aboutsummaryrefslogtreecommitdiffstats
path: root/epan/packet.c
blob: 5e3c350c4afe0c71f3ca6ee766a4c8df6f12c521 (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
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
/* packet.c
 * Routines for packet disassembly
 *
 * $Id$
 *
 * Ethereal - Network traffic analyzer
 * By Gerald Combs <gerald@ethereal.com>
 * Copyright 1998 Gerald Combs
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <glib.h>

#include <stdio.h>
#include <stdlib.h>

#ifdef HAVE_STDARG_H
#include <stdarg.h>
#endif

#include <string.h>
#include <ctype.h>
#include <time.h>

#include "packet.h"
#include "timestamp.h"

#include "atalk-utils.h"
#include "sna-utils.h"
#include "osi-utils.h"
#include "to_str.h"

#include "addr_resolv.h"
#include "tvbuff.h"
#include "plugins.h"
#include "epan_dissect.h"
#include "emem.h"

#include <epan/reassemble.h>
#include <epan/stream.h>

static gint proto_malformed = -1;
static dissector_handle_t frame_handle = NULL;
static dissector_handle_t data_handle = NULL;

const true_false_string flags_set_truth = {
  "Set",
  "Not set"
};

void
packet_init(void)
{
  frame_handle = find_dissector("frame");
  data_handle = find_dissector("data");
  proto_malformed = proto_get_id_by_filter_name("malformed");
}

void
packet_cleanup(void)
{
	/* nothing */
}

/*
 * Given a tvbuff, and a length from a packet header, adjust the length
 * of the tvbuff to reflect the specified length.
 */
void
set_actual_length(tvbuff_t *tvb, guint specified_len)
{
  if (specified_len < tvb_reported_length(tvb)) {
    /* Adjust the length of this tvbuff to include only the specified
       payload length.

       The dissector above the one calling us (the dissector above is
       probably us) may use that to determine how much of its packet
       was padding. */
    tvb_set_reported_length(tvb, specified_len);
  }
}

/* Allow protocols to register "init" routines, which are called before
   we make a pass through a capture file and dissect all its packets
   (e.g., when we read in a new capture file, or run a "filter packets"
   or "colorize packets" pass over the current capture file). */
static GSList *init_routines;

void
register_init_routine(void (*func)(void))
{
	init_routines = g_slist_append(init_routines, (gpointer)func);
}

typedef void (*void_func_t)(void);

/* Initialize all data structures used for dissection. */
static void
call_init_routine(gpointer routine, gpointer dummy _U_)
{
	void_func_t func = (void_func_t)routine;
	(*func)();
}

/*
 * XXX - for now, these are the same; the "init" routines free whatever
 * stuff is left over from any previous dissection, and then initialize
 * their tables.
 *
 * We should probably split that into "init" and "cleanup" routines, for
 * cleanliness' sake.
 */
void
init_dissection(void)
{
	/* Reclaim and reinitialize all memory of seasonal scope */
	se_free_all();

	/* Initialize the table of conversations. */
	epan_conversation_init();

	/* Initialize the table of circuits. */
	epan_circuit_init();

	/* Initialize protocol-specific variables. */
	g_slist_foreach(init_routines, &call_init_routine, NULL);

	/* Initialize the common data structures for fragment reassembly.
	   Must be done *after* calling init routines, as those routines
	   may free up space for fragments, which they find by using the
	   data structures that "reassemble_init()" frees. */
	reassemble_init();

	/* Initialise the stream-handling tables */
	stream_init();
}

void
cleanup_dissection(void)
{
	init_dissection();
}

/* Allow protocols to register a "cleanup" routine to be
 * run after the initial sequential run through the packets.
 * Note that the file can still be open after this; this is not
 * the final cleanup. */
static GSList *postseq_cleanup_routines;

void
register_postseq_cleanup_routine(void_func_t func)
{
	postseq_cleanup_routines = g_slist_append(postseq_cleanup_routines,
			(gpointer)func);
}

/* Call all the registered "postseq_cleanup" routines. */
static void
call_postseq_cleanup_routine(gpointer routine, gpointer dummy _U_)
{
	void_func_t func = (void_func_t)routine;
	(*func)();
}

void
postseq_cleanup_all_protocols(void)
{
	g_slist_foreach(postseq_cleanup_routines,
			&call_postseq_cleanup_routine, NULL);
}

/*
 * Add a new data source to the list of data sources for a frame, given
 * the tvbuff for the data source and its name.
 */
void
add_new_data_source(packet_info *pinfo, tvbuff_t *tvb, const char *name)
{
	data_source *src;

	src = ep_alloc(sizeof (data_source));
	src->tvb = tvb;
	/*
	 * XXX - if we require this argument to be a string constant,
	 * we don't need to allocate a buffer for a copy and make a
	 * copy, and wouldn't need to free the buffer, either.
	 */
	src->name = ep_strdup_printf("%s (%u bytes)", name, tvb_length(tvb));
	pinfo->data_src = g_slist_append(pinfo->data_src, src);
}

/*
 * Free up a frame's list of data sources.
 */
void
free_data_sources(packet_info *pinfo)
{
	g_slist_free(pinfo->data_src);
	pinfo->data_src = NULL;
}

/* Allow dissectors to register a "final_registration" routine
 * that is run like the proto_register_XXX() routine, but at the
 * end of the epan_init() function; that is, *after* all other
 * subsystems, like dfilters, have finished initializing. This is
 * useful for dissector registration routines which need to compile
 * display filters. dfilters can't initialize itself until all protocols
 * have registered themselves. */
static GSList *final_registration_routines;

void
register_final_registration_routine(void (*func)(void))
{
	final_registration_routines = g_slist_append(final_registration_routines,
			(gpointer)func);
}

/* Call all the registered "final_registration" routines. */
static void
call_final_registration_routine(gpointer routine, gpointer dummy _U_)
{
	void_func_t func = (void_func_t)routine;

	(*func)();
}

void
final_registration_all_protocols(void)
{
	g_slist_foreach(final_registration_routines,
			&call_final_registration_routine, NULL);
}


