M3UA (MTP3 User Adaptation layer) support, from Michael Tuexen.

svn path=/trunk/; revision=2855

1 files changed, 973 insertions, 0 deletions

diff --git a/packet-m3ua.c b/packet-m3ua.c
new file mode 100644
index 0000000000..f7ba174edf
--- /dev/null
+++ b/packet-m3ua.c
@@ -0,0 +1,973 @@
+/* packet-m3ua.c
+ * Routines for MTP3 User Adaptation Layer dissection
+ * It is hopefully (needs testing) compilant to
+ * http://www.ietf.org/internet-drafts/draft-ietf-sigtran-m3ua-05.txt
+ * To do: - clean up the code
+ *        - provide better handling of length parameters
+ *        - provide good information in summary window
+ *
+ * Copyright 2000, Michael Tüxen <Michael.Tuexen@icn.siemens.de>
+ *
+ * $Id: packet-m3ua.c,v 1.1 2001/01/10 09:25:13 guy Exp $
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@unicom.net>
+ * Copyright 1998 Gerald Combs
+ *
+ * Copied from README.developer
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+
+
+#ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+
+#ifdef HAVE_NETINET_IN_H
+# include <netinet/in.h>
+#endif
+
+#include <string.h>
+#include <glib.h>
+
+#ifdef NEED_SNPRINTF_H
+# include "snprintf.h"
+#endif
+
+#include "packet.h"
+#include "packet-ip.h"
+
+
+#define SCTP_PORT_M3UA 2905
+
+#define VERSION_LENGTH         1
+#define RESERVED_LENGTH        1
+#define MESSAGE_CLASS_LENGTH   1
+#define MESSAGE_TYPE_LENGTH    1
+#define MESSAGE_LENGTH_LENGTH  4
+#define COMMON_HEADER_LENGTH   (VERSION_LENGTH + RESERVED_LENGTH + MESSAGE_CLASS_LENGTH + \
+                                MESSAGE_TYPE_LENGTH + MESSAGE_LENGTH_LENGTH)
+
+#define VERSION_OFFSET         0
+#define RESERVED_OFFSET        (VERSION_OFFSET + VERSION_LENGTH)
+#define MESSAGE_CLASS_OFFSET   (RESERVED_OFFSET + RESERVED_LENGTH)
+#define MESSAGE_TYPE_OFFSET    (MESSAGE_CLASS_OFFSET + MESSAGE_CLASS_LENGTH)
+#define MESSAGE_LENGTH_OFFSET  (MESSAGE_TYPE_OFFSET + MESSAGE_TYPE_LENGTH)
+
+#define PARAMETER_TAG_LENGTH    2
+#define PARAMETER_LENGTH_LENGTH 2
+#define PARAMETER_HEADER_LENGTH (PARAMETER_TAG_LENGTH + PARAMETER_LENGTH_LENGTH)
+
+#define PARAMETER_TAG_OFFSET      0
+#define PARAMETER_LENGTH_OFFSET   (PARAMETER_TAG_OFFSET + PARAMETER_TAG_LENGTH)
+#define PARAMETER_VALUE_OFFSET    (PARAMETER_LENGTH_OFFSET + PARAMETER_LENGTH_LENGTH)
+#define PARAMETER_HEADER_OFFSET   PARAMETER_TAG_OFFSET
+
+#define NETWORK_APPEARANCE_PARAMETER_TAG       1
+#define PROTOCOL_DATA_PARAMETER_TAG            3
+#define INFO_PARAMETER_TAG                     4
+#define AFFECTED_DESTINATIONS_PARAMETER_TAG    5
+#define ROUTING_CONTEXT_PARAMETER_TAG          6
+#define DIAGNOSTIC_INFORMATION_PARAMETER_TAG   7
+#define HEARTBEAT_DATA_PARAMETER_TAG           8
+#define USER_CAUSE_PARAMETER_TAG               9
+#define REASON_PARAMETER_TAG                  10
+#define TRAFFIC_MODE_TYPE_PARAMETER_TAG       11
+#define ERROR_CODE_PARAMETER_TAG              12
+#define STATUS_TYPE_PARAMETER_TAG             13
+#define CONGESTION_INDICATION_PARAMETER_TAG   14
+
+
+static const value_string m3ua_parameter_tag_values[] = {
+  { NETWORK_APPEARANCE_PARAMETER_TAG,           "Network appearance" },
+  { PROTOCOL_DATA_PARAMETER_TAG,                "Protocol data" },
+  { INFO_PARAMETER_TAG,                         "Info" },
+  { AFFECTED_DESTINATIONS_PARAMETER_TAG,        "Affected destinations" },
+  { ROUTING_CONTEXT_PARAMETER_TAG,              "Routing context" },
+  { DIAGNOSTIC_INFORMATION_PARAMETER_TAG,       "Diagnostic information" },
+  { HEARTBEAT_DATA_PARAMETER_TAG,               "Heartbeat data" },
+  { USER_CAUSE_PARAMETER_TAG,                   "User / Cause" },
+  { REASON_PARAMETER_TAG,                       "Reason" },
+  { TRAFFIC_MODE_TYPE_PARAMETER_TAG,            "Traffic mode type" },
+  { ERROR_CODE_PARAMETER_TAG,                   "Error code" },
+  { STATUS_TYPE_PARAMETER_TAG,                  "Status type" }, 
+  { CONGESTION_INDICATION_PARAMETER_TAG,        "Congestion Indication" },
+  { 0,                           NULL } };
+
+#define PROTOCOL_VERSION_RELEASE_1             1
+
+static const value_string m3ua_protocol_version_values[] = {
+  { PROTOCOL_VERSION_RELEASE_1,  "Release 1" },
+  { 0,                           NULL } };
+
+#define MESSAGE_CLASS_MGMT_MESSAGE        0
+#define MESSAGE_CLASS_TFER_MESSAGE        1
+#define MESSAGE_CLASS_SSNM_MESSAGE        2
+#define MESSAGE_CLASS_ASPSM_MESSAGE       3
+#define MESSAGE_CLASS_ASPTM_MESSAGE       4
+
+static const value_string m3ua_message_class_values[] = {
+  { MESSAGE_CLASS_MGMT_MESSAGE,   "Management messages" },
+  { MESSAGE_CLASS_TFER_MESSAGE,   "Transfer messages" },
+  { MESSAGE_CLASS_SSNM_MESSAGE,   "SS7 signalling network management messages" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE,  "ASP state maintenance messages" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE,  "ASP traffic maintenance messages" },
