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.
22 * @brief Proxy Extension Module for Apache
24 * @defgroup MOD_PROXY mod_proxy
25 * @ingroup APACHE_MODS
31 Also note numerous FIXMEs and CHECKMEs which should be eliminated.
35 #include "apr_hooks.h"
38 #include "apr_strings.h"
39 #include "apr_buckets.h"
41 #include "apr_network_io.h"
42 #include "apr_pools.h"
43 #include "apr_strings.h"
46 #include "apr_strmatch.h"
47 #include "apr_fnmatch.h"
48 #include "apr_reslist.h"
49 #define APR_WANT_STRFUNC
53 #include "http_config.h"
54 #include "ap_config.h"
55 #include "http_core.h"
56 #include "http_protocol.h"
57 #include "http_request.h"
58 #include "http_vhost.h"
59 #include "http_main.h"
61 #include "http_connection.h"
62 #include "util_filter.h"
63 #include "util_ebcdic.h"
64 #include "ap_provider.h"
66 #if APR_HAVE_NETINET_IN_H
67 #include <netinet/in.h>
69 #if APR_HAVE_ARPA_INET_H
70 #include <arpa/inet.h>
73 /* for proxy_canonenc() */
75 enc_path, enc_search, enc_user, enc_fpath, enc_parm
78 #if APR_CHARSET_EBCDIC
80 #else /*APR_CHARSET_EBCDIC*/
81 #define CRLF "\015\012"
82 #endif /*APR_CHARSET_EBCDIC*/
84 /* default Max-Forwards header setting */
85 /* Set this to -1, which complies with RFC2616 by not setting
86 * max-forwards if the client didn't send it to us.
88 #define DEFAULT_MAX_FORWARDS -1
90 /* static information about a remote proxy */
92 const char *scheme; /* the schemes handled by this proxy, or '*' */
93 const char *protocol; /* the scheme used to talk to this proxy */
94 const char *hostname; /* the hostname of this proxy */
95 apr_port_t port; /* the port for this proxy */
96 ap_regex_t *regexp; /* compiled regex (if any) for the remote */
97 int use_regex; /* simple boolean. True if we have a regex pattern */
100 #define PROXYPASS_NOCANON 0x01
101 #define PROXYPASS_INTERPOLATE 0x02
109 struct dirconn_entry {
111 struct in_addr addr, mask;
112 struct apr_sockaddr_t *hostaddr;
113 int (*matcher) (struct dirconn_entry * This, request_rec *r);
116 struct noproxy_entry {
118 struct apr_sockaddr_t *addr;
121 typedef struct proxy_balancer proxy_balancer;
122 typedef struct proxy_worker proxy_worker;
123 typedef struct proxy_conn_pool proxy_conn_pool;
124 typedef struct proxy_balancer_method proxy_balancer_method;
127 apr_array_header_t *proxies;
128 apr_array_header_t *sec_proxy;
129 apr_array_header_t *aliases;
130 apr_array_header_t *noproxies;
131 apr_array_header_t *dirconn;
132 apr_array_header_t *workers;
133 apr_array_header_t *balancers;
134 proxy_worker *forward; /* forward proxy worker */
135 proxy_worker *reverse; /* reverse "module-driven" proxy worker */
136 const char *domain; /* domain name to use in absence of a domain name in the request */
137 int req; /* true if proxy requests are enabled */
144 } viaopt; /* how to deal with proxy Via: headers */
146 apr_size_t recv_buffer_size;
147 char recv_buffer_size_set;
148 apr_size_t io_buffer_size;
149 char io_buffer_size_set;
153 * the following setting masks the error page
154 * returned from the 'proxied server' and just
155 * forwards the status code upwards.
156 * This allows the main server (us) to generate
157 * the error page, (so it will look like a error
158 * returned from the rest of the system
161 int error_override_set;
162 apr_interval_time_t timeout;
168 } badopt; /* how to deal with bad headers */
170 /* putting new stuff on the end maximises binary back-compatibility.
171 * the strmatch_patterns are really a const just to have a
172 * case-independent strstr.
