1 /* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements. See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License. You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 /* HTTP routines for Apache proxy */
19 #include "mod_proxy.h"
22 module AP_MODULE_DECLARE_DATA proxy_http_module;
24 static apr_status_t ap_proxy_http_cleanup(const char *scheme,
26 proxy_conn_rec *backend);
29 * Canonicalise http-like URLs.
30 * scheme is the scheme for the URL
31 * url is the URL starting with the first '/'
32 * def_port is the default port for this scheme.
34 static int proxy_http_canon(request_rec *r, char *url)
36 char *host, *path, sport[7];
40 apr_port_t port, def_port;
42 /* ap_port_of_scheme() */
43 if (strncasecmp(url, "http:", 5) == 0) {
47 else if (strncasecmp(url, "https:", 6) == 0) {
54 def_port = apr_uri_port_of_scheme(scheme);
56 ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, r->server,
57 "proxy: HTTP: canonicalising URL %s", url);
60 * We break the URL into host, port, path, search
63 err = ap_proxy_canon_netloc(r->pool, &url, NULL, NULL, &host, &port);
65 ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
66 "error parsing URL %s: %s",
68 return HTTP_BAD_REQUEST;
72 * now parse path/search args, according to rfc1738:
75 * In a reverse proxy, our URL has been processed, so canonicalise
76 * unless proxy-nocanon is set to say it's raw
77 * In a forward proxy, we have and MUST NOT MANGLE the original.
79 switch (r->proxyreq) {
80 default: /* wtf are we doing here? */
81 case PROXYREQ_REVERSE:
82 if (apr_table_get(r->notes, "proxy-nocanon")) {
83 path = url; /* this is the raw path */
86 path = ap_proxy_canonenc(r->pool, url, strlen(url),
87 enc_path, 0, r->proxyreq);
97 return HTTP_BAD_REQUEST;
100 apr_snprintf(sport, sizeof(sport), ":%d", port);
104 if (ap_strchr_c(host, ':')) { /* if literal IPv6 address */
105 host = apr_pstrcat(r->pool, "[", host, "]", NULL);
107 r->filename = apr_pstrcat(r->pool, "proxy:", scheme, "://", host, sport,
108 "/", path, (search) ? "?" : "", (search) ? search : "", NULL);
112 /* Clear all connection-based headers from the incoming headers table */
113 typedef struct header_dptr {
118 static ap_regex_t *warn_rx;
119 static int clean_warning_headers(void *data, const char *key, const char *val)
121 apr_table_t *headers = ((header_dptr*)data)->table;
122 apr_pool_t *pool = ((header_dptr*)data)->pool;
125 apr_time_t warn_time;
126 const int nmatch = 3;
127 ap_regmatch_t pmatch[3];
129 if (headers == NULL) {
130 ((header_dptr*)data)->table = headers = apr_table_make(pool, 2);
133 * Parse this, suckers!
135 * Warning = "Warning" ":" 1#warning-value
137 * warning-value = warn-code SP warn-agent SP warn-text
141 * warn-agent = ( host [ ":" port ] ) | pseudonym
142 * ; the name or pseudonym of the server adding
143 * ; the Warning header, for use in debugging
144 * warn-text = quoted-string
145 * warn-date = <"> HTTP-date <">
147 * Buggrit, use a bloomin' regexp!
148 * (\d{3}\s+\S+\s+\".*?\"(\s+\"(.*?)\")?) --> whole in $1, date in $3
150 while (!ap_regexec(warn_rx, val, nmatch, pmatch, 0)) {
151 warning = apr_pstrndup(pool, val+pmatch[0].rm_so,
152 pmatch[0].rm_eo - pmatch[0].rm_so);
154 if (pmatch[2].rm_eo > pmatch[2].rm_so) {
155 /* OK, we have a date here */
156 date = apr_pstrndup(pool, val+pmatch[2].rm_so,
157 pmatch[2].rm_eo - pmatch[2].rm_so);
158 warn_time = apr_date_parse_http(date);
160 if (!warn_time || (warn_time == ((header_dptr*)data)->time)) {
161 apr_table_addn(headers, key, warning);
163 val += pmatch[0].rm_eo;
167 static apr_table_t *ap_proxy_clean_warnings(apr_pool_t *p, apr_table_t *headers)
172 x.time = apr_date_parse_http(apr_table_get(headers, "Date"));
173 apr_table_do(clean_warning_headers, &x, headers, "Warning", NULL);
174 if (x.table != NULL) {
175 apr_table_unset(headers, "Warning");
176 return apr_table_overlay(p, headers, x.table);
182 static int clear_conn_headers(void *data, const char *key, const char *val)
184 apr_table_t *headers = ((header_dptr*)data)->table;
185 apr_pool_t *pool = ((header_dptr*)data)->pool;
187 char *next = apr_pstrdup(pool, val);
190 while (*next && !apr_isspace(*next) && (*next != ',')) {
193 while (*next && (apr_isspace(*next) || (*next == ','))) {
196 apr_table_unset(headers, name);
200 static void ap_proxy_clear_connection(apr_pool_t *p, apr_table_t *headers)
205 apr_table_unset(headers, "Proxy-Connection");
206 apr_table_do(clear_conn_headers, &x, headers, "Connection", NULL);
207 apr_table_unset(headers, "Connection");
209 static void add_te_chunked(apr_pool_t *p,
210 apr_bucket_alloc_t *bucket_alloc,
211 apr_bucket_brigade *header_brigade)
215 const char te_hdr[] = "Transfer-Encoding: chunked" CRLF;
217 buf = apr_pmemdup(p, te_hdr, sizeof(te_hdr)-1);
218 ap_xlate_proto_to_ascii(buf, sizeof(te_hdr)-1);
220 e = apr_bucket_pool_create(buf, sizeof(te_hdr)-1, p, bucket_alloc);
221 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
224 static void add_cl(apr_pool_t *p,
225 apr_bucket_alloc_t *bucket_alloc,
226 apr_bucket_brigade *header_brigade,
232 buf = apr_pstrcat(p, "Content-Length: ",
236 ap_xlate_proto_to_ascii(buf, strlen(buf));
237 e = apr_bucket_pool_create(buf, strlen(buf), p, bucket_alloc);
238 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
241 #define ASCII_CRLF "\015\012"
242 #define ASCII_ZERO "\060"
244 static void terminate_headers(apr_bucket_alloc_t *bucket_alloc,
245 apr_bucket_brigade *header_brigade)
249 /* add empty line at the end of the headers */
250 e = apr_bucket_immortal_create(ASCII_CRLF, 2, bucket_alloc);
251 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
254 static int pass_brigade(apr_bucket_alloc_t *bucket_alloc,
255 request_rec *r, proxy_conn_rec *p_conn,
256 conn_rec *origin, apr_bucket_brigade *bb,
260 apr_off_t transferred;
263 apr_bucket *e = apr_bucket_flush_create(bucket_alloc);
264 APR_BRIGADE_INSERT_TAIL(bb, e);
266 apr_brigade_length(bb, 0, &transferred);
267 if (transferred != -1)
268 p_conn->worker->s->transferred += transferred;
269 status = ap_pass_brigade(origin->output_filters, bb);
270 if (status != APR_SUCCESS) {
271 ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
272 "proxy: pass request body failed to %pI (%s)",
273 p_conn->addr, p_conn->hostname);
274 if (origin->aborted) {
275 if (strcmp(apr_table_get(origin->notes,
276 "SSL_connect_rv"), "err") == 0) {
277 return ap_proxyerror(r, HTTP_INTERNAL_SERVER_ERROR,
278 "Error during SSL Handshake with"
281 return APR_STATUS_IS_TIMEUP(status) ? HTTP_GATEWAY_TIME_OUT : HTTP_BAD_GATEWAY;
284 return HTTP_BAD_REQUEST;
287 apr_brigade_cleanup(bb);
291 #define MAX_MEM_SPOOL 16384
293 static int stream_reqbody_chunked(apr_pool_t *p,
295 proxy_conn_rec *p_conn,
297 apr_bucket_brigade *header_brigade,
298 apr_bucket_brigade *input_brigade)
300 int seen_eos = 0, rv = OK;
304 apr_bucket_alloc_t *bucket_alloc = r->connection->bucket_alloc;
305 apr_bucket_brigade *bb;
308 add_te_chunked(p, bucket_alloc, header_brigade);
309 terminate_headers(bucket_alloc, header_brigade);
311 while (!APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade)))
313 char chunk_hdr[20]; /* must be here due to transient bucket. */
315 /* If this brigade contains EOS, either stop or remove it. */
316 if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {
319 /* We can't pass this EOS to the output_filters. */
320 e = APR_BRIGADE_LAST(input_brigade);
321 apr_bucket_delete(e);
324 apr_brigade_length(input_brigade, 1, &bytes);
326 hdr_len = apr_snprintf(chunk_hdr, sizeof(chunk_hdr),
327 "%" APR_UINT64_T_HEX_FMT CRLF,
328 (apr_uint64_t)bytes);
330 ap_xlate_proto_to_ascii(chunk_hdr, hdr_len);
331 e = apr_bucket_transient_create(chunk_hdr, hdr_len,
333 APR_BRIGADE_INSERT_HEAD(input_brigade, e);
336 * Append the end-of-chunk CRLF
338 e = apr_bucket_immortal_create(ASCII_CRLF, 2, bucket_alloc);
339 APR_BRIGADE_INSERT_TAIL(input_brigade, e);
341 if (header_brigade) {
342 /* we never sent the header brigade, so go ahead and
343 * take care of that now
348 * Save input_brigade in bb brigade. (At least) in the SSL case
349 * input_brigade contains transient buckets whose data would get
350 * overwritten during the next call of ap_get_brigade in the loop.
