1 /*
2  * Copyright (C) 2004-2007, 2009, 2013-2016  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 2000, 2001, 2003  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id: lwdgrbn.c,v 1.22 2009/09/02 23:48:01 tbox Exp $ */
19 
20 /*! \file */
21 
22 #include <config.h>
23 
24 #include <isc/mem.h>
25 #include <isc/socket.h>
26 #include <isc/string.h>		/* Required for HP/UX (and others?) */
27 #include <isc/util.h>
28 
29 #include <dns/db.h>
30 #include <dns/lookup.h>
31 #include <dns/rdata.h>
32 #include <dns/rdataset.h>
33 #include <dns/rdatasetiter.h>
34 #include <dns/result.h>
35 #include <dns/view.h>
36 
37 #include <named/types.h>
38 #include <named/lwdclient.h>
39 #include <named/lwresd.h>
40 #include <named/lwsearch.h>
41 
42 static void start_lookup(ns_lwdclient_t *);
43 
44 static isc_result_t
fill_array(int * pos,dns_rdataset_t * rdataset,int size,unsigned char ** rdatas,lwres_uint16_t * rdatalen)45 fill_array(int *pos, dns_rdataset_t *rdataset,
46 	   int size, unsigned char **rdatas, lwres_uint16_t *rdatalen)
47 {
48 	dns_rdata_t rdata;
49 	isc_result_t result;
50 	isc_region_t r;
51 
52 	UNUSED(size);
53 
54 	dns_rdata_init(&rdata);
55 	for (result = dns_rdataset_first(rdataset);
56 	     result == ISC_R_SUCCESS;
57 	     result = dns_rdataset_next(rdataset))
58 	{
59 		INSIST(*pos < size);
60 		dns_rdataset_current(rdataset, &rdata);
61 		dns_rdata_toregion(&rdata, &r);
62 		rdatas[*pos] = r.base;
63 		rdatalen[*pos] = r.length;
64 		dns_rdata_reset(&rdata);
65 		(*pos)++;
66 	}
67 	if (result == ISC_R_NOMORE)
68 		result = ISC_R_SUCCESS;
69 	return (result);
70 }
71 
72 static isc_result_t
iterate_node(lwres_grbnresponse_t * grbn,dns_db_t * db,dns_dbnode_t * node,isc_mem_t * mctx)73 iterate_node(lwres_grbnresponse_t *grbn, dns_db_t *db, dns_dbnode_t *node,
74 	     isc_mem_t *mctx)
75 {
76 	int used = 0, count;
77 	int size = 8, oldsize = 0;
78 	unsigned char **rdatas = NULL, **oldrdatas = NULL, **newrdatas = NULL;
79 	lwres_uint16_t *lens = NULL, *oldlens = NULL, *newlens = NULL;
80 	dns_rdatasetiter_t *iter = NULL;
81 	dns_rdataset_t set;
82 	dns_ttl_t ttl = ISC_INT32_MAX;
83 	lwres_uint32_t flags = LWRDATA_VALIDATED;
84 	isc_result_t result = ISC_R_NOMEMORY;
85 
86 	result = dns_db_allrdatasets(db, node, NULL, 0, &iter);
87 	if (result != ISC_R_SUCCESS)
88 		goto out;
89 
90 	rdatas = isc_mem_get(mctx, size * sizeof(*rdatas));
91 	if (rdatas == NULL)
92 		goto out;
93 	lens = isc_mem_get(mctx, size * sizeof(*lens));
94 	if (lens == NULL)
95 		goto out;
96 
97 	for (result = dns_rdatasetiter_first(iter);
98 	     result == ISC_R_SUCCESS;
99 	     result = dns_rdatasetiter_next(iter))
100 	{
101 		result = ISC_R_NOMEMORY;
102 		dns_rdataset_init(&set);
103 		dns_rdatasetiter_current(iter, &set);
104 
105 		if (set.type != dns_rdatatype_rrsig) {
106 			dns_rdataset_disassociate(&set);
107 			continue;
108 		}
109 
110 		count = dns_rdataset_count(&set);
111 		if (used + count > size) {
112 			/* copy & reallocate */
113 			oldsize = size;
114 			oldrdatas = rdatas;
115 			oldlens = lens;
116 			rdatas = NULL;
117 			lens = NULL;
118 
119 			size *= 2;
120 
