/* packet-wai.c
 * Routines for WAI packet dissection
 * Based on: WAPI ISO submission - ISO/IEC JTC 1 N 9880 [ref: 1]
 *           chapter "8.1.4 WAI protocol"
 *
 * Written by Lukasz Kotasa <lukasz.kotasa@tieto.com>
 *            Lukasz Suchy  <lukasz.suchy@tieto.com>
 * Copyright 2010, Tieto.
 *
 * $Id: packet-wai.c 37086 2011-05-12 17:19:10Z cmaynard $
 *
 * 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.
 */
/* Protocol reference:
 * http://isotc.iso.org/livelink/livelink?func=ll&objId=8500308&objAction=Open&ei=nt-RTKe1IJKTjAeepLS8BQ&usg=AFQjCNEn8hlU_SfoAGkM-X48JL_BL8bptA&sig2=JOHNPrqgCMO4q0cWhAfkow
 * (chapter: 8.1.4. WAI protocol)
 */


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

#include <epan/packet.h>
#include <epan/etypes.h>
#include <epan/reassemble.h>

#define WAI_SUB_PRE_AUTHENTICATION	0x01	/* pre-authentication start */
#define WAI_SUB_STAKEY_REQ			0x02	/* STAKey request */
#define WAI_SUB_AUTH_ACTIVATION		0x03	/* authentication activation */
#define WAI_SUB_ACCESS_AUTH_REQ		0x04	/* access authentication request */
#define WAI_SUB_ACCESS_AUTH_RESP	0x05	/* access authentication response */
#define WAI_SUB_CERT_AUTH_REQ		0x06	/* certificate authentication request */
#define WAI_SUB_CERT_AUTH_RESP		0x07	/* certificate authentication response */
#define WAI_SUB_UNICAST_KEY_REQ		0x08	/* unicast key negotiation request */
#define WAI_SUB_UNICAST_KEY_RESP	0x09	/* unicast key negotiation response */
#define WAI_SUB_UNICAST_KEY_CONFIRM	0x0A	/* unicast key negotiation confirmation */
#define WAI_SUB_MULTICAST_ANNOUNCE	0x0B	/* multicast key/STAKey announcement */
#define WAI_SUB_MULTICAST_ANNOUNCE_RESP	0x0C	/* multicast key/STAKey announcement response */

#define FLAG_BIT0	0x01
#define FLAG_BIT1	0x02
#define FLAG_BIT2	0x04
#define FLAG_BIT3	0x08
#define FLAG_BIT4	0x10
#define FLAG_BIT5	0x20
#define FLAG_BIT6	0x40
#define FLAG_BIT7	0x80

static GHashTable *wai_fragment_table = NULL;
static GHashTable *wai_reassembled_table = NULL;

static int proto_wai = -1;

static gint hf_wai_version = -1;
static gint hf_wai_type = -1;
static gint hf_wai_subtype = -1;
static gint hf_wai_reserved = -1;
static gint hf_wai_length = -1;
static gint hf_wai_seq = -1;
static gint hf_wai_fragm_seq = -1;
static gint hf_wai_flag = -1;
static gint hf_wai_data = -1;
static gint hf_wai_bk_rekeying_flag = -1;
static gint hf_wai_preauthentication_flag = -1;
static gint hf_wai_certificate_flag = -1;
static gint hf_wai_optional_flag = -1;
static gint hf_wai_usk_rekeying_flag = -1;
static gint hf_wai_negotiation_flag = -1;
static gint hf_wai_revoking_flag = -1;
static gint hf_wai_reserved_flag = -1;
static gint hf_wai_cert = -1;
static gint hf_wai_cert_id = -1;
static gint hf_wai_cert_data = -1;
static gint hf_wai_cert_len = -1;
static gint hf_wai_addid = -1;
static gint hf_wai_ae_mac = -1;
static gint hf_wai_asue_mac = -1;
static gint hf_wai_bkid = -1;
static gint hf_wai_uskid = -1;
static gint hf_wai_wie = -1;
static gint hf_wai_message_auth_code = -1;
static gint hf_wai_mskid = -1;
static gint hf_wai_data_pack_num = -1;
static gint hf_wai_key_data = -1;
static gint hf_wai_key_data_len = -1;
static gint hf_wai_key_data_content = -1;
static gint hf_wai_key_ann_id = -1;
static gint hf_wai_auth_id = -1;
static gint hf_wai_identity = -1;
static gint hf_wai_identity_id = -1;
static gint hf_wai_identity_len = -1;
static gint hf_wai_identity_data = -1;
static gint hf_wai_ecdh = -1;
static gint hf_wai_ecdh_id = -1;
static gint hf_wai_ecdh_len = -1;
static gint hf_wai_ecdh_content = -1;
static gint hf_wai_counter = -1;
static gint hf_wai_sta_key_id = -1;
static gint hf_wai_challenge = -1;
static gint hf_wai_cert_ver = -1;
static gint hf_wai_nonce = -1;
static gint hf_wai_ver_res = -1;
static gint hf_wai_sign_alg = -1;
static gint hf_wai_hash_alg_id = -1;
static gint hf_wai_sign_alg_id = -1;
static gint hf_wai_param = -1;
static gint hf_wai_param_id = -1;
static gint hf_wai_param_content = -1;
static gint hf_wai_sign_val = -1;
static gint hf_wai_sign_content = -1;
static gint hf_wai_sign = -1;
static gint hf_wai_identity_list = -1;
static gint hf_wai_reserved_byte = -1;
static gint hf_wai_no_of_ids = -1;
static gint hf_wai_access_res = -1;
static gint hf_wai_fragments = -1;
static gint hf_wai_fragment = -1;
static gint hf_wai_fragment_overlap = -1;
static gint hf_wai_fragment_overlap_conflicts = -1;
static gint hf_wai_fragment_multiple_tails = -1;
static gint hf_wai_fragment_too_long_fragment = -1;
static gint hf_wai_fragment_error = -1;
static gint hf_wai_fragment_count = -1;
static gint hf_wai_reassembled_in = -1;
static gint hf_wai_reassembled_length = -1;

