1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #define NETDISSECT_REWORKED
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26 
27 #include <tcpdump-stdinc.h>
28 
29 #include "nameser.h"
30 
31 #include <string.h>
32 
33 #include "interface.h"
34 #include "addrtoname.h"
35 #include "extract.h"                    /* must come after interface.h */
36 
37 static const char *ns_ops[] = {
38 	"", " inv_q", " stat", " op3", " notify", " update", " op6", " op7",
39 	" op8", " updateA", " updateD", " updateDA",
40 	" updateM", " updateMA", " zoneInit", " zoneRef",
41 };
42 
43 static const char *ns_resp[] = {
44 	"", " FormErr", " ServFail", " NXDomain",
45 	" NotImp", " Refused", " YXDomain", " YXRRSet",
46 	" NXRRSet", " NotAuth", " NotZone", " Resp11",
47 	" Resp12", " Resp13", " Resp14", " NoChange",
48 };
49 
50 /* skip over a domain name */
51 static const u_char *
ns_nskip(netdissect_options * ndo,register const u_char * cp)52 ns_nskip(netdissect_options *ndo,
53          register const u_char *cp)
54 {
55 	register u_char i;
56 
57 	if (!ND_TTEST2(*cp, 1))
58 		return (NULL);
59 	i = *cp++;
60 	while (i) {
61 		if ((i & INDIR_MASK) == INDIR_MASK)
62 			return (cp + 1);
63 		if ((i & INDIR_MASK) == EDNS0_MASK) {
64 			int bitlen, bytelen;
65 
66 			if ((i & ~INDIR_MASK) != EDNS0_ELT_BITLABEL)
67 				return(NULL); /* unknown ELT */
68 			if (!ND_TTEST2(*cp, 1))
69 				return (NULL);
70 			if ((bitlen = *cp++) == 0)
71 				bitlen = 256;
72 			bytelen = (bitlen + 7) / 8;
73 			cp += bytelen;
74 		} else
75 			cp += i;
76 		if (!ND_TTEST2(*cp, 1))
77 			return (NULL);
78 		i = *cp++;
79 	}
80 	return (cp);
81 }
82 
83 /* print a <domain-name> */
84 static const u_char *
blabel_print(netdissect_options * ndo,const u_char * cp)85 blabel_print(netdissect_options *ndo,
86              const u_char *cp)
87 {
88 	int bitlen, slen, b;
89 	const u_char *bitp, *lim;
90 	char tc;
91 
92 	if (!ND_TTEST2(*cp, 1))
93 		return(NULL);
94 	if ((bitlen = *cp) == 0)
95 		bitlen = 256;
96 	slen = (bitlen + 3) / 4;
97 	lim = cp + 1 + slen;
98 
99 	/* print the bit string as a hex string */
100 	ND_PRINT((ndo, "\\[x"));
101 	for (bitp = cp + 1, b = bitlen; bitp < lim && b > 7; b -= 8, bitp++) {
102 		ND_TCHECK(*bitp);
103 		ND_PRINT((ndo, "%02x", *bitp));
104 	}
105 	if (b > 4) {
106 		ND_TCHECK(*bitp);
107 		tc = *bitp++;
108 		ND_PRINT((ndo, "%02x", tc & (0xff << (8 - b))));
109 	} else if (b > 0) {
110 		ND_TCHECK(*bitp);
111 		tc = *bitp++;
112 		ND_PRINT((ndo, "%1x", ((tc >> 4) & 0x0f) & (0x0f << (4 - b))));
113 	}
114 	ND_PRINT((ndo, "/%d]", bitlen));
115 	return lim;
116 trunc:
117 	ND_PRINT((ndo, ".../%d]", bitlen));
118 	return NULL;
119 }
120 
121 static int
labellen(netdissect_options * ndo,const u_char * cp)122 labellen(netdissect_options *ndo,
123          const u_char *cp)
124 {
125 	register u_int i;
126 
127 	if (!ND_TTEST2(*cp, 1))
128 		return(-1);
129 	i = *cp;
130 	if ((i & INDIR_MASK) == EDNS0_MASK) {
131 		int bitlen, elt;
