xref: /freebsd/contrib/ldns/zone.c (revision edd6bc767082254635f649f825a7f9c5f9999e85)
1 /* zone.c
2  *
3  * Functions for ldns_zone structure
4  * a Net::DNS like library for C
5  *
6  * (c) NLnet Labs, 2005-2006
7  * See the file LICENSE for the license
8  */
9 #include <ldns/config.h>
10 
11 #include <ldns/ldns.h>
12 
13 #include <strings.h>
14 #include <limits.h>
15 
16 ldns_rr *
17 ldns_zone_soa(const ldns_zone *z)
18 {
19         return z->_soa;
20 }
21 
22 size_t
23 ldns_zone_rr_count(const ldns_zone *z)
24 {
25 	return ldns_rr_list_rr_count(z->_rrs);
26 }
27 
28 void
29 ldns_zone_set_soa(ldns_zone *z, ldns_rr *soa)
30 {
31 	z->_soa = soa;
32 }
33 
34 ldns_rr_list *
35 ldns_zone_rrs(const ldns_zone *z)
36 {
37 	return z->_rrs;
38 }
39 
40 void
41 ldns_zone_set_rrs(ldns_zone *z, ldns_rr_list *rrlist)
42 {
43 	z->_rrs = rrlist;
44 }
45 
46 bool
47 ldns_zone_push_rr_list(ldns_zone *z, ldns_rr_list *list)
48 {
49 	return ldns_rr_list_cat(ldns_zone_rrs(z), list);
50 
51 }
52 
53 bool
54 ldns_zone_push_rr(ldns_zone *z, ldns_rr *rr)
55 {
56 	return ldns_rr_list_push_rr( ldns_zone_rrs(z), rr);
57 }
58 
59 #if 0
60 /* return a clone of the given rr list, without the glue records
61  * rr list should be the complete zone
62  * if present, stripped records are added to the list *glue_records
63  */
64 static ldns_rr_list *
65 ldns_zone_strip_glue_rrs(const ldns_rdf *zone_name, const ldns_rr_list *rrs, ldns_rr_list *glue_rrs)
66 {
67 	ldns_rr_list *new_list;
68 
69 	/* when do we find glue? It means we find an IP address
70 	 * (AAAA/A) for a nameserver listed in the zone
71 	 *
72 	 * Alg used here:
73 	 * first find all the zonecuts (NS records)
74 	 * find all the AAAA or A records (can be done it the
75 	 * above loop).
76 	 *
77 	 * Check if the aaaa/a list are subdomains under the
78 	 * NS domains.
79 	 * If yes -> glue, if no -> not glue
80 	 */
81 
82 	ldns_rr_list *zone_cuts;
83 	ldns_rr_list *addr;
84 	ldns_rr *r, *ns, *a;
85 	ldns_rdf *dname_a, *ns_owner;
86 	uint16_t i,j;
87 
88 	new_list = NULL;
89 	zone_cuts = NULL;
90 	addr = NULL;
91 
92 	new_list = ldns_rr_list_new();
93 	if (!new_list) goto memory_error;
94 	zone_cuts = ldns_rr_list_new();
95 	if (!zone_cuts) goto memory_error;
96 	addr = ldns_rr_list_new();
97 	if (!addr) goto memory_error;
98 
99 	for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
100 		r = ldns_rr_list_rr(rrs, i);
101 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
102 				ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
103 			/* possibly glue */
104 			if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
105 			continue;
106 		}
107 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
108 			/* multiple zones will end up here -
109 			 * for now; not a problem
110 			 */
111 			/* don't add NS records for the current zone itself */
112 			if (ldns_rdf_compare(ldns_rr_owner(r),
113 						zone_name) != 0) {
114 				if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
115 			}
116 			continue;
117 		}
118 	}
119 
120 	/* will sorting make it quicker ?? */
121 	for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
122 		ns = ldns_rr_list_rr(zone_cuts, i);
123 		ns_owner = ldns_rr_owner(ns);
124 		for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
125 			a = ldns_rr_list_rr(addr, j);
126 			dname_a = ldns_rr_owner(a);
127 
128 			if (ldns_dname_is_subdomain(dname_a, ns_owner)) {
129 				/* GLUE! */
130 				if (glue_rrs) {
131 					if (!ldns_rr_list_push_rr(glue_rrs, a)) goto memory_error;
132 				}
133 				break;
134 			} else {
135 				if (!ldns_rr_list_push_rr(new_list, a)) goto memory_error;
136 			}
137 		}
138 	}
139 
140 	ldns_rr_list_free(addr);
141 	ldns_rr_list_free(zone_cuts);
142 
143 	return new_list;
144 
145 memory_error:
146 	if (new_list) {
147 		ldns_rr_list_free(new_list);
148 	}
149 	if (zone_cuts) {
150 		ldns_rr_list_free(zone_cuts);
151 	}
152 	if (addr) {
153 		ldns_rr_list_free(addr);
154 	}
155 	return NULL;
156 }
157 #endif
158 
159 /*
160  * Get the list of glue records in a zone
161  * XXX: there should be a way for this to return error, other than NULL,
162  *      since NULL is a valid return
163  */
164 ldns_rr_list *
165 ldns_zone_glue_rr_list(const ldns_zone *z)
166 {
167 	/* when do we find glue? It means we find an IP address
168 	 * (AAAA/A) for a nameserver listed in the zone
169 	 *
170 	 * Alg used here:
171 	 * first find all the zonecuts (NS records)
172 	 * find all the AAAA or A records (can be done it the
173 	 * above loop).
