xref: /freebsd/contrib/tcpdump/print-frag6.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
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 */
96