1 /* $NetBSD: misc.c,v 1.5 2017/08/17 08:53:00 christos Exp $ */ 2 3 /* Copyright 1988,1990,1993,1994 by Paul Vixie 4 * All rights reserved 5 */ 6 7 /* 8 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 9 * Copyright (c) 1997,2000 by Internet Software Consortium, Inc. 10 * 11 * Permission to use, copy, modify, and distribute this software for any 12 * purpose with or without fee is hereby granted, provided that the above 13 * copyright notice and this permission notice appear in all copies. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 16 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 17 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 18 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 19 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 20 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 21 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 22 */ 23 #include <sys/cdefs.h> 24 #if !defined(lint) && !defined(LINT) 25 #if 0 26 static char rcsid[] = "Id: misc.c,v 1.16 2004/01/23 18:56:43 vixie Exp"; 27 #else 28 __RCSID("$NetBSD: misc.c,v 1.5 2017/08/17 08:53:00 christos Exp $"); 29 #endif 30 #endif 31 32 /* vix 26jan87 [RCS has the rest of the log] 33 * vix 30dec86 [written] 34 */ 35 36 #include "cron.h" 37 #include <limits.h> 38 #include <vis.h> 39 40 #if defined(SYSLOG) && defined(LOG_FILE) 41 # undef LOG_FILE 42 #endif 43 44 #if defined(LOG_DAEMON) && !defined(LOG_CRON) 45 # define LOG_CRON LOG_DAEMON 46 #endif 47 48 #ifndef FACILITY 49 #define FACILITY LOG_CRON 50 #endif 51 52 static int LogFD = ERR; 53 54 #if defined(SYSLOG) 55 static int syslog_open = FALSE; 56 #endif 57 58 static void mkprint(char *, char *, size_t); 59 60 /* 61 * glue_strings is the overflow-safe equivalent of 62 * sprintf(buffer, "%s%c%s", a, separator, b); 63 * 64 * returns 1 on success, 0 on failure. 'buffer' MUST NOT be used if 65 * glue_strings fails. 66 */ 67 int 68 glue_strings(char *buffer, size_t buffer_size, const char *a, const char *b, 69 char separator) 70 { 71 char *buf; 72 char *buf_end; 73 74 if (buffer_size == 0) 75 return (0); 76 buf_end = buffer + buffer_size; 77 buf = buffer; 78 79 for ( /* nothing */; buf < buf_end && *a != '\0'; buf++, a++ ) 80 *buf = *a; 81 if (buf == buf_end) 82 return (0); 83 if (separator != '/' || buf == buffer || buf[-1] != '/') 84 *buf++ = separator; 85 if (buf == buf_end) 86 return (0); 87 for ( /* nothing */; buf < buf_end && *b != '\0'; buf++, b++ ) 88 *buf = *b; 89 if (buf == buf_end) 90 return (0); 91 *buf = '\0'; 92 return (1); 93 } 94 95 int 96 strcmp_until(const char *left, const char *right, char until) { 97 while (*left && *left != until && *left == *right) { 98 left++; 99 right++; 100 } 101 102 if ((*left=='\0' || *left == until) && 103 (*right=='\0' || *right == until)) { 104 return (0); 105 } 106 return (*left - *right); 107 } 108 109 #ifdef notdef 110 /* strdtb(s) - delete trailing blanks in string 's' and return new length 111 */ 112 int 113 strdtb(char *s) { 114 char *x = s; 115 116 /* scan forward to the null 117 */ 118 while (*x) 119 x++; 120 121 /* scan backward to either the first character before the string, 122 * or the last non-blank in the string, whichever comes first. 