Mistborn is your own virtual private cloud platform and WebUI that manages self hosted services, and secures them with firewall, Wireguard VPN w/ PiHole-DNSCrypt, and IP filtering. Optional SIEM+IDS. Supports 2FA, Nextcloud, Jitsi, Home Assistant, +
The term [Mistborn](http://www.brandonsanderson.com/the-mistborn-saga-the-original-trilogy) is inspired by a type of powerful Allomancer in Brandon Sanderson's Cosmere.
Mistborn started as a passion project for a husband and father protecting his family. Certain family members insisted on connecting their devices to free WiFi networks. We needed a way to secure all family devices with a solid VPN (Wireguard). Once we had that we wanted to control DNS to block ads to all devices and block malicious and pornographic websites across all family devices. Then we wanted chat, file-sharing, and webchat services that we could use for ourselves without entrusting our data to some big tech company. And then... home automation. I know I'll be adding services as I go so I made that easy to do.
Mistborn depends on these open source technologies:
These tools are not vital to Mistborn itself but are integrated to enhance security, ease, and features:
- [iptables](https://www.netfilter.org): The powerful Linux netfilter firewall tool
- [cockpit](https://cockpit-project.org): A Graphical User Interface for system management, including container management
- [Pi-hole](https://pi-hole.net): A DNS server for network-wide ad blocking, etc
- [DNScrypt](https://www.dnscrypt.org): prevents DNS spoofing via cryptographic signatures to verify that responses originate from the chosen DNS resolver and haven't been tampered
- [Traefik](https://docs.traefik.io): A modern, efficient reverse-proxy
- [Home Assistant](https://www.home-assistant.io): Open source home automation that puts local control and privacy first
- [Nextcloud](https://nextcloud.com): Nextcloud offers the industry-leading, on-premises content collaboration platform. It combines the convenience and ease of use of consumer-grade solutions like Dropbox and Google Drive with the security, privacy and control business needs.
- [BitWarden](https://bitwarden.com): Password manager. The easiest and safest way for individuals, teams, and business organizations to store, share, and sync sensitive data.
- [Syncthing](https://syncthing.net): Syncthing is a continuous file synchronization program. It synchronizes files between two or more computers in real time, safely protected from prying eyes.
- [OnlyOffice](https://www.onlyoffice.com): Cloud office suite. ONLYOFFICE provides you with the most secure way to create, edit and collaborate on business documents online.
- [Rocket.Chat](https://rocket.chat): Free, Open Source, Enterprise Team Chat.
- [Jellyfin](https://jellyfin.org): The Free Media Software System.
- [Tor](https://www.torproject.org): The Onion Router. One tool in the arsenal of online security and privacy.
Pihole provides a way to block outgoing DNS requests for given lists of blocked domains. Coppercloud provides a way to block outgoing network calls of all types to given lists of IP addresses (IPv4 only for now). This is especially useful for blocking outgoing telemetry (data and state sharing) to owners of software running on all of your devices.
This example shows Coppercloud blocking a list of Microsoft IP addresses on a network with Windows 10 clients.
*Netflix blocking my connections that it sees coming from a DigitalOcean droplet*
In Mistborn, Gateways are upstream from the VPN server so connections to third-party services (e.g. Netflix, Hulu, etc.) will appear to be coming from the public IP address of the Gateway. I setup a Gateway at home, then all VPN profiles created with this Gateway will apear to be coming from my house and are not blocked. No port-forwarding required (assuming Mistborn is publicly accessible).
Mistborn is regularly tested on Ubuntu 18.04 LTS (DigitalOcean droplet with 2 GB RAM). It has also been successfully used on Debian Buster and Raspbian Buster systems (though not regularly tested). Additionally tested on Ubuntu 20.04 LTS.
When Mistborn-base starts up it will create volumes, initialize the PostgreSQL database, start pihole, run Django migrations and then check to see if a Mistborn superuser named `admin` exists yet. If not, it will create the superuser `admin` along with an accompanying default Wireguard configuration file and start the Wireguard service. You can watch all of this happen with:
[Install wireguard](https://www.wireguard.com/install/) on your computer. If you get a `resolvconf: command not found` error when starting Wireguard then install openresolv: `sudo apt-get install -y openresolv`
Mistborn users can be added (non-privileged or superuser) and removed by superusers. Multiple Wireguard profiles can be created for each user. A non-privileged user can create profiles for themselves.
*Wireguard Management in Mistborn*
## Extra Services
Mistborn makes extra services available.
*Mistborn Extra Services Available*
## Mistborn Firewall Metrics
Mistborn functions as a network firewall and provides metrics on blocked probes from the internet.
