1 /* Copyright 1988,1990,1993,1994 by Paul Vixie
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
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
16 * From Id: crontab.c,v 2.13 1994/01/17 03:20:37 vixie Exp
19 #if !defined(lint) && !defined(LINT)
20 static const char rcsid[] =
24 /* crontab - install and manage per-user crontab files
25 * vix 02may87 [RCS has the rest of the log]
26 * vix 26jan87 [original]
39 # include <sys/time.h>
49 #define NHEADER_LINES 3
52 enum opt_t { opt_unknown, opt_list, opt_delete, opt_edit, opt_replace };
55 static char *Options[] = { "???", "list", "delete", "edit", "replace" };
60 static char User[MAX_UNAME], RealUser[MAX_UNAME];
61 static char Filename[MAX_FNAME];
62 static FILE *NewCrontab;
63 static int CheckErrorCount;
64 static enum opt_t Option;
65 static struct passwd *pw;
66 static void list_cmd __P((void)),
67 delete_cmd __P((void)),
69 poke_daemon __P((void)),
70 check_error __P((char *)),
71 parse_args __P((int c, char *v[]));
72 static int replace_cmd __P((void));
79 fprintf(stderr, "crontab: usage error: %s\n", msg);
80 fprintf(stderr, "%s\n%s\n",
81 "usage: crontab [-u user] file",
82 " crontab [-u user] { -e | -l | -r }");
95 ProgramName = argv[0];
98 setlocale(LC_ALL, "");
104 parse_args(argc, argv); /* sets many globals, opens a file */
107 if (!allowed(User)) {
108 warnx("you (%s) are not allowed to use this program", User);
109 log_it(RealUser, Pid, "AUTH", "crontab command not allowed");
112 exitstatus = OK_EXIT;
114 case opt_list: list_cmd();
116 case opt_delete: delete_cmd();
118 case opt_edit: edit_cmd();
120 case opt_replace: if (replace_cmd() < 0)
121 exitstatus = ERROR_EXIT;
132 parse_args(argc, argv)
137 char resolved_path[PATH_MAX];
139 if (!(pw = getpwuid(getuid())))
140 errx(ERROR_EXIT, "your UID isn't in the passwd file, bailing out");
141 (void) strncpy(User, pw->pw_name, (sizeof User)-1);
142 User[(sizeof User)-1] = '\0';
143 strcpy(RealUser, User);
145 Option = opt_unknown;
146 while ((argch = getopt(argc, argv, "u:lerx:")) != -1) {
149 if (!set_debug_flags(optarg))
150 usage("bad debug option");
153 if (getuid() != ROOT_UID)
154 errx(ERROR_EXIT, "must be privileged to use -u");
155 if (!(pw = getpwnam(optarg)))
156 errx(ERROR_EXIT, "user `%s' unknown", optarg);
157 (void) strncpy(User, pw->pw_name, (sizeof User)-1);
158 User[(sizeof User)-1] = '\0';
161 if (Option != opt_unknown)
162 usage("only one operation permitted");
166 if (Option != opt_unknown)
167 usage("only one operation permitted");
171 if (Option != opt_unknown)
172 usage("only one operation permitted");
176 usage("unrecognized option");
182 if (Option != opt_unknown) {
183 if (argv[optind] != NULL) {
184 usage("no arguments permitted after this option");
187 if (argv[optind] != NULL) {
188 Option = opt_replace;
189 (void) strncpy (Filename, argv[optind], (sizeof Filename)-1);
190 Filename[(sizeof Filename)-1] = '\0';
193 usage("file name must be specified for replace");
197 if (Option == opt_replace) {
198 /* we have to open the file here because we're going to
199 * chdir(2) into /var/cron before we get around to
202 if (!strcmp(Filename, "-")) {
204 } else if (realpath(Filename, resolved_path) != NULL &&
205 !strcmp(resolved_path, SYSCRONTAB)) {
206 err(ERROR_EXIT, SYSCRONTAB " must be edited manually");
208 /* relinquish the setuid status of the binary during
209 * the open, lest nonroot users read files they should
210 * not be able to read. we can't use access() here
211 * since there's a race condition. thanks go out to
212 * Arnt Gulbrandsen <agulbra@pvv.unit.no> for spotting
216 if (swap_uids() < OK)
217 err(ERROR_EXIT, "swapping uids");
218 if (!(NewCrontab = fopen(Filename, "r")))
219 err(ERROR_EXIT, "%s", Filename);
220 if (swap_uids() < OK)
221 err(ERROR_EXIT, "swapping uids back");
225 Debug(DMISC, ("user=%s, file=%s, option=%s\n",
226 User, Filename, Options[(int)Option]))
230 copy_file(FILE *in, FILE *out) {
234 /* ignore the top few comments since we probably put them there.
