xref: /freebsd/contrib/tcpdump/print-domain.c (revision 74bf4e164ba5851606a27d4feff27717452583e5) 
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  * $FreeBSD$
22  */
23 
24 #ifndef lint
25 static const char rcsid[] _U_ =
26     "@(#) $Header: /tcpdump/master/tcpdump/print-domain.c,v 1.86.2.3 2004/03/28 20:54:00 fenner Exp $ (LBL)";
27 #endif
28 
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32 
33 #include <tcpdump-stdinc.h>
34 
35 #include "nameser.h"
36 
37 #include <stdio.h>
38 #include <string.h>
39 
40 #include "interface.h"
41 #include "addrtoname.h"
42 #include "extract.h"                    /* must come after interface.h */
43 
44 static const char *ns_ops[] = {
45 	"", " inv_q", " stat", " op3", " notify", " update", " op6", " op7",
46 	" op8", " updataA", " updateD", " updateDA",
47 	" updateM", " updateMA", " zoneInit", " zoneRef",
48 };
49 
50 static const char *ns_resp[] = {
51 	"", " FormErr", " ServFail", " NXDomain",
52 	" NotImp", " Refused", " YXDomain", " YXRRSet",
53 	" NXRRSet", " NotAuth", " NotZone", " Resp11",
54 	" Resp12", " Resp13", " Resp14", " NoChange",
55 };
56 
57 /* skip over a domain name */
58 static const u_char *
59 ns_nskip(register const u_char *cp)
60 {
61 	register u_char i;
62 
63 	if (!TTEST2(*cp, 1))
64 		return (NULL);
65 	i = *cp++;
66 	while (i) {
67 		if ((i & INDIR_MASK) == INDIR_MASK)
68 			return (cp + 1);
69 		if ((i & INDIR_MASK) == EDNS0_MASK) {
70 			int bitlen, bytelen;
71 
72 			if ((i & ~INDIR_MASK) != EDNS0_ELT_BITLABEL)
73 				return(NULL); /* unknown ELT */
74 			if (!TTEST2(*cp, 1))
75 				return (NULL);
76 			if ((bitlen = *cp++) == 0)
77 				bitlen = 256;
78 			bytelen = (bitlen + 7) / 8;
79 			cp += bytelen;
80 		} else
81 			cp += i;
82 		if (!TTEST2(*cp, 1))
83 			return (NULL);
84 		i = *cp++;
85 	}
86 	return (cp);
87 }
88 
89 /* print a <domain-name> */
90 static const u_char *
91 blabel_print(const u_char *cp)
92 {
93 	int bitlen, slen, b;
94 	const u_char *bitp, *lim;
95 	char tc;
96 
97 	if (!TTEST2(*cp, 1))
98 		return(NULL);
99 	if ((bitlen = *cp) == 0)
100 		bitlen = 256;
101 	slen = (bitlen + 3) / 4;
102 	lim = cp + 1 + slen;
103 
104 	/* print the bit string as a hex string */
105 	printf("\\[x");
106 	for (bitp = cp + 1, b = bitlen; bitp < lim && b > 7; b -= 8, bitp++) {
107 		TCHECK(*bitp);
108 		printf("%02x", *bitp);
109 	}
110 	if (b > 4) {
111 		TCHECK(*bitp);
112 		tc = *bitp++;
113 		printf("%02x", tc & (0xff << (8 - b)));
114 	} else if (b > 0) {
115 		TCHECK(*bitp);
116 		tc = *bitp++;
117 		printf("%1x", ((tc >> 4) & 0x0f) & (0x0f << (4 - b)));
118 	}
119 	printf("/%d]", bitlen);
120 	return lim;
121 trunc:
122 	printf(".../%d]", bitlen);
123 	return NULL;
124 }
125 
126 static int
127 labellen(const u_char *cp)
128 {
129 	register u_int i;
130 
131 	if (!TTEST2(*cp, 1))
132 		return(-1);
133 	i = *cp;
134 	if ((i & INDIR_MASK) == EDNS0_MASK) {
135 		int bitlen, elt;
136 
137 		if ((elt = (i & ~INDIR_MASK)) != EDNS0_ELT_BITLABEL)
138 			return(-1);
