forked from osmocom/wireshark
![Jörg Mayer](/assets/img/avatar_default.png)
winapi_cleanup tool written by Patrik Stridvall for the wine project. svn path=/trunk/; revision=6117
1228 lines
30 KiB
C
1228 lines
30 KiB
C
/* packet-rtcp.c
|
|
*
|
|
* $Id: packet-rtcp.c,v 1.35 2002/08/28 21:00:29 jmayer Exp $
|
|
*
|
|
* Routines for RTCP dissection
|
|
* RTCP = Real-time Transport Control Protocol
|
|
*
|
|
* Copyright 2000, Philips Electronics N.V.
|
|
* Written by Andreas Sikkema <andreas.sikkema@philips.com>
|
|
*
|
|
* Ethereal - Network traffic analyzer
|
|
* By Gerald Combs <gerald@ethereal.com>
|
|
* 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.
|
|
*/
|
|
|
|
/*
|
|
* This dissector tries to dissect the RTCP protocol according to Annex A
|
|
* of ITU-T Recommendation H.225.0 (02/98) and RFC 1889
|
|
* H.225.0 literally copies RFC 1889, but omitting a few sections.
|
|
*
|
|
* RTCP traffic is handled by an uneven UDP portnumber. This can be any
|
|
* port number, but there is a registered port available, port 5005
|
|
* See Annex B of ITU-T Recommendation H.225.0, section B.7
|
|
*
|
|
*/
|
|
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
# include "config.h"
|
|
#endif
|
|
|
|
#include <glib.h>
|
|
#include <epan/packet.h>
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
#include "packet-rtcp.h"
|
|
#if 0
|
|
#include "packet-ntp.h"
|
|
#endif
|
|
#include <epan/conversation.h>
|
|
|
|
/* Version is the first 2 bits of the first octet*/
|
|
#define RTCP_VERSION(octet) ((octet) >> 6)
|
|
|
|
/* Padding is the third bit; no need to shift, because true is any value
|
|
other than 0! */
|
|
#define RTCP_PADDING(octet) ((octet) & 0x20)
|
|
|
|
/* Receiver/ Sender count is the 5 last bits */
|
|
#define RTCP_COUNT(octet) ((octet) & 0x1F)
|
|
|
|
static const value_string rtcp_version_vals[] =
|
|
{
|
|
{ 0, "Old VAT Version" },
|
|
{ 1, "First Draft Version" },
|
|
{ 2, "RFC 1889 Version" },
|
|
{ 0, NULL },
|
|
};
|
|
|
|
/* RTCP packet types according to Section A.11.1 */
|
|
#define RTCP_SR 200
|
|
#define RTCP_RR 201
|
|
#define RTCP_SDES 202
|
|
#define RTCP_BYE 203
|
|
#define RTCP_APP 204
|
|
/* Supplemental H.261 specific RTCP packet types according to Section C.3.5 */
|
|
#define RTCP_FIR 192
|
|
#define RTCP_NACK 193
|
|
|
|
static const value_string rtcp_packet_type_vals[] =
|
|
{
|
|
{ RTCP_SR, "Sender Report" },
|
|
{ RTCP_RR, "Receiver Report" },
|
|
{ RTCP_SDES, "Source description" },
|
|
{ RTCP_BYE, "Goodbye" },
|
|
{ RTCP_APP, "Application specific" },
|
|
{ RTCP_FIR, "Full Intra-frame Request (H.261)" },
|
|
{ RTCP_NACK, "Negative Acknowledgement (H.261)" },
|
|
{ 0, NULL },
|
|
};
|
|
|
|
/* RTCP SDES types (Section A.11.2) */
|
|
#define RTCP_SDES_END 0
|
|
#define RTCP_SDES_CNAME 1
|
|
#define RTCP_SDES_NAME 2
|
|
#define RTCP_SDES_EMAIL 3
|
|
#define RTCP_SDES_PHONE 4
|
|
#define RTCP_SDES_LOC 5
|
|
#define RTCP_SDES_TOOL 6
|
|
#define RTCP_SDES_NOTE 7
|
|
#define RTCP_SDES_PRIV 8
|
|
|
|
static const value_string rtcp_sdes_type_vals[] =
|
|
{
|
|
{ RTCP_SDES_END, "END" },
|
|
{ RTCP_SDES_CNAME, "CNAME (user and domain)" },
|
|
{ RTCP_SDES_NAME, "NAME (common name)" },
|
|
{ RTCP_SDES_EMAIL, "EMAIL (e-mail address)" },
|
