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Import bind-9.3.4
[dragonfly.git] / contrib / bind-9.3 / lib / dns / adb.c
blob3fe436a2bbb4f4ceee88b4ba546f6f905958217f
1 /*
2 * Copyright (C) 2004-2006 Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 1999-2003 Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and 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: adb.c,v 1.181.2.11.2.26 2006/01/04 23:50:20 marka Exp $ */
19
20 /*
21 * Implementation notes
22 * --------------------
23 *
24 * In finds, if task == NULL, no events will be generated, and no events
25 * have been sent. If task != NULL but taskaction == NULL, an event has been
26 * posted but not yet freed. If neither are NULL, no event was posted.
27 *
28 */
29
30 /*
31 * After we have cleaned all buckets, dump the database contents.
32 */
33 #if 0
34 #define DUMP_ADB_AFTER_CLEANING
35 #endif
36
37 #include <config.h>
38
39 #include <limits.h>
40
41 #include <isc/mutexblock.h>
42 #include <isc/netaddr.h>
43 #include <isc/random.h>
44 #include <isc/string.h> /* Required for HP/UX (and others?) */
45 #include <isc/task.h>
46 #include <isc/timer.h>
47 #include <isc/util.h>
48
49 #include <dns/adb.h>
50 #include <dns/db.h>
51 #include <dns/events.h>
52 #include <dns/log.h>
53 #include <dns/rdata.h>
54 #include <dns/rdataset.h>
55 #include <dns/rdatastruct.h>
56 #include <dns/resolver.h>
57 #include <dns/result.h>
58
59 #define DNS_ADB_MAGIC ISC_MAGIC('D', 'a', 'd', 'b')
60 #define DNS_ADB_VALID(x) ISC_MAGIC_VALID(x, DNS_ADB_MAGIC)
61 #define DNS_ADBNAME_MAGIC ISC_MAGIC('a', 'd', 'b', 'N')
62 #define DNS_ADBNAME_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAME_MAGIC)
63 #define DNS_ADBNAMEHOOK_MAGIC ISC_MAGIC('a', 'd', 'N', 'H')
64 #define DNS_ADBNAMEHOOK_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAMEHOOK_MAGIC)
65 #define DNS_ADBZONEINFO_MAGIC ISC_MAGIC('a', 'd', 'b', 'Z')
66 #define DNS_ADBZONEINFO_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBZONEINFO_MAGIC)
67 #define DNS_ADBENTRY_MAGIC ISC_MAGIC('a', 'd', 'b', 'E')
68 #define DNS_ADBENTRY_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBENTRY_MAGIC)
69 #define DNS_ADBFETCH_MAGIC ISC_MAGIC('a', 'd', 'F', '4')
70 #define DNS_ADBFETCH_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH_MAGIC)
71 #define DNS_ADBFETCH6_MAGIC ISC_MAGIC('a', 'd', 'F', '6')
72 #define DNS_ADBFETCH6_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH6_MAGIC)
73
74 /*
75 * The number of buckets needs to be a prime (for good hashing).
76 *
77 * XXXRTH How many buckets do we need?
78 */
79 #define NBUCKETS 1009 /* how many buckets for names/addrs */
80
81 /*
82 * For type 3 negative cache entries, we will remember that the address is
83 * broken for this long. XXXMLG This is also used for actual addresses, too.
84 * The intent is to keep us from constantly asking about A/AAAA records
85 * if the zone has extremely low TTLs.
86 */
87 #define ADB_CACHE_MINIMUM 10 /* seconds */
88 #define ADB_CACHE_MAXIMUM 86400 /* seconds (86400 = 24 hours) */
89 #define ADB_ENTRY_WINDOW 1800 /* seconds */
90
91 /*
92 * Wake up every CLEAN_SECONDS and clean CLEAN_BUCKETS buckets, so that all
93 * buckets are cleaned in CLEAN_PERIOD seconds.
94 */
95 #define CLEAN_PERIOD 3600
96 #define CLEAN_SECONDS 30
97 #define CLEAN_BUCKETS ((NBUCKETS * CLEAN_SECONDS) / CLEAN_PERIOD)
98
99 #define FREE_ITEMS 64 /* free count for memory pools */
100 #define FILL_COUNT 16 /* fill count for memory pools */
101
102 #define DNS_ADB_INVALIDBUCKET (-1) /* invalid bucket address */
103
104 #define DNS_ADB_MINADBSIZE (1024*1024) /* 1 Megabyte */
105
106 typedef ISC_LIST(dns_adbname_t) dns_adbnamelist_t;
107 typedef struct dns_adbnamehook dns_adbnamehook_t;
108 typedef ISC_LIST(dns_adbnamehook_t) dns_adbnamehooklist_t;
109 typedef struct dns_adbzoneinfo dns_adbzoneinfo_t;
110 typedef ISC_LIST(dns_adbentry_t) dns_adbentrylist_t;
111 typedef struct dns_adbfetch dns_adbfetch_t;
112 typedef struct dns_adbfetch6 dns_adbfetch6_t;
113
114 struct dns_adb {
115 unsigned int magic;
116
117 isc_mutex_t lock;
118 isc_mutex_t reflock; /* Covers irefcnt, erefcnt */
119 isc_mem_t *mctx;
120 dns_view_t *view;
121 isc_timermgr_t *timermgr;
122 isc_timer_t *timer;
123 isc_taskmgr_t *taskmgr;
124 isc_task_t *task;
125 isc_boolean_t overmem;
126
127 isc_interval_t tick_interval;
128 int next_cleanbucket;
129
130 unsigned int irefcnt;
131 unsigned int erefcnt;
132
133 isc_mutex_t mplock;
134 isc_mempool_t *nmp; /* dns_adbname_t */
135 isc_mempool_t *nhmp; /* dns_adbnamehook_t */
136 isc_mempool_t *zimp; /* dns_adbzoneinfo_t */
137 isc_mempool_t *emp; /* dns_adbentry_t */
138 isc_mempool_t *ahmp; /* dns_adbfind_t */
139 isc_mempool_t *aimp; /* dns_adbaddrinfo_t */
140 isc_mempool_t *afmp; /* dns_adbfetch_t */
141
142 /*
143 * Bucketized locks and lists for names.
144 *
145 * XXXRTH Have a per-bucket structure that contains all of these?
146 */
147 dns_adbnamelist_t names[NBUCKETS];
148 isc_mutex_t namelocks[NBUCKETS];
149 isc_boolean_t name_sd[NBUCKETS];
150 unsigned int name_refcnt[NBUCKETS];
151
152 /*
153 * Bucketized locks for entries.
154 *
155 * XXXRTH Have a per-bucket structure that contains all of these?
156 */
157 dns_adbentrylist_t entries[NBUCKETS];
158 isc_mutex_t entrylocks[NBUCKETS];
159 isc_boolean_t entry_sd[NBUCKETS]; /* shutting down */
160 unsigned int entry_refcnt[NBUCKETS];
161
162 isc_event_t cevent;
163 isc_boolean_t cevent_sent;
164 isc_boolean_t shutting_down;
165 isc_eventlist_t whenshutdown;
166 };
167
168 /*
169 * XXXMLG Document these structures.
170 */
171
172 struct dns_adbname {
173 unsigned int magic;
174 dns_name_t name;
175 dns_adb_t *adb;
176 unsigned int partial_result;
177 unsigned int flags;
178 int lock_bucket;
179 dns_name_t target;
180 isc_stdtime_t expire_target;
181 isc_stdtime_t expire_v4;
182 isc_stdtime_t expire_v6;
183 unsigned int chains;
184 dns_adbnamehooklist_t v4;
185 dns_adbnamehooklist_t v6;
186 dns_adbfetch_t *fetch_a;
187 dns_adbfetch_t *fetch_aaaa;
188 unsigned int fetch_err;
189 unsigned int fetch6_err;
190 dns_adbfindlist_t finds;
191 ISC_LINK(dns_adbname_t) plink;
192 };
193
194 struct dns_adbfetch {
195 unsigned int magic;
196 dns_adbnamehook_t *namehook;
197 dns_adbentry_t *entry;
198 dns_fetch_t *fetch;
199 dns_rdataset_t rdataset;
200 };
201
202 /*
203 * dns_adbnamehook_t
204 *
205 * This is a small widget that dangles off a dns_adbname_t. It contains a
206 * pointer to the address information about this host, and a link to the next
207 * namehook that will contain the next address this host has.
208 */
209 struct dns_adbnamehook {
210 unsigned int magic;
211 dns_adbentry_t *entry;
212 ISC_LINK(dns_adbnamehook_t) plink;
213 };
214
215 /*
216 * dns_adbzoneinfo_t
217 *
218 * This is a small widget that holds zone-specific information about an
219 * address. Currently limited to lameness, but could just as easily be
220 * extended to other types of information about zones.
221 */
222 struct dns_adbzoneinfo {
223 unsigned int magic;
224
225 dns_name_t zone;
226 isc_stdtime_t lame_timer;
227
228 ISC_LINK(dns_adbzoneinfo_t) plink;
229 };
230
231 /*
232 * An address entry. It holds quite a bit of information about addresses,
233 * including edns state (in "flags"), rtt, and of course the address of
234 * the host.
235 */
236 struct dns_adbentry {
237 unsigned int magic;
238
239 int lock_bucket;
240 unsigned int refcnt;
241
242 unsigned int flags;
243 unsigned int srtt;
244 isc_sockaddr_t sockaddr;
245
246 isc_stdtime_t expires;
247 /*
248 * A nonzero 'expires' field indicates that the entry should
249 * persist until that time. This allows entries found
250 * using dns_adb_findaddrinfo() to persist for a limited time
251 * even though they are not necessarily associated with a
252 * name.
253 */
254
255 ISC_LIST(dns_adbzoneinfo_t) zoneinfo;
256 ISC_LINK(dns_adbentry_t) plink;
257 };
258
259 /*
260 * Internal functions (and prototypes).
261 */
262 static inline dns_adbname_t *new_adbname(dns_adb_t *, dns_name_t *);
263 static inline void free_adbname(dns_adb_t *, dns_adbname_t **);
264 static inline dns_adbnamehook_t *new_adbnamehook(dns_adb_t *,
265 dns_adbentry_t *);
266 static inline void free_adbnamehook(dns_adb_t *, dns_adbnamehook_t **);
267 static inline dns_adbzoneinfo_t *new_adbzoneinfo(dns_adb_t *, dns_name_t *);
268 static inline void free_adbzoneinfo(dns_adb_t *, dns_adbzoneinfo_t **);
269 static inline dns_adbentry_t *new_adbentry(dns_adb_t *);
270 static inline void free_adbentry(dns_adb_t *, dns_adbentry_t **);
271 static inline dns_adbfind_t *new_adbfind(dns_adb_t *);
272 static inline isc_boolean_t free_adbfind(dns_adb_t *, dns_adbfind_t **);
273 static inline dns_adbaddrinfo_t *new_adbaddrinfo(dns_adb_t *, dns_adbentry_t *,
274 in_port_t);
275 static inline dns_adbfetch_t *new_adbfetch(dns_adb_t *);
276 static inline void free_adbfetch(dns_adb_t *, dns_adbfetch_t **);
277 static inline dns_adbname_t *find_name_and_lock(dns_adb_t *, dns_name_t *,
278 unsigned int, int *);
279 static inline dns_adbentry_t *find_entry_and_lock(dns_adb_t *,
280 isc_sockaddr_t *, int *);
281 static void dump_adb(dns_adb_t *, FILE *, isc_boolean_t debug, isc_stdtime_t);
282 static void print_dns_name(FILE *, dns_name_t *);
283 static void print_namehook_list(FILE *, const char *legend,
284 dns_adbnamehooklist_t *list,
285 isc_boolean_t debug,
286 isc_stdtime_t now);
287 static void print_find_list(FILE *, dns_adbname_t *);
288 static void print_fetch_list(FILE *, dns_adbname_t *);
289 static inline isc_boolean_t dec_adb_irefcnt(dns_adb_t *);
290 static inline void inc_adb_irefcnt(dns_adb_t *);
291 static inline void inc_adb_erefcnt(dns_adb_t *);
292 static inline void inc_entry_refcnt(dns_adb_t *, dns_adbentry_t *,
293 isc_boolean_t);
294 static inline isc_boolean_t dec_entry_refcnt(dns_adb_t *, dns_adbentry_t *,
295 isc_boolean_t);
296 static inline void violate_locking_hierarchy(isc_mutex_t *, isc_mutex_t *);
297 static isc_boolean_t clean_namehooks(dns_adb_t *, dns_adbnamehooklist_t *);
298 static void clean_target(dns_adb_t *, dns_name_t *);
299 static void clean_finds_at_name(dns_adbname_t *, isc_eventtype_t,
300 unsigned int);
301 static isc_boolean_t check_expire_namehooks(dns_adbname_t *, isc_stdtime_t,
302 isc_boolean_t);
303 static void cancel_fetches_at_name(dns_adbname_t *);
304 static isc_result_t dbfind_name(dns_adbname_t *, isc_stdtime_t,
305 dns_rdatatype_t);
306 static isc_result_t fetch_name(dns_adbname_t *, isc_boolean_t,
307 dns_rdatatype_t);
308 static inline void check_exit(dns_adb_t *);
309 static void timer_cleanup(isc_task_t *, isc_event_t *);
310 static void destroy(dns_adb_t *);
311 static isc_boolean_t shutdown_names(dns_adb_t *);
312 static isc_boolean_t shutdown_entries(dns_adb_t *);
313 static inline void link_name(dns_adb_t *, int, dns_adbname_t *);
314 static inline isc_boolean_t unlink_name(dns_adb_t *, dns_adbname_t *);
315 static inline void link_entry(dns_adb_t *, int, dns_adbentry_t *);
316 static inline isc_boolean_t unlink_entry(dns_adb_t *, dns_adbentry_t *);
317 static isc_boolean_t kill_name(dns_adbname_t **, isc_eventtype_t);
318 static void water(void *, int);
319 static void dump_entry(FILE *, dns_adbentry_t *, isc_boolean_t, isc_stdtime_t);
320
321 /*
322 * MUST NOT overlap DNS_ADBFIND_* flags!
323 */
324 #define FIND_EVENT_SENT 0x40000000
325 #define FIND_EVENT_FREED 0x80000000
326 #define FIND_EVENTSENT(h) (((h)->flags & FIND_EVENT_SENT) != 0)
327 #define FIND_EVENTFREED(h) (((h)->flags & FIND_EVENT_FREED) != 0)
328
329 #define NAME_NEEDS_POKE 0x80000000
330 #define NAME_IS_DEAD 0x40000000
331 #define NAME_HINT_OK DNS_ADBFIND_HINTOK
332 #define NAME_GLUE_OK DNS_ADBFIND_GLUEOK
333 #define NAME_STARTATZONE DNS_ADBFIND_STARTATZONE
334 #define NAME_DEAD(n) (((n)->flags & NAME_IS_DEAD) != 0)
335 #define NAME_NEEDSPOKE(n) (((n)->flags & NAME_NEEDS_POKE) != 0)
336 #define NAME_GLUEOK(n) (((n)->flags & NAME_GLUE_OK) != 0)
337 #define NAME_HINTOK(n) (((n)->flags & NAME_HINT_OK) != 0)
338
339 /*
340 * To the name, address classes are all that really exist. If it has a
341 * V6 address it doesn't care if it came from a AAAA query.
342 */
343 #define NAME_HAS_V4(n) (!ISC_LIST_EMPTY((n)->v4))
344 #define NAME_HAS_V6(n) (!ISC_LIST_EMPTY((n)->v6))
345 #define NAME_HAS_ADDRS(n) (NAME_HAS_V4(n) || NAME_HAS_V6(n))
346
347 /*
348 * Fetches are broken out into A and AAAA types. In some cases,
349 * however, it makes more sense to test for a particular class of fetches,
350 * like V4 or V6 above.
351 * Note: since we have removed the support of A6 in adb, FETCH_A and FETCH_AAAA
352 * are now equal to FETCH_V4 and FETCH_V6, respectively.
353 */
354 #define NAME_FETCH_A(n) ((n)->fetch_a != NULL)
355 #define NAME_FETCH_AAAA(n) ((n)->fetch_aaaa != NULL)
356 #define NAME_FETCH_V4(n) (NAME_FETCH_A(n))
357 #define NAME_FETCH_V6(n) (NAME_FETCH_AAAA(n))
358 #define NAME_FETCH(n) (NAME_FETCH_V4(n) || NAME_FETCH_V6(n))
359
360 /*
361 * Find options and tests to see if there are addresses on the list.
362 */
363 #define FIND_WANTEVENT(fn) (((fn)->options & DNS_ADBFIND_WANTEVENT) != 0)
364 #define FIND_WANTEMPTYEVENT(fn) (((fn)->options & DNS_ADBFIND_EMPTYEVENT) != 0)
365 #define FIND_AVOIDFETCHES(fn) (((fn)->options & DNS_ADBFIND_AVOIDFETCHES) \
366 != 0)
367 #define FIND_STARTATZONE(fn) (((fn)->options & DNS_ADBFIND_STARTATZONE) \
368 != 0)
369 #define FIND_HINTOK(fn) (((fn)->options & DNS_ADBFIND_HINTOK) != 0)
370 #define FIND_GLUEOK(fn) (((fn)->options & DNS_ADBFIND_GLUEOK) != 0)
371 #define FIND_HAS_ADDRS(fn) (!ISC_LIST_EMPTY((fn)->list))
372 #define FIND_RETURNLAME(fn) (((fn)->options & DNS_ADBFIND_RETURNLAME) != 0)
373
374 /*
375 * These are currently used on simple unsigned ints, so they are
376 * not really associated with any particular type.
