summaryrefslogtreecommitdiff
path: root/docs/docbook/projdoc/passdb.xml
blob: e17f56ba30db2b8b049deca0a69ebd1cf6ba4de1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
<chapter id="passdb">
<chapterinfo>
	&author.jelmer;
	&author.jerry;
	&author.jeremy;
	&author.jht;
	<author>
		<firstname>Olivier (lem)</firstname><surname>Lemaire</surname>
		<affiliation>
			<orgname>IDEALX</orgname>
			<address><email>olem@IDEALX.org</email></address>
		</affiliation>
	</author>
	
	<pubdate>May 24, 2003</pubdate>
</chapterinfo>
<title>Account Information Databases</title>

<para>
Samba-3 implements a new capability to work concurrently with mulitple account backends.
The possible new combinations of password backends allows Samba-3 a degree of flexibility
and scalability that previously could be achieved only with MS Windows Active Directory.
This chapter describes the new functionality and how to get the most out of it.
</para>

<para>
In the course of development of Samba-3 a number of requests were received to provide the
ability to migrate MS Windows NT4 SAM accounts to Samba-3 without the need to provide
matching Unix/Linux accounts. We called this the <emphasis>Non Unix Accounts (NUA)</emphasis>
capability. The intent was that an administrator could decide to use the <emphasis>tdbsam</emphasis>
backend and by simply specifying <emphasis>"passdb backedn = tdbsam_nua, guest"</emphasis>
this would allow Samba-3 to implement a solution that did not use Unix accounts per se. Late
in the development cycle the team doing this work hit upon some obstacles that prevents this
solution from being used. Given the delays with Samba-3 release a decision was made to NOT
deliver this functionality until a better method of recognising NT Group SIDs from NT User
SIDs could be found. This feature may thus return during the life cycle for the Samba-3 series.
</para>

<note><para>
Samba-3.0.0 does NOT support Non-Unix Account (NUA) operation.
</para></note>

<sect1>
<title>Features and Benefits</title>

<para>
Samba-3 provides for complete backwards compatibility with Samba-2.2.x functionality
as follows:
</para>

<variablelist>
<title>Backwards Compatibility Backends</title>
	<varlistentry><term>Plain Text:</term>
		<listitem>
			<para>
			This option uses nothing but the Unix/Linux <filename>/etc/passwd</filename>
			style back end. On systems that have PAM (Pluggable Authentication Modules)
			support all PAM modules are supported. The behaviour is just as it was with
			Samba-2.2.x, and the protocol limitations imposed by MS Windows clients
			apply likewise.
			</para>
		</listitem>
	</varlistentry>

	<varlistentry><term>smbpasswd:</term>
		<listitem>
			<para>
			This option allows continues use of the <filename>smbpasswd</filename>
			file that maintains a plain ASCII (text) layout that includes the MS Windows
			LanMan and NT encrypted passwords as well as a field that stores some
			account information. This form of password backend does NOT store any of
			the MS Windows NT/200x SAM (Security Account Manager) information needed to
			provide the extended controls that are needed for more comprehensive 
			interoperation with MS Windows NT4 / 200x servers.
			</para>
		</listitem>
	</varlistentry>

	<varlistentry><term>ldapsam_compat (Samba-2.2 LDAP Compatibilty):</term>
		<listitem>
			<para>
			There is a password backend option that allows continued operation with
			a existing OpenLDAP backend that uses the Samba-2.2.x LDAP schema extension.
			This option is provided primarily as a migration tool, although there is
			no reason to force migration at this time.
			</para>
		</listitem>
	</varlistentry>
</variablelist>

<para>
Samba-3 introduces the following new password backend capabilities:
</para>

<variablelist>
<title>New Backends</title>
	<varlistentry><term>tdbsam:</term>
		<listitem>
			<para>
			The <emphasis>tdbsam</emphasis> password backend stores the old <emphasis>
			smbpasswd</emphasis> information PLUS the extended MS Windows NT / 200x
			SAM information into a binary format TDB (trivial database) file.
			The inclusion of the extended information makes it possible for Samba-3
			to implement the same account and system access controls that are possible
			with MS Windows NT4 and MS Windows 200x based systems.
			</para>

			<para>
			The inclusion of the <emphasis>tdbssam</emphasis> capability is a direct
			response to user requests to allow simple site operation without the overhead
			of the complexities of running OpenLDAP. It is recommended to use this only
			for sites that have fewer than 250 users. For larger sites or implementations
			the use of OpenLDAP or of Active Directory integration is strongly recommended.
			</para>
		</listitem>
	</varlistentry>

	<varlistentry><term>ldapsam:</term>
		<listitem>
			<para>
			Samba-3 has a new and extended LDAP implementation that requires configuration
			of OpenLDAP with a new format samba schema. The new format schema file is
			included in the <filename>~samba/examples/LDAP</filename> directory.
			</para>

			<para>
			The new LDAP implmentation significantly expands the control abilities that
			were possible with prior versions of Samba. It is not possible to specify
			"per user" profile settings, home directories, account access controls, and
			much more. Corporate sites will see that the Samba-Team has listened to their
			requests both for capability and to allow greater scalability.
			</para>
		</listitem>
	</varlistentry>

	<varlistentry><term>mysqlsam (MySQL based backend):</term>
		<listitem>
			<para>
			It is expected that the MySQL based SAM will be very popular in some corners.
			This database backend will be on considerable interest to sites that want to
			leverage existing MySQL technology.
			</para>
		</listitem>
	</varlistentry>

	<varlistentry><term>xmlsam (XML based datafile):</term>
		<listitem>
			<para>
			Allows the account and password data to be stored in an XML format
			data file. This backend can not be used for normal operation, it can only 
			be used in conjunction with <command>pdbedit</command>'s pdb2pdb 
			functionality. The DTD that is used might be subject to changes in the future.
			</para>

			<para>
			The xmlsam option can be useful for account migration between database
			backends or backups. Use of this tool will allow the data to be edited before migration
			into another backend format.
			</para>
		</listitem>
	</varlistentry>

	<varlistentry><term>nisplussam:</term>
		<listitem>
			<para>
			The  NIS+ based passdb backend. Takes name NIS domain as an
	                optional argument. Only works with Sun NIS+ servers.
			</para>
		</listitem>
	</varlistentry>

</variablelist>

</sect1>

<sect1>
	<title>Technical Information</title>

	<para>
	Old windows clients send plain text passwords over the wire. Samba can check these
	passwords by crypting them and comparing them to the hash stored in the unix user database.
	</para>
	
	<para>
	Newer windows clients send encrypted passwords (so-called Lanman and NT hashes) over 
	the wire, instead of plain text passwords. The newest clients will send only encrypted
	passwords and refuse to send plain text passwords, unless their registry is tweaked.
	</para>

