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   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         const u_char *ep;
  45         u_int i, len, type;
  46         const struct in6_addr *addr;
  47
  48         dp = (const struct ip6_rthdr *)bp;
  49
  50         /* 'ep' points to the end of available data. */
  51         ep = ndo->ndo_snapend;
  52
  53         ND_TCHECK(dp->ip6r_segleft);
  54
  55         len = EXTRACT_U_1(dp->ip6r_len);
  56         ND_PRINT("srcrt (len=%u", len); /*)*/
  57         type = EXTRACT_U_1(dp->ip6r_type);
  58         ND_PRINT(", type=%u", type);
  59         ND_PRINT(", segleft=%u", EXTRACT_U_1(dp->ip6r_segleft));
  60
  61         switch (type) {
  62         case IPV6_RTHDR_TYPE_0:
  63         case IPV6_RTHDR_TYPE_2:                 /* Mobile IPv6 ID-20 */
  64                 dp0 = (const struct ip6_rthdr0 *)dp;
  65
  66                 ND_TCHECK(dp0->ip6r0_reserved);
  67                 if (EXTRACT_BE_U_4(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
  68                         ND_PRINT(", rsv=0x%0x",
  69                             EXTRACT_BE_U_4(dp0->ip6r0_reserved));
  70                 }
  71
  72                 if (len % 2 == 1)
  73                         goto trunc;
  74                 len >>= 1;
  75                 addr = &dp0->ip6r0_addr[0];
  76                 for (i = 0; i < len; i++) {
  77                         if ((const u_char *)(addr + 1) > ep)
  78                                 goto trunc;
  79
  80                         ND_PRINT(", [%d]%s", i, ip6addr_string(ndo, addr));
  81                         addr++;
  82                 }
  83                 /*(*/
  84                 ND_PRINT(") ");
  85                 return((EXTRACT_U_1(dp0->ip6r0_len) + 1) << 3);
  86                 break;
  87         case IPV6_RTHDR_TYPE_4:
  88                 srh = (const struct ip6_srh *)dp;
  89                 ND_PRINT(", last-entry=%u", EXTRACT_U_1(srh->srh_last_ent));
  90
  91                 ND_TCHECK(srh->srh_flags);
  92                 if (EXTRACT_U_1(srh->srh_flags) || ndo->ndo_vflag) {
  93                         ND_PRINT(", flags=0x%0x",
  94                                 EXTRACT_U_1(srh->srh_flags));
  95                 }
  96
  97                 ND_PRINT(", tag=%x", EXTRACT_BE_U_2(srh->srh_tag));
  98
  99                 if (len % 2 == 1)
 100                         goto trunc;
 101                 len >>= 1;
 102                 addr = &srh->srh_segments[0];
 103                 for (i = 0; i < len; i++) {
 104                         if ((const u_char *)(addr + 1) > ep)
 105                                 goto trunc;
 106
 107                         ND_PRINT(", [%d]%s", i, ip6addr_string(ndo, addr));
 108                         addr++;
 109                 }
 110                 /*(*/
 111                 ND_PRINT(") ");
 112                 return((EXTRACT_U_1(srh->srh_len) + 1) << 3);
 113                 break;
 114         default:
 115                 goto trunc;
 116                 break;
 117         }
 118
 119  trunc:
 120         ND_PRINT("[|srcrt]");
 121         return -1;
 122 }