The Tcpdump Group git mirrors - tcpdump/blob - 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 #ifndef lint
  23 static const char rcsid[] _U_ =
  24     "@(#) $Header: /tcpdump/master/tcpdump/print-ip6.c,v 1.42 2004-04-26 17:59:37 hannes Exp $";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #ifdef INET6
  32
  33 #include <tcpdump-stdinc.h>
  34
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 #include "interface.h"
  40 #include "addrtoname.h"
  41 #include "extract.h"
  42
  43 #include "ip6.h"
  44 #include "ipproto.h"
  45
  46 /*
  47  * print an IP6 datagram.
  48  */
  49 void
  50 ip6_print(register const u_char *bp, register u_int length)
  51 {
  52         register const struct ip6_hdr *ip6;
  53         register int advance;
  54         u_int len;
  55         const u_char *ipend;
  56         register const u_char *cp;
  57         register u_int payload_len;
  58         int nh;
  59         int fragmented = 0;
  60         u_int flow;
  61
  62         ip6 = (const struct ip6_hdr *)bp;
  63
  64         TCHECK(*ip6);
  65         if (length < sizeof (struct ip6_hdr)) {
  66                 (void)printf("truncated-ip6 %d", length);
  67                 return;
  68         }
  69
  70         printf("IP6 ");
  71
  72         payload_len = EXTRACT_16BITS(&ip6->ip6_plen);
  73         len = payload_len + sizeof(struct ip6_hdr);
  74         if (length < len)
  75                 (void)printf("truncated-ip6 - %d bytes missing!",
  76                         len - length);
  77
  78         if (vflag) {
  79             flow = EXTRACT_32BITS(&ip6->ip6_flow);
  80             printf("(");
  81 #if 0
  82             /* rfc1883 */
  83             if (flow & 0x0f000000)
  84                 (void)printf("pri 0x%02x, ", (flow & 0x0f000000) >> 24);
  85             if (flow & 0x00ffffff)
  86                 (void)printf("flowlabel 0x%06x, ", flow & 0x00ffffff);
  87 #else
  88             /* RFC 2460 */
  89             if (flow & 0x0ff00000)
  90                 (void)printf("class 0x%02x, ", (flow & 0x0ff00000) >> 20);
  91             if (flow & 0x000fffff)
  92                 (void)printf("flowlabel 0x%05x, ", flow & 0x000fffff);
  93 #endif
  94
  95             (void)printf("hlim %u, next-header: %s (%u), payload-len %u) ",
  96                          ip6->ip6_hlim,
  97                          tok2str(ipproto_values,"unknown",ip6->ip6_nxt),
  98                          ip6->ip6_nxt,
  99                          payload_len);
 100         }
 101
 102         /*
 103          * Cut off the snapshot length to the end of the IP payload.
 104          */
 105         ipend = bp + len;
 106         if (ipend < snapend)
 107                 snapend = ipend;
 108
 109         cp = (const u_char *)ip6;
 110         advance = sizeof(struct ip6_hdr);
 111         nh = ip6->ip6_nxt;
 112         while (cp < snapend && advance > 0) {
 113                 cp += advance;
 114                 len -= advance;
 115
 116                 if (cp == (const u_char *)(ip6 + 1) &&
 117                     nh != IPPROTO_TCP && nh != IPPROTO_UDP &&
 118                     nh != IPPROTO_SCTP) {
 119                         (void)printf("%s > %s: ", ip6addr_string(&ip6->ip6_src),
 120                                      ip6addr_string(&ip6->ip6_dst));
 121                 }
 122
 123                 switch (nh) {
 124                 case IPPROTO_HOPOPTS:
 125                         advance = hbhopt_print(cp);
 126                         nh = *cp;
 127                         break;
 128                 case IPPROTO_DSTOPTS:
 129                         advance = dstopt_print(cp);
 130                         nh = *cp;
 131                         break;
 132                 case IPPROTO_FRAGMENT:
 133                         advance = frag6_print(cp, (const u_char *)ip6);
 134                         if (snapend <= cp + advance)
 135                                 return;
 136                         nh = *cp;
 137                         fragmented = 1;
 138                         break;
 139
 140                 case IPPROTO_MOBILITY_OLD:
 141                 case IPPROTO_MOBILITY:
 142                         /*
 143                          * XXX - we don't use "advance"; the current
 144                          * "Mobility Support in IPv6" draft
 145                          * (draft-ietf-mobileip-ipv6-24) says that
 146                          * the next header field in a mobility header
 147                          * should be IPPROTO_NONE, but speaks of
 148                          * the possiblity of a future extension in
 149                          * which payload can be piggybacked atop a
 150                          * mobility header.
 151                          */
 152                         advance = mobility_print(cp, (const u_char *)ip6);
 153                         nh = *cp;
 154                         return;
 155                 case IPPROTO_ROUTING:
 156                         advance = rt6_print(cp, (const u_char *)ip6);
 157                         nh = *cp;
 158                         break;
 159                 case IPPROTO_SCTP:
 160                         sctp_print(cp, (const u_char *)ip6, len);
 161                         return;
 162                 case IPPROTO_TCP:
 163                         tcp_print(cp, len, (const u_char *)ip6, fragmented);
 164                         return;
 165                 case IPPROTO_UDP:
 166                         udp_print(cp, len, (const u_char *)ip6, fragmented);
 167                         return;
 168                 case IPPROTO_ICMPV6:
 169                         icmp6_print(cp, len, (const u_char *)ip6, fragmented);
 170                         return;
 171                 case IPPROTO_AH:
 172                         advance = ah_print(cp);
 173                         nh = *cp;
 174                         break;
 175                 case IPPROTO_ESP:
 176                     {
 177                         int enh, padlen;
 178                         advance = esp_print(gndo, cp, (const u_char *)ip6, &enh, &padlen);
 179                         nh = enh & 0xff;
 180                         len -= padlen;
 181                         break;
 182                     }
 183                 case IPPROTO_IPCOMP:
 184                     {
 185                         int enh;
 186                         advance = ipcomp_print(cp, &enh);
 187                         nh = enh & 0xff;
 188                         break;
 189                     }
 190
 191                 case IPPROTO_PIM:
 192                         pim_print(cp, len);
 193                         return;
 194                 case IPPROTO_OSPF:
 195                         ospf6_print(cp, len);
 196                         return;
 197
 198                 case IPPROTO_IPV6:
 199                         ip6_print(cp, len);
 200                         return;
 201
 202                 case IPPROTO_IPV4:
 203                         ip_print(cp, len);
 204                         return;
 205
 206                 case IPPROTO_NONE:
 207                         (void)printf("no next header");
 208                         return;
 209
 210                 default:
 211                         (void)printf("ip-proto-%d %d", ip6->ip6_nxt, len);
 212                         return;
 213                 }
 214         }
 215
 216         return;
 217 trunc:
 218         (void)printf("[|ip6]");
 219 }
 220
 221 #endif /* INET6 */