	<para>
	These passwords can't be converted to unix style encrypted passwords. Because of that
	you can't use the standard unix user database, and you have to store the Lanman and NT
	hashes somewhere else.
	</para>
	
	<para>
	In addition to differently encrypted passwords, windows also stores certain data for each
	user that is not stored in a unix user database. e.g: workstations the user may logon from,
	the location where the users' profile is stored, and so on. Samba retrieves and stores this
	information using a <parameter>passdb backend</parameter>.  Commonly available backends are LDAP, plain text
	file, MySQL and nisplus.  For more information, see the man page for &smb.conf; regarding the 
	<parameter>passdb backend</parameter> parameter.
	</para>

	<sect2>
	<title>Important Notes About Security</title>
		
		<para>
		The unix and SMB password encryption techniques seem similar on the surface. This
		similarity is, however, only skin deep. The unix scheme typically sends clear text
		passwords over the network when logging in. This is bad. The SMB encryption scheme
		never sends the cleartext password over the network but it does store the 16 byte 
		hashed values on disk. This is also bad. Why? Because the 16 byte hashed values
		are a "password equivalent". You cannot derive the user's password from them, but
		they could potentially be used in a modified client to gain access to a server.
		This would require considerable technical knowledge on behalf of the attacker but
		is perfectly possible. You should thus treat the data stored in whatever passdb
		backend you use (smbpasswd file, ldap, mysql) as though it contained the cleartext
		passwords of all your users. Its contents must be kept secret, and the file should
		be protected accordingly.
		</para>
		
		<para>
		Ideally we would like a password scheme that involves neither plain text passwords
		on the net nor on disk. Unfortunately this is not available as Samba is stuck with
		having to be compatible with other SMB systems (WinNT, WfWg, Win95 etc).
		</para>

		<para>
		Windows NT 4.0 Service pack 3 changed the default setting so that plaintext passwords
		are disabled from being sent over the wire. This mandates either the use of encrypted
		password support or edit the Windows NT registry to re-enable plaintext passwords.
		</para>
		
		<para>
		The following versions of MS Windows do not support full domain security protocols,
		although they may log onto a domain environment:
		</para>

		<simplelist>
			<member>MS DOS Network client 3.0 with the basic network redirector installed</member>
			<member>Windows 95 with the network redirector update installed</member>
			<member>Windows 98 [se]</member>
			<member>Windows Me</member>
		</simplelist>

		<note>
		<para>
 		MS Windows XP Home does not have facilities to become a domain member and it can
		not participate in domain logons.
		</para>
		</note>

		<para>
		The following versions of MS Windows fully support domain security protocols.
		</para>

		<simplelist>
			<member>Windows NT 3.5x</member>
			<member>Windows NT 4.0</member>
			<member>Windows 2000 Professional</member>
			<member>Windows 200x Server/Advanced Server</member>
			<member>Windows XP Professional</member>
		</simplelist>
			
		<para>
		All current release of Microsoft SMB/CIFS clients support authentication via the
		SMB Challenge/Response mechanism described here. Enabling clear text authentication
		does not disable the ability of the client to participate in encrypted authentication.
		Instead, it allows the client to negotiate either plain text _or_ encrypted password
		handling.
		</para>

		<para>
		MS Windows clients will cache the encrypted password alone. Where plain text passwords
		are re-enabled, through the appropriate registry change, the plain text password is NEVER
		cached. This means that in the event that a network connections should become disconnected
		(broken) only the cached (encrypted) password will be sent to the resource server to
		affect a auto-reconnect. If the resource server does not support encrypted passwords the
		auto-reconnect will fail. <emphasis>USE OF ENCRYPTED PASSWORDS IS STRONGLY ADVISED.</emphasis>
		</para>

		<sect3>
		<title>Advantages of Encrypted Passwords</title>

			<itemizedlist>
				<listitem><para>Plain text passwords are not passed across 
				the network. Someone using a network sniffer cannot just 
				record passwords going to the SMB server.</para></listitem>

				<listitem><para>Plain text passwords are not stored anywhere in
				memory or on disk.</para></listitem>
			 
				<listitem><para>WinNT doesn't like talking to a server 
				that does not support encrypted passwords. It will refuse 
				to browse the server if the server is also in user level 
				security mode. It will insist on prompting the user for the 
				password on each connection, which is very annoying. The
				only things you can do to stop this is to use SMB encryption.
				</para></listitem>

				<listitem><para>Encrypted password support allows automatic share
				(resource) reconnects.</para></listitem>

				<listitem><para>Encrypted passwords are essential for PDC/BDC
				operation.</para></listitem>
			</itemizedlist>
		</sect3>


		<sect3>
		<title>Advantages of non-encrypted passwords</title>

			<itemizedlist>
				<listitem><para>Plain text passwords are not kept 
				on disk, and are NOT cached in memory. </para></listitem>
				
				<listitem><para>Uses same password file as other unix 
				services such as login and ftp</para></listitem>
				
				<listitem><para>Use of other services (such as telnet and ftp) which
				send plain text passwords over the net, so sending them for SMB
				isn't such a big deal.</para></listitem>
			</itemizedlist>
		</sect3>
	</sect2>

	<sect2>
	<title>Mapping User Identifiers between MS Windows and Unix</title>

	<para>
	Every operation in Unix/Linux requires a user identifier (UID), just as in
	MS Windows NT4 / 200x this requires a Security Identifier (SID). Samba provides
	two means for mapping an MS Windows user to a Unix/Linux UID.
	</para>

	<para>
	Firstly, all Samba SAM (Security Account Management database) accounts require
	a Unix/Linux UID that the account will map to. As users are added to the account
	information database samba-3 will call the <parameter>add user script</parameter>
	interface to add the account to the Samba host OS. In essence all accounts in
	the local SAM require a local user account.
	</para>

	<para>
	The second way to affect Windows SID to Unix UID mapping is via the
	<emphasis>idmap uid, idmap gid</emphasis> parameters in &smb.conf;.
	Please refer to the man page for information about these parameters.
	These parameters are essential when mapping users from a remote SAM server.
	</para>

	</sect2>
</sect1>

<sect1>
<title>Account Management Tools</title>

<para>
Samba-3 provides two (2) tools for management of User and machine accounts. These tools are
called <filename>smbpasswd</filename> and <command>pdbedit</command>. A third tool is under
development but is NOT expected to ship in time for Samba-3.0.0. The new tool will be a TCL/TK
GUI tool that looks much like the MS Windows NT4 Domain User Manager - hopefully this will
be announced in time for samba-3.0.1 release timing.
</para>
	<sect2>
	<title>The <emphasis>smbpasswd</emphasis> Command</title>
	
		<para>
		The smbpasswd utility is a utility similar to the <command>passwd</command>
		or <command>yppasswd</command> programs.  It maintains the two 32 byte password
		fields in the passdb backend.
		</para>

