5 <firstname>Tim</firstname><surname>Potter</surname>
7 <orgname>Samba Team</orgname>
8 <address><email>tpot@linuxcare.com.au</email></address>
13 <firstname>Naag</firstname><surname>Mummaneni</surname>
15 <address><email>getnag@rediffmail.com</email></address>
17 <contrib>Notes for Solaris</contrib>
20 <firstname>John</firstname><surname>Trostel</surname>
22 <address><email>jtrostel@snapserver.com</email></address>
23 <orgname>SNAP</orgname>
29 <pubdate>27 June 2002</pubdate>
32 <title>Winbind: Use of Domain Accounts</title>
35 <title>Features and Benefits</title>
38 Integration of UNIX and Microsoft Windows NT through a unified logon has
39 been considered a <quote>holy grail</quote> in heterogeneous computing environments for
44 There is one other facility without which UNIX and Microsoft Windows network
45 interoperability would suffer greatly. It is imperative that there be a
46 mechanism for sharing files across UNIX systems and to be able to assign
47 domain user and group ownerships with integrity.
51 <emphasis>winbind</emphasis> is a component of the Samba suite of programs that
52 solves the unified logon problem. Winbind uses a UNIX implementation of Microsoft
53 RPC calls, Pluggable Authentication Modules, and the Name Service Switch to
54 allow Windows NT domain users to appear and operate as UNIX users on a UNIX
55 machine. This chapter describes the Winbind system, explaining the functionality
56 it provides, how it is configured, and how it works internally.
60 Winbind provides three separate functions:
65 Authentication of user credentials (via PAM).
69 Identity resolution (via NSS).
73 Winbind maintains a database called winbind_idmap.tdb in which it stores
74 mappings between UNIX UIDs / GIDs and NT SIDs. This mapping is used only
75 for users and groups that do not have a local UID/GID. It stored the UID/GID
76 allocated from the idmap uid/gid range that it has mapped to the NT SID.
77 If <parameter>idmap backend</parameter> has been specified as ldapsam:url
78 then instead of using a local mapping Winbind will obtain this information
79 from the LDAP database.
84 <indexterm><primary>winbindd</primary></indexterm>
85 <indexterm><primary>starting samba</primary><secondary>winbindd</secondary></indexterm>
86 If <command>winbindd</command> is not running, smbd (which calls <command>winbindd</command>) will fall back to
87 using purely local information from <filename>/etc/passwd</filename> and <filename>/etc/group</filename> and no dynamic
92 <!-- <figure id="winbind_idmap"><title></title>
94 <imageobject role="latex"><imagedata fileref="projdoc/imagefiles/idmap_winbind_no_loop" scale="50" scalefit="1"/></imageobject>
95 <imageobject><imagedata fileref="projdoc/imagefiles/idmap_winbind_no_loop.png" scale="50" scalefit="1"/></imageobject>
103 <title>Introduction</title>
105 <para>It is well known that UNIX and Microsoft Windows NT have
106 different models for representing user and group information and
107 use different technologies for implementing them. This fact has
108 made it difficult to integrate the two systems in a satisfactory
111 <para>One common solution in use today has been to create
112 identically named user accounts on both the UNIX and Windows systems
113 and use the Samba suite of programs to provide file and print services
114 between the two. This solution is far from perfect, however, as
115 adding and deleting users on both sets of machines becomes a chore
116 and two sets of passwords are required &smbmdash; both of which
117 can lead to synchronization problems between the UNIX and Windows
118 systems and confusion for users.</para>
120 <para>We divide the unified logon problem for UNIX machines into
121 three smaller problems:</para>
124 <listitem><para>Obtaining Windows NT user and group information.
127 <listitem><para>Authenticating Windows NT users.
130 <listitem><para>Password changing for Windows NT users.
135 <para>Ideally, a prospective solution to the unified logon problem
136 would satisfy all the above components without duplication of
137 information on the UNIX machines and without creating additional
138 tasks for the system administrator when maintaining users and
139 groups on either system. The Winbind system provides a simple
140 and elegant solution to all three components of the unified logon
146 <title>What Winbind Provides</title>
148 <para>Winbind unifies UNIX and Windows NT account management by
149 allowing a UNIX box to become a full member of an NT domain. Once
150 this is done the UNIX box will see NT users and groups as if
151 they were <quote>native</quote> UNIX users and groups, allowing the NT domain
