source: clfs-sysroot/BOOK/final-system/common/shadow.xml @ 6c341df

Last change on this file since 6c341df was 6c341df, checked in by Jim Gifford <clfs@…>, 13 years ago

r3927@server (orig r1766): jciccone | 2006-06-14 15:29:43 -0700
Fixed a typo in the shadow instructions.

  • Property mode set to 100644
File size: 19.2 KB
Line 
1<?xml version="1.0" encoding="ISO-8859-1"?>
2<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
3  "http://www.oasis-open.org/docbook/xml/4.4/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 --libdir=/lib --sysconfdir=/etc --enable-shared \
44    --without-libpam --without-audit --without-selinux \
45    --host=${LFS_TARGET} --cache-file=config.cache</userinput></screen>
46
47<para os="f">The meaning of the configure options:</para>
48
49  <variablelist os="g">
50    <varlistentry>
51      <term><parameter>--without-libpam</parameter></term>
52      <listitem><para>Support for Linux-PAM is enabled by default in Shadow,
53      however PAM is not installed on a base LFS system, so this switch
54      disables PAM support in Shadow. For instructions to install PAM and
55      link Shadow to it, you can look at
56      <ulink url="&blfs-root;view/svn/postlfs/shadow.html"/>.</para></listitem>
57    </varlistentry>
58    <varlistentry>
59      <term><parameter>--without-audit</parameter></term>
60      <listitem><para>Support for auditing is enabled by default, but a
61      library that it needs is not installed in a base LFS system. This
62      switch disables auditing support.</para></listitem>
63    </varlistentry>
64    <varlistentry>
65      <term><parameter>--without-selinux</parameter></term>
66      <listitem><para>Support for selinux is enabled by default, but selinux
67      is not built in a base LFS system and configure will fail without this
68      switch.</para></listitem>
69    </varlistentry>
70  </variablelist>
71
72    <para os="h">Disable the installation of the <command>groups</command>
73    program and its man pages, as Coreutils provides a better version:</para>
74
75<screen os="i"><userinput>cp src/Makefile{,.orig}
76sed 's/groups$(EXEEXT) //' src/Makefile.orig &gt; src/Makefile
77cp man/Makefile{,.orig}
78sed '/groups/d' man/Makefile.orig &gt; man/Makefile</userinput></screen>
79
80    <para os="j">Compile the package:</para>
81
82<screen os="k"><userinput>make</userinput></screen>
83
84    <para os="l">Install the package:</para>
85
86<screen os="m"><userinput>make DESTDIR=${LFS} install</userinput></screen>
87
88    <para id="shadow-login_defs" os="r">Instead of using the default
89    <emphasis>crypt</emphasis> method, use the more secure
90    <emphasis>MD5</emphasis> method of password encryption, which also allows
91    passwords longer than 8 characters. It is also necessary to change the
92    obsolete <filename class="directory">/var/spool/mail</filename> location
93    for user mailboxes that Shadow uses by default to the <filename
94    class="directory">/var/mail</filename> location used currently. Both of
95    these can be accomplished by changing the relevant configuration file
96    while copying it to its destination:</para>
97
98    <indexterm zone="shadow-login_defs" os="s">
99      <primary sortas="e-/etc/login.defs">/etc/login.defs</primary>
100    </indexterm>
101
102<screen os="t"><userinput>cp ${LFS}/etc/login.defs login.defs.orig
103sed -e's@#MD5_CRYPT_ENAB.no@MD5_CRYPT_ENAB yes@' \
104    -e 's@/var/spool/mail@/var/mail@' \
105    login.defs.orig &gt; ${LFS}/etc/login.defs</userinput></screen>
106
107    <note os="u">
108      <para>If you built Shadow with Cracklib support, execute
109      this <command>sed</command> to correct the path to the Cracklib
110      dictionary:</para>
111
112<screen><userinput>cp {LFS}/etc/login.defs login.defs.orig
113sed 's@DICTPATH.*@DICTPATH\t/lib/cracklib/pw_dict@' login.defs.orig &gt; ${LFS}/etc/login.defs</userinput></screen>
114    </note>
115
116    <para os="v">Move a misplaced program to its proper location:</para>
117
118<screen os="w"><userinput>mv -v ${LFS}/usr/bin/passwd ${LFS}/bin</userinput></screen>
