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"
31 #include "wsutil/pint.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"
40 #include "ws_symbol_export.h"
45 #endif /* __cplusplus */
47 /** @defgroup packet General Packet Dissection
52 #define hi_nibble(b) (((b) & 0xf0) >> 4)
53 #define lo_nibble(b) ((b) & 0x0f)
55 /* Useful when you have an array whose size you can tell at compile-time */
56 #define array_length(x) (sizeof x / sizeof x[0])
58 /* Check whether the "len" bytes of data starting at "offset" is
59 * entirely inside the captured data for this packet. */
60 #define BYTES_ARE_IN_FRAME(offset, captured_len, len) \
61 ((guint)(offset) + (guint)(len) > (guint)(offset) && \
62 (guint)(offset) + (guint)(len) <= (guint)(captured_len))
64 /* To pass one of two strings, singular or plural */
65 #define plurality(d,s,p) ((d) == 1 ? (s) : (p))
67 typedef struct _packet_counts {
84 /** Number of packet counts. */
85 #define PACKET_COUNTS_SIZE sizeof(packet_counts) / sizeof (gint)
87 extern void packet_init(void);
88 extern void packet_cache_proto_handles(void);
89 extern void packet_cleanup(void);
91 /* Handle for dissectors you call directly or register with "dissector_add_uint()".
92 This handle is opaque outside of "packet.c". */
93 struct dissector_handle;
94 typedef struct dissector_handle *dissector_handle_t;
96 /* Hash table for matching unsigned integers, or strings, and dissectors;
97 this is opaque outside of "packet.c". */
98 struct dissector_table;
99 typedef struct dissector_table *dissector_table_t;
102 * Dissector that returns nothing.
104 typedef void (*dissector_t)(tvbuff_t *, packet_info *, proto_tree *);
107 * Dissector that returns:
109 * The amount of data in the protocol's PDU, if it was able to
110 * dissect all the data;
112 * 0, if the tvbuff doesn't contain a PDU for that protocol;
114 * The negative of the amount of additional data needed, if
115 * we need more data (e.g., from subsequent TCP segments) to
116 * dissect the entire PDU.
118 typedef int (*new_dissector_t)(tvbuff_t *, packet_info *, proto_tree *, void *);
120 /** Type of a heuristic dissector, used in heur_dissector_add().
122 * @param tvb the tvbuff with the (remaining) packet data
123 * @param pinfo the packet info of this packet (additional info)
124 * @param tree the protocol tree to be build or NULL
125 * @return TRUE if the packet was recognized by the sub-dissector (stop dissection here)
127 typedef gboolean (*heur_dissector_t)(tvbuff_t *tvb, packet_info *pinfo,
128 proto_tree *tree, void *);
130 typedef void (*DATFunc) (const gchar *table_name, ftenum_t selector_type,
131 gpointer key, gpointer value, gpointer user_data);
132 typedef void (*DATFunc_handle) (const gchar *table_name, gpointer value,
134 typedef void (*DATFunc_table) (const gchar *table_name, const gchar *ui_name,
137 typedef void (*DATFunc_heur_table) (const gchar *table_name,gpointer table,
140 /* Opaque structure - provides type checking but no access to components */
141 typedef struct dtbl_entry dtbl_entry_t;
143 WS_DLL_PUBLIC dissector_handle_t dtbl_entry_get_handle (dtbl_entry_t *dtbl_entry);
144 WS_DLL_PUBLIC dissector_handle_t dtbl_entry_get_initial_handle (dtbl_entry_t * entry);
145 void dissector_table_foreach_changed (const char *name, DATFunc func,
147 WS_DLL_PUBLIC void dissector_table_foreach (const char *name, DATFunc func,
149 WS_DLL_PUBLIC void dissector_all_tables_foreach_changed (DATFunc func,
151 WS_DLL_PUBLIC void dissector_table_foreach_handle(const char *name, DATFunc_handle func,
153 WS_DLL_PUBLIC void dissector_all_tables_foreach_table (DATFunc_table func,
154 gpointer user_data, GCompareFunc compare_key_func);
156 /* a protocol uses the function to register a sub-dissector table */
157 WS_DLL_PUBLIC dissector_table_t register_dissector_table(const char *name,
158 const char *ui_name, const ftenum_t type, const int base);
160 /* Find a dissector table by table name. */
161 WS_DLL_PUBLIC dissector_table_t find_dissector_table(const char *name);
163 /* Get the UI name for a sub-dissector table, given its internal name */
164 WS_DLL_PUBLIC const char *get_dissector_table_ui_name(const char *name);
166 /* Get the field type for values of the selector for a dissector table,
167 given the table's internal name */
168 WS_DLL_PUBLIC ftenum_t get_dissector_table_selector_type(const char *name);
170 /* Get the base to use when displaying values of the selector for a