/* Creates the top-most tvbuff and calls dissect_frame() */
void
dissect_packet(epan_dissect_t *edt, union wtap_pseudo_header *pseudo_header,
	       const guchar *pd, frame_data *fd, column_info *cinfo)
{
	if (cinfo != NULL)
		col_init(cinfo);
	edt->pi.current_proto = "<Missing Protocol Name>";
	edt->pi.cinfo = cinfo;
	edt->pi.fd = fd;
	edt->pi.pseudo_header = pseudo_header;
	edt->pi.data_src = NULL;
	edt->pi.dl_src.type = AT_NONE;
	edt->pi.dl_src.len = 0;
	edt->pi.dl_src.data = NULL;
	edt->pi.dl_dst.type = AT_NONE;
	edt->pi.dl_dst.len = 0;
	edt->pi.dl_dst.data = NULL;
	edt->pi.net_src.type = AT_NONE;
	edt->pi.net_src.len = 0;
	edt->pi.net_src.data = NULL;
	edt->pi.net_dst.type = AT_NONE;
	edt->pi.net_dst.len = 0;
	edt->pi.net_dst.data = NULL;
	edt->pi.src.type = AT_NONE;
	edt->pi.src.len = 0;
	edt->pi.src.data = NULL;
	edt->pi.dst.type = AT_NONE;
	edt->pi.dst.len = 0;
	edt->pi.dst.data = NULL;
	edt->pi.ethertype = 0;
	edt->pi.ipproto  = 0;
	edt->pi.ipxptype = 0;
	edt->pi.ctype = CT_NONE;
	edt->pi.circuit_id = 0;
	edt->pi.noreassembly_reason = "";
	edt->pi.fragmented = FALSE;
	edt->pi.in_error_pkt = FALSE;
	edt->pi.ptype = PT_NONE;
	edt->pi.srcport  = 0;
	edt->pi.destport = 0;
	edt->pi.match_port = 0;
	edt->pi.match_string = NULL;
	edt->pi.can_desegment = 0;
	edt->pi.want_pdu_tracking = 0;
	edt->pi.p2p_dir = P2P_DIR_UNKNOWN;
	edt->pi.private_data = NULL;
	edt->pi.oxid = 0;
	edt->pi.rxid = 0;
	edt->pi.r_ctl = 0;
	edt->pi.src_idx = 0;
	edt->pi.dst_idx = 0;
	edt->pi.vsan = 0;
	edt->pi.dcectxid = 0;
	edt->pi.dcetransporttype = -1;
	edt->pi.decrypt_gssapi_tvb = 0;
	edt->pi.gssapi_wrap_tvb = NULL;
	edt->pi.gssapi_encrypted_tvb = NULL;
	edt->pi.gssapi_decrypted_tvb = NULL;
	edt->pi.layer_names = NULL;
	edt->pi.link_number = 0;
	edt->pi.annex_a_used = MTP2_ANNEX_A_USED_UNKNOWN;

	TRY {
		edt->tvb = tvb_new_real_data(pd, fd->cap_len, fd->pkt_len);
		/* Add this tvbuffer into the data_src list */
		add_new_data_source(&edt->pi, edt->tvb, "Frame");

		/* Even though dissect_frame() catches all the exceptions a
		 * sub-dissector can throw, dissect_frame() itself may throw
		 * a ReportedBoundsError in bizarre cases. Thus, we catch the exception
		 * in this function. */
		if(frame_handle != NULL)
		  call_dissector(frame_handle, edt->tvb, &edt->pi, edt->tree);

	}
	CATCH(BoundsError) {
		g_assert_not_reached();
	}
	CATCH(ReportedBoundsError) {
		if(proto_malformed != -1){
			proto_tree_add_protocol_format(edt->tree, proto_malformed, edt->tvb, 0, 0,
			                               "[Malformed Frame: Packet Length]" );
		} else {
			g_assert_not_reached();
		}
	}
	ENDTRY;

	fd->flags.visited = 1;
}

/*********************** code added for sub-dissector lookup *********************/

/*
 * An dissector handle.
 */
struct dissector_handle {
	const char	*name;		/* dissector name */
	gboolean	is_new;		/* TRUE if new-style dissector */
	union {
		dissector_t	old;
		new_dissector_t	new;
	} dissector;
	protocol_t	*protocol;
};

/* This function will return
 * old style dissector :
 *   length of the payload or 1 of the payload is empty
 * new dissector :
 *   >0  this protocol was successfully dissected and this was this protocol.
 *   0   this packet did not match this protocol.
 *
 * The only time this function will return 0 is if it is a new style dissector
 * and if the dissector rejected the packet.
 */
static int
call_dissector_through_handle(dissector_handle_t handle, tvbuff_t *tvb,
    packet_info *pinfo, proto_tree *tree)
{
	const char *saved_proto;
	int ret;

	saved_proto = pinfo->current_proto;

	if (handle->protocol != NULL) {
		pinfo->current_proto =
		    proto_get_protocol_short_name(handle->protocol);
	}

	if (handle->is_new) {
		ret = (*handle->dissector.new)(tvb, pinfo, tree);
	} else {
		(*handle->dissector.old)(tvb, pinfo, tree);
		ret = tvb_length(tvb);
		if (ret == 0) {
			/*
			 * XXX - a tvbuff can have 0 bytes of data in
			 * it, so we have to make sure we don't return
			 * 0.
			 */
			ret = 1;
		}
	}

	pinfo->current_proto = saved_proto;

	return ret;
}

/*
 * Call a dissector through a handle.
 * If the protocol for that handle isn't enabled, return 0 without
 * calling the dissector.
 * Otherwise, if the handle refers to a new-style dissector, call the
 * dissector and return its return value, otherwise call it and return
 * the length of the tvbuff pointed to by the argument.
 */
static int
call_dissector_work(dissector_handle_t handle, tvbuff_t *tvb,
    packet_info *pinfo_arg, proto_tree *tree)
{
	packet_info *volatile pinfo = pinfo_arg;
	const char *saved_proto;
	guint16 saved_can_desegment;
	volatile int ret = 0;
	gboolean save_writable;
	volatile address save_dl_src;
	volatile address save_dl_dst;
	volatile address save_net_src;
	volatile address save_net_dst;
	volatile address save_src;
	volatile address save_dst;
	volatile gint saved_layer_names_len = 0;

	if (handle->protocol != NULL &&
	    !proto_is_protocol_enabled(handle->protocol)) {
		/*
		 * The protocol isn't enabled.
		 */
		return 0;
	}

	saved_proto = pinfo->current_proto;
	saved_can_desegment = pinfo->can_desegment;

	if (pinfo->layer_names != NULL)
		saved_layer_names_len = pinfo->layer_names->len;

