Adding upstream version 4.2.2.upstream/4.2.2

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

1 files changed, 1733 insertions, 0 deletions

diff --git a/epan/dissectors/packet-sgsap.c b/epan/dissectors/packet-sgsap.c
new file mode 100644
index 0000000..71f52ea
--- /dev/null
+++ b/epan/dissectors/packet-sgsap.c
@@ -0,0 +1,1733 @@
+/* packet-sgsap.c
+ * Routines for SGs Application Part (SGsAP) protocol dissection
+ *
+ * Copyright 2010 - 2017, Anders Broman <anders.broman@ericsson.com>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * References: 3GPP TS 29.118 V10.2.0 (2010-12)
+ */
+
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/prefs.h>
+#include <epan/expert.h>
+#include <epan/exceptions.h>
+#include <epan/show_exception.h>
+
+#include "packet-gsm_a_common.h"
+#include "packet-e212.h"
+
+#define PNAME  "SGs Application Part (SGsAP)"
+#define PSNAME "SGSAP"
+#define PFNAME "sgsap"
+
+
+void proto_register_sgsap(void);
+void proto_reg_handoff_sgsap(void);
+
+/* Global variables */
+static dissector_handle_t gsm_a_dtap_handle;
+
+/* The registered SCTP port number for SGsAP is 29118.
+ * The payload protocol identifier to be used for SGsAP is 0.
+ */
+#define SGSAP_SCTP_PORT_RANGE "29118"
+
+/* Initialize the protocol and registered fields */
+static int proto_sgsap = -1;
+
+static int hf_sgsap_msg_type = -1;
+int hf_sgsap_elem_id = -1;
+static int hf_sgsap_eps_location_update_type = -1;
+static int hf_sgsap_service_indicator_value = -1;
+static int hf_sgsap_sgs_cause = -1;
+static int hf_sgsap_ue_emm_mode = -1;
+static int hf_sgsap_eci = -1;
+static int hf_sgsap_cn_id = -1;
+static int hf_sgsap_imsi_det_eps = -1;
+static int hf_sgsap_imsi_det_non_eps = -1;
+static int hf_sgsap_lcs_indic = -1;
+static int hf_sgsap_mme_name = -1;
+static int hf_sgsap_vlr_name = -1;
+static int hf_sgsap_imeisv = -1;
+static int hf_sgsap_unknown_msg = -1;
+static int hf_sgsap_message_elements = -1;
+static int hf_sgsap_csri = -1;
+static int hf_sgsap_sel_cs_dmn_op = -1;
+
+static int ett_sgsap = -1;
+static int ett_sgsap_sel_cs_dmn_op = -1;
+
+static expert_field ei_sgsap_extraneous_data = EI_INIT;
+static expert_field ei_sgsap_missing_mandatory_element = EI_INIT;
+
+static dissector_handle_t sgsap_handle;
+
+static void get_sgsap_msg_params(guint8 oct, const gchar **msg_str, int *ett_tree, int *hf_idx, msg_fcn *msg_fcn_p);
+
+/*
+ * 9.4  Information elements
+ */
+/*
+ * 9.4.1    CLI
+ */
+
+/*
+ * Octets 3 to 14 contain the value part of the Calling party BCD number information element
+ * defined in subclause 10.5.4.9 of 3GPP TS 24.008 [8] (octets 3 to 14, i.e. not including
+ * 3GPP TS 24.008 IEI and 3GPP TS 24.008 length indicator)
+ * ( packet-gsm_a_dtap.c )
+ */
+/*
+ * 9.4.2    EPS location update type
+ */
+
+/* EPS location update type value (octet 3) */
+static const value_string sgsap_eps_location_update_type_values[] = {
+    { 0x00, "Shall not be sent in this version of the protocol" },
+    { 0x01, "IMSI attach" },
+    { 0x02, "Normal location update" },
+    { 0, NULL }
+};
+
+static guint16
+de_sgsap_eps_loc_upd_type(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+    guint8 oct;
+
+    curr_offset = offset;
+
+    /* Octet 3  EPS location update type value */
+    proto_tree_add_item(tree, hf_sgsap_eps_location_update_type, tvb, offset, 1, ENC_BIG_ENDIAN);
+    if (add_string) {
+        oct = tvb_get_guint8(tvb, curr_offset);
+        snprintf(add_string, string_len, " - %s", val_to_str_const(oct, sgsap_eps_location_update_type_values, "Reserved"));
+    }
+
+    curr_offset++;
+
+    return(curr_offset - offset);
+}
+/*
+ * 9.4.3    Erroneous message
+ *
+ * See subclause 18.4.5 in 3GPP TS 29.018 [16].
+ */
+static guint16
+de_sgsap_err_msg(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len, gchar *add_string , int string_len)
+{
+    const gchar     *msg_str;
+    gint             ett_tree;
+    int              hf_idx;
+    void(*msg_fcn_p)(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len);
+    guint8          oct;
+
+    /* 18.4.5 Erroneous message
+     * The Erroneous message IE is a TLV IE that encapsulates the message in error.
+     * Octet 3 - Octet n
+     * Erroneous message including the message type.
+     */
+     /* Messge type IE*/
+    oct = tvb_get_guint8(tvb, offset);
+    msg_fcn_p = NULL;
+    ett_tree = -1;
+    hf_idx = -1;
+    msg_str = NULL;
+
+    proto_tree_add_item(tree, hf_sgsap_msg_type, tvb, offset, 1, ENC_BIG_ENDIAN);
+
+    get_sgsap_msg_params(oct, &msg_str, &ett_tree, &hf_idx, &msg_fcn_p);
+    if (msg_str) {
+        if (add_string)
+            snprintf(add_string, string_len, " - %s", msg_str);
+
+    }
+    if (msg_fcn_p){
+        volatile guint32 curr_offset = offset + 1;
+        TRY {
+            /*let's try to decode erroneous message and catch exceptions as it could be malformed */
+            (*msg_fcn_p)(tvb, tree, pinfo, curr_offset, len - 1);
+        } CATCH_BOUNDS_ERRORS {
+            show_exception(tvb, pinfo, tree, EXCEPT_CODE, GET_MESSAGE);
+        } ENDTRY
+    }
+
+
+    return(len);
+}
+/*
+ * 9.4.3a   E-UTRAN Cell Global Identity
+ *
+ * The coding of the E-UTRAN Cell Global Identity value is according to ECGI field information element
+ * as specified in subclause 8.21.5 of 3GPP TS 29.274 [17A] (GTPv2-C)
+ */
+guint16
+de_sgsap_ecgi(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32    curr_offset;
+
+    curr_offset = offset;
+
+    dissect_e212_mcc_mnc(tvb, pinfo, tree, offset, E212_ECGI, TRUE);
+    curr_offset += 3;
+
+    proto_tree_add_item(tree, hf_sgsap_eci, tvb, curr_offset, 4, ENC_BIG_ENDIAN);
+    curr_offset += 4;
+
+    return(curr_offset-offset);
+}
+/*
+ * 9.4.4    Global CN-Id
+ *
+ * See subclause 18.4.27 in 3GPP TS 29.018 [16].
+ * 18.4.27 Global CN-Id
+ * The Global CN-Id consists of a PLMN-Id and a CN-Id, see 3GPP TS 23.003. The PLMN-Id consists of MCC and MNC
+ * coded according to Location Area Identification in 3GPP TS 24.008. The CN-Id is an integer defined by O&M. The
+ * least significant bit of the CN-Id field is bit 1 of octet 7 and the most significant bit is bit 8 of octet 6. If the CN-Id does
+ * not fill the field reserved for it, the rest of the bits are set to '0'.
+ */
+static guint16
+de_sgsap_g_cn_id(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32    curr_offset;
+
+    curr_offset = offset;
+
+    dissect_e212_mcc_mnc(tvb, pinfo, tree, offset, E212_NONE, TRUE);
+    curr_offset += 3;
+
+    proto_tree_add_item(tree, hf_sgsap_cn_id, tvb, curr_offset, 2, ENC_BIG_ENDIAN);
+    curr_offset += 2;
+
+    return(curr_offset-offset);
+}
+/*
+ * 9.4.5    IMEISV
+ * See subclause 18.4.9 in 3GPP TS 29.018 [16].
+ * The IMEISV is coded as a sequence of BCD digits, compressed two into each octet.
+ * The IMEISV consists of 16 digits
+ * (see 3GPP TS 23.003).
+ */
+static guint16
+de_sgsap_imeisv(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    char       *imeisv_str;
+    guint32     curr_offset;
+
+    curr_offset = offset;
+
+    proto_tree_add_item_ret_display_string(tree, hf_sgsap_imeisv, tvb, curr_offset, len, ENC_BCD_DIGITS_0_9, pinfo->pool, &imeisv_str);
+    if (add_string) {
+        /* (len<<2)+4 = the maximum number of bytes to produce (including the terminating nul character). */
+        snprintf(add_string, (len<<2)+4, " - %s", imeisv_str);
+    }
+
+    return(len);
+}
+
+/*
+ * 9.4.6    IMSI
+ * See subclause 18.4.10 in 3GPP TS 29.018 [16].