static gint ett_wai = -1;
static gint ett_wai_data = -1;
static gint ett_wai_flags = -1;
static gint ett_wai_certificate = -1;
static gint ett_wai_mac = -1;
static gint ett_wai_identity = -1;
static gint ett_wai_key_data = -1;
static gint ett_wai_ecdh_param = -1;
static gint ett_wai_certificate_verification = -1;
static gint ett_wai_identity_list = -1;
static gint ett_wai_sign = -1;
static gint ett_wai_sign_alg = -1;
static gint ett_wai_sign_val = -1;
static gint ett_wai_parameter = -1;
static gint ett_wai_fragment = -1;
static gint ett_wai_fragments = -1;

static dissector_handle_t data_handle;

static const value_string wai_type_names [] = {
    { 1, "WAI protocol package"},
    { 0, NULL }
};

static const fragment_items wai_frag_items = {
    /* Fragment subtrees */
    &ett_wai_fragment,
    &ett_wai_fragments,
    /* Fragment fields */
    &hf_wai_fragments,
    &hf_wai_fragment,
    &hf_wai_fragment_overlap,
    &hf_wai_fragment_overlap_conflicts,
    &hf_wai_fragment_multiple_tails,
    &hf_wai_fragment_too_long_fragment,
    &hf_wai_fragment_error,
    &hf_wai_fragment_count,
    /* Reassembled in field */
    &hf_wai_reassembled_in,
    /* Reassembled length field */
    &hf_wai_reassembled_length,
    /* Tag */
    "Message fragments"
};

static const value_string wai_subtype_names[] = {
    {  WAI_SUB_PRE_AUTHENTICATION,	"Pre-Authentication start" },
    {  WAI_SUB_STAKEY_REQ,		"STAKey request" },
    {  WAI_SUB_AUTH_ACTIVATION,		"Authentication activation" },
    {  WAI_SUB_ACCESS_AUTH_REQ,		"Access authentication request" },
    {  WAI_SUB_ACCESS_AUTH_RESP,	"Access authentication response" },
    {  WAI_SUB_CERT_AUTH_REQ,		"Certificate authentication request" },
    {  WAI_SUB_CERT_AUTH_RESP,		"Certificate authentication response" },
    {  WAI_SUB_UNICAST_KEY_REQ,		"Unicast key negotiation request" },
    {  WAI_SUB_UNICAST_KEY_RESP,	"Unicast key negotiation response" },
    {  WAI_SUB_UNICAST_KEY_CONFIRM,	"Unicast key negotiation confirmation" },
    {  WAI_SUB_MULTICAST_ANNOUNCE,	"Multicast key/STAKey announcement" },
    {  WAI_SUB_MULTICAST_ANNOUNCE_RESP,	"Multicast key/STAKey announcement response" },
    { 0, NULL }
};

static const true_false_string wai_bk_rekeying_flag = {
    "Packet is a BK rekeying packet",
    "Packet is not a BK rekeying packet"
};

static const true_false_string wai_preauthentication_flag = {
    "Packet is a pre-authentication packet",
    "Packet is not a pre-authentication packet"
};

static const true_false_string  wai_certificate_flag = {
    "STA requires to verify the peers certificate",
    "STA doesn't require to verify the peers certificate"
};

static const true_false_string  wai_optional_flag = {
    "There are some optional fields in packet",
    "No optional fields in packet"
};

static const true_false_string  wai_usk_rekeying_flag = {
    "Packet is a USK rekeying packet",
    "Packet is not a USK rekeying packet"
};

static const true_false_string  wai_negotiation_flag = {
    "Packet is a STAKey negotiation packet",
    "Packet is not a STAKey negotiation packet"
};

static const true_false_string  wai_revoking_flag = {
    "STA delete a STAKey",
    "STA doesn't delete a STAKey"
};

static const true_false_string  wai_reserved_flag = {
    "reserved 1",
    "reserved 0"
};

static void
dissect_flag(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_item	*flag_item;
    proto_tree	*flag_tree;

    flag_item = proto_tree_add_item(tree, hf_wai_flag, tvb, offset, 1, FALSE);
    flag_tree = proto_item_add_subtree (flag_item, ett_wai_flags);

    proto_tree_add_item (flag_tree, hf_wai_bk_rekeying_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_preauthentication_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_certificate_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_optional_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_usk_rekeying_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_negotiation_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_revoking_flag, tvb, offset, 1, FALSE);
    proto_tree_add_item (flag_tree, hf_wai_reserved_flag, tvb, offset, 1, FALSE);
}

inline static void
dissect_bkid(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_bkid, tvb, offset, 16, FALSE);
}

inline static void
dissect_uskid(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_uskid, tvb, offset, 1, FALSE);
}

inline static void dissect_wie(tvbuff_t *tvb, guint offset, guint length, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_wie, tvb, offset, length, FALSE);
}

inline static void
dissect_message_auth_code(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_message_auth_code, tvb, offset, 20, FALSE);
}

inline static void
dissect_mskid(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_mskid, tvb, offset, 1, FALSE);
}

inline static void
dissect_key_announcement_identifier(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_key_ann_id, tvb, offset, 16, FALSE);
}

inline static void
dissect_counter(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_counter, tvb, offset, 16, FALSE);
}

inline static void
dissect_authentication_id(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_tree_add_item(tree, hf_wai_auth_id, tvb, offset, 32, FALSE);
}

static void
dissect_addid(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_item	*mac_item;
    proto_tree	*mac_tree;

    mac_item = proto_tree_add_string(tree, hf_wai_addid, tvb, offset, 12, "AE MAC and ASUE MAC addresses");

    mac_tree = proto_item_add_subtree(mac_item, ett_wai_mac);
    proto_tree_add_item(mac_tree, hf_wai_ae_mac, tvb, offset, 6, FALSE);
    proto_tree_add_item(mac_tree, hf_wai_asue_mac, tvb, offset+6, 6, FALSE);
}

