xref: /netbsd-src/external/bsd/tcpdump/dist/print-rt6.c (revision 3117ece4fc4a4ca4489ba793710b60b0d26bab6c)
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 1.9 2024/09/02 16:15:32 christos Exp $");
25 #endif
26 
27 /* \summary: IPv6 routing header printer */
28 
29 #include <config.h>
30 
31 #include "netdissect-stdinc.h"
32 
33 #include "netdissect.h"
34 #include "addrtoname.h"
35 #include "extract.h"
36 
37 #include "ip6.h"
38 
39 int
40 rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
41 {
42 	const struct ip6_rthdr *dp;
43 	const struct ip6_rthdr0 *dp0;
44 	const struct ip6_srh *srh;
45 	u_int i, len, type;
46 	const u_char *p;
47 
48 	ndo->ndo_protocol = "rt6";
49 
50 	nd_print_protocol_caps(ndo);
51 	dp = (const struct ip6_rthdr *)bp;
52 
53 	len = GET_U_1(dp->ip6r_len);
54 	ND_PRINT(" (len=%u", len);	/*)*/
55 	type = GET_U_1(dp->ip6r_type);
56 	ND_PRINT(", type=%u", type);
57 	if (type == IPV6_RTHDR_TYPE_0)
58 		ND_PRINT(" [Deprecated]");
59 	ND_PRINT(", segleft=%u", GET_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 		if (GET_BE_U_4(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
67 			ND_PRINT(", rsv=0x%0x",
68 			    GET_BE_U_4(dp0->ip6r0_reserved));
69 		}
70 
71 		if (len % 2 == 1) {
72 			ND_PRINT(" [length %u]", len);
73 			goto invalid;
74 		}
75 		len >>= 1;
76 		p = (const u_char *) dp0->ip6r0_addr;
77 		for (i = 0; i < len; i++) {
78 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
79 			p += 16;
80 		}
81 		/*(*/
82 		ND_PRINT(") ");
83 		return((GET_U_1(dp0->ip6r0_len) + 1) << 3);
84 		break;
85 	case IPV6_RTHDR_TYPE_4:
86 		srh = (const struct ip6_srh *)dp;
87 		ND_PRINT(", last-entry=%u", GET_U_1(srh->srh_last_ent));
88 
89 		if (GET_U_1(srh->srh_flags) || ndo->ndo_vflag) {
90 			ND_PRINT(", flags=0x%0x",
91 				GET_U_1(srh->srh_flags));
92 		}
93 
94 		ND_PRINT(", tag=%x", GET_BE_U_2(srh->srh_tag));
95 
96 		if (len % 2 == 1) {
97 			ND_PRINT(" (invalid length %u)", len);
98 			goto invalid;
99 		}
100 		len >>= 1;
101 		p  = (const u_char *) srh->srh_segments;
102 		for (i = 0; i < len; i++) {
103 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
104 			p += 16;
105 		}
106 		/*(*/
107 		ND_PRINT(") ");
108 		return((GET_U_1(srh->srh_len) + 1) << 3);
109 		break;
110 	default:
111 		ND_PRINT(" (unknown type)");
112 		goto invalid;
113 	}
114 
115 invalid:
116 	nd_print_invalid(ndo);
117 	return -1;
118 }
119