1/* vi: set sw=4 ts=4: */
2/*
3 * crond -d[#] -c <crondir> -f -b
4 *
5 * run as root, but NOT setuid root
6 *
7 * Copyright 1994 Matthew Dillon (dillon@apollo.west.oic.com)
8 * (version 2.3.2)
9 * Vladimir Oleynik <dzo@simtreas.ru> (C) 2002
10 *
11 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
12 */
13
14#include <sys/syslog.h>
15#include "libbb.h"
16
17#ifndef CRONTABS
18#define CRONTABS        "/var/spool/cron/crontabs"
19#endif
20#ifndef TMPDIR
21#define TMPDIR          "/var/spool/cron"
22#endif
23#ifndef SENDMAIL
24#define SENDMAIL        "sendmail"
25#endif
26#ifndef SENDMAIL_ARGS
27#define SENDMAIL_ARGS   "-ti", "oem"
28#endif
29#ifndef CRONUPDATE
30#define CRONUPDATE      "cron.update"
31#endif
32#ifndef MAXLINES
33#define MAXLINES        256	/* max lines in non-root crontabs */
34#endif
35
36typedef struct CronFile {
37	struct CronFile *cf_Next;
38	struct CronLine *cf_LineBase;
39	char *cf_User;		/* username                     */
40	int cf_Ready;		/* bool: one or more jobs ready */
41	int cf_Running;		/* bool: one or more jobs running */
42	int cf_Deleted;		/* marked for deletion, ignore  */
43} CronFile;
44
45typedef struct CronLine {
46	struct CronLine *cl_Next;
47	char *cl_Shell;		/* shell command                        */
48	pid_t cl_Pid;		/* running pid, 0, or armed (-1)        */
49	int cl_MailFlag;	/* running pid is for mail              */
50	int cl_MailPos;		/* 'empty file' size                    */
51	char cl_Mins[60];	/* 0-59                                 */
52	char cl_Hrs[24];	/* 0-23                                 */
53	char cl_Days[32];	/* 1-31                                 */
54	char cl_Mons[12];	/* 0-11                                 */
55	char cl_Dow[7];		/* 0-6, beginning sunday                */
56} CronLine;
57
58#define RUN_RANOUT      1
59#define RUN_RUNNING     2
60#define RUN_FAILED      3
61
62#define DaemonUid 0
63
64#if ENABLE_DEBUG_CROND_OPTION
65static unsigned DebugOpt;
66#endif
67
68static unsigned LogLevel = 8;
69static const char *LogFile;
70static const char *CDir = CRONTABS;
71
72static void startlogger(void);
73
74static void CheckUpdates(void);
75static void SynchronizeDir(void);
76static int TestJobs(time_t t1, time_t t2);
77static void RunJobs(void);
78static int CheckJobs(void);
79
80static void RunJob(const char *user, CronLine * line);
81
82#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
83static void EndJob(const char *user, CronLine * line);
84#else
85#define EndJob(user, line)  line->cl_Pid = 0
86#endif
87
88static void DeleteFile(const char *userName);
89
90static CronFile *FileBase;
91
92
93static void crondlog(const char *ctl, ...)
94{
95	va_list va;
96	const char *fmt;
97	int level = (int) (ctl[0] & 0xf);
98	int type = level == 20 ?
