1 /*	$OpenBSD: rfc868time.c,v 1.6 2004/02/16 21:25:41 jakob Exp $	*/
2 /*	$NetBSD: rdate.c,v 1.4 1996/03/16 12:37:45 pk Exp $	*/
3 
4 /*
5  * Copyright (c) 2005 Thorsten Glaser
6  * Copyright (c) 1994 Christos Zoulas
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by Christos Zoulas.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 /*
36  * rdate.c: Set the date from the specified host
37  *
38  *	Uses the rfc868 time protocol at socket 37 (tcp).
39  *	Time is returned as the number of seconds since
40  *	midnight January 1st 1900.
41  */
42 
43 #include <sys/param.h>
44 #include <sys/socket.h>
45 #include <sys/time.h>
46 #include <netinet/in.h>
47 
48 #include <stdio.h>
49 #include <ctype.h>
50 #include <err.h>
51 #include <string.h>
52 #include <netdb.h>
53 #include <unistd.h>
54 #include <time.h>
55 
56 #include "rdate.h"
57 
58 __RCSID("$MirOS: src/usr.sbin/rdate/rfc868time.c,v 1.6 2008/11/08 23:04:56 tg Exp $");
59 #ifdef MirBSD
60 __RCSID("$NetBSD: rdate.c,v 1.3 1996/02/22 06:59:18 thorpej Exp $");
61 __RCSID("$OpenBSD: rfc868time.c,v 1.6 2004/02/16 21:25:41 jakob Exp $");
62 #endif
63 
64 /* seconds from midnight Jan 1900 - 1970 */
65 #define DIFFERENCE 2208988800UL
66 
67 void
rfc868time_client(const char * hostname,int family,struct timeval * new,struct timeval * adjust)68 rfc868time_client (const char *hostname, int family, struct timeval *new,
69     struct timeval *adjust)
70 {
71 	struct addrinfo hints, *res0, *res;
72 	struct timeval old;
73 	u_int32_t tim;	/* RFC 868 states clearly this is an uint32 */
74 	int s;
75 	int error;
76 
77 	memset(&hints, 0, sizeof(hints));
78 	hints.ai_family = family;
79 	hints.ai_socktype = SOCK_STREAM;
80 	/* XXX what about rfc868 UDP
81 	 * probably not due to the Y2038 issue  -mirabilos */
82 	error = getaddrinfo(hostname, "time", &hints, &res0);
83 	if (error) {
84 		errx(1, "%s: %s", hostname, gai_strerror(error));
85 		/*NOTREACHED*/
86 	}
87 
88 	s = -1;
89 	for (res = res0; res; res = res->ai_next) {
90 		s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
91 		if (s < 0)
92 			continue;
93 
94 		if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
95 			close(s);
96 			s = -1;
97 			continue;
98 		}
99 
100 		break;
101 	}
102 	if (s < 0)
103 		err(1, "Could not connect socket");
104 	freeaddrinfo(res0);
105 
106 	if (read(s, &tim, sizeof(tim)) != sizeof(tim))
107 		err(1, "Could not read data");
108 
109 	(void) close(s);
110 	tim = ntohl(tim) - DIFFERENCE;
111 
112 	if (gettimeofday(&old, NULL) == -1)
113 		err(1, "Could not get local time of day");
114 
115 	adjust->tv_sec = tim - old.tv_sec;
116 	adjust->tv_usec = 0;
117 
118 	new->tv_sec = old.tv_sec + adjust->tv_sec;
119 	new->tv_usec = 0;
120 }
121