xref: /illumos-gate/usr/src/lib/libresolv2/common/nameser/ns_print.c (revision 5ac95da7d61660aa299c287a39277cb0372be959)
1 /*
2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (c) 1996-1999 by Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include "port_before.h"
19 
20 #include <sys/types.h>
21 #include <sys/socket.h>
22 
23 #include <netinet/in.h>
24 #include <arpa/nameser.h>
25 #include <arpa/inet.h>
26 
27 #include <isc/assertions.h>
28 #include <isc/dst.h>
29 #include <errno.h>
30 #include <resolv.h>
31 #include <string.h>
32 #include <ctype.h>
33 
34 #include "port_after.h"
35 
36 #ifdef SPRINTF_CHAR
37 # define SPRINTF(x) strlen(sprintf/**/x)
38 #else
39 # define SPRINTF(x) ((size_t)sprintf x)
40 #endif
41 
42 /* Forward. */
43 
44 static size_t	prune_origin(const char *name, const char *origin);
45 static int	charstr(const u_char *rdata, const u_char *edata,
46 			char **buf, size_t *buflen);
47 static int	addname(const u_char *msg, size_t msglen,
48 			const u_char **p, const char *origin,
49 			char **buf, size_t *buflen);
50 static void	addlen(size_t len, char **buf, size_t *buflen);
51 static int	addstr(const char *src, size_t len,
52 		       char **buf, size_t *buflen);
53 static int	addtab(size_t len, size_t target, int spaced,
54 		       char **buf, size_t *buflen);
55 
56 /* Macros. */
57 
58 #define	T(x) \
59 	do { \
60 		if ((x) < 0) \
61 			return (-1); \
62 	} while (0)
63 
64 static const char base32hex[] =
65         "0123456789ABCDEFGHIJKLMNOPQRSTUV=0123456789abcdefghijklmnopqrstuv";
66 
67 /* Public. */
68 
69 /*%
70  *	Convert an RR to presentation format.
71  *
72  * return:
73  *\li	Number of characters written to buf, or -1 (check errno).
74  */
75 int
76 ns_sprintrr(const ns_msg *handle, const ns_rr *rr,
77 	    const char *name_ctx, const char *origin,
78 	    char *buf, size_t buflen)
79 {
80 	int n;
81 
82 	n = ns_sprintrrf(ns_msg_base(*handle), ns_msg_size(*handle),
83 			 ns_rr_name(*rr), ns_rr_class(*rr), ns_rr_type(*rr),
84 			 ns_rr_ttl(*rr), ns_rr_rdata(*rr), ns_rr_rdlen(*rr),
85 			 name_ctx, origin, buf, buflen);
86 	return (n);
87 }
88 
89 /*%
90  *	Convert the fields of an RR into presentation format.
91  *
92  * return:
93  *\li	Number of characters written to buf, or -1 (check errno).
94  */
95 int
96 ns_sprintrrf(const u_char *msg, size_t msglen,
97 	    const char *name, ns_class class, ns_type type,
98 	    u_long ttl, const u_char *rdata, size_t rdlen,
99 	    const char *name_ctx, const char *origin,
100 	    char *buf, size_t buflen)
101 {
102 	const char *obuf = buf;
103 	const u_char *edata = rdata + rdlen;
104 	int spaced = 0;
105 
106 	const char *comment;
107 	char tmp[100];
108 	int len, x;
109 
110 	/*
111 	 * Owner.
112 	 */
113 	if (name_ctx != NULL && ns_samename(name_ctx, name) == 1) {
114 		T(addstr("\t\t\t", 3, &buf, &buflen));
115 	} else {
116 		len = prune_origin(name, origin);
117 		if (*name == '\0') {
118 			goto root;
119 		} else if (len == 0) {
120 			T(addstr("@\t\t\t", 4, &buf, &buflen));
121 		} else {
122 			T(addstr(name, len, &buf, &buflen));
123 			/* Origin not used or not root, and no trailing dot? */
124 			if (((origin == NULL || origin[0] == '\0') ||
125 			    (origin[0] != '.' && origin[1] != '\0' &&
126 			    name[len] == '\0')) && name[len - 1] != '.') {
127  root:
128 				T(addstr(".", 1, &buf, &buflen));
129 				len++;
130 			}
131 			T(spaced = addtab(len, 24, spaced, &buf, &buflen));
132 		}
133 	}
134 
135 	/*
136 	 * TTL, Class, Type.
137 	 */
138 	T(x = ns_format_ttl(ttl, buf, buflen));
139 	addlen(x, &buf, &buflen);
140 	len = SPRINTF((tmp, " %s %s", p_class(class), p_type(type)));
141 	T(addstr(tmp, len, &buf, &buflen));
142 	T(spaced = addtab(x + len, 16, spaced, &buf, &buflen));
143 
144 	/*
145 	 * RData.
