xref: /freebsd/contrib/tcpdump/print-dhcp6.c (revision 2e5b60079b7d8c3ca68f1390cd90f305e651f8d3)
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: Session Initiation Protocol (SIP) Servers options,
33  *  RFC3633: IPv6 Prefix options,
34  *  RFC3646: DNS Configuration options,
35  *  RFC3898: Network Information Service (NIS) Configuration options,
36  *  RFC4075: Simple Network Time Protocol (SNTP) Configuration option,
37  *  RFC4242: Information Refresh Time option,
38  *  RFC4280: Broadcast and Multicast Control Servers options,
39  *  RFC5908: Network Time Protocol (NTP) Server Option for DHCPv6
40  *  RFC6334: Dual-Stack Lite option,
41  */
42 
43 #define NETDISSECT_REWORKED
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_DURATION_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 #define DH6_LEASEQUERY	14
82 #define DH6_LQ_REPLY	15
83 
84 static const struct tok dh6_msgtype_str[] = {
85 	{ DH6_SOLICIT,     "solicit"          },
86 	{ DH6_ADVERTISE,   "advertise"        },
87 	{ DH6_REQUEST,     "request"          },
88 	{ DH6_CONFIRM,     "confirm"          },
89 	{ DH6_RENEW,       "renew"            },
90 	{ DH6_REBIND,      "rebind"           },
91 	{ DH6_REPLY,       "reply"            },
92 	{ DH6_RELEASE,     "release"          },
93 	{ DH6_DECLINE,     "decline"          },
94 	{ DH6_RECONFIGURE, "reconfigure"      },
95 	{ DH6_INFORM_REQ,  "inf-req"          },
96 	{ DH6_RELAY_FORW,  "relay-fwd"        },
97 	{ DH6_RELAY_REPLY, "relay-reply"      },
98 	{ DH6_LEASEQUERY,  "leasequery"       },
99 	{ DH6_LQ_REPLY,    "leasequery-reply" },
100 	{ 0, NULL }
101 };
102 
103 /* DHCP6 base packet format */
104 struct dhcp6 {
105 	union {
106 		uint8_t m;
107 		uint32_t x;
108 	} dh6_msgtypexid;
109 	/* options follow */
110 };
111 #define dh6_msgtype	dh6_msgtypexid.m
112 #define dh6_xid		dh6_msgtypexid.x
113 #define DH6_XIDMASK	0x00ffffff
114 
115 /* DHCPv6 relay messages */
116 struct dhcp6_relay {
117 	uint8_t dh6relay_msgtype;
118 	uint8_t dh6relay_hcnt;
119 	uint8_t dh6relay_linkaddr[16];	/* XXX: badly aligned */
120 	uint8_t dh6relay_peeraddr[16];
121 	/* options follow */
122 };
123 
124 /* options */
125 #define DH6OPT_CLIENTID	1
126 #define DH6OPT_SERVERID	2
127 #define DH6OPT_IA_NA 3
128 #define DH6OPT_IA_TA 4
129 #define DH6OPT_IA_ADDR 5
130 #define DH6OPT_ORO 6
131 #define DH6OPT_PREFERENCE 7
132 #  define DH6OPT_PREF_MAX 255
133 #define DH6OPT_ELAPSED_TIME 8
134 #define DH6OPT_RELAY_MSG 9
135 /*#define DH6OPT_SERVER_MSG 10 deprecated */
136 #define DH6OPT_AUTH 11
137 #  define DH6OPT_AUTHPROTO_DELAYED 2
138 #  define DH6OPT_AUTHPROTO_RECONFIG 3
139 #  define DH6OPT_AUTHALG_HMACMD5 1
140 #  define DH6OPT_AUTHRDM_MONOCOUNTER 0
141 #  define DH6OPT_AUTHRECONFIG_KEY 1
142 #  define DH6OPT_AUTHRECONFIG_HMACMD5 2
143 #define DH6OPT_UNICAST 12
144 #define DH6OPT_STATUS_CODE 13
145 #  define DH6OPT_STCODE_SUCCESS 0
146 #  define DH6OPT_STCODE_UNSPECFAIL 1
147 #  define DH6OPT_STCODE_NOADDRAVAIL 2
148 #  define DH6OPT_STCODE_NOBINDING 3
149 #  define DH6OPT_STCODE_NOTONLINK 4