|
{ RTCP_SDES_PHONE, "PHONE (phone number)" },
|
|
{ RTCP_SDES_LOC, "LOC (geographic location)" },
|
|
{ RTCP_SDES_TOOL, "TOOL (name/version of source app)" },
|
|
{ RTCP_SDES_NOTE, "NOTE (note about source)" },
|
|
{ RTCP_SDES_PRIV, "PRIV (private extensions)" },
|
|
{ 0, NULL },
|
|
};
|
|
|
|
/* RTCP header fields */
|
|
static int proto_rtcp = -1;
|
|
static int hf_rtcp_version = -1;
|
|
static int hf_rtcp_padding = -1;
|
|
static int hf_rtcp_rc = -1;
|
|
static int hf_rtcp_sc = -1;
|
|
static int hf_rtcp_pt = -1;
|
|
static int hf_rtcp_length = -1;
|
|
static int hf_rtcp_ssrc_sender = -1;
|
|
static int hf_rtcp_ntp = -1;
|
|
static int hf_rtcp_rtp_timestamp = -1;
|
|
static int hf_rtcp_sender_pkt_cnt = -1;
|
|
static int hf_rtcp_sender_oct_cnt = -1;
|
|
static int hf_rtcp_ssrc_source = -1;
|
|
static int hf_rtcp_ssrc_fraction = -1;
|
|
static int hf_rtcp_ssrc_cum_nr = -1;
|
|
/* First the 32 bit number, then the split
|
|
* up 16 bit values */
|
|
/* These two are added to a subtree */
|
|
static int hf_rtcp_ssrc_ext_high_seq = -1;
|
|
static int hf_rtcp_ssrc_high_seq = -1;
|
|
static int hf_rtcp_ssrc_high_cycles = -1;
|
|
static int hf_rtcp_ssrc_jitter = -1;
|
|
static int hf_rtcp_ssrc_lsr = -1;
|
|
static int hf_rtcp_ssrc_dlsr = -1;
|
|
static int hf_rtcp_ssrc_csrc = -1;
|
|
static int hf_rtcp_ssrc_type = -1;
|
|
static int hf_rtcp_ssrc_length = -1;
|
|
static int hf_rtcp_ssrc_text = -1;
|
|
static int hf_rtcp_ssrc_prefix_len = -1;
|
|
static int hf_rtcp_ssrc_prefix_string= -1;
|
|
static int hf_rtcp_subtype = -1;
|
|
static int hf_rtcp_name_ascii = -1;
|
|
static int hf_rtcp_app_data = -1;
|
|
static int hf_rtcp_fsn = -1;
|
|
static int hf_rtcp_blp = -1;
|
|
static int hf_rtcp_padding_count = -1;
|
|
static int hf_rtcp_padding_data = -1;
|
|
|
|
/* RTCP fields defining a sub tree */
|
|
static gint ett_rtcp = -1;
|
|
static gint ett_ssrc = -1;
|
|
static gint ett_ssrc_item = -1;
|
|
static gint ett_ssrc_ext_high = -1;
|
|
static gint ett_sdes = -1;
|
|
static gint ett_sdes_item = -1;
|
|
|
|
static address fake_addr;
|
|
static int heur_init = FALSE;
|
|
|
|
static gboolean dissect_rtcp_heur( tvbuff_t *tvb, packet_info *pinfo,
|
|
proto_tree *tree );
|
|
static void dissect_rtcp( tvbuff_t *tvb, packet_info *pinfo,
|
|
proto_tree *tree );
|
|
|
|
void rtcp_add_address( packet_info *pinfo, const unsigned char* ip_addr,
|
|
int prt )
|
|
{
|
|
address src_addr;
|
|
conversation_t* pconv;
|
|
|
|
/*
|
|
* If this isn't the first time this packet has been processed,
|
|
* we've already done this work, so we don't need to do it
|
|
* again.
|
|
*/
|
|
if (pinfo->fd->flags.visited)
|
|
return;
|
|
|
|
src_addr.type = AT_IPv4;
|
|
src_addr.len = 4;
|
|
src_addr.data = ip_addr;
|
|
|
|
/*
|
|
* The first time the function is called let the udp dissector
|
|
* know that we're interested in traffic
|
|
*/
|
|
if ( ! heur_init ) {
|
|
heur_dissector_add( "udp", dissect_rtcp_heur, proto_rtcp );
|
|
heur_init = TRUE;
|
|
}
|
|
|
|
/*
|
|
* Check if the ip address and port combination is not
|
|
* already registered
|
|
*/
|
|
pconv = find_conversation( &src_addr, &fake_addr, PT_UDP, prt, 0, 0 );
|
|
|
|
/*
|
|
* If not, add
|
|
* XXX - use wildcard address and port B?
