mod_proxy.h revision 96a068a3b179bd57a0935ea50384756845b8b271
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef MOD_PROXY_H
#define MOD_PROXY_H
/**
* @file mod_proxy.h
* @brief Proxy Extension Module for Apache
*
* @defgroup MOD_PROXY mod_proxy
* @ingroup APACHE_MODS
* @{
*/
/*
Also note numerous FIXMEs and CHECKMEs which should be eliminated.
*/
#include "apr_hooks.h"
#include "apr.h"
#include "apr_lib.h"
#include "apr_strings.h"
#include "apr_buckets.h"
#include "apr_md5.h"
#include "apr_network_io.h"
#include "apr_pools.h"
#include "apr_strings.h"
#include "apr_uri.h"
#include "apr_date.h"
#include "apr_strmatch.h"
#include "apr_fnmatch.h"
#include "apr_reslist.h"
#define APR_WANT_STRFUNC
#include "apr_want.h"
#include "httpd.h"
#include "http_config.h"
#include "ap_config.h"
#include "http_core.h"
#include "http_protocol.h"
#include "http_request.h"
#include "http_vhost.h"
#include "http_main.h"
#include "http_log.h"
#include "http_connection.h"
#include "util_filter.h"
#include "util_ebcdic.h"
#include "ap_provider.h"
#if APR_HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if APR_HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
/* for proxy_canonenc() */
enum enctype {
enc_path, enc_search, enc_user, enc_fpath, enc_parm
};
#if APR_CHARSET_EBCDIC
#define CRLF "\r\n"
#else /*APR_CHARSET_EBCDIC*/
#define CRLF "\015\012"
#endif /*APR_CHARSET_EBCDIC*/
/* default Max-Forwards header setting */
/* Set this to -1, which complies with RFC2616 by not setting
* max-forwards if the client didn't send it to us.
*/
#define DEFAULT_MAX_FORWARDS -1
/* static information about a remote proxy */
struct proxy_remote {
const char *scheme; /* the schemes handled by this proxy, or '*' */
const char *protocol; /* the scheme used to talk to this proxy */
const char *hostname; /* the hostname of this proxy */
ap_regex_t *regexp; /* compiled regex (if any) for the remote */
int use_regex; /* simple boolean. True if we have a regex pattern */
apr_port_t port; /* the port for this proxy */
};
#define PROXYPASS_NOCANON 0x01
#define PROXYPASS_INTERPOLATE 0x02
struct proxy_alias {
const char *real;
const char *fake;
ap_regex_t *regex;
unsigned int flags;
};
struct dirconn_entry {
char *name;
struct in_addr addr, mask;
struct apr_sockaddr_t *hostaddr;
int (*matcher) (struct dirconn_entry * This, request_rec *r);
};
struct noproxy_entry {
const char *name;
struct apr_sockaddr_t *addr;
};
typedef struct proxy_balancer proxy_balancer;
typedef struct proxy_worker proxy_worker;
typedef struct proxy_conn_pool proxy_conn_pool;
typedef struct proxy_balancer_method proxy_balancer_method;
typedef struct {
apr_array_header_t *proxies;
apr_array_header_t *sec_proxy;
apr_array_header_t *aliases;
apr_array_header_t *noproxies;
apr_array_header_t *dirconn;
apr_array_header_t *workers;
apr_array_header_t *balancers;
proxy_worker *forward; /* forward proxy worker */
proxy_worker *reverse; /* reverse "module-driven" proxy worker */
const char *domain; /* domain name to use in absence of a domain name in the request */
apr_pool_t *pool; /* Pool used for allocating this struct */
int req; /* true if proxy requests are enabled */
enum {
via_off,
via_on,
via_block,
via_full
} viaopt; /* how to deal with proxy Via: headers */
apr_size_t recv_buffer_size;
apr_size_t io_buffer_size;
long maxfwd;
apr_interval_time_t timeout;
enum {
bad_error,
bad_ignore,
bad_body
} badopt; /* how to deal with bad headers */
enum {
status_off,
status_on,
status_full
} proxy_status; /* Status display options */
int req_set:1;
int viaopt_set:1;
int recv_buffer_size_set:1;
int io_buffer_size_set:1;
int maxfwd_set:1;
int timeout_set:1;
int badopt_set:1;
int proxy_status_set:1;
} proxy_server_conf;
typedef struct {
const char *p; /* The path */
ap_regex_t *r; /* Is this a regex? */
/* ProxyPassReverse and friends are documented as working inside
* <Location>. But in fact they never have done in the case of
* more than one <Location>, because the server_conf can't see it.