	/*
	 * can_desegment is set to 2 by anyone which offers the
	 * desegmentation api/service.
	 * Then everytime a subdissector is called it is decremented
	 * by one.
	 * Thus only the subdissector immediately on top of whoever
	 * offers this service can use it.
	 * We save the current value of "can_desegment" for the
	 * benefit of TCP proxying dissectors such as SOCKS, so they
	 * can restore it and allow the dissectors they call to use
	 * the desegmentation service.
	 */
	pinfo->saved_can_desegment = saved_can_desegment;
	pinfo->can_desegment = saved_can_desegment-(saved_can_desegment>0);
	if (handle->protocol != NULL) {
		pinfo->current_proto =
		    proto_get_protocol_short_name(handle->protocol);

		/*
		 * Add the protocol name to the layers
		 */
		if (pinfo->layer_names) {
			if (pinfo->layer_names->len > 0)
				g_string_append(pinfo->layer_names, ":");
			g_string_append(pinfo->layer_names,
			    proto_get_protocol_filter_name(proto_get_id(handle->protocol)));
		}
	}

	if (pinfo->in_error_pkt) {
		/*
		 * This isn't a packet being transported inside
		 * the protocol whose dissector is calling us,
		 * it's a copy of a packet that caused an error
		 * in some protocol included in a packet that
		 * reports the error (e.g., an ICMP Unreachable
		 * packet).
		 */

		/*
		 * Save the current state of the writability of
		 * the columns, and restore them after the
		 * dissector returns, so that the columns
		 * don't reflect the packet that got the error,
		 * they reflect the packet that reported the
		 * error.
		 */
		save_writable = col_get_writable(pinfo->cinfo);
		col_set_writable(pinfo->cinfo, FALSE);
	 	save_dl_src = pinfo->dl_src;
		save_dl_dst = pinfo->dl_dst;
		save_net_src = pinfo->net_src;
		save_net_dst = pinfo->net_dst;
		save_src = pinfo->src;
		save_dst = pinfo->dst;

		/* Dissect the contained packet. */
		TRY {
			ret = call_dissector_through_handle(handle, tvb,
			    pinfo, tree);
		}
		CATCH(BoundsError) {
			/*
			 * Restore the column writability and addresses.
			 */
			col_set_writable(pinfo->cinfo, save_writable);
			pinfo->dl_src = save_dl_src;
			pinfo->dl_dst = save_dl_dst;
			pinfo->net_src = save_net_src;
			pinfo->net_dst = save_net_dst;
			pinfo->src = save_src;
			pinfo->dst = save_dst;

			/*
			 * Restore the current protocol, so any
			 * "Short Frame" indication reflects that
			 * protocol, not the protocol for the
			 * packet that got the error.
			 */
			pinfo->current_proto = saved_proto;

			/*
			 * Restore the desegmentability state.
			 */
			pinfo->can_desegment = saved_can_desegment;

			/*
			 * Rethrow the exception, so this will be
			 * reported as a short frame.
			 */
			RETHROW;
		}
		CATCH(ReportedBoundsError) {
			/*
			 * "ret" wasn't set because an exception was thrown
			 * before "call_dissector_through_handle()" returned.
			 * As it called something, at least one dissector
			 * accepted the packet, and, as an exception was
			 * thrown, not only was all the tvbuff dissected,
			 * a dissector tried dissecting past the end of
			 * the data in some tvbuff, so we'll assume that
			 * the entire tvbuff was dissected.
			 */
			ret = tvb_length(tvb);
		}
		ENDTRY;

		col_set_writable(pinfo->cinfo, save_writable);
		pinfo->dl_src = save_dl_src;
		pinfo->dl_dst = save_dl_dst;
		pinfo->net_src = save_net_src;
		pinfo->net_dst = save_net_dst;
		pinfo->src = save_src;
		pinfo->dst = save_dst;
		pinfo->want_pdu_tracking = 0;
	} else {
		/*
		 * Just call the subdissector.
		 */
		ret = call_dissector_through_handle(handle, tvb, pinfo, tree);
	}

	if (ret == 0) {
		/*
		 * That dissector didn't accept the packet, so
		 * remove its protocol's name from the list
		 * of protocols.
		 */
		if (pinfo->layer_names != NULL) {
			g_string_truncate(pinfo->layer_names,
			    saved_layer_names_len);
		}
	}
	pinfo->current_proto = saved_proto;
	pinfo->can_desegment = saved_can_desegment;
	return ret;
}

/*
 * An entry in the hash table portion of a dissector table.
 */
struct dtbl_entry {
	dissector_handle_t initial;
	dissector_handle_t current;
};

/*
 * A dissector table.
 *
 * "hash_table" is a hash table, indexed by port number, supplying
 * a "struct dtbl_entry"; it records what dissector is assigned to
 * that port number in that table.
 *
 * "dissector_handles" is a list of all dissectors that *could* be
 * used in that table; not all of them are necessarily in the table,
 * as they may be for protocols that don't have a fixed port number.
 *
 * "ui_name" is the name the dissector table has in the user interface.
 *
 * "type" is a field type giving the width of the port number for that
 * dissector table.
 *
 * "base" is the base in which to display the port number for that
 * dissector table.
 */
struct dissector_table {
	GHashTable	*hash_table;
	GSList		*dissector_handles;
	const char	*ui_name;
	ftenum_t	type;
	int		base;
};

static GHashTable *dissector_tables = NULL;

/* Finds a dissector table by table name. */
dissector_table_t
find_dissector_table(const char *name)
{
	g_assert(dissector_tables);
	return g_hash_table_lookup( dissector_tables, name );
}

/* Find an entry in a uint dissector table. */
static dtbl_entry_t *
find_uint_dtbl_entry(dissector_table_t sub_dissectors, guint32 pattern)
{
	switch (sub_dissectors->type) {

	case FT_UINT8:
	case FT_UINT16:
	case FT_UINT24:
	case FT_UINT32:
		/*
		 * You can do a port lookup in these tables.
		 */
		break;

	default:
		/*
		 * But you can't do a port lookup in any other types
		 * of tables.
		 */
		g_assert_not_reached();
	}