123 */ 124 do {x--;} 125 while (x >= s && isspace((unsigned char)*x)); 126 127 /* one character beyond where we stopped above is where the null 128 * goes. 129 */ 130 *++x = '\0'; 131 132 /* the difference between the position of the null character and 133 * the position of the first character of the string is the length. 134 */ 135 return (int)(x - s); 136 } 137 #endif 138 139 int 140 set_debug_flags(const char *flags) { 141 /* debug flags are of the form flag[,flag ...] 142 * 143 * if an error occurs, print a message to stdout and return FALSE. 144 * otherwise return TRUE after setting ERROR_FLAGS. 145 */ 146 147 #if !DEBUGGING 148 149 printf("this program was compiled without debugging enabled\n"); 150 return (FALSE); 151 152 #else /* DEBUGGING */ 153 154 const char *pc = flags; 155 156 DebugFlags = 0; 157 158 while (*pc) { 159 const char * const *test; 160 int mask; 161 162 /* try to find debug flag name in our list. 163 */ 164 for (test = DebugFlagNames, mask = 1; 165 *test != NULL && strcmp_until(*test, pc, ','); 166 test++, mask <<= 1) 167 continue; 168 169 if (!*test) { 170 warnx("unrecognized debug flag <%s> <%s>\n", flags, pc); 171 return (FALSE); 172 } 173 174 DebugFlags |= mask; 175 176 /* skip to the next flag 177 */ 178 while (*pc && *pc != ',') 179 pc++; 180 if (*pc == ',') 181 pc++; 182 } 183 184 if (DebugFlags) { 185 int flag; 186 187 (void)fprintf(stderr, "debug flags enabled:"); 188 189 for (flag = 0; DebugFlagNames[flag]; flag++) 190 if (DebugFlags & (1 << flag)) 191 (void)fprintf(stderr, " %s", DebugFlagNames[flag]); 192 (void)fprintf(stderr, "\n"); 193 } 194 195 return (TRUE); 196 197 #endif /* DEBUGGING */ 198 } 199 200 void 201 set_cron_uid(void) { 202 #if defined(BSD) || defined(POSIX) 203 if (seteuid(ROOT_UID) < OK) { 204 err(ERROR_EXIT, "cannot seteuid"); 205 } 206 #else 207 if (setuid(ROOT_UID) < OK) { 208 err(ERROR_EXIT, "cannot setuid"); 209 } 210 #endif 211 } 212 213 void 214 set_cron_cwd(void) { 215 struct stat sb; 216 struct group *grp = NULL; 217 218 #ifdef CRON_GROUP 219 grp = getgrnam(CRON_GROUP); 220 #endif 221 /* first check for CRONDIR ("/var/cron" or some such) 222 */ 223 #ifdef ENABLE_FIX_DIRECTORIES 224 if (stat(CRONDIR, &sb) < OK && errno == ENOENT) { 225 warn("Cannot stat `%s'", CRONDIR); 226 if (OK == mkdir(CRONDIR, 0710)) { 227 (void)fprintf(stderr, "%s: created\n", CRONDIR); 228 if (stat(CRONDIR, &sb) == -1) 229 err(ERROR_EXIT, "cannot stat `%s'", CRONDIR); 230 } else { 231 err(ERROR_EXIT, "cannot create `%s'", CRONDIR); 232 } 233 } 234 if (!S_ISDIR(sb.st_mode)) { 235 errx(ERROR_EXIT, "`%s' is not a directory, bailing out.", 236 CRONDIR); 237 } 238 #endif /* ENABLE_FIX_DIRECTORIES */ 239 if (chdir(CRONDIR) < OK) { 240 err(ERROR_EXIT, "cannot chdir `%s', bailing out.