+  { 0,                           NULL } };
+
+#define MESSAGE_TYPE_ERR                  0
+#define MESSAGE_TYPE_NTFY                 1
+
+#define MESSAGE_TYPE_DATA                 1
+
+#define MESSAGE_TYPE_DUNA                 1
+#define MESSAGE_TYPE_DAVA                 2
+#define MESSAGE_TYPE_DAUD                 3
+#define MESSAGE_TYPE_SCON                 4
+#define MESSAGE_TYPE_DUPU                 5
+
+#define MESSAGE_TYPE_UP                   1
+#define MESSAGE_TYPE_DOWN                 2
+#define MESSAGE_TYPE_BEAT                 3
+#define MESSAGE_TYPE_UP_ACK               4
+#define MESSAGE_TYPE_DOWN_ACK             5
+#define MESSAGE_TYPE_BEAT_ACK             6
+
+#define MESSAGE_TYPE_ACTIVE               1
+#define MESSAGE_TYPE_INACTIVE             2
+#define MESSAGE_TYPE_ACTIVE_ACK           3
+#define MESSAGE_TYPE_INACTIVE_ACK         4
+
+static const value_string m3ua_message_class_type_values[] = {
+  { MESSAGE_CLASS_MGMT_MESSAGE  * 256 + MESSAGE_TYPE_ERR,           "Error (ERR)" },
+  { MESSAGE_CLASS_MGMT_MESSAGE  * 256 + MESSAGE_TYPE_NTFY,          "Notify (NTFY)" },
+  { MESSAGE_CLASS_TFER_MESSAGE  * 256 + MESSAGE_TYPE_DATA,          "Payload data (DATA)" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DUNA,          "Destination unavailable (DUNA)" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DAVA,          "Destination available (DAVA)" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DAUD,          "Destination state audit (DAUD)" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_SCON,          "SS7 Network congestion state (SCON)" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DUPU,          "Destination userpart unavailable (DUPU)" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_UP,            "ASP up (UP)" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_DOWN,          "ASP down (DOWN)" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_BEAT,          "Heartbeat (BEAT)" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_UP_ACK,        "ASP up ack (UP ACK)" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_DOWN_ACK,      "ASP down ack (DOWN ACK)" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_BEAT_ACK,      "Heartbeat ack (BEAT ACK)" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_ACTIVE ,       "ASP active (ACTIVE)" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_INACTIVE ,     "ASP inactive (INACTIVE)" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_ACTIVE_ACK ,   "ASP active ack (ACTIVE ACK)" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_INACTIVE_ACK , "ASP inactive ack (INACTIVE ACK)" },
+  { 0,                           NULL } };
+
+static const value_string m3ua_message_class_type_acro_values[] = {
+  { MESSAGE_CLASS_MGMT_MESSAGE  * 256 + MESSAGE_TYPE_ERR,           "ERR" },
+  { MESSAGE_CLASS_MGMT_MESSAGE  * 256 + MESSAGE_TYPE_NTFY,          "NTFY" },
+  { MESSAGE_CLASS_TFER_MESSAGE  * 256 + MESSAGE_TYPE_DATA,          "DATA" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DUNA,          "DUNA" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DAVA,          "DAVA" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DAUD,          "DAUD" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_SCON,          "SCON" },
+  { MESSAGE_CLASS_SSNM_MESSAGE  * 256 + MESSAGE_TYPE_DUPU,          "DUPU" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_UP,            "ASP_UP" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_DOWN,          "ASP_DOWN" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_BEAT,          "BEAT" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_UP_ACK,        "ASP_UP_ACK" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_DOWN_ACK,      "ASP_DOWN_ACK" },
+  { MESSAGE_CLASS_ASPSM_MESSAGE * 256 + MESSAGE_TYPE_BEAT_ACK,      "BEAT_ACK" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_ACTIVE ,       "ASP_ACTIVE" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_INACTIVE ,     "ASP_INACTIVE" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_ACTIVE_ACK ,   "ASP_ACTIVE_ACK" },
+  { MESSAGE_CLASS_ASPTM_MESSAGE * 256 + MESSAGE_TYPE_INACTIVE_ACK , "ASP_INACTIVE_ACK" },
+  { 0,                           NULL } };
+
+
+
+
+#define NETWORK_APPEARANCE_LENGTH 4
+#define NETWORK_APPEARANCE_OFFSET PARAMETER_VALUE_OFFSET
+
+#define PROTOCOL_DATA_OFFSET PARAMETER_VALUE_OFFSET
+
+#define INFO_STRING_OFFSET PARAMETER_VALUE_OFFSET
+
+
+#define INVALID_VERSION_ERROR_CODE               1
+#define INVALID_NETWORK_APPEARANCE_ERROR_CODE    2
+#define UNSUPPORTED_MESSAGE_TYPE_ERROR_CODE      3
+#define INVALID_MESSAGE_TYPE_ERROR_CODE          4
+#define INVALID_TRAFFIC_HANDLING_MODE_ERROR_CODE 5
+#define UNEXPECTED_MESSAGE_ERROR_CODE            6
+#define PROTOCOL_ERROR_ERROR_CODE                7
+#define INVALID_ROUTING_CONTEXT_ERROR_CODE       8
