diff options
Diffstat (limited to 'src/session.c')
| -rw-r--r-- | src/session.c | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/src/session.c b/src/session.c new file mode 100644 index 0000000..66120d7 --- /dev/null +++ b/src/session.c @@ -0,0 +1,460 @@ +/* + * Session management functions. + * + * Copyright 2000-2015 Willy Tarreau <w@1wt.eu> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +#include <haproxy/api.h> +#include <haproxy/connection.h> +#include <haproxy/global.h> +#include <haproxy/http.h> +#include <haproxy/listener.h> +#include <haproxy/log.h> +#include <haproxy/pool.h> +#include <haproxy/proxy.h> +#include <haproxy/session.h> +#include <haproxy/tcp_rules.h> +#include <haproxy/tools.h> +#include <haproxy/vars.h> + + +DECLARE_POOL(pool_head_session, "session", sizeof(struct session)); +DECLARE_POOL(pool_head_sess_srv_list, "session server list", + sizeof(struct sess_srv_list)); + +int conn_complete_session(struct connection *conn); + +/* Create a a new session and assign it to frontend <fe>, listener <li>, + * origin <origin>, set the current date and clear the stick counters pointers. + * Returns the session upon success or NULL. The session may be released using + * session_free(). Note: <li> may be NULL. + */ +struct session *session_new(struct proxy *fe, struct listener *li, enum obj_type *origin) +{ + struct session *sess; + + sess = pool_alloc(pool_head_session); + if (sess) { + sess->listener = li; + sess->fe = fe; + sess->origin = origin; + sess->accept_date = date; /* user-visible date for logging */ + sess->tv_accept = now; /* corrected date for internal use */ + memset(sess->stkctr, 0, sizeof(sess->stkctr)); + vars_init_head(&sess->vars, SCOPE_SESS); + sess->task = NULL; + sess->t_handshake = -1; /* handshake not done yet */ + sess->t_idle = -1; + _HA_ATOMIC_INC(&totalconn); + _HA_ATOMIC_INC(&jobs); + LIST_INIT(&sess->srv_list); + sess->idle_conns = 0; + sess->flags = SESS_FL_NONE; + sess->src = NULL; + sess->dst = NULL; + } + return sess; +} + +void session_free(struct session *sess) +{ + struct connection *conn, *conn_back; + struct sess_srv_list *srv_list, *srv_list_back; + + if (sess->listener) + listener_release(sess->listener); + session_store_counters(sess); + vars_prune_per_sess(&sess->vars); + conn = objt_conn(sess->origin); + if (conn != NULL && conn->mux) + conn->mux->destroy(conn->ctx); + list_for_each_entry_safe(srv_list, srv_list_back, &sess->srv_list, srv_list) { + list_for_each_entry_safe(conn, conn_back, &srv_list->conn_list, session_list) { + LIST_DEL_INIT(&conn->session_list); + if (conn->mux) { + conn->owner = NULL; + conn->flags &= ~CO_FL_SESS_IDLE; + conn->mux->destroy(conn->ctx); + } else { + /* We have a connection, but not yet an associated mux. + * So destroy it now. + */ + conn_stop_tracking(conn); + conn_full_close(conn); + conn_free(conn); + } + } + pool_free(pool_head_sess_srv_list, srv_list); + } + sockaddr_free(&sess->src); + sockaddr_free(&sess->dst); + pool_free(pool_head_session, sess); + _HA_ATOMIC_DEC(&jobs); +} + +/* callback used from the connection/mux layer to notify that a connection is + * going to be released. + */ +void conn_session_free(struct connection *conn) +{ + session_free(conn->owner); + conn->owner = NULL; +} + +/* count a new session to keep frontend, listener and track stats up to date */ +static void session_count_new(struct session *sess) +{ + struct stkctr *stkctr; + void *ptr; + int i; + + proxy_inc_fe_sess_ctr(sess->listener, sess->fe); + + for (i = 0; i < MAX_SESS_STKCTR; i++) { + stkctr = &sess->stkctr[i]; + if (!stkctr_entry(stkctr)) + continue; + + ptr = stktable_data_ptr(stkctr->table, stkctr_entry(stkctr), STKTABLE_DT_SESS_CNT); + if (ptr) + HA_ATOMIC_INC(&stktable_data_cast(ptr, std_t_uint)); + + ptr = stktable_data_ptr(stkctr->table, stkctr_entry(stkctr), STKTABLE_DT_SESS_RATE); + if (ptr) + update_freq_ctr_period(&stktable_data_cast(ptr, std_t_frqp), + stkctr->table->data_arg[STKTABLE_DT_SESS_RATE].u, 1); + } +} + +/* This function is called from the protocol layer accept() in order to + * instantiate a new session on behalf of a given listener and frontend. It + * returns a positive value upon success, 0 if the connection can be ignored, + * or a negative value upon critical failure. The accepted connection is + * closed if we return <= 0. If no handshake is needed, it immediately tries + * to instantiate a new stream. The connection must already have been filled + * with the incoming connection handle (a fd), a target (the listener) and a + * source address. + */ +int session_accept_fd(struct connection *cli_conn) +{ + struct listener *l = __objt_listener(cli_conn->target); + struct proxy *p = l->bind_conf->frontend; + int cfd = cli_conn->handle.fd; + struct session *sess; + int ret; + + ret = -1; /* assume unrecoverable error by default */ + + cli_conn->proxy_netns = l->rx.settings->netns; + + if (conn_prepare(cli_conn, l->rx.proto, l->bind_conf->xprt) < 0) + goto out_free_conn; + + conn_ctrl_init(cli_conn); + + /* wait for a PROXY protocol header */ + if (l->options & LI_O_ACC_PROXY) + cli_conn->flags |= CO_FL_ACCEPT_PROXY; + + /* wait for a NetScaler client IP insertion protocol header */ + if (l->options & LI_O_ACC_CIP) + cli_conn->flags |= CO_FL_ACCEPT_CIP; + + /* Add the handshake pseudo-XPRT */ + if (cli_conn->flags & (CO_FL_ACCEPT_PROXY | CO_FL_ACCEPT_CIP)) { + if (xprt_add_hs(cli_conn) != 0) + goto out_free_conn; + } + sess = session_new(p, l, &cli_conn->obj_type); + if (!sess) + goto out_free_conn; + + conn_set_owner(cli_conn, sess, NULL); + + /* now evaluate the tcp-request layer4 rules. We only need a session + * and no stream for these rules. + */ + if ((l->options & LI_O_TCP_L4_RULES) && !tcp_exec_l4_rules(sess)) { + /* let's do a no-linger now to close with a single RST. */ + if (!(cli_conn->flags & CO_FL_FDLESS)) + setsockopt(cfd, SOL_SOCKET, SO_LINGER, (struct linger *) &nolinger, sizeof(struct linger)); + ret = 0; /* successful termination */ + goto out_free_sess; + } + /* TCP rules may flag the connection as needing proxy protocol, now that it's done we can start ourxprt */ + if (conn_xprt_start(cli_conn) < 0) + goto out_free_sess; + + /* FIXME/WTA: we should implement the setsockopt() calls at the proto + * level instead and let non-inet protocols implement their own equivalent. + */ + if (cli_conn->flags & CO_FL_FDLESS) + goto skip_fd_setup; + + /* Adjust some socket options */ + if (l->rx.addr.ss_family == AF_INET || l->rx.addr.ss_family == AF_INET6) { + setsockopt(cfd, IPPROTO_TCP, TCP_NODELAY, (char *) &one, sizeof(one)); + + if (p->options & PR_O_TCP_CLI_KA) { + setsockopt(cfd, SOL_SOCKET, SO_KEEPALIVE, (char *) &one, sizeof(one)); + +#ifdef TCP_KEEPCNT + if (p->clitcpka_cnt) + setsockopt(cfd, IPPROTO_TCP, TCP_KEEPCNT, &p->clitcpka_cnt, sizeof(p->clitcpka_cnt)); +#endif + +#ifdef TCP_KEEPIDLE + if (p->clitcpka_idle) + setsockopt(cfd, IPPROTO_TCP, TCP_KEEPIDLE, &p->clitcpka_idle, sizeof(p->clitcpka_idle)); +#endif + +#ifdef TCP_KEEPINTVL + if (p->clitcpka_intvl) + setsockopt(cfd, IPPROTO_TCP, TCP_KEEPINTVL, &p->clitcpka_intvl, sizeof(p->clitcpka_intvl)); +#endif + } + + if (p->options & PR_O_TCP_NOLING) + HA_ATOMIC_OR(&fdtab[cfd].state, FD_LINGER_RISK); + +#if defined(TCP_MAXSEG) + if (l->maxseg < 0) { + /* we just want to