summaryrefslogtreecommitdiffstats
path: root/net/netfilter/xt_NFQUEUE.c
blob: a9aca80a32aeb4c9b92757a20710960b094aa7aa (plain)
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
162
/* iptables module for using new netfilter netlink queue
 *
 * (C) 2005 by Harald Welte <laforge@netfilter.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/skbuff.h>

#include <linux/netfilter.h>
#include <linux/netfilter_arp.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_NFQUEUE.h>

#include <net/netfilter/nf_queue.h>

MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("Xtables: packet forwarding to netlink");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_NFQUEUE");
MODULE_ALIAS("ip6t_NFQUEUE");
MODULE_ALIAS("arpt_NFQUEUE");

static u32 jhash_initval __read_mostly;

static unsigned int
nfqueue_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct xt_NFQ_info *tinfo = par->targinfo;

	return NF_QUEUE_NR(tinfo->queuenum);
}

static unsigned int
nfqueue_tg_v1(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct xt_NFQ_info_v1 *info = par->targinfo;
	u32 queue = info->queuenum;

	if (info->queues_total > 1) {
		queue = nfqueue_hash(skb, queue, info->queues_total,
				     xt_family(par), jhash_initval);
	}
	return NF_QUEUE_NR(queue);
}

static unsigned int
nfqueue_tg_v2(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct xt_NFQ_info_v2 *info = par->targinfo;
	unsigned int ret = nfqueue_tg_v1(skb, par);

	if (info->bypass)
		ret |= NF_VERDICT_FLAG_QUEUE_BYPASS;
	return ret;
}

static int nfqueue_tg_check(const struct xt_tgchk_param *par)
{
	const struct xt_NFQ_info_v3 *info = par->targinfo;
	u32 maxid;

	init_hashrandom(&jhash_initval);

	if (info->queues_total == 0) {
		pr_info_ratelimited("number of total queues is 0\n");
		return -EINVAL;
	}
	maxid = info->queues_total - 1 + info->queuenum;
	if (maxid > 0xffff) {
		pr_info_ratelimited("number of queues (%u) out of range (got %u)\n",
				    info->queues_total, maxid);
		return -ERANGE;
	}
	if (par->target->revision == 2 && info->flags > 1)
		return -EINVAL;
	if (par->target->revision == 3 && info->flags & ~NFQ_FLAG_MASK)
		return -EINVAL;

	return 0;
}

static unsigned int
nfqueue_tg_v3(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct xt_NFQ_info_v3 *info = par->targinfo;
	u32 queue = info->queuenum;
	int ret;

	if (info->queues_total > 1) {
		if (info->flags & NFQ_FLAG_CPU_FANOUT) {
			int cpu = smp_processor_id();

			queue = info->queuenum + cpu % info->queues_total;
		} else {
			queue = nfqueue_hash(skb, queue, info->queues_total,
					     xt_family(par), jhash_initval);
		}
	}

	ret = NF_QUEUE_NR(queue);
	if (info->flags & NFQ_FLAG_BYPASS)
		ret |= NF_VERDICT_FLAG_QUEUE_BYPASS;

	return ret;
}

static struct xt_target nfqueue_tg_reg[] __read_mostly = {
	{
		.name		= "NFQUEUE",
		.family		= NFPROTO_UNSPEC,
		.target		= nfqueue_tg,
		.targetsize	= sizeof(struct xt_NFQ_info),
		.me		= THIS_MODULE,
	},
	{
		.name		= "NFQUEUE",
		.revision	= 1,
		.family		= NFPROTO_UNSPEC,
		.checkentry	= nfqueue_tg_check,
		.target		= nfqueue_tg_v1,
		.targetsize	= sizeof(struct xt_NFQ_info_v1),
		.me		= THIS_MODULE,
	},
	{
		.name		= "NFQUEUE",
		.revision	= 2,
		.family		= NFPROTO_UNSPEC,
		.checkentry	= nfqueue_tg_check,
		.target		= nfqueue_tg_v2,
		.targetsize	= sizeof(struct xt_NFQ_info_v2),
		.me		= THIS_MODULE,
	},
	{
		.name		= "NFQUEUE",
		.revision	= 3,
		.family		= NFPROTO_UNSPEC,
		.checkentry	= nfqueue_tg_check,
		.target		= nfqueue_tg_v3,
		.targetsize	= sizeof(struct xt_NFQ_info_v3),
		.me		= THIS_MODULE,
	},
};

static int __init nfqueue_tg_init(void)
{
	return xt_register_targets(nfqueue_tg_reg, ARRAY_SIZE(nfqueue_tg_reg));
}

static void __exit nfqueue_tg_exit(void)
{
	xt_unregister_targets(nfqueue_tg_reg, ARRAY_SIZE(nfqueue_tg_reg));
}

module_init(nfqueue_tg_init);
module_exit(nfqueue_tg_exit);