void luasandbox_timer_start(luasandbox_timer_set * lts)
{
if (lts->is_running) {
// Already running
return;
}
lts->is_running = 1;
// Initialise usage timer
clock_gettime(LUASANDBOX_CLOCK_ID, <s->usage_start);
// Create normal timer if requested
if (!luasandbox_timer_is_zero(<s->normal_remaining)) {
lts->normal_running = 1;
luasandbox_timer_create_one(<s->normal_timer, lts->sandbox, LUASANDBOX_TIMER_NORMAL);
luasandbox_timer_set_one_time(<s->normal_timer, <s->normal_remaining);
} else {
lts->normal_running = 0;
}
// Create emergency timer if requested
if (!luasandbox_timer_is_zero(<s->emergency_remaining)) {
lts->emergency_running = 1;
luasandbox_timer_create_one(<s->emergency_timer, lts->sandbox, LUASANDBOX_TIMER_EMERGENCY);
luasandbox_timer_set_one_time(<s->emergency_timer, <s->emergency_remaining);
} else {
lts->emergency_running = 0;
}
}
int luasandbox_timer_is_expired(luasandbox_timer_set * lts)
{
if (!luasandbox_timer_is_zero(<s->limiter_limit)) {
if (luasandbox_timer_is_zero(<s->limiter_remaining)) {
return 1;
}
}
return 0;
}
int luasandbox_timer_is_expired(luasandbox_timer_set * lts)
{
if (!luasandbox_timer_is_zero(<s->normal_limit)) {
if (luasandbox_timer_is_zero(<s->normal_remaining)) {
return 1;
}
}
if (!luasandbox_timer_is_zero(<s->emergency_limit)) {
if (luasandbox_timer_is_zero(<s->emergency_remaining)) {
return 1;
}
}
return 0;
}
int luasandbox_timer_start(luasandbox_timer_set * lts)
{
if (lts->is_running) {
// Already running
return 1;
}
lts->is_running = 1;
// Initialise usage timer
clock_gettime(LUASANDBOX_CLOCK_ID, <s->usage_start);
// Create limiter timer if requested
if (!luasandbox_timer_is_zero(<s->limiter_remaining)) {
luasandbox_timer * timer = luasandbox_timer_create_one(
lts->sandbox, LUASANDBOX_TIMER_LIMITER);
if (!timer) {
lts->limiter_running = 0;
return 0;
}
lts->limiter_timer = timer;
lts->limiter_running = 1;
luasandbox_timer_set_one_time(timer, <s->limiter_remaining);
} else {
lts->limiter_running = 0;
}
return 1;
}
static void luasandbox_timer_set_one_time(luasandbox_timer * lt, struct timespec * ts)
{
struct itimerspec its;
luasandbox_timer_zero(&its.it_interval);
its.it_value = *ts;
if (luasandbox_timer_is_zero(&its.it_value)) {
// Sanity check: make sure there is at least 1 nanosecond on the timer.
its.it_value.tv_nsec = 1;
}
timer_settime(lt->timer, 0, &its, NULL);
}
static void luasandbox_timer_handle_signal(int signo, siginfo_t * info, void * context)
{
luasandbox_timer_callback_data * data;
if (signo != LUASANDBOX_SIGNAL
|| info->si_code != SI_TIMER
|| !info->si_value.sival_ptr)
{
return;
}
data = (luasandbox_timer_callback_data*)info->si_value.sival_ptr;
lua_State * L = data->sandbox->state;
if (data->type == LUASANDBOX_TIMER_EMERGENCY) {
sigset_t set;
sigemptyset(&set);
sigprocmask(SIG_SETMASK, &set, NULL);
data->sandbox->timed_out = 1;
data->sandbox->emergency_timed_out = 1;
if (data->sandbox->in_php) {
// The whole PHP request context is dirty now. We need to kill it,
// like what happens if there is a max_execution_time timeout.
zend_error(E_ERROR, "The maximum execution time for a Lua sandbox script "
"was exceeded and a PHP callback failed to return");
} else {
// The Lua state is dirty now and can't be used again.
lua_pushstring(L, "emergency timeout");
luasandbox_wrap_fatal(L);
lua_error(L);
}
} else {
luasandbox_timer_set * lts = &data->sandbox->timer;
if (luasandbox_timer_is_paused(lts)) {
// The timer is paused. luasandbox_timer_unpause will reschedule when unpaused.
