xref: /freebsd/contrib/unbound/dnstap/dnstap.c (revision 148a8da8)
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 #include "sldns/sbuffer.h"
43 #include "util/config_file.h"
44 #include "util/net_help.h"
45 #include "util/netevent.h"
46 #include "util/log.h"
47 
48 #include <fstrm.h>
49 #include <protobuf-c/protobuf-c.h>
50 
51 #include "dnstap/dnstap.h"
52 #include "dnstap/dnstap.pb-c.h"
53 
54 #define DNSTAP_CONTENT_TYPE		"protobuf:dnstap.Dnstap"
55 #define DNSTAP_INITIAL_BUF_SIZE		256
56 
57 struct dt_msg {
58 	void		*buf;
59 	size_t		len_buf;
60 	Dnstap__Dnstap	d;
61 	Dnstap__Message	m;
62 };
63 
64 static int
65 dt_pack(const Dnstap__Dnstap *d, void **buf, size_t *sz)
66 {
67 	ProtobufCBufferSimple sbuf;
68 
69 	memset(&sbuf, 0, sizeof(sbuf));
70 	sbuf.base.append = protobuf_c_buffer_simple_append;
71 	sbuf.len = 0;
72 	sbuf.alloced = DNSTAP_INITIAL_BUF_SIZE;
73 	sbuf.data = malloc(sbuf.alloced);
74 	if (sbuf.data == NULL)
75 		return 0;
76 	sbuf.must_free_data = 1;
77 
78 	*sz = dnstap__dnstap__pack_to_buffer(d, (ProtobufCBuffer *) &sbuf);
79 	if (sbuf.data == NULL)
80 		return 0;
81 	*buf = sbuf.data;
82 
83 	return 1;
84 }
85 
86 static void
87 dt_send(const struct dt_env *env, void *buf, size_t len_buf)
88 {
89 	fstrm_res res;
90 	if (!buf)
91 		return;
92 	res = fstrm_iothr_submit(env->iothr, env->ioq, buf, len_buf,
93 				 fstrm_free_wrapper, NULL);
94 	if (res != fstrm_res_success)
95 		free(buf);
96 }
97 
98 static void
99 dt_msg_init(const struct dt_env *env,
100 	    struct dt_msg *dm,
101 	    Dnstap__Message__Type mtype)
102 {
103 	memset(dm, 0, sizeof(*dm));
104 	dm->d.base.descriptor = &dnstap__dnstap__descriptor;
105 	dm->m.base.descriptor = &dnstap__message__descriptor;
106 	dm->d.type = DNSTAP__DNSTAP__TYPE__MESSAGE;
107 	dm->d.message = &dm->m;
108 	dm->m.type = mtype;
109 	if (env->identity != NULL) {
110 		dm->d.identity.data = (uint8_t *) env->identity;
111 		dm->d.identity.len = (size_t) env->len_identity;
112 		dm->d.has_identity = 1;
113 	}
114 	if (env->version != NULL) {
115 		dm->d.version.data = (uint8_t *) env->version;
116 		dm->d.version.len = (size_t) env->len_version;
117 		dm->d.has_version = 1;
118 	}
119 }
120 
121 struct dt_env *
122 dt_create(const char *socket_path, unsigned num_workers)
123 {
124 #ifdef UNBOUND_DEBUG
125 	fstrm_res res;
126 #endif
127 	struct dt_env *env;
128 	struct fstrm_iothr_options *fopt;
129 	struct fstrm_unix_writer_options *fuwopt;
130 	struct fstrm_writer *fw;
131 	struct fstrm_writer_options *fwopt;
132 
133 	verbose(VERB_OPS, "attempting to connect to dnstap socket %s",
134 		socket_path);
135 	log_assert(socket_path != NULL);
136 	log_assert(num_workers > 0);
137 
138 	env = (struct dt_env *) calloc(1, sizeof(struct dt_env));
139 	if (!env)
140 		return NULL;
141 
142 	fwopt = fstrm_writer_options_init();
143 #ifdef UNBOUND_DEBUG
144 	res =
145 #else
146 	(void)
147 #endif
148 	    fstrm_writer_options_add_content_type(fwopt,
149 		DNSTAP_CONTENT_TYPE, sizeof(DNSTAP_CONTENT_TYPE) - 1);
150 	log_assert(res == fstrm_res_success);
151 
152 	fuwopt = fstrm_unix_writer_options_init();
153 	fstrm_unix_writer_options_set_socket_path(fuwopt, socket_path);
154 
155 	fw = fstrm_unix_writer_init(fuwopt, fwopt);
156 	log_assert(fw != NULL);
157 
158 	fopt = fstrm_iothr_options_init();
159 	fstrm_iothr_options_set_num_input_queues(fopt, num_workers);
160 	env->iothr = fstrm_iothr_init(fopt, &fw);
161 	if (env->iothr == NULL) {
162 		verbose(VERB_DETAIL, "dt_create: fstrm_iothr_init() failed");
163 		fstrm_writer_destroy(&fw);
164 		free(env);
165 		env = NULL;
166 	}
167 	fstrm_iothr_options_destroy(&fopt);
