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packet-gtp.c

/* packet-gtp.c
 *
 * Routines for GTP dissection
 * Copyright 2001, Michal Melerowicz <michal.melerowicz@nokia.com>
 *                 Nicolas Balkota <balkota@mac.com>
 *
 * Updates and corrections:
 * Copyright 2006, Anders Broman <anders.broman@ericsson.com>
 *
 * $Id: packet-gtp.c 19382 2006-09-30 13:40:36Z ulfl $
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 * Ref: 3GPP TS 29.060 version 6.8.0 Release 6
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <glib.h>

#include <epan/packet.h>
#include <epan/prefs.h>
#include <epan/sminmpec.h>
#include "packet-ipv6.h"
#include "packet-ppp.h"
#include "packet-radius.h"
#include "packet-bssap.h"
#include "packet-gsm_a.h"
#include "packet-gsm_map.h"
#include "packet-per.h"
#include "packet-ranap.h"
#include "packet-bssgp.h"

static dissector_table_t ppp_subdissector_table;

#define GTPv0_PORT 3386
#define GTPv1C_PORT 2123                  /* 3G Control PDU */
#define GTPv1U_PORT 2152                  /* 3G T-PDU */

#define GTPv0_HDR_LENGTH 20
#define GTPv1_HDR_LENGTH 12
#define GTP_PRIME_HDR_LENGTH 6

/* to check compliance with ETSI  */
#define GTP_MANDATORY   1
#define GTP_OPTIONAL    2
#define GTP_CONDITIONAL 4

static guint g_gtpv0_port     = GTPv0_PORT;
static guint g_gtpv1c_port    = GTPv1C_PORT;
static guint g_gtpv1u_port    = GTPv1U_PORT;

void proto_reg_handoff_gtp(void);

static int proto_gtp          = -1;

static int hf_gtp_apn                     = -1;
static int hf_gtp_cause                   = -1;
static int hf_gtp_chrg_char               = -1;
static int hf_gtp_chrg_char_s       = -1;
static int hf_gtp_chrg_char_n       = -1;
static int hf_gtp_chrg_char_p       = -1;
static int hf_gtp_chrg_char_f       = -1;
static int hf_gtp_chrg_char_h       = -1;
static int hf_gtp_chrg_char_r       = -1;
static int hf_gtp_chrg_id                 = -1;
static int hf_gtp_chrg_ipv4               = -1;
static int hf_gtp_chrg_ipv6               = -1;
static int hf_gtp_ext_flow_label    = -1;
static int hf_gtp_ext_id                  = -1;
static int hf_gtp_ext_val                 = -1;
static int hf_gtp_flags                   = -1;
static int hf_gtp_flags_ver               = -1;
static int hf_gtp_flags_pt                = -1;
static int hf_gtp_flags_spare1            = -1;
static int hf_gtp_flags_snn               = -1;
static int hf_gtp_flags_spare2            = -1;
static int hf_gtp_flags_e                 = -1;
static int hf_gtp_flags_s                 = -1;
static int hf_gtp_flags_pn                = -1;
static int hf_gtp_flow_ii                 = -1;
static int hf_gtp_flow_label        = -1;
static int hf_gtp_flow_sig                = -1;
static int hf_gtp_gsn_addr_len            = -1;
static int hf_gtp_gsn_addr_type           = -1;
static int hf_gtp_gsn_ipv4                = -1;
static int hf_gtp_gsn_ipv6                = -1;
static int hf_gtp_imsi                    = -1;
static int hf_gtp_length                  = -1;
static int hf_gtp_map_cause               = -1;
static int hf_gtp_message_type            = -1;
static int hf_gtp_ms_reason               = -1;
static int hf_gtp_ms_valid                = -1;
static int hf_gtp_msisdn                  = -1;
static int hf_gtp_next                    = -1;
static int hf_gtp_npdu_number       = -1;
static int hf_gtp_node_ipv4               = -1;
static int hf_gtp_node_ipv6               = -1;
static int hf_gtp_nsapi                   = -1;
static int hf_gtp_ptmsi                   = -1;
static int hf_gtp_ptmsi_sig               = -1;
static int hf_gtp_qos_version       = -1;
static int hf_gtp_qos_spare1        = -1;
static int hf_gtp_qos_delay               = -1;
static int hf_gtp_qos_mean                = -1;
static int hf_gtp_qos_peak                = -1;
static int hf_gtp_qos_spare2        = -1;
static int hf_gtp_qos_precedence    = -1;
static int hf_gtp_qos_spare3        = -1;
static int hf_gtp_qos_reliability   = -1;
static int hf_gtp_qos_al_ret_priority     = -1;
static int hf_gtp_qos_traf_class    = -1;
static int hf_gtp_qos_del_order           = -1;
static int hf_gtp_qos_del_err_sdu   = -1;
static int hf_gtp_qos_max_sdu_size  = -1;
static int hf_gtp_qos_max_ul        = -1;
static int hf_gtp_qos_max_dl        = -1;
static int hf_gtp_qos_res_ber       = -1;
static int hf_gtp_qos_sdu_err_ratio = -1;
static int hf_gtp_qos_trans_delay   = -1;
static int hf_gtp_qos_traf_handl_prio     = -1;
static int hf_gtp_qos_guar_ul       = -1;
static int hf_gtp_qos_guar_dl       = -1;
static int hf_gtp_pkt_flow_id       = -1;
static int hf_gtp_rab_gtpu_dn       = -1;
static int hf_gtp_rab_gtpu_up       = -1;
static int hf_gtp_rab_pdu_dn        = -1;
static int hf_gtp_rab_pdu_up        = -1;
static int hf_gtp_rai_mcc                 = -1;
static int hf_gtp_rai_mnc                 = -1;
static int hf_gtp_rai_rac                 = -1;
static int hf_gtp_rai_lac                 = -1;
static int hf_gtp_ranap_cause       = -1;
static int hf_gtp_recovery                = -1;
static int hf_gtp_reorder                 = -1;
static int hf_gtp_rnc_ipv4                = -1;
static int hf_gtp_rnc_ipv6                = -1;
static int hf_gtp_rp                      = -1;
static int hf_gtp_rp_nsapi                = -1;
static int hf_gtp_rp_sms                  = -1;
static int hf_gtp_rp_spare                = -1;
static int hf_gtp_sel_mode                = -1;
static int hf_gtp_seq_number        = -1;
static int hf_gtp_sndcp_number            = -1;
static int hf_gtp_tear_ind                = -1;
static int hf_gtp_teid                    = -1;
static int hf_gtp_teid_cp                 = -1;
static int hf_gtp_teid_data               = -1;
static int hf_gtp_teid_ii                 = -1;
static int hf_gtp_tft_code                = -1;
static int hf_gtp_tft_spare               = -1;
static int hf_gtp_tft_number        = -1;
static int hf_gtp_tft_eval                = -1;
static int hf_gtp_tid                     = -1;
static int hf_gtp_tlli                    = -1;
static int hf_gtp_tr_comm                 = -1;
static int hf_gtp_trace_ref               = -1;
static int hf_gtp_trace_type        = -1;
static int hf_gtp_unknown                 = -1;
static int hf_gtp_user_addr_pdp_org = -1;
static int hf_gtp_user_addr_pdp_type      = -1;
static int hf_gtp_user_ipv4               = -1;
static int hf_gtp_user_ipv6               = -1;
static int hf_gtp_security_mode           = -1;
static int hf_gtp_no_of_vectors           = -1;
static int hf_gtp_cipher_algorithm  = -1;
static int hf_gtp_cksn_ksi                = -1;
static int hf_gtp_cksn                    = -1;
static int hf_gtp_ksi                     = -1;
static int hf_gtp_ext_length        = -1;
static int hf_gtp_ext_apn_res       = -1;
static int hf_gtp_ext_rat_type            = -1;
static int hf_gtp_ext_geo_loc_type  = -1;
static int hf_gtp_ext_sac                 = -1;
static int hf_gtp_ext_imeisv        = -1;
static int hf_gtp_targetid                = -1;
static int hf_gtp_bssgp_cause       = -1;


/* Initialize the subtree pointers */
static gint ett_gtp                             = -1;
static gint ett_gtp_flags                 = -1;
static gint ett_gtp_ext                   = -1;
static gint ett_gtp_rai                   = -1;
static gint ett_gtp_qos                   = -1;
static gint ett_gtp_auth_tri        = -1;
static gint ett_gtp_flow_ii               = -1;
static gint ett_gtp_rab_cntxt       = -1;
static gint ett_gtp_rp                    = -1;
static gint ett_gtp_pkt_flow_id           = -1;
static gint ett_gtp_chrg_char       = -1;
static gint ett_gtp_user                  = -1;
static gint ett_gtp_mm                    = -1;
static gint ett_gtp_trip                  = -1;
static gint ett_gtp_quint                 = -1;
static gint ett_gtp_pdp                   = -1;
static gint ett_gtp_apn                   = -1;
static gint ett_gtp_proto                 = -1;
static gint ett_gtp_gsn_addr        = -1;
static gint ett_gtp_tft                   = -1;
static gint ett_gtp_tft_pf                = -1;
static gint ett_gtp_tft_flags       = -1;
static gint ett_gtp_rab_setup       = -1;
static gint ett_gtp_hdr_list        = -1;
static gint ett_gtp_chrg_addr       = -1;
static gint ett_gtp_node_addr       = -1;
static gint ett_gtp_rel_pack        = -1;
static gint ett_gtp_can_pack        = -1;
static gint ett_gtp_data_resp       = -1;
static gint ett_gtp_priv_ext        = -1;
static gint ett_gtp_net_cap               = -1;
static gint ett_gtp_ext_tree_apn_res      = -1;
static gint ett_gtp_ext_rat_type          = -1;
static gint ett_gtp_ext_imeisv                  = -1;
static gint ett_gtp_ext_ran_tr_cont             = -1;
static gint ett_gtp_ext_pdp_cont_prio           = -1;
static gint ett_gtp_ext_ssgn_no                       = -1;
static gint ett_gtp_ext_rab_setup_inf           = -1;
static gint ett_gtp_ext_common_flgs             = -1;
static gint ett_gtp_ext_usr_loc_inf             = -1;
static gint ett_gtp_ext_ms_time_zone            = -1;
static gint ett_gtp_ext_camel_chg_inf_con = -1;
static gint ett_GTP_EXT_MBMS_UE_CTX             = -1;
static gint ett_gtp_ext_tmgi                    = -1;
static gint ett_gtp_ext_rim_ra                        = -1;
static gint ett_gtp_ext_mbms_prot_conf_opt      = -1;
static gint ett_gtp_ext_mbms_sa                       = -1;
static gint ett_gtp_ext_bms_ses_dur             = -1;
static gint ett_gtp_ext_src_rnc_pdp_ctx_inf     = -1;
static gint ett_gtp_ext_add_trs_inf             = -1;
static gint ett_gtp_ext_hop_count               = -1;
static gint ett_gtp_ext_sel_plmn_id             = -1;
static gint ett_gtp_ext_mbms_ses_id             = -1;
static gint ett_gtp_ext_mbms_2g_3g_ind          = -1;
static gint ett_gtp_ext_enh_nsapi               = -1;
static gint ett_gtp_ext_ad_mbms_trs_inf   = -1;
static gint ett_gtp_ext_mbms_ses_id_rep_no      = -1;
static gint ett_gtp_ext_mbms_time_to_data_tr    = -1;
static gint ett_gtp_ext_ps_ho_req_ctx           = -1;
static gint ett_gtp_ext_bss_cont                = -1;
static gint ett_gtp_ext_cell_id                 = -1;
static gint ett_gtp_ext_pdu_no                        = -1;
static gint ett_gtp_ext_bssgp_cause             = -1;
static gint ett_gtp_ext_ra_prio_lcs             = -1;
static gint ett_gtp_target_id                   = -1;
static gint ett_gtp_utran_cont                        = -1;
      
static gboolean   gtp_tpdu                = TRUE;
static gboolean   gtp_over_tcp            = TRUE;
static gboolean   gtp_etsi_order          = FALSE;
static guint      gtpv0_port        = 0;
static guint      gtpv1c_port       = 0;
static guint      gtpv1u_port       = 0;

/* Definition of flags masks */
#define GTP_VER_MASK 0xE0

static const value_string ver_types[] = {
      { 0, "GTP release 97/98 version" },
      { 1, "GTP release 99 version" },
      { 2, "None" },
      { 3, "None" },
      { 4, "None" },
      { 5, "None" },
      { 6, "None" },
      { 7, "None" },
      { 0, NULL }
};
static const value_string pt_types[] = {
      { 0, "GTP'" },
      { 1, "GTP" },
      { 0, NULL }
};

#define GTP_PT_MASK                 0x10
#define GTP_SPARE1_MASK       0x0E
#define GTP_SPARE2_MASK       0x08
#define GTP_E_MASK                  0x04
#define GTP_S_MASK                  0x02
#define GTP_SNN_MASK          0x01
#define GTP_PN_MASK                 0x01

/* Definition of 3G charging characteristics masks */
#define GTP_MASK_CHRG_CHAR_S  0xF000
#define GTP_MASK_CHRG_CHAR_N  0x0800
#define GTP_MASK_CHRG_CHAR_P  0x0400
#define GTP_MASK_CHRG_CHAR_F  0x0200
#define GTP_MASK_CHRG_CHAR_H  0x0100
#define GTP_MASK_CHRG_CHAR_R  0x00FF

/* Traffic Flow Templates  mask */
#define GTPv1_TFT_CODE_MASK   0xE0
#define GTPv1_TFT_SPARE_MASK  0x10
#define GTPv1_TFT_NUMBER_MASK 0x0F

/* Definition of GSN Address masks */
#define GTP_EXT_GSN_ADDR_TYPE_MASK        0xC0
#define GTP_EXT_GSN_ADDR_LEN_MASK         0x3F

/* Definition of QoS masks */
#define GTP_EXT_QOS_SPARE1_MASK                             0xC0
#define GTP_EXT_QOS_DELAY_MASK                              0x38
#define GTP_EXT_QOS_RELIABILITY_MASK                  0x07
#define GTP_EXT_QOS_PEAK_MASK                         0xF0
#define GTP_EXT_QOS_SPARE2_MASK                             0x08
#define GTP_EXT_QOS_PRECEDENCE_MASK                   0x07
#define GTP_EXT_QOS_SPARE3_MASK                             0xE0
#define GTP_EXT_QOS_MEAN_MASK                         0x1F
#define GTP_EXT_QOS_TRAF_CLASS_MASK                   0xE0
#define GTP_EXT_QOS_DEL_ORDER_MASK                    0x18
#define GTP_EXT_QOS_DEL_ERR_SDU_MASK                  0x07
#define GTP_EXT_QOS_RES_BER_MASK                      0xF0
#define GTP_EXT_QOS_SDU_ERR_RATIO_MASK                0x0F
#define GTP_EXT_QOS_TRANS_DELAY_MASK                  0xFC
#define GTP_EXT_QOS_TRAF_HANDL_PRIORITY_MASK    0x03

/* Definition of Radio Priority's masks */
#define GTPv1_EXT_RP_NSAPI_MASK                 0xF0
#define GTPv1_EXT_RP_SPARE_MASK                 0x08
#define GTPv1_EXT_RP_MASK                       0x07

/* definitions of GTP messages */
#define GTP_MSG_UNKNOWN                   0x00
#define GTP_MSG_ECHO_REQ                  0x01
#define GTP_MSG_ECHO_RESP                 0x02
#define GTP_MSG_VER_NOT_SUPP        0x03
#define GTP_MSG_NODE_ALIVE_REQ            0x04
#define GTP_MSG_NODE_ALIVE_RESP           0x05
#define GTP_MSG_REDIR_REQ                 0x06
#define GTP_MSG_REDIR_RESP                0x07
#define GTP_MSG_CREATE_PDP_REQ            0x10
#define GTP_MSG_CREATE_PDP_RESP           0x11
#define GTP_MSG_UPDATE_PDP_REQ            0x12
#define GTP_MSG_UPDATE_PDP_RESP           0x13
#define GTP_MSG_DELETE_PDP_REQ            0x14
#define GTP_MSG_DELETE_PDP_RESP           0x15
#define GTP_MSG_CREATE_AA_PDP_REQ   0x16  /* 2G */
#define GTP_MSG_CREATE_AA_PDP_RESP  0x17  /* 2G */
#define GTP_MSG_DELETE_AA_PDP_REQ   0x18  /* 2G */
#define GTP_MSG_DELETE_AA_PDP_RESP  0x19  /* 2G */
#define GTP_MSG_ERR_IND                   0x1A
#define GTP_MSG_PDU_NOTIFY_REQ            0x1B
#define GTP_MSG_PDU_NOTIFY_RESP           0x1C
#define GTP_MSG_PDU_NOTIFY_REJ_REQ  0x1D
#define GTP_MSG_PDU_NOTIFY_REJ_RESP 0x1E
#define GTP_MSG_SUPP_EXT_HDR        0x1F
#define GTP_MSG_SEND_ROUT_INFO_REQ  0x20
#define GTP_MSG_SEND_ROUT_INFO_RESP 0x21
#define GTP_MSG_FAIL_REP_REQ        0x22
#define GTP_MSG_FAIL_REP_RESP       0x23
#define GTP_MSG_MS_PRESENT_REQ            0x24
#define GTP_MSG_MS_PRESENT_RESP           0x25
#define GTP_MSG_IDENT_REQ                 0x30
#define GTP_MSG_IDENT_RESP                0x31
#define GTP_MSG_SGSN_CNTXT_REQ            0x32
#define GTP_MSG_SGSN_CNTXT_RESP           0x33
#define GTP_MSG_SGSN_CNTXT_ACK            0x34
#define GTP_MSG_FORW_RELOC_REQ            0x35
#define GTP_MSG_FORW_RELOC_RESP           0x36
#define GTP_MSG_FORW_RELOC_COMP           0x37
#define GTP_MSG_RELOC_CANCEL_REQ    0x38
#define GTP_MSG_RELOC_CANCEL_RESP   0x39
#define GTP_MSG_FORW_SRNS_CNTXT           0x3A
#define GTP_MSG_FORW_RELOC_ACK            0x3B
#define GTP_MSG_FORW_SRNS_CNTXT_ACK 0x3C

#define GTP_MSG_RAN_INFO_RELAY            70
#define GTP_MBMS_NOTIFY_REQ               96
#define GTP_MBMS_NOTIFY_RES               97
#define GTP_MBMS_NOTIFY_REJ_REQ           98
#define GTP_MBMS_NOTIFY_REJ_RES           99
#define GTP_CREATE_MBMS_CNTXT_REQ   100
#define GTP_CREATE_MBMS_CNTXT_RES   101
#define GTP_UPD_MBMS_CNTXT_REQ            102
#define GTP_UPD_MBMS_CNTXT_RES            103
#define GTP_DEL_MBMS_CNTXT_REQ            104
#define GTP_DEL_MBMS_CNTXT_RES            105
#define GTP_MBMS_REG_REQ                  112
#define GTP_MBMS_REG_RES                  113
#define GTP_MBMS_DE_REG_REQ               114
#define GTP_MBMS_DE_REG_RES               115
#define GTP_MBMS_SES_START_REQ            116
#define GTP_MBMS_SES_START_RES            117
#define GTP_MBMS_SES_STOP_REQ       118
#define GTP_MBMS_SES_STOP_RES       119
#define GTP_MSG_DATA_TRANSF_REQ           0xF0
#define GTP_MSG_DATA_TRANSF_RESP    0xF1
#define GTP_MSG_TPDU                      0xFF

static const value_string message_type[] = {
      { GTP_MSG_UNKNOWN,                        "For future use" },
      { GTP_MSG_ECHO_REQ,                       "Echo request" },
      { GTP_MSG_ECHO_RESP,                "Echo response" },
      { GTP_MSG_VER_NOT_SUPP,             "Version not supported" },
      { GTP_MSG_NODE_ALIVE_REQ,           "Node alive request" },
      { GTP_MSG_NODE_ALIVE_RESP,          "Node alive response" },
      { GTP_MSG_REDIR_REQ,                "Redirection request" },
      { GTP_MSG_REDIR_RESP,               "Redirection response" },
      { GTP_MSG_CREATE_PDP_REQ,           "Create PDP context request" },
      { GTP_MSG_CREATE_PDP_RESP,          "Create PDP context response" },
      { GTP_MSG_UPDATE_PDP_REQ,           "Update PDP context request" },
      { GTP_MSG_UPDATE_PDP_RESP,          "Update PDP context response" },
      { GTP_MSG_DELETE_PDP_REQ,           "Delete PDP context request" },
      { GTP_MSG_DELETE_PDP_RESP,          "Delete PDP context response" },
      { GTP_MSG_CREATE_AA_PDP_REQ,  "Create AA PDP Context Request" },
      { GTP_MSG_CREATE_AA_PDP_RESP, "Create AA PDP Context Response" },
      { GTP_MSG_DELETE_AA_PDP_REQ,  "Delete AA PDP Context Request" },
      { GTP_MSG_DELETE_AA_PDP_RESP, "Delete AA PDP Context Response" },
      { GTP_MSG_ERR_IND,                        "Error indication" },
      { GTP_MSG_PDU_NOTIFY_REQ,           "PDU notification request" },
      { GTP_MSG_PDU_NOTIFY_RESP,          "PDU notification response" },
      { GTP_MSG_PDU_NOTIFY_REJ_REQ, "PDU notification reject request" },
      { GTP_MSG_PDU_NOTIFY_REJ_RESP,      "PDU notification reject response" },
      { GTP_MSG_SUPP_EXT_HDR,             "Supported extension header notification" },
      { GTP_MSG_SEND_ROUT_INFO_REQ, "Send routing information for GPRS request" },
      { GTP_MSG_SEND_ROUT_INFO_RESP,      "Send routing information for GPRS response" },
      { GTP_MSG_FAIL_REP_REQ,             "Failure report request" },
      { GTP_MSG_FAIL_REP_RESP,            "Failure report response" },
      { GTP_MSG_MS_PRESENT_REQ,           "Note MS GPRS present request" },
      { GTP_MSG_MS_PRESENT_RESP,          "Note MS GPRS present response" },
      { GTP_MSG_IDENT_REQ,                "Identification request" },
      { GTP_MSG_IDENT_RESP,               "Identification response" },
      { GTP_MSG_SGSN_CNTXT_REQ,           "SGSN context request" },
      { GTP_MSG_SGSN_CNTXT_RESP,          "SGSN context response" },
      { GTP_MSG_SGSN_CNTXT_ACK,           "SGSN context acknowledgement" },
      { GTP_MSG_FORW_RELOC_REQ,           "Forward relocation request" },
      { GTP_MSG_FORW_RELOC_RESP,          "Forward relocation response" },
      { GTP_MSG_FORW_RELOC_COMP,          "Forward relocation complete" },
      { GTP_MSG_RELOC_CANCEL_REQ,         "Relocation cancel request" },
      { GTP_MSG_RELOC_CANCEL_RESP,  "Relocation cancel response" },
      { GTP_MSG_FORW_SRNS_CNTXT,          "Forward SRNS context" },
      { GTP_MSG_FORW_RELOC_ACK,           "Forward relocation complete acknowledge" },
      { GTP_MSG_FORW_SRNS_CNTXT_ACK,      "Forward SRNS context acknowledge" },
      { GTP_MSG_RAN_INFO_RELAY,           "RAN Information Relay" },
      { GTP_MBMS_NOTIFY_REQ,              "MBMS Notification Request" },
      { GTP_MBMS_NOTIFY_RES,              "MBMS Notification Response" },
      { GTP_MBMS_NOTIFY_REJ_REQ,          "MBMS Notification Reject Request" },
      { GTP_MBMS_NOTIFY_REJ_RES,          "MBMS Notification Reject Response" },
      { GTP_CREATE_MBMS_CNTXT_REQ,  "Create MBMS Context Request" },
      { GTP_CREATE_MBMS_CNTXT_RES,  "Create MBMS Context Response" },
      { GTP_UPD_MBMS_CNTXT_REQ,           "Update MBMS Context Request" },
      { GTP_UPD_MBMS_CNTXT_RES,           "Update MBMS Context Response" },
      { GTP_DEL_MBMS_CNTXT_REQ,           "Delete MBMS Context Request" },
      { GTP_DEL_MBMS_CNTXT_RES,           "Delete MBMS Context Response" },
      { GTP_MBMS_REG_REQ,                       "MBMS Registration Request" },
      { GTP_MBMS_REG_RES,                       "MBMS Registration Response" },
      { GTP_MBMS_DE_REG_REQ,              "MBMS De-Registration Request" },
      { GTP_MBMS_DE_REG_RES,              "MBMS De-Registration Response" },
      { GTP_MBMS_SES_START_REQ,           "MBMS Session Start Request" },
      { GTP_MBMS_SES_START_RES,           "MBMS Session Start Response" },
      { GTP_MBMS_SES_STOP_REQ,            "MBMS Session Stop Request" },
      { GTP_MBMS_SES_STOP_RES,            "MBMS Session Stop Response" },
      { GTP_MSG_DATA_TRANSF_REQ,          "Data record transfer request" },
      { GTP_MSG_DATA_TRANSF_RESP,         "Data record transfer response" },
      { GTP_MSG_TPDU,                           "T-PDU" },
      { 0, NULL }
};

/* definitions of fields in extension header */
#define GTP_EXT_CAUSE         0x01
#define GTP_EXT_IMSI          0x02
#define GTP_EXT_RAI                 0x03
#define GTP_EXT_TLLI          0x04
#define GTP_EXT_PTMSI         0x05
#define GTP_EXT_QOS_GPRS      0x06
#define GTP_EXT_REORDER       0x08
#define GTP_EXT_AUTH_TRI      0x09
#define GTP_EXT_MAP_CAUSE     0x0B
#define GTP_EXT_PTMSI_SIG     0x0C
#define GTP_EXT_MS_VALID      0x0D
#define GTP_EXT_RECOVER       0x0E
#define GTP_EXT_SEL_MODE      0x0F

#define GTP_EXT_16                  0x10
#define GTP_EXT_FLOW_LABEL    0x10
#define GTP_EXT_TEID          0x10  /* 0xFF10 3G */

#define GTP_EXT_17                  0x11
#define GTP_EXT_FLOW_SIG      0x11
#define GTP_EXT_TEID_CP       0x11  /* 0xFF11 3G */

#define GTP_EXT_18                  0x12
#define GTP_EXT_FLOW_II       0x12
#define GTP_EXT_TEID_II       0x12  /* 0xFF12 3G*/

#define GTP_EXT_19                  0x13
#define GTP_EXT_MS_REASON     0x13  /* same as 0x1D GTPv1_EXT_MS_REASON */
#define GTP_EXT_TEAR_IND      0x13  /* 0xFF13 3G*/

#define GTP_EXT_NSAPI         0x14  /* 3G */
#define GTP_EXT_RANAP_CAUSE   0x15  /* 3G */
#define GTP_EXT_RAB_CNTXT     0x16  /* 3G */
#define GTP_EXT_RP_SMS        0x17  /* 3G */
#define GTP_EXT_RP                  0x18  /* 3G */
#define GTP_EXT_PKT_FLOW_ID   0x19  /* 3G */
#define GTP_EXT_CHRG_CHAR     0x1A  /* 3G */
#define GTP_EXT_TRACE_REF     0x1B  /* 3G */
#define GTP_EXT_TRACE_TYPE    0x1C  /* 3G */
#define GTPv1_EXT_MS_REASON   0x1D  /* 3G */
#define GTP_EXT_TR_COMM       0x7E  /* charging */
#define GTP_EXT_CHRG_ID       0x7F
#define GTP_EXT_USER_ADDR     0x80
#define GTP_EXT_MM_CNTXT      0x81
#define GTP_EXT_PDP_CNTXT     0x82
#define GTP_EXT_APN                 0x83
#define GTP_EXT_PROTO_CONF    0x84
#define GTP_EXT_GSN_ADDR      0x85
#define GTP_EXT_MSISDN        0x86
#define GTP_EXT_QOS_UMTS      0x87  /* 3G */
#define GTP_EXT_AUTH_QUI      0x88  /* 3G */
#define GTP_EXT_TFT                 0x89  /* 3G */
#define GTP_EXT_TARGET_ID     0x8A  /* 3G */
#define GTP_EXT_UTRAN_CONT    0x8B  /* 3G */
#define GTP_EXT_RAB_SETUP     0x8C  /* 3G */
#define GTP_EXT_HDR_LIST      0x8D  /* 3G */
#define GTP_EXT_TRIGGER_ID    0x8E              /* 3G 142 7.7.41 */
#define GTP_EXT_OMC_ID        0x8F              /* 3G 143 TLV OMC Identity 7.7.42 */
#define GTP_EXT_RAN_TR_CONT               0x90  /* 3G 144 TLV RAN Transparent Container 7.7.43 */
#define GTP_EXT_PDP_CONT_PRIO       0x91  /* 3G 145 TLV PDP Context Prioritization 7.7.45 */
#define GTP_EXT_ADD_RAB_SETUP_INF   0x92  /* 3G 146 TLV Additional RAB Setup Information 7.7.45A */
#define GTP_EXT_SSGN_NO                   0x93  /* 3G 147 TLV SGSN Number 7.7.47 */
#define GTP_EXT_COMMON_FLGS               0x94  /* 3G 148 TLV Common Flags 7.7.48 */
#define GTP_EXT_APN_RES                   0x95  /* 3G 149 */
#define GTP_EXT_RA_PRIO_LCS               0x96  /* 3G 150 TLV Radio Priority LCS 7.7.25B */
#define GTP_EXT_RAT_TYPE                  0x97  /* 3G 151 TLV RAT Type 7.7.50 */
#define GTP_EXT_USR_LOC_INF               0x98  /* 3G 152 TLV User Location Information 7.7.51 */
#define GTP_EXT_MS_TIME_ZONE        0x99  /* 3G 153 TLV MS Time Zone 7.7.52 */

#define GTP_EXT_IMEISV                    0x9A  /* 3G */
#define GTP_EXT_CAMEL_CHG_INF_CON   0x9B  /* 3G 155 TLV CAMEL Charging Information Container 7.7.54 */
#define GTP_EXT_MBMS_UE_CTX               0x9C  /* 3G 156 TLV MBMS UE Context 7.7.55 */
#define GTP_EXT_TMGI                      0x9D  /* 3G 157 TLV Temporary Mobile Group Identity (TMGI) 7.7.56 */
#define GTP_EXT_RIM_RA                    0x9E  /* 3G 158 TLV RIM Routing Address 7.7.57 */
#define GTP_EXT_MBMS_PROT_CONF_OPT  0x9F  /* 3G 159 TLV MBMS Protocol Configuration Options 7.7.58 */
#define GTP_EXT_MBMS_SA                   0xA0  /* 3G 160 TLV MBMS Service Area 7.7.60 */
#define GTP_EXT_SRC_RNC_PDP_CTX_INF 0xA1  /* 3G 161 TLV Source RNC PDCP context info 7.7.61 */
#define GTP_EXT_ADD_TRS_INF               0xA2  /* 3G 162 TLV Additional Trace Info 7.7.62 */
#define GTP_EXT_HOP_COUNT                 0xA3  /* 3G 163 TLV Hop Counter 7.7.63 */
#define GTP_EXT_SEL_PLMN_ID               0xA4  /* 3G 164 TLV Selected PLMN ID 7.7.64 */
#define GTP_EXT_MBMS_SES_ID               0xA5  /* 3G 165 TLV MBMS Session Identifier 7.7.65 */
#define GTP_EXT_MBMS_2G_3G_IND            0xA6  /* 3G 166 TLV MBMS 2G/3G Indicator 7.7.66 */
#define GTP_EXT_ENH_NSAPI                 0xA7  /* 3G 167 TLV Enhanced NSAPI 7.7.67 */
#define GTP_EXT_MBMS_SES_DUR        0xA8  /* 3G 168 TLV MBMS Session Duration 7.7.59 */
#define GTP_EXT_ADD_MBMS_TRS_INF    0xA9  /* 3G 169 TLV Additional MBMS Trace Info 7.7.68 */
#define GTP_EXT_MBMS_SES_ID_REP_NO  0xAA  /* 3G 170 TLV MBMS Session Identity Repetition Number 7.7.69 */
#define GTP_EXT_MBMS_TIME_TO_DATA_TR 0xAB /* 3G 171 TLV MBMS Time To Data Transfer 7.7.70 */
#define GTP_EXT_PS_HO_REQ_CTX       0xAC  /* 3G 172 TLV PS Handover Request Context 7.7.71 */
#define GTP_EXT_BSS_CONT                  0xAD  /* 3G 173 TLV BSS Container 7.7.72 */
#define GTP_EXT_CELL_ID                   0xAE  /* 3G 174 TLV Cell Identification 7.7.73 */
#define GTP_EXT_PDU_NO                    0xAF  /* 3G 175 TLV PDU Numbers 7.7.74 */
#define GTP_EXT_BSSGP_CAUSE               0xA0  /* 3G 176 TLV BSSGP Cause 7.7.75 */

