xref: /netbsd-src/external/bsd/tcpdump/dist/print-dhcp6.c (revision 0e2e28bced52bda3788c857106bde6c44d2df3b8)
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 /* \summary: IPv6 DHCP printer */
31 
32 /*
33  * RFC3315: DHCPv6
34  * supported DHCPv6 options:
35  *  RFC3319: Session Initiation Protocol (SIP) Servers options,
36  *  RFC3633: IPv6 Prefix options,
37  *  RFC3646: DNS Configuration options,
38  *  RFC3898: Network Information Service (NIS) Configuration options,
39  *  RFC4075: Simple Network Time Protocol (SNTP) Configuration option,
40  *  RFC4242: Information Refresh Time option,
41  *  RFC4280: Broadcast and Multicast Control Servers options,
42  *  RFC5908: Network Time Protocol (NTP) Server Option for DHCPv6
43  *  RFC6334: Dual-Stack Lite option,
44  */
45 
46 #include <sys/cdefs.h>
47 #ifndef lint
48 __RCSID("$NetBSD: print-dhcp6.c,v 1.9 2023/08/17 20:19:40 christos Exp $");
49 #endif
50 
51 #ifdef HAVE_CONFIG_H
52 #include <config.h>
53 #endif
54 
55 #include "netdissect-stdinc.h"
56 
57 #include "netdissect.h"
58 #include "addrtoname.h"
59 #include "extract.h"
60 
61 /* lease duration */
62 #define DHCP6_DURATION_INFINITE 0xffffffff
63 
64 /* Error Values */
65 #define DH6ERR_FAILURE		16
66 #define DH6ERR_AUTHFAIL		17
67 #define DH6ERR_POORLYFORMED	18
68 #define DH6ERR_UNAVAIL		19
69 #define DH6ERR_OPTUNAVAIL	20
70 
71 /* Message type */
72 #define DH6_SOLICIT	1
73 #define DH6_ADVERTISE	2
74 #define DH6_REQUEST	3
75 #define DH6_CONFIRM	4
76 #define DH6_RENEW	5
77 #define DH6_REBIND	6
78 #define DH6_REPLY	7
79 #define DH6_RELEASE	8
80 #define DH6_DECLINE	9
81 #define DH6_RECONFIGURE	10
82 #define DH6_INFORM_REQ	11
83 #define DH6_RELAY_FORW	12
84 #define DH6_RELAY_REPLY	13
85 #define DH6_LEASEQUERY	14
86 #define DH6_LQ_REPLY	15
87 
88 static const struct tok dh6_msgtype_str[] = {
89 	{ DH6_SOLICIT,     "solicit"          },
90 	{ DH6_ADVERTISE,   "advertise"        },
91 	{ DH6_REQUEST,     "request"          },
92 	{ DH6_CONFIRM,     "confirm"          },
93 	{ DH6_RENEW,       "renew"            },
94 	{ DH6_REBIND,      "rebind"           },
95 	{ DH6_REPLY,       "reply"            },
96 	{ DH6_RELEASE,     "release"          },
97 	{ DH6_DECLINE,     "decline"          },
98 	{ DH6_RECONFIGURE, "reconfigure"      },
99 	{ DH6_INFORM_REQ,  "inf-req"          },
100 	{ DH6_RELAY_FORW,  "relay-fwd"        },
101 	{ DH6_RELAY_REPLY, "relay-reply"      },
102 	{ DH6_LEASEQUERY,  "leasequery"       },
103 	{ DH6_LQ_REPLY,    "leasequery-reply" },
104 	{ 0, NULL }
105 };
106 
107 /* DHCP6 base packet format */
108 struct dhcp6 {
109 	union {
110 		nd_uint8_t msgtype;
111 		nd_uint32_t xid;
112 	} dh6_msgtypexid;
113 	/* options follow */
114 };
115 #define DH6_XIDMASK	0x00ffffff
116 
117 /* DHCPv6 relay messages */
118 struct dhcp6_relay {
119 	nd_uint8_t dh6relay_msgtype;
120 	nd_uint8_t dh6relay_hcnt;
121 	nd_ipv6    dh6relay_linkaddr;	/* XXX: badly aligned */
122 	nd_ipv6    dh6relay_peeraddr;
123 	/* options follow */
124 };
125 
126 /* options */
127 #define DH6OPT_CLIENTID	1
128 #define DH6OPT_SERVERID	2
129 #define DH6OPT_IA_NA 3
130 #define DH6OPT_IA_TA 4
131 #define DH6OPT_IA_ADDR 5
132 #define DH6OPT_ORO 6
133 #define DH6OPT_PREFERENCE 7
134 #  define DH6OPT_PREF_MAX 255
135 #define DH6OPT_ELAPSED_TIME 8
136 #define DH6OPT_RELAY_MSG 9
137 /*#define DH6OPT_SERVER_MSG 10 deprecated */
