usr.sbin/rdate/rfc868time.c

   1 /*      $OpenBSD: src/usr.sbin/rdate/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 /*      $DragonFly: src/usr.sbin/rdate/rfc868time.c,v 1.1 2004/12/01 15:04:43 joerg Exp $ */
   4
   5 /*
   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 /* Obviously it is not just for SNTP clients... */
  57 #include "ntpleaps.h"
  58
  59 #include "rdate.h"
  60
  61 /* seconds from midnight Jan 1900 - 1970 */
  62 #define DIFFERENCE      2208988800UL
  63
  64 void
  65 rfc868time_client(const char *hostname, int family, struct timeval *new,
  66                   struct timeval *adjust, int leapflag)
  67 {
  68         struct addrinfo hints, *res0, *res;
  69         struct timeval old;
  70         uint32_t tim;   /* RFC 868 states clearly this is an uint32 */
  71         int s;
  72         int error;
  73         uint64_t td;
  74
  75         memset(&hints, 0, sizeof(hints));
  76         hints.ai_family = family;
  77         hints.ai_socktype = SOCK_STREAM;
  78         /* XXX what about rfc868 UDP
  79          * probably not due to the Y2038 issue  -mirabile */
  80         error = getaddrinfo(hostname, "time", &hints, &res0);
  81         if (error)
  82                 errx(1, "%s: %s", hostname, gai_strerror(error));
  83
  84         s = -1;
  85         for (res = res0; res; res = res->ai_next) {
  86                 s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
  87                 if (s < 0)
  88                         continue;
  89
  90                 if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
  91                         close(s);
  92                         s = -1;
  93                         continue;
  94                 }
  95
  96                 break;
  97         }
  98         if (s < 0)
  99                 err(1, "Could not connect socket");
 100         freeaddrinfo(res0);
 101
 102         if (read(s, &tim, sizeof(tim)) != sizeof(tim))
 103                 err(1, "Could not read data");
 104
 105         close(s);
 106         tim = ntohl(tim) - DIFFERENCE;
 107
 108         if (gettimeofday(&old, NULL) == -1)
 109                 err(1, "Could not get local time of day");
 110
 111         td = SEC_TO_TAI64(old.tv_sec);
 112         if (leapflag)
 113                 ntpleaps_sub(&td);
 114
 115         adjust->tv_sec = tim - TAI64_TO_SEC(td);
 116         adjust->tv_usec = 0;
 117
 118         new->tv_sec = old.tv_sec + adjust->tv_sec;
 119         new->tv_usec = 0;
 120 }