| /* vi: set sw=4 ts=4: */ |
| /* |
| * crond -d[#] -c <crondir> -f -b |
| * |
| * run as root, but NOT setuid root |
| * |
| * Copyright 1994 Matthew Dillon (dillon@apollo.west.oic.com) |
| * (version 2.3.2) |
| * Vladimir Oleynik <dzo@simtreas.ru> (C) 2002 |
| * |
| * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. |
| */ |
| |
| #include "libbb.h" |
| #include <syslog.h> |
| |
| /* glibc frees previous setenv'ed value when we do next setenv() |
| * of the same variable. uclibc does not do this! */ |
| #if (defined(__GLIBC__) && !defined(__UCLIBC__)) /* || OTHER_SAFE_LIBC... */ |
| #define SETENV_LEAKS 0 |
| #else |
| #define SETENV_LEAKS 1 |
| #endif |
| |
| |
| #ifndef CRONTABS |
| #define CRONTABS "/var/spool/cron/crontabs" |
| #endif |
| #ifndef TMPDIR |
| #define TMPDIR "/var/spool/cron" |
| #endif |
| #ifndef SENDMAIL |
| #define SENDMAIL "sendmail" |
| #endif |
| #ifndef SENDMAIL_ARGS |
| #define SENDMAIL_ARGS "-ti", "oem" |
| #endif |
| #ifndef CRONUPDATE |
| #define CRONUPDATE "cron.update" |
| #endif |
| #ifndef MAXLINES |
| #define MAXLINES 256 /* max lines in non-root crontabs */ |
| #endif |
| |
| |
| typedef struct CronFile { |
| struct CronFile *cf_Next; |
| struct CronLine *cf_LineBase; |
| char *cf_User; /* username */ |
| smallint cf_Ready; /* bool: one or more jobs ready */ |
| smallint cf_Running; /* bool: one or more jobs running */ |
| smallint cf_Deleted; /* marked for deletion, ignore */ |
| } CronFile; |
| |
| typedef struct CronLine { |
| struct CronLine *cl_Next; |
| char *cl_Shell; /* shell command */ |
| pid_t cl_Pid; /* running pid, 0, or armed (-1) */ |
| #if ENABLE_FEATURE_CROND_CALL_SENDMAIL |
| int cl_MailPos; /* 'empty file' size */ |
| smallint cl_MailFlag; /* running pid is for mail */ |
| #endif |
| /* ordered by size, not in natural order. makes code smaller: */ |
| char cl_Dow[7]; /* 0-6, beginning sunday */ |
| char cl_Mons[12]; /* 0-11 */ |
| char cl_Hrs[24]; /* 0-23 */ |
| char cl_Days[32]; /* 1-31 */ |
| char cl_Mins[60]; /* 0-59 */ |
| } CronLine; |
| |
| |
| #define DaemonUid 0 |
| |
| |
| enum { |
| OPT_l = (1 << 0), |
| OPT_L = (1 << 1), |
| OPT_f = (1 << 2), |
| OPT_b = (1 << 3), |
| OPT_S = (1 << 4), |
| OPT_c = (1 << 5), |
| OPT_d = (1 << 6) * ENABLE_DEBUG_CROND_OPTION, |
| }; |
| #if ENABLE_DEBUG_CROND_OPTION |
| #define DebugOpt (option_mask32 & OPT_d) |
| #else |
| #define DebugOpt 0 |
| #endif |
| |
| |
| struct globals { |
| unsigned LogLevel; /* = 8; */ |
| const char *LogFile; |
| const char *CDir; /* = CRONTABS; */ |
| CronFile *FileBase; |
| #if SETENV_LEAKS |
| char *env_var_user; |
| char *env_var_home; |
| #endif |
| }; |
| #define G (*(struct globals*)&bb_common_bufsiz1) |
| #define LogLevel (G.LogLevel ) |
| #define LogFile (G.LogFile ) |
| #define CDir (G.CDir ) |
| #define FileBase (G.FileBase ) |
| #define env_var_user (G.env_var_user ) |
| #define env_var_home (G.env_var_home ) |