146 	 */
147 	switch (type) {
148 	case ns_t_a:
149 		if (rdlen != (size_t)NS_INADDRSZ)
150 			goto formerr;
151 		(void) inet_ntop(AF_INET, rdata, buf, buflen);
152 		addlen(strlen(buf), &buf, &buflen);
153 		break;
154 
155 	case ns_t_cname:
156 	case ns_t_mb:
157 	case ns_t_mg:
158 	case ns_t_mr:
159 	case ns_t_ns:
160 	case ns_t_ptr:
161 	case ns_t_dname:
162 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
163 		break;
164 
165 	case ns_t_hinfo:
166 	case ns_t_isdn:
167 		/* First word. */
168 		T(len = charstr(rdata, edata, &buf, &buflen));
169 		if (len == 0)
170 			goto formerr;
171 		rdata += len;
172 		T(addstr(" ", 1, &buf, &buflen));
173 
174 
175 		/* Second word, optional in ISDN records. */
176 		if (type == ns_t_isdn && rdata == edata)
177 			break;
178 
179 		T(len = charstr(rdata, edata, &buf, &buflen));
180 		if (len == 0)
181 			goto formerr;
182 		rdata += len;
183 		break;
184 
185 	case ns_t_soa: {
186 		u_long t;
187 
188 		/* Server name. */
189 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
190 		T(addstr(" ", 1, &buf, &buflen));
191 
192 		/* Administrator name. */
193 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
194 		T(addstr(" (\n", 3, &buf, &buflen));
195 		spaced = 0;
196 
197 		if ((edata - rdata) != 5*NS_INT32SZ)
198 			goto formerr;
199 
200 		/* Serial number. */
201 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
202 		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
203 		len = SPRINTF((tmp, "%lu", t));
204 		T(addstr(tmp, len, &buf, &buflen));
205 		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
206 		T(addstr("; serial\n", 9, &buf, &buflen));
207 		spaced = 0;
208 
209 		/* Refresh interval. */
210 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
211 		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
212 		T(len = ns_format_ttl(t, buf, buflen));
213 		addlen(len, &buf, &buflen);
214 		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
215 		T(addstr("; refresh\n", 10, &buf, &buflen));
216 		spaced = 0;
217 
218 		/* Retry interval. */
219 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
220 		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
221 		T(len = ns_format_ttl(t, buf, buflen));
222 		addlen(len, &buf, &buflen);
223 		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
224 		T(addstr("; retry\n", 8, &buf, &buflen));
225 		spaced = 0;
226 
227 		/* Expiry. */
228 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
229 		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
230 		T(len = ns_format_ttl(t, buf, buflen));
231 		addlen(len, &buf, &buflen);
232 		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
233 		T(addstr("; expiry\n", 9, &buf, &buflen));
234 		spaced = 0;
235 
236 		/* Minimum TTL. */
237 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
238 		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
239 		T(len = ns_format_ttl(t, buf, buflen));
240 		addlen(len, &buf, &buflen);
241 		T(addstr(" )", 2, &buf, &buflen));
242 		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
243 		T(addstr("; minimum\n", 10, &buf, &buflen));
244 
245 		break;
246 	    }
247 
248 	case ns_t_mx:
249 	case ns_t_afsdb:
250 	case ns_t_rt:
251 	case ns_t_kx: {
252 		u_int t;
253 
254 		if (rdlen < (size_t)NS_INT16SZ)
255 			goto formerr;
256 
257 		/* Priority. */
258 		t = ns_get16(rdata);
259 		rdata += NS_INT16SZ;
260 		len = SPRINTF((tmp, "%u ", t));
261 		T(addstr(tmp, len, &buf, &buflen));
262 
263 		/* Target. */
264 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
265 
266 		break;
267 	    }
268 
269 	case ns_t_px: {
270 		u_int t;
271 
272 		if (rdlen < (size_t)NS_INT16SZ)
273 			goto formerr;
274 
275 		/* Priority. */
276 		t = ns_get16(rdata);
277 		rdata += NS_INT16SZ;
278 		len = SPRINTF((tmp, "%u ", t));
279 		T(addstr(tmp, len, &buf, &buflen));
280 
281 		/* Name1. */
282 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
283 		T(addstr(" ", 1, &buf, &buflen));
284 
285 		/* Name2. */
286 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
287 
288 		break;
289 	    }
290 
291 	case ns_t_x25:
292 		T(len = charstr(rdata, edata, &buf, &buflen));
293 		if (len == 0)
294 			goto formerr;
295 		rdata += len;
296 		break;
297 
298 	case ns_t_txt:
299 	case ns_t_spf:
300 		while (rdata < edata) {
