diff options
Diffstat (limited to 'nixos/modules/services/security/kanidm.nix')
| -rw-r--r-- | nixos/modules/services/security/kanidm.nix | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/nixos/modules/services/security/kanidm.nix b/nixos/modules/services/security/kanidm.nix new file mode 100644 index 00000000000..a7c51b9a877 --- /dev/null +++ b/nixos/modules/services/security/kanidm.nix @@ -0,0 +1,345 @@ +{ config, lib, options, pkgs, ... }: +let + cfg = config.services.kanidm; + settingsFormat = pkgs.formats.toml { }; + # Remove null values, so we can document optional values that don't end up in the generated TOML file. + filterConfig = lib.converge (lib.filterAttrsRecursive (_: v: v != null)); + serverConfigFile = settingsFormat.generate "server.toml" (filterConfig cfg.serverSettings); + clientConfigFile = settingsFormat.generate "kanidm-config.toml" (filterConfig cfg.clientSettings); + unixConfigFile = settingsFormat.generate "kanidm-unixd.toml" (filterConfig cfg.unixSettings); + + defaultServiceConfig = { + BindReadOnlyPaths = [ + "/nix/store" + "-/etc/resolv.conf" + "-/etc/nsswitch.conf" + "-/etc/hosts" + "-/etc/localtime" + ]; + CapabilityBoundingSet = ""; + # ProtectClock= adds DeviceAllow=char-rtc r + DeviceAllow = ""; + # Implies ProtectSystem=strict, which re-mounts all paths + # DynamicUser = true; + LockPersonality = true; + MemoryDenyWriteExecute = true; + NoNewPrivileges = true; + PrivateDevices = true; + PrivateMounts = true; + PrivateNetwork = true; + PrivateTmp = true; + PrivateUsers = true; + ProcSubset = "pid"; + ProtectClock = true; + ProtectHome = true; + ProtectHostname = true; + # Would re-mount paths ignored by temporary root + #ProtectSystem = "strict"; + ProtectControlGroups = true; + ProtectKernelLogs = true; + ProtectKernelModules = true; + ProtectKernelTunables = true; + ProtectProc = "invisible"; + RestrictAddressFamilies = [ ]; + RestrictNamespaces = true; + RestrictRealtime = true; + RestrictSUIDSGID = true; + SystemCallArchitectures = "native"; + SystemCallFilter = [ "@system-service" "~@privileged @resources @setuid @keyring" ]; + # Does not work well with the temporary root + #UMask = "0066"; + }; + +in +{ + options.services.kanidm = { + enableClient = lib.mkEnableOption "the Kanidm client"; + enableServer = lib.mkEnableOption "the Kanidm server"; + enablePam = lib.mkEnableOption "the Kanidm PAM and NSS integration."; + + serverSettings = lib.mkOption { + type = lib.types.submodule { + freeformType = settingsFormat.type; + + options = { + bindaddress = lib.mkOption { + description = "Address/port combination the webserver binds to."; + example = "[::1]:8443"; + type = lib.types.str; + }; + # Should be optional but toml does not accept null + ldapbindaddress = lib.mkOption { + description = '' + Address and port the LDAP server is bound to. Setting this to <literal>null</literal> disables the LDAP interface. + ''; + example = "[::1]:636"; + default = null; + type = lib.types.nullOr lib.types.str; + }; + origin = lib.mkOption { + description = "The origin of your Kanidm instance. Must have https as protocol."; + example = "https://idm.example.org"; + type = lib.types.strMatching "^https://.*"; + }; + domain = lib.mkOption { + description = '' + The <literal>domain</literal> that Kanidm manages. Must be below or equal to the domain + specified in <literal>serverSettings.origin</literal>. + This can be left at <literal>null</literal>, only if your instance has the role <literal>ReadOnlyReplica</literal>. + While it is possible to change the domain later on, it requires extra steps! + Please consider the warnings and execute the steps described + <link xlink:href="https://kanidm.github.io/kanidm/stable/administrivia.html#rename-the-domain">in the documentation</link>. + ''; + example = "example.org"; + default = null; + type = lib.types.nullOr lib.types.str; + }; + db_path = lib.mkOption { + description = "Path to Kanidm database."; + default = "/var/lib/kanidm/kanidm.db"; + readOnly = true; + type = lib.types.path; + }; + log_level = lib.mkOption { + description = "Log level of the server."; + default = "default"; + type = lib.types.enum [ "default" "verbose" "perfbasic" "perffull" ]; + }; + role = lib.mkOption { + description = "The role of this server. This affects the replication relationship and thereby available features."; + default = "WriteReplica"; + type = lib.types.enum [ "WriteReplica" "WriteReplicaNoUI" "ReadOnlyReplica" ]; + }; + }; + }; + default = { }; + description = '' + Settings for Kanidm, see + <link xlink:href="https://github.com/kanidm/kanidm/blob/master/kanidm_book/src/server_configuration.md">the documentation</link> + and <link xlink:href="https://github.com/kanidm/kanidm/blob/master/examples/server.toml">example configuration</link> + for possible values. + ''; + }; + + clientSettings = lib.mkOption { + type = lib.types.submodule { + freeformType = settingsFormat.type; + + options.uri = lib.mkOption { + description = "Address of the Kanidm server."; + example = "http://127.0.0.1:8080"; + type = lib.types.str; + }; + }; + description = '' + Configure Kanidm clients, needed for the PAM daemon. See + <link xlink:href="https://github.com/kanidm/kanidm/blob/master/kanidm_book/src/client_tools.md#kanidm-configuration">the documentation</link> + and <link xlink:href="https://github.com/kanidm/kanidm/blob/master/examples/config">example configuration</link> + for possible values. + ''; + }; + + unixSettings = lib.mkOption { + type = lib.types.submodule { + freeformType = settingsFormat.type; + + options.pam_allowed_login_groups = lib.mkOption { + description = "Kanidm groups that are allowed to login using PAM."; + example = "my_pam_group"; + type = lib.types.listOf lib.types.str; + }; + }; + description = '' + Configure Kanidm unix daemon. + See <link xlink:href="https://github.com/kanidm/kanidm/blob/master/kanidm_book/src/pam_and_nsswitch.md#the-unix-daemon">the documentation</link> + and <link xlink:href="https://github.com/kanidm/kanidm/blob/master/examples/unixd">example configuration</link> + for possible values. + ''; + }; + }; + + config = lib.mkIf (cfg.enableClient || cfg.enableServer || cfg.enablePam) { + assertions = + [ + { + assertion = !cfg.enableServer || ((cfg.serverSettings.tls_chain or null) == null) || (!lib.isStorePath cfg.serverSettings.tls_chain); + message = '' + <option>services.kanidm.serverSettings.tls_chain</option> points to + a file in the Nix store. You should use a quoted absolute path to + prevent this. + ''; + } + { + assertion = !cfg.enableServer || ((cfg.serverSettings.tls_key or null) == null) || (!lib.isStorePath cfg.serverSettings.tls_key); + message = '' + <option>services.kanidm.serverSettings.tls_key</option> points to + a file in the Nix store. You should use a quoted absolute path to + prevent this. + ''; + } + { + assertion = !cfg.enableClient || options.services.kanidm.clientSettings.isDefined; + message = '' + <option>services.kanidm.clientSettings</option> needs to be configured + if the client is enabled. + ''; + } + { + assertion = !cfg.enablePam || options.services.kanidm.clientSettings.isDefined; + message = '' + <option>services.kanidm.clientSettings</option> needs to be configured + for the PAM daemon to connect to the Kanidm server. + ''; + } + { + assertion = !cfg.enableServer || (cfg.serverSettings.domain == null + -> cfg.serverSettings.role == "WriteReplica" || cfg.serverSettings.role == "WriteReplicaNoUI"); + message = '' + <option>services.kanidm.serverSettings.domain</option> can only be set if this instance + is not a ReadOnlyReplica. Otherwise the db would inherit it from + the instance it follows. + ''; + } + ]; + + environment.systemPackages = lib.mkIf cfg.enableClient [ pkgs.kanidm ]; + + systemd.services.kanidm = lib.mkIf cfg.enableServer { + description = "kanidm identity management daemon"; + wantedBy = [ "multi-user.target" ]; + after = [ "network.target" ]; + serviceConfig = defaultServiceConfig // { + StateDirectory = "kanidm"; + StateDirectoryMode = "0700"; + ExecStart = "${pkgs.kanidm}/bin/kanidmd server -c ${serverConfigFile}"; + User = "kanidm"; + Group = "kanidm"; + + AmbientCapabilities = [ "CAP_NET_BIND_SERVICE" ]; + CapabilityBoundingSet = [ "CAP_NET_BIND_SERVICE" ]; + # This would otherwise override the CAP_NET_BIND_SERVICE capability. + PrivateUsers = false; + # Port needs to be exposed to the host network + PrivateNetwork = false; + RestrictAddressFamilies = [ "AF_INET" "AF_INET6" ]; + TemporaryFileSystem = "/:ro"; + }; + environment.RUST_LOG = "info"; + }; + + systemd.services.kanidm-unixd = lib.mkIf cfg.enablePam { + description = "Kanidm PAM daemon"; + wantedBy = [ "multi-user.target" ]; + after = [ "network.target" ]; + restartTriggers = [ unixConfigFile clientConfigFile ]; + serviceConfig = defaultServiceConfig // { + CacheDirectory = "kanidm-unixd"; + CacheDirectoryMode = "0700"; + RuntimeDirectory = "kanidm-unixd"; + ExecStart = "${pkgs.kanidm}/bin/kanidm_unixd"; + User = "kanidm-unixd"; + Group = "kanidm-unixd"; + + BindReadOnlyPaths = [ + "/nix/store" + "-/etc/resolv.conf" + "-/etc/nsswitch.conf" + "-/etc/hosts" + "-/etc/localtime" + "-/etc/kanidm" + "-/etc/static/kanidm" + ]; + BindPaths = [ + # To create the socket + "/run/kanidm-unixd:/var/run/kanidm-unixd" + ]; + # Needs to connect to kanidmd + PrivateNetwork = false; + RestrictAddressFamilies = [ "AF_INET" "AF_INET6" "AF_UNIX" ]; + TemporaryFileSystem = "/:ro"; + }; + environment.RUST_LOG = "info"; + }; + + systemd.services.kanidm-unixd-tasks = lib.mkIf cfg.enablePam { + description = "Kanidm PAM home management daemon"; + wantedBy = [ "multi-user.target" ]; + after = [ "network.target" "kanidm-unixd.service" ]; + partOf = [ "kanidm-unixd.service" ]; + restartTriggers = [ unixConfigFile clientConfigFile ]; + serviceConfig = { + ExecStart = "${pkgs.kanidm}/bin/kanidm_unixd_tasks"; + + BindReadOnlyPaths = [ + "/nix/store" + "-/etc/resolv.conf" + "-/etc/nsswitch.conf" + "-/etc/hosts" + "-/etc/localtime" + "-/etc/kanidm" + "-/etc/static/kanidm" + ]; + BindPaths = [ + # To manage home directories + "/home" + # To connect to kanidm-unixd + "/run/kanidm-unixd:/var/run/kanidm-unixd" + ]; + # CAP_DAC_OVERRIDE is needed to ignore ownership of unixd socket + CapabilityBoundingSet = [ "CAP_CHOWN" "CAP_FOWNER" "CAP_DAC_OVERRIDE" "CAP_DAC_READ_SEARCH" ]; + IPAddressDeny = "any"; + # Need access to users + PrivateUsers = false; + # Need access to home directories + ProtectHome = false; + RestrictAddressFamilies = [ "AF_UNIX" ]; + TemporaryFileSystem = "/:ro"; + }; + environment.RUST_LOG = "info"; + }; + + # These paths are hardcoded + environment.etc = lib.mkMerge [ + (lib.mkIf options.services.kanidm.clientSettings.isDefined { + "kanidm/config".source = clientConfigFile; + }) + (lib.mkIf cfg.enablePam { + "kanidm/unixd".source = unixConfigFile; + }) + ]; + + system.nssModules = lib.mkIf cfg.enablePam [ pkgs.kanidm ]; + + system.nssDatabases.group = lib.optional cfg.enablePam "kanidm"; + system.nssDatabases.passwd = lib.optional cfg.enablePam "kanidm"; + + users.groups = lib.mkMerge [ + (lib.mkIf cfg.enableServer { + kanidm = { }; + }) + (lib.mkIf cfg.enablePam { + kanidm-unixd = { }; + }) + ]; + users.users = lib.mkMerge [ + (lib.mkIf cfg.enableServer { + kanidm = { + description = "Kanidm server"; + isSystemUser = true; + group = "kanidm"; + packages = with pkgs; [ kanidm ]; + }; + }) + (lib.mkIf cfg.enablePam { + kanidm-unixd = { + description = "Kanidm PAM daemon"; + isSystemUser = true; + group = "kanidm-unixd"; + }; + }) + ]; + }; + + meta.maintainers = with lib.maintainers; [ erictapen Flakebi ]; + meta.buildDocsInSandbox = false; +} |