/* packet-eigrp.c
 * Routines for EIGRP dissection
 * Copyright 2011, Donnie V Savage <dsavage@cisco.com>
 *
 * Complete re-write and replaces previous file of same name authored by:
 *    Copyright 2009, Jochen Bartl <jochen.bartl@gmail.co
 *    Copyright 2000, Paul Ionescu <paul@acorp.ro>
 *
 * 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.
 */
#include "config.h"

#include <glib.h>
#include <epan/packet.h>
#include <epan/guid-utils.h>
#include <epan/addr_resolv.h>
#include <epan/atalk-utils.h>
#include <epan/addr_and_mask.h>
#include <epan/ipproto.h>
#include <epan/tfs.h>
#include <epan/expert.h>
#include <epan/reassemble.h>

#include "packet-ipx.h"
#include "packet-osi.h"

/**
 * EIGRP Header size in bytes
 */
#define EIGRP_HEADER_LENGTH     20

/**
 * EIGRP Packet Opcodes
 */
#define EIGRP_OPC_UPDATE        1       /*!< packet containing routing information */
#define EIGRP_OPC_REQUEST       2       /*!< sent to request one or more routes */
#define EIGRP_OPC_QUERY         3       /*!< sent when a routing is in active start */
#define EIGRP_OPC_REPLY         4       /*!< sent in response to a query */
#define EIGRP_OPC_HELLO         5       /*!< sent to maintain a peering session */
#define EIGRP_OPC_IPXSAP        6       /*!< IPX SAP information */
#define EIGRP_OPC_PROBE         7       /*!< for test purposes   */
#define EIGRP_OPC_ACK           8       /*!< acknowledge         */
#define EIGRP_OPC_STUB          9       /*!< peering operating in restricted mode */
#define EIGRP_OPC_SIAQUERY      10      /*!< QUERY - with relaxed restrictions */
#define EIGRP_OPC_SIAREPLY      11      /*!< REPLY - may contain old routing information */

/**
 * EIGRP TLV Range definitions
 *      PDM             TLV Range
 *      General         0x0000
 *      IPv4            0x0100          ** TLVs for one and all
 *      ATALK           0x0200          ** legacy
 *      IPX             0x0300          ** discontinued
 *      IPv6            0x0400          ** legacy
 *      Multiprotocol   0x0600          ** wide metrics
 *      MultiTopology   0x00f0          ** deprecated
 */
#define EIGRP_TLV_RANGEMASK     0xfff0  /*!< should be 0xff00 - opps     */
#define EIGRP_TLV_GENERAL       0x0000

/**
 * 1.2 TLV Definitions  ** legacy
 * These have been deprecated and should not be used for future packets
 */
#define EIGRP_TLV_IPv4          0x0100          /*!< Classic IPv4 TLV encoding */
#define EIGRP_TLV_ATALK         0x0200          /*!< Classic Appletalk TLV encoding*/
#define EIGRP_TLV_IPX           0x0300          /*!< Classic IPX TLV encoding */
#define EIGRP_TLV_IPv6          0x0400          /*!< Classic IPv6 TLV encoding */

/**
 * 2.0 Multi-Protocol TLV Definitions
 * These have been deprecated and should not be used for future packets
 */
#define EIGRP_TLV_MP            0x0600  /*!< Non-PDM specific encoding */

/**
 * 3.0 TLV Definitions  ** deprecated
 * These have been deprecated and should not be used for future packets
 */
#define EIGRP_TLV_MTR           0x00f0          /*!< MTR TLV encoding */

/**
 * TLV type definitions.  Generic (protocol-independent) TLV types are
 * defined here.  Protocol-specific ones are defined elsewhere.
 */
#define EIGRP_TLV_PARAMETER             (EIGRP_TLV_GENERAL | 0x0001)    /*!< eigrp parameters */
#define EIGRP_TLV_AUTH                  (EIGRP_TLV_GENERAL | 0x0002)    /*!< authentication */
#define EIGRP_TLV_SEQ                   (EIGRP_TLV_GENERAL | 0x0003)    /*!< sequenced packet */
#define EIGRP_TLV_SW_VERSION            (EIGRP_TLV_GENERAL | 0x0004)    /*!< software version */
#define EIGRP_TLV_NEXT_MCAST_SEQ        (EIGRP_TLV_GENERAL | 0x0005)    /*!< */
#define EIGRP_TLV_PEER_STUBINFO         (EIGRP_TLV_GENERAL | 0x0006)    /*!< stub information */
#define EIGRP_TLV_PEER_TERMINATION      (EIGRP_TLV_GENERAL | 0x0007)    /*!< peer termination */
#define EIGRP_TLV_PEER_TIDLIST          (EIGRP_TLV_GENERAL | 0x0008)    /*!< peer sub-topology list */

/**
 * Route Based TLVs
 */
#define EIGRP_TLV_TYPEMASK      0x000f
#define EIGRP_TLV_REQUEST       0x0001
#define EIGRP_TLV_INTERNAL      0x0002
#define EIGRP_TLV_EXTERNAL      0x0003
#define EIGRP_TLV_COMMUNITY     0x0004

/* Legacy TLV formats */
#define EIGRP_TLV_IPv4_REQ      (EIGRP_TLV_IPv4 | EIGRP_TLV_REQUEST)
#define EIGRP_TLV_IPv4_INT      (EIGRP_TLV_IPv4 | EIGRP_TLV_INTERNAL)
#define EIGRP_TLV_IPv4_EXT      (EIGRP_TLV_IPv4 | EIGRP_TLV_EXTERNAL)
#define EIGRP_TLV_IPv4_COM      (EIGRP_TLV_IPv4 | EIGRP_TLV_COMMUNITY)
#define EIGRP_TLV_IPX_INT       (EIGRP_TLV_IPX | EIGRP_TLV_INTERNAL)
#define EIGRP_TLV_IPX_EXT       (EIGRP_TLV_IPX | EIGRP_TLV_EXTERNAL)
#define EIGRP_TLV_IPX_COM       (EIGRP_TLV_IPX | EIGRP_TLV_COMMUNITY)
#define EIGRP_TLV_IPv6_INT      (EIGRP_TLV_IPv6 | EIGRP_TLV_INTERNAL)
#define EIGRP_TLV_IPv6_EXT      (EIGRP_TLV_IPv6 | EIGRP_TLV_EXTERNAL)
#define EIGRP_TLV_IPv6_COM      (EIGRP_TLV_IPv6 | EIGRP_TLV_COMMUNITY)

/* Deprecated TLV formats */
#define EIGRP_TLV_AT_INT        (EIGRP_TLV_ATALK | EIGRP_TLV_INTERNAL)
#define EIGRP_TLV_AT_EXT        (EIGRP_TLV_ATALK | EIGRP_TLV_EXTERNAL)
#define EIGRP_TLV_AT_CBL        (EIGRP_TLV_ATALK | 0x04)
#define EIGRP_TLV_MTR_REQ       (EIGRP_TLV_MTR | EIGRP_TLV_REQUEST)
#define EIGRP_TLV_MTR_INT       (EIGRP_TLV_MTR | EIGRP_TLV_INTERNAL)
#define EIGRP_TLV_MTR_EXT       (EIGRP_TLV_MTR | EIGRP_TLV_EXTERNAL)
#define EIGRP_TLV_MTR_COM       (EIGRP_TLV_MTR | EIGRP_TLV_COMMUNITY)
#define EIGRP_TLV_MTR_TIDLIST   (EIGRP_TLV_MTR | 0x0005)

/* Current "Wide Metric" TLV formats */
#define EIGRP_TLV_MP_REQ        (EIGRP_TLV_MP | EIGRP_TLV_REQUEST)
#define EIGRP_TLV_MP_INT        (EIGRP_TLV_MP | EIGRP_TLV_INTERNAL)
#define EIGRP_TLV_MP_EXT        (EIGRP_TLV_MP | EIGRP_TLV_EXTERNAL)
#define EIGRP_TLV_MP_COM        (EIGRP_TLV_MP | EIGRP_TLV_COMMUNITY)

/**
 * External routes originate from some other protocol - these are them
 */
#define NULL_PROTID     0       /*!< unknown protocol */
#define IGRP1_PROTID    1       /*!< IGRP.. whos your daddy! */
#define IGRP2_PROTID    2       /*!< EIGRP - Just flat out the best */
#define STATIC_PROTID   3       /*!< Staticly configured source */
#define RIP_PROTID      4       /*!< Routing Information Protocol */
#define HELLO_PROTID    5       /*!< Hello? RFC-891 you there? */
#define OSPF_PROTID     6       /*!< OSPF - Open Shortest Path First */
#define ISIS_PROTID     7       /*!< Intermediate System To Intermediate System */
#define EGP_PROTID      8       /*!< Exterior Gateway Protocol */
#define BGP_PROTID      9       /*!< Border Gateway Protocol */
#define IDRP_PROTID     10      /*!< InterDomain Routing Protocol */
#define CONN_PROTID     11      /*!< Connected source */

/**
 *
 * extdata flag field definitions
 */
#define EIGRP_OPAQUE_EXT      0x01   /*!< Route is external */
#define EIGRP_OPAQUE_CD       0x02   /*!< Candidate default route */

/**
 * Address-Family types are taken from:
 *       http://www.iana.org/assignments/address-family-numbers
 * to provide a standards based exchange of AFI information between
 * EIGRP routers.
 */
#define EIGRP_AF_IPv4           1       /*!< IPv4 (IP version 4) */
#define EIGRP_AF_IPv6           2       /*!< IPv6 (IP version 6) */
#define EIGRP_AF_IPX            11      /*!< IPX */
#define EIGRP_AF_ATALK          12      /*!< Appletalk */
#define EIGRP_SF_COMMON         16384   /*!< Cisco Service Family */
#define EIGRP_SF_IPv4           16385   /*!< Cisco IPv4 Service Family */
#define EIGRP_SF_IPv6           16386   /*!< Cisco IPv6 Service Family */

/**
 * Authentication types supported by EIGRP
 */
#define EIGRP_AUTH_TYPE_NONE            0
#define EIGRP_AUTH_TYPE_TEXT            1
#define EIGRP_AUTH_TYPE_MD5             2
#define EIGRP_AUTH_TYPE_MD5_LEN         16
#define EIGRP_AUTH_TYPE_SHA256          3
#define EIGRP_AUTH_TYPE_SHA256_LEN      32

/**
 * opaque flag field definitions
 */
#define EIGRP_OPAQUE_SRCWD    0x01   /*!< Route Source Withdraw */
#define EIGRP_OPAQUE_ACTIVE   0x04   /*!< Route is currently in active state */
#define EIGRP_OPAQUE_REPL     0x08   /*!< Route is replicated from different tableid */

/**
 * pak flag bit field definitions - 0 (none)-7 source priority
 */
#define EIGRP_PRIV_DEFAULT      0x00   /* 0 (none)-7 source priority */
#define EIGRP_PRIV_LOW          0x01
#define EIGRP_PRIV_MEDIUM       0x04
#define EIGRP_PRIV_HIGH         0x07

/**
 * stub bit definitions
 */
#define EIGRP_PEER_ALLOWS_CONNECTED     0x0001
#define EIGRP_PEER_ALLOWS_STATIC        0x0002
#define EIGRP_PEER_ALLOWS_SUMMARY       0x0004
#define EIGRP_PEER_ALLOWS_REDIST        0x0008
#define EIGRP_PEER_ALLOWS_LEAKING       0x0010
#define EIGRP_PEER_ALLOWS_RCVONLY       0x0020

/*
 * Init bit definition. First unicast transmitted Update has this
 * bit set in the flags field of the fixed header. It tells the neighbor
 * to down-load his topology table.
 */
#define EIGRP_INIT_FLAG 0x01

/*
 * CR bit (Conditionally Received) definition in flags field on header. Any
 * packets with the CR-bit set can be accepted by an EIGRP speaker if and
 * only if a previous Hello was received with the SEQUENCE_TYPE TLV present.
 *
 * This allows multicasts to be transmitted in order and reliably at the
 * same time as unicasts are transmitted.
 */
#define EIGRP_CR_FLAG 0x02

/*
 * RS bit.  The Restart flag is set in the hello and the init
 * update packets during the nsf signaling period.  A nsf-aware
 * router looks at the RS flag to detect if a peer is restarting
 * and maintain the adjacency. A restarting router looks at
 * this flag to determine if the peer is helping out with the restart.
 */
#define EIGRP_RS_FLAG 0x04

/*
 * EOT bit.  The End-of-Table flag marks the end of the start-up updates
 * sent to a new peer.  A nsf restarting router looks at this flag to
 * determine if it has finished receiving the start-up updates from all
 * peers.  A nsf-aware router waits for this flag before cleaning up
 * the stale routes from the restarting peer.
 */
#define EIGRP_EOT_FLAG 0x08

/**
 * EIGRP Virtual Router ID
 *
 * Define values to deal with EIGRP virtual router ids.  Virtual
 * router IDs are stored in the upper short of the EIGRP fixed packet
 * header.  The lower short of the packet header continues to be used
 * as asystem number.
 *
 * Virtual Router IDs are PDM-independent.  All PDMs will use
 * VRID_BASE to indicate the 'base' or 'legacy' EIGRP instance.
 * All PDMs need to initialize their vrid to VRID_BASE for compatibility
 * with legacy routers.
 * Once IPv6 supports 'MTR Multicast', it will use the same VRID as
 * IPv4.  No current plans to support VRIDs on IPX. :)
 * Initial usage of VRID is to signal usage of Multicast topology for
 * MTR.
 *
 * VRID_MCAST is a well known constant, other VRIDs will be determined
 * programmatic...
 *
 * With the addition of SAF the VRID space has been divided into two
 * segments 0x0000-0x7fff is for EIGRP and vNets, 0x8000-0xffff is
 * for saf and its associated vNets.
 */
#define EIGRP_VRID_MASK         0x8001
#define EIGRP_VRID_AF_BASE      0x0000
#define EIGRP_VRID_MCAST_BASE   0x0001
#define EIGRP_VRID_SF_BASE      0x8000

/* Extended Attributes for a destination */
#define EIGRP_ATTR_HDRLEN (2)
#define EIGRP_ATTR_MAXDATA (512)

#define EIGRP_ATTR_NOOP         0       /*!< No-Op used as offset padding */
#define EIGRP_ATTR_SCALED       1       /*!< Scaled metric values */
#define EIGRP_ATTR_TAG          2       /*!< Tag assigned by Admin for dest */
#define EIGRP_ATTR_COMM         3       /*!< Community attribute for dest */
#define EIGRP_ATTR_JITTER       4       /*!< Variation in path delay */
#define EIGRP_ATTR_QENERGY      5       /*!< Non-Active energy usage along path */
#define EIGRP_ATTR_ENERGY       6       /*!< Active energy usage along path */

