source: clfs-sysroot/BOOK/final-system/common/shadow.xml @ 2270211

Last change on this file since 2270211 was 2270211, checked in by Joe Ciccone <jciccone@…>, 15 years ago

Update Patches in the book.
  • Property mode set to 100644
File size: 19.6 KB
Line 
1<?xml version="1.0" encoding="ISO-8859-1"?>
2<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
4  <!ENTITY % general-entities SYSTEM "../../general.ent">
5  %general-entities;
6]>
7
8<sect1 id="ch-system-shadow" role="wrap">
9  <?dbhtml filename="shadow.html"?>
10
11  <title>Shadow-&shadow-version;</title>
12
13  <indexterm zone="ch-system-shadow">
14    <primary sortas="a-Shadow">Shadow</primary>
15  </indexterm>
16
17  <sect2 role="package">
18    <title/>
19
20    <para>The Shadow package contains programs for handling passwords in a
21    secure way.</para>
22
23  </sect2>
24
25  <sect2 role="installation">
26    <title>Installation of Shadow</title>
27
28    <note os="a">
29      <para>If you would like to enforce the use of strong passwords,
30      refer to <ulink url="&blfs-root;view/svn/postlfs/cracklib.html"/>
31      for installing Cracklib prior to building Shadow. Then add
32      <parameter>--with-libcrack</parameter> to the <command>configure</command>
33      command below.</para>
34    </note>
35
36    <para os="b">Create a config.cache containing information about a test that
37    cannot be run when cross-compiling:</para>
38
39<screen os="c"><userinput>echo "ac_cv_func_setpgrp_void=yes" &gt; config.cache</userinput></screen>
40
41    <para os="d">Prepare Shadow for compilation:</para>
42
43<screen os="e"><userinput>./configure --build=${CLFS_HOST} --host=${CLFS_TARGET} \
44    --libdir=/lib --sysconfdir=/etc --enable-shared \
45    --without-libpam --without-audit --without-selinux \
46    --cache-file=config.cache</userinput></screen>
47
48<para os="f">The meaning of the configure options:</para>
49
50  <variablelist os="g">
51    <varlistentry>
52      <term><parameter>--sysconfdir=/etc</parameter></term>
53      <listitem><para>Tells Shadow to install its configuration files into
54      /etc, rather than /usr/etc.</para></listitem>
55    </varlistentry>
56    <varlistentry>
57      <term><parameter>--without-libpam</parameter></term>
58      <listitem><para>Support for Linux-PAM is enabled by default in Shadow,
59      however PAM is not installed on a base CLFS system, so this switch
60      disables PAM support in Shadow. For instructions to install PAM and
61      link Shadow to it, you can look at
62      <ulink url="&blfs-root;view/svn/postlfs/shadow.html"/>.</para></listitem>
63    </varlistentry>
64    <varlistentry>
65      <term><parameter>--without-audit</parameter></term>
66      <listitem><para>Support for auditing is enabled by default, but a
67      library that it needs is not installed in a base CLFS system. This
68      switch disables auditing support.</para></listitem>
69    </varlistentry>
70    <varlistentry>
71      <term><parameter>--without-selinux</parameter></term>
72      <listitem><para>Support for selinux is enabled by default, but selinux
73      is not built in a base CLFS system and configure will fail without this
74      switch.</para></listitem>
75    </varlistentry>
76  </variablelist>
77
78    <para os="h">Disable the installation of the <command>groups</command>
79    program and its man pages, as Coreutils provides a better version:</para>
80
81<screen os="i"><userinput>cp src/Makefile{,.orig}
82sed 's/groups$(EXEEXT) //' src/Makefile.orig &gt; src/Makefile
83cp man/Makefile{,.orig}
84sed -e '/groups1.xml/d' \
85    -e 's/groups.1//' man/Makefile.orig &gt; man/Makefile</userinput></screen>
86
87    <para os="j">Compile the package:</para>
88
89<screen os="k"><userinput>make</userinput></screen>
90
91    <para os="l">Install the package:</para>
92
93<screen os="m"><userinput>make DESTDIR=${CLFS} install</userinput></screen>
94
95    <para id="shadow-login_defs" os="r">Instead of using the default
96    <emphasis>crypt</emphasis> method, use the more secure
97    <emphasis>MD5</emphasis> method of password encryption, which also allows
98    passwords longer than 8 characters. It is also necessary to change the
99    obsolete <filename class="directory">/var/spool/mail</filename> location
100    for user mailboxes that Shadow uses by default to the <filename
