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/*
* (C) 2006-2007 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Description: run and init functions
*/
#include "conntrackd.h"
#include "netlink.h"
#include "ignore.h"
#include "log.h"
#include "alarm.h"
#include "fds.h"
#include <errno.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
#include <string.h>
void killer(int foo)
{
/* no signals while handling signals */
sigprocmask(SIG_BLOCK, &STATE(block), NULL);
nfct_close(STATE(event));
nfct_close(STATE(dump));
ignore_pool_destroy(STATE(ignore_pool));
local_server_destroy(&STATE(local));
STATE(mode)->kill();
unlink(CONFIG(lockfile));
dlog(LOG_NOTICE, "---- shutdown received ----");
close_log();
sigprocmask(SIG_UNBLOCK, &STATE(block), NULL);
exit(0);
}
static void child(int foo)
{
while(wait(NULL) > 0);
}
void local_handler(int fd, void *data)
{
int ret;
int type;
ret = read(fd, &type, sizeof(type));
if (ret == -1) {
dlog(LOG_ERR, "can't read from unix socket");
return;
}
if (ret == 0)
return;
switch(type) {
case FLUSH_MASTER:
dlog(LOG_WARNING, "`conntrackd -F' is deprecated. "
"Use conntrack -F instead.");
if (fork() == 0) {
execlp("conntrack", "conntrack", "-F", NULL);
exit(EXIT_SUCCESS);
}
return;
case RESYNC_MASTER:
dlog(LOG_NOTICE, "resync with master table");
nl_dump_conntrack_table();
return;
}
if (!STATE(mode)->local(fd, type, data))
dlog(LOG_WARNING, "unknown local request %d", type);
}
int
init(void)
{
if (CONFIG(flags) & CTD_STATS_MODE)
STATE(mode) = &stats_mode;
else if (CONFIG(flags) & CTD_SYNC_MODE)
STATE(mode) = &sync_mode;
else {
fprintf(stderr, "WARNING: No running mode specified. "
"Defaulting to statistics mode.\n");
CONFIG(flags) |= CTD_STATS_MODE;
STATE(mode) = &stats_mode;
}
/* Initialization */
if (STATE(mode)->init() == -1) {
dlog(LOG_ERR, "initialization failed");
return -1;
}
/* local UNIX socket */
if (local_server_create(&STATE(local), &CONFIG(local)) == -1) {
dlog(LOG_ERR, "can't open unix socket!");
return -1;
}
if (nl_init_event_handler() == -1) {
dlog(LOG_ERR, "can't open netlink handler: %s",
strerror(errno));
dlog(LOG_ERR, "no ctnetlink kernel support?");
return -1;
}
if (nl_init_dump_handler() == -1) {
dlog(LOG_ERR, "can't open netlink handler: %s",
strerror(errno));
dlog(LOG_ERR, "no ctnetlink kernel support?");
return -1;
}
STATE(fds) = create_fds();
if (STATE(fds) == NULL) {
dlog(LOG_ERR, "can't create file descriptor pool");
return -1;
}
register_fd(STATE(local).fd, STATE(fds));
register_fd(nfct_fd(STATE(event)), STATE(fds));
if (STATE(mode)->register_fds &&
STATE(mode)->register_fds(STATE(fds)) == -1) {
dlog(LOG_ERR, "fds registration failed");
return -1;
}
/* Signals handling */
sigemptyset(&STATE(block));
sigaddset(&STATE(block), SIGTERM);
sigaddset(&STATE(block), SIGINT);
sigaddset(&STATE(block), SIGCHLD);
if (signal(SIGINT, killer) == SIG_ERR)
return -1;
if (signal(SIGTERM, killer) == SIG_ERR)
return -1;
/* ignore connection reset by peer */
if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
return -1;
if (signal(SIGCHLD, child) == SIG_ERR)
return -1;
dlog(LOG_NOTICE, "initialization completed");
return 0;
}
static void __run(struct timeval *next_alarm)
{
int ret;
fd_set readfds = STATE(fds)->readfds;
ret = select(STATE(fds)->maxfd + 1, &readfds, NULL, NULL, next_alarm);
if (ret == -1) {
/* interrupted syscall, retry */
if (errno == EINTR)
return;
dlog(LOG_WARNING, "select failed: %s", strerror(errno));
return;
}
/* signals are racy */
sigprocmask(SIG_BLOCK, &STATE(block), NULL);
/* order received via UNIX socket */
if (FD_ISSET(STATE(local).fd, &readfds))
do_local_server_step(&STATE(local), NULL, local_handler);
/* conntrack event has happened */
if (FD_ISSET(nfct_fd(STATE(event)), &readfds)) {
while ((ret = nfct_catch(STATE(event))) != -1);
if (ret == -1) {
switch(errno) {
case ENOBUFS:
/*
* It seems that ctnetlink can't back off,
* it's likely that we're losing events.
* Solution: duplicate the socket buffer
* size and resync with master conntrack table.
*/
nl_resize_socket_buffer(STATE(event));
/* XXX: schedule overrun call via alarm */
STATE(mode)->overrun();
break;
case ENOENT:
/*
* We received a message from another
* netfilter subsystem that we are not
* interested in. Just ignore it.
*/
break;
case EAGAIN:
break;
default:
dlog(LOG_WARNING,
"event catch says: %s", strerror(errno));
break;
}
}
}
if (STATE(mode)->run)
STATE(mode)->run(&readfds);
sigprocmask(SIG_UNBLOCK, &STATE(block), NULL);
}
void __attribute__((noreturn))
run(void)
{
struct timeval next_alarm;
struct timeval *next = NULL;
while(1) {
sigprocmask(SIG_BLOCK, &STATE(block), NULL);
if (next != NULL && !timerisset(next))
next = do_alarm_run(&next_alarm);
else
next = get_next_alarm_run(&next_alarm);
sigprocmask(SIG_UNBLOCK, &STATE(block), NULL);
__run(next);
}
}
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