351 * ap_save_brigade ensures these buckets to be set aside.
352 * Calling ap_save_brigade with NULL as filter is OK, because
353 * bb brigade already has been created and does not need to get
354 * created by ap_save_brigade.
356 status = ap_save_brigade(NULL, &bb, &input_brigade, p);
357 if (status != APR_SUCCESS) {
358 return HTTP_INTERNAL_SERVER_ERROR;
361 header_brigade = NULL;
367 /* The request is flushed below this loop with chunk EOS header */
368 rv = pass_brigade(bucket_alloc, r, p_conn, origin, bb, 0);
377 status = ap_get_brigade(r->input_filters, input_brigade,
378 AP_MODE_READBYTES, APR_BLOCK_READ,
381 if (status != APR_SUCCESS) {
382 return HTTP_BAD_REQUEST;
386 if (header_brigade) {
387 /* we never sent the header brigade because there was no request body;
393 if (!APR_BRIGADE_EMPTY(input_brigade)) {
394 /* input brigade still has an EOS which we can't pass to the output_filters. */
395 e = APR_BRIGADE_LAST(input_brigade);
396 AP_DEBUG_ASSERT(APR_BUCKET_IS_EOS(e));
397 apr_bucket_delete(e);
402 e = apr_bucket_immortal_create(ASCII_ZERO ASCII_CRLF
406 APR_BRIGADE_INSERT_TAIL(bb, e);
408 if (apr_table_get(r->subprocess_env, "proxy-sendextracrlf")) {
409 e = apr_bucket_immortal_create(ASCII_CRLF, 2, bucket_alloc);
410 APR_BRIGADE_INSERT_TAIL(bb, e);
413 /* Now we have headers-only, or the chunk EOS mark; flush it */
414 rv = pass_brigade(bucket_alloc, r, p_conn, origin, bb, 1);
418 static int stream_reqbody_cl(apr_pool_t *p,
420 proxy_conn_rec *p_conn,
422 apr_bucket_brigade *header_brigade,
423 apr_bucket_brigade *input_brigade,
424 const char *old_cl_val)
426 int seen_eos = 0, rv = 0;
427 apr_status_t status = APR_SUCCESS;
428 apr_bucket_alloc_t *bucket_alloc = r->connection->bucket_alloc;
429 apr_bucket_brigade *bb;
431 apr_off_t cl_val = 0;
433 apr_off_t bytes_streamed = 0;
438 add_cl(p, bucket_alloc, header_brigade, old_cl_val);
439 status = apr_strtoff(&cl_val, old_cl_val, &endstr, 10);
441 if (status || *endstr || endstr == old_cl_val || cl_val < 0) {
442 ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
443 "proxy: could not parse request Content-Length (%s)",
445 return HTTP_BAD_REQUEST;
448 terminate_headers(bucket_alloc, header_brigade);
450 while (!APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade)))
452 apr_brigade_length(input_brigade, 1, &bytes);
453 bytes_streamed += bytes;
455 /* If this brigade contains EOS, either stop or remove it. */
456 if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {
459 /* We can't pass this EOS to the output_filters. */
460 e = APR_BRIGADE_LAST(input_brigade);
461 apr_bucket_delete(e);
463 if (apr_table_get(r->subprocess_env, "proxy-sendextracrlf")) {
464 e = apr_bucket_immortal_create(ASCII_CRLF, 2, bucket_alloc);
465 APR_BRIGADE_INSERT_TAIL(input_brigade, e);
469 /* C-L < bytes streamed?!?
470 * We will error out after the body is completely
471 * consumed, but we can't stream more bytes at the
472 * back end since they would in part be interpreted
473 * as another request! If nothing is sent, then
476 * Prevents HTTP Response Splitting.
478 if (bytes_streamed > cl_val) {
479 ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
480 "proxy: read more bytes of request body than expected "
481 "(got %" APR_OFF_T_FMT ", expected %" APR_OFF_T_FMT ")",
482 bytes_streamed, cl_val);
483 return HTTP_INTERNAL_SERVER_ERROR;
486 if (header_brigade) {
487 /* we never sent the header brigade, so go ahead and
488 * take care of that now
493 * Save input_brigade in bb brigade. (At least) in the SSL case
494 * input_brigade contains transient buckets whose data would get
495 * overwritten during the next call of ap_get_brigade in the loop.
496 * ap_save_brigade ensures these buckets to be set aside.
497 * Calling ap_save_brigade with NULL as filter is OK, because
498 * bb brigade already has been created and does not need to get
499 * created by ap_save_brigade.
501 status = ap_save_brigade(NULL, &bb, &input_brigade, p);
502 if (status != APR_SUCCESS) {
503 return HTTP_INTERNAL_SERVER_ERROR;
506 header_brigade = NULL;
512 /* Once we hit EOS, we are ready to flush. */
513 rv = pass_brigade(bucket_alloc, r, p_conn, origin, bb, seen_eos);
522 status = ap_get_brigade(r->input_filters, input_brigade,
523 AP_MODE_READBYTES, APR_BLOCK_READ,
526 if (status != APR_SUCCESS) {
527 return HTTP_BAD_REQUEST;
531 if (bytes_streamed != cl_val) {
532 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
533 "proxy: client %s given Content-Length did not match"
534 " number of body bytes read", r->connection->remote_ip);
535 return HTTP_BAD_REQUEST;
538 if (header_brigade) {
539 /* we never sent the header brigade since there was no request
540 * body; send it now with the flush flag
543 return(pass_brigade(bucket_alloc, r, p_conn, origin, bb, 1));
549 static int spool_reqbody_cl(apr_pool_t *p,
551 proxy_conn_rec *p_conn,
553 apr_bucket_brigade *header_brigade,
554 apr_bucket_brigade *input_brigade,
559 apr_bucket_alloc_t *bucket_alloc = r->connection->bucket_alloc;
560 apr_bucket_brigade *body_brigade;
562 apr_off_t bytes, bytes_spooled = 0, fsize = 0;
563 apr_file_t *tmpfile = NULL;
566 body_brigade = apr_brigade_create(p, bucket_alloc);
568 limit = ap_get_limit_req_body(r);
570 while (!APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(input_brigade)))
572 /* If this brigade contains EOS, either stop or remove it. */
573 if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {
576 /* We can't pass this EOS to the output_filters. */
577 e = APR_BRIGADE_LAST(input_brigade);
578 apr_bucket_delete(e);
581 apr_brigade_length(input_brigade, 1, &bytes);
583 if (bytes_spooled + bytes > MAX_MEM_SPOOL) {
585 * LimitRequestBody does not affect Proxy requests (Should it?).
586 * Let it take effect if we decide to store the body in a
587 * temporary file on disk.
589 if (bytes_spooled + bytes > limit) {
590 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
591 "proxy: Request body is larger than the"
592 " configured limit of %" APR_OFF_T_FMT ".",
594 return HTTP_REQUEST_ENTITY_TOO_LARGE;
596 /* can't spool any more in memory; write latest brigade to disk */
597 if (tmpfile == NULL) {
598 const char *temp_dir;
601 status = apr_temp_dir_get(&temp_dir, p);
602 if (status != APR_SUCCESS) {
603 ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
604 "proxy: search for temporary directory failed");
605 return HTTP_INTERNAL_SERVER_ERROR;
607 apr_filepath_merge(&template, temp_dir,
608 "modproxy.tmp.XXXXXX",
609 APR_FILEPATH_NATIVE, p);
610 status = apr_file_mktemp(&tmpfile, template, 0, p);
611 if (status != APR_SUCCESS) {
612 ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
613 "proxy: creation of temporary file in directory %s failed",
615 return HTTP_INTERNAL_SERVER_ERROR;
618 for (e = APR_BRIGADE_FIRST(input_brigade);
619 e != APR_BRIGADE_SENTINEL(input_brigade);
620 e = APR_BUCKET_NEXT(e)) {
622 apr_size_t bytes_read, bytes_written;
624 apr_bucket_read(e, &data, &bytes_read, APR_BLOCK_READ);
625 status = apr_file_write_full(tmpfile, data, bytes_read, &bytes_written);
626 if (status != APR_SUCCESS) {
627 const char *tmpfile_name;
629 if (apr_file_name_get(&tmpfile_name, tmpfile) != APR_SUCCESS) {
630 tmpfile_name = "(unknown)";
632 ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
633 "proxy: write to temporary file %s failed",
635 return HTTP_INTERNAL_SERVER_ERROR;
637 AP_DEBUG_ASSERT(bytes_read == bytes_written);
638 fsize += bytes_written;
640 apr_brigade_cleanup(input_brigade);
645 * Save input_brigade in body_brigade. (At least) in the SSL case
646 * input_brigade contains transient buckets whose data would get
647 * overwritten during the next call of ap_get_brigade in the loop.
