1 /*
2 * Copyright (C) 2004-2009, 2012, 2015 Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 2000-2003 Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 /* $Id: lwresd.c,v 1.60 2009/09/02 23:48:01 tbox Exp $ */
19
20 /*! \file
21 * \brief
22 * Main program for the Lightweight Resolver Daemon.
23 *
24 * To paraphrase the old saying about X11, "It's not a lightweight deamon
25 * for resolvers, it's a deamon for lightweight resolvers".
26 */
27
28 #include <config.h>
29
30 #include <stdlib.h>
31 #include <string.h>
32
33 #include <isc/list.h>
34 #include <isc/magic.h>
35 #include <isc/mem.h>
36 #include <isc/once.h>
37 #include <isc/print.h>
38 #include <isc/socket.h>
39 #include <isc/task.h>
40 #include <isc/util.h>
41
42 #include <isccfg/namedconf.h>
43
44 #include <dns/log.h>
45 #include <dns/result.h>
46 #include <dns/view.h>
47
48 #include <named/config.h>
49 #include <named/globals.h>
50 #include <named/log.h>
51 #include <named/lwaddr.h>
52 #include <named/lwresd.h>
53 #include <named/lwdclient.h>
54 #include <named/lwsearch.h>
55 #include <named/server.h>
56
57 #define LWRESD_MAGIC ISC_MAGIC('L', 'W', 'R', 'D')
58 #define VALID_LWRESD(l) ISC_MAGIC_VALID(l, LWRESD_MAGIC)
59
60 #define LWRESLISTENER_MAGIC ISC_MAGIC('L', 'W', 'R', 'L')
61 #define VALID_LWRESLISTENER(l) ISC_MAGIC_VALID(l, LWRESLISTENER_MAGIC)
62
63 /*!
64 * The total number of clients we can handle will be NTASKS * NRECVS.
65 */
66 #define NTASKS 2 /*%< tasks to create to handle lwres queries */
67 #define NRECVS 2 /*%< max clients per task */
68
69 typedef ISC_LIST(ns_lwreslistener_t) ns_lwreslistenerlist_t;
70
71 static ns_lwreslistenerlist_t listeners;
72 static isc_mutex_t listeners_lock;
73 static isc_once_t once = ISC_ONCE_INIT;
74
75
76 static void
initialize_mutex(void)77 initialize_mutex(void) {
78 RUNTIME_CHECK(isc_mutex_init(&listeners_lock) == ISC_R_SUCCESS);
79 }
80
81
82 /*%
83 * Wrappers around our memory management stuff, for the lwres functions.
84 */
85 void *
ns__lwresd_memalloc(void * arg,size_t size)86 ns__lwresd_memalloc(void *arg, size_t size) {
87 return (isc_mem_get(arg, size));
88 }
89
90 void
ns__lwresd_memfree(void * arg,void * mem,size_t size)91 ns__lwresd_memfree(void *arg, void *mem, size_t size) {
92 isc_mem_put(arg, mem, size);
93 }
94
95
96 #define CHECK(op) \
97 do { result = (op); \
98 if (result != ISC_R_SUCCESS) goto cleanup; \
99 } while (0)
100
101 static isc_result_t
buffer_putstr(isc_buffer_t * b,const char * s)102 buffer_putstr(isc_buffer_t *b, const char *s) {
103 unsigned int len = strlen(s);
104 if (isc_buffer_availablelength(b) <= len)
105 return (ISC_R_NOSPACE);
106 isc_buffer_putmem(b, (const unsigned char *)s, len);
107 return (ISC_R_SUCCESS);
108 }
109
110 /*
111 * Convert a resolv.conf file into a config structure.
