network/nix/nixos-module/container/lxc-config.nix

112 lines
3.3 KiB
Nix

{ config, lib, ... }:
let
inherit (config.networking) hostName;
# linux iface name max length = 15
shortenNetName = name:
if builtins.match "priv(.*)" name != null
then "p" + builtins.substring 4 9 name
else if name == "coloradio"
then "cr"
else if name == "coloradio-gw"
then "cr-gw"
else name;
checkIfname = ifname: let
len = builtins.stringLength ifname;
in if len > 15
then throw "Interface name ${ifname} is ${toString (len - 15)} chars too long."
else ifname;
# `lxc.net.*` formatter for lxc.container.conf files
netConfig = ctName: interfaces:
let
config = map (netName:
let
ifData = interfaces.${netName};
in {
type = ifData.type;
name = checkIfname netName;
flags = "up";
hwaddr = if ifData ? hwaddr && ifData.hwaddr != null
then ifData.hwaddr
else "0A:14:48:xx:xx:xx";
} // (lib.optionalAttrs (ifData.type == "veth") {
veth.pair = checkIfname "${shortenNetName ctName}-${shortenNetName netName}";
veth.mode = checkIfname "bridge";
link = checkIfname netName;
}) // (lib.optionalAttrs (ifData.type == "phys") {
link = checkIfname "ext-${netName}";
})
) (builtins.attrNames interfaces);
attrNamesOrdered = attrs:
if attrs ? type
then [ "type" ] ++ lib.remove "type" (builtins.attrNames attrs)
else builtins.attrNames attrs;
serialize = name: x:
if builtins.isString x
then "${name} = ${x}\n"
else if builtins.isAttrs x
then builtins.concatStringsSep "" (
map (n: serialize "${name}.${n}" x.${n}) (attrNamesOrdered x)
)
else if builtins.isList x
then
let
enumerate = xs: n:
if xs == []
then []
else [ {
e = builtins.head xs;
i = n;
} ] ++ enumerate (builtins.tail xs) (n + 1);
in
builtins.concatStringsSep "" (
map ({ e, i }: serialize "${name}.${toString i}" e) (enumerate x 0)
)
else throw "Invalid data in lxc net config for ${name}: ${lib.generators.toPretty {} x}";
in
serialize "lxc.net" config;
in
{
system.build.lxcConfig = builtins.toFile "${hostName}.conf" ''
# For lxcfs and sane defaults
lxc.include = /etc/lxc/common.conf
lxc.uts.name = ${hostName}
# Handled by lxc@.service
lxc.start.auto = 0
lxc.rootfs.path = /var/lib/lxc/${hostName}/rootfs
lxc.init.cmd = "/init"
lxc.mount.entry = /nix/store nix/store none bind,ro 0 0
lxc.mount.entry = none tmp tmpfs defaults 0 0
lxc.mount.auto = proc:mixed sys:ro cgroup:mixed
lxc.autodev = 1
lxc.tty.max = 0
lxc.pty.max = 8
lxc.cap.drop = sys_module sys_time sys_nice sys_pacct sys_rawio
security.privileged = false
lxc.apparmor.profile = lxc-container-default-with-mounting
lxc.cgroup.memory.limit_in_bytes = 1G
lxc.cgroup.memory.kmem.tcp.limit_in_bytes = 128M
# tuntap
lxc.cgroup.devices.allow = c 10:200 rw
lxc.cgroup2.devices.allow = c 10:200 rw
# ppp
lxc.cgroup.devices.allow = c 108:0 rwm
lxc.cgroup2.devices.allow = c 108:0 rwm
${netConfig hostName config.site.hosts.${hostName}.physicalInterfaces}
'';
}