Generate kubernetes wireguard client based on helm chart

generate_kubernetes_wireguard_peer.sh

#!/bin/bash

# MIT License
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# Copyright (c) 2024 Robin Landström
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# Based on Robin Landström code, tool to generate clients for https://github.com/bryopsida/wireguard-chart/ helm chart

# Generate peer keys
readonly PRIVATE_KEY=$(wg genkey)
readonly PUBLIC_KEY=$(echo ${PRIVATE_KEY} | wg pubkey)
readonly PRESHARED_KEY=$(wg genpsk)

# Read server key from interface 
# UPDATE ACCORDINGLY 
readonly SERVER_PUBLIC_KEY=$(sudo kubectl -n wireguard get secrets wg-vpn-1-wg-generated -o jsonpath='{.data.privatekey}' | base64 --decode | wg pubkey)


# Generate peer config QR code
cat << END_OF_CONFIG
# server configuration

[Peer]

PublicKey = $PUBLIC_KEY
PresharedKey = ${PRESHARED_KEY}
AllowedIPs = 10.10.10.0/24 allowed mask i.e.: 10.34.0.3

# Client configuration

[Interface]
Address = $1 #parameter address to be set for this peer
PrivateKey = ${PRIVATE_KEY}
# UPDATE ACCORDINGLY 
DNS = 10.43.0.10 # This is kube-dns default dns


[Peer]
PublicKey = ${SERVER_PUBLIC_KEY}
PresharedKey = ${PRESHARED_KEY}
# UPDATE ACCORDINGLY 
AllowedIPs = allowed mask
Endpoint = <update your endpoint>:<port>
END_OF_CONFIG