--- /dev/null
+/* packet-h223.c
+ * Routines for H.223 packet dissection
+ * Copyright (c) 2004-5 MX Telecom Ltd <richardv@mxtelecom.com>
+ *
+ * $Id$
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+
+#include <gmodule.h>
+#include <glib.h>
+#include <epan/emem.h>
+#include <epan/bitswap.h>
+#include <epan/circuit.h>
+#include <epan/conversation.h>
+#include <epan/packet.h>
+#include <epan/stream.h>
+#include <epan/reassemble.h>
+#include <epan/iax2_codec_type.h>
+#include <epan/dissectors/packet-frame.h>
+#include <epan/dissectors/packet-h245.h>
+
+#include "packet-h223.h"
+#include "golay.h"
+
+#include <string.h>
+
+#define PROTO_TAG_H223 "H223"
+
+/* Ethereal ID of the H.223 protocol */
+static int proto_h223 = -1;
+
+/* The following hf_* variables are used to hold the ethereal IDs of
+ * our header fields; they are filled out when we call
+ * proto_register_field_array() in proto_register_h223()
+ */
+static int hf_h223_non_h223_data = -1;
+static int hf_h223_mux_stuffing_pdu = -1;
+static int hf_h223_mux_pdu = -1;
+static int hf_h223_mux_header = -1;
+static int hf_h223_mux_rawhdr = -1;
+static int hf_h223_mux_correctedhdr = -1;
+static int hf_h223_mux_mc = -1;
+static int hf_h223_mux_mpl = -1;
+static int hf_h223_mux_deact = -1;
+static int hf_h223_mux_vc = -1;
+static int hf_h223_mux_extra = -1;
+static int hf_h223_mux_hdlc2 = -1;
+static int hf_h223_mux_fragments = -1;
+static int hf_h223_mux_fragment = -1;
+static int hf_h223_mux_fragment_overlap = -1;
+static int hf_h223_mux_fragment_overlap_conflict = -1;
+static int hf_h223_mux_fragment_multiple_tails = -1;
+static int hf_h223_mux_fragment_too_long_fragment = -1;
+static int hf_h223_mux_fragment_error = -1;
+static int hf_h223_mux_reassembled_in = -1;
+
+static int hf_h223_al_fragments = -1;
+static int hf_h223_al_fragment = -1;
+static int hf_h223_al_fragment_overlap = -1;
+static int hf_h223_al_fragment_overlap_conflict = -1;
+static int hf_h223_al_fragment_multiple_tails = -1;
+static int hf_h223_al_fragment_too_long_fragment = -1;
+static int hf_h223_al_fragment_error = -1;
+static int hf_h223_al_reassembled_in = -1;
+
+static int hf_h223_al1 = -1;
+static int hf_h223_al1_framed = -1;
+static int hf_h223_al2 = -1;
+static int hf_h223_al2_sequenced = -1;
+static int hf_h223_al2_seqno = -1;
+static int hf_h223_al2_crc = -1;
+static int hf_h223_al2_crc_bad = -1;
+
+static int hf_h223_al_payload = -1;
+
+/* These are the ids of the subtrees that we may be creating */
+static gint ett_h223 = -1;
+static gint ett_h223_non_h223_data = -1;
+static gint ett_h223_mux_stuffing_pdu = -1;
+static gint ett_h223_mux_pdu = -1;
+static gint ett_h223_mux_header = -1;
+static gint ett_h223_mux_deact = -1;
+static gint ett_h223_mux_vc = -1;
+static gint ett_h223_mux_extra = -1;
+static gint ett_h223_mux_fragments = -1;
+static gint ett_h223_mux_fragment = -1;
+static gint ett_h223_al_fragments = -1;
+static gint ett_h223_al_fragment = -1;
+static gint ett_h223_al1 = -1;
+static gint ett_h223_al2 = -1;
+static gint ett_h223_al_payload = -1;
+
+/* These are the handles of our subdissectors */
+static dissector_handle_t data_handle=NULL;
+static dissector_handle_t srp_handle=NULL;
+static dissector_handle_t h245dg_handle=NULL;
+
+static const fragment_items h223_mux_frag_items = {
+ &ett_h223_mux_fragment,
+ &ett_h223_mux_fragments,
+ &hf_h223_mux_fragments,
+ &hf_h223_mux_fragment,
+ &hf_h223_mux_fragment_overlap,
+ &hf_h223_mux_fragment_overlap_conflict,
+ &hf_h223_mux_fragment_multiple_tails,
+ &hf_h223_mux_fragment_too_long_fragment,
+ &hf_h223_mux_fragment_error,
+ &hf_h223_mux_reassembled_in,
+ "fragments"
+};
+
+static const fragment_items h223_al_frag_items = {
+ &ett_h223_al_fragment,
+ &ett_h223_al_fragments,
+ &hf_h223_al_fragments,
+ &hf_h223_al_fragment,
+ &hf_h223_al_fragment_overlap,
+ &hf_h223_al_fragment_overlap_conflict,
+ &hf_h223_al_fragment_multiple_tails,
+ &hf_h223_al_fragment_too_long_fragment,
+ &hf_h223_al_fragment_error,
+ &hf_h223_al_reassembled_in,
+ "fragments"
+};
+
+static guint32 pdu_offset; // offset of the last pdu to start being dissected in the last packet to start being dissected
+
+/***************************************************************************
+ *
+ * virtual circuit number handling
+ *
+ * we have to be able to manage more than one H.223 call at a time,
+ * so have a hash which maps {call,vc} to an integer.
+ */
+
+typedef struct _h223_call_info h223_call_info;
+
+typedef struct {
+ const h223_call_info* call; /* h223 call */
+ guint32 vc; /* child circuit */
+} circuit_chain_key;
+
+static GHashTable *circuit_chain_hashtable = NULL;
+static guint circuit_chain_count = 1;
+
+/* Hash Functions */
+static gint circuit_chain_equal(gconstpointer v, gconstpointer w)
+{
+ const circuit_chain_key *v1 = (const circuit_chain_key *)v;
+ const circuit_chain_key *v2 = (const circuit_chain_key *)w;
+ gint result;
+ result = ( v1->call == v2->call &&
+ v1->vc == v2 -> vc );
+ return result;;
+}
+
+static guint circuit_chain_hash (gconstpointer v)
+{
+ const circuit_chain_key *key = (const circuit_chain_key *)v;
+ guint hash_val = ((guint32)(key->call))^(((guint32)key->vc) << 16);
+ return hash_val;
+}
+
+static guint32 circuit_chain_lookup(const h223_call_info* call_info,
+ guint32 child_vc)
+{
+ circuit_chain_key key, *new_key;
+ guint32 circuit_id;
+ key.call = call_info;
+ key.vc = child_vc;
+ circuit_id = GPOINTER_TO_UINT(g_hash_table_lookup( circuit_chain_hashtable, &key ));
+ if( circuit_id == 0 ) {
+ new_key = se_alloc(sizeof(circuit_chain_key));
+ *new_key = key;
+ circuit_id = ++circuit_chain_count;
+ g_hash_table_insert(circuit_chain_hashtable, new_key, GUINT_TO_POINTER(circuit_id));
+ }
+ return circuit_id;
+}
+
+static void circuit_chain_init(void)
+{
+ if (circuit_chain_hashtable)
+ g_hash_table_destroy(circuit_chain_hashtable);
+ circuit_chain_hashtable = g_hash_table_new(circuit_chain_hash, circuit_chain_equal);
+ circuit_chain_count = 1;
+}
+
+
+/***************************************************************************
+ *
+ * Call information management
+ *
+ */
+
+/* we keep information on each call in an h223_call_info structure
+ *
+ * We attach the h223_call_info structures to individual calls with
+ * circuit_add_proto_data().