132 		if ((elt = (i & ~INDIR_MASK)) != EDNS0_ELT_BITLABEL) {
133 			ND_PRINT((ndo, "<ELT %d>", elt));
134 			return(-1);
135 		}
136 		if (!ND_TTEST2(*(cp + 1), 1))
137 			return(-1);
138 		if ((bitlen = *(cp + 1)) == 0)
139 			bitlen = 256;
140 		return(((bitlen + 7) / 8) + 1);
141 	} else
142 		return(i);
143 }
144 
145 const u_char *
ns_nprint(netdissect_options * ndo,register const u_char * cp,register const u_char * bp)146 ns_nprint(netdissect_options *ndo,
147           register const u_char *cp, register const u_char *bp)
148 {
149 	register u_int i, l;
150 	register const u_char *rp = NULL;
151 	register int compress = 0;
152 	int chars_processed;
153 	int elt;
154 	int data_size = ndo->ndo_snapend - bp;
155 
156 	if ((l = labellen(ndo, cp)) == (u_int)-1)
157 		return(NULL);
158 	if (!ND_TTEST2(*cp, 1))
159 		return(NULL);
160 	chars_processed = 1;
161 	if (((i = *cp++) & INDIR_MASK) != INDIR_MASK) {
162 		compress = 0;
163 		rp = cp + l;
164 	}
165 
166 	if (i != 0)
167 		while (i && cp < ndo->ndo_snapend) {
168 			if ((i & INDIR_MASK) == INDIR_MASK) {
169 				if (!compress) {
170 					rp = cp + 1;
171 					compress = 1;
172 				}
173 				if (!ND_TTEST2(*cp, 1))
174 					return(NULL);
175 				cp = bp + (((i << 8) | *cp) & 0x3fff);
176 				if ((l = labellen(ndo, cp)) == (u_int)-1)
177 					return(NULL);
178 				if (!ND_TTEST2(*cp, 1))
179 					return(NULL);
180 				i = *cp++;
181 				chars_processed++;
182 
183 				/*
184 				 * If we've looked at every character in
185 				 * the message, this pointer will make
186 				 * us look at some character again,
187 				 * which means we're looping.
188 				 */
189 				if (chars_processed >= data_size) {
190 					ND_PRINT((ndo, "<LOOP>"));
191 					return (NULL);
192 				}
193 				continue;
194 			}
195 			if ((i & INDIR_MASK) == EDNS0_MASK) {
196 				elt = (i & ~INDIR_MASK);
197 				switch(elt) {
198 				case EDNS0_ELT_BITLABEL:
199 					if (blabel_print(ndo, cp) == NULL)
200 						return (NULL);
201 					break;
202 				default:
203 					/* unknown ELT */
204 					ND_PRINT((ndo, "<ELT %d>", elt));
205 					return(NULL);
206 				}
207 			} else {
208 				if (fn_printn(ndo, cp, l, ndo->ndo_snapend))
209 					return(NULL);
210 			}
211 
212 			cp += l;
213 			chars_processed += l;
214 			ND_PRINT((ndo, "."));
215 			if ((l = labellen(ndo, cp)) == (u_int)-1)
216 				return(NULL);
217 			if (!ND_TTEST2(*cp, 1))
218 				return(NULL);
219 			i = *cp++;
220 			chars_processed++;
221 			if (!compress)
222 				rp += l + 1;
223 		}
224 	else
225 		ND_PRINT((ndo, "."));
226 	return (rp);
227 }
228 
229 /* print a <character-string> */
230 static const u_char *
ns_cprint(netdissect_options * ndo,register const u_char * cp)231 ns_cprint(netdissect_options *ndo,
232           register const u_char *cp)
233 {
234 	register u_int i;
235 
236 	if (!ND_TTEST2(*cp, 1))
237 		return (NULL);
238 	i = *cp++;
239 	if (fn_printn(ndo, cp, i, ndo->ndo_snapend))
240 		return (NULL);
241 	return (cp + i);
242 }
243 
244 /* http://www.iana.org/assignments/dns-parameters */
