xref: /netbsd-src/external/bsd/tcpdump/dist/print-dhcp6.c (revision 3117ece4fc4a4ca4489ba793710b60b0d26bab6c)
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 1.10 2024/09/02 16:15:31 christos Exp $");
49 #endif
50 
51 #include <config.h>
52 
53 #include "netdissect-stdinc.h"
54 
55 #include "netdissect.h"
56 #include "addrtoname.h"
57 #include "extract.h"
58 
59 /* lease duration */
60 #define DHCP6_DURATION_INFINITE 0xffffffff
61 
62 /* Error Values */
63 #define DH6ERR_FAILURE		16
64 #define DH6ERR_AUTHFAIL		17
65 #define DH6ERR_POORLYFORMED	18
66 #define DH6ERR_UNAVAIL		19
67 #define DH6ERR_OPTUNAVAIL	20
68 
69 /* Message type */
70 #define DH6_SOLICIT	1
71 #define DH6_ADVERTISE	2
72 #define DH6_REQUEST	3
73 #define DH6_CONFIRM	4
74 #define DH6_RENEW	5
75 #define DH6_REBIND	6
76 #define DH6_REPLY	7
77 #define DH6_RELEASE	8
78 #define DH6_DECLINE	9
79 #define DH6_RECONFIGURE	10
80 #define DH6_INFORM_REQ	11
81 #define DH6_RELAY_FORW	12
82 #define DH6_RELAY_REPLY	13
83 #define DH6_LEASEQUERY	14
84 #define DH6_LQ_REPLY	15
85 
86 static const struct tok dh6_msgtype_str[] = {
87 	{ DH6_SOLICIT,     "solicit"          },
88 	{ DH6_ADVERTISE,   "advertise"        },
89 	{ DH6_REQUEST,     "request"          },
90 	{ DH6_CONFIRM,     "confirm"          },
91 	{ DH6_RENEW,       "renew"            },
92 	{ DH6_REBIND,      "rebind"           },
93 	{ DH6_REPLY,       "reply"            },
94 	{ DH6_RELEASE,     "release"          },
95 	{ DH6_DECLINE,     "decline"          },
96 	{ DH6_RECONFIGURE, "reconfigure"      },
97 	{ DH6_INFORM_REQ,  "inf-req"          },
98 	{ DH6_RELAY_FORW,  "relay-fwd"        },
99 	{ DH6_RELAY_REPLY, "relay-reply"      },
100 	{ DH6_LEASEQUERY,  "leasequery"       },
101 	{ DH6_LQ_REPLY,    "leasequery-reply" },
102 	{ 0, NULL }
103 };
104 
105 /* DHCP6 base packet format */
106 struct dhcp6 {
107 	union {
108 		nd_uint8_t msgtype;
109 		nd_uint32_t xid;
110 	} dh6_msgtypexid;
111 	/* options follow */
112 };
113 #define DH6_XIDMASK	0x00ffffff
114 
115 /* DHCPv6 relay messages */
116 struct dhcp6_relay {
117 	nd_uint8_t dh6relay_msgtype;
118 	nd_uint8_t dh6relay_hcnt;
119 	nd_ipv6    dh6relay_linkaddr;	/* XXX: badly aligned */
120 	nd_ipv6    dh6relay_peeraddr;
121 	/* options follow */
122 };
123 
124 /* options */
125 #define DH6OPT_CLIENTID	1
126 #define DH6OPT_SERVERID	2
127 #  define DUID_LLT  1 /* RFC8415 */
128 #  define DUID_EN   2 /* RFC8415 */
129 #  define DUID_LL   3 /* RFC8415 */
130 #  define DUID_UUID 4 /* RFC6355 */
131 #define DH6OPT_IA_NA 3
132 #define DH6OPT_IA_TA 4
133 #define DH6OPT_IA_ADDR 5
134 #define DH6OPT_ORO 6
135 #define DH6OPT_PREFERENCE 7
136 #  define DH6OPT_PREF_MAX 255
137 #define DH6OPT_ELAPSED_TIME 8
138 #define DH6OPT_RELAY_MSG 9
139 /*#define DH6OPT_SERVER_MSG 10 deprecated */
140 #define DH6OPT_AUTH 11
141 #  define DH6OPT_AUTHPROTO_DELAYED 2
142 #  define DH6OPT_AUTHPROTO_RECONFIG 3
143 #  define DH6OPT_AUTHALG_HMACMD5 1
144 #  define DH6OPT_AUTHRDM_MONOCOUNTER 0
145 #  define DH6OPT_AUTHRECONFIG_KEY 1
146 #  define DH6OPT_AUTHRECONFIG_HMACMD5 2
147 #define DH6OPT_UNICAST 12
148 #define DH6OPT_STATUS_CODE 13
149 #  define DH6OPT_STCODE_SUCCESS 0
150 #  define DH6OPT_STCODE_UNSPECFAIL 1
151 #  define DH6OPT_STCODE_NOADDRAVAIL 2
152 #  define DH6OPT_STCODE_NOBINDING 3
153 #  define DH6OPT_STCODE_NOTONLINK 4
154 #  define DH6OPT_STCODE_USEMULTICAST 5
155 #  define DH6OPT_STCODE_NOPREFIXAVAIL 6
