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 #include <ldns/internal.h>
13
14 #include <strings.h>
15 #include <limits.h>
16
17 ldns_rr *
ldns_zone_soa(const ldns_zone * z)18 ldns_zone_soa(const ldns_zone *z)
19 {
20 return z->_soa;
21 }
22
23 size_t
ldns_zone_rr_count(const ldns_zone * z)24 ldns_zone_rr_count(const ldns_zone *z)
25 {
26 return ldns_rr_list_rr_count(z->_rrs);
27 }
28
29 void
ldns_zone_set_soa(ldns_zone * z,ldns_rr * soa)30 ldns_zone_set_soa(ldns_zone *z, ldns_rr *soa)
31 {
32 z->_soa = soa;
33 }
34
35 ldns_rr_list *
ldns_zone_rrs(const ldns_zone * z)36 ldns_zone_rrs(const ldns_zone *z)
37 {
38 return z->_rrs;
39 }
40
41 void
ldns_zone_set_rrs(ldns_zone * z,ldns_rr_list * rrlist)42 ldns_zone_set_rrs(ldns_zone *z, ldns_rr_list *rrlist)
43 {
44 z->_rrs = rrlist;
45 }
46
47 bool
ldns_zone_push_rr_list(ldns_zone * z,const ldns_rr_list * list)48 ldns_zone_push_rr_list(ldns_zone *z, const ldns_rr_list *list)
49 {
50 return ldns_rr_list_cat(ldns_zone_rrs(z), list);
51 }
52
53 bool
ldns_zone_push_rr(ldns_zone * z,ldns_rr * rr)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
60 /*
61 * Get the list of glue records in a zone
62 * XXX: there should be a way for this to return error, other than NULL,
63 * since NULL is a valid return
64 */
65 ldns_rr_list *
ldns_zone_glue_rr_list(const ldns_zone * z)66 ldns_zone_glue_rr_list(const ldns_zone *z)
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_list *glue;
84 ldns_rr *r, *ns, *a;
85 ldns_rdf *dname_a, *ns_owner;
86 size_t i,j;
87
88 zone_cuts = NULL;
89 addr = NULL;
90 glue = NULL;
91
92 /* we cannot determine glue in a 'zone' without a SOA */
93 if (!ldns_zone_soa(z)) {
94 return NULL;
95 }
96
97 zone_cuts = ldns_rr_list_new();
98 if (!zone_cuts) goto memory_error;
99 addr = ldns_rr_list_new();
100 if (!addr) goto memory_error;
101 glue = ldns_rr_list_new();
102 if (!glue) goto memory_error;
103
104 for(i = 0; i < ldns_zone_rr_count(z); i++) {
105 r = ldns_rr_list_rr(ldns_zone_rrs(z), i);
106 if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
107 ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
108 /* possibly glue */
109 if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
110 continue;
111 }
112 if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
113 /* multiple zones will end up here -
114 * for now; not a problem
115 */
116 /* don't add NS records for the current zone itself */
117 if (ldns_rdf_compare(ldns_rr_owner(r),
118 ldns_rr_owner(ldns_zone_soa(z))) != 0) {
119 if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
120 }
121 continue;
122 }
123 }
124
125 /* will sorting make it quicker ?? */
126 for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
127 ns = ldns_rr_list_rr(zone_cuts, i);
128 ns_owner = ldns_rr_owner(ns);
129
130 for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
131 a = ldns_rr_list_rr(addr, j);
132 dname_a = ldns_rr_owner(a);
133
134 if (ldns_dname_is_subdomain(dname_a, ns_owner) ||
135 ldns_dname_compare(dname_a, ns_owner) == 0) {
136 /* GLUE! */
137 if (!ldns_rr_list_push_rr(glue, a)) goto memory_error;
