wireshark/epan/packet.h

239 lines
8.8 KiB
C
Raw Normal View History

/* packet.h
* Definitions for packet disassembly structures and routines
*
* $Id: packet.h,v 1.41 2001/11/26 05:41:13 hagbard Exp $
*
* 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.
*/
#ifndef __PACKET_H__
#define __PACKET_H__
#include "wiretap/wtap.h"
#include "proto.h"
#include "tvbuff.h"
#include "pint.h"
#include "to_str.h"
#include "value_string.h"
#include "column_info.h"
#include "frame_data.h"
#include "packet_info.h"
#include "column-utils.h"
#include "epan.h"
#define hi_nibble(b) (((b) & 0xf0) >> 4)
#define lo_nibble(b) ((b) & 0x0f)
/* Useful when you have an array whose size you can tell at compile-time */
#define array_length(x) (sizeof x / sizeof x[0])
/* Check whether the "len" bytes of data starting at "offset" is
* entirely inside the captured data for this packet. */
#define BYTES_ARE_IN_FRAME(offset, captured_len, len) \
((offset) + (len) <= (captured_len))
/* To pass one of two strings, singular or plural */
#define plurality(d,s,p) ((d) == 1 ? (s) : (p))
typedef struct _packet_counts {
gint sctp;
gint tcp;
gint udp;
gint icmp;
gint ospf;
gint gre;
gint netbios;
gint ipx;
gint vines;
gint other;
gint total;
} packet_counts;
/* Types of character encodings */
typedef enum {
CHAR_ASCII = 0, /* ASCII */
CHAR_EBCDIC = 1 /* EBCDIC */
} char_enc;
/* Struct for boolean enumerations */
typedef struct true_false_string {
char *true_string;
char *false_string;
} true_false_string;
extern void packet_init(void);
extern void packet_cleanup(void);
/* Hash table for matching port numbers and dissectors */
typedef GHashTable* dissector_table_t;
/* types for sub-dissector lookup */
Allow either old-style (pre-tvbuff) or new-style (tvbuffified) dissectors to be registered as dissectors for particular ports, registered as heuristic dissectors, and registered as dissectors for conversations, and have routines to be used both by old-style and new-style dissectors to call registered dissectors. Have the code that calls those dissectors translate the arguments as necessary. (For conversation dissectors, replace "find_conversation_dissector()", which just returns a pointer to the dissector, with "old_try_conversation_dissector()" and "try_conversation_dissector()", which actually call the dissector, so that there's a single place at which we can do that translation. Also make "dissector_lookup()" static and, instead of calling it and, if it returns a non-null pointer, calling that dissector, just use "old_dissector_try_port()" or "dissector_try_port()", for the same reason.) This allows some dissectors that took old-style arguments and immediately translated them to new-style arguments to just take new-style arguments; make them do so. It also allows some new-style dissectors not to have to translate arguments before calling routines to look up and call dissectors; make them not do so. Get rid of checks for too-short frames in new-style dissectors - the tvbuff code does those checks for you. Give the routines to register old-style dissectors, and to call dissectors from old-style dissectors, names beginning with "old_", with the routines for new-style dissectors not having the "old_". Update the dissectors that use those routines appropriately. Rename "dissect_data()" to "old_dissect_data()", and "dissect_data_tvb()" to "dissect_data()". svn path=/trunk/; revision=2218
2000-08-07 03:21:25 +00:00
typedef void (*old_dissector_t)(const u_char *, int, frame_data *, proto_tree *);
typedef void (*dissector_t)(tvbuff_t *, packet_info *, proto_tree *);
typedef void (*DATFunc) (gchar *table_name, gpointer key, gpointer value, gpointer user_data);
/* Opaque structure - provides type checking but no access to components */
typedef struct dtbl_entry dtbl_entry_t;
extern gint dissector_get_proto (dtbl_entry_t * entry);
extern gint dissector_get_initial_proto (dtbl_entry_t * entry);
extern void dissector_table_foreach_changed (char *name, DATFunc func,
gpointer user_data);
extern void dissector_table_foreach (char *name, DATFunc func,
gpointer user_data);
extern void dissector_all_tables_foreach_changed (DATFunc func,
gpointer user_data);
/* a protocol uses the function to register a sub-dissector table */
extern dissector_table_t register_dissector_table(const char *name);
/* Add a sub-dissector to a dissector table. Called by the protocol routine */
/* that wants to register a sub-dissector. */
extern void dissector_add(const char *abbrev, guint32 pattern,
dissector_t dissector, int proto);
/* Add a sub-dissector to a dissector table. Called by the protocol routine */
/* that wants to de-register a sub-dissector. */
extern void dissector_delete(const char *name, guint32 pattern,
dissector_t dissector);
extern void dissector_change(const char *abbrev, guint32 pattern,
dissector_t dissector, int proto);
/* Reset a dissector in a sub-dissector table to its initial value. */
extern void dissector_reset(const char *name, guint32 pattern);
/* Look for a given port in a given dissector table and, if found, call
