#!/bin/sh
set -eu

pid_file="$1"; shift
ip="$1"; shift
mount="$1"; shift
resolv_conf="$1"; shift

printf '%s\n' "$$" > "$pid_file"

while ! "$ip" link show {{.TapName}} >/dev/null 2>&1; do
	sleep 0.02
done

"$mount" --bind "$resolv_conf" /etc/resolv.conf

# fail if we can't add a route, ipv6 is skipped if not enabled on host
for route in{{range .BlockedRoutes}} {{.}}{{end}}; do
	case "$route" in
	*:*) [ -d /proc/sys/net/ipv6 ] || continue ;;
	esac
	"$ip" route add blackhole "$route"
done

exec "$@"