xref: /dragonfly/contrib/ldns/zone.c (revision d4ef6694)
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 /* return a clone of the given rr list, without the glue records
60  * rr list should be the complete zone
61  * if present, stripped records are added to the list *glue_records
62  */
63 ldns_rr_list *
64 ldns_zone_strip_glue_rrs(const ldns_rdf *zone_name, const ldns_rr_list *rrs, ldns_rr_list *glue_rrs)
65 {
66 	ldns_rr_list *new_list;
67 
68 	/* when do we find glue? It means we find an IP address
69 	 * (AAAA/A) for a nameserver listed in the zone
70 	 *
71 	 * Alg used here:
72 	 * first find all the zonecuts (NS records)
73 	 * find all the AAAA or A records (can be done it the
74 	 * above loop).
75 	 *
76 	 * Check if the aaaa/a list are subdomains under the
77 	 * NS domains.
78 	 * If yes -> glue, if no -> not glue
79 	 */
80 
81 	ldns_rr_list *zone_cuts;
82 	ldns_rr_list *addr;
83 	ldns_rr *r, *ns, *a;
84 	ldns_rdf *dname_a, *ns_owner;
85 	uint16_t i,j;
86 
87 	new_list = NULL;
88 	zone_cuts = NULL;
89 	addr = NULL;
90 
91 	new_list = ldns_rr_list_new();
92 	if (!new_list) goto memory_error;
93 	zone_cuts = ldns_rr_list_new();
94 	if (!zone_cuts) goto memory_error;
95 	addr = ldns_rr_list_new();
96 	if (!addr) goto memory_error;
97 
98 	for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
99 		r = ldns_rr_list_rr(rrs, i);
100 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
101 				ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
102 			/* possibly glue */
103 			if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
104 			continue;
105 		}
106 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
107 			/* multiple zones will end up here -
108 			 * for now; not a problem
109 			 */
110 			/* don't add NS records for the current zone itself */
111 			if (ldns_rdf_compare(ldns_rr_owner(r),
112 						zone_name) != 0) {
113 				if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
114 			}
115 			continue;
116 		}
117 	}
118 
119 	/* will sorting make it quicker ?? */
120 	for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
121 		ns = ldns_rr_list_rr(zone_cuts, i);
122 		ns_owner = ldns_rr_owner(ns);
123 		for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
124 			a = ldns_rr_list_rr(addr, j);
125 			dname_a = ldns_rr_owner(a);
126 
127 			if (ldns_dname_is_subdomain(dname_a, ns_owner)) {
128 				/* GLUE! */
129 				if (glue_rrs) {
130 					if (!ldns_rr_list_push_rr(glue_rrs, a)) goto memory_error;
131 				}
132 				break;
133 			} else {
134 				if (!ldns_rr_list_push_rr(new_list, a)) goto memory_error;
135 			}
136 		}
137 	}
138 
139 	ldns_rr_list_free(addr);
140 	ldns_rr_list_free(zone_cuts);
141 
142 	return new_list;
143 
144 memory_error:
145 	if (new_list) {
146 		ldns_rr_list_free(new_list);
147 	}
148 	if (zone_cuts) {
149 		ldns_rr_list_free(zone_cuts);
150 	}
151 	if (addr) {
152 		ldns_rr_list_free(addr);
153 	}
154 	return NULL;
155 }
156 
157 /*
158  * Get the list of glue records in a zone
159  * XXX: there should be a way for this to return error, other than NULL,
160  *      since NULL is a valid return
161  */
162 ldns_rr_list *
163 ldns_zone_glue_rr_list(const ldns_zone *z)
164 {
165 	/* when do we find glue? It means we find an IP address
166 	 * (AAAA/A) for a nameserver listed in the zone
167 	 *
168 	 * Alg used here:
169 	 * first find all the zonecuts (NS records)
170 	 * find all the AAAA or A records (can be done it the
171 	 * above loop).
172 	 *
173 	 * Check if the aaaa/a list are subdomains under the
174 	 * NS domains.
