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
16 */
17
18 #if !defined(lint) && !defined(LINT)
19 static const char rcsid[] =
20 "$FreeBSD$";
21 #endif
22
23 /* vix 26jan87 [RCS'd; rest of log is in RCS file]
24 * vix 01jan87 [added line-level error recovery]
25 * vix 31dec86 [added /step to the from-to range, per bob@acornrc]
26 * vix 30dec86 [written]
27 */
28
29
30 #include "cron.h"
31 #include <grp.h>
32 #ifdef LOGIN_CAP
33 #include <login_cap.h>
34 #endif
35
36 typedef enum ecode {
37 e_none, e_minute, e_hour, e_dom, e_month, e_dow,
38 e_cmd, e_timespec, e_username, e_group, e_mem
39 #ifdef LOGIN_CAP
40 , e_class
41 #endif
42 } ecode_e;
43
44 static char get_list(bitstr_t *, int, int, char *[], int, FILE *),
45 get_range(bitstr_t *, int, int, char *[], int, FILE *),
46 get_number(int *, int, char *[], int, FILE *);
47 static int set_element(bitstr_t *, int, int, int);
48
49 static char *ecodes[] =
50 {
51 "no error",
52 "bad minute",
53 "bad hour",
54 "bad day-of-month",
55 "bad month",
56 "bad day-of-week",
57 "bad command",
58 "bad time specifier",
59 "bad username",
60 "bad group name",
61 "out of memory",
62 #ifdef LOGIN_CAP
63 "bad class name",
64 #endif
65 };
66
67
68 void
free_entry(e)69 free_entry(e)
70 entry *e;
71 {
72 #ifdef LOGIN_CAP
73 if (e->class != NULL)
74 free(e->class);
75 #endif
76 if (e->cmd != NULL)
77 free(e->cmd);
78 if (e->envp != NULL)
79 env_free(e->envp);
80 free(e);
81 }
82
83
84 /* return NULL if eof or syntax error occurs;
85 * otherwise return a pointer to a new entry.
86 */
87 entry *
load_entry(file,error_func,pw,envp)88 load_entry(file, error_func, pw, envp)
89 FILE *file;
90 void (*error_func)(char *);
91 struct passwd *pw;
92 char **envp;
93 {
94 /* this function reads one crontab entry -- the next -- from a file.
95 * it skips any leading blank lines, ignores comments, and returns
96 * EOF if for any reason the entry can't be read and parsed.
97 *
98 * the entry is also parsed here.
99 *
100 * syntax:
101 * user crontab:
102 * minutes hours doms months dows cmd\n
103 * system crontab (/etc/crontab):
104 * minutes hours doms months dows USERNAME cmd\n
105 */
106
107 ecode_e ecode = e_none;
108 entry *e;
109 int ch;
110 char cmd[MAX_COMMAND];
111 char envstr[MAX_ENVSTR];
112 char **prev_env;
113
114 Debug(DPARS, ("load_entry()...about to eat comments\n"))
115
116 skip_comments(file);
117
118 ch = get_char(file);
119 if (ch == EOF)
120 return NULL;
121
122 /* ch is now the first useful character of a useful line.
123 * it may be an @special or it may be the first character
124 * of a list of minutes.
