[linux-2.6-block.git] / net / netfilter / xt_LED.c

/*
 * xt_LED.c - netfilter target to make LEDs blink upon packet matches
 *
 * Copyright (C) 2008 Adam Nielsen <a.nielsen@shikadi.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301 USA.
 *
 */

#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>

#include <linux/netfilter/xt_LED.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Adam Nielsen <a.nielsen@shikadi.net>");
MODULE_DESCRIPTION("Xtables: trigger LED devices on packet match");

/*
 * 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 led_trigger netfilter_led_trigger;
	struct timer_list timer;
};

static unsigned int
led_tg(struct sk_buff *skb, const struct xt_target_param *par)
{
	const struct xt_led_info *ledinfo = par->targinfo;
	struct xt_led_info_internal *ledinternal = ledinfo->internal_data;

	/*
	 * If "always blink" is enabled, and there's still some time until the
	 * LED will switch off, briefly switch it off now.
	 */
	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_FULL);

	/* If there's a positive delay, start/update the timer */
	if (ledinfo->delay > 0) {
		mod_timer(&ledinternal->timer,
			  jiffies + msecs_to_jiffies(ledinfo->delay));

	/* Otherwise if there was no delay given, blink as fast as possible */
	} else if (ledinfo->delay == 0) {
		led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF);
	}

	/* else the delay is negative, which means switch on and stay on */

	return XT_CONTINUE;
}

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;

	led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF);
}

static bool led_tg_check(const struct xt_tgchk_param *par)
{
	struct xt_led_info *ledinfo = par->targinfo;
	struct xt_led_info_internal *ledinternal;
	int err;

	if (ledinfo->id[0] == '\0') {
		printk(KERN_ERR KBUILD_MODNAME ": No 'id' parameter given.\n");
		return false;
	}

	ledinternal = kzalloc(sizeof(struct xt_led_info_internal), GFP_KERNEL);
	if (!ledinternal) {
		printk(KERN_CRIT KBUILD_MODNAME ": out of memory\n");
		return false;
	}

	ledinternal->netfilter_led_trigger.name = ledinfo->id;

	err = led_trigger_register(&ledinternal->netfilter_led_trigger);
	if (err) {
		printk(KERN_CRIT KBUILD_MODNAME
			": led_trigger_register() failed\n");
		if (err == -EEXIST)
			printk(KERN_ERR KBUILD_MODNAME
				": Trigger name is already in use.\n");
		goto exit_alloc;
	}

	/* See if we need to set up a timer */
	if (ledinfo->delay > 0)
		setup_timer(&ledinternal->timer, led_timeout_callback,
			    (unsigned long)ledinfo);

	ledinfo->internal_data = ledinternal;

	return true;

exit_alloc:
	kfree(ledinternal);

	return false;
}

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;

	if (ledinfo->delay > 0)
		del_timer_sync(&ledinternal->timer);

	led_trigger_unregister(&ledinternal->netfilter_led_trigger);
	kfree(ledinternal);
}

static struct xt_target led_tg_reg __read_mostly = {
	.name		= "LED",
	.revision	= 0,
	.family		= NFPROTO_UNSPEC,
	.target		= led_tg,
	.targetsize	= XT_ALIGN(sizeof(struct xt_led_info)),
	.checkentry	= led_tg_check,
	.destroy	= led_tg_destroy,
	.me		= THIS_MODULE,
};

