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path: root/epan/dissectors/packet-classicstun.c
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/* packet-classicstun.c
 * Routines for Simple Traversal of UDP Through NAT dissection
 * Copyright 2003, Shiang-Ming Huang <smhuang@pcs.csie.nctu.edu.tw>
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please refer to RFC 3489 for protocol detail.
 * (supports extra message attributes described in draft-ietf-behave-rfc3489bis-00)
 */

#include "config.h"

#include <glib.h>

#include <epan/packet.h>
#include <epan/conversation.h>
#include <epan/wmem/wmem.h>

void proto_register_classicstun(void);
void proto_reg_handoff_classicstun(void);

/* Initialize the protocol and registered fields */
static int proto_classicstun                          = -1;

static int hf_classicstun_type                        = -1; /* CLASSIC-STUN message header */
static int hf_classicstun_length                      = -1;
static int hf_classicstun_id                          = -1;
static int hf_classicstun_att                         = -1;
static int hf_classicstun_response_in                 = -1;
static int hf_classicstun_response_to                 = -1;
static int hf_classicstun_time                        = -1;


static int classicstun_att_type                       = -1; /* CLASSIC-STUN attribute fields */
static int classicstun_att_length                     = -1;
static int classicstun_att_value                      = -1;
static int classicstun_att_family                     = -1;
static int classicstun_att_ipv4                       = -1;
static int classicstun_att_ipv6                       = -1;
static int classicstun_att_port                       = -1;
static int classicstun_att_change_ip                  = -1;
static int classicstun_att_change_port                = -1;
static int classicstun_att_unknown                    = -1;
static int classicstun_att_error_class                = -1;
static int classicstun_att_error_number               = -1;
static int classicstun_att_error_reason               = -1;
static int classicstun_att_server_string              = -1;
static int classicstun_att_xor_ipv4                   = -1;
static int classicstun_att_xor_ipv6                   = -1;
static int classicstun_att_xor_port                   = -1;
static int classicstun_att_lifetime                   = -1;
static int classicstun_att_magic_cookie               = -1;
static int classicstun_att_bandwidth                  = -1;
static int classicstun_att_data                       = -1;
static int classicstun_att_connection_request_binding = -1;

/* Structure containing transaction specific information */
typedef struct _classicstun_transaction_t {
    guint32  req_frame;
    guint32  rep_frame;
    nstime_t req_time;
} classicstun_transaction_t;

/* Structure containing conversation specific information */
typedef struct _classicstun_conv_info_t {
    wmem_tree_t *pdus;
} classicstun_conv_info_t;


/* Message Types */
#define BINDING_REQUEST                       0x0001
#define BINDING_RESPONSE                      0x0101
#define BINDING_ERROR_RESPONSE                0x0111
#define SHARED_SECRET_REQUEST                 0x0002
#define SHARED_SECRET_RESPONSE                0x0102
#define SHARED_SECRET_ERROR_RESPONSE          0x1112
#define ALLOCATE_REQUEST                      0x0003
#define ALLOCATE_RESPONSE                     0x0103
#define ALLOCATE_ERROR_RESPONSE               0x0113
#define SEND_REQUEST                          0x0004
#define SEND_RESPONSE                         0x0104
#define SEND_ERROR_RESPONSE                   0x0114
#define DATA_INDICATION                       0x0115
#define SET_ACTIVE_DESTINATION_REQUEST        0x0006
#define SET_ACTIVE_DESTINATION_RESPONSE       0x0106
#define SET_ACTIVE_DESTINATION_ERROR_RESPONSE 0x0116


/* Message classes */
#define CLASS_MASK                            0xC110
#define REQUEST                               0x0000
#define INDICATION                            0x0001
#define RESPONSE                              0x0010
#define ERROR_RESPONSE                        0x0011

