350
|
1
|
|
2 /*
|
|
3 * Copyright (C) Igor Sysoev
|
660
|
4 * Copyright (C) Nginx, Inc.
|
350
|
5 */
|
|
6
|
|
7
|
|
8 #include <ngx_config.h>
|
|
9 #include <ngx_core.h>
|
|
10 #include <ngx_event.h>
|
|
11
|
|
12
|
|
13 #define NGX_RESOLVER_UDP_SIZE 4096
|
|
14
|
|
15
|
|
16 typedef struct {
|
|
17 u_char ident_hi;
|
|
18 u_char ident_lo;
|
|
19 u_char flags_hi;
|
|
20 u_char flags_lo;
|
|
21 u_char nqs_hi;
|
|
22 u_char nqs_lo;
|
|
23 u_char nan_hi;
|
|
24 u_char nan_lo;
|
|
25 u_char nns_hi;
|
|
26 u_char nns_lo;
|
|
27 u_char nar_hi;
|
|
28 u_char nar_lo;
|
|
29 } ngx_resolver_query_t;
|
|
30
|
|
31
|
|
32 typedef struct {
|
|
33 u_char type_hi;
|
|
34 u_char type_lo;
|
|
35 u_char class_hi;
|
|
36 u_char class_lo;
|
|
37 } ngx_resolver_qs_t;
|
|
38
|
|
39
|
|
40 typedef struct {
|
|
41 u_char type_hi;
|
|
42 u_char type_lo;
|
|
43 u_char class_hi;
|
|
44 u_char class_lo;
|
|
45 u_char ttl[4];
|
|
46 u_char len_hi;
|
|
47 u_char len_lo;
|
|
48 } ngx_resolver_an_t;
|
|
49
|
|
50
|
|
51 ngx_int_t ngx_udp_connect(ngx_udp_connection_t *uc);
|
|
52
|
|
53
|
366
|
54 static void ngx_resolver_cleanup(void *data);
|
|
55 static void ngx_resolver_cleanup_tree(ngx_resolver_t *r, ngx_rbtree_t *tree);
|
350
|
56 static ngx_int_t ngx_resolve_name_locked(ngx_resolver_t *r,
|
|
57 ngx_resolver_ctx_t *ctx);
|
|
58 static void ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree,
|
|
59 ngx_queue_t *queue);
|
|
60 static ngx_int_t ngx_resolver_send_query(ngx_resolver_t *r,
|
|
61 ngx_resolver_node_t *rn);
|
|
62 static ngx_int_t ngx_resolver_create_name_query(ngx_resolver_node_t *rn,
|
|
63 ngx_resolver_ctx_t *ctx);
|
|
64 static ngx_int_t ngx_resolver_create_addr_query(ngx_resolver_node_t *rn,
|
|
65 ngx_resolver_ctx_t *ctx);
|
|
66 static void ngx_resolver_resend_handler(ngx_event_t *ev);
|
|
67 static time_t ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree,
|
|
68 ngx_queue_t *queue);
|
|
69 static void ngx_resolver_read_response(ngx_event_t *rev);
|
|
70 static void ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf,
|
|
71 size_t n);
|
|
72 static void ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t n,
|
356
|
73 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t ans);
|
350
|
74 static void ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n,
|
356
|
75 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan);
|
350
|
76 static ngx_resolver_node_t *ngx_resolver_lookup_name(ngx_resolver_t *r,
|
|
77 ngx_str_t *name, uint32_t hash);
|
|
78 static ngx_resolver_node_t *ngx_resolver_lookup_addr(ngx_resolver_t *r,
|
|
79 in_addr_t addr);
|
|
80 static void ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp,
|
|
81 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel);
|
|
82 static ngx_int_t ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name,
|
|
83 u_char *buf, u_char *src, u_char *last);
|
|
84 static void ngx_resolver_timeout_handler(ngx_event_t *ev);
|
|
85 static void ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn);
|
|
86 static void *ngx_resolver_alloc(ngx_resolver_t *r, size_t size);
|
366
|
87 static void *ngx_resolver_calloc(ngx_resolver_t *r, size_t size);
|
350
|
88 static void ngx_resolver_free(ngx_resolver_t *r, void *p);
|
|
89 static void ngx_resolver_free_locked(ngx_resolver_t *r, void *p);
|
|
90 static void *ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size);
|
560
|
91 static u_char *ngx_resolver_log_error(ngx_log_t *log, u_char *buf, size_t len);
|
350
|
92
|
|
93
|
|
94 ngx_resolver_t *
|
646
|
95 ngx_resolver_create(ngx_conf_t *cf, ngx_str_t *names, ngx_uint_t n)
|
350
|
96 {
|
650
|
97 ngx_str_t s;
|
646
|
98 ngx_url_t u;
|
|
99 ngx_uint_t i;
|
350
|
100 ngx_resolver_t *r;
|
366
|
101 ngx_pool_cleanup_t *cln;
|
350
|
102 ngx_udp_connection_t *uc;
|
|
103
|
366
|
104 cln = ngx_pool_cleanup_add(cf->pool, 0);
|
|
105 if (cln == NULL) {
|
|
106 return NULL;
|
|
107 }
|
|
108
|
|
109 cln->handler = ngx_resolver_cleanup;
|
|
110
|
|
111 r = ngx_calloc(sizeof(ngx_resolver_t), cf->log);
|
350
|
112 if (r == NULL) {
|
|
113 return NULL;
|
|
114 }
|
|
115
|
646
|
116 if (n) {
|
|
117 if (ngx_array_init(&r->udp_connections, cf->pool, n,
|
|
118 sizeof(ngx_udp_connection_t))
|
|
119 != NGX_OK)
|
|
120 {
|
|
121 return NULL;
|
|
122 }
|
|
123 }
|
|
124
|
366
|
125 cln->data = r;
|
|
126
|
|
127 r->event = ngx_calloc(sizeof(ngx_event_t), cf->log);
|
350
|
128 if (r->event == NULL) {
|
|
129 return NULL;
|
|
130 }
|
|
131
|
354
|
132 ngx_rbtree_init(&r->name_rbtree, &r->name_sentinel,
|
|
133 ngx_resolver_rbtree_insert_value);
|
|
134
|
|
135 ngx_rbtree_init(&r->addr_rbtree, &r->addr_sentinel,
|
|
136 ngx_rbtree_insert_value);
|
|
137
|
|
138 ngx_queue_init(&r->name_resend_queue);
|
|
139 ngx_queue_init(&r->addr_resend_queue);
|
|
140
|
|
141 ngx_queue_init(&r->name_expire_queue);
|
|
142 ngx_queue_init(&r->addr_expire_queue);
|
350
|
143
|
|
144 r->event->handler = ngx_resolver_resend_handler;
|
|
145 r->event->data = r;
|
484
|
146 r->event->log = &cf->cycle->new_log;
|
350
|
147 r->ident = -1;
|
|
148
|
|
149 r->resend_timeout = 5;
|
|
150 r->expire = 30;
|
650
|
151 r->valid = 0;
|
350
|
152
|
484
|
153 r->log = &cf->cycle->new_log;
|
598
|
154 r->log_level = NGX_LOG_ERR;
|
350
|
155
|
646
|
156 for (i = 0; i < n; i++) {
|
650
|
157 if (ngx_strncmp(names[i].data, "valid=", 6) == 0) {
|
|
158 s.len = names[i].len - 6;
|
|
159 s.data = names[i].data + 6;
|
|
160
|
|
161 r->valid = ngx_parse_time(&s, 1);
|
|
162
|
662
|
163 if (r->valid == (time_t) NGX_ERROR) {
|
650
|
164 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
165 "invalid parameter: %V", &names[i]);
|
|
166 return NULL;
|
|
167 }
|
|
168
|
|
169 continue;
|
|
170 }
|
|
171
|
646
|
172 ngx_memzero(&u, sizeof(ngx_url_t));
|
|
173
|
|
174 u.host = names[i];
|
|
175 u.port = 53;
|
|
176
|
|
177 if (ngx_inet_resolve_host(cf->pool, &u) != NGX_OK) {
|
|
178 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%V: %s", &u.host, u.err);
|
|
179 return NULL;
|
|
180 }
|
|
181
|
|
182 uc = ngx_array_push(&r->udp_connections);
|
354
|
183 if (uc == NULL) {
|
|
184 return NULL;
|
|
185 }
|
|
186
|
646
|
187 ngx_memzero(uc, sizeof(ngx_udp_connection_t));
|
|
188
|
|
189 uc->sockaddr = u.addrs->sockaddr;
|
|
190 uc->socklen = u.addrs->socklen;
|
|
191 uc->server = u.addrs->name;
|
354
|
192 }
|
350
|
193
|
|
194 return r;
|
|
195 }
|
|
196
|
|
197
|
366
|
198 static void
|
|
199 ngx_resolver_cleanup(void *data)
|
|
200 {
|
|
201 ngx_resolver_t *r = data;
|
|
202
|
646
|
203 ngx_uint_t i;
|
|
204 ngx_udp_connection_t *uc;
|
|
205
|
366
|
206 if (r) {
|
|
207 ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0,
|
|
208 "cleanup resolver");
|
|
209
|
|
210 ngx_resolver_cleanup_tree(r, &r->name_rbtree);
|
|
211
|
|
212 ngx_resolver_cleanup_tree(r, &r->addr_rbtree);
|
|
213
|
|
214 if (r->event) {
|
|
215 ngx_free(r->event);
|
|
216 }
|
|
217
|
646
|
218
|
|
219 uc = r->udp_connections.elts;
|
|
220
|
|
221 for (i = 0; i < r->udp_connections.nelts; i++) {
|
|
222 if (uc[i].connection) {
|
|
223 ngx_close_connection(uc[i].connection);
|
366
|
224 }
|
|
225 }
|
|
226
|
|
227 ngx_free(r);
|
|
228 }
|
|
229 }
|
|
230
|
|
231
|
|
232 static void
|
|
233 ngx_resolver_cleanup_tree(ngx_resolver_t *r, ngx_rbtree_t *tree)
|
|
234 {
|
|