138 #define DH6OPT_AUTH 11
139 #  define DH6OPT_AUTHPROTO_DELAYED 2
140 #  define DH6OPT_AUTHPROTO_RECONFIG 3
141 #  define DH6OPT_AUTHALG_HMACMD5 1
142 #  define DH6OPT_AUTHRDM_MONOCOUNTER 0
143 #  define DH6OPT_AUTHRECONFIG_KEY 1
144 #  define DH6OPT_AUTHRECONFIG_HMACMD5 2
145 #define DH6OPT_UNICAST 12
146 #define DH6OPT_STATUS_CODE 13
147 #  define DH6OPT_STCODE_SUCCESS 0
148 #  define DH6OPT_STCODE_UNSPECFAIL 1
149 #  define DH6OPT_STCODE_NOADDRAVAIL 2
150 #  define DH6OPT_STCODE_NOBINDING 3
151 #  define DH6OPT_STCODE_NOTONLINK 4
152 #  define DH6OPT_STCODE_USEMULTICAST 5
153 #  define DH6OPT_STCODE_NOPREFIXAVAIL 6
154 #  define DH6OPT_STCODE_UNKNOWNQUERYTYPE 7
155 #  define DH6OPT_STCODE_MALFORMEDQUERY 8
156 #  define DH6OPT_STCODE_NOTCONFIGURED 9
157 #  define DH6OPT_STCODE_NOTALLOWED 10
158 #define DH6OPT_RAPID_COMMIT 14
159 #define DH6OPT_USER_CLASS 15
160 #define DH6OPT_VENDOR_CLASS 16
161 #define DH6OPT_VENDOR_OPTS 17
162 #define DH6OPT_INTERFACE_ID 18
163 #define DH6OPT_RECONF_MSG 19
164 #define DH6OPT_RECONF_ACCEPT 20
165 #define DH6OPT_SIP_SERVER_D 21
166 #define DH6OPT_SIP_SERVER_A 22
167 #define DH6OPT_DNS_SERVERS 23
168 #define DH6OPT_DOMAIN_LIST 24
169 #define DH6OPT_IA_PD 25
170 #define DH6OPT_IA_PD_PREFIX 26
171 #define DH6OPT_NIS_SERVERS 27
172 #define DH6OPT_NISP_SERVERS 28
173 #define DH6OPT_NIS_NAME 29
174 #define DH6OPT_NISP_NAME 30
175 #define DH6OPT_SNTP_SERVERS 31
176 #define DH6OPT_LIFETIME 32
177 #define DH6OPT_BCMCS_SERVER_D 33
178 #define DH6OPT_BCMCS_SERVER_A 34
179 #define DH6OPT_GEOCONF_CIVIC 36
180 #define DH6OPT_REMOTE_ID 37
181 #define DH6OPT_SUBSCRIBER_ID 38
182 #define DH6OPT_CLIENT_FQDN 39
183 #define DH6OPT_PANA_AGENT 40
184 #define DH6OPT_NEW_POSIX_TIMEZONE 41
185 #define DH6OPT_NEW_TZDB_TIMEZONE 42
186 #define DH6OPT_ERO 43
187 #define DH6OPT_LQ_QUERY 44
188 #define DH6OPT_CLIENT_DATA 45
189 #define DH6OPT_CLT_TIME 46
190 #define DH6OPT_LQ_RELAY_DATA 47
191 #define DH6OPT_LQ_CLIENT_LINK 48
192 #define DH6OPT_NTP_SERVER 56
193 #  define DH6OPT_NTP_SUBOPTION_SRV_ADDR 1
194 #  define DH6OPT_NTP_SUBOPTION_MC_ADDR 2
195 #  define DH6OPT_NTP_SUBOPTION_SRV_FQDN 3
196 #define DH6OPT_AFTR_NAME 64
197 #define DH6OPT_MUDURL 112
198 
199 static const struct tok dh6opt_str[] = {
200 	{ DH6OPT_CLIENTID,           "client-ID"            },
201 	{ DH6OPT_SERVERID,           "server-ID"            },
202 	{ DH6OPT_IA_NA,              "IA_NA"                },
203 	{ DH6OPT_IA_TA,              "IA_TA"                },
204 	{ DH6OPT_IA_ADDR,            "IA_ADDR"              },
205 	{ DH6OPT_ORO,                "option-request"       },
206 	{ DH6OPT_PREFERENCE,         "preference"           },
207 	{ DH6OPT_ELAPSED_TIME,       "elapsed-time"         },
208 	{ DH6OPT_RELAY_MSG,          "relay-message"        },
209 	{ DH6OPT_AUTH,               "authentication"       },
210 	{ DH6OPT_UNICAST,            "server-unicast"       },
211 	{ DH6OPT_STATUS_CODE,        "status-code"          },
212 	{ DH6OPT_RAPID_COMMIT,       "rapid-commit"         },
213 	{ DH6OPT_USER_CLASS,         "user-class"           },
214 	{ DH6OPT_VENDOR_CLASS,       "vendor-class"         },
215 	{ DH6OPT_VENDOR_OPTS,        "vendor-specific-info" },
216 	{ DH6OPT_INTERFACE_ID,       "interface-ID"         },
217 	{ DH6OPT_RECONF_MSG,         "reconfigure-message"  },
