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# t38.cnf
# T.38 conformation file
# 2007 Tomas Kukosa
#.EXPORTS ONLY_VALS WS_DLL
Type-of-msg/t30-indicator
Type-of-msg/t30-data
#.END
#.TYPE_RENAME
Type-of-msg/t30-indicator T30_indicator
Type-of-msg/t30-data T30_data
#.END
#.PDU
IFPPacket
UDPTLPacket
#.END
#.FN_PARS Type-of-msg VAL_PTR=&Type_of_msg_value
#.FN_FTR Type-of-msg
/* info for tap */
if (primary_part)
t38_info->type_msg = Type_of_msg_value;
#.END
#.FN_PARS Type-of-msg/t30-indicator VAL_PTR=&T30ind_value
#.FN_FTR Type-of-msg/t30-indicator
if (primary_part){
col_append_fstr(actx->pinfo->cinfo, COL_INFO, " t30ind: %s",
val_to_str_const(T30ind_value,t38_T30_indicator_vals,"<unknown>"));
}
/* info for tap */
if (primary_part)
t38_info->t30ind_value = T30ind_value;
#.END
#.FN_PARS Type-of-msg/t30-data VAL_PTR=&Data_value
#.FN_FTR Type-of-msg/t30-data
if (primary_part){
col_append_fstr(actx->pinfo->cinfo, COL_INFO, " data:%s:",
val_to_str_const(Data_value,t38_T30_data_vals,"<unknown>"));
}
/* info for tap */
if (primary_part)
t38_info->data_value = Data_value;
#.END
#.FN_FTR Data-Field/_item
if (primary_part) Data_Field_item_num++;
#.END
#.FN_PARS Data-Field/_item/field-type
EXT=(use_pre_corrigendum_asn1_specification)?false:true
EXT_NUM=(use_pre_corrigendum_asn1_specification)?0:4
VAL_PTR=&Data_Field_field_type_value
#.FN_FTR Data-Field/_item/field-type
if (primary_part){
col_append_fstr(actx->pinfo->cinfo, COL_INFO, " %s",
val_to_str_const(Data_Field_field_type_value,t38_T_field_type_vals,"<unknown>"));
}
if (primary_part) {
if (Data_Field_field_type_value == 2 || Data_Field_field_type_value == 4 || Data_Field_field_type_value == 7) {/* hdlc-fcs-OK or hdlc-fcs-OK-sig-end or t4-non-ecm-sig-end*/
fragment_head *frag_msg = NULL;
tvbuff_t* new_tvb = NULL;
bool save_fragmented = actx->pinfo->fragmented;
actx->pinfo->fragmented = true;
/* if reass_start_seqnum=-1 it means we have received the end of the fragmente, without received any fragment data */
if (p_t38_packet_conv_info->reass_start_seqnum != -1) {
uint32_t frag_seq_num;
if (seq_number == (uint32_t)p_t38_packet_conv_info->reass_start_seqnum) {
frag_seq_num = (uint32_t)p_t38_packet_conv_info->additional_hdlc_data_field_counter + Data_Field_item_num - p_t38_packet_conv_info->reass_start_data_field;
} else {
frag_seq_num = seq_number - (uint32_t)p_t38_packet_conv_info->reass_start_seqnum + (uint32_t)p_t38_packet_conv_info->additional_hdlc_data_field_counter + Data_Field_item_num;
}
frag_msg = fragment_add_seq(&data_reassembly_table, /* reassembly table */
tvb, offset, actx->pinfo,
p_t38_packet_conv_info->reass_ID, /* ID for fragments belonging together */
NULL,
frag_seq_num, /* fragment sequence number */
/*0,*/
0, /* fragment length */
false, /* More fragments */
0);
if ( Data_Field_field_type_value == 7 ) {
/* if there was packet lost or other errors during the defrag then frag_msg is NULL. This could also means
* there are out of order packets (e.g, got the tail frame t4-non-ecm-sig-end before the last fragment),
* but we will assume there was packet lost instead, which is more usual. So, we are going to reassemble the packet
* and get some stat, like packet lost and burst number of packet lost
*/
if (!frag_msg) {
force_reassemble_seq(&data_reassembly_table, /* reassembly table */
actx->pinfo,
p_t38_packet_conv_info->reass_ID /* ID for fragments belonging together */
);
} else {
col_append_str(actx->pinfo->cinfo, COL_INFO, " (t4-data Reassembled: No packet lost)");
snprintf(t38_info->desc_comment, MAX_T38_DESC, "No packet lost");
}
