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hush/miscutils/crond.c
Eric Andersen 080ddc1c19 mjn3 noticed that crond and crontab had #include <pwd.h> and #include <grp.h> 
but this conflicted with the internal pwd_.h and grp_.h.  Removing these
headers is correct, since the correct pwd/grp headers will be included via
busybox.h
 -Erik
2002-10-22 20:08:51 +00:00

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/*
* crond -d[#] -c <crondir> -f -b
*
* run as root, but NOT setuid root
*
* Copyright 1994 Matthew Dillon (dillon@apollo.west.oic.com)
* May be distributed under the GNU General Public License
*
* Vladimir Oleynik <dzo@simtreas.ru> (C) 2002 to be used in busybox
*/
#define VERSION "2.3.2"
#undef FEATURE_DEBUG_OPT
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <time.h>
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>
#include <syslog.h>
#include <signal.h>
#include <getopt.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/resource.h>
#include "busybox.h"
#define arysize(ary) (sizeof(ary)/sizeof((ary)[0]))
#ifndef CRONTABS
#define CRONTABS "/var/spool/cron/crontabs"
#endif
#ifndef TMPDIR
#define TMPDIR "/var/spool/cron"
#endif
#ifndef LOG_FILE
#define LOG_FILE "/var/log/cron"
#endif
#ifndef SENDMAIL
#define SENDMAIL "/usr/sbin/sendmail"
#endif
#ifndef SENDMAIL_ARGS
#define SENDMAIL_ARGS "-t", "-oem", "-i"
#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 */
int cf_Ready; /* bool: one or more jobs ready */
int cf_Running; /* bool: one or more jobs running */
int cf_Deleted; /* marked for deletion, ignore */
} CronFile;
typedef struct CronLine {
struct CronLine *cl_Next;
char *cl_Shell; /* shell command */
int cl_Pid; /* running pid, 0, or armed (-1) */
int cl_MailFlag; /* running pid is for mail */
int cl_MailPos; /* 'empty file' size */
char cl_Mins[60]; /* 0-59 */
char cl_Hrs[24]; /* 0-23 */
char cl_Days[32]; /* 1-31 */
char cl_Mons[12]; /* 0-11 */
char cl_Dow[7]; /* 0-6, beginning sunday */
} CronLine;
#define RUN_RANOUT 1
#define RUN_RUNNING 2
#define RUN_FAILED 3
#define DaemonUid 0
#ifdef FEATURE_DEBUG_OPT
static short DebugOpt;
#endif
static short LogLevel = 8;
static short ForegroundOpt;
static short LoggerOpt;
static const char *LogFile = LOG_FILE;
static const char *CDir = CRONTABS;
static void log(int level, const char *ctl, ...);
static void log9(const char *ctl, ...);
static void startlogger(void);
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(CronFile *file, CronLine *line);
static void EndJob(const CronFile *file, CronLine *line);
static void DeleteFile(const char *userName);
static CronFile *FileBase;
int
crond_main(int ac, char **av)
{
int i;
opterr = 0; /* disable getopt 'errors' message.*/
while ((i = getopt(ac,av,
#ifdef FEATURE_DEBUG_OPT
"d:"
#endif
"l:L:fbSc:")) != EOF){
switch (i){
case 'l':
LogLevel = atoi(optarg);
break;
#ifdef FEATURE_DEBUG_OPT
case 'd':
DebugOpt = atoi(optarg);
LogLevel = 0;
break;
#endif
case 'f':
ForegroundOpt = 1;
break;
case 'b':
ForegroundOpt = 0;
break;
case 'S': /* select logging to syslog */
LoggerOpt = 0;
break;
case 'L': /* select internal file logger */
LoggerOpt = 1;
if (*optarg != 0) LogFile = optarg;
break;
case 'c':
if (*optarg != 0) CDir = optarg;
break;
default: /* parse error */
show_usage();
}
}
/*
* change directory
*/
if (chdir(CDir) != 0)
perror_msg_and_die("chdir");
/*
* close stdin and stdout, stderr.
* close unused descriptors - don't need.
* optional detach from controlling terminal
*/
if (ForegroundOpt == 0) {
if(daemon(1, 0) < 0)
perror_msg_and_die("daemon");
}
(void)startlogger(); /* need if syslog mode selected */
signal(SIGHUP,SIG_IGN); /* hmm.. but, if kill -HUP original
* version - his died. ;(
*/
/*
* main loop - synchronize to 1 second after the minute, minimum sleep
* of 1 second.