125 */
126
127 e = (entry *) calloc(sizeof(entry), sizeof(char));
128
129 if (e == NULL) {
130 warn("load_entry: calloc failed");
131 return NULL;
132 }
133
134 if (ch == '@') {
135 /* all of these should be flagged and load-limited; i.e.,
136 * instead of @hourly meaning "0 * * * *" it should mean
137 * "close to the front of every hour but not 'til the
138 * system load is low". Problems are: how do you know
139 * what "low" means? (save me from /etc/cron.conf!) and:
140 * how to guarantee low variance (how low is low?), which
141 * means how to we run roughly every hour -- seems like
142 * we need to keep a history or let the first hour set
143 * the schedule, which means we aren't load-limited
144 * anymore. too much for my overloaded brain. (vix, jan90)
145 * HINT
146 */
147 Debug(DPARS, ("load_entry()...about to test shortcuts\n"))
148 ch = get_string(cmd, MAX_COMMAND, file, " \t\n");
149 if (!strcmp("reboot", cmd)) {
150 Debug(DPARS, ("load_entry()...reboot shortcut\n"))
151 e->flags |= WHEN_REBOOT;
152 } else if (!strcmp("yearly", cmd) || !strcmp("annually", cmd)){
153 Debug(DPARS, ("load_entry()...yearly shortcut\n"))
154 bit_set(e->second, 0);
155 bit_set(e->minute, 0);
156 bit_set(e->hour, 0);
157 bit_set(e->dom, 0);
158 bit_set(e->month, 0);
159 bit_nset(e->dow, 0, (LAST_DOW-FIRST_DOW+1));
160 e->flags |= DOW_STAR;
161 } else if (!strcmp("monthly", cmd)) {
162 Debug(DPARS, ("load_entry()...monthly shortcut\n"))
163 bit_set(e->second, 0);
164 bit_set(e->minute, 0);
165 bit_set(e->hour, 0);
166 bit_set(e->dom, 0);
167 bit_nset(e->month, 0, (LAST_MONTH-FIRST_MONTH+1));
168 bit_nset(e->dow, 0, (LAST_DOW-FIRST_DOW+1));
169 e->flags |= DOW_STAR;
170 } else if (!strcmp("weekly", cmd)) {
171 Debug(DPARS, ("load_entry()...weekly shortcut\n"))
172 bit_set(e->second, 0);
173 bit_set(e->minute, 0);
174 bit_set(e->hour, 0);
175 bit_nset(e->dom, 0, (LAST_DOM-FIRST_DOM+1));
176 e->flags |= DOM_STAR;
177 bit_nset(e->month, 0, (LAST_MONTH-FIRST_MONTH+1));
178 bit_set(e->dow, 0);
179 } else if (!strcmp("daily", cmd) || !strcmp("midnight", cmd)) {
180 Debug(DPARS, ("load_entry()...daily shortcut\n"))
181 bit_set(e->second, 0);
182 bit_set(e->minute, 0);
183 bit_set(e->hour, 0);
184 bit_nset(e->dom, 0, (LAST_DOM-FIRST_DOM+1));
185 bit_nset(e->month, 0, (LAST_MONTH-FIRST_MONTH+1));
186 bit_nset(e->dow, 0, (LAST_DOW-FIRST_DOW+1));
187 } else if (!strcmp("hourly", cmd)) {
188 Debug(DPARS, ("load_entry()...hourly shortcut\n"))
189 bit_set(e->second, 0);
190 bit_set(e->minute, 0);
191 bit_nset(e->hour, 0, (LAST_HOUR-FIRST_HOUR+1));
192 bit_nset(e->dom, 0, (LAST_DOM-FIRST_DOM+1));
193 bit_nset(e->month, 0, (LAST_MONTH-FIRST_MONTH+1));
194 bit_nset(e->dow, 0, (LAST_DOW-FIRST_DOW+1));
195 } else if (!strcmp("every_minute", cmd)) {
196 Debug(DPARS, ("load_entry()...every_minute shortcut\n"))
197 bit_set(e->second, 0);
198 bit_nset(e->minute, 0, (LAST_MINUTE-FIRST_MINUTE+1));
199 bit_nset(e->hour, 0, (LAST_HOUR-FIRST_HOUR+1));
200 bit_nset(e->dom, 0, (LAST_DOM-FIRST_DOM+1));
201 bit_nset(e->month, 0, (LAST_MONTH-FIRST_MONTH+1));
202 bit_nset(e->dow, 0, (LAST_DOW-FIRST_DOW+1));
203 } else if (!strcmp("every_second", cmd)) {
204 Debug(DPARS, ("load_entry()...every_second shortcut\n"))
205 e->flags |= SEC_RES;
206 bit_nset(e->second, 0, (LAST_SECOND-FIRST_SECOND+1));
207 bit_nset(e->minute, 0, (LAST_MINUTE-FIRST_MINUTE+1));
208 bit_nset(e->hour, 0, (LAST_HOUR-FIRST_HOUR+1));
209 bit_nset(e->dom, 0, (LAST_DOM-FIRST_DOM+1));
210 bit_nset(e->month, 0, (LAST_MONTH-FIRST_MONTH+1));
211 bit_nset(e->dow, 0, (LAST_DOW-FIRST_DOW+1));
212 } else {
213 ecode = e_timespec;
214 goto eof;
215 }
216 /* Advance past whitespace between shortcut and
217 * username/command.
