1
2 /*
3 * Copyright (C) Igor Sysoev
4 * Copyright (C) Nginx, Inc.
5 */
6
7
8 #include <ngx_config.h>
9 #include <ngx_core.h>
10 #include <ngx_http.h>
11
12 #include <zlib.h>
13
14
15 typedef struct {
16 ngx_flag_t enable;
17 ngx_flag_t no_buffer;
18
19 ngx_hash_t types;
20
21 ngx_bufs_t bufs;
22
23 size_t postpone_gzipping;
24 ngx_int_t level;
25 size_t wbits;
26 size_t memlevel;
27 ssize_t min_length;
28
29 ngx_array_t *types_keys;
30 } ngx_http_gzip_conf_t;
31
32
33 typedef struct {
34 ngx_chain_t *in;
35 ngx_chain_t *free;
36 ngx_chain_t *busy;
37 ngx_chain_t *out;
38 ngx_chain_t **last_out;
39
40 ngx_chain_t *copied;
41 ngx_chain_t *copy_buf;
42
43 ngx_buf_t *in_buf;
44 ngx_buf_t *out_buf;
45 ngx_int_t bufs;
46
47 void *preallocated;
48 char *free_mem;
49 ngx_uint_t allocated;
50
51 int wbits;
52 int memlevel;
53
54 unsigned flush:4;
55 unsigned redo:1;
56 unsigned done:1;
57 unsigned nomem:1;
58 unsigned gzheader:1;
59 unsigned buffering:1;
60 unsigned intel:1;
61
62 size_t zin;
63 size_t zout;
64
65 uint32_t crc32;
66 z_stream zstream;
67 ngx_http_request_t *request;
68 } ngx_http_gzip_ctx_t;
69
70
71 #if (NGX_HAVE_LITTLE_ENDIAN && NGX_HAVE_NONALIGNED)
72
73 struct gztrailer {
74 uint32_t crc32;
75 uint32_t zlen;
76 };
77
78 #else /* NGX_HAVE_BIG_ENDIAN || !NGX_HAVE_NONALIGNED */
79
80 struct gztrailer {
81 u_char crc32[4];
82 u_char zlen[4];
83 };
84
85 #endif
86
87
88 static void ngx_http_gzip_filter_memory(ngx_http_request_t *r,
89 ngx_http_gzip_ctx_t *ctx);
90 static ngx_int_t ngx_http_gzip_filter_buffer(ngx_http_gzip_ctx_t *ctx,
91 ngx_chain_t *in);
92 static ngx_int_t ngx_http_gzip_filter_deflate_start(ngx_http_request_t *r,
93 ngx_http_gzip_ctx_t *ctx);
94 static ngx_int_t ngx_http_gzip_filter_gzheader(ngx_http_request_t *r,
95 ngx_http_gzip_ctx_t *ctx);
96 static ngx_int_t ngx_http_gzip_filter_add_data(ngx_http_request_t *r,
97 ngx_http_gzip_ctx_t *ctx);
98 static ngx_int_t ngx_http_gzip_filter_get_buf(ngx_http_request_t *r,
99 ngx_http_gzip_ctx_t *ctx);
100 static ngx_int_t ngx_http_gzip_filter_deflate(ngx_http_request_t *r,
101 ngx_http_gzip_ctx_t *ctx);
102 static ngx_int_t ngx_http_gzip_filter_deflate_end(ngx_http_request_t *r,
103 ngx_http_gzip_ctx_t *ctx);
104
105 static void *ngx_http_gzip_filter_alloc(void *opaque, u_int items,
106 u_int size);
107 static void ngx_http_gzip_filter_free(void *opaque, void *address);
108 static void ngx_http_gzip_filter_free_copy_buf(ngx_http_request_t *r,
109 ngx_http_gzip_ctx_t *ctx);
110
111 static ngx_int_t ngx_http_gzip_add_variables(ngx_conf_t *cf);
112 static ngx_int_t ngx_http_gzip_ratio_variable(ngx_http_request_t *r,
113 ngx_http_variable_value_t *v, uintptr_t data);
114
115 static ngx_int_t ngx_http_gzip_filter_init(ngx_conf_t *cf);
116 static void *ngx_http_gzip_create_conf(ngx_conf_t *cf);
117 static char *ngx_http_gzip_merge_conf(ngx_conf_t *cf,
118 void *parent, void *child);
119 static char *ngx_http_gzip_window(ngx_conf_t *cf, void *post, void *data);
120 static char *ngx_http_gzip_hash(ngx_conf_t *cf, void *post, void *data);
121
122
123 static ngx_conf_num_bounds_t ngx_http_gzip_comp_level_bounds = {
124 ngx_conf_check_num_bounds, 1, 9
125 };
126
127 static ngx_conf_post_handler_pt ngx_http_gzip_window_p = ngx_http_gzip_window;
128 static ngx_conf_post_handler_pt ngx_http_gzip_hash_p = ngx_http_gzip_hash;
129
130
131 static ngx_command_t ngx_http_gzip_filter_commands[] = {
132
133 { ngx_string("gzip"),
134 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
135 |NGX_CONF_FLAG,
136 ngx_conf_set_flag_slot,
137 NGX_HTTP_LOC_CONF_OFFSET,
138 offsetof(ngx_http_gzip_conf_t, enable),
139 NULL },
140
141 { ngx_string("gzip_buffers"),
142 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE2,
143 ngx_conf_set_bufs_slot,
144 NGX_HTTP_LOC_CONF_OFFSET,
145 offsetof(ngx_http_gzip_conf_t, bufs),
146 NULL },
147
148 { ngx_string("gzip_types"),
149 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
150 ngx_http_types_slot,
151 NGX_HTTP_LOC_CONF_OFFSET,
152 offsetof(ngx_http_gzip_conf_t, types_keys),
153 &ngx_http_html_default_types[0] },
154
155 { ngx_string("gzip_comp_level"),
156 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
157 ngx_conf_set_num_slot,
158 NGX_HTTP_LOC_CONF_OFFSET,
159 offsetof(ngx_http_gzip_conf_t, level),
160 &ngx_http_gzip_comp_level_bounds },
161
162 { ngx_string("gzip_window"),
163 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