/* Attribute Types */
#define MAPPED_ADDRESS                        0x0001
#define RESPONSE_ADDRESS                      0x0002
#define CHANGE_REQUEST                        0x0003
#define SOURCE_ADDRESS                        0x0004
#define CHANGED_ADDRESS                       0x0005
#define USERNAME                              0x0006
#define PASSWORD                              0x0007
#define MESSAGE_INTEGRITY                     0x0008
#define ERROR_CODE                            0x0009
#define UNKNOWN_ATTRIBUTES                    0x000a
#define REFLECTED_FROM                        0x000b
#define LIFETIME                              0x000d
#define ALTERNATE_SERVER                      0x000e
#define MAGIC_COOKIE                          0x000f
#define BANDWIDTH                             0x0010
#define DESTINATION_ADDRESS                   0x0011
#define REMOTE_ADDRESS                        0x0012
#define DATA                                  0x0013
#define NONCE                                 0x0014
#define REALM                                 0x0015
#define REQUESTED_ADDRESS_TYPE                0x0016
#define XOR_MAPPED_ADDRESS                    0x8020
#define XOR_ONLY                              0x0021
#define SERVER                                0x8022
#define CONNECTION_REQUEST_BINDING            0xc001
#define BINDING_CHANGE                        0xc002



/* Initialize the subtree pointers */
static gint ett_classicstun = -1;
static gint ett_classicstun_att_type = -1;
static gint ett_classicstun_att = -1;


#define UDP_PORT_STUN   3478
#define TCP_PORT_STUN   3478


#define CLASSICSTUN_HDR_LEN ((guint)20) /* CLASSIC-STUN message header length */
#define ATTR_HDR_LEN                 4  /* CLASSIC-STUN attribute header length */


static const value_string messages[] = {
    {BINDING_REQUEST                       , "Binding Request"},
    {BINDING_RESPONSE                      , "Binding Response"},
    {BINDING_ERROR_RESPONSE                , "Binding Error Response"},
    {SHARED_SECRET_REQUEST                 , "Shared Secret Request"},
    {SHARED_SECRET_RESPONSE                , "Shared Secret Response"},
    {SHARED_SECRET_ERROR_RESPONSE          , "Shared Secret Error Response"},
    {ALLOCATE_REQUEST                      , "Allocate Request"},
    {ALLOCATE_RESPONSE                     , "Allocate Response"},
    {ALLOCATE_ERROR_RESPONSE               , "Allocate Error Response"},
    {SEND_REQUEST                          , "Send Request"},
    {SEND_RESPONSE                         , "Send Response"},
    {SEND_ERROR_RESPONSE                   , "Send Error Response"},
    {DATA_INDICATION                       , "Data Indication"},
    {SET_ACTIVE_DESTINATION_REQUEST        , "Set Active Destination Request"},
    {SET_ACTIVE_DESTINATION_RESPONSE       , "Set Active Destination Response"},
    {SET_ACTIVE_DESTINATION_ERROR_RESPONSE , "Set Active Destination Error Response"},
    {0x00                                  , NULL}
};

static const value_string attributes[] = {
    {MAPPED_ADDRESS                        , "MAPPED-ADDRESS"},
    {RESPONSE_ADDRESS                      , "RESPONSE-ADDRESS"},
    {CHANGE_REQUEST                        , "CHANGE-REQUEST"},
    {SOURCE_ADDRESS                        , "SOURCE-ADDRESS"},
    {CHANGED_ADDRESS                       , "CHANGED-ADDRESS"},
    {USERNAME                              , "USERNAME"},
    {PASSWORD                              , "PASSWORD"},
    {MESSAGE_INTEGRITY                     , "MESSAGE-INTEGRITY"},
    {ERROR_CODE                            , "ERROR-CODE"},
    {REFLECTED_FROM                        , "REFLECTED-FROM"},
    {LIFETIME                              , "LIFETIME"},
    {ALTERNATE_SERVER                      , "ALTERNATE_SERVER"},
    {MAGIC_COOKIE                          , "MAGIC_COOKIE"},
    {BANDWIDTH                             , "BANDWIDTH"},
    {DESTINATION_ADDRESS                   , "DESTINATION_ADDRESS"},
    {REMOTE_ADDRESS                        , "REMOTE_ADDRESS"},
    {DATA                                  , "DATA"},
    {NONCE                                 , "NONCE"},
    {REALM                                 , "REALM"},
    {REQUESTED_ADDRESS_TYPE                , "REQUESTED_ADDRESS_TYPE"},
    {XOR_MAPPED_ADDRESS                    , "XOR_MAPPED_ADDRESS"},
    {XOR_ONLY                              , "XOR_ONLY"},
    {SERVER                                , "SERVER"},
    {CONNECTION_REQUEST_BINDING            , "CONNECTION-REQUEST-BINDING"},
    {BINDING_CHANGE                        , "BINDING-CHANGE"},
    {0x00                                  , NULL}
};