156 #  define DH6OPT_STCODE_UNKNOWNQUERYTYPE 7
157 #  define DH6OPT_STCODE_MALFORMEDQUERY 8
158 #  define DH6OPT_STCODE_NOTCONFIGURED 9
159 #  define DH6OPT_STCODE_NOTALLOWED 10
160 #define DH6OPT_RAPID_COMMIT 14
161 #define DH6OPT_USER_CLASS 15
162 #define DH6OPT_VENDOR_CLASS 16
163 #define DH6OPT_VENDOR_OPTS 17
164 #define DH6OPT_INTERFACE_ID 18
165 #define DH6OPT_RECONF_MSG 19
166 #define DH6OPT_RECONF_ACCEPT 20
167 #define DH6OPT_SIP_SERVER_D 21
168 #define DH6OPT_SIP_SERVER_A 22
169 #define DH6OPT_DNS_SERVERS 23
170 #define DH6OPT_DOMAIN_LIST 24
171 #define DH6OPT_IA_PD 25
172 #define DH6OPT_IA_PD_PREFIX 26
173 #define DH6OPT_NIS_SERVERS 27
174 #define DH6OPT_NISP_SERVERS 28
175 #define DH6OPT_NIS_NAME 29
176 #define DH6OPT_NISP_NAME 30
177 #define DH6OPT_SNTP_SERVERS 31
178 #define DH6OPT_LIFETIME 32
179 #define DH6OPT_BCMCS_SERVER_D 33
180 #define DH6OPT_BCMCS_SERVER_A 34
181 #define DH6OPT_GEOCONF_CIVIC 36
182 #define DH6OPT_REMOTE_ID 37
183 #define DH6OPT_SUBSCRIBER_ID 38
184 #define DH6OPT_CLIENT_FQDN 39
185 #define DH6OPT_PANA_AGENT 40
186 #define DH6OPT_NEW_POSIX_TIMEZONE 41
187 #define DH6OPT_NEW_TZDB_TIMEZONE 42
188 #define DH6OPT_ERO 43
189 #define DH6OPT_LQ_QUERY 44
190 #define DH6OPT_CLIENT_DATA 45
191 #define DH6OPT_CLT_TIME 46
192 #define DH6OPT_LQ_RELAY_DATA 47
193 #define DH6OPT_LQ_CLIENT_LINK 48
194 #define DH6OPT_NTP_SERVER 56
195 #  define DH6OPT_NTP_SUBOPTION_SRV_ADDR 1
196 #  define DH6OPT_NTP_SUBOPTION_MC_ADDR 2
197 #  define DH6OPT_NTP_SUBOPTION_SRV_FQDN 3
198 #define DH6OPT_BOOTFILE_URL 59    /* RFC5970 */
199 #define DH6OPT_AFTR_NAME 64
200 #define DH6OPT_MUDURL 112
201 #define DH6OPT_SZTP_REDIRECT 136  /* RFC8572 */
202 
203 static const struct tok dh6opt_str[] = {
204 	{ DH6OPT_CLIENTID,           "client-ID"            },
205 	{ DH6OPT_SERVERID,           "server-ID"            },
206 	{ DH6OPT_IA_NA,              "IA_NA"                },
207 	{ DH6OPT_IA_TA,              "IA_TA"                },
208 	{ DH6OPT_IA_ADDR,            "IA_ADDR"              },
209 	{ DH6OPT_ORO,                "option-request"       },
210 	{ DH6OPT_PREFERENCE,         "preference"           },
211 	{ DH6OPT_ELAPSED_TIME,       "elapsed-time"         },
212 	{ DH6OPT_RELAY_MSG,          "relay-message"        },
213 	{ DH6OPT_AUTH,               "authentication"       },
214 	{ DH6OPT_UNICAST,            "server-unicast"       },
215 	{ DH6OPT_STATUS_CODE,        "status-code"          },
216 	{ DH6OPT_RAPID_COMMIT,       "rapid-commit"         },
217 	{ DH6OPT_USER_CLASS,         "user-class"           },
218 	{ DH6OPT_VENDOR_CLASS,       "vendor-class"         },
219 	{ DH6OPT_VENDOR_OPTS,        "vendor-specific-info" },
220 	{ DH6OPT_INTERFACE_ID,       "interface-ID"         },
221 	{ DH6OPT_RECONF_MSG,         "reconfigure-message"  },
222 	{ DH6OPT_RECONF_ACCEPT,      "reconfigure-accept"   },
223 	{ DH6OPT_SIP_SERVER_D,       "SIP-servers-domain"   },
224 	{ DH6OPT_SIP_SERVER_A,       "SIP-servers-address"  },
225 	{ DH6OPT_DNS_SERVERS,        "DNS-server"           },
226 	{ DH6OPT_DOMAIN_LIST,        "DNS-search-list"      },
227 	{ DH6OPT_IA_PD,              "IA_PD"                },
228 	{ DH6OPT_IA_PD_PREFIX,       "IA_PD-prefix"         },
229 	{ DH6OPT_SNTP_SERVERS,       "SNTP-servers"         },
230 	{ DH6OPT_LIFETIME,           "lifetime"             },
231 	{ DH6OPT_NIS_SERVERS,        "NIS-server"           },
232 	{ DH6OPT_NISP_SERVERS,       "NIS+-server"          },
