summaryrefslogtreecommitdiff
path: root/source3/smbd/process.c
blob: 9d35252e28b58bd564bafa4c4884017ac9d0f72f (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
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
/* 
   Unix SMB/CIFS implementation.
   process incoming packets - main loop
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Volker Lendecke 2005
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"

extern uint16 global_smbpid;
extern int keepalive;
extern struct auth_context *negprot_global_auth_context;
extern int smb_echo_count;

struct timeval smb_last_time;

static char *InBuffer = NULL;
static char *OutBuffer = NULL;
static char *current_inbuf = NULL;

/* 
 * Size of data we can send to client. Set
 *  by the client for all protocols above CORE.
 *  Set by us for CORE protocol.
 */
int max_send = BUFFER_SIZE;
/*
 * Size of the data we can receive. Set by us.
 * Can be modified by the max xmit parameter.
 */
int max_recv = BUFFER_SIZE;

extern int last_message;
extern userdom_struct current_user_info;
extern int smb_read_error;
SIG_ATOMIC_T reload_after_sighup = 0;
SIG_ATOMIC_T got_sig_term = 0;
extern BOOL global_machine_password_needs_changing;
extern int max_send;

/****************************************************************************
 Function to return the current request mid from Inbuffer.
****************************************************************************/

uint16 get_current_mid(void)
{
	return SVAL(InBuffer,smb_mid);
}

/****************************************************************************
 structure to hold a linked list of queued messages.
 for processing.
****************************************************************************/

static struct pending_message_list *deferred_open_queue;

/****************************************************************************
 Function to push a message onto the tail of a linked list of smb messages ready
 for processing.
****************************************************************************/

static BOOL push_queued_message(char *buf, int msg_len,
				struct timeval request_time,
				struct timeval end_time,
				char *private_data, size_t private_len)
{
	struct pending_message_list *tmp_msg;
	struct pending_message_list *msg;

	msg = TALLOC_ZERO_P(NULL, struct pending_message_list);

	if(msg == NULL) {
		DEBUG(0,("push_message: malloc fail (1)\n"));
		return False;
	}

	msg->buf = data_blob_talloc(msg, buf, msg_len);
	if(msg->buf.data == NULL) {
		DEBUG(0,("push_message: malloc fail (2)\n"));
		talloc_free(msg);
		return False;
	}

	msg->request_time = request_time;
	msg->end_time = end_time;

	if (private_data) {
		msg->private_data = data_blob_talloc(msg, private_data,
						     private_len);
		if (msg->private_data.data == NULL) {
			DEBUG(0,("push_message: malloc fail (3)\n"));
			talloc_free(msg);
			return False;
		}
	}

	DLIST_ADD_END(deferred_open_queue, msg, tmp_msg);

	DEBUG(10,("push_message: pushed message length %u on "
		  "deferred_open_queue\n", (unsigned int)msg_len));

	return True;
}

/****************************************************************************
 Function to delete a sharing violation open message by mid.
****************************************************************************/

void remove_deferred_open_smb_message(uint16 mid)
{
	struct pending_message_list *pml;

	for (pml = deferred_open_queue; pml; pml = pml->next) {
		if (mid == SVAL(pml->buf.data,smb_mid)) {
			DEBUG(10,("remove_sharing_violation_open_smb_message: "
				  "deleting mid %u len %u\n",
				  (unsigned int)mid,
				  (unsigned int)pml->buf.length ));
			DLIST_REMOVE(deferred_open_queue, pml);
			talloc_free(pml);
			return;
		}
	}
}

/****************************************************************************
 Move a sharing violation open retry message to the front of the list and
 schedule it for immediate processing.
****************************************************************************/

void schedule_deferred_open_smb_message(uint16 mid)
{
	struct pending_message_list *pml;
	int i = 0;

	for (pml = deferred_open_queue; pml; pml = pml->next) {
		uint16 msg_mid = SVAL(pml->buf.data,smb_mid);
		DEBUG(10,("schedule_deferred_open_smb_message: [%d] msg_mid = %u\n", i++,
			(unsigned int)msg_mid ));
		if (mid == msg_mid) {
			DEBUG(10,("schedule_deferred_open_smb_message: scheduling mid %u\n",
				mid ));
			pml->end_time.tv_sec = 0;
			pml->end_time.tv_usec = 0;
			DLIST_PROMOTE(deferred_open_queue, pml);
			return;
		}
	}

	DEBUG(10,("schedule_deferred_open_smb_message: failed to find message mid %u\n",
		mid ));
}

/****************************************************************************
 Return true if this mid is on the deferred queue.
****************************************************************************/

BOOL open_was_deferred(uint16 mid)
{
	struct pending_message_list *pml;

	for (pml = deferred_open_queue; pml; pml = pml->next) {
		if (SVAL(pml->buf.data,smb_mid) == mid) {
			set_saved_ntstatus(NT_STATUS_OK);
			return True;
		}
	}
	return False;
}

/****************************************************************************
 Return the message queued by this mid.
****************************************************************************/

struct pending_message_list *get_open_deferred_message(uint16 mid)
{
	struct pending_message_list *pml;

	for (pml = deferred_open_queue; pml; pml = pml->next) {
		if (SVAL(pml->buf.data,smb_mid) == mid) {
			return pml;
		}
	}
	return NULL;
}

/****************************************************************************
 Function to push a deferred open smb message onto a linked list of local smb
 messages ready for processing.
****************************************************************************/

BOOL push_deferred_smb_message(uint16 mid,
			       struct timeval request_time,
			       struct timeval timeout,
			       char *private_data, size_t priv_len)
{
	struct timeval end_time;

	end_time = timeval_sum(&request_time, &timeout);

	DEBUG(10,("push_deferred_open_smb_message: pushing message len %u mid %u "
		  "timeout time [%u.%06u]\n",
		  (unsigned int) smb_len(current_inbuf)+4, (unsigned int)mid,
		  (unsigned int)end_time.tv_sec,
		  (unsigned int)end_time.tv_usec));

	return push_queued_message(current_inbuf, smb_len(current_inbuf)+4,
				   request_time, end_time,
				   private_data, priv_len);
}

struct idle_event {
	struct timed_event *te;
	struct timeval interval;
	BOOL (*handler)(const struct timeval *now, void *private_data);
	void *private_data;
};

static void idle_event_handler(struct timed_event *te,
			       const struct timeval *now,
			       void *private_data)
{
	struct idle_event *event =
		talloc_get_type_abort(private_data, struct idle_event);

	talloc_free(event->te);

	if (!event->handler(now, event->private_data)) {
		/* Don't repeat, delete ourselves */
		talloc_free(event);
		return;
	}

	event->te = add_timed_event(event, timeval_sum(now, &event->interval),
				    "idle_event_handler",
				    idle_event_handler, event);

	/* We can't do much but fail here. */
	SMB_ASSERT(event->te != NULL);
}

struct idle_event *add_idle_event(TALLOC_CTX *mem_ctx,
				  struct timeval interval,
				  BOOL (*handler)(const struct timeval *now,
						  void *private_data),
				  void *private_data)
{
	struct idle_event *result;
	struct timeval now = timeval_current();

	result = TALLOC_P(mem_ctx, struct idle_event);
	if (result == NULL) {
		DEBUG(0, ("talloc failed\n"));
		return NULL;
	}

	result->interval = interval;
	result->handler = handler;
	result->private_data = private_data;

	result->te = add_timed_event(result, timeval_sum(&now, &interval),
				     "idle_event_handler",
				     idle_event_handler, result);
	if (result->te == NULL) {
		DEBUG(0, ("add_timed_event failed\n"));
		talloc_free(result);
		return NULL;
	}

	return result;
}

/****************************************************************************
 Do all async processing in here. This includes kernel oplock messages, change
 notify events etc.
****************************************************************************/

static void async_processing(fd_set *pfds)
{
	DEBUG(10,("async_processing: Doing async processing.\n"));

	process_aio_queue();

	process_kernel_oplocks(pfds);

