static tvbuff_t *
handle_segment(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
guint32 pkt_id, guint16 pkt_len, guint16 seg_off)
{
fragment_head *frags;
int offset;
guint32 frag_data_len;
gboolean more_frags;
/* Skip fake TCP header after the first segment. */
if (seg_off == 0) {
offset = 0;
} else {
offset = STT_TCP_HDR_LEN;
/* We saved the TCP header on the first packet (only), which skews the
* segment offset. */
seg_off += STT_TCP_HDR_LEN;
}
frag_data_len = tvb_reported_length_remaining(tvb, offset);
more_frags = seg_off + frag_data_len < pkt_len;
frags = fragment_add_check(&stt_reassembly_table, tvb, offset, pinfo,
pkt_id, NULL, seg_off, frag_data_len,
more_frags);
/* Update reassembly fields in UI if reassembly is complete. */
if (frags) {
return process_reassembled_data(tvb, offset, pinfo, "Reassembled STT",
frags, &frag_items, NULL, tree);
}
return NULL;
}
static int
dissect_data_segment(proto_tree *ltp_tree, tvbuff_t *tvb,packet_info *pinfo,int frame_offset,int ltp_type, guint64 session_num){
guint64 client_id;
guint64 offset;
guint64 length;
guint64 chkp_sno = 0;
guint64 rpt_sno = 0;
int segment_offset = 0;
int client_id_size;
int offset_size;
int length_size;
int chkp_sno_size;
int rpt_sno_size;
int data_offset = 0;
int data_length;
int bundle_size = 0;
int dissected_data_size = 0;
int data_count = 1;
proto_item *ltp_data_item;
proto_item *ltp_data_data_item;
proto_tree *ltp_data_tree;
proto_tree *ltp_data_data_tree;
tvbuff_t *datatvb;
fragment_data *frag_msg = NULL;
gboolean more_frags = TRUE;
tvbuff_t *new_tvb = NULL;
/* Extract the info for the data segment */
client_id = evaluate_sdnv_64(tvb,frame_offset + segment_offset,&client_id_size);
segment_offset+= client_id_size;
if((unsigned)(frame_offset + segment_offset) >= tvb_length(tvb)){
/* This would mean the data segment is incomplete */
return 0;
}
offset = evaluate_sdnv_64(tvb,frame_offset + segment_offset,&offset_size);
segment_offset+= offset_size;
if((unsigned)(frame_offset + segment_offset) >= tvb_length(tvb)){
/* This would mean the data segment is incomplete */
return 0;
}
length = evaluate_sdnv_64(tvb,frame_offset + segment_offset,&length_size);
segment_offset+= length_size;
if((unsigned)(frame_offset + segment_offset) >= tvb_length(tvb)){
/* This would mean the data segment is incomplete */
return 0;
}
if(ltp_type != 0 )
{
chkp_sno = evaluate_sdnv_64(tvb,frame_offset + segment_offset,&chkp_sno_size);
segment_offset+= chkp_sno_size;
if((unsigned)(frame_offset + segment_offset) >= tvb_length(tvb)){
/* This would mean the data segment is incomplete */
return 0;
}
rpt_sno = evaluate_sdnv_64(tvb,frame_offset + segment_offset,&rpt_sno_size);
segment_offset+= rpt_sno_size;
if((unsigned)(frame_offset + segment_offset) >= tvb_length(tvb)){
/* This would mean the data segment is incomplete */
return 0;
}
}
/* Adding size of the data */
if ((segment_offset + (int)length < segment_offset) || (segment_offset + (int)length < (int)length)) {
/* Addition result has wrapped */
return 0;
}
segment_offset+= (int)length;
if ((segment_offset + frame_offset < segment_offset) || (segment_offset + frame_offset < frame_offset)) {
/* Addition result has wrapped */
return 0;
}
if((unsigned)(frame_offset + segment_offset) > tvb_length(tvb)){
/* This would mean the data segment is incomplete */
return 0;
}
/* Create a subtree for data segment and add the other fields under it */
ltp_data_item = proto_tree_add_text(ltp_tree, tvb,frame_offset, segment_offset, "Data Segment");
ltp_data_tree = proto_item_add_subtree(ltp_data_item, ett_data_segm);
proto_tree_add_uint64(ltp_data_tree,hf_ltp_data_clid, tvb, frame_offset,client_id_size,client_id);
frame_offset += client_id_size;
proto_tree_add_uint64(ltp_data_tree, hf_ltp_data_offset, tvb, frame_offset,offset_size, offset);
frame_offset += offset_size;
proto_tree_add_uint64(ltp_data_tree,hf_ltp_data_length, tvb, frame_offset,length_size,length);
frame_offset += length_size;
if(ltp_type != 0 )
{
proto_tree_add_uint64(ltp_data_tree, hf_ltp_data_chkp, tvb, frame_offset,chkp_sno_size, chkp_sno);
frame_offset += chkp_sno_size;
proto_tree_add_uint64(ltp_data_tree, hf_ltp_data_rpt, tvb, frame_offset,rpt_sno_size, rpt_sno);
frame_offset += rpt_sno_size;
more_frags = FALSE;
frag_msg = fragment_add_check(tvb, frame_offset, pinfo, (guint32)session_num, ltp_fragment_table,
ltp_reassembled_table, (guint32)offset, (guint32)length, more_frags);
}
else
{
more_frags = TRUE;
frag_msg = fragment_add_check(tvb, frame_offset, pinfo, (guint32)session_num, ltp_fragment_table,
ltp_reassembled_table, (guint32)offset, (guint32)length, more_frags);
}
if(frag_msg)
{
