xref: /freebsd/contrib/tcpdump/print-dhcp6.c (revision 9247238cc4b8835892a47701136b0fd073f8d67c)
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 #ifdef HAVE_CONFIG_H
47 #include <config.h>
48 #endif
49 
50 #include "netdissect-stdinc.h"
51 
52 #include "netdissect.h"
53 #include "addrtoname.h"
54 #include "extract.h"
55 
56 /* lease duration */
57 #define DHCP6_DURATION_INFINITE 0xffffffff
58 
59 /* Error Values */
60 #define DH6ERR_FAILURE		16
61 #define DH6ERR_AUTHFAIL		17
62 #define DH6ERR_POORLYFORMED	18
63 #define DH6ERR_UNAVAIL		19
64 #define DH6ERR_OPTUNAVAIL	20
65 
66 /* Message type */
67 #define DH6_SOLICIT	1
68 #define DH6_ADVERTISE	2
69 #define DH6_REQUEST	3
70 #define DH6_CONFIRM	4
71 #define DH6_RENEW	5
72 #define DH6_REBIND	6
73 #define DH6_REPLY	7
74 #define DH6_RELEASE	8
75 #define DH6_DECLINE	9
76 #define DH6_RECONFIGURE	10
77 #define DH6_INFORM_REQ	11
78 #define DH6_RELAY_FORW	12
79 #define DH6_RELAY_REPLY	13
80 #define DH6_LEASEQUERY	14
81 #define DH6_LQ_REPLY	15
82 
83 static const struct tok dh6_msgtype_str[] = {
84 	{ DH6_SOLICIT,     "solicit"          },
85 	{ DH6_ADVERTISE,   "advertise"        },
86 	{ DH6_REQUEST,     "request"          },
87 	{ DH6_CONFIRM,     "confirm"          },
88 	{ DH6_RENEW,       "renew"            },
89 	{ DH6_REBIND,      "rebind"           },
90 	{ DH6_REPLY,       "reply"            },
91 	{ DH6_RELEASE,     "release"          },
92 	{ DH6_DECLINE,     "decline"          },
93 	{ DH6_RECONFIGURE, "reconfigure"      },
94 	{ DH6_INFORM_REQ,  "inf-req"          },
95 	{ DH6_RELAY_FORW,  "relay-fwd"        },
96 	{ DH6_RELAY_REPLY, "relay-reply"      },
97 	{ DH6_LEASEQUERY,  "leasequery"       },
98 	{ DH6_LQ_REPLY,    "leasequery-reply" },
99 	{ 0, NULL }
100 };
101 
102 /* DHCP6 base packet format */
103 struct dhcp6 {
104 	union {
105 		nd_uint8_t msgtype;
106 		nd_uint32_t xid;
107 	} dh6_msgtypexid;
108 	/* options follow */
109 };
110 #define DH6_XIDMASK	0x00ffffff
111 
112 /* DHCPv6 relay messages */
113 struct dhcp6_relay {
114 	nd_uint8_t dh6relay_msgtype;
115 	nd_uint8_t dh6relay_hcnt;
116 	nd_ipv6    dh6relay_linkaddr;	/* XXX: badly aligned */
117 	nd_ipv6    dh6relay_peeraddr;
118 	/* options follow */
119 };
120 
121 /* options */
122 #define DH6OPT_CLIENTID	1
123 #define DH6OPT_SERVERID	2
124 #define DH6OPT_IA_NA 3
125 #define DH6OPT_IA_TA 4
126 #define DH6OPT_IA_ADDR 5
127 #define DH6OPT_ORO 6
128 #define DH6OPT_PREFERENCE 7
129 #  define DH6OPT_PREF_MAX 255
130 #define DH6OPT_ELAPSED_TIME 8
131 #define DH6OPT_RELAY_MSG 9
132 /*#define DH6OPT_SERVER_MSG 10 deprecated */
133 #define DH6OPT_AUTH 11
134 #  define DH6OPT_AUTHPROTO_DELAYED 2
135 #  define DH6OPT_AUTHPROTO_RECONFIG 3
136 #  define DH6OPT_AUTHALG_HMACMD5 1
137 #  define DH6OPT_AUTHRDM_MONOCOUNTER 0
138 #  define DH6OPT_AUTHRECONFIG_KEY 1
139 #  define DH6OPT_AUTHRECONFIG_HMACMD5 2
140 #define DH6OPT_UNICAST 12
141 #define DH6OPT_STATUS_CODE 13
142 #  define DH6OPT_STCODE_SUCCESS 0
143 #  define DH6OPT_STCODE_UNSPECFAIL 1
144 #  define DH6OPT_STCODE_NOADDRAVAIL 2
145 #  define DH6OPT_STCODE_NOBINDING 3
146 #  define DH6OPT_STCODE_NOTONLINK 4
147 #  define DH6OPT_STCODE_USEMULTICAST 5
148 #  define DH6OPT_STCODE_NOPREFIXAVAIL 6
149 #  define DH6OPT_STCODE_UNKNOWNQUERYTYPE 7
