include/haproxy/session.h - haproxy - Gitiles

 /*
  * include/haproxy/session.h
  * This file contains functions used to manage sessions.
  *
  * Copyright (C) 2000-2020 Willy Tarreau - w@1wt.eu
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation, version 2.1
  * exclusively.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */

 #ifndef _HAPROXY_SESSION_H
 #define _HAPROXY_SESSION_H

 #include <haproxy/api.h>
 #include <haproxy/global-t.h>
 #include <haproxy/obj_type-t.h>
 #include <haproxy/pool.h>
 #include <haproxy/server.h>
 #include <haproxy/session-t.h>
 #include <haproxy/stick_table.h>

 extern struct pool_head *pool_head_session;
 extern struct pool_head *pool_head_sess_srv_list;

 struct session *session_new(struct proxy *fe, struct listener *li, enum obj_type *origin);
 void session_free(struct session *sess);
 int session_accept_fd(struct connection *cli_conn);
 int conn_complete_session(struct connection *conn);
 struct task *session_expire_embryonic(struct task *t, void *context, unsigned int state);

 /* Remove the refcount from the session to the tracked counters, and clear the
  * pointer to ensure this is only performed once. The caller is responsible for
  * ensuring that the pointer is valid first.
  */
 static inline void session_store_counters(struct session *sess)
 {
 	void *ptr;
 	int i;
 	struct stksess *ts;

 	for (i = 0; i < MAX_SESS_STKCTR; i++) {
 		struct stkctr *stkctr = &sess->stkctr[i];

 		ts = stkctr_entry(stkctr);
 		if (!ts)
 			continue;

 		ptr = stktable_data_ptr(stkctr->table, ts, STKTABLE_DT_CONN_CUR);
 		if (ptr) {
 			HA_RWLOCK_WRLOCK(STK_SESS_LOCK, &ts->lock);

 			if (stktable_data_cast(ptr, conn_cur) > 0)
 				stktable_data_cast(ptr, conn_cur)--;

 			HA_RWLOCK_WRUNLOCK(STK_SESS_LOCK, &ts->lock);

 			/* If data was modified, we need to touch to re-schedule sync */
 			stktable_touch_local(stkctr->table, ts, 0);
 		}

 		stkctr_set_entry(stkctr, NULL);
 		stksess_kill_if_expired(stkctr->table, ts, 1);
 	}
 }

 /* Increase the number of cumulated HTTP requests in the tracked counters */
 static inline void session_inc_http_req_ctr(struct session *sess)
 {
 	int i;

 	for (i = 0; i < MAX_SESS_STKCTR; i++)
 		stkctr_inc_http_req_ctr(&sess->stkctr[i]);
 }

 /* Increase the number of cumulated failed HTTP requests in the tracked
  * counters. Only 4xx requests should be counted here so that we can
  * distinguish between errors caused by client behaviour and other ones.
  * Note that even 404 are interesting because they're generally caused by
  * vulnerability scans.
  */
 static inline void session_inc_http_err_ctr(struct session *sess)
 {
 	int i;

 	for (i = 0; i < MAX_SESS_STKCTR; i++)
 		stkctr_inc_http_err_ctr(&sess->stkctr[i]);
 }

 /* Increase the number of cumulated failed HTTP responses in the tracked
  * counters. Only some 5xx responses should be counted here so that we can
  * distinguish between server failures and errors triggered by the client
  * (i.e. 501 and 505 may be triggered and must be ignored).
  */
 static inline void session_inc_http_fail_ctr(struct session *sess)
 {
 	int i;

 	for (i = 0; i < MAX_SESS_STKCTR; i++)
 		stkctr_inc_http_fail_ctr(&sess->stkctr[i]);
 }


 /* Remove the connection from the session list, and destroy the srv_list if it's now empty */
 static inline void session_unown_conn(struct session *sess, struct connection *conn)
 {
 	struct sess_srv_list *srv_list = NULL;

 	BUG_ON(objt_listener(conn->target));