150 #  define DH6OPT_STCODE_USEMULTICAST 5
151 #  define DH6OPT_STCODE_NOPREFIXAVAIL 6
152 #  define DH6OPT_STCODE_UNKNOWNQUERYTYPE 7
153 #  define DH6OPT_STCODE_MALFORMEDQUERY 8
154 #  define DH6OPT_STCODE_NOTCONFIGURED 9
155 #  define DH6OPT_STCODE_NOTALLOWED 10
156 #define DH6OPT_RAPID_COMMIT 14
157 #define DH6OPT_USER_CLASS 15
158 #define DH6OPT_VENDOR_CLASS 16
159 #define DH6OPT_VENDOR_OPTS 17
160 #define DH6OPT_INTERFACE_ID 18
161 #define DH6OPT_RECONF_MSG 19
162 #define DH6OPT_RECONF_ACCEPT 20
163 #define DH6OPT_SIP_SERVER_D 21
164 #define DH6OPT_SIP_SERVER_A 22
165 #define DH6OPT_DNS_SERVERS 23
166 #define DH6OPT_DOMAIN_LIST 24
167 #define DH6OPT_IA_PD 25
168 #define DH6OPT_IA_PD_PREFIX 26
169 #define DH6OPT_NIS_SERVERS 27
170 #define DH6OPT_NISP_SERVERS 28
171 #define DH6OPT_NIS_NAME 29
172 #define DH6OPT_NISP_NAME 30
173 #define DH6OPT_SNTP_SERVERS 31
174 #define DH6OPT_LIFETIME 32
175 #define DH6OPT_BCMCS_SERVER_D 33
176 #define DH6OPT_BCMCS_SERVER_A 34
177 #define DH6OPT_GEOCONF_CIVIC 36
178 #define DH6OPT_REMOTE_ID 37
179 #define DH6OPT_SUBSCRIBER_ID 38
180 #define DH6OPT_CLIENT_FQDN 39
181 #define DH6OPT_PANA_AGENT 40
182 #define DH6OPT_NEW_POSIX_TIMEZONE 41
183 #define DH6OPT_NEW_TZDB_TIMEZONE 42
184 #define DH6OPT_ERO 43
185 #define DH6OPT_LQ_QUERY 44
186 #define DH6OPT_CLIENT_DATA 45
187 #define DH6OPT_CLT_TIME 46
188 #define DH6OPT_LQ_RELAY_DATA 47
189 #define DH6OPT_LQ_CLIENT_LINK 48
190 #define DH6OPT_NTP_SERVER 56
191 #  define DH6OPT_NTP_SUBOPTION_SRV_ADDR 1
192 #  define DH6OPT_NTP_SUBOPTION_MC_ADDR 2
193 #  define DH6OPT_NTP_SUBOPTION_SRV_FQDN 3
194 #define DH6OPT_AFTR_NAME 64
195 
196 static const struct tok dh6opt_str[] = {
197 	{ DH6OPT_CLIENTID,           "client-ID"            },
198 	{ DH6OPT_SERVERID,           "server-ID"            },
199 	{ DH6OPT_IA_NA,              "IA_NA"                },
200 	{ DH6OPT_IA_TA,              "IA_TA"                },
201 	{ DH6OPT_IA_ADDR,            "IA_ADDR"              },
202 	{ DH6OPT_ORO,                "option-request"       },
203 	{ DH6OPT_PREFERENCE,         "preference"           },
204 	{ DH6OPT_ELAPSED_TIME,       "elapsed-time"         },
205 	{ DH6OPT_RELAY_MSG,          "relay-message"        },
206 	{ DH6OPT_AUTH,               "authentication"       },
207 	{ DH6OPT_UNICAST,            "server-unicast"       },
208 	{ DH6OPT_STATUS_CODE,        "status-code"          },
209 	{ DH6OPT_RAPID_COMMIT,       "rapid-commit"         },
210 	{ DH6OPT_USER_CLASS,         "user-class"           },
211 	{ DH6OPT_VENDOR_CLASS,       "vendor-class"         },
212 	{ DH6OPT_VENDOR_OPTS,        "vendor-specific-info" },
213 	{ DH6OPT_INTERFACE_ID,       "interface-ID"         },
214 	{ DH6OPT_RECONF_MSG,         "reconfigure-message"  },
215 	{ DH6OPT_RECONF_ACCEPT,      "reconfigure-accept"   },
216 	{ DH6OPT_SIP_SERVER_D,       "SIP-servers-domain"   },
217 	{ DH6OPT_SIP_SERVER_A,       "SIP-servers-address"  },
218 	{ DH6OPT_DNS_SERVERS,        "DNS-server"           },