| #define INIT_G() do { \ |
| LogLevel = 8; \ |
| CDir = CRONTABS; \ |
| } while (0) |
| |
| |
| static void CheckUpdates(void); |
| static void SynchronizeDir(void); |
| static int TestJobs(time_t t1, time_t t2); |
| static void RunJobs(void); |
| static int CheckJobs(void); |
| static void RunJob(const char *user, CronLine *line); |
| #if ENABLE_FEATURE_CROND_CALL_SENDMAIL |
| static void EndJob(const char *user, CronLine *line); |
| #else |
| #define EndJob(user, line) ((line)->cl_Pid = 0) |
| #endif |
| static void DeleteFile(const char *userName); |
| |
| |
| #define LVL5 "\x05" |
| #define LVL7 "\x07" |
| #define LVL8 "\x08" |
| #define LVL9 "\x09" |
| #define WARN9 "\x49" |
| #define DIE9 "\xc9" |
| /* level >= 20 is "error" */ |
| #define ERR20 "\x14" |
| |
| static void crondlog(const char *ctl, ...) |
| { |
| va_list va; |
| int level = (ctl[0] & 0x1f); |
| |
| va_start(va, ctl); |
| if (level >= LogLevel) { |
| /* Debug mode: all to (non-redirected) stderr, */ |
| /* Syslog mode: all to syslog (logmode = LOGMODE_SYSLOG), */ |
| if (!DebugOpt && LogFile) { |
| /* Otherwise (log to file): we reopen log file at every write: */ |
| int logfd = open3_or_warn(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600); |
| if (logfd >= 0) |
| xmove_fd(logfd, STDERR_FILENO); |
| } |
| // TODO: ERR -> error, WARN -> warning, LVL -> info |
| bb_verror_msg(ctl + 1, va, /* strerr: */ NULL); |
| } |
| va_end(va); |
| if (ctl[0] & 0x80) |
| exit(20); |
| } |
| |
| int crond_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int crond_main(int argc ATTRIBUTE_UNUSED, char **argv) |
| { |
| unsigned opt; |
| |
| INIT_G(); |
| |
| /* "-b after -f is ignored", and so on for every pair a-b */ |
| opt_complementary = "f-b:b-f:S-L:L-S" USE_DEBUG_CROND_OPTION(":d-l") |
| ":l+:d+"; /* -l and -d have numeric param */ |
| opt = getopt32(argv, "l:L:fbSc:" USE_DEBUG_CROND_OPTION("d:"), |
| &LogLevel, &LogFile, &CDir |
| USE_DEBUG_CROND_OPTION(,&LogLevel)); |
| /* both -d N and -l N set the same variable: LogLevel */ |
| |
| if (!(opt & OPT_f)) { |
| /* close stdin, stdout, stderr. |
| * close unused descriptors - don't need them. */ |
| bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv); |
| } |
| |
| if (!DebugOpt && LogFile == NULL) { |
| /* logging to syslog */ |
| openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON); |
| logmode = LOGMODE_SYSLOG; |
| } |
| |
| xchdir(CDir); |
| //signal(SIGHUP, SIG_IGN); /* ? original crond dies on HUP... */ |
| setenv("SHELL", DEFAULT_SHELL, 1); /* once, for all future children */ |
| crondlog(LVL9 "crond (busybox "BB_VER") started, log level %d", LogLevel); |
| SynchronizeDir(); |
| |
| /* main loop - synchronize to 1 second after the minute, minimum sleep |
| * of 1 second. */ |
| { |
| time_t t1 = time(NULL); |
| time_t t2; |
| long dt; |
| int rescan = 60; |
| int sleep_time = 60; |
| |
| write_pidfile("/var/run/crond.pid"); |