245 const struct tok ns_type2str[] = {
246 	{ T_A,		"A" },			/* RFC 1035 */
247 	{ T_NS,		"NS" },			/* RFC 1035 */
248 	{ T_MD,		"MD" },			/* RFC 1035 */
249 	{ T_MF,		"MF" },			/* RFC 1035 */
250 	{ T_CNAME,	"CNAME" },		/* RFC 1035 */
251 	{ T_SOA,	"SOA" },		/* RFC 1035 */
252 	{ T_MB,		"MB" },			/* RFC 1035 */
253 	{ T_MG,		"MG" },			/* RFC 1035 */
254 	{ T_MR,		"MR" },			/* RFC 1035 */
255 	{ T_NULL,	"NULL" },		/* RFC 1035 */
256 	{ T_WKS,	"WKS" },		/* RFC 1035 */
257 	{ T_PTR,	"PTR" },		/* RFC 1035 */
258 	{ T_HINFO,	"HINFO" },		/* RFC 1035 */
259 	{ T_MINFO,	"MINFO" },		/* RFC 1035 */
260 	{ T_MX,		"MX" },			/* RFC 1035 */
261 	{ T_TXT,	"TXT" },		/* RFC 1035 */
262 	{ T_RP,		"RP" },			/* RFC 1183 */
263 	{ T_AFSDB,	"AFSDB" },		/* RFC 1183 */
264 	{ T_X25,	"X25" },		/* RFC 1183 */
265 	{ T_ISDN,	"ISDN" },		/* RFC 1183 */
266 	{ T_RT,		"RT" },			/* RFC 1183 */
267 	{ T_NSAP,	"NSAP" },		/* RFC 1706 */
268 	{ T_NSAP_PTR,	"NSAP_PTR" },
269 	{ T_SIG,	"SIG" },		/* RFC 2535 */
270 	{ T_KEY,	"KEY" },		/* RFC 2535 */
271 	{ T_PX,		"PX" },			/* RFC 2163 */
272 	{ T_GPOS,	"GPOS" },		/* RFC 1712 */
273 	{ T_AAAA,	"AAAA" },		/* RFC 1886 */
274 	{ T_LOC,	"LOC" },		/* RFC 1876 */
275 	{ T_NXT,	"NXT" },		/* RFC 2535 */
276 	{ T_EID,	"EID" },		/* Nimrod */
277 	{ T_NIMLOC,	"NIMLOC" },		/* Nimrod */
278 	{ T_SRV,	"SRV" },		/* RFC 2782 */
279 	{ T_ATMA,	"ATMA" },		/* ATM Forum */
280 	{ T_NAPTR,	"NAPTR" },		/* RFC 2168, RFC 2915 */
281 	{ T_KX,		"KX" },			/* RFC 2230 */
282 	{ T_CERT,	"CERT" },		/* RFC 2538 */
283 	{ T_A6,		"A6" },			/* RFC 2874 */
284 	{ T_DNAME,	"DNAME" },		/* RFC 2672 */
285 	{ T_SINK, 	"SINK" },
286 	{ T_OPT,	"OPT" },		/* RFC 2671 */
287 	{ T_APL, 	"APL" },		/* RFC 3123 */
288 	{ T_DS,		"DS" },			/* RFC 4034 */
289 	{ T_SSHFP,	"SSHFP" },		/* RFC 4255 */
290 	{ T_IPSECKEY,	"IPSECKEY" },		/* RFC 4025 */
291 	{ T_RRSIG, 	"RRSIG" },		/* RFC 4034 */
292 	{ T_NSEC,	"NSEC" },		/* RFC 4034 */
293 	{ T_DNSKEY,	"DNSKEY" },		/* RFC 4034 */
294 	{ T_SPF,	"SPF" },		/* RFC-schlitt-spf-classic-02.txt */
295 	{ T_UINFO,	"UINFO" },
296 	{ T_UID,	"UID" },
297 	{ T_GID,	"GID" },
298 	{ T_UNSPEC,	"UNSPEC" },
299 	{ T_UNSPECA,	"UNSPECA" },
300 	{ T_TKEY,	"TKEY" },		/* RFC 2930 */
301 	{ T_TSIG,	"TSIG" },		/* RFC 2845 */
302 	{ T_IXFR,	"IXFR" },		/* RFC 1995 */
303 	{ T_AXFR,	"AXFR" },		/* RFC 1035 */
304 	{ T_MAILB,	"MAILB" },		/* RFC 1035 */
305 	{ T_MAILA,	"MAILA" },		/* RFC 1035 */
306 	{ T_ANY,	"ANY" },
307 	{ 0,		NULL }
308 };
309 
310 const struct tok ns_class2str[] = {
311 	{ C_IN,		"IN" },		/* Not used */
312 	{ C_CHAOS,	"CHAOS" },
313 	{ C_HS,		"HS" },
314 	{ C_ANY,	"ANY" },
315 	{ 0,		NULL }
316 };
317 
318 /* print a query */
319 static const u_char *
ns_qprint(netdissect_options * ndo,register const u_char * cp,register const u_char * bp,int is_mdns)320 ns_qprint(netdissect_options *ndo,
321           register const u_char *cp, register const u_char *bp, int is_mdns)
322 {
323 	register const u_char *np = cp;