+*/
+
+typedef struct _h223_mux_element_listitem h223_mux_element_listitem;
+struct _h223_mux_element_listitem {
+ h223_mux_element *me;
+ guint32 first_frame;
+ guint32 pdu_offset;
+ h223_mux_element_listitem *next;
+};
+
+/* we have this information for each stream */
+typedef struct {
+ gboolean current_pdu_header_parsed;
+
+ guint32 current_pdu_minlen;
+ guint32 current_pdu_read;
+
+ guint32 header_buf;
+ guint32 tail_buf;
+
+ gboolean first_pdu;
+
+ h223_mux_element_listitem* mux_table[16];
+} h223_call_direction_data;
+
+
+struct _h223_call_info {
+ /* H.223 specifies that the least-significant bit is transmitted first;
+ however this is at odds with IAX which transmits the MSB first, so
+ in general, all of our bytes are reversed. */
+ gboolean bitswapped;
+
+ /* H.223 level: 0 for standard H223, 1, 2 or 3 for the enhanced protocols
+ specified in the annexes
+ */
+ int h223_level;
+
+ /* for H.223 streams over TCP (as opposed to IAX), this
+ stores the source address and port of the first packet spotted,
+ so that we can differentiate directions.
+ */
+ address srcaddress;
+ guint32 srcport;
+
+ h223_call_direction_data direction_data[2];
+};
+
+typedef struct _h223_lc_params_listitem h223_lc_params_listitem;
+struct _h223_lc_params_listitem
+{
+ h223_lc_params *lc_params;
+ guint32 first_frame;
+ guint32 last_frame;
+ h223_lc_params_listitem *next;
+};
+
+typedef struct {
+ h223_lc_params_listitem *lc_params[2];
+ h223_call_info *call_info;
+} h223_vc_info;
+
+static void add_h223_mux_element(h223_call_direction_data *direct, guint8 mc, h223_mux_element *me, guint32 framenum)
+{
+ h223_mux_element_listitem *li = se_alloc(sizeof(h223_mux_element_listitem));
+ h223_mux_element_listitem **old_li_ptr = &(direct->mux_table[mc]);
+ h223_mux_element_listitem *old_li = *old_li_ptr;
+ if( !old_li ) {
+ direct->mux_table[mc] = li;
+ } else {
+ while( old_li->next ) {
+ old_li_ptr = &(old_li->next);
+ old_li = *old_li_ptr;
+ }
+ if( framenum < old_li->first_frame || (framenum == old_li->first_frame && pdu_offset < old_li->pdu_offset) )
+ return;
+ else if ( framenum == old_li->first_frame && pdu_offset == old_li->pdu_offset )
+ *old_li_ptr = li; // replace the tail of the list with the new item, since
+ // a single h223 pdu has just set the same MC twice..
+ else
+ old_li->next = li;
+ }
+ li->first_frame = framenum;
+ li->pdu_offset = pdu_offset;
+ li->next = 0;
+ li->me = me;
+}
+
+static h223_mux_element* find_h223_mux_element(h223_call_direction_data* direct, guint8 mc, guint32 framenum)
+{
+ h223_mux_element_listitem* li = direct->mux_table[mc];
+ while( li && li->next && li->next->first_frame < framenum )
+ li = li->next;
+ while( li && li->next && li->next->first_frame == framenum && li->next->pdu_offset < pdu_offset )
+ li = li->next;
+ if( li ) {
+ return li->me;
+ } else {
+ return NULL;
+ }
+}
+
+static void add_h223_lc_params(h223_vc_info* vc_info, int direction, h223_lc_params *lc_params, guint32 framenum )
+{
+ h223_lc_params_listitem *li = se_alloc(sizeof(h223_lc_params_listitem));
+ h223_lc_params_listitem **old_li_ptr = &(vc_info->lc_params[direction]);
+ h223_lc_params_listitem *old_li = *old_li_ptr;
+ if( !old_li ) {
+ vc_info->lc_params[direction] = li;
+ } else {
+ while( old_li->next ) {
+ old_li_ptr = &(old_li->next);
+ old_li = *old_li_ptr;
+ }
+ if( framenum < old_li->first_frame )
+ return;
+ else if( framenum == old_li->first_frame )
+ *old_li_ptr = li;
+ else {
+ old_li->next = li;
+ old_li->last_frame = framenum - 1;
+ }
+ }
+ li->first_frame = framenum;
+ li->last_frame = 0;
+ li->next = 0;
+ li->lc_params = lc_params;
+}
+
+static h223_lc_params* find_h223_lc_params(h223_vc_info* vc_info, int direction, guint32 framenum)
+{
+ h223_lc_params_listitem* li = vc_info->lc_params[direction];
+ while( li && li->next && li->next->first_frame <= framenum )
+ li = li->next;
+ if( li )
+ return li->lc_params;
+ else
+ return NULL;
+}
+
+static void init_direction_data(h223_call_direction_data *direct)
+{
+ int i;
+ h223_mux_element *mc0_element;
+ direct -> first_pdu = TRUE;
+
+ for ( i = 0; i < 16; ++i )
+ direct->mux_table[i] = NULL;
+
+ /* set up MC 0 to contain just VC 0 */
+ mc0_element = se_alloc(sizeof(h223_mux_element));
+ add_h223_mux_element( direct, 0, mc0_element, 0 );
+ mc0_element->sublist = NULL;
+ mc0_element->vc = 0;
+ mc0_element->repeat_count = 0; /* until closing flag */
+ mc0_element->next = NULL;
+}
+
+static h223_vc_info* h223_vc_info_new( h223_call_info* call_info )
+{
+ h223_vc_info *vc_info = se_alloc(sizeof(h223_vc_info));
+ vc_info->lc_params[0] = vc_info->lc_params[1] = NULL;
+ vc_info->call_info = call_info;
+ return vc_info;
+}
+
+static void init_logical_channel( packet_info* pinfo, h223_call_info* call_info, int vc, int direction, h223_lc_params* params )
+{
+ guint32 circuit_id = circuit_chain_lookup(call_info, vc);
+ circuit_t *subcircuit;
+ h223_vc_info *vc_info;
+ subcircuit = find_circuit( CT_H223, circuit_id, pinfo->fd->num );
+
+ if( subcircuit == NULL ) {
+ subcircuit = circuit_new( CT_H223, circuit_id, pinfo->fd->num );
+ vc_info = h223_vc_info_new( call_info );