178 } proxy_status; /* Status display options */
179 char proxy_status_set;
180 apr_pool_t *pool; /* Pool used for allocating this struct */
185 const char *p; /* The path */
186 int p_is_fnmatch; /* Is this path an fnmatch candidate? */
187 ap_regex_t *r; /* Is this a regex? */
189 /* ProxyPassReverse and friends are documented as working inside
190 * <Location>. But in fact they never have done in the case of
191 * more than one <Location>, because the server_conf can't see it.
192 * We need to move them to the per-dir config.
193 * Discussed in February:
194 * http://marc.theaimsgroup.com/?l=apache-httpd-dev&m=110726027118798&w=2
196 apr_array_header_t *raliases;
197 apr_array_header_t* cookie_paths;
198 apr_array_header_t* cookie_domains;
199 const apr_strmatch_pattern* cookie_path_str;
200 const apr_strmatch_pattern* cookie_domain_str;
203 int preserve_host_set;
206 /* if we interpolate env vars per-request, we'll need a per-request
207 * copy of the reverse proxy config
210 apr_array_header_t *raliases;
211 apr_array_header_t* cookie_paths;
212 apr_array_header_t* cookie_domains;
216 conn_rec *connection;
217 const char *hostname;
220 apr_pool_t *pool; /* Subpool for hostname and addr data */
221 apr_socket_t *sock; /* Connection socket */
222 apr_sockaddr_t *addr; /* Preparsed remote address info */
223 apr_uint32_t flags; /* Connection flags */
224 int close; /* Close 'this' connection */
225 proxy_worker *worker; /* Connection pool this connection belongs to */
226 void *data; /* per scheme connection data */
228 int inreslist; /* connection in apr_reslist? */
230 apr_pool_t *scpool; /* Subpool used for socket and connection data */
231 request_rec *r; /* Request record of the frontend request
232 * which the backend currently answers. */
233 int need_flush;/* Flag to decide whether we need to flush the
234 * filter chain or not */
235 void *forward; /* opaque forward proxy data */
239 float cache_completion; /* completion percentage */
240 int content_length; /* length of the content */
243 /* Connection pool */
244 struct proxy_conn_pool {
245 apr_pool_t *pool; /* The pool used in constructor and destructor calls */
246 apr_sockaddr_t *addr; /* Preparsed remote address info */
248 apr_reslist_t *res; /* Connection resource list */
250 proxy_conn_rec *conn; /* Single connection for prefork mpm's */
253 /* worker status flags */
254 #define PROXY_WORKER_INITIALIZED 0x0001
255 #define PROXY_WORKER_IGNORE_ERRORS 0x0002
256 #define PROXY_WORKER_IN_SHUTDOWN 0x0010
257 #define PROXY_WORKER_DISABLED 0x0020
258 #define PROXY_WORKER_STOPPED 0x0040
259 #define PROXY_WORKER_IN_ERROR 0x0080
260 #define PROXY_WORKER_HOT_STANDBY 0x0100
262 #define PROXY_WORKER_NOT_USABLE_BITMAP ( PROXY_WORKER_IN_SHUTDOWN | \
263 PROXY_WORKER_DISABLED | PROXY_WORKER_STOPPED | PROXY_WORKER_IN_ERROR )
265 /* NOTE: these check the shared status */
266 #define PROXY_WORKER_IS_INITIALIZED(f) ( (f)->s && \
267 ( (f)->s->status & PROXY_WORKER_INITIALIZED ) )
269 #define PROXY_WORKER_IS_STANDBY(f) ( (f)->s && \
270 ( (f)->s->status & PROXY_WORKER_HOT_STANDBY ) )
272 #define PROXY_WORKER_IS_USABLE(f) ( (f)->s && \
273 ( !( (f)->s->status & PROXY_WORKER_NOT_USABLE_BITMAP) ) && \
274 PROXY_WORKER_IS_INITIALIZED(f) )
276 /* default worker retry timeout in seconds */
277 #define PROXY_WORKER_DEFAULT_RETRY 60
