freebsd-skq/bin/date/netdate.c
2002-06-09 04:18:45 +00:00

187 lines
5.4 KiB
C

/*-
* Copyright (c) 1990, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)netdate.c 8.1 (Berkeley) 5/31/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#define TSPTYPES
#include <protocols/timed.h>
#include <err.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include "extern.h"
#define WAITACK 2 /* seconds */
#define WAITDATEACK 5 /* seconds */
extern int retval;
/*
* Set the date in the machines controlled by timedaemons by communicating the
* new date to the local timedaemon. If the timedaemon is in the master state,
* it performs the correction on all slaves. If it is in the slave state, it
* notifies the master that a correction is needed.
* Returns 0 on success. Returns > 0 on failure, setting retval to 2;
*/
int
netsettime(time_t tval)
{
struct timeval tout;
struct servent *sp;
struct tsp msg;
struct sockaddr_in lsin, dest, from;
fd_set ready;
long waittime;
int s, port, timed_ack, found, lerr;
socklen_t length;
char hostname[MAXHOSTNAMELEN];
if ((sp = getservbyname("timed", "udp")) == NULL) {
warnx("udp/timed: unknown service");
return (retval = 2);
}
dest.sin_port = sp->s_port;
dest.sin_family = AF_INET;
dest.sin_addr.s_addr = htonl((u_long)INADDR_ANY);
s = socket(AF_INET, SOCK_DGRAM, 0);
if (s < 0) {
if (errno != EPROTONOSUPPORT)
warn("timed");
return (retval = 2);
}
memset(&lsin, 0, sizeof(lsin));
lsin.sin_family = AF_INET;
for (port = IPPORT_RESERVED - 1; port > IPPORT_RESERVED / 2; port--) {
lsin.sin_port = htons((u_short)port);
if (bind(s, (struct sockaddr *)&lsin, sizeof(lsin)) >= 0)
break;
if (errno == EADDRINUSE)
continue;
if (errno != EADDRNOTAVAIL)
warn("bind");
goto bad;
}
if (port == IPPORT_RESERVED / 2) {
warnx("all ports in use");
goto bad;
}
msg.tsp_type = TSP_SETDATE;
msg.tsp_vers = TSPVERSION;
if (gethostname(hostname, sizeof(hostname))) {
warn("gethostname");
goto bad;
}
(void)strncpy(msg.tsp_name, hostname, sizeof(msg.tsp_name) - 1);
msg.tsp_name[sizeof(msg.tsp_name) - 1] = '\0';
msg.tsp_seq = htons((u_short)0);
msg.tsp_time.tv_sec = htonl((u_long)tval);
msg.tsp_time.tv_usec = htonl((u_long)0);
length = sizeof(struct sockaddr_in);
if (connect(s, (struct sockaddr *)&dest, length) < 0) {
warn("connect");
goto bad;
}
if (send(s, (char *)&msg, sizeof(struct tsp), 0) < 0) {
if (errno != ECONNREFUSED)
warn("send");
goto bad;
}
timed_ack = -1;
waittime = WAITACK;
loop:
tout.tv_sec = waittime;
tout.tv_usec = 0;
FD_ZERO(&ready);
FD_SET(s, &ready);
found = select(FD_SETSIZE, &ready, (fd_set *)0, (fd_set *)0, &tout);
length = sizeof(lerr);
if (!getsockopt(s,
SOL_SOCKET, SO_ERROR, (char *)&lerr, &length) && lerr) {
if (lerr != ECONNREFUSED)
warnc(lerr, "send (delayed error)");
goto bad;
}
if (found > 0 && FD_ISSET(s, &ready)) {
length = sizeof(struct sockaddr_in);
if (recvfrom(s, &msg, sizeof(struct tsp), 0,
(struct sockaddr *)&from, &length) < 0) {
if (errno != ECONNREFUSED)
warn("recvfrom");
goto bad;
}
msg.tsp_seq = ntohs(msg.tsp_seq);
msg.tsp_time.tv_sec = ntohl(msg.tsp_time.tv_sec);
msg.tsp_time.tv_usec = ntohl(msg.tsp_time.tv_usec);
switch (msg.tsp_type) {
case TSP_ACK:
timed_ack = TSP_ACK;
waittime = WAITDATEACK;
goto loop;
case TSP_DATEACK:
(void)close(s);
return (0);
default:
warnx("wrong ack received from timed: %s",
tsptype[msg.tsp_type]);
timed_ack = -1;
break;
}
}
if (timed_ack == -1)
warnx("can't reach time daemon, time set locally");
bad:
(void)close(s);
return (retval = 2);
}