112 */
113 isc_result_t
ns_lwresd_parseeresolvconf(isc_mem_t * mctx,cfg_parser_t * pctx,cfg_obj_t ** configp)114 ns_lwresd_parseeresolvconf(isc_mem_t *mctx, cfg_parser_t *pctx,
115 cfg_obj_t **configp)
116 {
117 char text[4096];
118 char str[16];
119 isc_buffer_t b;
120 lwres_context_t *lwctx = NULL;
121 lwres_conf_t *lwc = NULL;
122 isc_sockaddr_t sa;
123 isc_netaddr_t na;
124 int i;
125 isc_result_t result;
126 lwres_result_t lwresult;
127
128 lwctx = NULL;
129 lwresult = lwres_context_create(&lwctx, mctx, ns__lwresd_memalloc,
130 ns__lwresd_memfree,
131 LWRES_CONTEXT_SERVERMODE);
132 if (lwresult != LWRES_R_SUCCESS) {
133 result = ISC_R_NOMEMORY;
134 goto cleanup;
135 }
136
137 lwresult = lwres_conf_parse(lwctx, lwresd_g_resolvconffile);
138 if (lwresult != LWRES_R_SUCCESS) {
139 result = DNS_R_SYNTAX;
140 goto cleanup;
141 }
142
143 lwc = lwres_conf_get(lwctx);
144 INSIST(lwc != NULL);
145
146 isc_buffer_init(&b, text, sizeof(text));
147
148 CHECK(buffer_putstr(&b, "options {\n"));
149
150 /*
151 * Build the list of forwarders.
152 */
153 if (lwc->nsnext > 0) {
154 CHECK(buffer_putstr(&b, "\tforwarders {\n"));
155
156 for (i = 0; i < lwc->nsnext; i++) {
157 CHECK(lwaddr_sockaddr_fromlwresaddr(
158 &sa,
159 &lwc->nameservers[i],
160 ns_g_port));
161 isc_netaddr_fromsockaddr(&na, &sa);
162 CHECK(buffer_putstr(&b, "\t\t"));
163 CHECK(isc_netaddr_totext(&na, &b));
164 CHECK(buffer_putstr(&b, ";\n"));
165 }
166 CHECK(buffer_putstr(&b, "\t};\n"));
167 }
168
169 /*
170 * Build the sortlist
171 */
172 if (lwc->sortlistnxt > 0) {
173 CHECK(buffer_putstr(&b, "\tsortlist {\n"));
174 CHECK(buffer_putstr(&b, "\t\t{\n"));
175 CHECK(buffer_putstr(&b, "\t\t\tany;\n"));
176 CHECK(buffer_putstr(&b, "\t\t\t{\n"));
177 for (i = 0; i < lwc->sortlistnxt; i++) {
178 lwres_addr_t *lwaddr = &lwc->sortlist[i].addr;
179 lwres_addr_t *lwmask = &lwc->sortlist[i].mask;
180 unsigned int mask;
181
182 CHECK(lwaddr_sockaddr_fromlwresaddr(&sa, lwmask, 0));
183 isc_netaddr_fromsockaddr(&na, &sa);
184 result = isc_netaddr_masktoprefixlen(&na, &mask);
185 if (result != ISC_R_SUCCESS) {
186 char addrtext[ISC_NETADDR_FORMATSIZE];
187 isc_netaddr_format(&na, addrtext,
188 sizeof(addrtext));
189 isc_log_write(ns_g_lctx,
190 NS_LOGCATEGORY_GENERAL,
191 NS_LOGMODULE_LWRESD,
192 ISC_LOG_ERROR,
193 "processing sortlist: '%s' is "
194 "not a valid netmask",
195 addrtext);
196 goto cleanup;
197 }
198
199 CHECK(lwaddr_sockaddr_fromlwresaddr(&sa, lwaddr, 0));
200 isc_netaddr_fromsockaddr(&na, &sa);
201
202 CHECK(buffer_putstr(&b, "\t\t\t\t"));
203 CHECK(isc_netaddr_totext(&na, &b));
204 snprintf(str, sizeof(str), "%u", mask);
205 CHECK(buffer_putstr(&b, "/"));
206 CHECK(buffer_putstr(&b, str));
207 CHECK(buffer_putstr(&b, ";\n"));
208 }
209 CHECK(buffer_putstr(&b, "\t\t\t};\n"));
210 CHECK(buffer_putstr(&b, "\t\t};\n"));
211 CHECK(buffer_putstr(&b, "\t};\n"));
212 }
213
214 CHECK(buffer_putstr(&b, "};\n\n"));
215
216 CHECK(buffer_putstr(&b, "lwres {\n"));
217
218 /*
219 * Build the search path
220 */
221 if (lwc->searchnxt > 0) {
222 if (lwc->searchnxt > 0) {
223 CHECK(buffer_putstr(&b, "\tsearch {\n"));
224 for (i = 0; i < lwc->searchnxt; i++) {
225 CHECK(buffer_putstr(&b, "\t\t\""));
