net: Remove unnecessary returns from void function()s
[safe/jmp/linux-2.6] / net / netfilter / xt_LED.c
index 22b5b70..a414050 100644 (file)
@@ -22,6 +22,7 @@
 #include <linux/module.h>
 #include <linux/skbuff.h>
 #include <linux/netfilter/x_tables.h>
+#include <linux/slab.h>
 #include <linux/leds.h>
 #include <linux/mutex.h>
 
@@ -31,18 +32,24 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Adam Nielsen <a.nielsen@shikadi.net>");
 MODULE_DESCRIPTION("Xtables: trigger LED devices on packet match");
 
+static LIST_HEAD(xt_led_triggers);
+static DEFINE_MUTEX(xt_led_mutex);
+
 /*
  * This is declared in here (the kernel module) only, to avoid having these
  * dependencies in userspace code.  This is what xt_led_info.internal_data
  * points to.
  */
 struct xt_led_info_internal {
+       struct list_head list;
+       int refcnt;
+       char *trigger_id;
        struct led_trigger netfilter_led_trigger;
        struct timer_list timer;
 };
 
 static unsigned int
-led_tg(struct sk_buff *skb, const struct xt_target_param *par)
+led_tg(struct sk_buff *skb, const struct xt_action_param *par)
 {
        const struct xt_led_info *ledinfo = par->targinfo;
        struct xt_led_info_internal *ledinternal = ledinfo->internal_data;
@@ -53,7 +60,7 @@ led_tg(struct sk_buff *skb, const struct xt_target_param *par)
         */
        if ((ledinfo->delay > 0) && ledinfo->always_blink &&
            timer_pending(&ledinternal->timer))
-               led_trigger_event(&ledinternal->netfilter_led_trigger,LED_OFF);
+               led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF);
 
        led_trigger_event(&ledinternal->netfilter_led_trigger, LED_FULL);
 
@@ -74,12 +81,23 @@ led_tg(struct sk_buff *skb, const struct xt_target_param *par)
 
 static void led_timeout_callback(unsigned long data)
 {
-       struct xt_led_info *ledinfo = (struct xt_led_info *)data;
-       struct xt_led_info_internal *ledinternal = ledinfo->internal_data;
+       struct xt_led_info_internal *ledinternal = (struct xt_led_info_internal *)data;
 
        led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF);
 }
 
+static struct xt_led_info_internal *led_trigger_lookup(const char *name)
+{
+       struct xt_led_info_internal *ledinternal;
+
+       list_for_each_entry(ledinternal, &xt_led_triggers, list) {
+               if (!strcmp(name, ledinternal->netfilter_led_trigger.name)) {
+                       return ledinternal;
+               }
+       }
+       return NULL;
+}
+
 static int led_tg_check(const struct xt_tgchk_param *par)
 {
        struct xt_led_info *ledinfo = par->targinfo;
@@ -91,11 +109,25 @@ static int led_tg_check(const struct xt_tgchk_param *par)
                return -EINVAL;
        }
 
+       mutex_lock(&xt_led_mutex);
+
+       ledinternal = led_trigger_lookup(ledinfo->id);
+       if (ledinternal) {
+               ledinternal->refcnt++;
+               goto out;
+       }
+
+       err = -ENOMEM;
        ledinternal = kzalloc(sizeof(struct xt_led_info_internal), GFP_KERNEL);
        if (!ledinternal)
-               return -EINVAL;
+               goto exit_mutex_only;
 
-       ledinternal->netfilter_led_trigger.name = ledinfo->id;
+       ledinternal->trigger_id = kstrdup(ledinfo->id, GFP_KERNEL);
+       if (!ledinternal->trigger_id)
+               goto exit_internal_alloc;
+
+       ledinternal->refcnt = 1;
+       ledinternal->netfilter_led_trigger.name = ledinternal->trigger_id;
 
        err = led_trigger_register(&ledinternal->netfilter_led_trigger);
        if (err) {
@@ -108,14 +140,27 @@ static int led_tg_check(const struct xt_tgchk_param *par)
        /* See if we need to set up a timer */
        if (ledinfo->delay > 0)
                setup_timer(&ledinternal->timer, led_timeout_callback,
-                           (unsigned long)ledinfo);
+                           (unsigned long)ledinternal);
+
+       list_add_tail(&ledinternal->list, &xt_led_triggers);
+
+out:
+       mutex_unlock(&xt_led_mutex);
 
        ledinfo->internal_data = ledinternal;
+
        return 0;
 
 exit_alloc:
+       kfree(ledinternal->trigger_id);
+
+exit_internal_alloc:
        kfree(ledinternal);
-       return -EINVAL;
+
+exit_mutex_only:
+       mutex_unlock(&xt_led_mutex);
+
+       return err;
 }
 
 static void led_tg_destroy(const struct xt_tgdtor_param *par)
@@ -123,10 +168,23 @@ static void led_tg_destroy(const struct xt_tgdtor_param *par)
        const struct xt_led_info *ledinfo = par->targinfo;
        struct xt_led_info_internal *ledinternal = ledinfo->internal_data;
 
+       mutex_lock(&xt_led_mutex);
+
+       if (--ledinternal->refcnt) {
+               mutex_unlock(&xt_led_mutex);
+               return;
+       }
+
+       list_del(&ledinternal->list);
+
        if (ledinfo->delay > 0)
                del_timer_sync(&ledinternal->timer);
 
        led_trigger_unregister(&ledinternal->netfilter_led_trigger);
+
+       mutex_unlock(&xt_led_mutex);
+
+       kfree(ledinternal->trigger_id);
        kfree(ledinternal);
 }