1 #include "first.h"
2
3 #include "sys-time.h"
4
5 #include "base.h"
6 #include "array.h"
7 #include "buffer.h"
8 #include "chunk.h"
9 #include "fdevent.h"
10 #include "log.h"
11 #include "http_chunk.h"
12 #include "http_cgi.h"
13 #include "http_date.h"
14 #include "http_etag.h"
15 #include "http_header.h"
16 #include "response.h"
17 #include "sock_addr.h"
18 #include "stat_cache.h"
19
20 #include <stdlib.h>
21 #include <string.h>
22 #include <errno.h>
23
24 #include "sys-socket.h"
25 #include <unistd.h>
26
27 /**
28 * max size of the HTTP response header from backends
29 * (differs from server.max-request-field-size for max request field size)
30 */
31 #define MAX_HTTP_RESPONSE_FIELD_SIZE 65535
32
33
34 __attribute_cold__
http_response_buffer_append_authority(request_st * const r,buffer * const o)35 int http_response_buffer_append_authority(request_st * const r, buffer * const o) {
36 if (!buffer_is_blank(&r->uri.authority)) {
37 buffer_append_string_buffer(o, &r->uri.authority);
38 } else {
39 /* get the name of the currently connected socket */
40 sock_addr our_addr;
41 socklen_t our_addr_len;
42
43 our_addr.plain.sa_family = 0;
44 our_addr_len = sizeof(our_addr);
45
46 if (-1 == getsockname(r->con->fd, (struct sockaddr *)&our_addr, &our_addr_len)
47 || our_addr_len > (socklen_t)sizeof(our_addr)) {
48 r->http_status = 500;
49 log_perror(r->conf.errh, __FILE__, __LINE__, "can't get sockname");
50 return -1;
51 }
52
53 if (our_addr.plain.sa_family == AF_INET
54 && our_addr.ipv4.sin_addr.s_addr == htonl(INADDR_LOOPBACK)) {
55 static char lhost[32];
56 static size_t lhost_len = 0;
57 if (0 != lhost_len) {
58 buffer_append_string_len(o, lhost, lhost_len);
59 }
60 else {
61 size_t olen = buffer_clen(o);
62 if (0 == sock_addr_nameinfo_append_buffer(o, &our_addr, r->conf.errh)) {
63 lhost_len = buffer_clen(o) - olen;
64 if (lhost_len < sizeof(lhost)) {
65 memcpy(lhost, o->ptr+olen, lhost_len+1); /*(+1 for '\0')*/
66 }
67 else {
68 lhost_len = 0;
69 }
70 }
71 else {
72 lhost_len = sizeof("localhost")-1;
73 memcpy(lhost, "localhost", lhost_len+1); /*(+1 for '\0')*/
74 buffer_append_string_len(o, lhost, lhost_len);
75 }
76 }
77 } else if (!buffer_is_blank(r->server_name)) {
78 buffer_append_string_buffer(o, r->server_name);
79 } else
80 /* Lookup name: secondly try to get hostname for bind address */
81 if (0 != sock_addr_nameinfo_append_buffer(o, &our_addr, r->conf.errh)) {
82 r->http_status = 500;
83 return -1;
84 }
85
86 {
87 unsigned short listen_port = sock_addr_get_port(&our_addr);
88 unsigned short default_port = 80;
89 if (buffer_is_equal_string(&r->uri.scheme, CONST_STR_LEN("https"))) {
90 default_port = 443;
91 }
92 if (0 == listen_port) listen_port = r->con->srv->srvconf.port;
93 if (default_port != listen_port) {
94 buffer_append_string_len(o, CONST_STR_LEN(":"));
95 buffer_append_int(o, listen_port);
96 }
97 }
98 }
99 return 0;
100 }
101
http_response_redirect_to_directory(request_st * const r,int status)102 int http_response_redirect_to_directory(request_st * const r, int status) {
103 buffer *o = r->tmp_buf;
104 buffer_clear(o);
105 /* XXX: store flag in global at startup? */
106 if (r->con->srv->srvconf.absolute_dir_redirect) {
107 buffer_append_str2(o, BUF_PTR_LEN(&r->uri.scheme),
108 CONST_STR_LEN("://"));
109 if (0 != http_response_buffer_append_authority(r, o)) {
110 return -1;
111 }
112 }
113 buffer *vb;
114 if (status >= 300) {
115 r->http_status = status;
116 r->resp_body_finished = 1;
117 vb = http_header_response_set_ptr(r, HTTP_HEADER_LOCATION,
118 CONST_STR_LEN("Location"));
119 }
120 else {
121 vb = http_header_response_set_ptr(r, HTTP_HEADER_CONTENT_LOCATION,
122 CONST_STR_LEN("Content-Location"));
123 }
124 buffer_copy_buffer(vb, o);
125 buffer_append_string_encoded(vb, BUF_PTR_LEN(&r->uri.path),
126 ENCODING_REL_URI);
127 buffer_append_string_len(vb, CONST_STR_LEN("/"));
128 if (!buffer_is_blank(&r->uri.query))
129 buffer_append_str2(vb, CONST_STR_LEN("?"),
130 BUF_PTR_LEN(&r->uri.query));
131
132 return 0;
133 }
134
135 #define MTIME_CACHE_MAX 16
136 struct mtime_cache_type {
137 unix_time64_t mtime; /* key */
138 buffer str; /* buffer for string representation */
139 };
140 static struct mtime_cache_type mtime_cache[MTIME_CACHE_MAX];
141 static char mtime_cache_str[MTIME_CACHE_MAX][HTTP_DATE_SZ];
142 /* 30-chars for "%a, %d %b %Y %T GMT" */
143
strftime_cache_reset(void)144 void strftime_cache_reset(void) {
145 for (int i = 0; i < MTIME_CACHE_MAX; ++i) {
146 mtime_cache[i].mtime = -1;
147 mtime_cache[i].str.ptr = mtime_cache_str[i];
148 mtime_cache[i].str.used = sizeof(mtime_cache_str[0]);
149 mtime_cache[i].str.size = sizeof(mtime_cache_str[0]);
150 }
151 }
152
strftime_cache_get(const unix_time64_t last_mod)153 static const buffer * strftime_cache_get(const unix_time64_t last_mod) {
154 /*(note: not bothering to convert *here* if last_mod < 0 (for cache key);
155 * last_mod < 0 handled in http_date_time_to_str() call to gmtime64_r())*/
156
157 static int mtime_cache_idx;
158
159 for (int j = 0; j < MTIME_CACHE_MAX; ++j) {
160 if (mtime_cache[j].mtime == last_mod)
161 return &mtime_cache[j].str; /* found cache-entry */
162 }
163
164 if (++mtime_cache_idx == MTIME_CACHE_MAX) mtime_cache_idx = 0;
165
166 const int i = mtime_cache_idx;
167 http_date_time_to_str(mtime_cache[i].str.ptr, sizeof(mtime_cache_str[0]),
168 (mtime_cache[i].mtime = last_mod));
169
170 return &mtime_cache[i].str;
171 }
172
173
http_response_set_last_modified(request_st * const r,const unix_time64_t lmtime)174 const buffer * http_response_set_last_modified(request_st * const r, const unix_time64_t lmtime) {
175 buffer * const vb =
176 http_header_response_set_ptr(r, HTTP_HEADER_LAST_MODIFIED,
177 CONST_STR_LEN("Last-Modified"));
178 buffer_copy_buffer(vb, strftime_cache_get(lmtime));
179 return vb;
180 }
181
182
http_response_handle_cachable(request_st * const r,const buffer * const lmod,const unix_time64_t lmtime)183 int http_response_handle_cachable(request_st * const r, const buffer * const lmod, const unix_time64_t lmtime) {
184 if (!(r->rqst_htags
185 & (light_bshift(HTTP_HEADER_IF_NONE_MATCH)
186 |light_bshift(HTTP_HEADER_IF_MODIFIED_SINCE)))) {
187 return HANDLER_GO_ON;
188 }
189
190 const buffer *vb;
191
192 /*
193 * 14.26 If-None-Match
194 * [...]