#define GTP_EXT_C1                  0xC1
#define GTP_EXT_C2                  0xC2
#define GTP_EXT_REL_PACK      0xF9  /* charging */
#define GTP_EXT_CAN_PACK      0xFA  /* charging */
#define GTP_EXT_CHRG_ADDR     0xFB
#define GTP_EXT_DATA_REQ      0xFC  /* charging */
#define GTP_EXT_DATA_RESP     0xFD  /* charging */
#define GTP_EXT_NODE_ADDR     0xFE  /* charging */
#define GTP_EXT_PRIV_EXT      0xFF

static const value_string gtp_val[] = {
      { GTP_EXT_CAUSE,        "Cause of operation" },
      { GTP_EXT_IMSI,               "IMSI" },
      { GTP_EXT_RAI,                "Routing Area Identity" },
      { GTP_EXT_TLLI,               "Temporary Logical Link Identity" },
      { GTP_EXT_PTMSI,        "Packet TMSI" },
      { GTP_EXT_QOS_GPRS,           "Quality of Service" },
      { GTP_EXT_REORDER,            "Reorder required" },
      { GTP_EXT_AUTH_TRI,           "Authentication triplets" },
      { GTP_EXT_MAP_CAUSE,    "MAP cause" },
      { GTP_EXT_PTMSI_SIG,    "P-TMSI signature" },
      { GTP_EXT_MS_VALID,           "MS validated" },
      { GTP_EXT_RECOVER,            "Recovery" },
      { GTP_EXT_SEL_MODE,           "Selection mode" },

      { GTP_EXT_16,                 "Flow label data I" },
      { GTP_EXT_FLOW_LABEL,   "Flow label data I" },
      { GTP_EXT_TEID,               "Tunnel Endpoint Identifier Data I" },                /* 3G */

      { GTP_EXT_17,                 "Flow label signalling" },
      { GTP_EXT_FLOW_SIG,           "Flow label signalling" },
      { GTP_EXT_TEID_CP,            "Tunnel Endpoint Identifier Data Control Plane" },    /* 3G */

      { GTP_EXT_18,                 "Flow label data II" },
      { GTP_EXT_FLOW_II,            "Flow label data II" },
      { GTP_EXT_TEID_II,            "Tunnel Endpoint Identifier Data II" },               /* 3G */

      { GTP_EXT_19,                 "MS not reachable reason" },
      { GTP_EXT_MS_REASON,    "MS not reachable reason" },
      { GTP_EXT_TEAR_IND,           "Teardown ID" },                                            /* 3G */
      
      { GTP_EXT_NSAPI,        "NSAPI" },                                                        /* 3G */
      { GTP_EXT_RANAP_CAUSE,  "RANAP cause" },                                            /* 3G */
      { GTP_EXT_RAB_CNTXT,    "RAB context" },                                            /* 3G */
      { GTP_EXT_RP_SMS,       "Radio Priority for MO SMS" },                              /* 3G */
      { GTP_EXT_RP,                 "Radio Priority" },                                               /* 3G */
      { GTP_EXT_PKT_FLOW_ID,  "Packet Flow ID" },                                               /* 3G */
      { GTP_EXT_CHRG_CHAR,    "Charging characteristics" },                         /* 3G */
      { GTP_EXT_TRACE_REF,    "Trace references" },                                       /* 3G */
      { GTP_EXT_TRACE_TYPE,   "Trace type" },                                                   /* 3G */
      { GTPv1_EXT_MS_REASON,  "MS not reachable reason" },                          /* 3G */
      { GTP_EXT_TR_COMM,            "Packet transfer command" },                          /* charging */
      { GTP_EXT_CHRG_ID,            "Charging ID" },
      { GTP_EXT_USER_ADDR,    "End user address" },
      { GTP_EXT_MM_CNTXT,           "MM context" },
      { GTP_EXT_PDP_CNTXT,    "PDP context" },
      { GTP_EXT_APN,                "Access Point Name" },
      { GTP_EXT_PROTO_CONF,   "Protocol configuration options" },
      { GTP_EXT_GSN_ADDR,           "GSN address" },
      { GTP_EXT_MSISDN,       "MS international PSTN/ISDN number" },
      { GTP_EXT_QOS_UMTS,           "Quality of service (UMTS)" },                              /* 3G */
      { GTP_EXT_AUTH_QUI,           "Authentication quintuplets" },                             /* 3G */
      { GTP_EXT_TFT,                "Traffic Flow Template (TFT)" },                      /* 3G */
      { GTP_EXT_TARGET_ID,    "Target (RNC) identification" },                      /* 3G */
      { GTP_EXT_UTRAN_CONT,   "UTRAN transparent field" },                          /* 3G */
      { GTP_EXT_RAB_SETUP,    "RAB setup information" },                                  /* 3G */
      { GTP_EXT_HDR_LIST,           "Extension Header Types List" },                      /* 3G */
      { GTP_EXT_TRIGGER_ID,   "Trigger Id" },                                                   /* 3G */
      { GTP_EXT_OMC_ID,       "OMC Identity" },                                           /* 3G */

      { GTP_EXT_RAN_TR_CONT,              "RAN Transparent Container" },                              /* 7.7.43 */
      { GTP_EXT_PDP_CONT_PRIO,            "PDP Context Prioritization" },                             /* 7.7.45 */
      { GTP_EXT_ADD_RAB_SETUP_INF,  "Additional RAB Setup Information" },                 /* 7.7.45A */
      { GTP_EXT_SSGN_NO,                        "SGSN Number" },                                            /* 7.7.47 */
      { GTP_EXT_COMMON_FLGS,              "Common Flags" },                                           /* 7.7.48 */
      { GTP_EXT_APN_RES,                        "APN Restriction" },                                        /* 3G */
      { GTP_EXT_RA_PRIO_LCS,              "Radio Priority LCS" },                                     /* 7.7.25B */
      { GTP_EXT_RAT_TYPE,                       "RAT Type" },                                                     /* 3G */
      { GTP_EXT_USR_LOC_INF,              "User Location Information" },                              /* 7.7.51 */
      { GTP_EXT_MS_TIME_ZONE,             "MS Time Zone" },                                           /* 7.7.52 */

      { GTP_EXT_IMEISV,                   "IMEI(SV)" },                                                     /* 3G */
      { GTP_EXT_CAMEL_CHG_INF_CON,  "CAMEL Charging Information Container" },       /* 7.7.54 */
      { GTP_EXT_MBMS_UE_CTX,              "MBMS UE Context" },                                        /* 7.7.55 */
      { GTP_EXT_TMGI,                           "Temporary Mobile Group Identity (TMGI)" },           /* 7.7.56 */
      { GTP_EXT_RIM_RA,                   "RIM Routing Address" },                                    /* 7.7.57 */
      { GTP_EXT_MBMS_PROT_CONF_OPT, "MBMS Protocol Configuration Options" },        /* 7.7.58 */
      { GTP_EXT_MBMS_SA,                        "MBMS Service Area" },                                      /* 7.7.60 */
      { GTP_EXT_SRC_RNC_PDP_CTX_INF,      "Source RNC PDCP context info" },                     /* 7.7.61 */
      { GTP_EXT_ADD_TRS_INF,              "Additional Trace Info" },                                  /* 7.7.62 */
      { GTP_EXT_HOP_COUNT,                      "Hop Counter" },                                      /* 7.7.63 */
      { GTP_EXT_SEL_PLMN_ID,              "Selected PLMN ID" },                                       /* 7.7.64 */
      { GTP_EXT_MBMS_SES_ID,              "MBMS Session Identifier" },                          /* 7.7.65 */
      { GTP_EXT_MBMS_2G_3G_IND,           "MBMS 2G/3G Indicator" },                                   /* 7.7.66 */
      { GTP_EXT_ENH_NSAPI,                "Enhanced NSAPI" },                                               /* 7.7.67 */
      { GTP_EXT_MBMS_SES_DUR,             "MBMS Session Duration" },                                  /* 7.7.59 */
      { GTP_EXT_ADD_MBMS_TRS_INF,         "Additional MBMS Trace Info" },                             /* 7.7.68 */
      { GTP_EXT_MBMS_SES_ID_REP_NO, "MBMS Session Identity Repetition Number" },    /* 7.7.69 */
      { GTP_EXT_MBMS_TIME_TO_DATA_TR,     "MBMS Time To Data Transfer" },                             /* 7.7.70 */
      { GTP_EXT_PS_HO_REQ_CTX,            "PS Handover Request Context" },                      /* 7.7.71 */
      { GTP_EXT_BSS_CONT,                       "BSS Container" },                                                /* 7.7.72 */
      { GTP_EXT_CELL_ID,                        "Cell Identification" },                                    /* 7.7.73 */
      { GTP_EXT_PDU_NO,                   "PDU Numbers" },                                            /* 7.7.74 */
      { GTP_EXT_BSSGP_CAUSE,              "BSSGP Cause" },                                            /* 7.7.75 */
      { GTP_EXT_REL_PACK,                       "Sequence numbers of released packets IE" },    /* charging */
      { GTP_EXT_CAN_PACK,                       "Sequence numbers of canceled packets IE" },    /* charging */
      { GTP_EXT_CHRG_ADDR,                "Charging Gateway address" }, 
      { GTP_EXT_DATA_REQ,                       "Data record packet" },                                     /* charging */
      { GTP_EXT_DATA_RESP,                "Requests responded" },                                     /* charging */
      { GTP_EXT_NODE_ADDR,                "Address of recommended node" },                      /* charging */
      { GTP_EXT_PRIV_EXT,                 "Private Extension" },
      { 0, NULL }
};
/* It seems like some IE's are renamed in gtpv1 at least reading 
 * 3GPP TS 29.060 version 6.11.0 Release 6
 */ 
static const value_string gtpv1_val[] = {
      { GTP_EXT_CAUSE,        "Cause of operation" },
      { GTP_EXT_IMSI,               "IMSI" },
      { GTP_EXT_RAI,                "Routing Area Identity" },
      { GTP_EXT_TLLI,               "Temporary Logical Link Identity" },
      { GTP_EXT_PTMSI,        "Packet TMSI" },
      { GTP_EXT_QOS_GPRS,           "Quality of Service" },
      { GTP_EXT_REORDER,            "Reorder required" },
      { GTP_EXT_AUTH_TRI,           "Authentication triplets" },
      { GTP_EXT_MAP_CAUSE,    "MAP cause" },
      { GTP_EXT_PTMSI_SIG,    "P-TMSI signature" },
      { GTP_EXT_MS_VALID,           "MS validated" },
      { GTP_EXT_RECOVER,            "Recovery" },
      { GTP_EXT_SEL_MODE,           "Selection mode" },

      { GTP_EXT_TEID,               "Tunnel Endpoint Identifier Data I" },                /* 3G */

      { GTP_EXT_TEID_CP,            "Tunnel Endpoint Identifier Data Control Plane" },    /* 3G */

      { GTP_EXT_TEID_II,            "Tunnel Endpoint Identifier Data II" },               /* 3G */

      { GTP_EXT_TEAR_IND,           "Teardown ID" },                                            /* 3G */
      
      { GTP_EXT_NSAPI,        "NSAPI" },                                                        /* 3G */
      { GTP_EXT_RANAP_CAUSE,  "RANAP cause" },                                            /* 3G */
      { GTP_EXT_RAB_CNTXT,    "RAB context" },                                            /* 3G */
      { GTP_EXT_RP_SMS,       "Radio Priority for MO SMS" },                              /* 3G */
      { GTP_EXT_RP,                 "Radio Priority" },                                               /* 3G */
      { GTP_EXT_PKT_FLOW_ID,  "Packet Flow ID" },                                               /* 3G */
      { GTP_EXT_CHRG_CHAR,    "Charging characteristics" },                         /* 3G */
      { GTP_EXT_TRACE_REF,    "Trace references" },                                       /* 3G */
      { GTP_EXT_TRACE_TYPE,   "Trace type" },                                                   /* 3G */
      { GTPv1_EXT_MS_REASON,  "MS not reachable reason" },                          /* 3G */
      { GTP_EXT_TR_COMM,            "Packet transfer command" },                          /* charging */
      { GTP_EXT_CHRG_ID,            "Charging ID" },
      { GTP_EXT_USER_ADDR,    "End user address" },
      { GTP_EXT_MM_CNTXT,           "MM context" },
      { GTP_EXT_PDP_CNTXT,    "PDP context" },
      { GTP_EXT_APN,                "Access Point Name" },
      { GTP_EXT_PROTO_CONF,   "Protocol configuration options" },
      { GTP_EXT_GSN_ADDR,           "GSN address" },
      { GTP_EXT_MSISDN,       "MS international PSTN/ISDN number" },
      { GTP_EXT_QOS_UMTS,           "Quality of service (UMTS)" },                              /* 3G */
      { GTP_EXT_AUTH_QUI,           "Authentication quintuplets" },                             /* 3G */
      { GTP_EXT_TFT,                "Traffic Flow Template (TFT)" },                      /* 3G */
      { GTP_EXT_TARGET_ID,    "Target (RNC) identification" },                      /* 3G */
      { GTP_EXT_UTRAN_CONT,   "UTRAN transparent field" },                          /* 3G */
      { GTP_EXT_RAB_SETUP,    "RAB setup information" },                                  /* 3G */
      { GTP_EXT_HDR_LIST,           "Extension Header Types List" },                      /* 3G */
      { GTP_EXT_TRIGGER_ID,   "Trigger Id" },                                                   /* 3G */
      { GTP_EXT_OMC_ID,       "OMC Identity" },                                           /* 3G */

      { GTP_EXT_RAN_TR_CONT,              "RAN Transparent Container" },                              /* 7.7.43 */
      { GTP_EXT_PDP_CONT_PRIO,            "PDP Context Prioritization" },                             /* 7.7.45 */
      { GTP_EXT_ADD_RAB_SETUP_INF,  "Additional RAB Setup Information" },                 /* 7.7.45A */
      { GTP_EXT_SSGN_NO,                        "SGSN Number" },                                            /* 7.7.47 */
      { GTP_EXT_COMMON_FLGS,              "Common Flags" },                                           /* 7.7.48 */
      { GTP_EXT_APN_RES,                        "APN Restriction" },                                        /* 3G */
      { GTP_EXT_RA_PRIO_LCS,              "Radio Priority LCS" },                                     /* 7.7.25B */
      { GTP_EXT_RAT_TYPE,                       "RAT Type" },                                                     /* 3G */
      { GTP_EXT_USR_LOC_INF,              "User Location Information" },                              /* 7.7.51 */
      { GTP_EXT_MS_TIME_ZONE,             "MS Time Zone" },                                           /* 7.7.52 */

      { GTP_EXT_IMEISV,                   "IMEI(SV)" },                                                     /* 3G */
      { GTP_EXT_CAMEL_CHG_INF_CON,  "CAMEL Charging Information Container" },       /* 7.7.54 */
      { GTP_EXT_MBMS_UE_CTX,              "MBMS UE Context" },                                        /* 7.7.55 */
      { GTP_EXT_TMGI,                           "Temporary Mobile Group Identity (TMGI)" },           /* 7.7.56 */
      { GTP_EXT_RIM_RA,                   "RIM Routing Address" },                                    /* 7.7.57 */
      { GTP_EXT_MBMS_PROT_CONF_OPT, "MBMS Protocol Configuration Options" },        /* 7.7.58 */
      { GTP_EXT_MBMS_SA,                        "MBMS Service Area" },                                      /* 7.7.60 */
      { GTP_EXT_SRC_RNC_PDP_CTX_INF,      "Source RNC PDCP context info" },                     /* 7.7.61 */
      { GTP_EXT_ADD_TRS_INF,              "Additional Trace Info" },                                  /* 7.7.62 */
      { GTP_EXT_HOP_COUNT,                      "Hop Counter" },                                      /* 7.7.63 */
      { GTP_EXT_SEL_PLMN_ID,              "Selected PLMN ID" },                                       /* 7.7.64 */
      { GTP_EXT_MBMS_SES_ID,              "MBMS Session Identifier" },                          /* 7.7.65 */
      { GTP_EXT_MBMS_2G_3G_IND,           "MBMS 2G/3G Indicator" },                                   /* 7.7.66 */
      { GTP_EXT_ENH_NSAPI,                "Enhanced NSAPI" },                                               /* 7.7.67 */
      { GTP_EXT_MBMS_SES_DUR,             "MBMS Session Duration" },                                  /* 7.7.59 */
      { GTP_EXT_ADD_MBMS_TRS_INF,         "Additional MBMS Trace Info" },                             /* 7.7.68 */
      { GTP_EXT_MBMS_SES_ID_REP_NO, "MBMS Session Identity Repetition Number" },    /* 7.7.69 */
      { GTP_EXT_MBMS_TIME_TO_DATA_TR,     "MBMS Time To Data Transfer" },                             /* 7.7.70 */
      { GTP_EXT_PS_HO_REQ_CTX,            "PS Handover Request Context" },                      /* 7.7.71 */
      { GTP_EXT_BSS_CONT,                       "BSS Container" },                                                /* 7.7.72 */
      { GTP_EXT_CELL_ID,                        "Cell Identification" },                                    /* 7.7.73 */
      { GTP_EXT_PDU_NO,                   "PDU Numbers" },                                            /* 7.7.74 */
      { GTP_EXT_BSSGP_CAUSE,              "BSSGP Cause" },                                            /* 7.7.75 */
      { GTP_EXT_REL_PACK,                       "Sequence numbers of released packets IE" },    /* charging */
      { GTP_EXT_CAN_PACK,                       "Sequence numbers of canceled packets IE" },    /* charging */
      { GTP_EXT_CHRG_ADDR,                "Charging Gateway address" }, 
      { GTP_EXT_DATA_REQ,                       "Data record packet" },                                     /* charging */
      { GTP_EXT_DATA_RESP,                "Requests responded" },                                     /* charging */
      { GTP_EXT_NODE_ADDR,                "Address of recommended node" },                      /* charging */
      { GTP_EXT_PRIV_EXT,                 "Private Extension" },
      { 0, NULL }
};
/* GPRS:    9.60 v7.6.0, page 37
 * UMTS:    29.060 v4.0, page 45
 */
static const value_string cause_type[] = {
      { 0,  "Request IMSI" },
      { 1,  "Request IMEI" },
      { 2,  "Request IMSI and IMEI" },
      { 3,  "No identity needed" },
      { 4,  "MS refuses" },
      { 5,  "MS is not GPRS responding" },
      { 59, "System failure" },     /* charging */
      { 60, "The transmit buffers are becoming full" },     /* charging */
      { 61, "The receive buffers are becoming full" },      /* charging */
      { 62, "Another node is about to go down" },     /* charging */
      { 63, "This node is about to go down" },  /* charging */
      { 128,      "Request accepted" },
      { 192,      "Non-existent" },
      { 193,      "Invalid message format" },
      { 194,      "IMSI not known" },
      { 195,      "MS is GPRS detached" },
      { 196,      "MS is not GPRS responding" },
      { 197,      "MS refuses" },
      { 198,      "Version not supported" },
      { 199,      "No resource available" },
      { 200,      "Service not supported" },
      { 201,      "Mandatory IE incorrect" },
      { 202,      "Mandatory IE missing" },
      { 203,      "Optional IE incorrect" },
      { 204,      "System failure" },
      { 205,      "Roaming restriction" },
      { 206,      "P-TMSI signature mismatch" },
      { 207,      "GPRS connection suspended" },
      { 208,      "Authentication failure" },
      { 209,      "User authentication failed" },
      { 210,      "Context not found" },
      { 211,      "All PDP dynamic addresses are occupied" },
      { 212,      "No memory is available" },
      { 213,      "Relocation failure" },
      { 214,      "Unknown mandatory extension header" },
      { 215,      "Semantic error in the TFT operation" },
      { 216,      "Syntactic error in the TFT operation" },
      { 217,      "Semantic errors in packet filter(s)" },
      { 218,      "Syntactic errors in packet filter(s)" },
      { 219,      "Missing or unknown APN" },
      { 220,      "Unknown PDP address or PDP type" },
      { 221,      "PDP context without TFT already activated" },
      { 222,      "APN access denied - no subscription" },
      { 223,      "APN Restriction type incompatibility with currently active PDP Contexts" },
      { 224,      "MS MBMS Capabilities Insufficient" },
      { 252,      "Request related to possibly duplicated packets already fulfilled" },   /* charging */
      { 253,      "Request already fulfilled" },      /* charging */
      { 254,      "Sequence numbers of released/cancelled packets IE incorrect" },  /* charging */
      { 255,      "Request not fulfilled" },    /* charging */
      { 0, NULL }
};

/* GPRS:    9.02 v7.7.0
 * UMTS:    29.002 v4.2.1, chapter 17.5, page 268
 * Imported gsm_map_LocalErrorcode_vals from gsm_map
 */

static const value_string gsn_addr_type[] = {
      { 0x00, "IPv4" },
      { 0x01, "IPv6" },
      { 0,  NULL },
};

static const value_string pdp_type[] = {
      { 0x00, "X.25" },
      { 0x01, "PPP" },
      { 0x02, "OSP:IHOSS" },
      { 0x21, "IPv4" },
      { 0x57, "IPv6" },
      { 0, NULL }
};

static const value_string pdp_org_type[] = {
      { 0, "ETSI" },
      { 1, "IETF" },
      { 0, NULL }
};

static const value_string qos_delay_type[] = {
      { 0x00, "Subscribed delay class (in MS to network direction)" },
      { 0x01, "Delay class 1" },
      { 0x02, "Delay class 2" },
      { 0x03, "Delay class 3" },
      { 0x04, "Delay class 4 (best effort)" },
      { 0x07,     "Reserved" },
      { 0, NULL }
};

static const value_string qos_reliability_type[] = {
      { 0x00, "Subscribed reliability class (in MS to network direction)" },
      { 0x01, "Ack GTP/LLC/RLC, Protected data" },
      { 0x02, "Unack GTP, Ack LLC/RLC, Protected data" },
      { 0x03, "Unack GTP/LLC, Ack RLC, Protected data" },
      { 0x04, "Unack GTP/LLC/RLC, Protected data" },
      { 0x05, "Unack GTP/LLC/RLC, Unprotected data" },
      { 0x07, "Reserved" },
      { 0, NULL }
};

static const value_string qos_peak_type[] = {
      { 0x00, "Subscribed peak throughput (in MS to network direction)" },
      { 0x01, "Up to 1 000 oct/s" },
      { 0x02, "Up to 2 000 oct/s" },
      { 0x03, "Up to 4 000 oct/s" },
      { 0x04, "Up to 8 000 oct/s" },
      { 0x05, "Up to 16 000 oct/s" },
      { 0x06, "Up to 32 000 oct/s" },
      { 0x07, "Up to 64 000 oct/s" },
      { 0x08, "Up to 128 000 oct/s" },
      { 0x09, "Up to 256 000 oct/s" },
/* QoS Peak throughput classes from 0x0A to 0x0F (from 10 to 15) are subscribed */
      { 0x0A,     "Reserved" },
      { 0x0B,     "Reserved" },
      { 0x0C,     "Reserved" },
      { 0x0D,     "Reserved" },
      { 0x0E,     "Reserved" },
      { 0x0F,     "Reserved" },
      { 0, NULL }
};

static const value_string qos_precedence_type[] = {
      { 0x00, "Subscribed precedence (in MS to network direction)" },
      { 0x01, "High priority" },
      { 0x02, "Normal priority" },
      { 0x03, "Low priority" },
      { 0x07, "Reserved" },
      { 0, NULL }
};

static const value_string qos_mean_type[] = {
      { 0x00, "Subscribed mean throughput (in MS to network direction)" },
      { 0x01, "100 oct/h" },        /* Class 2 */
      { 0x02, "200 oct/h" },        /* Class 3 */
      { 0x03, "500 oct/h" },        /* Class 4 */
      { 0x04, "1 000 oct/h" },      /* Class 5 */
      { 0x05, "2 000 oct/h" },      /* Class 6 */
      { 0x06, "5 000 oct/h" },      /* Class 7 */
      { 0x07, "10 000 oct/h" },     /* Class 8 */
      { 0x08, "20 000 oct/h" },     /* Class 9 */
      { 0x09, "50 000 oct/h" },     /* Class 10 */
      { 0x0A, "100 000 oct/h" },    /* Class 11 */
      { 0x0B, "200 000 oct/h" },    /* Class 12 */
      { 0x0C, "500 000 oct/h" },    /* Class 13 */
      { 0x0D, "1 000 000 oct/h" },  /* Class 14 */
      { 0x0E, "2 000 000 oct/h" },  /* Class 15 */
      { 0x0F, "5 000 000 oct/h" },  /* Class 16 */
      { 0x10, "10 000 000 oct/h" }, /* Class 17 */
      { 0x11, "20 000 000 oct/h" }, /* Class 18 */
      { 0x12, "50 000 000 oct/h" }, /* Class 19 */
/* QoS Mean throughput classes from 0x13 to 0x1E (from 19 to 30) are subscribed */
      { 0x13, "Reserved" },
      { 0x14, "Reserved" },
      { 0x15, "Reserved" },
      { 0x16, "Reserved" },
      { 0x17, "Reserved" },
      { 0x18, "Reserved" },
      { 0x19, "Reserved" },
      { 0x1A, "Reserved" },
      { 0x1B, "Reserved" },
      { 0x1C, "Reserved" },
      { 0x1D, "Reserved" },
      { 0x1E, "Reserved" },
      { 0x1F, "Best effort" },      /* Class 1 */
      { 0, NULL }
};

static const value_string qos_del_err_sdu[] = {
      { 0x00, "Subscribed delivery of erroneous SDUs (in MS to network direction)" },
      { 0x01, "No detect ('-')" },
      { 0x02, "Erroneous SDUs are delivered ('yes')" },
      { 0x03, "Erroneous SDUs are not delivered ('no')" },
      { 0x07, "Reserved" },         /* All other values are reserved */
      { 0, NULL }
};

static const value_string qos_del_order[] = {
      { 0x00, "Subscribed delivery order (in MS to network direction)" },
      { 0x01, "With delivery order ('yes')" },
      { 0x02, "Without delivery order ('no')" },
      { 0x03, "Reserved" },         /* All other values are reserved */
      { 0, NULL }
};

static const value_string qos_traf_class[] = {
      { 0x00, "Subscribed traffic class (in MS to network direction)" },
      { 0x01, "Conversational class" },
      { 0x02, "Streaming class" },
      { 0x03, "Interactive class" },
      { 0x04, "Background class" },
      { 0x07, "Reserved" },         /* All other values are reserved */
      { 0, NULL }
};

static const value_string qos_max_sdu_size[] = {
      { 0x00, "Subscribed maximum SDU size (in MS to network direction" },
      /* For values from 0x01 to 0x96 (from 1 to 150), use a granularity of 10 octets */
      { 0x97, "1502 octets" },
      { 0x98, "1510 octets" },
      { 0x99, "1520 octets" },
      { 0, NULL }                         /* All other values are reserved */
};

static const value_string qos_max_ul[] = {
      { 0x00, "Subscribed maximum bit rate for uplink (in MS to network direction)" },
      /* For values from 0x01 to 0x3F (from 1 to 63), use a granularity of 1 kbps */
      /* For values from 0x40 to 0x7F, value = 64 kbps + (value - 0x40) * 8 kbps */
      /* For values from 0x80 to 0xFE, value = 576 kbps + (value - 0x80) * 64 kbps */
      { 0xFF, "0 kbps" },
      { 0, NULL }
};

static const value_string qos_max_dl[] = {
      { 0x00, "Subscribed maximum bit rate for downlink (in MS to network direction)" },
      /* For values from 0x01 to 0x3F (from 1 to 63), use a granularity of 1 kbps */
      /* For values from 0x40 to 0x7F, value = 64 kbps + (value - 0x40) * 8 kbps */
      /* For values from 0x80 to 0xFE, value = 576 kbps + (value - 0x80) * 64 kbps */
      { 0xFF, "0 kbps" },
      { 0, NULL }
};

static const value_string qos_res_ber[] = {
      { 0x00, "Subscribed residual BER (in MS to network direction)" },
      { 0x01, "1/20 = 5x10^-2" },
      { 0x02, "1/100 = 1x10^-2" },
      { 0x03, "1/200 = 5x10^-3" },
      { 0x04, "1/250 = 4x10^-3" },
      { 0x05, "1/1 000 = 1x10^-3" },
      { 0x06, "1/10 000 = 1x10^-4" },
      { 0x07, "1/100 000 = 1x10^-5" },
      { 0x08, "1/1 000 000 = 1x10^-6" },
      { 0x09, "3/50 000 000 = 6x10^-8" },
      { 0x0F, "Reserved" },         /* All other values are reserved */
      { 0, NULL }
};

static const value_string qos_sdu_err_ratio[] = {
      { 0x00, "Subscribed SDU error ratio (in MS to network direction)" },
      { 0x01, "1/100 = 1x10^-2" },
      { 0x02, "7/1000 = 7x10^-3" },
      { 0x03, "1/1 000 = 1x10^-3" },
      { 0x04, "1/10 000 = 1x10^-4" },
      { 0x05, "1/100 000 = 1x10^-5" },
      { 0x06, "1/1 000 000 = 1x10^-6" },
      { 0x07, "1/10 = 1x10^-1" },
      { 0x0F, "Reserved" },         /* All other values are reserved */
      { 0, NULL }
};

static const value_string qos_traf_handl_prio[] = {
      { 0x00, "Subscribed traffic handling priority (in MS to network direction)" },
      { 0x01, "Priority level 1" },
      { 0x02, "Priority level 2" },
      { 0x03, "Priority level 3" },
      { 0, NULL }
};

static const value_string qos_trans_delay[] = {
      { 0x00, "Subscribed Transfer Delay (in MS to network direction)" },
      { 0x01, "10 ms" },      /* Using a granularity of 10 ms */
      { 0x02, "20 ms" },
      { 0x03, "30 ms" },
      { 0x04, "40 ms" },
      { 0x05, "50 ms" },
      { 0x06, "60 ms" },
      { 0x07, "70 ms" },
      { 0x08, "80 ms" },
      { 0x09, "90 ms" },
      { 0x0A, "100 ms" },
      { 0x0B, "110 ms" },
      { 0x0C, "120 ms" },
      { 0x0D, "130 ms" },
      { 0x0E, "140 ms" },
      { 0x0F, "150 ms" },
      { 0x10, "200 ms" },     /* (For values from 0x10 to 0x1F, value = 200 ms + (value - 0x10) * 50 ms */
      { 0x11, "250 ms" },
      { 0x12, "300 ms" },
      { 0x13, "350 ms" },
      { 0x14, "400 ms" },
      { 0x15, "450 ms" },
      { 0x16, "500 ms" },
      { 0x17, "550 ms" },
      { 0x18, "600 ms" },
      { 0x19, "650 ms" },
      { 0x1A, "700 ms" },
      { 0x1B, "750 ms" },
      { 0x1C, "800 ms" },
      { 0x1D, "850 ms" },
      { 0x1E, "900 ms" },
      { 0x1F, "950 ms" },
      { 0x20, "1000 ms" },    /* For values from 0x20 to 0x3E, value = 1000 ms + (value - 0x20) * 100 ms */
      { 0x21, "1100 ms" },
      { 0x22, "1200 ms" },
      { 0x23, "1300 ms" },
      { 0x24, "1400 ms" },
      { 0x25, "1500 ms" },
      { 0x26, "1600 ms" },
      { 0x27, "1700 ms" },
      { 0x28, "1800 ms" },
      { 0x29, "1900 ms" },
      { 0x2A, "2000 ms" },
      { 0x2B, "2100 ms" },
      { 0x2C, "2200 ms" },
      { 0x2D, "2300 ms" },
      { 0x2E, "2400 ms" },
      { 0x2F, "2500 ms" },
      { 0x30, "2600 ms" },
      { 0x31, "2700 ms" },
      { 0x32, "2800 ms" },
      { 0x33, "2900 ms" },
      { 0x34, "3000 ms" },
      { 0x35, "3100 ms" },
      { 0x36, "3200 ms" },
      { 0x37, "3300 ms" },
      { 0x38, "3400 ms" },
      { 0x39, "3500 ms" },
      { 0x3A, "3600 ms" },
      { 0x3B, "3700 ms" },
      { 0x3C, "3800 ms" },
      { 0x3D, "3900 ms" },
      { 0x3E, "4000 ms" },
      { 0x3F, "Reserved"},
      { 0, NULL }
};

static const value_string qos_guar_ul[] = {
      { 0x00, "Subscribed guaranteed bit rate for uplink (in MS to network direction)" },
      /* For values from 0x01 to 0x3F (from 1 to 63), use a granularity of 1 kbps */
      /* For values from 0x40 to 0x7F, value = 64 kbps + (value - 0x40) * 8 kbps */
      /* For values from 0x80 to 0xFE, value = 576 kbps + (value - 0x80) * 64 kbps */
      { 0xFF, "0 kbps" },
      { 0, NULL }
};

static const value_string qos_guar_dl[] = {
      { 0x00, "Subscribed guaranteed bit rate for downlink (in MS to network direction)" },
      /* For values from 0x01 to 0x3F (from 1 to 63), use a granularity of 1 kbps */
      /* For values from 0x40 to 0x7F, value = 64 kbps + (value - 0x40) * 8 kbps */
      /* For values from 0x80 to 0xFE, value = 576 kbps + (value - 0x80) * 64 kbps */
      { 0xFF, "0 kbps" },
      { 0, NULL }
};

static const value_string sel_mode_type[] = {
      { 0,  "MS or network provided APN, subscribed verified" },
      { 1,  "MS provided APN, subscription not verified" },
      { 2,  "Network provided APN, subscription not verified" },
      { 3,  "For future use (Network provided APN, subscription not verified" },/* Shall not be sent. If received, shall be sent as value 2 */
      { 0,  NULL }
};

static const value_string tr_comm_type[] = {
      { 1,  "Send data record packet" },
      { 2,  "Send possibly duplicated data record packet" },
      { 3,  "Cancel data record packet" },
      { 4,  "Release data record packet"},
      { 0,  NULL }
};