101    class="directory">/var/mail</filename> location used currently. Use the
102    following sed command to make these changes to the appropriate
103    configuration file:</para>
104
105    <indexterm zone="shadow-login_defs" os="s">
106      <primary sortas="e-/etc/login.defs">/etc/login.defs</primary>
107    </indexterm>
108
109<screen os="t"><userinput>cp ${CLFS}/etc/login.defs login.defs.orig
110sed -e's@#MD5_CRYPT_ENAB.no@MD5_CRYPT_ENAB yes@' \
111    -e 's@/var/spool/mail@/var/mail@' \
112    login.defs.orig &gt; ${CLFS}/etc/login.defs</userinput></screen>
113
114    <note os="u">
115      <para>If you built Shadow with Cracklib support, execute
116      this <command>sed</command> to correct the path to the Cracklib
117      dictionary:</para>
118
119<screen role="nodump"><userinput>cp ${CLFS}/etc/login.defs login.defs.orig
120sed 's@DICTPATH.*@DICTPATH\t/lib/cracklib/pw_dict@' login.defs.orig \
121    &gt; ${CLFS}/etc/login.defs</userinput></screen>
122    </note>
123
124    <para os="v">Move a misplaced program to its proper location:</para>
125
126<screen os="w"><userinput>mv -v ${CLFS}/usr/bin/passwd ${CLFS}/bin</userinput></screen>
127
128    <para os="x">Move Shadow's static and dynamic libraries to a more
129    appropriate location:</para>
130
131<screen os="y"><userinput>mv -v ${CLFS}/lib/libshadow.*a ${CLFS}/usr/lib
132rm -v ${CLFS}/lib/libshadow.so
133ln -sfv ../../lib/libshadow.so.0 ${CLFS}/usr/lib/libshadow.so</userinput></screen>
134
135  </sect2>
136
137  <sect2 id="conf-shadow" role="configuration">
138    <title>Configuring Shadow</title>
139
140    <indexterm zone="conf-shadow">
141      <primary sortas="a-Shadow">Shadow</primary>
142      <secondary>configuring</secondary>
143    </indexterm>
144
145    <para>This package contains utilities to add, modify, and delete users and
146    groups; set and change their passwords; and perform other administrative
147    tasks. For a full explanation of what <emphasis>password shadowing</emphasis>
148    means, see the <filename>doc/HOWTO</filename> file within the unpacked source
149    tree. If using Shadow support, keep in mind that programs which need to
150    verify passwords (display managers, FTP programs, pop3 daemons, etc.) must
151    be Shadow-compliant. That is, they need to be able to work with shadowed
152    passwords.</para>
153
154    <para>To enable shadowed passwords, run the following command:</para>
155
156<screen role="nodump"><userinput>${CLFS_TARGET}-pwconv</userinput></screen>
157
158    <para>To enable shadowed group passwords, run:</para>
159
160<screen role="nodump"><userinput>${CLFS_TARGET}-grpconv</userinput></screen>
161
162    <para>To view or change the default settings for new user accounts that
163    you create, you can edit <filename>/etc/default/useradd</filename>. See
164    <command>man useradd</command> or
165    <ulink url="&blfs-root;view/svn/postlfs/skel.html"/> for more
166    information.</para>
167
168  </sect2>
169
170  <sect2 id="root-password" role="configuration">
171    <title>Setting the root password</title>
172
173    <para>Choose a password for user <systemitem
174    class="username">root</systemitem> and set it by running:</para>
175
176<screen role="nodump"><userinput>${CLFS_TARGET}-passwd root</userinput></screen>
177
178  </sect2>
179
180  <sect2 id="contents-shadow" role="content">
181    <title>Contents of Shadow</title>
182
183    <segmentedlist>
184      <segtitle>Installed programs</segtitle>
185      <segtitle>Installed libraries</segtitle>
186
187      <seglistitem>
188        <seg>chage, chfn, chpasswd, chgpasswd, chsh, expiry, faillog, gpasswd,
189        groupadd, groupdel, groupmod, grpck, grpconv, grpunconv, lastlog,
190        login, logoutd, newgrp, newusers, nologin, passwd, pwck, pwconv,
191        pwunconv, sg (link to newgrp), useradd, userdel, usermod,
192        vigr (link to vipw), and vipw</seg>
193        <seg>libshadow.[a,so]</seg>
194      </seglistitem>
195    </segmentedlist>
196
197    <variablelist>
198      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
199      <?dbfo list-presentation="list"?>
200      <?dbhtml list-presentation="table"?>
201
202      <varlistentry id="chage">
203        <term><command>chage</command></term>
204        <listitem>
205          <para>Used to change the maximum number of days between obligatory