+ */
+/* The IMSI is coded as a sequence of BCD digits, compressed two into each octet.
+ * This is a variable length element, and includes a length indicator.
+ * The IMSI is defined in 3GPP TS 23.003. It shall not exceed 15 digits (see 3GPP TS 23.003).
+ */
+/*
+ * 9.4.7    IMSI detach from EPS service type
+ */
+
+/* IMSI detach from EPS service type value (octet 3) */
+static const value_string sgsap_imsi_det_from_eps_serv_type_values[] = {
+    { 0x00, "Interpreted as reserved in this version of the protocol" },
+    { 0x01, "Network initiated IMSI detach from EPS services" },
+    { 0x02, "UE initiated IMSI detach from EPS services" },
+    { 0x03, "EPS services not allowed" },
+    { 0, NULL }
+};
+
+static guint16
+de_sgsap_imsi_det_eps(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+
+    curr_offset = offset;
+
+    proto_tree_add_item(tree, hf_sgsap_imsi_det_eps, tvb, curr_offset, 1, ENC_BIG_ENDIAN);
+    curr_offset += 1;
+
+    return(curr_offset-offset);
+}
+/*
+ * 9.4.8    IMSI detach from non-EPS service type
+ */
+/* IMSI detach from non-EPS service type value (octet 3)*/
+static const value_string sgsap_imsi_det_from_non_eps_serv_type_values[] = {
+    { 0x00, "Interpreted as reserved in this version of the protocol" },
+    { 0x01, "Explicit UE initiated IMSI detach from non-EPS services" },
+    { 0x02, "Combined UE initiated IMSI detach from EPS and non-EPS services" },
+    { 0x03, "Implicit network initiated IMSI detach from non-EPS services" },
+    { 0, NULL }
+};
+
+static guint16
+de_sgsap_imsi_det_non_eps(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+
+    curr_offset = offset;
+
+    proto_tree_add_item(tree, hf_sgsap_imsi_det_non_eps, tvb, curr_offset, 1, ENC_BIG_ENDIAN);
+    curr_offset += 1;
+
+    return(curr_offset-offset);
+}
+/*
+ * 9.4.9    LCS client identity
+ * The coding of the LCS client identity value is according to LCS-ClientID
+ * as specified in subclause 17.7.13 of 3GPP TS 29.002 [15]
+ * (packet-nas_eps.c)
+ */
+/*
+ * 9.4.10   LCS indicator
+ */
+static const value_string sgsap_lcs_indic_values[] = {
+    { 0x00, "Normal, unspecified in this version of the protocol" },
+    { 0x01, "MT-LR" },
+    { 0, NULL }
+};
+
+static guint16
+de_sgsap_lcs_indic(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+
+    curr_offset = offset;
+
+    proto_tree_add_item(tree, hf_sgsap_lcs_indic, tvb, curr_offset, 1, ENC_BIG_ENDIAN);
+    curr_offset += 1;
+
+    return(curr_offset-offset);
+}
+/*
+ * 9.4.11   Location area identifier
+ *
+ * Octets 3 to 7 contain the value part of the Location area identification information element
+ * defined in 3GPP TS 24.008 [8] (starting with octet 2, i.e. not including 3GPP TS 24.008 IEI)
+ *(packet-gsm_a_common.c)
+ */
+/*
+ * 9.4.12   MM information
+ * For the coding see subclause 18.4.16 in 3GPP TS 29.018 [16].
+ * User information: This field is composed of one or more of the
+ * information elements of the MM information message as defined in
+ * 3GPP TS 24.008, excluding the Protocol discriminator, Skip
+ * indicator and Message type. This field includes the IEI and length
+ * indicatior of the other information elements.
+ */
+static guint16
+de_sgsap_mm_info(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+
+    curr_offset = offset;
+
+    dtap_mm_mm_info(tvb, tree, pinfo, curr_offset, len);
+
+    return(len);
+}
+
+/*
+ * 9.4.13   MME name
+ */
+static guint16
+de_sgsap_mme_name(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint   name_len;
+    guint8  *fqdn = NULL;
+
+    /* The MME name information element specifies the MME name and is coded as shown in figure 9.4.13.1. Octets 3
+     * through n contain the name in the form of a fully qualified domain name (FQDN) as specified in 3GPP TS 23.003 [3].
+     * The value part of the MME name information element (not including IEI and length indicator) shall have a length of 55
+     * octets.
+     */
+    if (len > 0) {
+        name_len = tvb_get_guint8(tvb, offset);
+
+        if (name_len < 0x20) {
+            fqdn = tvb_get_string_enc(pinfo->pool, tvb, offset, len, ENC_APN_STR);
+        } else{
+            fqdn = tvb_get_string_enc(pinfo->pool, tvb, offset, len, ENC_ASCII);
+        }
+        proto_tree_add_string(tree, hf_sgsap_mme_name, tvb, offset, len, fqdn);
+        if (add_string)
+            snprintf(add_string, string_len, " - %s", fqdn);
+
+    }
+
+    return(len);
+}
+/*
+ * 9.4.14   Mobile identity
+ * See subclause 18.4.17 in 3GPP TS 29.018 [16].
+ * (packet-gsm_a_common.c)
+ */
+/*
+ * 9.4.14a  Mobile Station Classmark 2
+ * With the exception of the IEI, the contents are specified in subclause 10.5.1.6 in 3GPP TS 24.008 [8].
+ * (packet-gsm_a_common.c)
+ */
+/*
+ * 9.4.15   NAS message container
+ * Octets 3 to 253 contain the SMS message (i.e. CP DATA, CP ACK or CP ERROR)
+ * as defined in subclause 7.2 of 3GPP TS 24.011 [10]
+ */
+static guint16
+de_sgsap_nas_msg_container(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len, gchar *add_string _U_, int string_len _U_)
+{
+    tvbuff_t *new_tvb;
+    guint32 curr_offset;
+
+    curr_offset = offset;
+
+    /* Octets 3 to 253 contain the SMS message (i.e. CP DATA, CP ACK or CP ERROR)
+     * as defined in subclause 7.2 of 3GPP TS 24.011 [10]
+     */
+    new_tvb = tvb_new_subset_length(tvb, curr_offset, len);
+    if (gsm_a_dtap_handle) {
+        call_dissector(gsm_a_dtap_handle, new_tvb, pinfo, tree);
+    }
+
+    return(len);
+}
+/*
+ * 9.4.16   Reject cause
+ * See subclause 18.4.21 in 3GPP TS 29.018 [16].
+ * The rest of the information element is coded as the value part of
+ * the reject cause IE defined in 3GPP TS 24.008, not including
+ * 3GPP TS 24.008 IEI.
+ * (packet-gsm_a_dtap.c)
+ */
+/*
+ * 9.4.17   Service indicator
+ */
+
+/* Octet 3  Service indicator value */
+static const value_string sgsap_service_indicator_values[] = {
+    { 0x00, "Shall not be sent in this version of the protocol" },
+    { 0x01, "CS call indicator" },
+    { 0x02, "SMS indicator" },
+    { 0, NULL }
+};
+
+static guint16
+de_sgsap_serv_indic(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+    guint8 oct;
+
+    curr_offset = offset;
+
+    /* Octet 3  Service indicator value */
+    proto_tree_add_item(tree, hf_sgsap_service_indicator_value, tvb, offset, 1, ENC_BIG_ENDIAN);
+    if (add_string) {
+        oct = tvb_get_guint8(tvb, curr_offset);
+        snprintf(add_string, string_len, " - %s", val_to_str_const(oct, sgsap_service_indicator_values, "Reserved"));
+    }
+    curr_offset++;
+
+    return(curr_offset - offset);
+}
+/*
+ * 9.4.18   SGs cause
+ */
+
+/* SGs cause value (octet 3) */
+static const value_string sgsap_sgs_cause_values[] = {
+    { 0x00, "Normal, unspecified in this version of the protocol" },
+    { 0x01, "IMSI detached for EPS services" },
+    { 0x02, "IMSI detached for EPS and non-EPS services" },
+    { 0x03, "IMSI unknown" },
+    { 0x04, "IMSI detached for non-EPS services" },
+    { 0x05, "IMSI implicitly detached for non-EPS services" },
+    { 0x06, "UE unreachable" },
+    { 0x07, "Message not compatible with the protocol state" },
+    { 0x08, "Missing mandatory information element" },
+    { 0x09, "Invalid mandatory information" },
+    { 0x0a, "Conditional information element error" },
+    { 0x0b, "Semantically incorrect message" },
+    { 0x0c, "Message unknown" },
+    { 0x0d, "Mobile terminating CS fallback call rejected by the user" },
+    { 0x0e, "UE temporarily unreachable" },
+    { 0, NULL }
+};
+
+static value_string_ext sgsap_sgs_cause_values_ext = VALUE_STRING_EXT_INIT(sgsap_sgs_cause_values);
+
+static guint16
+de_sgsap_sgs_cause(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+    guint8 oct;
+
+    curr_offset = offset;
+
+    proto_tree_add_item(tree, hf_sgsap_sgs_cause, tvb, offset, 1, ENC_BIG_ENDIAN);
+    if (add_string) {
+        oct = tvb_get_guint8(tvb, curr_offset);
+        snprintf(add_string, string_len, " - %s", val_to_str_ext_const(oct, &sgsap_sgs_cause_values_ext, "Reserved"));
+    }
+    curr_offset++;
+
+    return(curr_offset - offset);
+}
+/*
+ * 9.4.19   SS code
+ * The coding of the SS code value is according to SS-Code as specified in
+ * subclause 17.7.5 of 3GPP TS 29.002 [15]
+ * ( packet-nas_eps.c)
+ */
+/*
+ * 9.4.20   TMSI
+ * See subclause 18.4.23 in 3GPP TS 29.018 [16].