 	/* WT: this currently is a workaround for an inconsistency between
 	 * the link status of the connection in the session list and the
 	 * connection's owner. This should be removed as soon as all this
 	 * is addressed. Right now it's possible to enter here with a non-null
 	 * conn->owner that points to a dead session, but in this case the
 	 * element is not linked.
 	 */
 	if (!LIST_INLIST(&conn->session_list))
 		return;

 	if (conn->flags & CO_FL_SESS_IDLE)
 		sess->idle_conns--;
 	LIST_DEL_INIT(&conn->session_list);
 	conn->owner = NULL;
 	list_for_each_entry(srv_list, &sess->srv_list, srv_list) {
 		if (srv_list->target == conn->target) {
 			if (LIST_ISEMPTY(&srv_list->conn_list)) {
 				LIST_DELETE(&srv_list->srv_list);
 				pool_free(pool_head_sess_srv_list, srv_list);
 			}
 			break;
 		}
 	}
 }

 /* Add the connection <conn> to the server list of the session <sess>. This
  * function is called only if the connection is private. Nothing is performed if
  * the connection is already in the session sever list or if the session does
  * not own the connection.
  */
 static inline int session_add_conn(struct session *sess, struct connection *conn, void *target)
 {
 	struct sess_srv_list *srv_list = NULL;
 	int found = 0;

 	BUG_ON(objt_listener(conn->target));

 	/* Already attach to the session or not the connection owner */
 	if (!LIST_ISEMPTY(&conn->session_list) || (conn->owner && conn->owner != sess))
 		return 1;

 	list_for_each_entry(srv_list, &sess->srv_list, srv_list) {
 		if (srv_list->target == target) {
 			found = 1;
 			break;
 		}
 	}
 	if (!found) {
 		/* The session has no connection for the server, create a new entry */
 		srv_list = pool_alloc(pool_head_sess_srv_list);
 		if (!srv_list)
 			return 0;
 		srv_list->target = target;
 		LIST_INIT(&srv_list->conn_list);
 		LIST_APPEND(&sess->srv_list, &srv_list->srv_list);
 	}
 	LIST_APPEND(&srv_list->conn_list, &conn->session_list);
 	return 1;
 }

 /* Returns 0 if the session can keep the idle conn, -1 if it was destroyed. The
  * connection must be private.
  */
 static inline int session_check_idle_conn(struct session *sess, struct connection *conn)
 {
 	/* Another session owns this connection */
 	if (conn->owner != sess)
 		return 0;

 	if (sess->idle_conns >= sess->fe->max_out_conns) {
 		session_unown_conn(sess, conn);
 		conn->owner = NULL;
 		conn->flags &= ~CO_FL_SESS_IDLE;
 		conn->mux->destroy(conn->ctx);
 		return -1;
 	} else {
 		conn->flags |= CO_FL_SESS_IDLE;
 		sess->idle_conns++;
 	}
 	return 0;
 }

 /* Look for an available connection matching the target <target> in the server
  * list of the session <sess>. It returns a connection if found. Otherwise it
  * returns NULL.
  */
 static inline struct connection *session_get_conn(struct session *sess, void *target, int64_t hash)
 {
 	struct connection *srv_conn = NULL;
 	struct sess_srv_list *srv_list;

 	list_for_each_entry(srv_list, &sess->srv_list, srv_list) {
 		if (srv_list->target == target) {
 			list_for_each_entry(srv_conn, &srv_list->conn_list, session_list) {
 				if ((srv_conn->hash_node && srv_conn->hash_node->hash == hash) &&
 				    srv_conn->mux &&
 				    (srv_conn->mux->avail_streams(srv_conn) > 0) &&
 				    !(srv_conn->flags & CO_FL_WAIT_XPRT)) {
 					if (srv_conn->flags & CO_FL_SESS_IDLE) {
 						srv_conn->flags &= ~CO_FL_SESS_IDLE;
 						sess->idle_conns--;
 					}
 					goto end;
 				}
 			}
 			srv_conn = NULL; /* No available connection found */
 			goto end;
 		}
 	}

   end:
 	return srv_conn;
 }

 #endif /* _HAPROXY_SESSION_H */

 /*
  * Local variables:
  *  c-indent-level: 8
  *  c-basic-offset: 8
  * End:
  */
	/*
	* include/haproxy/session.h
	* This file contains functions used to manage sessions.
	*
	* Copyright (C) 2000-2020 Willy Tarreau - w@1wt.eu
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation, version 2.1
	* exclusively.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with this library; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#ifndef _HAPROXY_SESSION_H
	#define _HAPROXY_SESSION_H