648 * ap_save_brigade ensures these buckets to be set aside.
649 * Calling ap_save_brigade with NULL as filter is OK, because
650 * body_brigade already has been created and does not need to get
651 * created by ap_save_brigade.
653 status = ap_save_brigade(NULL, &body_brigade, &input_brigade, p);
654 if (status != APR_SUCCESS) {
655 return HTTP_INTERNAL_SERVER_ERROR;
660 bytes_spooled += bytes;
666 status = ap_get_brigade(r->input_filters, input_brigade,
667 AP_MODE_READBYTES, APR_BLOCK_READ,
670 if (status != APR_SUCCESS) {
671 return HTTP_BAD_REQUEST;
675 if (bytes_spooled || force_cl) {
676 add_cl(p, bucket_alloc, header_brigade, apr_off_t_toa(p, bytes_spooled));
678 terminate_headers(bucket_alloc, header_brigade);
679 APR_BRIGADE_CONCAT(header_brigade, body_brigade);
681 apr_brigade_insert_file(header_brigade, tmpfile, 0, fsize, p);
683 if (apr_table_get(r->subprocess_env, "proxy-sendextracrlf")) {
684 e = apr_bucket_immortal_create(ASCII_CRLF, 2, bucket_alloc);
685 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
687 /* This is all a single brigade, pass with flush flagged */
688 return(pass_brigade(bucket_alloc, r, p_conn, origin, header_brigade, 1));
692 int ap_proxy_http_request(apr_pool_t *p, request_rec *r,
693 proxy_conn_rec *p_conn, proxy_worker *worker,
694 proxy_server_conf *conf,
696 char *url, char *server_portstr)
698 conn_rec *c = r->connection;
699 apr_bucket_alloc_t *bucket_alloc = c->bucket_alloc;
700 apr_bucket_brigade *header_brigade;
701 apr_bucket_brigade *input_brigade;
702 apr_bucket_brigade *temp_brigade;
705 const apr_array_header_t *headers_in_array;
706 const apr_table_entry_t *headers_in;
709 enum rb_methods {RB_INIT, RB_STREAM_CL, RB_STREAM_CHUNKED, RB_SPOOL_CL};
710 enum rb_methods rb_method = RB_INIT;
711 const char *old_cl_val = NULL;
712 const char *old_te_val = NULL;
713 apr_off_t bytes_read = 0;
716 apr_table_t *headers_in_copy;
717 proxy_dir_conf *dconf;
718 conn_rec *origin = p_conn->connection;
721 dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
722 header_brigade = apr_brigade_create(p, origin->bucket_alloc);
725 * Send the HTTP/1.1 request to the remote server
729 * To be compliant, we only use 100-Continue for requests with bodies.
730 * We also make sure we won't be talking HTTP/1.0 as well.
732 do_100_continue = (worker->ping_timeout_set
733 && ap_request_has_body(r)
734 && (PROXYREQ_REVERSE == r->proxyreq)
735 && !(apr_table_get(r->subprocess_env, "force-proxy-request-1.0")));
737 if (apr_table_get(r->subprocess_env, "force-proxy-request-1.0")) {
739 * According to RFC 2616 8.2.3 we are not allowed to forward an
740 * Expect: 100-continue to an HTTP/1.0 server. Instead we MUST return
741 * a HTTP_EXPECTATION_FAILED
743 if (r->expecting_100) {
744 return HTTP_EXPECTATION_FAILED;
746 buf = apr_pstrcat(p, r->method, " ", url, " HTTP/1.0" CRLF, NULL);
750 buf = apr_pstrcat(p, r->method, " ", url, " HTTP/1.1" CRLF, NULL);
753 if (apr_table_get(r->subprocess_env, "proxy-nokeepalive")) {
754 origin->keepalive = AP_CONN_CLOSE;
757 ap_xlate_proto_to_ascii(buf, strlen(buf));
758 e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
759 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
760 if (dconf->preserve_host == 0) {
761 if (ap_strchr_c(uri->hostname, ':')) { /* if literal IPv6 address */
762 if (uri->port_str && uri->port != DEFAULT_HTTP_PORT) {
763 buf = apr_pstrcat(p, "Host: [", uri->hostname, "]:",
764 uri->port_str, CRLF, NULL);
766 buf = apr_pstrcat(p, "Host: [", uri->hostname, "]", CRLF, NULL);
769 if (uri->port_str && uri->port != DEFAULT_HTTP_PORT) {
770 buf = apr_pstrcat(p, "Host: ", uri->hostname, ":",
771 uri->port_str, CRLF, NULL);
773 buf = apr_pstrcat(p, "Host: ", uri->hostname, CRLF, NULL);
778 /* don't want to use r->hostname, as the incoming header might have a
781 const char* hostname = apr_table_get(r->headers_in,"Host");
783 hostname = r->server->server_hostname;
784 ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,
785 "proxy: no HTTP 0.9 request (with no host line) "
786 "on incoming request and preserve host set "
787 "forcing hostname to be %s for uri %s",
791 buf = apr_pstrcat(p, "Host: ", hostname, CRLF, NULL);
793 ap_xlate_proto_to_ascii(buf, strlen(buf));
794 e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
795 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
798 if (conf->viaopt == via_block) {
799 /* Block all outgoing Via: headers */
800 apr_table_unset(r->headers_in, "Via");
801 } else if (conf->viaopt != via_off) {
802 const char *server_name = ap_get_server_name(r);
803 /* If USE_CANONICAL_NAME_OFF was configured for the proxy virtual host,
804 * then the server name returned by ap_get_server_name() is the
805 * origin server name (which does make too much sense with Via: headers)
806 * so we use the proxy vhost's name instead.
808 if (server_name == r->hostname)
809 server_name = r->server->server_hostname;
810 /* Create a "Via:" request header entry and merge it */
811 /* Generate outgoing Via: header with/without server comment: */
812 apr_table_mergen(r->headers_in, "Via",
813 (conf->viaopt == via_full)
814 ? apr_psprintf(p, "%d.%d %s%s (%s)",
815 HTTP_VERSION_MAJOR(r->proto_num),
816 HTTP_VERSION_MINOR(r->proto_num),
817 server_name, server_portstr,
818 AP_SERVER_BASEVERSION)
819 : apr_psprintf(p, "%d.%d %s%s",
820 HTTP_VERSION_MAJOR(r->proto_num),
821 HTTP_VERSION_MINOR(r->proto_num),
822 server_name, server_portstr)
826 /* Use HTTP/1.1 100-Continue as quick "HTTP ping" test
829 if (do_100_continue) {
830 apr_table_mergen(r->headers_in, "Expect", "100-Continue");
831 r->expecting_100 = 1;
834 /* X-Forwarded-*: handling
839 * These request headers are only really useful when the mod_proxy
840 * is used in a reverse proxy configuration, so that useful info
841 * about the client can be passed through the reverse proxy and on
842 * to the backend server, which may require the information to
845 * In a forward proxy situation, these options are a potential
846 * privacy violation, as information about clients behind the proxy
847 * are revealed to arbitrary servers out there on the internet.
849 * The HTTP/1.1 Via: header is designed for passing client
850 * information through proxies to a server, and should be used in
851 * a forward proxy configuation instead of X-Forwarded-*. See the
852 * ProxyVia option for details.
855 if (PROXYREQ_REVERSE == r->proxyreq) {
858 /* Add X-Forwarded-For: so that the upstream has a chance to
859 * determine, where the original request came from.
861 apr_table_mergen(r->headers_in, "X-Forwarded-For",
864 /* Add X-Forwarded-Host: so that upstream knows what the
865 * original request hostname was.
867 if ((buf = apr_table_get(r->headers_in, "Host"))) {
868 apr_table_mergen(r->headers_in, "X-Forwarded-Host", buf);
871 /* Add X-Forwarded-Server: so that upstream knows what the
872 * name of this proxy server is (if there are more than one)
873 * XXX: This duplicates Via: - do we strictly need it?
875 apr_table_mergen(r->headers_in, "X-Forwarded-Server",
876 r->server->server_hostname);
881 * Make a copy of the headers_in table before clearing the connection
882 * headers as we need the connection headers later in the http output
883 * filter to prepare the correct response headers.
885 * Note: We need to take r->pool for apr_table_copy as the key / value
886 * pairs in r->headers_in have been created out of r->pool and
887 * p might be (and actually is) a longer living pool.