* We need to move them to the per-dir config.
* Discussed in February:
* http://marc.theaimsgroup.com/?l=apache-httpd-dev&m=110726027118798&w=2
*/
apr_array_header_t *raliases;
apr_array_header_t* cookie_paths;
apr_array_header_t* cookie_domains;
const apr_strmatch_pattern* cookie_path_str;
const apr_strmatch_pattern* cookie_domain_str;
signed char p_is_fnmatch; /* Is the path an fnmatch candidate? */
signed char interpolate_env;
struct proxy_alias *alias;
/**
* the following setting masks the error page
* returned from the 'proxied server' and just
* forwards the status code upwards.
* This allows the main server (us) to generate
* the error page, (so it will look like a error
* returned from the rest of the system
*/
int error_override:1;
int preserve_host:1;
int preserve_host_set:1;
int error_override_set:1;
int alias_set:1;
} proxy_dir_conf;
/* if we interpolate env vars per-request, we'll need a per-request
* copy of the reverse proxy config
*/
typedef struct {
apr_array_header_t *raliases;
apr_array_header_t* cookie_paths;
apr_array_header_t* cookie_domains;
} proxy_req_conf;
typedef struct {
conn_rec *connection;
request_rec *r; /* Request record of the frontend request
* which the backend currently answers. */
proxy_worker *worker; /* Connection pool this connection belongs to */
apr_pool_t *pool; /* Subpool for hostname and addr data */
const char *hostname;
apr_sockaddr_t *addr; /* Preparsed remote address info */
apr_pool_t *scpool; /* Subpool used for socket and connection data */
apr_socket_t *sock; /* Connection socket */
void *data; /* per scheme connection data */
void *forward; /* opaque forward proxy data */
apr_uint32_t flags; /* Connection flags */
apr_port_t port;
int is_ssl:1;
int close:1; /* Close 'this' connection */
int need_flush:1; /* Flag to decide whether we need to flush the
* filter chain or not */
#if APR_HAS_THREADS
int inreslist:1; /* connection in apr_reslist? */
#endif
int cleaned:1; /* connection cleaned? */
} proxy_conn_rec;
typedef struct {
float cache_completion; /* completion percentage */
int content_length; /* length of the content */
} proxy_completion;
/* Connection pool */
struct proxy_conn_pool {
apr_pool_t *pool; /* The pool used in constructor and destructor calls */
apr_sockaddr_t *addr; /* Preparsed remote address info */
#if APR_HAS_THREADS
apr_reslist_t *res; /* Connection resource list */
#endif
proxy_conn_rec *conn; /* Single connection for prefork mpm's */
};
/* worker status flags */
#define PROXY_WORKER_INITIALIZED 0x0001
#define PROXY_WORKER_IGNORE_ERRORS 0x0002
#define PROXY_WORKER_DRAIN 0x0004
#define PROXY_WORKER_IN_SHUTDOWN 0x0010
#define PROXY_WORKER_DISABLED 0x0020
#define PROXY_WORKER_STOPPED 0x0040
#define PROXY_WORKER_IN_ERROR 0x0080
#define PROXY_WORKER_HOT_STANDBY 0x0100
#define PROXY_WORKER_FREE 0x0200
#define PROXY_WORKER_NOT_USABLE_BITMAP ( PROXY_WORKER_IN_SHUTDOWN | \
PROXY_WORKER_DISABLED | PROXY_WORKER_STOPPED | PROXY_WORKER_IN_ERROR )
/* NOTE: these check the shared status */
#define PROXY_WORKER_IS_INITIALIZED(f) ( (f)->s && \
( (f)->s->status & PROXY_WORKER_INITIALIZED ) )
#define PROXY_WORKER_IS_STANDBY(f) ( (f)->s && \
( (f)->s->status & PROXY_WORKER_HOT_STANDBY ) )