206          password changes</para>
207          <indexterm zone="ch-system-shadow chage">
208            <primary sortas="b-chage">chage</primary>
209          </indexterm>
210        </listitem>
211      </varlistentry>
212
213      <varlistentry id="chfn">
214        <term><command>chfn</command></term>
215        <listitem>
216          <para>Used to change a user's full name and other information</para>
217          <indexterm zone="ch-system-shadow chfn">
218            <primary sortas="b-chfn">chfn</primary>
219          </indexterm>
220        </listitem>
221      </varlistentry>
222
223      <varlistentry id="chgpasswd">
224        <term><command>chgpasswd</command></term>
225        <listitem>
226          <para>Used to update group passwords in batch mode</para>
227          <indexterm zone="ch-system-shadow chgpasswd">
228            <primary sortas="b-chgpasswd">chgpasswd</primary>
229          </indexterm>
230        </listitem>
231      </varlistentry>
232
233      <varlistentry id="chpasswd">
234        <term><command>chpasswd</command></term>
235        <listitem>
236          <para>Used to update the passwords of an entire series of user
237          accounts</para>
238          <indexterm zone="ch-system-shadow chpasswd">
239            <primary sortas="b-chpasswd">chpasswd</primary>
240          </indexterm>
241        </listitem>
242      </varlistentry>
243
244      <varlistentry id="chsh">
245        <term><command>chsh</command></term>
246        <listitem>
247          <para>Used to change a user's default login shell</para>
248          <indexterm zone="ch-system-shadow chsh">
249            <primary sortas="b-chsh">chsh</primary>
250          </indexterm>
251        </listitem>
252      </varlistentry>
253
254      <varlistentry id="expiry">
255        <term><command>expiry</command></term>
256        <listitem>
257          <para>Checks and enforces the current password expiration policy</para>
258          <indexterm zone="ch-system-shadow expiry">
259            <primary sortas="b-expiry">expiry</primary>
260          </indexterm>
261        </listitem>
262      </varlistentry>
263
264      <varlistentry id="faillog">
265        <term><command>faillog</command></term>
266        <listitem>
267          <para>Is used to examine the log of login failures, to set a maximum
268          number of failures before an account is blocked, or to reset the
269          failure count</para>
270          <indexterm zone="ch-system-shadow faillog">
271            <primary sortas="b-faillog">faillog</primary>
272          </indexterm>
273        </listitem>
274      </varlistentry>
275
276      <varlistentry id="gpasswd">
277        <term><command>gpasswd</command></term>
278        <listitem>
279          <para>Is used to add and delete members and administrators to
280          groups</para>
281          <indexterm zone="ch-system-shadow gpasswd">
282            <primary sortas="b-gpasswd">gpasswd</primary>
283          </indexterm>
284        </listitem>
285      </varlistentry>
286
287      <varlistentry id="groupadd">
288        <term><command>groupadd</command></term>
289        <listitem>
290          <para>Creates a group with the given name</para>
291          <indexterm zone="ch-system-shadow groupadd">
292            <primary sortas="b-groupadd">groupadd</primary>
293          </indexterm>
294        </listitem>
295      </varlistentry>
296
297      <varlistentry id="groupdel">
298        <term><command>groupdel</command></term>
299        <listitem>
300          <para>Deletes the group with the given name</para>
301          <indexterm zone="ch-system-shadow groupdel">
302            <primary sortas="b-groupdel">groupdel</primary>
303          </indexterm>
304        </listitem>
305      </varlistentry>
306
307      <varlistentry id="groupmod">
308        <term><command>groupmod</command></term>
309        <listitem>
310          <para>Is used to modify the given group's name or GID</para>
311          <indexterm zone="ch-system-shadow groupmod">
312            <primary sortas="b-groupmod">groupmod</primary>
313          </indexterm>
314        </listitem>
315      </varlistentry>
316
317      <varlistentry id="grpck">
318        <term><command>grpck</command></term>
319        <listitem>
320          <para>Verifies the integrity of the group files