		<para>
		<command>smbpasswd</command> works in a client-server mode where it contacts the
		local smbd to change the user's password on its behalf.This has enormous benefits
		as follows:
		</para>

		<para>
		<command>smbpasswd</command> has the capability to change passwords on Windows NT
		servers (this only works when the request is sent to the NT Primary Domain Controller
		if changing an NT Domain user's password).
		</para>

		<para>
		<command>smbpasswd</command> can be used to:
		</para>
		
		<simplelist>
			<member><emphasis>add</emphasis> user or machine accounts</member>
			<member><emphasis>delete</emphasis> user or machine accounts</member>
			<member><emphasis>enable</emphasis> user or machine accounts</member>
			<member><emphasis>disable</emphasis> user or machine accounts</member>
			<member><emphasis>set to NULL</emphasis> user passwords</member>
			<member><emphasis>manage interdomain trust accounts</emphasis></member>
		</simplelist>
		
		<para>
		To run smbpasswd as a normal user just type:
		</para>
		
		<para>
		<screen>
		<prompt>$ </prompt><userinput>smbpasswd</userinput>
		<prompt>Old SMB password: </prompt><userinput><replaceable>secret</replaceable></userinput>
		</screen>
		For <replaceable>secret</replaceable> type old value here - or hit return if
		there was no old password
		<screen>
		<prompt>New SMB Password: </prompt><userinput><replaceable>new secret</replaceable></userinput>
		<prompt>Repeat New SMB Password: </prompt><userinput><replaceable>new secret</replaceable></userinput>
		</screen>
		</para>
		
		<para>
		If the old value does not match the current value stored for that user, or the two
		new values do not match each other, then the password will not be changed.
		</para>
		
		<para>
		When invoked by an ordinary user it will only allow change of their own
		SMB password.
		</para>
		
		<para>
		When run by root smbpasswd may take an optional argument, specifying
		the user name whose SMB password you wish to change. When run as root, smbpasswd
		does not prompt for or check the old password value, thus allowing root to set passwords 
		for users who have forgotten their passwords.
		</para>
		
		<para>
		<command>smbpasswd</command> is designed to work in the way familiar to UNIX
		users who use the <command>passwd</command> or <command>yppasswd</command> commands.
		While designed for administrative use, this tool provides essential user level
		password change capabilities.
		</para>

		<para>
		For more details on using <command>smbpasswd</command> refer to the man page (the
		definitive reference).
		</para>
	</sect2>

	<sect2>
	<title>The <emphasis>pdbedit</emphasis> Command</title>

		<para>
		<command>pdbedit</command> is a tool that can be used only by root. It is used to
		manage the passdb backend. <command>pdbedit</command> can be used to:
		</para>

		<simplelist>
			<member>add, remove or modify user accounts</member>
			<member>listing user accounts</member>
			<member>migrate user accounts</member>
		</simplelist>

		<para>
		The <command>pdbedit</command> tool is the only one that can manage the account
		security and policy settings. It is capable of all operations that smbpasswd can
		do as well as a super set of them.
		</para>

		<para>
		One particularly important purpose of the <command>pdbedit</command> is to allow
		the migration of account information from one passdb backend to another. See the
		<link linkend="XMLpassdb">XML</link> password backend section of this chapter.
		</para>

		<para>
		The following is an example of the user account information that is stored in
		a tdbsam password backend. This listing was produced by running:
		</para>

		<screen>
		<prompt>$ </prompt><userinput>pdbedit -Lv met</userinput>
		Unix username:        met
		NT username:
		Account Flags:        [UX         ]
		User SID:             S-1-5-21-1449123459-1407424037-3116680435-2004
		Primary Group SID:    S-1-5-21-1449123459-1407424037-3116680435-1201
		Full Name:            Melissa E Terpstra
		Home Directory:       \\frodo\met\Win9Profile
		HomeDir Drive:        H:
		Logon Script:         scripts\logon.bat
		Profile Path:         \\frodo\Profiles\met
		Domain:               MIDEARTH
		Account desc:
		Workstations:         melbelle
		Munged dial:
		Logon time:           0
		Logoff time:          Mon, 18 Jan 2038 20:14:07 GMT
		Kickoff time:         Mon, 18 Jan 2038 20:14:07 GMT
		Password last set:    Sat, 14 Dec 2002 14:37:03 GMT
		Password can change:  Sat, 14 Dec 2002 14:37:03 GMT
		Password must change: Mon, 18 Jan 2038 20:14:07 GMT
		</screen>

		<!-- FIXME: Add note about migrating user accounts -->

	</sect2>
</sect1>

<sect1>
<title>Password Backends</title>

<para>
Samba-3 offers the greatest flexibility in backend account database design of any SMB/CIFS server
technology available today. The flexibility is immediately obvious as one begins to explore this
capability.
</para>

<para>
It is possible to specify not only multiple different password backends, but even multiple
backends of the same type. For example, to use two different tdbsam databases:
</para>

<para>
<programlisting>
[globals]
		passdb backend = tdbsam:/etc/samba/passdb.tdb, \
		tdbsam:/etc/samba/old-passdb.tdb, guest
</programlisting>
</para>


	<sect2>
	<title>Plain Text</title>

		<para>
		Older versions of samba retrieved user information from the unix user database 
		and eventually some other fields from the file <filename>/etc/samba/smbpasswd</filename>
		or <filename>/etc/smbpasswd</filename>. When password encryption is disabled, no 
		SMB specific data is stored at all. Instead all operations are conduected via the way
		that the samba host OS will access it's <filename>/etc/passwd</filename> database.
		eg: On Linux systems that is done via PAM.
		</para>

	</sect2>

	<sect2>
	<title>smbpasswd - Encrypted Password Database</title>

		<para>
		Traditionally, when configuring <ulink url="smb.conf.5.html#ENCRYPTPASSWORDS">"encrypt
		passwords = yes"</ulink> in Samba's <filename>smb.conf</filename> file, user account
		information such as username, LM/NT password hashes, password change times, and account
		flags have been stored in the <filename>smbpasswd(5)</filename> file.  There are several
		disadvantages to this approach for sites with very large numbers of users (counted
		in the thousands).
		</para>

		<itemizedlist>
		<listitem><para>
		The first is that all lookups must be performed sequentially.  Given that
		there are approximately two lookups per domain logon (one for a normal
		session connection such as when mapping a network drive or printer), this
		is a performance bottleneck for large sites.  What is needed is an indexed approach
		such as is used in databases.
		</para></listitem>

		<listitem><para>
		The second problem is that administrators who desire to replicate a smbpasswd file
		to more than one Samba server were left to use external tools such as
		<command>rsync(1)</command> and <command>ssh(1)</command> and wrote custom,
		in-house scripts.
		</para></listitem>