#define PROXY_WORKER_IS_USABLE(f) ( (f)->s && \
( !( (f)->s->status & PROXY_WORKER_NOT_USABLE_BITMAP) ) && \
PROXY_WORKER_IS_INITIALIZED(f) )
/* default worker retry timeout in seconds */
#define PROXY_WORKER_DEFAULT_RETRY 60
#define PROXY_WORKER_MAX_ROUTE_SIZ 63
/* Runtime worker status informations. Shared in scoreboard */
typedef struct {
apr_time_t error_time; /* time of the last error */
int status;
int retries; /* number of retries on this worker */
int lbstatus; /* Current lbstatus */
int lbfactor; /* dynamic lbfactor */
apr_off_t transferred;/* Number of bytes transferred to remote */
apr_off_t read; /* Number of bytes read from remote */
apr_size_t elected; /* Number of times the worker was elected */
char route[PROXY_WORKER_MAX_ROUTE_SIZ+1];
char redirect[PROXY_WORKER_MAX_ROUTE_SIZ+1];
void *context; /* general purpose storage */
apr_size_t busy; /* busyness factor */
int lbset; /* load balancer cluster set */
unsigned int apr_hash; /* hash #0 of worker name */
unsigned int our_hash; /* hash #1 of worker name. Why 2? hash collisions. */
} proxy_worker_stat;
/* Worker configuration */
struct proxy_worker {
const char *name;
const char *scheme; /* scheme to use ajp|http|https */
const char *hostname; /* remote backend address */
const char *route; /* balancing route */
const char *redirect; /* temporary balancing redirection route */
int id; /* scoreboard id */
int status; /* temporary worker status */
int lbfactor; /* initial load balancing factor */
int lbset; /* load balancer cluster set */
int min; /* Desired minimum number of available connections */
int smax; /* Soft maximum on the total number of connections */
int hmax; /* Hard maximum on the total number of connections */
apr_interval_time_t ttl; /* maximum amount of time in seconds a connection
* may be available while exceeding the soft limit */
apr_interval_time_t retry; /* retry interval */
apr_interval_time_t timeout; /* connection timeout */
apr_interval_time_t acquire; /* acquire timeout when the maximum number of connections is exceeded */
apr_interval_time_t ping_timeout;
apr_interval_time_t conn_timeout;
apr_size_t recv_buffer_size;
apr_size_t io_buffer_size;
apr_port_t port;
char keepalive;
char disablereuse;
int is_address_reusable:1;
proxy_conn_pool *cp; /* Connection pool to use */
proxy_worker_stat *s; /* Shared data */
void *opaque; /* per scheme worker data */
void *context; /* general purpose storage */
enum {
flush_off,
flush_on,
flush_auto
} flush_packets; /* control AJP flushing */
int flush_wait; /* poll wait time in microseconds if flush_auto */
const char *flusher; /* flush provider used by mod_proxy_fdpass */
#if APR_HAS_THREADS
apr_thread_mutex_t *mutex; /* Thread lock for updating address cache */
#endif
int retry_set:1;
int timeout_set:1;
int acquire_set:1;
int ping_timeout_set:1;
int conn_timeout_set:1;
int recv_buffer_size_set:1;
int io_buffer_size_set:1;
int keepalive_set:1;
int disablereuse_set:1;
unsigned int apr_hash; /* hash #0 of worker name */
unsigned int our_hash; /* hash #1 of worker name. Why 2? hash collisions. */
};
/*
* Wait 10000 microseconds to find out if more data is currently
* available at the backend. Just an arbitrary choose.
