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