2 * Definitions for packet disassembly structures and routines
6 * Wireshark - Network traffic analyzer
7 * By Gerald Combs <gerald@wireshark.org>
8 * Copyright 1998 Gerald Combs
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version 2
13 * of the License, or (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
28 #include "wiretap/wtap.h"
33 #include "value_string.h"
34 #include "column_info.h"
35 #include "frame_data.h"
36 #include "packet_info.h"
37 #include "column-utils.h"
43 #endif /* __cplusplus */
45 #define hi_nibble(b) (((b) & 0xf0) >> 4)
46 #define lo_nibble(b) ((b) & 0x0f)
48 /* Useful when you have an array whose size you can tell at compile-time */
49 #define array_length(x) (sizeof x / sizeof x[0])
51 /* Check whether the "len" bytes of data starting at "offset" is
52 * entirely inside the captured data for this packet. */
53 #define BYTES_ARE_IN_FRAME(offset, captured_len, len) \
54 ((guint)(offset) + (guint)(len) > (guint)(offset) && \
55 (guint)(offset) + (guint)(len) <= (guint)(captured_len))
57 /* To pass one of two strings, singular or plural */
58 #define plurality(d,s,p) ((d) == 1 ? (s) : (p))
60 typedef struct _packet_counts {
77 /** Number of packet counts. */
78 #define PACKET_COUNTS_SIZE sizeof(packet_counts) / sizeof (gint)
80 /* Types of character encodings */
82 PACKET_CHAR_ENC_CHAR_ASCII = 0, /* ASCII */
83 PACKET_CHAR_ENC_CHAR_EBCDIC = 1 /* EBCDIC */
86 extern void packet_init(void);
87 extern void packet_cleanup(void);
89 /* Handle for dissectors you call directly or register with "dissector_add_uint()".
90 This handle is opaque outside of "packet.c". */
91 struct dissector_handle;
92 typedef struct dissector_handle *dissector_handle_t;
94 /* Hash table for matching unsigned integers, or strings, and dissectors;
95 this is opaque outside of "packet.c". */
96 struct dissector_table;
97 typedef struct dissector_table *dissector_table_t;
100 * Dissector that returns nothing.
102 typedef void (*dissector_t)(tvbuff_t *, packet_info *, proto_tree *);
105 * Dissector that returns:
107 * The amount of data in the protocol's PDU, if it was able to
108 * dissect all the data;
110 * 0, if the tvbuff doesn't contain a PDU for that protocol;
112 * The negative of the amount of additional data needed, if
113 * we need more data (e.g., from subsequent TCP segments) to
114 * dissect the entire PDU.
116 typedef int (*new_dissector_t)(tvbuff_t *, packet_info *, proto_tree *);
118 /** Type of a heuristic dissector, used in heur_dissector_add().
120 * @param tvb the tv_buff with the (remaining) packet data
121 * @param pinfo the packet info of this packet (additional info)
122 * @param tree the protocol tree to be build or NULL
123 * @return TRUE if the packet was recognized by the sub-dissector (stop dissection here)
125 typedef gboolean (*heur_dissector_t)(tvbuff_t *tvb, packet_info *pinfo,
128 typedef void (*DATFunc) (const gchar *table_name, ftenum_t selector_type,
129 gpointer key, gpointer value, gpointer user_data);
130 typedef void (*DATFunc_handle) (const gchar *table_name, gpointer value,
132 typedef void (*DATFunc_table) (const gchar *table_name, const gchar *ui_name,
135 typedef void (*DATFunc_heur_table) (const gchar *table_name,gpointer table,
138 /* Opaque structure - provides type checking but no access to components */
139 typedef struct dtbl_entry dtbl_entry_t;
141 extern dissector_handle_t dtbl_entry_get_handle (dtbl_entry_t *dtbl_entry);
142 extern dissector_handle_t dtbl_entry_get_initial_handle (dtbl_entry_t * entry);
143 extern void dissector_table_foreach_changed (const char *name, DATFunc func,
145 extern void dissector_table_foreach (const char *name, DATFunc func,
147 extern void dissector_all_tables_foreach_changed (DATFunc func,
149 extern void dissector_table_foreach_handle(const char *name, DATFunc_handle func,
151 extern void dissector_all_tables_foreach_table (DATFunc_table func,
154 /* a protocol uses the function to register a sub-dissector table */
155 extern dissector_table_t register_dissector_table(const char *name,
156 const char *ui_name, const ftenum_t type, const int base);
158 /* Find a dissector table by table name. */
159 extern dissector_table_t find_dissector_table(const char *name);
161 /* Get the UI name for a sub-dissector table, given its internal name */
162 extern const char *get_dissector_table_ui_name(const char *name);
164 /* Get the field type for values of the selector for a dissector table,
165 given the table's internal name */
166 extern ftenum_t get_dissector_table_selector_type(const char *name);
168 /* Get the base to use when displaying values of the selector for a
169 sub-dissector table, given the table's internal name */
170 extern int get_dissector_table_base(const char *name);
172 /* Add an entry to a uint dissector table. */