+ circuit_add_proto_data( subcircuit, proto_h223, vc_info );
+ } else {
+ vc_info = circuit_get_proto_data( subcircuit, proto_h223 );
+ }
+ add_h223_lc_params( vc_info, direction, params, pinfo->fd->num );
+}
+
+static void init_control_channels( packet_info* pinfo, h223_call_info* call_info )
+{
+ h223_lc_params *vc0_params = se_alloc(sizeof(h223_lc_params));
+ vc0_params->al_type = al1Framed;
+ vc0_params->al_params = NULL;
+ vc0_params->segmentable = TRUE;
+ vc0_params->subdissector = srp_handle;
+ init_logical_channel( pinfo, call_info, 0, P2P_DIR_SENT, vc0_params );
+ init_logical_channel( pinfo, call_info, 0, P2P_DIR_RECV, vc0_params );
+}
+
+static h223_call_info *find_or_create_call_info ( packet_info * pinfo )
+{
+ circuit_t *circ;
+ conversation_t *conv = NULL;
+ h223_call_info *data;
+
+ // look for a circuit (eg, IAX call) first
+ circ = find_circuit( pinfo->ctype, pinfo->circuit_id, pinfo->fd->num );
+ if( circ == NULL ) {
+ // assume we're running atop TCP; use the converstion support
+ conv = find_conversation( pinfo->fd->num,
+ &pinfo->src,&pinfo->dst,
+ pinfo->ptype,
+ pinfo->srcport,pinfo->destport, 0 );
+ if( conv == NULL ) {
+ conv = conversation_new( pinfo->fd->num,
+ &pinfo->src,&pinfo->dst,
+ pinfo->ptype,
+ pinfo->srcport,pinfo->destport, 0 );
+ }
+
+ }
+
+ if( circ )
+ data = (h223_call_info *)circuit_get_proto_data(circ, proto_h223);
+ else
+ data = (h223_call_info *)conversation_get_proto_data(conv, proto_h223);
+
+ if( data == NULL ) {
+ data = se_alloc(sizeof(h223_call_info));
+
+ if( circ ) {
+ circuit_add_proto_data(circ, proto_h223, data);
+
+ /* circuit-switched H.223 conversations are bitswapped */
+ data -> bitswapped = TRUE;
+ } else {
+ conversation_add_proto_data(conv, proto_h223, data);
+ /* add the source details so we can distinguish directions
+ * in future */
+ COPY_ADDRESS(&(data -> srcaddress), &(pinfo->src));
+ data -> srcport = pinfo->srcport;
+
+ /* packet-switched H.223 conversations are NOT bitswapped */
+ data -> bitswapped = FALSE;
+ }
+
+ /* initialise the call info */
+ init_direction_data(&data -> direction_data[0]);
+ init_direction_data(&data -> direction_data[1]);
+
+ /* FIXME shouldn't this be figured out dynamically? */
+ data -> h223_level = 2;
+
+ init_control_channels( pinfo, data );
+ }
+
+ /* work out what direction we're really going in */
+ if( circ ) {
+ if( pinfo->p2p_dir < 0 || pinfo->p2p_dir > 1)
+ pinfo->p2p_dir = P2P_DIR_SENT;
+ } else {
+ if( ADDRESSES_EQUAL( &(pinfo->src), &(data->srcaddress))
+ && pinfo->srcport == data->srcport )
+ pinfo->p2p_dir = P2P_DIR_SENT;
+ else
+ pinfo->p2p_dir = P2P_DIR_RECV;
+ }
+
+ return data;
+}
+
+void h223_set_mc( packet_info* pinfo, guint8 mc, h223_mux_element* me )
+{
+ circuit_t *circ = find_circuit( pinfo->ctype, pinfo->circuit_id, pinfo->fd->num );
+ h223_vc_info* vc_info;
+ g_assert( circ );
+ vc_info = circuit_get_proto_data(circ, proto_h223);
+ add_h223_mux_element( &(vc_info->call_info->direction_data[pinfo->p2p_dir]), mc, me, pinfo->fd->num );
+}
+
+void h223_add_lc( packet_info* pinfo, guint16 lc, h223_lc_params* params )
+{
+ circuit_t *circ = find_circuit( pinfo->ctype, pinfo->circuit_id, pinfo->fd->num );
+ h223_vc_info* vc_info;
+ g_assert( circ );
+ vc_info = circuit_get_proto_data(circ, proto_h223);
+ init_logical_channel( pinfo, vc_info->call_info, lc, pinfo->p2p_dir, params );
+}
+
+/************************************************************************************
+ *
+ * AL-PDU dissection
+ */
+
+const guint8 crctable[256] = {
+ 0x00, 0x91, 0xe3, 0x72, 0x07, 0x96, 0xe4, 0x75, 0x0e, 0x9f, 0xed, 0x7c, 0x09, 0x98, 0xea, 0x7b,
+ 0x1c, 0x8d, 0xff, 0x6e, 0x1b, 0x8a, 0xf8, 0x69, 0x12, 0x83, 0xf1, 0x60, 0x15, 0x84, 0xf6, 0x67,
+ 0x38, 0xa9, 0xdb, 0x4a, 0x3f, 0xae, 0xdc, 0x4d, 0x36, 0xa7, 0xd5, 0x44, 0x31, 0xa0, 0xd2, 0x43,
+ 0x24, 0xb5, 0xc7, 0x56, 0x23, 0xb2, 0xc0, 0x51, 0x2a, 0xbb, 0xc9, 0x58, 0x2d, 0xbc, 0xce, 0x5f,
+ 0x70, 0xe1, 0x93, 0x02, 0x77, 0xe6, 0x94, 0x05, 0x7e, 0xef, 0x9d, 0x0c, 0x79, 0xe8, 0x9a, 0x0b,
+ 0x6c, 0xfd, 0x8f, 0x1e, 0x6b, 0xfa, 0x88, 0x19, 0x62, 0xf3, 0x81, 0x10, 0x65, 0xf4, 0x86, 0x17,
+ 0x48, 0xd9, 0xab, 0x3a, 0x4f, 0xde, 0xac, 0x3d, 0x46, 0xd7, 0xa5, 0x34, 0x41, 0xd0, 0xa2, 0x33,
+ 0x54, 0xc5, 0xb7, 0x26, 0x53, 0xc2, 0xb0, 0x21, 0x5a, 0xcb, 0xb9, 0x28, 0x5d, 0xcc, 0xbe, 0x2f,
+ 0xe0, 0x71, 0x03, 0x92, 0xe7, 0x76, 0x04, 0x95, 0xee, 0x7f, 0x0d, 0x9c, 0xe9, 0x78, 0x0a, 0x9b,
+ 0xfc, 0x6d, 0x1f, 0x8e, 0xfb, 0x6a, 0x18, 0x89, 0xf2, 0x63, 0x11, 0x80, 0xf5, 0x64, 0x16, 0x87,
+ 0xd8, 0x49, 0x3b, 0xaa, 0xdf, 0x4e, 0x3c, 0xad, 0xd6, 0x47, 0x35, 0xa4, 0xd1, 0x40, 0x32, 0xa3,
+ 0xc4, 0x55, 0x27, 0xb6, 0xc3, 0x52, 0x20, 0xb1, 0xca, 0x5b, 0x29, 0xb8, 0xcd, 0x5c, 0x2e, 0xbf,
+ 0x90, 0x01, 0x73, 0xe2, 0x97, 0x06, 0x74, 0xe5, 0x9e, 0x0f, 0x7d, 0xec, 0x99, 0x08, 0x7a, 0xeb,
+ 0x8c, 0x1d, 0x6f, 0xfe, 0x8b, 0x1a, 0x68, 0xf9, 0x82, 0x13, 0x61, 0xf0, 0x85, 0x14, 0x66, 0xf7,
+ 0xa8, 0x39, 0x4b, 0xda, 0xaf, 0x3e, 0x4c, 0xdd, 0xa6, 0x37, 0x45, 0xd4, 0xa1, 0x30, 0x42, 0xd3,
+ 0xb4, 0x25, 0x57, 0xc6, 0xb3, 0x22, 0x50, 0xc1, 0xba, 0x2b, 0x59, 0xc8, 0xbd, 0x2c, 0x5e, 0xcf };
+