|
|
*/
|
|
if ( ! pconv ) {
|
|
pconv = conversation_new( &src_addr, &fake_addr, PT_UDP,
|
|
(guint32) prt, (guint32) 0, 0 );
|
|
conversation_add_proto_data(pconv, proto_rtcp, NULL);
|
|
}
|
|
|
|
}
|
|
|
|
#if 0
|
|
static void rtcp_init( void )
|
|
{
|
|
unsigned char* tmp_data;
|
|
int i;
|
|
|
|
/* Create a fake adddress... */
|
|
fake_addr.type = AT_IPv4;
|
|
fake_addr.len = 4;
|
|
|
|
tmp_data = malloc( fake_addr.len );
|
|
for ( i = 0; i < fake_addr.len; i++) {
|
|
tmp_data[i] = 0;
|
|
}
|
|
fake_addr.data = tmp_data;
|
|
}
|
|
#endif
|
|
|
|
static gboolean
|
|
dissect_rtcp_heur( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
|
|
{
|
|
conversation_t* pconv;
|
|
|
|
/* This is a heuristic dissector, which means we get all the UDP
|
|
* traffic not sent to a known dissector and not claimed by
|
|
* a heuristic dissector called before us!
|
|
* So we first check if the frame is really meant for us.
|
|
*/
|
|
if ( ( pconv = find_conversation( &pinfo->src, &fake_addr, pinfo->ptype,
|
|
pinfo->srcport, 0, 0 ) ) == NULL ) {
|
|
/*
|
|
* The source ip:port combination was not what we were
|
|
* looking for, check the destination
|
|
*/
|
|
if ( ( pconv = find_conversation( &pinfo->dst, &fake_addr,
|
|
pinfo->ptype, pinfo->destport, 0, 0 ) ) == NULL ) {
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* An RTCP conversation always has a data item for RTCP.
|
|
* (Its existence is sufficient to indicate that this is an RTCP
|
|
* conversation.)
|
|
*/
|
|
if (conversation_get_proto_data(pconv, proto_rtcp) == NULL)
|
|
return FALSE;
|
|
|
|
/*
|
|
* The message is a valid RTCP message!
|
|
*/
|
|
dissect_rtcp( tvb, pinfo, tree );
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
|
|
static int
|
|
dissect_rtcp_nack( tvbuff_t *tvb, int offset, proto_tree *tree )
|
|
{
|
|
/* Packet type = FIR (H261) */
|
|
proto_tree_add_uint( tree, hf_rtcp_rc, tvb, offset, 1, tvb_get_guint8( tvb, offset ) & 31 );
|
|
offset++;
|
|
/* Packet type, 8 bits = APP */
|
|
proto_tree_add_item( tree, hf_rtcp_pt, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
|
|
/* Packet length in 32 bit words minus one */
|
|
proto_tree_add_uint( tree, hf_rtcp_length, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
|
|
/* SSRC */
|
|
proto_tree_add_uint( tree, hf_rtcp_ssrc_source, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
/* FSN, 16 bits */
|
|
proto_tree_add_uint( tree, hf_rtcp_fsn, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
|
|
/* BLP, 16 bits */
|
|
proto_tree_add_uint( tree, hf_rtcp_blp, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_rtcp_fir( tvbuff_t *tvb, int offset, proto_tree *tree )
|
|
{
|
|
/* Packet type = FIR (H261) */
|
|
proto_tree_add_uint( tree, hf_rtcp_rc, tvb, offset, 1, tvb_get_guint8( tvb, offset ) & 31 );
|
|
offset++;
|
|
/* Packet type, 8 bits = APP */
|
|
proto_tree_add_item( tree, hf_rtcp_pt, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
|
|
/* Packet length in 32 bit words minus one */
|
|
proto_tree_add_uint( tree, hf_rtcp_length, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
|
|
/* SSRC */
|
|
proto_tree_add_uint( tree, hf_rtcp_ssrc_source, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_rtcp_app( tvbuff_t *tvb, int offset, proto_tree *tree,
|
|
unsigned int padding, unsigned int packet_len )
|
|
{
|
|
unsigned int counter = 0;
|
|
char ascii_name[5];
|
|
|
|
/* SSRC / CSRC */
|
|
proto_tree_add_uint( tree, hf_rtcp_ssrc_source, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
packet_len -= 4;
|
|
|
|
/* Name (ASCII) */
|
|
for( counter = 0; counter < 4; counter++ )
|
|
ascii_name[ counter ] = tvb_get_guint8( tvb, offset + counter );
|
|
/* strncpy( ascii_name, pd + offset, 4 ); */
|
|
ascii_name[4] = '\0';
|
|