173 extern void dissector_add_uint(const char *abbrev, const guint32 pattern,
174 dissector_handle_t handle);
176 /* For old code that hasn't yet been changed. */
177 #define dissector_add(abbrev, pattern, handle) \
178 dissector_add_uint(abbrev, pattern, handle)
180 /* Delete the entry for a dissector in a uint dissector table
181 with a particular pattern. */
182 extern void dissector_delete_uint(const char *name, const guint32 pattern,
183 dissector_handle_t handle);
185 /* For old code that hasn't yet been changed. */
186 #define dissector_delete(name, pattern, handle) \
187 dissector_delete_uint(name, pattern, handle)
189 /* Change the entry for a dissector in a uint dissector table
190 with a particular pattern to use a new dissector handle. */
191 extern void dissector_change_uint(const char *abbrev, const guint32 pattern,
192 dissector_handle_t handle);
194 /* For old code that hasn't yet been changed. */
195 #define dissector_change(abbrev, pattern, handle) \
196 dissector_change_uint(abbrev, pattern, handle)
198 /* Reset an entry in a uint dissector table to its initial value. */
199 extern void dissector_reset_uint(const char *name, const guint32 pattern);
201 /* For old code that hasn't yet been changed. */
202 #define dissector_reset(name, pattern) \
203 dissector_reset_uint(name, pattern)
205 /* Look for a given value in a given uint dissector table and, if found,
206 call the dissector with the arguments supplied, and return TRUE,
207 otherwise return FALSE. */
208 extern gboolean dissector_try_uint(dissector_table_t sub_dissectors,
209 const guint32 uint_val, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
211 /* For old code that hasn't yet been changed. */
212 #define dissector_try_port(sub_dissectors, uint_val, tvb, pinfo, tree) \
213 dissector_try_uint(sub_dissectors, uint_val, tvb, pinfo, tree)
215 /* Look for a given value in a given uint dissector table and, if found,
216 call the dissector with the arguments supplied, and return TRUE,
217 otherwise return FALSE. */
218 extern gboolean dissector_try_uint_new(dissector_table_t sub_dissectors,
219 const guint32 uint_val, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, const gboolean add_proto_name);
221 /* For old code that hasn't yet been changed. */
222 #define dissector_try_port_new(sub_dissectors, uint_val, tvb, pinfo, tree, add_proto_name) \
223 dissector_try_uint_new(sub_dissectors, uint_val, tvb, pinfo, tree, add_proto_name)
225 /* Look for a given value in a given uint dissector table and, if found,
226 return the dissector handle for that value. */
227 extern dissector_handle_t dissector_get_uint_handle(
228 dissector_table_t const sub_dissectors, const guint32 uint_val);
230 /* For old code that hasn't yet been changed. */
231 #define dissector_get_port_handle(sub_dissectors, uint_val) \
232 dissector_get_uint_handle(sub_dissectors, uint_val)
234 /* Add an entry to a string dissector table. */
235 extern void dissector_add_string(const char *name, const gchar *pattern,
236 dissector_handle_t handle);
238 /* Delete the entry for a dissector in a string dissector table
239 with a particular pattern. */
240 extern void dissector_delete_string(const char *name, const gchar *pattern,
241 dissector_handle_t handle);
243 /* Change the entry for a dissector in a string dissector table
244 with a particular pattern to use a new dissector handle. */
245 extern void dissector_change_string(const char *name, const gchar *pattern,
246 dissector_handle_t handle);
248 /* Reset an entry in a string sub-dissector table to its initial value. */
249 extern void dissector_reset_string(const char *name, const gchar *pattern);
251 /* Look for a given string in a given dissector table and, if found, call
252 the dissector with the arguments supplied, and return TRUE, otherwise
254 extern gboolean dissector_try_string(dissector_table_t sub_dissectors,
255 const gchar *string, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
257 /* Look for a given value in a given string dissector table and, if found,
258 return the dissector handle for that value. */
259 extern dissector_handle_t dissector_get_string_handle(
260 dissector_table_t sub_dissectors, const gchar *string);
262 /* Add a handle to the list of handles that *could* be used with this
263 table. That list is used by code in the UI. */
264 extern void dissector_add_handle(const char *name, dissector_handle_t handle);
266 /* List of "heuristic" dissectors (which get handed a packet, look at it,
267 and either recognize it as being for their protocol, dissect it, and
268 return TRUE, or don't recognize it and return FALSE) to be called
269 by another dissector. */
270 typedef GSList *heur_dissector_list_t;
274 heur_dissector_t dissector;
275 protocol_t *protocol;
279 /** A protocol uses this function to register a heuristic sub-dissector list.