150 #  define DH6OPT_STCODE_MALFORMEDQUERY 8
151 #  define DH6OPT_STCODE_NOTCONFIGURED 9
152 #  define DH6OPT_STCODE_NOTALLOWED 10
153 #define DH6OPT_RAPID_COMMIT 14
154 #define DH6OPT_USER_CLASS 15
155 #define DH6OPT_VENDOR_CLASS 16
156 #define DH6OPT_VENDOR_OPTS 17
157 #define DH6OPT_INTERFACE_ID 18
158 #define DH6OPT_RECONF_MSG 19
159 #define DH6OPT_RECONF_ACCEPT 20
160 #define DH6OPT_SIP_SERVER_D 21
161 #define DH6OPT_SIP_SERVER_A 22
162 #define DH6OPT_DNS_SERVERS 23
163 #define DH6OPT_DOMAIN_LIST 24
164 #define DH6OPT_IA_PD 25
165 #define DH6OPT_IA_PD_PREFIX 26
166 #define DH6OPT_NIS_SERVERS 27
167 #define DH6OPT_NISP_SERVERS 28
168 #define DH6OPT_NIS_NAME 29
169 #define DH6OPT_NISP_NAME 30
170 #define DH6OPT_SNTP_SERVERS 31
171 #define DH6OPT_LIFETIME 32
172 #define DH6OPT_BCMCS_SERVER_D 33
173 #define DH6OPT_BCMCS_SERVER_A 34
174 #define DH6OPT_GEOCONF_CIVIC 36
175 #define DH6OPT_REMOTE_ID 37
176 #define DH6OPT_SUBSCRIBER_ID 38
177 #define DH6OPT_CLIENT_FQDN 39
178 #define DH6OPT_PANA_AGENT 40
179 #define DH6OPT_NEW_POSIX_TIMEZONE 41
180 #define DH6OPT_NEW_TZDB_TIMEZONE 42
181 #define DH6OPT_ERO 43
182 #define DH6OPT_LQ_QUERY 44
183 #define DH6OPT_CLIENT_DATA 45
184 #define DH6OPT_CLT_TIME 46
185 #define DH6OPT_LQ_RELAY_DATA 47
186 #define DH6OPT_LQ_CLIENT_LINK 48
187 #define DH6OPT_NTP_SERVER 56
188 #  define DH6OPT_NTP_SUBOPTION_SRV_ADDR 1
189 #  define DH6OPT_NTP_SUBOPTION_MC_ADDR 2
190 #  define DH6OPT_NTP_SUBOPTION_SRV_FQDN 3
191 #define DH6OPT_AFTR_NAME 64
192 #define DH6OPT_MUDURL 112
193 
194 static const struct tok dh6opt_str[] = {
195 	{ DH6OPT_CLIENTID,           "client-ID"            },
196 	{ DH6OPT_SERVERID,           "server-ID"            },
197 	{ DH6OPT_IA_NA,              "IA_NA"                },
198 	{ DH6OPT_IA_TA,              "IA_TA"                },
199 	{ DH6OPT_IA_ADDR,            "IA_ADDR"              },
200 	{ DH6OPT_ORO,                "option-request"       },
201 	{ DH6OPT_PREFERENCE,         "preference"           },
202 	{ DH6OPT_ELAPSED_TIME,       "elapsed-time"         },
203 	{ DH6OPT_RELAY_MSG,          "relay-message"        },
204 	{ DH6OPT_AUTH,               "authentication"       },
205 	{ DH6OPT_UNICAST,            "server-unicast"       },
206 	{ DH6OPT_STATUS_CODE,        "status-code"          },
207 	{ DH6OPT_RAPID_COMMIT,       "rapid-commit"         },
208 	{ DH6OPT_USER_CLASS,         "user-class"           },
209 	{ DH6OPT_VENDOR_CLASS,       "vendor-class"         },
210 	{ DH6OPT_VENDOR_OPTS,        "vendor-specific-info" },
211 	{ DH6OPT_INTERFACE_ID,       "interface-ID"         },
212 	{ DH6OPT_RECONF_MSG,         "reconfigure-message"  },
213 	{ DH6OPT_RECONF_ACCEPT,      "reconfigure-accept"   },
214 	{ DH6OPT_SIP_SERVER_D,       "SIP-servers-domain"   },
215 	{ DH6OPT_SIP_SERVER_A,       "SIP-servers-address"  },
216 	{ DH6OPT_DNS_SERVERS,        "DNS-server"           },
217 	{ DH6OPT_DOMAIN_LIST,        "DNS-search-list"      },
218 	{ DH6OPT_IA_PD,              "IA_PD"                },
219 	{ DH6OPT_IA_PD_PREFIX,       "IA_PD-prefix"         },
220 	{ DH6OPT_SNTP_SERVERS,       "SNTP-servers"         },
221 	{ DH6OPT_LIFETIME,           "lifetime"             },
222 	{ DH6OPT_NIS_SERVERS,        "NIS-server"           },
