1 /* $OpenBSD: timeout.c,v 1.19 2021/09/04 11:49:11 schwarze Exp $ */ 2 3 /* 4 * Copyright (c) 2021 Job Snijders <job@openbsd.org> 5 * Copyright (c) 2014 Baptiste Daroussin <bapt@FreeBSD.org> 6 * Copyright (c) 2014 Vsevolod Stakhov <vsevolod@FreeBSD.org> 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 * in this position and unchanged. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/types.h> 32 #include <sys/time.h> 33 #include <sys/wait.h> 34 35 #include <err.h> 36 #include <errno.h> 37 #include <getopt.h> 38 #include <limits.h> 39 #include <signal.h> 40 #include <stdbool.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <unistd.h> 45 46 #define EXIT_TIMEOUT 124 47 48 static sig_atomic_t sig_chld = 0; 49 static sig_atomic_t sig_term = 0; 50 static sig_atomic_t sig_alrm = 0; 51 static sig_atomic_t sig_ign = 0; 52 53 static void __dead 54 usage(void) 55 { 56 fprintf(stderr, 57 "usage: timeout [-k time] [-s sig] [--foreground]" 58 " [--preserve-status] duration\n" 59 " command [args]\n"); 60 61 exit(1); 62 } 63 64 static double 65 parse_duration(const char *duration) 66 { 67 double ret; 68 char *suffix; 69 70 ret = strtod(duration, &suffix); 71 if (ret == 0 && suffix == duration) 72 errx(1, "duration is not a number"); 73 if (ret < 0 || ret >= 100000000UL) 74 errx(1, "duration out of range"); 75 76 if (suffix == NULL || *suffix == '\0') 77 return (ret); 78 79 if (suffix[1] != '\0') 80 errx(1, "duration unit suffix too long"); 81 82 switch (*suffix) { 83 case 's': 84 break; 85 case 'm': 86 ret *= 60; 87 break; 88 case 'h': 89 ret *= 60 * 60; 90 break; 91 case 'd': 92 ret *= 60 * 60 * 24; 93 break; 94 default: 95 errx(1, "duration unit suffix is invalid"); 96 } 97 98 return (ret); 99 } 100 101 static int 102 parse_signal(const char *str) 103 { 104 long long sig; 105 const char *errstr; 106 107 if (strncasecmp(str, "SIG", 3) == 0) { 108 int i; 109 110 str += 3; 111 for (i = 1; i < NSIG; i++) { 112 if (strcasecmp(str, sys_signame[i]) == 0) 113 return (i); 114 } 115 errx(1, "invalid signal name"); 116 } 117 118 sig = strtonum(str, 1, NSIG, &errstr); 119 if (errstr != NULL) 120 errx(1, "signal %s %s", str, errstr); 121 122 return (int)sig; 123 } 124 125 static void 126 sig_handler(int signo) 127 { 128 if (sig_ign != 0 && signo == sig_ign) { 129 sig_ign = 0; 130 return; 131 } 132 133 switch (signo) { 134 case SIGINT: 135 case SIGHUP: 136 case SIGQUIT: 137 case SIGTERM: 138 sig_term = signo; 139 break; 140 case SIGCHLD: 141 sig_chld = 1; 142 break; 143 case SIGALRM: 144 sig_alrm = 1; 145 break; 146 } 147 } 148 149 static void 150 set_interval(double iv) 151 { 152 struct itimerval tim; 153 154 memset(&tim, 0, sizeof(tim)); 155 tim.it_value.tv_sec = (time_t)iv; 156 iv -= (double)tim.it_value.tv_sec; 157 tim.it_value.tv_usec = (suseconds_t)(iv * 1000000UL); 158 159 if (setitimer(ITIMER_REAL, &tim, NULL) == -1) 160 err(1, "setitimer"); 161 } 162 163 int 164 main(int argc, char **argv) 165 { 166 int ch; 167 unsigned long i; 168 int foreground = 0, preserve = 0; 169 int pstat, status; 170 int killsig = SIGTERM; 171 pid_t pgid = 0, pid, cpid = 0; 172 double first_kill; 173 double second_kill = 0; 174 bool timedout = false; 175 bool do_second_kill = false; 176 struct sigaction signals; 177 int signums[] = {-1, SIGTERM, SIGINT, SIGHUP, SIGCHLD, 