xref: /freebsd/contrib/unbound/dnstap/dnstap.c (revision 8881d206f4e68b564c2c5f50fc717086fc3e827a)
1 /* dnstap support for Unbound */
2 
3 /*
4  * Copyright (c) 2013-2014, Farsight Security, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  * notice, this list of conditions and the following disclaimer in the
16  * documentation and/or other materials provided with the distribution.
17  *
18  * 3. Neither the name of the copyright holder nor the names of its
19  * contributors may be used to endorse or promote products derived from
20  * this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
26  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
29  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
32  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include "dnstap/dnstap_config.h"
36 
37 #ifdef USE_DNSTAP
38 
39 #include "config.h"
40 #include <string.h>
41 #include <sys/time.h>
42 #ifdef HAVE_SYS_STAT_H
43 #include <sys/stat.h>
44 #endif
45 #include <errno.h>
46 #include "sldns/sbuffer.h"
47 #include "util/config_file.h"
48 #include "util/net_help.h"
49 #include "util/netevent.h"
50 #include "util/log.h"
51 
52 #include <protobuf-c/protobuf-c.h>
53 
54 #include "dnstap/dnstap.h"
55 #include "dnstap/dtstream.h"
56 #include "dnstap/dnstap.pb-c.h"
57 
58 #define DNSTAP_INITIAL_BUF_SIZE		256
59 
60 struct dt_msg {
61 	void		*buf;
62 	size_t		len_buf;
63 	Dnstap__Dnstap	d;
64 	Dnstap__Message	m;
65 };
66 
67 static int
68 dt_pack(const Dnstap__Dnstap *d, void **buf, size_t *sz)
69 {
70 	ProtobufCBufferSimple sbuf;
71 
72 	memset(&sbuf, 0, sizeof(sbuf));
73 	sbuf.base.append = protobuf_c_buffer_simple_append;
74 	sbuf.len = 0;
75 	sbuf.alloced = DNSTAP_INITIAL_BUF_SIZE;
76 	sbuf.data = malloc(sbuf.alloced);
77 	if (sbuf.data == NULL)
78 		return 0;
79 	sbuf.must_free_data = 1;
80 
81 	*sz = dnstap__dnstap__pack_to_buffer(d, (ProtobufCBuffer *) &sbuf);
82 	if (sbuf.data == NULL)
83 		return 0;
84 	*buf = sbuf.data;
85 
86 	return 1;
87 }
88 
89 static void
90 dt_send(const struct dt_env *env, void *buf, size_t len_buf)
91 {
92 	dt_msg_queue_submit(env->msgqueue, buf, len_buf);
93 }
94 
95 static void
96 dt_msg_init(const struct dt_env *env,
97 	    struct dt_msg *dm,
98 	    Dnstap__Message__Type mtype)
99 {
100 	memset(dm, 0, sizeof(*dm));
101 	dm->d.base.descriptor = &dnstap__dnstap__descriptor;
102 	dm->m.base.descriptor = &dnstap__message__descriptor;
103 	dm->d.type = DNSTAP__DNSTAP__TYPE__MESSAGE;
104 	dm->d.message = &dm->m;
105 	dm->m.type = mtype;
106 	if (env->identity != NULL) {
107 		dm->d.identity.data = (uint8_t *) env->identity;
108 		dm->d.identity.len = (size_t) env->len_identity;
109 		dm->d.has_identity = 1;
110 	}
111 	if (env->version != NULL) {
112 		dm->d.version.data = (uint8_t *) env->version;
113 		dm->d.version.len = (size_t) env->len_version;
114 		dm->d.has_version = 1;
115 	}
116 }
117 
118 /* check that the socket file can be opened and exists, print error if not */
119 static void
120 check_socket_file(const char* socket_path)
121 {
122 	struct stat statbuf;
123 	memset(&statbuf, 0, sizeof(statbuf));
124 	if(stat(socket_path, &statbuf) < 0) {
125 		log_warn("could not open dnstap-socket-path: %s, %s",
126 			socket_path, strerror(errno));
127 	}
128 }
129 
130 struct dt_env *
131 dt_create(struct config_file* cfg)