	/*
	 * Find the entry.
	 */
	return g_hash_table_lookup(sub_dissectors->hash_table,
	    GUINT_TO_POINTER(pattern));
}

/* Add an entry to a uint dissector table. */
void
dissector_add(const char *name, guint32 pattern, dissector_handle_t handle)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity checks */
	g_assert( sub_dissectors);
	switch (sub_dissectors->type) {

	case FT_UINT8:
	case FT_UINT16:
	case FT_UINT24:
	case FT_UINT32:
		/*
		 * You can do a port lookup in these tables.
		 */
		break;

	default:
		/*
		 * But you can't do a port lookup in any other types
		 * of tables.
		 */
		g_assert_not_reached();
	}

	dtbl_entry = g_malloc(sizeof (dtbl_entry_t));
	dtbl_entry->current = handle;
	dtbl_entry->initial = dtbl_entry->current;

/* do the table insertion */
    	g_hash_table_insert( sub_dissectors->hash_table,
    	    GUINT_TO_POINTER( pattern), (gpointer)dtbl_entry);

	/*
	 * Now add it to the list of handles that could be used with this
	 * table, because it *is* being used with this table.
	 */
	dissector_add_handle(name, handle);
}

/* Delete the entry for a dissector in a uint dissector table
   with a particular pattern. */

/* NOTE: this doesn't use the dissector call variable. It is included to */
/*	be consistant with the dissector_add and more importantly to be used */
/*	if the technique of adding a temporary dissector is implemented.  */
/*	If temporary dissectors are deleted, then the original dissector must */
/*	be available. */
void
dissector_delete(const char *name, guint32 pattern,
	dissector_handle_t handle _U_)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	/*
	 * Find the entry.
	 */
	dtbl_entry = find_uint_dtbl_entry(sub_dissectors, pattern);

	if (dtbl_entry != NULL) {
		/*
		 * Found - remove it.
		 */
		g_hash_table_remove(sub_dissectors->hash_table,
		    GUINT_TO_POINTER(pattern));

		/*
		 * Now free up the entry.
		 */
		g_free(dtbl_entry);
	}
}

/* Change the entry for a dissector in a uint dissector table
   with a particular pattern to use a new dissector handle. */
void
dissector_change(const char *name, guint32 pattern, dissector_handle_t handle)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	/*
	 * See if the entry already exists. If so, reuse it.
	 */
	dtbl_entry = find_uint_dtbl_entry(sub_dissectors, pattern);
	if (dtbl_entry != NULL) {
	  dtbl_entry->current = handle;
	  return;
	}

	/*
	 * Don't create an entry if there is no dissector handle - I.E. the
	 * user said not to decode something that wasn't being decoded
	 * in the first place.
	 */
	if (handle == NULL)
	  return;

	dtbl_entry = g_malloc(sizeof (dtbl_entry_t));
	dtbl_entry->initial = NULL;
	dtbl_entry->current = handle;

/* do the table insertion */
    	g_hash_table_insert( sub_dissectors->hash_table,
    	    GUINT_TO_POINTER( pattern), (gpointer)dtbl_entry);
}

/* Reset an entry in a uint dissector table to its initial value. */
void
dissector_reset(const char *name, guint32 pattern)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	/*
	 * Find the entry.
	 */
	dtbl_entry = find_uint_dtbl_entry(sub_dissectors, pattern);

	if (dtbl_entry == NULL)
		return;

	/*
	 * Found - is there an initial value?
	 */
	if (dtbl_entry->initial != NULL) {
		dtbl_entry->current = dtbl_entry->initial;
	} else {
		g_hash_table_remove(sub_dissectors->hash_table,
		    GUINT_TO_POINTER(pattern));
		g_free(dtbl_entry);
	}
}

/* Look for a given value in a given uint dissector table and, if found,
   call the dissector with the arguments supplied, and return TRUE,
   otherwise return FALSE. */
gboolean
dissector_try_port(dissector_table_t sub_dissectors, guint32 port,
    tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	dtbl_entry_t *dtbl_entry;
	struct dissector_handle *handle;
	guint32 saved_match_port;
	int ret;

	dtbl_entry = find_uint_dtbl_entry(sub_dissectors, port);
	if (dtbl_entry != NULL) {
		/*
		 * Is there currently a dissector handle for this entry?
		 */
		handle = dtbl_entry->current;
		if (handle == NULL) {
			/*
			 * No - pretend this dissector didn't exist,
			 * so that other dissectors might have a chance
			 * to dissect this packet.
			 */
			return FALSE;
		}

		/*
		 * Save the current value of "pinfo->match_port",
		 * set it to the port that matched, call the
		 * dissector, and restore "pinfo->match_port".
		 */
		saved_match_port = pinfo->match_port;
		pinfo->match_port = port;
		ret = call_dissector_work(handle, tvb, pinfo, tree);
		pinfo->match_port = saved_match_port;

		/*
		 * If a new-style dissector returned 0, it means that
		 * it didn't think this tvbuff represented a packet for
		 * its protocol, and didn't dissect anything.
		 *
		 * Old-style dissectors can't reject the packet.
		 *
		 * 0 is also returned if the protocol wasn't enabled.
		 *
		 * If the packet was rejected, we return FALSE, so that
		 * other dissectors might have a chance to dissect this
		 * packet, otherwise we return TRUE.
		 */
		return ret != 0;
	}
	return FALSE;
}

/* Look for a given value in a given uint dissector table and, if found,
   return the dissector handle for that value. */
dissector_handle_t
dissector_get_port_handle(dissector_table_t sub_dissectors, guint32 port)
{
	dtbl_entry_t *dtbl_entry;

	dtbl_entry = find_uint_dtbl_entry(sub_dissectors, port);
	if (dtbl_entry != NULL)
		return dtbl_entry->current;
	else
		return NULL;
}

/* Find an entry in a string dissector table. */
static dtbl_entry_t *
find_string_dtbl_entry(dissector_table_t sub_dissectors, const gchar *pattern)
{
	switch (sub_dissectors->type) {

	case FT_STRING:
	case FT_STRINGZ:
		/*
		 * You can do a string lookup in these tables.
		 */
		break;

	default:
		/*
		 * But you can't do a string lookup in any other types
		 * of tables.
		 */
		g_assert_not_reached();
	}

	/*
	 * Find the entry.
	 */
	return g_hash_table_lookup(sub_dissectors->hash_table, pattern);
}