static guint16
dissect_identity(tvbuff_t * tvb, const guint16 offset, proto_tree * tree,
   const char * const label)
{
    proto_tree	*id_tree;
    proto_item	*id_item;
    guint16	length;

    length = tvb_get_ntohs(tvb, offset+2);

    id_item = proto_tree_add_item(tree, hf_wai_identity, tvb, offset, length+4, FALSE);
    id_tree = proto_item_add_subtree(id_item, ett_wai_identity);
    proto_item_set_text(id_item, "%sIdentity", ((label==NULL)?"":label));
    proto_tree_add_item(id_tree, hf_wai_identity_id, tvb, offset, 2, FALSE);
    proto_tree_add_item(id_tree, hf_wai_identity_len, tvb, offset+2, 2, FALSE);
    proto_tree_add_item(id_tree, hf_wai_identity_data, tvb, offset+4, length, FALSE);

    return length + 4;
}

static gint16
dissect_certificate(tvbuff_t * tvb, const gint offset, proto_tree * tree,
                    const gchar * const label)
{
    proto_item	*certificate_item;
    proto_tree	*certificate_tree;
    proto_item	*id_item;
    guint16	length;
    guint16	id;
    const gchar	*id_name = "unknown";

    id = tvb_get_ntohs(tvb, offset);

    if (id == 1) {
        id_name = "X.509 v3";
    } else if (id == 2){
        id_name = "GBW";
    }

    length = tvb_get_ntohs(tvb, offset+2);

    certificate_item = proto_tree_add_item(tree, hf_wai_cert, tvb, offset, length+4, FALSE);
    proto_item_set_text(certificate_item, "%sCertificate",  ((label==NULL)?"":label));
    certificate_tree = proto_item_add_subtree(certificate_item, ett_wai_certificate);

    id_item = proto_tree_add_item(certificate_tree, hf_wai_cert_id, tvb, offset, 2, FALSE);
    proto_item_set_text(id_item, "Certificate Identifier: %s (%#x)", id_name, id);
    proto_tree_add_item(certificate_tree, hf_wai_cert_len, tvb, offset+2, 2, FALSE);
    proto_tree_add_item(certificate_tree, hf_wai_cert_data, tvb, offset+4, length, FALSE);

    return length + 4;
}

static guint16
dissect_ecdh_parameter(tvbuff_t * tvb, const gint offset, proto_tree * tree)
{
    proto_item	*ecdh_item;
    proto_tree	*ecdh_tree;
    proto_item	*ecdh_id_item;
    guint8	ecdh_id;
    guint16	ecdh_len;
    const gchar	*id_name = "unknown";

    ecdh_id = tvb_get_guint8(tvb, offset);

    if (ecdh_id == 1) {
        id_name = "OID";
    } else if (ecdh_id == 2) {
        id_name = "Detailed parameter";
    }

    ecdh_len = tvb_get_ntohs(tvb, offset+1);

    ecdh_item = proto_tree_add_item(tree, hf_wai_ecdh, tvb, offset, ecdh_len+3, FALSE);
    ecdh_tree = proto_item_add_subtree(ecdh_item, ett_wai_ecdh_param);
    ecdh_id_item = proto_tree_add_item(ecdh_tree, hf_wai_ecdh_id, tvb, offset, 1, FALSE);
    proto_item_set_text(ecdh_id_item, "ID: %s (%#x)", id_name, ecdh_id);
    proto_tree_add_item(ecdh_tree, hf_wai_ecdh_len, tvb, offset+1, 2, FALSE);
    proto_tree_add_item(ecdh_tree, hf_wai_ecdh_content, tvb, offset+3, ecdh_len, FALSE);

    return ecdh_len + 3;
}

static guint16
dissect_challenge(tvbuff_t *tvb, guint offset, proto_tree *tree, const gchar * const label)
{
    proto_item		*challenge_item;
    const guint16	challenge_length = 32;

    challenge_item = proto_tree_add_item(tree, hf_wai_challenge, tvb, offset, 32, FALSE);
    proto_item_append_text(challenge_item, "(%schallenge)",  ((label==NULL)?"":label));

    return challenge_length;
}

static guint16
dissect_key_data(tvbuff_t *tvb, guint offset, proto_tree *tree, const gchar *const label)
{
    proto_item	*key_data_item;
    proto_tree	*key_data_tree;
    guint8	length;

    length = tvb_get_guint8(tvb, offset);

    key_data_item = proto_tree_add_item(tree, hf_wai_key_data, tvb, offset, length+1, FALSE);
    proto_item_set_text(key_data_item, "%sKey Data", ((label==NULL)?"":label));
    key_data_tree = proto_item_add_subtree(key_data_item, ett_wai_key_data);
    proto_tree_add_item(key_data_tree, hf_wai_key_data_len, tvb, offset, 1, FALSE);

    if (length > 0) {
        proto_tree_add_item(key_data_tree, hf_wai_key_data_content, tvb, offset+1, length, FALSE);
    }

    return length + 1;
}

static guint
dissect_multiple_certificate(tvbuff_t * tvb, guint offset, proto_tree *tree)
{
    proto_item	*multicert_item;
    proto_tree	*multicert_tree;
    proto_item	*nonce_1_item;
    proto_item	*nonce_2_item;
    guint	length;