324 	register u_int i, class;
325 
326 	cp = ns_nskip(ndo, cp);
327 
328 	if (cp == NULL || !ND_TTEST2(*cp, 4))
329 		return(NULL);
330 
331 	/* print the qtype */
332 	i = EXTRACT_16BITS(cp);
333 	cp += 2;
334 	ND_PRINT((ndo, " %s", tok2str(ns_type2str, "Type%d", i)));
335 	/* print the qclass (if it's not IN) */
336 	i = EXTRACT_16BITS(cp);
337 	cp += 2;
338 	if (is_mdns)
339 		class = (i & ~C_QU);
340 	else
341 		class = i;
342 	if (class != C_IN)
343 		ND_PRINT((ndo, " %s", tok2str(ns_class2str, "(Class %d)", class)));
344 	if (is_mdns) {
345 		ND_PRINT((ndo, i & C_QU ? " (QU)" : " (QM)"));
346 	}
347 
348 	ND_PRINT((ndo, "? "));
349 	cp = ns_nprint(ndo, np, bp);
350 	return(cp ? cp + 4 : NULL);
351 }
352 
353 /* print a reply */
354 static const u_char *
ns_rprint(netdissect_options * ndo,register const u_char * cp,register const u_char * bp,int is_mdns)355 ns_rprint(netdissect_options *ndo,
356           register const u_char *cp, register const u_char *bp, int is_mdns)
357 {
358 	register u_int i, class, opt_flags = 0;
359 	register u_short typ, len;
360 	register const u_char *rp;
361 
362 	if (ndo->ndo_vflag) {
363 		ND_PRINT((ndo, " "));
364 		if ((cp = ns_nprint(ndo, cp, bp)) == NULL)
365 			return NULL;
366 	} else
367 		cp = ns_nskip(ndo, cp);
368 
369 	if (cp == NULL || !ND_TTEST2(*cp, 10))
370 		return (ndo->ndo_snapend);
371 
372 	/* print the type/qtype */
373 	typ = EXTRACT_16BITS(cp);
374 	cp += 2;
375 	/* print the class (if it's not IN and the type isn't OPT) */
376 	i = EXTRACT_16BITS(cp);
377 	cp += 2;
378 	if (is_mdns)
379 		class = (i & ~C_CACHE_FLUSH);
380 	else
381 		class = i;
382 	if (class != C_IN && typ != T_OPT)
383 		ND_PRINT((ndo, " %s", tok2str(ns_class2str, "(Class %d)", class)));
384 	if (is_mdns) {
385 		if (i & C_CACHE_FLUSH)
386 			ND_PRINT((ndo, " (Cache flush)"));
387 	}
388 
389 	if (typ == T_OPT) {
390 		/* get opt flags */
391 		cp += 2;
392 		opt_flags = EXTRACT_16BITS(cp);
393 		/* ignore rest of ttl field */
394 		cp += 2;
395 	} else if (ndo->ndo_vflag > 2) {
396 		/* print ttl */
397 		ND_PRINT((ndo, " ["));
398 		relts_print(ndo, EXTRACT_32BITS(cp));
399 		ND_PRINT((ndo, "]"));
400 		cp += 4;
401 	} else {
402 		/* ignore ttl */
403 		cp += 4;
404 	}
405 
406 	len = EXTRACT_16BITS(cp);
407 	cp += 2;
408 
409 	rp = cp + len;
410 
411 	ND_PRINT((ndo, " %s", tok2str(ns_type2str, "Type%d", typ)));
412 	if (rp > ndo->ndo_snapend)
413 		return(NULL);
414 
415 	switch (typ) {
416 	case T_A:
417 		if (!ND_TTEST2(*cp, sizeof(struct in_addr)))
418 			return(NULL);
419 		ND_PRINT((ndo, " %s", intoa(htonl(EXTRACT_32BITS(cp)))));
420 		break;
421 
422 	case T_NS:
423 	case T_CNAME:
424 	case T_PTR:
425 #ifdef T_DNAME
426 	case T_DNAME:
427 #endif
428 		ND_PRINT((ndo, " "));
429 		if (ns_nprint(ndo, cp, bp) == NULL)
430 			return(NULL);
431 		break;
432 
433 	case T_SOA:
434 		if (!ndo->ndo_vflag)
435 			break;
436 		ND_PRINT((ndo, " "));
437 		if ((cp = ns_nprint(ndo, cp, bp)) == NULL)
438 			return(NULL);
439 		ND_PRINT((ndo, " "));