+static guint8 h223_al2_crc8bit( tvbuff_t *tvb ) {
+ guint32 len = tvb_reported_length(tvb) - 1;
+ const guint8* data = tvb_get_ptr( tvb, 0, len );
+ unsigned char crc = 0;
+ guint32 pos = 0;
+ while ( len-- )
+ crc = crctable[crc^data[pos++]];
+ return crc;
+}
+
+static void dissect_mux_al_pdu( tvbuff_t *tvb,
+ packet_info *pinfo,
+ proto_tree *vc_tree,
+// circuit_t* vc_circuit,
+ h223_lc_params* lc_params )
+{
+ proto_tree *al_tree = NULL;
+ proto_item *al_item;
+ proto_tree *al_subtree;
+ proto_item *al_subitem = NULL;
+ tvbuff_t *next_tvb = NULL;
+ dissector_handle_t subdissector = lc_params->subdissector;
+ guint32 len = tvb_reported_length(tvb);
+ gboolean all_done = FALSE;
+
+ guint8 calc_checksum;
+ guint8 real_checksum;
+ gboolean al2_sequenced;
+
+ switch( lc_params->al_type ) {
+ case al1Framed:
+ case al1NotFramed:
+ al_item = proto_tree_add_none_format(vc_tree, hf_h223_al1, tvb, 0, -1, "H.223 AL1 (%sframed)",
+ (lc_params->al_type==al1Framed)?"":"not ");
+ al_tree = proto_item_add_subtree (al_item, ett_h223_al1);
+ if(lc_params->al_type == al1Framed)
+ proto_tree_add_boolean_hidden(al_tree, hf_h223_al1_framed, tvb, 0, 1, TRUE );
+ next_tvb = tvb;
+ break;
+ case al2WithoutSequenceNumbers:
+ case al2WithSequenceNumbers:
+ if( lc_params->al_type == al2WithoutSequenceNumbers ) {
+ next_tvb = tvb_new_subset( tvb, 0, len-1, len-1 );
+ al2_sequenced = FALSE;
+ } else {
+ next_tvb = tvb_new_subset( tvb, 1, len-2, len-2 );
+ al2_sequenced = TRUE;
+ }
+
+ al_item = proto_tree_add_none_format(vc_tree, hf_h223_al2, tvb, 0, -1, "H223 AL2 (with%s sequence numbers)",
+ al2_sequenced?"":"out" );
+ al_tree = proto_item_add_subtree (al_item, ett_h223_al2);
+
+ if( al2_sequenced ) {
+ proto_tree_add_boolean_hidden(al_tree, hf_h223_al2_sequenced, tvb, 0, 1, TRUE );
+ proto_tree_add_uint_format(al_tree, hf_h223_al2_seqno, tvb, 0, 1, tvb_get_guint8( tvb, 0 ),
+ "Sequence number: %u", tvb_get_guint8( tvb, 0 ) );
+ }
+
+ calc_checksum = h223_al2_crc8bit(tvb);
+ real_checksum = tvb_get_guint8(tvb, len - 1);
+ if( calc_checksum == real_checksum ) {
+ al_subitem = proto_tree_add_item(al_tree, hf_h223_al_payload, next_tvb, 0, -1, FALSE);
+ proto_tree_add_uint_format(al_tree, hf_h223_al2_crc, tvb, len - 1, 1, real_checksum,
+ "CRC: 0x%02x (correct)", real_checksum );
+ } else {
+ call_dissector(data_handle, tvb, pinfo, al_tree);
+ proto_tree_add_boolean_hidden( al_tree, hf_h223_al2_crc_bad, tvb, len - 1, 1, TRUE );
+ proto_tree_add_uint_format(al_tree, hf_h223_al2_crc, tvb, len - 1, 1, real_checksum,
+ "CRC: 0x%02x (incorrect, should be 0x%02x)", real_checksum, calc_checksum );
+ all_done = TRUE;
+ }
+ break;
+ default:
+ break;
+ }
+
+ if (!subdissector)
+ subdissector = data_handle;
+
+ if(next_tvb && al_tree && !al_subitem && !all_done)
+ al_subitem = proto_tree_add_item(al_tree, hf_h223_al_payload, next_tvb, 0, -1, FALSE);
+
+ if(next_tvb && al_subitem && !all_done) {
+ al_subtree = proto_item_add_subtree(al_subitem, ett_h223_al_payload);
+ call_dissector(subdissector, next_tvb, pinfo, al_subtree);
+ } else if ( !all_done )
+ call_dissector(data_handle, tvb, pinfo, vc_tree);
+}
+
+/************************************************************************************
+ *
+ * MUX-PDU dissection
+ */
+
+
+/* dissect a fragment of a MUX-PDU which belongs to a particular VC
+ *
+ * tvb buffer containing the whole MUX-PDU
+ * offset offset within the MUX-PDU of this fragment
+ * pinfo info on the packet containing the last fragment of the MUX-PDU
+ * pkt_offset offset within that packet of the start of the final fragment of
+ * the MUX_PDU
+ * pdu_tree dissection tree for the PDU; a single item will be added (with
+ * its own subtree)
+ * vc VC for this SDU
+ * frag_len length of the MUX-SDU fragment
+ * end_of_mux_sdu true if this is a segmentable VC and this is the last
+ * fragment in an SDU
+ */
+static void dissect_mux_sdu_fragment(tvbuff_t *tvb, guint32 offset,
+ packet_info *pinfo,
+ guint32 pkt_offset,
+ proto_tree *pdu_tree,
+ h223_call_info* call_info,
+ guint16 vc, gint frag_len, gboolean end_of_mux_sdu)
+{
+ /* update the circuit details before passing to a subdissector */
+ guint32 orig_circuit = pinfo->circuit_id;
+ guint32 orig_ctype = pinfo->ctype;
+ pinfo->circuit_id=circuit_chain_lookup(call_info, vc);
+ pinfo->ctype=CT_H223;
+
+ TRY {
+ tvbuff_t *next_tvb = tvb_new_subset(tvb, offset, frag_len, frag_len);
+ circuit_t *subcircuit=find_circuit(pinfo->ctype,pinfo->circuit_id,pinfo->fd->num);
+ dissector_handle_t subdissector = NULL;
+ proto_tree *vc_tree = NULL;
+ proto_item *vc_item;
+ h223_vc_info *vc_info = NULL;
+ h223_lc_params *lc_params = NULL;
+ gboolean stuffing = ( vc == 0 && frag_len == 0 );
+
+ if(pdu_tree && !stuffing) {
+ vc_item = proto_tree_add_uint(pdu_tree, hf_h223_mux_vc, next_tvb, 0, frag_len, vc);
+ vc_tree = proto_item_add_subtree (vc_item, ett_h223_mux_vc);
+ }
+
+ if( stuffing ) {
+ next_tvb = NULL;
+ subdissector = data_handle;
+ } else if( subcircuit == NULL ) {
+ g_message( "Frame %d: no subcircuit id %d found for circuit %d id %d, vc %d", pinfo->fd->num,
+ pinfo->circuit_id, orig_ctype, orig_circuit, vc );