/*
 * Begin EIGRP-BGP interoperability communities
 */
#define EIGRP_EXTCOMM_SOO_ASFMT         0x0003 /* Site-of-Origin, BGP AS format */
#define EIGRP_EXTCOMM_SOO_ADRFMT        0x0103 /* Site-of-Origin, BGP/EIGRP addr format */

/*
 * EIGRP Specific communities
 */
#define EIGRP_EXTCOMM_EIGRP             0x8800 /* EIGRP route information appended*/
#define EIGRP_EXTCOMM_DAD               0x8801 /* EIGRP AS + Delay           */
#define EIGRP_EXTCOMM_VRHB              0x8802 /* EIGRP Vector: Reliability + Hop + BW */
#define EIGRP_EXTCOMM_SRLM              0x8803 /* EIGRP System: Reserve +Load + MTU   */
#define EIGRP_EXTCOMM_SAR               0x8804 /* EIGRP System: Remote AS + Remote ID  */
#define EIGRP_EXTCOMM_RPM               0x8805 /* EIGRP Remote: Protocol + Metric    */
#define EIGRP_EXTCOMM_VRR               0x8806 /* EIGRP Vecmet: Rsvd + (internal) Routerid */

/* SAF types */
#define EIGRP_SVCDATA_COMPLETE          0x01    /*!< Data is attached */
#define EIGRP_SVCDATA_TRIMMED           0x02    /*!< Data was trimmed from service */

/* SAF Defined Numbers */
#define SAF_SERVICE_ID_CAPMAN   100             /*!< Capabilities Manager */
#define SAF_SERVICE_ID_UC       101             /*!< Unified Communications */
#define SAF_SERVICE_ID_PFR      102             /*!< Performance Routing */

/* Forward declaration we need below (if using proto_reg_handoff...
   as a prefs callback)       */
void proto_reg_handoff_eigrp(void);
void proto_register_eigrp(void);

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

/* header */
static gint hf_eigrp_version = -1;
static gint hf_eigrp_opcode = -1;
static gint hf_eigrp_flags = -1;
static gint hf_eigrp_sequence = -1;
static gint hf_eigrp_acknowledge = -1;
static gint hf_eigrp_vrid = -1;
static gint hf_eigrp_as = -1;
static gint ett_eigrp = -1;

/* packet header flags */
static gint hf_eigrp_flags_init = -1;
static gint hf_eigrp_flags_restart = -1;
static gint hf_eigrp_flags_eot = -1;
static gint hf_eigrp_flags_condrecv = -1;

static gint ett_eigrp_flags = -1;
static const int *eigrp_flag_fields[] = {
    &hf_eigrp_flags_init,
    &hf_eigrp_flags_condrecv,
    &hf_eigrp_flags_restart,
    &hf_eigrp_flags_eot,
    NULL
};

/* tlv */
static gint hf_eigrp_tlv_type = -1;
static gint hf_eigrp_tlv_len = -1;
static gint hf_eigrp_tid = -1;
static gint hf_eigrp_afi = -1;
static gint hf_eigrp_nullpad = -1;

static gint ett_eigrp_tlv = -1;
static gint ett_eigrp_tlv_metric = -1;
static gint ett_eigrp_tlv_attr = -1;
static gint ett_eigrp_tlv_extdata = -1;

/* param */
static gint hf_eigrp_par_k1 = -1;
static gint hf_eigrp_par_k2 = -1;
static gint hf_eigrp_par_k3 = -1;
static gint hf_eigrp_par_k4 = -1;
static gint hf_eigrp_par_k5 = -1;
static gint hf_eigrp_par_k6 = -1;
static gint hf_eigrp_par_holdtime = -1;

/* auth */
static gint hf_eigrp_auth_type = -1;
static gint hf_eigrp_auth_len = -1;
static gint hf_eigrp_auth_keyid = -1;
static gint hf_eigrp_auth_keyseq = -1;
static gint hf_eigrp_auth_digest = -1;

/* seq */
static gint hf_eigrp_seq_addrlen = -1;
static gint hf_eigrp_seq_ipv4addr = -1;
static gint hf_eigrp_seq_ipv6addr = -1;

/* multicast seq */
static gint hf_eigrp_next_mcast_seq = -1;

/* stub flags */
static gint hf_eigrp_stub_flags = -1;
static gint hf_eigrp_stub_flags_connected = -1;
static gint hf_eigrp_stub_flags_static = -1;
static gint hf_eigrp_stub_flags_summary = -1;
static gint hf_eigrp_stub_flags_recvonly = -1;
static gint hf_eigrp_stub_flags_redist = -1;
static gint hf_eigrp_stub_flags_leakmap = -1;

static gint ett_eigrp_stub_flags = -1;
static const int *eigrp_stub_flag_fields[] = {
    &hf_eigrp_stub_flags_connected,
    &hf_eigrp_stub_flags_static,
    &hf_eigrp_stub_flags_summary,
    &hf_eigrp_stub_flags_redist,
    &hf_eigrp_stub_flags_leakmap,
    &hf_eigrp_stub_flags_recvonly,
    NULL
};

/* tid */
static gint hf_eigrp_tidlist_tid = -1;
static gint hf_eigrp_tidlist_flags = -1;
static gint hf_eigrp_tidlist_len = -1;
static gint ett_eigrp_tidlist = -1;

/* 1.2 and 3.0 metric */
static gint hf_eigrp_legacy_metric_delay = -1;
static gint hf_eigrp_legacy_metric_bw = -1;
static gint hf_eigrp_legacy_metric_mtu = -1;
static gint hf_eigrp_legacy_metric_hopcount = -1;
static gint hf_eigrp_legacy_metric_rel = -1;
static gint hf_eigrp_legacy_metric_load = -1;
static gint hf_eigrp_legacy_metric_intag = -1;

/* 3.0 metric */
static gint hf_eigrp_legacy_metric_tag = -1;

/* 2.0 metric */
static gint hf_eigrp_metric_offset = -1;
static gint hf_eigrp_metric_priority = -1;
static gint hf_eigrp_metric_rel = -1;
static gint hf_eigrp_metric_load = -1;
static gint hf_eigrp_metric_mtu = -1;
static gint hf_eigrp_metric_hopcount = -1;
static gint hf_eigrp_metric_reserved = -1;

/* router id*/
static gint hf_eigrp_routerid = -1;

/* protocol dependent module route flags */
static gint hf_eigrp_metric_flags_srcwd = -1;
static gint hf_eigrp_metric_flags_active = -1;
static gint hf_eigrp_metric_flags_repl = -1;
static gint ett_eigrp_metric_flags = -1;

/* extended metrics */
static gint hf_eigrp_attr_opcode = -1;
static gint hf_eigrp_attr_offset = -1;
static gint hf_eigrp_attr_scaled = -1;
static gint hf_eigrp_attr_tag = -1;
static gint hf_eigrp_attr_jitter = -1;
static gint hf_eigrp_attr_qenergy = -1;
static gint hf_eigrp_attr_energy = -1;

/* route external data */
static gint hf_eigrp_extdata_origrid = -1;
static gint hf_eigrp_extdata_as = -1;
static gint hf_eigrp_extdata_tag = -1;
static gint hf_eigrp_extdata_metric = -1;
static gint hf_eigrp_extdata_reserved = -1;
static gint hf_eigrp_extdata_proto = -1;

static gint hf_eigrp_extdata_flag_ext = -1;
static gint hf_eigrp_extdata_flag_cd = -1;
static gint ett_eigrp_extdata_flags = -1;

/* ipv4 address */
static gint hf_eigrp_ipv4_nexthop = -1;
static gint hf_eigrp_ipv4_prefixlen = -1;

/* ipv6 address */
static gint hf_eigrp_ipv6_nexthop = -1;
static gint hf_eigrp_ipv6_prefixlen = -1;

/* ipx address */
static gint hf_eigrp_ipx_nexthop_net = -1;
static gint hf_eigrp_ipx_nexthop_host = -1;
static gint hf_eigrp_ipx_extdata_routerid = -1;
static gint hf_eigrp_ipx_extdata_delay = -1;
static gint hf_eigrp_ipx_extdata_metric = -1;
static gint hf_eigrp_ipx_dest = -1;

/* appletalk address */
static gint hf_eigrp_atalk_routerid = -1;

/* SAF services */
static gint hf_eigrp_saf_service = -1;
static gint hf_eigrp_saf_subservice = -1;
static gint hf_eigrp_saf_guid = -1;

static gint hf_eigrp_saf_reachability_afi = -1;
static gint hf_eigrp_saf_reachability_port = -1;
static gint hf_eigrp_saf_reachability_protocol = -1;
static gint hf_eigrp_saf_reachability_addr_ipv4 = -1;
static gint hf_eigrp_saf_reachability_addr_ipv6 = -1;
static gint hf_eigrp_saf_reachability_addr_hex = -1;
static gint ett_eigrp_saf_reachability = -1;

static gint hf_eigrp_saf_data_length = -1;
static gint hf_eigrp_saf_data_sequence = -1;
static gint hf_eigrp_saf_data_type = -1;

static expert_field ei_eigrp_checksum_bad = EI_INIT;
static expert_field ei_eigrp_unreachable = EI_INIT;
static expert_field ei_eigrp_seq_addrlen = EI_INIT;
static expert_field ei_eigrp_peer_termination = EI_INIT;
static expert_field ei_eigrp_tlv_type = EI_INIT;
static expert_field ei_eigrp_auth_type = EI_INIT;
static expert_field ei_eigrp_peer_termination_graceful = EI_INIT;
static expert_field ei_eigrp_auth_len = EI_INIT;
static expert_field ei_eigrp_tlv_len = EI_INIT;
static expert_field ei_eigrp_afi = EI_INIT;
static expert_field ei_eigrp_prefixlen = EI_INIT;
static expert_field ei_eigrp_tlv_trunc = EI_INIT;

/* some extra handle that might be needed */
static dissector_handle_t ipxsap_handle = NULL;
static dissector_table_t media_type_table = NULL;

static const value_string eigrp_opcode2string[] = {
    { EIGRP_OPC_UPDATE,         "Update" },
    { EIGRP_OPC_REQUEST,        "Request" },
    { EIGRP_OPC_QUERY,          "Query" },
    { EIGRP_OPC_REPLY,          "Reply" },
    { EIGRP_OPC_HELLO,          "Hello" },
    { EIGRP_OPC_IPXSAP,         "IPX/SAP Update" },
    { EIGRP_OPC_PROBE,          "Route Probe" },
    { EIGRP_OPC_ACK,            "Hello (Ack)" },
    { EIGRP_OPC_STUB,           "Stub-Info" },
    { EIGRP_OPC_SIAQUERY,       "SIA-Query" },
    { EIGRP_OPC_SIAREPLY,       "SIA-Reply" },
    { 0, NULL }
};

static const value_string eigrp_tlv2string[] = {
    /* General TLV formats */
    { EIGRP_TLV_PARAMETER,              "Parameters"},
    { EIGRP_TLV_AUTH,                   "Authentication"},
    { EIGRP_TLV_SEQ,                    "Sequence"},
    { EIGRP_TLV_SW_VERSION,             "Software Version"},
    { EIGRP_TLV_NEXT_MCAST_SEQ,         "Next multicast sequence"},
    { EIGRP_TLV_PEER_STUBINFO,          "Peer Stub Information"},
    { EIGRP_TLV_PEER_TERMINATION,       "Peer Termination"},
    { EIGRP_TLV_PEER_TIDLIST,           "Peer Topology ID List"},

    /* Legacy TLV formats */
    { EIGRP_TLV_IPv4_INT,               "Internal Route(IPv4)"},
    { EIGRP_TLV_IPv4_EXT,               "External Route(IPv4)"},
    { EIGRP_TLV_IPv4_COM,               "Ext-Community(IPv4)"},
    { EIGRP_TLV_IPv6_INT,               "Internal Route(IPv6)"},
    { EIGRP_TLV_IPv6_EXT,               "External Route(IPv6)"},
    { EIGRP_TLV_IPv6_COM,               "Ext-Community(IPv6)"},
    { EIGRP_TLV_IPX_INT,                "IPX Internal Route(IPX)"},
    { EIGRP_TLV_IPX_EXT,                "IPX External Route(IPX)"},

    /* Deprecated TLV formats */
    { EIGRP_TLV_AT_INT,                 "Internal Route(ATALK)"},
    { EIGRP_TLV_AT_EXT,                 "External Route(ATALK)"},
    { EIGRP_TLV_AT_CBL,                 "Cable Configuration(ATALK)"},
    { EIGRP_TLV_MTR_REQ,                "Request(MTR)"},
    { EIGRP_TLV_MTR_INT,                "Internal Route(MTR)"},
    { EIGRP_TLV_MTR_EXT,                "External Route(MTR)"},
    { EIGRP_TLV_MTR_COM,                "Ext-Community(MTR)"},
    { EIGRP_TLV_MTR_TIDLIST,            "TopologyID List"},

    /* Current "Wide Metric" TLV formats */
    { EIGRP_TLV_MP_REQ,                 "Request"},
    { EIGRP_TLV_MP_INT,                 "Internal Route"},
    { EIGRP_TLV_MP_EXT,                 "External Route"},
    { EIGRP_TLV_MP_COM,                 "Ext-Community"},

    { 0, NULL}
};

static const value_string eigrp_proto2string[] = {
    { IGRP1_PROTID,             "IGRP"},
    { IGRP2_PROTID,             "EIGRP"},
    { STATIC_PROTID,            "Static Route"},
    { RIP_PROTID,               "RIP"},
    { HELLO_PROTID,             "Hello"},
    { OSPF_PROTID,              "OSPF"},
    { ISIS_PROTID,              "IS-IS"},
    { EGP_PROTID,               "EGP"},
    { BGP_PROTID,               "BGP"},
    { IDRP_PROTID,              "IDRP"},
    { CONN_PROTID,              "Connected Route"},
    { 0, NULL}
};

static const value_string eigrp_auth2string[] = {
    { EIGRP_AUTH_TYPE_TEXT,     "TEXT"},
    { EIGRP_AUTH_TYPE_MD5,      "MD5"},
    { EIGRP_AUTH_TYPE_SHA256,   "SHA256"},
    { 0, NULL},
};

static const value_string eigrp_vrid2string[] = {
    { EIGRP_VRID_AF_BASE,       "(Address-Family)"},
    { EIGRP_VRID_SF_BASE,       "(Service-Family)"},
    { EIGRP_VRID_MCAST_BASE,    "(Multi-Cast)"},
    { 0, NULL}
};

static const value_string eigrp_afi2string[] = {
    { EIGRP_AF_IPv4,            "IPv4"},
    { EIGRP_AF_IPv6,            "IPv6"},
    { EIGRP_AF_IPX,             "IPX"},
    { EIGRP_AF_ATALK,           "Appletalk"},
    { EIGRP_SF_COMMON,          "Service Family"},
    { EIGRP_SF_IPv4,            "IPv4 Service Family"},
    { EIGRP_SF_IPv6,            "IPv6 Service Family"},
    { 0, NULL}
};

static const value_string eigrp_attr_opcode2string[] = {
    { EIGRP_ATTR_NOOP,          "NO-OP for padding"},
    { EIGRP_ATTR_SCALED,        "Scaled Metric"},
    { EIGRP_ATTR_TAG,           "Admin Tag"},
    { EIGRP_ATTR_COMM,          "Community"},
    { EIGRP_ATTR_JITTER,        "Jitter"},
    { EIGRP_ATTR_QENERGY,       "Non-Active energy"},
    { EIGRP_ATTR_ENERGY,        "Active energy"},
    { 0, NULL}
};

static const value_string eigrp_saf_type2string[] = {
    { EIGRP_SVCDATA_COMPLETE,   "Attached Service Data"},
    { EIGRP_SVCDATA_TRIMMED,    "Trimmed Service Data"},
    { 0, NULL}
};

static const value_string eigrp_saf_srv2string[] = {
    { SAF_SERVICE_ID_CAPMAN,    "Capabilities Manager"},
    { SAF_SERVICE_ID_UC,        "Unified Communications"},
    { SAF_SERVICE_ID_PFR,       "Performance Routing"},
    { 0, NULL}
};