235 ngx_resolver_ctx_t *ctx, *next;
|
|
236 ngx_resolver_node_t *rn;
|
|
237
|
|
238 while (tree->root != tree->sentinel) {
|
|
239
|
|
240 rn = (ngx_resolver_node_t *) ngx_rbtree_min(tree->root, tree->sentinel);
|
|
241
|
|
242 ngx_queue_remove(&rn->queue);
|
|
243
|
|
244 for (ctx = rn->waiting; ctx; ctx = next) {
|
376
|
245 next = ctx->next;
|
366
|
246
|
|
247 if (ctx->event) {
|
|
248 ngx_resolver_free(r, ctx->event);
|
|
249 }
|
|
250
|
|
251 ngx_resolver_free(r, ctx);
|
|
252 }
|
|
253
|
|
254 ngx_rbtree_delete(tree, &rn->node);
|
|
255
|
|
256 ngx_resolver_free_node(r, rn);
|
|
257 }
|
|
258 }
|
|
259
|
|
260
|
350
|
261 ngx_resolver_ctx_t *
|
|
262 ngx_resolve_start(ngx_resolver_t *r, ngx_resolver_ctx_t *temp)
|
|
263 {
|
|
264 in_addr_t addr;
|
|
265 ngx_resolver_ctx_t *ctx;
|
|
266
|
|
267 if (temp) {
|
|
268 addr = ngx_inet_addr(temp->name.data, temp->name.len);
|
|
269
|
|
270 if (addr != INADDR_NONE) {
|
|
271 temp->resolver = r;
|
|
272 temp->state = NGX_OK;
|
|
273 temp->naddrs = 1;
|
|
274 temp->addrs = &temp->addr;
|
|
275 temp->addr = addr;
|
|
276 temp->quick = 1;
|
|
277
|
|
278 return temp;
|
|
279 }
|
|
280 }
|
|
281
|
646
|
282 if (r->udp_connections.nelts == 0) {
|
354
|
283 return NGX_NO_RESOLVER;
|
|
284 }
|
|
285
|
350
|
286 ctx = ngx_resolver_calloc(r, sizeof(ngx_resolver_ctx_t));
|
|
287
|
|
288 if (ctx) {
|
|
289 ctx->resolver = r;
|
|
290 }
|
|
291
|
|
292 return ctx;
|
|
293 }
|
|
294
|
|
295
|
|
296 ngx_int_t
|
|
297 ngx_resolve_name(ngx_resolver_ctx_t *ctx)
|
|
298 {
|
|
299 ngx_int_t rc;
|
|
300 ngx_resolver_t *r;
|
|
301
|
|
302 r = ctx->resolver;
|
|
303
|
|
304 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
305 "resolve: \"%V\"", &ctx->name);
|
|
306
|
|
307 if (ctx->quick) {
|
|
308 ctx->handler(ctx);
|
|
309 return NGX_OK;
|
|
310 }
|
|
311
|
|
312 /* lock name mutex */
|
|
313
|
|
314 rc = ngx_resolve_name_locked(r, ctx);
|
|
315
|
|
316 if (rc == NGX_OK) {
|
|
317 return NGX_OK;
|
|
318 }
|
|
319
|
|
320 /* unlock name mutex */
|
|
321
|
|
322 if (rc == NGX_AGAIN) {
|
|
323 return NGX_OK;
|
|
324 }
|
|
325
|
366
|
326 /* NGX_ERROR */
|
350
|
327
|
|
328 if (ctx->event) {
|
366
|
329 ngx_resolver_free(r, ctx->event);
|
350
|
330 }
|
|
331
|
366
|
332 ngx_resolver_free(r, ctx);
|
350
|
333
|
|
334 return NGX_ERROR;
|
|
335 }
|
|
336
|
|
337
|
|
338 void
|
|
339 ngx_resolve_name_done(ngx_resolver_ctx_t *ctx)
|
|
340 {
|
|
341 uint32_t hash;
|
|
342 ngx_resolver_t *r;
|
|
343 ngx_resolver_ctx_t *w, **p;
|
|
344 ngx_resolver_node_t *rn;
|
|
345
|
|
346 r = ctx->resolver;
|
|
347
|
|
348 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
349 "resolve name done: %i", ctx->state);
|
|
350
|
|
351 if (ctx->quick) {
|
|
352 return;
|
|
353 }
|
|
354
|
|
355 if (ctx->event && ctx->event->timer_set) {
|
|
356 ngx_del_timer(ctx->event);
|
|
357 }
|
|
358
|
|
359 /* lock name mutex */
|
|
360
|
|
361 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) {
|
|
362
|
|
363 hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
|
|
364
|
|
365 rn = ngx_resolver_lookup_name(r, &ctx->name, hash);
|
|
366
|
|
367 if (rn) {
|
|
368 p = &rn->waiting;
|
|
369 w = rn->waiting;
|
|
370
|
|
371 while (w) {
|
|
372 if (w == ctx) {
|
|
373 *p = w->next;
|
|
374
|
|
375 goto done;
|
|
376 }
|
|
377
|
|
378 p = &w->next;
|
|
379 w = w->next;
|
|
380 }
|
|
381 }
|
|
382
|
|
383 ngx_log_error(NGX_LOG_ALERT, r->log, 0,
|
|
384 "could not cancel %V resolving", &ctx->name);
|
|
385 }
|
|
386
|
|
387 done:
|
|
388
|
|
389 ngx_resolver_expire(r, &r->name_rbtree, &r->name_expire_queue);
|
|
390
|
|
391 /* unlock name mutex */
|
|
392
|
366
|
393 /* lock alloc mutex */
|
|
394
|
|
395 if (ctx->event) {
|
|
396 ngx_resolver_free_locked(r, ctx->event);
|
|
397 }
|
|
398
|
|
399 ngx_resolver_free_locked(r, ctx);
|
|
400
|
|
401 /* unlock alloc mutex */
|
350
|
402 }
|
|
403
|
|
404
|
|
405 /* NGX_RESOLVE_A only */
|
|
406
|
|
407 static ngx_int_t
|
|
408 ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx)
|
|
409 {
|
|
410 uint32_t hash;
|
|
411 in_addr_t addr, *addrs;
|
372
|
412 ngx_int_t rc;
|
350
|
413 ngx_uint_t naddrs;
|
|
414 ngx_resolver_ctx_t *next;
|
|
415 ngx_resolver_node_t *rn;
|
|
416
|
|
417 hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
|
|
418
|
|
419 rn = ngx_resolver_lookup_name(r, &ctx->name, hash);
|
|
420
|
|
421 if (rn) {
|
|
422
|
|
423 if (rn->valid >= ngx_time()) {
|
|
424
|
|
425 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached");
|
|
426
|
|
427 ngx_queue_remove(&rn->queue);
|
|
428
|
|
429 rn->expire = ngx_time() + r->expire;
|
|
430
|
|
431 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
432
|
|
433 naddrs = rn->naddrs;
|
|
434
|
|
435 if (naddrs) {
|
|
436
|
|
437 /* NGX_RESOLVE_A answer */
|
|
438
|
|
439 if (naddrs != 1) {
|
|
440 addr = 0;
|
|
441 addrs = ngx_resolver_dup(r, rn->u.addrs,
|
|
442 naddrs * sizeof(in_addr_t));
|
|
443 if (addrs == NULL) {
|
|
444 return NGX_ERROR;
|
|
445 }
|
|
446
|
|
447 } else {
|
|
448 addr = rn->u.addr;
|
|
449 addrs = NULL;
|
|
450 }
|
|
451
|
|
452 ctx->next = rn->waiting;
|
|
453 rn->waiting = NULL;
|
|
454
|
|
455 /* unlock name mutex */
|
|
456
|
|
457 do {
|
|
458 ctx->state = NGX_OK;
|
|
459 ctx->naddrs = naddrs;
|
|
460 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs;
|
|
461 ctx->addr = addr;
|
|
462 next = ctx->next;
|
|
463
|
|
464 ctx->handler(ctx);
|
|
465
|
|
466 ctx = next;
|
|
467 } while (ctx);
|
|
468
|
|
469 if (addrs) {
|
|
470 ngx_resolver_free(r, addrs);
|
|
471 }
|
|
472
|
|
473 return NGX_OK;
|
|
474 }
|
|
475
|
|
476 /* NGX_RESOLVE_CNAME */
|
|
477
|
372
|
478 if (ctx->recursion++ < NGX_RESOLVER_MAX_RECURSION) {
|
|
479
|
|
480 ctx->name.len = rn->cnlen;
|
|
481 ctx->name.data = rn->u.cname;
|
|
482
|
|
483 return ngx_resolve_name_locked(r, ctx);
|
|
484 }
|
|
485
|
|
486 ctx->next = rn->waiting;
|
|
487 rn->waiting = NULL;
|
|
488
|
|
489 /* unlock name mutex */
|
|
490
|
|
491 do {
|
|
492 ctx->state = NGX_RESOLVE_NXDOMAIN;
|
|
493 next = ctx->next;
|
|
494
|
|
495 ctx->handler(ctx);
|
|
496
|
|
497 ctx = next;
|
|
498 } while (ctx);
|
|
499
|
|
500 return NGX_OK;
|
350
|
501 }
|
|
502
|
|
503 if (rn->waiting) {
|
|
504
|
|
505 ctx->next = rn->waiting;
|
|
506 rn->waiting = ctx;
|
542
|
507 ctx->state = NGX_AGAIN;
|
350
|
508
|
|
509 return NGX_AGAIN;
|
|
510 }
|
|
511
|
|
512 ngx_queue_remove(&rn->queue);
|
|
513
|
|
514 /* lock alloc mutex */
|
|
515
|
674
|
516 if (rn->query) {
|
|
517 ngx_resolver_free_locked(r, rn->query);
|
|
518 rn->query = NULL;
|
|
519 }
|
350
|
520
|
|
521 if (rn->cnlen) {
|
|
522 ngx_resolver_free_locked(r, rn->u.cname);
|
|
523 }
|
|
524
|
|
525 if (rn->naddrs > 1) {
|
|
526 ngx_resolver_free_locked(r, rn->u.addrs);
|
|
527 }
|
|
528
|
|
529 /* unlock alloc mutex */
|
|
530
|
|
531 } else {
|
|
532
|
|
533 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t));
|
|
534 if (rn == NULL) {
|
|
535 return NGX_ERROR;
|
|
536 }
|
|
537
|
|
538 rn->name = ngx_resolver_dup(r, ctx->name.data, ctx->name.len);
|
|
539 if (rn->name == NULL) {
|
|
540 ngx_resolver_free(r, rn);
|
|
541 return NGX_ERROR;
|
|
542 }
|
|
543
|
|
544 rn->node.key = hash;
|
|
545 rn->nlen = (u_short) ctx->name.len;
|
372
|
546 rn->query = NULL;
|
350
|
547
|
|
548 ngx_rbtree_insert(&r->name_rbtree, &rn->node);
|
|
549 }
|
|
550
