crontab(8)/mtrace(8): Remove CVS ID handling.
[dragonfly.git] / usr.sbin / cron / crontab / crontab.c
CommitLineData
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1/* Copyright 1988,1990,1993,1994 by Paul Vixie
2 * All rights reserved
3 *
4 * Distribute freely, except: don't remove my name from the source or
5 * documentation (don't take credit for my work), mark your changes (don't
6 * get me blamed for your possible bugs), don't alter or remove this
7 * notice. May be sold if buildable source is provided to buyer. No
8 * warrantee of any kind, express or implied, is included with this
9 * software; use at your own risk, responsibility for damages (if any) to
10 * anyone resulting from the use of this software rests entirely with the
11 * user.
12 *
13 * Send bug reports, bug fixes, enhancements, requests, flames, etc., and
14 * I'll try to keep a version up to date. I can be reached as follows:
15 * Paul Vixie <paul@vix.com> uunet!decwrl!vixie!paul
1de703da 16 *
984263bc 17 * From Id: crontab.c,v 2.13 1994/01/17 03:20:37 vixie Exp
1de703da 18 * $FreeBSD: src/usr.sbin/cron/crontab/crontab.c,v 1.12.2.4 2001/06/16 03:18:37 peter Exp $
71126e33 19 * $DragonFly: src/usr.sbin/cron/crontab/crontab.c,v 1.5 2004/12/18 22:48:03 swildner Exp $
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20 */
21
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22/* crontab - install and manage per-user crontab files
23 * vix 02may87 [RCS has the rest of the log]
24 * vix 26jan87 [original]
25 */
26
27#define MAIN_PROGRAM
28
29#include "cron.h"
30#include <errno.h>
31#include <fcntl.h>
32#include <paths.h>
33#include <sys/file.h>
34#include <sys/stat.h>
35#ifdef USE_UTIMES
36# include <sys/time.h>
37#else
38# include <time.h>
39# include <utime.h>
40#endif
41#if defined(POSIX)
42# include <locale.h>
43#endif
44
45
46#define NHEADER_LINES 3
47
48
49enum opt_t { opt_unknown, opt_list, opt_delete, opt_edit, opt_replace };
50
51#if DEBUGGING
52static char *Options[] = { "???", "list", "delete", "edit", "replace" };
53#endif
54
55
56static PID_T Pid;
57static char User[MAX_UNAME], RealUser[MAX_UNAME];
58static char Filename[MAX_FNAME];
59static FILE *NewCrontab;
60static int CheckErrorCount;
61static enum opt_t Option;
62static struct passwd *pw;
2d8a3be7
EN
63static void list_cmd(void),
64 delete_cmd(void),
65 edit_cmd(void),
66 poke_daemon(void),
67 check_error(char *),
68 parse_args(int c, char *v[]);
69static int replace_cmd(void);
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70
71
72static void
3a2e6dbb 73usage(char *msg)
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MD
74{
75 fprintf(stderr, "crontab: usage error: %s\n", msg);
76 fprintf(stderr, "%s\n%s\n",
77 "usage: crontab [-u user] file",
78 " crontab [-u user] { -e | -l | -r }");
79 exit(ERROR_EXIT);
80}
81
82
83int
3a2e6dbb 84main(int argc, char **argv)
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MD
85{
86 int exitstatus;
87
88 Pid = getpid();
89 ProgramName = argv[0];
90
91#if defined(POSIX)
92 setlocale(LC_ALL, "");
93#endif
94
95#if defined(BSD)
96 setlinebuf(stderr);
97#endif
98 parse_args(argc, argv); /* sets many globals, opens a file */
99 set_cron_uid();
100 set_cron_cwd();
101 if (!allowed(User)) {
102 warnx("you (%s) are not allowed to use this program", User);
103 log_it(RealUser, Pid, "AUTH", "crontab command not allowed");
104 exit(ERROR_EXIT);
105 }
106 exitstatus = OK_EXIT;
107 switch (Option) {
108 case opt_list: list_cmd();
109 break;
110 case opt_delete: delete_cmd();
111 break;
112 case opt_edit: edit_cmd();
113 break;