440 		if ((cp = ns_nprint(ndo, cp, bp)) == NULL)
441 			return(NULL);
442 		if (!ND_TTEST2(*cp, 5 * 4))
443 			return(NULL);
444 		ND_PRINT((ndo, " %u", EXTRACT_32BITS(cp)));
445 		cp += 4;
446 		ND_PRINT((ndo, " %u", EXTRACT_32BITS(cp)));
447 		cp += 4;
448 		ND_PRINT((ndo, " %u", EXTRACT_32BITS(cp)));
449 		cp += 4;
450 		ND_PRINT((ndo, " %u", EXTRACT_32BITS(cp)));
451 		cp += 4;
452 		ND_PRINT((ndo, " %u", EXTRACT_32BITS(cp)));
453 		cp += 4;
454 		break;
455 	case T_MX:
456 		ND_PRINT((ndo, " "));
457 		if (!ND_TTEST2(*cp, 2))
458 			return(NULL);
459 		if (ns_nprint(ndo, cp + 2, bp) == NULL)
460 			return(NULL);
461 		ND_PRINT((ndo, " %d", EXTRACT_16BITS(cp)));
462 		break;
463 
464 	case T_TXT:
465 		while (cp < rp) {
466 			ND_PRINT((ndo, " \""));
467 			cp = ns_cprint(ndo, cp);
468 			if (cp == NULL)
469 				return(NULL);
470 			ND_PRINT((ndo, "\""));
471 		}
472 		break;
473 
474 	case T_SRV:
475 		ND_PRINT((ndo, " "));
476 		if (!ND_TTEST2(*cp, 6))
477 			return(NULL);
478 		if (ns_nprint(ndo, cp + 6, bp) == NULL)
479 			return(NULL);
480 		ND_PRINT((ndo, ":%d %d %d", EXTRACT_16BITS(cp + 4),
481 			EXTRACT_16BITS(cp), EXTRACT_16BITS(cp + 2)));
482 		break;
483 
484 #ifdef INET6
485 	case T_AAAA:
486 	    {
487 		struct in6_addr addr;
488 		char ntop_buf[INET6_ADDRSTRLEN];
489 
490 		if (!ND_TTEST2(*cp, sizeof(struct in6_addr)))
491 			return(NULL);
492 		memcpy(&addr, cp, sizeof(struct in6_addr));
493 		ND_PRINT((ndo, " %s",
494 		    inet_ntop(AF_INET6, &addr, ntop_buf, sizeof(ntop_buf))));
495 
496 		break;
497 	    }
498 
499 	case T_A6:
500 	    {
501 		struct in6_addr a;
502 		int pbit, pbyte;
503 		char ntop_buf[INET6_ADDRSTRLEN];
504 
505 		if (!ND_TTEST2(*cp, 1))
506 			return(NULL);
507 		pbit = *cp;
508 		pbyte = (pbit & ~7) / 8;
509 		if (pbit > 128) {
510 			ND_PRINT((ndo, " %u(bad plen)", pbit));
511 			break;
512 		} else if (pbit < 128) {
513 			if (!ND_TTEST2(*(cp + 1), sizeof(a) - pbyte))
514 				return(NULL);
515 			memset(&a, 0, sizeof(a));
516 			memcpy(&a.s6_addr[pbyte], cp + 1, sizeof(a) - pbyte);
517 			ND_PRINT((ndo, " %u %s", pbit,
518 			    inet_ntop(AF_INET6, &a, ntop_buf, sizeof(ntop_buf))));
519 		}
520 		if (pbit > 0) {
521 			ND_PRINT((ndo, " "));
522 			if (ns_nprint(ndo, cp + 1 + sizeof(a) - pbyte, bp) == NULL)
523 				return(NULL);
524 		}
525 		break;
526 	    }
527 #endif /*INET6*/
528 
529 	case T_OPT:
530 		ND_PRINT((ndo, " UDPsize=%u", class));
531 		if (opt_flags & 0x8000)
532 			ND_PRINT((ndo, " OK"));
533 		break;
534 
535 	case T_UNSPECA:		/* One long string */
536 		if (!ND_TTEST2(*cp, len))
537 			return(NULL);
538 		if (fn_printn(ndo, cp, len, ndo->ndo_snapend))
539 			return(NULL);
540 		break;
541 
542 	case T_TSIG:
543 	    {
544 		if (cp + len > ndo->ndo_snapend)
545 			return(NULL);
546 		if (!ndo->ndo_vflag)
547 			break;
548 		ND_PRINT((ndo, " "));
549 		if ((cp = ns_nprint(ndo, cp, bp)) == NULL)
550 			return(NULL);
551 		cp += 6;
552 		if (!ND_TTEST2(*cp, 2))
553 			return(NULL);
