wireshark/epan/dissectors/packet-ipv6.c

/* packet-ipv6.c
 * Routines for IPv6 packet disassembly
 *
 * $Id$
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SHIM6 support added by Matthijs Mekking <matthijs@NLnetLabs.nl>
 *
 * MobileIPv6 support added by Tomislav Borosa <tomislav.borosa@siemens.hr>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

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

#include <string.h>
#include <math.h>
#include <stdio.h>
#include <glib.h>
#include <epan/packet.h>
#include "packet-ipsec.h"
#include "packet-ipv6.h"
#include <epan/ip_opts.h>
#include <epan/addr_resolv.h>
#include <epan/prefs.h>
#include <epan/reassemble.h>
#include <epan/ipproto.h>
#include <epan/ipv6-utils.h>
#include <epan/etypes.h>
#include <epan/ppptypes.h>
#include <epan/aftypes.h>
#include <epan/nlpid.h>
#include <epan/arcnet_pids.h>
#include <epan/in_cksum.h>
#include <epan/value_string.h>
#include <epan/expert.h>
#include <epan/emem.h>

/*
 * NOTE: ipv6.nxt is not very useful as we will have chained header.
 * now testing ipv6.final, but it raises SEGV.
#define TEST_FINALHDR
 */

/* Differentiated Services Field. See RFCs 2474, 2597 and 2598. */
#define IPDSFIELD_DSCP_MASK     0xFC
#define IPDSFIELD_ECN_MASK     0x03
#define IPDSFIELD_DSCP_SHIFT	2
#define IPDSFIELD_DSCP(dsfield)	(((dsfield)&IPDSFIELD_DSCP_MASK)>>IPDSFIELD_DSCP_SHIFT)
#define IPDSFIELD_ECN(dsfield)	((dsfield)&IPDSFIELD_ECN_MASK)
#define IPDSFIELD_DSCP_DEFAULT  0x00
#define IPDSFIELD_DSCP_CS1      0x08
#define IPDSFIELD_DSCP_CS2      0x10
#define IPDSFIELD_DSCP_CS3      0x18
#define IPDSFIELD_DSCP_CS4      0x20
#define IPDSFIELD_DSCP_CS5      0x28
#define IPDSFIELD_DSCP_CS6      0x30
#define IPDSFIELD_DSCP_CS7      0x38
#define IPDSFIELD_DSCP_AF11     0x0A
#define IPDSFIELD_DSCP_AF12     0x0C
#define IPDSFIELD_DSCP_AF13     0x0E
#define IPDSFIELD_DSCP_AF21     0x12
#define IPDSFIELD_DSCP_AF22     0x14
#define IPDSFIELD_DSCP_AF23     0x16
#define IPDSFIELD_DSCP_AF31     0x1A
#define IPDSFIELD_DSCP_AF32     0x1C
#define IPDSFIELD_DSCP_AF33     0x1E
#define IPDSFIELD_DSCP_AF41     0x22
#define IPDSFIELD_DSCP_AF42     0x24
#define IPDSFIELD_DSCP_AF43     0x26
#define IPDSFIELD_DSCP_EF       0x2E
#define IPDSFIELD_ECT_MASK	0x02
#define IPDSFIELD_CE_MASK	0x01

static int proto_ipv6		  = -1;
static int hf_ipv6_version	  = -1;
static int hf_ip_version      = -1;
static int hf_ipv6_class	  = -1;
static int hf_ipv6_flow		  = -1;
static int hf_ipv6_plen		  = -1;
static int hf_ipv6_nxt		  = -1;
static int hf_ipv6_hlim		  = -1;
static int hf_ipv6_src		  = -1;
static int hf_ipv6_src_host	  = -1;
static int hf_ipv6_dst		  = -1;
static int hf_ipv6_dst_host	  = -1;
static int hf_ipv6_addr		  = -1;
static int hf_ipv6_host		  = -1;
static int hf_ipv6_opt_pad1	  = -1;
static int hf_ipv6_opt_padn	  = -1;
static int hf_ipv6_dst_opt	  = -1;
static int hf_ipv6_hop_opt	  = -1;
static int hf_ipv6_unk_hdr	  = -1;
static int hf_ipv6_routing_hdr_opt	  = -1;
static int hf_ipv6_routing_hdr_type	  = -1;
static int hf_ipv6_routing_hdr_left	  = -1;
static int hf_ipv6_routing_hdr_addr	  = -1;
#ifdef TEST_FINALHDR
static int hf_ipv6_final	  = -1;
#endif
static int hf_ipv6_frag_offset		      = -1;
static int hf_ipv6_frag_more		      = -1;
static int hf_ipv6_frag_id		      = -1;
static int hf_ipv6_fragments		      = -1;
static int hf_ipv6_fragment		      = -1;
static int hf_ipv6_fragment_overlap	      = -1;
static int hf_ipv6_fragment_overlap_conflict  = -1;
static int hf_ipv6_fragment_multiple_tails    = -1;
static int hf_ipv6_fragment_too_long_fragment = -1;
static int hf_ipv6_fragment_error	      = -1;
static int hf_ipv6_reassembled_in	      = -1;

static int hf_ipv6_mipv6_type		      = -1;
static int hf_ipv6_mipv6_length		      = -1;
static int hf_ipv6_mipv6_home_address	      = -1;

static int hf_ipv6_shim6	      = -1;
static int hf_ipv6_shim6_nxt	      = -1;
static int hf_ipv6_shim6_len	      = -1;
static int hf_ipv6_shim6_p	      = -1;
/* context tag is 49 bits, cannot be used for filter yet */
static int hf_ipv6_shim6_ct	      = -1;
static int hf_ipv6_shim6_type	      = -1;
static int hf_ipv6_shim6_proto	      = -1;
static int hf_ipv6_shim6_checksum     = -1;
static int hf_ipv6_shim6_checksum_bad = -1;
static int hf_ipv6_shim6_checksum_good= -1;
static int hf_ipv6_shim6_inonce	      = -1; /* also for request nonce */
static int hf_ipv6_shim6_rnonce	      = -1;
static int hf_ipv6_shim6_precvd	      = -1;
static int hf_ipv6_shim6_psent	      = -1;
static int hf_ipv6_shim6_psrc	      = -1;
static int hf_ipv6_shim6_pdst	      = -1;
static int hf_ipv6_shim6_pnonce	      = -1;
static int hf_ipv6_shim6_pdata	      = -1;
static int hf_ipv6_shim6_sulid	      = -1;
static int hf_ipv6_shim6_rulid	      = -1;
static int hf_ipv6_shim6_reap	      = -1;
static int hf_ipv6_shim6_opt_type     = -1;
static int hf_ipv6_shim6_opt_len      = -1;
static int hf_ipv6_shim6_opt_total_len= -1;
static int hf_ipv6_shim6_opt_loc_verif_methods = -1;
static int hf_ipv6_shim6_opt_critical = -1;
static int hf_ipv6_shim6_opt_loclist  = -1;
static int hf_ipv6_shim6_locator      = -1;
static int hf_ipv6_shim6_loc_flag     = -1;
static int hf_ipv6_shim6_loc_prio     = -1;
static int hf_ipv6_shim6_loc_weight   = -1;
static int hf_ipv6_shim6_opt_locnum   = -1;
static int hf_ipv6_shim6_opt_elemlen  = -1;
static int hf_ipv6_shim6_opt_fii      = -1;
static int hf_ipv6_traffic_class_dscp = -1;
static int hf_ipv6_traffic_class_ect  = -1;
static int hf_ipv6_traffic_class_ce   = -1;

static gint ett_ipv6			  = -1;
static gint ett_ipv6_version	= -1;
static gint ett_ipv6_shim6		  = -1;
static gint ett_ipv6_shim6_option	  = -1;
static gint ett_ipv6_shim6_locators	  = -1;
static gint ett_ipv6_shim6_verif_methods  = -1;
static gint ett_ipv6_shim6_loc_pref	  = -1;
static gint ett_ipv6_shim6_probes_sent	  = -1;
static gint ett_ipv6_shim6_probe_sent	  = -1;
static gint ett_ipv6_shim6_probes_rcvd	  = -1;
static gint ett_ipv6_shim6_probe_rcvd	  = -1;
static gint ett_ipv6_shim6_cksum	  = -1;
static gint ett_ipv6_fragments		  = -1;
static gint ett_ipv6_fragment		  = -1;
static gint ett_ipv6_traffic_class        = -1;

static const fragment_items ipv6_frag_items = {
	&ett_ipv6_fragment,
	&ett_ipv6_fragments,
	&hf_ipv6_fragments,
	&hf_ipv6_fragment,
	&hf_ipv6_fragment_overlap,
	&hf_ipv6_fragment_overlap_conflict,
	&hf_ipv6_fragment_multiple_tails,
	&hf_ipv6_fragment_too_long_fragment,
	&hf_ipv6_fragment_error,
	&hf_ipv6_reassembled_in,
	"fragments"
};

static dissector_handle_t data_handle;

static dissector_table_t ip_dissector_table;

/* Reassemble fragmented datagrams */
static gboolean ipv6_reassemble = TRUE;

#ifndef offsetof
#define	offsetof(type, member)	((size_t)(&((type *)0)->member))
#endif