301 			T(len = charstr(rdata, edata, &buf, &buflen));
302 			if (len == 0)
303 				goto formerr;
304 			rdata += len;
305 			if (rdata < edata)
306 				T(addstr(" ", 1, &buf, &buflen));
307 		}
308 		break;
309 
310 	case ns_t_nsap: {
311 		char t[2+255*3];
312 
313 		(void) inet_nsap_ntoa(rdlen, rdata, t);
314 		T(addstr(t, strlen(t), &buf, &buflen));
315 		break;
316 	    }
317 
318 	case ns_t_aaaa:
319 		if (rdlen != (size_t)NS_IN6ADDRSZ)
320 			goto formerr;
321 		(void) inet_ntop(AF_INET6, rdata, buf, buflen);
322 		addlen(strlen(buf), &buf, &buflen);
323 		break;
324 
325 	case ns_t_loc: {
326 		char t[255];
327 
328 		/* XXX protocol format checking? */
329 		(void) loc_ntoa(rdata, t);
330 		T(addstr(t, strlen(t), &buf, &buflen));
331 		break;
332 	    }
333 
334 	case ns_t_naptr: {
335 		u_int order, preference;
336 		char t[50];
337 
338 		if (rdlen < 2U*NS_INT16SZ)
339 			goto formerr;
340 
341 		/* Order, Precedence. */
342 		order = ns_get16(rdata);	rdata += NS_INT16SZ;
343 		preference = ns_get16(rdata);	rdata += NS_INT16SZ;
344 		len = SPRINTF((t, "%u %u ", order, preference));
345 		T(addstr(t, len, &buf, &buflen));
346 
347 		/* Flags. */
348 		T(len = charstr(rdata, edata, &buf, &buflen));
349 		if (len == 0)
350 			goto formerr;
351 		rdata += len;
352 		T(addstr(" ", 1, &buf, &buflen));
353 
354 		/* Service. */
355 		T(len = charstr(rdata, edata, &buf, &buflen));
356 		if (len == 0)
357 			goto formerr;
358 		rdata += len;
359 		T(addstr(" ", 1, &buf, &buflen));
360 
361 		/* Regexp. */
362 		T(len = charstr(rdata, edata, &buf, &buflen));
363 		if (len < 0)
364 			return (-1);
365 		if (len == 0)
366 			goto formerr;
367 		rdata += len;
368 		T(addstr(" ", 1, &buf, &buflen));
369 
370 		/* Server. */
371 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
372 		break;
373 	    }
374 
375 	case ns_t_srv: {
376 		u_int priority, weight, port;
377 		char t[50];
378 
379 		if (rdlen < 3U*NS_INT16SZ)
380 			goto formerr;
381 
382 		/* Priority, Weight, Port. */
383 		priority = ns_get16(rdata);  rdata += NS_INT16SZ;
384 		weight   = ns_get16(rdata);  rdata += NS_INT16SZ;
385 		port     = ns_get16(rdata);  rdata += NS_INT16SZ;
386 		len = SPRINTF((t, "%u %u %u ", priority, weight, port));
387 		T(addstr(t, len, &buf, &buflen));
388 
389 		/* Server. */
390 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
391 		break;
392 	    }
393 
394 	case ns_t_minfo:
395 	case ns_t_rp:
396 		/* Name1. */
397 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
398 		T(addstr(" ", 1, &buf, &buflen));
399 
400 		/* Name2. */
401 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
402 
403 		break;
404 
405 	case ns_t_wks: {
406 		int n, lcnt;
407 
408 		if (rdlen < 1U + NS_INT32SZ)
409 			goto formerr;
410 
411 		/* Address. */
412 		(void) inet_ntop(AF_INET, rdata, buf, buflen);
413 		addlen(strlen(buf), &buf, &buflen);
414 		rdata += NS_INADDRSZ;
415 
416 		/* Protocol. */
417 		len = SPRINTF((tmp, " %u ( ", *rdata));
418 		T(addstr(tmp, len, &buf, &buflen));
419 		rdata += NS_INT8SZ;
420 
421 		/* Bit map. */
422 		n = 0;
423 		lcnt = 0;
424 		while (rdata < edata) {
425 			u_int c = *rdata++;
426 			do {
427 				if (c & 0200) {
428 					if (lcnt == 0) {
429 						T(addstr("\n\t\t\t\t", 5,
430 							 &buf, &buflen));
431 						lcnt = 10;
432 						spaced = 0;
433 					}
434 					len = SPRINTF((tmp, "%d ", n));
435 					T(addstr(tmp, len, &buf, &buflen));
436 					lcnt--;
437 				}
438 				c <<= 1;
439 			} while (++n & 07);
440 		}
441 		T(addstr(")", 1, &buf, &buflen));
442 
443 		break;
444 	    }
445 
446 	case ns_t_key:
447 	case ns_t_dnskey: {
448 		char base64_key[NS_MD5RSA_MAX_BASE64];
449 		u_int keyflags, protocol, algorithm, key_id;
450 		const char *leader;
451 		int n;
452 
453 		if (rdlen < 0U + NS_INT16SZ + NS_INT8SZ + NS_INT8SZ)
454 			goto formerr;
455 
456 		/* Key flags, Protocol, Algorithm. */
457 		key_id = dst_s_dns_key_id(rdata, edata-rdata);
458 		keyflags = ns_get16(rdata);  rdata += NS_INT16SZ;
459 		protocol = *rdata++;
460 		algorithm = *rdata++;
461 		len = SPRINTF((tmp, "0x%04x %u %u",
462 			       keyflags, protocol, algorithm));
463 		T(addstr(tmp, len, &buf, &buflen));
464 
465 		/* Public key data. */
466 		len = b64_ntop(rdata, edata - rdata,
