Mercurial > hg > nginx-vendor-0-7
comparison src/core/ngx_resolver.c @ 350:5a1bb0129dff NGINX_0_6_19
nginx 0.6.19
*) Bugfix: the 0.6.18 version could not be built.
author | Igor Sysoev <http://sysoev.ru> |
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date | Tue, 27 Nov 2007 00:00:00 +0300 |
parents | |
children | 583decdb82a4 |
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349:c524d806a2eb | 350:5a1bb0129dff |
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1 | |
2 /* | |
3 * Copyright (C) Igor Sysoev | |
4 */ | |
5 | |
6 | |
7 #include <ngx_config.h> | |
8 #include <ngx_core.h> | |
9 #include <ngx_event.h> | |
10 | |
11 | |
12 #define NGX_RESOLVER_UDP_SIZE 4096 | |
13 | |
14 | |
15 typedef struct { | |
16 u_char ident_hi; | |
17 u_char ident_lo; | |
18 u_char flags_hi; | |
19 u_char flags_lo; | |
20 u_char nqs_hi; | |
21 u_char nqs_lo; | |
22 u_char nan_hi; | |
23 u_char nan_lo; | |
24 u_char nns_hi; | |
25 u_char nns_lo; | |
26 u_char nar_hi; | |
27 u_char nar_lo; | |
28 } ngx_resolver_query_t; | |
29 | |
30 | |
31 typedef struct { | |
32 u_char type_hi; | |
33 u_char type_lo; | |
34 u_char class_hi; | |
35 u_char class_lo; | |
36 } ngx_resolver_qs_t; | |
37 | |
38 | |
39 typedef struct { | |
40 u_char type_hi; | |
41 u_char type_lo; | |
42 u_char class_hi; | |
43 u_char class_lo; | |
44 u_char ttl[4]; | |
45 u_char len_hi; | |
46 u_char len_lo; | |
47 } ngx_resolver_an_t; | |
48 | |
49 | |
50 ngx_int_t ngx_udp_connect(ngx_udp_connection_t *uc); | |
51 | |
52 | |
53 static ngx_int_t ngx_resolve_name_locked(ngx_resolver_t *r, | |
54 ngx_resolver_ctx_t *ctx); | |
55 static void ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree, | |
56 ngx_queue_t *queue); | |
57 static ngx_int_t ngx_resolver_send_query(ngx_resolver_t *r, | |
58 ngx_resolver_node_t *rn); | |
59 static ngx_int_t ngx_resolver_create_name_query(ngx_resolver_node_t *rn, | |
60 ngx_resolver_ctx_t *ctx); | |
61 static ngx_int_t ngx_resolver_create_addr_query(ngx_resolver_node_t *rn, | |
62 ngx_resolver_ctx_t *ctx); | |
63 static void ngx_resolver_resend_handler(ngx_event_t *ev); | |
64 static time_t ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree, | |
65 ngx_queue_t *queue); | |
66 static void ngx_resolver_read_response(ngx_event_t *rev); | |
67 static void ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf, | |
68 size_t n); | |
69 static void ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t n, | |
70 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t i); | |
71 static void ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n, | |
72 ngx_uint_t ident, ngx_uint_t code); | |
73 static ngx_resolver_node_t *ngx_resolver_lookup_name(ngx_resolver_t *r, | |
74 ngx_str_t *name, uint32_t hash); | |
75 static ngx_resolver_node_t *ngx_resolver_lookup_addr(ngx_resolver_t *r, | |
76 in_addr_t addr); | |
77 static void ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp, | |
78 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel); | |
79 static ngx_int_t ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name, | |
80 u_char *buf, u_char *src, u_char *last); | |
81 static void ngx_resolver_timeout_handler(ngx_event_t *ev); | |
82 static void ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn); | |
83 static void *ngx_resolver_alloc(ngx_resolver_t *r, size_t size); | |
84 static void ngx_resolver_free(ngx_resolver_t *r, void *p); | |
85 static void ngx_resolver_free_locked(ngx_resolver_t *r, void *p); | |
86 static void *ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size); | |
87 | |
88 | |
89 /* STUB: ngx_peer_addr_t * */ | |
90 | |
91 ngx_resolver_t * | |
92 ngx_resolver_create(ngx_peer_addr_t *addr, ngx_log_t *log) | |
93 { | |
94 ngx_resolver_t *r; | |
95 ngx_udp_connection_t *uc; | |
96 | |
97 r = ngx_calloc(sizeof(ngx_resolver_t), log); | |
98 if (r == NULL) { | |
99 return NULL; | |
100 } | |
101 | |
102 uc = ngx_calloc(sizeof(ngx_udp_connection_t), log); | |
103 if (uc == NULL) { | |
104 return NULL; | |
105 } | |
106 | |
107 r->event = ngx_calloc(sizeof(ngx_event_t), log); | |
108 if (r->event == NULL) { | |
109 return NULL; | |
110 } | |
111 | |
112 ngx_rbtree_sentinel_init(&r->name_sentinel); | |
113 | |
114 r->name_rbtree.root = &r->name_sentinel; | |
115 r->name_rbtree.sentinel = &r->name_sentinel; | |
116 r->name_rbtree.insert = ngx_resolver_rbtree_insert_value; | |
117 | |
118 ngx_rbtree_sentinel_init(&r->addr_sentinel); | |
119 | |
120 r->addr_rbtree.root = &r->addr_sentinel; | |
121 r->addr_rbtree.sentinel = &r->addr_sentinel; | |
122 r->addr_rbtree.insert = ngx_rbtree_insert_value; | |
123 | |
124 r->name_resend_queue.prev = &r->name_resend_queue; | |
125 r->name_resend_queue.next = &r->name_resend_queue; | |
126 | |
127 r->addr_resend_queue.prev = &r->addr_resend_queue; | |
128 r->addr_resend_queue.next = &r->addr_resend_queue; | |
129 | |
130 r->name_expire_queue.prev = &r->name_expire_queue; | |
131 r->name_expire_queue.next = &r->name_expire_queue; | |
132 | |
133 r->addr_expire_queue.prev = &r->addr_expire_queue; | |
134 r->addr_expire_queue.next = &r->addr_expire_queue; | |
135 | |
136 r->event->handler = ngx_resolver_resend_handler; | |
137 r->event->data = r; | |
138 r->event->log = log; | |
139 r->ident = -1; | |
140 | |
141 r->udp_connection = uc; | |
142 | |
143 r->resend_timeout = 5; | |
144 r->expire = 30; | |
145 r->valid = 300; | |
146 | |
147 r->log = log; | |
148 r->log_level = NGX_LOG_ALERT; | |
149 | |
150 uc->sockaddr = addr->sockaddr; | |
151 uc->socklen = addr->socklen; | |
152 uc->server = addr->name; | |
153 uc->log = log; | |
154 | |
155 return r; | |
156 } | |
157 | |
158 | |
159 ngx_resolver_ctx_t * | |
160 ngx_resolve_start(ngx_resolver_t *r, ngx_resolver_ctx_t *temp) | |
161 { | |
162 in_addr_t addr; | |
163 ngx_resolver_ctx_t *ctx; | |
164 | |
165 if (temp) { | |
166 addr = ngx_inet_addr(temp->name.data, temp->name.len); | |
167 | |
168 if (addr != INADDR_NONE) { | |
169 temp->resolver = r; | |
170 temp->state = NGX_OK; | |
171 temp->naddrs = 1; | |
172 temp->addrs = &temp->addr; | |
173 temp->addr = addr; | |
174 temp->quick = 1; | |
175 | |
176 return temp; | |
177 } | |
178 } | |
179 | |
180 ctx = ngx_resolver_calloc(r, sizeof(ngx_resolver_ctx_t)); | |
181 | |
182 if (ctx) { | |
183 ctx->resolver = r; | |
184 } | |
185 | |
186 return ctx; | |
187 } | |
188 | |
189 | |