		<listitem><para>
		And finally, the amount of information which is stored in an smbpasswd entry leaves
		no room for additional attributes such as a home directory, password expiration time,
		or even a Relative Identified (RID).
		</para></listitem>
		</itemizedlist>

		<para>
		As a result of these defeciencies, a more robust means of storing user attributes
		used by smbd was developed.  The API which defines access to user accounts
		is commonly referred to as the samdb interface (previously this was called the passdb
		API, and is still so named in the Samba CVS trees). 
		</para>

		<para>
		Samba-3 provides an enhanced set of passdb backends that overcome the deficiencies
		of the smbpasswd plain text database. These are tdbsam, ldapsam, and xmlsam.
		Of these ldapsam will be of most interest to large corporate or enterprise sites.
		</para>

	</sect2>

	<sect2>
	<title>tdbsam</title>

		<para>Samba can store user and machine account data in a "TDB" (Trivial Database).
		Using this backend doesn't require any additional configuration. This backend is
		recommended for new installations that do not require LDAP.
		</para>

		<para>
		As a general guide the Samba-Team do NOT recommend using the tdbsam backend for sites
		that have 250 or more users. Additionally, tdbsam is not capable of scaling for use
		in sites that require PDB/BDC implmentations that requires replication of the account
		database. Clearly, for reason of scalability the use of ldapsam should be encouraged.
		</para>

	</sect2>

	<sect2>
	<title>ldapsam</title>

		<para>
		There are a few points to stress that the ldapsam does not provide. The LDAP
		support referred to in the this documentation does not include:
		</para>

		<itemizedlist>
			<listitem><para>A means of retrieving user account information from
			an Windows 200x Active Directory server.</para></listitem>
			<listitem><para>A means of replacing /etc/passwd.</para></listitem>
		</itemizedlist>

		<para>
		The second item can be accomplished by using LDAP NSS and PAM modules.  LGPL
		versions of these libraries can be obtained from PADL Software
		(<ulink url="http://www.padl.com/">http://www.padl.com/</ulink>). More
		information about the configuration of these packages may be found at "LDAP,
		System Administration; Gerald Carter, O'Reilly; Chapter 6: Replacing NIS".
		Refer to <ulink url="http://safari.oreilly.com/?XmlId=1-56592-491-6">
		http://safari.oreilly.com/?XmlId=1-56592-491-6</ulink> for those who might wish to know
                more about configuration and adminstration of an OpenLDAP server.
		</para>

		<para>
		This document describes how to use an LDAP directory for storing Samba user
		account information traditionally stored in the smbpasswd(5) file.  It is
		assumed that the reader already has a basic understanding of LDAP concepts
		and has a working directory server already installed.  For more information
		on LDAP architectures and Directories, please refer to the following sites.
		</para>

		<itemizedlist>
			<listitem><para>OpenLDAP - <ulink url="http://www.openldap.org/">http://www.openldap.org/</ulink></para></listitem>
			<listitem><para>iPlanet Directory Server -
			 <ulink url="http://iplanet.netscape.com/directory">http://iplanet.netscape.com/directory</ulink></para></listitem>
		</itemizedlist>

		<para>
		Two additional Samba resources which may prove to be helpful are
		</para>

		<itemizedlist>
			<listitem><para>The <ulink url="http://www.unav.es/cti/ldap-smb/ldap-smb-3-howto.html">Samba-PDC-LDAP-HOWTO</ulink>
			maintained by Ignacio Coupeau.</para></listitem>

			<listitem><para>The NT migration scripts from <ulink url="http://samba.idealx.org/">IDEALX</ulink> that are
			geared to manage users and group in such a Samba-LDAP Domain Controller configuration.
			</para></listitem>
		</itemizedlist>

		<sect3>
		<title>Supported LDAP Servers</title>

			<para>
			The LDAP ldapsam code has been developed and tested using the OpenLDAP 2.0 and 2.1 server and
			client libraries.  The same code should work with Netscape's Directory Server and client SDK.
			However, there are bound to be compile errors and bugs. These should not be hard to fix.
			Please submit fixes via <link linkend="bugreport">Bug reporting facility</link>.
			</para>

		</sect3>

		<sect3>
		<title>Schema and Relationship to the RFC 2307 posixAccount</title>


			<para>
			Samba 3.0 includes the necessary schema file for OpenLDAP 2.0 in
			<filename>examples/LDAP/samba.schema</filename>.  The sambaAccount objectclass is given here:
			</para>

<para>
<programlisting>
objectclass ( 1.3.6.1.4.1.7165.2.2.3 NAME 'sambaAccount' SUP top AUXILIARY
    DESC 'Samba Auxilary Account'
    MUST ( uid $ rid )
    MAY  ( cn $ lmPassword $ ntPassword $ pwdLastSet $ logonTime $
           logoffTime $ kickoffTime $ pwdCanChange $ pwdMustChange $ acctFlags $
           displayName $ smbHome $ homeDrive $ scriptPath $ profilePath $
           description $ userWorkstations $ primaryGroupID $ domain ))
</programlisting>
</para>

			<para>
			The <filename>samba.schema</filename> file has been formatted for OpenLDAP 2.0/2.1.
			The OID's are owned by the Samba Team and as such is legal to be openly published.
			If you translate the schema to be used with Netscape DS, please
			submit the modified schema file as a patch to
			<ulink url="mailto:jerry@samba.org">jerry@samba.org</ulink>.
			</para>

			<para>
			Just as the smbpasswd file is meant to store information which supplements a
			user's <filename>/etc/passwd</filename> entry, so is the sambaAccount object
			meant to supplement the UNIX user account information.  A sambaAccount is a
			<constant>STRUCTURAL</constant> objectclass so it can be stored individually
			in the directory.  However, there are several fields (e.g. uid) which overlap
			with the posixAccount objectclass outlined in RFC2307.  This is by design.
			</para>

			<!--olem: we should perhaps have a note about shadowAccounts too as many
			systems use them, isn'it ? -->

			<para>
			In order to store all user account information (UNIX and Samba) in the directory,
			it is necessary to use the sambaAccount and posixAccount objectclasses in
			combination.  However, smbd will still obtain the user's UNIX account
			information via the standard C library calls (e.g. getpwnam(), et. al.).
			This means that the Samba server must also have the LDAP NSS library installed
			and functioning correctly.  This division of information makes it possible to
			store all Samba account information in LDAP, but still maintain UNIX account
			information in NIS while the network is transitioning to a full LDAP infrastructure.
			</para>
		</sect3>

		<sect3>
		<title>OpenLDAP configuration</title>

			<para>
			To include support for the sambaAccount object in an OpenLDAP directory
			server, first copy the samba.schema file to slapd's configuration directory.
			The samba.schema file can be found in the directory <filename>examples/LDAP</filename>
			in the samba source distribution.
			</para>

