docs/docbook/manpages/winbindd.8.sgml

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   4 <refentry id="winbindd.8">
   5
   6 <refmeta>
   7         <refentrytitle>winbindd</refentrytitle>
   8         <manvolnum>8</manvolnum>
   9 </refmeta>
  10
  11
  12 <refnamediv>
  13         <refname>winbindd</refname>
  14         <refpurpose>Name Service Switch daemon for resolving names
  15         from NT servers</refpurpose>
  16 </refnamediv>
  17
  18 <refsynopsisdiv>
  19         <cmdsynopsis>
  20                 <command>winbindd</command>
  21                 <arg choice="opt">-F</arg>
  22                 <arg choice="opt">-S</arg>
  23                 <arg choice="opt">-i</arg>
  24                 <arg choice="opt">-B</arg>
  25                 <arg choice="opt">-d &lt;debug level&gt;</arg>
  26                 <arg choice="opt">-s &lt;smb config file&gt;</arg>
  27                 <arg choice="opt">-n</arg>
  28         </cmdsynopsis>
  29 </refsynopsisdiv>
  30
  31 <refsect1>
  32         <title>DESCRIPTION</title>
  33
  34         <para>This program is part of the <citerefentry><refentrytitle>Samba</refentrytitle>
  35         <manvolnum>7</manvolnum></citerefentry> suite.</para>
  36
  37         <para><command>winbindd</command> is a daemon that provides
  38         a service for the Name Service Switch capability that is present
  39         in most modern C libraries.  The Name Service Switch allows user
  40         and system information to be obtained from different databases
  41         services such as NIS or DNS.  The exact behaviour can be configured
  42         throught the <filename>/etc/nsswitch.conf</filename> file.
  43         Users and groups are allocated as they are resolved to a range
  44         of user and group ids specified by the administrator of the
  45         Samba system.</para>
  46
  47         <para>The service provided by <command>winbindd</command> is called `winbind' and
  48         can be used to resolve user and group information from a
  49         Windows NT server. The service can also provide authentication
  50         services via an associated PAM module. </para>
  51
  52         <para>
  53         The <filename>pam_winbind</filename> module in the 2.2.2 release only
  54         supports the <parameter>auth</parameter> and <parameter>account</parameter>
  55         module-types.  The latter simply
  56         performs a getpwnam() to verify that the system can obtain a uid for the
  57         user.  If the <filename>libnss_winbind</filename> library has been correctly
  58         installed, this should always succeed.
  59         </para>
  60
  61         <para>The following nsswitch databases are implemented by
  62         the winbindd service: </para>
  63
  64         <variablelist>
  65                 <varlistentry>
  66                 <term>hosts</term>
  67                 <listitem><para>User information traditionally stored in
  68                 the <filename>hosts(5)</filename> file and used by
  69                 <command>gethostbyname(3)</command> functions. Names are
  70                 resolved through the WINS server or by broadcast.