*/
#define PROXY_FLUSH_WAIT 10000
struct proxy_balancer {
apr_array_header_t *workers; /* array of proxy_workers */
const char *name; /* name of the load balancer */
apr_interval_time_t timeout; /* Timeout for waiting on free connection */
proxy_balancer_method *lbmethod;
const char *sticky_path; /* URL sticky session identifier */
apr_array_header_t *errstatuses; /* statuses to force members into error */
const char *sticky; /* sticky session identifier */
int max_attempts; /* Number of attempts before failing */
int sticky_force:1; /* Disable failover for sticky sessions */
int scolonsep:1; /* true if ';' seps sticky session paths */
int max_attempts_set:1;
/* XXX: Perhaps we will need the proc mutex too.
* Altrough we are only using arithmetic operations
* it may lead to a incorrect calculations.
* For now use only the thread mutex.
*/
#if APR_HAS_THREADS
apr_thread_mutex_t *mutex; /* Thread lock for updating lb params */
#endif
void *context; /* general purpose storage */
apr_time_t updated; /* timestamp of last update */
};
struct proxy_balancer_method {
const char *name; /* name of the load balancer method*/
proxy_worker *(*finder)(proxy_balancer *balancer,
request_rec *r);
void *context; /* general purpose storage */
apr_status_t (*reset)(proxy_balancer *balancer, server_rec *s);
apr_status_t (*age)(proxy_balancer *balancer, server_rec *s);
apr_status_t (*updatelbstatus)(proxy_balancer *balancer, proxy_worker *elected, server_rec *s);
};
#if APR_HAS_THREADS
#define PROXY_THREAD_LOCK(x) apr_thread_mutex_lock((x)->mutex)
#define PROXY_THREAD_UNLOCK(x) apr_thread_mutex_unlock((x)->mutex)
#else
#define PROXY_THREAD_LOCK(x) APR_SUCCESS
#define PROXY_THREAD_UNLOCK(x) APR_SUCCESS
#endif
/* hooks */
/* Create a set of PROXY_DECLARE(type), PROXY_DECLARE_NONSTD(type) and
* PROXY_DECLARE_DATA with appropriate export and import tags for the platform
*/
#if !defined(WIN32)
#define PROXY_DECLARE(type) type
#define PROXY_DECLARE_NONSTD(type) type
#define PROXY_DECLARE_DATA
#elif defined(PROXY_DECLARE_STATIC)
#define PROXY_DECLARE(type) type __stdcall
#define PROXY_DECLARE_NONSTD(type) type
#define PROXY_DECLARE_DATA
#elif defined(PROXY_DECLARE_EXPORT)
#define PROXY_DECLARE(type) __declspec(dllexport) type __stdcall
#define PROXY_DECLARE_NONSTD(type) __declspec(dllexport) type
#define PROXY_DECLARE_DATA __declspec(dllexport)
#else
#define PROXY_DECLARE(type) __declspec(dllimport) type __stdcall
#define PROXY_DECLARE_NONSTD(type) __declspec(dllimport) type
#define PROXY_DECLARE_DATA __declspec(dllimport)
#endif
/**
* Hook an optional proxy hook. Unlike static hooks, this uses a macro
* instead of a function.
*/
#define PROXY_OPTIONAL_HOOK(name,fn,pre,succ,order) \
APR_OPTIONAL_HOOK(proxy,name,fn,pre,succ,order)
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, scheme_handler, (request_rec *r,
proxy_worker *worker, proxy_server_conf *conf, char *url,
const char *proxyhost, apr_port_t proxyport))
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, canon_handler, (request_rec *r,
char *url))
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, create_req, (request_rec *r, request_rec *pr))
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, fixups, (request_rec *r))
/**
* pre request hook.