152 to be used in much the same manner that NIS+ is used within
153 UNIX-only environments.</para>
155 <para>The end result is that whenever any
156 program on the UNIX machine asks the operating system to lookup
157 a user or group name, the query will be resolved by asking the
158 NT Domain Controller for the specified domain to do the lookup.
159 Because Winbind hooks into the operating system at a low level
160 (via the NSS name resolution modules in the C library), this
161 redirection to the NT Domain Controller is completely
164 <para>Users on the UNIX machine can then use NT user and group
165 names as they would <quote>native</quote> UNIX names. They can chown files
166 so they are owned by NT domain users or even login to the
167 UNIX machine and run a UNIX X-Window session as a domain user.</para>
169 <para>The only obvious indication that Winbind is being used is
170 that user and group names take the form <constant>DOMAIN\user</constant> and
171 <constant>DOMAIN\group</constant>. This is necessary as it allows Winbind to determine
172 that redirection to a Domain Controller is wanted for a particular
173 lookup and which trusted domain is being referenced.</para>
175 <para>Additionally, Winbind provides an authentication service
176 that hooks into the Pluggable Authentication Modules (PAM) system
177 to provide authentication via an NT domain to any PAM-enabled
178 applications. This capability solves the problem of synchronizing
179 passwords between systems since all passwords are stored in a single
180 location (on the Domain Controller).</para>
183 <title>Target Uses</title>
185 <para>Winbind is targeted at organizations that have an
186 existing NT-based domain infrastructure into which they wish
187 to put UNIX workstations or servers. Winbind will allow these
188 organizations to deploy UNIX workstations without having to
189 maintain a separate account infrastructure. This greatly
190 simplifies the administrative overhead of deploying UNIX
191 workstations into an NT-based organization.</para>
193 <para>Another interesting way in which we expect Winbind to
194 be used is as a central part of UNIX-based appliances. Appliances
195 that provide file and print services to Microsoft-based networks
196 will be able to use Winbind to provide seamless integration of
197 the appliance into the domain.</para>
204 <title>How Winbind Works</title>
206 <para>The Winbind system is designed around a client/server
207 architecture. A long running <command>winbindd</command> daemon
208 listens on a UNIX domain socket waiting for requests
209 to arrive. These requests are generated by the NSS and PAM
210 clients and is processed sequentially.</para>
212 <para>The technologies used to implement Winbind are described
213 in detail below.</para>
216 <title>Microsoft Remote Procedure Calls</title>
218 <para>Over the last few years, efforts have been underway
219 by various Samba Team members to decode various aspects of
220 the Microsoft Remote Procedure Call (MSRPC) system. This
221 system is used for most network-related operations between
222 Windows NT machines including remote management, user authentication
223 and print spooling. Although initially this work was done
224 to aid the implementation of Primary Domain Controller (PDC)
225 functionality in Samba, it has also yielded a body of code that
226 can be used for other purposes.</para>
228 <para>Winbind uses various MSRPC calls to enumerate domain users
229 and groups and to obtain detailed information about individual
230 users or groups. Other MSRPC calls can be used to authenticate
231 NT domain users and to change user passwords. By directly querying
232 a Windows PDC for user and group information, Winbind maps the
233 NT account information onto UNIX user and group names.</para>
237 <title>Microsoft Active Directory Services</title>
240 Since late 2001, Samba has gained the ability to
241 interact with Microsoft Windows 2000 using its <quote>Native
242 Mode</quote> protocols, rather than the NT4 RPC services.
243 Using LDAP and Kerberos, a Domain Member running
244 Winbind can enumerate users and groups in exactly the
245 same way as a Windows 200x client would, and in so doing
246 provide a much more efficient and effective Winbind implementation.
251 <title>Name Service Switch</title>
253 <para>The Name Service Switch, or NSS, is a feature that is
254 present in many UNIX operating systems. It allows system
255 information such as hostnames, mail aliases and user information
256 to be resolved from different sources. For example, a standalone
257 UNIX workstation may resolve system information from a series of
258 flat files stored on the local filesystem. A networked workstation
259 may first attempt to resolve system information from local files,
260 and then consult an NIS database for user information or a DNS server
261 for hostname information.</para>
263 <para>The NSS application programming interface allows Winbind
264 to present itself as a source of system information when
265 resolving UNIX usernames and groups. Winbind uses this interface,
266 and information obtained from a Windows NT server using MSRPC
267 calls to provide a new source of account enumeration. Using standard
268 UNIX library calls, one can enumerate the users and groups on
269 a UNIX machine running Winbind and see all users and groups in
270 a NT domain plus any trusted domain as though they were local
271 users and groups.</para>
273 <para>The primary control file for NSS is
274 <filename>/etc/nsswitch.conf</filename>.