the dissector with the arguments supplied, and return TRUE, otherwise
return FALSE. */
extern gboolean dissector_try_port(dissector_table_t sub_dissectors,
guint32 port, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
/* List of "heuristic" dissectors (which get handed a packet, look at it,
and either recognize it as being for their protocol, dissect it, and
return TRUE, or don't recognize it and return FALSE) to be called
by another dissector. */
typedef GSList *heur_dissector_list_t;
/* Type of a heuristic dissector */
Allow either old-style (pre-tvbuff) or new-style (tvbuffified) dissectors to be registered as dissectors for particular ports, registered as heuristic dissectors, and registered as dissectors for conversations, and have routines to be used both by old-style and new-style dissectors to call registered dissectors. Have the code that calls those dissectors translate the arguments as necessary. (For conversation dissectors, replace "find_conversation_dissector()", which just returns a pointer to the dissector, with "old_try_conversation_dissector()" and "try_conversation_dissector()", which actually call the dissector, so that there's a single place at which we can do that translation. Also make "dissector_lookup()" static and, instead of calling it and, if it returns a non-null pointer, calling that dissector, just use "old_dissector_try_port()" or "dissector_try_port()", for the same reason.) This allows some dissectors that took old-style arguments and immediately translated them to new-style arguments to just take new-style arguments; make them do so. It also allows some new-style dissectors not to have to translate arguments before calling routines to look up and call dissectors; make them not do so. Get rid of checks for too-short frames in new-style dissectors - the tvbuff code does those checks for you. Give the routines to register old-style dissectors, and to call dissectors from old-style dissectors, names beginning with "old_", with the routines for new-style dissectors not having the "old_". Update the dissectors that use those routines appropriately. Rename "dissect_data()" to "old_dissect_data()", and "dissect_data_tvb()" to "dissect_data()". svn path=/trunk/; revision=2218
2000-08-07 03:21:25 +00:00
typedef gboolean (*heur_dissector_t)(tvbuff_t *, packet_info *,
proto_tree *);
/* A protocol uses this function to register a heuristic dissector list */
extern void register_heur_dissector_list(const char *name,
heur_dissector_list_t *list);
/* Add a sub-dissector to a heuristic dissector list. Called by the
protocol routine that wants to register a sub-dissector. */
extern void heur_dissector_add(const char *name, heur_dissector_t dissector,
int proto);
/* Try all the dissectors in a given heuristic dissector list until
we find one that recognizes the protocol, in which case we return
TRUE, or we run out of dissectors, in which case we return FALSE. */
extern gboolean dissector_try_heuristic(heur_dissector_list_t sub_dissectors,
Allow either old-style (pre-tvbuff) or new-style (tvbuffified) dissectors to be registered as dissectors for particular ports, registered as heuristic dissectors, and registered as dissectors for conversations, and have routines to be used both by old-style and new-style dissectors to call registered dissectors. Have the code that calls those dissectors translate the arguments as necessary. (For conversation dissectors, replace "find_conversation_dissector()", which just returns a pointer to the dissector, with "old_try_conversation_dissector()" and "try_conversation_dissector()", which actually call the dissector, so that there's a single place at which we can do that translation. Also make "dissector_lookup()" static and, instead of calling it and, if it returns a non-null pointer, calling that dissector, just use "old_dissector_try_port()" or "dissector_try_port()", for the same reason.) This allows some dissectors that took old-style arguments and immediately translated them to new-style arguments to just take new-style arguments; make them do so. It also allows some new-style dissectors not to have to translate arguments before calling routines to look up and call dissectors; make them not do so. Get rid of checks for too-short frames in new-style dissectors - the tvbuff code does those checks for you. Give the routines to register old-style dissectors, and to call dissectors from old-style dissectors, names beginning with "old_", with the routines for new-style dissectors not having the "old_". Update the dissectors that use those routines appropriately. Rename "dissect_data()" to "old_dissect_data()", and "dissect_data_tvb()" to "dissect_data()". svn path=/trunk/; revision=2218
2000-08-07 03:21:25 +00:00
tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
/* List of "conversation" dissectors (they're not heuristic, but are
assigned to a conversation if some other dissector sees some traffic
saying "traffic between these hosts on these ports will be of type
XXX", e.g. RTSP traffic doing so).