* It will return the most suitable worker at the moment
* and coresponding balancer.
* The url is rewritten from balancer://cluster/uri to scheme://host:port/uri
* and then the scheme_handler is called.
*
*/
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, pre_request, (proxy_worker **worker,
proxy_balancer **balancer,
request_rec *r,
proxy_server_conf *conf, char **url))
/**
* post request hook.
* It is called after request for updating runtime balancer status.
*/
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, post_request, (proxy_worker *worker,
proxy_balancer *balancer, request_rec *r,
proxy_server_conf *conf))
/**
* request status hook
* It is called after all proxy processing has been done. This gives other
* modules a chance to create default content on failure, for example
*/
APR_DECLARE_EXTERNAL_HOOK(proxy, PROXY, int, request_status,
(int *status, request_rec *r))
/* proxy_util.c */
PROXY_DECLARE(request_rec *)ap_proxy_make_fake_req(conn_rec *c, request_rec *r);
PROXY_DECLARE(int) ap_proxy_hex2c(const char *x);
PROXY_DECLARE(void) ap_proxy_c2hex(int ch, char *x);
PROXY_DECLARE(char *)ap_proxy_canonenc(apr_pool_t *p, const char *x, int len, enum enctype t,
int forcedec, int proxyreq);
PROXY_DECLARE(char *)ap_proxy_canon_netloc(apr_pool_t *p, char **const urlp, char **userp,
char **passwordp, char **hostp, apr_port_t *port);
PROXY_DECLARE(const char *)ap_proxy_date_canon(apr_pool_t *p, const char *x);
PROXY_DECLARE(int) ap_proxy_liststr(const char *list, const char *val);
PROXY_DECLARE(char *)ap_proxy_removestr(apr_pool_t *pool, const char *list, const char *val);
PROXY_DECLARE(int) ap_proxy_hex2sec(const char *x);
PROXY_DECLARE(void) ap_proxy_sec2hex(int t, char *y);
PROXY_DECLARE(int) ap_proxyerror(request_rec *r, int statuscode, const char *message);
PROXY_DECLARE(int) ap_proxy_is_ipaddr(struct dirconn_entry *This, apr_pool_t *p);
PROXY_DECLARE(int) ap_proxy_is_domainname(struct dirconn_entry *This, apr_pool_t *p);
PROXY_DECLARE(int) ap_proxy_is_hostname(struct dirconn_entry *This, apr_pool_t *p);
PROXY_DECLARE(int) ap_proxy_is_word(struct dirconn_entry *This, apr_pool_t *p);
PROXY_DECLARE(int) ap_proxy_checkproxyblock(request_rec *r, proxy_server_conf *conf, apr_sockaddr_t *uri_addr);
PROXY_DECLARE(int) ap_proxy_pre_http_request(conn_rec *c, request_rec *r);
PROXY_DECLARE(apr_status_t) ap_proxy_string_read(conn_rec *c, apr_bucket_brigade *bb, char *buff, size_t bufflen, int *eos);
PROXY_DECLARE(void) ap_proxy_table_unmerge(apr_pool_t *p, apr_table_t *t, char *key);
/* DEPRECATED (will be replaced with ap_proxy_connect_backend */
PROXY_DECLARE(int) ap_proxy_connect_to_backend(apr_socket_t **, const char *, apr_sockaddr_t *, const char *, proxy_server_conf *, request_rec *);
PROXY_DECLARE(apr_status_t) ap_proxy_ssl_connection_cleanup(proxy_conn_rec *conn,
request_rec *r);
PROXY_DECLARE(int) ap_proxy_ssl_enable(conn_rec *c);
PROXY_DECLARE(int) ap_proxy_ssl_disable(conn_rec *c);
PROXY_DECLARE(int) ap_proxy_conn_is_https(conn_rec *c);
