xref: /netbsd-src/external/mpl/bind/dist/lib/dns/rcode.c (revision e6c7e151de239c49d2e38720a061ed9d1fa99309)
1 /*	$NetBSD: rcode.c,v 1.6 2019/11/27 05:48:41 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * This Source Code Form is subject to the terms of the Mozilla Public
7  * License, v. 2.0. If a copy of the MPL was not distributed with this
8  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
9  *
10  * See the COPYRIGHT file distributed with this work for additional
11  * information regarding copyright ownership.
12  */
13 
14 
15 #include <config.h>
16 
17 #include <ctype.h>
18 #include <inttypes.h>
19 #include <stdbool.h>
20 #include <stdlib.h>
21 
22 #include <isc/buffer.h>
23 #include <isc/parseint.h>
24 #include <isc/print.h>
25 #include <isc/region.h>
26 #include <isc/result.h>
27 #include <isc/stdio.h>
28 #include <isc/string.h>
29 #include <isc/types.h>
30 #include <isc/util.h>
31 
32 #include <pk11/site.h>
33 
34 #include <dns/cert.h>
35 #include <dns/ds.h>
36 #include <dns/dsdigest.h>
37 #include <dns/keyflags.h>
38 #include <dns/keyvalues.h>
39 #include <dns/rcode.h>
40 #include <dns/rdataclass.h>
41 #include <dns/result.h>
42 #include <dns/secalg.h>
43 #include <dns/secproto.h>
44 
45 #define RETERR(x) \
46 	do { \
47 		isc_result_t _r = (x); \
48 		if (_r != ISC_R_SUCCESS) \
49 			return (_r); \
50 	} while (/*CONSTCOND*/0)
51 
52 #define NUMBERSIZE sizeof("037777777777") /* 2^32-1 octal + NUL */
53 
54 #define TOTEXTONLY 0x01
55 
56 #define RCODENAMES \
57 	/* standard rcodes */ \
58 	{ dns_rcode_noerror, "NOERROR", 0}, \
59 	{ dns_rcode_formerr, "FORMERR", 0}, \
60 	{ dns_rcode_servfail, "SERVFAIL", 0}, \
61 	{ dns_rcode_nxdomain, "NXDOMAIN", 0}, \
62 	{ dns_rcode_notimp, "NOTIMP", 0}, \
63 	{ dns_rcode_refused, "REFUSED", 0}, \
64 	{ dns_rcode_yxdomain, "YXDOMAIN", 0}, \
65 	{ dns_rcode_yxrrset, "YXRRSET", 0}, \
66 	{ dns_rcode_nxrrset, "NXRRSET", 0}, \
67 	{ dns_rcode_notauth, "NOTAUTH", 0}, \
68 	{ dns_rcode_notzone, "NOTZONE", 0}, \
69 	{ 11, "RESERVED11", TOTEXTONLY}, \
70 	{ 12, "RESERVED12", TOTEXTONLY}, \
71 	{ 13, "RESERVED13", TOTEXTONLY}, \
72 	{ 14, "RESERVED14", TOTEXTONLY}, \
73 	{ 15, "RESERVED15", TOTEXTONLY},
74 
75 #define ERCODENAMES \
76 	/* extended rcodes */ \
77 	{ dns_rcode_badvers, "BADVERS", 0}, \
78 	{ dns_rcode_badcookie, "BADCOOKIE", 0}, \
79 	{ 0, NULL, 0 }
80 
81 #define TSIGRCODENAMES \
82 	/* extended rcodes */ \
83 	{ dns_tsigerror_badsig, "BADSIG", 0}, \