static const value_string attributes_family[] = {
    {0x0001                                , "IPv4"},
    {0x0002                                , "IPv6"},
    {0x00                                  , NULL}
};

static int
dissect_classicstun(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{

    proto_item                *ti;
    proto_item                *ta;
    proto_tree                *classicstun_tree;
    proto_tree                *att_type_tree;
    proto_tree                *att_tree;
    guint16                    msg_type;
    guint16                    msg_length;
    const char                *msg_type_str;
    guint16                    att_type;
    guint16                    att_length;
    guint16                    offset;
    guint                      len;
    guint                      i;
    conversation_t            *conversation;
    classicstun_conv_info_t   *classicstun_info;
    classicstun_transaction_t *classicstun_trans;
    wmem_tree_key_t            transaction_id_key[2];
    guint32                    transaction_id[4];


    /*
     * First check if the frame is really meant for us.
     */
    len = tvb_captured_length(tvb);
    /* First, make sure we have enough data to do the check. */
    if (len < CLASSICSTUN_HDR_LEN)
        return 0;

    msg_type = tvb_get_ntohs(tvb, 0);

    if (msg_type & 0xC000 || tvb_get_ntohl(tvb, 4) == 0x2112a442 /* New STUN */
        || tvb_get_ntohl(tvb, 4) == 0x7f5a9bc7) /* XMCP */
        return 0;

    /* check if message type is correct */
    msg_type_str = try_val_to_str(msg_type, messages);
    if (msg_type_str == NULL)
        return 0;

    msg_length = tvb_get_ntohs(tvb, 2);

    /* check if payload enough */
    if (len != CLASSICSTUN_HDR_LEN+msg_length)
        return 0;

    /* The message seems to be a valid CLASSIC-STUN message! */

    /* Create the transaction key which may be used
       to track the conversation */
    transaction_id[0] = tvb_get_ntohl(tvb, 4);
    transaction_id[1] = tvb_get_ntohl(tvb, 8);
    transaction_id[2] = tvb_get_ntohl(tvb, 12);
    transaction_id[3] = tvb_get_ntohl(tvb, 16);

    transaction_id_key[0].length = 4;
    transaction_id_key[0].key    = transaction_id;
    transaction_id_key[1].length = 0;
    transaction_id_key[1].key    = NULL;

    /*
     * Do we have a conversation for this connection?
     */
    conversation = find_or_create_conversation(pinfo);

    /*
     * Do we already have a state structure for this conv
     */
    classicstun_info = (classicstun_conv_info_t *)conversation_get_proto_data(conversation, proto_classicstun);
    if (!classicstun_info) {
        /* No.  Attach that information to the conversation, and add
         * it to the list of information structures.
         */
        classicstun_info = wmem_new(wmem_file_scope(), classicstun_conv_info_t);
        classicstun_info->pdus=wmem_tree_new(wmem_file_scope());
        conversation_add_proto_data(conversation, proto_classicstun, classicstun_info);
    }