119
120    <para os="x">Move Shadow's dynamic libraries to a more appropriate
121    location:</para>
122
123<screen os="y"><userinput>mv -v ${LFS}/lib/libshadow.*a ${LFS}/usr/lib
124rm -v ${LFS}/lib/libshadow.so
125ln -svf ../../lib/libshadow.so.0 ${LFS}/usr/lib/libshadow.so</userinput></screen>
126
127    <para os="z">The <option>-D</option> option of the <command>useradd</command>
128    program requires the <filename class="directory">/etc/default</filename>
129    directory for it to work properly:</para>
130
131<screen os="za"><userinput>install -dv ${LFS}/etc/default</userinput></screen>
132
133  </sect2>
134
135  <sect2 id="conf-shadow" role="configuration">
136    <title>Configuring Shadow</title>
137
138    <indexterm zone="conf-shadow">
139      <primary sortas="a-Shadow">Shadow</primary>
140      <secondary>configuring</secondary>
141    </indexterm>
142
143    <para>This package contains utilities to add, modify, and delete users and
144    groups; set and change their passwords; and perform other administrative
145    tasks. For a full explanation of what <emphasis>password shadowing</emphasis>
146    means, see the <filename>doc/HOWTO</filename> file within the unpacked source
147    tree. If using Shadow support, keep in mind that programs which need to
148    verify passwords (display managers, FTP programs, pop3 daemons, etc.) must
149    be Shadow-compliant. That is, they need to be able to work with shadowed
150    passwords.</para>
151
152    <para>To enable shadowed passwords, run the following command:</para>
153
154<screen><userinput>pwconv</userinput></screen>
155
156    <para>To enable shadowed group passwords, run:</para>
157
158<screen role="nodump"><userinput>grpconv</userinput></screen>
159
160  </sect2>
161
162  <sect2 id="root-password" role="configuration">
163    <title>Setting the root password</title>
164
165    <para>Choose a password for user <systemitem
166    class="username">root</systemitem> and set it by running:</para>
167
168<screen role="nodump"><userinput>passwd root</userinput></screen>
169
170  </sect2>
171
172  <sect2 id="contents-shadow" role="content">
173    <title>Contents of Shadow</title>
174
175    <segmentedlist>
176      <segtitle>Installed programs</segtitle>
177      <segtitle>Installed libraries</segtitle>
178
179      <seglistitem>
180        <seg>chage, chfn, chpasswd, chgpasswd, chsh, expiry, faillog, gpasswd,
181        groupadd, groupdel, groupmod, grpck, grpconv, grpunconv, lastlog,
182        login, logoutd, newgrp, newusers, nologin, passwd, pwck, pwconv,
183        pwunconv, sg (link to newgrp), useradd, userdel, usermod,
184        vigr (link to vipw), and vipw</seg>
185        <seg>libshadow.[a,so]</seg>
186      </seglistitem>
187    </segmentedlist>
188
189    <variablelist>
190      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
191      <?dbfo list-presentation="list"?>
192      <?dbhtml list-presentation="table"?>
193
194      <varlistentry id="chage">
195        <term><command>chage</command></term>
196        <listitem>
197          <para>Used to change the maximum number of days between obligatory
198          password changes</para>
199          <indexterm zone="ch-system-shadow chage">
200            <primary sortas="b-chage">chage</primary>
201          </indexterm>
202        </listitem>
203      </varlistentry>
204
205      <varlistentry id="chfn">
206        <term><command>chfn</command></term>
207        <listitem>
208          <para>Used to change a user's full name and other information</para>
209          <indexterm zone="ch-system-shadow chfn">
210            <primary sortas="b-chfn">chfn</primary>
211          </indexterm>
212        </listitem>
213      </varlistentry>
214
215      <varlistentry id="chgpasswd">
216        <term><command>chgpasswd</command></term>
217        <listitem>
218          <para>Used to update group passwords in batch mode</para>
219          <indexterm zone="ch-system-shadow chgpasswd">
220            <primary sortas="b-chgpasswd">chgpasswd</primary>
