From Mathias Guettler:

New dissector for Air/Ground Datalink ICAO doc 9705 Ed2: ULCS, CM, CPDLC.

https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=8903

svn path=/trunk/; revision=51766

1 files changed, 2640 insertions, 0 deletions

diff --git a/epan/dissectors/packet-atn-ulcs.c b/epan/dissectors/packet-atn-ulcs.c
new file mode 100644
index 0000000000..7aeccc95d4
--- /dev/null
+++ b/epan/dissectors/packet-atn-ulcs.c
@@ -0,0 +1,2640 @@
+/* Do not modify this file. Changes will be overwritten.                      */
+/* Generated automatically by the ASN.1 to Wireshark dissector compiler       */
+/* packet-atn-ulcs.c                                                          */
+/* ../../tools/asn2wrs.py -u -L -p atn-ulcs -c ./atn-ulcs.cnf -s ./packet-atn-ulcs-template -D . -O ../../epan/dissectors atn-ulcs.asn */
+
+/* Input file: packet-atn-ulcs-template.c */
+
+#line 1 "../../asn1/atn-ulcs/packet-atn-ulcs-template.c"
+/* c-basic-offset: 2; tab-width: 2; indent-tabs-mode: t
+ * vi: set shiftwidth=2 tabstop=2 noexpandtab:
+ * :indentSize=2:tabSize=2:noTabs=false:
+ */
+
+/* packet-atn-ulcs.c
+ * By Mathias Guettler <guettler@web.de>
+ * Copyright 2013
+ *
+ * Routines for ATN upper layer
+ * protocol packet disassembly
+
+ * ATN upper layers are embedded within OSI Layer 4 (COTP).
+ *
+ * ATN upper layers contain:
+ * Session Layer (NUL protocol option)
+ * Presentation Layer (NUL protocol option)
+ * ATN upper Layer/Application (ACSE PDU or PDV-list PDU)
+
+ * ATN applications protocols (i.e. CM or CPDLC) are contained within
+ * ACSE user-information or PDV presentation data.
+
+ * details see:
+ * http://en.wikipedia.org/wiki/CPDLC
+ * http://members.optusnet.com.au/~cjr/introduction.htm
+ 
+ * standards:
+ * http://legacy.icao.int/anb/panels/acp/repository.cfm
+
+ * note:
+ * We are dealing with ATN/ULCS aka ICAO Doc 9705 Ed2 here
+ * (don't think there is an ULCS equivalent for "FANS-1/A ").
+
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/*
+ developper comments:
+why not using existing ses, pres and acse dissectors ?
+		ATN upper layers are derived from OSI standards for session,
+		presentation and application but the encoding differs
+		(it's PER instead of BER encoding to save bandwith).
+		Session and presentation use the "null" encoding option,
+		meaning that they are only present at connection establishment
+		and ommitted otherwise.
+		Instead of adapting existing dissectors it seemed simpler and cleaner
+		to implement everything the new atn-ulcs dissector.
+		
+why using conversations ?
+		PER encoded user data is ambigous; the same encoding may apply to a CM or
+		CPDLC PDU. The workaround is to decode on a transport connection basis.
+		I use my own version of conversations to identify
+		the transport connection the PDU belongs to for the standard functions
+		from "conversation.h" didn't work out.
+
+what is the use of AARQ/AARE data ?
+		Converstions should be maintained on the COTP layer in a standard way
+		for there are usually more packets available than in the layers above.
+		In the worst case my dissector is called from a DT packet which
+		has destination references but no source reference.
+		I have to guess the reference used the other way round
+		(curently I am using ACSE PDU'S used during OSI connection establishment for that).
+		The idea is that each ACSE AARQ is answered by ACSE AARE and having this sequence
+		I have all the source/destination references for this transport connection.
+		I use AARQ/AARE data to store the source/destination reference of AARQ as well
+		as the optional ae-qualifier which tells me the application and
+		the dissector I have to use.
+		This approach donesn't work well when there are interleaving AARQ/AARE sequences for
+		the same aircraft.
+
+which ATN standard is supported ?
+		The dissector has been tested with ICAO doc9705 Edition2 compliant traffic.
+		No ATN Secutity is supported.
+		note:
+		The ATN upper layers are derived from OSI standards (ICAO DOC 9705)
+		while ATN/IPS (ICAO DOC 9896) which is entirely based on IPV6.
+		
+*/
+
+/*
+ known defects/deficiencies:
+
+-	user-information within AARE is sometines not decoded due to an unset flag
+		(the field is optional). As far as I can tell asn2wrs is right here,
+		but on the other hand I know that in all of this cases user-information
+		is present and is processed by the ATN end system.
+		Maybe a true ATN expert may help me out here.
+
+	- The conversation handling is based on src/dst addresses as well as
+		source or destination references depending on the TP4 packet type.
+		This means that after some time these references get reused for
+		new conversations. This almost certain happens for traces longer
+		than one day rendering this dissector unsuitable for captures exceeding
+		this one day. 
+		
+*/
+
+#include "config.h"
+
+#include <glib.h>
+#include <epan/packet.h>
+#include <epan/dissectors/packet-ber.h>
+#include <epan/dissectors/packet-per.h>
+#include <epan/emem.h>
+#include <epan/address.h>
+#include <epan/conversation.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "packet-atn-ulcs.h"
+
+#define ATN_ACSE_PROTO "ICAO Doc9705 ULCS ACSE (ISO 8649/8650-1:1996)"
+#define ATN_ULCS_PROTO "ICAO Doc9705 ULCS"
+
+static heur_dissector_list_t atn_ulcs_heur_subdissector_list;
+
+/* presentation subdissectors i.e. CM, CPDLC */
+static dissector_handle_t atn_cm_handle = NULL;
+static dissector_handle_t atn_cpdlc_handle = NULL;
+
+static int proto_atn_ulcs          = -1;
+static guint32 ulcs_context_value = 0;
+static const char *object_identifier_id;
+
+static emem_tree_t *aarq_data_tree = NULL;
+static emem_tree_t *atn_conversation_tree = NULL;
+
+
+static proto_tree *root_tree = NULL;
+
+/* forward declarations for functions generated from asn1 */
+static int dissect_atn_ulcs_T_externalt_encoding_single_asn1_type(
+		tvbuff_t *tvb _U_,
+		int offset _U_,
+		asn1_ctx_t *actx _U_,
+		proto_tree *tree _U_,
+		int hf_index
+		_U_);
+
+static int dissect_atn_ulcs_T_externalt_encoding_octet_aligned(
+		tvbuff_t *tvb _U_,
+		int offset _U_,
+		asn1_ctx_t *actx _U_,
+		proto_tree *tree _U_,
+		int hf_index _U_);
+
+static int dissect_atn_ulcs_T_externalt_encoding_arbitrary(
+		tvbuff_t *tvb _U_,
+		int offset _U_,
+		asn1_ctx_t *actx _U_,
+		proto_tree *tree _U_,
+		int hf_index _U_);
+		
+static void dissect_ACSE_apdu_PDU(
+		tvbuff_t *tvb _U_,
+		packet_info *pinfo _U_,
+		proto_tree *tree _U_);
+		
+guint32 dissect_per_object_descriptor_t(
+		tvbuff_t *tvb,
+		guint32 offset,
+		asn1_ctx_t *actx,
+		proto_tree *tree,
+		int hf_index,
+		tvbuff_t **value_tvb);
+
+static gint	dissect_atn_ulcs(
+		tvbuff_t *tvb,
+		packet_info *pinfo,
+		proto_tree	*tree,
+		void *data _U_);
+
+
+/*--- Included file: packet-atn-ulcs-hf.c ---*/
+#line 1 "../../asn1/atn-ulcs/packet-atn-ulcs-hf.c"
+static int hf_atn_ulcs_Fully_encoded_data_PDU = -1;  /* Fully_encoded_data */
+static int hf_atn_ulcs_ACSE_apdu_PDU = -1;        /* ACSE_apdu */
+static int hf_atn_ulcs_Fully_encoded_data_item = -1;  /* PDV_list */
+static int hf_atn_ulcs_transfer_syntax_name = -1;  /* Transfer_syntax_name */
+static int hf_atn_ulcs_presentation_context_identifier = -1;  /* Presentation_context_identifier */
+static int hf_atn_ulcs_presentation_data_values = -1;  /* T_presentation_data_values */
+static int hf_atn_ulcs_pdv_list_presentation_data_values_single_asn1_type = -1;  /* T_pdv_list_presentation_data_values_single_asn1_type */
+static int hf_atn_ulcs_octet_aligned = -1;        /* OCTET_STRING */
+static int hf_atn_ulcs_pdv_list_presentation_data_values_arbitrary = -1;  /* T_pdv_list_presentation_data_values_arbitrary */
+static int hf_atn_ulcs_direct_reference = -1;     /* OBJECT_IDENTIFIER */
+static int hf_atn_ulcs_indirect_reference = -1;   /* INTEGER */
+static int hf_atn_ulcs_data_value_descriptor = -1;  /* T_data_value_descriptor */
+static int hf_atn_ulcs_encoding = -1;             /* T_encoding */
+static int hf_atn_ulcs_externalt_encoding_single_asn1_type = -1;  /* T_externalt_encoding_single_asn1_type */
+static int hf_atn_ulcs_externalt_encoding_octet_aligned = -1;  /* T_externalt_encoding_octet_aligned */
+static int hf_atn_ulcs_externalt_encoding_arbitrary = -1;  /* T_externalt_encoding_arbitrary */
+static int hf_atn_ulcs_aarq = -1;                 /* AARQ_apdu */
+static int hf_atn_ulcs_aare = -1;                 /* AARE_apdu */
+static int hf_atn_ulcs_rlrq = -1;                 /* RLRQ_apdu */
+static int hf_atn_ulcs_rlre = -1;                 /* RLRE_apdu */
+static int hf_atn_ulcs_abrt = -1;                 /* ABRT_apdu */
+static int hf_atn_ulcs_aarq_apdu_protocol_version = -1;  /* T_aarq_apdu_protocol_version */
+static int hf_atn_ulcs_application_context_name = -1;  /* Application_context_name */
+static int hf_atn_ulcs_called_AP_title = -1;      /* AP_title */
+static int hf_atn_ulcs_called_AE_qualifier = -1;  /* AE_qualifier */
+static int hf_atn_ulcs_called_AP_invocation_identifier = -1;  /* AP_invocation_identifier */
+static int hf_atn_ulcs_called_AE_invocation_identifier = -1;  /* AE_invocation_identifier */
+static int hf_atn_ulcs_calling_AP_title = -1;     /* AP_title */
+static int hf_atn_ulcs_calling_AE_qualifier = -1;  /* AE_qualifier */
+static int hf_atn_ulcs_calling_AP_invocation_identifier = -1;  /* AP_invocation_identifier */
+static int hf_atn_ulcs_calling_AE_invocation_identifier = -1;  /* AE_invocation_identifier */
+static int hf_atn_ulcs_sender_acse_requirements = -1;  /* ACSE_requirements */
+static int hf_atn_ulcs_mechanism_name = -1;       /* Mechanism_name */
+static int hf_atn_ulcs_calling_authentication_value = -1;  /* Authentication_value */
+static int hf_atn_ulcs_application_context_name_list = -1;  /* Application_context_name_list */
+static int hf_atn_ulcs_implementation_information = -1;  /* Implementation_data */
+static int hf_atn_ulcs_user_information = -1;     /* Association_information */
+static int hf_atn_ulcs_aare_apdu_protocol_version = -1;  /* T_aare_apdu_protocol_version */
+static int hf_atn_ulcs_result = -1;               /* Associate_result */
+static int hf_atn_ulcs_result_source_diagnostic = -1;  /* Associate_source_diagnostic */
+static int hf_atn_ulcs_responding_AP_title = -1;  /* AP_title */
+static int hf_atn_ulcs_responding_AE_qualifier = -1;  /* AE_qualifier */
+static int hf_atn_ulcs_responding_AP_invocation_identifier = -1;  /* AP_invocation_identifier */
+static int hf_atn_ulcs_responding_AE_invocation_identifier = -1;  /* AE_invocation_identifier */