/* Checking if the segment is completely reassembled */
if(!(frag_msg->flags & FD_PARTIAL_REASSEMBLY))
{
/* if the segment has not been fragmented, then no reassembly is needed */
if(!more_frags && offset == 0)
{
new_tvb = tvb_new_subset(tvb,frame_offset,tvb_length(tvb)-frame_offset,-1);
}
else
{
new_tvb = process_reassembled_data(tvb, frame_offset, pinfo, "Reassembled LTP Segment",
frag_msg, <p_frag_items,NULL, ltp_data_tree);
}
}
}
if(new_tvb)
{
data_length = tvb_length(new_tvb);
while(dissected_data_size < data_length)
{
ltp_data_data_item = proto_tree_add_text(ltp_data_tree, tvb,frame_offset, 0, "Data[%d]",data_count);
ltp_data_data_tree = proto_item_add_subtree(ltp_data_data_item, ett_data_data_segm);
datatvb = tvb_new_subset(new_tvb, data_offset, (int)data_length - dissected_data_size, tvb_length(new_tvb));
bundle_size = dissect_complete_bundle(datatvb, pinfo, ltp_data_data_tree);
if(bundle_size == 0) { /*Couldn't parse bundle*/
col_set_str(pinfo->cinfo, COL_INFO, "Dissection Failed");
return 0; /*Give up*/
}
data_offset += bundle_size;
dissected_data_size += bundle_size;
data_count++;
}
}
else
{
if(frag_msg && more_frags)
{
col_append_fstr(pinfo->cinfo, COL_INFO, "[Reassembled in %d] ",frag_msg->reassembled_in);
}
else
{
col_append_str(pinfo->cinfo, COL_INFO, "[Unfinished LTP Segment] ");
}
}
return segment_offset;
}
static int
dissect_data_segment(proto_tree *ltp_tree, tvbuff_t *tvb,packet_info *pinfo,int frame_offset,int ltp_type, guint64 session_num)
{
guint64 client_id;
guint64 data_offset;
guint64 data_length;
guint64 chkp_sno = 0;
guint64 rpt_sno = 0;
guint64 sda_client_id = 0;
unsigned segment_size = 0;
int sdnv_length;
int sdnv_status;
proto_tree *ltp_data_tree;
proto_item *ti;
fragment_head *frag_msg = NULL;
gboolean more_frags = TRUE;
tvbuff_t *new_tvb = NULL;
/* Create a subtree for data segment and add the other fields under it */
ltp_data_tree = proto_tree_add_subtree(ltp_tree, tvb, frame_offset, tvb_captured_length_remaining(tvb, frame_offset), ett_data_segm, NULL, "Data Segment");
/* Client ID - 0 = Bundle Protocol, 1 = CCSDS LTP Service Data Aggregation */
sdnv_status = evaluate_sdnv64(tvb, frame_offset, &sdnv_length, &client_id);
ti = proto_tree_add_uint64_format_value(ltp_data_tree, hf_ltp_data_clid, tvb, frame_offset, sdnv_length, client_id,
"%" G_GINT64_MODIFIER "u (%s)", client_id,
val_to_str_const((const guint32) client_id, client_service_id_info, "Invalid"));
if (!sdnv_status) {
expert_add_info(pinfo, ti, &ei_ltp_sdnv_length);
return 0;
}
frame_offset += sdnv_length;
segment_size += sdnv_length;
/* data segment offset */
if ((sdnv_length = add_sdnv64_to_tree(ltp_data_tree, tvb, pinfo, frame_offset, hf_ltp_data_offset, &data_offset, &ti)) > 0) {
frame_offset += sdnv_length;
segment_size += sdnv_length;
} else {
return 0;
}
/* data segment length */
if ((sdnv_length = add_sdnv64_to_tree(ltp_data_tree, tvb, pinfo, frame_offset, hf_ltp_data_length, &data_length, &ti)) > 0) {
frame_offset += sdnv_length;
segment_size += sdnv_length;
/* add in the data length also */
segment_size += (unsigned int) data_length;
} else {
return 0;
}
more_frags = FALSE;
if (ltp_type != 0 && ltp_type < 4)
{
/* checkpoint serial number - 32 bits per CCSDS */
if ((sdnv_length = add_sdnv64_to_tree(ltp_data_tree, tvb, pinfo, frame_offset, hf_ltp_data_chkp, &chkp_sno, &ti)) > 0) {
frame_offset += sdnv_length;
segment_size += sdnv_length;
if (chkp_sno > 4294967295U) {
/* just a warning - continue processing */
expert_add_info(pinfo, ti, &ei_ltp_sno_larger_than_ccsds);
}
} else {
return 0;
}
/* report serial number - 32 bits per CCSDS */
if ((sdnv_length = add_sdnv64_to_tree(ltp_data_tree, tvb, pinfo, frame_offset, hf_ltp_data_rpt, &rpt_sno, &ti)) > 0) {
frame_offset += sdnv_length;
segment_size += sdnv_length;
if (rpt_sno > 4294967295U) {
/* just a warning - continue processing */
expert_add_info(pinfo, ti, &ei_ltp_sno_larger_than_ccsds);
}
} else {
return 0;
}
} else if (ltp_type != 7) {
more_frags = TRUE;
}
if (segment_size >= tvb_captured_length(tvb)) {
/* did not capture the entire packet */
proto_tree_add_string(ltp_data_tree, hf_ltp_partial_packet, tvb, 0, 0, "<increase capture size?>");
return tvb_captured_length(tvb);
}
frag_msg = fragment_add_check(<p_reassembly_table,
tvb, frame_offset, pinfo, (guint32)session_num, NULL,
(guint32)data_offset, (guint32)data_length, more_frags);
if(frag_msg)
{
/* Checking if the segment is completely reassembled */
if(!(frag_msg->flags & FD_PARTIAL_REASSEMBLY))
{
/* if the segment has not been fragmented, then no reassembly is needed */
if(!more_frags && data_offset == 0)
{
new_tvb = tvb_new_subset_remaining(tvb, frame_offset);
}