proto_tree_add_string( tree, hf_rtcp_name_ascii, tvb, offset, 4,
|
|
ascii_name );
|
|
offset += 4;
|
|
packet_len -= 4;
|
|
|
|
/* Applications specific data */
|
|
if ( padding ) {
|
|
/* If there's padding present, we have to remove that from the data part
|
|
* The last octet of the packet contains the length of the padding
|
|
*/
|
|
packet_len -= tvb_get_guint8( tvb, offset + packet_len - 1 );
|
|
}
|
|
proto_tree_add_item( tree, hf_rtcp_app_data, tvb, offset, packet_len, FALSE );
|
|
offset += packet_len;
|
|
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_rtcp_bye( tvbuff_t *tvb, int offset, proto_tree *tree,
|
|
unsigned int count )
|
|
{
|
|
unsigned int chunk = 1;
|
|
unsigned int reason_length = 0;
|
|
unsigned int counter = 0;
|
|
char* reason_text = NULL;
|
|
|
|
while ( chunk <= count ) {
|
|
/* source identifier, 32 bits */
|
|
proto_tree_add_item( tree, hf_rtcp_ssrc_source, tvb, offset, 4, FALSE);
|
|
offset += 4;
|
|
chunk++;
|
|
}
|
|
|
|
if ( tvb_reported_length_remaining( tvb, offset ) > 0 ) {
|
|
/* Bye reason consists of an 8 bit length l and a string with length l */
|
|
reason_length = tvb_get_guint8( tvb, offset );
|
|
proto_tree_add_item( tree, hf_rtcp_ssrc_length, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
|
|
reason_text = ( char* ) malloc( reason_length + 1 );
|
|
for ( counter = 0; counter < reason_length; counter++ ) reason_text[ counter ] = tvb_get_guint8( tvb, offset + counter );
|
|
/* strncpy( reason_text, pd + offset, reason_length ); */
|
|
reason_text[ reason_length ] = '\0';
|
|
proto_tree_add_string( tree, hf_rtcp_ssrc_text, tvb, offset, reason_length, reason_text );
|
|
free( reason_text );
|
|
offset += reason_length;
|
|
}
|
|
|
|
return offset;
|
|
|
|
}
|
|
|
|
static void
|
|
dissect_rtcp_sdes( tvbuff_t *tvb, int offset, proto_tree *tree,
|
|
unsigned int count )
|
|
{
|
|
unsigned int chunk = 1;
|
|
proto_item *sdes_item;
|
|
proto_tree *sdes_tree;
|
|
proto_tree *sdes_item_tree;
|
|
proto_item *ti;
|
|
int start_offset;
|
|
int items_start_offset;
|
|
guint32 ssrc;
|
|
unsigned int item_len = 0;
|
|
unsigned int sdes_type = 0;
|
|
unsigned int counter = 0;
|
|
unsigned int prefix_len = 0;
|
|
char *prefix_string = NULL;
|
|
|
|
while ( chunk <= count ) {
|
|
/* Create a subtree for this chunk; we don't yet know
|
|
the length. */
|
|
start_offset = offset;
|
|
|
|
ssrc = tvb_get_ntohl( tvb, offset );
|
|
sdes_item = proto_tree_add_text(tree, tvb, offset, -1,
|
|
"Chunk %u, SSRC/CSRC %u", chunk, ssrc);
|
|
sdes_tree = proto_item_add_subtree( sdes_item, ett_sdes );
|
|
|
|
/* SSRC_n source identifier, 32 bits */
|
|
proto_tree_add_uint( sdes_tree, hf_rtcp_ssrc_source, tvb, offset, 4, ssrc );
|
|
offset += 4;
|
|
|
|
/* Create a subtree for the SDES items; we don't yet know
|
|
the length */
|
|
items_start_offset = offset;
|
|
ti = proto_tree_add_text(sdes_tree, tvb, offset, -1,
|
|
"SDES items" );
|
|
sdes_item_tree = proto_item_add_subtree( ti, ett_sdes_item );
|
|
|
|
/*
|
|
* Not every message is ended with "null" bytes, so check for
|
|
* end of frame instead.
|
|
*/
|
|
while ( ( tvb_reported_length_remaining( tvb, offset ) > 0 )
|
|
&& ( tvb_get_guint8( tvb, offset ) != RTCP_SDES_END ) ) {
|
|
/* ID, 8 bits */
|
|
sdes_type = tvb_get_guint8( tvb, offset );
|
|
proto_tree_add_item( sdes_item_tree, hf_rtcp_ssrc_type, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
|
|
/* Item length, 8 bits */
|
|
item_len = tvb_get_guint8( tvb, offset );
|
|
proto_tree_add_item( sdes_item_tree, hf_rtcp_ssrc_length, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
|
|
if ( sdes_type == RTCP_SDES_PRIV ) {
|
|
/* PRIV adds two items between the SDES length
|
|
* and value - an 8 bit length giving the
|
|
* length of a "prefix string", and the string.