377 */
378 #define WANT_INET(x) (((x) & DNS_ADBFIND_INET) != 0)
379 #define WANT_INET6(x) (((x) & DNS_ADBFIND_INET6) != 0)
380
381 #define EXPIRE_OK(exp, now) ((exp == INT_MAX) || (exp < now))
382
383 /*
384 * Find out if the flags on a name (nf) indicate if it is a hint or
385 * glue, and compare this to the appropriate bits set in o, to see if
386 * this is ok.
387 */
388 #define GLUE_OK(nf, o) (!NAME_GLUEOK(nf) || (((o) & DNS_ADBFIND_GLUEOK) != 0))
389 #define HINT_OK(nf, o) (!NAME_HINTOK(nf) || (((o) & DNS_ADBFIND_HINTOK) != 0))
390 #define GLUEHINT_OK(nf, o) (GLUE_OK(nf, o) || HINT_OK(nf, o))
391 #define STARTATZONE_MATCHES(nf, o) (((nf)->flags & NAME_STARTATZONE) == \
392 ((o) & DNS_ADBFIND_STARTATZONE))
393
394 #define ENTER_LEVEL ISC_LOG_DEBUG(50)
395 #define EXIT_LEVEL ENTER_LEVEL
396 #define CLEAN_LEVEL ISC_LOG_DEBUG(100)
397 #define DEF_LEVEL ISC_LOG_DEBUG(5)
398 #define NCACHE_LEVEL ISC_LOG_DEBUG(20)
399
400 #define NCACHE_RESULT(r) ((r) == DNS_R_NCACHENXDOMAIN || \
401 (r) == DNS_R_NCACHENXRRSET)
402 #define AUTH_NX(r) ((r) == DNS_R_NXDOMAIN || \
403 (r) == DNS_R_NXRRSET)
404 #define NXDOMAIN_RESULT(r) ((r) == DNS_R_NXDOMAIN || \
405 (r) == DNS_R_NCACHENXDOMAIN)
406 #define NXRRSET_RESULT(r) ((r) == DNS_R_NCACHENXRRSET || \
407 (r) == DNS_R_NXRRSET || \
408 (r) == DNS_R_HINTNXRRSET)
409
410 /*
411 * Error state rankings.
412 */
413
414 #define FIND_ERR_SUCCESS 0 /* highest rank */
415 #define FIND_ERR_CANCELED 1
416 #define FIND_ERR_FAILURE 2
417 #define FIND_ERR_NXDOMAIN 3
418 #define FIND_ERR_NXRRSET 4
419 #define FIND_ERR_UNEXPECTED 5
420 #define FIND_ERR_NOTFOUND 6
421 #define FIND_ERR_MAX 7
422
423 static const char *errnames[] = {
424 "success",
425 "canceled",
426 "failure",
427 "nxdomain",
428 "nxrrset",
429 "unexpected",
430 "not_found"
431 };
432
433 #define NEWERR(old, new) (ISC_MIN((old), (new)))
434
435 static isc_result_t find_err_map[FIND_ERR_MAX] = {
436 ISC_R_SUCCESS,
437 ISC_R_CANCELED,
438 ISC_R_FAILURE,
439 DNS_R_NXDOMAIN,
440 DNS_R_NXRRSET,
441 ISC_R_UNEXPECTED,
442 ISC_R_NOTFOUND /* not YET found */
443 };
444
445 static void
446 DP(int level, const char *format, ...) ISC_FORMAT_PRINTF(2, 3);
447
448 static void
449 DP(int level, const char *format, ...) {
450 va_list args;
451
452 va_start(args, format);
453 isc_log_vwrite(dns_lctx,
454 DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_ADB,
455 level, format, args);
456 va_end(args);
457 }
458
459 static inline dns_ttl_t
460 ttlclamp(dns_ttl_t ttl) {
461 if (ttl < ADB_CACHE_MINIMUM)
462 ttl = ADB_CACHE_MINIMUM;
463 if (ttl > ADB_CACHE_MAXIMUM)
464 ttl = ADB_CACHE_MAXIMUM;
465
466 return (ttl);
467 }
468
469 /*
470 * Requires the adbname bucket be locked and that no entry buckets be locked.
471 *
472 * This code handles A and AAAA rdatasets only.
473 */
474 static isc_result_t
475 import_rdataset(dns_adbname_t *adbname, dns_rdataset_t *rdataset,
476 isc_stdtime_t now)
477 {
478 isc_result_t result;
479 dns_adb_t *adb;
480 dns_adbnamehook_t *nh;
481 dns_adbnamehook_t *anh;
482 dns_rdata_t rdata = DNS_RDATA_INIT;
483 struct in_addr ina;
484 struct in6_addr in6a;
485 isc_sockaddr_t sockaddr;
486 dns_adbentry_t *foundentry; /* NO CLEAN UP! */
487 int addr_bucket;
488 isc_boolean_t new_addresses_added;
489 dns_rdatatype_t rdtype;
490 unsigned int findoptions;
491
492 INSIST(DNS_ADBNAME_VALID(adbname));
493 adb = adbname->adb;
494 INSIST(DNS_ADB_VALID(adb));
495
496 rdtype = rdataset->type;
497 INSIST((rdtype == dns_rdatatype_a) || (rdtype == dns_rdatatype_aaaa));
498 if (rdtype == dns_rdatatype_a)
499 findoptions = DNS_ADBFIND_INET;
500 else
501 findoptions = DNS_ADBFIND_INET6;
502
503 addr_bucket = DNS_ADB_INVALIDBUCKET;
504 new_addresses_added = ISC_FALSE;
505
506 nh = NULL;
507 result = dns_rdataset_first(rdataset);
508 while (result == ISC_R_SUCCESS) {
509 dns_rdata_reset(&rdata);
510 dns_rdataset_current(rdataset, &rdata);
511 if (rdtype == dns_rdatatype_a) {
512 INSIST(rdata.length == 4);
513 memcpy(&ina.s_addr, rdata.data, 4);
514 isc_sockaddr_fromin(&sockaddr, &ina, 0);
515 } else {
516 INSIST(rdata.length == 16);
517 memcpy(in6a.s6_addr, rdata.data, 16);
518 isc_sockaddr_fromin6(&sockaddr, &in6a, 0);
519 }
520
521 INSIST(nh == NULL);
522 nh = new_adbnamehook(adb, NULL);
523 if (nh == NULL) {
524 adbname->partial_result |= findoptions;
525 result = ISC_R_NOMEMORY;
526 goto fail;
527 }
528
529 foundentry = find_entry_and_lock(adb, &sockaddr, &addr_bucket);
530 if (foundentry == NULL) {
531 dns_adbentry_t *entry;
532
533 entry = new_adbentry(adb);
534 if (entry == NULL) {
535 adbname->partial_result |= findoptions;
536 result = ISC_R_NOMEMORY;
537 goto fail;
538 }
539
540 entry->sockaddr = sockaddr;
541 entry->refcnt = 1;
542
543 nh->entry = entry;
544
545 link_entry(adb, addr_bucket, entry);
546 } else {
547 for (anh = ISC_LIST_HEAD(adbname->v4);
548 anh != NULL;
549 anh = ISC_LIST_NEXT(anh, plink))
550 if (anh->entry == foundentry)
551 break;
552 if (anh == NULL) {
553 foundentry->refcnt++;
554 nh->entry = foundentry;
555 } else
556 free_adbnamehook(adb, &nh);
557 }
558
559 new_addresses_added = ISC_TRUE;
560 if (nh != NULL) {
561 if (rdtype == dns_rdatatype_a)
562 ISC_LIST_APPEND(adbname->v4, nh, plink);
563 else
564 ISC_LIST_APPEND(adbname->v6, nh, plink);
565 }
566 nh = NULL;
567 result = dns_rdataset_next(rdataset);
568 }
569
570 fail:
571 if (nh != NULL)
572 free_adbnamehook(adb, &nh);
573
574 if (addr_bucket != DNS_ADB_INVALIDBUCKET)
575 UNLOCK(&adb->entrylocks[addr_bucket]);
576
577 if (rdataset->trust == dns_trust_glue ||
578 rdataset->trust == dns_trust_additional)
579 rdataset->ttl = ADB_CACHE_MINIMUM;
580 else
581 rdataset->ttl = ttlclamp(rdataset->ttl);
582
583 if (rdtype == dns_rdatatype_a) {
584 DP(NCACHE_LEVEL, "expire_v4 set to MIN(%u,%u) import_rdataset",
585 adbname->expire_v4, now + rdataset->ttl);
586 adbname->expire_v4 = ISC_MIN(adbname->expire_v4,
587 now + rdataset->ttl);
588 } else {
589 DP(NCACHE_LEVEL, "expire_v6 set to MIN(%u,%u) import_rdataset",
590 adbname->expire_v6, now + rdataset->ttl);
591 adbname->expire_v6 = ISC_MIN(adbname->expire_v6,
592 now + rdataset->ttl);
593 }
594
595 if (new_addresses_added) {
596 /*
597 * Lie a little here. This is more or less so code that cares
598 * can find out if any new information was added or not.
599 */
600 return (ISC_R_SUCCESS);
601 }
602
603 return (result);
604 }
605
606 /*
607 * Requires the name's bucket be locked.
608 */
609 static isc_boolean_t
610 kill_name(dns_adbname_t **n, isc_eventtype_t ev) {
611 dns_adbname_t *name;
612 isc_boolean_t result = ISC_FALSE;
613 isc_boolean_t result4, result6;
614 dns_adb_t *adb;
615
616 INSIST(n != NULL);
617 name = *n;
618 *n = NULL;
619 INSIST(DNS_ADBNAME_VALID(name));
620 adb = name->adb;
621 INSIST(DNS_ADB_VALID(adb));
622
623 DP(DEF_LEVEL, "killing name %p", name);
624
625 /*
626 * If we're dead already, just check to see if we should go
627 * away now or not.
628 */
629 if (NAME_DEAD(name) && !NAME_FETCH(name)) {
630 result = unlink_name(adb, name);
631 free_adbname(adb, &name);
632 if (result)
633 result = dec_adb_irefcnt(adb);
634 return (result);
635 }
636
637 /*
638 * Clean up the name's various lists. These two are destructive
639 * in that they will always empty the list.
640 */
641 clean_finds_at_name(name, ev, DNS_ADBFIND_ADDRESSMASK);
642 result4 = clean_namehooks(adb, &name->v4);
643 result6 = clean_namehooks(adb, &name->v6);
644 clean_target(adb, &name->target);
645 result = ISC_TF(result4 || result6);
646
647 /*
648 * If fetches are running, cancel them. If none are running, we can
649 * just kill the name here.
650 */
651 if (!NAME_FETCH(name)) {
652 INSIST(result == ISC_FALSE);
653 result = unlink_name(adb, name);
654 free_adbname(adb, &name);
655 if (result)
656 result = dec_adb_irefcnt(adb);
657 } else {
658 name->flags |= NAME_IS_DEAD;
659 cancel_fetches_at_name(name);
660 }
661 return (result);
662 }
663
664 /*
665 * Requires the name's bucket be locked and no entry buckets be locked.
666 */
667 static isc_boolean_t
668 check_expire_namehooks(dns_adbname_t *name, isc_stdtime_t now,
669 isc_boolean_t overmem)
670 {
671 dns_adb_t *adb;
672 isc_boolean_t expire;
673 isc_boolean_t result4 = ISC_FALSE;
674 isc_boolean_t result6 = ISC_FALSE;
675
676 INSIST(DNS_ADBNAME_VALID(name));
677 adb = name->adb;
678 INSIST(DNS_ADB_VALID(adb));
679
680 if (overmem) {
681 isc_uint32_t val;
682
683 isc_random_get(&val);
684
685 expire = ISC_TF((val % 4) == 0);
686 } else
687 expire = ISC_FALSE;
688
689 /*
690 * Check to see if we need to remove the v4 addresses
691 */
692 if (!NAME_FETCH_V4(name) &&
693 (expire || EXPIRE_OK(name->expire_v4, now))) {
694 if (NAME_HAS_V4(name)) {
695 DP(DEF_LEVEL, "expiring v4 for name %p", name);
696 result4 = clean_namehooks(adb, &name->v4);
697 name->partial_result &= ~DNS_ADBFIND_INET;
698 }
699 name->expire_v4 = INT_MAX;
700 name->fetch_err = FIND_ERR_UNEXPECTED;
701 }
702
703 /*
704 * Check to see if we need to remove the v6 addresses
705 */
706 if (!NAME_FETCH_V6(name) &&
707 (expire || EXPIRE_OK(name->expire_v6, now))) {
708 if (NAME_HAS_V6(name)) {
709 DP(DEF_LEVEL, "expiring v6 for name %p", name);
710 result6 = clean_namehooks(adb, &name->v6);
711 name->partial_result &= ~DNS_ADBFIND_INET6;
712 }
713 name->expire_v6 = INT_MAX;
714 name->fetch6_err = FIND_ERR_UNEXPECTED;
715 }
716
717 /*
718 * Check to see if we need to remove the alias target.
719 */
720 if (expire || EXPIRE_OK(name->expire_target, now)) {
721 clean_target(adb, &name->target);
722 name->expire_target = INT_MAX;
723 }
724 return (ISC_TF(result4 || result6));
725 }
726
727 /*
728 * Requires the name's bucket be locked.
729 */
730 static inline void
731 link_name(dns_adb_t *adb, int bucket, dns_adbname_t *name) {
732 INSIST(name->lock_bucket == DNS_ADB_INVALIDBUCKET);
733
734 ISC_LIST_PREPEND(adb->names[bucket], name, plink);
735 name->lock_bucket = bucket;
736 adb->name_refcnt[bucket]++;
737 }
738
739 /*
740 * Requires the name's bucket be locked.
741 */
742 static inline isc_boolean_t
743 unlink_name(dns_adb_t *adb, dns_adbname_t *name) {
744 int bucket;
745 isc_boolean_t result = ISC_FALSE;
746
747 bucket = name->lock_bucket;
748 INSIST(bucket != DNS_ADB_INVALIDBUCKET);
749
750 ISC_LIST_UNLINK(adb->names[bucket], name, plink);
751 name->lock_bucket = DNS_ADB_INVALIDBUCKET;
752 INSIST(adb->name_refcnt[bucket] > 0);
753 adb->name_refcnt[bucket]--;
754 if (adb->name_sd[bucket] && adb->name_refcnt[bucket] == 0)
755 result = ISC_TRUE;
756 return (result);
757 }
758
759 /*
760 * Requires the entry's bucket be locked.
761 */
762 static inline void
763 link_entry(dns_adb_t *adb, int bucket, dns_adbentry_t *entry) {
764 ISC_LIST_PREPEND(adb->entries[bucket], entry, plink);
765 entry->lock_bucket = bucket;
766 adb->entry_refcnt[bucket]++;
767 }
768
769 /*
770 * Requires the entry's bucket be locked.
771 */
772 static inline isc_boolean_t
773 unlink_entry(dns_adb_t *adb, dns_adbentry_t *entry) {
774 int bucket;
775 isc_boolean_t result = ISC_FALSE;
776
777 bucket = entry->lock_bucket;
778 INSIST(bucket != DNS_ADB_INVALIDBUCKET);
779
780 ISC_LIST_UNLINK(adb->entries[bucket], entry, plink);
781 entry->lock_bucket = DNS_ADB_INVALIDBUCKET;
782 INSIST(adb->entry_refcnt[bucket] > 0);
783 adb->entry_refcnt[bucket]--;
784 if (adb->entry_sd[bucket] && adb->entry_refcnt[bucket] == 0)
785 result = ISC_TRUE;
786 return (result);
787 }
788
789 static inline void
790 violate_locking_hierarchy(isc_mutex_t *have, isc_mutex_t *want) {
791 if (isc_mutex_trylock(want) != ISC_R_SUCCESS) {
792 UNLOCK(have);
793 LOCK(want);
794 LOCK(have);
795 }
796 }
797
798 /*
799 * The ADB _MUST_ be locked before calling. Also, exit conditions must be
800 * checked after calling this function.
801 */
802 static isc_boolean_t
803 shutdown_names(dns_adb_t *adb) {
804 int bucket;
805 isc_boolean_t result = ISC_FALSE;
806 dns_adbname_t *name;
807 dns_adbname_t *next_name;
808
809 for (bucket = 0; bucket < NBUCKETS; bucket++) {
810 LOCK(&adb->namelocks[bucket]);
811 adb->name_sd[bucket] = ISC_TRUE;
812
813 name = ISC_LIST_HEAD(adb->names[bucket]);
814 if (name == NULL) {
815 /*
816 * This bucket has no names. We must decrement the
817 * irefcnt ourselves, since it will not be
818 * automatically triggered by a name being unlinked.
819 */
820 INSIST(result == ISC_FALSE);
821 result = dec_adb_irefcnt(adb);
822 } else {
823 /*
824 * Run through the list. For each name, clean up finds
825 * found there, and cancel any fetches running. When
826 * all the fetches are canceled, the name will destroy
827 * itself.
