xref: /freebsd/contrib/unbound/dnstap/dnstap.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
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 	fstrm_res res;
125 	struct dt_env *env;
126 	struct fstrm_iothr_options *fopt;
127 	struct fstrm_unix_writer_options *fuwopt;
128 	struct fstrm_writer *fw;
129 	struct fstrm_writer_options *fwopt;
130 
131 	verbose(VERB_OPS, "attempting to connect to dnstap socket %s",
132 		socket_path);
133 	log_assert(socket_path != NULL);
134 	log_assert(num_workers > 0);
135 
136 	env = (struct dt_env *) calloc(1, sizeof(struct dt_env));
137 	if (!env)
138 		return NULL;
139 
140 	fwopt = fstrm_writer_options_init();
141 	res = fstrm_writer_options_add_content_type(fwopt,
142 		DNSTAP_CONTENT_TYPE, sizeof(DNSTAP_CONTENT_TYPE) - 1);
143 	log_assert(res == fstrm_res_success);
144 
145 	fuwopt = fstrm_unix_writer_options_init();
146 	fstrm_unix_writer_options_set_socket_path(fuwopt, socket_path);
147 
148 	fw = fstrm_unix_writer_init(fuwopt, fwopt);
149 	log_assert(fw != NULL);
150 
151 	fopt = fstrm_iothr_options_init();
152 	fstrm_iothr_options_set_num_input_queues(fopt, num_workers);
153 	env->iothr = fstrm_iothr_init(fopt, &fw);
154 	if (env->iothr == NULL) {
155 		verbose(VERB_DETAIL, "dt_create: fstrm_iothr_init() failed");
156 		fstrm_writer_destroy(&fw);
157 		free(env);
158 		env = NULL;
159 	}
160 	fstrm_iothr_options_destroy(&fopt);
161 	fstrm_unix_writer_options_destroy(&fuwopt);
162 	fstrm_writer_options_destroy(&fwopt);
163 
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)
250 {
251 	env->ioq = fstrm_iothr_get_input_queue(env->iothr);
252 	if (env->ioq == NULL)
253 		return 0;
254 	return 1;
255 }
256 
257 void
258 dt_delete(struct dt_env *env)
259 {
260 	if (!env)
261 		return;
262 	verbose(VERB_OPS, "closing dnstap socket");
263 	fstrm_iothr_destroy(&env->iothr);
264 	free(env->identity);
265 	free(env->version);
266 	free(env);
267 }
268 
269 static void
270 dt_fill_timeval(const struct timeval *tv,
271 		uint64_t *time_sec, protobuf_c_boolean *has_time_sec,
272 		uint32_t *time_nsec, protobuf_c_boolean *has_time_nsec)
273 {
274 #ifndef S_SPLINT_S
275 	*time_sec = tv->tv_sec;
276 	*time_nsec = tv->tv_usec * 1000;
277 #endif
278 	*has_time_sec = 1;
279 	*has_time_nsec = 1;
280 }
281 
282 static void
283 dt_fill_buffer(sldns_buffer *b, ProtobufCBinaryData *p, protobuf_c_boolean *has)
284 {
285 	log_assert(b != NULL);
286 	p->len = sldns_buffer_limit(b);
287 	p->data = sldns_buffer_begin(b);
288 	*has = 1;
289 }
290 
291 static void
292 dt_msg_fill_net(struct dt_msg *dm,
293 		struct sockaddr_storage *ss,
294 		enum comm_point_type cptype,
295 		ProtobufCBinaryData *addr, protobuf_c_boolean *has_addr,
296 		uint32_t *port, protobuf_c_boolean *has_port)
297 {
298 	log_assert(ss->ss_family == AF_INET6 || ss->ss_family == AF_INET);
299 	if (ss->ss_family == AF_INET6) {
300 		struct sockaddr_in6 *s = (struct sockaddr_in6 *) ss;
301 
302 		/* socket_family */
303 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET6;
304 		dm->m.has_socket_family = 1;
305 
306 		/* addr: query_address or response_address */
307 		addr->data = s->sin6_addr.s6_addr;
308 		addr->len = 16; /* IPv6 */
309 		*has_addr = 1;
310 
311 		/* port: query_port or response_port */
312 		*port = ntohs(s->sin6_port);
313 		*has_port = 1;
314 	} else if (ss->ss_family == AF_INET) {
315 		struct sockaddr_in *s = (struct sockaddr_in *) ss;
316 
317 		/* socket_family */
318 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET;
319 		dm->m.has_socket_family = 1;
320 
321 		/* addr: query_address or response_address */
322 		addr->data = (uint8_t *) &s->sin_addr.s_addr;
323 		addr->len = 4; /* IPv4 */
324 		*has_addr = 1;
325 
326 		/* port: query_port or response_port */
327 		*port = ntohs(s->sin_port);
328 		*has_port = 1;
329 	}
330 
331 	log_assert(cptype == comm_udp || cptype == comm_tcp);
332 	if (cptype == comm_udp) {
333 		/* socket_protocol */
334 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__UDP;
335 		dm->m.has_socket_protocol = 1;
336 	} else if (cptype == comm_tcp) {
337 		/* socket_protocol */
338 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__TCP;
339 		dm->m.has_socket_protocol = 1;
340 	}
341 }
342 
343 void
344 dt_msg_send_client_query(struct dt_env *env,
345 			 struct sockaddr_storage *qsock,
346 			 enum comm_point_type cptype,
347 			 sldns_buffer *qmsg)
348 {
349 	struct dt_msg dm;
350 	struct timeval qtime;
351 
352 	gettimeofday(&qtime, NULL);
353 
354 	/* type */
355 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_QUERY);
356 
357 	/* query_time */
358 	dt_fill_timeval(&qtime,
359 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
