xref: /netbsd-src/external/mpl/bind/dist/lib/dns/rdatalist.c (revision cef8759bd76c1b621f8eab8faa6f208faabc2e15)
1 /*	$NetBSD: rdatalist.c,v 1.4 2020/05/24 19:46:23 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 /*! \file */
15 
16 #include <stddef.h>
17 #include <string.h>
18 
19 #include <isc/util.h>
20 
21 #include <dns/name.h>
22 #include <dns/nsec3.h>
23 #include <dns/rdata.h>
24 #include <dns/rdatalist.h>
25 #include <dns/rdataset.h>
26 
27 #include "rdatalist_p.h"
28 
29 static dns_rdatasetmethods_t methods = {
30 	isc__rdatalist_disassociate,
31 	isc__rdatalist_first,
32 	isc__rdatalist_next,
33 	isc__rdatalist_current,
34 	isc__rdatalist_clone,
35 	isc__rdatalist_count,
36 	isc__rdatalist_addnoqname,
37 	isc__rdatalist_getnoqname,
38 	isc__rdatalist_addclosest,
39 	isc__rdatalist_getclosest,
40 	NULL, /* settrust */
41 	NULL, /* expire */
42 	NULL, /* clearprefetch */
43 	isc__rdatalist_setownercase,
44 	isc__rdatalist_getownercase,
45 	NULL /* addglue */
46 };
47 
48 void
49 dns_rdatalist_init(dns_rdatalist_t *rdatalist) {
50 	REQUIRE(rdatalist != NULL);
51 
52 	/*
53 	 * Initialize rdatalist.
54 	 */
55 
56 	rdatalist->rdclass = 0;
57 	rdatalist->type = 0;
58 	rdatalist->covers = 0;
59 	rdatalist->ttl = 0;
60 	ISC_LIST_INIT(rdatalist->rdata);
61 	ISC_LINK_INIT(rdatalist, link);
62 	memset(rdatalist->upper, 0xeb, sizeof(rdatalist->upper));
63 	/*
64 	 * Clear upper set bit.
65 	 */
66 	rdatalist->upper[0] &= ~0x01;
67 }
68 
69 isc_result_t
70 dns_rdatalist_tordataset(dns_rdatalist_t *rdatalist, dns_rdataset_t *rdataset) {
71 	/*
72 	 * Make 'rdataset' refer to the rdata in 'rdatalist'.
73 	 */
74 
75 	REQUIRE(rdatalist != NULL);
76 	REQUIRE(DNS_RDATASET_VALID(rdataset));
77 	REQUIRE(!dns_rdataset_isassociated(rdataset));
78 
79 	/* Check if dns_rdatalist_init has was called. */
80 	REQUIRE(rdatalist->upper[0] == 0xea);
81 
82 	rdataset->methods = &methods;
83 	rdataset->rdclass = rdatalist->rdclass;
84 	rdataset->type = rdatalist->type;
85 	rdataset->covers = rdatalist->covers;
86 	rdataset->ttl = rdatalist->ttl;
87 	rdataset->trust = 0;
88 	rdataset->private1 = rdatalist;
89 	rdataset->private2 = NULL;
90 	rdataset->private3 = NULL;
91 	rdataset->privateuint4 = 0;
92 	rdataset->private5 = NULL;
93 
94 	return (ISC_R_SUCCESS);
95 }
96 
97 isc_result_t
98 dns_rdatalist_fromrdataset(dns_rdataset_t *rdataset,
99 			   dns_rdatalist_t **rdatalist) {
100 	REQUIRE(rdatalist != NULL && rdataset != NULL);
101 	*rdatalist = rdataset->private1;
102 
103 	return (ISC_R_SUCCESS);
104 }
105 
106 void
107 isc__rdatalist_disassociate(dns_rdataset_t *rdataset) {
108 	UNUSED(rdataset);
109 }
110 
111 isc_result_t