828 */
829 while (name != NULL) {
830 next_name = ISC_LIST_NEXT(name, plink);
831 INSIST(result == ISC_FALSE);
832 result = kill_name(&name,
833 DNS_EVENT_ADBSHUTDOWN);
834 name = next_name;
835 }
836 }
837
838 UNLOCK(&adb->namelocks[bucket]);
839 }
840 return (result);
841 }
842
843 /*
844 * The ADB _MUST_ be locked before calling. Also, exit conditions must be
845 * checked after calling this function.
846 */
847 static isc_boolean_t
848 shutdown_entries(dns_adb_t *adb) {
849 int bucket;
850 isc_boolean_t result = ISC_FALSE;
851 dns_adbentry_t *entry;
852 dns_adbentry_t *next_entry;
853
854 for (bucket = 0; bucket < NBUCKETS; bucket++) {
855 LOCK(&adb->entrylocks[bucket]);
856 adb->entry_sd[bucket] = ISC_TRUE;
857
858 entry = ISC_LIST_HEAD(adb->entries[bucket]);
859 if (entry == NULL) {
860 /*
861 * This bucket has no entries. We must decrement the
862 * irefcnt ourselves, since it will not be
863 * automatically triggered by an entry being unlinked.
864 */
865 result = dec_adb_irefcnt(adb);
866 } else {
867 /*
868 * Run through the list. Cleanup any entries not
869 * associated with names, and which are not in use.
870 */
871 while (entry != NULL) {
872 next_entry = ISC_LIST_NEXT(entry, plink);
873 if (entry->refcnt == 0 &&
874 entry->expires != 0) {
875 result = unlink_entry(adb, entry);
876 free_adbentry(adb, &entry);
877 if (result)
878 result = dec_adb_irefcnt(adb);
879 }
880 entry = next_entry;
881 }
882 }
883
884 UNLOCK(&adb->entrylocks[bucket]);
885 }
886 return (result);
887 }
888
889 /*
890 * Name bucket must be locked
891 */
892 static void
893 cancel_fetches_at_name(dns_adbname_t *name) {
894 if (NAME_FETCH_A(name))
895 dns_resolver_cancelfetch(name->fetch_a->fetch);
896
897 if (NAME_FETCH_AAAA(name))
898 dns_resolver_cancelfetch(name->fetch_aaaa->fetch);
899 }
900
901 /*
902 * Assumes the name bucket is locked.
903 */
904 static isc_boolean_t
905 clean_namehooks(dns_adb_t *adb, dns_adbnamehooklist_t *namehooks) {
906 dns_adbentry_t *entry;
907 dns_adbnamehook_t *namehook;
908 int addr_bucket;
909 isc_boolean_t result = ISC_FALSE;
910
911 addr_bucket = DNS_ADB_INVALIDBUCKET;
912 namehook = ISC_LIST_HEAD(*namehooks);
913 while (namehook != NULL) {
914 INSIST(DNS_ADBNAMEHOOK_VALID(namehook));
915
916 /*
917 * Clean up the entry if needed.
918 */
919 entry = namehook->entry;
920 if (entry != NULL) {
921 INSIST(DNS_ADBENTRY_VALID(entry));
922
923 if (addr_bucket != entry->lock_bucket) {
924 if (addr_bucket != DNS_ADB_INVALIDBUCKET)
925 UNLOCK(&adb->entrylocks[addr_bucket]);
926 addr_bucket = entry->lock_bucket;
927 LOCK(&adb->entrylocks[addr_bucket]);
928 }
929
930 result = dec_entry_refcnt(adb, entry, ISC_FALSE);
931 }
932
933 /*
934 * Free the namehook
935 */
936 namehook->entry = NULL;
937 ISC_LIST_UNLINK(*namehooks, namehook, plink);
938 free_adbnamehook(adb, &namehook);
939
940 namehook = ISC_LIST_HEAD(*namehooks);
941 }
942
943 if (addr_bucket != DNS_ADB_INVALIDBUCKET)
944 UNLOCK(&adb->entrylocks[addr_bucket]);
945 return (result);
946 }
947
948 static void
949 clean_target(dns_adb_t *adb, dns_name_t *target) {
950 if (dns_name_countlabels(target) > 0) {
951 dns_name_free(target, adb->mctx);
952 dns_name_init(target, NULL);
953 }
954 }
955
956 static isc_result_t
957 set_target(dns_adb_t *adb, dns_name_t *name, dns_name_t *fname,
958 dns_rdataset_t *rdataset, dns_name_t *target)
959 {
960 isc_result_t result;
961 dns_namereln_t namereln;
962 unsigned int nlabels;
963 int order;
964 dns_rdata_t rdata = DNS_RDATA_INIT;
965 dns_fixedname_t fixed1, fixed2;
966 dns_name_t *prefix, *new_target;
967
968 REQUIRE(dns_name_countlabels(target) == 0);
969
970 if (rdataset->type == dns_rdatatype_cname) {
971 dns_rdata_cname_t cname;
972
973 /*
974 * Copy the CNAME's target into the target name.
975 */
976 result = dns_rdataset_first(rdataset);
977 if (result != ISC_R_SUCCESS)
978 return (result);
979 dns_rdataset_current(rdataset, &rdata);
980 result = dns_rdata_tostruct(&rdata, &cname, NULL);
981 if (result != ISC_R_SUCCESS)
982 return (result);
983 result = dns_name_dup(&cname.cname, adb->mctx, target);
984 dns_rdata_freestruct(&cname);
985 if (result != ISC_R_SUCCESS)
986 return (result);
987 } else {
988 dns_rdata_dname_t dname;
989
990 INSIST(rdataset->type == dns_rdatatype_dname);
991 namereln = dns_name_fullcompare(name, fname, &order, &nlabels);
992 INSIST(namereln == dns_namereln_subdomain);
993 /*
994 * Get the target name of the DNAME.
995 */
996 result = dns_rdataset_first(rdataset);
997 if (result != ISC_R_SUCCESS)
998 return (result);
999 dns_rdataset_current(rdataset, &rdata);
1000 result = dns_rdata_tostruct(&rdata, &dname, NULL);
1001 if (result != ISC_R_SUCCESS)
1002 return (result);
1003 /*
1004 * Construct the new target name.
1005 */
1006 dns_fixedname_init(&fixed1);
1007 prefix = dns_fixedname_name(&fixed1);
1008 dns_fixedname_init(&fixed2);
1009 new_target = dns_fixedname_name(&fixed2);
1010 dns_name_split(name, nlabels, prefix, NULL);
1011 result = dns_name_concatenate(prefix, &dname.dname, new_target,
1012 NULL);
1013 dns_rdata_freestruct(&dname);
1014 if (result != ISC_R_SUCCESS)
1015 return (result);
1016 result = dns_name_dup(new_target, adb->mctx, target);
1017 if (result != ISC_R_SUCCESS)
1018 return (result);
1019 }
1020
1021 return (ISC_R_SUCCESS);
1022 }
1023
1024 /*
1025 * Assumes nothing is locked, since this is called by the client.
1026 */
1027 static void
1028 event_free(isc_event_t *event) {
1029 dns_adbfind_t *find;
1030
1031 INSIST(event != NULL);
1032 find = event->ev_destroy_arg;
1033 INSIST(DNS_ADBFIND_VALID(find));
1034
1035 LOCK(&find->lock);
1036 find->flags |= FIND_EVENT_FREED;
1037 event->ev_destroy_arg = NULL;
1038 UNLOCK(&find->lock);
1039 }
1040
1041 /*
1042 * Assumes the name bucket is locked.
1043 */
1044 static void
1045 clean_finds_at_name(dns_adbname_t *name, isc_eventtype_t evtype,
1046 unsigned int addrs)
1047 {
1048 isc_event_t *ev;
1049 isc_task_t *task;
1050 dns_adbfind_t *find;
1051 dns_adbfind_t *next_find;
1052 isc_boolean_t process;
1053 unsigned int wanted, notify;
1054
1055 DP(ENTER_LEVEL,
1056 "ENTER clean_finds_at_name, name %p, evtype %08x, addrs %08x",
1057 name, evtype, addrs);
1058
1059 find = ISC_LIST_HEAD(name->finds);
1060 while (find != NULL) {
1061 LOCK(&find->lock);
1062 next_find = ISC_LIST_NEXT(find, plink);
1063
1064 process = ISC_FALSE;
1065 wanted = find->flags & DNS_ADBFIND_ADDRESSMASK;
1066 notify = wanted & addrs;
1067
1068 switch (evtype) {
1069 case DNS_EVENT_ADBMOREADDRESSES:
1070 DP(ISC_LOG_DEBUG(3), "DNS_EVENT_ADBMOREADDRESSES");
1071 if ((notify) != 0) {
1072 find->flags &= ~addrs;
1073 process = ISC_TRUE;
1074 }
1075 break;
1076 case DNS_EVENT_ADBNOMOREADDRESSES:
1077 DP(ISC_LOG_DEBUG(3), "DNS_EVENT_ADBNOMOREADDRESSES");
1078 find->flags &= ~addrs;
1079 wanted = find->flags & DNS_ADBFIND_ADDRESSMASK;
1080 if (wanted == 0)
1081 process = ISC_TRUE;
1082 break;
1083 default:
1084 find->flags &= ~addrs;
1085 process = ISC_TRUE;
1086 }
1087
1088 if (process) {
1089 DP(DEF_LEVEL, "cfan: processing find %p", find);
1090 /*
1091 * Unlink the find from the name, letting the caller
1092 * call dns_adb_destroyfind() on it to clean it up
1093 * later.
1094 */
1095 ISC_LIST_UNLINK(name->finds, find, plink);
1096 find->adbname = NULL;
1097 find->name_bucket = DNS_ADB_INVALIDBUCKET;
1098
1099 INSIST(!FIND_EVENTSENT(find));
1100
1101 ev = &find->event;
1102 task = ev->ev_sender;
1103 ev->ev_sender = find;
1104 find->result_v4 = find_err_map[name->fetch_err];
1105 find->result_v6 = find_err_map[name->fetch6_err];
1106 ev->ev_type = evtype;
1107 ev->ev_destroy = event_free;
1108 ev->ev_destroy_arg = find;
1109
1110 DP(DEF_LEVEL,
1111 "sending event %p to task %p for find %p",
1112 ev, task, find);
1113
1114 isc_task_sendanddetach(&task, (isc_event_t **)&ev);
1115 } else {
1116 DP(DEF_LEVEL, "cfan: skipping find %p", find);
1117 }
1118
1119 UNLOCK(&find->lock);
1120 find = next_find;
1121 }
1122
1123 DP(ENTER_LEVEL, "EXIT clean_finds_at_name, name %p", name);
1124 }
1125
1126 static inline void
1127 check_exit(dns_adb_t *adb) {
1128 isc_event_t *event;
1129 /*
1130 * The caller must be holding the adb lock.
1131 */
1132 if (adb->shutting_down) {
1133 /*
1134 * If there aren't any external references either, we're
1135 * done. Send the control event to initiate shutdown.
1136 */
1137 INSIST(!adb->cevent_sent); /* Sanity check. */
1138 event = &adb->cevent;
1139 isc_task_send(adb->task, &event);
1140 adb->cevent_sent = ISC_TRUE;
1141 }
1142 }
1143
1144 static inline isc_boolean_t
1145 dec_adb_irefcnt(dns_adb_t *adb) {
1146 isc_event_t *event;
1147 isc_task_t *etask;
1148 isc_boolean_t result = ISC_FALSE;
1149
1150 LOCK(&adb->reflock);
1151
1152 INSIST(adb->irefcnt > 0);
1153 adb->irefcnt--;
1154
1155 if (adb->irefcnt == 0) {
1156 event = ISC_LIST_HEAD(adb->whenshutdown);
1157 while (event != NULL) {
1158 ISC_LIST_UNLINK(adb->whenshutdown, event, ev_link);
1159 etask = event->ev_sender;
1160 event->ev_sender = adb;
1161 isc_task_sendanddetach(&etask, &event);
1162 event = ISC_LIST_HEAD(adb->whenshutdown);
1163 }
1164 }
1165
1166 if (adb->irefcnt == 0 && adb->erefcnt == 0)
1167 result = ISC_TRUE;
1168 UNLOCK(&adb->reflock);
1169 return (result);
1170 }
1171
1172 static inline void
1173 inc_adb_irefcnt(dns_adb_t *adb) {
1174 LOCK(&adb->reflock);
1175 adb->irefcnt++;
1176 UNLOCK(&adb->reflock);
1177 }
1178
1179 static inline void
1180 inc_adb_erefcnt(dns_adb_t *adb) {
1181 LOCK(&adb->reflock);
1182 adb->erefcnt++;
1183 UNLOCK(&adb->reflock);
1184 }
1185
1186 static inline void
1187 inc_entry_refcnt(dns_adb_t *adb, dns_adbentry_t *entry, isc_boolean_t lock) {
1188 int bucket;
1189
1190 bucket = entry->lock_bucket;
1191
1192 if (lock)
1193 LOCK(&adb->entrylocks[bucket]);
1194
1195 entry->refcnt++;
1196
1197 if (lock)
1198 UNLOCK(&adb->entrylocks[bucket]);
1199 }
1200
1201 static inline isc_boolean_t
1202 dec_entry_refcnt(dns_adb_t *adb, dns_adbentry_t *entry, isc_boolean_t lock) {
1203 int bucket;
1204 isc_boolean_t destroy_entry;
1205 isc_boolean_t result = ISC_FALSE;
1206
1207 bucket = entry->lock_bucket;
1208
1209 if (lock)
1210 LOCK(&adb->entrylocks[bucket]);
1211
1212 INSIST(entry->refcnt > 0);
1213 entry->refcnt--;
1214
1215 destroy_entry = ISC_FALSE;
1216 if (entry->refcnt == 0 &&
1217 (adb->entry_sd[bucket] || entry->expires == 0)) {
1218 destroy_entry = ISC_TRUE;
1219 result = unlink_entry(adb, entry);
1220 }
1221
1222 if (lock)
1223 UNLOCK(&adb->entrylocks[bucket]);
1224
1225 if (!destroy_entry)
1226 return (result);
1227
1228 entry->lock_bucket = DNS_ADB_INVALIDBUCKET;
1229
1230 free_adbentry(adb, &entry);
1231 if (result)
1232 result =dec_adb_irefcnt(adb);
1233
1234 return (result);
1235 }
1236
1237 static inline dns_adbname_t *
1238 new_adbname(dns_adb_t *adb, dns_name_t *dnsname) {
1239 dns_adbname_t *name;
1240
1241 name = isc_mempool_get(adb->nmp);
1242 if (name == NULL)
1243 return (NULL);
1244
1245 dns_name_init(&name->name, NULL);
1246 if (dns_name_dup(dnsname, adb->mctx, &name->name) != ISC_R_SUCCESS) {
1247 isc_mempool_put(adb->nmp, name);
1248 return (NULL);
1249 }
1250 dns_name_init(&name->target, NULL);
1251 name->magic = DNS_ADBNAME_MAGIC;
1252 name->adb = adb;
1253 name->partial_result = 0;
1254 name->flags = 0;
1255 name->expire_v4 = INT_MAX;
1256 name->expire_v6 = INT_MAX;
1257 name->expire_target = INT_MAX;
1258 name->chains = 0;
1259 name->lock_bucket = DNS_ADB_INVALIDBUCKET;
1260 ISC_LIST_INIT(name->v4);
1261 ISC_LIST_INIT(name->v6);
1262 name->fetch_a = NULL;
1263 name->fetch_aaaa = NULL;
1264 name->fetch_err = FIND_ERR_UNEXPECTED;
1265 name->fetch6_err = FIND_ERR_UNEXPECTED;
1266 ISC_LIST_INIT(name->finds);
1267 ISC_LINK_INIT(name, plink);
1268
1269 return (name);
1270 }
1271
1272 static inline void
1273 free_adbname(dns_adb_t *adb, dns_adbname_t **name) {
1274 dns_adbname_t *n;
1275
1276 INSIST(name != NULL && DNS_ADBNAME_VALID(*name));
1277 n = *name;
1278 *name = NULL;
1279
1280 INSIST(!NAME_HAS_V4(n));
1281 INSIST(!NAME_HAS_V6(n));
1282 INSIST(!NAME_FETCH(n));
1283 INSIST(ISC_LIST_EMPTY(n->finds));
1284 INSIST(!ISC_LINK_LINKED(n, plink));
1285 INSIST(n->lock_bucket == DNS_ADB_INVALIDBUCKET);
1286 INSIST(n->adb == adb);
1287
1288 n->magic = 0;
1289 dns_name_free(&n->name, adb->mctx);
1290
1291 isc_mempool_put(adb->nmp, n);
1292 }
1293
1294 static inline dns_adbnamehook_t *
1295 new_adbnamehook(dns_adb_t *adb, dns_adbentry_t *entry) {
1296 dns_adbnamehook_t *nh;
1297
1298 nh = isc_mempool_get(adb->nhmp);
1299 if (nh == NULL)
1300 return (NULL);
1301
1302 nh->magic = DNS_ADBNAMEHOOK_MAGIC;
1303 nh->entry = entry;
1304 ISC_LINK_INIT(nh, plink);
1305
1306 return (nh);
1307 }
1308
1309 static inline void
1310 free_adbnamehook(dns_adb_t *adb, dns_adbnamehook_t **namehook) {
1311 dns_adbnamehook_t *nh;
1312
1313 INSIST(namehook != NULL && DNS_ADBNAMEHOOK_VALID(*namehook));
1314 nh = *namehook;
1315 *namehook = NULL;
1316
1317 INSIST(nh->entry == NULL);
1318 INSIST(!ISC_LINK_LINKED(nh, plink));
1319
1320 nh->magic = 0;
1321 isc_mempool_put(adb->nhmp, nh);
1322 }
1323
1324 static inline dns_adbzoneinfo_t *
1325 new_adbzoneinfo(dns_adb_t *adb, dns_name_t *zone) {
1326 dns_adbzoneinfo_t *zi;
1327
1328 zi = isc_mempool_get(adb->zimp);
1329 if (zi == NULL)
1330 return (NULL);
1331
1332 dns_name_init(&zi->zone, NULL);
1333 if (dns_name_dup(zone, adb->mctx, &zi->zone) != ISC_R_SUCCESS) {
1334 isc_mempool_put(adb->zimp, zi);
1335 return (NULL);
1336 }
1337
1338 zi->magic = DNS_ADBZONEINFO_MAGIC;
1339 zi->lame_timer = 0;
1340 ISC_LINK_INIT(zi, plink);
1341
1342 return (zi);
1343 }
1344
1345 static inline void
1346 free_adbzoneinfo(dns_adb_t *adb, dns_adbzoneinfo_t **zoneinfo) {
1347 dns_adbzoneinfo_t *zi;
1348
1349 INSIST(zoneinfo != NULL && DNS_ADBZONEINFO_VALID(*zoneinfo));
1350 zi = *zoneinfo;
1351 *zoneinfo = NULL;
1352
1353 INSIST(!ISC_LINK_LINKED(zi, plink));
1354
1355 dns_name_free(&zi->zone, adb->mctx);
1356
1357 zi->magic = 0;
1358
1359 isc_mempool_put(adb->zimp, zi);
1360 }
1361
1362 static inline dns_adbentry_t *
1363 new_adbentry(dns_adb_t *adb) {
1364 dns_adbentry_t *e;
1365 isc_uint32_t r;
1366
1367 e = isc_mempool_get(adb->emp);
1368 if (e == NULL)
1369 return (NULL);
1370
1371 e->magic = DNS_ADBENTRY_MAGIC;
1372 e->lock_bucket = DNS_ADB_INVALIDBUCKET;
1373 e->refcnt = 0;
1374 e->flags = 0;
1375 isc_random_get(&r);
1376 e->srtt = (r & 0x1f) + 1;
1377 e->expires = 0;
1378 ISC_LIST_INIT(e->zoneinfo);
1379 ISC_LINK_INIT(e, plink);
1380
1381 return (e);
1382 }
1383
1384 static inline void
1385 free_adbentry(dns_adb_t *adb, dns_adbentry_t **entry) {
1386 dns_adbentry_t *e;
1387 dns_adbzoneinfo_t *zi;
1388
1389 INSIST(entry != NULL && DNS_ADBENTRY_VALID(*entry));
1390 e = *entry;
1391 *entry = NULL;
1392
1393 INSIST(e->lock_bucket == DNS_ADB_INVALIDBUCKET);
1394 INSIST(e->refcnt == 0);
1395 INSIST(!ISC_LINK_LINKED(e, plink));
1396
1397 e->magic = 0;
1398
1399 zi = ISC_LIST_HEAD(e->zoneinfo);
1400 while (zi != NULL) {
1401 ISC_LIST_UNLINK(e->zoneinfo, zi, plink);
1402 free_adbzoneinfo(adb, &zi);
1403 zi = ISC_LIST_HEAD(e->zoneinfo);
1404 }
1405
1406 isc_mempool_put(adb->emp, e);
1407 }
1408
1409 static inline dns_adbfind_t *
1410 new_adbfind(dns_adb_t *adb) {
1411 dns_adbfind_t *h;
1412 isc_result_t result;
1413
1414 h = isc_mempool_get(adb->ahmp);
1415 if (h == NULL)
1416 return (NULL);
1417
1418 /*
1419 * Public members.