*/
log(9,"%s " VERSION " dillon, started, log level %d\n", av[0], LogLevel);
SynchronizeDir();
{
time_t t1 = time(NULL);
time_t t2;
long dt;
short rescan = 60;
short sleep_time = 60;
for (;;) {
sleep((sleep_time + 1) - (short)(time(NULL) % sleep_time));
t2 = time(NULL);
dt = t2 - 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();
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt)
log(5, "Wakeup dt=%d\n", dt);
#endif
if (dt < -60*60 || dt > 60*60) {
t1 = t2;
log9("time disparity of %d minutes detected\n", dt / 60);
} else if (dt > 0) {
TestJobs(t1, t2);
RunJobs();
sleep(5);
if (CheckJobs() > 0)
sleep_time = 10;
else
sleep_time = 60;
t1 = t2;
}
}
}
/* not reached */
}
static void
vlog(int level, int MLOG_LEVEL, const char *ctl, va_list va)
{
char buf[1024];
int logfd;
if (level >= LogLevel) {
vsnprintf(buf,sizeof(buf), ctl, va);
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt) fprintf(stderr,"%s",buf);
else
#endif
if (LoggerOpt == 0) syslog(MLOG_LEVEL, "%s", buf);
else {
if ((logfd = open(LogFile,O_WRONLY|O_CREAT|O_APPEND,600)) >= 0){
write(logfd, buf, strlen(buf));
close(logfd);
} else
#ifdef FEATURE_DEBUG_OPT
perror_msg("Can't open log file")
#endif
;
}
}
}
/*
set log_level=9 and log messages
*/
static void
log9(const char *ctl, ...)
{
va_list va;
va_start(va, ctl);
vlog(9, LOG_WARNING, ctl, va);
va_end(va);
}
/*
normal logger call point.
*/
static void
log(int level, const char *ctl, ...)
{
va_list va;
va_start(va, ctl);
vlog(level, LOG_NOTICE, ctl, va);
va_end(va);
}
/*
Original: void
logfd(int fd, const char *ctl, ...)
Updated to: log_error (used by jobs.c)
*/
static void
log_err(const char *ctl, ...)
{
va_list va;
va_start(va, ctl);
vlog(20, LOG_ERR, ctl, va);
va_end(va);
}
/*
used by jobs.c (write to temp file..)
*/
static void
fdprintf(int fd, const char *ctl, ...)
{
va_list va;
va_start(va, ctl);
vdprintf(fd, ctl, va);
va_end(va);
}
static int
ChangeUser(const char *user, short dochdir)
{
struct passwd *pas;
/*
* Obtain password entry and change privilages
*/
if ((pas = getpwnam(user)) == 0) {
log(9, "failed to get uid for %s", user);
return(-1);
}
setenv("USER", pas->pw_name, 1);
setenv("HOME", pas->pw_dir, 1);
setenv("SHELL", "/bin/sh", 1);
/*
* Change running state to the user in question
*/
if (initgroups(user, pas->pw_gid) < 0) {
log(9, "initgroups failed: %s %m", user);
return(-1);
}
if (setregid(pas->pw_gid, pas->pw_gid) < 0) {
log(9, "setregid failed: %s %d", user, pas->pw_gid);
return(-1);
}
if (setreuid(pas->pw_uid, pas->pw_uid) < 0) {
log(9, "setreuid failed: %s %d", user, pas->pw_uid);
return(-1);
}
if (dochdir) {
if (chdir(pas->pw_dir) < 0) {
log(8, "chdir failed: %s %s", user, pas->pw_dir);
if (chdir(TMPDIR) < 0) {
log(9, "chdir failed: %s %s", TMPDIR, user);
return(-1);
}
}
}
return(pas->pw_uid);
}
static void
startlogger(void)
{
int logfd;
if (LoggerOpt == 0)
openlog(applet_name, LOG_CONS|LOG_PID,LOG_CRON);
else { /* test logfile */
if ((logfd = open(LogFile,O_WRONLY|O_CREAT|O_APPEND,600)) >= 0)
close(logfd);
else
#ifdef FEATURE_DEBUG_OPT
printf("Failed to open log file '%s' reason: %m", LogFile)
#endif
;
}
}
static const char * const DowAry[] = {
"sun",
"mon",
"tue",
"wed",
"thu",
"fri",
"sat",
"Sun",
"Mon",
"Tue",
"Wed",
"Thu",
"Fri",
"Sat",
NULL
};
static const char * const MonAry[] = {
"jan",
"feb",
"mar",
"apr",
"may",
"jun",
"jul",
"aug",
"sep",
"oct",
"nov",
"dec",
"Jan",
"Feb",
"Mar",
"Apr",
"May",
"Jun",
"Jul",
"Aug",
"Sep",
"Oct",
"Nov",
"Dec",
NULL
};
static char *
ParseField(char *user, char *ary, int modvalue, int off,
const char * const *names, char *ptr)
{
char *base = ptr;
int n1 = -1;