    length = tvb_get_ntohs(tvb, offset+1);
    multicert_item = proto_tree_add_item(tree, hf_wai_cert_ver, tvb, offset, length+3, FALSE);
    multicert_tree = proto_item_add_subtree(multicert_item, ett_wai_certificate_verification);
    proto_tree_add_item(multicert_tree, hf_wai_type, tvb, offset, 1, FALSE);
    offset++;
    proto_tree_add_item(multicert_tree, hf_wai_length, tvb, offset, 2, FALSE);
    offset += 2;
    nonce_1_item = proto_tree_add_item(multicert_tree, hf_wai_nonce, tvb, offset, 32, FALSE);
    offset += 32;
    proto_item_append_text(nonce_1_item, " 1");
    nonce_2_item = proto_tree_add_item(multicert_tree, hf_wai_nonce, tvb, offset, 32, FALSE);
    offset += 32;
    proto_item_append_text(nonce_2_item, " 2");
    proto_tree_add_item(multicert_tree, hf_wai_ver_res, tvb, offset, 1, FALSE);
    offset++;
    offset += dissect_certificate(tvb, offset, multicert_tree, "1 ");
    proto_tree_add_item(multicert_tree, hf_wai_ver_res, tvb, offset, 1, FALSE);
    offset++;
    offset += dissect_certificate(tvb, offset, multicert_tree, "2 ");

    return length + 3;
}

static guint
dissect_identity_list(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_item	*id_list_item;
    proto_tree	*id_list_tree;
    guint16	length;
    guint16	no_of_ids;
    guint16	i;

    length = tvb_get_ntohs(tvb, offset+1);
    id_list_item = proto_tree_add_item(tree, hf_wai_identity_list, tvb, offset, length+3, FALSE);
    id_list_tree = proto_item_add_subtree(id_list_item, ett_wai_identity_list);
    proto_tree_add_item(id_list_tree, hf_wai_type, tvb, offset, 1, FALSE);
    offset++;
    proto_tree_add_item(id_list_tree, hf_wai_length, tvb, offset, 2, FALSE);
    offset += 2;
    proto_tree_add_item(id_list_tree, hf_wai_reserved_byte, tvb, offset, 1, FALSE);
    offset++;
    proto_tree_add_item(id_list_tree, hf_wai_no_of_ids, tvb, offset, 2, FALSE);
    no_of_ids = tvb_get_ntohs(tvb, offset);
    offset += 2;

    for(i=0; i < no_of_ids; i++) {
        gchar number[4] = {0};

        g_snprintf(number, 4, "%d", i);
        offset += dissect_identity(tvb, offset, id_list_tree, number);
    }

    return length + 3;
}

static guint16
dissect_signature_algorithm(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_item	*sa_item;
    proto_tree	*sa_tree;
    proto_item	*param_item;
    proto_tree	*param_tree;
    proto_item	*alg_name_item;
    proto_item	*sig_name_item;
    guint16	length;
    guint8	alg_id;
    guint8	sig_id;
    guint16	param_len;

    length = tvb_get_ntohs(tvb, offset);

    sa_item = proto_tree_add_item(tree, hf_wai_sign_alg, tvb, offset,  length+2, FALSE);
    sa_tree = proto_item_add_subtree(sa_item, ett_wai_sign_alg);

    proto_tree_add_item(sa_tree, hf_wai_length, tvb, offset, 2, FALSE);
    offset += 2;

    alg_name_item = proto_tree_add_item(sa_tree, hf_wai_hash_alg_id, tvb, offset, 1, FALSE);
    alg_id = tvb_get_guint8(tvb, offset);

    if (1 == alg_id) {
        proto_item_set_text(alg_name_item, "Algorithm Idendifier: SHA-256  (0x01)");
    }

    offset += 1;
    sig_name_item = proto_tree_add_item(sa_tree, hf_wai_sign_alg_id, tvb, offset, 1, FALSE);
    sig_id = tvb_get_guint8(tvb, offset);

    if (1 == sig_id) {
        proto_item_set_text(sig_name_item, "Signature Algorithm Identifier: ECDSA-192  (0x01)");
    }

    offset += 1;
    param_len = tvb_get_ntohs(tvb, offset+1);
    param_item = proto_tree_add_item(sa_tree, hf_wai_param, tvb, offset,  param_len+3, FALSE);
    param_tree = proto_item_add_subtree(param_item, ett_wai_parameter);
    proto_tree_add_item(param_tree, hf_wai_param_id, tvb, offset, 1, FALSE);
    offset += 1;
    proto_tree_add_item(param_tree, hf_wai_length, tvb, offset, 2, FALSE);
    offset += 2;
    proto_tree_add_item(param_tree, hf_wai_param_content, tvb, offset, param_len, FALSE);

    return length + 2;
}

static guint16
dissect_signature_value(tvbuff_t *tvb, guint offset, proto_tree *tree)
{
    proto_item	*sv_item;
    proto_tree	*sv_tree;
    guint16	length = 0;

    length = tvb_get_ntohs(tvb, offset);

    sv_item = proto_tree_add_item(tree, hf_wai_sign_val, tvb, offset,  length+2, FALSE);
    sv_tree = proto_item_add_subtree(sv_item, ett_wai_sign_val);

    proto_tree_add_item(sv_tree, hf_wai_length, tvb, offset, 2, FALSE);
    offset += 2;

    proto_tree_add_item(sv_tree, hf_wai_sign_content, tvb, offset, length, FALSE);

    return length + 2;
}

static guint16
dissect_signature(tvbuff_t *tvb, guint offset, proto_tree *tree, const gchar *const label)
{
    proto_item	*ss_item;
    proto_tree	*ss_tree;
    guint	length = 0;

    length = tvb_get_ntohs(tvb, offset+1);

    ss_item = proto_tree_add_item(tree, hf_wai_sign, tvb, offset, length+3, FALSE);
    proto_item_set_text(ss_item, "%s", (label==NULL)?"Signature":label);
    ss_tree = proto_item_add_subtree(ss_item, ett_wai_sign);

    proto_tree_add_item(ss_tree, hf_wai_type, tvb, offset, 1, FALSE);
    offset++;

    proto_tree_add_item(ss_tree, hf_wai_length, tvb, offset, 2, FALSE);
    offset += 2;

    offset += dissect_identity(tvb, offset, ss_tree, NULL);
    offset += dissect_signature_algorithm(tvb, offset, ss_tree);
    offset += dissect_signature_value(tvb, offset, ss_tree);