275 When a UNIX application makes a request to do a lookup,
276 the C library looks in <filename>/etc/nsswitch.conf</filename>
277 for a line that matches the service type being requested, for
278 example the <quote>passwd</quote> service type is used when user or group names
279 are looked up. This config line specifies which implementations
280 of that service should be tried and in what order. If the passwd
281 config line is:</para>
284 passwd: files example
287 <para>then the C library will first load a module called
288 <filename>/lib/libnss_files.so</filename> followed by
289 the module <filename>/lib/libnss_example.so</filename>. The
290 C library will dynamically load each of these modules in turn
291 and call resolver functions within the modules to try to resolve
292 the request. Once the request is resolved, the C library returns the
293 result to the application.</para>
295 <para>This NSS interface provides an easy way for Winbind
296 to hook into the operating system. All that needs to be done
297 is to put <filename>libnss_winbind.so</filename> in <filename>/lib/</filename>
298 then add <quote>winbind</quote> into <filename>/etc/nsswitch.conf</filename> at
299 the appropriate place. The C library will then call Winbind to
300 resolve user and group names.</para>
304 <title>Pluggable Authentication Modules</title>
306 <para>Pluggable Authentication Modules, also known as PAM,
307 is a system for abstracting authentication and authorization
308 technologies. With a PAM module it is possible to specify different
309 authentication methods for different system applications without
310 having to recompile these applications. PAM is also useful
311 for implementing a particular policy for authorization. For example,
312 a system administrator may only allow console logins from users
313 stored in the local password file but only allow users resolved from
314 a NIS database to log in over the network.</para>
316 <para>Winbind uses the authentication management and password
317 management PAM interface to integrate Windows NT users into a
318 UNIX system. This allows Windows NT users to log in to a UNIX
319 machine and be authenticated against a suitable Primary Domain
320 Controller. These users can also change their passwords and have
321 this change take effect directly on the Primary Domain Controller.
324 <para>PAM is configured by providing control files in the directory
325 <filename>/etc/pam.d/</filename> for each of the services that
326 require authentication. When an authentication request is made
327 by an application, the PAM code in the C library looks up this
328 control file to determine what modules to load to do the
329 authentication check and in what order. This interface makes adding
330 a new authentication service for Winbind very easy. All that needs
331 to be done is that the <filename>pam_winbind.so</filename> module
332 is copied to <filename>/lib/security/</filename> and the PAM
333 control files for relevant services are updated to allow
334 authentication via Winbind. See the PAM documentation
335 in <link linkend="pam">PAM-Based Distributed Authentication</link> for more information.</para>
340 <title>User and Group ID Allocation</title>
342 <para>When a user or group is created under Windows NT/200x
343 it is allocated a numerical relative identifier (RID). This is
344 slightly different from UNIX which has a range of numbers that are
345 used to identify users, and the same range in which to identify
346 groups. It is Winbind's job to convert RIDs to UNIX ID numbers and
347 vice versa. When Winbind is configured, it is given part of the UNIX
348 user ID space and a part of the UNIX group ID space in which to
349 store Windows NT users and groups. If a Windows NT user is
350 resolved for the first time, it is allocated the next UNIX ID from
351 the range. The same process applies for Windows NT groups. Over
352 time, Winbind will have mapped all Windows NT users and groups
353 to UNIX user IDs and group IDs.</para>
355 <para>The results of this mapping are stored persistently in
356 an ID mapping database held in a tdb database). This ensures that
357 RIDs are mapped to UNIX IDs in a consistent way.</para>
362 <title>Result Caching</title>
365 <indexterm><primary>SAM</primary></indexterm>
366 An active system can generate a lot of user and group
367 name lookups. To reduce the network cost of these lookups, Winbind
368 uses a caching scheme based on the SAM sequence number supplied
369 by NT Domain Controllers. User or group information returned
370 by a PDC is cached by Winbind along with a sequence number also
371 returned by the PDC. This sequence number is incremented by
372 Windows NT whenever any user or group information is modified. If
373 a cached entry has expired, the sequence number is requested from
374 the PDC and compared against the sequence number of the cached entry.
375 If the sequence numbers do not match, then the cached information
376 is discarded and up-to-date information is requested directly
383 <title>Installation and Configuration</title>
386 <title>Introduction</title>
389 This section describes the procedures used to get Winbind up and
390 running. Winbind is capable of providing access
391 and authentication control for Windows Domain users through an NT
392 or Windows 200x PDC for regular services, such as telnet and ftp, as
393 well for Samba services.
399 <emphasis>Why should I do this?</emphasis>
402 <para>This allows the Samba administrator to rely on the
403 authentication mechanisms on the Windows NT/200x PDC for the authentication
404 of Domain Members. Windows NT/200x users no longer need to have separate
405 accounts on the Samba server.
411 <emphasis>Who should be reading this document?</emphasis>
415 This document is designed for system administrators. If you are
416 implementing Samba on a file server and wish to (fairly easily)
417 integrate existing Windows NT/200x users from your PDC onto the
418 Samba server, this document is for you.
426 <title>Requirements</title>
429 If you have a Samba configuration file that you are currently using, <emphasis>BACK IT UP!</emphasis>
430 If your system already uses PAM, <emphasis>back up the <filename>/etc/pam.d</filename> directory
431 contents!</emphasis> If you haven't already made a boot disk, <emphasis>MAKE ONE NOW!</emphasis>
435 Messing with the PAM configuration files can make it nearly impossible to log in to your machine. That's
436 why you want to be able to boot back into your machine in single user mode and restore your
437 <filename>/etc/pam.d</filename> back to the original state they were in if you get frustrated with the
438 way things are going.
