1999-07-07 00:34:58 +00:00
|
|
|
/* packet-sdp.c
|
2000-01-13 03:18:34 +00:00
|
|
|
* Routines for SDP packet disassembly (RFC 2327)
|
1999-07-07 00:34:58 +00:00
|
|
|
*
|
|
|
|
* Jason Lango <jal@netapp.com>
|
2000-01-22 06:22:44 +00:00
|
|
|
* Liberally copied from packet-http.c, by Guy Harris <guy@alum.mit.edu>
|
1999-07-07 00:34:58 +00:00
|
|
|
*
|
2001-01-09 06:32:10 +00:00
|
|
|
* $Id: packet-sdp.c,v 1.19 2001/01/09 06:31:43 guy Exp $
|
1999-07-07 00:34:58 +00:00
|
|
|
*
|
|
|
|
* Ethereal - Network traffic analyzer
|
|
|
|
* By Gerald Combs <gerald@zing.org>
|
|
|
|
* Copyright 1998 Gerald Combs
|
|
|
|
*
|
|
|
|
*
|
|
|
|
* This program is free software; you can redistribute it and/or
|
|
|
|
* modify it under the terms of the GNU General Public License
|
|
|
|
* as published by the Free Software Foundation; either version 2
|
|
|
|
* of the License, or (at your option) any later version.
|
|
|
|
*
|
|
|
|
* This program is distributed in the hope that it will be useful,
|
|
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
|
* GNU General Public License for more details.
|
|
|
|
*
|
|
|
|
* You should have received a copy of the GNU General Public License
|
|
|
|
* along with this program; if not, write to the Free Software
|
|
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
*
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include "config.h"
|
|
|
|
|
|
|
|
#ifdef HAVE_SYS_TYPES_H
|
|
|
|
#include <sys/types.h>
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#include <string.h>
|
|
|
|
#include <ctype.h>
|
|
|
|
|
|
|
|
#include <glib.h>
|
|
|
|
#include "packet.h"
|
2000-09-11 16:16:13 +00:00
|
|
|
#include "strutil.h"
|
1999-07-07 00:34:58 +00:00
|
|
|
|
1999-07-29 05:47:07 +00:00
|
|
|
static int proto_sdp = -1;
|
|
|
|
|
1999-11-16 11:44:20 +00:00
|
|
|
static int ett_sdp = -1;
|
|
|
|
|
Add a mechanism by which a dissector can be registered by name, another
dissector can get a "handle" for that dissector by name and then call
that dissector through the handle.
This allows dissectors that can't be called through a port table or a
heuristic table to be called from other dissectors without directly
referring to the dissector function - dynamically-loaded modules, under
Windows, cannot directly call functions in the main program, and
non-plugin dissectors are in the main program and thus cannot be called
from plugin dissectors unless either
1) a pointer to the dissector is put in the Big Transfer Vector
or
2) some other mechanism for getting a pointer to the dissector
is provided.
This mechanism could also support registering old-style dissectors and
calling them from new-style dissectors without the new-style dissector
having to do the argument translation itself (I didn't add support for
registering old-style dissectors because I'd prefer to have people
tvbuffify their code if they have to register a dissector...).
It could also, in the future, perhaps support
disabling of protocols;
setting "pinfo->current_proto";
inside "call_dissector()" - and inside "{old_}dissector_try_port()" and
"{old_"dissector_try_heuristic()" - allowing a pile of stuff that
currently has to be done in every dissector be done by common code.
(I have some ideas about how to do this, by
having "proto_register_protocol()" take an abbreviation - of the
sort that would be put in, for example, "pinfo->current_proto" -
as an argument;
having the calls to register dissectors take an index returned
by "proto_register_protocol()" as an argument.
The abbreviation could be used elsewhere as well, e.g. in the "Decoding"
tab of the "Edit->Protocols" dialog box, and in a GUI for constructing
protocol filters. Watch this space.)
