xref: /freebsd/contrib/unbound/dnstap/dnstap.c (revision bce7ee9d412b6410e6d799c4a417617cbb148e09)
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 = fname_after_chroot(cfg->dnstap_socket_path, cfg, 1);
138 		if(!p) {
139 			log_err("malloc failure");
140 			return NULL;
141 		}
142 		verbose(VERB_OPS, "attempting to connect to dnstap socket %s",
143 			p);
144 		check_socket_file(p);
145 		free(p);
146 	}
147 
148 	env = (struct dt_env *) calloc(1, sizeof(struct dt_env));
149 	if (!env)
150 		return NULL;
151 
152 	env->dtio = dt_io_thread_create();
153 	if(!env->dtio) {
154 		log_err("malloc failure");
155 		free(env);
156 		return NULL;
157 	}
158 	if(!dt_io_thread_apply_cfg(env->dtio, cfg)) {
159 		dt_io_thread_delete(env->dtio);
160 		free(env);
161 		return NULL;
162 	}
163 	dt_apply_cfg(env, cfg);
164 	return env;
165 }
166 
167 static void
168 dt_apply_identity(struct dt_env *env, struct config_file *cfg)
169 {
170 	char buf[MAXHOSTNAMELEN+1];
171 	if (!cfg->dnstap_send_identity)
172 		return;
173 	free(env->identity);
174 	if (cfg->dnstap_identity == NULL || cfg->dnstap_identity[0] == 0) {
175 		if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
176 			buf[MAXHOSTNAMELEN] = 0;
177 			env->identity = strdup(buf);
178 		} else {
179 			fatal_exit("dt_apply_identity: gethostname() failed");
180 		}
181 	} else {
182 		env->identity = strdup(cfg->dnstap_identity);
183 	}
184 	if (env->identity == NULL)
185 		fatal_exit("dt_apply_identity: strdup() failed");
186 	env->len_identity = (unsigned int)strlen(env->identity);
187 	verbose(VERB_OPS, "dnstap identity field set to \"%s\"",
188 		env->identity);
189 }
190 
191 static void
192 dt_apply_version(struct dt_env *env, struct config_file *cfg)
193 {
194 	if (!cfg->dnstap_send_version)
195 		return;
196 	free(env->version);
197 	if (cfg->dnstap_version == NULL || cfg->dnstap_version[0] == 0)
198 		env->version = strdup(PACKAGE_STRING);
199 	else
200 		env->version = strdup(cfg->dnstap_version);
201 	if (env->version == NULL)
202 		fatal_exit("dt_apply_version: strdup() failed");
203 	env->len_version = (unsigned int)strlen(env->version);
204 	verbose(VERB_OPS, "dnstap version field set to \"%s\"",
205 		env->version);
206 }
207 
208 void
209 dt_apply_cfg(struct dt_env *env, struct config_file *cfg)
210 {
211 	if (!cfg->dnstap)
212 		return;
213 
214 	dt_apply_identity(env, cfg);
215 	dt_apply_version(env, cfg);
216 	if ((env->log_resolver_query_messages = (unsigned int)
217 	     cfg->dnstap_log_resolver_query_messages))
218 	{
219 		verbose(VERB_OPS, "dnstap Message/RESOLVER_QUERY enabled");
220 	}
221 	if ((env->log_resolver_response_messages = (unsigned int)
222 	     cfg->dnstap_log_resolver_response_messages))
223 	{
224 		verbose(VERB_OPS, "dnstap Message/RESOLVER_RESPONSE enabled");
225 	}
226 	if ((env->log_client_query_messages = (unsigned int)
227 	     cfg->dnstap_log_client_query_messages))
228 	{
229 		verbose(VERB_OPS, "dnstap Message/CLIENT_QUERY enabled");
230 	}
231 	if ((env->log_client_response_messages = (unsigned int)
232 	     cfg->dnstap_log_client_response_messages))
233 	{
234 		verbose(VERB_OPS, "dnstap Message/CLIENT_RESPONSE enabled");
235 	}
236 	if ((env->log_forwarder_query_messages = (unsigned int)
237 	     cfg->dnstap_log_forwarder_query_messages))
238 	{
239 		verbose(VERB_OPS, "dnstap Message/FORWARDER_QUERY enabled");
240 	}
241 	if ((env->log_forwarder_response_messages = (unsigned int)
242 	     cfg->dnstap_log_forwarder_response_messages))
243 	{
244 		verbose(VERB_OPS, "dnstap Message/FORWARDER_RESPONSE enabled");
245 	}
246 }
247 
248 int
249 dt_init(struct dt_env *env, struct comm_base* base)
250 {
251 	env->msgqueue = dt_msg_queue_create(base);
252 	if(!env->msgqueue) {
253 		log_err("malloc failure");
254 		return 0;
255 	}
256 	if(!dt_io_thread_register_queue(env->dtio, env->msgqueue)) {
257 		log_err("malloc failure");
258 		dt_msg_queue_delete(env->msgqueue);
259 		env->msgqueue = NULL;
260 		return 0;
261 	}
262 	return 1;
263 }
264 
265 void