112 isc__rdatalist_first(dns_rdataset_t *rdataset) {
113 	dns_rdatalist_t *rdatalist;
114 
115 	rdatalist = rdataset->private1;
116 	rdataset->private2 = ISC_LIST_HEAD(rdatalist->rdata);
117 
118 	if (rdataset->private2 == NULL) {
119 		return (ISC_R_NOMORE);
120 	}
121 
122 	return (ISC_R_SUCCESS);
123 }
124 
125 isc_result_t
126 isc__rdatalist_next(dns_rdataset_t *rdataset) {
127 	dns_rdata_t *rdata;
128 
129 	REQUIRE(rdataset != NULL);
130 
131 	rdata = rdataset->private2;
132 	if (rdata == NULL) {
133 		return (ISC_R_NOMORE);
134 	}
135 
136 	rdataset->private2 = ISC_LIST_NEXT(rdata, link);
137 
138 	if (rdataset->private2 == NULL) {
139 		return (ISC_R_NOMORE);
140 	}
141 
142 	return (ISC_R_SUCCESS);
143 }
144 
145 void
146 isc__rdatalist_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) {
147 	dns_rdata_t *list_rdata;
148 
149 	REQUIRE(rdataset != NULL);
150 
151 	list_rdata = rdataset->private2;
152 	INSIST(list_rdata != NULL);
153 
154 	dns_rdata_clone(list_rdata, rdata);
155 }
156 
157 void
158 isc__rdatalist_clone(dns_rdataset_t *source, dns_rdataset_t *target) {
159 	REQUIRE(source != NULL);
160 	REQUIRE(target != NULL);
161 
162 	*target = *source;
163 
164 	/*
165 	 * Reset iterator state.
166 	 */
167 	target->private2 = NULL;
168 }
169 
170 unsigned int
171 isc__rdatalist_count(dns_rdataset_t *rdataset) {
172 	dns_rdatalist_t *rdatalist;
173 	dns_rdata_t *rdata;
174 	unsigned int count;
175 
176 	REQUIRE(rdataset != NULL);
177 
178 	rdatalist = rdataset->private1;
179 
180 	count = 0;
181 	for (rdata = ISC_LIST_HEAD(rdatalist->rdata); rdata != NULL;
182 	     rdata = ISC_LIST_NEXT(rdata, link))
183 	{
184 		count++;
185 	}
186 
187 	return (count);
188 }
189 
190 isc_result_t
191 isc__rdatalist_addnoqname(dns_rdataset_t *rdataset, const dns_name_t *name) {
192 	dns_rdataset_t *neg = NULL;
193 	dns_rdataset_t *negsig = NULL;
194 	dns_rdataset_t *rdset;
195 	dns_ttl_t ttl;
196 
197 	REQUIRE(rdataset != NULL);
198 
199 	for (rdset = ISC_LIST_HEAD(name->list); rdset != NULL;
200 	     rdset = ISC_LIST_NEXT(rdset, link))
201 	{
202 		if (rdset->rdclass != rdataset->rdclass) {
203 			continue;
204 		}
205 		if (rdset->type == dns_rdatatype_nsec ||
206 		    rdset->type == dns_rdatatype_nsec3) {
207 			neg = rdset;
208 		}
209 	}
210 	if (neg == NULL) {
211 		return (ISC_R_NOTFOUND);
212 	}
213 
214 	for (rdset = ISC_LIST_HEAD(name->list); rdset != NULL;
215 	     rdset = ISC_LIST_NEXT(rdset, link))
216 	{
217 		if (rdset->type == dns_rdatatype_rrsig &&
218 		    rdset->covers == neg->type) {
219 			negsig = rdset;
220 		}
221 	}
222 
223 	if (negsig == NULL) {
224 		return (ISC_R_NOTFOUND);
225 	}
226 	/*
227 	 * Minimise ttl.