360 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
361 
362 	/* query_message */
363 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
364 
365 	/* socket_family, socket_protocol, query_address, query_port */
366 	log_assert(cptype == comm_udp || cptype == comm_tcp);
367 	dt_msg_fill_net(&dm, qsock, cptype,
368 			&dm.m.query_address, &dm.m.has_query_address,
369 			&dm.m.query_port, &dm.m.has_query_port);
370 
371 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
372 		dt_send(env, dm.buf, dm.len_buf);
373 }
374 
375 void
376 dt_msg_send_client_response(struct dt_env *env,
377 			    struct sockaddr_storage *qsock,
378 			    enum comm_point_type cptype,
379 			    sldns_buffer *rmsg)
380 {
381 	struct dt_msg dm;
382 	struct timeval rtime;
383 
384 	gettimeofday(&rtime, NULL);
385 
386 	/* type */
387 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_RESPONSE);
388 
389 	/* response_time */
390 	dt_fill_timeval(&rtime,
391 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
392 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
393 
394 	/* response_message */
395 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
396 
397 	/* socket_family, socket_protocol, query_address, query_port */
398 	log_assert(cptype == comm_udp || cptype == comm_tcp);
399 	dt_msg_fill_net(&dm, qsock, cptype,
400 			&dm.m.query_address, &dm.m.has_query_address,
401 			&dm.m.query_port, &dm.m.has_query_port);
402 
403 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
404 		dt_send(env, dm.buf, dm.len_buf);
405 }
406 
407 void
408 dt_msg_send_outside_query(struct dt_env *env,
409 			  struct sockaddr_storage *rsock,
410 			  enum comm_point_type cptype,
411 			  uint8_t *zone, size_t zone_len,
412 			  sldns_buffer *qmsg)
413 {
414 	struct dt_msg dm;
415 	struct timeval qtime;
416 	uint16_t qflags;
417 
418 	gettimeofday(&qtime, NULL);
419 	qflags = sldns_buffer_read_u16_at(qmsg, 2);
420 
421 	/* type */
422 	if (qflags & BIT_RD) {
423 		if (!env->log_forwarder_query_messages)
424 			return;
425 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_QUERY);
426 	} else {
427 		if (!env->log_resolver_query_messages)
428 			return;
429 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_QUERY);
430 	}
431 
432 	/* query_zone */
433 	dm.m.query_zone.data = zone;
434 	dm.m.query_zone.len = zone_len;
435 	dm.m.has_query_zone = 1;
436 
437 	/* query_time_sec, query_time_nsec */
438 	dt_fill_timeval(&qtime,
439 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
440 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
441 
442 	/* query_message */
443 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
444 
445 	/* socket_family, socket_protocol, response_address, response_port */
446 	log_assert(cptype == comm_udp || cptype == comm_tcp);
447 	dt_msg_fill_net(&dm, rsock, cptype,
448 			&dm.m.response_address, &dm.m.has_response_address,
449 			&dm.m.response_port, &dm.m.has_response_port);
450 
451 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
452 		dt_send(env, dm.buf, dm.len_buf);
453 }
454 
455 void
456 dt_msg_send_outside_response(struct dt_env *env,
457 			     struct sockaddr_storage *rsock,
458 			     enum comm_point_type cptype,
459 			     uint8_t *zone, size_t zone_len,
460 			     uint8_t *qbuf, size_t qbuf_len,
461 			     const struct timeval *qtime,
462 			     const struct timeval *rtime,
463 			     sldns_buffer *rmsg)
464 {
465 	struct dt_msg dm;
466 	uint16_t qflags;
467 
468 	log_assert(qbuf_len >= sizeof(qflags));
469 	memcpy(&qflags, qbuf, sizeof(qflags));
470 	qflags = ntohs(qflags);
471 
472 	/* type */
473 	if (qflags & BIT_RD) {
474 		if (!env->log_forwarder_response_messages)
475 			return;
476 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_RESPONSE);
477 	} else {
478 		if (!env->log_resolver_response_messages)
479 			return;
480 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_RESPONSE);
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 	/* response_time_sec, response_time_nsec */
494 	dt_fill_timeval(rtime,
495 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
496 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
497 
498 	/* response_message */
499 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
500 
501 	/* socket_family, socket_protocol, response_address, response_port */
502 	log_assert(cptype == comm_udp || cptype == comm_tcp);
503 	dt_msg_fill_net(&dm, rsock, cptype,
504 			&dm.m.response_address, &dm.m.has_response_address,
505 			&dm.m.response_port, &dm.m.has_response_port);
506 
507 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
508 		dt_send(env, dm.buf, dm.len_buf);
509 }
510 
511 #endif /* USE_DNSTAP */
512