PROXY_DECLARE(const char *) ap_proxy_ssl_val(apr_pool_t *p, server_rec *s, conn_rec *c, request_rec *r, const char *var);
/* Header mapping functions, and a typedef of their signature */
PROXY_DECLARE(const char *) ap_proxy_location_reverse_map(request_rec *r, proxy_dir_conf *conf, const char *url);
PROXY_DECLARE(const char *) ap_proxy_cookie_reverse_map(request_rec *r, proxy_dir_conf *conf, const char *str);
#if !defined(WIN32)
typedef const char *(*ap_proxy_header_reverse_map_fn)(request_rec *,
proxy_dir_conf *, const char *);
#elif defined(PROXY_DECLARE_STATIC)
typedef const char *(__stdcall *ap_proxy_header_reverse_map_fn)(request_rec *,
proxy_dir_conf *, const char *);
#elif defined(PROXY_DECLARE_EXPORT)
typedef __declspec(dllexport) const char *
(__stdcall *ap_proxy_header_reverse_map_fn)(request_rec *,
proxy_dir_conf *, const char *);
#else
typedef __declspec(dllimport) const char *
(__stdcall *ap_proxy_header_reverse_map_fn)(request_rec *,
proxy_dir_conf *, const char *);
#endif
/* Connection pool API */
/**
* Get the worker from proxy configuration
* @param p memory pool used for finding worker
* @param conf current proxy server configuration
* @param url url to find the worker from
* @return proxy_worker or NULL if not found
*/
PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker(apr_pool_t *p,
proxy_server_conf *conf,
const char *url);
/**
* Add the worker to proxy configuration
* @param worker the new worker
* @param p memory pool to allocate worker from
* @param conf current proxy server configuration
* @param url url containing worker name
* @param id slotnumber id or -1 for auto allocation
* @return error message or NULL if successfull
*/
PROXY_DECLARE(const char *) ap_proxy_add_worker_wid(proxy_worker **worker,
apr_pool_t *p,
proxy_server_conf *conf,
const char *url,
int id);
/**
* Add the worker to proxy configuration
* @param worker the new worker
* @param p memory pool to allocate worker from
* @param conf current proxy server configuration
* @param url url containing worker name
* @return error message or NULL if successfull
*/
PROXY_DECLARE(const char *) ap_proxy_add_worker(proxy_worker **worker,
apr_pool_t *p,
proxy_server_conf *conf,
const char *url);
/**
* Create new worker
* @param p memory pool to allocate worker from
* @param id slotnumber id or -1 for auto allocation
* @return new worker
*/
PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker_wid(apr_pool_t *p, int id);
/**
* Create new worker
* @param p memory pool to allocate worker from
* @return new worker
*/
PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker(apr_pool_t *p);
/**
* Initize the worker's shared data
* @param conf current proxy server configuration
* @param worker worker to initialize
* @param s current server record
* @param worker worker to initialize
*/
PROXY_DECLARE(void) ap_proxy_initialize_worker_share(proxy_server_conf *conf,
proxy_worker *worker,
server_rec *s);
/**
* Initize the worker
* @param worker worker to initialize
* @param s current server record
* @param p memory pool used for mutex and Connection pool.