<para>
<screen>
&rootprompt;<userinput>cp samba.schema /etc/openldap/schema/</userinput>
</screen>
</para>

			<para>
			Next, include the <filename>samba.schema</filename> file in <filename>slapd.conf</filename>.
			The sambaAccount object contains two attributes which depend upon other schema
			files.  The 'uid' attribute is defined in <filename>cosine.schema</filename> and
			the 'displayName' attribute is defined in the <filename>inetorgperson.schema</filename>
			file.  Both of these must be included before the <filename>samba.schema</filename> file.
			</para>

<para>
<programlisting>
## /etc/openldap/slapd.conf

## schema files (core.schema is required by default)
include	           /etc/openldap/schema/core.schema

## needed for sambaAccount
include            /etc/openldap/schema/cosine.schema
include            /etc/openldap/schema/inetorgperson.schema
include            /etc/openldap/schema/samba.schema
include            /etc/openldap/schema/nis.schema
....
</programlisting>
</para>

		<para>
		It is recommended that you maintain some indices on some of the most usefull attributes,
		like in the following example, to speed up searches made on sambaAccount objectclasses
		(and possibly posixAccount and posixGroup as well).
		</para>

<para>
<screen>
# Indices to maintain
## required by OpenLDAP
index objectclass             eq

index cn                      pres,sub,eq
index sn                      pres,sub,eq
## required to support pdb_getsampwnam
index uid                     pres,sub,eq
## required to support pdb_getsambapwrid()
index displayName             pres,sub,eq

## uncomment these if you are storing posixAccount and
## posixGroup entries in the directory as well
##index uidNumber               eq
##index gidNumber               eq
##index memberUid               eq

index   sambaSID              eq
index   sambaPrimaryGroupSID  eq
index   sambaDomainName       eq
index   default               sub
</screen>
</para>

		<para>
		Create the new index by executing:
		</para>

<para>
<screen>
./sbin/slapindex -f slapd.conf
</screen>
</para>

		<para>
		Remember to restart slapd after making these changes:
		</para>

<para>
<screen>
&rootprompt;<userinput>/etc/init.d/slapd restart</userinput>
</screen>
</para>

		</sect3>

		<sect3>
		<title>Initialise the LDAP database</title>

		<para>
		Before you can add accounts to the LDAP database you must create the account containers
		that they will be stored in. The following LDIF file should be modified to match your
		needs (ie: Your DNS entries, etc.).
		</para>
		
<para>
<screen>
# Organization for Samba Base
dn: dc=plainjoe,dc=org
objectclass: dbObject
objectclass: organization
dc: plainjoe
o: Terpstra Org Network
description: The Samba-3 Network LDAP Example

# Organizational Role for Directory Management
db: cn=Manager,dc=plainjoe,dc=org
objectclass: organizationalRole
cn: Manager
description: Directory Manager

# Setting up container for users
dn: ou=People,dc=plainjoe,dc=org
objectclass: top
objectclass: organizationalUnit
ou: People

# Setting up admin handle for People OU
dn: cn=admin,ou=People,dc=plainjoe,dc=org
cn: admin
objectclass: top
objectclass: organizationalRole
objectclass: simpleSecurityObject
userPassword: {SSHA}c3ZM9tBaBo9autm1dL3waDS21+JSfQVz
</screen>
</para>

		<para>
		The userPassword shown above should be generated using <command>slappasswd</command>.
		</para>

		<para>
		The following command will then load the contents of the LDIF file into the LDAP
		database.
		</para>

<para>
<screen>
<prompt>$ </prompt><userinput>slapadd -v -l initldap.dif</userinput>
</screen>
</para>

		<para>
		Do not forget to secure your LDAP server with an adequate access control list,
		as well as an admin password.
		</para>

		<note>
		<para>
		Before Samba can access the LDAP server you need to stoe the LDAP admin password
		into the Samba-3 <filename>secrets.tdb</filename> database by:
		<screen>
&rootprompt; <userinput>smbpasswd -w <replaceable>secret</replaceable></userinput>
		</screen>
		</para>
		</note>

		</sect3>

		<sect3>
		<title>Configuring Samba</title>

			<para>
			The following parameters are available in smb.conf only if your
			version of samba was built with LDAP support. Samba automatically builds with LDAP support if the
			LDAP libraries are found.
			</para>

		<itemizedlist>
			<listitem><para><ulink url="smb.conf.5.html#PASSDBBACKEND">passdb backend = ldapsam:url</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPSSL">ldap ssl</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPADMINDN">ldap admin dn</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPSUFFIX">ldap suffix</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPFILTER">ldap filter</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPMACHINSUFFIX">ldap machine suffix</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPUSERSUFFIX">ldap user suffix</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPDELETEDN">ldap delete dn</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPPASSWDSYNC">ldap passwd sync</ulink></para></listitem>
			<listitem><para><ulink url="smb.conf.5.html#LDAPTRUSTIDS">ldap trust ids</ulink></para></listitem>

		</itemizedlist>

			<para>
			These are described in the &smb.conf; man
			page and so will not be repeated here.  However, a sample smb.conf file for
			use with an LDAP directory could appear as
			</para>

<para>
<programlisting>
## /usr/local/samba/lib/smb.conf
[global]
     security = user
     encrypt passwords = yes

     netbios name = TASHTEGO
     workgroup = NARNIA

     # ldap related parameters

     # define the DN to use when binding to the directory servers
     # The password for this DN is not stored in smb.conf.  Rather it
     # must be set by using 'smbpasswd -w <replaceable>secretpw</replaceable>' to store the
     # passphrase in the secrets.tdb file.  If the "ldap admin dn" values
     # change, this password will need to be reset.
     ldap admin dn = "cn=Samba Manager,ou=people,dc=samba,dc=org"

     # Define the SSL option when connecting to the directory
     # ('off', 'start tls', or 'on' (default))
     ldap ssl = start tls

     # syntax: passdb backend = ldapsam:ldap://server-name[:port]
     passdb backend = ldapsam:ldap://funball.samba.org, guest

     # smbpasswd -x delete the entire dn-entry
     ldap delete dn = no

     # the machine and user suffix added to the base suffix
     # wrote WITHOUT quotes. NULL siffixes by default
     ldap user suffix = ou=People
     ldap machine suffix = ou=Systems

     # Trust unix account information in LDAP
     #  (see the smb.conf manpage for details)
     ldap trust ids = Yes

     # specify the base DN to use when searching the directory
     ldap suffix = "ou=people,dc=samba,dc=org"

     # generally the default ldap search filter is ok
     # ldap filter = "(&amp;(uid=%u)(objectclass=sambaAccount))"
</programlisting>
</para>

		</sect3>

		<sect3>
		<title>Accounts and Groups management</title>

			<para>
			As users accounts are managed thru the sambaAccount objectclass, you should
			modify your existing administration tools to deal with sambaAccount attributes.
			</para>

