xref: /freebsd/contrib/tcpdump/print-dhcp6.c (revision f0a75d274af375d15b97b830966b99a02b7db911)
1 /*
2  * Copyright (C) 1998 and 1999 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  * RFC3315: DHCPv6
31  * supported DHCPv6 options:
32  *  RFC3319,
33  *  RFC3633,
34  *  RFC3646,
35  *  draft-ietf-dhc-dhcpv6-opt-timeconfig-03.txt,
36  *  draft-ietf-dhc-lifetime-00.txt,
37  */
38 
39 #ifndef lint
40 static const char rcsid[] _U_ =
41     "@(#) $Header: /tcpdump/master/tcpdump/print-dhcp6.c,v 1.35 2004/07/06 22:16:03 guy Exp $";
42 #endif
43 
44 #ifdef HAVE_CONFIG_H
45 #include "config.h"
46 #endif
47 
48 #include <tcpdump-stdinc.h>
49 
50 #include <stdio.h>
51 #include <string.h>
52 
53 #include "interface.h"
54 #include "addrtoname.h"
55 #include "extract.h"
56 
57 /* lease duration */
58 #define DHCP6_DURATITION_INFINITE 0xffffffff
59 
60 /* Error Values */
61 #define DH6ERR_FAILURE		16
62 #define DH6ERR_AUTHFAIL		17
63 #define DH6ERR_POORLYFORMED	18
64 #define DH6ERR_UNAVAIL		19
65 #define DH6ERR_OPTUNAVAIL	20
66 
67 /* Message type */
68 #define DH6_SOLICIT	1
69 #define DH6_ADVERTISE	2
70 #define DH6_REQUEST	3
71 #define DH6_CONFIRM	4
72 #define DH6_RENEW	5
73 #define DH6_REBIND	6
74 #define DH6_REPLY	7
75 #define DH6_RELEASE	8
76 #define DH6_DECLINE	9
77 #define DH6_RECONFIGURE	10
78 #define DH6_INFORM_REQ	11
79 #define DH6_RELAY_FORW	12
80 #define DH6_RELAY_REPLY	13
81 
82 /* DHCP6 base packet format */
83 struct dhcp6 {
84 	union {
85 		u_int8_t m;
86 		u_int32_t x;
87 	} dh6_msgtypexid;
88 	/* options follow */
89 };
90 #define dh6_msgtype	dh6_msgtypexid.m
91 #define dh6_xid		dh6_msgtypexid.x
92 #define DH6_XIDMASK	0x00ffffff
93 
94 /* DHCPv6 relay messages */
95 struct dhcp6_relay {
96 	u_int8_t dh6relay_msgtype;
97 	u_int8_t dh6relay_hcnt;
98 	u_int8_t dh6relay_linkaddr[16];	/* XXX: badly aligned */
99 	u_int8_t dh6relay_peeraddr[16];
100 	/* options follow */
101 };
102 
103 /* options */
104 #define DH6OPT_CLIENTID	1
105 #define DH6OPT_SERVERID	2
106 #define DH6OPT_IA_NA 3
107 #define DH6OPT_IA_TMP 4
108 #define DH6OPT_IADDR 5
109 #define DH6OPT_ORO 6
110 #define DH6OPT_PREFERENCE 7
111 #  define DH6OPT_PREF_MAX 255
112 #define DH6OPT_ELAPSED_TIME 8
113 #define DH6OPT_RELAY_MSG 9
114 /*#define DH6OPT_SERVER_MSG 10 deprecated */
115 #define DH6OPT_AUTH 11
116 #  define DH6OPT_AUTHPROTO_DELAYED 2
117 #  define DH6OPT_AUTHPROTO_RECONFIG 3
118 #  define DH6OPT_AUTHALG_HMACMD5 1
119 #  define DH6OPT_AUTHRDM_MONOCOUNTER 0
120 #  define DH6OPT_AUTHRECONFIG_KEY 1
121 #  define DH6OPT_AUTHRECONFIG_HMACMD5 2
122 #define DH6OPT_UNICAST 12
123 #define DH6OPT_STATUS_CODE 13
