659 lines
22 KiB
Nix
659 lines
22 KiB
Nix
{ config, lib, utils, pkgs, ... }:
|
||
|
||
with lib;
|
||
|
||
let
|
||
ids = config.ids;
|
||
cfg = config.users;
|
||
|
||
# Check whether a password hash will allow login.
|
||
allowsLogin = hash:
|
||
hash == "" # login without password
|
||
|| !(lib.elem hash
|
||
[ null # password login disabled
|
||
"!" # password login disabled
|
||
"!!" # a variant of "!"
|
||
"*" # password unset
|
||
]);
|
||
|
||
passwordDescription = ''
|
||
The options <option>hashedPassword</option>,
|
||
<option>password</option> and <option>passwordFile</option>
|
||
controls what password is set for the user.
|
||
<option>hashedPassword</option> overrides both
|
||
<option>password</option> and <option>passwordFile</option>.
|
||
<option>password</option> overrides <option>passwordFile</option>.
|
||
If none of these three options are set, no password is assigned to
|
||
the user, and the user will not be able to do password logins.
|
||
If the option <option>users.mutableUsers</option> is true, the
|
||
password defined in one of the three options will only be set when
|
||
the user is created for the first time. After that, you are free to
|
||
change the password with the ordinary user management commands. If
|
||
<option>users.mutableUsers</option> is false, you cannot change
|
||
user passwords, they will always be set according to the password
|
||
options.
|
||
'';
|
||
|
||
hashedPasswordDescription = ''
|
||
To generate a hashed password run <literal>mkpasswd -m sha-512</literal>.
|
||
|
||
If set to an empty string (<literal>""</literal>), this user will
|
||
be able to log in without being asked for a password (but not via remote
|
||
services such as SSH, or indirectly via <command>su</command> or
|
||
<command>sudo</command>). This should only be used for e.g. bootable
|
||
live systems. Note: this is different from setting an empty password,
|
||
which ca be achieved using <option>users.users.<name?>.password</option>.
|
||
|
||
If set to <literal>null</literal> (default) this user will not
|
||
be able to log in using a password (i.e. via <command>login</command>
|
||
command).
|
||
'';
|
||
|
||
userOpts = { name, config, ... }: {
|
||
|
||
options = {
|
||
|
||
name = mkOption {
|
||
type = types.str;
|
||
apply = x: assert (builtins.stringLength x < 32 || abort "Username '${x}' is longer than 31 characters which is not allowed!"); x;
|
||
description = ''
|
||
The name of the user account. If undefined, the name of the
|
||
attribute set will be used.
|
||
'';
|
||
};
|
||
|
||
description = mkOption {
|
||
type = types.str;
|
||
default = "";
|
||
example = "Alice Q. User";
|
||
description = ''
|
||
A short description of the user account, typically the
|
||
user's full name. This is actually the “GECOS” or “comment”
|
||
field in <filename>/etc/passwd</filename>.
|
||
'';
|
||
};
|
||
|
||
uid = mkOption {
|
||
type = with types; nullOr int;
|
||
default = null;
|
||
description = ''
|
||
The account UID. If the UID is null, a free UID is picked on
|
||
activation.
|
||
'';
|
||
};
|
||
|
||
isSystemUser = mkOption {
|
||
type = types.bool;
|
||
default = false;
|
||
description = ''
|
||
Indicates if the user is a system user or not. This option
|
||
only has an effect if <option>uid</option> is
|
||
<option>null</option>, in which case it determines whether
|
||
the user's UID is allocated in the range for system users
|
||
(below 500) or in the range for normal users (starting at
|
||
1000).
|
||
'';
|
||
};
|
||
|
||
isNormalUser = mkOption {
|
||
type = types.bool;
|
||
default = false;
|
||
description = ''
|
||
Indicates whether this is an account for a “real” user. This
|
||
automatically sets <option>group</option> to
|
||
<literal>users</literal>, <option>createHome</option> to
|
||
<literal>true</literal>, <option>home</option> to
|
||
<filename>/home/<replaceable>username</replaceable></filename>,
|
||
<option>useDefaultShell</option> to <literal>true</literal>,
|
||
and <option>isSystemUser</option> to
|
||
<literal>false</literal>.