139 		if (!TTEST2(*(cp + 1), 1))
140 			return(-1);
141 		if ((bitlen = *(cp + 1)) == 0)
142 			bitlen = 256;
143 		return(((bitlen + 7) / 8) + 1);
144 	} else
145 		return(i);
146 }
147 
148 static const u_char *
149 ns_nprint(register const u_char *cp, register const u_char *bp)
150 {
151 	register u_int i, l;
152 	register const u_char *rp = NULL;
153 	register int compress = 0;
154 	int chars_processed;
155 	int elt;
156 	int data_size = snapend - bp;
157 
158 	if ((l = labellen(cp)) == (u_int)-1)
159 		return(NULL);
160 	if (!TTEST2(*cp, 1))
161 		return(NULL);
162 	chars_processed = 1;
163 	if (((i = *cp++) & INDIR_MASK) != INDIR_MASK) {
164 		compress = 0;
165 		rp = cp + l;
166 	}
167 
168 	if (i != 0)
169 		while (i && cp < snapend) {
170 			if ((i & INDIR_MASK) == INDIR_MASK) {
171 				if (!compress) {
172 					rp = cp + 1;
173 					compress = 1;
174 				}
175 				if (!TTEST2(*cp, 1))
176 					return(NULL);
177 				cp = bp + (((i << 8) | *cp) & 0x3fff);
178 				if ((l = labellen(cp)) == (u_int)-1)
179 					return(NULL);
180 				if (!TTEST2(*cp, 1))
181 					return(NULL);
182 				i = *cp++;
183 				chars_processed++;
184 
185 				/*
186 				 * If we've looked at every character in
187 				 * the message, this pointer will make
188 				 * us look at some character again,
189 				 * which means we're looping.
190 				 */
191 				if (chars_processed >= data_size) {
192 					printf("<LOOP>");
193 					return (NULL);
194 				}
195 				continue;
196 			}
197 			if ((i & INDIR_MASK) == EDNS0_MASK) {
198 				elt = (i & ~INDIR_MASK);
199 				switch(elt) {
200 				case EDNS0_ELT_BITLABEL:
201 					if (blabel_print(cp) == NULL)
202 						return (NULL);
203 					break;
204 				default:
205 					/* unknown ELT */
206 					printf("<ELT %d>", elt);
207 					return(NULL);
208 				}
209 			} else {
210 				if (fn_printn(cp, l, snapend))
211 					return(NULL);
212 			}
213 
214 			cp += l;
215 			chars_processed += l;
216 			putchar('.');
217 			if ((l = labellen(cp)) == (u_int)-1)
218 				return(NULL);
219 			if (!TTEST2(*cp, 1))
220 				return(NULL);
221 			i = *cp++;
222 			chars_processed++;
223 			if (!compress)
224 				rp += l + 1;
225 		}
226 	else
227 		putchar('.');
228 	return (rp);
229 }
230 
231 /* print a <character-string> */
232 static const u_char *
233 ns_cprint(register const u_char *cp)
234 {
235 	register u_int i;
236 
237 	if (!TTEST2(*cp, 1))
238 		return (NULL);
239 	i = *cp++;
240 	if (fn_printn(cp, i, snapend))
241 		return (NULL);
242 	return (cp + i);
243 }
244 
245 /* http://www.iana.org/assignments/dns-parameters */
246 struct tok ns_type2str[] = {
247 	{ T_A,		"A" },			/* RFC 1035 */
248 	{ T_NS,		"NS" },			/* RFC 1035 */
249 	{ T_MD,		"MD" },			/* RFC 1035 */
250 	{ T_MF,		"MF" },			/* RFC 1035 */
251 	{ T_CNAME,	"CNAME" },		/* RFC 1035 */
252 	{ T_SOA,	"SOA" },		/* RFC 1035 */
253 	{ T_MB,		"MB" },			/* RFC 1035 */
254 	{ T_MG,		"MG" },			/* RFC 1035 */
255 	{ T_MR,		"MR" },			/* RFC 1035 */