|
372
|
551 rc = ngx_resolver_create_name_query(rn, ctx);
|
|
552
|
|
553 if (rc == NGX_ERROR) {
|
350
|
554 goto failed;
|
|
555 }
|
|
556
|
372
|
557 if (rc == NGX_DECLINED) {
|
|
558 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
559
|
|
560 ngx_resolver_free(r, rn->query);
|
|
561 ngx_resolver_free(r, rn->name);
|
|
562 ngx_resolver_free(r, rn);
|
|
563
|
|
564 ctx->state = NGX_RESOLVE_NXDOMAIN;
|
|
565 ctx->handler(ctx);
|
|
566
|
|
567 return NGX_OK;
|
|
568 }
|
|
569
|
350
|
570 if (ngx_resolver_send_query(r, rn) != NGX_OK) {
|
|
571 goto failed;
|
|
572 }
|
|
573
|
|
574 if (ctx->event == NULL) {
|
|
575 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t));
|
|
576 if (ctx->event == NULL) {
|
|
577 goto failed;
|
|
578 }
|
|
579
|
|
580 ctx->event->handler = ngx_resolver_timeout_handler;
|
|
581 ctx->event->data = ctx;
|
|
582 ctx->event->log = r->log;
|
|
583 ctx->ident = -1;
|
|
584
|
|
585 ngx_add_timer(ctx->event, ctx->timeout);
|
|
586 }
|
|
587
|
|
588 if (ngx_queue_empty(&r->name_resend_queue)) {
|
|
589 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000));
|
|
590 }
|
|
591
|
|
592 rn->expire = ngx_time() + r->resend_timeout;
|
|
593
|
|
594 ngx_queue_insert_head(&r->name_resend_queue, &rn->queue);
|
|
595
|
|
596 rn->cnlen = 0;
|
|
597 rn->naddrs = 0;
|
|
598 rn->valid = 0;
|
|
599 rn->waiting = ctx;
|
|
600
|
|
601 ctx->state = NGX_AGAIN;
|
|
602
|
|
603 return NGX_AGAIN;
|
|
604
|
|
605 failed:
|
|
606
|
|
607 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
608
|
372
|
609 if (rn->query) {
|
|
610 ngx_resolver_free(r, rn->query);
|
|
611 }
|
|
612
|
350
|
613 ngx_resolver_free(r, rn->name);
|
|
614
|
|
615 ngx_resolver_free(r, rn);
|
|
616
|
|
617 return NGX_ERROR;
|
|
618 }
|
|
619
|
|
620
|
|
621 ngx_int_t
|
|
622 ngx_resolve_addr(ngx_resolver_ctx_t *ctx)
|
|
623 {
|
442
|
624 u_char *name;
|
350
|
625 ngx_resolver_t *r;
|
|
626 ngx_resolver_node_t *rn;
|
|
627
|
|
628 r = ctx->resolver;
|
|
629
|
|
630 ctx->addr = ntohl(ctx->addr);
|
|
631
|
|
632 /* lock addr mutex */
|
|
633
|
|
634 rn = ngx_resolver_lookup_addr(r, ctx->addr);
|
|
635
|
|
636 if (rn) {
|
|
637
|
|
638 if (rn->valid >= ngx_time()) {
|
|
639
|
|
640 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached");
|
|
641
|
|
642 ngx_queue_remove(&rn->queue);
|
|
643
|
|
644 rn->expire = ngx_time() + r->expire;
|
|
645
|
|
646 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue);
|
|
647
|
442
|
648 name = ngx_resolver_dup(r, rn->name, rn->nlen);
|
|
649 if (name == NULL) {
|
350
|
650 goto failed;
|
|
651 }
|
|
652
|
442
|
653 ctx->name.len = rn->nlen;
|
|
654 ctx->name.data = name;
|
|
655
|
350
|
656 /* unlock addr mutex */
|
|
657
|
|
658 ctx->state = NGX_OK;
|
|
659
|
|
660 ctx->handler(ctx);
|
|
661
|
442
|
662 ngx_resolver_free(r, name);
|
350
|
663
|
|
664 return NGX_OK;
|
|
665 }
|
|
666
|
|
667 if (rn->waiting) {
|
|
668
|
|
669 ctx->next = rn->waiting;
|
|
670 rn->waiting = ctx;
|
542
|
671 ctx->state = NGX_AGAIN;
|
350
|
672
|
442
|
673 /* unlock addr mutex */
|
|
674
|
|
675 return NGX_OK;
|
350
|
676 }
|
|
677
|
|
678 ngx_queue_remove(&rn->queue);
|
|
679
|
|
680 ngx_resolver_free(r, rn->query);
|
372
|
681 rn->query = NULL;
|
350
|
682
|
|
683 } else {
|
|
684 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t));
|
|
685 if (rn == NULL) {
|
|
686 goto failed;
|
|
687 }
|
|
688
|
|
689 rn->node.key = ctx->addr;
|
372
|
690 rn->query = NULL;
|
350
|
691
|
|
692 ngx_rbtree_insert(&r->addr_rbtree, &rn->node);
|
|
693 }
|
|
694
|
|
695 if (ngx_resolver_create_addr_query(rn, ctx) != NGX_OK) {
|
|
696 goto failed;
|
|
697 }
|
|
698
|
|
699 if (ngx_resolver_send_query(r, rn) != NGX_OK) {
|
|
700 goto failed;
|
|
701 }
|
|
702
|
|
703 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t));
|
|
704 if (ctx->event == NULL) {
|
|
705 goto failed;
|
|
706 }
|
|
707
|
|
708 ctx->event->handler = ngx_resolver_timeout_handler;
|
|
709 ctx->event->data = ctx;
|
|
710 ctx->event->log = r->log;
|
|
711 ctx->ident = -1;
|
|
712
|
|
713 ngx_add_timer(ctx->event, ctx->timeout);
|
|
714
|
|
715 if (ngx_queue_empty(&r->addr_resend_queue)) {
|
|
716 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000));
|
|
717 }
|
|
718
|
|
719 rn->expire = ngx_time() + r->resend_timeout;
|
|
720
|
|
721 ngx_queue_insert_head(&r->addr_resend_queue, &rn->queue);
|
|
722
|
|
723 rn->cnlen = 0;
|
|
724 rn->naddrs = 0;
|
|
725 rn->name = NULL;
|
|
726 rn->nlen = 0;
|
|
727 rn->valid = 0;
|
|
728 rn->waiting = ctx;
|
|
729
|
|
730 /* unlock addr mutex */
|
|
731
|
|
732 ctx->state = NGX_AGAIN;
|
|
733
|
|
734 return NGX_OK;
|
|
735
|
|
736 failed:
|
|
737
|
|
738 if (rn) {
|
|
739 ngx_rbtree_delete(&r->addr_rbtree, &rn->node);
|
|
740
|
372
|
741 if (rn->query) {
|
|
742 ngx_resolver_free(r, rn->query);
|
|
743 }
|
|
744
|
350
|
745 ngx_resolver_free(r, rn);
|
|
746 }
|
|
747
|
|
748 /* unlock addr mutex */
|
|
749
|
|
750 if (ctx->event) {
|
366
|
751 ngx_resolver_free(r, ctx->event);
|
350
|
752 }
|
|
753
|
366
|
754 ngx_resolver_free(r, ctx);
|
350
|
755
|
|
756 return NGX_ERROR;
|
|
757 }
|
|
758
|
|
759
|
|
760 void
|
|
761 ngx_resolve_addr_done(ngx_resolver_ctx_t *ctx)
|
|
762 {
|
|
763 in_addr_t addr;
|
|
764 ngx_resolver_t *r;
|
|
765 ngx_resolver_ctx_t *w, **p;
|
|
766 ngx_resolver_node_t *rn;
|
|
767
|
|
768 r = ctx->resolver;
|
|
769
|
|
770 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
771 "resolve addr done: %i", ctx->state);
|
|
772
|
|
773 if (ctx->event && ctx->event->timer_set) {
|
|
774 ngx_del_timer(ctx->event);
|
|
775 }
|
|
776
|
|
777 /* lock addr mutex */
|
|
778
|
|
779 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) {
|
|
780
|
|
781 rn = ngx_resolver_lookup_addr(r, ctx->addr);
|
|
782
|
|
783 if (rn) {
|
|
784 p = &rn->waiting;
|
|
785 w = rn->waiting;
|
|
786
|
|
787 while (w) {
|
|
788 if (w == ctx) {
|
|
789 *p = w->next;
|
|
790
|
|
791 goto done;
|
|
792 }
|
|
793
|
|
794 p = &w->next;
|
|
795 w = w->next;
|
|
796 }
|
|
797 }
|
|
798
|
|
799 addr = ntohl(ctx->addr);
|
|
800
|
|
801 ngx_log_error(NGX_LOG_ALERT, r->log, 0,
|
|
802 "could not cancel %ud.%ud.%ud.%ud resolving",
|
|
803 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
804 (addr >> 8) & 0xff, addr & 0xff);
|
|
805 }
|
|
806
|
|
807 done:
|
|
808
|
|
809 ngx_resolver_expire(r, &r->addr_rbtree, &r->addr_expire_queue);
|
|
810
|
|
811 /* unlock addr mutex */
|
|
812
|
366
|
813 /* lock alloc mutex */
|
|
814
|
|
815 if (ctx->event) {
|
|
816 ngx_resolver_free_locked(r, ctx->event);
|
|
817 }
|
|
818
|
|
819 ngx_resolver_free_locked(r, ctx);
|
|
820
|
|
821 /* unlock alloc mutex */
|
350
|
822 }
|
|
823
|
|
824
|
|
825 static void
|
|
826 ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue)
|
|
827 {
|
|
828 time_t now;
|
|
829 ngx_uint_t i;
|
|
830 ngx_queue_t *q;
|
|
831 ngx_resolver_node_t *rn;
|
|
832
|
|
833 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver expire");
|
|
834
|
|
835 now = ngx_time();
|
|
836
|
|
837 for (i = 0; i < 2; i++) {
|
|
838 if (ngx_queue_empty(queue)) {
|
|
839 return;
|
|
840 }
|
|
841
|
|
842 q = ngx_queue_last(queue);
|
|
843
|
|
844 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
845
|
|
846 if (now <= rn->expire) {
|
|
847 return;
|
|
848 }
|
|
849
|
358
|
850 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
