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  *        or passed into the dissector
   6  *
   7  * (C) Olivier Biot, 2004.
   8  *
   9  * Refer to the AUTHORS file or the AUTHORS section in the man page
  10  * for contacting the author(s) of this file.
  11  *
  12  * Wireshark - Network traffic analyzer
  13  * By Gerald Combs <gerald@wireshark.org>
  14  * Copyright 1998 Gerald Combs
  15  *
  16  * SPDX-License-Identifier: GPL-2.0-or-later
  17  */
  18
  19 /* Edit this file with 4-space tabs */
  20
  21 #include "config.h"
  22
  23 #include <epan/packet.h>
  24
  25 #include "packet-media-type.h"
  26
  27 /*
  28  * Media dissector for line-based text media like text/plain, message/http.
  29  *
  30  * TODO - character set and chunked transfer-coding
  31  */
  32 void proto_register_text_lines(void);
  33 void proto_reg_handoff_text_lines(void);
  34
  35 /* Filterable header fields */
  36 static int proto_text_lines;
  37
  38 /* Subtrees */
  39 static int ett_text_lines;
  40
  41 /* Dissector handles */
  42 static dissector_handle_t xml_handle;
  43
  44 static int
  45 dissect_text_lines(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data)
  46 {
  47         proto_tree      *subtree;
  48         proto_item      *ti;
  49         int             offset = 0, next_offset;
  50         int             len;
  51         media_content_info_t *content_info;
  52         const char      *data_name;
  53         int length = tvb_captured_length(tvb);
  54
  55         /* Check if this is actually xml
  56          * If there is less than 38 characters this is not XML
  57          * <?xml version="1.0" encoding="UTF-8"?>
  58          */
  59         if(length > 38){
  60                 if (tvb_strncaseeql(tvb, 0, "<?xml", 5) == 0){
  61                         call_dissector(xml_handle, tvb, pinfo, tree);
  62                         return length;
  63                 }
  64         }
  65
  66         data_name = pinfo->match_string;
  67         if (! (data_name && data_name[0])) {
  68                 /*
  69                  * No information from "match_string"
  70                  */
  71                 content_info = (media_content_info_t *)data;
  72                 if (content_info == NULL) {
  73                         /*
  74                          * No information from dissector data
  75                          */
  76                         data_name = NULL;
  77                 } else {
  78                         data_name = content_info->media_str;
  79                         if (! (data_name && data_name[0])) {
  80                                 /*
  81                                  * No information from dissector data
  82                                  */
  83                                 data_name = NULL;
  84                         }
  85                 }
  86         }
  87
  88         if (data_name)
  89                 col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "(%s)",
  90                                 data_name);
  91
  92         if (tree) {
  93                 unsigned lines_read = 0;
  94                 ti = proto_tree_add_item(tree, proto_text_lines,
  95                                 tvb, 0, -1, ENC_NA);
  96                 if (data_name)
  97                         proto_item_append_text(ti, ": %s", data_name);
  98                 subtree = proto_item_add_subtree(ti, ett_text_lines);
  99                 /* Read the media line by line */
 100                 while (tvb_offset_exists(tvb, offset)) {
 101                         /*
 102                          * XXX - we need to be passed the parameters
 103                          * of the content type via data parameter,
 104                          * so that we know the character set.  We'd
 105                          * have to handle that character set, which
 106                          * might be a multibyte character set such
 107                          * as "iso-10646-ucs-2", or might require other
 108                          * special processing.
 109                          */
 110                         len = tvb_find_line_end(tvb, offset, -1, &next_offset, false);
 111                         if (len == -1)
 112                                 break;
 113
 114                         /* We use next_offset - offset instead of len in the
 115                          * call to proto_tree_add_format_text() so it will include the
 116                          * line terminator(s) (\r and/or \n) in the display.
 117                          */
 118                         proto_tree_add_format_text(subtree, tvb, offset, next_offset - offset);
 119                         lines_read++;
 120                         offset = next_offset;
 121                 }
 122                 proto_item_append_text(subtree, " (%u lines)", lines_read);
 123         }
 124
 125         return length;
 126 }
 127
 128 void
 129 proto_register_text_lines(void)
 130 {
 131         static int *ett[] = {
 132                 &ett_text_lines,
 133         };
 134
 135         proto_register_subtree_array(ett, array_length(ett));
 136
 137         proto_text_lines = proto_register_protocol("Line-based text data", "Line-based text data", "data-text-lines");
 138         register_dissector("data-text-lines", dissect_text_lines, proto_text_lines);
 139 }
 140
 141 void
 142 proto_reg_handoff_text_lines(void)
 143 {
 144         dissector_handle_t text_lines_handle;
 145
 146         text_lines_handle = find_dissector("data-text-lines");
 147
 148         dissector_add_string("media_type", "text/plain", text_lines_handle); /* RFC 2046 */
 149         dissector_add_string("media_type", "text/richtext", text_lines_handle);  /* RFC 1341 */
 150         dissector_add_string("media_type", "text/enriched", text_lines_handle);  /* RFC 1896 */
 151         dissector_add_string("media_type", "text/parameters", text_lines_handle);
 152         /* W3C line-based textual media */
 153         dissector_add_string("media_type", "text/html", text_lines_handle);
 154         dissector_add_string("media_type", "text/xml-external-parsed-entity", text_lines_handle);
 155         dissector_add_string("media_type", "text/css", text_lines_handle);
 156         dissector_add_string("media_type", "application/xml-external-parsed-entity", text_lines_handle);
 157         dissector_add_string("media_type", "text/javascript", text_lines_handle);
 158         dissector_add_string("media_type", "application/x-javascript", text_lines_handle);
 159         dissector_add_string("media_type", "application/x-tia-p25-issi", text_lines_handle);
 160         dissector_add_string("media_type", "application/x-tia-p25-sndcp", text_lines_handle);
 161         dissector_add_string("media_type", "application/x-ns-proxy-autoconfig", text_lines_handle);
 162
 163         dissector_add_string("media_type", "text/vnd.sun.j2me.app-descriptor", text_lines_handle);
 164         dissector_add_string("media_type", "application/vnd.poc.refer-to", text_lines_handle);
 165         dissector_add_string("media_type", "application/vnd.drm.message", text_lines_handle);
 166
 167         dissector_add_string("media_type", "application/x-wms-logplaystats", text_lines_handle);
 168         dissector_add_string("media_type", "application/x-rtsp-udp-packetpair", text_lines_handle);
 169         xml_handle = find_dissector_add_dependency("xml", proto_text_lines);
 170 }
 171
 172 /*
 173  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 174  *
 175  * Local variables:
 176  * c-basic-offset: 8
 177  * tab-width: 8
 178  * indent-tabs-mode: t
 179  * End:
 180  *
 181  * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 182  * :indentSize=8:tabSize=8:noTabs=false:
 183  */