223 	{ DH6OPT_NISP_SERVERS,       "NIS+-server"          },
224 	{ DH6OPT_NIS_NAME,           "NIS-domain-name"      },
225 	{ DH6OPT_NISP_NAME,          "NIS+-domain-name"     },
226 	{ DH6OPT_BCMCS_SERVER_D,     "BCMCS-domain-name"    },
227 	{ DH6OPT_BCMCS_SERVER_A,     "BCMCS-server"         },
228 	{ DH6OPT_GEOCONF_CIVIC,      "Geoconf-Civic"        },
229 	{ DH6OPT_REMOTE_ID,          "Remote-ID"            },
230 	{ DH6OPT_SUBSCRIBER_ID,      "Subscriber-ID"        },
231 	{ DH6OPT_CLIENT_FQDN,        "Client-FQDN"          },
232 	{ DH6OPT_PANA_AGENT,         "PANA-agent"           },
233 	{ DH6OPT_NEW_POSIX_TIMEZONE, "POSIX-timezone"       },
234 	{ DH6OPT_NEW_TZDB_TIMEZONE,  "POSIX-tz-database"    },
235 	{ DH6OPT_ERO,                "Echo-request-option"  },
236 	{ DH6OPT_LQ_QUERY,           "Lease-query"          },
237 	{ DH6OPT_CLIENT_DATA,        "LQ-client-data"       },
238 	{ DH6OPT_CLT_TIME,           "Clt-time"             },
239 	{ DH6OPT_LQ_RELAY_DATA,      "LQ-relay-data"        },
240 	{ DH6OPT_LQ_CLIENT_LINK,     "LQ-client-link"       },
241 	{ DH6OPT_NTP_SERVER,         "NTP-server"           },
242 	{ DH6OPT_AFTR_NAME,          "AFTR-Name"            },
243 	{ DH6OPT_MUDURL,             "MUD-URL"              },
244 	{ 0, NULL }
245 };
246 
247 static const struct tok dh6opt_stcode_str[] = {
248 	{ DH6OPT_STCODE_SUCCESS,          "Success"          }, /* RFC3315 */
249 	{ DH6OPT_STCODE_UNSPECFAIL,       "UnspecFail"       }, /* RFC3315 */
250 	{ DH6OPT_STCODE_NOADDRAVAIL,      "NoAddrsAvail"     }, /* RFC3315 */
251 	{ DH6OPT_STCODE_NOBINDING,        "NoBinding"        }, /* RFC3315 */
252 	{ DH6OPT_STCODE_NOTONLINK,        "NotOnLink"        }, /* RFC3315 */
253 	{ DH6OPT_STCODE_USEMULTICAST,     "UseMulticast"     }, /* RFC3315 */
254 	{ DH6OPT_STCODE_NOPREFIXAVAIL,    "NoPrefixAvail"    }, /* RFC3633 */
255 	{ DH6OPT_STCODE_UNKNOWNQUERYTYPE, "UnknownQueryType" }, /* RFC5007 */
256 	{ DH6OPT_STCODE_MALFORMEDQUERY,   "MalformedQuery"   }, /* RFC5007 */
257 	{ DH6OPT_STCODE_NOTCONFIGURED,    "NotConfigured"    }, /* RFC5007 */
258 	{ DH6OPT_STCODE_NOTALLOWED,       "NotAllowed"       }, /* RFC5007 */
259 	{ 0, NULL }
260 };
261 
262 struct dhcp6opt {
263 	nd_uint16_t dh6opt_type;
264 	nd_uint16_t dh6opt_len;
265 	/* type-dependent data follows */
266 };
267 
268 static const char *
269 dhcp6stcode(const uint16_t code)
270 {
271 	return code > 255 ? "INVALID code" : tok2str(dh6opt_stcode_str, "code%u", code);
272 }
273 
274 static void
275 dhcp6opt_print(netdissect_options *ndo,
276                const u_char *cp, const u_char *ep)
277 {
278 	const struct dhcp6opt *dh6o;
279 	const u_char *tp;
280 	u_int i;
281 	uint16_t opttype;
282 	uint16_t optlen;
283 	uint8_t auth_proto;
284 	uint8_t auth_alg;
285 	uint8_t auth_rdm;
286 	u_int authinfolen, authrealmlen;
287 	u_int remain_len;  /* Length of remaining options */
288 	u_int label_len;   /* Label length */
289 	uint16_t subopt_code;
290 	uint16_t subopt_len;
291 	uint8_t dh6_reconf_type;
292 	uint8_t dh6_lq_query_type;
293 
294 	if (cp == ep)
295 		return;
296 	while (cp < ep) {
297 		if (ep < cp + sizeof(*dh6o))
298 			goto trunc;
299 		dh6o = (const struct dhcp6opt *)cp;
300 		ND_TCHECK_SIZE(dh6o);
301 		optlen = GET_BE_U_2(dh6o->dh6opt_len);