278 #define PROXY_WORKER_MAX_ROUTE_SIZ 63
280 /* Runtime worker status informations. Shared in scoreboard */
283 apr_time_t error_time; /* time of the last error */
284 int retries; /* number of retries on this worker */
285 int lbstatus; /* Current lbstatus */
286 int lbfactor; /* dynamic lbfactor */
287 apr_off_t transferred;/* Number of bytes transferred to remote */
288 apr_off_t read; /* Number of bytes read from remote */
289 apr_size_t elected; /* Number of times the worker was elected */
290 char route[PROXY_WORKER_MAX_ROUTE_SIZ+1];
291 char redirect[PROXY_WORKER_MAX_ROUTE_SIZ+1];
292 void *context; /* general purpose storage */
293 apr_size_t busy; /* busyness factor */
294 int lbset; /* load balancer cluster set */
297 /* Worker configuration */
298 struct proxy_worker {
299 int id; /* scoreboard id */
300 apr_interval_time_t retry; /* retry interval */
301 int lbfactor; /* initial load balancing factor */
303 const char *scheme; /* scheme to use ajp|http|https */
304 const char *hostname; /* remote backend address */
305 const char *route; /* balancing route */
306 const char *redirect; /* temporary balancing redirection route */
307 int status; /* temporary worker status */
309 int min; /* Desired minimum number of available connections */
310 int smax; /* Soft maximum on the total number of connections */
311 int hmax; /* Hard maximum on the total number of connections */
312 apr_interval_time_t ttl; /* maximum amount of time in seconds a connection
313 * may be available while exceeding the soft limit */
314 apr_interval_time_t timeout; /* connection timeout */
316 apr_interval_time_t acquire; /* acquire timeout when the maximum number of connections is exceeded */
318 apr_size_t recv_buffer_size;
319 char recv_buffer_size_set;
320 apr_size_t io_buffer_size;
321 char io_buffer_size_set;
324 proxy_conn_pool *cp; /* Connection pool to use */
325 proxy_worker_stat *s; /* Shared data */
326 void *opaque; /* per scheme worker data */
327 int is_address_reusable;
329 apr_thread_mutex_t *mutex; /* Thread lock for updating address cache */
331 void *context; /* general purpose storage */
336 } flush_packets; /* control AJP flushing */
337 int flush_wait; /* poll wait time in microseconds if flush_auto */
338 apr_interval_time_t ping_timeout;
339 char ping_timeout_set;
340 int lbset; /* load balancer cluster set */
343 char disablereuse_set;
344 apr_interval_time_t conn_timeout;
345 char conn_timeout_set;
346 const char *flusher; /* flush provider used by mod_proxy_fdpass */
350 * Wait 10000 microseconds to find out if more data is currently
351 * available at the backend. Just an arbitrary choose.
353 #define PROXY_FLUSH_WAIT 10000
355 struct proxy_balancer {
356 apr_array_header_t *workers; /* array of proxy_workers */
357 const char *name; /* name of the load balancer */
358 const char *sticky; /* sticky session identifier */
359 int sticky_force; /* Disable failover for sticky sessions */
360 apr_interval_time_t timeout; /* Timeout for waiting on free connection */
361 int max_attempts; /* Number of attempts before failing */
362 char max_attempts_set;
363 proxy_balancer_method *lbmethod;
365 /* XXX: Perhaps we will need the proc mutex too.
366 * Altrough we are only using arithmetic operations
367 * it may lead to a incorrect calculations.
368 * For now use only the thread mutex.