/*
 * defragmentation of IPv6
 */
static GHashTable *ipv6_fragment_table = NULL;
static GHashTable *ipv6_reassembled_table = NULL;

void
capture_ipv6(const guchar *pd, int offset, int len, packet_counts *ld)
{
  guint8 nxt;
  int advance;

  if (!BYTES_ARE_IN_FRAME(offset, len, 4+4+16+16)) {
    ld->other++;
    return;
  }
  nxt = pd[offset+6];		/* get the "next header" value */
  offset += 4+4+16+16;		/* skip past the IPv6 header */

again:
   switch (nxt) {
   case IP_PROTO_HOPOPTS:
   case IP_PROTO_ROUTING:
   case IP_PROTO_DSTOPTS:
     if (!BYTES_ARE_IN_FRAME(offset, len, 2)) {
       ld->other++;
       return;
     }
     nxt = pd[offset];
     advance = (pd[offset+1] + 1) << 3;
     if (!BYTES_ARE_IN_FRAME(offset, len, advance)) {
       ld->other++;
       return;
     }
     offset += advance;
     goto again;
   case IP_PROTO_FRAGMENT:
     if (!BYTES_ARE_IN_FRAME(offset, len, 2)) {
       ld->other++;
       return;
     }
     nxt = pd[offset];
     advance = 8;
     if (!BYTES_ARE_IN_FRAME(offset, len, advance)) {
       ld->other++;
       return;
     }
     offset += advance;
     goto again;
   case IP_PROTO_AH:
     if (!BYTES_ARE_IN_FRAME(offset, len, 2)) {
       ld->other++;
       return;
     }
     nxt = pd[offset];
     advance = 8 + ((pd[offset+1] - 1) << 2);
     if (!BYTES_ARE_IN_FRAME(offset, len, advance)) {
       ld->other++;
       return;
     }
     offset += advance;
     goto again;
   case IP_PROTO_SHIM6:
   case IP_PROTO_SHIM6_OLD:
     if (!BYTES_ARE_IN_FRAME(offset, len, 2)) {
       ld->other++;
       return;
     }
     nxt = pd[offset];
     advance = (pd[offset+1] + 1) << 3;
     if (!BYTES_ARE_IN_FRAME(offset, len, advance)) {
       ld->other++;
       return;
     }
     offset += advance;
     goto again;
   }

  switch(nxt) {
    case IP_PROTO_SCTP:
      ld->sctp++;
      break;
    case IP_PROTO_TCP:
      ld->tcp++;
      break;
    case IP_PROTO_UDP:
    case IP_PROTO_UDPLITE:
      ld->udp++;
      break;
    case IP_PROTO_ICMP:
    case IP_PROTO_ICMPV6:	/* XXX - separate counters? */
      ld->icmp++;
      break;
    case IP_PROTO_OSPF:
      ld->ospf++;
      break;
    case IP_PROTO_GRE:
      ld->gre++;
      break;
    case IP_PROTO_VINES:
      ld->vines++;
      break;
    default:
      ld->other++;
  }
}

static void
ipv6_reassemble_init(void)
{
  fragment_table_init(&ipv6_fragment_table);
  reassembled_table_init(&ipv6_reassembled_table);
}

enum {
  IPv6_RT_HEADER_SOURCE_ROUTING=0,
  IPv6_RT_HEADER_NIMROD,
  IPv6_RT_HEADER_MobileIP
};

/* Routeing Header Types */
static const value_string routing_header_type[] = {
  { IPv6_RT_HEADER_SOURCE_ROUTING, "IPv6 Source Routing" },
  { IPv6_RT_HEADER_NIMROD, "Nimrod" },
  { IPv6_RT_HEADER_MobileIP, "Mobile IP" },
  { 0, NULL }
};

static int
dissect_routing6(tvbuff_t *tvb, int offset, proto_tree *tree, packet_info *pinfo) {
    struct ip6_rthdr rt;
    guint len;
    proto_tree *rthdr_tree;
    proto_item *ti;
    guint8 buf[sizeof(struct ip6_rthdr0) + sizeof(struct e_in6_addr) * 23];

    tvb_memcpy(tvb, (guint8 *)&rt, offset, sizeof(rt));
    len = (rt.ip6r_len + 1) << 3;

    if (tree) {
	/* !!! specify length */
      ti = proto_tree_add_uint_format(tree, hf_ipv6_routing_hdr_opt, tvb,
		      offset, len, rt.ip6r_type,
		      "Routing Header, Type : %s (%u)",
		      val_to_str(rt.ip6r_type, routing_header_type, "Unknown"),
		      rt.ip6r_type);
      rthdr_tree = proto_item_add_subtree(ti, ett_ipv6);

	proto_tree_add_text(rthdr_tree, tvb,
	    offset + offsetof(struct ip6_rthdr, ip6r_nxt), 1,
	    "Next header: %s (0x%02x)", ipprotostr(rt.ip6r_nxt), rt.ip6r_nxt);

	proto_tree_add_text(rthdr_tree, tvb,
	    offset + offsetof(struct ip6_rthdr, ip6r_len), 1,
	    "Length: %u (%d bytes)", rt.ip6r_len, len);

	proto_tree_add_item(rthdr_tree, hf_ipv6_routing_hdr_type, tvb,
		  offset + offsetof(struct ip6_rthdr, ip6r_type), 1, FALSE);

	proto_tree_add_item(rthdr_tree, hf_ipv6_routing_hdr_left, tvb,
		  offset + offsetof(struct ip6_rthdr, ip6r_segleft), 1, FALSE);

	if (rt.ip6r_type == IPv6_RT_HEADER_SOURCE_ROUTING && len <= sizeof(buf)) {
	    struct e_in6_addr *a;
	    int n;
	    struct ip6_rthdr0 *rt0;

	    tvb_memcpy(tvb, buf, offset, len);
	    rt0 = (struct ip6_rthdr0 *)buf;

	    for (a = rt0->ip6r0_addr, n = 0;
		    a < (struct e_in6_addr *)(buf + len); a++, n++) {

	      proto_tree_add_item(rthdr_tree, hf_ipv6_routing_hdr_addr, tvb,
			      offset + offsetof(struct ip6_rthdr0, ip6r0_addr)
				     + n * sizeof(struct e_in6_addr),
			      sizeof(struct e_in6_addr), FALSE);
	      SET_ADDRESS(&pinfo->dst, AT_IPv6, 16, tvb_get_ptr(tvb,
			      offset + offsetof(struct ip6_rthdr0, ip6r0_addr)
				     + n * sizeof(struct e_in6_addr), 16));
	    }
	}
	if (rt.ip6r_type == IPv6_RT_HEADER_MobileIP) {
	  proto_tree_add_item(rthdr_tree, hf_ipv6_mipv6_home_address, tvb,
			      offset + 8, 16, FALSE);
	  SET_ADDRESS(&pinfo->dst, AT_IPv6, 16, tvb_get_ptr(tvb, offset + 8, 16));
	}
    }

    return len;
}

static int
dissect_frag6(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree,
    guint16 *offlg, guint32 *ident) {
    struct ip6_frag frag;
    int len;
    proto_item *ti;
    proto_tree *rthdr_tree;

    tvb_memcpy(tvb, (guint8 *)&frag, offset, sizeof(frag));
    len = sizeof(frag);
    frag.ip6f_offlg = g_ntohs(frag.ip6f_offlg);
    frag.ip6f_ident = g_ntohl(frag.ip6f_ident);
    *offlg = frag.ip6f_offlg;
    *ident = frag.ip6f_ident;
    if (check_col(pinfo->cinfo, COL_INFO)) {
	col_add_fstr(pinfo->cinfo, COL_INFO,
	    "IPv6 fragment (nxt=%s (0x%02x) off=%u id=0x%x)",
	    ipprotostr(frag.ip6f_nxt), frag.ip6f_nxt,
	    frag.ip6f_offlg & IP6F_OFF_MASK, frag.ip6f_ident);
    }
    if (tree) {
	   ti = proto_tree_add_text(tree, tvb, offset, len,
			   "Fragmentation Header");
	   rthdr_tree = proto_item_add_subtree(ti, ett_ipv6);

	   proto_tree_add_text(rthdr_tree, tvb,
			 offset + offsetof(struct ip6_frag, ip6f_nxt), 1,
			 "Next header: %s (0x%02x)",
			 ipprotostr(frag.ip6f_nxt), frag.ip6f_nxt);

#if 0
	   proto_tree_add_text(rthdr_tree, tvb,
			 offset + offsetof(struct ip6_frag, ip6f_reserved), 1,
			 "Reserved: %u",
			 frag.ip6f_reserved);
#endif

	   proto_tree_add_item(rthdr_tree, hf_ipv6_frag_offset, tvb,
		    offset + offsetof(struct ip6_frag, ip6f_offlg), 2, FALSE);

	   proto_tree_add_item(rthdr_tree, hf_ipv6_frag_more, tvb,
		    offset + offsetof(struct ip6_frag, ip6f_offlg), 2, FALSE);

	   proto_tree_add_item(rthdr_tree, hf_ipv6_frag_id, tvb,
		    offset + offsetof(struct ip6_frag, ip6f_ident), 4, FALSE);
    }
    return len;
}

static int
dissect_mipv6_hoa(tvbuff_t *tvb, proto_tree *dstopt_tree, int offset, packet_info *pinfo)
{
    int len = 0;

    proto_tree_add_uint_format(dstopt_tree, hf_ipv6_mipv6_type, tvb,
	offset + len, 1,
	tvb_get_guint8(tvb, offset + len),
	"Option Type: %u (0x%02x) - Home Address Option",
	tvb_get_guint8(tvb, offset + len),
	tvb_get_guint8(tvb, offset + len));
    len += 1;

    proto_tree_add_uint(dstopt_tree, hf_ipv6_mipv6_length, tvb, offset + len,
	1, tvb_get_guint8(tvb, offset + len));
    len += 1;

    proto_tree_add_ipv6(dstopt_tree, hf_ipv6_mipv6_home_address, tvb,
	offset + len, 16, tvb_get_ptr(tvb, offset + len, 16));
    SET_ADDRESS(&pinfo->src, AT_IPv6, 16, tvb_get_ptr(tvb, offset + len, 16));
    len += 16;
    return len;
}

static const value_string rtalertvals[] = {
    { IP6OPT_RTALERT_MLD, "MLD" },
    { IP6OPT_RTALERT_RSVP, "RSVP" },
    { 0, NULL }
};