164 ngx_conf_set_size_slot,
165 NGX_HTTP_LOC_CONF_OFFSET,
166 offsetof(ngx_http_gzip_conf_t, wbits),
167 &ngx_http_gzip_window_p },
168
169 { ngx_string("gzip_hash"),
170 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
171 ngx_conf_set_size_slot,
172 NGX_HTTP_LOC_CONF_OFFSET,
173 offsetof(ngx_http_gzip_conf_t, memlevel),
174 &ngx_http_gzip_hash_p },
175
176 { ngx_string("postpone_gzipping"),
177 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
178 ngx_conf_set_size_slot,
179 NGX_HTTP_LOC_CONF_OFFSET,
180 offsetof(ngx_http_gzip_conf_t, postpone_gzipping),
181 NULL },
182
183 { ngx_string("gzip_no_buffer"),
184 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
185 ngx_conf_set_flag_slot,
186 NGX_HTTP_LOC_CONF_OFFSET,
187 offsetof(ngx_http_gzip_conf_t, no_buffer),
188 NULL },
189
190 { ngx_string("gzip_min_length"),
191 NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
192 ngx_conf_set_size_slot,
193 NGX_HTTP_LOC_CONF_OFFSET,
194 offsetof(ngx_http_gzip_conf_t, min_length),
195 NULL },
196
197 ngx_null_command
198 };
199
200
201 static ngx_http_module_t ngx_http_gzip_filter_module_ctx = {
202 ngx_http_gzip_add_variables, /* preconfiguration */
203 ngx_http_gzip_filter_init, /* postconfiguration */
204
205 NULL, /* create main configuration */
206 NULL, /* init main configuration */
207
208 NULL, /* create server configuration */
209 NULL, /* merge server configuration */
210
211 ngx_http_gzip_create_conf, /* create location configuration */
212 ngx_http_gzip_merge_conf /* merge location configuration */
213 };
214
215
216 ngx_module_t ngx_http_gzip_filter_module = {
217 NGX_MODULE_V1,
218 &ngx_http_gzip_filter_module_ctx, /* module context */
219 ngx_http_gzip_filter_commands, /* module directives */
220 NGX_HTTP_MODULE, /* module type */
221 NULL, /* init master */
222 NULL, /* init module */
223 NULL, /* init process */
224 NULL, /* init thread */
225 NULL, /* exit thread */
226 NULL, /* exit process */
227 NULL, /* exit master */
228 NGX_MODULE_V1_PADDING
229 };
230
231
232 static ngx_str_t ngx_http_gzip_ratio = ngx_string("gzip_ratio");
233
234 static ngx_http_output_header_filter_pt ngx_http_next_header_filter;
235 static ngx_http_output_body_filter_pt ngx_http_next_body_filter;
236
237 static ngx_uint_t ngx_http_gzip_assume_intel;
238
239
240 static ngx_int_t
ngx_http_gzip_header_filter(ngx_http_request_t * r)241 ngx_http_gzip_header_filter(ngx_http_request_t *r)
242 {
243 ngx_table_elt_t *h;
244 ngx_http_gzip_ctx_t *ctx;
245 ngx_http_gzip_conf_t *conf;
246
247 conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
248
249 if (!conf->enable
250 || (r->headers_out.status != NGX_HTTP_OK
251 && r->headers_out.status != NGX_HTTP_FORBIDDEN
252 && r->headers_out.status != NGX_HTTP_NOT_FOUND)
253 || (r->headers_out.content_encoding
254 && r->headers_out.content_encoding->value.len)
255 || (r->headers_out.content_length_n != -1
256 && r->headers_out.content_length_n < conf->min_length)
257 || ngx_http_test_content_type(r, &conf->types) == NULL
258 || r->header_only)
259 {
260 return ngx_http_next_header_filter(r);
261 }
262
263 r->gzip_vary = 1;
264
265 #if (NGX_HTTP_DEGRADATION)
266 {
267 ngx_http_core_loc_conf_t *clcf;
268
269 clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
270
271 if (clcf->gzip_disable_degradation && ngx_http_degraded(r)) {
272 return ngx_http_next_header_filter(r);
273 }
274 }
275 #endif
276
277 if (!r->gzip_tested) {
278 if (ngx_http_gzip_ok(r) != NGX_OK) {
279 return ngx_http_next_header_filter(r);
280 }
281
282 } else if (!r->gzip_ok) {
283 return ngx_http_next_header_filter(r);
284 }
285
286 ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_gzip_ctx_t));
287 if (ctx == NULL) {
288 return NGX_ERROR;
289 }
290
291 ngx_http_set_ctx(r, ctx, ngx_http_gzip_filter_module);
292
293 ctx->request = r;
294 ctx->buffering = (conf->postpone_gzipping != 0);
295
296 ngx_http_gzip_filter_memory(r, ctx);
297
298 h = ngx_list_push(&r->headers_out.headers);
299 if (h == NULL) {
300 return NGX_ERROR;
301 }
302
303 h->hash = 1;
304 ngx_str_set(&h->key, "Content-Encoding");
305 ngx_str_set(&h->value, "gzip");
306 r->headers_out.content_encoding = h;
307
308 r->main_filter_need_in_memory = 1;
309
310 ngx_http_clear_content_length(r);
311 ngx_http_clear_accept_ranges(r);
312 ngx_http_weak_etag(r);
313
314 return ngx_http_next_header_filter(r);
315 }
316
317
318 static ngx_int_t
