int main (int argc, char **argv, char **envp)
{
struct rusage usage;
char **p;
int status, mem, skipped, memused;
int tsource, ttarget;
int v;
redirect = stderr;
safe_signal (SIGPIPE, SIG_DFL);
tsource = time (NULL);
p = parse (argv);
if (p == NULL)
{
printusage (argv);
return (EXIT_FAILURE);
}
else
{
/* Get an unused uid */
if (profile.minuid != profile.maxuid)
{
srand (time (NULL) ^ getpid ());
profile.minuid += rand () % (profile.maxuid - profile.minuid);
}
if (strcmp (usage_file, "/dev/null") != 0)
{
redirect = fopen (usage_file, "w");
chown (usage_file, profile.minuid, getgid());
chmod (usage_file, 0640);
if (redirect == NULL)
error ("Couldn't open usage file\n");
}
/* stderr from user program is junk */
junk = fopen (error_file, "w");
if (junk == NULL)
error ("Couldn't open junk file %s\n", error_file);
if (strcmp (error_file, "/dev/null") != 0)
{
chown (error_file, profile.minuid, getgid());
chmod (error_file, 0640);
}
if (setgid (profile.minuid) < 0)
{
if (errno == EPERM)
{
error ("Couldn't setgid due to permission");
}
else
{
error (NULL);
}
}
if (setuid (profile.minuid) < 0)
{
if (errno == EPERM)
{
error ("Couldn't setuid due to permission");
}
else
{
error (NULL);
}
}
if (getuid () == 0)
error ("Not changing the uid to an unpriviledged one is a BAD ideia");
if (signal (SIGALRM, wallclock) == SIG_ERR)
error ("Couldn't install signal handler");
if (alarm (profile.clock) != 0)
error ("Couldn't set alarm");
/* Fork new process */
pid = fork ();
if (pid < 0)
error (NULL);
if (pid == 0)
/* Forked/child process */
{
/* Chrooting */
if (chroot_dir != NULL)
{
if (0 != chdir(chroot_dir))
{
kill (getpid (), SIGPIPE);
error ("Can not change to chroot dir");
}
if (0 != chroot(chroot_dir))
{
kill (getpid (), SIGPIPE);
error ("Can not chroot");
}
}
/* Change dir */
if (run_dir != NULL)
{
if (0 != chdir(run_dir))
{
kill (getpid (), SIGPIPE);
error ("Cannot change to rundir");
}
}
dup2(fileno(junk), fileno(stderr));
if (setuid (profile.minuid) < 0)
error (NULL);
/* Don't run as root */
if (getuid () == 0)
error ("Running as a root is not secure!");
/* Set priority */
if (0 != setpriority(PRIO_USER,profile.minuid,NICE_LEVEL))
{
kill (getpid (), SIGPIPE);
error (NULL);
}
/* Set resource limits - memory, time etc */
setlimits(profile);
/* Execute the program */
if (execve (*p, p, envp) < 0)
{
kill (getpid (), SIGPIPE);
error (NULL);
}
}
else
/* Parent process */
{
if (setuid (profile.minuid) < 0)
error (NULL);
if (getuid () == 0)
error ("Running as a root is not secure!");
memusage_init ();
mark = OK;
/* Poll every INTERVAL ms and get the maximum *
* memory usage, exit when the child terminates */
mem = 64;
skipped = 0;
memused = 0;
do
{
msleep (INTERVAL);
memused = memusage (pid);
if (memused > -1)
{
mem = max (mem, memused);
}
else
{ /* Can not read memory usage! */
skipped++;
}
if (skipped > 10)
{ /* process is already finished or something wrong happened */
terminate (pid);
mark = MLE;
}
if (mem > profile.memory)
{
terminate (pid);
mark = MLE;
}
do
v = wait4 (pid, &status, WNOHANG | WUNTRACED, &usage);
//v = wait4 (pid, &status, WNOHANG | WUNTRACED | WCONTINUED | WEXITED, &usage);
while ((v < 0) && (errno != EINTR));
if (v < 0)
error (NULL);
}
while (v == 0);