218 	{ DH6OPT_RECONF_ACCEPT,      "reconfigure-accept"   },
219 	{ DH6OPT_SIP_SERVER_D,       "SIP-servers-domain"   },
220 	{ DH6OPT_SIP_SERVER_A,       "SIP-servers-address"  },
221 	{ DH6OPT_DNS_SERVERS,        "DNS-server"           },
222 	{ DH6OPT_DOMAIN_LIST,        "DNS-search-list"      },
223 	{ DH6OPT_IA_PD,              "IA_PD"                },
224 	{ DH6OPT_IA_PD_PREFIX,       "IA_PD-prefix"         },
225 	{ DH6OPT_SNTP_SERVERS,       "SNTP-servers"         },
226 	{ DH6OPT_LIFETIME,           "lifetime"             },
227 	{ DH6OPT_NIS_SERVERS,        "NIS-server"           },
228 	{ DH6OPT_NISP_SERVERS,       "NIS+-server"          },
229 	{ DH6OPT_NIS_NAME,           "NIS-domain-name"      },
230 	{ DH6OPT_NISP_NAME,          "NIS+-domain-name"     },
231 	{ DH6OPT_BCMCS_SERVER_D,     "BCMCS-domain-name"    },
232 	{ DH6OPT_BCMCS_SERVER_A,     "BCMCS-server"         },
233 	{ DH6OPT_GEOCONF_CIVIC,      "Geoconf-Civic"        },
234 	{ DH6OPT_REMOTE_ID,          "Remote-ID"            },
235 	{ DH6OPT_SUBSCRIBER_ID,      "Subscriber-ID"        },
236 	{ DH6OPT_CLIENT_FQDN,        "Client-FQDN"          },
237 	{ DH6OPT_PANA_AGENT,         "PANA-agent"           },
238 	{ DH6OPT_NEW_POSIX_TIMEZONE, "POSIX-timezone"       },
239 	{ DH6OPT_NEW_TZDB_TIMEZONE,  "POSIX-tz-database"    },
240 	{ DH6OPT_ERO,                "Echo-request-option"  },
241 	{ DH6OPT_LQ_QUERY,           "Lease-query"          },
242 	{ DH6OPT_CLIENT_DATA,        "LQ-client-data"       },
243 	{ DH6OPT_CLT_TIME,           "Clt-time"             },
244 	{ DH6OPT_LQ_RELAY_DATA,      "LQ-relay-data"        },
245 	{ DH6OPT_LQ_CLIENT_LINK,     "LQ-client-link"       },
246 	{ DH6OPT_NTP_SERVER,         "NTP-server"           },
247 	{ DH6OPT_AFTR_NAME,          "AFTR-Name"            },
248 	{ DH6OPT_MUDURL,             "MUD-URL"              },
249 	{ 0, NULL }
250 };
251 
252 static const struct tok dh6opt_stcode_str[] = {
253 	{ DH6OPT_STCODE_SUCCESS,          "Success"          }, /* RFC3315 */
254 	{ DH6OPT_STCODE_UNSPECFAIL,       "UnspecFail"       }, /* RFC3315 */
255 	{ DH6OPT_STCODE_NOADDRAVAIL,      "NoAddrsAvail"     }, /* RFC3315 */
256 	{ DH6OPT_STCODE_NOBINDING,        "NoBinding"        }, /* RFC3315 */
257 	{ DH6OPT_STCODE_NOTONLINK,        "NotOnLink"        }, /* RFC3315 */
258 	{ DH6OPT_STCODE_USEMULTICAST,     "UseMulticast"     }, /* RFC3315 */
259 	{ DH6OPT_STCODE_NOPREFIXAVAIL,    "NoPrefixAvail"    }, /* RFC3633 */
260 	{ DH6OPT_STCODE_UNKNOWNQUERYTYPE, "UnknownQueryType" }, /* RFC5007 */
261 	{ DH6OPT_STCODE_MALFORMEDQUERY,   "MalformedQuery"   }, /* RFC5007 */
262 	{ DH6OPT_STCODE_NOTCONFIGURED,    "NotConfigured"    }, /* RFC5007 */
263 	{ DH6OPT_STCODE_NOTALLOWED,       "NotAllowed"       }, /* RFC5007 */
264 	{ 0, NULL }
265 };
266 
267 struct dhcp6opt {
268 	nd_uint16_t dh6opt_type;
269 	nd_uint16_t dh6opt_len;
270 	/* type-dependent data follows */
271 };
272 
273 static const char *
274 dhcp6stcode(const uint16_t code)
275 {
276 	return code > 255 ? "INVALID code" : tok2str(dh6opt_stcode_str, "code%u", code);
277 }
278 
279 static void
280 dhcp6opt_print(netdissect_options *ndo,
281                const u_char *cp, const u_char *ep)
282 {
283 	const struct dhcp6opt *dh6o;
284 	const u_char *tp;
285 	u_int i;
286 	uint16_t opttype;
287 	uint16_t optlen;
288 	uint8_t auth_proto;
289 	uint8_t auth_alg;