280 * Call this in the parent dissectors proto_register function.
282 * @param name the name of this protocol
283 * @param list the list of heuristic sub-dissectors to be registered
285 extern void register_heur_dissector_list(const char *name,
286 heur_dissector_list_t *list);
288 extern void dissector_all_heur_tables_foreach_table (DATFunc_heur_table func,
291 /** Try all the dissectors in a given heuristic dissector list. This is done,
292 * until we find one that recognizes the protocol.
293 * Call this while the parent dissector running.
295 * @param sub_dissectors the sub-dissector list
296 * @param tvb the tv_buff with the (remaining) packet data
297 * @param pinfo the packet info of this packet (additional info)
298 * @param tree the protocol tree to be build or NULL
299 * @return TRUE if the packet was recognized by the sub-dissector (stop dissection here)
301 extern gboolean dissector_try_heuristic(heur_dissector_list_t sub_dissectors,
302 tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
304 /** Add a sub-dissector to a heuristic dissector list.
305 * Call this in the proto_handoff function of the sub-dissector.
307 * @param name the name of the "parent" protocol, e.g. "tcp"
308 * @param dissector the sub-dissector to be registered
309 * @param proto the protocol id of the sub-dissector
311 extern void heur_dissector_add(const char *name, heur_dissector_t dissector,
314 /** Remove a sub-dissector from a heuristic dissector list.
315 * Call this in the prefs_reinit function of the sub-dissector.
317 * @param name the name of the "parent" protocol, e.g. "tcp"
318 * @param dissector the sub-dissector to be unregistered
319 * @param proto the protocol id of the sub-dissector
321 extern void heur_dissector_delete(const char *name, heur_dissector_t dissector, const int proto);
323 /** Enable/Disable a sub-dissector in a heuristic dissector list
324 * Call this in the prefs_reinit function of the sub-dissector.
326 * @param name the name of the "parent" protocol, e.g. "tcp"
327 * @param dissector the sub-dissector to be disabled/enabled
328 * @param proto the protocol id of the sub-dissector
329 * @param TRUE/FALSE to enable/disable the sub-dissector
331 extern void heur_dissector_set_enabled(const char *name, heur_dissector_t dissector, const int proto, const gboolean enabled);
333 /* Register a dissector. */
334 extern void register_dissector(const char *name, dissector_t dissector,
336 extern void new_register_dissector(const char *name, new_dissector_t dissector,
339 /* Get the long name of the protocol for a dissector handle. */
340 extern const char *dissector_handle_get_long_name(const dissector_handle_t handle);
342 /* Get the short name of the protocol for a dissector handle. */
343 extern const char *dissector_handle_get_short_name(const dissector_handle_t handle);
345 /* Get the index of the protocol for a dissector handle. */
346 extern int dissector_handle_get_protocol_index(const dissector_handle_t handle);
348 /* Find a dissector by name. */
349 extern dissector_handle_t find_dissector(const char *name);
351 /* Create an anonymous handle for a dissector. */
352 extern dissector_handle_t create_dissector_handle(dissector_t dissector,
354 extern dissector_handle_t new_create_dissector_handle(new_dissector_t dissector,
357 /* Call a dissector through a handle and if no dissector was found
358 * pass if over to the "data" dissector instead.
360 * @param handle The dissector to call.
361 * @param tvb The buffer to dissect.
362 * @param pinfo Packet Info.
363 * @param tree The protocol tree.
