Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1408 insertions, 0 deletions

diff --git a/epan/dissectors/packet-t38.c b/epan/dissectors/packet-t38.c
new file mode 100644
index 00000000..45127cde
--- /dev/null
+++ b/epan/dissectors/packet-t38.c
@@ -0,0 +1,1408 @@
+/* Do not modify this file. Changes will be overwritten.                      */
+/* Generated automatically by the ASN.1 to Wireshark dissector compiler       */
+/* packet-t38.c                                                               */
+/* asn2wrs.py -L -p t38 -c ./t38.cnf -s ./packet-t38-template -D . -O ../.. T38_2002.asn */
+
+/* packet-t38.c
+ * Routines for T.38 packet dissection
+ * 2003  Hans Viens
+ * 2004  Alejandro Vaquero, add support Conversations for SDP
+ * 2006  Alejandro Vaquero, add T30 reassemble and dissection
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+
+/* Depending on what ASN.1 specification is used you may have to change
+ * the preference setting regarding Pre-Corrigendum ASN.1 specification:
+ * http://www.itu.int/ITU-T/asn1/database/itu-t/t/t38/1998/T38.html  (Pre-Corrigendum=TRUE)
+ * http://www.itu.int/ITU-T/asn1/database/itu-t/t/t38/2003/T38(1998).html (Pre-Corrigendum=TRUE)
+ *
+ * http://www.itu.int/ITU-T/asn1/database/itu-t/t/t38/2003/T38(2002).html (Pre-Corrigendum=FALSE)
+ * http://www.itu.int/ITU-T/asn1/database/itu-t/t/t38/2002/t38.html  (Pre-Corrigendum=FALSE)
+ * http://www.itu.int/ITU-T/asn1/database/itu-t/t/t38/2002-Amd1/T38.html (Pre-Corrigendum=FALSE)
+ */
+
+/* TO DO:
+ * - TCP desegmentation is currently not supported for T.38 IFP directly over TCP.
+ * - H.245 dissectors should be updated to start conversations for T.38 similar to RTP.
+ * - Sometimes the last octet is not high-lighted when selecting something in the tree. Bug in PER dissector?
+ * - Add support for RTP payload audio/t38 (draft-jones-avt-audio-t38-03.txt), i.e. T38 in RTP packets.
+ */
+
+
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/reassemble.h>
+#include <epan/conversation.h>
+#include <epan/tap.h>
+#include <epan/expert.h>
+#include <epan/strutil.h>
+#include <epan/prefs.h>
+#include <epan/ipproto.h>
+#include <epan/asn1.h>
+#include <epan/proto_data.h>
+
+#include "packet-t38.h"
+#include "packet-per.h"
+#include "packet-tpkt.h"
+#include "packet-acdr.h"
+
+void proto_register_t38(void);
+
+static int t38_tap = -1;
+
+/* dissect using the Pre Corrigendum T.38 ASN.1 specification (1998) */
+static gboolean use_pre_corrigendum_asn1_specification = TRUE;
+
+/* dissect packets that looks like RTP version 2 packets as RTP     */
+/* instead of as T.38. This may result in that some T.38 UPTL       */
+/* packets with sequence number values higher than 32767 may be     */
+/* shown as RTP packets.                                            */
+static gboolean dissect_possible_rtpv2_packets_as_rtp = FALSE;
+
+
+/* Reassembly of T.38 PDUs over TPKT over TCP */
+static gboolean t38_tpkt_reassembly = TRUE;
+
+/* Preference setting whether TPKT header is used when sending T.38 over TCP.
+ * The default setting is Maybe where the dissector will look on the first
+ * bytes to try to determine whether TPKT header is used or not. This may not
+ * work so well in some cases. You may want to change the setting to Always or
+ * Newer.
+ */
+#define T38_TPKT_NEVER 0   /* Assume that there is never a TPKT header    */
+#define T38_TPKT_ALWAYS 1  /* Assume that there is always a TPKT header   */
+#define T38_TPKT_MAYBE 2   /* Assume TPKT if first octets are 03-00-xx-xx */
+static gint t38_tpkt_usage = T38_TPKT_MAYBE;
+
+static const enum_val_t t38_tpkt_options[] = {
+  {"never", "Never", T38_TPKT_NEVER},
+  {"always", "Always", T38_TPKT_ALWAYS},
+  {"maybe", "Maybe", T38_TPKT_MAYBE},
+  {NULL, NULL, -1}
+};
+
+
+
+/* T38 */
+static dissector_handle_t t38_udp_handle;
+static dissector_handle_t t38_tcp_handle;
+static dissector_handle_t t38_tcp_pdu_handle;
+static dissector_handle_t rtp_handle;
+static dissector_handle_t t30_hdlc_handle;
+static dissector_handle_t data_handle;
+
+static gint32 Type_of_msg_value;
+static guint32 Data_Field_field_type_value;
+static guint32 Data_value;
+static guint32 T30ind_value;
+static guint32 Data_Field_item_num;
+
+static int proto_t38 = -1;
+static int proto_acdr = -1;
+static int hf_t38_IFPPacket_PDU = -1;             /* IFPPacket */
+static int hf_t38_UDPTLPacket_PDU = -1;           /* UDPTLPacket */
+static int hf_t38_type_of_msg = -1;               /* Type_of_msg */
+static int hf_t38_data_field = -1;                /* Data_Field */
+static int hf_t38_t30_indicator = -1;             /* T30_indicator */
+static int hf_t38_t30_data = -1;                  /* T30_data */
+static int hf_t38_Data_Field_item = -1;           /* Data_Field_item */
+static int hf_t38_field_type = -1;                /* T_field_type */
+static int hf_t38_field_data = -1;                /* T_field_data */
+static int hf_t38_seq_number = -1;                /* T_seq_number */
+static int hf_t38_primary_ifp_packet = -1;        /* T_primary_ifp_packet */
+static int hf_t38_error_recovery = -1;            /* T_error_recovery */
+static int hf_t38_secondary_ifp_packets = -1;     /* T_secondary_ifp_packets */
+static int hf_t38_secondary_ifp_packets_item = -1;  /* OpenType_IFPPacket */