218 */
219 Skip_Blanks(ch, file);
220 if (ch == EOF) {
221 ecode = e_cmd;
222 goto eof;
223 }
224 } else {
225 Debug(DPARS, ("load_entry()...about to parse numerics\n"))
226 bit_set(e->second, 0);
227
228 ch = get_list(e->minute, FIRST_MINUTE, LAST_MINUTE,
229 PPC_NULL, ch, file);
230 if (ch == EOF) {
231 ecode = e_minute;
232 goto eof;
233 }
234
235 /* hours
236 */
237
238 ch = get_list(e->hour, FIRST_HOUR, LAST_HOUR,
239 PPC_NULL, ch, file);
240 if (ch == EOF) {
241 ecode = e_hour;
242 goto eof;
243 }
244
245 /* DOM (days of month)
246 */
247
248 if (ch == '*')
249 e->flags |= DOM_STAR;
250 ch = get_list(e->dom, FIRST_DOM, LAST_DOM,
251 PPC_NULL, ch, file);
252 if (ch == EOF) {
253 ecode = e_dom;
254 goto eof;
255 }
256
257 /* month
258 */
259
260 ch = get_list(e->month, FIRST_MONTH, LAST_MONTH,
261 MonthNames, ch, file);
262 if (ch == EOF) {
263 ecode = e_month;
264 goto eof;
265 }
266
267 /* DOW (days of week)
268 */
269
270 if (ch == '*')
271 e->flags |= DOW_STAR;
272 ch = get_list(e->dow, FIRST_DOW, LAST_DOW,
273 DowNames, ch, file);
274 if (ch == EOF) {
275 ecode = e_dow;
276 goto eof;
277 }
278 }
279
280 /* make sundays equivalent */
281 if (bit_test(e->dow, 0) || bit_test(e->dow, 7)) {
282 bit_set(e->dow, 0);
283 bit_set(e->dow, 7);
284 }
285
286 /* ch is the first character of a command, or a username */
287 unget_char(ch, file);
288
289 if (!pw) {
290 char *username = cmd; /* temp buffer */
291 char *s;
292 struct group *grp;
293 #ifdef LOGIN_CAP
294 login_cap_t *lc;
295 #endif
296
297 Debug(DPARS, ("load_entry()...about to parse username\n"))
298 ch = get_string(username, MAX_COMMAND, file, " \t");
299
300 Debug(DPARS, ("load_entry()...got %s\n",username))
301 if (ch == EOF) {
302 ecode = e_cmd;
303 goto eof;
304 }
305
306 #ifdef LOGIN_CAP
307 if ((s = strrchr(username, '/')) != NULL) {
308 *s = '\0';
309 e->class = strdup(s + 1);
310 if (e->class == NULL)
311 warn("strdup(\"%s\")", s + 1);
312 } else {
313 e->class = strdup(RESOURCE_RC);
314 if (e->class == NULL)
315 warn("strdup(\"%s\")", RESOURCE_RC);
316 }
317 if (e->class == NULL) {
318 ecode = e_mem;
319 goto eof;
320 }
321 if ((lc = login_getclass(e->class)) == NULL) {
322 ecode = e_class;
323 goto eof;
324 }
325 login_close(lc);
326 #endif
327 grp = NULL;
328 if ((s = strrchr(username, ':')) != NULL) {
329 *s = '\0';
330 if ((grp = getgrnam(s + 1)) == NULL) {
331 ecode = e_group;
332 goto eof;
333 }
334 }
335
336 pw = getpwnam(username);
337 if (pw == NULL) {
338 ecode = e_username;
339 goto eof;
340 }
341 if (grp != NULL)
342 pw->pw_gid = grp->gr_gid;
343 Debug(DPARS, ("load_entry()...uid %d, gid %d\n",pw->pw_uid,pw->pw_gid))
344 #ifdef LOGIN_CAP
345 Debug(DPARS, ("load_entry()...class %s\n",e->class))
346 #endif
347 }
348
349 #ifndef PAM /* PAM takes care of account expiration by itself */
350 if (pw->pw_expire && time(NULL) >= pw->pw_expire) {
351 ecode = e_username;
352 goto eof;
353 }
354 #endif /* !PAM */
355
356 e->uid = pw->pw_uid;
357 e->gid = pw->pw_gid;
358
359 /* copy and fix up environment. some variables are just defaults and
360 * others are overrides.