else
{
new_tvb = process_reassembled_data(tvb, frame_offset, pinfo, "Reassembled LTP Segment",
frag_msg, <p_frag_items,NULL, ltp_data_tree);
}
}
}
if(new_tvb)
{
int data_count = 1;
int parse_length;
int parse_offset = 0;
parse_length = tvb_captured_length(new_tvb);
while(parse_offset < parse_length)
{
int bundle_size;
int sda_header_size;
proto_tree *ltp_data_data_tree;
tvbuff_t *datatvb;
ltp_data_data_tree = proto_tree_add_subtree_format(ltp_data_tree, tvb,frame_offset, 0,
ett_data_data_segm, NULL, "Data[%d]",data_count);
sda_header_size = 0;
if (client_id == 2) {
sdnv_status = evaluate_sdnv64(tvb, frame_offset+parse_offset, &sdnv_length, &sda_client_id);
ti = proto_tree_add_uint64_format_value(ltp_data_data_tree, hf_ltp_data_sda_clid, tvb, frame_offset+parse_offset, sdnv_length, sda_client_id,
"%" G_GINT64_MODIFIER "u (%s)", sda_client_id, val_to_str_const((const guint32) sda_client_id, client_service_id_info, "Invalid"));
if (!sdnv_status) {
expert_add_info(pinfo, ti, &ei_ltp_sdnv_length);
return 0;
}
sda_header_size = sdnv_length;
parse_offset += sdnv_length;
if (parse_offset == parse_length) {
col_set_str(pinfo->cinfo, COL_INFO, "CCSDS LTP SDA Protocol Error");
return 0; /* Give up*/
}
}
datatvb = tvb_new_subset_length_caplen(new_tvb, parse_offset, (int)parse_length - parse_offset, tvb_captured_length(new_tvb));
bundle_size = call_dissector(bundle_handle, datatvb, pinfo, ltp_data_data_tree);
if(bundle_size == 0) { /*Couldn't parse bundle*/
col_set_str(pinfo->cinfo, COL_INFO, "Dissection Failed");
return 0; /*Give up*/
}
/* update the length of the data set */
proto_item_set_len(ltp_data_data_tree, bundle_size+sda_header_size);
parse_offset += bundle_size;
data_count++;
}
}
else
{
if(frag_msg && more_frags)
{
col_append_frame_number(pinfo, COL_INFO, "[Reassembled in %d] ",frag_msg->reassembled_in);
}
else
{
col_append_str(pinfo->cinfo, COL_INFO, "[Unfinished LTP Segment] ");
}
}
return segment_size;
}
static void
dissect_gsm_cell_broadcast(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
guint8 sms_encoding, total_pages, current_page;
guint32 offset = 0;
guint32 len, msg_key;
proto_item *cbs_page_item = NULL;
proto_tree *cbs_page_tree = NULL;
guint16 serial_number, message_id;
tvbuff_t *cbs_page_tvb = NULL;
tvbuff_t *cbs_msg_tvb = NULL;
fragment_data * frag_data = NULL;
len = tvb_length(tvb);
col_append_str(pinfo->cinfo, COL_PROTOCOL, " Cell Broadcast");
col_append_str(pinfo->cinfo, COL_INFO, " (CBS Page)");
cbs_page_item = proto_tree_add_protocol_format(proto_tree_get_root(tree), proto_cell_broadcast, tvb, 0, len, "GSM Cell Broadcast");
cbs_page_tree = proto_item_add_subtree(cbs_page_item, ett_gsm_cbs_page);
serial_number = tvb_get_ntohs(tvb, offset);
offset += dissect_cbs_serial_number(tvb, cbs_page_tree, offset);
message_id = tvb_get_ntohs(tvb, offset);
offset += dissect_cbs_message_identifier(tvb, cbs_page_tree, offset);
sms_encoding = dissect_cbs_data_coding_scheme(tvb, pinfo, cbs_page_tree, offset++);
total_pages = tvb_get_guint8(tvb, offset);
current_page = (total_pages & 0xF0) >> 4;
total_pages &= 0x0F;
proto_tree_add_item(cbs_page_tree, hf_gsm_cbs_current_page, tvb, offset, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(cbs_page_tree, hf_gsm_cbs_total_pages, tvb, offset++, 1, ENC_BIG_ENDIAN);
cbs_page_tvb = dissect_cbs_data(sms_encoding, tvb, cbs_page_tree, pinfo, offset );
if (cbs_page_tvb != NULL)
{
if (tree != NULL)
{
proto_item *item = proto_tree_add_text(cbs_page_tree, tvb, offset, -1, "Cell Broadcast Page Contents");
proto_tree *cbs_page_subtree = proto_item_add_subtree(item, ett_gsm_cbs_page_content);
gint len = tvb_length(cbs_page_tvb);
proto_tree_add_string(cbs_page_subtree, hf_gsm_cbs_page_content, cbs_page_tvb, 0, len, tvb_get_ephemeral_string(cbs_page_tvb, 0, len));
}
if (total_pages == 1)
{
/* no need for reassembly */
cbs_msg_tvb = cbs_page_tvb;
}
else
{
/* now we have a complete page, try to concatenate the full message */
/* we can use the serial number and message ID as keys, as they are the same for all pages of a message */
msg_key = (serial_number << 16) + message_id;
frag_data = fragment_add_check(cbs_page_tvb, 0, pinfo, msg_key,
gsm_cbs_page_table, gsm_cbs_message_table,
((current_page -1) * GSM_CBS_PAGE_SIZE),
GSM_CBS_PAGE_SIZE, (current_page!=total_pages));
cbs_msg_tvb = process_reassembled_data(cbs_page_tvb, 0, pinfo, "Reassembled Cell Broadcast message",
frag_data, &gsm_page_items, NULL, cbs_page_tree);
}
}
if ((tree != NULL) && (cbs_msg_tvb != NULL))
{
guint16 len;
proto_item *cbs_msg_item = NULL;
proto_tree *cbs_msg_tree = NULL;
len = tvb_length(cbs_msg_tvb);
col_append_str(pinfo->cinfo, COL_INFO, " (CBS Message)");