ngx_http_gzip_body_filter(ngx_http_request_t * r,ngx_chain_t * in)319 ngx_http_gzip_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
320 {
321 int rc;
322 ngx_uint_t flush;
323 ngx_chain_t *cl;
324 ngx_http_gzip_ctx_t *ctx;
325
326 ctx = ngx_http_get_module_ctx(r, ngx_http_gzip_filter_module);
327
328 if (ctx == NULL || ctx->done || r->header_only) {
329 return ngx_http_next_body_filter(r, in);
330 }
331
332 ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
333 "http gzip filter");
334
335 if (ctx->buffering) {
336
337 /*
338 * With default memory settings zlib starts to output gzipped data
339 * only after it has got about 90K, so it makes sense to allocate
340 * zlib memory (200-400K) only after we have enough data to compress.
341 * Although we copy buffers, nevertheless for not big responses
342 * this allows to allocate zlib memory, to compress and to output
343 * the response in one step using hot CPU cache.
344 */
345
346 if (in) {
347 switch (ngx_http_gzip_filter_buffer(ctx, in)) {
348
349 case NGX_OK:
350 return NGX_OK;
351
352 case NGX_DONE:
353 in = NULL;
354 break;
355
356 default: /* NGX_ERROR */
357 goto failed;
358 }
359
360 } else {
361 ctx->buffering = 0;
362 }
363 }
364
365 if (ctx->preallocated == NULL) {
366 if (ngx_http_gzip_filter_deflate_start(r, ctx) != NGX_OK) {
367 goto failed;
368 }
369 }
370
371 if (in) {
372 if (ngx_chain_add_copy(r->pool, &ctx->in, in) != NGX_OK) {
373 goto failed;
374 }
375
376 r->connection->buffered |= NGX_HTTP_GZIP_BUFFERED;
377 }
378
379 if (ctx->nomem) {
380
381 /* flush busy buffers */
382
383 if (ngx_http_next_body_filter(r, NULL) == NGX_ERROR) {
384 goto failed;
385 }
386
387 cl = NULL;
388
389 ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &cl,
390 (ngx_buf_tag_t) &ngx_http_gzip_filter_module);
391 ctx->nomem = 0;
392 flush = 0;
393
394 } else {
395 flush = ctx->busy ? 1 : 0;
396 }
397
398 for ( ;; ) {
399
400 /* cycle while we can write to a client */
401
402 for ( ;; ) {
403
404 /* cycle while there is data to feed zlib and ... */
405
406 rc = ngx_http_gzip_filter_add_data(r, ctx);
407
408 if (rc == NGX_DECLINED) {
409 break;
410 }
411
412 if (rc == NGX_AGAIN) {
413 continue;
414 }
415
416
417 /* ... there are buffers to write zlib output */
418
419 rc = ngx_http_gzip_filter_get_buf(r, ctx);
420
421 if (rc == NGX_DECLINED) {
422 break;
423 }
424
425 if (rc == NGX_ERROR) {
426 goto failed;
427 }
428
429
430 rc = ngx_http_gzip_filter_deflate(r, ctx);
431
432 if (rc == NGX_OK) {
433 break;
434 }
435
436 if (rc == NGX_ERROR) {
437 goto failed;
438 }
439
440 /* rc == NGX_AGAIN */
441 }
442
443 if (ctx->out == NULL && !flush) {
444 ngx_http_gzip_filter_free_copy_buf(r, ctx);
445
446 return ctx->busy ? NGX_AGAIN : NGX_OK;
447 }
448
449 if (!ctx->gzheader) {
450 if (ngx_http_gzip_filter_gzheader(r, ctx) != NGX_OK) {
451 goto failed;
452 }
453 }
454
455 rc = ngx_http_next_body_filter(r, ctx->out);
456
457 if (rc == NGX_ERROR) {
458 goto failed;
459 }
460
461 ngx_http_gzip_filter_free_copy_buf(r, ctx);
462
463 ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &ctx->out,
464 (ngx_buf_tag_t) &ngx_http_gzip_filter_module);
465 ctx->last_out = &ctx->out;
466
467 ctx->nomem = 0;
468 flush = 0;
469
470 if (ctx->done) {
471 return rc;
472 }
473 }
474
475 /* unreachable */
476
477 failed:
478
479 ctx->done = 1;
480
481 if (ctx->preallocated) {
482 deflateEnd(&ctx->zstream);
483
484 ngx_pfree(r->pool, ctx->preallocated);
485 }
486
487 ngx_http_gzip_filter_free_copy_buf(r, ctx);
488
489 return NGX_ERROR;
490 }
491
492
493 static void
ngx_http_gzip_filter_memory(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)494 ngx_http_gzip_filter_memory(ngx_http_request_t *r, ngx_http_gzip_ctx_t *ctx)
495 {
496 int wbits, memlevel;
497 ngx_http_gzip_conf_t *conf;
498
499 conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
500
501 wbits = conf->wbits;
502 memlevel = conf->memlevel;
503
504 if (r->headers_out.content_length_n > 0) {
505
506 /* the actual zlib window size is smaller by 262 bytes */
507
508 while (r->headers_out.content_length_n < ((1 << (wbits - 1)) - 262)) {
509 wbits--;
510 memlevel--;
511 }
512
513 if (memlevel < 1) {
514 memlevel = 1;
515 }
516 }
517
518 ctx->wbits = wbits;
519 ctx->memlevel = memlevel;
520
521 /*
522 * We preallocate a memory for zlib in one buffer (200K-400K), this
523 * decreases a number of malloc() and free() calls and also probably
524 * decreases a number of syscalls (sbrk()/mmap() and so on).
