nixpkgs/nixos/modules/services/networking/fastnetmon-advanced.nix
2023-10-23 22:51:19 +02:00

223 lines
8.5 KiB
Nix

{ config, lib, pkgs, ... }:
let
# Background information: FastNetMon requires a MongoDB to start. This is because
# it uses MongoDB to store its configuration. That is, in a normal setup there is
# one collection with one document.
# To provide declarative configuration in our NixOS module, this database is
# completely emptied and replaced on each boot by the fastnetmon-setup service
# using the configuration backup functionality.
cfg = config.services.fastnetmon-advanced;
settingsFormat = pkgs.formats.yaml { };
# obtain the default configs by starting up ferretdb and fcli in a derivation
default_configs = pkgs.runCommand "default-configs" {
nativeBuildInputs = [
pkgs.ferretdb
pkgs.fastnetmon-advanced # for fcli
pkgs.proot
];
} ''
mkdir ferretdb fastnetmon $out
FERRETDB_TELEMETRY="disable" FERRETDB_HANDLER="sqlite" FERRETDB_STATE_DIR="$PWD/ferretdb" FERRETDB_SQLITE_URL="file:$PWD/ferretdb/" ferretdb &
cat << EOF > fastnetmon/fastnetmon.conf
${builtins.toJSON {
mongodb_username = "";
}}
EOF
proot -b fastnetmon:/etc/fastnetmon -0 fcli create_configuration
proot -b fastnetmon:/etc/fastnetmon -0 fcli set bgp default
proot -b fastnetmon:/etc/fastnetmon -0 fcli export_configuration backup.tar
tar -C $out --no-same-owner -xvf backup.tar
'';
# merge the user configs into the default configs
config_tar = pkgs.runCommand "fastnetmon-config.tar" {
nativeBuildInputs = with pkgs; [ jq ];
} ''
jq -s add ${default_configs}/main.json ${pkgs.writeText "main-add.json" (builtins.toJSON cfg.settings)} > main.json
mkdir hostgroup
${lib.concatImapStringsSep "\n" (pos: hostgroup: ''
jq -s add ${default_configs}/hostgroup/0.json ${pkgs.writeText "hostgroup-${toString (pos - 1)}-add.json" (builtins.toJSON hostgroup)} > hostgroup/${toString (pos - 1)}.json
'') hostgroups}
mkdir bgp
${lib.concatImapStringsSep "\n" (pos: bgp: ''
jq -s add ${default_configs}/bgp/0.json ${pkgs.writeText "bgp-${toString (pos - 1)}-add.json" (builtins.toJSON bgp)} > bgp/${toString (pos - 1)}.json
'') bgpPeers}
tar -cf $out main.json ${lib.concatImapStringsSep " " (pos: _: "hostgroup/${toString (pos - 1)}.json") hostgroups} ${lib.concatImapStringsSep " " (pos: _: "bgp/${toString (pos - 1)}.json") bgpPeers}
'';
hostgroups = lib.mapAttrsToList (name: hostgroup: { inherit name; } // hostgroup) cfg.hostgroups;
bgpPeers = lib.mapAttrsToList (name: bgpPeer: { inherit name; } // bgpPeer) cfg.bgpPeers;
in {
options.services.fastnetmon-advanced = with lib; {
enable = mkEnableOption "the fastnetmon-advanced DDoS Protection daemon";
settings = mkOption {
description = ''
Extra configuration options to declaratively load into FastNetMon Advanced.
See the [FastNetMon Advanced Configuration options reference](https://fastnetmon.com/docs-fnm-advanced/fastnetmon-advanced-configuration-options/) for more details.