371 apr_thread_mutex_t *mutex; /* Thread lock for updating lb params */
373 void *context; /* general purpose storage */
374 const char *sticky_path; /* URL sticky session identifier */
375 int scolonsep; /* true if ';' seps sticky session paths */
376 apr_array_header_t *errstatuses; /* statuses to force members into error */
379 struct proxy_balancer_method {
380 const char *name; /* name of the load balancer method*/
381 proxy_worker *(*finder)(proxy_balancer *balancer,
383 void *context; /* general purpose storage */
384 apr_status_t (*reset)(proxy_balancer *balancer, server_rec *s);
385 apr_status_t (*age)(proxy_balancer *balancer, server_rec *s);
389 #define PROXY_THREAD_LOCK(x) apr_thread_mutex_lock((x)->mutex)
390 #define PROXY_THREAD_UNLOCK(x) apr_thread_mutex_unlock((x)->mutex)
392 #define PROXY_THREAD_LOCK(x) APR_SUCCESS
393 #define PROXY_THREAD_UNLOCK(x) APR_SUCCESS
398 /* Create a set of PROXY_DECLARE(type), PROXY_DECLARE_NONSTD(type) and
399 * PROXY_DECLARE_DATA with appropriate export and import tags for the platform
402 #define PROXY_DECLARE(type) type
403 #define PROXY_DECLARE_NONSTD(type) type
404 #define PROXY_DECLARE_DATA
405 #elif defined(PROXY_DECLARE_STATIC)
406 #define PROXY_DECLARE(type) type __stdcall
407 #define PROXY_DECLARE_NONSTD(type) type
408 #define PROXY_DECLARE_DATA
409 #elif defined(PROXY_DECLARE_EXPORT)
410 #define PROXY_DECLARE(type) __declspec(dllexport) type __stdcall
411 #define PROXY_DECLARE_NONSTD(type) __declspec(dllexport) type
412 #define PROXY_DECLARE_DATA __declspec(dllexport)
414 #define PROXY_DECLARE(type) __declspec(dllimport) type __stdcall
415 #define PROXY_DECLARE_NONSTD(type) __declspec(dllimport) type
416 #define PROXY_DECLARE_DATA __declspec(dllimport)
420 * Hook an optional proxy hook. Unlike static hooks, this uses a macro
421 * instead of a function.
423 #define PROXY_OPTIONAL_HOOK(name,fn,pre,succ,order) \
424 APR_OPTIONAL_HOOK(proxy,name,fn,pre,succ,order)
426 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, scheme_handler, (request_rec *r,
427 proxy_worker *worker, proxy_server_conf *conf, char *url,
428 const char *proxyhost, apr_port_t proxyport))
429 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, canon_handler, (request_rec *r,
432 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, create_req, (request_rec *r, request_rec *pr))
433 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, fixups, (request_rec *r))
437 * It will return the most suitable worker at the moment
438 * and coresponding balancer.
439 * The url is rewritten from balancer://cluster/uri to scheme://host:port/uri
440 * and then the scheme_handler is called.
443 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, pre_request, (proxy_worker **worker,
444 proxy_balancer **balancer,
446 proxy_server_conf *conf, char **url))
449 * It is called after request for updating runtime balancer status.
451 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, post_request, (proxy_worker *worker,
452 proxy_balancer *balancer, request_rec *r,
453 proxy_server_conf *conf))
456 * request status hook
457 * It is called after all proxy processing has been done. This gives other
458 * modules a chance to create default content on failure, for example
460 APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, request_status,
461 (int *status, request_rec *r))
465 PROXY_DECLARE(request_rec *)ap_proxy_make_fake_req(conn_rec *c, request_rec *r);
466 PROXY_DECLARE(int) ap_proxy_hex2c(const char *x);
467 PROXY_DECLARE(void) ap_proxy_c2hex(int ch, char *x);
468 PROXY_DECLARE(char *)ap_proxy_canonenc(apr_pool_t *p, const char *x, int len, enum enctype t,
469 int forcedec, int proxyreq);
470 PROXY_DECLARE(char *)ap_proxy_canon_netloc(apr_pool_t *p, char **const urlp, char **userp,
471 char **passwordp, char **hostp, apr_port_t *port);
472 PROXY_DECLARE(const char *)ap_proxy_date_canon(apr_pool_t *p, const char *x);
473 PROXY_DECLARE(int) ap_proxy_liststr(const char *list, const char *val);