/* Like "dissect_ip_tcp_options()", but assumes the length of an option
   *doesn't* include the type and length bytes. */
void
dissect_ipv6_options(tvbuff_t *tvb, int offset, guint length,
			const ip_tcp_opt *opttab, int nopts, int eol,
			packet_info *pinfo, proto_tree *opt_tree)
{
  guchar            opt;
  const ip_tcp_opt *optp;
  opt_len_type      len_type;
  unsigned int      optlen;
  const char       *name;
  char              name_str[7+1+1+2+2+1+1];	/* "Unknown (0x%02x)" */
  void            (*dissect)(const struct ip_tcp_opt *, tvbuff_t *,
				int, guint, packet_info *, proto_tree *);
  guint             len;

  while (length > 0) {
    opt = tvb_get_guint8(tvb, offset);
    for (optp = &opttab[0]; optp < &opttab[nopts]; optp++) {
      if (optp->optcode == opt)
        break;
    }
    if (optp == &opttab[nopts]) {
      /* We assume that the only NO_LENGTH options are Pad1 options,
         so that we can treat unknown options as VARIABLE_LENGTH with a
	 minimum of 0, and at least be able to move on to the next option
	 by using the length in the option. */
      optp = NULL;	/* indicate that we don't know this option */
      len_type = VARIABLE_LENGTH;
      optlen = 0;
      g_snprintf(name_str, sizeof name_str, "Unknown (0x%02x)", opt);
      name = name_str;
      dissect = NULL;
    } else {
      len_type = optp->len_type;
      optlen = optp->optlen;
      name = optp->name;
      dissect = optp->dissect;
    }
    --length;      /* account for type byte */
    if (len_type != NO_LENGTH) {
      /* Option has a length. Is it in the packet? */
      if (length == 0) {
        /* Bogus - packet must at least include option code byte and
           length byte! */
        proto_tree_add_text(opt_tree, tvb, offset,      1,
              "%s (length byte past end of options)", name);
        return;
      }
      len = tvb_get_guint8(tvb, offset + 1);  /* total including type, len */
      --length;    /* account for length byte */
      if (len > length) {
        /* Bogus - option goes past the end of the header. */
        proto_tree_add_text(opt_tree, tvb, offset,      length,
              "%s (option length = %u byte%s says option goes past end of options)",
	      name, len, plurality(len, "", "s"));
        return;
      } else if (len_type == FIXED_LENGTH && len != optlen) {
        /* Bogus - option length isn't what it's supposed to be for this
           option. */
        proto_tree_add_text(opt_tree, tvb, offset,      2 + len,
              "%s (with option length = %u byte%s; should be %u)", name,
              len, plurality(len, "", "s"), optlen);
        return;
      } else if (len_type == VARIABLE_LENGTH && len < optlen) {
        /* Bogus - option length is less than what it's supposed to be for
           this option. */
        proto_tree_add_text(opt_tree, tvb, offset,      2 + len,
              "%s (with option length = %u byte%s; should be >= %u)", name,
              len, plurality(len, "", "s"), optlen);
        return;
      } else {
        if (optp == NULL) {
          proto_tree_add_text(opt_tree, tvb, offset,    2 + len, "%s (%u byte%s)",
				name, len, plurality(len, "", "s"));
        } else {
          if (dissect != NULL) {
            /* Option has a dissector. */
            (*dissect)(optp, tvb, offset,          2 + len, pinfo, opt_tree);
          } else {
            /* Option has no data, hence no dissector. */
            proto_tree_add_text(opt_tree, tvb, offset,  2 + len, "%s", name);
          }
        }
        offset += 2 + len;
      }
      length -= len;
    } else {
      proto_tree_add_text(opt_tree, tvb, offset,      1, "%s", name);
      offset += 1;
    }
    if (opt == eol)
      break;
  }
}

static int
dissect_unknown_option(tvbuff_t *tvb, int offset, proto_tree *tree)
{
    struct ip6_ext ext;
    int len;
    proto_tree *unkopt_tree;
    proto_item *ti;

    tvb_memcpy(tvb, (guint8 *)&ext, offset, sizeof(ext));
    len = (ext.ip6e_len + 1) << 3;

    if (tree) {
	/* !!! specify length */
	ti = proto_tree_add_item(tree, hf_ipv6_unk_hdr, tvb, offset, len, FALSE);

	unkopt_tree = proto_item_add_subtree(ti, ett_ipv6);

	proto_tree_add_text(unkopt_tree, tvb,
	    offset + offsetof(struct ip6_ext, ip6e_nxt), 1,
	    "Next header: %s (0x%02x)", ipprotostr(ext.ip6e_nxt), ext.ip6e_nxt);

	proto_tree_add_text(unkopt_tree, tvb,
	    offset + offsetof(struct ip6_ext, ip6e_len), 1,
	    "Length: %u (%d bytes)", ext.ip6e_len, len);
    }
    return len;
}

static int
dissect_opts(tvbuff_t *tvb, int offset, proto_tree *tree, packet_info * pinfo, const int hf_option_item)
{
    struct ip6_ext ext;
    int len;
    proto_tree *dstopt_tree;
    proto_item *ti;
    gint p;
    guint8 tmp;
    int mip_offset = 0, delta = 0;

    tvb_memcpy(tvb, (guint8 *)&ext, offset, sizeof(ext));
    len = (ext.ip6e_len + 1) << 3;

    if (tree) {
	/* !!! specify length */
	ti = proto_tree_add_item(tree, hf_option_item, tvb, offset, len, FALSE);

	dstopt_tree = proto_item_add_subtree(ti, ett_ipv6);

	proto_tree_add_text(dstopt_tree, tvb,
	    offset + offsetof(struct ip6_ext, ip6e_nxt), 1,
	    "Next header: %s (0x%02x)", ipprotostr(ext.ip6e_nxt), ext.ip6e_nxt);

	proto_tree_add_text(dstopt_tree, tvb,
	    offset + offsetof(struct ip6_ext, ip6e_len), 1,
	    "Length: %u (%d bytes)", ext.ip6e_len, len);

	mip_offset = offset;
	mip_offset += 2;

	p = offset + 2;

	while (p < offset + len) {
	    switch (tvb_get_guint8(tvb, p)) {
	    case IP6OPT_PAD1:
		proto_tree_add_item(dstopt_tree, hf_ipv6_opt_pad1, tvb, p, 1, FALSE);
		p++;
		mip_offset++;
		break;
	    case IP6OPT_PADN:
		/* RFC 2460 states :
		 * "The PadN option is used to insert two or more octets of
		 * padding into the Options area of a header.  For N octets of
		 * padding, the Opt Data Len field contains the value N-2, and
		 * the Option Data consists of N-2 zero-valued octets."
		 */
		tmp = tvb_get_guint8(tvb, p + 1);
		proto_tree_add_uint_format(dstopt_tree, hf_ipv6_opt_padn, tvb,
					    p, tmp + 2, tmp + 2,
					    "PadN: %u bytes", tmp + 2);
		p += tmp + 2;
		mip_offset += tvb_get_guint8(tvb, mip_offset + 1) + 2;
		break;
	    case IP6OPT_JUMBO:
		tmp = tvb_get_guint8(tvb, p + 1);
		if (tmp == 4) {
		    proto_tree_add_text(dstopt_tree, tvb, p, tmp + 2,
			"Jumbo payload: %u (%u bytes)",
			tvb_get_ntohl(tvb, p + 2), tmp + 2);
		} else {
		    ti = proto_tree_add_text(dstopt_tree, tvb, p, tmp + 2,
			"Jumbo payload: Invalid length (%u bytes)",  tmp);
		    expert_add_info_format(pinfo, ti, PI_MALFORMED, PI_ERROR,
			"Jumbo payload: Invalid length (%u bytes)", tmp);
		}
		p += tmp + 2;
		mip_offset += tvb_get_guint8(tvb, mip_offset+1)+2;
		break;
	    case IP6OPT_RTALERT:
	      {
		tmp = tvb_get_guint8(tvb, p + 1);
		if (tmp == 2) {
		    proto_tree_add_text(dstopt_tree, tvb, p , tmp + 2,
			    "Router alert: %s (%u bytes)",
			    val_to_str(tvb_get_ntohs(tvb, p + 2),
					rtalertvals, "Unknown"),
			    tmp + 2);
		} else {
		    ti = proto_tree_add_text(dstopt_tree, tvb, p , tmp + 2,
			    "Router alert: Invalid Length (%u bytes)",
			    tmp + 2);
		    expert_add_info_format(pinfo, ti, PI_MALFORMED, PI_ERROR,
			    "Router alert: Invalid Length (%u bytes)",
			    tmp + 2);
		}

		p += tmp + 2;
		mip_offset += tvb_get_guint8(tvb, mip_offset + 1) + 2;
		break;
	      }
	    case IP6OPT_HOME_ADDRESS:
		delta = dissect_mipv6_hoa(tvb, dstopt_tree, mip_offset, pinfo);
		p += delta;
		mip_offset += delta;
		break;
	    default:
		p = offset + len;
		break;
	    }
	}

	/* decode... */
    }
    return len;
}

static int
dissect_hopopts(tvbuff_t *tvb, int offset, proto_tree *tree, packet_info * pinfo)
{
    return dissect_opts(tvb, offset, tree, pinfo, hf_ipv6_hop_opt);
}

static int
dissect_dstopts(tvbuff_t *tvb, int offset, proto_tree *tree, packet_info * pinfo)
{
    return dissect_opts(tvb, offset, tree, pinfo, hf_ipv6_dst_opt);
}

/* START SHIM6 PART */
static guint16 shim_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_shim_hex(tvbuff_t *tvb, int offset, int len, const char *itemname, guint8 bitmask, proto_tree *tree)
{
    proto_item *ti;
    int count;
    gint p;

    p = offset;

    ti = proto_tree_add_text(tree, tvb, offset, len, "%s", itemname);

    proto_item_append_text(ti, " 0x%02x", tvb_get_guint8(tvb, p) & bitmask);
    for (count=1; count<len; count++)
      proto_item_append_text(ti, "%02x", tvb_get_guint8(tvb, p+count));

    return len;
}

static const value_string shimoptvals[] = {
    { SHIM6_OPT_RESPVAL,  "Responder Validator Option" },
    { SHIM6_OPT_LOCLIST,  "Locator List Option" },
    { SHIM6_OPT_LOCPREF,  "Locator Preferences Option" },
    { SHIM6_OPT_CGAPDM,	  "CGA Parameter Data Structure Option" },
    { SHIM6_OPT_CGASIG,	  "CGA Signature Option" },
    { SHIM6_OPT_ULIDPAIR, "ULID Pair Option" },
    { SHIM6_OPT_FII,	  "Forked Instance Identifier Option" },
    { 0, NULL }
};

static const value_string shimverifmethods[] = {
    { SHIM6_VERIF_HBA, "HBA" },
    { SHIM6_VERIF_CGA, "CGA" },
    { 0, NULL }
};

static const value_string shimflags[] _U_ = {
    { SHIM6_FLAG_BROKEN,    "BROKEN" },
    { SHIM6_FLAG_TEMPORARY, "TEMPORARY" },
    { 0, NULL }
};

static const value_string shimreapstates[] = {
    { SHIM6_REAP_OPERATIONAL, "Operational" },
    { SHIM6_REAP_EXPLORING,   "Exploring" },
    { SHIM6_REAP_INBOUNDOK,   "InboundOK" },
    { 0, NULL }
};

