1 /*
2  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
3  *
4  * This Source Code Form is subject to the terms of the Mozilla Public
5  * License, v. 2.0. If a copy of the MPL was not distributed with this
6  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
7  *
8  * See the COPYRIGHT file distributed with this work for additional
9  * information regarding copyright ownership.
10  */
11 
12 /*! \file */
13 
14 #include <config.h>
15 
16 #include <inttypes.h>
17 #include <stdbool.h>
18 
19 #include <isc/base64.h>
20 #include <isc/buffer.h>
21 #include <isc/event.h>
22 #include <isc/file.h>
23 #include <isc/mem.h>
24 #include <isc/mutex.h>
25 #include <isc/net.h>
26 #include <isc/netaddr.h>
27 #include <isc/random.h>
28 #include <isc/result.h>
29 #include <isc/stdtime.h>
30 #include <isc/string.h>
31 #include <isc/timer.h>
32 #include <isc/util.h>
33 
34 #include <isccfg/namedconf.h>
35 
36 #include <bind9/check.h>
37 
38 #include <isccc/alist.h>
39 #include <isccc/cc.h>
40 #include <isccc/ccmsg.h>
41 #include <isccc/events.h>
42 #include <isccc/result.h>
43 #include <isccc/sexpr.h>
44 #include <isccc/symtab.h>
45 #include <isccc/util.h>
46 
47 #include <dns/result.h>
48 
49 #include <named/config.h>
50 #include <named/control.h>
51 #include <named/log.h>
52 #include <named/server.h>
53 
54 /*
55  * Note: Listeners and connections are not locked.  All event handlers are
56  * executed by the server task, and all callers of exported routines must
57  * be running under the server task.
58  */
59 
60 typedef struct controlkey controlkey_t;
61 typedef ISC_LIST(controlkey_t) controlkeylist_t;
62 
63 typedef struct controlconnection controlconnection_t;
64 typedef ISC_LIST(controlconnection_t) controlconnectionlist_t;
65 
66 typedef struct controllistener controllistener_t;
67 typedef ISC_LIST(controllistener_t) controllistenerlist_t;
68 
69 struct controlkey {
70 	char *				keyname;
71 	uint32_t			algorithm;
72 	isc_region_t			secret;
73 	ISC_LINK(controlkey_t)		link;
74 };
75 
76 struct controlconnection {
77 	isc_socket_t *			sock;
78 	isccc_ccmsg_t			ccmsg;
79 	bool				ccmsg_valid;
80 	bool				sending;
81 	isc_timer_t *			timer;
82 	isc_buffer_t *			buffer;
83 	controllistener_t *		listener;
84 	uint32_t			nonce;
85 	ISC_LINK(controlconnection_t)	link;
86 };
87 
88 struct controllistener {
89 	ns_controls_t *			controls;
90 	isc_mem_t *			mctx;
91 	isc_task_t *			task;
92 	isc_sockaddr_t			address;
93 	isc_socket_t *			sock;
94 	dns_acl_t *			acl;
95 	bool				listening;
96 	bool				exiting;
97 	controlkeylist_t		keys;
98 	controlconnectionlist_t		connections;
99 	isc_sockettype_t		type;
100 	uint32_t			perm;
101 	uint32_t			owner;
102 	uint32_t			group;
103 	bool				readonly;
104 	ISC_LINK(controllistener_t)	link;
105 };
106 
107 struct ns_controls {
108 	ns_server_t			*server;
109 	controllistenerlist_t 		listeners;
110 	bool				shuttingdown;
111 	isc_mutex_t			symtab_lock;
112 	isccc_symtab_t			*symtab;
113 };
114 
115 static void control_newconn(isc_task_t *task, isc_event_t *event);
116 static void control_recvmessage(isc_task_t *task, isc_event_t *event);
117 
118 #define CLOCKSKEW 300
119 
120 static void
free_controlkey(controlkey_t * key,isc_mem_t * mctx)121 free_controlkey(controlkey_t *key, isc_mem_t *mctx) {
122 	if (key->keyname != NULL)
123 		isc_mem_free(mctx, key->keyname);
124 	if (key->secret.base != NULL)
125 		isc_mem_put(mctx, key->secret.base, key->secret.length);
126 	isc_mem_put(mctx, key, sizeof(*key));
127 }
128 
129 static void
free_controlkeylist(controlkeylist_t * keylist,isc_mem_t * mctx)130 free_controlkeylist(controlkeylist_t *keylist, isc_mem_t *mctx) {
131 	while (!ISC_LIST_EMPTY(*keylist)) {
132 		controlkey_t *key = ISC_LIST_HEAD(*keylist);
133 		ISC_LIST_UNLINK(*keylist, key, link);
134 		free_controlkey(key, mctx);
135 	}
136 }
137 
138 static void
free_listener(controllistener_t * listener)139 free_listener(controllistener_t *listener) {
140 	INSIST(listener->exiting);
141 	INSIST(!listener->listening);
142 	INSIST(ISC_LIST_EMPTY(listener->connections));
143 
144 	if (listener->sock != NULL)
145 		isc_socket_detach(&listener->sock);
146 
147 	free_controlkeylist(&listener->keys, listener->mctx);
148 
149 	if (listener->acl != NULL)
150 		dns_acl_detach(&listener->acl);
151 
152 	isc_mem_putanddetach(&listener->mctx, listener, sizeof(*listener));
153 }
154 
155 static void
maybe_free_listener(controllistener_t * listener)156 maybe_free_listener(controllistener_t *listener) {
157 	if (listener->exiting &&
158 	    !listener->listening &&
159 	    ISC_LIST_EMPTY(listener->connections))
160 		free_listener(listener);
161 }
162 
163 static void
maybe_free_connection(controlconnection_t * conn)164 maybe_free_connection(controlconnection_t *conn) {
165 	controllistener_t *listener = conn->listener;
166 
167 	if (conn->buffer != NULL)
168 		isc_buffer_free(&conn->buffer);
169 
170 	if (conn->timer != NULL)
171 		isc_timer_detach(&conn->timer);
172 
173 	if (conn->ccmsg_valid) {
174 		isccc_ccmsg_cancelread(&conn->ccmsg);
175 		return;
176 	}
177 
178 	if (conn->sending) {
179 		isc_socket_cancel(conn->sock, listener->task,
180 				  ISC_SOCKCANCEL_SEND);
181 		return;
182 	}
183 
184 	ISC_LIST_UNLINK(listener->connections, conn, link);
185 #ifdef ENABLE_AFL
186 	if (ns_g_fuzz_type == ns_fuzz_rndc) {
187 		named_fuzz_notify();
188 	}
189 #endif
190 	isc_mem_put(listener->mctx, conn, sizeof(*conn));
191 }
192 
193 static void
shutdown_listener(controllistener_t * listener)194 shutdown_listener(controllistener_t *listener) {
195 	controlconnection_t *conn;
196 	controlconnection_t *next;
197 
198 	if (!listener->exiting) {
199 		char socktext[ISC_SOCKADDR_FORMATSIZE];
200 
201 		ISC_LIST_UNLINK(listener->controls->listeners, listener, link);
202 
203 		isc_sockaddr_format(&listener->address, socktext,
204 				    sizeof(socktext));
205 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
206 			      NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE,
207 			      "stopping command channel on %s", socktext);
208 		if (listener->type == isc_sockettype_unix)
209 			isc_socket_cleanunix(&listener->address, true);
210 		listener->exiting = true;
211 	}
212 
213 	for (conn = ISC_LIST_HEAD(listener->connections);
214 	     conn != NULL;
215 	     conn = next)
216 	{
217 		next = ISC_LIST_NEXT(conn, link);
218 		maybe_free_connection(conn);
219 	}
220 
221 	if (listener->listening)
222 		isc_socket_cancel(listener->sock, listener->task,