168 	fstrm_unix_writer_options_destroy(&fuwopt);
169 	fstrm_writer_options_destroy(&fwopt);
170 
171 	return env;
172 }
173 
174 static void
175 dt_apply_identity(struct dt_env *env, struct config_file *cfg)
176 {
177 	char buf[MAXHOSTNAMELEN+1];
178 	if (!cfg->dnstap_send_identity)
179 		return;
180 	free(env->identity);
181 	if (cfg->dnstap_identity == NULL || cfg->dnstap_identity[0] == 0) {
182 		if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
183 			buf[MAXHOSTNAMELEN] = 0;
184 			env->identity = strdup(buf);
185 		} else {
186 			fatal_exit("dt_apply_identity: gethostname() failed");
187 		}
188 	} else {
189 		env->identity = strdup(cfg->dnstap_identity);
190 	}
191 	if (env->identity == NULL)
192 		fatal_exit("dt_apply_identity: strdup() failed");
193 	env->len_identity = (unsigned int)strlen(env->identity);
194 	verbose(VERB_OPS, "dnstap identity field set to \"%s\"",
195 		env->identity);
196 }
197 
198 static void
199 dt_apply_version(struct dt_env *env, struct config_file *cfg)
200 {
201 	if (!cfg->dnstap_send_version)
202 		return;
203 	free(env->version);
204 	if (cfg->dnstap_version == NULL || cfg->dnstap_version[0] == 0)
205 		env->version = strdup(PACKAGE_STRING);
206 	else
207 		env->version = strdup(cfg->dnstap_version);
208 	if (env->version == NULL)
209 		fatal_exit("dt_apply_version: strdup() failed");
210 	env->len_version = (unsigned int)strlen(env->version);
211 	verbose(VERB_OPS, "dnstap version field set to \"%s\"",
212 		env->version);
213 }
214 
215 void
216 dt_apply_cfg(struct dt_env *env, struct config_file *cfg)
217 {
218 	if (!cfg->dnstap)
219 		return;
220 
221 	dt_apply_identity(env, cfg);
222 	dt_apply_version(env, cfg);
223 	if ((env->log_resolver_query_messages = (unsigned int)
224 	     cfg->dnstap_log_resolver_query_messages))
225 	{
226 		verbose(VERB_OPS, "dnstap Message/RESOLVER_QUERY enabled");
227 	}
228 	if ((env->log_resolver_response_messages = (unsigned int)
229 	     cfg->dnstap_log_resolver_response_messages))
230 	{
231 		verbose(VERB_OPS, "dnstap Message/RESOLVER_RESPONSE enabled");
232 	}
233 	if ((env->log_client_query_messages = (unsigned int)
234 	     cfg->dnstap_log_client_query_messages))
235 	{
236 		verbose(VERB_OPS, "dnstap Message/CLIENT_QUERY enabled");
237 	}
238 	if ((env->log_client_response_messages = (unsigned int)
239 	     cfg->dnstap_log_client_response_messages))
240 	{
241 		verbose(VERB_OPS, "dnstap Message/CLIENT_RESPONSE enabled");
242 	}
243 	if ((env->log_forwarder_query_messages = (unsigned int)
244 	     cfg->dnstap_log_forwarder_query_messages))
245 	{
246 		verbose(VERB_OPS, "dnstap Message/FORWARDER_QUERY enabled");
247 	}
248 	if ((env->log_forwarder_response_messages = (unsigned int)
249 	     cfg->dnstap_log_forwarder_response_messages))
250 	{
251 		verbose(VERB_OPS, "dnstap Message/FORWARDER_RESPONSE enabled");
252 	}
253 }
254 
255 int
256 dt_init(struct dt_env *env)
257 {
258 	env->ioq = fstrm_iothr_get_input_queue(env->iothr);
259 	if (env->ioq == NULL)
260 		return 0;
261 	return 1;
262 }
263 
264 void
265 dt_delete(struct dt_env *env)
266 {
267 	if (!env)
268 		return;
269 	verbose(VERB_OPS, "closing dnstap socket");
270 	fstrm_iothr_destroy(&env->iothr);
271 	free(env->identity);
272 	free(env->version);
273 	free(env);
274 }
275 
276 static void
277 dt_fill_timeval(const struct timeval *tv,
278 		uint64_t *time_sec, protobuf_c_boolean *has_time_sec,
279 		uint32_t *time_nsec, protobuf_c_boolean *has_time_nsec)
280 {
281 #ifndef S_SPLINT_S
282 	*time_sec = tv->tv_sec;
283 	*time_nsec = tv->tv_usec * 1000;
284 #endif
285 	*has_time_sec = 1;
286 	*has_time_nsec = 1;
287 }
288 
289 static void
