[mirror_ubuntu-bionic-kernel.git] / net / ipv4 / netfilter / nft_redir_ipv4.c

/*
 * Copyright (c) 2014 Arturo Borrero Gonzalez <arturo@debian.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.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_redirect.h>
#include <net/netfilter/nft_redir.h>

static void nft_redir_ipv4_eval(const struct nft_expr *expr,
				struct nft_regs *regs,
				const struct nft_pktinfo *pkt)
{
	struct nft_redir *priv = nft_expr_priv(expr);
	struct nf_nat_ipv4_multi_range_compat mr;

	memset(&mr, 0, sizeof(mr));
	if (priv->sreg_proto_min) {
		mr.range[0].min.all = (__force __be16)nft_reg_load16(
			&regs->data[priv->sreg_proto_min]);
		mr.range[0].max.all = (__force __be16)nft_reg_load16(
			&regs->data[priv->sreg_proto_max]);
		mr.range[0].flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
	}

	mr.range[0].flags |= priv->flags;

	regs->verdict.code = nf_nat_redirect_ipv4(pkt->skb, &mr, nft_hook(pkt));
}

static void
nft_redir_ipv4_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
{
	nf_ct_netns_put(ctx->net, NFPROTO_IPV4);
}

static struct nft_expr_type nft_redir_ipv4_type;
static const struct nft_expr_ops nft_redir_ipv4_ops = {
	.type		= &nft_redir_ipv4_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_redir)),
	.eval		= nft_redir_ipv4_eval,
	.init		= nft_redir_init,
	.destroy	= nft_redir_ipv4_destroy,
	.dump		= nft_redir_dump,
	.validate	= nft_redir_validate,
};

static struct nft_expr_type nft_redir_ipv4_type __read_mostly = {
	.family		= NFPROTO_IPV4,
	.name		= "redir",
	.ops		= &nft_redir_ipv4_ops,
	.policy		= nft_redir_policy,
	.maxattr	= NFTA_REDIR_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_redir_ipv4_module_init(void)
{
	return nft_register_expr(&nft_redir_ipv4_type);
}

static void __exit nft_redir_ipv4_module_exit(void)
{
	nft_unregister_expr(&nft_redir_ipv4_type);
}

module_init(nft_redir_ipv4_module_init);
module_exit(nft_redir_ipv4_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "redir");
Commit	Line	Data
e9105f1b	1	/*
cd727514	2	* Copyright (c) 2014 Arturo Borrero Gonzalez <arturo@debian.org>
e9105f1b AB	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/kernel.h>
	10	#include <linux/init.h>
	11	#include <linux/module.h>
	12	#include <linux/netlink.h>
	13	#include <linux/netfilter.h>
	14	#include <linux/netfilter/nf_tables.h>
	15	#include <net/netfilter/nf_tables.h>
	16	#include <net/netfilter/nf_nat.h>
b59eaf9e	17	#include <net/netfilter/nf_nat_redirect.h>
e9105f1b AB	18	#include <net/netfilter/nft_redir.h>
	19
	20	static void nft_redir_ipv4_eval(const struct nft_expr *expr,
a55e22e9	21	struct nft_regs *regs,
e9105f1b AB	22	const struct nft_pktinfo *pkt)
	23	{
	24	struct nft_redir *priv = nft_expr_priv(expr);
	25	struct nf_nat_ipv4_multi_range_compat mr;
e9105f1b AB	26
	27	memset(&mr, 0, sizeof(mr));
	28	if (priv->sreg_proto_min) {
10596608 LZ	29	mr.range[0].min.all = (__force __be16)nft_reg_load16(
	30	&regs->data[priv->sreg_proto_min]);
	31	mr.range[0].max.all = (__force __be16)nft_reg_load16(
	32	&regs->data[priv->sreg_proto_max]);
e9105f1b AB	33	mr.range[0].flags \|= NF_NAT_RANGE_PROTO_SPECIFIED;
	34	}
	35
	36	mr.range[0].flags \|= priv->flags;
	37
0e5a1c7e	38	regs->verdict.code = nf_nat_redirect_ipv4(pkt->skb, &mr, nft_hook(pkt));
e9105f1b AB	39	}
e9105f1b AB	40
20afd423 FW	41	static void
	42	nft_redir_ipv4_destroy(const struct nft_ctx ctx, const struct nft_expr expr)
	43	{
	44	nf_ct_netns_put(ctx->net, NFPROTO_IPV4);
	45	}
	46
e9105f1b AB	47	static struct nft_expr_type nft_redir_ipv4_type;
	48	static const struct nft_expr_ops nft_redir_ipv4_ops = {
	49	.type = &nft_redir_ipv4_type,
	50	.size = NFT_EXPR_SIZE(sizeof(struct nft_redir)),
	51	.eval = nft_redir_ipv4_eval,
	52	.init = nft_redir_init,
20afd423	53	.destroy = nft_redir_ipv4_destroy,
e9105f1b AB	54	.dump = nft_redir_dump,
	55	.validate = nft_redir_validate,
	56	};
	57
	58	static struct nft_expr_type nft_redir_ipv4_type __read_mostly = {
	59	.family = NFPROTO_IPV4,
	60	.name = "redir",
	61	.ops = &nft_redir_ipv4_ops,
	62	.policy = nft_redir_policy,
	63	.maxattr = NFTA_REDIR_MAX,
	64	.owner = THIS_MODULE,
	65	};
	66
	67	static int __init nft_redir_ipv4_module_init(void)
	68	{
	69	return nft_register_expr(&nft_redir_ipv4_type);
	70	}
	71
	72	static void __exit nft_redir_ipv4_module_exit(void)
	73	{
	74	nft_unregister_expr(&nft_redir_ipv4_type);
	75	}
	76
	77	module_init(nft_redir_ipv4_module_init);
	78	module_exit(nft_redir_ipv4_module_exit);
	79
	80	MODULE_LICENSE("GPL");
cd727514	81	MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
e9105f1b	82	MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "redir");