114 case opt_replace: if (replace_cmd() < 0)
115 exitstatus = ERROR_EXIT;
116 break;
117 case opt_unknown:
118 break;
119 }
120 exit(0);
121 /*NOTREACHED*/
122}
123
124
125static void
3a2e6dbb 126parse_args(int argc, char **argv)
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MD
127{
128 int argch;
129
130 if (!(pw = getpwuid(getuid())))
131 errx(ERROR_EXIT, "your UID isn't in the passwd file, bailing out");
71126e33 132 strncpy(User, pw->pw_name, (sizeof User)-1);
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133 User[(sizeof User)-1] = '\0';
134 strcpy(RealUser, User);
135 Filename[0] = '\0';
136 Option = opt_unknown;
137 while ((argch = getopt(argc, argv, "u:lerx:")) != -1) {
138 switch (argch) {
139 case 'x':
140 if (!set_debug_flags(optarg))
141 usage("bad debug option");
142 break;
143 case 'u':
144 if (getuid() != ROOT_UID)
145 errx(ERROR_EXIT, "must be privileged to use -u");
146 if (!(pw = getpwnam(optarg)))
147 errx(ERROR_EXIT, "user `%s' unknown", optarg);
71126e33 148 strncpy(User, pw->pw_name, (sizeof User)-1);
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149 User[(sizeof User)-1] = '\0';
150 break;
151 case 'l':
152 if (Option != opt_unknown)
153 usage("only one operation permitted");
154 Option = opt_list;
155 break;
156 case 'r':
157 if (Option != opt_unknown)
158 usage("only one operation permitted");
159 Option = opt_delete;
160 break;
161 case 'e':
162 if (Option != opt_unknown)
163 usage("only one operation permitted");
164 Option = opt_edit;
165 break;
166 default:
167 usage("unrecognized option");
168 }
169 }
170
171 endpwent();
172
173 if (Option != opt_unknown) {
174 if (argv[optind] != NULL) {
175 usage("no arguments permitted after this option");
176 }
177 } else {
178 if (argv[optind] != NULL) {
179 Option = opt_replace;
71126e33 180 strncpy (Filename, argv[optind], (sizeof Filename)-1);
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181 Filename[(sizeof Filename)-1] = '\0';
182
183 } else {
184 usage("file name must be specified for replace");
185 }
186 }
187
188 if (Option == opt_replace) {
189 /* we have to open the file here because we're going to
190 * chdir(2) into /var/cron before we get around to
191 * reading the file.
192 */
193 if (!strcmp(Filename, "-")) {
194 NewCrontab = stdin;
195 } else {
196 /* relinquish the setuid status of the binary during
197 * the open, lest nonroot users read files they should
198 * not be able to read. we can't use access() here
199 * since there's a race condition. thanks go out to
200 * Arnt Gulbrandsen <agulbra@pvv.unit.no> for spotting
201 * the race.
202 */
203
204 if (swap_uids() < OK)
205 err(ERROR_EXIT, "swapping uids");
206 if (!(NewCrontab = fopen(Filename, "r")))
207 err(ERROR_EXIT, "%s", Filename);
208 if (swap_uids() < OK)
209 err(ERROR_EXIT, "swapping uids back");
210 }
211 }
212
213 Debug(DMISC, ("user=%s, file=%s, option=%s\n",
214 User, Filename, Options[(int)Option]))
215}
216
217
218static void
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EN
219list_cmd(void)
220{
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221 char n[MAX_FNAME];
222 FILE *f;
223 int ch, x;
224
225 log_it(RealUser, Pid, "LIST", User);
71126e33 226 sprintf(n, CRON_TAB(User));
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MD
227 if (!(f = fopen(n, "r"))) {
228 if (errno == ENOENT)
229 errx(ERROR_EXIT, "no crontab for %s", User);
230 else
231 err(ERROR_EXIT, "%s", n);
232 }
233
234 /* file is open. copy to stdout, close.
235 */
236 Set_LineNum(1)
237
238 /* ignore the top few comments since we probably put them there.