|
||
'';
|
||
};
|
||
|
||
group = mkOption {
|
||
type = types.str;
|
||
apply = x: assert (builtins.stringLength x < 32 || abort "Group name '${x}' is longer than 31 characters which is not allowed!"); x;
|
||
default = "nogroup";
|
||
description = "The user's primary group.";
|
||
};
|
||
|
||
extraGroups = mkOption {
|
||
type = types.listOf types.str;
|
||
default = [];
|
||
description = "The user's auxiliary groups.";
|
||
};
|
||
|
||
home = mkOption {
|
||
type = types.path;
|
||
default = "/var/empty";
|
||
description = "The user's home directory.";
|
||
};
|
||
|
||
cryptHomeLuks = mkOption {
|
||
type = with types; nullOr str;
|
||
default = null;
|
||
description = ''
|
||
Path to encrypted luks device that contains
|
||
the user's home directory.
|
||
'';
|
||
};
|
||
|
||
pamMount = mkOption {
|
||
type = with types; attrsOf str;
|
||
default = {};
|
||
description = ''
|
||
Attributes for user's entry in
|
||
<filename>pam_mount.conf.xml</filename>.
|
||
Useful attributes might include <code>path</code>,
|
||
<code>options</code>, <code>fstype</code>, and <code>server</code>.
|
||
See <link
|
||
xlink:href="http://pam-mount.sourceforge.net/pam_mount.conf.5.html" />
|
||
for more information.
|
||
'';
|
||
};
|
||
|
||
shell = mkOption {
|
||
type = types.nullOr (types.either types.shellPackage types.path);
|
||
default = pkgs.shadow;
|
||
defaultText = "pkgs.shadow";
|
||
example = literalExample "pkgs.bashInteractive";
|
||
description = ''
|
||
The path to the user's shell. Can use shell derivations,
|
||
like <literal>pkgs.bashInteractive</literal>. Don’t
|
||
forget to enable your shell in
|
||
<literal>programs</literal> if necessary,
|
||
like <code>programs.zsh.enable = true;</code>.
|
||
'';
|
||
};
|
||
|
||
subUidRanges = mkOption {
|
||
type = with types; listOf (submodule subordinateUidRange);
|
||
default = [];
|
||
example = [
|
||
{ startUid = 1000; count = 1; }
|
||
{ startUid = 100001; count = 65534; }
|
||
];
|
||
description = ''
|
||
Subordinate user ids that user is allowed to use.
|
||
They are set into <filename>/etc/subuid</filename> and are used
|
||
by <literal>newuidmap</literal> for user namespaces.
|
||
'';
|
||
};
|
||
|
||
subGidRanges = mkOption {
|
||
type = with types; listOf (submodule subordinateGidRange);
|
||
default = [];
|
||
example = [
|
||
{ startGid = 100; count = 1; }
|
||
{ startGid = 1001; count = 999; }
|
||
];
|
||
description = ''
|
||
Subordinate group ids that user is allowed to use.
|
||
They are set into <filename>/etc/subgid</filename> and are used
|
||
by <literal>newgidmap</literal> for user namespaces.
|
||
'';
|
||
};
|
||
|
||
createHome = mkOption {
|
||
type = types.bool;
|
||
default = false;
|
||
description = ''
|
||
Whether to create the home directory and ensure ownership as well as
|
||
permissions to match the user.
|
||
'';
|
||
};
|
||
|
||
useDefaultShell = mkOption {
|
||
type = types.bool;
|
||
default = false;
|
||
description = ''
|
||
If true, the user's shell will be set to
|
||
<option>users.defaultUserShell</option>.
|
||
'';
|
||
};
|
||
|
||
hashedPassword = mkOption {
|
||
type = with types; nullOr str;
|
||
default = null;
|
||
description = ''
|
||
Specifies the hashed password for the user.
|
||
${passwordDescription}
|
||
${hashedPasswordDescription}
|
||
'';
|
||
};
|
||
|
||
password = mkOption {
|
||
type = with types; nullOr str;
|
||
default = null;
|
||
description = ''
|
||
Specifies the (clear text) password for the user.