223 				  ISC_SOCKCANCEL_ACCEPT);
224 
225 	maybe_free_listener(listener);
226 }
227 
228 static bool
address_ok(isc_sockaddr_t * sockaddr,dns_acl_t * acl)229 address_ok(isc_sockaddr_t *sockaddr, dns_acl_t *acl) {
230 	isc_netaddr_t netaddr;
231 	isc_result_t result;
232 	int match;
233 
234 	isc_netaddr_fromsockaddr(&netaddr, sockaddr);
235 
236 	result = dns_acl_match(&netaddr, NULL, acl,
237 			       &ns_g_server->aclenv, &match, NULL);
238 
239 	if (result != ISC_R_SUCCESS || match <= 0)
240 		return (false);
241 	else
242 		return (true);
243 }
244 
245 static isc_result_t
control_accept(controllistener_t * listener)246 control_accept(controllistener_t *listener) {
247 	isc_result_t result;
248 	result = isc_socket_accept(listener->sock,
249 				   listener->task,
250 				   control_newconn, listener);
251 	if (result != ISC_R_SUCCESS)
252 		UNEXPECTED_ERROR(__FILE__, __LINE__,
253 				 "isc_socket_accept() failed: %s",
254 				 isc_result_totext(result));
255 	else
256 		listener->listening = true;
257 	return (result);
258 }
259 
260 static isc_result_t
control_listen(controllistener_t * listener)261 control_listen(controllistener_t *listener) {
262 	isc_result_t result;
263 
264 	result = isc_socket_listen(listener->sock, 0);
265 	if (result != ISC_R_SUCCESS)
266 		UNEXPECTED_ERROR(__FILE__, __LINE__,
267 				 "isc_socket_listen() failed: %s",
268 				 isc_result_totext(result));
269 	return (result);
270 }
271 
272 static void
control_next(controllistener_t * listener)273 control_next(controllistener_t *listener) {
274 	(void)control_accept(listener);
275 }
276 
277 static void
control_senddone(isc_task_t * task,isc_event_t * event)278 control_senddone(isc_task_t *task, isc_event_t *event) {
279 	isc_socketevent_t *sevent = (isc_socketevent_t *) event;
280 	controlconnection_t *conn = event->ev_arg;
281 	controllistener_t *listener = conn->listener;
282 	isc_socket_t *sock = (isc_socket_t *)sevent->ev_sender;
283 	isc_result_t result;
284 
285 	REQUIRE(conn->sending);
286 
287 	UNUSED(task);
288 
289 	conn->sending = false;
290 
291 	if (sevent->result != ISC_R_SUCCESS &&
292 	    sevent->result != ISC_R_CANCELED)
293 	{
294 		char socktext[ISC_SOCKADDR_FORMATSIZE];
295 		isc_sockaddr_t peeraddr;
296 
297 		(void)isc_socket_getpeername(sock, &peeraddr);
298 		isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
299 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
300 			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
301 			      "error sending command response to %s: %s",
302 			      socktext, isc_result_totext(sevent->result));
303 	}
304 	isc_event_free(&event);
305 
306 	result = isccc_ccmsg_readmessage(&conn->ccmsg, listener->task,
307 					 control_recvmessage, conn);
308 	if (result != ISC_R_SUCCESS) {
309 		isc_socket_detach(&conn->sock);
310 		maybe_free_connection(conn);
311 		maybe_free_listener(listener);
312 	}
313 }
314 
315 static inline void
log_invalid(isccc_ccmsg_t * ccmsg,isc_result_t result)316 log_invalid(isccc_ccmsg_t *ccmsg, isc_result_t result) {
317 	char socktext[ISC_SOCKADDR_FORMATSIZE];
318 	isc_sockaddr_t peeraddr;
319 
320 	(void)isc_socket_getpeername(ccmsg->sock, &peeraddr);
321 	isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
322 	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
323 		      NS_LOGMODULE_CONTROL, ISC_LOG_ERROR,
324 		      "invalid command from %s: %s",
325 		      socktext, isc_result_totext(result));
326 }
327 
328 static void
control_recvmessage(isc_task_t * task,isc_event_t * event)329 control_recvmessage(isc_task_t *task, isc_event_t *event) {
330 	controlconnection_t *conn;
331 	controllistener_t *listener;
332 	controlkey_t *key;
333 	isccc_sexpr_t *request = NULL;
334 	isccc_sexpr_t *response = NULL;
335 	uint32_t algorithm;
336 	isccc_region_t secret;
337 	isc_stdtime_t now;
338 	isc_buffer_t b;
339 	isc_region_t r;
340 	isc_buffer_t *text;
341 	isc_result_t result;
342 	isc_result_t eresult;
343 	isccc_sexpr_t *_ctrl;
344 	isccc_time_t sent;
345 	isccc_time_t exp;
346 	uint32_t nonce;
347 	isccc_sexpr_t *data;
348 
349 	REQUIRE(event->ev_type == ISCCC_EVENT_CCMSG);
350 
351 	conn = event->ev_arg;
352 	listener = conn->listener;
353 	algorithm = DST_ALG_UNKNOWN;
354 	secret.rstart = NULL;
355 	text = NULL;
356 
357 	/* Is the server shutting down? */
358 	if (listener->controls->shuttingdown)
359 		goto cleanup;
360 
361 	if (conn->ccmsg.result != ISC_R_SUCCESS) {
362 		if (conn->ccmsg.result != ISC_R_CANCELED &&
363 		    conn->ccmsg.result != ISC_R_EOF)
364 			log_invalid(&conn->ccmsg, conn->ccmsg.result);
365 		goto cleanup;
366 	}
367 
368 	request = NULL;
369 
370 	for (key = ISC_LIST_HEAD(listener->keys);
371 	     key != NULL;
372 	     key = ISC_LIST_NEXT(key, link))
373 	{
374 		isccc_region_t ccregion;
375 
376 		ccregion.rstart = isc_buffer_base(&conn->ccmsg.buffer);
377 		ccregion.rend = isc_buffer_used(&conn->ccmsg.buffer);
378 		secret.rstart = isc_mem_get(listener->mctx, key->secret.length);
379 		if (secret.rstart == NULL)
380 			goto cleanup;
381 		memmove(secret.rstart, key->secret.base, key->secret.length);
382 		secret.rend = secret.rstart + key->secret.length;
383 		algorithm = key->algorithm;
384 		result = isccc_cc_fromwire(&ccregion, &request,
385 					   algorithm, &secret);
386 		if (result == ISC_R_SUCCESS)
387 			break;
388 		isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret));
389 		if (result != ISCCC_R_BADAUTH) {
390 			log_invalid(&conn->ccmsg, result);
391 			goto cleanup;
392 		}
393 	}
394 
395 	if (key == NULL) {
396 		log_invalid(&conn->ccmsg, ISCCC_R_BADAUTH);
397 		goto cleanup;
398 	}
399 
400 	/* We shouldn't be getting a reply. */
401 	if (isccc_cc_isreply(request)) {
402 		log_invalid(&conn->ccmsg, ISC_R_FAILURE);
403 		goto cleanup_request;
404 	}
405 
406 	isc_stdtime_get(&now);
407 
408 	/*
409 	 * Limit exposure to replay attacks.
410 	 */
411 	_ctrl = isccc_alist_lookup(request, "_ctrl");
412 	if (!isccc_alist_alistp(_ctrl)) {
413 		log_invalid(&conn->ccmsg, ISC_R_FAILURE);
414 		goto cleanup_request;
415 	}
416 
417 	if (isccc_cc_lookupuint32(_ctrl, "_tim", &sent) == ISC_R_SUCCESS) {
418 		if ((sent + CLOCKSKEW) < now || (sent - CLOCKSKEW) > now) {
419 			log_invalid(&conn->ccmsg, ISCCC_R_CLOCKSKEW);
420 			goto cleanup_request;
421 		}
422 	} else {
423 		log_invalid(&conn->ccmsg, ISC_R_FAILURE);
424 		goto cleanup_request;
425 	}
426 
427 	/*
428 	 * Expire messages that are too old.
