1 /*
2  * Copyright (C) 2002 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #ifndef lint
32 __RCSID("$NetBSD: print-mobility.c,v 1.5 2015/03/31 21:59:35 christos Exp $");
33 #endif
34 
35 #define NETDISSECT_REWORKED
36 #ifdef HAVE_CONFIG_H
37 #include "config.h"
38 #endif
39 
40 #ifdef INET6
41 #include <tcpdump-stdinc.h>
42 
43 #include "ip6.h"
44 #include "interface.h"
45 #include "addrtoname.h"
46 #include "extract.h"		/* must come after interface.h */
47 
48 /* Mobility header */
49 struct ip6_mobility {
50 	uint8_t ip6m_pproto;	/* following payload protocol (for PG) */
51 	uint8_t ip6m_len;	/* length in units of 8 octets */
52 	uint8_t ip6m_type;	/* message type */
53 	uint8_t reserved;	/* reserved */
54 	uint16_t ip6m_cksum;	/* sum of IPv6 pseudo-header and MH */
55 	union {
56 		uint16_t	ip6m_un_data16[1]; /* type-specific field */
57 		uint8_t		ip6m_un_data8[2];  /* type-specific field */
58 	} ip6m_dataun;
59 };
60 
61 #define ip6m_data16	ip6m_dataun.ip6m_un_data16
62 #define ip6m_data8	ip6m_dataun.ip6m_un_data8
63 
64 #define IP6M_MINLEN	8
65 
66 /* http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xhtml */
67 
68 /* message type */
69 #define IP6M_BINDING_REQUEST	0	/* Binding Refresh Request */
70 #define IP6M_HOME_TEST_INIT	1	/* Home Test Init */
71 #define IP6M_CAREOF_TEST_INIT	2	/* Care-of Test Init */
72 #define IP6M_HOME_TEST		3	/* Home Test */
73 #define IP6M_CAREOF_TEST	4	/* Care-of Test */
74 #define IP6M_BINDING_UPDATE	5	/* Binding Update */
75 #define IP6M_BINDING_ACK	6	/* Binding Acknowledgement */
76 #define IP6M_BINDING_ERROR	7	/* Binding Error */
77 #define IP6M_MAX		7
78 
79 static const unsigned ip6m_hdrlen[IP6M_MAX + 1] = {
80 	IP6M_MINLEN,      /* IP6M_BINDING_REQUEST  */
81 	IP6M_MINLEN + 8,  /* IP6M_HOME_TEST_INIT   */
82 	IP6M_MINLEN + 8,  /* IP6M_CAREOF_TEST_INIT */
83 	IP6M_MINLEN + 16, /* IP6M_HOME_TEST        */
84 	IP6M_MINLEN + 16, /* IP6M_CAREOF_TEST      */
85 	IP6M_MINLEN + 4,  /* IP6M_BINDING_UPDATE   */
86 	IP6M_MINLEN + 4,  /* IP6M_BINDING_ACK      */
87 	IP6M_MINLEN + 16, /* IP6M_BINDING_ERROR    */
88 };
89 
90 /* XXX: unused */
91 #define IP6MOPT_BU_MINLEN	10
92 #define IP6MOPT_BA_MINLEN	13
93 #define IP6MOPT_BR_MINLEN	2
94 
95 /* Mobility Header Options */
96 #define IP6MOPT_MINLEN		2
97 #define IP6MOPT_PAD1          0x0	/* Pad1 */
98 #define IP6MOPT_PADN          0x1	/* PadN */
99 #define IP6MOPT_REFRESH	      0x2	/* Binding Refresh Advice */
100 #define IP6MOPT_REFRESH_MINLEN  4
101 #define IP6MOPT_ALTCOA        0x3	/* Alternate Care-of Address */
102 #define IP6MOPT_ALTCOA_MINLEN  18
103 #define IP6MOPT_NONCEID       0x4	/* Nonce Indices */
104 #define IP6MOPT_NONCEID_MINLEN  6
105 #define IP6MOPT_AUTH          0x5	/* Binding Authorization Data */
106 #define IP6MOPT_AUTH_MINLEN    12
107 
108 static void
109 mobility_opt_print(netdissect_options *ndo,