/**
 *@fn void dissect_eigrp_parameter (proto_tree *tree, tvbuff_t *tvb, packet_info *pinfo,
 *
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 *
 * @par
 * Dissect the Parameter TLV, which is used to convey metric weights and the
 * hold time.
 *
 * @usage
 * Note the addition of K6 for the new extended metrics, and does not apply to
 * older TLV packet formats.
 */
static void
dissect_eigrp_parameter (proto_tree *tree, tvbuff_t *tvb, packet_info *pinfo,
                         proto_item *ti)
{
    int    offset = 0;
    guint8 k1, k2, k3, k4, k5;

    k1 = tvb_get_guint8(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_par_k1, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;
    k2 = tvb_get_guint8(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_par_k2, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;
    k3 = tvb_get_guint8(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_par_k3, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;
    k4 = tvb_get_guint8(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_par_k4, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;
    k5 = tvb_get_guint8(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_par_k5, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;
    proto_tree_add_item(tree, hf_eigrp_par_k6, tvb, offset, 1, ENC_BIG_ENDIAN);

    offset += 1;
    proto_tree_add_item(tree, hf_eigrp_par_holdtime, tvb, offset, 2, ENC_BIG_ENDIAN);

    if (k1 == 255 && k2 == 255 && k3 == 255 && k4 == 255 && k5 == 255) {
        proto_item_append_text(ti, ": Peer Termination");
        expert_add_info(pinfo, ti, &ei_eigrp_peer_termination);
    }
}

/**
 *@fn void dissect_eigrp_auth_tlv (proto_tree *tree, tvbuff_t *tvb,
 *                                 packet_info *pinfo, proto_item *ti)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 *
 * @par
 * Dissect the Authentication TLV and display digest. Currently MD5 and SHA256
 * HMAC is supported.  For SHA256, a "secret key" with the HMAC-SHA-256
 * password, the source address from which the packet is sent. This combined
 * string is used as the key for hash calculation.
 */
static void
dissect_eigrp_auth_tlv (proto_tree *tree, tvbuff_t *tvb,
                        packet_info *pinfo, proto_item *ti)
{
    proto_item *ti_auth_type, *ti_auth_len;
    int         offset = 0;
    guint16     auth_type, auth_len;

    /* print out what family we dealing with... */

    auth_type = tvb_get_ntohs(tvb, 0);
    auth_len = tvb_get_ntohs(tvb, 2);

    proto_item_append_text(ti, " %s", val_to_str_const(auth_type, eigrp_auth2string, ""));

    ti_auth_type = proto_tree_add_item(tree, hf_eigrp_auth_type, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;
    ti_auth_len = proto_tree_add_item(tree, hf_eigrp_auth_len, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;
    proto_tree_add_item(tree, hf_eigrp_auth_keyid, tvb, offset, 4, ENC_BIG_ENDIAN);
    offset += 4;
    proto_tree_add_item(tree, hf_eigrp_auth_keyseq, tvb, offset, 4, ENC_BIG_ENDIAN);
    offset += 4;
    proto_tree_add_item(tree, hf_eigrp_nullpad, tvb, offset, 8, ENC_NA);
    offset += 8;

    switch (auth_type) {
    case EIGRP_AUTH_TYPE_MD5:
        if (EIGRP_AUTH_TYPE_MD5_LEN != auth_len) {
            expert_add_info_format(pinfo, ti_auth_len, &ei_eigrp_auth_len, "Invalid auth len %u", auth_len);
        } else {
            proto_tree_add_item(tree, hf_eigrp_auth_digest, tvb, offset,
                                EIGRP_AUTH_TYPE_MD5_LEN, ENC_NA);
        }
        break;

    case EIGRP_AUTH_TYPE_SHA256:
        if (EIGRP_AUTH_TYPE_SHA256_LEN != auth_len) {
            expert_add_info_format(pinfo, ti_auth_len, &ei_eigrp_auth_len, "Invalid auth len %u", auth_len);

        } else {
            proto_tree_add_item(tree, hf_eigrp_auth_digest, tvb, offset,
                                EIGRP_AUTH_TYPE_SHA256_LEN, ENC_NA);
        }
        break;

    case EIGRP_AUTH_TYPE_NONE:
    case EIGRP_AUTH_TYPE_TEXT:
    default:
        expert_add_info_format(pinfo, ti_auth_type, &ei_eigrp_auth_type, "Invalid auth type %u", auth_type);
        break;
    }
}

/**
 *@fn void dissect_eigrp_seq_tlv (proto_tree *tree, tvbuff_t *tvb,
 *                                packet_info *pinfo, proto_item *ti)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 *
 * @par
 * Dissect the Sequence TLV which consists of the addresses of peers that must
 * not receive the next multicast packet transmitted.
 */
static void
dissect_eigrp_seq_tlv (proto_tree *tree, tvbuff_t *tvb,
                       packet_info *pinfo, proto_item *ti)
{
    proto_item *ti_addrlen;
    int         offset = 0;
    guint8      addr_len;

    while (tvb_reported_length_remaining(tvb, offset) > 0) {
        addr_len = tvb_get_guint8(tvb, offset);
        ti_addrlen = proto_tree_add_item(tree, hf_eigrp_seq_addrlen, tvb, offset, 1, ENC_BIG_ENDIAN);
        offset += 1;

        if (tvb_reported_length_remaining(tvb, offset) < addr_len) {
            /* The remaining part of the TLV is shorter than the address it should contain */
            expert_add_info(pinfo, ti, &ei_eigrp_tlv_trunc);
            break;
        }

        switch (addr_len) {
        case 4:
            /* IPv4 */
            proto_tree_add_item(tree, hf_eigrp_seq_ipv4addr, tvb, offset, addr_len, ENC_BIG_ENDIAN);
            break;
        case 10:
            /* IPX */
            proto_tree_add_text(tree, tvb, offset, addr_len,
                                "IPX Address = %08x.%04x.%04x.%04x",
                                tvb_get_ntohl(tvb, 1), tvb_get_ntohs(tvb, 5),
                                tvb_get_ntohs(tvb, 7), tvb_get_ntohs(tvb, 9));
            break;
        case 16:
            /* IPv6 */
            proto_tree_add_item(tree, hf_eigrp_seq_ipv6addr, tvb, offset, addr_len,
                                ENC_NA);
            break;
        default:
            expert_add_info(pinfo, ti_addrlen, &ei_eigrp_seq_addrlen);
        }

        offset += addr_len;
    }
}

/**
 *@fn void dissect_eigrp_sw_version (tvbuff_t *tvb, proto_tree *tree,
 *                                   proto_item *ti)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] ti        protocol item
 *
 * @par
 * Dissect Software Version TLV.  The older versions of EIGRP sent the IOS
 * version along with the TLV Version.   When EIGRP "plugins" were created,
 * this as change to send the "Release" of EIGRP to better identify where fixes
 * are present(missing)
 */
static void
dissect_eigrp_sw_version (tvbuff_t *tvb, proto_tree *tree,
                          proto_item *ti)
{
    int    offset = 0;
    guint8 ios_rel_major, ios_rel_minor;
    guint8 eigrp_rel_major, eigrp_rel_minor;

    ios_rel_major = tvb_get_guint8(tvb, 0);
    ios_rel_minor = tvb_get_guint8(tvb, 1);
    proto_tree_add_text(tree, tvb, offset, 2, "EIGRP Release: %u.%u",
                        ios_rel_major, ios_rel_minor);
    offset += 2;
    proto_item_append_text(ti, ": EIGRP=%u.%u", ios_rel_major, ios_rel_minor);

    eigrp_rel_major = tvb_get_guint8(tvb, 2);
    eigrp_rel_minor = tvb_get_guint8(tvb, 3);
    proto_tree_add_text(tree,tvb,offset, 2, "EIGRP TLV version: %u.%u",
                        eigrp_rel_major, eigrp_rel_minor);
    proto_item_append_text(ti, ", TLV=%u.%u",
                           eigrp_rel_major, eigrp_rel_minor);
}

/**
 *@fn void dissect_eigrp_next_mcast_seq (tvbuff_t *tvb, proto_tree *tree,
 *                                      proto_item *ti)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] ti        protocol item
 *
 * @par
 * Dissect Next Multicast Sequence TLV, which is part of the Hello with a
 * Sequence TLV;  this gives a two-way binding between the packets and plugs a
 * hole where a multicast could be received  by the wrong peers (due to a
 * string of lost packets).
 */
static void
dissect_eigrp_next_mcast_seq (tvbuff_t *tvb, proto_tree *tree,
                              proto_item *ti)
{
    proto_tree_add_item(tree, hf_eigrp_next_mcast_seq, tvb, 0, 4,
                        ENC_BIG_ENDIAN);
    proto_item_append_text(ti, ": %u", tvb_get_ntohl(tvb, 0));
}

/**
 *@fn void dissect_eigrp_peer_stubinfo (tvbuff_t *tvb, proto_tree *tree)
 *
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 *
 * @par
 * Dissect the PEER STUB TLV which contains the route types which the Peer will
 * advertise. This is used to suppress QUERYs from being sent to the Peer
 */
static void
dissect_eigrp_peer_stubinfo (tvbuff_t *tvb, proto_tree *tree)
{
    proto_tree_add_bitmask(tree, tvb, 0, hf_eigrp_stub_flags, ett_eigrp_stub_flags,
                           eigrp_stub_flag_fields, ENC_BIG_ENDIAN);
}

/**
 *@fn void dissect_eigrp_peer_termination (packet_info *pinfo, proto_item *ti)
 *
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 *
 * @par
 * Dissect Peer Termination TLV.  This TLV has no parameters and is used to
 * signal an adjacency should be tore down
 */
static void
dissect_eigrp_peer_termination (packet_info *pinfo, proto_item *ti)
{
    expert_add_info(pinfo, ti, &ei_eigrp_peer_termination_graceful);
}

/**
 *@fn void dissect_eigrp_peer_tidlist (proto_tree *tree, tvbuff_t *tvb)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 *
 * @par
 *  Dissect the Topology Identifier List TLV.  This TLV was introduced as part
 *  of the "MTR (Multi-Topology Routing) Project to support sub topologies
 *  within a given Autonomous System. The following represents the format of
 *  the TID list
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |            Flags             |         Length                 |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |        Variable Length TID (two bytes) list                   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
static void
dissect_eigrp_peer_tidlist (proto_tree *tree, tvbuff_t *tvb)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    int         offset = 0;
    guint16     size;

    proto_tree_add_item(tree, hf_eigrp_tidlist_flags, tvb, offset, 2,
                        ENC_BIG_ENDIAN);
    offset += 2;

    size = tvb_get_ntohs(tvb, offset) / 2;
    proto_tree_add_item(tree, hf_eigrp_tidlist_len, tvb, offset, 2,
                        ENC_BIG_ENDIAN);
    offset += 2;

    sub_ti = proto_tree_add_text(tree, tvb, offset, (size*2), "%d TIDs", size);
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_tidlist);
    for (; size ; size--) {
        proto_tree_add_item(sub_tree, hf_eigrp_tidlist_tid, tvb, offset, 2,
                            ENC_BIG_ENDIAN);
        offset += 2;
    }
}

/**
 *@fn int dissect_eigrp_extdata_flags (proto_tree *tree, tvbuff_t *tvb, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the Flags field in the external data section of an external
 * route.The following represents the format of the bit field
 *
 *    7 6 5 4 3 2 1 0
 *   +-+-+-+-+-+-+-+-+
 *   |   Flags       |
 *   +-+-+-+-+-+-+-+-+
 *                | |
 *                | +- Route is External *not used*
 *                +--- Route is Candidate Default
 */
static int
dissect_eigrp_extdata_flags (proto_tree *tree, tvbuff_t *tvb, int offset)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;

    /* Decode the route flags field */
    sub_ti = proto_tree_add_text(tree, tvb, offset, 1, "External Flags");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_extdata_flags);
    sub_tvb = tvb_new_subset_remaining(tvb, offset);

    proto_tree_add_item(sub_tree, hf_eigrp_extdata_flag_ext, sub_tvb, 0, 1,
                        ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_flag_cd, sub_tvb, 0, 1,
                        ENC_BIG_ENDIAN);

    offset += 1;
    return(offset);
}

/**
 *@fn int dissect_eigrp_metric_flags (proto_tree *tree, tvbuff_t *tvb, int offset, int limit)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 * @param[in] limit     maximum number of bytes which can be process
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect Protocol Dependent Module (PDM) Flags field in the route metric
 * section of an internal and external route. The following represents the
 * format of the bit field
 *
 *       MSB             LSB
 *    7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |   Flags       |    MP Flags   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *              | | |
 *              | | +- Route is Replicated
 *              | +--- Route is Active
 *              +----- Source Withdraw
 */
static int
dissect_eigrp_metric_flags (proto_tree *tree, tvbuff_t *tvb, int offset, int limit)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;

    /* Decode the route flags field */
    sub_ti = proto_tree_add_text(tree, tvb, offset, limit, "Flags");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_metric_flags);
    sub_tvb = tvb_new_subset(tvb, offset, limit, -1);

    /* just care about 'flags' byte, there are no MP flags for now */
    proto_tree_add_item(sub_tree, hf_eigrp_metric_flags_srcwd, sub_tvb, 0, 1,
                        ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_flags_active, sub_tvb, 0, 1,
                        ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_flags_repl, sub_tvb, 0, 1,
                        ENC_BIG_ENDIAN);

    offset += limit;
    return(offset);
}

/**
 *@fn int dissect_eigrp_ipv4_addr (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                 packet_info *pinfo, int offset, int unreachable)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect all IPv4 address from offset though the end of the packet
 */
static int
dissect_eigrp_ipv4_addr (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                         packet_info *pinfo, int offset, int unreachable)
{
    guint8      ip_addr[4], length;
    int         addr_len;
    proto_item *ti_prefixlen, *ti_dst;
    int         first = TRUE;

    for (; tvb_length_remaining(tvb, offset) > 0; offset += (1 + addr_len)) {
        length = tvb_get_guint8(tvb, offset);
        addr_len = ipv4_addr_and_mask(tvb, offset + 1, ip_addr, length);

        if (addr_len < 0) {
            ti_prefixlen = proto_tree_add_item(tree, hf_eigrp_ipv4_prefixlen,
                                               tvb, offset, 1, ENC_BIG_ENDIAN);
            expert_add_info_format(pinfo, ti_prefixlen, &ei_eigrp_prefixlen, "Invalid prefix length %u, must be <= 32", length);
            addr_len = 4; /* assure we can exit the loop */