525 * Besides we free the memory as soon as a gzipping will complete
526 * and do not wait while a whole response will be sent to a client.
527 *
528 * 8K is for zlib deflate_state, it takes
529 * *) 5816 bytes on i386 and sparc64 (32-bit mode)
530 * *) 5920 bytes on amd64 and sparc64
531 */
532
533 if (!ngx_http_gzip_assume_intel) {
534 ctx->allocated = 8192 + (1 << (wbits + 2)) + (1 << (memlevel + 9));
535
536 } else {
537 /*
538 * A zlib variant from Intel, https://github.com/jtkukunas/zlib.
539 * It can force window bits to 13 for fast compression level,
540 * on processors with SSE 4.2 it uses 64K hash instead of scaling
541 * it from the specified memory level, and also introduces
542 * 16-byte padding in one out of the two window-sized buffers.
543 */
544
545 if (conf->level == 1) {
546 wbits = ngx_max(wbits, 13);
547 }
548
549 ctx->allocated = 8192 + 16 + (1 << (wbits + 2))
550 + (1 << (ngx_max(memlevel, 8) + 8))
551 + (1 << (memlevel + 8));
552 ctx->intel = 1;
553 }
554 }
555
556
557 static ngx_int_t
ngx_http_gzip_filter_buffer(ngx_http_gzip_ctx_t * ctx,ngx_chain_t * in)558 ngx_http_gzip_filter_buffer(ngx_http_gzip_ctx_t *ctx, ngx_chain_t *in)
559 {
560 size_t size, buffered;
561 ngx_buf_t *b, *buf;
562 ngx_chain_t *cl, **ll;
563 ngx_http_request_t *r;
564 ngx_http_gzip_conf_t *conf;
565
566 r = ctx->request;
567
568 r->connection->buffered |= NGX_HTTP_GZIP_BUFFERED;
569
570 buffered = 0;
571 ll = &ctx->in;
572
573 for (cl = ctx->in; cl; cl = cl->next) {
574 buffered += cl->buf->last - cl->buf->pos;
575 ll = &cl->next;
576 }
577
578 conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
579
580 while (in) {
581 cl = ngx_alloc_chain_link(r->pool);
582 if (cl == NULL) {
583 return NGX_ERROR;
584 }
585
586 b = in->buf;
587
588 size = b->last - b->pos;
589 buffered += size;
590
591 if (b->flush || b->last_buf || buffered > conf->postpone_gzipping) {
592 ctx->buffering = 0;
593 }
594
595 if (ctx->buffering && size) {
596
597 buf = ngx_create_temp_buf(r->pool, size);
598 if (buf == NULL) {
599 return NGX_ERROR;
600 }
601
602 buf->last = ngx_cpymem(buf->pos, b->pos, size);
603 b->pos = b->last;
604
605 buf->last_buf = b->last_buf;
606 buf->tag = (ngx_buf_tag_t) &ngx_http_gzip_filter_module;
607
608 cl->buf = buf;
609
610 } else {
611 cl->buf = b;
612 }
613
614 *ll = cl;
615 ll = &cl->next;
616 in = in->next;
617 }
618
619 *ll = NULL;
620
621 return ctx->buffering ? NGX_OK : NGX_DONE;
622 }
623
624
625 static ngx_int_t
ngx_http_gzip_filter_deflate_start(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)626 ngx_http_gzip_filter_deflate_start(ngx_http_request_t *r,
627 ngx_http_gzip_ctx_t *ctx)
628 {
629 int rc;
630 ngx_http_gzip_conf_t *conf;
631
632 conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
633
634 ctx->preallocated = ngx_palloc(r->pool, ctx->allocated);
635 if (ctx->preallocated == NULL) {
636 return NGX_ERROR;
637 }
638
639 ctx->free_mem = ctx->preallocated;
640
641 ctx->zstream.zalloc = ngx_http_gzip_filter_alloc;
642 ctx->zstream.zfree = ngx_http_gzip_filter_free;
643 ctx->zstream.opaque = ctx;
644
645 rc = deflateInit2(&ctx->zstream, (int) conf->level, Z_DEFLATED,
646 - ctx->wbits, ctx->memlevel, Z_DEFAULT_STRATEGY);
647
648 if (rc != Z_OK) {
649 ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
650 "deflateInit2() failed: %d", rc);
651 return NGX_ERROR;
652 }
653
654 ctx->last_out = &ctx->out;
655 ctx->crc32 = crc32(0L, Z_NULL, 0);
656 ctx->flush = Z_NO_FLUSH;
657
658 return NGX_OK;
659 }
660
661
662 static ngx_int_t
ngx_http_gzip_filter_gzheader(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)663 ngx_http_gzip_filter_gzheader(ngx_http_request_t *r, ngx_http_gzip_ctx_t *ctx)
664 {
665 ngx_buf_t *b;
666 ngx_chain_t *cl;