			<para>
			Machines accounts are managed with the sambaAccount objectclass, just
			like users accounts. However, it's up to you to store thoses accounts
			in a different tree of your LDAP namespace: you should use
			"ou=Groups,dc=plainjoe,dc=org" to store groups and
			"ou=People,dc=plainjoe,dc=org" to store users. Just configure your
			NSS and PAM accordingly (usually, in the /etc/ldap.conf configuration
			file).
			</para>

			<para>
			In Samba release 3.0, the group management system is based on posix
			groups. This means that Samba makes usage of the posixGroup objectclass.
			For now, there is no NT-like group system management (global and local
			groups).
			</para>

		</sect3>

		<sect3>
		<title>Security and sambaAccount</title>


			<para>
			There are two important points to remember when discussing the security
			of sambaAccount entries in the directory.
			</para>

			<itemizedlist>
				<listitem><para><emphasis>Never</emphasis> retrieve the lmPassword or
				ntPassword attribute values over an unencrypted LDAP session.</para></listitem>
				<listitem><para><emphasis>Never</emphasis> allow non-admin users to
				view the lmPassword or ntPassword attribute values.</para></listitem>
			</itemizedlist>

			<para>
			These password hashes are clear text equivalents and can be used to impersonate
			the user without deriving the original clear text strings.  For more information
			on the details of LM/NT password hashes, refer to the
			<link linkend="passdb">Account Information Database</link> section of this chapter.
			</para>

			<para>
			To remedy the first security issue, the "ldap ssl" smb.conf parameter defaults
			to require an encrypted session (<parameter>ldap ssl = on</parameter>) using
			the default port of <constant>636</constant>
			when contacting the directory server.  When using an OpenLDAP server, it
			is possible to use the use the StartTLS LDAP extended  operation in the place of
			LDAPS.  In either case, you are strongly discouraged to disable this security
			(<parameter>ldap ssl = off</parameter>).
			</para>

			<para>
			Note that the LDAPS protocol is deprecated in favor of the LDAPv3 StartTLS
			extended operation.  However, the OpenLDAP library still provides support for
			the older method of securing communication between clients and servers.
			</para>

			<para>
			The second security precaution is to prevent non-administrative users from
			harvesting password hashes from the directory.  This can be done using the
			following ACL in <filename>slapd.conf</filename>:
			</para>

<para>
<programlisting>
## allow the "ldap admin dn" access, but deny everyone else
access to attrs=lmPassword,ntPassword
     by dn="cn=Samba Admin,ou=people,dc=plainjoe,dc=org" write
     by * none
</programlisting>
</para>

		</sect3>

		<sect3>
		<title>LDAP special attributes for sambaAccounts</title>

			<para>
			The sambaAccount objectclass is composed of the following attributes:
			</para>

			<para>
			<table frame="all">
				<title>Attributes in the sambaAccount objectclass (LDAP)</title>
			<tgroup cols="2" align="left">
			<tbody>
				<row><entry><constant>lmPassword</constant></entry><entry>the LANMAN password 16-byte hash stored as a character
						representation of a hexidecimal string.</entry></row>
				<row><entry><constant>ntPassword</constant></entry><entry>the NT password hash 16-byte stored as a character
						representation of a hexidecimal string.</entry></row>
				<row><entry><constant>pwdLastSet</constant></entry><entry>The integer time in seconds since 1970 when the
				<constant>lmPassword</constant> and <constant>ntPassword</constant> attributes were last set.
				</entry></row>

				<row><entry><constant>acctFlags</constant></entry><entry>string of 11 characters surrounded by square brackets []
						representing account flags such as U (user), W(workstation), X(no password expiration),
						I(Domain trust account), H(Home dir required), S(Server trust account),
						and D(disabled).</entry></row>

				<row><entry><constant>logonTime</constant></entry><entry>Integer value currently unused</entry></row>

				<row><entry><constant>logoffTime</constant></entry><entry>Integer value currently unused</entry></row>

				<row><entry><constant>kickoffTime</constant></entry><entry>Integer value currently unused</entry></row>

				<row><entry><constant>pwdCanChange</constant></entry><entry>Integer value currently unused</entry></row>

				<row><entry><constant>pwdMustChange</constant></entry><entry>Integer value currently unused</entry></row>

				<row><entry><constant>homeDrive</constant></entry><entry>specifies the drive letter to which to map the
				UNC path specified by homeDirectory. The drive letter must be specified in the form "X:"
				where X is the letter of the drive to map. Refer to the "logon drive" parameter in the
				smb.conf(5) man page for more information.</entry></row>

				<row><entry><constant>scriptPath</constant></entry><entry>The scriptPath property specifies the path of
				the user's logon script, .CMD, .EXE, or .BAT file. The string can be null. The path
				is relative to the netlogon share.  Refer to the "logon script" parameter in the
				smb.conf(5) man page for more information.</entry></row>

				<row><entry><constant>profilePath</constant></entry><entry>specifies a path to the user's profile.
				This value can be a null string, a local absolute path, or a UNC path.  Refer to the
				"logon path" parameter in the smb.conf(5) man page for more information.</entry></row>

				<row><entry><constant>smbHome</constant></entry><entry>The homeDirectory property specifies the path of
				the home directory for the user. The string can be null. If homeDrive is set and specifies
				a drive letter, homeDirectory should be a UNC path. The path must be a network
				UNC path of the form <filename>\\server\share\directory</filename>. This value can be a null string.
				Refer to the <command>logon home</command> parameter in the &smb.conf; man page for more information.
				</entry></row>

				<row><entry><constant>userWorkstation</constant></entry><entry>character string value currently unused.
				</entry></row>

				<row><entry><constant>rid</constant></entry><entry>the integer representation of the user's relative identifier
				(RID).</entry></row>

				<row><entry><constant>primaryGroupID</constant></entry><entry>the relative identifier (RID) of the primary group
				of the user.</entry></row>

				<row><entry><constant>domain</constant></entry><entry>domain the user is part of.</entry></row>
			</tbody>
			</tgroup></table>
			</para>

			<para>
			The majority of these parameters are only used when Samba is acting as a PDC of
			a domain (refer to the <link linkend="samba-pdc">Samba as a primary domain controller</link> chapter for details on
			how to configure Samba as a Primary Domain Controller). The following four attributes
			are only stored with the sambaAccount entry if the values are non-default values:
			</para>

			<simplelist>
				<member>smbHome</member>
				<member>scriptPath</member>
				<member>logonPath</member>
				<member>homeDrive</member>
			</simplelist>