cbs_msg_item = proto_tree_add_protocol_format(proto_tree_get_root(tree), proto_cell_broadcast, cbs_msg_tvb, 0, len, "GSM Cell Broadcast Message");
cbs_msg_tree = proto_item_add_subtree(cbs_msg_item, ett_cbs_msg);
proto_tree_add_string(cbs_msg_tree, hf_gsm_cbs_message_content, cbs_msg_tvb, 0, len, tvb_get_ephemeral_string(cbs_msg_tvb, 0, len));
}
}
static void
dissect_clnp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *clnp_tree;
proto_item *ti, *ti_len = NULL, *ti_pdu_len = NULL, *ti_tot_len = NULL;
guint8 cnf_proto_id;
guint8 cnf_hdr_len;
guint8 cnf_vers;
guint8 cnf_ttl;
guint8 cnf_type;
char flag_string[6+1];
const char *pdu_type_string;
proto_tree *type_tree;
guint16 segment_length;
guint16 du_id = 0;
guint16 segment_offset = 0;
guint16 total_length;
guint16 cnf_cksum;
cksum_status_t cksum_status;
int offset;
guchar src_len, dst_len, nsel, opt_len = 0;
const guint8 *dst_addr, *src_addr;
guint next_length;
proto_tree *discpdu_tree;
gboolean save_in_error_pkt;
fragment_head *fd_head;
tvbuff_t *next_tvb;
gboolean update_col_info = TRUE;
gboolean save_fragmented;
heur_dtbl_entry_t *hdtbl_entry;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "CLNP");
col_clear(pinfo->cinfo, COL_INFO);
cnf_proto_id = tvb_get_guint8(tvb, P_CLNP_PROTO_ID);
if (cnf_proto_id == NLPID_NULL) {
col_set_str(pinfo->cinfo, COL_INFO, "Inactive subset");
ti = proto_tree_add_item(tree, proto_clnp, tvb, P_CLNP_PROTO_ID, 1, ENC_NA);
clnp_tree = proto_item_add_subtree(ti, ett_clnp);
proto_tree_add_uint_format(clnp_tree, hf_clnp_id, tvb, P_CLNP_PROTO_ID, 1,
cnf_proto_id, "Inactive subset");
next_tvb = tvb_new_subset_remaining(tvb, 1);
if (call_dissector(ositp_inactive_handle, next_tvb, pinfo, tree) == 0)
call_dissector(data_handle,tvb, pinfo, tree);
return;
}
/* return if version not known */
cnf_vers = tvb_get_guint8(tvb, P_CLNP_VERS);
if (cnf_vers != ISO8473_V1) {
call_dissector(data_handle,tvb, pinfo, tree);
return;
}
/* fixed part decoding */
cnf_hdr_len = tvb_get_guint8(tvb, P_CLNP_HDR_LEN);
ti = proto_tree_add_item(tree, proto_clnp, tvb, 0, cnf_hdr_len, ENC_NA);
clnp_tree = proto_item_add_subtree(ti, ett_clnp);
proto_tree_add_uint(clnp_tree, hf_clnp_id, tvb, P_CLNP_PROTO_ID, 1,
cnf_proto_id);
ti_len = proto_tree_add_uint(clnp_tree, hf_clnp_length, tvb, P_CLNP_HDR_LEN, 1,
cnf_hdr_len);
if (cnf_hdr_len < FIXED_PART_LEN) {
/* Header length is less than the length of the fixed part of
the header. */
expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
"Header length value < minimum length %u",
FIXED_PART_LEN);
return;
}
proto_tree_add_uint(clnp_tree, hf_clnp_version, tvb, P_CLNP_VERS, 1,
cnf_vers);
cnf_ttl = tvb_get_guint8(tvb, P_CLNP_TTL);
proto_tree_add_uint_format(clnp_tree, hf_clnp_ttl, tvb, P_CLNP_TTL, 1,
cnf_ttl,
"Holding Time : %u (%u.%u secs)",
cnf_ttl, cnf_ttl / 2, (cnf_ttl % 2) * 5);
cnf_type = tvb_get_guint8(tvb, P_CLNP_TYPE);
pdu_type_string = val_to_str(cnf_type & CNF_TYPE, npdu_type_abbrev_vals,
"Unknown (0x%02x)");
flag_string[0] = '\0';
if (cnf_type & CNF_SEG_OK)
g_strlcat(flag_string, "S ", 7);
if (cnf_type & CNF_MORE_SEGS)
g_strlcat(flag_string, "M ", 7);
if (cnf_type & CNF_ERR_OK)
g_strlcat(flag_string, "E ", 7);
ti = proto_tree_add_uint_format(clnp_tree, hf_clnp_type, tvb, P_CLNP_TYPE, 1,
cnf_type,
"PDU Type : 0x%02x (%s%s)",
cnf_type,
flag_string,
pdu_type_string);
type_tree = proto_item_add_subtree(ti, ett_clnp_type);
proto_tree_add_item(type_tree, hf_clnp_cnf_segmentation, tvb, P_CLNP_TYPE, 1, ENC_NA);
proto_tree_add_item(type_tree, hf_clnp_cnf_more_segments, tvb, P_CLNP_TYPE, 1, ENC_NA);
proto_tree_add_item(type_tree, hf_clnp_cnf_report_error, tvb, P_CLNP_TYPE, 1, ENC_NA);
proto_tree_add_item(type_tree, hf_clnp_cnf_type, tvb, P_CLNP_TYPE, 1, ENC_NA);
/* If we don't have the full header - i.e., not enough to see the
segmentation part and determine whether this datagram is segmented
or not - set the Info column now; we'll get an exception before
we set it otherwise. */
if (tvb_length(tvb) < cnf_hdr_len) {
col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
}
segment_length = tvb_get_ntohs(tvb, P_CLNP_SEGLEN);
ti_pdu_len = proto_tree_add_uint(clnp_tree, hf_clnp_pdu_length, tvb, P_CLNP_SEGLEN, 2,
segment_length);
if (segment_length < cnf_hdr_len) {
/* Segment length is less than the header length. */
expert_add_info_format(pinfo, ti_pdu_len, &ei_clnp_length,
"PDU length < header length %u", cnf_hdr_len);
return;
}
cnf_cksum = tvb_get_ntohs(tvb, P_CLNP_CKSUM);
cksum_status = calc_checksum(tvb, 0, cnf_hdr_len, cnf_cksum);
switch (cksum_status) {
default:
/*
* No checksum present, or not enough of the header present to
* checksum it.