888 * This would trigger the bad pool ancestry abort in apr_table_copy if
889 * apr is compiled with APR_POOL_DEBUG.
891 headers_in_copy = apr_table_copy(r->pool, r->headers_in);
892 ap_proxy_clear_connection(p, headers_in_copy);
893 /* send request headers */
894 headers_in_array = apr_table_elts(headers_in_copy);
895 headers_in = (const apr_table_entry_t *) headers_in_array->elts;
896 for (counter = 0; counter < headers_in_array->nelts; counter++) {
897 if (headers_in[counter].key == NULL
898 || headers_in[counter].val == NULL
901 || !strcasecmp(headers_in[counter].key, "Host")
903 /* Clear out hop-by-hop request headers not to send
904 * RFC2616 13.5.1 says we should strip these headers
906 || !strcasecmp(headers_in[counter].key, "Keep-Alive")
907 || !strcasecmp(headers_in[counter].key, "TE")
908 || !strcasecmp(headers_in[counter].key, "Trailer")
909 || !strcasecmp(headers_in[counter].key, "Upgrade")
914 /* Do we want to strip Proxy-Authorization ?
915 * If we haven't used it, then NO
916 * If we have used it then MAYBE: RFC2616 says we MAY propagate it.
917 * So let's make it configurable by env.
919 if (!strcasecmp(headers_in[counter].key,"Proxy-Authorization")) {
920 if (r->user != NULL) { /* we've authenticated */
921 if (!apr_table_get(r->subprocess_env, "Proxy-Chain-Auth")) {
928 /* Skip Transfer-Encoding and Content-Length for now.
930 if (!strcasecmp(headers_in[counter].key, "Transfer-Encoding")) {
931 old_te_val = headers_in[counter].val;
934 if (!strcasecmp(headers_in[counter].key, "Content-Length")) {
935 old_cl_val = headers_in[counter].val;
939 /* for sub-requests, ignore freshness/expiry headers */
941 if ( !strcasecmp(headers_in[counter].key, "If-Match")
942 || !strcasecmp(headers_in[counter].key, "If-Modified-Since")
943 || !strcasecmp(headers_in[counter].key, "If-Range")
944 || !strcasecmp(headers_in[counter].key, "If-Unmodified-Since")
945 || !strcasecmp(headers_in[counter].key, "If-None-Match")) {
950 buf = apr_pstrcat(p, headers_in[counter].key, ": ",
951 headers_in[counter].val, CRLF,
953 ap_xlate_proto_to_ascii(buf, strlen(buf));
954 e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
955 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
958 /* We have headers, let's figure out our request body... */
959 input_brigade = apr_brigade_create(p, bucket_alloc);
961 /* sub-requests never use keepalives, and mustn't pass request bodies.
962 * Because the new logic looks at input_brigade, we will self-terminate
963 * input_brigade and jump past all of the request body logic...
964 * Reading anything with ap_get_brigade is likely to consume the
965 * main request's body or read beyond EOS - which would be unplesant.
967 * An exception: when a kept_body is present, then subrequest CAN use
968 * pass request bodies, and we DONT skip the body.
970 if (!r->kept_body && r->main) {
971 /* XXX: Why DON'T sub-requests use keepalives? */
975 apr_table_unset(r->headers_in, "Content-Length");
979 apr_table_unset(r->headers_in, "Transfer-Encoding");
981 rb_method = RB_STREAM_CL;
982 e = apr_bucket_eos_create(input_brigade->bucket_alloc);
983 APR_BRIGADE_INSERT_TAIL(input_brigade, e);
987 /* WE only understand chunked. Other modules might inject
988 * (and therefore, decode) other flavors but we don't know
989 * that the can and have done so unless they they remove
990 * their decoding from the headers_in T-E list.
991 * XXX: Make this extensible, but in doing so, presume the
992 * encoding has been done by the extensions' handler, and
993 * do not modify add_te_chunked's logic
995 if (old_te_val && strcasecmp(old_te_val, "chunked") != 0) {
996 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
997 "proxy: %s Transfer-Encoding is not supported",
999 return HTTP_INTERNAL_SERVER_ERROR;
1002 if (old_cl_val && old_te_val) {
1003 ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_ENOTIMPL, r->server,
1004 "proxy: client %s (%s) requested Transfer-Encoding "
1005 "chunked body with Content-Length (C-L ignored)",
1006 c->remote_ip, c->remote_host ? c->remote_host: "");
1007 apr_table_unset(r->headers_in, "Content-Length");
1009 origin->keepalive = AP_CONN_CLOSE;
1013 /* Prefetch MAX_MEM_SPOOL bytes
1015 * This helps us avoid any election of C-L v.s. T-E
1016 * request bodies, since we are willing to keep in
1017 * memory this much data, in any case. This gives
1018 * us an instant C-L election if the body is of some
1021 temp_brigade = apr_brigade_create(p, bucket_alloc);
1023 status = ap_get_brigade(r->input_filters, temp_brigade,
1024 AP_MODE_READBYTES, APR_BLOCK_READ,
1025 MAX_MEM_SPOOL - bytes_read);
1026 if (status != APR_SUCCESS) {
1027 ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
1028 "proxy: prefetch request body failed to %pI (%s)"
1030 p_conn->addr, p_conn->hostname ? p_conn->hostname: "",
1031 c->remote_ip, c->remote_host ? c->remote_host: "");
1032 return HTTP_BAD_REQUEST;
1035 apr_brigade_length(temp_brigade, 1, &bytes);
1036 bytes_read += bytes;
1039 * Save temp_brigade in input_brigade. (At least) in the SSL case
1040 * temp_brigade contains transient buckets whose data would get
1041 * overwritten during the next call of ap_get_brigade in the loop.
1042 * ap_save_brigade ensures these buckets to be set aside.
1043 * Calling ap_save_brigade with NULL as filter is OK, because
1044 * input_brigade already has been created and does not need to get
1045 * created by ap_save_brigade.
1047 status = ap_save_brigade(NULL, &input_brigade, &temp_brigade, p);
1048 if (status != APR_SUCCESS) {
1049 ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
1050 "proxy: processing prefetched request body failed"
1051 " to %pI (%s) from %s (%s)",
1052 p_conn->addr, p_conn->hostname ? p_conn->hostname: "",
1053 c->remote_ip, c->remote_host ? c->remote_host: "");
1054 return HTTP_INTERNAL_SERVER_ERROR;
1057 /* Ensure we don't hit a wall where we have a buffer too small
1058 * for ap_get_brigade's filters to fetch us another bucket,
1059 * surrender once we hit 80 bytes less than MAX_MEM_SPOOL
1060 * (an arbitrary value.)
1062 } while ((bytes_read < MAX_MEM_SPOOL - 80)
1063 && !APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade)));
1065 /* Use chunked request body encoding or send a content-length body?
1069 * We have no request body (handled by RB_STREAM_CL)
1071 * We have a request body length <= MAX_MEM_SPOOL
1073 * The administrator has setenv force-proxy-request-1.0
1075 * The client sent a C-L body, and the administrator has
1076 * not setenv proxy-sendchunked or has set setenv proxy-sendcl
1078 * The client sent a T-E body, and the administrator has
1079 * setenv proxy-sendcl, and not setenv proxy-sendchunked
1081 * If both proxy-sendcl and proxy-sendchunked are set, the
1082 * behavior is the same as if neither were set, large bodies
1083 * that can't be read will be forwarded in their original
1084 * form of C-L, or T-E.
1086 * To ensure maximum compatibility, setenv proxy-sendcl
1087 * To reduce server resource use, setenv proxy-sendchunked
1089 * Then address specific servers with conditional setenv
1090 * options to restore the default behavior where desireable.
1092 * We have to compute content length by reading the entire request
1093 * body; if request body is not small, we'll spool the remaining
1094 * input to a temporary file. Chunked is always preferable.
1096 * We can only trust the client-provided C-L if the T-E header
1097 * is absent, and the filters are unchanged (the body won't
1098 * be resized by another content filter).
1100 if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {
1101 /* The whole thing fit, so our decision is trivial, use
1102 * the filtered bytes read from the client for the request
1103 * body Content-Length.
1105 * If we expected no body, and read no body, do not set
1106 * the Content-Length.
1108 if (old_cl_val || old_te_val || bytes_read) {
1109 old_cl_val = apr_off_t_toa(r->pool, bytes_read);
1111 rb_method = RB_STREAM_CL;
1113 else if (old_te_val) {
1115 || (apr_table_get(r->subprocess_env, "proxy-sendcl")
1116 && !apr_table_get(r->subprocess_env, "proxy-sendchunks")
1117 && !apr_table_get(r->subprocess_env, "proxy-sendchunked"))) {
1118 rb_method = RB_SPOOL_CL;
1121 rb_method = RB_STREAM_CHUNKED;
1124 else if (old_cl_val) {
1125 if (r->input_filters == r->proto_input_filters) {
1126 rb_method = RB_STREAM_CL;
1129 && (apr_table_get(r->subprocess_env, "proxy-sendchunks")
1130 || apr_table_get(r->subprocess_env, "proxy-sendchunked"))
1131 && !apr_table_get(r->subprocess_env, "proxy-sendcl")) {
1132 rb_method = RB_STREAM_CHUNKED;
1135 rb_method = RB_SPOOL_CL;
1139 /* This is an appropriate default; very efficient for no-body
1140 * requests, and has the behavior that it will not add any C-L
1141 * when the old_cl_val is NULL.
