/*
* This function initiates a connection to the server assigned to this session
* (s->target, s->si[1].addr.to). It will assign a server if none
* is assigned yet.
* It can return one of :
* - SN_ERR_NONE if everything's OK
* - SN_ERR_SRVTO if there are no more servers
* - SN_ERR_SRVCL if the connection was refused by the server
* - SN_ERR_PRXCOND if the connection has been limited by the proxy (maxconn)
* - SN_ERR_RESOURCE if a system resource is lacking (eg: fd limits, ports, ...)
* - SN_ERR_INTERNAL for any other purely internal errors
* Additionnally, in the case of SN_ERR_RESOURCE, an emergency log will be emitted.
* The server-facing stream interface is expected to hold a pre-allocated connection
* in s->si[1].conn.
*/
int connect_server(struct session *s)
{
struct connection *cli_conn;
struct connection *srv_conn;
struct server *srv;
int reuse = 0;
int err;
srv_conn = objt_conn(s->si[1].end);
if (srv_conn)
reuse = s->target == srv_conn->target;
if (reuse) {
/* Disable connection reuse if a dynamic source is used.
* As long as we don't share connections between servers,
* we don't need to disable connection reuse on no-idempotent
* requests nor when PROXY protocol is used.
*/
srv = objt_server(s->target);
if (srv && srv->conn_src.opts & CO_SRC_BIND) {
if ((srv->conn_src.opts & CO_SRC_TPROXY_MASK) == CO_SRC_TPROXY_DYN)
reuse = 0;
}
else if (s->be->conn_src.opts & CO_SRC_BIND) {
if ((s->be->conn_src.opts & CO_SRC_TPROXY_MASK) == CO_SRC_TPROXY_DYN)
reuse = 0;
}
}
srv_conn = si_alloc_conn(&s->si[1], reuse);
if (!srv_conn)
return SN_ERR_RESOURCE;
if (!(s->flags & SN_ADDR_SET)) {
err = assign_server_address(s);
if (err != SRV_STATUS_OK)
return SN_ERR_INTERNAL;
}
if (!conn_xprt_ready(srv_conn)) {
/* the target was only on the session, assign it to the SI now */
srv_conn->target = s->target;
/* set the correct protocol on the output stream interface */
if (objt_server(s->target)) {
conn_prepare(srv_conn, protocol_by_family(srv_conn->addr.to.ss_family), objt_server(s->target)->xprt);
}
else if (obj_type(s->target) == OBJ_TYPE_PROXY) {
/* proxies exclusively run on raw_sock right now */
conn_prepare(srv_conn, protocol_by_family(srv_conn->addr.to.ss_family), &raw_sock);
if (!objt_conn(s->si[1].end) || !objt_conn(s->si[1].end)->ctrl)
return SN_ERR_INTERNAL;
}
else
return SN_ERR_INTERNAL; /* how did we get there ? */
/* process the case where the server requires the PROXY protocol to be sent */
srv_conn->send_proxy_ofs = 0;
if (objt_server(s->target) && objt_server(s->target)->pp_opts) {
srv_conn->send_proxy_ofs = 1; /* must compute size */
cli_conn = objt_conn(s->si[0].end);
if (cli_conn)
conn_get_to_addr(cli_conn);
}
si_attach_conn(&s->si[1], srv_conn);
assign_tproxy_address(s);
}
else {
/* the connection is being reused, just re-attach it */
si_attach_conn(&s->si[1], srv_conn);
s->flags |= SN_SRV_REUSED;
}
/* flag for logging source ip/port */
if (s->fe->options2 & PR_O2_SRC_ADDR)
s->si[1].flags |= SI_FL_SRC_ADDR;
/* disable lingering */
if (s->be->options & PR_O_TCP_NOLING)
s->si[1].flags |= SI_FL_NOLINGER;
err = si_connect(&s->si[1]);
if (err != SN_ERR_NONE)
return err;
/* set connect timeout */
s->si[1].exp = tick_add_ifset(now_ms, s->be->timeout.connect);
srv = objt_server(s->target);
if (srv) {
s->flags |= SN_CURR_SESS;
srv->cur_sess++;
if (srv->cur_sess > srv->counters.cur_sess_max)
srv->counters.cur_sess_max = srv->cur_sess;
if (s->be->lbprm.server_take_conn)
s->be->lbprm.server_take_conn(srv);
}
return SN_ERR_NONE; /* connection is OK */
}
/*
* Create a new peer session in assigned state (connect will start automatically)
*/
static struct stream *peer_session_create(struct peer *peer, struct peer_session *ps)
{
struct listener *l = LIST_NEXT(&peer->peers->peers_fe->conf.listeners, struct listener *, by_fe);
struct proxy *p = (struct proxy *)l->frontend; /* attached frontend */
struct appctx *appctx;
struct session *sess;
struct stream *s;
struct task *t;
struct connection *conn;
ps->reconnect = tick_add(now_ms, MS_TO_TICKS(5000));
ps->statuscode = PEER_SESS_SC_CONNECTCODE;
s = NULL;
appctx = appctx_new(&peer_applet);
if (!appctx)
goto out_close;
appctx->st0 = PEER_SESS_ST_CONNECT;
appctx->ctx.peers.ptr = (void *)ps;
sess = session_new(p, l, &appctx->obj_type);
if (!sess) {
Alert("out of memory in peer_session_create().\n");
goto out_free_appctx;
}
if ((t = task_new()) == NULL) {
Alert("out of memory in peer_session_create().\n");
goto out_free_sess;
}
t->nice = l->nice;
if ((s = stream_new(sess, t, &appctx->obj_type)) == NULL) {
Alert("Failed to initialize stream in peer_session_create().\n");
goto out_free_task;
}
/* The tasks below are normally what is supposed to be done by
* fe->accept().
*/
s->flags = SF_ASSIGNED|SF_ADDR_SET;
/* applet is waiting for data */
si_applet_cant_get(&s->si[0]);
appctx_wakeup(appctx);
/* initiate an outgoing connection */
si_set_state(&s->si[1], SI_ST_ASS);
/* automatically prepare the stream interface to connect to the
* pre-initialized connection in si->conn.
*/
if (unlikely((conn = conn_new()) == NULL))
goto out_free_strm;
conn_prepare(conn, peer->proto, peer->xprt);
si_attach_conn(&s->si[1], conn);
conn->target = s->target = &s->be->obj_type;
memcpy(&conn->addr.to, &peer->addr, sizeof(conn->addr.to));
s->do_log = NULL;
s->uniq_id = 0;
s->res.flags |= CF_READ_DONTWAIT;
l->nbconn++; /* warning! right now, it's up to the handler to decrease this */
p->feconn++;/* beconn will be increased later */
jobs++;
if (!(s->sess->listener->options & LI_O_UNLIMITED))
actconn++;
totalconn++;
ps->appctx = appctx;
ps->stream = s;
return s;
/* Error unrolling */
out_free_strm:
LIST_DEL(&s->list);
pool_free2(pool2_stream, s);
out_free_task:
task_free(t);
out_free_sess:
session_free(sess);
out_free_appctx:
appctx_free(appctx);
out_close:
return s;
}
