1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
6 #include <linux/kernel.h>
7 #include <linux/init.h>
8 #include <linux/module.h>
9 #include <linux/netlink.h>
10 #include <linux/netfilter.h>
11 #include <linux/netfilter/nf_tables.h>
12 #include <net/netfilter/nf_tables.h>
13 #include <net/netfilter/ipv4/nf_dup_ipv4.h>
20 static void nft_dup_ipv4_eval(const struct nft_expr *expr,
21 struct nft_regs *regs,
22 const struct nft_pktinfo *pkt)
24 struct nft_dup_ipv4 *priv = nft_expr_priv(expr);
26 .s_addr = (__force __be32)regs->data[priv->sreg_addr],
28 int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1;
30 nf_dup_ipv4(nft_net(pkt), pkt->skb, nft_hook(pkt), &gw, oif);
33 static int nft_dup_ipv4_init(const struct nft_ctx *ctx,
34 const struct nft_expr *expr,
35 const struct nlattr * const tb[])
37 struct nft_dup_ipv4 *priv = nft_expr_priv(expr);
40 if (tb[NFTA_DUP_SREG_ADDR] == NULL)
43 err = nft_parse_register_load(tb[NFTA_DUP_SREG_ADDR], &priv->sreg_addr,
44 sizeof(struct in_addr));
48 if (tb[NFTA_DUP_SREG_DEV])
49 err = nft_parse_register_load(tb[NFTA_DUP_SREG_DEV],
50 &priv->sreg_dev, sizeof(int));
55 static int nft_dup_ipv4_dump(struct sk_buff *skb, const struct nft_expr *expr)
57 struct nft_dup_ipv4 *priv = nft_expr_priv(expr);
59 if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr))
62 nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev))
71 static struct nft_expr_type nft_dup_ipv4_type;
72 static const struct nft_expr_ops nft_dup_ipv4_ops = {
73 .type = &nft_dup_ipv4_type,
74 .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv4)),
75 .eval = nft_dup_ipv4_eval,
76 .init = nft_dup_ipv4_init,
77 .dump = nft_dup_ipv4_dump,
78 .reduce = NFT_REDUCE_READONLY,
81 static const struct nla_policy nft_dup_ipv4_policy[NFTA_DUP_MAX + 1] = {
82 [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 },
83 [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 },
86 static struct nft_expr_type nft_dup_ipv4_type __read_mostly = {
87 .family = NFPROTO_IPV4,
89 .ops = &nft_dup_ipv4_ops,
90 .policy = nft_dup_ipv4_policy,
91 .maxattr = NFTA_DUP_MAX,
95 static int __init nft_dup_ipv4_module_init(void)
97 return nft_register_expr(&nft_dup_ipv4_type);
100 static void __exit nft_dup_ipv4_module_exit(void)
102 nft_unregister_expr(&nft_dup_ipv4_type);
105 module_init(nft_dup_ipv4_module_init);
106 module_exit(nft_dup_ipv4_module_exit);
108 MODULE_LICENSE("GPL");
109 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
110 MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "dup");
111 MODULE_DESCRIPTION("IPv4 nftables packet duplication support");