| for (;;) { |
| sleep((sleep_time + 1) - (time(NULL) % sleep_time)); |
| |
| t2 = time(NULL); |
| dt = (long)t2 - (long)t1; |
| |
| /* |
| * The file 'cron.update' is checked to determine new cron |
| * jobs. The directory is rescanned once an hour to deal |
| * with any screwups. |
| * |
| * check for disparity. Disparities over an hour either way |
| * result in resynchronization. A reverse-indexed disparity |
| * less then an hour causes us to effectively sleep until we |
| * match the original time (i.e. no re-execution of jobs that |
| * have just been run). A forward-indexed disparity less then |
| * an hour causes intermediate jobs to be run, but only once |
| * in the worst case. |
| * |
| * when running jobs, the inequality used is greater but not |
| * equal to t1, and less then or equal to t2. |
| */ |
| if (--rescan == 0) { |
| rescan = 60; |
| SynchronizeDir(); |
| } |
| CheckUpdates(); |
| if (DebugOpt) |
| crondlog(LVL5 "wakeup dt=%ld", dt); |
| if (dt < -60 * 60 || dt > 60 * 60) { |
| crondlog(WARN9 "time disparity of %d minutes detected", dt / 60); |
| } else if (dt > 0) { |
| TestJobs(t1, t2); |
| RunJobs(); |
| sleep(5); |
| if (CheckJobs() > 0) { |
| sleep_time = 10; |
| } else { |
| sleep_time = 60; |
| } |
| } |
| t1 = t2; |
| } |
| } |
| return 0; /* not reached */ |
| } |
| |
| #if SETENV_LEAKS |
| /* We set environment *before* vfork (because we want to use vfork), |
| * so we cannot use setenv() - repeated calls to setenv() may leak memory! |
| * Using putenv(), and freeing memory after unsetenv() won't leak */ |
| static void safe_setenv4(char **pvar_val, const char *var, const char *val /*, int len*/) |
| { |
| const int len = 4; /* both var names are 4 char long */ |
| char *var_val = *pvar_val; |
| |
| if (var_val) { |
| var_val[len] = '\0'; /* nuke '=' */ |
| unsetenv(var_val); |
| free(var_val); |
| } |
| *pvar_val = xasprintf("%s=%s", var, val); |
| putenv(*pvar_val); |
| } |
| #endif |
| |
| static void SetEnv(struct passwd *pas) |
| { |
| #if SETENV_LEAKS |
| safe_setenv4(&env_var_user, "USER", pas->pw_name); |
| safe_setenv4(&env_var_home, "HOME", pas->pw_dir); |
| /* if we want to set user's shell instead: */ |
| /*safe_setenv(env_var_user, "SHELL", pas->pw_shell, 5);*/ |
| #else |
| setenv("USER", pas->pw_name, 1); |
| setenv("HOME", pas->pw_dir, 1); |
| #endif |
| /* currently, we use constant one: */ |
| /*setenv("SHELL", DEFAULT_SHELL, 1); - done earlier */ |
| } |
| |
| static void ChangeUser(struct passwd *pas) |
| { |
| /* careful: we're after vfork! */ |
| change_identity(pas); /* - initgroups, setgid, setuid */ |
| if (chdir(pas->pw_dir) < 0) { |
| crondlog(LVL9 "can't chdir(%s)", pas->pw_dir); |
| if (chdir(TMPDIR) < 0) { |
| crondlog(DIE9 "can't chdir(%s)", TMPDIR); /* exits */ |
| } |
| } |
| } |
| |
| static const char DowAry[] ALIGN1 = |
| "sun""mon""tue""wed""thu""fri""sat" |
| /* "Sun""Mon""Tue""Wed""Thu""Fri""Sat" */ |