reduce the current MSS by that value */ + int mss; + socklen_t mss_len = sizeof(mss); + if (getsockopt(cfd, IPPROTO_TCP, TCP_MAXSEG, &mss, &mss_len) == 0) { + mss += l->maxseg; /* remember, it's < 0 */ + setsockopt(cfd, IPPROTO_TCP, TCP_MAXSEG, &mss, sizeof(mss)); + } + } +#endif + } + + if (global.tune.client_sndbuf) + setsockopt(cfd, SOL_SOCKET, SO_SNDBUF, &global.tune.client_sndbuf, sizeof(global.tune.client_sndbuf)); + + if (global.tune.client_rcvbuf) + setsockopt(cfd, SOL_SOCKET, SO_RCVBUF, &global.tune.client_rcvbuf, sizeof(global.tune.client_rcvbuf)); + + skip_fd_setup: + /* OK, now either we have a pending handshake to execute with and then + * we must return to the I/O layer, or we can proceed with the end of + * the stream initialization. In case of handshake, we also set the I/O + * timeout to the frontend's client timeout and register a task in the + * session for this purpose. The connection's owner is left to the + * session during this period. + * + * At this point we set the relation between sess/task/conn this way : + * + * +----------------- task + * | | + * orig -- sess <-- context | + * | ^ | | + * v | | | + * conn -- owner ---> task <-----+ + */ + if (cli_conn->flags & (CO_FL_WAIT_XPRT | CO_FL_EARLY_SSL_HS)) { + if (unlikely((sess->task = task_new_here()) == NULL)) + goto out_free_sess; + + sess->task->context = sess; + sess->task->nice = l->nice; + sess->task->process = session_expire_embryonic; + sess->task->expire = tick_add_ifset(now_ms, p->timeout.client); + task_queue(sess->task); + return 1; + } + + /* OK let's complete stream initialization since there is no handshake */ + if (conn_complete_session(cli_conn) >= 0) + return 1; + + /* if we reach here we have deliberately decided not to keep this + * session (e.g. tcp-request rule), so that's not an error we should + * try to protect against. + */ + ret = 0; + + /* error unrolling */ + out_free_sess: + /* prevent call to listener_release during session_free. It will be + * done below, for all errors. */ + sess->listener = NULL; + session_free(sess); + + out_free_conn: + if (ret < 0 && l->bind_conf->xprt == xprt_get(XPRT_RAW) && + p->mode == PR_MODE_HTTP && l->bind_conf->mux_proto == NULL && + !(cli_conn->flags & CO_FL_FDLESS)) { + /* critical error, no more memory, try to emit a 500 response */ + send(cfd, http_err_msgs[HTTP_ERR_500], strlen(http_err_msgs[HTTP_ERR_500]), + MSG_DONTWAIT|MSG_NOSIGNAL); + } + + conn_stop_tracking(cli_conn); + conn_full_close(cli_conn); + conn_free(cli_conn); + listener_release(l); + return ret; +} + + +/* prepare the trash with a log prefix for session <sess>. It only works with + * embryonic sessions based on a real connection. This function requires that + * at sess->origin points to the incoming connection. + */ +static void session_prepare_log_prefix(struct session *sess) +{ + const struct sockaddr_storage *src; + struct tm tm; + char pn[INET6_ADDRSTRLEN]; + int ret; + char *end; + + src = sess_src(sess); + ret = (src ? addr_to_str(src, pn, sizeof(pn)) : 0); + if (ret <= 0) + chunk_printf(&trash, "unknown ["); + else if (ret == AF_UNIX) + chunk_printf(&trash, "%s:%d [", pn, sess->listener->luid); + else + chunk_printf(&trash, "%s:%d [", pn, get_host_port(src)); + + get_localtime(sess->accept_date.tv_sec, &tm); + end = date2str_log(trash.area + trash.data, &tm, &(sess->accept_date), + trash.size - trash.data); + trash.data = end - trash.area; + if (sess->listener->name) + chunk_appendf(&trash, "] %s/%s", sess->fe->id, sess->listener->name); + else + chunk_appendf(&trash, "] %s/%d", sess->fe->id, sess->listener->luid); +} + +/* This function kills an existing embryonic