1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2009, Sun Microsystems, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 * - Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 * - Neither the name of Sun Microsystems, Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 /*
32 * Copyright (c) 1988 by Sun Microsystems, Inc.
33
34 */
35
36 /*
37 * rtime - get time from remote machine
38 *
39 * gets time, obtaining value from host
40 * on the udp/time socket. Since timeserver returns
41 * with time of day in seconds since Jan 1, 1900, must
42 * subtract seconds before Jan 1, 1970 to get
43 * what unix uses.
44 */
45 #include "namespace.h"
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <errno.h>
50 #include <sys/types.h>
51 #include <sys/socket.h>
52 #include <sys/time.h>
53 #include <netinet/in.h>
54 #include <stdio.h>
55 #include <netdb.h>
56 #include "un-namespace.h"
57
58 extern int _rpc_dtablesize( void );
59
60 #define NYEARS (unsigned long)(1970 - 1900)
61 #define TOFFSET (unsigned long)(60*60*24*(365*NYEARS + (NYEARS/4)))
62
63 static void do_close( int );
64
65 int
rtime(struct sockaddr_in * addrp,struct timeval * timep,struct timeval * timeout)66 rtime(struct sockaddr_in *addrp, struct timeval *timep,
67 struct timeval *timeout)
68 {
69 int s;
70 fd_set readfds;
71 int res;
72 unsigned long thetime;
73 struct sockaddr_in from;
74 socklen_t fromlen;
75 int type;
76 struct servent *serv;
77
78 if (timeout == NULL) {
79 type = SOCK_STREAM;
80 } else {
81 type = SOCK_DGRAM;
82 }
83 s = _socket(AF_INET, type, 0);
84 if (s < 0) {
85 return(-1);
86 }
87 addrp->sin_family = AF_INET;
88
89 /* TCP and UDP port are the same in this case */
90 if ((serv = getservbyname("time", "tcp")) == NULL) {
91 return(-1);
92 }
93
94 addrp->sin_port = serv->s_port;
95
96 if (type == SOCK_DGRAM) {
97 res = _sendto(s, (char *)&thetime, sizeof(thetime), 0,
98 (struct sockaddr *)addrp, sizeof(*addrp));
99 if (res < 0) {
100 do_close(s);
101 return(-1);
102 }
103 do {
104 FD_ZERO(&readfds);
105 FD_SET(s, &readfds);
106 res = _select(_rpc_dtablesize(), &readfds,
107 (fd_set *)NULL, (fd_set *)NULL, timeout);
108 } while (res < 0 && errno == EINTR);
109 if (res <= 0) {
110 if (res == 0) {
111 errno = ETIMEDOUT;
112 }
113 do_close(s);
114 return(-1);
115 }
116 fromlen = sizeof(from);
117 res = _recvfrom(s, (char *)&thetime, sizeof(thetime), 0,
118 (struct sockaddr *)&from, &fromlen);
119 do_close(s);
120 if (res < 0) {
121 return(-1);
122 }
123 } else {
124 if (_connect(s, (struct sockaddr *)addrp, sizeof(*addrp)) < 0) {
125 do_close(s);
126 return(-1);
127 }
128 res = _read(s, (char *)&thetime, sizeof(thetime));
129 do_close(s);
130 if (res < 0) {
131 return(-1);
132 }
133 }
134 if (res != sizeof(thetime)) {
135 errno = EIO;
136 return(-1);
137 }
138 thetime = ntohl(thetime);
139 timep->tv_sec = thetime - TOFFSET;
140 timep->tv_usec = 0;
141 return(0);
142 }
143
144 static void
do_close(int s)145 do_close(int s)
146 {
147 int save;
148
149 save = errno;
150 (void)_close(s);
151 errno = save;
152 }
153