/* Add an entry to a string dissector table. */
void
dissector_add_string(const char *name, const gchar *pattern,
    dissector_handle_t handle)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	switch (sub_dissectors->type) {

	case FT_STRING:
	case FT_STRINGZ:
		/*
		 * You can do a string lookup in these tables.
		 */
		break;

	default:
		/*
		 * But you can't do a string lookup in any other types
		 * of tables.
		 */
		g_assert_not_reached();
	}

	dtbl_entry = g_malloc(sizeof (dtbl_entry_t));
	dtbl_entry->current = handle;
	dtbl_entry->initial = dtbl_entry->current;

/* do the table insertion */
    	g_hash_table_insert( sub_dissectors->hash_table, (gpointer)pattern,
    	    (gpointer)dtbl_entry);

	/*
	 * Now add it to the list of handles that could be used with this
	 * table, because it *is* being used with this table.
	 */
	dissector_add_handle(name, handle);
}

/* Delete the entry for a dissector in a string dissector table
   with a particular pattern. */

/* NOTE: this doesn't use the dissector call variable. It is included to */
/*	be consistant with the dissector_add_string and more importantly to */
/*      be used if the technique of adding a temporary dissector is */
/*      implemented.  */
/*	If temporary dissectors are deleted, then the original dissector must */
/*	be available. */
void
dissector_delete_string(const char *name, const gchar *pattern,
	dissector_handle_t handle _U_)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	/*
	 * Find the entry.
	 */
	dtbl_entry = find_string_dtbl_entry(sub_dissectors, pattern);

	if (dtbl_entry != NULL) {
		/*
		 * Found - remove it.
		 */
		g_hash_table_remove(sub_dissectors->hash_table, pattern);

		/*
		 * Now free up the entry.
		 */
		g_free(dtbl_entry);
	}
}

/* Change the entry for a dissector in a string dissector table
   with a particular pattern to use a new dissector handle. */
void
dissector_change_string(const char *name, gchar *pattern,
    dissector_handle_t handle)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	/*
	 * See if the entry already exists. If so, reuse it.
	 */
	dtbl_entry = find_string_dtbl_entry(sub_dissectors, pattern);
	if (dtbl_entry != NULL) {
	  dtbl_entry->current = handle;
	  return;
	}

	/*
	 * Don't create an entry if there is no dissector handle - I.E. the
	 * user said not to decode something that wasn't being decoded
	 * in the first place.
	 */
	if (handle == NULL)
	  return;

	dtbl_entry = g_malloc(sizeof (dtbl_entry_t));
	dtbl_entry->initial = NULL;
	dtbl_entry->current = handle;

/* do the table insertion */
    	g_hash_table_insert( sub_dissectors->hash_table, pattern,
    	    (gpointer)dtbl_entry);
}

/* Reset an entry in a string sub-dissector table to its initial value. */
void
dissector_reset_string(const char *name, const gchar *pattern)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	dtbl_entry_t *dtbl_entry;

/* sanity check */
	g_assert( sub_dissectors);

	/*
	 * Find the entry.
	 */
	dtbl_entry = find_string_dtbl_entry(sub_dissectors, pattern);

	if (dtbl_entry == NULL)
		return;

	/*
	 * Found - is there an initial value?
	 */
	if (dtbl_entry->initial != NULL) {
		dtbl_entry->current = dtbl_entry->initial;
	} else {
		g_hash_table_remove(sub_dissectors->hash_table, pattern);
		g_free(dtbl_entry);
	}
}

/* Look for a given string in a given dissector table and, if found, call
   the dissector with the arguments supplied, and return TRUE, otherwise
   return FALSE. */
gboolean
dissector_try_string(dissector_table_t sub_dissectors, const gchar *string,
    tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	dtbl_entry_t *dtbl_entry;
	struct dissector_handle *handle;
	int ret;
	const gchar *saved_match_string;

	dtbl_entry = find_string_dtbl_entry(sub_dissectors, string);
	if (dtbl_entry != NULL) {
		/*
		 * Is there currently a dissector handle for this entry?
		 */
		handle = dtbl_entry->current;
		if (handle == NULL) {
			/*
			 * No - pretend this dissector didn't exist,
			 * so that other dissectors might have a chance
			 * to dissect this packet.
			 */
			return FALSE;
		}

		/*
		 * Save the current value of "pinfo->match_string",
		 * set it to the string that matched, call the
		 * dissector, and restore "pinfo->match_string".
		 */
		saved_match_string = pinfo->match_string;
		pinfo->match_string = string;
		ret = call_dissector_work(handle, tvb, pinfo, tree);
		pinfo->match_string = saved_match_string;

		/*
		 * If a new-style dissector returned 0, it means that
		 * it didn't think this tvbuff represented a packet for
		 * its protocol, and didn't dissect anything.
		 *
		 * Old-style dissectors can't reject the packet.
		 *
		 * 0 is also returned if the protocol wasn't enabled.
		 *
		 * If the packet was rejected, we return FALSE, so that
		 * other dissectors might have a chance to dissect this
		 * packet, otherwise we return TRUE.
		 */
		return ret != 0;
	}
	return FALSE;
}

/* Look for a given value in a given string dissector table and, if found,
   return the dissector handle for that value. */
dissector_handle_t
dissector_get_string_handle(dissector_table_t sub_dissectors,
    const gchar *string)
{
	dtbl_entry_t *dtbl_entry;

	dtbl_entry = find_string_dtbl_entry(sub_dissectors, string);
	if (dtbl_entry != NULL)
		return dtbl_entry->current;
	else
		return NULL;
}

dissector_handle_t
dtbl_entry_get_handle (dtbl_entry_t *dtbl_entry)
{
	return dtbl_entry->current;
}

/* Add a handle to the list of handles that *could* be used with this
   table.  That list is used by code in the UI. */
void
dissector_add_handle(const char *name, dissector_handle_t handle)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	GSList *entry;

	/* sanity check */
	g_assert(sub_dissectors != NULL);

	/* Is it already in this list? */
	entry = g_slist_find(sub_dissectors->dissector_handles, (gpointer)handle);
	if (entry != NULL) {
		/*
		 * Yes - don't insert it again.
		 */
		return;
	}