290 	uint8_t auth_rdm;
291 	u_int authinfolen, authrealmlen;
292 	u_int remain_len;  /* Length of remaining options */
293 	u_int label_len;   /* Label length */
294 	uint16_t subopt_code;
295 	uint16_t subopt_len;
296 	uint8_t dh6_reconf_type;
297 	uint8_t dh6_lq_query_type;
298 
299 	if (cp == ep)
300 		return;
301 	while (cp < ep) {
302 		if (ep < cp + sizeof(*dh6o))
303 			goto trunc;
304 		dh6o = (const struct dhcp6opt *)cp;
305 		ND_TCHECK_SIZE(dh6o);
306 		optlen = GET_BE_U_2(dh6o->dh6opt_len);
307 		if (ep < cp + sizeof(*dh6o) + optlen)
308 			goto trunc;
309 		opttype = GET_BE_U_2(dh6o->dh6opt_type);
310 		ND_PRINT(" (%s", tok2str(dh6opt_str, "opt_%u", opttype));
311 		ND_TCHECK_LEN(cp + sizeof(*dh6o), optlen);
312 		switch (opttype) {
313 		case DH6OPT_CLIENTID:
314 		case DH6OPT_SERVERID:
315 			if (optlen < 2) {
316 				/*(*/
317 				ND_PRINT(" ?)");
318 				break;
319 			}
320 			tp = (const u_char *)(dh6o + 1);
321 			switch (GET_BE_U_2(tp)) {
322 			case 1:
323 				if (optlen >= 2 + 6) {
324 					ND_PRINT(" hwaddr/time type %u time %u ",
325 					    GET_BE_U_2(tp + 2),
326 					    GET_BE_U_4(tp + 4));
327 					for (i = 8; i < optlen; i++)
328 						ND_PRINT("%02x",
329 							 GET_U_1(tp + i));
330 					/*(*/
331 					ND_PRINT(")");
332 				} else {
333 					/*(*/
334 					ND_PRINT(" ?)");
335 				}
336 				break;
337 			case 2:
338 				if (optlen >= 2 + 8) {
339 					ND_PRINT(" vid ");
340 					for (i = 2; i < 2 + 8; i++)
341 						ND_PRINT("%02x",
342 							 GET_U_1(tp + i));
343 					/*(*/
344 					ND_PRINT(")");
345 				} else {
346 					/*(*/
347 					ND_PRINT(" ?)");
348 				}
349 				break;
350 			case 3:
351 				if (optlen >= 2 + 2) {
352 					ND_PRINT(" hwaddr type %u ",
353 					    GET_BE_U_2(tp + 2));
354 					for (i = 4; i < optlen; i++)
355 						ND_PRINT("%02x",
356 							 GET_U_1(tp + i));
357 					/*(*/
358 					ND_PRINT(")");
359 				} else {
360 					/*(*/
361 					ND_PRINT(" ?)");
362 				}
363 				break;
364 			default:
365 				ND_PRINT(" type %u)", GET_BE_U_2(tp));
366 				break;
367 			}
368 			break;
369 		case DH6OPT_IA_ADDR:
370 			if (optlen < 24) {
371 				/*(*/
372 				ND_PRINT(" ?)");
373 				break;
374 			}
375 			tp = (const u_char *)(dh6o + 1);
376 			ND_PRINT(" %s", GET_IP6ADDR_STRING(tp));
377 			ND_PRINT(" pltime:%u vltime:%u",
378 			    GET_BE_U_4(tp + 16),
379 			    GET_BE_U_4(tp + 20));
380 			if (optlen > 24) {
381 				/* there are sub-options */
382 				dhcp6opt_print(ndo, tp + 24, tp + optlen);
383 			}
384 			ND_PRINT(")");
385 			break;
386 		case DH6OPT_ORO:
387 		case DH6OPT_ERO:
388 			if (optlen % 2) {
389 				ND_PRINT(" ?)");
390 				break;
391 			}
392 			tp = (const u_char *)(dh6o + 1);
393 			for (i = 0; i < optlen; i += 2) {
394 				ND_PRINT(" %s",
395 				    tok2str(dh6opt_str, "opt_%u", GET_BE_U_2(tp + i)));
396 			}
397 			ND_PRINT(")");
398 			break;
399 		case DH6OPT_PREFERENCE:
400 			if (optlen != 1) {
401 				ND_PRINT(" ?)");
402 				break;
403 			}
404 			tp = (const u_char *)(dh6o + 1);
405 			ND_PRINT(" %u)", GET_U_1(tp));
406 			break;
407 		case DH6OPT_ELAPSED_TIME:
408 			if (optlen != 2) {
409 				ND_PRINT(" ?)");
410 				break;
411 			}
412 			tp = (const u_char *)(dh6o + 1);
413 			ND_PRINT(" %u)", GET_BE_U_2(tp));
414 			break;
415 		case DH6OPT_RELAY_MSG:
416 		    {
417 			const u_char *snapend_save;
418 