84 	{ dns_tsigerror_badkey, "BADKEY", 0}, \
85 	{ dns_tsigerror_badtime, "BADTIME", 0}, \
86 	{ dns_tsigerror_badmode, "BADMODE", 0}, \
87 	{ dns_tsigerror_badname, "BADNAME", 0}, \
88 	{ dns_tsigerror_badalg, "BADALG", 0}, \
89 	{ dns_tsigerror_badtrunc, "BADTRUNC", 0}, \
90 	{ 0, NULL, 0 }
91 
92 /* RFC4398 section 2.1 */
93 
94 #define CERTNAMES \
95 	{ 1, "PKIX", 0}, \
96 	{ 2, "SPKI", 0}, \
97 	{ 3, "PGP", 0}, \
98 	{ 4, "IPKIX", 0}, \
99 	{ 5, "ISPKI", 0}, \
100 	{ 6, "IPGP", 0}, \
101 	{ 7, "ACPKIX", 0}, \
102 	{ 8, "IACPKIX", 0}, \
103 	{ 253, "URI", 0}, \
104 	{ 254, "OID", 0}, \
105 	{ 0, NULL, 0}
106 
107 /* RFC2535 section 7, RFC3110 */
108 
109 #define SECALGNAMES \
110 	{ DNS_KEYALG_RSAMD5, "RSAMD5", 0 }, \
111 	{ DNS_KEYALG_DH, "DH", 0 }, \
112 	{ DNS_KEYALG_DSA, "DSA", 0 }, \
113 	{ DNS_KEYALG_RSASHA1, "RSASHA1", 0 }, \
114 	{ DNS_KEYALG_NSEC3DSA, "NSEC3DSA", 0 }, \
115 	{ DNS_KEYALG_NSEC3RSASHA1, "NSEC3RSASHA1", 0 }, \
116 	{ DNS_KEYALG_RSASHA256, "RSASHA256", 0 }, \
117 	{ DNS_KEYALG_RSASHA512, "RSASHA512", 0 }, \
118 	{ DNS_KEYALG_ECCGOST, "ECCGOST", 0 }, \
119 	{ DNS_KEYALG_ECDSA256, "ECDSAP256SHA256", 0 }, \
120 	{ DNS_KEYALG_ECDSA256, "ECDSA256", 0 }, \
121 	{ DNS_KEYALG_ECDSA384, "ECDSAP384SHA384", 0 }, \
122 	{ DNS_KEYALG_ECDSA384, "ECDSA384", 0 }, \
123 	{ DNS_KEYALG_ED25519, "ED25519", 0 }, \
124 	{ DNS_KEYALG_ED448, "ED448", 0 }, \
125 	{ DNS_KEYALG_INDIRECT, "INDIRECT", 0 }, \
126 	{ DNS_KEYALG_PRIVATEDNS, "PRIVATEDNS", 0 }, \
127 	{ DNS_KEYALG_PRIVATEOID, "PRIVATEOID", 0 }, \
128 	{ 0, NULL, 0}
129 
130 /* RFC2535 section 7.1 */
131 
132 #define SECPROTONAMES \
133 	{   0,    "NONE", 0 }, \
134 	{   1,    "TLS", 0 }, \
135 	{   2,    "EMAIL", 0 }, \
136 	{   3,    "DNSSEC", 0 }, \
137 	{   4,    "IPSEC", 0 }, \
138 	{ 255,    "ALL", 0 }, \
139 	{ 0, NULL, 0}
140 
141 #define HASHALGNAMES \
142 	{ 1, "SHA-1", 0 }, \
143 	{ 0, NULL, 0 }
144 
145 /* RFC3658, RFC4509, RFC5933, RFC6605 */
146 
147 #define DSDIGESTNAMES \
148 	{ DNS_DSDIGEST_SHA1, "SHA-1", 0 }, \
149 	{ DNS_DSDIGEST_SHA256, "SHA-256", 0 }, \
150 	{ DNS_DSDIGEST_GOST, "GOST", 0 }, \
151 	{ DNS_DSDIGEST_SHA384, "SHA-384", 0 }, \
152 	{ 0, NULL, 0}
153 
154 struct tbl {
155 	unsigned int    value;
156 	const char      *name;
157 	int             flags;
158 };
159 
160 static struct tbl rcodes[] = { RCODENAMES ERCODENAMES };
161 static struct tbl tsigrcodes[] = { RCODENAMES TSIGRCODENAMES };
162 static struct tbl certs[] = { CERTNAMES };