429 	 */
430 	if (isccc_cc_lookupuint32(_ctrl, "_exp", &exp) == ISC_R_SUCCESS &&
431 	    now > exp) {
432 		log_invalid(&conn->ccmsg, ISCCC_R_EXPIRED);
433 		goto cleanup_request;
434 	}
435 
436 	/*
437 	 * Duplicate suppression (required for UDP).
438 	 */
439 	LOCK(&listener->controls->symtab_lock);
440 	isccc_cc_cleansymtab(listener->controls->symtab, now);
441 	result = isccc_cc_checkdup(listener->controls->symtab, request, now);
442 	UNLOCK(&listener->controls->symtab_lock);
443 	if (result != ISC_R_SUCCESS) {
444 		if (result == ISC_R_EXISTS)
445 			result = ISCCC_R_DUPLICATE;
446 		log_invalid(&conn->ccmsg, result);
447 		goto cleanup_request;
448 	}
449 
450 	if (conn->nonce != 0 &&
451 	    (isccc_cc_lookupuint32(_ctrl, "_nonce", &nonce) != ISC_R_SUCCESS ||
452 	     conn->nonce != nonce)) {
453 		log_invalid(&conn->ccmsg, ISCCC_R_BADAUTH);
454 		goto cleanup_request;
455 	}
456 
457 	result = isc_buffer_allocate(listener->mctx, &text, 2 * 2048);
458 	if (result != ISC_R_SUCCESS)
459 		goto cleanup_request;
460 
461 	/*
462 	 * Establish nonce.
463 	 */
464 	if (conn->nonce == 0) {
465 		while (conn->nonce == 0)
466 			isc_random_get(&conn->nonce);
467 		eresult = ISC_R_SUCCESS;
468 	} else
469 		eresult = ns_control_docommand(request, listener->readonly, &text);
470 
471 	result = isccc_cc_createresponse(request, now, now + 60, &response);
472 	if (result != ISC_R_SUCCESS)
473 		goto cleanup_request;
474 
475 	data = isccc_alist_lookup(response, "_data");
476 	if (data != NULL) {
477 		if (isccc_cc_defineuint32(data, "result", eresult) == NULL)
478 			goto cleanup_response;
479 	}
480 
481 	if (eresult != ISC_R_SUCCESS) {
482 		if (data != NULL) {
483 			const char *estr = isc_result_totext(eresult);
484 			if (isccc_cc_definestring(data, "err", estr) == NULL)
485 				goto cleanup_response;
486 		}
487 	}
488 
489 	if (isc_buffer_usedlength(text) > 0) {
490 		if (data != NULL) {
491 			char *str = (char *)isc_buffer_base(text);
492 			if (isccc_cc_definestring(data, "text", str) == NULL)
493 				goto cleanup_response;
494 		}
495 	}
496 
497 	_ctrl = isccc_alist_lookup(response, "_ctrl");
498 	if (_ctrl == NULL ||
499 	    isccc_cc_defineuint32(_ctrl, "_nonce", conn->nonce) == NULL)
500 		goto cleanup_response;
501 
502 	if (conn->buffer == NULL) {
503 		result = isc_buffer_allocate(listener->mctx,
504 					     &conn->buffer, 2 * 2048);
505 		if (result != ISC_R_SUCCESS)
506 			goto cleanup_response;
507 	}
508 
509 	isc_buffer_clear(conn->buffer);
510 	/* Skip the length field (4 bytes) */
511 	isc_buffer_add(conn->buffer, 4);
512 
513 	result = isccc_cc_towire(response, &conn->buffer, algorithm, &secret);
514 	if (result != ISC_R_SUCCESS)
515 		goto cleanup_response;
516 
517 	isc_buffer_init(&b, conn->buffer->base, 4);
518 	isc_buffer_putuint32(&b, conn->buffer->used - 4);
519 
520 	r.base = conn->buffer->base;
521 	r.length = conn->buffer->used;
522 
523 	result = isc_socket_send(conn->sock, &r, task, control_senddone, conn);
524 	if (result != ISC_R_SUCCESS)
525 		goto cleanup_response;
526 	conn->sending = true;
527 
528 	isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret));
529 	isccc_sexpr_free(&request);
530 	isccc_sexpr_free(&response);
531 	isc_buffer_free(&text);
532 	return;
533 
534  cleanup_response:
535 	isccc_sexpr_free(&response);
536 
537  cleanup_request:
538 	isccc_sexpr_free(&request);
539 	isc_mem_put(listener->mctx, secret.rstart, REGION_SIZE(secret));
540 	if (text != NULL)
541 		isc_buffer_free(&text);
542 
543  cleanup:
544 	isc_socket_detach(&conn->sock);
545 	isccc_ccmsg_invalidate(&conn->ccmsg);
546 	conn->ccmsg_valid = false;
547 	maybe_free_connection(conn);
548 	maybe_free_listener(listener);
549 }
550 
551 static void
control_timeout(isc_task_t * task,isc_event_t * event)552 control_timeout(isc_task_t *task, isc_event_t *event) {
553 	controlconnection_t *conn = event->ev_arg;
554 
555 	UNUSED(task);
556 
557 	isc_timer_detach(&conn->timer);
558 	maybe_free_connection(conn);
559 
560 	isc_event_free(&event);
561 }
562 
563 static isc_result_t
newconnection(controllistener_t * listener,isc_socket_t * sock)564 newconnection(controllistener_t *listener, isc_socket_t *sock) {
565 	controlconnection_t *conn;
566 	isc_interval_t interval;
567 	isc_result_t result;
568 
569 	conn = isc_mem_get(listener->mctx, sizeof(*conn));
570 	if (conn == NULL)
571 		return (ISC_R_NOMEMORY);
572 
573 	conn->sock = sock;
574 	isccc_ccmsg_init(listener->mctx, sock, &conn->ccmsg);
575 
576 	/* Set a 32 KiB upper limit on incoming message. */
577 	isccc_ccmsg_setmaxsize(&conn->ccmsg, 32768);
578 
579 	conn->ccmsg_valid = true;
580 	conn->sending = false;
581 	conn->buffer = NULL;
582 	conn->timer = NULL;
583 	isc_interval_set(&interval, 60, 0);
584 	result = isc_timer_create(ns_g_timermgr, isc_timertype_once,
585 				  NULL, &interval, listener->task,
586 				  control_timeout, conn, &conn->timer);
587 	if (result != ISC_R_SUCCESS)
588 		goto cleanup;
589 
590 	conn->listener = listener;
591 	conn->nonce = 0;
592 	ISC_LINK_INIT(conn, link);
593 
594 	result = isccc_ccmsg_readmessage(&conn->ccmsg, listener->task,
595 					 control_recvmessage, conn);
596 	if (result != ISC_R_SUCCESS)
597 		goto cleanup;
598 
599 	ISC_LIST_APPEND(listener->connections, conn, link);
600 	return (ISC_R_SUCCESS);
601 
602  cleanup:
603 	if (conn->buffer != NULL)
604 		isc_buffer_free(&conn->buffer);
605 	isccc_ccmsg_invalidate(&conn->ccmsg);
606 	if (conn->timer != NULL)
607 		isc_timer_detach(&conn->timer);
608 	isc_mem_put(listener->mctx, conn, sizeof(*conn));
609 #ifdef ENABLE_AFL
610 	if (ns_g_fuzz_type == ns_fuzz_rndc) {
611 		named_fuzz_notify();
612 	}
613 #endif
614 	return (result);
615 }
616 
617 static void
control_newconn(isc_task_t * task,isc_event_t * event)618 control_newconn(isc_task_t *task, isc_event_t *event) {
619 	isc_socket_newconnev_t *nevent = (isc_socket_newconnev_t *)event;
620 	controllistener_t *listener = event->ev_arg;
621 	isc_socket_t *sock;
622 	isc_sockaddr_t peeraddr;
623 	isc_result_t result;
624 
625 	UNUSED(task);
626 
627 	listener->listening = false;
628 
629 	if (nevent->result != ISC_R_SUCCESS) {
630 		if (nevent->result == ISC_R_CANCELED) {
631 			shutdown_listener(listener);
632 			goto cleanup;
633 		}
634 		goto restart;
635 	}
636 
637 	sock = nevent->newsocket;
638 	isc_socket_setname(sock, "control", NULL);
639 	(void)isc_socket_getpeername(sock, &peeraddr);
640 	if (listener->type == isc_sockettype_tcp &&
641 	    !address_ok(&peeraddr, listener->acl)) {
642 		char socktext[ISC_SOCKADDR_FORMATSIZE];
643 		isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
644 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
645 			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
646 			      "rejected command channel message from %s",
647 			      socktext);
648 		isc_socket_detach(&sock);
649 		goto restart;
650 	}
651 
652 	result = newconnection(listener, sock);
653 	if (result != ISC_R_SUCCESS) {
654 		char socktext[ISC_SOCKADDR_FORMATSIZE];
655 		isc_sockaddr_format(&peeraddr, socktext, sizeof(socktext));
656 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
657 			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
658 			      "dropped command channel from %s: %s",
659 			      socktext, isc_result_totext(result));
660 		isc_socket_detach(&sock);
661 		goto restart;
662 	}
663 
664  restart:
665 	control_next(listener);
666  cleanup:
667 	isc_event_free(&event);
668 }
669 
670 static void
controls_shutdown(ns_controls_t * controls)671 controls_shutdown(ns_controls_t *controls) {
672 	controllistener_t *listener;
673 	controllistener_t *next;
674 
675 	for (listener = ISC_LIST_HEAD(controls->listeners);
676 	     listener != NULL;
677 	     listener = next)
678 	{
679 		/*
680 		 * This is asynchronous.  As listeners shut down, they will
681 		 * call their callbacks.
