1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
4 */
5
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/ipv6/nf_dup_ipv6.h>
14
15struct nft_dup_ipv6 {
16 u8 sreg_addr;
17 u8 sreg_dev;
18};
19
20static void nft_dup_ipv6_eval(const struct nft_expr *expr,
21 struct nft_regs *regs,
22 const struct nft_pktinfo *pkt)
23{
24 struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
25 struct in6_addr *gw = (struct in6_addr *)&regs->data[priv->sreg_addr];
26 int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1;
27
28 nf_dup_ipv6(net: nft_net(pkt), skb: pkt->skb, hooknum: nft_hook(pkt), gw, oif);
29}
30
31static int nft_dup_ipv6_init(const struct nft_ctx *ctx,
32 const struct nft_expr *expr,
33 const struct nlattr * const tb[])
34{
35 struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
36 int err;
37
38 if (tb[NFTA_DUP_SREG_ADDR] == NULL)
39 return -EINVAL;
40
41 err = nft_parse_register_load(attr: tb[NFTA_DUP_SREG_ADDR], sreg: &priv->sreg_addr,
42 len: sizeof(struct in6_addr));
43 if (err < 0)
44 return err;
45
46 if (tb[NFTA_DUP_SREG_DEV])
47 err = nft_parse_register_load(attr: tb[NFTA_DUP_SREG_DEV],
48 sreg: &priv->sreg_dev, len: sizeof(int));
49
50 return err;
51}
52
53static int nft_dup_ipv6_dump(struct sk_buff *skb,
54 const struct nft_expr *expr, bool reset)
55{
56 struct nft_dup_ipv6 *priv = nft_expr_priv(expr);
57
58 if (nft_dump_register(skb, attr: NFTA_DUP_SREG_ADDR, reg: priv->sreg_addr))
59 goto nla_put_failure;
60 if (priv->sreg_dev &&
61 nft_dump_register(skb, attr: NFTA_DUP_SREG_DEV, reg: priv->sreg_dev))
62 goto nla_put_failure;
63
64 return 0;
65
66nla_put_failure:
67 return -1;
68}
69
70static struct nft_expr_type nft_dup_ipv6_type;
71static const struct nft_expr_ops nft_dup_ipv6_ops = {
72 .type = &nft_dup_ipv6_type,
73 .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv6)),
74 .eval = nft_dup_ipv6_eval,
75 .init = nft_dup_ipv6_init,
76 .dump = nft_dup_ipv6_dump,
77 .reduce = NFT_REDUCE_READONLY,
78};
79
80static const struct nla_policy nft_dup_ipv6_policy[NFTA_DUP_MAX + 1] = {
81 [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 },
82 [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 },
83};
84
85static struct nft_expr_type nft_dup_ipv6_type __read_mostly = {
86 .family = NFPROTO_IPV6,
87 .name = "dup",
88 .ops = &nft_dup_ipv6_ops,
89 .policy = nft_dup_ipv6_policy,
90 .maxattr = NFTA_DUP_MAX,
91 .owner = THIS_MODULE,
92};
93
94static int __init nft_dup_ipv6_module_init(void)
95{
96 return nft_register_expr(&nft_dup_ipv6_type);
97}
98
99static void __exit nft_dup_ipv6_module_exit(void)
100{
101 nft_unregister_expr(&nft_dup_ipv6_type);
102}
103
104module_init(nft_dup_ipv6_module_init);
105module_exit(nft_dup_ipv6_module_exit);
106
107MODULE_LICENSE("GPL");
108MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
109MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup");
110MODULE_DESCRIPTION("IPv6 nftables packet duplication support");
111

source code of linux/net/ipv6/netfilter/nft_dup_ipv6.c