+
+static const value_string m3ua_error_code_values[] = {
+  { INVALID_VERSION_ERROR_CODE,               "Invalid version" },
+  { INVALID_NETWORK_APPEARANCE_ERROR_CODE,    "Invalid network appearance" },
+  { UNSUPPORTED_MESSAGE_TYPE_ERROR_CODE,      "Unsupported message type" },
+  { INVALID_MESSAGE_TYPE_ERROR_CODE,          "Invalid message type" },
+  { INVALID_TRAFFIC_HANDLING_MODE_ERROR_CODE, "Invalid traffic handling mode" },
+  { UNEXPECTED_MESSAGE_ERROR_CODE,            "Unexpected message" },
+  { PROTOCOL_ERROR_ERROR_CODE,                "Protocol error" },
+  { INVALID_ROUTING_CONTEXT_ERROR_CODE,       "Invalid routing contexted" },
+  { 0,                           NULL } };
+
+#define ERROR_CODE_LENGTH 4
+#define ERROR_CODE_OFFSET PARAMETER_VALUE_OFFSET
+
+#define AS_STATE_CHANGE_TYPE       1
+#define OTHER_TYPE                 2
+
+static const value_string m3ua_status_type_values[] = {
+  { AS_STATE_CHANGE_TYPE,            "Application server state change" },
+  { OTHER_TYPE,                      "Other" },
+  { 0,                           NULL } };
+
+#define RESERVED_INFO              1
+#define AS_INACTIVE_INFO           2
+#define AS_ACTIVE_INFO             3
+#define AS_PENDING_INFO            4
+
+#define INSUFFICIENT_ASP_RES_INFO  1
+#define ALTERNATE_ASP_ACTIVE_INFO  2
+
+static const value_string m3ua_status_type_info_values[] = {
+  { AS_STATE_CHANGE_TYPE * 256 * 256 + RESERVED_INFO,             "Reserved" },
+  { AS_STATE_CHANGE_TYPE * 256 * 256 + AS_INACTIVE_INFO,          "Application server inactive" },
+  { AS_STATE_CHANGE_TYPE * 256 * 256 + AS_ACTIVE_INFO,            "Application server active" },
+  { AS_STATE_CHANGE_TYPE * 256 * 256 + AS_PENDING_INFO,           "Application server pending" },
+  { OTHER_TYPE           * 256 * 256 + INSUFFICIENT_ASP_RES_INFO, "Insufficient ASP resources active in AS" },
+  { OTHER_TYPE           * 256 * 256 + ALTERNATE_ASP_ACTIVE_INFO, "Alternate ASP active" },
+  {0,                           NULL } };
+
+#define STATUS_TYPE_LENGTH 2
+#define STATUS_INFO_LENGTH 2
+
+#define STATUS_TYPE_OFFSET PARAMETER_VALUE_OFFSET
+#define STATUS_INFO_OFFSET (STATUS_TYPE_OFFSET + STATUS_TYPE_LENGTH)
+
+#define UNKNOWN_UNAVAIL_CAUSE                  0
+#define UNEQUIPPED_REMOTE_USER_UNAVAIL_CAUSE   1
+#define INACCESSABLE_REMOTE_USER_UNAVAIL_CAUSE 2
+
+static const value_string m3ua_unavailability_cause_values[] = {
+  { UNKNOWN_UNAVAIL_CAUSE,                             "Unknown" },
+  { UNEQUIPPED_REMOTE_USER_UNAVAIL_CAUSE,              "Unequipped remote user" },
+  { INACCESSABLE_REMOTE_USER_UNAVAIL_CAUSE,            "Inaccessable remote user" },
+  {0,                           NULL } };
+
+#define RESERVED_0_USER_ID                0
+#define RESERVED_1_USER_ID                1
+#define RESERVED_2_USER_ID                2
+#define SCCP_USER_ID                      3
+#define TUP_USER_ID                       4
+#define ISUP_USER_ID                      5
+#define RESERVED_6_USER_ID                6
+#define RESERVED_7_USER_ID                7
+#define RESERVED_8_USER_ID                8
+#define BROADBAND_ISUP_USER_ID            9
+#define SATELLITE_ISUP_USER_ID           10
+
+static const value_string m3ua_user_identity_values[] = {
+  { RESERVED_0_USER_ID,                             "Reserved" },
+  { RESERVED_1_USER_ID,                             "Reserved" },
+  { RESERVED_2_USER_ID,                             "Reserved" },
+  { SCCP_USER_ID,                                   "SCCP" },
+  { TUP_USER_ID,                                    "TUP" },
+  { ISUP_USER_ID,                                   "ISUP" },
+  { RESERVED_6_USER_ID,                             "Reserved" },
+  { RESERVED_7_USER_ID,                             "Reserved" },
+  { RESERVED_8_USER_ID,                             "Reserved" },
+  { BROADBAND_ISUP_USER_ID,                         "Broadband ISUP" },
+  { SATELLITE_ISUP_USER_ID,                         "Satellite ISUP" },
+  {0,                           NULL } };
+
+#define CAUSE_LENGTH 2
+#define USER_LENGTH  2
+
+#define CAUSE_OFFSET  PARAMETER_VALUE_OFFSET
+#define USER_OFFSET   (CAUSE_OFFSET + CAUSE_LENGTH)
+
+#define UNSPECIFIED_REASON          0
+#define USER_UNAVAILABLE_REASON     1
+#define MANAGEMENT_BLOCKING_REASON  2
+
+static const value_string m3ua_reason_values[] = {
+  { UNSPECIFIED_REASON,                             "Unspecified" },
+  { USER_UNAVAILABLE_REASON,                        "User unavailable" },
+  { MANAGEMENT_BLOCKING_REASON,                     "Management blocking" },
+  {0,                           NULL } };
+
+#define REASON_LENGTH 4
+#define REASON_OFFSET PARAMETER_VALUE_OFFSET
+
+
+#define OVER_RIDE_TYPE           1
+#define LOAD_SHARE_TYPE          2
+#define OVER_RIDE_STANDBY_TYPE   3
+#define LOAD_SHARE_STANDBY_TYPE  4
