blob: 34167e7419828f385a985124232c7f1f7c5e6184 [file] [log] [blame]
/*
* 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/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);
static struct task *session_expire_embryonic(struct task *t, void *context, unsigned short state);
/* 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(&sess->vars, SCOPE_SESS);
sess->task = NULL;
sess->t_handshake = -1; /* handshake not done yet */
_HA_ATOMIC_ADD(&totalconn, 1);
_HA_ATOMIC_ADD(&jobs, 1);
LIST_INIT(&sess->srv_list);
sess->idle_conns = 0;
sess->flags = SESS_FL_NONE;
}
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);
}
pool_free(pool_head_session, sess);
_HA_ATOMIC_SUB(&jobs, 1);
}
/* 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_ADD(&stktable_data_cast(ptr, sess_cnt), 1);
ptr = stktable_data_ptr(stkctr->table, stkctr_entry(stkctr), STKTABLE_DT_SESS_RATE);
if (ptr)
update_freq_ctr_period(&stktable_data_cast(ptr, sess_rate),
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;
conn_prepare(cli_conn, l->rx.proto, l->bind_conf->xprt);
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;
if (conn_xprt_init(cli_conn) < 0)
goto out_free_conn;
/* 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. */
setsockopt(cfd, SOL_SOCKET, SO_LINGER, (struct linger *) &nolinger, sizeof(struct linger));
ret = 0; /* successful termination */
goto out_free_sess;
}
/* 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)
fdtab[cfd].linger_risk = 1;
#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));
/* 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(tid_bit)) == 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) {
/* 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)
{
struct tm tm;
char pn[INET6_ADDRSTRLEN];
int ret;
char *end;
struct connection *cli_conn = __objt_conn(sess->origin);
ret = conn_get_src(cli_conn) ? addr_to_str(cli_conn->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(cli_conn->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 short 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;
}
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.
*/
static struct task *session_expire_embryonic(struct task *t, void *context, unsigned short 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:
*/