    if(!pinfo->fd->flags.visited){
        if (((msg_type & CLASS_MASK) >> 4) == REQUEST) {
            /* This is a request */
            classicstun_trans=wmem_new(wmem_file_scope(), classicstun_transaction_t);
            classicstun_trans->req_frame=pinfo->fd->num;
            classicstun_trans->rep_frame=0;
            classicstun_trans->req_time=pinfo->fd->abs_ts;
            wmem_tree_insert32_array(classicstun_info->pdus, transaction_id_key,
                           (void *)classicstun_trans);
        } else {
            classicstun_trans=(classicstun_transaction_t *)wmem_tree_lookup32_array(classicstun_info->pdus,
                                 transaction_id_key);
            if(classicstun_trans){
                classicstun_trans->rep_frame=pinfo->fd->num;
            }
        }
    } else {
        classicstun_trans=(classicstun_transaction_t *)wmem_tree_lookup32_array(classicstun_info->pdus, transaction_id_key);
    }
    if(!classicstun_trans){
        /* create a "fake" pana_trans structure */
        classicstun_trans=wmem_new(wmem_packet_scope(), classicstun_transaction_t);
        classicstun_trans->req_frame=0;
        classicstun_trans->rep_frame=0;
        classicstun_trans->req_time=pinfo->fd->abs_ts;
    }



    col_set_str(pinfo->cinfo, COL_PROTOCOL, "CLASSIC-STUN");

    col_add_fstr(pinfo->cinfo, COL_INFO, "Message: %s",
             msg_type_str);

    if (tree) {
        guint transaction_id_first_word;

        ti = proto_tree_add_item(tree, proto_classicstun, tvb, 0, -1, ENC_NA);

        classicstun_tree = proto_item_add_subtree(ti, ett_classicstun);

        if (((msg_type & CLASS_MASK) >> 4) == REQUEST) {
            if (classicstun_trans->rep_frame) {
                proto_item *it;
                it=proto_tree_add_uint(classicstun_tree, hf_classicstun_response_in,
                               tvb, 0, 0,
                               classicstun_trans->rep_frame);
                PROTO_ITEM_SET_GENERATED(it);
            }
        }
        else if ((((msg_type & CLASS_MASK) >> 4) == RESPONSE) ||
             (((msg_type & CLASS_MASK) >> 4) == ERROR_RESPONSE)) {
            /* This is a response */
            if(classicstun_trans->req_frame){
                proto_item *it;
                nstime_t ns;

                it=proto_tree_add_uint(classicstun_tree, hf_classicstun_response_to, tvb, 0, 0, classicstun_trans->req_frame);
                PROTO_ITEM_SET_GENERATED(it);

                nstime_delta(&ns, &pinfo->fd->abs_ts, &classicstun_trans->req_time);
                it=proto_tree_add_time(classicstun_tree, hf_classicstun_time, tvb, 0, 0, &ns);
                PROTO_ITEM_SET_GENERATED(it);
            }

        }

        proto_tree_add_uint(classicstun_tree, hf_classicstun_type, tvb, 0, 2, msg_type);
        proto_tree_add_uint(classicstun_tree, hf_classicstun_length, tvb, 2, 2, msg_length);
        proto_tree_add_item(classicstun_tree, hf_classicstun_id, tvb, 4, 16, ENC_NA);

        /* Remember this (in host order) so we can show clear xor'd addresses */
        transaction_id_first_word = tvb_get_ntohl(tvb, 4);

        if (msg_length > 0) {
            ta = proto_tree_add_item(classicstun_tree, hf_classicstun_att, tvb, CLASSICSTUN_HDR_LEN, msg_length, ENC_NA);
            att_type_tree = proto_item_add_subtree(ta, ett_classicstun_att_type);

            offset = CLASSICSTUN_HDR_LEN;

            while( msg_length > 0) {
                att_type = tvb_get_ntohs(tvb, offset); /* Type field in attribute header */
                att_length = tvb_get_ntohs(tvb, offset+2); /* Length field in attribute header */

                ta = proto_tree_add_text(att_type_tree, tvb, offset,
                             ATTR_HDR_LEN+att_length,
                             "Attribute: %s",
                             val_to_str(att_type, attributes, "Unknown (0x%04x)"));
                att_tree = proto_item_add_subtree(ta, ett_classicstun_att);

