diff options
Diffstat (limited to 'nixos/modules/services/games/minecraft-server.nix')
| -rw-r--r-- | nixos/modules/services/games/minecraft-server.nix | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/nixos/modules/services/games/minecraft-server.nix b/nixos/modules/services/games/minecraft-server.nix new file mode 100644 index 00000000000..5bb8eff5762 --- /dev/null +++ b/nixos/modules/services/games/minecraft-server.nix @@ -0,0 +1,257 @@ +{ config, lib, pkgs, ... }: + +with lib; + +let + cfg = config.services.minecraft-server; + + # We don't allow eula=false anyways + eulaFile = builtins.toFile "eula.txt" '' + # eula.txt managed by NixOS Configuration + eula=true + ''; + + whitelistFile = pkgs.writeText "whitelist.json" + (builtins.toJSON + (mapAttrsToList (n: v: { name = n; uuid = v; }) cfg.whitelist)); + + cfgToString = v: if builtins.isBool v then boolToString v else toString v; + + serverPropertiesFile = pkgs.writeText "server.properties" ('' + # server.properties managed by NixOS configuration + '' + concatStringsSep "\n" (mapAttrsToList + (n: v: "${n}=${cfgToString v}") cfg.serverProperties)); + + + # To be able to open the firewall, we need to read out port values in the + # server properties, but fall back to the defaults when those don't exist. + # These defaults are from https://minecraft.gamepedia.com/Server.properties#Java_Edition_3 + defaultServerPort = 25565; + + serverPort = cfg.serverProperties.server-port or defaultServerPort; + + rconPort = if cfg.serverProperties.enable-rcon or false + then cfg.serverProperties."rcon.port" or 25575 + else null; + + queryPort = if cfg.serverProperties.enable-query or false + then cfg.serverProperties."query.port" or 25565 + else null; + +in { + options = { + services.minecraft-server = { + + enable = mkOption { + type = types.bool; + default = false; + description = '' + If enabled, start a Minecraft Server. The server + data will be loaded from and saved to + <option>services.minecraft-server.dataDir</option>. + ''; + }; + + declarative = mkOption { + type = types.bool; + default = false; + description = '' + Whether to use a declarative Minecraft server configuration. + Only if set to <literal>true</literal>, the options + <option>services.minecraft-server.whitelist</option> and + <option>services.minecraft-server.serverProperties</option> will be + applied. + ''; + }; + + eula = mkOption { + type = types.bool; + default = false; + description = '' + Whether you agree to + <link xlink:href="https://account.mojang.com/documents/minecraft_eula"> + Mojangs EULA</link>. This option must be set to + <literal>true</literal> to run Minecraft server. + ''; + }; + + dataDir = mkOption { + type = types.path; + default = "/var/lib/minecraft"; + description = '' + Directory to store Minecraft database and other state/data files. + ''; + }; + + openFirewall = mkOption { + type = types.bool; + default = false; + description = '' + Whether to open ports in the firewall for the server. + ''; + }; + + whitelist = mkOption { + type = let + minecraftUUID = types.strMatching + "[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}" // { + description = "Minecraft UUID"; + }; + in types.attrsOf minecraftUUID; + default = {}; + description = '' + Whitelisted players, only has an effect when + <option>services.minecraft-server.declarative</option> is + <literal>true</literal> and the whitelist is enabled + via <option>services.minecraft-server.serverProperties</option> by + setting <literal>white-list</literal> to <literal>true</literal>. + This is a mapping from Minecraft usernames to UUIDs. + You can use <link xlink:href="https://mcuuid.net/"/> to get a + Minecraft UUID for a username. + ''; + example = literalExpression '' + { + username1 = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"; + username2 = "yyyyyyyy-yyyy-yyyy-yyyy-yyyyyyyyyyyy"; + }; + ''; + }; + + serverProperties = mkOption { + type = with types; attrsOf (oneOf [ bool int str ]); + default = {}; + example = literalExpression '' + { + server-port = 43000; + difficulty = 3; + gamemode = 1; + max-players = 5; + motd = "NixOS Minecraft server!"; + white-list = true; + enable-rcon = true; + "rcon.password" = "hunter2"; + } + ''; + description = '' + Minecraft server properties for the server.properties file. Only has + an effect when <option>services.minecraft-server.declarative</option> + is set to <literal>true</literal>. See + <link xlink:href="https://minecraft.gamepedia.com/Server.properties#Java_Edition_3"/> + for documentation on these values. + ''; + }; + + package = mkOption { + type = types.package; + default = pkgs.minecraft-server; + defaultText = literalExpression "pkgs.minecraft-server"; + example = literalExpression "pkgs.minecraft-server_1_12_2"; + description = "Version of minecraft-server to run."; + }; + + jvmOpts = mkOption { + type = types.separatedString " "; + default = "-Xmx2048M -Xms2048M"; + # Example options from https://minecraft.gamepedia.com/Tutorials/Server_startup_script + example = "-Xmx2048M -Xms4092M -XX:+UseG1GC -XX:+CMSIncrementalPacing " + + "-XX:+CMSClassUnloadingEnabled -XX:ParallelGCThreads=2 " + + "-XX:MinHeapFreeRatio=5 -XX:MaxHeapFreeRatio=10"; + description = "JVM options for the Minecraft server."; + }; + }; + }; + + config = mkIf cfg.enable { + + users.users.minecraft = { + description = "Minecraft server service user"; + home = cfg.dataDir; + createHome = true; + isSystemUser = true; + group = "minecraft"; + }; + users.groups.minecraft = {}; + + systemd.services.minecraft-server = { + description = "Minecraft Server Service"; + wantedBy = [ "multi-user.target" ]; + after = [ "network.target" ]; + + serviceConfig = { + ExecStart = "${cfg.package}/bin/minecraft-server ${cfg.jvmOpts}"; + Restart = "always"; + User = "minecraft"; + WorkingDirectory = cfg.dataDir; + # Hardening + CapabilityBoundingSet = [ "" ]; + DeviceAllow = [ "" ]; + LockPersonality = true; + PrivateDevices = true; + PrivateTmp = true; + PrivateUsers = true; + ProtectClock = true; + ProtectControlGroups = true; + ProtectHome = true; + ProtectHostname = true; + ProtectKernelLogs = true; + ProtectKernelModules = true; + ProtectKernelTunables = true; + ProtectProc = "invisible"; + RestrictAddressFamilies = [ "AF_INET" "AF_INET6" ]; + RestrictNamespaces = true; + RestrictRealtime = true; + RestrictSUIDSGID = true; + SystemCallArchitectures = "native"; + UMask = "0077"; + }; + + preStart = '' + ln -sf ${eulaFile} eula.txt + '' + (if cfg.declarative then '' + + if [ -e .declarative ]; then + + # Was declarative before, no need to back up anything + ln -sf ${whitelistFile} whitelist.json + cp -f ${serverPropertiesFile} server.properties + + else + + # Declarative for the first time, backup stateful files + ln -sb --suffix=.stateful ${whitelistFile} whitelist.json + cp -b --suffix=.stateful ${serverPropertiesFile} server.properties + + # server.properties must have write permissions, because every time + # the server starts it first parses the file and then regenerates it.. + chmod +w server.properties + echo "Autogenerated file that signifies that this server configuration is managed declaratively by NixOS" \ + > .declarative + + fi + '' else '' + if [ -e .declarative ]; then + rm .declarative + fi + ''); + }; + + networking.firewall = mkIf cfg.openFirewall (if cfg.declarative then { + allowedUDPPorts = [ serverPort ]; + allowedTCPPorts = [ serverPort ] + ++ optional (queryPort != null) queryPort + ++ optional (rconPort != null) rconPort; + } else { + allowedUDPPorts = [ defaultServerPort ]; + allowedTCPPorts = [ defaultServerPort ]; + }); + + assertions = [ + { assertion = cfg.eula; + message = "You must agree to Mojangs EULA to run minecraft-server." + + " Read https://account.mojang.com/documents/minecraft_eula and" + + " set `services.minecraft-server.eula` to `true` if you agree."; + } + ]; + + }; +} |