xref: /freebsd/contrib/unbound/dnstap/dnstap.c (revision a831d7d1c538b93ffec095657d9a6e6e778db195)
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 "ldns/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, "opening dnstap socket %s", socket_path);
132 	log_assert(socket_path != NULL);
133 	log_assert(num_workers > 0);
134 
135 	env = (struct dt_env *) calloc(1, sizeof(struct dt_env));
136 	if (!env)
137 		return NULL;
138 
139 	fwopt = fstrm_writer_options_init();
140 	res = fstrm_writer_options_add_content_type(fwopt,
141 		DNSTAP_CONTENT_TYPE, sizeof(DNSTAP_CONTENT_TYPE) - 1);
142 	log_assert(res == fstrm_res_success);
143 
144 	fuwopt = fstrm_unix_writer_options_init();
145 	fstrm_unix_writer_options_set_socket_path(fuwopt, socket_path);
146 
147 	fw = fstrm_unix_writer_init(fuwopt, fwopt);
148 	log_assert(fw != NULL);
149 
150 	fopt = fstrm_iothr_options_init();
151 	fstrm_iothr_options_set_num_input_queues(fopt, num_workers);
152 	env->iothr = fstrm_iothr_init(fopt, &fw);
153 	if (env->iothr == NULL) {
154 		verbose(VERB_DETAIL, "dt_create: fstrm_iothr_init() failed");
155 		fstrm_writer_destroy(&fw);
156 		free(env);
157 		env = NULL;
158 	}
159 	fstrm_iothr_options_destroy(&fopt);
160 	fstrm_unix_writer_options_destroy(&fuwopt);
161 	fstrm_writer_options_destroy(&fwopt);
162 
163 	return env;
164 }
165 
166 static void
167 dt_apply_identity(struct dt_env *env, struct config_file *cfg)
168 {
169 	char buf[MAXHOSTNAMELEN+1];
170 	if (!cfg->dnstap_send_identity)
171 		return;
172 	free(env->identity);
173 	if (cfg->dnstap_identity == NULL || cfg->dnstap_identity[0] == 0) {
174 		if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
175 			buf[MAXHOSTNAMELEN] = 0;
176 			env->identity = strdup(buf);
177 		} else {
178 			fatal_exit("dt_apply_identity: gethostname() failed");
179 		}
180 	} else {
181 		env->identity = strdup(cfg->dnstap_identity);
182 	}
183 	if (env->identity == NULL)
184 		fatal_exit("dt_apply_identity: strdup() failed");
185 	env->len_identity = (unsigned int)strlen(env->identity);
186 	verbose(VERB_OPS, "dnstap identity field set to \"%s\"",
187 		env->identity);
188 }
189 
190 static void
191 dt_apply_version(struct dt_env *env, struct config_file *cfg)
192 {
193 	if (!cfg->dnstap_send_version)
194 		return;
195 	free(env->version);
196 	if (cfg->dnstap_version == NULL || cfg->dnstap_version[0] == 0)
197 		env->version = strdup(PACKAGE_STRING);
198 	else
199 		env->version = strdup(cfg->dnstap_version);
200 	if (env->version == NULL)
201 		fatal_exit("dt_apply_version: strdup() failed");
202 	env->len_version = (unsigned int)strlen(env->version);
203 	verbose(VERB_OPS, "dnstap version field set to \"%s\"",
204 		env->version);
205 }
206 
207 void
208 dt_apply_cfg(struct dt_env *env, struct config_file *cfg)
209 {
210 	if (!cfg->dnstap)
211 		return;
212 
213 	dt_apply_identity(env, cfg);
214 	dt_apply_version(env, cfg);
215 	if ((env->log_resolver_query_messages = (unsigned int)
216 	     cfg->dnstap_log_resolver_query_messages))
217 	{
218 		verbose(VERB_OPS, "dnstap Message/RESOLVER_QUERY enabled");
219 	}
220 	if ((env->log_resolver_response_messages = (unsigned int)
221 	     cfg->dnstap_log_resolver_response_messages))
222 	{
223 		verbose(VERB_OPS, "dnstap Message/RESOLVER_RESPONSE enabled");
224 	}
225 	if ((env->log_client_query_messages = (unsigned int)
226 	     cfg->dnstap_log_client_query_messages))
227 	{
228 		verbose(VERB_OPS, "dnstap Message/CLIENT_QUERY enabled");
229 	}
230 	if ((env->log_client_response_messages = (unsigned int)
231 	     cfg->dnstap_log_client_response_messages))
232 	{
233 		verbose(VERB_OPS, "dnstap Message/CLIENT_RESPONSE enabled");
234 	}
235 	if ((env->log_forwarder_query_messages = (unsigned int)
236 	     cfg->dnstap_log_forwarder_query_messages))
237 	{
238 		verbose(VERB_OPS, "dnstap Message/FORWARDER_QUERY enabled");
239 	}
240 	if ((env->log_forwarder_response_messages = (unsigned int)
241 	     cfg->dnstap_log_forwarder_response_messages))
242 	{
243 		verbose(VERB_OPS, "dnstap Message/FORWARDER_RESPONSE enabled");
244 	}
245 }
246 