554 		ND_PRINT((ndo, " fudge=%u", EXTRACT_16BITS(cp)));
555 		cp += 2;
556 		if (!ND_TTEST2(*cp, 2))
557 			return(NULL);
558 		ND_PRINT((ndo, " maclen=%u", EXTRACT_16BITS(cp)));
559 		cp += 2 + EXTRACT_16BITS(cp);
560 		if (!ND_TTEST2(*cp, 2))
561 			return(NULL);
562 		ND_PRINT((ndo, " origid=%u", EXTRACT_16BITS(cp)));
563 		cp += 2;
564 		if (!ND_TTEST2(*cp, 2))
565 			return(NULL);
566 		ND_PRINT((ndo, " error=%u", EXTRACT_16BITS(cp)));
567 		cp += 2;
568 		if (!ND_TTEST2(*cp, 2))
569 			return(NULL);
570 		ND_PRINT((ndo, " otherlen=%u", EXTRACT_16BITS(cp)));
571 		cp += 2;
572 	    }
573 	}
574 	return (rp);		/* XXX This isn't always right */
575 }
576 
577 void
ns_print(netdissect_options * ndo,register const u_char * bp,u_int length,int is_mdns)578 ns_print(netdissect_options *ndo,
579          register const u_char *bp, u_int length, int is_mdns)
580 {
581 	register const HEADER *np;
582 	register int qdcount, ancount, nscount, arcount;
583 	register const u_char *cp;
584 	uint16_t b2;
585 
586 	np = (const HEADER *)bp;
587 	ND_TCHECK(*np);
588 	/* get the byte-order right */
589 	qdcount = EXTRACT_16BITS(&np->qdcount);
590 	ancount = EXTRACT_16BITS(&np->ancount);
591 	nscount = EXTRACT_16BITS(&np->nscount);
592 	arcount = EXTRACT_16BITS(&np->arcount);
593 
594 	if (DNS_QR(np)) {
595 		/* this is a response */
596 		ND_PRINT((ndo, "%d%s%s%s%s%s%s",
597 			EXTRACT_16BITS(&np->id),
598 			ns_ops[DNS_OPCODE(np)],
599 			ns_resp[DNS_RCODE(np)],
600 			DNS_AA(np)? "*" : "",
601 			DNS_RA(np)? "" : "-",
602 			DNS_TC(np)? "|" : "",
603 			DNS_AD(np)? "$" : ""));
604 
605 		if (qdcount != 1)
606 			ND_PRINT((ndo, " [%dq]", qdcount));
607 		/* Print QUESTION section on -vv */
608 		cp = (const u_char *)(np + 1);
609 		while (qdcount--) {
610 			if (qdcount < EXTRACT_16BITS(&np->qdcount) - 1)
611 				ND_PRINT((ndo, ","));
612 			if (ndo->ndo_vflag > 1) {
613 				ND_PRINT((ndo, " q:"));
614 				if ((cp = ns_qprint(ndo, cp, bp, is_mdns)) == NULL)
615 					goto trunc;
616 			} else {
617 				if ((cp = ns_nskip(ndo, cp)) == NULL)
618 					goto trunc;
619 				cp += 4;	/* skip QTYPE and QCLASS */
620 			}
621 		}
622 		ND_PRINT((ndo, " %d/%d/%d", ancount, nscount, arcount));
623 		if (ancount--) {
624 			if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
625 				goto trunc;
626 			while (cp < ndo->ndo_snapend && ancount--) {
627 				ND_PRINT((ndo, ","));
628 				if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
629 					goto trunc;
630 			}
631 		}
632 		if (ancount > 0)
633 			goto trunc;
634 		/* Print NS and AR sections on -vv */
635 		if (ndo->ndo_vflag > 1) {
636 			if (cp < ndo->ndo_snapend && nscount--) {
637 				ND_PRINT((ndo, " ns:"));
638 				if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
639 					goto trunc;
640 				while (cp < ndo->ndo_snapend && nscount--) {
641 					ND_PRINT((ndo, ","));
642 					if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
643 						goto trunc;
644 				}
645 			}
646 			if (nscount > 0)