1420 */
1421 h->magic = 0;
1422 h->adb = adb;
1423 h->partial_result = 0;
1424 h->options = 0;
1425 h->flags = 0;
1426 h->result_v4 = ISC_R_UNEXPECTED;
1427 h->result_v6 = ISC_R_UNEXPECTED;
1428 ISC_LINK_INIT(h, publink);
1429 ISC_LINK_INIT(h, plink);
1430 ISC_LIST_INIT(h->list);
1431 h->adbname = NULL;
1432 h->name_bucket = DNS_ADB_INVALIDBUCKET;
1433
1434 /*
1435 * private members
1436 */
1437 result = isc_mutex_init(&h->lock);
1438 if (result != ISC_R_SUCCESS) {
1439 UNEXPECTED_ERROR(__FILE__, __LINE__,
1440 "isc_mutex_init failed in new_adbfind()");
1441 isc_mempool_put(adb->ahmp, h);
1442 return (NULL);
1443 }
1444
1445 ISC_EVENT_INIT(&h->event, sizeof(isc_event_t), 0, 0, 0, NULL, NULL,
1446 NULL, NULL, h);
1447
1448 inc_adb_irefcnt(adb);
1449 h->magic = DNS_ADBFIND_MAGIC;
1450 return (h);
1451 }
1452
1453 static inline dns_adbfetch_t *
1454 new_adbfetch(dns_adb_t *adb) {
1455 dns_adbfetch_t *f;
1456
1457 f = isc_mempool_get(adb->afmp);
1458 if (f == NULL)
1459 return (NULL);
1460
1461 f->magic = 0;
1462 f->namehook = NULL;
1463 f->entry = NULL;
1464 f->fetch = NULL;
1465
1466 f->namehook = new_adbnamehook(adb, NULL);
1467 if (f->namehook == NULL)
1468 goto err;
1469
1470 f->entry = new_adbentry(adb);
1471 if (f->entry == NULL)
1472 goto err;
1473
1474 dns_rdataset_init(&f->rdataset);
1475
1476 f->magic = DNS_ADBFETCH_MAGIC;
1477
1478 return (f);
1479
1480 err:
1481 if (f->namehook != NULL)
1482 free_adbnamehook(adb, &f->namehook);
1483 if (f->entry != NULL)
1484 free_adbentry(adb, &f->entry);
1485 isc_mempool_put(adb->afmp, f);
1486 return (NULL);
1487 }
1488
1489 static inline void
1490 free_adbfetch(dns_adb_t *adb, dns_adbfetch_t **fetch) {
1491 dns_adbfetch_t *f;
1492
1493 INSIST(fetch != NULL && DNS_ADBFETCH_VALID(*fetch));
1494 f = *fetch;
1495 *fetch = NULL;
1496
1497 f->magic = 0;
1498
1499 if (f->namehook != NULL)
1500 free_adbnamehook(adb, &f->namehook);
1501 if (f->entry != NULL)
1502 free_adbentry(adb, &f->entry);
1503
1504 if (dns_rdataset_isassociated(&f->rdataset))
1505 dns_rdataset_disassociate(&f->rdataset);
1506
1507 isc_mempool_put(adb->afmp, f);
1508 }
1509
1510 static inline isc_boolean_t
1511 free_adbfind(dns_adb_t *adb, dns_adbfind_t **findp) {
1512 dns_adbfind_t *find;
1513
1514 INSIST(findp != NULL && DNS_ADBFIND_VALID(*findp));
1515 find = *findp;
1516 *findp = NULL;
1517
1518 INSIST(!FIND_HAS_ADDRS(find));
1519 INSIST(!ISC_LINK_LINKED(find, publink));
1520 INSIST(!ISC_LINK_LINKED(find, plink));
1521 INSIST(find->name_bucket == DNS_ADB_INVALIDBUCKET);
1522 INSIST(find->adbname == NULL);
1523
1524 find->magic = 0;
1525
1526 DESTROYLOCK(&find->lock);
1527 isc_mempool_put(adb->ahmp, find);
1528 return (dec_adb_irefcnt(adb));
1529 }
1530
1531 /*
1532 * Copy bits from the entry into the newly allocated addrinfo. The entry
1533 * must be locked, and the reference count must be bumped up by one
1534 * if this function returns a valid pointer.
1535 */
1536 static inline dns_adbaddrinfo_t *
1537 new_adbaddrinfo(dns_adb_t *adb, dns_adbentry_t *entry, in_port_t port) {
1538 dns_adbaddrinfo_t *ai;
1539
1540 ai = isc_mempool_get(adb->aimp);
1541 if (ai == NULL)
1542 return (NULL);
1543
1544 ai->magic = DNS_ADBADDRINFO_MAGIC;
1545 ai->sockaddr = entry->sockaddr;
1546 isc_sockaddr_setport(&ai->sockaddr, port);
1547 ai->srtt = entry->srtt;
1548 ai->flags = entry->flags;
1549 ai->entry = entry;
1550 ISC_LINK_INIT(ai, publink);
1551
1552 return (ai);
1553 }
1554
1555 static inline void
1556 free_adbaddrinfo(dns_adb_t *adb, dns_adbaddrinfo_t **ainfo) {
1557 dns_adbaddrinfo_t *ai;
1558
1559 INSIST(ainfo != NULL && DNS_ADBADDRINFO_VALID(*ainfo));
1560 ai = *ainfo;
1561 *ainfo = NULL;
1562
1563 INSIST(ai->entry == NULL);
1564 INSIST(!ISC_LINK_LINKED(ai, publink));
1565
1566 ai->magic = 0;
1567
1568 isc_mempool_put(adb->aimp, ai);
1569 }
1570
1571 /*
1572 * Search for the name. NOTE: The bucket is kept locked on both
1573 * success and failure, so it must always be unlocked by the caller!
1574 *
1575 * On the first call to this function, *bucketp must be set to
1576 * DNS_ADB_INVALIDBUCKET.
1577 */
1578 static inline dns_adbname_t *
1579 find_name_and_lock(dns_adb_t *adb, dns_name_t *name,
1580 unsigned int options, int *bucketp)
1581 {
1582 dns_adbname_t *adbname;
1583 int bucket;
1584
1585 bucket = dns_name_fullhash(name, ISC_FALSE) % NBUCKETS;
1586
1587 if (*bucketp == DNS_ADB_INVALIDBUCKET) {
1588 LOCK(&adb->namelocks[bucket]);
1589 *bucketp = bucket;
1590 } else if (*bucketp != bucket) {
1591 UNLOCK(&adb->namelocks[*bucketp]);
1592 LOCK(&adb->namelocks[bucket]);
1593 *bucketp = bucket;
1594 }
1595
1596 adbname = ISC_LIST_HEAD(adb->names[bucket]);
1597 while (adbname != NULL) {
1598 if (!NAME_DEAD(adbname)) {
1599 if (dns_name_equal(name, &adbname->name)
1600 && GLUEHINT_OK(adbname, options)
1601 && STARTATZONE_MATCHES(adbname, options))
1602 return (adbname);
1603 }
1604 adbname = ISC_LIST_NEXT(adbname, plink);
1605 }
1606
1607 return (NULL);
1608 }
1609
1610 /*
1611 * Search for the address. NOTE: The bucket is kept locked on both
1612 * success and failure, so it must always be unlocked by the caller.
1613 *
1614 * On the first call to this function, *bucketp must be set to
1615 * DNS_ADB_INVALIDBUCKET. This will cause a lock to occur. On
1616 * later calls (within the same "lock path") it can be left alone, so
1617 * if this function is called multiple times locking is only done if
1618 * the bucket changes.
1619 */
1620 static inline dns_adbentry_t *
1621 find_entry_and_lock(dns_adb_t *adb, isc_sockaddr_t *addr, int *bucketp) {
1622 dns_adbentry_t *entry;
1623 int bucket;
1624
1625 bucket = isc_sockaddr_hash(addr, ISC_TRUE) % NBUCKETS;
1626
1627 if (*bucketp == DNS_ADB_INVALIDBUCKET) {
1628 LOCK(&adb->entrylocks[bucket]);
1629 *bucketp = bucket;
1630 } else if (*bucketp != bucket) {
1631 UNLOCK(&adb->entrylocks[*bucketp]);
1632 LOCK(&adb->entrylocks[bucket]);
1633 *bucketp = bucket;
1634 }
1635
1636 entry = ISC_LIST_HEAD(adb->entries[bucket]);
1637 while (entry != NULL) {
1638 if (isc_sockaddr_equal(addr, &entry->sockaddr))
1639 return (entry);
1640 entry = ISC_LIST_NEXT(entry, plink);
1641 }
1642
1643 return (NULL);
1644 }
1645
1646 /*
1647 * Entry bucket MUST be locked!
1648 */
1649 static isc_boolean_t
1650 entry_is_bad_for_zone(dns_adb_t *adb, dns_adbentry_t *entry, dns_name_t *zone,
1651 isc_stdtime_t now)
1652 {
1653 dns_adbzoneinfo_t *zi, *next_zi;
1654 isc_boolean_t is_bad;
1655
1656 is_bad = ISC_FALSE;
1657
1658 zi = ISC_LIST_HEAD(entry->zoneinfo);
1659 if (zi == NULL)
1660 return (ISC_FALSE);
1661 while (zi != NULL) {
1662 next_zi = ISC_LIST_NEXT(zi, plink);
1663
1664 /*
1665 * Has the entry expired?
1666 */
1667 if (zi->lame_timer < now) {
1668 ISC_LIST_UNLINK(entry->zoneinfo, zi, plink);
1669 free_adbzoneinfo(adb, &zi);
1670 }
1671
1672 /*
1673 * Order tests from least to most expensive.
1674 */
1675 if (zi != NULL && !is_bad) {
1676 if (dns_name_equal(zone, &zi->zone))
1677 is_bad = ISC_TRUE;
1678 }
1679
1680 zi = next_zi;
1681 }
1682
1683 return (is_bad);
1684 }
1685
1686 static void
1687 copy_namehook_lists(dns_adb_t *adb, dns_adbfind_t *find, dns_name_t *zone,
1688 dns_adbname_t *name, isc_stdtime_t now)
1689 {
1690 dns_adbnamehook_t *namehook;
1691 dns_adbaddrinfo_t *addrinfo;
1692 dns_adbentry_t *entry;
1693 int bucket;
1694
1695 bucket = DNS_ADB_INVALIDBUCKET;
1696
1697 if (find->options & DNS_ADBFIND_INET) {
1698 namehook = ISC_LIST_HEAD(name->v4);
1699 while (namehook != NULL) {
1700 entry = namehook->entry;
1701 bucket = entry->lock_bucket;
1702 LOCK(&adb->entrylocks[bucket]);
1703
1704 if (!FIND_RETURNLAME(find)
1705 && entry_is_bad_for_zone(adb, entry, zone, now)) {
1706 find->options |= DNS_ADBFIND_LAMEPRUNED;
1707 goto nextv4;
1708 }
1709 addrinfo = new_adbaddrinfo(adb, entry, find->port);
1710 if (addrinfo == NULL) {
1711 find->partial_result |= DNS_ADBFIND_INET;
1712 goto out;
1713 }
1714 /*
1715 * Found a valid entry. Add it to the find's list.
1716 */
1717 inc_entry_refcnt(adb, entry, ISC_FALSE);
1718 ISC_LIST_APPEND(find->list, addrinfo, publink);
1719 addrinfo = NULL;
1720 nextv4:
1721 UNLOCK(&adb->entrylocks[bucket]);
1722 bucket = DNS_ADB_INVALIDBUCKET;
1723 namehook = ISC_LIST_NEXT(namehook, plink);
1724 }
1725 }
1726
1727 if (find->options & DNS_ADBFIND_INET6) {
1728 namehook = ISC_LIST_HEAD(name->v6);
1729 while (namehook != NULL) {
1730 entry = namehook->entry;
1731 bucket = entry->lock_bucket;
1732 LOCK(&adb->entrylocks[bucket]);
1733
1734 if (entry_is_bad_for_zone(adb, entry, zone, now))
1735 goto nextv6;
1736 addrinfo = new_adbaddrinfo(adb, entry, find->port);
1737 if (addrinfo == NULL) {
1738 find->partial_result |= DNS_ADBFIND_INET6;
1739 goto out;
1740 }
1741 /*
1742 * Found a valid entry. Add it to the find's list.
1743 */
1744 inc_entry_refcnt(adb, entry, ISC_FALSE);
1745 ISC_LIST_APPEND(find->list, addrinfo, publink);
1746 addrinfo = NULL;
1747 nextv6:
1748 UNLOCK(&adb->entrylocks[bucket]);
1749 bucket = DNS_ADB_INVALIDBUCKET;
1750 namehook = ISC_LIST_NEXT(namehook, plink);
1751 }
1752 }
1753
1754 out:
1755 if (bucket != DNS_ADB_INVALIDBUCKET)
1756 UNLOCK(&adb->entrylocks[bucket]);
1757 }
1758
1759 static void
1760 shutdown_task(isc_task_t *task, isc_event_t *ev) {
1761 dns_adb_t *adb;
1762
1763 UNUSED(task);
1764
1765 adb = ev->ev_arg;
1766 INSIST(DNS_ADB_VALID(adb));
1767
1768 /*
1769 * Kill the timer, and then the ADB itself. Note that this implies
1770 * that this task was the one scheduled to get timer events. If
1771 * this is not true (and it is unfortunate there is no way to INSIST()
1772 * this) badness will occur.
1773 */
1774 LOCK(&adb->lock);
1775 isc_timer_detach(&adb->timer);
1776 UNLOCK(&adb->lock);
1777 isc_event_free(&ev);
1778 destroy(adb);
1779 }
1780
1781 /*
1782 * Name bucket must be locked; adb may be locked; no other locks held.