138 }
139 }
140 }
141
142 ldns_rr_list_free(addr);
143 ldns_rr_list_free(zone_cuts);
144
145 if (ldns_rr_list_rr_count(glue) == 0) {
146 ldns_rr_list_free(glue);
147 return NULL;
148 } else {
149 return glue;
150 }
151
152 memory_error:
153 if (zone_cuts) {
154 LDNS_FREE(zone_cuts);
155 }
156 if (addr) {
157 ldns_rr_list_free(addr);
158 }
159 if (glue) {
160 ldns_rr_list_free(glue);
161 }
162 return NULL;
163 }
164
165 ldns_zone *
ldns_zone_new(void)166 ldns_zone_new(void)
167 {
168 ldns_zone *z;
169
170 z = LDNS_MALLOC(ldns_zone);
171 if (!z) {
172 return NULL;
173 }
174
175 z->_rrs = ldns_rr_list_new();
176 if (!z->_rrs) {
177 LDNS_FREE(z);
178 return NULL;
179 }
180 ldns_zone_set_soa(z, NULL);
181 return z;
182 }
183
184 /* we recognize:
185 * $TTL, $ORIGIN
186 */
187 ldns_status
ldns_zone_new_frm_fp(ldns_zone ** z,FILE * fp,const ldns_rdf * origin,uint32_t ttl,ldns_rr_class c)188 ldns_zone_new_frm_fp(ldns_zone **z, FILE *fp, const ldns_rdf *origin, uint32_t ttl, ldns_rr_class c)
189 {
190 return ldns_zone_new_frm_fp_l(z, fp, origin, ttl, c, NULL);
191 }
192
193 /* XXX: class is never used */
194 ldns_status
ldns_zone_new_frm_fp_l(ldns_zone ** z,FILE * fp,const ldns_rdf * origin,uint32_t default_ttl,ldns_rr_class ATTR_UNUSED (c),int * line_nr)195 ldns_zone_new_frm_fp_l(ldns_zone **z, FILE *fp, const ldns_rdf *origin,
196 uint32_t default_ttl, ldns_rr_class ATTR_UNUSED(c), int *line_nr)
197 {
198 ldns_zone *newzone;
199 ldns_rr *rr, *prev_rr = NULL;
200 uint32_t my_ttl;
201 ldns_rdf *my_origin;
202 ldns_rdf *my_prev;
203 bool soa_seen = false; /* 2 soa are an error */
204 ldns_status s;
205 ldns_status ret;
206 /* RFC 1035 Section 5.1, says 'Omitted class and TTL values are default
207 * to the last explicitly stated values.'
208 */
209 bool ttl_from_TTL = false;
210 bool explicit_ttl = false;
211
212 /* most cases of error are memory problems */
213 ret = LDNS_STATUS_MEM_ERR;
214
215 newzone = NULL;
216 my_origin = NULL;
217 my_prev = NULL;
218
219 my_ttl = default_ttl;
220
221 if (origin) {
222 my_origin = ldns_rdf_clone(origin);
223 if (!my_origin) goto error;
224 /* also set the prev */
225 my_prev = ldns_rdf_clone(origin);
226 if (!my_prev) goto error;
227 }
228
229 newzone = ldns_zone_new();
230 if (!newzone) goto error;
231
232 while(!feof(fp)) {
233 /* If ttl came from $TTL line, then it should be the default.
234 * (RFC 2308 Section 4)
235 * Otherwise it "defaults to the last explicitly stated value"
236 * (RFC 1035 Section 5.1)
237 */
238 if (ttl_from_TTL)
239 my_ttl = default_ttl;
240 s = _ldns_rr_new_frm_fp_l_internal(&rr, fp, &my_ttl, &my_origin,
241 &my_prev, line_nr, &explicit_ttl);
242 switch (s) {
243 case LDNS_STATUS_OK:
244 if (explicit_ttl) {
245 if (!ttl_from_TTL) {
246 /* No $TTL, so ttl "defaults to the
247 * last explicitly stated value"
248 * (RFC 1035 Section 5.1)
249 */
250 my_ttl = ldns_rr_ttl(rr);
251 }
252 /* When ttl is implicit, try to adhere to the rules as
253 * much as possible. (also for compatibility with bind)
254 * This was changed when fixing an issue with ZONEMD
255 * which hashes the TTL too.
