diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 69365ca9b72a..23b95ed8d975 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -477,6 +477,7 @@
./services/mail/roundcube.nix
./services/mail/sympa.nix
./services/mail/nullmailer.nix
+ ./services/matrix/mjolnir.nix
./services/matrix/pantalaimon.nix
./services/misc/airsonic.nix
./services/misc/ankisyncd.nix
diff --git a/nixos/modules/services/matrix/mjolnir.nix b/nixos/modules/services/matrix/mjolnir.nix
new file mode 100644
index 000000000000..03ef8def376f
--- /dev/null
+++ b/nixos/modules/services/matrix/mjolnir.nix
@@ -0,0 +1,239 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+let
+ cfg = config.services.mjolnir;
+
+ yamlConfig = {
+ inherit (cfg) dataPath managementRoom protectedRooms;
+
+ accessToken = "@ACCESS_TOKEN@"; # will be replaced in "generateConfig"
+ homeserverUrl =
+ if cfg.pantalaimon.enable then
+ "http://${cfg.pantalaimon.options.listenAddress}:${toString cfg.pantalaimon.options.listenPort}"
+ else
+ cfg.homeserverUrl;
+
+ pantalaimon = {
+ inherit (cfg.pantalaimon) username;
+
+ use = cfg.pantalaimon.enable;
+ password = "@PANTALAIMON_PASSWORD@"; # will be replaced in "generateConfig"
+ };
+ };
+
+ moduleConfigFile = pkgs.writeText "module-config.yaml" (
+ generators.toYAML { } (filterAttrs (_: v: v != null)
+ (fold recursiveUpdate { } [ yamlConfig cfg.settings ])));
+
+ # these config files will be merged one after the other to build the final config
+ configFiles = [
+ "${pkgs.mjolnir}/share/mjolnir/config/default.yaml"
+ moduleConfigFile
+ ];
+
+ # this will generate the default.yaml file with all configFiles as inputs and
+ # replace all secret strings using replace-secret
+ generateConfig = pkgs.writeShellScript "mjolnir-generate-config" (
+ let
+ yqEvalStr = concatImapStringsSep " * " (pos: _: "select(fileIndex == ${toString (pos - 1)})") configFiles;
+ yqEvalArgs = concatStringsSep " " configFiles;
+ in
+ ''
+ set -euo pipefail
+
+ umask 077
+
+ # mjolnir will try to load a config from "./config/default.yaml" in the working directory
+ # -> let's place the generated config there
+ mkdir -p ${cfg.dataPath}/config
+
+ # merge all config files into one, overriding settings of the previous one with the next config
+ # e.g. "eval-all 'select(fileIndex == 0) * select(fileIndex == 1)' filea.yaml fileb.yaml" will merge filea.yaml with fileb.yaml
+ ${pkgs.yq-go}/bin/yq eval-all -P '${yqEvalStr}' ${yqEvalArgs} > ${cfg.dataPath}/config/default.yaml
+
+ ${optionalString (cfg.accessTokenFile != null) ''
+ ${pkgs.replace-secret}/bin/replace-secret '@ACCESS_TOKEN@' '${cfg.accessTokenFile}' ${cfg.dataPath}/config/default.yaml
+ ''}
+ ${optionalString (cfg.pantalaimon.passwordFile != null) ''
+ ${pkgs.replace-secret}/bin/replace-secret '@PANTALAIMON_PASSWORD@' '${cfg.pantalaimon.passwordFile}' ${cfg.dataPath}/config/default.yaml
+ ''}
+ ''
+ );
+in
+{
+ options.services.mjolnir = {
+ enable = mkEnableOption "Mjolnir, a moderation tool for Matrix";
+
+ homeserverUrl = mkOption {
+ type = types.str;
+ default = "https://matrix.org";
+ description = ''
+ Where the homeserver is located (client-server URL).
+
+ If pantalaimon.enable is true, this option will become the homeserver to which pantalaimon connects.
+ The listen address of pantalaimon will then become the homeserverUrl of mjolnir.
+ '';
+ };
+
+ accessTokenFile = mkOption {
+ type = with types; nullOr path;
+ default = null;
+ description = ''
+ File containing the matrix access token for the mjolnir user.
+ '';
+ };
+
+ pantalaimon = mkOption {
+ description = ''
+ pantalaimon options (enables E2E Encryption support).
+
+ This will create a pantalaimon instance with the name "mjolnir".
+ '';
+ default = { };
+ type = types.submodule {
+ options = {
+ enable = mkEnableOption ''
+ If true, accessToken is ignored and the username/password below will be
+ used instead. The access token of the bot will be stored in the dataPath.