124 #  define DH6OPT_STCODE_SUCCESS 0
125 #  define DH6OPT_STCODE_UNSPECFAIL 1
126 #  define DH6OPT_STCODE_NOADDRAVAIL 2
127 #  define DH6OPT_STCODE_NOBINDING 3
128 #  define DH6OPT_STCODE_NOTONLINK 4
129 #  define DH6OPT_STCODE_USEMULTICAST 5
130 #  define DH6OPT_STCODE_NOPREFIXAVAIL 6
131 #define DH6OPT_RAPID_COMMIT 14
132 #define DH6OPT_USER_CLASS 15
133 #define DH6OPT_VENDOR_CLASS 16
134 #define DH6OPT_VENDOR_OPTS 17
135 #define DH6OPT_INTERFACE_ID 18
136 #define DH6OPT_RECONF_MSG 19
137 #define DH6OPT_RECONF_ACCEPT 20
138 #define DH6OPT_SIP_SERVER_D 21
139 #define DH6OPT_SIP_SERVER_A 22
140 #define DH6OPT_DNS 23
141 #define DH6OPT_DNSNAME 24
142 #define DH6OPT_IA_PD 25
143 #define DH6OPT_IA_PD_PREFIX 26
144 
145 /*
146  * The old prefix delegation option used in the service specification document
147  * (200206xx version) by NTT Communications.
148  */
149 #define DH6OPT_PREFIX_DELEGATION 30
150 #define DH6OPT_PREFIX_INFORMATION 31
151 #define DH6OPT_PREFIX_REQUEST 32
152 
153 /*
154  * The following one is an unassigned number.
155  * We temporarily use values as of KAME snap 20040322.
156  */
157 #define DH6OPT_NTP_SERVERS 35
158 #define DH6OPT_LIFETIME 36
159 
160 struct dhcp6opt {
161 	u_int16_t dh6opt_type;
162 	u_int16_t dh6opt_len;
163 	/* type-dependent data follows */
164 };
165 
166 struct dhcp6_ia {
167 	u_int16_t dh6opt_ia_type;
168 	u_int16_t dh6opt_ia_len;
169 	u_int32_t dh6opt_ia_iaid;
170 	u_int32_t dh6opt_ia_t1;
171 	u_int32_t dh6opt_ia_t2;
172 };
173 
174 struct dhcp6_ia_prefix {
175 	u_int16_t dh6opt_ia_prefix_type;
176 	u_int16_t dh6opt_ia_prefix_len;
177 	u_int32_t dh6opt_ia_prefix_pltime;
178 	u_int32_t dh6opt_ia_prefix_vltime;
179 	u_int8_t dh6opt_ia_prefix_plen;
180 	struct in6_addr dh6opt_ia_prefix_addr;
181 }  __attribute__ ((__packed__));
182 
183 struct dhcp6_auth {
184 	u_int16_t dh6opt_auth_type;
185 	u_int16_t dh6opt_auth_len;
186 	u_int8_t dh6opt_auth_proto;
187 	u_int8_t dh6opt_auth_alg;
188 	u_int8_t dh6opt_auth_rdm;
189 	u_int8_t dh6opt_auth_rdinfo[8];
190 	/* authentication information follows */
191 } __attribute__ ((__packed__));
192 
193 static const char *
194 dhcp6opt_name(int type)
195 {
196 	static char genstr[sizeof("opt_65535") + 1]; /* XXX thread unsafe */
197 
198 	if (type > 65535)
199 		return "INVALID option";
200 
201 	switch(type) {
202 	case DH6OPT_CLIENTID:
203 		return "client ID";
204 	case DH6OPT_SERVERID:
205 		return "server ID";
206 	case DH6OPT_IA_NA:
207 		return "IA_NA";
208 	case DH6OPT_ORO:
209 		return "option request";
210 	case DH6OPT_PREFERENCE:
211 		return "preference";
212 	case DH6OPT_ELAPSED_TIME:
213 		return "elapsed time";
214 	case DH6OPT_RELAY_MSG:
215 		return "relay message";
216 	case DH6OPT_AUTH:
217 		return "authentication";
218 	case DH6OPT_UNICAST:
219 		return "server unicast";
220 	case DH6OPT_STATUS_CODE:
221 		return "status code";
222 	case DH6OPT_RAPID_COMMIT:
223 		return "rapid commit";
224 	case DH6OPT_USER_CLASS:
225 		return "user class";
226 	case DH6OPT_VENDOR_CLASS:
227 		return "vendor class";
228 	case DH6OPT_VENDOR_OPTS:
229 		return "vendor-specific info";
230 	case DH6OPT_INTERFACE_ID:
231 		return "interface ID";
232 	case DH6OPT_RECONF_MSG:
233 		return "reconfigure message";
234 	case DH6OPT_RECONF_ACCEPT:
235 		return "reconfigure accept";
236 	case DH6OPT_SIP_SERVER_D:
237 		return "SIP servers domain";
238 	case DH6OPT_SIP_SERVER_A:
239 		return "SIP servers address";
240 	case DH6OPT_DNS:
241 		return "DNS";
242 	case DH6OPT_DNSNAME:
243 		return "DNS name";
244 	case DH6OPT_PREFIX_DELEGATION:
245 		return "prefix delegation";
246 	case DH6OPT_PREFIX_INFORMATION:
247 		return "prefix information";
248 	case DH6OPT_IA_PD:
249 		return "IA_PD";
250 	case DH6OPT_IA_PD_PREFIX:
251 		return "IA_PD prefix";
252 	case DH6OPT_NTP_SERVERS:
253 		return "NTP Server";
254 	case DH6OPT_LIFETIME:
255 		return "lifetime";
256 	default:
257 		snprintf(genstr, sizeof(genstr), "opt_%d", type);
258 		return(genstr);
259 	}
260 }
261 
262 static const char *
263 dhcp6stcode(int code)
264 {
265 	static char genstr[sizeof("code255") + 1]; /* XXX thread unsafe */
266 
267 	if (code > 255)
268 		return "INVALID code";
269 
270 	switch(code) {
271 	case DH6OPT_STCODE_SUCCESS:
272 		return "success";
273 	case DH6OPT_STCODE_UNSPECFAIL:
274 		return "unspec failure";
275 	case DH6OPT_STCODE_NOADDRAVAIL:
276 		return "no addresses";
277 	case DH6OPT_STCODE_NOBINDING:
278 		return "no binding";
279 	case DH6OPT_STCODE_NOTONLINK:
280 		return "not on-link";
281 	case DH6OPT_STCODE_USEMULTICAST:
282 		return "use multicast";
283 	case DH6OPT_STCODE_NOPREFIXAVAIL:
284 		return "no prefixes";
285 	default:
286 		snprintf(genstr, sizeof(genstr), "code%d", code);
287 		return(genstr);
288 	}
289 }
290 
291 static void
292 dhcp6opt_print(const u_char *cp, const u_char *ep)
293 {
294 	struct dhcp6opt *dh6o;
295 	u_char *tp;
296 	size_t i;
297 	u_int16_t opttype;
298 	size_t optlen;
299 	u_int16_t val16;
300 	u_int32_t val32;
301 	struct in6_addr addr6;
302 	struct dhcp6_ia ia;
303 	struct dhcp6_ia_prefix ia_prefix;
304 	struct dhcp6_auth authopt;
305 	u_int authinfolen, authrealmlen;
306 
307 	if (cp == ep)
308 		return;
309 	while (cp < ep) {