  71                 </para></listitem>
  72                 </varlistentry>
  73
  74                 <varlistentry>
  75                 <term>passwd</term>
  76                 <listitem><para>User information traditionally stored in
  77                 the <filename>passwd(5)</filename> file and used by
  78                 <command>getpwent(3)</command> functions. </para></listitem>
  79                 </varlistentry>
  80
  81                 <varlistentry>
  82                 <term>group</term>
  83                 <listitem><para>Group information traditionally stored in
  84                 the <filename>group(5)</filename> file and used by
  85                 <command>getgrent(3)</command> functions. </para></listitem>
  86                 </varlistentry>
  87         </variablelist>
  88
  89         <para>For example, the following simple configuration in the
  90         <filename>/etc/nsswitch.conf</filename> file can be used to initially
  91         resolve user and group information from <filename>/etc/passwd
  92         </filename> and <filename>/etc/group</filename> and then from the
  93         Windows NT server.
  94 <programlisting>
  95 passwd:         files winbind
  96 group:          files winbind
  97 </programlisting></para>
  98
  99         <para>The following simple configuration in the
 100         <filename>/etc/nsswitch.conf</filename> file can be used to initially
 101         resolve hostnames from <filename>/etc/hosts</filename> and then from the
 102         WINS server.</para>
 103
 104 </refsect1>
 105
 106
 107 <refsect1>
 108         <title>OPTIONS</title>
 109
 110         <variablelist>
 111                 <varlistentry>
 112                 <term>-F</term>
 113                 <listitem><para>If specified, this parameter causes
 114                 the main <command>winbindd</command> process to not daemonize,
 115                 i.e. double-fork and disassociate with the terminal.
 116                 Child processes are still created as normal to service
 117                 each connection request, but the main process does not
 118                 exit. This operation mode is suitable for running
 119                 <command>winbindd</command> under process supervisors such
 120                 as <command>supervise</command> and <command>svscan</command>
 121                 from Daniel J. Bernstein's <command>daemontools</command>
 122                 package, or the AIX process monitor.
 123                 </para></listitem>
 124                 </varlistentry>
 125
 126                 <varlistentry>
 127                 <term>-S</term>
 128                 <listitem><para>If specified, this parameter causes
 129                 <command>winbindd</command> to log to standard output rather
 130                 than a file.</para></listitem>
 131                 </varlistentry>
 132
 133                 &popt.common.samba;
 134                 &stdarg.help;
 135
 136                 <varlistentry>
 137                 <term>-i</term>
 138                 <listitem><para>Tells <command>winbindd</command> to not
 139                 become a daemon and detach from the current terminal. This
 140                 option is used by developers when interactive debugging
 141                 of <command>winbindd</command> is required.
 142                 <command>winbindd</command> also logs to standard output,
 143                 as if the <command>-S</command> parameter had been given.
 144                 </para></listitem>
 145                 </varlistentry>
 146
 147                 <varlistentry>
 148                 <term>-n</term>
 149                 <listitem><para>Disable caching. This means winbindd will
 150                 always have to wait for a response from the domain controller
 151                 before it can respond to a client and this thus makes things
 152                 slower. The results will however be more accurate, since
 153                 results from the cache might not be up-to-date. This
 154                 might also temporarily hang winbindd if the DC doesn't respond.
 155                 </para></listitem>
 156                 </varlistentry>
 157
 158                 <varlistentry>
 159                 <term>-B</term>
 160                 <listitem><para>Dual daemon mode. This means winbindd will run
 161                 as 2 threads. The first will answer all requests from the cache,
 162                 thus making responses to clients faster. The other will
 163                 update the cache for the query that the first has just responded.
 164                 Advantage of this is that responses stay accurate and are faster.