        } else {
            proto_tree_add_item(tree, hf_eigrp_ipv4_prefixlen, tvb, offset, 1,
                                ENC_BIG_ENDIAN);
            offset += 1;
            ti_dst = proto_tree_add_text(tree, tvb, offset, addr_len,
                                         "Destination: %s", ip_to_str(ip_addr));

            /* add it to the top level line */
            proto_item_append_text(ti,"  %c   %s/%u", first ? '=':',',
                                   ip_to_str(ip_addr), length);

            if (unreachable) {
                expert_add_info(pinfo, ti_dst, &ei_eigrp_unreachable);
            }
        }
        first = FALSE;
    }
    return (offset);
}

/**
 *@fn int dissect_eigrp_ipv6_addr (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                 packet_info *pinfo, int offset, int unreachable)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect all IPv6 address from offset though the end of the packet
 */
static int
dissect_eigrp_ipv6_addr (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                         packet_info *pinfo, int offset, int unreachable)
{
    guint8             length;
    int                addr_len;
    struct e_in6_addr  addr;
    proto_item        *ti_prefixlen, *ti_dst;
    int                first = TRUE;

    for (; tvb_length_remaining(tvb, offset) > 0; offset += (1 + addr_len)) {
        length = tvb_get_guint8(tvb, offset);
        addr_len = ipv6_addr_and_mask(tvb, offset + 1, &addr, length);

        if (addr_len < 0) {
            ti_prefixlen = proto_tree_add_item(tree, hf_eigrp_ipv6_prefixlen,
                                               tvb, offset, 1, ENC_BIG_ENDIAN);
            expert_add_info_format(pinfo, ti_prefixlen, &ei_eigrp_prefixlen, "Invalid prefix length %u, must be <= 128", length);
            addr_len = 16; /* assure we can exit the loop */
        } else {
            proto_tree_add_item(tree, hf_eigrp_ipv6_prefixlen, tvb, offset, 1,
                                ENC_BIG_ENDIAN);
            offset += 1;

            if ((length < 128) && (length % 8 == 0)) {
                addr_len++;
            }

            ti_dst = proto_tree_add_text(tree, tvb, offset, addr_len,
                                         "Destination: %s", ip6_to_str(&addr));

            /* add it to the top level line */
            proto_item_append_text(ti,"  %c   %s/%u", first ? '=':',',
                                   ip6_to_str(&addr), length);

            if (unreachable) {
                expert_add_info(pinfo, ti_dst, &ei_eigrp_unreachable);
            }
        }
        first = FALSE;
    }
    return(offset);
}

/**
 *@fn int dissect_eigrp_ipx_addr (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                packet_info *pinfo, int offset, int unreachable)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect all IPX address from offset though the end of the packet
 */
static int
dissect_eigrp_ipx_addr (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                        packet_info *pinfo, int offset, int unreachable)
{
    proto_item *ti_dst;

    ti_dst = proto_tree_add_item(tree, hf_eigrp_ipx_dest, tvb, offset, 4,
                                 ENC_NA);

    /* add it to the top level line */
    proto_item_append_text(ti,"  =   %s",
                           tvb_ipxnet_to_string(tvb, offset));

    if (unreachable) {
        expert_add_info(pinfo, ti_dst, &ei_eigrp_unreachable);
    }

    offset +=4;
    return(offset);
}

/**
 *@fn int dissect_eigrp_service (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                               packet_info *pinfo, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect all SAF Services from offset though the end of the packet. The
 * following represents the format of  a SAF Service:
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |            Service            |         SubService            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                             GUID                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                             GUID(cont)                        |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                             GUID(cont)                        |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                             GUID(cont)                        |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |            Type               |           Length              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |        Reachability AFI       |    Reachability Port          |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |     Reachability Protocol     |    Reachability Addr          |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                      Reachability Addr(cont)                  |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                      Reachability Addr(cont)                  |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                      Reachability Addr(cont)                  |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |    Reachability Addr(cont)    |           Sequence            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |           Sequence(cont)      |\/\/\/    Service Data   \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 */
static int
dissect_eigrp_service (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                       packet_info *pinfo, int offset)
{
    int         afi, length, remaining;
    int         sub_offset;
    proto_item *sub_ti, *reach_ti;
    proto_tree *sub_tree, *reach_tree;
    tvbuff_t   *sub_tvb, *reach_tvb;
    guint16     service, sub_service;

    remaining = tvb_length_remaining(tvb, offset);
    sub_ti = proto_tree_add_text(tree, tvb, offset, remaining, "SAF Service ");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_tlv_metric);
    sub_tvb = tvb_new_subset(tvb, offset, remaining, -1);
    sub_offset = 0;

    for (; tvb_length_remaining(sub_tvb, sub_offset) > 0; ) {
        service = tvb_get_ntohs(sub_tvb, sub_offset);
        proto_item_append_text(sub_ti, "%c %s", (sub_offset == 0 ? '=':','),
                               val_to_str_const(service, eigrp_saf_srv2string, ""));

        sub_service = tvb_get_ntohs(sub_tvb, sub_offset+2);
        proto_item_append_text(ti, "%c %u:%u", (sub_offset == 0 ? '=':','),
                               service, sub_service);

        proto_tree_add_item(sub_tree, hf_eigrp_saf_service, sub_tvb,
                            sub_offset, 2, ENC_BIG_ENDIAN);
        sub_offset += 2;
        proto_tree_add_item(sub_tree, hf_eigrp_saf_subservice, sub_tvb,
                            sub_offset, 2, ENC_BIG_ENDIAN);
        sub_offset += 2;
        proto_tree_add_item(sub_tree, hf_eigrp_saf_guid, sub_tvb,
                            sub_offset, GUID_LEN, ENC_BIG_ENDIAN);
        sub_offset += GUID_LEN;

        proto_tree_add_item(sub_tree, hf_eigrp_saf_data_type, sub_tvb,
                            sub_offset, 2, ENC_BIG_ENDIAN);
        sub_offset += 2;
        length = tvb_get_ntohs(sub_tvb, sub_offset);
        proto_tree_add_item(sub_tree, hf_eigrp_saf_data_length, sub_tvb,
                            sub_offset, 2, ENC_BIG_ENDIAN);
        sub_offset += 2;

        /*
         * Reachability information
         */
        reach_ti = proto_tree_add_text(sub_tree, sub_tvb, sub_offset, 22,
                                       "Reachability");
        reach_tree = proto_item_add_subtree(reach_ti, ett_eigrp_saf_reachability);
        reach_tvb = tvb_new_subset(sub_tvb, sub_offset, 22, -1);

        afi = tvb_get_ntohs(reach_tvb, 0);
        proto_tree_add_item(reach_tree, hf_eigrp_saf_reachability_afi,
                            reach_tvb, 0, 2, ENC_BIG_ENDIAN);
        proto_tree_add_item(reach_tree, hf_eigrp_saf_reachability_port,
                            reach_tvb, 2, 2, ENC_BIG_ENDIAN);
        proto_tree_add_item(reach_tree, hf_eigrp_saf_reachability_protocol,
                            reach_tvb, 4, 2, ENC_BIG_ENDIAN);

        switch (afi) {
        case EIGRP_AF_IPv4:
            proto_tree_add_item(reach_tree, hf_eigrp_saf_reachability_addr_ipv4,
                                reach_tvb, 6, 4, ENC_BIG_ENDIAN);
            proto_tree_add_item(reach_tree, hf_eigrp_nullpad, reach_tvb, 10, 12,
                                ENC_NA);
            break;

        case EIGRP_AF_IPv6:
            proto_tree_add_item(reach_tree, hf_eigrp_saf_reachability_addr_ipv6,
                                reach_tvb, 6, 16, ENC_NA);
            break;
        default:
            /* just print zeros... */
            proto_tree_add_item(reach_tree, hf_eigrp_saf_reachability_addr_hex,
                                reach_tvb, 6, 16, ENC_NA);
            break;
        }
        sub_offset += 22;

        proto_tree_add_item(sub_tree, hf_eigrp_saf_data_sequence, sub_tvb,
                            sub_offset, 4, ENC_BIG_ENDIAN);
        sub_offset += 4;

        if (length > 0) {
            tvbuff_t *xml_tvb;
            guint8 *test_string, *tok;

            /*
             * Service-Data is usually (but not always) plain text, specifically
             * XML. If it "looks like" XML (begins with optional white-space
             * followed by a '<'), try XML. Otherwise, try plain-text.
             */
            xml_tvb = tvb_new_subset(sub_tvb, sub_offset, length, length);
            test_string = tvb_get_string(wmem_packet_scope(), xml_tvb, 0, (length < 32 ?
                                                                length : 32));
            tok = strtok(test_string, " \t\r\n");

            if (tok && tok[0] == '<') {
                /* Looks like XML */
                dissector_try_string(media_type_table, "application/xml",
                                     xml_tvb, pinfo, sub_tree, NULL);
            } else {
                /* Try plain text */
                dissector_try_string(media_type_table, "text/plain",
                                     xml_tvb, pinfo, sub_tree, NULL);
            }
        }
        sub_offset += length;
    }

    offset += sub_offset;
    return(offset);
}

/**
 *@fn int dissect_eigrp_legacy_metric (proto_tree *tree, tvbuff_t *tvb, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the TLV Versions 1.2 (legacy) and 3.0 (deprecated) metric
 * sections. The following represents the format
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Scaled Delay                            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                    Scaled Bandwidth                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         MTU                                    |   Hopcount   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   | Reliability  |      Load     |  Internal Tag   |    Flag      |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 */
static int
dissect_eigrp_legacy_metric (proto_tree *tree, tvbuff_t *tvb, int offset)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;

    sub_ti = proto_tree_add_text(tree, tvb, offset, 16, "Legacy Metric");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_tlv_metric);
    sub_tvb = tvb_new_subset(tvb, offset, 16, -1);

    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_delay, sub_tvb,
                        0, 4, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_bw, sub_tvb,
                        4, 4, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_mtu, sub_tvb,
                        8, 3, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_hopcount, sub_tvb,
                        11, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_rel, sub_tvb,
                        12, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_load, sub_tvb,
                        13, 1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_legacy_metric_intag, sub_tvb,
                        14, 1, ENC_BIG_ENDIAN);

    /* Decode the route flags field */
    dissect_eigrp_metric_flags(sub_tree, sub_tvb, 15, 1);

    offset += 16;
    return(offset);
}

/**
 *@fn int dissect_eigrp_ipx_extdata (proto_tree *tree, tvbuff_t *tvb, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the IPX External data for the TLV versions 1.2 and 3.0.
 * The following represents the format
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *                                   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *                                   |          Ext RouterID         |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Ext Router ID                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                Ext Autonomous System Number                   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                        Route Tag                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |  Ext Protocol  | Ext Flags    |     External Metric           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |      External Delay           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
static int
dissect_eigrp_ipx_extdata (proto_tree *tree, tvbuff_t *tvb, int offset)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;
    int         sub_offset = 0;

    sub_ti = proto_tree_add_text(tree, tvb, offset, 20, "External Data");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_tlv_extdata);
    sub_tvb = tvb_new_subset(tvb, offset, 20, -1);

    /* Decode the external route source info */
    proto_tree_add_item(sub_tree, hf_eigrp_ipx_extdata_routerid, sub_tvb,
                        sub_offset, 6, ENC_NA);
    sub_offset += 6;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_as, sub_tvb,
                        sub_offset, 4, ENC_BIG_ENDIAN);
    sub_offset += 4;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_tag, sub_tvb,
                        sub_offset, 4, ENC_BIG_ENDIAN);
    sub_offset += 4;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_proto, sub_tvb,
                        sub_offset, 1, ENC_BIG_ENDIAN);
    sub_offset += 1;

    /* Decode the external route flags */
    dissect_eigrp_extdata_flags(sub_tree, sub_tvb, sub_offset);
    sub_offset += 1;

    /* and the rest of it... */
    proto_tree_add_item(sub_tree, hf_eigrp_ipx_extdata_metric,
                        sub_tvb, sub_offset, 2, ENC_BIG_ENDIAN);
    sub_offset += 2;
    proto_tree_add_item(sub_tree, hf_eigrp_ipx_extdata_delay,
                        sub_tvb, sub_offset, 2, ENC_BIG_ENDIAN);
    sub_offset += 2;

    offset += sub_offset;
    return(offset);
}

/**
 *@fn int dissect_eigrp_extdata (proto_tree *tree, tvbuff_t *tvb, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the external route data for TLV versions 1.2 and 3.0 for all
 * protocols except IPX. The following represents the format
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Ext Router ID                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                Ext Autonomous System Number                   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                        Route Tag                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                    External Metric                            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         Reserved             |   Ext Protocol  | Ext Flags    |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
static int
dissect_eigrp_extdata (proto_tree *tree, tvbuff_t *tvb, int offset)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;
    int         sub_offset = 0;

    sub_ti = proto_tree_add_text(tree, tvb, offset, 20, "External Data");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_tlv_extdata);
    sub_tvb = tvb_new_subset(tvb, offset, 20, -1);

    /* Decode the external route source info */
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_origrid, sub_tvb,
                        sub_offset, 4, ENC_BIG_ENDIAN);
    sub_offset += 4;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_as, sub_tvb,
                        sub_offset, 4, ENC_BIG_ENDIAN);
    sub_offset += 4;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_tag, sub_tvb,
                        sub_offset, 4, ENC_BIG_ENDIAN);
    sub_offset += 4;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_metric, sub_tvb,
                        sub_offset, 4, ENC_BIG_ENDIAN);
    sub_offset += 4;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_reserved, sub_tvb,
                        sub_offset, 2, ENC_BIG_ENDIAN);
    sub_offset += 2;
    proto_tree_add_item(sub_tree, hf_eigrp_extdata_proto, sub_tvb,
                        sub_offset, 1, ENC_BIG_ENDIAN);
    sub_offset += 1;

