blob: 06d3000e4203019ac71373331233d7f4b2e07213 [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 <common/config.h>
#include <common/buffer.h>
#include <common/debug.h>
#include <common/memory.h>
#include <types/global.h>
#include <types/session.h>
#include <proto/connection.h>
#include <proto/listener.h>
#include <proto/log.h>
#include <proto/proto_http.h>
#include <proto/proxy.h>
#include <proto/session.h>
#include <proto/stream.h>
#include <proto/tcp_rules.h>
#include <proto/vars.h>
struct pool_head *pool2_session;
static int conn_complete_session(struct connection *conn);
static int conn_update_session(struct connection *conn);
static struct task *session_expire_embryonic(struct task *t);
/* data layer callbacks for an embryonic stream */
struct data_cb sess_conn_cb = {
.recv = NULL,
.send = NULL,
.wake = conn_update_session,
.init = conn_complete_session,
.name = "SESS",
};
/* 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().
*/
struct session *session_new(struct proxy *fe, struct listener *li, enum obj_type *origin)
{
struct session *sess;
sess = pool_alloc2(pool2_session);
if (sess) {
sess->listener = li;
sess->fe = fe;
LIST_INIT(&sess->streams);
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);
}
return sess;
}
void session_free(struct session *sess)
{
if (!LIST_ISEMPTY(&sess->streams))
return;
session_store_counters(sess);
vars_prune_per_sess(&sess->vars);
pool_free2(pool2_session, sess);
}
/* perform minimal intializations, report 0 in case of error, 1 if OK. */
int init_session()
{
pool2_session = create_pool("session", sizeof(struct session), MEM_F_SHARED);
return pool2_session != 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)
stktable_data_cast(ptr, sess_cnt)++;
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
* instanciate 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 file descriptor is
* closed if we return <= 0. If no handshake is needed, it immediately tries
* to instanciate a new stream.
*/
int session_accept_fd(struct listener *l, int cfd, struct sockaddr_storage *addr)
{
struct connection *cli_conn;
struct proxy *p = l->bind_conf->frontend;
struct session *sess;
struct task *t;
int ret;
ret = -1; /* assume unrecoverable error by default */
if (unlikely((cli_conn = conn_new()) == NULL))
goto out_close;
conn_prepare(cli_conn, l->proto, l->bind_conf->xprt);
cli_conn->t.sock.fd = cfd;
cli_conn->addr.from = *addr;
cli_conn->flags |= CO_FL_ADDR_FROM_SET;
cli_conn->target = &l->obj_type;
cli_conn->proxy_netns = l->netns;
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;
conn_sock_want_recv(cli_conn);
}
/* wait for a NetScaler client IP insertion protocol header */
if (l->options & LI_O_ACC_CIP) {
cli_conn->flags |= CO_FL_ACCEPT_CIP;
conn_sock_want_recv(cli_conn);
}
conn_data_want_recv(cli_conn);
if (conn_xprt_init(cli_conn) < 0)
goto out_free_conn;
sess = session_new(p, l, &cli_conn->obj_type);
if (!sess)
goto out_free_conn;
p->feconn++;
/* This session was accepted, count it now */
if (p->feconn > p->fe_counters.conn_max)
p->fe_counters.conn_max = p->feconn;
proxy_inc_fe_conn_ctr(l, p);
/* 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;
}
/* monitor-net and health mode are processed immediately after TCP
* connection rules. This way it's possible to block them, but they
* never use the lower data layers, they send directly over the socket,
* as they were designed for. We first flush the socket receive buffer
* in order to avoid emission of an RST by the system. We ignore any
* error.
*/
if (unlikely((p->mode == PR_MODE_HEALTH) ||
((l->options & LI_O_CHK_MONNET) &&
addr->ss_family == AF_INET &&
(((struct sockaddr_in *)addr)->sin_addr.s_addr & p->mon_mask.s_addr) == p->mon_net.s_addr))) {
/* we have 4 possibilities here :
* - HTTP mode, from monitoring address => send "HTTP/1.0 200 OK"
* - HEALTH mode with HTTP check => send "HTTP/1.0 200 OK"
* - HEALTH mode without HTTP check => just send "OK"
* - TCP mode from monitoring address => just close
*/
if (l->proto->drain)
l->proto->drain(cfd);
if (p->mode == PR_MODE_HTTP ||
(p->mode == PR_MODE_HEALTH && (p->options2 & PR_O2_CHK_ANY) == PR_O2_HTTP_CHK))
send(cfd, "HTTP/1.0 200 OK\r\n\r\n", 19, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_MORE);
else if (p->mode == PR_MODE_HEALTH)
send(cfd, "OK\n", 3, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_MORE);
ret = 0;
goto out_free_sess;
}
/* Adjust some socket options */
if (l->addr.ss_family == AF_INET || l->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));
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));
if (unlikely((t = task_new()) == NULL))
goto out_free_sess;
t->context = sess;
t->nice = l->nice;
/* 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.