+static int hf_t38_fec_info = -1;                  /* T_fec_info */
+static int hf_t38_fec_npackets = -1;              /* INTEGER */
+static int hf_t38_fec_data = -1;                  /* T_fec_data */
+static int hf_t38_fec_data_item = -1;             /* OCTET_STRING */
+
+/* T38 setup fields */
+static int hf_t38_setup        = -1;
+static int hf_t38_setup_frame  = -1;
+static int hf_t38_setup_method = -1;
+
+/* T38 Data reassemble fields */
+static int hf_t38_fragments = -1;
+static int hf_t38_fragment = -1;
+static int hf_t38_fragment_overlap = -1;
+static int hf_t38_fragment_overlap_conflicts = -1;
+static int hf_t38_fragment_multiple_tails = -1;
+static int hf_t38_fragment_too_long_fragment = -1;
+static int hf_t38_fragment_error = -1;
+static int hf_t38_fragment_count = -1;
+static int hf_t38_reassembled_in = -1;
+static int hf_t38_reassembled_length = -1;
+
+static gint ett_t38 = -1;
+static gint ett_t38_IFPPacket = -1;
+static gint ett_t38_Type_of_msg = -1;
+static gint ett_t38_Data_Field = -1;
+static gint ett_t38_Data_Field_item = -1;
+static gint ett_t38_UDPTLPacket = -1;
+static gint ett_t38_T_error_recovery = -1;
+static gint ett_t38_T_secondary_ifp_packets = -1;
+static gint ett_t38_T_fec_info = -1;
+static gint ett_t38_T_fec_data = -1;
+static gint ett_t38_setup = -1;
+
+static gint ett_data_fragment = -1;
+static gint ett_data_fragments = -1;
+
+static expert_field ei_t38_malformed = EI_INIT;
+
+static gboolean primary_part = TRUE;
+static guint32 seq_number = 0;
+
+/* Tables for reassembly of Data fragments. */
+static reassembly_table data_reassembly_table;
+
+static const fragment_items data_frag_items = {
+	/* Fragment subtrees */
+	&ett_data_fragment,
+	&ett_data_fragments,
+	/* Fragment fields */
+	&hf_t38_fragments,
+	&hf_t38_fragment,
+	&hf_t38_fragment_overlap,
+	&hf_t38_fragment_overlap_conflicts,
+	&hf_t38_fragment_multiple_tails,
+	&hf_t38_fragment_too_long_fragment,
+	&hf_t38_fragment_error,
+	&hf_t38_fragment_count,
+	/* Reassembled in field */
+	&hf_t38_reassembled_in,
+	/* Reassembled length field */
+	&hf_t38_reassembled_length,
+	/* Reassembled data field */
+	NULL,
+	/* Tag */
+	"Data fragments"
+};
+
+typedef struct _fragment_key {
+	address src;
+	address dst;
+	guint32	id;
+} fragment_key;
+
+static conversation_t *p_conv= NULL;
+static t38_conv *p_t38_conv = NULL;
+static t38_conv *p_t38_packet_conv = NULL;
+static t38_conv_info *p_t38_conv_info = NULL;
+static t38_conv_info *p_t38_packet_conv_info = NULL;
+
+/* RTP Version is the first 2 bits of the first octet in the UDP payload*/
+#define RTP_VERSION(octet)	((octet) >> 6)
+
+void proto_reg_handoff_t38(void);
+
+static void show_setup_info(tvbuff_t *tvb, proto_tree *tree, t38_conv *p_t38_conv);
+/* Preferences bool to control whether or not setup info should be shown */
+static gboolean global_t38_show_setup_info = TRUE;
+
+/* Can tap up to 4 T38 packets within same packet */
+/* We only tap the primary part, not the redundancy */
+#define MAX_T38_MESSAGES_IN_PACKET 4
+static t38_packet_info t38_info_arr[MAX_T38_MESSAGES_IN_PACKET];
+static int t38_info_current=0;
+static t38_packet_info *t38_info=NULL;
+
+
+/* Set up an T38 conversation */
+void t38_add_address(packet_info *pinfo,
+                     address *addr, int port,
+                     int other_port,
+                     const gchar *setup_method, guint32 setup_frame_number)
+{
+        address null_addr;
+        conversation_t* p_conversation;
+        t38_conv* p_conversation_data = NULL;
+
+        /*
+         * If this isn't the first time this packet has been processed,
+         * we've already done this work, so we don't need to do it
+         * again.
+         */
+        if ((pinfo->fd->visited) || (t38_udp_handle == NULL))
+        {
+                return;
+        }
+
+        clear_address(&null_addr);
+
+        /*
+         * Check if the ip address and port combination is not
+         * already registered as a conversation.
+         */
+        p_conversation = find_conversation( setup_frame_number, addr, &null_addr, CONVERSATION_UDP, port, other_port,
+                                NO_ADDR_B | (!other_port ? NO_PORT_B : 0));
+
+        /*
+         * If not, create a new conversation.
+         */
+        if ( !p_conversation || p_conversation->setup_frame != setup_frame_number) {
+                p_conversation = conversation_new( setup_frame_number, addr, &null_addr, CONVERSATION_UDP,
+                                           (guint32)port, (guint32)other_port,
+                                                                   NO_ADDR2 | (!other_port ? NO_PORT2 : 0));
+        }
+
+        /* Set dissector */
+        conversation_set_dissector(p_conversation, t38_udp_handle);
+
+        /*
+         * Check if the conversation has data associated with it.
+         */
+        p_conversation_data = (t38_conv*)conversation_get_proto_data(p_conversation, proto_t38);
+
+        /*
+         * If not, add a new data item.
+         */
+        if ( ! p_conversation_data ) {
+                /* Create conversation data */
+                p_conversation_data = wmem_new(wmem_file_scope(), t38_conv);
+
+                conversation_add_proto_data(p_conversation, proto_t38, p_conversation_data);
+        }
+
+        /*
+         * Update the conversation data.