+
+static const value_string m3ua_traffic_mode_type_values[] = {
+  { OVER_RIDE_TYPE ,                             "Over-ride" },
+  { LOAD_SHARE_TYPE,                             "Load-share" },
+  { OVER_RIDE_STANDBY_TYPE,                      "Over-ride (standby)" },
+  { LOAD_SHARE_STANDBY_TYPE,                     "Load-share (standby)" },
+  {0,                           NULL } };
+
+#define TRAFFIC_MODE_TYPE_LENGTH 4
+#define TRAFFIC_MODE_TYPE_OFFSET PARAMETER_VALUE_OFFSET
+
+#define ROUTING_CONTEXT_LENGTH 4
+
+#define AFFECTED_DESTINATION_LENGTH 4
+#define AFFECTED_MASK_LENGTH        1
+#define AFFECTED_DPC_LENGTH         3
+
+#define AFFECTED_MASK_OFFSET        0
+#define AFFECTED_DPC_OFFSET         (AFFECTED_MASK_OFFSET + AFFECTED_MASK_LENGTH)
+
+#define NO_CONGESTION_LEVEL         0
+#define CONGESTION_LEVEL_1_LEVEL    1
+#define CONGESTION_LEVEL_2_LEVEL    2
+#define CONGESTION_LEVEL_3_LEVEL    3
+
+static const value_string m3ua_congestion_level_values[] = {
+  { NO_CONGESTION_LEVEL,                             "No congestion or undefined" },
+  { CONGESTION_LEVEL_1_LEVEL,                        "Congestion level 1" },
+  { CONGESTION_LEVEL_2_LEVEL,                        "Congestion level 2" },
+  { CONGESTION_LEVEL_3_LEVEL,                        "Congestion level 3" },
+  {0,                           NULL } };
+
+#define CONG_IND_RESERVED_LENGTH    3
+#define CONG_IND_LEVEL_LENGTH       1
+
+#define CONG_IND_RESERVED_OFFSET     PARAMETER_VALUE_OFFSET
+#define CONG_IND_LEVEL_OFFSET        (CONG_IND_RESERVED_OFFSET + CONG_IND_RESERVED_LENGTH)
+
+/* Initialize the protocol and registered fields */
+static int proto_m3ua = -1;
+static int hf_m3ua_version = -1;
+static int hf_m3ua_reserved = -1;
+static int hf_m3ua_message_class = -1;
+static int hf_m3ua_message_type = -1;
+static int hf_m3ua_message_length = -1;
+static int hf_m3ua_parameter_tag = -1;
+static int hf_m3ua_parameter_length = -1;
+static int hf_m3ua_network_appearance = -1;
+static int hf_m3ua_info_string = -1;
+static int hf_m3ua_error_code = -1;
+static int hf_m3ua_status_type = -1;
+static int hf_m3ua_status_info = -1;
+static int hf_m3ua_unavailability_cause = -1;
+static int hf_m3ua_user_identity = -1;
+static int hf_m3ua_reason = -1;
+static int hf_m3ua_traffic_mode_type = -1;
+static int hf_m3ua_routing_context = -1;
+static int hf_m3ua_mask = -1;
+static int hf_m3ua_dpc = -1;
+static int hf_m3ua_congestion_level = -1;
+
+/* Initialize the subtree pointers */
+static gint ett_m3ua = -1;
+static gint ett_m3ua_parameter = -1;
+static gint ett_m3ua_affected_destination = -1;
+
+static guint 
+nr_of_padding_bytes (guint length)
+{
+  guint remainder;
+
+  remainder = length % 4;
+
+  if (remainder == 0)
+    return 0;
+  else
+    return 4 - remainder;
+}
+
+static void
+dissect_m3ua_common_header(tvbuff_t *common_header_tvb, packet_info *pinfo, proto_tree *m3ua_tree)
+{
+  guint8  version, reserved, message_class, message_type;
+  guint32 message_length;
+
+  /* Extract the common header */
+  version        = tvb_get_guint8(common_header_tvb, VERSION_OFFSET);
+  reserved       = tvb_get_guint8(common_header_tvb, RESERVED_OFFSET);
+  message_class  = tvb_get_guint8(common_header_tvb, MESSAGE_CLASS_OFFSET);
+  message_type   = tvb_get_guint8(common_header_tvb, MESSAGE_TYPE_OFFSET);
+  message_length = tvb_get_ntohl (common_header_tvb, MESSAGE_LENGTH_OFFSET);
+
+  if (check_col(pinfo->fd, COL_INFO)) {
+    col_append_str(pinfo->fd, COL_INFO, val_to_str(message_class * 256 + message_type, m3ua_message_class_type_acro_values, "reserved"));
+    col_append_str(pinfo->fd, COL_INFO, " ");
+  };
+
+  /* add the components of the common header to the protocol tree */
+  proto_tree_add_uint_format(m3ua_tree, hf_m3ua_version, 
+			     common_header_tvb, VERSION_OFFSET, VERSION_LENGTH,
+			     version, "Version: %u (%s)",
+			     version, val_to_str(version, m3ua_protocol_version_values, "unknown"));
+  proto_tree_add_uint(m3ua_tree, hf_m3ua_reserved,
+		      common_header_tvb, RESERVED_OFFSET, RESERVED_LENGTH,
+		      reserved);
+  proto_tree_add_uint_format(m3ua_tree, hf_m3ua_message_class, 
+			     common_header_tvb, MESSAGE_CLASS_OFFSET, MESSAGE_CLASS_LENGTH,
+			     message_class, "Message class: %u (%s)",
+			     message_class, val_to_str(message_class, m3ua_message_class_values, "reserved"));
+  proto_tree_add_uint_format(m3ua_tree, hf_m3ua_message_type, 
+			     common_header_tvb, MESSAGE_TYPE_OFFSET, MESSAGE_TYPE_LENGTH,
+			     message_type, "Message type: %u (%s)",
+			     message_type, val_to_str(message_class * 256 + message_type, m3ua_message_class_type_values, "reserved"));
+  proto_tree_add_uint(m3ua_tree, hf_m3ua_message_length,
+		      common_header_tvb, MESSAGE_LENGTH_OFFSET, MESSAGE_LENGTH_LENGTH,
+		      message_length);
+}
+static void