+ * (packet-gsm_a_bssmap.c)
+ */
+
+/*
+ * 9.4.21   TMSI status
+ *
+ * See subclause 18.4.24 in 3GPP TS 29.018 [16].
+ * (packet-gsm_a_gm.c)
+ */
+/*
+ * 9.4.21a  Tracking Area Identity
+ * Octets 3 to 7 contain the value part of the Tracking Area Identity information element defined in 3GPP TS 24.301 [14]
+ * (starting with octet 2, i.e. not including 3GPP TS 24.301 IEI)
+ * (packet-nas_eps.c)
+ */
+/*
+ * 9.4.21b  UE Time Zone
+ * The coding of the UE Time Zone value is according to value part of the Time Zone information element as specified
+ * in subclause 10.5.3.8 of 3GPP TS 24.008 [8] (i.e. not including 3GPP TS 24.008 IEI)
+ * (packet-gsm_a_dtap.c)
+ */
+/*
+ * 9.4.21c  UE EMM mode
+ */
+static const value_string sgsap_ue_emm_mode_values[] = {
+    { 0x00, "EMM-IDLE" },
+    { 0x01, "EMM-CONNECTED" },
+    { 0, NULL }
+};
+
+static guint16
+de_sgsap_ue_emm_mode(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint32 curr_offset;
+
+    curr_offset = offset;
+
+    proto_tree_add_item(tree, hf_sgsap_ue_emm_mode, tvb, offset, 1, ENC_BIG_ENDIAN);
+    curr_offset += 1;
+
+    return(curr_offset - offset);
+}
+/*
+ * 9.4.22   VLR name
+ */
+static guint16
+de_sgsap_vlr_name(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    guint     name_len;
+    guint8  *fqdn = NULL;
+
+    /* The VLR name information element specifies the VLR name and is coded as shown in figure 9.4.22.1.
+     * Octets 3 through n contain the VLR name in the form of a fully qualified domain name (FQDN)
+     * as specified in IETF RFC 1035 [21].
+     */
+    if (len > 0) {
+        name_len = tvb_get_guint8(tvb, offset);
+
+        if (name_len < 0x20) {
+            fqdn = tvb_get_string_enc(pinfo->pool, tvb, offset, len, ENC_APN_STR);
+        } else{
+            fqdn = tvb_get_string_enc(pinfo->pool, tvb, offset, len, ENC_ASCII);
+        }
+        proto_tree_add_string(tree, hf_sgsap_vlr_name, tvb, offset, len, fqdn);
+        if (add_string)
+            snprintf(add_string, string_len, " - %s", fqdn);
+    }
+
+    return(len);
+}
+
+/*
+ * 9.4.23   Channel needed
+ * See subclause 18.4.2 in 3GPP TS 29.018 [16].
+ * The rest of the information element is coded as the IEI part and the
+ * value part of the Channel Needed IE defined in 3GPP TS 44.018
+ * (packet-gsm_a_bssmap.c)
+ */
+/*
+ * 9.4.24   eMLPP priority
+ * See subclause 18.4.4 in 3GPP TS 29.018 [16].
+ * The rest of the information element is coded as the value part of
+ * the eMLPP-Priority IE defined in 3GPP TS 48.008 (not including
+ * 3GPP TS 48.008 IEI and 3GPP TS 48.008 length indicator).
+ * (packet-gsm_a_bssmap.c)
+ */
+
+/*
+ *
+ */
+static guint16
+de_sgsap_add_paging_ind(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+
+    /* Octet 3 0 0 0 0 0 0 0 CSRI */
+    proto_tree_add_item(tree, hf_sgsap_csri, tvb, offset, 1, ENC_BIG_ENDIAN);
+
+    return(len);
+}
+
+#if 0
+Reuse GSM_A_PDU_TYPE_GM, DE_NET_RES_ID_CONT
+/*
+ * 9.4.26 TMSI based NRI container
+ */
+static guint16
+de_sgsap_tmsi_based_nri_cont(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+
+    /* See subclause 18.4.28 in 3GPP TS 29.018 [16].
+     * Which says The TMSI based NRI container value value consists of 10 bits which correspond to bits 23 to 14 of the valid TMSI
+     * (3GPP TS 23.236 and
+     * Octet 3 and Octet 4 The rest of the information element is coded as the value part of the Network resource identifier container IE
+     * defined in 3GPP TS 24.008.
+     */
+    return(len);
+}
+#endif
+/*
+* 9.4.27 Selected CS domain operator
+*/
+static guint16
+de_sgsap_selected_cs_dmn_op(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len _U_, gchar *add_string _U_, int string_len _U_)
+{
+    proto_item *item;
+    proto_tree *sub_tree;
+    /* Coded as octets 2 to 4 of the Location Area Identification IE,
+     * defined in 3GPP TS 24.008 [8] (not including 3GPP TS 24.008 IEI
+     * and LAC).(10.5.1.3 Location Area Identification)
+     * MCC digit 2 MCC digit 1 octet 2
+     * MNC digit 3 MCC digit 3 octet 3
+     * MNC digit 2 MNC digit 1 octet 4
+     */
+    item = proto_tree_add_item(tree, hf_sgsap_sel_cs_dmn_op, tvb, offset, 1, ENC_NA);
+    sub_tree = proto_item_add_subtree(item, ett_sgsap_sel_cs_dmn_op);
+
+    dissect_e212_mcc_mnc_wmem_packet_str(tvb, pinfo, sub_tree, offset, E212_LAI, TRUE);
+
+    return(len);
+}
+
+static const value_string sgsap_elem_strings[] = {
+    { DE_SGSAP_IMSI, "IMSI" },                                              /* 9.4.6 */
+    { DE_SGSAP_VLR_NAME, "VLR name" },                                      /* 9.4.22 */
+    { DE_SGSAP_TMSI, "TMSI" },                                              /* 9.4.20 */
+    { DE_SGSAP_LOC_AREA_ID, "Location area identifier" },                   /* 9.4.11 */
+    { DE_SGSAP_CH_NEEDED, "Channel Needed" },                               /* 9.4.23 */
+    { DE_SGSAP_EMLPP_PRIO, "eMLPP Priority" },                              /* 9.4.24 */
+    { DE_SGSAP_TMSI_STATUS, "TMSI status" },                                /* 9.4.21 */
+    { DE_SGSAP_SGS_CAUSE, "SGs cause" },                                    /* 9.4.18 */
+    { DE_SGSAP_MME_NAME, "MME name" },                                      /* 9.4.13 */
+    { DE_SGSAP_EPS_LOC_UPD_TYPE, "EPS location update type" },              /* 9.4.2 */
+    { DE_SGSAP_GLOBAL_CN_ID, "Global CN-Id" },                              /* 9.4.4 */
+
+    { DE_SGSAP_UDEF_11, "Undefined" },                                      /*  */
+    { DE_SGSAP_UDEF_12, "Undefined" },                                      /*  */
+
+    { DE_SGSAP_MID, "Mobile identity" },                                    /* 9.4.14 */
+    { DE_SGSAP_REJ_CAUSE, "Reject cause" },                                 /* 9.4.16 */
+    { DE_SGSAP_IMSI_DET_EPS, "IMSI detach from EPS service type" },         /* 9.4.7 */
+    { DE_SGSAP_IMSI_DET_NON_EPS, "IMSI detach from non-EPS service type" }, /* 9.4.8 */
+
+    { DE_SGSAP_IMEISV, "IMEISV" },                                          /* 9.4.5 */
+    { DE_SGSAP_NAS_MSG_CONTAINER, "NAS message container" },                /* 9.4.15 */
+    { DE_SGSAP_MM_INFO, "MM information" },                                 /* 9.4.12 */
+
+    { DE_SGSAP_UDEF_20, "Undefined" },                                      /*  */
+    { DE_SGSAP_UDEF_21, "Undefined" },                                      /*  */
+    { DE_SGSAP_UDEF_22, "Undefined" },                                      /*  */
+
+    { DE_SGSAP_ERR_MSG, "Erroneous message" },                              /* 9.4.3 */
+    { DE_SGSAP_CLI, "CLI" },                                                /* 9.4.1 */
+    { DE_SGSAP_LCS_CLIENT_ID, "LCS client identity" },                      /* 9.4.9 */
+    { DE_SGSAP_LCS_INDIC, "LCS indicator" },                                /* 9.4.10 */
+    { DE_SGSAP_SS_CODE, "SS code" },                                        /* 9.4.19 */
+    { DE_SGSAP_SERV_INDIC, "Service indicator" },                           /* 9.4.17 */
+    { DE_SGSAP_UE_TZ, "UE Time Zone" },                                     /* 9.4.21b */
+    { DE_SGSAP_MSC_2, "Mobile Station Classmark 2" },                       /* 9.4.14a */
+    { DE_SGSAP_TAID, "Tracking Area Identity" },                            /* 9.4.21a */
+    { DE_SGSAP_ECGI, "E-UTRAN Cell Global Identity" },                      /* 9.4.3a */
+    { DE_SGSAP_UE_EMM_MODE, "UE EMM mode" },                                /* 9.4.21c */
+    { DE_SGSAP_ADD_PAGING_IND, "Additional paging indicators" },            /* 9.4.25 */
+    { DE_SGSAP_TMSI_BASED_NRI_CONT, "TMSI based NRI container" },           /* 9.4.26 */
+    { DE_SGSAP_SELECTED_CS_DMN_OP, "Selected CS domain operator" },         /* 9.4.27 */
+    { 0, NULL }
+};
+value_string_ext sgsap_elem_strings_ext = VALUE_STRING_EXT_INIT(sgsap_elem_strings);
+
+#define NUM_SGSAP_ELEM (sizeof(sgsap_elem_strings)/sizeof(value_string))
+gint ett_sgsap_elem[NUM_SGSAP_ELEM];
+#if 0
+This enum has been moved to packet-gsm_a_common to
+make it possible to use element dissecton from this dissector
+in other dissectors.
