1/*
2 * higher.c
3 *
4 * Specify some higher level functions that would
5 * be useful to would be developers
6 *
7 * a Net::DNS like library for C
8 *
9 * (c) NLnet Labs, 2004-2006
10 *
11 * See the file LICENSE for the license
12 */
13
14#include <ldns/config.h>
15
16#include <ldns/ldns.h>
17
18#ifdef HAVE_SSL
19#include <openssl/ssl.h>
20#include <openssl/sha.h>
21#endif /* HAVE_SSL */
22
23ldns_rr_list *
24ldns_get_rr_list_addr_by_name(ldns_resolver *res, const ldns_rdf *name,
25		ldns_rr_class c, uint16_t flags)
26{
27	ldns_pkt *pkt;
28	ldns_rr_list *aaaa;
29	ldns_rr_list *a;
30	ldns_rr_list *result = NULL;
31	ldns_rr_list *hostsfilenames;
32	size_t i;
33	uint8_t ip6;
34
35	a = NULL;
36	aaaa = NULL;
37	result = NULL;
38
39	if (!res) {
40		return NULL;
41	}
42	if (ldns_rdf_get_type(name) != LDNS_RDF_TYPE_DNAME) {
43		return NULL;
44	}
45
46	ip6 = ldns_resolver_ip6(res); /* we use INET_ANY here, save
47					 what was there */
48
49	ldns_resolver_set_ip6(res, LDNS_RESOLV_INETANY);
50
51	hostsfilenames = ldns_get_rr_list_hosts_frm_file(NULL);
52	for (i = 0; i < ldns_rr_list_rr_count(hostsfilenames); i++) {
53		if (ldns_rdf_compare(name,
54					ldns_rr_owner(ldns_rr_list_rr(hostsfilenames,
55							i))) == 0) {
56			if (!result) {
57				result = ldns_rr_list_new();
58			}
59			ldns_rr_list_push_rr(result,
60					ldns_rr_clone(ldns_rr_list_rr(hostsfilenames, i)));
61		}
62	}
63	ldns_rr_list_deep_free(hostsfilenames);
64
65	if (result) {
66		return result;
67	}
68
69	/* add the RD flags, because we want an answer */
70	pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_AAAA, c, flags | LDNS_RD);
71	if (pkt) {
72		/* extract the data we need */
73		aaaa = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_AAAA,
74			LDNS_SECTION_ANSWER);
75		ldns_pkt_free(pkt);
76	}
77
78	pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_A, c, flags | LDNS_RD);
79	if (pkt) {
80		/* extract the data we need */
81		a = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_A, LDNS_SECTION_ANSWER);
82		ldns_pkt_free(pkt);
83	}
84	ldns_resolver_set_ip6(res, ip6);
85
86	if (aaaa && a) {
87		result = ldns_rr_list_cat_clone(aaaa, a);
88		ldns_rr_list_deep_free(aaaa);
89		ldns_rr_list_deep_free(a);
90		return result;
91	}
92
93	if (aaaa) {
94		result = ldns_rr_list_clone(aaaa);
95	}
96
97	if (a) {
98		result = ldns_rr_list_clone(a);
99	}
100
101	ldns_rr_list_deep_free(aaaa);
102	ldns_rr_list_deep_free(a);
103	return result;
104}
105
106ldns_rr_list *
107ldns_get_rr_list_name_by_addr(ldns_resolver *res, const ldns_rdf *addr,
108		ldns_rr_class c, uint16_t flags)
109{
110	ldns_pkt *pkt;
111	ldns_rr_list *names;
112	ldns_rdf *name;
113
114	names = NULL;
115
116	if (!res || !addr) {
117		return NULL;
118	}
119
120	if (ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_A &&
121			ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_AAAA) {
122		return NULL;
123	}
124
125	name = ldns_rdf_address_reverse(addr);
126
127	/* add the RD flags, because we want an answer */
128	pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_PTR, c, flags | LDNS_RD);
129	ldns_rdf_deep_free(name);
130	if (pkt) {
131		/* extract the data we need */
132		names = ldns_pkt_rr_list_by_type(pkt,
133				LDNS_RR_TYPE_PTR, LDNS_SECTION_ANSWER);
134		ldns_pkt_free(pkt);
135	}
136	return names;
137}
138
139/* read a line, put it in a buffer, parse the buffer */
140ldns_rr_list *
141ldns_get_rr_list_hosts_frm_fp(FILE *fp)
142{
143	return ldns_get_rr_list_hosts_frm_fp_l(fp, NULL);
144}
145
146ldns_rr_list *
147ldns_get_rr_list_hosts_frm_fp_l(FILE *fp, int *line_nr)
148{
149	ssize_t i, j;
150	size_t cnt;
151	char *line;
152	char *word;
153	char *addr;
154	char *rr_str;
155	ldns_buffer *linebuf;
156	ldns_rr *rr;
157	ldns_rr_list *list;
158	ldns_rdf *tmp;
159	bool ip6;
160	ldns_status parse_result;
161
162	line = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
163	word = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
164	addr = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
165	rr_str = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
166	ip6 = false;
167	list = ldns_rr_list_new();
168	rr = NULL;
169	if(!line || !word || !addr || !rr_str || !list) {
170		LDNS_FREE(line);
171		LDNS_FREE(word);
172		LDNS_FREE(addr);
173		LDNS_FREE(rr_str);
174		ldns_rr_list_free(list);
175		return NULL;
176	}
177
178	for(i = ldns_fget_token_l(fp, line, "\n", LDNS_MAX_LINELEN, line_nr);