163 static struct tbl secalgs[] = { SECALGNAMES };
164 static struct tbl secprotos[] = { SECPROTONAMES };
165 static struct tbl hashalgs[] = { HASHALGNAMES };
166 static struct tbl dsdigests[] = { DSDIGESTNAMES };
167 
168 static struct keyflag {
169 	const char *name;
170 	unsigned int value;
171 	unsigned int mask;
172 } keyflags[] = {
173 	{ "NOCONF", 0x4000, 0xC000 },
174 	{ "NOAUTH", 0x8000, 0xC000 },
175 	{ "NOKEY",  0xC000, 0xC000 },
176 	{ "FLAG2",  0x2000, 0x2000 },
177 	{ "EXTEND", 0x1000, 0x1000 },
178 	{ "FLAG4",  0x0800, 0x0800 },
179 	{ "FLAG5",  0x0400, 0x0400 },
180 	{ "USER",   0x0000, 0x0300 },
181 	{ "ZONE",   0x0100, 0x0300 },
182 	{ "HOST",   0x0200, 0x0300 },
183 	{ "NTYP3",  0x0300, 0x0300 },
184 	{ "FLAG8",  0x0080, 0x0080 },
185 	{ "FLAG9",  0x0040, 0x0040 },
186 	{ "FLAG10", 0x0020, 0x0020 },
187 	{ "FLAG11", 0x0010, 0x0010 },
188 	{ "SIG0",   0x0000, 0x000F },
189 	{ "SIG1",   0x0001, 0x000F },
190 	{ "SIG2",   0x0002, 0x000F },
191 	{ "SIG3",   0x0003, 0x000F },
192 	{ "SIG4",   0x0004, 0x000F },
193 	{ "SIG5",   0x0005, 0x000F },
194 	{ "SIG6",   0x0006, 0x000F },
195 	{ "SIG7",   0x0007, 0x000F },
196 	{ "SIG8",   0x0008, 0x000F },
197 	{ "SIG9",   0x0009, 0x000F },
198 	{ "SIG10",  0x000A, 0x000F },
199 	{ "SIG11",  0x000B, 0x000F },
200 	{ "SIG12",  0x000C, 0x000F },
201 	{ "SIG13",  0x000D, 0x000F },
202 	{ "SIG14",  0x000E, 0x000F },
203 	{ "SIG15",  0x000F, 0x000F },
204 	{ "KSK",  DNS_KEYFLAG_KSK, DNS_KEYFLAG_KSK },
205 	{ NULL,     0, 0 }
206 };
207 
208 static isc_result_t
209 str_totext(const char *source, isc_buffer_t *target) {
210 	unsigned int l;
211 	isc_region_t region;
212 
213 	isc_buffer_availableregion(target, &region);
214 	l = strlen(source);
215 
216 	if (l > region.length)
217 		return (ISC_R_NOSPACE);
218 
219 	memmove(region.base, source, l);
220 	isc_buffer_add(target, l);
221 	return (ISC_R_SUCCESS);
222 }
223 
224 static isc_result_t
225 maybe_numeric(unsigned int *valuep, isc_textregion_t *source,
226 	      unsigned int max, bool hex_allowed)
227 {
228 	isc_result_t result;
229 	uint32_t n;
230 	char buffer[NUMBERSIZE];
231 	int v;
232 
233 	if (! isdigit(source->base[0] & 0xff) ||
234 	    source->length > NUMBERSIZE - 1)
235 	{
236 		return (ISC_R_BADNUMBER);
237 	}
238 
239 	/*
240 	 * We have a potential number.	Try to parse it with
241 	 * isc_parse_uint32().	isc_parse_uint32() requires
242 	 * null termination, so we must make a copy.