221          </indexterm>
222        </listitem>
223      </varlistentry>
224
225      <varlistentry id="chpasswd">
226        <term><command>chpasswd</command></term>
227        <listitem>
228          <para>Used to update the passwords of an entire series of user
229          accounts</para>
230          <indexterm zone="ch-system-shadow chpasswd">
231            <primary sortas="b-chpasswd">chpasswd</primary>
232          </indexterm>
233        </listitem>
234      </varlistentry>
235
236      <varlistentry id="chsh">
237        <term><command>chsh</command></term>
238        <listitem>
239          <para>Used to change a user's default login shell</para>
240          <indexterm zone="ch-system-shadow chsh">
241            <primary sortas="b-chsh">chsh</primary>
242          </indexterm>
243        </listitem>
244      </varlistentry>
245
246      <varlistentry id="expiry">
247        <term><command>expiry</command></term>
248        <listitem>
249          <para>Checks and enforces the current password expiration policy</para>
250          <indexterm zone="ch-system-shadow expiry">
251            <primary sortas="b-expiry">expiry</primary>
252          </indexterm>
253        </listitem>
254      </varlistentry>
255
256      <varlistentry id="faillog">
257        <term><command>faillog</command></term>
258        <listitem>
259          <para>Is used to examine the log of login failures, to set a maximum
260          number of failures before an account is blocked, or to reset the
261          failure count</para>
262          <indexterm zone="ch-system-shadow faillog">
263            <primary sortas="b-faillog">faillog</primary>
264          </indexterm>
265        </listitem>
266      </varlistentry>
267
268      <varlistentry id="gpasswd">
269        <term><command>gpasswd</command></term>
270        <listitem>
271          <para>Is used to add and delete members and administrators to
272          groups</para>
273          <indexterm zone="ch-system-shadow gpasswd">
274            <primary sortas="b-gpasswd">gpasswd</primary>
275          </indexterm>
276        </listitem>
277      </varlistentry>
278
279      <varlistentry id="groupadd">
280        <term><command>groupadd</command></term>
281        <listitem>
282          <para>Creates a group with the given name</para>
283          <indexterm zone="ch-system-shadow groupadd">
284            <primary sortas="b-groupadd">groupadd</primary>
285          </indexterm>
286        </listitem>
287      </varlistentry>
288
289      <varlistentry id="groupdel">
290        <term><command>groupdel</command></term>
291        <listitem>
292          <para>Deletes the group with the given name</para>
293          <indexterm zone="ch-system-shadow groupdel">
294            <primary sortas="b-groupdel">groupdel</primary>
295          </indexterm>
296        </listitem>
297      </varlistentry>
298
299      <varlistentry id="groupmod">
300        <term><command>groupmod</command></term>
301        <listitem>
302          <para>Is used to modify the given group's name or GID</para>
303          <indexterm zone="ch-system-shadow groupmod">
304            <primary sortas="b-groupmod">groupmod</primary>
305          </indexterm>
306        </listitem>
307      </varlistentry>
308
309      <varlistentry id="grpck">
310        <term><command>grpck</command></term>
311        <listitem>
312          <para>Verifies the integrity of the group files
313          <filename>/etc/group</filename> and
314          <filename>/etc/gshadow</filename></para>
315          <indexterm zone="ch-system-shadow grpck">
316            <primary sortas="b-grpck">grpck</primary>
317          </indexterm>
318        </listitem>
319      </varlistentry>
320
321      <varlistentry id="grpconv">
322        <term><command>grpconv</command></term>
323        <listitem>
324          <para>Creates or updates the shadow group file from the normal
325          group file</para>
326          <indexterm zone="ch-system-shadow grpconv">