132 {
133 	struct dt_env *env;
134 
135 	if(cfg->dnstap && cfg->dnstap_socket_path && cfg->dnstap_socket_path[0] &&
136 		(cfg->dnstap_ip==NULL || cfg->dnstap_ip[0]==0)) {
137 		char* p = cfg->dnstap_socket_path;
138 		if(cfg->chrootdir && cfg->chrootdir[0] && strncmp(p,
139 			cfg->chrootdir, strlen(cfg->chrootdir)) == 0)
140 			p += strlen(cfg->chrootdir);
141 		verbose(VERB_OPS, "attempting to connect to dnstap socket %s",
142 			p);
143 		check_socket_file(p);
144 	}
145 
146 	env = (struct dt_env *) calloc(1, sizeof(struct dt_env));
147 	if (!env)
148 		return NULL;
149 
150 	env->dtio = dt_io_thread_create();
151 	if(!env->dtio) {
152 		log_err("malloc failure");
153 		free(env);
154 		return NULL;
155 	}
156 	if(!dt_io_thread_apply_cfg(env->dtio, cfg)) {
157 		dt_io_thread_delete(env->dtio);
158 		free(env);
159 		return NULL;
160 	}
161 	dt_apply_cfg(env, cfg);
162 	return env;
163 }
164 
165 static void
166 dt_apply_identity(struct dt_env *env, struct config_file *cfg)
167 {
168 	char buf[MAXHOSTNAMELEN+1];
169 	if (!cfg->dnstap_send_identity)
170 		return;
171 	free(env->identity);
172 	if (cfg->dnstap_identity == NULL || cfg->dnstap_identity[0] == 0) {
173 		if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
174 			buf[MAXHOSTNAMELEN] = 0;
175 			env->identity = strdup(buf);
176 		} else {
177 			fatal_exit("dt_apply_identity: gethostname() failed");
178 		}
179 	} else {
180 		env->identity = strdup(cfg->dnstap_identity);
181 	}
182 	if (env->identity == NULL)
183 		fatal_exit("dt_apply_identity: strdup() failed");
184 	env->len_identity = (unsigned int)strlen(env->identity);
185 	verbose(VERB_OPS, "dnstap identity field set to \"%s\"",
186 		env->identity);
187 }
188 
189 static void
190 dt_apply_version(struct dt_env *env, struct config_file *cfg)
191 {
192 	if (!cfg->dnstap_send_version)
193 		return;
194 	free(env->version);
195 	if (cfg->dnstap_version == NULL || cfg->dnstap_version[0] == 0)
196 		env->version = strdup(PACKAGE_STRING);
197 	else
198 		env->version = strdup(cfg->dnstap_version);
199 	if (env->version == NULL)
200 		fatal_exit("dt_apply_version: strdup() failed");
201 	env->len_version = (unsigned int)strlen(env->version);
202 	verbose(VERB_OPS, "dnstap version field set to \"%s\"",
203 		env->version);
204 }
205 
206 void
207 dt_apply_cfg(struct dt_env *env, struct config_file *cfg)
208 {
209 	if (!cfg->dnstap)
210 		return;
211 
212 	dt_apply_identity(env, cfg);
213 	dt_apply_version(env, cfg);
214 	if ((env->log_resolver_query_messages = (unsigned int)
215 	     cfg->dnstap_log_resolver_query_messages))
216 	{
217 		verbose(VERB_OPS, "dnstap Message/RESOLVER_QUERY enabled");
218 	}
219 	if ((env->log_resolver_response_messages = (unsigned int)
220 	     cfg->dnstap_log_resolver_response_messages))
221 	{
222 		verbose(VERB_OPS, "dnstap Message/RESOLVER_RESPONSE enabled");
223 	}
224 	if ((env->log_client_query_messages = (unsigned int)
225 	     cfg->dnstap_log_client_query_messages))
226 	{
227 		verbose(VERB_OPS, "dnstap Message/CLIENT_QUERY enabled");
228 	}
229 	if ((env->log_client_response_messages = (unsigned int)
230 	     cfg->dnstap_log_client_response_messages))
231 	{
232 		verbose(VERB_OPS, "dnstap Message/CLIENT_RESPONSE enabled");
233 	}
234 	if ((env->log_forwarder_query_messages = (unsigned int)
