xref: /openbsd/usr.sbin/tcpdump/print-ip6.c (revision 404b540a)
1 /*	$OpenBSD: print-ip6.c,v 1.10 2007/10/04 18:38:29 canacar Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  */
23 
24 #ifndef lint
25 static const char rcsid[] =
26     "@(#) /master/usr.sbin/tcpdump/tcpdump/print-ip.c,v 2.1 1995/02/03 18:14:45 polk Exp (LBL)";
27 #endif
28 
29 #ifdef INET6
30 
31 #include <sys/param.h>
32 #include <sys/time.h>
33 #include <sys/types.h>
34 #include <sys/socket.h>
35 
36 #include <netinet/in.h>
37 #include <netinet/in_systm.h>
38 #include <netinet/ip.h>
39 #include <netinet/ip_var.h>
40 #include <netinet/udp.h>
41 #include <netinet/udp_var.h>
42 #include <netinet/tcp.h>
43 
44 #include <inttypes.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "interface.h"
51 #include "addrtoname.h"
52 
53 #include <netinet/ip6.h>
54 
55 /*
56  * print an IP6 datagram.
57  */
58 void
59 ip6_print(register const u_char *bp, register int length)
60 {
61 	register const struct ip6_hdr *ip6;
62 	register int hlen;
63 	register int len;
64 	register const u_char *cp;
65 	int nh;
66 	u_int flow;
67 
68 	ip6 = (const struct ip6_hdr *)bp;
69 
70 	/*
71 	 * The IP header is not word aligned, so copy into abuf.
72 	 * This will never happen with BPF.  It does happen with
73 	 * raw packet dumps from -r.
74 	 */
75 	if ((intptr_t)ip6 & (sizeof(long)-1)) {
76 		static u_char *abuf = NULL;
77 		static int didwarn = 0;
78 		int clen = snapend - bp;
79 		if (clen > snaplen)
80 			clen = snaplen;
81 
82 		if (abuf == NULL) {
83 			abuf = (u_char *)malloc(snaplen);
84 			if (abuf == NULL)
85 				error("ip6_print: malloc");
86 		}
87 		memmove((char *)abuf, (char *)ip6, min(length, clen));
88 		snapend = abuf + clen;
89 		packetp = abuf;
90 		ip6 = (struct ip6_hdr *)abuf;
91 		/* We really want libpcap to give us aligned packets */
92 		if (!didwarn) {
93 			warning("compensating for unaligned libpcap packets");
94 			++didwarn;
95 		}
96 	}
97 
98 	if ((u_char *)(ip6 + 1) > snapend) {
99 		printf("[|ip6]");
100 		return;
101 	}
102 	if (length < sizeof (struct ip6_hdr)) {
103 		(void)printf("truncated-ip6 %d", length);
104 		return;
105 	}
106 	if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
107 		(void)printf("bad-ip6-version %u", ip6->ip6_vfc >> 4);
108 		return;
109 	}
110 	hlen = sizeof(struct ip6_hdr);
111 
112 	len = ntohs(ip6->ip6_plen);
113 	if (length < len + hlen)
114 		(void)printf("truncated-ip6 - %d bytes missing!",
115 			len + hlen - length);
116 
117 	cp = (const u_char *)ip6;
118 	nh = ip6->ip6_nxt;
119 	while (cp + hlen < snapend) {
120 		cp += hlen;
121 
122 		if (cp == (u_char *)(ip6 + 1) &&
123 		    nh != IPPROTO_TCP && nh != IPPROTO_UDP &&
124 		    nh != IPPROTO_ESP && nh != IPPROTO_AH) {
125 			(void)printf("%s > %s: ", ip6addr_string(&ip6->ip6_src),
