nixpkgs/nixos/modules/services/networking/ndppd.nix
2023-04-07 13:38:33 +02:00

190 lines
6.1 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.ndppd;
render = s: f: concatStringsSep "\n" (mapAttrsToList f s);
prefer = a: b: if a != null then a else b;
ndppdConf = prefer cfg.configFile (pkgs.writeText "ndppd.conf" ''
route-ttl ${toString cfg.routeTTL}
${render cfg.proxies (proxyInterfaceName: proxy: ''
proxy ${prefer proxy.interface proxyInterfaceName} {
router ${boolToString proxy.router}
timeout ${toString proxy.timeout}
ttl ${toString proxy.ttl}
${render proxy.rules (ruleNetworkName: rule: ''
rule ${prefer rule.network ruleNetworkName} {
${rule.method}${optionalString (rule.method == "iface") " ${rule.interface}"}
}'')}
}'')}
'');
proxy = types.submodule {
options = {
interface = mkOption {
type = types.nullOr types.str;
description = lib.mdDoc ''
Listen for any Neighbor Solicitation messages on this interface,
and respond to them according to a set of rules.
Defaults to the name of the attrset.
'';
default = null;
};
router = mkOption {
type = types.bool;
description = lib.mdDoc ''
Turns on or off the router flag for Neighbor Advertisement Messages.
'';
default = true;
};
timeout = mkOption {
type = types.int;
description = lib.mdDoc ''
Controls how long to wait for a Neighbor Advertisement Message before
invalidating the entry, in milliseconds.
'';
default = 500;
};
ttl = mkOption {
type = types.int;
description = lib.mdDoc ''
Controls how long a valid or invalid entry remains in the cache, in
milliseconds.
'';
default = 30000;
};
rules = mkOption {
type = types.attrsOf rule;
description = lib.mdDoc ''
This is a rule that the target address is to match against. If no netmask
is provided, /128 is assumed. You may have several rule sections, and the
addresses may or may not overlap.
'';
default = {};
};
};
};
rule = types.submodule {
options = {
network = mkOption {
type = types.nullOr types.str;
description = lib.mdDoc ''
This is the target address is to match against. If no netmask
is provided, /128 is assumed. The addresses of several rules
may or may not overlap.
Defaults to the name of the attrset.
'';
default = null;
};
method = mkOption {
type = types.enum [ "static" "iface" "auto" ];
description = lib.mdDoc ''
static: Immediately answer any Neighbor Solicitation Messages
(if they match the IP rule).
iface: Forward the Neighbor Solicitation Message through the specified
interface and only respond if a matching Neighbor Advertisement
Message is received.
auto: Same as iface, but instead of manually specifying the outgoing
interface, check for a matching route in /proc/net/ipv6_route.
'';
default = "auto";
};
interface = mkOption {
type = types.nullOr types.str;
description = lib.mdDoc "Interface to use when method is iface.";
default = null;
};
};
};
in {
options.services.ndppd = {
enable = mkEnableOption (lib.mdDoc "daemon that proxies NDP (Neighbor Discovery Protocol) messages between interfaces");
interface = mkOption {
type = types.nullOr types.str;
description = lib.mdDoc ''
Interface which is on link-level with router.
(Legacy option, use services.ndppd.proxies.\<interface\>.rules.\<network\> instead)
'';
default = null;
example = "eth0";
};
network = mkOption {
type = types.nullOr types.str;
description = lib.mdDoc ''
Network that we proxy.
(Legacy option, use services.ndppd.proxies.\<interface\>.rules.\<network\> instead)
'';
default = null;
example = "1111::/64";
};
configFile = mkOption {
type = types.nullOr types.path;
description = lib.mdDoc "Path to configuration file.";
default = null;
};
routeTTL = mkOption {
type = types.int;
description = lib.mdDoc ''
This tells 'ndppd' how often to reload the route file /proc/net/ipv6_route,
in milliseconds.
'';
default = 30000;
};
proxies = mkOption {
type = types.attrsOf proxy;
description = lib.mdDoc ''
This sets up a listener, that will listen for any Neighbor Solicitation
messages, and respond to them according to a set of rules.
'';
default = {};
example = literalExpression ''
{
eth0.rules."1111::/64" = {};
}
'';
};
};
config = mkIf cfg.enable {
warnings = mkIf (cfg.interface != null && cfg.network != null) [ ''
The options services.ndppd.interface and services.ndppd.network will probably be removed soon,
please use services.ndppd.proxies.<interface>.rules.<network> instead.
'' ];
services.ndppd.proxies = mkIf (cfg.interface != null && cfg.network != null) {
${cfg.interface}.rules.${cfg.network} = {};
};
systemd.services.ndppd = {
description = "NDP Proxy Daemon";
documentation = [ "man:ndppd(1)" "man:ndppd.conf(5)" ];
after = [ "network-pre.target" ];
wantedBy = [ "multi-user.target" ];
serviceConfig = {
ExecStart = "${pkgs.ndppd}/bin/ndppd -c ${ndppdConf}";
# Sandboxing
CapabilityBoundingSet = "CAP_NET_RAW CAP_NET_ADMIN";
ProtectSystem = "strict";
ProtectHome = true;
PrivateTmp = true;
PrivateDevices = true;
ProtectKernelTunables = true;
ProtectKernelModules = true;
ProtectControlGroups = true;
RestrictAddressFamilies = "AF_INET6 AF_PACKET AF_NETLINK";
RestrictNamespaces = true;
LockPersonality = true;
MemoryDenyWriteExecute = true;
RestrictRealtime = true;
RestrictSUIDSGID = true;
};
};
};
}