310 		if (ep < cp + sizeof(*dh6o))
311 			goto trunc;
312 		dh6o = (struct dhcp6opt *)cp;
313 		optlen = EXTRACT_16BITS(&dh6o->dh6opt_len);
314 		if (ep < cp + sizeof(*dh6o) + optlen)
315 			goto trunc;
316 		opttype = EXTRACT_16BITS(&dh6o->dh6opt_type);
317 		printf(" (%s", dhcp6opt_name(opttype));
318 		switch (opttype) {
319 		case DH6OPT_CLIENTID:
320 		case DH6OPT_SERVERID:
321 			if (optlen < 2) {
322 				/*(*/
323 				printf(" ?)");
324 				break;
325 			}
326 			tp = (u_char *)(dh6o + 1);
327 			switch (EXTRACT_16BITS(tp)) {
328 			case 1:
329 				if (optlen >= 2 + 6) {
330 					printf(" hwaddr/time type %u time %u ",
331 					    EXTRACT_16BITS(&tp[2]),
332 					    EXTRACT_32BITS(&tp[4]));
333 					for (i = 8; i < optlen; i++)
334 						printf("%02x", tp[i]);
335 					/*(*/
336 					printf(")");
337 				} else {
338 					/*(*/
339 					printf(" ?)");
340 				}
341 				break;
342 			case 2:
343 				if (optlen >= 2 + 8) {
344 					printf(" vid ");
345 					for (i = 2; i < 2 + 8; i++)
346 						printf("%02x", tp[i]);
347 					/*(*/
348 					printf(")");
349 				} else {
350 					/*(*/
351 					printf(" ?)");
352 				}
353 				break;
354 			case 3:
355 				if (optlen >= 2 + 2) {
356 					printf(" hwaddr type %u ",
357 					    EXTRACT_16BITS(&tp[2]));
358 					for (i = 4; i < optlen; i++)
359 						printf("%02x", tp[i]);
360 					/*(*/
361 					printf(")");
362 				} else {
363 					/*(*/
364 					printf(" ?)");
365 				}
366 				break;
367 			default:
368 				printf(" type %d)", EXTRACT_16BITS(tp));
369 				break;
370 			}
371 			break;
372 		case DH6OPT_ORO:
373 			if (optlen % 2) {
374 				printf(" ?)");
375 				break;
376 			}
377 			tp = (u_char *)(dh6o + 1);
378 			for (i = 0; i < optlen; i += 2) {
379 				u_int16_t opt;
380 
381 				memcpy(&opt, &tp[i], sizeof(opt));
382 				printf(" %s", dhcp6opt_name(ntohs(opt)));
383 			}
384 			printf(")");
385 			break;
386 		case DH6OPT_PREFERENCE:
387 			if (optlen != 1) {
388 				printf(" ?)");
389 				break;
390 			}
391 			printf(" %d)", *((u_char *)(dh6o + 1) + 1));
392 			break;
393 		case DH6OPT_ELAPSED_TIME:
394 			if (optlen != 2) {
395 				printf(" ?)");
396 				break;
397 			}
398 			memcpy(&val16, dh6o + 1, sizeof(val16));
399 			val16 = ntohs(val16);
400 			printf(" %d)", (int)val16);
401 			break;
402 		case DH6OPT_RELAY_MSG:
403 			printf(" (");
404 			dhcp6_print((const u_char *)(dh6o + 1), optlen);
405 			printf(")");
406 			break;
407 		case DH6OPT_AUTH:
408 			if (optlen < sizeof(authopt) - sizeof(*dh6o)) {
409 				printf(" ?)");
410 				break;
411 			}
412 			memcpy(&authopt, dh6o, sizeof(authopt));