|
|
*/
|
|
prefix_len = tvb_get_guint8( tvb, offset );
|
|
proto_tree_add_item( sdes_item_tree, hf_rtcp_ssrc_prefix_len, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
|
|
prefix_string = ( char * ) malloc( prefix_len + 1 );
|
|
for ( counter = 0; counter < prefix_len; counter++ )
|
|
prefix_string[ counter ] =
|
|
tvb_get_guint8( tvb, offset + counter );
|
|
/* strncpy( prefix_string, pd + offset, prefix_len ); */
|
|
prefix_string[ prefix_len ] = '\0';
|
|
proto_tree_add_string( sdes_item_tree, hf_rtcp_ssrc_prefix_string, tvb, offset, prefix_len, prefix_string );
|
|
free( prefix_string );
|
|
offset += prefix_len;
|
|
}
|
|
prefix_string = ( char * ) malloc( item_len + 1 );
|
|
for ( counter = 0; counter < item_len; counter++ )
|
|
prefix_string[ counter ] =
|
|
tvb_get_guint8( tvb, offset + counter );
|
|
/* strncpy( prefix_string, pd + offset, item_len ); */
|
|
prefix_string[ item_len] = 0;
|
|
proto_tree_add_string( sdes_item_tree, hf_rtcp_ssrc_text, tvb, offset, item_len, prefix_string );
|
|
free( prefix_string );
|
|
offset += item_len;
|
|
}
|
|
|
|
/* Set the length of the items subtree. */
|
|
proto_item_set_len(ti, offset - items_start_offset);
|
|
|
|
/* 32 bits = 4 bytes, so.....
|
|
* If offset % 4 != 0, we divide offset by 4, add one and then
|
|
* multiply by 4 again to reach the boundary
|
|
*/
|
|
if ( offset % 4 != 0 )
|
|
offset = ((offset / 4) + 1 ) * 4;
|
|
|
|
/* Set the length of this chunk. */
|
|
proto_item_set_len(sdes_item, offset - start_offset);
|
|
|
|
chunk++;
|
|
}
|
|
}
|
|
|
|
static int
|
|
dissect_rtcp_rr( tvbuff_t *tvb, int offset, proto_tree *tree,
|
|
unsigned int count )
|
|
{
|
|
unsigned int counter = 1;
|
|
proto_tree *ssrc_tree = (proto_tree*) NULL;
|
|
proto_tree *ssrc_sub_tree = (proto_tree*) NULL;
|
|
proto_tree *high_sec_tree = (proto_tree*) NULL;
|
|
proto_item *ti = (proto_item*) NULL;
|
|
guint8 rr_flt;
|
|
unsigned int cum_nr = 0;
|
|
|
|
while ( counter <= count ) {
|
|
/* Create a new subtree for a length of 24 bytes */
|
|
ti = proto_tree_add_text(tree, tvb, offset, 24,
|
|
"Source %u", counter );
|
|
ssrc_tree = proto_item_add_subtree( ti, ett_ssrc );
|
|
|
|
/* SSRC_n source identifier, 32 bits */
|
|
proto_tree_add_uint( ssrc_tree, hf_rtcp_ssrc_source, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
ti = proto_tree_add_text(ssrc_tree, tvb, offset, 20, "SSRC contents" );
|
|
ssrc_sub_tree = proto_item_add_subtree( ti, ett_ssrc_item );
|
|
|
|
/* Fraction lost, 8bits */
|
|
rr_flt = tvb_get_guint8( tvb, offset );
|
|
proto_tree_add_uint_format( ssrc_sub_tree, hf_rtcp_ssrc_fraction, tvb,
|
|
offset, 1, rr_flt, "Fraction lost: %u / 256", rr_flt );
|
|
offset++;
|
|
|
|
/* Cumulative number of packets lost, 24 bits */
|
|
cum_nr = tvb_get_ntohl( tvb, offset ) >> 8;
|
|
proto_tree_add_uint( ssrc_sub_tree, hf_rtcp_ssrc_cum_nr, tvb,
|
|
offset, 3, cum_nr );
|
|
offset += 3;
|
|
|
|
/* Extended highest sequence nr received, 32 bits
|
|
* Just for the sake of it, let's add another subtree
|
|
* because this might be a little clearer
|
|
*/
|
|
ti = proto_tree_add_uint( ssrc_tree, hf_rtcp_ssrc_ext_high_seq,
|
|
tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
high_sec_tree = proto_item_add_subtree( ti, ett_ssrc_ext_high );
|
|
/* Sequence number cycles */
|
|
proto_tree_add_uint( high_sec_tree, hf_rtcp_ssrc_high_cycles,
|
|
tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
/* highest sequence number received */
|
|
proto_tree_add_uint( high_sec_tree, hf_rtcp_ssrc_high_seq,
|
|
tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
|
|
/* Interarrival jitter */
|
|
proto_tree_add_uint( ssrc_tree, hf_rtcp_ssrc_jitter, tvb,
|
|
offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
/* Last SR timestamp */
|
|
proto_tree_add_uint( ssrc_tree, hf_rtcp_ssrc_lsr, tvb,
|
|
offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
/* Delay since last SR timestamp */
|
|
proto_tree_add_uint( ssrc_tree, hf_rtcp_ssrc_dlsr, tvb,
|
|
offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
counter++;
|
|
}
|
|
|
|
return offset;
|
|
}
|
|
|
|
static int
|
|
dissect_rtcp_sr( tvbuff_t *tvb, int offset, proto_tree *tree,
|
|
unsigned int count )
|
|
{
|
|
#if 0
|
|
gchar buff[ NTP_TS_SIZE ];
|
|
char* ptime = tvb_get_ptr( tvb, offset, 8 );
|
|
|
|
/* Retreive the NTP timestamp. Using the NTP dissector for this */
|
|
ntp_fmt_ts( ptime, buff );
|
|
proto_tree_add_string_format( tree, hf_rtcp_ntp, tvb, offset, 8, ( const char* ) &buff, "NTP timestamp: %s", &buff );
|
|
free( ptime ); ??????????????????????????????????????????????????????????????????
