126
|
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
|
144
|
12 #define NGX_HTTP_REFERER_NO_URI_PART ((void *) 4)
|
|
13
|
126
|
14 typedef struct {
|
142
|
15 ngx_hash_t hash;
|
|
16 ngx_hash_wildcard_t *dns_wildcards;
|
126
|
17
|
142
|
18 ngx_flag_t no_referer;
|
|
19 ngx_flag_t blocked_referer;
|
126
|
20
|
142
|
21 ngx_hash_keys_arrays_t *keys;
|
126
|
22 } ngx_http_referer_conf_t;
|
|
23
|
|
24
|
|
25 static void * ngx_http_referer_create_conf(ngx_conf_t *cf);
|
|
26 static char * ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent,
|
|
27 void *child);
|
|
28 static char *ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd,
|
|
29 void *conf);
|
142
|
30 static char *ngx_http_add_referer(ngx_conf_t *cf, ngx_hash_keys_arrays_t *keys,
|
144
|
31 ngx_str_t *value, ngx_str_t *uri);
|
142
|
32 static int ngx_libc_cdecl ngx_http_cmp_referer_wildcards(const void *one,
|
|
33 const void *two);
|
126
|
34
|
|
35
|
|
36 static ngx_command_t ngx_http_referer_commands[] = {
|
|
37
|
|
38 { ngx_string("valid_referers"),
|
|
39 NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
|
|
40 ngx_http_valid_referers,
|
|
41 NGX_HTTP_LOC_CONF_OFFSET,
|
|
42 0,
|
|
43 NULL },
|
|
44
|
|
45 ngx_null_command
|
|
46 };
|
|
47
|
|
48
|
|
49 static ngx_http_module_t ngx_http_referer_module_ctx = {
|
|
50 NULL, /* preconfiguration */
|
|
51 NULL, /* postconfiguration */
|
|
52
|
|
53 NULL, /* create main configuration */
|
|
54 NULL, /* init main configuration */
|
|
55
|
|
56 NULL, /* create server configuration */
|
|
57 NULL, /* merge server configuration */
|
|
58
|
|
59 ngx_http_referer_create_conf, /* create location configuration */
|
|
60 ngx_http_referer_merge_conf /* merge location configuration */
|
|
61 };
|
|
62
|
|
63
|
|
64 ngx_module_t ngx_http_referer_module = {
|
|
65 NGX_MODULE_V1,
|
|
66 &ngx_http_referer_module_ctx, /* module context */
|
|
67 ngx_http_referer_commands, /* module directives */
|
|
68 NGX_HTTP_MODULE, /* module type */
|
|
69 NULL, /* init master */
|
|
70 NULL, /* init module */
|
|
71 NULL, /* init process */
|
|
72 NULL, /* init thread */
|
|
73 NULL, /* exit thread */
|
|
74 NULL, /* exit process */
|
|
75 NULL, /* exit master */
|
|
76 NGX_MODULE_V1_PADDING
|
|
77 };
|
|
78
|
|
79
|
|
80 static ngx_int_t
|
|
81 ngx_http_referer_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
|
|
82 uintptr_t data)
|
|
83 {
|
144
|
84 u_char *p, *ref, *last;
|
142
|
85 size_t len;
|
144
|
86 ngx_str_t *uri;
|
|
87 ngx_uint_t i, key;
|
142
|
88 ngx_http_referer_conf_t *rlcf;
|
144
|
89 u_char buf[256];
|
126
|
90
|
142
|
91 rlcf = ngx_http_get_module_loc_conf(r, ngx_http_referer_module);
|
126
|
92
|
150
|
93 if (rlcf->hash.buckets == NULL && rlcf->dns_wildcards == NULL) {
|
144
|
94 goto valid;
|
126
|
95 }
|
|
96
|
|
97 if (r->headers_in.referer == NULL) {
|
142
|
98 if (rlcf->no_referer) {
|
144
|
99 goto valid;
|
|
100 }
|
126
|
101
|
144
|
102 goto invalid;
|
126
|
103 }
|
|
104
|
|
