xref: /dragonfly/contrib/ldns/zone.c (revision 92fc8b5c)
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 				/* GLUE! */
233 				if (!ldns_rr_list_push_rr(glue, a)) goto memory_error;
234 			}
235 		}
236 	}
237 
238 	ldns_rr_list_free(addr);
239 	ldns_rr_list_free(zone_cuts);
240 
241 	if (ldns_rr_list_rr_count(glue) == 0) {
242 		ldns_rr_list_free(glue);
243 		return NULL;
244 	} else {
245 		return glue;
246 	}
247 
248 memory_error:
249 	if (zone_cuts) {
250 		LDNS_FREE(zone_cuts);
251 	}
252 	if (addr) {
253 		ldns_rr_list_free(addr);
254 	}
255 	if (glue) {
256 		ldns_rr_list_free(glue);
257 	}
258 	return NULL;
259 }
260 
261 ldns_zone *
262 ldns_zone_new(void)
263 {
264 	ldns_zone *z;
265 
266 	z = LDNS_MALLOC(ldns_zone);
267 	if (!z) {
268 		return NULL;
269 	}
270 
271 	z->_rrs = ldns_rr_list_new();
272 	if (!z->_rrs) {
273 		LDNS_FREE(z);
274 		return NULL;
275 	}
276 	ldns_zone_set_soa(z, NULL);
277 	return z;
278 }
279 
280 /* we regocnize:
281  * $TTL, $ORIGIN
282  */
283 ldns_status
284 ldns_zone_new_frm_fp(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl, ldns_rr_class c)
285 {
286 	return ldns_zone_new_frm_fp_l(z, fp, origin, ttl, c, NULL);
287 }
288 
289 /* XXX: class is never used */
290 ldns_status
291 ldns_zone_new_frm_fp_l(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl,
292         ldns_rr_class ATTR_UNUSED(c), int *line_nr)
293 {
294 	ldns_zone *newzone;
295 	ldns_rr *rr;
296 	uint32_t my_ttl;
297 	ldns_rdf *my_origin;
298 	ldns_rdf *my_prev;
299 	bool soa_seen = false; 	/* 2 soa are an error */
300 	ldns_status s;
301 	ldns_status ret;
302 
303 	/* most cases of error are memory problems */
304 	ret = LDNS_STATUS_MEM_ERR;
305 
306 	newzone = NULL;
307 	my_origin = NULL;
308 	my_prev = NULL;
309 
310 	my_ttl    = ttl;
311 
312 	if (origin) {
313 		my_origin = ldns_rdf_clone(origin);
314 		if (!my_origin) goto error;
315 		/* also set the prev */
316 		my_prev   = ldns_rdf_clone(origin);
317 		if (!my_prev) goto error;
318 	}
319 
320 	newzone = ldns_zone_new();
321 	if (!newzone) goto error;
322 
323 	while(!feof(fp)) {
324 		s = ldns_rr_new_frm_fp_l(&rr, fp, &my_ttl, &my_origin, &my_prev, line_nr);
325 		switch (s) {
326 		case LDNS_STATUS_OK:
327 			if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SOA) {
328 				if (soa_seen) {
329 					/* second SOA
330 					 * just skip, maybe we want to say
331 					 * something??? */
332 					ldns_rr_free(rr);
333 					continue;
334 				}
335 				soa_seen = true;
336 				ldns_zone_set_soa(newzone, rr);
337 				/* set origin to soa if not specified */
338 				if (!my_origin) {
339 					my_origin = ldns_rdf_clone(ldns_rr_owner(rr));
340 				}
341 				continue;
342 			}
343 
344 			/* a normal RR - as sofar the DNS is normal */
345 			if (!ldns_zone_push_rr(newzone, rr)) goto error;
346 
347 		case LDNS_STATUS_SYNTAX_EMPTY:
348 			/* empty line was seen */
349 		case LDNS_STATUS_SYNTAX_TTL:
350 			/* the function set the ttl */
351 			break;
352 		case LDNS_STATUS_SYNTAX_ORIGIN:
353 			/* the function set the origin */
354 			break;
355 		case LDNS_STATUS_SYNTAX_INCLUDE:
356 			ret = LDNS_STATUS_SYNTAX_INCLUDE_ERR_NOTIMPL;
357 			break;
358 		default:
359 			ret = s;
360 			goto error;
361 		}
362 	}
363 
364 	if (my_origin) {
365 		ldns_rdf_deep_free(my_origin);
366 	}
367 	if (my_prev) {
368 		ldns_rdf_deep_free(my_prev);
369 	}
370 	if (z) {
371 		*z = newzone;
372 	} else {
373 		ldns_zone_free(newzone);
374 	}
375 
376 	return LDNS_STATUS_OK;
377 
378 error:
379 	if (my_origin) {
380 		ldns_rdf_deep_free(my_origin);
381 	}
382 	if (my_prev) {
383 		ldns_rdf_deep_free(my_prev);
384 	}
385 	if (newzone) {
386 		ldns_zone_free(newzone);
387 	}
388 	return ret;
389 }
390 
391 void
392 ldns_zone_sort(ldns_zone *zone)
393 {
394 	ldns_rr_list *zrr;
395 	assert(zone != NULL);
396 
397 	zrr = ldns_zone_rrs(zone);
398 	ldns_rr_list_sort(zrr);
399 }
400 
401 #if 0
402 /**
403  * ixfr function. Work on a ldns_zone and remove and add
404  * the rrs from the rrlist
405  * \param[in] z the zone to work on
406  * \param[in] del rr_list to remove from the zone
407  * \param[in] add rr_list to add to the zone
408  * \return Tja, wat zouden we eens returnen TODO
409  */
410 void
411 ldns_zone_ixfr_del_add(ldns_zone *z, ldns_rr_list *del, ldns_rr_list *add)
412 {
413 
414 }
415 #endif
416 
417 void
418 ldns_zone_free(ldns_zone *zone)
419 {
420 	ldns_rr_list_free(zone->_rrs);
421 	LDNS_FREE(zone);
422 }
423 
424 void
425 ldns_zone_deep_free(ldns_zone *zone)
426 {
427 	ldns_rr_free(zone->_soa);
428 	ldns_rr_list_deep_free(zone->_rrs);
429 	LDNS_FREE(zone);
430 }
431