126 				     ip6addr_string(&ip6->ip6_dst));
127 		}
128 
129 		switch (nh) {
130 		case IPPROTO_HOPOPTS:
131 			hlen = hbhopt_print(cp);
132 			nh = *cp;
133 			break;
134 		case IPPROTO_DSTOPTS:
135 			hlen = dstopt_print(cp);
136 			nh = *cp;
137 			break;
138 		case IPPROTO_FRAGMENT:
139 			hlen = frag6_print(cp, (const u_char *)ip6);
140 			if (snapend <= cp + hlen)
141 				goto end;
142 			nh = *cp;
143 			break;
144 		case IPPROTO_ROUTING:
145 			hlen = rt6_print(cp, (const u_char *)ip6);
146 			nh = *cp;
147 			break;
148 		case IPPROTO_TCP:
149 			tcp_print(cp, len + sizeof(struct ip6_hdr) - (cp - bp),
150 				(const u_char *)ip6);
151 			goto end;
152 		case IPPROTO_UDP:
153 			udp_print(cp, len + sizeof(struct ip6_hdr) - (cp - bp),
154 				(const u_char *)ip6);
155 			goto end;
156 		case IPPROTO_ESP:
157 			esp_print(cp, len + sizeof(struct ip6_hdr) - (cp - bp),
158 				(const u_char *)ip6);
159 			goto end;
160 		case IPPROTO_AH:
161 			ah_print(cp, len + sizeof(struct ip6_hdr) - (cp - bp),
162 				(const u_char *)ip6);
163 			goto end;
164 		case IPPROTO_ICMPV6:
165 			icmp6_print(cp, (const u_char *)ip6);
166 			goto end;
167 		case IPPROTO_PIM:
168 			(void)printf("PIM");
169 			pim_print(cp, len);
170 			goto end;
171 #ifndef IPPROTO_OSPF
172 #define IPPROTO_OSPF 89
173 #endif
174 		case IPPROTO_OSPF:
175 			ospf6_print(cp, len);
176 			goto end;
177 		case IPPROTO_IPV6:
178 			ip6_print(cp, len);
179 			goto end;
180 #ifndef IPPROTO_IPV4
181 #define IPPROTO_IPV4	4
182 #endif
183 		case IPPROTO_IPV4:
184 			ip_print(cp, len);
185 			goto end;
186 		case IPPROTO_NONE:
187 			(void)printf("no next header");
188 			goto end;
189 
190 #ifndef IPPROTO_CARP
191 #define IPPROTO_CARP 112
192 #endif
193 		case IPPROTO_CARP:
194 			if (packettype == PT_VRRP)
195 				vrrp_print(cp, len, ip6->ip6_hlim);
196 			else
197 				carp_print(cp, len, ip6->ip6_hlim);
198 			break;
199 
200 		default:
201 			(void)printf("ip-proto-%d %d", ip6->ip6_nxt, len);
202 			goto end;
203 		}
204 		if (hlen == 0)
205 			break;
206 	}
207 
208  end:
209 
210 	flow = ntohl(ip6->ip6_flow);
211 #if 0
212 	/* rfc1883 */
213 	if (flow & 0x0f000000)
214 		(void)printf(" [pri 0x%x]", (flow & 0x0f000000) >> 24);
215 	if (flow & 0x00ffffff)
216 		(void)printf(" [flowlabel 0x%x]", flow & 0x00ffffff);
217 #else
218 	/* RFC 2460 */
219 	if (flow & 0x0ff00000)
220 		(void)printf(" [class 0x%x]", (flow & 0x0ff00000) >> 20);
221 	if (flow & 0x000fffff)
222 		(void)printf(" [flowlabel 0x%x]", flow & 0x000fffff);
223 #endif
224 
225 	if (ip6->ip6_hlim <= 1)
226 		(void)printf(" [hlim %d]", (int)ip6->ip6_hlim);
227 
228 	if (vflag) {
229 		printf(" (");
230 		(void)printf("len %d", len);
231 		if (ip6->ip6_hlim > 1)
232 			(void)printf(", hlim %d", (int)ip6->ip6_hlim);
233 		printf(")");
234 	}
235 }
236 
237 #endif /* INET6 */
238