| ; |
| |
| static const char MonAry[] ALIGN1 = |
| "jan""feb""mar""apr""may""jun""jul""aug""sep""oct""nov""dec" |
| /* "Jan""Feb""Mar""Apr""May""Jun""Jul""Aug""Sep""Oct""Nov""Dec" */ |
| ; |
| |
| static char *ParseField(char *user, char *ary, int modvalue, int off, |
| const char *names, char *ptr) |
| /* 'names' is a pointer to a set of 3-char abbreviations */ |
| { |
| char *base = ptr; |
| int n1 = -1; |
| int n2 = -1; |
| |
| if (base == NULL) { |
| return NULL; |
| } |
| |
| while (!isspace(*ptr)) { |
| int skip = 0; |
| |
| /* Handle numeric digit or symbol or '*' */ |
| if (*ptr == '*') { |
| n1 = 0; /* everything will be filled */ |
| n2 = modvalue - 1; |
| skip = 1; |
| ++ptr; |
| } else if (isdigit(*ptr)) { |
| if (n1 < 0) { |
| n1 = strtol(ptr, &ptr, 10) + off; |
| } else { |
| n2 = strtol(ptr, &ptr, 10) + off; |
| } |
| skip = 1; |
| } else if (names) { |
| int i; |
| |
| for (i = 0; names[i]; i += 3) { |
| /* was using strncmp before... */ |
| if (strncasecmp(ptr, &names[i], 3) == 0) { |
| ptr += 3; |
| if (n1 < 0) { |
| n1 = i / 3; |
| } else { |
| n2 = i / 3; |
| } |
| skip = 1; |
| break; |
| } |
| } |
| } |
| |
| /* handle optional range '-' */ |
| if (skip == 0) { |
| crondlog(WARN9 "user %s: parse error at %s", user, base); |
| return NULL; |
| } |
| if (*ptr == '-' && n2 < 0) { |
| ++ptr; |
| continue; |
| } |
| |
| /* |
| * collapse single-value ranges, handle skipmark, and fill |
| * in the character array appropriately. |
| */ |
| if (n2 < 0) { |
| n2 = n1; |
| } |
| if (*ptr == '/') { |
| skip = strtol(ptr + 1, &ptr, 10); |
| } |
| |
| /* |
| * fill array, using a failsafe is the easiest way to prevent |
| * an endless loop |
| */ |
| { |
| int s0 = 1; |
| int failsafe = 1024; |
| |
| --n1; |
| do { |
| n1 = (n1 + 1) % modvalue; |
| |
| if (--s0 == 0) { |
| ary[n1 % modvalue] = 1; |
| s0 = skip; |
| } |
| if (--failsafe == 0) { |
| crondlog(WARN9 "user %s: parse error at %s", user, base); |
| return NULL; |
| } |
| } while (n1 != n2); |
| |
| } |
| if (*ptr != ',') { |
| break; |
| } |
| ++ptr; |
| n1 = -1; |
| n2 = -1; |
| } |
| |
| if (!isspace(*ptr)) { |
| crondlog(WARN9 "user %s: parse error at %s", user, base); |
| return NULL; |
| } |
| |
| if (DebugOpt && (LogLevel <= 5)) { /* like LVL5 */ |
| /* can't use crondlog, it inserts '\n' */ |
| int i; |
| for (i = 0; i < modvalue; ++i) |
| fprintf(stderr, "%d", (unsigned char)ary[i]); |
| fputc('\n', stderr); |
| } |
| return skip_whitespace(ptr); |
| } |
| |
| static void FixDayDow(CronLine *line) |
| { |
| int i; |
| int weekUsed = 0; |
| int daysUsed = 0; |
| |
| for (i = 0; i < ARRAY_SIZE(line->cl_Dow); ++i) { |
| if (line->cl_Dow[i] == 0) { |
| weekUsed = 1; |
| break; |
| } |
| } |
| for (i = 0; i < ARRAY_SIZE(line->cl_Days); ++i) { |
| if (line->cl_Days[i] == 0) { |
| daysUsed = 1; |
| break; |
| } |
| } |
| if (weekUsed != daysUsed) { |
| if (weekUsed) |