+         */
+        (void) g_strlcpy(p_conversation_data->setup_method, setup_method, MAX_T38_SETUP_METHOD_SIZE);
+        p_conversation_data->setup_frame_number = setup_frame_number;
+        p_conversation_data->src_t38_info.reass_ID = 0;
+        p_conversation_data->src_t38_info.reass_start_seqnum = -1;
+        p_conversation_data->src_t38_info.reass_data_type = 0;
+        p_conversation_data->src_t38_info.last_seqnum = -1;
+        p_conversation_data->src_t38_info.packet_lost = 0;
+        p_conversation_data->src_t38_info.burst_lost = 0;
+        p_conversation_data->src_t38_info.time_first_t4_data = 0;
+        p_conversation_data->src_t38_info.additional_hdlc_data_field_counter = 0;
+        p_conversation_data->src_t38_info.seqnum_prev_data_field = -1;
+        p_conversation_data->src_t38_info.next = NULL;
+
+        p_conversation_data->dst_t38_info.reass_ID = 0;
+        p_conversation_data->dst_t38_info.reass_start_seqnum = -1;
+        p_conversation_data->dst_t38_info.reass_data_type = 0;
+        p_conversation_data->dst_t38_info.last_seqnum = -1;
+        p_conversation_data->dst_t38_info.packet_lost = 0;
+        p_conversation_data->dst_t38_info.burst_lost = 0;
+        p_conversation_data->dst_t38_info.time_first_t4_data = 0;
+        p_conversation_data->dst_t38_info.additional_hdlc_data_field_counter = 0;
+        p_conversation_data->dst_t38_info.seqnum_prev_data_field = -1;
+        p_conversation_data->dst_t38_info.next = NULL;
+}
+
+
+static fragment_head *
+force_reassemble_seq(reassembly_table *table, packet_info *pinfo, guint32 id)
+{
+	fragment_head *fd_head;
+	fragment_item *fd_i;
+	fragment_item *last_fd;
+	guint32 dfpos, size, packet_lost, burst_lost, seq_num;
+	guint8 *data;
+
+	fd_head = fragment_get(table, pinfo, id, NULL);
+
+	/* have we already seen this frame ?*/
+	if (pinfo->fd->visited) {
+		if (fd_head != NULL && fd_head->flags & FD_DEFRAGMENTED) {
+			return fd_head;
+		} else {
+			return NULL;
+		}
+	}
+
+	if (fd_head==NULL){
+		/* we must have it to continue */
+		return NULL;
+	}
+
+	/* check for packet lost and count the burst of packet lost */
+	packet_lost = 0;
+	burst_lost = 0;
+	seq_num = 0;
+	for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
+		if (seq_num != fd_i->offset) {
+			packet_lost += fd_i->offset - seq_num;
+			if ( (fd_i->offset - seq_num) > burst_lost ) {
+				burst_lost = fd_i->offset - seq_num;
+			}
+		}
+		seq_num = fd_i->offset + 1;
+	}
+
+	/* we have received an entire packet, defragment it and
+	 * free all fragments
+	 */
+	size=0;
+	last_fd=NULL;
+	for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
+	  if(!last_fd || last_fd->offset!=fd_i->offset){
+	    size+=fd_i->len;
+	  }
+	  last_fd=fd_i;
+	}
+
+	data = (guint8 *) wmem_alloc(pinfo->pool, size);
+	fd_head->tvb_data = tvb_new_real_data(data, size, size);
+	fd_head->len = size;		/* record size for caller	*/
+
+	/* add all data fragments */
+	dfpos = 0;
+	last_fd=NULL;
+	for (fd_i=fd_head->next;fd_i && fd_i->len + dfpos <= size;fd_i=fd_i->next) {
+	  if (fd_i->len) {
+	    if(!last_fd || last_fd->offset!=fd_i->offset){
+	      tvb_memcpy(fd_i->tvb_data, data+dfpos, 0, fd_i->len);
+	      dfpos += fd_i->len;
+	    } else {
+	      /* duplicate/retransmission/overlap */
+	      fd_i->flags    |= FD_OVERLAP;
+	      fd_head->flags |= FD_OVERLAP;
+	      if( (last_fd->len!=fd_i->len)
+		  || tvb_memeql(last_fd->tvb_data, 0, tvb_get_ptr(fd_i->tvb_data, 0, last_fd->len), last_fd->len) ){
+			fd_i->flags    |= FD_OVERLAPCONFLICT;
+			fd_head->flags |= FD_OVERLAPCONFLICT;
+	      }
+	    }
+	  }
+	  last_fd=fd_i;
+	}
+
+	/* we have defragmented the pdu, now free all fragments*/
+	for (fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
+	  if(fd_i->tvb_data){
+	    tvb_free(fd_i->tvb_data);
+	    fd_i->tvb_data=NULL;
+	  }
+	}
+
+	/* mark this packet as defragmented */
+	fd_head->flags |= FD_DEFRAGMENTED;
+	fd_head->reassembled_in=pinfo->num;
+
+	col_append_fstr(pinfo->cinfo, COL_INFO, " (t4-data Reassembled: %d pack lost, %d pack burst lost)", packet_lost, burst_lost);
+
+	p_t38_packet_conv_info->packet_lost = packet_lost;
+	p_t38_packet_conv_info->burst_lost = burst_lost;
+
+	return fd_head;
+}
+
+/* T38 Routines */
+
+const value_string t38_T30_indicator_vals[] = {
+  {   0, "no-signal" },
+  {   1, "cng" },
+  {   2, "ced" },
+  {   3, "v21-preamble" },
+  {   4, "v27-2400-training" },
+  {   5, "v27-4800-training" },
+  {   6, "v29-7200-training" },
+  {   7, "v29-9600-training" },
+  {   8, "v17-7200-short-training" },
+  {   9, "v17-7200-long-training" },
+  {  10, "v17-9600-short-training" },
+  {  11, "v17-9600-long-training" },
+  {  12, "v17-12000-short-training" },
+  {  13, "v17-12000-long-training" },
+  {  14, "v17-14400-short-training" },
+  {  15, "v17-14400-long-training" },
+  {  16, "v8-ansam" },
+  {  17, "v8-signal" },
+  {  18, "v34-cntl-channel-1200" },
+  {  19, "v34-pri-channel" },
+  {  20, "v34-CC-retrain" },
+  {  21, "v33-12000-training" },
+  {  22, "v33-14400-training" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_t38_T30_indicator(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
+                                     16, &T30ind_value, TRUE, 7, NULL);
+
+    if (primary_part){
+        col_append_fstr(actx->pinfo->cinfo, COL_INFO, " t30ind: %s",
+         val_to_str(T30ind_value,t38_T30_indicator_vals,"<unknown>"));
+    }
+
+    /* info for tap */
+    if (primary_part)
+        t38_info->t30ind_value = T30ind_value;
+  return offset;
+}
+
+
+const value_string t38_T30_data_vals[] = {
+  {   0, "v21" },
+  {   1, "v27-2400" },
+  {   2, "v27-4800" },
+  {   3, "v29-7200" },
+  {   4, "v29-9600" },
+  {   5, "v17-7200" },
+  {   6, "v17-9600" },
+  {   7, "v17-12000" },