	/* Add it to the list. */
	sub_dissectors->dissector_handles =
	    g_slist_append(sub_dissectors->dissector_handles, (gpointer)handle);
}

dissector_handle_t
dtbl_entry_get_initial_handle (dtbl_entry_t *dtbl_entry)
{
	return dtbl_entry->initial;
}

/**************************************************/
/*                                                */
/*       Routines to walk dissector tables        */
/*                                                */
/**************************************************/

typedef struct dissector_foreach_info {
  gpointer     caller_data;
  DATFunc      caller_func;
  GHFunc       next_func;
  gchar       *table_name;
  ftenum_t     selector_type;
} dissector_foreach_info_t;

/*
 * Called for each entry in a dissector table.
 */
static void
dissector_table_foreach_func (gpointer key, gpointer value, gpointer user_data)
{
	dissector_foreach_info_t *info;
	dtbl_entry_t *dtbl_entry;

	g_assert(value);
	g_assert(user_data);

	dtbl_entry = value;
	if (dtbl_entry->current == NULL ||
	    dtbl_entry->current->protocol == NULL) {
		/*
		 * Either there is no dissector for this entry, or
		 * the dissector doesn't have a protocol associated
		 * with it.
		 *
		 * XXX - should the latter check be done?
		 */
		return;
	}

	info = user_data;
	info->caller_func(info->table_name, info->selector_type, key, value,
	    info->caller_data);
}

/*
 * Called for each entry in the table of all dissector tables.
 */
static void
dissector_all_tables_foreach_func (gpointer key, gpointer value, gpointer user_data)
{
	dissector_table_t sub_dissectors;
	dissector_foreach_info_t *info;

	g_assert(value);
	g_assert(user_data);

	sub_dissectors = value;
	info = user_data;
	info->table_name = (gchar*) key;
	info->selector_type = get_dissector_table_selector_type(info->table_name);
	g_hash_table_foreach(sub_dissectors->hash_table, info->next_func, info);
}

/*
 * Walk all dissector tables calling a user supplied function on each
 * entry.
 */
static void
dissector_all_tables_foreach (DATFunc func,
			      gpointer user_data)
{
	dissector_foreach_info_t info;

	info.caller_data = user_data;
	info.caller_func = func;
	info.next_func = dissector_table_foreach_func;
	g_hash_table_foreach(dissector_tables, dissector_all_tables_foreach_func, &info);
}

/*
 * Walk one dissector table's hash table calling a user supplied function
 * on each entry.
 */
void
dissector_table_foreach (char *name,
			 DATFunc func,
			 gpointer user_data)
{
	dissector_foreach_info_t info;
	dissector_table_t sub_dissectors = find_dissector_table( name);

	info.table_name = name;
	info.selector_type = sub_dissectors->type;
	info.caller_func = func;
	info.caller_data = user_data;
	g_hash_table_foreach(sub_dissectors->hash_table, dissector_table_foreach_func, &info);
}

/*
 * Walk one dissector table's list of handles calling a user supplied
 * function on each entry.
 */
void
dissector_table_foreach_handle(const char *name,
			       DATFunc_handle func,
			       gpointer user_data)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);
	GSList *tmp;

	for (tmp = sub_dissectors->dissector_handles; tmp != NULL;
	    tmp = g_slist_next(tmp))
		func(name, tmp->data, user_data);
}

/*
 * Called for each entry in a dissector table.
 */
static void
dissector_table_foreach_changed_func (gpointer key, gpointer value, gpointer user_data)
{
	dtbl_entry_t *dtbl_entry;
	dissector_foreach_info_t *info;

	g_assert(value);
	g_assert(user_data);

	dtbl_entry = value;
	if (dtbl_entry->initial == dtbl_entry->current) {
		/*
		 * Entry hasn't changed - don't call the function.
		 */
		return;
	}

	info = user_data;
	info->caller_func(info->table_name, info->selector_type, key, value,
	    info->caller_data);
}

/*
 * Walk all dissector tables calling a user supplied function only on
 * any entry that has been changed from its original state.
 */
void
dissector_all_tables_foreach_changed (DATFunc func,
				      gpointer user_data)
{
	dissector_foreach_info_t info;

	info.caller_data = user_data;
	info.caller_func = func;
	info.next_func = dissector_table_foreach_changed_func;
	g_hash_table_foreach(dissector_tables, dissector_all_tables_foreach_func, &info);
}

/*
 * Walk one dissector table calling a user supplied function only on
 * any entry that has been changed from its original state.
 */
void
dissector_table_foreach_changed (char *name,
				 DATFunc func,
				 gpointer user_data)
{
	dissector_foreach_info_t info;
	dissector_table_t sub_dissectors = find_dissector_table( name);

	info.table_name = name;
	info.selector_type = sub_dissectors->type;
	info.caller_func = func;
	info.caller_data = user_data;
	g_hash_table_foreach(sub_dissectors->hash_table,
	    dissector_table_foreach_changed_func, &info);
}

typedef struct dissector_foreach_table_info {
  gpointer      caller_data;
  DATFunc_table caller_func;
} dissector_foreach_table_info_t;

/*
 * Called for each entry in the table of all dissector tables.
 */
static void
dissector_all_tables_foreach_table_func (gpointer key, gpointer value, gpointer user_data)
{
	dissector_table_t table;
	dissector_foreach_table_info_t *info;

	table = value;
	info = user_data;
	(*info->caller_func)((gchar*)key, table->ui_name, info->caller_data);
}

/*
 * Walk all dissector tables calling a user supplied function on each
 * table.
 */
void
dissector_all_tables_foreach_table (DATFunc_table func,
				    gpointer user_data)
{
	dissector_foreach_table_info_t info;

	info.caller_data = user_data;
	info.caller_func = func;
	g_hash_table_foreach(dissector_tables, dissector_all_tables_foreach_table_func, &info);
}

dissector_table_t
register_dissector_table(const char *name, const char *ui_name, ftenum_t type,
    int base)
{
	dissector_table_t	sub_dissectors;

	/* Create our hash-of-hashes if it doesn't already exist */
	if (!dissector_tables) {
		dissector_tables = g_hash_table_new( g_str_hash, g_str_equal );
		g_assert(dissector_tables);
	}

	/* Make sure the registration is unique */
	g_assert(!g_hash_table_lookup( dissector_tables, name ));

