diff options
Diffstat (limited to 'miscutils/crond.c')
| -rw-r--r-- | miscutils/crond.c | 935 |
1 files changed, 935 insertions, 0 deletions
diff --git a/miscutils/crond.c b/miscutils/crond.c new file mode 100644 index 0000000..732fbb1 --- /dev/null +++ b/miscutils/crond.c @@ -0,0 +1,935 @@ +/* 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 */ + char *cl_MailTo; /* whom to mail results */ +#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_FEATURE_CROND_D, +}; +#if ENABLE_FEATURE_CROND_D +#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 >= (int)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 UNUSED_PARAM, 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_FEATURE_CROND_D(":d-l") + ":l+:d+"; /* -l and -d have numeric param */ + opt = getopt32(argv, "l:L:fbSc:" USE_FEATURE_CROND_D("d:"), + &LogLevel, &LogFile, &CDir + USE_FEATURE_CROND_D(,&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... */ + xsetenv("SHELL", DEFAULT_SHELL); /* 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 + xsetenv("USER", pas->pw_name); + xsetenv("HOME", pas->pw_dir); +#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 void 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; + + // this can't happen due to config_read() + /*if (base == NULL) + return;*/ + + while (1) { + 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) { + goto err; + } + 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) { + goto err; + } + } while (n1 != n2); + + } + if (*ptr != ',') { + break; + } + ++ptr; + n1 = -1; + n2 = -1; + } + + if (*ptr) { + err: + crondlog(WARN9 "user %s: parse error at %s", user, base); + return; + } + + 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); + } +} + +static void FixDayDow(CronLine *line) +{ + unsigned 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) +{ + struct parser_t *parser; + struct stat sbuf; + int maxLines; + char *tokens[6]; +#if ENABLE_FEATURE_CROND_CALL_SENDMAIL + char *mailTo = NULL; +#endif + + if (!fileName) + return; + + DeleteFile(fileName); + parser = config_open(fileName); + if (!parser) + return; + + maxLines = (strcmp(fileName, "root") == 0) ? 65535 : MAXLINES; + + if (fstat(fileno(parser->fp), &sbuf) == 0 && sbuf.st_uid == DaemonUid) { + CronFile *file = xzalloc(sizeof(CronFile)); + CronLine **pline; + int n; + + file->cf_User = xstrdup(fileName); + pline = &file->cf_LineBase; + + while (1) { + CronLine *line; + + if (!--maxLines) + break; + n = config_read(parser, tokens, 6, 1, "# \t", PARSE_NORMAL | PARSE_KEEP_COPY); + if (!n) + break; + + if (DebugOpt) + crondlog(LVL5 "user:%s entry:%s", fileName, parser->data); + + /* check if line is setting MAILTO= */ + if (0 == strncmp(tokens[0], "MAILTO=", 7)) { +#if ENABLE_FEATURE_CROND_CALL_SENDMAIL + free(mailTo); + mailTo = (tokens[0][7]) ? xstrdup(&tokens[0][7]) : NULL; +#endif /* otherwise just ignore such lines */ + continue; + } + /* check if a minimum of tokens is specified */ + if (n < 6) + continue; + *pline = line = xzalloc(sizeof(*line)); + /* parse date ranges */ + ParseField(file->cf_User, line->cl_Mins, 60, 0, NULL, tokens[0]); + ParseField(file->cf_User, line->cl_Hrs, 24, 0, NULL, tokens[1]); + ParseField(file->cf_User, line->cl_Days, 32, 0, NULL, tokens[2]); + ParseField(file->cf_User, line->cl_Mons, 12, -1, MonAry, tokens[3]); + ParseField(file->cf_User, line->cl_Dow, 7, 0, DowAry, tokens[4]); + /* + * fix days and dow - if one is not "*" and the other + * is "*", the other is set to 0, and vise-versa + */ + FixDayDow(line); +#if ENABLE_FEATURE_CROND_CALL_SENDMAIL + /* copy mailto (can be NULL) */ + line->cl_MailTo = xstrdup(mailTo); +#endif + /* copy command */ + line->cl_Shell = xstrdup(tokens[5]); + if (DebugOpt) { + crondlog(LVL5 " command:%s", tokens[5]); + } + pline = &line->cl_Next; +//bb_error_msg("M[%s]F[%s][%s][%s][%s][%s][%s]", mailTo, tokens[0], tokens[1], tokens[2], tokens[3], tokens[4], tokens[5]); + } + *pline = NULL; + + file->cf_Next = FileBase; + FileBase = file; + + if (maxLines == 0) { + crondlog(WARN9 "user %s: too many lines", fileName); + } + } + config_close(parser); +} + +static void CheckUpdates(void) +{ + FILE *fi; + char buf[256]; + + fi = fopen_for_read(CRONUPDATE); + 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)) != NULL) { + 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); + } + /* crond 3.0pl1-100 puts tasks in separate process groups */ + bb_setpgrp(); + execlp(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(EXIT_SUCCESS); + } + + 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 = -1; + + line->cl_Pid = 0; + line->cl_MailFlag = 0; + + if (line->cl_MailTo) { + /* 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", line->cl_MailTo, + 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; + } + if (line->cl_MailTo) + 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); + } + /* crond 3.0pl1-100 puts tasks in separate process groups */ + bb_setpgrp(); + 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(EXIT_SUCCESS); + } + if (pid < 0) { + /* FORK FAILED */ + crondlog(ERR20 "can't vfork"); + err: + pid = 0; + } + line->cl_Pid = pid; +} + +#endif /* ENABLE_FEATURE_CROND_CALL_SENDMAIL */ |