99		LOG_ERR : ((ctl[0] & 0100) ? LOG_WARNING : LOG_NOTICE);
100
101
102	va_start(va, ctl);
103	fmt = ctl + 1;
104	if (level >= LogLevel) {
105
106#if ENABLE_DEBUG_CROND_OPTION
107		if (DebugOpt) {
108			vfprintf(stderr, fmt, va);
109		} else
110#endif
111		if (LogFile == 0) {
112			vsyslog(type, fmt, va);
113		} else {
114#if !ENABLE_DEBUG_CROND_OPTION
115			int logfd = open(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
116#else
117			int logfd = open3_or_warn(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
118#endif
119			if (logfd >= 0) {
120				vdprintf(logfd, fmt, va);
121				close(logfd);
122			}
123		}
124	}
125	va_end(va);
126	if (ctl[0] & 0200) {
127		exit(20);
128	}
129}
130
131int crond_main(int ac, char **av);
132int crond_main(int ac, char **av)
133{
134	unsigned opt;
135	char *lopt, *Lopt, *copt;
136	USE_DEBUG_CROND_OPTION(char *dopt;)
137
138	opt_complementary = "f-b:b-f:S-L:L-S" USE_DEBUG_CROND_OPTION(":d-l");
139	opterr = 0;			/* disable getopt 'errors' message. */
140	opt = getopt32(av, "l:L:fbSc:" USE_DEBUG_CROND_OPTION("d:"),
141			&lopt, &Lopt, &copt USE_DEBUG_CROND_OPTION(, &dopt));
142	if (opt & 1) /* -l */
143		LogLevel = xatou(lopt);
144	if (opt & 2) /* -L */
145		if (*Lopt)
146			LogFile = Lopt;
147	if (opt & 32) /* -c */
148		if (*copt)
149			CDir = copt;
150#if ENABLE_DEBUG_CROND_OPTION
151	if (opt & 64) { /* -d */
152		DebugOpt = xatou(dopt);
153		LogLevel = 0;
154	}
155#endif
156
157	/* close stdin and stdout, stderr.
158	 * close unused descriptors -  don't need.
159	 * optional detach from controlling terminal
160	 */
161	if (!(opt & 4))
162		bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, av);
163
164	xchdir(CDir);
165	signal(SIGHUP, SIG_IGN); /* ? original crond dies on HUP... */
166
167	startlogger();	/* need if syslog mode selected */
168
169	/*
170	 * main loop - synchronize to 1 second after the minute, minimum sleep
171	 *             of 1 second.
172	 */
173	crondlog("\011%s " BB_VER " started, log level %d\n",
174			 applet_name, LogLevel);
175
176	SynchronizeDir();
177
178	{
179		time_t t1 = time(NULL);
180		time_t t2;
181		long dt;
182		int rescan = 60;
183		short sleep_time = 60;
184
185		write_pidfile("/var/run/crond.pid");
186		for (;;) {
187			sleep((sleep_time + 1) - (short) (time(NULL) % sleep_time));
188
189			t2 = time(NULL);
190			dt = t2 - t1;
191
192			/*
193			 * The file 'cron.update' is checked to determine new cron
194			 * jobs.  The directory is rescanned once an hour to deal
195			 * with any screwups.
196			 *
197			 * check for disparity.  Disparities over an hour either way
198			 * result in resynchronization.  A reverse-indexed disparity
199			 * less then an hour causes us to effectively sleep until we
200			 * match the original time (i.e. no re-execution of jobs that
201			 * have just been run).  A forward-indexed disparity less then
202			 * an hour causes intermediate jobs to be run, but only once
203			 * in the worst case.
204			 *
205			 * when running jobs, the inequality used is greater but not
206			 * equal to t1, and less then or equal to t2.
207			 */
208
209			if (--rescan == 0) {
210				rescan = 60;
211				SynchronizeDir();
212			}
213			CheckUpdates();
214#if ENABLE_DEBUG_CROND_OPTION
215			if (DebugOpt)
216				crondlog("\005Wakeup dt=%d\n", dt);
217#endif
