lk/networking/wireguard.md

---
title: "wireguard"
tags: [ "Documentation", "Networking", "VPN" ]
---
<!--
from 
https://engineerworkshop.com/blog/how-to-set-up-wireguard-on-a-raspberry-pi/
-->

## On Server

Install `wireguard-tools` on the server.

```bash
sudo -i
```

```bash
cd /etc/wireguard
```

umask 077

```bash
wg genkey | tee server_private_key | wg pubkey > server_public_key
```

```bash
wg genkey | tee client_private_key | wg pubkey > client_public_key
```

```bash
    echo "
    [Interface]
    Address = 10.0.0.1/24
    SaveConfig = true
    PrivateKey = $(cat server_private_key)
    ListenPort = 51900
    
    PostUp = iptables -A FORWARD -i %i -j ACCEPT; iptables -A FORWARD -o %i -j ACCEPT; iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
    PostDown = iptables -D FORWARD -i %i -j ACCEPT; iptables -D FORWARD -o %i -j ACCEPT; iptables -t nat -D POSTROUTING -o eth0 -j MASQUERADE
    
    [Peer]
    PublicKey = $(cat client_public_key)
    AllowedIPs = 10.0.0.2/32
    " > /etc/wireguard/wg0.conf
```

```bash
echo 'net.ipv4.ip_forward=1' > /etc/sysctl.d/wg.conf
```

```bash
systemctl enable --now wg-quiqck@wg0
```

```bash
chown -R root:root /etc/wireguard/
```

```bash
chmod -R og-rwx /etc/wireguard/\*
```

Forward traffic from port 51900 to the server.

## Client

Be root.

Install `wireguard-tools` on the client.

Copy the client private key and server public key to the server (or just fill in the variables).

> server_ip=*your server's public ip*

    echo "
    [Interface]
    Address = 10.0.0.2/32
    PrivateKey = $(cat client_private_key)
    DNS = 9.9.9.9
    
    [Peer]
    PublicKey = $(cat server_public_key)
    Endpoint = $(echo $server_ip:51900)
    AllowedIPs = 0.0.0.0/0, ::/0
    " > /etc/wireguard/wg0-client.conf

> wg-quick up wg0-client

## Extras

### Multiple Peers

Add multiple peers by copying the `[peer]` section (they each get called `peer`).

### Make a QR Code for Mobile Users

Make a standard client configuration, then:

```bash
qrencode -t ansiutf8 < /etc/wireguard/mobile_user.conf
```