236 for (x = 0; x < NHEADER_LINES; x++) {
244 while (EOF != (ch = get_char(in)))
251 /* copy the rest of the crontab (if any) to the output file.
254 while (EOF != (ch = get_char(in)))
263 log_it(RealUser, Pid, "LIST", User);
264 (void) sprintf(n, CRON_TAB(User));
265 if (!(f = fopen(n, "r"))) {
267 errx(ERROR_EXIT, "no crontab for %s", User);
269 err(ERROR_EXIT, "%s", n);
272 /* file is open. copy to stdout, close.
274 copy_file(f, stdout);
284 if (isatty(STDIN_FILENO)) {
285 (void)fprintf(stderr, "remove crontab for %s? ", User);
286 first = ch = getchar();
287 while (ch != '\n' && ch != EOF)
289 if (first != 'y' && first != 'Y')
293 log_it(RealUser, Pid, "DELETE", User);
294 (void) sprintf(n, CRON_TAB(User));
297 errx(ERROR_EXIT, "no crontab for %s", User);
299 err(ERROR_EXIT, "%s", n);
310 fprintf(stderr, "\"%s\":%d: %s\n", Filename, LineNumber-1, msg);
316 char n[MAX_FNAME], q[MAX_TEMPSTR], *editor;
319 struct stat statbuf, fsbuf;
323 int syntax_error = 0;
324 char orig_md5[MD5_SIZE];
325 char new_md5[MD5_SIZE];
327 log_it(RealUser, Pid, "BEGIN EDIT", User);
328 (void) sprintf(n, CRON_TAB(User));
329 if (!(f = fopen(n, "r"))) {
331 err(ERROR_EXIT, "%s", n);
332 warnx("no crontab for %s - using an empty one", User);
333 if (!(f = fopen(_PATH_DEVNULL, "r")))
334 err(ERROR_EXIT, _PATH_DEVNULL);
338 (void) sprintf(Filename, "/tmp/crontab.XXXXXXXXXX");
339 if ((t = mkstemp(Filename)) == -1) {
340 warn("%s", Filename);
346 if (fchown(t, getuid(), getgid()) < 0) {
348 if (chown(Filename, getuid(), getgid()) < 0) {
353 if (!(NewCrontab = fdopen(t, "r+"))) {
358 copy_file(f, NewCrontab);
360 if (fflush(NewCrontab))
361 err(ERROR_EXIT, "%s", Filename);
362 if (fstat(t, &fsbuf) < 0) {
363 warn("unable to fstat temp file");
367 if (stat(Filename, &statbuf) < 0) {
369 fatal: unlink(Filename);
372 if (statbuf.st_dev != fsbuf.st_dev || statbuf.st_ino != fsbuf.st_ino)
373 errx(ERROR_EXIT, "temp file must be edited in place");
374 if (MD5File(Filename, orig_md5) == NULL) {
379 if ((!(editor = getenv("VISUAL")))
380 && (!(editor = getenv("EDITOR")))
385 /* we still have the file open. editors will generally rewrite the
386 * original file rather than renaming/unlinking it and starting a
387 * new one; even backup files are supposed to be made by copying
388 * rather than by renaming. if some editor does not support this,
389 * then don't use it. the security problems are more severe if we
390 * close and reopen the file around the edit.
393 switch (pid = fork()) {
399 if (setuid(getuid()) < 0)
400 err(ERROR_EXIT, "setuid(getuid())");
401 if (chdir("/tmp") < 0)
402 err(ERROR_EXIT, "chdir(/tmp)");
403 if (strlen(editor) + strlen(Filename) + 2 >= MAX_TEMPSTR)
404 errx(ERROR_EXIT, "editor or filename too long");
405 execlp(editor, editor, Filename, (char *)NULL);
406 err(ERROR_EXIT, "%s", editor);
416 f[0] = signal(SIGHUP, SIG_IGN);
417 f[1] = signal(SIGINT, SIG_IGN);
418 f[2] = signal(SIGTERM, SIG_IGN);
419 xpid = wait(&waiter);
420 signal(SIGHUP, f[0]);
421 signal(SIGINT, f[1]);
422 signal(SIGTERM, f[2]);
425 warnx("wrong PID (%d != %d) from \"%s\"", xpid, pid, editor);
428 if (WIFEXITED(waiter) && WEXITSTATUS(waiter)) {
429 warnx("\"%s\" exited with status %d", editor, WEXITSTATUS(waiter));
432 if (WIFSIGNALED(waiter)) {
433 warnx("\"%s\" killed; signal %d (%score dumped)",
434 editor, WTERMSIG(waiter), WCOREDUMP(waiter) ?"" :"no ");
437 if (stat(Filename, &statbuf) < 0) {
441 if (statbuf.st_dev != fsbuf.st_dev || statbuf.st_ino != fsbuf.st_ino)
442 errx(ERROR_EXIT, "temp file must be edited in place");
443 if (MD5File(Filename, new_md5) == NULL) {
447 if (strcmp(orig_md5, new_md5) == 0 && !syntax_error) {
448 warnx("no changes made to crontab");
451 warnx("installing new crontab");
452 switch (replace_cmd()) {
453 case 0: /* Success */
455 case -1: /* Syntax error */
457 printf("Do you want to retry the same edit? ");
460 (void) fgets(q, sizeof q, stdin);
461 switch (islower(q[0]) ? q[0] : tolower(q[0])) {
468 fprintf(stderr, "Enter Y or N\n");
472 case -2: /* Install error */
474 warnx("edits left in %s", Filename);
477 warnx("panic: bad switch() in replace_cmd()");
483 log_it(RealUser, Pid, "END EDIT", User);
487 /* returns 0 on success
489 * -2 on install error
493 char n[MAX_FNAME], envstr[MAX_ENVSTR], tn[MAX_FNAME];
497 time_t now = time(NULL);
498 char **envp = env_init();
501 warnx("cannot allocate memory");
505 (void) sprintf(n, "tmp.%d", Pid);
506 (void) sprintf(tn, CRON_TAB(n));
507 if (!(tmp = fopen(tn, "w+"))) {
512 /* write a signature at the top of the file.
514 * VERY IMPORTANT: make sure NHEADER_LINES agrees with this code.
516 fprintf(tmp, "# DO NOT EDIT THIS FILE - edit the master and reinstall.\n");
517 fprintf(tmp, "# (%s installed on %-24.24s)\n", Filename, ctime(&now));
518 fprintf(tmp, "# (Cron version -- %s)\n", rcsid);
520 /* copy the crontab to the tmp
524 while (EOF != (ch = get_char(NewCrontab)))
526 ftruncate(fileno(tmp), ftell(tmp));
527 fflush(tmp); rewind(tmp);
530 warnx("error while writing new crontab to %s", tn);
531 fclose(tmp); unlink(tn);
535 /* check the syntax of the file being installed.
538 /* BUG: was reporting errors after the EOF if there were any errors
539 * in the file proper -- kludged it by stopping after first error.
542 Set_LineNum(1 - NHEADER_LINES)
543 CheckErrorCount = 0; eof = FALSE;
544 while (!CheckErrorCount && !eof) {
545 switch (load_env(envstr, tmp)) {
550 e = load_entry(tmp, check_error, pw, envp);
559 if (CheckErrorCount != 0) {
560 warnx("errors in crontab file, can't install");
561 fclose(tmp); unlink(tn);
566 if (fchown(fileno(tmp), ROOT_UID, -1) < OK)
568 if (chown(tn, ROOT_UID, -1) < OK)
572 fclose(tmp); unlink(tn);
577 if (fchmod(fileno(tmp), 0600) < OK)
579 if (chmod(tn, 0600) < OK)
583 fclose(tmp); unlink(tn);
587 if (fclose(tmp) == EOF) {
593 (void) sprintf(n, CRON_TAB(User));
595 warn("error renaming %s to %s", tn, n);
599 log_it(RealUser, Pid, "REPLACE", User);
610 struct timeval tvs[2];
613 (void) gettimeofday(&tvs[0], &tz);
615 if (utimes(SPOOL_DIR, tvs) < OK) {
616 warn("can't update mtime on spooldir %s", SPOOL_DIR);
620 if (utime(SPOOL_DIR, NULL) < OK) {
621 warn("can't update mtime on spooldir %s", SPOOL_DIR);
624 #endif /*USE_UTIMES*/