851 "resolver expire \"%*s\"", (size_t) rn->nlen, rn->name);
|
350
|
852
|
|
853 ngx_queue_remove(q);
|
|
854
|
|
855 ngx_rbtree_delete(tree, &rn->node);
|
|
856
|
|
857 ngx_resolver_free_node(r, rn);
|
|
858 }
|
|
859 }
|
|
860
|
|
861
|
|
862 static ngx_int_t
|
|
863 ngx_resolver_send_query(ngx_resolver_t *r, ngx_resolver_node_t *rn)
|
|
864 {
|
|
865 ssize_t n;
|
|
866 ngx_udp_connection_t *uc;
|
|
867
|
646
|
868 uc = r->udp_connections.elts;
|
|
869
|
|
870 uc = &uc[r->last_connection++];
|
|
871 if (r->last_connection == r->udp_connections.nelts) {
|
|
872 r->last_connection = 0;
|
|
873 }
|
350
|
874
|
|
875 if (uc->connection == NULL) {
|
664
|
876
|
|
877 uc->log = *r->log;
|
|
878 uc->log.handler = ngx_resolver_log_error;
|
|
879 uc->log.data = uc;
|
|
880 uc->log.action = "resolving";
|
|
881
|
350
|
882 if (ngx_udp_connect(uc) != NGX_OK) {
|
|
883 return NGX_ERROR;
|
|
884 }
|
|
885
|
|
886 uc->connection->data = r;
|
|
887 uc->connection->read->handler = ngx_resolver_read_response;
|
366
|
888 uc->connection->read->resolver = 1;
|
350
|
889 }
|
|
890
|
|
891 n = ngx_send(uc->connection, rn->query, rn->qlen);
|
|
892
|
|
893 if (n == -1) {
|
|
894 return NGX_ERROR;
|
|
895 }
|
|
896
|
|
897 if ((size_t) n != (size_t) rn->qlen) {
|
560
|
898 ngx_log_error(NGX_LOG_CRIT, &uc->log, 0, "send() incomplete");
|
350
|
899 return NGX_ERROR;
|
|
900 }
|
|
901
|
|
902 return NGX_OK;
|
|
903 }
|
|
904
|
|
905
|
|
906 static void
|
|
907 ngx_resolver_resend_handler(ngx_event_t *ev)
|
|
908 {
|
|
909 time_t timer, atimer, ntimer;
|
|
910 ngx_resolver_t *r;
|
|
911
|
|
912 r = ev->data;
|
|
913
|
|
914 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
915 "resolver resend handler");
|
|
916
|
|
917 /* lock name mutex */
|
|
918
|
|
919 ntimer = ngx_resolver_resend(r, &r->name_rbtree, &r->name_resend_queue);
|
|
920
|
|
921 /* unlock name mutex */
|
|
922
|
|
923 /* lock addr mutex */
|
|
924
|
|
925 atimer = ngx_resolver_resend(r, &r->addr_rbtree, &r->addr_resend_queue);
|
354
|
926
|
350
|
927 /* unlock addr mutex */
|
|
928
|
|
929 if (ntimer == 0) {
|
|
930 timer = atimer;
|
|
931
|
|
932 } else if (atimer == 0) {
|
|
933 timer = ntimer;
|
|
934
|
|
935 } else {
|
|
936 timer = (atimer < ntimer) ? atimer : ntimer;
|
|
937 }
|
|
938
|
|
939 if (timer) {
|
|
940 ngx_add_timer(r->event, (ngx_msec_t) (timer * 1000));
|
|
941 }
|
|
942 }
|
|
943
|
|
944
|
|
945 static time_t
|
|
946 ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue)
|
|
947 {
|
|
948 time_t now;
|
|
949 ngx_queue_t *q;
|
|
950 ngx_resolver_node_t *rn;
|
|
951
|
|
952 now = ngx_time();
|
|
953
|
|
954 for ( ;; ) {
|
|
955 if (ngx_queue_empty(queue)) {
|
|
956 return 0;
|
|
957 }
|
|
958
|
|
959 q = ngx_queue_last(queue);
|
|
960
|
|
961 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
962
|
|
963 if (now < rn->expire) {
|
|
964 return rn->expire - now;
|
|
965 }
|
|
966
|
358
|
967 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
968 "resolver resend \"%*s\" %p",
|
|
969 (size_t) rn->nlen, rn->name, rn->waiting);
|
350
|
970
|
|
971 ngx_queue_remove(q);
|
|
972
|
|
973 if (rn->waiting) {
|
|
974
|
|
975 if (ngx_resolver_send_query(r, rn) == NGX_OK) {
|
|
976
|
|
977 rn->expire = now + r->resend_timeout;
|
|
978
|
|
979 ngx_queue_insert_head(queue, &rn->queue);
|
|
980 }
|
364
|
981
|
|
982 continue;
|
350
|
983 }
|
|
984
|
|
985 ngx_rbtree_delete(tree, &rn->node);
|
|
986
|
|
987 ngx_resolver_free_node(r, rn);
|
|
988 }
|
|
989 }
|
|
990
|
|
991
|
|
992 static void
|
|
993 ngx_resolver_read_response(ngx_event_t *rev)
|
|
994 {
|
|
995 ssize_t n;
|
|
996 ngx_connection_t *c;
|
|
997 u_char buf[NGX_RESOLVER_UDP_SIZE];
|
|
998
|
|
999 c = rev->data;
|
|
1000
|
|
1001 do {
|
354
|
1002 n = ngx_udp_recv(c, buf, NGX_RESOLVER_UDP_SIZE);
|
|
1003
|
|
1004 if (n < 0) {
|
350
|
1005 return;
|
|
1006 }
|
|
1007
|
|
1008 ngx_resolver_process_response(c->data, buf, n);
|
|
1009
|
|
1010 } while (rev->ready);
|
|
1011 }
|
|
1012
|
|
1013
|
|
1014 static void
|
|
1015 ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf, size_t n)
|
|
1016 {
|
|
1017 char *err;
|
|
1018 size_t len;
|
416
|
1019 ngx_uint_t i, times, ident, qident, flags, code, nqs, nan,
|
|
1020 qtype, qclass;
|
|
1021 ngx_queue_t *q;
|
350
|
1022 ngx_resolver_qs_t *qs;
|
416
|
1023 ngx_resolver_node_t *rn;
|
350
|
1024 ngx_resolver_query_t *query;
|
|
1025
|
416
|
1026 if ((size_t) n < sizeof(ngx_resolver_query_t)) {
|
350
|
1027 goto short_response;
|
|
1028 }
|
|
1029
|
|
1030 query = (ngx_resolver_query_t *) buf;
|
|
1031
|
|
1032 ident = (query->ident_hi << 8) + query->ident_lo;
|
|
1033 flags = (query->flags_hi << 8) + query->flags_lo;
|
|
1034 nqs = (query->nqs_hi << 8) + query->nqs_lo;
|
|
1035 nan = (query->nan_hi << 8) + query->nan_lo;
|
|
1036
|
|
1037 ngx_log_debug6(NGX_LOG_DEBUG_CORE, r->log, 0,
|
372
|
1038 "resolver DNS response %ui fl:%04Xui %ui/%ui/%ui/%ui",
|
350
|
1039 ident, flags, nqs, nan,
|
|
1040 (query->nns_hi << 8) + query->nns_lo,
|
|
1041 (query->nar_hi << 8) + query->nar_lo);
|
|
1042
|
|
1043 if (!(flags & 0x8000)) {
|
|
1044 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1045 "invalid DNS response %ui fl:%04Xui", ident, flags);
|
350
|
1046 return;
|
|
1047 }
|
|
1048
|
|
1049 code = flags & 0x7f;
|
|
1050
|
416
|
1051 if (code == NGX_RESOLVE_FORMERR) {
|
|
1052
|
|
1053 times = 0;
|
|
1054
|
|
1055 for (q = ngx_queue_head(&r->name_resend_queue);
|
|
1056 q != ngx_queue_sentinel(&r->name_resend_queue) || times++ < 100;
|
|
1057 q = ngx_queue_next(q))
|
|
1058 {
|
|
1059 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
1060 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1061
|
|
1062 if (qident == ident) {
|
|
1063 ngx_log_error(r->log_level, r->log, 0,
|
|
1064 "DNS error (%ui: %s), query id:%ui, name:\"%*s\"",
|
|
1065 code, ngx_resolver_strerror(code), ident,
|
|
1066 rn->nlen, rn->name);
|
|
1067 return;
|
|
1068 }
|
|
1069 }
|
|
1070
|
|
1071 goto dns_error;
|
|
1072 }
|
|
1073
|
|
1074 if (code > NGX_RESOLVE_REFUSED) {
|
|
1075 goto dns_error;
|
350
|
1076 }
|
|
1077
|
|
1078 if (nqs != 1) {
|
|
1079 err = "invalid number of questions in DNS response";
|
|
1080 goto done;
|
|
1081 }
|
|
1082
|
|
1083 i = sizeof(ngx_resolver_query_t);
|
|
1084
|
|
1085 while (i < (ngx_uint_t) n) {
|
|
1086 if (buf[i] == '\0') {
|
|
1087 goto found;
|
|
1088 }
|
|
1089
|
|
1090 len = buf[i];
|
|
1091 i += 1 + len;
|
|
1092 }
|
|
1093
|
|
1094 goto short_response;
|
|
1095
|
|
1096 found:
|
|
1097
|
|
1098 if (i++ == 0) {
|
|
1099 err = "zero-length domain name in DNS response";
|
|
1100 goto done;
|
|
1101 }
|
|
1102
|
|
1103 if (i + sizeof(ngx_resolver_qs_t) + nan * (2 + sizeof(ngx_resolver_an_t))
|
|
1104 > (ngx_uint_t) n)
|
|
1105 {
|
|
1106 goto short_response;
|
|
1107 }
|
|
1108
|
|
1109 qs = (ngx_resolver_qs_t *) &buf[i];
|
|
1110
|
|
1111 qtype = (qs->type_hi << 8) + qs->type_lo;
|
|
1112 qclass = (qs->class_hi << 8) + qs->class_lo;
|
|
1113
|
|
1114 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
372
|
1115 "resolver DNS response qt:%ui cl:%ui", qtype, qclass);
|
350
|
1116
|
|
1117 if (qclass != 1) {
|
|
1118 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1119 "unknown query class %ui in DNS response", qclass);
|
350
|
1120 return;
|
|
1121 }
|
