dsnet/README.md

dsnet is a simple configuration tool to manage a centralised wireguard VPN.
Think wg-quick but quicker. From scratch:

![dsnet add](https://raw.githubusercontent.com/naggie/dsnet/master/etc/init+add.png)

The server peer is listening, and a client peer config has been generated and
added to the server peer:

![wg](https://raw.githubusercontent.com/naggie/dsnet/master/etc/wg2.png)

More client peers can be added with `dsnet add`. They can connect immediately after!

It works on AMD64 based linux and also ARMv5.

    Usage: dsnet <cmd>

    Available commands:

    	init   : Create /etc/dsnetconfig.json containing default configuration + new keys without loading. Edit to taste.
    	add    : Add a new peer + sync
    	up     : Create the interface, run pre/post up, sync
    	report : Generate a JSON status report to the location configured in /etc/dsnetconfig.json.
    	remove : Remove a peer by hostname provided as argument + sync
    	down   : Destroy the interface, run pre/post down
    	sync   : Update wireguard configuration from /etc/dsnetconfig.json after validating


Quick start (AMD64 linux) -- install wireguard, then, after making sure `/usr/local/bin` is in your path:

    sudo wget https://github.com/naggie/dsnet/releases/download/v0.1/dsnet-linux-amd64 -O /usr/local/bin/dsnet
    sudo chmod +x /usr/local/bin/dsnet
    sudo dsnet init
    # edit /etc/dsnetconfig.json to taste
    sudo dsnet up
	sudo dsnet add banana > dsnet-banana.conf
	sudo dsnet add apple > dsnet-apple.conf

Copy the generated configuration file to your device and connect!

To send configurations, ffsend (with separately transferred password) or a
local QR code generator may be used.

The peer private key is generated on the server, which is technically not as
secure as generating it on the client peer and then providing the server the
public key; there is provision to specify a public key in the code when adding
a peer to avoid the server generating the private key. The feature will be
added when requested.

# Configuration overview

dsnetconfig.json is the only file the server needs to run the VPN. It contains
the server keys, peer public/shared keys and IP settings. **A working version is
automatically generated by `dsnet init` which can be modified as required.**

Currently its location is fixed as all my deployments are for a single network.
I may add a feature to allow setting of the location via environment variable
in the future to support multiple networks on a single host.

Main configuration example:


    {
        "ExternalIP": "198.51.100.2",
        "ListenPort": 51820,
        "Domain": "dsnet",
        "InterfaceName": "dsnet",
        "Network": "10.164.236.0/22",
        "IP": "10.164.236.1",
        "DNS": "",
        "Networks": [],
        "ReportFile": "/var/lib/dsnetreport.json",
        "PrivateKey": "uC+xz3v1mfjWBHepwiCgAmPebZcY+EdhaHAvqX2r7U8=",
        "Peers": [
            {
                "Hostname": "test",
                "Owner": "naggie",
                "Description": "Home server",
                "IP": "10.164.236.2",
                "Added": "2020-05-07T10:04:46.336286992+01:00",
                "Networks": [],
                "PublicKey": "altJeQ/V52JZQrGcA9RiKcpZusYU6zMUJhl7Wbd9rX0=",
                "PresharedKey": "GcUtlze0BMuxo3iVEjpOahKdTf8xVfF8hDW3Ylw5az0="
            }
        ]
    }

Explanation of each field:

    {
        "ExternalIP": "198.51.100.2",

This is the external IP that will be the value of Endpoint for the server peer
in client configs. It is automatically detected by opening a socket or using an
external IP discovery service -- the first to give a valid public IPv4 will
win.


        "ListenPort": 51820,

The port wiregard should listen on.

        "Domain": "dsnet",

The domain to copy to the report file. Not used for anything else; it's useful
for DNS integration. At one site I have a script to add hosts to a zone upon
connection by polling the report file.

        "InterfaceName": "dsnet",

The wireguard interface name.

        "Network": "10.164.236.0/22",

The CIDR network to use when allocating IPs to peers. This subnet, a `/22` in
the `10.0.0.0/16` block is generated randomly to (probably) avoid collisions
with other networks. There are 1022 addresses available. Addresses are
allocated to peers when peers are added with `dsnet add` using the lowest
available address.

        "IP": "10.164.236.1",

This is the private VPN IP of the server peer. It is the first address in the
above pool.

        "DNS": "",

If defined, this IP address will be set in the generated peer wg-quick config
files.

        "Networks": [],

This is a list of additional CIDR-notated networks that can be routed through
the server peer. They will be added under the server peer under `AllowedIPs` in
addition to the private network defined in `Network` above. If you want to
route the whole internet through the server peer, add `0.0.0.0/0` to the list
before adding peers. For more advanced options and theory, see
<https://www.wireguard.com/netns/>.

        "ReportFile": "/var/lib/dsnetreport.json",

This is the location of the report file generated with `dsnet report`. It is
suggested that this command is run via a cron job; the report can be safely
consumed by a web service or DNS integration script, for instance.

The report contains no sensitive information. At one site I use it together
with [hugo](https://gohugo.io/)
[shortcodes](https://gohugo.io/templates/shortcode-templates/) to generate a
network overview page. The shortcode file is included in this repository under
`etc/`.

        "PrivateKey": "uC+xz3v1mfjWBHepwiCgAmPebZcY+EdhaHAvqX2r7U8=",

The server private key, automatically generated and very sensitive!