195 * If none of the entity tags match, then the server MAY perform the
196 * requested method as if the If-None-Match header field did not exist,
197 * but MUST also ignore any If-Modified-Since header field(s) in the
198 * request. That is, if no entity tags match, then the server MUST NOT
199 * return a 304 (Not Modified) response.
200 */
201
202 if ((vb = http_header_request_get(r, HTTP_HEADER_IF_NONE_MATCH,
203 CONST_STR_LEN("If-None-Match")))) {
204 /*(weak etag comparison must not be used for ranged requests)*/
205 int range_request = (0 != light_btst(r->rqst_htags, HTTP_HEADER_RANGE));
206 if (http_etag_matches(&r->physical.etag, vb->ptr, !range_request)) {
207 if (http_method_get_or_head(r->http_method)) {
208 r->http_status = 304;
209 return HANDLER_FINISHED;
210 } else {
211 r->http_status = 412;
212 r->handler_module = NULL;
213 return HANDLER_FINISHED;
214 }
215 }
216 } else if (http_method_get_or_head(r->http_method)
217 && (vb = http_header_request_get(r, HTTP_HEADER_IF_MODIFIED_SINCE,
218 CONST_STR_LEN("If-Modified-Since")))) {
219 /* last-modified handling */
220 if (buffer_is_equal(lmod, vb)
221 || !http_date_if_modified_since(BUF_PTR_LEN(vb), lmtime)) {
222 r->http_status = 304;
223 return HANDLER_FINISHED;
224 }
225 }
226
227 return HANDLER_GO_ON;
228 }
229
230
http_response_body_clear(request_st * const r,int preserve_length)231 void http_response_body_clear (request_st * const r, int preserve_length) {
232 r->resp_send_chunked = 0;
233 r->resp_body_scratchpad = -1;
234 if (light_btst(r->resp_htags, HTTP_HEADER_TRANSFER_ENCODING)) {
235 http_header_response_unset(r, HTTP_HEADER_TRANSFER_ENCODING,
236 CONST_STR_LEN("Transfer-Encoding"));
237 }
238 if (!preserve_length) { /* preserve for HEAD responses and no-content responses (204, 205, 304) */
239 if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
240 http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
241 CONST_STR_LEN("Content-Length"));
242 }
243 /*(if not preserving Content-Length, do not preserve trailers, if any)*/
244 r->resp_decode_chunked = 0;
245 if (r->gw_dechunk) {
246 free(r->gw_dechunk->b.ptr);
247 free(r->gw_dechunk);
248 r->gw_dechunk = NULL;
249 }
250 }
251 chunkqueue_reset(&r->write_queue);
252 }
253
254
http_response_header_clear(request_st * const r)255 static void http_response_header_clear (request_st * const r) {
256 r->http_status = 0;
257 r->resp_htags = 0;
258 r->resp_header_len = 0;
259 r->resp_header_repeated = 0;
260 array_reset_data_strings(&r->resp_headers);
261
262 /* Note: http_response_body_clear(r, 0) is not called here
263 * r->write_queue should be preserved for additional data after 1xx response
264 * However, if http_response_process_headers() was called and response had
265 * Transfer-Encoding: chunked set, then other items need to be reset */
266 r->resp_send_chunked = 0;
267 r->resp_decode_chunked = 0;
268 r->resp_body_scratchpad = -1;
269 if (r->gw_dechunk) {
270 free(r->gw_dechunk->b.ptr);
271 free(r->gw_dechunk);
272 r->gw_dechunk = NULL;
273 }
274 }
275
276
http_response_reset(request_st * const r)277 void http_response_reset (request_st * const r) {
278 r->http_status = 0;
279 r->con->is_writable = 1;
280 r->resp_body_finished = 0;
281 r->resp_body_started = 0;
282 r->handler_module = NULL;
283 if (r->physical.path.ptr) { /*(skip for mod_fastcgi authorizer)*/
284 buffer_clear(&r->physical.doc_root);
285 buffer_clear(&r->physical.basedir);
286 buffer_clear(&r->physical.etag);
287 buffer_reset(&r->physical.path);
288 buffer_reset(&r->physical.rel_path);
289 }
290 r->resp_htags = 0;
291 r->resp_header_len = 0;
292 r->resp_header_repeated = 0;
293 array_reset_data_strings(&r->resp_headers);
294 http_response_body_clear(r, 0);
295 }
296
297
http_response_reqbody_read_error(request_st * const r,int http_status)298 handler_t http_response_reqbody_read_error (request_st * const r, int http_status) {
299 r->keep_alive = 0;
300
301 /*(do not change status if response headers already set and possibly sent)*/
302 if (0 != r->resp_header_len) return HANDLER_ERROR;
303
304 http_response_body_clear(r, 0);
305 r->http_status = http_status;
306 r->handler_module = NULL;
307 return HANDLER_FINISHED;
308 }
309
310
http_response_send_file(request_st * const r,buffer * const path,stat_cache_entry * sce)311 void http_response_send_file (request_st * const r, buffer * const path, stat_cache_entry *sce) {
312 if (NULL == sce
313 || (sce->fd < 0 && __builtin_expect( (0 != sce->st.st_size), 0))) {
314 sce = stat_cache_get_entry_open(path, r->conf.follow_symlink);
315 if (NULL == sce) {
316 r->http_status = (errno == ENOENT) ? 404 : 403;
317 log_error(r->conf.errh, __FILE__, __LINE__,
318 "not a regular file: %s -> %s", r->uri.path.ptr, path->ptr);
319 return;
320 }
321 if (sce->fd < 0 && __builtin_expect( (0 != sce->st.st_size), 0)) {
322 r->http_status = (errno == ENOENT) ? 404 : 403;
323 if (r->conf.log_request_handling) {
324 log_perror(r->conf.errh, __FILE__, __LINE__,
325 "file open failed: %s", path->ptr);
326 }
327 return;
328 }
329 }
330
331 if (__builtin_expect( (!r->conf.follow_symlink), 0)
332 && 0 != stat_cache_path_contains_symlink(path, r->conf.errh)) {
333 r->http_status = 403;
334 if (r->conf.log_request_handling) {
335 log_error(r->conf.errh, __FILE__, __LINE__,
336 "-- access denied due symlink restriction");
337 log_error(r->conf.errh, __FILE__, __LINE__,
338 "Path : %s", path->ptr);
339 }
340 return;
341 }
342
343 /* we only handle regular files */
344 if (__builtin_expect( (!S_ISREG(sce->st.st_mode)), 0)) {
345 r->http_status = 403;
346 if (r->conf.log_file_not_found) {
347 log_error(r->conf.errh, __FILE__, __LINE__,
348 "not a regular file: %s -> %s",
349 r->uri.path.ptr, path->ptr);
350 }
351 return;
352 }
353
354 int allow_caching = (0 == r->http_status || 200 == r->http_status);
355
356 /* set response content-type, if not set already */
357
358 if (!light_btst(r->resp_htags, HTTP_HEADER_CONTENT_TYPE)) {
359 const buffer *content_type = stat_cache_content_type_get(sce, r);
360 if (content_type && !buffer_is_blank(content_type)) {
361 http_header_response_set(r, HTTP_HEADER_CONTENT_TYPE,
362 CONST_STR_LEN("Content-Type"),
363 BUF_PTR_LEN(content_type));
364 } else {
365 /* we are setting application/octet-stream, but also announce that
366 * this header field might change in the seconds few requests
367 *
368 * This should fix the aggressive caching of FF and the script download
369 * seen by the first installations
370 */
371 http_header_response_set(r, HTTP_HEADER_CONTENT_TYPE,
372 CONST_STR_LEN("Content-Type"),
373 CONST_STR_LEN("application/octet-stream"));
374
375 allow_caching = 0;
376 }
377 }
378
379 if (allow_caching) {
380 if (!light_btst(r->resp_htags, HTTP_HEADER_ETAG)
381 && 0 != r->conf.etag_flags) {
382 const buffer *etag =
383 stat_cache_etag_get(sce, r->conf.etag_flags);
