moonfire-nvr/guide/secure.md

Securing Moonfire NVR and exposing it to the Internet

The problem

After you've completed the Downloading, installing, and configuring NVR guide, you should have a running system you can use from within your home, but one that is insecure in a couple ways:

1. It doesn't use https to encrypt connections & authenticate itself to you.
2. It doesn't require you to sign in (with your chosen username and password) to authenticate yourself to it.

You'll want to change these points if you expose Moonfire NVR's web interface to the Internet. Security-minded folks would say you shouldn't even allow unauthenticated sessions within your local network.

Besides security, the nature of home Internet setups presents challenges in exposing Moonfire NVR to the Internet:

1. you likely have a single IPv4 address that all your devices share via NAT. (Your ISP may also provide a set of IPv6 addresses; even if they do, you likely don't have IPv6 available everywhere you want to connect from.) You'll need to set up "port forwarding" on your home router, and there are many routers with different interfaces for doing so.
2. that IPv4 address is likely dynamic, so you'll need to configure "dynamic DNS" to get a consistent URL to access Moonfire NVR. Most people do this through their router's interface as well.
3. you may want to share your single IP address's http and https ports with other web interfaces, such as a network-attached storage device. This requires setting up a proxy and configuring it with each destination.
4. unlike some commercial providers, Moonfire NVR doesn't have any central organization to provide a central high-bandwidth, Internet-accessible proxying service.

This guide is therefore more abstract than the previous installation steps, and may even make assumptions that aren't true for your setup. Improvements are welcome, but it's not possible to make a single terse, concrete guide that will work for everyone. If you're not a networking expert, you may need to consult your home router's manual and other external guides or forums.

VPN or port forwarding?

This guide describes how to set up Moonfire NVR with port forwarding.

Any security camera forums such as ipcamtalk will recommend that you use a VPN to connect to your NVR rather than port forwarding. The backstory is that most NVRs are untrustworthy. They have low-budget, closed-source software written by companies which at best aren't security-conscious and at worst allow the Chinese government to use deliberate backdoors.

A VPN's advantage is that it doesn't allow any incoming traffic to reach the NVR until after authentication, so it's far more secure when the NVR can't be trusted to perform proper authentication itself.

Port forwarding's advantage is that, once installed on the server, it's far more convenient to use. There's no VPN client necessary, just a web browser.

I believe Moonfire NVR authenticates properly. It's also open-source, so it's practical to verify this yourself given sufficient time and expertise.

If you'd prefer to use a VPN, the ipcamtalk Cliff Notes suggest reading Network Security Primer and/or VPN Primer for Noobs.

Overview

1. Install a webserver
2. Configure a static internal IP
3. Set up port forwarding
4. Configure a public DNS name
5. Install a TLS certificate
6. Reconfigure Moonfire NVR
7. Configure the webserver
8. Verify it works

1. Install a webserver

Moonfire NVR's builtin webserver doesn't yet support https (see issue #27), so you'll need to proxy through a webserver that does. If Moonfire NVR will be sharing an https port with anything else, you'll need to set up the webserver to proxy to all of these interfaces as well.

I use nginx as the proxy server. Some folks may prefer Apache httpd or some other webserver. Anything will work. I include snippets of a nginx config below, so stick with that if you're not comfortable adapting it to some other server.

I run the proxying webserver on the same machine as Moonfire NVR itself. You might want to do something else, but this is the simplest setup that means you only need to configure one machine with a static internal IP address.

digitalocean has a nice How to install Nginx on Ubuntu 18.04 guide.

2. Configure a static internal IP

When you configure port forwarding on your router, you'll most likely have to specify the destination as an internal IP address. You could look up the current IP address of the webserver machine, but it might change, and your setup will break if it does.

The easiest way to ensure your setup keeps working is to use the "static DHCP lease" option on your home router to give your webserver machine the same address every time it asks for a new lease.

(Alternatively, you can configure your webserver to use a static IP address instead of asking for a DHCP lease. Ensure the address you choose is outside the range assigned by the DHCP server, so that there are no conflicts.)