682 		 */
683 		next = ISC_LIST_NEXT(listener, link);
684 		shutdown_listener(listener);
685 	}
686 }
687 
688 void
ns_controls_shutdown(ns_controls_t * controls)689 ns_controls_shutdown(ns_controls_t *controls) {
690 	controls_shutdown(controls);
691 	controls->shuttingdown = true;
692 }
693 
694 static isc_result_t
cfgkeylist_find(const cfg_obj_t * keylist,const char * keyname,const cfg_obj_t ** objp)695 cfgkeylist_find(const cfg_obj_t *keylist, const char *keyname,
696 		const cfg_obj_t **objp)
697 {
698 	const cfg_listelt_t *element;
699 	const char *str;
700 	const cfg_obj_t *obj;
701 
702 	for (element = cfg_list_first(keylist);
703 	     element != NULL;
704 	     element = cfg_list_next(element))
705 	{
706 		obj = cfg_listelt_value(element);
707 		str = cfg_obj_asstring(cfg_map_getname(obj));
708 		if (strcasecmp(str, keyname) == 0)
709 			break;
710 	}
711 	if (element == NULL)
712 		return (ISC_R_NOTFOUND);
713 	obj = cfg_listelt_value(element);
714 	*objp = obj;
715 	return (ISC_R_SUCCESS);
716 }
717 
718 static isc_result_t
controlkeylist_fromcfg(const cfg_obj_t * keylist,isc_mem_t * mctx,controlkeylist_t * keyids)719 controlkeylist_fromcfg(const cfg_obj_t *keylist, isc_mem_t *mctx,
720 		       controlkeylist_t *keyids)
721 {
722 	const cfg_listelt_t *element;
723 	char *newstr = NULL;
724 	const char *str;
725 	const cfg_obj_t *obj;
726 	controlkey_t *key;
727 
728 	for (element = cfg_list_first(keylist);
729 	     element != NULL;
730 	     element = cfg_list_next(element))
731 	{
732 		obj = cfg_listelt_value(element);
733 		str = cfg_obj_asstring(obj);
734 		newstr = isc_mem_strdup(mctx, str);
735 		if (newstr == NULL)
736 			goto cleanup;
737 		key = isc_mem_get(mctx, sizeof(*key));
738 		if (key == NULL)
739 			goto cleanup;
740 		key->keyname = newstr;
741 		key->algorithm = DST_ALG_UNKNOWN;
742 		key->secret.base = NULL;
743 		key->secret.length = 0;
744 		ISC_LINK_INIT(key, link);
745 		ISC_LIST_APPEND(*keyids, key, link);
746 		newstr = NULL;
747 	}
748 	return (ISC_R_SUCCESS);
749 
750  cleanup:
751 	if (newstr != NULL)
752 		isc_mem_free(mctx, newstr);
753 	free_controlkeylist(keyids, mctx);
754 	return (ISC_R_NOMEMORY);
755 }
756 
757 static void
register_keys(const cfg_obj_t * control,const cfg_obj_t * keylist,controlkeylist_t * keyids,isc_mem_t * mctx,const char * socktext)758 register_keys(const cfg_obj_t *control, const cfg_obj_t *keylist,
759 	      controlkeylist_t *keyids, isc_mem_t *mctx, const char *socktext)
760 {
761 	controlkey_t *keyid, *next;
762 	const cfg_obj_t *keydef;
763 	char secret[1024];
764 	isc_buffer_t b;
765 	isc_result_t result;
766 
767 	/*
768 	 * Find the keys corresponding to the keyids used by this listener.
