|
980
|
1
|
|
|
2 /*
|
|
|
3 * Copyright (C) Igor Sysoev
|
|
|
4 */
|
|
|
5
|
|
|
6
|
|
|
7 #include <ngx_config.h>
|
|
|
8 #include <ngx_core.h>
|
|
|
9 #include <ngx_http.h>
|
|
|
10
|
|
|
11
|
|
|
12 typedef struct {
|
|
|
13 u_short len;
|
|
|
14 u_short conn;
|
|
|
15 u_char data[1];
|
|
|
16 } ngx_http_limit_zone_node_t;
|
|
|
17
|
|
|
18
|
|
|
19 typedef struct {
|
|
|
20 ngx_shm_zone_t *shm_zone;
|
|
|
21 ngx_rbtree_node_t *node;
|
|
|
22 } ngx_http_limit_zone_cleanup_t;
|
|
|
23
|
|
|
24
|
|
|
25 typedef struct {
|
|
|
26 ngx_shm_zone_t *shm_zone;
|
|
|
27 ngx_int_t index;
|
|
|
28 ngx_uint_t conn;
|
|
|
29 } ngx_http_limit_zone_conf_t;
|
|
|
30
|
|
|
31
|
|
|
32 static void ngx_http_limit_zone_cleanup(void *data);
|
|
|
33
|
|
|
34 static void *ngx_http_limit_zone_create_conf(ngx_conf_t *cf);
|
|
|
35 static char *ngx_http_limit_zone_merge_conf(ngx_conf_t *cf, void *parent,
|
|
|
36 void *child);
|
|
|
37 static char *ngx_http_limit_zone(ngx_conf_t *cf, ngx_command_t *cmd,
|
|
|
38 void *conf);
|
|
|
39 static char *ngx_http_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd,
|
|
|
40 void *conf);
|
|
|
41 static ngx_int_t ngx_http_limit_zone_init(ngx_conf_t *cf);
|
|
|
42
|
|
|
43
|
|
|
44 static ngx_command_t ngx_http_limit_zone_commands[] = {
|
|
|
45
|
|
|
46 { ngx_string("limit_zone"),
|
|
|
47 NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE2,
|
|
|
48 ngx_http_limit_zone,
|
|
|
49 0,
|
|
|
50 0,
|
|
|
51 NULL },
|
|
|
52
|
|
|
53 { ngx_string("limit_conn"),
|
|
|
54 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE3,
|
|
|
55 ngx_http_limit_conn,
|
|
|
56 NGX_HTTP_LOC_CONF_OFFSET,
|
|
|
57 0,
|
|
|
58 NULL },
|
|
|
59
|
|
|
60 ngx_null_command
|
|
|
61 };
|
|
|
62
|
|
|
63
|
|
|
64 static ngx_http_module_t ngx_http_limit_zone_module_ctx = {
|
|
|
65 NULL, /* preconfiguration */
|
|
|
66 ngx_http_limit_zone_init, /* postconfiguration */
|
|
|
67
|
|
|
68 NULL, /* create main configuration */
|
|
|
69 NULL, /* init main configuration */
|
|
|
70
|
|
|
71 NULL, /* create server configuration */
|
|
|
72 NULL, /* merge server configuration */
|
|
|
73
|
|
|
74 ngx_http_limit_zone_create_conf, /* create location configration */
|
|
|
75 ngx_http_limit_zone_merge_conf /* merge location configration */
|
|
|
76 };
|
|
|
77
|
|
|
78
|
|
|
79 ngx_module_t ngx_http_limit_zone_module = {
|
|
|
80 NGX_MODULE_V1,
|
|
|
81 &ngx_http_limit_zone_module_ctx, /* module context */
|
|
|
82 ngx_http_limit_zone_commands, /* module directives */
|
|
|
83 NGX_HTTP_MODULE, /* module type */
|
|
|
84 NULL, /* init master */
|
|
|
85 NULL, /* init module */
|
|
|
86 NULL, /* init process */
|
|
|
87 NULL, /* init thread */
|
|
|
88 NULL, /* exit thread */
|
|
|
89 NULL, /* exit process */
|
|
|
90 NULL, /* exit master */
|
|
|
91 NGX_MODULE_V1_PADDING
|
|
|
92 };
|
|
|
93
|
|
|
94
|
|
|
95 static ngx_int_t
|
|
|