467 			       base64_key, sizeof base64_key);
468 		if (len < 0)
469 			goto formerr;
470 		if (len > 15) {
471 			T(addstr(" (", 2, &buf, &buflen));
472 			leader = "\n\t\t";
473 			spaced = 0;
474 		} else
475 			leader = " ";
476 		for (n = 0; n < len; n += 48) {
477 			T(addstr(leader, strlen(leader), &buf, &buflen));
478 			T(addstr(base64_key + n, MIN(len - n, 48),
479 				 &buf, &buflen));
480 		}
481 		if (len > 15)
482 			T(addstr(" )", 2, &buf, &buflen));
483 		n = SPRINTF((tmp, " ; key_tag= %u", key_id));
484 		T(addstr(tmp, n, &buf, &buflen));
485 
486 		break;
487 	    }
488 
489 	case ns_t_sig:
490 	case ns_t_rrsig: {
491 		char base64_key[NS_MD5RSA_MAX_BASE64];
492 		u_int type, algorithm, labels, footprint;
493 		const char *leader;
494 		u_long t;
495 		int n;
496 
497 		if (rdlen < 22U)
498 			goto formerr;
499 
500 		/* Type covered, Algorithm, Label count, Original TTL. */
501 		type = ns_get16(rdata);  rdata += NS_INT16SZ;
502 		algorithm = *rdata++;
503 		labels = *rdata++;
504 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
505 		len = SPRINTF((tmp, "%s %d %d %lu ",
506 			       p_type(type), algorithm, labels, t));
507 		T(addstr(tmp, len, &buf, &buflen));
508 		if (labels > (u_int)dn_count_labels(name))
509 			goto formerr;
510 
511 		/* Signature expiry. */
512 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
513 		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
514 		T(addstr(tmp, len, &buf, &buflen));
515 
516 		/* Time signed. */
517 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
518 		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
519 		T(addstr(tmp, len, &buf, &buflen));
520 
521 		/* Signature Footprint. */
522 		footprint = ns_get16(rdata);  rdata += NS_INT16SZ;
523 		len = SPRINTF((tmp, "%u ", footprint));
524 		T(addstr(tmp, len, &buf, &buflen));
525 
526 		/* Signer's name. */
527 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
528 
529 		/* Signature. */
530 		len = b64_ntop(rdata, edata - rdata,
531 			       base64_key, sizeof base64_key);
532 		if (len > 15) {
533 			T(addstr(" (", 2, &buf, &buflen));
534 			leader = "\n\t\t";
535 			spaced = 0;
536 		} else
537 			leader = " ";
538 		if (len < 0)
539 			goto formerr;
540 		for (n = 0; n < len; n += 48) {
541 			T(addstr(leader, strlen(leader), &buf, &buflen));
542 			T(addstr(base64_key + n, MIN(len - n, 48),
543 				 &buf, &buflen));
544 		}
545 		if (len > 15)
546 			T(addstr(" )", 2, &buf, &buflen));
547 		break;
548 	    }
549 
550 	case ns_t_nxt: {
551 		int n, c;
552 
553 		/* Next domain name. */
554 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
555 
556 		/* Type bit map. */
557 		n = edata - rdata;
558 		for (c = 0; c < n*8; c++)
559 			if (NS_NXT_BIT_ISSET(c, rdata)) {
560 				len = SPRINTF((tmp, " %s", p_type(c)));
561 				T(addstr(tmp, len, &buf, &buflen));
562 			}
563 		break;
564 	    }
565 
566 	case ns_t_cert: {
567 		u_int c_type, key_tag, alg;
568 		int n;
569 		unsigned int siz;
570 		char base64_cert[8192], tmp[40];
571 		const char *leader;
572 
573 		c_type  = ns_get16(rdata); rdata += NS_INT16SZ;
574 		key_tag = ns_get16(rdata); rdata += NS_INT16SZ;
575 		alg = (u_int) *rdata++;
576 
577 		len = SPRINTF((tmp, "%d %d %d ", c_type, key_tag, alg));
578 		T(addstr(tmp, len, &buf, &buflen));
579 		siz = (edata-rdata)*4/3 + 4; /* "+4" accounts for trailing \0 */
580 		if (siz > sizeof(base64_cert) * 3/4) {
581 			const char *str = "record too long to print";
582 			T(addstr(str, strlen(str), &buf, &buflen));
583 		}
584 		else {
585 			len = b64_ntop(rdata, edata-rdata, base64_cert, siz);
586 
587 			if (len < 0)
588 				goto formerr;
589 			else if (len > 15) {
590 				T(addstr(" (", 2, &buf, &buflen));
591 				leader = "\n\t\t";
592 				spaced = 0;
593 			}
594 			else
595 				leader = " ";
596 
597 			for (n = 0; n < len; n += 48) {
598 				T(addstr(leader, strlen(leader),
599 					 &buf, &buflen));
600 				T(addstr(base64_cert + n, MIN(len - n, 48),
601 					 &buf, &buflen));
602 			}
603 			if (len > 15)
604 				T(addstr(" )", 2, &buf, &buflen));
605 		}
606 		break;
607 	    }
608 
609 	case ns_t_tkey: {
610 		/* KJD - need to complete this */
611 		u_long t;
612 		int mode, err, keysize;
613 
614 		/* Algorithm name. */
615 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