|
1122
|
|
1123 switch (qtype) {
|
|
1124
|
|
1125 case NGX_RESOLVE_A:
|
|
1126
|
|
1127 ngx_resolver_process_a(r, buf, n, ident, code, nan,
|
356
|
1128 i + sizeof(ngx_resolver_qs_t));
|
350
|
1129
|
|
1130 break;
|
|
1131
|
|
1132 case NGX_RESOLVE_PTR:
|
|
1133
|
356
|
1134 ngx_resolver_process_ptr(r, buf, n, ident, code, nan);
|
350
|
1135
|
|
1136 break;
|
|
1137
|
|
1138 default:
|
|
1139 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1140 "unknown query type %ui in DNS response", qtype);
|
350
|
1141 return;
|
|
1142 }
|
|
1143
|
|
1144 return;
|
|
1145
|
|
1146 short_response:
|
|
1147
|
|
1148 err = "short dns response";
|
|
1149
|
|
1150 done:
|
|
1151
|
|
1152 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1153
|
|
1154 return;
|
416
|
1155
|
|
1156 dns_error:
|
|
1157
|
|
1158 ngx_log_error(r->log_level, r->log, 0,
|
|
1159 "DNS error (%ui: %s), query id:%ui",
|
|
1160 code, ngx_resolver_strerror(code), ident);
|
|
1161 return;
|
350
|
1162 }
|
|
1163
|
|
1164
|
|
1165 static void
|
|
1166 ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t last,
|
|
1167 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t ans)
|
|
1168 {
|
|
1169 char *err;
|
|
1170 u_char *cname;
|
|
1171 size_t len;
|
650
|
1172 int32_t ttl;
|
350
|
1173 uint32_t hash;
|
|
1174 in_addr_t addr, *addrs;
|
|
1175 ngx_str_t name;
|
|
1176 ngx_uint_t qtype, qident, naddrs, a, i, n, start;
|
|
1177 ngx_resolver_an_t *an;
|
|
1178 ngx_resolver_ctx_t *ctx, *next;
|
|
1179 ngx_resolver_node_t *rn;
|
|
1180
|
|
1181 if (ngx_resolver_copy(r, &name, buf, &buf[12], &buf[last]) != NGX_OK) {
|
|
1182 return;
|
|
1183 }
|
|
1184
|
|
1185 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver qs:%V", &name);
|
|
1186
|
|
1187 hash = ngx_crc32_short(name.data, name.len);
|
|
1188
|
|
1189 /* lock name mutex */
|
|
1190
|
|
1191 rn = ngx_resolver_lookup_name(r, &name, hash);
|
|
1192
|
|
1193 if (rn == NULL || rn->query == NULL) {
|
|
1194 ngx_log_error(r->log_level, r->log, 0,
|
|
1195 "unexpected response for %V", &name);
|
|
1196 goto failed;
|
|
1197 }
|
|
1198
|
|
1199 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1200
|
|
1201 if (ident != qident) {
|
|
1202 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1203 "wrong ident %ui response for %V, expect %ui",
|
350
|
1204 ident, &name, qident);
|
|
1205 goto failed;
|
|
1206 }
|
|
1207
|
528
|
1208 ngx_resolver_free(r, name.data);
|
|
1209
|
356
|
1210 if (code == 0 && nan == 0) {
|
|
1211 code = 3; /* NXDOMAIN */
|
|
1212 }
|
|
1213
|
350
|
1214 if (code) {
|
|
1215 next = rn->waiting;
|
|
1216 rn->waiting = NULL;
|
|
1217
|
|
1218 ngx_queue_remove(&rn->queue);
|
|
1219
|
|
1220 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
1221
|
|
1222 ngx_resolver_free_node(r, rn);
|
|
1223
|
|
1224 /* unlock name mutex */
|
|
1225
|
|
1226 while (next) {
|
|
1227 ctx = next;
|
|
1228 ctx->state = code;
|
|
1229 next = ctx->next;
|
|
1230
|
|
1231 ctx->handler(ctx);
|
|
1232 }
|
|
1233
|
|
1234 return;
|
|
1235 }
|
|
1236
|
|
1237 i = ans;
|
|
1238 naddrs = 0;
|
|
1239 addr = 0;
|
|
1240 addrs = NULL;
|
|
1241 cname = NULL;
|
|
1242 qtype = 0;
|
650
|
1243 ttl = 0;
|
350
|
1244
|
|
1245 for (a = 0; a < nan; a++) {
|
|
1246
|
|
1247 start = i;
|
|
1248
|
|
1249 while (i < last) {
|
|
1250
|
|
1251 if (buf[i] & 0xc0) {
|
|
1252 i += 2;
|
|
1253 goto found;
|
|
1254 }
|
|
1255
|
|
1256 if (buf[i] == 0) {
|
|
1257 i++;
|
|
1258 goto test_length;
|
|
1259 }
|
|
1260
|
|
1261 i += 1 + buf[i];
|
|
1262 }
|
|
1263
|
|
1264 goto short_response;
|
|
1265
|
|
1266 test_length:
|
|
1267
|
|
1268 if (i - start < 2) {
|
|
1269 err = "invalid name in dns response";
|
|
1270 goto invalid;
|
|
1271 }
|
|
1272
|
|
1273 found:
|
|
1274
|
|
1275 if (i + sizeof(ngx_resolver_an_t) >= last) {
|
|
1276 goto short_response;
|
|
1277 }
|
|
1278
|
|
1279 an = (ngx_resolver_an_t *) &buf[i];
|
|
1280
|
|
1281 qtype = (an->type_hi << 8) + an->type_lo;
|
|
1282 len = (an->len_hi << 8) + an->len_lo;
|
650
|
1283 ttl = (an->ttl[0] << 24) + (an->ttl[1] << 16)
|
|
1284 + (an->ttl[2] << 8) + (an->ttl[3]);
|
|
1285
|
|
1286 if (ttl < 0) {
|
|
1287 ttl = 0;
|
|
1288 }
|
350
|
1289
|
|
1290 if (qtype == NGX_RESOLVE_A) {
|
|
1291
|
|
1292 i += sizeof(ngx_resolver_an_t);
|
|
1293
|
|
1294 if (i + len > last) {
|
|
1295 goto short_response;
|
|
1296 }
|
|
1297
|
|
1298 addr = htonl((buf[i] << 24) + (buf[i + 1] << 16)
|
|
1299 + (buf[i + 2] << 8) + (buf[i + 3]));
|
|
1300
|
|
1301 naddrs++;
|
|
1302
|
|
1303 i += len;
|
|
1304
|
|
1305 } else if (qtype == NGX_RESOLVE_CNAME) {
|
|
1306 cname = &buf[i] + sizeof(ngx_resolver_an_t);
|
|
1307 i += sizeof(ngx_resolver_an_t) + len;
|
372
|
1308
|
|
1309 } else if (qtype == NGX_RESOLVE_DNAME) {
|
|
1310 i += sizeof(ngx_resolver_an_t) + len;
|
|
1311
|
|
1312 } else {
|
|
1313 ngx_log_error(r->log_level, r->log, 0,
|
|
1314 "unexpected qtype %ui", qtype);
|
350
|
1315 }
|
|
1316 }
|
|
1317
|
650
|
1318 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
1319 "resolver naddrs:%ui cname:%p ttl:%d",
|
|
1320 naddrs, cname, ttl);
|
350
|
1321
|
|
1322 if (naddrs) {
|
|
1323
|
|
1324 if (naddrs == 1) {
|
|
1325 rn->u.addr = addr;
|
|
1326
|
|
1327 } else {
|
|
1328
|
|
1329 addrs = ngx_resolver_alloc(r, naddrs * sizeof(in_addr_t));
|
|
1330 if (addrs == NULL) {
|
|
1331 return;
|
|
1332 }
|
|
1333
|
|
1334 n = 0;
|
|
1335 i = ans;
|
|
1336
|
|
1337 for (a = 0; a < nan; a++) {
|
|
1338
|
|
1339 for ( ;; ) {
|
|
1340
|
|
1341 if (buf[i] & 0xc0) {
|
|
1342 i += 2;
|
|
1343 goto ok;
|
|
1344 }
|
|
1345
|
|
1346 if (buf[i] == 0) {
|
|
1347 i++;
|
|
1348 goto ok;
|
|
1349 }
|
|
1350
|
|
1351 i += 1 + buf[i];
|
|
1352 }
|
|
1353
|
|
1354 ok:
|
|
1355
|
|
1356 an = (ngx_resolver_an_t *) &buf[i];
|
|
1357
|
|
1358 qtype = (an->type_hi << 8) + an->type_lo;
|
|
1359 len = (an->len_hi << 8) + an->len_lo;
|
|
1360
|
|
1361 i += sizeof(ngx_resolver_an_t);
|
|
1362
|
|
1363 if (qtype == NGX_RESOLVE_A) {
|
|
1364
|
|
1365 addrs[n++] = htonl((buf[i] << 24) + (buf[i + 1] << 16)
|
|
1366 + (buf[i + 2] << 8) + (buf[i + 3]));
|
|
1367
|
|
1368 if (n == naddrs) {
|
|
1369 break;
|
|
1370 }
|
|
1371 }
|
|
1372
|
|
1373 i += len;
|
|
1374 }
|
|
1375
|
|
1376 rn->u.addrs = addrs;
|
|
1377
|
|
1378 addrs = ngx_resolver_dup(r, rn->u.addrs,
|
|
1379 naddrs * sizeof(in_addr_t));
|
|
1380 if (addrs == NULL) {
|
|
1381 return;
|
|
1382 }
|
|
1383 }
|
|
1384
|
|
1385 rn->naddrs = (u_short) naddrs;
|
|
1386
|
|
1387 ngx_queue_remove(&rn->queue);
|
|
1388
|
650
|
1389 rn->valid = ngx_time() + (r->valid ? r->valid : ttl);
|
350
|
1390 rn->expire = ngx_time() + r->expire;
|
|
1391
|
|
1392 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
1393
|
|
1394 next = rn->waiting;
|
|
1395 rn->waiting = NULL;
|
|
1396
|
|
1397 /* unlock name mutex */
|
|
1398
|
|
1399 while (next) {
|
|
1400 ctx = next;
|
|
1401 ctx->state = NGX_OK;
|
|
1402 ctx->naddrs = naddrs;
|
|
1403 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs;
|
|
1404 ctx->addr = addr;
|
|
1405 next = ctx->next;
|
|
1406
|
|
1407 ctx->handler(ctx);
|
|
1408 }
|
|
1409
|
442
|
1410 if (naddrs > 1) {
|
350
|
1411 ngx_resolver_free(r, addrs);
|
|
1412 }
|
|
1413
|
674
|
1414 ngx_resolver_free(r, rn->query);
|
|
1415 rn->query = NULL;
|
|
1416
|
350
|
1417 return;
|
|
1418
|
|