174 	 *
175 	 * Check if the aaaa/a list are subdomains under the
176 	 * NS domains.
177 	 * If yes -> glue, if no -> not glue
178 	 */
179 
180 	ldns_rr_list *zone_cuts;
181 	ldns_rr_list *addr;
182 	ldns_rr_list *glue;
183 	ldns_rr *r, *ns, *a;
184 	ldns_rdf *dname_a, *ns_owner;
185 	size_t i,j;
186 
187 	zone_cuts = NULL;
188 	addr = NULL;
189 	glue = NULL;
190 
191 	/* we cannot determine glue in a 'zone' without a SOA */
192 	if (!ldns_zone_soa(z)) {
193 		return NULL;
194 	}
195 
196 	zone_cuts = ldns_rr_list_new();
197 	if (!zone_cuts) goto memory_error;
198 	addr = ldns_rr_list_new();
199 	if (!addr) goto memory_error;
200 	glue = ldns_rr_list_new();
201 	if (!glue) goto memory_error;
202 
203 	for(i = 0; i < ldns_zone_rr_count(z); i++) {
204 		r = ldns_rr_list_rr(ldns_zone_rrs(z), i);
205 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
206 				ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
207 			/* possibly glue */
208 			if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
209 			continue;
210 		}
211 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
212 			/* multiple zones will end up here -
213 			 * for now; not a problem
214 			 */
215 			/* don't add NS records for the current zone itself */
216 			if (ldns_rdf_compare(ldns_rr_owner(r),
217 						ldns_rr_owner(ldns_zone_soa(z))) != 0) {
218 				if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
219 			}
220 			continue;
221 		}
222 	}
223 
224 	/* will sorting make it quicker ?? */
225 	for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
226 		ns = ldns_rr_list_rr(zone_cuts, i);
227 		ns_owner = ldns_rr_owner(ns);
228 
229 		for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
230 			a = ldns_rr_list_rr(addr, j);
231 			dname_a = ldns_rr_owner(a);
232 
233 			if (ldns_dname_is_subdomain(dname_a, ns_owner) ||
234 				ldns_dname_compare(dname_a, ns_owner) == 0) {
235 				/* GLUE! */
236 				if (!ldns_rr_list_push_rr(glue, a)) goto memory_error;
237 			}
238 		}
239 	}
240 
241 	ldns_rr_list_free(addr);
242 	ldns_rr_list_free(zone_cuts);
243 
244 	if (ldns_rr_list_rr_count(glue) == 0) {
245 		ldns_rr_list_free(glue);
246 		return NULL;
247 	} else {
248 		return glue;
249 	}
250 
251 memory_error:
252 	if (zone_cuts) {
253 		LDNS_FREE(zone_cuts);
254 	}
255 	if (addr) {
256 		ldns_rr_list_free(addr);
257 	}
258 	if (glue) {
259 		ldns_rr_list_free(glue);
260 	}
261 	return NULL;
262 }
263 
264 ldns_zone *
265 ldns_zone_new(void)
266 {
267 	ldns_zone *z;
268 
269 	z = LDNS_MALLOC(ldns_zone);
270 	if (!z) {
271 		return NULL;
272 	}
273 
274 	z->_rrs = ldns_rr_list_new();
275 	if (!z->_rrs) {
276 		LDNS_FREE(z);
277 		return NULL;
278 	}
279 	ldns_zone_set_soa(z, NULL);
280 	return z;
281 }
282 
283 /* we regocnize:
284  * $TTL, $ORIGIN
285  */
286 ldns_status
287 ldns_zone_new_frm_fp(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl, ldns_rr_class c)
288 {
289 	return ldns_zone_new_frm_fp_l(z, fp, origin, ttl, c, NULL);
290 }
291 
292 /* XXX: class is never used */
293 ldns_status
294 ldns_zone_new_frm_fp_l(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl,
295         ldns_rr_class ATTR_UNUSED(c), int *line_nr)
296 {
297 	ldns_zone *newzone;