+dissect_m3ua_network_appearance_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint32 network_appearance;
+
+  network_appearance = tvb_get_ntohl(parameter_tvb, NETWORK_APPEARANCE_OFFSET);
+  
+  proto_tree_add_uint(parameter_tree, hf_m3ua_network_appearance, 
+		      parameter_tvb, NETWORK_APPEARANCE_OFFSET, NETWORK_APPEARANCE_LENGTH,
+		      network_appearance);
+ 
+  proto_item_set_text(parameter_item, "Network appearance: %u", network_appearance);
+}
+
+static void
+dissect_m3ua_protocol_data_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 length, protocol_data_length;
+  
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  
+  protocol_data_length = length - PARAMETER_HEADER_LENGTH;
+
+  proto_tree_add_text(parameter_tree, parameter_tvb, PROTOCOL_DATA_OFFSET, protocol_data_length,
+		      "Protocol data (%u byte%s)",
+		      protocol_data_length, plurality(protocol_data_length, "", "s"));
+
+  proto_item_set_text(parameter_item, "Protocol data (SS7 message of %u byte%s)",
+		      protocol_data_length, plurality(protocol_data_length, "", "s"));
+}
+
+static void
+dissect_m3ua_info_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 length, info_string_length;
+  char *info_string;
+
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  
+  info_string_length = length - PARAMETER_HEADER_LENGTH;
+  info_string = (char *)tvb_get_ptr(parameter_tvb, INFO_STRING_OFFSET, info_string_length);
+
+  proto_tree_add_string(parameter_tree, hf_m3ua_info_string,
+			parameter_tvb, INFO_STRING_OFFSET, info_string_length ,
+			info_string);
+
+  proto_item_set_text(parameter_item, "Info String (%s)", info_string);
+}
+
+static void
+dissect_m3ua_affected_destinations_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint8  mask;
+  guint16 length, number_of_destinations, destination_number;
+  guint32 dpc;
+  gint destination_offset;
+  proto_item *destination_item;
+  proto_tree *destination_tree;
+
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  number_of_destinations= (length - PARAMETER_HEADER_LENGTH) / 4;
+
+  destination_offset = PARAMETER_VALUE_OFFSET;
+  for(destination_number=1; destination_number <= number_of_destinations; destination_number++) {
+    mask = tvb_get_guint8(parameter_tvb, destination_offset + AFFECTED_MASK_OFFSET);
+    dpc  = tvb_get_ntoh24(parameter_tvb, destination_offset + AFFECTED_DPC_OFFSET);
+    destination_item = proto_tree_add_text(parameter_tree, parameter_tvb, destination_offset, AFFECTED_DESTINATION_LENGTH,
+					  "Affected destination");
+    destination_tree = proto_item_add_subtree(destination_item, ett_m3ua_affected_destination);
+
+    proto_tree_add_uint(destination_tree, hf_m3ua_mask, 
+			parameter_tvb, destination_offset + AFFECTED_MASK_OFFSET, AFFECTED_MASK_LENGTH,
+			mask);
+    proto_tree_add_uint(destination_tree, hf_m3ua_dpc, 
+			parameter_tvb, destination_offset + AFFECTED_DPC_OFFSET, AFFECTED_DPC_LENGTH,
+			dpc);
+    destination_offset += AFFECTED_DESTINATION_LENGTH;
+  };
+  proto_item_set_text(parameter_item, "Affected destinations parameter (%u destination%s)",
+		      number_of_destinations, plurality(number_of_destinations, "", "s"));
+
+}
+
+static void
+dissect_m3ua_routing_context_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 length, number_of_contexts, context_number;
+  guint32 context;
+  gint context_offset;
+
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  number_of_contexts = (length - PARAMETER_HEADER_LENGTH) / 4;
+
+  context_offset = PARAMETER_VALUE_OFFSET;
+  for(context_number=1; context_number <= number_of_contexts; context_number++) {
+    context = tvb_get_ntohl(parameter_tvb, context_offset);
+    proto_tree_add_uint(parameter_tree, hf_m3ua_routing_context, 
+			parameter_tvb, context_offset, ROUTING_CONTEXT_LENGTH,
+			context);
+    context_offset += ROUTING_CONTEXT_LENGTH;
+  };
+  proto_item_set_text(parameter_item, "Routing context parameter (%u context%s)",
+		      number_of_contexts, plurality(number_of_contexts, "", "s"));
+}
+
+static void
+dissect_m3ua_diagnostic_information_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 length, diagnostic_info_length;
+  
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  
+  diagnostic_info_length = length - PARAMETER_HEADER_LENGTH;
+
+  proto_tree_add_text(parameter_tree, parameter_tvb, PARAMETER_VALUE_OFFSET, diagnostic_info_length,
+		      "Diagnostic information (%u byte%s)",
+		      diagnostic_info_length, plurality(diagnostic_info_length, "", "s"));
+
+  proto_item_set_text(parameter_item, "Diagnostic information (%u byte%s)",
+		      diagnostic_info_length, plurality(diagnostic_info_length, "", "s"));
+}
+
+static void
+dissect_m3ua_heartbeat_data_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 length, heartbeat_data_length;
+  
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  