/* TODO: CHeck if all ms_reasons are included */
static const value_string ms_not_reachable_type[] = {
      { 0,  "No paging response via the MSC" },
      { 1,  "IMSI detached" },
      { 2,  "Roaming restriction" },
      { 3,  "Deregistered in the HLR for non GPRS" },
      { 4,  "MS purge for non GPRS" },
      { 5,  "No paging response via the SGSN" },
      { 6,  "GPRS detached" },
      { 7,  "Deregistered in the HLR for non GPRS" },
      { 8,  "MS purged for GPRS" },
      { 9,  "Unidentified subscriber via the MSC" },
      { 10, "Unidentified subscriber via the SGSN" },
      { 0,  NULL }
};

/* UMTS:    25.413 v3.4.0, chapter 9.2.1.4, page 80
 */
static const value_string ranap_cause_type[] = {
/* Radio Network Layer Cause (1-->64) */
      { 1, "RAB preempted" },
      { 2, "Trelocoverall Expiry" },
      { 3, "Trelocprep Expiry" },
      { 4, "Treloccomplete Expiry" },
      { 5, "Tqueing Expiry" },
      { 6, "Relocation Triggered" },
      { 7, "TRELOCalloc Expiry" },
      { 8, "Unable to Estabish During Relocation" },
      { 9, "Unknown Target RNC" },
      { 10, "Relocation Cancelled" },
      { 11, "Successful Relocation" },
      { 12, "Requested Ciphering and/or Integrity Protection Algorithms not Supported" },
      { 13, "Change of Ciphering and/or Integrity Protection is not supported" },
      { 14, "Failure in the Radio Interface Procedure" },
      { 15, "Release due to UTRAN Generated Reason" },
      { 16, "User Inactivity" },
      { 17, "Time Critical Relocation" },
      { 18, "Requested Traffic Class not Available" },
      { 19, "Invalid RAB Parameters Value" },
      { 20, "Requested Maximum Bit Rate not Available" },
      { 21, "Requested Guaranteed Bit Rate not Available" },
      { 22, "Requested Transfer Delay not Achievable" },
      { 23, "Invalid RAB Parameters Combination" },
      { 24, "Condition Violation for SDU Parameters" },
      { 25, "Condition Violation for Traffic Handling Priority" },
      { 26, "Condition Violation for Guaranteed Bit Rate" },
      { 27, "User Plane Versions not Supported" },
      { 28, "Iu UP Failure" },
      { 29, "Relocation Failure in Target CN/RNC or Target System" },
      { 30, "Invalid RAB ID" },
      { 31, "No Remaining RAB" },
      { 32, "Interaction with other procedure" },
      { 33, "Requested Maximum Bit Rate for DL not Available" },
      { 34, "Requested Maximum Bit Rate for UL not Available" },
      { 35, "Requested Guaranteed Bit Rate for DL not Available" },
      { 36, "Requested Guaranteed Bit Rate for UL not Available" },
      { 37, "Repeated Integrity Checking Failure" },
      { 38, "Requested Report Type not supported" },
      { 39, "Request superseded" },
      { 40, "Release due to UE generated signalling connection release" },
      { 41, "Resource Optimisation Relocation" },
      { 42, "Requested Information Not Available" },
      { 43, "Relocation desirable for radio reasons" },
      { 44, "Relocation not supported in Target RNC or Target System" },
      { 45, "Directed Retry" },
      { 46, "Radio Connection With UE Lost" },
      {  47, "rNC-unable-to-establish-all-RFCs" },
      {  48, "deciphering-keys-not-available" },
      {  49, "dedicated-assistance-data-not-available" },
      {  50, "relocation-target-not-allowed" },
      {  51, "location-reporting-congestion" },
      {  52, "reduce-load-in-serving-cell" },
      {  53, "no-radio-resources-available-in-target-cell" },
      {  54, "gERAN-Iumode-failure" },
      {  55, "access-restricted-due-to-shared-networks" },
      {  56, "incoming-relocation-not-supported-due-to-PUESBINE-feature" },
      {  57, "traffic-load-in-the-target-cell-higher-than-in-the-source-cell" },
      {  58, "mBMS-no-multicast-service-for-this-UE" },
      {  59, "mBMS-unknown-UE-ID" },
      {  60, "successful-MBMS-session-start-no-data-bearer-necessary" },
      {  61, "mBMS-superseded-due-to-NNSF" },
      {  62, "mBMS-UE-linking-already-done" },
      {  63, "mBMS-UE-de-linking-failure-no-existing-UE-linking" },
      {  64, "tMGI-unknown" },
/* Transport Layer Cause (65-->80) */
      { 65, "Signalling Transport Resource Failure" },
      { 66, "Iu Transport Connection Failed to Establish" },
/* NAS Cause (81-->96) */
      { 81, "User Restriction Start Indication" },
      { 82, "User Restriction End Indication" },
      { 83, "Normal Release" },
/* Protocol Cause (97-->112) */
      { 97, "Transfer Syntax Error" },
      { 98, "Semantic Error" },
      { 99, "Message not compatible with receiver state" },
      { 100, "Abstract Syntax Error (Reject)" },
      { 101, "Abstract Syntax Error (Ignore and Notify)" },
      { 102, "Abstract Syntax Error (Falsely Constructed Message" },
/* Miscellaneous Cause (113-->128) */
      { 113, "O & M Intervention" },
      { 114, "No Resource Available" },
      { 115, "Unspecified Failure" },
      { 116, "Network Opimisation" },
/* Non-standard Cause (129-->255) */

/* ranap_CauseRadioNetworkExtension ??
      { 257, "iP-multicast-address-and-APN-not-valid" },
      { 258, "mBMS-de-registration-rejected-due-to-implicit-registration" },
      { 259, "mBMS-request-superseded" },
      { 260, "mBMS-de-registration-during-session-not-allowed" },
      { 261, "mBMS-no-data-bearer-necessary" },
  */

      { 0, NULL }
};

static const value_string mm_sec_modep[] = {
      { 0,  "Used cipher value, UMTS keys and Quintuplets" },
      { 1,  "GSM key and triplets" },
      { 2,  "UMTS key and quintuplets" },
      { 3,  "GSM key and quintuplets" },
      { 0,  NULL }
};

static const value_string gtp_cipher_algorithm[] = {
      { 0, "No ciphering" },
      { 1, "GEA/1" },
      { 2, "GEA/2" },
      { 3, "GEA/3" },
      { 4, "GEA/4" },
      { 5, "GEA/5" },
      { 6, "GEA/6" },
      { 7, "GEA/7" },
      { 0, NULL }
};

static const value_string gtp_ext_rat_type_vals[] = {
      { 0,  "Reserved" },
      { 1,  "UTRAN" },
      { 2,  "GERAN" },
      { 3,  "WLAN" },
      { 0,  NULL }
};



#define MM_PROTO_GROUP_CALL_CONTROL 0x00
#define MM_PROTO_BROADCAST_CALL_CONTROL   0x01
#define MM_PROTO_PDSS1              0x02
#define MM_PROTO_CALL_CONTROL       0x03
#define MM_PROTO_PDSS2              0x04
#define MM_PROTO_MM_NON_GPRS        0x05
#define MM_PROTO_RR_MGMT            0x06
#define MM_PROTO_MM_GPRS            0x08
#define MM_PROTO_SMS                0x09
#define MM_PROTO_SESSION_MGMT       0x0A
#define MM_PROTO_NON_CALL_RELATED   0x0B

static const value_string tft_code_type[] = {
      { 0, "Spare" },
      { 1, "Create new TFT" },
      { 2, "Delete existing TFT" },
      { 3, "Add packet filters to existing TFT" },
      { 4, "Replace packet filters in existing TFT" },
      { 5, "Delete packet filters from existing TFT" },
      { 6, "Reserved" },
      { 7, "Reserved" },
      { 0, NULL }
};


static dissector_handle_t ip_handle;
static dissector_handle_t ipv6_handle;
static dissector_handle_t ppp_handle;
static dissector_handle_t data_handle;
static dissector_handle_t gtpcdr_handle;
static dissector_table_t bssap_pdu_type_table=NULL;

static int decode_gtp_cause         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_imsi          (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rai           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_tlli          (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ptmsi         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_qos_gprs            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_reorder       (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_auth_tri            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_map_cause           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ptmsi_sig           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ms_valid            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_recovery            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_sel_mode            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_16            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_17            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_18            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_19            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_nsapi         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ranap_cause   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rab_cntxt           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rp_sms        (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rp            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_pkt_flow_id   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_chrg_char           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_trace_ref           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_trace_type    (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ms_reason           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_tr_comm       (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_chrg_id       (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_user_addr           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mm_cntxt            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_pdp_cntxt           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_apn           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_gsn_addr            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_proto_conf    (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_msisdn        (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_qos_umts            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_auth_qui            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_tft           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_target_id           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_utran_cont    (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rab_setup           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_hdr_list            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_trigger_id    (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_omc_id        (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);

static int decode_gtp_ran_tr_cont   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_pdp_cont_prio (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_add_rab_setup_inf   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ssgn_no             (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_common_flgs         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_apn_res             (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ra_prio_lcs         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rat_type                  (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_usr_loc_inf         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ms_time_zone        (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_imeisv              (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_camel_chg_inf_con   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_ue_ctx         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_tmgi                      (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rim_ra              (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_prot_conf_opt  (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_sa                   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_src_rnc_pdp_ctx_inf (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_add_trs_inf               (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_hop_count                 (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_sel_plmn_id         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_ses_id         (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_2g_3g_ind      (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_enh_nsapi                 (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_ses_dur        (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_add_mbms_trs_inf    (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_ses_id_rep_no(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_mbms_time_to_data_tr(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_ps_ho_req_ctx (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_bss_cont            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_cell_id       (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_pdu_no        (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_bssgp_cause   (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);

static int decode_gtp_chrg_addr           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_rel_pack            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_can_pack            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_data_req            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_data_resp           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_node_addr           (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_priv_ext            (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);
static int decode_gtp_unknown       (tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree);

typedef struct _gtp_opt {
      int   optcode;
      int  (*decode)(tvbuff_t  *, int, packet_info *, proto_tree *);
} gtp_opt_t;

static const gtp_opt_t gtpopt[] = {
      { GTP_EXT_CAUSE,                    decode_gtp_cause },
      { GTP_EXT_IMSI,                           decode_gtp_imsi },
      { GTP_EXT_RAI,                            decode_gtp_rai },
      { GTP_EXT_TLLI,                           decode_gtp_tlli },
      { GTP_EXT_PTMSI,                    decode_gtp_ptmsi },
      { GTP_EXT_QOS_GPRS,                       decode_gtp_qos_gprs },
      { GTP_EXT_REORDER,                        decode_gtp_reorder },
      { GTP_EXT_AUTH_TRI,                       decode_gtp_auth_tri },
      { GTP_EXT_MAP_CAUSE,                decode_gtp_map_cause },
      { GTP_EXT_PTMSI_SIG,                decode_gtp_ptmsi_sig },
      { GTP_EXT_MS_VALID,                       decode_gtp_ms_valid },
      { GTP_EXT_RECOVER,                        decode_gtp_recovery },
      { GTP_EXT_SEL_MODE,                       decode_gtp_sel_mode },
      { GTP_EXT_16,                             decode_gtp_16 },
      { GTP_EXT_17,                             decode_gtp_17 },
      { GTP_EXT_18,                             decode_gtp_18 },
      { GTP_EXT_19,                             decode_gtp_19 },
      { GTP_EXT_NSAPI,                    decode_gtp_nsapi },
      { GTP_EXT_RANAP_CAUSE,              decode_gtp_ranap_cause },
      { GTP_EXT_RAB_CNTXT,                decode_gtp_rab_cntxt },
      { GTP_EXT_RP_SMS,                   decode_gtp_rp_sms },
      { GTP_EXT_RP,                             decode_gtp_rp },
      { GTP_EXT_PKT_FLOW_ID,              decode_gtp_pkt_flow_id },
      { GTP_EXT_CHRG_CHAR,                decode_gtp_chrg_char },
      { GTP_EXT_TRACE_REF,                decode_gtp_trace_ref },
      { GTP_EXT_TRACE_TYPE,               decode_gtp_trace_type },
      { GTPv1_EXT_MS_REASON,              decode_gtp_ms_reason },
      { GTP_EXT_TR_COMM,                        decode_gtp_tr_comm },
      { GTP_EXT_CHRG_ID,                        decode_gtp_chrg_id },
      { GTP_EXT_USER_ADDR,                decode_gtp_user_addr },
      { GTP_EXT_MM_CNTXT,                       decode_gtp_mm_cntxt },
      { GTP_EXT_PDP_CNTXT,                decode_gtp_pdp_cntxt },
      { GTP_EXT_APN,                            decode_gtp_apn },
      { GTP_EXT_PROTO_CONF,               decode_gtp_proto_conf },
      { GTP_EXT_GSN_ADDR,                       decode_gtp_gsn_addr },
      { GTP_EXT_MSISDN,                   decode_gtp_msisdn },
      { GTP_EXT_QOS_UMTS,                       decode_gtp_qos_umts },                    /* 3G */
      { GTP_EXT_AUTH_QUI,                       decode_gtp_auth_qui },                    /* 3G */
      { GTP_EXT_TFT,                            decode_gtp_tft },                         /* 3G */
      { GTP_EXT_TARGET_ID,                decode_gtp_target_id },                   /* 3G */
      { GTP_EXT_UTRAN_CONT,               decode_gtp_utran_cont },                  /* 3G */
      { GTP_EXT_RAB_SETUP,                decode_gtp_rab_setup },                   /* 3G */
      { GTP_EXT_HDR_LIST,                       decode_gtp_hdr_list },                    /* 3G */
      { GTP_EXT_TRIGGER_ID,               decode_gtp_trigger_id },                  /* 3G */
      { GTP_EXT_OMC_ID,                   decode_gtp_omc_id },                      /* 3G */
      /* TS 29 060 V6.11.0 */
      { GTP_EXT_RAN_TR_CONT,              decode_gtp_ran_tr_cont },                       /* 7.7.43 */
      { GTP_EXT_PDP_CONT_PRIO,            decode_gtp_pdp_cont_prio },                     /* 7.7.45 */
      { GTP_EXT_ADD_RAB_SETUP_INF,  decode_gtp_add_rab_setup_inf },                 /* 7.7.45A */
      { GTP_EXT_SSGN_NO,                        decode_gtp_ssgn_no },                           /* 7.7.47 */
      { GTP_EXT_COMMON_FLGS,              decode_gtp_common_flgs },                       /* 7.7.48 */
      { GTP_EXT_APN_RES,                        decode_gtp_apn_res },                           /* 3G */
      { GTP_EXT_RA_PRIO_LCS,              decode_gtp_ra_prio_lcs },                       /* 7.7.25B */
      { GTP_EXT_RAT_TYPE,                       decode_gtp_rat_type },                          /* 3G */
      { GTP_EXT_USR_LOC_INF,              decode_gtp_usr_loc_inf},                        /* 7.7.51 */
      { GTP_EXT_MS_TIME_ZONE,             decode_gtp_ms_time_zone},                       /* 7.7.52 */
      { GTP_EXT_IMEISV,                   decode_gtp_imeisv },                            /* 3G 7.7.53*/
      { GTP_EXT_CAMEL_CHG_INF_CON,  decode_gtp_camel_chg_inf_con },                 /* 7.7.54 */
      { GTP_EXT_MBMS_UE_CTX,              decode_gtp_mbms_ue_ctx },                       /* 7.7.55 */
      { GTP_EXT_TMGI,                           decode_gtp_tmgi },                                    /* 7.7.56 */
      { GTP_EXT_RIM_RA,                   decode_gtp_rim_ra },                            /* 7.7.57 */
      { GTP_EXT_MBMS_PROT_CONF_OPT, decode_gtp_mbms_prot_conf_opt },          /* 7.7.58 */
      { GTP_EXT_MBMS_SA,                        decode_gtp_mbms_sa },                           /* 7.7.60 */
      { GTP_EXT_SRC_RNC_PDP_CTX_INF,      decode_gtp_src_rnc_pdp_ctx_inf },         /* 7.7.61 */
      { GTP_EXT_ADD_TRS_INF,              decode_gtp_add_trs_inf },                       /* 7.7.62 */
      { GTP_EXT_HOP_COUNT,                decode_gtp_hop_count },                         /* 7.7.63 */
      { GTP_EXT_SEL_PLMN_ID,              decode_gtp_sel_plmn_id },                       /* 7.7.64 */
      { GTP_EXT_MBMS_SES_ID,              decode_gtp_mbms_ses_id },                       /* 7.7.65 */
      { GTP_EXT_MBMS_2G_3G_IND,           decode_gtp_mbms_2g_3g_ind },              /* 7.7.66 */
      { GTP_EXT_ENH_NSAPI,                decode_gtp_enh_nsapi },                         /* 7.7.67 */
      { GTP_EXT_MBMS_SES_DUR,             decode_gtp_mbms_ses_dur },                      /* 7.7.59 */
      { GTP_EXT_ADD_MBMS_TRS_INF,         decode_gtp_add_mbms_trs_inf },                  /* 7.7.68 */
      { GTP_EXT_MBMS_SES_ID_REP_NO, decode_gtp_mbms_ses_id_rep_no },          /* 7.7.69 */
      { GTP_EXT_MBMS_TIME_TO_DATA_TR,     decode_gtp_mbms_time_to_data_tr },        /* 7.7.70 */
      { GTP_EXT_PS_HO_REQ_CTX,            decode_gtp_ps_ho_req_ctx },                     /* 7.7.71 */
      { GTP_EXT_BSS_CONT,                       decode_gtp_bss_cont },                          /* 7.7.72 */
      { GTP_EXT_CELL_ID,                        decode_gtp_cell_id },                           /* 7.7.73 */
      { GTP_EXT_PDU_NO,                   decode_gtp_pdu_no },                            /* 7.7.74 */
      { GTP_EXT_BSSGP_CAUSE,              decode_gtp_bssgp_cause },                       /* 7.7.75 */

      { GTP_EXT_REL_PACK,           decode_gtp_rel_pack },                    /* charging */
      { GTP_EXT_CAN_PACK,           decode_gtp_can_pack },                    /* charging */
      { GTP_EXT_CHRG_ADDR,    decode_gtp_chrg_addr },
      { GTP_EXT_DATA_REQ,           decode_gtp_data_req },                    /* charging */
      { GTP_EXT_DATA_RESP,    decode_gtp_data_resp },                   /* charging */
      { GTP_EXT_NODE_ADDR,    decode_gtp_node_addr },
      { GTP_EXT_PRIV_EXT,           decode_gtp_priv_ext },
      { 0,              decode_gtp_unknown }
};

struct _gtp_hdr {
      guint8            flags;
      guint8            message;
      guint16           length;
};

static      guint8            gtp_version = 0;
static      const char  *yesno[] = { "no", "yes" };

static void
col_append_str_gtp(column_info *cinfo, gint el, const gchar *proto_name) {

      int   i;
      int   max_len;
      gchar _tmp[COL_MAX_LEN];

      max_len = COL_MAX_LEN;

      for (i = 0; i < cinfo->num_cols; i++) {
            if (cinfo->fmt_matx[i][el]) {
                  if (cinfo->col_data[i] != cinfo->col_buf[i]) {

                        strncpy(cinfo->col_buf[i], cinfo->col_data[i], max_len);
                        cinfo->col_buf[i][max_len - 1] = '\0';
                        }

                  _tmp[0] = '\0';
                  strcat(_tmp, proto_name);
                  strcat(_tmp, " <");
                  strcat(_tmp, cinfo->col_buf[i]);
                  strcat(_tmp, ">");
                  cinfo->col_buf[i][0] = '\0';
                  strcat(cinfo->col_buf[i], _tmp);
                  cinfo->col_data[i] = cinfo->col_buf[i];
            }
      }
}

static gchar *
id_to_str(const guint8 *ad) {

      static gchar      str[17] = "                ";
      guint8            bits8to5, bits4to1;
      int         i, j = 0;
      static const      gchar hex_digits[10] = "0123456789";

      for (i = 0; i < 8; i++) {
            bits8to5 = (ad[i] >> 4) & 0x0F;
            bits4to1 = ad[i] & 0x0F;
            if (bits4to1 < 0xA)
                  str[j++] = hex_digits[bits4to1];
            if (bits8to5 < 0xA)
                  str[j++] = hex_digits[bits8to5];
      }
      str[j] = '\0';
      return str;
}

static gchar *
imsi_to_str(const guint8 *ad) {

      static gchar      str[17] = "                ";
      int         i, j = 0;

      for (i = 0; i < 8; i++) {
            if ((ad[i] & 0x0F) <= 9) str[j++] = (ad[i] & 0x0F) + 0x30;
            if (((ad[i] >> 4) & 0x0F) <= 9) str[j++] = ((ad[i] >> 4) & 0x0F) + 0x30;
      }
      str[j] = '\0';

      return str;
}

static gchar *
msisdn_to_str(const guint8 *ad, int len) {

      static gchar      str[18] = "+                ";
      guint8            bits8to5, bits4to1;
      int         i, j = 1;
      static const      gchar hex_digits[10] = "0123456789";

      for (i = 1; i < len && i < 9; i++) {
            bits8to5 = (ad[i] >> 4) & 0x0F;
            bits4to1 = ad[i] & 0x0F;
            if (bits4to1 < 0xA)
                  str[j++] = hex_digits[bits4to1];
            if (bits8to5 < 0xA)
                  str[j++] = hex_digits[bits8to5];
      }
      str[j] = '\0';

      return str;
}

/* Next definitions and function check_field_presence checks if given field
 * in GTP packet is compliant with ETSI
 */
typedef struct _header {
      guint8            code;
      guint8            presence;
} ext_header;

typedef struct _message {
      guint8            code;
      ext_header  fields[32];
} _gtp_mess_items;

/* ---------------------
 * GPRS messages
 * ---------------------*/
static _gtp_mess_items gprs_mess_items[] = {

{
      GTP_MSG_ECHO_REQ, {
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_ECHO_RESP, {
            { GTP_EXT_RECOVER,      GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_VER_NOT_SUPP, {
            { 0,              0 }
      }
},
{
      GTP_MSG_NODE_ALIVE_REQ, {
            { GTP_EXT_NODE_ADDR,    GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_NODE_ALIVE_RESP, {
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_REDIR_REQ, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_NODE_ADDR,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_REDIR_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_CREATE_PDP_REQ, {
            { GTP_EXT_QOS_GPRS,     GTP_MANDATORY },
            { GTP_EXT_RECOVER,            GTP_OPTIONAL },
            { GTP_EXT_SEL_MODE,     GTP_MANDATORY },
            { GTP_EXT_FLOW_LABEL,   GTP_MANDATORY },
            { GTP_EXT_FLOW_SIG,           GTP_MANDATORY },
            { GTP_EXT_MSISDN,       GTP_MANDATORY },
            { GTP_EXT_USER_ADDR,    GTP_MANDATORY },
            { GTP_EXT_APN,                GTP_MANDATORY },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_CREATE_PDP_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_QOS_GPRS,     GTP_CONDITIONAL },
            { GTP_EXT_REORDER,      GTP_CONDITIONAL },
            { GTP_EXT_RECOVER,      GTP_OPTIONAL },
            { GTP_EXT_FLOW_LABEL,   GTP_CONDITIONAL },
            { GTP_EXT_FLOW_SIG,     GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ID,      GTP_CONDITIONAL },
            { GTP_EXT_USER_ADDR,    GTP_CONDITIONAL },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_UPDATE_PDP_REQ, {
            { GTP_EXT_QOS_GPRS,     GTP_MANDATORY },
            { GTP_EXT_RECOVER,      GTP_OPTIONAL },
            { GTP_EXT_FLOW_LABEL,   GTP_MANDATORY },
            { GTP_EXT_FLOW_SIG,     GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,     GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,     GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 },
      }
},
{
      GTP_MSG_UPDATE_PDP_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_QOS_GPRS,     GTP_CONDITIONAL },
            { GTP_EXT_RECOVER,      GTP_OPTIONAL },
            { GTP_EXT_FLOW_LABEL,   GTP_CONDITIONAL },
            { GTP_EXT_FLOW_SIG,     GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ID,      GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DELETE_PDP_REQ, {
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DELETE_PDP_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 },
      }
},
{
      GTP_MSG_CREATE_AA_PDP_REQ, {
            { GTP_EXT_QOS_GPRS,     GTP_MANDATORY },
            { GTP_EXT_RECOVER,      GTP_OPTIONAL },
            { GTP_EXT_SEL_MODE,     GTP_MANDATORY },
            { GTP_EXT_FLOW_LABEL,   GTP_MANDATORY },
            { GTP_EXT_FLOW_SIG,     GTP_MANDATORY },
            { GTP_EXT_USER_ADDR,    GTP_MANDATORY },
            { GTP_EXT_APN,          GTP_MANDATORY },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,     GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_CREATE_AA_PDP_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_QOS_GPRS,     GTP_CONDITIONAL },
            { GTP_EXT_REORDER,      GTP_CONDITIONAL },
            { GTP_EXT_RECOVER,      GTP_OPTIONAL },
            { GTP_EXT_FLOW_LABEL,   GTP_CONDITIONAL },
            { GTP_EXT_FLOW_SIG,     GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ID,      GTP_CONDITIONAL },
            { GTP_EXT_USER_ADDR,    GTP_CONDITIONAL },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DELETE_AA_PDP_REQ, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DELETE_AA_PDP_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_ERR_IND, {
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_REQ, {
            { GTP_EXT_USER_ADDR,    GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_REJ_REQ, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_USER_ADDR,    GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_REJ_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SEND_ROUT_INFO_REQ, {
            { GTP_EXT_IMSI,         GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SEND_ROUT_INFO_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_MAP_CAUSE,    GTP_OPTIONAL },
            { GTP_EXT_MS_REASON,    GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FAIL_REP_REQ, {
            { GTP_EXT_IMSI,         GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FAIL_REP_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_MAP_CAUSE,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_MS_PRESENT_REQ, {
            { GTP_EXT_IMSI,         GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,     GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_MS_PRESENT_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_IDENT_REQ, {
            { GTP_EXT_RAI,          GTP_MANDATORY },
            { GTP_EXT_PTMSI,  GTP_MANDATORY },
            { GTP_EXT_PTMSI_SIG,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_IDENT_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_IMSI,         GTP_CONDITIONAL },
            { GTP_EXT_AUTH_TRI,     GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SGSN_CNTXT_REQ, {
            { GTP_EXT_IMSI,         GTP_CONDITIONAL },
            { GTP_EXT_RAI,          GTP_MANDATORY },
            { GTP_EXT_TLLI,         GTP_MANDATORY },
            { GTP_EXT_PTMSI_SIG,    GTP_OPTIONAL },
            { GTP_EXT_MS_VALID,     GTP_OPTIONAL },
            { GTP_EXT_FLOW_SIG,     GTP_MANDATORY },
            { 0,              0 }
      }
},
{
      GTP_MSG_SGSN_CNTXT_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_IMSI,         GTP_CONDITIONAL },
            { GTP_EXT_FLOW_SIG,     GTP_CONDITIONAL },
            { GTP_EXT_MM_CNTXT,     GTP_CONDITIONAL },
            { GTP_EXT_PDP_CNTXT,    GTP_CONDITIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SGSN_CNTXT_ACK, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_FLOW_II,      GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,     GTP_CONDITIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DATA_TRANSF_REQ, {
            { GTP_EXT_TR_COMM,      GTP_MANDATORY },
            { GTP_EXT_DATA_REQ,     GTP_CONDITIONAL },
            { GTP_EXT_REL_PACK,     GTP_CONDITIONAL },
            { GTP_EXT_CAN_PACK,     GTP_CONDITIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DATA_TRANSF_RESP, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_DATA_RESP,    GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      0, {
            { 0,              0 }
      }
}
};

