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/* packet-media.c
* Routines for displaying an undissected media type (default case),
* based on the generic "data" dissector.
*
* (C) Olivier Biot, 2004
*
* Refer to the AUTHORS file or the AUTHORS section in the man page
* for contacting the author(s) of this file.
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <epan/packet.h>
#include <wsutil/str_util.h>
#include "packet-media-type.h"
void proto_register_media(void);
static int proto_media;
static int hf_media_type;
static int ett_media;
static heur_dissector_list_t heur_subdissector_list;
static dissector_table_t media_type_suffix_table;
static int
dissect_media(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
{
int bytes;
proto_item *ti;
proto_tree *media_tree = 0;
media_content_info_t *content_info = (media_content_info_t *)data;
heur_dtbl_entry_t *hdtbl_entry;
char* suffix;
/* XXX - Should we move the other media_type table here, and have
* dissectors always call this dissector instead of invoking the table,
* similar to the Ethertype dissector?
* It would make Decode As with Media Types easier.
*/
/*
* RFC 6838 4.2 Naming Requirements
* "Characters after last plus always specify a structured syntax suffix"
*/
if (pinfo->match_string &&
(suffix = strrchr(pinfo->match_string, '+'))) {
if ((bytes = dissector_try_string_new(media_type_suffix_table,
suffix + 1, tvb, pinfo, tree, true, data)) > 0) {
return bytes;
}
}
if (dissector_try_heuristic(heur_subdissector_list, tvb, pinfo, tree, &hdtbl_entry, data)) {
return tvb_reported_length(tvb);
}
/* Add media type to the INFO column if it is visible */
col_append_fstr(pinfo->cinfo, COL_INFO, " (%s)", (pinfo->match_string) ? pinfo->match_string : "");
if (tree) {
if ( (bytes = tvb_reported_length(tvb)) > 0 )
{
ti = proto_tree_add_item(tree, proto_media, tvb, 0, -1, ENC_NA);
media_tree = proto_item_add_subtree(ti, ett_media);
if (content_info != NULL && content_info->media_str != NULL) {
/* The media type has parameters */
proto_tree_add_bytes_format_value(media_tree, hf_media_type, tvb, 0, bytes,
NULL, "%s; %s (%d byte%s)",
pinfo->match_string, content_info->media_str,
bytes, plurality(bytes, "", "s"));
} else {
/* The media type has no parameters */
proto_tree_add_bytes_format_value(media_tree, hf_media_type, tvb, 0, bytes,
NULL, "%s (%d byte%s)",
pinfo->match_string ? pinfo->match_string : "",
bytes, plurality(bytes, "", "s"));
}
}
}
return tvb_reported_length(tvb);
}
void
proto_register_media(void)
{
static hf_register_info hf[] = {
{ &hf_media_type,
{ "Media type", "media.type",
FT_BYTES, BASE_NONE, NULL, 0,
NULL, HFILL }},
};
static int *ett[] = {
&ett_media
};
proto_media = proto_register_protocol (
"Media Type", /* name */
"Media", /* short name */
"media" /* abbrev */
);
register_dissector("media", dissect_media, proto_media);
heur_subdissector_list = register_heur_dissector_list_with_description("media", "Media type", proto_media);
proto_register_field_array(proto_media, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
/*
* "Media" is used to dissect something whose normal dissector
* is disabled, so it cannot itself be disabled.
*/
proto_set_cant_toggle(proto_media);
/*
* https://www.iana.org/assignments/media-type-structured-suffix/media-type-structured-suffix.xhtml
* Structured Suffixes ("zzz" in "xxx/yyy+zzz") can be used as fallback
* when the exact media type is not registered.
*/
media_type_suffix_table = register_dissector_table("media_type.suffix",
"Internet media type structured suffix",
proto_media, FT_STRING, STRING_CASE_INSENSITIVE);
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/
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