228 	 */
229 	ttl = rdataset->ttl;
230 	if (neg->ttl < ttl) {
231 		ttl = neg->ttl;
232 	}
233 	if (negsig->ttl < ttl) {
234 		ttl = negsig->ttl;
235 	}
236 	rdataset->ttl = neg->ttl = negsig->ttl = ttl;
237 	rdataset->attributes |= DNS_RDATASETATTR_NOQNAME;
238 	rdataset->private6 = name;
239 	return (ISC_R_SUCCESS);
240 }
241 
242 isc_result_t
243 isc__rdatalist_getnoqname(dns_rdataset_t *rdataset, dns_name_t *name,
244 			  dns_rdataset_t *neg, dns_rdataset_t *negsig) {
245 	dns_rdataclass_t rdclass;
246 	dns_rdataset_t *tneg = NULL;
247 	dns_rdataset_t *tnegsig = NULL;
248 	const dns_name_t *noqname;
249 
250 	REQUIRE(rdataset != NULL);
251 	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_NOQNAME) != 0);
252 
253 	rdclass = rdataset->rdclass;
254 	noqname = rdataset->private6;
255 
256 	(void)dns_name_dynamic(noqname); /* Sanity Check. */
257 
258 	for (rdataset = ISC_LIST_HEAD(noqname->list); rdataset != NULL;
259 	     rdataset = ISC_LIST_NEXT(rdataset, link))
260 	{
261 		if (rdataset->rdclass != rdclass) {
262 			continue;
263 		}
264 		if (rdataset->type == dns_rdatatype_nsec ||
265 		    rdataset->type == dns_rdatatype_nsec3)
266 		{
267 			tneg = rdataset;
268 		}
269 	}
270 	if (tneg == NULL) {
271 		return (ISC_R_NOTFOUND);
272 	}
273 
274 	for (rdataset = ISC_LIST_HEAD(noqname->list); rdataset != NULL;
275 	     rdataset = ISC_LIST_NEXT(rdataset, link))
276 	{
277 		if (rdataset->type == dns_rdatatype_rrsig &&
278 		    rdataset->covers == tneg->type) {
279 			tnegsig = rdataset;
280 		}
281 	}
282 	if (tnegsig == NULL) {
283 		return (ISC_R_NOTFOUND);
284 	}
285 
286 	dns_name_clone(noqname, name);
287 	dns_rdataset_clone(tneg, neg);
288 	dns_rdataset_clone(tnegsig, negsig);
289 	return (ISC_R_SUCCESS);
290 }
291 
292 isc_result_t
293 isc__rdatalist_addclosest(dns_rdataset_t *rdataset, const dns_name_t *name) {
294 	dns_rdataset_t *neg = NULL;
295 	dns_rdataset_t *negsig = NULL;
296 	dns_rdataset_t *rdset;
297 	dns_ttl_t ttl;
298 
299 	REQUIRE(rdataset != NULL);
300 
301 	for (rdset = ISC_LIST_HEAD(name->list); rdset != NULL;
302 	     rdset = ISC_LIST_NEXT(rdset, link))
303 	{
304 		if (rdset->rdclass != rdataset->rdclass) {
305 			continue;
306 		}
307 		if (rdset->type == dns_rdatatype_nsec ||
308 		    rdset->type == dns_rdatatype_nsec3) {
309 			neg = rdset;
310 		}
311 	}
312 	if (neg == NULL) {
313 		return (ISC_R_NOTFOUND);
314 	}
315 
316 	for (rdset = ISC_LIST_HEAD(name->list); rdset != NULL;
317 	     rdset = ISC_LIST_NEXT(rdset, link))
318 	{
319 		if (rdset->type == dns_rdatatype_rrsig &&
320 		    rdset->covers == neg->type) {
321 			negsig = rdset;
322 		}
323 	}
324 
325 	if (negsig == NULL) {
326 		return (ISC_R_NOTFOUND);
327 	}
328 	/*
329 	 * Minimise ttl.