Make "dissect_sdp()" the first client of this mechanism; it's now static
to "packet-sdp.c", and all dissectors that call it - including the MGCP
plugin - now call it through a dissector handle fetched by
"find_dissector()". (Next step - see if Ethereal can now compile on
Windows as a result of this.)
svn path=/trunk/; revision=2647
2000-11-15 07:07:52 +00:00
|
|
|
static void
|
2000-11-10 06:50:37 +00:00
|
|
|
dissect_sdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
|
1999-07-07 00:34:58 +00:00
|
|
|
{
|
|
|
|
proto_tree *sdp_tree;
|
|
|
|
proto_item *ti;
|
2000-11-10 06:50:37 +00:00
|
|
|
gint offset = 0;
|
|
|
|
const u_char *line;
|
|
|
|
gint next_offset;
|
1999-07-07 00:34:58 +00:00
|
|
|
int linelen;
|
|
|
|
u_char section;
|
|
|
|
u_char type;
|
|
|
|
const u_char *value;
|
|
|
|
int valuelen;
|
|
|
|
const char *typename;
|
2000-11-10 06:50:37 +00:00
|
|
|
int datalen;
|
1999-07-07 00:34:58 +00:00
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
CHECK_DISPLAY_AS_DATA(proto_sdp, tvb, pinfo, tree);
|
Add the "Edit:Protocols..." feature which currently only implements
the following:
It is now possible to enable/disable a particular protocol decoding
(i.e. the protocol dissector is void or not). When a protocol
is disabled, it is displayed as Data and of course, all linked
sub-protocols are disabled as well.
Disabling a protocol could be interesting:
- in case of buggy dissectors
- in case of wrong heuristics
- for performance reasons
- to decode the data as another protocol (TODO)
Currently (if I am not wrong), all dissectors but NFS can be disabled
(and dissectors that do not register protocols :-)
I do not like the way the RPC sub-dissectors are disabled (in the
sub-dissectors) since this could be done in the RPC dissector itself,
knowing the sub-protocol hfinfo entry (this is why, I've not modified
the NFS one yet).
Two functions are added in proto.c :
gboolean proto_is_protocol_enabled(int n);
void proto_set_decoding(int n, gboolean enabled);
and two MACROs which can be used in dissectors:
OLD_CHECK_DISPLAY_AS_DATA(index, pd, offset, fd, tree)
CHECK_DISPLAY_AS_DATA(index, tvb, pinfo, tree)
See also the XXX in proto_dlg.c and proto.c around the new functions.
svn path=/trunk/; revision=2267
2000-08-13 14:09:15 +00:00
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
pinfo->current_proto = "SDP";
|
1999-07-07 00:34:58 +00:00
|
|
|
|
2000-11-13 01:43:02 +00:00
|
|
|
/*
|
|
|
|
* As RFC 2327 says, "SDP is purely a format for session
|
|
|
|
* description - it does not incorporate a transport protocol,
|
|
|
|
* and is intended to use different transport protocols as
|
|
|
|
* appropriate including the Session Announcement Protocol,
|
|
|
|
* Session Initiation Protocol, Real-Time Streaming Protocol,
|
|
|
|
* electronic mail using the MIME extensions, and the
|
|
|
|
* Hypertext Transport Protocol."
|
|
|
|
*
|
|
|
|
* We therefore don't set the protocol or info columns;
|
|
|
|
* instead, we append to them, so that we don't erase
|
|
|
|
* what the protocol inside which the SDP stuff resides
|
|
|
|
* put there.
|
|
|
|
*/
|
2000-11-10 06:50:37 +00:00
|
|
|
if (check_col(pinfo->fd, COL_PROTOCOL))
|
As RFC 2327 says, "SDP is purely a format for session description - it
does not incorporate a transport protocol, and is intended to use
different transport protocols as appropriate including the Session
Announcement Protocol [4], Session Initiation Protocol [11], Real- Time
Streaming Protocol [12], electronic mail using the MIME extensions, and
the Hypertext Transport Protocol."
As such, it shouldn't set the protocol column to SDP, as that means
the protocol column won't indicate what the transport protocol was;
instead, it should append "/SDP" to the protocol column - RTSP was,
after calling "dissect_sdp()", setting the protocol column to
"RTSP/SDP", and this change means that all protocols using SDP will have
the protocol column set in that fashion, and that the RTSP dissector
doesn't have to explicitly set the protocol column to cause that to
happen.