int n2 = -1;
if (base == NULL)
return(NULL);
while (*ptr != ' ' && *ptr != '\t' && *ptr != '\n') {
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 (*ptr >= '0' && *ptr <= '9') {
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) {
if (strncmp(ptr, names[i], strlen(names[i])) == 0) {
break;
}
}
if (names[i]) {
ptr += strlen(names[i]);
if (n1 < 0)
n1 = i;
else
n2 = i;
skip = 1;
}
}
/*
* handle optional range '-'
*/
if (skip == 0) {
log9("failed user %s parsing %s\n", 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;
}
} while (n1 != n2 && --failsafe);
if (failsafe == 0) {
log9("failed user %s parsing %s\n", user, base);
return(NULL);
}
}
if (*ptr != ',')
break;
++ptr;
n1 = -1;
n2 = -1;
}
if (*ptr != ' ' && *ptr != '\t' && *ptr != '\n') {
log9("failed user %s parsing %s\n", user, base);
return(NULL);
}
while (*ptr == ' ' || *ptr == '\t' || *ptr == '\n')
++ptr;
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt) {
int i;
for (i = 0; i < modvalue; ++i)
log(5, "%d", ary[i]);
log(5, "\n");
}
#endif
return(ptr);
}
static void
FixDayDow(CronLine *line)
{
short i;
short weekUsed = 0;
short daysUsed = 0;
for (i = 0; i < arysize(line->cl_Dow); ++i) {
if (line->cl_Dow[i] == 0) {
weekUsed = 1;
break;
}
}
for (i = 0; i < arysize(line->cl_Days); ++i) {
if (line->cl_Days[i] == 0) {
daysUsed = 1;
break;
}
}
if (weekUsed && !daysUsed) {
memset(line->cl_Days, 0, sizeof(line->cl_Days));
}
if (daysUsed && !weekUsed) {
memset(line->cl_Dow, 0, sizeof(line->cl_Dow));
}
}
static void
SynchronizeFile(const char *fileName)
{
int maxEntries = MAXLINES;
int maxLines;
char buf[1024];
if (strcmp(fileName, "root") == 0)
maxEntries = 65535;
maxLines = maxEntries * 10;
if (fileName) {
FILE *fi;
DeleteFile(fileName);
if ((fi = fopen(fileName, "r")) != NULL) {
struct stat sbuf;
if (fstat(fileno(fi), &sbuf) == 0 && sbuf.st_uid == DaemonUid) {
CronFile *file = calloc(1, sizeof(CronFile));
CronLine **pline;
file->cf_User = strdup(fileName);
pline = &file->cf_LineBase;
while (fgets(buf, sizeof(buf), fi) != NULL && --maxLines) {
CronLine line;
char *ptr;
if (buf[0])
buf[strlen(buf)-1] = 0;
if (buf[0] == 0 || buf[0] == '#' || buf[0] == ' ' || buf[0] == '\t')
continue;
if (--maxEntries == 0)
break;
memset(&line, 0, sizeof(line));
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt)
log9("User %s Entry %s\n", fileName, buf);
#endif
/*
* 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)
continue;
/*
* fix days and dow - if one is not * and the other
* is *, the other is set to 0, and vise-versa
*/
FixDayDow(&line);
*pline = calloc(1, sizeof(CronLine));
**pline = line;
/*
* copy command
*/
(*pline)->cl_Shell = strdup(ptr);
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt) {
log9(" Command %s\n", ptr);
}
#endif
pline = &((*pline)->cl_Next);
}
*pline = NULL;
file->cf_Next = FileBase;
FileBase = file;
if (maxLines == 0 || maxEntries == 0)
log9("Maximum number of lines reached for user %s\n", fileName);
}
fclose(fi);
}
}
}
static void
CheckUpdates(void)
{
FILE *fi;
char buf[256];
if ((fi = fopen(CRONUPDATE, "r")) != NULL) {
remove(CRONUPDATE);
while (fgets(buf, sizeof(buf), fi) != NULL) {
SynchronizeFile(strtok(buf, " \t\r\n"));
}
fclose(fi);
}
}
static void
SynchronizeDir(void)
{
/*
* Attempt to delete the database. Note that we have to make a copy
* of the string
*/
for (;;) {
CronFile *file;
char *user;
for (file = FileBase; file && file->cf_Deleted; file = file->cf_Next)
;
if (file == NULL)
break;
user = strdup(file->cf_User);
DeleteFile(user);
free(user);
}
/*
* Remove cron update file
*
* Re-chdir, in case directory was renamed & deleted, or otherwise
* screwed up.