302 		if (ep < cp + sizeof(*dh6o) + optlen)
303 			goto trunc;
304 		opttype = GET_BE_U_2(dh6o->dh6opt_type);
305 		ND_PRINT(" (%s", tok2str(dh6opt_str, "opt_%u", opttype));
306 		ND_TCHECK_LEN(cp + sizeof(*dh6o), optlen);
307 		switch (opttype) {
308 		case DH6OPT_CLIENTID:
309 		case DH6OPT_SERVERID:
310 			if (optlen < 2) {
311 				/*(*/
312 				ND_PRINT(" ?)");
313 				break;
314 			}
315 			tp = (const u_char *)(dh6o + 1);
316 			switch (GET_BE_U_2(tp)) {
317 			case 1:
318 				if (optlen >= 2 + 6) {
319 					ND_PRINT(" hwaddr/time type %u time %u ",
320 					    GET_BE_U_2(tp + 2),
321 					    GET_BE_U_4(tp + 4));
322 					for (i = 8; i < optlen; i++)
323 						ND_PRINT("%02x",
324 							 GET_U_1(tp + i));
325 					/*(*/
326 					ND_PRINT(")");
327 				} else {
328 					/*(*/
329 					ND_PRINT(" ?)");
330 				}
331 				break;
332 			case 2:
333 				if (optlen >= 2 + 8) {
334 					ND_PRINT(" vid ");
335 					for (i = 2; i < 2 + 8; i++)
336 						ND_PRINT("%02x",
337 							 GET_U_1(tp + i));
338 					/*(*/
339 					ND_PRINT(")");
340 				} else {
341 					/*(*/
342 					ND_PRINT(" ?)");
343 				}
344 				break;
345 			case 3:
346 				if (optlen >= 2 + 2) {
347 					ND_PRINT(" hwaddr type %u ",
348 					    GET_BE_U_2(tp + 2));
349 					for (i = 4; i < optlen; i++)
350 						ND_PRINT("%02x",
351 							 GET_U_1(tp + i));
352 					/*(*/
353 					ND_PRINT(")");
354 				} else {
355 					/*(*/
356 					ND_PRINT(" ?)");
357 				}
358 				break;
359 			default:
360 				ND_PRINT(" type %u)", GET_BE_U_2(tp));
361 				break;
362 			}
363 			break;
364 		case DH6OPT_IA_ADDR:
365 			if (optlen < 24) {
366 				/*(*/
367 				ND_PRINT(" ?)");
368 				break;
369 			}
370 			tp = (const u_char *)(dh6o + 1);
371 			ND_PRINT(" %s", GET_IP6ADDR_STRING(tp));
372 			ND_PRINT(" pltime:%u vltime:%u",
373 			    GET_BE_U_4(tp + 16),
374 			    GET_BE_U_4(tp + 20));
375 			if (optlen > 24) {
376 				/* there are sub-options */
377 				dhcp6opt_print(ndo, tp + 24, tp + optlen);
378 			}
379 			ND_PRINT(")");
380 			break;
381 		case DH6OPT_ORO:
382 		case DH6OPT_ERO:
383 			if (optlen % 2) {
384 				ND_PRINT(" ?)");
385 				break;
386 			}
387 			tp = (const u_char *)(dh6o + 1);
388 			for (i = 0; i < optlen; i += 2) {
389 				ND_PRINT(" %s",
390 				    tok2str(dh6opt_str, "opt_%u", GET_BE_U_2(tp + i)));
391 			}
392 			ND_PRINT(")");
393 			break;
394 		case DH6OPT_PREFERENCE:
395 			if (optlen != 1) {
396 				ND_PRINT(" ?)");
397 				break;
398 			}
399 			tp = (const u_char *)(dh6o + 1);
400 			ND_PRINT(" %u)", GET_U_1(tp));
401 			break;
402 		case DH6OPT_ELAPSED_TIME:
403 			if (optlen != 2) {
404 				ND_PRINT(" ?)");
405 				break;
406 			}
407 			tp = (const u_char *)(dh6o + 1);
408 			ND_PRINT(" %u)", GET_BE_U_2(tp));
409 			break;
410 		case DH6OPT_RELAY_MSG:
411 		    {
412 			const u_char *snapend_save;
413 
414 			ND_PRINT(" (");
415 			tp = (const u_char *)(dh6o + 1);
416 			/*
417 			 * Update the snapend to the end of the option before
418 			 * calling recursively dhcp6_print() for the nested
419 			 * packet. Other options may be present after the
420 			 * nested DHCPv6 packet. This prevents that, in
421 			 * dhcp6_print(), for the nested DHCPv6 packet, the
422 			 * remaining length < remaining caplen.