    return length + 3;
}


static void
dissect_wai_data(tvbuff_t *tvb, proto_tree *tree, guint8 subtype, guint16 length)
{
    proto_item	*data_item;
    proto_tree	*data_tree;
    const gchar	*type_name;

    data_item = proto_tree_add_item(tree, hf_wai_data, tvb, 0, length, FALSE);
    data_tree = proto_item_add_subtree (data_item, ett_wai_data);

    type_name = val_to_str_const(subtype, wai_subtype_names, "Unknown type");

    proto_item_set_text(data_item, "%s data (%d bytes)", type_name, length);

    switch (subtype) {
        case WAI_SUB_PRE_AUTHENTICATION:
        {
            /* Chapter 8.1.4.6 Preauthentication [ref: 1] */
            dissect_flag(tvb, 0, data_tree);
            dissect_uskid(tvb, 1, data_tree);
            dissect_addid(tvb, 2, data_tree);
            dissect_counter(tvb, 14, data_tree);
            dissect_message_auth_code(tvb, 30, data_tree);
            break;
        }
        case WAI_SUB_STAKEY_REQ:
        {
            /* Chapter 8.1.4.5 STAKey Establishment procedure [ref: 1] */
            dissect_flag(tvb, 0, data_tree);
            proto_tree_add_item(data_tree, hf_wai_sta_key_id, tvb, 1, 1, FALSE);
            dissect_uskid(tvb, 2, data_tree);
            dissect_addid(tvb, 3, data_tree);
            dissect_counter(tvb, 15, data_tree);
            dissect_message_auth_code(tvb, 31, data_tree);
            break;
        }
        case WAI_SUB_AUTH_ACTIVATION:
        {
            /* Chapter 8.1.4.2.1 WAI Authentication Activation  [ref: 1] */
            guint16 offset = 0;

            dissect_flag(tvb, offset, data_tree);
            offset++;
            dissect_authentication_id(tvb, offset, data_tree);
            offset += 32;
            offset += dissect_identity(tvb, offset, data_tree, "Local ASU ");
            offset += dissect_certificate(tvb, offset, data_tree, "STE AE ");
            dissect_ecdh_parameter(tvb, offset, data_tree);
            break;
        }
        case WAI_SUB_ACCESS_AUTH_REQ:
        {
            /* Chapter 8.1.4.2.2 Access WAI Authentication Request  [ref: 1] */
            guint16 offset = 0;
            guint8  optional_field;

            optional_field = tvb_get_guint8(tvb, 0) & FLAG_BIT3;

            dissect_flag(tvb, offset, data_tree);
            offset++;
            dissect_authentication_id(tvb, offset, data_tree);
            offset += 32;
            offset += dissect_challenge(tvb, offset, data_tree, "ASUE ");
            offset += dissect_key_data(tvb, offset, data_tree, "ASUE ");
            offset += dissect_identity(tvb, offset, data_tree, "STA AE ");
            offset += dissect_certificate(tvb, offset, data_tree, "STA ASUE ");
            offset += dissect_ecdh_parameter(tvb, offset, data_tree);

            if (optional_field) {
                offset += dissect_identity_list(tvb, offset, data_tree);
            }

            dissect_signature(tvb, offset, data_tree, "ASUE Signature");
            break;
        }
        case WAI_SUB_ACCESS_AUTH_RESP:
        {
            /* Chapter 8.1.4.2.5 Access WAI Authentication Response  [ref: 1] */
            guint16 offset = 0;
            guint8  optional_field;

            optional_field = tvb_get_guint8(tvb, 0) & FLAG_BIT3;

            dissect_flag(tvb, offset, data_tree);
            offset++;
            offset += dissect_challenge(tvb, offset, data_tree, "ASUE ");
            offset += dissect_challenge(tvb, offset, data_tree, "AE ");
            proto_tree_add_item(data_tree, hf_wai_access_res, tvb, offset, 1, FALSE);
            offset++;
            offset += dissect_key_data(tvb, offset, data_tree, "ASUE ");
            offset += dissect_key_data(tvb, offset, data_tree, "AE ");
            offset += dissect_identity(tvb, offset, data_tree, "STA AE ");
            offset += dissect_identity(tvb, offset, data_tree, "STA ASUE ");

            if (optional_field) {
                offset += dissect_multiple_certificate(tvb, offset, data_tree);
            }

            offset += dissect_signature(tvb, offset, data_tree, "AE Signature");
            break;
        }
        case WAI_SUB_CERT_AUTH_REQ:
        {
            /* Chapter 8.1.4.2.3 Certificate Authentication Request  [ref: 1] */
            guint16 offset = 0;

            dissect_addid(tvb, offset, data_tree);
            offset+=12;
            offset += dissect_challenge(tvb, offset, data_tree, "AE ");
            offset += dissect_challenge(tvb, offset, data_tree, "ASUE ");
            offset += dissect_certificate(tvb, offset, data_tree, "STE ASUE ");
            offset += dissect_certificate(tvb, offset, data_tree, "STE AE ");
            offset += dissect_multiple_certificate(tvb, offset, data_tree);
            break;
        }
        case WAI_SUB_CERT_AUTH_RESP:
        {
            /* Chapter 8.1.4.2.4 Certificate Authentication Response  [ref: 1] */
            guint16 offset = 0;

            dissect_addid(tvb, offset, data_tree);
            offset += 12;
            offset += dissect_multiple_certificate(tvb, offset, data_tree);
            offset += dissect_signature(tvb, offset, data_tree, "Server Signature trusted by ASUE");
            offset += dissect_signature(tvb, offset, data_tree, "Server Signature trusted by AE");
            break;
        }
        case WAI_SUB_UNICAST_KEY_REQ:
        {
            /* Chapter 8.1.4.3.1 Unicast Key Negotiation Request [ref: 1] */
            dissect_flag(tvb, 0, data_tree);
            dissect_bkid(tvb, 1, data_tree);
            dissect_uskid(tvb, 17, data_tree);
            dissect_addid(tvb, 18, data_tree);
            dissect_challenge(tvb, 30, data_tree ,"AE ");
            break;
        }
        case WAI_SUB_UNICAST_KEY_RESP:
        {
            /* Chapter 8.1.4.3.2 Unicast Key Negotiation Response [ref: 1] */
            tvbuff_t  *next_tvb;
            guint length = 0;