361 */
362 e->envp = env_copy(envp);
363 if (e->envp == NULL) {
364 warn("env_copy");
365 ecode = e_mem;
366 goto eof;
367 }
368 if (!env_get("SHELL", e->envp)) {
369 prev_env = e->envp;
370 sprintf(envstr, "SHELL=%s", _PATH_BSHELL);
371 e->envp = env_set(e->envp, envstr);
372 if (e->envp == NULL) {
373 warn("env_set(%s)", envstr);
374 env_free(prev_env);
375 ecode = e_mem;
376 goto eof;
377 }
378 }
379 if (!env_get("HOME", e->envp)) {
380 prev_env = e->envp;
381 sprintf(envstr, "HOME=%s", pw->pw_dir);
382 e->envp = env_set(e->envp, envstr);
383 if (e->envp == NULL) {
384 warn("env_set(%s)", envstr);
385 env_free(prev_env);
386 ecode = e_mem;
387 goto eof;
388 }
389 }
390 if (!env_get("PATH", e->envp)) {
391 prev_env = e->envp;
392 sprintf(envstr, "PATH=%s", _PATH_DEFPATH);
393 e->envp = env_set(e->envp, envstr);
394 if (e->envp == NULL) {
395 warn("env_set(%s)", envstr);
396 env_free(prev_env);
397 ecode = e_mem;
398 goto eof;
399 }
400 }
401 prev_env = e->envp;
402 sprintf(envstr, "%s=%s", "LOGNAME", pw->pw_name);
403 e->envp = env_set(e->envp, envstr);
404 if (e->envp == NULL) {
405 warn("env_set(%s)", envstr);
406 env_free(prev_env);
407 ecode = e_mem;
408 goto eof;
409 }
410 #if defined(BSD)
411 prev_env = e->envp;
412 sprintf(envstr, "%s=%s", "USER", pw->pw_name);
413 e->envp = env_set(e->envp, envstr);
414 if (e->envp == NULL) {
415 warn("env_set(%s)", envstr);
416 env_free(prev_env);
417 ecode = e_mem;
418 goto eof;
419 }
420 #endif
421
422 Debug(DPARS, ("load_entry()...about to parse command\n"))
423
424 /* Everything up to the next \n or EOF is part of the command...
425 * too bad we don't know in advance how long it will be, since we
426 * need to malloc a string for it... so, we limit it to MAX_COMMAND.
427 * XXX - should use realloc().
428 */
429 ch = get_string(cmd, MAX_COMMAND, file, "\n");
430
431 /* a file without a \n before the EOF is rude, so we'll complain...
432 */
433 if (ch == EOF) {
434 ecode = e_cmd;
435 goto eof;
436 }
437
438 /* got the command in the 'cmd' string; save it in *e.
439 */
440 e->cmd = strdup(cmd);
441 if (e->cmd == NULL) {
442 warn("strdup(\"%s\")", cmd);
443 ecode = e_mem;
444 goto eof;
445 }
446 Debug(DPARS, ("load_entry()...returning successfully\n"))
447
448 /* success, fini, return pointer to the entry we just created...
449 */
450 return e;
451
452 eof:
453 free_entry(e);
454 if (ecode != e_none && error_func)
455 (*error_func)(ecodes[(int)ecode]);
456 while (ch != EOF && ch != '\n')
457 ch = get_char(file);
458 return NULL;
459 }
460
461
462 static char
get_list(bits,low,high,names,ch,file)463 get_list(bits, low, high, names, ch, file)
464 bitstr_t *bits; /* one bit per flag, default=FALSE */
465 int low, high; /* bounds, impl. offset for bitstr */
466 char *names[]; /* NULL or *[] of names for these elements */
467 int ch; /* current character being processed */
468 FILE *file; /* file being read */
469 {
470 register int done;
471
472 /* we know that we point to a non-blank character here;
473 * must do a Skip_Blanks before we exit, so that the
474 * next call (or the code that picks up the cmd) can
475 * assume the same thing.
476 */
477
478 Debug(DPARS|DEXT, ("get_list()...entered\n"))
479
480 /* list = range {"," range}
481 */
482
483 /* clear the bit string, since the default is 'off'.
484 */
485 bit_nclear(bits, 0, (high-low+1));
486
487 /* process all ranges
488 */
489 done = FALSE;
490 while (!done) {
491 ch = get_range(bits, low, high, names, ch, file);
492 if (ch == ',')
493 ch = get_char(file);
494 else
495 done = TRUE;
496 }
497
498 /* exiting. skip to some blanks, then skip over the blanks.