423 			 */
424 			snapend_save = ndo->ndo_snapend;
425 			ndo->ndo_snapend = ND_MIN(tp + optlen, ndo->ndo_snapend);
426 			dhcp6_print(ndo, tp, optlen);
427 			ndo->ndo_snapend = snapend_save;
428 			ND_PRINT(")");
429 			break;
430 		    }
431 		case DH6OPT_AUTH:
432 			if (optlen < 11) {
433 				ND_PRINT(" ?)");
434 				break;
435 			}
436 			tp = (const u_char *)(dh6o + 1);
437 			auth_proto = GET_U_1(tp);
438 			switch (auth_proto) {
439 			case DH6OPT_AUTHPROTO_DELAYED:
440 				ND_PRINT(" proto: delayed");
441 				break;
442 			case DH6OPT_AUTHPROTO_RECONFIG:
443 				ND_PRINT(" proto: reconfigure");
444 				break;
445 			default:
446 				ND_PRINT(" proto: %u", auth_proto);
447 				break;
448 			}
449 			tp++;
450 			auth_alg = GET_U_1(tp);
451 			switch (auth_alg) {
452 			case DH6OPT_AUTHALG_HMACMD5:
453 				/* XXX: may depend on the protocol */
454 				ND_PRINT(", alg: HMAC-MD5");
455 				break;
456 			default:
457 				ND_PRINT(", alg: %u", auth_alg);
458 				break;
459 			}
460 			tp++;
461 			auth_rdm = GET_U_1(tp);
462 			switch (auth_rdm) {
463 			case DH6OPT_AUTHRDM_MONOCOUNTER:
464 				ND_PRINT(", RDM: mono");
465 				break;
466 			default:
467 				ND_PRINT(", RDM: %u", auth_rdm);
468 				break;
469 			}
470 			tp++;
471 			ND_PRINT(", RD:");
472 			for (i = 0; i < 4; i++, tp += 2)
473 				ND_PRINT(" %04x", GET_BE_U_2(tp));
474 
475 			/* protocol dependent part */
476 			authinfolen = optlen - 11;
477 			switch (auth_proto) {
478 			case DH6OPT_AUTHPROTO_DELAYED:
479 				if (authinfolen == 0)
480 					break;
481 				if (authinfolen < 20) {
482 					ND_PRINT(" ??");
483 					break;
484 				}
485 				authrealmlen = authinfolen - 20;
486 				if (authrealmlen > 0) {
487 					ND_PRINT(", realm: ");
488 				}
489 				for (i = 0; i < authrealmlen; i++, tp++)
490 					ND_PRINT("%02x", GET_U_1(tp));
491 				ND_PRINT(", key ID: %08x", GET_BE_U_4(tp));
492 				tp += 4;
493 				ND_PRINT(", HMAC-MD5:");
494 				for (i = 0; i < 4; i++, tp+= 4)
495 					ND_PRINT(" %08x", GET_BE_U_4(tp));
496 				break;
497 			case DH6OPT_AUTHPROTO_RECONFIG:
498 				if (authinfolen != 17) {
499 					ND_PRINT(" ??");
500 					break;
501 				}
502 				switch (GET_U_1(tp)) {
503 				case DH6OPT_AUTHRECONFIG_KEY:
504 					ND_PRINT(" reconfig-key");
505 					break;
506 				case DH6OPT_AUTHRECONFIG_HMACMD5:
507 					ND_PRINT(" type: HMAC-MD5");
508 					break;
509 				default:
510 					ND_PRINT(" type: ??");
511 					break;
512 				}
513 				tp++;
514 				ND_PRINT(" value:");
515 				for (i = 0; i < 4; i++, tp+= 4)
516 					ND_PRINT(" %08x", GET_BE_U_4(tp));
517 				break;
518 			default:
519 				ND_PRINT(" ??");
520 				break;
521 			}
522 
523 			ND_PRINT(")");
524 			break;
525 		case DH6OPT_RAPID_COMMIT: /* nothing todo */
526 			ND_PRINT(")");
527 			break;
528 		case DH6OPT_INTERFACE_ID:
529 		case DH6OPT_SUBSCRIBER_ID:
530 			/*
531 			 * Since we cannot predict the encoding, print hex dump
532 			 * at most 10 characters.