+  heartbeat_data_length = length - PARAMETER_HEADER_LENGTH;
+
+  proto_tree_add_text(parameter_tree, parameter_tvb, PARAMETER_VALUE_OFFSET, heartbeat_data_length,
+		      "Heartbeat data (%u byte%s)",
+		      heartbeat_data_length, plurality(heartbeat_data_length, "", "s"));
+
+  proto_item_set_text(parameter_item, "Heartbeat data (%u byte%s)",
+		      heartbeat_data_length, plurality(heartbeat_data_length, "", "s"));
+}
+
+static void
+dissect_m3ua_user_cause_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 cause, user;
+
+  cause = tvb_get_ntohs(parameter_tvb, CAUSE_OFFSET);
+  user  = tvb_get_ntohs(parameter_tvb, USER_OFFSET);
+
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_unavailability_cause, 
+			     parameter_tvb, CAUSE_OFFSET, CAUSE_LENGTH,
+			     cause, "Unavailability cause: %u (%s)",
+			     cause, val_to_str(cause, m3ua_unavailability_cause_values, "unknown"));
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_user_identity, 
+			     parameter_tvb, USER_OFFSET, USER_LENGTH,
+			     user, "User identity: %u (%s)",
+			     user, val_to_str(user, m3ua_user_identity_values, "unknown"));
+  proto_item_set_text(parameter_item, "User / Cause parameter (%s: %s)",
+		      val_to_str(user, m3ua_user_identity_values, "Unknown user"),
+		      val_to_str(cause, m3ua_unavailability_cause_values, "unknown cause"));
+}
+
+static void
+dissect_m3ua_reason_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint32 reason;
+
+  reason = tvb_get_ntohl(parameter_tvb, REASON_OFFSET);
+
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_reason, 
+			     parameter_tvb, REASON_OFFSET, REASON_LENGTH,
+			     reason, "Reason: %u (%s)",
+			     reason, val_to_str(reason, m3ua_reason_values, "unknown"));
+  proto_item_set_text(parameter_item, "Reason parameter (%s)",
+		      val_to_str(reason, m3ua_reason_values, "unknown"));
+}
+
+static void
+dissect_m3ua_traffic_mode_type_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint32 traffic_mode_type;
+
+  traffic_mode_type = tvb_get_ntohl(parameter_tvb, TRAFFIC_MODE_TYPE_OFFSET);
+
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_traffic_mode_type, 
+			     parameter_tvb, TRAFFIC_MODE_TYPE_OFFSET, TRAFFIC_MODE_TYPE_LENGTH,
+			     traffic_mode_type, "Traffic mode type: %u (%s)",
+			     traffic_mode_type, val_to_str(traffic_mode_type, m3ua_traffic_mode_type_values, "unknown"));
+  proto_item_set_text(parameter_item, "Traffic mode type parameter (%s)",
+		      val_to_str(traffic_mode_type, m3ua_traffic_mode_type_values, "unknown"));
+}
+
+static void
+dissect_m3ua_error_code_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint32 error_code;
+
+  error_code = tvb_get_ntohl(parameter_tvb, ERROR_CODE_OFFSET);
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_error_code, 
+			     parameter_tvb, ERROR_CODE_OFFSET, ERROR_CODE_LENGTH,
+			     error_code, "Error code: %u (%s)",
+			     error_code, val_to_str(error_code, m3ua_error_code_values, "unknown"));
+  proto_item_set_text(parameter_item, "Error code parameter (%s)",
+		      val_to_str(error_code, m3ua_error_code_values, "unknown"));
+}
+
+static void
+dissect_m3ua_status_type_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 status_type, status_info;
+
+  status_type = tvb_get_ntohs(parameter_tvb, STATUS_TYPE_OFFSET);
+  status_info = tvb_get_ntohs(parameter_tvb, STATUS_INFO_OFFSET);
+
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_status_type, 
+			     parameter_tvb, STATUS_TYPE_OFFSET, STATUS_TYPE_LENGTH,
+			     status_type, "Status type: %u (%s)",
+			     status_type, val_to_str(status_type, m3ua_status_type_values, "unknown"));
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_status_info, 
+			     parameter_tvb, STATUS_INFO_OFFSET, STATUS_INFO_LENGTH,
+			     status_info, "Status info: %u (%s)",
+			     status_info, val_to_str(status_type * 256 * 256 + 
+                                                     status_info, m3ua_status_type_info_values, "unknown"));
+
+  proto_item_set_text(parameter_item, "Status type / ID (%s)",
+		      val_to_str(status_type * 256 * 256 + 
+				 status_info, m3ua_status_type_info_values, "unknown status information"));
+}
+
+static void
+dissect_m3ua_congestion_indication_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint8 level;
+  
+  level = tvb_get_guint8(parameter_tvb, CONG_IND_LEVEL_OFFSET);
+
+  proto_tree_add_text(parameter_tree, parameter_tvb, CONG_IND_RESERVED_OFFSET, CONG_IND_RESERVED_LENGTH,
+			"Reserved: %u byte%s",
+			CONG_IND_RESERVED_LENGTH, plurality(CONG_IND_RESERVED_LENGTH, "", "s"));
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_congestion_level, 
+			     parameter_tvb, CONG_IND_LEVEL_OFFSET, CONG_IND_LEVEL_LENGTH,
+			     level, "Congestion level: %u (%s)",
+			     level, val_to_str(level, m3ua_congestion_level_values, "unknown"));