| memset(line->cl_Days, 0, sizeof(line->cl_Days)); |
| else /* daysUsed */ |
| memset(line->cl_Dow, 0, sizeof(line->cl_Dow)); |
| } |
| } |
| |
| static void SynchronizeFile(const char *fileName) |
| { |
| FILE *fi; |
| struct stat sbuf; |
| int maxEntries; |
| int maxLines; |
| char buf[1024]; |
| |
| if (!fileName) |
| return; |
| |
| DeleteFile(fileName); |
| fi = fopen(fileName, "r"); |
| if (!fi) |
| return; |
| |
| maxEntries = MAXLINES; |
| if (strcmp(fileName, "root") == 0) { |
| maxEntries = 65535; |
| } |
| maxLines = maxEntries * 10; |
| |
| if (fstat(fileno(fi), &sbuf) == 0 && sbuf.st_uid == DaemonUid) { |
| CronFile *file = xzalloc(sizeof(CronFile)); |
| CronLine **pline; |
| |
| file->cf_User = xstrdup(fileName); |
| pline = &file->cf_LineBase; |
| |
| while (fgets(buf, sizeof(buf), fi) != NULL && --maxLines) { |
| CronLine *line; |
| char *ptr; |
| |
| trim(buf); |
| if (buf[0] == '\0' || buf[0] == '#') { |
| continue; |
| } |
| if (--maxEntries == 0) { |
| break; |
| } |
| if (DebugOpt) { |
| crondlog(LVL5 "user:%s entry:%s", fileName, buf); |
| } |
| *pline = line = xzalloc(sizeof(CronLine)); |
| /* parse date ranges */ |
| ptr = ParseField(file->cf_User, line->cl_Mins, 60, 0, NULL, buf); |
| ptr = ParseField(file->cf_User, line->cl_Hrs, 24, 0, NULL, ptr); |
| ptr = ParseField(file->cf_User, line->cl_Days, 32, 0, NULL, ptr); |
| ptr = ParseField(file->cf_User, line->cl_Mons, 12, -1, MonAry, ptr); |
| ptr = ParseField(file->cf_User, line->cl_Dow, 7, 0, DowAry, ptr); |
| /* check failure */ |
| if (ptr == NULL) { |
| free(line); |
| continue; |
| } |
| /* |
| * fix days and dow - if one is not * and the other |
| * is *, the other is set to 0, and vise-versa |
| */ |
| FixDayDow(line); |
| /* copy command */ |
| line->cl_Shell = xstrdup(ptr); |
| if (DebugOpt) { |
| crondlog(LVL5 " command:%s", ptr); |
| } |
| pline = &line->cl_Next; |
| } |
| *pline = NULL; |
| |
| file->cf_Next = FileBase; |
| FileBase = file; |
| |
| if (maxLines == 0 || maxEntries == 0) { |
| crondlog(WARN9 "maximum number of lines reached for user %s", fileName); |
| } |
| } |
| fclose(fi); |
| } |
| |
| static void CheckUpdates(void) |
| { |
| FILE *fi; |
| char buf[256]; |
| |
| fi = fopen(CRONUPDATE, "r"); |
| if (fi != NULL) { |
| unlink(CRONUPDATE); |
| while (fgets(buf, sizeof(buf), fi) != NULL) { |
| /* use first word only */ |
| SynchronizeFile(strtok(buf, " \t\r\n")); |
| } |
| fclose(fi); |
| } |
| } |
| |
| static void SynchronizeDir(void) |
| { |
| CronFile *file; |
| /* Attempt to delete the database. */ |
| again: |
| for (file = FileBase; file; file = file->cf_Next) { |
| if (!file->cf_Deleted) { |
| DeleteFile(file->cf_User); |
| goto again; |
| } |
| } |
| |
| /* |
| * Remove cron update file |
| * |
| * Re-chdir, in case directory was renamed & deleted, or otherwise |
| * screwed up. |
| * |
| * scan directory and add associated users |
| */ |
| unlink(CRONUPDATE); |