233 	{ DH6OPT_NIS_NAME,           "NIS-domain-name"      },
234 	{ DH6OPT_NISP_NAME,          "NIS+-domain-name"     },
235 	{ DH6OPT_BCMCS_SERVER_D,     "BCMCS-domain-name"    },
236 	{ DH6OPT_BCMCS_SERVER_A,     "BCMCS-server"         },
237 	{ DH6OPT_GEOCONF_CIVIC,      "Geoconf-Civic"        },
238 	{ DH6OPT_REMOTE_ID,          "Remote-ID"            },
239 	{ DH6OPT_SUBSCRIBER_ID,      "Subscriber-ID"        },
240 	{ DH6OPT_CLIENT_FQDN,        "Client-FQDN"          },
241 	{ DH6OPT_PANA_AGENT,         "PANA-agent"           },
242 	{ DH6OPT_NEW_POSIX_TIMEZONE, "POSIX-timezone"       },
243 	{ DH6OPT_NEW_TZDB_TIMEZONE,  "POSIX-tz-database"    },
244 	{ DH6OPT_ERO,                "Echo-request-option"  },
245 	{ DH6OPT_LQ_QUERY,           "Lease-query"          },
246 	{ DH6OPT_CLIENT_DATA,        "LQ-client-data"       },
247 	{ DH6OPT_CLT_TIME,           "Clt-time"             },
248 	{ DH6OPT_LQ_RELAY_DATA,      "LQ-relay-data"        },
249 	{ DH6OPT_LQ_CLIENT_LINK,     "LQ-client-link"       },
250 	{ DH6OPT_NTP_SERVER,         "NTP-server"           },
251 	{ DH6OPT_BOOTFILE_URL,       "Bootfile-URL"         },
252 	{ DH6OPT_AFTR_NAME,          "AFTR-Name"            },
253 	{ DH6OPT_MUDURL,             "MUD-URL"              },
254 	{ DH6OPT_SZTP_REDIRECT,      "SZTP-redirect"        },
255 	{ 0, NULL }
256 };
257 
258 static const struct tok dh6opt_stcode_str[] = {
259 	{ DH6OPT_STCODE_SUCCESS,          "Success"          }, /* RFC3315 */
260 	{ DH6OPT_STCODE_UNSPECFAIL,       "UnspecFail"       }, /* RFC3315 */
261 	{ DH6OPT_STCODE_NOADDRAVAIL,      "NoAddrsAvail"     }, /* RFC3315 */
262 	{ DH6OPT_STCODE_NOBINDING,        "NoBinding"        }, /* RFC3315 */
263 	{ DH6OPT_STCODE_NOTONLINK,        "NotOnLink"        }, /* RFC3315 */
264 	{ DH6OPT_STCODE_USEMULTICAST,     "UseMulticast"     }, /* RFC3315 */
265 	{ DH6OPT_STCODE_NOPREFIXAVAIL,    "NoPrefixAvail"    }, /* RFC3633 */
266 	{ DH6OPT_STCODE_UNKNOWNQUERYTYPE, "UnknownQueryType" }, /* RFC5007 */
267 	{ DH6OPT_STCODE_MALFORMEDQUERY,   "MalformedQuery"   }, /* RFC5007 */
268 	{ DH6OPT_STCODE_NOTCONFIGURED,    "NotConfigured"    }, /* RFC5007 */
269 	{ DH6OPT_STCODE_NOTALLOWED,       "NotAllowed"       }, /* RFC5007 */
270 	{ 0, NULL }
271 };
272 
273 struct dhcp6opt {
274 	nd_uint16_t dh6opt_type;
275 	nd_uint16_t dh6opt_len;
276 	/* type-dependent data follows */
277 };
278 
279 static const char *
280 dhcp6stcode(const uint16_t code)
281 {
282 	return code > 255 ? "INVALID code" : tok2str(dh6opt_stcode_str, "code%u", code);
283 }
284 
285 static void
286 dhcp6opt_print(netdissect_options *ndo,
287                const u_char *cp, const u_char *ep)
288 {
289 	const struct dhcp6opt *dh6o;
290 	const u_char *tp;
291 	u_int i;
292 	uint16_t opttype;
293 	uint16_t optlen;
294 	uint8_t auth_proto;
295 	uint8_t auth_alg;
296 	uint8_t auth_rdm;
297 	u_int authinfolen, authrealmlen;
298 	u_int remain_len;  /* Length of remaining options */
299 	u_int label_len;   /* Label length */
300 	uint16_t subopt_code;
301 	uint16_t subopt_len;
302 	uint8_t dh6_reconf_type;
303 	uint8_t dh6_lq_query_type;
304 	u_int first_list_value;
305 	uint16_t remainder_len;
306 
307 	if (cp == ep)
308 		return;
309 	while (cp < ep) {
310 		if (ep < cp + sizeof(*dh6o))
311 			goto trunc;
312 		dh6o = (const struct dhcp6opt *)cp;
313 		ND_TCHECK_SIZE(dh6o);
314 		optlen = GET_BE_U_2(dh6o->dh6opt_len);
315 		if (ep < cp + sizeof(*dh6o) + optlen)