226 CHECK(buffer_putstr(&b, lwc->search[i]));
227 CHECK(buffer_putstr(&b, "\";\n"));
228 }
229 CHECK(buffer_putstr(&b, "\t};\n"));
230 }
231 }
232
233 /*
234 * Build the ndots line
235 */
236 if (lwc->ndots != 1) {
237 CHECK(buffer_putstr(&b, "\tndots "));
238 snprintf(str, sizeof(str), "%u", lwc->ndots);
239 CHECK(buffer_putstr(&b, str));
240 CHECK(buffer_putstr(&b, ";\n"));
241 }
242
243 /*
244 * Build the listen-on line
245 */
246 if (lwc->lwnext > 0) {
247 CHECK(buffer_putstr(&b, "\tlisten-on {\n"));
248
249 for (i = 0; i < lwc->lwnext; i++) {
250 CHECK(lwaddr_sockaddr_fromlwresaddr(&sa,
251 &lwc->lwservers[i],
252 0));
253 isc_netaddr_fromsockaddr(&na, &sa);
254 CHECK(buffer_putstr(&b, "\t\t"));
255 CHECK(isc_netaddr_totext(&na, &b));
256 CHECK(buffer_putstr(&b, ";\n"));
257 }
258 CHECK(buffer_putstr(&b, "\t};\n"));
259 }
260
261 CHECK(buffer_putstr(&b, "};\n"));
262
263 #if 0
264 printf("%.*s\n",
265 (int)isc_buffer_usedlength(&b),
266 (char *)isc_buffer_base(&b));
267 #endif
268
269 lwres_conf_clear(lwctx);
270 lwres_context_destroy(&lwctx);
271
272 return (cfg_parse_buffer(pctx, &b, &cfg_type_namedconf, configp));
273
274 cleanup:
275
276 if (lwctx != NULL) {
277 lwres_conf_clear(lwctx);
278 lwres_context_destroy(&lwctx);
279 }
280
281 return (result);
282 }
283
284
285 /*
286 * Handle lwresd manager objects
287 */
288 isc_result_t
ns_lwdmanager_create(isc_mem_t * mctx,const cfg_obj_t * lwres,ns_lwresd_t ** lwresdp)289 ns_lwdmanager_create(isc_mem_t *mctx, const cfg_obj_t *lwres,
290 ns_lwresd_t **lwresdp)
291 {
292 ns_lwresd_t *lwresd;
293 const char *vname;
294 dns_rdataclass_t vclass;
295 const cfg_obj_t *obj, *viewobj, *searchobj;
296 const cfg_listelt_t *element;
297 isc_result_t result;
298
299 INSIST(lwresdp != NULL && *lwresdp == NULL);
300
301 lwresd = isc_mem_get(mctx, sizeof(ns_lwresd_t));
302 if (lwresd == NULL)
303 return (ISC_R_NOMEMORY);
304
305 lwresd->mctx = NULL;
306 isc_mem_attach(mctx, &lwresd->mctx);
307 lwresd->view = NULL;
308 lwresd->search = NULL;
309 lwresd->refs = 1;
310
311 obj = NULL;
312 (void)cfg_map_get(lwres, "ndots", &obj);
313 if (obj != NULL)
314 lwresd->ndots = cfg_obj_asuint32(obj);
315 else
316 lwresd->ndots = 1;
317
318 RUNTIME_CHECK(isc_mutex_init(&lwresd->lock) == ISC_R_SUCCESS);
319
320 lwresd->shutting_down = ISC_FALSE;
321
322 viewobj = NULL;
323 (void)cfg_map_get(lwres, "view", &viewobj);
324 if (viewobj != NULL) {
325 vname = cfg_obj_asstring(cfg_tuple_get(viewobj, "name"));
326 obj = cfg_tuple_get(viewobj, "class");
327 result = ns_config_getclass(obj, dns_rdataclass_in, &vclass);
328 if (result != ISC_R_SUCCESS)
329 goto fail;
330 } else {
331 vname = "_default";
332 vclass = dns_rdataclass_in;
333 }
334
335 result = dns_viewlist_find(&ns_g_server->viewlist, vname, vclass,
336 &lwresd->view);
337 if (result != ISC_R_SUCCESS) {
338 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
339 NS_LOGMODULE_LWRESD, ISC_LOG_WARNING,
340 "couldn't find view %s", vname);
341 goto fail;
342 }
343
344 searchobj = NULL;
345 (void)cfg_map_get(lwres, "search", &searchobj);
346 if (searchobj != NULL) {
347 lwresd->search = NULL;
348 result = ns_lwsearchlist_create(lwresd->mctx,
349 &lwresd->search);
350 if (result != ISC_R_SUCCESS) {