442 The latest version of Samba-3 includes a functioning winbindd daemon. Please refer to the <ulink
443 url="http://samba.org/">main Samba Web page</ulink> or, better yet, your closest Samba mirror site for
444 instructions on downloading the source code.
448 To allow domain users the ability to access Samba shares and files, as well as potentially other services
449 provided by your Samba machine, PAM must be set up properly on your
450 machine. In order to compile the Winbind modules, you should have at least the PAM development libraries installed
451 on your system. Please refer the PAM web site <ulink url="http://www.kernel.org/pub/linux/libs/pam/"/>.
456 <title>Testing Things Out</title>
459 Before starting, it is probably best to kill off all the Samba-related daemons running on your server.
460 Kill off all &smbd;, &nmbd;, and &winbindd; processes that may be running. To use PAM,
461 make sure that you have the standard PAM package that supplies the <filename>/etc/pam.d</filename>
462 directory structure, including the PAM modules that are used by PAM-aware services, several pam libraries,
463 and the <filename>/usr/doc</filename> and <filename>/usr/man</filename> entries for pam. Winbind built
464 better in Samba if the pam-devel package is also installed. This package includes the header files
465 needed to compile PAM-aware applications.
469 <title>Configure <filename>nsswitch.conf</filename> and the Winbind Libraries on Linux and Solaris</title>
472 PAM is a standard component of most current generation UNIX/Linux systems. Unfortunately, few systems install
473 the <filename>pam-devel</filename> libraries that are needed to build PAM-enabled Samba. Additionally, Samba-3
474 may auto-install the Winbind files into their correct locations on your system, so before you get too far down
475 the track be sure to check if the following configuration is really
476 necessary. You may only need to configure
477 <filename>/etc/nsswitch.conf</filename>.
481 The libraries needed to run the &winbindd; daemon through nsswitch need to be copied to their proper locations:
486 &rootprompt;<userinput>cp ../samba/source/nsswitch/libnss_winbind.so /lib</userinput>
491 I also found it necessary to make the following symbolic link:
495 &rootprompt; <userinput>ln -s /lib/libnss_winbind.so /lib/libnss_winbind.so.2</userinput>
498 <para>And, in the case of Sun Solaris:</para>
500 &rootprompt;<userinput>ln -s /usr/lib/libnss_winbind.so /usr/lib/libnss_winbind.so.1</userinput>
501 &rootprompt;<userinput>ln -s /usr/lib/libnss_winbind.so /usr/lib/nss_winbind.so.1</userinput>
502 &rootprompt;<userinput>ln -s /usr/lib/libnss_winbind.so /usr/lib/nss_winbind.so.2</userinput>
506 Now, as root you need to edit <filename>/etc/nsswitch.conf</filename> to
507 allow user and group entries to be visible from the &winbindd;
508 daemon. My <filename>/etc/nsswitch.conf</filename> file look like
512 <para><programlisting>
513 passwd: files winbind
516 </programlisting></para>
519 The libraries needed by the <command>winbindd</command> daemon will be automatically
520 entered into the <command>ldconfig</command> cache the next time
521 your system reboots, but it is faster (and you do not need to reboot) if you do it manually:
525 &rootprompt;<userinput>/sbin/ldconfig -v | grep winbind</userinput>
529 This makes <filename>libnss_winbind</filename> available to winbindd
530 and echos back a check to you.
536 <title>NSS Winbind on AIX</title>
538 <para>(This section is only for those running AIX.)</para>
541 The Winbind AIX identification module gets built as <filename>libnss_winbind.so</filename> in the
542 nsswitch directory of the Samba source. This file can be copied to <filename>/usr/lib/security</filename>,
543 and the AIX naming convention would indicate that it should be named WINBIND. A stanza like the following:
546 <para><programlisting>
548 program = /usr/lib/security/WINBIND
550 </programlisting></para>
553 can then be added to <filename>/usr/lib/security/methods.cfg</filename>. This module only supports
554 identification, but there have been success reports using the standard Winbind PAM module for
555 authentication. Use caution configuring loadable authentication
556 modules since you can make
557 it impossible to logon to the system. More information about the AIX authentication module API can
558 be found at <quote>Kernel Extensions and Device Support Programming Concepts for AIX</quote><ulink
559 url="http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixprggd/kernextc/sec_load_mod.htm">
560 in Chapter 18(John, there is no section like this in 18). Loadable Authentication Module Programming
561 Interface</ulink> and more information on administering the modules
562 can be found at <ulink
563 url="http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixbman/baseadmn/iandaadmin.htm"> <quote>System
564 Management Guide: Operating System and Devices.</quote></ulink>
569 <title>Configure smb.conf</title>
572 Several parameters are needed in the &smb.conf; file to control the behavior of &winbindd;. These
573 are described in more detail in the <citerefentry><refentrytitle>winbindd</refentrytitle>
574 <manvolnum>8</manvolnum></citerefentry> man page. My &smb.conf; file, as shown in <link
575 linkend="winbindcfg">the next example</link>, was modified to include the necessary entries in the [global] section.