290 dt_fill_buffer(sldns_buffer *b, ProtobufCBinaryData *p, protobuf_c_boolean *has)
291 {
292 	log_assert(b != NULL);
293 	p->len = sldns_buffer_limit(b);
294 	p->data = sldns_buffer_begin(b);
295 	*has = 1;
296 }
297 
298 static void
299 dt_msg_fill_net(struct dt_msg *dm,
300 		struct sockaddr_storage *ss,
301 		enum comm_point_type cptype,
302 		ProtobufCBinaryData *addr, protobuf_c_boolean *has_addr,
303 		uint32_t *port, protobuf_c_boolean *has_port)
304 {
305 	log_assert(ss->ss_family == AF_INET6 || ss->ss_family == AF_INET);
306 	if (ss->ss_family == AF_INET6) {
307 		struct sockaddr_in6 *s = (struct sockaddr_in6 *) ss;
308 
309 		/* socket_family */
310 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET6;
311 		dm->m.has_socket_family = 1;
312 
313 		/* addr: query_address or response_address */
314 		addr->data = s->sin6_addr.s6_addr;
315 		addr->len = 16; /* IPv6 */
316 		*has_addr = 1;
317 
318 		/* port: query_port or response_port */
319 		*port = ntohs(s->sin6_port);
320 		*has_port = 1;
321 	} else if (ss->ss_family == AF_INET) {
322 		struct sockaddr_in *s = (struct sockaddr_in *) ss;
323 
324 		/* socket_family */
325 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET;
326 		dm->m.has_socket_family = 1;
327 
328 		/* addr: query_address or response_address */
329 		addr->data = (uint8_t *) &s->sin_addr.s_addr;
330 		addr->len = 4; /* IPv4 */
331 		*has_addr = 1;
332 
333 		/* port: query_port or response_port */
334 		*port = ntohs(s->sin_port);
335 		*has_port = 1;
336 	}
337 
338 	log_assert(cptype == comm_udp || cptype == comm_tcp);
339 	if (cptype == comm_udp) {
340 		/* socket_protocol */
341 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__UDP;
342 		dm->m.has_socket_protocol = 1;
343 	} else if (cptype == comm_tcp) {
344 		/* socket_protocol */
345 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__TCP;
346 		dm->m.has_socket_protocol = 1;
347 	}
348 }
349 
350 void
351 dt_msg_send_client_query(struct dt_env *env,
352 			 struct sockaddr_storage *qsock,
353 			 enum comm_point_type cptype,
354 			 sldns_buffer *qmsg)
355 {
356 	struct dt_msg dm;
357 	struct timeval qtime;
358 
359 	gettimeofday(&qtime, NULL);
360 
361 	/* type */
362 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_QUERY);
363 
364 	/* query_time */
365 	dt_fill_timeval(&qtime,
366 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
367 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
368 
369 	/* query_message */
370 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
371 
372 	/* socket_family, socket_protocol, query_address, query_port */
373 	log_assert(cptype == comm_udp || cptype == comm_tcp);
374 	dt_msg_fill_net(&dm, qsock, cptype,
375 			&dm.m.query_address, &dm.m.has_query_address,
376 			&dm.m.query_port, &dm.m.has_query_port);
377 
378 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
379 		dt_send(env, dm.buf, dm.len_buf);
380 }
381 
382 void
383 dt_msg_send_client_response(struct dt_env *env,
384 			    struct sockaddr_storage *qsock,
385 			    enum comm_point_type cptype,
386 			    sldns_buffer *rmsg)
387 {
388 	struct dt_msg dm;
389 	struct timeval rtime;
390 
391 	gettimeofday(&rtime, NULL);
392 
393 	/* type */
394 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_RESPONSE);
395 
396 	/* response_time */
397 	dt_fill_timeval(&rtime,
398 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
399 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
400 
401 	/* response_message */
402 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
403 
404 	/* socket_family, socket_protocol, query_address, query_port */
405 	log_assert(cptype == comm_udp || cptype == comm_tcp);