110                    const u_char *bp, const unsigned len)
111 {
112 	unsigned i, optlen;
113 
114 	for (i = 0; i < len; i += optlen) {
115 		ND_TCHECK(bp[i]);
116 		if (bp[i] == IP6MOPT_PAD1)
117 			optlen = 1;
118 		else {
119 			if (i + 1 < len) {
120 				ND_TCHECK(bp[i + 1]);
121 				optlen = bp[i + 1] + 2;
122 			}
123 			else
124 				goto trunc;
125 		}
126 		if (i + optlen > len)
127 			goto trunc;
128 		ND_TCHECK(bp[i + optlen]);
129 
130 		switch (bp[i]) {
131 		case IP6MOPT_PAD1:
132 			ND_PRINT((ndo, "(pad1)"));
133 			break;
134 		case IP6MOPT_PADN:
135 			if (len - i < IP6MOPT_MINLEN) {
136 				ND_PRINT((ndo, "(padn: trunc)"));
137 				goto trunc;
138 			}
139 			ND_PRINT((ndo, "(padn)"));
140 			break;
141 		case IP6MOPT_REFRESH:
142 			if (len - i < IP6MOPT_REFRESH_MINLEN) {
143 				ND_PRINT((ndo, "(refresh: trunc)"));
144 				goto trunc;
145 			}
146 			/* units of 4 secs */
147 			ND_PRINT((ndo, "(refresh: %u)",
148 				EXTRACT_16BITS(&bp[i+2]) << 2));
149 			break;
150 		case IP6MOPT_ALTCOA:
151 			if (len - i < IP6MOPT_ALTCOA_MINLEN) {
152 				ND_PRINT((ndo, "(altcoa: trunc)"));
153 				goto trunc;
154 			}
155 			ND_PRINT((ndo, "(alt-CoA: %s)", ip6addr_string(ndo, &bp[i+2])));
156 			break;
157 		case IP6MOPT_NONCEID:
158 			if (len - i < IP6MOPT_NONCEID_MINLEN) {
159 				ND_PRINT((ndo, "(ni: trunc)"));
160 				goto trunc;
161 			}
162 			ND_PRINT((ndo, "(ni: ho=0x%04x co=0x%04x)",
163 				EXTRACT_16BITS(&bp[i+2]),
164 				EXTRACT_16BITS(&bp[i+4])));
165 			break;
166 		case IP6MOPT_AUTH:
167 			if (len - i < IP6MOPT_AUTH_MINLEN) {
168 				ND_PRINT((ndo, "(auth: trunc)"));
169 				goto trunc;
170 			}
171 			ND_PRINT((ndo, "(auth)"));
172 			break;
173 		default:
174 			if (len - i < IP6MOPT_MINLEN) {
175 				ND_PRINT((ndo, "(sopt_type %u: trunc)", bp[i]));
176 				goto trunc;
177 			}
178 			ND_PRINT((ndo, "(type-0x%02x: len=%u)", bp[i], bp[i + 1]));
179 			break;
180 		}
181 	}
182 	return;
183 
184 trunc:
185 	ND_PRINT((ndo, "[trunc] "));
186 }
187 
188 /*
189  * Mobility Header
190  */
191 int
192 mobility_print(netdissect_options *ndo,
193                const u_char *bp, const u_char *bp2 _U_)
194 {
195 	const struct ip6_mobility *mh;
196 	const u_char *ep;
197 	unsigned mhlen, hlen;
198 	uint8_t type;
199 
200 	mh = (struct ip6_mobility *)bp;
201 
202 	/* 'ep' points to the end of available data. */
203 	ep = ndo->ndo_snapend;
204 
205 	if (!ND_TTEST(mh->ip6m_len)) {
206 		/*
207 		 * There's not enough captured data to include the
208 		 * mobility header length.
209 		 *
210 		 * Our caller expects us to return the length, however,
211 		 * so return a value that will run to the end of the
212 		 * captured data.
213 		 *
214 		 * XXX - "ip6_print()" doesn't do anything with the
215 		 * returned length, however, as it breaks out of the
216 		 * header-processing loop.