121 			rdatas = isc_mem_get(mctx, size * sizeof(*rdatas));
122 			if (rdatas == NULL)
123 				goto out;
124 			lens = isc_mem_get(mctx, size * sizeof(*lens));
125 			if (lens == NULL)
126 				goto out;
127 			memmove(rdatas, oldrdatas, used * sizeof(*rdatas));
128 			memmove(lens, oldlens, used * sizeof(*lens));
129 			isc_mem_put(mctx, oldrdatas,
130 				    oldsize * sizeof(*oldrdatas));
131 			isc_mem_put(mctx, oldlens, oldsize * sizeof(*oldlens));
132 			oldrdatas = NULL;
133 			oldlens = NULL;
134 		}
135 		if (set.ttl < ttl)
136 			ttl = set.ttl;
137 		if (set.trust != dns_trust_secure)
138 			flags &= (~LWRDATA_VALIDATED);
139 		result = fill_array(&used, &set, size, rdatas, lens);
140 		dns_rdataset_disassociate(&set);
141 		if (result != ISC_R_SUCCESS)
142 			goto out;
143 	}
144 	if (result == ISC_R_NOMORE)
145 		result = ISC_R_SUCCESS;
146 	if (result != ISC_R_SUCCESS)
147 		goto out;
148 	dns_rdatasetiter_destroy(&iter);
149 
150 	/*
151 	 * If necessary, shrink and copy the arrays.
152 	 */
153 	if (size != used) {
154 		result = ISC_R_NOMEMORY;
155 		newrdatas = isc_mem_get(mctx, used * sizeof(*rdatas));
156 		if (newrdatas == NULL)
157 			goto out;
158 		newlens = isc_mem_get(mctx, used * sizeof(*lens));
159 		if (newlens == NULL)
160 			goto out;
161 		memmove(newrdatas, rdatas, used * sizeof(*rdatas));
162 		memmove(newlens, lens, used * sizeof(*lens));
163 		isc_mem_put(mctx, rdatas, size * sizeof(*rdatas));
164 		isc_mem_put(mctx, lens, size * sizeof(*lens));
165 		grbn->rdatas = newrdatas;
166 		grbn->rdatalen = newlens;
167 	} else {
168 		grbn->rdatas = rdatas;
169 		grbn->rdatalen = lens;
170 	}
171 	grbn->nrdatas = used;
172 	grbn->ttl = ttl;
173 	grbn->flags = flags;
174 	return (ISC_R_SUCCESS);
175 
176  out:
177 	dns_rdatasetiter_destroy(&iter);
178 	if (rdatas != NULL)
179 		isc_mem_put(mctx, rdatas, size * sizeof(*rdatas));
180 	if (lens != NULL)
181 		isc_mem_put(mctx, lens, size * sizeof(*lens));
182 	if (oldrdatas != NULL)
183 		isc_mem_put(mctx, oldrdatas, oldsize * sizeof(*oldrdatas));
184 	if (oldlens != NULL)
185 		isc_mem_put(mctx, oldlens, oldsize * sizeof(*oldlens));
186 	if (newrdatas != NULL)
187 		isc_mem_put(mctx, newrdatas, used * sizeof(*newrdatas));
188 	return (result);
189 }
190 
191 static void
lookup_done(isc_task_t * task,isc_event_t * event)192 lookup_done(isc_task_t *task, isc_event_t *event) {
193 	ns_lwdclient_t *client;
194 	ns_lwdclientmgr_t *cm;
195 	dns_lookupevent_t *levent;
196 	lwres_buffer_t lwb;
197 	dns_name_t *name;
198 	dns_rdataset_t *rdataset;
199 	dns_rdataset_t *sigrdataset;
200 	isc_result_t result;
201 	lwres_result_t lwresult;
202 	isc_region_t r;
203 	isc_buffer_t b;
204 	lwres_grbnresponse_t *grbn;
205 	int i;
206 
207 	REQUIRE(event != NULL);
208 
209 	UNUSED(task);
210 
211 	lwb.base = NULL;
212 	client = event->ev_arg;
213 	cm = client->clientmgr;
214 	INSIST(client->lookup == (dns_lookup_t *)event->ev_sender);
215 
216 	levent = (dns_lookupevent_t *)event;
217 	grbn = &client->grbn;
218 
219 	ns_lwdclient_log(50, "lookup event result = %s",
220 			 isc_result_totext(levent->result));
221 
222 	result = levent->result;
223 	if (result != ISC_R_SUCCESS) {
