xref: /dragonfly/lib/libssh/openbsd-compat/getrrsetbyname-ldns.c (revision e926d9f338dd5529d4bd857f7ac14e0a32ea0ab1)
1 /* $OpenBSD: getrrsetbyname.c,v 1.10 2005/03/30 02:58:28 tedu Exp $ */
2 
3 /*
4  * Copyright (c) 2007 Simon Vallet / Genoscope <svallet@genoscope.cns.fr>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * Portions Copyright (c) 1999-2001 Internet Software Consortium.
31  *
32  * Permission to use, copy, modify, and distribute this software for any
33  * purpose with or without fee is hereby granted, provided that the above
34  * copyright notice and this permission notice appear in all copies.
35  *
36  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
37  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
39  * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
40  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
41  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
42  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
43  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
44  */
45 
46 #include "includes.h"
47 
48 #if !defined (HAVE_GETRRSETBYNAME) && defined (HAVE_LDNS)
49 
50 #include <stdlib.h>
51 #include <string.h>
52 
53 #include <ldns/ldns.h>
54 
55 #include "getrrsetbyname.h"
56 #include "log.h"
57 #include "xmalloc.h"
58 
59 #define malloc(x)   (xmalloc(x))
60 #define calloc(x, y)          (xcalloc((x),(y)))
61 
62 int
getrrsetbyname(const char * hostname,unsigned int rdclass,unsigned int rdtype,unsigned int flags,struct rrsetinfo ** res)63 getrrsetbyname(const char *hostname, unsigned int rdclass,
64                  unsigned int rdtype, unsigned int flags,
65                  struct rrsetinfo **res)
66 {
67           int result;
68           unsigned int i, j, index_ans, index_sig;
69           struct rrsetinfo *rrset = NULL;
70           struct rdatainfo *rdata;
71           size_t len;
72           ldns_resolver *ldns_res = NULL;
73           ldns_rdf *domain = NULL;
74           ldns_pkt *pkt = NULL;
75           ldns_rr_list *rrsigs = NULL, *rrdata = NULL;
76           ldns_status err;
77           ldns_rr *rr;
78 
79           /* check for invalid class and type */
80           if (rdclass > 0xffff || rdtype > 0xffff) {
81                     result = ERRSET_INVAL;
82                     goto fail;
83           }
84 
85           /* don't allow queries of class or type ANY */
86           if (rdclass == 0xff || rdtype == 0xff) {
87                     result = ERRSET_INVAL;
88                     goto fail;
89           }
90 
91           /* don't allow flags yet, unimplemented */
92           if (flags) {
93                     result = ERRSET_INVAL;
94                     goto fail;
95           }
96 
97           /* Initialize resolver from resolv.conf */
98           domain = ldns_dname_new_frm_str(hostname);
99           if ((err = ldns_resolver_new_frm_file(&ldns_res, NULL)) != \
100               LDNS_STATUS_OK) {
101                     result = ERRSET_FAIL;
102                     goto fail;
103           }
104 
105 #ifdef LDNS_DEBUG
106           ldns_resolver_set_debug(ldns_res, true);
107 #endif /* LDNS_DEBUG */
108 
109           ldns_resolver_set_dnssec(ldns_res, true); /* Use DNSSEC */
110 
111           /* make query */
112           pkt = ldns_resolver_query(ldns_res, domain, rdtype, rdclass, LDNS_RD);
113 
114           /*** TODO: finer errcodes -- see original **/
115           if (!pkt || ldns_pkt_ancount(pkt) < 1) {
116                     result = ERRSET_FAIL;
117                     goto fail;
118           }
119 
120           /* initialize rrset */
121           rrset = calloc(1, sizeof(struct rrsetinfo));
122           if (rrset == NULL) {
123                     result = ERRSET_NOMEMORY;
124                     goto fail;
125           }
126 
127           rrdata = ldns_pkt_rr_list_by_type(pkt, rdtype, LDNS_SECTION_ANSWER);
128           rrset->rri_nrdatas = ldns_rr_list_rr_count(rrdata);
129           if (!rrset->rri_nrdatas) {
130                     result = ERRSET_NODATA;
131                     goto fail;
132           }
133 
134           /* copy name from answer section */
135           len = ldns_rdf_size(ldns_rr_owner(ldns_rr_list_rr(rrdata, 0)));
136           if ((rrset->rri_name = malloc(len)) == NULL) {
137                     result = ERRSET_NOMEMORY;
138                     goto fail;
139           }
140           memcpy(rrset->rri_name,
141               ldns_rdf_data(ldns_rr_owner(ldns_rr_list_rr(rrdata, 0))), len);
142 
143           rrset->rri_rdclass = ldns_rr_get_class(ldns_rr_list_rr(rrdata, 0));
144           rrset->rri_rdtype = ldns_rr_get_type(ldns_rr_list_rr(rrdata, 0));
145           rrset->rri_ttl = ldns_rr_ttl(ldns_rr_list_rr(rrdata, 0));
146 
147           debug2("ldns: got %u answers from DNS", rrset->rri_nrdatas);
148 
149           /* Check for authenticated data */
150           if (ldns_pkt_ad(pkt)) {
151                     rrset->rri_flags |= RRSET_VALIDATED;
152           } else { /* AD is not set, try autonomous validation */
153                     ldns_rr_list * trusted_keys = ldns_rr_list_new();
154 
155                     debug2("ldns: trying to validate RRset");
156                     /* Get eventual sigs */
