xref: /freebsd/contrib/tcpdump/print-rt6.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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 "netdissect.h"
31 #include "addrtoname.h"
32 #include "extract.h"
33 
34 #include "ip6.h"
35 
36 int
37 rt6_print(netdissect_options *ndo, const u_char *bp, const u_char *bp2 _U_)
38 {
39 	const struct ip6_rthdr *dp;
40 	const struct ip6_rthdr0 *dp0;
41 	const struct ip6_srh *srh;
42 	u_int i, len, type;
43 	const u_char *p;
44 
45 	ndo->ndo_protocol = "rt6";
46 
47 	nd_print_protocol_caps(ndo);
48 	dp = (const struct ip6_rthdr *)bp;
49 
50 	len = GET_U_1(dp->ip6r_len);
51 	ND_PRINT(" (len=%u", len);	/*)*/
52 	type = GET_U_1(dp->ip6r_type);
53 	ND_PRINT(", type=%u", type);
54 	if (type == IPV6_RTHDR_TYPE_0)
55 		ND_PRINT(" [Deprecated]");
56 	ND_PRINT(", segleft=%u", GET_U_1(dp->ip6r_segleft));
57 
58 	switch (type) {
59 	case IPV6_RTHDR_TYPE_0:
60 	case IPV6_RTHDR_TYPE_2:			/* Mobile IPv6 ID-20 */
61 		dp0 = (const struct ip6_rthdr0 *)dp;
62 
63 		if (GET_BE_U_4(dp0->ip6r0_reserved) || ndo->ndo_vflag) {
64 			ND_PRINT(", rsv=0x%0x",
65 			    GET_BE_U_4(dp0->ip6r0_reserved));
66 		}
67 
68 		if (len % 2 == 1) {
69 			ND_PRINT(" (invalid length %u)", len);
70 			goto invalid;
71 		}
72 		len >>= 1;
73 		p = (const u_char *) dp0->ip6r0_addr;
74 		for (i = 0; i < len; i++) {
75 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
76 			p += 16;
77 		}
78 		/*(*/
79 		ND_PRINT(") ");
80 		return((GET_U_1(dp0->ip6r0_len) + 1) << 3);
81 		break;
82 	case IPV6_RTHDR_TYPE_4:
83 		srh = (const struct ip6_srh *)dp;
84 		ND_PRINT(", last-entry=%u", GET_U_1(srh->srh_last_ent));
85 
86 		if (GET_U_1(srh->srh_flags) || ndo->ndo_vflag) {
87 			ND_PRINT(", flags=0x%0x",
88 				GET_U_1(srh->srh_flags));
89 		}
90 
91 		ND_PRINT(", tag=%x", GET_BE_U_2(srh->srh_tag));
92 
93 		if (len % 2 == 1) {
94 			ND_PRINT(" (invalid length %u)", len);
95 			goto invalid;
96 		}
97 		len >>= 1;
98 		p  = (const u_char *) srh->srh_segments;
99 		for (i = 0; i < len; i++) {
100 			ND_PRINT(", [%u]%s", i, GET_IP6ADDR_STRING(p));
101 			p += 16;
102 		}
103 		/*(*/
104 		ND_PRINT(") ");
105 		return((GET_U_1(srh->srh_len) + 1) << 3);
106 		break;
107 	default:
108 		ND_PRINT(" (unknown type)");
109 		goto invalid;
110 	}
111 
112 invalid:
113 	nd_print_invalid(ndo);
114 	return -1;
115 }
116