netdate.c revision 26362
1/*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $Id: netdate.c,v 1.7 1997/03/10 19:49:03 guido Exp $ 34 */ 35 36#ifndef lint 37static char const sccsid[] = "@(#)netdate.c 8.1 (Berkeley) 5/31/93"; 38#endif /* not lint */ 39 40#include <sys/param.h> 41#include <sys/time.h> 42#include <sys/socket.h> 43 44#include <netinet/in.h> 45#include <netdb.h> 46#define TSPTYPES 47#include <protocols/timed.h> 48 49#include <err.h> 50#include <errno.h> 51#include <stdio.h> 52#include <string.h> 53#include <unistd.h> 54 55#include "extern.h" 56 57#define WAITACK 2 /* seconds */ 58#define WAITDATEACK 5 /* seconds */ 59 60extern int retval; 61 62/* 63 * Set the date in the machines controlled by timedaemons by communicating the 64 * new date to the local timedaemon. If the timedaemon is in the master state, 65 * it performs the correction on all slaves. If it is in the slave state, it 66 * notifies the master that a correction is needed. 67 * Returns 0 on success. Returns > 0 on failure, setting retval to 2; 68 */ 69int 70netsettime(tval) 71 time_t tval; 72{ 73 struct timeval tout; 74 struct servent *sp; 75 struct tsp msg; 76 struct sockaddr_in sin, dest, from; 77 fd_set ready; 78 long waittime; 79 int s, length, port, timed_ack, found, err; 80 char hostname[MAXHOSTNAMELEN]; 81 82 if ((sp = getservbyname("timed", "udp")) == NULL) { 83 warnx("udp/timed: unknown service"); 84 return (retval = 2); 85 } 86 87 dest.sin_port = sp->s_port; 88 dest.sin_family = AF_INET; 89 dest.sin_addr.s_addr = htonl((u_long)INADDR_ANY); 90 s = socket(AF_INET, SOCK_DGRAM, 0); 91 if (s < 0) { 92 if (errno != EPROTONOSUPPORT) 93 warn("timed"); 94 return (retval = 2); 95 } 96 97 memset(&sin, 0, sizeof(sin)); 98 sin.sin_family = AF_INET; 99 for (port = IPPORT_RESERVED - 1; port > IPPORT_RESERVED / 2; port--) { 100 sin.sin_port = htons((u_short)port); 101 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0) 102 break; 103 if (errno == EADDRINUSE) 104 continue; 105 if (errno != EADDRNOTAVAIL) 106 warn("bind"); 107 goto bad; 108 } 109 if (port == IPPORT_RESERVED / 2) { 110 warnx("all ports in use"); 111 goto bad; 112 } 113 msg.tsp_type = TSP_SETDATE; 114 msg.tsp_vers = TSPVERSION; 115 if (gethostname(hostname, sizeof(hostname))) { 116 warn("gethostname"); 117 goto bad; 118 } 119 (void)strncpy(msg.tsp_name, hostname, sizeof(msg.tsp_name) - 1); 120 msg.tsp_name[sizeof(msg.tsp_name) - 1] = '\0'; 121 msg.tsp_seq = htons((u_short)0); 122 msg.tsp_time.tv_sec = htonl((u_long)tval); 123 msg.tsp_time.tv_usec = htonl((u_long)0); 124 length = sizeof(struct sockaddr_in); 125 if (connect(s, (struct sockaddr *)&dest, length) < 0) { 126 warn("connect"); 127 goto bad; 128 } 129 if (send(s, (char *)&msg, sizeof(struct tsp), 0) < 0) { 130 if (errno != ECONNREFUSED) 131 warn("send"); 132 goto bad; 133 } 134 135 timed_ack = -1; 136 waittime = WAITACK; 137loop: 138 tout.tv_sec = waittime; 139 tout.tv_usec = 0; 140 141 FD_ZERO(&ready); 142 FD_SET(s, &ready); 143 found = select(FD_SETSIZE, &ready, (fd_set *)0, (fd_set *)0, &tout); 144 145 length = sizeof(err); 146 if (!getsockopt(s, 147 SOL_SOCKET, SO_ERROR, (char *)&err, &length) && err) { 148 if (err != ECONNREFUSED) 149 warn("send (delayed error)"); 150 goto bad; 151 } 152 153 if (found > 0 && FD_ISSET(s, &ready)) { 154 length = sizeof(struct sockaddr_in); 155 if (recvfrom(s, &msg, sizeof(struct tsp), 0, 156 (struct sockaddr *)&from, &length) < 0) { 157 if (errno != ECONNREFUSED) 158 warn("recvfrom"); 159 goto bad; 160 } 161 msg.tsp_seq = ntohs(msg.tsp_seq); 162 msg.tsp_time.tv_sec = ntohl(msg.tsp_time.tv_sec); 163 msg.tsp_time.tv_usec = ntohl(msg.tsp_time.tv_usec); 164 switch (msg.tsp_type) { 165 case TSP_ACK: 166 timed_ack = TSP_ACK; 167 waittime = WAITDATEACK; 168 goto loop; 169 case TSP_DATEACK: 170 (void)close(s); 171 return (0); 172 default: 173 warnx("wrong ack received from timed: %s", 174 tsptype[msg.tsp_type]); 175 timed_ack = -1; 176 break; 177 } 178 } 179 if (timed_ack == -1) 180 warnx("can't reach time daemon, time set locally"); 181 182bad: 183 (void)close(s); 184 return (retval = 2); 185} 186