session. It stops the connection's + * transport layer, releases assigned resources, resumes the listener if it was + * disabled and finally kills the file descriptor. This function requires that + * sess->origin points to the incoming connection. + */ +static void session_kill_embryonic(struct session *sess, unsigned int state) +{ + int level = LOG_INFO; + struct connection *conn = __objt_conn(sess->origin); + struct task *task = sess->task; + unsigned int log = sess->fe->to_log; + const char *err_msg; + + if (sess->fe->options2 & PR_O2_LOGERRORS) + level = LOG_ERR; + + if (log && (sess->fe->options & PR_O_NULLNOLOG)) { + /* with "option dontlognull", we don't log connections with no transfer */ + if (!conn->err_code || + conn->err_code == CO_ER_PRX_EMPTY || conn->err_code == CO_ER_PRX_ABORT || + conn->err_code == CO_ER_CIP_EMPTY || conn->err_code == CO_ER_CIP_ABORT || + conn->err_code == CO_ER_SSL_EMPTY || conn->err_code == CO_ER_SSL_ABORT) + log = 0; + } + + if (log) { + if (!conn->err_code && (state & TASK_WOKEN_TIMER)) { + if (conn->flags & CO_FL_ACCEPT_PROXY) + conn->err_code = CO_ER_PRX_TIMEOUT; + else if (conn->flags & CO_FL_ACCEPT_CIP) + conn->err_code = CO_ER_CIP_TIMEOUT; + else if (conn->flags & CO_FL_SSL_WAIT_HS) + conn->err_code = CO_ER_SSL_TIMEOUT; + } + + if(!LIST_ISEMPTY(&sess->fe->logformat_error)) { + /* Display a log line following the configured error-log-format. */ + sess_log(sess); + } + else { + session_prepare_log_prefix(sess); + err_msg = conn_err_code_str(conn); + if (err_msg) + send_log(sess->fe, level, "%s: %s\n", trash.area, + err_msg); + else + send_log(sess->fe, level, "%s: unknown connection error (code=%d flags=%08x)\n", + trash.area, conn->err_code, conn->flags); + } + } + + /* kill the connection now */ + conn_stop_tracking(conn); + conn_full_close(conn); + conn_free(conn); + sess->origin = NULL; + + task_destroy(task); + session_free(sess); +} + +/* Manages the embryonic session timeout. It is only called when the timeout + * strikes and performs the required cleanup. It's only exported to make it + * resolve in "show tasks". + */ +struct task *session_expire_embryonic(struct task *t, void *context, unsigned int state) +{ + struct session *sess = context; + + if (!(state & TASK_WOKEN_TIMER)) + return t; + + session_kill_embryonic(sess, state); + return NULL; +} + +/* Finish initializing a session from a connection, or kills it if the + * connection shows and error. Returns <0 if the connection was killed. It may + * be called either asynchronously when ssl handshake is done with an embryonic + * session, or synchronously to finalize the session. The distinction is made + * on sess->task which is only set in the embryonic session case. + */ +int conn_complete_session(struct connection *conn) +{ + struct session *sess = conn->owner; + + sess->t_handshake = tv_ms_elapsed(&sess->tv_accept, &now); + + if (conn->flags & CO_FL_ERROR) + goto fail; + + /* if logs require transport layer information, note it on the connection */ + if (sess->fe->to_log & LW_XPRT) + conn->flags |= CO_FL_XPRT_TRACKED; + + /* we may have some tcp-request-session rules */ + if ((sess->listener->options & LI_O_TCP_L5_RULES) && !tcp_exec_l5_rules(sess)) + goto fail; + + session_count_new(sess); + if (conn_install_mux_fe(conn, NULL) < 0) + goto fail; + + /* the embryonic session's task is not needed anymore */ + task_destroy(sess->task); + sess->task = NULL; + conn_set_owner(conn, sess, conn_session_free); + + return 0; + + fail: + if (sess->task) + session_kill_embryonic(sess, 0); + return -1; +} + +/* + * Local variables: + * c-indent-level: 8 + * c-basic-offset: 8 + * End: + */ |