384 if (etag && !buffer_is_blank(etag)) {
385 buffer_copy_buffer(&r->physical.etag, etag);
386 http_header_response_set(r, HTTP_HEADER_ETAG,
387 CONST_STR_LEN("ETag"),
388 BUF_PTR_LEN(&r->physical.etag));
389 }
390 }
391
392 /* prepare header */
393 const buffer *mtime;
394 mtime = http_header_response_get(r, HTTP_HEADER_LAST_MODIFIED,
395 CONST_STR_LEN("Last-Modified"));
396 if (NULL == mtime) {
397 mtime = http_response_set_last_modified(r, sce->st.st_mtime);
398 }
399
400 if (HANDLER_FINISHED == http_response_handle_cachable(r, mtime, sce->st.st_mtime)) {
401 return;
402 }
403 }
404
405 /* if we are still here, prepare body */
406
407 /* we add it here for all requests
408 * the HEAD request will drop it afterwards again
409 */
410
411 if (0 == sce->st.st_size || 0 == http_chunk_append_file_ref(r, sce)) {
412 r->http_status = 200;
413 r->resp_body_finished = 1;
414 /*(Transfer-Encoding should not have been set at this point)*/
415 buffer_append_int(
416 http_header_response_set_ptr(r, HTTP_HEADER_CONTENT_LENGTH,
417 CONST_STR_LEN("Content-Length")),
418 sce->st.st_size);
419 }
420 else {
421 r->http_status = 500;
422 }
423 }
424
425
http_response_xsendfile(request_st * const r,buffer * const path,const array * const xdocroot)426 static void http_response_xsendfile (request_st * const r, buffer * const path, const array * const xdocroot) {
427 const int status = r->http_status;
428 int valid = 1;
429
430 /* reset Content-Length, if set by backend
431 * Content-Length might later be set to size of X-Sendfile static file,
432 * determined by open(), fstat() to reduces race conditions if the file
433 * is modified between stat() (stat_cache_get_entry()) and open(). */
434 if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
435 http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
436 CONST_STR_LEN("Content-Length"));
437 }
438
439 buffer_urldecode_path(path);
440 if (!buffer_is_valid_UTF8(path)) {
441 log_error(r->conf.errh, __FILE__, __LINE__,
442 "X-Sendfile invalid UTF-8 after url-decode: %s", path->ptr);
443 if (r->http_status < 400) {
444 r->http_status = 502;
445 r->handler_module = NULL;
446 }
447 return;
448 }
449 buffer_path_simplify(path);
450 if (r->conf.force_lowercase_filenames) {
451 buffer_to_lower(path);
452 }
453 if (buffer_is_blank(path)) {
454 r->http_status = 502;
455 valid = 0;
456 }
457
458 /* check that path is under xdocroot(s)
459 * - xdocroot should have trailing slash appended at config time
460 * - r->conf.force_lowercase_filenames is not a server-wide setting,
461 * and so can not be definitively applied to xdocroot at config time*/
462 if (xdocroot && xdocroot->used) {
463 const buffer * const xval = !r->conf.force_lowercase_filenames
464 ? array_match_value_prefix(xdocroot, path)
465 : array_match_value_prefix_nc(xdocroot, path);
466 if (NULL == xval) {
467 log_error(r->conf.errh, __FILE__, __LINE__,
468 "X-Sendfile (%s) not under configured x-sendfile-docroot(s)", path->ptr);
469 r->http_status = 403;
470 valid = 0;
471 }
472 }
473
474 if (valid) http_response_send_file(r, path, NULL);
475
476 if (r->http_status >= 400 && status < 300) {
477 r->handler_module = NULL;
478 } else if (0 != status && 200 != status) {
479 r->http_status = status;
480 }
481 }
482
483
http_response_xsendfile2(request_st * const r,const buffer * const value,const array * const xdocroot)484 static void http_response_xsendfile2(request_st * const r, const buffer * const value, const array * const xdocroot) {
485 const char *pos = value->ptr;
486 buffer * const b = r->tmp_buf;
487 const int status = r->http_status;
488
489 /* reset Content-Length, if set by backend */
490 if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
491 http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
492 CONST_STR_LEN("Content-Length"));
493 }
494
495 while (*pos) {
496 const char *filename, *range;
497 stat_cache_entry *sce;
498 off_t begin_range, end_range, range_len;
499
500 while (' ' == *pos) pos++;
501 if (!*pos) break;
502
503 filename = pos;
504 if (NULL == (range = strchr(pos, ' '))) {
505 /* missing range */
506 log_error(r->conf.errh, __FILE__, __LINE__,
507 "Couldn't find range after filename: %s", filename);
508 r->http_status = 502;
509 break;
510 }
511 buffer_copy_string_len(b, filename, range - filename);
512
513 /* find end of range */
514 for (pos = ++range; *pos && *pos != ' ' && *pos != ','; pos++) ;
515
516 buffer_urldecode_path(b);
517 if (!buffer_is_valid_UTF8(b)) {
518 log_error(r->conf.errh, __FILE__, __LINE__,
519 "X-Sendfile2 invalid UTF-8 after url-decode: %s", b->ptr);
520 r->http_status = 502;
521 break;
522 }
523 buffer_path_simplify(b);
524 if (r->conf.force_lowercase_filenames) {
525 buffer_to_lower(b);
526 }
527 if (buffer_is_blank(b)) {
528 r->http_status = 502;
529 break;
530 }
531 if (xdocroot && xdocroot->used) {
532 const buffer * const xval = !r->conf.force_lowercase_filenames
533 ? array_match_value_prefix(xdocroot, b)
534 : array_match_value_prefix_nc(xdocroot, b);
535 if (NULL == xval) {
536 log_error(r->conf.errh, __FILE__, __LINE__,
537 "X-Sendfile2 (%s) not under configured x-sendfile-docroot(s)",
538 b->ptr);
539 r->http_status = 403;
540 break;
541 }
542 }
543
544 sce = stat_cache_get_entry_open(b, r->conf.follow_symlink);
545 if (NULL == sce) {
546 log_error(r->conf.errh, __FILE__, __LINE__,
547 "send-file error: couldn't get stat_cache entry for "
548 "X-Sendfile2: %s", b->ptr);
549 r->http_status = 404;
550 break;
551 } else if (!S_ISREG(sce->st.st_mode)) {
552 log_error(r->conf.errh, __FILE__, __LINE__,
553 "send-file error: wrong filetype for X-Sendfile2: %s", b->ptr);
554 r->http_status = 502;
555 break;
556 }
557 /* found the file */
558
559 /* parse range */
560 end_range = sce->st.st_size - 1;
561 {
562 char *rpos = NULL;
563 errno = 0;
564 begin_range = strtoll(range, &rpos, 10);
565 if (errno != 0 || begin_range < 0 || rpos == range)
566 goto range_failed;
567 if ('-' != *rpos++) goto range_failed;
568 if (rpos != pos) {
569 range = rpos;
570 end_range = strtoll(range, &rpos, 10);
571 if (errno != 0 || end_range < 0 || rpos == range)
572 goto range_failed;
573 }
574 if (rpos != pos) goto range_failed;
575
576 goto range_success;
577
578 range_failed:
579 log_error(r->conf.errh, __FILE__, __LINE__,
580 "Couldn't decode range after filename: %s", filename);
581 r->http_status = 502;
582 break;
583
584 range_success: ;
585 }
586
587 /* no parameters accepted */
588
589 while (*pos == ' ') pos++;
590 if (*pos != '\0' && *pos != ',') {
591 r->http_status = 502;
592 break;
593 }
594
595 range_len = end_range - begin_range + 1;
596 if (range_len < 0) {
597 r->http_status = 502;
598 break;
599 }
600 if (range_len != 0) {
601 http_chunk_append_file_ref_range(r, sce, begin_range, range_len);
602 }
603
604 if (*pos == ',') pos++;
605 }
606