218			if (dt < -60 * 60 || dt > 60 * 60) {
219				t1 = t2;
220				crondlog("\111time disparity of %d minutes detected\n", dt / 60);
221			} else if (dt > 0) {
222				TestJobs(t1, t2);
223				RunJobs();
224				sleep(5);
225				if (CheckJobs() > 0) {
226					sleep_time = 10;
227				} else {
228					sleep_time = 60;
229				}
230				t1 = t2;
231			}
232		}
233	}
234	return 0; /* not reached */
235}
236
237static int ChangeUser(const char *user)
238{
239	struct passwd *pas;
240	const char *err_msg;
241
242	/*
243	 * Obtain password entry and change privileges
244	 */
245	pas = getpwnam(user);
246	if (pas == 0) {
247		crondlog("\011failed to get uid for %s", user);
248		return -1;
249	}
250	setenv("USER", pas->pw_name, 1);
251	setenv("HOME", pas->pw_dir, 1);
252	setenv("SHELL", DEFAULT_SHELL, 1);
253
254	/*
255	 * Change running state to the user in question
256	 */
257	err_msg = change_identity_e2str(pas);
258	if (err_msg) {
259		crondlog("\011%s for user %s", err_msg, user);
260		return -1;
261	}
262	if (chdir(pas->pw_dir) < 0) {
263		crondlog("\011chdir failed: %s: %m", pas->pw_dir);
264		if (chdir(TMPDIR) < 0) {
265			crondlog("\011chdir failed: %s: %m", TMPDIR);
266			return -1;
267		}
268	}
269	return pas->pw_uid;
270}
271
272static void startlogger(void)
273{
274	if (LogFile == 0) {
275		openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON);
276	}
277#if ENABLE_DEBUG_CROND_OPTION
278	else {				/* test logfile */
279		int logfd;
280
281		logfd = open3_or_warn(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
282		if (logfd >= 0) {
283			close(logfd);
284		}
285	}
286#endif
287}
288
289
290static const char DowAry[] ALIGN1 =
291	"sun""mon""tue""wed""thu""fri""sat"
292	/* "Sun""Mon""Tue""Wed""Thu""Fri""Sat" */
293;
294
295static const char MonAry[] ALIGN1 =
296	"jan""feb""mar""apr""may""jun""jul""aug""sep""oct""nov""dec"
297	/* "Jan""Feb""Mar""Apr""May""Jun""Jul""Aug""Sep""Oct""Nov""Dec" */
298;
299
300static char *ParseField(char *user, char *ary, int modvalue, int off,
301				const char *names, char *ptr)
302/* 'names' is a pointer to a set of 3-char abbreviations */
303{
304	char *base = ptr;
305	int n1 = -1;
306	int n2 = -1;
307
308	if (base == NULL) {
309		return NULL;
310	}
311
312	while (*ptr != ' ' && *ptr != '\t' && *ptr != '\n') {
313		int skip = 0;
314
315		/* Handle numeric digit or symbol or '*' */
316
317		if (*ptr == '*') {
318			n1 = 0;		/* everything will be filled */
319			n2 = modvalue - 1;
320			skip = 1;
321			++ptr;
322		} else if (*ptr >= '0' && *ptr <= '9') {
323			if (n1 < 0) {
324				n1 = strtol(ptr, &ptr, 10) + off;
325			} else {
326				n2 = strtol(ptr, &ptr, 10) + off;
327			}
328			skip = 1;
329		} else if (names) {
330			int i;
331
332			for (i = 0; names[i]; i += 3) {
333				/* was using strncmp before... */
334				if (strncasecmp(ptr, &names[i], 3) == 0) {
335					ptr += 3;
336					if (n1 < 0) {
337						n1 = i / 3;
338					} else {
339						n2 = i / 3;
340					}
341					skip = 1;
342					break;
343				}
344			}
345		}
346
347		/* handle optional range '-' */
348
349		if (skip == 0) {
350			crondlog("\111failed user %s parsing %s\n", user, base);
351			return NULL;
352		}
353		if (*ptr == '-' && n2 < 0) {
354			++ptr;
355			continue;
356		}
357
358		/*
359		 * collapse single-value ranges, handle skipmark, and fill
360		 * in the character array appropriately.