    /* Decode the external route flags */
    dissect_eigrp_extdata_flags(sub_tree, sub_tvb, sub_offset);
    sub_offset += 1;

    offset += sub_offset;
    return(offset);
}

/**
 *@fn int dissect_eigrp_nexthop (proto_tree *tree, tvbuff_t *tvb, guint16 afi, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] afi       IANA address family indicator
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the next hop field which is in the "route TLVs".  This function will
 * handle all the various protocol AFIs and return the appropriate number of
 * bytes processed
 */
static int
dissect_eigrp_nexthop (proto_tree *tree, tvbuff_t *tvb, guint16 afi, int offset)
{
    /* dissect dest information */
    switch (afi) {
    case EIGRP_SF_IPv4:
    case EIGRP_AF_IPv4:
        proto_tree_add_item(tree, hf_eigrp_ipv4_nexthop, tvb, offset, 4,
                            ENC_BIG_ENDIAN);
        offset += 4;
        break;

    case EIGRP_SF_IPv6:
    case EIGRP_AF_IPv6:
        proto_tree_add_item(tree, hf_eigrp_ipv6_nexthop, tvb, offset, 16,
                            ENC_NA);
        offset += 16;
        break;

    case EIGRP_AF_IPX:
        proto_tree_add_item(tree, hf_eigrp_ipx_nexthop_net, tvb, offset, 4,
                            ENC_NA);
        offset += 4;
        proto_tree_add_item(tree, hf_eigrp_ipx_nexthop_host, tvb, offset, 6,
                            ENC_NA);
        offset += 6;
        break;

    case EIGRP_SF_COMMON:
        break;

    default:
        break;
    }

    return(offset);
}

/**
 *@fn void dissect_eigrp_general_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                    packet_info *pinfo, guint16 tlv)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 * @param[in] tlv       Specific TLV in to be dissected
 *
 * @par
 * General EIGRP parameters carry EIGRP management information and are not
 * specific to any one routed protocol.
 *
 */
static void
dissect_eigrp_general_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                           packet_info *pinfo, guint16 tlv)
{
    switch (tlv) {
    case EIGRP_TLV_PARAMETER:
        dissect_eigrp_parameter(tree, tvb, pinfo, ti);
        break;
    case EIGRP_TLV_AUTH:
        dissect_eigrp_auth_tlv(tree, tvb, pinfo, ti);
        break;
    case EIGRP_TLV_SEQ:
        dissect_eigrp_seq_tlv(tree, tvb, pinfo, ti);
        break;
    case EIGRP_TLV_SW_VERSION:
        dissect_eigrp_sw_version(tvb, tree, ti);
        break;
    case EIGRP_TLV_NEXT_MCAST_SEQ:
        dissect_eigrp_next_mcast_seq(tvb, tree, ti);
        break;
    case EIGRP_TLV_PEER_STUBINFO:
        dissect_eigrp_peer_stubinfo(tvb, tree);
        break;
    case EIGRP_TLV_PEER_TERMINATION:
        dissect_eigrp_peer_termination(pinfo, ti);
        break;
    case EIGRP_TLV_PEER_TIDLIST:
        dissect_eigrp_peer_tidlist(tree, tvb);
        break;
    default:
        expert_add_info_format(pinfo, ti, &ei_eigrp_tlv_type, "Unknown Generic TLV (0x%04x)", tlv);
        break;
    }
}

/**
 *@fn int dissect_eigrp_ipv4_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                 packet_info *pinfo, guint16 tlv)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] tlv       Specific TLV in to be dissected
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the Legacy IPv4 route TLV; handles both the internal and external
 * TLV types; This packet format is being deprecated and replaced with the
 * Multi-Protocol packet formats as of EIGRP Release-8.  This TLV format is used
 * to maintain backward compatibility between older version so EIGRP, "MTR"
 * EIGRP, and current shipping code.
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                      IPv4 Nexthop                             |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Scaled Delay                            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                    Scaled Bandwidth                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         MTU                                    |   Hopcount   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   | Reliability  |      Load     |  Internal Tag   |   Flag       |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
static int
dissect_eigrp_ipv4_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                        packet_info *pinfo, guint16 tlv)
{
    int offset      = 0;
    int unreachable = FALSE;

    proto_tree_add_item(tree, hf_eigrp_ipv4_nexthop, tvb, offset, 4,
                        ENC_BIG_ENDIAN);
    offset += 4;

    /* dissect external data if needed */
    if ((tlv & EIGRP_TLV_TYPEMASK) == EIGRP_TLV_EXTERNAL) {
        offset = dissect_eigrp_extdata(tree, tvb, offset);
    }

    /* dissect the metric */
    offset = dissect_eigrp_legacy_metric(tree, tvb, offset);

    /* dissect addresses */
    offset = dissect_eigrp_ipv4_addr(ti, tree, tvb, pinfo, offset, unreachable);

    return offset;
}

/**
 *@fn void dissect_eigrp_atalk_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                  proto_item *ti, guint16 tlv)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] tlv       Specific TLV in to be dissected
 *
 * @par
 * Dissect the legacy AppleTalk route TLV; handles both the internal and external
 * TLV type.  The following represents the format
 */
static void
dissect_eigrp_atalk_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                         guint16 tlv)
{
    int offset = 0;

    /* cable tlv? */
    if (EIGRP_TLV_AT_CBL == tlv) {
        proto_tree_add_text(tree, tvb, 0, 4, "AppleTalk Cable Range = %u-%u",
                            tvb_get_ntohs(tvb, 0), tvb_get_ntohs(tvb, 2));
        proto_tree_add_item(tree, hf_eigrp_atalk_routerid, tvb, 4, 4,
                            ENC_BIG_ENDIAN);
        proto_item_append_text(ti, ": Cable range= %u-%u, Router ID= %u",
                               tvb_get_ntohs(tvb, 0), tvb_get_ntohs(tvb, 2),
                               tvb_get_ntohl(tvb, 4));

    } else {
        proto_tree_add_text(tree, tvb, offset, 4, "NextHop Address = %u.%u",
                            tvb_get_ntohs(tvb, 0), tvb_get_ntohs(tvb, 2));
        offset += 4;

        /* dissect external data if needed */
        if ((tlv & EIGRP_TLV_TYPEMASK) == EIGRP_TLV_EXTERNAL) {
            offset = dissect_eigrp_extdata(tree, tvb,offset);
        }

        /* dissect the metric */
        offset = dissect_eigrp_legacy_metric(tree, tvb, offset);

        /* dissect cable range */
        proto_tree_add_text(tree, tvb, offset, 4, "Cable range = %u-%u",
                            tvb_get_ntohs(tvb, 36), tvb_get_ntohs(tvb, 38));
        proto_item_append_text(ti, ": %u-%u",
                               tvb_get_ntohs(tvb, 36), tvb_get_ntohs(tvb, 38));
    }
    return;
}

/**
 *@fn void dissect_eigrp_ipv6_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                 packet_info *pinfo, guint16 tlv)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] tlv       Specific TLV in to be dissected
 *
 * @par
 * Dissect the Legacy IPv6 route TLV; handles both the internal and external
 * TLV types; This packet format is being deprecated and replaced with the
 * Multi-Protocol packet formats as of EIGRP Release-8.  This TLV format is used
 * to maintain backward compatibility between older version so EIGRP, "MTR"
 * EIGRP, and current shipping code.
 */
static void
dissect_eigrp_ipv6_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                        packet_info *pinfo, guint16 tlv)
{
    int offset      = 0;
    int unreachable = FALSE;

    proto_tree_add_item(tree, hf_eigrp_ipv6_nexthop, tvb, offset, 16,
                        ENC_NA);
    offset += 16;

    /* dissect external data if needed */
    if ((tlv & EIGRP_TLV_TYPEMASK) == EIGRP_TLV_EXTERNAL) {
        offset = dissect_eigrp_extdata(tree, tvb, offset);
    }

    /* dissect the metric */
    offset = dissect_eigrp_legacy_metric(tree, tvb, offset);

    /* dissect addresses */
    dissect_eigrp_ipv6_addr(ti, tree, tvb, pinfo, offset, unreachable);
    return;
}

/**
 *@fn int dissect_eigrp_ipx_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                packet_info *pinfo, guint16 tlv)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] tlv       Specific TLV in to be dissected
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the legacy IPX route TLV; handles both the internal and external
 * TLV type.  The following represents the format
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                         Nexthop Net                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                        Nexthop Host                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |  Nexthop Host(cont)           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * Optional External Data:
 *                                   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *                                   |          Ext RouterID         |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Ext Router ID                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                Ext Autonomous System Number                   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                        Route Tag                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |  Ext Protocol  | Ext Flags    |    External Metric            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |     External Delay            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *                                   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *                                   |           Scaled Delay        |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |           Scaled Delay        |      Scaled Bandwidth         |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         Scaled Bandwidth      |             MTU               |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |   MTU(cont)   |    Hopcount   | Reliability   |     Load      |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   | Internal Tag |      Flag      |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *
 */
static int
dissect_eigrp_ipx_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                       packet_info *pinfo, guint16 tlv)
{
    int offset      = 0;
    int unreachable = FALSE;

    /* nexthop for route... */
    offset = dissect_eigrp_nexthop(tree, tvb, EIGRP_AF_IPX, offset);

    /* dissect external data if needed */
    if ((tlv & EIGRP_TLV_TYPEMASK) == EIGRP_TLV_EXTERNAL) {
        offset = dissect_eigrp_ipx_extdata(tree, tvb, offset);
    }

    /* dissect the metric */
    offset = dissect_eigrp_legacy_metric(tree, tvb, offset);

    /* dissect addresses */
    offset = dissect_eigrp_ipx_addr(ti, tree, tvb, pinfo, offset, unreachable);

    return offset;
}

/**
 *@fn void dissect_eigrp_ipv4_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                 packet_info *pinfo, proto_item *ti, guint16 tlv)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in] ti        protocol item
 * @param[in] tlv       Specific TLV in to be dissected
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the Multi-Topology route TLV; This packet format has been deprecated
 * and replaced with the Multi-Protocol packet formats as of EIGRP Release-8. Of
 * course this means it will be around for a long long while. The following
 * represents the format
 *
 *    1       2                   3   0                   1         1
 *    6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
 *                                   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *                                   |           Reserved            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |   Topology Identifier         |       Family Identifier       |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Router ID                               |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Route Tag                               |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Scaled Delay                            |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                    Scaled Bandwidth                           |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         MTU                                    |   Hopcount   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   | Reliability  |      Load      |  Internal Tag   |    Flag     |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/         NextHop (Family Specific Length)          \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/          External Route Data (Optional)           \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/       Destination (Family Specific Length)        \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 */
static int
dissect_eigrp_multi_topology_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                                  packet_info *pinfo, guint16 tlv)
{
    guint16     afi;
    int         offset      = 2;
    int         unreachable = FALSE;

    /* tid for you */
    proto_tree_add_item(tree, hf_eigrp_tid, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    /* now it's all about the family */
    afi = tvb_get_ntohs(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_afi, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    /* gota have an id... */
    proto_tree_add_item(tree, hf_eigrp_routerid, tvb, offset, 4, ENC_BIG_ENDIAN);
    offset += 4;

    /* tag.. your it! */
    proto_tree_add_item(tree, hf_eigrp_legacy_metric_tag, tvb, offset, 4, ENC_BIG_ENDIAN);
    offset += 4;

    /* dissect the metric */
    offset = dissect_eigrp_legacy_metric(tree, tvb, offset);

    /* dissect nexthop */
    offset = dissect_eigrp_nexthop(tree, tvb, afi, offset);

    /* dissect external data if needed */
    if ((tlv & EIGRP_TLV_TYPEMASK) == EIGRP_TLV_EXTERNAL) {
        if (afi == EIGRP_AF_IPX) {
            offset = dissect_eigrp_ipx_extdata(tree, tvb, offset);
        } else {
            offset = dissect_eigrp_extdata(tree, tvb, offset);
        }
    }

    /* dissect dest information */
    switch (afi) {
    case EIGRP_AF_IPv4:
        offset = dissect_eigrp_ipv4_addr(ti, tree, tvb, pinfo, offset, unreachable);
        break;
    case EIGRP_AF_IPv6:
        offset = dissect_eigrp_ipv6_addr(ti, tree, tvb, pinfo, offset, unreachable);
        break;
    case EIGRP_AF_IPX:
        offset = dissect_eigrp_ipx_addr(ti, tree, tvb, pinfo, offset, unreachable);
        break;

    case EIGRP_SF_COMMON:
    case EIGRP_SF_IPv4:
    case EIGRP_SF_IPv6:
        offset = dissect_eigrp_service(ti, tree, tvb, pinfo, offset);
        break;

    default:
        proto_tree_add_expert(tree, pinfo, &ei_eigrp_afi, tvb, offset, -1);
    }

    return offset;
}

/**
 *@fn int dissect_eigrp_metric_comm (proto_tree *tree, tvbuff_t *tvb, int offset, int limit)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 * @param[in] limit     maximum number of bytes which can be process
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect extended community attached to metric TLVs to support VPNv4
 * deployments, The following represents the format
 *
 *   0                   1                   2                   3
 *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |  Type high    |  Type low(*)  |                               |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+          Value                |
 *  |                                                               |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
static int
dissect_eigrp_metric_comm (proto_tree *tree, tvbuff_t *tvb, int offset, int limit)
{
    int comm_type;

    while (limit > 0) {
        comm_type = tvb_get_ntohs(tvb, offset);
        offset++;

        switch (comm_type) {
            /*
             * Tag for this route. It is present for all EIGRP VPNv4
             * routes, internal and external
             */
        case EIGRP_EXTCOMM_EIGRP:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_EIGRP): Flag(0x%02x) Tag(%u)",
                                tvb_get_ntohs(tvb, 0),
                                tvb_get_ntohl(tvb, 2));
            break;
        case EIGRP_EXTCOMM_VRR:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_VRR)): RES(0x%02x) RID(0x%04x)",
                                tvb_get_ntohs(tvb, 0),
                                tvb_get_ntohl(tvb, 2));
            break;

            /*
             * Vecmetric information for given EIGRP VPNv4 route,
             * applies to both internal and external
             */
        case EIGRP_EXTCOMM_DAD:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_DAD): AS(%u):SDLY(%u)",
                                tvb_get_ntohs(tvb, 0),
                                tvb_get_ntohl(tvb, 2));
            break;
        case EIGRP_EXTCOMM_VRHB:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_VRHB): REL(%u) HOP(%u) SBW(%u)",
                                tvb_get_guint8(tvb, 0),
                                tvb_get_guint8(tvb, 1),
                                tvb_get_ntohl(tvb, 2));
            break;
        case EIGRP_EXTCOMM_SRLM:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_SRLM): RES(%u) LOAD(%u) MTU(%u)",
                                tvb_get_guint8(tvb, 0),
                                tvb_get_guint8(tvb, 1),
                                tvb_get_ntohl(tvb, 2));
            break;