	#include <haproxy/api.h>
	#include <haproxy/global-t.h>
	#include <haproxy/obj_type-t.h>
	#include <haproxy/pool.h>
	#include <haproxy/server.h>
	#include <haproxy/session-t.h>
	#include <haproxy/stick_table.h>

	extern struct pool_head *pool_head_session;
	extern struct pool_head *pool_head_sess_srv_list;

	struct session session_new(struct proxy fe, struct listener li, enum obj_type origin);
	void session_free(struct session *sess);
	int session_accept_fd(struct connection *cli_conn);
	int conn_complete_session(struct connection *conn);
	struct task session_expire_embryonic(struct task t, void *context, unsigned int state);

	/* Remove the refcount from the session to the tracked counters, and clear the
	* pointer to ensure this is only performed once. The caller is responsible for
	* ensuring that the pointer is valid first.
	*/
	static inline void session_store_counters(struct session *sess)
	{
	void *ptr;
	int i;
	struct stksess *ts;

	for (i = 0; i < MAX_SESS_STKCTR; i++) {
	struct stkctr *stkctr = &sess->stkctr[i];

	ts = stkctr_entry(stkctr);
	if (!ts)
	continue;

	ptr = stktable_data_ptr(stkctr->table, ts, STKTABLE_DT_CONN_CUR);
	if (ptr) {
	HA_RWLOCK_WRLOCK(STK_SESS_LOCK, &ts->lock);

	if (stktable_data_cast(ptr, conn_cur) > 0)
	stktable_data_cast(ptr, conn_cur)--;

	HA_RWLOCK_WRUNLOCK(STK_SESS_LOCK, &ts->lock);

	/* If data was modified, we need to touch to re-schedule sync */
	stktable_touch_local(stkctr->table, ts, 0);
	}

	stkctr_set_entry(stkctr, NULL);
	stksess_kill_if_expired(stkctr->table, ts, 1);
	}
	}

	/* Increase the number of cumulated HTTP requests in the tracked counters */
	static inline void session_inc_http_req_ctr(struct session *sess)
	{
	int i;

	for (i = 0; i < MAX_SESS_STKCTR; i++)
	stkctr_inc_http_req_ctr(&sess->stkctr[i]);
	}

	/* Increase the number of cumulated failed HTTP requests in the tracked
	* counters. Only 4xx requests should be counted here so that we can
	* distinguish between errors caused by client behaviour and other ones.
	* Note that even 404 are interesting because they're generally caused by
	* vulnerability scans.
	*/
	static inline void session_inc_http_err_ctr(struct session *sess)
	{
	int i;

	for (i = 0; i < MAX_SESS_STKCTR; i++)
	stkctr_inc_http_err_ctr(&sess->stkctr[i]);
	}

	/* Increase the number of cumulated failed HTTP responses in the tracked
	* counters. Only some 5xx responses should be counted here so that we can
	* distinguish between server failures and errors triggered by the client
	* (i.e. 501 and 505 may be triggered and must be ignored).
	*/
	static inline void session_inc_http_fail_ctr(struct session *sess)
	{
	int i;

	for (i = 0; i < MAX_SESS_STKCTR; i++)
	stkctr_inc_http_fail_ctr(&sess->stkctr[i]);
	}


	/* Remove the connection from the session list, and destroy the srv_list if it's now empty */
	static inline void session_unown_conn(struct session sess, struct connection conn)
	{
	struct sess_srv_list *srv_list = NULL;

	BUG_ON(objt_listener(conn->target));