| if (chdir(CDir) < 0) { |
| crondlog(DIE9 "can't chdir(%s)", CDir); |
| } |
| { |
| DIR *dir = opendir("."); |
| struct dirent *den; |
| |
| if (!dir) |
| crondlog(DIE9 "can't chdir(%s)", "."); /* exits */ |
| while ((den = readdir(dir))) { |
| if (strchr(den->d_name, '.') != NULL) { |
| continue; |
| } |
| if (getpwnam(den->d_name)) { |
| SynchronizeFile(den->d_name); |
| } else { |
| crondlog(LVL7 "ignoring %s", den->d_name); |
| } |
| } |
| closedir(dir); |
| } |
| } |
| |
| /* |
| * DeleteFile() - delete user database |
| * |
| * Note: multiple entries for same user may exist if we were unable to |
| * completely delete a database due to running processes. |
| */ |
| static void DeleteFile(const char *userName) |
| { |
| CronFile **pfile = &FileBase; |
| CronFile *file; |
| |
| while ((file = *pfile) != NULL) { |
| if (strcmp(userName, file->cf_User) == 0) { |
| CronLine **pline = &file->cf_LineBase; |
| CronLine *line; |
| |
| file->cf_Running = 0; |
| file->cf_Deleted = 1; |
| |
| while ((line = *pline) != NULL) { |
| if (line->cl_Pid > 0) { |
| file->cf_Running = 1; |
| pline = &line->cl_Next; |
| } else { |
| *pline = line->cl_Next; |
| free(line->cl_Shell); |
| free(line); |
| } |
| } |
| if (file->cf_Running == 0) { |
| *pfile = file->cf_Next; |
| free(file->cf_User); |
| free(file); |
| } else { |
| pfile = &file->cf_Next; |
| } |
| } else { |
| pfile = &file->cf_Next; |
| } |
| } |
| } |
| |
| /* |
| * TestJobs() |
| * |
| * determine which jobs need to be run. Under normal conditions, the |
| * period is about a minute (one scan). Worst case it will be one |
| * hour (60 scans). |
| */ |
| static int TestJobs(time_t t1, time_t t2) |
| { |
| int nJobs = 0; |
| time_t t; |
| |
| /* Find jobs > t1 and <= t2 */ |
| |
| for (t = t1 - t1 % 60; t <= t2; t += 60) { |
| struct tm *tp; |
| CronFile *file; |
| CronLine *line; |
| |
| if (t <= t1) |
| continue; |
| |
| tp = localtime(&t); |
| for (file = FileBase; file; file = file->cf_Next) { |
| if (DebugOpt) |
| crondlog(LVL5 "file %s:", file->cf_User); |
| if (file->cf_Deleted) |
| continue; |
| for (line = file->cf_LineBase; line; line = line->cl_Next) { |
| if (DebugOpt) |
| crondlog(LVL5 " line %s", line->cl_Shell); |
| if (line->cl_Mins[tp->tm_min] && line->cl_Hrs[tp->tm_hour] |
| && (line->cl_Days[tp->tm_mday] || line->cl_Dow[tp->tm_wday]) |
| && line->cl_Mons[tp->tm_mon] |
| ) { |
| if (DebugOpt) { |
| crondlog(LVL5 " job: %d %s", |
| (int)line->cl_Pid, line->cl_Shell); |
| } |
| if (line->cl_Pid > 0) { |
| crondlog(LVL8 "user %s: process already running: %s", |
| file->cf_User, line->cl_Shell); |
| } else if (line->cl_Pid == 0) { |
| line->cl_Pid = -1; |
| file->cf_Ready = 1; |
| ++nJobs; |
| } |
| } |
| } |
| } |
| } |
| return nJobs; |
| } |
| |
| static void RunJobs(void) |
| { |
| CronFile *file; |
| CronLine *line; |
| |
| for (file = FileBase; file; file = file->cf_Next) { |
| if (!file->cf_Ready) |