179			i > 0; i = ldns_fget_token_l(fp, line, "\n", LDNS_MAX_LINELEN, line_nr)) {
180		/* # is comment */
181		if (line[0] == '#') {
182			continue;
183		}
184		/* put it in a buffer for further processing */
185		linebuf = LDNS_MALLOC(ldns_buffer);
186		if(!linebuf) {
187			LDNS_FREE(line);
188			LDNS_FREE(word);
189			LDNS_FREE(addr);
190			LDNS_FREE(rr_str);
191			ldns_rr_list_deep_free(list);
192			return NULL;
193		}
194
195		ldns_buffer_new_frm_data(linebuf, line, (size_t) i);
196		for(cnt = 0, j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, LDNS_MAX_LINELEN);
197				j > 0;
198				j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, LDNS_MAX_LINELEN), cnt++) {
199			if (cnt == 0) {
200				/* the address */
201				if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA,
202								word))) {
203					/* ip6 */
204					ldns_rdf_deep_free(tmp);
205					ip6 = true;
206				} else {
207					if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A,
208									word))) {
209						/* ip4 */
210						ldns_rdf_deep_free(tmp);
211						ip6 = false;
212					} else {
213						/* kaput */
214						break;
215					}
216				}
217				(void)strlcpy(addr, word, LDNS_MAX_LINELEN+1);
218			} else {
219				/* Stop parsing line when a comment begins. */
220				if (word[0] == '#')
221					break;
222				/* la al la la */
223				if (ip6) {
224					snprintf(rr_str, LDNS_MAX_LINELEN,
225						"%s IN AAAA %s", word, addr);
226				} else {
227					snprintf(rr_str, LDNS_MAX_LINELEN,
228						"%s IN A %s", word, addr);
229				}
230				parse_result = ldns_rr_new_frm_str(&rr, rr_str, 0, NULL, NULL);
231				if (parse_result == LDNS_STATUS_OK && ldns_rr_owner(rr) && ldns_rr_rd_count(rr) > 0) {
232					ldns_rr_list_push_rr(list, ldns_rr_clone(rr));
233					ldns_rr_free(rr);
234				}
235			}
236		}
237		ldns_buffer_free(linebuf);
238	}
239	LDNS_FREE(line);
240	LDNS_FREE(word);
241	LDNS_FREE(addr);
242	LDNS_FREE(rr_str);
243	return list;
244}
245
246ldns_rr_list *
247ldns_get_rr_list_hosts_frm_file(char *filename)
248{
249	ldns_rr_list *names;
250	FILE *fp;
251
252	if (!filename) {
253                fp = fopen(LDNS_RESOLV_HOSTS, "r");
254
255        } else {
256                fp = fopen(filename, "r");
257        }
258        if (!fp) {
259                return NULL;
260        }
261
262	names = ldns_get_rr_list_hosts_frm_fp(fp);
263	fclose(fp);
264	return names;
265}
266
267uint16_t
268ldns_getaddrinfo(ldns_resolver *res, const ldns_rdf *node,
269		ldns_rr_class c, ldns_rr_list **ret)
270{
271	ldns_rdf_type t;
272	uint16_t names_found;
273	ldns_resolver *r;
274	ldns_status s;
275
276	t = ldns_rdf_get_type(node);
277	names_found = 0;
278	r = res;
279
280	if (res == NULL) {
281		/* prepare a new resolver, using /etc/resolv.conf as a guide  */
282		s = ldns_resolver_new_frm_file(&r, NULL);
283		if (s != LDNS_STATUS_OK) {
284			return 0;
285		}
286	}
287
288	if (t == LDNS_RDF_TYPE_DNAME) {
289		/* we're asked to query for a name */
290		*ret = ldns_get_rr_list_addr_by_name(r, node, c, 0);
291		names_found = ldns_rr_list_rr_count(*ret);
292	}
293
294	if (t == LDNS_RDF_TYPE_A || t == LDNS_RDF_TYPE_AAAA) {
295		/* an address */
296		*ret = ldns_get_rr_list_name_by_addr(r, node, c, 0);
297		names_found = ldns_rr_list_rr_count(*ret);
298	}
299
300	if (res == NULL) {
301		ldns_resolver_deep_free(r);
302	}
303
304	return names_found;
305}
306
307bool
308ldns_nsec_type_check(const ldns_rr *nsec, ldns_rr_type t)
309{
310	switch (ldns_rr_get_type(nsec)) {
311	case LDNS_RR_TYPE_NSEC	: if (ldns_rr_rd_count(nsec) < 2) {
312					  return false;
313				  }
314				  return ldns_nsec_bitmap_covers_type(
315						  ldns_rr_rdf(nsec, 1), t);
316
317	case LDNS_RR_TYPE_NSEC3	: if (ldns_rr_rd_count(nsec) < 6) {
318					  return false;
319				  }
320				  return ldns_nsec_bitmap_covers_type(
321						  ldns_rr_rdf(nsec, 5), t);
322
323	default			: return false;
324	}
325}
326
327void
328ldns_print_rr_rdf(FILE *fp, ldns_rr *r, int rdfnum, ...)
329{
330	int16_t rdf;
331	ldns_rdf *rd;
332	va_list va_rdf;
333	va_start(va_rdf, rdfnum);
334
335	for (rdf = (int16_t)rdfnum; rdf != -1; rdf = (int16_t)va_arg(va_rdf, int))
336	{
337		rd = ldns_rr_rdf(r, rdf);
338		if (!rd) {
339			continue;
340		} else {
341			ldns_rdf_print(fp, rd);
342			fprintf(fp, " "); /* not sure if we want to do this */
343		}
344	}
345	va_end(va_rdf);
346}
347
348