316 			goto trunc;
317 		opttype = GET_BE_U_2(dh6o->dh6opt_type);
318 		ND_PRINT(" (%s", tok2str(dh6opt_str, "opt_%u", opttype));
319 		ND_TCHECK_LEN(cp + sizeof(*dh6o), optlen);
320 		switch (opttype) {
321 		case DH6OPT_CLIENTID:
322 		case DH6OPT_SERVERID:
323 			if (optlen < 2) {
324 				/*(*/
325 				ND_PRINT(" ?)");
326 				break;
327 			}
328 			tp = (const u_char *)(dh6o + 1);
329 			switch (GET_BE_U_2(tp)) {
330 			case DUID_LLT:
331 				if (optlen >= 2 + 6) {
332 					ND_PRINT(" hwaddr/time type %u time %u ",
333 					    GET_BE_U_2(tp + 2),
334 					    GET_BE_U_4(tp + 4));
335 					for (i = 8; i < optlen; 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 DUID_EN:
346 				if (optlen >= 2 + 4) {
347 					ND_PRINT(" enterprise %u ", GET_BE_U_4(tp + 2));
348 					for (i = 2 + 4; i < optlen; i++)
349 						ND_PRINT("%02x",
350 							 GET_U_1(tp + i));
351 					/*(*/
352 					ND_PRINT(")");
353 				} else {
354 					/*(*/
355 					ND_PRINT(" ?)");
356 				}
357 				break;
358 			case DUID_LL:
359 				if (optlen >= 2 + 2) {
360 					ND_PRINT(" hwaddr type %u ",
361 					    GET_BE_U_2(tp + 2));
362 					for (i = 4; i < optlen; i++)
363 						ND_PRINT("%02x",
364 							 GET_U_1(tp + i));
365 					/*(*/
366 					ND_PRINT(")");
367 				} else {
368 					/*(*/
369 					ND_PRINT(" ?)");
370 				}
371 				break;
372 			case DUID_UUID:
373 				ND_PRINT(" uuid ");
374 				if (optlen == 2 + 16) {
375 					for (i = 2; i < optlen; i++)
376 						ND_PRINT("%02x",
377 							 GET_U_1(tp + i));
378 					/*(*/
379 					ND_PRINT(")");
380 				} else {
381 					/*(*/
382 					ND_PRINT(" ?)");
383 				}
384 				break;
385 			default:
386 				ND_PRINT(" type %u)", GET_BE_U_2(tp));
387 				break;
388 			}
389 			break;
390 		case DH6OPT_IA_ADDR:
391 			if (optlen < 24) {
392 				/*(*/
393 				ND_PRINT(" ?)");
394 				break;
395 			}
396 			tp = (const u_char *)(dh6o + 1);
397 			ND_PRINT(" %s", GET_IP6ADDR_STRING(tp));
398 			ND_PRINT(" pltime:%u vltime:%u",
399 			    GET_BE_U_4(tp + 16),
400 			    GET_BE_U_4(tp + 20));
401 			if (optlen > 24) {
402 				/* there are sub-options */
403 				dhcp6opt_print(ndo, tp + 24, tp + optlen);
404 			}
405 			ND_PRINT(")");
406 			break;
407 		case DH6OPT_ORO:
408 		case DH6OPT_ERO:
409 			if (optlen % 2) {
410 				ND_PRINT(" ?)");
411 				break;
412 			}
413 			tp = (const u_char *)(dh6o + 1);
414 			for (i = 0; i < optlen; i += 2) {
415 				ND_PRINT(" %s",
416 				    tok2str(dh6opt_str, "opt_%u", GET_BE_U_2(tp + i)));
417 			}
418 			ND_PRINT(")");
419 			break;
420 		case DH6OPT_PREFERENCE:
421 			if (optlen != 1) {
422 				ND_PRINT(" ?)");
423 				break;
424 			}
425 			tp = (const u_char *)(dh6o + 1);
426 			ND_PRINT(" %u)", GET_U_1(tp));
427 			break;
428 		case DH6OPT_ELAPSED_TIME:
429 			if (optlen != 2) {
430 				ND_PRINT(" ?)");
431 				break;
432 			}
433 			tp = (const u_char *)(dh6o + 1);
434 			ND_PRINT(" %u)", GET_BE_U_2(tp));
435 			break;
436 		case DH6OPT_RELAY_MSG:
437 		    {
438 			const u_char *snapend_save;
439 
440 			ND_PRINT(" (");
441 			tp = (const u_char *)(dh6o + 1);
442 			/*
443 			 * Update the snapend to the end of the option before
444 			 * calling recursively dhcp6_print() for the nested
445 			 * packet. Other options may be present after the
446 			 * nested DHCPv6 packet. This prevents that, in
447 			 * dhcp6_print(), for the nested DHCPv6 packet, the
448 			 * remaining length < remaining caplen.