769 	 */
770 	for (keyid = ISC_LIST_HEAD(*keyids); keyid != NULL; keyid = next) {
771 		next = ISC_LIST_NEXT(keyid, link);
772 
773 		result = cfgkeylist_find(keylist, keyid->keyname, &keydef);
774 		if (result != ISC_R_SUCCESS) {
775 			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
776 				    "couldn't find key '%s' for use with "
777 				    "command channel %s",
778 				    keyid->keyname, socktext);
779 			ISC_LIST_UNLINK(*keyids, keyid, link);
780 			free_controlkey(keyid, mctx);
781 		} else {
782 			const cfg_obj_t *algobj = NULL;
783 			const cfg_obj_t *secretobj = NULL;
784 			const char *algstr = NULL;
785 			const char *secretstr = NULL;
786 			unsigned int algtype;
787 
788 			(void)cfg_map_get(keydef, "algorithm", &algobj);
789 			(void)cfg_map_get(keydef, "secret", &secretobj);
790 			INSIST(algobj != NULL && secretobj != NULL);
791 
792 			algstr = cfg_obj_asstring(algobj);
793 			secretstr = cfg_obj_asstring(secretobj);
794 
795 			if (ns_config_getkeyalgorithm2(algstr, NULL,
796 					&algtype, NULL) != ISC_R_SUCCESS)
797 			{
798 				cfg_obj_log(control, ns_g_lctx,
799 					    ISC_LOG_WARNING,
800 					    "unsupported algorithm '%s' in "
801 					    "key '%s' for use with command "
802 					    "channel %s",
803 					    algstr, keyid->keyname, socktext);
804 				ISC_LIST_UNLINK(*keyids, keyid, link);
805 				free_controlkey(keyid, mctx);
806 				continue;
807 			}
808 
809 			keyid->algorithm = algtype;
810 			isc_buffer_init(&b, secret, sizeof(secret));
811 			result = isc_base64_decodestring(secretstr, &b);
812 
813 			if (result != ISC_R_SUCCESS) {
814 				cfg_obj_log(keydef, ns_g_lctx, ISC_LOG_WARNING,
815 					    "secret for key '%s' on "
816 					    "command channel %s: %s",
817 					    keyid->keyname, socktext,
818 					    isc_result_totext(result));
819 				ISC_LIST_UNLINK(*keyids, keyid, link);
820 				free_controlkey(keyid, mctx);
821 				continue;
822 			}
823 
824 			keyid->secret.length = isc_buffer_usedlength(&b);
825 			keyid->secret.base = isc_mem_get(mctx,
826 							 keyid->secret.length);
827 			if (keyid->secret.base == NULL) {
828 				cfg_obj_log(keydef, ns_g_lctx, ISC_LOG_WARNING,
829 					   "couldn't register key '%s': "
830 					   "out of memory", keyid->keyname);
831 				ISC_LIST_UNLINK(*keyids, keyid, link);
832 				free_controlkey(keyid, mctx);
833 				break;
834 			}
835 			memmove(keyid->secret.base, isc_buffer_base(&b),
836 				keyid->secret.length);
837 		}
838 	}
839 }
840 
841 #define CHECK(x) \
842 	do { \
843 		 result = (x); \
844 		 if (result != ISC_R_SUCCESS) \
845 			goto cleanup; \
846 	} while (0)
847 
848 static isc_result_t
get_rndckey(isc_mem_t * mctx,controlkeylist_t * keyids)849 get_rndckey(isc_mem_t *mctx, controlkeylist_t *keyids) {
850 	isc_result_t result;
851 	cfg_parser_t *pctx = NULL;
852 	cfg_obj_t *config = NULL;
853 	const cfg_obj_t *key = NULL;
854 	const cfg_obj_t *algobj = NULL;
855 	const cfg_obj_t *secretobj = NULL;
856 	const char *algstr = NULL;
857 	const char *secretstr = NULL;
858 	controlkey_t *keyid = NULL;
859 	char secret[1024];
860 	unsigned int algtype;
861 	isc_buffer_t b;
862 
863 	isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
864 		      NS_LOGMODULE_CONTROL, ISC_LOG_INFO,
865 		      "configuring command channel from '%s'",
866 		      ns_g_keyfile);
867 	if (! isc_file_exists(ns_g_keyfile))
868 		return (ISC_R_FILENOTFOUND);
869 
870 	CHECK(cfg_parser_create(mctx, ns_g_lctx, &pctx));
871 	CHECK(cfg_parse_file(pctx, ns_g_keyfile, &cfg_type_rndckey, &config));
872 	CHECK(cfg_map_get(config, "key", &key));
873 
874 	keyid = isc_mem_get(mctx, sizeof(*keyid));
875 	if (keyid == NULL)
876 		CHECK(ISC_R_NOMEMORY);
877 	keyid->keyname = isc_mem_strdup(mctx,
878 					cfg_obj_asstring(cfg_map_getname(key)));
879 	keyid->secret.base = NULL;
880 	keyid->secret.length = 0;
881 	keyid->algorithm = DST_ALG_UNKNOWN;
882 	ISC_LINK_INIT(keyid, link);
883 	if (keyid->keyname == NULL)
884 		CHECK(ISC_R_NOMEMORY);
885 
886 	CHECK(bind9_check_key(key, ns_g_lctx));
887 
888 	(void)cfg_map_get(key, "algorithm", &algobj);
889 	(void)cfg_map_get(key, "secret", &secretobj);
890 	INSIST(algobj != NULL && secretobj != NULL);
891 
892 	algstr = cfg_obj_asstring(algobj);
893 	secretstr = cfg_obj_asstring(secretobj);
894 
895 	if (ns_config_getkeyalgorithm2(algstr, NULL,
896 				       &algtype, NULL) != ISC_R_SUCCESS) {
897 		cfg_obj_log(key, ns_g_lctx,
898 			    ISC_LOG_WARNING,
899 			    "unsupported algorithm '%s' in "
900 			    "key '%s' for use with command "
901 			    "channel",
902 			    algstr, keyid->keyname);
903 		goto cleanup;
904 	}
905 
906 	keyid->algorithm = algtype;
907 	isc_buffer_init(&b, secret, sizeof(secret));
908 	result = isc_base64_decodestring(secretstr, &b);
909 
910 	if (result != ISC_R_SUCCESS) {
911 		cfg_obj_log(key, ns_g_lctx, ISC_LOG_WARNING,
912 			    "secret for key '%s' on command channel: %s",
913 			    keyid->keyname, isc_result_totext(result));
914 		goto cleanup;
915 	}
916 
917 	keyid->secret.length = isc_buffer_usedlength(&b);
918 	keyid->secret.base = isc_mem_get(mctx,
919 					 keyid->secret.length);
920 	if (keyid->secret.base == NULL) {
921 		cfg_obj_log(key, ns_g_lctx, ISC_LOG_WARNING,
922 			   "couldn't register key '%s': "
923 			   "out of memory", keyid->keyname);
924 		CHECK(ISC_R_NOMEMORY);
925 	}
926 	memmove(keyid->secret.base, isc_buffer_base(&b),
927 		keyid->secret.length);
928 	ISC_LIST_APPEND(*keyids, keyid, link);
929 	keyid = NULL;
930 	result = ISC_R_SUCCESS;
931 
932   cleanup:
933 	if (keyid != NULL)
934 		free_controlkey(keyid, mctx);
935 	if (config != NULL)
936 		cfg_obj_destroy(pctx, &config);
937 	if (pctx != NULL)
938 		cfg_parser_destroy(&pctx);
939 	return (result);
940 }
941 
942 /*
943  * Ensures that both '*global_keylistp' and '*control_keylistp' are
944  * valid or both are NULL.
945  */
946 static void
get_key_info(const cfg_obj_t * config,const cfg_obj_t * control,const cfg_obj_t ** global_keylistp,const cfg_obj_t ** control_keylistp)947 get_key_info(const cfg_obj_t *config, const cfg_obj_t *control,
948 	     const cfg_obj_t **global_keylistp,
949 	     const cfg_obj_t **control_keylistp)
950 {
951 	isc_result_t result;
952 	const cfg_obj_t *control_keylist = NULL;
953 	const cfg_obj_t *global_keylist = NULL;
954 
955 	REQUIRE(global_keylistp != NULL && *global_keylistp == NULL);
956 	REQUIRE(control_keylistp != NULL && *control_keylistp == NULL);
957 
958 	control_keylist = cfg_tuple_get(control, "keys");
959 
960 	if (!cfg_obj_isvoid(control_keylist) &&
961 	    cfg_list_first(control_keylist) != NULL) {
962 		result = cfg_map_get(config, "key", &global_keylist);
963 
964 		if (result == ISC_R_SUCCESS) {
965 			*global_keylistp = global_keylist;
966 			*control_keylistp = control_keylist;
967 		}
968 	}
969 }
970 
971 static void
update_listener(ns_controls_t * cp,controllistener_t ** listenerp,const cfg_obj_t * control,const cfg_obj_t * config,isc_sockaddr_t * addr,cfg_aclconfctx_t * aclconfctx,const char * socktext,isc_sockettype_t type)972 update_listener(ns_controls_t *cp, controllistener_t **listenerp,
973 		const cfg_obj_t *control, const cfg_obj_t *config,
974 		isc_sockaddr_t *addr, cfg_aclconfctx_t *aclconfctx,
975 		const char *socktext, isc_sockettype_t type)
976 {
977 	controllistener_t *listener;
978 	const cfg_obj_t *allow;
979 	const cfg_obj_t *global_keylist = NULL;
980 	const cfg_obj_t *control_keylist = NULL;
981 	dns_acl_t *new_acl = NULL;
982 	controlkeylist_t keys;
983 	isc_result_t result = ISC_R_SUCCESS;
984 
985 	for (listener = ISC_LIST_HEAD(cp->listeners);
986 	     listener != NULL;
987 	     listener = ISC_LIST_NEXT(listener, link))
988 		if (isc_sockaddr_equal(addr, &listener->address))
989 			break;
990 
991 	if (listener == NULL) {
992 		*listenerp = NULL;
993 		return;
994 	}
995 
996 	/*
997 	 * There is already a listener for this sockaddr.
