Using x509 Client Certificates with Azure IoT Protocol Gateway with Node

Instructions.md

Instructions for local debug

• Download and install the Azure Storage Emulator

• Start the emulator from the Start Menu

• Add 127.0.0.1 protocol-gateway.contoso.com to your windows hosts file: C:\Windows\System32\drivers\etc\hosts

• git clone https://github.com/Azure/azure-iot-protocol-gateway

• Right Click Visual Studio and select Run As Administrator

• Open the Protocol Gateway Solution

• Modify the VS Solution host\ProtocolGateway.Host.Console\appSettings.config.user file with your IoT Hub Connection String

• Run the Solution

• Create a directory for the Node project

• Copy the other files in this gist to the project directory

• run npm install

Open an Adminstrative Powershell Terminal

New-SelfSignedCertificate -certstorelocation cert:\localmachine\my -dnsname orin.windowsitpro.internal

Assign the thumbprint from the previous command to a variable

$thumbprint = {the return value of the previous command}

Create a password for the cert

$pwd = ConvertTo-SecureString -String "{secure_password}" -Force -AsPlainText

Export the certificate

Export-PfxCertificate -cert "cert:\localMachine\my\$thumbprint" -FilePath c:\temp\cert.pfx -Password $pwd

Open Bash in the Windows Subsystem for Linux and type the following commands

• cd /mnt/c/temp

• openssl pkcs12 -in cert.pfx -nocerts -out key.pem -nodes

• openssl pkcs12 -in cert.pfx -nokeys -out cert.pem

• openssl rsa -in key.pem -out server.key

• In Windows Explorer copy the cert files to the Node Project source directory

• Edit the main.js connectionString with your IoT Hub hostname and Url for the running protocol gateway(protocol-gateway.contoso.com).

• From a terminal in the Node project directory run node main.js

main.js

'use strict';
var fs = require('fs');
var Protocol = require('azure-iot-device-mqtt').Mqtt;
var Client = require('azure-iot-device').Client;
var Message = require('azure-iot-device').Message;

var connectionString = "HostName={iot-hub-hostname}.azure-devices.net;DeviceId=devicex509;GatewayHostName=ssl:{protocol-gateway-url}:8883;x509=true"

var certFile = './cert.pem';
var keyFile = './key.pem';
var passphrase = 'pass@word';

var client = Client.fromConnectionString(connectionString, Protocol);

var connectCallback = function (err) {

  if (err) {

    console.error('Could not connect: ' + err.message);

  } else {

    console.log('Client connected');

    client.on('message', function (msg) {

      console.log('Id: ' + msg.messageId + ' Body: ' + msg.data);
      client.complete(msg, printResultFor('completed'));

    });

    var sendInterval = setInterval(function () {

      var windSpeed = 10 + (Math.random() * 4); // range: [10, 14]
      var temperature = 20 + (Math.random() * 10); // range: [20, 30]
      var humidity = 60 + (Math.random() * 20); // range: [60, 80]
      var data = JSON.stringify({ deviceId: 'devicex509', windSpeed: windSpeed, temperature: temperature, humidity: humidity });
      var message = new Message(data);
      message.properties.add('temperatureAlert', (temperature > 28) ? 'true' : 'false');
      console.log('Sending message: ' + message.getData());
      client.sendEvent(message, printResultFor('send'));

    }, 2000);

    client.on('error', function (err) {

      console.error(err.message);

    });

    client.on('disconnect', function () {

      clearInterval(sendInterval);
      client.removeAllListeners();
      client.open(connectCallback);

    });

  }

};

var options = {

   cert : fs.readFileSync(certFile, 'utf-8').toString(),
   key : fs.readFileSync(keyFile, 'utf-8').toString(),
   passphrase: passphrase

 };

client.setOptions(options);
client.open(connectCallback);

function printResultFor(op) {

  return function printResult(err, res) {

    if (err) console.log(op + ' error: ' + err.toString());
    if (res) console.log(op + ' status: ' + res.constructor.name);

  };
}

package.json

{
  "name": "gm-cert-demo",
  "version": "1.0.0",
  "description": "",
  "main": "main.js",
  "dependencies": {
    "azure-iot-device": "^1.1.11",
    "azure-iot-device-amqp": "^1.1.11",
    "azure-iot-device-mqtt": "^1.1.11"
  },
  "devDependencies": {},
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "William Berry @williamberryiii",
  "license": "MIT"
}