Reboot the webserver machine now and ensure it uses the IP address you choose on startup, so you don't have a confusing experience after your next power failure.

3. Set up port forwarding

In your router's setup, go to the "Port Forwarding" section and tell it to forward TCP requests on the http port (80) and the https port (443) to your webserver. The https port is necessary for secure access, and the http port is necessary for the Let's Encrypt http-01 challenge during the setup process.

Now if you go to your external IP address in a web browser, you should reach your webserver.

4. Configure a public DNS name

Also in your router's setup, look for "Dynamic DNS" or "DDNS". Configure it to update some DNS name with your home's external IP address. You should then be able to go to this address in a web browser and reach your webserver again.

(It's possible to instead set up a dynamic DNS client on the Moonfire NVR machine instead. See this Ubuntu guide. One disadvantage is that it may be slower to recognize IP address changes, so there may be a longer period in which the address is incorrect.)

5. Install a TLS certificate

I recommend using the Let's Encrypt Certificate Authority to obtain a TLS certificate that will be automatically trusted by your browser. See How to secure Nginx with Let's Encrypt on Ubuntu 18.04.

6. Reconfigure Moonfire NVR

If you follow the recommended Docker setup, your /usr/local/bin/nvr script will contain this line:

                --allow-unauthenticated-permissions='view_video: true'

Replace it with the following:

                --trust-forward-hdrs

This change has two effects:

• No --allow-unauthenticated-permissions means that web users must authenticate.
• --trust-forward-hdrs means that Moonfire NVR will look for X-Real-IP and X-Forwarded-Proto headers as added by the webserver configuration in the next section.

If the webserver is running on the same machine as Moonfire NVR, you might also change --publish=8080:8080 to --publish=127.0.0.1:8080:8080, which prevents other machines on the network from impersonating the proxy, effectively allowing them to lie about the client's IP and protocol.

To make this take effect, you'll need to stop the running Docker container, delete it, and create/run a new one:

$ nvr stop
$ nvr rm
$ nvr run

7. Configure the webserver

Since step 5, you should have a https-capable webserver set up on your desired DNS name. Now finalize its configuration:

• redirect all http traffic to https
• proxy https traffic to Moonfire NVR
• when proxying, add a X-Real-IP header with the original IP address
• when proxying, add a X-Forwarded-Proto header with the original protocol (which should be https if you've configured everything correctly).

The author's system does this via the following /etc/nginx/sites-available/nvr.home.slamb.org file:

upstream moonfire {
    server 127.0.0.1:8080;
}

map $http_upgrade $connection_upgrade {
    default Upgrade;
    ''      close;
}

server {
    root /var/www/html;
    index index.html index.htm index.nginx-debian.html;

    server_name nvr.home.slamb.org;

    location / {
        proxy_pass http://moonfire;
        # try_files $uri $uri/ =404;
    }

    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $connection_upgrade;

    proxy_set_header X-Forwarded-Proto $scheme;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header Host $http_host;
    proxy_redirect http:// $scheme://;

    listen [::]:443 ssl ipv6only=on; # managed by Certbot
    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/nvr.home.slamb.org/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/nvr.home.slamb.org/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

server {
    listen 80;
    listen [::]:80;

    return 301 https://nvr.home.slamb.org$request_uri;

    server_name nvr.home.slamb.org nvr;
}

Check your configuration for syntax errors and reload it:

$ sudo nginx -t
$ sudo systemctl reload nginx

Verify it works

Go to http://your.domain.here/api/request and verify the following:

• the browser redirects from http to https
• the address shown here matches your web browser's public IP address. (Compare to https://whatsmyip.com/.)
• the page says secure: true indicating you are using https.

Then go to https://your.domain.here/ and you should see the web interface, including a login form.

Login with the credentials you added through moonfire-nvr config in the previous guide. You should see your username and "logout" in the upper-right corner of the web interface.

Also try the live streaming feature, which requires WebSockets. The nginx configuration above includes sections derived from nginx's NGINX as a WebSocket Proxy doc.

If it doesn't work as expected, re-read this guide, then open an issue on github for help.