	/* Do the aio check again after receive_local_message as it does a
	   select and may have eaten our signal. */
	/* Is this till true? -- vl */
	process_aio_queue();

	if (got_sig_term) {
		exit_server("Caught TERM signal");
	}

	/* check for async change notify events */
	process_pending_change_notify_queue(0);

	/* check for sighup processing */
	if (reload_after_sighup) {
		change_to_root_user();
		DEBUG(1,("Reloading services after SIGHUP\n"));
		reload_services(False);
		reload_after_sighup = 0;
	}
}

/****************************************************************************
 Add a fd to the set we will be select(2)ing on.
****************************************************************************/

static int select_on_fd(int fd, int maxfd, fd_set *fds)
{
	if (fd != -1) {
		FD_SET(fd, fds);
		maxfd = MAX(maxfd, fd);
	}

	return maxfd;
}

/****************************************************************************
  Do a select on an two fd's - with timeout. 

  If a local udp message has been pushed onto the
  queue (this can only happen during oplock break
  processing) call async_processing()

  If a pending smb message has been pushed onto the
  queue (this can only happen during oplock break
  processing) return this next.

  If the first smbfd is ready then read an smb from it.
  if the second (loopback UDP) fd is ready then read a message
  from it and setup the buffer header to identify the length
  and from address.
  Returns False on timeout or error.
  Else returns True.

The timeout is in milliseconds
****************************************************************************/

static BOOL receive_message_or_smb(char *buffer, int buffer_len, int timeout)
{
	fd_set fds;
	int selrtn;
	struct timeval to = timeval_set(SMBD_SELECT_TIMEOUT, 0);
	int maxfd = 0;

	smb_read_error = 0;

 again:

	if (timeout >= 0) {
		to.tv_sec = timeout / 1000;
		to.tv_usec = (timeout % 1000) * 1000;
	}

	/*
	 * Note that this call must be before processing any SMB
	 * messages as we need to synchronously process any messages
	 * we may have sent to ourselves from the previous SMB.
	 */
	message_dispatch();

	/*
	 * Check to see if we already have a message on the deferred open queue
	 * and it's time to schedule.
	 */
  	if(deferred_open_queue != NULL) {
		BOOL pop_message = False;
		struct pending_message_list *msg = deferred_open_queue;

		if (timeval_is_zero(&msg->end_time)) {
			pop_message = True;
		} else {
			struct timeval tv;
			SMB_BIG_INT tdif;

			GetTimeOfDay(&tv);
			tdif = usec_time_diff(&msg->end_time, &tv);
			if (tdif <= 0) {
				/* Timed out. Schedule...*/
				pop_message = True;
				DEBUG(10,("receive_message_or_smb: queued message timed out.\n"));
			} else {
				/* Make a more accurate select timeout. */
				to.tv_sec = tdif / 1000000;
				to.tv_usec = tdif % 1000000;
				DEBUG(10,("receive_message_or_smb: select with timeout of [%u.%06u]\n",
					(unsigned int)to.tv_sec, (unsigned int)to.tv_usec ));
			}
		}

		if (pop_message) {
			memcpy(buffer, msg->buf.data, MIN(buffer_len, msg->buf.length));
  
			/* We leave this message on the queue so the open code can
			   know this is a retry. */
			DEBUG(5,("receive_message_or_smb: returning deferred open smb message.\n"));
			return True;
		}
	}

	/*
	 * Setup the select read fd set.
	 */

	FD_ZERO(&fds);

	/*
	 * Ensure we process oplock break messages by preference.
	 * We have to do this before the select, after the select
	 * and if the select returns EINTR. This is due to the fact
	 * that the selects called from async_processing can eat an EINTR
	 * caused by a signal (we can't take the break message there).
	 * This is hideously complex - *MUST* be simplified for 3.0 ! JRA.
	 */

	if (oplock_message_waiting(&fds)) {
		DEBUG(10,("receive_message_or_smb: oplock_message is waiting.\n"));
		async_processing(&fds);
		/*
		 * After async processing we must go and do the select again, as
		 * the state of the flag in fds for the server file descriptor is
		 * indeterminate - we may have done I/O on it in the oplock processing. JRA.
		 */
		goto again;
	}

	{
		struct timeval tmp;
		struct timeval *tp = get_timed_events_timeout(&tmp,SMBD_SELECT_TIMEOUT);

		to = timeval_min(&to, tp);
		if (timeval_is_zero(&to)) {
			return True;
		}
	}
	
	maxfd = select_on_fd(smbd_server_fd(), maxfd, &fds);
	maxfd = select_on_fd(change_notify_fd(), maxfd, &fds);
	maxfd = select_on_fd(oplock_notify_fd(), maxfd, &fds);

	selrtn = sys_select(maxfd+1,&fds,NULL,NULL,&to);

	/* if we get EINTR then maybe we have received an oplock
	   signal - treat this as select returning 1. This is ugly, but
	   is the best we can do until the oplock code knows more about
	   signals */
	if (selrtn == -1 && errno == EINTR) {
		async_processing(&fds);
		/*
		 * After async processing we must go and do the select again, as
		 * the state of the flag in fds for the server file descriptor is
		 * indeterminate - we may have done I/O on it in the oplock processing. JRA.
		 */
		goto again;
	}

	/* Check if error */
	if (selrtn == -1) {
		/* something is wrong. Maybe the socket is dead? */
		smb_read_error = READ_ERROR;
		return False;
	} 
    
	/* Did we timeout ? */
	if (selrtn == 0) {
		smb_read_error = READ_TIMEOUT;
		return False;
	}

	/*
	 * Ensure we process oplock break messages by preference.
	 * This is IMPORTANT ! Otherwise we can starve other processes
	 * sending us an oplock break message. JRA.
	 */

	if (oplock_message_waiting(&fds)) {
		async_processing(&fds);
		/*
		 * After async processing we must go and do the select again, as
		 * the state of the flag in fds for the server file descriptor is
		 * indeterminate - we may have done I/O on it in the oplock processing. JRA.
		 */
		goto again;
	}
	
	return receive_smb(smbd_server_fd(), buffer, 0);
}

/****************************************************************************
Get the next SMB packet, doing the local message processing automatically.
****************************************************************************/

BOOL receive_next_smb(char *inbuf, int bufsize, int timeout)
{
	BOOL got_keepalive;
	BOOL ret;

	do {
		ret = receive_message_or_smb(inbuf,bufsize,timeout);
		
		got_keepalive = (ret && (CVAL(inbuf,0) == SMBkeepalive));
	} while (ret && got_keepalive);

	return ret;
}

/****************************************************************************
 We're terminating and have closed all our files/connections etc.
 If there are any pending local messages we need to respond to them
 before termination so that other smbds don't think we just died whilst
 holding oplocks.
****************************************************************************/

void respond_to_all_remaining_local_messages(void)
{
	/*
	 * Assert we have no exclusive open oplocks.
	 */

	if(get_number_of_exclusive_open_oplocks()) {
		DEBUG(0,("respond_to_all_remaining_local_messages: PANIC : we have %d exclusive oplocks.\n",
			get_number_of_exclusive_open_oplocks() ));
		return;
	}

	process_kernel_oplocks(NULL);

	return;
}


/*
These flags determine some of the permissions required to do an operation 

Note that I don't set NEED_WRITE on some write operations because they
are used by some brain-dead clients when printing, and I don't want to
force write permissions on print services.
*/
#define AS_USER (1<<0)
#define NEED_WRITE (1<<1)
#define TIME_INIT (1<<2)
#define CAN_IPC (1<<3)
#define AS_GUEST (1<<5)
#define DO_CHDIR (1<<6)