243 	 */
244 	v = snprintf(buffer, sizeof(buffer), "%.*s",
245 		     (int)source->length, source->base);
246 	if (v < 0 || (unsigned)v != source->length) {
247 		return (ISC_R_BADNUMBER);
248 	}
249 	INSIST(buffer[source->length] == '\0');
250 
251 	result = isc_parse_uint32(&n, buffer, 10);
252 	if (result == ISC_R_BADNUMBER && hex_allowed) {
253 		result = isc_parse_uint32(&n, buffer, 16);
254 	}
255 	if (result != ISC_R_SUCCESS) {
256 		return (result);
257 	}
258 	if (n > max) {
259 		return (ISC_R_RANGE);
260 	}
261 	*valuep = n;
262 	return (ISC_R_SUCCESS);
263 }
264 
265 static isc_result_t
266 dns_mnemonic_fromtext(unsigned int *valuep, isc_textregion_t *source,
267 		      struct tbl *table, unsigned int max)
268 {
269 	isc_result_t result;
270 	int i;
271 
272 	result = maybe_numeric(valuep, source, max, false);
273 	if (result != ISC_R_BADNUMBER)
274 		return (result);
275 
276 	for (i = 0; table[i].name != NULL; i++) {
277 		unsigned int n;
278 		n = strlen(table[i].name);
279 		if (n == source->length &&
280 		    (table[i].flags & TOTEXTONLY) == 0 &&
281 		    strncasecmp(source->base, table[i].name, n) == 0) {
282 			*valuep = table[i].value;
283 			return (ISC_R_SUCCESS);
284 		}
285 	}
286 	return (DNS_R_UNKNOWN);
287 }
288 
289 static isc_result_t
290 dns_mnemonic_totext(unsigned int value, isc_buffer_t *target,
291 		    struct tbl *table)
292 {
293 	int i = 0;
294 	char buf[sizeof("4294967296")];
295 	while (table[i].name != NULL) {
296 		if (table[i].value == value) {
297 			return (str_totext(table[i].name, target));
298 		}
299 		i++;
300 	}
301 	snprintf(buf, sizeof(buf), "%u", value);
302 	return (str_totext(buf, target));
303 }
304 
305 isc_result_t
306 dns_rcode_fromtext(dns_rcode_t *rcodep, isc_textregion_t *source) {
307 	unsigned int value;
308 	RETERR(dns_mnemonic_fromtext(&value, source, rcodes, 0xffff));
309 	*rcodep = value;
310 	return (ISC_R_SUCCESS);
311 }
312 
313 isc_result_t
314 dns_rcode_totext(dns_rcode_t rcode, isc_buffer_t *target) {
315 	return (dns_mnemonic_totext(rcode, target, rcodes));
316 }
317 
318 isc_result_t
319 dns_tsigrcode_fromtext(dns_rcode_t *rcodep, isc_textregion_t *source) {
320 	unsigned int value;
321 	RETERR(dns_mnemonic_fromtext(&value, source, tsigrcodes, 0xffff));
322 	*rcodep = value;
323 	return (ISC_R_SUCCESS);
324 }
325 
326 isc_result_t
327 dns_tsigrcode_totext(dns_rcode_t rcode, isc_buffer_t *target) {
328 	return (dns_mnemonic_totext(rcode, target, tsigrcodes));
329 }
330 
331 isc_result_t
332 dns_cert_fromtext(dns_cert_t *certp, isc_textregion_t *source) {
333 	unsigned int value;
334 	RETERR(dns_mnemonic_fromtext(&value, source, certs, 0xffff));
335 	*certp = value;
336 	return (ISC_R_SUCCESS);
337 }
338 
339 isc_result_t
340 dns_cert_totext(dns_cert_t cert, isc_buffer_t *target) {
341 	return (dns_mnemonic_totext(cert, target, certs));
342 }
343 
344 isc_result_t
345 dns_secalg_fromtext(dns_secalg_t *secalgp, isc_textregion_t *source) {
346 	unsigned int value;
347 	RETERR(dns_mnemonic_fromtext(&value, source, secalgs, 0xff));
348 	*secalgp = value;
349 	return (ISC_R_SUCCESS);
350 }
351 
352 isc_result_t
353 dns_secalg_totext(dns_secalg_t secalg, isc_buffer_t *target) {
354 	return (dns_mnemonic_totext(secalg, target, secalgs));
355 }
