Innernet – A private network system that uses WireGuard under the hood

A private network system that uses WireGuard under the hood. See the announcement blog post for a longer-winded explanation.

innernet is similar in its goals to Slack's nebula or Tailscale, but takes a bit of a different approach. It aims to take advantage of existing networking concepts like CIDRs and the security properties of WireGuard to turn your computer's basic IP networking into more powerful ACL primitives.

innernet is not an official WireGuard project, and WireGuard is a registered trademark of Jason A. Donenfeld.

This has not received an independent security audit, and should be considered experimental software at this early point in its lifetime.

Every innernet network needs a coordination server to manage peers and provide endpoint information so peers can directly connect to each other. Create a new one with

The init wizard will ask you questions about your network and give you some reasonable defaults. It's good to familiarize yourself with network CIDRs as a lot of innernet's access control is based upon them. As an example, let's say the root CIDR for this network is 10.60.0.0/16. Server initialization creates a special "infra" CIDR which contains the innernet server itself and is reachable from all CIDRs on the network.

Next we'll also create a humans CIDR where we can start adding some peers.

For the parent CIDR, you can simply choose your network's root CIDR. The name will be humans, and the CIDR will be 10.60.64.0/24 (not a great example unless you only want to support 256 humans, but it works for now...).

By default, peers which exist in this new CIDR will only be able to contact peers in the same CIDR, and the special "infra" CIDR which was created when the server was initialized.

A typical workflow for creating a new network is to create an admin peer from the innernet-server CLI, and then continue using that admin peer via the innernet client CLI to add any further peers or network CIDRs.

Select the humans CIDR, and the CLI will automatically suggest the next available IP address. Any name is fine, just answer "yes" when asked if you would like to make the peer an admin. The process of adding a peer results in an invitation file. This file contains just enough information for the new peer to contact the innernet server and redeem its invitation. It should be transferred securely to the new peer, and it can only be used once to initialize the peer.

You can run the server with innernet-server serve <interface>, or if you're on Linux and want to run it via systemctl, run systemctl enable --now innernet-server@<interface>. If you're on a home network, don't forget to configure port forwarding to the Listen Port you specified when creating the innernet server.

Let's assume the invitation file generated in the steps above have been transferred to the machine a network admin will be using.

You can initialize the client with

You can customize the network name if you want to, or leave it at the default. innernet will then connect to the innernet server via WireGuard, generate a new key pair, and register that pair with the server. The private key in the invitation file can no longer be used.

If everything was successful, the new peer is on the network. You can run things like

or

to view the current network and all CIDRs visible to this peer.

Since we created an admin peer, we can also add new peers and CIDRs from this peer via innernet instead of having to always run commands on the server.

In order for peers from one CIDR to be able to contact peers in another CIDR, those two CIDRs must be "associated" with each other.

With the admin peer we created above, let's add a new CIDR for some theoretical CI servers we have.

The name is ci-servers and the CIDR is 10.60.64.0/24, but for this example it can be anything.

For now, we want peers in the humans CIDR to be able to access peers in the ci-servers CIDR.

The CLI will ask you to select the two CIDRs you want to associate. That's all it takes to allow peers in two different CIDRs to communicate!

You can verify the association with

and associations can be deleted with

For security reasons, IP addresses cannot be re-used by new peers, and therefore peers cannot be deleted. However, they can be disabled. Disabled peers will not show up in the list of peers when fetching the config for an interface.

Disable a peer with

Or re-enable a peer with

The innernet server will try to use the internet endpoint it sees from a peer so other peers can connect to that peer as well. This doesn't always work and you may want to set an endpoint explicitly. To set an endpoint, use

You can go back to automatic endpoint discovery with

If you want to change the port which WireGuard listens on, use

or unset the port and use a randomized port with

To permanently uninstall a created network, use

Use with care!

If you're running a service on innernet, there are some important security considerations.

Strict RPF prevents packets from other interfaces from having internal source IP addresses. This is not the default on Linux, even though it is the right choice for 99.99% of situations. You can enable it by adding the following to a /etc/sysctl.d/60-network-security.conf:

If possible, to ensure that packets are only ever transmitted over the WireGuard interface, it's recommended that you use SO_BINDTODEVICE on Linux or IP_BOUND_IF on macOS/BSDs. If you have strict reverse path filtering, though, this is less of a concern.

Even following all the above precautions, rogue applications on a peer's machines could be able to make requests on their behalf unless you add extra layers of authentication to mitigate this CSRF-type vector.

It's recommended that you carefully consider this possibility before deciding that the source IP is sufficient for your authentication needs on a service.

innernet has only officially been tested on Linux and MacOS, but we hope to support as many platforms as is feasible!

It's assumed that WireGuard is installed on your system, either via the kernel module in Linux 5.6 and later, or via the wireguard-go userspace implementation.

WireGuard Installation Instructions

@tommie is kindly providing Debian/Ubuntu innernet builds in the https://github.com/tommie/innernet-debian repository.

We're looking for volunteers who are able to set up external builds for popular distributions. Please see issue #203.

Note that you'll be responsible for updating manually.

If your target system uses SELinux, you will want to enable the 'selinux' feature when building the innernet binary. This will ensure that innernet maintains the correct selinux context on the /etc/hosts file when adding hosts. To do so add --features selinux to the cargo build options. The selinux-devel package will need to be installed for the correct headers.

• rustc / cargo (version 1.50.0 or higher)
• libclang (see more info at https://crates.io/crates/clang-sys)
• libsqlite3

Build:

The resulting binary will be located at ./target/release/innernet-server

• rustc / cargo (version 1.50.0 or higher)
• libclang (see more info at https://crates.io/crates/clang-sys)

Build:

The resulting binary will be located at ./target/release/innernet

You can manually invoke Docker-based tests assuming you have Docker daemon running. If you specify --interactive flag, it allows you to attach to the server and client innernet Docker containers, so you can test various innernet commands inside a sandboxed environment.

If you are developing a new feature, please consider adding a new test case to run-docker-tests.sh (example PR).

Please run the release script from a Linux machine: generated shell completions depend on available wireguard backends and Mac doesn't support the kernel backend.

1. Fetch and check-out the main branch.
2. Run ./release.sh [patch|major|minor|rc]
3. Push the main branch and the created tag to the repo.
4. Publish crates that have publish = true to crates.io.