607 if (r->http_status >= 400 && status < 300) {
608 r->handler_module = NULL;
609 } else if (0 != status && 200 != status) {
610 r->http_status = status;
611 }
612 }
613
614
http_response_backend_error(request_st * const r)615 void http_response_backend_error (request_st * const r) {
616 if (r->resp_body_started) {
617 /*(response might have been already started, kill the connection)*/
618 /*(mode == DIRECT to avoid later call to http_response_backend_done())*/
619 r->handler_module = NULL; /*(avoid sending final chunked block)*/
620 r->keep_alive = 0;
621 r->resp_body_finished = 1;
622 } /*(else error status set later by http_response_backend_done())*/
623 }
624
http_response_backend_done(request_st * const r)625 void http_response_backend_done (request_st * const r) {
626 /* (not CON_STATE_ERROR and not CON_STATE_RESPONSE_END,
627 * i.e. not called from handle_connection_close or handle_request_reset
628 * hooks, except maybe from errdoc handler, which later resets state)*/
629 switch (r->state) {
630 case CON_STATE_HANDLE_REQUEST:
631 case CON_STATE_READ_POST:
632 if (!r->resp_body_started) {
633 /* Send an error if we haven't sent any data yet */
634 if (r->http_status < 500 && r->http_status != 400)
635 r->http_status = 500;
636 r->handler_module = NULL;
637 break;
638 }
639 __attribute_fallthrough__
640 case CON_STATE_WRITE:
641 if (!r->resp_body_finished) {
642 if (r->http_version == HTTP_VERSION_1_1)
643 http_chunk_close(r);
644 #if 0
645 /* This is a lot of work to make it possible for an HTTP/1.0 client
646 * to detect that response is truncated (after lighttpd made an
647 * HTTP/1.1 request to backend, and backend gave a Transfer-Encoding
648 * chunked response instead of sending Content-Length, and lighttpd
649 * is streaming response to client). An HTTP/1.0 client is probably
650 * not checking for truncated response, or else client should really
651 * prefer HTTP/1.1 or better. If lighttpd were streaming response,
652 * there would be no Content-Length and lighttpd would have sent
653 * Connection: close. Alternatively, since not streaming (if these
654 * conditions are true), could send an HTTP status error instead of
655 * sending partial content with a bogus Content-Length. If we do
656 * not send an HTTP error status, then response_start hooks may add
657 * caching headers (e.g. mod_expire, mod_setenv). If in future we
658 * send HTTP error status, might special-case HEAD requests and
659 * clear response body so that response headers (w/o Content-Length)
660 * can be sent. For now, we have chosen to send partial content,
661 * including generating an incorrect Content-Length (later), and not
662 * to take any of these extra steps. */
663 else if (__builtin_expect( (r->http_version == HTTP_VERSION_1_0), 0)
664 && r->gw_dechunk && !r->gw_dechunk->done
665 && !(r->conf.stream_response_body
666 & (FDEVENT_STREAM_RESPONSE
667 |FDEVENT_STREAM_RESPONSE_BUFMIN))) {
668 r->keep_alive = 0; /* disable keep-alive, send bogus length */
669 http_header_response_set(r, HTTP_HEADER_CONTENT_LENGTH,
670 CONST_STR_LEN("Content-Length"),
671 CONST_STR_LEN("9999999999999"));
672 http_header_response_unset(r, HTTP_HEADER_ETAG,
673 CONST_STR_LEN("ETag"));
674 http_header_response_unset(r, HTTP_HEADER_LAST_MODIFIED,
675 CONST_STR_LEN("Last-Modified"));
676 http_header_response_unset(r, HTTP_HEADER_CACHE_CONTROL,
677 CONST_STR_LEN("Cache-Control"));
678 http_header_response_unset(r, HTTP_HEADER_EXPIRES,
679 CONST_STR_LEN("Expires"));
680 }
681 #endif
682 r->resp_body_finished = 1;
683 }
684 default:
685 break;
686 }
687 }
688
689
http_response_upgrade_read_body_unknown(request_st * const r)690 void http_response_upgrade_read_body_unknown(request_st * const r) {
691 /* act as transparent proxy */
692 if (!(r->conf.stream_request_body & FDEVENT_STREAM_REQUEST))
693 r->conf.stream_request_body |=
694 (FDEVENT_STREAM_REQUEST_BUFMIN | FDEVENT_STREAM_REQUEST);
695 if (!(r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE))
696 r->conf.stream_response_body |=
697 (FDEVENT_STREAM_RESPONSE_BUFMIN | FDEVENT_STREAM_RESPONSE);
698 r->conf.stream_request_body |= FDEVENT_STREAM_REQUEST_POLLIN;
699 r->reqbody_length = -2;
700 r->resp_body_scratchpad = -1;
701 r->keep_alive = 0;
702 }
703
704
705 __attribute_pure__
http_response_append_buffer_simple_accum(const request_st * const r,const off_t len)706 static int http_response_append_buffer_simple_accum(const request_st * const r, const off_t len) {
707 /*(check to accumulate small reads in buffer before flushing to temp file)*/
708 return
709 len < 32768 && r->write_queue.last && r->write_queue.last->file.is_temp;
710 }
711
712
http_response_append_buffer(request_st * const r,buffer * const mem,const int simple_accum)713 static int http_response_append_buffer(request_st * const r, buffer * const mem, const int simple_accum) {
714 /* Note: this routine is separate from http_response_append_mem() to
715 * potentially avoid copying buffer by using http_chunk_append_buffer(). */
716
717 if (r->resp_decode_chunked)
718 return http_chunk_decode_append_buffer(r, mem);
719
720 if (r->resp_body_scratchpad > 0) {
721 off_t len = (off_t)buffer_clen(mem);
722 r->resp_body_scratchpad -= len;
723 if (r->resp_body_scratchpad > 0) {
724 if (simple_accum
725 && http_response_append_buffer_simple_accum(r, len)) {
726 r->resp_body_scratchpad += len;
727 return 0; /*(accumulate small reads in buffer)*/
728 }
729 }
730 else { /* (r->resp_body_scratchpad <= 0) */
731 r->resp_body_finished = 1;
732 if (__builtin_expect( (r->resp_body_scratchpad < 0), 0)) {
733 /*(silently truncate if data exceeds Content-Length)*/
734 len += r->resp_body_scratchpad;
735 r->resp_body_scratchpad = 0;
736 buffer_truncate(mem, (uint32_t)len);
737 }
738 }
739 }
740 else if (0 == r->resp_body_scratchpad) {
741 /*(silently truncate if data exceeds Content-Length)*/
742 buffer_clear(mem);
743 return 0;
744 }
745 else if (simple_accum
746 && http_response_append_buffer_simple_accum(r, buffer_clen(mem))) {
747 return 0; /*(accumulate small reads in buffer)*/
748 }
749 return http_chunk_append_buffer(r, mem);
750 }
751
752
753 #ifdef HAVE_SPLICE
http_response_append_splice(request_st * const r,http_response_opts * const opts,buffer * const b,const int fd,unsigned int toread)754 static int http_response_append_splice(request_st * const r, http_response_opts * const opts, buffer * const b, const int fd, unsigned int toread) {
755 /* check if worthwhile to splice() to avoid copying through userspace */
756 /*assert(opts->simple_accum);*//*(checked in caller)*/
757 if (r->resp_body_scratchpad >= toread
758 && (toread > 32768
759 || (toread >= 8192 /*(!http_response_append_buffer_simple_accum())*/
760 && r->write_queue.last && r->write_queue.last->file.is_temp))) {
761
762 if (!buffer_is_blank(b)) {
763 /*(flush small reads previously accumulated in b)*/