            /*
             * External information for given EIGRP VPNv4 route,
             * applies to only to external routes
             */
        case EIGRP_EXTCOMM_SAR:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_SAR): xAS(%u) xRID(%u)",
                                tvb_get_ntohs(tvb, 0),
                                tvb_get_ntohl(tvb, 2));
            break;
        case EIGRP_EXTCOMM_RPM:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_RPM): xProto(%u) xMETRIC(%u)",
                                tvb_get_ntohs(tvb, 0),
                                tvb_get_ntohl(tvb, 2));
            break;

        case EIGRP_EXTCOMM_SOO_ASFMT:
        case EIGRP_EXTCOMM_SOO_ADRFMT:
            proto_tree_add_text(tree, tvb, offset, 8,
                                "Type(EIGRP_EXTCOMM_SOO): AS(%u) TAG(%u)",
                                tvb_get_ntohs(tvb, 0),
                                tvb_get_ntohl(tvb, 2));
            break;
        }

        /*on to the next */
        offset += 8;
        limit -= 8;

        if (0 != limit%8) {
            break;
        }

    }

    return(offset);
}

/**
 *@fn int dissect_eigrp_wide_metric_attr (proto_tree *tree, tvbuff_t *tvb,
 *                                        int offset, int limit)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 * @param[in] limit     maximum number of words which should be process
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the Metric Attributes which (optionally) are part of the wide-metric
 * route TLV.  Some of the attributes which effect the metric are controlled by
 * K6 which is now part of the Parameter TLV.  Also, eh extended community TLV is
 * no longer used, as it's now appended to the route
 */
static int
dissect_eigrp_wide_metric_attr (proto_tree *tree, tvbuff_t *tvb,
                                int offset, int limit)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;
    int         sub_offset;

    guint16 attr_offset = 0;
    guint8  attr_opcode = 0;

    limit *= 2;   /* words to bytes */

    sub_ti     = proto_tree_add_text(tree, tvb, offset, limit, "Attributes");
    sub_tree   = proto_item_add_subtree(sub_ti, ett_eigrp_tlv_attr);
    sub_tvb    = tvb_new_subset(tvb, offset, limit, -1);
    sub_offset = 0;

    while (limit > 0) {
        attr_opcode = tvb_get_guint8(sub_tvb, sub_offset);
        proto_tree_add_item(sub_tree, hf_eigrp_attr_opcode, sub_tvb,
                            sub_offset, 1, ENC_BIG_ENDIAN);
        sub_offset += 1;

        attr_offset = tvb_get_guint8(sub_tvb, sub_offset) * 2;
        proto_tree_add_item(sub_tree, hf_eigrp_attr_offset, sub_tvb,
                            sub_offset, 1, ENC_BIG_ENDIAN);
        sub_offset += 1;

        switch (attr_opcode) {
        case EIGRP_ATTR_NOOP:
            break;

        case EIGRP_ATTR_SCALED:
            proto_tree_add_item(sub_tree, hf_eigrp_attr_scaled, sub_tvb,
                                sub_offset, 4, ENC_BIG_ENDIAN);
            break;

        case EIGRP_ATTR_TAG:
            proto_tree_add_item(sub_tree, hf_eigrp_attr_tag, sub_tvb,
                                sub_offset, 4, ENC_BIG_ENDIAN);
            break;

        case EIGRP_ATTR_COMM:
            dissect_eigrp_metric_comm(sub_tree,
                                      tvb_new_subset(sub_tvb, sub_offset, 8, -1),
                                      sub_offset, limit);
            break;

        case EIGRP_ATTR_JITTER:
            proto_tree_add_item(sub_tree, hf_eigrp_attr_jitter, sub_tvb,
                                sub_offset, 4, ENC_BIG_ENDIAN);
            break;

        case EIGRP_ATTR_QENERGY:
            proto_tree_add_item(sub_tree, hf_eigrp_attr_qenergy, sub_tvb,
                                sub_offset, 4, ENC_BIG_ENDIAN);
            break;

        case EIGRP_ATTR_ENERGY:
            proto_tree_add_item(sub_tree, hf_eigrp_attr_energy, sub_tvb,
                                sub_offset, 4, ENC_BIG_ENDIAN);
            break;

        default:
            break;
        }
        sub_offset += attr_offset;
        limit -= (EIGRP_ATTR_HDRLEN + attr_offset);
    }

    offset += sub_offset;
    return(offset);
}

/**
 *@fn int dissect_eigrp_wide_metric (proto_tree *tree, tvbuff_t *tvb, int offset)
 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] offset    current byte offset in packet being processed
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the latest-n-greatest "Wide"Metric" definition for EIGRP. This
 * definition was created to address the higher speed links and should handle
 * things until we break the speed of light *wink*
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |    Offset    |   Priority     |  Reliability  |     Load      |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         MTU                                    |   Hopcount   |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                            Delay                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         Delay                 |         Bandwidth             |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                        Bandwidth                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |         Reserved              |           Flags               |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/        Extended Metrics (Variable Length)         \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 */
static int
dissect_eigrp_wide_metric (proto_tree *tree, tvbuff_t *tvb, int offset)
{
    proto_item *sub_ti;
    proto_tree *sub_tree;
    tvbuff_t   *sub_tvb;
    gint8       attr_size = 0;
    guint64     big_num;

    sub_ti = proto_tree_add_text(tree, tvb, offset, 24, "Wide Metric");
    sub_tree = proto_item_add_subtree(sub_ti, ett_eigrp_tlv_metric);
    sub_tvb = tvb_new_subset(tvb, offset, 24, -1);

    attr_size = tvb_get_guint8(sub_tvb, 0);

    proto_tree_add_item(sub_tree, hf_eigrp_metric_offset,
                        sub_tvb, 0,  1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_priority,
                        sub_tvb, 1,  1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_rel,
                        sub_tvb, 2,  1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_load,
                        sub_tvb, 3,  1, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_mtu,
                        sub_tvb, 4,  3, ENC_BIG_ENDIAN);
    proto_tree_add_item(sub_tree, hf_eigrp_metric_hopcount,
                        sub_tvb, 7,  1, ENC_BIG_ENDIAN);

    /* The one-way latency along an unloaded path to the destination
     * expressed in units of nanoseconds per kilobyte. This number is not
     * scaled, as is the case with scaled delay. A delay of 0xFFFFFFFFFFFF
     * indicates an unreachable route. */
    big_num = tvb_get_ntoh64(sub_tvb, 8);
    big_num >>= 16;
    if (big_num == G_GUINT64_CONSTANT(0x0000ffffffffffff)) {
        proto_tree_add_text(sub_tree, sub_tvb, 8, 6, "Delay: Infinity");
    } else {
        proto_tree_add_text(sub_tree, sub_tvb, 8, 6, "Delay: %" G_GINT64_MODIFIER "u", big_num);
    }

    /* The path bandwidth measured in kilobyte per second as presented by
     * the interface.  This number is not scaled, as is the case with scaled
     * bandwidth. A bandwidth of 0xFFFFFFFFFFFF indicates an unreachable
     * route.
     */
    big_num = tvb_get_ntoh64(sub_tvb, 14);
    big_num >>= 16;
    if (big_num == G_GUINT64_CONSTANT(0x0000ffffffffffff)) {
        proto_tree_add_text(sub_tree, sub_tvb, 14, 6, "Bandwidth: Infinity");
    } else {
        proto_tree_add_text(sub_tree, sub_tvb, 14, 6, "Bandwidth: %" G_GINT64_MODIFIER "u", big_num);
    }
    proto_tree_add_item(sub_tree, hf_eigrp_metric_reserved, sub_tvb, 20, 2,
                        ENC_BIG_ENDIAN);

    /* Decode the route flags field */
    dissect_eigrp_metric_flags(sub_tree, sub_tvb, 22, 2);
    offset += 24;

    /* any extended metric attributes? */
    if (attr_size > 0) {
        offset = dissect_eigrp_wide_metric_attr(tree, tvb, offset, attr_size);
    }

    return(offset);
}

/**
 *@fn int dissect_eigrp_multi_protocol_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
 *                                           packet_info *pinfo, guint16 tlv)

 *
 * @param[in,out] tree  detail dissection result
 * @param[in] tvb       packet data
 * @param[in] ti        protocol item
 * @param[in] pinfo     general data about the protocol
 *
 * @return int          number of bytes process
 *
 * @par
 * Dissect the Multi-Protocol (TLV Version 2.0) TLV format definition. The following
 * represents the format
 *
 *    0                   1                   2                   3
 *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |   Topology Identifier         |         Family Identifier     |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                       Router ID                               |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |                      Wide Metric                              |
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/        Extended Metrics (Variable Length)         \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/         NextHop (Family Specific Length)          \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/          External Route Data (Optional)           \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *   |\/\/\/       Destination (Family Specific Length)        \/\/\/|
 *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
static int
dissect_eigrp_multi_protocol_tlv (proto_item *ti, proto_tree *tree, tvbuff_t *tvb,
                                  packet_info *pinfo, guint16 tlv)
{
    int         offset      = 0;
    guint16     afi;
    int         unreachable = FALSE;

    /* tid for you */
    proto_tree_add_item(tree, hf_eigrp_tid, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    /* now it's all about the family */
    afi = tvb_get_ntohs(tvb, offset);
    proto_tree_add_item(tree, hf_eigrp_afi, tvb, offset, 2, ENC_BIG_ENDIAN);
    offset += 2;

    /* gota have an id... */
    proto_tree_add_item(tree, hf_eigrp_routerid, tvb, offset, 4, ENC_BIG_ENDIAN);
    offset += 4;

    /* decode the wide metric */
    offset = dissect_eigrp_wide_metric(tree, tvb, offset);

    /* dissect nexthop */
    offset = dissect_eigrp_nexthop(tree, tvb, afi, offset);

    /* dissect external data if needed */
    if ((tlv & EIGRP_TLV_TYPEMASK) == EIGRP_TLV_EXTERNAL) {
        if (afi == EIGRP_AF_IPX) {
            offset = dissect_eigrp_ipx_extdata(tree, tvb, offset);
        } else {
            offset = dissect_eigrp_extdata(tree, tvb, offset);
        }
    }

    /* dissect dest information */
    switch (afi) {
    case EIGRP_AF_IPv4:
        offset = dissect_eigrp_ipv4_addr(ti, tree, tvb, pinfo, offset, unreachable);
        break;

    case EIGRP_AF_IPv6:
        offset = dissect_eigrp_ipv6_addr(ti, tree, tvb, pinfo, offset, unreachable);
        break;

    case EIGRP_AF_IPX:
        offset = dissect_eigrp_ipx_addr(ti, tree, tvb, pinfo, offset, unreachable);
        break;

    case EIGRP_SF_COMMON:
    case EIGRP_SF_IPv4:
    case EIGRP_SF_IPv6:
        offset = dissect_eigrp_service(ti, tree, tvb, pinfo, offset);
        break;

    default:
        proto_tree_add_expert(tree, pinfo, &ei_eigrp_afi, tvb, offset, -1);
    }

    return offset;
}

/**
 *@fn int dissect_eigrp (proto_tree *tree, tvbuff_t *tvb, packet_info *pinfo, void *data)
 *
 * @param[in] tvb       packet data
 * @param[in] pinfo     general data about the protocol
 * @param[in,out] tree  detail dissection result
 *
 * @return int          0 if packet is not for this decoder
 *
 * @par
 * This function is called to dissect the packets presented to it. The packet
 * data is held in a special buffer referenced here as tvb. The packet info
 * structure contains general data about the protocol, and can update
 * information here. The tree parameter is where the detail dissection takes
 * place.
 */
#include <epan/in_cksum.h>

static guint16 ip_checksum(const guint8 *ptr, int len)
{
    vec_t cksum_vec[1];

    cksum_vec[0].ptr = ptr;
    cksum_vec[0].len = len;
    return in_cksum(&cksum_vec[0], 1);
}
static int
dissect_eigrp (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
{
    proto_item *ti;
    proto_tree *eigrp_tree        = NULL, *tlv_tree;
    guint       opcode, vrid;
    guint16     tlv, checksum, cacl_checksum;
    guint32     ack, size, offset = EIGRP_HEADER_LENGTH;

    /* Make entries in Protocol column and Info column on summary display */
    col_set_str(pinfo->cinfo, COL_PROTOCOL, "EIGRP");

    /* This field shows up as the "Info" column in the display; you should use
     * it, if possible, to summarize what's in the packet, so that a user
     * looking at the list of packets can tell what type of packet it is. See
     * section 1.5 for more information.
     */
    col_clear(pinfo->cinfo, COL_INFO);

    opcode = tvb_get_guint8(tvb, 1);
    ack    = tvb_get_ntohl(tvb, 12);
    if ((opcode == EIGRP_OPC_HELLO) && (0 != ack)) {
        opcode = EIGRP_OPC_ACK;
    }

    col_add_str(pinfo->cinfo, COL_INFO,
                val_to_str(opcode, eigrp_opcode2string, "Unknown OpCode (0x%04x)"));

    /* A protocol dissector may be called in 2 different ways - with, or
     * without a non-null "tree" argument.
     * Note also that there is no guarantee, the first time the dissector is
     * called, whether "tree" will be null or not; your dissector must work
     * correctly, building or updating whatever state information is necessary,
     * in either case.
     */
    /* NOTE: The offset and length values in the call to
     * "proto_tree_add_item()" define what data bytes to highlight in the
     * hex display window when the line in the protocol tree display
     * corresponding to that item is selected.
     */

    /* create display subtree for the protocol */
    ti = proto_tree_add_protocol_format(tree, proto_eigrp, tvb, 0, -1,
                                        "Cisco EIGRP");
    eigrp_tree = proto_item_add_subtree(ti, ett_eigrp);
    proto_tree_add_item(eigrp_tree, hf_eigrp_version, tvb, 0, 1,
                        ENC_BIG_ENDIAN);
    proto_tree_add_item(eigrp_tree, hf_eigrp_opcode, tvb, 1, 1,
                        ENC_BIG_ENDIAN);

    size          = tvb_length(tvb);
    checksum      = tvb_get_ntohs(tvb, 2);
    cacl_checksum = ip_checksum(tvb_get_ptr(tvb, 0, size), size);

    if (cacl_checksum == checksum) {
        proto_tree_add_text(eigrp_tree, tvb, 2, 2,
                            "Checksum: 0x%02x [incorrect]",
                            checksum);
        expert_add_info(pinfo, ti, &ei_eigrp_checksum_bad);
    } else {
        proto_tree_add_text(eigrp_tree, tvb, 2, 2,
                            "Checksum: 0x%02x [correct]", checksum);
    }

    /* Decode the EIGRP Flags Field */
    proto_tree_add_bitmask(eigrp_tree, tvb, 4, hf_eigrp_flags, ett_eigrp_flags,
                           eigrp_flag_fields, ENC_BIG_ENDIAN);

    proto_tree_add_item(eigrp_tree, hf_eigrp_sequence, tvb, 8, 4,
                        ENC_BIG_ENDIAN);
    proto_tree_add_item(eigrp_tree, hf_eigrp_acknowledge, tvb, 12, 4,
                        ENC_BIG_ENDIAN);

    /* print out what family we dealing with... */
    ti = proto_tree_add_item(eigrp_tree, hf_eigrp_vrid, tvb, 16, 2,
                             ENC_BIG_ENDIAN);
    vrid = (tvb_get_ntohs(tvb, 16) & EIGRP_VRID_MASK);
    proto_item_append_text(ti, " %s", val_to_str_const(vrid, eigrp_vrid2string, ""));