647 				goto trunc;
648 			if (cp < ndo->ndo_snapend && arcount--) {
649 				ND_PRINT((ndo, " ar:"));
650 				if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
651 					goto trunc;
652 				while (cp < ndo->ndo_snapend && arcount--) {
653 					ND_PRINT((ndo, ","));
654 					if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
655 						goto trunc;
656 				}
657 			}
658 			if (arcount > 0)
659 				goto trunc;
660 		}
661 	}
662 	else {
663 		/* this is a request */
664 		ND_PRINT((ndo, "%d%s%s%s", EXTRACT_16BITS(&np->id), ns_ops[DNS_OPCODE(np)],
665 		    DNS_RD(np) ? "+" : "",
666 		    DNS_CD(np) ? "%" : ""));
667 
668 		/* any weirdness? */
669 		b2 = EXTRACT_16BITS(((u_short *)np)+1);
670 		if (b2 & 0x6cf)
671 			ND_PRINT((ndo, " [b2&3=0x%x]", b2));
672 
673 		if (DNS_OPCODE(np) == IQUERY) {
674 			if (qdcount)
675 				ND_PRINT((ndo, " [%dq]", qdcount));
676 			if (ancount != 1)
677 				ND_PRINT((ndo, " [%da]", ancount));
678 		}
679 		else {
680 			if (ancount)
681 				ND_PRINT((ndo, " [%da]", ancount));
682 			if (qdcount != 1)
683 				ND_PRINT((ndo, " [%dq]", qdcount));
684 		}
685 		if (nscount)
686 			ND_PRINT((ndo, " [%dn]", nscount));
687 		if (arcount)
688 			ND_PRINT((ndo, " [%dau]", arcount));
689 
690 		cp = (const u_char *)(np + 1);
691 		if (qdcount--) {
692 			cp = ns_qprint(ndo, cp, (const u_char *)np, is_mdns);
693 			if (!cp)
694 				goto trunc;
695 			while (cp < ndo->ndo_snapend && qdcount--) {
696 				cp = ns_qprint(ndo, (const u_char *)cp,
697 					       (const u_char *)np,
698 					       is_mdns);
699 				if (!cp)
700 					goto trunc;
701 			}
702 		}
703 		if (qdcount > 0)
704 			goto trunc;
705 
706 		/* Print remaining sections on -vv */
707 		if (ndo->ndo_vflag > 1) {
708 			if (ancount--) {
709 				if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
710 					goto trunc;
711 				while (cp < ndo->ndo_snapend && ancount--) {
712 					ND_PRINT((ndo, ","));
713 					if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
714 						goto trunc;
715 				}
716 			}
717 			if (ancount > 0)
718 				goto trunc;
719 			if (cp < ndo->ndo_snapend && nscount--) {
720 				ND_PRINT((ndo, " ns:"));
721 				if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
722 					goto trunc;
723 				while (nscount-- && cp < ndo->ndo_snapend) {
724 					ND_PRINT((ndo, ","));
725 					if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
726 						goto trunc;
727 				}
728 			}
729 			if (nscount > 0)
730 				goto trunc;
731 			if (cp < ndo->ndo_snapend && arcount--) {
732 				ND_PRINT((ndo, " ar:"));
733 				if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
734 					goto trunc;
735 				while (cp < ndo->ndo_snapend && arcount--) {
736 					ND_PRINT((ndo, ","));
737 					if ((cp = ns_rprint(ndo, cp, bp, is_mdns)) == NULL)
738 						goto trunc;
739 				}
740 			}
741 			if (arcount > 0)
742 				goto trunc;
743 		}
744 	}
745 	ND_PRINT((ndo, " (%d)", length));
746 	return;
747 
748   trunc:
749 	ND_PRINT((ndo, "[|domain]"));
750 }
751