327            <primary sortas="b-grpconv">grpconv</primary>
328          </indexterm>
329        </listitem>
330      </varlistentry>
331
332      <varlistentry id="grpunconv">
333        <term><command>grpunconv</command></term>
334        <listitem>
335          <para>Updates <filename>/etc/group</filename> from
336          <filename>/etc/gshadow</filename> and then deletes the latter</para>
337          <indexterm zone="ch-system-shadow grpunconv">
338            <primary sortas="b-grpunconv">grpunconv</primary>
339          </indexterm>
340        </listitem>
341      </varlistentry>
342
343      <varlistentry id="lastlog">
344        <term><command>lastlog</command></term>
345        <listitem>
346          <para>Reports the most recent login of all users or of a
347          given user</para>
348          <indexterm zone="ch-system-shadow lastlog">
349            <primary sortas="b-lastlog">lastlog</primary>
350          </indexterm>
351        </listitem>
352      </varlistentry>
353
354      <varlistentry id="login">
355        <term><command>login</command></term>
356        <listitem>
357          <para>Is used by the system to let users sign on</para>
358          <indexterm zone="ch-system-shadow login">
359            <primary sortas="b-login">login</primary>
360          </indexterm>
361        </listitem>
362      </varlistentry>
363
364      <varlistentry id="logoutd">
365        <term><command>logoutd</command></term>
366        <listitem>
367          <para>Is a daemon used to enforce restrictions on log-on time
368          and ports</para>
369          <indexterm zone="ch-system-shadow logoutd">
370            <primary sortas="b-logoutd">logoutd</primary>
371          </indexterm>
372        </listitem>
373      </varlistentry>
374
375      <varlistentry id="newgrp">
376        <term><command>newgrp</command></term>
377        <listitem>
378          <para>Is used to change the current GID during a login session</para>
379          <indexterm zone="ch-system-shadow newgrp">
380            <primary sortas="b-newgrp">newgrp</primary>
381          </indexterm>
382        </listitem>
383      </varlistentry>
384
385      <varlistentry id="newusers">
386        <term><command>newusers</command></term>
387        <listitem>
388          <para>Is used to create or update an entire series of user
389          accounts</para>
390          <indexterm zone="ch-system-shadow newusers">
391            <primary sortas="b-newusers">newusers</primary>
392          </indexterm>
393        </listitem>
394      </varlistentry>
395
396      <varlistentry id="nologin">
397        <term><command>nologin</command></term>
398        <listitem>
399          <para>Displays a message that an account is not available. Designed
400          to be used as the default shell for accounts that have been
401          disabled</para>
402          <indexterm zone="ch-system-shadow nologin">
403            <primary sortas="b-nologin">nologin</primary>
404          </indexterm>
405        </listitem>
406      </varlistentry>
407
408      <varlistentry id="passwd">
409        <term><command>passwd</command></term>
410        <listitem>
411          <para>Is used to change the password for a user or group account</para>
412          <indexterm zone="ch-system-shadow passwd">
413            <primary sortas="b-passwd">passwd</primary>
414          </indexterm>
415        </listitem>
416      </varlistentry>
417
418      <varlistentry id="pwck">
419        <term><command>pwck</command></term>
420        <listitem>
421          <para>Verifies the integrity of the password files
422          <filename>/etc/passwd</filename> and
423          <filename>/etc/shadow</filename></para>
424          <indexterm zone="ch-system-shadow pwck">
425            <primary sortas="b-pwck">pwck</primary>
426          </indexterm>
427        </listitem>
428      </varlistentry>
429
430      <varlistentry id="pwconv">
431        <term><command>pwconv</command></term>
432        <listitem>
433          <para>Creates or updates the shadow password file from the normal