998 	 * Update the access list and key information.
999 	 *
1000 	 * First try to deal with the key situation.  There are a few
1001 	 * possibilities:
1002 	 *  (a)	It had an explicit keylist and still has an explicit keylist.
1003 	 *  (b)	It had an automagic key and now has an explicit keylist.
1004 	 *  (c)	It had an explicit keylist and now needs an automagic key.
1005 	 *  (d) It has an automagic key and still needs the automagic key.
1006 	 *
1007 	 * (c) and (d) are the annoying ones.  The caller needs to know
1008 	 * that it should use the automagic configuration for key information
1009 	 * in place of the named.conf configuration.
1010 	 *
1011 	 * XXXDCL There is one other hazard that has not been dealt with,
1012 	 * the problem that if a key change is being caused by a control
1013 	 * channel reload, then the response will be with the new key
1014 	 * and not able to be decrypted by the client.
1015 	 */
1016 	if (control != NULL)
1017 		get_key_info(config, control, &global_keylist,
1018 			     &control_keylist);
1019 
1020 	if (control_keylist != NULL) {
1021 		INSIST(global_keylist != NULL);
1022 
1023 		ISC_LIST_INIT(keys);
1024 		result = controlkeylist_fromcfg(control_keylist,
1025 						listener->mctx, &keys);
1026 		if (result == ISC_R_SUCCESS) {
1027 			free_controlkeylist(&listener->keys, listener->mctx);
1028 			listener->keys = keys;
1029 			register_keys(control, global_keylist, &listener->keys,
1030 				      listener->mctx, socktext);
1031 		}
1032 	} else {
1033 		free_controlkeylist(&listener->keys, listener->mctx);
1034 		result = get_rndckey(listener->mctx, &listener->keys);
1035 	}
1036 
1037 	if (result != ISC_R_SUCCESS && global_keylist != NULL) {
1038 		/*
1039 		 * This message might be a little misleading since the
1040 		 * "new keys" might in fact be identical to the old ones,
1041 		 * but tracking whether they are identical just for the
1042 		 * sake of avoiding this message would be too much trouble.
1043 		 */
1044 		if (control != NULL)
1045 			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
1046 				    "couldn't install new keys for "
1047 				    "command channel %s: %s",
1048 				    socktext, isc_result_totext(result));
1049 		else
1050 			isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
1051 				      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
1052 				      "couldn't install new keys for "
1053 				      "command channel %s: %s",
1054 				      socktext, isc_result_totext(result));
1055 	}
1056 
1057 	/*
1058 	 * Now, keep the old access list unless a new one can be made.
1059 	 */
1060 	if (control != NULL && type == isc_sockettype_tcp) {
1061 		allow = cfg_tuple_get(control, "allow");
1062 		result = cfg_acl_fromconfig(allow, config, ns_g_lctx,
1063 					    aclconfctx, listener->mctx, 0,
1064 					    &new_acl);
1065 	} else {
1066 		result = dns_acl_any(listener->mctx, &new_acl);
1067 	}
1068 
1069 	if (control != NULL) {
1070 		const cfg_obj_t *readonly;
1071 
1072 		readonly = cfg_tuple_get(control, "read-only");
1073 		if (!cfg_obj_isvoid(readonly))
1074 			listener->readonly = cfg_obj_asboolean(readonly);
1075 	}
1076 
1077 	if (result == ISC_R_SUCCESS) {
1078 		dns_acl_detach(&listener->acl);
1079 		dns_acl_attach(new_acl, &listener->acl);
1080 		dns_acl_detach(&new_acl);
1081 		/* XXXDCL say the old acl is still used? */
1082 	} else if (control != NULL)
1083 		cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
1084 			    "couldn't install new acl for "
1085 			    "command channel %s: %s",
1086 			    socktext, isc_result_totext(result));
1087 	else
1088 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
1089 			      NS_LOGMODULE_CONTROL, ISC_LOG_WARNING,
1090 			      "couldn't install new acl for "
1091 			      "command channel %s: %s",
1092 			      socktext, isc_result_totext(result));
1093 
1094 	if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) {
1095 		uint32_t perm, owner, group;
1096 		perm  = cfg_obj_asuint32(cfg_tuple_get(control, "perm"));
1097 		owner = cfg_obj_asuint32(cfg_tuple_get(control, "owner"));
1098 		group = cfg_obj_asuint32(cfg_tuple_get(control, "group"));
1099 		result = ISC_R_SUCCESS;
1100 		if (listener->perm != perm || listener->owner != owner ||
1101 		    listener->group != group)
1102 			result = isc_socket_permunix(&listener->address, perm,
1103 						     owner, group);
1104 		if (result == ISC_R_SUCCESS) {
1105 			listener->perm = perm;
1106 			listener->owner = owner;
1107 			listener->group = group;
1108 		} else if (control != NULL)
1109 			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
1110 				    "couldn't update ownership/permission for "
1111 				    "command channel %s", socktext);
1112 	}
1113 
1114 	*listenerp = listener;
1115 }
1116 
1117 static void
add_listener(ns_controls_t * cp,controllistener_t ** listenerp,const cfg_obj_t * control,const cfg_obj_t * config,isc_sockaddr_t * addr,cfg_aclconfctx_t * aclconfctx,const char * socktext,isc_sockettype_t type)1118 add_listener(ns_controls_t *cp, controllistener_t **listenerp,
1119 	     const cfg_obj_t *control, const cfg_obj_t *config,
1120 	     isc_sockaddr_t *addr, cfg_aclconfctx_t *aclconfctx,
1121 	     const char *socktext, isc_sockettype_t type)
1122 {
1123 	isc_mem_t *mctx = cp->server->mctx;
1124 	controllistener_t *listener;
1125 	const cfg_obj_t *allow;
1126 	const cfg_obj_t *global_keylist = NULL;
1127 	const cfg_obj_t *control_keylist = NULL;
1128 	dns_acl_t *new_acl = NULL;
1129 	isc_result_t result = ISC_R_SUCCESS;
1130 
1131 	listener = isc_mem_get(mctx, sizeof(*listener));
1132 	if (listener == NULL)
1133 		result = ISC_R_NOMEMORY;
1134 
1135 	if (result == ISC_R_SUCCESS) {
1136 		listener->mctx = NULL;
1137 		isc_mem_attach(mctx, &listener->mctx);
1138 		listener->controls = cp;
1139 		listener->task = cp->server->task;
1140 		listener->address = *addr;
1141 		listener->sock = NULL;
1142 		listener->listening = false;
1143 		listener->exiting = false;
1144 		listener->acl = NULL;
1145 		listener->type = type;
1146 		listener->perm = 0;
1147 		listener->owner = 0;
1148 		listener->group = 0;
1149 		listener->readonly = false;
1150 		ISC_LINK_INIT(listener, link);
1151 		ISC_LIST_INIT(listener->keys);
1152 		ISC_LIST_INIT(listener->connections);
1153 
1154 		/*
1155 		 * Make the acl.