*
* At this point we set the relation between sess/task/conn this way :
*
* orig -- sess <-- context
* | |
* v |
* conn -- owner ---> task
*/
if (cli_conn->flags & CO_FL_HANDSHAKE) {
conn_attach(cli_conn, t, &sess_conn_cb);
t->process = session_expire_embryonic;
t->expire = tick_add_ifset(now_ms, p->timeout.client);
task_queue(t);
cli_conn->flags |= CO_FL_INIT_DATA;
return 1;
}
/* OK let's complete stream initialization since there is no handshake */
cli_conn->flags |= CO_FL_CONNECTED;
/* if logs require transport layer information, note it on the connection */
if (sess->fe->to_log & LW_XPRT)
cli_conn->flags |= CO_FL_XPRT_TRACKED;
/* we may have some tcp-request-session rules */
if ((l->options & LI_O_TCP_L5_RULES) && !tcp_exec_l5_rules(sess))
goto out_free_sess;
session_count_new(sess);
if (!stream_new(sess, t, &cli_conn->obj_type))
goto out_free_task;
task_wakeup(t, TASK_WOKEN_INIT);
return 1;
out_free_task:
task_free(t);
out_free_sess:
p->feconn--;
session_free(sess);
out_free_conn:
cli_conn->flags &= ~CO_FL_XPRT_TRACKED;
conn_xprt_close(cli_conn);
conn_free(cli_conn);
out_close:
if (ret < 0 && l->bind_conf->xprt == xprt_get(XPRT_RAW) && p->mode == PR_MODE_HTTP) {
/* critical error, no more memory, try to emit a 500 response */
struct chunk *err_msg = &p->errmsg[HTTP_ERR_500];
if (!err_msg->str)
err_msg = &http_err_chunks[HTTP_ERR_500];
send(cfd, err_msg->str, err_msg->len, MSG_DONTWAIT|MSG_NOSIGNAL);
}
if (fdtab[cfd].owner)
fd_delete(cfd);
else
close(cfd);
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 = addr_to_str(&cli_conn->addr.from, pn, sizeof(pn));
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->addr.from));
get_localtime(sess->accept_date.tv_sec, &tm);
end = date2str_log(trash.str + trash.len, &tm, &(sess->accept_date), trash.size - trash.len);
trash.len = end - trash.str;
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, struct task *task)
{
int level = LOG_INFO;
struct connection *conn = __objt_conn(sess->origin);
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 && (task->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.str, err_msg);
else
send_log(sess->fe, level, "%s: unknown connection error (code=%d flags=%08x)\n",
trash.str, conn->err_code, conn->flags);
}
/* kill the connection now */
conn_force_close(conn);
conn_free(conn);
sess->fe->feconn--;
if (!(sess->listener->options & LI_O_UNLIMITED))
actconn--;
jobs--;
sess->listener->nbconn--;
if (sess->listener->state == LI_FULL)
resume_listener(sess->listener);
/* Dequeues all of the listeners waiting for a resource */
if (!LIST_ISEMPTY(&global_listener_queue))
dequeue_all_listeners(&global_listener_queue);
if (!LIST_ISEMPTY(&sess->fe->listener_queue) &&
(!sess->fe->fe_sps_lim || freq_ctr_remain(&sess->fe->fe_sess_per_sec, sess->fe->fe_sps_lim, 0) > 0))
dequeue_all_listeners(&sess->fe->listener_queue);
task_delete(task);
task_free(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)
{
struct session *sess = t->context;
if (!(t->state & TASK_WOKEN_TIMER))
return t;
session_kill_embryonic(sess, t);
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.
*/
static int conn_complete_session(struct connection *conn)
{
struct task *task = conn->owner;
struct session *sess = task->context;
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);
task->process = sess->listener->handler;
if (!stream_new(sess, task, &conn->obj_type))
goto fail;
conn->flags &= ~CO_FL_INIT_DATA;
task_wakeup(task, TASK_WOKEN_INIT);
return 0;
fail:
session_kill_embryonic(sess, task);
return -1;
}
/* Update a session status. The connection is killed in case of
* error, and <0 will be returned. Otherwise it does nothing.
*/
static int conn_update_session(struct connection *conn)
{
struct task *task = conn->owner;
struct session *sess = task->context;
if (conn->flags & CO_FL_ERROR) {
session_kill_embryonic(sess, task);
return -1;
}
return 0;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/