static const value_string shim6_protocol[] = {
  { 0, "SHIM6" },
  { 1, "HIP" },
  { 0, NULL }
};

static const value_string dscp_vals[] = {
		  { IPDSFIELD_DSCP_DEFAULT, "Default"               },
		  { IPDSFIELD_DSCP_CS1,     "Class Selector 1"      },
		  { IPDSFIELD_DSCP_CS2,     "Class Selector 2"      },
		  { IPDSFIELD_DSCP_CS3,     "Class Selector 3"      },
		  { IPDSFIELD_DSCP_CS4,     "Class Selector 4"      },
		  { IPDSFIELD_DSCP_CS5,     "Class Selector 5"      },
		  { IPDSFIELD_DSCP_CS6,     "Class Selector 6"      },
		  { IPDSFIELD_DSCP_CS7,     "Class Selector 7"      },
		  { IPDSFIELD_DSCP_AF11,    "Assured Forwarding 11" },
		  { IPDSFIELD_DSCP_AF12,    "Assured Forwarding 12" },
		  { IPDSFIELD_DSCP_AF13,    "Assured Forwarding 13" },
		  { IPDSFIELD_DSCP_AF21,    "Assured Forwarding 21" },
		  { IPDSFIELD_DSCP_AF22,    "Assured Forwarding 22" },
		  { IPDSFIELD_DSCP_AF23,    "Assured Forwarding 23" },
		  { IPDSFIELD_DSCP_AF31,    "Assured Forwarding 31" },
		  { IPDSFIELD_DSCP_AF32,    "Assured Forwarding 32" },
		  { IPDSFIELD_DSCP_AF33,    "Assured Forwarding 33" },
		  { IPDSFIELD_DSCP_AF41,    "Assured Forwarding 41" },
		  { IPDSFIELD_DSCP_AF42,    "Assured Forwarding 42" },
		  { IPDSFIELD_DSCP_AF43,    "Assured Forwarding 43" },
		  { IPDSFIELD_DSCP_EF,      "Expedited Forwarding"  },
		  { 0,                      NULL                    } };

static void
dissect_shim6_opt_loclist(proto_tree * opt_tree, tvbuff_t * tvb, gint *offset)
{
  proto_item * it;
  proto_tree * subtree;
  guint count;
  guint optlen;
  int p = *offset;

  proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_loclist, tvb, p, 4, FALSE);
  p += 4;

  optlen = tvb_get_guint8(tvb, p);
  proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_locnum, tvb, p, 1, FALSE);
  p++;

  /* Verification Methods */
  it = proto_tree_add_text(opt_tree, tvb, p, optlen,
			    "Locator Verification Methods");
  subtree = proto_item_add_subtree(it, ett_ipv6_shim6_verif_methods);

  for (count=0; count < optlen; count++)
    proto_tree_add_item(subtree, hf_ipv6_shim6_opt_loc_verif_methods, tvb,
			    p+count, 1, FALSE);
  p += optlen;

  /* Padding, included in length field */
  if ((7 - optlen % 8) > 0) {
      proto_tree_add_text(opt_tree, tvb, p, (7 - optlen % 8), "Padding");
      p += (7 - optlen % 8);
  }

  /* Locators */
  it = proto_tree_add_text(opt_tree, tvb, p, 16 * optlen, "Locators");
  subtree = proto_item_add_subtree(it, ett_ipv6_shim6_locators);

  for (count=0; count < optlen; count++) {
      proto_tree_add_item(subtree, hf_ipv6_shim6_locator, tvb, p, 16, FALSE);
      p += 16;
  }
  *offset = p;
}

static void
dissect_shim6_opt_loc_pref(proto_tree * opt_tree, tvbuff_t * tvb, gint *offset, gint len, packet_info *pinfo)
{
  proto_tree * subtree;
  proto_item * it;

  gint p;
  gint optlen;
  gint count;

  p = *offset;

  proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_loclist, tvb, p, 4, FALSE);
  p += 4;

  optlen = tvb_get_guint8(tvb, p);
  proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_elemlen, tvb, p, 1, FALSE);

  if (optlen < 1 || optlen > 3) {
    it = proto_tree_add_text(opt_tree, tvb, p, 1,
      "Invalid element length: %u",  optlen);
    expert_add_info_format(pinfo, it, PI_MALFORMED, PI_ERROR,
      "Invalid element length: %u", optlen);
    return;
  }

  p++;

  /* Locator Preferences */
  count = 1;
  while (p < len) {
    it = proto_tree_add_text(opt_tree, tvb, p, optlen, "Locator Preferences %u", count);
    subtree = proto_item_add_subtree(it, ett_ipv6_shim6_loc_pref);

    /* Flags */
    if (optlen >= 1)
      proto_tree_add_item(subtree, hf_ipv6_shim6_loc_flag, tvb, p, 1, FALSE);
    /* Priority */
    if (optlen >= 2)
      proto_tree_add_item(subtree, hf_ipv6_shim6_loc_prio, tvb, p+1, 1, FALSE);
    /* Weight */
    if (optlen >= 3)
      proto_tree_add_item(subtree, hf_ipv6_shim6_loc_weight, tvb, p+2, 1, FALSE);
    /*
     * Shim6 Draft 08 doesn't specify the format when the Element length is
     * more than three, except that any such formats MUST be defined so that
     * the first three octets are the same as in the above case, that is, a
     * of a 1 octet flags field followed by a 1 octet priority field, and a
     * 1 octet weight field.
     */
    p += optlen;
    count++;
  }
  *offset = p;
}


static int
dissect_shimopts(tvbuff_t *tvb, int offset, proto_tree *tree, packet_info *pinfo)
{
    int len, total_len;
    gint p;
    gint padding;
    proto_tree *opt_tree;
    proto_item *ti;
    guint8 tmp[2];
    const gchar *ctype;


    p = offset;

    tmp[0] = tvb_get_guint8(tvb, p++);
    tmp[1] = tvb_get_guint8(tvb, p++);
    p += 2;

    len = tvb_get_ntohs(tvb, offset+2);
    padding = 7 - ((len + 3) % 8);
    total_len = 4 + len + padding;

    if (tree)
    {
	/* Option Type */
	ctype = val_to_str( (tvb_get_ntohs(tvb, offset) & SHIM6_BITMASK_OPT_TYPE) >> 1, shimoptvals, "Unknown Option Type");
	ti = proto_tree_add_text(tree, tvb, offset, total_len, "%s", ctype);
	opt_tree = proto_item_add_subtree(ti, ett_ipv6_shim6_option);

	proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_type, tvb, offset, 2, FALSE);

	/* Critical */
	proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_critical, tvb, offset+1, 1, FALSE);

	/* Content Length */
	proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_len, tvb, offset + 2, 2, FALSE);
	ti = proto_tree_add_uint_format(opt_tree, hf_ipv6_shim6_opt_total_len, tvb, offset+2, 2,
	    total_len, "Total Length: %u", total_len);
	PROTO_ITEM_SET_GENERATED(ti);

	/* Option Type Specific */
	switch (tvb_get_ntohs(tvb, offset) >> 1)
	{
	    case SHIM6_OPT_RESPVAL:
		p += dissect_shim_hex(tvb, p, len, "Validator:", 0xff, opt_tree);
		if (total_len-(len+4) > 0)
		    proto_tree_add_text(opt_tree, tvb, p, total_len-(len+4), "Padding");
		break;
	    case SHIM6_OPT_LOCLIST:
		dissect_shim6_opt_loclist(opt_tree, tvb, &p);
		break;
	    case SHIM6_OPT_LOCPREF:
		dissect_shim6_opt_loc_pref(opt_tree, tvb, &p, offset+len+4, pinfo);
		if (total_len-(len+4) > 0)
		  proto_tree_add_text(opt_tree, tvb, p, total_len-(len+4), "Padding");
		break;
	    case SHIM6_OPT_CGAPDM:
		p += dissect_shim_hex(tvb, p, len, "CGA Parameter Data Structure:", 0xff, opt_tree);
		if (total_len-(len+4) > 0)
		    proto_tree_add_text(opt_tree, tvb, p, total_len-(len+4), "Padding");
		break;
	    case SHIM6_OPT_CGASIG:
		p += dissect_shim_hex(tvb, p, len, "CGA Signature:", 0xff, opt_tree);
		if (total_len-(len+4) > 0)
		    proto_tree_add_text(opt_tree, tvb, p, total_len-(len+4), "Padding");
		break;
	    case SHIM6_OPT_ULIDPAIR:
		proto_tree_add_text(opt_tree, tvb, p, 4, "Reserved");
		p += 4;
		proto_tree_add_item(opt_tree, hf_ipv6_shim6_sulid, tvb, p, 16, FALSE);
		p += 16;
		proto_tree_add_item(opt_tree, hf_ipv6_shim6_rulid, tvb, p, 16, FALSE);
		p += 16;
		break;
	    case SHIM6_OPT_FII:
		proto_tree_add_item(opt_tree, hf_ipv6_shim6_opt_fii, tvb, p, 4, FALSE);
		p += 4;
		break;
	    default:
		break;
	}
    }
    return total_len;
}

static void
dissect_shim6_ct(proto_tree * shim_tree, gint hf_item, tvbuff_t * tvb, gint offset, const guchar * label)
{
  guint8 tmp[6];
  guchar * ct_str;

  tmp[0] = tvb_get_guint8(tvb, offset++);
  tmp[1] = tvb_get_guint8(tvb, offset++);
  tmp[2] = tvb_get_guint8(tvb, offset++);
  tmp[3] = tvb_get_guint8(tvb, offset++);
  tmp[4] = tvb_get_guint8(tvb, offset++);
  tmp[5] = tvb_get_guint8(tvb, offset++);

  ct_str = ep_strdup_printf("%s: %02X %02X %02X %02X %02X %02X", label,
			      tmp[0] & SHIM6_BITMASK_CT, tmp[1], tmp[2],
			      tmp[3], tmp[4], tmp[5]
			    );
  proto_tree_add_none_format(shim_tree, hf_item, tvb, offset - 6, 6, "%s", ct_str);
}

static void
dissect_shim6_probes(proto_tree * shim_tree, tvbuff_t * tvb, gint offset,
                     const guchar * label, guint nbr_probe,
		     gboolean probes_rcvd)
{
  proto_tree * probes_tree;
  proto_tree * probe_tree;
  proto_item * it;
  gint ett_probes;
  gint ett_probe;
  guint count;

  if (probes_rcvd) {
    ett_probes = ett_ipv6_shim6_probes_rcvd;
    ett_probe = ett_ipv6_shim6_probe_rcvd;
  } else {
    ett_probes = ett_ipv6_shim6_probes_sent;
    ett_probe = ett_ipv6_shim6_probe_sent;
  }
  it = proto_tree_add_text(shim_tree, tvb, offset, 40 * nbr_probe, "%s", label);
  probes_tree = proto_item_add_subtree(it, ett_probes);

  for (count=0; count < nbr_probe; count++) {
    it = proto_tree_add_text(probes_tree, tvb, offset, 40, "Probe %u", count+1);
    probe_tree = proto_item_add_subtree(it, ett_probe);

    proto_tree_add_item(probe_tree, hf_ipv6_shim6_psrc, tvb, offset, 16, FALSE);
    offset += 16;
    proto_tree_add_item(probe_tree, hf_ipv6_shim6_pdst, tvb, offset, 16, FALSE);
    offset += 16;

    proto_tree_add_item(probe_tree, hf_ipv6_shim6_pnonce, tvb, offset, 4, FALSE);
    offset += 4;

    proto_tree_add_item(probe_tree, hf_ipv6_shim6_pdata, tvb, offset, 4, FALSE);
    offset += 4;
  }
}