434          password file</para>
435          <indexterm zone="ch-system-shadow pwconv">
436            <primary sortas="b-pwconv">pwconv</primary>
437          </indexterm>
438        </listitem>
439      </varlistentry>
440
441      <varlistentry id="pwunconv">
442        <term><command>pwunconv</command></term>
443        <listitem>
444          <para>Updates <filename>/etc/passwd</filename> from
445          <filename>/etc/shadow</filename> and then deletes the latter</para>
446          <indexterm zone="ch-system-shadow pwunconv">
447            <primary sortas="b-pwunconv">pwunconv</primary>
448          </indexterm>
449        </listitem>
450      </varlistentry>
451
452      <varlistentry id="sg">
453        <term><command>sg</command></term>
454        <listitem>
455          <para>Executes a given command while the user's GID
456          is set to that of the given group</para>
457          <indexterm zone="ch-system-shadow sg">
458            <primary sortas="b-sg">sg</primary>
459          </indexterm>
460        </listitem>
461      </varlistentry>
462
463      <varlistentry id="su">
464        <term><command>su</command></term>
465        <listitem>
466          <para>Runs a shell with substitute user and group IDs</para>
467          <indexterm zone="ch-system-shadow su">
468            <primary sortas="b-su">su</primary>
469          </indexterm>
470        </listitem>
471      </varlistentry>
472
473      <varlistentry id="useradd">
474        <term><command>useradd</command></term>
475        <listitem>
476          <para>Creates a new user with the given name, or updates the default
477          new-user information</para>
478          <indexterm zone="ch-system-shadow useradd">
479            <primary sortas="b-useradd">useradd</primary>
480          </indexterm>
481        </listitem>
482      </varlistentry>
483
484      <varlistentry id="userdel">
485        <term><command>userdel</command></term>
486        <listitem>
487          <para>Deletes the given user account</para>
488          <indexterm zone="ch-system-shadow userdel">
489            <primary sortas="b-userdel">userdel</primary>
490          </indexterm>
491        </listitem>
492      </varlistentry>
493
494      <varlistentry id="usermod">
495        <term><command>usermod</command></term>
496        <listitem>
497          <para>Is used to modify the given user's login name, User
498          Identification (UID), shell, initial group, home directory, etc.</para>
499          <indexterm zone="ch-system-shadow usermod">
500            <primary sortas="b-usermod">usermod</primary>
501          </indexterm>
502        </listitem>
503      </varlistentry>
504
505      <varlistentry id="vigr">
506        <term><command>vigr</command></term>
507        <listitem>
508          <para>Edits the <filename>/etc/group</filename> or
509          <filename>/etc/gshadow</filename> files</para>
510          <indexterm zone="ch-system-shadow vigr">
511            <primary sortas="b-vigr">vigr</primary>
512          </indexterm>
513        </listitem>
514      </varlistentry>
515
516      <varlistentry id="vipw">
517        <term><command>vipw</command></term>
518        <listitem>
519          <para>Edits the <filename>/etc/passwd</filename> or
520          <filename>/etc/shadow</filename> files</para>
521          <indexterm zone="ch-system-shadow vipw">
522            <primary sortas="b-vipw">vipw</primary>
523          </indexterm>
524        </listitem>
525      </varlistentry>
526
527      <varlistentry id="libshadow">
528        <term><filename class="libraryfile">libshadow</filename></term>
529        <listitem>
530          <para>Contains functions used by most programs in this package</para>
531          <indexterm zone="ch-system-shadow libshadow">
532            <primary sortas="c-libshadow">libshadow</primary>
533          </indexterm>
534        </listitem>
535      </varlistentry>
536
537    </variablelist>
538
539  </sect2>
540
541</sect1>
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