157                     rrsigs = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_RRSIG,
158                         LDNS_SECTION_ANSWER);
159 
160                     rrset->rri_nsigs = ldns_rr_list_rr_count(rrsigs);
161                     debug2("ldns: got %u signature(s) (RRTYPE %u) from DNS",
162                            rrset->rri_nsigs, LDNS_RR_TYPE_RRSIG);
163 
164                     if ((err = ldns_verify_trusted(ldns_res, rrdata, rrsigs,
165                          trusted_keys)) == LDNS_STATUS_OK) {
166                               rrset->rri_flags |= RRSET_VALIDATED;
167                               debug2("ldns: RRset is signed with a valid key");
168                     } else {
169                               debug2("ldns: RRset validation failed: %s",
170                                   ldns_get_errorstr_by_id(err));
171                     }
172 
173                     ldns_rr_list_deep_free(trusted_keys);
174           }
175 
176           /* allocate memory for answers */
177           rrset->rri_rdatas = calloc(rrset->rri_nrdatas,
178              sizeof(struct rdatainfo));
179 
180           if (rrset->rri_rdatas == NULL) {
181                     result = ERRSET_NOMEMORY;
182                     goto fail;
183           }
184 
185           /* allocate memory for signatures */
186           if (rrset->rri_nsigs > 0) {
187                     rrset->rri_sigs = calloc(rrset->rri_nsigs,
188                         sizeof(struct rdatainfo));
189 
190                     if (rrset->rri_sigs == NULL) {
191                               result = ERRSET_NOMEMORY;
192                               goto fail;
193                     }
194           }
195 
196           /* copy answers & signatures */
197           for (i=0, index_ans=0, index_sig=0; i< pkt->_header->_ancount; i++) {
198                     rdata = NULL;
199                     rr = ldns_rr_list_rr(ldns_pkt_answer(pkt), i);
200 
201                     if (ldns_rr_get_class(rr) == rrset->rri_rdclass &&
202                         ldns_rr_get_type(rr) == rrset->rri_rdtype) {
203                               rdata = &rrset->rri_rdatas[index_ans++];
204                     }
205 
206                     if (rr->_rr_class == rrset->rri_rdclass &&
207                         rr->_rr_type == LDNS_RR_TYPE_RRSIG &&
208                         rrset->rri_sigs) {
209                               rdata = &rrset->rri_sigs[index_sig++];
210                     }
211 
212                     if (rdata) {
213                               size_t rdata_offset = 0;
214 
215                               rdata->rdi_length = 0;
216                               for (j=0; j< rr->_rd_count; j++) {
217                                         rdata->rdi_length +=
218                                             ldns_rdf_size(ldns_rr_rdf(rr, j));
219                               }
220 
221                               rdata->rdi_data = malloc(rdata->rdi_length);
222                               if (rdata->rdi_data == NULL) {
223                                         result = ERRSET_NOMEMORY;
224                                         goto fail;
225                               }
226 
227                               /* Re-create the raw DNS RDATA */
228                               for (j=0; j< rr->_rd_count; j++) {
229                                         len = ldns_rdf_size(ldns_rr_rdf(rr, j));
230                                         memcpy(rdata->rdi_data + rdata_offset,
231                                                ldns_rdf_data(ldns_rr_rdf(rr, j)), len);
232                                         rdata_offset += len;
233                               }
234                     }
235           }
236 
237           *res = rrset;
238           result = ERRSET_SUCCESS;
239 
240 fail:
241           /* freerrset(rrset); */
242           ldns_rdf_deep_free(domain);
243           ldns_pkt_free(pkt);
244           ldns_rr_list_deep_free(rrsigs);
245           ldns_rr_list_deep_free(rrdata);
246           ldns_resolver_deep_free(ldns_res);
247 
248           return result;
249 }
250 
251 
252 void
freerrset(struct rrsetinfo * rrset)253 freerrset(struct rrsetinfo *rrset)
254 {
255           u_int16_t i;
256 
257           if (rrset == NULL)
258                     return;
259 
260           if (rrset->rri_rdatas) {
261                     for (i = 0; i < rrset->rri_nrdatas; i++) {
262                               if (rrset->rri_rdatas[i].rdi_data == NULL)
263                                         break;
264                               free(rrset->rri_rdatas[i].rdi_data);
265                     }
266                     free(rrset->rri_rdatas);
267           }
268 
269           if (rrset->rri_sigs) {
270                     for (i = 0; i < rrset->rri_nsigs; i++) {
271                               if (rrset->rri_sigs[i].rdi_data == NULL)
272                                         break;
273                               free(rrset->rri_sigs[i].rdi_data);
274                     }
275                     free(rrset->rri_sigs);
276           }
277 
278           if (rrset->rri_name)
279                     free(rrset->rri_name);
280           free(rrset);
281 }
282 
283 
284 #endif /* !defined (HAVE_GETRRSETBYNAME) && defined (HAVE_LDNS) */
285