+  {   8, "v17-14400" },
+  {   9, "v8" },
+  {  10, "v34-pri-rate" },
+  {  11, "v34-CC-1200" },
+  {  12, "v34-pri-ch" },
+  {  13, "v33-12000" },
+  {  14, "v33-14400" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_t38_T30_data(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
+                                     9, &Data_value, TRUE, 6, NULL);
+
+    if (primary_part){
+        col_append_fstr(actx->pinfo->cinfo, COL_INFO, " data:%s:",
+         val_to_str(Data_value,t38_T30_data_vals,"<unknown>"));
+    }
+
+
+    /* info for tap */
+    if (primary_part)
+        t38_info->data_value = Data_value;
+  return offset;
+}
+
+
+static const value_string t38_Type_of_msg_vals[] = {
+  {   0, "t30-indicator" },
+  {   1, "t30-data" },
+  { 0, NULL }
+};
+
+static const per_choice_t Type_of_msg_choice[] = {
+  {   0, &hf_t38_t30_indicator   , ASN1_NO_EXTENSIONS     , dissect_t38_T30_indicator },
+  {   1, &hf_t38_t30_data        , ASN1_NO_EXTENSIONS     , dissect_t38_T30_data },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_t38_Type_of_msg(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_choice(tvb, offset, actx, tree, hf_index,
+                                 ett_t38_Type_of_msg, Type_of_msg_choice,
+                                 &Type_of_msg_value);
+
+  /* info for tap */
+  if (primary_part)
+    t38_info->type_msg = Type_of_msg_value;
+  return offset;
+}
+
+
+static const value_string t38_T_field_type_vals[] = {
+  {   0, "hdlc-data" },
+  {   1, "hdlc-sig-end" },
+  {   2, "hdlc-fcs-OK" },
+  {   3, "hdlc-fcs-BAD" },
+  {   4, "hdlc-fcs-OK-sig-end" },
+  {   5, "hdlc-fcs-BAD-sig-end" },
+  {   6, "t4-non-ecm-data" },
+  {   7, "t4-non-ecm-sig-end" },
+  {   8, "cm-message" },
+  {   9, "jm-message" },
+  {  10, "ci-message" },
+  {  11, "v34rate" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_t38_T_field_type(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_enumerated(tvb, offset, actx, tree, hf_index,
+                                     8, &Data_Field_field_type_value, (use_pre_corrigendum_asn1_specification)?FALSE:TRUE, (use_pre_corrigendum_asn1_specification)?0:4, NULL);
+
+    if (primary_part){
+        col_append_fstr(actx->pinfo->cinfo, COL_INFO, " %s",
+         val_to_str(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;
+            gboolean 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) {
+                guint32 frag_seq_num;
+                if (seq_number == (guint32)p_t38_packet_conv_info->reass_start_seqnum) {
+                    frag_seq_num = (guint32)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 - (guint32)p_t38_packet_conv_info->reass_start_seqnum + (guint32)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 && ((gint32) 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;
+    }
+  return offset;
+}
+
+
+
+static int
+dissect_t38_T_field_data(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+    tvbuff_t *value_tvb = NULL;
+    guint32 value_len;
+
+  offset = dissect_per_octet_string(tvb, offset, actx, tree, hf_index,
+                                       1, 65535, FALSE, &value_tvb);
+
+    value_len = tvb_reported_length(value_tvb);
+
+
+    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*/
+            gboolean 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 == (guint32)p_t38_packet_conv_info->seqnum_prev_data_field){
+                   if(p_t38_conv){
+                     p_t38_conv_info->additional_hdlc_data_field_counter++;
+                   }
+	    }
+            guint32 frag_seq_num;
+            if (seq_number == (guint32)p_t38_packet_conv_info->reass_start_seqnum) {
+                frag_seq_num = (guint32)p_t38_packet_conv_info->additional_hdlc_data_field_counter + Data_Field_item_num - (guint32)p_t38_packet_conv_info->reass_start_data_field;
+            } else {
+                frag_seq_num = seq_number - (guint32)p_t38_packet_conv_info->reass_start_seqnum + (guint32)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 = (gint32)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 - (guint32)p_t38_packet_conv_info->reass_start_seqnum);
+                }
+            }
+
+            /* Now reset fragmentation information in pinfo */
+            actx->pinfo->fragmented = save_fragmented;
+        }
+    }
+  return offset;
+}
+
+
+static const per_sequence_t Data_Field_item_sequence[] = {
+  { &hf_t38_field_type      , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_T_field_type },
+  { &hf_t38_field_data      , ASN1_NO_EXTENSIONS     , ASN1_OPTIONAL    , dissect_t38_T_field_data },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_t38_Data_Field_item(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
+                                   ett_t38_Data_Field_item, Data_Field_item_sequence);
+
+    if (primary_part) Data_Field_item_num++;
+  return offset;
+}
+
+
+static const per_sequence_t Data_Field_sequence_of[1] = {
+  { &hf_t38_Data_Field_item , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_Data_Field_item },
+};
+
+static int
+dissect_t38_Data_Field(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_sequence_of(tvb, offset, actx, tree, hf_index,
+                                      ett_t38_Data_Field, Data_Field_sequence_of);
+
+  return offset;
+}
+
+
+static const per_sequence_t IFPPacket_sequence[] = {
+  { &hf_t38_type_of_msg     , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_Type_of_msg },
+  { &hf_t38_data_field      , ASN1_NO_EXTENSIONS     , ASN1_OPTIONAL    , dissect_t38_Data_Field },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_t38_IFPPacket(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
+                                   ett_t38_IFPPacket, IFPPacket_sequence);