*/
proto_tree_add_uint(clnp_tree, hf_clnp_checksum, tvb,
P_CLNP_CKSUM, 2,
cnf_cksum);
break;
case CKSUM_OK:
/*
* Checksum is correct.
*/
proto_tree_add_uint_format_value(clnp_tree, hf_clnp_checksum, tvb,
P_CLNP_CKSUM, 2,
cnf_cksum,
"0x%04x (correct)",
cnf_cksum);
break;
case CKSUM_NOT_OK:
/*
* Checksum is not correct.
*/
proto_tree_add_uint_format_value(clnp_tree, hf_clnp_checksum, tvb,
P_CLNP_CKSUM, 2,
cnf_cksum,
"0x%04x (incorrect)",
cnf_cksum);
break;
}
opt_len = cnf_hdr_len;
opt_len -= FIXED_PART_LEN; /* Fixed part of Header */
/* address part */
offset = P_CLNP_ADDRESS_PART;
if (opt_len < 1) {
/* Header length is less than the minimum value in CLNP,
including the destination address length. */
expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
"Header length value < %u",
FIXED_PART_LEN + 1);
return;
}
dst_len = tvb_get_guint8(tvb, offset);
if (tree) {
proto_tree_add_uint(clnp_tree, hf_clnp_dest_length, tvb, offset, 1,
dst_len);
}
offset += 1;
opt_len -= 1;
if (opt_len < dst_len) {
/* Header length is less than the minimum value,
including the destination address length and the
destination address. */
expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
"Header length value < %u",
FIXED_PART_LEN + 1 + dst_len);
return;
}
dst_addr = tvb_get_ptr(tvb, offset, dst_len);
nsel = tvb_get_guint8(tvb, offset + dst_len - 1);
SET_ADDRESS(&pinfo->net_dst, AT_OSI, dst_len, dst_addr);
SET_ADDRESS(&pinfo->dst, AT_OSI, dst_len, dst_addr);
proto_tree_add_bytes_format_value(clnp_tree, hf_clnp_dest, tvb, offset, dst_len,
dst_addr,
"%s",
print_nsap_net(dst_addr, dst_len));
offset += dst_len;
opt_len -= dst_len;
if (opt_len < 1) {
/* Header length is less than the minimum value,
including the destination address length, the
destination address, and the source address length. */
expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
"Header length value < %u",
FIXED_PART_LEN + 1 + dst_len + 1);
return;
}
src_len = tvb_get_guint8(tvb, offset);
if (tree) {
proto_tree_add_uint(clnp_tree, hf_clnp_src_length, tvb,
offset, 1, src_len);
}
offset += 1;
opt_len -= 1;
if (opt_len < src_len) {
/* Header length is less than the minimum value,
including the destination address length, the
destination address, the source address length,
and the source address. */
expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
"Header length value < %u",
FIXED_PART_LEN + 1 + dst_len + 1 + src_len);
return;
}
src_addr = tvb_get_ptr(tvb, offset, src_len);
SET_ADDRESS(&pinfo->net_src, AT_OSI, src_len, src_addr);
SET_ADDRESS(&pinfo->src, AT_OSI, src_len, src_addr);
proto_tree_add_bytes_format_value(clnp_tree, hf_clnp_src, tvb,
offset, src_len,
src_addr,
"%s",
print_nsap_net(src_addr, src_len));
offset += src_len;
opt_len -= src_len;
/* Segmentation Part */
if (cnf_type & CNF_SEG_OK) {
if (opt_len < SEGMENTATION_PART_LEN) {
/* Header length is less than the minimum value,
including the destination address length, the
destination address, the source address length,
the source address, and the segmentation part. */
expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
"Header length value < %u",
FIXED_PART_LEN + 1 + dst_len + 1 + SEGMENTATION_PART_LEN);
return;
}
du_id = tvb_get_ntohs(tvb, offset);
proto_tree_add_text(clnp_tree, tvb, offset, 2,
"Data unit identifier: %06u",
du_id);
segment_offset = tvb_get_ntohs(tvb, offset + 2);
proto_tree_add_text(clnp_tree, tvb, offset + 2 , 2,
"Segment offset : %6u",
segment_offset);
total_length = tvb_get_ntohs(tvb, offset + 4);
ti_tot_len = proto_tree_add_text(clnp_tree, tvb, offset + 4 , 2,
"Total length : %6u",
total_length);
if (total_length < segment_length) {
/* Reassembled length is less than the length of this segment. */
expert_add_info_format(pinfo, ti_tot_len, &ei_clnp_length,
"Total length < segment length %u", segment_length);
return;
}
offset += SEGMENTATION_PART_LEN;
opt_len -= SEGMENTATION_PART_LEN;
}
dissect_osi_options(opt_len, tvb, offset, clnp_tree);
offset += opt_len;
/* If clnp_reassemble is on, this is a segment, we have all the
* data in the segment, and the checksum is valid, then just add the
* segment to the hashtable.
*/
save_fragmented = pinfo->fragmented;
if (clnp_reassemble && (cnf_type & CNF_SEG_OK) &&
((cnf_type & CNF_MORE_SEGS) || segment_offset != 0) &&
tvb_bytes_exist(tvb, offset, segment_length - cnf_hdr_len) &&
segment_length > cnf_hdr_len &&
cksum_status != CKSUM_NOT_OK) {
fd_head = fragment_add_check(&clnp_reassembly_table,
tvb, offset, pinfo, du_id, NULL,
segment_offset, segment_length - cnf_hdr_len,
cnf_type & CNF_MORE_SEGS);
next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled CLNP",
fd_head, &clnp_frag_items, &update_col_info, clnp_tree);
} else {
/* If this is the first segment, dissect its contents, otherwise
just show it as a segment.