1156 		 */
1157 		if (control != NULL && type == isc_sockettype_tcp) {
1158 			allow = cfg_tuple_get(control, "allow");
1159 			result = cfg_acl_fromconfig(allow, config, ns_g_lctx,
1160 						    aclconfctx, mctx, 0,
1161 						    &new_acl);
1162 		} else {
1163 			result = dns_acl_any(mctx, &new_acl);
1164 		}
1165 	}
1166 
1167 	if ((result == ISC_R_SUCCESS) && (control != NULL)) {
1168 		const cfg_obj_t *readonly;
1169 
1170 		readonly = cfg_tuple_get(control, "read-only");
1171 		if (!cfg_obj_isvoid(readonly))
1172 			listener->readonly = cfg_obj_asboolean(readonly);
1173 	}
1174 
1175 	if (result == ISC_R_SUCCESS) {
1176 		dns_acl_attach(new_acl, &listener->acl);
1177 		dns_acl_detach(&new_acl);
1178 
1179 		if (config != NULL)
1180 			get_key_info(config, control, &global_keylist,
1181 				     &control_keylist);
1182 
1183 		if (control_keylist != NULL) {
1184 			result = controlkeylist_fromcfg(control_keylist,
1185 							listener->mctx,
1186 							&listener->keys);
1187 			if (result == ISC_R_SUCCESS)
1188 				register_keys(control, global_keylist,
1189 					      &listener->keys,
1190 					      listener->mctx, socktext);
1191 		} else
1192 			result = get_rndckey(mctx, &listener->keys);
1193 
1194 		if (result != ISC_R_SUCCESS && control != NULL)
1195 			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
1196 				    "couldn't install keys for "
1197 				    "command channel %s: %s",
1198 				    socktext, isc_result_totext(result));
1199 	}
1200 
1201 	if (result == ISC_R_SUCCESS) {
1202 		int pf = isc_sockaddr_pf(&listener->address);
1203 		if ((pf == AF_INET && isc_net_probeipv4() != ISC_R_SUCCESS) ||
1204 #ifdef ISC_PLATFORM_HAVESYSUNH
1205 		    (pf == AF_UNIX && isc_net_probeunix() != ISC_R_SUCCESS) ||
1206 #endif
1207 		    (pf == AF_INET6 && isc_net_probeipv6() != ISC_R_SUCCESS))
1208 			result = ISC_R_FAMILYNOSUPPORT;
1209 	}
1210 
1211 	if (result == ISC_R_SUCCESS && type == isc_sockettype_unix)
1212 		isc_socket_cleanunix(&listener->address, false);
1213 
1214 	if (result == ISC_R_SUCCESS)
1215 		result = isc_socket_create(ns_g_socketmgr,
1216 					   isc_sockaddr_pf(&listener->address),
1217 					   type, &listener->sock);
1218 	if (result == ISC_R_SUCCESS)
1219 		isc_socket_setname(listener->sock, "control", NULL);
1220 
1221 #ifndef ISC_ALLOW_MAPPED
1222 	if (result == ISC_R_SUCCESS)
1223 		isc_socket_ipv6only(listener->sock, true);
1224 #endif
1225 
1226 	if (result == ISC_R_SUCCESS)
1227 		result = isc_socket_bind(listener->sock, &listener->address,
1228 					 ISC_SOCKET_REUSEADDRESS);
1229 
1230 	if (result == ISC_R_SUCCESS && type == isc_sockettype_unix) {
1231 		listener->perm = cfg_obj_asuint32(cfg_tuple_get(control,
1232 								"perm"));
1233 		listener->owner = cfg_obj_asuint32(cfg_tuple_get(control,
1234 								 "owner"));
1235 		listener->group = cfg_obj_asuint32(cfg_tuple_get(control,
1236 								 "group"));
1237 		result = isc_socket_permunix(&listener->address, listener->perm,
1238 					     listener->owner, listener->group);
1239 	}
1240 	if (result == ISC_R_SUCCESS)
1241 		result = control_listen(listener);
1242 
1243 	if (result == ISC_R_SUCCESS)
1244 		result = control_accept(listener);
1245 
1246 	if (result == ISC_R_SUCCESS) {
1247 		isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
1248 			      NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE,
1249 			      "command channel listening on %s", socktext);
1250 		*listenerp = listener;
1251 
1252 	} else {
1253 		if (listener != NULL) {
1254 			listener->exiting = true;
1255 			free_listener(listener);
1256 		}
1257 
1258 		if (control != NULL)
1259 			cfg_obj_log(control, ns_g_lctx, ISC_LOG_WARNING,
1260 				    "couldn't add command channel %s: %s",
1261 				    socktext, isc_result_totext(result));
1262 		else
1263 			isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
1264 				      NS_LOGMODULE_CONTROL, ISC_LOG_NOTICE,
1265 				      "couldn't add command channel %s: %s",
1266 				      socktext, isc_result_totext(result));
1267 
1268 		*listenerp = NULL;
1269 	}
1270 
1271 	/* XXXDCL return error results? fail hard? */
1272 }
1273 
1274 isc_result_t
ns_controls_configure(ns_controls_t * cp,const cfg_obj_t * config,cfg_aclconfctx_t * aclconfctx)1275 ns_controls_configure(ns_controls_t *cp, const cfg_obj_t *config,
1276 		      cfg_aclconfctx_t *aclconfctx)
1277 {
1278 	controllistener_t *listener;
1279 	controllistenerlist_t new_listeners;
1280 	const cfg_obj_t *controlslist = NULL;
1281 	const cfg_listelt_t *element, *element2;
1282 	char socktext[ISC_SOCKADDR_FORMATSIZE];
1283 
1284 	ISC_LIST_INIT(new_listeners);
1285 
1286 	/*
1287 	 * Get the list of named.conf 'controls' statements.
1288 	 */
1289 	(void)cfg_map_get(config, "controls", &controlslist);
1290 
1291 	/*
1292 	 * Run through the new control channel list, noting sockets that
1293 	 * are already being listened on and moving them to the new list.
1294 	 *
1295 	 * Identifying duplicate addr/port combinations is left to either
1296 	 * the underlying config code, or to the bind attempt getting an
1297 	 * address-in-use error.
1298 	 */
1299 	if (controlslist != NULL) {
1300 		for (element = cfg_list_first(controlslist);
1301 		     element != NULL;
1302 		     element = cfg_list_next(element)) {
1303 			const cfg_obj_t *controls;
1304 			const cfg_obj_t *inetcontrols = NULL;
1305 
1306 			controls = cfg_listelt_value(element);
1307 			(void)cfg_map_get(controls, "inet", &inetcontrols);
1308 			if (inetcontrols == NULL)
1309 				continue;
1310 
1311 			for (element2 = cfg_list_first(inetcontrols);
1312 			     element2 != NULL;
1313 			     element2 = cfg_list_next(element2)) {
1314 				const cfg_obj_t *control;
1315 				const cfg_obj_t *obj;
1316 				isc_sockaddr_t addr;
1317 
1318 				/*
1319 				 * The parser handles BIND 8 configuration file
1320 				 * syntax, so it allows unix phrases as well
1321 				 * inet phrases with no keys{} clause.
1322 				 */
1323 				control = cfg_listelt_value(element2);
1324 
1325 				obj = cfg_tuple_get(control, "address");
1326 				addr = *cfg_obj_assockaddr(obj);
1327 				if (isc_sockaddr_getport(&addr) == 0)
1328 					isc_sockaddr_setport(&addr,
1329 							     NS_CONTROL_PORT);
1330 
1331 				isc_sockaddr_format(&addr, socktext,
1332 						    sizeof(socktext));
1333 
1334 				isc_log_write(ns_g_lctx,
1335 					      NS_LOGCATEGORY_GENERAL,
1336 					      NS_LOGMODULE_CONTROL,
1337 					      ISC_LOG_DEBUG(9),
1338 					      "processing control channel %s",
1339 					      socktext);
1340 
1341 				update_listener(cp, &listener, control, config,
1342 						&addr, aclconfctx, socktext,
1343 						isc_sockettype_tcp);
1344 
1345 				if (listener != NULL)
1346 					/*
1347 					 * Remove the listener from the old
1348 					 * list, so it won't be shut down.