+
+  return offset;
+}
+
+
+
+static int
+dissect_t38_T_seq_number(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
+                                                            0U, 65535U, &seq_number, FALSE);
+
+    /* info for tap */
+    if (primary_part)
+        t38_info->seq_num = seq_number;
+
+    col_append_fstr(actx->pinfo->cinfo, COL_INFO, "Seq=%05u ",seq_number);
+  return offset;
+}
+
+
+
+static int
+dissect_t38_T_primary_ifp_packet(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+    primary_part = TRUE;
+  offset = dissect_per_open_type(tvb, offset, actx, tree, hf_index, dissect_t38_IFPPacket);
+
+    /* 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) && ((gint32) 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 = (gint32) seq_number;
+  return offset;
+}
+
+
+
+static int
+dissect_t38_OpenType_IFPPacket(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_open_type(tvb, offset, actx, tree, hf_index, dissect_t38_IFPPacket);
+
+  return offset;
+}
+
+
+static const per_sequence_t T_secondary_ifp_packets_sequence_of[1] = {
+  { &hf_t38_secondary_ifp_packets_item, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_OpenType_IFPPacket },
+};
+
+static int
+dissect_t38_T_secondary_ifp_packets(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_sequence_of(tvb, offset, actx, tree, hf_index,
+                                      ett_t38_T_secondary_ifp_packets, T_secondary_ifp_packets_sequence_of);
+
+  return offset;
+}
+
+
+
+static int
+dissect_t38_INTEGER(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_integer(tvb, offset, actx, tree, hf_index, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_t38_OCTET_STRING(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_octet_string(tvb, offset, actx, tree, hf_index,
+                                       NO_BOUND, NO_BOUND, FALSE, NULL);
+
+  return offset;
+}
+
+
+static const per_sequence_t T_fec_data_sequence_of[1] = {
+  { &hf_t38_fec_data_item   , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_OCTET_STRING },
+};
+
+static int
+dissect_t38_T_fec_data(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_sequence_of(tvb, offset, actx, tree, hf_index,
+                                      ett_t38_T_fec_data, T_fec_data_sequence_of);
+
+  return offset;
+}
+
+
+static const per_sequence_t T_fec_info_sequence[] = {
+  { &hf_t38_fec_npackets    , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_INTEGER },
+  { &hf_t38_fec_data        , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_T_fec_data },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_t38_T_fec_info(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
+                                   ett_t38_T_fec_info, T_fec_info_sequence);
+
+  return offset;
+}
+
+
+static const value_string t38_T_error_recovery_vals[] = {
+  {   0, "secondary-ifp-packets" },
+  {   1, "fec-info" },
+  { 0, NULL }
+};
+
+static const per_choice_t T_error_recovery_choice[] = {
+  {   0, &hf_t38_secondary_ifp_packets, ASN1_NO_EXTENSIONS     , dissect_t38_T_secondary_ifp_packets },
+  {   1, &hf_t38_fec_info        , ASN1_NO_EXTENSIONS     , dissect_t38_T_fec_info },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_t38_T_error_recovery(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+    primary_part = FALSE;
+  offset = dissect_per_choice(tvb, offset, actx, tree, hf_index,
+                                 ett_t38_T_error_recovery, T_error_recovery_choice,
+                                 NULL);
+
+    primary_part = TRUE;
+  return offset;
+}
+
+
+static const per_sequence_t UDPTLPacket_sequence[] = {
+  { &hf_t38_seq_number      , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_T_seq_number },
+  { &hf_t38_primary_ifp_packet, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_T_primary_ifp_packet },
+  { &hf_t38_error_recovery  , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_t38_T_error_recovery },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_t38_UDPTLPacket(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+    /* Initialize to something else than data type */
+    Data_Field_field_type_value = 1;
+  offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
+                                   ett_t38_UDPTLPacket, UDPTLPacket_sequence);
+
+  return offset;
+}
+
+/*--- PDUs ---*/
+
+static int dissect_IFPPacket_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_) {
+  int offset = 0;
+  asn1_ctx_t asn1_ctx;
+  asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, TRUE, pinfo);
+  offset = dissect_t38_IFPPacket(tvb, offset, &asn1_ctx, tree, hf_t38_IFPPacket_PDU);
+  offset += 7; offset >>= 3;
+  return offset;
+}
+static int dissect_UDPTLPacket_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_, void *data _U_) {
+  int offset = 0;
+  asn1_ctx_t asn1_ctx;
+  asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, TRUE, pinfo);
+  offset = dissect_t38_UDPTLPacket(tvb, offset, &asn1_ctx, tree, hf_t38_UDPTLPacket_PDU);
+  offset += 7; offset >>= 3;
+  return offset;
+}
+
+
+/* initialize the tap t38_info and the conversation */
+static void
+init_t38_info_conv(packet_info *pinfo)
+{
+	/* tap info */
+	t38_info_current++;
+	if (t38_info_current==MAX_T38_MESSAGES_IN_PACKET) {
+		t38_info_current=0;
+	}
+	t38_info = &t38_info_arr[t38_info_current];
+
+	t38_info->seq_num = 0;
+	t38_info->type_msg = 0;
+	t38_info->data_value = 0;
+	t38_info->t30ind_value =0;
+	t38_info->setup_frame_number = 0;
+	t38_info->Data_Field_field_type_value = 0;
+	t38_info->desc[0] = '\0';
+	t38_info->desc_comment[0] = '\0';
+	t38_info->time_first_t4_data = 0;
+	t38_info->frame_num_first_t4_data = 0;
+
+
+	/*
+		p_t38_packet_conv hold the conversation info in each of the packets.