+static int hf_atn_ulcs_responder_acse_requirements = -1;  /* ACSE_requirements */
+static int hf_atn_ulcs_responding_authentication_value = -1;  /* Authentication_value */
+static int hf_atn_ulcs_rlrq_apdu_request_reason = -1;  /* Release_request_reason */
+static int hf_atn_ulcs_rlre_apdu_response_reason = -1;  /* Release_response_reason */
+static int hf_atn_ulcs_abort_source = -1;         /* ABRT_source */
+static int hf_atn_ulcs_abort_diagnostic = -1;     /* ABRT_diagnostic */
+static int hf_atn_ulcs_Application_context_name_list_item = -1;  /* Application_context_name */
+static int hf_atn_ulcs_ap_title_form2 = -1;       /* AP_title_form2 */
+static int hf_atn_ulcs_ap_title_form1 = -1;       /* AP_title_form1 */
+static int hf_atn_ulcs_ae_qualifier_form2 = -1;   /* AE_qualifier_form2 */
+static int hf_atn_ulcs_ae_qualifier_form1 = -1;   /* AE_qualifier_form1 */
+static int hf_atn_ulcs_acse_service_user = -1;    /* T_acse_service_user */
+static int hf_atn_ulcs_acse_service_provider = -1;  /* T_acse_service_provider */
+static int hf_atn_ulcs_Association_information_item = -1;  /* EXTERNALt */
+static int hf_atn_ulcs_charstring = -1;           /* OCTET_STRING */
+static int hf_atn_ulcs_bitstring = -1;            /* BIT_STRING */
+static int hf_atn_ulcs_external = -1;             /* EXTERNAL */
+static int hf_atn_ulcs_other = -1;                /* T_other */
+static int hf_atn_ulcs_other_mechanism_name = -1;  /* OBJECT_IDENTIFIER */
+static int hf_atn_ulcs_other_mechanism_value = -1;  /* T_other_mechanism_value */
+static int hf_atn_ulcs_rdnSequence = -1;          /* RDNSequence */
+static int hf_atn_ulcs_RDNSequence_item = -1;     /* RelativeDistinguishedName */
+static int hf_atn_ulcs_RelativeDistinguishedName_item = -1;  /* AttributeTypeAndValue */
+static int hf_atn_ulcs_null = -1;                 /* NULL */
+/* named bits */
+static int hf_atn_ulcs_T_aarq_apdu_protocol_version_version1 = -1;
+static int hf_atn_ulcs_T_aare_apdu_protocol_version_version1 = -1;
+static int hf_atn_ulcs_ACSE_requirements_authentication = -1;
+static int hf_atn_ulcs_ACSE_requirements_application_context_negotiation = -1;
+
+/*--- End of included file: packet-atn-ulcs-hf.c ---*/
+#line 196 "../../asn1/atn-ulcs/packet-atn-ulcs-template.c"
+
+
+/*--- Included file: packet-atn-ulcs-ett.c ---*/
+#line 1 "../../asn1/atn-ulcs/packet-atn-ulcs-ett.c"
+static gint ett_atn_ulcs_Fully_encoded_data = -1;
+static gint ett_atn_ulcs_PDV_list = -1;
+static gint ett_atn_ulcs_T_presentation_data_values = -1;
+static gint ett_atn_ulcs_EXTERNALt = -1;
+static gint ett_atn_ulcs_T_encoding = -1;
+static gint ett_atn_ulcs_ACSE_apdu = -1;
+static gint ett_atn_ulcs_AARQ_apdu = -1;
+static gint ett_atn_ulcs_T_aarq_apdu_protocol_version = -1;
+static gint ett_atn_ulcs_AARE_apdu = -1;
+static gint ett_atn_ulcs_T_aare_apdu_protocol_version = -1;
+static gint ett_atn_ulcs_RLRQ_apdu = -1;
+static gint ett_atn_ulcs_RLRE_apdu = -1;
+static gint ett_atn_ulcs_ABRT_apdu = -1;
+static gint ett_atn_ulcs_ACSE_requirements = -1;
+static gint ett_atn_ulcs_Application_context_name_list = -1;
+static gint ett_atn_ulcs_AP_title = -1;
+static gint ett_atn_ulcs_AE_qualifier = -1;
+static gint ett_atn_ulcs_Associate_source_diagnostic = -1;
+static gint ett_atn_ulcs_Association_information = -1;
+static gint ett_atn_ulcs_Authentication_value = -1;
+static gint ett_atn_ulcs_T_other = -1;
+static gint ett_atn_ulcs_Name = -1;
+static gint ett_atn_ulcs_RDNSequence = -1;
+static gint ett_atn_ulcs_RelativeDistinguishedName = -1;
+static gint ett_atn_ulcs_AttributeTypeAndValue = -1;
+
+/*--- End of included file: packet-atn-ulcs-ett.c ---*/
+#line 198 "../../asn1/atn-ulcs/packet-atn-ulcs-template.c"
+static gint ett_atn_ulcs = -1;
+static gint ett_atn_acse = -1;
+
+
+/*--- Included file: packet-atn-ulcs-fn.c ---*/
+#line 1 "../../asn1/atn-ulcs/packet-atn-ulcs-fn.c"
+
+
+static int
+dissect_atn_ulcs_Transfer_syntax_name(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_object_identifier(tvb, offset, actx, tree, hf_index, NULL);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Presentation_context_identifier_vals[] = {
+  {   1, "acse-apdu" },
+  {   2, "reserved" },
+  {   3, "user-ase-apdu" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_Presentation_context_identifier(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,
+				1U,
+				127U,
+				&ulcs_context_value,
+				TRUE);
+
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_T_pdv_list_presentation_data_values_single_asn1_type(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, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_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 int
+dissect_atn_ulcs_T_pdv_list_presentation_data_values_arbitrary(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+
+		packet_info * pinfo = actx->pinfo;
+		tvbuff_t *tvb_usr = NULL; 
+		proto_item *ti = NULL; 
+		proto_tree *atn_ulcs_tree = NULL;
+		atn_conversation_t *atn_cv = NULL;
+
+		/* extract bitstring into new tvb buffer */
+		offset = dissect_per_bit_string(
+				tvb,
+				offset,
+				actx,
+				tree,
+				hf_index,
+				NO_BOUND,
+				NO_BOUND,
+				FALSE,
+				&tvb_usr);
+
+		/* call appropiate dissector for bitstring data */
+		switch(ulcs_context_value){
+				case  1: /* ACSE PDU*/
+						ti = proto_tree_add_text(
+								root_tree,
+								tvb,
+								offset,
+								0,
+								ATN_ACSE_PROTO );
+						atn_ulcs_tree = proto_item_add_subtree(ti, ett_atn_acse);
+
+						dissect_ACSE_apdu_PDU(
+								tvb_new_subset_remaining(tvb_usr, 0),
+								pinfo,
+								atn_ulcs_tree);
+						break;
+					case  3: /* USER data; call subdissector for CM, CPDLC ...  */
+
+							/* using dstref for PDV-list only occurrs in DT */
+							atn_cv = find_atn_conversation(
+									&pinfo->dst,
+									pinfo->clnp_dstref,
+									&pinfo->src);
+
+							if(atn_cv) {
+									switch(atn_cv->ae_qualifier){
+											case cma: /* contact management */
+													call_dissector_with_data(
+															atn_cm_handle,
+															tvb_new_subset_remaining(tvb_usr, 0),
+															pinfo,
+															root_tree,
+															NULL);
+													break;
+											case cpdlc: /* plain old cpdlc */
+											case pmcpdlc: /* protected mode cpdlc */
+													call_dissector_with_data(
+															atn_cpdlc_handle,
+															tvb_new_subset_remaining(tvb_usr, 0),
+															pinfo,
+															root_tree,
+															NULL);
+													break;
+											default: /* unknown or unhandled datalink application */
+													dissector_try_heuristic(
+															atn_ulcs_heur_subdissector_list,
+															tvb_new_subset_remaining(tvb_usr,0),
+															actx->pinfo,
+															root_tree,
+															NULL);
+													break;
+									}
+							}
+							else{
+									dissector_try_heuristic(
+											atn_ulcs_heur_subdissector_list,
+											tvb_new_subset_remaining(tvb_usr,0),
+											actx->pinfo,
+											root_tree,
+											NULL);
+							}
+							break;
+					default:
+							break;
+		} /* switch(ulcs_context_value) */
+
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_T_presentation_data_values_vals[] = {
+  {   0, "single-ASN1-type" },
+  {   1, "octet-aligned" },
+  {   2, "arbitrary" },
+  { 0, NULL }
+};
+
+static const per_choice_t T_presentation_data_values_choice[] = {
+  {   0, &hf_atn_ulcs_pdv_list_presentation_data_values_single_asn1_type, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_pdv_list_presentation_data_values_single_asn1_type },
+  {   1, &hf_atn_ulcs_octet_aligned, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_OCTET_STRING },
+  {   2, &hf_atn_ulcs_pdv_list_presentation_data_values_arbitrary, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_pdv_list_presentation_data_values_arbitrary },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_T_presentation_data_values(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_atn_ulcs_T_presentation_data_values, T_presentation_data_values_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+static const per_sequence_t PDV_list_sequence[] = {
+  { &hf_atn_ulcs_transfer_syntax_name, ASN1_NO_EXTENSIONS     , ASN1_OPTIONAL    , dissect_atn_ulcs_Transfer_syntax_name },
+  { &hf_atn_ulcs_presentation_context_identifier, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_Presentation_context_identifier },
+  { &hf_atn_ulcs_presentation_data_values, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_T_presentation_data_values },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_PDV_list(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_atn_ulcs_PDV_list, PDV_list_sequence);
+
+  return offset;
+}
+
+
+static const per_sequence_t Fully_encoded_data_sequence_of[1] = {
+  { &hf_atn_ulcs_Fully_encoded_data_item, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_PDV_list },
+};
+
+static int
+dissect_atn_ulcs_Fully_encoded_data(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_constrained_sequence_of(tvb, offset, actx, tree, hf_index,
+                                                  ett_atn_ulcs_Fully_encoded_data, Fully_encoded_data_sequence_of,
+                                                  1, 1, TRUE);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_OBJECT_IDENTIFIER(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_object_identifier(tvb, offset, actx, tree, hf_index, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_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_atn_ulcs_T_data_value_descriptor(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,
+			-1,
+			-1,
+			FALSE,
+			&actx->external.data_value_descriptor);
+  actx->external.data_value_descr_present = TRUE;
+
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_T_externalt_encoding_single_asn1_type(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, NULL);
+
+
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_T_externalt_encoding_octet_aligned(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 int
+dissect_atn_ulcs_T_externalt_encoding_arbitrary(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+	tvbuff_t *tvb_usr = NULL;
+	packet_info * pinfo = actx->pinfo;
+	atn_conversation_t *atn_cv = NULL;
+
+	/* decode bit-string user data within ACSE  */
+	offset = dissect_per_bit_string(
+		tvb,
+		offset,
+		actx,
+		tree, hf_index,
+		NO_BOUND,
+		NO_BOUND,
+		FALSE,
+		&tvb_usr);
+
+	/* DT: dstref present, srcref is always zero */