+It is left here as a comment for easier reference.
+
+Note this enum must be of the same size as the element decoding list
+
+typedef enum
+{
+
+    DE_SGSAP_IMSI,                                  /. 9.4.6 IMSI./
+    DE_SGSAP_VLR_NAME,                              /. 9.4.22 VLR name./
+    DE_SGSAP_TMSI,                                  /. 9.4.20 TMSI ./
+    DE_SGSAP_LOC_AREA_ID,                           /. 9.4.11 Location area identifier ./
+    DE_SGSAP_CH_NEEDED,                             /. 9.4.23 Channel Needed ./
+    DE_SGSAP_EMLPP_PRIO,                            /. 9.4.24 eMLPP Priority./
+    DE_SGSAP_TMSI_STATUS,                           /. 9.4.21 TMSI status ./
+    DE_SGSAP_SGS_CAUSE,                             /. 9.4.18 SGs cause./
+    DE_SGSAP_MME_NAME,                              /. 9.4.13 MME name./
+    DE_SGSAP_EPS_LOC_UPD_TYPE,                      /. 9.4.2 EPS location update type./
+    DE_SGSAP_GLOBAL_CN_ID,                          /. 9.4.4 Global CN-Id./
+
+    DE_SGSAP_UDEF_11,                               /. Undefined ./
+    DE_SGSAP_UDEF_12,                               /. Undefined ./
+
+    DE_SGSAP_MID,                                   /. 9.4.14 Mobile identity./
+    DE_SGSAP_REJ_CAUSE,                             /. 9.4.16 Reject cause ./
+    DE_SGSAP_IMSI_DET_EPS,                          /. 9.4.7 IMSI detach from EPS service type ./
+    DE_SGSAP_IMSI_DET_NON_EPS,                      /. 9.4.8 IMSI detach from non-EPS service type ./
+
+    DE_SGSAP_IMEISV,                                /. 9.4.5 IMEISV ./
+    DE_SGSAP_NAS_MSG_CONTAINER,                     /. 9.4.15 NAS message container./
+    DE_SGSAP_MM_INFO,                               /. 9.4.12 MM information./
+
+    DE_SGSAP_UDEF_20,                               /. Undefined ./
+    DE_SGSAP_UDEF_21,                               /. Undefined ./
+    DE_SGSAP_UDEF_22,                               /. Undefined ./
+
+    DE_SGSAP_ERR_MSG,                               /. 9.4.3 Erroneous message./
+    DE_SGSAP_CLI,                                   /. 9.4.1 CLI ./
+    DE_SGSAP_LCS_CLIENT_ID,                         /. 9.4.9 LCS client identity ./
+    DE_SGSAP_LCS_INDIC,                             /. 9.4.10 LCS indicator ./
+    DE_SGSAP_SS_CODE,                               /. 9.4.19 SS code ./
+    DE_SGSAP_SERV_INDIC,                            /. 9.4.17 Service indicator ./
+    DE_SGSAP_UE_TZ,                                 /. 9.4.21b UE Time Zone ./
+    DE_SGSAP_MSC_2,                                 /. 9.4.14a Mobile Station Classmark 2 ./
+    DE_SGSAP_TAID,                                  /. 9.4.21a Tracking Area Identity ./
+    DE_SGSAP_ECGI,                                  /. 9.4.3a E-UTRAN Cell Global Identity ./
+    DE_SGSAP_UE_EMM_MODE,                           /. 9.4.21c UE EMM mode./
+    DE_SGSAP_ADD_PAGING_IND,                        /. 9.4.25 Additional paging indicators ./
+    DE_SGSAP_TMSI_BASED_NRI_CONT,                   /. 9.4.26 TMSI based NRI container ./
+    DE_SGSAP_SELECTED_CS_DMN_OP,                    /. 9.4.27 Selected CS domain operator ./
+
+    DE_SGAP_NONE                            /. NONE ./
+}
+sgsap_elem_idx_t;
+#endif /* 0 */
+
+guint16 (*sgsap_elem_fcn[])(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len, gchar *add_string, int string_len) = {
+    NULL/*DE_SGSAP_IMSI*/,                                  /* 9.4.6 IMSI*/
+    de_sgsap_vlr_name,                                      /* 9.4.22 VLR name*/
+    NULL/*DE_SGSAP_TMSI*/,                                  /* 9.4.20 TMSI */
+    NULL/*DE_SGSAP_LOC_AREA_ID*/,                           /* 9.4.11 Location area identifier */
+    NULL/*DE_SGSAP_CH_NEEDED*/,                             /* 9.4.23 Channel Needed */
+    NULL/*DE_SGSAP_EMLPP_PRIO*/,                            /* 9.4.24 eMLPP Priority*/
+    NULL/*DE_SGSAP_TMSI_STATUS*/,                           /* 9.4.21 TMSI status */
+    de_sgsap_sgs_cause,                                     /* 9.4.18 SGs cause*/
+    de_sgsap_mme_name,                                      /* 9.4.13 MME name*/
+    de_sgsap_eps_loc_upd_type,                              /* 9.4.2 EPS location update type*/
+    de_sgsap_g_cn_id,                                       /* 9.4.4 Global CN-Id*/
+
+    NULL/*DE_SGSAP_UDEF_11*/,                               /* Undefined */
+    NULL/*DE_SGSAP_UDEF_12*/,                               /* Undefined */
+
+    NULL/*DE_SGSAP_MID*/,                                   /* 9.4.14 Mobile identity*/
+    NULL/*DE_SGSAP_REJ_CAUSE*/,                             /* 9.4.16 Reject cause */
+    de_sgsap_imsi_det_eps,                                  /* 9.4.7 IMSI detach from EPS service type */
+    de_sgsap_imsi_det_non_eps,                              /* 9.4.8 IMSI detach from non-EPS service type */
+
+    de_sgsap_imeisv,                                        /* 9.4.5 IMEISV */
+    de_sgsap_nas_msg_container,                             /* 9.4.15 NAS message container*/
+    de_sgsap_mm_info,                                       /* 9.4.12 MM information*/
+
+    NULL/*DE_SGSAP_UDEF_20*/,                               /* Undefined */
+    NULL/*DE_SGSAP_UDEF_21*/,                               /* Undefined */
+    NULL/*DE_SGSAP_UDEF_22*/,                               /* Undefined */
+
+    de_sgsap_err_msg,                                       /* 9.4.3 Erroneous message*/
+    NULL/*DE_SGSAP_CLI*/,                                   /* 9.4.1 CLI */
+    NULL/*DE_SGSAP_LCS_CLIENT_ID*/,                         /* 9.4.9 LCS client identity */
+    de_sgsap_lcs_indic,                                     /* 9.4.10 LCS indicator */
+    NULL/*DE_SGSAP_SS_CODE*/,                               /* 9.4.19 SS code */
+    de_sgsap_serv_indic,                                    /* 9.4.17 Service indicator */
+    NULL/*DE_SGSAP_UE_TZ*/,                                 /* 9.4.21b UE Time Zone */
+    NULL/*DE_SGSAP_MSC_2*/,                                 /* 9.4.14a Mobile Station Classmark 2 */
+    NULL/*DE_SGSAP_TAID*/,                                  /* 9.4.21a Tracking Area Identity */
+    de_sgsap_ecgi,                                          /* 9.4.3a E-UTRAN Cell Global Identity */
+    de_sgsap_ue_emm_mode,                                   /* 9.4.21c UE EMM mode*/