171 sub-dissector table, given the table's internal name */
172 WS_DLL_PUBLIC int get_dissector_table_base(const char *name);
174 /* Add an entry to a uint dissector table. */
175 WS_DLL_PUBLIC void dissector_add_uint(const char *abbrev, const guint32 pattern,
176 dissector_handle_t handle);
178 /* Add an range of entries to a uint dissector table. */
179 WS_DLL_PUBLIC void dissector_add_uint_range(const char *abbrev, range_t *range,
180 dissector_handle_t handle);
182 /* Delete the entry for a dissector in a uint dissector table
183 with a particular pattern. */
184 WS_DLL_PUBLIC void dissector_delete_uint(const char *name, const guint32 pattern,
185 dissector_handle_t handle);
187 /* Delete an range of entries from a uint dissector table. */
188 WS_DLL_PUBLIC void dissector_delete_uint_range(const char *abbrev, range_t *range,
189 dissector_handle_t handle);
191 /* Delete all entries from a dissector table. */
192 WS_DLL_PUBLIC void dissector_delete_all(const char *name, dissector_handle_t handle);
194 /* Change the entry for a dissector in a uint dissector table
195 with a particular pattern to use a new dissector handle. */
196 WS_DLL_PUBLIC void dissector_change_uint(const char *abbrev, const guint32 pattern,
197 dissector_handle_t handle);
199 /* Reset an entry in a uint dissector table to its initial value. */
200 WS_DLL_PUBLIC void dissector_reset_uint(const char *name, const guint32 pattern);
202 /* Look for a given value in a given uint dissector table and, if found,
203 call the dissector with the arguments supplied, and return TRUE,
204 otherwise return FALSE. */
205 WS_DLL_PUBLIC gboolean dissector_try_uint(dissector_table_t sub_dissectors,
206 const guint32 uint_val, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
208 /* Look for a given value in a given uint dissector table and, if found,
209 call the dissector with the arguments supplied, and return TRUE,
210 otherwise return FALSE. */
211 gboolean dissector_try_uint_new(dissector_table_t sub_dissectors,
212 const guint32 uint_val, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, const gboolean add_proto_name, void *data);
214 /* Look for a given value in a given uint dissector table and, if found,
215 return the dissector handle for that value. */
216 WS_DLL_PUBLIC dissector_handle_t dissector_get_uint_handle(
217 dissector_table_t const sub_dissectors, const guint32 uint_val);
219 /* Add an entry to a string dissector table. */
220 WS_DLL_PUBLIC void dissector_add_string(const char *name, const gchar *pattern,
221 dissector_handle_t handle);
223 /* Delete the entry for a dissector in a string dissector table
224 with a particular pattern. */
225 WS_DLL_PUBLIC void dissector_delete_string(const char *name, const gchar *pattern,
226 dissector_handle_t handle);
228 /* Change the entry for a dissector in a string dissector table
229 with a particular pattern to use a new dissector handle. */
230 WS_DLL_PUBLIC void dissector_change_string(const char *name, const gchar *pattern,
231 dissector_handle_t handle);
233 /* Reset an entry in a string sub-dissector table to its initial value. */
234 WS_DLL_PUBLIC void dissector_reset_string(const char *name, const gchar *pattern);
236 /* Look for a given string in a given dissector table and, if found, call
237 the dissector with the arguments supplied, and return TRUE, otherwise
239 WS_DLL_PUBLIC gboolean dissector_try_string(dissector_table_t sub_dissectors,
240 const gchar *string, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
242 /* Look for a given value in a given string dissector table and, if found,
243 return the dissector handle for that value. */
244 WS_DLL_PUBLIC dissector_handle_t dissector_get_string_handle(
245 dissector_table_t sub_dissectors, const gchar *string);
247 /* Add a handle to the list of handles that *could* be used with this
248 table. That list is used by code in the UI. */
249 WS_DLL_PUBLIC void dissector_add_handle(const char *name, dissector_handle_t handle);
251 /* List of "heuristic" dissectors (which get handed a packet, look at it,
252 and either recognize it as being for their protocol, dissect it, and
253 return TRUE, or don't recognize it and return FALSE) to be called
254 by another dissector. */
255 typedef GSList *heur_dissector_list_t;
259 heur_dissector_t dissector;
260 protocol_t *protocol;
264 /** A protocol uses this function to register a heuristic sub-dissector list.
265 * Call this in the parent dissectors proto_register function.