1419 } else if (cname) {
|
|
1420
|
|
1421 /* CNAME only */
|
|
1422
|
|
1423 if (ngx_resolver_copy(r, &name, buf, cname, &buf[last]) != NGX_OK) {
|
|
1424 return;
|
|
1425 }
|
|
1426
|
|
1427 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
1428 "resolver cname:\"%V\"", &name);
|
|
1429
|
356
|
1430 ngx_queue_remove(&rn->queue);
|
|
1431
|
350
|
1432 rn->cnlen = (u_short) name.len;
|
|
1433 rn->u.cname = name.data;
|
650
|
1434
|
|
1435 rn->valid = ngx_time() + (r->valid ? r->valid : ttl);
|
350
|
1436 rn->expire = ngx_time() + r->expire;
|
|
1437
|
|
1438 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
1439
|
|
1440 ctx = rn->waiting;
|
|
1441 rn->waiting = NULL;
|
|
1442
|
|
1443 if (ctx) {
|
|
1444 ctx->name = name;
|
|
1445
|
|
1446 (void) ngx_resolve_name_locked(r, ctx);
|
|
1447 }
|
|
1448
|
674
|
1449 ngx_resolver_free(r, rn->query);
|
|
1450 rn->query = NULL;
|
|
1451
|
350
|
1452 return;
|
|
1453 }
|
|
1454
|
|
1455 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1456 "no A or CNAME types in DNS responses, unknown query type: %ui",
|
|
1457 qtype);
|
350
|
1458 return;
|
|
1459
|
|
1460 short_response:
|
|
1461
|
|
1462 err = "short dns response";
|
|
1463
|
|
1464 invalid:
|
|
1465
|
|
1466 /* unlock name mutex */
|
|
1467
|
|
1468 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1469
|
|
1470 return;
|
|
1471
|
|
1472 failed:
|
|
1473
|
|
1474 /* unlock name mutex */
|
|
1475
|
528
|
1476 ngx_resolver_free(r, name.data);
|
|
1477
|
350
|
1478 return;
|
|
1479 }
|
|
1480
|
|
1481
|
|
1482 static void
|
|
1483 ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n,
|
356
|
1484 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan)
|
350
|
1485 {
|
|
1486 char *err;
|
|
1487 size_t len;
|
|
1488 in_addr_t addr;
|
650
|
1489 int32_t ttl;
|
350
|
1490 ngx_int_t digit;
|
|
1491 ngx_str_t name;
|
622
|
1492 ngx_uint_t i, mask, qident;
|
350
|
1493 ngx_resolver_an_t *an;
|
|
1494 ngx_resolver_ctx_t *ctx, *next;
|
|
1495 ngx_resolver_node_t *rn;
|
|
1496
|
|
1497 if (ngx_resolver_copy(r, NULL, buf, &buf[12], &buf[n]) != NGX_OK) {
|
|
1498 goto invalid_in_addr_arpa;
|
|
1499 }
|
|
1500
|
|
1501 addr = 0;
|
|
1502 i = 12;
|
|
1503
|
|
1504 for (mask = 0; mask < 32; mask += 8) {
|
|
1505 len = buf[i++];
|
|
1506
|
|
1507 digit = ngx_atoi(&buf[i], len);
|
|
1508 if (digit == NGX_ERROR || digit > 255) {
|
|
1509 goto invalid_in_addr_arpa;
|
|
1510 }
|
|
1511
|
|
1512 addr += digit << mask;
|
|
1513 i += len;
|
|
1514 }
|
|
1515
|
|
1516 if (ngx_strcmp(&buf[i], "\7in-addr\4arpa") != 0) {
|
|
1517 goto invalid_in_addr_arpa;
|
|
1518 }
|
|
1519
|
|
1520 /* lock addr mutex */
|
|
1521
|
|
1522 rn = ngx_resolver_lookup_addr(r, addr);
|
|
1523
|
|
1524 if (rn == NULL || rn->query == NULL) {
|
|
1525 ngx_log_error(r->log_level, r->log, 0,
|
|
1526 "unexpected response for %ud.%ud.%ud.%ud",
|
|
1527 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
1528 (addr >> 8) & 0xff, addr & 0xff);
|
|
1529 goto failed;
|
|
1530 }
|
|
1531
|
|
1532 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1533
|
|
1534 if (ident != qident) {
|
|
1535 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1536 "wrong ident %ui response for %ud.%ud.%ud.%ud, expect %ui",
|
|
1537 ident, (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
1538 (addr >> 8) & 0xff, addr & 0xff, qident);
|
350
|
1539 goto failed;
|
|
1540 }
|
|
1541
|
356
|
1542 if (code == 0 && nan == 0) {
|
|
1543 code = 3; /* NXDOMAIN */
|
|
1544 }
|
|
1545
|
350
|
1546 if (code) {
|
|
1547 next = rn->waiting;
|
|
1548 rn->waiting = NULL;
|
|
1549
|
|
1550 ngx_queue_remove(&rn->queue);
|
|
1551
|
|
1552 ngx_rbtree_delete(&r->addr_rbtree, &rn->node);
|
|
1553
|
|
1554 ngx_resolver_free_node(r, rn);
|
|
1555
|
|
1556 /* unlock addr mutex */
|
|
1557
|
|
1558 while (next) {
|
|
1559 ctx = next;
|
|
1560 ctx->state = code;
|
|
1561 next = ctx->next;
|
|
1562
|
|
1563 ctx->handler(ctx);
|
|
1564 }
|
|
1565
|
|
1566 return;
|
|
1567 }
|
|
1568
|
|
1569 i += sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t);
|
|
1570
|
|
1571 if (i + 2 + sizeof(ngx_resolver_an_t) > (ngx_uint_t) n) {
|
|
1572 goto short_response;
|
|
1573 }
|
|
1574
|
|
1575 /* compression pointer to "XX.XX.XX.XX.in-addr.arpa */
|
|
1576
|
|
1577 if (buf[i] != 0xc0 || buf[i + 1] != 0x0c) {
|
|
1578 err = "invalid in-addr.arpa name in DNS response";
|
|
1579 goto invalid;
|
|
1580 }
|
|
1581
|
|
1582 an = (ngx_resolver_an_t *) &buf[i + 2];
|
|
1583
|
|
1584 len = (an->len_hi << 8) + an->len_lo;
|
650
|
1585 ttl = (an->ttl[0] << 24) + (an->ttl[1] << 16)
|
|
1586 + (an->ttl[2] << 8) + (an->ttl[3]);
|
|
1587
|
|
1588 if (ttl < 0) {
|
|
1589 ttl = 0;
|
|
1590 }
|
350
|
1591
|
|
1592 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
622
|
1593 "resolver qt:%ui cl:%ui len:%uz",
|
|
1594 (an->type_hi << 8) + an->type_lo,
|
|
1595 (an->class_hi << 8) + an->class_lo, len);
|
350
|
1596
|
|
1597 i += 2 + sizeof(ngx_resolver_an_t);
|
|
1598
|
|
1599 if (i + len > (ngx_uint_t) n) {
|
|
1600 goto short_response;
|
|
1601 }
|
|
1602
|
|
1603 if (ngx_resolver_copy(r, &name, buf, &buf[i], &buf[n]) != NGX_OK) {
|
|
1604 return;
|
|
1605 }
|
|
1606
|
|
1607 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver an:%V", &name);
|
|
1608
|
442
|
1609 if (name.len != (size_t) rn->nlen
|
|
1610 || ngx_strncmp(name.data, rn->name, name.len) != 0)
|
350
|
1611 {
|
442
|
1612 if (rn->nlen) {
|
|
1613 ngx_resolver_free(r, rn->name);
|
|
1614 }
|
|
1615
|
|
1616 rn->nlen = (u_short) name.len;
|
350
|
1617 rn->name = name.data;
|
|
1618
|
442
|
1619 name.data = ngx_resolver_dup(r, rn->name, name.len);
|
350
|
1620 if (name.data == NULL) {
|
|
1621 goto failed;
|
|
1622 }
|
|
1623 }
|
|
1624
|
|
1625 ngx_queue_remove(&rn->queue);
|
|
1626
|
650
|
1627 rn->valid = ngx_time() + (r->valid ? r->valid : ttl);
|
350
|
1628 rn->expire = ngx_time() + r->expire;
|
|
1629
|
|
1630 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue);
|
|
1631
|
|
1632 next = rn->waiting;
|
|
1633 rn->waiting = NULL;
|
|
1634
|
|
1635 /* unlock addr mutex */
|
|
1636
|
|
1637 while (next) {
|
|
1638 ctx = next;
|
|
1639 ctx->state = NGX_OK;
|
|
1640 ctx->name = name;
|
|
1641 next = ctx->next;
|
|
1642
|
|
1643 ctx->handler(ctx);
|
|
1644 }
|
|
1645
|
|
1646 ngx_resolver_free(r, name.data);
|
|
1647
|
|
1648 return;
|
|
1649
|
|
1650 invalid_in_addr_arpa:
|
|
1651
|
|
1652 ngx_log_error(r->log_level, r->log, 0,
|
|
1653 "invalid in-addr.arpa name in DNS response");
|
|
1654 return;
|
|
1655
|
|
1656 short_response:
|
|
1657
|
|
1658 err = "short DNS response";
|
|
1659
|
|
1660 invalid:
|
|
1661
|
|
1662 /* unlock addr mutex */
|
|
1663
|
|
1664 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1665
|
|
1666 return;
|
|
1667
|
|
1668 failed:
|
|
1669
|
|
1670 /* unlock addr mutex */
|
|
1671
|
|
1672 return;
|
|
1673 }
|
|
1674
|
|
1675
|
|
1676 static ngx_resolver_node_t *
|
|
1677 ngx_resolver_lookup_name(ngx_resolver_t *r, ngx_str_t *name, uint32_t hash)
|
|
1678 {
|
|
1679 ngx_int_t rc;
|
|
1680 ngx_rbtree_node_t *node, *sentinel;
|
|
1681 ngx_resolver_node_t *rn;
|
|
1682
|
|
1683 node = r->name_rbtree.root;
|
|
1684 sentinel = r->name_rbtree.sentinel;
|
|
1685
|
|
1686 while (node != sentinel) {
|
|
1687
|
|
1688 if (hash < node->key) {
|
|
1689 node = node->left;
|
|
