blob: 3cc355a84bdb80552a3248655928fdfb1d881371 [file] [log] [blame]
/*
* Proxy variables and functions.
*
* Copyright 2000-2006 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 <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <common/defaults.h>
#include <common/compat.h>
#include <common/config.h>
#include <common/time.h>
#include <types/global.h>
#include <types/polling.h>
#include <proto/client.h>
#include <proto/fd.h>
#include <proto/log.h>
#include <proto/proxy.h>
int listeners; /* # of listeners */
struct proxy *proxy = NULL; /* list of all existing proxies */
/*
* This function returns a string containing the type of the proxy in a format
* suitable for error messages, from its capabilities.
*/
const char *proxy_type_str(struct proxy *proxy)
{
int cap = proxy->cap;
if ((cap & PR_CAP_LISTEN) == PR_CAP_LISTEN)
return "listener";
else if (cap & PR_CAP_FE)
return "frontend";
else if (cap & PR_CAP_BE)
return "backend";
else if (cap & PR_CAP_RS)
return "ruleset";
else
return "proxy";
}
/*
* This function creates all proxy sockets. It should be done very early,
* typically before privileges are dropped. The sockets will be registered
* but not added to any fd_set, in order not to loose them across the fork().
* The proxies also start in IDLE state, meaning that it will be
* maintain_proxies that will finally complete their loading.
*
* Its return value is composed from ERR_NONE, ERR_RETRYABLE and ERR_FATAL.
* Retryable errors will only be printed if <verbose> is not zero.
*/
int start_proxies(int verbose)
{
struct proxy *curproxy;
struct listener *listener;
int err = ERR_NONE;
int fd, pxerr;
for (curproxy = proxy; curproxy != NULL; curproxy = curproxy->next) {
if (curproxy->state != PR_STNEW)
continue; /* already initialized */
pxerr = 0;
for (listener = curproxy->listen; listener != NULL; listener = listener->next) {
if (listener->fd != -1)
continue; /* already initialized */
if ((fd = socket(listener->addr.ss_family, SOCK_STREAM, IPPROTO_TCP)) == -1) {
if (verbose)
Alert("cannot create listening socket for proxy %s. Aborting.\n",
curproxy->id);
err |= ERR_RETRYABLE;
pxerr |= 1;
continue;
}
if (fd >= global.maxsock) {
Alert("socket(): not enough free sockets for proxy %s. Raise -n argument. Aborting.\n",
curproxy->id);
close(fd);
err |= ERR_FATAL;
pxerr |= 1;
break;
}
if ((fcntl(fd, F_SETFL, O_NONBLOCK) == -1) ||
(setsockopt(fd, IPPROTO_TCP, TCP_NODELAY,
(char *) &one, sizeof(one)) == -1)) {
Alert("cannot make socket non-blocking for proxy %s. Aborting.\n",
curproxy->id);
close(fd);
err |= ERR_FATAL;
pxerr |= 1;
break;
}
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *) &one, sizeof(one)) == -1) {
Alert("cannot do so_reuseaddr for proxy %s. Continuing.\n",
curproxy->id);
}
#ifdef SO_REUSEPORT
/* OpenBSD supports this. As it's present in old libc versions of Linux,
* it might return an error that we will silently ignore.
*/
setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, (char *) &one, sizeof(one));
#endif
if (bind(fd,
(struct sockaddr *)&listener->addr,
listener->addr.ss_family == AF_INET6 ?
sizeof(struct sockaddr_in6) :
sizeof(struct sockaddr_in)) == -1) {
if (verbose)
Alert("cannot bind socket for proxy %s. Aborting.\n",
curproxy->id);
close(fd);
err |= ERR_RETRYABLE;
pxerr |= 1;
continue;
}
if (listen(fd, curproxy->maxconn) == -1) {
if (verbose)
Alert("cannot listen to socket for proxy %s. Aborting.\n",
curproxy->id);
close(fd);
err |= ERR_RETRYABLE;
pxerr |= 1;
continue;
}
/* the socket is ready */
listener->fd = fd;
/* the function for the accept() event */
fd_insert(fd);
fdtab[fd].cb[DIR_RD].f = &event_accept;
fdtab[fd].cb[DIR_WR].f = NULL; /* never called */
fdtab[fd].cb[DIR_RD].b = fdtab[fd].cb[DIR_WR].b = NULL;
fdtab[fd].owner = (struct task *)curproxy; /* reference the proxy instead of a task */
fdtab[fd].state = FD_STLISTEN;
fdtab[fd].ev = 0;
listeners++;
}
if (!pxerr) {
curproxy->state = PR_STIDLE;
send_log(curproxy, LOG_NOTICE, "Proxy %s started.\n", curproxy->id);
}
}
return err;
}
/*
* this function enables proxies when there are enough free sessions,
* or stops them when the table is full. It is designed to be called from the
* select_loop(). It returns the time left before next expiration event
* during stop time, TIME_ETERNITY otherwise.