+  proto_item_set_text(parameter_item, "Congestion indication (%s)",
+		      val_to_str(level, m3ua_congestion_level_values, "unknown"));
+}
+
+static void
+dissect_m3ua_unknown_parameter(tvbuff_t *parameter_tvb, proto_tree *parameter_tree, proto_item *parameter_item)
+{
+  guint16 tag, length, parameter_value_length;
+  
+  tag    = tvb_get_ntohs(parameter_tvb, PARAMETER_TAG_OFFSET);
+  length = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+  
+  parameter_value_length = length - PARAMETER_HEADER_LENGTH;
+
+  proto_tree_add_text(parameter_tree, parameter_tvb, PARAMETER_VALUE_OFFSET, parameter_value_length,
+		      "Parameter value (%u byte%s)",
+		      parameter_value_length, plurality(parameter_value_length, "", "s"));
+
+  proto_item_set_text(parameter_item, "Parameter with tag %u and %u byte%s value",
+		      tag, parameter_value_length, plurality(parameter_value_length, "", "s"));
+}
+
+static void
+dissect_m3ua_parameter(tvbuff_t *parameter_tvb, proto_tree *m3ua_tree)
+{
+  guint16 tag, length, padding_length, total_length;
+  proto_item *parameter_item;
+  proto_tree *parameter_tree;
+
+  /* extract tag and length from the parameter */
+  tag            = tvb_get_ntohs(parameter_tvb, PARAMETER_TAG_OFFSET);
+  length         = tvb_get_ntohs(parameter_tvb, PARAMETER_LENGTH_OFFSET);
+
+  /* calculate padding and total length */
+  padding_length = nr_of_padding_bytes(length);
+  total_length   = length + padding_length;
+
+  /* create proto_tree stuff */
+  parameter_item   = proto_tree_add_text(m3ua_tree, parameter_tvb,
+				     PARAMETER_HEADER_OFFSET, total_length, "Incomplete parameter");
+  parameter_tree   = proto_item_add_subtree(parameter_item, ett_m3ua_parameter);
+
+  /* add tag and length to the m3ua tree */
+  proto_tree_add_uint_format(parameter_tree, hf_m3ua_parameter_tag, 
+			     parameter_tvb, PARAMETER_TAG_OFFSET, PARAMETER_TAG_LENGTH,
+			     tag, "Identifier: %u (%s)",
+			     tag, val_to_str(tag, m3ua_parameter_tag_values, "unknown"));
+  proto_tree_add_uint(parameter_tree, hf_m3ua_parameter_length, 
+		      parameter_tvb, PARAMETER_LENGTH_OFFSET, PARAMETER_LENGTH_LENGTH,
+		      length);
+
+  switch(tag) {
+  case NETWORK_APPEARANCE_PARAMETER_TAG:
+    dissect_m3ua_network_appearance_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case PROTOCOL_DATA_PARAMETER_TAG:
+    dissect_m3ua_protocol_data_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case INFO_PARAMETER_TAG:
+    dissect_m3ua_info_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case AFFECTED_DESTINATIONS_PARAMETER_TAG:
+    dissect_m3ua_affected_destinations_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case ROUTING_CONTEXT_PARAMETER_TAG:
+    dissect_m3ua_routing_context_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case DIAGNOSTIC_INFORMATION_PARAMETER_TAG:
+    dissect_m3ua_diagnostic_information_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case HEARTBEAT_DATA_PARAMETER_TAG:
+    dissect_m3ua_heartbeat_data_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case USER_CAUSE_PARAMETER_TAG:
+    dissect_m3ua_user_cause_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case REASON_PARAMETER_TAG:
+    dissect_m3ua_reason_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case TRAFFIC_MODE_TYPE_PARAMETER_TAG:
+    dissect_m3ua_traffic_mode_type_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case ERROR_CODE_PARAMETER_TAG:
+    dissect_m3ua_error_code_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case  STATUS_TYPE_PARAMETER_TAG:
+    dissect_m3ua_status_type_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  case  CONGESTION_INDICATION_PARAMETER_TAG:
+    dissect_m3ua_congestion_indication_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  default:
+    dissect_m3ua_unknown_parameter(parameter_tvb, parameter_tree, parameter_item);
+    break;
+  };
+
+  if (padding_length > 0)
+    proto_tree_add_text(parameter_tree, parameter_tvb, PARAMETER_HEADER_OFFSET + length, padding_length,
+			"Padding: %u byte%s",
+			padding_length, plurality(padding_length, "", "s"));
+}
+
+static void
+dissect_m3ua_message(tvbuff_t *message_tvb, packet_info *pinfo, proto_tree *m3ua_tree)
+{
+  gint offset, length, padding_length, total_length;
+  tvbuff_t *common_header_tvb, *parameter_tvb;
+
+  offset = 0;
+
+  /* extract and process the common header */
+  common_header_tvb = tvb_new_subset(message_tvb, offset, COMMON_HEADER_LENGTH, COMMON_HEADER_LENGTH);
+  dissect_m3ua_common_header(common_header_tvb, pinfo, m3ua_tree);
+  offset += COMMON_HEADER_LENGTH;
+
+  /* extract zero or more parameters and process them individually */
+  while(tvb_length_remaining(message_tvb, offset)) {
+    length         = tvb_get_ntohs(message_tvb, offset + PARAMETER_LENGTH_OFFSET);
+    padding_length = nr_of_padding_bytes(length);
