105 lines
4.1 KiB
XML
105 lines
4.1 KiB
XML
<chapter xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xml:id="sec-user-management">
|
||
<title>User Management</title>
|
||
<para>
|
||
NixOS supports both declarative and imperative styles of user
|
||
management. In the declarative style, users are specified in
|
||
<literal>configuration.nix</literal>. For instance, the following
|
||
states that a user account named <literal>alice</literal> shall
|
||
exist:
|
||
</para>
|
||
<programlisting language="bash">
|
||
users.users.alice = {
|
||
isNormalUser = true;
|
||
home = "/home/alice";
|
||
description = "Alice Foobar";
|
||
extraGroups = [ "wheel" "networkmanager" ];
|
||
openssh.authorizedKeys.keys = [ "ssh-dss AAAAB3Nza... alice@foobar" ];
|
||
};
|
||
</programlisting>
|
||
<para>
|
||
Note that <literal>alice</literal> is a member of the
|
||
<literal>wheel</literal> and <literal>networkmanager</literal>
|
||
groups, which allows her to use <literal>sudo</literal> to execute
|
||
commands as <literal>root</literal> and to configure the network,
|
||
respectively. Also note the SSH public key that allows remote logins
|
||
with the corresponding private key. Users created in this way do not
|
||
have a password by default, so they cannot log in via mechanisms
|
||
that require a password. However, you can use the
|
||
<literal>passwd</literal> program to set a password, which is
|
||
retained across invocations of <literal>nixos-rebuild</literal>.
|
||
</para>
|
||
<para>
|
||
If you set <xref linkend="opt-users.mutableUsers" /> to false, then
|
||
the contents of <literal>/etc/passwd</literal> and
|
||
<literal>/etc/group</literal> will be congruent to your NixOS
|
||
configuration. For instance, if you remove a user from
|
||
<xref linkend="opt-users.users" /> and run nixos-rebuild, the user
|
||
account will cease to exist. Also, imperative commands for managing
|
||
users and groups, such as useradd, are no longer available.
|
||
Passwords may still be assigned by setting the user's
|
||
<link linkend="opt-users.users._name_.hashedPassword">hashedPassword</link>
|
||
option. A hashed password can be generated using
|
||
<literal>mkpasswd -m sha-512</literal>.
|
||
</para>
|
||
<para>
|
||
A user ID (uid) is assigned automatically. You can also specify a
|
||
uid manually by adding
|
||
</para>
|
||
<programlisting language="bash">
|
||
uid = 1000;
|
||
</programlisting>
|
||
<para>
|
||
to the user specification.
|
||
</para>
|
||
<para>
|
||
Groups can be specified similarly. The following states that a group
|
||
named <literal>students</literal> shall exist:
|
||
</para>
|
||
<programlisting language="bash">
|
||
users.groups.students.gid = 1000;
|
||
</programlisting>
|
||
<para>
|
||
As with users, the group ID (gid) is optional and will be assigned
|
||
automatically if it’s missing.
|
||
</para>
|
||
<para>
|
||
In the imperative style, users and groups are managed by commands
|
||
such as <literal>useradd</literal>, <literal>groupmod</literal> and
|
||
so on. For instance, to create a user account named
|
||
<literal>alice</literal>:
|
||
</para>
|
||
<programlisting>
|
||
# useradd -m alice
|
||
</programlisting>
|
||
<para>
|
||
To make all nix tools available to this new user use `su - USER`
|
||
which opens a login shell (==shell that loads the profile) for given
|
||
user. This will create the ~/.nix-defexpr symlink. So run:
|
||
</para>
|
||
<programlisting>
|
||
# su - alice -c "true"
|
||
</programlisting>
|
||
<para>
|
||
The flag <literal>-m</literal> causes the creation of a home
|
||
directory for the new user, which is generally what you want. The
|
||
user does not have an initial password and therefore cannot log in.
|
||
A password can be set using the <literal>passwd</literal> utility:
|
||
</para>
|
||
<programlisting>
|
||
# passwd alice
|
||
Enter new UNIX password: ***
|
||
Retype new UNIX password: ***
|
||
</programlisting>
|
||
<para>
|
||
A user can be deleted using <literal>userdel</literal>:
|
||
</para>
|
||
<programlisting>
|
||
# userdel -r alice
|
||
</programlisting>
|
||
<para>
|
||
The flag <literal>-r</literal> deletes the user’s home directory.
|
||
Accounts can be modified using <literal>usermod</literal>. Unix
|
||
groups can be managed using <literal>groupadd</literal>,
|
||
<literal>groupmod</literal> and <literal>groupdel</literal>.
|
||
</para>
|
||
</chapter>
|