298 	ldns_rr *rr;
299 	uint32_t my_ttl;
300 	ldns_rdf *my_origin;
301 	ldns_rdf *my_prev;
302 	bool soa_seen = false; 	/* 2 soa are an error */
303 	ldns_status s;
304 	ldns_status ret;
305 
306 	/* most cases of error are memory problems */
307 	ret = LDNS_STATUS_MEM_ERR;
308 
309 	newzone = NULL;
310 	my_origin = NULL;
311 	my_prev = NULL;
312 
313 	my_ttl    = ttl;
314 
315 	if (origin) {
316 		my_origin = ldns_rdf_clone(origin);
317 		if (!my_origin) goto error;
318 		/* also set the prev */
319 		my_prev   = ldns_rdf_clone(origin);
320 		if (!my_prev) goto error;
321 	}
322 
323 	newzone = ldns_zone_new();
324 	if (!newzone) goto error;
325 
326 	while(!feof(fp)) {
327 		s = ldns_rr_new_frm_fp_l(&rr, fp, &my_ttl, &my_origin, &my_prev, line_nr);
328 		switch (s) {
329 		case LDNS_STATUS_OK:
330 			if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SOA) {
331 				if (soa_seen) {
332 					/* second SOA
333 					 * just skip, maybe we want to say
334 					 * something??? */
335 					ldns_rr_free(rr);
336 					continue;
337 				}
338 				soa_seen = true;
339 				ldns_zone_set_soa(newzone, rr);
340 				/* set origin to soa if not specified */
341 				if (!my_origin) {
342 					my_origin = ldns_rdf_clone(ldns_rr_owner(rr));
343 				}
344 				continue;
345 			}
346 
347 			/* a normal RR - as sofar the DNS is normal */
348 			if (!ldns_zone_push_rr(newzone, rr)) goto error;
349 
350 		case LDNS_STATUS_SYNTAX_EMPTY:
351 			/* empty line was seen */
352 		case LDNS_STATUS_SYNTAX_TTL:
353 			/* the function set the ttl */
354 			break;
355 		case LDNS_STATUS_SYNTAX_ORIGIN:
356 			/* the function set the origin */
357 			break;
358 		case LDNS_STATUS_SYNTAX_INCLUDE:
359 			ret = LDNS_STATUS_SYNTAX_INCLUDE_ERR_NOTIMPL;
360 			break;
361 		default:
362 			ret = s;
363 			goto error;
364 		}
365 	}
366 
367 	if (my_origin) {
368 		ldns_rdf_deep_free(my_origin);
369 	}
370 	if (my_prev) {
371 		ldns_rdf_deep_free(my_prev);
372 	}
373 	if (z) {
374 		*z = newzone;
375 	} else {
376 		ldns_zone_free(newzone);
377 	}
378 
379 	return LDNS_STATUS_OK;
380 
381 error:
382 	if (my_origin) {
383 		ldns_rdf_deep_free(my_origin);
384 	}
385 	if (my_prev) {
386 		ldns_rdf_deep_free(my_prev);
387 	}
388 	if (newzone) {
389 		ldns_zone_free(newzone);
390 	}
391 	return ret;
392 }
393 
394 void
395 ldns_zone_sort(ldns_zone *zone)
396 {
397 	ldns_rr_list *zrr;
398 	assert(zone != NULL);
399 
400 	zrr = ldns_zone_rrs(zone);
401 	ldns_rr_list_sort(zrr);
402 }
403 
404 #if 0
405 /**
406  * ixfr function. Work on a ldns_zone and remove and add
407  * the rrs from the rrlist
408  * \param[in] z the zone to work on
409  * \param[in] del rr_list to remove from the zone
410  * \param[in] add rr_list to add to the zone
411  * \return Tja, wat zouden we eens returnen TODO
412  */
413 void
414 ldns_zone_ixfr_del_add(ldns_zone *z, ldns_rr_list *del, ldns_rr_list *add)
415 {
416 
417 }
418 #endif
419 
420 void
421 ldns_zone_free(ldns_zone *zone)
422 {
423 	ldns_rr_list_free(zone->_rrs);
424 	LDNS_FREE(zone);
425 }
426 
427 void
428 ldns_zone_deep_free(ldns_zone *zone)
429 {
430 	ldns_rr_free(zone->_soa);
431 	ldns_rr_list_deep_free(zone->_rrs);
432 	LDNS_FREE(zone);
433 }
434