1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28/*	  All Rights Reserved  	*/
29
30/*
31 * University Copyright- Copyright (c) 1982, 1986, 1988
32 * The Regents of the University of California
33 * All Rights Reserved
34 *
35 * University Acknowledgment- Portions of this document are derived from
36 * software developed by the University of California, Berkeley, and its
37 * contributors.
38 */
39
40#pragma ident	"%Z%%M%	%I%	%E% SMI"
41
42/*
43 * rtime - get time from remote machine
44 *
45 * gets time, obtaining value from host
46 * on the udp/time socket.  Since timeserver returns
47 * with time of day in seconds since Jan 1, 1900,  must
48 * subtract seconds before Jan 1, 1970 to get
49 * what unix uses.
50 */
51
52#include <sys/types.h>
53#include <stdio.h>
54#include <string.h>
55#include <sys/socket.h>
56#include <sys/time.h>
57#include <errno.h>
58#include <netinet/in.h>
59#include <malloc.h>
60
61#define	NYEARS	(1970 - 1900)
62#define	TOFFSET ((uint_t)60*60*24*(365*NYEARS + (NYEARS/4)))
63
64extern int _socket(int, int, int);
65extern int _sendto(int, const char *, int, int,
66	const struct sockaddr *, int);
67extern int _recvfrom(int, char *, int, int,
68	struct sockaddr *, int *);
69extern int _connect(int, struct sockaddr *, int);
70extern int __rpc_dtbsize();
71extern ssize_t read(int, void *, size_t);
72extern int close(int);
73static void do_close();
74
75int
76rtime(addrp, timep, timeout)
77	struct sockaddr_in *addrp;
78	struct timeval *timep;
79	struct timeval *timeout;
80{
81	int s;
82	fd_set readfds;
83	int res;
84	uint_t thetime;
85	struct sockaddr_in from;
86	int fromlen;
87	int type;
88
89	if (timeout == NULL) {
90		type = SOCK_STREAM;
91	} else {
92		type = SOCK_DGRAM;
93	}
94	s = _socket(AF_INET, type, 0);
95	if (s < 0) {
96		return (-1);
97	}
98	addrp->sin_family = AF_INET;
99	addrp->sin_port = htons(IPPORT_TIMESERVER);
100	if (type == SOCK_DGRAM) {
101		res = _sendto(s, (char *)&thetime, sizeof (thetime), 0,
102		    (struct sockaddr *)addrp, sizeof (*addrp));
103		if (res < 0) {
104			do_close(s);
105			return (-1);
106		}
107		do {
108			FD_ZERO(&readfds);
109			FD_SET(s, &readfds);
110			res = select(__rpc_dtbsize(), &readfds, NULL,
111			    NULL, timeout);
112		} while (res < 0 && errno == EINTR);
113		if (res <= 0) {
114			if (res == 0) {
115				errno = ETIMEDOUT;
116			}
117			do_close(s);
118			return (-1);
119		}
120		fromlen = sizeof (from);
121		res = _recvfrom(s, (char *)&thetime, sizeof (thetime), 0,
122		    (struct sockaddr *)&from, &fromlen);
123		do_close(s);
124		if (res < 0) {
125			return (-1);
126		}
127	} else {
128		if (_connect(s, (struct sockaddr *)addrp,
129			sizeof (*addrp)) < 0) {
130			do_close(s);
131			return (-1);
132		}
133		res = read(s, (char *)&thetime, sizeof (thetime));
134		do_close(s);
135		if (res < 0) {
136			return (-1);
137		}
138	}
139	if (res != sizeof (thetime)) {
140		errno = EIO;
141		return (-1);
142	}
143	thetime = ntohl(thetime);
144
145	thetime = thetime - TOFFSET;
146#ifdef _ILP32
147	if (thetime > INT32_MAX)
148		thetime = INT32_MAX;
149#endif
150	timep->tv_sec = thetime;
151	timep->tv_usec = 0;
152	return (0);
153}
154
155static void
156do_close(s)
157	int s;
158{
159	int save;
160
161	save = errno;
162	(void) close(s);
163	errno = save;
164}
165