+    de_sgsap_add_paging_ind,                                /* 9.4.25 Additional paging indicators */
+    NULL/*DE_SGSAP_TMSI_BASED_NRI_CONT */,                  /* 9.4.26 TMSI based NRI container (Reuse GSM_A_PDU_TYPE_GM, DE_NET_RES_ID_CONT */
+    de_sgsap_selected_cs_dmn_op,                            /* 9.4.27 Selected CS domain operator */
+    NULL,   /* NONE */
+};
+
+/* MESSAGE FUNCTIONS */
+
+/*
+ * 8.1  SGsAP-ALERT-ACK message
+ */
+static void
+sgsap_alert_ack(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.2  SGsAP-ALERT-REJECT message
+ */
+static void
+sgsap_alert_rej(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* SGs Cause    SGs cause  9.4.18   M   TLV 3 */
+    ELEM_MAND_TLV(0x08, SGSAP_PDU_TYPE, DE_SGSAP_SGS_CAUSE, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.3  SGsAP-ALERT-REQUEST message
+ */
+static void
+sgsap_alert_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.4  SGsAP-DOWNLINK-UNITDATA message
+ */
+static void
+sgsap_dl_unitdata(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* NAS message container    NAS message container 9.4.15    M   TLV 4-253 */
+    ELEM_MAND_TLV(0x16, SGSAP_PDU_TYPE, DE_SGSAP_NAS_MSG_CONTAINER, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.5  SGsAP-EPS-DETACH-ACK message
+ */
+
+static void
+sgsap_eps_det_ack(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.6  SGsAP-EPS-DETACH-INDICATION message
+ */
+
+static void
+sgsap_eps_det_ind(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* MME name MME name 9.4.13 M   TLV 57 */
+    ELEM_MAND_TLV(0x09, SGSAP_PDU_TYPE, DE_SGSAP_MME_NAME, NULL, ei_sgsap_missing_mandatory_element);
+    /* IMSI detach from EPS service type    IMSI detach from EPS service type 9.4.7 M   TLV 3 */
+    ELEM_MAND_TLV(0x10, SGSAP_PDU_TYPE, DE_SGSAP_IMSI_DET_EPS, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.7  SGsAP-IMSI-DETACH-ACK message
+ */
+static void
+sgsap_imsi_det_ack(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.8  SGsAP-IMSI-DETACH-INDICATION message
+ */
+static void
+sgsap_imsi_det_ind(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* MME name MME name 9.4.13 M   TLV 57 */
+    ELEM_MAND_TLV(0x09, SGSAP_PDU_TYPE, DE_SGSAP_MME_NAME, NULL, ei_sgsap_missing_mandatory_element);
+    /* IMSI Detach from non-EPS service type    IMSI detach from non-EPS service type 9.4.8 M   TLV 3 */
+    ELEM_MAND_TLV(0x11, SGSAP_PDU_TYPE, DE_SGSAP_IMSI_DET_NON_EPS, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.9  SGsAP-LOCATION-UPDATE-ACCEPT message
+ */
+static void
+sgsap_imsi_loc_update_acc(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* Location area identifier Location area identifier 9.4.11 M   TLV 7 */
+    ELEM_MAND_TLV(0x04, GSM_A_PDU_TYPE_COMMON, DE_LAI, NULL, ei_sgsap_missing_mandatory_element);
+    /* New TMSI, or IMSI    Mobile identity 9.4.14  O   TLV 6-10 */
+    ELEM_OPT_TLV(0x0e, GSM_A_PDU_TYPE_COMMON, DE_MID, " - New TMSI, or IMSI");
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.10 SGsAP-LOCATION-UPDATE-REJECT message
+ */
+static void
+sgsap_imsi_loc_update_rej(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* Reject cause Reject cause 9.4.16 M   TLV 3 */
+    ELEM_MAND_TLV(0x0f, GSM_A_PDU_TYPE_DTAP, DE_REJ_CAUSE, NULL, ei_sgsap_missing_mandatory_element);
+    /* Location area identifier Location area identifier 9.4.11 O   TLV 7 */
+    ELEM_OPT_TLV(0x04, GSM_A_PDU_TYPE_COMMON, DE_LAI, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.11 SGsAP-LOCATION-UPDATE-REQUEST message
+ */
+
+static void
+sgsap_imsi_loc_update_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* MME name MME name 9.4.13 M   TLV 57 */
+    ELEM_MAND_TLV(0x09, SGSAP_PDU_TYPE, DE_SGSAP_MME_NAME, NULL, ei_sgsap_missing_mandatory_element);
+    /* EPS location update type EPS location update type 9.4.2  M   TLV 3 */
+    ELEM_MAND_TLV(0x0a, SGSAP_PDU_TYPE, DE_SGSAP_EPS_LOC_UPD_TYPE, NULL, ei_sgsap_missing_mandatory_element);
+    /* New location area identifier Location area identifier 9.4.11 M   TLV 7 */
+    ELEM_MAND_TLV(0x04, GSM_A_PDU_TYPE_COMMON, DE_LAI, NULL, ei_sgsap_missing_mandatory_element);
+    /* Old location area identifier Location area identifier 9.4.11 O   TLV 7 */
+    ELEM_OPT_TLV(0x04, GSM_A_PDU_TYPE_COMMON, DE_LAI, " - Old location area identifier");
+    /* TMSI status  TMSI status 9.4.21  O   TLV 3 */
+    ELEM_OPT_TLV( 0x07 , GSM_A_PDU_TYPE_GM, DE_TMSI_STAT , NULL );
+    /* IMEISV   IMEISV 9.4.5    O   TLV 10 */
+    ELEM_OPT_TLV(0x15, SGSAP_PDU_TYPE, DE_SGSAP_IMEISV, NULL);
+    /* TAI Tracking Area Identity 9.4.21a O TLV 7 */
+    ELEM_OPT_TLV(0x23, NAS_PDU_TYPE_EMM, DE_EMM_TRAC_AREA_ID, NULL);
+    /* E-CGI E-UTRAN Cell Global Identity 9.4.3a O TLV 9 */
+    ELEM_OPT_TLV(0x24, SGSAP_PDU_TYPE, DE_SGSAP_ECGI, NULL);
+    /* TMSI based NRI container TMSI based NRI container 9.4.26 O TLV 4 */
+    ELEM_OPT_TLV(0x27, GSM_A_PDU_TYPE_GM, DE_NET_RES_ID_CONT, " - TMSI based NRI container");
+    /* Selected CS domain operator Selected CS domain operator 9.4.27 O TLV 5 */
+    ELEM_OPT_TLV(0x28, SGSAP_PDU_TYPE, DE_SGSAP_SELECTED_CS_DMN_OP, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.12 SGsAP-MM-INFORMATION-REQUEST
+ */
+static void
+sgsap_mm_info_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* MM information   MM information 9.4.12   M   TLV 3-n */
+    ELEM_MAND_TLV(0x17, SGSAP_PDU_TYPE, DE_SGSAP_MM_INFO, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.13 SGsAP-PAGING-REJECT message
+ */
+static void
+sgsap_paging_rej(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* SGs Cause    SGs Cause 9.4.18    M   TLV 3 */
+    ELEM_MAND_TLV(0x08, SGSAP_PDU_TYPE, DE_SGSAP_SGS_CAUSE, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.14 SGsAP-PAGING-REQUEST message
+ */
+static void
+sgsap_paging_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* VLR name VLR name 9.4.22 M   TLV 3-n */
+    ELEM_MAND_TLV(0x02, SGSAP_PDU_TYPE, DE_SGSAP_VLR_NAME, NULL, ei_sgsap_missing_mandatory_element);
+    /* Service indicator    Service indicator 9.4.17    M   TLV 3 */
+    ELEM_MAND_TLV(0x20, SGSAP_PDU_TYPE, DE_SGSAP_SERV_INDIC, NULL, ei_sgsap_missing_mandatory_element);
+    /* TMSI TMSI 9.4.20 O   TLV 6 */
+    ELEM_OPT_TLV(0x03, GSM_A_PDU_TYPE_BSSMAP, BE_TMSI, NULL);
+    /* CLI  CLI 9.4.1   O   TLV 3-14 */
+    ELEM_OPT_TLV(0x1c, GSM_A_PDU_TYPE_DTAP, DE_CLG_PARTY_BCD_NUM, " - CLI");
+    /* Location area identifier Location area identifier 9.4.11 O   TLV 7 */