235 	     cfg->dnstap_log_forwarder_query_messages))
236 	{
237 		verbose(VERB_OPS, "dnstap Message/FORWARDER_QUERY enabled");
238 	}
239 	if ((env->log_forwarder_response_messages = (unsigned int)
240 	     cfg->dnstap_log_forwarder_response_messages))
241 	{
242 		verbose(VERB_OPS, "dnstap Message/FORWARDER_RESPONSE enabled");
243 	}
244 }
245 
246 int
247 dt_init(struct dt_env *env, struct comm_base* base)
248 {
249 	env->msgqueue = dt_msg_queue_create(base);
250 	if(!env->msgqueue) {
251 		log_err("malloc failure");
252 		return 0;
253 	}
254 	if(!dt_io_thread_register_queue(env->dtio, env->msgqueue)) {
255 		log_err("malloc failure");
256 		dt_msg_queue_delete(env->msgqueue);
257 		env->msgqueue = NULL;
258 		return 0;
259 	}
260 	return 1;
261 }
262 
263 void
264 dt_deinit(struct dt_env* env)
265 {
266 	dt_io_thread_unregister_queue(env->dtio, env->msgqueue);
267 	dt_msg_queue_delete(env->msgqueue);
268 }
269 
270 void
271 dt_delete(struct dt_env *env)
272 {
273 	if (!env)
274 		return;
275 	dt_io_thread_delete(env->dtio);
276 	free(env->identity);
277 	free(env->version);
278 	free(env);
279 }
280 
281 static void
282 dt_fill_timeval(const struct timeval *tv,
283 		uint64_t *time_sec, protobuf_c_boolean *has_time_sec,
284 		uint32_t *time_nsec, protobuf_c_boolean *has_time_nsec)
285 {
286 #ifndef S_SPLINT_S
287 	*time_sec = tv->tv_sec;
288 	*time_nsec = tv->tv_usec * 1000;
289 #endif
290 	*has_time_sec = 1;
291 	*has_time_nsec = 1;
292 }
293 
294 static void
295 dt_fill_buffer(sldns_buffer *b, ProtobufCBinaryData *p, protobuf_c_boolean *has)
296 {
297 	log_assert(b != NULL);
298 	p->len = sldns_buffer_limit(b);
299 	p->data = sldns_buffer_begin(b);
300 	*has = 1;
301 }
302 
303 static void
304 dt_msg_fill_net(struct dt_msg *dm,
305 		struct sockaddr_storage *qs,
306 		struct sockaddr_storage *rs,
307 		enum comm_point_type cptype,
308 		ProtobufCBinaryData *qaddr, protobuf_c_boolean *has_qaddr,
309 		uint32_t *qport, protobuf_c_boolean *has_qport,
310 		ProtobufCBinaryData *raddr, protobuf_c_boolean *has_raddr,
311 		uint32_t *rport, protobuf_c_boolean *has_rport)
312 {
313 	log_assert(qs->ss_family == AF_INET6 || qs->ss_family == AF_INET);
314 	if (qs->ss_family == AF_INET6) {
315 		struct sockaddr_in6 *q = (struct sockaddr_in6 *) qs;
316 
317 		/* socket_family */
318 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET6;
319 		dm->m.has_socket_family = 1;
320 
321 		/* addr: query_address or response_address */
322 		qaddr->data = q->sin6_addr.s6_addr;
323 		qaddr->len = 16; /* IPv6 */
324 		*has_qaddr = 1;
325 
326 		/* port: query_port or response_port */
327 		*qport = ntohs(q->sin6_port);
328 		*has_qport = 1;
329 	} else if (qs->ss_family == AF_INET) {
330 		struct sockaddr_in *q = (struct sockaddr_in *) qs;
331 
332 		/* socket_family */
333 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET;
334 		dm->m.has_socket_family = 1;
335 
336 		/* addr: query_address or response_address */
337 		qaddr->data = (uint8_t *) &q->sin_addr.s_addr;
338 		qaddr->len = 4; /* IPv4 */
339 		*has_qaddr = 1;
340 
341 		/* port: query_port or response_port */
342 		*qport = ntohs(q->sin_port);
343 		*has_qport = 1;
344 	}
345 
346 	/*
347 	 * This block is to fill second set of fields in DNSTAP-message defined as request_/response_ names.