474 PROXY_DECLARE(char *)ap_proxy_removestr(apr_pool_t *pool, const char *list, const char *val);
475 PROXY_DECLARE(int) ap_proxy_hex2sec(const char *x);
476 PROXY_DECLARE(void) ap_proxy_sec2hex(int t, char *y);
477 PROXY_DECLARE(int) ap_proxyerror(request_rec *r, int statuscode, const char *message);
478 PROXY_DECLARE(int) ap_proxy_is_ipaddr(struct dirconn_entry *This, apr_pool_t *p);
479 PROXY_DECLARE(int) ap_proxy_is_domainname(struct dirconn_entry *This, apr_pool_t *p);
480 PROXY_DECLARE(int) ap_proxy_is_hostname(struct dirconn_entry *This, apr_pool_t *p);
481 PROXY_DECLARE(int) ap_proxy_is_word(struct dirconn_entry *This, apr_pool_t *p);
482 PROXY_DECLARE(int) ap_proxy_checkproxyblock(request_rec *r, proxy_server_conf *conf, apr_sockaddr_t *uri_addr);
483 PROXY_DECLARE(int) ap_proxy_pre_http_request(conn_rec *c, request_rec *r);
484 PROXY_DECLARE(apr_status_t) ap_proxy_string_read(conn_rec *c, apr_bucket_brigade *bb, char *buff, size_t bufflen, int *eos);
485 PROXY_DECLARE(void) ap_proxy_table_unmerge(apr_pool_t *p, apr_table_t *t, char *key);
486 /* DEPRECATED (will be replaced with ap_proxy_connect_backend */
487 PROXY_DECLARE(int) ap_proxy_connect_to_backend(apr_socket_t **, const char *, apr_sockaddr_t *, const char *, proxy_server_conf *, server_rec *, apr_pool_t *);
488 PROXY_DECLARE(apr_status_t) ap_proxy_ssl_connection_cleanup(proxy_conn_rec *conn,
490 PROXY_DECLARE(int) ap_proxy_ssl_enable(conn_rec *c);
491 PROXY_DECLARE(int) ap_proxy_ssl_disable(conn_rec *c);
492 PROXY_DECLARE(int) ap_proxy_conn_is_https(conn_rec *c);
493 PROXY_DECLARE(const char *) ap_proxy_ssl_val(apr_pool_t *p, server_rec *s, conn_rec *c, request_rec *r, const char *var);
495 /* Header mapping functions, and a typedef of their signature */
496 PROXY_DECLARE(const char *) ap_proxy_location_reverse_map(request_rec *r, proxy_dir_conf *conf, const char *url);
497 PROXY_DECLARE(const char *) ap_proxy_cookie_reverse_map(request_rec *r, proxy_dir_conf *conf, const char *str);
500 typedef const char *(*ap_proxy_header_reverse_map_fn)(request_rec *,
501 proxy_dir_conf *, const char *);
502 #elif defined(PROXY_DECLARE_STATIC)
503 typedef const char *(__stdcall *ap_proxy_header_reverse_map_fn)(request_rec *,
504 proxy_dir_conf *, const char *);
505 #elif defined(PROXY_DECLARE_EXPORT)
506 typedef __declspec(dllexport) const char *
507 (__stdcall *ap_proxy_header_reverse_map_fn)(request_rec *,
508 proxy_dir_conf *, const char *);
510 typedef __declspec(dllimport) const char *
511 (__stdcall *ap_proxy_header_reverse_map_fn)(request_rec *,
512 proxy_dir_conf *, const char *);
516 /* Connection pool API */
518 * Get the worker from proxy configuration
519 * @param p memory pool used for finding worker
520 * @param conf current proxy server configuration
521 * @param url url to find the worker from
522 * @return proxy_worker or NULL if not found
524 PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker(apr_pool_t *p,
525 proxy_server_conf *conf,
528 * Add the worker to proxy configuration
529 * @param worker the new worker
530 * @param p memory pool to allocate worker from
531 * @param conf current proxy server configuration
532 * @param url url containing worker name
533 * @return error message or NULL if successfull
535 PROXY_DECLARE(const char *) ap_proxy_add_worker(proxy_worker **worker,
537 proxy_server_conf *conf,
542 * @param p memory pool to allocate worker from
545 PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker(apr_pool_t *p);
548 * Initize the worker's shared data
549 * @param conf current proxy server configuration
550 * @param worker worker to initialize
551 * @param s current server record
552 * @param worker worker to initialize
554 PROXY_DECLARE(void) ap_proxy_initialize_worker_share(proxy_server_conf *conf,
555 proxy_worker *worker,
561 * @param worker worker to initialize
562 * @param s current server record
563 * @param p memory pool used for mutex and Connection pool.
