diff options
Diffstat (limited to 'nixpkgs/nixos/modules/services/networking/yggdrasil.nix')
| -rw-r--r-- | nixpkgs/nixos/modules/services/networking/yggdrasil.nix | 227 |
1 files changed, 127 insertions, 100 deletions
diff --git a/nixpkgs/nixos/modules/services/networking/yggdrasil.nix b/nixpkgs/nixos/modules/services/networking/yggdrasil.nix index 81ed6d1dd566..55a6002d61af 100644 --- a/nixpkgs/nixos/modules/services/networking/yggdrasil.nix +++ b/nixpkgs/nixos/modules/services/networking/yggdrasil.nix @@ -8,7 +8,8 @@ let configFileProvided = cfg.configFile != null; format = pkgs.formats.json { }; -in { +in +{ imports = [ (mkRenamedOptionModule [ "services" "yggdrasil" "config" ] @@ -17,11 +18,11 @@ in { options = with types; { services.yggdrasil = { - enable = mkEnableOption "the yggdrasil system service"; + enable = mkEnableOption (lib.mdDoc "the yggdrasil system service"); settings = mkOption { type = format.type; - default = {}; + default = { }; example = { Peers = [ "tcp://aa.bb.cc.dd:eeeee" @@ -31,29 +32,28 @@ in { "tcp://0.0.0.0:xxxxx" ]; }; - description = '' + description = lib.mdDoc '' Configuration for yggdrasil, as a Nix attribute set. Warning: this is stored in the WORLD-READABLE Nix store! Therefore, it is not appropriate for private keys. If you - wish to specify the keys, use <option>configFile</option>. + wish to specify the keys, use {option}`configFile`. - If the <option>persistentKeys</option> is enabled then the + If the {option}`persistentKeys` is enabled then the keys that are generated during activation will override - those in <option>config</option> or - <option>configFile</option>. + those in {option}`settings` or + {option}`configFile`. If no keys are specified then ephemeral keys are generated and the Yggdrasil interface will have a random IPv6 address - each time the service is started, this is the default. + each time the service is started. This is the default. - If both <option>configFile</option> and <option>config</option> + If both {option}`configFile` and {option}`settings` are supplied, they will be combined, with values from - <option>configFile</option> taking precedence. + {option}`configFile` taking precedence. - You can use the command <literal>nix-shell -p yggdrasil --run - "yggdrasil -genconf"</literal> to generate default - configuration values with documentation. + You can use the command `nix-shell -p yggdrasil --run "yggdrasil -genconf"` + to generate default configuration values with documentation. ''; }; @@ -62,8 +62,13 @@ in { default = null; example = "/run/keys/yggdrasil.conf"; description = lib.mdDoc '' - A file which contains JSON configuration for yggdrasil. - See the {option}`config` option for more information. + A file which contains JSON or HJSON configuration for yggdrasil. See + the {option}`settings` option for more information. + + Note: This file must not be larger than 1 MB because it is passed to + the yggdrasil process via systemd‘s LoadCredential mechanism. For + details, see <https://systemd.io/CREDENTIALS/> and `man 5 + systemd.exec`. ''; }; @@ -78,20 +83,20 @@ in { type = bool; default = false; description = lib.mdDoc '' - Whether to open the UDP port used for multicast peer - discovery. The NixOS firewall blocks link-local - communication, so in order to make local peering work you - will also need to set `LinkLocalTCPPort` in your - yggdrasil configuration ({option}`config` or - {option}`configFile`) to a port number other than 0, - and then add that port to - {option}`networking.firewall.allowedTCPPorts`. + Whether to open the UDP port used for multicast peer discovery. The + NixOS firewall blocks link-local communication, so in order to make + incoming local peering work you will also need to configure + `MulticastInterfaces` in your Yggdrasil configuration + ({option}`settings` or {option}`configFile`). You will then have to + add the ports that you configure there to your firewall configuration + ({option}`networking.firewall.allowedTCPPorts` or + {option}`networking.firewall.interfaces.