epan/dissectors/packet-text-media.c

   1 /* packet-text-media.c
   2  * Routines for text-based media dissection.
   3  *
   4  * NOTE - The media type is either found in pinfo->match_string,
   5  *        pinfo->private_data, or passed into the dissector (preferred)
   6  *
   7  * (C) Olivier Biot, 2004.
   8  *
   9  * $Id$
  10  *
  11  * Refer to the AUTHORS file or the AUTHORS section in the man page
  12  * for contacting the author(s) of this file.
  13  *
  14  * Wireshark - Network traffic analyzer
  15  * By Gerald Combs <gerald@wireshark.org>
  16  * Copyright 1998 Gerald Combs
  17  *
  18  * This program is free software; you can redistribute it and/or
  19  * modify it under the terms of the GNU General Public License
  20  * as published by the Free Software Foundation; either version 2
  21  * of the License, or (at your option) any later version.
  22  *
  23  * This program is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  * GNU General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU General Public License
  29  * along with this program; if not, write to the Free Software
  30  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  31  */
  32
  33 /* Edit this file with 4-space tabs */
  34
  35 #include "config.h"
  36
  37 #include <glib.h>
  38
  39 #include <epan/packet.h>
  40
  41
  42 /*
  43  * Media dissector for line-based text media like text/plain, message/http.
  44  *
  45  * TODO - character set and chunked transfer-coding
  46  */
  47
  48 /* Filterable header fields */
  49 static gint proto_text_lines = -1;
  50
  51 /* Subtrees */
  52 static gint ett_text_lines = -1;
  53
  54 /* Dissector handles */
  55 static dissector_handle_t xml_handle;
  56
  57 static int
  58 dissect_text_lines(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
  59 {
  60         proto_tree      *subtree;
  61         proto_item      *ti;
  62         gint            offset = 0, next_offset;
  63         gint            len;
  64         const char      *data_name;
  65         guint8          word[6];
  66         int length = tvb_length(tvb);
  67
  68         /* Check if this is actually xml
  69          * If there is less than 38 characters this is not XML
  70          * <?xml version="1.0" encoding="UTF-8"?>
  71          */
  72         if(length > 38){
  73                 tvb_get_nstringz0(tvb, 0, sizeof(word),word);
  74                 if (g_ascii_strncasecmp(word, "<?xml", 5) == 0){
  75                         call_dissector(xml_handle, tvb, pinfo, tree);
  76                         return tvb_length(tvb);
  77                 }
  78         }
  79
  80         data_name = pinfo->match_string;
  81         if (! (data_name && data_name[0])) {
  82                 /*
  83                  * No information from "match_string"
  84                  */
  85                 data_name = (char *)data;
  86                 if (! (data_name && data_name[0])) {
  87                         /*
  88                          * No information from dissector data
  89                          */
  90                         data_name = (char *)(pinfo->private_data);
  91                         if (! (data_name && data_name[0])) {
  92                                 /*
  93                                  * No information from "private_data"
  94                                  */
  95                                 data_name = NULL;
  96                         }
  97                 }
  98         }
  99
 100         if (data_name)
 101                 col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "(%s)",
 102                                 data_name);
 103
 104         if (tree) {
 105                 ti = proto_tree_add_item(tree, proto_text_lines,
 106                                 tvb, 0, -1, ENC_NA);
 107                 if (data_name)
 108                         proto_item_append_text(ti, ": %s", data_name);
 109                 subtree = proto_item_add_subtree(ti, ett_text_lines);
 110                 /* Read the media line by line */
 111                 while (tvb_reported_length_remaining(tvb, offset) != 0) {
 112                         /*
 113                          * XXX - we need to be passed the parameters
 114                          * of the content type via "pinfo->private_data",
 115                          * so that we know the character set.  We'd
 116                          * have to handle that character set, which
 117                          * might be a multibyte character set such
 118                          * as "iso-10646-ucs-2", or might require other
 119                          * special processing.
 120                          */
 121                         len = tvb_find_line_end(tvb, offset,
 122                                         tvb_ensure_length_remaining(tvb, offset),
 123                                         &next_offset, FALSE);
 124                         if (len == -1)
 125                                 break;
 126
 127                         /* We use next_offset - offset instead of len in the
 128                          * call to tvb_format_text() so it will include the
 129                          * line terminator(s) (\r and/or \n) in the display.
 130                          */
 131                         proto_tree_add_text(subtree, tvb, offset, next_offset - offset,
 132                                             "%s", tvb_format_text(tvb, offset,
 133                                                                   next_offset - offset));
 134                         offset = next_offset;
 135                 }
 136         }
 137
 138         return tvb_length(tvb);
 139 }
 140
 141 void
 142 proto_register_text_lines(void)
 143 {
 144         static gint *ett[] = {
 145                 &ett_text_lines,
 146         };
 147
 148         proto_register_subtree_array(ett, array_length(ett));
 149
 150         proto_text_lines = proto_register_protocol(
 151                         "Line-based text data", /* Long name */
 152                         "Line-based text data", /* Short name */
 153                         "data-text-lines");             /* Filter name */
 154         new_register_dissector("data-text-lines", dissect_text_lines, proto_text_lines);
 155 }
 156
 157 void
 158 proto_reg_handoff_text_lines(void)
 159 {
 160         dissector_handle_t text_lines_handle;
 161
 162         text_lines_handle = find_dissector("data-text-lines");
 163
 164         dissector_add_string("media_type", "text/plain", text_lines_handle); /* RFC 2046 */
 165         dissector_add_string("media_type", "text/richtext", text_lines_handle);  /* RFC 1341 */
 166         dissector_add_string("media_type", "text/enriched", text_lines_handle);  /* RFC 1896 */
 167         dissector_add_string("media_type", "text/parameters", text_lines_handle);
 168         /* W3C line-based textual media */
 169         dissector_add_string("media_type", "text/html", text_lines_handle);
 170         dissector_add_string("media_type", "text/xml-external-parsed-entity", text_lines_handle);
 171         dissector_add_string("media_type", "text/css", text_lines_handle);
 172         dissector_add_string("media_type", "application/xml-external-parsed-entity", text_lines_handle);
 173         dissector_add_string("media_type", "text/javascript", text_lines_handle);
 174         dissector_add_string("media_type", "application/x-javascript", text_lines_handle);
 175         dissector_add_string("media_type", "application/x-tia-p25-issi", text_lines_handle);
 176         dissector_add_string("media_type", "application/x-tia-p25-sndcp", text_lines_handle);
 177         dissector_add_string("media_type", "application/x-ns-proxy-autoconfig", text_lines_handle);
 178
 179         dissector_add_string("media_type", "text/vnd.sun.j2me.app-descriptor", text_lines_handle);
 180         dissector_add_string("media_type", "application/vnd.poc.refer-to", text_lines_handle);
 181         dissector_add_string("media_type", "application/vnd.drm.message", text_lines_handle);
 182
 183         dissector_add_string("media_type", "application/x-wms-logplaystats", text_lines_handle);
 184         dissector_add_string("media_type", "application/x-rtsp-udp-packetpair", text_lines_handle);
 185         xml_handle = find_dissector("xml");
 186 }