578 <para><smbconfexample id="winbindcfg">
579 <title>smb.conf for Winbind set-up</title>
580 <smbconfsection>[global]</smbconfsection>
582 <smbconfcomment> separate domain and username with '+', like DOMAIN+username</smbconfcomment>
583 <smbconfoption><name>winbind separator</name><value>+</value></smbconfoption>
584 <smbconfcomment> use uids from 10000 to 20000 for domain users</smbconfcomment>
585 <smbconfoption><name>idmap uid</name><value>10000-20000</value></smbconfoption>
586 <smbconfcomment> use gids from 10000 to 20000 for domain groups</smbconfcomment>
587 <smbconfoption><name>idmap gid</name><value>10000-20000</value></smbconfoption>
588 <smbconfcomment> allow enumeration of winbind users and groups</smbconfcomment>
589 <smbconfoption><name>winbind enum users</name><value>yes</value></smbconfoption>
590 <smbconfoption><name>winbind enum groups</name><value>yes</value></smbconfoption>
591 <smbconfcomment> give winbind users a real shell (only needed if they have telnet access)</smbconfcomment>
592 <smbconfoption><name>template homedir</name><value>/home/winnt/%D/%U</value></smbconfoption>
593 <smbconfoption><name>template shell</name><value>/bin/bash</value></smbconfoption>
594 </smbconfexample></para>
600 <title>Join the Samba Server to the PDC Domain</title>
603 Enter the following command to make the Samba server join the
604 PDC domain, where <replaceable>DOMAIN</replaceable> is the name of
605 your Windows domain and <replaceable>Administrator</replaceable> is
606 a domain user who has administrative privileges in the domain.
611 &rootprompt;<userinput>/usr/local/samba/bin/net rpc join -S PDC -U Administrator</userinput>
616 The proper response to the command should be: <quote>Joined the domain
617 <replaceable>DOMAIN</replaceable></quote> where <replaceable>DOMAIN</replaceable>
624 <title>Starting and Testing the <command>winbindd</command> Daemon</title>
627 Eventually, you will want to modify your Samba startup script to
628 automatically invoke the winbindd daemon when the other parts of
629 Samba start, but it is possible to test out just the Winbind
630 portion first. To start up Winbind services, enter the following
635 &rootprompt;<userinput>/usr/local/samba/bin/winbindd</userinput>
639 The above assumes that Samba has been installed in the <filename>/usr/local/samba</filename>
640 directory tree. You may need to search for the location of Samba files if this is not the
641 location of <command>winbindd</command> on your system.
645 Winbindd can now also run in <quote>dual daemon mode</quote>. This will make it
646 run as two processes. The first will answer all requests from the cache,
647 thus making responses to clients faster. The other will
648 update the cache for the query that the first has just responded.
649 The advantage of this is that responses stay accurate and are faster.
650 You can enable dual daemon mode by adding <option>-B</option> to the command-line:
654 &rootprompt;<userinput>/usr/local/samba/bin/winbindd -B</userinput>
658 I'm always paranoid and like to make sure the daemon is really running.
662 &rootprompt;<userinput>ps -ae | grep winbindd</userinput>
665 This command should produce output like this, if the daemon is running you would expect
666 to see a report something like this:
669 3025 ? 00:00:00 winbindd
673 Now, for the real test, try to get some information about the users on your PDC:
677 &rootprompt;<userinput>/usr/local/samba/bin/wbinfo -u</userinput>
681 This should echo back a list of users on your Windows users on
682 your PDC. For example, I get the following response:
695 Obviously, I have named my domain <quote>CEO</quote> and my <smbconfoption><name>winbind separator</name></smbconfoption> is <quote>+</quote>.
699 You can do the same sort of thing to get group information from the PDC:
703 &rootprompt;<userinput>/usr/local/samba/bin/wbinfo -g</userinput>
708 CEO+Domain Controllers
711 CEO+Enterprise Admins
712 CEO+Group Policy Creator Owners
716 The function <command>getent</command> can now be used to get unified
717 lists of both local and PDC users and groups. Try the following command:
721 &rootprompt;<userinput>getent passwd</userinput>
725 You should get a list that looks like your <filename>/etc/passwd</filename>
726 list followed by the domain users with their new UIDs, GIDs, home
727 directories and default shells.
