1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<meta http-equiv="Content-Language" content="en" />
<title>nsss: the nsssd-nslcd program</title>
<meta name="Description" content="nsss: the nsssd-nslcd program" />
<meta name="Keywords" content="nsss name service switch nsssd nslcd ldap daemon authentication service nsssd-nslcd" />
<!-- <link rel="stylesheet" type="text/css" href="//skarnet.org/default.css" /> -->
</head>
<body>
<p>
<a href="index.html">nsss</a><br />
<a href="//skarnet.org/software/">Software</a><br />
<a href="//skarnet.org/">skarnet.org</a>
</p>
<h1> The nsssd-nslcd program </h1>
<p>
nsssd-nslcd is a daemon providing a backend for clients using the
<a href="libnsss/">nsss library</a> - more precisely, clients using
the <a href="libnsss/nsss-all.html">nsss-all</a> or
the <a href="libnsss/nsss-switch.html">nsss-switch</a> functions.
</p>
<p>
The nsssd-nslcd backend is meant to be used when the user/group/shadow
information is held in a LDAP server, and the
<a href="https://github.com/arthurdejong/nss-pam-ldapd/tree/master/nslcd">nslcd</a>
daemon is running on the system as an interface to the LDAP architecture.
nsssd-nslcd acts a server for its libnsss-using client, and as a
client to nslcd. It forwards the application's requests to nslcd, and
forwards the answers back.
</p>
<p>
nsssd-nslcd is not meant to be called directly; instead, it is expected to be run from
a script as a part of a "nsssd"
<a href="//skarnet.org/software/s6/localservice.html">local service</a>.
</p>
<p>
The <tt>examples/</tt> subdirectory of the nsss package provides examples
on how to run such a service.
The simplest way to do so, for testing purposes, is a command line such as:
</p>
<pre>s6-ipcserver -l0 /run/service/nsssd/s nsssd-nslcd /var/run/nslcd/socket</pre>
<p>
<tt>/run/service/nsssd/s</tt> is the default place where nsss's
implementation of the <tt>pwd.h</tt>, <tt>grp.h</tt> and <tt>shadow.h</tt>
functions expects the nsssd
service to be. It can be changed at nsss build time by giving the
<tt>--with-nsssd-socket=PATH</tt> option to configure.
nsssd-nslcd takes one argument: the path to connect to the nslcd daemon.
By default, this is <tt>/var/run/nslcd/socket</tt>. The default can be
changed at nslcd build time.
</p>
<p>
nsssd-nslcd does not listen to the socket itself: it reads from its
standard input and writes to its standard output. It relies
on a superserver such as
<a href="//skarnet.org/software/s6/s6-ipcserver.html">s6-ipcserver</a>
to manage connections to the socket. An instance of nsssd-nslcd is run
for every client connection.
</p>
<p>
If fine-grained authorizations are required (only allowing
certain users and groups to connect to the service), the superserver
can be configured to enforce them.
</p>
<p>
nsssd-nslcd does not need to run as root, provided it can connect
to the nslcd daemon.
It is recommended to create a <em>nsss</em> user and group, dedicated to
the nsssd service, and run the superserver as this user and group.
</p>
</body>
</html>
|