svn path=/trunk/; revision=2624
2000-11-12 21:23:53 +00:00
|
|
|
col_append_str(pinfo->fd, COL_PROTOCOL, "/SDP");
|
1999-07-07 00:34:58 +00:00
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
if (check_col(pinfo->fd, COL_INFO)) {
|
1999-07-07 00:34:58 +00:00
|
|
|
/* XXX: Needs description. */
|
2000-11-13 01:43:02 +00:00
|
|
|
col_append_str(pinfo->fd, COL_INFO, ", with session description");
|
1999-07-07 00:34:58 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
if (!tree)
|
|
|
|
return;
|
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
ti = proto_tree_add_item(tree, proto_sdp, tvb, offset,
|
|
|
|
tvb_length_remaining(tvb, offset), FALSE);
|
1999-11-16 11:44:20 +00:00
|
|
|
sdp_tree = proto_item_add_subtree(ti, ett_sdp);
|
1999-07-07 00:34:58 +00:00
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
/*
|
|
|
|
* Show the SDP message a line at a time.
|
|
|
|
*/
|
1999-07-07 00:34:58 +00:00
|
|
|
section = 0;
|
2000-11-13 08:58:17 +00:00
|
|
|
while (tvb_offset_exists(tvb, offset)) {
|
1999-07-07 00:34:58 +00:00
|
|
|
/*
|
|
|
|
* Find the end of the line.
|
|
|
|
*/
|
2000-11-10 06:50:37 +00:00
|
|
|
linelen = tvb_find_line_end_unquoted(tvb, offset, -1,
|
|
|
|
&next_offset);
|
1999-07-07 00:34:58 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Line must contain at least e.g. "v=".
|
|
|
|
*/
|
|
|
|
if (linelen < 2)
|
|
|
|
break;
|
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
line = tvb_get_ptr(tvb, offset, next_offset - offset);
|
|
|
|
type = line[0];
|
|
|
|
if (line[1] != '=') {
|
|
|
|
proto_tree_add_text(sdp_tree, tvb, offset,
|
|
|
|
next_offset - offset,
|
|
|
|
"Invalid line: %s",
|
|
|
|
tvb_format_text(tvb, offset, next_offset - offset));
|
2000-11-19 21:01:06 +00:00
|
|
|
offset = next_offset;
|
1999-07-07 00:34:58 +00:00
|
|
|
continue;
|
|
|
|
}
|
2000-11-10 06:50:37 +00:00
|
|
|
value = line + 2;
|
1999-07-07 00:34:58 +00:00
|
|
|
valuelen = linelen - 2;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Attributes.
|
|
|
|
*/
|
|
|
|
switch (type) {
|
|
|
|
case 'v':
|
|
|
|
section = 'v';
|
|
|
|
typename = "Session Description, version";
|
|
|
|
break;
|
|
|
|
case 'o':
|
|
|
|
typename = "Owner/Creator, Session Id";
|
|
|
|
break;
|
|
|
|
case 's':
|
|
|
|
typename = "Session Name";
|
|
|
|
break;
|
|
|
|
case 'i':
|
|
|
|
if (section == 'v')
|
|
|
|
typename = "Session Information";
|
|
|
|
else if (section == 'm')
|
|
|
|
typename = "Media Title";
|
|
|
|
else
|
|
|
|
typename = "Misplaced";
|
|
|
|
break;
|
|
|
|
case 'u':
|
|
|
|
typename = "URI of Description";
|
|
|
|
break;
|
|
|
|
case 'e':
|
|
|
|
typename = "E-mail Address";
|
|
|
|
break;
|
|
|
|
case 'p':
|
|
|
|
typename = "Phone Number";
|
|
|
|
break;
|
|
|
|
case 'c':
|
|
|
|
typename = "Connection Information";
|
|
|
|
break;
|
|
|
|
case 'b':
|
|
|
|
typename = "Bandwidth Information";
|
|
|
|
break;
|
|
|
|
case 't':
|
|
|
|
section = 't';
|
|
|
|
typename = "Time Description, active time";
|
|
|
|
break;
|
|
|
|
case 'r':
|
|
|
|
typename = "Repeat Time";
|
|
|
|
break;
|
|
|
|
case 'm':
|
|
|
|
section = 'm';
|
|
|
|
typename = "Media Description, name and address";
|
|
|
|
break;
|
|
|
|
case 'k':
|
|
|
|
typename = "Encryption Key";
|
|
|
|
break;
|
|
|
|
case 'a':
|
|
|
|
if (section == 'v')
|
|
|
|
typename = "Session Attribute";
|
|
|
|
else if (section == 'm')
|
|
|
|
typename = "Media Attribute";
|
|
|
|
else
|
|
|
|
typename = "Misplaced";
|
|
|
|
break;
|
|
|
|
case 'z':
|
|
|
|
typename = "Time Zone Adjustment";
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
typename = "Unknown";
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
proto_tree_add_text(sdp_tree, tvb, offset,
|
|
|
|
next_offset - offset,