*/
int maintain_proxies(void)
{
struct proxy *p;
struct listener *l;
int tleft; /* time left */
p = proxy;
tleft = TIME_ETERNITY; /* infinite time */
/* if there are enough free sessions, we'll activate proxies */
if (actconn < global.maxconn) {
while (p) {
if (p->feconn < p->maxconn) {
if (p->state == PR_STIDLE) {
for (l = p->listen; l != NULL; l = l->next) {
EV_FD_SET(l->fd, DIR_RD);
}
p->state = PR_STRUN;
}
}
else {
if (p->state == PR_STRUN) {
for (l = p->listen; l != NULL; l = l->next) {
EV_FD_CLR(l->fd, DIR_RD);
}
p->state = PR_STIDLE;
}
}
p = p->next;
}
}
else { /* block all proxies */
while (p) {
if (p->state == PR_STRUN) {
for (l = p->listen; l != NULL; l = l->next) {
EV_FD_CLR(l->fd, DIR_RD);
}
p->state = PR_STIDLE;
}
p = p->next;
}
}
if (stopping) {
p = proxy;
while (p) {
if (p->state != PR_STSTOPPED) {
int t;
t = tv_ms_remain2(&now, &p->stop_time);
if (t == 0) {
Warning("Proxy %s stopped.\n", p->id);
send_log(p, LOG_WARNING, "Proxy %s stopped.\n", p->id);
for (l = p->listen; l != NULL; l = l->next) {
fd_delete(l->fd);
listeners--;
}
p->state = PR_STSTOPPED;
}
else {
tleft = MINTIME(t, tleft);
}
}
p = p->next;
}
}
return tleft;
}
/*
* this function disables health-check servers so that the process will quickly be ignored
* by load balancers. Note that if a proxy was already in the PAUSED state, then its grace
* time will not be used since it would already not listen anymore to the socket.
*/
void soft_stop(void)
{
struct proxy *p;
stopping = 1;
p = proxy;
tv_now(&now); /* else, the old time before select will be used */
while (p) {
if (p->state != PR_STSTOPPED) {
Warning("Stopping proxy %s in %d ms.\n", p->id, p->grace);
send_log(p, LOG_WARNING, "Stopping proxy %s in %d ms.\n", p->id, p->grace);
tv_ms_add(&p->stop_time, &now, p->grace);
}
p = p->next;
}
}
/*
* Linux unbinds the listen socket after a SHUT_RD, and ignores SHUT_WR.
* Solaris refuses either shutdown().
* OpenBSD ignores SHUT_RD but closes upon SHUT_WR and refuses to rebind.
* So a common validation path involves SHUT_WR && listen && SHUT_RD.
* If disabling at least one listener returns an error, then the proxy
* state is set to PR_STERROR because we don't know how to resume from this.
*/
void pause_proxy(struct proxy *p)
{
struct listener *l;
for (l = p->listen; l != NULL; l = l->next) {
if (shutdown(l->fd, SHUT_WR) == 0 &&
listen(l->fd, p->maxconn) == 0 &&
shutdown(l->fd, SHUT_RD) == 0) {
EV_FD_CLR(l->fd, DIR_RD);
if (p->state != PR_STERROR)
p->state = PR_STPAUSED;
}
else
p->state = PR_STERROR;
}
}
/*
* This function temporarily disables listening so that another new instance
* can start listening. It is designed to be called upon reception of a
* SIGTTOU, after which either a SIGUSR1 can be sent to completely stop
* the proxy, or a SIGTTIN can be sent to listen again.
*/
void pause_proxies(void)
{
int err;
struct proxy *p;
err = 0;
p = proxy;
tv_now(&now); /* else, the old time before select will be used */
while (p) {
if (p->state != PR_STERROR &&
p->state != PR_STSTOPPED &&
p->state != PR_STPAUSED) {
Warning("Pausing proxy %s.\n", p->id);
send_log(p, LOG_WARNING, "Pausing proxy %s.\n", p->id);
pause_proxy(p);
if (p->state != PR_STPAUSED) {
err |= 1;
Warning("Proxy %s failed to enter pause mode.\n", p->id);
send_log(p, LOG_WARNING, "Proxy %s failed to enter pause mode.\n", p->id);
}
}
p = p->next;
}
if (err) {
Warning("Some proxies refused to pause, performing soft stop now.\n");
send_log(p, LOG_WARNING, "Some proxies refused to pause, performing soft stop now.\n");
soft_stop();
}
}
/*
* This function reactivates listening. This can be used after a call to
* sig_pause(), for example when a new instance has failed starting up.
* It is designed to be called upon reception of a SIGTTIN.
*/
void listen_proxies(void)
{
struct proxy *p;
struct listener *l;
p = proxy;
tv_now(&now); /* else, the old time before select will be used */
while (p) {
if (p->state == PR_STPAUSED) {
Warning("Enabling proxy %s.\n", p->id);
send_log(p, LOG_WARNING, "Enabling proxy %s.\n", p->id);
for (l = p->listen; l != NULL; l = l->next) {
if (listen(l->fd, p->maxconn) == 0) {
if (actconn < global.maxconn && p->feconn < p->maxconn) {
EV_FD_SET(l->fd, DIR_RD);
p->state = PR_STRUN;
}
else
p->state = PR_STIDLE;
} else {
int port;
if (l->addr.ss_family == AF_INET6)
port = ntohs(((struct sockaddr_in6 *)(&l->addr))->sin6_port);
else
port = ntohs(((struct sockaddr_in *)(&l->addr))->sin_port);
Warning("Port %d busy while trying to enable proxy %s.\n",
port, p->id);
send_log(p, LOG_WARNING, "Port %d busy while trying to enable proxy %s.\n",
port, p->id);
/* Another port might have been enabled. Let's stop everything. */
pause_proxy(p);
break;
}
}
}
p = p->next;
}
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/