epan/dissectors/packet-data.c

   1 /* packet-data.c
   2  * Routines for raw data (default case)
   3  * Gilbert Ramirez <gram@alumni.rice.edu>
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  24  */
  25
  26 #define NEW_PROTO_TREE_API
  27
  28 #include "config.h"
  29
  30 #include <glib.h>
  31
  32 #include <wsutil/md5.h>
  33
  34 #include <epan/packet.h>
  35 #include <epan/prefs.h>
  36 #include "packet-data.h"
  37
  38 /* proto_data cannot be static because it's referenced in the
  39  * print routines
  40  */
  41 void proto_register_data(void);
  42
  43 int proto_data = -1;
  44
  45 #define DATA_HFI_INIT HFI_INIT(proto_data)
  46
  47 static header_field_info hfi_data_data DATA_HFI_INIT =
  48           { "Data", "data.data", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL };
  49
  50 static header_field_info hfi_data_text DATA_HFI_INIT =
  51           { "Text", "data.text", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL };
  52
  53 static header_field_info hfi_data_len DATA_HFI_INIT =
  54           { "Length", "data.len", FT_INT32, BASE_DEC, NULL, 0x0, NULL, HFILL };
  55
  56 static header_field_info hfi_data_md5_hash DATA_HFI_INIT =
  57           { "Payload MD5 hash", "data.md5_hash", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL };
  58
  59 static gboolean new_pane = FALSE;
  60 static gboolean show_as_text = FALSE;
  61 static gboolean generate_md5_hash = FALSE;
  62
  63 static gint ett_data = -1;
  64
  65 static void
  66 dissect_data(tvbuff_t *tvb, packet_info *pinfo _U_ , proto_tree *tree)
  67 {
  68         gint bytes;
  69
  70         if (tree) {
  71                 bytes = tvb_length_remaining(tvb, 0);
  72                 if (bytes > 0) {
  73                         tvbuff_t   *data_tvb;
  74                         proto_item *ti;
  75                         proto_tree *data_tree;
  76                         if (new_pane) {
  77                                 guint8 *real_data = (guint8 *)tvb_memdup(NULL, tvb, 0, bytes);
  78                                 data_tvb = tvb_new_child_real_data(tvb,real_data,bytes,bytes);
  79                                 tvb_set_free_cb(data_tvb, g_free);
  80                                 add_new_data_source(pinfo, data_tvb, "Not dissected data bytes");
  81                         } else {
  82                                 data_tvb = tvb;
  83                         }
  84                         ti = proto_tree_add_protocol_format(tree, proto_data, tvb,
  85                                 0,
  86                                 bytes, "Data (%d byte%s)", bytes,
  87                                 plurality(bytes, "", "s"));
  88                         data_tree = proto_item_add_subtree(ti, ett_data);
  89
  90                         proto_tree_add_item(data_tree, &hfi_data_data, data_tvb, 0, bytes, ENC_NA);
  91
  92                         if (show_as_text) {
  93                                 proto_tree_add_item(data_tree, &hfi_data_text, data_tvb, 0, bytes, ENC_ASCII|ENC_NA);
  94                         }
  95
  96                         if(generate_md5_hash) {
  97                                 const guint8 *cp;
  98                                 md5_state_t   md_ctx;
  99                                 md5_byte_t    digest[16];
 100                                 const gchar  *digest_string;
 101
 102                                 cp = tvb_get_ptr(tvb, 0, bytes);
 103
 104                                 md5_init(&md_ctx);
 105                                 md5_append(&md_ctx, cp, bytes);
 106                                 md5_finish(&md_ctx, digest);
 107
 108                                 digest_string = bytestring_to_str(digest, 16, '\0');
 109                                 ti = proto_tree_add_string(data_tree, &hfi_data_md5_hash, tvb, 0, 0, digest_string);
 110                                 PROTO_ITEM_SET_GENERATED(ti);
 111                         }
 112
 113                         ti = proto_tree_add_int(data_tree, &hfi_data_len, data_tvb, 0, 0, bytes);
 114                         PROTO_ITEM_SET_GENERATED (ti);
 115                 }
 116         }
 117 }
 118
 119 void
 120 proto_register_data(void)
 121 {
 122 #ifndef HAVE_HFI_SECTION_INIT
 123         static header_field_info *hfi[] = {
 124                 &hfi_data_data,
 125                 &hfi_data_text,
 126                 &hfi_data_md5_hash,
 127                 &hfi_data_len,
 128         };
 129 #endif
 130
 131         static gint *ett[] = {
 132                 &ett_data
 133         };
 134
 135         module_t *module_data;
 136
 137         proto_data = proto_register_protocol (
 138                 "Data",         /* name */
 139                 "Data",         /* short name */
 140                 "data"          /* abbrev */
 141                 );
 142
 143         register_dissector("data", dissect_data, proto_data);
 144
 145         proto_register_fields(proto_data, hfi, array_length(hfi));
 146         proto_register_subtree_array(ett, array_length(ett));
 147
 148         module_data = prefs_register_protocol( proto_data, NULL);
 149         prefs_register_bool_preference(module_data,
 150                 "datapref.newpane",
 151                 "Show not dissected data on new Packet Bytes pane",
 152                 "Show not dissected data on new Packet Bytes pane",
 153                 &new_pane);
 154         prefs_register_bool_preference(module_data,
 155                 "show_as_text",
 156                 "Show data as text",
 157                 "Show data as text in the Packet Details pane",
 158                 &show_as_text);
 159         prefs_register_bool_preference(module_data,
 160                                        "md5_hash",
 161                                        "Generate MD5 hash",
 162                                        "Whether or not MD5 hashes should be generated and shown for each payload.",
 163                                        &generate_md5_hash);
 164
 165         /*
 166          * "Data" is used to dissect something whose normal dissector
 167          * is disabled, so it cannot itself be disabled.
 168          */
 169         proto_set_cant_toggle(proto_data);
 170 }