external/bsd/tcpdump/dist/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
  22 #include <sys/cdefs.h>
  23 #ifndef lint
  24 __RCSID("$NetBSD: print-ip6.c,v 1.5 2015/03/31 21:59:35 christos Exp $");
  25 #endif
  26
  27 #define NETDISSECT_REWORKED
  28 #ifdef HAVE_CONFIG_H
  29 #include "config.h"
  30 #endif
  31
  32 #include <tcpdump-stdinc.h>
  33
  34 #include <string.h>
  35
  36 #include "interface.h"
  37 #include "addrtoname.h"
  38 #include "extract.h"
  39
  40 #ifdef INET6
  41
  42 #include "ip6.h"
  43 #include "ipproto.h"
  44
  45 /*
  46  * Compute a V6-style checksum by building a pseudoheader.
  47  */
  48 int
  49 nextproto6_cksum(const struct ip6_hdr *ip6, const uint8_t *data,
  50                  u_int len, u_int covlen, u_int next_proto)
  51 {
  52         struct {
  53                 struct in6_addr ph_src;
  54                 struct in6_addr ph_dst;
  55                 uint32_t       ph_len;
  56                 uint8_t        ph_zero[3];
  57                 uint8_t        ph_nxt;
  58         } ph;
  59         struct cksum_vec vec[2];
  60
  61         /* pseudo-header */
  62         memset(&ph, 0, sizeof(ph));
  63         UNALIGNED_MEMCPY(&ph.ph_src, &ip6->ip6_src, sizeof (struct in6_addr));
  64         UNALIGNED_MEMCPY(&ph.ph_dst, &ip6->ip6_dst, sizeof (struct in6_addr));
  65         ph.ph_len = htonl(len);
  66         ph.ph_nxt = next_proto;
  67
  68         vec[0].ptr = (const uint8_t *)(void *)&ph;
  69         vec[0].len = sizeof(ph);
  70         vec[1].ptr = data;
  71         vec[1].len = covlen;
  72
  73         return in_cksum(vec, 2);
  74 }
  75
  76 /*
  77  * print an IP6 datagram.
  78  */
  79 void
  80 ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
  81 {
  82         register const struct ip6_hdr *ip6;
  83         register int advance;
  84         u_int len;
  85         const u_char *ipend;
  86         register const u_char *cp;
  87         register u_int payload_len;
  88         int nh;
  89         int fragmented = 0;
  90         u_int flow;
  91
  92         ip6 = (const struct ip6_hdr *)bp;
  93
  94         ND_TCHECK(*ip6);
  95         if (length < sizeof (struct ip6_hdr)) {
  96                 ND_PRINT((ndo, "truncated-ip6 %u", length));
  97                 return;
  98         }
  99
 100         if (!ndo->ndo_eflag)
 101             ND_PRINT((ndo, "IP6 "));
 102
 103         if (IP6_VERSION(ip6) != 6) {
 104           ND_PRINT((ndo,"version error: %u != 6", IP6_VERSION(ip6)));
 105           return;
 106         }
 107
 108         payload_len = EXTRACT_16BITS(&ip6->ip6_plen);
 109         len = payload_len + sizeof(struct ip6_hdr);
 110         if (length < len)
 111                 ND_PRINT((ndo, "truncated-ip6 - %u bytes missing!",
 112                         len - length));
 113
 114         if (ndo->ndo_vflag) {
 115             flow = EXTRACT_32BITS(&ip6->ip6_flow);
 116             ND_PRINT((ndo, "("));
 117 #if 0
 118             /* rfc1883 */
 119             if (flow & 0x0f000000)
 120                 ND_PRINT((ndo, "pri 0x%02x, ", (flow & 0x0f000000) >> 24));
 121             if (flow & 0x00ffffff)
 122                 ND_PRINT((ndo, "flowlabel 0x%06x, ", flow & 0x00ffffff));
 123 #else
 124             /* RFC 2460 */
 125             if (flow & 0x0ff00000)
 126                 ND_PRINT((ndo, "class 0x%02x, ", (flow & 0x0ff00000) >> 20));
 127             if (flow & 0x000fffff)
 128                 ND_PRINT((ndo, "flowlabel 0x%05x, ", flow & 0x000fffff));
 129 #endif
 130
 131             ND_PRINT((ndo, "hlim %u, next-header %s (%u) payload length: %u) ",
 132                          ip6->ip6_hlim,
 133                          tok2str(ipproto_values,"unknown",ip6->ip6_nxt),
 134                          ip6->ip6_nxt,
 135                          payload_len));
 136         }
 137
 138         /*
 139          * Cut off the snapshot length to the end of the IP payload.