+ subdissector = data_handle;
+ } else {
+ vc_info = circuit_get_proto_data(subcircuit, proto_h223);
+ if( vc_info != NULL ) {
+ lc_params = find_h223_lc_params( vc_info, pinfo->p2p_dir, pinfo->fd->num );
+ }
+ if( lc_params == NULL ) {
+ subdissector = data_handle;
+ } else {
+ if( lc_params->segmentable && lc_params->al_type != al1NotFramed ) {
+ stream_t *substream;
+ stream_pdu_fragment_t *frag;
+
+ substream = find_stream_circ(subcircuit,pinfo->p2p_dir);
+ if(substream == NULL )
+ substream = stream_new_circ(subcircuit,pinfo->p2p_dir);
+ frag = stream_find_frag(substream,pinfo->fd->num,offset+pkt_offset);
+ if(frag == NULL ) {
+ frag = stream_add_frag(substream,pinfo->fd->num,offset+pkt_offset,
+ next_tvb,pinfo,!end_of_mux_sdu);
+ }
+ next_tvb = stream_process_reassembled(
+ next_tvb, 0, pinfo,
+ "Reassembled H.223 AL-PDU",
+ frag, &h223_al_frag_items,
+ NULL, vc_tree);
+ }
+ }
+ }
+
+ if(next_tvb) {
+ if(lc_params)
+ dissect_mux_al_pdu(next_tvb, pinfo, vc_tree,/* subcircuit,*/ lc_params );
+ else
+ call_dissector(subdissector,next_tvb,pinfo,vc_tree);
+ }
+ }
+
+ /* restore the original circuit details for future PDUs */
+ FINALLY {
+ pinfo->ctype=orig_ctype;
+ pinfo->circuit_id=orig_circuit;
+ }
+ ENDTRY;
+}
+
+static guint32 mux_element_sublist_size( h223_mux_element* me )
+{
+ h223_mux_element *current_me = me;
+ guint32 length = 0;
+ while ( current_me ) {
+ current_me = current_me->next;
+ if ( current_me->sublist )
+ length += current_me->repeat_count * mux_element_sublist_size( current_me->sublist );
+ else
+ length += current_me->repeat_count;
+ }
+ if ( length == 0 ) { /* should never happen, but to avoid infinite loops... */
+ DISSECTOR_ASSERT_NOT_REACHED();
+ length = 1;
+ }
+ return length;
+}
+
+static guint32 dissect_mux_payload_by_me_list( tvbuff_t *tvb, packet_info *pinfo, guint32 pkt_offset, proto_tree *pdu_tree,
+ h223_call_info* call_info, h223_mux_element* me, guint32 offset, gboolean endOfMuxSdu )
+{
+ guint32 len = tvb_reported_length(tvb);
+ guint32 frag_len;
+ guint32 sublist_len;
+ int i;
+ while ( me ) {
+ if ( me->sublist ) {
+ if ( me->repeat_count == 0 ) {
+ for(sublist_len = mux_element_sublist_size( me->sublist );
+ offset + sublist_len <= len;
+ offset = dissect_mux_payload_by_me_list( tvb, pinfo, pkt_offset, pdu_tree,
+ call_info, me->sublist, offset, endOfMuxSdu ) );
+ } else {
+ for(i = 0; i < me->repeat_count; ++i)
+ offset = dissect_mux_payload_by_me_list( tvb, pinfo, pkt_offset, pdu_tree,
+ call_info, me->sublist, offset, endOfMuxSdu );
+ }
+ } else {
+ if ( me->repeat_count == 0 )
+ frag_len = len - offset;
+ else
+ frag_len = me->repeat_count;
+ dissect_mux_sdu_fragment( tvb, offset, pinfo, pkt_offset, pdu_tree,
+ call_info, me->vc, frag_len, (offset+frag_len==len) && endOfMuxSdu);
+ offset += frag_len;
+ }
+ me = me->next;
+ }
+ return offset;
+}
+
+/* dissect the payload of a MUX-PDU */
+static void dissect_mux_payload( tvbuff_t *tvb, packet_info *pinfo, guint32 pkt_offset, proto_tree *pdu_tree,
+ h223_call_info* call_info, guint8 mc, gboolean endOfMuxSdu )
+{
+ guint32 len = tvb_reported_length(tvb);
+
+ h223_mux_element* me = find_h223_mux_element( &(call_info->direction_data[pinfo->p2p_dir]), mc, pinfo->fd->num );
+
+ if( me ) {
+ dissect_mux_payload_by_me_list( tvb, pinfo, pkt_offset, pdu_tree, call_info, me, 0, endOfMuxSdu );
+ } else {
+ /* no entry found in mux-table. ignore packet and dissect as data */
+ proto_tree *vc_tree = NULL;
+
+ if(pdu_tree) {
+ proto_item *vc_item = proto_tree_add_item(pdu_tree, hf_h223_mux_deact, tvb, 0, len, FALSE);
+ vc_tree = proto_item_add_subtree(vc_item, ett_h223_mux_deact);
+ }
+ call_dissector(data_handle,tvb,pinfo,vc_tree);
+ }
+}
+
+/* dissect a reassembled mux-pdu
+ *
+ * tvb buffer containing mux-pdu, including header and closing flag
+ * pinfo packet info for packet containing the end of the mux-pdu
+ * pkt_offset offset within that packet of the start of the last fragment
+ * h223_tree dissection tree for h223 protocol; a single item will be added
+ * (with a sub-tree)
+ * call_info h223 info structure for this h223 call
+ * pdu_no index of this pdu within the call
+ */
+static void dissect_mux_pdu( tvbuff_t *tvb, packet_info * pinfo,
+ guint32 pkt_offset,
+ proto_tree *h223_tree,
+ h223_call_info *call_info)
+{
+ guint32 offset = 0;
+ /* actual (as opposed to reported) payload len */
+ guint32 len;
+ guint32 raw_hdr = 0, correct_hdr = 0;
+ gint32 errors = 0;
+ guint16 closing_flag = 0;
+ guint8 mc = 0;
+ guint8 mpl = 0;
+ gboolean end_of_mux_sdu = FALSE;
+ tvbuff_t *pdu_tvb;
+
+ proto_item *pdu_item = NULL;
+ proto_tree *pdu_tree = NULL;
+
+ switch(call_info->h223_level) {
+ case 0: case 1:
+ raw_hdr = tvb_get_guint8(tvb,0);
+ mc = (guint8)((raw_hdr>>1) & 0xf);
+ end_of_mux_sdu = raw_hdr & 1;
+ offset++;
+ /* closing flag is one byte long for h223 level 0, two for level 1 */
+ len = mpl = tvb_length_remaining(tvb, offset)-(call_info->h223_level+1);
+
+ /* XXX should ignore pdus with incorrect HECs */
+ break;
+
+ case 2:
+ raw_hdr = tvb_get_letoh24(tvb,0);
+ errors = golay_errors(raw_hdr);