1783 */
1784 static isc_boolean_t
1785 check_expire_name(dns_adbname_t **namep, isc_stdtime_t now) {
1786 dns_adbname_t *name;
1787 isc_boolean_t result = ISC_FALSE;
1788
1789 INSIST(namep != NULL && DNS_ADBNAME_VALID(*namep));
1790 name = *namep;
1791
1792 if (NAME_HAS_V4(name) || NAME_HAS_V6(name))
1793 return (result);
1794 if (NAME_FETCH(name))
1795 return (result);
1796 if (!EXPIRE_OK(name->expire_v4, now))
1797 return (result);
1798 if (!EXPIRE_OK(name->expire_v6, now))
1799 return (result);
1800 if (!EXPIRE_OK(name->expire_target, now))
1801 return (result);
1802
1803 /*
1804 * The name is empty. Delete it.
1805 */
1806 result = kill_name(&name, DNS_EVENT_ADBEXPIRED);
1807 *namep = NULL;
1808
1809 /*
1810 * Our caller, or one of its callers, will be calling check_exit() at
1811 * some point, so we don't need to do it here.
1812 */
1813 return (result);
1814 }
1815
1816 /*
1817 * Entry bucket must be locked; adb may be locked; no other locks held.
1818 */
1819 static isc_boolean_t
1820 check_expire_entry(dns_adb_t *adb, dns_adbentry_t **entryp, isc_stdtime_t now)
1821 {
1822 dns_adbentry_t *entry;
1823 isc_boolean_t expire;
1824 isc_boolean_t result = ISC_FALSE;
1825
1826 INSIST(entryp != NULL && DNS_ADBENTRY_VALID(*entryp));
1827 entry = *entryp;
1828
1829 if (entry->refcnt != 0)
1830 return (result);
1831
1832 if (adb->overmem) {
1833 isc_uint32_t val;
1834
1835 isc_random_get(&val);
1836
1837 expire = ISC_TF((val % 4) == 0);
1838 } else
1839 expire = ISC_FALSE;
1840
1841 if (entry->expires == 0 || (! expire && entry->expires > now))
1842 return (result);
1843
1844 /*
1845 * The entry is not in use. Delete it.
1846 */
1847 DP(DEF_LEVEL, "killing entry %p", entry);
1848 INSIST(ISC_LINK_LINKED(entry, plink));
1849 result = unlink_entry(adb, entry);
1850 free_adbentry(adb, &entry);
1851 if (result)
1852 dec_adb_irefcnt(adb);
1853 *entryp = NULL;
1854 return (result);
1855 }
1856
1857 /*
1858 * ADB must be locked, and no other locks held.
1859 */
1860 static isc_boolean_t
1861 cleanup_names(dns_adb_t *adb, int bucket, isc_stdtime_t now) {
1862 dns_adbname_t *name;
1863 dns_adbname_t *next_name;
1864 isc_boolean_t result = ISC_FALSE;
1865
1866 DP(CLEAN_LEVEL, "cleaning name bucket %d", bucket);
1867
1868 LOCK(&adb->namelocks[bucket]);
1869 if (adb->name_sd[bucket]) {
1870 UNLOCK(&adb->namelocks[bucket]);
1871 return (result);
1872 }
1873
1874 name = ISC_LIST_HEAD(adb->names[bucket]);
1875 while (name != NULL) {
1876 next_name = ISC_LIST_NEXT(name, plink);
1877 INSIST(result == ISC_FALSE);
1878 result = check_expire_namehooks(name, now, adb->overmem);
1879 if (!result)
1880 result = check_expire_name(&name, now);
1881 name = next_name;
1882 }
1883 UNLOCK(&adb->namelocks[bucket]);
1884 return (result);
1885 }
1886
1887 /*
1888 * ADB must be locked, and no other locks held.
1889 */
1890 static isc_boolean_t
1891 cleanup_entries(dns_adb_t *adb, int bucket, isc_stdtime_t now) {
1892 dns_adbentry_t *entry, *next_entry;
1893 isc_boolean_t result = ISC_FALSE;
1894
1895 DP(CLEAN_LEVEL, "cleaning entry bucket %d", bucket);
1896
1897 LOCK(&adb->entrylocks[bucket]);
1898 entry = ISC_LIST_HEAD(adb->entries[bucket]);
1899 while (entry != NULL) {
1900 next_entry = ISC_LIST_NEXT(entry, plink);
1901 INSIST(result == ISC_FALSE);
1902 result = check_expire_entry(adb, &entry, now);
1903 entry = next_entry;
1904 }
1905 UNLOCK(&adb->entrylocks[bucket]);
1906 return (result);
1907 }
1908
1909 static void
1910 timer_cleanup(isc_task_t *task, isc_event_t *ev) {
1911 dns_adb_t *adb;
1912 isc_stdtime_t now;
1913 unsigned int i;
1914 isc_interval_t interval;
1915
1916 UNUSED(task);
1917
1918 adb = ev->ev_arg;
1919 INSIST(DNS_ADB_VALID(adb));
1920
1921 LOCK(&adb->lock);
1922
1923 isc_stdtime_get(&now);
1924
1925 for (i = 0; i < CLEAN_BUCKETS; i++) {
1926 /*
1927 * Call our cleanup routines.
1928 */
1929 RUNTIME_CHECK(cleanup_names(adb, adb->next_cleanbucket, now) ==
1930 ISC_FALSE);
1931 RUNTIME_CHECK(cleanup_entries(adb, adb->next_cleanbucket, now)
1932 == ISC_FALSE);
1933
1934 /*
1935 * Set the next bucket to be cleaned.
1936 */
1937 adb->next_cleanbucket++;
1938 if (adb->next_cleanbucket >= NBUCKETS) {
1939 adb->next_cleanbucket = 0;
1940 #ifdef DUMP_ADB_AFTER_CLEANING
1941 dump_adb(adb, stdout, ISC_TRUE, now);
1942 #endif
1943 }
1944 }
1945
1946 /*
1947 * Reset the timer.
1948 * XXXDCL isc_timer_reset might return ISC_R_UNEXPECTED or
1949 * ISC_R_NOMEMORY, but it isn't clear what could be done here
1950 * if either one of those things happened.
1951 */
1952 interval = adb->tick_interval;
1953 if (adb->overmem)
1954 isc_interval_set(&interval, 0, 1);
1955 (void)isc_timer_reset(adb->timer, isc_timertype_once, NULL,
1956 &interval, ISC_FALSE);
1957
1958 UNLOCK(&adb->lock);
1959
1960 isc_event_free(&ev);
1961 }
1962
1963 static void
1964 destroy(dns_adb_t *adb) {
1965 adb->magic = 0;
1966
1967 /*
1968 * The timer is already dead, from the task's shutdown callback.
1969 */
1970 isc_task_detach(&adb->task);
1971
1972 isc_mempool_destroy(&adb->nmp);
1973 isc_mempool_destroy(&adb->nhmp);
1974 isc_mempool_destroy(&adb->zimp);
1975 isc_mempool_destroy(&adb->emp);
1976 isc_mempool_destroy(&adb->ahmp);
1977 isc_mempool_destroy(&adb->aimp);
1978 isc_mempool_destroy(&adb->afmp);
1979
1980 DESTROYMUTEXBLOCK(adb->entrylocks, NBUCKETS);
1981 DESTROYMUTEXBLOCK(adb->namelocks, NBUCKETS);
1982
1983 DESTROYLOCK(&adb->reflock);
1984 DESTROYLOCK(&adb->lock);
1985 DESTROYLOCK(&adb->mplock);
1986
1987 isc_mem_putanddetach(&adb->mctx, adb, sizeof(dns_adb_t));
1988 }
1989
1990
1991 /*
1992 * Public functions.
1993 */
1994
1995 isc_result_t
1996 dns_adb_create(isc_mem_t *mem, dns_view_t *view, isc_timermgr_t *timermgr,
1997 isc_taskmgr_t *taskmgr, dns_adb_t **newadb)
1998 {
1999 dns_adb_t *adb;
2000 isc_result_t result;
2001 int i;
2002
2003 REQUIRE(mem != NULL);
2004 REQUIRE(view != NULL);
2005 REQUIRE(timermgr != NULL);
2006 REQUIRE(taskmgr != NULL);
2007 REQUIRE(newadb != NULL && *newadb == NULL);
2008
2009 adb = isc_mem_get(mem, sizeof(dns_adb_t));
2010 if (adb == NULL)
2011 return (ISC_R_NOMEMORY);
2012
2013 /*
2014 * Initialize things here that cannot fail, and especially things
2015 * that must be NULL for the error return to work properly.
2016 */
2017 adb->magic = 0;
2018 adb->erefcnt = 1;
2019 adb->irefcnt = 0;
2020 adb->nmp = NULL;
2021 adb->nhmp = NULL;
2022 adb->zimp = NULL;
2023 adb->emp = NULL;
2024 adb->ahmp = NULL;
2025 adb->aimp = NULL;
2026 adb->afmp = NULL;
2027 adb->task = NULL;
2028 adb->timer = NULL;
2029 adb->mctx = NULL;
2030 adb->view = view;
2031 adb->timermgr = timermgr;
2032 adb->taskmgr = taskmgr;
2033 adb->next_cleanbucket = 0;
2034 ISC_EVENT_INIT(&adb->cevent, sizeof(adb->cevent), 0, NULL,
2035 DNS_EVENT_ADBCONTROL, shutdown_task, adb,
2036 adb, NULL, NULL);
2037 adb->cevent_sent = ISC_FALSE;
2038 adb->shutting_down = ISC_FALSE;
2039 adb->overmem = ISC_FALSE;
2040 ISC_LIST_INIT(adb->whenshutdown);
2041
2042 isc_mem_attach(mem, &adb->mctx);
2043
2044 result = isc_mutex_init(&adb->lock);
2045 if (result != ISC_R_SUCCESS)
2046 goto fail0b;
2047
2048 result = isc_mutex_init(&adb->mplock);
2049 if (result != ISC_R_SUCCESS)
2050 goto fail0c;
2051
2052 result = isc_mutex_init(&adb->reflock);
2053 if (result != ISC_R_SUCCESS)
2054 goto fail0d;
2055
2056 /*
2057 * Initialize the bucket locks for names and elements.
2058 * May as well initialize the list heads, too.
2059 */
2060 result = isc_mutexblock_init(adb->namelocks, NBUCKETS);
2061 if (result != ISC_R_SUCCESS)
2062 goto fail1;
2063 for (i = 0; i < NBUCKETS; i++) {
2064 ISC_LIST_INIT(adb->names[i]);
2065 adb->name_sd[i] = ISC_FALSE;
2066 adb->name_refcnt[i] = 0;
2067 adb->irefcnt++;
2068 }
2069 for (i = 0; i < NBUCKETS; i++) {
2070 ISC_LIST_INIT(adb->entries[i]);
2071 adb->entry_sd[i] = ISC_FALSE;
2072 adb->entry_refcnt[i] = 0;
2073 adb->irefcnt++;
2074 }
2075 result = isc_mutexblock_init(adb->entrylocks, NBUCKETS);
2076 if (result != ISC_R_SUCCESS)
2077 goto fail2;
2078
2079 /*
2080 * Memory pools
2081 */
2082 #define MPINIT(t, p, n) do { \
2083 result = isc_mempool_create(mem, sizeof(t), &(p)); \
2084 if (result != ISC_R_SUCCESS) \
2085 goto fail3; \
2086 isc_mempool_setfreemax((p), FREE_ITEMS); \
2087 isc_mempool_setfillcount((p), FILL_COUNT); \
2088 isc_mempool_setname((p), n); \
2089 isc_mempool_associatelock((p), &adb->mplock); \
2090 } while (0)
2091
2092 MPINIT(dns_adbname_t, adb->nmp, "adbname");
2093 MPINIT(dns_adbnamehook_t, adb->nhmp, "adbnamehook");
2094 MPINIT(dns_adbzoneinfo_t, adb->zimp, "adbzoneinfo");
2095 MPINIT(dns_adbentry_t, adb->emp, "adbentry");
2096 MPINIT(dns_adbfind_t, adb->ahmp, "adbfind");
2097 MPINIT(dns_adbaddrinfo_t, adb->aimp, "adbaddrinfo");
2098 MPINIT(dns_adbfetch_t, adb->afmp, "adbfetch");
2099
2100 #undef MPINIT
2101
2102 /*
2103 * Allocate a timer and a task for our periodic cleanup.
2104 */
2105 result = isc_task_create(adb->taskmgr, 0, &adb->task);
2106 if (result != ISC_R_SUCCESS)
2107 goto fail3;
2108 isc_task_setname(adb->task, "ADB", adb);
2109 /*
2110 * XXXMLG When this is changed to be a config file option,
2111 */
2112 isc_interval_set(&adb->tick_interval, CLEAN_SECONDS, 0);
2113 result = isc_timer_create(adb->timermgr, isc_timertype_once,
2114 NULL, &adb->tick_interval, adb->task,
2115 timer_cleanup, adb, &adb->timer);
2116 if (result != ISC_R_SUCCESS)
2117 goto fail3;
2118
2119 DP(ISC_LOG_DEBUG(5), "cleaning interval for adb: "
2120 "%u buckets every %u seconds, %u buckets in system, %u cl.interval",
2121 CLEAN_BUCKETS, CLEAN_SECONDS, NBUCKETS, CLEAN_PERIOD);
2122
2123 /*
2124 * Normal return.
2125 */
2126 adb->magic = DNS_ADB_MAGIC;
2127 *newadb = adb;
2128 return (ISC_R_SUCCESS);
2129
2130 fail3:
2131 if (adb->task != NULL)
2132 isc_task_detach(&adb->task);
2133 if (adb->timer != NULL)
2134 isc_timer_detach(&adb->timer);
2135
2136 /* clean up entrylocks */
2137 DESTROYMUTEXBLOCK(adb->entrylocks, NBUCKETS);
2138
2139 fail2: /* clean up namelocks */
2140 DESTROYMUTEXBLOCK(adb->namelocks, NBUCKETS);
2141
2142 fail1: /* clean up only allocated memory */
2143 if (adb->nmp != NULL)
2144 isc_mempool_destroy(&adb->nmp);
2145 if (adb->nhmp != NULL)
2146 isc_mempool_destroy(&adb->nhmp);
2147 if (adb->zimp != NULL)
2148 isc_mempool_destroy(&adb->zimp);
2149 if (adb->emp != NULL)
2150 isc_mempool_destroy(&adb->emp);
2151 if (adb->ahmp != NULL)
2152 isc_mempool_destroy(&adb->ahmp);
2153 if (adb->aimp != NULL)
2154 isc_mempool_destroy(&adb->aimp);
2155 if (adb->afmp != NULL)
2156 isc_mempool_destroy(&adb->afmp);
2157
2158 DESTROYLOCK(&adb->reflock);
2159 fail0d:
2160 DESTROYLOCK(&adb->mplock);
2161 fail0c:
2162 DESTROYLOCK(&adb->lock);
2163 fail0b:
2164 isc_mem_putanddetach(&adb->mctx, adb, sizeof(dns_adb_t));
2165
2166 return (result);
2167 }
2168
2169 void
2170 dns_adb_attach(dns_adb_t *adb, dns_adb_t **adbx) {
2171
2172 REQUIRE(DNS_ADB_VALID(adb));
2173 REQUIRE(adbx != NULL && *adbx == NULL);
2174
2175 inc_adb_erefcnt(adb);
2176 *adbx = adb;
2177 }
2178
2179 void
2180 dns_adb_detach(dns_adb_t **adbx) {
2181 dns_adb_t *adb;
2182 isc_boolean_t need_exit_check;
2183
2184 REQUIRE(adbx != NULL && DNS_ADB_VALID(*adbx));
2185
2186 adb = *adbx;
2187 *adbx = NULL;
2188
2189 INSIST(adb->erefcnt > 0);
2190
2191 LOCK(&adb->reflock);
2192 adb->erefcnt--;
2193 need_exit_check = ISC_TF(adb->erefcnt == 0 && adb->irefcnt == 0);
2194 UNLOCK(&adb->reflock);
2195
2196 if (need_exit_check) {
2197 LOCK(&adb->lock);
2198 INSIST(adb->shutting_down);
2199 check_exit(adb);
2200 UNLOCK(&adb->lock);
2201 }
2202 }
2203
2204 void
2205 dns_adb_whenshutdown(dns_adb_t *adb, isc_task_t *task, isc_event_t **eventp) {
2206 isc_task_t *clone;
2207 isc_event_t *event;
2208 isc_boolean_t zeroirefcnt = ISC_FALSE;
2209
2210 /*
2211 * Send '*eventp' to 'task' when 'adb' has shutdown.
2212 */
2213
2214 REQUIRE(DNS_ADB_VALID(adb));
2215 REQUIRE(eventp != NULL);
2216
2217 event = *eventp;
2218 *eventp = NULL;
2219
2220 LOCK(&adb->lock);
2221
2222 LOCK(&adb->reflock);
2223 zeroirefcnt = ISC_TF(adb->irefcnt == 0);
2224
2225 if (adb->shutting_down && zeroirefcnt &&
2226 isc_mempool_getallocated(adb->ahmp) == 0) {
2227 /*
2228 * We're already shutdown. Send the event.