564 * @return APR_SUCCESS or error code
566 PROXY_DECLARE(apr_status_t) ap_proxy_initialize_worker(proxy_worker *worker,
570 * Get the balancer from proxy configuration
571 * @param p memory pool used for finding balancer
572 * @param conf current proxy server configuration
573 * @param url url to find the worker from. Has to have balancer:// prefix
574 * @return proxy_balancer or NULL if not found
576 PROXY_DECLARE(proxy_balancer *) ap_proxy_get_balancer(apr_pool_t *p,
577 proxy_server_conf *conf,
580 * Add the balancer to proxy configuration
581 * @param balancer the new balancer
582 * @param p memory pool to allocate balancer from
583 * @param conf current proxy server configuration
584 * @param url url containing balancer name
585 * @return error message or NULL if successfull
587 PROXY_DECLARE(const char *) ap_proxy_add_balancer(proxy_balancer **balancer,
589 proxy_server_conf *conf,
593 * Add the worker to the balancer
594 * @param pool memory pool for adding worker
595 * @param balancer balancer to add to
596 * @param worker worker to add
597 * @note Single worker can be added to multiple balancers.
599 PROXY_DECLARE(void) ap_proxy_add_worker_to_balancer(apr_pool_t *pool,
600 proxy_balancer *balancer,
601 proxy_worker *worker);
603 * Get the most suitable worker and(or) balancer for the request
604 * @param worker worker used for processing request
605 * @param balancer balancer used for processing request
606 * @param r current request
607 * @param conf current proxy server configuration
608 * @param url request url that balancer can rewrite.
609 * @return OK or HTTP_XXX error
610 * @note It calls balancer pre_request hook if the url starts with balancer://
611 * The balancer then rewrites the url to particular worker, like http://host:port
613 PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker,
614 proxy_balancer **balancer,
616 proxy_server_conf *conf,
619 * Post request worker and balancer cleanup
620 * @param worker worker used for processing request
621 * @param balancer balancer used for processing request
622 * @param r current request
623 * @param conf current proxy server configuration
624 * @return OK or HTTP_XXX error
625 * @note When ever the pre_request is called, the post_request has to be
628 PROXY_DECLARE(int) ap_proxy_post_request(proxy_worker *worker,
629 proxy_balancer *balancer,
631 proxy_server_conf *conf);
634 * Request status function
635 * @param status status of proxy request (result)
636 * @param r the request to obtain the status for
637 * @return OK or DECLINED
639 PROXY_DECLARE(int) ap_proxy_request_status(int *status, request_rec *r);
642 * Deternime backend hostname and port
643 * @param p memory pool used for processing
644 * @param r current request
645 * @param conf current proxy server configuration
646 * @param worker worker used for processing request
647 * @param conn proxy connection struct
648 * @param uri processed uri
649 * @param url request url
650 * @param proxyname are we connecting directly or via s proxy
651 * @param proxyport proxy host port
652 * @param server_portstr Via headers server port
653 * @param server_portstr_size size of the server_portstr buffer
654 * @return OK or HTTP_XXX error
656 PROXY_DECLARE(int) ap_proxy_determine_connection(apr_pool_t *p, request_rec *r,
657 proxy_server_conf *conf,
658 proxy_worker *worker,
659 proxy_conn_rec *conn,
662 const char *proxyname,
663 apr_port_t proxyport,
664 char *server_portstr,
665 int server_portstr_size);
668 * Mark a worker for retry
669 * @param proxy_function calling proxy scheme (http, ajp, ...)
