nixpkgs/nixos/modules/services/mail/opendkim.nix

168 lines
4.6 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.opendkim;
defaultSock = "local:/run/opendkim/opendkim.sock";
keyFile = "${cfg.keyPath}/${cfg.selector}.private";
args = [ "-f" "-l"
"-p" cfg.socket
"-d" cfg.domains
"-k" keyFile
"-s" cfg.selector
] ++ optionals (cfg.configFile != null) [ "-x" cfg.configFile ];
in {
imports = [
(mkRenamedOptionModule [ "services" "opendkim" "keyFile" ] [ "services" "opendkim" "keyPath" ])
];
###### interface
options = {
services.opendkim = {
enable = mkOption {
type = types.bool;
default = false;
description = "Whether to enable the OpenDKIM sender authentication system.";
};
socket = mkOption {
type = types.str;
default = defaultSock;
description = "Socket which is used for communication with OpenDKIM.";
};
user = mkOption {
type = types.str;
default = "opendkim";
description = "User for the daemon.";
};
group = mkOption {
type = types.str;
default = "opendkim";
description = "Group for the daemon.";
};
domains = mkOption {
type = types.str;
default = "csl:${config.networking.hostName}";
defaultText = literalExpression ''"csl:''${config.networking.hostName}"'';
example = "csl:example.com,mydomain.net";
description = ''
Local domains set (see <literal>opendkim(8)</literal> for more information on datasets).
Messages from them are signed, not verified.
'';
};
keyPath = mkOption {
type = types.path;
description = ''
The path that opendkim should put its generated private keys into.
The DNS settings will be found in this directory with the name selector.txt.
'';
default = "/var/lib/opendkim/keys";
};
selector = mkOption {
type = types.str;
description = "Selector to use when signing.";
};
configFile = mkOption {
type = types.nullOr types.path;
default = null;
description = "Additional opendkim configuration.";
};
};
};
###### implementation
config = mkIf cfg.enable {
users.users = optionalAttrs (cfg.user == "opendkim") {
opendkim = {
group = cfg.group;
uid = config.ids.uids.opendkim;
};
};
users.groups = optionalAttrs (cfg.group == "opendkim") {
opendkim.gid = config.ids.gids.opendkim;
};
environment.systemPackages = [ pkgs.opendkim ];
systemd.tmpfiles.rules = [
"d '${cfg.keyPath}' - ${cfg.user} ${cfg.group} - -"
];
systemd.services.opendkim = {
description = "OpenDKIM signing and verification daemon";
after = [ "network.target" ];
wantedBy = [ "multi-user.target" ];
preStart = ''
cd "${cfg.keyPath}"
if ! test -f ${cfg.selector}.private; then
${pkgs.opendkim}/bin/opendkim-genkey -s ${cfg.selector} -d all-domains-generic-key
echo "Generated OpenDKIM key! Please update your DNS settings:\n"
echo "-------------------------------------------------------------"
cat ${cfg.selector}.txt
echo "-------------------------------------------------------------"
fi
'';
serviceConfig = {
ExecStart = "${pkgs.opendkim}/bin/opendkim ${escapeShellArgs args}";
User = cfg.user;
Group = cfg.group;
RuntimeDirectory = optional (cfg.socket == defaultSock) "opendkim";
StateDirectory = "opendkim";
StateDirectoryMode = "0700";
ReadWritePaths = [ cfg.keyPath ];
AmbientCapabilities = [];
CapabilityBoundingSet = "";
DevicePolicy = "closed";
LockPersonality = true;
MemoryDenyWriteExecute = true;
NoNewPrivileges = true;
PrivateDevices = true;
PrivateMounts = true;
PrivateTmp = true;
PrivateUsers = true;
ProtectClock = true;
ProtectControlGroups = true;
ProtectHome = true;
ProtectHostname = true;
ProtectKernelLogs = true;
ProtectKernelModules = true;
ProtectKernelTunables = true;
ProtectSystem = "strict";
RemoveIPC = true;
RestrictAddressFamilies = [ "AF_INET" "AF_INET6 AF_UNIX" ];
RestrictNamespaces = true;
RestrictRealtime = true;
RestrictSUIDSGID = true;
SystemCallArchitectures = "native";
SystemCallFilter = [ "@system-service" "~@privileged @resources" ];
UMask = "0077";
};
};
};
}