nixpkgs/nixos/modules/services/networking/rdnssd.nix
Nikolay Amiantov 01b90dce78 resolvconf service: init
This is a refactor of how resolvconf is managed on NixOS. We split it
into a separate service which is enabled internally depending on whether
we want /etc/resolv.conf to be managed by it. Various services now take
advantage of those configuration options.

We also now use systemd instead of activation scripts to update
resolv.conf.

NetworkManager now uses the right option for rc-manager DNS
automatically, so the configuration option shouldn't be exposed.
2019-07-15 20:25:39 +03:00

80 lines
1.9 KiB
Nix

# Module for rdnssd, a daemon that configures DNS servers in
# /etc/resolv/conf from IPv6 RDNSS advertisements.
{ config, lib, pkgs, ... }:
with lib;
let
mergeHook = pkgs.writeScript "rdnssd-merge-hook" ''
#! ${pkgs.runtimeShell} -e
${pkgs.openresolv}/bin/resolvconf -u
'';
in
{
###### interface
options = {
services.rdnssd.enable = mkOption {
default = false;
#default = config.networking.enableIPv6;
description =
''
Whether to enable the RDNSS daemon
(<command>rdnssd</command>), which configures DNS servers in
<filename>/etc/resolv.conf</filename> from RDNSS
advertisements sent by IPv6 routers.
'';
};
};
###### implementation
config = mkIf config.services.rdnssd.enable {
assertions = [{
assertion = config.networking.resolvconf.enable;
message = "rdnssd needs resolvconf to work (probably something sets up a static resolv.conf)";
}];
systemd.services.rdnssd = {
description = "RDNSS daemon";
after = [ "network.target" ];
wantedBy = [ "multi-user.target" ];
preStart = ''
# Create the proper run directory
mkdir -p /run/rdnssd
touch /run/rdnssd/resolv.conf
chown -R rdnssd /run/rdnssd
# Link the resolvconf interfaces to rdnssd
rm -f /run/resolvconf/interfaces/rdnssd
ln -s /run/rdnssd/resolv.conf /run/resolvconf/interfaces/rdnssd
${mergeHook}
'';
postStop = ''
rm -f /run/resolvconf/interfaces/rdnssd
${mergeHook}
'';
serviceConfig = {
ExecStart = "@${pkgs.ndisc6}/bin/rdnssd rdnssd -p /run/rdnssd/rdnssd.pid -r /run/rdnssd/resolv.conf -u rdnssd -H ${mergeHook}";
Type = "forking";
PIDFile = "/run/rdnssd/rdnssd.pid";
};
};
users.users.rdnssd = {
description = "RDNSSD Daemon User";
uid = config.ids.uids.rdnssd;
};
};
}