330 	 */
331 	ttl = rdataset->ttl;
332 	if (neg->ttl < ttl) {
333 		ttl = neg->ttl;
334 	}
335 	if (negsig->ttl < ttl) {
336 		ttl = negsig->ttl;
337 	}
338 	rdataset->ttl = neg->ttl = negsig->ttl = ttl;
339 	rdataset->attributes |= DNS_RDATASETATTR_CLOSEST;
340 	rdataset->private7 = name;
341 	return (ISC_R_SUCCESS);
342 }
343 
344 isc_result_t
345 isc__rdatalist_getclosest(dns_rdataset_t *rdataset, dns_name_t *name,
346 			  dns_rdataset_t *neg, dns_rdataset_t *negsig) {
347 	dns_rdataclass_t rdclass;
348 	dns_rdataset_t *tneg = NULL;
349 	dns_rdataset_t *tnegsig = NULL;
350 	const dns_name_t *closest;
351 
352 	REQUIRE(rdataset != NULL);
353 	REQUIRE((rdataset->attributes & DNS_RDATASETATTR_CLOSEST) != 0);
354 
355 	rdclass = rdataset->rdclass;
356 	closest = rdataset->private7;
357 
358 	(void)dns_name_dynamic(closest); /* Sanity Check. */
359 
360 	for (rdataset = ISC_LIST_HEAD(closest->list); rdataset != NULL;
361 	     rdataset = ISC_LIST_NEXT(rdataset, link))
362 	{
363 		if (rdataset->rdclass != rdclass) {
364 			continue;
365 		}
366 		if (rdataset->type == dns_rdatatype_nsec ||
367 		    rdataset->type == dns_rdatatype_nsec3)
368 		{
369 			tneg = rdataset;
370 		}
371 	}
372 	if (tneg == NULL) {
373 		return (ISC_R_NOTFOUND);
374 	}
375 
376 	for (rdataset = ISC_LIST_HEAD(closest->list); rdataset != NULL;
377 	     rdataset = ISC_LIST_NEXT(rdataset, link))
378 	{
379 		if (rdataset->type == dns_rdatatype_rrsig &&
380 		    rdataset->covers == tneg->type) {
381 			tnegsig = rdataset;
382 		}
383 	}
384 	if (tnegsig == NULL) {
385 		return (ISC_R_NOTFOUND);
386 	}
387 
388 	dns_name_clone(closest, name);
389 	dns_rdataset_clone(tneg, neg);
390 	dns_rdataset_clone(tnegsig, negsig);
391 	return (ISC_R_SUCCESS);
392 }
393 
394 void
395 isc__rdatalist_setownercase(dns_rdataset_t *rdataset, const dns_name_t *name) {
396 	dns_rdatalist_t *rdatalist;
397 	unsigned int i;
398 
399 	/*
400 	 * We do not need to worry about label lengths as they are all
401 	 * less than or equal to 63.
402 	 */
403 	rdatalist = rdataset->private1;
404 	memset(rdatalist->upper, 0, sizeof(rdatalist->upper));
405 	for (i = 1; i < name->length; i++) {
406 		if (name->ndata[i] >= 0x41 && name->ndata[i] <= 0x5a) {
407 			rdatalist->upper[i / 8] |= 1 << (i % 8);
408 			/*
409 			 * Record that upper has been set.
410 			 */
411 		}
412 	}
413 	/*
414 	 * Record that upper has been set.
415 	 */
416 	rdatalist->upper[0] |= 0x01;
417 }
418 
419 void
420 isc__rdatalist_getownercase(const dns_rdataset_t *rdataset, dns_name_t *name) {
421 	dns_rdatalist_t *rdatalist;
422 	unsigned int i;
423 
424 	rdatalist = rdataset->private1;
425 	if ((rdatalist->upper[0] & 0x01) == 0) {
426 		return;
427 	}
428 	for (i = 0; i < name->length; i++) {
429 		/*
430 		 * Set the case bit if it does not match the recorded bit.
431 		 */
432 		if (name->ndata[i] >= 0x61 && name->ndata[i] <= 0x7a &&
433 		    (rdatalist->upper[i / 8] & (1 << (i % 8))) != 0)
434 		{
435 			name->ndata[i] &= ~0x20; /* clear the lower case bit */
436 		} else if (name->ndata[i] >= 0x41 && name->ndata[i] <= 0x5a &&
437 			   (rdatalist->upper[i / 8] & (1 << (i % 8))) == 0)
438 		{
439 			name->ndata[i] |= 0x20; /* set the lower case bit */
440 		}
441 	}
442 }
443