190 ngx_int_t | |
191 ngx_resolve_name(ngx_resolver_ctx_t *ctx) | |
192 { | |
193 ngx_int_t rc; | |
194 ngx_resolver_t *r; | |
195 | |
196 r = ctx->resolver; | |
197 | |
198 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, | |
199 "resolve: \"%V\"", &ctx->name); | |
200 | |
201 if (ctx->quick) { | |
202 ctx->handler(ctx); | |
203 return NGX_OK; | |
204 } | |
205 | |
206 /* lock name mutex */ | |
207 | |
208 rc = ngx_resolve_name_locked(r, ctx); | |
209 | |
210 if (rc == NGX_OK) { | |
211 return NGX_OK; | |
212 } | |
213 | |
214 /* unlock name mutex */ | |
215 | |
216 if (rc == NGX_AGAIN) { | |
217 return NGX_OK; | |
218 } | |
219 | |
220 /* lock alloc mutex */ | |
221 | |
222 if (ctx->event) { | |
223 ngx_resolver_free_locked(r, ctx->event); | |
224 } | |
225 | |
226 ngx_resolver_free_locked(r, ctx); | |
227 | |
228 /* unlock alloc mutex */ | |
229 | |
230 return NGX_ERROR; | |
231 } | |
232 | |
233 | |
234 void | |
235 ngx_resolve_name_done(ngx_resolver_ctx_t *ctx) | |
236 { | |
237 uint32_t hash; | |
238 ngx_resolver_t *r; | |
239 ngx_resolver_ctx_t *w, **p; | |
240 ngx_resolver_node_t *rn; | |
241 | |
242 r = ctx->resolver; | |
243 | |
244 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, | |
245 "resolve name done: %i", ctx->state); | |
246 | |
247 if (ctx->quick) { | |
248 return; | |
249 } | |
250 | |
251 if (ctx->event && ctx->event->timer_set) { | |
252 ngx_del_timer(ctx->event); | |
253 } | |
254 | |
255 /* lock name mutex */ | |
256 | |
257 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) { | |
258 | |
259 hash = ngx_crc32_short(ctx->name.data, ctx->name.len); | |
260 | |
261 rn = ngx_resolver_lookup_name(r, &ctx->name, hash); | |
262 | |
263 if (rn) { | |
264 p = &rn->waiting; | |
265 w = rn->waiting; | |
266 | |
267 while (w) { | |
268 if (w == ctx) { | |
269 *p = w->next; | |
270 | |
271 goto done; | |
272 } | |
273 | |
274 p = &w->next; | |
275 w = w->next; | |
276 } | |
277 } | |
278 | |
279 ngx_log_error(NGX_LOG_ALERT, r->log, 0, | |
280 "could not cancel %V resolving", &ctx->name); | |
281 } | |
282 | |
283 done: | |
284 | |
285 ngx_resolver_expire(r, &r->name_rbtree, &r->name_expire_queue); | |
286 | |
287 /* unlock name mutex */ | |
288 | |
289 ngx_resolver_free(r, ctx); | |
290 } | |
291 | |
292 | |
293 /* NGX_RESOLVE_A only */ | |
294 | |
295 static ngx_int_t | |
296 ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx) | |
297 { | |
298 uint32_t hash; | |
299 in_addr_t addr, *addrs; | |
300 ngx_uint_t naddrs; | |
301 ngx_resolver_ctx_t *next; | |
302 ngx_resolver_node_t *rn; | |
303 | |
304 hash = ngx_crc32_short(ctx->name.data, ctx->name.len); | |
305 | |
306 rn = ngx_resolver_lookup_name(r, &ctx->name, hash); | |
307 | |
308 if (rn) { | |
309 | |
310 if (rn->valid >= ngx_time()) { | |
311 | |
312 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached"); | |
313 | |
314 ngx_queue_remove(&rn->queue); | |
315 | |
316 rn->expire = ngx_time() + r->expire; | |
317 | |
318 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue); | |
319 | |
320 naddrs = rn->naddrs; | |
321 | |
322 if (naddrs) { | |
323 | |
324 /* NGX_RESOLVE_A answer */ | |
325 | |
326 if (naddrs != 1) { | |
327 addr = 0; | |
328 addrs = ngx_resolver_dup(r, rn->u.addrs, | |
329 naddrs * sizeof(in_addr_t)); | |
330 if (addrs == NULL) { | |
331 return NGX_ERROR; | |
332 } | |
333 | |
334 } else { | |
335 addr = rn->u.addr; | |
336 addrs = NULL; | |
337 } | |
338 | |
339 ctx->next = rn->waiting; | |
340 rn->waiting = NULL; | |
341 | |
342 /* unlock name mutex */ | |
343 | |
344 do { | |
345 ctx->state = NGX_OK; | |
346 ctx->naddrs = naddrs; | |
347 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs; | |
348 ctx->addr = addr; | |
349 next = ctx->next; | |
350 | |
351 ctx->handler(ctx); | |
352 | |
353 ctx = next; | |
354 } while (ctx); | |
355 | |
356 if (addrs) { | |
357 ngx_resolver_free(r, addrs); | |
358 } | |
359 | |
360 return NGX_OK; | |
361 } | |
362 | |
363 /* NGX_RESOLVE_CNAME */ | |
364 | |
365 ctx->name.len = rn->cnlen; | |
366 ctx->name.data = rn->u.cname; | |
367 | |
368 return ngx_resolve_name_locked(r, ctx); | |
369 } | |
370 | |
371 if (rn->waiting) { | |
372 | |
373 ctx->next = rn->waiting; | |
374 rn->waiting = ctx; | |
375 | |
376 return NGX_AGAIN; | |
377 } | |
378 | |
379 ngx_queue_remove(&rn->queue); | |
380 | |
381 /* lock alloc mutex */ | |
382 | |
383 ngx_resolver_free_locked(r, rn->query); | |
384 | |
385 if (rn->cnlen) { | |
386 ngx_resolver_free_locked(r, rn->u.cname); | |
387 } | |
388 | |
389 if (rn->naddrs > 1) { | |
390 ngx_resolver_free_locked(r, rn->u.addrs); | |
391 } | |
392 | |
393 /* unlock alloc mutex */ | |
394 | |
395 } else { | |
396 | |
397 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t)); | |
398 if (rn == NULL) { | |
399 return NGX_ERROR; | |
400 } | |
401 | |
402 rn->name = ngx_resolver_dup(r, ctx->name.data, ctx->name.len); | |
403 if (rn->name == NULL) { | |
404 ngx_resolver_free(r, rn); | |
405 return NGX_ERROR; | |
406 } | |
407 | |
408 rn->node.key = hash; | |
409 rn->nlen = (u_short) ctx->name.len; | |
410 | |
411 ngx_rbtree_insert(&r->name_rbtree, &rn->node); | |
412 } | |
413 | |
414 if (ngx_resolver_create_name_query(rn, ctx) != NGX_OK) { | |
415 goto failed; | |
416 } | |
417 | |
418 if (ngx_resolver_send_query(r, rn) != NGX_OK) { | |
419 goto failed; | |
420 } | |
421 | |
422 if (ctx->event == NULL) { | |
423 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t)); | |
424 if (ctx->event == NULL) { | |
425 goto failed; | |
426 } | |
427 | |
428 ctx->event->handler = ngx_resolver_timeout_handler; | |
429 ctx->event->data = ctx; | |
430 ctx->event->log = r->log; | |
431 ctx->ident = -1; | |
432 | |
433 ngx_add_timer(ctx->event, ctx->timeout); | |
434 } | |
435 | |
436 if (ngx_queue_empty(&r->name_resend_queue)) { | |
437 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000)); | |
438 } | |
439 | |
440 rn->expire = ngx_time() + r->resend_timeout; | |
441 | |
442 ngx_queue_insert_head(&r->name_resend_queue, &rn->queue); | |
443 | |
444 rn->cnlen = 0; | |
445 rn->naddrs = 0; | |
446 rn->valid = 0; | |
447 rn->waiting = ctx; | |
448 | |
449 ctx->state = NGX_AGAIN; | |
450 | |
451 return NGX_AGAIN; | |
452 | |
453 failed: | |
454 | |
455 ngx_rbtree_delete(&r->name_rbtree, &rn->node); | |
456 | |
457 ngx_resolver_free(r, rn->name); | |
458 | |
459 ngx_resolver_free(r, rn); | |