731 The same thing can be done for groups with the command:
735 &rootprompt;<userinput>getent group</userinput>
742 <title>Fix the init.d Startup Scripts</title>
748 The &winbindd; daemon needs to start up after the &smbd; and &nmbd; daemons are running.
749 To accomplish this task, you need to modify the startup scripts of your system.
750 They are located at <filename>/etc/init.d/smb</filename> in Red Hat Linux and they are located in
751 <filename>/etc/init.d/samba</filename> in Debian Linux. Edit your
752 script to add commands to invoke this daemon in the proper sequence. My
753 startup script starts up &smbd;, &nmbd;, and &winbindd; from the
754 <filename>/usr/local/samba/bin</filename> directory directly. The <command>start</command>
755 function in the script looks like this:
758 <para><programlisting>
761 echo -n $"Starting $KIND services: "
762 daemon /usr/local/samba/bin/smbd $SMBDOPTIONS
766 echo -n $"Starting $KIND services: "
767 daemon /usr/local/samba/bin/nmbd $NMBDOPTIONS
771 echo -n $"Starting $KIND services: "
772 daemon /usr/local/samba/bin/winbindd
775 [ $RETVAL -eq 0 -a $RETVAL2 -eq 0 -a $RETVAL3 -eq 0 ] && \
776 touch /var/lock/subsys/smb || RETVAL=1
779 </programlisting></para>
781 <para>If you would like to run winbindd in dual daemon mode, replace
784 daemon /usr/local/samba/bin/winbindd
787 in the example above with:
790 daemon /usr/local/samba/bin/winbindd -B
795 The <command>stop</command> function has a corresponding entry to shut down the
796 services and looks like this:
799 <para><programlisting>
802 echo -n $"Shutting down $KIND services: "
807 echo -n $"Shutting down $KIND services: "
812 echo -n $"Shutting down $KIND services: "
815 [ $RETVAL -eq 0 -a $RETVAL2 -eq 0 -a $RETVAL3 -eq 0 ] && \
816 rm -f /var/lock/subsys/smb
820 </programlisting></para>
824 <title>Solaris</title>
827 Winbind does not work on Solaris 9, see <link linkend="winbind-solaris9">Winbind on Solaris 9</link> section for details.
831 On Solaris, you need to modify the <filename>/etc/init.d/samba.server</filename> startup script. It
832 usually only starts smbd and nmbd but should now start winbindd, too. If you have Samba installed in
833 <filename>/usr/local/samba/bin</filename>, the file could contains something like this:
837 <smbfile name="samba.server.sh">
844 then # /usr not mounted
848 killproc() { # kill the named process(es)
849 pid=`/usr/bin/ps -e |
850 /usr/bin/grep -w $1 |
851 /usr/bin/sed -e 's/^ *//' -e 's/ .*//'`
852 [ "$pid" != "" ] && kill $pid
855 # Start/stop processes required for Samba server
861 # Edit these lines to suit your installation (paths, workgroup, host)
864 /usr/local/samba/bin/smbd -D -s \
865 /usr/local/samba/smb.conf
868 /usr/local/samba/bin/nmbd -D -l \
869 /usr/local/samba/var/log -s /usr/local/samba/smb.conf
871 echo Starting Winbind Daemon
872 /usr/local/samba/bin/winbindd
882 echo "Usage: /etc/init.d/samba.server { start | stop }"
885 </programlisting></smbfile></para>
888 Again, if you would like to run Samba in dual daemon mode, replace:
890 /usr/local/samba/bin/winbindd
892 in the script above with:
894 /usr/local/samba/bin/winbindd -B
901 <title>Restarting</title>
903 If you restart the &smbd;, &nmbd;, and &winbindd; daemons at this point, you
904 should be able to connect to the Samba server as a Domain Member just as
905 if you were a local user.
911 <title>Configure Winbind and PAM</title>
914 If you have made it this far, you know that <command>winbindd</command> and Samba are working
915 together. If you want to use Winbind to provide authentication for other
916 services, keep reading. The PAM configuration files need to be altered in
917 this step. (Did you remember to make backups of your original
918 <filename>/etc/pam.d</filename> files? If not, do it now.)
922 You will need a PAM module to use winbindd with these other services. This
923 module will be compiled in the <filename>../source/nsswitch</filename> directory
924 by invoking the command:
928 &rootprompt;<userinput>make nsswitch/pam_winbind.so</userinput>
932 from the <filename>../source</filename> directory. The
933 <filename>pam_winbind.so</filename> file should be copied to the location of
934 your other PAM security modules. On my Red Hat system, this was the
935 <filename>/lib/security</filename> directory. On Solaris, the PAM security
936 modules reside in <filename>/usr/lib/security</filename>.
940 &rootprompt;<userinput>cp ../samba/source/nsswitch/pam_winbind.so /lib/security</userinput>
944 <title>Linux/FreeBSD-specific PAM configuration</title>
947 The <filename>/etc/pam.d/samba</filename> file does not need to be changed. I
948 just left this file as it was:
952 <para><programlisting>
953 auth required /lib/security/pam_stack.so service=system-auth
954 account required /lib/security/pam_stack.so service=system-auth
955 </programlisting></para>
958 The other services that I modified to allow the use of Winbind
959 as an authentication service were the normal login on the console (or a terminal
960 session), telnet logins, and ftp service. In order to enable these
961 services, you may first need to change the entries in
962 <filename>/etc/xinetd.d</filename> (or <filename>/etc/inetd.conf</filename>).