			<para>
			These attributes are only stored with the sambaAccount entry if
			the values are non-default values.  For example, assume TASHTEGO has now been
			configured as a PDC and that <parameter>logon home = \\%L\%u</parameter> was defined in
			its &smb.conf; file. When a user named "becky" logons to the domain,
			the <parameter>logon home</parameter> string is expanded to \\TASHTEGO\becky.
			If the smbHome attribute exists in the entry "uid=becky,ou=people,dc=samba,dc=org",
			this value is used.  However, if this attribute does not exist, then the value
			of the <parameter>logon home</parameter> parameter is used in its place.  Samba
			will only write the attribute value to the directory entry if the value is
			something other than the default (e.g. <filename>\\MOBY\becky</filename>).
			</para>

		</sect3>

		<sect3>
		<title>Example LDIF Entries for a sambaAccount</title>

			<para>
			The following is a working LDIF with the inclusion of the posixAccount objectclass:
			</para>

	<para>
	<programlisting>
	dn: uid=guest2, ou=people,dc=plainjoe,dc=org
	ntPassword: 878D8014606CDA29677A44EFA1353FC7
	pwdMustChange: 2147483647
	primaryGroupID: 1201
	lmPassword: 552902031BEDE9EFAAD3B435B51404EE
	pwdLastSet: 1010179124
	logonTime: 0
	objectClass: sambaAccount
	uid: guest2
	kickoffTime: 2147483647
	acctFlags: [UX         ]
	logoffTime: 2147483647
	rid: 19006
	pwdCanChange: 0
	</programlisting>
	</para>

			<para>
			The following is an LDIF entry for using both the sambaAccount and
			posixAccount objectclasses:
			</para>

	<para>
	<programlisting>
	dn: uid=gcarter, ou=people,dc=plainjoe,dc=org
	logonTime: 0
	displayName: Gerald Carter
	lmPassword: 552902031BEDE9EFAAD3B435B51404EE
	primaryGroupID: 1201
	objectClass: posixAccount
	objectClass: sambaAccount
	acctFlags: [UX         ]
	userPassword: {crypt}BpM2ej8Rkzogo
	uid: gcarter
	uidNumber: 9000
	cn: Gerald Carter
	loginShell: /bin/bash
	logoffTime: 2147483647
	gidNumber: 100
	kickoffTime: 2147483647
	pwdLastSet: 1010179230
	rid: 19000
	homeDirectory: /home/tashtego/gcarter
	pwdCanChange: 0
	pwdMustChange: 2147483647
	ntPassword: 878D8014606CDA29677A44EFA1353FC7
</programlisting>
	</para>

		</sect3>

		<sect3>
		<title>Password synchronisation</title>

		<para>
		Since version 3.0 samba can update the non-samba (LDAP) password stored with an account. When
		using pam_ldap, this allows changing both unix and windows passwords at once.
		</para>

		<para>The <parameter>ldap passwd sync</parameter> options can have the following values:</para>

		<variablelist>
		       <varlistentry>
			       <term>yes</term>
			       <listitem><para>When the user changes his password, update
					       <constant>ntPassword</constant>, <constant>lmPassword</constant>
					       and the <constant>password</constant> fields.</para></listitem>
		       </varlistentry>

		       <varlistentry>
			       <term>no</term>
			       <listitem><para>Only update <constant>ntPassword</constant> and <constant>lmPassword</constant>.</para></listitem>
		       </varlistentry>

		       <varlistentry>
			       <term>only</term>
			       <listitem><para>Only update the LDAP password and let the LDAP server worry
					       about the other fields. This option is only available when
					       the LDAP library supports LDAP_EXOP_X_MODIFY_PASSWD. </para></listitem>
		       </varlistentry>
		</variablelist>

		<para>More information can be found in the <ulink url="smb.conf.5.html#LDAPPASSWDSYNC">smb.conf</ulink> manpage.
		</para>

		</sect3>

		<sect3>
		<title>ldap trust ids</title>

		<para>
		LDAP Performance can be improved by using the <command>ldap trust ids</command> parameter.
		See the <ulink url="smb.conf.5.html#LDAPTRUSTIDS">smb.conf</ulink> manpage for details.
		</para>

		</sect3>

	</sect2>

	<sect2>
	<title>MySQL</title>

	<para>
	Every so often someone will come along with a great new idea. Storing of user accounts in an
	SQL backend is one of them. Those who want to do this are in the best position to know what the
	specific benefits are to them. This may sound like a cop-out, but in truth we can not attempt
	to document every nitty little detail why certain things of marginal utility to the bulk of
	Samba users might make sense to the rest. In any case, the following instructions should help
	the determined SQL user to implement a working system.
	</para>

		<sect3>
		<title>Creating the database</title>

			<para>
			You either can set up your own table and specify the field names to pdb_mysql (see below
			for the column names) or use the default table. The file <filename>examples/pdb/mysql/mysql.dump</filename> 
			contains the correct queries to create the required tables. Use the command :

			<screen><prompt>$ </prompt><userinput>mysql -u<replaceable>username</replaceable> -h<replaceable>hostname</replaceable> -p<replaceable>password</replaceable> <replaceable>databasename</replaceable> &gt; <filename>/path/to/samba/examples/pdb/mysql/mysql.dump</filename></userinput></screen>
			</para>
		</sect3>

		<sect3>
		<title>Configuring</title>

			<para>This plugin lacks some good documentation, but here is some short info:</para>

			<para>Add a the following to the <parameter>passdb backend</parameter> variable in your &smb.conf;:
			<programlisting>
			passdb backend = [other-plugins] mysql:identifier [other-plugins]
			</programlisting>
			</para>

			<para>The identifier can be any string you like, as long as it doesn't collide with 
			the identifiers of other plugins or other instances of pdb_mysql. If you 
			specify multiple pdb_mysql.so entries in <parameter>passdb backend</parameter>, you also need to 
			use different identifiers!
			</para>

			<para>
				Additional options can be given thru the &smb.conf; file in the <parameter>[global]</parameter> section.
			</para>

		<para>
			<table frame="all">
				<title>Basic smb.conf options for MySQL passdb backend</title>
				<tgroup cols="2" align="left">
				<thead>
					<row><entry>Field</entry><entry>Contents</entry></row>
				</thead>
				<tbody>
					<row><entry>identifier:mysql host</entry><entry>host name, defaults to 'localhost'</entry></row>
					<row><entry>identifier:mysql password</entry><entry></entry></row>
					<row><entry>identifier:mysql user</entry><entry>defaults to 'samba'</entry></row>
					<row><entry>identifier:mysql database</entry><entry>defaults to 'samba'</entry></row>
					<row><entry>identifier:mysql port</entry><entry>defaults to 3306</entry></row>
					<row><entry>identifier:table</entry><entry>Name of the table containing users</entry></row>
				</tbody>
				</tgroup>
			</table>
		</para>