460 | |
461 return NGX_ERROR; | |
462 } | |
463 | |
464 | |
465 ngx_int_t | |
466 ngx_resolve_addr(ngx_resolver_ctx_t *ctx) | |
467 { | |
468 ngx_resolver_t *r; | |
469 ngx_resolver_node_t *rn; | |
470 | |
471 r = ctx->resolver; | |
472 | |
473 ctx->addr = ntohl(ctx->addr); | |
474 | |
475 /* lock addr mutex */ | |
476 | |
477 rn = ngx_resolver_lookup_addr(r, ctx->addr); | |
478 | |
479 if (rn) { | |
480 | |
481 if (rn->valid >= ngx_time()) { | |
482 | |
483 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached"); | |
484 | |
485 ngx_queue_remove(&rn->queue); | |
486 | |
487 rn->expire = ngx_time() + r->expire; | |
488 | |
489 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue); | |
490 | |
491 ctx->name.len = rn->nlen; | |
492 ctx->name.data = ngx_resolver_dup(r, rn->name, rn->nlen); | |
493 if (ctx->name.data == NULL) { | |
494 goto failed; | |
495 } | |
496 | |
497 /* unlock addr mutex */ | |
498 | |
499 ctx->state = NGX_OK; | |
500 | |
501 ctx->handler(ctx); | |
502 | |
503 ngx_resolver_free(r, ctx->name.data); | |
504 | |
505 return NGX_OK; | |
506 } | |
507 | |
508 if (rn->waiting) { | |
509 | |
510 ctx->next = rn->waiting; | |
511 rn->waiting = ctx; | |
512 | |
513 return NGX_AGAIN; | |
514 } | |
515 | |
516 ngx_queue_remove(&rn->queue); | |
517 | |
518 ngx_resolver_free(r, rn->query); | |
519 | |
520 } else { | |
521 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t)); | |
522 if (rn == NULL) { | |
523 goto failed; | |
524 } | |
525 | |
526 rn->node.key = ctx->addr; | |
527 | |
528 ngx_rbtree_insert(&r->addr_rbtree, &rn->node); | |
529 } | |
530 | |
531 if (ngx_resolver_create_addr_query(rn, ctx) != NGX_OK) { | |
532 goto failed; | |
533 } | |
534 | |
535 if (ngx_resolver_send_query(r, rn) != NGX_OK) { | |
536 goto failed; | |
537 } | |
538 | |
539 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t)); | |
540 if (ctx->event == NULL) { | |
541 goto failed; | |
542 } | |
543 | |
544 ctx->event->handler = ngx_resolver_timeout_handler; | |
545 ctx->event->data = ctx; | |
546 ctx->event->log = r->log; | |
547 ctx->ident = -1; | |
548 | |
549 ngx_add_timer(ctx->event, ctx->timeout); | |
550 | |
551 if (ngx_queue_empty(&r->addr_resend_queue)) { | |
552 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000)); | |
553 } | |
554 | |
555 rn->expire = ngx_time() + r->resend_timeout; | |
556 | |
557 ngx_queue_insert_head(&r->addr_resend_queue, &rn->queue); | |
558 | |
559 rn->cnlen = 0; | |
560 rn->naddrs = 0; | |
561 rn->name = NULL; | |
562 rn->nlen = 0; | |
563 rn->valid = 0; | |
564 rn->waiting = ctx; | |
565 | |
566 /* unlock addr mutex */ | |
567 | |
568 ctx->state = NGX_AGAIN; | |
569 | |
570 return NGX_OK; | |
571 | |
572 failed: | |
573 | |
574 if (rn) { | |
575 ngx_rbtree_delete(&r->addr_rbtree, &rn->node); | |
576 | |
577 ngx_resolver_free(r, rn); | |
578 } | |
579 | |
580 /* unlock addr mutex */ | |
581 | |
582 /* lock alloc mutex */ | |
583 | |
584 if (ctx->event) { | |
585 ngx_resolver_free_locked(r, ctx->event); | |
586 } | |
587 | |
588 ngx_resolver_free_locked(r, ctx); | |
589 | |
590 /* unlock alloc mutex */ | |
591 | |
592 return NGX_ERROR; | |
593 } | |
594 | |
595 | |
596 void | |
597 ngx_resolve_addr_done(ngx_resolver_ctx_t *ctx) | |
598 { | |
599 in_addr_t addr; | |
600 ngx_resolver_t *r; | |
601 ngx_resolver_ctx_t *w, **p; | |
602 ngx_resolver_node_t *rn; | |
603 | |
604 r = ctx->resolver; | |
605 | |
606 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, | |
607 "resolve addr done: %i", ctx->state); | |
608 | |
609 if (ctx->event && ctx->event->timer_set) { | |
610 ngx_del_timer(ctx->event); | |
611 } | |
612 | |
613 /* lock addr mutex */ | |
614 | |
615 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) { | |
616 | |
617 rn = ngx_resolver_lookup_addr(r, ctx->addr); | |
618 | |
619 if (rn) { | |
620 p = &rn->waiting; | |
621 w = rn->waiting; | |
622 | |
623 while (w) { | |
624 if (w == ctx) { | |
625 *p = w->next; | |
626 | |
627 goto done; | |
628 } | |
629 | |
630 p = &w->next; | |
631 w = w->next; | |
632 } | |
633 } | |
634 | |
635 addr = ntohl(ctx->addr); | |
636 | |
637 ngx_log_error(NGX_LOG_ALERT, r->log, 0, | |
638 "could not cancel %ud.%ud.%ud.%ud resolving", | |
639 (addr >> 24) & 0xff, (addr >> 16) & 0xff, | |
640 (addr >> 8) & 0xff, addr & 0xff); | |
641 } | |
642 | |
643 done: | |
644 | |
645 ngx_resolver_expire(r, &r->addr_rbtree, &r->addr_expire_queue); | |
646 | |
647 /* unlock addr mutex */ | |
648 | |
649 ngx_resolver_free(r, ctx); | |
650 } | |
651 | |
652 | |
653 static void | |
654 ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue) | |
655 { | |
656 time_t now; | |
657 ngx_uint_t i; | |
658 ngx_queue_t *q; | |
659 ngx_resolver_node_t *rn; | |
660 | |
661 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver expire"); | |
662 | |
663 now = ngx_time(); | |
664 | |
665 for (i = 0; i < 2; i++) { | |
666 if (ngx_queue_empty(queue)) { | |
667 return; | |
668 } | |
669 | |
670 q = ngx_queue_last(queue); | |
671 | |
672 rn = ngx_queue_data(q, ngx_resolver_node_t, queue); | |
673 | |
674 if (now <= rn->expire) { | |
675 return; | |
676 } | |
677 | |
678 #if (NGX_DEBUG) | |
679 { | |
680 ngx_str_t s; | |
681 | |
682 s.len = rn->nlen; | |
683 s.data = rn->name; | |
684 | |
685 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, | |
686 "resolver expire \"%V\"", &s); | |
687 } | |
688 #endif | |
689 | |
690 ngx_queue_remove(q); | |
691 | |
692 ngx_rbtree_delete(tree, &rn->node); | |
693 | |
694 ngx_resolver_free_node(r, rn); | |
695 } | |
696 } | |
697 | |
698 | |
699 static ngx_int_t | |
700 ngx_resolver_send_query(ngx_resolver_t *r, ngx_resolver_node_t *rn) | |
701 { | |
702 ssize_t n; | |
703 ngx_udp_connection_t *uc; | |
704 | |
705 uc = r->udp_connection; | |
706 | |
707 if (uc->connection == NULL) { | |
708 if (ngx_udp_connect(uc) != NGX_OK) { | |
709 return NGX_ERROR; | |
710 } | |
711 | |
712 uc->connection->data = r; | |
713 uc->connection->read->handler = ngx_resolver_read_response; | |
714 } | |
715 | |
716 n = ngx_send(uc->connection, rn->query, rn->qlen); | |
717 | |
718 if (n == -1) { | |
719 return NGX_ERROR; | |
720 } | |
721 | |
722 if ((size_t) n != (size_t) rn->qlen) { | |
723 ngx_log_error(NGX_LOG_CRIT, uc->log, 0, "send() incomplete"); | |
724 return NGX_ERROR; | |
725 } | |
726 | |
727 return NGX_OK; | |
728 } | |
729 | |
730 | |