963 Red Hat Linux 7.1 and later uses the new xinetd.d structure, in this case you need
964 to change the lines in <filename>/etc/xinetd.d/telnet</filename>
965 and <filename>/etc/xinetd.d/wu-ftp</filename> from
968 <para><programlisting>
974 </programlisting></para>
977 For ftp services to work properly, you will also need to either
978 have individual directories for the domain users already present on
979 the server, or change the home directory template to a general
980 directory for all domain users. These can be easily set using
981 the &smb.conf; global entry
982 <smbconfoption><name>template homedir</name></smbconfoption>.
986 <para>The directory in <smbconfoption><name>template homedir</name></smbconfoption> is not created automatically! Use pam_mkhomedir or pre-create
987 the directories of users to make sure users can log in on UNIX with
988 their own home directory.
993 The <filename>/etc/pam.d/ftp</filename> file can be changed
994 to allow Winbind ftp access in a manner similar to the
995 samba file. My <filename>/etc/pam.d/ftp</filename> file was
996 changed to look like this:
999 <para><smbfile name="pam.ftp.winbind"><programlisting>
1000 auth required /lib/security/pam_listfile.so item=user sense=deny \
1001 file=/etc/ftpusers onerr=succeed
1002 auth sufficient /lib/security/pam_winbind.so
1003 auth required /lib/security/pam_stack.so service=system-auth
1004 auth required /lib/security/pam_shells.so
1005 account sufficient /lib/security/pam_winbind.so
1006 account required /lib/security/pam_stack.so service=system-auth
1007 session required /lib/security/pam_stack.so service=system-auth
1008 </programlisting></smbfile></para>
1011 The <filename>/etc/pam.d/login</filename> file can be changed nearly the
1012 same way. It now looks like this:
1015 <para><smbfile name="pam.login.winbind"><programlisting>
1016 auth required /lib/security/pam_securetty.so
1017 auth sufficient /lib/security/pam_winbind.so
1018 auth sufficient /lib/security/pam_unix.so use_first_pass
1019 auth required /lib/security/pam_stack.so service=system-auth
1020 auth required /lib/security/pam_nologin.so
1021 account sufficient /lib/security/pam_winbind.so
1022 account required /lib/security/pam_stack.so service=system-auth
1023 password required /lib/security/pam_stack.so service=system-auth
1024 session required /lib/security/pam_stack.so service=system-auth
1025 session optional /lib/security/pam_console.so
1026 </programlisting></smbfile></para>
1029 In this case, I added the <programlisting>auth sufficient /lib/security/pam_winbind.so</programlisting>
1030 lines as before, but also added the <programlisting>required pam_securetty.so</programlisting>
1031 above it, to disallow root logins over the network. I also added a
1032 <programlisting>sufficient /lib/security/pam_unix.so use_first_pass</programlisting>
1033 line after the <command>winbind.so</command> line to get rid of annoying
1034 double prompts for passwords.
1040 <title>Solaris-specific configuration</title>
1043 The <filename>/etc/pam.conf</filename> needs to be changed. I changed this file so my Domain
1044 users can logon both locally as well as telnet. The following are the changes
1045 that I made. You can customize the <filename>pam.conf</filename> file as per your requirements, but
1046 be sure of those changes because in the worst case it will leave your system
1047 nearly impossible to boot.
1050 <para><programlisting>
1052 #ident "@(#)pam.conf 1.14 99/09/16 SMI"
1054 # Copyright (c) 1996-1999, Sun Microsystems, Inc.
1055 # All Rights Reserved.
1059 # Authentication management
1061 login auth required /usr/lib/security/pam_winbind.so
1062 login auth required /usr/lib/security/$ISA/pam_unix.so.1 try_first_pass
1063 login auth required /usr/lib/security/$ISA/pam_dial_auth.so.1 try_first_pass
1065 rlogin auth sufficient /usr/lib/security/pam_winbind.so
1066 rlogin auth sufficient /usr/lib/security/$ISA/pam_rhosts_auth.so.1
1067 rlogin auth required /usr/lib/security/$ISA/pam_unix.so.1 try_first_pass
1069 dtlogin auth sufficient /usr/lib/security/pam_winbind.so
1070 dtlogin auth required /usr/lib/security/$ISA/pam_unix.so.1 try_first_pass
1072 rsh auth required /usr/lib/security/$ISA/pam_rhosts_auth.so.1
1073 other auth sufficient /usr/lib/security/pam_winbind.so
1074 other auth required /usr/lib/security/$ISA/pam_unix.so.1 try_first_pass
1076 # Account management
1078 login account sufficient /usr/lib/security/pam_winbind.so
1079 login account requisite /usr/lib/security/$ISA/pam_roles.so.1
1080 login account required /usr/lib/security/$ISA/pam_unix.so.1
1082 dtlogin account sufficient /usr/lib/security/pam_winbind.so
1083 dtlogin account requisite /usr/lib/security/$ISA/pam_roles.so.1