/* 
   define a list of possible SMB messages and their corresponding
   functions. Any message that has a NULL function is unimplemented -
   please feel free to contribute implementations!
*/
static const struct smb_message_struct {
	const char *name;
	int (*fn)(connection_struct *conn, char *, char *, int, int);
	int flags;
} smb_messages[256] = {

/* 0x00 */ { "SMBmkdir",reply_mkdir,AS_USER | NEED_WRITE},
/* 0x01 */ { "SMBrmdir",reply_rmdir,AS_USER | NEED_WRITE},
/* 0x02 */ { "SMBopen",reply_open,AS_USER },
/* 0x03 */ { "SMBcreate",reply_mknew,AS_USER},
/* 0x04 */ { "SMBclose",reply_close,AS_USER | CAN_IPC },
/* 0x05 */ { "SMBflush",reply_flush,AS_USER},
/* 0x06 */ { "SMBunlink",reply_unlink,AS_USER | NEED_WRITE }, 
/* 0x07 */ { "SMBmv",reply_mv,AS_USER | NEED_WRITE },
/* 0x08 */ { "SMBgetatr",reply_getatr,AS_USER},
/* 0x09 */ { "SMBsetatr",reply_setatr,AS_USER | NEED_WRITE},
/* 0x0a */ { "SMBread",reply_read,AS_USER},
/* 0x0b */ { "SMBwrite",reply_write,AS_USER | CAN_IPC },
/* 0x0c */ { "SMBlock",reply_lock,AS_USER},
/* 0x0d */ { "SMBunlock",reply_unlock,AS_USER},
/* 0x0e */ { "SMBctemp",reply_ctemp,AS_USER },
/* 0x0f */ { "SMBmknew",reply_mknew,AS_USER}, 
/* 0x10 */ { "SMBchkpth",reply_chkpth,AS_USER},
/* 0x11 */ { "SMBexit",reply_exit,DO_CHDIR},
/* 0x12 */ { "SMBlseek",reply_lseek,AS_USER},
/* 0x13 */ { "SMBlockread",reply_lockread,AS_USER},
/* 0x14 */ { "SMBwriteunlock",reply_writeunlock,AS_USER},
/* 0x15 */ { NULL, NULL, 0 },
/* 0x16 */ { NULL, NULL, 0 },
/* 0x17 */ { NULL, NULL, 0 },
/* 0x18 */ { NULL, NULL, 0 },
/* 0x19 */ { NULL, NULL, 0 },
/* 0x1a */ { "SMBreadbraw",reply_readbraw,AS_USER},
/* 0x1b */ { "SMBreadBmpx",reply_readbmpx,AS_USER},
/* 0x1c */ { "SMBreadBs",NULL,0 },
/* 0x1d */ { "SMBwritebraw",reply_writebraw,AS_USER},
/* 0x1e */ { "SMBwriteBmpx",reply_writebmpx,AS_USER},
/* 0x1f */ { "SMBwriteBs",reply_writebs,AS_USER},
/* 0x20 */ { "SMBwritec",NULL,0},
/* 0x21 */ { NULL, NULL, 0 },
/* 0x22 */ { "SMBsetattrE",reply_setattrE,AS_USER | NEED_WRITE },
/* 0x23 */ { "SMBgetattrE",reply_getattrE,AS_USER },
/* 0x24 */ { "SMBlockingX",reply_lockingX,AS_USER },
/* 0x25 */ { "SMBtrans",reply_trans,AS_USER | CAN_IPC },
/* 0x26 */ { "SMBtranss",NULL,AS_USER | CAN_IPC},
/* 0x27 */ { "SMBioctl",reply_ioctl,0},
/* 0x28 */ { "SMBioctls",NULL,AS_USER},
/* 0x29 */ { "SMBcopy",reply_copy,AS_USER | NEED_WRITE },
/* 0x2a */ { "SMBmove",NULL,AS_USER | NEED_WRITE },
/* 0x2b */ { "SMBecho",reply_echo,0},
/* 0x2c */ { "SMBwriteclose",reply_writeclose,AS_USER},
/* 0x2d */ { "SMBopenX",reply_open_and_X,AS_USER | CAN_IPC },
/* 0x2e */ { "SMBreadX",reply_read_and_X,AS_USER | CAN_IPC },
/* 0x2f */ { "SMBwriteX",reply_write_and_X,AS_USER | CAN_IPC },
/* 0x30 */ { NULL, NULL, 0 },
/* 0x31 */ { NULL, NULL, 0 },
/* 0x32 */ { "SMBtrans2", reply_trans2, AS_USER | CAN_IPC },
/* 0x33 */ { "SMBtranss2", reply_transs2, AS_USER},
/* 0x34 */ { "SMBfindclose", reply_findclose,AS_USER},
/* 0x35 */ { "SMBfindnclose", reply_findnclose, AS_USER},
/* 0x36 */ { NULL, NULL, 0 },
/* 0x37 */ { NULL, NULL, 0 },
/* 0x38 */ { NULL, NULL, 0 },
/* 0x39 */ { NULL, NULL, 0 },
/* 0x3a */ { NULL, NULL, 0 },
/* 0x3b */ { NULL, NULL, 0 },
/* 0x3c */ { NULL, NULL, 0 },
/* 0x3d */ { NULL, NULL, 0 },
/* 0x3e */ { NULL, NULL, 0 },
/* 0x3f */ { NULL, NULL, 0 },
/* 0x40 */ { NULL, NULL, 0 },
/* 0x41 */ { NULL, NULL, 0 },
/* 0x42 */ { NULL, NULL, 0 },
/* 0x43 */ { NULL, NULL, 0 },
/* 0x44 */ { NULL, NULL, 0 },
/* 0x45 */ { NULL, NULL, 0 },
/* 0x46 */ { NULL, NULL, 0 },
/* 0x47 */ { NULL, NULL, 0 },
/* 0x48 */ { NULL, NULL, 0 },
/* 0x49 */ { NULL, NULL, 0 },
/* 0x4a */ { NULL, NULL, 0 },
/* 0x4b */ { NULL, NULL, 0 },
/* 0x4c */ { NULL, NULL, 0 },
/* 0x4d */ { NULL, NULL, 0 },
/* 0x4e */ { NULL, NULL, 0 },
/* 0x4f */ { NULL, NULL, 0 },
/* 0x50 */ { NULL, NULL, 0 },
/* 0x51 */ { NULL, NULL, 0 },
/* 0x52 */ { NULL, NULL, 0 },
/* 0x53 */ { NULL, NULL, 0 },
/* 0x54 */ { NULL, NULL, 0 },
/* 0x55 */ { NULL, NULL, 0 },
/* 0x56 */ { NULL, NULL, 0 },
/* 0x57 */ { NULL, NULL, 0 },
/* 0x58 */ { NULL, NULL, 0 },
/* 0x59 */ { NULL, NULL, 0 },
/* 0x5a */ { NULL, NULL, 0 },
/* 0x5b */ { NULL, NULL, 0 },
/* 0x5c */ { NULL, NULL, 0 },
/* 0x5d */ { NULL, NULL, 0 },
/* 0x5e */ { NULL, NULL, 0 },
/* 0x5f */ { NULL, NULL, 0 },
/* 0x60 */ { NULL, NULL, 0 },
/* 0x61 */ { NULL, NULL, 0 },
/* 0x62 */ { NULL, NULL, 0 },
/* 0x63 */ { NULL, NULL, 0 },
/* 0x64 */ { NULL, NULL, 0 },
/* 0x65 */ { NULL, NULL, 0 },
/* 0x66 */ { NULL, NULL, 0 },
/* 0x67 */ { NULL, NULL, 0 },
/* 0x68 */ { NULL, NULL, 0 },
/* 0x69 */ { NULL, NULL, 0 },
/* 0x6a */ { NULL, NULL, 0 },
/* 0x6b */ { NULL, NULL, 0 },
/* 0x6c */ { NULL, NULL, 0 },
/* 0x6d */ { NULL, NULL, 0 },
/* 0x6e */ { NULL, NULL, 0 },
/* 0x6f */ { NULL, NULL, 0 },
/* 0x70 */ { "SMBtcon",reply_tcon,0},
/* 0x71 */ { "SMBtdis",reply_tdis,DO_CHDIR},
/* 0x72 */ { "SMBnegprot",reply_negprot,0},