/* -----------------------------
 * UMTS messages
 * -----------------------------*/
static _gtp_mess_items umts_mess_items[] = {
      /* 7.2 Path Management Messages */
{
      GTP_MSG_ECHO_REQ, {
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_ECHO_RESP, {
            { GTP_EXT_RECOVER,      GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_VER_NOT_SUPP, {
            { 0,              0 }
      }
},
{
      GTP_MSG_SUPP_EXT_HDR, {
            { GTP_EXT_HDR_LIST,     GTP_MANDATORY },
            { 0,              0 }
      }
},
      /* ??? */
{
      GTP_MSG_NODE_ALIVE_REQ, {
            { GTP_EXT_NODE_ADDR,    GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_NODE_ALIVE_RESP, {
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_REDIR_REQ, {
            { GTP_EXT_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_NODE_ADDR,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,     GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_REDIR_REQ, {
            { 0,              0 }
      }
},
      /* 7.3 Tunnel Management Messages */
{
      GTP_MSG_CREATE_PDP_REQ, {
            { GTP_EXT_IMSI,               GTP_CONDITIONAL },
                  /* RAI is in TS 29.060 V6.11.0 */
            { GTP_EXT_RAI,                GTP_OPTIONAL },         /* Routeing Area Identity (RAI) Optional 7.7.3 */
            { GTP_EXT_RECOVER,            GTP_OPTIONAL },
            { GTP_EXT_SEL_MODE,     GTP_CONDITIONAL },
            { GTP_EXT_TEID,               GTP_MANDATORY },
            { GTP_EXT_TEID_CP,            GTP_CONDITIONAL },
            { GTP_EXT_NSAPI,        GTP_MANDATORY },
            { GTP_EXT_NSAPI,        GTP_CONDITIONAL },
            { GTP_EXT_CHRG_CHAR,    GTP_OPTIONAL },
            { GTP_EXT_TRACE_REF,    GTP_OPTIONAL },
            { GTP_EXT_TRACE_TYPE,   GTP_OPTIONAL },
            { GTP_EXT_USER_ADDR,    GTP_CONDITIONAL },
            { GTP_EXT_APN,                GTP_CONDITIONAL },
            { GTP_EXT_PROTO_CONF,   GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_MSISDN,       GTP_CONDITIONAL },
            { GTP_EXT_QOS_UMTS,           GTP_MANDATORY },
            { GTP_EXT_TFT,                GTP_CONDITIONAL },
            { GTP_EXT_TRIGGER_ID,   GTP_OPTIONAL },
            { GTP_EXT_OMC_ID,       GTP_OPTIONAL },
            /* TS 29.060 V6.11.0 */
            { GTP_EXT_APN_RES,            GTP_OPTIONAL },
            { GTP_EXT_RAT_TYPE,           GTP_OPTIONAL },
            { GTP_EXT_USR_LOC_INF,  GTP_OPTIONAL },
            { GTP_EXT_MS_TIME_ZONE, GTP_OPTIONAL },
            { GTP_EXT_IMEISV,       GTP_OPTIONAL },
            { GTP_EXT_CAMEL_CHG_INF_CON, GTP_OPTIONAL },
            { GTP_EXT_ADD_TRS_INF,  GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_CREATE_PDP_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_REORDER,            GTP_CONDITIONAL },
            { GTP_EXT_RECOVER,            GTP_OPTIONAL },
            { GTP_EXT_TEID,               GTP_CONDITIONAL },
            { GTP_EXT_TEID_CP,            GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ID,            GTP_CONDITIONAL },
            { GTP_EXT_USER_ADDR,    GTP_CONDITIONAL },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_QOS_UMTS,           GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },
            /* TS 29.060 V6.11.0 */
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },         /* Alternative Charging Gateway Address Optional 7.7.44 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },   
            { GTP_EXT_COMMON_FLGS,  GTP_OPTIONAL },         /* Common Flags Optional 7.7.48 */
            { GTP_EXT_APN_RES,            GTP_OPTIONAL },         /* APN Restriction Optional 7.7.49 */
            { 0,              0 }
      }
},
{     /* checked, SGSN -> GGSN */
      GTP_MSG_UPDATE_PDP_REQ, {
            { GTP_EXT_IMSI,               GTP_CONDITIONAL },
            { GTP_EXT_RAI,                GTP_OPTIONAL },         /* Routeing Area Identity (RAI) Optional 7.7.3 */
            { GTP_EXT_RECOVER,            GTP_OPTIONAL },
            { GTP_EXT_TEID,               GTP_MANDATORY },
            { GTP_EXT_TEID_CP,            GTP_CONDITIONAL },
            { GTP_EXT_NSAPI,        GTP_MANDATORY },
            { GTP_EXT_TRACE_REF,    GTP_OPTIONAL },
            { GTP_EXT_TRACE_TYPE,   GTP_OPTIONAL },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },         /* Protocol Configuration Options Optional 7.7.31 */
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },  /* SGSN Address for Control Plane Mandatory GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },  /* SGSN Address for User Traffic Mandatory GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },         /* Alternative SGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },         /* Alternative SGSN Address for User Traffic Conditional GSN Address 7.7.32 */
            { GTP_EXT_QOS_UMTS,           GTP_MANDATORY },
            { GTP_EXT_TFT,                GTP_OPTIONAL },
            { GTP_EXT_TRIGGER_ID,   GTP_OPTIONAL },
            { GTP_EXT_OMC_ID,       GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { GTP_EXT_RAT_TYPE,           GTP_OPTIONAL },         /* RAT Type Optional 7.7.50 */
            { GTP_EXT_USR_LOC_INF,  GTP_OPTIONAL },         /* User Location Information Optional 7.7.51 */
            { GTP_EXT_MS_TIME_ZONE, GTP_OPTIONAL },         /* MS Time Zone Optional 7.7.52 */
            { GTP_EXT_ADD_TRS_INF,  GTP_OPTIONAL },         /* Additonal Trace Info Optional 7.7.62 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{     /* checked, GGSN -> SGSN */
      GTP_MSG_UPDATE_PDP_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_RECOVER,            GTP_OPTIONAL },
            { GTP_EXT_TEID,               GTP_CONDITIONAL },
            { GTP_EXT_TEID_CP,            GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ID,            GTP_CONDITIONAL },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },         /* Protocol Configuration Options Optional 7.7.31 */
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },         /* Alternative SGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },         /* Alternative SGSN Address for User Traffic Conditional GSN Address 7.7.32 */
            { GTP_EXT_QOS_UMTS,           GTP_CONDITIONAL },
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },
            { GTP_EXT_CHRG_ADDR,    GTP_OPTIONAL },         /* Alternative Charging Gateway Address Optional 7.7.44 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { GTP_EXT_COMMON_FLGS,  GTP_OPTIONAL },         /* Common Flags Optional 7.7.48 */
            { GTP_EXT_APN_RES,            GTP_OPTIONAL },         /* APN Restriction Optional 7.7.49 */
            { 0,              0 }
      }
},
{
      GTP_MSG_DELETE_PDP_REQ, {
            { GTP_EXT_TEAR_IND,           GTP_CONDITIONAL },
            { GTP_EXT_NSAPI,        GTP_MANDATORY },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },         /* Protocol Configuration Options Optional 7.7.31 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_DELETE_PDP_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },         /* Protocol Configuration Options Optional 7.7.31 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_ERR_IND, {
            { GTP_EXT_TEID,               GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },  /* GSN Address Mandatory 7.7.32 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_REQ, {
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_TEID_CP,            GTP_MANDATORY },
            { GTP_EXT_USER_ADDR,    GTP_MANDATORY },
            { GTP_EXT_APN,                GTP_MANDATORY },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },         /* Protocol Configuration Options Optional 7.7.31 */
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_REJ_REQ, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_TEID_CP,            GTP_MANDATORY },
            { GTP_EXT_USER_ADDR,    GTP_MANDATORY },
            { GTP_EXT_APN,                GTP_MANDATORY },
            { GTP_EXT_PROTO_CONF,   GTP_OPTIONAL },         /* Protocol Configuration Options Optional 7.7.31 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_PDU_NOTIFY_REJ_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
      /* 7.4 Location Management Messages */
{
      GTP_MSG_SEND_ROUT_INFO_REQ, {
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SEND_ROUT_INFO_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_MAP_CAUSE,    GTP_OPTIONAL },
            { GTPv1_EXT_MS_REASON,  GTP_OPTIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FAIL_REP_REQ, {
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FAIL_REP_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_MAP_CAUSE,    GTP_OPTIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_MS_PRESENT_REQ, {
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_MS_PRESENT_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
      /* 7.5 Mobility Management Messages */
{
      GTP_MSG_IDENT_REQ, {
            { GTP_EXT_RAI,                GTP_MANDATORY },
            { GTP_EXT_PTMSI,        GTP_MANDATORY },
            { GTP_EXT_PTMSI_SIG,    GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },         /* SGSN Address for Control Plane Optional 7.7.32 */
            { GTP_EXT_HOP_COUNT,    GTP_OPTIONAL },         /* Hop Counter Optional 7.7.63 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_IDENT_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_IMSI,               GTP_CONDITIONAL },
            { GTP_EXT_AUTH_TRI,           GTP_CONDITIONAL },
            { GTP_EXT_AUTH_QUI,           GTP_CONDITIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SGSN_CNTXT_REQ, {
            { GTP_EXT_IMSI,               GTP_CONDITIONAL },
            { GTP_EXT_RAI,                GTP_MANDATORY },
            { GTP_EXT_TLLI,               GTP_CONDITIONAL },
            { GTP_EXT_PTMSI,        GTP_CONDITIONAL },
            { GTP_EXT_PTMSI_SIG,    GTP_CONDITIONAL },
            { GTP_EXT_MS_VALID,           GTP_OPTIONAL },
            { GTP_EXT_TEID_CP,            GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_GSN_ADDR,           GTP_OPTIONAL },         /* Alternative SGSN Address for Control Plane Optional 7.7.32 */
            { GTP_EXT_SSGN_NO,            GTP_OPTIONAL },         /* SGSN Number Optional 7.7.47 */
            { GTP_EXT_HOP_COUNT,    GTP_OPTIONAL },         /* Hop Counter Optional 7.7.63 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SGSN_CNTXT_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_IMSI,               GTP_CONDITIONAL },
            { GTP_EXT_TEID_CP,            GTP_CONDITIONAL },
            { GTP_EXT_RAB_CNTXT,    GTP_CONDITIONAL },      /* RAB Context Conditional 7.7.19 */
            { GTP_EXT_RP_SMS,       GTP_OPTIONAL },
            { GTP_EXT_RP,                 GTP_OPTIONAL },
            { GTP_EXT_PKT_FLOW_ID,  GTP_OPTIONAL },
            { GTP_EXT_CHRG_CHAR,    GTP_OPTIONAL },         /* CharingCharacteristics Optional 7.7.23 */
            { GTP_EXT_RA_PRIO_LCS,  GTP_OPTIONAL },         /* Radio Priority LCS Optional 7.7.25B */
            { GTP_EXT_MM_CNTXT,           GTP_CONDITIONAL },
            { GTP_EXT_PDP_CNTXT,    GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_PDP_CONT_PRIO,GTP_OPTIONAL },         /* PDP Context Prioritization Optional 7.7.45 */
            { GTP_EXT_MBMS_UE_CTX,  GTP_OPTIONAL },         /* MBMS UE Context Optional 7.7.55 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_SGSN_CNTXT_ACK, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_TEID_II,            GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FORW_RELOC_REQ, {
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_TEID_CP,            GTP_MANDATORY },
            { GTP_EXT_RANAP_CAUSE,  GTP_MANDATORY },
            { GTP_EXT_CHRG_CHAR,    GTP_OPTIONAL },         /* CharingCharacteristics Optional 7.7.23 */
            { GTP_EXT_MM_CNTXT,           GTP_MANDATORY },
            { GTP_EXT_PDP_CNTXT,    GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_MANDATORY },
            { GTP_EXT_TARGET_ID,    GTP_MANDATORY },
            { GTP_EXT_UTRAN_CONT,   GTP_MANDATORY },
            { GTP_EXT_PDP_CONT_PRIO,GTP_OPTIONAL },         /* PDP Context Prioritization Optional 7.7.45 */
            { GTP_EXT_MBMS_UE_CTX,  GTP_OPTIONAL },         /* MBMS UE Context Optional 7.7.55 */
            { GTP_EXT_SEL_PLMN_ID,  GTP_OPTIONAL },         /* Selected PLMN ID Optional 7.7.64 */
            { GTP_EXT_PS_HO_REQ_CTX,GTP_OPTIONAL },         /* PS Handover Request Context Optional 7.7.71 */
            { GTP_EXT_BSS_CONT,           GTP_OPTIONAL },         /* BSS Container Optional 7.7.72 */
            { GTP_EXT_CELL_ID,            GTP_OPTIONAL },         /* Cell Identification Optional 7.7.73 */
            { GTP_EXT_BSSGP_CAUSE,  GTP_OPTIONAL },         /* BSSGP Cause Optional 7.7.75 */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { GTP_EXT_SSGN_NO,            GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FORW_RELOC_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_TEID_CP,            GTP_CONDITIONAL },
            { GTP_EXT_TEID_II,            GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Data II Optional 7.7.15 */
            { GTP_EXT_RANAP_CAUSE,  GTP_CONDITIONAL },
            { GTP_EXT_GSN_ADDR,           GTP_CONDITIONAL },
            { GTP_EXT_UTRAN_CONT,   GTP_OPTIONAL },
            { GTP_EXT_RAB_SETUP,    GTP_CONDITIONAL },
            { GTP_EXT_ADD_RAB_SETUP_INF,  GTP_CONDITIONAL },      /* Additional RAB Setup Information Conditional 7.7.45A */
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FORW_RELOC_COMP, {
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_RELOC_CANCEL_REQ, {
            { GTP_EXT_IMSI,               GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_RELOC_CANCEL_RESP, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FORW_RELOC_ACK, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FORW_SRNS_CNTXT_ACK, {
            { GTP_EXT_CAUSE,        GTP_MANDATORY },
            { GTP_EXT_PRIV_EXT,           GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
      GTP_MSG_FORW_SRNS_CNTXT, {
            { GTP_EXT_RAB_CNTXT,                GTP_MANDATORY },
            { GTP_EXT_SRC_RNC_PDP_CTX_INF,      GTP_OPTIONAL },         /* Source RNC PDCP context info Optional 7.7.61 */
            { GTP_EXT_PDU_NO,                   GTP_OPTIONAL },         /* PDU Numbers Optional 7.7.74 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},

/*    7.5.14 RAN Information Management Messages */
{
            GTP_MSG_RAN_INFO_RELAY, {
            { GTP_EXT_RAN_TR_CONT,              GTP_MANDATORY },  /* RAN Transparent Container Mandatory 7.7.43 */
            { GTP_EXT_RIM_RA,                   GTP_OPTIONAL },         /* RIM Routing Address Optional 7.7.57 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
/* 7.5A MBMS Messages 
 * 7.5A.1 UE Specific MBMS Messages
 */
{
            GTP_MBMS_NOTIFY_REQ, {
            { GTP_EXT_IMSI,                           GTP_MANDATORY },  /* IMSI Mandatory 7.7.2 */
            { GTP_EXT_TEID_CP,                        GTP_MANDATORY },  /* Tunnel Endpoint Identifier Control Plane Mandatory 7.7.14 */
            { GTP_EXT_NSAPI,                    GTP_MANDATORY },  /* NSAPI Mandatory 7.7.17 */
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_GSN_ADDR,                       GTP_MANDATORY },  /* GGSN Address for Control Plane Mandatory 7.7.32 */
            { GTP_EXT_MBMS_PROT_CONF_OPT, GTP_OPTIONAL },         /* MBMS Protocol Configuration Options Optional 7.7.58 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_NOTIFY_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_MBMS_NOTIFY_REJ_REQ, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_TEID_CP,                        GTP_MANDATORY },  /* Tunnel Endpoint Identifier Control Plane Mandatory 7.7.14 */
            { GTP_EXT_NSAPI,                    GTP_MANDATORY },  /* NSAPI Mandatory 7.7.17 */
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_MBMS_NOTIFY_REJ_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_CREATE_MBMS_CNTXT_REQ, {
            { GTP_EXT_IMSI,                           GTP_CONDITIONAL },      /* IMSI Conditional 7.7.2 */
            { GTP_EXT_RAI,                            GTP_MANDATORY },  /* Routeing Area Identity (RAI) Mandatory 7.7.3 */
            { GTP_EXT_RECOVER,                        GTP_OPTIONAL },         /* Recovery Optional 7.7.11 */
            { GTP_EXT_SEL_MODE,                       GTP_CONDITIONAL },      /* Selection mode Conditional 7.7.12 */
            { GTP_EXT_TEID_CP,                        GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_TRACE_REF,                GTP_OPTIONAL },         /* Trace Reference Optional 7.7.24 */
            { GTP_EXT_TRACE_TYPE,               GTP_OPTIONAL },         /* Trace Type Optional 7.7.25 */
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_GSN_ADDR,                       GTP_MANDATORY },  /* SGSN Address for signalling Mandatory GSN Address 7.7.32 */
            { GTP_EXT_MSISDN,                   GTP_CONDITIONAL },      /* MSISDN Conditional 7.7.33 */
            { GTP_EXT_TRIGGER_ID,               GTP_OPTIONAL },         /* Trigger Id Optional 7.7.41 */
            { GTP_EXT_OMC_ID,                   GTP_OPTIONAL },         /* OMC Identity Optional 7.7.42 */
            { GTP_EXT_RAT_TYPE,                       GTP_OPTIONAL },         /* RAT Type Optional 7.7.50 */
            { GTP_EXT_USR_LOC_INF,              GTP_OPTIONAL },         /* User Location Information Optional 7.7.51 */
            { GTP_EXT_MS_TIME_ZONE,             GTP_OPTIONAL },         /* MS Time Zone Optional 7.7.52 */
            { GTP_EXT_IMEISV,                   GTP_OPTIONAL },         /* IMEI(SV) Optional 7.7.53 */
            { GTP_EXT_MBMS_PROT_CONF_OPT, GTP_OPTIONAL },         /* MBMS Protocol Configuration Options Optional 7.7.58 */
            { GTP_EXT_ADD_TRS_INF,              GTP_OPTIONAL },         /* Additonal Trace Info Optional 7.7.62 */
            { GTP_EXT_ENH_NSAPI,                GTP_MANDATORY },  /* Enhanced NSAPI Mandatory 7.7.67 */
            { GTP_EXT_ADD_MBMS_TRS_INF,         GTP_OPTIONAL },         /* Additional MBMS Trace Info Optional 7.7.68 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_CREATE_MBMS_CNTXT_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_RECOVER,                        GTP_OPTIONAL },         /* Recovery Optional 7.7.11 */
            { GTP_EXT_TEID_CP,                        GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_CHRG_ID,                        GTP_CONDITIONAL },      /* Charging ID Conditional 7.7.26 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* GGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* Alternative GGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_CHRG_ADDR,                GTP_OPTIONAL },         /* Charging Gateway Address Optional 7.7.44 */
            { GTP_EXT_CHRG_ADDR,                GTP_OPTIONAL },         /* Alternative Charging Gateway Address Optional 7.7.44 */
            { GTP_EXT_MBMS_PROT_CONF_OPT, GTP_OPTIONAL },         /* MBMS Protocol Configuration Options Optional 7.7.58 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_UPD_MBMS_CNTXT_REQ, {
            { GTP_EXT_IMSI,                     GTP_CONDITIONAL },            /* IMSI Conditional 7.7.2 */
            { GTP_EXT_RAI,                            GTP_MANDATORY },  /* Routeing Area Identity (RAI) Mandatory 7.7.3 */
            { GTP_EXT_RECOVER,                        GTP_OPTIONAL },         /* Recovery Optional 7.7.11 */
            { GTP_EXT_TEID_CP,                        GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_TRACE_REF,                GTP_OPTIONAL },         /* Trace Reference Optional 7.7.24 */
            { GTP_EXT_TRACE_TYPE,               GTP_OPTIONAL },         /* Trace Type Optional 7.7.25 */
            { GTP_EXT_GSN_ADDR,                       GTP_MANDATORY },  /* SGSN Address for Control Plane Mandatory GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* Alternative SGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_TRIGGER_ID,               GTP_OPTIONAL },         /* Trigger Id Optional 7.7.41 */
            { GTP_EXT_OMC_ID,                   GTP_OPTIONAL },         /* OMC Identity Optional 7.7.42 */
            { GTP_EXT_RAT_TYPE,                       GTP_OPTIONAL },         /* RAT Type Optional 7.7.50 */
            { GTP_EXT_USR_LOC_INF,              GTP_OPTIONAL },         /* User Location Information Optional 7.7.51 */
            { GTP_EXT_MS_TIME_ZONE,             GTP_OPTIONAL },         /* MS Time Zone Optional 7.7.52 */
            { GTP_EXT_ADD_TRS_INF,              GTP_OPTIONAL },         /* Additional Trace Info Optional 7.7.62 */
            { GTP_EXT_ENH_NSAPI,                GTP_MANDATORY },  /* Enhanced NSAPI Mandatory 7.7.67 */
            { GTP_EXT_ADD_MBMS_TRS_INF,         GTP_OPTIONAL },         /* Additional MBMS Trace Info Optional 7.7.68 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_UPD_MBMS_CNTXT_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_RECOVER,                        GTP_OPTIONAL },         /* Recovery Optional 7.7.11 */
            { GTP_EXT_TEID_CP,                        GTP_MANDATORY },  /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_CHRG_ID,                        GTP_CONDITIONAL },      /* Charging ID Conditional 7.7.26 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* GGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* Alternative GGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_CHRG_ADDR,                GTP_OPTIONAL },         /* Charging Gateway Address Optional 7.7.44 */
            { GTP_EXT_CHRG_ADDR,                GTP_OPTIONAL },         /* Alternative Charging Gateway Address Optional 7.7.44 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_DEL_MBMS_CNTXT_REQ, {
            { GTP_EXT_IMSI,                           GTP_CONDITIONAL },      /* IMSI Conditional 7.7.2 */
            { GTP_EXT_TEID_CP,                        GTP_MANDATORY },  /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_USER_ADDR,                GTP_CONDITIONAL },      /* End User Address Conditional 7.7.27 */
            { GTP_EXT_APN,                            GTP_CONDITIONAL },      /* Access Point Name Conditional 7.7.30 */
            { GTP_EXT_MBMS_PROT_CONF_OPT, GTP_OPTIONAL },         /* MBMS Protocol Configuration Options Optional 7.7.58 */
            { GTP_EXT_ENH_NSAPI,                GTP_MANDATORY },  /* Enhanced NSAPI Conditional 7.7.67 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_DEL_MBMS_CNTXT_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_MBMS_PROT_CONF_OPT, GTP_OPTIONAL },         /* MBMS Protocol Configuration Options Optional 7.7.58 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },
            { 0,              0 }
      }
},
{
            GTP_MBMS_REG_REQ, {
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_REG_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_TMGI,                           GTP_MANDATORY },  /* Temporary Mobile Group Identity (TMGI) Conditional 7.7.56 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_DE_REG_REQ, {
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_DE_REG_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_SES_START_REQ, {
            { GTP_EXT_RECOVER,                        GTP_OPTIONAL },         /* Recovery Optional 7.7.11 */
            { GTP_EXT_TEID_CP,                        GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* GGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_QOS_UMTS,                       GTP_MANDATORY },  /* Quality of Service Profile Mandatory 7.7.34 */
            { GTP_EXT_COMMON_FLGS,              GTP_OPTIONAL },         /* Common Flags Mandatory 7.7.48 */
            { GTP_EXT_TMGI,                           GTP_MANDATORY },  /* Temporary Mobile Group Identity (TMGI) Mandatory 7.7.56 */
            { GTP_EXT_MBMS_SES_DUR,             GTP_MANDATORY },  /* MBMS Session Duration Mandatory 7.7.59 */
            { GTP_EXT_MBMS_SA,                        GTP_MANDATORY },  /* MBMS Service Area Mandatory 7.7.60 */
            { GTP_EXT_MBMS_SES_ID,              GTP_OPTIONAL },         /* MBMS Session Identifier Optional 7.7.65 */
            { GTP_EXT_MBMS_2G_3G_IND,           GTP_MANDATORY },  /* MBMS 2G/3G Indicator Mandatory 7.7.66 */
            { GTP_EXT_MBMS_SES_ID_REP_NO, GTP_OPTIONAL },         /* MBMS Session Identity Repetition Number Optional 7.7.69 */
            { GTP_EXT_MBMS_TIME_TO_DATA_TR,     GTP_MANDATORY },  /* MBMS Time To Data Transfer Mandatory 7.7.70 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_SES_START_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_RECOVER,                        GTP_OPTIONAL },         /* Recovery Optional 7.7.11 */
            { GTP_EXT_TEID,                           GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Data I Conditional 7.7.13 */
            { GTP_EXT_TEID_CP,                        GTP_CONDITIONAL },      /* Tunnel Endpoint Identifier Control Plane Conditional 7.7.14 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* SGSN Address for Control Plane Conditional GSN Address 7.7.32 */
            { GTP_EXT_GSN_ADDR,                       GTP_CONDITIONAL },      /* SGSN Address for user traffic Conditional GSN Address 7.7.32 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_SES_STOP_REQ, {
            { GTP_EXT_USER_ADDR,                GTP_MANDATORY },  /* End User Address Mandatory 7.7.27 */
            { GTP_EXT_APN,                            GTP_MANDATORY },  /* Access Point Name Mandatory 7.7.30 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
            GTP_MBMS_SES_STOP_RES, {
            { GTP_EXT_CAUSE,                    GTP_MANDATORY },  /* Cause Mandatory 7.7.1 */
            { GTP_EXT_PRIV_EXT,                       GTP_OPTIONAL },         /* Private Extension Optional 7.7.46 */
            { 0,              0 }
      }
},
{
      0, {
            { 0,              0 }
      }
}
};

static int
check_field_presence(guint8 message, guint8 field, int *position) {

      guint             i = 0;
      _gtp_mess_items         *mess_items;

      switch(gtp_version) {
            case 0:
                  mess_items = gprs_mess_items;
                  break;
            case 1:
                  mess_items = umts_mess_items;
                  break;
            default:
                  return -2;
      }

      while (mess_items[i].code) {
            if (mess_items[i].code == message) {

                  while (mess_items[i].fields[*position].code) {
                        if (mess_items[i].fields[*position].code == field) {
                              (*position)++;
                              return 0;
                        } else {
                        if (mess_items[i].fields[*position].presence == GTP_MANDATORY) {
                              return mess_items[i].fields[(*position)++].code;
                        } else {
                              (*position)++;
                        }}
                  }
                  return -1;
            }
            i++;
      }

      return -2;
}

/* Decoders of fields in extension headers, each function returns no of bytes from field */

/* GPRS:    9.60 v7.6.0, chapter
 * UMTS:    29.060 v4.0, chapter
 */
static int
decode_gtp_cause(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      cause;

      cause = tvb_get_guint8(tvb, offset+1);

      proto_tree_add_uint(tree, hf_gtp_cause, tvb, offset, 2, cause);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.2
 * UMTS:    29.060 v4.0, chapter 7.7.2
 */
static int
decode_gtp_imsi(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      imsi_val[8];
      gchar *imsi_str;

      tvb_memcpy(tvb, imsi_val, offset+1, 8);
      imsi_str = imsi_to_str (imsi_val);

      proto_tree_add_string (tree, hf_gtp_imsi, tvb, offset, 9, imsi_str);

      return 9;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.3
 * UMTS:    29.060 v4.0, chapter 7.7.3
 */
static int
decode_gtp_rai(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      proto_tree  *ext_tree_rai;
      proto_item  *te;
      guint8            byte[3];
      guint16           mnc, mcc;

      te = proto_tree_add_text(tree, tvb, offset, 1, val_to_str(GTP_EXT_RAI, gtp_val, "Unknown message"));
      ext_tree_rai = proto_item_add_subtree(te, ett_gtp_rai);

      byte[0] = tvb_get_guint8 (tvb, offset + 1);
      byte[1] = tvb_get_guint8 (tvb, offset + 2);
      byte[2] = tvb_get_guint8 (tvb, offset + 3);
      mcc = (byte[0] & 0x0F) * 100 + ((byte[0] & 0xF0) >> 4) * 10  + (byte[1] & 0x0F );
      if ((byte[1] & 0xF0) == 0xF0)
            mnc = (byte[2] & 0x0F) * 10  + ((byte[2] & 0xF0) >> 4);
      else
            mnc = (byte[2] & 0x0F) * 100 + ((byte[2] & 0xF0) >> 4 ) * 10  + ((byte[1] & 0xF0) >> 4);

      proto_tree_add_uint(ext_tree_rai, hf_gtp_rai_mcc, tvb, offset+1, 2, mcc);
      proto_tree_add_uint(ext_tree_rai, hf_gtp_rai_mnc, tvb, offset+2, 2, mnc);
      proto_tree_add_uint(ext_tree_rai, hf_gtp_rai_lac, tvb, offset+4, 2, tvb_get_ntohs (tvb, offset+4));
      proto_tree_add_uint(ext_tree_rai, hf_gtp_rai_rac, tvb, offset+6, 1, tvb_get_guint8 (tvb, offset+6));

      return 7;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.4, page 39
 * UMTS:    29.060 v4.0, chapter 7.7.4, page 47
 */
static int
decode_gtp_tlli(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint32     tlli;

      tlli = tvb_get_ntohl(tvb, offset+1);
      proto_tree_add_uint(tree, hf_gtp_tlli, tvb, offset, 5, tlli);

      return 5;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.5, page 39
 * UMTS:    29.060 v4.0, chapter 7.7.5, page 47
 */
static int
decode_gtp_ptmsi(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint32     ptmsi;

      ptmsi = tvb_get_ntohl (tvb, offset+1);
      proto_tree_add_uint (tree, hf_gtp_ptmsi, tvb, offset, 5, ptmsi);

      return 5;
}

/* adjust - how many bytes before offset should be highlighted
 */
static int
decode_qos_gprs(tvbuff_t *tvb, int offset, proto_tree *tree, const gchar* qos_str, guint8 adjust) {

      guint8            spare1, delay, reliability, peak, spare2,  precedence, spare3, mean;
      proto_tree  *ext_tree_qos;
      proto_item  *te;

      spare1 = tvb_get_guint8(tvb, offset) & 0xC0;
      delay = tvb_get_guint8(tvb, offset) & 0x38;
      reliability = tvb_get_guint8(tvb, offset) & 0x07;
      peak = tvb_get_guint8(tvb, offset+1) & 0xF0;
      spare2 = tvb_get_guint8(tvb, offset+1) & 0x08;
      precedence = tvb_get_guint8(tvb, offset+1) & 0x07;
      spare3 = tvb_get_guint8(tvb, offset+2) & 0xE0;
      mean = tvb_get_guint8(tvb, offset+2) & 0x1F;

      te = proto_tree_add_text(tree, tvb, offset-adjust, 3+adjust, "%s: delay: %u, reliability: %u, peak: %u, precedence: %u, mean: %u",
                                                                qos_str, (delay >> 3) & 0x07, reliability, (peak >> 4) & 0x0F, precedence, mean);
      ext_tree_qos = proto_item_add_subtree(te, ett_gtp_qos);

      if (adjust != 0) {
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_spare1, tvb, offset, 1, spare1);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_delay, tvb, offset, 1, delay);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_reliability, tvb, offset, 1, reliability);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_peak, tvb, offset+1, 1, peak);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_spare2, tvb, offset+1, 1, spare2);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_precedence, tvb, offset+1, 1, precedence);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_spare3, tvb, offset+2, 1, spare3);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_mean, tvb, offset+2, 1, mean);
      }

      return 3;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.6, page 39
 *          4.08
 *          3.60
 * UMTS:    not present
 * TODO:    check if length is included: ETSI 4.08 vs 9.60
 */
static int
decode_gtp_qos_gprs(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      return (1+decode_qos_gprs(tvb, offset+1, tree, "Quality of Service", 1));