219 	{ DH6OPT_DOMAIN_LIST,        "DNS-search-list"      },
220 	{ DH6OPT_IA_PD,              "IA_PD"                },
221 	{ DH6OPT_IA_PD_PREFIX,       "IA_PD-prefix"         },
222 	{ DH6OPT_SNTP_SERVERS,       "SNTP-servers"         },
223 	{ DH6OPT_LIFETIME,           "lifetime"             },
224 	{ DH6OPT_NIS_SERVERS,        "NIS-server"           },
225 	{ DH6OPT_NISP_SERVERS,       "NIS+-server"          },
226 	{ DH6OPT_NIS_NAME,           "NIS-domain-name"      },
227 	{ DH6OPT_NISP_NAME,          "NIS+-domain-name"     },
228 	{ DH6OPT_BCMCS_SERVER_D,     "BCMCS-domain-name"    },
229 	{ DH6OPT_BCMCS_SERVER_A,     "BCMCS-server"         },
230 	{ DH6OPT_GEOCONF_CIVIC,      "Geoconf-Civic"        },
231 	{ DH6OPT_REMOTE_ID,          "Remote-ID"            },
232 	{ DH6OPT_SUBSCRIBER_ID,      "Subscriber-ID"        },
233 	{ DH6OPT_CLIENT_FQDN,        "Client-FQDN"          },
234 	{ DH6OPT_PANA_AGENT,         "PANA-agent"           },
235 	{ DH6OPT_NEW_POSIX_TIMEZONE, "POSIX-timezone"       },
236 	{ DH6OPT_NEW_TZDB_TIMEZONE,  "POSIX-tz-database"    },
237 	{ DH6OPT_ERO,                "Echo-request-option"  },
238 	{ DH6OPT_LQ_QUERY,           "Lease-query"          },
239 	{ DH6OPT_CLIENT_DATA,        "LQ-client-data"       },
240 	{ DH6OPT_CLT_TIME,           "Clt-time"             },
241 	{ DH6OPT_LQ_RELAY_DATA,      "LQ-relay-data"        },
242 	{ DH6OPT_LQ_CLIENT_LINK,     "LQ-client-link"       },
243 	{ DH6OPT_NTP_SERVER,         "NTP-server"           },
244 	{ DH6OPT_AFTR_NAME,          "AFTR-Name"            },
245 	{ 0, NULL }
246 };
247 
248 static const struct tok dh6opt_stcode_str[] = {
249 	{ DH6OPT_STCODE_SUCCESS,          "success"            },
250 	{ DH6OPT_STCODE_UNSPECFAIL,       "unspec failure"     },
251 	{ DH6OPT_STCODE_NOADDRAVAIL,      "no addresses"       },
252 	{ DH6OPT_STCODE_NOBINDING,        "no binding"         },
253 	{ DH6OPT_STCODE_NOTONLINK,        "not on-link"        },
254 	{ DH6OPT_STCODE_USEMULTICAST,     "use multicast"      },
255 	{ DH6OPT_STCODE_NOPREFIXAVAIL,    "no prefixes"        },
256 	{ DH6OPT_STCODE_UNKNOWNQUERYTYPE, "unknown query type" },
257 	{ DH6OPT_STCODE_MALFORMEDQUERY,   "malformed query"    },
258 	{ DH6OPT_STCODE_NOTCONFIGURED,    "not configured"     },
259 	{ DH6OPT_STCODE_NOTALLOWED,       "not allowed"        },
260 	{ 0, NULL }
261 };
262 
263 struct dhcp6opt {
264 	uint16_t dh6opt_type;
265 	uint16_t dh6opt_len;
266 	/* type-dependent data follows */
267 };
268 
269 static const char *
270 dhcp6stcode(const uint16_t code)
271 {
272 	return code > 255 ? "INVALID code" : tok2str(dh6opt_stcode_str, "code%u", code);
273 }
274 
275 static void
276 dhcp6opt_print(netdissect_options *ndo,
277                const u_char *cp, const u_char *ep)
278 {
279 	const struct dhcp6opt *dh6o;
280 	const u_char *tp;
281 	size_t i;
282 	uint16_t opttype;
283 	size_t optlen;
284 	uint8_t auth_proto;
285 	u_int authinfolen, authrealmlen;
286 	int remain_len;  /* Length of remaining options */
287 	int label_len;   /* Label length */
