1 /* Kernel module to match running CPU */
2
3 /*
4 * Might be used to distribute connections on several daemons, if
5 * RPS (Remote Packet Steering) is enabled or NIC is multiqueue capable,
6 * each RX queue IRQ affined to one CPU (1:1 mapping)
7 *
8 */
9
10 /* (C) 2010 Eric Dumazet
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 */
16
17 #include <linux/module.h>
18 #include <linux/skbuff.h>
19 #include <linux/netfilter/xt_cpu.h>
20 #include <linux/netfilter/x_tables.h>
21
22 MODULE_LICENSE("GPL");
23 MODULE_AUTHOR("Eric Dumazet <eric.dumazet@gmail.com>");
24 MODULE_DESCRIPTION("Xtables: CPU match");
25 MODULE_ALIAS("ipt_cpu");
26 MODULE_ALIAS("ip6t_cpu");
27
cpu_mt_check(const struct xt_mtchk_param * par)28 static int cpu_mt_check(const struct xt_mtchk_param *par)
29 {
30 const struct xt_cpu_info *info = par->matchinfo;
31
32 if (info->invert & ~1)
33 return -EINVAL;
34 return 0;
35 }
36
cpu_mt(const struct sk_buff * skb,struct xt_action_param * par)37 static bool cpu_mt(const struct sk_buff *skb, struct xt_action_param *par)
38 {
39 const struct xt_cpu_info *info = par->matchinfo;
40
41 return (info->cpu == smp_processor_id()) ^ info->invert;
42 }
43
44 static struct xt_match cpu_mt_reg __read_mostly = {
45 .name = "cpu",
46 .revision = 0,
47 .family = NFPROTO_UNSPEC,
48 .checkentry = cpu_mt_check,
49 .match = cpu_mt,
50 .matchsize = sizeof(struct xt_cpu_info),
51 .me = THIS_MODULE,
52 };
53
cpu_mt_init(void)54 static int __init cpu_mt_init(void)
55 {
56 return xt_register_match(&cpu_mt_reg);
57 }
58
cpu_mt_exit(void)59 static void __exit cpu_mt_exit(void)
60 {
61 xt_unregister_match(&cpu_mt_reg);
62 }
63
64 module_init(cpu_mt_init);
65 module_exit(cpu_mt_exit);
66