{pkgs, config, ...}:
with pkgs.lib;
let
ids = config.ids;
users = config.users;
userOpts = { name, config, ... }: {
options = {
name = mkOption {
type = with types; uniq string;
description = "The name of the user account. If undefined, the name of the attribute set will be used.";
};
description = mkOption {
type = with types; uniq string;
default = "";
description = "A short description of the user account.";
};
uid = mkOption {
type = with types; uniq (nullOr int);
default = null;
description = "The account UID. If undefined, NixOS will select a free UID.";
};
group = mkOption {
type = with types; uniq string;
default = "nogroup";
description = "The user's primary group.";
};
extraGroups = mkOption {
type = types.listOf types.string;
default = [];
description = "The user's auxiliary groups.";
};
home = mkOption {
type = with types; uniq string;
default = "/var/empty";
description = "The user's home directory.";
};
shell = mkOption {
type = with types; uniq string;
default = "/var/run/current-system/sw/sbin/nologin";
description = "The path to the user's shell.";
};
createHome = mkOption {
type = types.bool;
default = false;
description = "If true, the home directory will be created automatically.";
};
useDefaultShell = mkOption {
type = types.bool;
default = false;
description = "If true, the user's shell will be set to <literal>users.defaultUserShell</literal>.";
};
password = mkOption {
type = with types; uniq (nullOr string);
default = null;
description = "The user's password. If undefined, no password is set for the user. Warning: do not set confidential information here because this data would be readable by all. This option should only be used for public account such as guest.";
};
isSystemUser = mkOption {
type = types.bool;
default = true;
description = "Indicates if the user is a system user or not.";
};
createUser = mkOption {
type = types.bool;
default = true;
description = "
Indicates if the user should be created automatically as a local user.
Set this to false if the user for instance is an LDAP user. NixOS will
then not modify any of the basic properties for the user account.
";
};
};
config = {
name = mkDefault name;
uid = mkDefault (attrByPath [name] null ids.uids);
shell = mkIf config.useDefaultShell (mkDefault users.defaultUserShell);
};
};
groupOpts = { name, config, ... }: {
options = {
name = mkOption {
type = with types; uniq string;
description = "The name of the group. If undefined, the name of the attribute set will be used.";
};
gid = mkOption {
type = with types; uniq (nullOr int);
default = null;
description = "The GID of the group. If undefined, NixOS will select a free GID.";
};
};
config = {
name = mkDefault name;
gid = mkDefault (attrByPath [name] null ids.gids);
};
};
# Note: the 'X' in front of the password is to distinguish between
# having an empty password, and not having a password.
serializedUser = userName: let u = getAttr userName config.users.extraUsers; in "${u.name}\n${u.description}\n${if u.uid != null then toString u.uid else ""}\n${u.group}\n${toString (concatStringsSep "," u.extraGroups)}\n${u.home}\n${u.shell}\n${toString u.createHome}\n${if u.password != null then "X" + u.password else ""}\n${toString u.isSystemUser}\n${if u.createUser then "yes" else "no"}\n";
# keep this extra file so that cat can be used to pass special chars such as "`" which is used in the avahi daemon
usersFile = pkgs.writeText "users" (
concatMapStrings serializedUser (attrNames config.users.extraUsers)
);
in
{
###### interface
options = {
users.extraUsers = mkOption {
default = {};
type = types.loaOf types.optionSet;
example = {
alice = {
uid = 1234;
description = "Alice";
home = "/home/alice";
createHome = true;
group = "users";
extraGroups = ["wheel"];
shell = "/bin/sh";
password = "foobar";
};
};
description = ''
Additional user accounts to be created automatically by the system.
'';
options = [ userOpts ];
};
users.extraGroups = mkOption {
default = {};
example =
{ students.gid = 1001;
hackers = { };
};
type = types.loaOf types.optionSet;
description = ''
Additional groups to be created automatically by the system.
'';
options = [ groupOpts ];
};
};
###### implementation
config = {
users.extraUsers = {
root = {
description = "System administrator";
home = "/root";
shell = config.users.defaultUserShell;
group = "root";
};
nobody = {
description = "Unprivileged account (don't use!)";
};
};
users.extraGroups = {
root = { };
wheel = { };
disk = { };
kmem = { };
tty = { };
floppy = { };
uucp = { };
lp = { };
cdrom = { };
tape = { };
audio = { };
video = { };
dialout = { };
nogroup = { };
users = { };
nixbld = { };
utmp = { };
};
system.activationScripts.rootPasswd = stringAfter [ "etc" ]
''
# If there is no password file yet, create a root account with an
# empty password.
if ! test -e /etc/passwd; then
rootHome=/root
touch /etc/passwd; chmod 0644 /etc/passwd
touch /etc/group; chmod 0644 /etc/group
touch /etc/shadow; chmod 0600 /etc/shadow
# Can't use useradd, since it complains that it doesn't know us
# (bootstrap problem!).
echo "root:x:0:0:System administrator:$rootHome:${config.users.defaultUserShell}" >> /etc/passwd
echo "root::::::::" >> /etc/shadow
fi
'';
system.activationScripts.users = stringAfter [ "groups" ]
''
echo "updating users..."
cat ${usersFile} | while true; do
read name || break
read description
read uid
read group
read extraGroups
read home
read shell
read createHome
read password
read isSystemUser
read createUser
if ! test "$createUser" = "yes"; then
continue
fi
if ! curEnt=$(getent passwd "$name"); then
useradd ''${isSystemUser:+--system} \
--comment "$description" \
''${uid:+--uid $uid} \
--gid "$group" \
--groups "$extraGroups" \
--home "$home" \
--shell "$shell" \
''${createHome:+--create-home} \
"$name"
if test "''${password:0:1}" = 'X'; then
(echo "''${password:1}"; echo "''${password:1}") | ${pkgs.shadow}/bin/passwd "$name"
fi
else
#echo "updating user $name..."
oldIFS="$IFS"; IFS=:; set -- $curEnt; IFS="$oldIFS"
prevUid=$3
prevHome=$6
# Don't change the UID if it's the same, otherwise usermod
# will complain.
if test "$prevUid" = "$uid"; then unset uid; fi
# Don't change the home directory if it's the same to prevent
# unnecessary warnings about logged in users.
if test "$prevHome" = "$home"; then unset home; fi
usermod \
--comment "$description" \
''${uid:+--uid $uid} \
--gid "$group" \
--groups "$extraGroups" \
''${home:+--home "$home"} \
--shell "$shell" \
"$name"
fi
done
'';
system.activationScripts.groups = stringAfter [ "rootPasswd" "binsh" "etc" "var" ]
''
echo "updating groups..."
createGroup() {
name="$1"
gid="$2"
if ! curEnt=$(getent group "$name"); then
groupadd --system \
''${gid:+--gid $gid} \
"$name"
else
#echo "updating group $name..."
oldIFS="$IFS"; IFS=:; set -- $curEnt; IFS="$oldIFS"
prevGid=$3
if test -n "$gid" -a "$prevGid" != "$gid"; then
groupmod --gid $gid "$name"
fi
fi
}
${flip concatMapStrings (attrValues config.users.extraGroups) (g: ''
createGroup '${g.name}' '${toString g.gid}'
'')}
'';
};
}