+    ELEM_OPT_TLV(0x04, GSM_A_PDU_TYPE_COMMON, DE_LAI, NULL);
+    /* Global CN-Id Global CN-Id 9.4.4  O   TLV 7 */
+    ELEM_OPT_TLV(0x0b, SGSAP_PDU_TYPE, DE_SGSAP_GLOBAL_CN_ID, NULL);
+    /* SS code  SS code 9.4.19  O   TLV 3 */
+    ELEM_OPT_TLV(0x1f, NAS_PDU_TYPE_EMM, DE_EMM_SS_CODE, NULL);
+    /* LCS indicator    LCS indicator 9.4.10    O   TLV 3 */
+    ELEM_OPT_TLV(0x1e, SGSAP_PDU_TYPE, DE_SGSAP_LCS_INDIC, NULL);
+    /* LCS client identity  LCS client identity 9.4.9   O   TLV 3-n */
+    ELEM_OPT_TLV(0x1d, NAS_PDU_TYPE_EMM, DE_EMM_LCS_CLIENT_ID, NULL);
+    /* Channel needed   Channel needed 9.4.23   O   TLV 3 */
+    ELEM_OPT_TLV(0x05, GSM_A_PDU_TYPE_BSSMAP, BE_CHAN_NEEDED, NULL);
+    /* eMLPP Priority   eMLPP Priority 9.4.24   O   TLV 3 */
+    ELEM_OPT_TLV(0x06, GSM_A_PDU_TYPE_BSSMAP, BE_EMLPP_PRIO, NULL);
+    /* Additional paging indicators Additional paging indicators 9.4.25 O TLV 3 */
+    ELEM_OPT_TLV(0x26, SGSAP_PDU_TYPE, DE_SGSAP_ADD_PAGING_IND, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.15 SGsAP-RESET-ACK message
+ */
+static void
+sgsap_reset_ack(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* MME name MME name 9.4.13 C   TLV 57 */
+    ELEM_OPT_TLV(0x09, SGSAP_PDU_TYPE, DE_SGSAP_MME_NAME, NULL);
+    /* VLR name VLR name 9.4.22 C   TLV 3-n */
+    ELEM_OPT_TLV(0x02, SGSAP_PDU_TYPE, DE_SGSAP_VLR_NAME, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.16 SGsAP-RESET-INDICATION message
+ */
+static void
+sgsap_reset_ind(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* MME name MME name 9.4.13 C   TLV 57 */
+    ELEM_OPT_TLV(0x09, SGSAP_PDU_TYPE, DE_SGSAP_MME_NAME, NULL);
+    /* VLR name VLR name 9.4.22 C   TLV 3-n */
+    ELEM_OPT_TLV(0x02, SGSAP_PDU_TYPE, DE_SGSAP_VLR_NAME, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.17 SGsAP-SERVICE-REQUEST message
+ */
+static void
+sgsap_service_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /*IMSI  IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* Service indicator    Service indicator 9.4.17    M   TLV 3 */
+    ELEM_MAND_TLV(0x20, SGSAP_PDU_TYPE, DE_SGSAP_SERV_INDIC, NULL, ei_sgsap_missing_mandatory_element);
+    /* IMEISV   IMEISV 9.4.5    O   TLV 10 */
+    ELEM_OPT_TLV(0x15, SGSAP_PDU_TYPE, DE_SGSAP_IMEISV, NULL);
+    /* UE Time Zone UE Time Zone 9.4.21b    O   TLV 3 */
+    ELEM_OPT_TLV(0x21, GSM_A_PDU_TYPE_DTAP, DE_TIME_ZONE, " - UE Time Zone");
+    /* Mobile Station Classmark 2   Mobile Station Classmark 2 9.4.14a  O   TLV 5 */
+    ELEM_OPT_TLV(0x22 , GSM_A_PDU_TYPE_COMMON, DE_MS_CM_2, NULL);
+    /* TAI  Tracking Area Identity 9.4.21a  O   TLV 7 */
+    ELEM_OPT_TLV(0x23, NAS_PDU_TYPE_EMM, DE_EMM_TRAC_AREA_ID, NULL);
+    /* E-CGI    E-UTRAN Cell Global Identity 9.4.3a O   TLV 9 */
+    ELEM_OPT_TLV(0x24, SGSAP_PDU_TYPE, DE_SGSAP_ECGI, NULL);
+    /* UE EMM Mode  UE EMM mode 9.4.21c O   TLV 3 */
+    ELEM_OPT_TLV(0x25, SGSAP_PDU_TYPE, DE_SGSAP_UE_EMM_MODE, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.18 SGsAP-STATUS message
+ */
+static void
+sgsap_status(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  O   TLV 6-10 */
+    ELEM_OPT_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL);
+    /* SGs cause    SGs cause 9.4.18    M   TLV 3 */
+    ELEM_MAND_TLV(0x08, SGSAP_PDU_TYPE, DE_SGSAP_SGS_CAUSE, NULL, ei_sgsap_missing_mandatory_element);
+    /* Erroneous message    Erroneous message 9.4.3 M   TLV 3-n */
+    ELEM_OPT_TLV(0x1b, SGSAP_PDU_TYPE, DE_SGSAP_ERR_MSG, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.19 SGsAP-TMSI-REALLOCATION-COMPLETE message
+ */
+static void
+sgsap_tmsi_realloc_comp(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /*IMSI  IMSI 9.4.6  M   TLV 6-10  */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.20 SGsAP-UE-ACTIVITY-INDICATION message
+ */
+static void
+sgsap_ue_act_ind(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.21 SGsAP-UE-UNREACHABLE message
+ */
+static void
+sgsap_ue_unreachable(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* SGs cause    SGs cause 9.4.18    M   TLV 3 */
+    ELEM_MAND_TLV(0x08, SGSAP_PDU_TYPE, DE_SGSAP_SGS_CAUSE, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.22 SGsAP-UPLINK-UNITDATA message
+ */
+static void
+sgsap_ue_ul_unitdata(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* NAS message container    NAS message container 9.4.15    M   TLV 4-253 */
+    ELEM_MAND_TLV(0x16, SGSAP_PDU_TYPE, DE_SGSAP_NAS_MSG_CONTAINER, NULL, ei_sgsap_missing_mandatory_element);
+    /* IMEISV   IMEISV 9.4.5    O   TLV 10 */
+    ELEM_OPT_TLV(0x15, SGSAP_PDU_TYPE, DE_SGSAP_IMEISV, NULL);
+    /* UE Time Zone UE Time Zone 9.4.21b    O   TLV 3 */
+    ELEM_OPT_TLV(0x21, GSM_A_PDU_TYPE_DTAP, DE_TIME_ZONE, " - UE Time Zone");
+    /* Mobile Station Classmark 2   Mobile Station Classmark 2 9.4.14a  O   TLV 5 */
+    ELEM_OPT_TLV(0x22 , GSM_A_PDU_TYPE_COMMON, DE_MS_CM_2, NULL);
+    /* TAI  Tracking Area Identity 9.4.21a  O   TLV 7 */
+    ELEM_OPT_TLV(0x23, NAS_PDU_TYPE_EMM, DE_EMM_TRAC_AREA_ID, NULL);
+    /* E-CGI    E-UTRAN Cell Global Identity 9.4.3a O   TLV 9 */
+    ELEM_OPT_TLV(0x24, SGSAP_PDU_TYPE, DE_SGSAP_ECGI, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 8.23 SGsAP-RELEASE-REQUEST message
+ */
+static void
+sgsap_release_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* SGs cause    SGs cause 9.4.18    O   TLV 3 */
+    ELEM_OPT_TLV(0x08, SGSAP_PDU_TYPE, DE_SGSAP_SGS_CAUSE, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.24 SGsAP-SERVICE-ABORT-REQUEST message
+ */
+static void
+sgsap_service_abort_req(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6  M   TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+
+/*
+ * 8.25 SGsAP-MO-CSFB-INDICATION message
+ */
+static void
+sgsap_mo_csfb_ind(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len)
+{
+    guint32 curr_offset;
+    guint32 consumed;
+    guint   curr_len;
+
+    curr_offset = offset;
+    curr_len    = len;
+
+    /* IMSI IMSI 9.4.6 M TLV 6-10 */
+    ELEM_MAND_TLV(0x01, GSM_A_PDU_TYPE_BSSMAP, BE_IMSI, NULL, ei_sgsap_missing_mandatory_element);
+    /* TAI Tracking Area Identity 9.4.21a O TLV 7 */
+    ELEM_OPT_TLV(0x23, NAS_PDU_TYPE_EMM, DE_EMM_TRAC_AREA_ID, NULL);
+    /* E-CGI E-UTRAN Cell Global Identity 9.4.3a O TLV 9 */
+    ELEM_OPT_TLV(0x24, SGSAP_PDU_TYPE, DE_SGSAP_ECGI, NULL);
+
+    EXTRANEOUS_DATA_CHECK(curr_len, 0, pinfo, &ei_sgsap_extraneous_data);