449 			 */
450 			snapend_save = ndo->ndo_snapend;
451 			ndo->ndo_snapend = ND_MIN(tp + optlen, ndo->ndo_snapend);
452 			dhcp6_print(ndo, tp, optlen);
453 			ndo->ndo_snapend = snapend_save;
454 			ND_PRINT(")");
455 			break;
456 		    }
457 		case DH6OPT_AUTH:
458 			if (optlen < 11) {
459 				ND_PRINT(" ?)");
460 				break;
461 			}
462 			tp = (const u_char *)(dh6o + 1);
463 			auth_proto = GET_U_1(tp);
464 			switch (auth_proto) {
465 			case DH6OPT_AUTHPROTO_DELAYED:
466 				ND_PRINT(" proto: delayed");
467 				break;
468 			case DH6OPT_AUTHPROTO_RECONFIG:
469 				ND_PRINT(" proto: reconfigure");
470 				break;
471 			default:
472 				ND_PRINT(" proto: %u", auth_proto);
473 				break;
474 			}
475 			tp++;
476 			auth_alg = GET_U_1(tp);
477 			switch (auth_alg) {
478 			case DH6OPT_AUTHALG_HMACMD5:
479 				/* XXX: may depend on the protocol */
480 				ND_PRINT(", alg: HMAC-MD5");
481 				break;
482 			default:
483 				ND_PRINT(", alg: %u", auth_alg);
484 				break;
485 			}
486 			tp++;
487 			auth_rdm = GET_U_1(tp);
488 			switch (auth_rdm) {
489 			case DH6OPT_AUTHRDM_MONOCOUNTER:
490 				ND_PRINT(", RDM: mono");
491 				break;
492 			default:
493 				ND_PRINT(", RDM: %u", auth_rdm);
494 				break;
495 			}
496 			tp++;
497 			ND_PRINT(", RD:");
498 			for (i = 0; i < 4; i++, tp += 2)
499 				ND_PRINT(" %04x", GET_BE_U_2(tp));
500 
501 			/* protocol dependent part */
502 			authinfolen = optlen - 11;
503 			switch (auth_proto) {
504 			case DH6OPT_AUTHPROTO_DELAYED:
505 				if (authinfolen == 0)
506 					break;
507 				if (authinfolen < 20) {
508 					ND_PRINT(" ??");
509 					break;
510 				}
511 				authrealmlen = authinfolen - 20;
512 				if (authrealmlen > 0) {
513 					ND_PRINT(", realm: ");
514 				}
515 				for (i = 0; i < authrealmlen; i++, tp++)
516 					ND_PRINT("%02x", GET_U_1(tp));
517 				ND_PRINT(", key ID: %08x", GET_BE_U_4(tp));
518 				tp += 4;
519 				ND_PRINT(", HMAC-MD5:");
520 				for (i = 0; i < 4; i++, tp+= 4)
521 					ND_PRINT(" %08x", GET_BE_U_4(tp));
522 				break;
523 			case DH6OPT_AUTHPROTO_RECONFIG:
524 				if (authinfolen != 17) {
525 					ND_PRINT(" ??");
526 					break;
527 				}
528 				switch (GET_U_1(tp)) {
529 				case DH6OPT_AUTHRECONFIG_KEY:
530 					ND_PRINT(" reconfig-key");
531 					break;
532 				case DH6OPT_AUTHRECONFIG_HMACMD5:
533 					ND_PRINT(" type: HMAC-MD5");
534 					break;
535 				default:
536 					ND_PRINT(" type: ??");
537 					break;
538 				}
539 				tp++;
540 				ND_PRINT(" value:");
541 				for (i = 0; i < 4; i++, tp+= 4)
542 					ND_PRINT(" %08x", GET_BE_U_4(tp));
543 				break;
544 			default:
545 				ND_PRINT(" ??");
546 				break;
547 			}
548 
549 			ND_PRINT(")");
550 			break;
551 		case DH6OPT_RAPID_COMMIT: /* nothing todo */
552 			ND_PRINT(")");
553 			break;
554 		case DH6OPT_INTERFACE_ID:
555 		case DH6OPT_SUBSCRIBER_ID:
556 			/*
557 			 * Since we cannot predict the encoding, print hex dump
558 			 * at most 10 characters.