\n", CRONDIR); 241 } 242 243 /* CRONDIR okay (now==CWD), now look at SPOOL_DIR ("tabs" or some such) 244 */ 245 #ifdef ENABLE_FIX_DIRECTORIES 246 if (stat(SPOOL_DIR, &sb) < OK && errno == ENOENT) { 247 warn("cannot stat `%s'", SPOOL_DIR); 248 if (OK == mkdir(SPOOL_DIR, 0700)) { 249 (void)fprintf(stderr, "%s: created\n", SPOOL_DIR); 250 if (stat(SPOOL_DIR, &sb) == -1) 251 err(ERROR_EXIT, "cannot stat `%s'", CRONDIR); 252 } else { 253 err(ERROR_EXIT, "cannot create `%s'", SPOOL_DIR); 254 } 255 } 256 #else 257 if (stat(SPOOL_DIR, &sb)) { 258 err(ERROR_EXIT, "cannot stat `%s'", SPOOL_DIR); 259 } 260 #endif /* ENABLE_FIX_DIRECTORIES */ 261 if (!S_ISDIR(sb.st_mode)) { 262 errx(ERROR_EXIT, "`%s' is not a directory, bailing out.", 263 SPOOL_DIR); 264 } 265 if (grp != NULL) { 266 if (sb.st_gid != grp->gr_gid) { 267 #ifdef ENABLE_FIX_DIRECTORIES 268 errx(ERROR_EXIT, "Bad group %d != %d for `%s'", 269 (int)sb.st_gid, (int)grp->gr_gid, SPOOL_DIR); 270 #else 271 if (chown(SPOOL_DIR, (uid_t)-1, grp->gr_gid) == -1) 272 err(ERROR_EXIT, "cannot chown `%s'", SPOOL_DIR); 273 #endif 274 } 275 if (sb.st_mode != 01730) 276 #ifdef ENABLE_FIX_DIRECTORIES 277 errx(ERROR_EXIT, "Bad mode %#o != %#o for `%s'", 278 (int)sb.st_mode, 01730, SPOOL_DIR); 279 #else 280 if (chmod(SPOOL_DIR, 01730) == -1) 281 err(ERROR_EXIT, "cannot chmod `%s'", SPOOL_DIR); 282 #endif 283 } 284 } 285 286 /* acquire_daemonlock() - write our PID into /etc/cron.pid, unless 287 * another daemon is already running, which we detect here. 288 * 289 * note: main() calls us twice; once before forking, once after. 290 * we maintain static storage of the file pointer so that we 291 * can rewrite our PID into _PATH_CRON_PID after the fork. 292 */ 293 void 294 acquire_daemonlock(int closeflag) { 295 static int fd = -1; 296 char buf[3*MAX_FNAME]; 297 const char *pidfile; 298 char *ep; 299 long otherpid; 300 ssize_t num; 301 302 if (closeflag) { 303 /* close stashed fd for child so we don't leak it. */ 304 if (fd != -1) { 305 (void)close(fd); 306 fd = -1; 307 } 308 return; 309 } 310 311 if (fd == -1) { 312 pidfile = _PATH_CRON_PID; 313 /* Initial mode is 0600 to prevent flock() race/DoS. */ 314 if ((fd = open(pidfile, O_RDWR|O_CREAT, 0600)) == -1) { 315 log_itx("CRON", getpid(), "DEATH", 316 "can't open or create %s: %s", 317 pidfile, strerror(errno)); 318 exit(ERROR_EXIT); 319 } 320 /* fd must be > STDERR since we dup fd 0-2 to /dev/null */ 321 if (fd <= STDERR) { 322 if (dup2(fd, STDERR + 1) < 0) { 323 log_itx("CRON", getpid(), "DEATH", 324 "can't dup pid fd: %s", strerror(errno)); 325 exit(ERROR_EXIT); 326 } 327 close(fd); 328 fd = STDERR + 1; 329 } 330 331 if (flock(fd, LOCK_EX|LOCK_NB) < OK) { 332 int save_errno = errno; 333 334 memset(buf, 0, sizeof(buf)); 335 if ((num = read(fd, buf, sizeof(buf) - 1)) > 0 && 336 (otherpid = strtol(buf, &ep, 10)) > 0 && 337 ep != buf && *ep == '\n' && otherpid != LONG_MAX) { 338 log_itx("CRON", getpid(), "DEATH", 339 "can't lock %s, otherpid may be %ld: %s", 340 pidfile, otherpid, strerror(save_errno)); 341 } else { 342 log_itx("CRON", getpid(), "DEATH", 343 "can't lock %s, otherpid unknown: %s", 344 pidfile, strerror(save_errno)); 345 } 346 exit(ERROR_EXIT); 347 } 348 (void) fchmod(fd, 0644); 349 (void) fcntl(fd, F_SETFD, 1); 350 } 351 352 (void)snprintf(buf, sizeof(buf), "%ld\n", (long)getpid()); 353 (void) lseek(fd, (off_t)0, SEEK_SET); 354 num = write(fd, buf, strlen(buf)); 355 (void) ftruncate(fd, num); 356 357 /* abandon fd even though the file is open. we need to keep 358 * it open and locked, but we don't need the handles elsewhere. 