/* 0x73 */ { "SMBsesssetupX",reply_sesssetup_and_X,0},
/* 0x74 */ { "SMBulogoffX", reply_ulogoffX, 0}, /* ulogoff doesn't give a valid TID */
/* 0x75 */ { "SMBtconX",reply_tcon_and_X,0},
/* 0x76 */ { NULL, NULL, 0 },
/* 0x77 */ { NULL, NULL, 0 },
/* 0x78 */ { NULL, NULL, 0 },
/* 0x79 */ { NULL, NULL, 0 },
/* 0x7a */ { NULL, NULL, 0 },
/* 0x7b */ { NULL, NULL, 0 },
/* 0x7c */ { NULL, NULL, 0 },
/* 0x7d */ { NULL, NULL, 0 },
/* 0x7e */ { NULL, NULL, 0 },
/* 0x7f */ { NULL, NULL, 0 },
/* 0x80 */ { "SMBdskattr",reply_dskattr,AS_USER},
/* 0x81 */ { "SMBsearch",reply_search,AS_USER},
/* 0x82 */ { "SMBffirst",reply_search,AS_USER},
/* 0x83 */ { "SMBfunique",reply_search,AS_USER},
/* 0x84 */ { "SMBfclose",reply_fclose,AS_USER},
/* 0x85 */ { NULL, NULL, 0 },
/* 0x86 */ { NULL, NULL, 0 },
/* 0x87 */ { NULL, NULL, 0 },
/* 0x88 */ { NULL, NULL, 0 },
/* 0x89 */ { NULL, NULL, 0 },
/* 0x8a */ { NULL, NULL, 0 },
/* 0x8b */ { NULL, NULL, 0 },
/* 0x8c */ { NULL, NULL, 0 },
/* 0x8d */ { NULL, NULL, 0 },
/* 0x8e */ { NULL, NULL, 0 },
/* 0x8f */ { NULL, NULL, 0 },
/* 0x90 */ { NULL, NULL, 0 },
/* 0x91 */ { NULL, NULL, 0 },
/* 0x92 */ { NULL, NULL, 0 },
/* 0x93 */ { NULL, NULL, 0 },
/* 0x94 */ { NULL, NULL, 0 },
/* 0x95 */ { NULL, NULL, 0 },
/* 0x96 */ { NULL, NULL, 0 },
/* 0x97 */ { NULL, NULL, 0 },
/* 0x98 */ { NULL, NULL, 0 },
/* 0x99 */ { NULL, NULL, 0 },
/* 0x9a */ { NULL, NULL, 0 },
/* 0x9b */ { NULL, NULL, 0 },
/* 0x9c */ { NULL, NULL, 0 },
/* 0x9d */ { NULL, NULL, 0 },
/* 0x9e */ { NULL, NULL, 0 },
/* 0x9f */ { NULL, NULL, 0 },
/* 0xa0 */ { "SMBnttrans", reply_nttrans, AS_USER | CAN_IPC },
/* 0xa1 */ { "SMBnttranss", reply_nttranss, AS_USER | CAN_IPC },
/* 0xa2 */ { "SMBntcreateX", reply_ntcreate_and_X, AS_USER | CAN_IPC },
/* 0xa3 */ { NULL, NULL, 0 },
/* 0xa4 */ { "SMBntcancel", reply_ntcancel, 0 },
/* 0xa5 */ { "SMBntrename", reply_ntrename, AS_USER | NEED_WRITE },
/* 0xa6 */ { NULL, NULL, 0 },
/* 0xa7 */ { NULL, NULL, 0 },
/* 0xa8 */ { NULL, NULL, 0 },
/* 0xa9 */ { NULL, NULL, 0 },
/* 0xaa */ { NULL, NULL, 0 },
/* 0xab */ { NULL, NULL, 0 },
/* 0xac */ { NULL, NULL, 0 },
/* 0xad */ { NULL, NULL, 0 },
/* 0xae */ { NULL, NULL, 0 },
/* 0xaf */ { NULL, NULL, 0 },
/* 0xb0 */ { NULL, NULL, 0 },
/* 0xb1 */ { NULL, NULL, 0 },
/* 0xb2 */ { NULL, NULL, 0 },
/* 0xb3 */ { NULL, NULL, 0 },
/* 0xb4 */ { NULL, NULL, 0 },
/* 0xb5 */ { NULL, NULL, 0 },
/* 0xb6 */ { NULL, NULL, 0 },
/* 0xb7 */ { NULL, NULL, 0 },
/* 0xb8 */ { NULL, NULL, 0 },
/* 0xb9 */ { NULL, NULL, 0 },
/* 0xba */ { NULL, NULL, 0 },
/* 0xbb */ { NULL, NULL, 0 },
/* 0xbc */ { NULL, NULL, 0 },
/* 0xbd */ { NULL, NULL, 0 },
/* 0xbe */ { NULL, NULL, 0 },
/* 0xbf */ { NULL, NULL, 0 },
/* 0xc0 */ { "SMBsplopen",reply_printopen,AS_USER},
/* 0xc1 */ { "SMBsplwr",reply_printwrite,AS_USER},
/* 0xc2 */ { "SMBsplclose",reply_printclose,AS_USER},
/* 0xc3 */ { "SMBsplretq",reply_printqueue,AS_USER},
/* 0xc4 */ { NULL, NULL, 0 },
/* 0xc5 */ { NULL, NULL, 0 },
/* 0xc6 */ { NULL, NULL, 0 },
/* 0xc7 */ { NULL, NULL, 0 },
/* 0xc8 */ { NULL, NULL, 0 },
/* 0xc9 */ { NULL, NULL, 0 },
/* 0xca */ { NULL, NULL, 0 },
/* 0xcb */ { NULL, NULL, 0 },
/* 0xcc */ { NULL, NULL, 0 },
/* 0xcd */ { NULL, NULL, 0 },
/* 0xce */ { NULL, NULL, 0 },
/* 0xcf */ { NULL, NULL, 0 },
/* 0xd0 */ { "SMBsends",reply_sends,AS_GUEST},
/* 0xd1 */ { "SMBsendb",NULL,AS_GUEST},
/* 0xd2 */ { "SMBfwdname",NULL,AS_GUEST},
/* 0xd3 */ { "SMBcancelf",NULL,AS_GUEST},
/* 0xd4 */ { "SMBgetmac",NULL,AS_GUEST},
/* 0xd5 */ { "SMBsendstrt",reply_sendstrt,AS_GUEST},
/* 0xd6 */ { "SMBsendend",reply_sendend,AS_GUEST},
/* 0xd7 */ { "SMBsendtxt",reply_sendtxt,AS_GUEST},
/* 0xd8 */ { NULL, NULL, 0 },
/* 0xd9 */ { NULL, NULL, 0 },
/* 0xda */ { NULL, NULL, 0 },
/* 0xdb */ { NULL, NULL, 0 },
/* 0xdc */ { NULL, NULL, 0 },
/* 0xdd */ { NULL, NULL, 0 },
/* 0xde */ { NULL, NULL, 0 },
/* 0xdf */ { NULL, NULL, 0 },
/* 0xe0 */ { NULL, NULL, 0 },
/* 0xe1 */ { NULL, NULL, 0 },
/* 0xe2 */ { NULL, NULL, 0 },
/* 0xe3 */ { NULL, NULL, 0 },
/* 0xe4 */ { NULL, NULL, 0 },
/* 0xe5 */ { NULL, NULL, 0 },
/* 0xe6 */ { NULL, NULL, 0 },
/* 0xe7 */ { NULL, NULL, 0 },
/* 0xe8 */ { NULL, NULL, 0 },
/* 0xe9 */ { NULL, NULL, 0 },
/* 0xea */ { NULL, NULL, 0 },
/* 0xeb */ { NULL, NULL, 0 },
/* 0xec */ { NULL, NULL, 0 },
/* 0xed */ { NULL, NULL, 0 },
/* 0xee */ { NULL, NULL, 0 },
/* 0xef */ { NULL, NULL, 0 },
/* 0xf0 */ { NULL, NULL, 0 },
/* 0xf1 */ { NULL, NULL, 0 },
/* 0xf2 */ { NULL, NULL, 0 },
/* 0xf3 */ { NULL, NULL, 0 },
/* 0xf4 */ { NULL, NULL, 0 },
/* 0xf5 */ { NULL, NULL, 0 },
/* 0xf6 */ { NULL, NULL, 0 },
/* 0xf7 */ { NULL, NULL, 0 },
/* 0xf8 */ { NULL, NULL, 0 },
/* 0xf9 */ { NULL, NULL, 0 },
/* 0xfa */ { NULL, NULL, 0 },
/* 0xfb */ { NULL, NULL, 0 },
/* 0xfc */ { NULL, NULL, 0 },
/* 0xfd */ { NULL, NULL, 0 },
/* 0xfe */ { NULL, NULL, 0 },
/* 0xff */ { NULL, NULL, 0 }