224 		dns_lookup_destroy(&client->lookup);
225 		isc_event_free(&event);
226 		levent = NULL;
227 
228 		switch (result) {
229 		case DNS_R_NXDOMAIN:
230 		case DNS_R_NCACHENXDOMAIN:
231 			result = ns_lwsearchctx_next(&client->searchctx);
232 			if (result != ISC_R_SUCCESS)
233 				lwresult = LWRES_R_NOTFOUND;
234 			else {
235 				start_lookup(client);
236 				return;
237 			}
238 			break;
239 		case DNS_R_NXRRSET:
240 		case DNS_R_NCACHENXRRSET:
241 			lwresult = LWRES_R_TYPENOTFOUND;
242 			break;
243 		default:
244 			lwresult = LWRES_R_FAILURE;
245 		}
246 		ns_lwdclient_errorpktsend(client, lwresult);
247 		return;
248 	}
249 
250 	name = levent->name;
251 	b = client->recv_buffer;
252 
253 	grbn->flags = 0;
254 
255 	grbn->nrdatas = 0;
256 	grbn->rdatas = NULL;
257 	grbn->rdatalen = NULL;
258 
259 	grbn->nsigs = 0;
260 	grbn->sigs = NULL;
261 	grbn->siglen = NULL;
262 
263 	result = dns_name_totext(name, ISC_TRUE, &client->recv_buffer);
264 	if (result != ISC_R_SUCCESS)
265 		goto out;
266 	grbn->realname = (char *)isc_buffer_used(&b);
267 	grbn->realnamelen = isc_buffer_usedlength(&client->recv_buffer) -
268 			    isc_buffer_usedlength(&b);
269 	ns_lwdclient_log(50, "found name '%.*s'", grbn->realnamelen,
270 			 grbn->realname);
271 
272 	grbn->rdclass = cm->view->rdclass;
273 	grbn->rdtype = client->rdtype;
274 
275 	rdataset = levent->rdataset;
276 	if (rdataset != NULL) {
277 		/* The normal case */
278 		grbn->nrdatas = dns_rdataset_count(rdataset);
279 		grbn->rdatas = isc_mem_get(cm->mctx, grbn->nrdatas *
280 					   sizeof(unsigned char *));
281 		if (grbn->rdatas == NULL)
282 			goto out;
283 		grbn->rdatalen = isc_mem_get(cm->mctx, grbn->nrdatas *
284 					     sizeof(lwres_uint16_t));
285 		if (grbn->rdatalen == NULL)
286 			goto out;
287 
288 		i = 0;
289 		result = fill_array(&i, rdataset, grbn->nrdatas, grbn->rdatas,
290 				    grbn->rdatalen);
291 		if (result != ISC_R_SUCCESS)
292 			goto out;
293 		INSIST(i == grbn->nrdatas);
294 		grbn->ttl = rdataset->ttl;
295 		if (rdataset->trust == dns_trust_secure)
296 			grbn->flags |= LWRDATA_VALIDATED;
297 	} else {
298 		/* The SIG query case */
299 		result = iterate_node(grbn, levent->db, levent->node,
300 				      cm->mctx);
301 		if (result != ISC_R_SUCCESS)
302 			goto out;
303 	}
304 	ns_lwdclient_log(50, "filled in %d rdata%s", grbn->nrdatas,
305 			 (grbn->nrdatas == 1) ? "" : "s");
306 
307 	sigrdataset = levent->sigrdataset;
308 	if (sigrdataset != NULL) {
309 		grbn->nsigs = dns_rdataset_count(sigrdataset);
310 		grbn->sigs = isc_mem_get(cm->mctx, grbn->nsigs *
311 					 sizeof(unsigned char *));
312 		if (grbn->sigs == NULL)
313 			goto out;
314 		grbn->siglen = isc_mem_get(cm->mctx, grbn->nsigs *
315 					   sizeof(lwres_uint16_t));
316 		if (grbn->siglen == NULL)
317 			goto out;
318 
319 		i = 0;
320 		result = fill_array(&i, sigrdataset, grbn->nsigs, grbn->sigs,
321 				    grbn->siglen);
322 		if (result != ISC_R_SUCCESS)
323 			goto out;
324 		INSIST(i == grbn->nsigs);
325 		ns_lwdclient_log(50, "filled in %d signature%s", grbn->nsigs,
326 				 (grbn->nsigs == 1) ? "" : "s");
327 	}
328 
329 	/*
330 	 * Render the packet.