731 static void | |
732 ngx_resolver_resend_handler(ngx_event_t *ev) | |
733 { | |
734 time_t timer, atimer, ntimer; | |
735 ngx_resolver_t *r; | |
736 | |
737 r = ev->data; | |
738 | |
739 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, | |
740 "resolver resend handler"); | |
741 | |
742 /* lock name mutex */ | |
743 | |
744 ntimer = ngx_resolver_resend(r, &r->name_rbtree, &r->name_resend_queue); | |
745 | |
746 /* unlock name mutex */ | |
747 | |
748 /* lock addr mutex */ | |
749 | |
750 atimer = ngx_resolver_resend(r, &r->addr_rbtree, &r->addr_resend_queue); | |
751 | |
752 /* unlock addr mutex */ | |
753 | |
754 if (ntimer == 0) { | |
755 timer = atimer; | |
756 | |
757 } else if (atimer == 0) { | |
758 timer = ntimer; | |
759 | |
760 } else { | |
761 timer = (atimer < ntimer) ? atimer : ntimer; | |
762 } | |
763 | |
764 if (timer) { | |
765 ngx_add_timer(r->event, (ngx_msec_t) (timer * 1000)); | |
766 } | |
767 } | |
768 | |
769 | |
770 static time_t | |
771 ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue) | |
772 { | |
773 time_t now; | |
774 ngx_queue_t *q; | |
775 ngx_resolver_node_t *rn; | |
776 | |
777 now = ngx_time(); | |
778 | |
779 for ( ;; ) { | |
780 if (ngx_queue_empty(queue)) { | |
781 return 0; | |
782 } | |
783 | |
784 q = ngx_queue_last(queue); | |
785 | |
786 rn = ngx_queue_data(q, ngx_resolver_node_t, queue); | |
787 | |
788 if (now < rn->expire) { | |
789 return rn->expire - now; | |
790 } | |
791 | |
792 #if (NGX_DEBUG) | |
793 { | |
794 ngx_str_t s; | |
795 | |
796 s.len = rn->nlen; | |
797 s.data = rn->name; | |
798 | |
799 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0, | |
800 "resolver resend \"%V\" %p", &s, rn->waiting); | |
801 } | |
802 #endif | |
803 | |
804 ngx_queue_remove(q); | |
805 | |
806 if (rn->waiting) { | |
807 | |
808 if (ngx_resolver_send_query(r, rn) == NGX_OK) { | |
809 | |
810 rn->expire = now + r->resend_timeout; | |
811 | |
812 ngx_queue_insert_head(queue, &rn->queue); | |
813 | |
814 continue; | |
815 } | |
816 } | |
817 | |
818 ngx_rbtree_delete(tree, &rn->node); | |
819 | |
820 ngx_resolver_free_node(r, rn); | |
821 } | |
822 } | |
823 | |
824 | |
825 static void | |
826 ngx_resolver_read_response(ngx_event_t *rev) | |
827 { | |
828 ssize_t n; | |
829 ngx_connection_t *c; | |
830 u_char buf[NGX_RESOLVER_UDP_SIZE]; | |
831 | |
832 c = rev->data; | |
833 | |
834 do { | |
835 n = ngx_recv(c, buf, NGX_RESOLVER_UDP_SIZE); | |
836 | |
837 if (n == -1) { | |
838 return; | |
839 } | |
840 | |
841 ngx_resolver_process_response(c->data, buf, n); | |
842 | |
843 } while (rev->ready); | |
844 } | |
845 | |
846 | |
847 static void | |
848 ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf, size_t n) | |
849 { | |
850 char *err; | |
851 size_t len; | |
852 ngx_uint_t i, ident, flags, code, nqs, nan, qtype, qclass; | |
853 ngx_resolver_qs_t *qs; | |
854 ngx_resolver_query_t *query; | |
855 | |
856 if ((size_t) n < sizeof(ngx_resolver_query_t) + 1) { | |
857 goto short_response; | |
858 } | |
859 | |
860 query = (ngx_resolver_query_t *) buf; | |
861 | |
862 ident = (query->ident_hi << 8) + query->ident_lo; | |
863 flags = (query->flags_hi << 8) + query->flags_lo; | |
864 nqs = (query->nqs_hi << 8) + query->nqs_lo; | |
865 nan = (query->nan_hi << 8) + query->nan_lo; | |
866 | |
867 ngx_log_debug6(NGX_LOG_DEBUG_CORE, r->log, 0, | |
868 "resolver DNS response %d fl:%04Xud %d/%d/%d/%d", | |
869 ident, flags, nqs, nan, | |
870 (query->nns_hi << 8) + query->nns_lo, | |
871 (query->nar_hi << 8) + query->nar_lo); | |
872 | |
873 if (!(flags & 0x8000)) { | |
874 ngx_log_error(r->log_level, r->log, 0, | |
875 "invalid DNS response %d fl:%04Xud", ident, flags); | |
876 return; | |
877 } | |
878 | |
879 code = flags & 0x7f; | |
880 | |
881 if (code == NGX_RESOLVE_FORMERR || code > NGX_RESOLVE_REFUSED) { | |
882 ngx_log_error(r->log_level, r->log, 0, | |
883 "DNS error (%d: %s), query id:%d", | |
884 code, ngx_resolver_strerror(code), ident); | |
885 return; | |
886 } | |
887 | |
888 if (nqs != 1) { | |
889 err = "invalid number of questions in DNS response"; | |
890 goto done; | |
891 } | |
892 | |
893 if (code == 0 && nan == 0) { | |
894 err = "no answers in DNS response"; | |
895 goto done; | |
896 } | |
897 | |
898 i = sizeof(ngx_resolver_query_t); | |
899 | |
900 while (i < (ngx_uint_t) n) { | |
901 if (buf[i] == '\0') { | |
902 goto found; | |
903 } | |
904 | |
905 len = buf[i]; | |
906 i += 1 + len; | |
907 } | |
908 | |
909 goto short_response; | |
910 | |
911 found: | |
912 | |
913 if (i++ == 0) { | |
914 err = "zero-length domain name in DNS response"; | |
915 goto done; | |
916 } | |
917 | |
918 if (i + sizeof(ngx_resolver_qs_t) + nan * (2 + sizeof(ngx_resolver_an_t)) | |
919 > (ngx_uint_t) n) | |
920 { | |
921 goto short_response; | |
922 } | |
923 | |
924 qs = (ngx_resolver_qs_t *) &buf[i]; | |
925 | |
926 qtype = (qs->type_hi << 8) + qs->type_lo; | |
927 qclass = (qs->class_hi << 8) + qs->class_lo; | |
928 | |
929 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0, | |
930 "resolver DNS response qt:%d cl:%d", qtype, qclass); | |
931 | |
932 if (qclass != 1) { | |
933 ngx_log_error(r->log_level, r->log, 0, | |
934 "unknown query class %d in DNS response", qclass); | |
935 return; | |
936 } | |
937 | |
938 switch (qtype) { | |
939 | |
940 case NGX_RESOLVE_A: | |
941 | |
942 ngx_resolver_process_a(r, buf, n, ident, code, nan, | |
943 i + sizeof(ngx_resolver_qs_t)); | |
944 | |
945 break; | |
946 | |
947 case NGX_RESOLVE_PTR: | |
948 | |
949 ngx_resolver_process_ptr(r, buf, n, ident, code); | |
950 | |
951 break; | |
952 | |
953 default: | |
954 ngx_log_error(r->log_level, r->log, 0, | |
955 "unknown query type %d in DNS response", qtype); | |
956 return; | |
957 } | |
958 | |
959 return; | |
960 | |
961 short_response: | |
962 | |
963 err = "short dns response"; | |
964 | |
965 done: | |
966 | |
967 ngx_log_error(r->log_level, r->log, 0, err); | |
968 | |
969 return; | |
970 } | |
971 | |
972 | |
973 static void | |
974 ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t last, | |
975 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t ans) | |
976 { | |
977 char *err; | |
978 u_char *cname; | |
979 size_t len; | |
980 uint32_t hash; | |
981 in_addr_t addr, *addrs; | |
982 ngx_str_t name; | |
983 ngx_uint_t qtype, qident, naddrs, a, i, n, start; | |
984 ngx_resolver_an_t *an; | |