419 			ND_PRINT(" (");
420 			tp = (const u_char *)(dh6o + 1);
421 			/*
422 			 * Update the snapend to the end of the option before
423 			 * calling recursively dhcp6_print() for the nested
424 			 * packet. Other options may be present after the
425 			 * nested DHCPv6 packet. This prevents that, in
426 			 * dhcp6_print(), for the nested DHCPv6 packet, the
427 			 * remaining length < remaining caplen.
428 			 */
429 			snapend_save = ndo->ndo_snapend;
430 			ndo->ndo_snapend = ND_MIN(tp + optlen, ndo->ndo_snapend);
431 			dhcp6_print(ndo, tp, optlen);
432 			ndo->ndo_snapend = snapend_save;
433 			ND_PRINT(")");
434 			break;
435 		    }
436 		case DH6OPT_AUTH:
437 			if (optlen < 11) {
438 				ND_PRINT(" ?)");
439 				break;
440 			}
441 			tp = (const u_char *)(dh6o + 1);
442 			auth_proto = GET_U_1(tp);
443 			switch (auth_proto) {
444 			case DH6OPT_AUTHPROTO_DELAYED:
445 				ND_PRINT(" proto: delayed");
446 				break;
447 			case DH6OPT_AUTHPROTO_RECONFIG:
448 				ND_PRINT(" proto: reconfigure");
449 				break;
450 			default:
451 				ND_PRINT(" proto: %u", auth_proto);
452 				break;
453 			}
454 			tp++;
455 			auth_alg = GET_U_1(tp);
456 			switch (auth_alg) {
457 			case DH6OPT_AUTHALG_HMACMD5:
458 				/* XXX: may depend on the protocol */
459 				ND_PRINT(", alg: HMAC-MD5");
460 				break;
461 			default:
462 				ND_PRINT(", alg: %u", auth_alg);
463 				break;
464 			}
465 			tp++;
466 			auth_rdm = GET_U_1(tp);
467 			switch (auth_rdm) {
468 			case DH6OPT_AUTHRDM_MONOCOUNTER:
469 				ND_PRINT(", RDM: mono");
470 				break;
471 			default:
472 				ND_PRINT(", RDM: %u", auth_rdm);
473 				break;
474 			}
475 			tp++;
476 			ND_PRINT(", RD:");
477 			for (i = 0; i < 4; i++, tp += 2)
478 				ND_PRINT(" %04x", GET_BE_U_2(tp));
479 
480 			/* protocol dependent part */
481 			authinfolen = optlen - 11;
482 			switch (auth_proto) {
483 			case DH6OPT_AUTHPROTO_DELAYED:
484 				if (authinfolen == 0)
485 					break;
486 				if (authinfolen < 20) {
487 					ND_PRINT(" ??");
488 					break;
489 				}
490 				authrealmlen = authinfolen - 20;
491 				if (authrealmlen > 0) {
492 					ND_PRINT(", realm: ");
493 				}
494 				for (i = 0; i < authrealmlen; i++, tp++)
495 					ND_PRINT("%02x", GET_U_1(tp));
496 				ND_PRINT(", key ID: %08x", GET_BE_U_4(tp));
497 				tp += 4;
498 				ND_PRINT(", HMAC-MD5:");
499 				for (i = 0; i < 4; i++, tp+= 4)
500 					ND_PRINT(" %08x", GET_BE_U_4(tp));
501 				break;
502 			case DH6OPT_AUTHPROTO_RECONFIG:
503 				if (authinfolen != 17) {
504 					ND_PRINT(" ??");
505 					break;
506 				}
507 				switch (GET_U_1(tp)) {
508 				case DH6OPT_AUTHRECONFIG_KEY:
509 					ND_PRINT(" reconfig-key");
510 					break;
511 				case DH6OPT_AUTHRECONFIG_HMACMD5:
512 					ND_PRINT(" type: HMAC-MD5");
513 					break;
514 				default:
515 					ND_PRINT(" type: ??");
516 					break;
517 				}
518 				tp++;
519 				ND_PRINT(" value:");
520 				for (i = 0; i < 4; i++, tp+= 4)
521 					ND_PRINT(" %08x", GET_BE_U_4(tp));
522 				break;
523 			default:
524 				ND_PRINT(" ??");
525 				break;
526 			}
527 
528 			ND_PRINT(")");
529 			break;
530 		case DH6OPT_RAPID_COMMIT: /* nothing todo */
531 			ND_PRINT(")");
532 			break;
533 		case DH6OPT_INTERFACE_ID:
534 		case DH6OPT_SUBSCRIBER_ID:
535 			/*
536 			 * Since we cannot predict the encoding, print hex dump
537 			 * at most 10 characters.