clock_gettime(LUASANDBOX_CLOCK_ID, <s->normal_expired_at);
} else if (!luasandbox_timer_is_zero(<s->pause_delta)) {
// The timer is not paused, but we have a pause delta. Reschedule.
luasandbox_timer_subtract(<s->usage, <s->pause_delta);
lts->normal_remaining = lts->pause_delta;
luasandbox_timer_zero(<s->pause_delta);
luasandbox_timer_set_one_time(<s->normal_timer, <s->normal_remaining);
} else {
// Set a hook which will terminate the script execution in a graceful way
data->sandbox->timed_out = 1;
lua_sethook(L, luasandbox_timer_timeout_hook,
LUA_MASKCOUNT | LUA_MASKCALL | LUA_MASKRET | LUA_MASKLINE, 1);
}
}
}
void luasandbox_timer_unpause(luasandbox_timer_set * lts) {
struct timespec delta;
if (!luasandbox_timer_is_zero(<s->pause_start)) {
clock_gettime(LUASANDBOX_CLOCK_ID, &delta);
luasandbox_timer_subtract(&delta, <s->pause_start);
if (luasandbox_timer_is_zero(<s->normal_expired_at)) {
// Easy case, timer didn't expire while paused. Throw the whole delta
// into pause_delta for later timer and usage adjustment.
luasandbox_timer_add(<s->pause_delta, &delta);
luasandbox_timer_zero(<s->pause_start);
} else {
// If the normal limit expired, we need to fold the whole
// accumulated delta into usage immediately, and then restart the
// timer with the portion before the expiry.
// adjust usage
luasandbox_timer_subtract(<s->usage, &delta);
luasandbox_timer_subtract(<s->usage, <s->pause_delta);
// calculate timer delta
delta = lts->normal_expired_at;
luasandbox_timer_subtract(&delta, <s->pause_start);
luasandbox_timer_add(&delta, <s->pause_delta);
// Zero out pause vars and expired timestamp (since we handled it)
luasandbox_timer_zero(<s->pause_start);
luasandbox_timer_zero(<s->pause_delta);
luasandbox_timer_zero(<s->normal_expired_at);
// Restart timer
lts->normal_remaining = delta;
luasandbox_timer_set_one_time(<s->normal_timer, <s->normal_remaining);
}
}
}
void luasandbox_timer_get_usage(luasandbox_timer_set * lts, struct timespec * ts)
{
struct timespec delta;
if (lts->is_running) {
luasandbox_update_usage(lts);
}
*ts = lts->usage;
// Subtract the pause delta from the usage
luasandbox_timer_subtract(ts, <s->pause_delta);
// If currently paused, subtract the time-since-pause too
if (!luasandbox_timer_is_zero(<s->pause_start)) {
clock_gettime(LUASANDBOX_CLOCK_ID, &delta);
luasandbox_timer_subtract(&delta, <s->pause_start);
luasandbox_timer_subtract(ts, &delta);
}
}
static void luasandbox_timer_handle_limiter(luasandbox_timer * lt)
{
lua_State * L = lt->sandbox->state;
luasandbox_timer_set * lts = <->sandbox->timer;
if (luasandbox_timer_is_paused(lts)) {
// The timer is paused. luasandbox_timer_unpause will reschedule when unpaused.
// Note that we need to use lt->clock_id here since CLOCK_THREAD_CPUTIME_ID
// would get the time usage of the timer thread rather than the Lua thread.
clock_gettime(lt->clock_id, <s->limiter_expired_at);
} else if (!luasandbox_timer_is_zero(<s->pause_delta)) {
// The timer is not paused, but we have a pause delta. Reschedule.
luasandbox_timer_subtract(<s->usage, <s->pause_delta);
lts->limiter_remaining = lts->pause_delta;
luasandbox_timer_zero(<s->pause_delta);
luasandbox_timer_set_one_time(lts->limiter_timer, <s->limiter_remaining);
} else {
// Set a hook which will terminate the script execution in a graceful way
lt->sandbox->timed_out = 1;
lua_sethook(L, luasandbox_timer_timeout_hook,
LUA_MASKCOUNT | LUA_MASKCALL | LUA_MASKRET | LUA_MASKLINE, 1);
}
}
int luasandbox_timer_is_paused(luasandbox_timer_set * lts) {
return !luasandbox_timer_is_zero(<s->pause_start);
}
void luasandbox_timer_pause(luasandbox_timer_set * lts) {
if (luasandbox_timer_is_zero(<s->pause_start)) {
clock_gettime(LUASANDBOX_CLOCK_ID, <s->pause_start);
}
}