361		 */
362
363		if (n2 < 0) {
364			n2 = n1;
365		}
366		if (*ptr == '/') {
367			skip = strtol(ptr + 1, &ptr, 10);
368		}
369		/*
370		 * fill array, using a failsafe is the easiest way to prevent
371		 * an endless loop
372		 */
373
374		{
375			int s0 = 1;
376			int failsafe = 1024;
377
378			--n1;
379			do {
380				n1 = (n1 + 1) % modvalue;
381
382				if (--s0 == 0) {
383					ary[n1 % modvalue] = 1;
384					s0 = skip;
385				}
386			}
387			while (n1 != n2 && --failsafe);
388
389			if (failsafe == 0) {
390				crondlog("\111failed user %s parsing %s\n", user, base);
391				return NULL;
392			}
393		}
394		if (*ptr != ',') {
395			break;
396		}
397		++ptr;
398		n1 = -1;
399		n2 = -1;
400	}
401
402	if (*ptr != ' ' && *ptr != '\t' && *ptr != '\n') {
403		crondlog("\111failed user %s parsing %s\n", user, base);
404		return NULL;
405	}
406
407	while (*ptr == ' ' || *ptr == '\t' || *ptr == '\n') {
408		++ptr;
409	}
410#if ENABLE_DEBUG_CROND_OPTION
411	if (DebugOpt) {
412		int i;
413
414		for (i = 0; i < modvalue; ++i) {
415			crondlog("\005%d", ary[i]);
416		}
417		crondlog("\005\n");
418	}
419#endif
420
421	return ptr;
422}
423
424static void FixDayDow(CronLine * line)
425{
426	int i;
427	int weekUsed = 0;
428	int daysUsed = 0;
429
430	for (i = 0; i < (int)(ARRAY_SIZE(line->cl_Dow)); ++i) {
431		if (line->cl_Dow[i] == 0) {
432			weekUsed = 1;
433			break;
434		}
435	}
436	for (i = 0; i < (int)(ARRAY_SIZE(line->cl_Days)); ++i) {
437		if (line->cl_Days[i] == 0) {
438			daysUsed = 1;
439			break;
440		}
441	}
442	if (weekUsed && !daysUsed) {
443		memset(line->cl_Days, 0, sizeof(line->cl_Days));
444	}
445	if (daysUsed && !weekUsed) {
446		memset(line->cl_Dow, 0, sizeof(line->cl_Dow));
447	}
448}
449
450
451
452static void SynchronizeFile(const char *fileName)
453{
454	int maxEntries = MAXLINES;
455	int maxLines;
456	char buf[1024];
457
458	if (strcmp(fileName, "root") == 0) {
459		maxEntries = 65535;
460	}
461	maxLines = maxEntries * 10;
462
463	if (fileName) {
464		FILE *fi;
465
466		DeleteFile(fileName);
467
468		fi = fopen(fileName, "r");
469		if (fi != NULL) {
470			struct stat sbuf;
471
472			if (fstat(fileno(fi), &sbuf) == 0 && sbuf.st_uid == DaemonUid) {
473				CronFile *file = xzalloc(sizeof(CronFile));
474				CronLine **pline;
475
476				file->cf_User = strdup(fileName);
477				pline = &file->cf_LineBase;
478
479				while (fgets(buf, sizeof(buf), fi) != NULL && --maxLines) {
480					CronLine line;
481					char *ptr;
482
483					trim(buf);
484					if (buf[0] == 0 || buf[0] == '#') {
485						continue;
486					}
487					if (--maxEntries == 0) {
488						break;
489					}
490					memset(&line, 0, sizeof(line));
491
492#if ENABLE_DEBUG_CROND_OPTION
493					if (DebugOpt) {
494						crondlog("\111User %s Entry %s\n", fileName, buf);
495					}
496#endif
497
498					/* parse date ranges */
499					ptr = ParseField(file->cf_User, line.cl_Mins, 60, 0, NULL, buf);
500					ptr = ParseField(file->cf_User, line.cl_Hrs, 24, 0, NULL, ptr);
501					ptr = ParseField(file->cf_User, line.cl_Days, 32, 0, NULL, ptr);
502					ptr = ParseField(file->cf_User, line.cl_Mons, 12, -1, MonAry, ptr);
503					ptr = ParseField(file->cf_User, line.cl_Dow, 7, 0, DowAry, ptr);
504
505					/* check failure */
506					if (ptr == NULL) {
507						continue;
508					}
509
510					/*