667 static u_char gzheader[10] =
668 { 0x1f, 0x8b, Z_DEFLATED, 0, 0, 0, 0, 0, 0, 3 };
669
670 b = ngx_calloc_buf(r->pool);
671 if (b == NULL) {
672 return NGX_ERROR;
673 }
674
675 b->memory = 1;
676 b->pos = gzheader;
677 b->last = b->pos + 10;
678
679 cl = ngx_alloc_chain_link(r->pool);
680 if (cl == NULL) {
681 return NGX_ERROR;
682 }
683
684 cl->buf = b;
685 cl->next = ctx->out;
686 ctx->out = cl;
687
688 ctx->gzheader = 1;
689
690 return NGX_OK;
691 }
692
693
694 static ngx_int_t
ngx_http_gzip_filter_add_data(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)695 ngx_http_gzip_filter_add_data(ngx_http_request_t *r, ngx_http_gzip_ctx_t *ctx)
696 {
697 ngx_chain_t *cl;
698
699 if (ctx->zstream.avail_in || ctx->flush != Z_NO_FLUSH || ctx->redo) {
700 return NGX_OK;
701 }
702
703 ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
704 "gzip in: %p", ctx->in);
705
706 if (ctx->in == NULL) {
707 return NGX_DECLINED;
708 }
709
710 if (ctx->copy_buf) {
711
712 /*
713 * to avoid CPU cache trashing we do not free() just quit buf,
714 * but postpone free()ing after zlib compressing and data output
715 */
716
717 ctx->copy_buf->next = ctx->copied;
718 ctx->copied = ctx->copy_buf;
719 ctx->copy_buf = NULL;
720 }
721
722 cl = ctx->in;
723 ctx->in_buf = cl->buf;
724 ctx->in = cl->next;
725
726 if (ctx->in_buf->tag == (ngx_buf_tag_t) &ngx_http_gzip_filter_module) {
727 ctx->copy_buf = cl;
728
729 } else {
730 ngx_free_chain(r->pool, cl);
731 }
732
733 ctx->zstream.next_in = ctx->in_buf->pos;
734 ctx->zstream.avail_in = ctx->in_buf->last - ctx->in_buf->pos;
735
736 ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
737 "gzip in_buf:%p ni:%p ai:%ud",
738 ctx->in_buf,
739 ctx->zstream.next_in, ctx->zstream.avail_in);
740
741 if (ctx->in_buf->last_buf) {
742 ctx->flush = Z_FINISH;
743
744 } else if (ctx->in_buf->flush) {
745 ctx->flush = Z_SYNC_FLUSH;
746 }
747
748 if (ctx->zstream.avail_in) {
749
750 ctx->crc32 = crc32(ctx->crc32, ctx->zstream.next_in,
751 ctx->zstream.avail_in);
752
753 } else if (ctx->flush == Z_NO_FLUSH) {
754 return NGX_AGAIN;
755 }
756
757 return NGX_OK;
758 }
759
760
761 static ngx_int_t
ngx_http_gzip_filter_get_buf(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)762 ngx_http_gzip_filter_get_buf(ngx_http_request_t *r, ngx_http_gzip_ctx_t *ctx)
763 {
764 ngx_chain_t *cl;
765 ngx_http_gzip_conf_t *conf;
766
767 if (ctx->zstream.avail_out) {
768 return NGX_OK;
769 }
770
771 conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
772
773 if (ctx->free) {
774
775 cl = ctx->free;
776 ctx->out_buf = cl->buf;
777 ctx->free = cl->next;
778
779 ngx_free_chain(r->pool, cl);
780
781 } else if (ctx->bufs < conf->bufs.num) {
782
783 ctx->out_buf = ngx_create_temp_buf(r->pool, conf->bufs.size);
784 if (ctx->out_buf == NULL) {
785 return NGX_ERROR;
786 }
787
788 ctx->out_buf->tag = (ngx_buf_tag_t) &ngx_http_gzip_filter_module;
789 ctx->out_buf->recycled = 1;
790 ctx->bufs++;
791
792 } else {
793 ctx->nomem = 1;
794 return NGX_DECLINED;
795 }
796
797 ctx->zstream.next_out = ctx->out_buf->pos;
798 ctx->zstream.avail_out = conf->bufs.size;
799
800 return NGX_OK;
801 }
802
803
804 static ngx_int_t
ngx_http_gzip_filter_deflate(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)805 ngx_http_gzip_filter_deflate(ngx_http_request_t *r, ngx_http_gzip_ctx_t *ctx)
806 {
807 int rc;
808 ngx_buf_t *b;
809 ngx_chain_t *cl;
810 ngx_http_gzip_conf_t *conf;
811
812 ngx_log_debug6(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
813 "deflate in: ni:%p no:%p ai:%ud ao:%ud fl:%d redo:%d",
814 ctx->zstream.next_in, ctx->zstream.next_out,
815 ctx->zstream.avail_in, ctx->zstream.avail_out,
816 ctx->flush, ctx->redo);
817
818 rc = deflate(&ctx->zstream, ctx->flush);