+}
+/*
+ * 9.2  Message type
+ */
+static const value_string sgsap_msg_strings[] = {
+    { 0x01, "SGsAP-PAGING-REQUEST"},                /*  8.14 */
+    { 0x02, "SGsAP-PAGING-REJECT"},                 /*  8.13 */
+/*
+ * 0 0 0 0 0 0 1 1
+ * to
+ * 0 0 0 0 0 1 0 1
+ * Unassigned: treated as an unknown Message type
+ */
+    { 0x03, "Unassigned"},                          /* 7 */
+    { 0x04, "Unassigned"},                          /* 7 */
+    { 0x05, "Unassigned"},                          /* 7 */
+
+    { 0x06, "SGsAP-SERVICE-REQUEST"},               /* 8.17 */
+    { 0x07, "SGsAP-DOWNLINK-UNITDATA"},             /* 8.4 */
+    { 0x08, "SGsAP-UPLINK-UNITDATA"},               /* 8.22 */
+    { 0x09, "SGsAP-LOCATION-UPDATE-REQUEST"},       /* 8.11 */
+    { 0x0a, "SGsAP-LOCATION-UPDATE-ACCEPT"},        /* 8.9 */
+    { 0x0b, "SGsAP-LOCATION-UPDATE-REJECT"},        /* 8.10 */
+    { 0x0c, "SGsAP-TMSI-REALLOCATION-COMPLETE"},    /* 8.19 */
+    { 0x0d, "SGsAP-ALERT-REQUEST"},                 /* 8.3 */
+    { 0x0e, "SGsAP-ALERT-ACK"},                     /* 8.1 */
+    { 0x0f, "SGsAP-ALERT-REJECT"},                  /* 8.2 */
+    { 0x10, "SGsAP-UE-ACTIVITY-INDICATION"},        /* 8.20 */
+    { 0x11, "SGsAP-EPS-DETACH-INDICATION"},         /* 8.6 */
+    { 0x12, "SGsAP-EPS-DETACH-ACK"},                /* 8.5 */
+    { 0x13, "SGsAP-IMSI-DETACH-INDICATION"},        /* 8.8 */
+    { 0x14, "SGsAP-IMSI-DETACH-ACK"},               /* 8.7 */
+    { 0x15, "SGsAP-RESET-INDICATION"},              /* 8.16 */
+    { 0x16, "SGsAP-RESET-ACK"},                     /* 8.15 */
+    { 0x17, "SGsAP-SERVICE-ABORT-REQUEST"},         /* 8.24 */
+    { 0x18, "SGsAP-MO-CSFB-INDICATION"},            /* 8.25 */
+/*
+ * 0 0 0 1 1 0 0 0
+ * to
+ * 0 0 0 1 1 0 0 1
+ * Unassigned: treated as an unknown Message type
+ */
+    { 0x19, "Unassigned"},
+
+    { 0x1a, "SGsAP-MM-INFORMATION-REQUEST"},        /* 8.12 */
+    { 0x1b, "SGsAP-RELEASE-REQUEST"},               /* 8.23 */
+/*
+ * 0 0 0 1 1 1 0 0  Unassigned: treated as an unknown Message type  7
+ */
+    { 0x1c, "Unassigned"},                          /* 7 */
+
+    { 0x1d, "SGsAP-STATUS"},                        /* 8.18 */
+    { 0x1e, "Unassigned"},                          /* 7 */
+    { 0x1f, "SGsAP-UE-UNREACHABLE"},                /* 8.21 */
+    { 0,    NULL }
+};
+static value_string_ext sgsap_msg_strings_ext = VALUE_STRING_EXT_INIT(sgsap_msg_strings);
+
+#define NUM_SGSAP_MSG (sizeof(sgsap_msg_strings)/sizeof(value_string))
+static gint ett_sgsap_msg[NUM_SGSAP_MSG];
+static void (*sgsap_msg_fcn[])(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo _U_, guint32 offset, guint len) = {
+    sgsap_paging_req,           /* 0x01,    "SGsAP-PAGING-REQUEST"  8.14 */
+    sgsap_paging_rej,           /* 0x02,    "SGsAP-PAGING-REJECT"   8.13 */
+/*
+ * 0 0 0 0 0 0 1 1
+ * to
+ * 0 0 0 0 0 1 0 1
+ * Unassigned: treated as an unknown Message type
+ */
+    NULL,                           /* 0x03,    "Unassigned" 7 */
+    NULL,                           /* 0x04,    "Unassigned" 7 */
+    NULL,                           /* 0x05,    "Unassigned" 7 */
+
+    sgsap_service_req,              /* 0x06,    "SGsAP-SERVICE-REQUEST" 8.17 */
+    sgsap_dl_unitdata,              /* 0x07,    "SGsAP-DOWNLINK-UNITDATA" 8.4 */
+    sgsap_ue_ul_unitdata,           /* 0x08,    "SGsAP-UPLINK-UNITDATA" 8.22 */
+    sgsap_imsi_loc_update_req,      /* 0x09,    "SGsAP-LOCATION-UPDATE-REQUEST" 8.11 */
+    sgsap_imsi_loc_update_acc,      /* 0x0a,    "SGsAP-LOCATION-UPDATE-ACCEPT" 8.9 */
+    sgsap_imsi_loc_update_rej,      /* 0x0b,    "SGsAP-LOCATION-UPDATE-REJECT" 8.10 */
+    sgsap_tmsi_realloc_comp,        /* 0x0c,    "SGsAP-TMSI-REALLOCATION-COMPLETE"  8.19 */
+    sgsap_alert_req,                /* 0x0d,    "SGsAP-ALERT-REQUEST" 8.3 */
+    sgsap_alert_ack,                /* 0x0e,    "SGsAP-ALERT-ACK" 8.1 */
+    sgsap_alert_rej,                /* 0x0f,    "SGsAP-ALERT-REJECT" 8.2 */
+    sgsap_ue_act_ind,               /* 0x10,    "SGsAP-UE-ACTIVITY-INDICATION" 8.20 */
+    sgsap_eps_det_ind,              /* 0x11,    "SGsAP-EPS-DETACH-INDICATION" 8.6 */
+    sgsap_eps_det_ack,              /* 0x12,    "SGsAP-EPS-DETACH-ACK" 8.5 */
+    sgsap_imsi_det_ind,             /* 0x13,    "SGsAP-IMSI-DETACH-INDICATION" 8.8 */
+    sgsap_imsi_det_ack,             /* 0x14,    "SGsAP-IMSI-DETACH-ACK" 8.7 */
+    sgsap_reset_ind,                /* 0x15,    "SGsAP-RESET-INDICATION" 8.16 */
+    sgsap_reset_ack,                /* 0x16,    "SGsAP-RESET-ACK" 8.15 */
+    sgsap_service_abort_req,        /* 0x17,    "SGsAP-SERVICE-ABORT-REQUEST" 8.24 */
+    sgsap_mo_csfb_ind,              /* 0x18,    "SGsAP-MO-CSFB-INDICATION" 8.25 */
+/*
+ * 0 0 0 1 1 0 0 1
+ * to
+ * 0 0 0 1 1 0 0 1
+ * Unassigned: treated as an unknown Message type
+ */
+    NULL,                           /* 0x19,    "Unassigned" */
+
+    sgsap_mm_info_req,              /* 0x1a,    "SGsAP-MM-INFORMATION-REQUEST" 8.12 */
+    sgsap_release_req,              /* 0x1b,    "SGsAP-RELEASE-REQUEST" 8.23 */
+/*
+ * 0 0 0 1 1 1 0 0  Unassigned: treated as an unknown Message type  7
+ */
+    NULL,                           /* 0x1c,    "Unassigned" */
+
+    sgsap_status,                   /* 0x1d,    "SGsAP-STATUS" 8.18 */
+    NULL,                           /* 0x1e,    "Unassigned" */
+    sgsap_ue_unreachable,           /* 0x1f,    "SGsAP-UE-UNREACHABLE" 8.21 */
+
+    NULL,   /* NONE */
+};
+
+static void get_sgsap_msg_params(guint8 oct, const gchar **msg_str, int *ett_tree, int *hf_idx, msg_fcn *msg_fcn_p)
+{
+    gint            idx;
+
+    *msg_str   = try_val_to_str_idx_ext((guint32) (oct & 0xff), &sgsap_msg_strings_ext, &idx);
+    *hf_idx    = hf_sgsap_msg_type;
+    if (*msg_str != NULL) {
+        *ett_tree  = ett_sgsap_msg[idx];
+        *msg_fcn_p = sgsap_msg_fcn[idx];
+    }
+
+    return;
+}
+
+
+static int
+dissect_sgsap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+    proto_item      *item;
+    proto_tree      *sgsap_tree;
+    int              offset = 0;
+    guint32          len;
+    const gchar     *msg_str;
+    gint             ett_tree;
+    int              hf_idx;
+    void            (*msg_fcn_p)(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, guint32 offset, guint len);
+    guint8          oct;
+
+    len = tvb_reported_length(tvb);
+
+    /* Make entry in the Protocol column on summary display */
