nixpkgs-suyu/nixos/modules/config/ldap.nix
pennae 2e751c0772 treewide: automatically md-convert option descriptions
the conversion procedure is simple:

 - find all things that look like options, ie calls to either `mkOption`
   or `lib.mkOption` that take an attrset. remember the attrset as the
   option
 - for all options, find a `description` attribute who's value is not a
   call to `mdDoc` or `lib.mdDoc`
 - textually convert the entire value of the attribute to MD with a few
   simple regexes (the set from mdize-module.sh)
 - if the change produced a change in the manual output, discard
 - if the change kept the manual unchanged, add some text to the
   description to make sure we've actually found an option. if the
   manual changes this time, keep the converted description

this procedure converts 80% of nixos options to markdown. around 2000
options remain to be inspected, but most of those fail the "does not
change the manual output check": currently the MD conversion process
does not faithfully convert docbook tags like <code> and <package>, so
any option using such tags will not be converted at all.
2022-07-30 15:16:34 +02:00

303 lines
9.7 KiB
Nix

{ config, lib, pkgs, ... }:
with pkgs;
with lib;
let
cfg = config.users.ldap;
# Careful: OpenLDAP seems to be very picky about the indentation of
# this file. Directives HAVE to start in the first column!
ldapConfig = {
target = "ldap.conf";
source = writeText "ldap.conf" ''
uri ${config.users.ldap.server}
base ${config.users.ldap.base}
timelimit ${toString config.users.ldap.timeLimit}
bind_timelimit ${toString config.users.ldap.bind.timeLimit}
bind_policy ${config.users.ldap.bind.policy}
${optionalString config.users.ldap.useTLS ''
ssl start_tls
''}
${optionalString (config.users.ldap.bind.distinguishedName != "") ''
binddn ${config.users.ldap.bind.distinguishedName}
''}
${optionalString (cfg.extraConfig != "") cfg.extraConfig }
'';
};
nslcdConfig = writeText "nslcd.conf" ''
uri ${cfg.server}
base ${cfg.base}
timelimit ${toString cfg.timeLimit}
bind_timelimit ${toString cfg.bind.timeLimit}
${optionalString (cfg.bind.distinguishedName != "")
"binddn ${cfg.bind.distinguishedName}" }
${optionalString (cfg.daemon.rootpwmoddn != "")
"rootpwmoddn ${cfg.daemon.rootpwmoddn}" }
${optionalString (cfg.daemon.extraConfig != "") cfg.daemon.extraConfig }
'';
# nslcd normally reads configuration from /etc/nslcd.conf.
# this file might contain secrets. We append those at runtime,
# so redirect its location to something more temporary.
nslcdWrapped = runCommand "nslcd-wrapped" { nativeBuildInputs = [ makeWrapper ]; } ''
mkdir -p $out/bin
makeWrapper ${nss_pam_ldapd}/sbin/nslcd $out/bin/nslcd \
--set LD_PRELOAD "${pkgs.libredirect}/lib/libredirect.so" \
--set NIX_REDIRECTS "/etc/nslcd.conf=/run/nslcd/nslcd.conf"
'';
in
{
###### interface
options = {
users.ldap = {
enable = mkEnableOption "authentication against an LDAP server";
loginPam = mkOption {
type = types.bool;
default = true;
description = lib.mdDoc "Whether to include authentication against LDAP in login PAM.";
};
nsswitch = mkOption {
type = types.bool;
default = true;
description = lib.mdDoc "Whether to include lookup against LDAP in NSS.";
};
server = mkOption {
type = types.str;
example = "ldap://ldap.example.org/";
description = lib.mdDoc "The URL of the LDAP server.";
};
base = mkOption {
type = types.str;
example = "dc=example,dc=org";
description = lib.mdDoc "The distinguished name of the search base.";
};
useTLS = mkOption {
type = types.bool;
default = false;
description = lib.mdDoc ''
If enabled, use TLS (encryption) over an LDAP (port 389)
connection. The alternative is to specify an LDAPS server (port
636) in {option}`users.ldap.server` or to forego
security.
'';
};
timeLimit = mkOption {
default = 0;
type = types.int;
description = lib.mdDoc ''
Specifies the time limit (in seconds) to use when performing
searches. A value of zero (0), which is the default, is to
wait indefinitely for searches to be completed.
'';
};
daemon = {
enable = mkOption {
type = types.bool;
default = false;
description = lib.mdDoc ''
Whether to let the nslcd daemon (nss-pam-ldapd) handle the
LDAP lookups for NSS and PAM. This can improve performance,
and if you need to bind to the LDAP server with a password,
it increases security, since only the nslcd user needs to
have access to the bindpw file, not everyone that uses NSS
and/or PAM. If this option is enabled, a local nscd user is
created automatically, and the nslcd service is started