+ correct_hdr = ((errors == -1) ? raw_hdr : raw_hdr ^ (guint32)errors);
+
+ mc = (guint8)(correct_hdr & 0xf);
+ mpl = (guint8)((correct_hdr >> 4) & 0xff);
+
+ offset += 3;
+ len = tvb_length_remaining(tvb,offset)-2;
+ closing_flag = tvb_get_ntohs(tvb,offset+len);
+ end_of_mux_sdu = (closing_flag==(0xE14D ^ 0xFFFF));
+ break;
+
+ case 3:
+ /* XXX not implemented */
+ default:
+ len=0;
+ DISSECTOR_ASSERT_NOT_REACHED();
+ }
+
+
+ if( h223_tree ) {
+ if( mpl == 0 ) {
+ pdu_item = proto_tree_add_item (h223_tree, hf_h223_mux_stuffing_pdu, tvb, 0, -1, FALSE);
+ pdu_tree = proto_item_add_subtree (pdu_item, ett_h223_mux_stuffing_pdu);
+ } else {
+ pdu_item = proto_tree_add_item (h223_tree, hf_h223_mux_pdu, tvb, 0, -1, FALSE);
+ pdu_tree = proto_item_add_subtree (pdu_item, ett_h223_mux_pdu);
+ }
+ }
+
+ if( pdu_tree ) {
+ proto_item *item = proto_tree_add_item (pdu_tree, hf_h223_mux_header, tvb, 0, offset, FALSE);
+ proto_tree *hdr_tree = proto_item_add_subtree (item, ett_h223_mux_header);
+
+ switch(call_info->h223_level) {
+ case 0: case 1:
+ proto_tree_add_uint(hdr_tree,hf_h223_mux_mc,tvb,0,1,mc);
+ break;
+
+ case 2:
+ if( errors == -1 ) {
+ proto_tree_add_uint_format(hdr_tree, hf_h223_mux_rawhdr, tvb,
+ 0, 3, raw_hdr,
+ "Raw value: 0x%06x (uncorrectable errors)", raw_hdr );
+ } else if( errors == 0 ) {
+ proto_tree_add_uint_format(hdr_tree, hf_h223_mux_rawhdr, tvb,
+ 0, 3, raw_hdr,
+ "Raw value: 0x%06x (correct)", raw_hdr );
+ } else {
+ proto_tree_add_uint_format(hdr_tree, hf_h223_mux_rawhdr, tvb,
+ 0, 3, raw_hdr,
+ "Raw value: 0x%06x (errors are 0x%06x)", raw_hdr, errors );
+ }
+ item = proto_tree_add_uint(hdr_tree,hf_h223_mux_correctedhdr,tvb,0,3,
+ correct_hdr);
+ PROTO_ITEM_SET_GENERATED(item);
+
+ proto_tree_add_uint(hdr_tree,hf_h223_mux_mc,tvb,0,1,mc);
+ proto_tree_add_uint(hdr_tree,hf_h223_mux_mpl,tvb,0,2,mpl);
+ break;
+
+ case 3:
+ /* XXX not implemented */
+ default:
+ DISSECTOR_ASSERT_NOT_REACHED();
+ }
+ }
+
+ pdu_tvb = tvb_new_subset(tvb, offset, len, mpl);
+ dissect_mux_payload(pdu_tvb,pinfo,offset+pkt_offset,pdu_tree,call_info,mc,end_of_mux_sdu);
+ offset += mpl;
+
+ /* any extra data in the PDU, beyond that indictated by the mpl, is
+ dissected as data. */
+ len -= mpl;
+ if( len > 0 ) {
+ tvbuff_t *next_tvb = tvb_new_subset(tvb, offset, len, len);
+ proto_tree *vc_tree = NULL;
+
+ if( pdu_tree ) {
+ proto_item *vc_item = proto_tree_add_item(pdu_tree, hf_h223_mux_extra, next_tvb, 0, len, FALSE);
+ vc_tree = proto_item_add_subtree(vc_item, ett_h223_mux_deact);
+ }
+ call_dissector(data_handle,next_tvb,pinfo,vc_tree);
+
+ offset += len;
+ }
+
+ /* add the closing HDLC flag */
+ if( pdu_tree )
+ proto_tree_add_item(pdu_tree,hf_h223_mux_hdlc2,tvb,offset,2,FALSE);
+}
+
+
+/************************************************************************************
+ *
+ * MUX-PDU delineation and defragmentation
+ */
+
+/* attempt to parse the header of a mux pdu */
+static void attempt_mux_level0_header_parse(h223_call_direction_data *dirdata)
+{
+ /* level 0 isn't byte-aligned, so is a complete pain to implement */
+ DISSECTOR_ASSERT_NOT_REACHED();
+ dirdata = dirdata;
+}
+
+static void attempt_mux_level1_header_parse(h223_call_direction_data *dirdata)
+{
+ guint32 hdr;
+
+ if(dirdata->current_pdu_read != 2)
+ return;
+
+ hdr = dirdata->header_buf & 0xffff;
+ /* don't interpret a repeated hdlc as a header */
+ if(hdr == 0xE14D)
+ return;
+
+ /* + 1 byte of header and 2 bytes of closing HDLC */
+ dirdata -> current_pdu_minlen = (guint8)((hdr >> 12) & 0xff) + 3;
+ dirdata -> current_pdu_header_parsed = TRUE;
+}
+
+static void attempt_mux_level2_3_header_parse(h223_call_direction_data *dirdata)
+{
+ guint32 hdr;
+ gint32 errors;
+
+ if(dirdata->current_pdu_read != 3)
+ return;
+
+ /* + 3 bytes of header and 2 bytes of closing HDLC */
+ dirdata -> current_pdu_minlen = 5;
+
+ hdr = dirdata->header_buf;
+ hdr =
+ ((hdr & 0xFF0000) >> 16) |
+ (hdr & 0x00FF00) |
+ ((hdr & 0x0000FF) << 16);
+
+ errors = golay_errors(hdr);
+ if(errors != -1) {
+ hdr ^= errors;
+ dirdata -> current_pdu_minlen += ((hdr >> 4) & 0xff);
+ }
+
+ dirdata -> current_pdu_header_parsed = TRUE;
+}
+
+static void (* const attempt_mux_header_parse[])(h223_call_direction_data *dirdata) = {
+ attempt_mux_level0_header_parse,
+ attempt_mux_level1_header_parse,
+ attempt_mux_level2_3_header_parse,
+ attempt_mux_level2_3_header_parse
+};
+
+static gboolean h223_mux_check_hdlc(int h223_level, h223_call_direction_data *dirdata)
+{
+ guint32 masked;
+
+ switch(h223_level) {
+ case 0:
+ /* level 0 isn't byte-aligned, so is a complete pain to implement */
+ DISSECTOR_ASSERT_NOT_REACHED();
+ return FALSE;
+ break;
+
+ case 1:
+ masked = dirdata->tail_buf & 0xffff;
+ return masked == 0xE14D;
+
+ case 2: case 3:
+ masked = dirdata->tail_buf & 0xffff;
+ return masked == 0xE14D || masked == (0xE14D ^ 0xFFFF);
+
+ default:
+ DISSECTOR_ASSERT_NOT_REACHED();
+ return FALSE;
+ }
+}
+
+/* read a pdu (or the end of a pdu) from the tvb, and dissect it
+ *
+ * returns an offset to the next byte
+ *
+ * *pdu_found is set TRUE if a pdu was found, or FALSE if we reached the
+ * end of the tvb without completing one.