1143 rb_method = RB_SPOOL_CL;
1146 /* Yes I hate gotos. This is the subrequest shortcut */
1149 * Handle Connection: header if we do HTTP/1.1 request:
1150 * If we plan to close the backend connection sent Connection: close
1151 * otherwise sent Connection: Keep-Alive.
1154 if (p_conn->close) {
1155 buf = apr_pstrdup(p, "Connection: close" CRLF);
1158 buf = apr_pstrdup(p, "Connection: Keep-Alive" CRLF);
1160 ap_xlate_proto_to_ascii(buf, strlen(buf));
1161 e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
1162 APR_BRIGADE_INSERT_TAIL(header_brigade, e);
1165 /* send the request body, if any. */
1167 case RB_STREAM_CHUNKED:
1168 rv = stream_reqbody_chunked(p, r, p_conn, origin, header_brigade,
1172 rv = stream_reqbody_cl(p, r, p_conn, origin, header_brigade,
1173 input_brigade, old_cl_val);
1176 rv = spool_reqbody_cl(p, r, p_conn, origin, header_brigade,
1177 input_brigade, (old_cl_val != NULL)
1178 || (old_te_val != NULL)
1179 || (bytes_read > 0));
1182 /* shouldn't be possible */
1183 rv = HTTP_INTERNAL_SERVER_ERROR ;
1188 /* apr_status_t value has been logged in lower level method */
1189 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
1190 "proxy: pass request body failed to %pI (%s)"
1193 p_conn->hostname ? p_conn->hostname: "",
1195 c->remote_host ? c->remote_host: "");
1202 static void process_proxy_header(request_rec *r, proxy_dir_conf *c,
1203 const char *key, const char *value)
1205 static const char *date_hdrs[]
1206 = { "Date", "Expires", "Last-Modified", NULL };
1207 static const struct {
1209 ap_proxy_header_reverse_map_fn func;
1210 } transform_hdrs[] = {
1211 { "Location", ap_proxy_location_reverse_map },
1212 { "Content-Location", ap_proxy_location_reverse_map },
1213 { "URI", ap_proxy_location_reverse_map },
1214 { "Destination", ap_proxy_location_reverse_map },
1215 { "Set-Cookie", ap_proxy_cookie_reverse_map },
1219 for (i = 0; date_hdrs[i]; ++i) {
1220 if (!strcasecmp(date_hdrs[i], key)) {
1221 apr_table_add(r->headers_out, key,
1222 ap_proxy_date_canon(r->pool, value));
1226 for (i = 0; transform_hdrs[i].name; ++i) {
1227 if (!strcasecmp(transform_hdrs[i].name, key)) {
1228 apr_table_add(r->headers_out, key,
1229 (*transform_hdrs[i].func)(r, c, value));
1233 apr_table_add(r->headers_out, key, value);
1238 * Note: pread_len is the length of the response that we've mistakenly
1239 * read (assuming that we don't consider that an error via
1240 * ProxyBadHeader StartBody). This depends on buffer actually being
1241 * local storage to the calling code in order for pread_len to make
1242 * any sense at all, since we depend on buffer still containing
1243 * what was read by ap_getline() upon return.
1245 static void ap_proxy_read_headers(request_rec *r, request_rec *rr,
1246 char *buffer, int size,
1247 conn_rec *c, int *pread_len)
1251 char field[MAX_STRING_LEN];
1252 int saw_headers = 0;
1253 void *sconf = r->server->module_config;
1254 proxy_server_conf *psc;
1255 proxy_dir_conf *dconf;
1257 dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
1258 psc = (proxy_server_conf *) ap_get_module_config(sconf, &proxy_module);
1260 r->headers_out = apr_table_make(r->pool, 20);
1264 * Read header lines until we get the empty separator line, a read error,
1265 * the connection closes (EOF), or we timeout.
1267 ap_log_rerror(APLOG_MARK, APLOG_TRACE4, 0, r,
1268 "Headers received from backend:");
1269 while ((len = ap_getline(buffer, size, rr, 1)) > 0) {
1270 ap_log_rerror(APLOG_MARK, APLOG_TRACE4, 0, r, "%s", buffer);
1272 if (!(value = strchr(buffer, ':'))) { /* Find the colon separator */
1274 /* We may encounter invalid headers, usually from buggy
1275 * MS IIS servers, so we need to determine just how to handle
1276 * them. We can either ignore them, assume that they mark the
1277 * start-of-body (eg: a missing CRLF) or (the default) mark
1278 * the headers as totally bogus and return a 500. The sole
1279 * exception is an extra "HTTP/1.0 200, OK" line sprinkled
1280 * in between the usual MIME headers, which is a favorite
1283 /* XXX: The mask check is buggy if we ever see an HTTP/1.10 */
1285 if (!apr_date_checkmask(buffer, "HTTP/#.# ###*")) {
1286 if (psc->badopt == bad_error) {
1287 /* Nope, it wasn't even an extra HTTP header. Give up. */
1288 r->headers_out = NULL;
1291 else if (psc->badopt == bad_body) {
1292 /* if we've already started loading headers_out, then
1293 * return what we've accumulated so far, in the hopes
1294 * that they are useful; also note that we likely pre-read
1295 * the first line of the response.
1298 ap_log_error(APLOG_MARK, APLOG_WARNING, 0, r->server,
1299 "proxy: Starting body due to bogus non-header in headers "
1300 "returned by %s (%s)", r->uri, r->method);
1304 ap_log_error(APLOG_MARK, APLOG_WARNING, 0, r->server,
1305 "proxy: No HTTP headers "
1306 "returned by %s (%s)", r->uri, r->method);
1311 /* this is the psc->badopt == bad_ignore case */
1312 ap_log_error(APLOG_MARK, APLOG_WARNING, 0, r->server,
1313 "proxy: Ignoring bogus HTTP header "
1314 "returned by %s (%s)", r->uri, r->method);
1320 /* XXX: RFC2068 defines only SP and HT as whitespace, this test is
1321 * wrong... and so are many others probably.
1323 while (apr_isspace(*value))
1324 ++value; /* Skip to start of value */
1326 /* should strip trailing whitespace as well */
1327 for (end = &value[strlen(value)-1]; end > value && apr_isspace(*end); --
1331 /* make sure we add so as not to destroy duplicated headers
1332 * Modify headers requiring canonicalisation and/or affected
1333 * by ProxyPassReverse and family with process_proxy_header
1335 process_proxy_header(r, dconf, buffer, value) ;
1338 /* the header was too long; at the least we should skip extra data */
1339 if (len >= size - 1) {
1340 while ((len = ap_getline(field, MAX_STRING_LEN, rr, 1))
1341 >= MAX_STRING_LEN - 1) {
1342 /* soak up the extra data */
1344 if (len == 0) /* time to exit the larger loop as well */
1352 static int addit_dammit(void *v, const char *key, const char *val)
1354 apr_table_addn(v, key, val);
1359 apr_status_t ap_proxygetline(apr_bucket_brigade *bb, char *s, int n, request_rec *r,
1360 int fold, int *writen)
1366 rv = ap_rgetline(&tmp_s, n, &len, r, fold, bb);
1367 apr_brigade_cleanup(bb);
1369 if (rv == APR_SUCCESS) {
1370 *writen = (int) len;
1371 } else if (rv == APR_ENOSPC) {
1381 * Limit the number of interim respones we sent back to the client. Otherwise
1382 * we suffer from a memory build up. Besides there is NO sense in sending back
1383 * an unlimited number of interim responses to the client. Thus if we cross
1384 * this limit send back a 502 (Bad Gateway).