105 len = r->headers_in.referer->value.len;
|
|
106 ref = r->headers_in.referer->value.data;
|
|
107
|
|
108 if (len < sizeof("http://i.ru") - 1
|
|
109 || (ngx_strncasecmp(ref, "http://", 7) != 0))
|
|
110 {
|
142
|
111 if (rlcf->blocked_referer) {
|
144
|
112 goto valid;
|
|
113 }
|
126
|
114
|
144
|
115 goto invalid;
|
126
|
116 }
|
|
117
|
144
|
118 last = ref + len;
|
126
|
119 ref += 7;
|
144
|
120 i = 0;
|
|
121 key = 0;
|
126
|
122
|
144
|
123 for (p = ref; p < last; p++) {
|
142
|
124 if (*p == '/' || *p == ':') {
|
|
125 break;
|
126
|
126 }
|
144
|
127
|
|
128 buf[i] = ngx_tolower(*p);
|
|
129 key = ngx_hash(key, buf[i++]);
|
|
130
|
|
131 if (i == 256) {
|
|
132 goto invalid;
|
|
133 }
|
142
|
134 }
|
126
|
135
|
142
|
136 len = p - ref;
|
126
|
137
|
142
|
138 if (rlcf->hash.buckets) {
|
144
|
139 uri = ngx_hash_find(&rlcf->hash, key, buf, len);
|
|
140 if (uri) {
|
|
141 goto uri;
|
142
|
142 }
|
|
143 }
|
126
|
144
|
150
|
145 if (rlcf->dns_wildcards) {
|
144
|
146 uri = ngx_hash_find_wildcard(rlcf->dns_wildcards, buf, len);
|
|
147 if (uri) {
|
|
148 goto uri;
|
126
|
149 }
|
|
150 }
|
|
151
|
144
|
152 invalid:
|
|
153
|
126
|
154 *v = ngx_http_variable_true_value;
|
|
155
|
|
156 return NGX_OK;
|
144
|
157
|
|
158 uri:
|
|
159
|
|
160 for ( /* void */ ; p < last; p++) {
|
|
161 if (*p == '/') {
|
|
162 break;
|
|
163 }
|
|
164 }
|
|
165
|
|
166 len = last - p;
|
|
167
|
|
168 if (uri == NGX_HTTP_REFERER_NO_URI_PART) {
|
|
169 goto valid;
|
|
170 }
|
|
171
|
|
172 if (len < uri->len || ngx_strncmp(uri->data, p, uri->len) != 0) {
|
|
173 goto invalid;
|
|
174 }
|
|
175
|
|
176 valid:
|
|
177
|
|
178 *v = ngx_http_variable_null_value;
|
|
179
|
|
180 return NGX_OK;
|
126
|
181 }
|
|
182
|
|
183
|
|
184 static void *
|
|
185 ngx_http_referer_create_conf(ngx_conf_t *cf)
|
|
186 {
|
|
187 ngx_http_referer_conf_t *conf;
|
|
188
|
142
|
189 conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_referer_conf_t));
|
126
|
190 if (conf == NULL) {
|
|
191 return NGX_CONF_ERROR;
|
|
192 }
|
|
193
|
|
194 conf->no_referer = NGX_CONF_UNSET;
|
|
195 conf->blocked_referer = NGX_CONF_UNSET;
|
|
196
|
|
197 return conf;
|
|
198 }
|
|
199
|
|
200
|
|
201 static char *
|
|
202 ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent, void *child)
|
|
203 {
|
|
204 ngx_http_referer_conf_t *prev = parent;
|
|
205 ngx_http_referer_conf_t *conf = child;
|
|
206
|
142
|
207 ngx_hash_init_t hash;
|
|
208
|
|
209 if (conf->keys == NULL) {
|
|
210 conf->hash = prev->hash;
|
|
211 conf->dns_wildcards = prev->dns_wildcards;
|
|
212
|
126
|
213 ngx_conf_merge_value(conf->no_referer, prev->no_referer, 0);
|
|
214 ngx_conf_merge_value(conf->blocked_referer, prev->blocked_referer, 0);
|
142
|
215
|
|
216 return NGX_CONF_OK;
|
|
217 }
|
|
218
|
152
|
219 if ((conf->no_referer == 1 || conf->blocked_referer == 1)
|
180
|
220 && conf->keys->keys.nelts == 0 && conf->keys->dns_wildcards.nelts == 0)
|
152
|
221 {
|
|