247 int
248 dt_init(struct dt_env *env)
249 {
250 	env->ioq = fstrm_iothr_get_input_queue(env->iothr);
251 	if (env->ioq == NULL)
252 		return 0;
253 	return 1;
254 }
255 
256 void
257 dt_delete(struct dt_env *env)
258 {
259 	if (!env)
260 		return;
261 	verbose(VERB_OPS, "closing dnstap socket");
262 	fstrm_iothr_destroy(&env->iothr);
263 	free(env->identity);
264 	free(env->version);
265 	free(env);
266 }
267 
268 static void
269 dt_fill_timeval(const struct timeval *tv,
270 		uint64_t *time_sec, protobuf_c_boolean *has_time_sec,
271 		uint32_t *time_nsec, protobuf_c_boolean *has_time_nsec)
272 {
273 #ifndef S_SPLINT_S
274 	*time_sec = tv->tv_sec;
275 	*time_nsec = tv->tv_usec * 1000;
276 #endif
277 	*has_time_sec = 1;
278 	*has_time_nsec = 1;
279 }
280 
281 static void
282 dt_fill_buffer(sldns_buffer *b, ProtobufCBinaryData *p, protobuf_c_boolean *has)
283 {
284 	log_assert(b != NULL);
285 	p->len = sldns_buffer_limit(b);
286 	p->data = sldns_buffer_begin(b);
287 	*has = 1;
288 }
289 
290 static void
291 dt_msg_fill_net(struct dt_msg *dm,
292 		struct sockaddr_storage *ss,
293 		enum comm_point_type cptype,
294 		ProtobufCBinaryData *addr, protobuf_c_boolean *has_addr,
295 		uint32_t *port, protobuf_c_boolean *has_port)
296 {
297 	log_assert(ss->ss_family == AF_INET6 || ss->ss_family == AF_INET);
298 	if (ss->ss_family == AF_INET6) {
299 		struct sockaddr_in6 *s = (struct sockaddr_in6 *) ss;
300 
301 		/* socket_family */
302 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET6;
303 		dm->m.has_socket_family = 1;
304 
305 		/* addr: query_address or response_address */
306 		addr->data = s->sin6_addr.s6_addr;
307 		addr->len = 16; /* IPv6 */
308 		*has_addr = 1;
309 
310 		/* port: query_port or response_port */
311 		*port = ntohs(s->sin6_port);
312 		*has_port = 1;
313 	} else if (ss->ss_family == AF_INET) {
314 		struct sockaddr_in *s = (struct sockaddr_in *) ss;
315 
316 		/* socket_family */
317 		dm->m.socket_family = DNSTAP__SOCKET_FAMILY__INET;
318 		dm->m.has_socket_family = 1;
319 
320 		/* addr: query_address or response_address */
321 		addr->data = (uint8_t *) &s->sin_addr.s_addr;
322 		addr->len = 4; /* IPv4 */
323 		*has_addr = 1;
324 
325 		/* port: query_port or response_port */
326 		*port = ntohs(s->sin_port);
327 		*has_port = 1;
328 	}
329 
330 	log_assert(cptype == comm_udp || cptype == comm_tcp);
331 	if (cptype == comm_udp) {
332 		/* socket_protocol */
333 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__UDP;
334 		dm->m.has_socket_protocol = 1;
335 	} else if (cptype == comm_tcp) {
336 		/* socket_protocol */
337 		dm->m.socket_protocol = DNSTAP__SOCKET_PROTOCOL__TCP;
338 		dm->m.has_socket_protocol = 1;
339 	}
340 }
341 
342 void
343 dt_msg_send_client_query(struct dt_env *env,
344 			 struct sockaddr_storage *qsock,
345 			 enum comm_point_type cptype,
346 			 sldns_buffer *qmsg)
347 {
348 	struct dt_msg dm;
349 	struct timeval qtime;
350 
351 	gettimeofday(&qtime, NULL);
352 
353 	/* type */
354 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_QUERY);
355 
356 	/* query_time */
357 	dt_fill_timeval(&qtime,
358 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
359 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
360 
361 	/* query_message */
362 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
363 
364 	/* socket_family, socket_protocol, query_address, query_port */
365 	log_assert(cptype == comm_udp || cptype == comm_tcp);
366 	dt_msg_fill_net(&dm, qsock, cptype,
367 			&dm.m.query_address, &dm.m.has_query_address,
368 			&dm.m.query_port, &dm.m.has_query_port);
369 
370 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
371 		dt_send(env, dm.buf, dm.len_buf);
372 }
373 
374 void
375 dt_msg_send_client_response(struct dt_env *env,
376 			    struct sockaddr_storage *qsock,
377 			    enum comm_point_type cptype,
378 			    sldns_buffer *rmsg)
379 {
380 	struct dt_msg dm;
381 	struct timeval rtime;
382 
383 	gettimeofday(&rtime, NULL);
384 
385 	/* type */
386 	dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__CLIENT_RESPONSE);
387 
388 	/* response_time */