351 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
352 NS_LOGMODULE_LWRESD, ISC_LOG_WARNING,
353 "couldn't create searchlist");
354 goto fail;
355 }
356 for (element = cfg_list_first(searchobj);
357 element != NULL;
358 element = cfg_list_next(element))
359 {
360 const cfg_obj_t *search;
361 const char *searchstr;
362 isc_buffer_t namebuf;
363 dns_fixedname_t fname;
364 dns_name_t *name;
365
366 search = cfg_listelt_value(element);
367 searchstr = cfg_obj_asstring(search);
368
369 dns_fixedname_init(&fname);
370 name = dns_fixedname_name(&fname);
371 isc_buffer_constinit(&namebuf, searchstr,
372 strlen(searchstr));
373 isc_buffer_add(&namebuf, strlen(searchstr));
374 result = dns_name_fromtext(name, &namebuf,
375 dns_rootname, 0, NULL);
376 if (result != ISC_R_SUCCESS) {
377 isc_log_write(ns_g_lctx,
378 NS_LOGCATEGORY_GENERAL,
379 NS_LOGMODULE_LWRESD,
380 ISC_LOG_WARNING,
381 "invalid name %s in searchlist",
382 searchstr);
383 continue;
384 }
385
386 result = ns_lwsearchlist_append(lwresd->search, name);
387 if (result != ISC_R_SUCCESS) {
388 isc_log_write(ns_g_lctx,
389 NS_LOGCATEGORY_GENERAL,
390 NS_LOGMODULE_LWRESD,
391 ISC_LOG_WARNING,
392 "couldn't update searchlist");
393 goto fail;
394 }
395 }
396 }
397
398 lwresd->magic = LWRESD_MAGIC;
399
400 *lwresdp = lwresd;
401 return (ISC_R_SUCCESS);
402
403 fail:
404 if (lwresd->view != NULL)
405 dns_view_detach(&lwresd->view);
406 if (lwresd->search != NULL)
407 ns_lwsearchlist_detach(&lwresd->search);
408 if (lwresd->mctx != NULL)
409 isc_mem_detach(&lwresd->mctx);
410 isc_mem_put(mctx, lwresd, sizeof(ns_lwresd_t));
411 return (result);
412 }
413
414 void
ns_lwdmanager_attach(ns_lwresd_t * source,ns_lwresd_t ** targetp)415 ns_lwdmanager_attach(ns_lwresd_t *source, ns_lwresd_t **targetp) {
416 INSIST(VALID_LWRESD(source));
417 INSIST(targetp != NULL && *targetp == NULL);
418
419 LOCK(&source->lock);
420 source->refs++;
421 UNLOCK(&source->lock);
422
423 *targetp = source;
424 }
425
426 void
ns_lwdmanager_detach(ns_lwresd_t ** lwresdp)427 ns_lwdmanager_detach(ns_lwresd_t **lwresdp) {
428 ns_lwresd_t *lwresd;
429 isc_mem_t *mctx;
430 isc_boolean_t done = ISC_FALSE;
431
432 INSIST(lwresdp != NULL && *lwresdp != NULL);
433 INSIST(VALID_LWRESD(*lwresdp));
434
435 lwresd = *lwresdp;
436 *lwresdp = NULL;
437
438 LOCK(&lwresd->lock);
439 INSIST(lwresd->refs > 0);
440 lwresd->refs--;
441 if (lwresd->refs == 0)
442 done = ISC_TRUE;
443 UNLOCK(&lwresd->lock);
444
445 if (!done)
446 return;
447
448 dns_view_detach(&lwresd->view);
449 if (lwresd->search != NULL)
450 ns_lwsearchlist_detach(&lwresd->search);
451 mctx = lwresd->mctx;
452 lwresd->magic = 0;
453 isc_mem_put(mctx, lwresd, sizeof(*lwresd));
454 isc_mem_detach(&mctx);
455 }
456
457
458 /*
459 * Handle listener objects
460 */
461 void
ns_lwreslistener_attach(ns_lwreslistener_t * source,ns_lwreslistener_t ** targetp)462 ns_lwreslistener_attach(ns_lwreslistener_t *source,
463 ns_lwreslistener_t **targetp)
464 {
465 INSIST(VALID_LWRESLISTENER(source));
466 INSIST(targetp != NULL && *targetp == NULL);
467
468 LOCK(&source->lock);
469 source->refs++;
470 UNLOCK(&source->lock);
471
472 *targetp = source;
473 }
474
475 void
