xref: /freebsd/contrib/tcpdump/print-rt6.c (revision 63a938566d524836885917d95bd491aa4400b181)
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, register const u_char *bp, const u_char *bp2 _U_)
40 {
41 	register const struct ip6_rthdr *dp;
42 	register const struct ip6_rthdr0 *dp0;
43 	register const u_char *ep;
44 	int i, len;
45 	register 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 = dp->ip6r_len;
55 	ND_PRINT((ndo, "srcrt (len=%d", dp->ip6r_len));	/*)*/
56 	ND_PRINT((ndo, ", type=%d", dp->ip6r_type));
57 	ND_PRINT((ndo, ", segleft=%d", dp->ip6r_segleft));
58 
59 	switch (dp->ip6r_type) {
60 	case IPV6_RTHDR_TYPE_0:
61 	case IPV6_RTHDR_TYPE_2:			/* Mobile IPv6 ID-20 */
62 		dp0 = (const struct ip6_rthdr0 *)dp;
63 
64 		ND_TCHECK(dp0->ip6r0_reserved);
65 		if (EXTRACT_32BITS(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
66 			ND_PRINT((ndo, ", rsv=0x%0x",
67 			    EXTRACT_32BITS(&dp0->ip6r0_reserved)));
68 		}
69 
70 		if (len % 2 == 1)
71 			goto trunc;
72 		len >>= 1;
73 		addr = &dp0->ip6r0_addr[0];
74 		for (i = 0; i < len; i++) {
75 			if ((const u_char *)(addr + 1) > ep)
76 				goto trunc;
77 
78 			ND_PRINT((ndo, ", [%d]%s", i, ip6addr_string(ndo, addr)));
79 			addr++;
80 		}
81 		/*(*/
82 		ND_PRINT((ndo, ") "));
83 		return((dp0->ip6r0_len + 1) << 3);
84 		break;
85 	default:
86 		goto trunc;
87 		break;
88 	}
89 
90  trunc:
91 	ND_PRINT((ndo, "[|srcrt]"));
92 	return -1;
93 }
94