356 
357 void
358 dns_secalg_format(dns_secalg_t alg, char *cp, unsigned int size) {
359 	isc_buffer_t b;
360 	isc_region_t r;
361 	isc_result_t result;
362 
363 	REQUIRE(cp != NULL && size > 0);
364 	isc_buffer_init(&b, cp, size - 1);
365 	result = dns_secalg_totext(alg, &b);
366 	isc_buffer_usedregion(&b, &r);
367 	r.base[r.length] = 0;
368 	if (result != ISC_R_SUCCESS) {
369 		r.base[0] = 0;
370 	}
371 }
372 
373 isc_result_t
374 dns_secproto_fromtext(dns_secproto_t *secprotop, isc_textregion_t *source) {
375 	unsigned int value;
376 	RETERR(dns_mnemonic_fromtext(&value, source, secprotos, 0xff));
377 	*secprotop = value;
378 	return (ISC_R_SUCCESS);
379 }
380 
381 isc_result_t
382 dns_secproto_totext(dns_secproto_t secproto, isc_buffer_t *target) {
383 	return (dns_mnemonic_totext(secproto, target, secprotos));
384 }
385 
386 isc_result_t
387 dns_hashalg_fromtext(unsigned char *hashalg, isc_textregion_t *source) {
388 	unsigned int value;
389 	RETERR(dns_mnemonic_fromtext(&value, source, hashalgs, 0xff));
390 	*hashalg = value;
391 	return (ISC_R_SUCCESS);
392 }
393 
394 isc_result_t
395 dns_keyflags_fromtext(dns_keyflags_t *flagsp, isc_textregion_t *source)
396 {
397 	isc_result_t result;
398 	char *text, *end;
399 	unsigned int value = 0;
400 #ifdef notyet
401 	unsigned int mask = 0;
402 #endif
403 
404 	result = maybe_numeric(&value, source, 0xffff, true);
405 	if (result == ISC_R_SUCCESS) {
406 		*flagsp = value;
407 		return (ISC_R_SUCCESS);
408 	}
409 	if (result != ISC_R_BADNUMBER)
410 		return (result);
411 
412 	text = source->base;
413 	end = source->base + source->length;
414 
415 	while (text < end) {
416 		struct keyflag *p;
417 		unsigned int len;
418 		char *delim = memchr(text, '|', end - text);
419 		if (delim != NULL)
420 			len = (unsigned int)(delim - text);
421 		else
422 			len = (unsigned int)(end - text);
423 		for (p = keyflags; p->name != NULL; p++) {
424 			if (strncasecmp(p->name, text, len) == 0)
425 				break;
426 		}
427 		if (p->name == NULL)
428 			return (DNS_R_UNKNOWNFLAG);
429 		value |= p->value;
430 #ifdef notyet
431 		if ((mask & p->mask) != 0)
432 			warn("overlapping key flags");
433 		mask |= p->mask;
434 #endif
435 		text += len;
436 		if (delim != NULL)
437 			text++; /* Skip "|" */
438 	}
439 	*flagsp = value;
440 	return (ISC_R_SUCCESS);
441 }
442 
443 isc_result_t
444 dns_dsdigest_fromtext(dns_dsdigest_t *dsdigestp, isc_textregion_t *source) {
445 	unsigned int value;
446 	RETERR(dns_mnemonic_fromtext(&value, source, dsdigests, 0xff));
447 	*dsdigestp = value;
448 	return (ISC_R_SUCCESS);
449 }
450 
451 isc_result_t
452 dns_dsdigest_totext(dns_dsdigest_t dsdigest, isc_buffer_t *target) {
453 	return (dns_mnemonic_totext(dsdigest, target, dsdigests));
454 }
455 
456 void
457 dns_dsdigest_format(dns_dsdigest_t typ, char *cp, unsigned int size) {
458 	isc_buffer_t b;
459 	isc_region_t r;
460 	isc_result_t result;
461 
462 	REQUIRE(cp != NULL && size > 0);
463 	isc_buffer_init(&b, cp, size - 1);
464 	result = dns_dsdigest_totext(typ, &b);
465 	isc_buffer_usedregion(&b, &r);
466 	r.base[r.length] = 0;
467 	if (result != ISC_R_SUCCESS) {
468 		r.base[0] = 0;
469 	}
470 }
471 
472 /*
473  * This uses lots of hard coded values, but how often do we actually
474  * add classes?
