1 /* $OpenBSD: timeout.c,v 1.21 2022/07/02 19:00:35 kn 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 <ctype.h> 36 #include <err.h> 37 #include <errno.h> 38 #include <getopt.h> 39 #include <limits.h> 40 #include <signal.h> 41 #include <stdbool.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <unistd.h> 46 47 #define EXIT_TIMEOUT 124 48 49 static sig_atomic_t sig_chld = 0; 50 static sig_atomic_t sig_term = 0; 51 static sig_atomic_t sig_alrm = 0; 52 static sig_atomic_t sig_ign = 0; 53 54 static void __dead 55 usage(void) 56 { 57 fprintf(stderr, 58 "usage: timeout [-k time] [-s sig] [--foreground]" 59 " [--preserve-status] duration\n" 60 " command [args]\n"); 61 62 exit(1); 63 } 64 65 static double 66 parse_duration(const char *duration) 67 { 68 double ret; 69 char *suffix; 70 71 ret = strtod(duration, &suffix); 72 if (ret == 0 && suffix == duration) 73 errx(1, "duration is not a number"); 74 if (ret < 0 || ret >= 100000000UL) 75 errx(1, "duration out of range"); 76 77 if (suffix == NULL || *suffix == '\0') 78 return (ret); 79 80 if (suffix[1] != '\0') 81 errx(1, "duration unit suffix too long"); 82 83 switch (*suffix) { 84 case 's': 85 break; 86 case 'm': 87 ret *= 60; 88 break; 89 case 'h': 90 ret *= 60 * 60; 91 break; 92 case 'd': 93 ret *= 60 * 60 * 24; 94 break; 95 default: 96 errx(1, "duration unit suffix is invalid"); 97 } 98 99 return (ret); 100 } 101 102 static int 103 parse_signal(const char *str) 104 { 105 long long sig; 106 const char *errstr; 107 108 if (isalpha((unsigned char)*str)) { 109 int i; 110 111 if (strncasecmp(str, "SIG", 3) == 0) 112 str += 3; 113 for (i = 1; i < NSIG; i++) { 114 if (strcasecmp(str, sys_signame[i]) == 0) 115 return (i); 116 } 117 errx(1, "invalid signal name"); 118 } 119 120 sig = strtonum(str, 1, NSIG, &errstr); 121 if (errstr != NULL) 122 errx(1, "signal %s %s", str, errstr); 123 124 return (int)sig; 125 } 126 127 static void 128 sig_handler(int signo) 129 { 130 if (sig_ign != 0 && signo == sig_ign) { 131 sig_ign = 0; 132 return; 133 } 134 135 switch (signo) { 136 case SIGINT: 137 case SIGHUP: 138 case SIGQUIT: 139 case SIGTERM: 140 sig_term = signo; 141 break; 142 case SIGCHLD: 143 sig_chld = 1; 144 break; 145 case SIGALRM: 146 sig_alrm = 1; 147 break; 148 } 149 } 150 151 static void 152 set_interval(double iv) 153 { 154 struct itimerval tim; 155 156 memset(&tim, 0, sizeof(tim)); 157 tim.it_value.tv_sec = (time_t)iv; 158 iv -= (double)tim.it_value.tv_sec; 159 tim.it_value.tv_usec = (suseconds_t)(iv * 1000000UL); 160 161 if (setitimer(ITIMER_REAL, &tim, NULL) == -1) 162 err(1, "setitimer"); 163 } 164 165 int 166 main(int argc, char **argv) 167 { 168 int ch; 169 unsigned long i; 170 int foreground = 0, preserve = 0; 171 int pstat, status; 172 int killsig = SIGTERM; 173 pid_t pgid = 0, pid, cpid = 0; 174 double first_kill; 175 double second_kill = 0; 176 bool timedout = false; 177 bool do_second_kill = false; 178 struct sigaction signals; 179 int signums[] = {-1, SIGTERM, SIGINT, SIGHUP, SIGCHLD, 180 SIGALRM, SIGQUIT}; 181 182 const struct option longopts[] = { 183 { "preserve-status", no_argument, &preserve, 1 }, 184 { "foreground", no_argument, &foreground, 1 }, 185 { "kill-after", required_argument, NULL, 'k'}, 186 { "signal", required_argument, NULL, 's'}, 187 { "help", no_argument, NULL, 'h'}, 188 { NULL, 0, NULL, 0 } 189 }; 190 191 if (pledge("stdio proc exec", NULL) == -1) 192 err(1, "pledge"); 193 194 while ((ch = getopt_long(argc, argv, "+k:s:h", longopts, NULL)) != -1) { 195 switch (ch) { 196 case 'k': 197 do_second_kill = true; 198 second_kill = parse_duration(optarg); 199 break; 200 case 's': 201 killsig = parse_signal(optarg); 202 break; 203 case 0: 204 break; 205 default: 206 usage(); 207 break; 208 } 209 } 210 211 argc -= optind; 212 argv += optind; 213 214 if (argc < 2) 215 usage(); 216 217 first_kill = parse_duration(argv[0]); 218 argc--; 219 argv++; 220 221 if (!foreground) { 222 pgid = setpgid(0, 0); 223 224 if (pgid == -1) 225 err(1, "setpgid"); 226 } 227 228 memset(&signals, 0, sizeof(signals)); 229 sigemptyset(&signals.sa_mask); 230 231 if (killsig != SIGKILL && killsig != SIGSTOP) 232 signums[0] = killsig; 233 234 for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i++) 235 sigaddset(&signals.sa_mask, signums[i]); 236 237 signals.sa_handler = sig_handler; 238 signals.sa_flags = SA_RESTART; 239 240 for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i++) { 241 if (signums[i] != -1 && signums[i] != 0 && 242 sigaction(signums[i], &signals, NULL) == -1) 243 err(1, "sigaction"); 244 } 245 246 signal(SIGTTIN, SIG_IGN); 247 signal(SIGTTOU, SIG_IGN); 248 249 pid = fork(); 250 if (pid == -1) 251 err(1, "fork"); 252 else if (pid == 0) { 253 /* child process */ 254 signal(SIGTTIN, SIG_DFL); 255 signal(SIGTTOU, SIG_DFL); 256 257 execvp(argv[0], argv); 258 err(1, "%s", argv[0]); 259 } 260 261 /* parent continues here */ 262 263 if (pledge("stdio proc", NULL) == -1) 264 err(1, "pledge"); 265 266 if (sigprocmask(SIG_BLOCK, &signals.sa_mask, NULL) == -1) 267 err(1, "sigprocmask"); 268 269 set_interval(first_kill); 270 271 for (;;) { 272 sigemptyset(&signals.sa_mask); 273 sigsuspend(&signals.sa_mask); 274 275 if (sig_chld) { 276 sig_chld = 0; 277 while (((cpid = wait(&status)) < 0) && errno == EINTR) 278 continue; 279 280 if (cpid == pid) { 281 pstat = status; 282 break; 283 } 284 } else if (sig_alrm) { 285 sig_alrm = 0; 286 287 timedout = true; 288 if (!foreground) 289 killpg(pgid, killsig); 290 else 291 kill(pid, killsig); 292 293 if (do_second_kill) { 294 set_interval(second_kill); 295 second_kill = 0; 296 sig_ign = killsig; 297 killsig = SIGKILL; 298 } else 299 break; 300 301 } else if (sig_term) { 302 if (!foreground) 303 killpg(pgid, killsig); 304 else 305 kill(pid, (int)sig_term); 306 307 if (do_second_kill) { 308 set_interval(second_kill); 309 second_kill = 0; 310 sig_ign = killsig; 311 killsig = SIGKILL; 312 } else 313 break; 314 } 315 } 316 317 while (cpid != pid && wait(&pstat) == -1) { 318 if (errno != EINTR) 319 err(1, "wait"); 320 } 321 322 if (WEXITSTATUS(pstat)) 323 pstat = WEXITSTATUS(pstat); 324 else if (WIFSIGNALED(pstat)) 325 pstat = 128 + WTERMSIG(pstat); 326 327 if (timedout && !preserve) 328 pstat = EXIT_TIMEOUT; 329 330 return (pstat); 331 } 332