256 	{ T_NULL,	"NULL" },		/* RFC 1035 */
257 	{ T_WKS,	"WKS" },		/* RFC 1035 */
258 	{ T_PTR,	"PTR" },		/* RFC 1035 */
259 	{ T_HINFO,	"HINFO" },		/* RFC 1035 */
260 	{ T_MINFO,	"MINFO" },		/* RFC 1035 */
261 	{ T_MX,		"MX" },			/* RFC 1035 */
262 	{ T_TXT,	"TXT" },		/* RFC 1035 */
263 	{ T_RP,		"RP" },			/* RFC 1183 */
264 	{ T_AFSDB,	"AFSDB" },		/* RFC 1183 */
265 	{ T_X25,	"X25" },		/* RFC 1183 */
266 	{ T_ISDN,	"ISDN" },		/* RFC 1183 */
267 	{ T_RT,		"RT" },			/* RFC 1183 */
268 	{ T_NSAP,	"NSAP" },		/* RFC 1706 */
269 	{ T_NSAP_PTR,	"NSAP_PTR" },
270 	{ T_SIG,	"SIG" },		/* RFC 2535 */
271 	{ T_KEY,	"KEY" },		/* RFC 2535 */
272 	{ T_PX,		"PX" },			/* RFC 2163 */
273 	{ T_GPOS,	"GPOS" },		/* RFC 1712 */
274 	{ T_AAAA,	"AAAA" },		/* RFC 1886 */
275 	{ T_LOC,	"LOC" },		/* RFC 1876 */
276 	{ T_NXT,	"NXT" },		/* RFC 2535 */
277 	{ T_EID,	"EID" },		/* Nimrod */
278 	{ T_NIMLOC,	"NIMLOC" },		/* Nimrod */
279 	{ T_SRV,	"SRV" },		/* RFC 2782 */
280 	{ T_ATMA,	"ATMA" },		/* ATM Forum */
281 	{ T_NAPTR,	"NAPTR" },		/* RFC 2168, RFC 2915 */
282 	{ T_A6,		"A6" },			/* RFC 2874 */
283 	{ T_DNAME,	"DNAME" },		/* RFC 2672 */
284 	{ T_OPT,	"OPT" },		/* RFC 2671 */
285 	{ T_UINFO,	"UINFO" },
286 	{ T_UID,	"UID" },
287 	{ T_GID,	"GID" },
288 	{ T_UNSPEC,	"UNSPEC" },
289 	{ T_UNSPECA,	"UNSPECA" },
290 	{ T_TKEY,	"TKEY" },		/* RFC 2930 */
291 	{ T_TSIG,	"TSIG" },		/* RFC 2845 */
292 	{ T_IXFR,	"IXFR" },		/* RFC 1995 */
293 	{ T_AXFR,	"AXFR" },		/* RFC 1035 */
294 	{ T_MAILB,	"MAILB" },		/* RFC 1035 */
295 	{ T_MAILA,	"MAILA" },		/* RFC 1035 */
296 	{ T_ANY,	"ANY" },
297 	{ 0,		NULL }
298 };
299 
300 struct tok ns_class2str[] = {
301 	{ C_IN,		"IN" },		/* Not used */
302 	{ C_CHAOS,	"CHAOS" },
303 	{ C_HS,		"HS" },
304 	{ C_ANY,	"ANY" },
305 	{ 0,		NULL }
306 };
307 
308 /* print a query */
309 static const u_char *
310 ns_qprint(register const u_char *cp, register const u_char *bp, int is_mdns)
311 {
312 	register const u_char *np = cp;
313 	register u_int i;
314 
315 	cp = ns_nskip(cp);
316 
317 	if (cp == NULL || !TTEST2(*cp, 4))
318 		return(NULL);
319 
320 	/* print the qtype and qclass (if it's not IN) */
321 	i = EXTRACT_16BITS(cp);
322 	cp += 2;
323 	printf(" %s", tok2str(ns_type2str, "Type%d", i));
324 	i = EXTRACT_16BITS(cp);
325 	cp += 2;
326 	if (is_mdns && i == (C_IN|C_CACHE_FLUSH))
327 		printf(" (Cache flush)");
328 	else if (i != C_IN)
329 		printf(" %s", tok2str(ns_class2str, "(Class %d)", i));
330 
331 	fputs("? ", stdout);
332 	cp = ns_nprint(np, bp);
333 	return(cp ? cp + 4 : NULL);
334 }
335 
336 /* print a reply */
337 static const u_char *
338 ns_rprint(register const u_char *cp, register const u_char *bp, int is_mdns)
339 {
340 	register u_int class;
341 	register u_short typ, len;
342 	register const u_char *rp;
343 
344 	if (vflag) {
345 		putchar(' ');
346 		if ((cp = ns_nprint(cp, bp)) == NULL)
347 			return NULL;
348 	} else
349 		cp = ns_nskip(cp);
350 
351 	if (cp == NULL || !TTEST2(*cp, 10))
352 		return (snapend);
353 