413 			switch (authopt.dh6opt_auth_proto) {
414 			case DH6OPT_AUTHPROTO_DELAYED:
415 				printf(" proto: delayed");
416 				break;
417 			case DH6OPT_AUTHPROTO_RECONFIG:
418 				printf(" proto: reconfigure");
419 				break;
420 			default:
421 				printf(" proto: %d",
422 				    authopt.dh6opt_auth_proto);
423 				break;
424 			}
425 			switch (authopt.dh6opt_auth_alg) {
426 			case DH6OPT_AUTHALG_HMACMD5:
427 				/* XXX: may depend on the protocol */
428 				printf(", alg: HMAC-MD5");
429 				break;
430 			default:
431 				printf(", alg: %d", authopt.dh6opt_auth_alg);
432 				break;
433 			}
434 			switch (authopt.dh6opt_auth_rdm) {
435 			case DH6OPT_AUTHRDM_MONOCOUNTER:
436 				printf(", RDM: mono");
437 				break;
438 			default:
439 				printf(", RDM: %d", authopt.dh6opt_auth_rdm);
440 				break;
441 			}
442 			tp = (u_char *)&authopt.dh6opt_auth_rdinfo;
443 			printf(", RD:");
444 			for (i = 0; i < 4; i++, tp += sizeof(val16))
445 				printf(" %04x", EXTRACT_16BITS(tp));
446 
447 			/* protocol dependent part */
448 			tp = (u_char *)dh6o + sizeof(authopt);
449 			authinfolen =
450 			    optlen + sizeof(*dh6o) - sizeof(authopt);
451 			switch (authopt.dh6opt_auth_proto) {
452 			case DH6OPT_AUTHPROTO_DELAYED:
453 				if (authinfolen == 0)
454 					break;
455 				if (authinfolen < 20) {
456 					printf(" ??");
457 					break;
458 				}
459 				authrealmlen = authinfolen - 20;
460 				if (authrealmlen > 0) {
461 					printf(", realm: ");
462 				}
463 				for (i = 0; i < authrealmlen; i++, tp++)
464 					printf("%02x", *tp);
465 				printf(", key ID: %08x", EXTRACT_32BITS(tp));
466 				tp += 4;
467 				printf(", HMAC-MD5:");
468 				for (i = 0; i < 4; i++, tp+= 4)
469 					printf(" %08x", EXTRACT_32BITS(tp));
470 				break;
471 			case DH6OPT_AUTHPROTO_RECONFIG:
472 				if (authinfolen != 17) {
473 					printf(" ??");
474 					break;
475 				}
476 				switch (*tp++) {
477 				case DH6OPT_AUTHRECONFIG_KEY:
478 					printf(" reconfig-key");
479 					break;
480 				case DH6OPT_AUTHRECONFIG_HMACMD5:
481 					printf(" type: HMAC-MD5");
482 					break;
483 				default:
484 					printf(" type: ??");
485 					break;
486 				}
487 				printf(" value:");
488 				for (i = 0; i < 4; i++, tp+= 4)
489 					printf(" %08x", EXTRACT_32BITS(tp));
490 				break;
491 			default:
492 				printf(" ??");
493 				break;
494 			}
495 
496 			printf(")");
497 			break;
498 		case DH6OPT_RAPID_COMMIT: /* nothing todo */
499 			printf(")");
500 			break;
501 		case DH6OPT_INTERFACE_ID:
502 			/*
503 			 * Since we cannot predict the encoding, print hex dump
504 			 * at most 10 characters.