256 */
257 } else if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SIG
258 || ldns_rr_get_type(rr) == LDNS_RR_TYPE_RRSIG) {
259 if (ldns_rr_rd_count(rr) >= 4
260 && ldns_rdf_get_type(ldns_rr_rdf(rr, 3)) == LDNS_RDF_TYPE_INT32)
261
262 /* SIG without explicit ttl get ttl
263 * from the original_ttl field
264 * (RFC 2535 Section 7.2)
265 *
266 * Similarly for RRSIG, but stated less
267 * specifically in the spec.
268 * (RFC 4034 Section 3)
269 */
270 ldns_rr_set_ttl(rr,
271 ldns_rdf2native_int32(
272 ldns_rr_rdf(rr, 3)));
273
274 } else if (prev_rr
275 && ldns_rr_get_type(prev_rr) == ldns_rr_get_type(rr)
276 && ldns_dname_compare( ldns_rr_owner(prev_rr)
277 , ldns_rr_owner(rr)) == 0)
278
279 /* "TTLs of all RRs in an RRSet must be the same"
280 * (RFC 2881 Section 5.2)
281 */
282 ldns_rr_set_ttl(rr, ldns_rr_ttl(prev_rr));
283
284 prev_rr = rr;
285 if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SOA) {
286 if (soa_seen) {
287 /* second SOA
288 * just skip, maybe we want to say
289 * something??? */
290 ldns_rr_free(rr);
291 continue;
292 }
293 soa_seen = true;
294 ldns_zone_set_soa(newzone, rr);
295 /* set origin to soa if not specified */
296 if (!my_origin) {
297 my_origin = ldns_rdf_clone(ldns_rr_owner(rr));
298 }
299 continue;
300 }
301
302 /* a normal RR - as sofar the DNS is normal */
303 if (!ldns_zone_push_rr(newzone, rr)) {
304 ldns_rr_free(rr);
305 goto error;
306 }
307 break;
308
309 case LDNS_STATUS_SYNTAX_EMPTY:
310 /* empty line was seen */
311 case LDNS_STATUS_SYNTAX_TTL:
312 /* the function set the ttl */
313 default_ttl = my_ttl;
314 ttl_from_TTL = true;
315 break;
316 case LDNS_STATUS_SYNTAX_ORIGIN:
317 /* the function set the origin */
318 break;
319 case LDNS_STATUS_SYNTAX_INCLUDE:
320 ret = LDNS_STATUS_SYNTAX_INCLUDE_ERR_NOTIMPL;
321 goto error;
322 default:
323 ret = s;
324 goto error;
325 }
326 }
327
328 if (my_origin) {
329 ldns_rdf_deep_free(my_origin);
330 }
331 if (my_prev) {
332 ldns_rdf_deep_free(my_prev);
333 }
334 if (z) {
335 *z = newzone;
336 } else {
337 ldns_zone_free(newzone);
338 }
339
340 return LDNS_STATUS_OK;
341
342 error:
343 if (my_origin) {
344 ldns_rdf_deep_free(my_origin);
345 }
346 if (my_prev) {
347 ldns_rdf_deep_free(my_prev);
348 }
349 if (newzone) {
350 ldns_zone_free(newzone);
351 }
352 return ret;
353 }
354
355 void
ldns_zone_sort(ldns_zone * zone)356 ldns_zone_sort(ldns_zone *zone)
357 {
358 ldns_rr_list *zrr;
359 assert(zone != NULL);
360
361 zrr = ldns_zone_rrs(zone);
362 ldns_rr_list_sort(zrr);
363 }
364
365 void
ldns_zone_free(ldns_zone * zone)366 ldns_zone_free(ldns_zone *zone)
367 {
368 ldns_rr_list_free(zone->_rrs);
369 LDNS_FREE(zone);
370 }
371
372 void
ldns_zone_deep_free(ldns_zone * zone)373 ldns_zone_deep_free(ldns_zone *zone)
374 {
375 ldns_rr_free(zone->_soa);
376 ldns_rr_list_deep_free(zone->_rrs);
377 LDNS_FREE(zone);
378 }
379