499 */
500 Skip_Nonblanks(ch, file)
501 Skip_Blanks(ch, file)
502
503 Debug(DPARS|DEXT, ("get_list()...exiting w/ %02x\n", ch))
504
505 return ch;
506 }
507
508
509 static char
get_range(bits,low,high,names,ch,file)510 get_range(bits, low, high, names, ch, file)
511 bitstr_t *bits; /* one bit per flag, default=FALSE */
512 int low, high; /* bounds, impl. offset for bitstr */
513 char *names[]; /* NULL or names of elements */
514 int ch; /* current character being processed */
515 FILE *file; /* file being read */
516 {
517 /* range = number | number "-" number [ "/" number ]
518 */
519
520 register int i;
521 auto int num1, num2, num3;
522
523 Debug(DPARS|DEXT, ("get_range()...entering, exit won't show\n"))
524
525 if (ch == '*') {
526 /* '*' means "first-last" but can still be modified by /step
527 */
528 num1 = low;
529 num2 = high;
530 ch = get_char(file);
531 if (ch == EOF)
532 return EOF;
533 } else {
534 if (EOF == (ch = get_number(&num1, low, names, ch, file)))
535 return EOF;
536
537 if (ch == '/')
538 num2 = high;
539 else if (ch != '-') {
540 /* not a range, it's a single number.
541 */
542 if (EOF == set_element(bits, low, high, num1))
543 return EOF;
544 return ch;
545 } else {
546 /* eat the dash
547 */
548 ch = get_char(file);
549 if (ch == EOF)
550 return EOF;
551
552 /* get the number following the dash
553 */
554 ch = get_number(&num2, low, names, ch, file);
555 if (ch == EOF)
556 return EOF;
557 }
558 }
559
560 /* check for step size
561 */
562 if (ch == '/') {
563 /* eat the slash
564 */
565 ch = get_char(file);
566 if (ch == EOF)
567 return EOF;
568
569 /* get the step size -- note: we don't pass the
570 * names here, because the number is not an
571 * element id, it's a step size. 'low' is
572 * sent as a 0 since there is no offset either.
573 */
574 ch = get_number(&num3, 0, PPC_NULL, ch, file);
575 if (ch == EOF || num3 == 0)
576 return EOF;
577 } else {
578 /* no step. default==1.
579 */
580 num3 = 1;
581 }
582
583 /* range. set all elements from num1 to num2, stepping
584 * by num3. (the step is a downward-compatible extension
585 * proposed conceptually by bob@acornrc, syntactically
586 * designed then implmented by paul vixie).
587 */
588 for (i = num1; i <= num2; i += num3)
589 if (EOF == set_element(bits, low, high, i))
590 return EOF;
591
592 return ch;
593 }
594
595
596 static char
get_number(numptr,low,names,ch,file)597 get_number(numptr, low, names, ch, file)
598 int *numptr; /* where does the result go? */
599 int low; /* offset applied to result if symbolic enum used */
600 char *names[]; /* symbolic names, if any, for enums */
601 int ch; /* current character */
602 FILE *file; /* source */
603 {
604 char temp[MAX_TEMPSTR], *pc;
605 int len, i, all_digits;
606
607 /* collect alphanumerics into our fixed-size temp array
608 */
609 pc = temp;
610 len = 0;
611 all_digits = TRUE;
612 while (isalnum(ch)) {
613 if (++len >= MAX_TEMPSTR)
614 return EOF;
615
616 *pc++ = ch;
617
618 if (!isdigit(ch))
619 all_digits = FALSE;
620
621 ch = get_char(file);
622 }
623 *pc = '\0';
624 if (len == 0)
625 return (EOF);
626
627 /* try to find the name in the name list
628 */
629 if (names) {
630 for (i = 0; names[i] != NULL; i++) {
631 Debug(DPARS|DEXT,
632 ("get_num, compare(%s,%s)\n", names[i], temp))
633 if (!strcasecmp(names[i], temp)) {
634 *numptr = i+low;
635 return ch;
636 }
637 }
638 }
639
640 /* no name list specified, or there is one and our string isn't
641 * in it. either way: if it's all digits, use its magnitude.
642 * otherwise, it's an error.
643 */
644 if (all_digits) {
645 *numptr = atoi(temp);
646 return ch;
647 }
648
649 return EOF;
650 }
651
652
653 static int
set_element(bits,low,high,number)654 set_element(bits, low, high, number)
655 bitstr_t *bits; /* one bit per flag, default=FALSE */
656 int low;
657 int high;
658 int number;
659 {
660 Debug(DPARS|DEXT, ("set_element(?,%d,%d,%d)\n", low, high, number))
661
662 if (number < low || number > high)
663 return EOF;
664
665 bit_set(bits, (number-low));
666 return OK;
667 }
668