175 	 * If yes -> glue, if no -> not glue
176 	 */
177 
178 	ldns_rr_list *zone_cuts;
179 	ldns_rr_list *addr;
180 	ldns_rr_list *glue;
181 	ldns_rr *r, *ns, *a;
182 	ldns_rdf *dname_a, *ns_owner;
183 	size_t i,j;
184 
185 	zone_cuts = NULL;
186 	addr = NULL;
187 	glue = NULL;
188 
189 	/* we cannot determine glue in a 'zone' without a SOA */
190 	if (!ldns_zone_soa(z)) {
191 		return NULL;
192 	}
193 
194 	zone_cuts = ldns_rr_list_new();
195 	if (!zone_cuts) goto memory_error;
196 	addr = ldns_rr_list_new();
197 	if (!addr) goto memory_error;
198 	glue = ldns_rr_list_new();
199 	if (!glue) goto memory_error;
200 
201 	for(i = 0; i < ldns_zone_rr_count(z); i++) {
202 		r = ldns_rr_list_rr(ldns_zone_rrs(z), i);
203 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
204 				ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
205 			/* possibly glue */
206 			if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
207 			continue;
208 		}
209 		if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
210 			/* multiple zones will end up here -
211 			 * for now; not a problem
212 			 */
213 			/* don't add NS records for the current zone itself */
214 			if (ldns_rdf_compare(ldns_rr_owner(r),
215 						ldns_rr_owner(ldns_zone_soa(z))) != 0) {
216 				if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
217 			}
218 			continue;
219 		}
220 	}
221 
222 	/* will sorting make it quicker ?? */
223 	for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
224 		ns = ldns_rr_list_rr(zone_cuts, i);
225 		ns_owner = ldns_rr_owner(ns);
226 
227 		for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
228 			a = ldns_rr_list_rr(addr, j);
229 			dname_a = ldns_rr_owner(a);
230 
231 			if (ldns_dname_is_subdomain(dname_a, ns_owner) ||
232 				ldns_dname_compare(dname_a, ns_owner) == 0) {
233 				/* GLUE! */
234 				if (!ldns_rr_list_push_rr(glue, a)) goto memory_error;
235 			}
236 		}
237 	}
238 
239 	ldns_rr_list_free(addr);
240 	ldns_rr_list_free(zone_cuts);
241 
242 	if (ldns_rr_list_rr_count(glue) == 0) {
243 		ldns_rr_list_free(glue);
244 		return NULL;
245 	} else {
246 		return glue;
247 	}
248 
249 memory_error:
250 	if (zone_cuts) {
251 		LDNS_FREE(zone_cuts);
252 	}
253 	if (addr) {
254 		ldns_rr_list_free(addr);
255 	}
256 	if (glue) {
257 		ldns_rr_list_free(glue);
258 	}
259 	return NULL;
260 }
261 
262 ldns_zone *
263 ldns_zone_new(void)
264 {
265 	ldns_zone *z;
266 
267 	z = LDNS_MALLOC(ldns_zone);
268 	if (!z) {
269 		return NULL;
270 	}
271 
272 	z->_rrs = ldns_rr_list_new();
273 	if (!z->_rrs) {
274 		LDNS_FREE(z);
275 		return NULL;
276 	}
277 	ldns_zone_set_soa(z, NULL);
278 	return z;
279 }
280 
281 /* we regocnize:
282  * $TTL, $ORIGIN
283  */
284 ldns_status
285 ldns_zone_new_frm_fp(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl, ldns_rr_class c)
286 {
287 	return ldns_zone_new_frm_fp_l(z, fp, origin, ttl, c, NULL);
288 }
289 
290 /* XXX: class is never used */
291 ldns_status
292 ldns_zone_new_frm_fp_l(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl,
293         ldns_rr_class ATTR_UNUSED(c), int *line_nr)
294 {
295 	ldns_zone *newzone;
296 	ldns_rr *rr;
297 	uint32_t my_ttl;