96 ngx_http_limit_zone_handler(ngx_http_request_t *r)
|
|
|
97 {
|
|
|
98 size_t len, n;
|
|
|
99 uint32_t hash;
|
|
|
100 ngx_rbtree_t *rbtree;
|
|
|
101 ngx_slab_pool_t *shpool;
|
|
|
102 ngx_rbtree_node_t *node, *sentinel;
|
|
|
103 ngx_pool_cleanup_t *cln;
|
|
|
104 ngx_http_variable_value_t *vv;
|
|
|
105 ngx_http_limit_zone_node_t *lz;
|
|
|
106 ngx_http_limit_zone_conf_t *lzcf;
|
|
|
107 ngx_http_limit_zone_cleanup_t *lzcln;
|
|
|
108
|
|
|
109 lzcf = ngx_http_get_module_loc_conf(r, ngx_http_limit_zone_module);
|
|
|
110
|
|
|
111 if (lzcf->shm_zone == NULL) {
|
|
|
112 return NGX_DECLINED;
|
|
|
113 }
|
|
|
114
|
|
|
115 vv = ngx_http_get_indexed_variable(r, lzcf->index);
|
|
|
116
|
|
|
117 if (vv == NULL || vv->not_found) {
|
|
|
118 return NGX_DECLINED;
|
|
|
119 }
|
|
|
120
|
|
|
121 len = vv->len;
|
|
|
122
|
|
|
123 hash = ngx_crc32_short(vv->data, len);
|
|
|
124
|
|
|
125 cln = ngx_pool_cleanup_add(r->pool, sizeof(ngx_http_limit_zone_cleanup_t));
|
|
|
126 if (cln == NULL) {
|
|
|
127 return NGX_HTTP_INTERNAL_SERVER_ERROR;
|
|
|
128 }
|
|
|
129
|
|
|
130 rbtree = lzcf->shm_zone->data;
|
|
|
131 shpool = (ngx_slab_pool_t *) lzcf->shm_zone->shm.addr;
|
|
|
132
|
|
|
133 ngx_shmtx_lock(&shpool->mutex);
|
|
|
134
|
|
|
135 node = rbtree->root;
|
|
|
136 sentinel = rbtree->sentinel;
|
|
|
137
|
|
|
138 while (node != sentinel) {
|
|
|
139
|
|
|
140 if (hash < node->key) {
|
|
|
141 node = node->left;
|
|
|
142 continue;
|
|
|
143 }
|
|
|
144
|
|
|
145 if (hash > node->key) {
|
|
|
146 node = node->right;
|
|
|
147 continue;
|
|
|
148 }
|
|
|
149
|
|
|
150 if (hash == node->key ){
|
|
|
151 lz = (ngx_http_limit_zone_node_t *) &node->data;
|
|
|
152
|
|
|
153 if (len == (size_t) lz->len
|
|
|
154 && ngx_strncmp(lz->data, vv->data, len) == 0)
|
|
|
155 {
|
|
|
156 if (lz->conn < (u_short) lzcf->conn) {
|
|
|
157 lz->conn++;
|
|
|
158 goto done;
|
|
|
159 }
|
|
|
160
|
|
|
161 ngx_shmtx_unlock(&shpool->mutex);
|
|
|
162
|
|
|
163 return NGX_HTTP_SERVICE_UNAVAILABLE;
|
|
|
164 }
|
|
|
165 }
|
|
|
166 }
|
|
|
167
|
|
|
168 n = offsetof(ngx_rbtree_node_t, data)
|
|
|
169 + offsetof(ngx_http_limit_zone_node_t, data)
|
|
|
170 + len;
|
|
|
171
|
|
|
172 node = ngx_slab_alloc_locked(shpool, n);
|
|
|
173 if (node == NULL) {
|
|
|
174 ngx_shmtx_unlock(&shpool->mutex);
|
|
|
175 return NGX_HTTP_SERVICE_UNAVAILABLE;
|
|
|
176 }
|
|
|
177
|
|
|
178 lz = (ngx_http_limit_zone_node_t *) &node->data;
|
|
|
179
|
|
|
180 node->key = hash;
|
|
|
181 lz->len = (u_short) len;
|
|
|
182 lz->conn = 1;
|
|
|
183 ngx_memcpy(lz->data, vv->data, len);
|
|
|
184
|
|
|
185 ngx_rbtree_insert(rbtree, node);
|
|
|
186
|
|
|
187 done:
|
|
|
188
|
|
|
189 ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
|
|
|
190 "limit zone: %08XD %d", node->key, lz->conn);
|
|
|
191
|
|
|
192 ngx_shmtx_unlock(&shpool->mutex);
|
|
|
193
|
|
|
194 cln->handler = ngx_http_limit_zone_cleanup;
|
|
|