XXX - if we eventually don't save the reassembled contents of all
segmented datagrams, we may want to always reassemble. */
if ((cnf_type & CNF_SEG_OK) && segment_offset != 0) {
/* Not the first segment - don't dissect it. */
next_tvb = NULL;
} else {
/* First segment, or not segmented. Dissect what we have here. */
/* Get a tvbuff for the payload. Set its length to the segment
length, and flag it as a fragment, so going past the end
reports FragmentBoundsError, i.e. "there's data missing
because this isn't reassembled", not ReportedBoundsError,
i.e. "the dissector ran past the end of the packet, so the
packet must not have been constructed properly". */
next_tvb = tvb_new_subset_length(tvb, offset, segment_length - cnf_hdr_len);
tvb_set_fragment(next_tvb);
/*
* If this is the first segment, but not the only segment,
* tell the next protocol that.
*/
if ((cnf_type & (CNF_SEG_OK|CNF_MORE_SEGS)) == (CNF_SEG_OK|CNF_MORE_SEGS))
pinfo->fragmented = TRUE;
else
pinfo->fragmented = FALSE;
}
}
if (next_tvb == NULL) {
/* Just show this as a segment. */
col_add_fstr(pinfo->cinfo, COL_INFO, "Fragmented %s NPDU %s(off=%u)",
pdu_type_string, flag_string, segment_offset);
/* As we haven't reassembled anything, we haven't changed "pi", so
we don't have to restore it. */
call_dissector(data_handle, tvb_new_subset_remaining(tvb, offset), pinfo,
tree);
pinfo->fragmented = save_fragmented;
return;
}
if (tvb_offset_exists(tvb, offset)) {
switch (cnf_type & CNF_TYPE) {
case DT_NPDU:
case MD_NPDU:
/* Continue with COTP if any data.
XXX - if this isn't the first Derived PDU of a segmented Initial
PDU, skip that? */
if (nsel==NSEL_NET && tvb_get_guint8(next_tvb, 0)==NLPID_ISO10747_IDRP) {
if(call_dissector(idrp_handle, next_tvb, pinfo, tree) != 0) {
pinfo->fragmented = save_fragmented;
return;
}
}
if (nsel == (guchar)tp_nsap_selector || always_decode_transport) {
if (call_dissector(ositp_handle, next_tvb, pinfo, tree) != 0) {
pinfo->fragmented = save_fragmented;
return; /* yes, it appears to be COTP or CLTP */
}
}
if (dissector_try_heuristic(clnp_heur_subdissector_list, next_tvb,
pinfo, tree, &hdtbl_entry, NULL)) {
pinfo->fragmented = save_fragmented;
return; /* yes, it appears to be one of the protocols in the heuristic list */
}
break;
case ER_NPDU:
/* The payload is the header and "none, some, or all of the data
part of the discarded PDU", i.e. it's like an ICMP error;
dissect it as a CLNP PDU. */
col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
next_length = tvb_length_remaining(tvb, offset);
if (next_length != 0) {
/* We have payload; dissect it. */
ti = proto_tree_add_text(clnp_tree, tvb, offset, next_length,
"Discarded PDU");
discpdu_tree = proto_item_add_subtree(ti, ett_clnp_disc_pdu);
/* Save the current value of the "we're inside an error packet"
flag, and set that flag; subdissectors may treat packets
that are the payload of error packets differently from
"real" packets. */
save_in_error_pkt = pinfo->flags.in_error_pkt;
pinfo->flags.in_error_pkt = TRUE;
call_dissector(clnp_handle, next_tvb, pinfo, discpdu_tree);
/* Restore the "we're inside an error packet" flag. */
pinfo->flags.in_error_pkt = save_in_error_pkt;
}
pinfo->fragmented = save_fragmented;
return; /* we're done with this PDU */
case ERQ_NPDU:
case ERP_NPDU:
/* XXX - dissect this */
break;
}
}
col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
call_dissector(data_handle,next_tvb, pinfo, tree);
pinfo->fragmented = save_fragmented;
} /* dissect_clnp */
static void
dissect_clnp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *clnp_tree = NULL;
proto_item *ti;
guint8 cnf_proto_id;
guint8 cnf_hdr_len;
guint8 cnf_vers;
guint8 cnf_ttl;
guint8 cnf_type;
char flag_string[6+1];
const char *pdu_type_string;
proto_tree *type_tree;
guint16 segment_length;
guint16 du_id = 0;
guint16 segment_offset = 0;
guint16 cnf_cksum;
cksum_status_t cksum_status;
int offset;
guchar src_len, dst_len, nsel, opt_len = 0;
const guint8 *dst_addr, *src_addr;
