The Tcpdump Group git mirrors - tcpdump/blob - print-ip6opts.c

   1 /*
   2  * Copyright (C) 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #ifdef HAVE_CONFIG_H
  31 #include "config.h"
  32 #endif
  33
  34 #include <netdissect-stdinc.h>
  35
  36 #include "ip6.h"
  37
  38 #include "netdissect.h"
  39 #include "addrtoname.h"
  40 #include "extract.h"
  41
  42 static void
  43 ip6_sopt_print(netdissect_options *ndo, const u_char *bp, int len)
  44 {
  45     int i;
  46     int optlen;
  47
  48     for (i = 0; i < len; i += optlen) {
  49         if (bp[i] == IP6OPT_PAD1)
  50             optlen = 1;
  51         else {
  52             if (i + 1 < len)
  53                 optlen = bp[i + 1] + 2;
  54             else
  55                 goto trunc;
  56         }
  57         if (i + optlen > len)
  58             goto trunc;
  59
  60         switch (bp[i]) {
  61         case IP6OPT_PAD1:
  62             ND_PRINT((ndo, ", pad1"));
  63             break;
  64         case IP6OPT_PADN:
  65             if (len - i < IP6OPT_MINLEN) {
  66                 ND_PRINT((ndo, ", padn: trunc"));
  67                 goto trunc;
  68             }
  69             ND_PRINT((ndo, ", padn"));
  70             break;
  71         default:
  72             if (len - i < IP6OPT_MINLEN) {
  73                 ND_PRINT((ndo, ", sopt_type %d: trunc)", bp[i]));
  74                 goto trunc;
  75             }
  76             ND_PRINT((ndo, ", sopt_type 0x%02x: len=%d", bp[i], bp[i + 1]));
  77             break;
  78         }
  79     }
  80     return;
  81
  82 trunc:
  83     ND_PRINT((ndo, "[trunc] "));
  84 }
  85
  86 static void
  87 ip6_opt_print(netdissect_options *ndo, const u_char *bp, int len)
  88 {
  89     int i;
  90     int optlen = 0;
  91
  92     if (len == 0)
  93         return;
  94     for (i = 0; i < len; i += optlen) {
  95         if (bp[i] == IP6OPT_PAD1)
  96             optlen = 1;
  97         else {
  98             if (i + 1 < len)
  99                 optlen = bp[i + 1] + 2;
 100             else
 101                 goto trunc;
 102         }
 103         if (i + optlen > len)
 104             goto trunc;
 105
 106         switch (bp[i]) {
 107         case IP6OPT_PAD1:
 108             ND_PRINT((ndo, "(pad1)"));
 109             break;
 110         case IP6OPT_PADN:
 111             if (len - i < IP6OPT_MINLEN) {
 112                 ND_PRINT((ndo, "(padn: trunc)"));
 113                 goto trunc;
 114             }
 115             ND_PRINT((ndo, "(padn)"));
 116             break;
 117         case IP6OPT_ROUTER_ALERT:
 118             if (len - i < IP6OPT_RTALERT_LEN) {
 119                 ND_PRINT((ndo, "(rtalert: trunc)"));
 120                 goto trunc;
 121             }
 122             if (bp[i + 1] != IP6OPT_RTALERT_LEN - 2) {
 123                 ND_PRINT((ndo, "(rtalert: invalid len %d)", bp[i + 1]));
 124                 goto trunc;
 125             }
 126             ND_PRINT((ndo, "(rtalert: 0x%04x) ", EXTRACT_16BITS(&bp[i + 2])));
 127             break;
 128         case IP6OPT_JUMBO:
 129             if (len - i < IP6OPT_JUMBO_LEN) {
 130                 ND_PRINT((ndo, "(jumbo: trunc)"));
 131                 goto trunc;
 132             }
 133             if (bp[i + 1] != IP6OPT_JUMBO_LEN - 2) {
 134                 ND_PRINT((ndo, "(jumbo: invalid len %d)", bp[i + 1]));
 135                 goto trunc;
 136             }
 137             ND_PRINT((ndo, "(jumbo: %u) ", EXTRACT_32BITS(&bp[i + 2])));
 138             break;
 139         case IP6OPT_HOME_ADDRESS:
 140             if (len - i < IP6OPT_HOMEADDR_MINLEN) {
 141                 ND_PRINT((ndo, "(homeaddr: trunc)"));
 142                 goto trunc;
 143             }
 144             if (bp[i + 1] < IP6OPT_HOMEADDR_MINLEN - 2) {
 145                 ND_PRINT((ndo, "(homeaddr: invalid len %d)", bp[i + 1]));
 146                 goto trunc;
 147             }
 148             ND_PRINT((ndo, "(homeaddr: %s", ip6addr_string(ndo, &bp[i + 2])));
 149             if (bp[i + 1] > IP6OPT_HOMEADDR_MINLEN - 2) {
 150                 ip6_sopt_print(ndo, &bp[i + IP6OPT_HOMEADDR_MINLEN],
 151                     (optlen - IP6OPT_HOMEADDR_MINLEN));
 152             }
 153             ND_PRINT((ndo, ")"));
 154             break;
 155         default:
 156             if (len - i < IP6OPT_MINLEN) {
 157                 ND_PRINT((ndo, "(type %d: trunc)", bp[i]));
 158                 goto trunc;
 159             }
 160             ND_PRINT((ndo, "(opt_type 0x%02x: len=%d)", bp[i], bp[i + 1]));
 161             break;
 162         }
 163     }
 164     ND_PRINT((ndo, " "));
 165     return;
 166
 167 trunc:
 168     ND_PRINT((ndo, "[trunc] "));
 169 }
 170
 171 int
 172 hbhopt_print(netdissect_options *ndo, register const u_char *bp)
 173 {
 174     const struct ip6_hbh *dp = (const struct ip6_hbh *)bp;
 175     int hbhlen = 0;
 176
 177     ND_TCHECK(dp->ip6h_len);
 178     hbhlen = (int)((dp->ip6h_len + 1) << 3);
 179     ND_TCHECK2(*dp, hbhlen);
 180     ND_PRINT((ndo, "HBH "));
 181     if (ndo->ndo_vflag)
 182         ip6_opt_print(ndo, (const u_char *)dp + sizeof(*dp), hbhlen - sizeof(*dp));
 183
 184     return(hbhlen);
 185
 186   trunc:
 187     ND_PRINT((ndo, "[|HBH]"));
 188     return(-1);
 189 }
 190
 191 int
 192 dstopt_print(netdissect_options *ndo, register const u_char *bp)
 193 {
 194     const struct ip6_dest *dp = (const struct ip6_dest *)bp;
 195     int dstoptlen = 0;
 196
 197     ND_TCHECK(dp->ip6d_len);
 198     dstoptlen = (int)((dp->ip6d_len + 1) << 3);
 199     ND_TCHECK2(*dp, dstoptlen);
 200     ND_PRINT((ndo, "DSTOPT "));
 201     if (ndo->ndo_vflag) {
 202         ip6_opt_print(ndo, (const u_char *)dp + sizeof(*dp),
 203             dstoptlen - sizeof(*dp));
 204     }
 205
 206     return(dstoptlen);
 207
 208   trunc:
 209     ND_PRINT((ndo, "[|DSTOPT]"));
 210     return(-1);
 211 }