contrib/tcpdump/print-ip6.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  *
  21  * $FreeBSD$
  22  */
  23
  24 #ifndef lint
  25 static const char rcsid[] _U_ =
  26     "@(#) $Header: /tcpdump/master/tcpdump/print-ip6.c,v 1.52 2007-09-21 07:05:33 hannes Exp $";
  27 #endif
  28
  29 #ifdef HAVE_CONFIG_H
  30 #include "config.h"
  31 #endif
  32
  33 #ifdef INET6
  34
  35 #include <tcpdump-stdinc.h>
  36
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40
  41 #include "netdissect.h"
  42 #include "interface.h"
  43 #include "addrtoname.h"
  44 #include "extract.h"
  45
  46 #include "ip6.h"
  47 #include "ipproto.h"
  48
  49 /*
  50  * Compute a V6-style checksum by building a pseudoheader.
  51  */
  52 int
  53 nextproto6_cksum(const struct ip6_hdr *ip6, const u_short *data,
  54                  u_int len, u_int next_proto)
  55 {
  56         size_t i;
  57         u_int32_t sum = 0;
  58         union ip6_pseudo_hdr phu;
  59
  60         /* pseudo-header */
  61         memset(&phu, 0, sizeof(phu));
  62         phu.ph.ph_src = ip6->ip6_src;
  63         phu.ph.ph_dst = ip6->ip6_dst;
  64         phu.ph.ph_len = htonl(len);
  65         phu.ph.ph_nxt = next_proto;
  66
  67         for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++) {
  68                 sum += phu.pa[i];
  69         }
  70
  71         return in_cksum(data, len, sum);
  72 }
  73
  74 /*
  75  * print an IP6 datagram.
  76  */
  77 void
  78 ip6_print(register const u_char *bp, register u_int length)
  79 {
  80         register const struct ip6_hdr *ip6;
  81         register int advance;
  82         u_int len;
  83         const u_char *ipend;
  84         register const u_char *cp;
  85         register u_int payload_len;
  86         int nh;
  87         int fragmented = 0;
  88         u_int flow;
  89
  90         ip6 = (const struct ip6_hdr *)bp;
  91
  92         TCHECK(*ip6);
  93         if (length < sizeof (struct ip6_hdr)) {
  94                 (void)printf("truncated-ip6 %u", length);
  95                 return;
  96         }
  97
  98         if (!eflag)
  99             printf("IP6 ");
 100
 101         payload_len = EXTRACT_16BITS(&ip6->ip6_plen);
 102         len = payload_len + sizeof(struct ip6_hdr);
 103         if (length < len)
 104                 (void)printf("truncated-ip6 - %u bytes missing!",
 105                         len - length);
 106
 107         if (vflag) {
 108             flow = EXTRACT_32BITS(&ip6->ip6_flow);
 109             printf("(");
 110 #if 0
 111             /* rfc1883 */
 112             if (flow & 0x0f000000)
 113                 (void)printf("pri 0x%02x, ", (flow & 0x0f000000) >> 24);
 114             if (flow & 0x00ffffff)
 115                 (void)printf("flowlabel 0x%06x, ", flow & 0x00ffffff);
 116 #else
 117             /* RFC 2460 */
 118             if (flow & 0x0ff00000)
 119                 (void)printf("class 0x%02x, ", (flow & 0x0ff00000) >> 20);
 120             if (flow & 0x000fffff)
 121                 (void)printf("flowlabel 0x%05x, ", flow & 0x000fffff);
 122 #endif
 123
 124             (void)printf("hlim %u, next-header %s (%u) payload length: %u) ",
 125                          ip6->ip6_hlim,
 126                          tok2str(ipproto_values,"unknown",ip6->ip6_nxt),
 127                          ip6->ip6_nxt,
 128                          payload_len);
 129         }
 130
 131         /*
 132          * Cut off the snapshot length to the end of the IP payload.