764 int rc = http_response_append_buffer(r, b, 0); /*(0 to flush)*/
765 chunk_buffer_yield(b); /*(improve large buf reuse)*/
766 if (__builtin_expect( (0 != rc), 0)) return -1; /* error */
767 }
768
769 /*assert(opts->fdfmt == S_IFSOCK || opts->fdfmt == S_IFIFO);*/
770 ssize_t n = (opts->fdfmt == S_IFSOCK)
771 ? chunkqueue_append_splice_sock_tempfile(
772 &r->write_queue, fd, toread, r->conf.errh)
773 : chunkqueue_append_splice_pipe_tempfile(
774 &r->write_queue, fd, toread, r->conf.errh);
775 if (__builtin_expect( (n >= 0), 1)) {
776 if (0 == (r->resp_body_scratchpad -= n))
777 r->resp_body_finished = 1;
778 return 1; /* success */
779 }
780 else if (n != -EINVAL)
781 return -1; /* error */
782 /*(fall through; target filesystem w/o splice() support)*/
783 }
784 return 0; /* not handled */
785 }
786 #endif
787
788
http_response_append_mem(request_st * const r,const char * const mem,size_t len)789 static int http_response_append_mem(request_st * const r, const char * const mem, size_t len) {
790 if (r->resp_decode_chunked)
791 return http_chunk_decode_append_mem(r, mem, len);
792
793 if (r->resp_body_scratchpad > 0) {
794 r->resp_body_scratchpad -= (off_t)len;
795 if (r->resp_body_scratchpad <= 0) {
796 r->resp_body_finished = 1;
797 if (__builtin_expect( (r->resp_body_scratchpad < 0), 0)) {
798 /*(silently truncate if data exceeds Content-Length)*/
799 len = (size_t)(r->resp_body_scratchpad + (off_t)len);
800 r->resp_body_scratchpad = 0;
801 }
802 }
803 }
804 else if (0 == r->resp_body_scratchpad) {
805 /*(silently truncate if data exceeds Content-Length)*/
806 return 0;
807 }
808 return http_chunk_append_mem(r, mem, len);
809 }
810
811
http_response_transfer_cqlen(request_st * const r,chunkqueue * const cq,size_t len)812 int http_response_transfer_cqlen(request_st * const r, chunkqueue * const cq, size_t len) {
813 /*(intended for use as callback from modules setting opts->parse(),
814 * e.g. mod_fastcgi and mod_ajp13)
815 *(do not set r->resp_body_finished here since those protocols handle it)*/
816 if (0 == len) return 0;
817 if (__builtin_expect( (!r->resp_decode_chunked), 1)) {
818 const size_t olen = len;
819 if (r->resp_body_scratchpad >= 0) {
820 r->resp_body_scratchpad -= (off_t)len;
821 if (__builtin_expect( (r->resp_body_scratchpad < 0), 0)) {
822 /*(silently truncate if data exceeds Content-Length)*/
823 len = (size_t)(r->resp_body_scratchpad + (off_t)len);
824 r->resp_body_scratchpad = 0;
825 }
826 }
827 int rc = http_chunk_transfer_cqlen(r, cq, len);
828 if (__builtin_expect( (0 != rc), 0))
829 return -1;
830 if (__builtin_expect( (olen != len), 0)) /*discard excess data, if any*/
831 chunkqueue_mark_written(cq, (off_t)(olen - len));
832 }
833 else {
834 /* specialized use by opts->parse() to decode chunked encoding;
835 * FastCGI, AJP13 packet data is all type MEM_CHUNK
836 * (This extra copy can be avoided if FastCGI backend does not send
837 * Transfer-Encoding: chunked, which FastCGI is not supposed to do) */
838 uint32_t remain = (uint32_t)len, wr;
839 for (const chunk *c = cq->first; c && remain; c=c->next, remain-=wr) {
840 /*assert(c->type == MEM_CHUNK);*/
841 wr = buffer_clen(c->mem) - c->offset;
842 if (wr > remain) wr = remain;
843 if (0 != http_chunk_decode_append_mem(r, c->mem->ptr+c->offset, wr))
844 return -1;
845 }
846 chunkqueue_mark_written(cq, len);
847 }
848 return 0;
849 }
850
851
http_response_process_headers(request_st * const restrict r,http_response_opts * const restrict opts,char * const restrict s,const unsigned short hoff[8192],const int is_nph)852 static int http_response_process_headers(request_st * const restrict r, http_response_opts * const restrict opts, char * const restrict s, const unsigned short hoff[8192], const int is_nph) {
853 int i = 1;
854
855 if (is_nph) {
856 /* non-parsed headers ... we parse them anyway */
857 /* (accept HTTP/2.0 and HTTP/3.0 from naive non-proxy backends) */
858 /* (http_header_str_to_code() expects certain chars after code) */
859 if (s[12] == '\r' || s[12] == '\n') s[12] = '\0';/*(caller checked 12)*/
860 if ((s[5] == '1' || opts->backend != BACKEND_PROXY) && s[6] == '.'
861 && (s[7] == '1' || s[7] == '0') && s[8] == ' ') {
862 /* after the space should be a status code for us */
863 int status = http_header_str_to_code(s+9);
864 if (status >= 100 && status < 1000) {
865 #ifdef __COVERITY__ /* Coverity false positive for tainted data */
866 status = 200;/* http_header_str_to_code() validates, untaints */
867 #endif
868 r->http_status = status;
869 opts->local_redir = 0; /*(disable; status was set)*/
870 i = 2;
871 } /* else we expected 3 digits and didn't get them */
872 }
873
874 if (0 == r->http_status) {
875 log_error(r->conf.errh, __FILE__, __LINE__,
876 "invalid HTTP status line: %s", s);
877 r->http_status = 502; /* Bad Gateway */
878 r->handler_module = NULL;
879 return 0;
880 }
881 }
882 else if (__builtin_expect( (opts->backend == BACKEND_PROXY), 0)) {
883 /* invalid response Status-Line from HTTP proxy */
884 r->http_status = 502; /* Bad Gateway */
885 r->handler_module = NULL;
886 return 0;
887 }
888
889 for (; i < hoff[0]; ++i) {
890 const char *k = s+hoff[i], *value;
891 char *end = s+hoff[i+1]-1; /*('\n')*/
892
893 /* parse the headers */
894 if (NULL == (value = memchr(k, ':', end - k))) {
895 /* we expect: "<key>: <value>\r\n" */
896 continue;
897 }
898
899 const uint32_t klen = (uint32_t)(value - k);
900 if (0 == klen) continue; /*(already ignored when writing response)*/
901 const enum http_header_e id = http_header_hkey_get(k, klen);
902
903 do { ++value; } while (*value == ' ' || *value == '\t'); /* skip LWS */
904 /* strip the \r?\n */
905 if (end > value && end[-1] == '\r') --end;
906 /*(XXX: not done; could remove trailing whitespace)*/
907
908 if (opts->authorizer && (0 == r->http_status || 200 == r->http_status)){
909 if (id == HTTP_HEADER_STATUS) {
910 end[0] = '\0';
911 int status = http_header_str_to_code(value);
912 if (status >= 100 && status < 1000) {
913 #ifdef __COVERITY__ /* Coverity false positive for tainted */
914 status = 200;/* http_header_str_to_code() validates */
915 #endif
916 r->http_status = status;
917 opts->local_redir = 0; /*(disable; status was set)*/
918 }
919 else {
920 r->http_status = 502; /* Bad Gateway */
921 break; /*(do not unset r->handler_module)*/
922 }
923 }
924 else if (id == HTTP_HEADER_OTHER && klen > 9 && (k[0] & 0xdf) == 'V'
925 && buffer_eq_icase_ssn(k, CONST_STR_LEN("Variable-"))) {
926 http_header_env_append(r, k + 9, klen - 9, value, end - value);
927 }
928 continue;
929 }
930
931 switch (id) {
932 case HTTP_HEADER_STATUS:
933 if (opts->backend != BACKEND_PROXY) {
934 end[0] = '\0';
935 int status = http_header_str_to_code(value);
936 if (status >= 100 && status < 1000) {
937 #ifdef __COVERITY__ /* Coverity false positive for tainted */