'';
type = settingsFormat.type;
default = {};
example = literalExpression ''
{
networks_list = [ "192.0.2.0/24" ];
gobgp = true;
gobgp_flow_spec_announces = true;
}
'';
};
hostgroups = mkOption {
description = "Hostgroups to declaratively load into FastNetMon Advanced";
type = types.attrsOf settingsFormat.type;
default = {};
};
bgpPeers = mkOption {
description = "BGP Peers to declaratively load into FastNetMon Advanced";
type = types.attrsOf settingsFormat.type;
default = {};
};
enableAdvancedTrafficPersistence = mkOption {
description = "Store historical flow data in clickhouse";
type = types.bool;
default = false;
};
traffic_db.settings = mkOption {
type = settingsFormat.type;
description = "Additional settings for /etc/fastnetmon/traffic_db.conf";
};
};
config = lib.mkMerge [ (lib.mkIf cfg.enable {
environment.systemPackages = with pkgs; [
fastnetmon-advanced # for fcli
];
environment.etc."fastnetmon/license.lic".source = "/var/lib/fastnetmon/license.lic";
environment.etc."fastnetmon/gobgpd.conf".source = "/run/fastnetmon/gobgpd.conf";
environment.etc."fastnetmon/fastnetmon.conf".source = pkgs.writeText "fastnetmon.conf" (builtins.toJSON {
mongodb_username = "";
});
services.ferretdb.enable = true;
systemd.services.fastnetmon-setup = {
wantedBy = [ "multi-user.target" ];
after = [ "ferretdb.service" ];
path = with pkgs; [ fastnetmon-advanced config.systemd.package ];
script = ''
fcli create_configuration
fcli delete hostgroup global
fcli import_configuration ${config_tar}
systemctl --no-block try-restart fastnetmon
'';
serviceConfig.Type = "oneshot";
};
systemd.services.fastnetmon = {
wantedBy = [ "multi-user.target" ];
after = [ "ferretdb.service" "fastnetmon-setup.service" "polkit.service" ];
path = with pkgs; [ iproute2 ];
unitConfig = {
# Disable logic which shuts service when we do too many restarts
# We do restarts from sudo fcli commit and it's expected that we may have many restarts
# Details: https://github.com/systemd/systemd/issues/2416
StartLimitInterval = 0;
};
serviceConfig = {
ExecStart = "${pkgs.fastnetmon-advanced}/bin/fastnetmon --log_to_console";
LimitNOFILE = 65535;
# Restart service when it fails due to any reasons, we need to keep processing traffic no matter what happened
Restart= "on-failure";
RestartSec= "5s";
DynamicUser = true;
CacheDirectory = "fastnetmon";
RuntimeDirectory = "fastnetmon"; # for gobgpd config
StateDirectory = "fastnetmon"; # for license file
};
};
security.polkit.enable = true;
security.polkit.extraConfig = ''
polkit.addRule(function(action, subject) {
if (action.id == "org.freedesktop.systemd1.manage-units" &&
subject.isInGroup("fastnetmon")) {
if (action.lookup("unit") == "gobgp.service") {
var verb = action.lookup("verb");
if (verb == "start" || verb == "stop" || verb == "restart") {
return polkit.Result.YES;
}
}
}
});
'';
# We don't use the existing gobgp NixOS module and package, because the gobgp
# version might not be compatible with fastnetmon. Also, the service name
# _must_ be 'gobgp' and not 'gobgpd', so that fastnetmon can reload the config.
systemd.services.gobgp = {
wantedBy = [ "multi-user.target" ];
after = [ "network.target" ];
description = "GoBGP Routing Daemon";
unitConfig = {
ConditionPathExists = "/run/fastnetmon/gobgpd.conf";
};
serviceConfig = {
Type = "notify";
ExecStartPre = "${pkgs.fastnetmon-advanced}/bin/fnm-gobgpd -f /run/fastnetmon/gobgpd.conf -d";
SupplementaryGroups = [ "fastnetmon" ];
ExecStart = "${pkgs.fastnetmon-advanced}/bin/fnm-gobgpd -f /run/fastnetmon/gobgpd.conf --sdnotify";
ExecReload = "${pkgs.fastnetmon-advanced}/bin/fnm-gobgpd -r";
DynamicUser = true;
AmbientCapabilities = "cap_net_bind_service";
};
};
})
(lib.mkIf (cfg.enable && cfg.enableAdvancedTrafficPersistence) {
## Advanced Traffic persistence
## https://fastnetmon.com/docs-fnm-advanced/fastnetmon-advanced-traffic-persistency/
services.clickhouse.enable = true;
services.fastnetmon-advanced.settings.traffic_db = true;
services.fastnetmon-advanced.traffic_db.settings = {
clickhouse_batch_size = lib.mkDefault 1000;
clickhouse_batch_delay = lib.mkDefault 1;
traffic_db_host = lib.mkDefault "127.0.0.1";
traffic_db_port = lib.mkDefault 8100;
clickhouse_host = lib.mkDefault "127.0.0.1";
clickhouse_port = lib.mkDefault 9000;
clickhouse_user = lib.mkDefault "default";
clickhouse_password = lib.mkDefault "";
};
environment.etc."fastnetmon/traffic_db.conf".text = builtins.toJSON cfg.traffic_db.settings;
systemd.services.traffic_db = {
wantedBy = [ "multi-user.target" ];
after = [ "network.target" ];
serviceConfig = {
ExecStart = "${pkgs.fastnetmon-advanced}/bin/traffic_db";
# Restart service when it fails due to any reasons, we need to keep processing traffic no matter what happened
Restart= "on-failure";
RestartSec= "5s";
DynamicUser = true;
};
};
}) ];
meta.maintainers = lib.teams.wdz.members;
}