559 			 */
560 			tp = (const u_char *)(dh6o + 1);
561 			ND_PRINT(" ");
562 			for (i = 0; i < optlen && i < 10; i++)
563 				ND_PRINT("%02x", GET_U_1(tp + i));
564 			ND_PRINT("...)");
565 			break;
566 		case DH6OPT_RECONF_MSG:
567 			if (optlen != 1) {
568 				ND_PRINT(" ?)");
569 				break;
570 			}
571 			tp = (const u_char *)(dh6o + 1);
572 			dh6_reconf_type = GET_U_1(tp);
573 			switch (dh6_reconf_type) {
574 			case DH6_RENEW:
575 				ND_PRINT(" for renew)");
576 				break;
577 			case DH6_INFORM_REQ:
578 				ND_PRINT(" for inf-req)");
579 				break;
580 			default:
581 				ND_PRINT(" for ?\?\?(%02x))", dh6_reconf_type);
582 				break;
583 			}
584 			break;
585 		case DH6OPT_RECONF_ACCEPT: /* nothing todo */
586 			ND_PRINT(")");
587 			break;
588 		case DH6OPT_SIP_SERVER_A:
589 		case DH6OPT_DNS_SERVERS:
590 		case DH6OPT_SNTP_SERVERS:
591 		case DH6OPT_NIS_SERVERS:
592 		case DH6OPT_NISP_SERVERS:
593 		case DH6OPT_BCMCS_SERVER_A:
594 		case DH6OPT_PANA_AGENT:
595 		case DH6OPT_LQ_CLIENT_LINK:
596 			if (optlen % 16) {
597 				ND_PRINT(" ?)");
598 				break;
599 			}
600 			tp = (const u_char *)(dh6o + 1);
601 			for (i = 0; i < optlen; i += 16)
602 				ND_PRINT(" %s", GET_IP6ADDR_STRING(tp + i));
603 			ND_PRINT(")");
604 			break;
605 		case DH6OPT_SIP_SERVER_D:
606 		case DH6OPT_DOMAIN_LIST:
607 			tp = (const u_char *)(dh6o + 1);
608 			while (tp < cp + sizeof(*dh6o) + optlen) {
609 				ND_PRINT(" ");
610 				if ((tp = fqdn_print(ndo, tp, cp + sizeof(*dh6o) + optlen)) == NULL)
611 					goto trunc;
612 			}
613 			ND_PRINT(")");
614 			break;
615 		case DH6OPT_STATUS_CODE:
616 			if (optlen < 2) {
617 				ND_PRINT(" ?)");
618 				break;
619 			}
620 			tp = (const u_char *)(dh6o + 1);
621 			ND_PRINT(" %s)", dhcp6stcode(GET_BE_U_2(tp)));
622 			break;
623 		case DH6OPT_IA_NA:
624 		case DH6OPT_IA_PD:
625 			if (optlen < 12) {
626 				ND_PRINT(" ?)");
627 				break;
628 			}
629 			tp = (const u_char *)(dh6o + 1);
630 			ND_PRINT(" IAID:%u T1:%u T2:%u",
631 			    GET_BE_U_4(tp),
632 			    GET_BE_U_4(tp + 4),
633 			    GET_BE_U_4(tp + 8));
634 			if (optlen > 12) {
635 				/* there are sub-options */
636 				dhcp6opt_print(ndo, tp + 12, tp + optlen);
637 			}
638 			ND_PRINT(")");
639 			break;
640 		case DH6OPT_IA_TA:
641 			if (optlen < 4) {
642 				ND_PRINT(" ?)");
643 				break;
644 			}
645 			tp = (const u_char *)(dh6o + 1);
646 			ND_PRINT(" IAID:%u", GET_BE_U_4(tp));
647 			if (optlen > 4) {
648 				/* there are sub-options */
649 				dhcp6opt_print(ndo, tp + 4, tp + optlen);
650 			}
651 			ND_PRINT(")");
652 			break;
653 		case DH6OPT_IA_PD_PREFIX:
654 			if (optlen < 25) {
655 				ND_PRINT(" ?)");
656 				break;
657 			}
658 			tp = (const u_char *)(dh6o + 1);
659 			ND_PRINT(" %s/%u", GET_IP6ADDR_STRING(tp + 9),
660 				 GET_U_1(tp + 8));
661 			ND_PRINT(" pltime:%u vltime:%u",
662 			    GET_BE_U_4(tp),
663 			    GET_BE_U_4(tp + 4));
664 			if (optlen > 25) {
665 				/* there are sub-options */
666 				dhcp6opt_print(ndo, tp + 25, tp + optlen);
667 			}
668 			ND_PRINT(")");
669 			break;
670 		case DH6OPT_LIFETIME:
671 		case DH6OPT_CLT_TIME:
672 			if (optlen != 4) {
673 				ND_PRINT(" ?)");
674 				break;
675 			}
676 			tp = (const u_char *)(dh6o + 1);
677 			ND_PRINT(" %u)", GET_BE_U_4(tp));
678 			break;
679 		case DH6OPT_REMOTE_ID:
680 			if (optlen < 4) {
681 				ND_PRINT(" ?)");
682 				break;
683 			}
684 			tp = (const u_char *)(dh6o + 1);
685 			ND_PRINT(" %u ", GET_BE_U_4(tp));
686 			/*
687 			 * Print hex dump first 10 characters.