288 	uint16_t subopt_code;
289 	uint16_t subopt_len;
290 
291 	if (cp == ep)
292 		return;
293 	while (cp < ep) {
294 		if (ep < cp + sizeof(*dh6o))
295 			goto trunc;
296 		dh6o = (struct dhcp6opt *)cp;
297 		ND_TCHECK(*dh6o);
298 		optlen = EXTRACT_16BITS(&dh6o->dh6opt_len);
299 		if (ep < cp + sizeof(*dh6o) + optlen)
300 			goto trunc;
301 		opttype = EXTRACT_16BITS(&dh6o->dh6opt_type);
302 		ND_PRINT((ndo, " (%s", tok2str(dh6opt_str, "opt_%u", opttype)));
303 		switch (opttype) {
304 		case DH6OPT_CLIENTID:
305 		case DH6OPT_SERVERID:
306 			if (optlen < 2) {
307 				/*(*/
308 				ND_PRINT((ndo, " ?)"));
309 				break;
310 			}
311 			tp = (u_char *)(dh6o + 1);
312 			switch (EXTRACT_16BITS(tp)) {
313 			case 1:
314 				if (optlen >= 2 + 6) {
315 					ND_PRINT((ndo, " hwaddr/time type %u time %u ",
316 					    EXTRACT_16BITS(&tp[2]),
317 					    EXTRACT_32BITS(&tp[4])));
318 					for (i = 8; i < optlen; i++)
319 						ND_PRINT((ndo, "%02x", tp[i]));
320 					/*(*/
321 					ND_PRINT((ndo, ")"));
322 				} else {
323 					/*(*/
324 					ND_PRINT((ndo, " ?)"));
325 				}
326 				break;
327 			case 2:
328 				if (optlen >= 2 + 8) {
329 					ND_PRINT((ndo, " vid "));
330 					for (i = 2; i < 2 + 8; i++)
331 						ND_PRINT((ndo, "%02x", tp[i]));
332 					/*(*/
333 					ND_PRINT((ndo, ")"));
334 				} else {
335 					/*(*/
336 					ND_PRINT((ndo, " ?)"));
337 				}
338 				break;
339 			case 3:
340 				if (optlen >= 2 + 2) {
341 					ND_PRINT((ndo, " hwaddr type %u ",
342 					    EXTRACT_16BITS(&tp[2])));
343 					for (i = 4; i < optlen; i++)
344 						ND_PRINT((ndo, "%02x", tp[i]));
345 					/*(*/
346 					ND_PRINT((ndo, ")"));
347 				} else {
348 					/*(*/
349 					ND_PRINT((ndo, " ?)"));
350 				}
351 				break;
352 			default:
353 				ND_PRINT((ndo, " type %d)", EXTRACT_16BITS(tp)));
354 				break;
355 			}
356 			break;
357 		case DH6OPT_IA_ADDR:
358 			if (optlen < 24) {
359 				/*(*/
360 				ND_PRINT((ndo, " ?)"));
361 				break;
362 			}
363 			tp = (u_char *)(dh6o + 1);
364 			ND_PRINT((ndo, " %s", ip6addr_string(ndo, &tp[0])));
365 			ND_PRINT((ndo, " pltime:%u vltime:%u",
366 			    EXTRACT_32BITS(&tp[16]),
367 			    EXTRACT_32BITS(&tp[20])));
368 			if (optlen > 24) {
369 				/* there are sub-options */
370 				dhcp6opt_print(ndo, tp + 24, tp + optlen);
371 			}
372 			ND_PRINT((ndo, ")"));
373 			break;
374 		case DH6OPT_ORO:
375 		case DH6OPT_ERO:
376 			if (optlen % 2) {
377 				ND_PRINT((ndo, " ?)"));
378 				break;
379 			}
380 			tp = (u_char *)(dh6o + 1);
381 			for (i = 0; i < optlen; i += 2) {
382 				ND_PRINT((ndo, " %s",
383 				    tok2str(dh6opt_str, "opt_%u", EXTRACT_16BITS(&tp[i]))));
384 			}
385 			ND_PRINT((ndo, ")"));
386 			break;
387 		case DH6OPT_PREFERENCE:
388 			if (optlen != 1) {
389 				ND_PRINT((ndo, " ?)"));
390 				break;
391 			}
392 			tp = (u_char *)(dh6o + 1);
393 			ND_PRINT((ndo, " %d)", *tp));
394 			break;
395 		case DH6OPT_ELAPSED_TIME:
396 			if (optlen != 2) {
397 				ND_PRINT((ndo, " ?)"));
398 				break;
399 			}
400 			tp = (u_char *)(dh6o + 1);
