Klaus Demo nginx / 1c57fb8 src / http / modules / ngx_http_headers_filter_module.c
1c57fb8

Tree @1c57fb8 (Download .tar.gz)

ngx_http_headers_filter_module.c @1c57fb8raw · history · blame

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>


typedef struct ngx_http_header_val_s  ngx_http_header_val_t;

typedef ngx_int_t (*ngx_http_set_header_pt)(ngx_http_request_t *r,
    ngx_http_header_val_t *hv, ngx_str_t *value);


typedef struct {
    ngx_str_t                  name;
    ngx_uint_t                 offset;
    ngx_http_set_header_pt     handler;
} ngx_http_set_header_t;


struct ngx_http_header_val_s {
    ngx_http_complex_value_t   value;
    ngx_uint_t                 hash;
    ngx_str_t                  key;
    ngx_http_set_header_pt     handler;
    ngx_uint_t                 offset;
};


#define NGX_HTTP_EXPIRES_OFF       0
#define NGX_HTTP_EXPIRES_EPOCH     1
#define NGX_HTTP_EXPIRES_MAX       2
#define NGX_HTTP_EXPIRES_ACCESS    3
#define NGX_HTTP_EXPIRES_MODIFIED  4
#define NGX_HTTP_EXPIRES_DAILY     5


typedef struct {
    ngx_uint_t               expires;
    time_t                   expires_time;
    ngx_array_t             *headers;
} ngx_http_headers_conf_t;


static ngx_int_t ngx_http_set_expires(ngx_http_request_t *r,
    ngx_http_headers_conf_t *conf);
static ngx_int_t ngx_http_add_cache_control(ngx_http_request_t *r,
    ngx_http_header_val_t *hv, ngx_str_t *value);
static ngx_int_t ngx_http_set_last_modified(ngx_http_request_t *r,
    ngx_http_header_val_t *hv, ngx_str_t *value);

static void *ngx_http_headers_create_conf(ngx_conf_t *cf);
static char *ngx_http_headers_merge_conf(ngx_conf_t *cf,
    void *parent, void *child);
static ngx_int_t ngx_http_headers_filter_init(ngx_conf_t *cf);
static char *ngx_http_headers_expires(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_http_headers_add(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


static ngx_http_set_header_t  ngx_http_set_headers[] = {

    { ngx_string("Cache-Control"), 0, ngx_http_add_cache_control },

    { ngx_string("Last-Modified"),
                 offsetof(ngx_http_headers_out_t, last_modified),
                 ngx_http_set_last_modified },

    { ngx_null_string, 0, NULL }
};


static ngx_command_t  ngx_http_headers_filter_commands[] = {

    { ngx_string("expires"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                        |NGX_CONF_TAKE12,
      ngx_http_headers_expires,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL},

    { ngx_string("add_header"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                        |NGX_CONF_TAKE2,
      ngx_http_headers_add,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL},

      ngx_null_command
};


static ngx_http_module_t  ngx_http_headers_filter_module_ctx = {
    NULL,                                  /* preconfiguration */
    ngx_http_headers_filter_init,          /* postconfiguration */

    NULL,                                  /* create main configuration */
    NULL,                                  /* init main configuration */

    NULL,                                  /* create server configuration */
    NULL,                                  /* merge server configuration */

    ngx_http_headers_create_conf,          /* create location configuration */
    ngx_http_headers_merge_conf            /* merge location configuration */
};


ngx_module_t  ngx_http_headers_filter_module = {
    NGX_MODULE_V1,
    &ngx_http_headers_filter_module_ctx,   /* module context */
    ngx_http_headers_filter_commands,      /* module directives */
    NGX_HTTP_MODULE,                       /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_http_output_header_filter_pt  ngx_http_next_header_filter;


static ngx_int_t
ngx_http_headers_filter(ngx_http_request_t *r)
{
    ngx_str_t                 value;
    ngx_uint_t                i;
    ngx_http_header_val_t    *h;
    ngx_http_headers_conf_t  *conf;

    conf = ngx_http_get_module_loc_conf(r, ngx_http_headers_filter_module);