|
|
|
|
"%s (%c): %s", typename, type,
|
|
|
|
format_text(value, valuelen));
|
|
|
|
offset = next_offset;
|
1999-07-07 00:34:58 +00:00
|
|
|
}
|
|
|
|
|
2000-11-10 06:50:37 +00:00
|
|
|
datalen = tvb_length_remaining(tvb, offset);
|
|
|
|
if (datalen > 0) {
|
|
|
|
proto_tree_add_text(sdp_tree, tvb, offset, datalen,
|
|
|
|
"Data (%d bytes)", datalen);
|
1999-07-07 00:34:58 +00:00
|
|
|
}
|
|
|
|
}
|
1999-07-29 05:47:07 +00:00
|
|
|
|
|
|
|
void
|
|
|
|
proto_register_sdp(void)
|
|
|
|
{
|
|
|
|
/* static hf_register_info hf[] = {
|
|
|
|
{ &variable,
|
|
|
|
{ "Name", "sdp.abbreviation", TYPE, VALS_POINTER }},
|
|
|
|
};*/
|
1999-11-16 11:44:20 +00:00
|
|
|
static gint *ett[] = {
|
|
|
|
&ett_sdp,
|
|
|
|
};
|
1999-07-29 05:47:07 +00:00
|
|
|
|
2001-01-03 06:56:03 +00:00
|
|
|
proto_sdp = proto_register_protocol("Session Description Protocol",
|
|
|
|
"SDP", "sdp");
|
1999-07-29 05:47:07 +00:00
|
|
|
/* proto_register_field_array(proto_sdp, hf, array_length(hf));*/
|
1999-11-16 11:44:20 +00:00
|
|
|
proto_register_subtree_array(ett, array_length(ett));
|
Add a mechanism by which a dissector can be registered by name, another
dissector can get a "handle" for that dissector by name and then call
that dissector through the handle.
This allows dissectors that can't be called through a port table or a
heuristic table to be called from other dissectors without directly
referring to the dissector function - dynamically-loaded modules, under
Windows, cannot directly call functions in the main program, and
non-plugin dissectors are in the main program and thus cannot be called
from plugin dissectors unless either
1) a pointer to the dissector is put in the Big Transfer Vector
or
2) some other mechanism for getting a pointer to the dissector
is provided.
This mechanism could also support registering old-style dissectors and
calling them from new-style dissectors without the new-style dissector
having to do the argument translation itself (I didn't add support for
registering old-style dissectors because I'd prefer to have people
tvbuffify their code if they have to register a dissector...).
It could also, in the future, perhaps support
disabling of protocols;
setting "pinfo->current_proto";
inside "call_dissector()" - and inside "{old_}dissector_try_port()" and
"{old_"dissector_try_heuristic()" - allowing a pile of stuff that
currently has to be done in every dissector be done by common code.
(I have some ideas about how to do this, by
having "proto_register_protocol()" take an abbreviation - of the
sort that would be put in, for example, "pinfo->current_proto" -
as an argument;
having the calls to register dissectors take an index returned
by "proto_register_protocol()" as an argument.
The abbreviation could be used elsewhere as well, e.g. in the "Decoding"
tab of the "Edit->Protocols" dialog box, and in a GUI for constructing
protocol filters. Watch this space.)
Make "dissect_sdp()" the first client of this mechanism; it's now static
to "packet-sdp.c", and all dissectors that call it - including the MGCP
plugin - now call it through a dissector handle fetched by
"find_dissector()". (Next step - see if Ethereal can now compile on
Windows as a result of this.)
svn path=/trunk/; revision=2647
2000-11-15 07:07:52 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Register the dissector by name, so other dissectors can
|
|
|
|
* grab it by name rather than just referring to it directly
|
|
|
|
* (you can't refer to it directly from a plugin dissector
|
|
|
|
* on Windows without stuffing it into the Big Transfer Vector).
|
|
|
|
*/
|
2001-01-09 06:32:10 +00:00
|
|
|
register_dissector("sdp", dissect_sdp, proto_sdp);
|
1999-07-29 05:47:07 +00:00
|
|
|
}
|