267 * @param name the name of this protocol
268 * @param list the list of heuristic sub-dissectors to be registered
270 WS_DLL_PUBLIC void register_heur_dissector_list(const char *name,
271 heur_dissector_list_t *list);
273 WS_DLL_PUBLIC void dissector_all_heur_tables_foreach_table (DATFunc_heur_table func,
276 /** Try all the dissectors in a given heuristic dissector list. This is done,
277 * until we find one that recognizes the protocol.
278 * Call this while the parent dissector running.
280 * @param sub_dissectors the sub-dissector list
281 * @param tvb the tvbuff with the (remaining) packet data
282 * @param pinfo the packet info of this packet (additional info)
283 * @param tree the protocol tree to be build or NULL
284 * @param data parameter to pass to subdissector
285 * @return TRUE if the packet was recognized by the sub-dissector (stop dissection here)
287 WS_DLL_PUBLIC gboolean dissector_try_heuristic(heur_dissector_list_t sub_dissectors,
288 tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data);
290 /** Add a sub-dissector to a heuristic dissector list.
291 * Call this in the proto_handoff function of the sub-dissector.
293 * @param name the name of the "parent" protocol, e.g. "tcp"
294 * @param dissector the sub-dissector to be registered
295 * @param proto the protocol id of the sub-dissector
297 WS_DLL_PUBLIC void heur_dissector_add(const char *name, heur_dissector_t dissector,
300 /** Remove a sub-dissector from a heuristic dissector list.
301 * Call this in the prefs_reinit function of the sub-dissector.
303 * @param name the name of the "parent" protocol, e.g. "tcp"
304 * @param dissector the sub-dissector to be unregistered
305 * @param proto the protocol id of the sub-dissector
307 WS_DLL_PUBLIC void heur_dissector_delete(const char *name, heur_dissector_t dissector, const int proto);
309 /** Enable/Disable a sub-dissector in a heuristic dissector list
310 * Call this in the prefs_reinit function of the sub-dissector.
312 * @param name the name of the "parent" protocol, e.g. "tcp"
313 * @param dissector the sub-dissector to be disabled/enabled
314 * @param proto the protocol id of the sub-dissector
315 * @param enabled TRUE/FALSE to enable/disable the sub-dissector
317 extern void heur_dissector_set_enabled(const char *name, heur_dissector_t dissector, const int proto, const gboolean enabled);
319 /* Register a dissector. */
320 WS_DLL_PUBLIC dissector_handle_t register_dissector(const char *name, dissector_t dissector,
322 WS_DLL_PUBLIC dissector_handle_t new_register_dissector(const char *name, new_dissector_t dissector,
325 /* Get the long name of the protocol for a dissector handle. */
326 extern const char *dissector_handle_get_long_name(const dissector_handle_t handle);
328 /* Get the short name of the protocol for a dissector handle. */
329 WS_DLL_PUBLIC const char *dissector_handle_get_short_name(const dissector_handle_t handle);
331 /* Get the index of the protocol for a dissector handle. */
332 WS_DLL_PUBLIC int dissector_handle_get_protocol_index(const dissector_handle_t handle);
334 /* Find a dissector by name. */
335 WS_DLL_PUBLIC dissector_handle_t find_dissector(const char *name);
337 /* Get a dissector name from handle. */
338 WS_DLL_PUBLIC const char *dissector_handle_get_dissector_name(const dissector_handle_t handle);
340 /* Create an anonymous handle for a dissector. */
341 WS_DLL_PUBLIC dissector_handle_t create_dissector_handle(dissector_t dissector,
343 WS_DLL_PUBLIC dissector_handle_t new_create_dissector_handle(new_dissector_t dissector,
346 /* Call a dissector through a handle and if no dissector was found
347 * pass it over to the "data" dissector instead.
349 * @param handle The dissector to call.
350 * @param tvb The buffer to dissect.
351 * @param pinfo Packet Info.
352 * @param tree The protocol tree.
353 * @param data parameter to pass to dissector
354 * @return If the protocol for that handle isn't enabled call the data
355 * dissector. Otherwise, if the handle refers to a new-style
356 * dissector, call the dissector and return its return value, otherwise call
357 * it and return the length of the tvbuff pointed to by the argument.
359 WS_DLL_PUBLIC int call_dissector_with_data(dissector_handle_t handle, tvbuff_t *tvb,
360 packet_info *pinfo, proto_tree *tree, void *data);
361 WS_DLL_PUBLIC int call_dissector(dissector_handle_t handle, tvbuff_t *tvb,
362 packet_info *pinfo, proto_tree *tree);
364 /* Call a dissector through a handle but if no dissector was found
365 * just return 0 and do not call the "data" dissector instead.
367 * @param handle The dissector to call.