| continue; |
| |
| file->cf_Ready = 0; |
| for (line = file->cf_LineBase; line; line = line->cl_Next) { |
| if (line->cl_Pid >= 0) |
| continue; |
| |
| RunJob(file->cf_User, line); |
| crondlog(LVL8 "USER %s pid %3d cmd %s", |
| file->cf_User, (int)line->cl_Pid, line->cl_Shell); |
| if (line->cl_Pid < 0) { |
| file->cf_Ready = 1; |
| } else if (line->cl_Pid > 0) { |
| file->cf_Running = 1; |
| } |
| } |
| } |
| } |
| |
| /* |
| * CheckJobs() - check for job completion |
| * |
| * Check for job completion, return number of jobs still running after |
| * all done. |
| */ |
| static int CheckJobs(void) |
| { |
| CronFile *file; |
| CronLine *line; |
| int nStillRunning = 0; |
| |
| for (file = FileBase; file; file = file->cf_Next) { |
| if (file->cf_Running) { |
| file->cf_Running = 0; |
| |
| for (line = file->cf_LineBase; line; line = line->cl_Next) { |
| int status, r; |
| if (line->cl_Pid <= 0) |
| continue; |
| |
| r = waitpid(line->cl_Pid, &status, WNOHANG); |
| if (r < 0 || r == line->cl_Pid) { |
| EndJob(file->cf_User, line); |
| if (line->cl_Pid) { |
| file->cf_Running = 1; |
| } |
| } else if (r == 0) { |
| file->cf_Running = 1; |
| } |
| } |
| } |
| nStillRunning += file->cf_Running; |
| } |
| return nStillRunning; |
| } |
| |
| #if ENABLE_FEATURE_CROND_CALL_SENDMAIL |
| |
| // TODO: sendmail should be _run-time_ option, not compile-time! |
| |
| static void |
| ForkJob(const char *user, CronLine *line, int mailFd, |
| const char *prog, const char *cmd, const char *arg, |
| const char *mail_filename) |
| { |
| struct passwd *pas; |
| pid_t pid; |
| |
| /* prepare things before vfork */ |
| pas = getpwnam(user); |
| if (!pas) { |
| crondlog(LVL9 "can't get uid for %s", user); |
| goto err; |
| } |
| SetEnv(pas); |
| |
| pid = vfork(); |
| if (pid == 0) { |
| /* CHILD */ |
| /* change running state to the user in question */ |
| ChangeUser(pas); |
| if (DebugOpt) { |
| crondlog(LVL5 "child running %s", prog); |
| } |
| if (mailFd >= 0) { |
| xmove_fd(mailFd, mail_filename ? 1 : 0); |
| dup2(1, 2); |
| } |
| execl(prog, prog, cmd, arg, NULL); |
| crondlog(ERR20 "can't exec, user %s cmd %s %s %s", user, prog, cmd, arg); |
| if (mail_filename) { |
| fdprintf(1, "Exec failed: %s -c %s\n", prog, arg); |
| } |
| _exit(0); |
| } |
| |
| line->cl_Pid = pid; |
| if (pid < 0) { |
| /* FORK FAILED */ |
| crondlog(ERR20 "can't vfork"); |
| err: |
| line->cl_Pid = 0; |
| if (mail_filename) { |
| unlink(mail_filename); |
| } |
| } else if (mail_filename) { |
| /* PARENT, FORK SUCCESS |
| * rename mail-file based on pid of process |
| */ |
| char mailFile2[128]; |
| |
| snprintf(mailFile2, sizeof(mailFile2), "%s/cron.%s.%d", TMPDIR, user, pid); |
| rename(mail_filename, mailFile2); // TODO: xrename? |
| } |
| |
| /* |
| * Close the mail file descriptor.. we can't just leave it open in |
| * a structure, closing it later, because we might run out of descriptors |