+	if((pinfo->clnp_dstref) && (!pinfo->clnp_srcref)){
+
+		atn_cv = find_atn_conversation(
+				&pinfo->dst,
+				pinfo->clnp_dstref, 
+        &pinfo->src);
+	}
+	/* CR: srcref present, dstref always zero */
+	if((pinfo->clnp_srcref) && (!pinfo->clnp_dstref)){
+
+		atn_cv = find_atn_conversation(
+				&pinfo->src,
+				pinfo->clnp_srcref,
+        &pinfo->dst);
+	}
+	/* CC: srcref and dstref present */
+	if((pinfo->clnp_srcref) && (pinfo->clnp_dstref)){
+
+		atn_cv = find_atn_conversation(
+				&pinfo->src,
+				pinfo->clnp_srcref,
+        &pinfo->dst);
+	}
+
+	if(atn_cv) {
+			switch(atn_cv->ae_qualifier){
+				case cma: /* contact management */
+
+						call_dissector_with_data(
+									atn_cm_handle,
+									tvb_new_subset_remaining(tvb_usr, 0),
+									pinfo,
+									root_tree,
+									NULL);
+						break;
+				case cpdlc: /* plain old cpdlc */
+				case pmcpdlc: /* protected mode cpdlc */
+
+						call_dissector_with_data(
+									atn_cpdlc_handle,
+									tvb_new_subset_remaining(tvb_usr, 0),
+									pinfo,
+									root_tree,
+									NULL);
+						break;
+				default: /* unknown or unhandled datalink application */
+
+						dissector_try_heuristic(
+								atn_ulcs_heur_subdissector_list,
+								tvb_new_subset_remaining(tvb_usr,0),
+								actx->pinfo,
+								root_tree,
+								NULL);
+							break;
+				}
+	}else {
+
+		dissector_try_heuristic(
+						atn_ulcs_heur_subdissector_list,
+						tvb_new_subset_remaining(tvb_usr,0),
+						actx->pinfo,
+						root_tree,
+						NULL);
+	}
+
+	offset += tvb_length_remaining(tvb, offset);
+
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_T_encoding_vals[] = {
+  {   0, "single-ASN1-type" },
+  {   1, "octet-aligned" },
+  {   2, "arbitrary" },
+  { 0, NULL }
+};
+
+static const per_choice_t T_encoding_choice[] = {
+  {   0, &hf_atn_ulcs_externalt_encoding_single_asn1_type, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_externalt_encoding_single_asn1_type },
+  {   1, &hf_atn_ulcs_externalt_encoding_octet_aligned, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_externalt_encoding_octet_aligned },
+  {   2, &hf_atn_ulcs_externalt_encoding_arbitrary, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_externalt_encoding_arbitrary },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_T_encoding(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_atn_ulcs_T_encoding, T_encoding_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+static const per_sequence_t EXTERNALt_sequence[] = {
+  { &hf_atn_ulcs_direct_reference, ASN1_NO_EXTENSIONS     , ASN1_OPTIONAL    , dissect_atn_ulcs_OBJECT_IDENTIFIER },
+  { &hf_atn_ulcs_indirect_reference, ASN1_NO_EXTENSIONS     , ASN1_OPTIONAL    , dissect_atn_ulcs_INTEGER },
+  { &hf_atn_ulcs_data_value_descriptor, ASN1_NO_EXTENSIONS     , ASN1_OPTIONAL    , dissect_atn_ulcs_T_data_value_descriptor },
+  { &hf_atn_ulcs_encoding   , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_T_encoding },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_EXTERNALt(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_atn_ulcs_EXTERNALt, EXTERNALt_sequence);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_T_aarq_apdu_protocol_version(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_bit_string(tvb, offset, actx, tree, hf_index,
+                                     NO_BOUND, NO_BOUND, FALSE, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_Application_context_name(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_object_identifier(tvb, offset, actx, tree, hf_index, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_AP_title_form2(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_object_identifier(tvb, offset, actx, tree, hf_index, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_NULL(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_null(tvb, offset, actx, tree, hf_index);
+
+  return offset;
+}
+
+
+static const per_sequence_t AttributeTypeAndValue_sequence[] = {
+  { &hf_atn_ulcs_null       , ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_NULL },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_AttributeTypeAndValue(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_atn_ulcs_AttributeTypeAndValue, AttributeTypeAndValue_sequence);
+
+  return offset;
+}
+
+
+static const per_sequence_t RelativeDistinguishedName_set_of[1] = {
+  { &hf_atn_ulcs_RelativeDistinguishedName_item, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_AttributeTypeAndValue },
+};
+
+static int
+dissect_atn_ulcs_RelativeDistinguishedName(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_constrained_set_of(tvb, offset, actx, tree, hf_index,
+                                             ett_atn_ulcs_RelativeDistinguishedName, RelativeDistinguishedName_set_of,
+                                             1, NO_BOUND, FALSE);
+
+  return offset;
+}
+
+
+static const per_sequence_t RDNSequence_sequence_of[1] = {
+  { &hf_atn_ulcs_RDNSequence_item, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_RelativeDistinguishedName },
+};
+
+static int
+dissect_atn_ulcs_RDNSequence(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_atn_ulcs_RDNSequence, RDNSequence_sequence_of);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Name_vals[] = {
+  {   0, "rdnSequence" },
+  { 0, NULL }
+};
+
+static const per_choice_t Name_choice[] = {
+  {   0, &hf_atn_ulcs_rdnSequence, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_RDNSequence },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_Name(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_atn_ulcs_Name, Name_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_AP_title_form1(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_atn_ulcs_Name(tvb, offset, actx, tree, hf_index);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_AP_title_vals[] = {
+  {   0, "ap-title-form2" },
+  {   1, "ap-title-form1" },
+  { 0, NULL }
+};
+
+static const per_choice_t AP_title_choice[] = {
+  {   0, &hf_atn_ulcs_ap_title_form2, ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_AP_title_form2 },
+  {   1, &hf_atn_ulcs_ap_title_form1, ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_AP_title_form1 },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_AP_title(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_atn_ulcs_AP_title, AP_title_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_AE_qualifier_form2(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+		packet_info * pinfo = actx->pinfo;
+		atn_conversation_t *atn_cv = NULL;
+		guint32 ae_qualifier = 0;
+
+		/* dissect  ae-qualifier */
+		offset = dissect_per_integer(
+				tvb,
+				offset,
+				actx,
+				tree,
+				hf_index,
+				&ae_qualifier);
+
+
+		/*note: */
+		/* the field "calling-AE-qualifier" is optional, */
+		/* which means that we can exploit it only if it is present. */
+		/* We still depend on heuristical decoding of CM, CPDLC PDU's otherwise. */
+
+		/* AARQ/DT: dstref present, srcref is always zero */
+		if((pinfo->clnp_dstref) && (!pinfo->clnp_srcref)){
+				atn_cv = find_atn_conversation(&pinfo->dst,
+						pinfo->clnp_dstref,
+						&pinfo->src );
+		}
+
+		/* AARQ/CR: srcref present, dstref is always zero */
+		if((!pinfo->clnp_dstref) && (pinfo->clnp_srcref)){
+				atn_cv = find_atn_conversation(&pinfo->src,
+						pinfo->clnp_srcref,
+						&pinfo->dst );
+	}
+
+	if(atn_cv){
+			atn_cv->ae_qualifier = ae_qualifier;
+	}
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_AE_qualifier_form1(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_atn_ulcs_RelativeDistinguishedName(tvb, offset, actx, tree, hf_index);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_AE_qualifier_vals[] = {
+  {   0, "ae-qualifier-form2" },
+  {   1, "ae-qualifier-form1" },
+  { 0, NULL }
+};
+
+static const per_choice_t AE_qualifier_choice[] = {
+  {   0, &hf_atn_ulcs_ae_qualifier_form2, ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_AE_qualifier_form2 },
+  {   1, &hf_atn_ulcs_ae_qualifier_form1, ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_AE_qualifier_form1 },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_AE_qualifier(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_atn_ulcs_AE_qualifier, AE_qualifier_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_AP_invocation_identifier(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_atn_ulcs_AE_invocation_identifier(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_atn_ulcs_ACSE_requirements(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_bit_string(tvb, offset, actx, tree, hf_index,
+                                     NO_BOUND, NO_BOUND, FALSE, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_Mechanism_name(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+
+		offset = dissect_per_object_identifier(
+				tvb,
+				offset,
+				actx,
+				tree,
+				hf_index,
+				NULL);
+
+
+  offset = dissect_per_object_identifier(
+			tvb,
+			offset,
+			actx,
+			tree,
+			hf_index,
+			NULL);
+
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_BIT_STRING(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_bit_string(tvb, offset, actx, tree, hf_index,
+                                     NO_BOUND, NO_BOUND, FALSE, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_EXTERNAL(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_external_type(tvb, offset, actx, tree, hf_index, NULL);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_T_other_mechanism_value(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+
+		offset=call_ber_oid_callback(
+				object_identifier_id,
+				tvb,
+				offset,
+				actx->pinfo,
+				tree);
+
+
+		offset=call_ber_oid_callback(
+				object_identifier_id,
+				tvb,
+				offset,
+				actx->pinfo,
+				tree);
+
+
+  return offset;
+}
+
+
+static const per_sequence_t T_other_sequence[] = {
+  { &hf_atn_ulcs_other_mechanism_name, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_OBJECT_IDENTIFIER },
+  { &hf_atn_ulcs_other_mechanism_value, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_T_other_mechanism_value },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_T_other(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_atn_ulcs_T_other, T_other_sequence);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Authentication_value_vals[] = {
+  {   0, "charstring" },
+  {   1, "bitstring" },
+  {   2, "external" },
+  {   3, "other" },
+  { 0, NULL }
+};
+
+static const per_choice_t Authentication_value_choice[] = {