217 		 */
218 		mhlen = ep - bp;
219 		goto trunc;
220 	}
221 	mhlen = (mh->ip6m_len + 1) << 3;
222 
223 	/* XXX ip6m_cksum */
224 
225 	ND_TCHECK(mh->ip6m_type);
226 	type = mh->ip6m_type;
227 	if (type <= IP6M_MAX && mhlen < ip6m_hdrlen[type]) {
228 		ND_PRINT((ndo, "(header length %u is too small for type %u)", mhlen, type));
229 		goto trunc;
230 	}
231 	switch (type) {
232 	case IP6M_BINDING_REQUEST:
233 		ND_PRINT((ndo, "mobility: BRR"));
234 		hlen = IP6M_MINLEN;
235 		break;
236 	case IP6M_HOME_TEST_INIT:
237 	case IP6M_CAREOF_TEST_INIT:
238 		ND_PRINT((ndo, "mobility: %soTI",
239 			type == IP6M_HOME_TEST_INIT ? "H" : "C"));
240 		hlen = IP6M_MINLEN;
241     		if (ndo->ndo_vflag) {
242 			ND_TCHECK2(*mh, hlen + 8);
243 			ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
244 			       type == IP6M_HOME_TEST_INIT ? "Home" : "Care-of",
245 			       EXTRACT_32BITS(&bp[hlen]),
246 			       EXTRACT_32BITS(&bp[hlen + 4])));
247 		}
248 		hlen += 8;
249 		break;
250 	case IP6M_HOME_TEST:
251 	case IP6M_CAREOF_TEST:
252 		ND_PRINT((ndo, "mobility: %soT",
253 			type == IP6M_HOME_TEST ? "H" : "C"));
254 		ND_TCHECK(mh->ip6m_data16[0]);
255 		ND_PRINT((ndo, " nonce id=0x%x", EXTRACT_16BITS(&mh->ip6m_data16[0])));
256 		hlen = IP6M_MINLEN;
257     		if (ndo->ndo_vflag) {
258 			ND_TCHECK2(*mh, hlen + 8);
259 			ND_PRINT((ndo, " %s Init Cookie=%08x:%08x",
260 			       type == IP6M_HOME_TEST ? "Home" : "Care-of",
261 			       EXTRACT_32BITS(&bp[hlen]),
262 			       EXTRACT_32BITS(&bp[hlen + 4])));
263 		}
264 		hlen += 8;
265     		if (ndo->ndo_vflag) {
266 			ND_TCHECK2(*mh, hlen + 8);
267 			ND_PRINT((ndo, " %s Keygen Token=%08x:%08x",
268 			       type == IP6M_HOME_TEST ? "Home" : "Care-of",
269 			       EXTRACT_32BITS(&bp[hlen]),
270 			       EXTRACT_32BITS(&bp[hlen + 4])));
271 		}
272 		hlen += 8;
273 		break;
274 	case IP6M_BINDING_UPDATE:
275 		ND_PRINT((ndo, "mobility: BU"));
276 		ND_TCHECK(mh->ip6m_data16[0]);
277 		ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&mh->ip6m_data16[0])));
278 		hlen = IP6M_MINLEN;
279 		ND_TCHECK2(*mh, hlen + 1);
280 		if (bp[hlen] & 0xf0)
281 			ND_PRINT((ndo, " "));
282 		if (bp[hlen] & 0x80)
283 			ND_PRINT((ndo, "A"));
284 		if (bp[hlen] & 0x40)
285 			ND_PRINT((ndo, "H"));
286 		if (bp[hlen] & 0x20)
287 			ND_PRINT((ndo, "L"));
288 		if (bp[hlen] & 0x10)
289 			ND_PRINT((ndo, "K"));
290 		/* Reserved (4bits) */
291 		hlen += 1;
292 		/* Reserved (8bits) */
293 		hlen += 1;
294 		ND_TCHECK2(*mh, hlen + 2);
295 		/* units of 4 secs */
296 		ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
297 		hlen += 2;
298 		break;
299 	case IP6M_BINDING_ACK:
300 		ND_PRINT((ndo, "mobility: BA"));
301 		ND_TCHECK(mh->ip6m_data8[0]);
302 		ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
303 		if (mh->ip6m_data8[1] & 0x80)
304 			ND_PRINT((ndo, " K"));
305 		/* Reserved (7bits) */
306 		hlen = IP6M_MINLEN;
307 		ND_TCHECK2(*mh, hlen + 2);
308 		ND_PRINT((ndo, " seq#=%u", EXTRACT_16BITS(&bp[hlen])));
309 		hlen += 2;
310 		ND_TCHECK2(*mh, hlen + 2);
311 		/* units of 4 secs */
312 		ND_PRINT((ndo, " lifetime=%u", EXTRACT_16BITS(&bp[hlen]) << 2));
313 		hlen += 2;
314 		break;
315 	case IP6M_BINDING_ERROR:
316 		ND_PRINT((ndo, "mobility: BE"));
317 		ND_TCHECK(mh->ip6m_data8[0]);
318 		ND_PRINT((ndo, " status=%u", mh->ip6m_data8[0]));
319 		/* Reserved */
320 		hlen = IP6M_MINLEN;
321 		ND_TCHECK2(*mh, hlen + 16);
322 		ND_PRINT((ndo, " homeaddr %s", ip6addr_string(ndo, &bp[hlen])));
323 		hlen += 16;
324 		break;
325 	default:
326 		ND_PRINT((ndo, "mobility: type-#%u len=%u", type, mh->ip6m_len));
327 		return(mhlen);
328 		break;
329 	}
330     	if (ndo->ndo_vflag)
331 		mobility_opt_print(ndo, &bp[hlen], mhlen - hlen);
332 
333 	return(mhlen);
334 
335  trunc:
336 	ND_PRINT((ndo, "[|MOBILITY]"));
337 	return(mhlen);
338 }
339 #endif /* INET6 */
340