+    col_set_str(pinfo->cinfo, COL_PROTOCOL, PSNAME);
+
+    item = proto_tree_add_item(tree, proto_sgsap, tvb, 0, -1, ENC_NA);
+    sgsap_tree = proto_item_add_subtree(item, ett_sgsap);
+
+    /* Messge type IE*/
+    oct       = tvb_get_guint8(tvb, offset);
+    msg_fcn_p = NULL;
+    ett_tree  = -1;
+    hf_idx    = -1;
+    msg_str   = NULL;
+
+    get_sgsap_msg_params(oct, &msg_str, &ett_tree, &hf_idx, &msg_fcn_p);
+
+    if (msg_str) {
+        col_add_fstr(pinfo->cinfo, COL_INFO, "%s", msg_str);
+    }else{
+        proto_tree_add_item(tree, hf_sgsap_unknown_msg, tvb, offset, 1, ENC_BIG_ENDIAN);
+        return tvb_captured_length(tvb);
+    }
+
+    /*
+     * Add SGSAP message name
+     */
+    proto_tree_add_item(sgsap_tree, hf_idx, tvb, offset, 1, ENC_BIG_ENDIAN);
+    offset++;
+
+
+    /*
+     * decode elements
+     */
+    if (msg_fcn_p == NULL)
+    {
+        proto_tree_add_item(sgsap_tree, hf_sgsap_message_elements, tvb, offset, len - offset, ENC_NA);
+    }
+    else
+    {
+        (*msg_fcn_p)(tvb, sgsap_tree, pinfo, offset, len - offset);
+    }
+
+    return tvb_captured_length(tvb);
+}
+
+
+
+void proto_register_sgsap(void) {
+    guint        i;
+    guint        last_offset;
+
+    /* List of fields */
+
+  static hf_register_info hf[] = {
+    { &hf_sgsap_msg_type,
+        { "SGSAP Message Type",    "sgsap.msg_type",
+        FT_UINT8, BASE_HEX|BASE_EXT_STRING, &sgsap_msg_strings_ext, 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_elem_id,
+        { "Element ID",    "sgsap.elem_id",
+        FT_UINT8, BASE_HEX, NULL, 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_eps_location_update_type,
+        { "EPS location update type",    "sgsap.eps_location_update_type",
+        FT_UINT8, BASE_DEC, VALS(sgsap_eps_location_update_type_values), 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_service_indicator_value,
+        { "Service indicator",    "sgsap.service_indicator",
+        FT_UINT8, BASE_DEC, VALS(sgsap_service_indicator_values), 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_sgs_cause,
+        { "SGs cause",    "sgsap.sgs_cause",
+        FT_UINT8, BASE_DEC|BASE_EXT_STRING, &sgsap_sgs_cause_values_ext, 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_ue_emm_mode,
+        { "UE EMM mode",    "sgsap.ue_emm_mode",
+        FT_UINT8, BASE_DEC, VALS(sgsap_ue_emm_mode_values), 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_eci,
+        {"ECI (E-UTRAN Cell Identifier)", "sgsap.eci",
+        FT_UINT32, BASE_DEC, NULL, 0x0fffffff,
+        NULL, HFILL}
+    },
+    { &hf_sgsap_cn_id,
+        {"CN_ID", "sgsap.cn_id",
+        FT_UINT16, BASE_DEC, NULL, 0x0,
+        NULL, HFILL}
+    },
+    { &hf_sgsap_imsi_det_eps,
+        { "IMSI detach from EPS service type",    "sgsap.imsi_det_eps",
+        FT_UINT8, BASE_DEC, VALS(sgsap_imsi_det_from_eps_serv_type_values), 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_imsi_det_non_eps,
+        { "IMSI detach from non-EPS service type",    "sgsap.imsi_det_non_eps",
+        FT_UINT8, BASE_DEC, VALS(sgsap_imsi_det_from_non_eps_serv_type_values), 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_lcs_indic,
+        { "LCS indicator",    "sgsap.lcs_indicator",
+        FT_UINT8, BASE_DEC, VALS(sgsap_lcs_indic_values), 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_mme_name,
+        {"MME name", "sgsap.mme_name",
+        FT_STRING, BASE_NONE, NULL, 0x0,
+        NULL, HFILL}
+    },
+    { &hf_sgsap_vlr_name,
+        {"VLR name", "sgsap.vlr_name",
+        FT_STRING, BASE_NONE, NULL, 0x0,
+        NULL, HFILL}
+    },
+    { &hf_sgsap_imeisv,
+        {"IMEISV", "sgsap.imeisv",
+        FT_STRING, BASE_NONE, NULL, 0x0,
+        NULL, HFILL}
+    },
+    { &hf_sgsap_unknown_msg,
+        { "Unknown message",    "sgsap.unknown_msg",
+        FT_UINT8, BASE_HEX, NULL, 0x0,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_message_elements,
+        {"Message Elements", "sgsap.message_elements",
+        FT_BYTES, BASE_NONE, NULL, 0x0,
+        NULL, HFILL}
+    },
+    { &hf_sgsap_csri,
+        {"CS restoration indicator (CSRI)", "sgsap.csri",
+        FT_BOOLEAN, 8, TFS(&tfs_set_notset), 0x01,
+        NULL, HFILL }
+    },
+    { &hf_sgsap_sel_cs_dmn_op,
+        { "Selected CS domain operator", "sgsap.sel_cs_dmn_op",
+        FT_BYTES, BASE_NONE, NULL, 0x0,
+        NULL, HFILL }
+    },
+  };
+
+    static ei_register_info ei[] = {
+        { &ei_sgsap_extraneous_data, { "sgsap.extraneous_data", PI_PROTOCOL, PI_NOTE, "Extraneous Data, dissector bug or later version spec(report to wireshark.org)", EXPFILL }},
+        { &ei_sgsap_missing_mandatory_element, { "sgsap.missing_mandatory_element", PI_PROTOCOL, PI_WARN, "Missing Mandatory element, rest of dissection is suspect", EXPFILL }},
+    };
+
+   expert_module_t* expert_sgsap;
+
+    /* Setup protocol subtree array */
+#define NUM_INDIVIDUAL_ELEMS    2
+    gint *ett[NUM_INDIVIDUAL_ELEMS +
+          NUM_SGSAP_ELEM +
+          NUM_SGSAP_MSG];
+
+    ett[0] = &ett_sgsap;
+    ett[1] = &ett_sgsap_sel_cs_dmn_op;
+
+    last_offset = NUM_INDIVIDUAL_ELEMS;
+
+    for (i=0; i < NUM_SGSAP_ELEM; i++, last_offset++)
+    {
+        ett_sgsap_elem[i] = -1;
+        ett[last_offset] = &ett_sgsap_elem[i];
+    }
+
+    for (i=0; i < NUM_SGSAP_MSG; i++, last_offset++)
+    {
+        ett_sgsap_msg[i] = -1;
+        ett[last_offset] = &ett_sgsap_msg[i];
+    }
+
+    /* Register protocol */
+    proto_sgsap = proto_register_protocol(PNAME, PSNAME, PFNAME);
+    /* Register fields and subtrees */
+    proto_register_field_array(proto_sgsap, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+    expert_sgsap = expert_register_protocol(proto_sgsap);
+    expert_register_field_array(expert_sgsap, ei, array_length(ei));
+
+    /* Register dissector */
+    sgsap_handle = register_dissector(PFNAME, dissect_sgsap, proto_sgsap);
+
+    /* sgsap_module = prefs_register_protocol(proto_sgsap, NULL); */
+
+}
+
+void
+proto_reg_handoff_sgsap(void)
+{
+    /* The registered SCTP port number for SGsAP is 29118.
+     * The payload protocol identifier to be used for SGsAP is 0.
+     */
+    gsm_a_dtap_handle = find_dissector_add_dependency("gsm_a_dtap", proto_sgsap);
+    dissector_add_uint_range_with_preference("sctp.port", SGSAP_SCTP_PORT_RANGE, sgsap_handle);
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */