Files
github-action/actions/connect-wireguard/connect-wireguard.sh
T
Tirsvad fce3cf8c6b Add the connect-wireguard composite action for Gitea (not yet verified on a runner)
actions/connect-wireguard brings a WireGuard tunnel up for a deployment job and
takes it down again, with a guide and offline tests. The runs on a real runner
(MIL-012 task 3) are still to do.

Refs #184
Task: MIL-012#3
2026-10-19 11:24:33 +08:00

132 lines
4.8 KiB
Bash

#!/usr/bin/env bash
# Steps of the composite action actions/connect-wireguard/action.yml.
#
# connect-wireguard.sh mask print ::add-mask:: for every secret input
# connect-wireguard.sh up write the configuration and bring the tunnel up
# connect-wireguard.sh down take the tunnel down and delete the configuration
#
# Settings come from the environment, never from interpolated expressions:
# WG_CONFIG, WG_PRIVATE_KEY, WG_ADDRESS, WG_PEER_PUBLIC_KEY, WG_ENDPOINT,
# WG_ALLOWED_IPS, WG_PRESHARED_KEY, WG_DNS, WG_KEEPALIVE, WG_INTERFACE,
# WG_HEALTH_CHECK_HOST. WG_DIR is the configuration directory (/etc/wireguard
# by default); WG_QUICK, WG_SUDO and WG_PING name the commands, for the tests.
# Every failure is printed as ::error::[category] message. A key is never printed.
WG_DIR="${WG_DIR:-/etc/wireguard}"
WG_QUICK="${WG_QUICK:-wg-quick}"
WG_PING="${WG_PING:-ping}"
SUDO="${WG_SUDO-sudo}"
fail() {
echo "::error::[$1] $2"
exit 1
}
mask_secrets() {
local value line
for value in "${WG_PRIVATE_KEY:-}" "${WG_PRESHARED_KEY:-}"; do
[ -n "$value" ] && echo "::add-mask::$value"
done
# every line of a full configuration is masked, so a key cannot leak in pieces
while IFS= read -r line; do
line="${line#"${line%%[![:space:]]*}"}"
[ -n "$line" ] && echo "::add-mask::$line"
done <<<"${WG_CONFIG:-}"
return 0
}
check_interface() {
[[ "$WG_INTERFACE" =~ ^[a-zA-Z0-9_=+.-]{1,15}$ ]] ||
fail configuration "interface '$WG_INTERFACE' is not a valid interface name."
}
# render_config: the wg-quick configuration on stdout
render_config() {
if [ -n "${WG_CONFIG:-}" ]; then
printf '%s\n' "$WG_CONFIG"
return 0
fi
local name
for name in WG_PRIVATE_KEY WG_ADDRESS WG_PEER_PUBLIC_KEY WG_ENDPOINT WG_ALLOWED_IPS; do
[ -n "${!name:-}" ] ||
fail configuration "set config, or all of private-key, address, peer-public-key, endpoint and allowed-ips ($name is empty)."
done
[[ "$WG_KEEPALIVE" =~ ^[0-9]+$ ]] ||
fail configuration "persistent-keepalive must be a number of seconds."
printf '[Interface]\nPrivateKey = %s\nAddress = %s\n' "$WG_PRIVATE_KEY" "$WG_ADDRESS"
[ -z "${WG_DNS:-}" ] || printf 'DNS = %s\n' "$WG_DNS"
printf '\n[Peer]\nPublicKey = %s\nEndpoint = %s\nAllowedIPs = %s\nPersistentKeepalive = %s\n' \
"$WG_PEER_PUBLIC_KEY" "$WG_ENDPOINT" "$WG_ALLOWED_IPS" "$WG_KEEPALIVE"
[ -z "${WG_PRESHARED_KEY:-}" ] || printf 'PresharedKey = %s\n' "$WG_PRESHARED_KEY"
}
install_tools() {
command -v "$WG_QUICK" >/dev/null 2>&1 && return 0
echo "Installing wireguard-tools"
if ! { $SUDO apt-get update -qq &&
$SUDO apt-get install -y -qq wireguard-tools resolvconf iproute2 iputils-ping; }; then
fail environment "wireguard-tools is not installed and could not be installed (a Debian or Ubuntu runner with root is needed)."
fi
}
# Use the user-space implementation when the kernel has no WireGuard module,
# which is the usual case in a Gitea runner container.
choose_implementation() {
if $SUDO ip link add dev "wgprobe$$" type wireguard 2>/dev/null; then
$SUDO ip link delete dev "wgprobe$$" 2>/dev/null || true
return 0
fi
if command -v wireguard-go >/dev/null 2>&1 || $SUDO apt-get install -y -qq wireguard-go 2>/dev/null; then
export WG_QUICK_USERSPACE_IMPLEMENTATION=wireguard-go
echo "No kernel WireGuard module; using wireguard-go."
else
fail environment "the runner has no WireGuard kernel module and wireguard-go could not be installed; the runner container needs NET_ADMIN and /dev/net/tun (see guides/vpn-wireguard.md)."
fi
}
tunnel_up() {
check_interface
local conf="$WG_DIR/$WG_INTERFACE.conf" rendered
# on failure the captured output is the ::error:: line, which must be shown
rendered="$(render_config)" || {
echo "$rendered"
exit 1
}
install_tools
choose_implementation
$SUDO install -d -m 700 "$WG_DIR"
(umask 077 && printf '%s\n' "$rendered" | $SUDO tee "$conf" >/dev/null)
$SUDO chmod 600 "$conf"
$SUDO "$WG_QUICK" up "$WG_INTERFACE" ||
fail connection "wg-quick could not bring $WG_INTERFACE up."
if [ -n "${WG_HEALTH_CHECK_HOST:-}" ]; then
"$WG_PING" -c 3 -W 5 "$WG_HEALTH_CHECK_HOST" >/dev/null 2>&1 ||
fail connection "health-check-host '$WG_HEALTH_CHECK_HOST' does not answer through the tunnel."
fi
echo "WireGuard interface $WG_INTERFACE is up."
}
tunnel_down() {
check_interface
local conf="$WG_DIR/$WG_INTERFACE.conf"
$SUDO "$WG_QUICK" down "$WG_INTERFACE" 2>/dev/null || echo "Interface $WG_INTERFACE was not up."
$SUDO rm -f "$conf"
echo "WireGuard interface $WG_INTERFACE is down."
}
main() {
set -uo pipefail
WG_INTERFACE="${WG_INTERFACE:-wg0}"
WG_KEEPALIVE="${WG_KEEPALIVE:-25}"
case "${1:-}" in
mask) mask_secrets ;;
up) tunnel_up ;;
down) tunnel_down ;;
*) fail configuration "unknown command '${1:-}'; use mask, up or down." ;;
esac
}
if [ "${BASH_SOURCE[0]}" = "$0" ]; then
main "$@"
fi