                proto_tree_add_uint(att_tree, classicstun_att_type, tvb,
                            offset, 2, att_type);
                offset += 2;
                if (ATTR_HDR_LEN+att_length > msg_length) {
                    proto_tree_add_uint_format_value(att_tree,
                                   classicstun_att_length, tvb, offset, 2,
                                   att_length,
                                   "%u (bogus, goes past the end of the message)",
                                   att_length);
                    break;
                }
                proto_tree_add_uint(att_tree, classicstun_att_length, tvb,
                            offset, 2, att_length);
                offset += 2;
                switch( att_type ){
                    case MAPPED_ADDRESS:
                    case RESPONSE_ADDRESS:
                    case SOURCE_ADDRESS:
                    case CHANGED_ADDRESS:
                    case REFLECTED_FROM:
                    case ALTERNATE_SERVER:
                    case DESTINATION_ADDRESS:
                    case REMOTE_ADDRESS:
                        if (att_length < 2)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_family, tvb, offset+1, 1, ENC_BIG_ENDIAN);
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_port, tvb, offset+2, 2, ENC_BIG_ENDIAN);
                        switch( tvb_get_guint8(tvb, offset+1) ){
                            case 1:
                                if (att_length < 8)
                                    break;
                                proto_tree_add_item(att_tree, classicstun_att_ipv4, tvb, offset+4, 4, ENC_BIG_ENDIAN);
                                break;

                            case 2:
                                if (att_length < 20)
                                    break;
                                proto_tree_add_item(att_tree, classicstun_att_ipv6, tvb, offset+4, 16, ENC_NA);
                                break;
                        }
                        break;

                    case CHANGE_REQUEST:
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_change_ip, tvb, offset, 4, ENC_BIG_ENDIAN);
                        proto_tree_add_item(att_tree, classicstun_att_change_port, tvb, offset, 4, ENC_BIG_ENDIAN);
                        break;

                    case USERNAME:
                    case PASSWORD:
                    case MESSAGE_INTEGRITY:
                    case NONCE:
                    case REALM:
                        if (att_length < 1)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_value, tvb, offset, att_length, ENC_NA);
                        break;

                    case ERROR_CODE:
                        if (att_length < 3)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_error_class, tvb, offset+2, 1, ENC_BIG_ENDIAN);
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_error_number, tvb, offset+3, 1, ENC_BIG_ENDIAN);
                        if (att_length < 5)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_error_reason, tvb, offset+4, (att_length-4), ENC_UTF_8|ENC_NA);
                        break;

                    case LIFETIME:
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_lifetime, tvb, offset, 4, ENC_BIG_ENDIAN);
                        break;

                    case MAGIC_COOKIE:
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_magic_cookie, tvb, offset, 4, ENC_BIG_ENDIAN);
                        break;

                    case BANDWIDTH:
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_bandwidth, tvb, offset, 4, ENC_BIG_ENDIAN);
                        break;

                    case DATA:
                        proto_tree_add_item(att_tree, classicstun_att_data, tvb, offset, att_length, ENC_NA);
                        break;

                    case UNKNOWN_ATTRIBUTES:
                        for (i = 0; i < att_length; i += 4) {
                            proto_tree_add_item(att_tree, classicstun_att_unknown, tvb, offset+i, 2, ENC_BIG_ENDIAN);
                            proto_tree_add_item(att_tree, classicstun_att_unknown, tvb, offset+i+2, 2, ENC_BIG_ENDIAN);
                        }
                        break;

                    case SERVER:
                        proto_tree_add_item(att_tree, classicstun_att_server_string, tvb, offset, att_length, ENC_UTF_8|ENC_NA);
                        break;

                    case XOR_MAPPED_ADDRESS:
                        if (att_length < 2)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_family, tvb, offset+1, 1, ENC_BIG_ENDIAN);
                        if (att_length < 4)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_xor_port, tvb, offset+2, 2, ENC_BIG_ENDIAN);