331 	 */
332 	client->pkt.recvlength = LWRES_RECVLENGTH;
333 	client->pkt.authtype = 0; /* XXXMLG */
334 	client->pkt.authlength = 0;
335 	client->pkt.result = LWRES_R_SUCCESS;
336 
337 	lwresult = lwres_grbnresponse_render(cm->lwctx,
338 					     grbn, &client->pkt, &lwb);
339 	if (lwresult != LWRES_R_SUCCESS)
340 		goto out;
341 
342 	isc_mem_put(cm->mctx, grbn->rdatas,
343 		    grbn->nrdatas * sizeof(unsigned char *));
344 	isc_mem_put(cm->mctx, grbn->rdatalen,
345 		    grbn->nrdatas * sizeof(lwres_uint16_t));
346 
347 	if (grbn->sigs != NULL)
348 		isc_mem_put(cm->mctx, grbn->sigs,
349 			    grbn->nsigs * sizeof(unsigned char *));
350 	if (grbn->siglen != NULL)
351 		isc_mem_put(cm->mctx, grbn->siglen,
352 			    grbn->nsigs * sizeof(lwres_uint16_t));
353 
354 	r.base = lwb.base;
355 	r.length = lwb.used;
356 	client->sendbuf = r.base;
357 	client->sendlength = r.length;
358 	result = ns_lwdclient_sendreply(client, &r);
359 	if (result != ISC_R_SUCCESS)
360 		goto out2;
361 
362 	NS_LWDCLIENT_SETSEND(client);
363 
364 	dns_lookup_destroy(&client->lookup);
365 	isc_event_free(&event);
366 
367 	return;
368 
369  out:
370 	if (grbn->rdatas != NULL)
371 		isc_mem_put(cm->mctx, grbn->rdatas,
372 			    grbn->nrdatas * sizeof(unsigned char *));
373 	if (grbn->rdatalen != NULL)
374 		isc_mem_put(cm->mctx, grbn->rdatalen,
375 			    grbn->nrdatas * sizeof(lwres_uint16_t));
376 
377 	if (grbn->sigs != NULL)
378 		isc_mem_put(cm->mctx, grbn->sigs,
379 			    grbn->nsigs * sizeof(unsigned char *));
380 	if (grbn->siglen != NULL)
381 		isc_mem_put(cm->mctx, grbn->siglen,
382 			    grbn->nsigs * sizeof(lwres_uint16_t));
383  out2:
384 	if (client->lookup != NULL)
385 		dns_lookup_destroy(&client->lookup);
386 	if (lwb.base != NULL)
387 		lwres_context_freemem(cm->lwctx, lwb.base, lwb.length);
388 
389 	isc_event_free(&event);
390 
391 	ns_lwdclient_log(50, "error constructing getrrsetbyname response");
392 	ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
393 }
394 
395 static void
start_lookup(ns_lwdclient_t * client)396 start_lookup(ns_lwdclient_t *client) {
397 	isc_result_t result;
398 	ns_lwdclientmgr_t *cm;
399 	dns_fixedname_t absname;
400 
401 	cm = client->clientmgr;
402 
403 	INSIST(client->lookup == NULL);
404 
405 	dns_fixedname_init(&absname);
406 
407 	/*
408 	 * Perform search across all search domains until success
409 	 * is returned. Return in case of failure.