guint next_length;
proto_tree *discpdu_tree;
gboolean save_in_error_pkt;
fragment_data *fd_head;
tvbuff_t *next_tvb;
gboolean update_col_info = TRUE;
gboolean save_fragmented;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "CLNP");
col_clear(pinfo->cinfo, COL_INFO);
cnf_proto_id = tvb_get_guint8(tvb, P_CLNP_PROTO_ID);
if (cnf_proto_id == NLPID_NULL) {
col_set_str(pinfo->cinfo, COL_INFO, "Inactive subset");
if (tree) {
ti = proto_tree_add_item(tree, proto_clnp, tvb, P_CLNP_PROTO_ID, 1, ENC_NA);
clnp_tree = proto_item_add_subtree(ti, ett_clnp);
proto_tree_add_uint_format(clnp_tree, hf_clnp_id, tvb, P_CLNP_PROTO_ID, 1,
cnf_proto_id,
"Inactive subset");
}
next_tvb = tvb_new_subset_remaining(tvb, 1);
if (call_dissector(ositp_inactive_handle, next_tvb, pinfo, tree) == 0)
call_dissector(data_handle,tvb, pinfo, tree);
return;
}
/* return if version not known */
cnf_vers = tvb_get_guint8(tvb, P_CLNP_VERS);
if (cnf_vers != ISO8473_V1) {
call_dissector(data_handle,tvb, pinfo, tree);
return;
}
/* fixed part decoding */
cnf_hdr_len = tvb_get_guint8(tvb, P_CLNP_HDR_LEN);
opt_len = cnf_hdr_len;
if (tree) {
ti = proto_tree_add_item(tree, proto_clnp, tvb, 0, cnf_hdr_len, ENC_NA);
clnp_tree = proto_item_add_subtree(ti, ett_clnp);
proto_tree_add_uint(clnp_tree, hf_clnp_id, tvb, P_CLNP_PROTO_ID, 1,
cnf_proto_id);
proto_tree_add_uint(clnp_tree, hf_clnp_length, tvb, P_CLNP_HDR_LEN, 1,
cnf_hdr_len);
proto_tree_add_uint(clnp_tree, hf_clnp_version, tvb, P_CLNP_VERS, 1,
cnf_vers);
cnf_ttl = tvb_get_guint8(tvb, P_CLNP_TTL);
proto_tree_add_uint_format(clnp_tree, hf_clnp_ttl, tvb, P_CLNP_TTL, 1,
cnf_ttl,
"Holding Time : %u (%u.%u secs)",
cnf_ttl, cnf_ttl / 2, (cnf_ttl % 2) * 5);
}
cnf_type = tvb_get_guint8(tvb, P_CLNP_TYPE);
pdu_type_string = val_to_str(cnf_type & CNF_TYPE, npdu_type_abbrev_vals,
"Unknown (0x%02x)");
flag_string[0] = '\0';
if (cnf_type & CNF_SEG_OK)
g_strlcat(flag_string, "S ", 7);
if (cnf_type & CNF_MORE_SEGS)
g_strlcat(flag_string, "M ", 7);
if (cnf_type & CNF_ERR_OK)
g_strlcat(flag_string, "E ", 7);
if (tree) {
ti = proto_tree_add_uint_format(clnp_tree, hf_clnp_type, tvb, P_CLNP_TYPE, 1,
cnf_type,
"PDU Type : 0x%02x (%s%s)",
cnf_type,
flag_string,
pdu_type_string);
type_tree = proto_item_add_subtree(ti, ett_clnp_type);
proto_tree_add_text(type_tree, tvb, P_CLNP_TYPE, 1, "%s",
decode_boolean_bitfield(cnf_type, CNF_SEG_OK, 8,
"Segmentation permitted",
"Segmentation not permitted"));
proto_tree_add_text(type_tree, tvb, P_CLNP_TYPE, 1, "%s",
decode_boolean_bitfield(cnf_type, CNF_MORE_SEGS, 8,
"More segments",
"Last segment"));
proto_tree_add_text(type_tree, tvb, P_CLNP_TYPE, 1, "%s",
decode_boolean_bitfield(cnf_type, CNF_ERR_OK, 8,
"Report error if PDU discarded",
"Don't report error if PDU discarded"));
proto_tree_add_text(type_tree, tvb, P_CLNP_TYPE, 1, "%s",
decode_enumerated_bitfield(cnf_type, CNF_TYPE, 8,
npdu_type_vals, "%s"));
}
/* If we don't have the full header - i.e., not enough to see the
segmentation part and determine whether this datagram is segmented
or not - set the Info column now; we'll get an exception before
we set it otherwise. */
if (tvb_length(tvb) < cnf_hdr_len) {
col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
}
segment_length = tvb_get_ntohs(tvb, P_CLNP_SEGLEN);
cnf_cksum = tvb_get_ntohs(tvb, P_CLNP_CKSUM);
cksum_status = calc_checksum(tvb, 0, cnf_hdr_len, cnf_cksum);
if (tree) {
proto_tree_add_uint(clnp_tree, hf_clnp_pdu_length, tvb, P_CLNP_SEGLEN, 2,
segment_length);
switch (cksum_status) {
default:
/*
* No checksum present, or not enough of the header present to
* checksum it.
*/
proto_tree_add_uint_format(clnp_tree, hf_clnp_checksum, tvb,
P_CLNP_CKSUM, 2,
cnf_cksum,
"Checksum : 0x%04x",
cnf_cksum);
break;
case CKSUM_OK:
/*
* Checksum is correct.
*/
proto_tree_add_uint_format(clnp_tree, hf_clnp_checksum, tvb,
P_CLNP_CKSUM, 2,
cnf_cksum,
"Checksum : 0x%04x (correct)",
cnf_cksum);
break;
case CKSUM_NOT_OK:
/*
* Checksum is not correct.