368 * @param tvb The buffer to dissect.
369 * @param pinfo Packet Info.
370 * @param tree The protocol tree.
371 * @param data parameter to pass to dissector
372 * @return If the protocol for that handle isn't enabled, return 0 without
373 * calling the dissector. Otherwise, if the handle refers to a new-style
374 * dissector, call the dissector and return its return value, otherwise call
375 * it and return the length of the tvbuff pointed to by the argument.
377 WS_DLL_PUBLIC int call_dissector_only(dissector_handle_t handle, tvbuff_t *tvb,
378 packet_info *pinfo, proto_tree *tree, void *data);
380 /* Do all one-time initialization. */
381 extern void dissect_init(void);
383 extern void dissect_cleanup(void);
386 * Given a tvbuff, and a length from a packet header, adjust the length
387 * of the tvbuff to reflect the specified length.
389 WS_DLL_PUBLIC void set_actual_length(tvbuff_t *tvb, const guint specified_len);
391 /* Allow protocols to register "init" routines, which are called before
392 we make a pass through a capture file and dissect all its packets
393 (e.g., when we read in a new capture file, or run a "filter packets"
394 or "colorize packets" pass over the current capture file). */
395 WS_DLL_PUBLIC void register_init_routine(void (*func)(void));
397 /* Initialize all data structures used for dissection. */
398 void init_dissection(void);
400 /* Free data structures allocated for dissection. */
401 void cleanup_dissection(void);
403 /* Allow protocols to register a "cleanup" routine to be
404 * run after the initial sequential run through the packets.
405 * Note that the file can still be open after this; this is not
406 * the final cleanup. */
407 WS_DLL_PUBLIC void register_postseq_cleanup_routine(void (*func)(void));
409 /* Call all the registered "postseq_cleanup" routines. */
410 WS_DLL_PUBLIC void postseq_cleanup_all_protocols(void);
412 /* Allow dissectors to register a "final_registration" routine
413 * that is run like the proto_register_XXX() routine, but the end
414 * end of the epan_init() function; that is, *after* all other
415 * subsystems, liked dfilters, have finished initializing. This is
416 * useful for dissector registration routines which need to compile
417 * display filters. dfilters can't initialize itself until all protocols
418 * have registereed themselvs. */
420 register_final_registration_routine(void (*func)(void));
422 /* Call all the registered "final_registration" routines. */
424 final_registration_all_protocols(void);
427 * Add a new data source to the list of data sources for a frame, given
428 * the tvbuff for the data source and its name.
430 WS_DLL_PUBLIC void add_new_data_source(packet_info *pinfo, tvbuff_t *tvb,
435 * Return the data source name, tvb.
438 WS_DLL_PUBLIC const char *get_data_source_name(const struct data_source *src);
439 WS_DLL_PUBLIC tvbuff_t *get_data_source_tvb(const struct data_source *src);
442 * Free up a frame's list of data sources.
444 extern void free_data_sources(packet_info *pinfo);
446 /* Mark another frame as depended upon by the current frame.
448 * This information is used to ensure that the dependend-upon frame is saved
449 * if the user does a File->Save-As of only the Displayed packets and the
450 * current frame passed the display filter.
452 WS_DLL_PUBLIC void mark_frame_as_depended_upon(packet_info *pinfo, guint32 frame_num);
455 * Dissectors should never modify the packet data.
457 extern void dissect_packet(epan_dissect_t *edt,
458 struct wtap_pkthdr *phdr, tvbuff_t *tvb,
459 frame_data *fd, column_info *cinfo);
461 /* These functions are in packet-ethertype.c */
462 extern void capture_ethertype(guint16 etype, const guchar *pd, int offset,
463 int len, packet_counts *ld);
464 WS_DLL_PUBLIC void ethertype(guint16 etype, tvbuff_t *tvb, int offset_after_ethertype,
465 packet_info *pinfo, proto_tree *tree, proto_tree *fh_tree,
466 int etype_id, int trailer_id, int fcs_len);
469 * Dump layer/selector/dissector records in a fashion similar to the
470 * proto_registrar_dump_* routines.
472 WS_DLL_PUBLIC void dissector_dump_decodes(void);
475 * For each heuristic dissector table, dump list of dissectors (filter_names) for that table
477 WS_DLL_PUBLIC void dissector_dump_heur_decodes(void);
480 * post dissectors are to be called by packet-frame.c after every other
481 * dissector has been called.
483 WS_DLL_PUBLIC void register_postdissector(dissector_handle_t);
484 extern gboolean have_postdissector(void);
485 extern void call_all_postdissectors(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
491 #endif /* __cplusplus */
493 #endif /* packet.h */