+  {   0, &hf_atn_ulcs_charstring , ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_OCTET_STRING },
+  {   1, &hf_atn_ulcs_bitstring  , ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_BIT_STRING },
+  {   2, &hf_atn_ulcs_external   , ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_EXTERNAL },
+  {   3, &hf_atn_ulcs_other      , ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_other },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_Authentication_value(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_atn_ulcs_Authentication_value, Authentication_value_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+static const per_sequence_t Application_context_name_list_sequence_of[1] = {
+  { &hf_atn_ulcs_Application_context_name_list_item, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_Application_context_name },
+};
+
+static int
+dissect_atn_ulcs_Application_context_name_list(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_atn_ulcs_Application_context_name_list, Application_context_name_list_sequence_of);
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_Implementation_data(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 Association_information_sequence_of[1] = {
+  { &hf_atn_ulcs_Association_information_item, ASN1_NO_EXTENSIONS     , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_EXTERNALt },
+};
+
+static int
+dissect_atn_ulcs_Association_information(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_constrained_sequence_of(tvb, offset, actx, tree, hf_index,
+                                                  ett_atn_ulcs_Association_information, Association_information_sequence_of,
+                                                  1, 1, TRUE);
+
+  return offset;
+}
+
+
+static const per_sequence_t AARQ_apdu_sequence[] = {
+  { &hf_atn_ulcs_aarq_apdu_protocol_version, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_T_aarq_apdu_protocol_version },
+  { &hf_atn_ulcs_application_context_name, ASN1_EXTENSION_ROOT    , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_Application_context_name },
+  { &hf_atn_ulcs_called_AP_title, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AP_title },
+  { &hf_atn_ulcs_called_AE_qualifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AE_qualifier },
+  { &hf_atn_ulcs_called_AP_invocation_identifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AP_invocation_identifier },
+  { &hf_atn_ulcs_called_AE_invocation_identifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AE_invocation_identifier },
+  { &hf_atn_ulcs_calling_AP_title, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AP_title },
+  { &hf_atn_ulcs_calling_AE_qualifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AE_qualifier },
+  { &hf_atn_ulcs_calling_AP_invocation_identifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AP_invocation_identifier },
+  { &hf_atn_ulcs_calling_AE_invocation_identifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AE_invocation_identifier },
+  { &hf_atn_ulcs_sender_acse_requirements, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_ACSE_requirements },
+  { &hf_atn_ulcs_mechanism_name, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Mechanism_name },
+  { &hf_atn_ulcs_calling_authentication_value, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Authentication_value },
+  { &hf_atn_ulcs_application_context_name_list, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Application_context_name_list },
+  { &hf_atn_ulcs_implementation_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Implementation_data },
+  { &hf_atn_ulcs_user_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Association_information },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_AARQ_apdu(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+		packet_info * pinfo = actx->pinfo;
+		aarq_data_t *aarq_data = NULL;
+		atn_conversation_t *atn_cv = NULL;
+		guint32 aircraft_24_bit_address = 0;
+
+		/* AARQ/DT: dstref present, srcref is always zero */
+		if((pinfo->clnp_dstref) && (!pinfo->clnp_srcref)){
+
+				atn_cv = find_atn_conversation(
+						&pinfo->dst,
+						pinfo->clnp_dstref,
+						&pinfo->src );
+				if(!atn_cv){
+						atn_cv = (atn_conversation_t*)
+								se_alloc(sizeof(atn_conversation_t));
+						atn_cv->ae_qualifier = unknown;
+						create_atn_conversation(&pinfo->dst,
+								pinfo->clnp_dstref,
+								&pinfo->src ,
+								atn_cv);
+				}
+		}
+
+	/* AARQ/CR: srcref present, dstref is always zero */
+		if((!pinfo->clnp_dstref) && (pinfo->clnp_srcref)){
+				atn_cv = find_atn_conversation(&pinfo->src,
+						pinfo->clnp_srcref,
+						&pinfo->dst );
+				if(!atn_cv){
+						atn_cv = (atn_conversation_t*)
+								se_alloc(sizeof(atn_conversation_t));
+						atn_cv->ae_qualifier = unknown;
+						create_atn_conversation(&pinfo->src,
+								pinfo->clnp_srcref,
+								&pinfo->dst ,
+								atn_cv);
+				}
+		}
+
+		/* conversation is to be created prior to decoding */
+		/* of "AE-qualifier-form2" which takes place here: */
+		  offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
+                                   ett_atn_ulcs_AARQ_apdu, AARQ_apdu_sequence);
+
+
+
+		/* save AARQ packet data to create a conversation  */
+		/* when decoding the following AARE PDU */
+		/* ATN applications CM and CPDLC are air/ground applications */
+		/* so there is always an aircraft (with its 24-bit address) */
+		/* and a ground facility. */
+		/* the assumption is that there is only one open AARQ/AARE */
+		/* dialog per aircraft at a time. */
+		/* the aircraft's 24-bit address is used as a key to each AARQ */
+		/* data. AARQ data is used to create a conversation with */
+		/* air and ground endpoints (based on NSAP's and transport references) */
+		/* when decoding AARE.*/
+		/* note: */
+		/* it may be more robust to create the conversation */
+		/* in the "ositp" dissector an to merely use the conversation here */
+		aircraft_24_bit_address =
+				get_aircraft_24_bit_address_from_nsap(pinfo);
+
+		/* search for aarq entry */
+		aarq_data = (aarq_data_t *) se_tree_lookup32(
+				aarq_data_tree,
+				aircraft_24_bit_address);
+
+		if(!aarq_data){  /* aarq data not found, create new record */
+
+				/* alloc aarq data */
+				aarq_data = (aarq_data_t*) se_alloc(sizeof(aarq_data_t));
+				aarq_data-> aarq_pending = FALSE;
+
+				/* insert aarq data */
+				se_tree_insert32(aarq_data_tree ,aircraft_24_bit_address,(void*)aarq_data);
+		}
+
+		/* check for pending AARQ/AARE sequences */
+		/* if "aarq_data-> aarq_pending" is set this means that there is already one  */
+		/* AARQ/AARE sequence pending (is unwise to overwrite AARE/AARQ) */
+		if (aarq_data-> aarq_pending == FALSE ) {
+
+			/* init aarq data */
+			memset(aarq_data,0,sizeof(aarq_data_t));
+
+			aarq_data->cv = atn_cv;
+			aarq_data-> aarq_pending = TRUE; 
+		}
+
+
+  return offset;
+}
+
+
+
+static int
+dissect_atn_ulcs_T_aare_apdu_protocol_version(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+  offset = dissect_per_bit_string(tvb, offset, actx, tree, hf_index,
+                                     NO_BOUND, NO_BOUND, FALSE, NULL);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Associate_result_vals[] = {
+  {   0, "accepted" },
+  {   1, "rejected-permanent" },
+  {   2, "rejected-transient" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_Associate_result(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+ /* extension present: last param set to true. asn2wrs didn't take notice of that */
+ offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
+                                                            0U, 2U, NULL, TRUE);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_T_acse_service_user_vals[] = {
+  {   0, "null" },
+  {   1, "no-reason-given" },
+  {   2, "application-context-name-not-supported" },
+  {   3, "calling-AP-title-not-recognized" },
+  {   4, "calling-AP-invocation-identifier-not-recognized" },
+  {   5, "calling-AE-qualifier-not-recognized" },
+  {   6, "calling-AE-invocation-identifier-not-recognized" },
+  {   7, "called-AP-title-not-recognized" },
+  {   8, "called-AP-invocation-identifier-not-recognized" },
+  {   9, "called-AE-qualifier-not-recognized" },
+  {  10, "called-AE-invocation-identifier-not-recognized" },
+  {  11, "authentication-mechanism-name-not-recognized" },
+  {  12, "authentication-mechanism-name-required" },
+  {  13, "authentication-failure" },
+  {  14, "authentication-required" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_T_acse_service_user(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, 14U, NULL, TRUE);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_T_acse_service_provider_vals[] = {
+  {   0, "null" },
+  {   1, "no-reason-given" },
+  {   2, "no-common-acse-version" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_T_acse_service_provider(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, 2U, NULL, TRUE);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Associate_source_diagnostic_vals[] = {
+  {   1, "acse-service-user" },
+  {   2, "acse-service-provider" },
+  { 0, NULL }
+};
+
+static const per_choice_t Associate_source_diagnostic_choice[] = {
+  {   1, &hf_atn_ulcs_acse_service_user, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_acse_service_user },
+  {   2, &hf_atn_ulcs_acse_service_provider, ASN1_NO_EXTENSIONS     , dissect_atn_ulcs_T_acse_service_provider },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_Associate_source_diagnostic(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_atn_ulcs_Associate_source_diagnostic, Associate_source_diagnostic_choice,
+                                 NULL);
+
+  return offset;
+}
+
+
+static const per_sequence_t AARE_apdu_sequence[] = {
+  { &hf_atn_ulcs_aare_apdu_protocol_version, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_T_aare_apdu_protocol_version },
+  { &hf_atn_ulcs_application_context_name, ASN1_EXTENSION_ROOT    , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_Application_context_name },
+  { &hf_atn_ulcs_result     , ASN1_EXTENSION_ROOT    , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_Associate_result },
+  { &hf_atn_ulcs_result_source_diagnostic, ASN1_EXTENSION_ROOT    , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_Associate_source_diagnostic },
+  { &hf_atn_ulcs_responding_AP_title, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AP_title },
+  { &hf_atn_ulcs_responding_AE_qualifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AE_qualifier },