348 	 * Additional responsive structure is: struct sockaddr_storage *rs
349 	 */
350         if (rs && rs->ss_family == AF_INET6) {
351                 struct sockaddr_in6 *r = (struct sockaddr_in6 *) rs;
352 
353                 /* addr: query_address or response_address */
354                 raddr->data = r->sin6_addr.s6_addr;
355                 raddr->len = 16; /* IPv6 */
356                 *has_raddr = 1;
357 
358                 /* port: query_port or response_port */
359                 *rport = ntohs(r->sin6_port);
360                 *has_rport = 1;
361         } else if (rs && rs->ss_family == AF_INET) {
362                 struct sockaddr_in *r = (struct sockaddr_in *) rs;
363 
364                 /* addr: query_address or response_address */
365                 raddr->data = (uint8_t *) &r->sin_addr.s_addr;
366                 raddr->len = 4; /* IPv4 */
367                 *has_raddr = 1;
368 
369                 /* port: query_port or response_port */
370                 *rport = ntohs(r->sin_port);
371                 *has_rport = 1;
372         }
373 
374 	log_assert(cptype == comm_udp || cptype == comm_tcp);
375 	if (cptype == comm_udp) {
376 		/* socket_protocol */
377 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__UDP;
378 		dm->m.has_socket_protocol = 1;
379 	} else if (cptype == comm_tcp) {
380 		/* socket_protocol */
381 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__TCP;
382 		dm->m.has_socket_protocol = 1;
383 	}
384 }
385 
386 void
387 dt_msg_send_client_query(struct dt_env *env,
388 			 struct sockaddr_storage *qsock,
389 			 struct sockaddr_storage *rsock,
390 			 enum comm_point_type cptype,
391 			 sldns_buffer *qmsg)
392 {
393 	struct dt_msg dm;
394 	struct timeval qtime;
395 
396 	gettimeofday(&qtime, NULL);
397 
398 	/* type */
399 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_QUERY);
400 
401 	/* query_time */
402 	dt_fill_timeval(&qtime,
403 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
404 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
405 
406 	/* query_message */
407 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
408 
409 	/* socket_family, socket_protocol, query_address, query_port, response_address, response_port */
410 	log_assert(cptype == comm_udp || cptype == comm_tcp);
411 	dt_msg_fill_net(&dm, qsock, rsock, cptype,
412 			&dm.m.query_address, &dm.m.has_query_address,
413 			&dm.m.query_port, &dm.m.has_query_port,
414 			&dm.m.response_address, &dm.m.has_response_address,
415 			&dm.m.response_port, &dm.m.has_response_port);
416 
417 
418 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
419 		dt_send(env, dm.buf, dm.len_buf);
420 }
421 
422 void
423 dt_msg_send_client_response(struct dt_env *env,
424 			    struct sockaddr_storage *qsock,
425 			    struct sockaddr_storage *rsock,
426 			    enum comm_point_type cptype,
427 			    sldns_buffer *rmsg)
428 {
429 	struct dt_msg dm;
430 	struct timeval rtime;
431 
432 	gettimeofday(&rtime, NULL);
433 
434 	/* type */
435 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_RESPONSE);
436 
437 	/* response_time */
438 	dt_fill_timeval(&rtime,
439 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
440 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
441 
442 	/* response_message */
443 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
444 
445 	/* socket_family, socket_protocol, query_address, query_port, response_address, response_port */
446 	log_assert(cptype == comm_udp || cptype == comm_tcp);
447 	dt_msg_fill_net(&dm, qsock, rsock, cptype,
448 			&dm.m.query_address, &dm.m.has_query_address,
449 			&dm.m.query_port, &dm.m.has_query_port,
450                         &dm.m.response_address, &dm.m.has_response_address,
451                         &dm.m.response_port, &dm.m.has_response_port);
452 