 165                 </para></listitem>
 166                 </varlistentry>
 167
 168         </variablelist>
 169 </refsect1>
 170
 171
 172 <refsect1>
 173         <title>NAME AND ID RESOLUTION</title>
 174
 175         <para>Users and groups on a Windows NT server are assigned
 176         a relative id (rid) which is unique for the domain when the
 177         user or group is created.  To convert the Windows NT user or group
 178         into a unix user or group, a mapping between rids and unix user
 179         and group ids is required.  This is one of the jobs that <command>
 180         winbindd</command> performs. </para>
 181
 182         <para>As winbindd users and groups are resolved from a server, user
 183         and group ids are allocated from a specified range.  This
 184         is done on a first come, first served basis, although all existing
 185         users and groups will be mapped as soon as a client performs a user
 186         or group enumeration command.  The allocated unix ids are stored
 187         in a database file under the Samba lock directory and will be
 188         remembered. </para>
 189
 190         <para>WARNING: The rid to unix id database is the only location
 191         where the user and group mappings are stored by winbindd.  If this
 192         file is deleted or corrupted, there is no way for winbindd to
 193         determine which user and group ids correspond to Windows NT user
 194         and group rids. </para>
 195 </refsect1>
 196
 197
 198 <refsect1>
 199         <title>CONFIGURATION</title>
 200
 201         <para>Configuration of the <command>winbindd</command> daemon
 202         is done through configuration parameters in the <citerefentry>
 203         <refentrytitle>smb.conf</refentrytitle><manvolnum>5</manvolnum>
 204         </citerefentry> file.  All parameters should be specified in the
 205         [global] section of smb.conf. </para>
 206
 207         <itemizedlist>
 208                 <listitem><para><ulink url="smb.conf.5.html#WINBINDSEPARATOR">
 209                 <parameter>winbind separator</parameter></ulink></para></listitem>
 210                 <listitem><para><ulink url="smb.conf.5.html#WINBINDUID">
 211                 <parameter>winbind uid</parameter></ulink></para></listitem>
 212                 <listitem><para><ulink url="smb.conf.5.html#WINBINDGID">
 213                 <parameter>winbind gid</parameter></ulink></para></listitem>
 214                 <listitem><para><ulink url="smb.conf.5.html#WINBINDCACHETIME">
 215                 <parameter>winbind cache time</parameter></ulink></para></listitem>
 216                 <listitem><para><ulink url="smb.conf.5.html#WINBINDENUMUSERS">
 217                 <parameter>winbind enum users</parameter></ulink></para></listitem>
 218                 <listitem><para><ulink url="smb.conf.5.html#WINBINDENUMGROUPS">
 219                 <parameter>winbind enum groups</parameter></ulink></para></listitem>
 220                 <listitem><para><ulink url="smb.conf.5.html#TEMPLATEHOMEDIR">
 221                 <parameter>template homedir</parameter></ulink></para></listitem>
 222                 <listitem><para><ulink url="smb.conf.5.html#TEMPLATESHELL">
 223                 <parameter>template shell</parameter></ulink></para></listitem>
 224                 <listitem><para><ulink url="smb.conf.5.html#WINBINDUSEDEFAULTDOMAIN">
 225                 <parameter>winbind use default domain</parameter></ulink></para></listitem>
 226         </itemizedlist>
 227 </refsect1>
 228
 229
 230 <refsect1>
 231         <title>EXAMPLE SETUP</title>
 232
 233         <para>To setup winbindd for user and group lookups plus
 234         authentication from a domain controller use something like the
 235         following setup. This was tested on a RedHat 6.2 Linux box. </para>
 236
 237         <para>In <filename>/etc/nsswitch.conf</filename> put the
 238         following:
 239 <programlisting>
 240 passwd:     files winbind
 241 group:      files winbind
 242 </programlisting></para>
 243
 244         <para>In <filename>/etc/pam.d/*</filename> replace the <parameter>
 245         auth</parameter> lines with something like this:
 246 <programlisting>
 247 auth       required     /lib/security/pam_securetty.so
 248 auth       required     /lib/security/pam_nologin.so
 249 auth       sufficient   /lib/security/pam_winbind.so
 250 auth       required     /lib/security/pam_pwdb.so use_first_pass shadow nullok
 251 </programlisting></para>
 252
 253
 254         <para>Note in particular the use of the <parameter>sufficient
 255         </parameter> keyword and the <parameter>use_first_pass</parameter> keyword. </para>
