nixpkgs/nixos/modules/config/ldap.nix
Eelco Dolstra 29027fd1e1 Rewrite ‘with pkgs.lib’ -> ‘with lib’
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
2014-04-14 16:26:48 +02:00

247 lines
7.4 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
with pkgs;
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
tls_checkpeer no
''}
${optionalString (config.users.ldap.bind.distinguishedName != "") ''
binddn ${config.users.ldap.bind.distinguishedName}
''}
${optionalString (cfg.extraConfig != "") cfg.extraConfig }
'';
};
nslcdConfig = {
target = "nslcd.conf";
source = writeText "nslcd.conf" ''
uid nslcd
gid nslcd
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.extraConfig != "") cfg.daemon.extraConfig }
'';
};
insertLdapPassword = !config.users.ldap.daemon.enable &&
config.users.ldap.bind.distinguishedName != "";
in
{
###### interface
options = {
users.ldap = {
enable = mkOption {
default = false;
description = "Whether to enable authentication against an LDAP server.";
};
server = mkOption {
example = "ldap://ldap.example.org/";
description = "The URL of the LDAP server.";
};
base = mkOption {
example = "dc=example,dc=org";
description = "The distinguished name of the search base.";
};
useTLS = mkOption {
default = false;
description = ''
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</option> or to forego
security.
'';
};
timeLimit = mkOption {
default = 0;
type = types.int;
description = ''
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 {
default = false;
description = ''
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.string;
description = ''
Extra configuration options that will be added verbatim at
the end of the nslcd configuration file (nslcd.conf).
'' ;
} ;
};
bind = {
distinguishedName = mkOption {
default = "";
example = "cn=admin,dc=example,dc=com";
type = types.string;
description = ''
The distinguished name to bind to the LDAP server with. If this
is not specified, an anonymous bind will be done.
'';
};
password = mkOption {
default = "/etc/ldap/bind.password";
type = types.string;
description = ''
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 = ''
Specifies the time limit (in seconds) to use when connecting
to the directory server. This is distinct from the time limit
specified in <literal>users.ldap.timeLimit</literal> and affects
the initial server connection only.
'';
};
policy = mkOption {
default = "hard_open";
type = types.string;
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
<literal>nss_ldap</literal> will return immediately on server
failure. All hard reconnect policies block with exponential
backoff before retrying.
'';
};
};
extraConfig = mkOption {
default = "";
type = types.string;
description = ''
Extra configuration options that will be added verbatim at
the end of the ldap configuration file (ldap.conf).
If <literal>users.ldap.daemon</literal> is enabled, this
configuration will not be used. In that case, use
<literal>users.ldap.daemon.extraConfig</literal> instead.
'' ;
};
};
};
###### implementation
config = mkIf cfg.enable {
environment.etc = if cfg.daemon.enable then [nslcdConfig] else [ldapConfig];
system.activationScripts = mkIf insertLdapPassword {
ldap = stringAfter [ "etc" "groups" "users" ] ''
if test -f "${cfg.bind.password}" ; then
echo "bindpw "$(cat ${cfg.bind.password})"" | cat ${ldapConfig} - > /etc/ldap.conf.bindpw
mv -fT /etc/ldap.conf.bindpw /etc/ldap.conf
chmod 600 /etc/ldap.conf
fi
'';
};
system.nssModules = singleton (
if cfg.daemon.enable then nss_pam_ldapd else nss_ldap
);
users = mkIf cfg.daemon.enable {
extraGroups.nslcd = {
gid = config.ids.gids.nslcd;
};
extraUsers.nslcd = {
uid = config.ids.uids.nslcd;
description = "nslcd user.";
group = "nslcd";
};
};
systemd.services = mkIf cfg.daemon.enable {
nslcd = {
wantedBy = [ "nss-user-lookup.target" ];
before = [ "nss-user-lookup.target" ];
after = [ "network.target" ];
preStart = ''
mkdir -p /run/nslcd
rm -f /run/nslcd/nslcd.pid;
chown nslcd.nslcd /run/nslcd
${optionalString (cfg.bind.distinguishedName != "") ''
if test -s "${cfg.bind.password}" ; then
ln -sfT "${cfg.bind.password}" /run/nslcd/bindpw
fi
''}
'';
serviceConfig = {
ExecStart = "${nss_pam_ldapd}/sbin/nslcd";
Type = "forking";
PIDFile = "/run/nslcd/nslcd.pid";
Restart = "always";
};
};
};
};
}