    if ((conf->expires == NGX_HTTP_EXPIRES_OFF && conf->headers == NULL)
        || r != r->main
        || (r->headers_out.status != NGX_HTTP_OK
            && r->headers_out.status != NGX_HTTP_NO_CONTENT
            && r->headers_out.status != NGX_HTTP_PARTIAL_CONTENT
            && r->headers_out.status != NGX_HTTP_MOVED_PERMANENTLY
            && r->headers_out.status != NGX_HTTP_MOVED_TEMPORARILY
            && r->headers_out.status != NGX_HTTP_SEE_OTHER
            && r->headers_out.status != NGX_HTTP_NOT_MODIFIED
            && r->headers_out.status != NGX_HTTP_TEMPORARY_REDIRECT))
    {
        return ngx_http_next_header_filter(r);
    }

    if (conf->expires != NGX_HTTP_EXPIRES_OFF) {
        if (ngx_http_set_expires(r, conf) != NGX_OK) {
            return NGX_ERROR;
        }
    }

    if (conf->headers) {
        h = conf->headers->elts;
        for (i = 0; i < conf->headers->nelts; i++) {

            if (ngx_http_complex_value(r, &h[i].value, &value) != NGX_OK) {
                return NGX_ERROR;
            }

            if (h[i].handler(r, &h[i], &value) != NGX_OK) {
                return NGX_ERROR;
            }
        }
    }

    return ngx_http_next_header_filter(r);
}


static ngx_int_t
ngx_http_set_expires(ngx_http_request_t *r, ngx_http_headers_conf_t *conf)
{
    size_t            len;
    time_t            now, expires_time, max_age;
    ngx_uint_t        i;
    ngx_table_elt_t  *expires, *cc, **ccp;

    expires = r->headers_out.expires;

    if (expires == NULL) {

        expires = ngx_list_push(&r->headers_out.headers);
        if (expires == NULL) {
            return NGX_ERROR;
        }

        r->headers_out.expires = expires;

        expires->hash = 1;
        ngx_str_set(&expires->key, "Expires");
    }

    len = sizeof("Mon, 28 Sep 1970 06:00:00 GMT");
    expires->value.len = len - 1;

    ccp = r->headers_out.cache_control.elts;

    if (ccp == NULL) {

        if (ngx_array_init(&r->headers_out.cache_control, r->pool,
                           1, sizeof(ngx_table_elt_t *))
            != NGX_OK)
        {
            return NGX_ERROR;
        }

        ccp = ngx_array_push(&r->headers_out.cache_control);
        if (ccp == NULL) {
            return NGX_ERROR;
        }

        cc = ngx_list_push(&r->headers_out.headers);
        if (cc == NULL) {
            return NGX_ERROR;
        }

        cc->hash = 1;
        ngx_str_set(&cc->key, "Cache-Control");
        *ccp = cc;

    } else {
        for (i = 1; i < r->headers_out.cache_control.nelts; i++) {
            ccp[i]->hash = 0;
        }

        cc = ccp[0];
    }

    if (conf->expires == NGX_HTTP_EXPIRES_EPOCH) {
        expires->value.data = (u_char *) "Thu, 01 Jan 1970 00:00:01 GMT";
        ngx_str_set(&cc->value, "no-cache");
        return NGX_OK;
    }

    if (conf->expires == NGX_HTTP_EXPIRES_MAX) {
        expires->value.data = (u_char *) "Thu, 31 Dec 2037 23:55:55 GMT";
        /* 10 years */
        ngx_str_set(&cc->value, "max-age=315360000");
        return NGX_OK;
    }

    expires->value.data = ngx_pnalloc(r->pool, len);
    if (expires->value.data == NULL) {
        return NGX_ERROR;
    }

    if (conf->expires_time == 0 && conf->expires != NGX_HTTP_EXPIRES_DAILY) {
        ngx_memcpy(expires->value.data, ngx_cached_http_time.data,
                   ngx_cached_http_time.len + 1);
        ngx_str_set(&cc->value, "max-age=0");
        return NGX_OK;
    }

    now = ngx_time();

    if (conf->expires == NGX_HTTP_EXPIRES_DAILY) {
        expires_time = ngx_next_time(conf->expires_time);
        max_age = expires_time - now;