+ */
+
+static guint32 dissect_mux_pdu_fragment( tvbuff_t *tvb, guint32 start_offset, packet_info * pinfo,
+ guint32* pkt_offset,
+ proto_tree *tree,
+ proto_tree **h223_tree_p,
+ h223_call_info *call_info,
+ gboolean *pdu_found)
+{
+ proto_item *h223_item = NULL;
+ proto_tree *volatile h223_tree = *h223_tree_p;
+ tvbuff_t *volatile next_tvb;
+ volatile guint32 offset = start_offset;
+ gboolean more_frags = TRUE;
+ proto_tree *pdu_tree;
+
+ h223_call_direction_data *dirdata = &call_info -> direction_data[pinfo->p2p_dir];
+
+ dirdata -> current_pdu_read = 0;
+ dirdata -> current_pdu_minlen = 0;
+ dirdata -> current_pdu_header_parsed = FALSE;
+
+ while( more_frags && offset < tvb_reported_length( tvb )) {
+ guint8 byte = tvb_get_guint8(tvb, offset++);
+ dirdata -> current_pdu_read++;
+
+ /* read a byte into the header buf, if necessary */
+ if(dirdata -> current_pdu_read <= 4) {
+ dirdata -> header_buf <<= 8;
+ dirdata -> header_buf |= byte;
+ }
+
+ /* read the byte into the tail buf */
+ dirdata -> tail_buf <<= 8;
+ dirdata -> tail_buf |= byte;
+
+ /* if we haven't parsed the header yet, attempt to do so now */
+ if(!dirdata -> current_pdu_header_parsed)
+ /* this sets current_pdu_header parsed if current_pdu_read == 3 */
+ (attempt_mux_header_parse[call_info->h223_level])(dirdata);
+
+ if(dirdata -> current_pdu_read >= dirdata -> current_pdu_minlen) {
+ if(h223_mux_check_hdlc(call_info->h223_level,dirdata)) {
+ dirdata -> current_pdu_minlen = 0;
+ dirdata -> current_pdu_read = 0;
+ dirdata -> current_pdu_header_parsed = FALSE;
+ more_frags = FALSE;
+ }
+ }
+ }
+
+ if( more_frags ) {
+ /* offset = tvb_reported length now */
+ pinfo->desegment_offset = offset - dirdata->current_pdu_read;
+ if(dirdata->current_pdu_read > dirdata->current_pdu_minlen)
+ pinfo->desegment_len = 1;
+ else
+ pinfo->desegment_len = dirdata->current_pdu_minlen - dirdata->current_pdu_read;
+ return offset;
+ }
+
+ if(!*h223_tree_p) {
+ /* add the 'h223' tree to the main tree */
+ if (tree) {
+ h223_item = proto_tree_add_item (tree, proto_h223, tvb, 0, -1, FALSE);
+ h223_tree = proto_item_add_subtree (h223_item, ett_h223);
+ *h223_tree_p = h223_tree;
+ }
+ }
+ *pdu_found = TRUE;
+
+ /* create a tvb for the fragment */
+ next_tvb = tvb_new_subset(tvb, start_offset, offset-start_offset,
+ offset-start_offset);
+
+
+ *pkt_offset += tvb_reported_length( next_tvb );
+
+ /* the first PDU isn't real H.223 data. */
+ if( dirdata->first_pdu ) {
+ dirdata->first_pdu = FALSE;
+ pdu_tree = NULL;
+ if( h223_tree ) {
+ proto_item *pdu_item = proto_tree_add_item (h223_tree, hf_h223_non_h223_data, tvb, 0, -1, FALSE);
+ pdu_tree = proto_item_add_subtree (pdu_item, ett_h223_non_h223_data);
+ }
+ call_dissector(data_handle,tvb, pinfo, pdu_tree);
+ return offset;
+ }
+
+ /* we catch boundserrors on the pdu so that errors on an
+ * individual pdu don't screw up the whole of the rest of the
+ * stream */
+ pdu_offset = *pkt_offset - tvb_reported_length( next_tvb );
+ TRY {
+ dissect_mux_pdu( next_tvb, pinfo, *pkt_offset - tvb_reported_length( next_tvb ), h223_tree, call_info);
+ }
+
+ CATCH2(BoundsError,ReportedBoundsError) {
+ if (check_col(pinfo->cinfo, COL_INFO))
+ col_append_str(pinfo->cinfo, COL_INFO,
+ "[Malformed Packet]");
+ proto_tree_add_protocol_format(h223_tree, proto_malformed,
+ tvb, 0, 0, "[Malformed Packet: %s]", pinfo->current_proto);
+ }
+
+ ENDTRY;
+
+ return offset;
+}
+
+/************************************************************************************
+ *
+ * main dissector entry point
+ */
+
+static void dissect_h223 (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
+{
+ proto_tree *h223_tree = NULL;
+ h223_call_info *call_info = NULL;
+ guint32 offset = 0;
+
+ /* pkt_offset becomes different from offset if we reassemble a pdu:
+ *
+ * before: offset = a, pkt_offset = b
+ * offset = dissect_h223_mux_pdu_fragment(ending fragment, offset, &pkt_offset)
+ * after: offset = a + sizeof(ending frament), pkt_offset = b + sizeof(reassembled pdu)
+ *
+ * This lets us get a value "pkt_offset + offset_into_pdu" which will never decrease
+ * as we walk through a packet
+ */
+ guint32 pkt_offset = 0;
+ gboolean pdu_found = FALSE;
+
+ if (check_col (pinfo->cinfo, COL_INFO))
+ col_clear (pinfo->cinfo, COL_INFO);
+
+
+ /* find or create the call_info for this call */
+ call_info = find_or_create_call_info(pinfo);
+
+ /* we may need to reverse the bit ordering before we go any further. */
+ if( call_info -> bitswapped ) {
+ tvbuff_t *reversed_tvb;
+ guint8 *data;
+ guint len;
+ guint i;
+
+ len = tvb_length(tvb);
+ data = g_malloc(len);
+ for( i=0; i<len; i++)
+ data[i]=BIT_SWAP(tvb_get_guint8(tvb,i));
+
+
+ reversed_tvb = tvb_new_real_data(data,len,tvb_reported_length(tvb));
+
+ /*
+ * Add the reversed tvbuff to the list of tvbuffs to which
+ * the tvbuff we were handed refers, so it'll get
+ * cleaned up when that tvbuff is cleaned up.
+ */
+ tvb_set_child_real_data_tvbuff(tvb, reversed_tvb);
+
+
+ /* Add a freer */
+ tvb_set_free_cb(reversed_tvb, g_free);
+
+ /* Add the reversed data to the data source list. */
+ add_new_data_source(pinfo, reversed_tvb, "Bit-swapped H.223 frame" );
+
+ tvb = reversed_tvb;
+ }
+
+ while( offset < tvb_reported_length( tvb )) {
+ gboolean pdu_found_this_fragment = FALSE;
+ offset = dissect_mux_pdu_fragment( tvb, offset, pinfo, &pkt_offset, tree,
+ &h223_tree, call_info,
+ &pdu_found_this_fragment );
+ if( pdu_found_this_fragment )
+ pdu_found = TRUE;
+ }
+
+ if( !pdu_found && check_col (pinfo->cinfo, COL_INFO))
+ col_set_str (pinfo->cinfo, COL_INFO, "(No complete PDUs)");
+
+ /* set up the protocol and info fields in the summary pane */
+ if (check_col (pinfo->cinfo, COL_PROTOCOL))
+ col_set_str (pinfo->cinfo, COL_PROTOCOL, PROTO_TAG_H223);
+}
+
+static void h223_init_protocol (void)
+{
+ circuit_chain_init();
+}
+
+
+void proto_register_h223 (void)
+{
+ /* A header field is something you can search/filter on.
+ *
+ * We create a structure to register our fields. It consists of an
+ * array of hf_register_info structures, each of which are of the format
+ * {&(field id), {name, abbrev, type, display, strings, bitmask, blurb, HFILL}}.