985 ngx_resolver_ctx_t *ctx, *next; | |
986 ngx_resolver_node_t *rn; | |
987 | |
988 if (ngx_resolver_copy(r, &name, buf, &buf[12], &buf[last]) != NGX_OK) { | |
989 return; | |
990 } | |
991 | |
992 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver qs:%V", &name); | |
993 | |
994 hash = ngx_crc32_short(name.data, name.len); | |
995 | |
996 /* lock name mutex */ | |
997 | |
998 rn = ngx_resolver_lookup_name(r, &name, hash); | |
999 | |
1000 if (rn == NULL || rn->query == NULL) { | |
1001 ngx_log_error(r->log_level, r->log, 0, | |
1002 "unexpected response for %V", &name); | |
1003 goto failed; | |
1004 } | |
1005 | |
1006 qident = (rn->query[0] << 8) + rn->query[1]; | |
1007 | |
1008 if (ident != qident) { | |
1009 ngx_log_error(r->log_level, r->log, 0, | |
1010 "wrong ident %d response for %V, expect %d", | |
1011 ident, &name, qident); | |
1012 goto failed; | |
1013 } | |
1014 | |
1015 if (code) { | |
1016 next = rn->waiting; | |
1017 rn->waiting = NULL; | |
1018 | |
1019 ngx_queue_remove(&rn->queue); | |
1020 | |
1021 ngx_rbtree_delete(&r->name_rbtree, &rn->node); | |
1022 | |
1023 ngx_resolver_free_node(r, rn); | |
1024 | |
1025 /* unlock name mutex */ | |
1026 | |
1027 while (next) { | |
1028 ctx = next; | |
1029 ctx->state = code; | |
1030 next = ctx->next; | |
1031 | |
1032 ctx->handler(ctx); | |
1033 } | |
1034 | |
1035 return; | |
1036 } | |
1037 | |
1038 i = ans; | |
1039 naddrs = 0; | |
1040 addr = 0; | |
1041 addrs = NULL; | |
1042 cname = NULL; | |
1043 qtype = 0; | |
1044 | |
1045 for (a = 0; a < nan; a++) { | |
1046 | |
1047 start = i; | |
1048 | |
1049 while (i < last) { | |
1050 | |
1051 if (buf[i] & 0xc0) { | |
1052 i += 2; | |
1053 goto found; | |
1054 } | |
1055 | |
1056 if (buf[i] == 0) { | |
1057 i++; | |
1058 goto test_length; | |
1059 } | |
1060 | |
1061 i += 1 + buf[i]; | |
1062 } | |
1063 | |
1064 goto short_response; | |
1065 | |
1066 test_length: | |
1067 | |
1068 if (i - start < 2) { | |
1069 err = "invalid name in dns response"; | |
1070 goto invalid; | |
1071 } | |
1072 | |
1073 found: | |
1074 | |
1075 if (i + sizeof(ngx_resolver_an_t) >= last) { | |
1076 goto short_response; | |
1077 } | |
1078 | |
1079 an = (ngx_resolver_an_t *) &buf[i]; | |
1080 | |
1081 qtype = (an->type_hi << 8) + an->type_lo; | |
1082 len = (an->len_hi << 8) + an->len_lo; | |
1083 | |
1084 if (qtype == NGX_RESOLVE_A) { | |
1085 | |
1086 i += sizeof(ngx_resolver_an_t); | |
1087 | |
1088 if (i + len > last) { | |
1089 goto short_response; | |
1090 } | |
1091 | |
1092 addr = htonl((buf[i] << 24) + (buf[i + 1] << 16) | |
1093 + (buf[i + 2] << 8) + (buf[i + 3])); | |
1094 | |
1095 naddrs++; | |
1096 | |
1097 i += len; | |
1098 | |
1099 } else if (qtype == NGX_RESOLVE_CNAME) { | |
1100 cname = &buf[i] + sizeof(ngx_resolver_an_t); | |
1101 i += sizeof(ngx_resolver_an_t) + len; | |
1102 } | |
1103 } | |
1104 | |
1105 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0, | |
1106 "resolver naddrs:%ui cname:%p", naddrs, cname); | |
1107 | |
1108 if (naddrs) { | |
1109 | |
1110 if (naddrs == 1) { | |
1111 rn->u.addr = addr; | |
1112 | |
1113 } else { | |
1114 | |
1115 addrs = ngx_resolver_alloc(r, naddrs * sizeof(in_addr_t)); | |
1116 if (addrs == NULL) { | |
1117 return; | |
1118 } | |
1119 | |
1120 n = 0; | |
1121 i = ans; | |
1122 | |
1123 for (a = 0; a < nan; a++) { | |
1124 | |
1125 for ( ;; ) { | |
1126 | |
1127 if (buf[i] & 0xc0) { | |
1128 i += 2; | |
1129 goto ok; | |
1130 } | |
1131 | |
1132 if (buf[i] == 0) { | |
1133 i++; | |
1134 goto ok; | |
1135 } | |
1136 | |
1137 i += 1 + buf[i]; | |
1138 } | |
1139 | |
1140 ok: | |
1141 | |
1142 an = (ngx_resolver_an_t *) &buf[i]; | |
1143 | |
1144 qtype = (an->type_hi << 8) + an->type_lo; | |
1145 len = (an->len_hi << 8) + an->len_lo; | |
1146 | |
1147 i += sizeof(ngx_resolver_an_t); | |
1148 | |
1149 if (qtype == NGX_RESOLVE_A) { | |
1150 | |
1151 addrs[n++] = htonl((buf[i] << 24) + (buf[i + 1] << 16) | |
1152 + (buf[i + 2] << 8) + (buf[i + 3])); | |
1153 | |
1154 if (n == naddrs) { | |
1155 break; | |
1156 } | |
1157 } | |
1158 | |
1159 i += len; | |
1160 } | |
1161 | |
1162 rn->u.addrs = addrs; | |
1163 | |
1164 addrs = ngx_resolver_dup(r, rn->u.addrs, | |
1165 naddrs * sizeof(in_addr_t)); | |
1166 if (addrs == NULL) { | |
1167 return; | |
1168 } | |
1169 } | |
1170 | |
1171 rn->naddrs = (u_short) naddrs; | |
1172 | |
1173 ngx_queue_remove(&rn->queue); | |
1174 | |
1175 rn->valid = ngx_time() + r->valid; | |
1176 rn->expire = ngx_time() + r->expire; | |
1177 | |
1178 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue); | |
1179 | |
1180 next = rn->waiting; | |
1181 rn->waiting = NULL; | |
1182 | |
1183 /* unlock name mutex */ | |
1184 | |
1185 while (next) { | |
1186 ctx = next; | |
1187 ctx->state = NGX_OK; | |
1188 ctx->naddrs = naddrs; | |
1189 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs; | |
1190 ctx->addr = addr; | |
1191 next = ctx->next; | |
1192 | |
1193 ctx->handler(ctx); | |
1194 } | |
1195 | |
1196 if (naddrs) { | |
1197 ngx_resolver_free(r, addrs); | |
1198 } | |
1199 | |
1200 return; | |
1201 | |
1202 } else if (cname) { | |
1203 | |
1204 /* CNAME only */ | |
1205 | |
1206 if (ngx_resolver_copy(r, &name, buf, cname, &buf[last]) != NGX_OK) { | |
1207 return; | |
1208 } | |
1209 | |
1210 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, | |
1211 "resolver cname:\"%V\"", &name); | |
1212 | |
1213 rn->cnlen = (u_short) name.len; | |
1214 rn->u.cname = name.data; | |
1215 rn->valid = ngx_time() + r->valid; | |
1216 rn->expire = ngx_time() + r->expire; | |
1217 | |
1218 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue); | |
1219 | |
1220 ctx = rn->waiting; | |
1221 rn->waiting = NULL; | |
1222 | |
1223 if (ctx) { | |
1224 ctx->name = name; | |
1225 | |
1226 (void) ngx_resolve_name_locked(r, ctx); | |
1227 } | |
1228 | |
1229 return; | |
1230 } | |
1231 | |
1232 ngx_log_error(r->log_level, r->log, 0, | |
1233 "no A or CNAME types in DNS responses, unknown query type: %d", | |
1234 qtype); | |
1235 return; | |
1236 | |
1237 short_response: | |
1238 | |
1239 err = "short dns response"; | |
1240 | |
1241 invalid: | |
1242 | |
1243 /* unlock name mutex */ | |
1244 | |
1245 ngx_log_error(r->log_level, r->log, 0, err); | |
1246 | |
1247 return; | |
1248 | |
1249 failed: | |
1250 | |
1251 /* unlock name mutex */ | |
1252 | |
1253 return; | |