1386 #ifndef AP_MAX_INTERIM_RESPONSES
1387 #define AP_MAX_INTERIM_RESPONSES 10
1391 apr_status_t ap_proxy_http_process_response(apr_pool_t * p, request_rec *r,
1392 proxy_conn_rec **backend_ptr,
1393 proxy_worker *worker,
1394 proxy_server_conf *conf,
1395 char *server_portstr) {
1396 conn_rec *c = r->connection;
1397 char buffer[HUGE_STRING_LEN];
1401 apr_bucket_brigade *bb, *tmp_bb;
1402 apr_bucket_brigade *pass_bb;
1403 int len, backasswards;
1404 int interim_response = 0; /* non-zero whilst interim 1xx responses
1405 * are being read. */
1407 apr_table_t *save_table;
1408 int backend_broke = 0;
1409 static const char *hop_by_hop_hdrs[] =
1410 {"Keep-Alive", "Proxy-Authenticate", "TE", "Trailer", "Upgrade", NULL};
1412 const char *te = NULL;
1413 int original_status = r->status;
1414 int proxy_status = OK;
1415 const char *original_status_line = r->status_line;
1416 const char *proxy_status_line = NULL;
1417 proxy_conn_rec *backend = *backend_ptr;
1418 conn_rec *origin = backend->connection;
1419 apr_interval_time_t old_timeout = 0;
1420 proxy_dir_conf *dconf;
1421 int do_100_continue;
1423 dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
1425 do_100_continue = (worker->ping_timeout_set
1426 && ap_request_has_body(r)
1427 && (PROXYREQ_REVERSE == r->proxyreq)
1428 && !(apr_table_get(r->subprocess_env, "force-proxy-request-1.0")));
1430 bb = apr_brigade_create(p, c->bucket_alloc);
1431 pass_bb = apr_brigade_create(p, c->bucket_alloc);
1433 /* Setup for 100-Continue timeout if appropriate */
1434 if (do_100_continue) {
1435 apr_socket_timeout_get(backend->sock, &old_timeout);
1436 if (worker->ping_timeout != old_timeout) {
1438 rc = apr_socket_timeout_set(backend->sock, worker->ping_timeout);
1439 if (rc != APR_SUCCESS) {
1440 ap_log_error(APLOG_MARK, APLOG_ERR, rc, r->server,
1441 "proxy: could not set 100-Continue timeout");
1446 /* Get response from the remote server, and pass it up the
1450 backend->r = ap_proxy_make_fake_req(origin, r);
1451 /* In case anyone needs to know, this is a fake request that is really a
1454 backend->r->proxyreq = PROXYREQ_RESPONSE;
1455 tmp_bb = apr_brigade_create(p, c->bucket_alloc);
1459 apr_brigade_cleanup(bb);
1461 rc = ap_proxygetline(tmp_bb, buffer, sizeof(buffer), backend->r, 0, &len);
1463 /* handle one potential stray CRLF */
1464 rc = ap_proxygetline(tmp_bb, buffer, sizeof(buffer), backend->r, 0, &len);
1467 ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r,
1468 "proxy: error reading status line from remote "
1469 "server %s:%d", backend->hostname, backend->port);
1470 if (APR_STATUS_IS_TIMEUP(rc)) {
1471 ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1472 "proxy: read timeout");
1473 if (do_100_continue) {
1474 return ap_proxyerror(r, HTTP_SERVICE_UNAVAILABLE, "Timeout on 100-Continue");
1478 * If we are a reverse proxy request shutdown the connection
1479 * WITHOUT ANY response to trigger a retry by the client
1480 * if allowed (as for idempotent requests).
1481 * BUT currently we should not do this if the request is the
1482 * first request on a keepalive connection as browsers like
1483 * seamonkey only display an empty page in this case and do
1484 * not do a retry. We should also not do this on a
1485 * connection which times out; instead handle as
1486 * we normally would handle timeouts
1488 if (r->proxyreq == PROXYREQ_REVERSE && c->keepalives &&
1489 !APR_STATUS_IS_TIMEUP(rc)) {
1492 ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1493 "proxy: Closing connection to client because"
1494 " reading from backend server %s:%d failed."
1495 " Number of keepalives %i", backend->hostname,
1496 backend->port, c->keepalives);
1497 ap_proxy_backend_broke(r, bb);
1499 * Add an EOC bucket to signal the ap_http_header_filter
1500 * that it should get out of our way, BUT ensure that the
1501 * EOC bucket is inserted BEFORE an EOS bucket in bb as
1502 * some resource filters like mod_deflate pass everything
1503 * up to the EOS down the chain immediately and sent the
1504 * remainder of the brigade later (or even never). But in
1505 * this case the ap_http_header_filter does not get out of
1506 * our way soon enough.
1508 e = ap_bucket_eoc_create(c->bucket_alloc);
1509 eos = APR_BRIGADE_LAST(bb);
1510 while ((APR_BRIGADE_SENTINEL(bb) != eos)
1511 && !APR_BUCKET_IS_EOS(eos)) {
1512 eos = APR_BUCKET_PREV(eos);
1514 if (eos == APR_BRIGADE_SENTINEL(bb)) {
1515 APR_BRIGADE_INSERT_TAIL(bb, e);
1518 APR_BUCKET_INSERT_BEFORE(eos, e);
1520 ap_pass_brigade(r->output_filters, bb);
1521 /* Mark the backend connection for closing */
1523 /* Need to return OK to avoid sending an error message */
1526 else if (!c->keepalives) {
1527 ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1528 "proxy: NOT Closing connection to client"
1529 " although reading from backend server %s:%d"
1530 " failed.", backend->hostname,
1533 return ap_proxyerror(r, HTTP_BAD_GATEWAY,
1534 "Error reading from remote server");
1536 /* XXX: Is this a real headers length send from remote? */
1537 backend->worker->s->read += len;
1539 /* Is it an HTTP/1 response?
1540 * This is buggy if we ever see an HTTP/1.10
1542 if (apr_date_checkmask(buffer, "HTTP/#.# ###*")) {
1545 major = buffer[5] - '0';
1546 minor = buffer[7] - '0';
1548 /* If not an HTTP/1 message or
1549 * if the status line was > 8192 bytes
1551 if ((major != 1) || (len >= sizeof(buffer)-1)) {
1552 return ap_proxyerror(r, HTTP_BAD_GATEWAY,
1553 apr_pstrcat(p, "Corrupt status line returned by remote "
1554 "server: ", buffer, NULL));
1558 keepchar = buffer[12];
1560 proxy_status = atoi(&buffer[9]);
1562 if (keepchar != '\0') {
1563 buffer[12] = keepchar;
1565 /* 2616 requires the space in Status-Line; the origin
1566 * server may have sent one but ap_rgetline_core will
1567 * have stripped it. */
1571 proxy_status_line = apr_pstrdup(p, &buffer[9]);
1573 /* The status out of the front is the same as the status coming in
1574 * from the back, until further notice.
1576 r->status = proxy_status;
1577 r->status_line = proxy_status_line;
1579 ap_log_rerror(APLOG_MARK, APLOG_TRACE3, 0, r,
1580 "Status from backend: %d", proxy_status);
1582 /* read the headers. */
1583 /* N.B. for HTTP/1.0 clients, we have to fold line-wrapped headers*/
1584 /* Also, take care with headers with multiple occurences. */
1586 /* First, tuck away all already existing cookies */
1587 save_table = apr_table_make(r->pool, 2);
1588 apr_table_do(addit_dammit, save_table, r->headers_out,
1589 "Set-Cookie", NULL);
1591 /* shove the headers direct into r->headers_out */
1592 ap_proxy_read_headers(r, backend->r, buffer, sizeof(buffer), origin,
1595 if (r->headers_out == NULL) {
1596 ap_log_error(APLOG_MARK, APLOG_WARNING, 0,
1597 r->server, "proxy: bad HTTP/%d.%d header "
1598 "returned by %s (%s)", major, minor, r->uri,
1600 backend->close += 1;
1602 * ap_send_error relies on a headers_out to be present. we
1603 * are in a bad position here.. so force everything we send out
1604 * to have nothing to do with the incoming packet
1606 r->headers_out = apr_table_make(r->pool,1);
1607 r->status = HTTP_BAD_GATEWAY;
1608 r->status_line = "bad gateway";
1612 /* Now, add in the just read cookies */
1613 apr_table_do(addit_dammit, save_table, r->headers_out,
1614 "Set-Cookie", NULL);
1616 /* and now load 'em all in */
1617 if (!apr_is_empty_table(save_table)) {
1618 apr_table_unset(r->headers_out, "Set-Cookie");
1619 r->headers_out = apr_table_overlay(r->pool,
1624 /* can't have both Content-Length and Transfer-Encoding */
1625 if (apr_table_get(r->headers_out, "Transfer-Encoding")
1626 && apr_table_get(r->headers_out, "Content-Length")) {
1628 * 2616 section 4.4, point 3: "if both Transfer-Encoding
1629 * and Content-Length are received, the latter MUST be
1632 * To help mitigate HTTP Splitting, unset Content-Length
1633 * and shut down the backend server connection
1634 * XXX: We aught to treat such a response as uncachable
1636 apr_table_unset(r->headers_out, "Content-Length");
1637 ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
1638 "proxy: server %s:%d returned Transfer-Encoding"
1639 " and Content-Length", backend->hostname,
1641 backend->close += 1;
1645 * Save a possible Transfer-Encoding header as we need it later for
1646 * ap_http_filter to know where to end.