}

/* GPRS:    9.60 v7.6.0, chapter 7.9.7, page 39
 * UMTS:    29.060 v4.0, chapter 7.7.6, page 47
 */
static int
decode_gtp_reorder(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      reorder;

      reorder = tvb_get_guint8(tvb, offset+1) & 0x01;
      proto_tree_add_boolean(tree, hf_gtp_reorder, tvb, offset, 2, reorder);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.8, page 40
 *          4.08 v7.1.2, chapter 10.5.3.1+
 * UMTS:    29.060 v4.0, chapter 7.7.7
 * TODO: Add blurb support by registering items in the protocol registration
 */
static int
decode_gtp_auth_tri(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      proto_tree  *ext_tree_auth_tri;
      proto_item  *te;

      te = proto_tree_add_text(tree, tvb, offset, 29, val_to_str(GTP_EXT_AUTH_TRI, gtp_val, "Unknown message"));
      ext_tree_auth_tri = proto_item_add_subtree(tree, ett_gtp_auth_tri);

      proto_tree_add_text(ext_tree_auth_tri, tvb, offset+1, 16, "RAND: %s", tvb_bytes_to_str(tvb, offset+1, 16));
      proto_tree_add_text(ext_tree_auth_tri, tvb, offset+17, 4, "SRES: %s", tvb_bytes_to_str(tvb, offset+17, 4));
      proto_tree_add_text(ext_tree_auth_tri, tvb, offset+21, 8, "Kc: %s", tvb_bytes_to_str(tvb, offset+21, 8));

      return 1+16+4+8;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.9, page 40
 *          9.02 v7.7.0, page 1090
 * UMTS:    29.060 v4.0, chapter 7.7.8, page 48
 *          29.002 v4.2.1, chapter 17.5, page 268
 */
static int
decode_gtp_map_cause(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      map_cause;

      map_cause = tvb_get_guint8(tvb, offset+1);
      proto_tree_add_uint (tree, hf_gtp_map_cause, tvb, offset, 2, map_cause);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.10, page 41
 * UMTS:    29.060 v4.0, chapter 7.7.9, page 48
 */
static int
decode_gtp_ptmsi_sig(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint32     ptmsi_sig;

      ptmsi_sig = tvb_get_ntoh24(tvb, offset+1);
      proto_tree_add_uint(tree, hf_gtp_ptmsi_sig, tvb, offset, 4, ptmsi_sig);

      return 4;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.11, page 41
 * UMTS:    29.060 v4.0, chapter 7.7.10, page 49
 */
static int
decode_gtp_ms_valid(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      ms_valid;

      ms_valid = tvb_get_guint8(tvb, offset+1) & 0x01;
      proto_tree_add_boolean (tree, hf_gtp_ms_valid, tvb, offset, 2, ms_valid);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.12, page 41
 * UMTS:    29.060 v4.0, chapter 7.7.11, page 49
 */
static int
decode_gtp_recovery(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      recovery;

      recovery = tvb_get_guint8(tvb, offset+1);
      proto_tree_add_uint (tree, hf_gtp_recovery, tvb, offset, 2, recovery);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.13, page 42
 * UMTS:    29.060 v4.0, chapter 7.7.12, page 49
 */
static int
decode_gtp_sel_mode(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      sel_mode;

      sel_mode = tvb_get_guint8(tvb, offset+1) & 0x03;
      proto_tree_add_uint(tree, hf_gtp_sel_mode, tvb, offset, 2, sel_mode);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.14, page 42
 * UMTS:    29.060 v4.0, chapter 7.7.13, page 50
 */
static int
decode_gtp_16(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16     ext_flow_label;
      guint32     teid_data;

      switch (gtp_version) {
            case 0:
                  ext_flow_label = tvb_get_ntohs(tvb, offset+1);
                  proto_tree_add_uint(tree, hf_gtp_ext_flow_label, tvb, offset, 3, ext_flow_label);

                  return 3;
            case 1:
                  teid_data = tvb_get_ntohl(tvb, offset+1);
                  proto_tree_add_uint(tree, hf_gtp_teid_data, tvb, offset, 5, teid_data);

                  return 5;
            default:
                  proto_tree_add_text(tree, tvb, offset, 1, "Flow label/TEID Data I : GTP version not supported");

                  return 3;
      }
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.15, page 42
 * UMTS:    29.060 v4.0, chapter 7.7.14, page 42
 */
static int
decode_gtp_17(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           flow_sig;
      guint32           teid_cp;

      switch (gtp_version) {
            case 0:
                  flow_sig = tvb_get_ntohs(tvb, offset+1);
                  proto_tree_add_uint (tree, hf_gtp_flow_sig, tvb, offset, 3, flow_sig);
                  return 3;
            case 1:
                  teid_cp = tvb_get_ntohl(tvb, offset+1);
                  proto_tree_add_uint (tree, hf_gtp_teid_cp, tvb, offset, 5, teid_cp);
                  return 5;
            default:
                  proto_tree_add_text(tree, tvb, offset, 1, "Flow label signalling/TEID control plane : GTP version not supported");
                  return 3;
      }
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.16, page 42
 * UMTS:    29.060 v4.0, chapter 7.7.15, page 51
 */
static int
decode_gtp_18(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           flow_ii;
      guint32           teid_ii;
      proto_tree  *ext_tree_flow_ii;
      proto_item  *te;

      switch (gtp_version) {
            case 0:
                  te = proto_tree_add_text(tree, tvb, offset, 4, val_to_str(GTP_EXT_FLOW_II, gtp_val, "Unknown message"));
                  ext_tree_flow_ii = proto_item_add_subtree (te, ett_gtp_flow_ii);

                  proto_tree_add_uint(ext_tree_flow_ii, hf_gtp_nsapi, tvb, offset+1, 1, tvb_get_guint8(tvb, offset+1) & 0x0F);

                  flow_ii = tvb_get_ntohs(tvb, offset+2);
                  proto_tree_add_uint(ext_tree_flow_ii, hf_gtp_flow_ii, tvb, offset+2, 2, flow_ii);

                  return 4;
            case 1:
                  te = proto_tree_add_text (tree, tvb, offset, 6, val_to_str(GTP_EXT_TEID_II, gtpv1_val, "Unknown message"));
                  ext_tree_flow_ii = proto_item_add_subtree(te, ett_gtp_flow_ii);

                  proto_tree_add_uint(ext_tree_flow_ii, hf_gtp_nsapi, tvb, offset+1, 1, tvb_get_guint8(tvb, offset+1) & 0x0F);


                  teid_ii = tvb_get_ntohl(tvb, offset+2);
                  proto_tree_add_uint(ext_tree_flow_ii, hf_gtp_teid_ii, tvb, offset+2, 4, teid_ii);

                  return 6;
            default:
                  proto_tree_add_text(tree, tvb, offset, 1, "Flow data II/TEID Data II : GTP Version not supported");

                  return 4;
      }
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.16A, page 43
 * UMTS:    29.060 v4.0, chapter 7.7.16, page 51
 * Check if all ms_reason types are included
 */
static int
decode_gtp_19(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            field19;

      field19 = tvb_get_guint8(tvb, offset+1);

      switch (gtp_version) {
            case 0:
                  proto_tree_add_uint(tree, hf_gtp_ms_reason, tvb, offset, 2, field19);
                  break;
            case 1:
                  proto_tree_add_boolean(tree, hf_gtp_tear_ind, tvb, offset, 2, field19 & 0x01);
                  break;
            default:
                  proto_tree_add_text(tree, tvb, offset, 1, "Information Element Type = 19 : GTP Version not supported");
                  break;
      }

      return 2;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.17, page 51
 */
static int
decode_gtp_nsapi(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            nsapi;

      nsapi = tvb_get_guint8(tvb, offset+1) & 0x0F;
      proto_tree_add_uint(tree, hf_gtp_nsapi, tvb, offset, 2, nsapi);

      return 2;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.18, page 52
 */
static int
decode_gtp_ranap_cause(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            ranap;

      ranap = tvb_get_guint8(tvb, offset+1);

      if(ranap > 0 && ranap <=64)
            proto_tree_add_uint_format(tree, hf_gtp_ranap_cause, tvb, offset, 2,
                  ranap, "%s (Radio Network Layer Cause) : %s (%u)",
                  val_to_str(GTP_EXT_RANAP_CAUSE, gtp_val, "Unknown"),
                  val_to_str(ranap, ranap_cause_type, "Unknown RANAP Cause"), ranap);

      if(ranap > 64 && ranap <=80)
            proto_tree_add_uint_format(tree, hf_gtp_ranap_cause, tvb, offset, 2,
                  ranap, "%s (Transport Layer Cause) : %s (%u)",
                  val_to_str(GTP_EXT_RANAP_CAUSE, gtp_val, "Unknown"),
                  val_to_str(ranap, ranap_cause_type, "Unknown RANAP Cause"), ranap);

      if(ranap > 80 && ranap <=96)
            proto_tree_add_uint_format(tree, hf_gtp_ranap_cause, tvb, offset, 2,
                  ranap, "%s (NAS Cause) : %s (%u)",
                  val_to_str(GTP_EXT_RANAP_CAUSE, gtp_val, "Unknown"),
                  val_to_str(ranap, ranap_cause_type, "Unknown RANAP Cause"), ranap);

      if(ranap > 96 && ranap <=112)
            proto_tree_add_uint_format(tree, hf_gtp_ranap_cause, tvb, offset, 2, ranap,
                  "%s (Protocol Cause) : %s (%u)",
                  val_to_str(GTP_EXT_RANAP_CAUSE, gtp_val, "Unknown"),
                  val_to_str(ranap, ranap_cause_type, "Unknown RANAP Cause"), ranap);

      if(ranap > 112 && ranap <=128)
            proto_tree_add_uint_format(tree, hf_gtp_ranap_cause, tvb, offset, 2, ranap,
                  "%s (Miscellaneous Cause) : %s (%u)",
                  val_to_str(GTP_EXT_RANAP_CAUSE, gtp_val, "Unknown"),
                  val_to_str(ranap, ranap_cause_type, "Unknown RANAP Cause"), ranap);

      if(ranap > 128 /* && ranap <=255 */)
            proto_tree_add_uint_format(tree, hf_gtp_ranap_cause, tvb, offset, 2, ranap,
                  "%s (Non-standard Cause) : %s (%u)",
                  val_to_str(GTP_EXT_RANAP_CAUSE, gtp_val, "Unknown"),
                  val_to_str(ranap, ranap_cause_type, "Unknown RANAP Cause"), ranap);

      return 2;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.19, page 52
 */
static int
decode_gtp_rab_cntxt(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            nsapi;
      proto_tree  *ext_tree_rab_cntxt;
      proto_item  *te;

      te = proto_tree_add_text(tree, tvb, offset, 10, val_to_str(GTP_EXT_RAB_CNTXT, gtp_val, "Unknown message"));
      ext_tree_rab_cntxt = proto_item_add_subtree(te, ett_gtp_rab_cntxt);

      nsapi = tvb_get_guint8(tvb, offset+1) & 0x0F;

      proto_tree_add_uint (ext_tree_rab_cntxt, hf_gtp_nsapi, tvb, offset+1, 1, nsapi);
      proto_tree_add_item(ext_tree_rab_cntxt, hf_gtp_rab_gtpu_dn, tvb, offset+2, 2, FALSE);
      proto_tree_add_item(ext_tree_rab_cntxt, hf_gtp_rab_gtpu_up, tvb, offset+4, 2, FALSE);
      proto_tree_add_item(ext_tree_rab_cntxt, hf_gtp_rab_pdu_dn, tvb, offset+6, 2, FALSE);
      proto_tree_add_item(ext_tree_rab_cntxt, hf_gtp_rab_pdu_up, tvb, offset+8, 2, FALSE);

      return 10;
}


/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.20, page 53
 */
static int
decode_gtp_rp_sms(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            rp_sms;

      rp_sms = tvb_get_guint8(tvb, offset+1) & 0x07;
      proto_tree_add_uint(tree, hf_gtp_rp_sms, tvb, offset, 2, rp_sms);

      return 2;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.21, page 53
 */
static int
decode_gtp_rp(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      proto_tree  *ext_tree_rp;
      proto_item  *te;
      guint8            nsapi, rp, spare;

      nsapi = tvb_get_guint8(tvb, offset+1) & 0xF0;
      spare = tvb_get_guint8(tvb, offset+1) & 0x08;
      rp = tvb_get_guint8(tvb, offset+1) & 0x07;

      te = proto_tree_add_uint_format(tree, hf_gtp_rp, tvb, offset, 2, rp, "Radio Priority for NSAPI(%u) : %u", nsapi, rp);
      ext_tree_rp = proto_item_add_subtree(tree, ett_gtp_rp);

      proto_tree_add_uint(ext_tree_rp, hf_gtp_rp_nsapi, tvb, offset+1, 1, nsapi);
      proto_tree_add_uint(ext_tree_rp, hf_gtp_rp_spare, tvb, offset+1, 1, spare);
      proto_tree_add_uint(ext_tree_rp, hf_gtp_rp, tvb, offset+1, 1, rp);

      return 2;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.22, page 53
 */
static int
decode_gtp_pkt_flow_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      proto_tree  *ext_tree_pkt_flow_id;
      proto_item  *te;
      guint8            nsapi, pkt_flow_id;

      nsapi = tvb_get_guint8(tvb, offset+1) & 0x0F;
      pkt_flow_id = tvb_get_guint8(tvb, offset+2);

      te = proto_tree_add_uint_format (tree, hf_gtp_pkt_flow_id, tvb, offset,
            3, pkt_flow_id, "Packet Flow ID for NSAPI(%u) : %u", nsapi,
            pkt_flow_id);
      ext_tree_pkt_flow_id = proto_item_add_subtree(tree, ett_gtp_pkt_flow_id);

      proto_tree_add_uint(ext_tree_pkt_flow_id, hf_gtp_nsapi, tvb, offset+1, 1, nsapi);
      proto_tree_add_uint_format(ext_tree_pkt_flow_id, hf_gtp_pkt_flow_id, tvb,
            offset+2, 1, pkt_flow_id, "%s : %u",
            val_to_str(GTP_EXT_PKT_FLOW_ID, gtp_val, "Unknown message"),
            pkt_flow_id);

      return 3;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.23, page 53
 * TODO: Differenciate these uints?
 */
static int
decode_gtp_chrg_char(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           chrg_char;
      proto_item  *te;
      proto_tree  *ext_tree_chrg_char;

      chrg_char = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_uint (tree, hf_gtp_chrg_char, tvb, offset, 3, chrg_char);
      /*"%s: %x", val_to_str (GTP_EXT_CHRG_CHAR, gtp_val, "Unknown message"), chrg_char);*/
      ext_tree_chrg_char = proto_item_add_subtree(te, ett_gtp_chrg_char);

      proto_tree_add_uint (ext_tree_chrg_char, hf_gtp_chrg_char_s, tvb, offset+1, 2, chrg_char);
      proto_tree_add_uint (ext_tree_chrg_char, hf_gtp_chrg_char_n, tvb, offset+1, 2, chrg_char);
      proto_tree_add_uint (ext_tree_chrg_char, hf_gtp_chrg_char_p, tvb, offset+1, 2, chrg_char);
      proto_tree_add_uint (ext_tree_chrg_char, hf_gtp_chrg_char_f, tvb, offset+1, 2, chrg_char);
      proto_tree_add_uint (ext_tree_chrg_char, hf_gtp_chrg_char_h, tvb, offset+1, 2, chrg_char);
      proto_tree_add_uint (ext_tree_chrg_char, hf_gtp_chrg_char_r, tvb, offset+1, 2, chrg_char);

      return 3;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.24, page
 */
static int
decode_gtp_trace_ref(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           trace_ref;

      trace_ref = tvb_get_ntohs(tvb, offset+1);

      proto_tree_add_uint (tree, hf_gtp_trace_ref, tvb, offset, 3, trace_ref);

      return 3;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.25, page
 */
static int
decode_gtp_trace_type(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           trace_type;

      trace_type = tvb_get_ntohs(tvb, offset+1);

      proto_tree_add_uint (tree, hf_gtp_trace_type, tvb, offset, 3, trace_type);

      return 3;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.16A
 * UMTS:    29.060 v4.0, chapter 7.7.25A, page
 */
static int
decode_gtp_ms_reason(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            reason;

      reason = tvb_get_guint8(tvb, offset+1);

      proto_tree_add_uint (tree, hf_gtp_ms_reason, tvb, offset, 2, reason);

      return 2;
}

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.25B
 * Radio Priority LCS
 */
 static int
decode_gtp_ra_prio_lcs(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_RA_PRIO_LCS, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_ra_prio_lcs);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

  }

/* GPRS:    12.15 v7.6.0, chapter 7.3.3, page 45
 * UMTS:    33.015
 */
static int
decode_gtp_tr_comm(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8      tr_command;

      tr_command = tvb_get_guint8(tvb, offset+1);

      proto_tree_add_uint (tree, hf_gtp_tr_comm, tvb, offset, 2, tr_command);

      return 2;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.17, page 43
 * UMTS:    29.060 v4.0, chapter 7.7.26, page 55
 */
static int
decode_gtp_chrg_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint32     chrg_id;

      chrg_id = tvb_get_ntohl(tvb, offset+1);
      proto_tree_add_uint (tree, hf_gtp_chrg_id, tvb, offset, 5, chrg_id);

      return 5;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.18, page 43
 * UMTS:    29.060 v4.0, chapter 7.7.27, page 55
 */
static int
decode_gtp_user_addr(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      guint8            pdp_typ, pdp_org;
      guint32           addr_ipv4;
      struct            e_in6_addr addr_ipv6;
      proto_tree  *ext_tree_user;
      proto_item  *te;


      length = tvb_get_ntohs(tvb, offset+1);
      pdp_org = tvb_get_guint8(tvb, offset+3) & 0x0F;
      pdp_typ = tvb_get_guint8(tvb, offset+4);

      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s (%s/%s)",
          val_to_str(GTP_EXT_USER_ADDR, gtp_val, "Unknown message"),
          val_to_str(pdp_org, pdp_org_type, "Unknown PDP Organization"),
          val_to_str(pdp_typ, pdp_type, "Unknown PDP Type"));
      ext_tree_user = proto_item_add_subtree(te, ett_gtp_user);

      proto_tree_add_text(ext_tree_user, tvb, offset+1, 2, "Length : %u", length);
      proto_tree_add_uint(ext_tree_user, hf_gtp_user_addr_pdp_org, tvb, offset+3, 1, pdp_org);
      proto_tree_add_uint(ext_tree_user, hf_gtp_user_addr_pdp_type, tvb, offset+4, 1, pdp_typ);

      if (length == 2) {
            if (pdp_org == 0 && pdp_typ == 1)
                  proto_item_append_text(te, " (Point to Point Protocol)");
            else if (pdp_typ == 2)
                  proto_item_append_text(te, " (Octet Stream Protocol)");
      } else if (length > 2) {
            switch (pdp_typ) {
                  case 0x21:
                        addr_ipv4 = tvb_get_ipv4(tvb, offset+5);
                        proto_tree_add_ipv4(ext_tree_user, hf_gtp_user_ipv4, tvb, offset+5, 4, addr_ipv4);
                        proto_item_append_text(te, " : %s", ip_to_str((guint8 *)&addr_ipv4));
                        break;
                  case 0x57:
                        tvb_get_ipv6(tvb, offset+5, &addr_ipv6);
                        proto_tree_add_ipv6 (ext_tree_user, hf_gtp_user_ipv6, tvb, offset+5, 16, (guint8 *)&addr_ipv6);
                        proto_item_append_text(te, " : %s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                        break;
            }
      } else
            proto_item_append_text(te, " : empty PDP Address");

      return 3+length;
}

static int
decode_triplet(tvbuff_t *tvb, int offset, proto_tree *tree, guint16 count) {

      proto_tree  *ext_tree_trip;
      proto_item  *te_trip;
      guint16           i;

      for (i=0;i<count;i++) {
            te_trip = proto_tree_add_text(tree, tvb, offset+i*28, 28, "Triplet no%x", i);
            ext_tree_trip = proto_item_add_subtree(te_trip, ett_gtp_trip);

            proto_tree_add_text(ext_tree_trip, tvb, offset+i*28, 16, "RAND: %s", tvb_bytes_to_str(tvb, offset+i*28, 16));
            proto_tree_add_text(ext_tree_trip, tvb, offset+i*28+16, 4, "SRES: %s", tvb_bytes_to_str(tvb, offset+i*28+16, 4));
            proto_tree_add_text(ext_tree_trip, tvb, offset+i*28+20, 8, "Kc: %s", tvb_bytes_to_str(tvb, offset+i*28+20, 8));
      }

      return count*28;
}

/* adjust - how many bytes before quintuplet should be highlighted
 */
static int
decode_quintuplet(tvbuff_t *tvb, int offset, proto_tree *tree, guint16 count) {

      proto_tree  *ext_tree_quint;
      proto_item  *te_quint;
      guint16           q_offset, i;
      guint8          xres_len, auth_len;

      q_offset = 0;

      for (i=0;i<count;i++) {

            te_quint = proto_tree_add_text(tree, tvb, offset, -1, "Quintuplet #%x", i+1);
            ext_tree_quint = proto_item_add_subtree(te_quint, ett_gtp_quint);


            proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 16, "RAND: %s", tvb_bytes_to_str(tvb, offset, 16));
            q_offset = q_offset + 16;
            xres_len = tvb_get_guint8(tvb, offset+q_offset);
            proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 1, "XRES length: %u", xres_len);
            q_offset++;
            proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, xres_len, "XRES: %s", tvb_bytes_to_str(tvb, offset + q_offset, xres_len));
            q_offset = q_offset + xres_len;
            proto_tree_add_text(ext_tree_quint, tvb ,offset + q_offset, 16, "Quintuplet Ciphering Key: %s", tvb_bytes_to_str(tvb, offset + q_offset, 16));
            q_offset = q_offset + 16;
            proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 16, "Quintuplet Integrity Key: %s", tvb_bytes_to_str(tvb, offset + q_offset, 16));
            q_offset = q_offset +16;
            auth_len = tvb_get_guint8(tvb, offset + q_offset);
            proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 1, "Authentication length: %u", auth_len);
            q_offset++;
            proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, auth_len, "AUTH: %s", tvb_bytes_to_str(tvb, offset + q_offset, auth_len));

            q_offset = q_offset+auth_len;
            proto_item_set_end(te_quint, tvb, offset+q_offset);

      }

      return q_offset;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.19 page
 * UMTS:    29.060 v4.0, chapter 7.7.28 page 57
 * TODO:    - check if for quintuplets first 2 bytes are length, according to AuthQuint
 *          - finish displaying last 3 parameters
 */
static int
decode_gtp_mm_cntxt(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, quint_len, con_len;
      guint8            cksn, count, sec_mode, len;
      proto_tree  *ext_tree_mm;
      proto_item  *te;
    proto_item  *tf = NULL;
    proto_tree  *tf_tree = NULL;
      tvbuff_t    *l3_tvb;


      te = proto_tree_add_text(tree, tvb, offset, 1, val_to_str(GTP_EXT_MM_CNTXT, gtp_val, "Unknown message"));
      ext_tree_mm = proto_item_add_subtree(te, ett_gtp_mm);

      /* Octet 2 - 3 */
      length = tvb_get_ntohs(tvb, offset+1);
      if (length < 1) return 3;

      /* Octet 4 */
      cksn = tvb_get_guint8(tvb, offset+3) & 0x07;
      /* Octet 5 */
      sec_mode = (tvb_get_guint8(tvb, offset+4) >> 6) & 0x03;
      count = (tvb_get_guint8(tvb, offset+4) >> 3) & 0x07;

      proto_tree_add_text(ext_tree_mm, tvb, offset+1, 2, "Length: %x", length);
      if (gtp_version == 0)
            sec_mode = 1;


      switch (sec_mode) {
            case 0:                       /* Used cipher value, UMTS keys and Quintuplets */
                  proto_tree_add_item(ext_tree_mm, hf_gtp_cksn_ksi, tvb, offset+3, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_security_mode, tvb, offset+4, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_no_of_vectors, tvb, offset+4, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_cipher_algorithm, tvb, offset+4, 1, FALSE);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+5, 16, "Ciphering key CK: %s", tvb_bytes_to_str(tvb, offset+5, 16));
                  proto_tree_add_text(ext_tree_mm, tvb, offset+21, 16, "Integrity key IK: %s", tvb_bytes_to_str(tvb, offset+21, 16));
                  quint_len = tvb_get_ntohs(tvb, offset+37);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+37, 2, "Quintuplets length: 0x%x (%u)", quint_len, quint_len);

                  offset = offset + decode_quintuplet(tvb, offset+39, ext_tree_mm, count) + 39;


                  break;
            case 1:                       /* GSM key and triplets */
                  proto_tree_add_item(ext_tree_mm, hf_gtp_cksn, tvb, offset+3, 1, FALSE);
                  if (gtp_version != 0)
                        proto_tree_add_item(ext_tree_mm, hf_gtp_security_mode, tvb, offset+4, 1, FALSE);

                  proto_tree_add_item(ext_tree_mm, hf_gtp_no_of_vectors, tvb, offset+4, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_cipher_algorithm, tvb, offset+4, 1, FALSE);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+5, 8, "Ciphering key Kc: %s", tvb_bytes_to_str(tvb, offset+5, 8));

                  offset = offset + decode_triplet(tvb, offset+13, ext_tree_mm, count) + 13;

                  break;
            case 2:                       /* UMTS key and quintuplets */
                  proto_tree_add_item(ext_tree_mm, hf_gtp_ksi, tvb, offset+3, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_security_mode, tvb, offset+4, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_no_of_vectors, tvb, offset+4, 1, FALSE);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+5, 16, "Ciphering key CK: %s", tvb_bytes_to_str(tvb, offset+5, 16));
                  proto_tree_add_text(ext_tree_mm, tvb, offset+21, 16, "Integrity key IK: %s", tvb_bytes_to_str(tvb, offset+21, 16));
                  quint_len = tvb_get_ntohs(tvb, offset+37);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+37, 2, "Quintuplets length: 0x%x (%u)", quint_len, quint_len);

                  offset = offset + decode_quintuplet(tvb, offset+39, ext_tree_mm, count) + 39;

                  break;
            case 3:                       /* GSM key and quintuplets */
                  proto_tree_add_item(ext_tree_mm, hf_gtp_cksn, tvb, offset+3, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_security_mode, tvb, offset+4, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_no_of_vectors, tvb, offset+4, 1, FALSE);
                  proto_tree_add_item(ext_tree_mm, hf_gtp_cipher_algorithm, tvb, offset+4, 1, FALSE);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+5, 8, "Ciphering key Kc: %s", tvb_bytes_to_str(tvb, offset+5, 8));
                  quint_len = tvb_get_ntohs(tvb, offset+13);
                  proto_tree_add_text(ext_tree_mm, tvb, offset+13, 2, "Quintuplets length: 0x%x (%u)", quint_len, quint_len);

                  offset = offset + decode_quintuplet(tvb, offset+15, ext_tree_mm, count) + 15;

                  break;
            default:
                  break;
      }

/*
 * 3GPP TS 24.008 10.5.5.6 ( see packet-gsm_a.c )
 */
      de_gmm_drx_param(tvb, ext_tree_mm, offset, 2, NULL, 0);
      offset = offset +2;

      len   = tvb_get_guint8(tvb, offset);
    tf = proto_tree_add_text(ext_tree_mm,
      tvb, offset, len+1,
      "MS Network Capability");

    tf_tree = proto_item_add_subtree(tf, ett_gtp_net_cap);

      proto_tree_add_text(tf_tree, tvb, offset, 1, "Length of MS network capability contents: %u", len);

      offset++;
/*
 * GPP TS 24.008 10.5.5.12 ( see packet-gsm_a.c )
 */
      de_gmm_ms_net_cap(tvb, tf_tree, offset, len, NULL, 0);
      offset = offset +len;

/* Container contains one or several optional information elements as described in the clause 'Overview',
 * from the clause 'General message format and information elements coding' in 3GPP TS 24.008.
 * The IMEISV shall, if available, be included in the Container.
 */

      con_len = tvb_get_ntohs(tvb, offset);
      proto_tree_add_text(ext_tree_mm, tvb, offset, 2, "Container length: %u", con_len);
      offset = offset + 2;

      if (con_len > 0) {

            l3_tvb = tvb_new_subset(tvb, offset,con_len, con_len );
            if  (!dissector_try_port(bssap_pdu_type_table,BSSAP_PDU_TYPE_DTAP, l3_tvb, pinfo, ext_tree_mm))
                        call_dissector(data_handle, l3_tvb, pinfo, ext_tree_mm);
      }

      return 3+length;
}

/* Function to extract the value of an hexadecimal octet. Only the lower
 * nybble will be non-zero in the output.
 * */
static guint8 hex2dec (guint8 x)
{
      if ((x >= 'a') && (x <= 'f'))
            x = x - 'a' + 10;
      else if ((x >= 'A') && (x <= 'F'))
            x = x - 'A' + 10;
      else if ((x >= '0') && (x <= '9'))
            x = x - '0';
      else
            x = 0;
      return x;
}

/* Wrapper function to add UTF-8 decoding for QoS attributes in
 * RADIUS messages.
 * */
static guint8 wrapped_tvb_get_guint8( tvbuff_t *tvb, int offset, int type)
{
      if (type == 2)
            return (hex2dec(tvb_get_guint8(tvb, offset)) << 4
                              | hex2dec(tvb_get_guint8(tvb, offset + 1)));
      else
            return tvb_get_guint8(tvb, offset);
}

 /* WARNING : actually length is coded on 2 octets for QoS profile but on 1 octet for PDP Context!
  * so type means length of length :-)
  *
  * WARNING :) type does not mean length of length any more... see below for
  * type = 3!
 */
static int
decode_qos_umts(tvbuff_t *tvb, int offset, proto_tree *tree, const gchar* qos_str, guint8 type) {

      guint       length;
      guint8            al_ret_priority;
      guint8            delay, reliability, peak, precedence, mean, spare1, spare2, spare3;
      guint8            traf_class, del_order, del_err_sdu;
      guint8            max_sdu_size, max_ul, max_dl;
      guint8            res_ber, sdu_err_ratio;
      guint8            trans_delay, traf_handl_prio;
      guint8            guar_ul, guar_dl;
      proto_tree  *ext_tree_qos;
      proto_item  *te;
      int         mss, mu, md, gu, gd;

      /* Will keep if the input is UTF-8 encoded (as in RADIUS messages).
       * If 1, input is *not* UTF-8 encoded (i.e. each input octet corresponds
       * to one byte to be dissected).
       * If 2, input is UTF-8 encoded (i.e. each *couple* of input octets
       * corresponds to one byte to be dissected)
       * */
      guint8      utf8_type = 1;

      /* In RADIUS messages the QoS has a version field of two octets prepended.
       * As of 29.061 v.3.a.0, there is an hyphen between "Release Indicator" and
       * <release specific QoS IE UTF-8 encoding>. Even if it sounds rather
       * inconsistent and unuseful, I will check hyphen presence here and
       * will signal its presence.
       * */
      guint8      hyphen;

      /* Will keep the value that will be returned
       * */
      int         retval = 0;

      switch (type) {
            case 1:
                  length = tvb_get_guint8 (tvb, offset);
                  te = proto_tree_add_text (tree, tvb, offset, length + 1, "%s", qos_str);
                  ext_tree_qos = proto_item_add_subtree (te, ett_gtp_qos);
                  proto_tree_add_text (ext_tree_qos, tvb, offset, 1, "Length: %u", length);
                  offset++;
                  retval = length + 1;
                  break;
            case 2:
                  length = tvb_get_ntohs (tvb, offset + 1);
                  te = proto_tree_add_text(tree, tvb, offset, length + 3, "%s", qos_str);
                  ext_tree_qos = proto_item_add_subtree (te, ett_gtp_qos);
                  proto_tree_add_text (ext_tree_qos, tvb, offset + 1, 2, "Length: %u", length);
                  offset += 3;            /* +1 because of first 0x86 byte for UMTS QoS */
                  retval = length + 3;
                  break;
            case 3:
                  /* For QoS inside RADIUS Client messages from GGSN */
                  utf8_type = 2;

                  /* The field in the RADIUS message is the length of the tvb we were given */
                  length = tvb_length(tvb);
                  te = proto_tree_add_text (tree, tvb, offset, length, "%s", qos_str);

                  ext_tree_qos = proto_item_add_subtree (te, ett_gtp_qos);

                  proto_tree_add_item (ext_tree_qos, hf_gtp_qos_version, tvb, offset, 2, FALSE);

                  /* Hyphen handling */
                  hyphen = tvb_get_guint8(tvb, offset + 2);
                  if (hyphen == ((guint8) '-'))
                  {
                        /* Hyphen is present, put in protocol tree */
                        proto_tree_add_text (ext_tree_qos, tvb, offset + 2, 1, "Hyphen separator: -");
                        offset++; /* "Get rid" of hyphen */
                  }

                  /* Now, we modify offset here and in order to use type later
                   * effectively.*/
                  offset++;

                  length -= offset;
                  length /=2;

                  retval = length + 2;      /* Actually, will be ignored. */
                  break;
            default:
                  /* XXX - what should we do with the length here? */
                  length = 0;
                  retval = 0;
                  ext_tree_qos = NULL;
                  break;
      }

      /* In RADIUS messages there is no allocation-retention priority
       * so I don't need to wrap the following call to tvb_get_guint8
       * */
      al_ret_priority = tvb_get_guint8 (tvb, offset);

      /* All calls are wrapped to take into account the possibility that the
       * input is UTF-8 encoded. If utf8_type is equal to 1, the final value
       * of the offset will be the same as in the previous version of this
       * dissector, and the wrapped function will serve as a dumb wrapper;
       * otherwise, if utf_8_type is 2, the offset is correctly shifted by
       * two bytes for needed shift, and the wrapped function will unencode
       * two values from the input.
       * */
      spare1 = wrapped_tvb_get_guint8(tvb, offset+(1 - 1) * utf8_type + 1, utf8_type) & 0xC0;
      delay = wrapped_tvb_get_guint8(tvb, offset+(1 - 1) * utf8_type + 1, utf8_type) & 0x38;
      reliability = wrapped_tvb_get_guint8(tvb, offset+(1 - 1) * utf8_type + 1, utf8_type) & 0x07;
      peak = wrapped_tvb_get_guint8(tvb, offset+(2 - 1) * utf8_type + 1, utf8_type) & 0xF0;
      spare2 = wrapped_tvb_get_guint8(tvb, offset+(2 - 1) * utf8_type + 1, utf8_type) & 0x08;
      precedence = wrapped_tvb_get_guint8(tvb, offset+(2 - 1) * utf8_type + 1, utf8_type) & 0x07;
      spare3 = wrapped_tvb_get_guint8(tvb, offset+(3 - 1) * utf8_type + 1, utf8_type) & 0xE0;
      mean = wrapped_tvb_get_guint8(tvb, offset+(3 - 1) * utf8_type + 1, utf8_type) & 0x1F;

      /* In RADIUS messages there is no allocation-retention priority */
      if (type != 3)
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_al_ret_priority, tvb, offset, 1, al_ret_priority);