389 	dt_fill_timeval(&rtime,
390 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
391 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
392 
393 	/* response_message */
394 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
395 
396 	/* socket_family, socket_protocol, query_address, query_port */
397 	log_assert(cptype == comm_udp || cptype == comm_tcp);
398 	dt_msg_fill_net(&dm, qsock, cptype,
399 			&dm.m.query_address, &dm.m.has_query_address,
400 			&dm.m.query_port, &dm.m.has_query_port);
401 
402 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
403 		dt_send(env, dm.buf, dm.len_buf);
404 }
405 
406 void
407 dt_msg_send_outside_query(struct dt_env *env,
408 			  struct sockaddr_storage *rsock,
409 			  enum comm_point_type cptype,
410 			  uint8_t *zone, size_t zone_len,
411 			  sldns_buffer *qmsg)
412 {
413 	struct dt_msg dm;
414 	struct timeval qtime;
415 	uint16_t qflags;
416 
417 	gettimeofday(&qtime, NULL);
418 	qflags = sldns_buffer_read_u16_at(qmsg, 2);
419 
420 	/* type */
421 	if (qflags & BIT_RD) {
422 		if (!env->log_forwarder_query_messages)
423 			return;
424 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_QUERY);
425 	} else {
426 		if (!env->log_resolver_query_messages)
427 			return;
428 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_QUERY);
429 	}
430 
431 	/* query_zone */
432 	dm.m.query_zone.data = zone;
433 	dm.m.query_zone.len = zone_len;
434 	dm.m.has_query_zone = 1;
435 
436 	/* query_time_sec, query_time_nsec */
437 	dt_fill_timeval(&qtime,
438 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
439 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
440 
441 	/* query_message */
442 	dt_fill_buffer(qmsg, &dm.m.query_message, &dm.m.has_query_message);
443 
444 	/* socket_family, socket_protocol, response_address, response_port */
445 	log_assert(cptype == comm_udp || cptype == comm_tcp);
446 	dt_msg_fill_net(&dm, rsock, cptype,
447 			&dm.m.response_address, &dm.m.has_response_address,
448 			&dm.m.response_port, &dm.m.has_response_port);
449 
450 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
451 		dt_send(env, dm.buf, dm.len_buf);
452 }
453 
454 void
455 dt_msg_send_outside_response(struct dt_env *env,
456 			     struct sockaddr_storage *rsock,
457 			     enum comm_point_type cptype,
458 			     uint8_t *zone, size_t zone_len,
459 			     uint8_t *qbuf, size_t qbuf_len,
460 			     const struct timeval *qtime,
461 			     const struct timeval *rtime,
462 			     sldns_buffer *rmsg)
463 {
464 	struct dt_msg dm;
465 	uint16_t qflags;
466 
467 	log_assert(qbuf_len >= sizeof(qflags));
468 	memcpy(&qflags, qbuf, sizeof(qflags));
469 	qflags = ntohs(qflags);
470 
471 	/* type */
472 	if (qflags & BIT_RD) {
473 		if (!env->log_forwarder_response_messages)
474 			return;
475 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__FORWARDER_RESPONSE);
476 	} else {
477 		if (!env->log_resolver_query_messages)
478 			return;
479 		dt_msg_init(env, &dm, DNSTAP__MESSAGE__TYPE__RESOLVER_RESPONSE);
480 	}
481 
482 	/* query_zone */
483 	dm.m.query_zone.data = zone;
484 	dm.m.query_zone.len = zone_len;
485 	dm.m.has_query_zone = 1;
486 
487 	/* query_time_sec, query_time_nsec */
488 	dt_fill_timeval(qtime,
489 			&dm.m.query_time_sec, &dm.m.has_query_time_sec,
490 			&dm.m.query_time_nsec, &dm.m.has_query_time_nsec);
491 
492 	/* response_time_sec, response_time_nsec */
493 	dt_fill_timeval(rtime,
494 			&dm.m.response_time_sec, &dm.m.has_response_time_sec,
495 			&dm.m.response_time_nsec, &dm.m.has_response_time_nsec);
496 
497 	/* response_message */
498 	dt_fill_buffer(rmsg, &dm.m.response_message, &dm.m.has_response_message);
499 
500 	/* socket_family, socket_protocol, response_address, response_port */
501 	log_assert(cptype == comm_udp || cptype == comm_tcp);
502 	dt_msg_fill_net(&dm, rsock, cptype,
503 			&dm.m.response_address, &dm.m.has_response_address,
504 			&dm.m.response_port, &dm.m.has_response_port);
505 
506 	if (dt_pack(&dm.d, &dm.buf, &dm.len_buf))
507 		dt_send(env, dm.buf, dm.len_buf);
508 }
509 
510 #endif /* USE_DNSTAP */
511