These lists are for use by the UI, which, for a given conversation,
would offer a list of dissectors that could be used with it; this
would include dissectors on the conversation dissector list for
the transport-layer protocol for the conversation, as well as
dissectors for any port-based lists for that protocol (as a conversation
between two ports, both of which have dissectors associated with them,
might have been given to the wrong one of those dissectors). */
typedef GSList *conv_dissector_list_t;
/* A protocol uses this function to register a conversation dissector list */
extern void register_conv_dissector_list(const char *name,
conv_dissector_list_t *list);
/* Add a sub-dissector to a conversation dissector list. Called by the
protocol routine that wants to register a sub-dissector. */
extern void conv_dissector_add(const char *name, dissector_t dissector,
int proto);
/* Opaque structure - provides type checking but no access to components */
typedef struct conv_dtbl_entry conv_dtbl_entry_t;
extern gint conv_dissector_get_proto (conv_dtbl_entry_t * entry);
extern void dissector_conv_foreach(char *name, DATFunc func,
gpointer user_data);
extern void dissector_all_conv_foreach(DATFunc func, gpointer user_data);
/* Handle for dissectors you call directly.
This handle is opaque outside of "packet.c". */
struct dissector_handle;
Add a mechanism by which a dissector can be registered by name, another dissector can get a "handle" for that dissector by name and then call that dissector through the handle. This allows dissectors that can't be called through a port table or a heuristic table to be called from other dissectors without directly referring to the dissector function - dynamically-loaded modules, under Windows, cannot directly call functions in the main program, and non-plugin dissectors are in the main program and thus cannot be called from plugin dissectors unless either 1) a pointer to the dissector is put in the Big Transfer Vector or 2) some other mechanism for getting a pointer to the dissector is provided. This mechanism could also support registering old-style dissectors and calling them from new-style dissectors without the new-style dissector having to do the argument translation itself (I didn't add support for registering old-style dissectors because I'd prefer to have people tvbuffify their code if they have to register a dissector...). It could also, in the future, perhaps support disabling of protocols; setting "pinfo->current_proto"; inside "call_dissector()" - and inside "{old_}dissector_try_port()" and "{old_"dissector_try_heuristic()" - allowing a pile of stuff that currently has to be done in every dissector be done by common code. (I have some ideas about how to do this, by having "proto_register_protocol()" take an abbreviation - of the sort that would be put in, for example, "pinfo->current_proto" - as an argument; having the calls to register dissectors take an index returned by "proto_register_protocol()" as an argument. The abbreviation could be used elsewhere as well, e.g. in the "Decoding" tab of the "Edit->Protocols" dialog box, and in a GUI for constructing protocol filters. Watch this space.) Make "dissect_sdp()" the first client of this mechanism; it's now static to "packet-sdp.c", and all dissectors that call it - including the MGCP plugin - now call it through a dissector handle fetched by "find_dissector()". (Next step - see if Ethereal can now compile on Windows as a result of this.) svn path=/trunk/; revision=2647
2000-11-15 07:07:52 +00:00
typedef struct dissector_handle *dissector_handle_t;
/* Register a dissector. */
extern void register_dissector(const char *name, dissector_t dissector,
int proto);
Add a mechanism by which a dissector can be registered by name, another dissector can get a "handle" for that dissector by name and then call that dissector through the handle. This allows dissectors that can't be called through a port table or a heuristic table to be called from other dissectors without directly referring to the dissector function - dynamically-loaded modules, under Windows, cannot directly call functions in the main program, and non-plugin dissectors are in the main program and thus cannot be called from plugin dissectors unless either 1) a pointer to the dissector is put in the Big Transfer Vector or 2) some other mechanism for getting a pointer to the dissector is provided. This mechanism could also support registering old-style dissectors and calling them from new-style dissectors without the new-style dissector having to do the argument translation itself (I didn't add support for registering old-style dissectors because I'd prefer to have people tvbuffify their code if they have to register a dissector...). It could also, in the future, perhaps support disabling of protocols; setting "pinfo->current_proto"; inside "call_dissector()" - and inside "{old_}dissector_try_port()" and "{old_"dissector_try_heuristic()" - allowing a pile of stuff that currently has to be done in every dissector be done by common code. (I have some ideas about how to do this, by having "proto_register_protocol()" take an abbreviation - of the sort that would be put in, for example, "pinfo->current_proto" - as an argument; having the calls to register dissectors take an index returned by "proto_register_protocol()" as an argument. The abbreviation could be used elsewhere as well, e.g. in the "Decoding" tab of the "Edit->Protocols" dialog box, and in a GUI for constructing protocol filters. Watch this space.) Make "dissect_sdp()" the first client of this mechanism; it's now static to "packet-sdp.c", and all dissectors that call it - including the MGCP plugin - now call it through a dissector handle fetched by "find_dissector()". (Next step - see if Ethereal can now compile on Windows as a result of this.) svn path=/trunk/; revision=2647