      /* All additions must take care of the fact that QoS fields in RADIUS
       * messages are UTF-8 encoded, so we have to use the same trick as above.
       * */
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_spare1, tvb, offset+(1 - 1) * utf8_type + 1, utf8_type, spare1);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_delay, tvb, offset+(1 - 1) * utf8_type + 1, utf8_type, delay);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_reliability, tvb, offset+(1 - 1) * utf8_type + 1, utf8_type, reliability);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_peak, tvb, offset+(2 - 1) * utf8_type + 1, utf8_type, peak);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_spare2, tvb, offset+(2 - 1) * utf8_type + 1, utf8_type, spare2);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_precedence, tvb, offset+(2 - 1) * utf8_type + 1, utf8_type, precedence);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_spare3, tvb, offset+(3 - 1) * utf8_type + 1, utf8_type, spare3);
      proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_mean, tvb, offset+(3 - 1) * utf8_type + 1, utf8_type, mean);

      if (length > 4) {

            /* See above for the need of wrapping
             * */
            traf_class = wrapped_tvb_get_guint8(tvb, offset+(4 - 1) * utf8_type + 1, utf8_type) & 0xE0;
            del_order = wrapped_tvb_get_guint8(tvb, offset+(4 - 1) * utf8_type + 1, utf8_type) & 0x18;
            del_err_sdu = wrapped_tvb_get_guint8(tvb, offset+(4 - 1) * utf8_type + 1, utf8_type) & 0x07;
            max_sdu_size = wrapped_tvb_get_guint8(tvb, offset+(5 - 1) * utf8_type + 1, utf8_type);
            max_ul = wrapped_tvb_get_guint8(tvb, offset+(6 - 1) * utf8_type + 1, utf8_type);
            max_dl = wrapped_tvb_get_guint8(tvb, offset+(7 - 1) * utf8_type + 1, utf8_type);
            res_ber = wrapped_tvb_get_guint8(tvb, offset+(8 - 1) * utf8_type + 1, utf8_type) & 0xF0;
            sdu_err_ratio = wrapped_tvb_get_guint8(tvb, offset+(8 - 1) * utf8_type + 1, utf8_type) & 0x0F;
            trans_delay = wrapped_tvb_get_guint8(tvb, offset+(9 - 1) * utf8_type + 1, utf8_type) & 0xFC;
            traf_handl_prio = wrapped_tvb_get_guint8(tvb, offset+(9 - 1) * utf8_type + 1, utf8_type) & 0x03;
            guar_ul = wrapped_tvb_get_guint8(tvb, offset+(10 - 1) * utf8_type + 1, utf8_type);
            guar_dl = wrapped_tvb_get_guint8(tvb, offset+(11 - 1) * utf8_type + 1, utf8_type);

            /* See above comments for the changes
             * */
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_traf_class, tvb, offset+(4 - 1) * utf8_type + 1, utf8_type, traf_class);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_del_order, tvb, offset+(4 - 1) * utf8_type + 1, utf8_type, del_order);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_del_err_sdu, tvb, offset+(4 - 1) * utf8_type + 1, utf8_type, del_err_sdu);
            if (max_sdu_size == 0 || max_sdu_size > 150)
                  proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_max_sdu_size, tvb, offset+(5 - 1) * utf8_type + 1, utf8_type, max_sdu_size);
            if (max_sdu_size > 0 && max_sdu_size <= 150) {
                  mss = max_sdu_size*10;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_sdu_size, tvb, offset+(5 - 1) * utf8_type + 1, utf8_type, mss, "Maximum SDU size : %u octets", mss);
            }

            if(max_ul == 0 || max_ul == 255)
                  proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_max_ul, tvb, offset+(6 - 1) * utf8_type + 1, utf8_type, max_ul);
            if(max_ul > 0 && max_ul <= 63)
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_ul, tvb, offset+(6 - 1) * utf8_type + 1, utf8_type, max_ul, "Maximum bit rate for uplink : %u kbps", max_ul);
            if(max_ul > 63 && max_ul <=127) {
                  mu = 64 + ( max_ul - 64 ) * 8;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_ul, tvb, offset+(6 - 1) * utf8_type + 1, utf8_type, mu, "Maximum bit rate for uplink : %u kbps", mu);
            }

            if(max_ul > 127 && max_ul <=254) {
                  mu = 576 + ( max_ul - 128 ) * 64;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_ul, tvb, offset+(6 - 1) * utf8_type + 1, utf8_type, mu, "Maximum bit rate for uplink : %u kbps", mu);
            }

            if(max_dl == 0 || max_dl == 255)
                  proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_max_dl, tvb, offset+(7 - 1) * utf8_type + 1, utf8_type, max_dl);
            if(max_dl > 0 && max_dl <= 63)
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_dl, tvb, offset+(7 - 1) * utf8_type + 1, utf8_type, max_dl, "Maximum bit rate for downlink : %u kbps", max_dl);
            if(max_dl > 63 && max_dl <=127) {
                  md = 64 + ( max_dl - 64 ) * 8;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_dl, tvb, offset+(7 - 1) * utf8_type + 1, utf8_type, md, "Maximum bit rate for downlink : %u kbps", md);
            }
            if(max_dl > 127 && max_dl <=254) {
                  md = 576 + ( max_dl - 128 ) * 64;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_max_dl, tvb, offset+(7 - 1) * utf8_type + 1, utf8_type, md, "Maximum bit rate for downlink : %u kbps", md);
            }

            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_res_ber, tvb, offset+(8 - 1) * utf8_type + 1, utf8_type, res_ber);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_sdu_err_ratio, tvb, offset+(8 - 1) * utf8_type + 1, utf8_type, sdu_err_ratio);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_trans_delay, tvb, offset+(9 - 1) * utf8_type + 1, utf8_type, trans_delay);
            proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_traf_handl_prio, tvb, offset+(9 - 1) * utf8_type + 1, utf8_type, traf_handl_prio);

            if(guar_ul == 0 || guar_ul == 255)
                  proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_guar_ul, tvb, offset+(10 - 1) * utf8_type + 1, utf8_type, guar_ul);
            if(guar_ul > 0 && guar_ul <= 63)
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_guar_ul, tvb, offset+(10 - 1) * utf8_type + 1, utf8_type, guar_ul, "Guaranteed bit rate for uplink : %u kbps", guar_ul);
            if(guar_ul > 63 && guar_ul <=127) {
                  gu = 64 + ( guar_ul - 64 ) * 8;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_guar_ul, tvb, offset+(10 - 1) * utf8_type + 1, utf8_type, gu, "Guaranteed bit rate for uplink : %u kbps", gu);
            }
            if(guar_ul > 127 && guar_ul <=254) {
                  gu = 576 + ( guar_ul - 128 ) * 64;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_guar_ul, tvb, offset+(10 - 1) * utf8_type + 1, utf8_type, gu, "Guaranteed bit rate for uplink : %u kbps", gu);
            }

            if(guar_dl == 0 || guar_dl == 255)
                  proto_tree_add_uint(ext_tree_qos, hf_gtp_qos_guar_dl, tvb, offset+(11 - 1) * utf8_type + 1, utf8_type, guar_dl);
            if(guar_dl > 0 && guar_dl <= 63)
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_guar_dl, tvb, offset+(11 - 1) * utf8_type + 1, utf8_type, guar_dl, "Guaranteed bit rate for downlink : %u kbps", guar_dl);
            if(guar_dl > 63 && guar_dl <=127) {
                  gd = 64 + ( guar_dl - 64 ) * 8;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_guar_dl, tvb, offset+(11 - 1) * utf8_type + 1, utf8_type, gd, "Guaranteed bit rate for downlink : %u kbps", gd);
            }
            if(guar_dl > 127 && guar_dl <=254) {
                  gd = 576 + ( guar_dl - 128 ) * 64;
                  proto_tree_add_uint_format(ext_tree_qos, hf_gtp_qos_guar_dl, tvb, offset+(11 - 1) * utf8_type + 1, utf8_type, gd, "Guaranteed bit rate for downlink : %u kbps", gd);
            }

      }

      return retval;
}

static const gchar* dissect_radius_qos_umts(proto_tree *tree, tvbuff_t *tvb) {
      decode_qos_umts(tvb, 0, tree, "UMTS GTP QoS Profile", 3);
      return tvb_get_ephemeral_string(tvb,0,tvb_length(tvb));
}

static void
decode_apn(tvbuff_t *tvb, int offset, guint16 length, proto_tree *tree) {

      guint8      *apn = NULL;
      int   name_len, tmp;

      if (length > 0) {
            name_len = tvb_get_guint8 (tvb, offset);

            if (name_len < 0x20) {
                  apn = tvb_get_ephemeral_string(tvb, offset + 1, length - 1);
                  for (;;) {
                        if (name_len >= length - 1) break;
                        tmp = name_len;
                        name_len = name_len + apn[tmp] + 1;
                        apn[tmp] = '.';
                  }
            } else
                  apn = tvb_get_ephemeral_string(tvb, offset, length);

            proto_tree_add_string (tree, hf_gtp_apn, tvb, offset, length, apn);
      }
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.20
 * UMTS:    29.060 v4.0, chapter 7.7.29
 * TODO:    unify addr functions
 */
static int
decode_gtp_pdp_cntxt(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            ggsn_addr_len, apn_len, trans_id, vaa, order, nsapi, sapi, pdu_send_no, pdu_rec_no, pdp_cntxt_id,
                  pdp_type_org, pdp_type_num, pdp_addr_len;
      guint16           length, sn_down, sn_up, up_flow;
      guint32     addr_ipv4, up_teid, up_teid_cp;
      struct      e_in6_addr addr_ipv6;
      proto_tree  *ext_tree_pdp;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_text(tree, tvb, offset, length+3, val_to_str(GTP_EXT_PDP_CNTXT, gtp_val, "Unknown message"));
      ext_tree_pdp = proto_item_add_subtree(te, ett_gtp_pdp);

      vaa = (tvb_get_guint8(tvb, offset+3) >> 6) & 0x01;
      order = (tvb_get_guint8(tvb, offset+3) >> 4) & 0x01;
      nsapi =  tvb_get_guint8(tvb, offset+3) & 0x0F;
      sapi = tvb_get_guint8(tvb, offset+4) & 0x0F;

      proto_tree_add_text(ext_tree_pdp, tvb, offset+3, 1, "VPLMN address allowed: %s", yesno[vaa]);
      proto_tree_add_text(ext_tree_pdp, tvb, offset+3, 1, "Reordering required: %s", yesno[order]);
      proto_tree_add_text(ext_tree_pdp, tvb, offset+3, 1, "NSAPI: %u", nsapi);
      proto_tree_add_text(ext_tree_pdp, tvb, offset+4, 1, "SAPI: %u", sapi);

      switch (gtp_version) {
            case 0:
                  decode_qos_gprs(tvb, offset+5, ext_tree_pdp, "QoS subscribed", 0);
                  decode_qos_gprs(tvb, offset+8, ext_tree_pdp, "QoS requested", 0);
                  decode_qos_gprs(tvb, offset+11, ext_tree_pdp, "QoS negotiated", 0);
                  offset = offset + 14;
                  break;
            case 1:
                  offset = offset + 5;
                  offset = offset + decode_qos_umts(tvb, offset, ext_tree_pdp, "QoS subscribed", 1);
                  offset = offset + decode_qos_umts(tvb, offset, ext_tree_pdp, "QoS requested", 1);
                  offset = offset + decode_qos_umts(tvb, offset, ext_tree_pdp, "QoS negotiated", 1);
                  break;
            default:
                  break;
      }

      sn_down = tvb_get_ntohs(tvb, offset);
      sn_up = tvb_get_ntohs(tvb, offset+2);
      pdu_send_no = tvb_get_guint8(tvb, offset+4);
      pdu_rec_no = tvb_get_guint8(tvb, offset+5);

      proto_tree_add_text(ext_tree_pdp, tvb, offset, 2, "Sequence number down: %u", sn_down);
      proto_tree_add_text(ext_tree_pdp, tvb, offset+2, 2, "Sequence number up: %u", sn_up);
      proto_tree_add_text(ext_tree_pdp, tvb, offset+4, 1, "Send N-PDU number: %u", pdu_send_no);
      proto_tree_add_text(ext_tree_pdp, tvb, offset+5, 1, "Receive N-PDU number: %u", pdu_rec_no);

      switch (gtp_version) {
            case 0:
                  up_flow = tvb_get_ntohs(tvb, offset+6);
                  proto_tree_add_text(ext_tree_pdp, tvb, offset+6, 2, "Uplink flow label signalling: %u", up_flow);
                  offset = offset + 8;
                  break;
            case 1:
                  up_teid = tvb_get_ntohl(tvb, offset+6);
                  up_teid_cp = tvb_get_ntohl(tvb, offset+10);
                  pdp_cntxt_id = tvb_get_guint8(tvb, offset+14);
                  proto_tree_add_text(ext_tree_pdp, tvb, offset+6, 4, "Uplink TEID: %x", up_teid);
                  proto_tree_add_text(ext_tree_pdp, tvb, offset+10, 4, "Uplink TEID control plane: %x", up_teid_cp);
                  proto_tree_add_text(ext_tree_pdp, tvb, offset+14, 1, "PDP context identifier: %u", pdp_cntxt_id);
                  offset = offset + 15;
                  break;
            default:
                  break;
      }

      pdp_type_org = tvb_get_guint8(tvb, offset) & 0x0F;
      pdp_type_num = tvb_get_guint8(tvb, offset+1);
      pdp_addr_len = tvb_get_guint8(tvb, offset+2);

      proto_tree_add_text(ext_tree_pdp, tvb, offset, 1, "PDP organization: %s", val_to_str(pdp_type_org, pdp_type, "Unknown PDP org"));
      proto_tree_add_text(ext_tree_pdp, tvb, offset+1, 1, "PDP type: %s", val_to_str(pdp_type_num, pdp_type, "Unknown PDP type"));
      proto_tree_add_text(ext_tree_pdp, tvb, offset+2, 1, "PDP address length: %u", pdp_addr_len);

      if (pdp_addr_len > 0) {
            switch (pdp_type_num) {
                  case 0x21:
                        addr_ipv4 = tvb_get_ipv4(tvb, offset+3);
                        proto_tree_add_text(ext_tree_pdp, tvb, offset+3, 4, "PDP address: %s", ip_to_str((guint8 *)&addr_ipv4));
                        break;
                  case 0x57:
                        tvb_get_ipv6(tvb, offset+3, &addr_ipv6);
                        proto_tree_add_text(ext_tree_pdp, tvb, offset+3, 16, "PDP address: %s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                        break;
                  default:
                        break;
            }
      }

      offset = offset + 3 + pdp_addr_len;

      ggsn_addr_len = tvb_get_guint8(tvb, offset);
      proto_tree_add_text(ext_tree_pdp, tvb, offset, 1, "GGSN address length: %u", ggsn_addr_len);

      switch (ggsn_addr_len) {
            case 4:
                  addr_ipv4 = tvb_get_ipv4(tvb, offset+1);
                  proto_tree_add_text(ext_tree_pdp, tvb, offset+1, 4, "GGSN address: %s", ip_to_str((guint8 *)&addr_ipv4));
                  break;
            case 16:
                  tvb_get_ipv6(tvb, offset+1, &addr_ipv6);
                  proto_tree_add_text(ext_tree_pdp, tvb, offset+1, 16, "GGSN address: %s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                  break;
            default:
                  break;
      }

      offset = offset + 1 + ggsn_addr_len;

      if (gtp_version == 1) {

            ggsn_addr_len = tvb_get_guint8(tvb, offset);
            proto_tree_add_text(ext_tree_pdp, tvb, offset, 1, "GGSN 2 address length: %u", ggsn_addr_len);

            switch (ggsn_addr_len) {
                  case 4:
                        addr_ipv4 = tvb_get_ipv4(tvb, offset+1);
                        proto_tree_add_text(ext_tree_pdp, tvb, offset+1, 4, "GGSN 2 address: %s", ip_to_str((guint8 *)&addr_ipv4));
                        break;
                  case 16:
                        tvb_get_ipv6(tvb, offset+1, &addr_ipv6);
                        proto_tree_add_text(ext_tree_pdp, tvb, offset+1, 16, "GGSN 2 address: %s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                        break;
                  default:
                        break;
            }
            offset = offset + 1 + ggsn_addr_len;

      }

      apn_len = tvb_get_guint8(tvb, offset);
      proto_tree_add_text(ext_tree_pdp, tvb, offset, 1, "APN length: %u", apn_len);
      decode_apn(tvb, offset+1, apn_len, ext_tree_pdp);

      offset = offset + 1 + apn_len;

      trans_id = tvb_get_guint8(tvb, offset);
      proto_tree_add_text(ext_tree_pdp, tvb, offset, 1, "Transaction identifier: %u", trans_id);

      return 3+length;
}

/* GPRS:    9.60, v7.6.0, chapter 7.9.21
 * UMTS:    29.060, v4.0, chapter 7.7.30
 */
static int
decode_gtp_apn(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree_apn;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_text (tree, tvb, offset, length+3, val_to_str(GTP_EXT_APN, gtp_val, "Unknown field"));
      ext_tree_apn = proto_item_add_subtree(te, ett_gtp_apn);

      proto_tree_add_text (ext_tree_apn, tvb, offset+1, 2, "APN length : %u", length);
      decode_apn (tvb, offset+3, length, ext_tree_apn);

      return 3+length;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.22
 *          4.08 v. 7.1.2, chapter 10.5.6.3 (p.580)
 * UMTS:    29.060 v4.0, chapter 7.7.31
 *          24.008, v4.2, chapter 10.5.6.3
 */
int
decode_gtp_proto_conf(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree) {

      guint16         length, proto_offset;
      guint16           proto_id;
      guint8          conf, proto_len, cnt = 1;
      tvbuff_t        *next_tvb;
      proto_tree      *ext_tree_proto;
      proto_item      *te;
      gboolean    save_writable;

      length = tvb_get_ntohs(tvb, offset + 1);

      te = proto_tree_add_text(tree, tvb, offset, length + 3, val_to_str(GTP_EXT_PROTO_CONF, gtp_val, "Unknown message"));
      ext_tree_proto = proto_item_add_subtree(te, ett_gtp_proto);

      proto_tree_add_text(ext_tree_proto, tvb, offset + 1, 2, "Length: %u", length);

      if (length < 1) return 3;

      conf = tvb_get_guint8 (tvb, offset + 3) & 0x07;
      proto_tree_add_text (ext_tree_proto, tvb, offset + 3, 1, "Configuration protocol (00000xxx): %u", conf);

      proto_offset = 1;       /* ... 1st byte is conf */
      offset += 4;

      for (;;) {
            if (proto_offset >= length) break;
            proto_id = tvb_get_ntohs (tvb, offset);
            proto_len = tvb_get_guint8 (tvb, offset + 2);
            proto_offset += proto_len + 3;            /* 3 = proto id + length byte */

            if (proto_len > 0) {

                  proto_tree_add_text (ext_tree_proto, tvb, offset, 2, "Protocol %u ID: %s (0x%04x)",
                      cnt, val_to_str(proto_id, ppp_vals, "Unknown"),
                      proto_id);
                  proto_tree_add_text (ext_tree_proto, tvb, offset+2, 1, "Protocol %u length: %u", cnt, proto_len);

                  /*
                   * Don't allow the dissector for the configuration
                   * protocol in question to update the columns - this
                   * is GTP, not PPP.
                   */
                  save_writable = col_get_writable(pinfo->cinfo);
                  col_set_writable(pinfo->cinfo, FALSE);

                  /*
                   * XXX - should we have our own dissector table,
                   * solely for configuration protocols, so that bogus
                   * values don't cause us to dissect the protocol
                   * data as, for example, IP?
                   */
                  next_tvb = tvb_new_subset (tvb, offset + 3, proto_len, proto_len);
                  if (!dissector_try_port(ppp_subdissector_table,
                      proto_id, next_tvb, pinfo, ext_tree_proto)) {
                        call_dissector(data_handle, next_tvb, pinfo,
                            ext_tree_proto);
                  }

                  col_set_writable(pinfo->cinfo, save_writable);
            }

            offset += proto_len + 3;
            cnt++;
      }

      return 3 + length;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.23
 * UMTS:    29.060 v4.0, chapter 7.7.32
 */
static int
decode_gtp_gsn_addr(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint8            addr_type, addr_len;
      guint16           length;
      guint32           addr_ipv4;
      struct      e_in6_addr addr_ipv6;
      proto_tree  *ext_tree_gsn_addr;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_text(tree, tvb, offset, 3+length, "GSN address : ");
      ext_tree_gsn_addr = proto_item_add_subtree(te, ett_gtp_gsn_addr);

      switch (length) {
            case 4:
                  proto_tree_add_text(ext_tree_gsn_addr, tvb, offset+1, 2, "GSN address length : %u", length);
                  addr_ipv4 = tvb_get_ipv4(tvb, offset+3);
                  proto_item_append_text(te, "%s", ip_to_str((guint8 *)&addr_ipv4));
                  proto_tree_add_ipv4(ext_tree_gsn_addr, hf_gtp_gsn_ipv4, tvb, offset+3, 4, addr_ipv4);
                  break;
            case 5:
                  proto_tree_add_text(ext_tree_gsn_addr, tvb, offset+1, 2, "GSN address Information Element length : %u", length);
                  addr_type = tvb_get_guint8(tvb, offset+3) & 0xC0;
                  proto_tree_add_uint(ext_tree_gsn_addr, hf_gtp_gsn_addr_type, tvb, offset+3, 1, addr_type);
                  addr_len = tvb_get_guint8(tvb, offset+3) & 0x3F;
                  proto_tree_add_uint(ext_tree_gsn_addr, hf_gtp_gsn_addr_len, tvb, offset+3, 1, addr_len);
                  addr_ipv4 = tvb_get_ipv4(tvb, offset+4);
                  proto_item_append_text(te, "%s", ip_to_str((guint8 *)&addr_ipv4));
                  proto_tree_add_ipv4(ext_tree_gsn_addr, hf_gtp_gsn_ipv4, tvb, offset+4, 4, addr_ipv4);
                  break;
            case 16:
                  proto_tree_add_text(ext_tree_gsn_addr, tvb, offset+1, 2, "GSN address length : %u", length);
                  tvb_get_ipv6(tvb, offset+3, &addr_ipv6);
                  proto_item_append_text(te, "%s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                  proto_tree_add_ipv6(ext_tree_gsn_addr, hf_gtp_gsn_ipv6, tvb, offset+3, 16, (guint8*)&addr_ipv6);
                  break;
            case 17:
                  proto_tree_add_text(ext_tree_gsn_addr, tvb, offset+1, 2, "GSN address Information Element length : %u", length);
                  addr_type = tvb_get_guint8(tvb, offset+3) & 0xC0;
                  proto_tree_add_uint(ext_tree_gsn_addr, hf_gtp_gsn_addr_type, tvb, offset+3, 1, addr_type);
                  addr_len = tvb_get_guint8(tvb, offset+3) & 0x3F;
                  proto_tree_add_uint(ext_tree_gsn_addr, hf_gtp_gsn_addr_len, tvb, offset+3, 1, addr_len);
                  tvb_get_ipv6(tvb, offset+4, &addr_ipv6);
                  proto_item_append_text(te, "%s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                  proto_tree_add_ipv6(ext_tree_gsn_addr, hf_gtp_gsn_ipv6, tvb, offset+4, 16, (guint8*)&addr_ipv6);
                  break;
            default:
                  proto_item_append_text(te, "unknown type or wrong length");
                  break;
      }

      return 3+length;
}

/* GPRS:    9.60 v7.6.0, chapter 7.9.24
 * UMTS:    29.060 v4.0, chapter 7.7.33
 */
static int
decode_gtp_msisdn(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      const guint8      *msisdn_val;
      gchar       *msisdn_str;
      guint16           length;

      length = tvb_get_ntohs(tvb, offset+1);

      if (length < 1) return 3;

      msisdn_val = tvb_get_ptr(tvb, offset+3, length);
      msisdn_str = msisdn_to_str(msisdn_val, length);

      proto_tree_add_string(tree, hf_gtp_msisdn, tvb, offset, 3+length, msisdn_str);

      return 3+length;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.34
 *          24.008 v4.2, chapter 10.5.6.5
 */
static int
decode_gtp_qos_umts(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      return decode_qos_umts(tvb, offset, tree, "Quality of Service", 2);
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.35
 */
static int
decode_gtp_auth_qui(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      proto_tree  *ext_tree_quint;
      proto_item  *te_quint;
      guint16           q_offset, q_len;
      guint8      xres_len, auth_len;

      q_offset = 0;


      offset = offset + q_offset;

      q_len = tvb_get_ntohs(tvb, offset);

      te_quint = proto_tree_add_text(tree, tvb, offset+1, q_len, "Quintuplet");
      ext_tree_quint = proto_item_add_subtree(te_quint, ett_gtp_quint);

      proto_tree_add_text(ext_tree_quint, tvb, offset, 2, "Length: %x", q_len);
      q_offset = q_offset + 2;

      proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 16, "RAND: %s", tvb_bytes_to_str(tvb, offset, 16));
      q_offset = q_offset + 16;
      xres_len = tvb_get_guint8(tvb, offset+q_offset);
      proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 1, "XRES length: %u", xres_len);
      q_offset++;
      proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, xres_len, "XRES: %s", tvb_bytes_to_str(tvb, offset + q_offset, xres_len));
      q_offset = q_offset + xres_len;
      proto_tree_add_text(ext_tree_quint, tvb ,offset + q_offset, 16, "Quintuplet Ciphering Key: %s", tvb_bytes_to_str(tvb, offset + q_offset, 16));
      q_offset = q_offset + 16;
      proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 16, "Quintuplet Integrity Key: %s", tvb_bytes_to_str(tvb, offset + q_offset, 16));
      q_offset = q_offset +16;
      auth_len = tvb_get_guint8(tvb, offset + q_offset);
      proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, 1, "Authentication length: %u", auth_len);
      q_offset++;
      proto_tree_add_text(ext_tree_quint, tvb, offset + q_offset, auth_len, "AUTH: %s", tvb_bytes_to_str(tvb, offset + q_offset, auth_len));

      q_offset = q_offset+auth_len;

      return (1 + q_offset);

}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.36
 *          24.008 v4.2, chapter 10.5.6.12
 */
static int
decode_gtp_tft(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, port1, port2, tos;
      guint8            tft_flags, tft_code, no_packet_filters, i, pf_id, pf_eval, pf_len, pf_content_id, proto, spare;
      guint       pf_offset;
      guint32           mask_ipv4, addr_ipv4, ipsec_id, label;
      struct      e_in6_addr addr_ipv6, mask_ipv6;
      proto_tree  *ext_tree_tft, *ext_tree_tft_pf, *ext_tree_tft_flags;
      proto_item  *te, *tee, *tef;

      length = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_text(tree, tvb, offset, 3+length, "Traffic flow template");
      ext_tree_tft = proto_item_add_subtree(te, ett_gtp_tft);

      tft_flags = tvb_get_guint8(tvb, offset+3);
      tft_code = (tft_flags >> 5) & 0x07;
      spare = (tft_flags >> 4) & 0x01;
      no_packet_filters = tft_flags & 0x0F;

      proto_tree_add_text(ext_tree_tft, tvb, offset+1, 2, "TFT length: %u", length);

      tef = proto_tree_add_text (ext_tree_tft, tvb, offset + 3, 1, "TFT flags");
      ext_tree_tft_flags = proto_item_add_subtree (tef, ett_gtp_tft_flags);
      proto_tree_add_uint (ext_tree_tft_flags, hf_gtp_tft_code, tvb, offset + 3, 1, tft_flags);
      proto_tree_add_uint (ext_tree_tft_flags, hf_gtp_tft_spare, tvb, offset + 3, 1, tft_flags);
      proto_tree_add_uint (ext_tree_tft_flags, hf_gtp_tft_number, tvb, offset + 3, 1, tft_flags);

      offset = offset + 4;

      for (i=0;i<no_packet_filters;i++) {

            pf_id = tvb_get_guint8(tvb, offset);

            tee = proto_tree_add_text (ext_tree_tft, tvb, offset, 1, "Packet filter id: %u", pf_id);
            ext_tree_tft_pf = proto_item_add_subtree (tee, ett_gtp_tft_pf);
            offset++;

            if (tft_code != 2) {

                  pf_eval = tvb_get_guint8(tvb, offset);
                  pf_len = tvb_get_guint8(tvb, offset + 1);

                  proto_tree_add_uint (ext_tree_tft_pf, hf_gtp_tft_eval, tvb, offset, 1, pf_eval);
                  proto_tree_add_text (ext_tree_tft_pf, tvb, offset+1, 1, "Content length: %u", pf_len);

                  offset = offset + 2;
                  pf_offset = 0;

                  while (pf_offset < pf_len) {

                        pf_content_id = tvb_get_guint8 (tvb, offset + pf_offset);

                        switch (pf_content_id) {
                              /* address IPv4 and mask = 8 bytes*/
                              case 0x10:
                                    addr_ipv4 = tvb_get_ipv4 (tvb, offset + pf_offset + 1);
                                    mask_ipv4 = tvb_get_ipv4 (tvb, offset + pf_offset + 5);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 9, "ID 0x10: IPv4/mask: %s/%s", ip_to_str ((guint8 *)&addr_ipv4), ip_to_str ((guint8 *)&mask_ipv4));
                                    pf_offset = pf_offset + 9;
                                    break;
                              /* address IPv6 and mask = 32 bytes*/
                              case 0x20:
                                    tvb_get_ipv6 (tvb, offset+pf_offset+1, &addr_ipv6);
                                    tvb_get_ipv6 (tvb, offset+pf_offset+17, &mask_ipv6);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset+pf_offset, 33, "ID 0x20: IPv6/mask: %s/%s", ip6_to_str ((struct e_in6_addr*)&addr_ipv6), ip6_to_str ((struct e_in6_addr*)&mask_ipv6));
                                    pf_offset = pf_offset + 33;
                                    break;
                              /* protocol identifier/next header type = 1 byte*/
                              case 0x30:
                                    proto = tvb_get_guint8 (tvb, offset + pf_offset + 1);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 2, "ID 0x30: IPv4 protocol identifier/IPv6 next header: %u (%x)", proto, proto);
                                    pf_offset = pf_offset + 2;
                                    break;
                              /* single destination port type = 2 bytes */
                              case 0x40:
                                    port1 = tvb_get_ntohs (tvb, offset + pf_offset + 1);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 3, "ID 0x40: destination port: %u", port1);
                                    pf_offset = pf_offset + 3;
                                    break;
                              /* destination port range type = 4 bytes */
                              case 0x41:
                                    port1 = tvb_get_ntohs (tvb, offset + pf_offset + 1);
                                    port2 = tvb_get_ntohs (tvb, offset + pf_offset + 3);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 5, "ID 0x41: destination port range: %u - %u", port1, port2);
                                    pf_offset = pf_offset + 5;
                                    break;
                              /* single source port type = 2 bytes */
                              case 0x50:
                                    port1 = tvb_get_ntohs (tvb, offset + pf_offset + 1);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 3, "ID 0x50: source port: %u", port1);
                                    pf_offset = pf_offset + 3;
                                    break;
                              /* source port range type = 4 bytes */
                              case 0x51:
                                    port1 = tvb_get_ntohs (tvb, offset + pf_offset + 1);
                                    port2 = tvb_get_ntohs (tvb, offset + pf_offset + 3);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 5, "ID 0x51: source port range: %u - %u", port1, port2);
                                    pf_offset = pf_offset + 5;
                                    break;
                              /* security parameter index type = 4 bytes */
                              case 0x60:
                                    ipsec_id = tvb_get_ntohl (tvb, offset + pf_offset + 1);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 5, "ID 0x60: security parameter index: %x", ipsec_id);
                                    pf_offset = pf_offset + 5;
                                    break;
                              /* type of service/traffic class type = 2 bytes */
                              case 0x70:
                                    tos = tvb_get_ntohs (tvb, offset + pf_offset + 1);
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 2, "ID 0x70: Type of Service/Traffic Class: %u (%x)", tos, tos);
                                    pf_offset = pf_offset + 3;
                                    break;
                              /* flow label type = 3 bytes */
                              case 0x80:
                                    label = tvb_get_ntoh24(tvb, offset + pf_offset + 1) & 0x0FFFFF;
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 4, "ID 0x80: Flow Label: %u (%x)", label, label);
                                    pf_offset = pf_offset + 4;
                                    break;

