xref: /netbsd-src/external/bsd/tcpdump/dist/print-rt6.c (revision ccd9df534e375a4366c5b55f23782053c7a98d82)
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 #include <sys/cdefs.h>
23 #ifndef lint
24 __RCSID("$NetBSD: print-rt6.c,v 1.8 2023/08/17 20:19:40 christos Exp $");
25 #endif
26 
27 /* \summary: IPv6 routing header printer */
28 
29 #ifdef HAVE_CONFIG_H
30 #include <config.h>
31 #endif
32 
33 #include "netdissect-stdinc.h"
34 
35 #include "netdissect.h"
36 #include "addrtoname.h"
37 #include "extract.h"
38 
39 #include "ip6.h"
40 
41 int
42 rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
43 {
44 	const struct ip6_rthdr *dp;
45 	const struct ip6_rthdr0 *dp0;
46 	const struct ip6_srh *srh;
47 	u_int i, len, type;
48 	const u_char *p;
49 
50 	ndo->ndo_protocol = "rt6";
51 
52 	nd_print_protocol_caps(ndo);
53 	dp = (const struct ip6_rthdr *)bp;
54 
55 	len = GET_U_1(dp->ip6r_len);
56 	ND_PRINT(" (len=%u", len);	/*)*/
57 	type = GET_U_1(dp->ip6r_type);
58 	ND_PRINT(", type=%u", type);
59 	if (type == IPV6_RTHDR_TYPE_0)
60 		ND_PRINT(" [Deprecated]");
61 	ND_PRINT(", segleft=%u", GET_U_1(dp->ip6r_segleft));
62 
63 	switch (type) {
64 	case IPV6_RTHDR_TYPE_0:
65 	case IPV6_RTHDR_TYPE_2:			/* Mobile IPv6 ID-20 */
66 		dp0 = (const struct ip6_rthdr0 *)dp;
67 
68 		if (GET_BE_U_4(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
69 			ND_PRINT(", rsv=0x%0x",
70 			    GET_BE_U_4(dp0->ip6r0_reserved));
71 		}
72 
73 		if (len % 2 == 1) {
74 			ND_PRINT(" (invalid length %u)", len);
75 			goto invalid;
76 		}
77 		len >>= 1;
78 		p = (const u_char *) dp0->ip6r0_addr;
79 		for (i = 0; i < len; i++) {
80 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
81 			p += 16;
82 		}
83 		/*(*/
84 		ND_PRINT(") ");
85 		return((GET_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", GET_U_1(srh->srh_last_ent));
90 
91 		if (GET_U_1(srh->srh_flags) || ndo->ndo_vflag) {
92 			ND_PRINT(", flags=0x%0x",
93 				GET_U_1(srh->srh_flags));
94 		}
95 
96 		ND_PRINT(", tag=%x", GET_BE_U_2(srh->srh_tag));
97 
98 		if (len % 2 == 1) {
99 			ND_PRINT(" (invalid length %u)", len);
100 			goto invalid;
101 		}
102 		len >>= 1;
103 		p  = (const u_char *) srh->srh_segments;
104 		for (i = 0; i < len; i++) {
105 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
106 			p += 16;
107 		}
108 		/*(*/
109 		ND_PRINT(") ");
110 		return((GET_U_1(srh->srh_len) + 1) << 3);
111 		break;
112 	default:
113 		ND_PRINT(" (unknown type)");
114 		goto invalid;
115 	}
116 
117 invalid:
118 	nd_print_invalid(ndo);
119 	return -1;
120 }
121