2229 */
2230 event->ev_sender = adb;
2231 isc_task_send(task, &event);
2232 } else {
2233 clone = NULL;
2234 isc_task_attach(task, &clone);
2235 event->ev_sender = clone;
2236 ISC_LIST_APPEND(adb->whenshutdown, event, ev_link);
2237 }
2238
2239 UNLOCK(&adb->reflock);
2240 UNLOCK(&adb->lock);
2241 }
2242
2243 void
2244 dns_adb_shutdown(dns_adb_t *adb) {
2245 isc_boolean_t need_check_exit;
2246
2247 /*
2248 * Shutdown 'adb'.
2249 */
2250
2251 LOCK(&adb->lock);
2252
2253 if (!adb->shutting_down) {
2254 adb->shutting_down = ISC_TRUE;
2255 isc_mem_setwater(adb->mctx, water, adb, 0, 0);
2256 need_check_exit = shutdown_names(adb);
2257 if (!need_check_exit)
2258 need_check_exit = shutdown_entries(adb);
2259 if (need_check_exit)
2260 check_exit(adb);
2261 }
2262
2263 UNLOCK(&adb->lock);
2264 }
2265
2266 isc_result_t
2267 dns_adb_createfind(dns_adb_t *adb, isc_task_t *task, isc_taskaction_t action,
2268 void *arg, dns_name_t *name, dns_name_t *zone,
2269 unsigned int options, isc_stdtime_t now, dns_name_t *target,
2270 in_port_t port, dns_adbfind_t **findp)
2271 {
2272 dns_adbfind_t *find;
2273 dns_adbname_t *adbname;
2274 int bucket;
2275 isc_boolean_t want_event, start_at_zone, alias, have_address;
2276 isc_result_t result;
2277 unsigned int wanted_addresses;
2278 unsigned int wanted_fetches;
2279 unsigned int query_pending;
2280
2281 REQUIRE(DNS_ADB_VALID(adb));
2282 if (task != NULL) {
2283 REQUIRE(action != NULL);
2284 }
2285 REQUIRE(name != NULL);
2286 REQUIRE(zone != NULL);
2287 REQUIRE(findp != NULL && *findp == NULL);
2288 REQUIRE(target == NULL || dns_name_hasbuffer(target));
2289
2290 REQUIRE((options & DNS_ADBFIND_ADDRESSMASK) != 0);
2291
2292 result = ISC_R_UNEXPECTED;
2293 wanted_addresses = (options & DNS_ADBFIND_ADDRESSMASK);
2294 wanted_fetches = 0;
2295 query_pending = 0;
2296 want_event = ISC_FALSE;
2297 start_at_zone = ISC_FALSE;
2298 alias = ISC_FALSE;
2299
2300 if (now == 0)
2301 isc_stdtime_get(&now);
2302
2303 /*
2304 * XXXMLG Move this comment somewhere else!
2305 *
2306 * Look up the name in our internal database.
2307 *
2308 * Possibilities: Note that these are not always exclusive.
2309 *
2310 * No name found. In this case, allocate a new name header and
2311 * an initial namehook or two. If any of these allocations
2312 * fail, clean up and return ISC_R_NOMEMORY.
2313 *
2314 * Name found, valid addresses present. Allocate one addrinfo
2315 * structure for each found and append it to the linked list
2316 * of addresses for this header.
2317 *
2318 * Name found, queries pending. In this case, if a task was
2319 * passed in, allocate a job id, attach it to the name's job
2320 * list and remember to tell the caller that there will be
2321 * more info coming later.
2322 */
2323
2324 find = new_adbfind(adb);
2325 if (find == NULL)
2326 return (ISC_R_NOMEMORY);
2327
2328 find->port = port;
2329
2330 /*
2331 * Remember what types of addresses we are interested in.
2332 */
2333 find->options = options;
2334 find->flags |= wanted_addresses;
2335 if (FIND_WANTEVENT(find)) {
2336 REQUIRE(task != NULL);
2337 }
2338
2339 /*
2340 * Try to see if we know anything about this name at all.
2341 */
2342 bucket = DNS_ADB_INVALIDBUCKET;
2343 adbname = find_name_and_lock(adb, name, find->options, &bucket);
2344 if (adb->name_sd[bucket]) {
2345 DP(DEF_LEVEL,
2346 "dns_adb_createfind: returning ISC_R_SHUTTINGDOWN");
2347 RUNTIME_CHECK(free_adbfind(adb, &find) == ISC_FALSE);
2348 result = ISC_R_SHUTTINGDOWN;
2349 goto out;
2350 }
2351
2352 /*
2353 * Nothing found. Allocate a new adbname structure for this name.
2354 */
2355 if (adbname == NULL) {
2356 adbname = new_adbname(adb, name);
2357 if (adbname == NULL) {
2358 RUNTIME_CHECK(free_adbfind(adb, &find) == ISC_FALSE);
2359 result = ISC_R_NOMEMORY;
2360 goto out;
2361 }
2362 link_name(adb, bucket, adbname);
2363 if (FIND_HINTOK(find))
2364 adbname->flags |= NAME_HINT_OK;
2365 if (FIND_GLUEOK(find))
2366 adbname->flags |= NAME_GLUE_OK;
2367 if (FIND_STARTATZONE(find))
2368 adbname->flags |= NAME_STARTATZONE;
2369 }
2370
2371 /*
2372 * Expire old entries, etc.
2373 */
2374 RUNTIME_CHECK(check_expire_namehooks(adbname, now, adb->overmem) ==
2375 ISC_FALSE);
2376
2377 /*
2378 * Do we know that the name is an alias?
2379 */
2380 if (!EXPIRE_OK(adbname->expire_target, now)) {
2381 /*
2382 * Yes, it is.
2383 */
2384 DP(DEF_LEVEL,
2385 "dns_adb_createfind: name %p is an alias (cached)",
2386 adbname);
2387 alias = ISC_TRUE;
2388 goto post_copy;
2389 }
2390
2391 /*
2392 * Try to populate the name from the database and/or
2393 * start fetches. First try looking for an A record
2394 * in the database.
2395 */
2396 if (!NAME_HAS_V4(adbname) && EXPIRE_OK(adbname->expire_v4, now)
2397 && WANT_INET(wanted_addresses)) {
2398 result = dbfind_name(adbname, now, dns_rdatatype_a);
2399 if (result == ISC_R_SUCCESS) {
2400 DP(DEF_LEVEL,
2401 "dns_adb_createfind: found A for name %p in db",
2402 adbname);
2403 goto v6;
2404 }
2405
2406 /*
2407 * Did we get a CNAME or DNAME?
2408 */
2409 if (result == DNS_R_ALIAS) {
2410 DP(DEF_LEVEL,
2411 "dns_adb_createfind: name %p is an alias",
2412 adbname);
2413 alias = ISC_TRUE;
2414 goto post_copy;
2415 }
2416
2417 /*
2418 * If the name doesn't exist at all, don't bother with
2419 * v6 queries; they won't work.
2420 *
2421 * If the name does exist but we didn't get our data, go
2422 * ahead and try AAAA.
2423 *
2424 * If the result is neither of these, try a fetch for A.
2425 */
2426 if (NXDOMAIN_RESULT(result))
2427 goto fetch;
2428 else if (NXRRSET_RESULT(result))
2429 goto v6;
2430
2431 if (!NAME_FETCH_V4(adbname))
2432 wanted_fetches |= DNS_ADBFIND_INET;
2433 }
2434
2435 v6:
2436 if (!NAME_HAS_V6(adbname) && EXPIRE_OK(adbname->expire_v6, now)
2437 && WANT_INET6(wanted_addresses)) {
2438 result = dbfind_name(adbname, now, dns_rdatatype_aaaa);
2439 if (result == ISC_R_SUCCESS) {
2440 DP(DEF_LEVEL,
2441 "dns_adb_createfind: found AAAA for name %p",
2442 adbname);
2443 goto fetch;
2444 }
2445
2446 /*
2447 * Did we get a CNAME or DNAME?
2448 */
2449 if (result == DNS_R_ALIAS) {
2450 DP(DEF_LEVEL,
2451 "dns_adb_createfind: name %p is an alias",
2452 adbname);
2453 alias = ISC_TRUE;
2454 goto post_copy;
2455 }
2456
2457 /*
2458 * Listen to negative cache hints, and don't start
2459 * another query.
2460 */
2461 if (NCACHE_RESULT(result) || AUTH_NX(result))
2462 goto fetch;
2463
2464 if (!NAME_FETCH_V6(adbname))
2465 wanted_fetches |= DNS_ADBFIND_INET6;
2466 }
2467
2468 fetch:
2469 if ((WANT_INET(wanted_addresses) && NAME_HAS_V4(adbname)) ||
2470 (WANT_INET6(wanted_addresses) && NAME_HAS_V6(adbname)))
2471 have_address = ISC_TRUE;
2472 else
2473 have_address = ISC_FALSE;
2474 if (wanted_fetches != 0 &&
2475 ! (FIND_AVOIDFETCHES(find) && have_address)) {
2476 /*
2477 * We're missing at least one address family. Either the
2478 * caller hasn't instructed us to avoid fetches, or we don't
2479 * know anything about any of the address families that would
2480 * be acceptable so we have to launch fetches.
2481 */
2482
2483 if (FIND_STARTATZONE(find))
2484 start_at_zone = ISC_TRUE;
2485
2486 /*
2487 * Start V4.
2488 */
2489 if (WANT_INET(wanted_fetches) &&
2490 fetch_name(adbname, start_at_zone,
2491 dns_rdatatype_a) == ISC_R_SUCCESS) {
2492 DP(DEF_LEVEL,
2493 "dns_adb_createfind: started A fetch for name %p",
2494 adbname);
2495 }
2496
2497 /*
2498 * Start V6.
2499 */
2500 if (WANT_INET6(wanted_fetches) &&
2501 fetch_name(adbname, start_at_zone,
2502 dns_rdatatype_aaaa) == ISC_R_SUCCESS) {
2503 DP(DEF_LEVEL,
2504 "dns_adb_createfind: "
2505 "started AAAA fetch for name %p",
2506 adbname);
2507 }
2508 }
2509
2510 /*
2511 * Run through the name and copy out the bits we are
2512 * interested in.
2513 */
2514 copy_namehook_lists(adb, find, zone, adbname, now);
2515
2516 post_copy:
2517 if (NAME_FETCH_V4(adbname))
2518 query_pending |= DNS_ADBFIND_INET;
2519 if (NAME_FETCH_V6(adbname))
2520 query_pending |= DNS_ADBFIND_INET6;
2521
2522 /*
2523 * Attach to the name's query list if there are queries
2524 * already running, and we have been asked to.
2525 */
2526 want_event = ISC_TRUE;
2527 if (!FIND_WANTEVENT(find))
2528 want_event = ISC_FALSE;
2529 if (FIND_WANTEMPTYEVENT(find) && FIND_HAS_ADDRS(find))
2530 want_event = ISC_FALSE;
2531 if ((wanted_addresses & query_pending) == 0)
2532 want_event = ISC_FALSE;
2533 if (alias)
2534 want_event = ISC_FALSE;
2535 if (want_event) {
2536 find->adbname = adbname;
2537 find->name_bucket = bucket;
2538 ISC_LIST_APPEND(adbname->finds, find, plink);
2539 find->query_pending = (query_pending & wanted_addresses);
2540 find->flags &= ~DNS_ADBFIND_ADDRESSMASK;
2541 find->flags |= (find->query_pending & DNS_ADBFIND_ADDRESSMASK);
2542 DP(DEF_LEVEL, "createfind: attaching find %p to adbname %p",
2543 find, adbname);
2544 } else {
2545 /*
2546 * Remove the flag so the caller knows there will never
2547 * be an event, and set internal flags to fake that
2548 * the event was sent and freed, so dns_adb_destroyfind() will
2549 * do the right thing.
2550 */
2551 find->query_pending = (query_pending & wanted_addresses);
2552 find->options &= ~DNS_ADBFIND_WANTEVENT;
2553 find->flags |= (FIND_EVENT_SENT | FIND_EVENT_FREED);
2554 find->flags &= ~DNS_ADBFIND_ADDRESSMASK;
2555 }
2556
2557 find->partial_result |= (adbname->partial_result & wanted_addresses);
2558 if (alias) {
2559 if (target != NULL) {
2560 result = dns_name_copy(&adbname->target, target, NULL);
2561 if (result != ISC_R_SUCCESS)
2562 goto out;
2563 }
2564 result = DNS_R_ALIAS;
2565 } else
2566 result = ISC_R_SUCCESS;
2567
2568 /*
2569 * Copy out error flags from the name structure into the find.
2570 */
2571 find->result_v4 = find_err_map[adbname->fetch_err];
2572 find->result_v6 = find_err_map[adbname->fetch6_err];
2573
2574 out:
2575 if (find != NULL) {
2576 *findp = find;
2577
2578 if (want_event) {
2579 isc_task_t *taskp;
2580
2581 INSIST((find->flags & DNS_ADBFIND_ADDRESSMASK) != 0);
2582 taskp = NULL;
2583 isc_task_attach(task, &taskp);
2584 find->event.ev_sender = taskp;
2585 find->event.ev_action = action;
2586 find->event.ev_arg = arg;
2587 }
2588 }
2589
2590 UNLOCK(&adb->namelocks[bucket]);
2591
2592 return (result);
2593 }
2594
2595 void
2596 dns_adb_destroyfind(dns_adbfind_t **findp) {
2597 dns_adbfind_t *find;
2598 dns_adbentry_t *entry;
2599 dns_adbaddrinfo_t *ai;
2600 int bucket;
2601 dns_adb_t *adb;
2602
2603 REQUIRE(findp != NULL && DNS_ADBFIND_VALID(*findp));
2604 find = *findp;
2605 *findp = NULL;
2606
2607 LOCK(&find->lock);
2608
2609 DP(DEF_LEVEL, "dns_adb_destroyfind on find %p", find);
2610
2611 adb = find->adb;
2612 REQUIRE(DNS_ADB_VALID(adb));
2613
2614 REQUIRE(FIND_EVENTFREED(find));
2615
2616 bucket = find->name_bucket;
2617 INSIST(bucket == DNS_ADB_INVALIDBUCKET);
2618
2619 UNLOCK(&find->lock);
2620
2621 /*
2622 * The find doesn't exist on any list, and nothing is locked.
2623 * Return the find to the memory pool, and decrement the adb's
2624 * reference count.
2625 */
2626 ai = ISC_LIST_HEAD(find->list);
2627 while (ai != NULL) {
2628 ISC_LIST_UNLINK(find->list, ai, publink);
2629 entry = ai->entry;
2630 ai->entry = NULL;
2631 INSIST(DNS_ADBENTRY_VALID(entry));
2632 RUNTIME_CHECK(dec_entry_refcnt(adb, entry, ISC_TRUE) ==
2633 ISC_FALSE);
2634 free_adbaddrinfo(adb, &ai);
2635 ai = ISC_LIST_HEAD(find->list);
2636 }
2637
2638 /*
2639 * WARNING: The find is freed with the adb locked. This is done
2640 * to avoid a race condition where we free the find, some other
2641 * thread tests to see if it should be destroyed, detects it should
2642 * be, destroys it, and then we try to lock it for our check, but the
2643 * lock is destroyed.
2644 */
2645 LOCK(&adb->lock);
2646 if (free_adbfind(adb, &find))
2647 check_exit(adb);
2648 UNLOCK(&adb->lock);
2649 }
2650
2651 void
2652 dns_adb_cancelfind(dns_adbfind_t *find) {
2653 isc_event_t *ev;
2654 isc_task_t *task;
2655 dns_adb_t *adb;
2656 int bucket;
2657 int unlock_bucket;
2658
2659 LOCK(&find->lock);
2660
2661 DP(DEF_LEVEL, "dns_adb_cancelfind on find %p", find);
2662
2663 adb = find->adb;
2664 REQUIRE(DNS_ADB_VALID(adb));
2665
2666 REQUIRE(!FIND_EVENTFREED(find));
2667 REQUIRE(FIND_WANTEVENT(find));
2668
2669 bucket = find->name_bucket;
2670 if (bucket == DNS_ADB_INVALIDBUCKET)
2671 goto cleanup;
2672
2673 /*
2674 * We need to get the adbname's lock to unlink the find.
2675 */
2676 unlock_bucket = bucket;
2677 violate_locking_hierarchy(&find->lock, &adb->namelocks[unlock_bucket]);
2678 bucket = find->name_bucket;
2679 if (bucket != DNS_ADB_INVALIDBUCKET) {
2680 ISC_LIST_UNLINK(find->adbname->finds, find, plink);
2681 find->adbname = NULL;
2682 find->name_bucket = DNS_ADB_INVALIDBUCKET;
2683 }
2684 UNLOCK(&adb->namelocks[unlock_bucket]);
2685 bucket = DNS_ADB_INVALIDBUCKET;
2686
2687 cleanup:
2688
2689 if (!FIND_EVENTSENT(find)) {
2690 ev = &find->event;
2691 task = ev->ev_sender;
2692 ev->ev_sender = find;
2693 ev->ev_type = DNS_EVENT_ADBCANCELED;
2694 ev->ev_destroy = event_free;
2695 ev->ev_destroy_arg = find;
2696 find->result_v4 = ISC_R_CANCELED;
2697 find->result_v6 = ISC_R_CANCELED;
2698
2699 DP(DEF_LEVEL, "sending event %p to task %p for find %p",
2700 ev, task, find);
2701
2702 isc_task_sendanddetach(&task, (isc_event_t **)&ev);
2703 }
2704
2705 UNLOCK(&find->lock);
2706 }
2707
2708 void
2709 dns_adb_dump(dns_adb_t *adb, FILE *f) {
2710 int i;
2711 isc_stdtime_t now;
2712
2713 REQUIRE(DNS_ADB_VALID(adb));
2714 REQUIRE(f != NULL);
2715
2716 /*
2717 * Lock the adb itself, lock all the name buckets, then lock all
2718 * the entry buckets. This should put the adb into a state where
2719 * nothing can change, so we can iterate through everything and
2720 * print at our leisure.