+  { &hf_atn_ulcs_responding_AP_invocation_identifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AP_invocation_identifier },
+  { &hf_atn_ulcs_responding_AE_invocation_identifier, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_AE_invocation_identifier },
+  { &hf_atn_ulcs_responder_acse_requirements, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_ACSE_requirements },
+  { &hf_atn_ulcs_mechanism_name, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Mechanism_name },
+  { &hf_atn_ulcs_responding_authentication_value, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Authentication_value },
+  { &hf_atn_ulcs_application_context_name_list, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Application_context_name_list },
+  { &hf_atn_ulcs_implementation_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Implementation_data },
+  { &hf_atn_ulcs_user_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Association_information },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_AARE_apdu(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+	packet_info * pinfo = actx->pinfo;
+	guint32 aircraft_24_bit_address = 0 ;
+	atn_conversation_t *atn_cv = NULL;
+	aarq_data_t *aarq_data = NULL;
+	
+	/* get AARQ data and use it to create a new conversation, */
+	/* the conversation is used along with  */
+	/* AARQ's "calling ae qualifier" to determine the */
+	/* type of air/ground application of each subsequent frame.*/
+	/* we use this information to invoke the correct application dissector. */
+	/* note: */
+	/* heuristical decoding of ASN1 will not work for all cases, */
+	/* for there may be CM PDU's which will exactly look like CPDLC PDU'S */
+
+	/* get 24-bit icao address */
+	aircraft_24_bit_address = get_aircraft_24_bit_address_from_nsap(pinfo);
+	
+	/* search for aarq entry */
+	aarq_data = (aarq_data_t *) se_tree_lookup32(
+			aarq_data_tree,
+			aircraft_24_bit_address);
+
+	/* no aarq data present, do nothing  */
+	/* without both ends of the conversation and without */
+	/* the "calling ae-qualifier there is no point in setting up "*/
+	/* a conversation */
+	if(!aarq_data) {
+
+		return offset;
+	}
+
+	/* AARE/DT: dstref present, srcref is always zero */
+	if((pinfo->clnp_dstref) && (!pinfo->clnp_srcref)){
+
+		atn_cv = find_atn_conversation(&pinfo->dst,
+													pinfo->clnp_dstref,
+													&pinfo->src );
+
+		if(!atn_cv){ /* conversation not fond */
+
+			/* DT has only dstref - create new conversation */
+			create_atn_conversation(&pinfo->dst,
+															pinfo->clnp_dstref,
+															&pinfo->src ,
+															aarq_data->cv);
+		}
+	}
+
+	/* AARE/CC: srcref and dstref present  */
+	if((pinfo->clnp_dstref) && (pinfo->clnp_srcref)){
+
+		atn_cv = find_atn_conversation(
+				&pinfo->src,
+				pinfo->clnp_srcref,
+        &pinfo->dst);
+
+		if(atn_cv){ /* conversation found. */
+
+			/* create new conversation for dstref */
+			create_atn_conversation(&pinfo->dst,
+															pinfo->clnp_dstref,
+															&pinfo->src ,
+															aarq_data->cv);
+
+		}else { /* no conversation found  */
+			/* as CC contains srcref *and* dstref we use both to create new records  */
+			create_atn_conversation(&pinfo->src,
+															pinfo->clnp_srcref,
+															&pinfo->dst ,
+															aarq_data->cv);
+			create_atn_conversation(&pinfo->dst,
+															pinfo->clnp_dstref,
+															&pinfo->src ,
+															aarq_data->cv);
+		}
+	}
+
+	/* clear aarq data */
+	memset(aarq_data,0,sizeof(aarq_data_t));
+	aarq_data-> aarq_pending  =  FALSE;
+
+	  offset = dissect_per_sequence(tvb, offset, actx, tree, hf_index,
+                                   ett_atn_ulcs_AARE_apdu, AARE_apdu_sequence);
+
+
+
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Release_request_reason_vals[] = {
+  {   0, "normal" },
+  {   1, "urgent" },
+  {  30, "user-defined" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_Release_request_reason(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+ /* extension present: last param set to true. asn2wrs didn't take notice of that */
+ offset = dissect_per_constrained_integer(tvb, offset, actx, tree, hf_index,
+                                                            0U, 30U, NULL, TRUE);
+
+  return offset;
+}
+
+
+static const per_sequence_t RLRQ_apdu_sequence[] = {
+  { &hf_atn_ulcs_rlrq_apdu_request_reason, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Release_request_reason },
+  { &hf_atn_ulcs_user_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Association_information },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_RLRQ_apdu(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_atn_ulcs_RLRQ_apdu, RLRQ_apdu_sequence);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_Release_response_reason_vals[] = {
+  {   0, "normal" },
+  {   1, "not-finished" },
+  {  30, "user-defined" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_Release_response_reason(tvbuff_t *tvb _U_, int offset _U_, asn1_ctx_t *actx _U_, proto_tree *tree _U_, int hf_index _U_) {
+
+ /* extension present: last param set to true. asn2wrs didn't take notice of that */
+ offset = dissect_per_constrained_integer(
+		tvb,
+		offset,
+		actx,
+		tree,
+		hf_index,
+		0U,
+		30U,
+		NULL,
+		TRUE);
+
+
+  return offset;
+}
+
+
+static const per_sequence_t RLRE_apdu_sequence[] = {
+  { &hf_atn_ulcs_rlre_apdu_response_reason, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Release_response_reason },
+  { &hf_atn_ulcs_user_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Association_information },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_RLRE_apdu(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_atn_ulcs_RLRE_apdu, RLRE_apdu_sequence);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_ABRT_source_vals[] = {
+  {   0, "acse-service-user" },
+  {   1, "acse-service-provider" },
+  { 0, NULL }
+};
+
+
+static int
+dissect_atn_ulcs_ABRT_source(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, 1U, NULL, TRUE);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_ABRT_diagnostic_vals[] = {
+  {   1, "no-reason-given" },
+  {   2, "protocol-error" },
+  {   3, "authentication-mechanism-name-not-recognized" },
+  {   4, "authentication-mechanism-name-required" },
+  {   5, "authentication-failure" },
+  {   6, "authentication-required" },
+  { 0, NULL }
+};
+
+static guint32 ABRT_diagnostic_value_map[6+0] = {1, 2, 3, 4, 5, 6};
+
+static int
+dissect_atn_ulcs_ABRT_diagnostic(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,
+                                     6, NULL, TRUE, 0, ABRT_diagnostic_value_map);
+
+  return offset;
+}
+
+
+static const per_sequence_t ABRT_apdu_sequence[] = {
+  { &hf_atn_ulcs_abort_source, ASN1_EXTENSION_ROOT    , ASN1_NOT_OPTIONAL, dissect_atn_ulcs_ABRT_source },
+  { &hf_atn_ulcs_abort_diagnostic, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_ABRT_diagnostic },
+  { &hf_atn_ulcs_user_information, ASN1_EXTENSION_ROOT    , ASN1_OPTIONAL    , dissect_atn_ulcs_Association_information },
+  { NULL, 0, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_ABRT_apdu(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_atn_ulcs_ABRT_apdu, ABRT_apdu_sequence);
+
+  return offset;
+}
+
+
+static const value_string atn_ulcs_ACSE_apdu_vals[] = {
+  {   0, "aarq" },
+  {   1, "aare" },
+  {   2, "rlrq" },
+  {   3, "rlre" },
+  {   4, "abrt" },
+  { 0, NULL }
+};
+
+static const per_choice_t ACSE_apdu_choice[] = {
+  {   0, &hf_atn_ulcs_aarq       , ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_AARQ_apdu },
+  {   1, &hf_atn_ulcs_aare       , ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_AARE_apdu },
+  {   2, &hf_atn_ulcs_rlrq       , ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_RLRQ_apdu },
+  {   3, &hf_atn_ulcs_rlre       , ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_RLRE_apdu },
+  {   4, &hf_atn_ulcs_abrt       , ASN1_EXTENSION_ROOT    , dissect_atn_ulcs_ABRT_apdu },
+  { 0, NULL, 0, NULL }
+};
+
+static int
+dissect_atn_ulcs_ACSE_apdu(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_atn_ulcs_ACSE_apdu, ACSE_apdu_choice,
+                                 NULL);
+
+  return offset;
+}
+
+/*--- PDUs ---*/
+
+static void dissect_Fully_encoded_data_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_) {
+  asn1_ctx_t asn1_ctx;
+  asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, FALSE, pinfo);
+  dissect_atn_ulcs_Fully_encoded_data(tvb, 0, &asn1_ctx, tree, hf_atn_ulcs_Fully_encoded_data_PDU);
+}
+static void dissect_ACSE_apdu_PDU(tvbuff_t *tvb _U_, packet_info *pinfo _U_, proto_tree *tree _U_) {
+  asn1_ctx_t asn1_ctx;
+  asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, FALSE, pinfo);
+  dissect_atn_ulcs_ACSE_apdu(tvb, 0, &asn1_ctx, tree, hf_atn_ulcs_ACSE_apdu_PDU);
+}
+
+
+/*--- End of included file: packet-atn-ulcs-fn.c ---*/
+#line 202 "../../asn1/atn-ulcs/packet-atn-ulcs-template.c"
+
+/* re-implementing external data: packet-per.c */
+static const value_string per_External_encoding_vals[] = {
+{   0, "single-ASN1-type" },
+{   1, "octet-aligned" },
+{   2, "arbitrary" },
+{ 0, NULL }
+};
+
+/* re-implementing external data: packet-per.c */
+static const per_choice_t External_encoding_choice[] =
+{
+		{		0,
+				&hf_atn_ulcs_externalt_encoding_single_asn1_type,
+				ASN1_NO_EXTENSIONS,
+				dissect_atn_ulcs_T_externalt_encoding_single_asn1_type
+		},
+		{		1,
+				&hf_atn_ulcs_externalt_encoding_octet_aligned,
+				ASN1_NO_EXTENSIONS,
+				dissect_atn_ulcs_T_externalt_encoding_octet_aligned
+		},
+		{		2,
+				&hf_atn_ulcs_externalt_encoding_arbitrary,
+				ASN1_NO_EXTENSIONS,
+				dissect_atn_ulcs_T_externalt_encoding_arbitrary
+		},
+		{		0,
+				NULL,
+				0,
+				NULL
+		}
+};
+
+/* ATN Session layer */
+#define SES_PDU_TYPE_MASK			0xf8
+#define SES_PARAM_IND_MASK		0x04 
+#define SES_PARAM_B2_MASK			0x02
+#define SES_PARAM_B1_MASK			0x01
+
+static int hf_atn_ses_type = -1;
+static int hf_atn_ses_param_ind = -1;
+static int hf_atn_ses_param_b1 = -1;
+static int hf_atn_ses_param_b2 = -1;
+
+static gint ett_atn_ses = -1;
+
+#define ATN_SES_PROTO "ICAO Doc9705 ULCS Session (ISO 8326/8327-1:1994)"
+
+const value_string atn_ses_param_ind[] =
+{
+		{0,	"No Parameter Indication "},
+		{1,	"Parameter Indication "},
+		{0,	NULL }
+};
+
+const value_string srf_b2[] =
+{
+		{0,	"Transport Connection is kept"},
+		{1,	"Transport Connection is released" },
+		{0,	NULL }
+};
+
+const value_string srf_b1[] =
+{