401 			ND_PRINT((ndo, " %d)", EXTRACT_16BITS(tp)));
402 			break;
403 		case DH6OPT_RELAY_MSG:
404 			ND_PRINT((ndo, " ("));
405 			tp = (u_char *)(dh6o + 1);
406 			dhcp6_print(ndo, tp, optlen);
407 			ND_PRINT((ndo, ")"));
408 			break;
409 		case DH6OPT_AUTH:
410 			if (optlen < 11) {
411 				ND_PRINT((ndo, " ?)"));
412 				break;
413 			}
414 			tp = (u_char *)(dh6o + 1);
415 			auth_proto = *tp;
416 			switch (auth_proto) {
417 			case DH6OPT_AUTHPROTO_DELAYED:
418 				ND_PRINT((ndo, " proto: delayed"));
419 				break;
420 			case DH6OPT_AUTHPROTO_RECONFIG:
421 				ND_PRINT((ndo, " proto: reconfigure"));
422 				break;
423 			default:
424 				ND_PRINT((ndo, " proto: %d", auth_proto));
425 				break;
426 			}
427 			tp++;
428 			switch (*tp) {
429 			case DH6OPT_AUTHALG_HMACMD5:
430 				/* XXX: may depend on the protocol */
431 				ND_PRINT((ndo, ", alg: HMAC-MD5"));
432 				break;
433 			default:
434 				ND_PRINT((ndo, ", alg: %d", *tp));
435 				break;
436 			}
437 			tp++;
438 			switch (*tp) {
439 			case DH6OPT_AUTHRDM_MONOCOUNTER:
440 				ND_PRINT((ndo, ", RDM: mono"));
441 				break;
442 			default:
443 				ND_PRINT((ndo, ", RDM: %d", *tp));
444 				break;
445 			}
446 			tp++;
447 			ND_PRINT((ndo, ", RD:"));
448 			for (i = 0; i < 4; i++, tp += 2)
449 				ND_PRINT((ndo, " %04x", EXTRACT_16BITS(tp)));
450 
451 			/* protocol dependent part */
452 			authinfolen = optlen - 11;
453 			switch (auth_proto) {
454 			case DH6OPT_AUTHPROTO_DELAYED:
455 				if (authinfolen == 0)
456 					break;
457 				if (authinfolen < 20) {
458 					ND_PRINT((ndo, " ??"));
459 					break;
460 				}
461 				authrealmlen = authinfolen - 20;
462 				if (authrealmlen > 0) {
463 					ND_PRINT((ndo, ", realm: "));
464 				}
465 				for (i = 0; i < authrealmlen; i++, tp++)
466 					ND_PRINT((ndo, "%02x", *tp));
467 				ND_PRINT((ndo, ", key ID: %08x", EXTRACT_32BITS(tp)));
468 				tp += 4;
469 				ND_PRINT((ndo, ", HMAC-MD5:"));
470 				for (i = 0; i < 4; i++, tp+= 4)
471 					ND_PRINT((ndo, " %08x", EXTRACT_32BITS(tp)));
472 				break;
473 			case DH6OPT_AUTHPROTO_RECONFIG:
474 				if (authinfolen != 17) {
475 					ND_PRINT((ndo, " ??"));
476 					break;
477 				}
478 				switch (*tp++) {
479 				case DH6OPT_AUTHRECONFIG_KEY:
480 					ND_PRINT((ndo, " reconfig-key"));
481 					break;
482 				case DH6OPT_AUTHRECONFIG_HMACMD5:
483 					ND_PRINT((ndo, " type: HMAC-MD5"));
484 					break;
485 				default:
486 					ND_PRINT((ndo, " type: ??"));
487 					break;
488 				}
489 				ND_PRINT((ndo, " value:"));
490 				for (i = 0; i < 4; i++, tp+= 4)
491 					ND_PRINT((ndo, " %08x", EXTRACT_32BITS(tp)));
492 				break;
493 			default:
494 				ND_PRINT((ndo, " ??"));
495 				break;
496 			}
497 
498 			ND_PRINT((ndo, ")"));
499 			break;
500 		case DH6OPT_RAPID_COMMIT: /* nothing todo */
501 			ND_PRINT((ndo, ")"));
502 			break;
503 		case DH6OPT_INTERFACE_ID:
504 		case DH6OPT_SUBSCRIBER_ID:
505 			/*
506 			 * Since we cannot predict the encoding, print hex dump
507 			 * at most 10 characters.