819
820 if (rc != Z_OK && rc != Z_STREAM_END && rc != Z_BUF_ERROR) {
821 ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
822 "deflate() failed: %d, %d", ctx->flush, rc);
823 return NGX_ERROR;
824 }
825
826 ngx_log_debug5(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
827 "deflate out: ni:%p no:%p ai:%ud ao:%ud rc:%d",
828 ctx->zstream.next_in, ctx->zstream.next_out,
829 ctx->zstream.avail_in, ctx->zstream.avail_out,
830 rc);
831
832 ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
833 "gzip in_buf:%p pos:%p",
834 ctx->in_buf, ctx->in_buf->pos);
835
836 if (ctx->zstream.next_in) {
837 ctx->in_buf->pos = ctx->zstream.next_in;
838
839 if (ctx->zstream.avail_in == 0) {
840 ctx->zstream.next_in = NULL;
841 }
842 }
843
844 ctx->out_buf->last = ctx->zstream.next_out;
845
846 if (ctx->zstream.avail_out == 0) {
847
848 /* zlib wants to output some more gzipped data */
849
850 cl = ngx_alloc_chain_link(r->pool);
851 if (cl == NULL) {
852 return NGX_ERROR;
853 }
854
855 cl->buf = ctx->out_buf;
856 cl->next = NULL;
857 *ctx->last_out = cl;
858 ctx->last_out = &cl->next;
859
860 ctx->redo = 1;
861
862 return NGX_AGAIN;
863 }
864
865 ctx->redo = 0;
866
867 if (ctx->flush == Z_SYNC_FLUSH) {
868
869 ctx->flush = Z_NO_FLUSH;
870
871 cl = ngx_alloc_chain_link(r->pool);
872 if (cl == NULL) {
873 return NGX_ERROR;
874 }
875
876 b = ctx->out_buf;
877
878 if (ngx_buf_size(b) == 0) {
879
880 b = ngx_calloc_buf(ctx->request->pool);
881 if (b == NULL) {
882 return NGX_ERROR;
883 }
884
885 } else {
886 ctx->zstream.avail_out = 0;
887 }
888
889 b->flush = 1;
890
891 cl->buf = b;
892 cl->next = NULL;
893 *ctx->last_out = cl;
894 ctx->last_out = &cl->next;
895
896 r->connection->buffered &= ~NGX_HTTP_GZIP_BUFFERED;
897
898 return NGX_OK;
899 }
900
901 if (rc == Z_STREAM_END) {
902
903 if (ngx_http_gzip_filter_deflate_end(r, ctx) != NGX_OK) {
904 return NGX_ERROR;
905 }
906
907 return NGX_OK;
908 }
909
910 conf = ngx_http_get_module_loc_conf(r, ngx_http_gzip_filter_module);
911
912 if (conf->no_buffer && ctx->in == NULL) {
913
914 cl = ngx_alloc_chain_link(r->pool);
915 if (cl == NULL) {
916 return NGX_ERROR;
917 }
918
919 cl->buf = ctx->out_buf;
920 cl->next = NULL;
921 *ctx->last_out = cl;
922 ctx->last_out = &cl->next;
923
924 return NGX_OK;
925 }
926
927 return NGX_AGAIN;
928 }
929
930
931 static ngx_int_t
ngx_http_gzip_filter_deflate_end(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)932 ngx_http_gzip_filter_deflate_end(ngx_http_request_t *r,
933 ngx_http_gzip_ctx_t *ctx)
934 {
935 int rc;
936 ngx_buf_t *b;
937 ngx_chain_t *cl;
938 struct gztrailer *trailer;
939
940 ctx->zin = ctx->zstream.total_in;
941 ctx->zout = 10 + ctx->zstream.total_out + 8;
942
943 rc = deflateEnd(&ctx->zstream);
944
945 if (rc != Z_OK) {
946 ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
947 "deflateEnd() failed: %d", rc);
948 return NGX_ERROR;
949 }
950
951 ngx_pfree(r->pool, ctx->preallocated);
952
953 cl = ngx_alloc_chain_link(r->pool);
954 if (cl == NULL) {
955 return NGX_ERROR;
956 }
957
958 cl->buf = ctx->out_buf;
959 cl->next = NULL;
960 *ctx->last_out = cl;
961 ctx->last_out = &cl->next;
962
963 if (ctx->zstream.avail_out >= 8) {
964 trailer = (struct gztrailer *) ctx->out_buf->last;
965 ctx->out_buf->last += 8;
966 ctx->out_buf->last_buf = 1;
967
968 } else {
969 b = ngx_create_temp_buf(r->pool, 8);
970 if (b == NULL) {
971 return NGX_ERROR;
972 }
973
974 b->last_buf = 1;
975
976 cl = ngx_alloc_chain_link(r->pool);
977 if (cl == NULL) {
978 return NGX_ERROR;
979 }
980
981 cl->buf = b;
982 cl->next = NULL;
983 *ctx->last_out = cl;
984 ctx->last_out = &cl->next;
985 trailer = (struct gztrailer *) b->pos;
986 b->last += 8;
987 }
988