static int __init led_tg_init(void)
{
	return xt_register_target(&led_tg_reg);
}

static void __exit led_tg_exit(void)
{
	xt_unregister_target(&led_tg_reg);
}

module_init(led_tg_init);
module_exit(led_tg_exit);
Commit	Line	Data
268cb38e AN	1	/*
	2	* xt_LED.c - netfilter target to make LEDs blink upon packet matches
	3	*
	4	* Copyright (C) 2008 Adam Nielsen <a.nielsen@shikadi.net>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; version 2 of the License.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	18	* 02110-1301 USA.
	19	*
	20	*/
	21
	22	#include <linux/module.h>
	23	#include <linux/skbuff.h>
	24	#include <linux/netfilter/x_tables.h>
5a0e3ad6	25	#include <linux/slab.h>
268cb38e AN	26	#include <linux/leds.h>
	27	#include <linux/mutex.h>
	28
	29	#include <linux/netfilter/xt_LED.h>
	30
	31	MODULE_LICENSE("GPL");
	32	MODULE_AUTHOR("Adam Nielsen <a.nielsen@shikadi.net>");
	33	MODULE_DESCRIPTION("Xtables: trigger LED devices on packet match");
	34
	35	/*
	36	* This is declared in here (the kernel module) only, to avoid having these
	37	* dependencies in userspace code. This is what xt_led_info.internal_data
	38	* points to.
	39	*/
	40	struct xt_led_info_internal {
	41	struct led_trigger netfilter_led_trigger;
	42	struct timer_list timer;
	43	};
	44
	45	static unsigned int
	46	led_tg(struct sk_buff skb, const struct xt_target_param par)
	47	{
	48	const struct xt_led_info *ledinfo = par->targinfo;
	49	struct xt_led_info_internal *ledinternal = ledinfo->internal_data;
	50
	51	/*
	52	* If "always blink" is enabled, and there's still some time until the
	53	* LED will switch off, briefly switch it off now.
	54	*/
	55	if ((ledinfo->delay > 0) && ledinfo->always_blink &&
	56	timer_pending(&ledinternal->timer))
	57	led_trigger_event(&ledinternal->netfilter_led_trigger,LED_OFF);
	58
	59	led_trigger_event(&ledinternal->netfilter_led_trigger, LED_FULL);
	60
	61	/* If there's a positive delay, start/update the timer */
	62	if (ledinfo->delay > 0) {
	63	mod_timer(&ledinternal->timer,
	64	jiffies + msecs_to_jiffies(ledinfo->delay));
	65
	66	/* Otherwise if there was no delay given, blink as fast as possible */
	67	} else if (ledinfo->delay == 0) {
	68	led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF);
	69	}
	70
	71	/* else the delay is negative, which means switch on and stay on */
	72
	73	return XT_CONTINUE;
	74	}
	75
	76	static void led_timeout_callback(unsigned long data)
	77	{
	78	struct xt_led_info ledinfo = (struct xt_led_info )data;
	79	struct xt_led_info_internal *ledinternal = ledinfo->internal_data;
	80
	81	led_trigger_event(&ledinternal->netfilter_led_trigger, LED_OFF);
	82	}
	83
	84	static bool led_tg_check(const struct xt_tgchk_param *par)
	85	{
	86	struct xt_led_info *ledinfo = par->targinfo;
	87	struct xt_led_info_internal *ledinternal;
	88	int err;
	89
90	if (ledinfo->id[0] == '\0') {
91	printk(KERN_ERR KBUILD_MODNAME ": No 'id' parameter given.\n");
92	return false;
93	}
94
95	ledinternal = kzalloc(sizeof(struct xt_led_info_internal), GFP_KERNEL);
96	if (!ledinternal) {
97	printk(KERN_CRIT KBUILD_MODNAME ": out of memory\n");
98	return false;
99	}
100
101	ledinternal->netfilter_led_trigger.name = ledinfo->id;
102
103	err = led_trigger_register(&ledinternal->netfilter_led_trigger);
104	if (err) {
105	printk(KERN_CRIT KBUILD_MODNAME
106	": led_trigger_register() failed\n");
107	if (err == -EEXIST)
108	printk(KERN_ERR KBUILD_MODNAME
109	": Trigger name is already in use.\n");
110	goto exit_alloc;
111	}
112
113	/* See if we need to set up a timer */
114	if (ledinfo->delay > 0)
115	setup_timer(&ledinternal->timer, led_timeout_callback,
116	(unsigned long)ledinfo);
117
118	ledinfo->internal_data = ledinternal;
119
120	return true;
121
122	exit_alloc:
123	kfree(ledinternal);
124
125	return false;
126	}
127
128	static void led_tg_destroy(const struct xt_tgdtor_param *par)
129	{
130	const struct xt_led_info *ledinfo = par->targinfo;
131	struct xt_led_info_internal *ledinternal = ledinfo->internal_data;
132
133	if (ledinfo->delay > 0)
134	del_timer_sync(&ledinternal->timer);
135
136	led_trigger_unregister(&ledinternal->netfilter_led_trigger);
137	kfree(ledinternal);
138	}
139
140	static struct xt_target led_tg_reg __read_mostly = {
141	.name = "LED",
142	.revision = 0,
143	.family = NFPROTO_UNSPEC,
144	.target = led_tg,
145	.targetsize = XT_ALIGN(sizeof(struct xt_led_info)),
146	.checkentry = led_tg_check,
147	.destroy = led_tg_destroy,
148	.me = THIS_MODULE,
149	};
150
151	static int __init led_tg_init(void)
152	{
153	return xt_register_target(&led_tg_reg);
154	}
155
156	static void __exit led_tg_exit(void)
157	{
158	xt_unregister_target(&led_tg_reg);
159	}
160
161	module_init(led_tg_init);
162	module_exit(led_tg_exit);