};

/*******************************************************************
 Dump a packet to a file.
********************************************************************/

static void smb_dump(const char *name, int type, char *data, ssize_t len)
{
	int fd, i;
	pstring fname;
	if (DEBUGLEVEL < 50) return;

	if (len < 4) len = smb_len(data)+4;
	for (i=1;i<100;i++) {
		slprintf(fname,sizeof(fname)-1, "/tmp/%s.%d.%s", name, i,
				type ? "req" : "resp");
		fd = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0644);
		if (fd != -1 || errno != EEXIST) break;
	}
	if (fd != -1) {
		ssize_t ret = write(fd, data, len);
		if (ret != len)
			DEBUG(0,("smb_dump: problem: write returned %d\n", (int)ret ));
		close(fd);
		DEBUG(0,("created %s len %lu\n", fname, (unsigned long)len));
	}
}


/****************************************************************************
 Do a switch on the message type, and return the response size
****************************************************************************/

static int switch_message(int type,char *inbuf,char *outbuf,int size,int bufsize)
{
	static pid_t pid= (pid_t)-1;
	int outsize = 0;

	type &= 0xff;

	if (pid == (pid_t)-1)
		pid = sys_getpid();

	errno = 0;
	set_saved_ntstatus(NT_STATUS_OK);

	last_message = type;

	/* Make sure this is an SMB packet. smb_size contains NetBIOS header so subtract 4 from it. */
	if ((strncmp(smb_base(inbuf),"\377SMB",4) != 0) || (size < (smb_size - 4))) {
		DEBUG(2,("Non-SMB packet of length %d. Terminating server\n",smb_len(inbuf)));
		exit_server("Non-SMB packet");
		return(-1);
	}

	/* yuck! this is an interim measure before we get rid of our
		current inbuf/outbuf system */
	global_smbpid = SVAL(inbuf,smb_pid);

	if (smb_messages[type].fn == NULL) {
		DEBUG(0,("Unknown message type %d!\n",type));
		smb_dump("Unknown", 1, inbuf, size);
		outsize = reply_unknown(inbuf,outbuf);
	} else {
		int flags = smb_messages[type].flags;
		static uint16 last_session_tag = UID_FIELD_INVALID;
		/* In share mode security we must ignore the vuid. */
		uint16 session_tag = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID : SVAL(inbuf,smb_uid);
		connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));

		DEBUG(3,("switch message %s (pid %d) conn 0x%lx\n",smb_fn_name(type),(int)pid,(unsigned long)conn));

		smb_dump(smb_fn_name(type), 1, inbuf, size);

		/* Ensure this value is replaced in the incoming packet. */
		SSVAL(inbuf,smb_uid,session_tag);

		/*
		 * Ensure the correct username is in current_user_info.
		 * This is a really ugly bugfix for problems with
		 * multiple session_setup_and_X's being done and
		 * allowing %U and %G substitutions to work correctly.
		 * There is a reason this code is done here, don't
		 * move it unless you know what you're doing... :-).
		 * JRA.
		 */

		if (session_tag != last_session_tag) {
			user_struct *vuser = NULL;

			last_session_tag = session_tag;
			if(session_tag != UID_FIELD_INVALID)
				vuser = get_valid_user_struct(session_tag);           
			if(vuser != NULL)
				set_current_user_info(&vuser->user);
		}

		/* does this protocol need to be run as root? */
		if (!(flags & AS_USER))
			change_to_root_user();

		/* does this protocol need a valid tree connection? */
		if ((flags & AS_USER) && !conn) {
			/* Amazingly, the error code depends on the command (from Samba4). */
			if (type == SMBntcreateX) {
				return ERROR_NT(NT_STATUS_INVALID_HANDLE);
			} else {
				return ERROR_DOS(ERRSRV, ERRinvnid);
			}
		}


		/* does this protocol need to be run as the connected user? */
		if ((flags & AS_USER) && !change_to_user(conn,session_tag)) {
			if (flags & AS_GUEST) 
				flags &= ~AS_USER;
			else
				return(ERROR_FORCE_DOS(ERRSRV,ERRbaduid));
		}

		/* this code is to work around a bug is MS client 3 without
			introducing a security hole - it needs to be able to do
			print queue checks as guest if it isn't logged in properly */
		if (flags & AS_USER)
			flags &= ~AS_GUEST;

		/* does it need write permission? */
		if ((flags & NEED_WRITE) && !CAN_WRITE(conn))
			return(ERROR_DOS(ERRSRV,ERRaccess));