266 dt_deinit(struct dt_env* env)
267 {
268 	dt_io_thread_unregister_queue(env->dtio, env->msgqueue);
269 	dt_msg_queue_delete(env->msgqueue);
270 }
271 
272 void
273 dt_delete(struct dt_env *env)
274 {
275 	if (!env)
276 		return;
277 	dt_io_thread_delete(env->dtio);
278 	free(env->identity);
279 	free(env->version);
280 	free(env);
281 }
282 
283 static void
284 dt_fill_timeval(const struct timeval *tv,
285 		uint64_t *time_sec, protobuf_c_boolean *has_time_sec,
286 		uint32_t *time_nsec, protobuf_c_boolean *has_time_nsec)
287 {
288 #ifndef S_SPLINT_S
289 	*time_sec = tv->tv_sec;
290 	*time_nsec = tv->tv_usec * 1000;
291 #endif
292 	*has_time_sec = 1;
293 	*has_time_nsec = 1;
294 }
295 
296 static void
297 dt_fill_buffer(sldns_buffer *b, ProtobufCBinaryData *p, protobuf_c_boolean *has)
298 {
299 	log_assert(b != NULL);
300 	p->len = sldns_buffer_limit(b);
301 	p->data = sldns_buffer_begin(b);
302 	*has = 1;
303 }
304 
305 static void
306 dt_msg_fill_net(struct dt_msg *dm,
307 		struct sockaddr_storage *ss,
308 		enum comm_point_type cptype,
309 		ProtobufCBinaryData *addr, protobuf_c_boolean *has_addr,
310 		uint32_t *port, protobuf_c_boolean *has_port)
311 {
312 	log_assert(ss->ss_family == AF_INET6 || ss->ss_family == AF_INET);
313 	if (ss->ss_family == AF_INET6) {
314 		struct sockaddr_in6 *s = (struct sockaddr_in6 *) ss;
315 
316 		/* socket_family */
317 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET6;
318 		dm->m.has_socket_family = 1;
319 
320 		/* addr: query_address or response_address */
321 		addr->data = s->sin6_addr.s6_addr;
322 		addr->len = 16; /* IPv6 */
323 		*has_addr = 1;
324 
325 		/* port: query_port or response_port */
326 		*port = ntohs(s->sin6_port);
327 		*has_port = 1;
328 	} else if (ss->ss_family == AF_INET) {
329 		struct sockaddr_in *s = (struct sockaddr_in *) ss;
330 
331 		/* socket_family */
332 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET;
333 		dm->m.has_socket_family = 1;
334 
335 		/* addr: query_address or response_address */
336 		addr->data = (uint8_t *) &s->sin_addr.s_addr;
337 		addr->len = 4; /* IPv4 */
338 		*has_addr = 1;
339 
340 		/* port: query_port or response_port */
341 		*port = ntohs(s->sin_port);
342 		*has_port = 1;
343 	}
344 
345 	log_assert(cptype == comm_udp || cptype == comm_tcp);
346 	if (cptype == comm_udp) {
347 		/* socket_protocol */
348 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__UDP;
349 		dm->m.has_socket_protocol = 1;
350 	} else if (cptype == comm_tcp) {
351 		/* socket_protocol */
352 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__TCP;
353 		dm->m.has_socket_protocol = 1;
354 	}
355 }
356 
357 void
358 dt_msg_send_client_query(struct dt_env *env,
359 			 struct sockaddr_storage *qsock,
360 			 enum comm_point_type cptype,
361 			 sldns_buffer *qmsg)
362 {
363 	struct dt_msg dm;
364 	struct timeval qtime;
365 
366 	gettimeofday(&qtime, NULL);
367 
368 	/* type */
369 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_QUERY);
370 
371 	/* query_time */
372 	dt_fill_timeval(&qtime,
373 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
374 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
375 
376 	/* query_message */
377 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
378 
379 	/* socket_family, socket_protocol, query_address, query_port */
380 	log_assert(cptype == comm_udp || cptype == comm_tcp);
381 	dt_msg_fill_net(&dm, qsock, cptype,
382 			&dm.m.query_address, &dm.m.has_query_address,
383 			&dm.m.query_port, &dm.m.has_query_port);
384 
385 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
386 		dt_send(env, dm.buf, dm.len_buf);
387 }
388 
389 void
390 dt_msg_send_client_response(struct dt_env *env,
391 			    struct sockaddr_storage *qsock,
392 			    enum comm_point_type cptype,
393 			    sldns_buffer *rmsg)
394 {
395 	struct dt_msg dm;
396 	struct timeval rtime;
397 
398 	gettimeofday(&rtime, NULL);
399 
400 	/* type */
401 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_RESPONSE);
402 
403 	/* response_time */