508 			 */
509 			tp = (u_char *)(dh6o + 1);
510 			ND_PRINT((ndo, " "));
511 			for (i = 0; i < optlen && i < 10; i++)
512 				ND_PRINT((ndo, "%02x", tp[i]));
513 			ND_PRINT((ndo, "...)"));
514 			break;
515 		case DH6OPT_RECONF_MSG:
516 			tp = (u_char *)(dh6o + 1);
517 			switch (*tp) {
518 			case DH6_RENEW:
519 				ND_PRINT((ndo, " for renew)"));
520 				break;
521 			case DH6_INFORM_REQ:
522 				ND_PRINT((ndo, " for inf-req)"));
523 				break;
524 			default:
525 				ND_PRINT((ndo, " for ?\?\?(%02x))", *tp));
526 				break;
527 			}
528 			break;
529 		case DH6OPT_RECONF_ACCEPT: /* nothing todo */
530 			ND_PRINT((ndo, ")"));
531 			break;
532 		case DH6OPT_SIP_SERVER_A:
533 		case DH6OPT_DNS_SERVERS:
534 		case DH6OPT_SNTP_SERVERS:
535 		case DH6OPT_NIS_SERVERS:
536 		case DH6OPT_NISP_SERVERS:
537 		case DH6OPT_BCMCS_SERVER_A:
538 		case DH6OPT_PANA_AGENT:
539 		case DH6OPT_LQ_CLIENT_LINK:
540 			if (optlen % 16) {
541 				ND_PRINT((ndo, " ?)"));
542 				break;
543 			}
544 			tp = (u_char *)(dh6o + 1);
545 			for (i = 0; i < optlen; i += 16)
546 				ND_PRINT((ndo, " %s", ip6addr_string(ndo, &tp[i])));
547 			ND_PRINT((ndo, ")"));
548 			break;
549 		case DH6OPT_SIP_SERVER_D:
550 		case DH6OPT_DOMAIN_LIST:
551 			tp = (u_char *)(dh6o + 1);
552 			while (tp < cp + sizeof(*dh6o) + optlen) {
553 				ND_PRINT((ndo, " "));
554 				if ((tp = ns_nprint(ndo, tp, cp + sizeof(*dh6o) + optlen)) == NULL)
555 					goto trunc;
556 			}
557 			ND_PRINT((ndo, ")"));
558 			break;
559 		case DH6OPT_STATUS_CODE:
560 			if (optlen < 2) {
561 				ND_PRINT((ndo, " ?)"));
562 				break;
563 			}
564 			tp = (u_char *)(dh6o + 1);
565 			ND_PRINT((ndo, " %s)", dhcp6stcode(EXTRACT_16BITS(&tp[0]))));
566 			break;
567 		case DH6OPT_IA_NA:
568 		case DH6OPT_IA_PD:
569 			if (optlen < 12) {
570 				ND_PRINT((ndo, " ?)"));
571 				break;
572 			}
573 			tp = (u_char *)(dh6o + 1);
574 			ND_PRINT((ndo, " IAID:%u T1:%u T2:%u",
575 			    EXTRACT_32BITS(&tp[0]),
576 			    EXTRACT_32BITS(&tp[4]),
577 			    EXTRACT_32BITS(&tp[8])));
578 			if (optlen > 12) {
579 				/* there are sub-options */
580 				dhcp6opt_print(ndo, tp + 12, tp + optlen);
581 			}
582 			ND_PRINT((ndo, ")"));
583 			break;
584 		case DH6OPT_IA_TA:
585 			if (optlen < 4) {
586 				ND_PRINT((ndo, " ?)"));
587 				break;
588 			}
589 			tp = (u_char *)(dh6o + 1);
590 			ND_PRINT((ndo, " IAID:%u", EXTRACT_32BITS(tp)));