359 */ 360 } 361 362 /* get_char(file) : like getc() but increment LineNumber on newlines 363 */ 364 int 365 get_char(FILE *file) { 366 int ch; 367 368 ch = getc(file); 369 if (ch == '\n') 370 Set_LineNum(LineNumber + 1); 371 return (ch); 372 } 373 374 /* unget_char(ch, file) : like ungetc but do LineNumber processing 375 */ 376 void 377 unget_char(int ch, FILE *file) { 378 (void)ungetc(ch, file); 379 if (ch == '\n') 380 Set_LineNum(LineNumber - 1); 381 } 382 383 /* get_string(str, max, file, termstr) : like fgets() but 384 * (1) has terminator string which should include \n 385 * (2) will always leave room for the null 386 * (3) uses get_char() so LineNumber will be accurate 387 * (4) returns EOF or terminating character, whichever 388 */ 389 int 390 get_string(char *string, int size, FILE *file, const char *terms) { 391 int ch; 392 393 while (EOF != (ch = get_char(file)) && !strchr(terms, ch)) { 394 if (size > 1) { 395 *string++ = (char) ch; 396 size--; 397 } 398 } 399 400 if (size > 0) 401 *string = '\0'; 402 403 return (ch); 404 } 405 406 /* skip_comments(file) : read past comment (if any) 407 */ 408 void 409 skip_comments(FILE *file) { 410 int ch; 411 412 while (EOF != (ch = get_char(file))) { 413 /* ch is now the first character of a line. 414 */ 415 416 while (ch == ' ' || ch == '\t') 417 ch = get_char(file); 418 419 if (ch == EOF) 420 break; 421 422 /* ch is now the first non-blank character of a line. 423 */ 424 425 if (ch != '\n' && ch != '#') 426 break; 427 428 /* ch must be a newline or comment as first non-blank 429 * character on a line. 430 */ 431 432 while (ch != '\n' && ch != EOF) 433 ch = get_char(file); 434 435 /* ch is now the newline of a line which we're going to 436 * ignore. 437 */ 438 } 439 if (ch != EOF) 440 unget_char(ch, file); 441 } 442 443 void 444 log_itx(const char *username, PID_T xpid, const char *event, const char *fmt, 445 ...) 446 { 447 char *detail; 448 va_list ap; 449 va_start(ap, fmt); 450 if (vasprintf(&detail, fmt, ap) == -1) { 451 va_end(ap); 452 return; 453 } 454 log_it(username, xpid, event, detail); 455 free(detail); 456 } 457 458 void 459 log_it(const char *username, PID_T xpid, const char *event, const char *detail) { 460 #if defined(LOG_FILE) || DEBUGGING 461 PID_T pid = xpid; 462 #endif 463 #if defined(LOG_FILE) 464 char *msg; 465 int msglen; 466 TIME_T now = time((TIME_T) 0); 467 struct tm *t = localtime(&now); 468 469 if (LogFD < OK) { 470 LogFD = open(LOG_FILE, O_WRONLY|O_APPEND|O_CREAT, 0600); 471 if (LogFD < OK) { 472 warn("can't open log file `%s'", LOG_FILE); 473 } else { 474 (void) fcntl(LogFD, F_SETFD, FD_CLOEXEC); 475 } 476 } 477 478 /* we have to sprintf() it because fprintf() doesn't always write 479 * everything out in one chunk and this has to be atomically appended 480 * to the log file. 481 */ 482 msglen = asprintf(&msg, 483 "%s (%02d/%02d-%02d:%02d:%02d-%d) %s (%s)\n", username, 484 t->tm_mon + 1, t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec, pid, 485 event, detail); 486 if (msglen == -1) 487 return; 488 489 if (LogFD < OK || write(LogFD, msg, (size_t)msglen) < OK) { 490 warn("can't write to log file"); 491 write(STDERR, msg, (size_t)msglen); 492 } 493 494 free(msg); 495 #endif /*LOG_FILE*/ 496 497 #if defined(SYSLOG) 498 if (!syslog_open) { 499 # ifdef