ns_lwreslistener_detach(ns_lwreslistener_t ** listenerp)476 ns_lwreslistener_detach(ns_lwreslistener_t **listenerp) {
477 ns_lwreslistener_t *listener;
478 isc_mem_t *mctx;
479 isc_boolean_t done = ISC_FALSE;
480
481 INSIST(listenerp != NULL && *listenerp != NULL);
482 INSIST(VALID_LWRESLISTENER(*listenerp));
483
484 listener = *listenerp;
485
486 LOCK(&listener->lock);
487 INSIST(listener->refs > 0);
488 listener->refs--;
489 if (listener->refs == 0)
490 done = ISC_TRUE;
491 UNLOCK(&listener->lock);
492
493 if (!done)
494 return;
495
496 if (listener->manager != NULL)
497 ns_lwdmanager_detach(&listener->manager);
498
499 if (listener->sock != NULL)
500 isc_socket_detach(&listener->sock);
501
502 listener->magic = 0;
503 mctx = listener->mctx;
504 isc_mem_put(mctx, listener, sizeof(*listener));
505 isc_mem_detach(&mctx);
506 listenerp = NULL;
507 }
508
509 static isc_result_t
listener_create(isc_mem_t * mctx,ns_lwresd_t * lwresd,ns_lwreslistener_t ** listenerp)510 listener_create(isc_mem_t *mctx, ns_lwresd_t *lwresd,
511 ns_lwreslistener_t **listenerp)
512 {
513 ns_lwreslistener_t *listener;
514 isc_result_t result;
515
516 REQUIRE(listenerp != NULL && *listenerp == NULL);
517
518 listener = isc_mem_get(mctx, sizeof(ns_lwreslistener_t));
519 if (listener == NULL)
520 return (ISC_R_NOMEMORY);
521
522 result = isc_mutex_init(&listener->lock);
523 if (result != ISC_R_SUCCESS) {
524 isc_mem_put(mctx, listener, sizeof(ns_lwreslistener_t));
525 return (result);
526 }
527
528 listener->magic = LWRESLISTENER_MAGIC;
529 listener->refs = 1;
530
531 listener->sock = NULL;
532
533 listener->manager = NULL;
534 ns_lwdmanager_attach(lwresd, &listener->manager);
535
536 listener->mctx = NULL;
537 isc_mem_attach(mctx, &listener->mctx);
538
539 ISC_LINK_INIT(listener, link);
540 ISC_LIST_INIT(listener->cmgrs);
541
542 *listenerp = listener;
543 return (ISC_R_SUCCESS);
544 }
545
546 static isc_result_t
listener_bind(ns_lwreslistener_t * listener,isc_sockaddr_t * address)547 listener_bind(ns_lwreslistener_t *listener, isc_sockaddr_t *address) {
548 isc_socket_t *sock = NULL;
549 isc_result_t result = ISC_R_SUCCESS;
550 int pf;
551
552 pf = isc_sockaddr_pf(address);
553 if ((pf == AF_INET && isc_net_probeipv4() != ISC_R_SUCCESS) ||
554 (pf == AF_INET6 && isc_net_probeipv6() != ISC_R_SUCCESS))
555 return (ISC_R_FAMILYNOSUPPORT);
556
557 listener->address = *address;
558
559 if (isc_sockaddr_getport(&listener->address) == 0) {
560 in_port_t port;
561 port = lwresd_g_listenport;
562 if (port == 0)
563 port = LWRES_UDP_PORT;
564 isc_sockaddr_setport(&listener->address, port);
565 }
566
567 sock = NULL;
568 result = isc_socket_create(ns_g_socketmgr, pf,
569 isc_sockettype_udp, &sock);
570 if (result != ISC_R_SUCCESS) {
571 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
572 NS_LOGMODULE_LWRESD, ISC_LOG_WARNING,
573 "failed to create lwres socket: %s",
574 isc_result_totext(result));
575 return (result);
576 }
577
578 result = isc_socket_bind(sock, &listener->address,
579 ISC_SOCKET_REUSEADDRESS);
580 if (result != ISC_R_SUCCESS) {
581 char socktext[ISC_SOCKADDR_FORMATSIZE];
582 isc_sockaddr_format(&listener->address, socktext,
583 sizeof(socktext));
584 isc_socket_detach(&sock);