538 			 */
539 			tp = (const u_char *)(dh6o + 1);
540 			ND_PRINT(" ");
541 			for (i = 0; i < optlen && i < 10; i++)
542 				ND_PRINT("%02x", GET_U_1(tp + i));
543 			ND_PRINT("...)");
544 			break;
545 		case DH6OPT_RECONF_MSG:
546 			if (optlen != 1) {
547 				ND_PRINT(" ?)");
548 				break;
549 			}
550 			tp = (const u_char *)(dh6o + 1);
551 			dh6_reconf_type = GET_U_1(tp);
552 			switch (dh6_reconf_type) {
553 			case DH6_RENEW:
554 				ND_PRINT(" for renew)");
555 				break;
556 			case DH6_INFORM_REQ:
557 				ND_PRINT(" for inf-req)");
558 				break;
559 			default:
560 				ND_PRINT(" for ?\?\?(%02x))", dh6_reconf_type);
561 				break;
562 			}
563 			break;
564 		case DH6OPT_RECONF_ACCEPT: /* nothing todo */
565 			ND_PRINT(")");
566 			break;
567 		case DH6OPT_SIP_SERVER_A:
568 		case DH6OPT_DNS_SERVERS:
569 		case DH6OPT_SNTP_SERVERS:
570 		case DH6OPT_NIS_SERVERS:
571 		case DH6OPT_NISP_SERVERS:
572 		case DH6OPT_BCMCS_SERVER_A:
573 		case DH6OPT_PANA_AGENT:
574 		case DH6OPT_LQ_CLIENT_LINK:
575 			if (optlen % 16) {
576 				ND_PRINT(" ?)");
577 				break;
578 			}
579 			tp = (const u_char *)(dh6o + 1);
580 			for (i = 0; i < optlen; i += 16)
581 				ND_PRINT(" %s", GET_IP6ADDR_STRING(tp + i));
582 			ND_PRINT(")");
583 			break;
584 		case DH6OPT_SIP_SERVER_D:
585 		case DH6OPT_DOMAIN_LIST:
586 			tp = (const u_char *)(dh6o + 1);
587 			while (tp < cp + sizeof(*dh6o) + optlen) {
588 				ND_PRINT(" ");
589 				if ((tp = fqdn_print(ndo, tp, cp + sizeof(*dh6o) + optlen)) == NULL)
590 					goto trunc;
591 			}
592 			ND_PRINT(")");
593 			break;
594 		case DH6OPT_STATUS_CODE:
595 			if (optlen < 2) {
596 				ND_PRINT(" ?)");
597 				break;
598 			}
599 			tp = (const u_char *)(dh6o + 1);
600 			ND_PRINT(" %s)", dhcp6stcode(GET_BE_U_2(tp)));
601 			break;
602 		case DH6OPT_IA_NA:
603 		case DH6OPT_IA_PD:
604 			if (optlen < 12) {
605 				ND_PRINT(" ?)");
606 				break;
607 			}
608 			tp = (const u_char *)(dh6o + 1);
609 			ND_PRINT(" IAID:%u T1:%u T2:%u",
610 			    GET_BE_U_4(tp),
611 			    GET_BE_U_4(tp + 4),
612 			    GET_BE_U_4(tp + 8));
613 			if (optlen > 12) {
614 				/* there are sub-options */
615 				dhcp6opt_print(ndo, tp + 12, tp + optlen);
616 			}
617 			ND_PRINT(")");
618 			break;
619 		case DH6OPT_IA_TA:
620 			if (optlen < 4) {
621 				ND_PRINT(" ?)");
622 				break;
623 			}
624 			tp = (const u_char *)(dh6o + 1);