* @return APR_SUCCESS or error code
*/
PROXY_DECLARE(apr_status_t) ap_proxy_initialize_worker(proxy_worker *worker,
server_rec *s,
apr_pool_t *p);
/**
* Get the balancer from proxy configuration
* @param p memory pool used for finding balancer
* @param conf current proxy server configuration
* @param url url to find the worker from. Has to have balancer:// prefix
* @return proxy_balancer or NULL if not found
*/
PROXY_DECLARE(proxy_balancer *) ap_proxy_get_balancer(apr_pool_t *p,
proxy_server_conf *conf,
const char *url);
/**
* Add the balancer to proxy configuration
* @param balancer the new balancer
* @param p memory pool to allocate balancer from
* @param conf current proxy server configuration
* @param url url containing balancer name
* @return error message or NULL if successfull
*/
PROXY_DECLARE(const char *) ap_proxy_add_balancer(proxy_balancer **balancer,
apr_pool_t *p,
proxy_server_conf *conf,
const char *url);
/**
* Add the worker to the balancer
* @param pool memory pool for adding worker
* @param balancer balancer to add to
* @param worker worker to add
* @param id slotnumber id or -1 for auto allocation
* @note Single worker can be added to multiple balancers.
*/
PROXY_DECLARE(void) ap_proxy_add_worker_to_balancer_wid(apr_pool_t *pool,
proxy_balancer *balancer,
proxy_worker *worker,
int id);
/**
* Add the worker to the balancer
* @param pool memory pool for adding worker
* @param balancer balancer to add to
* @param worker worker to add
* @note Single worker can be added to multiple balancers.
*/
PROXY_DECLARE(void) ap_proxy_add_worker_to_balancer(apr_pool_t *pool,
proxy_balancer *balancer,
proxy_worker *worker);
/**
* Get the most suitable worker and(or) balancer for the request
* @param worker worker used for processing request
* @param balancer balancer used for processing request
* @param r current request
* @param conf current proxy server configuration
* @param url request url that balancer can rewrite.
* @return OK or HTTP_XXX error
* @note It calls balancer pre_request hook if the url starts with balancer://
* The balancer then rewrites the url to particular worker, like http://host:port
*/
PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker,
proxy_balancer **balancer,
request_rec *r,
proxy_server_conf *conf,
char **url);
/**
* Post request worker and balancer cleanup
* @param worker worker used for processing request
* @param balancer balancer used for processing request
* @param r current request
* @param conf current proxy server configuration
* @return OK or HTTP_XXX error
* @note When ever the pre_request is called, the post_request has to be
* called too.
*/
PROXY_DECLARE(int) ap_proxy_post_request(proxy_worker *worker,
proxy_balancer *balancer,
request_rec *r,
proxy_server_conf *conf);
/**
* Request status function
* @param status status of proxy request (result)
* @param r the request to obtain the status for
* @return OK or DECLINED
*/
PROXY_DECLARE(int) ap_proxy_request_status(int *status, request_rec *r);
/**
* Deternime backend hostname and port
* @param p memory pool used for processing
* @param r current request
* @param conf current proxy server configuration
* @param worker worker used for processing request
* @param conn proxy connection struct
* @param uri processed uri
* @param url request url
* @param proxyname are we connecting directly or via s proxy
* @param proxyport proxy host port
* @param server_portstr Via headers server port
* @param server_portstr_size size of the server_portstr buffer
* @return OK or HTTP_XXX error
*/
PROXY_DECLARE(int) ap_proxy_determine_connection(apr_pool_t *p, request_rec *r,
proxy_server_conf *conf,
proxy_worker *worker,
proxy_conn_rec *conn,
apr_uri_t *uri,
char **url,
const char *proxyname,
apr_port_t proxyport,
char *server_portstr,
int server_portstr_size);
/**
* Mark a worker for retry
* @param proxy_function calling proxy scheme (http, ajp, ...)
* @param worker worker used for retrying
* @param s current server record
* @return OK if marked for retry, DECLINED otherwise
* @note Worker will be marker for retry if the time of the last retry
* has been ellapsed. In case there is no retry option set, defaults to
* number_of_retries seconds.
*/
PROXY_DECLARE(int) ap_proxy_retry_worker(const char *proxy_function,
proxy_worker *worker,
server_rec *s);
/**
* Acquire a connection from workers connection pool
* @param proxy_function calling proxy scheme (http, ajp, ...)