1254 } | |
1255 | |
1256 | |
1257 static void | |
1258 ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n, | |
1259 ngx_uint_t ident, ngx_uint_t code) | |
1260 { | |
1261 char *err; | |
1262 size_t len; | |
1263 in_addr_t addr; | |
1264 ngx_int_t digit; | |
1265 ngx_str_t name; | |
1266 ngx_uint_t i, mask, qtype, qclass, qident; | |
1267 ngx_resolver_an_t *an; | |
1268 ngx_resolver_ctx_t *ctx, *next; | |
1269 ngx_resolver_node_t *rn; | |
1270 | |
1271 if (ngx_resolver_copy(r, NULL, buf, &buf[12], &buf[n]) != NGX_OK) { | |
1272 goto invalid_in_addr_arpa; | |
1273 } | |
1274 | |
1275 addr = 0; | |
1276 i = 12; | |
1277 | |
1278 for (mask = 0; mask < 32; mask += 8) { | |
1279 len = buf[i++]; | |
1280 | |
1281 digit = ngx_atoi(&buf[i], len); | |
1282 if (digit == NGX_ERROR || digit > 255) { | |
1283 goto invalid_in_addr_arpa; | |
1284 } | |
1285 | |
1286 addr += digit << mask; | |
1287 i += len; | |
1288 } | |
1289 | |
1290 if (ngx_strcmp(&buf[i], "\7in-addr\4arpa") != 0) { | |
1291 goto invalid_in_addr_arpa; | |
1292 } | |
1293 | |
1294 /* lock addr mutex */ | |
1295 | |
1296 rn = ngx_resolver_lookup_addr(r, addr); | |
1297 | |
1298 if (rn == NULL || rn->query == NULL) { | |
1299 ngx_log_error(r->log_level, r->log, 0, | |
1300 "unexpected response for %ud.%ud.%ud.%ud", | |
1301 (addr >> 24) & 0xff, (addr >> 16) & 0xff, | |
1302 (addr >> 8) & 0xff, addr & 0xff); | |
1303 goto failed; | |
1304 } | |
1305 | |
1306 qident = (rn->query[0] << 8) + rn->query[1]; | |
1307 | |
1308 if (ident != qident) { | |
1309 ngx_log_error(r->log_level, r->log, 0, | |
1310 "wrong ident %d response for %ud.%ud.%ud.%ud, expect %d", | |
1311 ident, (addr >> 24) & 0xff, (addr >> 16) & 0xff, | |
1312 (addr >> 8) & 0xff, addr & 0xff, qident); | |
1313 goto failed; | |
1314 } | |
1315 | |
1316 if (code) { | |
1317 next = rn->waiting; | |
1318 rn->waiting = NULL; | |
1319 | |
1320 ngx_queue_remove(&rn->queue); | |
1321 | |
1322 ngx_rbtree_delete(&r->addr_rbtree, &rn->node); | |
1323 | |
1324 ngx_resolver_free_node(r, rn); | |
1325 | |
1326 /* unlock addr mutex */ | |
1327 | |
1328 while (next) { | |
1329 ctx = next; | |
1330 ctx->state = code; | |
1331 next = ctx->next; | |
1332 | |
1333 ctx->handler(ctx); | |
1334 } | |
1335 | |
1336 return; | |
1337 } | |
1338 | |
1339 i += sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t); | |
1340 | |
1341 if (i + 2 + sizeof(ngx_resolver_an_t) > (ngx_uint_t) n) { | |
1342 goto short_response; | |
1343 } | |
1344 | |
1345 /* compression pointer to "XX.XX.XX.XX.in-addr.arpa */ | |
1346 | |
1347 if (buf[i] != 0xc0 || buf[i + 1] != 0x0c) { | |
1348 err = "invalid in-addr.arpa name in DNS response"; | |
1349 goto invalid; | |
1350 } | |
1351 | |
1352 an = (ngx_resolver_an_t *) &buf[i + 2]; | |
1353 | |
1354 qtype = (an->type_hi << 8) + an->type_lo; | |
1355 qclass = (an->class_hi << 8) + an->class_lo; | |
1356 len = (an->len_hi << 8) + an->len_lo; | |
1357 | |
1358 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0, | |
1359 "resolver qt:%d cl:%d len:%uz", qtype, qclass, len); | |
1360 | |
1361 i += 2 + sizeof(ngx_resolver_an_t); | |
1362 | |
1363 if (i + len > (ngx_uint_t) n) { | |
1364 goto short_response; | |
1365 } | |
1366 | |
1367 len -= 2; | |
1368 | |
1369 if (ngx_resolver_copy(r, &name, buf, &buf[i], &buf[n]) != NGX_OK) { | |
1370 return; | |
1371 } | |
1372 | |
1373 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver an:%V", &name); | |
1374 | |
1375 if (len != (size_t) rn->nlen || ngx_strncmp(name.data, rn->name, len) != 0) | |
1376 { | |
1377 ngx_resolver_free(r, rn->name); | |
1378 rn->name = name.data; | |
1379 | |
1380 name.data = ngx_resolver_dup(r, rn->name, len); | |
1381 if (name.data == NULL) { | |
1382 goto failed; | |
1383 } | |
1384 } | |
1385 | |
1386 ngx_queue_remove(&rn->queue); | |
1387 | |
1388 rn->valid = ngx_time() + r->valid; | |
1389 rn->expire = ngx_time() + r->expire; | |
1390 | |
1391 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue); | |
1392 | |
1393 next = rn->waiting; | |
1394 rn->waiting = NULL; | |
1395 | |
1396 /* unlock addr mutex */ | |
1397 | |
1398 while (next) { | |
1399 ctx = next; | |
1400 ctx->state = NGX_OK; | |
1401 ctx->name = name; | |
1402 next = ctx->next; | |
1403 | |
1404 ctx->handler(ctx); | |
1405 } | |
1406 | |
1407 ngx_resolver_free(r, name.data); | |
1408 | |
1409 return; | |
1410 | |
1411 invalid_in_addr_arpa: | |
1412 | |
1413 ngx_log_error(r->log_level, r->log, 0, | |
1414 "invalid in-addr.arpa name in DNS response"); | |
1415 return; | |
1416 | |
1417 short_response: | |
1418 | |
1419 err = "short DNS response"; | |
1420 | |
1421 invalid: | |
1422 | |
1423 /* unlock addr mutex */ | |
1424 | |
1425 ngx_log_error(r->log_level, r->log, 0, err); | |
1426 | |
1427 return; | |
1428 | |
1429 failed: | |
1430 | |
1431 /* unlock addr mutex */ | |
1432 | |
1433 return; | |
1434 } | |
1435 | |
1436 | |
1437 static ngx_resolver_node_t * | |
1438 ngx_resolver_lookup_name(ngx_resolver_t *r, ngx_str_t *name, uint32_t hash) | |
1439 { | |
1440 ngx_int_t rc; | |
1441 size_t len; | |
1442 ngx_rbtree_node_t *node, *sentinel; | |
1443 ngx_resolver_node_t *rn; | |
1444 | |
1445 node = r->name_rbtree.root; | |
1446 sentinel = r->name_rbtree.sentinel; | |
1447 | |
1448 while (node != sentinel) { | |
1449 | |
1450 if (hash < node->key) { | |
1451 node = node->left; | |
1452 continue; | |
1453 } | |
1454 | |
1455 if (hash > node->key) { | |
1456 node = node->right; | |
1457 continue; | |
1458 } | |
1459 | |
1460 /* hash == node->key */ | |
1461 | |
1462 do { | |
1463 rn = (ngx_resolver_node_t *) node; | |
1464 | |
1465 len = (name->len > (size_t) rn->nlen) ? rn->nlen : name->len; | |
1466 | |
1467 rc = ngx_strncmp(name->data, rn->name, len); | |
1468 | |
1469 if (rc == 0) { | |
1470 return rn; | |
1471 } | |
1472 | |
1473 node = (rc < 0) ? node->left : node->right; | |
1474 | |
1475 } while (node != sentinel && hash == node->key); | |
1476 | |
1477 break; | |
1478 } | |
1479 | |
1480 /* not found */ | |
1481 | |
1482 return NULL; | |
1483 } | |
1484 | |
1485 | |
1486 static ngx_resolver_node_t * | |
1487 ngx_resolver_lookup_addr(ngx_resolver_t *r, in_addr_t addr) | |
1488 { | |
1489 ngx_rbtree_node_t *node, *sentinel; | |
1490 | |
1491 node = r->addr_rbtree.root; | |
1492 sentinel = r->addr_rbtree.sentinel; | |
1493 | |
1494 while (node != sentinel) { | |
1495 | |