404 	dt_fill_timeval(&rtime,
405 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
406 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
407 
408 	/* response_message */
409 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
410 
411 	/* socket_family, socket_protocol, query_address, query_port */
412 	log_assert(cptype == comm_udp || cptype == comm_tcp);
413 	dt_msg_fill_net(&dm, qsock, cptype,
414 			&dm.m.query_address, &dm.m.has_query_address,
415 			&dm.m.query_port, &dm.m.has_query_port);
416 
417 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
418 		dt_send(env, dm.buf, dm.len_buf);
419 }
420 
421 void
422 dt_msg_send_outside_query(struct dt_env *env,
423 			  struct sockaddr_storage *rsock,
424 			  enum comm_point_type cptype,
425 			  uint8_t *zone, size_t zone_len,
426 			  sldns_buffer *qmsg)
427 {
428 	struct dt_msg dm;
429 	struct timeval qtime;
430 	uint16_t qflags;
431 
432 	gettimeofday(&qtime, NULL);
433 	qflags = sldns_buffer_read_u16_at(qmsg, 2);
434 
435 	/* type */
436 	if (qflags & BIT_RD) {
437 		if (!env->log_forwarder_query_messages)
438 			return;
439 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_QUERY);
440 	} else {
441 		if (!env->log_resolver_query_messages)
442 			return;
443 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_QUERY);
444 	}
445 
446 	/* query_zone */
447 	dm.m.query_zone.data = zone;
448 	dm.m.query_zone.len = zone_len;
449 	dm.m.has_query_zone = 1;
450 
451 	/* query_time_sec, query_time_nsec */
452 	dt_fill_timeval(&qtime,
453 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
454 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
455 
456 	/* query_message */
457 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
458 
459 	/* socket_family, socket_protocol, response_address, response_port */
460 	log_assert(cptype == comm_udp || cptype == comm_tcp);
461 	dt_msg_fill_net(&dm, rsock, cptype,
462 			&dm.m.response_address, &dm.m.has_response_address,
463 			&dm.m.response_port, &dm.m.has_response_port);
464 
465 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
466 		dt_send(env, dm.buf, dm.len_buf);
467 }
468 
469 void
470 dt_msg_send_outside_response(struct dt_env *env,
471 			     struct sockaddr_storage *rsock,
472 			     enum comm_point_type cptype,
473 			     uint8_t *zone, size_t zone_len,
474 			     uint8_t *qbuf, size_t qbuf_len,
475 			     const struct timeval *qtime,
476 			     const struct timeval *rtime,
477 			     sldns_buffer *rmsg)
478 {
479 	struct dt_msg dm;
480 	uint16_t qflags;
481 
482 	log_assert(qbuf_len >= sizeof(qflags));
483 	memcpy(&qflags, qbuf, sizeof(qflags));
484 	qflags = ntohs(qflags);
485 
486 	/* type */
487 	if (qflags & BIT_RD) {
488 		if (!env->log_forwarder_response_messages)
489 			return;
490 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_RESPONSE);
491 	} else {
492 		if (!env->log_resolver_response_messages)
493 			return;
494 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_RESPONSE);
495 	}
496 
497 	/* query_zone */
498 	dm.m.query_zone.data = zone;
499 	dm.m.query_zone.len = zone_len;
500 	dm.m.has_query_zone = 1;
501 
502 	/* query_time_sec, query_time_nsec */
503 	dt_fill_timeval(qtime,
504 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
505 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
506 
507 	/* response_time_sec, response_time_nsec */
508 	dt_fill_timeval(rtime,
509 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
510 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
511 
512 	/* response_message */
513 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
514 
515 	/* socket_family, socket_protocol, response_address, response_port */
516 	log_assert(cptype == comm_udp || cptype == comm_tcp);
517 	dt_msg_fill_net(&dm, rsock, cptype,
518 			&dm.m.response_address, &dm.m.has_response_address,
519 			&dm.m.response_port, &dm.m.has_response_port);
520 
521 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
522 		dt_send(env, dm.buf, dm.len_buf);
523 }
524 
525 #endif /* USE_DNSTAP */
526