625 			ND_PRINT(" IAID:%u", GET_BE_U_4(tp));
626 			if (optlen > 4) {
627 				/* there are sub-options */
628 				dhcp6opt_print(ndo, tp + 4, tp + optlen);
629 			}
630 			ND_PRINT(")");
631 			break;
632 		case DH6OPT_IA_PD_PREFIX:
633 			if (optlen < 25) {
634 				ND_PRINT(" ?)");
635 				break;
636 			}
637 			tp = (const u_char *)(dh6o + 1);
638 			ND_PRINT(" %s/%u", GET_IP6ADDR_STRING(tp + 9),
639 				 GET_U_1(tp + 8));
640 			ND_PRINT(" pltime:%u vltime:%u",
641 			    GET_BE_U_4(tp),
642 			    GET_BE_U_4(tp + 4));
643 			if (optlen > 25) {
644 				/* there are sub-options */
645 				dhcp6opt_print(ndo, tp + 25, tp + optlen);
646 			}
647 			ND_PRINT(")");
648 			break;
649 		case DH6OPT_LIFETIME:
650 		case DH6OPT_CLT_TIME:
651 			if (optlen != 4) {
652 				ND_PRINT(" ?)");
653 				break;
654 			}
655 			tp = (const u_char *)(dh6o + 1);
656 			ND_PRINT(" %u)", GET_BE_U_4(tp));
657 			break;
658 		case DH6OPT_REMOTE_ID:
659 			if (optlen < 4) {
660 				ND_PRINT(" ?)");
661 				break;
662 			}
663 			tp = (const u_char *)(dh6o + 1);
664 			ND_PRINT(" %u ", GET_BE_U_4(tp));
665 			/*
666 			 * Print hex dump first 10 characters.
667 			 */
668 			for (i = 4; i < optlen && i < 14; i++)
669 				ND_PRINT("%02x", GET_U_1(tp + i));
670 			ND_PRINT("...)");
671 			break;
672 		case DH6OPT_LQ_QUERY:
673 			if (optlen < 17) {
674 				ND_PRINT(" ?)");
675 				break;
676 			}
677 			tp = (const u_char *)(dh6o + 1);
678 			dh6_lq_query_type = GET_U_1(tp);
679 			switch (dh6_lq_query_type) {
680 			case 1:
681 				ND_PRINT(" by-address");
682 				break;
683 			case 2:
684 				ND_PRINT(" by-clientID");
685 				break;
686 			default:
687 				ND_PRINT(" type_%u", dh6_lq_query_type);
688 				break;
689 			}
690 			ND_PRINT(" %s", GET_IP6ADDR_STRING(tp + 1));
691 			if (optlen > 17) {
692 				/* there are query-options */
693 				dhcp6opt_print(ndo, tp + 17, tp + optlen);
694 			}
695 			ND_PRINT(")");
696 			break;
697 		case DH6OPT_CLIENT_DATA:
698 			tp = (const u_char *)(dh6o + 1);
699 			if (optlen > 0) {
700 				/* there are encapsulated options */
701 				dhcp6opt_print(ndo, tp, tp + optlen);
702 			}
703 			ND_PRINT(")");
704 			break;
705 		case DH6OPT_LQ_RELAY_DATA:
706 			if (optlen < 16) {
707 				ND_PRINT(" ?)");
708 				break;
709 			}
710 			tp = (const u_char *)(dh6o + 1);
711 			ND_PRINT(" %s ", GET_IP6ADDR_STRING(tp));
712 			/*
713 			 * Print hex dump first 10 characters.