| */ |
| if (mailFd >= 0) { |
| close(mailFd); |
| } |
| } |
| |
| static void RunJob(const char *user, CronLine *line) |
| { |
| char mailFile[128]; |
| int mailFd; |
| |
| line->cl_Pid = 0; |
| line->cl_MailFlag = 0; |
| |
| /* open mail file - owner root so nobody can screw with it. */ |
| snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, getpid()); |
| mailFd = open(mailFile, O_CREAT | O_TRUNC | O_WRONLY | O_EXCL | O_APPEND, 0600); |
| |
| if (mailFd >= 0) { |
| line->cl_MailFlag = 1; |
| fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", user, |
| line->cl_Shell); |
| line->cl_MailPos = lseek(mailFd, 0, SEEK_CUR); |
| } else { |
| crondlog(ERR20 "cannot create mail file %s for user %s, " |
| "discarding output", mailFile, user); |
| } |
| |
| ForkJob(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_Shell, mailFile); |
| } |
| |
| /* |
| * EndJob - called when job terminates and when mail terminates |
| */ |
| static void EndJob(const char *user, CronLine *line) |
| { |
| int mailFd; |
| char mailFile[128]; |
| struct stat sbuf; |
| |
| /* No job */ |
| if (line->cl_Pid <= 0) { |
| line->cl_Pid = 0; |
| return; |
| } |
| |
| /* |
| * End of job and no mail file |
| * End of sendmail job |
| */ |
| snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, line->cl_Pid); |
| line->cl_Pid = 0; |
| |
| if (line->cl_MailFlag == 0) { |
| return; |
| } |
| line->cl_MailFlag = 0; |
| |
| /* |
| * End of primary job - check for mail file. If size has increased and |
| * the file is still valid, we sendmail it. |
| */ |
| mailFd = open(mailFile, O_RDONLY); |
| unlink(mailFile); |
| if (mailFd < 0) { |
| return; |
| } |
| |
| if (fstat(mailFd, &sbuf) < 0 || sbuf.st_uid != DaemonUid |
| || sbuf.st_nlink != 0 || sbuf.st_size == line->cl_MailPos |
| || !S_ISREG(sbuf.st_mode) |
| ) { |
| close(mailFd); |
| return; |
| } |
| ForkJob(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL); |
| } |
| |
| #else /* crond without sendmail */ |
| |
| static void RunJob(const char *user, CronLine *line) |
| { |
| struct passwd *pas; |
| pid_t pid; |
| |
| /* prepare things before vfork */ |
| pas = getpwnam(user); |
| if (!pas) { |
| crondlog(LVL9 "can't get uid for %s", user); |
| goto err; |
| } |
| SetEnv(pas); |
| |
| /* fork as the user in question and run program */ |
| pid = vfork(); |
| if (pid == 0) { |
| /* CHILD */ |
| /* change running state to the user in question */ |
| ChangeUser(pas); |
| if (DebugOpt) { |
| crondlog(LVL5 "child running %s", DEFAULT_SHELL); |
| } |
| execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_Shell, NULL); |
| crondlog(ERR20 "can't exec, user %s cmd %s %s %s", user, |
| DEFAULT_SHELL, "-c", line->cl_Shell); |
| _exit(0); |
| } |
| if (pid < 0) { |
| /* FORK FAILED */ |
| crondlog(ERR20 "can't vfork"); |
| err: |
| pid = 0; |
| } |
| line->cl_Pid = pid; |
| } |
| |
| #endif /* ENABLE_FEATURE_CROND_CALL_SENDMAIL */ |