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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 #ifndef lint
  23 static const char rcsid[] =
  24     "@(#) $Header: /tcpdump/master/tcpdump/print-frag6.c,v 1.12 2000-10-07 05:53:10 itojun Exp $";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #ifdef INET6
  32
  33 #include <sys/param.h>
  34 #include <sys/time.h>
  35 #include <sys/types.h>
  36 #include <sys/socket.h>
  37
  38
  39 #include <netinet/in.h>
  40
  41 #include <stdio.h>
  42
  43 #include "ip6.h"
  44
  45 #include "interface.h"
  46 #include "addrtoname.h"
  47
  48 int
  49 frag6_print(register const u_char *bp, register const u_char *bp2)
  50 {
  51         register const struct ip6_frag *dp;
  52         register const struct ip6_hdr *ip6;
  53         register const u_char *ep;
  54
  55 #if 0
  56 #define TCHECK(var) if ((u_char *)&(var) >= ep - sizeof(var)) goto trunc
  57 #endif
  58
  59         dp = (struct ip6_frag *)bp;
  60         ip6 = (struct ip6_hdr *)bp2;
  61
  62         /* 'ep' points to the end of available data. */
  63         ep = snapend;
  64
  65         TCHECK(dp->ip6f_offlg);
  66
  67         if (vflag) {
  68                 printf("frag (0x%08x:%d|%ld)",
  69                        (u_int32_t)ntohl(dp->ip6f_ident),
  70                        ntohs(dp->ip6f_offlg & IP6F_OFF_MASK),
  71                        sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) -
  72                                (long)(bp - bp2) - sizeof(struct ip6_frag));
  73         } else {
  74                 printf("frag (%d|%ld)",
  75                        ntohs(dp->ip6f_offlg & IP6F_OFF_MASK),
  76                        sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) -
  77                                (long)(bp - bp2) - sizeof(struct ip6_frag));
  78         }
  79
  80 #if 1
  81         /* it is meaningless to decode non-first fragment */
  82         if (ntohs(dp->ip6f_offlg & IP6F_OFF_MASK) != 0)
  83                 return 65535;
  84         else
  85 #endif
  86         {
  87                 fputs(" ", stdout);
  88                 return sizeof(struct ip6_frag);
  89         }
  90 trunc:
  91         fputs("[|frag]", stdout);
  92         return 65535;
  93 #undef TCHECK
  94 }
  95 #endif /* INET6 */