*/
proto_tree_add_uint_format(clnp_tree, hf_clnp_checksum, tvb,
P_CLNP_CKSUM, 2,
cnf_cksum,
"Checksum : 0x%04x (incorrect)",
cnf_cksum);
break;
}
opt_len -= 9; /* Fixed part of Hesder */
} /* tree */
/* address part */
offset = P_CLNP_ADDRESS_PART;
dst_len = tvb_get_guint8(tvb, offset);
dst_addr = tvb_get_ptr(tvb, offset + 1, dst_len);
nsel = tvb_get_guint8(tvb, offset + dst_len);
src_len = tvb_get_guint8(tvb, offset + dst_len + 1);
src_addr = tvb_get_ptr(tvb, offset + dst_len + 2, src_len);
if (tree) {
proto_tree_add_uint(clnp_tree, hf_clnp_dest_length, tvb, offset, 1,
dst_len);
proto_tree_add_bytes_format(clnp_tree, hf_clnp_dest, tvb, offset + 1 , dst_len,
dst_addr,
" DA : %s",
print_nsap_net(dst_addr, dst_len));
proto_tree_add_uint(clnp_tree, hf_clnp_src_length, tvb,
offset + 1 + dst_len, 1, src_len);
proto_tree_add_bytes_format(clnp_tree, hf_clnp_src, tvb,
offset + dst_len + 2, src_len,
src_addr,
" SA : %s",
print_nsap_net(src_addr, src_len));
opt_len -= dst_len + src_len +2;
}
SET_ADDRESS(&pinfo->net_src, AT_OSI, src_len, src_addr);
SET_ADDRESS(&pinfo->src, AT_OSI, src_len, src_addr);
SET_ADDRESS(&pinfo->net_dst, AT_OSI, dst_len, dst_addr);
SET_ADDRESS(&pinfo->dst, AT_OSI, dst_len, dst_addr);
/* Segmentation Part */
offset += dst_len + src_len + 2;
if (cnf_type & CNF_SEG_OK) {
#if 0
struct clnp_segment seg; /* XXX - not used */
tvb_memcpy(tvb, (guint8 *)&seg, offset, sizeof(seg)); /* XXX - not used */
#endif
segment_offset = tvb_get_ntohs(tvb, offset + 2);
du_id = tvb_get_ntohs(tvb, offset);
if (tree) {
proto_tree_add_text(clnp_tree, tvb, offset, 2,
"Data unit identifier: %06u",
du_id);
proto_tree_add_text(clnp_tree, tvb, offset + 2 , 2,
"Segment offset : %6u",
segment_offset);
proto_tree_add_text(clnp_tree, tvb, offset + 4 , 2,
"Total length : %6u",
tvb_get_ntohs(tvb, offset + 4));
}
offset += 6;
opt_len -= 6;
}
if (tree) {
/* To do : decode options */
#if 0
proto_tree_add_text(clnp_tree, tvb, offset,
cnf_hdr_len - offset,
"Options/Data: <not shown>");
#endif
/* QUICK HACK Option Len:= PDU_Hd_length-( FixedPart+AddresPart+SegmentPart )*/
dissect_osi_options( opt_len,
tvb, offset, clnp_tree );
}
offset = cnf_hdr_len;
/* If clnp_reassemble is on, this is a segment, we have all the
* data in the segment, and the checksum is valid, then just add the
* segment to the hashtable.
*/
save_fragmented = pinfo->fragmented;
if (clnp_reassemble && (cnf_type & CNF_SEG_OK) &&
((cnf_type & CNF_MORE_SEGS) || segment_offset != 0) &&
tvb_bytes_exist(tvb, offset, segment_length - cnf_hdr_len) &&
segment_length > cnf_hdr_len &&
cksum_status != CKSUM_NOT_OK) {
fd_head = fragment_add_check(tvb, offset, pinfo, du_id, clnp_segment_table,
clnp_reassembled_table, segment_offset,
segment_length - cnf_hdr_len,
cnf_type & CNF_MORE_SEGS);
next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled CLNP",
fd_head, &clnp_frag_items, &update_col_info, clnp_tree);
} else {
/* If this is the first segment, dissect its contents, otherwise
just show it as a segment.
XXX - if we eventually don't save the reassembled contents of all
segmented datagrams, we may want to always reassemble. */
if ((cnf_type & CNF_SEG_OK) && segment_offset != 0) {
/* Not the first segment - don't dissect it. */
next_tvb = NULL;
} else {
/* First segment, or not segmented. Dissect what we have here. */
/* Get a tvbuff for the payload. */
next_tvb = tvb_new_subset_remaining(tvb, offset);
/*
* If this is the first segment, but not the only segment,
* tell the next protocol that.
*/
if ((cnf_type & (CNF_SEG_OK|CNF_MORE_SEGS)) == (CNF_SEG_OK|CNF_MORE_SEGS))
pinfo->fragmented = TRUE;
else
pinfo->fragmented = FALSE;
}
}
if (next_tvb == NULL) {
/* Just show this as a segment. */
col_add_fstr(pinfo->cinfo, COL_INFO, "Fragmented %s NPDU %s(off=%u)",
pdu_type_string, flag_string, segment_offset);
/* As we haven't reassembled anything, we haven't changed "pi", so
we don't have to restore it. */
call_dissector(data_handle, tvb_new_subset_remaining(tvb, offset), pinfo,
tree);
pinfo->fragmented = save_fragmented;
return;
}
if (tvb_offset_exists(tvb, offset)) {
switch (cnf_type & CNF_TYPE) {
case DT_NPDU:
case MD_NPDU:
/* Continue with COTP if any data.
XXX - if this isn't the first Derived PDU of a segmented Initial
PDU, skip that? */
if (nsel == (guchar)tp_nsap_selector || always_decode_transport) {
if (call_dissector(ositp_handle, next_tvb, pinfo, tree) != 0) {
pinfo->fragmented = save_fragmented;
return; /* yes, it appears to be COTP or CLTP */
}
}
if (dissector_try_heuristic(clnp_heur_subdissector_list, next_tvb,
pinfo, tree)) {
pinfo->fragmented = save_fragmented;
return; /* yes, it appears to be one of the protocols in the heuristic list */
}
break;
case ER_NPDU:
/* The payload is the header and "none, some, or all of the data
part of the discarded PDU", i.e. it's like an ICMP error;
dissect it as a CLNP PDU. */
col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
next_length = tvb_length_remaining(tvb, offset);
if (next_length != 0) {
/* We have payload; dissect it. */
ti = proto_tree_add_text(clnp_tree, tvb, offset, next_length,
"Discarded PDU");
discpdu_tree = proto_item_add_subtree(ti, ett_clnp_disc_pdu);
/* Save the current value of the "we're inside an error packet"
flag, and set that flag; subdissectors may treat packets
that are the payload of error packets differently from
"real" packets. */
save_in_error_pkt = pinfo->flags.in_error_pkt;
pinfo->flags.in_error_pkt = TRUE;
call_dissector(clnp_handle, next_tvb, pinfo, discpdu_tree);
/* Restore the "we're inside an error packet" flag. */
pinfo->flags.in_error_pkt = save_in_error_pkt;
}
pinfo->fragmented = save_fragmented;
return; /* we're done with this PDU */
case ERQ_NPDU:
case ERP_NPDU:
/* XXX - dissect this */
break;
}
}
col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
call_dissector(data_handle,next_tvb, pinfo, tree);
pinfo->fragmented = save_fragmented;
} /* dissect_clnp */
