1 /*
2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 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 #define NETDISSECT_REWORKED
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26
27 #include <tcpdump-stdinc.h>
28
29 #include <string.h>
30
31 #include "interface.h"
32 #include "addrtoname.h"
33 #include "extract.h"
34
35 #ifdef INET6
36
37 #include "ip6.h"
38 #include "ipproto.h"
39
40 /*
41 * Compute a V6-style checksum by building a pseudoheader.
42 */
43 int
nextproto6_cksum(const struct ip6_hdr * ip6,const uint8_t * data,u_int len,u_int covlen,u_int next_proto)44 nextproto6_cksum(const struct ip6_hdr *ip6, const uint8_t *data,
45 u_int len, u_int covlen, u_int next_proto)
46 {
47 struct {
48 struct in6_addr ph_src;
49 struct in6_addr ph_dst;
50 uint32_t ph_len;
51 uint8_t ph_zero[3];
52 uint8_t ph_nxt;
53 } ph;
54 struct cksum_vec vec[2];
55
56 /* pseudo-header */
57 memset(&ph, 0, sizeof(ph));
58 UNALIGNED_MEMCPY(&ph.ph_src, &ip6->ip6_src, sizeof (struct in6_addr));
59 UNALIGNED_MEMCPY(&ph.ph_dst, &ip6->ip6_dst, sizeof (struct in6_addr));
60 ph.ph_len = htonl(len);
61 ph.ph_nxt = next_proto;
62
63 vec[0].ptr = (const uint8_t *)(void *)&ph;
64 vec[0].len = sizeof(ph);
65 vec[1].ptr = data;
66 vec[1].len = covlen;
67
68 return in_cksum(vec, 2);
69 }
70
71 /*
72 * print an IP6 datagram.
73 */
74 void
ip6_print(netdissect_options * ndo,const u_char * bp,u_int length)75 ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
76 {
77 register const struct ip6_hdr *ip6;
78 register int advance;
79 u_int len;
80 const u_char *ipend;
81 register const u_char *cp;
82 register u_int payload_len;
83 int nh;
84 int fragmented = 0;
85 u_int flow;
86
87 ip6 = (const struct ip6_hdr *)bp;
88
89 ND_TCHECK(*ip6);
90 if (length < sizeof (struct ip6_hdr)) {
91 ND_PRINT((ndo, "truncated-ip6 %u", length));
92 return;
93 }
94
95 if (!ndo->ndo_eflag)
96 ND_PRINT((ndo, "IP6 "));
97
98 if (IP6_VERSION(ip6) != 6) {
99 ND_PRINT((ndo,"version error: %u != 6", IP6_VERSION(ip6)));
100 return;
101 }
102
103 payload_len = EXTRACT_16BITS(&ip6->ip6_plen);
104 len = payload_len + sizeof(struct ip6_hdr);
105 if (length < len)
106 ND_PRINT((ndo, "truncated-ip6 - %u bytes missing!",
107 len - length));
108
109 if (ndo->ndo_vflag) {
110 flow = EXTRACT_32BITS(&ip6->ip6_flow);
111 ND_PRINT((ndo, "("));
112 #if 0
113 /* rfc1883 */
114 if (flow & 0x0f000000)
115 ND_PRINT((ndo, "pri 0x%02x, ", (flow & 0x0f000000) >> 24));
116 if (flow & 0x00ffffff)
117 ND_PRINT((ndo, "flowlabel 0x%06x, ", flow & 0x00ffffff));
118 #else
119 /* RFC 2460 */
120 if (flow & 0x0ff00000)
121 ND_PRINT((ndo, "class 0x%02x, ", (flow & 0x0ff00000) >> 20));
122 if (flow & 0x000fffff)
123 ND_PRINT((ndo, "flowlabel 0x%05x, ", flow & 0x000fffff));
124 #endif
125
126 ND_PRINT((ndo, "hlim %u, next-header %s (%u) payload length: %u) ",
127 ip6->ip6_hlim,
128 tok2str(ipproto_values,"unknown",ip6->ip6_nxt),
129 ip6->ip6_nxt,
130 payload_len));
131 }
132
133 /*
134 * Cut off the snapshot length to the end of the IP payload.