	/* WT: this currently is a workaround for an inconsistency between
	* the link status of the connection in the session list and the
	* connection's owner. This should be removed as soon as all this
	* is addressed. Right now it's possible to enter here with a non-null
	* conn->owner that points to a dead session, but in this case the
	* element is not linked.
	*/
	if (!LIST_INLIST(&conn->session_list))
	return;

	if (conn->flags & CO_FL_SESS_IDLE)
	sess->idle_conns--;
	LIST_DEL_INIT(&conn->session_list);
	conn->owner = NULL;
	list_for_each_entry(srv_list, &sess->srv_list, srv_list) {
	if (srv_list->target == conn->target) {
	if (LIST_ISEMPTY(&srv_list->conn_list)) {
	LIST_DELETE(&srv_list->srv_list);
	pool_free(pool_head_sess_srv_list, srv_list);
	}
	break;
	}
	}
	}

	/* Add the connection <conn> to the server list of the session <sess>. This
	* function is called only if the connection is private. Nothing is performed if
	* the connection is already in the session sever list or if the session does
	* not own the connection.
	*/
	static inline int session_add_conn(struct session sess, struct connection conn, void *target)
	{
	struct sess_srv_list *srv_list = NULL;
	int found = 0;

	BUG_ON(objt_listener(conn->target));

	/* Already attach to the session or not the connection owner */
	if (!LIST_ISEMPTY(&conn->session_list) \|\| (conn->owner && conn->owner != sess))
	return 1;

	list_for_each_entry(srv_list, &sess->srv_list, srv_list) {
	if (srv_list->target == target) {
	found = 1;
	break;
	}
	}
	if (!found) {
	/* The session has no connection for the server, create a new entry */
	srv_list = pool_alloc(pool_head_sess_srv_list);
	if (!srv_list)
	return 0;
	srv_list->target = target;
	LIST_INIT(&srv_list->conn_list);
	LIST_APPEND(&sess->srv_list, &srv_list->srv_list);
	}
	LIST_APPEND(&srv_list->conn_list, &conn->session_list);
	return 1;
	}

	/* Returns 0 if the session can keep the idle conn, -1 if it was destroyed. The
	* connection must be private.
	*/
	static inline int session_check_idle_conn(struct session sess, struct connection conn)
	{
	/* Another session owns this connection */
	if (conn->owner != sess)
	return 0;

	if (sess->idle_conns >= sess->fe->max_out_conns) {
	session_unown_conn(sess, conn);
	conn->owner = NULL;
	conn->flags &= ~CO_FL_SESS_IDLE;
	conn->mux->destroy(conn->ctx);
	return -1;
	} else {
	conn->flags \|= CO_FL_SESS_IDLE;
	sess->idle_conns++;
	}
	return 0;
	}

	/* Look for an available connection matching the target <target> in the server
	* list of the session <sess>. It returns a connection if found. Otherwise it
	* returns NULL.
	*/
	static inline struct connection session_get_conn(struct session sess, void *target, int64_t hash)
	{
	struct connection *srv_conn = NULL;
	struct sess_srv_list *srv_list;

	list_for_each_entry(srv_list, &sess->srv_list, srv_list) {
	if (srv_list->target == target) {
	list_for_each_entry(srv_conn, &srv_list->conn_list, session_list) {
	if ((srv_conn->hash_node && srv_conn->hash_node->hash == hash) &&
	srv_conn->mux &&
	(srv_conn->mux->avail_streams(srv_conn) > 0) &&
	!(srv_conn->flags & CO_FL_WAIT_XPRT)) {
	if (srv_conn->flags & CO_FL_SESS_IDLE) {
	srv_conn->flags &= ~CO_FL_SESS_IDLE;
	sess->idle_conns--;
	}
	goto end;
	}
	}
	srv_conn = NULL; /* No available connection found */
	goto end;
	}
	}

	end:
	return srv_conn;
	}

	#endif /* _HAPROXY_SESSION_H */

	/*
	* Local variables:
	* c-indent-level: 8
	* c-basic-offset: 8
	* End:
	*/