511					 * fix days and dow - if one is not * and the other
512					 * is *, the other is set to 0, and vise-versa
513					 */
514
515					FixDayDow(&line);
516
517					*pline = xzalloc(sizeof(CronLine));
518					**pline = line;
519
520					/* copy command */
521					(*pline)->cl_Shell = strdup(ptr);
522
523#if ENABLE_DEBUG_CROND_OPTION
524					if (DebugOpt) {
525						crondlog("\111    Command %s\n", ptr);
526					}
527#endif
528
529					pline = &((*pline)->cl_Next);
530				}
531				*pline = NULL;
532
533				file->cf_Next = FileBase;
534				FileBase = file;
535
536				if (maxLines == 0 || maxEntries == 0) {
537					crondlog("\111Maximum number of lines reached for user %s\n", fileName);
538				}
539			}
540			fclose(fi);
541		}
542	}
543}
544
545static void CheckUpdates(void)
546{
547	FILE *fi;
548	char buf[256];
549
550	fi = fopen(CRONUPDATE, "r");
551	if (fi != NULL) {
552		remove(CRONUPDATE);
553		while (fgets(buf, sizeof(buf), fi) != NULL) {
554			SynchronizeFile(strtok(buf, " \t\r\n"));
555		}
556		fclose(fi);
557	}
558}
559
560static void SynchronizeDir(void)
561{
562	/* Attempt to delete the database. */
563
564	for (;;) {
565		CronFile *file;
566
567		for (file = FileBase; file && file->cf_Deleted; file = file->cf_Next);
568		if (file == NULL) {
569			break;
570		}
571		DeleteFile(file->cf_User);
572	}
573
574	/*
575	 * Remove cron update file
576	 *
577	 * Re-chdir, in case directory was renamed & deleted, or otherwise
578	 * screwed up.
579	 *
580	 * scan directory and add associated users
581	 */
582
583	remove(CRONUPDATE);
584	if (chdir(CDir) < 0) {
585		crondlog("\311cannot find %s\n", CDir);
586	}
587	{
588		DIR *dir = opendir(".");
589		struct dirent *den;
590
591		if (dir) {
592			while ((den = readdir(dir))) {
593				if (strchr(den->d_name, '.') != NULL) {
594					continue;
595				}
596				if (getpwnam(den->d_name)) {
597					SynchronizeFile(den->d_name);
598				} else {
599					crondlog("\007ignoring %s\n", den->d_name);
600				}
601			}
602			closedir(dir);
603		} else {
604			crondlog("\311cannot open current dir!\n");
605		}
606	}
607}
608
609
610/*
611 *  DeleteFile() - delete user database
612 *
613 *  Note: multiple entries for same user may exist if we were unable to
614 *  completely delete a database due to running processes.
615 */
616
617static void DeleteFile(const char *userName)
618{
619	CronFile **pfile = &FileBase;
620	CronFile *file;
621
622	while ((file = *pfile) != NULL) {
623		if (strcmp(userName, file->cf_User) == 0) {
624			CronLine **pline = &file->cf_LineBase;
625			CronLine *line;
626
627			file->cf_Running = 0;
628			file->cf_Deleted = 1;
629
630			while ((line = *pline) != NULL) {
631				if (line->cl_Pid > 0) {
632					file->cf_Running = 1;
633					pline = &line->cl_Next;
634				} else {
635					*pline = line->cl_Next;
636					free(line->cl_Shell);
637					free(line);
638				}
639			}
640			if (file->cf_Running == 0) {
641				*pfile = file->cf_Next;
642				free(file->cf_User);
643				free(file);
644			} else {
645				pfile = &file->cf_Next;
646			}
647		} else {
648			pfile = &file->cf_Next;
649		}
650	}
651}
652
653/*
654 * TestJobs()
655 *
656 * determine which jobs need to be run.  Under normal conditions, the
657 * period is about a minute (one scan).  Worst case it will be one
658 * hour (60 scans).
