nixos-config/system/vpn.nix

118 lines
4 KiB
Nix

{
config,
pkgs,
lib,
...
}:
let
cfg = config.services.tailscale;
tailscaleInterface = cfg.interfaceName;
inherit (config.networking) hostName;
tailnetHost = "${hostName}.tail05275.ts.net";
in
{
networking.wireguard.enable = true;
networking.firewall.trustedInterfaces = [ tailscaleInterface ];
systemd.network = {
# Fixes issues with other systemd networks when tailscale exist nodes are used
config.networkConfig = {
ManageForeignRoutes = false;
ManageForeignRoutingPolicyRules = false;
};
wait-online.ignoredInterfaces = [ "tailscale0" ];
};
services.networkd-dispatcher = {
enable = true;
rules = {
# exclude LANs from tailscale subnet routes (when using `--accept-routes`)
"50-tailscale-exclude-lan-routes" = {
onState = [ "routable" ];
script = ''
#!${pkgs.runtimeShell}
# shellcheck disable=SC2010
lan_interfaces=$(ls /sys/class/net | grep -E '^(enp|eth|wlp)')
if [[ "$lan_interfaces" == "" ]]; then exit 0; fi
echo "$lan_interfaces" | while IFS= read -r lan_if; do
for ipv in 4 6; do
subnets=$(${pkgs.iproute2}/bin/ip -"$ipv" route show dev "$lan_if" proto kernel | cut -f1 -d' ' | grep '/')
if [[ "$subnets" == "" ]]; then break; fi
echo "$subnets" | while IFS= read -r subnet; do
if ${pkgs.iproute2}/bin/ip -"$ipv" route show table 52 | grep -q "$subnet dev tailscale0"; then
${pkgs.iproute2}/bin/ip -"$ipv" route del "$subnet" dev tailscale0 table 52
${pkgs.iproute2}/bin/ip -"$ipv" route add throw "$subnet" table 52
fi
done
done
done
'';
};
# UDP throughput improvements
# https://tailscale.com/kb/1320/performance-best-practices?q=gro#linux-optimizations-for-subnet-routers-and-exit-nodes
"50-tailscale-rx-udp-gro-forwarding" = {
onState = [ "routable" ];
script = ''
for dev in $(${pkgs.iproute2}/bin/ip route show 0/0 | cut -f5 -d' '); do
${lib.getExe pkgs.ethtool} -K "$dev" rx-udp-gro-forwarding on rx-gro-list off
done
'';
};
};
};
services.tailscale = {
enable = true;
package = pkgs.unstable.tailscale;
openFirewall = true;
useRoutingFeatures = lib.mkDefault "client";
extraUpFlags = [
"--reset"
"--exit-node-allow-lan-access"
"--exit-node=de-fra-wg-106.mullvad.ts.net"
];
};
systemd.services.tailscaled = {
serviceConfig.Environment = [ "TS_DEBUG_FIREWALL_MODE=auto" ];
after = [
"network-online.target"
"systemd-resolved.service"
];
};
# call taiscale up without --auth-key
systemd.services.tailscaled-autoconnect = lib.mkIf (cfg.authKeyFile == null) {
after = [ "tailscaled.service" ];
wants = [ "tailscaled.service" ];
wantedBy = [ "multi-user.target" ];
serviceConfig.Type = "oneshot";
script =
''
status=$(${config.systemd.package}/bin/systemctl show -P StatusText tailscaled.service)
if [[ $status != Connected* ]]; then
${cfg.package}/bin/tailscale up
fi
# some options cannot be set immediately
${cfg.package}/bin/tailscale up ${lib.escapeShellArgs cfg.extraUpFlags}
${cfg.package}/bin/tailscale cert ${tailnetHost}
''
+ lib.optionalString config.services.nginx.enable ''
chown nginx:nginx /var/lib/tailscale/certs/${tailnetHost}.{key,crt}
'';
};
services.nginx.virtualHosts.${tailnetHost} = {
sslCertificate = "/var/lib/tailscale/certs/${tailnetHost}.crt";
sslCertificateKey = "/var/lib/tailscale/certs/${tailnetHost}.key";
};
# TODO Tailscale Mullvad exit nodes currently don't support IPv6 and this is
# causing issues with nginx (proxy pass) requests timing out and high CPU load.
# Until Mullvad exit nodes support IPv6, we'll just disable IPv6 for nginx.
services.nginx.resolver.ipv6 = false;
}