LOG_DAEMON 500 openlog(getprogname(), LOG_PID, FACILITY); 501 # else 502 openlog(getprogname(), LOG_PID); 503 # endif 504 syslog_open = TRUE; /* assume openlog success */ 505 } 506 507 syslog(LOG_INFO, "(%s) %s (%s)", username, event, detail); 508 509 #endif /*SYSLOG*/ 510 511 #if DEBUGGING 512 if (DebugFlags) { 513 (void)fprintf(stderr, "log_it: (%s %ld) %s (%s)\n", 514 username, (long)pid, event, detail); 515 } 516 #endif 517 } 518 519 void 520 log_close(void) { 521 if (LogFD != ERR) { 522 (void)close(LogFD); 523 LogFD = ERR; 524 } 525 #if defined(SYSLOG) 526 closelog(); 527 syslog_open = FALSE; 528 #endif /*SYSLOG*/ 529 } 530 531 /* warning: 532 * heavily ascii-dependent. 533 */ 534 static void 535 mkprint(char *dst, char *src, size_t len) 536 { 537 while(len > 0 && isblank((unsigned char) *src)) 538 len--, src++; 539 540 (void)strvisx(dst, src, len, VIS_TAB|VIS_NL); 541 } 542 543 /* warning: 544 * returns a pointer to malloc'd storage, you must call free yourself. 545 */ 546 char * 547 mkprints(char *src, size_t len) 548 { 549 char *dst = malloc(len*4 + 1); 550 551 if (dst) 552 mkprint(dst, src, len); 553 554 return (dst); 555 } 556 557 #ifdef MAIL_DATE 558 /* Sat, 27 Feb 1993 11:44:51 -0800 (CST) 559 * 1234567890123456789012345678901234567 560 */ 561 char * 562 arpadate(time_t *clock) 563 { 564 time_t t = clock ? *clock : time((TIME_T) 0); 565 struct tm tm = *localtime(&t); 566 long gmtoff = get_gmtoff(&t, &tm); 567 int hours = gmtoff / SECONDS_PER_HOUR; 568 int minutes = (gmtoff - (hours * SECONDS_PER_HOUR)) / SECONDS_PER_MINUTE; 569 static char ret[64]; /* zone name might be >3 chars */ 570 571 if (minutes < 0) 572 minutes = -minutes; 573 574 (void)strftime(ret, sizeof(ret), "%a, %e %b %Y %T ????? (%Z)", &tm); 575 (void)snprintf(strchr(ret, '?'), "% .2d%.2d", hours, minutes); 576 ret[sizeof(ret) - 1] = '\0'; 577 return ret; 578 } 579 #endif /*MAIL_DATE*/ 580 581 size_t 582 strlens(const char *last, ...) { 583 va_list ap; 584 size_t ret = 0; 585 const char *str; 586 587 va_start(ap, last); 588 for (str = last; str != NULL; str = va_arg(ap, const char *)) 589 ret += strlen(str); 590 va_end(ap); 591 return (ret); 592 } 593 594 /* Return the offset from GMT in seconds (algorithm taken from sendmail). 595 * 596 * warning: 597 * clobbers the static storage space used by localtime() and gmtime(). 598 * If the local pointer is non-NULL it *must* point to a local copy. 599 */ 600 #ifndef HAVE_TM_GMTOFF 601 long get_gmtoff(time_t *clock, struct tm *local) 602 { 603 struct tm gmt; 604 long offset; 605 606 gmt = *gmtime(clock); 607 if (local == NULL) 608 local = localtime(clock); 609 610 offset = (local->tm_sec - gmt.tm_sec) + 611 ((local->tm_min - gmt.tm_min) * 60) + 612 ((local->tm_hour - gmt.tm_hour) * 3600); 613 614 /* Timezone may cause year rollover to happen on a different day. */ 615 if (local->tm_year < gmt.tm_year) 616 offset -= 24 * 3600; 617 else if (local->tm_year > gmt.tm_year) 618 offset -= 24 * 3600; 619 else if (local->tm_yday < gmt.tm_yday) 620 offset -= 24 * 3600; 621 else if (local->tm_yday > gmt.tm_yday) 622 offset += 24 * 3600; 623 624 return (offset); 625 } 626 #endif /* HAVE_TM_GMTOFF */ 627
Indexes created Tue Feb 24 01:34:59 UTC 2026