533 			 */
534 			tp = (const u_char *)(dh6o + 1);
535 			ND_PRINT(" ");
536 			for (i = 0; i < optlen && i < 10; i++)
537 				ND_PRINT("%02x", GET_U_1(tp + i));
538 			ND_PRINT("...)");
539 			break;
540 		case DH6OPT_RECONF_MSG:
541 			if (optlen != 1) {
542 				ND_PRINT(" ?)");
543 				break;
544 			}
545 			tp = (const u_char *)(dh6o + 1);
546 			dh6_reconf_type = GET_U_1(tp);
547 			switch (dh6_reconf_type) {
548 			case DH6_RENEW:
549 				ND_PRINT(" for renew)");
550 				break;
551 			case DH6_INFORM_REQ:
552 				ND_PRINT(" for inf-req)");
553 				break;
554 			default:
555 				ND_PRINT(" for ?\?\?(%02x))", dh6_reconf_type);
556 				break;
557 			}
558 			break;
559 		case DH6OPT_RECONF_ACCEPT: /* nothing todo */
560 			ND_PRINT(")");
561 			break;
562 		case DH6OPT_SIP_SERVER_A:
563 		case DH6OPT_DNS_SERVERS:
564 		case DH6OPT_SNTP_SERVERS:
565 		case DH6OPT_NIS_SERVERS:
566 		case DH6OPT_NISP_SERVERS:
567 		case DH6OPT_BCMCS_SERVER_A:
568 		case DH6OPT_PANA_AGENT:
569 		case DH6OPT_LQ_CLIENT_LINK:
570 			if (optlen % 16) {
571 				ND_PRINT(" ?)");
572 				break;
573 			}
574 			tp = (const u_char *)(dh6o + 1);
575 			for (i = 0; i < optlen; i += 16)
576 				ND_PRINT(" %s", GET_IP6ADDR_STRING(tp + i));
577 			ND_PRINT(")");
578 			break;
579 		case DH6OPT_SIP_SERVER_D:
580 		case DH6OPT_DOMAIN_LIST:
581 			tp = (const u_char *)(dh6o + 1);
582 			while (tp < cp + sizeof(*dh6o) + optlen) {
583 				ND_PRINT(" ");
584 				if ((tp = fqdn_print(ndo, tp, cp + sizeof(*dh6o) + optlen)) == NULL)
585 					goto trunc;
586 			}
587 			ND_PRINT(")");
588 			break;
589 		case DH6OPT_STATUS_CODE:
590 			if (optlen < 2) {
591 				ND_PRINT(" ?)");
592 				break;
593 			}
594 			tp = (const u_char *)(dh6o + 1);
595 			ND_PRINT(" %s)", dhcp6stcode(GET_BE_U_2(tp)));
596 			break;
597 		case DH6OPT_IA_NA:
598 		case DH6OPT_IA_PD:
599 			if (optlen < 12) {
600 				ND_PRINT(" ?)");
601 				break;
602 			}
603 			tp = (const u_char *)(dh6o + 1);
604 			ND_PRINT(" IAID:%u T1:%u T2:%u",
605 			    GET_BE_U_4(tp),
606 			    GET_BE_U_4(tp + 4),
607 			    GET_BE_U_4(tp + 8));
608 			if (optlen > 12) {
609 				/* there are sub-options */
610 				dhcp6opt_print(ndo, tp + 12, tp + optlen);
611 			}
612 			ND_PRINT(")");
613 			break;
614 		case DH6OPT_IA_TA:
615 			if (optlen < 4) {
616 				ND_PRINT(" ?)");
617 				break;
618 			}
619 			tp = (const u_char *)(dh6o + 1);