|
|
offset += 8;
|
|
#else
|
|
/*
|
|
* XXX - RFC 1889 says this is an NTP timestamp, but that appears
|
|
* not to be the case.
|
|
*/
|
|
proto_tree_add_text(tree, tvb, offset, 4, "Timestamp, MSW: %u",
|
|
tvb_get_ntohl(tvb, offset));
|
|
offset += 4;
|
|
proto_tree_add_text(tree, tvb, offset, 4, "Timestamp, LSW: %u",
|
|
tvb_get_ntohl(tvb, offset));
|
|
offset += 4;
|
|
#endif
|
|
/* RTP timestamp, 32 bits */
|
|
proto_tree_add_uint( tree, hf_rtcp_rtp_timestamp, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
/* Sender's packet count, 32 bits */
|
|
proto_tree_add_uint( tree, hf_rtcp_sender_pkt_cnt, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
/* Sender's octet count, 32 bits */
|
|
proto_tree_add_uint( tree, hf_rtcp_sender_oct_cnt, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
/* The rest of the packet is equal to the RR packet */
|
|
if ( count != 0 )
|
|
offset = dissect_rtcp_rr( tvb, offset, tree, count );
|
|
|
|
return offset;
|
|
}
|
|
|
|
static void
|
|
dissect_rtcp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
|
|
{
|
|
proto_item *ti = NULL;
|
|
proto_tree *rtcp_tree = NULL;
|
|
unsigned int temp_byte = 0;
|
|
unsigned int padding_set = 0;
|
|
unsigned int elem_count = 0;
|
|
unsigned int packet_type = 0;
|
|
unsigned int offset = 0;
|
|
guint16 packet_length = 0;
|
|
|
|
if ( check_col( pinfo->cinfo, COL_PROTOCOL ) ) {
|
|
col_set_str( pinfo->cinfo, COL_PROTOCOL, "RTCP" );
|
|
}
|
|
|
|
if ( check_col( pinfo->cinfo, COL_INFO) ) {
|
|
/* The second octet contains the packet type */
|
|
/* switch ( pd[ offset + 1 ] ) { */
|
|
switch ( tvb_get_guint8( tvb, 1 ) ) {
|
|
case RTCP_SR:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Sender Report");
|
|
break;
|
|
case RTCP_RR:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Receiver Report");
|
|
break;
|
|
case RTCP_SDES:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Source Description");
|
|
break;
|
|
case RTCP_BYE:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Goodbye");
|
|
break;
|
|
case RTCP_APP:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Application defined");
|
|
break;
|
|
case RTCP_FIR:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Full Intra-frame Request (H.261)");
|
|
break;
|
|
case RTCP_NACK:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Negative Acknowledgement (H.261)");
|
|
break;
|
|
default:
|
|
col_set_str( pinfo->cinfo, COL_INFO, "Unknown packet type");
|
|
break;
|
|
}
|
|
}
|
|
|
|
if ( tree ) {
|
|
|
|
/*
|
|
* Check if there are at least 4 bytes left in the frame,
|
|
* the last 16 bits of those is the length of the current
|
|
* RTCP message. The last compound message contains padding,
|
|
* that enables us to break from the while loop.