		/* ipc services are limited */
		if (IS_IPC(conn) && (flags & AS_USER) && !(flags & CAN_IPC))
			return(ERROR_DOS(ERRSRV,ERRaccess));	    

		/* load service specific parameters */
		if (conn) {
			if (!set_current_service(conn,SVAL(inbuf,smb_flg),(flags & (AS_USER|DO_CHDIR)?True:False))) {
				return(ERROR_DOS(ERRSRV,ERRaccess));
			}
			conn->num_smb_operations++;
		}

		/* does this protocol need to be run as guest? */
		if ((flags & AS_GUEST) && (!change_to_guest() || 
				!check_access(smbd_server_fd(), lp_hostsallow(-1), lp_hostsdeny(-1))))
			return(ERROR_DOS(ERRSRV,ERRaccess));

		current_inbuf = inbuf; /* In case we need to defer this message in open... */
		outsize = smb_messages[type].fn(conn, inbuf,outbuf,size,bufsize);
	}

	smb_dump(smb_fn_name(type), 0, outbuf, outsize);

	return(outsize);
}


/****************************************************************************
 Construct a reply to the incoming packet.
****************************************************************************/

static int construct_reply(char *inbuf,char *outbuf,int size,int bufsize)
{
	int type = CVAL(inbuf,smb_com);
	int outsize = 0;
	int msg_type = CVAL(inbuf,0);

	GetTimeOfDay(&smb_last_time);

	chain_size = 0;
	file_chain_reset();
	reset_chain_p();

	if (msg_type != 0)
		return(reply_special(inbuf,outbuf));  

	construct_reply_common(inbuf, outbuf);

	outsize = switch_message(type,inbuf,outbuf,size,bufsize);

	outsize += chain_size;

	if(outsize > 4)
		smb_setlen(outbuf,outsize - 4);
	return(outsize);
}

/****************************************************************************
 Keep track of the number of running smbd's. This functionality is used to
 'hard' limit Samba overhead on resource constrained systems. 
****************************************************************************/

static BOOL process_count_update_successful = False;

static int32 increment_smbd_process_count(void)
{
	int32 total_smbds;

	if (lp_max_smbd_processes()) {
		total_smbds = 0;
		if (tdb_change_int32_atomic(conn_tdb_ctx(), "INFO/total_smbds", &total_smbds, 1) == -1)
			return 1;
		process_count_update_successful = True;
		return total_smbds + 1;
	}
	return 1;
}

void decrement_smbd_process_count(void)
{
	int32 total_smbds;

	if (lp_max_smbd_processes() && process_count_update_successful) {
		total_smbds = 1;
		tdb_change_int32_atomic(conn_tdb_ctx(), "INFO/total_smbds", &total_smbds, -1);
	}
}

static BOOL smbd_process_limit(void)
{
	int32  total_smbds;
	
	if (lp_max_smbd_processes()) {

		/* Always add one to the smbd process count, as exit_server() always
		 * subtracts one.
		 */

		if (!conn_tdb_ctx()) {
			DEBUG(0,("smbd_process_limit: max smbd processes parameter set with status parameter not \
set. Ignoring max smbd restriction.\n"));
			return False;
		}

		total_smbds = increment_smbd_process_count();
		return total_smbds > lp_max_smbd_processes();
	}
	else
		return False;
}

/****************************************************************************
 Process an smb from the client - split out from the smbd_process() code so
 it can be used by the oplock break code.
****************************************************************************/

void process_smb(char *inbuf, char *outbuf)
{
	static int trans_num;
	int msg_type = CVAL(inbuf,0);
	int32 len = smb_len(inbuf);
	int nread = len + 4;

	DO_PROFILE_INC(smb_count);

	if (trans_num == 0) {
		/* on the first packet, check the global hosts allow/ hosts
		deny parameters before doing any parsing of the packet
		passed to us by the client.  This prevents attacks on our
		parsing code from hosts not in the hosts allow list */
		if (smbd_process_limit() ||
				!check_access(smbd_server_fd(), lp_hostsallow(-1), lp_hostsdeny(-1))) {
			/* send a negative session response "not listening on calling name" */
			static unsigned char buf[5] = {0x83, 0, 0, 1, 0x81};
			DEBUG( 1, ( "Connection denied from %s\n", client_addr() ) );
			(void)send_smb(smbd_server_fd(),(char *)buf);
			exit_server("connection denied");
		}
	}

	DEBUG( 6, ( "got message type 0x%x of len 0x%x\n", msg_type, len ) );
	DEBUG( 3, ( "Transaction %d of length %d\n", trans_num, nread ) );

	if (msg_type == 0)
		show_msg(inbuf);
	else if(msg_type == SMBkeepalive)
		return; /* Keepalive packet. */

	nread = construct_reply(inbuf,outbuf,nread,max_send);
      
	if(nread > 0) {
		if (CVAL(outbuf,0) == 0)
			show_msg(outbuf);
	
		if (nread != smb_len(outbuf) + 4) {
			DEBUG(0,("ERROR: Invalid message response size! %d %d\n",
				nread, smb_len(outbuf)));
		} else if (!send_smb(smbd_server_fd(),outbuf)) {
			exit_server("process_smb: send_smb failed.");
		}
	}
	trans_num++;
}

/****************************************************************************
 Return a string containing the function name of a SMB command.
****************************************************************************/

const char *smb_fn_name(int type)
{
	const char *unknown_name = "SMBunknown";

	if (smb_messages[type].name == NULL)
		return(unknown_name);

	return(smb_messages[type].name);
}

/****************************************************************************
 Helper functions for contruct_reply.
****************************************************************************/

static uint32 common_flags2 = FLAGS2_LONG_PATH_COMPONENTS|FLAGS2_32_BIT_ERROR_CODES;

void add_to_common_flags2(uint32 v)
{
	common_flags2 |= v;
}

void remove_from_common_flags2(uint32 v)
{
	common_flags2 &= ~v;
}

void construct_reply_common(char *inbuf,char *outbuf)
{
	memset(outbuf,'\0',smb_size);

	set_message(outbuf,0,0,True);
	SCVAL(outbuf,smb_com,CVAL(inbuf,smb_com));
	
	memcpy(outbuf+4,inbuf+4,4);
	SCVAL(outbuf,smb_rcls,SMB_SUCCESS);
	SCVAL(outbuf,smb_reh,0);
	SCVAL(outbuf,smb_flg, FLAG_REPLY | (CVAL(inbuf,smb_flg) & FLAG_CASELESS_PATHNAMES)); 
	SSVAL(outbuf,smb_flg2,
		(SVAL(inbuf,smb_flg2) & FLAGS2_UNICODE_STRINGS) |
		common_flags2);

	SSVAL(outbuf,smb_err,SMB_SUCCESS);
	SSVAL(outbuf,smb_tid,SVAL(inbuf,smb_tid));
	SSVAL(outbuf,smb_pid,SVAL(inbuf,smb_pid));
	SSVAL(outbuf,smb_uid,SVAL(inbuf,smb_uid));
	SSVAL(outbuf,smb_mid,SVAL(inbuf,smb_mid));
}

/****************************************************************************
 Construct a chained reply and add it to the already made reply
****************************************************************************/

int chain_reply(char *inbuf,char *outbuf,int size,int bufsize)
{
	static char *orig_inbuf;
	static char *orig_outbuf;
	int smb_com1, smb_com2 = CVAL(inbuf,smb_vwv0);
	unsigned smb_off2 = SVAL(inbuf,smb_vwv1);
	char *inbuf2, *outbuf2;
	int outsize2;
	char inbuf_saved[smb_wct];
	char outbuf_saved[smb_wct];
	int outsize = smb_len(outbuf) + 4;

