Java函数如何提升物联网设备的安全性？

import com.google.cloud.functions.HttpFunction;
import com.google.cloud.functions.HttpRequest;
import com.google.cloud.functions.HttpResponse;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.security.GeneralSecurityException;
import java.security.spec.InvalidKeySpecException;
import java.util.Base64;
import java.util.logging.Logger;

public class DeviceAuth implements HttpFunction {
  private static final Logger logger = Logger.getLogger(DeviceAuth.class.getName());

  @Override
  public void service(HttpRequest request, HttpResponse response)
      throws IOException, GeneralSecurityException, InvalidKeySpecException {
    String encodedSignature = request.getFirstQueryParameter("sig").orElse("");
    String encodedMessage = request.getFirstQueryParameter("msg").orElse("");
    String encodedPublicKey = request.getFirstQueryParameter("key").orElse("");

    // Decode the signature, message, and public key
    byte[] signature = Base64.getDecoder().decode(encodedSignature);
    byte[] message = Base64.getDecoder().decode(encodedMessage);
    byte[] publicKey = Base64.getDecoder().decode(encodedPublicKey);

    // Validate the signature using the public key
    boolean validSignature = validateSignature(signature, message, publicKey);

    // Respond with the validation result
    if (validSignature) {
      response.setStatusCode(HttpFunction.HttpStatus.OK);
      response.getWriter().write("Success: Device is authenticated");
    } else {
      response.setStatusCode(HttpFunction.HttpStatus.UNAUTHORIZED);
      response.getWriter().write("Failure: Device is not authenticated");
    }
  }

  // Validate the signature using the public key
  private boolean validateSignature(byte[] signature, byte[] message, byte[] publicKey)
      throws GeneralSecurityException, InvalidKeySpecException {
    // Implement signature validation logic here...
    return true;  // Replace this with your actual signature validation logic
  }
}