714 			 */
715 			for (i = 16; i < optlen && i < 26; i++)
716 				ND_PRINT("%02x", GET_U_1(tp + i));
717 			ND_PRINT("...)");
718 			break;
719 		case DH6OPT_NTP_SERVER:
720 			if (optlen < 4) {
721 				ND_PRINT(" ?)");
722 				break;
723 			}
724 			tp = (const u_char *)(dh6o + 1);
725 			while (tp < cp + sizeof(*dh6o) + optlen - 4) {
726 				subopt_code = GET_BE_U_2(tp);
727 				tp += 2;
728 				subopt_len = GET_BE_U_2(tp);
729 				tp += 2;
730 				if (tp + subopt_len > cp + sizeof(*dh6o) + optlen)
731 					goto trunc;
732 				ND_PRINT(" subopt:%u", subopt_code);
733 				switch (subopt_code) {
734 				case DH6OPT_NTP_SUBOPTION_SRV_ADDR:
735 				case DH6OPT_NTP_SUBOPTION_MC_ADDR:
736 					if (subopt_len != 16) {
737 						ND_PRINT(" ?");
738 						break;
739 					}
740 					ND_PRINT(" %s", GET_IP6ADDR_STRING(tp));
741 					break;
742 				case DH6OPT_NTP_SUBOPTION_SRV_FQDN:
743 					ND_PRINT(" ");
744 					if (fqdn_print(ndo, tp, tp + subopt_len) == NULL)
745 						goto trunc;
746 					break;
747 				default:
748 					ND_PRINT(" ?");
749 					break;
750 				}
751 				tp += subopt_len;
752 			}
753 			ND_PRINT(")");
754 			break;
755 		case DH6OPT_AFTR_NAME:
756 			if (optlen < 3) {
757 				ND_PRINT(" ?)");
758 				break;
759 			}
760 			tp = (const u_char *)(dh6o + 1);
761 			remain_len = optlen;
762 			ND_PRINT(" ");
763 			/* Encoding is described in section 3.1 of RFC 1035 */
764 			while (remain_len && GET_U_1(tp)) {
765 				label_len = GET_U_1(tp);
766 				tp++;
767 				if (label_len < remain_len - 1) {
768 					nd_printjnp(ndo, tp, label_len);
769 					tp += label_len;
770 					remain_len -= (label_len + 1);
771 					if(GET_U_1(tp)) ND_PRINT(".");
772 				} else {
773 					ND_PRINT(" ?");
774 					break;
775 				}
776 			}
777 			ND_PRINT(")");
778 			break;
779 		case DH6OPT_NEW_POSIX_TIMEZONE: /* all three of these options */
780 		case DH6OPT_NEW_TZDB_TIMEZONE:	/* are encoded similarly */
781 		case DH6OPT_MUDURL:		/* although GMT might not work */
782 		        if (optlen < 5) {
783 				ND_PRINT(" ?)");
784 				break;
785 			}
786 			tp = (const u_char *)(dh6o + 1);
787 			ND_PRINT(" ");
788 			nd_printjnp(ndo, tp, optlen);
789 			ND_PRINT(")");
790 			break;
791 
792 		default:
793 			ND_PRINT(")");
794 			break;
795 		}
796 
797 		cp += sizeof(*dh6o) + optlen;
798 	}
799 	return;
800 
801 trunc:
802 	nd_print_trunc(ndo);
803 }
804 
805 /*
806  * Print dhcp6 packets
807  */
808 void
809 dhcp6_print(netdissect_options *ndo,
810             const u_char *cp, u_int length)
811 {
812 	const struct dhcp6 *dh6;
813 	const struct dhcp6_relay *dh6relay;
814 	uint8_t msgtype;
815 	const u_char *ep;
816 	const u_char *extp;
817 	const char *name;
818 
819 	ndo->ndo_protocol = "dhcp6";
820 	ND_PRINT("dhcp6");
821 
822 	ep = ndo->ndo_snapend;
823 	if (cp + length < ep)
824 		ep = cp + length;
825 
826 	dh6 = (const struct dhcp6 *)cp;
827 	dh6relay = (const struct dhcp6_relay *)cp;
828 	ND_TCHECK_4(dh6->dh6_msgtypexid.xid);
829 	msgtype = GET_U_1(dh6->dh6_msgtypexid.msgtype);
830 	name = tok2str(dh6_msgtype_str, "msgtype-%u", msgtype);
831 
832 	if (!ndo->ndo_vflag) {
833 		ND_PRINT(" %s", name);
834 		return;
835 	}
836 
837 	/* XXX relay agent messages have to be handled differently */
838 
839 	ND_PRINT(" %s (", name);	/*)*/
840 	if (msgtype != DH6_RELAY_FORW && msgtype != DH6_RELAY_REPLY) {
841 		ND_PRINT("xid=%x",
842 			 GET_BE_U_4(dh6->dh6_msgtypexid.xid) & DH6_XIDMASK);
843 		extp = (const u_char *)(dh6 + 1);
844 		dhcp6opt_print(ndo, extp, ep);
845 	} else {		/* relay messages */
846 		ND_PRINT("linkaddr=%s", GET_IP6ADDR_STRING(dh6relay->dh6relay_linkaddr));
847 
848 		ND_PRINT(" peeraddr=%s", GET_IP6ADDR_STRING(dh6relay->dh6relay_peeraddr));
849 
850 		dhcp6opt_print(ndo, (const u_char *)(dh6relay + 1), ep);
851 	}
852 	/*(*/
853 	ND_PRINT(")");
854 	return;
855 
856 trunc:
857 	nd_print_trunc(ndo);
858 }
859