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
15 struct nft_dup_ipv6 {
16 u8 sreg_addr;
17 u8 sreg_dev;
18 };
19
nft_dup_ipv6_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)20 static 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 *)®s->data[priv->sreg_addr];
26 int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1;
27
28 nf_dup_ipv6(nft_net(pkt), pkt->skb, nft_hook(pkt), gw, oif);
29 }
30
nft_dup_ipv6_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])31 static 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(ctx, tb[NFTA_DUP_SREG_ADDR], &priv->sreg_addr,
42 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(ctx, tb[NFTA_DUP_SREG_DEV],
48 &priv->sreg_dev, sizeof(int));
49
50 return err;
51 }
52
nft_dup_ipv6_dump(struct sk_buff * skb,const struct nft_expr * expr,bool reset)53 static 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, NFTA_DUP_SREG_ADDR, priv->sreg_addr))
59 goto nla_put_failure;
60 if (priv->sreg_dev &&
61 nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev))
62 goto nla_put_failure;
63
64 return 0;
65
66 nla_put_failure:
67 return -1;
68 }
69
70 static struct nft_expr_type nft_dup_ipv6_type;
71 static 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
80 static 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
85 static 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
nft_dup_ipv6_module_init(void)94 static int __init nft_dup_ipv6_module_init(void)
95 {
96 return nft_register_expr(&nft_dup_ipv6_type);
97 }
98
nft_dup_ipv6_module_exit(void)99 static void __exit nft_dup_ipv6_module_exit(void)
100 {
101 nft_unregister_expr(&nft_dup_ipv6_type);
102 }
103
104 module_init(nft_dup_ipv6_module_init);
105 module_exit(nft_dup_ipv6_module_exit);
106
107 MODULE_LICENSE("GPL");
108 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
109 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup");
110 MODULE_DESCRIPTION("IPv6 nftables packet duplication support");
111