summaryrefslogtreecommitdiff
path: root/net/netfilter/nft_counter.c
blob: c9743f78f21999ae01ed735a63c4e856e79cdc37 (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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 *
 * 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.
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/seqlock.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>

struct nft_counter {
	u64		bytes;
	u64		packets;
};

struct nft_counter_percpu {
	struct nft_counter	counter;
	struct u64_stats_sync	syncp;
};

struct nft_counter_percpu_priv {
	struct nft_counter_percpu __percpu *counter;
};

static void nft_counter_eval(const struct nft_expr *expr,
			     struct nft_regs *regs,
			     const struct nft_pktinfo *pkt)
{
	struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
	struct nft_counter_percpu *this_cpu;

	local_bh_disable();
	this_cpu = this_cpu_ptr(priv->counter);
	u64_stats_update_begin(&this_cpu->syncp);
	this_cpu->counter.bytes += pkt->skb->len;
	this_cpu->counter.packets++;
	u64_stats_update_end(&this_cpu->syncp);
	local_bh_enable();
}

static void nft_counter_fetch(const struct nft_counter_percpu __percpu *counter,
			      struct nft_counter *total)
{
	const struct nft_counter_percpu *cpu_stats;
	u64 bytes, packets;
	unsigned int seq;
	int cpu;

	memset(total, 0, sizeof(*total));
	for_each_possible_cpu(cpu) {
		cpu_stats = per_cpu_ptr(counter, cpu);
		do {
			seq	= u64_stats_fetch_begin_irq(&cpu_stats->syncp);
			bytes	= cpu_stats->counter.bytes;
			packets	= cpu_stats->counter.packets;
		} while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, seq));

		total->packets += packets;
		total->bytes += bytes;
	}
}

static int nft_counter_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
	struct nft_counter total;

	nft_counter_fetch(priv->counter, &total);

	if (nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(total.bytes)) ||
	    nla_put_be64(skb, NFTA_COUNTER_PACKETS, cpu_to_be64(total.packets)))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = {
	[NFTA_COUNTER_PACKETS]	= { .type = NLA_U64 },
	[NFTA_COUNTER_BYTES]	= { .type = NLA_U64 },
};

static int nft_counter_init(const struct nft_ctx *ctx,
			    const struct nft_expr *expr,
			    const struct nlattr * const tb[])
{
	struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
	struct nft_counter_percpu __percpu *cpu_stats;
	struct nft_counter_percpu *this_cpu;

	cpu_stats = netdev_alloc_pcpu_stats(struct nft_counter_percpu);
	if (cpu_stats == NULL)
		return -ENOMEM;

	preempt_disable();
	this_cpu = this_cpu_ptr(cpu_stats);
	if (tb[NFTA_COUNTER_PACKETS]) {
	        this_cpu->counter.packets =
			be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_PACKETS]));
	}
	if (tb[NFTA_COUNTER_BYTES]) {
		this_cpu->counter.bytes =
			be64_to_cpu(nla_get_be64(tb[NFTA_COUNTER_BYTES]));
	}
	preempt_enable();
	priv->counter = cpu_stats;
	return 0;
}

static void nft_counter_destroy(const struct nft_ctx *ctx,
				const struct nft_expr *expr)
{
	struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);

	free_percpu(priv->counter);
}

static int nft_counter_clone(struct nft_expr *dst, const struct nft_expr *src)
{
	struct nft_counter_percpu_priv *priv = nft_expr_priv(src);
	struct nft_counter_percpu_priv *priv_clone = nft_expr_priv(dst);
	struct nft_counter_percpu __percpu *cpu_stats;
	struct nft_counter_percpu *this_cpu;
	struct nft_counter total;

	nft_counter_fetch(priv->counter, &total);

	cpu_stats = __netdev_alloc_pcpu_stats(struct nft_counter_percpu,
					      GFP_ATOMIC);
	if (cpu_stats == NULL)
		return -ENOMEM;

	preempt_disable();
	this_cpu = this_cpu_ptr(cpu_stats);
	this_cpu->counter.packets = total.packets;
	this_cpu->counter.bytes = total.bytes;
	preempt_enable();

	priv_clone->counter = cpu_stats;
	return 0;
}

static struct nft_expr_type nft_counter_type;
static const struct nft_expr_ops nft_counter_ops = {
	.type		= &nft_counter_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_counter_percpu_priv)),
	.eval		= nft_counter_eval,
	.init		= nft_counter_init,
	.destroy	= nft_counter_destroy,
	.dump		= nft_counter_dump,
	.clone		= nft_counter_clone,
};

static struct nft_expr_type nft_counter_type __read_mostly = {
	.name		= "counter",
	.ops		= &nft_counter_ops,
	.policy		= nft_counter_policy,
	.maxattr	= NFTA_COUNTER_MAX,
	.flags		= NFT_EXPR_STATEFUL,
	.owner		= THIS_MODULE,
};

static int __init nft_counter_module_init(void)
{
	return nft_register_expr(&nft_counter_type);
}

static void __exit nft_counter_module_exit(void)
{
	nft_unregister_expr(&nft_counter_type);
}

module_init(nft_counter_module_init);
module_exit(nft_counter_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_EXPR("counter");