{ config, lib, pkgs, ... }: with lib; let cfg = config.services.transmission; apparmor = config.security.apparmor.enable; homeDir = "/var/lib/transmission"; downloadDir = "${homeDir}/Downloads"; incompleteDir = "${homeDir}/.incomplete"; settingsDir = "${homeDir}/.config/transmission-daemon"; settingsFile = pkgs.writeText "settings.json" (builtins.toJSON fullSettings); # Strings must be quoted, ints and bools must not (for settings.json). toOption = x: if x == true then "true" else if x == false then "false" else if isInt x then toString x else toString ''"${x}"''; # for users in group "transmission" to have access to torrents fullSettings = { umask = 2; download-dir = downloadDir; incomplete-dir = incompleteDir; } // cfg.settings; in { options = { services.transmission = { enable = mkOption { type = types.bool; default = false; description = '' Whether or not to enable the headless Transmission BitTorrent daemon. Transmission daemon can be controlled via the RPC interface using transmission-remote or the WebUI (http://localhost:9091/ by default). Torrents are downloaded to ${downloadDir} by default and are accessible to users in the "transmission" group. ''; }; settings = mkOption { type = types.attrs; default = { download-dir = downloadDir; incomplete-dir = incompleteDir; incomplete-dir-enabled = true; }; example = { download-dir = "/srv/torrents/"; incomplete-dir = "/srv/torrents/.incomplete/"; incomplete-dir-enabled = true; rpc-whitelist = "127.0.0.1,192.168.*.*"; }; description = '' Attribute set whos fields overwrites fields in settings.json (each time the service starts). String values must be quoted, integer and boolean values must not. See https://trac.transmissionbt.com/wiki/EditConfigFiles for documentation. ''; }; port = mkOption { type = types.int; default = 9091; description = "TCP port number to run the RPC/web interface."; }; }; }; config = mkIf cfg.enable { systemd.services.transmission = { description = "Transmission BitTorrent Service"; after = [ "local-fs.target" "network.target" ] ++ optional apparmor "apparmor.service"; requires = mkIf apparmor [ "apparmor.service" ]; wantedBy = [ "multi-user.target" ]; # 1) Only the "transmission" user and group have access to torrents. # 2) Optionally update/force specific fields into the configuration file. serviceConfig.ExecStartPre = '' ${pkgs.stdenv.shell} -c "mkdir -p ${homeDir} ${settingsDir} ${fullSettings.download-dir} ${fullSettings.incomplete-dir} && chmod 770 ${homeDir} ${settingsDir} ${fullSettings.download-dir} ${fullSettings.incomplete-dir} && rm -f ${settingsDir}/settings.json && cp -f ${settingsFile} ${settingsDir}/settings.json" ''; serviceConfig.ExecStart = "${pkgs.transmission}/bin/transmission-daemon -f --port ${toString config.services.transmission.port}"; serviceConfig.ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID"; serviceConfig.User = "transmission"; # NOTE: transmission has an internal umask that also must be set (in settings.json) serviceConfig.UMask = "0002"; }; # It's useful to have transmission in path, e.g. for remote control environment.systemPackages = [ pkgs.transmission ]; users.extraGroups.transmission.gid = config.ids.gids.transmission; users.extraUsers.transmission = { group = "transmission"; uid = config.ids.uids.transmission; description = "Transmission BitTorrent user"; home = homeDir; createHome = true; }; # AppArmor profile security.apparmor.profiles = mkIf apparmor [ (pkgs.writeText "apparmor-transmission-daemon" '' #include ${pkgs.transmission}/bin/transmission-daemon { #include #include ${getLib pkgs.glibc}/lib/*.so mr, ${getLib pkgs.libevent}/lib/libevent*.so* mr, ${getLib pkgs.curl}/lib/libcurl*.so* mr, ${getLib pkgs.openssl}/lib/libssl*.so* mr, ${getLib pkgs.openssl}/lib/libcrypto*.so* mr, ${getLib pkgs.zlib}/lib/libz*.so* mr, ${getLib pkgs.libssh2}/lib/libssh2*.so* mr, ${getLib pkgs.systemd}/lib/libsystemd*.so* mr, ${getLib pkgs.xz}/lib/liblzma*.so* mr, ${getLib pkgs.libgcrypt}/lib/libgcrypt*.so* mr, ${getLib pkgs.libgpgerror}/lib/libgpg-error*.so* mr, ${getLib pkgs.nghttp2}/lib/libnghttp2*.so* mr, ${getLib pkgs.c-ares}/lib/libcares*.so* mr, ${getLib pkgs.libcap}/lib/libcap*.so* mr, ${getLib pkgs.attr}/lib/libattr*.so* mr, ${getLib pkgs.lz4}/lib/liblz4*.so* mr, @{PROC}/sys/kernel/random/uuid r, @{PROC}/sys/vm/overcommit_memory r, ${pkgs.openssl.out}/etc/** r, ${pkgs.transmission}/share/transmission/** r, owner ${settingsDir}/** rw, ${fullSettings.download-dir}/** rw, ${optionalString fullSettings.incomplete-dir-enabled '' ${fullSettings.incomplete-dir}/** rw, ''} } '') ]; }; }