            dissect_flag(tvb, 0, data_tree);
            dissect_bkid(tvb, 1, data_tree);
            dissect_uskid(tvb, 17, data_tree);
            dissect_addid(tvb, 18, data_tree);
            dissect_challenge(tvb, 30, data_tree, "ASUE ");
            dissect_challenge(tvb, 62, data_tree, "AE ");

            next_tvb = tvb_new_subset_remaining(tvb, 96);
            length = tvb_reported_length(next_tvb);

            dissect_wie(next_tvb, 0, length-20, data_tree);
            dissect_message_auth_code(next_tvb, length-20, data_tree);
            break;
        }
        case WAI_SUB_UNICAST_KEY_CONFIRM:
        {
            /* Chapter 8.1.4.3.3 Unicast Key Negotiation Confirmation [ref: 1] */
            tvbuff_t  *next_tvb;
            guint length = 0;

            dissect_flag(tvb, 0, data_tree);
            dissect_bkid(tvb, 1, data_tree);
            dissect_uskid(tvb, 17, data_tree);
            dissect_addid(tvb, 18, data_tree);
            dissect_challenge(tvb, 30, data_tree, "ASUE ");

            next_tvb = tvb_new_subset_remaining(tvb, 62);
            length = tvb_reported_length(next_tvb);

            dissect_wie(next_tvb, 0, length-20, data_tree);
            dissect_message_auth_code(next_tvb, length-20, data_tree);
            break;
        }
        case WAI_SUB_MULTICAST_ANNOUNCE:
        {
            /* Chapter 8.1.4.4.1 Multicast Key/STAKey Announcement [ref: 1] */
            guint16 offset = 0;

            dissect_flag(tvb, offset, data_tree);
            offset += 1;
            dissect_mskid(tvb, offset, data_tree);
            offset += 1;
            dissect_uskid(tvb, offset, data_tree);
            offset += 1;
            dissect_addid(tvb, offset, data_tree);
            offset += 12;
            proto_tree_add_item(data_tree, hf_wai_data_pack_num, tvb, offset, 16, FALSE);
            offset += 16;
            dissect_key_announcement_identifier(tvb, offset, data_tree);
            offset += 16;
            offset += dissect_key_data(tvb, offset, data_tree, NULL);
            dissect_message_auth_code(tvb, offset, data_tree);
            break;
        }
        case WAI_SUB_MULTICAST_ANNOUNCE_RESP:
        {
            /* Chapter 8.1.4.4.2 Multicast Key/STAKey Announcement Response [ref: 1] */
            dissect_flag(tvb, 0, data_tree);
            dissect_mskid(tvb, 1, data_tree);
            dissect_uskid(tvb, 2, data_tree);
            dissect_addid(tvb, 3, data_tree);
            dissect_key_announcement_identifier(tvb, 15, data_tree);
            dissect_message_auth_code(tvb, 31, data_tree);
            break;
        }
        default:
            break;
    }
}

static void
dissect_wai(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
/* Format of WAPI protocol packet in WAI authentication system

0      2      3         4         6         8        10        11      12
-------------------------------------------------------------------------------
| Ver. | Type | Subtype | Reserved | Length | packet  |  fragm. | flag | data |
|                                           | seq. no | seq. no |             |
|-----------------------------------------------------------------------------|
Figure 18 from [ref:1]
*/
#define WAI_MESSAGE_LENGTH	12 /*Length of all fields without 'Data' field*/
#define WAI_DATA_OFFSET 	WAI_MESSAGE_LENGTH
    guint16		version;
    guint8		type;
    guint8		subtype;
    guint16		length;
    guint16		packet_num;
    guint8		fragment_num;
    guint8		flags;
    fragment_data	*frag_msg;
    proto_tree		*wai_tree = NULL;
    tvbuff_t		*next_tvb;
    tvbuff_t		*new_tvb;
    const gchar		*subtype_name = "Unknown type";

    length = tvb_get_ntohs(tvb, 6)-WAI_MESSAGE_LENGTH;
    subtype = tvb_get_guint8(tvb, 3);

    /* quick sanity check */
    if ((length != tvb_reported_length (tvb)-WAI_MESSAGE_LENGTH) || (subtype > WAI_SUB_MULTICAST_ANNOUNCE_RESP)) {
        return;
    }

    col_set_str(pinfo->cinfo, COL_PROTOCOL, "WAI");
    col_clear (pinfo->cinfo, COL_INFO);
    version = tvb_get_ntohs(tvb, 0);

    if (version == 1) {
        subtype_name = val_to_str_const(subtype, wai_subtype_names, "Unknown type");
    }
    col_append_fstr(pinfo->cinfo, COL_INFO, "%s", subtype_name);

    /* Field lengths and offsets in WAI protocol described above */
    type = tvb_get_guint8(tvb, 2);
    packet_num = tvb_get_ntohs(tvb, 8);
    fragment_num = tvb_get_guint8(tvb, 10);
    flags = tvb_get_guint8(tvb, 11);

    if (tree) {
        proto_item	*wai_item;

        wai_item = proto_tree_add_item(tree, proto_wai, tvb, 0, -1, ENC_NA);

        proto_item_set_text (wai_item, "WAI Protocol (%s)",
        			val_to_str_const(subtype, wai_subtype_names, "Unknown type"));
        wai_tree = proto_item_add_subtree(wai_item, ett_wai);