239 */
240 for (x = 0; x < NHEADER_LINES; x++) {
241 ch = get_char(f);
242 if (EOF == ch)
243 break;
244 if ('#' != ch) {
245 putchar(ch);
246 break;
247 }
248 while (EOF != (ch = get_char(f)))
249 if (ch == '\n')
250 break;
251 if (EOF == ch)
252 break;
253 }
254
255 while (EOF != (ch = get_char(f)))
256 putchar(ch);
257 fclose(f);
258}
259
260
261static void
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EN
262delete_cmd(void)
263{
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MD
264 char n[MAX_FNAME];
265 int ch, first;
266
267 if (isatty(STDIN_FILENO)) {
71126e33 268 fprintf(stderr, "remove crontab for %s? ", User);
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269 first = ch = getchar();
270 while (ch != '\n' && ch != EOF)
271 ch = getchar();
272 if (first != 'y' && first != 'Y')
273 return;
274 }
275
276 log_it(RealUser, Pid, "DELETE", User);
71126e33 277 sprintf(n, CRON_TAB(User));
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278 if (unlink(n)) {
279 if (errno == ENOENT)
280 errx(ERROR_EXIT, "no crontab for %s", User);
281 else
282 err(ERROR_EXIT, "%s", n);
283 }
284 poke_daemon();
285}
286
287
288static void
3a2e6dbb 289check_error(char *msg)
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290{
291 CheckErrorCount++;
292 fprintf(stderr, "\"%s\":%d: %s\n", Filename, LineNumber-1, msg);
293}
294
295
296static void
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EN
297edit_cmd(void)
298{
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299 char n[MAX_FNAME], q[MAX_TEMPSTR], *editor;
300 FILE *f;
301 int ch, t, x;
302 struct stat statbuf, fsbuf;
303 time_t mtime;
304 WAIT_T waiter;
305 PID_T pid, xpid;
306 mode_t um;
307
308 log_it(RealUser, Pid, "BEGIN EDIT", User);
71126e33 309 sprintf(n, CRON_TAB(User));
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310 if (!(f = fopen(n, "r"))) {
311 if (errno != ENOENT)
312 err(ERROR_EXIT, "%s", n);
313 warnx("no crontab for %s - using an empty one", User);
314 if (!(f = fopen(_PATH_DEVNULL, "r")))
315 err(ERROR_EXIT, _PATH_DEVNULL);
316 }
317
318 um = umask(077);
71126e33 319 sprintf(Filename, "/tmp/crontab.XXXXXXXXXX");
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320 if ((t = mkstemp(Filename)) == -1) {
321 warn("%s", Filename);
71126e33 322 umask(um);
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323 goto fatal;
324 }
71126e33 325 umask(um);
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326#ifdef HAS_FCHOWN
327 if (fchown(t, getuid(), getgid()) < 0) {
328#else
329 if (chown(Filename, getuid(), getgid()) < 0) {
330#endif
331 warn("fchown");
332 goto fatal;
333 }
334 if (!(NewCrontab = fdopen(t, "r+"))) {
335 warn("fdopen");
336 goto fatal;
337 }
338
339 Set_LineNum(1)
340
341 /* ignore the top few comments since we probably put them there.
342 */
343 for (x = 0; x < NHEADER_LINES; x++) {
344 ch = get_char(f);
345 if (EOF == ch)
346 break;
347 if ('#' != ch) {
348 putc(ch, NewCrontab);
349 break;
350 }
351 while (EOF != (ch = get_char(f)))
352 if (ch == '\n')
353 break;
354 if (EOF == ch)
355 break;
356 }
357
358 /* copy the rest of the crontab (if any) to the temp file.