616 		T(addstr(" ", 1, &buf, &buflen));
617 
618 		/* Inception. */
619 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
620 		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
621 		T(addstr(tmp, len, &buf, &buflen));
622 
623 		/* Experation. */
624 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
625 		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
626 		T(addstr(tmp, len, &buf, &buflen));
627 
628 		/* Mode , Error, Key Size. */
629 		/* Priority, Weight, Port. */
630 		mode = ns_get16(rdata);  rdata += NS_INT16SZ;
631 		err  = ns_get16(rdata);  rdata += NS_INT16SZ;
632 		keysize  = ns_get16(rdata);  rdata += NS_INT16SZ;
633 		len = SPRINTF((tmp, "%u %u %u ", mode, err, keysize));
634 		T(addstr(tmp, len, &buf, &buflen));
635 
636 		/* XXX need to dump key, print otherdata length & other data */
637 		break;
638 	    }
639 
640 	case ns_t_tsig: {
641 		/* BEW - need to complete this */
642 		int n;
643 
644 		T(len = addname(msg, msglen, &rdata, origin, &buf, &buflen));
645 		T(addstr(" ", 1, &buf, &buflen));
646 		rdata += 8; /*%< time */
647 		n = ns_get16(rdata); rdata += INT16SZ;
648 		rdata += n; /*%< sig */
649 		n = ns_get16(rdata); rdata += INT16SZ; /*%< original id */
650 		sprintf(buf, "%d", ns_get16(rdata));
651 		rdata += INT16SZ;
652 		addlen(strlen(buf), &buf, &buflen);
653 		break;
654 	    }
655 
656 	case ns_t_a6: {
657 		struct in6_addr a;
658 		int pbyte, pbit;
659 
660 		/* prefix length */
661 		if (rdlen == 0U) goto formerr;
662 		len = SPRINTF((tmp, "%d ", *rdata));
663 		T(addstr(tmp, len, &buf, &buflen));
664 		pbit = *rdata;
665 		if (pbit > 128) goto formerr;
666 		pbyte = (pbit & ~7) / 8;
667 		rdata++;
668 
669 		/* address suffix: provided only when prefix len != 128 */
670 		if (pbit < 128) {
671 			if (rdata + pbyte >= edata) goto formerr;
672 			memset(&a, 0, sizeof(a));
673 			memcpy(&a.s6_addr[pbyte], rdata, sizeof(a) - pbyte);
674 			(void) inet_ntop(AF_INET6, &a, buf, buflen);
675 			addlen(strlen(buf), &buf, &buflen);
676 			rdata += sizeof(a) - pbyte;
677 		}
678 
679 		/* prefix name: provided only when prefix len > 0 */
680 		if (pbit == 0)
681 			break;
682 		if (rdata >= edata) goto formerr;
683 		T(addstr(" ", 1, &buf, &buflen));
684 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
685 
686 		break;
687 	    }
688 
689 	case ns_t_opt: {
690 		len = SPRINTF((tmp, "%u bytes", class));
691 		T(addstr(tmp, len, &buf, &buflen));
692 		break;
693 	    }
694 
695 	case ns_t_ds:
696 	case ns_t_dlv:
697 	case ns_t_sshfp: {
698 		u_int t;
699 
700 		if (type == ns_t_ds || type == ns_t_dlv) {
701 			if (rdlen < 4U) goto formerr;
702 			t = ns_get16(rdata);
703 			rdata += NS_INT16SZ;
704 			len = SPRINTF((tmp, "%u ", t));
705 			T(addstr(tmp, len, &buf, &buflen));
706 		} else
707 			if (rdlen < 2U) goto formerr;
708 
709 		len = SPRINTF((tmp, "%u ", *rdata));
710 		T(addstr(tmp, len, &buf, &buflen));
711 		rdata++;
712 
713 		len = SPRINTF((tmp, "%u ", *rdata));
714 		T(addstr(tmp, len, &buf, &buflen));
715 		rdata++;
716 
717 		while (rdata < edata) {
718 			len = SPRINTF((tmp, "%02X", *rdata));
719 			T(addstr(tmp, len, &buf, &buflen));
720 			rdata++;
721 		}
722 		break;
723 	    }
724 
725 	case ns_t_nsec3:
726 	case ns_t_nsec3param: {
727 		u_int t, w, l, j, k, c;
728 
729 		len = SPRINTF((tmp, "%u ", *rdata));
730 		T(addstr(tmp, len, &buf, &buflen));
731 		rdata++;
732 
733 		len = SPRINTF((tmp, "%u ", *rdata));
734 		T(addstr(tmp, len, &buf, &buflen));
735 		rdata++;
736 
737 		t = ns_get16(rdata);
738 		rdata += NS_INT16SZ;
739 		len = SPRINTF((tmp, "%u ", t));
740 		T(addstr(tmp, len, &buf, &buflen));
741 
742 		t = *rdata++;
743 		if (t == 0) {
744 			T(addstr("-", 1, &buf, &buflen));
745 		} else {
746 			while (t-- > 0) {
747 				len = SPRINTF((tmp, "%02X", *rdata));
748 				T(addstr(tmp, len, &buf, &buflen));
749 				rdata++;
750 			}
751 		}
752 		if (type == ns_t_nsec3param)
753 			break;
754 		T(addstr(" ", 1, &buf, &buflen));
755 
756 		t = *rdata++;
757 		while (t > 0) {
758 			switch (t) {
759 			case 1:
760 				tmp[0] = base32hex[((rdata[0]>>3)&0x1f)];
761 				tmp[1] = base32hex[((rdata[0]<<2)&0x1c)];
762 				tmp[2] = tmp[3] = tmp[4] = '=';
763 				tmp[5] = tmp[6] = tmp[7] = '=';
764 				break;
765 			case 2:
766 				tmp[0] = base32hex[((rdata[0]>>3)&0x1f)];
767 				tmp[1] = base32hex[((rdata[0]<<2)&0x1c)|
768 						   ((rdata[1]>>6)&0x03)];
769 				tmp[2] = base32hex[((rdata[1]>>1)&0x1f)];
770 				tmp[3] = base32hex[((rdata[1]<<4)&0x10)];
771 				tmp[4] = tmp[5] = tmp[6] = tmp[7] = '=';
772 				break;
773 			case 3:
774 				tmp[0] = base32hex[((rdata[0]>>3)&0x1f)];
775 				tmp[1] = base32hex[((rdata[0]<<2)&0x1c)|
776 						   ((rdata[1]>>6)&0x03)];
777 				tmp[2] = base32hex[((rdata[1]>>1)&0x1f)];
778 				tmp[3] = base32hex[((rdata[1]<<4)&0x10)|
779 						   ((rdata[2]>>4)&0x0f)];
780 				tmp[4] = base32hex[((rdata[2]<<1)&0x1e)];
781 				tmp[5] = tmp[6] = tmp[7] = '=';
782 				break;
783 			case 4:
784 				tmp[0] = base32hex[((rdata[0]>>3)&0x1f)];
785 				tmp[1] = base32hex[((rdata[0]<<2)&0x1c)|
786 						   ((rdata[1]>>6)&0x03)];
787 				tmp[2] = base32hex[((rdata[1]>>1)&0x1f)];
788 				tmp[3] = base32hex[((rdata[1]<<4)&0x10)|
789 						   ((rdata[2]>>4)&0x0f)];
790 				tmp[4] = base32hex[((rdata[2]<<1)&0x1e)|
791 						   ((rdata[3]>>7)&0x01)];
792 				tmp[5] = base32hex[((rdata[3]>>2)&0x1f)];
793 				tmp[6] = base32hex[(rdata[3]<<3)&0x18];
794 				tmp[7] = '=';
795 				break;
796 			default:
797 				tmp[0] = base32hex[((rdata[0]>>3)&0x1f)];
798 				tmp[1] = base32hex[((rdata[0]<<2)&0x1c)|
799 						   ((rdata[1]>>6)&0x03)];
800 				tmp[2] = base32hex[((rdata[1]>>1)&0x1f)];
801 				tmp[3] = base32hex[((rdata[1]<<4)&0x10)|
802 						   ((rdata[2]>>4)&0x0f)];
803 				tmp[4] = base32hex[((rdata[2]<<1)&0x1e)|
804 						   ((rdata[3]>>7)&0x01)];
805 				tmp[5] = base32hex[((rdata[3]>>2)&0x1f)];
806 				tmp[6] = base32hex[((rdata[3]<<3)&0x18)|
807 						   ((rdata[4]>>5)&0x07)];
808 				tmp[7] = base32hex[(rdata[4]&0x1f)];
809 				break;
810 			}
811 			T(addstr(tmp, 8, &buf, &buflen));
812 			if (t >= 5) {
813 				rdata += 5;
814 				t -= 5;
815 			} else {
816 				rdata += t;
817 				t -= t;
818 			}
819 		}
820 
821 		while (rdata < edata) {
822 			w = *rdata++;
823 			l = *rdata++;
824 			for (j = 0; j < l; j++) {
825 				if (rdata[j] == 0)
826 					continue;
827 				for (k = 0; k < 8; k++) {
828 					if ((rdata[j] & (0x80 >> k)) == 0)
829 						continue;
830 					c = w * 256 + j * 8 + k;
831 					len = SPRINTF((tmp, " %s", p_type(c)));
832 					T(addstr(tmp, len, &buf, &buflen));
833 				}
834 			}
835 			rdata += l;
836 		}
837 		break;
838 	    }
839 
840 	case ns_t_nsec: {
841 		u_int w, l, j, k, c;
842 
843 		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
844 
845 		while (rdata < edata) {
846 			w = *rdata++;
847 			l = *rdata++;
848 			for (j = 0; j < l; j++) {
849 				if (rdata[j] == 0)
850 					continue;
851 				for (k = 0; k < 8; k++) {
852 					if ((rdata[j] & (0x80 >> k)) == 0)
853 						continue;
854 					c = w * 256 + j * 8 + k;
855 					len = SPRINTF((tmp, " %s", p_type(c)));
856 					T(addstr(tmp, len, &buf, &buflen));
857 				}
858 			}
859 			rdata += l;
860 		}
861 		break;
862 	    }
863 
864 	case ns_t_dhcid: {
865 		int n;
866 		unsigned int siz;
867 		char base64_dhcid[8192];
868 		const char *leader;
869 
870 		siz = (edata-rdata)*4/3 + 4; /* "+4" accounts for trailing \0 */
871 		if (siz > sizeof(base64_dhcid) * 3/4) {
872 			const char *str = "record too long to print";
873 			T(addstr(str, strlen(str), &buf, &buflen));
874 		} else {
875 			len = b64_ntop(rdata, edata-rdata, base64_dhcid, siz);
876 
877 			if (len < 0)
878 				goto formerr;
879 
880 			else if (len > 15) {
881 				T(addstr(" (", 2, &buf, &buflen));
882 				leader = "\n\t\t";
883 				spaced = 0;
884 			}
885 			else
886 				leader = " ";
887 
888 			for (n = 0; n < len; n += 48) {
889 				T(addstr(leader, strlen(leader),
890 					 &buf, &buflen));
891 				T(addstr(base64_dhcid + n, MIN(len - n, 48),
892 					 &buf, &buflen));
893 			}
894 			if (len > 15)
895 				T(addstr(" )", 2, &buf, &buflen));
896 		}
897 	}
898 	/* FALLTHROUGH */
899 
900 	case ns_t_ipseckey: {
901 		int n;
902 		unsigned int siz;
903 		char base64_key[8192];
904 		const char *leader;
905 
906 		if (rdlen < 2)
907 			goto formerr;
908 
909 		switch (rdata[1]) {
910 		case 0:
911 		case 3:
912 			if (rdlen < 3)
913 				goto formerr;
914 			break;
915 		case 1:
916 			if (rdlen < 7)
917 				goto formerr;
918 			break;
919 		case 2:
920 			if (rdlen < 19)
921 				goto formerr;