2721 */
2722
2723 LOCK(&adb->lock);
2724 isc_stdtime_get(&now);
2725
2726 for (i = 0; i < NBUCKETS; i++)
2727 RUNTIME_CHECK(cleanup_names(adb, i, now) == ISC_FALSE);
2728 for (i = 0; i < NBUCKETS; i++)
2729 RUNTIME_CHECK(cleanup_entries(adb, i, now) == ISC_FALSE);
2730
2731 dump_adb(adb, f, ISC_FALSE, now);
2732 UNLOCK(&adb->lock);
2733 }
2734
2735 static void
2736 dump_ttl(FILE *f, const char *legend, isc_stdtime_t value, isc_stdtime_t now) {
2737 if (value == INT_MAX)
2738 return;
2739 fprintf(f, " [%s TTL %d]", legend, value - now);
2740 }
2741
2742 static void
2743 dump_adb(dns_adb_t *adb, FILE *f, isc_boolean_t debug, isc_stdtime_t now) {
2744 int i;
2745 dns_adbname_t *name;
2746 dns_adbentry_t *entry;
2747
2748 fprintf(f, ";\n; Address database dump\n;\n");
2749 if (debug)
2750 fprintf(f, "; addr %p, erefcnt %u, irefcnt %u, finds out %u\n",
2751 adb, adb->erefcnt, adb->irefcnt,
2752 isc_mempool_getallocated(adb->nhmp));
2753
2754 for (i = 0; i < NBUCKETS; i++)
2755 LOCK(&adb->namelocks[i]);
2756 for (i = 0; i < NBUCKETS; i++)
2757 LOCK(&adb->entrylocks[i]);
2758
2759 /*
2760 * Dump the names
2761 */
2762 for (i = 0; i < NBUCKETS; i++) {
2763 name = ISC_LIST_HEAD(adb->names[i]);
2764 if (name == NULL)
2765 continue;
2766 if (debug)
2767 fprintf(f, "; bucket %d\n", i);
2768 for (;
2769 name != NULL;
2770 name = ISC_LIST_NEXT(name, plink))
2771 {
2772 if (debug)
2773 fprintf(f, "; name %p (flags %08x)\n",
2774 name, name->flags);
2775
2776 fprintf(f, "; ");
2777 print_dns_name(f, &name->name);
2778 if (dns_name_countlabels(&name->target) > 0) {
2779 fprintf(f, " alias ");
2780 print_dns_name(f, &name->target);
2781 }
2782
2783 dump_ttl(f, "v4", name->expire_v4, now);
2784 dump_ttl(f, "v6", name->expire_v6, now);
2785 dump_ttl(f, "target", name->expire_target, now);
2786
2787 fprintf(f, " [v4 %s] [v6 %s]",
2788 errnames[name->fetch_err],
2789 errnames[name->fetch6_err]);
2790
2791 fprintf(f, "\n");
2792
2793 print_namehook_list(f, "v4", &name->v4, debug, now);
2794 print_namehook_list(f, "v6", &name->v6, debug, now);
2795
2796 if (debug)
2797 print_fetch_list(f, name);
2798 if (debug)
2799 print_find_list(f, name);
2800
2801 }
2802 }
2803
2804 fprintf(f, ";\n; Unassociated entries\n;\n");
2805
2806 for (i = 0; i < NBUCKETS; i++) {
2807 entry = ISC_LIST_HEAD(adb->entries[i]);
2808 while (entry != NULL) {
2809 if (entry->refcnt == 0)
2810 dump_entry(f, entry, debug, now);
2811 entry = ISC_LIST_NEXT(entry, plink);
2812 }
2813 }
2814
2815 /*
2816 * Unlock everything
2817 */
2818 for (i = 0; i < NBUCKETS; i++)
2819 UNLOCK(&adb->entrylocks[i]);
2820 for (i = 0; i < NBUCKETS; i++)
2821 UNLOCK(&adb->namelocks[i]);
2822 }
2823
2824 static void
2825 dump_entry(FILE *f, dns_adbentry_t *entry, isc_boolean_t debug,
2826 isc_stdtime_t now)
2827 {
2828 char addrbuf[ISC_NETADDR_FORMATSIZE];
2829 isc_netaddr_t netaddr;
2830 dns_adbzoneinfo_t *zi;
2831
2832 isc_netaddr_fromsockaddr(&netaddr, &entry->sockaddr);
2833 isc_netaddr_format(&netaddr, addrbuf, sizeof(addrbuf));
2834
2835 if (debug)
2836 fprintf(f, ";\t%p: refcnt %u\n", entry, entry->refcnt);
2837
2838 fprintf(f, ";\t%s [srtt %u] [flags %08x]",
2839 addrbuf, entry->srtt, entry->flags);
2840 if (entry->expires != 0)
2841 fprintf(f, " [ttl %d]", entry->expires - now);
2842 fprintf(f, "\n");
2843 for (zi = ISC_LIST_HEAD(entry->zoneinfo);
2844 zi != NULL;
2845 zi = ISC_LIST_NEXT(zi, plink)) {
2846 fprintf(f, ";\t\t");
2847 print_dns_name(f, &zi->zone);
2848 fprintf(f, " [lame TTL %d]\n", zi->lame_timer - now);
2849 }
2850 }
2851
2852 void
2853 dns_adb_dumpfind(dns_adbfind_t *find, FILE *f) {
2854 char tmp[512];
2855 const char *tmpp;
2856 dns_adbaddrinfo_t *ai;
2857 isc_sockaddr_t *sa;
2858
2859 /*
2860 * Not used currently, in the API Just In Case we
2861 * want to dump out the name and/or entries too.
2862 */
2863
2864 LOCK(&find->lock);
2865
2866 fprintf(f, ";Find %p\n", find);
2867 fprintf(f, ";\tqpending %08x partial %08x options %08x flags %08x\n",
2868 find->query_pending, find->partial_result,
2869 find->options, find->flags);
2870 fprintf(f, ";\tname_bucket %d, name %p, event sender %p\n",
2871 find->name_bucket, find->adbname, find->event.ev_sender);
2872
2873 ai = ISC_LIST_HEAD(find->list);
2874 if (ai != NULL)
2875 fprintf(f, "\tAddresses:\n");
2876 while (ai != NULL) {
2877 sa = &ai->sockaddr;
2878 switch (sa->type.sa.sa_family) {
2879 case AF_INET:
2880 tmpp = inet_ntop(AF_INET, &sa->type.sin.sin_addr,
2881 tmp, sizeof(tmp));
2882 break;
2883 case AF_INET6:
2884 tmpp = inet_ntop(AF_INET6, &sa->type.sin6.sin6_addr,
2885 tmp, sizeof(tmp));
2886 break;
2887 default:
2888 tmpp = "UnkFamily";
2889 }
2890
2891 if (tmpp == NULL)
2892 tmpp = "BadAddress";
2893
2894 fprintf(f, "\t\tentry %p, flags %08x"
2895 " srtt %u addr %s\n",
2896 ai->entry, ai->flags, ai->srtt, tmpp);
2897
2898 ai = ISC_LIST_NEXT(ai, publink);
2899 }
2900
2901 UNLOCK(&find->lock);
2902 }
2903
2904 static void
2905 print_dns_name(FILE *f, dns_name_t *name) {
2906 char buf[DNS_NAME_FORMATSIZE];
2907
2908 INSIST(f != NULL);
2909
2910 dns_name_format(name, buf, sizeof(buf));
2911 fprintf(f, "%s", buf);
2912 }
2913
2914 static void
2915 print_namehook_list(FILE *f, const char *legend, dns_adbnamehooklist_t *list,
2916 isc_boolean_t debug, isc_stdtime_t now)
2917 {
2918 dns_adbnamehook_t *nh;
2919
2920 for (nh = ISC_LIST_HEAD(*list);
2921 nh != NULL;
2922 nh = ISC_LIST_NEXT(nh, plink))
2923 {
2924 if (debug)
2925 fprintf(f, ";\tHook(%s) %p\n", legend, nh);
2926 dump_entry(f, nh->entry, debug, now);
2927 }
2928 }
2929
2930 static inline void
2931 print_fetch(FILE *f, dns_adbfetch_t *ft, const char *type) {
2932 fprintf(f, "\t\tFetch(%s): %p -> { nh %p, entry %p, fetch %p }\n",
2933 type, ft, ft->namehook, ft->entry, ft->fetch);
2934 }
2935
2936 static void
2937 print_fetch_list(FILE *f, dns_adbname_t *n) {
2938 if (NAME_FETCH_A(n))
2939 print_fetch(f, n->fetch_a, "A");
2940 if (NAME_FETCH_AAAA(n))
2941 print_fetch(f, n->fetch_aaaa, "AAAA");
2942 }
2943
2944 static void
2945 print_find_list(FILE *f, dns_adbname_t *name) {
2946 dns_adbfind_t *find;
2947
2948 find = ISC_LIST_HEAD(name->finds);
2949 while (find != NULL) {
2950 dns_adb_dumpfind(find, f);
2951 find = ISC_LIST_NEXT(find, plink);
2952 }
2953 }
2954
2955 static isc_result_t
2956 dbfind_name(dns_adbname_t *adbname, isc_stdtime_t now, dns_rdatatype_t rdtype)
2957 {
2958 isc_result_t result;
2959 dns_rdataset_t rdataset;
2960 dns_adb_t *adb;
2961 dns_fixedname_t foundname;
2962 dns_name_t *fname;
2963
2964 INSIST(DNS_ADBNAME_VALID(adbname));
2965 adb = adbname->adb;
2966 INSIST(DNS_ADB_VALID(adb));
2967 INSIST(rdtype == dns_rdatatype_a || rdtype == dns_rdatatype_aaaa);
2968
2969 dns_fixedname_init(&foundname);
2970 fname = dns_fixedname_name(&foundname);
2971 dns_rdataset_init(&rdataset);
2972
2973 if (rdtype == dns_rdatatype_a)
2974 adbname->fetch_err = FIND_ERR_UNEXPECTED;
2975 else
2976 adbname->fetch6_err = FIND_ERR_UNEXPECTED;
2977
2978 result = dns_view_find(adb->view, &adbname->name, rdtype, now,
2979 NAME_GLUEOK(adbname),
2980 ISC_TF(NAME_HINTOK(adbname)),
2981 NULL, NULL, fname, &rdataset, NULL);
2982
2983 /* XXXVIX this switch statement is too sparse to gen a jump table. */
2984 switch (result) {
2985 case DNS_R_GLUE:
2986 case DNS_R_HINT:
2987 case ISC_R_SUCCESS:
2988 /*
2989 * Found in the database. Even if we can't copy out
2990 * any information, return success, or else a fetch
2991 * will be made, which will only make things worse.
2992 */
2993 if (rdtype == dns_rdatatype_a)
2994 adbname->fetch_err = FIND_ERR_SUCCESS;
2995 else
2996 adbname->fetch6_err = FIND_ERR_SUCCESS;
2997 result = import_rdataset(adbname, &rdataset, now);
2998 break;
2999 case DNS_R_NXDOMAIN:
3000 case DNS_R_NXRRSET:
3001 /*
3002 * We're authoritative and the data doesn't exist.
3003 * Make up a negative cache entry so we don't ask again
3004 * for a while.
3005 *
3006 * XXXRTH What time should we use? I'm putting in 30 seconds
3007 * for now.
3008 */
3009 if (rdtype == dns_rdatatype_a) {
3010 adbname->expire_v4 = now + 30;
3011 DP(NCACHE_LEVEL,
3012 "adb name %p: Caching auth negative entry for A",
3013 adbname);
3014 if (result == DNS_R_NXDOMAIN)
3015 adbname->fetch_err = FIND_ERR_NXDOMAIN;
3016 else
3017 adbname->fetch_err = FIND_ERR_NXRRSET;
3018 } else {
3019 DP(NCACHE_LEVEL,
3020 "adb name %p: Caching auth negative entry for AAAA",
3021 adbname);
3022 adbname->expire_v6 = now + 30;
3023 if (result == DNS_R_NXDOMAIN)
3024 adbname->fetch6_err = FIND_ERR_NXDOMAIN;
3025 else
3026 adbname->fetch6_err = FIND_ERR_NXRRSET;
3027 }
3028 break;
3029 case DNS_R_NCACHENXDOMAIN:
3030 case DNS_R_NCACHENXRRSET:
3031 /*
3032 * We found a negative cache entry. Pull the TTL from it
3033 * so we won't ask again for a while.
3034 */
3035 rdataset.ttl = ttlclamp(rdataset.ttl);
3036 if (rdtype == dns_rdatatype_a) {
3037 adbname->expire_v4 = rdataset.ttl + now;
3038 if (result == DNS_R_NCACHENXDOMAIN)
3039 adbname->fetch_err = FIND_ERR_NXDOMAIN;
3040 else
3041 adbname->fetch_err = FIND_ERR_NXRRSET;
3042 DP(NCACHE_LEVEL,
3043 "adb name %p: Caching negative entry for A (ttl %u)",
3044 adbname, rdataset.ttl);
3045 } else {
3046 DP(NCACHE_LEVEL,
3047 "adb name %p: Caching negative entry for AAAA (ttl %u)",
3048 adbname, rdataset.ttl);
3049 adbname->expire_v6 = rdataset.ttl + now;
3050 if (result == DNS_R_NCACHENXDOMAIN)
3051 adbname->fetch6_err = FIND_ERR_NXDOMAIN;
3052 else
3053 adbname->fetch6_err = FIND_ERR_NXRRSET;
3054 }
3055 break;
3056 case DNS_R_CNAME:
3057 case DNS_R_DNAME:
3058 /*
3059 * Clear the hint and glue flags, so this will match
3060 * more often.
3061 */
3062 adbname->flags &= ~(DNS_ADBFIND_GLUEOK | DNS_ADBFIND_HINTOK);
3063
3064 rdataset.ttl = ttlclamp(rdataset.ttl);
3065 clean_target(adb, &adbname->target);
3066 adbname->expire_target = INT_MAX;
3067 result = set_target(adb, &adbname->name, fname, &rdataset,
3068 &adbname->target);
3069 if (result == ISC_R_SUCCESS) {
3070 result = DNS_R_ALIAS;
3071 DP(NCACHE_LEVEL,
3072 "adb name %p: caching alias target",
3073 adbname);
3074 adbname->expire_target = rdataset.ttl + now;
3075 }
3076 if (rdtype == dns_rdatatype_a)
3077 adbname->fetch_err = FIND_ERR_SUCCESS;
3078 else
3079 adbname->fetch6_err = FIND_ERR_SUCCESS;
3080 break;
3081 }
3082
3083 if (dns_rdataset_isassociated(&rdataset))
3084 dns_rdataset_disassociate(&rdataset);
3085
3086 return (result);
3087 }
3088
3089 static void
3090 fetch_callback(isc_task_t *task, isc_event_t *ev) {
3091 dns_fetchevent_t *dev;
3092 dns_adbname_t *name;
3093 dns_adb_t *adb;
3094 dns_adbfetch_t *fetch;
3095 int bucket;
3096 isc_eventtype_t ev_status;
3097 isc_stdtime_t now;
3098 isc_result_t result;
3099 unsigned int address_type;
3100 isc_boolean_t want_check_exit = ISC_FALSE;
3101
3102 UNUSED(task);
3103
3104 INSIST(ev->ev_type == DNS_EVENT_FETCHDONE);
3105 dev = (dns_fetchevent_t *)ev;
3106 name = ev->ev_arg;
3107 INSIST(DNS_ADBNAME_VALID(name));
3108 adb = name->adb;
3109 INSIST(DNS_ADB_VALID(adb));
3110
3111 bucket = name->lock_bucket;
3112 LOCK(&adb->namelocks[bucket]);
3113
3114 INSIST(NAME_FETCH_A(name) || NAME_FETCH_AAAA(name));
3115 address_type = 0;
3116 if (NAME_FETCH_A(name) && (name->fetch_a->fetch == dev->fetch)) {
3117 address_type = DNS_ADBFIND_INET;
3118 fetch = name->fetch_a;
3119 name->fetch_a = NULL;
3120 } else if (NAME_FETCH_AAAA(name)
3121 && (name->fetch_aaaa->fetch == dev->fetch)) {
3122 address_type = DNS_ADBFIND_INET6;
3123 fetch = name->fetch_aaaa;
3124 name->fetch_aaaa = NULL;
3125 }
3126 INSIST(address_type != 0);
3127
3128 dns_resolver_destroyfetch(&fetch->fetch);
3129 dev->fetch = NULL;
3130
3131 ev_status = DNS_EVENT_ADBNOMOREADDRESSES;
3132
3133 /*
3134 * Cleanup things we don't care about.
3135 */
3136 if (dev->node != NULL)
3137 dns_db_detachnode(dev->db, &dev->node);
3138 if (dev->db != NULL)
3139 dns_db_detach(&dev->db);
3140
3141 /*
3142 * If this name is marked as dead, clean up, throwing away
3143 * potentially good data.