memusage_close ();
ttarget = time (NULL);
if (mark == MLE)
printstats ("Memory Limit Exceeded\n");
else if (mark == RTLE)
printstats ("Time Limit Exceeded\n");
else
{
if (WIFEXITED (status) != 0)
{
if (WEXITSTATUS (status) != 0)
printstats ("Command exited with non-zero status (%d)\n",
WEXITSTATUS (status));
else
printstats ("OK\n");
}
else
{
if (WIFSIGNALED (status) != 0)
{
/* Was killed for a TLE (or was it an OLE) */
if (WTERMSIG (status) == SIGKILL)
mark = TLE;
else if (WTERMSIG (status) == SIGXFSZ)
mark = OLE;
else if (WTERMSIG (status) == SIGHUP)
mark = RF;
else if (WTERMSIG (status) == SIGPIPE)
mark = IE;
else
printstats ("Command terminated by signal (%d: %s)\n",
WTERMSIG (status),
name (WTERMSIG (status)));
}
else if (WIFSTOPPED (status) != 0)
printstats ("Command terminated by signal (%d: %s)\n",
WSTOPSIG (status), name (WSTOPSIG (status)));
else
printstats ("OK\n");
if (mark == TLE)
{
/* We know the child has terminated at right time(OS did). *
* But seing 1.990 as TLE while limit 2.0 is confusing. *
* So here is small adjustment for presentation. */
usage.ru_utime.tv_sec = profile.cpu;
usage.ru_utime.tv_usec = 0;
printstats ("Time Limit Exceeded\n");
}
else if (mark == OLE)
printstats ("Output Limit Exceeded\n");
else if (mark == RTLE)
printstats ("Time Limit Exceeded\n");
else if (mark == RF)
printstats ("Invalid Function\n");
else if (mark == IE)
printstats ("Internal Error\n");
}
}
printstats ("elapsed time: %d seconds\n", ttarget - tsource);
printstats ("memory usage: %d kbytes\n", mem);
printstats ("cpu usage: %0.3f seconds\n",
(float) miliseconds (&usage.ru_utime) / 1000.0);
}
}
fclose (redirect);
return (EXIT_SUCCESS);
}
int main (int argc, char **argv, char **envp)
{
struct rusage usage;
char **p;
int status, mem;
int tsource, ttarget;
int v;
redirect = stderr;
safe_signal (SIGPIPE, SIG_DFL);
tsource = time (NULL);
p = parse (argv);
if (p == NULL)
{
printusage (argv);
return (EXIT_FAILURE);
}
else
{
/*
fprintf (stderr, "profile: \"%s\"\n", limit->name);
fprintf (stderr, " cpu=%u\n mem=%u\n", (unsigned int) limit->cpu,
(unsigned int) limit->memory);
fprintf (stderr, " core=%u\n stack=%u\n", (unsigned int) limit->core,
(unsigned int) limit->stack);
fprintf (stderr, " fsize=%u\n nproc=%u\n", (unsigned int) limit->fsize,
(unsigned int) limit->nproc);
fprintf (stderr, " minuid=%u\n maxuid=%u\n", (unsigned int) limit->minuid,
(unsigned int) limit->maxuid);
fprintf (stderr, " clock=%u\n",
(unsigned int) limit->clock);
*/
/* Still missing: get an unused uid from interval */
if (profile.minuid != profile.maxuid)
{
srand (time (NULL) ^ getpid ());
profile.minuid += rand () % (profile.maxuid - profile.minuid);
}
if (setuid (profile.minuid) < 0)
error (NULL);
if (strcmp (usage_file, "/dev/null") != 0)
{
redirect = fopen (usage_file, "w");
chmod (usage_file, 0644);
if (redirect == NULL)
error ("Couldn't open redirection file\n");
}
if (getuid () == 0)
error ("Not changing the uid to an unpriviledged one is a BAD ideia");
if (signal (SIGALRM, wallclock) == SIG_ERR)
error ("Couldn't install signal handler");
if (alarm (profile.clock) != 0)
error ("Couldn't set alarm");
pid = fork ();
if (pid < 0)
error (NULL);
if (pid == 0)
{