	/* maybe its not chained */
	if (smb_com2 == 0xFF) {
		SCVAL(outbuf,smb_vwv0,0xFF);
		return outsize;
	}

	if (chain_size == 0) {
		/* this is the first part of the chain */
		orig_inbuf = inbuf;
		orig_outbuf = outbuf;
	}

	/*
	 * The original Win95 redirector dies on a reply to
	 * a lockingX and read chain unless the chain reply is
	 * 4 byte aligned. JRA.
	 */

	outsize = (outsize + 3) & ~3;

	/* we need to tell the client where the next part of the reply will be */
	SSVAL(outbuf,smb_vwv1,smb_offset(outbuf+outsize,outbuf));
	SCVAL(outbuf,smb_vwv0,smb_com2);

	/* remember how much the caller added to the chain, only counting stuff
		after the parameter words */
	chain_size += outsize - smb_wct;

	/* work out pointers into the original packets. The
		headers on these need to be filled in */
	inbuf2 = orig_inbuf + smb_off2 + 4 - smb_wct;
	outbuf2 = orig_outbuf + SVAL(outbuf,smb_vwv1) + 4 - smb_wct;

	/* remember the original command type */
	smb_com1 = CVAL(orig_inbuf,smb_com);

	/* save the data which will be overwritten by the new headers */
	memcpy(inbuf_saved,inbuf2,smb_wct);
	memcpy(outbuf_saved,outbuf2,smb_wct);

	/* give the new packet the same header as the last part of the SMB */
	memmove(inbuf2,inbuf,smb_wct);

	/* create the in buffer */
	SCVAL(inbuf2,smb_com,smb_com2);

	/* create the out buffer */
	construct_reply_common(inbuf2, outbuf2);

	DEBUG(3,("Chained message\n"));
	show_msg(inbuf2);

	/* process the request */
	outsize2 = switch_message(smb_com2,inbuf2,outbuf2,size-chain_size,
				bufsize-chain_size);

	/* copy the new reply and request headers over the old ones, but
		preserve the smb_com field */
	memmove(orig_outbuf,outbuf2,smb_wct);
	SCVAL(orig_outbuf,smb_com,smb_com1);

	/* restore the saved data, being careful not to overwrite any
		data from the reply header */
	memcpy(inbuf2,inbuf_saved,smb_wct);

	{
		int ofs = smb_wct - PTR_DIFF(outbuf2,orig_outbuf);
		if (ofs < 0) ofs = 0;
			memmove(outbuf2+ofs,outbuf_saved+ofs,smb_wct-ofs);
	}

	return outsize2;
}

/****************************************************************************
 Setup the needed select timeout.
****************************************************************************/

static int setup_select_timeout(void)
{
	int select_timeout;
	int t;

	select_timeout = blocking_locks_timeout(SMBD_SELECT_TIMEOUT);
	select_timeout *= 1000;

	t = change_notify_timeout();
	DEBUG(10, ("change_notify_timeout: %d\n", t));
	if (t != -1)
		select_timeout = MIN(select_timeout, t*1000);

	if (print_notify_messages_pending())
		select_timeout = MIN(select_timeout, 1000);

	return select_timeout;
}

/****************************************************************************
 Check if services need reloading.
****************************************************************************/

void check_reload(time_t t)
{
	static pid_t mypid = 0;
	static time_t last_smb_conf_reload_time = 0;
	static time_t last_printer_reload_time = 0;
	time_t printcap_cache_time = (time_t)lp_printcap_cache_time();

	if(last_smb_conf_reload_time == 0) {
		last_smb_conf_reload_time = t;
		/* Our printing subsystem might not be ready at smbd start up.
		   Then no printer is available till the first printers check
		   is performed.  A lower initial interval circumvents this. */
		if ( printcap_cache_time > 60 )
			last_printer_reload_time = t - printcap_cache_time + 60;
		else
			last_printer_reload_time = t;
	}

	if (mypid != getpid()) { /* First time or fork happened meanwhile */
		/* randomize over 60 second the printcap reload to avoid all
		 * process hitting cupsd at the same time */
		int time_range = 60;

		last_printer_reload_time += random() % time_range;
		mypid = getpid();
	}

	if (reload_after_sighup || (t >= last_smb_conf_reload_time+SMBD_RELOAD_CHECK)) {
		reload_services(True);
		reload_after_sighup = False;
		last_smb_conf_reload_time = t;
	}

	/* 'printcap cache time = 0' disable the feature */
	
	if ( printcap_cache_time != 0 )
	{ 
		/* see if it's time to reload or if the clock has been set back */
		
		if ( (t >= last_printer_reload_time+printcap_cache_time) 
			|| (t-last_printer_reload_time  < 0) ) 
		{
			DEBUG( 3,( "Printcap cache time expired.\n"));
			reload_printers();
			last_printer_reload_time = t;
		}
	}
}

/****************************************************************************
 Process any timeout housekeeping. Return False if the caller should exit.
****************************************************************************/

static BOOL timeout_processing(int deadtime, int *select_timeout, time_t *last_timeout_processing_time)
{
	static time_t last_keepalive_sent_time = 0;
	static time_t last_idle_closed_check = 0;
	time_t t;
	BOOL allidle = True;

	if (smb_read_error == READ_EOF) {
		DEBUG(3,("timeout_processing: End of file from client (client has disconnected).\n"));
		return False;
	}

	if (smb_read_error == READ_ERROR) {
		DEBUG(3,("timeout_processing: receive_smb error (%s) Exiting\n",
			strerror(errno)));
		return False;
	}

	if (smb_read_error == READ_BAD_SIG) {
		DEBUG(3,("timeout_processing: receive_smb error bad smb signature. Exiting\n"));
		return False;
	}

	*last_timeout_processing_time = t = time(NULL);

	if(last_keepalive_sent_time == 0)
		last_keepalive_sent_time = t;

	if(last_idle_closed_check == 0)
		last_idle_closed_check = t;

	/* become root again if waiting */
	change_to_root_user();

	/* run all registered idle events */
	smb_run_idle_events(t);

	/* check if we need to reload services */
	check_reload(t);

	/* automatic timeout if all connections are closed */      
	if (conn_num_open()==0 && (t - last_idle_closed_check) >= IDLE_CLOSED_TIMEOUT) {
		DEBUG( 2, ( "Closing idle connection\n" ) );
		return False;
	} else {
		last_idle_closed_check = t;
	}

	if (keepalive && (t - last_keepalive_sent_time)>keepalive) {
		if (!send_keepalive(smbd_server_fd())) {
			DEBUG( 2, ( "Keepalive failed - exiting.\n" ) );
			return False;
		}

		/* send a keepalive for a password server or the like.
			This is attached to the auth_info created in the
		negprot */
		if (negprot_global_auth_context && negprot_global_auth_context->challenge_set_method 
				&& negprot_global_auth_context->challenge_set_method->send_keepalive) {

			negprot_global_auth_context->challenge_set_method->send_keepalive
			(&negprot_global_auth_context->challenge_set_method->private_data);
		}

		last_keepalive_sent_time = t;
	}

	/* check for connection timeouts */
	allidle = conn_idle_all(t, deadtime);

	if (allidle && conn_num_open()>0) {
		DEBUG(2,("Closing idle connection 2.\n"));
		return False;
	}

	if(global_machine_password_needs_changing && 
			/* for ADS we need to do a regular ADS password change, not a domain
					password change */
			lp_security() == SEC_DOMAIN) {

		unsigned char trust_passwd_hash[16];
		time_t lct;