2000-11-15 07:07:52 +00:00
/* Find a dissector by name. */
extern dissector_handle_t find_dissector(const char *name);
Add a mechanism by which a dissector can be registered by name, another dissector can get a "handle" for that dissector by name and then call that dissector through the handle. This allows dissectors that can't be called through a port table or a heuristic table to be called from other dissectors without directly referring to the dissector function - dynamically-loaded modules, under Windows, cannot directly call functions in the main program, and non-plugin dissectors are in the main program and thus cannot be called from plugin dissectors unless either 1) a pointer to the dissector is put in the Big Transfer Vector or 2) some other mechanism for getting a pointer to the dissector is provided. This mechanism could also support registering old-style dissectors and calling them from new-style dissectors without the new-style dissector having to do the argument translation itself (I didn't add support for registering old-style dissectors because I'd prefer to have people tvbuffify their code if they have to register a dissector...). It could also, in the future, perhaps support disabling of protocols; setting "pinfo->current_proto"; inside "call_dissector()" - and inside "{old_}dissector_try_port()" and "{old_"dissector_try_heuristic()" - allowing a pile of stuff that currently has to be done in every dissector be done by common code. (I have some ideas about how to do this, by having "proto_register_protocol()" take an abbreviation - of the sort that would be put in, for example, "pinfo->current_proto" - as an argument; having the calls to register dissectors take an index returned by "proto_register_protocol()" as an argument. The abbreviation could be used elsewhere as well, e.g. in the "Decoding" tab of the "Edit->Protocols" dialog box, and in a GUI for constructing protocol filters. Watch this space.) Make "dissect_sdp()" the first client of this mechanism; it's now static to "packet-sdp.c", and all dissectors that call it - including the MGCP plugin - now call it through a dissector handle fetched by "find_dissector()". (Next step - see if Ethereal can now compile on Windows as a result of this.) svn path=/trunk/; revision=2647
2000-11-15 07:07:52 +00:00
/* Call a dissector through a handle. */
extern void call_dissector(dissector_handle_t handle, tvbuff_t *tvb,
Add a mechanism by which a dissector can be registered by name, another dissector can get a "handle" for that dissector by name and then call that dissector through the handle. This allows dissectors that can't be called through a port table or a heuristic table to be called from other dissectors without directly referring to the dissector function - dynamically-loaded modules, under Windows, cannot directly call functions in the main program, and non-plugin dissectors are in the main program and thus cannot be called from plugin dissectors unless either 1) a pointer to the dissector is put in the Big Transfer Vector or 2) some other mechanism for getting a pointer to the dissector is provided. This mechanism could also support registering old-style dissectors and calling them from new-style dissectors without the new-style dissector having to do the argument translation itself (I didn't add support for registering old-style dissectors because I'd prefer to have people tvbuffify their code if they have to register a dissector...). It could also, in the future, perhaps support disabling of protocols; setting "pinfo->current_proto"; inside "call_dissector()" - and inside "{old_}dissector_try_port()" and "{old_"dissector_try_heuristic()" - allowing a pile of stuff that currently has to be done in every dissector be done by common code. (I have some ideas about how to do this, by having "proto_register_protocol()" take an abbreviation - of the sort that would be put in, for example, "pinfo->current_proto" - as an argument; having the calls to register dissectors take an index returned by "proto_register_protocol()" as an argument. The abbreviation could be used elsewhere as well, e.g. in the "Decoding" tab of the "Edit->Protocols" dialog box, and in a GUI for constructing protocol filters. Watch this space.) Make "dissect_sdp()" the first client of this mechanism; it's now static to "packet-sdp.c", and all dissectors that call it - including the MGCP plugin - now call it through a dissector handle fetched by "find_dissector()". (Next step - see if Ethereal can now compile on Windows as a result of this.) svn path=/trunk/; revision=2647
2000-11-15 07:07:52 +00:00
packet_info *pinfo, proto_tree *tree);
/* Do all one-time initialization. */
extern void dissect_init(void);
extern void dissect_cleanup(void);
/*
* Given a tvbuff, a packet_info *, and a length from a packet header,
* adjust the length of the tvbuff, and the "len" and "captured_len"
* members of the "packet_info" structure, to reflect the specified
* length.
*/
extern void set_actual_length(tvbuff_t *tvb, packet_info *pinfo,
guint 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). */
extern void register_init_routine(void (*func)(void));
/* Call all the registered "init" routines. */
extern void init_all_protocols(void);
/*
* Dissectors should never modify the packet data.
*/
extern void dissect_packet(struct _epan_dissect_t *edt,
union wtap_pseudo_header *pseudo_header, const u_char *pd,
frame_data *fd);
/* These functions are in packet-ethertype.c */
extern void capture_ethertype(guint16 etype, const u_char *pd, int offset,
int len, packet_counts *ld);
extern void ethertype(guint16 etype, tvbuff_t *tvb, int offset_after_ethertype,
packet_info *pinfo, proto_tree *tree, proto_tree *fh_tree,
int etype_id, int trailer_id);
#endif /* packet.h */