938 status = 200;/* http_header_str_to_code() validates */
939 #endif
940 r->http_status = status;
941 opts->local_redir = 0; /*(disable; status was set)*/
942 }
943 else {
944 r->http_status = 502;
945 r->handler_module = NULL;
946 }
947 continue; /* do not send Status to client */
948 } /*(else pass w/o parse for BACKEND_PROXY)*/
949 break;
950 case HTTP_HEADER_UPGRADE:
951 /*(technically, should also verify Connection: upgrade)*/
952 /*(flag only for mod_proxy and mod_cgi (for now))*/
953 if (opts->backend != BACKEND_PROXY && opts->backend != BACKEND_CGI)
954 continue;
955 if (r->http_version >= HTTP_VERSION_2) continue;
956 break;
957 case HTTP_HEADER_CONNECTION:
958 if (opts->backend == BACKEND_PROXY) continue;
959 /*(simplistic attempt to honor backend request to close)*/
960 if (http_header_str_contains_token(value, end - value,
961 CONST_STR_LEN("close")))
962 r->keep_alive = 0;
963 if (r->http_version >= HTTP_VERSION_2) continue;
964 break;
965 case HTTP_HEADER_CONTENT_LENGTH:
966 if (*value == '+') ++value;
967 if (!r->resp_decode_chunked
968 && !light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
969 const char *err = end;
970 while (err > value && (err[-1] == ' ' || err[-1] == '\t')) --err;
971 if (err <= value) continue; /*(might error 502 Bad Gateway)*/
972 uint32_t vlen = (uint32_t)(err - value);
973 r->resp_body_scratchpad =
974 (off_t)li_restricted_strtoint64(value, vlen, &err);
975 if (err != value + vlen) {
976 /*(invalid Content-Length value from backend;
977 * read from backend until backend close, hope for the best)
978 *(might choose to treat this as 502 Bad Gateway) */
979 r->resp_body_scratchpad = -1;
980 }
981 }
982 else {
983 /* ignore Content-Length if Transfer-Encoding: chunked
984 * ignore subsequent (multiple) Content-Length
985 * (might choose to treat this as 502 Bad Gateway) */
986 continue;
987 }
988 break;
989 case HTTP_HEADER_TRANSFER_ENCODING:
990 if (light_btst(r->resp_htags, HTTP_HEADER_CONTENT_LENGTH)) {
991 /* ignore Content-Length if Transfer-Encoding: chunked
992 * (might choose to treat this as 502 Bad Gateway) */
993 r->resp_body_scratchpad = -1;
994 http_header_response_unset(r, HTTP_HEADER_CONTENT_LENGTH,
995 CONST_STR_LEN("Content-Length"));
996 }
997 /*(assumes "Transfer-Encoding: chunked"; does not verify)*/
998 r->resp_decode_chunked = 1;
999 r->gw_dechunk = calloc(1, sizeof(response_dechunk));
1000 force_assert(r->gw_dechunk);
1001 continue;
1002 case HTTP_HEADER_HTTP2_SETTINGS:
1003 /* RFC7540 3.2.1
1004 * A server MUST NOT send this header field. */
1005 /* (not bothering to remove HTTP2-Settings from Connection) */
1006 continue;
1007 case HTTP_HEADER_OTHER:
1008 /* ignore invalid headers with whitespace between label and ':'
1009 * (if less strict behavior is desired, check and correct above
1010 * this switch() statement, but not for BACKEND_PROXY) */
1011 if (k[klen-1] == ' ' || k[klen-1] == '\t')
1012 continue;
1013 break;
1014 default:
1015 break;
1016 }
1017
1018 if (end - value)
1019 http_header_response_insert(r, id, k, klen, value, end - value);
1020 }
1021
1022 /* CGI/1.1 rev 03 - 7.2.1.2 */
1023 /* (proxy requires Status-Line, so never true for proxy)*/
1024 if (0 == r->http_status && light_btst(r->resp_htags, HTTP_HEADER_LOCATION)){
1025 r->http_status = 302;
1026 }
1027
1028 return 0;
1029 }
1030
1031
1032 static http_response_send_1xx_cb http_response_send_1xx_h1;
1033 static http_response_send_1xx_cb http_response_send_1xx_h2;
1034
1035 void
http_response_send_1xx_cb_set(http_response_send_1xx_cb fn,int vers)1036 http_response_send_1xx_cb_set (http_response_send_1xx_cb fn, int vers)
1037 {
1038 if (vers >= HTTP_VERSION_2)
1039 http_response_send_1xx_h2 = fn;
1040 else if (vers == HTTP_VERSION_1_1)
1041 http_response_send_1xx_h1 = fn;
1042 }
1043
1044
1045 int
http_response_send_1xx(request_st * const r)1046 http_response_send_1xx (request_st * const r)
1047 {
1048 http_response_send_1xx_cb http_response_send_1xx_fn = NULL;
1049 if (r->http_version >= HTTP_VERSION_2)
1050 http_response_send_1xx_fn = http_response_send_1xx_h2;
1051 else if (r->http_version == HTTP_VERSION_1_1)
1052 http_response_send_1xx_fn = http_response_send_1xx_h1;
1053
1054 if (http_response_send_1xx_fn && !http_response_send_1xx_fn(r, r->con))
1055 return 0; /* error occurred */
1056
1057 http_response_header_clear(r);
1058 return 1; /* 1xx response handled */
1059 }
1060
1061
1062 __attribute_cold__
1063 __attribute_noinline__
1064 static int
http_response_check_1xx(request_st * const r,buffer * const restrict b,uint32_t hlen,uint32_t dlen)1065 http_response_check_1xx (request_st * const r, buffer * const restrict b, uint32_t hlen, uint32_t dlen)
1066 {
1067 /* pass through unset r->http_status (not 1xx) or 101 Switching Protocols */
1068 if (0 == r->http_status || 101 == r->http_status)
1069 return 0; /* pass through as-is; do not loop for addtl response hdrs */
1070
1071 /* discard 1xx response from b; already processed
1072 * (but further response might follow in b, so preserve addtl data) */
1073 if (dlen)
1074 memmove(b->ptr, b->ptr+hlen, dlen);
1075 buffer_truncate(b, dlen);
1076
1077 /* Note: while GW_AUTHORIZER mode is not expected to return 1xx, as a
1078 * feature, 1xx responses from authorizer are passed back to client */
1079
1080 return http_response_send_1xx(r);
1081 /* 0: error, 1: 1xx response handled; loop for next response headers */
1082 }
1083
1084
1085 __attribute_noinline__
http_response_parse_headers(request_st * const r,http_response_opts * const opts,buffer * const b)1086 handler_t http_response_parse_headers(request_st * const r, http_response_opts * const opts, buffer * const b) {
1087 /**
1088 * possible formats of response headers:
1089 *
1090 * proxy or NPH (non-parsed headers):
1091 *
1092 * HTTP/1.0 200 Ok\n
1093 * Header: Value\n
1094 * \n
1095 *
1096 * CGI:
1097 *
1098 * Header: Value\n
1099 * Status: 200\n
1100 * \n
1101 *
1102 * and different mixes of \n and \r\n combinations
1103 *
1104 * Some users also forget about CGI and just send a response
1105 * and hope we handle it. No headers, no header-content separator
1106 */
1107 const char *bstart;
1108 uint32_t blen;
1109
1110 do {
1111 uint32_t header_len, is_nph = 0;
1112 unsigned short hoff[8192]; /* max num header lines + 3; 16k on stack */
1113 hoff[0] = 1; /* number of lines */
1114 hoff[1] = 0; /* base offset for all lines */
1115 hoff[2] = 0; /* offset from base for 2nd line; init 0 to detect '\n' */
1116 blen = buffer_clen(b);
1117 header_len = http_header_parse_hoff(b->ptr, blen, hoff);
1118 if ((header_len ? header_len : blen) > MAX_HTTP_RESPONSE_FIELD_SIZE) {
1119 log_error(r->conf.errh, __FILE__, __LINE__,
1120 "response headers too large for %s", r->uri.path.ptr);
1121 r->http_status = 502; /* Bad Gateway */
1122 r->handler_module = NULL;