    /* print autonomous-system */
    proto_tree_add_item(eigrp_tree, hf_eigrp_as, tvb, 18, 2,
                        ENC_BIG_ENDIAN);

    switch (opcode) {
    case EIGRP_OPC_IPXSAP:
        call_dissector(ipxsap_handle,
                       tvb_new_subset_remaining(tvb, EIGRP_HEADER_LENGTH), pinfo,
                       eigrp_tree);
        break;

    default:
        while (tvb_reported_length_remaining(tvb, offset) > 0) {
            tlv = tvb_get_ntohs(tvb, offset);

            /* it's a rose by the wrong name... */
            if (tlv == EIGRP_TLV_MTR_TIDLIST) {
                tlv = EIGRP_TLV_PEER_TIDLIST;
            }

            size =  tvb_get_ntohs(tvb, offset + 2);
            if (size == 0) {
                proto_tree_add_expert(eigrp_tree, pinfo, &ei_eigrp_tlv_len, tvb, offset, -1);
                return(tvb_length(tvb));
            }

            ti = proto_tree_add_text(eigrp_tree, tvb, offset, size, "%s",
                                     val_to_str(tlv, eigrp_tlv2string, "Unknown TLV (0x%04x)"));

            tlv_tree = proto_item_add_subtree(ti, ett_eigrp_tlv);
            proto_tree_add_item(tlv_tree, hf_eigrp_tlv_type, tvb,
                                offset, 2, ENC_BIG_ENDIAN);
            proto_tree_add_item(tlv_tree, hf_eigrp_tlv_len, tvb,
                                (offset + 2), 2, ENC_BIG_ENDIAN);

            switch (tlv & EIGRP_TLV_RANGEMASK) {
            case EIGRP_TLV_GENERAL:
                dissect_eigrp_general_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)), pinfo, tlv);
                break;

            case EIGRP_TLV_IPv4:
                dissect_eigrp_ipv4_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)), pinfo, tlv);
                break;

            case EIGRP_TLV_ATALK:
                dissect_eigrp_atalk_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)), tlv);
                break;

            case EIGRP_TLV_IPX:
                dissect_eigrp_ipx_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)), pinfo, tlv);
                break;

            case EIGRP_TLV_IPv6:
                dissect_eigrp_ipv6_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)), pinfo, tlv);
                break;

            case EIGRP_TLV_MP:
                dissect_eigrp_multi_protocol_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)),
                                                 pinfo, tlv);
                break;

            case EIGRP_TLV_MTR:
                dissect_eigrp_multi_topology_tlv(ti, tlv_tree, tvb_new_subset_length(tvb, (offset + 4), (size - 4)),
                                                 pinfo, tlv);
                break;

            default:
                expert_add_info_format(pinfo, ti, &ei_eigrp_tlv_type, "Unknown TLV Group (0x%04x)", tlv);
            }

            offset += size;
        }
        break;
    }

    /* Return the amount of data this dissector was able to dissect */
    return(tvb_length(tvb));
}

/**
 *@fn void proto _ register _ eigrp (void)
 *
 * @usage
 *      you can not have the function name inside a comment or else Wireshark
 *      will fail with "duplicate protocol" error.  Dont you hate it when tools
 *      try to be to smart :(
 *
 * @par
 *      Register the protocol with Wireshark
 *      this format is require because a script is used to build the C function
 *      that calls all the protocol registration.
 */
void
proto_register_eigrp(void)
{
    /* Setup list of header fields  See Section 1.6.1 for details
     */
    static hf_register_info hf[] = {
        /*
         *
         * EIGRP Packet Header definitions
         *
         *    0                   1                   2                   3
         *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
         *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         *   |Ver              |  Opcode       |          Checksum           |
         *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         *   |                          Flags                                |
         *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         *   |                      Sequence number                          |
         *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         *   |                    Acknowledgement number                     |
         *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         *   |  Virtual Router ID              | Autonomous system number    |
         *   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         */
        { &hf_eigrp_version,
          { "Version", "eigrp.version",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Version - Version of EIGRP packet format", HFILL }
        },
        { &hf_eigrp_opcode,
          { "Opcode", "eigrp.opcode",
            FT_UINT8, BASE_DEC, VALS(eigrp_opcode2string), 0x0,
            "Opcode - Operation code indicating the message type", HFILL }
        },
        { &hf_eigrp_flags,
          { "Flags", "eigrp.flags",
            FT_UINT32, BASE_HEX, NULL, 0x0,
            "Flag - Initialization bit and is used in establishing "
            "a new neighbor relationship", HFILL }
        },
        { &hf_eigrp_sequence,
          { "Sequence", "eigrp.seq",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "Sequence number -- used to send messages reliably", HFILL }
        },
        { &hf_eigrp_acknowledge,
          { "Acknowledge", "eigrp.ack",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "Acknowledge number -- used to send messages reliably", HFILL }
        },
        { &hf_eigrp_vrid,
          { "Virtual Router ID", "eigrp.vrid",
            FT_UINT16, BASE_DEC, NULL, 0,
            "Virtual Router ID - For each Virtual Router, there is a separate topology "
            "table and routing/service table; even for matching AS. "
            "This field allows the gateway to select which set router to use.", HFILL }
        },
        { &hf_eigrp_as,
          { "Autonomous System", "eigrp.as",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Autonomous system number - Each AS has a separate topology table "
            "which for a give routing/service table. A gateway can participate "
            "in more than one AS. This field allows the gateway to"
            "select which set of topology tables to use.", HFILL }
        },

        /*
         * Define eigrp_flags bits here
         *
         * Init bit definition. First unicast transmitted Update has this
         * bit set in the flags field of the fixed header. It tells the neighbor
         * to send its full topology table.
         */
        { &hf_eigrp_flags_init,
          { "Init", "eigrp.flags.init",
            FT_BOOLEAN, 32, TFS(&tfs_set_notset), EIGRP_INIT_FLAG,
            "Init - tells the neighbor to send its full topology table", HFILL }
        },

        /*
         * Conditionally Received - Any packet with the CR-bit set can
         * be accepted by an EIGRP speaker if and only if a previous Hello was
         * received with the SEQUENCE_TYPE TLV present.
         * This allows multicasts to be transmitted in order and reliably at the
         * same time as unicasts are transmitted.
         */
        { &hf_eigrp_flags_condrecv,
          { "Conditional Receive", "eigrp.flags.condrecv",
            FT_BOOLEAN, 32, TFS(&tfs_set_notset), EIGRP_CR_FLAG,
            "Conditionally Received the next packet if address was in listed "
            "in the previous HELLO", HFILL }
        },

        /*
         * Restart flag is set in the hello and the init update
         * packets during the nsf signaling period.  A nsf-aware
         * router looks at the RS flag to detect if a peer is restarting
         * and maintain the adjacency. A restarting router looks at
         * this flag to determine if the peer is helping out with the restart.
         */
        { &hf_eigrp_flags_restart,
          { "Restart", "eigrp.flags.restart",
            FT_BOOLEAN, 32, TFS(&tfs_set_notset), EIGRP_RS_FLAG,
            "Restart flag - Set in the HELLO and the initial "
            "UPDATE packets during the nsf signaling period.", HFILL },
        },

        /*
         * EOT bit.  The End-of-Table flag marks the end of the start-up updates
         * sent to a new peer.  A nsf restarting router looks at this flag to
         * determine if it has finished receiving the start-up updates from all
         * peers.  A nsf-aware router waits for this flag before cleaning up
         * the stale routes from the restarting peer.
         */
        { &hf_eigrp_flags_eot,
          { "End Of Table", "eigrp.flags.eot",
            FT_BOOLEAN, 32, TFS(&tfs_set_notset), EIGRP_EOT_FLAG,
            "End-of-Table - Marks the end of the start-up UPDATES indicating the "
            "complete topology database has been sent to a new peer", HFILL }
        },

        /**
         * TLV type definitions.  Generic (protocol-independent) TLV types are
         * defined here.  Protocol-specific ones are defined later
         *
         *     +-----+------------------+
         *     |     |     |            |
         *     | Type| Len |    Vector  |
         *     |     |     |            |
         *     +-----+------------------+
         *
         * TLV type definitions.  Generic (protocol-independent) TLV types are
         * defined here.  Protocol-specific ones are defined elsewhere.
         *
         * EIGRP_PARAMETER              0x0001          parameter
         * EIGRP_AUTH                   0x0002          authentication
         * EIGRP_SEQUENCE               0x0003          sequenced packet
         * EIGRP_SW_VERSION             0x0004          software version
         * EIGRP_NEXT_MCAST_SEQ         0x0005          multicast sequence
         * EIGRP_PEER_STUBINFO          0x0006          stub information
         * EIGRP_PEER_TERMINATION       0x0007          peer termination
         */
        { &hf_eigrp_tlv_type,
          { "Type", "eigrp.tlv_type",
            FT_UINT16, BASE_HEX, VALS(eigrp_tlv2string), 0x0,
            "TLV Type", HFILL }
        },
        { &hf_eigrp_tlv_len,
          { "Length", "eigrp.tlv.len",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "TLV Length", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Parameters TLV
 */
        { &hf_eigrp_par_k1, { "K1", "eigrp.par.k1", FT_UINT8, BASE_DEC, NULL, 0x0,
                              "Bandwidth/Throughput Coefficient", HFILL }},
        { &hf_eigrp_par_k2, { "K2", "eigrp.par.k2", FT_UINT8, BASE_DEC, NULL, 0x0,
                              "Load Coefficient", HFILL }},
        { &hf_eigrp_par_k3, { "K3", "eigrp.par.k3", FT_UINT8, BASE_DEC, NULL, 0x0,
                              "Delay/Latency Coefficient", HFILL }},
        { &hf_eigrp_par_k4, { "K4", "eigrp.par.k4", FT_UINT8, BASE_DEC, NULL, 0x0,
                              "Reliability Coefficient", HFILL }},
        { &hf_eigrp_par_k5, { "K5", "eigrp.par.k5", FT_UINT8, BASE_DEC, NULL, 0x0,
                              "Reliability Coefficient", HFILL }},
        { &hf_eigrp_par_k6, { "K6", "eigrp.par.k6", FT_UINT8, BASE_DEC, NULL, 0x0,
                              "Extended Metric Coefficient", HFILL }},
        { &hf_eigrp_par_holdtime,
          { "Hold Time", "eigrp.par.holdtime", FT_UINT16, BASE_DEC, NULL, 0x0,
            "How long to ignore lost HELLO's", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Authentication TLV
 */
        { &hf_eigrp_auth_type,
          { "Type", "eigrp.auth.type",
            FT_UINT16, BASE_DEC, VALS(eigrp_auth2string), 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_auth_len,
          { "Length", "eigrp.auth.length",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_auth_keyid,
          { "Key ID", "eigrp.auth.keyid",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_auth_keyseq,
          { "Key Sequence", "eigrp.auth.keyseq",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_auth_digest,
          { "Digest", "eigrp.auth.digest",
            FT_BYTES, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Sequence TLV
 */
        { &hf_eigrp_seq_addrlen,
          { "Address length", "eigrp.seq.addrlen",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_seq_ipv4addr,
          { "IP Address", "eigrp.seq.ipv4addr",
            FT_IPv4, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_seq_ipv6addr,
          { "IPv6 Address", "eigrp.seq.ipv6addr",
            FT_IPv6, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Next Multicast Sequence
 */
        /*
         * This was added to the hello containing the sequence TLV so that the
         * hello packet could be more tightly bound to the multicast packet bearing
         * the CR bit that follows it.  The sequence number of the impending multicast
         * is carried herein.
         */
        { &hf_eigrp_next_mcast_seq,
          { "Multicast Sequence", "eigrp.next_mcast_seq",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Peer Stub Information TLV
 */
        { &hf_eigrp_stub_flags,
          { "Stub Options", "eigrp.stub_options",
            FT_UINT16, BASE_HEX, NULL, 0x0,
            NULL, HFILL }
        },

        /*
         * Define eigrp_stub_flags bits here
         */
        { &hf_eigrp_stub_flags_connected,
          { "Connected", "eigrp.stub_options.connected",
            FT_BOOLEAN, 16, TFS(&tfs_set_notset), EIGRP_PEER_ALLOWS_CONNECTED,
            NULL, HFILL }
        },
        { &hf_eigrp_stub_flags_static,
          { "Static", "eigrp.stub_options.static",
            FT_BOOLEAN, 16, TFS(&tfs_set_notset), EIGRP_PEER_ALLOWS_STATIC,
            NULL, HFILL }
        },
        { &hf_eigrp_stub_flags_summary,
          { "Summary", "eigrp.stub_options.summary",
            FT_BOOLEAN, 16, TFS(&tfs_set_notset), EIGRP_PEER_ALLOWS_SUMMARY,
            NULL, HFILL }
        },
        { &hf_eigrp_stub_flags_redist,
          { "Redistributed", "eigrp.stub_options.redist",
            FT_BOOLEAN, 16, TFS(&tfs_set_notset), EIGRP_PEER_ALLOWS_REDIST,
            NULL, HFILL }
        },
        { &hf_eigrp_stub_flags_leakmap,
          { "Leak-Map", "eigrp.stub_options.leakmap",
            FT_BOOLEAN, 16, TFS(&tfs_set_notset), EIGRP_PEER_ALLOWS_LEAKING,
            NULL, HFILL }
        },
        { &hf_eigrp_stub_flags_recvonly,
          { "Receive-Only", "eigrp.stub_options.recvonly",
            FT_BOOLEAN, 16, TFS(&tfs_set_notset), EIGRP_PEER_ALLOWS_RCVONLY,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Peer Termination TLV
 */
        /* Place holder - this TLV has no options */