|
|
*/
|
|
while ( tvb_bytes_exist( tvb, offset, 4) ) {
|
|
/*
|
|
* First retreive the packet_type
|
|
*/
|
|
packet_type = tvb_get_guint8( tvb, offset + 1 );
|
|
|
|
/*
|
|
* Check if it's a valid type
|
|
*/
|
|
if ( ( packet_type < 192 ) || ( packet_type > 204 ) )
|
|
break;
|
|
|
|
/*
|
|
* get the packet-length for the complete RTCP packet
|
|
*/
|
|
packet_length = ( tvb_get_ntohs( tvb, offset + 2 ) + 1 ) * 4;
|
|
|
|
ti = proto_tree_add_item(tree, proto_rtcp, tvb, offset, packet_length, FALSE );
|
|
rtcp_tree = proto_item_add_subtree( ti, ett_rtcp );
|
|
|
|
temp_byte = tvb_get_guint8( tvb, offset );
|
|
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_version, tvb,
|
|
offset, 1, RTCP_VERSION( temp_byte ) );
|
|
padding_set = RTCP_PADDING( temp_byte );
|
|
proto_tree_add_boolean( rtcp_tree, hf_rtcp_padding, tvb,
|
|
offset, 1, padding_set );
|
|
elem_count = RTCP_COUNT( temp_byte );
|
|
|
|
switch ( packet_type ) {
|
|
case RTCP_SR:
|
|
case RTCP_RR:
|
|
/* Receiver report count, 5 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_rc, tvb, offset, 1, elem_count );
|
|
offset++;
|
|
/* Packet type, 8 bits */
|
|
proto_tree_add_item( rtcp_tree, hf_rtcp_pt, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
/* Packet length in 32 bit words MINUS one, 16 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_length, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
/* Sender Synchronization source, 32 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_ssrc_sender, tvb, offset, 4, tvb_get_ntohl( tvb, offset ) );
|
|
offset += 4;
|
|
|
|
if ( packet_type == RTCP_SR ) offset = dissect_rtcp_sr( tvb, offset, rtcp_tree, elem_count );
|
|
else offset = dissect_rtcp_rr( tvb, offset, rtcp_tree, elem_count );
|
|
break;
|
|
case RTCP_SDES:
|
|
/* Source count, 5 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_sc, tvb, offset, 1, elem_count );
|
|
offset++;
|
|
/* Packet type, 8 bits */
|
|
proto_tree_add_item( rtcp_tree, hf_rtcp_pt, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
/* Packet length in 32 bit words MINUS one, 16 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_length, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
dissect_rtcp_sdes( tvb, offset, rtcp_tree, elem_count );
|
|
offset += packet_length - 4;
|
|
break;
|
|
case RTCP_BYE:
|
|
/* Source count, 5 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_sc, tvb, offset, 1, elem_count );
|
|
offset++;
|
|
/* Packet type, 8 bits */
|
|
proto_tree_add_item( rtcp_tree, hf_rtcp_pt, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
/* Packet length in 32 bit words MINUS one, 16 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_length, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
offset = dissect_rtcp_bye( tvb, offset, rtcp_tree, elem_count );
|
|
break;
|
|
case RTCP_APP:
|
|
/* Subtype, 5 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_subtype, tvb, offset, 1, elem_count );
|
|
offset++;
|
|
/* Packet type, 8 bits */
|
|
proto_tree_add_item( rtcp_tree, hf_rtcp_pt, tvb, offset, 1, FALSE );
|
|
offset++;
|
|
/* Packet length in 32 bit words MINUS one, 16 bits */
|
|
proto_tree_add_uint( rtcp_tree, hf_rtcp_length, tvb, offset, 2, tvb_get_ntohs( tvb, offset ) );
|
|
offset += 2;
|
|
offset = dissect_rtcp_app( tvb, offset,
|
|
rtcp_tree, padding_set,
|
|
packet_length - 4 );
|
|
break;
|
|
case RTCP_FIR:
|
|
offset = dissect_rtcp_fir( tvb, offset, rtcp_tree );
|
|
break;
|
|
case RTCP_NACK:
|
|
offset = dissect_rtcp_nack( tvb, offset, rtcp_tree );
|
|
break;
|
|
default:
|
|
/*
|
|
* To prevent endless loops in case of an unknown message type
|
|
* increase offset. Some time the while will end :-)
|
|
*/
|
|
offset++;
|
|
break;
|
|
}
|
|
}
|
|
/* If the padding bit is set, the last octet of the
|
|
* packet contains the length of the padding
|
|
* We only have to check for this at the end of the LAST RTCP message
|
|
*/
|
|
if ( padding_set ) {
|
|
/* If everything went according to plan offset should now point to the
|
|
* first octet of the padding
|
|
*/
|
|
proto_tree_add_item( rtcp_tree, hf_rtcp_padding_data, tvb, offset, tvb_length_remaining( tvb, offset) - 1, FALSE );
|
|
offset += tvb_length_remaining( tvb, offset) - 1;
|
|
proto_tree_add_item( rtcp_tree, hf_rtcp_padding_count, tvb, offset, 1, FALSE );
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
proto_register_rtcp(void)
|
|
{
|
|
static hf_register_info hf[] =
|
|
{
|
|
{
|
|
&hf_rtcp_version,
|
|
{
|
|
"Version",
|
|
"rtcp.version",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
VALS(rtcp_version_vals),
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_padding,
|
|
{
|
|
"Padding",
|
|
"rtcp.padding",
|
|
FT_BOOLEAN,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_rc,
|
|
{
|
|
"Reception report count",
|
|