if (p_t38_packet_conv_info->packet_lost) {
snprintf(t38_info->desc_comment, MAX_T38_DESC, " Pack lost: %d, Pack burst lost: %d", p_t38_packet_conv_info->packet_lost, p_t38_packet_conv_info->burst_lost);
} else {
snprintf(t38_info->desc_comment, MAX_T38_DESC, "No packet lost");
}
process_reassembled_data(tvb, offset, actx->pinfo,
"Reassembled T38", frag_msg, &data_frag_items, NULL, tree);
/* Now reset fragmentation information in pinfo */
actx->pinfo->fragmented = save_fragmented;
t38_info->time_first_t4_data = p_t38_packet_conv_info->time_first_t4_data;
t38_info->frame_num_first_t4_data = p_t38_packet_conv_info->reass_ID; /* The reass_ID is the Frame number of the first t4 fragment */
} else {
new_tvb = process_reassembled_data(tvb, offset, actx->pinfo,
"Reassembled T38", frag_msg, &data_frag_items, NULL, tree);
/* Now reset fragmentation information in pinfo */
actx->pinfo->fragmented = save_fragmented;
if (new_tvb) call_dissector_with_data((t30_hdlc_handle) ? t30_hdlc_handle : data_handle, new_tvb, actx->pinfo, tree, t38_info);
}
} else {
/* If this is the same sequence number as the previous packet
* (i.e., a retransmission), we don't expect to have any
* fragment data (we reassembled it in the previous packet).
*/
if (p_t38_packet_conv && ((int32_t) seq_number != p_t38_packet_conv_info->last_seqnum)) {
proto_tree_add_expert_format(tree, actx->pinfo, &ei_t38_malformed, tvb, offset, tvb_reported_length_remaining(tvb, offset),
"[RECEIVED END OF FRAGMENT W/OUT ANY FRAGMENT DATA]");
col_append_str(actx->pinfo->cinfo, COL_INFO, " [Malformed?]");
}
actx->pinfo->fragmented = save_fragmented;
}
}
/* reset the reassemble ID and the start seq number if it is not HDLC data */
if ( p_t38_conv && ( ((Data_Field_field_type_value >0) && (Data_Field_field_type_value <6)) || (Data_Field_field_type_value == 7) ) ){
p_t38_conv_info->reass_ID = 0;
p_t38_conv_info->reass_start_seqnum = -1;
p_t38_conv_info->additional_hdlc_data_field_counter = 0;
p_t38_conv_info->seqnum_prev_data_field = -1;
if (p_t38_packet_conv_info->next == NULL) {
p_t38_packet_conv_info->next = wmem_new(wmem_file_scope(), t38_conv_info);
p_t38_packet_conv_info = p_t38_packet_conv_info->next;
memcpy(p_t38_packet_conv_info, p_t38_conv_info, sizeof(t38_conv_info));
}
}
t38_info->Data_Field_field_type_value = Data_Field_field_type_value;
}
#.END
#.FN_BODY Data-Field/_item/field-data VAL_PTR=&value_tvb
tvbuff_t *value_tvb = NULL;
uint32_t value_len;
%(DEFAULT_BODY)s
value_len = tvb_reported_length(value_tvb);
#.FN_FTR Data-Field/_item/field-data
if (primary_part){
if(value_len < 8){
col_append_fstr(actx->pinfo->cinfo, COL_INFO, "[%s]",
tvb_bytes_to_str(actx->pinfo->pool, value_tvb,0,value_len));
}
else {
col_append_fstr(actx->pinfo->cinfo, COL_INFO, "[%s...]",
tvb_bytes_to_str(actx->pinfo->pool, value_tvb,0,7));
}
}
if (primary_part) {
fragment_head *frag_msg = NULL;
/* HDLC Data or t4-non-ecm-data */
if (Data_Field_field_type_value == 0 || Data_Field_field_type_value == 6) { /* 0=HDLC Data or 6=t4-non-ecm-data*/
bool save_fragmented = actx->pinfo->fragmented;
actx->pinfo->fragmented = true;
/* if we have not reassembled this packet and it is the first fragment, reset the reassemble ID and the start seq number*/
if (p_t38_packet_conv && p_t38_conv && (p_t38_packet_conv_info->reass_start_seqnum == -1)) {
/* we use the first fragment's frame_number as fragment ID because the protocol doesn't provide it */
/* XXX: We'd be better off assigning our own IDs using a one-up
* counter, if it's possible for more than one reassembly to
* begin in the same frame.
