1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
/*
* 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/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 = 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);
|
