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
16ldns_rr *
17ldns_zone_soa(const ldns_zone *z)
18{
19        return z->_soa;
20}
21
22size_t
23ldns_zone_rr_count(const ldns_zone *z)
24{
25	return ldns_rr_list_rr_count(z->_rrs);
26}
27
28void
29ldns_zone_set_soa(ldns_zone *z, ldns_rr *soa)
30{
31	z->_soa = soa;
32}
33
34ldns_rr_list *
35ldns_zone_rrs(const ldns_zone *z)
36{
37	return z->_rrs;
38}
39
40void
41ldns_zone_set_rrs(ldns_zone *z, ldns_rr_list *rrlist)
42{
43	z->_rrs = rrlist;
44}
45
46bool
47ldns_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
53bool
54ldns_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 */
65ldns_rr_list *
66ldns_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
152memory_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
165ldns_zone *
166ldns_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 regocnize:
185 * $TTL, $ORIGIN
186 */
187ldns_status
188ldns_zone_new_frm_fp(ldns_zone **z, FILE *fp, 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 */
194ldns_status
195ldns_zone_new_frm_fp_l(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl,
196        ldns_rr_class ATTR_UNUSED(c), int *line_nr)
197{
198	ldns_zone *newzone;
199	ldns_rr *rr;
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
207	/* most cases of error are memory problems */
208	ret = LDNS_STATUS_MEM_ERR;
209
210	newzone = NULL;
211	my_origin = NULL;
212	my_prev = NULL;
213
214	my_ttl    = ttl;
215
216	if (origin) {
217		my_origin = ldns_rdf_clone(origin);
218		if (!my_origin) goto error;
219		/* also set the prev */
220		my_prev   = ldns_rdf_clone(origin);
221		if (!my_prev) goto error;
222	}
223
224	newzone = ldns_zone_new();
225	if (!newzone) goto error;
226
227	while(!feof(fp)) {
228		s = ldns_rr_new_frm_fp_l(&rr, fp, &my_ttl, &my_origin, &my_prev, line_nr);
229		switch (s) {
230		case LDNS_STATUS_OK:
231			if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SOA) {
232				if (soa_seen) {
233					/* second SOA
234					 * just skip, maybe we want to say
235					 * something??? */
236					ldns_rr_free(rr);
237					continue;
238				}
239				soa_seen = true;
240				ldns_zone_set_soa(newzone, rr);
241				/* set origin to soa if not specified */
242				if (!my_origin) {
243					my_origin = ldns_rdf_clone(ldns_rr_owner(rr));
244				}
245				continue;
246			}
247
248			/* a normal RR - as sofar the DNS is normal */
249			if (!ldns_zone_push_rr(newzone, rr)) goto error;
250
251		case LDNS_STATUS_SYNTAX_EMPTY:
252			/* empty line was seen */
253		case LDNS_STATUS_SYNTAX_TTL:
254			/* the function set the ttl */
255			break;
256		case LDNS_STATUS_SYNTAX_ORIGIN:
257			/* the function set the origin */
258			break;
259		case LDNS_STATUS_SYNTAX_INCLUDE:
260			ret = LDNS_STATUS_SYNTAX_INCLUDE_ERR_NOTIMPL;
261			break;
262		default:
263			ret = s;
264			goto error;
265		}
266	}
267
268	if (my_origin) {
269		ldns_rdf_deep_free(my_origin);
270	}
271	if (my_prev) {
272		ldns_rdf_deep_free(my_prev);
273	}
274	if (z) {
275		*z = newzone;
276	} else {
277		ldns_zone_free(newzone);
278	}
279
280	return LDNS_STATUS_OK;
281
282error:
283	if (my_origin) {
284		ldns_rdf_deep_free(my_origin);
285	}
286	if (my_prev) {
287		ldns_rdf_deep_free(my_prev);
288	}
289	if (newzone) {
290		ldns_zone_free(newzone);
291	}
292	return ret;
293}
294
295void
296ldns_zone_sort(ldns_zone *zone)
297{
298	ldns_rr_list *zrr;
299	assert(zone != NULL);
300
301	zrr = ldns_zone_rrs(zone);
302	ldns_rr_list_sort(zrr);
303}
304
305void
306ldns_zone_free(ldns_zone *zone)
307{
308	ldns_rr_list_free(zone->_rrs);
309	LDNS_FREE(zone);
310}
311
312void
313ldns_zone_deep_free(ldns_zone *zone)
314{
315	ldns_rr_free(zone->_soa);
316	ldns_rr_list_deep_free(zone->_rrs);
317	LDNS_FREE(zone);
318}
319