			<warning>
			<para>
			Since the password for the mysql user is stored in the 
			&smb.conf; file, you should make the the &smb.conf; file 
			readable only to the user that runs samba. This is considered a security 
			bug and will be fixed soon.
			</para>
			</warning>

			<para>Names of the columns in this table(I've added column types those columns should have first):</para>

		<para>
			<table frame="all">
				<title>MySQL field names for MySQL passdb backend</title>
				<tgroup cols="3" align="left">
			<thead>		
				<row><entry>Field</entry><entry>Type</entry><entry>Contents</entry></row>
			</thead>
			<tbody>
				<row><entry>identifier:logon time column</entry><entry>int(9)</entry><entry></entry></row>
				<row><entry>identifier:logoff time column</entry><entry>int(9)</entry><entry></entry></row>
				<row><entry>identifier:kickoff time column</entry><entry>int(9)</entry><entry></entry></row>
				<row><entry>identifier:pass last set time column</entry><entry>int(9)</entry><entry></entry></row>
				<row><entry>identifier:pass can change time column</entry><entry>int(9)</entry><entry></entry></row>
				<row><entry>identifier:pass must change time column</entry><entry>int(9)</entry><entry></entry></row>
				<row><entry>identifier:username column</entry><entry>varchar(255)</entry><entry>unix username</entry></row>
				<row><entry>identifier:domain column</entry><entry>varchar(255)</entry><entry>NT domain user is part of</entry></row>
				<row><entry>identifier:nt username column</entry><entry>varchar(255)</entry><entry>NT username</entry></row>
				<row><entry>identifier:fullname column</entry><entry>varchar(255)</entry><entry>Full name of user</entry></row>
				<row><entry>identifier:home dir column</entry><entry>varchar(255)</entry><entry>Unix homedir path</entry></row>
				<row><entry>identifier:dir drive column</entry><entry>varchar(2)</entry><entry>Directory drive path (eg: 'H:')</entry></row>
				<row><entry>identifier:logon script column</entry><entry>varchar(255)</entry><entry>Batch file to run on client side when logging on</entry></row>
				<row><entry>identifier:profile path column</entry><entry>varchar(255)</entry><entry>Path of profile</entry></row>
				<row><entry>identifier:acct desc column</entry><entry>varchar(255)</entry><entry>Some ASCII NT user data</entry></row>
				<row><entry>identifier:workstations column</entry><entry>varchar(255)</entry><entry>Workstations user can logon to (or NULL for all)</entry></row>
				<row><entry>identifier:unknown string column</entry><entry>varchar(255)</entry><entry>unknown string</entry></row>
				<row><entry>identifier:munged dial column</entry><entry>varchar(255)</entry><entry>?</entry></row>
				<row><entry>identifier:user sid column</entry><entry>varchar(255)</entry><entry>NT user SID</entry></row>
				<row><entry>identifier:group sid column</entry><entry>varchar(255)</entry><entry>NT group ID</entry></row>
				<row><entry>identifier:lanman pass column</entry><entry>varchar(255)</entry><entry>encrypted lanman password</entry></row>
				<row><entry>identifier:nt pass column</entry><entry>varchar(255)</entry><entry>encrypted nt passwd</entry></row>
				<row><entry>identifier:plain pass column</entry><entry>varchar(255)</entry><entry>plaintext password</entry></row>
				<row><entry>identifier:acct control column</entry><entry>int(9)</entry><entry>nt user data</entry></row>
				<row><entry>identifier:unknown 3 column</entry><entry>int(9)</entry><entry>unknown</entry></row>
				<row><entry>identifier:logon divs column</entry><entry>int(9)</entry><entry>?</entry></row>
				<row><entry>identifier:hours len column</entry><entry>int(9)</entry><entry>?</entry></row>
				<row><entry>identifier:unknown 5 column</entry><entry>int(9)</entry><entry>unknown</entry></row>
				<row><entry>identifier:unknown 6 column</entry><entry>int(9)</entry><entry>unknown</entry></row>
			</tbody></tgroup>
		</table>
		</para>

			<para>
			Eventually, you can put a colon (:) after the name of each column, which 
			should specify the column to update when updating the table. You can also
			specify nothing behind the colon - then the data from the field will not be 
			updated. 
			</para>

		</sect3>

		<sect3>
		<title>Using plaintext passwords or encrypted password</title>

			<para>
			I strongly discourage the use of plaintext passwords, however, you can use them:
			</para>

			<para>
			If you would like to use plaintext passwords, set
			'identifier:lanman pass column' and 'identifier:nt pass column' to
			'NULL' (without the quotes) and 'identifier:plain pass column' to the
			name of the column containing the plaintext passwords. 
			</para>

			<para>
			If you use encrypted passwords, set the 'identifier:plain pass
			column' to 'NULL' (without the quotes). This is the default.
			</para>

		</sect3>

		<sect3>
		<title>Getting non-column data from the table</title>

			<para>
			It is possible to have not all data in the database and making some 'constant'.
			</para>

			<para>
			For example, you can set 'identifier:fullname column' to : 
			<command>CONCAT(First_name,' ',Sur_name)</command>
			</para>

			<para>
			Or, set 'identifier:workstations column' to :
			<command>NULL</command></para>

			<para>See the MySQL documentation for more language constructs.</para>

		</sect3>
	</sect2>

	<sect2 id="XMLpassdb">
	<title>XML</title>

		<para>This module requires libxml2 to be installed.</para>

		<para>The usage of pdb_xml is pretty straightforward. To export data, use:
		</para>

		<para>
			<prompt>$ </prompt><userinput>pdbedit -e xml:filename</userinput>
		</para>

		<para>
		(where filename is the name of the file to put the data in)
		</para>

		<para>
		To import data, use:
		<prompt>$ </prompt><userinput>pdbedit -i xml:filename</userinput>
		</para>
	</sect2>
</sect1>

<sect1>
<title>Common Errors</title>

	<sect2>
	<title>Users can not logon - Users not in Samba SAM</title>

	<para>
	People forget to put their users in their backend and then complain samba won't authorize them.
	</para>

	</sect2>

	<sect2>
	<title>Users are being added to the wrong backend database</title>

	<para>
	A few complaints have been recieved from users that just moved to samba-3. The following
	&smb.conf; file entries were causing problems, new accounts were being added to the old
	smbpasswd file, not to the tdbsam passdb.tdb file:
	</para>

	<para>
	<programlisting>
	[globals]
		...
		passdb backend = smbpasswd, tdbsam, guest
		...
	</programlisting>
	</para>

	<para>
	Samba will add new accounts to the first entry in the <emphasis>passdb backend</emphasis>
	parameter entry. If you want to update to the tdbsam, then change the entry to:
	</para>

	<para>
	<programlisting>
	[globals]
		...
		passdb backend = tdbsam, smbpasswd, guest
		...
	</programlisting>
	</para>

	</sect2>
</sect1>
</chapter>