|
||
Warning: do not set confidential information here
|
||
because it is world-readable in the Nix store. This option
|
||
should only be used for public accounts.
|
||
${passwordDescription}
|
||
'';
|
||
};
|
||
|
||
passwordFile = mkOption {
|
||
type = with types; nullOr str;
|
||
default = null;
|
||
description = ''
|
||
The full path to a file that contains the user's password. The password
|
||
file is read on each system activation. The file should contain
|
||
exactly one line, which should be the password in an encrypted form
|
||
that is suitable for the <literal>chpasswd -e</literal> command.
|
||
${passwordDescription}
|
||
'';
|
||
};
|
||
|
||
initialHashedPassword = mkOption {
|
||
type = with types; nullOr str;
|
||
default = null;
|
||
description = ''
|
||
Specifies the initial hashed password for the user, i.e. the
|
||
hashed password assigned if the user does not already
|
||
exist. If <option>users.mutableUsers</option> is true, the
|
||
password can be changed subsequently using the
|
||
<command>passwd</command> command. Otherwise, it's
|
||
equivalent to setting the <option>hashedPassword</option> option.
|
||
|
||
${hashedPasswordDescription}
|
||
'';
|
||
};
|
||
|
||
initialPassword = mkOption {
|
||
type = with types; nullOr str;
|
||
default = null;
|
||
description = ''
|
||
Specifies the initial password for the user, i.e. the
|
||
password assigned if the user does not already exist. If
|
||
<option>users.mutableUsers</option> is true, the password
|
||
can be changed subsequently using the
|
||
<command>passwd</command> command. Otherwise, it's
|
||
equivalent to setting the <option>password</option>
|
||
option. The same caveat applies: the password specified here
|
||
is world-readable in the Nix store, so it should only be
|
||
used for guest accounts or passwords that will be changed
|
||
promptly.
|
||
'';
|
||
};
|
||
|
||
packages = mkOption {
|
||
type = types.listOf types.package;
|
||
default = [];
|
||
example = literalExample "[ pkgs.firefox pkgs.thunderbird ]";
|
||
description = ''
|
||
The set of packages that should be made available to the user.
|
||
This is in contrast to <option>environment.systemPackages</option>,
|
||
which adds packages to all users.
|
||
'';
|
||
};
|
||
|
||
};
|
||
|
||
config = mkMerge
|
||
[ { name = mkDefault name;
|
||
shell = mkIf config.useDefaultShell (mkDefault cfg.defaultUserShell);
|
||
}
|
||
(mkIf config.isNormalUser {
|
||
group = mkDefault "users";
|
||
createHome = mkDefault true;
|
||
home = mkDefault "/home/${config.name}";
|
||
useDefaultShell = mkDefault true;
|
||
isSystemUser = mkDefault false;
|
||
})
|
||
# If !mutableUsers, setting ‘initialPassword’ is equivalent to
|
||
# setting ‘password’ (and similarly for hashed passwords).
|
||
(mkIf (!cfg.mutableUsers && config.initialPassword != null) {
|
||
password = mkDefault config.initialPassword;
|
||
})
|
||
(mkIf (!cfg.mutableUsers && config.initialHashedPassword != null) {
|
||
hashedPassword = mkDefault config.initialHashedPassword;
|
||
})
|
||
];
|
||
|
||
};
|
||
|
||
groupOpts = { name, ... }: {
|
||
|
||
options = {
|
||
|
||
name = mkOption {
|
||
type = types.str;
|
||
description = ''
|
||
The name of the group. If undefined, the name of the attribute set
|
||
will be used.
|
||
'';
|
||
};
|
||
|
||
gid = mkOption {
|
||
type = with types; nullOr int;
|
||
default = null;
|
||
description = ''
|
||
The group GID. If the GID is null, a free GID is picked on
|
||
activation.
|
||
'';
|
||
};
|
||
|
||
members = mkOption {
|
||
type = with types; listOf str;
|
||
default = [];
|
||
description = ''
|
||
The user names of the group members, added to the
|
||
<literal>/etc/group</literal> file.