3144 */
3145 if (NAME_DEAD(name)) {
3146 free_adbfetch(adb, &fetch);
3147 isc_event_free(&ev);
3148
3149 want_check_exit = kill_name(&name, DNS_EVENT_ADBCANCELED);
3150
3151 UNLOCK(&adb->namelocks[bucket]);
3152
3153 if (want_check_exit) {
3154 LOCK(&adb->lock);
3155 check_exit(adb);
3156 UNLOCK(&adb->lock);
3157 }
3158
3159 return;
3160 }
3161
3162 isc_stdtime_get(&now);
3163
3164 /*
3165 * If we got a negative cache response, remember it.
3166 */
3167 if (NCACHE_RESULT(dev->result)) {
3168 dev->rdataset->ttl = ttlclamp(dev->rdataset->ttl);
3169 if (address_type == DNS_ADBFIND_INET) {
3170 DP(NCACHE_LEVEL, "adb fetch name %p: "
3171 "caching negative entry for A (ttl %u)",
3172 name, dev->rdataset->ttl);
3173 name->expire_v4 = ISC_MIN(name->expire_v4,
3174 dev->rdataset->ttl + now);
3175 if (dev->result == DNS_R_NCACHENXDOMAIN)
3176 name->fetch_err = FIND_ERR_NXDOMAIN;
3177 else
3178 name->fetch_err = FIND_ERR_NXRRSET;
3179 } else {
3180 DP(NCACHE_LEVEL, "adb fetch name %p: "
3181 "caching negative entry for AAAA (ttl %u)",
3182 name, dev->rdataset->ttl);
3183 name->expire_v6 = ISC_MIN(name->expire_v6,
3184 dev->rdataset->ttl + now);
3185 if (dev->result == DNS_R_NCACHENXDOMAIN)
3186 name->fetch6_err = FIND_ERR_NXDOMAIN;
3187 else
3188 name->fetch6_err = FIND_ERR_NXRRSET;
3189 }
3190 goto out;
3191 }
3192
3193 /*
3194 * Handle CNAME/DNAME.
3195 */
3196 if (dev->result == DNS_R_CNAME || dev->result == DNS_R_DNAME) {
3197 dev->rdataset->ttl = ttlclamp(dev->rdataset->ttl);
3198 clean_target(adb, &name->target);
3199 name->expire_target = INT_MAX;
3200 result = set_target(adb, &name->name,
3201 dns_fixedname_name(&dev->foundname),
3202 dev->rdataset,
3203 &name->target);
3204 if (result == ISC_R_SUCCESS) {
3205 DP(NCACHE_LEVEL,
3206 "adb fetch name %p: caching alias target",
3207 name);
3208 name->expire_target = dev->rdataset->ttl + now;
3209 }
3210 goto check_result;
3211 }
3212
3213 /*
3214 * Did we get back junk? If so, and there are no more fetches
3215 * sitting out there, tell all the finds about it.
3216 */
3217 if (dev->result != ISC_R_SUCCESS) {
3218 char buf[DNS_NAME_FORMATSIZE];
3219
3220 dns_name_format(&name->name, buf, sizeof(buf));
3221 DP(DEF_LEVEL, "adb: fetch of '%s' %s failed: %s",
3222 buf, address_type == DNS_ADBFIND_INET ? "A" : "AAAA",
3223 dns_result_totext(dev->result));
3224 /* XXXMLG Don't pound on bad servers. */
3225 if (address_type == DNS_ADBFIND_INET) {
3226 name->expire_v4 = ISC_MIN(name->expire_v4, now + 300);
3227 name->fetch_err = FIND_ERR_FAILURE;
3228 } else {
3229 name->expire_v6 = ISC_MIN(name->expire_v6, now + 300);
3230 name->fetch6_err = FIND_ERR_FAILURE;
3231 }
3232 goto out;
3233 }
3234
3235 /*
3236 * We got something potentially useful.
3237 */
3238 result = import_rdataset(name, &fetch->rdataset, now);
3239
3240 check_result:
3241 if (result == ISC_R_SUCCESS) {
3242 ev_status = DNS_EVENT_ADBMOREADDRESSES;
3243 if (address_type == DNS_ADBFIND_INET)
3244 name->fetch_err = FIND_ERR_SUCCESS;
3245 else
3246 name->fetch6_err = FIND_ERR_SUCCESS;
3247 }
3248
3249 out:
3250 free_adbfetch(adb, &fetch);
3251 isc_event_free(&ev);
3252
3253 clean_finds_at_name(name, ev_status, address_type);
3254
3255 UNLOCK(&adb->namelocks[bucket]);
3256 }
3257
3258 static isc_result_t
3259 fetch_name(dns_adbname_t *adbname,
3260 isc_boolean_t start_at_zone,
3261 dns_rdatatype_t type)
3262 {
3263 isc_result_t result;
3264 dns_adbfetch_t *fetch = NULL;
3265 dns_adb_t *adb;
3266 dns_fixedname_t fixed;
3267 dns_name_t *name;
3268 dns_rdataset_t rdataset;
3269 dns_rdataset_t *nameservers;
3270 unsigned int options;
3271
3272 INSIST(DNS_ADBNAME_VALID(adbname));
3273 adb = adbname->adb;
3274 INSIST(DNS_ADB_VALID(adb));
3275
3276 INSIST((type == dns_rdatatype_a && !NAME_FETCH_V4(adbname)) ||
3277 (type == dns_rdatatype_aaaa && !NAME_FETCH_V6(adbname)));
3278
3279 adbname->fetch_err = FIND_ERR_NOTFOUND;
3280
3281 name = NULL;
3282 nameservers = NULL;
3283 dns_rdataset_init(&rdataset);
3284
3285 options = DNS_FETCHOPT_NOVALIDATE;
3286 if (start_at_zone) {
3287 DP(ENTER_LEVEL,
3288 "fetch_name: starting at zone for name %p",
3289 adbname);
3290 dns_fixedname_init(&fixed);
3291 name = dns_fixedname_name(&fixed);
3292 result = dns_view_findzonecut2(adb->view, &adbname->name, name,
3293 0, 0, ISC_TRUE, ISC_FALSE,
3294 &rdataset, NULL);
3295 if (result != ISC_R_SUCCESS && result != DNS_R_HINT)
3296 goto cleanup;
3297 nameservers = &rdataset;
3298 options |= DNS_FETCHOPT_UNSHARED;
3299 }
3300
3301 fetch = new_adbfetch(adb);
3302 if (fetch == NULL) {
3303 result = ISC_R_NOMEMORY;
3304 goto cleanup;
3305 }
3306
3307 result = dns_resolver_createfetch(adb->view->resolver, &adbname->name,
3308 type, name, nameservers, NULL,
3309 options, adb->task, fetch_callback,
3310 adbname, &fetch->rdataset, NULL,
3311 &fetch->fetch);
3312 if (result != ISC_R_SUCCESS)
3313 goto cleanup;
3314
3315 if (type == dns_rdatatype_a)
3316 adbname->fetch_a = fetch;
3317 else
3318 adbname->fetch_aaaa = fetch;
3319 fetch = NULL; /* Keep us from cleaning this up below. */
3320
3321 cleanup:
3322 if (fetch != NULL)
3323 free_adbfetch(adb, &fetch);
3324 if (dns_rdataset_isassociated(&rdataset))
3325 dns_rdataset_disassociate(&rdataset);
3326
3327 return (result);
3328 }
3329
3330 /*
3331 * XXXMLG Needs to take a find argument and an address info, no zone or adb,
3332 * since these can be extracted from the find itself.
3333 */
3334 isc_result_t
3335 dns_adb_marklame(dns_adb_t *adb, dns_adbaddrinfo_t *addr, dns_name_t *zone,
3336 isc_stdtime_t expire_time)
3337 {
3338 dns_adbzoneinfo_t *zi;
3339 int bucket;
3340 isc_result_t result = ISC_R_SUCCESS;
3341
3342 REQUIRE(DNS_ADB_VALID(adb));
3343 REQUIRE(DNS_ADBADDRINFO_VALID(addr));
3344 REQUIRE(zone != NULL);
3345
3346 bucket = addr->entry->lock_bucket;
3347 LOCK(&adb->entrylocks[bucket]);
3348 zi = ISC_LIST_HEAD(addr->entry->zoneinfo);
3349 while (zi != NULL && !dns_name_equal(zone, &zi->zone))
3350 zi = ISC_LIST_NEXT(zi, plink);
3351 if (zi != NULL) {
3352 if (expire_time > zi->lame_timer)
3353 zi->lame_timer = expire_time;
3354 goto unlock;
3355 }
3356 zi = new_adbzoneinfo(adb, zone);
3357 if (zi == NULL) {
3358 result = ISC_R_NOMEMORY;
3359 goto unlock;
3360 }
3361
3362 zi->lame_timer = expire_time;
3363
3364 ISC_LIST_PREPEND(addr->entry->zoneinfo, zi, plink);
3365 unlock:
3366 UNLOCK(&adb->entrylocks[bucket]);
3367
3368 return (result);
3369 }
3370
3371 void
3372 dns_adb_adjustsrtt(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
3373 unsigned int rtt, unsigned int factor)
3374 {
3375 int bucket;
3376 unsigned int new_srtt;
3377 isc_stdtime_t now;
3378
3379 REQUIRE(DNS_ADB_VALID(adb));
3380 REQUIRE(DNS_ADBADDRINFO_VALID(addr));
3381 REQUIRE(factor <= 10);
3382
3383 bucket = addr->entry->lock_bucket;
3384 LOCK(&adb->entrylocks[bucket]);
3385
3386 if (factor == DNS_ADB_RTTADJAGE)
3387 new_srtt = addr->entry->srtt * 98 / 100;
3388 else
3389 new_srtt = (addr->entry->srtt / 10 * factor)
3390 + (rtt / 10 * (10 - factor));
3391
3392 addr->entry->srtt = new_srtt;
3393 addr->srtt = new_srtt;
3394
3395 isc_stdtime_get(&now);
3396 addr->entry->expires = now + ADB_ENTRY_WINDOW;
3397
3398 UNLOCK(&adb->entrylocks[bucket]);
3399 }
3400
3401 void
3402 dns_adb_changeflags(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
3403 unsigned int bits, unsigned int mask)
3404 {
3405 int bucket;
3406
3407 REQUIRE(DNS_ADB_VALID(adb));
3408 REQUIRE(DNS_ADBADDRINFO_VALID(addr));
3409
3410 bucket = addr->entry->lock_bucket;
3411 LOCK(&adb->entrylocks[bucket]);
3412
3413 addr->entry->flags = (addr->entry->flags & ~mask) | (bits & mask);
3414 /*
3415 * Note that we do not update the other bits in addr->flags with
3416 * the most recent values from addr->entry->flags.
3417 */
3418 addr->flags = (addr->flags & ~mask) | (bits & mask);
3419
3420 UNLOCK(&adb->entrylocks[bucket]);
3421 }
3422
3423 isc_result_t
3424 dns_adb_findaddrinfo(dns_adb_t *adb, isc_sockaddr_t *sa,
3425 dns_adbaddrinfo_t **addrp, isc_stdtime_t now)
3426 {
3427 int bucket;
3428 dns_adbentry_t *entry;
3429 dns_adbaddrinfo_t *addr;
3430 isc_result_t result;
3431 in_port_t port;
3432
3433 REQUIRE(DNS_ADB_VALID(adb));
3434 REQUIRE(addrp != NULL && *addrp == NULL);
3435
3436 UNUSED(now);
3437
3438 result = ISC_R_SUCCESS;
3439 bucket = DNS_ADB_INVALIDBUCKET;
3440 entry = find_entry_and_lock(adb, sa, &bucket);
3441 if (adb->entry_sd[bucket]) {
3442 result = ISC_R_SHUTTINGDOWN;
3443 goto unlock;
3444 }
3445 if (entry == NULL) {
3446 /*
3447 * We don't know anything about this address.
3448 */
3449 entry = new_adbentry(adb);
3450 if (entry == NULL) {
3451 result = ISC_R_NOMEMORY;
3452 goto unlock;
3453 }
3454 entry->sockaddr = *sa;
3455 link_entry(adb, bucket, entry);
3456 DP(ENTER_LEVEL, "findaddrinfo: new entry %p", entry);
3457 } else
3458 DP(ENTER_LEVEL, "findaddrinfo: found entry %p", entry);
3459
3460 port = isc_sockaddr_getport(sa);
3461 addr = new_adbaddrinfo(adb, entry, port);
3462 if (addr != NULL) {
3463 inc_entry_refcnt(adb, entry, ISC_FALSE);
3464 *addrp = addr;
3465 }
3466
3467 unlock:
3468 UNLOCK(&adb->entrylocks[bucket]);
3469
3470 return (result);
3471 }
3472
3473 void
3474 dns_adb_freeaddrinfo(dns_adb_t *adb, dns_adbaddrinfo_t **addrp) {
3475 dns_adbaddrinfo_t *addr;
3476 dns_adbentry_t *entry;
3477 int bucket;
3478 isc_stdtime_t now;
3479 isc_boolean_t want_check_exit = ISC_FALSE;
3480
3481 REQUIRE(DNS_ADB_VALID(adb));
3482 REQUIRE(addrp != NULL);
3483 addr = *addrp;
3484 REQUIRE(DNS_ADBADDRINFO_VALID(addr));
3485 entry = addr->entry;
3486 REQUIRE(DNS_ADBENTRY_VALID(entry));
3487
3488 isc_stdtime_get(&now);
3489
3490 *addrp = NULL;
3491
3492 bucket = addr->entry->lock_bucket;
3493 LOCK(&adb->entrylocks[bucket]);
3494
3495 entry->expires = now + ADB_ENTRY_WINDOW;
3496
3497 want_check_exit = dec_entry_refcnt(adb, entry, ISC_FALSE);
3498
3499 UNLOCK(&adb->entrylocks[bucket]);
3500
3501 addr->entry = NULL;
3502 free_adbaddrinfo(adb, &addr);
3503
3504 if (want_check_exit) {
3505 LOCK(&adb->lock);
3506 check_exit(adb);
3507 UNLOCK(&adb->lock);
3508 }
3509 }
3510
3511 void
3512 dns_adb_flush(dns_adb_t *adb) {
3513 unsigned int i;
3514
3515 INSIST(DNS_ADB_VALID(adb));
3516
3517 LOCK(&adb->lock);
3518
3519 /*
3520 * Call our cleanup routines.
3521 */
3522 for (i = 0; i < NBUCKETS; i++)
3523 RUNTIME_CHECK(cleanup_names(adb, i, INT_MAX) == ISC_FALSE);
3524 for (i = 0; i < NBUCKETS; i++)
3525 RUNTIME_CHECK(cleanup_entries(adb, i, INT_MAX) == ISC_FALSE);
3526
3527 #ifdef DUMP_ADB_AFTER_CLEANING
3528 dump_adb(adb, stdout, ISC_TRUE, INT_MAX);
3529 #endif
3530
3531 UNLOCK(&adb->lock);
3532 }
3533
3534 void
3535 dns_adb_flushname(dns_adb_t *adb, dns_name_t *name) {
3536 dns_adbname_t *adbname;
3537 dns_adbname_t *nextname;
3538 int bucket;
3539
3540 INSIST(DNS_ADB_VALID(adb));
3541
3542 LOCK(&adb->lock);
3543 bucket = dns_name_hash(name, ISC_FALSE) % NBUCKETS;
3544 LOCK(&adb->namelocks[bucket]);
3545 adbname = ISC_LIST_HEAD(adb->names[bucket]);
3546 while (adbname != NULL) {
3547 nextname = ISC_LIST_NEXT(adbname, plink);
3548 if (!NAME_DEAD(adbname) &&
3549 dns_name_equal(name, &adbname->name)) {
3550 RUNTIME_CHECK(kill_name(&adbname,
3551 DNS_EVENT_ADBCANCELED) ==
3552 ISC_FALSE);
3553 }
3554 adbname = nextname;
3555 }
3556 UNLOCK(&adb->namelocks[bucket]);
3557 UNLOCK(&adb->lock);
3558 }
3559
3560 static void
3561 water(void *arg, int mark) {
3562 dns_adb_t *adb = arg;
3563 isc_boolean_t overmem = ISC_TF(mark == ISC_MEM_HIWATER);
3564 isc_interval_t interval;
3565
3566 REQUIRE(DNS_ADB_VALID(adb));
3567
3568 DP(ISC_LOG_DEBUG(1),
3569 "adb reached %s water mark", overmem ? "high" : "low");
3570
3571 adb->overmem = overmem;
3572 if (overmem) {
3573 isc_interval_set(&interval, 0, 1);
3574 (void)isc_timer_reset(adb->timer, isc_timertype_once, NULL,
3575 &interval, ISC_TRUE);
3576 }
3577 }
3578
3579 void
3580 dns_adb_setadbsize(dns_adb_t *adb, isc_uint32_t size) {
3581 isc_uint32_t hiwater;
3582 isc_uint32_t lowater;
3583
3584 INSIST(DNS_ADB_VALID(adb));
3585
3586 if (size != 0 && size < DNS_ADB_MINADBSIZE)
3587 size = DNS_ADB_MINADBSIZE;
3588
3589 hiwater = size - (size >> 3); /* Approximately 7/8ths. */
3590 lowater = size - (size >> 2); /* Approximately 3/4ths. */
3591
3592 if (size == 0 || hiwater == 0 || lowater == 0)
3593 isc_mem_setwater(adb->mctx, water, adb, 0, 0);
3594 else
3595 isc_mem_setwater(adb->mctx, water, adb, hiwater, lowater);
3596 }
DragonFly BSD