automatically when the network get up.
'';
};
extraConfig = mkOption {
default = "";
type = types.lines;
description = lib.mdDoc ''
Extra configuration options that will be added verbatim at
the end of the nslcd configuration file (`nslcd.conf(5)`).
'' ;
} ;
rootpwmoddn = mkOption {
default = "";
example = "cn=admin,dc=example,dc=com";
type = types.str;
description = lib.mdDoc ''
The distinguished name to use to bind to the LDAP server
when the root user tries to modify a user's password.
'';
};
rootpwmodpwFile = mkOption {
default = "";
example = "/run/keys/nslcd.rootpwmodpw";
type = types.str;
description = lib.mdDoc ''
The path to a file containing the credentials with which to bind to
the LDAP server if the root user tries to change a user's password.
'';
};
};
bind = {
distinguishedName = mkOption {
default = "";
example = "cn=admin,dc=example,dc=com";
type = types.str;
description = lib.mdDoc ''
The distinguished name to bind to the LDAP server with. If this
is not specified, an anonymous bind will be done.
'';
};
passwordFile = mkOption {
default = "/etc/ldap/bind.password";
type = types.str;
description = lib.mdDoc ''
The path to a file containing the credentials to use when binding
to the LDAP server (if not binding anonymously).
'';
};
timeLimit = mkOption {
default = 30;
type = types.int;
description = lib.mdDoc ''
Specifies the time limit (in seconds) to use when connecting
to the directory server. This is distinct from the time limit
specified in {option}`users.ldap.timeLimit` and affects
the initial server connection only.
'';
};
policy = mkOption {
default = "hard_open";
type = types.enum [ "hard_open" "hard_init" "soft" ];
description = ''
Specifies the policy to use for reconnecting to an unavailable
LDAP server. The default is <literal>hard_open</literal>, which
reconnects if opening the connection to the directory server
failed. By contrast, <literal>hard_init</literal> reconnects if
initializing the connection failed. Initializing may not
actually contact the directory server, and it is possible that
a malformed configuration file will trigger reconnection. If
<literal>soft</literal> is specified, then
<package>nss_ldap</package> will return immediately on server
failure. All hard reconnect policies block with exponential
backoff before retrying.
'';
};
};
extraConfig = mkOption {
default = "";
type = types.lines;
description = lib.mdDoc ''
Extra configuration options that will be added verbatim at
the end of the ldap configuration file (`ldap.conf(5)`).
If {option}`users.ldap.daemon` is enabled, this
configuration will not be used. In that case, use
{option}`users.ldap.daemon.extraConfig` instead.
'' ;
};
};
};
###### implementation
config = mkIf cfg.enable {
environment.etc = optionalAttrs (!cfg.daemon.enable) {
"ldap.conf" = ldapConfig;
};
system.activationScripts = mkIf (!cfg.daemon.enable) {
ldap = stringAfter [ "etc" "groups" "users" ] ''
if test -f "${cfg.bind.passwordFile}" ; then
umask 0077
conf="$(mktemp)"
printf 'bindpw %s\n' "$(cat ${cfg.bind.passwordFile})" |
cat ${ldapConfig.source} - >"$conf"
mv -fT "$conf" /etc/ldap.conf
fi
'';
};
system.nssModules = mkIf cfg.nsswitch (singleton (
if cfg.daemon.enable then nss_pam_ldapd else nss_ldap
));
system.nssDatabases.group = optional cfg.nsswitch "ldap";
system.nssDatabases.passwd = optional cfg.nsswitch "ldap";
system.nssDatabases.shadow = optional cfg.nsswitch "ldap";
users = mkIf cfg.daemon.enable {
groups.nslcd = {
gid = config.ids.gids.nslcd;
};
users.nslcd = {
uid = config.ids.uids.nslcd;
description = "nslcd user.";
group = "nslcd";
};
};
systemd.services = mkIf cfg.daemon.enable {
nslcd = {
wantedBy = [ "multi-user.target" ];
preStart = ''
umask 0077
conf="$(mktemp)"
{
cat ${nslcdConfig}
test -z '${cfg.bind.distinguishedName}' -o ! -f '${cfg.bind.passwordFile}' ||
printf 'bindpw %s\n' "$(cat '${cfg.bind.passwordFile}')"
test -z '${cfg.daemon.rootpwmoddn}' -o ! -f '${cfg.daemon.rootpwmodpwFile}' ||
printf 'rootpwmodpw %s\n' "$(cat '${cfg.daemon.rootpwmodpwFile}')"
} >"$conf"
mv -fT "$conf" /run/nslcd/nslcd.conf
'';
restartTriggers = [
nslcdConfig
cfg.bind.passwordFile
cfg.daemon.rootpwmodpwFile
];
serviceConfig = {
ExecStart = "${nslcdWrapped}/bin/nslcd";
Type = "forking";
Restart = "always";
User = "nslcd";
Group = "nslcd";
RuntimeDirectory = [ "nslcd" ];
PIDFile = "/run/nslcd/nslcd.pid";
AmbientCapabilities = "CAP_SYS_RESOURCE";
};
};
};
};
imports =
[ (mkRenamedOptionModule [ "users" "ldap" "bind" "password"] [ "users" "ldap" "bind" "passwordFile"])
];
}