364 * @return If the protocol for that handle isn't enabled call the data
365 * dissector. Otherwise, if the handle refers to a new-style
366 * dissector, call the dissector and return its return value, otherwise call
367 * it and return the length of the tvbuff pointed to by the argument.
369 extern int call_dissector(dissector_handle_t handle, tvbuff_t *tvb,
370 packet_info *pinfo, proto_tree *tree);
372 /* Call a dissector through a handle but if no dissector was found
373 * just return 0 and do not call the "data" dissector instead.
375 * @param handle The dissector to call.
376 * @param tvb The buffer to dissect.
377 * @param pinfo Packet Info.
378 * @param tree The protocol tree.
379 * @return If the protocol for that handle isn't enabled, return 0 without
380 * calling the dissector. Otherwise, if the handle refers to a new-style
381 * dissector, call the dissector and return its return value, otherwise call
382 * it and return the length of the tvbuff pointed to by the argument.
384 extern int call_dissector_only(dissector_handle_t handle, tvbuff_t *tvb,
385 packet_info *pinfo, proto_tree *tree);
387 /* Do all one-time initialization. */
388 extern void dissect_init(void);
390 extern void dissect_cleanup(void);
393 * Given a tvbuff, and a length from a packet header, adjust the length
394 * of the tvbuff to reflect the specified length.
396 extern void set_actual_length(tvbuff_t *tvb, const guint specified_len);
398 /* Allow protocols to register "init" routines, which are called before
399 we make a pass through a capture file and dissect all its packets
400 (e.g., when we read in a new capture file, or run a "filter packets"
401 or "colorize packets" pass over the current capture file). */
402 extern void register_init_routine(void (*func)(void));
404 /* Initialize all data structures used for dissection. */
405 extern void init_dissection(void);
407 /* Free data structures allocated for dissection. */
408 extern void cleanup_dissection(void);
410 /* Allow protocols to register a "cleanup" routine to be
411 * run after the initial sequential run through the packets.
412 * Note that the file can still be open after this; this is not
413 * the final cleanup. */
414 extern void register_postseq_cleanup_routine(void (*func)(void));
416 /* Call all the registered "postseq_cleanup" routines. */
417 extern void postseq_cleanup_all_protocols(void);
419 /* Allow dissectors to register a "final_registration" routine
420 * that is run like the proto_register_XXX() routine, but the end
421 * end of the epan_init() function; that is, *after* all other
422 * subsystems, liked dfilters, have finished initializing. This is
423 * useful for dissector registration routines which need to compile
424 * display filters. dfilters can't initialize itself until all protocols
425 * have registereed themselvs. */
427 register_final_registration_routine(void (*func)(void));
429 /* Call all the registered "final_registration" routines. */
431 final_registration_all_protocols(void);
434 * Add a new data source to the list of data sources for a frame, given
435 * the tvbuff for the data source and its name.
437 extern void add_new_data_source(packet_info *pinfo, tvbuff_t *tvb,
441 * Return the data source name.
443 extern const char* get_data_source_name(data_source *src);
446 * Free up a frame's list of data sources.
448 extern void free_data_sources(packet_info *pinfo);
451 * Dissectors should never modify the packet data.
453 extern void dissect_packet(epan_dissect_t *edt,
454 union wtap_pseudo_header *pseudo_header, const guchar *pd,
455 frame_data *fd, column_info *cinfo);
457 /* These functions are in packet-ethertype.c */
458 extern void capture_ethertype(guint16 etype, const guchar *pd, int offset,
459 int len, packet_counts *ld);
460 extern void ethertype(guint16 etype, tvbuff_t *tvb, int offset_after_ethertype,
461 packet_info *pinfo, proto_tree *tree, proto_tree *fh_tree,
462 int etype_id, int trailer_id, int fcs_len);
465 * Dump layer/selector/dissector records in a fashion similar to the
466 * proto_registrar_dump_* routines.
468 extern void dissector_dump_decodes(void);
471 * For each heuristic dissector table, dump list of dissectors (filter_names) for that table
473 extern void dissector_dump_heur_decodes(void);
476 * post dissectors are to be called by packet-frame.c after every other
477 * dissector has been called.
479 extern void register_postdissector(dissector_handle_t);
480 extern gboolean have_postdissector(void);
481 extern void call_all_postdissectors(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
485 #endif /* __cplusplus */
487 #endif /* packet.h */