406 	dt_msg_fill_net(&dm, qsock, cptype,
407 			&dm.m.query_address, &dm.m.has_query_address,
408 			&dm.m.query_port, &dm.m.has_query_port);
409 
410 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
411 		dt_send(env, dm.buf, dm.len_buf);
412 }
413 
414 void
415 dt_msg_send_outside_query(struct dt_env *env,
416 			  struct sockaddr_storage *rsock,
417 			  enum comm_point_type cptype,
418 			  uint8_t *zone, size_t zone_len,
419 			  sldns_buffer *qmsg)
420 {
421 	struct dt_msg dm;
422 	struct timeval qtime;
423 	uint16_t qflags;
424 
425 	gettimeofday(&qtime, NULL);
426 	qflags = sldns_buffer_read_u16_at(qmsg, 2);
427 
428 	/* type */
429 	if (qflags & BIT_RD) {
430 		if (!env->log_forwarder_query_messages)
431 			return;
432 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_QUERY);
433 	} else {
434 		if (!env->log_resolver_query_messages)
435 			return;
436 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_QUERY);
437 	}
438 
439 	/* query_zone */
440 	dm.m.query_zone.data = zone;
441 	dm.m.query_zone.len = zone_len;
442 	dm.m.has_query_zone = 1;
443 
444 	/* query_time_sec, query_time_nsec */
445 	dt_fill_timeval(&qtime,
446 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
447 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
448 
449 	/* query_message */
450 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
451 
452 	/* socket_family, socket_protocol, response_address, response_port */
453 	log_assert(cptype == comm_udp || cptype == comm_tcp);
454 	dt_msg_fill_net(&dm, rsock, cptype,
455 			&dm.m.response_address, &dm.m.has_response_address,
456 			&dm.m.response_port, &dm.m.has_response_port);
457 
458 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
459 		dt_send(env, dm.buf, dm.len_buf);
460 }
461 
462 void
463 dt_msg_send_outside_response(struct dt_env *env,
464 			     struct sockaddr_storage *rsock,
465 			     enum comm_point_type cptype,
466 			     uint8_t *zone, size_t zone_len,
467 			     uint8_t *qbuf, size_t qbuf_len,
468 			     const struct timeval *qtime,
469 			     const struct timeval *rtime,
470 			     sldns_buffer *rmsg)
471 {
472 	struct dt_msg dm;
473 	uint16_t qflags;
474 
475 	log_assert(qbuf_len >= sizeof(qflags));
476 	memcpy(&qflags, qbuf, sizeof(qflags));
477 	qflags = ntohs(qflags);
478 
479 	/* type */
480 	if (qflags & BIT_RD) {
481 		if (!env->log_forwarder_response_messages)
482 			return;
483 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_RESPONSE);
484 	} else {
485 		if (!env->log_resolver_response_messages)
486 			return;
487 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_RESPONSE);
488 	}
489 
490 	/* query_zone */
491 	dm.m.query_zone.data = zone;
492 	dm.m.query_zone.len = zone_len;
493 	dm.m.has_query_zone = 1;
494 
495 	/* query_time_sec, query_time_nsec */
496 	dt_fill_timeval(qtime,
497 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
498 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
499 
500 	/* response_time_sec, response_time_nsec */
501 	dt_fill_timeval(rtime,
502 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
503 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
504 
505 	/* response_message */
506 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
507 
508 	/* socket_family, socket_protocol, response_address, response_port */
509 	log_assert(cptype == comm_udp || cptype == comm_tcp);
510 	dt_msg_fill_net(&dm, rsock, cptype,
511 			&dm.m.response_address, &dm.m.has_response_address,
512 			&dm.m.response_port, &dm.m.has_response_port);
513 
514 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
515 		dt_send(env, dm.buf, dm.len_buf);
516 }
517 
518 #endif /* USE_DNSTAP */
519