1690 continue;
|
|
1691 }
|
|
1692
|
|
1693 if (hash > node->key) {
|
|
1694 node = node->right;
|
|
1695 continue;
|
|
1696 }
|
|
1697
|
|
1698 /* hash == node->key */
|
|
1699
|
664
|
1700 rn = (ngx_resolver_node_t *) node;
|
|
1701
|
|
1702 rc = ngx_memn2cmp(name->data, rn->name, name->len, rn->nlen);
|
|
1703
|
|
1704 if (rc == 0) {
|
|
1705 return rn;
|
|
1706 }
|
|
1707
|
|
1708 node = (rc < 0) ? node->left : node->right;
|
350
|
1709 }
|
|
1710
|
|
1711 /* not found */
|
|
1712
|
|
1713 return NULL;
|
|
1714 }
|
|
1715
|
|
1716
|
|
1717 static ngx_resolver_node_t *
|
|
1718 ngx_resolver_lookup_addr(ngx_resolver_t *r, in_addr_t addr)
|
|
1719 {
|
|
1720 ngx_rbtree_node_t *node, *sentinel;
|
|
1721
|
|
1722 node = r->addr_rbtree.root;
|
|
1723 sentinel = r->addr_rbtree.sentinel;
|
|
1724
|
|
1725 while (node != sentinel) {
|
|
1726
|
|
1727 if (addr < node->key) {
|
|
1728 node = node->left;
|
|
1729 continue;
|
|
1730 }
|
|
1731
|
|
1732 if (addr > node->key) {
|
|
1733 node = node->right;
|
|
1734 continue;
|
|
1735 }
|
|
1736
|
|
1737 /* addr == node->key */
|
|
1738
|
|
1739 return (ngx_resolver_node_t *) node;
|
|
1740 }
|
|
1741
|
|
1742 /* not found */
|
|
1743
|
|
1744 return NULL;
|
|
1745 }
|
|
1746
|
|
1747
|
|
1748 static void
|
|
1749 ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp,
|
|
1750 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)
|
|
1751 {
|
|
1752 ngx_rbtree_node_t **p;
|
|
1753 ngx_resolver_node_t *rn, *rn_temp;
|
|
1754
|
|
1755 for ( ;; ) {
|
|
1756
|
|
1757 if (node->key < temp->key) {
|
|
1758
|
|
1759 p = &temp->left;
|
|
1760
|
|
1761 } else if (node->key > temp->key) {
|
|
1762
|
|
1763 p = &temp->right;
|
|
1764
|
|
1765 } else { /* node->key == temp->key */
|
|
1766
|
|
1767 rn = (ngx_resolver_node_t *) node;
|
|
1768 rn_temp = (ngx_resolver_node_t *) temp;
|
|
1769
|
528
|
1770 p = (ngx_memn2cmp(rn->name, rn_temp->name, rn->nlen, rn_temp->nlen)
|
|
1771 < 0) ? &temp->left : &temp->right;
|
350
|
1772 }
|
|
1773
|
|
1774 if (*p == sentinel) {
|
|
1775 break;
|
|
1776 }
|
|
1777
|
|
1778 temp = *p;
|
|
1779 }
|
|
1780
|
|
1781 *p = node;
|
|
1782 node->parent = temp;
|
|
1783 node->left = sentinel;
|
|
1784 node->right = sentinel;
|
|
1785 ngx_rbt_red(node);
|
|
1786 }
|
|
1787
|
|
1788
|
|
1789 static ngx_int_t
|
|
1790 ngx_resolver_create_name_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx)
|
|
1791 {
|
|
1792 u_char *p, *s;
|
544
|
1793 size_t len, nlen;
|
350
|
1794 ngx_uint_t ident;
|
|
1795 ngx_resolver_qs_t *qs;
|
|
1796 ngx_resolver_query_t *query;
|
|
1797
|
544
|
1798 nlen = ctx->name.len ? (1 + ctx->name.len + 1) : 1;
|
|
1799
|
|
1800 len = sizeof(ngx_resolver_query_t) + nlen + sizeof(ngx_resolver_qs_t);
|
|
1801
|
|
1802 p = ngx_resolver_alloc(ctx->resolver, len);
|
350
|
1803 if (p == NULL) {
|
|
1804 return NGX_ERROR;
|
|
1805 }
|
|
1806
|
|
1807 rn->qlen = (u_short) len;
|
|
1808 rn->query = p;
|
|
1809
|
|
1810 query = (ngx_resolver_query_t *) p;
|
|
1811
|
|
1812 ident = ngx_random();
|
|
1813
|
|
1814 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0,
|
|
1815 "resolve: \"%V\" %i", &ctx->name, ident & 0xffff);
|
|
1816
|
|
1817 query->ident_hi = (u_char) ((ident >> 8) & 0xff);
|
|
1818 query->ident_lo = (u_char) (ident & 0xff);
|
|
1819
|
|
1820 /* recursion query */
|
|
1821 query->flags_hi = 1; query->flags_lo = 0;
|
|
1822
|
|
1823 /* one question */
|
|
1824 query->nqs_hi = 0; query->nqs_lo = 1;
|
|
1825 query->nan_hi = 0; query->nan_lo = 0;
|
|
1826 query->nns_hi = 0; query->nns_lo = 0;
|
|
1827 query->nar_hi = 0; query->nar_lo = 0;
|
|
1828
|
544
|
1829 p += sizeof(ngx_resolver_query_t) + nlen;
|
350
|
1830
|
|
1831 qs = (ngx_resolver_qs_t *) p;
|
|
1832
|
|
1833 /* query type */
|
|
1834 qs->type_hi = 0; qs->type_lo = (u_char) ctx->type;
|
|
1835
|
|
1836 /* IP query class */
|
|
1837 qs->class_hi = 0; qs->class_lo = 1;
|
|
1838
|
|
1839 /* convert "www.example.com" to "\3www\7example\3com\0" */
|
|
1840
|
|
1841 len = 0;
|
|
1842 p--;
|
|
1843 *p-- = '\0';
|
|
1844
|
674
|
1845 if (ctx->name.len == 0) {
|
|
1846 return NGX_DECLINED;
|
|
1847 }
|
|
1848
|
350
|
1849 for (s = ctx->name.data + ctx->name.len - 1; s >= ctx->name.data; s--) {
|
|
1850 if (*s != '.') {
|
|
1851 *p = *s;
|
|
1852 len++;
|
|
1853
|
|
1854 } else {
|
668
|
1855 if (len == 0 || len > 255) {
|
372
|
1856 return NGX_DECLINED;
|
|
1857 }
|
|
1858
|
350
|
1859 *p = (u_char) len;
|
|
1860 len = 0;
|
|
1861 }
|
|
1862
|
|
1863 p--;
|
|
1864 }
|
|
1865
|
668
|
1866 if (len == 0 || len > 255) {
|
|
1867 return NGX_DECLINED;
|
|
1868 }
|
|
1869
|
350
|
1870 *p = (u_char) len;
|
|
1871
|
|
1872 return NGX_OK;
|
|
1873 }
|
|
1874
|
|
1875
|
|
1876 /* AF_INET only */
|
|
1877
|
|
1878 static ngx_int_t
|
|
1879 ngx_resolver_create_addr_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx)
|
|
1880 {
|
|
1881 u_char *p, *d;
|
|
1882 size_t len;
|
|
1883 ngx_int_t n;
|
|
1884 ngx_uint_t ident;
|
|
1885 ngx_resolver_query_t *query;
|
|
1886
|
|
1887 len = sizeof(ngx_resolver_query_t)
|
|
1888 + sizeof(".255.255.255.255.in-addr.arpa.") - 1
|
|
1889 + sizeof(ngx_resolver_qs_t);
|
|
1890
|
544
|
1891 p = ngx_resolver_alloc(ctx->resolver, len);
|
350
|
1892 if (p == NULL) {
|
|
1893 return NGX_ERROR;
|
|
1894 }
|
|
1895
|
|
1896 rn->query = p;
|
|
1897 query = (ngx_resolver_query_t *) p;
|
|
1898
|
|
1899 ident = ngx_random();
|
|
1900
|
|
1901 query->ident_hi = (u_char) ((ident >> 8) & 0xff);
|
|
1902 query->ident_lo = (u_char) (ident & 0xff);
|
|
1903
|
|
1904 /* recursion query */
|
|
1905 query->flags_hi = 1; query->flags_lo = 0;
|
|
1906
|
|
1907 /* one question */
|
|
1908 query->nqs_hi = 0; query->nqs_lo = 1;
|
|
1909 query->nan_hi = 0; query->nan_lo = 0;
|
|
1910 query->nns_hi = 0; query->nns_lo = 0;
|
|
1911 query->nar_hi = 0; query->nar_lo = 0;
|
|
1912
|
|
1913 p += sizeof(ngx_resolver_query_t);
|
|
1914
|
582
|
1915 for (n = 0; n < 32; n += 8) {
|
350
|
1916 d = ngx_sprintf(&p[1], "%ud", (ctx->addr >> n) & 0xff);
|
|
1917 *p = (u_char) (d - &p[1]);
|
|
1918 p = d;
|
|
1919 }
|
|
1920
|
|
1921 /* query type "PTR", IP query class */
|
|
1922 ngx_memcpy(p, "\7in-addr\4arpa\0\0\14\0\1", 18);
|
|
1923
|
|
1924 rn->qlen = (u_short)
|
|
1925 (p + sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t)
|
|
1926 - rn->query);
|
|
1927
|
|
1928 return NGX_OK;
|
|
1929 }
|
|
1930
|
|
1931
|
|
1932 static ngx_int_t
|
|
1933 ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name, u_char *buf, u_char *src,
|
|
1934 u_char *last)
|
|
1935 {
|
|
1936 char *err;
|
|
1937 u_char *p, *dst;
|
|
1938 ssize_t len;
|
|
1939 ngx_uint_t i, n;
|
|
1940
|
|
1941 p = src;
|
|
1942 len = -1;
|
|
1943
|
|
1944 /*
|
|
1945 * compression pointers allow to create endless loop, so we set limit;
|
|
1946 * 128 pointers should be enough to store 255-byte name
|
|
1947 */
|
|
1948
|
|
1949 for (i = 0; i < 128; i++) {
|
|
1950 n = *p++;
|
|
1951
|
|
1952 if (n == 0) {
|
|
1953 goto done;
|
|
1954 }
|
|
1955
|
|
1956 if (n & 0xc0) {
|
420
|
1957 n = ((n & 0x3f) << 8) + *p;
|
350
|
1958 p = &buf[n];
|
|
1959
|
|
1960 } else {
|
|
1961 len += 1 + n;
|
|
1962 p = &p[n];
|
|
1963 }
|
|
1964
|
|
1965 if (p >= last) {
|
|
1966 err = "name is out of response";
|
|
1967 goto invalid;
|
|
1968 }
|
|
1969 }
|
|
1970
|
|