688 			 */
689 			for (i = 4; i < optlen && i < 14; i++)
690 				ND_PRINT("%02x", GET_U_1(tp + i));
691 			ND_PRINT("...)");
692 			break;
693 		case DH6OPT_LQ_QUERY:
694 			if (optlen < 17) {
695 				ND_PRINT(" ?)");
696 				break;
697 			}
698 			tp = (const u_char *)(dh6o + 1);
699 			dh6_lq_query_type = GET_U_1(tp);
700 			switch (dh6_lq_query_type) {
701 			case 1:
702 				ND_PRINT(" by-address");
703 				break;
704 			case 2:
705 				ND_PRINT(" by-clientID");
706 				break;
707 			default:
708 				ND_PRINT(" type_%u", dh6_lq_query_type);
709 				break;
710 			}
711 			ND_PRINT(" %s", GET_IP6ADDR_STRING(tp + 1));
712 			if (optlen > 17) {
713 				/* there are query-options */
714 				dhcp6opt_print(ndo, tp + 17, tp + optlen);
715 			}
716 			ND_PRINT(")");
717 			break;
718 		case DH6OPT_CLIENT_DATA:
719 			tp = (const u_char *)(dh6o + 1);
720 			if (optlen > 0) {
721 				/* there are encapsulated options */
722 				dhcp6opt_print(ndo, tp, tp + optlen);
723 			}
724 			ND_PRINT(")");
725 			break;
726 		case DH6OPT_LQ_RELAY_DATA:
727 			if (optlen < 16) {
728 				ND_PRINT(" ?)");
729 				break;
730 			}
731 			tp = (const u_char *)(dh6o + 1);
732 			ND_PRINT(" %s ", GET_IP6ADDR_STRING(tp));
733 			/*
734 			 * Print hex dump first 10 characters.
735 			 */
736 			for (i = 16; i < optlen && i < 26; i++)
737 				ND_PRINT("%02x", GET_U_1(tp + i));
738 			ND_PRINT("...)");
739 			break;
740 		case DH6OPT_NTP_SERVER:
741 			if (optlen < 4) {
742 				ND_PRINT(" ?)");
743 				break;
744 			}
745 			tp = (const u_char *)(dh6o + 1);
746 			while (tp < cp + sizeof(*dh6o) + optlen - 4) {
747 				subopt_code = GET_BE_U_2(tp);
748 				tp += 2;
749 				subopt_len = GET_BE_U_2(tp);
750 				tp += 2;
751 				if (tp + subopt_len > cp + sizeof(*dh6o) + optlen)
752 					goto trunc;
753 				ND_PRINT(" subopt:%u", subopt_code);
754 				switch (subopt_code) {
755 				case DH6OPT_NTP_SUBOPTION_SRV_ADDR:
756 				case DH6OPT_NTP_SUBOPTION_MC_ADDR:
757 					if (subopt_len != 16) {
758 						ND_PRINT(" ?");
759 						break;
760 					}
761 					ND_PRINT(" %s", GET_IP6ADDR_STRING(tp));
762 					break;
763 				case DH6OPT_NTP_SUBOPTION_SRV_FQDN:
764 					ND_PRINT(" ");
765 					if (fqdn_print(ndo, tp, tp + subopt_len) == NULL)
766 						goto trunc;
767 					break;
768 				default:
769 					ND_PRINT(" ?");
770 					break;
771 				}
772 				tp += subopt_len;
773 			}
774 			ND_PRINT(")");
775 			break;
776 		case DH6OPT_AFTR_NAME:
777 			if (optlen < 3) {
778 				ND_PRINT(" ?)");
779 				break;
780 			}
781 			tp = (const u_char *)(dh6o + 1);
782 			remain_len = optlen;
783 			ND_PRINT(" ");
784 			/* Encoding is described in section 3.1 of RFC 1035 */
785 			while (remain_len && GET_U_1(tp)) {
786 				label_len = GET_U_1(tp);
787 				tp++;
788 				if (label_len < remain_len - 1) {
789 					nd_printjnp(ndo, tp, label_len);
790 					tp += label_len;
791 					remain_len -= (label_len + 1);
792 					if(GET_U_1(tp)) ND_PRINT(".");
793 				} else {
794 					ND_PRINT(" ?");
795 					break;