/* Dissect SHIM6 data: control messages */
static int
dissect_shimctrl(tvbuff_t *tvb, gint offset, guint type, proto_tree *shim_tree)
{
  gint p;
  guint8 tmp;
  const gchar *sta;
  guint probes_sent;
  guint probes_rcvd;

    p = offset;

    switch (type)
    {
	case SHIM6_TYPE_I1:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Initiator Context Tag");
	    p += 6;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_inonce, tvb, p, 4, FALSE);
	    p += 4;
	    break;
	case SHIM6_TYPE_R1:
	    proto_tree_add_text(shim_tree, tvb, p, 2, "Reserved2");
	    p += 2;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_inonce, tvb, p, 4, FALSE);
	    p += 4;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_rnonce, tvb, p, 4, FALSE);
	    p += 4;
	    break;
	case SHIM6_TYPE_I2:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Initiator Context Tag");
	    p += 6;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_inonce, tvb, p, 4, FALSE);
	    p += 4;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_rnonce, tvb, p, 4, FALSE);
	    p += 4;
	    proto_tree_add_text(shim_tree, tvb, p, 4, "Reserved2");
	    p += 4;
	    break;
	case SHIM6_TYPE_R2:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Responder Context Tag");
	    p += 6;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_inonce, tvb, p, 4, FALSE);
	    p += 4;
	    break;
	case SHIM6_TYPE_R1BIS:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Packet Context Tag");
	    p += 6;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_rnonce, tvb, p, 4, FALSE);
	    p += 4;
	    break;
	case SHIM6_TYPE_I2BIS:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Initiator Context Tag");
	    p += 6;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_inonce, tvb, p, 4, FALSE);
	    p += 4;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_rnonce, tvb, p, 4, FALSE);
	    p += 4;
	    proto_tree_add_text(shim_tree, tvb, p, 6, "Reserved2");
	    p += 6;
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Initiator Context Tag");
	    p += 6;
	    break;
	case SHIM6_TYPE_UPD_REQ:
	case SHIM6_TYPE_UPD_ACK:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Receiver Context Tag");
	    p += 6;
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_rnonce, tvb, p, 4, FALSE);
	    p += 4;
	    break;
	case SHIM6_TYPE_KEEPALIVE:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Receiver Context Tag");
	    p += 6;
	    proto_tree_add_text(shim_tree, tvb, p, 4, "Reserved2");
	    p += 4;
	    break;
	case SHIM6_TYPE_PROBE:
	    dissect_shim6_ct(shim_tree, hf_ipv6_shim6_ct, tvb, p, "Receiver Context Tag");
	    p += 6;

	    tmp = tvb_get_guint8(tvb, p);
	    probes_sent = tmp & SHIM6_BITMASK_PSENT;
	    probes_rcvd = (tmp & SHIM6_BITMASK_PRECVD) >> 4;

	    proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_psent, tvb,
					p, 1, probes_sent,
					"Probes Sent: %u", probes_sent);
	    proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_precvd, tvb,
					p, 1, probes_rcvd,
					"Probes Received: %u", probes_rcvd);
	    p++;

	    sta = val_to_str((tvb_get_guint8(tvb, p) & SHIM6_BITMASK_STA) >> 6,
					shimreapstates, "Unknown REAP State");
	    proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_reap, tvb,
	    	p, 1, (tvb_get_guint8(tvb, p) & SHIM6_BITMASK_STA) >> 6,
		"REAP State: %s", sta);

	    proto_tree_add_text(shim_tree, tvb, p, 3, "Reserved2");
	    p += 3;

	    /* Probes Sent */
	    if (probes_sent) {
	      dissect_shim6_probes(shim_tree, tvb, p, "Probes Sent",
							  probes_sent, FALSE);
	      p += 40 * probes_sent;
	    }

	   /* Probes Received */
	    if (probes_rcvd) {
	      dissect_shim6_probes(shim_tree, tvb, p, "Probes Received",
							  probes_rcvd, TRUE);
	      p += 40 * probes_rcvd;
	    }
	   break;
	default:
	   break;
    }
    return p-offset;
}

/* Dissect SHIM6 data: payload, common part, options */
static const value_string shimctrlvals[] = {
    { SHIM6_TYPE_I1,	    "I1" },
    { SHIM6_TYPE_R1,	    "R1" },
    { SHIM6_TYPE_I2,	    "I2" },
    { SHIM6_TYPE_R2,	    "R2" },
    { SHIM6_TYPE_R1BIS,	    "R1bis" },
    { SHIM6_TYPE_I2BIS,	    "I2bis" },
    { SHIM6_TYPE_UPD_REQ,   "Update Request" },
    { SHIM6_TYPE_UPD_ACK,   "Update Acknowledgement" },
    { SHIM6_TYPE_KEEPALIVE, "Keepalive" },
    { SHIM6_TYPE_PROBE,	    "Probe" },
    { 0, NULL }
};

static void ipv6_shim6_checkum_additional_info(tvbuff_t * tvb, packet_info * pinfo,
    proto_item * it_cksum, int offset, gboolean is_cksum_correct)
{
	proto_tree * checksum_tree;
	proto_item * item;

	checksum_tree = proto_item_add_subtree(it_cksum, ett_ipv6_shim6_cksum);
        item = proto_tree_add_boolean(checksum_tree, hf_ipv6_shim6_checksum_good, tvb,
	   offset, 2, is_cksum_correct);
        PROTO_ITEM_SET_GENERATED(item);
        item = proto_tree_add_boolean(checksum_tree, hf_ipv6_shim6_checksum_bad, tvb,
	   offset, 2, !is_cksum_correct);
        PROTO_ITEM_SET_GENERATED(item);
	if (!is_cksum_correct) {
	  expert_add_info_format(pinfo, item, PI_CHECKSUM, PI_ERROR, "Bad checksum");
	  col_append_str(pinfo->cinfo, COL_INFO, " [Shim6 CHECKSUM INCORRECT]");
	}
}

static int
dissect_shim6(tvbuff_t *tvb, int offset, proto_tree *tree, packet_info * pinfo)
{
    struct ip6_shim shim;
    int len;
    gint p;
    proto_tree *shim_tree;
    proto_item *ti;
    guint8 tmp[5];

    tvb_memcpy(tvb, (guint8 *)&shim, offset, sizeof(shim));
    len = (shim.ip6s_len + 1) << 3;

    if (tree)
    {
    	ti = proto_tree_add_item(tree, hf_ipv6_shim6, tvb, offset, len, FALSE);
	shim_tree = proto_item_add_subtree(ti, ett_ipv6_shim6);

	/* Next Header */
	proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_nxt, tvb,
	    offset + offsetof(struct ip6_shim, ip6s_nxt), 1, shim.ip6s_nxt,
	    "Next header: %s (0x%02x)", ipprotostr(shim.ip6s_nxt), shim.ip6s_nxt);

	/* Header Extension Length */
	proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_len, tvb,
	    offset + offsetof(struct ip6_shim, ip6s_len), 1, shim.ip6s_len,
	    "Header Ext Length: %u (%d bytes)", shim.ip6s_len, len);

	/* P Field */
	proto_tree_add_item(shim_tree, hf_ipv6_shim6_p, tvb,
			      offset + offsetof(struct ip6_shim, ip6s_p), 1, FALSE);

	/* skip the first 2 bytes (nxt hdr, hdr ext len, p+7bits) */
	p = offset + 3;

	if (shim.ip6s_p & SHIM6_BITMASK_P)
	{
	    tmp[0] = tvb_get_guint8(tvb, p++);
	    tmp[1] = tvb_get_guint8(tvb, p++);
	    tmp[2] = tvb_get_guint8(tvb, p++);
	    tmp[3] = tvb_get_guint8(tvb, p++);
	    tmp[4] = tvb_get_guint8(tvb, p++);

	    /* Payload Extension Header */
	    proto_tree_add_none_format(shim_tree, hf_ipv6_shim6_ct, tvb,
		offset + offsetof(struct ip6_shim, ip6s_p), 6,
		"Receiver Context Tag: %02x %02x %02x %02x %02x %02x",
		shim.ip6s_p & SHIM6_BITMASK_CT, tmp[0], tmp[1], tmp[2], tmp[3], tmp[4]);
	}
	else
        {
	    /* Control Message */
	    guint16 csum;
	    int advance;

	    /* Message Type */
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_type, tvb,
				offset + offsetof(struct ip6_shim, ip6s_p), 1,
				FALSE
				);

	    /* Protocol bit (Must be zero for SHIM6) */
	    proto_tree_add_item(shim_tree, hf_ipv6_shim6_proto, tvb, p, 1, FALSE);
	    p++;