 140          */
 141         ipend = bp + len;
 142         if (ipend < ndo->ndo_snapend)
 143                 ndo->ndo_snapend = ipend;
 144
 145         cp = (const u_char *)ip6;
 146         advance = sizeof(struct ip6_hdr);
 147         nh = ip6->ip6_nxt;
 148         while (cp < ndo->ndo_snapend && advance > 0) {
 149                 cp += advance;
 150                 len -= advance;
 151
 152                 if (cp == (const u_char *)(ip6 + 1) &&
 153                     nh != IPPROTO_TCP && nh != IPPROTO_UDP &&
 154                     nh != IPPROTO_DCCP && nh != IPPROTO_SCTP) {
 155                         ND_PRINT((ndo, "%s > %s: ", ip6addr_string(ndo, &ip6->ip6_src),
 156                                      ip6addr_string(ndo, &ip6->ip6_dst)));
 157                 }
 158
 159                 switch (nh) {
 160                 case IPPROTO_HOPOPTS:
 161                         advance = hbhopt_print(ndo, cp);
 162                         nh = *cp;
 163                         break;
 164                 case IPPROTO_DSTOPTS:
 165                         advance = dstopt_print(ndo, cp);
 166                         nh = *cp;
 167                         break;
 168                 case IPPROTO_FRAGMENT:
 169                         advance = frag6_print(ndo, cp, (const u_char *)ip6);
 170                         if (ndo->ndo_snapend <= cp + advance)
 171                                 return;
 172                         nh = *cp;
 173                         fragmented = 1;
 174                         break;
 175
 176                 case IPPROTO_MOBILITY_OLD:
 177                 case IPPROTO_MOBILITY:
 178                         /*
 179                          * XXX - we don't use "advance"; the current
 180                          * "Mobility Support in IPv6" draft
 181                          * (draft-ietf-mobileip-ipv6-24) says that
 182                          * the next header field in a mobility header
 183                          * should be IPPROTO_NONE, but speaks of
 184                          * the possiblity of a future extension in
 185                          * which payload can be piggybacked atop a
 186                          * mobility header.
 187                          */
 188                         advance = mobility_print(ndo, cp, (const u_char *)ip6);
 189                         nh = *cp;
 190                         return;
 191                 case IPPROTO_ROUTING:
 192                         advance = rt6_print(ndo, cp, (const u_char *)ip6);
 193                         nh = *cp;
 194                         break;
 195                 case IPPROTO_SCTP:
 196                         sctp_print(ndo, cp, (const u_char *)ip6, len);
 197                         return;
 198                 case IPPROTO_DCCP:
 199                         dccp_print(ndo, cp, (const u_char *)ip6, len);
 200                         return;
 201                 case IPPROTO_TCP:
 202                         tcp_print(ndo, cp, len, (const u_char *)ip6, fragmented);
 203                         return;
 204                 case IPPROTO_UDP:
 205                         udp_print(ndo, cp, len, (const u_char *)ip6, fragmented);
 206                         return;
 207                 case IPPROTO_ICMPV6:
 208                         icmp6_print(ndo, cp, len, (const u_char *)ip6, fragmented);
 209                         return;
 210                 case IPPROTO_AH:
 211                         advance = ah_print(ndo, cp);
 212                         nh = *cp;
 213                         break;
 214                 case IPPROTO_ESP:
 215                     {
 216                         int enh, padlen;
 217                         advance = esp_print(ndo, cp, len, (const u_char *)ip6, &enh, &padlen);
 218                         nh = enh & 0xff;
 219                         len -= padlen;
 220                         break;
 221                     }
 222                 case IPPROTO_IPCOMP:
 223                     {
 224                         int enh;
 225                         advance = ipcomp_print(ndo, cp, &enh);
 226                         nh = enh & 0xff;
 227                         break;
 228                     }
 229
 230                 case IPPROTO_PIM:
 231                         pim_print(ndo, cp, len, nextproto6_cksum(ip6, cp, len, len,
 232                                                             IPPROTO_PIM));
 233                         return;
 234
 235                 case IPPROTO_OSPF:
 236                         ospf6_print(ndo, cp, len);
 237                         return;
 238
 239                 case IPPROTO_IPV6:
 240                         ip6_print(ndo, cp, len);
 241                         return;
 242
 243                 case IPPROTO_IPV4:
 244                         ip_print(ndo, cp, len);
 245                         return;
 246
 247                 case IPPROTO_PGM:
 248                         pgm_print(ndo, cp, len, (const u_char *)ip6);
 249                         return;
 250
 251                 case IPPROTO_GRE:
 252                         gre_print(ndo, cp, len);
 253                         return;
 254
 255                 case IPPROTO_RSVP:
 256                         rsvp_print(ndo, cp, len);
 257                         return;
 258
 259                 case IPPROTO_NONE:
 260                         ND_PRINT((ndo, "no next header"));
 261                         return;
 262
 263                 default:
 264                         ND_PRINT((ndo, "ip-proto-%d %d", nh, len));
 265                         return;
 266                 }
 267         }
 268
 269         return;
 270 trunc:
 271         ND_PRINT((ndo, "[|ip6]"));
 272 }
 273
 274 #else /* INET6 */
 275
 276 void
 277 ip6_print(netdissect_options *ndo, const u_char *bp _U_, u_int length)
 278 {
 279         ND_PRINT((ndo, "IP6, length: %u (printing not supported)", length));
 280 }
 281
 282 #endif /* INET6 */