1971 err = "compression pointers loop";
|
|
1972
|
|
1973 invalid:
|
|
1974
|
|
1975 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1976
|
|
1977 return NGX_ERROR;
|
|
1978
|
|
1979 done:
|
|
1980
|
|
1981 if (name == NULL) {
|
|
1982 return NGX_OK;
|
|
1983 }
|
|
1984
|
542
|
1985 if (len == -1) {
|
|
1986 name->len = 0;
|
|
1987 name->data = NULL;
|
|
1988 return NGX_OK;
|
|
1989 }
|
|
1990
|
350
|
1991 dst = ngx_resolver_alloc(r, len);
|
|
1992 if (dst == NULL) {
|
|
1993 return NGX_ERROR;
|
|
1994 }
|
|
1995
|
|
1996 name->data = dst;
|
|
1997
|
|
1998 n = *src++;
|
|
1999
|
|
2000 for ( ;; ) {
|
648
|
2001 if (n & 0xc0) {
|
|
2002 n = ((n & 0x3f) << 8) + *src;
|
|
2003 src = &buf[n];
|
|
2004
|
|
2005 n = *src++;
|
|
2006
|
|
2007 } else {
|
350
|
2008 ngx_memcpy(dst, src, n);
|
|
2009 dst += n;
|
|
2010 src += n;
|
|
2011
|
|
2012 n = *src++;
|
|
2013
|
|
2014 if (n != 0) {
|
|
2015 *dst++ = '.';
|
|
2016 }
|
|
2017 }
|
|
2018
|
|
2019 if (n == 0) {
|
|
2020 name->len = dst - name->data;
|
|
2021 return NGX_OK;
|
|
2022 }
|
|
2023 }
|
|
2024 }
|
|
2025
|
|
2026
|
|
2027 static void
|
|
2028 ngx_resolver_timeout_handler(ngx_event_t *ev)
|
|
2029 {
|
|
2030 ngx_resolver_ctx_t *ctx;
|
|
2031
|
|
2032 ctx = ev->data;
|
|
2033
|
|
2034 ctx->state = NGX_RESOLVE_TIMEDOUT;
|
|
2035
|
|
2036 ctx->handler(ctx);
|
|
2037 }
|
|
2038
|
|
2039
|
|
2040 static void
|
|
2041 ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn)
|
|
2042 {
|
|
2043 /* lock alloc mutex */
|
|
2044
|
|
2045 if (rn->query) {
|
|
2046 ngx_resolver_free_locked(r, rn->query);
|
|
2047 }
|
|
2048
|
|
2049 if (rn->name) {
|
|
2050 ngx_resolver_free_locked(r, rn->name);
|
|
2051 }
|
|
2052
|
|
2053 if (rn->cnlen) {
|
|
2054 ngx_resolver_free_locked(r, rn->u.cname);
|
|
2055 }
|
|
2056
|
|
2057 if (rn->naddrs > 1) {
|
|
2058 ngx_resolver_free_locked(r, rn->u.addrs);
|
|
2059 }
|
|
2060
|
|
2061 ngx_resolver_free_locked(r, rn);
|
|
2062
|
|
2063 /* unlock alloc mutex */
|
|
2064 }
|
|
2065
|
|
2066
|
|
2067 static void *
|
|
2068 ngx_resolver_alloc(ngx_resolver_t *r, size_t size)
|
|
2069 {
|
|
2070 u_char *p;
|
|
2071
|
|
2072 /* lock alloc mutex */
|
|
2073
|
|
2074 p = ngx_alloc(size, r->log);
|
|
2075
|
|
2076 /* unlock alloc mutex */
|
|
2077
|
|
2078 return p;
|
|
2079 }
|
|
2080
|
|
2081
|
366
|
2082 static void *
|
350
|
2083 ngx_resolver_calloc(ngx_resolver_t *r, size_t size)
|
|
2084 {
|
|
2085 u_char *p;
|
|
2086
|
|
2087 p = ngx_resolver_alloc(r, size);
|
|
2088
|
|
2089 if (p) {
|
|
2090 ngx_memzero(p, size);
|
|
2091 }
|
|
2092
|
|
2093 return p;
|
|
2094 }
|
|
2095
|
|
2096
|
|
2097 static void
|
|
2098 ngx_resolver_free(ngx_resolver_t *r, void *p)
|
|
2099 {
|
|
2100 /* lock alloc mutex */
|
|
2101
|
|
2102 ngx_free(p);
|
|
2103
|
|
2104 /* unlock alloc mutex */
|
|
2105 }
|
|
2106
|
|
2107
|
|
2108 static void
|
|
2109 ngx_resolver_free_locked(ngx_resolver_t *r, void *p)
|
|
2110 {
|
|
2111 ngx_free(p);
|
|
2112 }
|
|
2113
|
|
2114
|
|
2115 static void *
|
|
2116 ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size)
|
|
2117 {
|
|
2118 void *dst;
|
|
2119
|
|
2120 dst = ngx_resolver_alloc(r, size);
|
|
2121
|
|
2122 if (dst == NULL) {
|
|
2123 return dst;
|
|
2124 }
|
|
2125
|
|
2126 ngx_memcpy(dst, src, size);
|
|
2127
|
|
2128 return dst;
|
|
2129 }
|
|
2130
|
|
2131
|
|
2132 char *
|
|
2133 ngx_resolver_strerror(ngx_int_t err)
|
|
2134 {
|
|
2135 static char *errors[] = {
|
|
2136 "Format error", /* FORMERR */
|
|
2137 "Server failure", /* SERVFAIL */
|
|
2138 "Host not found", /* NXDOMAIN */
|
|
2139 "Unimplemented", /* NOTIMP */
|
|
2140 "Operation refused" /* REFUSED */
|
|
2141 };
|
|
2142
|
|
2143 if (err > 0 && err < 6) {
|
|
2144 return errors[err - 1];
|
|
2145 }
|
|
2146
|
|
2147 if (err == NGX_RESOLVE_TIMEDOUT) {
|
|
2148 return "Operation timed out";
|
|
2149 }
|
|
2150
|
|
2151 return "Unknown error";
|
|
2152 }
|
|
2153
|
|
2154
|
560
|
2155 static u_char *
|
|
2156 ngx_resolver_log_error(ngx_log_t *log, u_char *buf, size_t len)
|
|
2157 {
|
|
2158 u_char *p;
|
|
2159 ngx_udp_connection_t *uc;
|
|
2160
|
|
2161 p = buf;
|
|
2162
|
|
2163 if (log->action) {
|
|
2164 p = ngx_snprintf(buf, len, " while %s", log->action);
|
|
2165 len -= p - buf;
|
|
2166 }
|
|
2167
|
|
2168 uc = log->data;
|
|
2169
|
|
2170 if (uc) {
|
|
2171 p = ngx_snprintf(p, len, ", resolver: %V", &uc->server);
|
|
2172 }
|
|
2173
|
|
2174 return p;
|
|
2175 }
|
|
2176
|
|
2177
|
350
|
2178 ngx_int_t
|
|
2179 ngx_udp_connect(ngx_udp_connection_t *uc)
|
|
2180 {
|
|
2181 int rc;
|
|
2182 ngx_int_t event;
|
|
2183 ngx_event_t *rev, *wev;
|
|
2184 ngx_socket_t s;
|
|
2185 ngx_connection_t *c;
|
|
2186
|
|
2187 s = ngx_socket(AF_INET, SOCK_DGRAM, 0);
|
|
2188
|
560
|
2189 ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &uc->log, 0, "UDP socket %d", s);
|
350
|
2190
|
|
2191 if (s == -1) {
|
560
|
2192 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2193 ngx_socket_n " failed");
|
|
2194 return NGX_ERROR;
|
|
2195 }
|
|
2196
|
560
|
2197 c = ngx_get_connection(s, &uc->log);
|
350
|
2198
|
|
2199 if (c == NULL) {
|
|
2200 if (ngx_close_socket(s) == -1) {
|
560
|
2201 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2202 ngx_close_socket_n "failed");
|
|
2203 }
|
|
2204
|
|
2205 return NGX_ERROR;
|
|
2206 }
|
|
2207
|
|
2208 if (ngx_nonblocking(s) == -1) {
|
560
|
2209 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2210 ngx_nonblocking_n " failed");
|
|
2211
|
|
2212 ngx_free_connection(c);
|
|
2213
|
|
2214 if (ngx_close_socket(s) == -1) {
|
560
|
2215 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2216 ngx_close_socket_n " failed");
|
|
2217 }
|
|
2218
|
|
2219 return NGX_ERROR;
|
|
2220 }
|
|
2221
|
|
2222 rev = c->read;
|
|
2223 wev = c->write;
|
|
2224
|
560
|
2225 rev->log = &uc->log;
|
|
2226 wev->log = &uc->log;
|
350
|
2227
|
|
2228 uc->connection = c;
|
|
2229
|
|
2230 c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
|
|
2231
|
|
2232 #if (NGX_THREADS)
|
|
2233
|
|
2234 /* TODO: lock event when call completion handler */
|
|
2235
|
|
2236 rev->lock = &c->lock;
|
|
2237 wev->lock = &c->lock;
|
|
2238 rev->own_lock = &c->lock;
|
|
2239 wev->own_lock = &c->lock;
|
|
2240
|
|
2241 #endif
|
|
2242
|
560
|
2243 ngx_log_debug3(NGX_LOG_DEBUG_EVENT, &uc->log, 0,
|
350
|
2244 "connect to %V, fd:%d #%d", &uc->server, s, c->number);
|
|
2245
|
|
2246 rc = connect(s, uc->sockaddr, uc->socklen);
|
|
2247
|
|
2248 /* TODO: aio, iocp */
|
|
2249
|
|
2250 if (rc == -1) {
|
560
|
2251 ngx_log_error(NGX_LOG_CRIT, &uc->log, ngx_socket_errno,
|
|
2252 "connect() failed");
|
350
|
2253
|
|
2254 return NGX_ERROR;
|
|
2255 }
|
|
2256
|
|
2257 /* UDP sockets are always ready to write */
|
|
2258 wev->ready = 1;
|
|
2259
|
|
2260 if (ngx_add_event) {
|
|
2261
|
|
2262 event = (ngx_event_flags & NGX_USE_CLEAR_EVENT) ?
|
|
2263 /* kqueue, epoll */ NGX_CLEAR_EVENT:
|
|
2264 /* select, poll, /dev/poll */ NGX_LEVEL_EVENT;
|
|
2265 /* eventport event type has no meaning: oneshot only */
|
|
2266
|
|
2267 if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
|
|
2268 return NGX_ERROR;
|
|
2269 }
|
|
2270
|
|
2271 } else {
|
|
2272 /* rtsig */
|
|
2273
|
|
2274 if (ngx_add_conn(c) == NGX_ERROR) {
|
|
2275 return NGX_ERROR;
|
|
2276 }
|
|
2277 }
|
|
2278
|
|
2279 return NGX_OK;
|
|
2280 }
|