1123 return HANDLER_FINISHED;
1124 }
1125 if (hoff[2]) { /*(at least one newline found if offset is non-zero)*/
1126 /*("HTTP/1.1 200 " is at least 13 chars + \r\n; 12 w/o final ' ')*/
1127 is_nph = hoff[2] >= 12 && 0 == memcmp(b->ptr, "HTTP/", 5);
1128 if (!is_nph) {
1129 const char * colon = memchr(b->ptr, ':', hoff[2]-1);
1130 if (__builtin_expect( (NULL == colon), 0)) {
1131 if (hoff[2] <= 2 && (1 == hoff[2] || b->ptr[0] == '\r')) {
1132 /* no HTTP headers */
1133 }
1134 else if (opts->backend == BACKEND_CGI) {
1135 /* no HTTP headers, but body (special-case for CGI)*/
1136 /* no colon found; does not appear to be HTTP headers */
1137 if (0 != http_chunk_append_buffer(r, b)) {
1138 return HANDLER_ERROR;
1139 }
1140 r->http_status = 200; /* OK */
1141 r->resp_body_started = 1;
1142 return HANDLER_GO_ON;
1143 }
1144 else {
1145 /* invalid response headers */
1146 r->http_status = 502; /* Bad Gateway */
1147 r->handler_module = NULL;
1148 return HANDLER_FINISHED;
1149 }
1150 }
1151 }
1152 } /* else no newline yet; partial header line?) */
1153 if (0 == header_len) /* headers incomplete */
1154 return HANDLER_GO_ON;
1155
1156 /* the body starts after the EOL */
1157 bstart = b->ptr + header_len;
1158 blen -= header_len;
1159
1160 if (0 != http_response_process_headers(r, opts, b->ptr, hoff, is_nph))
1161 return HANDLER_ERROR;
1162
1163 } while (r->http_status < 200
1164 && http_response_check_1xx(r, b, bstart - b->ptr, blen));
1165
1166 r->resp_body_started = 1;
1167
1168 if (opts->authorizer
1169 && (r->http_status == 0 || r->http_status == 200)) {
1170 return HANDLER_GO_ON;
1171 }
1172
1173 if (NULL == r->handler_module) {
1174 return HANDLER_FINISHED;
1175 }
1176
1177 if (opts->local_redir && r->http_status >= 300 && r->http_status < 400
1178 && 0 == blen) {
1179 /* (Might not have begun to receive body yet, but do skip local-redir
1180 * if we already have started receiving a response body (blen > 0)) */
1181 /*(light_btst(r->resp_htags, HTTP_HEADER_LOCATION))*/
1182 handler_t rc = http_cgi_local_redir(r);
1183 if (rc != HANDLER_GO_ON) return rc;
1184 }
1185
1186 if (opts->xsendfile_allow) {
1187 buffer *vb;
1188 /* X-Sendfile2 is deprecated; historical for fastcgi */
1189 if (opts->backend == BACKEND_FASTCGI
1190 && NULL != (vb = http_header_response_get(r, HTTP_HEADER_OTHER,
1191 CONST_STR_LEN("X-Sendfile2")))) {
1192 http_response_xsendfile2(r, vb, opts->xsendfile_docroot);
1193 /* http_header_response_unset() shortcut for HTTP_HEADER_OTHER */
1194 buffer_clear(vb); /*(do not send to client)*/
1195 if (NULL == r->handler_module)
1196 r->resp_body_started = 0;
1197 return HANDLER_FINISHED;
1198 } else if (NULL != (vb = http_header_response_get(r, HTTP_HEADER_OTHER,
1199 CONST_STR_LEN("X-Sendfile")))
1200 || (opts->backend == BACKEND_FASTCGI /* X-LIGHTTPD-send-file is deprecated; historical for fastcgi */
1201 && NULL != (vb = http_header_response_get(r, HTTP_HEADER_OTHER,
1202 CONST_STR_LEN("X-LIGHTTPD-send-file"))))) {
1203 http_response_xsendfile(r, vb, opts->xsendfile_docroot);
1204 /* http_header_response_unset() shortcut for HTTP_HEADER_OTHER */
1205 buffer_clear(vb); /*(do not send to client)*/
1206 if (NULL == r->handler_module)
1207 r->resp_body_started = 0;
1208 return HANDLER_FINISHED;
1209 }
1210 }
1211
1212 if (blen > 0) {
1213 /* modules which set opts->parse() (e.g. mod_ajp13, mod_fastcgi) must
1214 * not pass buffer with excess data to this routine (and do not do so
1215 * due to framing of response headers separately from response body) */
1216 int rc = http_response_append_mem(r, bstart, blen);
1217 if (__builtin_expect( (0 != rc), 0))
1218 return HANDLER_ERROR;
1219 }
1220
1221 /* (callback for response headers complete) */
1222 return (opts->headers) ? opts->headers(r, opts) : HANDLER_GO_ON;
1223 }
1224
1225
http_response_read(request_st * const r,http_response_opts * const opts,buffer * const b,fdnode * const fdn)1226 handler_t http_response_read(request_st * const r, http_response_opts * const opts, buffer * const b, fdnode * const fdn) {
1227 const int fd = fdn->fd;
1228 ssize_t n;
1229 size_t avail;
1230 /*size_t total = 0;*/
1231 do {
1232 unsigned int toread = 0;
1233 avail = buffer_string_space(b);
1234
1235 if (0 == fdevent_ioctl_fionread(fd, opts->fdfmt, (int *)&toread)) {
1236
1237 #ifdef HAVE_SPLICE
1238 /* check if worthwhile to splice() to avoid copying to userspace */
1239 if (opts->simple_accum) {
1240 int rc = http_response_append_splice(r, opts, b, fd, toread);
1241 if (rc) {
1242 if (__builtin_expect( (rc > 0), 1))
1243 break;
1244 return HANDLER_ERROR;
1245 } /*(fall through to handle traditionally)*/
1246 }
1247 #endif
1248
1249 if (avail < toread) {
1250 uint32_t blen = buffer_clen(b);
1251 if (toread + blen < 4096)
1252 toread = 4095 - blen;
1253 else if (toread > opts->max_per_read)
1254 toread = opts->max_per_read;
1255 /* reduce amount read for response headers to reduce extra data
1256 * copying for initial data following response headers
1257 * (see http_response_parse_headers())
1258 * (This seems reasonable to do even if opts->parse is set)
1259 * (default chunk buffer is 8k; typical response headers < 8k)
1260 * (An alternative might be the opposite: read extra, e.g. 128k,
1261 * if data available, in order to write to temp files sooner)*/
1262 if (toread > 8192 && !r->resp_body_started) toread = 8192;
1263 }
1264 else if (0 == toread) {
1265 #if 0
1266 return (fdevent_fdnode_interest(fdn) & FDEVENT_IN)
1267 ? HANDLER_FINISHED /* read finished */
1268 : HANDLER_GO_ON; /* optimistic read; data not ready */
1269 #else
1270 if (!(fdevent_fdnode_interest(fdn) & FDEVENT_IN)) {
1271 if (!(r->conf.stream_response_body
1272 & FDEVENT_STREAM_RESPONSE_POLLRDHUP))
1273 return HANDLER_GO_ON;/*optimistic read; data not ready*/
1274 }
1275 if (0 == avail) /* let read() below indicate if EOF or EAGAIN */
1276 toread = 1024;
1277 #endif
1278 }
1279 }
1280 else if (avail < 1024) {
1281 toread = 4095 - avail;
1282 }
1283
1284 if (r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN) {
1285 off_t cqlen = chunkqueue_length(&r->write_queue);
1286 if (cqlen + (off_t)toread > 65536 - 4096) {
1287 if (!r->con->is_writable) {
1288 /*(defer removal of FDEVENT_IN interest since
1289 * connection_state_machine() might be able to send data
1290 * immediately, unless !con->is_writable, where
1291 * connection_state_machine() might not loop back to call
1292 * mod_proxy_handle_subrequest())*/
1293 fdevent_fdnode_event_clr(r->con->srv->ev, fdn, FDEVENT_IN);
1294 }
1295 if (cqlen >= 65536-1) {
1296 if (buffer_is_blank(b))
1297 chunk_buffer_yield(b); /*(improve large buf reuse)*/
1298 return HANDLER_GO_ON;
1299 }
1300 toread = 65536 - 1 - (unsigned int)cqlen;
1301 /* Note: heuristic is fuzzy in that it limits how much to read
1302 * from backend based on how much is pending to write to client.