1349 					 */
1350 					ISC_LIST_UNLINK(cp->listeners,
1351 							listener, link);
1352 				else
1353 					/*
1354 					 * This is a new listener.
1355 					 */
1356 					add_listener(cp, &listener, control,
1357 						     config, &addr, aclconfctx,
1358 						     socktext,
1359 						     isc_sockettype_tcp);
1360 
1361 				if (listener != NULL)
1362 					ISC_LIST_APPEND(new_listeners,
1363 							listener, link);
1364 			}
1365 		}
1366 		for (element = cfg_list_first(controlslist);
1367 		     element != NULL;
1368 		     element = cfg_list_next(element)) {
1369 			const cfg_obj_t *controls;
1370 			const cfg_obj_t *unixcontrols = NULL;
1371 
1372 			controls = cfg_listelt_value(element);
1373 			(void)cfg_map_get(controls, "unix", &unixcontrols);
1374 			if (unixcontrols == NULL)
1375 				continue;
1376 
1377 			for (element2 = cfg_list_first(unixcontrols);
1378 			     element2 != NULL;
1379 			     element2 = cfg_list_next(element2)) {
1380 				const cfg_obj_t *control;
1381 				const cfg_obj_t *path;
1382 				isc_sockaddr_t addr;
1383 				isc_result_t result;
1384 
1385 				/*
1386 				 * The parser handles BIND 8 configuration file
1387 				 * syntax, so it allows unix phrases as well
1388 				 * inet phrases with no keys{} clause.
1389 				 */
1390 				control = cfg_listelt_value(element2);
1391 
1392 				path = cfg_tuple_get(control, "path");
1393 				result = isc_sockaddr_frompath(&addr,
1394 						      cfg_obj_asstring(path));
1395 				if (result != ISC_R_SUCCESS) {
1396 					isc_log_write(ns_g_lctx,
1397 					      NS_LOGCATEGORY_GENERAL,
1398 					      NS_LOGMODULE_CONTROL,
1399 					      ISC_LOG_DEBUG(9),
1400 					      "control channel '%s': %s",
1401 					      cfg_obj_asstring(path),
1402 					      isc_result_totext(result));
1403 					continue;
1404 				}
1405 
1406 				isc_log_write(ns_g_lctx,
1407 					      NS_LOGCATEGORY_GENERAL,
1408 					      NS_LOGMODULE_CONTROL,
1409 					      ISC_LOG_DEBUG(9),
1410 					      "processing control channel '%s'",
1411 					      cfg_obj_asstring(path));
1412 
1413 				update_listener(cp, &listener, control, config,
1414 						&addr, aclconfctx,
1415 						cfg_obj_asstring(path),
1416 						isc_sockettype_unix);
1417 
1418 				if (listener != NULL)
1419 					/*
1420 					 * Remove the listener from the old
1421 					 * list, so it won't be shut down.
1422 					 */
1423 					ISC_LIST_UNLINK(cp->listeners,
1424 							listener, link);
1425 				else
1426 					/*
1427 					 * This is a new listener.
1428 					 */
1429 					add_listener(cp, &listener, control,
1430 						     config, &addr, aclconfctx,
1431 						     cfg_obj_asstring(path),
1432 						     isc_sockettype_unix);
1433 
1434 				if (listener != NULL)
1435 					ISC_LIST_APPEND(new_listeners,
1436 							listener, link);
1437 			}
1438 		}
1439 	} else {
1440 		int i;
1441 
1442 		for (i = 0; i < 2; i++) {
1443 			isc_sockaddr_t addr;
1444 
1445 			if (i == 0) {
1446 				struct in_addr localhost;
1447 
1448 				if (isc_net_probeipv4() != ISC_R_SUCCESS)
1449 					continue;
1450 				localhost.s_addr = htonl(INADDR_LOOPBACK);
1451 				isc_sockaddr_fromin(&addr, &localhost, 0);
1452 			} else {
1453 				if (isc_net_probeipv6() != ISC_R_SUCCESS)
1454 					continue;
1455 				isc_sockaddr_fromin6(&addr,
1456 						     &in6addr_loopback, 0);
1457 			}
1458 			isc_sockaddr_setport(&addr, NS_CONTROL_PORT);
1459 
1460 			isc_sockaddr_format(&addr, socktext, sizeof(socktext));
1461 
1462 			update_listener(cp, &listener, NULL, NULL,
1463 					&addr, NULL, socktext,
1464 					isc_sockettype_tcp);
1465 
1466 			if (listener != NULL)
1467 				/*
1468 				 * Remove the listener from the old
1469 				 * list, so it won't be shut down.
1470 				 */
1471 				ISC_LIST_UNLINK(cp->listeners,
1472 						listener, link);
1473 			else
1474 				/*
1475 				 * This is a new listener.
1476 				 */
1477 				add_listener(cp, &listener, NULL, NULL,
1478 					     &addr, NULL, socktext,
1479 					     isc_sockettype_tcp);
1480 
1481 			if (listener != NULL)
1482 				ISC_LIST_APPEND(new_listeners,
1483 						listener, link);
1484 		}
1485 	}
1486 
1487 	/*
1488 	 * ns_control_shutdown() will stop whatever is on the global
1489 	 * listeners list, which currently only has whatever sockaddrs
1490 	 * were in the previous configuration (if any) that do not
1491 	 * remain in the current configuration.
1492 	 */
1493 	controls_shutdown(cp);
1494 
1495 	/*
1496 	 * Put all of the valid listeners on the listeners list.
1497 	 * Anything already on listeners in the process of shutting
1498 	 * down will be taken care of by listen_done().
1499 	 */
1500 	ISC_LIST_APPENDLIST(cp->listeners, new_listeners, link);
1501 	return (ISC_R_SUCCESS);
1502 }
1503 
1504 isc_result_t
ns_controls_create(ns_server_t * server,ns_controls_t ** ctrlsp)1505 ns_controls_create(ns_server_t *server, ns_controls_t **ctrlsp) {
1506 	isc_mem_t *mctx = server->mctx;
1507 	isc_result_t result;
1508 	ns_controls_t *controls = isc_mem_get(mctx, sizeof(*controls));
1509 
1510 	if (controls == NULL) {
1511 		return (ISC_R_NOMEMORY);
1512 	}
1513 
1514 	*controls = (ns_controls_t){
1515 		.server = server,
1516 	};
1517 
1518 	ISC_LIST_INIT(controls->listeners);
1519 
1520 	result = isc_mutex_init(&controls->symtab_lock);
1521 	if (result != ISC_R_SUCCESS) {
1522 		isc_mem_put(server->mctx, controls, sizeof(*controls));
1523 		return (result);
1524 	}
1525 
1526 	LOCK(&controls->symtab_lock);
1527 	result = isccc_cc_createsymtab(&controls->symtab);
1528 	UNLOCK(&controls->symtab_lock);
1529 
1530 	if (result != ISC_R_SUCCESS) {
1531 		isc_mutex_destroy(&controls->symtab_lock);
1532 		isc_mem_put(server->mctx, controls, sizeof(*controls));
1533 		return (result);
1534 	}
1535 	*ctrlsp = controls;
1536 	return (ISC_R_SUCCESS);
1537 }
1538 
1539 void
ns_controls_destroy(ns_controls_t ** ctrlsp)1540 ns_controls_destroy(ns_controls_t **ctrlsp) {
1541 	ns_controls_t *controls = *ctrlsp;
1542 
1543 	REQUIRE(ISC_LIST_EMPTY(controls->listeners));
1544 
1545 	LOCK(&controls->symtab_lock);
1546 	isccc_symtab_destroy(&controls->symtab);
1547 	UNLOCK(&controls->symtab_lock);
1548 	isc_mutex_destroy(&controls->symtab_lock);
1549 	isc_mem_put(controls->server->mctx, controls, sizeof(*controls));
1550 	*ctrlsp = NULL;
1551 }
1552