+		p_t38_conv hold the conversation info used to reassemble the HDLC packets, and also the Setup info (e.g SDP)
+		If we already have p_t38_packet_conv in the packet, it means we already reassembled the HDLC packets, so we don't
+		need to use p_t38_conv
+	*/
+	p_t38_packet_conv = NULL;
+	p_t38_conv = NULL;
+
+	/* Use existing packet info if available */
+	p_t38_packet_conv = (t38_conv *)p_get_proto_data(wmem_file_scope(), pinfo, proto_t38, 0);
+
+
+	/* find the conversation used for Reassemble and Setup Info */
+	p_conv = find_conversation(pinfo->num, &pinfo->net_dst, &pinfo->net_src,
+                                   conversation_pt_to_conversation_type(pinfo->ptype),
+                                   pinfo->destport, pinfo->srcport, NO_ADDR_B | NO_PORT_B);
+
+	/* create a conv if it doen't exist */
+	if (!p_conv) {
+		p_conv = conversation_new(pinfo->num, &pinfo->net_src, &pinfo->net_dst,
+			      conversation_pt_to_conversation_type(pinfo->ptype), pinfo->srcport, pinfo->destport, NO_ADDR2 | NO_PORT2);
+
+		/* Set dissector */
+		conversation_set_dissector(p_conv, t38_udp_handle);
+	}
+
+	p_t38_conv = (t38_conv *)conversation_get_proto_data(p_conv, proto_t38);
+
+	/* create the conversation if it doesn't exist */
+	if (!p_t38_conv) {
+		p_t38_conv = wmem_new(wmem_file_scope(), t38_conv);
+		p_t38_conv->setup_method[0] = '\0';
+		p_t38_conv->setup_frame_number = 0;
+
+		p_t38_conv->src_t38_info.reass_ID = 0;
+		p_t38_conv->src_t38_info.reass_start_seqnum = -1;
+		p_t38_conv->src_t38_info.reass_start_data_field = 0;
+		p_t38_conv->src_t38_info.reass_data_type = 0;
+		p_t38_conv->src_t38_info.last_seqnum = -1;
+		p_t38_conv->src_t38_info.packet_lost = 0;
+		p_t38_conv->src_t38_info.burst_lost = 0;
+		p_t38_conv->src_t38_info.time_first_t4_data = 0;
+		p_t38_conv->src_t38_info.additional_hdlc_data_field_counter = 0;
+		p_t38_conv->src_t38_info.seqnum_prev_data_field = -1;
+		p_t38_conv->src_t38_info.next = NULL;
+
+		p_t38_conv->dst_t38_info.reass_ID = 0;
+		p_t38_conv->dst_t38_info.reass_start_seqnum = -1;
+		p_t38_conv->dst_t38_info.reass_start_data_field = 0;
+		p_t38_conv->dst_t38_info.reass_data_type = 0;
+		p_t38_conv->dst_t38_info.last_seqnum = -1;
+		p_t38_conv->dst_t38_info.packet_lost = 0;
+		p_t38_conv->dst_t38_info.burst_lost = 0;
+		p_t38_conv->dst_t38_info.time_first_t4_data = 0;
+		p_t38_conv->dst_t38_info.additional_hdlc_data_field_counter = 0;
+		p_t38_conv->dst_t38_info.seqnum_prev_data_field = -1;
+		p_t38_conv->dst_t38_info.next = NULL;
+
+		conversation_add_proto_data(p_conv, proto_t38, p_t38_conv);
+	}
+
+	if (!p_t38_packet_conv) {
+		/* copy the t38 conversation info to the packet t38 conversation */
+		p_t38_packet_conv = wmem_new(wmem_file_scope(), t38_conv);
+		(void) g_strlcpy(p_t38_packet_conv->setup_method, p_t38_conv->setup_method, MAX_T38_SETUP_METHOD_SIZE);
+		p_t38_packet_conv->setup_frame_number = p_t38_conv->setup_frame_number;
+
+		memcpy(&(p_t38_packet_conv->src_t38_info), &(p_t38_conv->src_t38_info), sizeof(t38_conv_info));
+		memcpy(&(p_t38_packet_conv->dst_t38_info), &(p_t38_conv->dst_t38_info), sizeof(t38_conv_info));
+
+		p_add_proto_data(wmem_file_scope(), pinfo, proto_t38, 0, p_t38_packet_conv);
+	}
+
+	if (addresses_equal(conversation_key_addr1(p_conv->key_ptr), &pinfo->net_src)) {
+		p_t38_conv_info = &(p_t38_conv->src_t38_info);
+		p_t38_packet_conv_info = &(p_t38_packet_conv->src_t38_info);
+	} else {
+		p_t38_conv_info = &(p_t38_conv->dst_t38_info);
+		p_t38_packet_conv_info = &(p_t38_packet_conv->dst_t38_info);
+	}
+
+	/* update t38_info */
+	t38_info->setup_frame_number = p_t38_packet_conv->setup_frame_number;
+}
+
+/* Entry point for dissection */
+static int
+dissect_t38_udp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+	guint8 octet1;
+	proto_item *it;
+	proto_tree *tr;
+	guint32 offset=0;
+
+	/*
+	 * XXX - heuristic to check for misidentified packets.
+	 */
+	if (dissect_possible_rtpv2_packets_as_rtp){
+		octet1 = tvb_get_guint8(tvb, offset);
+		if (RTP_VERSION(octet1) == 2){
+			return call_dissector(rtp_handle,tvb,pinfo,tree);
+		}
+	}
+
+	col_set_str(pinfo->cinfo, COL_PROTOCOL, "T.38");
+	col_clear(pinfo->cinfo, COL_INFO);
+
+	primary_part = TRUE;
+
+	/* This indicate the item number in the primary part of the T38 message, it is used for the reassemble of T30 packets */
+	Data_Field_item_num = 0;
+
+	it=proto_tree_add_protocol_format(tree, proto_t38, tvb, 0, -1, "ITU-T Recommendation T.38");
+	tr=proto_item_add_subtree(it, ett_t38);
+
+	/* init tap and conv info */
+	init_t38_info_conv(pinfo);
+
+	/* Show Conversation setup info if exists*/
+	if (global_t38_show_setup_info) {
+		show_setup_info(tvb, tr, p_t38_packet_conv);
+	}
+
+	col_append_str(pinfo->cinfo, COL_INFO, "UDP: UDPTLPacket ");
+
+	offset = dissect_UDPTLPacket_PDU(tvb, pinfo, tr, NULL);
+
+	if (tvb_reported_length_remaining(tvb,offset)>0){
+		proto_tree_add_expert_format(tr, pinfo, &ei_t38_malformed, tvb, offset, tvb_reported_length_remaining(tvb, offset),
+				"[MALFORMED PACKET or wrong preference settings]");
+		col_append_str(pinfo->cinfo, COL_INFO, " [Malformed?]");
+	}
+	return tvb_captured_length(tvb);
+}
+
+static int
+dissect_t38_tcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+	proto_item *it;
+	proto_tree *tr;
+	guint32 offset=0;
+        tvbuff_t *next_tvb;
+	guint16 ifp_packet_number=1;
+
+	col_set_str(pinfo->cinfo, COL_PROTOCOL, "T.38");
+	col_clear(pinfo->cinfo, COL_INFO);
+
+	primary_part = TRUE;
+
+	/* This indicate the item number in the primary part of the T38 message, it is used for the reassemble of T30 packets */
+	Data_Field_item_num = 0;
+