178 SIGALRM, SIGQUIT}; 179 180 const struct option longopts[] = { 181 { "preserve-status", no_argument, &preserve, 1 }, 182 { "foreground", no_argument, &foreground, 1 }, 183 { "kill-after", required_argument, NULL, 'k'}, 184 { "signal", required_argument, NULL, 's'}, 185 { "help", no_argument, NULL, 'h'}, 186 { NULL, 0, NULL, 0 } 187 }; 188 189 if (pledge("stdio proc exec", NULL) == -1) 190 err(1, "pledge"); 191 192 while ((ch = getopt_long(argc, argv, "+k:s:h", longopts, NULL)) != -1) { 193 switch (ch) { 194 case 'k': 195 do_second_kill = true; 196 second_kill = parse_duration(optarg); 197 break; 198 case 's': 199 killsig = parse_signal(optarg); 200 break; 201 case 0: 202 break; 203 default: 204 usage(); 205 break; 206 } 207 } 208 209 argc -= optind; 210 argv += optind; 211 212 if (argc < 2) 213 usage(); 214 215 first_kill = parse_duration(argv[0]); 216 argc--; 217 argv++; 218 219 if (!foreground) { 220 pgid = setpgid(0, 0); 221 222 if (pgid == -1) 223 err(1, "setpgid"); 224 } 225 226 memset(&signals, 0, sizeof(signals)); 227 sigemptyset(&signals.sa_mask); 228 229 if (killsig != SIGKILL && killsig != SIGSTOP) 230 signums[0] = killsig; 231 232 for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i++) 233 sigaddset(&signals.sa_mask, signums[i]); 234 235 signals.sa_handler = sig_handler; 236 signals.sa_flags = SA_RESTART; 237 238 for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i++) { 239 if (signums[i] != -1 && signums[i] != 0 && 240 sigaction(signums[i], &signals, NULL) == -1) 241 err(1, "sigaction"); 242 } 243 244 signal(SIGTTIN, SIG_IGN); 245 signal(SIGTTOU, SIG_IGN); 246 247 pid = fork(); 248 if (pid == -1) 249 err(1, "fork"); 250 else if (pid == 0) { 251 /* child process */ 252 signal(SIGTTIN, SIG_DFL); 253 signal(SIGTTOU, SIG_DFL); 254 255 execvp(argv[0], argv); 256 err(1, "%s", argv[0]); 257 } 258 259 /* parent continues here */ 260 261 if (pledge("stdio proc", NULL) == -1) 262 err(1, "pledge"); 263 264 if (sigprocmask(SIG_BLOCK, &signals.sa_mask, NULL) == -1) 265 err(1, "sigprocmask"); 266 267 set_interval(first_kill); 268 269 for (;;) { 270 sigemptyset(&signals.sa_mask); 271 sigsuspend(&signals.sa_mask); 272 273 if (sig_chld) { 274 sig_chld = 0; 275 while (((cpid = wait(&status)) < 0) && errno == EINTR) 276 continue; 277 278 if (cpid == pid) { 279 pstat = status; 280 break; 281 } 282 } else if (sig_alrm) { 283 sig_alrm = 0; 284 285 timedout = true; 286 if (!foreground) 287 killpg(pgid, killsig); 288 else 289 kill(pid, killsig); 290 291 if (do_second_kill) { 292 set_interval(second_kill); 293 second_kill = 0; 294 sig_ign = killsig; 295 killsig = SIGKILL; 296 } else 297 break; 298 299 } else if (sig_term) { 300 if (!foreground) 301 killpg(pgid, killsig); 302 else 303 kill(pid, (int)sig_term); 304 305 if (do_second_kill) { 306 set_interval(second_kill); 307 second_kill = 0; 308 sig_ign = killsig; 309 killsig = SIGKILL; 310 } else 311 break; 312 } 313 } 314 315 while (cpid != pid && wait(&pstat) == -1) { 316 if (errno != EINTR) 317 err(1, "wait"); 318 } 319 320 if (WEXITSTATUS(pstat)) 321 pstat = WEXITSTATUS(pstat); 322 else if (WIFSIGNALED(pstat)) 323 pstat = 128 + WTERMSIG(pstat); 324 325 if (timedout && !preserve) 326 pstat = EXIT_TIMEOUT; 327 328 return (pstat); 329 } 330