blob: 954982ae958a2b68ec93a34ef6a2a7740c75b8c6 [file] [log] [blame]
Eric Andersen6ab22022000-08-21 23:04:00 +00001/* vi: set sw=4 ts=4: */
2/*
3 * The Rdate command will ask a time server for the RFC 868 time
4 * and optionally set the system time.
5 *
6 * by Sterling Huxley <sterling@europa.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22*/
23
Eric Andersen3570a342000-09-25 21:45:58 +000024#include "busybox.h"
Eric Andersen6ab22022000-08-21 23:04:00 +000025#define BB_DECLARE_EXTERN
26#include "messages.c"
27#include <sys/time.h>
28#include <sys/types.h>
29#include <sys/socket.h>
30#include <netinet/in.h>
31#include <netdb.h>
32#include <stdio.h>
33#include <getopt.h>
34
35
Mark Whitley59ab0252001-01-23 22:30:04 +000036static const int RFC_868_BIAS = 2208988800UL;
Eric Andersen6ab22022000-08-21 23:04:00 +000037
38int setdate= 0;
39int printdate= 0;
40
41time_t askremotedate(char *host)
42{
43 struct hostent *h;
44 struct sockaddr_in sin;
45 struct servent *tserv;
46 unsigned long int nett, localt;
47 int fd;
48
49 if (!(h = gethostbyname(host))) { /* get the IP addr */
Matt Kraai1fa1ade2000-12-18 03:57:16 +000050 perror_msg("%s", host);
Eric Andersen6ab22022000-08-21 23:04:00 +000051 return(-1);
52 }
53 if ((tserv = getservbyname("time", "tcp")) == NULL) { /* find port # */
Matt Kraai1fa1ade2000-12-18 03:57:16 +000054 perror_msg("%s", "time");
Eric Andersen6ab22022000-08-21 23:04:00 +000055 return(-1);
56 }
57 if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { /* get net connection */
Matt Kraai1fa1ade2000-12-18 03:57:16 +000058 perror_msg("%s", "socket");
Eric Andersen6ab22022000-08-21 23:04:00 +000059 return(-1);
60 }
61
62 memcpy(&sin.sin_addr, h->h_addr, sizeof(sin.sin_addr));
63 sin.sin_port= tserv->s_port;
64 sin.sin_family = AF_INET;
65
Eric Andersenba35b982000-09-21 04:05:38 +000066 if (connect(fd, (struct sockaddr *)&sin, sizeof(sin)) < 0) { /* connect to time server */
Matt Kraai1fa1ade2000-12-18 03:57:16 +000067 perror_msg("%s", host);
Eric Andersen6ab22022000-08-21 23:04:00 +000068 close(fd);
69 return(-1);
70 }
Eric Andersend1ee7e32000-10-26 07:57:27 +000071 if (read(fd, (void *)&nett, 4) != 4) { /* read time from server */
Eric Andersen6ab22022000-08-21 23:04:00 +000072 close(fd);
Mark Whitleyf57c9442000-12-07 19:56:48 +000073 error_msg("%s did not send the complete time\n", host);
Eric Andersen6ab22022000-08-21 23:04:00 +000074 }
75 close(fd);
76
77 /* convert from network byte order to local byte order.
78 * RFC 868 time is the number of seconds
79 * since 00:00 (midnight) 1 January 1900 GMT
80 * the RFC 868 time 2,208,988,800 corresponds to 00:00 1 Jan 1970 GMT
81 * Subtract the RFC 868 time to get Linux epoch
82 */
83 localt= ntohl(nett) - RFC_868_BIAS;
84
85 return(localt);
86}
87
88int rdate_main(int argc, char **argv)
89{
90 time_t time;
91 int opt;
92
93 /* Interpret command line args */
94 /* do special-case option parsing */
95 if (argv[1] && (strcmp(argv[1], "--help") == 0))
96 usage(rdate_usage);
97
98 /* do normal option parsing */
99 while ((opt = getopt(argc, argv, "Hsp")) > 0) {
100 switch (opt) {
101 default:
102 case 'H':
103 usage(rdate_usage);
Eric Andersen6ab22022000-08-21 23:04:00 +0000104 break;
105 case 's':
106 setdate++;
107 break;
108 case 'p':
109 printdate++;
110 break;
111 }
112 }
113
114 /* the default action is to set the date */
115 if (printdate==0 && setdate==0) setdate++;
116
117 if (optind == argc) {
118 usage(rdate_usage);
Eric Andersen6ab22022000-08-21 23:04:00 +0000119 }
120
121 if ((time= askremotedate(argv[optind])) == (time_t)-1) {
Matt Kraai3e856ce2000-12-01 02:55:13 +0000122 return EXIT_FAILURE;
Eric Andersen6ab22022000-08-21 23:04:00 +0000123 }
124 if (setdate) {
125 if (stime(&time) < 0)
Matt Kraai1fa1ade2000-12-18 03:57:16 +0000126 perror_msg_and_die("Could not set time of day");
Eric Andersen6ab22022000-08-21 23:04:00 +0000127 }
128 if (printdate) {
Matt Kraai12f417e2001-01-18 02:57:08 +0000129 printf("%s", ctime(&time));
Eric Andersen6ab22022000-08-21 23:04:00 +0000130 }
131
Matt Kraai3e856ce2000-12-01 02:55:13 +0000132 return EXIT_SUCCESS;
Eric Andersen6ab22022000-08-21 23:04:00 +0000133}