922 			break;
923 		default:
924 			comment = "unknown IPSECKEY gateway type";
925 			goto hexify;
926 		}
927 
928 		len = SPRINTF((tmp, "%u ", *rdata));
929 		T(addstr(tmp, len, &buf, &buflen));
930 		rdata++;
931 
932 		len = SPRINTF((tmp, "%u ", *rdata));
933 		T(addstr(tmp, len, &buf, &buflen));
934 		rdata++;
935 
936 		len = SPRINTF((tmp, "%u ", *rdata));
937 		T(addstr(tmp, len, &buf, &buflen));
938 		rdata++;
939 
940 		switch (rdata[-2]) {
941 		case 0:
942 			T(addstr(".", 1, &buf, &buflen));
943 			break;
944 		case 1:
945 			(void) inet_ntop(AF_INET, rdata, buf, buflen);
946 			addlen(strlen(buf), &buf, &buflen);
947 			rdata += 4;
948 			break;
949 		case 2:
950 			(void) inet_ntop(AF_INET6, rdata, buf, buflen);
951 			addlen(strlen(buf), &buf, &buflen);
952 			rdata += 16;
953 			break;
954 		case 3:
955 			T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
956 			break;
957 		}
958 
959 		if (rdata >= edata)
960 			break;
961 
962 		siz = (edata-rdata)*4/3 + 4; /* "+4" accounts for trailing \0 */
963 		if (siz > sizeof(base64_key) * 3/4) {
964 			const char *str = "record too long to print";
965 			T(addstr(str, strlen(str), &buf, &buflen));
966 		} else {
967 			len = b64_ntop(rdata, edata-rdata, base64_key, siz);
968 
969 			if (len < 0)
970 				goto formerr;
971 
972 			else if (len > 15) {
973 				T(addstr(" (", 2, &buf, &buflen));
974 				leader = "\n\t\t";
975 				spaced = 0;
976 			}
977 			else
978 				leader = " ";
979 
980 			for (n = 0; n < len; n += 48) {
981 				T(addstr(leader, strlen(leader),
982 					 &buf, &buflen));
983 				T(addstr(base64_key + n, MIN(len - n, 48),
984 					 &buf, &buflen));
985 			}
986 			if (len > 15)
987 				T(addstr(" )", 2, &buf, &buflen));
988 		}
989 	}
990 	/* FALLTHROUGH */
991 
992 	case ns_t_hip: {
993 		unsigned int i, hip_len, algorithm, key_len;
994 		char base64_key[NS_MD5RSA_MAX_BASE64];
995 		unsigned int siz;
996 		const char *leader = "\n\t\t\t\t\t";
997 
998 		hip_len = *rdata++;
999 		algorithm = *rdata++;
1000 		key_len = ns_get16(rdata);
1001 		rdata += NS_INT16SZ;
1002 
1003 		siz = key_len*4/3 + 4; /* "+4" accounts for trailing \0 */
1004 		if (siz > sizeof(base64_key) * 3/4) {
1005 			const char *str = "record too long to print";
1006 			T(addstr(str, strlen(str), &buf, &buflen));
1007 		} else {
1008 			len = sprintf(tmp, "( %u ", algorithm);
1009 			T(addstr(tmp, len, &buf, &buflen));
1010 
1011 			for (i = 0; i < hip_len; i++) {
1012 				len = sprintf(tmp, "%02X", *rdata);
1013 				T(addstr(tmp, len, &buf, &buflen));
1014 				rdata++;
1015 			}
1016 			T(addstr(leader, strlen(leader), &buf, &buflen));
1017 
1018 			len = b64_ntop(rdata, key_len, base64_key, siz);
1019 			if (len < 0)
1020 				goto formerr;
1021 
1022 			T(addstr(base64_key, len, &buf, &buflen));
1023 
1024 			rdata += key_len;
1025 			while (rdata < edata) {
1026 				T(addstr(leader, strlen(leader), &buf, &buflen));
1027 				T(addname(msg, msglen, &rdata, origin,
1028 					  &buf, &buflen));
1029 			}
1030 			T(addstr(" )", 2, &buf, &buflen));
1031 		}
1032 		break;
1033 	}
1034 
1035 	default:
1036 		comment = "unknown RR type";
1037 		goto hexify;
1038 	}
1039 	return (buf - obuf);
1040  formerr:
1041 	comment = "RR format error";
1042  hexify: {
1043 	int n, m;
1044 	char *p;
1045 
1046 	len = SPRINTF((tmp, "\\# %u%s\t; %s", (unsigned)(edata - rdata),
1047 		       rdlen != 0U ? " (" : "", comment));
1048 	T(addstr(tmp, len, &buf, &buflen));
1049 	while (rdata < edata) {
1050 		p = tmp;
1051 		p += SPRINTF((p, "\n\t"));
1052 		spaced = 0;
1053 		n = MIN(16, edata - rdata);
1054 		for (m = 0; m < n; m++)
1055 			p += SPRINTF((p, "%02x ", rdata[m]));
1056 		T(addstr(tmp, p - tmp, &buf, &buflen));
1057 		if (n < 16) {
1058 			T(addstr(")", 1, &buf, &buflen));
1059 			T(addtab(p - tmp + 1, 48, spaced, &buf, &buflen));
1060 		}
1061 		p = tmp;
1062 		p += SPRINTF((p, "; "));
1063 		for (m = 0; m < n; m++)
1064 			*p++ = (isascii(rdata[m]) && isprint(rdata[m]))
1065 				? rdata[m]
1066 				: '.';
1067 		T(addstr(tmp, p - tmp, &buf, &buflen));
1068 		rdata += n;
1069 	}
1070 	return (buf - obuf);
1071     }
1072 }
1073 
1074 /* Private. */
1075 
1076 /*%
1077  * size_t
1078  * prune_origin(name, origin)
1079  *	Find out if the name is at or under the current origin.
