epan/capture_dissectors.c

   1 /* capture_dissectors.c
   2  * Routines for handling capture dissectors
   3  *
   4  * Wireshark - Network traffic analyzer
   5  * By Gerald Combs <gerald@wireshark.org>
   6  * Copyright 1998 Gerald Combs
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; either version 2
  11  * of the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22
  23 #include "config.h"
  24
  25 #include <glib.h>
  26 #include "packet.h"
  27
  28 #include "capture_dissectors.h"
  29
  30 struct capture_dissector_table {
  31     GHashTable *hash_table;
  32     const char *ui_name;
  33 };
  34
  35 struct capture_dissector_handle
  36 {
  37     guint32 pattern;
  38     capture_dissector_t dissector;
  39     protocol_t* protocol;
  40 };
  41
  42 typedef struct capture_dissector_count
  43 {
  44     guint32 count;
  45 } capture_dissector_count_t;
  46
  47 static GHashTable *capture_dissector_tables = NULL;
  48
  49 static void
  50 destroy_capture_dissector_table(void *data)
  51 {
  52     struct capture_dissector_table *table = (struct capture_dissector_table *)data;
  53
  54     g_hash_table_destroy(table->hash_table);
  55     g_free(data);
  56 }
  57
  58 void capture_dissector_init(void)
  59 {
  60     capture_dissector_tables = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, destroy_capture_dissector_table);
  61 }
  62
  63 void capture_dissector_cleanup(void)
  64 {
  65     g_hash_table_destroy(capture_dissector_tables);
  66 }
  67
  68 void register_capture_dissector_table(const char *name, const char *ui_name)
  69 {
  70     struct capture_dissector_table*     sub_dissectors;
  71
  72     /* Make sure the registration is unique */
  73     if(g_hash_table_lookup( capture_dissector_tables, name )) {
  74         g_error("The capture dissector table %s (%s) is already registered - are you using a buggy plugin?", name, ui_name);
  75     }
  76
  77     sub_dissectors = g_new(struct capture_dissector_table, 1);
  78
  79     sub_dissectors->hash_table = g_hash_table_new_full( g_direct_hash, g_direct_equal, NULL, NULL );
  80     sub_dissectors->ui_name = ui_name;
  81     g_hash_table_insert( capture_dissector_tables, (gpointer)name, (gpointer) sub_dissectors );
  82
  83 }
  84
  85 void register_capture_dissector(const char* name, const guint32 pattern, capture_dissector_t dissector, const int proto)
  86 {
  87     struct capture_dissector_table*     sub_dissectors;
  88     struct capture_dissector_handle *handle;
  89
  90     /* Make sure table exists */
  91     sub_dissectors = (struct capture_dissector_table*)g_hash_table_lookup( capture_dissector_tables, name );
  92     g_assert(sub_dissectors != NULL);
  93
  94     /* Make sure the registration is unique */
  95     g_assert(g_hash_table_lookup(sub_dissectors->hash_table, GUINT_TO_POINTER(pattern)) == NULL);
  96
  97     handle                = wmem_new(wmem_epan_scope(), struct capture_dissector_handle);
  98     handle->pattern       = pattern;
  99     handle->dissector     = dissector;
 100     handle->protocol      = find_protocol_by_id(proto);
 101
 102     g_hash_table_insert(sub_dissectors->hash_table, GUINT_TO_POINTER(pattern), (gpointer) handle);
 103 }
 104
 105 gboolean try_capture_dissector(const char* name, const guint32 pattern, const guchar *pd, int offset, int len, capture_packet_info_t *cpinfo, const union wtap_pseudo_header *pseudo_header)
 106 {
 107     struct capture_dissector_table*     sub_dissectors;
 108     struct capture_dissector_handle* handle;
 109
 110     sub_dissectors = (struct capture_dissector_table*)g_hash_table_lookup( capture_dissector_tables, name );
 111     if (sub_dissectors == NULL)
 112     {
 113         /* XXX - ASSERT? */
 114         return FALSE;
 115     }
 116
 117     handle = (struct capture_dissector_handle *)g_hash_table_lookup(sub_dissectors->hash_table, GUINT_TO_POINTER(pattern));
 118     if (handle == NULL)
 119         return FALSE;
 120
 121     return handle->dissector(pd, offset, len, cpinfo, pseudo_header);
 122 }
 123
 124 guint32 capture_dissector_get_count(packet_counts* counts, const int proto)
 125 {
 126     capture_dissector_count_t* hash_count = (capture_dissector_count_t*)g_hash_table_lookup(counts->counts_hash, GUINT_TO_POINTER(proto));
 127     if (hash_count == NULL)
 128         return 0;
 129
 130     return hash_count->count;
 131 }
 132
 133 void capture_dissector_increment_count(capture_packet_info_t *cpinfo, const int proto)
 134 {
 135     /* See if we already have a counter for the protocol */
 136     capture_dissector_count_t* hash_count = (capture_dissector_count_t*)g_hash_table_lookup(cpinfo->counts, GUINT_TO_POINTER(proto));
 137     if (hash_count == NULL)
 138     {
 139         hash_count = g_new0(capture_dissector_count_t, 1);
 140         g_hash_table_insert(cpinfo->counts, GUINT_TO_POINTER(proto), (gpointer)hash_count);
 141     }
 142
 143     hash_count->count++;
 144 }
 145
 146 /*
 147  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 148  *
 149  * Local variables:
 150  * c-basic-offset: 4
 151  * tab-width: 8
 152  * indent-tabs-mode: nil
 153  * End:
 154  *
 155  * vi: set shiftwidth=4 tabstop=8 expandtab:
 156  * :indentSize=4:tabSize=8:noTabs=true:
 157  */