505 			 */
506 			for (i = 0; i < optlen && i < 10; i++)
507 				printf("%02x", ((u_char *)(dh6o + 1))[i]);
508 			break;
509 		case DH6OPT_RECONF_MSG:
510 			tp = (u_char *)(dh6o + 1);
511 			switch (*tp) {
512 			case DH6_RENEW:
513 				printf(" for renew)");
514 				break;
515 			case DH6_INFORM_REQ:
516 				printf(" for inf-req)");
517 				break;
518 			default:
519 				printf(" for ?\?\?(%02x))", *tp);
520 				break;
521 			}
522 			break;
523 		case DH6OPT_RECONF_ACCEPT: /* nothing todo */
524 			printf(")");
525 			break;
526 		case DH6OPT_SIP_SERVER_A:
527 		case DH6OPT_DNS:
528 		case DH6OPT_NTP_SERVERS:
529 			if (optlen % 16) {
530 				printf(" ?)");
531 				break;
532 			}
533 			tp = (u_char *)(dh6o + 1);
534 			for (i = 0; i < optlen; i += 16)
535 				printf(" %s", ip6addr_string(&tp[i]));
536 			printf(")");
537 			break;
538 		case DH6OPT_PREFIX_DELEGATION:
539 			dhcp6opt_print((u_char *)(dh6o + 1),
540 			    (u_char *)(dh6o + 1) + optlen);
541 			printf(")");
542 			break;
543 		case DH6OPT_PREFIX_INFORMATION:
544 			if (optlen % 21)
545 				printf(" ?)");
546 			memcpy(&addr6, (u_char *)(dh6o + 1) + 5,
547 			    sizeof(addr6));
548 			printf(" %s/%d", ip6addr_string(&addr6),
549 			    (int)*((u_char *)(dh6o + 1) + 4));
550 			memcpy(&val32, dh6o + 1, sizeof(val32));
551 			val32 = ntohl(val32);
552 			if (val32 == DHCP6_DURATITION_INFINITE)
553 				printf(" lease-duration: infinite)");
554 			else
555 				printf(" lease-duration: %u)", val32);
556 			break;
557 		case DH6OPT_STATUS_CODE:
558 			if (optlen < 2) {
559 				printf(" ?)");
560 				break;
561 			}
562 			memcpy(&val16, (u_char *)(dh6o + 1), sizeof(val16));
563 			val16 = ntohs(val16);
564 			printf(" %s)", dhcp6stcode(val16));
565 			break;
566 		case DH6OPT_IA_NA:
567 		case DH6OPT_IA_PD:
568 			if (optlen < sizeof(ia) - 4) {
569 				printf(" ?)");
570 				break;
571 			}
572 			memcpy(&ia, (u_char *)dh6o, sizeof(ia));
573 			ia.dh6opt_ia_iaid = ntohl(ia.dh6opt_ia_iaid);
574 			ia.dh6opt_ia_t1 = ntohl(ia.dh6opt_ia_t1);
575 			ia.dh6opt_ia_t2 = ntohl(ia.dh6opt_ia_t2);
576 			printf(" IAID:%lu T1:%lu T2:%lu",
577 			    (unsigned long)ia.dh6opt_ia_iaid,
578 			    (unsigned long)ia.dh6opt_ia_t1,
579 			    (unsigned long)ia.dh6opt_ia_t2);
580 			if (optlen > sizeof(ia) - 4) {
581 				/* there are sub-options */
582 				dhcp6opt_print((u_char *)dh6o + sizeof(ia),
583 				    (u_char *)(dh6o + 1) + optlen);
584 			}
585 			printf(")");
586 			break;
587 		case DH6OPT_IA_PD_PREFIX:
588 			if (optlen < sizeof(ia_prefix) - 4) {
589 				printf(" ?)");
590 				break;
591 			}
592 			memcpy(&ia_prefix, (u_char *)dh6o, sizeof(ia_prefix));
593 			printf(" %s/%d",
594 			    ip6addr_string(&ia_prefix.dh6opt_ia_prefix_addr),
595 			    ia_prefix.dh6opt_ia_prefix_plen);
596 			ia_prefix.dh6opt_ia_prefix_pltime =
597 			    ntohl(ia_prefix.dh6opt_ia_prefix_pltime);
598 			ia_prefix.dh6opt_ia_prefix_vltime =
599 			    ntohl(ia_prefix.dh6opt_ia_prefix_vltime);
600 			printf(" pltime:%lu vltime:%lu",
601 			    (unsigned long)ia_prefix.dh6opt_ia_prefix_pltime,
602 			    (unsigned long)ia_prefix.dh6opt_ia_prefix_vltime);