620 			ND_PRINT(" IAID:%u", GET_BE_U_4(tp));
621 			if (optlen > 4) {
622 				/* there are sub-options */
623 				dhcp6opt_print(ndo, tp + 4, tp + optlen);
624 			}
625 			ND_PRINT(")");
626 			break;
627 		case DH6OPT_IA_PD_PREFIX:
628 			if (optlen < 25) {
629 				ND_PRINT(" ?)");
630 				break;
631 			}
632 			tp = (const u_char *)(dh6o + 1);
633 			ND_PRINT(" %s/%u", GET_IP6ADDR_STRING(tp + 9),
634 				 GET_U_1(tp + 8));
635 			ND_PRINT(" pltime:%u vltime:%u",
636 			    GET_BE_U_4(tp),
637 			    GET_BE_U_4(tp + 4));
638 			if (optlen > 25) {
639 				/* there are sub-options */
640 				dhcp6opt_print(ndo, tp + 25, tp + optlen);
641 			}
642 			ND_PRINT(")");
643 			break;
644 		case DH6OPT_LIFETIME:
645 		case DH6OPT_CLT_TIME:
646 			if (optlen != 4) {
647 				ND_PRINT(" ?)");
648 				break;
649 			}
650 			tp = (const u_char *)(dh6o + 1);
651 			ND_PRINT(" %u)", GET_BE_U_4(tp));
652 			break;
653 		case DH6OPT_REMOTE_ID:
654 			if (optlen < 4) {
655 				ND_PRINT(" ?)");
656 				break;
657 			}
658 			tp = (const u_char *)(dh6o + 1);
659 			ND_PRINT(" %u ", GET_BE_U_4(tp));
660 			/*
661 			 * Print hex dump first 10 characters.
662 			 */
663 			for (i = 4; i < optlen && i < 14; i++)
664 				ND_PRINT("%02x", GET_U_1(tp + i));
665 			ND_PRINT("...)");
666 			break;
667 		case DH6OPT_LQ_QUERY:
668 			if (optlen < 17) {
669 				ND_PRINT(" ?)");
670 				break;
671 			}
672 			tp = (const u_char *)(dh6o + 1);
673 			dh6_lq_query_type = GET_U_1(tp);
674 			switch (dh6_lq_query_type) {
675 			case 1:
676 				ND_PRINT(" by-address");
677 				break;
678 			case 2:
679 				ND_PRINT(" by-clientID");
680 				break;
681 			default:
682 				ND_PRINT(" type_%u", dh6_lq_query_type);
683 				break;
684 			}
685 			ND_PRINT(" %s", GET_IP6ADDR_STRING(tp + 1));
686 			if (optlen > 17) {
687 				/* there are query-options */
688 				dhcp6opt_print(ndo, tp + 17, tp + optlen);
689 			}
690 			ND_PRINT(")");
691 			break;
692 		case DH6OPT_CLIENT_DATA:
693 			tp = (const u_char *)(dh6o + 1);
694 			if (optlen > 0) {
695 				/* there are encapsulated options */
696 				dhcp6opt_print(ndo, tp, tp + optlen);
697 			}
698 			ND_PRINT(")");
699 			break;
700 		case DH6OPT_LQ_RELAY_DATA:
701 			if (optlen < 16) {
702 				ND_PRINT(" ?)");
703 				break;
704 			}
705 			tp = (const u_char *)(dh6o + 1);
706 			ND_PRINT(" %s ", GET_IP6ADDR_STRING(tp));
707 			/*
708 			 * Print hex dump first 10 characters.