1303 * Modules where data from backend is framed (e.g. FastCGI) may
1304 * want to limit how much is buffered from backend while waiting
1305 * for a complete data frame or data packet from backend. */
1306 }
1307 }
1308
1309 if (avail < toread) {
1310 /*(add avail+toread to reduce allocations when ioctl EOPNOTSUPP)*/
1311 avail = toread < opts->max_per_read && avail
1312 ? avail-1+toread
1313 : toread;
1314 avail = chunk_buffer_prepare_append(b, avail);
1315 }
1316
1317 n = read(fd, b->ptr+buffer_clen(b), avail);
1318
1319 if (n < 0) {
1320 switch (errno) {
1321 case EAGAIN:
1322 #ifdef EWOULDBLOCK
1323 #if EWOULDBLOCK != EAGAIN
1324 case EWOULDBLOCK:
1325 #endif
1326 #endif
1327 case EINTR:
1328 if (buffer_is_blank(b))
1329 chunk_buffer_yield(b); /*(improve large buf reuse)*/
1330 return HANDLER_GO_ON;
1331 default:
1332 log_perror(r->conf.errh, __FILE__, __LINE__,
1333 "read() %d %d", r->con->fd, fd);
1334 return HANDLER_ERROR;
1335 }
1336 }
1337
1338 buffer_commit(b, (size_t)n);
1339 #ifdef __COVERITY__
1340 /* Coverity Scan overlooks the effect of buffer_commit() */
1341 b->ptr[buffer_clen(b)+n] = '\0';
1342 #endif
1343
1344 if (NULL != opts->parse) {
1345 handler_t rc = opts->parse(r, opts, b, (size_t)n);
1346 if (rc != HANDLER_GO_ON) return rc;
1347 } else if (0 == n) {
1348 if (buffer_is_blank(b))
1349 chunk_buffer_yield(b); /*(improve large buf reuse)*/
1350 else if (opts->simple_accum) {
1351 /*(flush small reads previously accumulated in b)*/
1352 int rc = http_response_append_buffer(r, b, 0); /*(0 to flush)*/
1353 chunk_buffer_yield(b); /*(improve large buf reuse)*/
1354 if (__builtin_expect( (0 != rc), 0)) {
1355 /* error writing to tempfile;
1356 * truncate response or send 500 if nothing sent yet */
1357 return HANDLER_ERROR;
1358 }
1359 }
1360 /* note: no further data is sent to backend after read EOF on socket
1361 * (not checking for half-closed TCP socket)
1362 * (backend should read all data desired prior to closing socket,
1363 * though might send app-level close data frame, if applicable) */
1364 return HANDLER_FINISHED; /* read finished */
1365 } else if (0 == r->resp_body_started) {
1366 /* split header from body */
1367 handler_t rc = http_response_parse_headers(r, opts, b);
1368 if (rc != HANDLER_GO_ON) return rc;
1369 /* accumulate response in b until headers completed (or error)*/
1370 if (r->resp_body_started) {
1371 buffer_clear(b);
1372 /* check if Content-Length provided and response body received
1373 * (done here instead of http_response_process_headers() since
1374 * backends which set opts->parse() might handle differently)*/
1375 if (0 == r->resp_body_scratchpad)
1376 r->resp_body_finished = 1;
1377 /* enable simple accumulation of small reads in some situations
1378 * no Content-Length (will read to EOF)
1379 * Content-Length (will read until r->resp_body_scratchpad == 0)
1380 * not chunked-encoding
1381 * not bufmin streaming
1382 * (no custom parse routine set for opts->parse()) */
1383 else if (!r->resp_decode_chunked /* && NULL == opts->parse */
1384 && !(r->conf.stream_response_body
1385 & FDEVENT_STREAM_RESPONSE_BUFMIN))
1386 opts->simple_accum = 1;
1387 }
1388 } else {
1389 /* flush b (do not accumulate small reads) if streaming and might
1390 * write to client since there is a chance that r->write_queue is
1391 * fully written to client (no more temp files) and then we do not
1392 * want to hold onto buffered data in b for an indeterminate time
1393 * until next read of data from backend */
1394 int simple_accum = opts->simple_accum
1395 && (!(r->conf.stream_response_body
1396 & FDEVENT_STREAM_RESPONSE)
1397 || !r->con->is_writable);
1398 int rc = http_response_append_buffer(r, b, simple_accum);
1399 if (__builtin_expect( (0 != rc), 0)) {
1400 /* error writing to tempfile;
1401 * truncate response or send 500 if nothing sent yet */
1402 return HANDLER_ERROR;
1403 }
1404 /*buffer_clear(b);*//*http_response_append_buffer() clears*/
1405 /* small reads might accumulate in b; not necessarily cleared */
1406 }
1407
1408 if (r->conf.stream_response_body & FDEVENT_STREAM_RESPONSE_BUFMIN) {
1409 if (chunkqueue_length(&r->write_queue) > 65536 - 4096) {
1410 /*(defer removal of FDEVENT_IN interest since
1411 * connection_state_machine() might be able to send
1412 * data immediately, unless !con->is_writable, where
1413 * connection_state_machine() might not loop back to
1414 * call the subrequest handler)*/
1415 if (!r->con->is_writable)
1416 fdevent_fdnode_event_clr(r->con->srv->ev, fdn, FDEVENT_IN);
1417 break;
1418 }
1419 }
1420 } while (!r->resp_body_started); /*(loop to read large response headers)*/
1421 /*while (0);*//*(extra logic might benefit systems without FIONREAD)*/
1422 /*while ((size_t)n == avail && (total += (size_t)n) < opts->max_per_read);*/
1423 /* else emptied kernel read buffer or partial read or reached read limit */
1424
1425 if (buffer_is_blank(b)) chunk_buffer_yield(b); /*(improve large buf reuse)*/
1426
1427 return (!r->resp_body_finished ? HANDLER_GO_ON : HANDLER_FINISHED);
1428 }
1429