+    total_length   = length + padding_length;
+    /* create a tvb for the parameter including the padding bytes */
+    parameter_tvb    = tvb_new_subset(message_tvb, offset, total_length, total_length);
+    dissect_m3ua_parameter(parameter_tvb, m3ua_tree); 
+    /* get rid of the handled parameter */
+    offset += total_length;
+  }
+}
+
+static void
+dissect_m3ua(tvbuff_t *message_tvb, packet_info *pinfo, proto_tree *tree)
+{
+  proto_item *ti;
+  proto_tree *m3ua_tree;
+
+  CHECK_DISPLAY_AS_DATA(proto_m3ua, message_tvb, pinfo, tree);
+
+  pinfo->current_proto = "M3UA";
+
+  /* make entry in the Protocol column on summary display */
+  if (check_col(pinfo->fd, COL_PROTOCOL)) 
+    col_set_str(pinfo->fd, COL_PROTOCOL, "M3UA");
+  
+  /* clear the Info column so that if we throw an exception it doesn't
+     show stuff from the protocol above us */
+  if (check_col(pinfo->fd, COL_INFO)) 
+    col_clear(pinfo->fd, COL_INFO);
+
+  /* In the interest of speed, if "tree" is NULL, don't do any work not
+     necessary to generate protocol tree items. */
+  if (tree) {
+    /* create the m3ua protocol tree */
+    ti = proto_tree_add_protocol_format(tree, proto_m3ua, message_tvb, 0, tvb_length(message_tvb), 
+					"MTP 3 User Adaptation Layer");
+    m3ua_tree = proto_item_add_subtree(ti, ett_m3ua);
+    /* dissect the message */
+    dissect_m3ua_message(message_tvb, pinfo, m3ua_tree);
+  };
+}
+
+/* Register the protocol with Ethereal */
+void
+proto_register_m3ua(void)
+{                 
+
+  /* Setup list of header fields */
+  static hf_register_info hf[] = {
+    { &hf_m3ua_version,
+      { "Version", "m3ua.version",
+	FT_UINT8, BASE_DEC, NULL, 0x0,          
+	""}
+    },
+    { &hf_m3ua_reserved,
+      { "Reserved", "m3ua.reserved",
+	FT_UINT8, BASE_HEX, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_message_class,
+      { "Message class", "m3ua.message_class",
+	FT_UINT8, BASE_DEC, NULL, 0x0,          
+	""}
+    },
+    { &hf_m3ua_message_type,
+      { "Message Type", "m3ua.message_type",
+	FT_UINT8, BASE_DEC, NULL, 0x0,          
+	""}
+    },
+    { &hf_m3ua_message_length,
+      { "Message length", "m3ua.message_length",
+	FT_UINT32, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_parameter_tag,
+      { "Parameter Tag", "m3ua.parameter_tag",
+	FT_UINT16, BASE_DEC, NULL, 0x0,          
+	""}
+    },
+    { &hf_m3ua_parameter_length,
+      { "Parameter length", "m3ua.parameter_length",
+	FT_UINT16, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_network_appearance,
+      { "Network appearance", "m3ua.network_appearance",
+	FT_UINT32, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_info_string,
+      { "Info string", "m3ua.info_string",
+	FT_STRING, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_error_code,
+      { "Error code", "m3ua.error_code",
+	FT_UINT32, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_status_type,
+      { "Status type", "m3ua.status_type",
+	FT_UINT16, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_status_info,
+      { "Status info", "m3ua.status_info",
+	FT_UINT16, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_unavailability_cause,
+      { "Unavailability cause", "m3ua.unavailability_cause",
+	FT_UINT16, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_user_identity,
+      { "User Identity", "m3ua.user_identity",
+	FT_UINT16, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_reason,
+      { "Reason", "m3ua.reason",
+	FT_UINT32, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_traffic_mode_type,
+      { "Traffic mode Type", "m3ua.traffic_mode_type",
+	FT_UINT32, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_routing_context,
+      { "Routing context", "m3ua.routing_context",
+	FT_UINT32, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_mask,
+      { "Mask", "m3ua.mask",
+	FT_UINT8, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_dpc,
+      { "Affected DPC", "m3ua.affected_dpc",
+	FT_UINT24, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+    { &hf_m3ua_congestion_level,
+      { "Congestion level", "m3ua.congestion_level",
+	FT_UINT8, BASE_DEC, NULL, 0x0,          
+	""}
+    }, 
+  };
+  
+  /* Setup protocol subtree array */
+  static gint *ett[] = {
+    &ett_m3ua,
+    &ett_m3ua_parameter,
+    &ett_m3ua_affected_destination,
+  };
+  
+  /* Register the protocol name and description */
+  proto_m3ua = proto_register_protocol("MTP 3 User Adaptation Layer",
+                                      "M3UA",  "m3ua");
+  
+  /* Required function calls to register the header fields and subtrees used */
+  proto_register_field_array(proto_m3ua, hf, array_length(hf));
+  proto_register_subtree_array(ett, array_length(ett));
+};
+
+void
+proto_reg_handoff_m3ua(void)
+{
+  dissector_add("sctp.port", SCTP_PORT_M3UA, dissect_m3ua, proto_m3ua);
+}