+	it=proto_tree_add_protocol_format(tree, proto_t38, tvb, 0, -1, "ITU-T Recommendation T.38");
+	tr=proto_item_add_subtree(it, ett_t38);
+
+	/* init tap and conv info */
+	init_t38_info_conv(pinfo);
+
+	/* Show Conversation setup info if exists*/
+	if (global_t38_show_setup_info) {
+		show_setup_info(tvb, tr, p_t38_packet_conv);
+	}
+
+	col_append_str(pinfo->cinfo, COL_INFO, "TCP: IFPPacket");
+
+	while(tvb_reported_length_remaining(tvb,offset)>0)
+	{
+		next_tvb = tvb_new_subset_remaining(tvb, offset);
+		offset += dissect_IFPPacket_PDU(next_tvb, pinfo, tr, NULL);
+		ifp_packet_number++;
+
+		if(tvb_reported_length_remaining(tvb,offset)>0){
+			if(t38_tpkt_usage == T38_TPKT_ALWAYS){
+				proto_tree_add_expert_format(tr, pinfo, &ei_t38_malformed, tvb, offset, tvb_reported_length_remaining(tvb, offset),
+						"[MALFORMED PACKET or wrong preference settings]");
+				col_append_str(pinfo->cinfo, COL_INFO, " [Malformed?]");
+				break;
+			}else {
+				col_append_fstr(pinfo->cinfo, COL_INFO, " IFPPacket#%u",ifp_packet_number);
+			}
+		}
+	}
+
+	return tvb_captured_length(tvb);
+}
+
+static int
+dissect_t38_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+	primary_part = TRUE;
+
+	if(t38_tpkt_usage == T38_TPKT_ALWAYS){
+		dissect_tpkt_encap(tvb,pinfo,tree,t38_tpkt_reassembly,t38_tcp_pdu_handle);
+	}
+	else if((t38_tpkt_usage == T38_TPKT_NEVER) || (is_tpkt(tvb,1) == -1)){
+		dissect_t38_tcp_pdu(tvb, pinfo, tree, data);
+	}
+	else {
+		dissect_tpkt_encap(tvb,pinfo,tree,t38_tpkt_reassembly,t38_tcp_pdu_handle);
+	}
+	return tvb_captured_length(tvb);
+}
+
+/* Look for conversation info and display any setup info found */
+void
+show_setup_info(tvbuff_t *tvb, proto_tree *tree, t38_conv *p_t38_conversation)
+{
+	proto_tree *t38_setup_tree;
+	proto_item *ti;
+
+	if (!p_t38_conversation || p_t38_conversation->setup_frame_number == 0) {
+		/* there is no Setup info */
+		return;
+	}
+
+	ti =  proto_tree_add_string_format(tree, hf_t38_setup, tvb, 0, 0,
+                      "",
+                      "Stream setup by %s (frame %u)",
+                      p_t38_conversation->setup_method,
+                      p_t38_conversation->setup_frame_number);
+    proto_item_set_generated(ti);
+    t38_setup_tree = proto_item_add_subtree(ti, ett_t38_setup);
+    if (t38_setup_tree)
+    {
+		/* Add details into subtree */
+		proto_item* item = proto_tree_add_uint(t38_setup_tree, hf_t38_setup_frame,
+                                                               tvb, 0, 0, p_t38_conversation->setup_frame_number);
+		proto_item_set_generated(item);
+		item = proto_tree_add_string(t38_setup_tree, hf_t38_setup_method,
+                                                     tvb, 0, 0, p_t38_conversation->setup_method);
+		proto_item_set_generated(item);
+    }
+}
+
+/* This function tries to understand if the payload is sitting on top of AC DR */
+static gboolean
+dissect_t38_acdr_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
+{
+	guint acdr_prot = GPOINTER_TO_UINT(p_get_proto_data(pinfo->pool, pinfo, proto_acdr, 0));
+	if (acdr_prot == ACDR_T38)
+		return dissect_t38_udp(tvb, pinfo, tree, NULL);
+	return FALSE;
+}
+
+
+/* Wireshark Protocol Registration */
+void
+proto_register_t38(void)
+{
+	static hf_register_info hf[] =
+	{
+    { &hf_t38_IFPPacket_PDU,
+      { "IFPPacket", "t38.IFPPacket_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_UDPTLPacket_PDU,
+      { "UDPTLPacket", "t38.UDPTLPacket_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_type_of_msg,
+      { "type-of-msg", "t38.type_of_msg",
+        FT_UINT32, BASE_DEC, VALS(t38_Type_of_msg_vals), 0,
+        NULL, HFILL }},
+    { &hf_t38_data_field,
+      { "data-field", "t38.data_field",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_t30_indicator,
+      { "t30-indicator", "t38.t30_indicator",
+        FT_UINT32, BASE_DEC, VALS(t38_T30_indicator_vals), 0,
+        NULL, HFILL }},
+    { &hf_t38_t30_data,
+      { "t30-data", "t38.t30_data",
+        FT_UINT32, BASE_DEC, VALS(t38_T30_data_vals), 0,
+        NULL, HFILL }},
+    { &hf_t38_Data_Field_item,
+      { "Data-Field item", "t38.Data_Field_item_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_field_type,
+      { "field-type", "t38.field_type",
+        FT_UINT32, BASE_DEC, VALS(t38_T_field_type_vals), 0,
+        NULL, HFILL }},
+    { &hf_t38_field_data,
+      { "field-data", "t38.field_data",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_seq_number,
+      { "seq-number", "t38.seq_number",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_primary_ifp_packet,
+      { "primary-ifp-packet", "t38.primary_ifp_packet_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_error_recovery,
+      { "error-recovery", "t38.error_recovery",
+        FT_UINT32, BASE_DEC, VALS(t38_T_error_recovery_vals), 0,
+        NULL, HFILL }},
+    { &hf_t38_secondary_ifp_packets,
+      { "secondary-ifp-packets", "t38.secondary_ifp_packets",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_secondary_ifp_packets_item,
+      { "secondary-ifp-packets item", "t38.secondary_ifp_packets_item_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "OpenType_IFPPacket", HFILL }},
+    { &hf_t38_fec_info,
+      { "fec-info", "t38.fec_info_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_fec_npackets,
+      { "fec-npackets", "t38.fec_npackets",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "INTEGER", HFILL }},
+    { &hf_t38_fec_data,
+      { "fec-data", "t38.fec_data",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_t38_fec_data_item,
+      { "fec-data item", "t38.fec_data_item",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "OCTET_STRING", HFILL }},