354 	/* print the type/qtype and class (if it's not IN) */
355 	typ = EXTRACT_16BITS(cp);
356 	cp += 2;
357 	class = EXTRACT_16BITS(cp);
358 	cp += 2;
359 	if (is_mdns && class == (C_IN|C_CACHE_FLUSH))
360 		printf(" (Cache flush)");
361 	else if (class != C_IN && typ != T_OPT)
362 		printf(" %s", tok2str(ns_class2str, "(Class %d)", class));
363 
364 	/* ignore ttl */
365 	cp += 4;
366 
367 	len = EXTRACT_16BITS(cp);
368 	cp += 2;
369 
370 	rp = cp + len;
371 
372 	printf(" %s", tok2str(ns_type2str, "Type%d", typ));
373 	if (rp > snapend)
374 		return(NULL);
375 
376 	switch (typ) {
377 	case T_A:
378 		if (!TTEST2(*cp, sizeof(struct in_addr)))
379 			return(NULL);
380 		printf(" %s", ipaddr_string(cp));
381 		break;
382 
383 	case T_NS:
384 	case T_CNAME:
385 	case T_PTR:
386 #ifdef T_DNAME
387 	case T_DNAME:
388 #endif
389 		putchar(' ');
390 		if (ns_nprint(cp, bp) == NULL)
391 			return(NULL);
392 		break;
393 
394 	case T_SOA:
395 		if (!vflag)
396 			break;
397 		putchar(' ');
398 		if ((cp = ns_nprint(cp, bp)) == NULL)
399 			return(NULL);
400 		putchar(' ');
401 		if ((cp = ns_nprint(cp, bp)) == NULL)
402 			return(NULL);
403 		if (!TTEST2(*cp, 5 * 4))
404 			return(NULL);
405 		printf(" %u", EXTRACT_32BITS(cp));
406 		cp += 4;
407 		printf(" %u", EXTRACT_32BITS(cp));
408 		cp += 4;
409 		printf(" %u", EXTRACT_32BITS(cp));
410 		cp += 4;
411 		printf(" %u", EXTRACT_32BITS(cp));
412 		cp += 4;
413 		printf(" %u", EXTRACT_32BITS(cp));
414 		cp += 4;
415 		break;
416 	case T_MX:
417 		putchar(' ');
418 		if (!TTEST2(*cp, 2))
419 			return(NULL);
420 		if (ns_nprint(cp + 2, bp) == NULL)
421 			return(NULL);
422 		printf(" %d", EXTRACT_16BITS(cp));
423 		break;
424 
425 	case T_TXT:
426 		while (cp < rp) {
427 			printf(" \"");
428 			cp = ns_cprint(cp);
429 			if (cp == NULL)
430 				return(NULL);
431 			putchar('"');
432 		}
433 		break;
434 
435 	case T_SRV:
436 		putchar(' ');
437 		if (!TTEST2(*cp, 6))
438 			return(NULL);
439 		if (ns_nprint(cp + 6, bp) == NULL)
440 			return(NULL);
441 		printf(":%d %d %d", EXTRACT_16BITS(cp + 4),
442 			EXTRACT_16BITS(cp), EXTRACT_16BITS(cp + 2));
443 		break;
444 
445 #ifdef INET6
446 	case T_AAAA:
447 		if (!TTEST2(*cp, sizeof(struct in6_addr)))
448 			return(NULL);
449 		printf(" %s", ip6addr_string(cp));
450 		break;
451 
452 	case T_A6:
453 	    {
454 		struct in6_addr a;
455 		int pbit, pbyte;
456 
457 		if (!TTEST2(*cp, 1))
458 			return(NULL);
459 		pbit = *cp;
460 		pbyte = (pbit & ~7) / 8;
461 		if (pbit > 128) {
462 			printf(" %u(bad plen)", pbit);
463 			break;
464 		} else if (pbit < 128) {
465 			if (!TTEST2(*(cp + 1), sizeof(a) - pbyte))
466 				return(NULL);
467 			memset(&a, 0, sizeof(a));
468 			memcpy(&a.s6_addr[pbyte], cp + 1, sizeof(a) - pbyte);
469 			printf(" %u %s", pbit, ip6addr_string(&a));
470 		}
471 		if (pbit > 0) {
472 			putchar(' ');
473 			if (ns_nprint(cp + 1 + sizeof(a) - pbyte, bp) == NULL)
474 				return(NULL);
475 		}
476 		break;
477 	    }
478 #endif /*INET6*/
479 
480 	case T_OPT:
481 		printf(" UDPsize=%u", class);
482 		break;
483 
484 	case T_UNSPECA:		/* One long string */
485 		if (!TTEST2(*cp, len))
486 			return(NULL);
487 		if (fn_printn(cp, len, snapend))
488 			return(NULL);
489 		break;
490 
491 	case T_TSIG:
492 	    {
493 		if (cp + len > snapend)
494 			return(NULL);
495 		if (!vflag)
496 			break;
497 		putchar(' ');
498 		if ((cp = ns_nprint(cp, bp)) == NULL)
499 			return(NULL);
500 		cp += 6;
501 		if (!TTEST2(*cp, 2))
502 			return(NULL);
503 		printf(" fudge=%u", EXTRACT_16BITS(cp));
504 		cp += 2;
505 		if (!TTEST2(*cp, 2))
506 			return(NULL);
507 		printf(" maclen=%u", EXTRACT_16BITS(cp));
508 		cp += 2 + EXTRACT_16BITS(cp);
509 		if (!TTEST2(*cp, 2))
510 			return(NULL);
511 		printf(" origid=%u", EXTRACT_16BITS(cp));
512 		cp += 2;
513 		if (!TTEST2(*cp, 2))
514 			return(NULL);
515 		printf(" error=%u", EXTRACT_16BITS(cp));
516 		cp += 2;
517 		if (!TTEST2(*cp, 2))
518 			return(NULL);
519 		printf(" otherlen=%u", EXTRACT_16BITS(cp));
520 		cp += 2;
521 	    }
522 	}
523 	return (rp);		/* XXX This isn't always right */
524 }
525 
526 void
527 ns_print(register const u_char *bp, u_int length, int is_mdns)
528 {
529 	register const HEADER *np;
530 	register int qdcount, ancount, nscount, arcount;
531 	register const u_char *cp;
532 	u_int16_t b2;
533 
534 	np = (const HEADER *)bp;
535 	TCHECK(*np);
536 	/* get the byte-order right */
537 	qdcount = EXTRACT_16BITS(&np->qdcount);
538 	ancount = EXTRACT_16BITS(&np->ancount);
539 	nscount = EXTRACT_16BITS(&np->nscount);
540 	arcount = EXTRACT_16BITS(&np->arcount);
541 
542 	if (DNS_QR(np)) {
543 		/* this is a response */
544 		printf(" %d%s%s%s%s%s%s",
545 			EXTRACT_16BITS(&np->id),
546 			ns_ops[DNS_OPCODE(np)],
547 			ns_resp[DNS_RCODE(np)],
548 			DNS_AA(np)? "*" : "",
549 			DNS_RA(np)? "" : "-",
550 			DNS_TC(np)? "|" : "",
551 			DNS_AD(np)? "$" : "");
552 
553 		if (qdcount != 1)
554 			printf(" [%dq]", qdcount);
555 		/* Print QUESTION section on -vv */
556 		cp = (const u_char *)(np + 1);
557 		while (qdcount--) {
558 			if (qdcount < EXTRACT_16BITS(&np->qdcount) - 1)
559 				putchar(',');
560 			if (vflag > 1) {
561 				fputs(" q:", stdout);
562 				if ((cp = ns_qprint(cp, bp, is_mdns)) == NULL)
563 					goto trunc;
564 			} else {
565 				if ((cp = ns_nskip(cp)) == NULL)
566 					goto trunc;
567 				cp += 4;	/* skip QTYPE and QCLASS */
568 			}
569 		}
570 		printf(" %d/%d/%d", ancount, nscount, arcount);
571 		if (ancount--) {
572 			if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
573 				goto trunc;
574 			while (cp < snapend && ancount--) {
575 				putchar(',');
576 				if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
577 					goto trunc;
578 			}
579 		}
580 		if (ancount > 0)
581 			goto trunc;
582 		/* Print NS and AR sections on -vv */
583 		if (vflag > 1) {
584 			if (cp < snapend && nscount--) {
585 				fputs(" ns:", stdout);
586 				if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
587 					goto trunc;