475  */
476 isc_result_t
477 dns_rdataclass_fromtext(dns_rdataclass_t *classp, isc_textregion_t *source) {
478 #define COMPARE(string, rdclass) \
479 	if (((sizeof(string) - 1) == source->length) \
480 	    && (strncasecmp(source->base, string, source->length) == 0)) { \
481 		*classp = rdclass; \
482 		return (ISC_R_SUCCESS); \
483 	}
484 
485 	switch (tolower((unsigned char)source->base[0])) {
486 	case 'a':
487 		COMPARE("any", dns_rdataclass_any);
488 		break;
489 	case 'c':
490 		/*
491 		 * RFC1035 says the mnemonic for the CHAOS class is CH,
492 		 * but historical BIND practice is to call it CHAOS.
493 		 * We will accept both forms, but only generate CH.
494 		 */
495 		COMPARE("ch", dns_rdataclass_chaos);
496 		COMPARE("chaos", dns_rdataclass_chaos);
497 
498 		if (source->length > 5 &&
499 		    source->length < (5 + sizeof("65000")) &&
500 		    strncasecmp("class", source->base, 5) == 0) {
501 			char buf[sizeof("65000")];
502 			char *endp;
503 			unsigned int val;
504 
505 			/*
506 			 * source->base is not required to be NUL terminated.
507 			 * Copy up to remaining bytes and NUL terminate.
508 			 */
509 			snprintf(buf, sizeof(buf), "%.*s",
510 				 (int)(source->length - 5), source->base + 5);
511 			val = strtoul(buf, &endp, 10);
512 			if (*endp == '\0' && val <= 0xffff) {
513 				*classp = (dns_rdataclass_t)val;
514 				return (ISC_R_SUCCESS);
515 			}
516 		}
517 		break;
518 	case 'h':
519 		COMPARE("hs", dns_rdataclass_hs);
520 		COMPARE("hesiod", dns_rdataclass_hs);
521 		break;
522 	case 'i':
523 		COMPARE("in", dns_rdataclass_in);
524 		break;
525 	case 'n':
526 		COMPARE("none", dns_rdataclass_none);
527 		break;
528 	case 'r':
529 		COMPARE("reserved0", dns_rdataclass_reserved0);
530 		break;
531 	}
532 
533 #undef COMPARE
534 
535 	return (DNS_R_UNKNOWN);
536 }
537 
538 isc_result_t
539 dns_rdataclass_totext(dns_rdataclass_t rdclass, isc_buffer_t *target) {
540 	switch (rdclass) {
541 	case dns_rdataclass_any:
542 		return (str_totext("ANY", target));
543 	case dns_rdataclass_chaos:
544 		return (str_totext("CH", target));
545 	case dns_rdataclass_hs:
546 		return (str_totext("HS", target));
547 	case dns_rdataclass_in:
548 		return (str_totext("IN", target));
549 	case dns_rdataclass_none:
550 		return (str_totext("NONE", target));
551 	case dns_rdataclass_reserved0:
552 		return (str_totext("RESERVED0", target));
553 	default:
554 		return (dns_rdataclass_tounknowntext(rdclass, target));
555 	}
556 }
557 
558 isc_result_t
559 dns_rdataclass_tounknowntext(dns_rdataclass_t rdclass, isc_buffer_t *target) {
560 	char buf[sizeof("CLASS65535")];
561 
562 	snprintf(buf, sizeof(buf), "CLASS%u", rdclass);
563 	return (str_totext(buf, target));
564 }
565 
566 void
567 dns_rdataclass_format(dns_rdataclass_t rdclass,
568 		      char *array, unsigned int size)
569 {
570 	isc_result_t result;
571 	isc_buffer_t buf;
572 
573 	if (size == 0U)
574 		return;
575 
576 	isc_buffer_init(&buf, array, size);
577 	result = dns_rdataclass_totext(rdclass, &buf);
578 	/*
579 	 * Null terminate.
580 	 */
581 	if (result == ISC_R_SUCCESS) {
582 		if (isc_buffer_availablelength(&buf) >= 1)
583 			isc_buffer_putuint8(&buf, 0);
584 		else
585 			result = ISC_R_NOSPACE;
586 	}
587 	if (result != ISC_R_SUCCESS)
588 		strlcpy(array, "<unknown>", size);
589 }
590