453 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
454 		dt_send(env, dm.buf, dm.len_buf);
455 }
456 
457 void
458 dt_msg_send_outside_query(struct dt_env *env,
459 			  struct sockaddr_storage *rsock,
460 			  struct sockaddr_storage *qsock,
461 			  enum comm_point_type cptype,
462 			  uint8_t *zone, size_t zone_len,
463 			  sldns_buffer *qmsg)
464 {
465 	struct dt_msg dm;
466 	struct timeval qtime;
467 	uint16_t qflags;
468 
469 	gettimeofday(&qtime, NULL);
470 	qflags = sldns_buffer_read_u16_at(qmsg, 2);
471 
472 	/* type */
473 	if (qflags & BIT_RD) {
474 		if (!env->log_forwarder_query_messages)
475 			return;
476 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_QUERY);
477 	} else {
478 		if (!env->log_resolver_query_messages)
479 			return;
480 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_QUERY);
481 	}
482 
483 	/* query_zone */
484 	dm.m.query_zone.data = zone;
485 	dm.m.query_zone.len = zone_len;
486 	dm.m.has_query_zone = 1;
487 
488 	/* query_time_sec, query_time_nsec */
489 	dt_fill_timeval(&qtime,
490 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
491 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
492 
493 	/* query_message */
494 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
495 
496 	/* socket_family, socket_protocol, response_address, response_port, query_address, query_port */
497 	log_assert(cptype == comm_udp || cptype == comm_tcp);
498 	dt_msg_fill_net(&dm, rsock, qsock, cptype,
499 			&dm.m.response_address, &dm.m.has_response_address,
500 			&dm.m.response_port, &dm.m.has_response_port,
501 			&dm.m.query_address, &dm.m.has_query_address,
502 			&dm.m.query_port, &dm.m.has_query_port);
503 
504 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
505 		dt_send(env, dm.buf, dm.len_buf);
506 }
507 
508 void
509 dt_msg_send_outside_response(struct dt_env *env,
510 	struct sockaddr_storage *rsock,
511 	struct sockaddr_storage *qsock,
512 	enum comm_point_type cptype,
513 	uint8_t *zone, size_t zone_len,
514 	uint8_t *qbuf, size_t qbuf_len,
515 	const struct timeval *qtime,
516 	const struct timeval *rtime,
517 	sldns_buffer *rmsg)
518 {
519 	struct dt_msg dm;
520 	uint16_t qflags;
521 
522 	(void)qbuf_len; log_assert(qbuf_len >= sizeof(qflags));
523 	memcpy(&qflags, qbuf, sizeof(qflags));
524 	qflags = ntohs(qflags);
525 
526 	/* type */
527 	if (qflags & BIT_RD) {
528 		if (!env->log_forwarder_response_messages)
529 			return;
530 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_RESPONSE);
531 	} else {
532 		if (!env->log_resolver_response_messages)
533 			return;
534 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_RESPONSE);
535 	}
536 
537 	/* query_zone */
538 	dm.m.query_zone.data = zone;
539 	dm.m.query_zone.len = zone_len;
540 	dm.m.has_query_zone = 1;
541 
542 	/* query_time_sec, query_time_nsec */
543 	dt_fill_timeval(qtime,
544 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
545 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
546 
547 	/* response_time_sec, response_time_nsec */
548 	dt_fill_timeval(rtime,
549 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
550 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
551 
552 	/* response_message */
553 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
554 
555 	/* socket_family, socket_protocol, response_address, response_port, query_address, query_port */
556 	log_assert(cptype == comm_udp || cptype == comm_tcp);
557 	dt_msg_fill_net(&dm, rsock, qsock, cptype,
558 			&dm.m.response_address, &dm.m.has_response_address,
559 			&dm.m.response_port, &dm.m.has_response_port,
560 			&dm.m.query_address, &dm.m.has_query_address,
561 			&dm.m.query_port, &dm.m.has_query_port);
562 
563 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
564 		dt_send(env, dm.buf, dm.len_buf);
565 }
566 
567 #endif /* USE_DNSTAP */
568