591 			if (optlen > 4) {
592 				/* there are sub-options */
593 				dhcp6opt_print(ndo, tp + 4, tp + optlen);
594 			}
595 			ND_PRINT((ndo, ")"));
596 			break;
597 		case DH6OPT_IA_PD_PREFIX:
598 			if (optlen < 25) {
599 				ND_PRINT((ndo, " ?)"));
600 				break;
601 			}
602 			tp = (u_char *)(dh6o + 1);
603 			ND_PRINT((ndo, " %s/%d", ip6addr_string(ndo, &tp[9]), tp[8]));
604 			ND_PRINT((ndo, " pltime:%u vltime:%u",
605 			    EXTRACT_32BITS(&tp[0]),
606 			    EXTRACT_32BITS(&tp[4])));
607 			if (optlen > 25) {
608 				/* there are sub-options */
609 				dhcp6opt_print(ndo, tp + 25, tp + optlen);
610 			}
611 			ND_PRINT((ndo, ")"));
612 			break;
613 		case DH6OPT_LIFETIME:
614 		case DH6OPT_CLT_TIME:
615 			if (optlen != 4) {
616 				ND_PRINT((ndo, " ?)"));
617 				break;
618 			}
619 			tp = (u_char *)(dh6o + 1);
620 			ND_PRINT((ndo, " %d)", EXTRACT_32BITS(tp)));
621 			break;
622 		case DH6OPT_REMOTE_ID:
623 			if (optlen < 4) {
624 				ND_PRINT((ndo, " ?)"));
625 				break;
626 			}
627 			tp = (u_char *)(dh6o + 1);
628 			ND_PRINT((ndo, " %d ", EXTRACT_32BITS(tp)));
629 			/*
630 			 * Print hex dump first 10 characters.
631 			 */
632 			for (i = 4; i < optlen && i < 14; i++)
633 				ND_PRINT((ndo, "%02x", tp[i]));
634 			ND_PRINT((ndo, "...)"));
635 			break;
636 		case DH6OPT_LQ_QUERY:
637 			if (optlen < 17) {
638 				ND_PRINT((ndo, " ?)"));
639 				break;
640 			}
641 			tp = (u_char *)(dh6o + 1);
642 			switch (*tp) {
643 			case 1:
644 				ND_PRINT((ndo, " by-address"));
645 				break;
646 			case 2:
647 				ND_PRINT((ndo, " by-clientID"));
648 				break;
649 			default:
650 				ND_PRINT((ndo, " type_%d", (int)*tp));
651 				break;
652 			}
653 			ND_PRINT((ndo, " %s", ip6addr_string(ndo, &tp[1])));
654 			if (optlen > 17) {
655 				/* there are query-options */
656 				dhcp6opt_print(ndo, tp + 17, tp + optlen);
657 			}
658 			ND_PRINT((ndo, ")"));
659 			break;
660 		case DH6OPT_CLIENT_DATA:
661 			tp = (u_char *)(dh6o + 1);
662 			if (optlen > 0) {
663 				/* there are encapsulated options */
664 				dhcp6opt_print(ndo, tp, tp + optlen);
665 			}
666 			ND_PRINT((ndo, ")"));
667 			break;
668 		case DH6OPT_LQ_RELAY_DATA:
669 			if (optlen < 16) {
670 				ND_PRINT((ndo, " ?)"));
671 				break;
672 			}
673 			tp = (u_char *)(dh6o + 1);
674 			ND_PRINT((ndo, " %s ", ip6addr_string(ndo, &tp[0])));
675 			/*
676 			 * Print hex dump first 10 characters.