585 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
586 NS_LOGMODULE_LWRESD, ISC_LOG_WARNING,
587 "failed to add lwres socket: %s: %s",
588 socktext, isc_result_totext(result));
589 return (result);
590 }
591 listener->sock = sock;
592 return (ISC_R_SUCCESS);
593 }
594
595 static void
listener_copysock(ns_lwreslistener_t * oldlistener,ns_lwreslistener_t * newlistener)596 listener_copysock(ns_lwreslistener_t *oldlistener,
597 ns_lwreslistener_t *newlistener)
598 {
599 newlistener->address = oldlistener->address;
600 isc_socket_attach(oldlistener->sock, &newlistener->sock);
601 }
602
603 static isc_result_t
listener_startclients(ns_lwreslistener_t * listener)604 listener_startclients(ns_lwreslistener_t *listener) {
605 ns_lwdclientmgr_t *cm, *next;
606 unsigned int i;
607 isc_result_t result;
608
609 /*
610 * Create the client managers.
611 */
612 result = ISC_R_SUCCESS;
613 for (i = 0; i < NTASKS && result == ISC_R_SUCCESS; i++)
614 result = ns_lwdclientmgr_create(listener, NRECVS,
615 ns_g_taskmgr);
616
617 /*
618 * Ensure that we have created at least one.
619 */
620 if (ISC_LIST_EMPTY(listener->cmgrs))
621 return (result);
622
623 /*
624 * Walk the list of clients and start each one up.
625 */
626 LOCK(&listener->lock);
627 cm = ISC_LIST_HEAD(listener->cmgrs);
628 while (cm != NULL) {
629 next = ISC_LIST_NEXT(cm, link);
630 result = ns_lwdclient_startrecv(cm);
631 if (result != ISC_R_SUCCESS)
632 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
633 NS_LOGMODULE_LWRESD, ISC_LOG_ERROR,
634 "could not start lwres "
635 "client handler: %s",
636 isc_result_totext(result));
637 cm = next;
638 }
639 UNLOCK(&listener->lock);
640
641 return (ISC_R_SUCCESS);
642 }
643
644 static void
listener_shutdown(ns_lwreslistener_t * listener)645 listener_shutdown(ns_lwreslistener_t *listener) {
646 ns_lwdclientmgr_t *cm;
647
648 cm = ISC_LIST_HEAD(listener->cmgrs);
649 while (cm != NULL) {
650 isc_task_shutdown(cm->task);
651 cm = ISC_LIST_NEXT(cm, link);
652 }
653 }
654
655 static isc_result_t
find_listener(isc_sockaddr_t * address,ns_lwreslistener_t ** listenerp)656 find_listener(isc_sockaddr_t *address, ns_lwreslistener_t **listenerp) {
657 ns_lwreslistener_t *listener;
658
659 INSIST(listenerp != NULL && *listenerp == NULL);
660
661 for (listener = ISC_LIST_HEAD(listeners);
662 listener != NULL;
663 listener = ISC_LIST_NEXT(listener, link))
664 {
665 if (!isc_sockaddr_equal(address, &listener->address))
666 continue;
667 *listenerp = listener;
668 return (ISC_R_SUCCESS);
669 }
670 return (ISC_R_NOTFOUND);
671 }
672
673 void
ns_lwreslistener_unlinkcm(ns_lwreslistener_t * listener,ns_lwdclientmgr_t * cm)674 ns_lwreslistener_unlinkcm(ns_lwreslistener_t *listener, ns_lwdclientmgr_t *cm)
675 {
676 REQUIRE(VALID_LWRESLISTENER(listener));
677
678 LOCK(&listener->lock);
679 ISC_LIST_UNLINK(listener->cmgrs, cm, link);
680 UNLOCK(&listener->lock);
681 }
682
683 void
ns_lwreslistener_linkcm(ns_lwreslistener_t * listener,ns_lwdclientmgr_t * cm)684 ns_lwreslistener_linkcm(ns_lwreslistener_t *listener, ns_lwdclientmgr_t *cm) {
685 REQUIRE(VALID_LWRESLISTENER(listener));
686
687 /*
688 * This does no locking, since it's called early enough that locking
689 * isn't needed.
