[Solved] – PROTON_SSL=1

This is a follow up to my recent post https://www.eknori.de/2018-12-28/problem-using-proton-with-proton_ssl1-enabled/

Due to my misunderstanding and also a lack in documentation, I was not able to get PROTON with PROTON_SSL=1 and PROTON_AUTHENTICATION=client_certs running.

But thanks to our great community and a little help from Jan Krejc√°rek (SUTOL), I was finally able to solve the puzzle.

I must admit that I am not an expert in this field. So please bare with me if things are obvious for you. They are (not yet) for me.

My understanding of using TLS/SSL with PROTON was that I could use my existing Let’s Encrypt certificate to communicate via HTTPS instead of HTTP with my server URL.

But this is not the case. TLS/SSL encryption only enables a secured communication between the domino.db module and the PROTON addin sitting on the Domino server.

Here is an image.

The second thing that I got wrong was the fact that the existing certificate and it’s CA would be enough to enable the secured communication. In my first test, I had set PROTON_AUTHENTICATION=anonymous.

So why bother with client certificates if they are not needed at this point?

I followed Jan’s advice to try with a new generated self-signed certificate. The AppDevPack contains shell scripts to create some sample certs and also lets you create a keyring file that can be used with PROTON.

I have modified the make_keyring.sh file a bit because it complained about missing environment variables.

# added UKR, 12/2018
export NOTESDATA=/local/notesdata
export NOTESBIN=/opt/ibm/domino/notes/10000000/linux

I then created the certs and keyring and copied them to the proper location.

The original source code has used

// proton config
const serverConfig = {
    "hostName": "serv02.fritz.box",
    "connection": {
        "port": 3002

to define the serverConfig. This must be enhanced, if you are going the secure way.

I created a new module using Jan’s code

const fs = require('fs');
const path = require('path');

 * Internal functions that reads a content of a file to a buffer.
 * @param {string} fileName 
const readFile = fileName => {
        return fs.readFileSync(path.resolve(fileName));

 * (c) Jan Krejc√°rek
 * Creates an object in a structure required for the DominoDB module
 * to initialize o connection to the Domino server.
 * @param {string} serverHostName Host name of the Domino server
 * @param {string} port TCP port number where a Proton task listens for connection requests
 * @param {string} rootCertificatePath Path to the certificate used to establish a TLS connection
 * @param {string} clientCertificatePath Path to the application certificate used to authenticate the application
 * @param {string} clienKeyPath Path to the private key of the application
const config = (serverHostName, port, rootCertificatePath, clientCertificatePath, clienKeyPath) => {
    const rootCertificate = readFile(rootCertificatePath);
    const clientCertificate = readFile(clientCertificatePath);
    const clientKey = readFile(clienKeyPath);
    const serverConfig = {
            hostName: serverHostName,
            connection: {
                    port: port,
                    secure: true
            credentials: {

    return serverConfig;

module.exports = config;

All parts in the credentials section are mandatory. Even if you use PROTON_AUTHENTICATION=anonymous with PROTON_SSL=1, you must have certificates and keys for the client as well.

And we can now use this module in app.js

const protonConfig = require('./protonConfigSSL.js');
const serverConfig = protonConfig("serv02.fritz.box", "3002", "./certs/proton-self/ca.crt", "./certs/proton-self/app1.crt", "./certs/proton-self/app1.key");

My PROTON configuration is

[029971:000009-00007F78D8293700] PROTON_AUTHENTICATION=client_cert
[029971:000009-00007F78D8293700] PROTON_KEYFILE=proton-self.kyr
[029971:000009-00007F78D8293700] PROTON_LISTEN_ADDRESS=serv02.fritz.box
[029971:000009-00007F78D8293700] PROTON_LISTEN_PORT=3002
[029971:000009-00007F78D8293700] PROTON_SSL=1
[029971:000009-00007F78D8293700] PROTON_TRACE_REQUEST=0
[029971:000009-00007F78D8293700] PROTON_TRACE_SESSION=0

And after restarting PROTON ( restart task proton ) and starting my application ( npm start ), I was able to open hp.nsf in the browser.

I also found an interesting article by Sven Hasselbach about how to protect PROTON keys.

I hope that this will help others starting with this stuff to save some time.

Recommended reading:

Heiko Voigt: DominoDB and a big NO-NO !

Sven Hasselbach ( response to Heiko’s post ): DominoDB and a big NO-NO?