        /* Field lengths and offsets in WAI protocol described above */
        proto_tree_add_item(wai_tree, hf_wai_version, tvb, 0, 2, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_type, tvb, 2, 1, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_subtype, tvb, 3, 1, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_reserved, tvb, 4, 2, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_length, tvb, 6,2, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_seq, tvb, 8, 2, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_fragm_seq, tvb, 10, 1, FALSE);
        proto_tree_add_item(wai_tree, hf_wai_flag, tvb, 11, 1, FALSE);
    }

    frag_msg =  fragment_add_seq_check (tvb, WAI_DATA_OFFSET, pinfo,
    					packet_num,
    					wai_fragment_table,
    					wai_reassembled_table,
    					fragment_num,
    					length,
    					flags);

    next_tvb = tvb_new_subset_remaining(tvb, WAI_DATA_OFFSET);

    /* Replace INFO column if message is fragmented and call data_handle */
    if (flags) {
        col_add_fstr(pinfo->cinfo, COL_INFO,
                     "Fragment (%d) of message, data not dissected", fragment_num);

        process_reassembled_data(tvb, WAI_DATA_OFFSET, pinfo,
                                 "Reassembled WAI", frag_msg, &wai_frag_items,
                                 NULL, wai_tree);

        call_dissector(data_handle, next_tvb, pinfo, tree);
    } else {
        /* If this is the last fragment of fragmented message, then reassamble and dissect
           otherwise only dissect */
        if (fragment_num > 0) {
            new_tvb = process_reassembled_data(tvb, WAI_DATA_OFFSET, pinfo, "Reassembled WAI", frag_msg, &wai_frag_items,
                                               NULL, wai_tree);

            if (new_tvb) {
                col_add_str(pinfo->cinfo, COL_INFO, "Last fragment of message, data dissected");
                col_append_sep_str(pinfo->cinfo, COL_INFO, ": ", subtype_name);
                next_tvb=new_tvb;
                length = tvb_reported_length (next_tvb);
            }
        }
        /* dissect Data field of WAI packet */
        if (tree) {
            dissect_wai_data(next_tvb, wai_tree, subtype, length);
        }
    }

}

static void wai_reassemble_init (void)
{
    fragment_table_init(&wai_fragment_table);
    reassembled_table_init(&wai_reassembled_table);
}

void
proto_register_wai(void)
{
    static hf_register_info hf[] = {
        { &hf_wai_version, { "Version", "wai.version", FT_UINT16, BASE_DEC, NULL,
            0x0, "Version of authentication infrastructure", HFILL }},

        { &hf_wai_type, { "Type", "wai.type", FT_UINT8, BASE_HEX, VALS(wai_type_names),
            0x0, "Protocol type", HFILL }},

        { &hf_wai_subtype, { "Subtype", "wai.subtype", FT_UINT8, BASE_DEC, VALS(wai_subtype_names),
            0x0, NULL, HFILL }},

        { &hf_wai_reserved, { "Reserved", "wai.reserved", FT_UINT16, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_length, { "Length", "wai.length", FT_UINT16, BASE_DEC, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_seq, { "Sequence number", "wai.seq", FT_UINT16, BASE_DEC, NULL,
            0x0, "Packet sequence number", HFILL }},

        { &hf_wai_fragm_seq, { "Fragment sequence number", "wai.fragm.seq", FT_UINT8, BASE_DEC, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_flag, { "Flag", "wai.flag", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_data, { "Data", "wai.data", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_bk_rekeying_flag, {"BK rekeying", "wai.bk.rekeying.flag", FT_BOOLEAN, 8, TFS (&wai_bk_rekeying_flag),
            FLAG_BIT0, "BK rekeying flag", HFILL }},

        { &hf_wai_preauthentication_flag,{"Pre-Authentication", "wai.preauthentication.flag", FT_BOOLEAN, 8, TFS (&wai_preauthentication_flag),
            FLAG_BIT1, "Pre-Authentication flag", HFILL }},

        { &hf_wai_certificate_flag,{"Certificate", "wai.certificate.flag", FT_BOOLEAN, 8, TFS (&wai_certificate_flag),
            FLAG_BIT2, "Certificate flag", HFILL }},

        { &hf_wai_optional_flag,{"Optional", "wai.optional.flag", FT_BOOLEAN, 8, TFS (&wai_optional_flag),
            FLAG_BIT3, "Optional flag", HFILL }},

        { &hf_wai_usk_rekeying_flag,{"USK rekeying", "wai.usk.rekeying.flag", FT_BOOLEAN, 8, TFS (&wai_usk_rekeying_flag),
            FLAG_BIT4, "USK rekeying flag", HFILL }},

        { &hf_wai_negotiation_flag,{"STA negotiation", "wai.negotiation.flag", FT_BOOLEAN, 8, TFS (&wai_negotiation_flag),
            FLAG_BIT5, "STA negotiation flag", HFILL }},

        { &hf_wai_revoking_flag,{"STA revoking", "wai.revoking.flag", FT_BOOLEAN, 8, TFS (&wai_revoking_flag),
            FLAG_BIT6, "STA revoking flag", HFILL }},

        { &hf_wai_reserved_flag,{"Reserved", "wai.reserved.flag", FT_BOOLEAN, 8, TFS (&wai_reserved_flag),
            FLAG_BIT7, "Reserved flag", HFILL }},

        { &hf_wai_cert, {"Certificate", "wai.cert", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_cert_id, {"Id", "wai.cert.id", FT_UINT16, BASE_HEX, NULL,
            0x0, "Certificate Id", HFILL }},

        { &hf_wai_cert_data, {"Data", "wai.cert.data", FT_BYTES, BASE_NONE, NULL,
            0x0, "Certificate data", HFILL }},

        { &hf_wai_cert_len, {"Length", "wai.cert.len", FT_UINT16, BASE_DEC, NULL,
            0x0, "Certificate length", HFILL }},

        { &hf_wai_addid, {"ADDID", "wai.addid", FT_STRING, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_ae_mac, {"AE MAC", "wai.ae.mac", FT_ETHER, BASE_NONE, NULL,
            0x0, "AE MAC address", HFILL }},