+		{0,	"Transport Connection is transient"},
+		{1,	"Transport Connection is persistent"},
+		{0,	NULL }
+};
+
+#define SES_ATN_SCN				0xe8
+#define SES_ATN_SCNC			0xf8
+#define SES_ATN_SAC				0xf0
+#define SES_ATN_SACC			0xd8
+#define SES_ATN_SRF				0xe0
+#define SES_ATN_SRFC			0xa0
+
+const value_string atn_ses_type[] =
+{
+		{ 0x1d,	"Short Connect (SCN) SPDU" },
+		{ 0x1f,	"Short Connect Accept (SAC) SPDU" },
+		{ 0x1e,	"Short Connect Accept Continue (SACC) SPDU" },
+		{ 0x1c,	"Short Refuse (SRF) SPDU" },
+		{ 0x14,	"Short Refuse Continue (SRFC) SPDU" },
+		{0,	NULL }
+};
+
+/* ATN Presentation layer */
+#define ATN_PRES_PROTO "ICAO Doc9705 ULCS Presentation (ISO 8822/8823-1:1994)"
+
+static int hf_atn_pres_err	 = -1;
+static gint ett_atn_pres		= -1;
+
+#define ATN_SES_PRES_MASK 0xf803
+#define PRES_CPR_ER_MASK		0x70
+
+/* type determined by SPDU and PPDU */
+const value_string atn_pres_vals[] =
+{
+		{ 0xe802, "Short Presentation Connect PPDU (CP) " },
+		{ 0xf802, "Short Presentation Connect PPDU (CP) " },
+		{ 0xf002, "Short Presentation Connect Accept PPDU (CPA)" },
+		{ 0xd802, "Short Presentation Connect Accept PPDU (CPA)" },
+		{ 0xe002, "Short Presentation Connect Reject PPDU (CPR)" },
+		{ 0xa002, "Short Presentation Connect Reject PPDU (CPR)" },
+		{0,					NULL }
+};
+
+/* Short Presentation Connect Reject PPDU's 0yyy 00zz */
+const value_string atn_pres_err[] =
+{
+		{ 0x00, "Presentation-user" },
+		{ 0x01, "Reason not specified (transient)"},
+		{ 0x02,	"Temporary congestion (transient)"},
+		{ 0x03,	"Local limit exceeded (transient)"},
+		{ 0x04, "Called presentation-address unknown (permanent)"},
+		{ 0x05,	"Protocol version not supported (permanent)"},
+		{ 0x06,	"Default context not supported (permanent)"},
+		{ 0x07,	"User data not readable (permanent)"},
+		{ 0,					NULL }
+};
+
+/* re-implementing external data: packet-per.c */
+static int	atn_ulcs_Externalt_encoding(
+		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_atn_ulcs_EXTERNALt,
+				External_encoding_choice,
+				&actx->external.encoding);
+
+		return offset;
+}
+
+/* re-implementing external data: packet-per.c */
+guint32	atn_per_external_type(
+		tvbuff_t *tvb _U_,
+		guint32 offset,
+		asn1_ctx_t *actx,
+		proto_tree *tree _U_,
+		int hf_index _U_,
+		per_type_fn type_cb)
+{
+		memset(&actx->external, '\0', sizeof(actx->external));
+		actx->external.hf_index = -1;
+		actx->external.encoding = -1;
+
+		actx->external.u.per.type_cb = type_cb;
+		offset = atn_ulcs_Externalt_encoding(
+				tvb,
+				offset,
+				actx,
+				tree,
+				hf_index);
+
+		memset(
+				&actx->external,
+				'\0',
+				sizeof(actx->external));
+				
+		actx->external.hf_index = -1;
+		actx->external.encoding = -1;
+
+		return offset;
+}
+
+/* determine 24-bit aircraft address(ARS) */
+/* from 20-byte ATN NSAP. */
+guint32 get_aircraft_24_bit_address_from_nsap(
+		packet_info *pinfo)
+{
+		guint8* addr = NULL;
+		guint32 ars =0;
+		guint32 adr_prefix =0;
+	
+		/* check NSAP address type*/
+		if( (pinfo->src.type != AT_OSI) ||
+				(pinfo->dst.type != AT_OSI)) {
+				return ars; }
+
+		/* 20 octets address length required */
+		/* for ATN */
+		if( (pinfo->src.len != 20) ||
+				(pinfo->dst.len != 20)) {
+				return ars; }
+
+		/* first try source address */
+		/* if the src address originates */
+		/* from an aircraft it's downlink */
+		
+		/* convert addr into 32-bit integer */
+		addr = (guint8*) pinfo->src.data;
+		adr_prefix =
+				((addr[0]<<24) |
+				(addr[1]<<16) |
+				(addr[2]<<8) |
+				addr[3] );
+
+		/* according to ICAO doc9507 Ed2 SV5  */
+		/* clause 5.4.3.8.1.5 and  5.4.3.8.1.3 */
+		/* mobile addresses contain "c1" of "41" */
+		/* in the VER subfield of the NSAP */
+		if((adr_prefix == 0x470027c1) ||
+				(adr_prefix == 0x47002741)) {
+			/* ICAO doc9507 Ed2 SV5 5.4.3.8.4.4 */
+			/* states that the ARS subfield containes */
+			/* the  24-bitaddress of the aircraft */
+				ars = ((addr[8])<<16) |
+						((addr[9])<<8) |
+						(addr[10]);
+		}
+
+		/* try destination address */
+		/* if the src address originates */
+		/* from an aircraft it's downlink */
+
+		/* convert addr into 32-bit integer */
+		addr = (guint8*) pinfo->dst.data;
+		adr_prefix = ((addr[0]<<24) |
+				(addr[1]<<16) |
+				(addr[2]<<8) |
+				addr[3] );
+				
+		/* according to ICAO doc9507 Ed2 SV5  */
+		/* clause 5.4.3.8.1.5 and  5.4.3.8.1.3 */
+		/* mobile addresses contain "c1" of "41" */
+		/* in the VER subfield of the NSAP */
+		if((adr_prefix == 0x470027c1) ||
+				(adr_prefix == 0x47002741)) {
+			/* ICAO doc9507 Ed2 SV5 5.4.3.8.4.4 */
+			/* states that the ARS subfield containes */
+			/* the  24-bitaddress of the aircraft */
+			ars = ((addr[8])<<16) |
+						((addr[9])<<8) |
+						(addr[10]);
+		}
+		return ars;
+}
+
+/* determine whether a PDU is uplink or downlink */
+/* by checking for known aircraft  address prefices*/
+int check_heur_msg_type(packet_info *pinfo  _U_)
+{
+		int t = no_msg;
+		guint8* addr = NULL;
+		guint32 adr_prefix =0;
+	
+		/* check NSAP address type*/
+		if( (pinfo->src.type != AT_OSI) || (pinfo->dst.type != AT_OSI)) {
+				return t; }
+
+		/* check NSAP address length; 20 octets address length required */
+		if( (pinfo->src.len != 20) || (pinfo->dst.len != 20)) {
+				return t; }
+	
+		addr = (guint8*) pinfo->src.data;
+
+		/* convert address to 32-bit integer  */
+		adr_prefix = ((addr[0]<<24) | (addr[1]<<16) | (addr[2]<<8) | addr[3] );
+
+		/* According to the published ATN NSAP adddressing scheme */
+		/* in ICAO doc9705 Ed2 SV5 5.4.3.8.1.3 and 5.4.3.8.1.5  */
+		/* the "VER" field shall be 0x41 ("all Mobile AINSC") or */
+		/* 0xc1 ("all Mobile ATSC") for mobile stations (aka aircraft).*/
+		if((adr_prefix == 0x470027c1) || (adr_prefix == 0x47002741)) {
+				t = dm; /* source is an aircraft: it's a downlink PDU */
+		}
+		
+		addr = (guint8*) pinfo->dst.data;
+
+		/* convert address to 32-bit integer  */
+		adr_prefix = ((addr[0]<<24) | (addr[1]<<16) | (addr[2]<<8) | addr[3] );
+
+		/* According to the published ATN NSAP adddressing scheme */
+		/* in ICAO doc9705 Ed2 SV5 5.4.3.8.1.3 and 5.4.3.8.1.5  */
+		/* the "VER" field shall be 0x41 ("all Mobile AINSC") or */
+		/* 0xc1 ("all Mobile ATSC") for mobile stations (aka aircraft).*/
+		if((adr_prefix == 0x470027c1) || (adr_prefix == 0x47002741)) {
+				t = um; /* destination is aircraft: uplink PDU */
+		}		
+
+		return t;
+}
+
+/* conversation may be used by other dissectors  */
+emem_tree_t *get_atn_conversation_tree(void){
+		return atn_conversation_tree;
+}
+
+
+/* find a atn conversation tree node by an endpoint  */
+/* an endpoint is identified by atn src and dst addresses */
+/* and srcref or dstref (depends on the transport packet type) */
+/* IMHO it's a hack - conversations should be maintained */
+/* at transport layer (cotp) but this isn't working yet. */
+atn_conversation_t * find_atn_conversation(
+		address *address1,
+		guint16 clnp_ref1,
+		address *address2 )
+{
+		atn_conversation_t *cv = NULL;
+		guint32	key = 0;
+		guint32	tmp = 0;
+
+		ADD_ADDRESS_TO_HASH( tmp, address1);
+		key = (tmp << 16) | clnp_ref1 ;
+
+		ADD_ADDRESS_TO_HASH( tmp, address2);
+		key = (tmp << 24) | key ;
+
+		/* search for atn conversation */
+		cv = (atn_conversation_t *)
+				se_tree_lookup32(get_atn_conversation_tree(),key);
+	
+		return cv;
+}
+
+/* create a atn conversation tree node  */
+/* conversation data is to be allocated externally */
+/* a conversation may be referenced from both endpoints */
+atn_conversation_t * create_atn_conversation(
+		address *address1,
+		guint16 clnp_ref1,
+		address *address2,
+		atn_conversation_t *conversation)
+{
+		atn_conversation_t *cv = NULL;
+		guint32	key = 0;
+		guint32	tmp = 0;
+
+		ADD_ADDRESS_TO_HASH( tmp, address1);
+		key = (tmp << 16) | clnp_ref1 ;
+
+		ADD_ADDRESS_TO_HASH( tmp, address2);
+		key = (tmp << 24) | key ;
+
+		/* search for aircraft entry */
+		cv = (atn_conversation_t *)
+		se_tree_lookup32(
+				get_atn_conversation_tree(),
+				key);
+
+		/* tree node  already present  */
+		if(cv) {
+			return NULL; }
+			
+		/* insert conversation data in tree*/
+		se_tree_insert32(
+				get_atn_conversation_tree(),
+				key,
+				(void*)conversation);
+
+		return conversation;
+}
+
+static int
+dissect_atn_ulcs(
+		tvbuff_t *tvb,
+		packet_info *pinfo,
+		proto_tree *tree,
+		void *data _U_)
+{
+		int offset = 0;
+		proto_item *ti = NULL;
+		proto_tree *atn_ulcs_tree = NULL;
+		guint8 value_pres = 0;
+		guint8 value_ses = 0;
+		guint16 value_ses_pres = 0; 
+
+		root_tree = tree;
+
+		/* data pointer */
+		/* decode as PDV-list */
+		if ( (int)(intptr_t)  data == FALSE )
+		{
+				ti = proto_tree_add_item(
+						tree,
+						proto_atn_ulcs,
+						tvb,
+						0,
+						0 ,
+						FALSE);
+						
+				atn_ulcs_tree = proto_item_add_subtree(
+						ti,
+						ett_atn_ulcs);
+		
+				dissect_Fully_encoded_data_PDU(
+						tvb,
+						pinfo,
+						atn_ulcs_tree);
+						
+				return offset +
+					tvb_reported_length_remaining(tvb, offset ) ;
+		}
+		
+		/* decode as SPDU, PPDU and ACSE PDU */
+		if ( (int)(intptr_t)  data == TRUE )
+		{
+				/* get session and presentation PDU's */
+				value_ses_pres = tvb_get_ntohs(tvb, offset);
+		
+				/* SPDU: dissect session layer */
+				ti = proto_tree_add_text(
+						tree,
+						tvb,
+						offset,
+						0,
+						ATN_SES_PROTO );
+
+				atn_ulcs_tree = proto_item_add_subtree(
+						ti,
+						ett_atn_ses);
+
+				/* get SPDU (1 octet) */
+				value_ses = tvb_get_guint8(tvb, offset);
+
+				/* SPDU type/identifier  */
+				proto_tree_add_item(atn_ulcs_tree,
+						hf_atn_ses_type,
+						tvb,
+						offset,
+						1,
+						ENC_BIG_ENDIAN );
+
+				/* SPDU parameters may be present in Short Refuse */
+				/* or Short Refuse Continue SPDU's */
+				switch(value_ses & SES_PDU_TYPE_MASK){
+						case SES_ATN_SRF:
+						case SES_ATN_SRFC:
+
+								/* SPDU parameter presence */
+								proto_tree_add_item(atn_ulcs_tree,
+										hf_atn_ses_param_ind,
+										tvb,
+										offset,
+										1,
+										ENC_BIG_ENDIAN );
+
+								/* parameter B2 */
+								proto_tree_add_item(atn_ulcs_tree,
+										hf_atn_ses_param_b2,
+										tvb,
+										offset,
+										1,
+										ENC_BIG_ENDIAN );
+
+								/* parameter B1 */
+								proto_tree_add_item(atn_ulcs_tree,
+										hf_atn_ses_param_b1,
+										tvb,
+										offset,
+										1,
+										ENC_BIG_ENDIAN );
+
+							break;
+						default:
+							break;
+				}
+				offset++;
+		