690 */
691 ISC_LIST_APPEND(listener->cmgrs, cm, link);
692 }
693
694 static isc_result_t
configure_listener(isc_sockaddr_t * address,ns_lwresd_t * lwresd,isc_mem_t * mctx,ns_lwreslistenerlist_t * newlisteners)695 configure_listener(isc_sockaddr_t *address, ns_lwresd_t *lwresd,
696 isc_mem_t *mctx, ns_lwreslistenerlist_t *newlisteners)
697 {
698 ns_lwreslistener_t *listener, *oldlistener = NULL;
699 char socktext[ISC_SOCKADDR_FORMATSIZE];
700 isc_result_t result;
701
702 (void)find_listener(address, &oldlistener);
703 listener = NULL;
704 result = listener_create(mctx, lwresd, &listener);
705 if (result != ISC_R_SUCCESS) {
706 isc_sockaddr_format(address, socktext, sizeof(socktext));
707 isc_log_write(ns_g_lctx, ISC_LOGCATEGORY_GENERAL,
708 NS_LOGMODULE_LWRESD, ISC_LOG_WARNING,
709 "lwres failed to configure %s: %s",
710 socktext, isc_result_totext(result));
711 return (result);
712 }
713
714 /*
715 * If there's already a listener, don't rebind the socket.
716 */
717 if (oldlistener == NULL) {
718 result = listener_bind(listener, address);
719 if (result != ISC_R_SUCCESS) {
720 ns_lwreslistener_detach(&listener);
721 return (ISC_R_SUCCESS);
722 }
723 } else
724 listener_copysock(oldlistener, listener);
725
726 result = listener_startclients(listener);
727 if (result != ISC_R_SUCCESS) {
728 isc_sockaddr_format(address, socktext, sizeof(socktext));
729 isc_log_write(ns_g_lctx, ISC_LOGCATEGORY_GENERAL,
730 NS_LOGMODULE_LWRESD, ISC_LOG_WARNING,
731 "lwres: failed to start %s: %s", socktext,
732 isc_result_totext(result));
733 ns_lwreslistener_detach(&listener);
734 return (ISC_R_SUCCESS);
735 }
736
737 if (oldlistener != NULL) {
738 /*
739 * Remove the old listener from the old list and shut it down.