321          <filename>/etc/group</filename> and
322          <filename>/etc/gshadow</filename></para>
323          <indexterm zone="ch-system-shadow grpck">
324            <primary sortas="b-grpck">grpck</primary>
325          </indexterm>
326        </listitem>
327      </varlistentry>
328
329      <varlistentry id="grpconv">
330        <term><command>grpconv</command></term>
331        <listitem>
332          <para>Creates or updates the shadow group file from the normal
333          group file</para>
334          <indexterm zone="ch-system-shadow grpconv">
335            <primary sortas="b-grpconv">grpconv</primary>
336          </indexterm>
337        </listitem>
338      </varlistentry>
339
340      <varlistentry id="grpunconv">
341        <term><command>grpunconv</command></term>
342        <listitem>
343          <para>Updates <filename>/etc/group</filename> from
344          <filename>/etc/gshadow</filename> and then deletes the latter</para>
345          <indexterm zone="ch-system-shadow grpunconv">
346            <primary sortas="b-grpunconv">grpunconv</primary>
347          </indexterm>
348        </listitem>
349      </varlistentry>
350
351      <varlistentry id="lastlog">
352        <term><command>lastlog</command></term>
353        <listitem>
354          <para>Reports the most recent login of all users or of a
355          given user</para>
356          <indexterm zone="ch-system-shadow lastlog">
357            <primary sortas="b-lastlog">lastlog</primary>
358          </indexterm>
359        </listitem>
360      </varlistentry>
361
362      <varlistentry id="login">
363        <term><command>login</command></term>
364        <listitem>
365          <para>Is used by the system to let users sign on</para>
366          <indexterm zone="ch-system-shadow login">
367            <primary sortas="b-login">login</primary>
368          </indexterm>
369        </listitem>
370      </varlistentry>
371
372      <varlistentry id="logoutd">
373        <term><command>logoutd</command></term>
374        <listitem>
375          <para>Is a daemon used to enforce restrictions on log-on time
376          and ports</para>
377          <indexterm zone="ch-system-shadow logoutd">
378            <primary sortas="b-logoutd">logoutd</primary>
379          </indexterm>
380        </listitem>
381      </varlistentry>
382
383      <varlistentry id="newgrp">
384        <term><command>newgrp</command></term>
385        <listitem>
386          <para>Is used to change the current GID during a login session</para>
387          <indexterm zone="ch-system-shadow newgrp">
388            <primary sortas="b-newgrp">newgrp</primary>
389          </indexterm>
390        </listitem>
391      </varlistentry>
392
393      <varlistentry id="newusers">
394        <term><command>newusers</command></term>
395        <listitem>
396          <para>Is used to create or update an entire series of user
397          accounts</para>
398          <indexterm zone="ch-system-shadow newusers">
399            <primary sortas="b-newusers">newusers</primary>
400          </indexterm>
401        </listitem>
402      </varlistentry>
403
404      <varlistentry id="nologin">
405        <term><command>nologin</command></term>
406        <listitem>
407          <para>Displays a message that an account is not available. Designed
408          to be used as the default shell for accounts that have been
409          disabled</para>
410          <indexterm zone="ch-system-shadow nologin">
411            <primary sortas="b-nologin">nologin</primary>
412          </indexterm>
413        </listitem>
414      </varlistentry>
415
416      <varlistentry id="passwd">
417        <term><command>passwd</command></term>
418        <listitem>
419          <para>Is used to change the password for a user or group account</para>
420          <indexterm zone="ch-system-shadow passwd">
421            <primary sortas="b-passwd">passwd</primary>
422          </indexterm>
423        </listitem>
424      </varlistentry>
425
426      <varlistentry id="pwck">
427        <term><command>pwck</command></term>
428        <listitem>
429          <para>Verifies the integrity of the password files
430          <filename>/etc/passwd</filename> and
431          <filename>/etc/shadow</filename></para>
432          <indexterm zone="ch-system-shadow pwck">