603 			if (optlen > sizeof(ia_prefix) - 4) {
604 				/* there are sub-options */
605 				dhcp6opt_print((u_char *)dh6o +
606 				    sizeof(ia_prefix),
607 				    (u_char *)(dh6o + 1) + optlen);
608 			}
609 			printf(")");
610 			break;
611 		case DH6OPT_LIFETIME:
612 			if (optlen != 4) {
613 				printf(" ?)");
614 				break;
615 			}
616 			memcpy(&val32, dh6o + 1, sizeof(val32));
617 			val32 = ntohl(val32);
618 			printf(" %d)", (int)val32);
619 			break;
620 		default:
621 			printf(")");
622 			break;
623 		}
624 
625 		cp += sizeof(*dh6o) + optlen;
626 	}
627 	return;
628 
629 trunc:
630 	printf("[|dhcp6ext]");
631 }
632 
633 /*
634  * Print dhcp6 packets
635  */
636 void
637 dhcp6_print(const u_char *cp, u_int length)
638 {
639 	struct dhcp6 *dh6;
640 	struct dhcp6_relay *dh6relay;
641 	const u_char *ep;
642 	u_char *extp;
643 	const char *name;
644 
645 	printf("dhcp6");
646 
647 	ep = (u_char *)snapend;
648 	if (cp + length < ep)
649 		ep = cp + length;
650 
651 	dh6 = (struct dhcp6 *)cp;
652 	dh6relay = (struct dhcp6_relay *)cp;
653 	TCHECK(dh6->dh6_xid);
654 	switch (dh6->dh6_msgtype) {
655 	case DH6_SOLICIT:
656 		name = "solicit";
657 		break;
658 	case DH6_ADVERTISE:
659 		name = "advertise";
660 		break;
661 	case DH6_REQUEST:
662 		name = "request";
663 		break;
664 	case DH6_CONFIRM:
665 		name = "confirm";
666 		break;
667 	case DH6_RENEW:
668 		name = "renew";
669 		break;
670 	case DH6_REBIND:
671 		name = "rebind";
672 		break;
673 	case DH6_REPLY:
674 		name = "reply";
675 		break;
676 	case DH6_RELEASE:
677 		name = "release";
678 		break;
679 	case DH6_DECLINE:
680 		name = "decline";
681 		break;
682 	case DH6_RECONFIGURE:
683 		name = "reconfigure";
684 		break;
685 	case DH6_INFORM_REQ:
686 		name= "inf-req";
687 		break;
688 	case DH6_RELAY_FORW:
689 		name= "relay-fwd";
690 		break;
691 	case DH6_RELAY_REPLY:
692 		name= "relay-reply";
693 		break;
694 	default:
695 		name = NULL;
696 		break;
697 	}
698 
699 	if (!vflag) {
700 		if (name)
701 			printf(" %s", name);
702 		else if (dh6->dh6_msgtype != DH6_RELAY_FORW &&
703 		    dh6->dh6_msgtype != DH6_RELAY_REPLY) {
704 			printf(" msgtype-%u", dh6->dh6_msgtype);
705 		}
706 		return;
707 	}
708 
709 	/* XXX relay agent messages have to be handled differently */
710 
711 	if (name)
712 		printf(" %s (", name);	/*)*/
713 	else
714 		printf(" msgtype-%u (", dh6->dh6_msgtype);	/*)*/
715 	if (dh6->dh6_msgtype != DH6_RELAY_FORW &&
716 	    dh6->dh6_msgtype != DH6_RELAY_REPLY) {
717 		printf("xid=%x", EXTRACT_32BITS(&dh6->dh6_xid) & DH6_XIDMASK);
718 		extp = (u_char *)(dh6 + 1);
719 		dhcp6opt_print(extp, ep);
720 	} else {		/* relay messages */
721 		struct in6_addr addr6;
722 
723 		TCHECK(dh6relay->dh6relay_peeraddr);
724 
725 		memcpy(&addr6, dh6relay->dh6relay_linkaddr, sizeof (addr6));
726 		printf("linkaddr=%s", ip6addr_string(&addr6));
727 
728 		memcpy(&addr6, dh6relay->dh6relay_peeraddr, sizeof (addr6));
729 		printf(" peeraddr=%s", ip6addr_string(&addr6));
730 
731 		dhcp6opt_print((u_char *)(dh6relay + 1), ep);
732 	}
733 	/*(*/
734 	printf(")");
735 	return;
736 
737 trunc:
738 	printf("[|dhcp6]");
739 }
740