195 lzcln = cln->data;
|
|
|
196
|
|
|
197 lzcln->shm_zone = lzcf->shm_zone;
|
|
|
198 lzcln->node = node;
|
|
|
199
|
|
|
200 return NGX_DECLINED;
|
|
|
201 }
|
|
|
202
|
|
|
203
|
|
|
204 static void
|
|
|
205 ngx_http_limit_zone_cleanup(void *data)
|
|
|
206 {
|
|
|
207 ngx_http_limit_zone_cleanup_t *lzcln = data;
|
|
|
208
|
|
|
209 ngx_rbtree_t *rbtree;
|
|
|
210 ngx_slab_pool_t *shpool;
|
|
|
211 ngx_rbtree_node_t *node;
|
|
|
212 ngx_http_limit_zone_node_t *lz;
|
|
|
213
|
|
|
214 rbtree = lzcln->shm_zone->data;
|
|
|
215 shpool = (ngx_slab_pool_t *) lzcln->shm_zone->shm.addr;
|
|
|
216 node = lzcln->node;
|
|
|
217 lz = (ngx_http_limit_zone_node_t *) &node->data;
|
|
|
218
|
|
|
219 ngx_shmtx_lock(&shpool->mutex);
|
|
|
220
|
|
|
221 ngx_log_debug2(NGX_LOG_DEBUG_HTTP, lzcln->shm_zone->shm.log, 0,
|
|
|
222 "limit zone cleanup: %08XD %d", node->key, lz->conn);
|
|
|
223
|
|
|
224 lz->conn--;
|
|
|
225
|
|
|
226 if (lz->conn == 0) {
|
|
|
227 ngx_rbtree_delete(rbtree, node);
|
|
|
228 ngx_slab_free_locked(shpool, node);
|
|
|
229 }
|
|
|
230
|
|
|
231 ngx_shmtx_unlock(&shpool->mutex);
|
|
|
232 }
|
|
|
233
|
|
|
234
|
|
|
235 static ngx_int_t
|
|
|
236 ngx_http_limit_zone_init_zone(ngx_shm_zone_t *shm_zone)
|
|
|
237 {
|
|
|
238 ngx_rbtree_t *rbtree;
|
|
|
239 ngx_slab_pool_t *shpool;
|
|
|
240 ngx_rbtree_node_t *sentinel;
|
|
|
241
|
|
|
242 shpool = (ngx_slab_pool_t *) shm_zone->shm.addr;
|
|
|
243
|
|
|
244 rbtree = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_t));
|
|
|
245 if (rbtree == NULL) {
|
|
|
246 return NGX_ERROR;
|
|
|
247 }
|
|
|
248
|
|
|
249 sentinel = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_node_t));
|
|
|
250 if (sentinel == NULL) {
|
|
|
251 return NGX_ERROR;
|
|
|
252 }
|
|
|
253
|
|
|
254 ngx_rbtree_sentinel_init(sentinel);
|
|
|
255
|
|
|
256 rbtree->root = sentinel;
|
|
|
257 rbtree->sentinel = sentinel;
|
|
|
258 rbtree->insert = ngx_rbtree_insert_value;
|
|
|
259
|
|
|
260 shm_zone->data = rbtree;
|
|
|
261
|
|
|
262 return NGX_OK;
|
|
|
263 }
|
|
|
264
|
|
|
265
|
|
|
266 static void *
|
|
|
267 ngx_http_limit_zone_create_conf(ngx_conf_t *cf)
|
|
|
268 {
|
|
|
269 ngx_http_limit_zone_conf_t *conf;
|
|
|
270
|
|
|
271 conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_limit_zone_conf_t));
|
|
|
272 if (conf == NULL) {
|
|
|
273 return NGX_CONF_ERROR;
|
|
|
274 }
|
|
|
275
|
|
|
276 /*
|
|
|
277 * set by ngx_pcalloc():
|
|
|
278 *
|
|
|
279 * conf->shm_zone = NULL;
|
|
|
280 * conf->index = 0;
|
|
|
281 * conf->conn = 0;
|
|
|
282 */
|
|
|
283
|
|
|
284 return conf;
|
|
|
285 }
|
|
|
286
|
|
|
287
|
|
|
288 static char *
|
|
|
289 ngx_http_limit_zone_merge_conf(ngx_conf_t *cf, void *parent, void *child)
|
|
|
290 {
|
|
|
291 ngx_http_limit_zone_conf_t *prev = parent;
|
|
|
292 ngx_http_limit_zone_conf_t *conf = child;
|
|
|
293
|
|
|
294 if (conf->shm_zone == NULL) {
|
|
|
295 *conf = *prev;
|
|