/* change to chroot dir */
if (0 != chdir(chroot_dir))
{
kill (getpid (), SIGPIPE);
error ("Cannot change to chroot dir");
}
/* chroot to judge dir */
if (0 != chroot(chroot_dir))
{
kill (getpid (), SIGPIPE);
error ("Cannot chroot");
}
/* change to run dir */
if (0 != chdir(run_dir))
{
kill (getpid (), SIGPIPE);
error ("Cannot change to rundir");
}
if (setuid (profile.minuid) < 0)
error (NULL);
if (getuid () == 0)
error ("Not changing the uid to an unpriviledged one is a BAD ideia");
/* set priority */
if (0 != setpriority(PRIO_USER,profile.minuid,NICE_LEVEL))
{
kill (getpid (), SIGPIPE);
error (NULL);
}
/* Set Address space limit, 1 mbyte tolerancy (librarys also count!) */
/*setlimit (RLIMIT_AS, (1024 + limit->memory) * 1024); */
setlimit (RLIMIT_CORE, profile.core * 1024);
setlimit (RLIMIT_STACK, profile.stack * 1024);
setlimit (RLIMIT_FSIZE, profile.fsize * 1024);
setlimit (RLIMIT_NPROC, profile.nproc);
setlimit (RLIMIT_CPU, profile.cpu);
/* Execute the program */
if (execve (*p, p, envp) < 0)
{
kill (getpid (), SIGPIPE);
error (NULL);
}
}
else
{
if (setuid (profile.minuid) < 0)
error (NULL);
if (getuid () == 0)
error ("Not changing the uid to an unpriviledged one is a BAD ideia");
mark = OK;
/* Poll at INTERVAL ms and determine the maximum *
* memory usage, exit when the child terminates */
mem = 64;
do
{
msleep (INTERVAL);
mem = max (mem, memusage (pid));
if (mem > profile.memory)
{
terminate (pid);
mark = MLE;
}
do
v = wait4 (pid, &status, WNOHANG | WUNTRACED, &usage);
while ((v < 0) && (errno != EINTR));
if (v < 0)
error (NULL);
}
while (v == 0);
ttarget = time (NULL);
if (mark == MLE)
printstats ("Memory Limit Exceeded\n");
else if (mark == RTLE)
printstats ("Time Limit Exceeded\n");
else
{
if (WIFEXITED (status) != 0)
{
if (WEXITSTATUS (status) != 0)
printstats ("Command exited with non-zero status (%d)\n",
WEXITSTATUS (status));
else
printstats ("OK\n");
}
else
{
if (WIFSIGNALED (status) != 0)
{
/* Was killed for a TLE (or was it an OLE) */
if (WTERMSIG (status) == SIGKILL)
mark = TLE;
else if (WTERMSIG (status) == SIGXFSZ)
mark = OLE;
else if (WTERMSIG (status) == SIGHUP)
mark = RF;
else if (WTERMSIG (status) == SIGPIPE)
mark = IE;
else
printstats ("Command terminated by signal (%d: %s)\n",
WTERMSIG (status),
name (WTERMSIG (status)));
}
else if (WIFSTOPPED (status) != 0)
printstats ("Command terminated by signal (%d: %s)\n",
WSTOPSIG (status), name (WSTOPSIG (status)));
else
printstats ("OK\n");
if (mark == TLE)
{
/* Adjust the timings... although we know the child *
* was been killed just in the right time seing 1.990 *
* as TLE when the limit is 2 seconds is anoying */
usage.ru_utime.tv_sec = profile.cpu;
usage.ru_utime.tv_usec = 0;
printstats ("Time Limit Exceeded\n");
}
else if (mark == OLE)
printstats ("Output Limit Exceeded\n");
else if (mark == RTLE)
printstats ("Time Limit Exceeded\n");
else if (mark == RF)
printstats ("Invalid Function\n");
else if (mark == IE)
printstats ("Internal Error\n");
}
}
printstats ("elapsed time: %d seconds\n", ttarget - tsource);
printstats ("memory usage: %d kbytes\n", mem);
printstats ("cpu usage: %0.3f seconds\n",
(float) miliseconds (&usage.ru_utime) / 1000.0);
}
}
fclose (redirect);
return (EXIT_SUCCESS);
}