Mistborn will generate the Wireguard configuration script for the Gateway. From a base Ubuntu/Debian/Raspbian operating system the following packages are recommended to be installed beforehand:
Once you're connected to Wireguard you should see .mistborn domains and the internet should work as expected. Be sure to use http (http://home.mistborn). Wireguard is the encrypted channel so there's usually no need to bother with TLS certs (WebRTC functionality and some mobile apps require TLS so it is available). Here are some things to check if you have issues:
Note the Mistborn naming convention for Wireguard interfaces on the server is wg<listeningport>. So if the particular Wireguard process is listening on UDP port 56392 then the interface will be named wg56392 and the config will be in `/etc/wireguard/wg56392.conf`
Instead of defaulting to a system DNS server, Docker will try to use a public DNS server (e.g. 8.8.8.8). If you're having issues pulling or building Docker containers with "failure to connect" errors, this is the likely problem. You can manually set the DNS server Docker should use with the `DOCKER_OPTS` field in `/etc/default/docker`. Example:
These are some notes regarding the technical design and implementations of Mistborn. Feel free to contact me for additional details.
## Attack Surface
- **Wireguard**: Wireguard is the only way in to Mistborn. When new Wireguard profiles are generated they are attached to a random UDP port. Wireguard does not respond to unauthenticated traffic. External probes on the active Wireguard listening ports are not logged and do not appear on the Metrics page.
- **SSH**: If Mistborn is installed over SSH (most common) then an iptables rule is added allowing future SSH connections from the same source IP address. All other external SSH is blocked. Internal SSH (over the Wireguard tunnels) is allowed. Password authentication is disabled. The SSH key for the `mistborn` user is only accepted from internal source IP addresses. Fail2ban is also installed.
- **Traefik**: Iptables closes web ports (TCP 80 and 443) from external access and additonally all web interfaces are behind the Traefik reverse-proxy. All web requests (e.g. home.mistborn) must be resolved by Mistborn DNS (Pihole/dnsmasq) and originate from a Wireguard tunnel.
- **Docker**: When Docker exposes a port it creates a PREROUTING rule in the NAT table to catch eligible network requests. This means that even if your INPUT chain policy is DROP, your docker containers with exposed ports can receive and respond to traffic. Whenever Mistborn brings up a docker container with an exposed port it creates an iptables rule to block external traffic to that service.
## Firewall
- **IPtables**: Iptables rules and chains are manipulated directly. If UFW is present it is disabled. IPtables-persistent is used to save a simple set of secure default rules (most importantly setting the INPUT and FORWARD policies to DROP and allowing ESTABLISHED and RELATED traffic) that will be effective immediately upon system startup. Additional rules and chains are created by Docker on startup. Mistborn also creates some iptables chains during installation that are saved in the persistent rules. Mistborn iptables chains and rules are designed to work with Docker's with logic that is easy to follow. A power cycle will always result in a working state.
- **PostUp/PostDown**: Wireguard configuration files on Mistborn include PostUp and PostDown directives that set routes and iptables rules for each Wireguard client individually.
- **Wireguard**: There is a one-to-one mapping between each Wireguard client and server instance listening on Mistborn. By design Wireguard clients cannot talk directly to each other but can use shared services and resources on Mistborn (e.g. Syncthing, Nextcloud, Jitisi, etc.)
- **Metrics**: In addition to the iptables INPUT policy set to DROP, an iptables chain exists that logs the packet meta data before dropping it. Mistborn redirects packets that will be dropped to this chain instead. A summary of the data about these dropped packets (unsolicited network traffic) can be found on the Metrics page.
- **Coppercloud**: Coppercloud works by populating ipsets with the ipset module in iptables to DROP (blacklist) or ACCEPT (whitelist) a given set of IP addresses. Upon system startup a celery task will compile the IP addresses, create the ipsets, and iptables rules.
## Additonal Notes
- Interface names are not hardcoded anywhere in Mistborn. Two commands that are used in different circumstances to determine the default network interface and the interface that would route a public IP address are: `ip -o -4 route show to default` and `ip -o -4 route get 1.1.1.1`.
- The "Update" button will pull updated Docker images for mistborn, postgresql, redis, pihole, and dnscrypt. Those services will then be restarted.
- The generated TLS certificate has an RSA modulus of 4096 bits, is signed with SHA-256, and is good for 10 years. The nanny at Apple has decided to restrict the kinds of certificates iOS users may choose to manually trust and so you may have issues with TLS on an Apple device for now.
- Outbound UDP on port 53 is blocked. All DNS requests should be handled by the dnscrypt_proxy service and if any client, service, etc. tries to circumvent that it is blocked.