+				/* PPDU: dissect presentation layer */
+				ti = proto_tree_add_text(
+						tree,
+						tvb,
+						offset,
+						0,
+						ATN_PRES_PROTO );
+						
+				atn_ulcs_tree = proto_item_add_subtree(ti, ett_atn_pres);
+
+				value_pres = tvb_get_guint8(tvb, offset);
+
+				/* need session context to identify PPDU type */
+				/* note: */
+				/* it is *unfeasible* to use proto_tree_add_item here: */
+				/* presentation type is always the same constant but its type */
+				/* is implicitly determined by preceding session context */
+				proto_tree_add_text(atn_ulcs_tree,
+						tvb,
+						offset,
+						1,
+						"%s (0x%02x)",
+						val_to_str( value_ses_pres & ATN_SES_PRES_MASK , atn_pres_vals, "?"),
+						value_pres);
+			
+				/* PPDU errorcode in case of SRF/CPR */
+				switch(value_ses & SES_PDU_TYPE_MASK){
+						case SES_ATN_SRF:
+						case SES_ATN_SRFC:
+								proto_tree_add_item(
+										atn_ulcs_tree,
+										hf_atn_pres_err,
+										tvb,
+										offset,
+										1,
+										ENC_BIG_ENDIAN );
+								break;
+						default:
+								break;
+				}
+
+				offset++;
+
+				/* ACSE PDU: dissect application layer */
+				ti = proto_tree_add_text(
+						tree,
+						tvb,
+						offset,
+						0,
+						ATN_ACSE_PROTO );
+				
+				atn_ulcs_tree = proto_item_add_subtree(
+						ti,
+						ett_atn_acse);
+
+				dissect_ACSE_apdu_PDU(
+						tvb_new_subset_remaining(tvb, offset),
+						pinfo,
+						atn_ulcs_tree);
+
+				return offset +
+						tvb_reported_length_remaining(tvb, offset );
+		}
+		return offset;
+}
+
+static gboolean dissect_atn_ulcs_heur(
+		tvbuff_t *tvb,
+		packet_info *pinfo,
+		proto_tree *tree,
+		void *data _U_)
+{	
+		/* do we have enough data*/
+		/* at least session + presentation data or pdv-list */
+		if (tvb_reported_length_remaining(tvb, 0) < 2){
+				return FALSE; }
+	
+		/* check for session/presentation/ACSE PDU's  */
+		/* SPDU and PPDU are one octet each */
+		switch( tvb_get_ntohs(tvb, 0) & 0xf8ff ){
+				case 0xe802: /* SCN + CP*/
+				case 0xf802: /* SCNC + CP */
+				case 0xf002: /* SAC + CPA */
+				case 0xd802: /* SACC + CPA */
+				case 0xe002: /* SRF + CPR + R0 */
+				case 0xe012: /* SRF + CPR + R1 */
+				case 0xe022: /* SRF + CPR + R2 */
+				case 0xe032: /* SRF + CPR + R3 */
+				case 0xe042: /* SRF + CPR + R4 */
+				case 0xe052: /* SRF + CPR + R5 */
+				case 0xe062: /* SRF + CPR + R6 */
+				case 0xe072: /* SRF + CPR + R7 */
+				case 0xa002: /* SRFC + CPR + R0*/
+				case 0xa012: /* SRFC + CPR + R1*/
+				case 0xa022: /* SRFC + CPR + R2*/
+				case 0xa032: /* SRFC + CPR + R3*/
+				case 0xa042: /* SRFC + CPR + R4*/
+				case 0xa052: /* SRFC + CPR + R5*/
+				case 0xa062: /* SRFC + CPR + R6*/
+				case 0xa072: /* SRFC + CPR + R7*/
+						/* indicate to dissector routine */
+						/* that a least SPDU, PPDU and */
+						/* ACSE PDU is present */
+						dissect_atn_ulcs(
+								tvb,
+								pinfo,
+								tree,
+								(void*) TRUE);
+						return TRUE;
+				default:	/* no SPDU */
+						break;
+		}
+
+		/* try to detect "Fully-encoded-data" heuristically */
+		/* the constants listed match the ASN.1 PER encoding */
+		/* of PDV-List */
+		switch(  tvb_get_ntohs(tvb, 0) & 0xfff0 ){
+				case 0x0020: /* acse-apdu */
+				case 0x00a0: /* user-ase-apdu */
+				/* indicate to dissector routine */
+				/* that a PDV-list PDU is present */
+				/*  */
+				/* PDV-list PDU may contain */
+				/* application protocol data (CM, CPDLC) */
+				/* or an ACSE PDU */
+						dissect_atn_ulcs(tvb, pinfo, tree, (void*) FALSE);
+						return TRUE;
+						break;
+				default:	/* no or unsupported PDU */
+						break;
+		}
+		return FALSE;
+}
+
+void proto_register_atn_ulcs (void)
+{
+		static hf_register_info hf_atn_ulcs[] = {
+
+/*--- Included file: packet-atn-ulcs-hfarr.c ---*/
+#line 1 "../../asn1/atn-ulcs/packet-atn-ulcs-hfarr.c"
+    { &hf_atn_ulcs_Fully_encoded_data_PDU,
+      { "Fully-encoded-data", "atn-ulcs.Fully_encoded_data",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ACSE_apdu_PDU,
+      { "ACSE-apdu", "atn-ulcs.ACSE_apdu",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_ACSE_apdu_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_Fully_encoded_data_item,
+      { "PDV-list", "atn-ulcs.PDV_list_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_transfer_syntax_name,
+      { "transfer-syntax-name", "atn-ulcs.transfer_syntax_name",
+        FT_OID, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_presentation_context_identifier,
+      { "presentation-context-identifier", "atn-ulcs.presentation_context_identifier",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Presentation_context_identifier_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_presentation_data_values,
+      { "presentation-data-values", "atn-ulcs.presentation_data_values",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_T_presentation_data_values_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_pdv_list_presentation_data_values_single_asn1_type,
+      { "single-ASN1-type", "atn-ulcs.single_ASN1_type_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "T_pdv_list_presentation_data_values_single_asn1_type", HFILL }},
+    { &hf_atn_ulcs_octet_aligned,
+      { "octet-aligned", "atn-ulcs.octet_aligned",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "OCTET_STRING", HFILL }},
+    { &hf_atn_ulcs_pdv_list_presentation_data_values_arbitrary,
+      { "arbitrary", "atn-ulcs.arbitrary",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "T_pdv_list_presentation_data_values_arbitrary", HFILL }},
+    { &hf_atn_ulcs_direct_reference,
+      { "direct-reference", "atn-ulcs.direct_reference",
+        FT_OID, BASE_NONE, NULL, 0,
+        "OBJECT_IDENTIFIER", HFILL }},
+    { &hf_atn_ulcs_indirect_reference,
+      { "indirect-reference", "atn-ulcs.indirect_reference",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "INTEGER", HFILL }},
+    { &hf_atn_ulcs_data_value_descriptor,
+      { "data-value-descriptor", "atn-ulcs.data_value_descriptor",
+        FT_STRING, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_encoding,
+      { "encoding", "atn-ulcs.encoding",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_T_encoding_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_externalt_encoding_single_asn1_type,
+      { "single-ASN1-type", "atn-ulcs.single_ASN1_type_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "T_externalt_encoding_single_asn1_type", HFILL }},
+    { &hf_atn_ulcs_externalt_encoding_octet_aligned,
+      { "octet-aligned", "atn-ulcs.octet_aligned",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "T_externalt_encoding_octet_aligned", HFILL }},
+    { &hf_atn_ulcs_externalt_encoding_arbitrary,
+      { "arbitrary", "atn-ulcs.arbitrary",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "T_externalt_encoding_arbitrary", HFILL }},
+    { &hf_atn_ulcs_aarq,
+      { "aarq", "atn-ulcs.aarq_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "AARQ_apdu", HFILL }},
+    { &hf_atn_ulcs_aare,
+      { "aare", "atn-ulcs.aare_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "AARE_apdu", HFILL }},
+    { &hf_atn_ulcs_rlrq,
+      { "rlrq", "atn-ulcs.rlrq_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "RLRQ_apdu", HFILL }},
+    { &hf_atn_ulcs_rlre,
+      { "rlre", "atn-ulcs.rlre_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "RLRE_apdu", HFILL }},
+    { &hf_atn_ulcs_abrt,
+      { "abrt", "atn-ulcs.abrt_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        "ABRT_apdu", HFILL }},
+    { &hf_atn_ulcs_aarq_apdu_protocol_version,
+      { "protocol-version", "atn-ulcs.protocol_version",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "T_aarq_apdu_protocol_version", HFILL }},
+    { &hf_atn_ulcs_application_context_name,
+      { "application-context-name", "atn-ulcs.application_context_name",
+        FT_OID, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_called_AP_title,
+      { "called-AP-title", "atn-ulcs.called_AP_title",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_AP_title_vals), 0,
+        "AP_title", HFILL }},
+    { &hf_atn_ulcs_called_AE_qualifier,
+      { "called-AE-qualifier", "atn-ulcs.called_AE_qualifier",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_AE_qualifier_vals), 0,
+        "AE_qualifier", HFILL }},
+    { &hf_atn_ulcs_called_AP_invocation_identifier,
+      { "called-AP-invocation-identifier", "atn-ulcs.called_AP_invocation_identifier",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "AP_invocation_identifier", HFILL }},
+    { &hf_atn_ulcs_called_AE_invocation_identifier,
+      { "called-AE-invocation-identifier", "atn-ulcs.called_AE_invocation_identifier",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "AE_invocation_identifier", HFILL }},
+    { &hf_atn_ulcs_calling_AP_title,
+      { "calling-AP-title", "atn-ulcs.calling_AP_title",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_AP_title_vals), 0,
+        "AP_title", HFILL }},
+    { &hf_atn_ulcs_calling_AE_qualifier,
+      { "calling-AE-qualifier", "atn-ulcs.calling_AE_qualifier",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_AE_qualifier_vals), 0,
+        "AE_qualifier", HFILL }},
+    { &hf_atn_ulcs_calling_AP_invocation_identifier,
+      { "calling-AP-invocation-identifier", "atn-ulcs.calling_AP_invocation_identifier",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "AP_invocation_identifier", HFILL }},
+    { &hf_atn_ulcs_calling_AE_invocation_identifier,
+      { "calling-AE-invocation-identifier", "atn-ulcs.calling_AE_invocation_identifier",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "AE_invocation_identifier", HFILL }},
+    { &hf_atn_ulcs_sender_acse_requirements,
+      { "sender-acse-requirements", "atn-ulcs.sender_acse_requirements",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "ACSE_requirements", HFILL }},
+    { &hf_atn_ulcs_mechanism_name,
+      { "mechanism-name", "atn-ulcs.mechanism_name",
+        FT_OID, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_calling_authentication_value,
+      { "calling-authentication-value", "atn-ulcs.calling_authentication_value",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Authentication_value_vals), 0,
+        "Authentication_value", HFILL }},
+    { &hf_atn_ulcs_application_context_name_list,
+      { "application-context-name-list", "atn-ulcs.application_context_name_list",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_implementation_information,