989 #if (NGX_HAVE_LITTLE_ENDIAN && NGX_HAVE_NONALIGNED)
990
991 trailer->crc32 = ctx->crc32;
992 trailer->zlen = ctx->zin;
993
994 #else
995
996 trailer->crc32[0] = (u_char) (ctx->crc32 & 0xff);
997 trailer->crc32[1] = (u_char) ((ctx->crc32 >> 8) & 0xff);
998 trailer->crc32[2] = (u_char) ((ctx->crc32 >> 16) & 0xff);
999 trailer->crc32[3] = (u_char) ((ctx->crc32 >> 24) & 0xff);
1000
1001 trailer->zlen[0] = (u_char) (ctx->zin & 0xff);
1002 trailer->zlen[1] = (u_char) ((ctx->zin >> 8) & 0xff);
1003 trailer->zlen[2] = (u_char) ((ctx->zin >> 16) & 0xff);
1004 trailer->zlen[3] = (u_char) ((ctx->zin >> 24) & 0xff);
1005
1006 #endif
1007
1008 ctx->zstream.avail_in = 0;
1009 ctx->zstream.avail_out = 0;
1010
1011 ctx->done = 1;
1012
1013 r->connection->buffered &= ~NGX_HTTP_GZIP_BUFFERED;
1014
1015 return NGX_OK;
1016 }
1017
1018
1019 static void *
ngx_http_gzip_filter_alloc(void * opaque,u_int items,u_int size)1020 ngx_http_gzip_filter_alloc(void *opaque, u_int items, u_int size)
1021 {
1022 ngx_http_gzip_ctx_t *ctx = opaque;
1023
1024 void *p;
1025 ngx_uint_t alloc;
1026
1027 alloc = items * size;
1028
1029 if (items == 1 && alloc % 512 != 0 && alloc < 8192) {
1030
1031 /*
1032 * The zlib deflate_state allocation, it takes about 6K,
1033 * we allocate 8K. Other allocations are divisible by 512.
1034 */
1035
1036 alloc = 8192;
1037 }
1038
1039 if (alloc <= ctx->allocated) {
1040 p = ctx->free_mem;
1041 ctx->free_mem += alloc;
1042 ctx->allocated -= alloc;
1043
1044 ngx_log_debug4(NGX_LOG_DEBUG_HTTP, ctx->request->connection->log, 0,
1045 "gzip alloc: n:%ud s:%ud a:%ui p:%p",
1046 items, size, alloc, p);
1047
1048 return p;
1049 }
1050
1051 if (ctx->intel) {
1052 ngx_log_error(NGX_LOG_ALERT, ctx->request->connection->log, 0,
1053 "gzip filter failed to use preallocated memory: "
1054 "%ud of %ui", items * size, ctx->allocated);
1055
1056 } else {
1057 ngx_http_gzip_assume_intel = 1;
1058 }
1059
1060 p = ngx_palloc(ctx->request->pool, items * size);
1061
1062 return p;
1063 }
1064
1065
1066 static void
ngx_http_gzip_filter_free(void * opaque,void * address)1067 ngx_http_gzip_filter_free(void *opaque, void *address)
1068 {
1069 #if 0
1070 ngx_http_gzip_ctx_t *ctx = opaque;
1071
1072 ngx_log_debug1(NGX_LOG_DEBUG_HTTP, ctx->request->connection->log, 0,
1073 "gzip free: %p", address);
1074 #endif
1075 }
1076
1077
1078 static void
ngx_http_gzip_filter_free_copy_buf(ngx_http_request_t * r,ngx_http_gzip_ctx_t * ctx)1079 ngx_http_gzip_filter_free_copy_buf(ngx_http_request_t *r,
1080 ngx_http_gzip_ctx_t *ctx)
1081 {
1082 ngx_chain_t *cl;
1083
1084 for (cl = ctx->copied; cl; cl = cl->next) {
1085 ngx_pfree(r->pool, cl->buf->start);
1086 }
1087
1088 ctx->copied = NULL;
1089 }
1090
1091
1092 static ngx_int_t
ngx_http_gzip_add_variables(ngx_conf_t * cf)1093 ngx_http_gzip_add_variables(ngx_conf_t *cf)
1094 {
1095 ngx_http_variable_t *var;
1096
1097 var = ngx_http_add_variable(cf, &ngx_http_gzip_ratio, NGX_HTTP_VAR_NOHASH);
1098 if (var == NULL) {
1099 return NGX_ERROR;
1100 }
1101
1102 var->get_handler = ngx_http_gzip_ratio_variable;
1103
1104 return NGX_OK;
1105 }
1106
1107
1108 static ngx_int_t
ngx_http_gzip_ratio_variable(ngx_http_request_t * r,ngx_http_variable_value_t * v,uintptr_t data)1109 ngx_http_gzip_ratio_variable(ngx_http_request_t *r,
1110 ngx_http_variable_value_t *v, uintptr_t data)
1111 {
1112 ngx_uint_t zint, zfrac;
1113 ngx_http_gzip_ctx_t *ctx;
1114
1115 ctx = ngx_http_get_module_ctx(r, ngx_http_gzip_filter_module);
1116
1117 if (ctx == NULL || ctx->zout == 0) {
1118 v->not_found = 1;
1119 return NGX_OK;
1120 }
1121
1122 v->valid = 1;
1123 v->no_cacheable = 0;
1124 v->not_found = 0;
1125
1126 v->data = ngx_pnalloc(r->pool, NGX_INT32_LEN + 3);
1127 if (v->data == NULL) {