"rtcp.rc",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_sc,
|
|
{
|
|
"Source count",
|
|
"rtcp.sc",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_pt,
|
|
{
|
|
"Packet type",
|
|
"rtcp.pt",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
VALS( rtcp_packet_type_vals ),
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_length,
|
|
{
|
|
"Length",
|
|
"rtcp.length",
|
|
FT_UINT16,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_sender,
|
|
{
|
|
"Sender SSRC",
|
|
"rtcp.senderssrc",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ntp,
|
|
{
|
|
"NTP timestamp",
|
|
"rtcp.timestamp.ntp",
|
|
FT_STRING,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_rtp_timestamp,
|
|
{
|
|
"RTP timestamp",
|
|
"rtcp.timestamp.rtp",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_sender_pkt_cnt,
|
|
{
|
|
"Sender's packet count",
|
|
"rtcp.sender.packetcount",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_sender_oct_cnt,
|
|
{
|
|
"Sender's octet count",
|
|
"rtcp.sender.octetcount",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_source,
|
|
{
|
|
"Identifier",
|
|
"rtcp.ssrc.identifier",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_fraction,
|
|
{
|
|
"Fraction lost",
|
|
"rtcp.ssrc.fraction",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_cum_nr,
|
|
{
|
|
"Cumulative number of packets lost",
|
|
"rtcp.ssrc.cum_nr",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_ext_high_seq,
|
|
{
|
|
"Extended highest sequence number received",
|
|
"rtcp.ssrc.ext_high",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_high_seq,
|
|
{
|
|
"Highest sequence number received",
|
|
"rtcp.ssrc.high_seq",
|
|
FT_UINT16,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_high_cycles,
|
|
{
|
|
"Sequence number cycles count",
|
|
"rtcp.ssrc.high_cycles",
|
|
FT_UINT16,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_jitter,
|
|
{
|
|
"Interarrival jitter",
|
|
"rtcp.ssrc.jitter",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_lsr,
|
|
{
|
|
"Last SR timestamp",
|
|
"rtcp.ssrc.lsr",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_dlsr,
|
|
{
|
|
"Delay since last SR timestamp",
|
|
"rtcp.ssrc.dlsr",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_csrc,
|
|
{
|
|
"SSRC / CSRC identifier",
|
|
"rtcp.sdes.ssrc_csrc",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_type,
|
|
{
|
|
"Type",
|
|
"rtcp.sdes.type",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
VALS( rtcp_sdes_type_vals ),
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_length,
|
|
{
|
|
"Length",
|
|
"rtcp.sdes.length",
|
|
FT_UINT32,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_text,
|
|
{
|
|
"Text",
|
|
"rtcp.sdes.text",
|
|
FT_STRING,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_prefix_len,
|
|
{
|
|
"Prefix length",
|
|
"rtcp.sdes.prefix.length",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_ssrc_prefix_string,
|
|
{
|
|
"Prefix string",
|
|
"rtcp.sdes.prefix.string",
|
|
FT_STRING,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_subtype,
|
|
{
|
|
"Subtype",
|
|
"rtcp.app.subtype",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_name_ascii,
|
|
{
|
|
"Name (ASCII)",
|
|
"rtcp.app.name",
|
|
FT_STRING,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_app_data,
|
|
{
|
|
"Application specific data",
|
|
"rtcp.app.data",
|
|
FT_BYTES,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_fsn,
|
|
{
|
|
"First sequence number",
|
|
"rtcp.nack.fsn",
|
|
FT_UINT16,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_blp,
|
|
{
|
|
"Bitmask of following lost packets",
|
|
"rtcp.nack.blp",
|
|
FT_UINT16,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_padding_count,
|
|
{
|
|
"Padding count",
|
|
"rtcp.padding.count",
|
|
FT_UINT8,
|
|
BASE_DEC,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
{
|
|
&hf_rtcp_padding_data,
|
|
{
|
|
"Padding data",
|
|
"rtcp.padding.data",
|
|
FT_BYTES,
|
|
BASE_NONE,
|
|
NULL,
|
|
0x0,
|
|
"", HFILL
|
|
}
|
|
},
|
|
};
|
|
|
|
static gint *ett[] =
|
|
{
|
|
&ett_rtcp,
|
|
&ett_ssrc,
|
|
&ett_ssrc_item,
|
|
&ett_ssrc_ext_high,
|
|
&ett_sdes,
|
|
&ett_sdes_item,
|
|
};
|
|
|
|
|
|
proto_rtcp = proto_register_protocol("Real-time Transport Control Protocol",
|
|
"RTCP", "rtcp");
|
|
proto_register_field_array(proto_rtcp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
|
|
register_dissector("rtcp", dissect_rtcp, proto_rtcp);
|
|
|
|
#if 0
|
|
register_init_routine( &rtcp_init );
|
|
#endif
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_rtcp(void)
|
|
{
|
|
dissector_handle_t rtcp_handle;
|
|
|
|
/*
|
|
* Register this dissector as one that can be selected by a
|
|
* UDP port number.
|
|
*/
|
|
rtcp_handle = find_dissector("rtcp");
|
|
dissector_add_handle("udp.port", rtcp_handle);
|
|
}
|