	    /* Checksum */
	    csum = shim_checksum(tvb_get_ptr(tvb, offset, len), len);

	    if (csum == 0) {
		ti = proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_checksum, tvb, p, 2,
		    tvb_get_ntohs(tvb, p), "Checksum: 0x%04x [correct]", tvb_get_ntohs(tvb, p));
		ipv6_shim6_checkum_additional_info(tvb, pinfo, ti, p, TRUE);
	    } else {
		ti = proto_tree_add_uint_format(shim_tree, hf_ipv6_shim6_checksum, tvb, p, 2,
		    tvb_get_ntohs(tvb, p), "Checksum: 0x%04x [incorrect: should be 0x%04x]",
		    tvb_get_ntohs(tvb, p), in_cksum_shouldbe(tvb_get_ntohs(tvb, p), csum));
		ipv6_shim6_checkum_additional_info(tvb, pinfo, ti, p, FALSE);
	    }
	    p += 2;

	    /* Type specific data */
	    advance = dissect_shimctrl(tvb, p, shim.ip6s_p & SHIM6_BITMASK_TYPE, shim_tree);
	    p += advance;

	    /* Options */
	    while (p < offset+len) {
	      p += dissect_shimopts(tvb, p, shim_tree, pinfo);
	    }
	}
    }
    return len;
}

/* END SHIM6 PART */

static void
dissect_ipv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
  proto_tree *ipv6_tree = NULL;
  proto_item *ti;
  guint8 nxt;
  guint8 stype=0;
  int advance;
  int poffset;
  guint16 plen;
  gboolean hopopts, routing, frag, ah, shim6, dstopts;
  guint16 offlg;
  guint32 ident;
  int offset;
  fragment_data *ipfd_head;
  tvbuff_t   *next_tvb;
  gboolean update_col_info = TRUE;
  gboolean save_fragmented = FALSE;
  const char *sep = "IPv6 ";

  struct ip6_hdr ipv6;

  col_set_str(pinfo->cinfo, COL_PROTOCOL, "IPv6");
  col_clear(pinfo->cinfo, COL_INFO);

  offset = 0;
  tvb_memcpy(tvb, (guint8 *)&ipv6, offset, sizeof(ipv6));

  /* Get extension header and payload length */
  plen = g_ntohs(ipv6.ip6_plen);

  /* Adjust the length of this tvbuff to include only the IPv6 datagram. */
  set_actual_length(tvb, plen + sizeof (struct ip6_hdr));

  SET_ADDRESS(&pinfo->net_src, AT_IPv6, 16, tvb_get_ptr(tvb, offset + IP6H_SRC, 16));
  SET_ADDRESS(&pinfo->src, AT_IPv6, 16, tvb_get_ptr(tvb, offset + IP6H_SRC, 16));
  SET_ADDRESS(&pinfo->net_dst, AT_IPv6, 16, tvb_get_ptr(tvb, offset + IP6H_DST, 16));
  SET_ADDRESS(&pinfo->dst, AT_IPv6, 16, tvb_get_ptr(tvb, offset + IP6H_DST, 16));

  if (tree) {
    proto_tree* pt;
    proto_item* pi;
    proto_tree *ipv6_tc_tree;
    proto_item *ipv6_tc;

    /* !!! specify length */
    ti = proto_tree_add_item(tree, proto_ipv6, tvb, offset, 40, FALSE);
    ipv6_tree = proto_item_add_subtree(ti, ett_ipv6);

    /* !!! warning: (4-bit) version, (6-bit) DSCP, (1-bit) ECN-ECT, (1-bit) ECN-CE and (20-bit) Flow */
    pi = proto_tree_add_item(ipv6_tree, hf_ipv6_version, tvb,
 			offset + offsetof(struct ip6_hdr, ip6_vfc), 1, FALSE);
	pt = proto_item_add_subtree(pi,ett_ipv6_version);
    pi = proto_tree_add_item(pt, hf_ip_version, tvb,
						offset + offsetof(struct ip6_hdr, ip6_vfc), 1, FALSE);
	PROTO_ITEM_SET_GENERATED(pi);

    ipv6_tc = proto_tree_add_item(ipv6_tree, hf_ipv6_class, tvb,
			offset + offsetof(struct ip6_hdr, ip6_flow), 4, FALSE);

    ipv6_tc_tree = proto_item_add_subtree(ipv6_tc, ett_ipv6_traffic_class);

    proto_tree_add_item(ipv6_tc_tree, hf_ipv6_traffic_class_dscp, tvb,
			offset + offsetof(struct ip6_hdr, ip6_flow), 4, FALSE);

    proto_tree_add_item(ipv6_tc_tree, hf_ipv6_traffic_class_ect, tvb,
			offset + offsetof(struct ip6_hdr, ip6_flow), 4, FALSE);

    proto_tree_add_item(ipv6_tc_tree, hf_ipv6_traffic_class_ce, tvb,
			offset + offsetof(struct ip6_hdr, ip6_flow), 4, FALSE);

    proto_tree_add_item(ipv6_tree, hf_ipv6_flow, tvb,
			offset + offsetof(struct ip6_hdr, ip6_flow), 4, FALSE);

    proto_tree_add_item(ipv6_tree, hf_ipv6_plen, tvb,
			offset + offsetof(struct ip6_hdr, ip6_plen), 2, FALSE);

    proto_tree_add_uint_format(ipv6_tree, hf_ipv6_nxt, tvb,
		offset + offsetof(struct ip6_hdr, ip6_nxt), 1,
		ipv6.ip6_nxt,
		"Next header: %s (0x%02x)",
		ipprotostr(ipv6.ip6_nxt), ipv6.ip6_nxt);

    proto_tree_add_item(ipv6_tree, hf_ipv6_hlim, tvb,
			offset + offsetof(struct ip6_hdr, ip6_hlim), 1, FALSE);

    /* Adds the different items for the source address */
    proto_tree_add_item(ipv6_tree, hf_ipv6_src, tvb,
			offset + offsetof(struct ip6_hdr, ip6_src), 16, FALSE);
    ti = proto_tree_add_ipv6(ipv6_tree, hf_ipv6_addr, tvb,
			      offset + offsetof(struct ip6_hdr, ip6_src),
			      16, (guint8 *)&ipv6.ip6_src);
    PROTO_ITEM_SET_HIDDEN(ti);
    ti = proto_tree_add_string(ipv6_tree, hf_ipv6_src_host, tvb,
			      offset + offsetof(struct ip6_hdr, ip6_src),
			      16, get_addr_name(&pinfo->src));
    PROTO_ITEM_SET_GENERATED(ti);
    PROTO_ITEM_SET_HIDDEN(ti);
    ti = proto_tree_add_string(ipv6_tree, hf_ipv6_host, tvb,
			      offset + offsetof(struct ip6_hdr, ip6_src),
			      16, get_addr_name(&pinfo->src));
    PROTO_ITEM_SET_GENERATED(ti);
    PROTO_ITEM_SET_HIDDEN(ti);

    /* Adds different items for the destination address */
    proto_tree_add_item(ipv6_tree, hf_ipv6_dst, tvb,
			offset + offsetof(struct ip6_hdr, ip6_dst), 16, FALSE);
    ti = proto_tree_add_ipv6(ipv6_tree, hf_ipv6_addr, tvb,
			      offset + offsetof(struct ip6_hdr, ip6_dst),
			      16, (guint8 *)&ipv6.ip6_dst);
    PROTO_ITEM_SET_HIDDEN(ti);
    ti = proto_tree_add_string(ipv6_tree, hf_ipv6_dst_host, tvb,
			      offset + offsetof(struct ip6_hdr, ip6_dst),
			      16, get_addr_name(&pinfo->dst));
    PROTO_ITEM_SET_GENERATED(ti);
    PROTO_ITEM_SET_HIDDEN(ti);
    ti = proto_tree_add_string(ipv6_tree, hf_ipv6_host, tvb,
			      offset + offsetof(struct ip6_hdr, ip6_dst),
			      16, get_addr_name(&pinfo->dst));
    PROTO_ITEM_SET_GENERATED(ti);
    PROTO_ITEM_SET_HIDDEN(ti);
  }

  /* start of the new header (could be a extension header) */
  poffset = offset + offsetof(struct ip6_hdr, ip6_nxt);
  nxt = tvb_get_guint8(tvb, poffset);
  offset += sizeof(struct ip6_hdr);
  offlg = 0;
  ident = 0;

/* start out assuming this isn't fragmented, and has none of the other
   non-final headers */
  hopopts = FALSE;
  routing = FALSE;
  frag = FALSE;
  ah = FALSE;
  shim6 = FALSE;
  dstopts = FALSE;

again:
   switch (nxt) {

   case IP_PROTO_HOPOPTS:
      hopopts = TRUE;
      advance = dissect_hopopts(tvb, offset, ipv6_tree, pinfo);
      nxt = tvb_get_guint8(tvb, offset);
      poffset = offset;
      offset += advance;
      plen -= advance;
      goto again;

    case IP_PROTO_ROUTING:
      routing = TRUE;
      advance = dissect_routing6(tvb, offset, ipv6_tree, pinfo);
      nxt = tvb_get_guint8(tvb, offset);
      poffset = offset;
      offset += advance;
      plen -= advance;
      goto again;

    case IP_PROTO_FRAGMENT:  
      advance = dissect_frag6(tvb, offset, pinfo, ipv6_tree,
          &offlg, &ident);
      nxt = tvb_get_guint8(tvb, offset);
      poffset = offset;
      offset += advance;
      plen -= advance;
      frag = offlg & (IP6F_OFF_MASK | IP6F_MORE_FRAG);
      save_fragmented |= frag;
      if (ipv6_reassemble && frag && tvb_bytes_exist(tvb, offset, plen)) {
        ipfd_head = fragment_add_check(tvb, offset, pinfo, ident,
        ipv6_fragment_table,
        ipv6_reassembled_table,
          offlg & IP6F_OFF_MASK,
          plen,
          offlg & IP6F_MORE_FRAG);
        next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled IPv6",
        ipfd_head, &ipv6_frag_items, &update_col_info, ipv6_tree);
        if (next_tvb) {  /* Process post-fragment headers after reassembly... */
          offset= 0;
          offlg = 0;
          frag = FALSE;
          tvb = next_tvb;
          goto again; 
        }
      }
      if (!(offlg & IP6F_OFF_MASK)) /*...or in the first fragment */
        goto again;
      break;

    case IP_PROTO_AH:
      ah = TRUE;
      advance = dissect_ah_header(tvb_new_subset_remaining(tvb, offset),
                                  pinfo, ipv6_tree, NULL, NULL);
      nxt = tvb_get_guint8(tvb, offset);
      poffset = offset;
      offset += advance;
      plen -= advance;
      goto again;

    case IP_PROTO_SHIM6:
    case IP_PROTO_SHIM6_OLD:
      shim6 = TRUE;
      advance = dissect_shim6(tvb, offset, ipv6_tree, pinfo);
      nxt = tvb_get_guint8(tvb, offset);
      stype = tvb_get_guint8(tvb, offset+2);
      poffset = offset;
      offset += advance;
      plen -= advance;
      goto again;

    case IP_PROTO_DSTOPTS:
      dstopts = TRUE;
      advance = dissect_dstopts(tvb, offset, ipv6_tree, pinfo);
      nxt = tvb_get_guint8(tvb, offset);
      poffset = offset;
      offset += advance;
      plen -= advance;
      goto again;

    case IP_PROTO_NONE:
      break;

    default:
      /* Since we did not recognize this IPv6 option, check
       * whether it is a known protocol. If not, then it
       * is an unknown IPv6 option
       */
      if (!dissector_get_port_handle(ip_dissector_table, nxt)) {
        advance = dissect_unknown_option(tvb, offset, ipv6_tree); 
        nxt = tvb_get_guint8(tvb, offset);
        poffset = offset;
        offset += advance;
        plen -= advance;
        goto again;
      }
    }