659 */
660
661static int TestJobs(time_t t1, time_t t2)
662{
663	int nJobs = 0;
664	time_t t;
665
666	/* Find jobs > t1 and <= t2 */
667
668	for (t = t1 - t1 % 60; t <= t2; t += 60) {
669		if (t > t1) {
670			struct tm *tp = localtime(&t);
671			CronFile *file;
672			CronLine *line;
673
674			for (file = FileBase; file; file = file->cf_Next) {
675#if ENABLE_DEBUG_CROND_OPTION
676				if (DebugOpt)
677					crondlog("\005FILE %s:\n", file->cf_User);
678#endif
679				if (file->cf_Deleted)
680					continue;
681				for (line = file->cf_LineBase; line; line = line->cl_Next) {
682#if ENABLE_DEBUG_CROND_OPTION
683					if (DebugOpt)
684						crondlog("\005    LINE %s\n", line->cl_Shell);
685#endif
686					if (line->cl_Mins[tp->tm_min] && line->cl_Hrs[tp->tm_hour] &&
687						(line->cl_Days[tp->tm_mday] || line->cl_Dow[tp->tm_wday])
688						&& line->cl_Mons[tp->tm_mon]) {
689#if ENABLE_DEBUG_CROND_OPTION
690						if (DebugOpt) {
691							crondlog("\005    JobToDo: %d %s\n",
692								line->cl_Pid, line->cl_Shell);
693						}
694#endif
695						if (line->cl_Pid > 0) {
696							crondlog("\010    process already running: %s %s\n",
697								file->cf_User, line->cl_Shell);
698						} else if (line->cl_Pid == 0) {
699							line->cl_Pid = -1;
700							file->cf_Ready = 1;
701							++nJobs;
702						}
703					}
704				}
705			}
706		}
707	}
708	return nJobs;
709}
710
711static void RunJobs(void)
712{
713	CronFile *file;
714	CronLine *line;
715
716	for (file = FileBase; file; file = file->cf_Next) {
717		if (file->cf_Ready) {
718			file->cf_Ready = 0;
719
720			for (line = file->cf_LineBase; line; line = line->cl_Next) {
721				if (line->cl_Pid < 0) {
722
723					RunJob(file->cf_User, line);
724
725					crondlog("\010USER %s pid %3d cmd %s\n",
726						file->cf_User, line->cl_Pid, line->cl_Shell);
727					if (line->cl_Pid < 0) {
728						file->cf_Ready = 1;
729					}
730					else if (line->cl_Pid > 0) {
731						file->cf_Running = 1;
732					}
733				}
734			}
735		}
736	}
737}
738
739/*
740 * CheckJobs() - check for job completion
741 *
742 * Check for job completion, return number of jobs still running after
743 * all done.
744 */
745
746static int CheckJobs(void)
747{
748	CronFile *file;
749	CronLine *line;
750	int nStillRunning = 0;
751
752	for (file = FileBase; file; file = file->cf_Next) {
753		if (file->cf_Running) {
754			file->cf_Running = 0;
755
756			for (line = file->cf_LineBase; line; line = line->cl_Next) {
757				if (line->cl_Pid > 0) {
758					int status;
759					int r = wait4(line->cl_Pid, &status, WNOHANG, NULL);
760
761					if (r < 0 || r == line->cl_Pid) {
762						EndJob(file->cf_User, line);
763						if (line->cl_Pid) {
764							file->cf_Running = 1;
765						}
766					} else if (r == 0) {
767						file->cf_Running = 1;
768					}
769				}
770			}
771		}
772		nStillRunning += file->cf_Running;
773	}
774	return nStillRunning;
775}
776
777
778#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
779static void
780ForkJob(const char *user, CronLine * line, int mailFd,
781		const char *prog, const char *cmd, const char *arg, const char *mailf)
782{
783	/* Fork as the user in question and run program */
784	pid_t pid = fork();
785
786	line->cl_Pid = pid;
787	if (pid == 0) {
788		/* CHILD */
789
790		/* Change running state to the user in question */
791
792		if (ChangeUser(user) < 0) {
793			exit(0);
794		}
795#if ENABLE_DEBUG_CROND_OPTION
796		if (DebugOpt) {
797			crondlog("\005Child Running %s\n", prog);
798		}
799#endif
800
801		if (mailFd >= 0) {
802			dup2(mailFd, mailf != NULL);
803			dup2((mailf ? mailFd : 1), 2);
804			close(mailFd);
805		}