|
296 }
|
|
|
297
|
|
|
298 return NGX_CONF_OK;
|
|
|
299 }
|
|
|
300
|
|
|
301
|
|
|
302 static char *
|
|
|
303 ngx_http_limit_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
|
|
|
304 {
|
|
|
305 ssize_t n;
|
|
|
306 ngx_str_t *value;
|
|
|
307 ngx_shm_zone_t *shm_zone;
|
|
|
308
|
|
|
309 value = cf->args->elts;
|
|
|
310
|
|
|
311 n = ngx_parse_size(&value[2]);
|
|
|
312
|
|
|
313 if (n == NGX_ERROR) {
|
|
|
314 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
|
315 "invalid size of limit_zone \"%V\"", &value[2]);
|
|
|
316 return NGX_CONF_ERROR;
|
|
|
317 }
|
|
|
318
|
|
|
319 if (n < (ngx_int_t) (8 * ngx_pagesize)) {
|
|
|
320 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
|
321 "limit_zone \"%V\" is too small", &value[1]);
|
|
|
322 return NGX_CONF_ERROR;
|
|
|
323 }
|
|
|
324
|
|
|
325
|
|
|
326 shm_zone = ngx_shared_memory_add(cf, &value[1], n,
|
|
|
327 &ngx_http_limit_zone_module);
|
|
|
328 if (shm_zone == NULL) {
|
|
|
329 return NGX_CONF_ERROR;
|
|
|
330 }
|
|
|
331
|
|
|
332 shm_zone->init = ngx_http_limit_zone_init_zone;
|
|
|
333
|
|
|
334 return NGX_CONF_OK;
|
|
|
335 }
|
|
|
336
|
|
|
337
|
|
|
338 static char *
|
|
|
339 ngx_http_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
|
|
|
340 {
|
|
|
341 ngx_http_limit_zone_conf_t *lzcf = conf;
|
|
|
342
|
|
|
343 ngx_int_t n;
|
|
|
344 ngx_str_t *value;
|
|
|
345
|
|
|
346 value = cf->args->elts;
|
|
|
347
|
|
|
348 n = ngx_atoi(value[1].data, value[1].len);
|
|
|
349 if (n <= 0) {
|
|
|
350 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
|
351 "invalid number of connections");
|
|
|
352 return NGX_CONF_ERROR;
|
|
|
353 }
|
|
|
354
|
|
|
355 if (value[2].data[0] != '$') {
|
|
|
356 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
|
357 "invalid variable name \"%V\"", &value[2]);
|
|
|
358 return NGX_CONF_ERROR;
|
|
|
359 }
|
|
|
360
|
|
|
361 value[2].len--;
|
|
|
362 value[2].data++;
|
|
|
363
|
|
|
364 lzcf->index = ngx_http_get_variable_index(cf, &value[2]);
|
|
|
365 if (lzcf->index == NGX_ERROR) {
|
|
|
366 return NGX_CONF_ERROR;
|
|
|
367 }
|
|
|
368
|
|
|
369 lzcf->shm_zone = ngx_shared_memory_add(cf, &value[3], 0,
|
|
|
370 &ngx_http_limit_zone_module);
|
|
|
371 if (lzcf->shm_zone == NULL) {
|
|
|
372 return NGX_CONF_ERROR;
|
|
|
373 }
|
|
|
374
|
|
|
375 lzcf->conn = n;
|
|
|
376
|
|
|
377 return NGX_CONF_OK;
|
|
|
378 }
|
|
|
379
|
|
|
380
|
|
|
381 static ngx_int_t
|
|
|
382 ngx_http_limit_zone_init(ngx_conf_t *cf)
|
|
|
383 {
|
|
|
384 ngx_http_handler_pt *h;
|
|
|
385 ngx_http_core_main_conf_t *cmcf;
|
|
|
386
|
|
|
387 cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);
|
|
|
388
|
|
|
389 h = ngx_array_push(&cmcf->phases[NGX_HTTP_PREACCESS_PHASE].handlers);
|
|
|
390 if (h == NULL) {
|
|
|
391 return NGX_ERROR;
|
|
|
392 }
|
|
|
393
|
|
|
394 *h = ngx_http_limit_zone_handler;
|
|
|
395
|
|
|
396 return NGX_OK;
|
|
|
397 }
|