1496 if (addr < node->key) { | |
1497 node = node->left; | |
1498 continue; | |
1499 } | |
1500 | |
1501 if (addr > node->key) { | |
1502 node = node->right; | |
1503 continue; | |
1504 } | |
1505 | |
1506 /* addr == node->key */ | |
1507 | |
1508 return (ngx_resolver_node_t *) node; | |
1509 } | |
1510 | |
1511 /* not found */ | |
1512 | |
1513 return NULL; | |
1514 } | |
1515 | |
1516 | |
1517 static void | |
1518 ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp, | |
1519 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel) | |
1520 { | |
1521 size_t len; | |
1522 ngx_rbtree_node_t **p; | |
1523 ngx_resolver_node_t *rn, *rn_temp; | |
1524 | |
1525 for ( ;; ) { | |
1526 | |
1527 if (node->key < temp->key) { | |
1528 | |
1529 p = &temp->left; | |
1530 | |
1531 } else if (node->key > temp->key) { | |
1532 | |
1533 p = &temp->right; | |
1534 | |
1535 } else { /* node->key == temp->key */ | |
1536 | |
1537 rn = (ngx_resolver_node_t *) node; | |
1538 rn_temp = (ngx_resolver_node_t *) temp; | |
1539 | |
1540 len = (rn->nlen > rn_temp->nlen) ? rn_temp->nlen : rn->nlen; | |
1541 | |
1542 p = (ngx_strncmp(rn->name, rn_temp->name, len) < 0) | |
1543 ? &temp->left : &temp->right; | |
1544 } | |
1545 | |
1546 if (*p == sentinel) { | |
1547 break; | |
1548 } | |
1549 | |
1550 temp = *p; | |
1551 } | |
1552 | |
1553 *p = node; | |
1554 node->parent = temp; | |
1555 node->left = sentinel; | |
1556 node->right = sentinel; | |
1557 ngx_rbt_red(node); | |
1558 } | |
1559 | |
1560 | |
1561 static ngx_int_t | |
1562 ngx_resolver_create_name_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx) | |
1563 { | |
1564 u_char *p, *s; | |
1565 size_t len; | |
1566 ngx_uint_t ident; | |
1567 ngx_resolver_qs_t *qs; | |
1568 ngx_resolver_query_t *query; | |
1569 | |
1570 len = sizeof(ngx_resolver_query_t) | |
1571 + 1 + ctx->name.len + 1 + sizeof(ngx_resolver_qs_t); | |
1572 | |
1573 p = ngx_resolver_calloc(ctx->resolver, len); | |
1574 if (p == NULL) { | |
1575 return NGX_ERROR; | |
1576 } | |
1577 | |
1578 rn->qlen = (u_short) len; | |
1579 rn->query = p; | |
1580 | |
1581 query = (ngx_resolver_query_t *) p; | |
1582 | |
1583 ident = ngx_random(); | |
1584 | |
1585 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0, | |
1586 "resolve: \"%V\" %i", &ctx->name, ident & 0xffff); | |
1587 | |
1588 query->ident_hi = (u_char) ((ident >> 8) & 0xff); | |
1589 query->ident_lo = (u_char) (ident & 0xff); | |
1590 | |
1591 /* recursion query */ | |
1592 query->flags_hi = 1; query->flags_lo = 0; | |
1593 | |
1594 /* one question */ | |
1595 query->nqs_hi = 0; query->nqs_lo = 1; | |
1596 query->nan_hi = 0; query->nan_lo = 0; | |
1597 query->nns_hi = 0; query->nns_lo = 0; | |
1598 query->nar_hi = 0; query->nar_lo = 0; | |
1599 | |
1600 p += sizeof(ngx_resolver_query_t) + 1 + ctx->name.len + 1; | |
1601 | |
1602 qs = (ngx_resolver_qs_t *) p; | |
1603 | |
1604 /* query type */ | |
1605 qs->type_hi = 0; qs->type_lo = (u_char) ctx->type; | |
1606 | |
1607 /* IP query class */ | |
1608 qs->class_hi = 0; qs->class_lo = 1; | |
1609 | |
1610 /* convert "www.example.com" to "\3www\7example\3com\0" */ | |
1611 | |
1612 len = 0; | |
1613 p--; | |
1614 *p-- = '\0'; | |
1615 | |
1616 for (s = ctx->name.data + ctx->name.len - 1; s >= ctx->name.data; s--) { | |
1617 if (*s != '.') { | |
1618 *p = *s; | |
1619 len++; | |
1620 | |
1621 } else { | |
1622 *p = (u_char) len; | |
1623 len = 0; | |
1624 } | |
1625 | |
1626 p--; | |
1627 } | |
1628 | |
1629 *p = (u_char) len; | |
1630 | |
1631 return NGX_OK; | |
1632 } | |
1633 | |
1634 | |
1635 /* AF_INET only */ | |
1636 | |
1637 static ngx_int_t | |
1638 ngx_resolver_create_addr_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx) | |
1639 { | |
1640 u_char *p, *d; | |
1641 size_t len; | |
1642 ngx_int_t n; | |
1643 ngx_uint_t ident; | |
1644 ngx_resolver_query_t *query; | |
1645 | |
1646 len = sizeof(ngx_resolver_query_t) | |
1647 + sizeof(".255.255.255.255.in-addr.arpa.") - 1 | |
1648 + sizeof(ngx_resolver_qs_t); | |
1649 | |
1650 p = ngx_resolver_calloc(ctx->resolver, len); | |
1651 if (p == NULL) { | |
1652 return NGX_ERROR; | |
1653 } | |
1654 | |
1655 rn->query = p; | |
1656 query = (ngx_resolver_query_t *) p; | |
1657 | |
1658 ident = ngx_random(); | |
1659 | |
1660 query->ident_hi = (u_char) ((ident >> 8) & 0xff); | |
1661 query->ident_lo = (u_char) (ident & 0xff); | |
1662 | |
1663 /* recursion query */ | |
1664 query->flags_hi = 1; query->flags_lo = 0; | |
1665 | |
1666 /* one question */ | |
1667 query->nqs_hi = 0; query->nqs_lo = 1; | |
1668 query->nan_hi = 0; query->nan_lo = 0; | |
1669 query->nns_hi = 0; query->nns_lo = 0; | |
1670 query->nar_hi = 0; query->nar_lo = 0; | |
1671 | |
1672 p += sizeof(ngx_resolver_query_t); | |
1673 | |
1674 for (n = 0; n < 32; n += 8){ | |
1675 d = ngx_sprintf(&p[1], "%ud", (ctx->addr >> n) & 0xff); | |
1676 *p = (u_char) (d - &p[1]); | |
1677 p = d; | |
1678 } | |
1679 | |
1680 /* query type "PTR", IP query class */ | |
1681 ngx_memcpy(p, "\7in-addr\4arpa\0\0\14\0\1", 18); | |
1682 | |
1683 rn->qlen = (u_short) | |
1684 (p + sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t) | |
1685 - rn->query); | |
1686 | |
1687 return NGX_OK; | |
1688 } | |
1689 | |
1690 | |
1691 static ngx_int_t | |
1692 ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name, u_char *buf, u_char *src, | |
1693 u_char *last) | |
1694 { | |
1695 char *err; | |
1696 u_char *p, *dst; | |
1697 ssize_t len; | |
1698 ngx_uint_t i, n; | |
1699 | |
1700 p = src; | |
1701 len = -1; | |
1702 | |
1703 /* | |
1704 * compression pointers allow to create endless loop, so we set limit; | |
1705 * 128 pointers should be enough to store 255-byte name | |
1706 */ | |
1707 | |
1708 for (i = 0; i < 128; i++) { | |
1709 n = *p++; | |
1710 | |
1711 if (n == 0) { | |
1712 goto done; | |
1713 } | |
1714 | |
1715 if (n & 0xc0) { | |
1716 n = (n & 0x3f << 8) + *p; | |
1717 p = &buf[n]; | |
1718 | |
1719 } else { | |
1720 len += 1 + n; | |
1721 p = &p[n]; | |
1722 } | |
1723 | |
1724 if (p >= last) { | |
1725 err = "name is out of response"; | |
1726 goto invalid; | |
1727 } | |
1728 } | |
1729 | |
1730 err = "compression pointers loop"; | |
1731 | |
1732 invalid: | |
1733 | |
1734 ngx_log_error(r->log_level, r->log, 0, err); | |
1735 | |
1736 return NGX_ERROR; | |
1737 | |
1738 done: | |
1739 | |
1740 if (name == NULL) { | |