    } else if (conf->expires == NGX_HTTP_EXPIRES_ACCESS
               || r->headers_out.last_modified_time == -1)
    {
        expires_time = now + conf->expires_time;
        max_age = conf->expires_time;

    } else {
        expires_time = r->headers_out.last_modified_time + conf->expires_time;
        max_age = expires_time - now;
    }

    ngx_http_time(expires->value.data, expires_time);

    if (conf->expires_time < 0 || max_age < 0) {
        ngx_str_set(&cc->value, "no-cache");
        return NGX_OK;
    }

    cc->value.data = ngx_pnalloc(r->pool,
                                 sizeof("max-age=") + NGX_TIME_T_LEN + 1);
    if (cc->value.data == NULL) {
        return NGX_ERROR;
    }

    cc->value.len = ngx_sprintf(cc->value.data, "max-age=%T", max_age)
                    - cc->value.data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_add_header(ngx_http_request_t *r, ngx_http_header_val_t *hv,
    ngx_str_t *value)
{
    ngx_table_elt_t  *h;

    if (value->len) {
        h = ngx_list_push(&r->headers_out.headers);
        if (h == NULL) {
            return NGX_ERROR;
        }

        h->hash = hv->hash;
        h->key = hv->key;
        h->value = *value;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_http_add_cache_control(ngx_http_request_t *r, ngx_http_header_val_t *hv,
    ngx_str_t *value)
{
    ngx_table_elt_t  *cc, **ccp;

    ccp = r->headers_out.cache_control.elts;

    if (ccp == NULL) {

        if (ngx_array_init(&r->headers_out.cache_control, r->pool,
                           1, sizeof(ngx_table_elt_t *))
            != NGX_OK)
        {
            return NGX_ERROR;
        }
    }

    ccp = ngx_array_push(&r->headers_out.cache_control);
    if (ccp == NULL) {
        return NGX_ERROR;
    }

    cc = ngx_list_push(&r->headers_out.headers);
    if (cc == NULL) {
        return NGX_ERROR;
    }

    cc->hash = 1;
    ngx_str_set(&cc->key, "Cache-Control");
    cc->value = *value;

    *ccp = cc;

    return NGX_OK;
}


static ngx_int_t
ngx_http_set_last_modified(ngx_http_request_t *r, ngx_http_header_val_t *hv,
    ngx_str_t *value)
{
    ngx_table_elt_t  *h, **old;

    if (hv->offset) {
        old = (ngx_table_elt_t **) ((char *) &r->headers_out + hv->offset);

    } else {
        old = NULL;
    }

    r->headers_out.last_modified_time = -1;

    if (old == NULL || *old == NULL) {

        if (value->len == 0) {
            return NGX_OK;
        }

        h = ngx_list_push(&r->headers_out.headers);
        if (h == NULL) {
            return NGX_ERROR;
        }

    } else {
        h = *old;

        if (value->len == 0) {
            h->hash = 0;
            return NGX_OK;
        }
    }

    h->hash = hv->hash;
    h->key = hv->key;
    h->value = *value;

    return NGX_OK;
}


static void *
ngx_http_headers_create_conf(ngx_conf_t *cf)
{
    ngx_http_headers_conf_t  *conf;

    conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_headers_conf_t));
    if (conf == NULL) {
        return NULL;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     conf->headers = NULL;
     *     conf->expires_time = 0;
     */

    conf->expires = NGX_CONF_UNSET_UINT;

    return conf;
}


static char *
ngx_http_headers_merge_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_headers_conf_t *prev = parent;
    ngx_http_headers_conf_t *conf = child;

    if (conf->expires == NGX_CONF_UNSET_UINT) {
        conf->expires = prev->expires;
        conf->expires_time = prev->expires_time;