+		{   &hf_t38_setup,
+		    { "Stream setup", "t38.setup", FT_STRING, BASE_NONE,
+		    NULL, 0x0, "Stream setup, method and frame number", HFILL }},
+		{   &hf_t38_setup_frame,
+            { "Stream frame", "t38.setup-frame", FT_FRAMENUM, BASE_NONE,
+            NULL, 0x0, "Frame that set up this stream", HFILL }},
+        {   &hf_t38_setup_method,
+            { "Stream Method", "t38.setup-method", FT_STRING, BASE_NONE,
+            NULL, 0x0, "Method used to set up this stream", HFILL }},
+		{&hf_t38_fragments,
+			{"Message fragments", "t38.fragments",
+			FT_NONE, BASE_NONE, NULL, 0x00,	NULL, HFILL } },
+		{&hf_t38_fragment,
+			{"Message fragment", "t38.fragment",
+			FT_FRAMENUM, BASE_NONE, NULL, 0x00, NULL, HFILL } },
+		{&hf_t38_fragment_overlap,
+			{"Message fragment overlap", "t38.fragment.overlap",
+			FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } },
+		{&hf_t38_fragment_overlap_conflicts,
+			{"Message fragment overlapping with conflicting data",
+			"t38.fragment.overlap.conflicts",
+			FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } },
+		{&hf_t38_fragment_multiple_tails,
+			{"Message has multiple tail fragments",
+			"t38.fragment.multiple_tails",
+			FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } },
+		{&hf_t38_fragment_too_long_fragment,
+			{"Message fragment too long", "t38.fragment.too_long_fragment",
+			FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } },
+		{&hf_t38_fragment_error,
+			{"Message defragmentation error", "t38.fragment.error",
+			FT_FRAMENUM, BASE_NONE, NULL, 0x00, NULL, HFILL } },
+		{&hf_t38_fragment_count,
+			{"Message fragment count", "t38.fragment.count",
+			FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } },
+		{&hf_t38_reassembled_in,
+			{"Reassembled in", "t38.reassembled.in",
+			FT_FRAMENUM, BASE_NONE, NULL, 0x00, NULL, HFILL } },
+		{&hf_t38_reassembled_length,
+			{"Reassembled T38 length", "t38.reassembled.length",
+			FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } },
+	};
+
+	static gint *ett[] =
+	{
+		&ett_t38,
+    &ett_t38_IFPPacket,
+    &ett_t38_Type_of_msg,
+    &ett_t38_Data_Field,
+    &ett_t38_Data_Field_item,
+    &ett_t38_UDPTLPacket,
+    &ett_t38_T_error_recovery,
+    &ett_t38_T_secondary_ifp_packets,
+    &ett_t38_T_fec_info,
+    &ett_t38_T_fec_data,
+		&ett_t38_setup,
+		&ett_data_fragment,
+		&ett_data_fragments
+	};
+
+	static ei_register_info ei[] = {
+		{ &ei_t38_malformed, { "t38.malformed", PI_MALFORMED, PI_ERROR, "Malformed packet", EXPFILL }},
+	};
+
+	module_t *t38_module;
+	expert_module_t* expert_t38;
+
+	proto_t38 = proto_register_protocol("T.38", "T.38", "t38");
+	proto_register_field_array(proto_t38, hf, array_length(hf));
+	proto_register_subtree_array(ett, array_length(ett));
+	expert_t38 = expert_register_protocol(proto_t38);
+	expert_register_field_array(expert_t38, ei, array_length(ei));
+	t38_udp_handle=register_dissector("t38_udp", dissect_t38_udp, proto_t38);
+	t38_tcp_handle=register_dissector("t38_tcp", dissect_t38_tcp, proto_t38);
+	t38_tcp_pdu_handle=register_dissector("t38_tcp_pdu", dissect_t38_tcp_pdu, proto_t38);
+
+	/* Register reassemble tables for HDLC */
+	reassembly_table_register(&data_reassembly_table,
+                              &addresses_reassembly_table_functions);
+
+	t38_tap = register_tap("t38");
+
+	t38_module = prefs_register_protocol(proto_t38, NULL);
+	prefs_register_bool_preference(t38_module, "use_pre_corrigendum_asn1_specification",
+	    "Use the Pre-Corrigendum ASN.1 specification",
+	    "Whether the T.38 dissector should decode using the Pre-Corrigendum T.38 "
+		"ASN.1 specification (1998).",
+	    &use_pre_corrigendum_asn1_specification);
+	prefs_register_bool_preference(t38_module, "dissect_possible_rtpv2_packets_as_rtp",
+	    "Dissect possible RTP version 2 packets with RTP dissector",
+	    "Whether a UDP packet that looks like RTP version 2 packet will "
+		"be dissected as RTP packet or T.38 packet. If enabled there is a risk that T.38 UDPTL "
+		"packets with sequence number higher than 32767 may be dissected as RTP.",
+	    &dissect_possible_rtpv2_packets_as_rtp);
+	prefs_register_bool_preference(t38_module, "reassembly",
+		"Reassemble T.38 PDUs over TPKT over TCP",
+		"Whether the dissector should reassemble T.38 PDUs spanning multiple TCP segments "
+		"when TPKT is used over TCP. "
+		"To use this option, you must also enable \"Allow subdissectors to reassemble "
+		"TCP streams\" in the TCP protocol settings.",
+		&t38_tpkt_reassembly);
+	prefs_register_enum_preference(t38_module, "tpkt_usage",
+		"TPKT used over TCP",
+		"Whether T.38 is used with TPKT for TCP",
+		(gint *)&t38_tpkt_usage,t38_tpkt_options,FALSE);
+
+	prefs_register_bool_preference(t38_module, "show_setup_info",
+                "Show stream setup information",
+                "Where available, show which protocol and frame caused "
+                "this T.38 stream to be created",
+                &global_t38_show_setup_info);
+
+}
+
+void
+proto_reg_handoff_t38(void)
+{
+	rtp_handle = find_dissector_add_dependency("rtp", proto_t38);
+	t30_hdlc_handle = find_dissector_add_dependency("t30.hdlc", proto_t38);
+	proto_acdr = proto_get_id_by_filter_name("acdr");
+	data_handle = find_dissector("data");
+	dissector_add_for_decode_as("tcp.port", t38_tcp_handle);
+	dissector_add_for_decode_as("udp.port", t38_udp_handle);
+	heur_dissector_add("udp", dissect_t38_acdr_heur, "T38 over AC DR", "t38_acdr", proto_t38, HEURISTIC_ENABLE);
+	dissector_add_uint("acdr.media_type", ACDR_T38, t38_udp_handle);
+}