670 * @param worker worker used for retrying
671 * @param s current server record
672 * @return OK if marked for retry, DECLINED otherwise
673 * @note Worker will be marker for retry if the time of the last retry
674 * has been ellapsed. In case there is no retry option set, defaults to
675 * number_of_retries seconds.
677 PROXY_DECLARE(int) ap_proxy_retry_worker(const char *proxy_function,
678 proxy_worker *worker,
681 * Acquire a connection from workers connection pool
682 * @param proxy_function calling proxy scheme (http, ajp, ...)
683 * @param conn acquired connection
684 * @param worker worker used for obtaining connection
685 * @param s current server record
686 * @return OK or HTTP_XXX error
687 * @note If the number of connections is exhaused the function will
688 * block untill the timeout is reached.
690 PROXY_DECLARE(int) ap_proxy_acquire_connection(const char *proxy_function,
691 proxy_conn_rec **conn,
692 proxy_worker *worker,
695 * Release a connection back to worker connection pool
696 * @param proxy_function calling proxy scheme (http, ajp, ...)
697 * @param conn acquired connection
698 * @param s current server record
699 * @return OK or HTTP_XXX error
700 * @note The connection will be closed if conn->close_on_release is set
702 PROXY_DECLARE(int) ap_proxy_release_connection(const char *proxy_function,
703 proxy_conn_rec *conn,
706 * Make a connection to the backend
707 * @param proxy_function calling proxy scheme (http, ajp, ...)
708 * @param conn acquired connection
709 * @param worker connection worker
710 * @param s current server record
711 * @return OK or HTTP_XXX error
712 * @note In case the socket already exists for conn, just check the link
715 PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function,
716 proxy_conn_rec *conn,
717 proxy_worker *worker,
720 * Make a connection record for backend connection
721 * @param proxy_function calling proxy scheme (http, ajp, ...)
722 * @param conn acquired connection
723 * @param c client connection record
724 * @param s current server record
725 * @return OK or HTTP_XXX error
727 PROXY_DECLARE(int) ap_proxy_connection_create(const char *proxy_function,
728 proxy_conn_rec *conn,
729 conn_rec *c, server_rec *s);
731 * Signal the upstream chain that the connection to the backend broke in the
732 * middle of the response. This is done by sending an error bucket with
733 * status HTTP_BAD_GATEWAY and an EOS bucket up the filter chain.
734 * @param r current request record of client request
735 * @param brigade The brigade that is sent through the output filter chain
737 PROXY_DECLARE(void) ap_proxy_backend_broke(request_rec *r,
738 apr_bucket_brigade *brigade);
741 * Transform buckets from one bucket allocator to another one by creating a
742 * transient bucket for each data bucket and let it use the data read from
743 * the old bucket. Metabuckets are transformed by just recreating them.
744 * Attention: Currently only the following bucket types are handled:
750 * If an other bucket type is found its type is logged as a debug message
751 * and APR_EGENERAL is returned.
752 * @param r current request record of client request. Only used for logging
754 * @param from the brigade that contains the buckets to transform
755 * @param to the brigade that will receive the transformed buckets
756 * @return APR_SUCCESS if all buckets could be transformed APR_EGENERAL
759 PROXY_DECLARE(apr_status_t)
760 ap_proxy_buckets_lifetime_transform(request_rec *r, apr_bucket_brigade *from,
761 apr_bucket_brigade *to);
763 #define PROXY_LBMETHOD "proxylbmethod"
765 /* The number of dynamic workers that can be added when reconfiguring.
766 * If this limit is reached you must stop and restart the server.
768 #define PROXY_DYNAMIC_BALANCER_LIMIT 16
770 * Calculate number of maximum number of workers in scoreboard.
771 * @return number of workers to allocate in the scoreboard
773 int ap_proxy_lb_workers(void);
776 extern module PROXY_DECLARE_DATA proxy_module;
778 extern int PROXY_DECLARE_DATA proxy_lb_workers;
780 #endif /*MOD_PROXY_H*/