#ifdef TEST_FINALHDR
  ti = proto_tree_add_uint(ipv6_tree, hf_ipv6_final, tvb, poffset, 1, nxt);
  PROTO_ITEM_SET_HIDDEN(ti);
#endif

  /* collect packet info */
  pinfo->ipproto = nxt;
  pinfo->iplen = sizeof(ipv6) + plen + offset;
  pinfo->iphdrlen = offset;

  if (offlg & IP6F_OFF_MASK || (ipv6_reassemble && offlg & IP6F_MORE_FRAG)) {
    /* Not the first fragment, or the first when we are reassembling and there are more. */
    /* Don't dissect it; just show this as a fragment. */
    /* COL_INFO was filled in by "dissect_frag6()" */
    call_dissector(data_handle, tvb_new_subset_remaining(tvb, offset), pinfo, tree);
    return;
  } else {
    /* First fragment, not fragmented, or already reassembled.  Dissect what we have here. */

    /* Get a tvbuff for the payload. */
    next_tvb = tvb_new_subset_remaining(tvb, offset);

    /*
     * If this is the first fragment, but not the only fragment,
     * tell the next protocol that.
     */
    if (offlg & IP6F_MORE_FRAG)
      pinfo->fragmented = TRUE;
    else
      pinfo->fragmented = FALSE;
  }


  /* do lookup with the subdissector table */
  if (!dissector_try_port(ip_dissector_table, nxt, next_tvb, pinfo, tree)) {
    /* Unknown protocol.
       Handle "no next header" specially. */
    if (nxt == IP_PROTO_NONE) {
      if (check_col(pinfo->cinfo, COL_INFO)) {
        /* If we had an Authentication Header, the AH dissector already
           put something in the Info column; leave it there. */
        if (!ah) {
          if (hopopts || routing || dstopts || shim6) {
            if (hopopts) {
              col_append_fstr(pinfo->cinfo, COL_INFO, "%shop-by-hop options",
                             sep);
              sep = ", ";
            }
            if (routing) {
              col_append_fstr(pinfo->cinfo, COL_INFO, "%srouting", sep);
              sep = ", ";
            }
            if (dstopts) {
              col_append_fstr(pinfo->cinfo, COL_INFO, "%sdestination options",
                              sep);
            }
            if (shim6) {
              if (stype & SHIM6_BITMASK_P) {
                col_append_str(pinfo->cinfo, COL_INFO, "Shim6 (Payload)");
	      }
              else {
                col_append_fstr(pinfo->cinfo, COL_INFO, "Shim6 (%s)",
                   val_to_str(stype & SHIM6_BITMASK_TYPE, shimctrlvals, "Unknown"));
              }
            }
          } else
            col_set_str(pinfo->cinfo, COL_INFO, "IPv6 no next header");
	}
      }
    } else {
      if (check_col(pinfo->cinfo, COL_INFO))
        col_add_fstr(pinfo->cinfo, COL_INFO, "%s (0x%02x)", ipprotostr(nxt),nxt);
    }
    call_dissector(data_handle, next_tvb, pinfo, tree);
  }
  pinfo->fragmented = save_fragmented;
}

void
proto_register_ipv6(void)
{
  static hf_register_info hf[] = {
    { &hf_ipv6_version,
      { "Version",		"ipv6.version",
				FT_UINT8, BASE_DEC, NULL, 0xF0, NULL, HFILL }},
    { &hf_ip_version,
      { "This field makes the filter \"ip.version == 6\" possible",		"ip.version",
				FT_UINT8, BASE_DEC, NULL, 0xF0, NULL, HFILL }},
    { &hf_ipv6_class,
      { "Traffic class",	"ipv6.class",
				FT_UINT32, BASE_HEX, NULL, 0x0FF00000, NULL, HFILL }},
    { &hf_ipv6_flow,
      { "Flowlabel",		"ipv6.flow",
				FT_UINT32, BASE_HEX, NULL, 0x000FFFFF, NULL, HFILL }},
    { &hf_ipv6_plen,
      { "Payload length",	"ipv6.plen",
				FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
    { &hf_ipv6_nxt,
      { "Next header",		"ipv6.nxt",
				FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL }},
    { &hf_ipv6_hlim,
      { "Hop limit",		"ipv6.hlim",
				FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
    { &hf_ipv6_src,
      { "Source",		"ipv6.src",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Source IPv6 Address", HFILL }},
    { &hf_ipv6_src_host,
      { "Source Host",		"ipv6.src_host",
				FT_STRING, BASE_NONE, NULL, 0x0,
				"Source IPv6 Host", HFILL }},
    { &hf_ipv6_dst,
      { "Destination",		"ipv6.dst",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Destination IPv6 Address", HFILL }},
    { &hf_ipv6_dst_host,
      { "Destination Host",	"ipv6.dst_host",
				FT_STRING, BASE_NONE, NULL, 0x0,
				"Destination IPv6 Host", HFILL }},
    { &hf_ipv6_addr,
      { "Address",		"ipv6.addr",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Source or Destination IPv6 Address", HFILL }},
    { &hf_ipv6_host,
      { "Host",			"ipv6.host",
				FT_STRING, BASE_NONE, NULL, 0x0,
				"IPv6 Host", HFILL }},

    { &hf_ipv6_opt_pad1,
      { "Pad1",			"ipv6.opt.pad1",
				FT_NONE, BASE_NONE, NULL, 0x0,
				"Pad1 Option", HFILL }},
    { &hf_ipv6_opt_padn,
      { "PadN",			"ipv6.opt.padn",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"PadN Option", HFILL }},
    { &hf_ipv6_dst_opt,
      { "Destination Option",	"ipv6.dst_opt",
				FT_NONE, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},
    { &hf_ipv6_hop_opt,
      { "Hop-by-Hop Option",	"ipv6.hop_opt",
				FT_NONE, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},
    { &hf_ipv6_unk_hdr,
      { "Unknown Extension Header",	"ipv6.unknown_hdr",
				FT_NONE, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},
    { &hf_ipv6_routing_hdr_opt,
      { "Routing Header, Type","ipv6.routing_hdr",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Routing Header Option", HFILL }},
    { &hf_ipv6_routing_hdr_type,
      { "Type",			"ipv6.routing_hdr.type",
				FT_UINT8, BASE_DEC, VALS(routing_header_type), 0x0,
				"Routeing Header Type", HFILL }},
    { &hf_ipv6_routing_hdr_left,
      { "Left Segments",	"ipv6.routing_hdr.left",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Routing Header Left Segments", HFILL }},
    { &hf_ipv6_routing_hdr_addr,
      { "Address",		"ipv6.routing_hdr.addr",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Routing Header Address", HFILL }},
    { &hf_ipv6_frag_offset,
      { "Offset",		"ipv6.fragment.offset",
				FT_UINT16, BASE_DEC_HEX, NULL, IP6F_OFF_MASK,
				"Fragment Offset", HFILL }},
    { &hf_ipv6_frag_more,
      { "More Fragment",	"ipv6.fragment.more",
				FT_BOOLEAN, 16, TFS(&tfs_yes_no), IP6F_MORE_FRAG,
				"More Fragments", HFILL }},
    { &hf_ipv6_frag_id,
      { "Identification",	"ipv6.framgent.id",
				FT_UINT32, BASE_HEX, NULL, 0x0,
				"Fragment Identification", HFILL }},
    { &hf_ipv6_fragment_overlap,
      { "Fragment overlap",	"ipv6.fragment.overlap",
				FT_BOOLEAN, BASE_NONE, NULL, 0x0,
				"Fragment overlaps with other fragments", HFILL }},

    { &hf_ipv6_fragment_overlap_conflict,
      { "Conflicting data in fragment overlap",	"ipv6.fragment.overlap.conflict",
				FT_BOOLEAN, BASE_NONE, NULL, 0x0,
				"Overlapping fragments contained conflicting data", HFILL }},

    { &hf_ipv6_fragment_multiple_tails,
      { "Multiple tail fragments found", "ipv6.fragment.multipletails",
				FT_BOOLEAN, BASE_NONE, NULL, 0x0,
				"Several tails were found when defragmenting the packet", HFILL }},

    { &hf_ipv6_fragment_too_long_fragment,
      { "Fragment too long",	"ipv6.fragment.toolongfragment",
				FT_BOOLEAN, BASE_NONE, NULL, 0x0,
				"Fragment contained data past end of packet", HFILL }},

    { &hf_ipv6_fragment_error,
      { "Defragmentation error", "ipv6.fragment.error",
				FT_FRAMENUM, BASE_NONE, NULL, 0x0,
				"Defragmentation error due to illegal fragments", HFILL }},

    { &hf_ipv6_fragment,
      { "IPv6 Fragment",	"ipv6.fragment",
				FT_FRAMENUM, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_fragments,
      { "IPv6 Fragments",	"ipv6.fragments",
				FT_NONE, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_reassembled_in,
      { "Reassembled IPv6 in frame", "ipv6.reassembled_in",
				FT_FRAMENUM, BASE_NONE, NULL, 0x0,
				"This IPv6 packet is reassembled in this frame", HFILL }},