796 				}
797 			}
798 			ND_PRINT(")");
799 			break;
800 		case DH6OPT_NEW_POSIX_TIMEZONE: /* all three of these options */
801 		case DH6OPT_NEW_TZDB_TIMEZONE:	/* are encoded similarly */
802 		case DH6OPT_MUDURL:		/* although GMT might not work */
803 		        if (optlen < 5) {
804 				ND_PRINT(" ?)");
805 				break;
806 			}
807 			tp = (const u_char *)(dh6o + 1);
808 			ND_PRINT(" ");
809 			nd_printjnp(ndo, tp, optlen);
810 			ND_PRINT(")");
811 			break;
812 
813 		case DH6OPT_BOOTFILE_URL:
814 			tp = (const u_char *)(dh6o + 1);
815 			ND_PRINT(" ");
816 			nd_printjn(ndo, tp, optlen);
817 			ND_PRINT(")");
818 			break;
819 
820 		case DH6OPT_SZTP_REDIRECT:
821 		case DH6OPT_USER_CLASS:
822 			ND_PRINT(" ");
823 			tp = (const u_char *)(dh6o + 1);
824 			first_list_value = TRUE;
825 			remainder_len = optlen;
826 			while (remainder_len >= 2) {
827 				if (first_list_value == FALSE) {
828 					ND_PRINT(",");
829 				}
830 				first_list_value = FALSE;
831 				subopt_len = GET_BE_U_2(tp);
832 				if (subopt_len > remainder_len-2) {
833 					break;
834 				}
835 				tp += 2;
836 				nd_printjn(ndo, tp, subopt_len);
837 				tp += subopt_len;
838 				remainder_len -= (subopt_len+2);
839 			}
840 			if (remainder_len != 0 ) {
841 				ND_PRINT(" ?");
842 			}
843 			ND_PRINT(")");
844 			break;
845 
846 		default:
847 			ND_PRINT(")");
848 			break;
849 		}
850 
851 		cp += sizeof(*dh6o) + optlen;
852 	}
853 	return;
854 
855 trunc:
856 	nd_print_trunc(ndo);
857 }
858 
859 /*
860  * Print dhcp6 packets
861  */
862 void
863 dhcp6_print(netdissect_options *ndo,
864             const u_char *cp, u_int length)
865 {
866 	const struct dhcp6 *dh6;
867 	const struct dhcp6_relay *dh6relay;
868 	uint8_t msgtype;
869 	const u_char *ep;
870 	const u_char *extp;
871 	const char *name;
872 
873 	ndo->ndo_protocol = "dhcp6";
874 	ND_PRINT("dhcp6");
875 
876 	ep = ndo->ndo_snapend;
877 	if (cp + length < ep)
878 		ep = cp + length;
879 
880 	dh6 = (const struct dhcp6 *)cp;
881 	dh6relay = (const struct dhcp6_relay *)cp;
882 	ND_TCHECK_4(dh6->dh6_msgtypexid.xid);
883 	msgtype = GET_U_1(dh6->dh6_msgtypexid.msgtype);
884 	name = tok2str(dh6_msgtype_str, "msgtype-%u", msgtype);
885 
886 	if (!ndo->ndo_vflag) {
887 		ND_PRINT(" %s", name);
888 		return;
889 	}
890 
891 	/* XXX relay agent messages have to be handled differently */
892 
893 	ND_PRINT(" %s (", name);	/*)*/
894 	if (msgtype != DH6_RELAY_FORW && msgtype != DH6_RELAY_REPLY) {
895 		ND_PRINT("xid=%x",
896 			 GET_BE_U_4(dh6->dh6_msgtypexid.xid) & DH6_XIDMASK);
897 		extp = (const u_char *)(dh6 + 1);
898 		dhcp6opt_print(ndo, extp, ep);
899 	} else {		/* relay messages */
900 		ND_PRINT("linkaddr=%s", GET_IP6ADDR_STRING(dh6relay->dh6relay_linkaddr));
901 
902 		ND_PRINT(" peeraddr=%s", GET_IP6ADDR_STRING(dh6relay->dh6relay_peeraddr));
903 
904 		dhcp6opt_print(ndo, (const u_char *)(dh6relay + 1), ep);
905 	}
906 	/*(*/
907 	ND_PRINT(")");
908 	return;
909 
910 trunc:
911 	nd_print_trunc(ndo);
912 }
913