        if (conf->expires == NGX_CONF_UNSET_UINT) {
            conf->expires = NGX_HTTP_EXPIRES_OFF;
        }
    }

    if (conf->headers == NULL) {
        conf->headers = prev->headers;
    }

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_http_headers_filter_init(ngx_conf_t *cf)
{
    ngx_http_next_header_filter = ngx_http_top_header_filter;
    ngx_http_top_header_filter = ngx_http_headers_filter;

    return NGX_OK;
}


static char *
ngx_http_headers_expires(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_headers_conf_t *hcf = conf;

    ngx_uint_t   minus, n;
    ngx_str_t   *value;

    if (hcf->expires != NGX_CONF_UNSET_UINT) {
        return "is duplicate";
    }

    value = cf->args->elts;

    if (cf->args->nelts == 2) {

        if (ngx_strcmp(value[1].data, "epoch") == 0) {
            hcf->expires = NGX_HTTP_EXPIRES_EPOCH;
            return NGX_CONF_OK;
        }

        if (ngx_strcmp(value[1].data, "max") == 0) {
            hcf->expires = NGX_HTTP_EXPIRES_MAX;
            return NGX_CONF_OK;
        }

        if (ngx_strcmp(value[1].data, "off") == 0) {
            hcf->expires = NGX_HTTP_EXPIRES_OFF;
            return NGX_CONF_OK;
        }

        hcf->expires = NGX_HTTP_EXPIRES_ACCESS;

        n = 1;

    } else { /* cf->args->nelts == 3 */

        if (ngx_strcmp(value[1].data, "modified") != 0) {
            return "invalid value";
        }

        hcf->expires = NGX_HTTP_EXPIRES_MODIFIED;

        n = 2;
    }

    if (value[n].data[0] == '@') {
        value[n].data++;
        value[n].len--;
        minus = 0;

        if (hcf->expires == NGX_HTTP_EXPIRES_MODIFIED) {
            return "daily time cannot be used with \"modified\" parameter";
        }

        hcf->expires = NGX_HTTP_EXPIRES_DAILY;

    } else if (value[n].data[0] == '+') {
        value[n].data++;
        value[n].len--;
        minus = 0;

    } else if (value[n].data[0] == '-') {
        value[n].data++;
        value[n].len--;
        minus = 1;

    } else {
        minus = 0;
    }

    hcf->expires_time = ngx_parse_time(&value[n], 1);

    if (hcf->expires_time == (time_t) NGX_ERROR) {
        return "invalid value";
    }

    if (hcf->expires == NGX_HTTP_EXPIRES_DAILY
        && hcf->expires_time > 24 * 60 * 60)
    {
        return "daily time value must be less than 24 hours";
    }

    if (minus) {
        hcf->expires_time = - hcf->expires_time;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_headers_add(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_headers_conf_t *hcf = conf;

    ngx_str_t                         *value;
    ngx_uint_t                         i;
    ngx_http_header_val_t             *hv;
    ngx_http_set_header_t             *set;
    ngx_http_compile_complex_value_t   ccv;

    value = cf->args->elts;

    if (hcf->headers == NULL) {
        hcf->headers = ngx_array_create(cf->pool, 1,
                                        sizeof(ngx_http_header_val_t));
        if (hcf->headers == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    hv = ngx_array_push(hcf->headers);
    if (hv == NULL) {
        return NGX_CONF_ERROR;
    }

    hv->hash = 1;
    hv->key = value[1];
    hv->handler = ngx_http_add_header;
    hv->offset = 0;

    set = ngx_http_set_headers;
    for (i = 0; set[i].name.len; i++) {
        if (ngx_strcasecmp(value[1].data, set[i].name.data) != 0) {
            continue;
        }

        hv->offset = set[i].offset;
        hv->handler = set[i].handler;

        break;
    }

    if (value[2].len == 0) {
        ngx_memzero(&hv->value, sizeof(ngx_http_complex_value_t));
        return NGX_CONF_OK;
    }

    ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));

    ccv.cf = cf;
    ccv.value = &value[2];
    ccv.complex_value = &hv->value;

    if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}