
              throw new VirgilException("couldn't serialize to cbor", e);
          }
          return baos.toByteArray();
      }
  }
  