<name>.allowedTCPPorts`). ''; }; denyDhcpcdInterfaces = mkOption { type = listOf str; - default = []; + default = [ ]; example = [ "tap*" ]; description = lib.mdDoc '' Disable the DHCP client for any interface whose name matches @@ -110,91 +115,113 @@ in { description = lib.mdDoc "Yggdrasil package to use."; }; - persistentKeys = mkEnableOption '' + persistentKeys = mkEnableOption (lib.mdDoc '' If enabled then keys will be generated once and Yggdrasil will retain the same IPv6 address when the service is restarted. Keys are stored at ${keysPath}. - ''; + ''); }; }; - config = mkIf cfg.enable (let binYggdrasil = cfg.package + "/bin/yggdrasil"; - in { - assertions = [{ - assertion = config.networking.enableIPv6; - message = "networking.enableIPv6 must be true for yggdrasil to work"; - }]; - - system.activationScripts.yggdrasil = mkIf cfg.persistentKeys '' - if [ ! -e ${keysPath} ] - then - mkdir --mode=700 -p ${builtins.dirOf keysPath} - ${binYggdrasil} -genconf -json \ - | ${pkgs.jq}/bin/jq \ - 'to_entries|map(select(.key|endswith("Key")))|from_entries' \ - > ${keysPath} - fi - ''; - - systemd.services.yggdrasil = { - description = "Yggdrasil Network Service"; - after = [ "network-pre.target" ]; - wants = [ "network.target" ]; - before = [ "network.target" ]; - wantedBy = [ "multi-user.target" ]; - - preStart = - (if settingsProvided || configFileProvided || cfg.persistentKeys then - "echo " - - + (lib.optionalString settingsProvided - "'${builtins.toJSON cfg.settings}'") - + (lib.optionalString configFileProvided "$(cat ${cfg.configFile})") - + (lib.optionalString cfg.persistentKeys "$(cat ${keysPath})") - + " | ${pkgs.jq}/bin/jq -s add | ${binYggdrasil} -normaliseconf -useconf" - else - "${binYggdrasil} -genconf") + " > /run/yggdrasil/yggdrasil.conf"; - - serviceConfig = { - ExecStart = - "${binYggdrasil} -useconffile /run/yggdrasil/yggdrasil.conf"; - ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID"; - Restart = "always"; - - DynamicUser = true; - StateDirectory = "yggdrasil"; - RuntimeDirectory = "yggdrasil"; - RuntimeDirectoryMode = "0750"; - BindReadOnlyPaths = lib.optional configFileProvided cfg.configFile - ++ lib.optional cfg.persistentKeys keysPath; - ReadWritePaths = "/run/yggdrasil"; - - AmbientCapabilities = "CAP_NET_ADMIN CAP_NET_BIND_SERVICE"; - CapabilityBoundingSet = "CAP_NET_ADMIN CAP_NET_BIND_SERVICE"; - MemoryDenyWriteExecute = true; - ProtectControlGroups = true; - ProtectHome = "tmpfs"; - ProtectKernelModules = true; - ProtectKernelTunables = true; - RestrictAddressFamilies = "AF_UNIX AF_INET AF_INET6 AF_NETLINK"; - RestrictNamespaces = true; - RestrictRealtime = true; - SystemCallArchitectures = "native"; - SystemCallFilter = "~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io @resources"; - } // (if (cfg.group != null) then { - Group = cfg.group; - } else {}); - }; + config = mkIf cfg.enable ( + let + binYggdrasil = "${cfg.package}/bin/yggdrasil"; + binHjson = "${pkgs.hjson-go}/bin/hjson-cli"; + in + { + assertions = [{ + assertion = config.networking.enableIPv6; + message = "networking.enableIPv6 must be true for yggdrasil to work"; + }]; + + system.activationScripts.yggdrasil = mkIf cfg.persistentKeys '' + if [ ! -e ${keysPath} ] + then + mkdir --mode=700 -p ${builtins.dirOf keysPath} + ${binYggdrasil} -genconf -json \ + | ${pkgs.jq}/bin/jq \ + 'to_entries|map(select(.key|endswith("Key")))|from_entries' \ + > ${keysPath} + fi + ''; + + systemd.services.yggdrasil = { + description = "Yggdrasil Network Service"; + after = [ "network-pre.target" ]; + wants = [ "network.target" ]; + before = [ "network.target" ]; + wantedBy = [ "multi-user.target" ]; + + # This script first prepares the config file, then it starts Yggdrasil. + # The preparation could also be done in ExecStartPre/preStart but only + # systemd versions >= v252 support reading credentials in ExecStartPre. As + # of February 2023, systemd v252 is not yet in the stable branch of NixOS. + # + # This could be changed in the future once systemd version v252 has + # reached NixOS but it does not have to be. Config file preparation is + # fast enough, it does not need elevated privileges, and `set -euo + # pipefail` should make sure that the service is not started if the + # preparation fails. Therefore, it is not necessary to move the + # preparation to ExecStartPre. + script = '' + set -euo pipefail + + # prepare config file + ${(if settingsProvided || configFileProvided || cfg.persistentKeys then + "echo " + + + (lib.optionalString settingsProvided + "'${builtins.toJSON cfg.settings}'") + + (lib.optionalString configFileProvided + "$(${binHjson} -c \"$CREDENTIALS_DIRECTORY/yggdrasil.conf\")") + + (lib.optionalString cfg.persistentKeys "$(cat ${keysPath})") + + " | ${pkgs.jq}/bin/jq -s add | ${binYggdrasil} -normaliseconf -useconf" + else + "${binYggdrasil} -genconf") + " > /run/yggdrasil/yggdrasil.conf"} + + # start yggdrasil + ${binYggdrasil} -useconffile /run/yggdrasil/yggdrasil.conf + ''; + + serviceConfig = { + ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID"; + Restart = "always"; + + DynamicUser = true; + StateDirectory = "yggdrasil"; + RuntimeDirectory = "yggdrasil"; + RuntimeDirectoryMode = "0750"; + BindReadOnlyPaths = lib.optional cfg.persistentKeys keysPath; + LoadCredential = + mkIf configFileProvided "yggdrasil.conf:${cfg.configFile}"; + + AmbientCapabilities = "CAP_NET_ADMIN CAP_NET_BIND_SERVICE"; + CapabilityBoundingSet = "CAP_NET_ADMIN CAP_NET_BIND_SERVICE"; + MemoryDenyWriteExecute = true; + ProtectControlGroups = true; + ProtectHome = "tmpfs"; + ProtectKernelModules = true; + ProtectKernelTunables = true; + RestrictAddressFamilies = "AF_UNIX AF_INET AF_INET6 AF_NETLINK"; + RestrictNamespaces = true; + RestrictRealtime = true; + SystemCallArchitectures = "native"; + SystemCallFilter = [ "@system-service" "~@privileged @keyring" ]; + } // (if (cfg.group != null) then { + Group = cfg.group; + } else { }); + }; - networking.dhcpcd.denyInterfaces = cfg.denyDhcpcdInterfaces; - networking.firewall.allowedUDPPorts = mkIf cfg.openMulticastPort [ 9001 ]; + networking.dhcpcd.denyInterfaces = cfg.denyDhcpcdInterfaces; + networking.firewall.allowedUDPPorts = mkIf cfg.openMulticastPort [ 9001 ]; - # Make yggdrasilctl available on the command line. - environment.systemPackages = [ cfg.package ]; - }); + # Make yggdrasilctl available on the command line. + environment.systemPackages = [ cfg.package ]; + } + ); meta = { - doc = ./yggdrasil.xml; + doc = ./yggdrasil.md; maintainers = with lib.maintainers; [ gazally ehmry ]; }; } |