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 struct ip6_srh *srh;
  44         u_int i, len, type;
  45         const u_char *p;
  46
  47         ndo->ndo_protocol = "rt6";
  48         dp = (const struct ip6_rthdr *)bp;
  49
  50         ND_TCHECK_1(dp->ip6r_segleft);
  51
  52         len = GET_U_1(dp->ip6r_len);
  53         ND_PRINT("srcrt (len=%u", len); /*)*/
  54         type = GET_U_1(dp->ip6r_type);
  55         ND_PRINT(", type=%u", type);
  56         ND_PRINT(", segleft=%u", GET_U_1(dp->ip6r_segleft));
  57
  58         switch (type) {
  59         case IPV6_RTHDR_TYPE_0:
  60         case IPV6_RTHDR_TYPE_2:                 /* Mobile IPv6 ID-20 */
  61                 dp0 = (const struct ip6_rthdr0 *)dp;
  62
  63                 ND_TCHECK_4(dp0->ip6r0_reserved);
  64                 if (GET_BE_U_4(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
  65                         ND_PRINT(", rsv=0x%0x",
  66                             GET_BE_U_4(dp0->ip6r0_reserved));
  67                 }
  68
  69                 if (len % 2 == 1)
  70                         goto trunc;
  71                 len >>= 1;
  72                 p = (const u_char *) dp0->ip6r0_addr;
  73                 for (i = 0; i < len; i++) {
  74                         ND_TCHECK_16(p);
  75                         ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
  76                         p += 16;
  77                 }
  78                 /*(*/
  79                 ND_PRINT(") ");
  80                 return((GET_U_1(dp0->ip6r0_len) + 1) << 3);
  81                 break;
  82         case IPV6_RTHDR_TYPE_4:
  83                 srh = (const struct ip6_srh *)dp;
  84                 ND_TCHECK_1(srh->srh_last_ent);
  85                 ND_PRINT(", last-entry=%u", GET_U_1(srh->srh_last_ent));
  86
  87                 ND_TCHECK_1(srh->srh_flags);
  88                 if (GET_U_1(srh->srh_flags) || ndo->ndo_vflag) {
  89                         ND_PRINT(", flags=0x%0x",
  90                                 GET_U_1(srh->srh_flags));
  91                 }
  92
  93                 ND_TCHECK_2(srh->srh_tag);
  94                 ND_PRINT(", tag=%x", GET_BE_U_2(srh->srh_tag));
  95
  96                 if (len % 2 == 1)
  97                         goto trunc;
  98                 len >>= 1;
  99                 p  = (const u_char *) srh->srh_segments;
 100                 for (i = 0; i < len; i++) {
 101                         ND_TCHECK_16(p);
 102                         ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
 103                         p += 16;
 104                 }
 105                 /*(*/
 106                 ND_PRINT(") ");
 107                 return((GET_U_1(srh->srh_len) + 1) << 3);
 108                 break;
 109         default:
 110                 goto trunc;
 111                 break;
 112         }
 113
 114  trunc:
 115         ND_PRINT("[|srcrt]");
 116         return -1;
 117 }