*/
p_t38_conv_info->reass_ID = actx->pinfo->num;
p_t38_conv_info->reass_start_seqnum = seq_number;
p_t38_conv_info->time_first_t4_data = nstime_to_sec(&actx->pinfo->rel_ts);
p_t38_conv_info->additional_hdlc_data_field_counter = 0;
p_t38_packet_conv_info->reass_ID = p_t38_conv_info->reass_ID;
p_t38_packet_conv_info->reass_start_seqnum = p_t38_conv_info->reass_start_seqnum;
p_t38_packet_conv_info->reass_start_data_field = Data_Field_item_num;
p_t38_packet_conv_info->seqnum_prev_data_field = p_t38_conv_info->seqnum_prev_data_field;
p_t38_packet_conv_info->additional_hdlc_data_field_counter = p_t38_conv_info->additional_hdlc_data_field_counter;
p_t38_packet_conv_info->time_first_t4_data = p_t38_conv_info->time_first_t4_data;
}
if (seq_number == (uint32_t)p_t38_packet_conv_info->seqnum_prev_data_field){
if(p_t38_conv){
p_t38_conv_info->additional_hdlc_data_field_counter++;
}
}
uint32_t frag_seq_num;
if (seq_number == (uint32_t)p_t38_packet_conv_info->reass_start_seqnum) {
frag_seq_num = (uint32_t)p_t38_packet_conv_info->additional_hdlc_data_field_counter + Data_Field_item_num - (uint32_t)p_t38_packet_conv_info->reass_start_data_field;
} else {
frag_seq_num = seq_number - (uint32_t)p_t38_packet_conv_info->reass_start_seqnum + (uint32_t)p_t38_packet_conv_info->additional_hdlc_data_field_counter + Data_Field_item_num;
}
frag_msg = fragment_add_seq(&data_reassembly_table,
value_tvb, 0,
actx->pinfo,
p_t38_packet_conv_info->reass_ID, /* ID for fragments belonging together */
NULL,
frag_seq_num, /* fragment sequence number */
value_len, /* fragment length */
true, /* More fragments */
0);
p_t38_packet_conv_info->seqnum_prev_data_field = (int32_t)seq_number;
process_reassembled_data(tvb, offset, actx->pinfo,
"Reassembled T38", frag_msg, &data_frag_items, NULL, tree);
if (!frag_msg) { /* Not last packet of reassembled */
if (Data_Field_field_type_value == 0) {
col_append_fstr(actx->pinfo->cinfo, COL_INFO," (HDLC fragment %u)", frag_seq_num);
} else {
col_append_fstr(actx->pinfo->cinfo, COL_INFO," (t4-data fragment %u)", seq_number - (uint32_t)p_t38_packet_conv_info->reass_start_seqnum);
}
}
/* Now reset fragmentation information in pinfo */
actx->pinfo->fragmented = save_fragmented;
}
}
#.END
#.FN_HDR UDPTLPacket
/* Initialize to something else than data type */
Data_Field_field_type_value = 1;
#.END
#.FN_PARS UDPTLPacket/seq-number VAL_PTR=&seq_number
#.FN_FTR UDPTLPacket/seq-number
/* info for tap */
if (primary_part)
t38_info->seq_num = seq_number;
col_append_fstr(actx->pinfo->cinfo, COL_INFO, "Seq=%05u ",seq_number);
#.END
#.FN_HDR UDPTLPacket/primary-ifp-packet
primary_part = true;
#.FN_FTR UDPTLPacket/primary-ifp-packet
/* if is a valid t38 packet, add to tap */
/* Note that t4-non-ecm-sig-end without first_t4_data is not valid */
if (p_t38_packet_conv && (!actx->pinfo->flags.in_error_pkt) && ((int32_t) seq_number != p_t38_packet_conv_info->last_seqnum) &&
!(t38_info->type_msg == 1 && t38_info->Data_Field_field_type_value == 7 && t38_info->frame_num_first_t4_data == 0))
tap_queue_packet(t38_tap, actx->pinfo, t38_info);
if (p_t38_conv) p_t38_conv_info->last_seqnum = (int32_t) seq_number;
#.END
#.FN_HDR UDPTLPacket/error-recovery
primary_part = false;
#.FN_FTR UDPTLPacket/error-recovery
primary_part = true;
#.END
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