740 */
741 ISC_LIST_UNLINK(listeners, oldlistener, link);
742 listener_shutdown(oldlistener);
743 ns_lwreslistener_detach(&oldlistener);
744 } else {
745 isc_sockaddr_format(address, socktext, sizeof(socktext));
746 isc_log_write(ns_g_lctx, ISC_LOGCATEGORY_GENERAL,
747 NS_LOGMODULE_LWRESD, ISC_LOG_NOTICE,
748 "lwres listening on %s", socktext);
749 }
750
751 ISC_LIST_APPEND(*newlisteners, listener, link);
752 return (result);
753 }
754
755 isc_result_t
ns_lwresd_configure(isc_mem_t * mctx,const cfg_obj_t * config)756 ns_lwresd_configure(isc_mem_t *mctx, const cfg_obj_t *config) {
757 const cfg_obj_t *lwreslist = NULL;
758 const cfg_obj_t *lwres = NULL;
759 const cfg_obj_t *listenerslist = NULL;
760 const cfg_listelt_t *element = NULL;
761 ns_lwreslistener_t *listener;
762 ns_lwreslistenerlist_t newlisteners;
763 isc_result_t result;
764 char socktext[ISC_SOCKADDR_FORMATSIZE];
765 isc_sockaddr_t *addrs = NULL;
766 ns_lwresd_t *lwresd = NULL;
767 isc_uint32_t count = 0;
768
769 REQUIRE(mctx != NULL);
770 REQUIRE(config != NULL);
771
772 RUNTIME_CHECK(isc_once_do(&once, initialize_mutex) == ISC_R_SUCCESS);
773
774 ISC_LIST_INIT(newlisteners);
775
776 result = cfg_map_get(config, "lwres", &lwreslist);
777 if (result != ISC_R_SUCCESS)
778 return (ISC_R_SUCCESS);
779
780 LOCK(&listeners_lock);
781 /*
782 * Run through the new lwres address list, noting sockets that
783 * are already being listened on and moving them to the new list.
784 *
785 * Identifying duplicates addr/port combinations is left to either
786 * the underlying config code, or to the bind attempt getting an
787 * address-in-use error.
788 */
789 for (element = cfg_list_first(lwreslist);
790 element != NULL;
791 element = cfg_list_next(element))
792 {
793 in_port_t port;
794
795 lwres = cfg_listelt_value(element);
796 CHECK(ns_lwdmanager_create(mctx, lwres, &lwresd));
797
798 port = lwresd_g_listenport;
799 if (port == 0)
800 port = LWRES_UDP_PORT;
801
802 listenerslist = NULL;
803 (void)cfg_map_get(lwres, "listen-on", &listenerslist);
804 if (listenerslist == NULL) {
805 struct in_addr localhost;
806 isc_sockaddr_t address;
807
808 localhost.s_addr = htonl(INADDR_LOOPBACK);
809 isc_sockaddr_fromin(&address, &localhost, port);
810 CHECK(configure_listener(&address, lwresd, mctx,
811 &newlisteners));
812 } else {
813 isc_uint32_t i;
814
815 CHECK(ns_config_getiplist(config, listenerslist,
816 port, mctx, &addrs, &count));
817 for (i = 0; i < count; i++)
818 CHECK(configure_listener(&addrs[i], lwresd,
819 mctx, &newlisteners));
820 ns_config_putiplist(mctx, &addrs, count);
821 }
822 ns_lwdmanager_detach(&lwresd);
823 }
824
825 /*
826 * Shutdown everything on the listeners list, and remove them from
827 * the list. Then put all of the new listeners on it.
828 */
829
830 while (!ISC_LIST_EMPTY(listeners)) {
831 listener = ISC_LIST_HEAD(listeners);
832 ISC_LIST_UNLINK(listeners, listener, link);
833
834 isc_sockaddr_format(&listener->address,
835 socktext, sizeof(socktext));
836
837 listener_shutdown(listener);
838 ns_lwreslistener_detach(&listener);
839
840 isc_log_write(ns_g_lctx, ISC_LOGCATEGORY_GENERAL,
841 NS_LOGMODULE_LWRESD, ISC_LOG_NOTICE,
842 "lwres no longer listening on %s", socktext);
843 }
844
845 cleanup:
846 ISC_LIST_APPENDLIST(listeners, newlisteners, link);
847
848 if (addrs != NULL)
849 ns_config_putiplist(mctx, &addrs, count);
850
851 if (lwresd != NULL)
852 ns_lwdmanager_detach(&lwresd);
853
854 UNLOCK(&listeners_lock);
855
856 return (result);
857 }
858
859 void
ns_lwresd_shutdown(void)860 ns_lwresd_shutdown(void) {
861 ns_lwreslistener_t *listener;
862
863 RUNTIME_CHECK(isc_once_do(&once, initialize_mutex) == ISC_R_SUCCESS);
864
865 while (!ISC_LIST_EMPTY(listeners)) {
866 listener = ISC_LIST_HEAD(listeners);
867 ISC_LIST_UNLINK(listeners, listener, link);
868 ns_lwreslistener_detach(&listener);
869 }
870 }
871