	/* Create and register the dissector table for this name; returns */
	/* a pointer to the dissector table. */
	sub_dissectors = g_malloc(sizeof (struct dissector_table));
	switch (type) {

	case FT_UINT8:
	case FT_UINT16:
	case FT_UINT24:
	case FT_UINT32:
		/*
		 * XXX - there's no "g_uint_hash()" or "g_uint_equal()",
		 * so we use "g_direct_hash()" and "g_direct_equal()".
		 */
		sub_dissectors->hash_table = g_hash_table_new( g_direct_hash,
		    g_direct_equal );
		break;

	case FT_STRING:
	case FT_STRINGZ:
		sub_dissectors->hash_table = g_hash_table_new( g_str_hash,
		    g_str_equal );
		break;

	default:
		g_assert_not_reached();
	}
	sub_dissectors->dissector_handles = NULL;
	sub_dissectors->ui_name = ui_name;
	sub_dissectors->type = type;
	sub_dissectors->base = base;
	g_hash_table_insert( dissector_tables, (gpointer)name, (gpointer) sub_dissectors );
	return sub_dissectors;
}

const char *
get_dissector_table_ui_name(const char *name)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);

	return sub_dissectors->ui_name;
}

ftenum_t
get_dissector_table_selector_type(const char *name)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);

	return sub_dissectors->type;
}

int
get_dissector_table_base(const char *name)
{
	dissector_table_t sub_dissectors = find_dissector_table( name);

	return sub_dissectors->base;
}

static GHashTable *heur_dissector_lists = NULL;

typedef struct {
	heur_dissector_t dissector;
	protocol_t *protocol;
} heur_dtbl_entry_t;

/* Finds a heuristic dissector table by field name. */
static heur_dissector_list_t *
find_heur_dissector_list(const char *name)
{
	g_assert(heur_dissector_lists != NULL);
	return g_hash_table_lookup(heur_dissector_lists, name);
}

void
heur_dissector_add(const char *name, heur_dissector_t dissector, int proto)
{
	heur_dissector_list_t *sub_dissectors = find_heur_dissector_list(name);
	heur_dtbl_entry_t *dtbl_entry;

	/* sanity check */
	g_assert(sub_dissectors != NULL);

	dtbl_entry = g_malloc(sizeof (heur_dtbl_entry_t));
	dtbl_entry->dissector = dissector;
	dtbl_entry->protocol = find_protocol_by_id(proto);

	/* do the table insertion */
	*sub_dissectors = g_slist_append(*sub_dissectors, (gpointer)dtbl_entry);
}

gboolean
dissector_try_heuristic(heur_dissector_list_t sub_dissectors,
    tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	gboolean status;
	const char *saved_proto;
	GSList *entry;
	heur_dtbl_entry_t *dtbl_entry;
	guint16 saved_can_desegment;
	gint saved_layer_names_len = 0;

	/* can_desegment is set to 2 by anyone which offers this api/service.
	   then everytime a subdissector is called it is decremented by one.
	   thus only the subdissector immediately ontop of whoever offers this
	   service can use it.
	   We save the current value of "can_desegment" for the
	   benefit of TCP proxying dissectors such as SOCKS, so they
	   can restore it and allow the dissectors they call to use
	   the desegmentation service.
	*/
	saved_can_desegment=pinfo->can_desegment;
	pinfo->saved_can_desegment = saved_can_desegment;
	pinfo->can_desegment = saved_can_desegment-(saved_can_desegment>0);

	status = FALSE;
	saved_proto = pinfo->current_proto;

	if (pinfo->layer_names != NULL)
		saved_layer_names_len = pinfo->layer_names->len;

	for (entry = sub_dissectors; entry != NULL; entry = g_slist_next(entry)) {
		/* XXX - why set this now and above? */
		pinfo->can_desegment = saved_can_desegment-(saved_can_desegment>0);
		dtbl_entry = (heur_dtbl_entry_t *)entry->data;

		if (dtbl_entry->protocol != NULL &&
		    !proto_is_protocol_enabled(dtbl_entry->protocol)) {
			/*
			 * No - don't try this dissector.
			 */
			continue;
		}

		if (dtbl_entry->protocol != NULL) {
			pinfo->current_proto =
			    proto_get_protocol_short_name(dtbl_entry->protocol);

			/*
			 * Add the protocol name to the layers; we'll remove it
			 * if the dissector fails.
			 */
			if (pinfo->layer_names) {
				if (pinfo->layer_names->len > 0)
					g_string_append(pinfo->layer_names, ":");
				g_string_append(pinfo->layer_names,
					proto_get_protocol_filter_name(proto_get_id(dtbl_entry->protocol)));
			}
		}

		if ((*dtbl_entry->dissector)(tvb, pinfo, tree)) {
			status = TRUE;
			break;
		} else {
			/*
			 * That dissector didn't accept the packet, so
			 * remove its protocol's name from the list
			 * of protocols.
			 */
			if (pinfo->layer_names != NULL) {
				g_string_truncate(pinfo->layer_names,
				    saved_layer_names_len);
			}
		}
	}
	pinfo->current_proto = saved_proto;
	pinfo->can_desegment=saved_can_desegment;
	return status;
}

void
register_heur_dissector_list(const char *name, heur_dissector_list_t *sub_dissectors)
{
	/* Create our hash-of-lists if it doesn't already exist */
	if (heur_dissector_lists == NULL) {
		heur_dissector_lists = g_hash_table_new(g_str_hash, g_str_equal);
		g_assert(heur_dissector_lists != NULL);
	}

	/* Make sure the registration is unique */
	g_assert(g_hash_table_lookup(heur_dissector_lists, name) == NULL);

	*sub_dissectors = NULL;	/* initially empty */
	g_hash_table_insert(heur_dissector_lists, (gpointer)name,
	    (gpointer) sub_dissectors);
}

/*
 * Register dissectors by name; used if one dissector always calls a
 * particular dissector, or if it bases the decision of which dissector
 * to call on something other than a numerical value or on "try a bunch
 * of dissectors until one likes the packet".
 */

/*
 * List of registered dissectors.
 */
static GHashTable *registered_dissectors = NULL;

/* Get the short name of the protocol for a dissector handle, if it has
   a protocol. */
const char *
dissector_handle_get_short_name(dissector_handle_t handle)
{
	if (handle->protocol == NULL) {
		/*
		 * No protocol (see, for example, the handle for
		 * dissecting the set of protocols where the first
		 * octet of the payload is an OSI network layer protocol
		 * ID).
		 */
		return NULL;
	}
	return proto_get_protocol_short_name(handle->protocol);
}