1648 te = apr_table_get(r->headers_out, "Transfer-Encoding");
1649 /* strip connection listed hop-by-hop headers from response */
1650 backend->close += ap_proxy_liststr(apr_table_get(r->headers_out,
1653 ap_proxy_clear_connection(p, r->headers_out);
1654 if ((buf = apr_table_get(r->headers_out, "Content-Type"))) {
1655 ap_set_content_type(r, apr_pstrdup(p, buf));
1657 if (!ap_is_HTTP_INFO(proxy_status)) {
1658 ap_proxy_pre_http_request(origin, backend->r);
1661 /* Clear hop-by-hop headers */
1662 for (i=0; hop_by_hop_hdrs[i]; ++i) {
1663 apr_table_unset(r->headers_out, hop_by_hop_hdrs[i]);
1665 /* Delete warnings with wrong date */
1666 r->headers_out = ap_proxy_clean_warnings(p, r->headers_out);
1668 /* handle Via header in response */
1669 if (conf->viaopt != via_off && conf->viaopt != via_block) {
1670 const char *server_name = ap_get_server_name(r);
1671 /* If USE_CANONICAL_NAME_OFF was configured for the proxy virtual host,
1672 * then the server name returned by ap_get_server_name() is the
1673 * origin server name (which does make too much sense with Via: headers)
1674 * so we use the proxy vhost's name instead.
1676 if (server_name == r->hostname)
1677 server_name = r->server->server_hostname;
1678 /* create a "Via:" response header entry and merge it */
1679 apr_table_addn(r->headers_out, "Via",
1680 (conf->viaopt == via_full)
1681 ? apr_psprintf(p, "%d.%d %s%s (%s)",
1682 HTTP_VERSION_MAJOR(r->proto_num),
1683 HTTP_VERSION_MINOR(r->proto_num),
1686 AP_SERVER_BASEVERSION)
1687 : apr_psprintf(p, "%d.%d %s%s",
1688 HTTP_VERSION_MAJOR(r->proto_num),
1689 HTTP_VERSION_MINOR(r->proto_num),
1695 /* cancel keepalive if HTTP/1.0 or less */
1696 if ((major < 1) || (minor < 1)) {
1697 backend->close += 1;
1698 origin->keepalive = AP_CONN_CLOSE;
1701 /* an http/0.9 response */
1704 r->status_line = "200 OK";
1705 backend->close += 1;
1708 if (ap_is_HTTP_INFO(proxy_status)) {
1710 /* Reset to old timeout iff we've adjusted it */
1712 && (r->status == HTTP_CONTINUE)
1713 && (worker->ping_timeout != old_timeout)) {
1714 apr_socket_timeout_set(backend->sock, old_timeout);
1718 interim_response = 0;
1720 if (interim_response) {
1721 /* RFC2616 tells us to forward this.
1723 * OTOH, an interim response here may mean the backend
1724 * is playing sillybuggers. The Client didn't ask for
1725 * it within the defined HTTP/1.1 mechanisms, and if
1726 * it's an extension, it may also be unsupported by us.
1728 * There's also the possibility that changing existing
1729 * behaviour here might break something.
1731 * So let's make it configurable.
1733 const char *policy = apr_table_get(r->subprocess_env,
1734 "proxy-interim-response");
1735 ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
1736 "proxy: HTTP: received interim %d response",
1738 if (!policy || !strcasecmp(policy, "RFC")) {
1739 ap_send_interim_response(r, 1);
1741 /* FIXME: refine this to be able to specify per-response-status
1742 * policies and maybe also add option to bail out with 502
1744 else if (strcasecmp(policy, "Suppress")) {
1745 ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,
1746 "undefined proxy interim response policy");
1749 /* Moved the fixups of Date headers and those affected by
1750 * ProxyPassReverse/etc from here to ap_proxy_read_headers
1753 if ((proxy_status == 401) && (dconf->error_override)) {
1755 const char *wa = "WWW-Authenticate";
1756 if ((buf = apr_table_get(r->headers_out, wa))) {
1757 apr_table_set(r->err_headers_out, wa, buf);
1759 ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
1760 "proxy: origin server sent 401 without WWW-Authenticate header");
1766 * Is it an HTTP/0.9 response or did we maybe preread the 1st line of
1767 * the response? If so, load the extra data. These are 2 mutually
1768 * exclusive possibilities, that just happen to require very
1771 if (backasswards || pread_len) {
1772 apr_ssize_t cntr = (apr_ssize_t)pread_len;
1775 * At this point in response processing of a 0.9 response,
1776 * we don't know yet whether data is binary or not.
1777 * mod_charset_lite will get control later on, so it cannot
1778 * decide on the conversion of this buffer full of data.
1779 * However, chances are that we are not really talking to an
1780 * HTTP/0.9 server, but to some different protocol, therefore
1781 * the best guess IMHO is to always treat the buffer as "text/x":
1783 ap_xlate_proto_to_ascii(buffer, len);
1784 cntr = (apr_ssize_t)len;
1786 e = apr_bucket_heap_create(buffer, cntr, NULL, c->bucket_alloc);
1787 APR_BRIGADE_INSERT_TAIL(bb, e);
1789 /* PR 41646: get HEAD right with ProxyErrorOverride */
1790 if (ap_is_HTTP_ERROR(r->status) && dconf->error_override) {
1791 /* clear r->status for override error, otherwise ErrorDocument
1792 * thinks that this is a recursive error, and doesn't find the
1795 r->status = HTTP_OK;
1796 /* Discard body, if one is expected */
1797 if (!r->header_only && /* not HEAD request */
1798 (proxy_status != HTTP_NO_CONTENT) && /* not 204 */
1799 (proxy_status != HTTP_NOT_MODIFIED)) { /* not 304 */
1800 ap_discard_request_body(backend->r);
1802 return proxy_status;
1805 /* send body - but only if a body is expected */
1806 if ((!r->header_only) && /* not HEAD request */
1807 !interim_response && /* not any 1xx response */
1808 (proxy_status != HTTP_NO_CONTENT) && /* not 204 */
1809 (proxy_status != HTTP_NOT_MODIFIED)) { /* not 304 */
1811 /* We need to copy the output headers and treat them as input
1812 * headers as well. BUT, we need to do this before we remove
1813 * TE, so that they are preserved accordingly for
1814 * ap_http_filter to know where to end.
1816 backend->r->headers_in = apr_table_clone(backend->r->pool, r->headers_out);
1818 * Restore Transfer-Encoding header from response if we saved
1819 * one before and there is none left. We need it for the
1820 * ap_http_filter. See above.
1822 if (te && !apr_table_get(backend->r->headers_in, "Transfer-Encoding")) {
1823 apr_table_add(backend->r->headers_in, "Transfer-Encoding", te);
1826 apr_table_unset(r->headers_out,"Transfer-Encoding");
1828 ap_log_error(APLOG_MARK, APLOG_TRACE3, 0, r->server,
1829 "proxy: start body send");
1832 * if we are overriding the errors, we can't put the content
1833 * of the page into the brigade
1835 if (!dconf->error_override || !ap_is_HTTP_ERROR(proxy_status)) {
1836 /* read the body, pass it to the output filters */
1837 apr_read_type_e mode = APR_NONBLOCK_READ;
1840 /* Handle the case where the error document is itself reverse
1841 * proxied and was successful. We must maintain any previous
1842 * error status so that an underlying error (eg HTTP_NOT_FOUND)
1843 * doesn't become an HTTP_OK.
1845 if (dconf->error_override && !ap_is_HTTP_ERROR(proxy_status)
1846 && ap_is_HTTP_ERROR(original_status)) {
1847 r->status = original_status;
1848 r->status_line = original_status_line;
1852 apr_off_t readbytes;
1855 rv = ap_get_brigade(backend->r->input_filters, bb,
1856 AP_MODE_READBYTES, mode,
1857 conf->io_buffer_size);
1859 /* ap_get_brigade will return success with an empty brigade
1860 * for a non-blocking read which would block: */
1861 if (APR_STATUS_IS_EAGAIN(rv)
1862 || (rv == APR_SUCCESS && APR_BRIGADE_EMPTY(bb))) {
1863 /* flush to the client and switch to blocking mode */
1864 e = apr_bucket_flush_create(c->bucket_alloc);
1865 APR_BRIGADE_INSERT_TAIL(bb, e);
1866 if (ap_pass_brigade(r->output_filters, bb)
1871 apr_brigade_cleanup(bb);
1872 mode = APR_BLOCK_READ;
1875 else if (rv == APR_EOF) {
1878 else if (rv != APR_SUCCESS) {
1879 /* In this case, we are in real trouble because
1880 * our backend bailed on us. Pass along a 502 error
1883 ap_log_cerror(APLOG_MARK, APLOG_ERR, rv, c,
1884 "proxy: error reading response");
1885 ap_proxy_backend_broke(r, bb);
1886 ap_pass_brigade(r->output_filters, bb);
1891 /* next time try a non-blocking read */
1892 mode = APR_NONBLOCK_READ;
1894 apr_brigade_length(bb, 0, &readbytes);
1895 backend->worker->s->read += readbytes;
1898 ap_log_error(APLOG_MARK, APLOG_DEBUG, 0,
1899 r->server, "proxy (PID %d): readbytes: %#x",
1900 getpid(), readbytes);
1904 if (APR_BRIGADE_EMPTY(bb)) {
1905 apr_brigade_cleanup(bb);
1909 /* Switch the allocator lifetime of the buckets */
1910 ap_proxy_buckets_lifetime_transform(r, bb, pass_bb);
1912 /* found the last brigade? */
1913 if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(pass_bb))) {
1915 /* signal that we must leave */
1918 /* the brigade may contain transient buckets that contain
1919 * data that lives only as long as the backend connection.