222 ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
|
|
223 "the \"none\" or \"blocked\" referers are specified "
|
|
224 "in the \"valid_referers\" directive "
|
|
225 "without any valid referer");
|
|
226 return NGX_CONF_ERROR;
|
|
227 }
|
|
228
|
142
|
229 hash.key = ngx_hash_key_lc;
|
|
230 hash.max_size = 2048; /* TODO: referer_hash_max_size; */
|
|
231 hash.bucket_size = 64; /* TODO: referer_hash_bucket_size; */
|
|
232 hash.name = "referers_hash";
|
|
233 hash.pool = cf->pool;
|
|
234
|
|
235 if (conf->keys->keys.nelts) {
|
|
236 hash.hash = &conf->hash;
|
|
237 hash.temp_pool = NULL;
|
|
238
|
|
239 if (ngx_hash_init(&hash, conf->keys->keys.elts, conf->keys->keys.nelts)
|
|
240 != NGX_OK)
|
|
241 {
|
|
242 return NGX_CONF_ERROR;
|
|
243 }
|
|
244 }
|
|
245
|
|
246 if (conf->keys->dns_wildcards.nelts) {
|
|
247
|
|
248 ngx_qsort(conf->keys->dns_wildcards.elts,
|
|
249 (size_t) conf->keys->dns_wildcards.nelts,
|
|
250 sizeof(ngx_hash_key_t),
|
|
251 ngx_http_cmp_referer_wildcards);
|
|
252
|
|
253 hash.hash = NULL;
|
|
254 hash.temp_pool = cf->temp_pool;
|
|
255
|
|
256 if (ngx_hash_wildcard_init(&hash, conf->keys->dns_wildcards.elts,
|
|
257 conf->keys->dns_wildcards.nelts)
|
|
258 != NGX_OK)
|
|
259 {
|
|
260 return NGX_CONF_ERROR;
|
|
261 }
|
|
262
|
|
263 conf->dns_wildcards = (ngx_hash_wildcard_t *) hash.hash;
|
126
|
264 }
|
|
265
|
|
266 if (conf->no_referer == NGX_CONF_UNSET) {
|
|
267 conf->no_referer = 0;
|
|
268 }
|
|
269
|
|
270 if (conf->blocked_referer == NGX_CONF_UNSET) {
|
|
271 conf->blocked_referer = 0;
|
|
272 }
|
|
273
|
160
|
274 conf->keys = NULL;
|
|
275
|
126
|
276 return NGX_CONF_OK;
|
|
277 }
|
|
278
|
|
279
|
|
280 static char *
|
|
281 ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
|
|
282 {
|
142
|
283 ngx_http_referer_conf_t *rlcf = conf;
|
126
|
284
|
142
|
285 u_char *p;
|
144
|
286 ngx_str_t *value, uri, name;
|
142
|
287 ngx_uint_t i, n;
|
126
|
288 ngx_http_variable_t *var;
|
|
289 ngx_http_server_name_t *sn;
|
|
290 ngx_http_core_srv_conf_t *cscf;
|
|
291
|
|
292 name.len = sizeof("invalid_referer") - 1;
|
|
293 name.data = (u_char *) "invalid_referer";
|
|
294
|
132
|
295 var = ngx_http_add_variable(cf, &name,
|
|
296 NGX_HTTP_VAR_CHANGABLE|NGX_HTTP_VAR_NOHASH);
|
126
|
297 if (var == NULL) {
|
|
298 return NGX_CONF_ERROR;
|
|
299 }
|
|
300
|
186
|
301 var->get_handler = ngx_http_referer_variable;
|
126
|
302
|
142
|
303 if (rlcf->keys == NULL) {
|
|
304 rlcf->keys = ngx_pcalloc(cf->temp_pool, sizeof(ngx_hash_keys_arrays_t));
|
|
305 if (rlcf->keys == NULL) {
|
|
306 return NGX_CONF_ERROR;
|
|
307 }
|
126
|
308
|
142
|
309 rlcf->keys->pool = cf->pool;
|
|
310 rlcf->keys->temp_pool = cf->pool;
|
|
311
|
|
312 if (ngx_hash_keys_array_init(rlcf->keys, NGX_HASH_SMALL) != NGX_OK) {
|
126
|
313 return NGX_CONF_ERROR;
|
|
314 }
|
|
315 }
|
|
316
|
|
317 value = cf->args->elts;
|
|
318
|
|
319 for (i = 1; i < cf->args->nelts; i++) {
|
|
320 if (value[i].len == 0) {
|
|
321 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