                              default:
                                    proto_tree_add_text (ext_tree_tft_pf, tvb, offset + pf_offset, 1, "Unknown value: %x ", pf_content_id);
                                    pf_offset++; /* to avoid infinite loop */
                                    break;
                        }
                  }

                  offset = offset + pf_offset;
            }
      }

      return 3 + length;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.37
 * Type = 138 (Decimal)
 *          25.413(RANAP) TargetID 
 */
static int
decode_gtp_target_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_item  *target_id_item;
      proto_tree  *ext_tree;
      tvbuff_t    *next_tvb;
      asn1_ctx_t asn1_ctx;
      asn1_ctx_init(&asn1_ctx, ASN1_ENC_PER, TRUE, pinfo);
      
      length = tvb_get_ntohs(tvb, offset + 1);

      target_id_item = proto_tree_add_text (tree, tvb, offset, 3 + length, "Target Identification");
      ext_tree = proto_item_add_subtree (target_id_item, ett_gtp_target_id);
      offset = offset +1;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      next_tvb = tvb_new_subset (tvb, offset, length, length);
      dissect_ranap_TargetID(next_tvb, 0, &asn1_ctx, ext_tree, hf_gtp_targetid);

      return 3 + length;
}


/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.38
 */
static int
decode_gtp_utran_cont(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_item  *utran_cont_item;
      proto_tree  *ext_tree;
      tvbuff_t    *next_tvb;

      length = tvb_get_ntohs(tvb, offset + 1);

      utran_cont_item = proto_tree_add_text(tree, tvb, offset, 3 + length, "UTRAN transparent field");
      ext_tree = proto_item_add_subtree (utran_cont_item, ett_gtp_utran_cont);
      offset = offset +1;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      next_tvb = tvb_new_subset (tvb, offset, length, length);

      return 3 + length;

}


/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.39
 */
static int
decode_gtp_rab_setup(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint32           teid, addr_ipv4;
      guint16           length;
      guint8            nsapi;
      struct      e_in6_addr addr_ipv6;
      proto_tree  *ext_tree_rab_setup;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset + 1);
      nsapi = tvb_get_guint8(tvb, offset + 3) & 0x0F;

      te = proto_tree_add_text(tree, tvb, offset, 3+length, "Radio Access Bearer Setup Information");
      ext_tree_rab_setup = proto_item_add_subtree(te, ett_gtp_rab_setup);

      proto_tree_add_text(ext_tree_rab_setup, tvb, offset+1, 2, "RAB setup length : %u", length);
      proto_tree_add_uint(ext_tree_rab_setup, hf_gtp_nsapi, tvb, offset+3, 1, nsapi);

      if (length > 1) {

            teid = tvb_get_ntohl(tvb, offset + 4);

            proto_tree_add_uint(ext_tree_rab_setup, hf_gtp_teid_data, tvb, offset+4, 4, teid);

            switch (length) {
                  case 12:
                        addr_ipv4 = tvb_get_ipv4(tvb, offset+8);
                        proto_tree_add_ipv4(ext_tree_rab_setup, hf_gtp_rnc_ipv4, tvb, offset+8, 4, addr_ipv4);
                        break;
                  case 24:
                        tvb_get_ipv6(tvb, offset+8, &addr_ipv6);
                        proto_tree_add_ipv6(ext_tree_rab_setup, hf_gtp_rnc_ipv6, tvb, offset+8, 16, (guint8 *)&addr_ipv6);
                        break;
                  default:
                        break;
            }
      }

      return 3 + length;
}


/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.40
 */
static int
decode_gtp_hdr_list(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      int         i;
      guint8            length, hdr;
      proto_tree  *ext_tree_hdr_list;
      proto_item  *te;

      length = tvb_get_guint8(tvb, offset + 1);

      te = proto_tree_add_text(tree, tvb, offset, 2+length, "%s", val_to_str(GTP_EXT_HDR_LIST, gtp_val, "Unknown"));
      ext_tree_hdr_list = proto_item_add_subtree(te, ett_gtp_hdr_list);

      proto_tree_add_text(ext_tree_hdr_list, tvb, offset+1, 1, "Number of Extension Header Types in list (i.e., length) : %u", length);

      for(i=0 ; i<length ; i++) {
            hdr = tvb_get_guint8(tvb, offset+2+i);

            proto_tree_add_text(ext_tree_hdr_list, tvb, offset+2+i, 1, "No. %u --> Extension Header Type value : %s (%u)", i+1, val_to_str(hdr, gtp_val, "Unknown Extension Header Type"), hdr);
      }

      return 2 + length;
}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.41
 * TODO:    find TriggerID description
 */
static int
decode_gtp_trigger_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;

      length = tvb_get_ntohs(tvb, offset + 1);

      proto_tree_add_text(tree, tvb, offset, 3+length, "%s length : %u", val_to_str(GTP_EXT_TRIGGER_ID, gtp_val, "Unknown"), length);

      return 3 + length;

}

/* GPRS:    not present
 * UMTS:    29.060 v4.0, chapter 7.7.42
 * TODO:    find OMC-ID description
 */
static int
decode_gtp_omc_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;

      length = tvb_get_ntohs(tvb, offset + 1);

      proto_tree_add_text(tree, tvb, offset, 3+length, "%s length : %u", val_to_str(GTP_EXT_OMC_ID, gtp_val, "Unknown"), length);

      return 3 + length;

}

/* GPRS:    9.60 v7.6.0, chapter 7.9.25
 * UMTS:    29.060 v6.11.0, chapter 7.7.44 Charging Gateway Address
 */
static int
decode_gtp_chrg_addr(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      guint32           addr_ipv4;
      struct      e_in6_addr addr_ipv6;
      proto_tree  *ext_tree_chrg_addr;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_CHRG_ADDR, gtp_val, "Unknown"));
      ext_tree_chrg_addr = proto_item_add_subtree(te, ett_gtp_chrg_addr);

      proto_tree_add_text(ext_tree_chrg_addr, tvb, offset+1, 2, "%s length : %u", val_to_str(GTP_EXT_CHRG_ADDR, gtp_val, "Unknown"), length);

      switch (length) {
            case 4:
                  addr_ipv4 = tvb_get_ipv4(tvb, offset+3);
                  proto_item_append_text(te, "%s", ip_to_str((guint8 *)&addr_ipv4));
                  proto_tree_add_ipv4 (ext_tree_chrg_addr, hf_gtp_chrg_ipv4, tvb, offset+3, 4, addr_ipv4);
                  break;
            case 16:
                  tvb_get_ipv6(tvb, offset+3, &addr_ipv6);
                  proto_item_append_text(te, "%s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                  proto_tree_add_ipv6 (ext_tree_chrg_addr, hf_gtp_chrg_ipv6, tvb, offset+3, 16, (guint8*)&addr_ipv6);
                  break;
            default:
                  proto_item_append_text(te, "unknown type or wrong length");
                  break;
      }

      return 3 + length;
}

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.44 RAN Transparent Container
 */
 static int
 decode_gtp_ran_tr_cont(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_RAN_TR_CONT, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_ran_tr_cont);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

  }
 
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.45 PDP Context Prioritization
 */
 static int
 decode_gtp_pdp_cont_prio(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_PDP_CONT_PRIO, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_pdp_cont_prio);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

  }
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.45A Additional RAB Setup Information
 */
static int
decode_gtp_add_rab_setup_inf(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_ADD_RAB_SETUP_INF, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_rab_setup_inf);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

  }
 

 /* GPRS:   ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.47 SGSN Number
 */
 static int
 decode_gtp_ssgn_no(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_SSGN_NO, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_ssgn_no);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

  }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.48 Common Flags
 */
 static int
 decode_gtp_common_flgs(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_COMMON_FLGS, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_common_flgs);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

  }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.49
 */
static int
decode_gtp_apn_res(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree_apn_res;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_APN_RES, gtp_val, "Unknown"));
      ext_tree_apn_res = proto_item_add_subtree(te, ett_gtp_ext_tree_apn_res);
      
      offset++;
      proto_tree_add_item(ext_tree_apn_res, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;

      /* Restriction Type value */
      proto_tree_add_item(ext_tree_apn_res, hf_gtp_ext_apn_res, tvb, offset, length, FALSE);
      return 3 + length;
}

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.50
 * RAT Type
 * Type = 151 (Decimal)
 */
static int
decode_gtp_rat_type(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree_rat_type;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_RAT_TYPE, gtp_val, "Unknown"));
      ext_tree_rat_type = proto_item_add_subtree(te, ett_gtp_ext_rat_type);
      
      offset++;
      proto_tree_add_item(ext_tree_rat_type, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;

      /* RAT Type value */
      proto_tree_add_item(ext_tree_rat_type, hf_gtp_ext_rat_type, tvb, offset, length, FALSE);
      
      return 3 + length;
}
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.51 
 * User Location Information
 * Type = 152 (Decimal)
 */
static int
decode_gtp_usr_loc_inf(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;
      guint8            geo_loc_type;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_USR_LOC_INF, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_usr_loc_inf);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      /* Geographic Location Type */
      proto_tree_add_item(ext_tree, hf_gtp_ext_geo_loc_type, tvb, offset, 1, FALSE);
      geo_loc_type = tvb_get_guint8(tvb,offset);
      offset++;
      
      if (geo_loc_type == 0)
            /* Use gsm_a's function to dissect Geographic Location by faking disc ( last 0) */
            be_cell_id_aux(tvb, ext_tree, offset, length-1, NULL, 0, 0);
      if (geo_loc_type == 1){
            /* Use gsm_a's function to dissect Geographic Location by faking disc ( last 4) */
            be_cell_id_aux(tvb, ext_tree, offset, length-1, NULL, 0, 4);
            offset = offset + 5;
            proto_tree_add_item(ext_tree, hf_gtp_ext_sac, tvb, offset, 2, FALSE);
      }

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.52 
 * MS Time Zone
 * Type = 153 (Decimal)
 */
static int
decode_gtp_ms_time_zone(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;
      /*guint8          data;*/
      /*char            sign;*/

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s : ", val_to_str(GTP_EXT_MS_TIME_ZONE, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_ms_time_zone);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;

      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");
      /* 3GPP TS 23.040 version 6.6.0 Release 6 
       * 9.2.3.11 TP-Service-Centre-Time-Stamp (TP-SCTS)
       * :
       * The Time Zone indicates the difference, expressed in quarters of an hour, 
       * between the local time and GMT. In the first of the two semi-octets, 
       * the first bit (bit 3 of the seventh octet of the TP-Service-Centre-Time-Stamp field)
       * represents the algebraic sign of this difference (0: positive, 1: negative).
       */
      /*
    data = tvb_get_guint8(tvb, offset);
    sign = (data & 0x08)?'-':'+';
    data = (data >> 4) + (data & 0x07) * 10;

    proto_tree_add_text(tree, tvb, offset, 1,"Timezone: GMT %c %d hours %d minutes",
            sign, data / 4, data % 4 * 15);

      */
      return 3 + length;

 }
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.53
 * International Mobile Equipment Identity (and Software Version) (IMEI(SV))
 * Type = 154 (Decimal)
 */
static int
decode_gtp_imeisv(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_imeisv;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_IMEISV, gtp_val, "Unknown"));
      ext_imeisv = proto_item_add_subtree(te, ett_gtp_ext_imeisv);
      
      offset++;
      proto_tree_add_item(ext_imeisv, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;

      /* IMEI(SV) */
      proto_tree_add_item(ext_imeisv, hf_gtp_ext_imeisv, tvb, offset, length, FALSE);
      
      return 3 + length;
}
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.54 
 * CAMEL Charging Information Container
 * Type = 155 (Decimal)
 */
static int
decode_gtp_camel_chg_inf_con(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_CAMEL_CHG_INF_CON, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_camel_chg_inf_con);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.55 
 * MBMS UE Context
 */
static int
decode_gtp_mbms_ue_ctx(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_UE_CTX, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_GTP_EXT_MBMS_UE_CTX);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.56
 * Temporary Mobile Group Identity (TMGI)
 */
static int
decode_gtp_tmgi(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_TMGI, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_tmgi);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;

      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.57
 * RIM Routing Address
 */
static int
decode_gtp_rim_ra(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_RIM_RA, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_rim_ra);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");
      /*  
       * Octets 4-n are coded according to 3GPP TS 48.018 [20] 11.3.77 RIM Routing Information IE octets 4-n.
       */

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.58
 * MBMS Protocol Configuration Options
 */
static int
decode_gtp_mbms_prot_conf_opt(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_PROT_CONF_OPT, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_mbms_prot_conf_opt);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }
/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.59
 * MBMS Session Duration
 */
static int
decode_gtp_mbms_ses_dur(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_SES_DUR, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_bms_ses_dur);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.60
 * MBMS Service Area
 */
static int
decode_gtp_mbms_sa(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_SA, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_mbms_sa);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.61
 * Source RNC PDCP context info
 */
static int
decode_gtp_src_rnc_pdp_ctx_inf(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_SRC_RNC_PDP_CTX_INF, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_src_rnc_pdp_ctx_inf);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.62 
 * Additional Trace Info
 */
static int
decode_gtp_add_trs_inf(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_ADD_TRS_INF, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_add_trs_inf);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.63 
 * Hop Counter
 */
static int
decode_gtp_hop_count(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_HOP_COUNT, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_hop_count);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.64 
 * Selected PLMN ID
 */
static int
decode_gtp_sel_plmn_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_SEL_PLMN_ID, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_sel_plmn_id);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.65
 * MBMS Session Identifier
 */
static int
decode_gtp_mbms_ses_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_SES_ID, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_mbms_ses_id);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.66
 * MBMS 2G/3G Indicator
 */
static int
decode_gtp_mbms_2g_3g_ind(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_2G_3G_IND, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_mbms_2g_3g_ind);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.67
 * Enhanced NSAPI
 */
static int
decode_gtp_enh_nsapi(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_ENH_NSAPI, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_enh_nsapi);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.68
 * Additional MBMS Trace Info
 */
static int
decode_gtp_add_mbms_trs_inf(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_ADD_MBMS_TRS_INF, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_ad_mbms_trs_inf);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.69
 * MBMS Session Identity Repetition Number
 */
static int
decode_gtp_mbms_ses_id_rep_no(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_SES_ID_REP_NO, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_mbms_ses_id_rep_no);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.70
 * MBMS Time To Data Transfer
 */
static int
decode_gtp_mbms_time_to_data_tr(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_MBMS_TIME_TO_DATA_TR, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_mbms_time_to_data_tr);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.71
 * PS Handover Request Context
 */
static int
decode_gtp_ps_ho_req_ctx(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_PS_HO_REQ_CTX, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_ps_ho_req_ctx);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.72
 * BSS Container
 */
static int
decode_gtp_bss_cont(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_BSS_CONT, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_bss_cont);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");
      /*
       * The content of this container is defined in 3GPP TS 48.018
       */

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.73
 * Cell Identification
 */
static int
decode_gtp_cell_id(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_CELL_ID, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_cell_id);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");
      /*
       * for PS handover from A/Gb mode, the identification of a target cell (Cell ID 1) and the identification of the
       * source cell (Cell ID 2) as defined in 3GPP TS 48.018 [20].
       *
       * for PS handover from Iu mode, the identification of a target cell (Cell ID 1)) and the identification of the
       * source RNC (RNC-ID) as defined in 3GPP TS 48.018
       */

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.74
 * PDU Numbers
 */
static int
decode_gtp_pdu_no(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_PDU_NO, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_pdu_no);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      /* TODO add decoding of data */
      proto_tree_add_text(ext_tree, tvb, offset, length, "Data not decoded yet");

      return 3 + length;

 }

/* GPRS:    ?
 * UMTS:    29.060 v6.11.0, chapter 7.7.75
 * BSSGP Cause
 */
static int
decode_gtp_bssgp_cause(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      proto_tree  *ext_tree;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);
      te = proto_tree_add_text(tree, tvb, offset, 3+length, "%s", val_to_str(GTP_EXT_BSSGP_CAUSE, gtp_val, "Unknown"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext_bssgp_cause);
      
      offset++;
      proto_tree_add_item(ext_tree, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset +2;
      
      /*    
       * The BSSGP Cause information element contains the cause as defined in 3GPP TS 48.018
       */
      proto_tree_add_item(ext_tree, hf_gtp_bssgp_cause, tvb, offset, 2, FALSE);

      return 3 + length;

 }

/* GPRS:    12.15
 * UMTS:    33.015
 */
static int
decode_gtp_rel_pack(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, n, number;
      proto_tree  *ext_tree_rel_pack;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset + 1);

      te = proto_tree_add_text(tree, tvb, offset, 3 + length, "Sequence numbers of released packets IE");
      ext_tree_rel_pack = proto_item_add_subtree(te, ett_gtp_rel_pack);

      n = 0;

      while (n < length) {

            number = tvb_get_ntohs(tvb, offset + 3 + n);
            proto_tree_add_text(ext_tree_rel_pack, tvb, offset + 3 + n, 2, "%u", number);
            n = n + 2;

      }

      return 3 + length;
}

/* GPRS:    12.15
 * UMTS:    33.015
 */
static int
decode_gtp_can_pack(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, n, number;
      proto_tree  *ext_tree_can_pack;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset + 1);

      te = proto_tree_add_text(tree, tvb, offset, 3 + length, "Sequence numbers of cancelled  packets IE");
      ext_tree_can_pack = proto_item_add_subtree(te, ett_gtp_can_pack);

      n = 0;

      while (n < length) {

            number = tvb_get_ntohs(tvb, offset + 3 + n);
            proto_tree_add_text(ext_tree_can_pack, tvb, offset + 3 + n, 2, "%u", number);
            n = n + 2;
      }

      return 3 + length;
}

/* CDRs dissector */
static int
decode_gtp_data_req(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, format_ver;
      guint8            no, format;
      proto_tree  *ext_tree;
      proto_item  *te;
      tvbuff_t    *next_tvb;

      te = proto_tree_add_text(tree, tvb, offset, 1, val_to_str(GTP_EXT_DATA_REQ, gtp_val, "Unknown message"));
      ext_tree = proto_item_add_subtree(te, ett_gtp_ext);

      length = tvb_get_ntohs(tvb, offset + 1);
      no = tvb_get_guint8(tvb, offset + 3);
      format = tvb_get_guint8(tvb, offset + 4);
      format_ver = tvb_get_ntohs(tvb, offset + 5);

      proto_tree_add_text(ext_tree, tvb, offset+1, 2, "Length: %u", length);
      proto_tree_add_text(ext_tree, tvb, offset+3, 1, "Number of data records: %u", no);
      proto_tree_add_text(ext_tree, tvb, offset+4, 1, "Data record format: %u", format);
      proto_tree_add_text(ext_tree, tvb, offset+5, 2, "Data record format version: %u", format_ver);

      if (gtpcdr_handle) {
            next_tvb = tvb_new_subset (tvb, offset, -1, -1);
            call_dissector (gtpcdr_handle, next_tvb, pinfo, tree);
      }
      else
            proto_tree_add_text (tree, tvb, offset, 0, "Data");

      return 3+length;
}

/* GPRS:    12.15
 * UMTS:    33.015
 */
static int
decode_gtp_data_resp(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, n, number;
      proto_tree  *ext_tree_data_resp;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset + 1);

      te = proto_tree_add_text(tree, tvb, offset, 3 + length, "Requests responded");
      ext_tree_data_resp = proto_item_add_subtree(te, ett_gtp_data_resp);

      n = 0;

      while (n < length) {

            number = tvb_get_ntohs(tvb, offset + 3 + n);
            proto_tree_add_text(ext_tree_data_resp, tvb, offset + 3 + n, 2, "%u", number);
            n = n + 2;

      }

      return 3 + length;

}

/* GPRS:    12.15
 * UMTS:    33.015
 */
static int
decode_gtp_node_addr(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length;
      guint32           addr_ipv4;
      struct      e_in6_addr addr_ipv6;
      proto_tree  *ext_tree_node_addr;
      proto_item  *te;

      length = tvb_get_ntohs(tvb, offset+1);

      te = proto_tree_add_text(tree, tvb, offset, 3+length, "Node address: ");
      ext_tree_node_addr = proto_item_add_subtree(te, ett_gtp_node_addr);

      proto_tree_add_text (ext_tree_node_addr, tvb, offset+1, 2, "Node address length: %u", length);

      switch (length) {
            case 4:
                  addr_ipv4 = tvb_get_ipv4(tvb, offset+3);
                  proto_item_append_text(te, "%s", ip_to_str((guint8 *)&addr_ipv4));
                  proto_tree_add_ipv4 (ext_tree_node_addr, hf_gtp_node_ipv4, tvb, offset+3, 4, addr_ipv4);
                  break;
            case 16:
                  tvb_get_ipv6(tvb, offset+3, &addr_ipv6);
                  proto_item_append_text(te, "%s", ip6_to_str((struct e_in6_addr*)&addr_ipv6));
                  proto_tree_add_ipv6 (ext_tree_node_addr, hf_gtp_node_ipv6, tvb, offset+3, 16, (guint8*)&addr_ipv6);
                  break;
            default:
                  proto_item_append_text(te, "unknown type or wrong length");
                  break;
      }

      return 3 + length;

}

/* GPRS:    9.60 v7.6.0, chapter 7.9.26
 * UMTS:    29.060 v4.0, chapter 7.7.46 Private Extension
 * 
 */

static int
decode_gtp_priv_ext(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      guint16           length, ext_id;
      proto_tree  *ext_tree_priv_ext;
      proto_item  *te;

      te = proto_tree_add_text(tree, tvb, offset, 1, val_to_str(GTP_EXT_PRIV_EXT, gtp_val, "Unknown message"));
      ext_tree_priv_ext = proto_item_add_subtree(te, ett_gtp_ext);

      offset++;
      length = tvb_get_ntohs(tvb, offset);
      proto_tree_add_item(ext_tree_priv_ext, hf_gtp_ext_length, tvb, offset, 2, FALSE);
      offset = offset+2;
      if (length >= 2) {
            ext_id = tvb_get_ntohs(tvb, offset);
            proto_tree_add_uint(ext_tree_priv_ext, hf_gtp_ext_id, tvb, offset, 2, ext_id);
            offset = offset+2;

            /*
             * XXX - is this always a text string?  Or should it be
             * displayed as hex data?
             */
            if (length > 2)
                  proto_tree_add_item(ext_tree_priv_ext, hf_gtp_ext_val, tvb, offset, length-2, FALSE);
      }

      return 3+length;
}

static int
decode_gtp_unknown(tvbuff_t *tvb, int offset, packet_info *pinfo _U_, proto_tree *tree) {

      proto_tree_add_text(tree, tvb, offset, 1, "Unknown extension header");

      return tvb_length_remaining(tvb, offset);
}

static void
dissect_gtp (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
      struct _gtp_hdr   gtp_hdr;
      proto_tree  *gtp_tree, *flags_tree;
      proto_item  *ti, *tf;
      int         i, offset, length, gtp_prime, checked_field, mandatory;
      int         seq_no, flow_label;
      guint8            pdu_no, next_hdr = 0, ext_hdr_val;
      const guint8      *tid_val;
      gchar       *tid_str;
      guint32           teid;
      tvbuff_t    *next_tvb;
      guint8            sub_proto, acfield_len = 0, control_field;

      if (check_col(pinfo->cinfo, COL_PROTOCOL))
            col_set_str(pinfo->cinfo, COL_PROTOCOL, "GTP");
      if (check_col(pinfo->cinfo, COL_INFO))
            col_clear(pinfo->cinfo, COL_INFO);

      tvb_memcpy(tvb, (guint8 *)&gtp_hdr, 0, 4);

      if (!(gtp_hdr.flags & 0x10))
            gtp_prime = 1;
      else
            gtp_prime = 0;

      switch ((gtp_hdr.flags >> 5) & 0x07) {
            case 0:
                  gtp_version = 0;
                  break;
            case 1:
                  gtp_version = 1;
                  break;
            default:
                  gtp_version = 1;
                  break;
      }

      if (check_col(pinfo->cinfo, COL_INFO))
            col_add_str(pinfo->cinfo, COL_INFO, val_to_str(gtp_hdr.message, message_type, "Unknown"));

      if (tree) {
            ti = proto_tree_add_item (tree, proto_gtp, tvb, 0, -1, FALSE);
            gtp_tree = proto_item_add_subtree(ti, ett_gtp);

            tf = proto_tree_add_uint (gtp_tree, hf_gtp_flags, tvb, 0, 1, gtp_hdr.flags);
            flags_tree = proto_item_add_subtree (tf, ett_gtp_flags);

            proto_tree_add_uint (flags_tree, hf_gtp_flags_ver, tvb, 0, 1, gtp_hdr.flags);
            proto_tree_add_uint (flags_tree, hf_gtp_flags_pt, tvb, 0, 1, gtp_hdr.flags);

            switch (gtp_version) {
                  case 0:
                        proto_tree_add_uint (flags_tree, hf_gtp_flags_spare1, tvb, 0, 1, gtp_hdr.flags);
                        proto_tree_add_boolean (flags_tree, hf_gtp_flags_snn, tvb, 0, 1, gtp_hdr.flags);
                        break;
                  case 1:
                        proto_tree_add_uint (flags_tree, hf_gtp_flags_spare2, tvb, 0, 1, gtp_hdr.flags);
                        proto_tree_add_boolean (flags_tree, hf_gtp_flags_e, tvb, 0, 1, gtp_hdr.flags);
                        proto_tree_add_boolean (flags_tree, hf_gtp_flags_s, tvb, 0, 1, gtp_hdr.flags);
                        proto_tree_add_boolean (flags_tree, hf_gtp_flags_pn, tvb, 0, 1, gtp_hdr.flags);
                        break;
                  default:
                        break;
            }

            proto_tree_add_uint (gtp_tree, hf_gtp_message_type, tvb, 1, 1, gtp_hdr.message);

            gtp_hdr.length = g_ntohs (gtp_hdr.length);
            proto_tree_add_uint (gtp_tree, hf_gtp_length, tvb, 2, 2, gtp_hdr.length);

            offset = 4;

            if (gtp_prime) {
                  seq_no = tvb_get_ntohs (tvb, offset);
                  proto_tree_add_uint (gtp_tree, hf_gtp_seq_number, tvb, offset, 2, seq_no);
                  offset += 2;
            } else
            switch (gtp_version) {
                  case 0:
                        seq_no = tvb_get_ntohs (tvb, offset);
                        proto_tree_add_uint (gtp_tree, hf_gtp_seq_number, tvb, offset, 2, seq_no);
                        offset += 2;

                        flow_label = tvb_get_ntohs (tvb, offset);
                        proto_tree_add_uint (gtp_tree, hf_gtp_flow_label, tvb, offset, 2, flow_label);
                        offset += 2;

                        pdu_no = tvb_get_guint8 (tvb, offset);
                        proto_tree_add_uint (gtp_tree, hf_gtp_sndcp_number, tvb, offset, 1, pdu_no);
                        offset += 4;

                        tid_val = tvb_get_ptr(tvb, offset, 8);
                        tid_str = id_to_str (tid_val);
                        proto_tree_add_string (gtp_tree, hf_gtp_tid, tvb, offset, 8, tid_str);
                        offset += 8;
                        break;
                  case 1:
                        teid = tvb_get_ntohl (tvb, offset);
                        proto_tree_add_uint (gtp_tree, hf_gtp_teid, tvb, offset, 4, teid);
                        offset += 4;

                        if (gtp_hdr.flags & 0x07) {
                              seq_no = tvb_get_ntohs (tvb, offset);
                              proto_tree_add_uint (gtp_tree, hf_gtp_seq_number, tvb, offset, 2, seq_no);
                              offset += 2;

                              pdu_no = tvb_get_guint8 (tvb, offset);
                              proto_tree_add_uint (gtp_tree, hf_gtp_npdu_number, tvb, offset, 1, pdu_no);
                              offset++;

                              next_hdr = tvb_get_guint8 (tvb, offset);
                              proto_tree_add_uint (gtp_tree, hf_gtp_next, tvb, offset, 1, next_hdr);
                              if (!next_hdr)
                                    offset++;
                        }
                        break;
                  default:
                        break;
            }


            if (gtp_hdr.message != GTP_MSG_TPDU) {
                  proto_tree_add_text(gtp_tree, tvb, 0, 0, "[--- end of GTP header, beginning of extension headers ---]");
                  length = tvb_length (tvb);
                  mandatory = 0;          /* check order of GTP fields against ETSI */
                  for (;;) {
                        if (offset >= length)
                              break;
                        if (next_hdr) {
                              ext_hdr_val = next_hdr;
                              next_hdr = 0;
                        }
                        else
                              ext_hdr_val = tvb_get_guint8 (tvb, offset);
                        if (gtp_etsi_order) {
                              checked_field = check_field_presence (gtp_hdr.message, ext_hdr_val , (int *)&mandatory);
                              switch (checked_field) {
                                    case -2: proto_tree_add_text (gtp_tree, tvb, 0, 0, "[WARNING] message not found");
                                           break;
                                    case -1: proto_tree_add_text (gtp_tree, tvb, 0, 0, "[WARNING] field not present");
                                           break;
                                    case 0:  break;
                                    default: proto_tree_add_text (gtp_tree, tvb, offset, 1, "[WARNING] wrong next field, should be: %s", val_to_str(checked_field, gtp_val, "Unknown extension field"));
                                           break;
                              }
                        }

                        i = -1;
                        while (gtpopt[++i].optcode)
                              if (gtpopt[i].optcode == ext_hdr_val)
                                    break;
                        offset = offset + (*gtpopt[i].decode)(tvb, offset, pinfo, gtp_tree);
                  }
            }
      }

      if ((gtp_hdr.message == GTP_MSG_TPDU) && gtp_tpdu) {

            if (gtp_prime)
                  offset = 6;
            else
            if (gtp_version == 1) {
                  if (gtp_hdr.flags & 0x07)  {
                        offset = 11;
                        if (tvb_get_guint8 (tvb, offset) == 0)
                              offset++;
                  }
                  else
                        offset = 8;
            }
            else
                  offset = 20;

            sub_proto = tvb_get_guint8 (tvb, offset);

            if ((sub_proto >= 0x45) &&  (sub_proto <= 0x4e)) {
                  /* this is most likely an IPv4 packet
                   * we can exclude 0x40 - 0x44 because the minimum header size is 20 octets
                   * 0x4f is excluded because PPP protocol type "IPv6 header compression"
                   * with protocol field compression is more likely than a plain IPv4 packet with 60 octet header size */

                  next_tvb = tvb_new_subset (tvb, offset, -1, -1);
                  call_dissector(ip_handle, next_tvb, pinfo, tree);