 256
 257         <para>Now replace the account lines with this: </para>
 258
 259         <para><command>account    required      /lib/security/pam_winbind.so
 260         </command></para>
 261
 262         <para>The next step is to join the domain. To do that use the
 263         <command>net</command> program like this:  </para>
 264
 265         <para><command>net join -S PDC -U Administrator</command></para>
 266
 267         <para>The username after the <parameter>-U</parameter> can be any
 268         Domain user that has administrator privileges on the machine.
 269         Substitute the name or IP of your PDC for "PDC".</para>
 270
 271         <para>Next copy <filename>libnss_winbind.so</filename> to
 272         <filename>/lib</filename> and <filename>pam_winbind.so
 273         </filename> to <filename>/lib/security</filename>.  A symbolic link needs to be
 274         made from <filename>/lib/libnss_winbind.so</filename> to
 275         <filename>/lib/libnss_winbind.so.2</filename>.  If you are using an
 276         older version of glibc then the target of the link should be
 277         <filename>/lib/libnss_winbind.so.1</filename>.</para>
 278
 279         <para>Finally, setup a <citerefentry><refentrytitle>smb.conf</refentrytitle>
 280         <manvolnum>5</manvolnum></citerefentry> containing directives like the
 281         following:
 282 <programlisting>
 283 [global]
 284         winbind separator = +
 285         winbind cache time = 10
 286         template shell = /bin/bash
 287         template homedir = /home/%D/%U
 288         winbind uid = 10000-20000
 289         winbind gid = 10000-20000
 290         workgroup = DOMAIN
 291         security = domain
 292         password server = *
 293 </programlisting></para>
 294
 295
 296         <para>Now start winbindd and you should find that your user and
 297         group database is expanded to include your NT users and groups,
 298         and that you can login to your unix box as a domain user, using
 299         the DOMAIN+user syntax for the username. You may wish to use the
 300         commands <command>getent passwd</command> and <command>getent group
 301         </command> to confirm the correct operation of winbindd.</para>
 302 </refsect1>
 303
 304
 305 <refsect1>
 306         <title>NOTES</title>
 307
 308         <para>The following notes are useful when configuring and
 309         running <command>winbindd</command>: </para>
 310
 311         <para><citerefentry><refentrytitle>nmbd</refentrytitle>
 312         <manvolnum>8</manvolnum></citerefentry> must be running on the local machine
 313         for <command>winbindd</command> to work. <command>winbindd</command> queries
 314         the list of trusted domains for the Windows NT server
 315         on startup and when a SIGHUP is received.  Thus, for a running <command>
 316         winbindd</command> to become aware of new trust relationships between
 317         servers, it must be sent a SIGHUP signal. </para>
 318
 319         <para>PAM is really easy to misconfigure.  Make sure you know what
 320         you are doing when modifying PAM configuration files.  It is possible
 321         to set up PAM such that you can no longer log into your system. </para>
 322
 323         <para>If more than one UNIX machine is running <command>winbindd</command>,
 324         then in general the user and groups ids allocated by winbindd will not
 325         be the same.  The user and group ids will only be valid for the local
 326         machine.</para>
 327
 328         <para>If the the Windows NT RID to UNIX user and group id mapping
 329         file is damaged or destroyed then the mappings will be lost. </para>
 330 </refsect1>
 331
 332
 333 <refsect1>
 334         <title>SIGNALS</title>
 335
 336         <para>The following signals can be used to manipulate the
 337         <command>winbindd</command> daemon. </para>
 338
 339         <variablelist>
 340                 <varlistentry>
 341                 <term>SIGHUP</term>
 342                 <listitem><para>Reload the <citerefentry><refentrytitle>smb.conf</refentrytitle>
 343                 <manvolnum>5</manvolnum></citerefentry> file and
 344                 apply any parameter changes to the running
 345                 version of winbindd.  This signal also clears any cached
 346                 user and group information.  The list of other domains trusted
 347                 by winbindd is also reloaded.  </para></listitem>
 348                 </varlistentry>
 349
 350                 <varlistentry>
 351                 <term>SIGUSR1</term>
 352                 <listitem><para>The SIGUSR1 signal will cause <command>
 353                 winbindd</command> to write status information to the winbind
 354                 log file including information about the number of user and
 355                 group ids allocated by <command>winbindd</command>.</para>
 356
 357                 <para>Log files are stored in the filename specified by the
 358                 log file parameter.</para></listitem>
 359                 </varlistentry>
 360         </variablelist>
 361 </refsect1>
 362
 363 <refsect1>
 364         <title>FILES</title>
 365
 366         <variablelist>
 367                 <varlistentry>
 368                 <term><filename>/etc/nsswitch.conf(5)</filename></term>
 369                 <listitem><para>Name service switch configuration file.</para>
 370                 </listitem>
 371                 </varlistentry>
 372
 373                 <varlistentry>
 374                 <term>/tmp/.winbindd/pipe</term>
 375                 <listitem><para>The UNIX pipe over which clients communicate with
 376                 the <command>winbindd</command> program.  For security reasons, the
 377                 winbind client will only attempt to connect to the winbindd daemon
 378                 if both the <filename>/tmp/.winbindd</filename> directory
 379                 and <filename>/tmp/.winbindd/pipe</filename> file are owned by
 380                 root. </para></listitem>
 381                 </varlistentry>
 382
 383                 <varlistentry>
 384                 <term>$LOCKDIR/winbindd_privilaged/pipe</term>
 385                 <listitem><para>The UNIX pipe over which 'privilaged' clients
 386                 communicate with the <command>winbindd</command> program.  For security
 387                 reasons, access to some winbindd functions - like those needed by
 388                 the <command>ntlm_auth</command> utility - is restricted.  By default,
 389                 only users in the 'root' group will get this access, however the administrator
 390                 may change the group permissions on $LOCKDIR/winbindd_privilaged to allow
 391                 programs like 'squid' to use ntlm_auth.