        "Peers": []

The list of peers managed by `dsnet add` and `dsnet remove`. See below for format.

    }

The configuration file can be manually/programatically managed outside of dsnet
if desired; `dsnet sync` will update wireguard.

Peer configuration, `Peers: []` in `dsnetconfig.json`:

        {
            "Hostname": "test",

The hostname given via `dsnet add <hostname>`. It is used to identify the peer
in the report and for peer removal via `dsnet remove <hostname>`. It can also
be used to update a DNS zone via a custom script that operates on the report
file as mentioned above.

            "Owner": "naggie",

The owner of the peer, copied to the report file.

            "Description": "Home server",

A description of the peer, copied to the report file; the lack of which in
`wq-quick` is what inspired me to write dsnet in the first place.


            "IP": "10.164.236.2",

The private VPN IP allocated by dsnet for this peer. It is the lowest available
IP in the pool from `Network`, above.

            "Added": "2020-05-07T10:04:46.336286992+01:00",

The timestamp of when the peer was added by dsnet.

            "Networks": [],

Any other CIDR networks that can be routed through this peer.

            "PublicKey": "altJeQ/V52JZQrGcA9RiKcpZusYU6zMUJhl7Wbd9rX0=",

The public key derived from the private key generated by dsnet when the peer
was added.

            "PresharedKey": "GcUtlze0BMuxo3iVEjpOahKdTf8xVfF8hDW3Ylw5az0="

The pre-shared key for this peer. The peer has the same key defined as the
pre-shared key for the server peer. This is optional in wireguard but not for
dsnet due to the extra (post quantum!) security it provides.


        }

# Report file overview

An example report file, generated by `dsnet report` to
`/var/lib/dsnetreport.json` by default:

    {
        "ExternalIP": "198.51.100.2",
        "InterfaceName": "dsnet",
        "ListenPort": 51820,
        "Domain": "dsnet",
        "IP": "10.164.236.1",
        "Network": "10.164.236.0/22",
        "DNS": "",
        "PeersOnline": 4,
        "PeersTotal": 13,
        "ReceiveBytes": 32517164,
        "TransmitBytes": 85384984,
        "ReceiveBytesSI": "32.5 MB",
        "TransmitBytesSI": "85.4 MB",
        "Peers": [
            {
                "Hostname": "test",
                "Owner": "naggie",
                "Description": "Home server",
                "Online": false,
                "Dormant": true,
                "Added": "2020-03-12T20:15:42.798800741Z",
                "IP": "10.164.236.2",
                "ExternalIP": "198.51.100.223",
                "Networks": [],
                "Added": "2020-05-07T10:04:46.336286992+01:00",
                "ReceiveBytes": 32517164,
                "TransmitBytes": 85384984,
                "ReceiveBytesSI": "32.5 MB",
                "TransmitBytesSI": "85.4 MB"
            }

            <...>
        ]
    }

Fields mean the same as they do above, or are self explanatory. Note that some
data is converted into human readable formats in addition to machine formats --
this is technically redundant but useful with Hugo shortcodes and other site generators.

The report can be converted, for instance, into a HTML table as below:

![dsnet report table](https://raw.githubusercontent.com/naggie/dsnet/master/etc/report.png)

See
[etc/README.md](https://github.com/naggie/dsnet/blob/master/contrib/report_rendering/README.md)
for hugo and PHP code for rendering a similar table.

# FAQ

> Does dsnet support IPv6?

Not currently but this is a [planned feature](https://github.com/naggie/dsnet/issues/1).

> Is dsnet production ready?

Absolutely, it's just a configuration generator so your VPN does not depend on
dsnet after adding peers. I use it in production at 2 companies so far.

Note that before version 1.0, the config file schema may change. Changes will
be made clear in release notes.

> Why are there very few issues?

I'm tracking development elsewhere using
[dstask](https://github.com/naggie/dstask). I keep public initiated issues on
github though, and will probably migrate issues over if this gains use outside
of what I'm doing.

> Client private keys are generated on the server. Can I avoid this?

Allowing generation of the pub/priv keypair on the client is not yet supported,
but will be soon as provision exists within the code base. Note that whilst
client peer private keys are generated on the server, they are never stored.


> How do I get dsnet to bring the (server) interface up on startup?

Assuming you're running a systemd powered linux distribution (most of them are):

1. Copy
   [etc/dsnet.service](https://github.com/naggie/dsnet/blob/master/etc/dsnet.service)
   to `/etc/systemd/system/`
2. Run `sudo systemctl daemon-reload` to get systemd to see it
3. Then run `sudo systemctl enable dsnet` to enable it at boot

> How can I generate the report periodically?

Either with cron or a systemd timer. Cron is easiest:

    echo '* * * * * root /usr/local/bin/dsnet report | sudo tee /etc/cron.d/dsnetreport'

Note that whilst report generation requires root, consuming the report does not
as it's just a world-readable file. This is important for web interfaces that
need to be secure.

This is also why dsnet loads its configuration from a file -- it's possible to
set permissions such that dsnet synchronises the config generated by a non-root
user. Combined with a periodic `dsnet sync` like above, it's possible to build
a secure web interface that does not require root. A web interface is currently
being created by a friend; it will not be part of dstask, rather a separate
project.