709 			 */
710 			for (i = 16; i < optlen && i < 26; i++)
711 				ND_PRINT("%02x", GET_U_1(tp + i));
712 			ND_PRINT("...)");
713 			break;
714 		case DH6OPT_NTP_SERVER:
715 			if (optlen < 4) {
716 				ND_PRINT(" ?)");
717 				break;
718 			}
719 			tp = (const u_char *)(dh6o + 1);
720 			while (tp < cp + sizeof(*dh6o) + optlen - 4) {
721 				subopt_code = GET_BE_U_2(tp);
722 				tp += 2;
723 				subopt_len = GET_BE_U_2(tp);
724 				tp += 2;
725 				if (tp + subopt_len > cp + sizeof(*dh6o) + optlen)
726 					goto trunc;
727 				ND_PRINT(" subopt:%u", subopt_code);
728 				switch (subopt_code) {
729 				case DH6OPT_NTP_SUBOPTION_SRV_ADDR:
730 				case DH6OPT_NTP_SUBOPTION_MC_ADDR:
731 					if (subopt_len != 16) {
732 						ND_PRINT(" ?");
733 						break;
734 					}
735 					ND_PRINT(" %s", GET_IP6ADDR_STRING(tp));
736 					break;
737 				case DH6OPT_NTP_SUBOPTION_SRV_FQDN:
738 					ND_PRINT(" ");
739 					if (fqdn_print(ndo, tp, tp + subopt_len) == NULL)
740 						goto trunc;
741 					break;
742 				default:
743 					ND_PRINT(" ?");
744 					break;
745 				}
746 				tp += subopt_len;
747 			}
748 			ND_PRINT(")");
749 			break;
750 		case DH6OPT_AFTR_NAME:
751 			if (optlen < 3) {
752 				ND_PRINT(" ?)");
753 				break;
754 			}
755 			tp = (const u_char *)(dh6o + 1);
756 			remain_len = optlen;
757 			ND_PRINT(" ");
758 			/* Encoding is described in section 3.1 of RFC 1035 */
759 			while (remain_len && GET_U_1(tp)) {
760 				label_len = GET_U_1(tp);
761 				tp++;
762 				if (label_len < remain_len - 1) {
763 					nd_printjnp(ndo, tp, label_len);
764 					tp += label_len;
765 					remain_len -= (label_len + 1);
766 					if(GET_U_1(tp)) ND_PRINT(".");
767 				} else {
768 					ND_PRINT(" ?");
769 					break;
770 				}
771 			}
772 			ND_PRINT(")");
773 			break;
774 		case DH6OPT_NEW_POSIX_TIMEZONE: /* all three of these options */
775 		case DH6OPT_NEW_TZDB_TIMEZONE:	/* are encoded similarly */
776 		case DH6OPT_MUDURL:		/* although GMT might not work */
777 		        if (optlen < 5) {
778 				ND_PRINT(" ?)");
779 				break;
780 			}
781 			tp = (const u_char *)(dh6o + 1);
782 			ND_PRINT(" ");
783 			nd_printjnp(ndo, tp, optlen);
784 			ND_PRINT(")");
785 			break;
786 
787 		default:
788 			ND_PRINT(")");
789 			break;
790 		}
791 
792 		cp += sizeof(*dh6o) + optlen;
793 	}
794 	return;
795 
796 trunc:
797 	nd_print_trunc(ndo);
798 }
799 
800 /*
801  * Print dhcp6 packets
802  */
803 void
804 dhcp6_print(netdissect_options *ndo,
805             const u_char *cp, u_int length)
806 {
807 	const struct dhcp6 *dh6;
808 	const struct dhcp6_relay *dh6relay;
809 	uint8_t msgtype;
810 	const u_char *ep;
811 	const u_char *extp;
812 	const char *name;
813 
814 	ndo->ndo_protocol = "dhcp6";
815 	ND_PRINT("dhcp6");
816 
817 	ep = ndo->ndo_snapend;
818 	if (cp + length < ep)
819 		ep = cp + length;
820 
821 	dh6 = (const struct dhcp6 *)cp;
822 	dh6relay = (const struct dhcp6_relay *)cp;
823 	ND_TCHECK_4(dh6->dh6_msgtypexid.xid);
824 	msgtype = GET_U_1(dh6->dh6_msgtypexid.msgtype);
825 	name = tok2str(dh6_msgtype_str, "msgtype-%u", msgtype);
826 
827 	if (!ndo->ndo_vflag) {
828 		ND_PRINT(" %s", name);
829 		return;
830 	}
831 
832 	/* XXX relay agent messages have to be handled differently */
833 
834 	ND_PRINT(" %s (", name);	/*)*/
835 	if (msgtype != DH6_RELAY_FORW && msgtype != DH6_RELAY_REPLY) {
836 		ND_PRINT("xid=%x",
837 			 GET_BE_U_4(dh6->dh6_msgtypexid.xid) & DH6_XIDMASK);
838 		extp = (const u_char *)(dh6 + 1);
839 		dhcp6opt_print(ndo, extp, ep);
840 	} else {		/* relay messages */
841 		ND_PRINT("linkaddr=%s", GET_IP6ADDR_STRING(dh6relay->dh6relay_linkaddr));
842 
843 		ND_PRINT(" peeraddr=%s", GET_IP6ADDR_STRING(dh6relay->dh6relay_peeraddr));
844 
845 		dhcp6opt_print(ndo, (const u_char *)(dh6relay + 1), ep);
846 	}
847 	/*(*/
848 	ND_PRINT(")");
849 	return;
850 
851 trunc:
852 	nd_print_trunc(ndo);
853 }
854