/* Get the index of the protocol for a dissector handle, if it has
   a protocol. */
int
dissector_handle_get_protocol_index(dissector_handle_t handle)
{
	if (handle->protocol == NULL) {
		/*
		 * No protocol (see, for example, the handle for
		 * dissecting the set of protocols where the first
		 * octet of the payload is an OSI network layer protocol
		 * ID).
		 */
		return -1;
	}
	return proto_get_id(handle->protocol);
}

/* Find a registered dissector by name. */
dissector_handle_t
find_dissector(const char *name)
{
	g_assert(registered_dissectors != NULL);
	return g_hash_table_lookup(registered_dissectors, name);
}

/* Create an anonymous handle for a dissector. */
dissector_handle_t
create_dissector_handle(dissector_t dissector, int proto)
{
	struct dissector_handle *handle;

	handle = g_malloc(sizeof (struct dissector_handle));
	handle->name = NULL;
	handle->is_new = FALSE;
	handle->dissector.old = dissector;
	handle->protocol = find_protocol_by_id(proto);

	return handle;
}

dissector_handle_t
new_create_dissector_handle(new_dissector_t dissector, int proto)
{
	struct dissector_handle *handle;

	handle = g_malloc(sizeof (struct dissector_handle));
	handle->name = NULL;
	handle->is_new = TRUE;
	handle->dissector.new = dissector;
	handle->protocol = find_protocol_by_id(proto);

	return handle;
}

/* Register a dissector by name. */
void
register_dissector(const char *name, dissector_t dissector, int proto)
{
	struct dissector_handle *handle;

	/* Create our hash table if it doesn't already exist */
	if (registered_dissectors == NULL) {
		registered_dissectors = g_hash_table_new(g_str_hash, g_str_equal);
		g_assert(registered_dissectors != NULL);
	}

	/* Make sure the registration is unique */
	g_assert(g_hash_table_lookup(registered_dissectors, name) == NULL);

	handle = g_malloc(sizeof (struct dissector_handle));
	handle->name = name;
	handle->is_new = FALSE;
	handle->dissector.old = dissector;
	handle->protocol = find_protocol_by_id(proto);

	g_hash_table_insert(registered_dissectors, (gpointer)name,
	    (gpointer) handle);
}

void
new_register_dissector(const char *name, new_dissector_t dissector, int proto)
{
	struct dissector_handle *handle;

	/* Create our hash table if it doesn't already exist */
	if (registered_dissectors == NULL) {
		registered_dissectors = g_hash_table_new(g_str_hash, g_str_equal);
		g_assert(registered_dissectors != NULL);
	}

	/* Make sure the registration is unique */
	g_assert(g_hash_table_lookup(registered_dissectors, name) == NULL);

	handle = g_malloc(sizeof (struct dissector_handle));
	handle->name = name;
	handle->is_new = TRUE;
	handle->dissector.new = dissector;
	handle->protocol = find_protocol_by_id(proto);

	g_hash_table_insert(registered_dissectors, (gpointer)name,
	    (gpointer) handle);
}

/* Call a dissector through a handle and if this fails call the "data"
 * dissector.
 */
int
call_dissector(dissector_handle_t handle, tvbuff_t *tvb,
    packet_info *pinfo, proto_tree *tree)
{
	int ret;

	ret = call_dissector_work(handle, tvb, pinfo, tree);
	if (ret == 0) {
		/*
		 * The protocol was disabled, or the dissector rejected
		 * it.  Just dissect this packet as data.
		 */
	        g_assert(data_handle != NULL);
		g_assert(data_handle->protocol != NULL);
		call_dissector(data_handle, tvb, pinfo, tree);
		return tvb_length(tvb);
	}
	return ret;
}

/* Call a dissector through a handle but if the dissector rejected it
 * return 0 instead of using the default "data" dissector.
 */
int
call_dissector_only(dissector_handle_t handle, tvbuff_t *tvb,
    packet_info *pinfo, proto_tree *tree)
{
	int ret;

	ret = call_dissector_work(handle, tvb, pinfo, tree);
	return ret;
}

/*
 * Dumps the "layer type"/"decode as" associations to stdout, similar
 * to the proto_registrar_dump_*() routines.
 *
 * There is one record per line. The fields are tab-delimited.
 *
 * Field 1 = layer type, e.g. "tcp.port"
 * Field 2 = selector in decimal
 * Field 3 = "decode as" name, e.g. "http"
 */


static void
dissector_dump_decodes_display(gchar *table_name, ftenum_t selector_type _U_,
    gpointer key, gpointer value, gpointer user_data _U_)
{
	guint32 selector = (guint32) key;
	dissector_table_t sub_dissectors = find_dissector_table(table_name);
	dtbl_entry_t *dtbl_entry;
	dissector_handle_t handle;
	gint proto_id;
	const gchar *decode_as;

	g_assert(sub_dissectors);
	switch (sub_dissectors->type) {

		case FT_UINT8:
		case FT_UINT16:
		case FT_UINT24:
		case FT_UINT32:
			dtbl_entry = value;
			g_assert(dtbl_entry);

			handle = dtbl_entry->current;
			g_assert(handle);

			proto_id = dissector_handle_get_protocol_index(handle);

			if (proto_id != -1) {
				decode_as = proto_get_protocol_filter_name(proto_id);
				g_assert(decode_as != NULL);
				printf("%s\t%u\t%s\n", table_name, selector, decode_as);
			}
			break;

	default:
		break;
	}
}

void
dissector_dump_decodes() {
	dissector_all_tables_foreach(dissector_dump_decodes_display, NULL);
}

static GPtrArray* post_dissectors = NULL;
static guint num_of_postdissectors = 0;

void register_postdissector(dissector_handle_t handle) {
    if (!post_dissectors)
        post_dissectors = g_ptr_array_new();

    g_ptr_array_add(post_dissectors, handle);
    num_of_postdissectors++;
}

extern void call_all_postdissectors(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
    guint i;
    for(i=0;i<num_of_postdissectors;i++) {
        call_dissector((dissector_handle_t) g_ptr_array_index(post_dissectors,i),
                       tvb,pinfo,tree);
    }
}