298 	ldns_rdf *my_origin;
299 	ldns_rdf *my_prev;
300 	bool soa_seen = false; 	/* 2 soa are an error */
301 	ldns_status s;
302 	ldns_status ret;
303 
304 	/* most cases of error are memory problems */
305 	ret = LDNS_STATUS_MEM_ERR;
306 
307 	newzone = NULL;
308 	my_origin = NULL;
309 	my_prev = NULL;
310 
311 	my_ttl    = ttl;
312 
313 	if (origin) {
314 		my_origin = ldns_rdf_clone(origin);
315 		if (!my_origin) goto error;
316 		/* also set the prev */
317 		my_prev   = ldns_rdf_clone(origin);
318 		if (!my_prev) goto error;
319 	}
320 
321 	newzone = ldns_zone_new();
322 	if (!newzone) goto error;
323 
324 	while(!feof(fp)) {
325 		s = ldns_rr_new_frm_fp_l(&rr, fp, &my_ttl, &my_origin, &my_prev, line_nr);
326 		switch (s) {
327 		case LDNS_STATUS_OK:
328 			if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SOA) {
329 				if (soa_seen) {
330 					/* second SOA
331 					 * just skip, maybe we want to say
332 					 * something??? */
333 					ldns_rr_free(rr);
334 					continue;
335 				}
336 				soa_seen = true;
337 				ldns_zone_set_soa(newzone, rr);
338 				/* set origin to soa if not specified */
339 				if (!my_origin) {
340 					my_origin = ldns_rdf_clone(ldns_rr_owner(rr));
341 				}
342 				continue;
343 			}
344 
345 			/* a normal RR - as sofar the DNS is normal */
346 			if (!ldns_zone_push_rr(newzone, rr)) goto error;
347 
348 		case LDNS_STATUS_SYNTAX_EMPTY:
349 			/* empty line was seen */
350 		case LDNS_STATUS_SYNTAX_TTL:
351 			/* the function set the ttl */
352 			break;
353 		case LDNS_STATUS_SYNTAX_ORIGIN:
354 			/* the function set the origin */
355 			break;
356 		case LDNS_STATUS_SYNTAX_INCLUDE:
357 			ret = LDNS_STATUS_SYNTAX_INCLUDE_ERR_NOTIMPL;
358 			break;
359 		default:
360 			ret = s;
361 			goto error;
362 		}
363 	}
364 
365 	if (my_origin) {
366 		ldns_rdf_deep_free(my_origin);
367 	}
368 	if (my_prev) {
369 		ldns_rdf_deep_free(my_prev);
370 	}
371 	if (z) {
372 		*z = newzone;
373 	} else {
374 		ldns_zone_free(newzone);
375 	}
376 
377 	return LDNS_STATUS_OK;
378 
379 error:
380 	if (my_origin) {
381 		ldns_rdf_deep_free(my_origin);
382 	}
383 	if (my_prev) {
384 		ldns_rdf_deep_free(my_prev);
385 	}
386 	if (newzone) {
387 		ldns_zone_free(newzone);
388 	}
389 	return ret;
390 }
391 
392 void
393 ldns_zone_sort(ldns_zone *zone)
394 {
395 	ldns_rr_list *zrr;
396 	assert(zone != NULL);
397 
398 	zrr = ldns_zone_rrs(zone);
399 	ldns_rr_list_sort(zrr);
400 }
401 
402 #if 0
403 /**
404  * ixfr function. Work on a ldns_zone and remove and add
405  * the rrs from the rrlist
406  * \param[in] z the zone to work on
407  * \param[in] del rr_list to remove from the zone
408  * \param[in] add rr_list to add to the zone
409  * \return Tja, wat zouden we eens returnen TODO
410  */
411 void
412 ldns_zone_ixfr_del_add(ldns_zone *z, ldns_rr_list *del, ldns_rr_list *add)
413 {
414 
415 }
416 #endif
417 
418 void
419 ldns_zone_free(ldns_zone *zone)
420 {
421 	ldns_rr_list_free(zone->_rrs);
422 	LDNS_FREE(zone);
423 }
424 
425 void
426 ldns_zone_deep_free(ldns_zone *zone)
427 {
428 	ldns_rr_free(zone->_soa);
429 	ldns_rr_list_deep_free(zone->_rrs);
430 	LDNS_FREE(zone);
431 }
432