                        /* Show the port 'in the clear'
                           XOR (host order) transid with (host order) xor-port.
                           Add host-order port into tree. */
                        ti = proto_tree_add_uint(att_tree, classicstun_att_port, tvb, offset+2, 2,
                                     tvb_get_ntohs(tvb, offset+2) ^
                                     (transaction_id_first_word >> 16));
                        PROTO_ITEM_SET_GENERATED(ti);

                        if (att_length < 8)
                            break;
                        switch( tvb_get_guint8(tvb, offset+1) ){
                            case 1:
                                if (att_length < 8)
                                    break;
                                proto_tree_add_item(att_tree, classicstun_att_xor_ipv4, tvb, offset+4, 4, ENC_BIG_ENDIAN);

                                /* Show the address 'in the clear'.
                                   XOR (host order) transid with (host order) xor-address.
                                   Add in network order tree. */
                                ti = proto_tree_add_ipv4(att_tree, classicstun_att_ipv4, tvb, offset+4, 4,
                                             tvb_get_ipv4(tvb, offset+4) ^ g_htonl(transaction_id_first_word));
                                PROTO_ITEM_SET_GENERATED(ti);
                                break;

                            case 2:
                                if (att_length < 20)
                                    break;
                                proto_tree_add_item(att_tree, classicstun_att_xor_ipv6, tvb, offset+4, 16, ENC_NA);
                                break;
                        }
                        break;

                    case REQUESTED_ADDRESS_TYPE:
                        if (att_length < 2)
                            break;
                        proto_tree_add_item(att_tree, classicstun_att_family, tvb, offset+1, 1, ENC_BIG_ENDIAN);
                        break;

                    case CONNECTION_REQUEST_BINDING:
                        proto_tree_add_item(att_tree, classicstun_att_connection_request_binding, tvb, offset, att_length, ENC_UTF_8|ENC_NA);
                        break;

                    default:
                        break;
                }
                offset += att_length;
                msg_length -= ATTR_HDR_LEN+att_length;
            }
        }
    }
    return tvb_captured_length(tvb);
}


static gboolean
dissect_classicstun_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
    if (dissect_classicstun(tvb, pinfo, tree, NULL) == 0)
        return FALSE;

    return TRUE;
}




void
proto_register_classicstun(void)
{
    static hf_register_info hf[] = {
        { &hf_classicstun_type,
            { "Message Type",   "classicstun.type",     FT_UINT16,
            BASE_HEX,   VALS(messages), 0x0,    NULL,   HFILL }
        },
        { &hf_classicstun_length,
            { "Message Length", "classicstun.length",   FT_UINT16,
            BASE_HEX,   NULL,   0x0,    NULL,   HFILL }
        },
        { &hf_classicstun_id,
            { "Message Transaction ID", "classicstun.id",   FT_BYTES,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &hf_classicstun_att,
            { "Attributes",     "classicstun.att",  FT_NONE,
            BASE_NONE,      NULL,   0x0,    NULL,   HFILL }
        },
        { &hf_classicstun_response_in,
            { "Response In", "classicstun.response_in",
            FT_FRAMENUM, BASE_NONE, NULL, 0x0,
            "The response to this CLASSICSTUN query is in this frame", HFILL }},
        { &hf_classicstun_response_to,
            { "Request In", "classicstun.response_to",
            FT_FRAMENUM, BASE_NONE, NULL, 0x0,
            "This is a response to the CLASSICSTUN Request in this frame", HFILL }},
        { &hf_classicstun_time,
            { "Time", "classicstun.time",
            FT_RELATIVE_TIME, BASE_NONE, NULL, 0x0,
            "The time between the Request and the Response", HFILL }},