806		execl(prog, prog, cmd, arg, NULL);
807		crondlog("\024cannot exec, user %s cmd %s %s %s\n", user, prog, cmd, arg);
808		if (mailf) {
809			fdprintf(1, "Exec failed: %s -c %s\n", prog, arg);
810		}
811		exit(0);
812	} else if (pid < 0) {
813		/* FORK FAILED */
814		crondlog("\024cannot fork, user %s\n", user);
815		line->cl_Pid = 0;
816		if (mailf) {
817			remove(mailf);
818		}
819	} else if (mailf) {
820		/* PARENT, FORK SUCCESS
821		 * rename mail-file based on pid of process
822		 */
823		char mailFile2[128];
824
825		snprintf(mailFile2, sizeof(mailFile2), TMPDIR "/cron.%s.%d", user, pid);
826		rename(mailf, mailFile2);
827	}
828	/*
829	 * Close the mail file descriptor.. we can't just leave it open in
830	 * a structure, closing it later, because we might run out of descriptors
831	 */
832
833	if (mailFd >= 0) {
834		close(mailFd);
835	}
836}
837
838static void RunJob(const char *user, CronLine * line)
839{
840	char mailFile[128];
841	int mailFd;
842
843	line->cl_Pid = 0;
844	line->cl_MailFlag = 0;
845
846	/* open mail file - owner root so nobody can screw with it. */
847
848	snprintf(mailFile, sizeof(mailFile), TMPDIR "/cron.%s.%d", user, getpid());
849	mailFd = open(mailFile, O_CREAT | O_TRUNC | O_WRONLY | O_EXCL | O_APPEND, 0600);
850
851	if (mailFd >= 0) {
852		line->cl_MailFlag = 1;
853		fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", user,
854			line->cl_Shell);
855		line->cl_MailPos = lseek(mailFd, 0, SEEK_CUR);
856	} else {
857		crondlog("\024cannot create mail file user %s file %s, output to /dev/null\n", user, mailFile);
858	}
859
860	ForkJob(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_Shell, mailFile);
861}
862
863/*
864 * EndJob - called when job terminates and when mail terminates
865 */
866
867static void EndJob(const char *user, CronLine * line)
868{
869	int mailFd;
870	char mailFile[128];
871	struct stat sbuf;
872
873	/* No job */
874
875	if (line->cl_Pid <= 0) {
876		line->cl_Pid = 0;
877		return;
878	}
879
880	/*
881	 * End of job and no mail file
882	 * End of sendmail job
883	 */
884
885	snprintf(mailFile, sizeof(mailFile), TMPDIR "/cron.%s.%d", user, line->cl_Pid);
886	line->cl_Pid = 0;
887
888	if (line->cl_MailFlag != 1) {
889		return;
890	}
891	line->cl_MailFlag = 0;
892
893	/*
894	 * End of primary job - check for mail file.  If size has increased and
895	 * the file is still valid, we sendmail it.
896	 */
897
898	mailFd = open(mailFile, O_RDONLY);
899	remove(mailFile);
900	if (mailFd < 0) {
901		return;
902	}
903
904	if (fstat(mailFd, &sbuf) < 0 || sbuf.st_uid != DaemonUid
905	 || sbuf.st_nlink != 0 || sbuf.st_size == line->cl_MailPos
906	 || !S_ISREG(sbuf.st_mode)
907	) {
908		close(mailFd);
909		return;
910	}
911	ForkJob(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL);
912}
913#else
914/* crond without sendmail */
915
916static void RunJob(const char *user, CronLine * line)
917{
918	/* Fork as the user in question and run program */
919	pid_t pid = fork();
920
921	if (pid == 0) {
922		/* CHILD */
923
924		/* Change running state to the user in question */
925
926		if (ChangeUser(user) < 0) {
927			exit(0);
928		}
929#if ENABLE_DEBUG_CROND_OPTION
930		if (DebugOpt) {
931			crondlog("\005Child Running %s\n", DEFAULT_SHELL);
932		}
933#endif
934
935		execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_Shell, NULL);
936		crondlog("\024cannot exec, user %s cmd %s -c %s\n", user,
937				 DEFAULT_SHELL, line->cl_Shell);
938		exit(0);
939	} else if (pid < 0) {
940		/* FORK FAILED */
941		crondlog("\024cannot, user %s\n", user);
942		pid = 0;
943	}
944	line->cl_Pid = pid;
945}
946#endif /* ENABLE_FEATURE_CROND_CALL_SENDMAIL */
947