322 "invalid referer \"%V\"", &value[i]);
|
|
323 return NGX_CONF_ERROR;
|
|
324 }
|
|
325
|
|
326 if (ngx_strcmp(value[i].data, "none") == 0) {
|
142
|
327 rlcf->no_referer = 1;
|
126
|
328 continue;
|
|
329 }
|
|
330
|
|
331 if (ngx_strcmp(value[i].data, "blocked") == 0) {
|
142
|
332 rlcf->blocked_referer = 1;
|
126
|
333 continue;
|
|
334 }
|
|
335
|
144
|
336 uri.len = 0;
|
162
|
337 uri.data = NULL;
|
144
|
338
|
126
|
339 if (ngx_strcmp(value[i].data, "server_names") == 0) {
|
142
|
340
|
|
341 cscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_core_module);
|
126
|
342
|
142
|
343 sn = cscf->server_names.elts;
|
|
344 for (n = 0; n < cscf->server_names.nelts; n++) {
|
144
|
345 if (ngx_http_add_referer(cf, rlcf->keys, &sn[n].name, &uri)
|
|
346 != NGX_OK)
|
|
347 {
|
142
|
348 return NGX_CONF_ERROR;
|
|
349 }
|
|
350 }
|
126
|
351
|
|
352 continue;
|
|
353 }
|
|
354
|
142
|
355 p = (u_char *) ngx_strstr(value[i].data, "/");
|
126
|
356
|
142
|
357 if (p) {
|
144
|
358 uri.len = (value[i].data + value[i].len) - p;
|
|
359 uri.data = p;
|
142
|
360 value[i].len = p - value[i].data;
|
126
|
361 }
|
|
362
|
144
|
363 if (ngx_http_add_referer(cf, rlcf->keys, &value[i], &uri) != NGX_OK) {
|
126
|
364 return NGX_CONF_ERROR;
|
|
365 }
|
|
366 }
|
|
367
|
|
368 return NGX_CONF_OK;
|
|
369 }
|
142
|
370
|
|
371
|
|
372 static char *
|
|
373 ngx_http_add_referer(ngx_conf_t *cf, ngx_hash_keys_arrays_t *keys,
|
144
|
374 ngx_str_t *value, ngx_str_t *uri)
|
142
|
375 {
|
144
|
376 u_char ch;
|
|
377 ngx_int_t rc;
|
|
378 ngx_str_t *u;
|
|
379 ngx_uint_t flags;
|
142
|
380
|
|
381 ch = value->data[0];
|
|
382
|
|
383 if ((ch == '*' && (value->len < 3 || value->data[1] != '.'))
|
|
384 || (ch == '.' && value->len < 2))
|
|
385 {
|
|
386 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
387 "invalid DNS wildcard \"%V\"", value);
|
|
388
|
|
389 return NGX_CONF_ERROR;
|
|
390 }
|
|
391
|
|
392 flags = (ch == '*' || ch == '.') ? NGX_HASH_WILDCARD_KEY : 0;
|
|
393
|
144
|
394 if (uri->len == 0) {
|
|
395 u = NGX_HTTP_REFERER_NO_URI_PART;
|
|
396
|
|
397 } else {
|
|
398 u = ngx_palloc(cf->pool, sizeof(ngx_str_t));
|
|
399 if (u == NULL) {
|
|
400 return NGX_CONF_ERROR;
|
|
401 }
|
|
402
|
|
403 *u = *uri;
|
|
404 }
|
|
405
|
|
406 rc = ngx_hash_add_key(keys, value, u, flags);
|
142
|
407
|
|
408 if (rc == NGX_OK) {
|
|
409 return NGX_CONF_OK;
|
|
410 }
|
|
411
|
|
412 if (rc == NGX_BUSY) {
|
|
413 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
|
|
414 "conflicting parameter \"%V\"", value);
|
|
415 }
|
|
416
|
|
417 return NGX_CONF_ERROR;
|
|
418 }
|
|
419
|
|
420
|
|
421 static int ngx_libc_cdecl
|
|
422 ngx_http_cmp_referer_wildcards(const void *one, const void *two)
|
|
423 {
|
|
424 ngx_hash_key_t *first, *second;
|
|
425
|
|
426 first = (ngx_hash_key_t *) one;
|
|
427 second = (ngx_hash_key_t *) two;
|
|
428
|
|
429 return ngx_strcmp(first->key.data, second->key.data);
|
|
430 }
|