        /* ////////////////////////////////////// */
        { &classicstun_att_type,
            { "Attribute Type", "classicstun.att.type", FT_UINT16,
            BASE_HEX,   VALS(attributes),   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_length,
            { "Attribute Length",   "classicstun.att.length",   FT_UINT16,
            BASE_DEC,   NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_value,
            { "Value",  "classicstun.att.value",    FT_BYTES,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_family,
            { "Protocol Family",    "classicstun.att.family",   FT_UINT16,
            BASE_HEX,   VALS(attributes_family),    0x0,    NULL,   HFILL }
        },
        { &classicstun_att_ipv4,
            { "IP",     "classicstun.att.ipv4", FT_IPv4,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_ipv6,
            { "IP",     "classicstun.att.ipv6", FT_IPv6,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_port,
            { "Port",   "classicstun.att.port", FT_UINT16,
            BASE_DEC,   NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_change_ip,
            { "Change IP","classicstun.att.change.ip",  FT_BOOLEAN,
            16,     TFS(&tfs_set_notset),   0x0004, NULL,   HFILL}
        },
        { &classicstun_att_change_port,
            { "Change Port","classicstun.att.change.port",  FT_BOOLEAN,
            16,     TFS(&tfs_set_notset),   0x0002, NULL,   HFILL}
        },
        { &classicstun_att_unknown,
            { "Unknown Attribute","classicstun.att.unknown",    FT_UINT16,
            BASE_HEX,   NULL,   0x0,    NULL,   HFILL}
        },
        { &classicstun_att_error_class,
            { "Error Class","classicstun.att.error.class",  FT_UINT8,
            BASE_DEC,   NULL,   0x07,   NULL,   HFILL}
        },
        { &classicstun_att_error_number,
            { "Error Code","classicstun.att.error", FT_UINT8,
            BASE_DEC,   NULL,   0x0,    NULL,   HFILL}
        },
        { &classicstun_att_error_reason,
            { "Error Reason Phase","classicstun.att.error.reason",  FT_STRING,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL}
        },
        { &classicstun_att_xor_ipv4,
            { "IP (XOR-d)",     "classicstun.att.ipv4-xord",    FT_IPv4,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_xor_ipv6,
            { "IP (XOR-d)",     "classicstun.att.ipv6-xord",    FT_IPv6,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_xor_port,
            { "Port (XOR-d)",   "classicstun.att.port-xord",    FT_UINT16,
            BASE_DEC,   NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_server_string,
            { "Server version","classicstun.att.server",    FT_STRING,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL}
        },
        { &classicstun_att_lifetime,
            { "Lifetime",   "classicstun.att.lifetime", FT_UINT32,
            BASE_DEC,   NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_magic_cookie,
            { "Magic Cookie",   "classicstun.att.magic.cookie", FT_UINT32,
            BASE_HEX,   NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_bandwidth,
            { "Bandwidth",  "classicstun.att.bandwidth",    FT_UINT32,
            BASE_DEC,   NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_data,
            { "Data",   "classicstun.att.data", FT_BYTES,
            BASE_NONE,  NULL,   0x0,    NULL,   HFILL }
        },
        { &classicstun_att_connection_request_binding,
            { "Connection Request Binding", "classicstun.att.connection_request_binding", FT_STRING,
            BASE_NONE,  NULL, 0x0,  NULL,   HFILL }
        },
    };

/* Setup protocol subtree array */
    static gint *ett[] = {
        &ett_classicstun,
        &ett_classicstun_att_type,
        &ett_classicstun_att,
    };

/* Register the protocol name and description */
    proto_classicstun = proto_register_protocol("Simple Traversal of UDP Through NAT",
                            "CLASSICSTUN", "classicstun");

/* Required function calls to register the header fields and subtrees used */
    proto_register_field_array(proto_classicstun, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));

    new_register_dissector("classicstun", dissect_classicstun, proto_classicstun);
    new_register_dissector("classicstun-heur", dissect_classicstun_heur, proto_classicstun);
}


void
proto_reg_handoff_classicstun(void)
{
#if 0 /* The stun dissector registers on these ports */
    dissector_handle_t classicstun_handle;

    classicstun_handle = find_dissector("classicstun");

    dissector_add_uint("tcp.port", TCP_PORT_STUN, classicstun_handle);
    dissector_add_uint("udp.port", UDP_PORT_STUN, classicstun_handle);
#endif
    heur_dissector_add("udp", dissect_classicstun_heur, proto_classicstun);
    heur_dissector_add("tcp", dissect_classicstun_heur, proto_classicstun);
}