		/*
		 * We're in domain level security, and the code that
		 * read the machine password flagged that the machine
		 * password needs changing.
		 */

		/*
		 * First, open the machine password file with an exclusive lock.
		 */

		if (secrets_lock_trust_account_password(lp_workgroup(), True) == False) {
			DEBUG(0,("process: unable to lock the machine account password for \
machine %s in domain %s.\n", global_myname(), lp_workgroup() ));
			return True;
		}

		if(!secrets_fetch_trust_account_password(lp_workgroup(), trust_passwd_hash, &lct, NULL)) {
			DEBUG(0,("process: unable to read the machine account password for \
machine %s in domain %s.\n", global_myname(), lp_workgroup()));
			secrets_lock_trust_account_password(lp_workgroup(), False);
			return True;
		}

		/*
		 * Make sure someone else hasn't already done this.
		 */

		if(t < lct + lp_machine_password_timeout()) {
			global_machine_password_needs_changing = False;
			secrets_lock_trust_account_password(lp_workgroup(), False);
			return True;
		}

		/* always just contact the PDC here */
    
		change_trust_account_password( lp_workgroup(), NULL);
		global_machine_password_needs_changing = False;
		secrets_lock_trust_account_password(lp_workgroup(), False);
	}

	/*
	 * Check to see if we have any blocking locks
	 * outstanding on the queue.
	 */
	process_blocking_lock_queue(t);

	/* update printer queue caches if necessary */
  
	update_monitored_printq_cache();
  
	/*
	 * Check to see if we have any change notifies 
	 * outstanding on the queue.
	 */
	process_pending_change_notify_queue(t);

	/*
	 * Now we are root, check if the log files need pruning.
	 * Force a log file check.
	 */
	force_check_log_size();
	check_log_size();

	/* Send any queued printer notify message to interested smbd's. */

	print_notify_send_messages(0);

	/*
	 * Modify the select timeout depending upon
	 * what we have remaining in our queues.
	 */

	*select_timeout = setup_select_timeout();

	return True;
}

/****************************************************************************
 Accessor functions for InBuffer, OutBuffer.
****************************************************************************/

char *get_InBuffer(void)
{
	return InBuffer;
}

void set_InBuffer(char *new_inbuf)
{
	InBuffer = new_inbuf;
	current_inbuf = InBuffer;
}

char *get_OutBuffer(void)
{
	return OutBuffer;
}

void set_OutBuffer(char *new_outbuf)
{
	OutBuffer = new_outbuf;
}

/****************************************************************************
 Free an InBuffer. Checks if not in use by aio system.
 Must have been allocated by NewInBuffer.
****************************************************************************/

void free_InBuffer(char *inbuf)
{
	if (!aio_inbuffer_in_use(inbuf)) {
		if (current_inbuf == inbuf) {
			current_inbuf = NULL;
		}
		SAFE_FREE(inbuf);
	}
}

/****************************************************************************
 Free an OutBuffer. No outbuffers currently stolen by aio system.
 Must have been allocated by NewInBuffer.
****************************************************************************/

void free_OutBuffer(char *outbuf)
{
	SAFE_FREE(outbuf);
}

const int total_buffer_size = (BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE + SAFETY_MARGIN);

/****************************************************************************
 Allocate a new InBuffer. Returns the new and old ones.
****************************************************************************/

char *NewInBuffer(char **old_inbuf)
{
	char *new_inbuf = (char *)SMB_MALLOC(total_buffer_size);
	if (!new_inbuf) {
		return NULL;
	}
	if (old_inbuf) {
		*old_inbuf = InBuffer;
	}
	InBuffer = new_inbuf;
#if defined(DEVELOPER)
	clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, InBuffer, total_buffer_size);
#endif
	return InBuffer;
}

/****************************************************************************
 Allocate a new OutBuffer. Returns the new and old ones.
****************************************************************************/

char *NewOutBuffer(char **old_outbuf)
{
	char *new_outbuf = (char *)SMB_MALLOC(total_buffer_size);
	if (!new_outbuf) {
		return NULL;
	}
	if (old_outbuf) {
		*old_outbuf = OutBuffer;
	}
	OutBuffer = new_outbuf;
#if defined(DEVELOPER)
	clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, OutBuffer, total_buffer_size);
#endif
	return OutBuffer;
}

/****************************************************************************
 Process commands from the client
****************************************************************************/

void smbd_process(void)
{
	time_t last_timeout_processing_time = time(NULL);
	unsigned int num_smbs = 0;

	/* Allocate the primary Inbut/Output buffers. */

	if ((NewInBuffer(NULL) == NULL) || (NewOutBuffer(NULL) == NULL)) 
		return;

	max_recv = MIN(lp_maxxmit(),BUFFER_SIZE);

	while (True) {
		int deadtime = lp_deadtime()*60;
		int select_timeout = setup_select_timeout();
		int num_echos;

		if (deadtime <= 0)
			deadtime = DEFAULT_SMBD_TIMEOUT;

		errno = 0;      
		
		/* free up temporary memory */
		lp_talloc_free();
		main_loop_talloc_free();

		/* Did someone ask for immediate checks on things like blocking locks ? */
		if (select_timeout == 0) {
			if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
				return;
			num_smbs = 0; /* Reset smb counter. */
		}

		run_events();

#if defined(DEVELOPER)
		clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, InBuffer, total_buffer_size);
#endif

		while (!receive_message_or_smb(InBuffer,BUFFER_SIZE+LARGE_WRITEX_HDR_SIZE,select_timeout)) {
			if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
				return;
			num_smbs = 0; /* Reset smb counter. */
		}

		/*
		 * Ensure we do timeout processing if the SMB we just got was
		 * only an echo request. This allows us to set the select
		 * timeout in 'receive_message_or_smb()' to any value we like
		 * without worrying that the client will send echo requests
		 * faster than the select timeout, thus starving out the
		 * essential processing (change notify, blocking locks) that
		 * the timeout code does. JRA.
		 */ 
		num_echos = smb_echo_count;

		clobber_region(SAFE_STRING_FUNCTION_NAME, SAFE_STRING_LINE, OutBuffer, total_buffer_size);

		process_smb(InBuffer, OutBuffer);

		if (smb_echo_count != num_echos) {
			if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
				return;
			num_smbs = 0; /* Reset smb counter. */
		}

		num_smbs++;

		/*
		 * If we are getting smb requests in a constant stream
		 * with no echos, make sure we attempt timeout processing
		 * every select_timeout milliseconds - but only check for this
		 * every 200 smb requests.
		 */
		
		if ((num_smbs % 200) == 0) {
			time_t new_check_time = time(NULL);
			if(new_check_time - last_timeout_processing_time >= (select_timeout/1000)) {
				if(!timeout_processing( deadtime, &select_timeout, &last_timeout_processing_time))
					return;
				num_smbs = 0; /* Reset smb counter. */
				last_timeout_processing_time = new_check_time; /* Reset time. */
			}
		}

		/* The timeout_processing function isn't run nearly
		   often enough to implement 'max log size' without
		   overrunning the size of the file by many megabytes.
		   This is especially true if we are running at debug
		   level 10.  Checking every 50 SMBs is a nice
		   tradeoff of performance vs log file size overrun. */

		if ((num_smbs % 50) == 0 && need_to_check_log_size()) {
			change_to_root_user();
			check_log_size();
		}
	}
}