|
||
'';
|
||
};
|
||
|
||
};
|
||
|
||
config = {
|
||
name = mkDefault name;
|
||
};
|
||
|
||
};
|
||
|
||
subordinateUidRange = {
|
||
options = {
|
||
startUid = mkOption {
|
||
type = types.int;
|
||
description = ''
|
||
Start of the range of subordinate user ids that user is
|
||
allowed to use.
|
||
'';
|
||
};
|
||
count = mkOption {
|
||
type = types.int;
|
||
default = 1;
|
||
description = "Count of subordinate user ids";
|
||
};
|
||
};
|
||
};
|
||
|
||
subordinateGidRange = {
|
||
options = {
|
||
startGid = mkOption {
|
||
type = types.int;
|
||
description = ''
|
||
Start of the range of subordinate group ids that user is
|
||
allowed to use.
|
||
'';
|
||
};
|
||
count = mkOption {
|
||
type = types.int;
|
||
default = 1;
|
||
description = "Count of subordinate group ids";
|
||
};
|
||
};
|
||
};
|
||
|
||
idsAreUnique = set: idAttr: !(fold (name: args@{ dup, acc }:
|
||
let
|
||
id = builtins.toString (builtins.getAttr idAttr (builtins.getAttr name set));
|
||
exists = builtins.hasAttr id acc;
|
||
newAcc = acc // (builtins.listToAttrs [ { name = id; value = true; } ]);
|
||
in if dup then args else if exists
|
||
then builtins.trace "Duplicate ${idAttr} ${id}" { dup = true; acc = null; }
|
||
else { dup = false; acc = newAcc; }
|
||
) { dup = false; acc = {}; } (builtins.attrNames set)).dup;
|
||
|
||
uidsAreUnique = idsAreUnique (filterAttrs (n: u: u.uid != null) cfg.users) "uid";
|
||
gidsAreUnique = idsAreUnique (filterAttrs (n: g: g.gid != null) cfg.groups) "gid";
|
||
|
||
spec = pkgs.writeText "users-groups.json" (builtins.toJSON {
|
||
inherit (cfg) mutableUsers;
|
||
users = mapAttrsToList (_: u:
|
||
{ inherit (u)
|
||
name uid group description home createHome isSystemUser
|
||
password passwordFile hashedPassword
|
||
isNormalUser subUidRanges subGidRanges
|
||
initialPassword initialHashedPassword;
|
||
shell = utils.toShellPath u.shell;
|
||
}) cfg.users;
|
||
groups = mapAttrsToList (n: g:
|
||
{ inherit (g) name gid;
|
||
members = g.members ++ (mapAttrsToList (n: u: u.name) (
|
||
filterAttrs (n: u: elem g.name u.extraGroups) cfg.users
|
||
));
|
||
}) cfg.groups;
|
||
});
|
||
|
||
systemShells =
|
||
let
|
||
shells = mapAttrsToList (_: u: u.shell) cfg.users;
|
||
in
|
||
filter types.shellPackage.check shells;
|
||
|
||
in {
|
||
imports = [
|
||
(mkAliasOptionModule [ "users" "extraUsers" ] [ "users" "users" ])
|
||
(mkAliasOptionModule [ "users" "extraGroups" ] [ "users" "groups" ])
|
||
(mkChangedOptionModule
|
||
[ "security" "initialRootPassword" ]
|
||
[ "users" "users" "root" "initialHashedPassword" ]
|
||
(cfg: if cfg.security.initialRootPassword == "!"
|
||
then null
|
||
else cfg.security.initialRootPassword))
|
||
];
|
||
|
||
###### interface
|
||
|
||
options = {
|
||
|
||
users.mutableUsers = mkOption {
|
||
type = types.bool;
|
||
default = true;
|
||
description = ''
|
||
If set to <literal>true</literal>, you are free to add new users and groups to the system
|
||
with the ordinary <literal>useradd</literal> and
|
||
<literal>groupadd</literal> commands. On system activation, the
|
||
existing contents of the <literal>/etc/passwd</literal> and
|
||
<literal>/etc/group</literal> files will be merged with the
|
||
contents generated from the <literal>users.users</literal> and
|
||
<literal>users.groups</literal> options.