135 */
136 ipend = bp + len;
137 if (ipend < ndo->ndo_snapend)
138 ndo->ndo_snapend = ipend;
139
140 cp = (const u_char *)ip6;
141 advance = sizeof(struct ip6_hdr);
142 nh = ip6->ip6_nxt;
143 while (cp < ndo->ndo_snapend && advance > 0) {
144 cp += advance;
145 len -= advance;
146
147 if (cp == (const u_char *)(ip6 + 1) &&
148 nh != IPPROTO_TCP && nh != IPPROTO_UDP &&
149 nh != IPPROTO_DCCP && nh != IPPROTO_SCTP) {
150 ND_PRINT((ndo, "%s > %s: ", ip6addr_string(ndo, &ip6->ip6_src),
151 ip6addr_string(ndo, &ip6->ip6_dst)));
152 }
153
154 switch (nh) {
155 case IPPROTO_HOPOPTS:
156 advance = hbhopt_print(ndo, cp);
157 nh = *cp;
158 break;
159 case IPPROTO_DSTOPTS:
160 advance = dstopt_print(ndo, cp);
161 nh = *cp;
162 break;
163 case IPPROTO_FRAGMENT:
164 advance = frag6_print(ndo, cp, (const u_char *)ip6);
165 if (ndo->ndo_snapend <= cp + advance)
166 return;
167 nh = *cp;
168 fragmented = 1;
169 break;
170
171 case IPPROTO_MOBILITY_OLD:
172 case IPPROTO_MOBILITY:
173 /*
174 * XXX - we don't use "advance"; the current
175 * "Mobility Support in IPv6" draft
176 * (draft-ietf-mobileip-ipv6-24) says that
177 * the next header field in a mobility header
178 * should be IPPROTO_NONE, but speaks of
179 * the possiblity of a future extension in
180 * which payload can be piggybacked atop a
181 * mobility header.
182 */
183 advance = mobility_print(ndo, cp, (const u_char *)ip6);
184 nh = *cp;
185 return;
186 case IPPROTO_ROUTING:
187 advance = rt6_print(ndo, cp, (const u_char *)ip6);
188 nh = *cp;
189 break;
190 case IPPROTO_SCTP:
191 sctp_print(ndo, cp, (const u_char *)ip6, len);
192 return;
193 case IPPROTO_DCCP:
194 dccp_print(ndo, cp, (const u_char *)ip6, len);
195 return;
196 case IPPROTO_TCP:
197 tcp_print(ndo, cp, len, (const u_char *)ip6, fragmented);
198 return;
199 case IPPROTO_UDP:
200 udp_print(ndo, cp, len, (const u_char *)ip6, fragmented);
201 return;
202 case IPPROTO_ICMPV6:
203 icmp6_print(ndo, cp, len, (const u_char *)ip6, fragmented);
204 return;
205 case IPPROTO_AH:
206 advance = ah_print(ndo, cp);
207 nh = *cp;
208 break;
209 case IPPROTO_ESP:
210 {
211 int enh, padlen;
212 advance = esp_print(ndo, cp, len, (const u_char *)ip6, &enh, &padlen);
213 nh = enh & 0xff;
214 len -= padlen;
215 break;
216 }
217 case IPPROTO_IPCOMP:
218 {
219 int enh;
220 advance = ipcomp_print(ndo, cp, &enh);
221 nh = enh & 0xff;
222 break;
223 }
224
225 case IPPROTO_PIM:
226 pim_print(ndo, cp, len, nextproto6_cksum(ip6, cp, len, len,
227 IPPROTO_PIM));
228 return;
229
230 case IPPROTO_OSPF:
231 ospf6_print(ndo, cp, len);
232 return;
233
234 case IPPROTO_IPV6:
235 ip6_print(ndo, cp, len);
236 return;
237
238 case IPPROTO_IPV4:
239 ip_print(ndo, cp, len);
240 return;
241
242 case IPPROTO_PGM:
243 pgm_print(ndo, cp, len, (const u_char *)ip6);
244 return;
245
246 case IPPROTO_GRE:
247 gre_print(ndo, cp, len);
248 return;
249
250 case IPPROTO_RSVP:
251 rsvp_print(ndo, cp, len);
252 return;
253
254 case IPPROTO_NONE:
255 ND_PRINT((ndo, "no next header"));
256 return;
257
258 default:
259 ND_PRINT((ndo, "ip-proto-%d %d", nh, len));
260 return;
261 }
262 }
263
264 return;
265 trunc:
266 ND_PRINT((ndo, "[|ip6]"));
267 }
268
269 #else /* INET6 */
270
271 void
ip6_print(netdissect_options * ndo,const u_char * bp _U_,u_int length)272 ip6_print(netdissect_options *ndo, const u_char *bp _U_, u_int length)
273 {
274 ND_PRINT((ndo, "IP6, length: %u (printing not supported)", length));
275 }
276
277 #endif /* INET6 */
278