588 				while (cp < snapend && nscount--) {
589 					putchar(',');
590 					if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
591 						goto trunc;
592 				}
593 			}
594 			if (nscount > 0)
595 				goto trunc;
596 			if (cp < snapend && arcount--) {
597 				fputs(" ar:", stdout);
598 				if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
599 					goto trunc;
600 				while (cp < snapend && arcount--) {
601 					putchar(',');
602 					if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
603 						goto trunc;
604 				}
605 			}
606 			if (arcount > 0)
607 				goto trunc;
608 		}
609 	}
610 	else {
611 		/* this is a request */
612 		printf(" %d%s%s%s", EXTRACT_16BITS(&np->id), ns_ops[DNS_OPCODE(np)],
613 		    DNS_RD(np) ? "+" : "",
614 		    DNS_CD(np) ? "%" : "");
615 
616 		/* any weirdness? */
617 		b2 = EXTRACT_16BITS(((u_short *)np)+1);
618 		if (b2 & 0x6cf)
619 			printf(" [b2&3=0x%x]", b2);
620 
621 		if (DNS_OPCODE(np) == IQUERY) {
622 			if (qdcount)
623 				printf(" [%dq]", qdcount);
624 			if (ancount != 1)
625 				printf(" [%da]", ancount);
626 		}
627 		else {
628 			if (ancount)
629 				printf(" [%da]", ancount);
630 			if (qdcount != 1)
631 				printf(" [%dq]", qdcount);
632 		}
633 		if (nscount)
634 			printf(" [%dn]", nscount);
635 		if (arcount)
636 			printf(" [%dau]", arcount);
637 
638 		cp = (const u_char *)(np + 1);
639 		if (qdcount--) {
640 			cp = ns_qprint(cp, (const u_char *)np, is_mdns);
641 			if (!cp)
642 				goto trunc;
643 			while (cp < snapend && qdcount--) {
644 				cp = ns_qprint((const u_char *)cp,
645 					       (const u_char *)np,
646 					       is_mdns);
647 				if (!cp)
648 					goto trunc;
649 			}
650 		}
651 		if (qdcount > 0)
652 			goto trunc;
653 
654 		/* Print remaining sections on -vv */
655 		if (vflag > 1) {
656 			if (ancount--) {
657 				if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
658 					goto trunc;
659 				while (cp < snapend && ancount--) {
660 					putchar(',');
661 					if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
662 						goto trunc;
663 				}
664 			}
665 			if (ancount > 0)
666 				goto trunc;
667 			if (cp < snapend && nscount--) {
668 				fputs(" ns:", stdout);
669 				if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
670 					goto trunc;
671 				while (nscount-- && cp < snapend) {
672 					putchar(',');
673 					if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
674 						goto trunc;
675 				}
676 			}
677 			if (nscount > 0)
678 				goto trunc;
679 			if (cp < snapend && arcount--) {
680 				fputs(" ar:", stdout);
681 				if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
682 					goto trunc;
683 				while (cp < snapend && arcount--) {
684 					putchar(',');
685 					if ((cp = ns_rprint(cp, bp, is_mdns)) == NULL)
686 						goto trunc;
687 				}
688 			}
689 			if (arcount > 0)
690 				goto trunc;
691 		}
692 	}
693 	printf(" (%d)", length);
694 	return;
695 
696   trunc:
697 	printf("[|domain]");
698 	return;
699 }
700