|
||
The initial password for a user will be set
|
||
according to <literal>users.users</literal>, but existing passwords
|
||
will not be changed.
|
||
|
||
<warning><para>
|
||
If set to <literal>false</literal>, the contents of the user and
|
||
group files will simply be replaced on system activation. This also
|
||
holds for the user passwords; all changed
|
||
passwords will be reset according to the
|
||
<literal>users.users</literal> configuration on activation.
|
||
</para></warning>
|
||
'';
|
||
};
|
||
|
||
users.enforceIdUniqueness = mkOption {
|
||
type = types.bool;
|
||
default = true;
|
||
description = ''
|
||
Whether to require that no two users/groups share the same uid/gid.
|
||
'';
|
||
};
|
||
|
||
users.users = mkOption {
|
||
default = {};
|
||
type = with types; attrsOf (submodule userOpts);
|
||
example = {
|
||
alice = {
|
||
uid = 1234;
|
||
description = "Alice Q. User";
|
||
home = "/home/alice";
|
||
createHome = true;
|
||
group = "users";
|
||
extraGroups = ["wheel"];
|
||
shell = "/bin/sh";
|
||
};
|
||
};
|
||
description = ''
|
||
Additional user accounts to be created automatically by the system.
|
||
This can also be used to set options for root.
|
||
'';
|
||
};
|
||
|
||
users.groups = mkOption {
|
||
default = {};
|
||
example =
|
||
{ students.gid = 1001;
|
||
hackers = { };
|
||
};
|
||
type = with types; attrsOf (submodule groupOpts);
|
||
description = ''
|
||
Additional groups to be created automatically by the system.
|
||
'';
|
||
};
|
||
|
||
};
|
||
|
||
|
||
###### implementation
|
||
|
||
config = {
|
||
|
||
users.users = {
|
||
root = {
|
||
uid = ids.uids.root;
|
||
description = "System administrator";
|
||
home = "/root";
|
||
shell = mkDefault cfg.defaultUserShell;
|
||
group = "root";
|
||
};
|
||
nobody = {
|
||
uid = ids.uids.nobody;
|
||
description = "Unprivileged account (don't use!)";
|
||
group = "nogroup";
|
||
};
|
||
};
|
||
|
||
users.groups = {
|
||
root.gid = ids.gids.root;
|
||
wheel.gid = ids.gids.wheel;
|
||
disk.gid = ids.gids.disk;
|
||
kmem.gid = ids.gids.kmem;
|
||
tty.gid = ids.gids.tty;
|
||
floppy.gid = ids.gids.floppy;
|
||
uucp.gid = ids.gids.uucp;
|
||
lp.gid = ids.gids.lp;
|
||
cdrom.gid = ids.gids.cdrom;
|
||
tape.gid = ids.gids.tape;
|
||
audio.gid = ids.gids.audio;
|
||
video.gid = ids.gids.video;
|
||
dialout.gid = ids.gids.dialout;
|
||
nogroup.gid = ids.gids.nogroup;
|
||
users.gid = ids.gids.users;
|
||
nixbld.gid = ids.gids.nixbld;
|
||
utmp.gid = ids.gids.utmp;
|
||
adm.gid = ids.gids.adm;
|
||
input.gid = ids.gids.input;
|
||
kvm.gid = ids.gids.kvm;
|
||
render.gid = ids.gids.render;
|
||
shadow.gid = ids.gids.shadow;
|
||
};
|
||
|
||
system.activationScripts.users = stringAfter [ "stdio" ]
|
||
''
|
||
install -m 0700 -d /root
|
||
install -m 0755 -d /home
|
||
|
||
${pkgs.perl}/bin/perl -w \
|
||
-I${pkgs.perlPackages.FileSlurp}/${pkgs.perl.libPrefix} \
|
||
-I${pkgs.perlPackages.JSON}/${pkgs.perl.libPrefix} \
|
||
${./update-users-groups.pl} ${spec}
|
||
'';
|
||
|
||
# for backwards compatibility
|
||
system.activationScripts.groups = stringAfter [ "users" ] "";
|
||
|
||
# Install all the user shells
|
||
environment.systemPackages = systemShells;
|
||
|
||
environment.etc = (mapAttrs' (name: { packages, ... }: {
|
||
name = "profiles/per-user/${name}";
|
||
value.source = pkgs.buildEnv {
|
||
name = "user-environment";
|
||
paths = packages;
|
||
inherit (config.environment) pathsToLink extraOutputsToInstall;
|
||
inherit (config.system.path) ignoreCollisions postBuild;
|
||
};
|
||
}) (filterAttrs (_: u: u.packages != []) cfg.users));
|
||
|
||
environment.profiles = [
|
||
"$HOME/.nix-profile"
|
||
"/etc/profiles/per-user/$USER"
|
||
];
|
||
|
||
assertions = [
|
||
{ assertion = !cfg.enforceIdUniqueness || (uidsAreUnique && gidsAreUnique);
|
||
message = "UIDs and GIDs must be unique!";