359 */
360 if (EOF != ch)
361 while (EOF != (ch = get_char(f)))
362 putc(ch, NewCrontab);
363 fclose(f);
364 if (fflush(NewCrontab))
365 err(ERROR_EXIT, "%s", Filename);
366 if (fstat(t, &fsbuf) < 0) {
367 warn("unable to fstat temp file");
368 goto fatal;
369 }
370 again:
371 if (stat(Filename, &statbuf) < 0) {
372 warn("stat");
373 fatal: unlink(Filename);
374 exit(ERROR_EXIT);
375 }
376 if (statbuf.st_dev != fsbuf.st_dev || statbuf.st_ino != fsbuf.st_ino)
377 errx(ERROR_EXIT, "temp file must be edited in place");
378 mtime = statbuf.st_mtime;
379
380 if ((!(editor = getenv("VISUAL")))
381 && (!(editor = getenv("EDITOR")))
382 ) {
383 editor = EDITOR;
384 }
385
386 /* we still have the file open. editors will generally rewrite the
387 * original file rather than renaming/unlinking it and starting a
388 * new one; even backup files are supposed to be made by copying
389 * rather than by renaming. if some editor does not support this,
390 * then don't use it. the security problems are more severe if we
391 * close and reopen the file around the edit.
392 */
393
394 switch (pid = fork()) {
395 case -1:
396 warn("fork");
397 goto fatal;
398 case 0:
399 /* child */
400 if (setuid(getuid()) < 0)
401 err(ERROR_EXIT, "setuid(getuid())");
402 if (chdir("/tmp") < 0)
403 err(ERROR_EXIT, "chdir(/tmp)");
404 if (strlen(editor) + strlen(Filename) + 2 >= MAX_TEMPSTR)
405 errx(ERROR_EXIT, "editor or filename too long");
406 execlp(editor, editor, Filename, NULL);
407 err(ERROR_EXIT, "%s", editor);
408 /*NOTREACHED*/
409 default:
410 /* parent */
411 break;
412 }
413
414 /* parent */
415 {
416 void (*f[4])();
417 f[0] = signal(SIGHUP, SIG_IGN);
418 f[1] = signal(SIGINT, SIG_IGN);
419 f[2] = signal(SIGTERM, SIG_IGN);
420 xpid = wait(&waiter);
421 signal(SIGHUP, f[0]);
422 signal(SIGINT, f[1]);
423 signal(SIGTERM, f[2]);
424 }
425 if (xpid != pid) {
426 warnx("wrong PID (%d != %d) from \"%s\"", xpid, pid, editor);
427 goto fatal;
428 }
429 if (WIFEXITED(waiter) && WEXITSTATUS(waiter)) {
430 warnx("\"%s\" exited with status %d", editor, WEXITSTATUS(waiter));
431 goto fatal;
432 }
433 if (WIFSIGNALED(waiter)) {
434 warnx("\"%s\" killed; signal %d (%score dumped)",
435 editor, WTERMSIG(waiter), WCOREDUMP(waiter) ?"" :"no ");
436 goto fatal;
437 }
438 if (stat(Filename, &statbuf) < 0) {
439 warn("stat");
440 goto fatal;
441 }
442 if (statbuf.st_dev != fsbuf.st_dev || statbuf.st_ino != fsbuf.st_ino)
443 errx(ERROR_EXIT, "temp file must be edited in place");
444 if (mtime == statbuf.st_mtime) {
445 warnx("no changes made to crontab");
446 goto remove;
447 }
448 warnx("installing new crontab");
449 switch (replace_cmd()) {
450 case 0:
451 break;
452 case -1:
453 for (;;) {
454 printf("Do you want to retry the same edit? ");
455 fflush(stdout);
456 q[0] = '\0';
71126e33 457 fgets(q, sizeof q, stdin);
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MD
458 switch (islower(q[0]) ? q[0] : tolower(q[0])) {
459 case 'y':
460 goto again;
461 case 'n':
462 goto abandon;
463 default:
464 fprintf(stderr, "Enter Y or N\n");
465 }
466 }
467 /*NOTREACHED*/
468 case -2:
469 abandon:
470 warnx("edits left in %s", Filename);
471 goto done;
472 default:
473 warnx("panic: bad switch() in replace_cmd()");
474 goto fatal;
475 }
476 remove:
477 unlink(Filename);
478 done:
479 log_it(RealUser, Pid, "END EDIT", User);
480}
481
482
483/* returns 0 on success
484 * -1 on syntax error
485 * -2 on install error
486 */
487static int
3a2e6dbb
EN
488replace_cmd(void)
489{
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490 char n[MAX_FNAME], envstr[MAX_ENVSTR], tn[MAX_FNAME];
491 FILE *tmp;
492 int ch, eof;
493 entry *e;
494 time_t now = time(NULL);
495 char **envp = env_init();
496
497 if (envp == NULL) {
498 warnx("cannot allocate memory");
499 return (-2);
500 }
501
71126e33
SW
502 sprintf(n, "tmp.%d", Pid);
503 sprintf(tn, CRON_TAB(n));
984263bc
MD
504 if (!(tmp = fopen(tn, "w+"))) {
505 warn("%s", tn);
506 return (-2);
507 }
508
509 /* write a signature at the top of the file.