1080  * return:
1081  *	Number of characters in name before start of origin,
1082  *	or length of name if origin does not match.
1083  * notes:
1084  *	This function should share code with samedomain().
1085  */
1086 static size_t
1087 prune_origin(const char *name, const char *origin) {
1088 	const char *oname = name;
1089 
1090 	while (*name != '\0') {
1091 		if (origin != NULL && ns_samename(name, origin) == 1)
1092 			return (name - oname - (name > oname));
1093 		while (*name != '\0') {
1094 			if (*name == '\\') {
1095 				name++;
1096 				/* XXX need to handle \nnn form. */
1097 				if (*name == '\0')
1098 					break;
1099 			} else if (*name == '.') {
1100 				name++;
1101 				break;
1102 			}
1103 			name++;
1104 		}
1105 	}
1106 	return (name - oname);
1107 }
1108 
1109 /*%
1110  * int
1111  * charstr(rdata, edata, buf, buflen)
1112  *	Format a <character-string> into the presentation buffer.
1113  * return:
1114  *	Number of rdata octets consumed
1115  *	0 for protocol format error
1116  *	-1 for output buffer error
1117  * side effects:
1118  *	buffer is advanced on success.
1119  */
1120 static int
1121 charstr(const u_char *rdata, const u_char *edata, char **buf, size_t *buflen) {
1122 	const u_char *odata = rdata;
1123 	size_t save_buflen = *buflen;
1124 	char *save_buf = *buf;
1125 
1126 	if (addstr("\"", 1, buf, buflen) < 0)
1127 		goto enospc;
1128 	if (rdata < edata) {
1129 		int n = *rdata;
1130 
1131 		if (rdata + 1 + n <= edata) {
1132 			rdata++;
1133 			while (n-- > 0) {
1134 				if (strchr("\n\"\\", *rdata) != NULL)
1135 					if (addstr("\\", 1, buf, buflen) < 0)
1136 						goto enospc;
1137 				if (addstr((const char *)rdata, 1,
1138 					   buf, buflen) < 0)
1139 					goto enospc;
1140 				rdata++;
1141 			}
1142 		}
1143 	}
1144 	if (addstr("\"", 1, buf, buflen) < 0)
1145 		goto enospc;
1146 	return (rdata - odata);
1147  enospc:
1148 	errno = ENOSPC;
1149 	*buf = save_buf;
1150 	*buflen = save_buflen;
1151 	return (-1);
1152 }
1153 
1154 static int
1155 addname(const u_char *msg, size_t msglen,
1156 	const u_char **pp, const char *origin,
1157 	char **buf, size_t *buflen)
1158 {
1159 	size_t newlen, save_buflen = *buflen;
1160 	char *save_buf = *buf;
1161 	int n;
1162 
1163 	n = dn_expand(msg, msg + msglen, *pp, *buf, *buflen);
1164 	if (n < 0)
1165 		goto enospc;	/*%< Guess. */
1166 	newlen = prune_origin(*buf, origin);
1167 	if (**buf == '\0') {
1168 		goto root;
1169 	} else if (newlen == 0U) {
1170 		/* Use "@" instead of name. */
1171 		if (newlen + 2 > *buflen)
1172 			goto enospc;        /* No room for "@\0". */
1173 		(*buf)[newlen++] = '@';
1174 		(*buf)[newlen] = '\0';
1175 	} else {
1176 		if (((origin == NULL || origin[0] == '\0') ||
1177 		    (origin[0] != '.' && origin[1] != '\0' &&
1178 		    (*buf)[newlen] == '\0')) && (*buf)[newlen - 1] != '.') {
1179 			/* No trailing dot. */
1180  root:
1181 			if (newlen + 2 > *buflen)
1182 				goto enospc;	/* No room for ".\0". */
1183 			(*buf)[newlen++] = '.';
1184 			(*buf)[newlen] = '\0';
1185 		}
1186 	}
1187 	*pp += n;
1188 	addlen(newlen, buf, buflen);
1189 	**buf = '\0';
1190 	return (newlen);
1191  enospc:
1192 	errno = ENOSPC;
1193 	*buf = save_buf;
1194 	*buflen = save_buflen;
1195 	return (-1);
1196 }
1197 
1198 static void
1199 addlen(size_t len, char **buf, size_t *buflen) {
1200 	INSIST(len <= *buflen);
1201 	*buf += len;
1202 	*buflen -= len;
1203 }
1204 
1205 static int
1206 addstr(const char *src, size_t len, char **buf, size_t *buflen) {
1207 	if (len >= *buflen) {
1208 		errno = ENOSPC;
1209 		return (-1);
1210 	}
1211 	memcpy(*buf, src, len);
1212 	addlen(len, buf, buflen);
1213 	**buf = '\0';
1214 	return (0);
1215 }
1216 
1217 static int
1218 addtab(size_t len, size_t target, int spaced, char **buf, size_t *buflen) {
1219 	size_t save_buflen = *buflen;
1220 	char *save_buf = *buf;
1221 	int t;
1222 
1223 	if (spaced || len >= target - 1) {
1224 		T(addstr("  ", 2, buf, buflen));
1225 		spaced = 1;
1226 	} else {
1227 		for (t = (target - len - 1) / 8; t >= 0; t--)
1228 			if (addstr("\t", 1, buf, buflen) < 0) {
1229 				*buflen = save_buflen;
1230 				*buf = save_buf;
1231 				return (-1);
1232 			}
1233 		spaced = 0;
1234 	}
1235 	return (spaced);
1236 }
1237 
1238 /*! \file */
1239