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * EIGRP 3.0 Vector Header  (deprecated)
 */
        /*
         * common header for all version 3 tlvs
         */
        { &hf_eigrp_tid,
          { "Topology", "eigrp.tid",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_afi,
          { "AFI", "eigrp.afi",
            FT_UINT16, BASE_DEC, VALS(eigrp_afi2string), 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * EIGRP TLV 1.2 (legacy) and TLV 3.0 Metric (deprecated) definition
 */
        { &hf_eigrp_legacy_metric_delay,
          { "Scaled Delay", "eigrp.old_metric.delay",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "delay, in 39.1 nanosec interments", HFILL }
        },
        { &hf_eigrp_legacy_metric_bw,
          { "Scaled BW", "eigrp.old_metric.bw",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "bandwidth, in units of 1 Kbit/sec", HFILL }
        },
        { &hf_eigrp_legacy_metric_mtu,
          { "MTU", "eigrp.old_metric.mtu",
            FT_UINT24, BASE_DEC, NULL, 0x0,
            "MTU, in octets", HFILL }
        },
        { &hf_eigrp_legacy_metric_hopcount,
          { "Hop Count", "eigrp.old_metric.hopcount",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Number of hops to destination", HFILL }
        },
        { &hf_eigrp_legacy_metric_rel,
          { "Reliability", "eigrp.old_metric.rel",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "percent packets successfully tx/rx", HFILL }
        },
        { &hf_eigrp_legacy_metric_load,
          { "Load", "eigrp.old_metric.load",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "percent of channel occupied", HFILL }
        },
        { &hf_eigrp_legacy_metric_intag,
          { "Route Tag", "eigrp.old_metric.intag",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Internal Route Tag", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * EIGRP 3.0 TIDLIST TLV  (only survivor in MTR)
 */
        { &hf_eigrp_tidlist_tid,
          { "TID List", "eigrp.tidlist",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_tidlist_flags,
          { "TID List Flags", "eigrp.tidlist.flags",
            FT_UINT16, BASE_HEX, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_tidlist_len,
          { "TID List Size", "eigrp.tidlist.len",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_routerid,
          { "RouterID", "eigrp.routerid",
            FT_IPv4, BASE_NONE, NULL, 0x0,
            "Router ID of injecting router", HFILL }
        },
        { &hf_eigrp_legacy_metric_tag,
          { "Tag", "eigrp.old_metric.tag",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "route tag", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * PDM opaque flag field definitions
 */
        { &hf_eigrp_metric_flags_srcwd,
          { "Source Withdraw", "eigrp.metric.flags.srcwd",
            FT_BOOLEAN, 8, TFS(&tfs_true_false), EIGRP_OPAQUE_SRCWD,
            "Route Source Withdraw", HFILL }
        },
        { &hf_eigrp_metric_flags_active,
          { "Route is Active", "eigrp.metric.flags.active",
            FT_BOOLEAN, 8, TFS(&tfs_true_false), EIGRP_OPAQUE_ACTIVE,
            "Route is currently in active state", HFILL }
        },
        { &hf_eigrp_metric_flags_repl,
          { "Route is Replicated", "eigrp.metric.flags.repl",
            FT_BOOLEAN, 8, TFS(&tfs_true_false), EIGRP_OPAQUE_REPL,
            "Route is replicated from different tableid", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * EIGRP TLV 1.2/3.0 ExtData Definitions
 */
        { &hf_eigrp_extdata_origrid,
          { "Originating RouterID", "eigrp.extdata.origrid",
            FT_IPv4, BASE_NONE, NULL, 0x0,
            "Router ID of redistributing router", HFILL }
        },

        { &hf_eigrp_extdata_as,
          { "Originating A.S.", "eigrp.extdata.as",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "Autonomous System of redistributing protocol", HFILL }
        },

        { &hf_eigrp_extdata_tag,
          { "Administrative Tag", "eigrp.extdata.tag",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "Administrative Route Tag", HFILL }
        },
        { &hf_eigrp_extdata_metric,
          { "External Metric", "eigrp.extdata.metric",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            "Metric reported by redistributing protocol", HFILL }
        },
        { &hf_eigrp_extdata_reserved,
          { "Reserved", "eigrp.extdata.reserved",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },

        /* IPX ExtData Definitions */
        { &hf_eigrp_ipx_extdata_delay,
          { "External Delay", "eigrp.extdata.ipx_delay",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Delay reported by redistributing protocol", HFILL }
        },
        { &hf_eigrp_ipx_extdata_metric,
          { "External Metric", "eigrp.extdata.ipx_metric",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Delay reported by redistributing protocol", HFILL }
        },

        { &hf_eigrp_extdata_proto,
          { "External Protocol ID", "eigrp.extdata.proto",
            FT_UINT8, BASE_DEC, VALS(eigrp_proto2string), 0x0,
            NULL, HFILL }
        },

        { &hf_eigrp_extdata_flag_ext,
          { "Route is External", "eigrp.opaque.flag.ext",
            FT_BOOLEAN, 8, TFS(&tfs_true_false), EIGRP_OPAQUE_EXT,
            "External route", HFILL }
        },
        { &hf_eigrp_extdata_flag_cd,
          { "Route is Candidate Default", "eigrp.opaque.flag.cd",
            FT_BOOLEAN, 8, TFS(&tfs_true_false), EIGRP_OPAQUE_CD,
            "Candidate-Default route", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * EIGRP TLV 2.0 "Wide" Metric format definition
 */
        /* Number of 16bit words in the metric section, used to determine the
         * start of the destination/attribute information.
         */
        { &hf_eigrp_metric_offset,
          { "Offset", "eigrp.metric.offset",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Number of 16bit words to reach the start of the"
            "destination/attribute information", HFILL }
        },

        /* Priority of the prefix when transmitting a group of destination
         * addresses to neighboring routers. A priority of zero indicates no
         * priority is set.
         */
        { &hf_eigrp_metric_priority,
          { "Priority", "eigrp.metric.priority",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Priority of the prefix for ordering transmission", HFILL }
        },

        /** The current error rate for the path. Measured as an error
         * percentage. A value of 255 indicates 100% reliability
         */
        { &hf_eigrp_metric_rel,
          { "Reliability", "eigrp.metric.reliability",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "percent packets successfully tx/rx", HFILL }
        },

        /** The load utilization of the path to the destination. Measured as a
         * percentage of load. A value of 255 indicates 100% load.
         */
        { &hf_eigrp_metric_load,
          { "Load", "eigrp.metric.load",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "percent of channel occupied", HFILL }
        },

        /** The minimum maximum transmission unit size for the path to the
         * destination. Not used in metric calculation, but available to
         * underlying protocols
         */
        { &hf_eigrp_metric_mtu,
          { "MTU", "eigrp.metric.mtu",
            FT_UINT24, BASE_DEC, NULL, 0x0,
            "MTU, in octets", HFILL }
        },

        /** number of router traversals to the destination */
        { &hf_eigrp_metric_hopcount,
          { "Hop Count", "eigrp.metric.hopcount",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Number of hops to destination", HFILL }
        },

        /* Reserved - Transmitted as 0x0000 */
        { &hf_eigrp_metric_reserved,
          { "Reserved", "eigrp.metric.reserved",
            FT_UINT16, BASE_HEX, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * EIGRP TLV 2.0 Extended Metric Attributes
 */
        { &hf_eigrp_attr_opcode,
          { "Opcode", "eigrp.attr.opcode",
            FT_UINT8, BASE_DEC, VALS(eigrp_attr_opcode2string), 0x0,
            "Opcode - Operation code indicating the attribute type", HFILL }
        },
        { &hf_eigrp_attr_offset,
          { "Offset", "eigrp.attr.offset",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            "Number of 2 byte words of data", HFILL }
        },
        { &hf_eigrp_attr_scaled,
          { "Legacy Metric", "eigrp.attr.scaled",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Metric calculated from legacy TLVs", HFILL }
        },
        { &hf_eigrp_attr_tag,
          { "Tag", "eigrp.attr.tag",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Tag assigned by admin for dest", HFILL }
        },
        { &hf_eigrp_attr_jitter,
          { "Jitter", "eigrp.attr.jitter",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Variation in path delay", HFILL }
        },
        { &hf_eigrp_attr_qenergy,
          { "Q-Energy", "eigrp.attr.qenergy",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Non-Active energy usage along path", HFILL }
        },
        { &hf_eigrp_attr_energy,
          { "Energy", "eigrp.attr.energy",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            "Active energy usage along path", HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * IPv4 specific address definitions
 */
        { &hf_eigrp_ipv4_nexthop,
          { "NextHop", "eigrp.ipv4.nexthop",
            FT_IPv4, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_ipv4_prefixlen,
          { "Prefix Length", "eigrp.ipv4.prefixlen",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * IPv6 specific address definitions
 */
        { &hf_eigrp_ipv6_nexthop,
          { "NextHop", "eigrp.ipv6.nexthop",
            FT_IPv6, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },

        { &hf_eigrp_ipv6_prefixlen,
          { "Prefix Length", "eigrp.ipv6.prefixlen",
            FT_UINT8, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * IPX specific address definitions
 */
        { &hf_eigrp_ipx_nexthop_net,
          { "NextHop Net", "eigrp.ipx.nexthop_net",
            FT_IPXNET, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_ipx_nexthop_host,
          { "NextHop Host", "eigrp.ipx.nexthop_host",
            FT_ETHER, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_ipx_extdata_routerid,
          { "External RouterID", "eigrp.ipx.routerid",
            FT_ETHER, BASE_NONE, NULL, 0x0,
            "Router ID of redistributing router", HFILL }
        },
        { &hf_eigrp_ipx_dest,
          { "Destination", "eigrp.ipx.dest",
            FT_IPXNET, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * AppleTalk specific address definitions
 */
        { &hf_eigrp_atalk_routerid,
          { "AppleTalk Router ID", "eigrp.atalk.routerid",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Service Advertisement Framework definitions
 */
        { &hf_eigrp_saf_service,
          { "Service", "eigrp.saf.service",
            FT_UINT16, BASE_DEC, VALS(eigrp_saf_srv2string), 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_subservice,
          { "Sub-Service", "eigrp.saf.subservice",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_guid,
          { "GUID", "eigrp.saf.guid",
            FT_GUID, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_data_type,
          { "Type", "eigrp.saf.data.type",
            FT_UINT16, BASE_HEX, VALS(eigrp_saf_type2string), 0x0,
            "SAF Message Data Type", HFILL }
        },
        { &hf_eigrp_saf_data_length,
          { "Length", "eigrp.saf.data.length",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_data_sequence,
          { "Sequence", "eigrp.saf.data.sequence",
            FT_UINT32, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_reachability_afi,
          { "AFI", "eigrp.saf.data.reachability.afi",
            FT_UINT16, BASE_DEC, VALS(eigrp_afi2string), 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_reachability_port,
          { "Port", "eigrp.saf.data.reachability.port",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_reachability_protocol,
          { "Protocol", "eigrp.saf.data.reachability.protocol",
            FT_UINT16, BASE_DEC, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_reachability_addr_ipv4,
          { "IPv4 Addr", "eigrp.saf.data.reachability.addr_ipv4",
            FT_IPv4, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_reachability_addr_ipv6,
          { "IPv6 Addr", "eigrp.saf.data.reachability.addr_ipv6",
            FT_IPv6, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
        { &hf_eigrp_saf_reachability_addr_hex,
          { "Addr", "eigrp.saf.data.reachability.addr_hex",
            FT_BYTES, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },

        /* misc field used in a couple places */
        { &hf_eigrp_nullpad,
          { "Nullpad", "eigrp.nullpad",
            FT_BYTES, BASE_NONE, NULL, 0x0,
            NULL, HFILL }
        },
    };

    /* Setup protocol subtree array */
    static gint *ett[] = {
        /* header flag */
        &ett_eigrp,
        &ett_eigrp_flags,

        /* tlv specific */
        &ett_eigrp_tlv,
        &ett_eigrp_tlv_metric,
        &ett_eigrp_tlv_attr,
        &ett_eigrp_tlv_extdata,

        &ett_eigrp_tidlist,
        &ett_eigrp_stub_flags,
        &ett_eigrp_saf_reachability,

        /* metric tlv specific */
        &ett_eigrp_metric_flags,
        &ett_eigrp_extdata_flags,
    };

    static ei_register_info ei[] = {
        { &ei_eigrp_peer_termination, { "eigrp.peer_termination", PI_RESPONSE_CODE, PI_NOTE, "Peer Termination", EXPFILL }},
        { &ei_eigrp_auth_len, { "eigrp.auth.length.invalid", PI_MALFORMED, PI_WARN, "Invalid auth len", EXPFILL }},
        { &ei_eigrp_auth_type, { "eigrp.auth.type.invalid", PI_PROTOCOL, PI_WARN, "Invalid auth type", EXPFILL }},
        { &ei_eigrp_seq_addrlen, { "eigrp.seq.addrlen.invalid", PI_MALFORMED, PI_ERROR, "Invalid address length", EXPFILL }},
        { &ei_eigrp_peer_termination_graceful, { "eigrp.peer_termination_graceful", PI_RESPONSE_CODE, PI_NOTE, "Peer Termination (Graceful Shutdown)", EXPFILL }},
        { &ei_eigrp_prefixlen, { "eigrp.prefixlen.invalid", PI_MALFORMED, PI_WARN, "Invalid prefix length", EXPFILL }},
        { &ei_eigrp_unreachable, { "eigrp.unreachable", PI_RESPONSE_CODE, PI_NOTE, "Unreachable", EXPFILL }},
        { &ei_eigrp_tlv_type, { "eigrp.tlv_type.unknown", PI_PROTOCOL, PI_WARN, "Unknown TLV", EXPFILL }},
        { &ei_eigrp_afi, { "eigrp.afi.unknown", PI_PROTOCOL, PI_WARN, "Unknown AFI", EXPFILL }},
        { &ei_eigrp_checksum_bad, { "eigrp.checksum.bad", PI_CHECKSUM, PI_WARN, "Bad Checksum", EXPFILL }},
        { &ei_eigrp_tlv_len, { "eigrp.tlv.len.invalid", PI_MALFORMED, PI_ERROR, "Corrupt TLV (Length field set to 0)", EXPFILL }},
        { &ei_eigrp_tlv_trunc, { "eigrp.tlv.truncated", PI_MALFORMED, PI_ERROR, "Corrupt TLV (Truncated prematurely)", EXPFILL }},
    };

    expert_module_t* expert_eigrp;

    /* Register the protocol name and description */
    proto_eigrp = proto_register_protocol(
        "Enhanced Interior Gateway Routing Protocol",   /* name         */
        "EIGRP",                                        /* short name   */
        "eigrp"                                         /* abbrev       */
        );

    /* Required function calls to register the header fields and subtrees used */
    proto_register_field_array(proto_eigrp, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));
    expert_eigrp = expert_register_protocol(proto_eigrp);
    expert_register_field_array(expert_eigrp, ei, array_length(ei));
}

/**
 *@fn void proto_reg_handoff_eigrp(void)
 *
 * @usage
 * This exact format is required because a script is used to find these
 * routines and create the code that calls these routines.
 *
 * @par
 * If this dissector uses sub-dissector registration add a registration routine.
 *
 * This form of the reg_handoff function is used if if you perform registration
 * functions which are dependent upon prefs.  If this function is registered as
 * a prefs callback (see prefs_register_protocol above) this function is also
 * called by preferences whenever "Apply" is pressed;
 *
 * In that case, it should accommodate being called more than once.
 */
void
proto_reg_handoff_eigrp(void)
{
    dissector_handle_t eigrp_handle;

    ipxsap_handle = find_dissector("ipxsap");
    media_type_table = find_dissector_table("media_type");

    eigrp_handle = new_create_dissector_handle(dissect_eigrp, proto_eigrp);

    dissector_add_uint("ip.proto", IP_PROTO_EIGRP, eigrp_handle);
    dissector_add_uint("ddp.type", DDP_EIGRP, eigrp_handle);
    dissector_add_uint("ipx.socket", IPX_SOCKET_EIGRP, eigrp_handle);
}
