1 /* $OpenBSD: rdate.c,v 1.36 2021/11/15 15:14:24 millert Exp $ */ 2 /* $NetBSD: rdate.c,v 1.4 1996/03/16 12:37:45 pk Exp $ */ 3 4 /* 5 * Copyright (c) 1994 Christos Zoulas 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by Christos Zoulas. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 /* 35 * rdate.c: Set the date from the specified host 36 * 37 * Time is returned as the number of seconds since 38 * midnight January 1st 1900. 39 */ 40 41 #include <sys/socket.h> 42 #include <sys/time.h> 43 #include <sys/wait.h> 44 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <ctype.h> 48 #include <err.h> 49 #include <string.h> 50 #include <unistd.h> 51 #include <time.h> 52 53 /* there are systems without libutil; for portability */ 54 #ifndef NO_UTIL 55 #include <util.h> 56 #else 57 #define logwtmp(a,b,c) 58 #endif 59 60 void rfc868time_client(const char *, int, struct timeval *, struct timeval *, int); 61 void ntp_client(const char *, int, struct timeval *, struct timeval *, int); 62 63 extern char *__progname; 64 __dead void usage(void); 65 66 struct { 67 char message[2048]; 68 struct timeval new; 69 struct timeval adjust; 70 } pdata; 71 72 __dead void 73 usage(void) 74 { 75 (void) fprintf(stderr, "usage: %s [-46acnopsv] host\n", __progname); 76 exit(1); 77 } 78 79 int 80 main(int argc, char **argv) 81 { 82 int pr = 0, silent = 0, ntp = 1, verbose = 0; 83 int slidetime = 0, corrleaps = 0; 84 char *hname; 85 int c, p[2], pid; 86 int family = PF_UNSPEC; 87 88 while ((c = getopt(argc, argv, "46psanocv")) != -1) { 89 switch (c) { 90 case '4': 91 family = PF_INET; 92 break; 93 94 case '6': 95 family = PF_INET6; 96 break; 97 98 case 'p': 99 pr = 1; 100 break; 101 102 case 's': 103 silent = 1; 104 break; 105 106 case 'a': 107 slidetime = 1; 108 break; 109 110 case 'n': 111 ntp = 1; 112 break; 113 114 case 'o': 115 ntp = 0; 116 break; 117 118 case 'c': 119 corrleaps = 1; 120 break; 121 122 case 'v': 123 verbose = 1; 124 break; 125 126 default: 127 usage(); 128 } 129 } 130 if (argc - 1 != optind) 131 usage(); 132 hname = argv[optind]; 133 134 /* 135 * Privilege separation increases safety, with a slight reduction 136 * in precision because the time values have to return over a pipe. 137 */ 138 if (pipe(p) == -1) 139 err(1, "pipe"); 140 switch ((pid = fork())) { 141 case -1: 142 err(1, "fork"); 143 break; 144 case 0: 145 if (pledge("stdio inet dns", NULL) == -1) 146 err(1, "pledge"); 147 148 close(p[0]); /* read side of pipe */ 149 dup2(p[1], STDIN_FILENO); 150 if (p[1] != STDIN_FILENO) 151 close(p[1]); 152 dup2(STDIN_FILENO, STDOUT_FILENO); 153 dup2(STDOUT_FILENO, STDERR_FILENO); 154 setvbuf(stdout, NULL, _IOFBF, 0); 155 setvbuf(stderr, NULL, _IOFBF, 0); 156 157 if (ntp) 158 ntp_client(hname, family, &pdata.new, 159 &pdata.adjust, corrleaps); 160 else 161 rfc868time_client(hname, family, &pdata.new, 162 &pdata.adjust, corrleaps); 163 164 if (write(STDOUT_FILENO, &pdata, sizeof pdata) != sizeof pdata) 165 exit(1); 166 exit(0); 167 } 168 169 if (pledge("stdio rpath wpath settime", NULL) == -1) 170 err(1, "pledge"); 171 172 close(p[1]); /* write side of pipe */ 173 if (read(p[0], &pdata, sizeof pdata) < 1) 174 err(1, "child did not collect time"); 175 if (waitpid(pid, NULL, 0) == -1) 176 err(1, "waitpid"); 177 178 /* 179 * A viable timestamp from the child contains no message. 180 */ 181 if (pdata.message[0]) { 182 pdata.message[sizeof(pdata.message)- 1] = '\0'; 183 write(STDERR_FILENO, pdata.message, strlen(pdata.message)); 184 exit(1); 185 } 186 187 if (!pr) { 188 if (!slidetime) { 189 logwtmp("|", "date", ""); 190 if (settimeofday(&pdata.new, NULL) == -1) 191 err(1, "Could not set time of day"); 192 logwtmp("{", "date", ""); 193 } else { 194 if (adjtime(&pdata.adjust, NULL) == -1) 195 err(1, "Could not adjust time of day"); 196 } 197 } 198 199 if (pledge("stdio rpath", NULL) == -1) 200 err(1, "pledge"); 201 202 if (!silent) { 203 struct tm *ltm; 204 char buf[80]; 205 time_t tim = pdata.new.tv_sec; 206 double adjsec; 207 208 ltm = localtime(&tim); 209 (void) strftime(buf, sizeof buf, "%a %b %e %H:%M:%S %Z %Y\n", ltm); 210 (void) fputs(buf, stdout); 211 212 adjsec = pdata.adjust.tv_sec + pdata.adjust.tv_usec / 1.0e6; 213 214 if (slidetime || verbose) { 215 if (ntp) 216 (void) fprintf(stdout, 217 "%s: adjust local clock by %.6f seconds\n", 218 __progname, adjsec); 219 else 220 (void) fprintf(stdout, 221 "%s: adjust local clock by %lld seconds\n", 222 __progname, (long long)pdata.adjust.tv_sec); 223 } 224 } 225 226 return 0; 227 } 228