|
||
}
|
||
{ # If mutableUsers is false, to prevent users creating a
|
||
# configuration that locks them out of the system, ensure that
|
||
# there is at least one "privileged" account that has a
|
||
# password or an SSH authorized key. Privileged accounts are
|
||
# root and users in the wheel group.
|
||
assertion = !cfg.mutableUsers ->
|
||
any id ((mapAttrsToList (name: cfg:
|
||
(name == "root"
|
||
|| cfg.group == "wheel"
|
||
|| elem "wheel" cfg.extraGroups)
|
||
&&
|
||
(allowsLogin cfg.hashedPassword
|
||
|| cfg.password != null
|
||
|| cfg.passwordFile != null
|
||
|| cfg.openssh.authorizedKeys.keys != []
|
||
|| cfg.openssh.authorizedKeys.keyFiles != [])
|
||
) cfg.users) ++ [
|
||
config.security.googleOsLogin.enable
|
||
]);
|
||
message = ''
|
||
Neither the root account nor any wheel user has a password or SSH authorized key.
|
||
You must set one to prevent being locked out of your system.'';
|
||
}
|
||
] ++ flip mapAttrsToList cfg.users (name: user:
|
||
{
|
||
assertion = (user.hashedPassword != null)
|
||
-> (builtins.match ".*:.*" user.hashedPassword == null);
|
||
message = ''
|
||
The password hash of user "${name}" contains a ":" character.
|
||
This is invalid and would break the login system because the fields
|
||
of /etc/shadow (file where hashes are stored) are colon-separated.
|
||
Please check the value of option `users.users."${name}".hashedPassword`.'';
|
||
}
|
||
);
|
||
|
||
warnings =
|
||
builtins.filter (x: x != null) (
|
||
flip mapAttrsToList cfg.users (name: user:
|
||
# This regex matches a subset of the Modular Crypto Format (MCF)[1]
|
||
# informal standard. Since this depends largely on the OS or the
|
||
# specific implementation of crypt(3) we only support the (sane)
|
||
# schemes implemented by glibc and BSDs. In particular the original
|
||
# DES hash is excluded since, having no structure, it would validate
|
||
# common mistakes like typing the plaintext password.
|
||
#
|
||
# [1]: https://en.wikipedia.org/wiki/Crypt_(C)
|
||
let
|
||
sep = "\\$";
|
||
base64 = "[a-zA-Z0-9./]+";
|
||
id = "[a-z0-9-]+";
|
||
value = "[a-zA-Z0-9/+.-]+";
|
||
options = "${id}(=${value})?(,${id}=${value})*";
|
||
scheme = "${id}(${sep}${options})?";
|
||
content = "${base64}${sep}${base64}";
|
||
mcf = "^${sep}${scheme}${sep}${content}$";
|
||
in
|
||
if (allowsLogin user.hashedPassword
|
||
&& user.hashedPassword != "" # login without password
|
||
&& builtins.match mcf user.hashedPassword == null)
|
||
then ''
|
||
The password hash of user "${name}" may be invalid. You must set a
|
||
valid hash or the user will be locked out of their account. Please
|
||
check the value of option `users.users."${name}".hashedPassword`.''
|
||
else null
|
||
));
|
||
|
||
};
|
||
|
||
}
|