677 			 */
678 			for (i = 16; i < optlen && i < 26; i++)
679 				ND_PRINT((ndo, "%02x", tp[i]));
680 			ND_PRINT((ndo, "...)"));
681 			break;
682 		case DH6OPT_NTP_SERVER:
683 			if (optlen < 4) {
684 				ND_PRINT((ndo, " ?)"));
685 				break;
686 			}
687 			tp = (u_char *)(dh6o + 1);
688 			while (tp < cp + sizeof(*dh6o) + optlen - 4) {
689 				subopt_code = EXTRACT_16BITS(tp);
690 				tp += 2;
691 				subopt_len = EXTRACT_16BITS(tp);
692 				tp += 2;
693 				if (tp + subopt_len > cp + sizeof(*dh6o) + optlen)
694 					goto trunc;
695 				ND_PRINT((ndo, " subopt:%d", subopt_code));
696 				switch (subopt_code) {
697 				case DH6OPT_NTP_SUBOPTION_SRV_ADDR:
698 				case DH6OPT_NTP_SUBOPTION_MC_ADDR:
699 					if (subopt_len != 16) {
700 						ND_PRINT((ndo, " ?"));
701 						break;
702 					}
703 					ND_PRINT((ndo, " %s", ip6addr_string(ndo, &tp[0])));
704 					break;
705 				case DH6OPT_NTP_SUBOPTION_SRV_FQDN:
706 					ND_PRINT((ndo, " "));
707 					if (ns_nprint(ndo, tp, tp + subopt_len) == NULL)
708 						goto trunc;
709 					break;
710 				default:
711 					ND_PRINT((ndo, " ?"));
712 					break;
713 				}
714 				tp += subopt_len;
715 			}
716 			ND_PRINT((ndo, ")"));
717 			break;
718 		case DH6OPT_AFTR_NAME:
719 			if (optlen < 3) {
720 				ND_PRINT((ndo, " ?)"));
721 				break;
722 			}
723 			tp = (u_char *)(dh6o + 1);
724 			remain_len = optlen;
725 			ND_PRINT((ndo, " "));
726 			/* Encoding is described in section 3.1 of RFC 1035 */
727 			while (remain_len && *tp) {
728 				label_len =  *tp++;
729 				if (label_len < remain_len - 1) {
730 					ND_PRINT((ndo, "%.*s", label_len, tp));
731 					tp += label_len;
732 					remain_len -= (label_len + 1);
733 					if(*tp) ND_PRINT((ndo, "."));
734 				} else {
735 					ND_PRINT((ndo, " ?"));
736 					break;
737 				}
738 			}
739 			ND_PRINT((ndo, ")"));
740 			break;
741 		default:
742 			ND_PRINT((ndo, ")"));
743 			break;
744 		}
745 
746 		cp += sizeof(*dh6o) + optlen;
747 	}
748 	return;
749 
750 trunc:
751 	ND_PRINT((ndo, "[|dhcp6ext]"));
752 }
753 
754 /*
755  * Print dhcp6 packets
756  */
757 void
758 dhcp6_print(netdissect_options *ndo,
759             const u_char *cp, u_int length)
760 {
761 	struct dhcp6 *dh6;
762 	struct dhcp6_relay *dh6relay;
763 	const u_char *ep;
764 	u_char *extp;
765 	const char *name;
766 
767 	ND_PRINT((ndo, "dhcp6"));
768 
769 	ep = (u_char *)ndo->ndo_snapend;
770 	if (cp + length < ep)
771 		ep = cp + length;
772 
773 	dh6 = (struct dhcp6 *)cp;
774 	dh6relay = (struct dhcp6_relay *)cp;
775 	ND_TCHECK(dh6->dh6_xid);
776 	name = tok2str(dh6_msgtype_str, "msgtype-%u", dh6->dh6_msgtype);
777 
778 	if (!ndo->ndo_vflag) {
779 		ND_PRINT((ndo, " %s", name));
780 		return;
781 	}
782 
783 	/* XXX relay agent messages have to be handled differently */
784 
785 	ND_PRINT((ndo, " %s (", name));	/*)*/
786 	if (dh6->dh6_msgtype != DH6_RELAY_FORW &&
787 	    dh6->dh6_msgtype != DH6_RELAY_REPLY) {
788 		ND_PRINT((ndo, "xid=%x", EXTRACT_32BITS(&dh6->dh6_xid) & DH6_XIDMASK));
789 		extp = (u_char *)(dh6 + 1);
790 		dhcp6opt_print(ndo, extp, ep);
791 	} else {		/* relay messages */
792 		struct in6_addr addr6;
793 
794 		ND_TCHECK(dh6relay->dh6relay_peeraddr);
795 
796 		memcpy(&addr6, dh6relay->dh6relay_linkaddr, sizeof (addr6));
797 		ND_PRINT((ndo, "linkaddr=%s", ip6addr_string(ndo, &addr6)));
798 
799 		memcpy(&addr6, dh6relay->dh6relay_peeraddr, sizeof (addr6));
800 		ND_PRINT((ndo, " peeraddr=%s", ip6addr_string(ndo, &addr6)));
801 
802 		dhcp6opt_print(ndo, (u_char *)(dh6relay + 1), ep);
803 	}
804 	/*(*/
805 	ND_PRINT((ndo, ")"));
806 	return;
807 
808 trunc:
809 	ND_PRINT((ndo, "[|dhcp6]"));
810 }
811