433            <primary sortas="b-pwck">pwck</primary>
434          </indexterm>
435        </listitem>
436      </varlistentry>
437
438      <varlistentry id="pwconv">
439        <term><command>pwconv</command></term>
440        <listitem>
441          <para>Creates or updates the shadow password file from the normal
442          password file</para>
443          <indexterm zone="ch-system-shadow pwconv">
444            <primary sortas="b-pwconv">pwconv</primary>
445          </indexterm>
446        </listitem>
447      </varlistentry>
448
449      <varlistentry id="pwunconv">
450        <term><command>pwunconv</command></term>
451        <listitem>
452          <para>Updates <filename>/etc/passwd</filename> from
453          <filename>/etc/shadow</filename> and then deletes the latter</para>
454          <indexterm zone="ch-system-shadow pwunconv">
455            <primary sortas="b-pwunconv">pwunconv</primary>
456          </indexterm>
457        </listitem>
458      </varlistentry>
459
460      <varlistentry id="sg">
461        <term><command>sg</command></term>
462        <listitem>
463          <para>Executes a given command while the user's GID
464          is set to that of the given group</para>
465          <indexterm zone="ch-system-shadow sg">
466            <primary sortas="b-sg">sg</primary>
467          </indexterm>
468        </listitem>
469      </varlistentry>
470
471      <varlistentry id="su">
472        <term><command>su</command></term>
473        <listitem>
474          <para>Runs a shell with substitute user and group IDs</para>
475          <indexterm zone="ch-system-shadow su">
476            <primary sortas="b-su">su</primary>
477          </indexterm>
478        </listitem>
479      </varlistentry>
480
481      <varlistentry id="useradd">
482        <term><command>useradd</command></term>
483        <listitem>
484          <para>Creates a new user with the given name, or updates the default
485          new-user information</para>
486          <indexterm zone="ch-system-shadow useradd">
487            <primary sortas="b-useradd">useradd</primary>
488          </indexterm>
489        </listitem>
490      </varlistentry>
491
492      <varlistentry id="userdel">
493        <term><command>userdel</command></term>
494        <listitem>
495          <para>Deletes the given user account</para>
496          <indexterm zone="ch-system-shadow userdel">
497            <primary sortas="b-userdel">userdel</primary>
498          </indexterm>
499        </listitem>
500      </varlistentry>
501
502      <varlistentry id="usermod">
503        <term><command>usermod</command></term>
504        <listitem>
505          <para>Is used to modify the given user's login name, User
506          Identification (UID), shell, initial group, home directory, etc.</para>
507          <indexterm zone="ch-system-shadow usermod">
508            <primary sortas="b-usermod">usermod</primary>
509          </indexterm>
510        </listitem>
511      </varlistentry>
512
513      <varlistentry id="vigr">
514        <term><command>vigr</command></term>
515        <listitem>
516          <para>Edits the <filename>/etc/group</filename> or
517          <filename>/etc/gshadow</filename> files</para>
518          <indexterm zone="ch-system-shadow vigr">
519            <primary sortas="b-vigr">vigr</primary>
520          </indexterm>
521        </listitem>
522      </varlistentry>
523
524      <varlistentry id="vipw">
525        <term><command>vipw</command></term>
526        <listitem>
527          <para>Edits the <filename>/etc/passwd</filename> or
528          <filename>/etc/shadow</filename> files</para>
529          <indexterm zone="ch-system-shadow vipw">
530            <primary sortas="b-vipw">vipw</primary>
531          </indexterm>
532        </listitem>
533      </varlistentry>
534
535      <varlistentry id="libshadow">
536        <term><filename class="libraryfile">libshadow</filename></term>
537        <listitem>
538          <para>Contains functions used by most programs in this package</para>
539          <indexterm zone="ch-system-shadow libshadow">
540            <primary sortas="c-libshadow">libshadow</primary>
541          </indexterm>
542        </listitem>
543      </varlistentry>
544
545    </variablelist>
546
547  </sect2>
548
549</sect1>
Note: See TracBrowser for help on using the repository browser.