1741 return NGX_OK; | |
1742 } | |
1743 | |
1744 dst = ngx_resolver_alloc(r, len); | |
1745 if (dst == NULL) { | |
1746 return NGX_ERROR; | |
1747 } | |
1748 | |
1749 name->data = dst; | |
1750 | |
1751 n = *src++; | |
1752 | |
1753 for ( ;; ) { | |
1754 if (n != 0xc0) { | |
1755 ngx_memcpy(dst, src, n); | |
1756 dst += n; | |
1757 src += n; | |
1758 | |
1759 n = *src++; | |
1760 | |
1761 if (n != 0) { | |
1762 *dst++ = '.'; | |
1763 } | |
1764 | |
1765 } else { | |
1766 n = (n & 0x3f << 8) + *src; | |
1767 src = &buf[n]; | |
1768 | |
1769 n = *src++; | |
1770 } | |
1771 | |
1772 if (n == 0) { | |
1773 name->len = dst - name->data; | |
1774 return NGX_OK; | |
1775 } | |
1776 } | |
1777 } | |
1778 | |
1779 | |
1780 static void | |
1781 ngx_resolver_timeout_handler(ngx_event_t *ev) | |
1782 { | |
1783 ngx_resolver_ctx_t *ctx; | |
1784 | |
1785 ctx = ev->data; | |
1786 | |
1787 ctx->state = NGX_RESOLVE_TIMEDOUT; | |
1788 | |
1789 ctx->handler(ctx); | |
1790 } | |
1791 | |
1792 | |
1793 static void | |
1794 ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn) | |
1795 { | |
1796 /* lock alloc mutex */ | |
1797 | |
1798 if (rn->query) { | |
1799 ngx_resolver_free_locked(r, rn->query); | |
1800 } | |
1801 | |
1802 if (rn->name) { | |
1803 ngx_resolver_free_locked(r, rn->name); | |
1804 } | |
1805 | |
1806 if (rn->cnlen) { | |
1807 ngx_resolver_free_locked(r, rn->u.cname); | |
1808 } | |
1809 | |
1810 if (rn->naddrs > 1) { | |
1811 ngx_resolver_free_locked(r, rn->u.addrs); | |
1812 } | |
1813 | |
1814 ngx_resolver_free_locked(r, rn); | |
1815 | |
1816 /* unlock alloc mutex */ | |
1817 } | |
1818 | |
1819 | |
1820 static void * | |
1821 ngx_resolver_alloc(ngx_resolver_t *r, size_t size) | |
1822 { | |
1823 u_char *p; | |
1824 | |
1825 /* lock alloc mutex */ | |
1826 | |
1827 p = ngx_alloc(size, r->log); | |
1828 | |
1829 /* unlock alloc mutex */ | |
1830 | |
1831 return p; | |
1832 } | |
1833 | |
1834 | |
1835 void * | |
1836 ngx_resolver_calloc(ngx_resolver_t *r, size_t size) | |
1837 { | |
1838 u_char *p; | |
1839 | |
1840 p = ngx_resolver_alloc(r, size); | |
1841 | |
1842 if (p) { | |
1843 ngx_memzero(p, size); | |
1844 } | |
1845 | |
1846 return p; | |
1847 } | |
1848 | |
1849 | |
1850 static void | |
1851 ngx_resolver_free(ngx_resolver_t *r, void *p) | |
1852 { | |
1853 /* lock alloc mutex */ | |
1854 | |
1855 ngx_free(p); | |
1856 | |
1857 /* unlock alloc mutex */ | |
1858 } | |
1859 | |
1860 | |
1861 static void | |
1862 ngx_resolver_free_locked(ngx_resolver_t *r, void *p) | |
1863 { | |
1864 ngx_free(p); | |
1865 } | |
1866 | |
1867 | |
1868 static void * | |
1869 ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size) | |
1870 { | |
1871 void *dst; | |
1872 | |
1873 dst = ngx_resolver_alloc(r, size); | |
1874 | |
1875 if (dst == NULL) { | |
1876 return dst; | |
1877 } | |
1878 | |
1879 ngx_memcpy(dst, src, size); | |
1880 | |
1881 return dst; | |
1882 } | |
1883 | |
1884 | |
1885 char * | |
1886 ngx_resolver_strerror(ngx_int_t err) | |
1887 { | |
1888 static char *errors[] = { | |
1889 "Format error", /* FORMERR */ | |
1890 "Server failure", /* SERVFAIL */ | |
1891 "Host not found", /* NXDOMAIN */ | |
1892 "Unimplemented", /* NOTIMP */ | |
1893 "Operation refused" /* REFUSED */ | |
1894 }; | |
1895 | |
1896 if (err > 0 && err < 6) { | |
1897 return errors[err - 1]; | |
1898 } | |
1899 | |
1900 if (err == NGX_RESOLVE_TIMEDOUT) { | |
1901 return "Operation timed out"; | |
1902 } | |
1903 | |
1904 return "Unknown error"; | |
1905 } | |
1906 | |
1907 | |
1908 ngx_int_t | |
1909 ngx_udp_connect(ngx_udp_connection_t *uc) | |
1910 { | |
1911 int rc; | |
1912 ngx_int_t event; | |
1913 ngx_event_t *rev, *wev; | |
1914 ngx_socket_t s; | |
1915 ngx_connection_t *c; | |
1916 | |
1917 s = ngx_socket(AF_INET, SOCK_DGRAM, 0); | |
1918 | |
1919 ngx_log_debug1(NGX_LOG_DEBUG_EVENT, uc->log, 0, "UDP socket %d", s); | |
1920 | |
1921 if (s == -1) { | |
1922 ngx_log_error(NGX_LOG_ALERT, uc->log, ngx_socket_errno, | |
1923 ngx_socket_n " failed"); | |
1924 return NGX_ERROR; | |
1925 } | |
1926 | |
1927 c = ngx_get_connection(s, uc->log); | |
1928 | |
1929 if (c == NULL) { | |
1930 if (ngx_close_socket(s) == -1) { | |
1931 ngx_log_error(NGX_LOG_ALERT, uc->log, ngx_socket_errno, | |
1932 ngx_close_socket_n "failed"); | |
1933 } | |
1934 | |
1935 return NGX_ERROR; | |
1936 } | |
1937 | |
1938 if (ngx_nonblocking(s) == -1) { | |
1939 ngx_log_error(NGX_LOG_ALERT, uc->log, ngx_socket_errno, | |
1940 ngx_nonblocking_n " failed"); | |
1941 | |
1942 ngx_free_connection(c); | |
1943 | |
1944 if (ngx_close_socket(s) == -1) { | |
1945 ngx_log_error(NGX_LOG_ALERT, uc->log, ngx_socket_errno, | |
1946 ngx_close_socket_n " failed"); | |
1947 } | |
1948 | |
1949 return NGX_ERROR; | |
1950 } | |
1951 | |
1952 rev = c->read; | |
1953 wev = c->write; | |
1954 | |
1955 rev->log = uc->log; | |
1956 wev->log = uc->log; | |
1957 | |
1958 uc->connection = c; | |
1959 | |
1960 c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1); | |
1961 | |
1962 #if (NGX_THREADS) | |
1963 | |
1964 /* TODO: lock event when call completion handler */ | |
1965 | |
1966 rev->lock = &c->lock; | |
1967 wev->lock = &c->lock; | |
1968 rev->own_lock = &c->lock; | |
1969 wev->own_lock = &c->lock; | |
1970 | |
1971 #endif | |
1972 | |
1973 ngx_log_debug3(NGX_LOG_DEBUG_EVENT, uc->log, 0, | |
1974 "connect to %V, fd:%d #%d", &uc->server, s, c->number); | |
1975 | |
1976 rc = connect(s, uc->sockaddr, uc->socklen); | |
1977 | |
1978 /* TODO: aio, iocp */ | |
1979 | |
1980 if (rc == -1) { | |
1981 ngx_log_error(NGX_LOG_CRIT, uc->log, ngx_socket_errno, | |
1982 "connect() to %V failed", &uc->server); | |
1983 | |
1984 return NGX_ERROR; | |
1985 } | |
1986 | |
1987 /* UDP sockets are always ready to write */ | |
1988 wev->ready = 1; | |
1989 | |
1990 if (ngx_add_event) { | |
1991 | |
1992 event = (ngx_event_flags & NGX_USE_CLEAR_EVENT) ? | |
1993 /* kqueue, epoll */ NGX_CLEAR_EVENT: | |
1994 /* select, poll, /dev/poll */ NGX_LEVEL_EVENT; | |
1995 /* eventport event type has no meaning: oneshot only */ | |
1996 | |
1997 if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) { | |
1998 return NGX_ERROR; | |
1999 } | |
2000 | |
2001 } else { | |
2002 /* rtsig */ | |
2003 | |
2004 if (ngx_add_conn(c) == NGX_ERROR) { | |
2005 return NGX_ERROR; | |
2006 } | |
2007 } | |
2008 | |
2009 return NGX_OK; | |
2010 } |