1084 dtlogin account required /usr/lib/security/$ISA/pam_unix.so.1
1086 other account sufficient /usr/lib/security/pam_winbind.so
1087 other account requisite /usr/lib/security/$ISA/pam_roles.so.1
1088 other account required /usr/lib/security/$ISA/pam_unix.so.1
1090 # Session management
1092 other session required /usr/lib/security/$ISA/pam_unix.so.1
1094 # Password management
1096 #other password sufficient /usr/lib/security/pam_winbind.so
1097 other password required /usr/lib/security/$ISA/pam_unix.so.1
1098 dtsession auth required /usr/lib/security/$ISA/pam_unix.so.1
1100 # Support for Kerberos V5 authentication (uncomment to use Kerberos)
1102 #rlogin auth optional /usr/lib/security/$ISA/pam_krb5.so.1 try_first_pass
1103 #login auth optional /usr/lib/security/$ISA/pam_krb5.so.1 try_first_pass
1104 #dtlogin auth optional /usr/lib/security/$ISA/pam_krb5.so.1 try_first_pass
1105 #other auth optional /usr/lib/security/$ISA/pam_krb5.so.1 try_first_pass
1106 #dtlogin account optional /usr/lib/security/$ISA/pam_krb5.so.1
1107 #other account optional /usr/lib/security/$ISA/pam_krb5.so.1
1108 #other session optional /usr/lib/security/$ISA/pam_krb5.so.1
1109 #other password optional /usr/lib/security/$ISA/pam_krb5.so.1 try_first_pass
1110 </programlisting></para>
1113 I also added a <parameter>try_first_pass</parameter> line after the <filename>winbind.so</filename>
1114 line to get rid of annoying double prompts for passwords.
1118 Now restart your Samba and try connecting through your application that you
1119 configured in the pam.conf.
1131 <title>Conclusion</title>
1133 <para>The Winbind system, through the use of the Name Service
1134 Switch, Pluggable Authentication Modules, and appropriate
1135 Microsoft RPC calls have allowed us to provide seamless
1136 integration of Microsoft Windows NT domain users on a
1137 UNIX system. The result is a great reduction in the administrative
1138 cost of running a mixed UNIX and NT network.</para>
1143 <title>Common Errors</title>
1145 <para>Winbind has a number of limitations in its current
1146 released version that we hope to overcome in future
1150 <listitem><para>Winbind is currently only available for
1151 the Linux, Solaris, AIX, and IRIX operating systems, although ports to other operating
1152 systems are certainly possible. For such ports to be feasible,
1153 we require the C library of the target operating system to
1154 support the Name Service Switch and Pluggable Authentication
1155 Modules systems. This is becoming more common as NSS and
1156 PAM gain support among UNIX vendors.</para></listitem>
1158 <listitem><para>The mappings of Windows NT RIDs to UNIX IDs
1159 is not made algorithmically and depends on the order in which
1160 unmapped users or groups are seen by Winbind. It may be difficult
1161 to recover the mappings of RID to UNIX ID mapping if the file
1162 containing this information is corrupted or destroyed.</para>
1165 <listitem><para>Currently the Winbind PAM module does not take
1166 into account possible workstation and logon time restrictions
1167 that may be set for Windows NT users, this is
1168 instead up to the PDC to enforce.</para></listitem>
1172 <title>NSCD Problem Warning</title>
1174 <?latex \nopagebreak ?>
1177 Do not under any circumstances run <command>nscd</command> on any system
1178 on which <command>winbindd</command> is running.
1182 If <command>nscd</command> is running on the UNIX/Linux system, then
1183 even though NSSWITCH is correctly configured it will not be possible to resolve
1184 domain users and groups for file and directory controls.
1190 <title>Winbind Is Not Resolving Users and Groups</title>
1193 My &smb.conf; file is correctly configured. I have specified
1194 <smbconfoption><name>idmap uid</name><value>12000</value></smbconfoption>,
1195 and <smbconfoption><name>idmap gid</name><value>3000-3500</value></smbconfoption>
1196 and <command>winbind</command> is running. When I do the following it all works fine.
1200 &rootprompt;<userinput>wbinfo -u</userinput>
1207 &rootprompt;<userinput>wbinfo -g</userinput>
1208 MIDEARTH+Domain Users
1209 MIDEARTH+Domain Admins
1210 MIDEARTH+Domain Guests
1214 &rootprompt;<userinput>getent passwd</userinput>
1215 root:x:0:0:root:/root:/bin/bash
1216 bin:x:1:1:bin:/bin:/bin/bash
1218 maryo:x:15000:15003:Mary Orville:/home/MIDEARTH/maryo:/bin/false
1222 But the following command just fails:
1224 &rootprompt;<userinput>chown maryo a_file</userinput>
1225 chown: `maryo': invalid user
1227 This is driving me nuts! What can be wrong?
1231 Same problem as the one above.
1232 Your system is likely running <command>nscd</command>, the name service
1233 caching daemon. Shut it down, do not restart it! You will find your problem resolved.