 133          */
 134         ipend = bp + len;
 135         if (ipend < snapend)
 136                 snapend = ipend;
 137
 138         cp = (const u_char *)ip6;
 139         advance = sizeof(struct ip6_hdr);
 140         nh = ip6->ip6_nxt;
 141         while (cp < snapend && advance > 0) {
 142                 cp += advance;
 143                 len -= advance;
 144
 145                 if (cp == (const u_char *)(ip6 + 1) &&
 146                     nh != IPPROTO_TCP && nh != IPPROTO_UDP &&
 147                     nh != IPPROTO_DCCP && nh != IPPROTO_SCTP) {
 148                         (void)printf("%s > %s: ", ip6addr_string(&ip6->ip6_src),
 149                                      ip6addr_string(&ip6->ip6_dst));
 150                 }
 151
 152                 switch (nh) {
 153                 case IPPROTO_HOPOPTS:
 154                         advance = hbhopt_print(cp);
 155                         nh = *cp;
 156                         break;
 157                 case IPPROTO_DSTOPTS:
 158                         advance = dstopt_print(cp);
 159                         nh = *cp;
 160                         break;
 161                 case IPPROTO_FRAGMENT:
 162                         advance = frag6_print(cp, (const u_char *)ip6);
 163                         if (snapend <= cp + advance)
 164                                 return;
 165                         nh = *cp;
 166                         fragmented = 1;
 167                         break;
 168
 169                 case IPPROTO_MOBILITY_OLD:
 170                 case IPPROTO_MOBILITY:
 171                         /*
 172                          * XXX - we don't use "advance"; the current
 173                          * "Mobility Support in IPv6" draft
 174                          * (draft-ietf-mobileip-ipv6-24) says that
 175                          * the next header field in a mobility header
 176                          * should be IPPROTO_NONE, but speaks of
 177                          * the possiblity of a future extension in
 178                          * which payload can be piggybacked atop a
 179                          * mobility header.
 180                          */
 181                         advance = mobility_print(cp, (const u_char *)ip6);
 182                         nh = *cp;
 183                         return;
 184                 case IPPROTO_ROUTING:
 185                         advance = rt6_print(cp, (const u_char *)ip6);
 186                         nh = *cp;
 187                         break;
 188                 case IPPROTO_SCTP:
 189                         sctp_print(cp, (const u_char *)ip6, len);
 190                         return;
 191                 case IPPROTO_DCCP:
 192                         dccp_print(cp, (const u_char *)ip6, len);
 193                         return;
 194                 case IPPROTO_TCP:
 195                         tcp_print(cp, len, (const u_char *)ip6, fragmented);
 196                         return;
 197                 case IPPROTO_UDP:
 198                         udp_print(cp, len, (const u_char *)ip6, fragmented);
 199                         return;
 200                 case IPPROTO_ICMPV6:
 201                         icmp6_print(gndo, cp, len, (const u_char *)ip6, fragmented);
 202                         return;
 203                 case IPPROTO_AH:
 204                         advance = ah_print(cp);
 205                         nh = *cp;
 206                         break;
 207                 case IPPROTO_ESP:
 208                     {
 209                         int enh, padlen;
 210                         advance = esp_print(gndo, cp, len, (const u_char *)ip6, &enh, &padlen);
 211                         nh = enh & 0xff;
 212                         len -= padlen;
 213                         break;
 214                     }
 215                 case IPPROTO_IPCOMP:
 216                     {
 217                         int enh;
 218                         advance = ipcomp_print(cp, &enh);
 219                         nh = enh & 0xff;
 220                         break;
 221                     }
 222
 223                 case IPPROTO_PIM:
 224                         pim_print(cp, len, nextproto6_cksum(ip6, (u_short *)cp, len,
 225                                                             IPPROTO_PIM));
 226                         return;
 227
 228                 case IPPROTO_OSPF:
 229                         ospf6_print(cp, len);
 230                         return;
 231
 232                 case IPPROTO_IPV6:
 233                         ip6_print(cp, len);
 234                         return;
 235
 236                 case IPPROTO_IPV4:
 237                         ip_print(gndo, cp, len);
 238                         return;
 239
 240                 case IPPROTO_PGM:
 241                         pgm_print(cp, len, (const u_char *)ip6);
 242                         return;
 243
 244                 case IPPROTO_GRE:
 245                         gre_print(cp, len);
 246                         return;
 247
 248                 case IPPROTO_RSVP:
 249                         rsvp_print(cp, len);
 250                         return;
 251
 252                 case IPPROTO_NONE:
 253                         (void)printf("no next header");
 254                         return;
 255
 256                 default:
 257                         (void)printf("ip-proto-%d %d", nh, len);
 258                         return;
 259                 }
 260         }
 261
 262         return;
 263 trunc:
 264         (void)printf("[|ip6]");
 265 }
 266
 267 #endif /* INET6 */