        { &hf_wai_asue_mac, {"ASUE MAC", "wai.asue.mac", FT_ETHER, BASE_NONE, NULL,
            0x0, "ASUE MAC address", HFILL }},

        { &hf_wai_bkid, {"BKID", "wai.bkid", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_uskid, {"USKID", "wai.uskid", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_wie, {"WIE from ASUE", "wai.wie", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_message_auth_code, {"Message Authentication Code", "wai.message.auth.code", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_mskid, {"MSKID/STAKeyID", "wai.mskid", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_data_pack_num, {"Data packet number", "wai.data.packet.num", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_key_data, {"Key Data", "wai.key.data", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_key_data_len, {"Length", "wai.key.data.len", FT_UINT8, BASE_DEC, NULL,
            0x0, "Key data length", HFILL }},

        { &hf_wai_key_data_content, {"Content", "wai.key.data.content", FT_BYTES, BASE_NONE, NULL,
            0x0, "Key data content", HFILL }},

        { &hf_wai_key_ann_id, {"Key Announcement Identifier", "wai.key.ann.id", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_auth_id, {"Authentication Identifier", "wai.auth.id", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_identity, {"Identifier", "wai.identity", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_identity_id, {"Id", "wai.identity.id", FT_UINT16, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_identity_len, {"Length", "wai.identity.len", FT_UINT16, BASE_DEC, NULL,
            0x0, "Identity length", HFILL }},

        { &hf_wai_identity_data, {"Data", "wai.identity.data", FT_BYTES, BASE_NONE, NULL,
            0x0, "Identity data", HFILL }},

        { &hf_wai_ecdh, {"ECDH Parameter", "wai.ecdhp", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_ecdh_id, {"ID", "wai.edch.id", FT_UINT8, BASE_HEX, NULL,
            0x0, "ECDH Parameter Identifier", HFILL }},

        { &hf_wai_ecdh_len, {"Length", "wai.ecdh.len", FT_UINT16, BASE_DEC, NULL,
            0x0, "ECDH Parameter Length", HFILL }},

        { &hf_wai_ecdh_content, {"Content", "wai.ecdh.content", FT_BYTES, BASE_NONE, NULL,
            0x0, "ECDH Parameter Content", HFILL }},

        { &hf_wai_counter, {"Replay counter", "wai.counter", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_sta_key_id, {"STAKeyID", "wai.sta.key.id", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_challenge, {"Challenge", "wai.challenge", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_cert_ver, {"Multiple Certificate Verification Result", "wai.cert.ver", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_nonce, {"Nonce", "wai.nonce", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_ver_res, {"Verification result", "wai.ver.res", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_sign_alg, {"Signature Algorithm", "wai.sign.alg", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_hash_alg_id, {"Hash Algorithm Identifier", "wai.hash.alg.id", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_sign_alg_id, {"Signature Algorithm Identifier", "wai.sign.alg.id", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_param, {"Parameter", "wai.param", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_param_id, {"Parameter Identifier", "wai.param.id", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_param_content, {"Parameter Content", "wai.param.content", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_sign_val, {"Signature Value", "wai.sign.val", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_sign_content, {"Signature Content", "wai.sign.content", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_sign, {"Signature", "wai.sign", FT_BYTES, BASE_NONE, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_identity_list, {"ASU List trusted by ASUE", "wai.identity_list", FT_BYTES, BASE_NONE, NULL,
            0x0, "Identity list", HFILL }},

        { &hf_wai_reserved_byte, {"Reserved", "wai.reserved.byte", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_no_of_ids, {"Number of Identities", "wai.no.of.ids", FT_UINT16, BASE_DEC, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_access_res, {"Access result", "wai.access_result", FT_UINT8, BASE_HEX, NULL,
            0x0, NULL, HFILL }},

        { &hf_wai_fragments,{"Message fragments", "wai.fragments",FT_NONE, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment,{"Message fragment", "wai.fragment",FT_FRAMENUM, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment_overlap,{"Message fragment overlap", "wai.fragment.overlap",FT_BOOLEAN, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment_overlap_conflicts,{"Message fragment overlapping with conflicting data","wai.fragment.overlap.conflicts",FT_BOOLEAN, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment_multiple_tails,{"Message has multiple tail fragments","wai.fragment.multiple_tails",FT_BOOLEAN, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment_too_long_fragment,{"Message fragment too long", "wai.fragment.too_long_fragment",FT_BOOLEAN, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment_error,{"Message defragmentation error", "wai.fragment.error",FT_FRAMENUM, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_fragment_count,{"Message fragment count", "wai.fragment.count",FT_UINT32, BASE_DEC, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_reassembled_in,{"Reassembled in", "wai.reassembled.in",FT_FRAMENUM, BASE_NONE, NULL,
            0x00, NULL, HFILL }},

        { &hf_wai_reassembled_length,{"Reassembled length", "wai.reassembled.length",FT_UINT32, BASE_DEC, NULL,
            0x00, NULL, HFILL }}
    };

    static gint *ett[] = {
        &ett_wai,
        &ett_wai_data,
        &ett_wai_flags,
        &ett_wai_certificate,
        &ett_wai_mac,
        &ett_wai_identity,
        &ett_wai_key_data,
        &ett_wai_ecdh_param,
        &ett_wai_certificate_verification,
        &ett_wai_identity_list,
        &ett_wai_sign,
        &ett_wai_sign_alg,
        &ett_wai_sign_val,
        &ett_wai_parameter,
        &ett_wai_fragment,
        &ett_wai_fragments
    };

    proto_wai = proto_register_protocol("WAI Protocol", "WAI", "wai");
    register_init_routine(&wai_reassemble_init);
    proto_register_field_array(proto_wai, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));
    register_dissector("wai", dissect_wai, proto_wai);
}

void
proto_reg_handoff_wai(void)
{
    dissector_handle_t wai_handle;

    data_handle = find_dissector("data");
    wai_handle  = find_dissector("wai");
    dissector_add_uint("ethertype", ETHERTYPE_WAI, wai_handle);
}