+ */
+
+ static hf_register_info hf[] = {
+ { &hf_h223_non_h223_data,
+ { "Non-H.223 data", "h223.non-h223", FT_NONE, BASE_NONE, NULL, 0x0,
+ "Initial data in stream, not a PDU", HFILL }},
+
+ { &hf_h223_mux_stuffing_pdu,
+ { "H.223 stuffing PDU", "h223.mux.stuffing", FT_NONE, BASE_NONE, NULL, 0x0,
+ "Empty PDU used for stuffing when no data available", HFILL }},
+
+ { &hf_h223_mux_pdu,
+ { "H.223 MUX-PDU", "h223.mux", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 MUX-PDU", HFILL }},
+
+ { &hf_h223_mux_header,
+ { "Header", "h223.mux.header", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 MUX header", HFILL }},
+
+ { &hf_h223_mux_rawhdr,
+ { "Raw value", "h223.mux.rawhdr", FT_UINT24, BASE_HEX, NULL, 0x0,
+ "Raw header bytes", HFILL }},
+
+ { &hf_h223_mux_correctedhdr,
+ { "Corrected value", "h223.mux.correctedhdr", FT_UINT24, BASE_HEX, NULL, 0x0,
+ "Corrected header bytes", HFILL }},
+
+ { &hf_h223_mux_mc,
+ { "Multiplex Code", "h223.mux.mc", FT_UINT8, BASE_DEC, NULL, 0x0,
+ "H.223 MUX multiplex code", HFILL }},
+
+ { &hf_h223_mux_mpl,
+ { "Multiplex Payload Length", "h223.mux.mpl", FT_UINT8, BASE_DEC, NULL, 0x0,
+ "H.223 MUX multiplex Payload Length", HFILL }},
+
+ { &hf_h223_mux_deact,
+ { "Deactivated multiplex table entry", "h223.mux.deactivated", FT_NONE, BASE_NONE, NULL, 0x0,
+ "mpl refers to an entry in the multiplex table which is not active", HFILL }},
+
+ { &hf_h223_mux_vc,
+ { "H.223 virtual circuit", "h223.mux.vc", FT_UINT16, BASE_DEC, NULL, 0x0,
+ "H.223 Virtual Circuit", HFILL }},
+
+ { &hf_h223_mux_extra,
+ { "Extraneous data", "h223.mux.extra", FT_NONE, BASE_DEC, NULL, 0x0,
+ "data beyond mpl", HFILL }},
+
+ { &hf_h223_mux_hdlc2,
+ { "HDLC flag", "h223.mux.hdlc", FT_UINT16, BASE_HEX, NULL, 0x0,
+ "framing flag", HFILL }},
+
+ /* fields for h.223-mux fragments */
+ { &hf_h223_mux_fragment_overlap,
+ { "Fragment overlap", "h223.mux.fragment.overlap", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Fragment overlaps with other fragments", HFILL }},
+
+ { &hf_h223_mux_fragment_overlap_conflict,
+ { "Conflicting data in fragment overlap", "h223.mux.fragment.overlap.conflict", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Overlapping fragments contained conflicting data", HFILL }},
+
+ { &hf_h223_mux_fragment_multiple_tails,
+ { "Multiple tail fragments found", "h223.mux.fragment.multipletails", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Several tails were found when defragmenting the packet", HFILL }},
+
+ { &hf_h223_mux_fragment_too_long_fragment,
+ { "Fragment too long", "h223.mux.fragment.toolongfragment", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Fragment contained data past end of packet", HFILL }},
+
+ { &hf_h223_mux_fragment_error,
+ { "Defragmentation error", "h223.mux.fragment.error", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+ "Defragmentation error due to illegal fragments", HFILL }},
+
+ { &hf_h223_mux_fragment,
+ { "H.223 MUX-PDU Fragment", "h223.mux.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+ "H.223 MUX-PDU Fragment", HFILL }},
+
+ { &hf_h223_mux_fragments,
+ { "H.223 MUX-PDU Fragments", "h223.mux.fragments", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 MUX-PDU Fragments", HFILL }},
+
+ { &hf_h223_mux_reassembled_in,
+ { "MUX-PDU fragment, reassembled in frame", "h223.mux.reassembled_in", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+ "This H.223 MUX-PDU packet is reassembled in this frame", HFILL }},
+
+ /* fields for h.223-al fragments */
+ { &hf_h223_al_fragment_overlap,
+ { "Fragment overlap", "h223.al.fragment.overlap", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Fragment overlaps with other fragments", HFILL }},
+
+ { &hf_h223_al_fragment_overlap_conflict,
+ { "Conflicting data in fragment overlap", "h223.al.fragment.overlap.conflict", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Overlapping fragments contained conflicting data", HFILL }},
+
+ { &hf_h223_al_fragment_multiple_tails,
+ { "Multiple tail fragments found", "h223.al.fragment.multipletails", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Several tails were found when defragmenting the packet", HFILL }},
+
+ { &hf_h223_al_fragment_too_long_fragment,
+ { "Fragment too long", "h223.al.fragment.toolongfragment", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "Fragment contained data past end of packet", HFILL }},
+
+ { &hf_h223_al_fragment_error,
+ { "Defragmentation error", "h223.al.fragment.error", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+ "Defragmentation error due to illegal fragments", HFILL }},
+
+ { &hf_h223_al_fragment,
+ { "H.223 AL-PDU Fragment", "h223.al.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+ "H.223 AL-PDU Fragment", HFILL }},
+
+ { &hf_h223_al_fragments,
+ { "H.223 AL-PDU Fragments", "h223.al.fragments", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 AL-PDU Fragments", HFILL }},
+
+ { &hf_h223_al_reassembled_in,
+ { "AL-PDU fragment, reassembled in frame", "h223.al.reassembled_in", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+ "This H.223 AL-PDU packet is reassembled in this frame", HFILL }},
+
+ /* h223-als */
+
+ { &hf_h223_al1,
+ { "H.223 AL1", "h223.al1", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 AL-PDU using AL1", HFILL }},
+
+ { &hf_h223_al1_framed,
+ { "H.223 AL1 framing", "h223.al1.framed", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "", HFILL }},
+
+ { &hf_h223_al2,
+ { "H.223 AL2", "h223.al2", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 AL-PDU using AL2", HFILL }},
+
+ { &hf_h223_al2_sequenced,
+ { "H.223 AL2 sequenced", "h223.al2.sequenced", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "", HFILL }},
+
+ { &hf_h223_al2_seqno,
+ { "Sequence Number", "h223.al2.seqno", FT_UINT8, BASE_DEC, NULL, 0x0,
+ "H.223 AL2 sequence number", HFILL }},
+
+ { &hf_h223_al2_crc,
+ { "CRC", "h223.al2.crc", FT_UINT8, BASE_HEX, NULL, 0x0,
+ "CRC", HFILL }},
+
+ { &hf_h223_al2_crc_bad,
+ { "Bad CRC","h223.al2.crc_bad", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+ "", HFILL }},
+
+ { &hf_h223_al_payload,
+ { "H.223 AL Payload", "h223.al.payload", FT_NONE, BASE_NONE, NULL, 0x0,
+ "H.223 AL-PDU Payload", HFILL }},
+
+ };
+
+ static gint *ett[] = {
+ &ett_h223,
+ &ett_h223_non_h223_data,
+ &ett_h223_mux_stuffing_pdu,
+ &ett_h223_mux_pdu,
+ &ett_h223_mux_header,
+ &ett_h223_mux_deact,
+ &ett_h223_mux_vc,
+ &ett_h223_mux_extra,
+ &ett_h223_mux_fragments,
+ &ett_h223_mux_fragment,
+ &ett_h223_al_fragments,
+ &ett_h223_al_fragment,
+ &ett_h223_al1,
+ &ett_h223_al2,
+ &ett_h223_al_payload
+ };
+
+ if (proto_h223 == -1) { /* execute protocol initialization only once */
+ proto_h223 =
+ proto_register_protocol ("ITU-T Recommendation H.223", "H.223", "h223");
+
+ proto_register_field_array (proto_h223, hf, array_length (hf));
+ proto_register_subtree_array (ett, array_length (ett));
+ register_dissector("h223", dissect_h223, proto_h223);
+
+ /* register our init routine to be called at the start of a capture,
+ to clear out our hash tables etc */
+ register_init_routine(&h223_init_protocol);
+ }
+
+ h245_set_h223_set_mc_handle( &h223_set_mc );
+ h245_set_h223_add_lc_handle( &h223_add_lc );
+}
+
+void proto_reg_handoff_h223(void)
+{
+ dissector_handle_t h223 = find_dissector("h223");
+ data_handle = find_dissector("data");
+ h245dg_handle = find_dissector("h245dg");
+ srp_handle = find_dissector("srp");
+
+ dissector_add_handle("tcp.port", h223);
+ dissector_add("iax2.dataformat", AST_DATAFORMAT_H223_H245, h223);
+}
+/* vim:set ts=8 et: */
git.samba.org / gd / wireshark / .git / commitdiff