The Tcpdump Group git mirrors - tcpdump/blob - print-rt6.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 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 /* \summary: IPv6 routing header printer */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include "config.h"
  26 #endif
  27
  28 #include <netdissect-stdinc.h>
  29
  30 #include <string.h>
  31
  32 #include "netdissect.h"
  33 #include "addrtoname.h"
  34 #include "extract.h"
  35
  36 #include "ip6.h"
  37
  38 int
  39 rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
  40 {
  41         const struct ip6_rthdr *dp;
  42         const struct ip6_rthdr0 *dp0;
  43         const u_char *ep;
  44         u_int i, len, type;
  45         const struct in6_addr *addr;
  46
  47         dp = (const struct ip6_rthdr *)bp;
  48
  49         /* 'ep' points to the end of available data. */
  50         ep = ndo->ndo_snapend;
  51
  52         ND_TCHECK(dp->ip6r_segleft);
  53
  54         len = EXTRACT_U_1(dp->ip6r_len);
  55         ND_PRINT((ndo, "srcrt (len=%u", len));  /*)*/
  56         type = EXTRACT_U_1(dp->ip6r_type);
  57         ND_PRINT((ndo, ", type=%u", type));
  58         ND_PRINT((ndo, ", segleft=%u", EXTRACT_U_1(dp->ip6r_segleft)));
  59
  60         switch (type) {
  61         case IPV6_RTHDR_TYPE_0:
  62         case IPV6_RTHDR_TYPE_2:                 /* Mobile IPv6 ID-20 */
  63                 dp0 = (const struct ip6_rthdr0 *)dp;
  64
  65                 ND_TCHECK(dp0->ip6r0_reserved);
  66                 if (EXTRACT_BE_U_4(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
  67                         ND_PRINT((ndo, ", rsv=0x%0x",
  68                             EXTRACT_BE_U_4(dp0->ip6r0_reserved)));
  69                 }
  70
  71                 if (len % 2 == 1)
  72                         goto trunc;
  73                 len >>= 1;
  74                 addr = &dp0->ip6r0_addr[0];
  75                 for (i = 0; i < len; i++) {
  76                         if ((const u_char *)(addr + 1) > ep)
  77                                 goto trunc;
  78
  79                         ND_PRINT((ndo, ", [%d]%s", i, ip6addr_string(ndo, addr)));
  80                         addr++;
  81                 }
  82                 /*(*/
  83                 ND_PRINT((ndo, ") "));
  84                 return((EXTRACT_U_1(dp0->ip6r0_len) + 1) << 3);
  85                 break;
  86         default:
  87                 goto trunc;
  88                 break;
  89         }
  90
  91  trunc:
  92         ND_PRINT((ndo, "[|srcrt]"));
  93         return -1;
  94 }