1 /*- 2 * Copyright (c) 2009, Sun Microsystems, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * - Redistributions of source code must retain the above copyright notice, 8 * this list of conditions and the following disclaimer. 9 * - Redistributions in binary form must reproduce the above copyright notice, 10 * this list of conditions and the following disclaimer in the documentation 11 * and/or other materials provided with the distribution. 12 * - Neither the name of Sun Microsystems, Inc. nor the names of its 13 * contributors may be used to endorse or promote products derived 14 * from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 * 28 * @(#)rtime.c 2.2 88/08/10 4.0 RPCSRC; from 1.8 88/02/08 SMI 29 * $FreeBSD: src/lib/libc/rpc/rtime.c,v 1.9 2005/03/10 00:57:01 stefanf Exp $ 30 * $DragonFly: src/lib/libc/rpc/rtime.c,v 1.5 2005/11/13 12:27:04 swildner Exp $ 31 */ 32 33 /* 34 * Copyright (c) 1988 by Sun Microsystems, Inc. 35 */ 36 37 /* 38 * rtime - get time from remote machine 39 * 40 * gets time, obtaining value from host 41 * on the udp/time socket. Since timeserver returns 42 * with time of day in seconds since Jan 1, 1900, must 43 * subtract seconds before Jan 1, 1970 to get 44 * what unix uses. 45 */ 46 #include "namespace.h" 47 #include <stdlib.h> 48 #include <string.h> 49 #include <unistd.h> 50 #include <errno.h> 51 #include <sys/types.h> 52 #include <sys/socket.h> 53 #include <sys/time.h> 54 #include <netinet/in.h> 55 #include <stdio.h> 56 #include <netdb.h> 57 #include "un-namespace.h" 58 59 extern int _rpc_dtablesize(void); 60 61 #define NYEARS (unsigned long)(1970 - 1900) 62 #define TOFFSET (unsigned long)(60*60*24*(365*NYEARS + (NYEARS/4))) 63 64 static void do_close(int); 65 66 int 67 rtime(struct sockaddr_in *addrp, struct timeval *timep, 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 NULL, 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 145 do_close(int s) 146 { 147 int save; 148 149 save = errno; 150 _close(s); 151 errno = save; 152 } 153