*
* scan directory and add associated users
*/
remove(CRONUPDATE);
if (chdir(CDir) < 0) {
log9("unable to find %s\n", CDir);
exit(20);
}
{
DIR *dir;
struct dirent *den;
if ((dir = opendir("."))) {
while ((den = readdir(dir))) {
if (strchr(den->d_name, '.') != NULL)
continue;
if (getpwnam(den->d_name))
SynchronizeFile(den->d_name);
else
log(7, "ignoring %s\n", den->d_name);
}
closedir(dir);
} else {
log9("Unable to open current dir!\n");
exit(20);
}
}
}
/*
* 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)
{
short nJobs = 0;
time_t t;
/*
* Find jobs > t1 and <= t2
*/
for (t = t1 - t1 % 60; t <= t2; t += 60) {
if (t > t1) {
struct tm *tp = localtime(&t);
CronFile *file;
CronLine *line;
for (file = FileBase; file; file = file->cf_Next) {
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt)
log(5, "FILE %s:\n", file->cf_User);
#endif
if (file->cf_Deleted)
continue;
for (line = file->cf_LineBase; line; line = line->cl_Next) {
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt)
log(5, " LINE %s\n", line->cl_Shell);
#endif
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]
) {
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt)
log(5, " JobToDo: %d %s\n", line->cl_Pid, line->cl_Shell);
#endif
if (line->cl_Pid > 0) {
log(8, " process already running: %s %s\n",
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) {
file->cf_Ready = 0;
for (line = file->cf_LineBase; line; line = line->cl_Next) {
if (line->cl_Pid < 0) {
RunJob(file, line);
log(8, "USER %s pid %3d cmd %s\n",
file->cf_User,
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) {
if (line->cl_Pid > 0) {
int status;
int r = wait4(line->cl_Pid, &status, WNOHANG, NULL);
if (r < 0 || r == line->cl_Pid) {
EndJob(file, line);
if (line->cl_Pid)
file->cf_Running = 1;
} else if (r == 0) {
file->cf_Running = 1;
}
}
}
}
nStillRunning += file->cf_Running;
}
return(nStillRunning);
}
static void
RunJob(CronFile *file, 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), TMPDIR "/cron.%s.%d",
file->cf_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",
file->cf_User,
line->cl_Shell
);
line->cl_MailPos = lseek(mailFd, 0, 1);
}
/*
* Fork as the user in question and run program
*/
if ((line->cl_Pid = fork()) == 0) {
/*
* CHILD, FORK OK
*/
/*
* Change running state to the user in question
*/
if (ChangeUser(file->cf_User, 1) < 0)
return;
#ifdef FEATURE_DEBUG_OPT
if (DebugOpt)
log(5, "Child Running %s\n", line->cl_Shell);
#endif
/*
* stdin is already /dev/null, setup stdout and stderr
*/
if (mailFd >= 0) {
dup2(mailFd, 1);
dup2(mailFd, 2);
close(mailFd);
} else {
log_err("unable to create mail file user %s file %s, output to /dev/null\n",
file->cf_User,
mailFile
);
}
execl("/bin/sh", "/bin/sh", "-c", line->cl_Shell, NULL, NULL);
log_err("unable to exec, user %s cmd /bin/sh -c %s\n",
file->cf_User,
line->cl_Shell
);
fdprintf(1, "Exec failed: /bin/sh -c %s\n", line->cl_Shell);
exit(0);
} else if (line->cl_Pid < 0) {
/*
* PARENT, FORK FAILED
*/
log_err("couldn't fork, user %s\n", file->cf_User);
line->cl_Pid = 0;
remove(mailFile);
} else {
/*
* PARENT, FORK SUCCESS
*
* rename mail-file based on pid of process
*/
char mailFile2[128];
snprintf(mailFile2, sizeof(mailFile2), TMPDIR "/cron.%s.%d",
file->cf_User, line->cl_Pid);
rename(mailFile, mailFile2);
}
/*
* 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);
}
/*
* EndJob - called when job terminates and when mail terminates
*/
static void
EndJob(const CronFile *file, 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), TMPDIR "/cron.%s.%d",
file->cf_User, line->cl_Pid);
line->cl_Pid = 0;
if (line->cl_MailFlag != 1)
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);
remove(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_Pid = fork()) == 0) {
/*
* CHILD, FORK OK
*/
/*
* change user id - no way in hell security can be compromised
* by the mailing and we already verified the mail file.
*/
if (ChangeUser(file->cf_User, 1) < 0)
exit(0);
/*
* run sendmail with mail file as standard input, only if
* mail file exists!
*/
dup2(mailFd, 0);
dup2(1, 2);
close(mailFd);
execl(SENDMAIL, SENDMAIL, SENDMAIL_ARGS, NULL, NULL);
log_err("unable to exec %s %s, user %s, output to sink null",
SENDMAIL,
SENDMAIL_ARGS,
file->cf_User
);
exit(0);
} else if (line->cl_Pid < 0) {
/*
* PARENT, FORK FAILED
*/
log_err("unable to fork, user %s", file->cf_User);
line->cl_Pid = 0;
} else {
/*
* PARENT, FORK OK
*/
}
close(mailFd);
}
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