1128 return NGX_ERROR;
1129 }
1130
1131 zint = (ngx_uint_t) (ctx->zin / ctx->zout);
1132 zfrac = (ngx_uint_t) ((ctx->zin * 100 / ctx->zout) % 100);
1133
1134 if ((ctx->zin * 1000 / ctx->zout) % 10 > 4) {
1135
1136 /* the rounding, e.g., 2.125 to 2.13 */
1137
1138 zfrac++;
1139
1140 if (zfrac > 99) {
1141 zint++;
1142 zfrac = 0;
1143 }
1144 }
1145
1146 v->len = ngx_sprintf(v->data, "%ui.%02ui", zint, zfrac) - v->data;
1147
1148 return NGX_OK;
1149 }
1150
1151
1152 static void *
ngx_http_gzip_create_conf(ngx_conf_t * cf)1153 ngx_http_gzip_create_conf(ngx_conf_t *cf)
1154 {
1155 ngx_http_gzip_conf_t *conf;
1156
1157 conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_gzip_conf_t));
1158 if (conf == NULL) {
1159 return NULL;
1160 }
1161
1162 /*
1163 * set by ngx_pcalloc():
1164 *
1165 * conf->bufs.num = 0;
1166 * conf->types = { NULL };
1167 * conf->types_keys = NULL;
1168 */
1169
1170 conf->enable = NGX_CONF_UNSET;
1171 conf->no_buffer = NGX_CONF_UNSET;
1172
1173 conf->postpone_gzipping = NGX_CONF_UNSET_SIZE;
1174 conf->level = NGX_CONF_UNSET;
1175 conf->wbits = NGX_CONF_UNSET_SIZE;
1176 conf->memlevel = NGX_CONF_UNSET_SIZE;
1177 conf->min_length = NGX_CONF_UNSET;
1178
1179 return conf;
1180 }
1181
1182
1183 static char *
ngx_http_gzip_merge_conf(ngx_conf_t * cf,void * parent,void * child)1184 ngx_http_gzip_merge_conf(ngx_conf_t *cf, void *parent, void *child)
1185 {
1186 ngx_http_gzip_conf_t *prev = parent;
1187 ngx_http_gzip_conf_t *conf = child;
1188
1189 ngx_conf_merge_value(conf->enable, prev->enable, 0);
1190 ngx_conf_merge_value(conf->no_buffer, prev->no_buffer, 0);
1191
1192 ngx_conf_merge_bufs_value(conf->bufs, prev->bufs,
1193 (128 * 1024) / ngx_pagesize, ngx_pagesize);
1194
1195 ngx_conf_merge_size_value(conf->postpone_gzipping, prev->postpone_gzipping,
1196 0);
1197 ngx_conf_merge_value(conf->level, prev->level, 1);
1198 ngx_conf_merge_size_value(conf->wbits, prev->wbits, MAX_WBITS);
1199 ngx_conf_merge_size_value(conf->memlevel, prev->memlevel,
1200 MAX_MEM_LEVEL - 1);
1201 ngx_conf_merge_value(conf->min_length, prev->min_length, 20);
1202
1203 if (ngx_http_merge_types(cf, &conf->types_keys, &conf->types,
1204 &prev->types_keys, &prev->types,
1205 ngx_http_html_default_types)
1206 != NGX_OK)
1207 {
1208 return NGX_CONF_ERROR;
1209 }
1210
1211 return NGX_CONF_OK;
1212 }
1213
1214
1215 static ngx_int_t
ngx_http_gzip_filter_init(ngx_conf_t * cf)1216 ngx_http_gzip_filter_init(ngx_conf_t *cf)
1217 {
1218 ngx_http_next_header_filter = ngx_http_top_header_filter;
1219 ngx_http_top_header_filter = ngx_http_gzip_header_filter;
1220
1221 ngx_http_next_body_filter = ngx_http_top_body_filter;
1222 ngx_http_top_body_filter = ngx_http_gzip_body_filter;
1223
1224 return NGX_OK;
1225 }
1226
1227
1228 static char *
ngx_http_gzip_window(ngx_conf_t * cf,void * post,void * data)1229 ngx_http_gzip_window(ngx_conf_t *cf, void *post, void *data)
1230 {
1231 size_t *np = data;
1232
1233 size_t wbits, wsize;
1234
1235 wbits = 15;
1236
1237 for (wsize = 32 * 1024; wsize > 256; wsize >>= 1) {
1238
1239 if (wsize == *np) {
1240 *np = wbits;
1241
1242 return NGX_CONF_OK;
1243 }
1244
1245 wbits--;
1246 }
1247
1248 return "must be 512, 1k, 2k, 4k, 8k, 16k, or 32k";
1249 }
1250
1251
1252 static char *
ngx_http_gzip_hash(ngx_conf_t * cf,void * post,void * data)1253 ngx_http_gzip_hash(ngx_conf_t *cf, void *post, void *data)
1254 {
1255 size_t *np = data;
1256
1257 size_t memlevel, hsize;
1258
1259 memlevel = 9;
1260
1261 for (hsize = 128 * 1024; hsize > 256; hsize >>= 1) {
1262
1263 if (hsize == *np) {
1264 *np = memlevel;
1265
1266 return NGX_CONF_OK;
1267 }
1268
1269 memlevel--;
1270 }
1271
1272 return "must be 512, 1k, 2k, 4k, 8k, 16k, 32k, 64k, or 128k";
1273 }
1274