 392                 Note that the winbind client will only attempt to connect to the winbindd daemon
 393                 if both the <filename>$LOCKDIR/winbindd_privilaged</filename> directory
 394                 and <filename>$LOCKDIR/winbindd_privilaged/pipe</filename> file are owned by
 395                 root. </para></listitem>
 396                 </varlistentry>
 397
 398                 <varlistentry>
 399                 <term>/lib/libnss_winbind.so.X</term>
 400                 <listitem><para>Implementation of name service switch library.
 401                 </para></listitem>
 402                 </varlistentry>
 403
 404                 <varlistentry>
 405                 <term>$LOCKDIR/winbindd_idmap.tdb</term>
 406                 <listitem><para>Storage for the Windows NT rid to UNIX user/group
 407                 id mapping.  The lock directory is specified when Samba is initially
 408                 compiled using the <parameter>--with-lockdir</parameter> option.
 409                 This directory is by default <filename>/usr/local/samba/var/locks
 410                 </filename>. </para></listitem>
 411                 </varlistentry>
 412
 413                 <varlistentry>
 414                 <term>$LOCKDIR/winbindd_cache.tdb</term>
 415                 <listitem><para>Storage for cached user and group information.
 416                 </para></listitem>
 417                 </varlistentry>
 418         </variablelist>
 419 </refsect1>
 420
 421
 422 <refsect1>
 423         <title>VERSION</title>
 424
 425         <para>This man page is correct for version 3.0 of
 426         the Samba suite.</para>
 427 </refsect1>
 428
 429 <refsect1>
 430         <title>SEE ALSO</title>
 431
 432         <para><filename>nsswitch.conf(5)</filename>, <citerefentry>
 433         <refentrytitle>Samba</refentrytitle>
 434         <manvolnum>7</manvolnum></citerefentry>, <citerefentry>
 435         <refentrytitle>wbinfo</refentrytitle>
 436         <manvolnum>8</manvolnum></citerefentry>, <citerefentry>
 437         <refentrytitle>smb.conf</refentrytitle>
 438         <manvolnum>5</manvolnum></citerefentry></para>
 439 </refsect1>
 440
 441 <refsect1>
 442         <title>AUTHOR</title>
 443
 444         <para>The original Samba software and related utilities
 445         were created by Andrew Tridgell. Samba is now developed
 446         by the Samba Team as an Open Source project similar
 447         to the way the Linux kernel is developed.</para>
 448
 449         <para><command>wbinfo</command> and <command>winbindd</command> were
 450         written by Tim Potter.</para>
 451
 452         <para>The conversion to DocBook for Samba 2.2 was done
 453         by Gerald Carter. The conversion to DocBook XML 4.2 for
 454         Samba 3.0 was done by Alexander Bokovoy.</para>
 455 </refsect1>
 456
 457 </refentry>