510 *
511 * VERY IMPORTANT: make sure NHEADER_LINES agrees with this code.
512 */
513 fprintf(tmp, "# DO NOT EDIT THIS FILE - edit the master and reinstall.\n");
514 fprintf(tmp, "# (%s installed on %-24.24s)\n", Filename, ctime(&now));
984263bc
MD
515
516 /* copy the crontab to the tmp
517 */
518 rewind(NewCrontab);
519 Set_LineNum(1)
520 while (EOF != (ch = get_char(NewCrontab)))
521 putc(ch, tmp);
522 ftruncate(fileno(tmp), ftell(tmp));
523 fflush(tmp); rewind(tmp);
524
525 if (ferror(tmp)) {
526 warnx("error while writing new crontab to %s", tn);
527 fclose(tmp); unlink(tn);
528 return (-2);
529 }
530
531 /* check the syntax of the file being installed.
532 */
533
534 /* BUG: was reporting errors after the EOF if there were any errors
535 * in the file proper -- kludged it by stopping after first error.
536 * vix 31mar87
537 */
538 Set_LineNum(1 - NHEADER_LINES)
539 CheckErrorCount = 0; eof = FALSE;
540 while (!CheckErrorCount && !eof) {
541 switch (load_env(envstr, tmp)) {
542 case ERR:
543 eof = TRUE;
544 break;
545 case FALSE:
546 e = load_entry(tmp, check_error, pw, envp);
547 if (e)
548 free(e);
549 break;
550 case TRUE:
551 break;
552 }
553 }
554
555 if (CheckErrorCount != 0) {
556 warnx("errors in crontab file, can't install");
557 fclose(tmp); unlink(tn);
558 return (-1);
559 }
560
561#ifdef HAS_FCHOWN
562 if (fchown(fileno(tmp), ROOT_UID, -1) < OK)
563#else
564 if (chown(tn, ROOT_UID, -1) < OK)
565#endif
566 {
567 warn("chown");
568 fclose(tmp); unlink(tn);
569 return (-2);
570 }
571
572#ifdef HAS_FCHMOD
573 if (fchmod(fileno(tmp), 0600) < OK)
574#else
575 if (chmod(tn, 0600) < OK)
576#endif
577 {
578 warn("chown");
579 fclose(tmp); unlink(tn);
580 return (-2);
581 }
582
583 if (fclose(tmp) == EOF) {
584 warn("fclose");
585 unlink(tn);
586 return (-2);
587 }
588
71126e33 589 sprintf(n, CRON_TAB(User));
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MD
590 if (rename(tn, n)) {
591 warn("error renaming %s to %s", tn, n);
592 unlink(tn);
593 return (-2);
594 }
595 log_it(RealUser, Pid, "REPLACE", User);
596
597 poke_daemon();
598
599 return (0);
600}
601
602
603static void
3a2e6dbb
EN
604poke_daemon(void)
605{
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MD
606#ifdef USE_UTIMES
607 struct timeval tvs[2];
608 struct timezone tz;
609
71126e33 610 gettimeofday(&tvs[0], &tz);
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MD
611 tvs[1] = tvs[0];
612 if (utimes(SPOOL_DIR, tvs) < OK) {
613 warn("can't update mtime on spooldir %s", SPOOL_DIR);
614 return;
615 }
616#else
617 if (utime(SPOOL_DIR, NULL) < OK) {
618 warn("can't update mtime on spooldir %s", SPOOL_DIR);
619 return;
620 }
621#endif /*USE_UTIMES*/
622}