+      { "implementation-information", "atn-ulcs.implementation_information",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "Implementation_data", HFILL }},
+    { &hf_atn_ulcs_user_information,
+      { "user-information", "atn-ulcs.user_information",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        "Association_information", HFILL }},
+    { &hf_atn_ulcs_aare_apdu_protocol_version,
+      { "protocol-version", "atn-ulcs.protocol_version",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "T_aare_apdu_protocol_version", HFILL }},
+    { &hf_atn_ulcs_result,
+      { "result", "atn-ulcs.result",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Associate_result_vals), 0,
+        "Associate_result", HFILL }},
+    { &hf_atn_ulcs_result_source_diagnostic,
+      { "result-source-diagnostic", "atn-ulcs.result_source_diagnostic",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Associate_source_diagnostic_vals), 0,
+        "Associate_source_diagnostic", HFILL }},
+    { &hf_atn_ulcs_responding_AP_title,
+      { "responding-AP-title", "atn-ulcs.responding_AP_title",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_AP_title_vals), 0,
+        "AP_title", HFILL }},
+    { &hf_atn_ulcs_responding_AE_qualifier,
+      { "responding-AE-qualifier", "atn-ulcs.responding_AE_qualifier",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_AE_qualifier_vals), 0,
+        "AE_qualifier", HFILL }},
+    { &hf_atn_ulcs_responding_AP_invocation_identifier,
+      { "responding-AP-invocation-identifier", "atn-ulcs.responding_AP_invocation_identifier",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "AP_invocation_identifier", HFILL }},
+    { &hf_atn_ulcs_responding_AE_invocation_identifier,
+      { "responding-AE-invocation-identifier", "atn-ulcs.responding_AE_invocation_identifier",
+        FT_INT32, BASE_DEC, NULL, 0,
+        "AE_invocation_identifier", HFILL }},
+    { &hf_atn_ulcs_responder_acse_requirements,
+      { "responder-acse-requirements", "atn-ulcs.responder_acse_requirements",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "ACSE_requirements", HFILL }},
+    { &hf_atn_ulcs_responding_authentication_value,
+      { "responding-authentication-value", "atn-ulcs.responding_authentication_value",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Authentication_value_vals), 0,
+        "Authentication_value", HFILL }},
+    { &hf_atn_ulcs_rlrq_apdu_request_reason,
+      { "reason", "atn-ulcs.reason",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Release_request_reason_vals), 0,
+        "Release_request_reason", HFILL }},
+    { &hf_atn_ulcs_rlre_apdu_response_reason,
+      { "reason", "atn-ulcs.reason",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Release_response_reason_vals), 0,
+        "Release_response_reason", HFILL }},
+    { &hf_atn_ulcs_abort_source,
+      { "abort-source", "atn-ulcs.abort_source",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_ABRT_source_vals), 0,
+        "ABRT_source", HFILL }},
+    { &hf_atn_ulcs_abort_diagnostic,
+      { "abort-diagnostic", "atn-ulcs.abort_diagnostic",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_ABRT_diagnostic_vals), 0,
+        "ABRT_diagnostic", HFILL }},
+    { &hf_atn_ulcs_Application_context_name_list_item,
+      { "Application-context-name", "atn-ulcs.Application_context_name",
+        FT_OID, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ap_title_form2,
+      { "ap-title-form2", "atn-ulcs.ap_title_form2",
+        FT_OID, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ap_title_form1,
+      { "ap-title-form1", "atn-ulcs.ap_title_form1",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_Name_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ae_qualifier_form2,
+      { "ae-qualifier-form2", "atn-ulcs.ae_qualifier_form2",
+        FT_INT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ae_qualifier_form1,
+      { "ae-qualifier-form1", "atn-ulcs.ae_qualifier_form1",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_acse_service_user,
+      { "acse-service-user", "atn-ulcs.acse_service_user",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_T_acse_service_user_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_acse_service_provider,
+      { "acse-service-provider", "atn-ulcs.acse_service_provider",
+        FT_UINT32, BASE_DEC, VALS(atn_ulcs_T_acse_service_provider_vals), 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_Association_information_item,
+      { "EXTERNALt", "atn-ulcs.EXTERNALt_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_charstring,
+      { "charstring", "atn-ulcs.charstring",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "OCTET_STRING", HFILL }},
+    { &hf_atn_ulcs_bitstring,
+      { "bitstring", "atn-ulcs.bitstring",
+        FT_BYTES, BASE_NONE, NULL, 0,
+        "BIT_STRING", HFILL }},
+    { &hf_atn_ulcs_external,
+      { "external", "atn-ulcs.external_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_other,
+      { "other", "atn-ulcs.other_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_other_mechanism_name,
+      { "other-mechanism-name", "atn-ulcs.other_mechanism_name",
+        FT_OID, BASE_NONE, NULL, 0,
+        "OBJECT_IDENTIFIER", HFILL }},
+    { &hf_atn_ulcs_other_mechanism_value,
+      { "other-mechanism-value", "atn-ulcs.other_mechanism_value_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_rdnSequence,
+      { "rdnSequence", "atn-ulcs.rdnSequence",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_RDNSequence_item,
+      { "RelativeDistinguishedName", "atn-ulcs.RelativeDistinguishedName",
+        FT_UINT32, BASE_DEC, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_RelativeDistinguishedName_item,
+      { "AttributeTypeAndValue", "atn-ulcs.AttributeTypeAndValue_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_null,
+      { "null", "atn-ulcs.null_element",
+        FT_NONE, BASE_NONE, NULL, 0,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_T_aarq_apdu_protocol_version_version1,
+      { "version1", "atn-ulcs.version1",
+        FT_BOOLEAN, 8, NULL, 0x80,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_T_aare_apdu_protocol_version_version1,
+      { "version1", "atn-ulcs.version1",
+        FT_BOOLEAN, 8, NULL, 0x80,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ACSE_requirements_authentication,
+      { "authentication", "atn-ulcs.authentication",
+        FT_BOOLEAN, 8, NULL, 0x80,
+        NULL, HFILL }},
+    { &hf_atn_ulcs_ACSE_requirements_application_context_negotiation,
+      { "application-context-negotiation", "atn-ulcs.application-context-negotiation",
+        FT_BOOLEAN, 8, NULL, 0x40,
+        NULL, HFILL }},
+
+/*--- End of included file: packet-atn-ulcs-hfarr.c ---*/
+#line 810 "../../asn1/atn-ulcs/packet-atn-ulcs-template.c"
+				{&hf_atn_ses_type,
+				{ "SPDU Type",
+					"atn-ulcs.ses.type",
+					FT_UINT8,
+					BASE_HEX,
+					VALS(atn_ses_type),
+					0xf8,
+					"Indicates presence of session parameters",
+					HFILL}},
+				{&hf_atn_ses_param_ind,
+				{ "SPDU Parameter Indication",
+					"atn-ulcs.ses.parameter-indication",
+					FT_UINT8,
+					BASE_HEX,
+					VALS(atn_ses_param_ind),
+					SES_PARAM_IND_MASK,
+					"Indicates presence of session parameters",
+					HFILL}},
+			{&hf_atn_ses_param_b1,
+				{ "SRF Parameter B1",
+					"atn-ulcs.ses.srf-b1",
+					FT_UINT8,
+					BASE_HEX,
+					VALS(srf_b1),
+					0x01,
+					"Determines if transport connection reject is \
+					transient or persistent",
+					HFILL}},
+			{&hf_atn_ses_param_b2,
+				{ "SRF Parameter B2",
+					"atn-ulcs.ses.srf-b2",
+					FT_UINT8,
+					BASE_HEX,
+					VALS(srf_b2),
+					0x02,
+					"Determines if transport connection is \
+					retained or released",
+					HFILL}},
+			{ &hf_atn_pres_err,
+				{ "Error Code", "atn-ulcs.pres.cpr-error",
+					FT_UINT8,
+					BASE_HEX,
+					VALS(atn_pres_err),
+					PRES_CPR_ER_MASK,
+					NULL,
+					HFILL}},
+		};
+		
+		static gint *ett[] = {
+
+/*--- Included file: packet-atn-ulcs-ettarr.c ---*/
+#line 1 "../../asn1/atn-ulcs/packet-atn-ulcs-ettarr.c"
+    &ett_atn_ulcs_Fully_encoded_data,
+    &ett_atn_ulcs_PDV_list,
+    &ett_atn_ulcs_T_presentation_data_values,
+    &ett_atn_ulcs_EXTERNALt,
+    &ett_atn_ulcs_T_encoding,
+    &ett_atn_ulcs_ACSE_apdu,
+    &ett_atn_ulcs_AARQ_apdu,
+    &ett_atn_ulcs_T_aarq_apdu_protocol_version,
+    &ett_atn_ulcs_AARE_apdu,
+    &ett_atn_ulcs_T_aare_apdu_protocol_version,
+    &ett_atn_ulcs_RLRQ_apdu,
+    &ett_atn_ulcs_RLRE_apdu,
+    &ett_atn_ulcs_ABRT_apdu,
+    &ett_atn_ulcs_ACSE_requirements,
+    &ett_atn_ulcs_Application_context_name_list,
+    &ett_atn_ulcs_AP_title,
+    &ett_atn_ulcs_AE_qualifier,
+    &ett_atn_ulcs_Associate_source_diagnostic,
+    &ett_atn_ulcs_Association_information,
+    &ett_atn_ulcs_Authentication_value,
+    &ett_atn_ulcs_T_other,
+    &ett_atn_ulcs_Name,
+    &ett_atn_ulcs_RDNSequence,
+    &ett_atn_ulcs_RelativeDistinguishedName,
+    &ett_atn_ulcs_AttributeTypeAndValue,
+
+/*--- End of included file: packet-atn-ulcs-ettarr.c ---*/
+#line 860 "../../asn1/atn-ulcs/packet-atn-ulcs-template.c"
+				&ett_atn_ses,
+				&ett_atn_pres,
+				&ett_atn_acse,
+				&ett_atn_ulcs
+    };
+		
+		proto_atn_ulcs = proto_register_protocol (
+				ATN_ULCS_PROTO ,
+				"ATN-ULCS",
+				"atn-ulcs");
+			
+		proto_register_field_array (
+				proto_atn_ulcs,
+				hf_atn_ulcs,
+				array_length(hf_atn_ulcs));
+
+		proto_register_subtree_array (
+				ett,
+				array_length (ett));
+
+		new_register_dissector(
+				"atn-ulcs",
+				dissect_atn_ulcs,
+				proto_atn_ulcs);
+
+		atn_cm_handle = find_dissector("atn-cm");
+		atn_cpdlc_handle = find_dissector("atn-cpdlc");
+		
+		/* initiate sub dissector list */
+		register_heur_dissector_list(
+				"atn-ulcs",
+				&atn_ulcs_heur_subdissector_list);
+
+		/* init aare/aare data */
+		if(!aarq_data_tree) {
+				aarq_data_tree =  se_tree_create(
+						EMEM_TREE_TYPE_RED_BLACK,
+						"aarq-data"); }
+
+		if(!atn_conversation_tree) {
+				atn_conversation_tree =  se_tree_create(
+						EMEM_TREE_TYPE_RED_BLACK,
+						"atn-conversations"); }
+}
+
+void proto_reg_handoff_atn_ulcs(void)
+{
+		/* add session dissector to cotp dissector list dissector list*/
+		heur_dissector_add(
+				"cotp",
+				dissect_atn_ulcs_heur,
+				proto_atn_ulcs);
+}
+
+/*
+ * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 2
+ * tab-width: 2
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vi: set shiftwidth=2 tabstop=2 noexpandtab:
+ * :indentSize=2:tabSize=2:noTabs=false:
+ */