+ '';
+
+ username = mkOption {
+ type = types.str;
+ description = "The username to login with.";
+ };
+
+ passwordFile = mkOption {
+ type = with types; nullOr path;
+ default = null;
+ description = ''
+ File containing the matrix password for the mjolnir user.
+ '';
+ };
+
+ options = mkOption {
+ type = types.submodule (import ./pantalaimon-options.nix);
+ default = { };
+ description = ''
+ passthrough additional options to the pantalaimon service.
+ '';
+ };
+ };
+ };
+ };
+
+ dataPath = mkOption {
+ type = types.path;
+ default = "/var/lib/mjolnir";
+ description = ''
+ The directory the bot should store various bits of information in.
+ '';
+ };
+
+ managementRoom = mkOption {
+ type = types.str;
+ default = "#moderators:example.org";
+ description = ''
+ The room ID where people can use the bot. The bot has no access controls, so
+ anyone in this room can use the bot - secure your room!
+ This should be a room alias or room ID - not a matrix.to URL.
+ Note: mjolnir is fairly verbose - expect a lot of messages from it.
+ '';
+ };
+
+ protectedRooms = mkOption {
+ type = types.listOf types.str;
+ default = [ ];
+ example = literalExample ''
+ [
+ "https://matrix.to/#/#yourroom:example.org"
+ "https://matrix.to/#/#anotherroom:example.org"
+ ]
+ '';
+ description = ''
+ A list of rooms to protect (matrix.to URLs).
+ '';
+ };
+
+ settings = mkOption {
+ default = { };
+ type = (pkgs.formats.yaml { }).type;
+ example = literalExample ''
+ {
+ autojoinOnlyIfManager = true;
+ automaticallyRedactForReasons = [ "spam" "advertising" ];
+ }
+ '';
+ description = ''
+ Additional settings (see mjolnir default config for available settings). These settings will override settings made by the module config.
+ '';
+ };
+ };
+
+ config = mkIf config.services.mjolnir.enable {
+ assertions = [
+ {
+ assertion = !(cfg.pantalaimon.enable && cfg.pantalaimon.passwordFile == null);
+ message = "Specify pantalaimon.passwordFile";
+ }
+ {
+ assertion = !(cfg.pantalaimon.enable && cfg.accessTokenFile != null);
+ message = "Do not specify accessTokenFile when using pantalaimon";
+ }
+ {
+ assertion = !(!cfg.pantalaimon.enable && cfg.accessTokenFile == null);
+ message = "Specify accessTokenFile when not using pantalaimon";
+ }
+ ];
+
+ services.pantalaimon-headless.instances."mjolnir" = mkIf cfg.pantalaimon.enable
+ {
+ homeserver = cfg.homeserverUrl;
+ } // cfg.pantalaimon.options;
+
+ systemd.services.mjolnir = {
+ description = "mjolnir - a moderation tool for Matrix";
+ wants = [ "network-online.target" ] ++ optionals (cfg.pantalaimon.enable) [ "pantalaimon-mjolnir.service" ];
+ after = [ "network-online.target" ] ++ optionals (cfg.pantalaimon.enable) [ "pantalaimon-mjolnir.service" ];
+ wantedBy = [ "multi-user.target" ];
+
+ serviceConfig = {
+ ExecStart = ''${pkgs.mjolnir}/bin/mjolnir'';
+ ExecStartPre = [ generateConfig ];
+ WorkingDirectory = cfg.dataPath;
+ StateDirectory = "mjolnir";
+ StateDirectoryMode = "0700";
+ ProtectSystem = "strict";
+ ProtectHome = true;
+ PrivateTmp = true;
+ NoNewPrivileges = true;
+ PrivateDevices = true;
+ User = "mjolnir";
+ Restart = "on-failure";
+
+ /* TODO: wait for #102397 to be resolved. Then load secrets from $CREDENTIALS_DIRECTORY+"/NAME"
+ DynamicUser = true;
+ LoadCredential = [] ++
+ optionals (cfg.accessTokenFile != null) [
+ "access_token:${cfg.accessTokenFile}"
+ ] ++
+ optionals (cfg.pantalaimon.passwordFile != null) [
+ "pantalaimon_password:${cfg.pantalaimon.passwordFile}"
+ ];
+ */
+ };
+ };
+
+ users = {
+ users.mjolnir = {
+ group = "mjolnir";
+ isSystemUser = true;
+ };
+ groups.mjolnir = { };
+ };
+ };
+
+ meta = {
+ maintainers = with maintainers; [ jojosch ];
+ };
+}