    /* Mobile IPv6 */
    { &hf_ipv6_mipv6_type,
      { "Option Type",		"ipv6.mipv6_type",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},
    { &hf_ipv6_mipv6_length,
      { "Option Length",	"ipv6.mipv6_length",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},
    { &hf_ipv6_mipv6_home_address,
      { "Home Address",	"ipv6.mipv6_home_address",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},

    /* SHIM6 */
    { &hf_ipv6_shim6,
      { "SHIM6",		"ipv6.shim6",
				FT_NONE, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_nxt,
      { "Next Header",		"ipv6.shim6.nxt",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_len,
      { "Header Ext Length", 	"ipv6.shim6.len",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_p,
      { "P Bit", 		"ipv6.shim6.p",
				FT_BOOLEAN, 8, NULL, SHIM6_BITMASK_P,
				NULL, HFILL }},

    { &hf_ipv6_shim6_ct,
      { "Context Tag", 		"ipv6.shim6.ct",
				FT_NONE, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_type,
      { "Message Type", 	"ipv6.shim6.type",
				FT_UINT8, BASE_DEC,
				VALS(shimctrlvals), SHIM6_BITMASK_TYPE,
				NULL, HFILL }},

    { &hf_ipv6_shim6_proto,
      { "Protocol", 		"ipv6.shim6.proto",
				FT_UINT8, BASE_DEC,
				VALS(shim6_protocol), SHIM6_BITMASK_PROTOCOL,
				NULL, HFILL }},

    { &hf_ipv6_shim6_checksum,
      { "Checksum", 		"ipv6.shim6.checksum",
				FT_UINT16, BASE_HEX, NULL, 0x0,
				"Shim6 Checksum", HFILL }},
    { &hf_ipv6_shim6_checksum_bad,
      { "Bad Checksum",		"ipv6.shim6.checksum_bad",
				FT_BOOLEAN, BASE_NONE, NULL, 0x0,
				"Shim6 Bad Checksum", HFILL }},

    { &hf_ipv6_shim6_checksum_good,
      { "Good Checksum",		"ipv6.shim6.checksum_good",
				FT_BOOLEAN, BASE_NONE, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_inonce,
      { "Initiator Nonce", 	"ipv6.shim6.inonce",
				FT_UINT32, BASE_DEC_HEX, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_rnonce,
      { "Responder Nonce", 	"ipv6.shim6.rnonce",
				FT_UINT32, BASE_DEC_HEX, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_precvd,
      { "Probes Received", 	"ipv6.shim6.precvd",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_psent,
      { "Probes Sent", 		"ipv6.shim6.psent",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_psrc,
      { "Source Address",	"ipv6.shim6.psrc",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Shim6 Probe Source Address", HFILL }},

    { &hf_ipv6_shim6_pdst,
      { "Destination Address",	"ipv6.shim6.pdst",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Shim6 Probe Destination Address", HFILL }},

    { &hf_ipv6_shim6_pnonce,
      { "Nonce",		"ipv6.shim6.pnonce",
				FT_UINT32, BASE_DEC_HEX, NULL, 0x0,
				"Shim6 Probe Nonce", HFILL }},

    { &hf_ipv6_shim6_pdata,
      { "Data",			"ipv6.shim6.pdata",
				FT_UINT32, BASE_HEX, NULL, 0x0,
				"Shim6 Probe Data", HFILL }},

    { &hf_ipv6_shim6_sulid,
      { "Sender ULID",		"ipv6.shim6.sulid",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Shim6 Sender ULID", HFILL }},

    { &hf_ipv6_shim6_rulid,
      { "Receiver ULID",	"ipv6.shim6.rulid",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Shim6 Receiver ULID", HFILL }},

    { &hf_ipv6_shim6_reap,
      { "REAP State", 		"ipv6.shim6.reap",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_opt_type,
      { "Option Type", 		"ipv6.shim6.opt.type",
				FT_UINT16, BASE_DEC,
				VALS(shimoptvals), SHIM6_BITMASK_OPT_TYPE,
				"Shim6 Option Type", HFILL }},

    { &hf_ipv6_shim6_opt_critical,
      { "Option Critical Bit", 	"ipv6.shim6.opt.critical",
				FT_BOOLEAN, 8,
				TFS(&tfs_yes_no),
				SHIM6_BITMASK_CRITICAL,
				"TRUE : option is critical, FALSE: option is not critical",
				HFILL }},

    { &hf_ipv6_shim6_opt_len,
      { "Content Length",	"ipv6.shim6.opt.len",
				FT_UINT16, BASE_DEC, NULL, 0x0,
				"Content Length Option", HFILL }},

    { &hf_ipv6_shim6_opt_total_len,
      { "Total Length",		"ipv6.shim6.opt.total_len",
				FT_UINT16, BASE_DEC, NULL, 0x0,
				"Total Option Length", HFILL }},

    { &hf_ipv6_shim6_opt_loc_verif_methods,
      { "Verification Method",	"ipv6.shim6.opt.verif_method",
				FT_UINT8, BASE_DEC,
				VALS(shimverifmethods), 0x0,
				"Locator Verification Method", HFILL }},

    { &hf_ipv6_shim6_opt_loclist,
      { "Locator List Generation", "ipv6.shim6.opt.loclist",
				FT_UINT32, BASE_DEC_HEX, NULL, 0x0,
				NULL, HFILL }},

    { &hf_ipv6_shim6_locator,
      { "Locator",		"ipv6.shim6.locator",
				FT_IPv6, BASE_NONE, NULL, 0x0,
				"Shim6 Locator", HFILL }},

    { &hf_ipv6_shim6_opt_locnum,
      { "Num Locators",		"ipv6.shim6.opt.locnum",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Number of Locators in Locator List", HFILL }},

    { &hf_ipv6_shim6_opt_elemlen,
      { "Element Length",	"ipv6.shim6.opt.elemlen",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Length of Elements in Locator Preferences Option", HFILL }},
    { &hf_ipv6_shim6_loc_flag,
      { "Flags",		"ipv6.shim6.loc.flags",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Locator Preferences Flags", HFILL }},

    { &hf_ipv6_shim6_loc_prio,
      { "Priority",		"ipv6.shim6.loc.prio",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Locator Preferences Priority", HFILL }},

    { &hf_ipv6_shim6_loc_weight,
      { "Weight",		"ipv6.shim6.loc.weight",
				FT_UINT8, BASE_DEC, NULL, 0x0,
				"Locator Preferences Weight", HFILL }},

    { &hf_ipv6_shim6_opt_fii,
      { "Forked Instance Identifier", "ipv6.shim6.opt.fii",
				FT_UINT32, BASE_DEC_HEX, NULL, 0x0,
				NULL, HFILL }},

#ifdef TEST_FINALHDR
    { &hf_ipv6_final,
      { "Final next header",	"ipv6.final",
				FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL }},
#endif

    { &hf_ipv6_traffic_class_dscp,
      { "Differentiated Services Field", 	"ipv6.traffic_class.dscp",
				FT_UINT32, BASE_HEX, VALS(dscp_vals), 0x0FC00000, NULL, HFILL }},

    { &hf_ipv6_traffic_class_ect,
      { "ECN-Capable Transport (ECT)", "ipv6.traffic_class.ect",
				FT_BOOLEAN, 32, TFS(&tfs_set_notset), 0x0200000, NULL, HFILL }},

    { &hf_ipv6_traffic_class_ce,
      { "ECN-CE", 		"ipv6.traffic_class.ce",
				FT_BOOLEAN, 32, TFS(&tfs_set_notset), 0x0100000, NULL, HFILL }},
  };
  static gint *ett[] = {
    &ett_ipv6,
    &ett_ipv6_version,
    &ett_ipv6_shim6,
    &ett_ipv6_shim6_option,
    &ett_ipv6_shim6_locators,
    &ett_ipv6_shim6_verif_methods,
    &ett_ipv6_shim6_loc_pref,
    &ett_ipv6_shim6_probes_sent,
    &ett_ipv6_shim6_probes_rcvd,
    &ett_ipv6_shim6_probe_sent,
    &ett_ipv6_shim6_probe_rcvd,
    &ett_ipv6_shim6_cksum,
    &ett_ipv6_fragments,
    &ett_ipv6_fragment,
    &ett_ipv6_traffic_class
  };
  module_t *ipv6_module;

  proto_ipv6 = proto_register_protocol("Internet Protocol Version 6", "IPv6", "ipv6");
  proto_register_field_array(proto_ipv6, hf, array_length(hf));
  proto_register_subtree_array(ett, array_length(ett));

  /* Register configuration options */
  ipv6_module = prefs_register_protocol(proto_ipv6, NULL);
  prefs_register_bool_preference(ipv6_module, "defragment",
	"Reassemble fragmented IPv6 datagrams",
	"Whether fragmented IPv6 datagrams should be reassembled",
	&ipv6_reassemble);

  register_dissector("ipv6", dissect_ipv6, proto_ipv6);
  register_init_routine(ipv6_reassemble_init);
}

void
proto_reg_handoff_ipv6(void)
{
  dissector_handle_t ipv6_handle;

  data_handle = find_dissector("data");
  ipv6_handle = find_dissector("ipv6");
  dissector_add("ethertype", ETHERTYPE_IPv6, ipv6_handle);
  dissector_add("ppp.protocol", PPP_IPV6, ipv6_handle);
  dissector_add("ppp.protocol", ETHERTYPE_IPv6, ipv6_handle);
  dissector_add("gre.proto", ETHERTYPE_IPv6, ipv6_handle);
  dissector_add("ip.proto", IP_PROTO_IPV6, ipv6_handle);
  dissector_add("null.type", BSD_AF_INET6_BSD, ipv6_handle);
  dissector_add("null.type", BSD_AF_INET6_FREEBSD, ipv6_handle);
  dissector_add("null.type", BSD_AF_INET6_DARWIN, ipv6_handle);
  dissector_add("chdlctype", ETHERTYPE_IPv6, ipv6_handle);
  dissector_add("fr.ietf", NLPID_IP6, ipv6_handle);
  dissector_add("osinl.excl", NLPID_IP6, ipv6_handle);
  dissector_add("x.25.spi", NLPID_IP6, ipv6_handle);
  dissector_add("arcnet.protocol_id", ARCNET_PROTO_IPv6, ipv6_handle);

  ip_dissector_table = find_dissector_table("ip.proto");
}