NetBSD/libexec/talkd/talkd.c

164 lines
4.4 KiB
C

/* $NetBSD: talkd.c,v 1.21 2009/03/16 01:04:32 lukem Exp $ */
/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1983, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)talkd.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: talkd.c,v 1.21 2009/03/16 01:04:32 lukem Exp $");
#endif
#endif /* not lint */
/*
* The top level of the daemon, the format is heavily borrowed
* from rwhod.c. Basically: find out who and where you are;
* disconnect all descriptors and ttys, and then endless
* loop on waiting for and processing requests
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <protocols/talkd.h>
#include <errno.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
#include "extern.h"
CTL_MSG request;
CTL_RESPONSE response;
int sockt = STDIN_FILENO;
int debug = 0;
int logging = 0;
time_t lastmsgtime;
char hostname[MAXHOSTNAMELEN + 1];
#define TIMEOUT 30
#define MAXIDLE 120
static void timeout(int);
int main(int, char *[]);
int
main(int argc, char *argv[])
{
CTL_MSG *mp = &request;
int cc, ch;
struct sockaddr ctl_addr;
openlog("talkd", LOG_PID, LOG_DAEMON);
while ((ch = getopt(argc, argv, "dl")) != -1)
switch (ch) {
case 'd':
debug = 1;
break;
case 'l':
logging = 1;
break;
default:
syslog(LOG_ERR, "Usage: %s [-dl]", getprogname());
exit(1);
}
if (gethostname(hostname, sizeof hostname) < 0) {
syslog(LOG_ERR, "gethostname: %m");
_exit(1);
}
hostname[MAXHOSTNAMELEN] = '\0'; /* ensure null termination */
if (chdir(_PATH_DEV) < 0) {
syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
_exit(1);
}
signal(SIGALRM, timeout);
alarm(TIMEOUT);
for (;;) {
memset(&response, 0, sizeof(response));
cc = recv(0, (char *)mp, sizeof (*mp), 0);
if (cc != sizeof (*mp)) {
if (cc < 0 && errno != EINTR)
syslog(LOG_WARNING, "recv: %m");
continue;
}
mp->l_name[sizeof(mp->l_name) - 1] = '\0';
mp->r_name[sizeof(mp->r_name) - 1] = '\0';
mp->r_tty[sizeof(mp->r_tty) - 1] = '\0';
lastmsgtime = time(0);
process_request(mp, &response);
tsa2sa(&ctl_addr, &mp->ctl_addr);
if (ctl_addr.sa_family != AF_INET)
continue;
/* can block here, is this what I want? */
cc = sendto(sockt, (char *)&response, sizeof (response), 0,
&ctl_addr, sizeof (ctl_addr));
if (cc != sizeof (response))
syslog(LOG_WARNING, "sendto: %m");
}
}
void
timeout(int n)
{
int save_errno = errno;
if (time(0) - lastmsgtime >= MAXIDLE)
_exit(0);
alarm(TIMEOUT);
errno = save_errno;
}
void
tsa2sa(struct sockaddr *sa, const struct talkd_sockaddr *tsa)
{
(void)memcpy(sa, tsa, sizeof(*tsa));
sa->sa_len = sizeof(*tsa);
sa->sa_family = tsa->sa_family;
}