1920 * Force a setaside so these transient buckets become heap
1921 * buckets that live as long as the request.
1923 for (e = APR_BRIGADE_FIRST(pass_bb); e
1924 != APR_BRIGADE_SENTINEL(pass_bb); e
1925 = APR_BUCKET_NEXT(e)) {
1926 apr_bucket_setaside(e, r->pool);
1929 /* finally it is safe to clean up the brigade from the
1930 * connection pool, as we have forced a setaside on all
1933 apr_brigade_cleanup(bb);
1935 /* make sure we release the backend connection as soon
1936 * as we know we are done, so that the backend isn't
1937 * left waiting for a slow client to eventually
1938 * acknowledge the data.
1940 ap_proxy_release_connection(backend->worker->scheme,
1941 backend, r->server);
1942 /* Ensure that the backend is not reused */
1943 *backend_ptr = NULL;
1947 /* try send what we read */
1948 if (ap_pass_brigade(r->output_filters, pass_bb) != APR_SUCCESS
1950 /* Ack! Phbtt! Die! User aborted! */
1951 /* Only close backend if we haven't got all from the
1952 * backend. Furthermore if *backend_ptr is NULL it is no
1953 * longer save to fiddle around with backend as it might
1954 * be already in use by another thread.
1957 backend->close = 1; /* this causes socket close below */
1962 /* make sure we always clean up after ourselves */
1963 apr_brigade_cleanup(pass_bb);
1964 apr_brigade_cleanup(bb);
1968 ap_log_error(APLOG_MARK, APLOG_TRACE2, 0, r->server,
1969 "proxy: end body send");
1971 else if (!interim_response) {
1972 ap_log_error(APLOG_MARK, APLOG_TRACE2, 0, r->server,
1973 "proxy: header only");
1975 /* make sure we release the backend connection as soon
1976 * as we know we are done, so that the backend isn't
1977 * left waiting for a slow client to eventually
1978 * acknowledge the data.
1980 ap_proxy_release_connection(backend->worker->scheme,
1981 backend, r->server);
1982 *backend_ptr = NULL;
1984 /* Pass EOS bucket down the filter chain. */
1985 e = apr_bucket_eos_create(c->bucket_alloc);
1986 APR_BRIGADE_INSERT_TAIL(bb, e);
1987 ap_pass_brigade(r->output_filters, bb);
1989 apr_brigade_cleanup(bb);
1991 } while (interim_response && (interim_response < AP_MAX_INTERIM_RESPONSES));
1993 /* See define of AP_MAX_INTERIM_RESPONSES for why */
1994 if (interim_response >= AP_MAX_INTERIM_RESPONSES) {
1995 return ap_proxyerror(r, HTTP_BAD_GATEWAY,
1997 "Too many (%d) interim responses from origin server",
2001 /* If our connection with the client is to be aborted, return DONE. */
2002 if (c->aborted || backend_broke) {
2010 apr_status_t ap_proxy_http_cleanup(const char *scheme, request_rec *r,
2011 proxy_conn_rec *backend)
2013 ap_proxy_release_connection(scheme, backend, r->server);
2018 * This handles http:// URLs, and other URLs using a remote proxy over http
2019 * If proxyhost is NULL, then contact the server directly, otherwise
2021 * Note that if a proxy is used, then URLs other than http: can be accessed,
2022 * also, if we have trouble which is clearly specific to the proxy, then
2023 * we return DECLINED so that we can try another proxy. (Or the direct
2026 static int proxy_http_handler(request_rec *r, proxy_worker *worker,
2027 proxy_server_conf *conf,
2028 char *url, const char *proxyname,
2029 apr_port_t proxyport)
2032 char server_portstr[32];
2034 const char *proxy_function;
2036 proxy_conn_rec *backend = NULL;
2038 conn_rec *c = r->connection;
2041 * Use a shorter-lived pool to reduce memory usage
2042 * and avoid a memory leak
2044 apr_pool_t *p = r->pool;
2045 apr_uri_t *uri = apr_palloc(p, sizeof(*uri));
2047 /* find the scheme */
2048 u = strchr(url, ':');
2049 if (u == NULL || u[1] != '/' || u[2] != '/' || u[3] == '\0')
2052 return HTTP_BAD_REQUEST;
2053 scheme = apr_pstrndup(p, url, u - url);
2054 /* scheme is lowercase */
2055 ap_str_tolower(scheme);
2057 if (strcmp(scheme, "https") == 0) {
2058 if (!ap_proxy_ssl_enable(NULL)) {
2059 ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
2060 "proxy: HTTPS: declining URL %s"
2061 " (mod_ssl not configured?)", url);
2065 proxy_function = "HTTPS";
2067 else if (!(strcmp(scheme, "http") == 0 || (strcmp(scheme, "ftp") == 0 && proxyname))) {
2068 ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
2069 "proxy: HTTP: declining URL %s", url);
2070 return DECLINED; /* only interested in HTTP, or FTP via proxy */
2074 proxy_function = "HTTP";
2076 proxy_function = "FTP";
2078 ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, r->server,
2079 "proxy: HTTP: serving URL %s", url);
2082 /* create space for state information */
2083 if ((status = ap_proxy_acquire_connection(proxy_function, &backend,
2084 worker, r->server)) != OK)
2088 backend->is_ssl = is_ssl;
2091 ap_proxy_ssl_connection_cleanup(backend, r);
2095 * In the case that we are handling a reverse proxy connection and this
2096 * is not a request that is coming over an already kept alive connection
2097 * with the client, do NOT reuse the connection to the backend, because
2098 * we cannot forward a failure to the client in this case as the client
2099 * does NOT expect this in this situation.
2100 * Yes, this creates a performance penalty.
2102 if ((r->proxyreq == PROXYREQ_REVERSE) && (!c->keepalives)
2103 && (apr_table_get(r->subprocess_env, "proxy-initial-not-pooled"))) {
2110 /* Step One: Determine Who To Connect To */
2111 if ((status = ap_proxy_determine_connection(p, r, conf, worker, backend,
2112 uri, &locurl, proxyname,
2113 proxyport, server_portstr,
2114 sizeof(server_portstr))) != OK)
2117 /* Step Two: Make the Connection */
2118 if (ap_proxy_connect_backend(proxy_function, backend, worker, r->server)) {
2119 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
2120 "proxy: HTTP: failed to make connection to backend: %s",
2122 status = HTTP_SERVICE_UNAVAILABLE;
2126 /* Step Three: Create conn_rec */
2127 if (!backend->connection) {
2128 if ((status = ap_proxy_connection_create(proxy_function, backend,
2129 c, r->server)) != OK)
2132 * On SSL connections set a note on the connection what CN is
2133 * requested, such that mod_ssl can check if it is requested to do
2137 apr_table_set(backend->connection->notes, "proxy-request-hostname",
2142 /* Step Four: Send the Request
2143 * On the off-chance that we forced a 100-Continue as a
2144 * kinda HTTP ping test, allow for retries
2146 if ((status = ap_proxy_http_request(p, r, backend, worker,
2147 conf, uri, locurl, server_portstr)) != OK) {
2148 if ((status == HTTP_SERVICE_UNAVAILABLE) && worker->ping_timeout_set) {
2150 ap_log_error(APLOG_MARK, APLOG_INFO, status, r->server,
2151 "proxy: HTTP: 100-Continue failed to %pI (%s)",
2152 worker->cp->addr, worker->hostname);
2161 /* Step Five: Receive the Response... Fall thru to cleanup */
2162 status = ap_proxy_http_process_response(p, r, &backend, worker,
2163 conf, server_portstr);
2168 /* Step Six: Clean Up */
2173 ap_proxy_http_cleanup(proxy_function, r, backend);
2177 static void ap_proxy_http_register_hook(apr_pool_t *p)
2179 proxy_hook_scheme_handler(proxy_http_handler, NULL, NULL, APR_HOOK_FIRST);
2180 proxy_hook_canon_handler(proxy_http_canon, NULL, NULL, APR_HOOK_FIRST);
2181 warn_rx = ap_pregcomp(p, "[0-9]{3}[ \t]+[^ \t]+[ \t]+\"[^\"]*\"([ \t]+\"([^\"]+)\")?", 0);
2184 AP_DECLARE_MODULE(proxy_http) = {
2185 STANDARD20_MODULE_STUFF,
2186 NULL, /* create per-directory config structure */
2187 NULL, /* merge per-directory config structures */
2188 NULL, /* create per-server config structure */
2189 NULL, /* merge per-server config structures */
2190 NULL, /* command apr_table_t */
2191 ap_proxy_http_register_hook/* register hooks */