            } else
                if ((sub_proto & 0xf0) == 0x60){
                  /* this is most likely an IPv6 packet */
                  next_tvb = tvb_new_subset (tvb, offset, -1, -1);
                  call_dissector (ipv6_handle, next_tvb, pinfo, tree);
            } else {
                  /* this seems to be a PPP packet */

                  if (sub_proto == 0xff) {
                        /* this might be an address field, even it shouldn't be here */
                        control_field = tvb_get_guint8 (tvb, offset + 1);
                        if (control_field == 0x03)
                              /* now we are pretty sure that address and control field are mistakenly inserted -> ignore it for PPP dissection */
                              acfield_len = 2;
                  }

                  next_tvb = tvb_new_subset (tvb, offset + acfield_len, -1, -1);
                  call_dissector (ppp_handle, next_tvb, pinfo, tree);
            }

            if (check_col(pinfo->cinfo, COL_PROTOCOL))
                  col_append_str_gtp(pinfo->cinfo, COL_PROTOCOL, "GTP");
      }
}

static const true_false_string yes_no_tfs = {
      "yes" ,
      "no"
};

void
proto_register_gtp(void)
{
      static hf_register_info hf_gtp[] = {
            { &hf_gtp_apn, { "APN", "gtp.apn", FT_STRING, BASE_DEC, NULL, 0, "Access Point Name", HFILL }},
            { &hf_gtp_cause, { "Cause ", "gtp.cause", FT_UINT8, BASE_DEC, VALS(cause_type), 0, "Cause of operation", HFILL }},
            { &hf_gtp_chrg_char, { "Charging characteristics", "gtp.chrg_char", FT_UINT16, BASE_DEC, NULL, 0, "Charging characteristics", HFILL }},
            { &hf_gtp_chrg_char_s, { "Spare", "gtp.chrg_char_s", FT_UINT16,   BASE_DEC, NULL, GTP_MASK_CHRG_CHAR_S, "Spare", HFILL }},
            { &hf_gtp_chrg_char_n, { "Normal charging", "gtp.chrg_char_n", FT_UINT16, BASE_DEC, NULL, GTP_MASK_CHRG_CHAR_N, "Normal charging", HFILL }},
            { &hf_gtp_chrg_char_p, { "Prepaid charging", "gtp.chrg_char_p", FT_UINT16, BASE_DEC, NULL, GTP_MASK_CHRG_CHAR_P, "Prepaid charging", HFILL }},
            { &hf_gtp_chrg_char_f, { "Flat rate charging", "gtp.chrg_char_f", FT_UINT16, BASE_DEC, NULL, GTP_MASK_CHRG_CHAR_F, "Flat rate charging", HFILL }},
            { &hf_gtp_chrg_char_h, { "Hot billing charging", "gtp.chrg_char_h", FT_UINT16, BASE_DEC, NULL, GTP_MASK_CHRG_CHAR_H, "Hot billing charging", HFILL }},
            { &hf_gtp_chrg_char_r, { "Reserved", "gtp.chrg_char_r", FT_UINT16, BASE_DEC, NULL, GTP_MASK_CHRG_CHAR_R, "Reserved", HFILL }},
            { &hf_gtp_chrg_id, { "Charging ID", "gtp.chrg_id", FT_UINT32, BASE_HEX, NULL, 0, "Charging ID", HFILL }},
            { &hf_gtp_chrg_ipv4, { "CG address IPv4", "gtp.chrg_ipv4", FT_IPv4, BASE_DEC, NULL, 0, "Charging Gateway address IPv4", HFILL }},
            { &hf_gtp_chrg_ipv6, { "CG address IPv6", "gtp.chrg_ipv6", FT_IPv6, BASE_HEX, NULL, 0, "Charging Gateway address IPv6", HFILL }},
            { &hf_gtp_ext_flow_label, { "Flow Label Data I", "gtp.ext_flow_label", FT_UINT16, BASE_HEX, NULL, 0, "Flow label data", HFILL }},
            { &hf_gtp_ext_id, { "Extension identifier", "gtp.ext_id", FT_UINT16, BASE_DEC, VALS(sminmpec_values), 0, "Extension Identifier", HFILL }},
            { &hf_gtp_ext_val, { "Extension value", "gtp.ext_val", FT_BYTES, BASE_HEX, NULL, 0, "Extension Value", HFILL }},
            { &hf_gtp_flags, { "Flags", "gtp.flags", FT_UINT8, BASE_HEX, NULL, 0, "Ver/PT/Spare...", HFILL }},
            { &hf_gtp_flags_ver,
                  { "Version", "gtp.flags.version",
                  FT_UINT8, BASE_DEC, VALS(ver_types), GTP_VER_MASK,
                  "GTP Version", HFILL }
            },
            { &hf_gtp_flags_pt,
                  { "Protocol type",      "gtp.flags.payload",
                  FT_UINT8, BASE_DEC, VALS(pt_types), GTP_PT_MASK,
                  "Protocol Type", HFILL }
            },
            { &hf_gtp_flags_spare1,
                  { "Reserved", "gtp.flags.reserved",
                  FT_UINT8, BASE_DEC, NULL, GTP_SPARE1_MASK,
                  "Reserved (shall be sent as '111' )", HFILL }
            },
            { &hf_gtp_flags_snn, { "Is SNDCP N-PDU included?", "gtp.flags.snn", FT_BOOLEAN, 8, TFS(&yes_no_tfs), GTP_SNN_MASK, "Is SNDCP N-PDU LLC Number included? (1 = yes, 0 = no)", HFILL }},
            { &hf_gtp_flags_spare2, { "Reserved", "gtp.flags.reserved", FT_UINT8, BASE_DEC, NULL, GTP_SPARE2_MASK, "Reserved (shall be sent as '1' )", HFILL }},
            { &hf_gtp_flags_e, { "Is Next Extension Header present?", "gtp.flags.e", FT_BOOLEAN, 8, TFS(&yes_no_tfs), GTP_E_MASK, "Is Next Extension Header present? (1 = yes, 0 = no)", HFILL }},
            { &hf_gtp_flags_s, { "Is Sequence Number present?", "gtp.flags.s", FT_BOOLEAN, 8, TFS(&yes_no_tfs), GTP_S_MASK, "Is Sequence Number present? (1 = yes, 0 = no)", HFILL }},
            { &hf_gtp_flags_pn, { "Is N-PDU number present?", "gtp.flags.pn", FT_BOOLEAN, 8, TFS(&yes_no_tfs), GTP_PN_MASK, "Is N-PDU number present? (1 = yes, 0 = no)", HFILL }},
            { &hf_gtp_flow_ii, { "Flow Label Data II ", "gtp.flow_ii", FT_UINT16, BASE_DEC, NULL, 0, "Downlink flow label data", HFILL }},
            { &hf_gtp_flow_label, { "Flow label", "gtp.flow_label", FT_UINT16, BASE_HEX, NULL, 0, "Flow label", HFILL }},
            { &hf_gtp_flow_sig, { "Flow label Signalling", "gtp.flow_sig", FT_UINT16, BASE_HEX, NULL, 0, "Flow label signalling", HFILL }},
            { &hf_gtp_gsn_addr_len, { "GSN Address Length", "gtp.gsn_addr_len", FT_UINT8, BASE_DEC, NULL, GTP_EXT_GSN_ADDR_LEN_MASK, "GSN Address Length", HFILL }},
            { &hf_gtp_gsn_addr_type, { "GSN Address Type", "gtp.gsn_addr_type", FT_UINT8, BASE_DEC, VALS(gsn_addr_type), GTP_EXT_GSN_ADDR_TYPE_MASK, "GSN Address Type", HFILL }},
            { &hf_gtp_gsn_ipv4, { "GSN address IPv4", "gtp.gsn_ipv4", FT_IPv4, BASE_DEC, NULL, 0, "GSN address IPv4", HFILL }},
            { &hf_gtp_gsn_ipv6, { "GSN address IPv6", "gtp.gsn_ipv6", FT_IPv6, BASE_DEC, NULL, 0, "GSN address IPv6", HFILL }},
            { &hf_gtp_imsi, { "IMSI", "gtp.imsi", FT_STRING, BASE_DEC, NULL, 0, "International Mobile Subscriber Identity number", HFILL }},
            { &hf_gtp_length, { "Length", "gtp.length", FT_UINT16, BASE_DEC, NULL, 0, "Length (i.e. number of octets after TID or TEID)", HFILL }},
            { &hf_gtp_map_cause, { "MAP cause", "gtp.map_cause", FT_UINT8, BASE_DEC, VALS(gsm_map_LocalErrorcode_vals), 0, "MAP cause", HFILL }},
            { &hf_gtp_message_type, { "Message Type", "gtp.message", FT_UINT8, BASE_HEX, VALS(message_type), 0x0, "GTP Message Type", HFILL }},
            { &hf_gtp_ms_reason, { "MS not reachable reason", "gtp.ms_reason", FT_UINT8, BASE_DEC, VALS(ms_not_reachable_type), 0, "MS Not Reachable Reason", HFILL }},
            { &hf_gtp_ms_valid, { "MS validated", "gtp.ms_valid", FT_BOOLEAN, BASE_NONE,NULL, 0, "MS validated", HFILL }},
            { &hf_gtp_msisdn, { "MSISDN", "gtp.msisdn", FT_STRING, BASE_DEC, NULL, 0, "MS international PSTN/ISDN number", HFILL }},
            { &hf_gtp_next, { "Next extension header type", "gtp.next", FT_UINT8, BASE_HEX, NULL, 0, "Next Extension Header Type", HFILL }},
            { &hf_gtp_node_ipv4, { "Node address IPv4", "gtp.node_ipv4", FT_IPv4, BASE_DEC, NULL, 0, "Recommended node address IPv4", HFILL }},
            { &hf_gtp_node_ipv6, { "Node address IPv6", "gtp.node_ipv6", FT_IPv6, BASE_HEX, NULL, 0, "Recommended node address IPv6", HFILL }},
            { &hf_gtp_npdu_number, { "N-PDU Number", "gtp.npdu_number", FT_UINT8, BASE_HEX, NULL, 0, "N-PDU Number", HFILL }},
            { &hf_gtp_nsapi, { "NSAPI", "gtp.nsapi", FT_UINT8, BASE_DEC, NULL, 0, "Network layer Service Access Point Identifier", HFILL }},
            { &hf_gtp_qos_version, { "Version", "gtp.qos_version", FT_STRING, BASE_DEC, NULL, 0, "Version of the QoS Profile", HFILL }},
            { &hf_gtp_qos_spare1, { "Spare", "gtp.qos_spare1", FT_UINT8, BASE_DEC, NULL, GTP_EXT_QOS_SPARE1_MASK, "Spare (shall be sent as '00' )", HFILL }},
            { &hf_gtp_qos_delay, { "QoS delay", "gtp.qos_delay", FT_UINT8, BASE_DEC, VALS(qos_delay_type), GTP_EXT_QOS_DELAY_MASK, "Quality of Service Delay Class", HFILL }},
            { &hf_gtp_qos_reliability, { "QoS reliability", "gtp.qos_reliabilty", FT_UINT8, BASE_DEC, VALS(qos_reliability_type), GTP_EXT_QOS_RELIABILITY_MASK, "Quality of Service Reliability Class", HFILL }},
            { &hf_gtp_qos_peak, { "QoS peak", "gtp.qos_peak", FT_UINT8, BASE_DEC, VALS(qos_peak_type), GTP_EXT_QOS_PEAK_MASK, "Quality of Service Peak Throughput", HFILL }},
            { &hf_gtp_qos_spare2, { "Spare", "gtp.qos_spare2",FT_UINT8, BASE_DEC, NULL, GTP_EXT_QOS_SPARE2_MASK, "Spare (shall be sent as 0)", HFILL }},
            { &hf_gtp_qos_precedence, { "QoS precedence", "gtp.qos_precedence", FT_UINT8, BASE_DEC, VALS(qos_precedence_type), GTP_EXT_QOS_PRECEDENCE_MASK, "Quality of Service Precedence Class", HFILL }},
            { &hf_gtp_qos_spare3, { "Spare", "gtp.qos_spare3", FT_UINT8, BASE_DEC, NULL, GTP_EXT_QOS_SPARE3_MASK, "Spare (shall be sent as '000' )", HFILL }},
            { &hf_gtp_qos_mean, { "QoS mean", "gtp.qos_mean", FT_UINT8, BASE_DEC, VALS(qos_mean_type), GTP_EXT_QOS_MEAN_MASK, "Quality of Service Mean Throughput", HFILL }},
            { &hf_gtp_qos_al_ret_priority, { "Allocation/Retention priority ","gtp.qos_al_ret_priority", FT_UINT8, BASE_DEC, NULL, 0, "Allocation/Retention Priority", HFILL }},
            { &hf_gtp_qos_traf_class, { "Traffic class", "gtp.qos_traf_class", FT_UINT8, BASE_DEC, VALS(qos_traf_class), GTP_EXT_QOS_TRAF_CLASS_MASK, "Traffic Class", HFILL }},
            { &hf_gtp_qos_del_order, { "Delivery order", "gtp.qos_del_order", FT_UINT8, BASE_DEC, VALS(qos_del_order), GTP_EXT_QOS_DEL_ORDER_MASK, "Delivery Order", HFILL }},
            { &hf_gtp_qos_del_err_sdu, { "Delivery of erroneous SDU", "gtp.qos_del_err_sdu", FT_UINT8, BASE_DEC, VALS(qos_del_err_sdu), GTP_EXT_QOS_DEL_ERR_SDU_MASK, "Delivery of Erroneous SDU", HFILL }},
            { &hf_gtp_qos_max_sdu_size, { "Maximum SDU size", "gtp.qos_max_sdu_size", FT_UINT8, BASE_DEC, VALS(qos_max_sdu_size), 0, "Maximum SDU size", HFILL }},
            { &hf_gtp_qos_max_ul, { "Maximum bit rate for uplink",      "gtp.qos_max_ul", FT_UINT8, BASE_DEC, VALS(qos_max_ul), 0, "Maximum bit rate for uplink", HFILL }},
            { &hf_gtp_qos_max_dl, { "Maximum bit rate for downlink", "gtp.qos_max_dl", FT_UINT8, BASE_DEC, VALS(qos_max_dl), 0, "Maximum bit rate for downlink", HFILL }},
            { &hf_gtp_qos_res_ber, { "Residual BER", "gtp.qos_res_ber", FT_UINT8, BASE_DEC, VALS(qos_res_ber), GTP_EXT_QOS_RES_BER_MASK, "Residual Bit Error Rate", HFILL }},
            { &hf_gtp_qos_sdu_err_ratio, { "SDU Error ratio", "gtp.qos_sdu_err_ratio", FT_UINT8, BASE_DEC, VALS(qos_sdu_err_ratio), GTP_EXT_QOS_SDU_ERR_RATIO_MASK, "SDU Error Ratio", HFILL }},
            { &hf_gtp_qos_trans_delay, { "Transfer delay",  "gtp.qos_trans_delay", FT_UINT8, BASE_DEC, VALS(qos_trans_delay), GTP_EXT_QOS_TRANS_DELAY_MASK, "Transfer Delay", HFILL }},
            { &hf_gtp_qos_traf_handl_prio, { "Traffic handling priority", "gtp.qos_traf_handl_prio", FT_UINT8, BASE_DEC, VALS(qos_traf_handl_prio), GTP_EXT_QOS_TRAF_HANDL_PRIORITY_MASK, "Traffic Handling Priority", HFILL }},
            { &hf_gtp_qos_guar_ul, { "Guaranteed bit rate for uplink", "gtp.qos_guar_ul", FT_UINT8,   BASE_DEC, VALS(qos_guar_ul), 0, "Guaranteed bit rate for uplink", HFILL }},
            { &hf_gtp_qos_guar_dl, { "Guaranteed bit rate for downlink", "gtp.qos_guar_dl",     FT_UINT8, BASE_DEC, VALS(qos_guar_dl), 0, "Guaranteed bit rate for downlink", HFILL }},
            { &hf_gtp_pkt_flow_id, { "Packet Flow ID", "gtp.pkt_flow_id", FT_UINT8, BASE_DEC, NULL, 0, "Packet Flow ID", HFILL }},
            { &hf_gtp_ptmsi, { "P-TMSI", "gtp.ptmsi", FT_UINT32, BASE_HEX, NULL, 0, "Packet-Temporary Mobile Subscriber Identity", HFILL }},
            { &hf_gtp_ptmsi_sig, { "P-TMSI Signature", "gtp.ptmsi_sig", FT_UINT24, BASE_HEX, NULL, 0, "P-TMSI Signature", HFILL }},
            { &hf_gtp_rab_gtpu_dn, { "Downlink GTP-U seq number", "gtp.rab_gtp_dn", FT_UINT16, BASE_DEC, NULL, 0, "Downlink GTP-U sequence number", HFILL }},
            { &hf_gtp_rab_gtpu_up, { "Uplink GTP-U seq number", "gtp.rab_gtp_up", FT_UINT16, BASE_DEC, NULL, 0, "Uplink GTP-U sequence number", HFILL }},
            { &hf_gtp_rab_pdu_dn, { "Downlink next PDCP-PDU seq number", "gtp.rab_pdu_dn", FT_UINT16, BASE_DEC, NULL, 0, "Downlink next PDCP-PDU sequence number", HFILL }},
            { &hf_gtp_rab_pdu_up, { "Uplink next PDCP-PDU seq number", "gtp.rab_pdu_up", FT_UINT16, BASE_DEC, NULL, 0, "Uplink next PDCP-PDU sequence number", HFILL }},
            { &hf_gtp_rai_mcc, { "MCC", "gtp.mcc", FT_UINT16, BASE_DEC, NULL, 0, "Mobile Country Code", HFILL }},
            { &hf_gtp_rai_mnc, { "MNC", "gtp.mnc", FT_UINT8, BASE_DEC, NULL, 0, "Mobile Network Code", HFILL }},
            { &hf_gtp_rai_rac, { "RAC", "gtp.rac", FT_UINT8, BASE_DEC, NULL, 0, "Routing Area Code", HFILL }},
            { &hf_gtp_rai_lac, { "LAC", "gtp.lac", FT_UINT16, BASE_DEC, NULL, 0, "Location Area Code", HFILL }},
            { &hf_gtp_ranap_cause, { "RANAP cause", "gtp.ranap_cause", FT_UINT8, BASE_DEC, VALS(ranap_cause_type), 0, "RANAP cause", HFILL }},
            { &hf_gtp_recovery, { "Recovery", "gtp.recovery", FT_UINT8, BASE_DEC, NULL, 0, "Restart counter", HFILL }},
            { &hf_gtp_reorder, { "Reordering required","gtp.reorder", FT_BOOLEAN, BASE_NONE,NULL, 0, "Reordering required", HFILL }},
            { &hf_gtp_rnc_ipv4, { "RNC address IPv4", "gtp.rnc_ipv4", FT_IPv4, BASE_DEC, NULL, 0, "Radio Network Controller address IPv4", HFILL }},
            { &hf_gtp_rnc_ipv6, { "RNC address IPv6", "gtp.rnc_ipv6", FT_IPv6, BASE_HEX, NULL, 0, "Radio Network Controller address IPv6", HFILL }},
            { &hf_gtp_rp, { "Radio Priority", "gtp.rp", FT_UINT8, BASE_DEC, NULL, GTPv1_EXT_RP_MASK, "Radio Priority for uplink tx", HFILL }},
            { &hf_gtp_rp_nsapi, { "NSAPI in Radio Priority", "gtp.rp_nsapi", FT_UINT8, BASE_DEC, NULL, GTPv1_EXT_RP_NSAPI_MASK, "Network layer Service Access Point Identifier in Radio Priority", HFILL }},
            { &hf_gtp_rp_sms, { "Radio Priority SMS", "gtp.rp_sms",     FT_UINT8, BASE_DEC, NULL, 0, "Radio Priority for MO SMS", HFILL }},
            { &hf_gtp_rp_spare, { "Reserved", "gtp.rp_spare", FT_UINT8, BASE_DEC, NULL, GTPv1_EXT_RP_SPARE_MASK, "Spare bit", HFILL }},
            { &hf_gtp_sel_mode, { "Selection mode", "gtp.sel_mode", FT_UINT8, BASE_DEC, VALS(sel_mode_type), 0, "Selection Mode", HFILL }},
            { &hf_gtp_seq_number, { "Sequence number", "gtp.seq_number", FT_UINT16, BASE_HEX, NULL, 0, "Sequence Number", HFILL }},
            { &hf_gtp_sndcp_number, { "SNDCP N-PDU LLC Number", "gtp.sndcp_number", FT_UINT8, BASE_HEX, NULL, 0, "SNDCP N-PDU LLC Number", HFILL }},
            { &hf_gtp_tear_ind, { "Teardown Indicator", "gtp.tear_ind", FT_BOOLEAN, BASE_NONE,NULL, 0, "Teardown Indicator", HFILL }},
            { &hf_gtp_teid, { "TEID", "gtp.teid", FT_UINT32, BASE_HEX, NULL, 0, "Tunnel Endpoint Identifier", HFILL }},
            { &hf_gtp_teid_cp, { "TEID Control Plane", "gtp.teid_cp", FT_UINT32, BASE_HEX, NULL, 0, "Tunnel Endpoint Identifier Control Plane", HFILL }},
            { &hf_gtp_teid_data, { "TEID Data I", "gtp.teid_data", FT_UINT32, BASE_HEX, NULL, 0, "Tunnel Endpoint Identifier Data I", HFILL }},
            { &hf_gtp_teid_ii, { "TEID Data II", "gtp.teid_ii", FT_UINT32, BASE_HEX, NULL, 0, "Tunnel Endpoint Identifier Data II", HFILL }},
            { &hf_gtp_tft_code, { "TFT operation code", "gtp.tft_code", FT_UINT8, BASE_DEC, VALS (tft_code_type), GTPv1_TFT_CODE_MASK, "TFT operation code", HFILL }},
            { &hf_gtp_tft_spare, { "TFT spare bit",   "gtp.tft_spare", FT_UINT8, BASE_DEC, NULL, GTPv1_TFT_SPARE_MASK, "TFT spare bit", HFILL }},
            { &hf_gtp_tft_number, { "Number of packet filters", "gtp.tft_number", FT_UINT8, BASE_DEC, NULL, GTPv1_TFT_NUMBER_MASK, "Number of packet filters", HFILL }},
            { &hf_gtp_tft_eval, { "Evaluation precedence", "gtp.tft_eval", FT_UINT8, BASE_DEC, NULL, 0, "Evaluation precedence", HFILL }},
            { &hf_gtp_tid, { "TID", "gtp.tid", FT_STRING, BASE_DEC, NULL, 0, "Tunnel Identifier", HFILL }},
            { &hf_gtp_tlli, { "TLLI", "gtp.tlli", FT_UINT32, BASE_HEX, NULL, 0, "Temporary Logical Link Identity", HFILL }},
            { &hf_gtp_tr_comm, { "Packet transfer command", "gtp.tr_comm", FT_UINT8, BASE_DEC, VALS (tr_comm_type), 0, "Packat transfer command", HFILL }},
            { &hf_gtp_trace_ref, { "Trace reference", "gtp.trace_ref", FT_UINT16, BASE_HEX, NULL, 0, "Trace reference", HFILL }},
            { &hf_gtp_trace_type, { "Trace type", "gtp.trace_type", FT_UINT16, BASE_HEX, NULL, 0, "Trace type", HFILL }},
            { &hf_gtp_unknown, { "Unknown data (length)",   "gtp.unknown", FT_UINT16, BASE_DEC, NULL, 0, "Unknown data", HFILL }},
            { &hf_gtp_user_addr_pdp_org, { "PDP type organization", "gtp.user_addr_pdp_org", FT_UINT8, BASE_DEC, VALS(pdp_org_type), 0, "PDP type organization", HFILL }},
            { &hf_gtp_user_addr_pdp_type, { "PDP type number", "gtp.user_addr_pdp_type", FT_UINT8, BASE_HEX, VALS (pdp_type), 0, "PDP type", HFILL }},
            { &hf_gtp_user_ipv4, { "End user address IPv4", "gtp.user_ipv4", FT_IPv4, BASE_DEC, NULL, 0, "End user address IPv4", HFILL }},
            { &hf_gtp_user_ipv6, { "End user address IPv6", "gtp.user_ipv6", FT_IPv6, BASE_HEX, NULL, 0, "End user address IPv6", HFILL }},
            { &hf_gtp_security_mode,
                  { "Security Mode", "gtp.security_mode",
                  FT_UINT8, BASE_DEC, VALS(mm_sec_modep), 0xc0,
                  "Security Mode", HFILL }
            },
            { &hf_gtp_no_of_vectors,
                  { "No of Vectors", "gtp.no_of_vectors",
                  FT_UINT8, BASE_DEC, NULL, 0x38,
                  "No of Vectors", HFILL }
            },
            { &hf_gtp_cipher_algorithm,
                  { "Cipher Algorithm", "gtp.no_of_vectors",
                  FT_UINT8, BASE_DEC, VALS(gtp_cipher_algorithm), 0x07,
                  "Cipher Algorithm", HFILL }
            },
            { &hf_gtp_cksn_ksi,
                  { "Ciphering Key Sequence Number (CKSN)/Key Set Identifier (KSI)", "gtp.cksn_ksi",
                  FT_UINT8, BASE_DEC, NULL, 0x07,
                  "CKSN/KSI", HFILL }
            },
            { &hf_gtp_cksn,
                  { "Ciphering Key Sequence Number (CKSN)", "gtp.cksn_ksi",
                  FT_UINT8, BASE_DEC, NULL, 0x07,
                  "CKSN", HFILL }
            },
            { &hf_gtp_ksi,
                  { "Key Set Identifier (KSI)", "gtp.cksn_ksi",
                  FT_UINT8, BASE_DEC, NULL, 0x07,
                  "KSI", HFILL }
            },
            { &hf_gtp_ext_length,
                  { "Length", "gtp.ext_length",
                  FT_UINT16, BASE_DEC, NULL, 0x0,
                  "IE Length", HFILL }
            },
            { &hf_gtp_ext_apn_res,
                  { "Restriction Type", "gtp.ext_apn_res",
                  FT_UINT8, BASE_DEC, NULL, 0x0,
                  "Restriction Type", HFILL }
            },
            { &hf_gtp_ext_rat_type,
                  { "RAT Type", "gtp.ext_rat_type",
                  FT_UINT8, BASE_DEC, VALS(gtp_ext_rat_type_vals), 0x0,
                  "RAT Type", HFILL }
            },
            { &hf_gtp_ext_geo_loc_type,
                  { "Geographic Location Type", "gtp.ext_geo_loc_type",
                  FT_UINT8, BASE_DEC, NULL, 0x0,
                  "Geographic Location Type", HFILL }
            },
            { &hf_gtp_ext_sac,
                  { "SAC", "gtp.ext_sac",
                  FT_UINT16, BASE_HEX, NULL, 0x0,
                  "SAC", HFILL }
            },
            { &hf_gtp_ext_imeisv,
                  { "IMEI(SV)", "gtp.ext_imeisv",
                  FT_BYTES, BASE_NONE, NULL, 0x0,
                  "IMEI(SV)", HFILL }
            },
            { &hf_gtp_targetid,
                  { "TargetID", "gtp.targetid",
                  FT_UINT32, BASE_DEC, VALS(ranap_TargetID_vals), 0,
                  "TargetID", HFILL }},
            { &hf_gtp_bssgp_cause,
                  { "BSSGP Cause", "gtp.bssgp_cause",
                  FT_UINT8, BASE_DEC, VALS(tab_cause), 0,
                  "BSSGP Cause", HFILL }},

      };

      static gint *ett_gtp_array[] = {
            &ett_gtp,
            &ett_gtp_flags,
            &ett_gtp_ext,
            &ett_gtp_rai,
            &ett_gtp_qos,
            &ett_gtp_auth_tri,
            &ett_gtp_flow_ii,
            &ett_gtp_rab_cntxt,
            &ett_gtp_rp,
            &ett_gtp_pkt_flow_id,
            &ett_gtp_chrg_char,
            &ett_gtp_user,
            &ett_gtp_mm,
            &ett_gtp_trip,
            &ett_gtp_quint,
            &ett_gtp_pdp,
            &ett_gtp_apn,
            &ett_gtp_proto,
            &ett_gtp_gsn_addr,
            &ett_gtp_tft,
            &ett_gtp_tft_pf,
            &ett_gtp_tft_flags,
            &ett_gtp_rab_setup,
            &ett_gtp_hdr_list,
            &ett_gtp_chrg_addr,
            &ett_gtp_node_addr,
            &ett_gtp_rel_pack,
            &ett_gtp_can_pack,
            &ett_gtp_data_resp,
            &ett_gtp_priv_ext,
            &ett_gtp_net_cap,
            &ett_gtp_ext_tree_apn_res,
            &ett_gtp_ext_rat_type,
            &ett_gtp_ext_imeisv,
            &ett_gtp_ext_ran_tr_cont,
            &ett_gtp_ext_pdp_cont_prio,
            &ett_gtp_ext_ssgn_no,
            &ett_gtp_ext_rab_setup_inf,
            &ett_gtp_ext_common_flgs,
            &ett_gtp_ext_usr_loc_inf,
            &ett_gtp_ext_ms_time_zone,
            &ett_gtp_ext_camel_chg_inf_con,
            &ett_GTP_EXT_MBMS_UE_CTX,
            &ett_gtp_ext_tmgi,
            &ett_gtp_ext_rim_ra,
            &ett_gtp_ext_mbms_prot_conf_opt,
            &ett_gtp_ext_mbms_sa,
            &ett_gtp_ext_bms_ses_dur,
            &ett_gtp_ext_src_rnc_pdp_ctx_inf,
            &ett_gtp_ext_add_trs_inf,
            &ett_gtp_ext_hop_count,
            &ett_gtp_ext_sel_plmn_id,
            &ett_gtp_ext_mbms_ses_id,
            &ett_gtp_ext_mbms_2g_3g_ind,
            &ett_gtp_ext_enh_nsapi,
            &ett_gtp_ext_ad_mbms_trs_inf,
            &ett_gtp_ext_mbms_ses_id_rep_no,
            &ett_gtp_ext_mbms_time_to_data_tr,
            &ett_gtp_ext_ps_ho_req_ctx,
            &ett_gtp_ext_bss_cont,
            &ett_gtp_ext_cell_id,
            &ett_gtp_ext_pdu_no,
            &ett_gtp_ext_bssgp_cause,
            &ett_gtp_ext_ra_prio_lcs,
            &ett_gtp_target_id,
            &ett_gtp_utran_cont,
      };

      module_t    *gtp_module;

      proto_gtp = proto_register_protocol ("GPRS Tunneling Protocol", "GTP", "gtp");
      proto_register_field_array (proto_gtp, hf_gtp, array_length (hf_gtp));
      proto_register_subtree_array (ett_gtp_array, array_length (ett_gtp_array));

      gtp_module = prefs_register_protocol(proto_gtp, proto_reg_handoff_gtp);

      prefs_register_uint_preference(gtp_module, "v0_port", "GTPv0 port", "GTPv0 port (default 3386)", 10, &g_gtpv0_port);
      prefs_register_uint_preference(gtp_module, "v1c_port", "GTPv1 control plane (GTP-C) port", "GTPv1 control plane port (default 2123)", 10, &g_gtpv1c_port);
      prefs_register_uint_preference(gtp_module, "v1u_port", "GTPv1 user plane (GTP-U) port", "GTPv1 user plane port (default 2152)", 10, &g_gtpv1u_port);
      prefs_register_bool_preference(gtp_module, "dissect_tpdu", "Dissect T-PDU", "Dissect T-PDU", &gtp_tpdu);

      prefs_register_obsolete_preference (gtp_module, "v0_dissect_cdr_as");
      prefs_register_obsolete_preference (gtp_module, "v0_check_etsi");
      prefs_register_obsolete_preference (gtp_module, "v1_check_etsi");
      prefs_register_bool_preference (gtp_module, "check_etsi", "Compare GTP order with ETSI", "GTP ETSI order", &gtp_etsi_order);
      prefs_register_obsolete_preference(gtp_module, "ppp_reorder");

      /* This preference can be used to disable the dissection of GTP over TCP. Most of the Wireless operators uses GTP over UDP.
             * The preference is set to TRUE by default forbackward compatibility
             */
      prefs_register_bool_preference(gtp_module, "dissect_gtp_over_tcp", "Dissect GTP over TCP", "Dissect GTP over TCP", &gtp_over_tcp);

      register_dissector("gtp", dissect_gtp, proto_gtp);
}

void
proto_reg_handoff_gtp(void)
{
      static int Initialized = FALSE;
      static dissector_handle_t gtp_handle;


      if (!Initialized) {
            gtp_handle = find_dissector("gtp");
            ppp_subdissector_table = find_dissector_table("ppp.protocol");

            radius_register_avp_dissector(VENDOR_THE3GPP,5,dissect_radius_qos_umts);

            Initialized = TRUE;
      } else {
            dissector_delete ("udp.port", gtpv0_port, gtp_handle);
            dissector_delete ("udp.port", gtpv1c_port, gtp_handle);
            dissector_delete ("udp.port", gtpv1u_port, gtp_handle);

            if ( !gtp_over_tcp ) {
                  dissector_delete ("tcp.port", gtpv0_port, gtp_handle);
                  dissector_delete ("tcp.port", gtpv1c_port, gtp_handle);
                  dissector_delete ("tcp.port", gtpv1u_port, gtp_handle);
            }

      }

      gtpv0_port = g_gtpv0_port;
      gtpv1c_port = g_gtpv1c_port;
      gtpv1u_port = g_gtpv1u_port;

      dissector_add ("udp.port", g_gtpv0_port, gtp_handle);
      dissector_add ("udp.port", g_gtpv1c_port, gtp_handle);
      dissector_add ("udp.port", g_gtpv1u_port, gtp_handle);


      if ( gtp_over_tcp ) {
            dissector_add ("tcp.port", g_gtpv0_port, gtp_handle);
            dissector_add ("tcp.port", g_gtpv1c_port, gtp_handle);
            dissector_add ("tcp.port", g_gtpv1u_port, gtp_handle);
      }

      ip_handle = find_dissector("ip");
      ipv6_handle = find_dissector("ipv6");
      ppp_handle = find_dissector("ppp");
      data_handle = find_dissector("data");
      gtpcdr_handle = find_dissector("gtpcdr");
      bssap_pdu_type_table = find_dissector_table("bssap.pdu_type");

}

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