* @param conn acquired connection
* @param worker worker used for obtaining connection
* @param s current server record
* @return OK or HTTP_XXX error
* @note If the number of connections is exhaused the function will
* block untill the timeout is reached.
*/
PROXY_DECLARE(int) ap_proxy_acquire_connection(const char *proxy_function,
proxy_conn_rec **conn,
proxy_worker *worker,
server_rec *s);
/**
* Release a connection back to worker connection pool
* @param proxy_function calling proxy scheme (http, ajp, ...)
* @param conn acquired connection
* @param s current server record
* @return OK or HTTP_XXX error
* @note The connection will be closed if conn->close_on_release is set
*/
PROXY_DECLARE(int) ap_proxy_release_connection(const char *proxy_function,
proxy_conn_rec *conn,
server_rec *s);
/**
* Make a connection to the backend
* @param proxy_function calling proxy scheme (http, ajp, ...)
* @param conn acquired connection
* @param worker connection worker
* @param s current server record
* @return OK or HTTP_XXX error
* @note In case the socket already exists for conn, just check the link
* status.
*/
PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function,
proxy_conn_rec *conn,
proxy_worker *worker,
server_rec *s);
/**
* Make a connection record for backend connection
* @param proxy_function calling proxy scheme (http, ajp, ...)
* @param conn acquired connection
* @param c client connection record
* @param s current server record
* @return OK or HTTP_XXX error
*/
PROXY_DECLARE(int) ap_proxy_connection_create(const char *proxy_function,
proxy_conn_rec *conn,
conn_rec *c, server_rec *s);
/**
* Signal the upstream chain that the connection to the backend broke in the
* middle of the response. This is done by sending an error bucket with
* status HTTP_BAD_GATEWAY and an EOS bucket up the filter chain.
* @param r current request record of client request
* @param brigade The brigade that is sent through the output filter chain
*/
PROXY_DECLARE(void) ap_proxy_backend_broke(request_rec *r,
apr_bucket_brigade *brigade);
/**
* Transform buckets from one bucket allocator to another one by creating a
* transient bucket for each data bucket and let it use the data read from
* the old bucket. Metabuckets are transformed by just recreating them.
* Attention: Currently only the following bucket types are handled:
*
* All data buckets
* FLUSH
* EOS
*
* If an other bucket type is found its type is logged as a debug message
* and APR_EGENERAL is returned.
* @param r current request record of client request. Only used for logging
* purposes
* @param from the brigade that contains the buckets to transform
* @param to the brigade that will receive the transformed buckets
* @return APR_SUCCESS if all buckets could be transformed APR_EGENERAL
* otherwise
*/
PROXY_DECLARE(apr_status_t)
ap_proxy_buckets_lifetime_transform(request_rec *r, apr_bucket_brigade *from,
apr_bucket_brigade *to);
/**
* Return a hash based on the passed string
* @param str string to produce hash from
* @param method hashing method to use
* @return hash as unsigned int
*/
typedef enum { PROXY_HASHFUNC_DEFAULT, PROXY_HASHFUNC_APR, PROXY_HASHFUNC_FNV } proxy_hash_t;
PROXY_DECLARE(unsigned int)
ap_proxy_hashfunc(const char *str, proxy_hash_t method);
#define PROXY_LBMETHOD "proxylbmethod"
/* The number of dynamic workers that can be added when reconfiguring.
* If this limit is reached you must stop and restart the server.
*/
#define PROXY_DYNAMIC_BALANCER_LIMIT 16
/**
* Calculate number of maximum number of workers in scoreboard.
* @return number of workers to allocate in the scoreboard
*/
int ap_proxy_lb_workers(void);
/* For proxy_util */
extern module PROXY_DECLARE_DATA proxy_module;
extern int PROXY_DECLARE_DATA proxy_lb_workers;
#endif /*MOD_PROXY_H*/
/** @} */