410 	 */
411 	while (ns_lwsearchctx_current(&client->searchctx,
412 			dns_fixedname_name(&absname)) != ISC_R_SUCCESS) {
413 		if (ns_lwsearchctx_next(&client->searchctx) != ISC_R_SUCCESS) {
414 			ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
415 			return;
416 		}
417 	}
418 
419 	result = dns_lookup_create(cm->mctx,
420 				   dns_fixedname_name(&absname),
421 				   client->rdtype, cm->view,
422 				   client->options, cm->task, lookup_done,
423 				   client, &client->lookup);
424 	if (result != ISC_R_SUCCESS) {
425 		ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
426 		return;
427 	}
428 }
429 
430 static void
init_grbn(ns_lwdclient_t * client)431 init_grbn(ns_lwdclient_t *client) {
432 	client->grbn.rdclass = 0;
433 	client->grbn.rdtype = 0;
434 	client->grbn.ttl = 0;
435 	client->grbn.nrdatas = 0;
436 	client->grbn.realname = NULL;
437 	client->grbn.realnamelen = 0;
438 	client->grbn.rdatas = 0;
439 	client->grbn.rdatalen = 0;
440 	client->grbn.base = NULL;
441 	client->grbn.baselen = 0;
442 	isc_buffer_init(&client->recv_buffer, client->buffer, LWRES_RECVLENGTH);
443 }
444 
445 void
ns_lwdclient_processgrbn(ns_lwdclient_t * client,lwres_buffer_t * b)446 ns_lwdclient_processgrbn(ns_lwdclient_t *client, lwres_buffer_t *b) {
447 	lwres_grbnrequest_t *req;
448 	isc_result_t result;
449 	ns_lwdclientmgr_t *cm;
450 	isc_buffer_t namebuf;
451 
452 	REQUIRE(NS_LWDCLIENT_ISRECVDONE(client));
453 	INSIST(client->byaddr == NULL);
454 
455 	cm = client->clientmgr;
456 	req = NULL;
457 
458 	result = lwres_grbnrequest_parse(cm->lwctx,
459 					 b, &client->pkt, &req);
460 	if (result != LWRES_R_SUCCESS)
461 		goto out;
462 	if (req->name == NULL)
463 		goto out;
464 
465 	client->options = 0;
466 	if (req->rdclass != cm->view->rdclass)
467 		goto out;
468 
469 	if (req->rdclass == dns_rdataclass_any ||
470 	    req->rdtype == dns_rdatatype_any)
471 		goto out;
472 
473 	client->rdtype = req->rdtype;
474 
475 	isc_buffer_init(&namebuf, req->name, req->namelen);
476 	isc_buffer_add(&namebuf, req->namelen);
477 
478 	dns_fixedname_init(&client->query_name);
479 	result = dns_name_fromtext(dns_fixedname_name(&client->query_name),
480 				   &namebuf, NULL, 0, NULL);
481 	if (result != ISC_R_SUCCESS)
482 		goto out;
483 	ns_lwsearchctx_init(&client->searchctx,
484 			    cm->listener->manager->search,
485 			    dns_fixedname_name(&client->query_name),
486 			    cm->listener->manager->ndots);
487 	ns_lwsearchctx_first(&client->searchctx);
488 
489 	ns_lwdclient_log(50, "client %p looking for type %d",
490 			 client, client->rdtype);
491 
492 	/*
493 	 * We no longer need to keep this around.
494 	 */
495 	lwres_grbnrequest_free(cm->lwctx, &req);
496 
497 	/*
498 	 * Initialize the real name and alias arrays in the reply we're
499 	 * going to build up.
500 	 */
501 	init_grbn(client);
502 
503 	/*
504 	 * Start the find.
505 	 */
506 	start_lookup(client);
507 
508 	return;
509 
510 	/*
511 	 * We're screwed.  Return an error packet to our caller.
512 	 */
513  out:
514 	if (req != NULL)
515 		lwres_grbnrequest_free(cm->lwctx, &req);
516 
517 	ns_lwdclient_errorpktsend(client, LWRES_R_FAILURE);
518 }
519