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/nf_tables_offload.h> |
14 | #include <net/netfilter/nf_dup_netdev.h> |
15 | |
16 | struct nft_dup_netdev { |
17 | u8 sreg_dev; |
18 | }; |
19 | |
20 | static void nft_dup_netdev_eval(const struct nft_expr *expr, |
21 | struct nft_regs *regs, |
22 | const struct nft_pktinfo *pkt) |
23 | { |
24 | struct nft_dup_netdev *priv = nft_expr_priv(expr); |
25 | int oif = regs->data[priv->sreg_dev]; |
26 | |
27 | nf_dup_netdev_egress(pkt, oif); |
28 | } |
29 | |
30 | static const struct nla_policy nft_dup_netdev_policy[NFTA_DUP_MAX + 1] = { |
31 | [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 }, |
32 | }; |
33 | |
34 | static int nft_dup_netdev_init(const struct nft_ctx *ctx, |
35 | const struct nft_expr *expr, |
36 | const struct nlattr * const tb[]) |
37 | { |
38 | struct nft_dup_netdev *priv = nft_expr_priv(expr); |
39 | |
40 | if (tb[NFTA_DUP_SREG_DEV] == NULL) |
41 | return -EINVAL; |
42 | |
43 | return nft_parse_register_load(attr: tb[NFTA_DUP_SREG_DEV], sreg: &priv->sreg_dev, |
44 | len: sizeof(int)); |
45 | } |
46 | |
47 | static int nft_dup_netdev_dump(struct sk_buff *skb, |
48 | const struct nft_expr *expr, bool reset) |
49 | { |
50 | struct nft_dup_netdev *priv = nft_expr_priv(expr); |
51 | |
52 | if (nft_dump_register(skb, attr: NFTA_DUP_SREG_DEV, reg: priv->sreg_dev)) |
53 | goto nla_put_failure; |
54 | |
55 | return 0; |
56 | |
57 | nla_put_failure: |
58 | return -1; |
59 | } |
60 | |
61 | static int nft_dup_netdev_offload(struct nft_offload_ctx *ctx, |
62 | struct nft_flow_rule *flow, |
63 | const struct nft_expr *expr) |
64 | { |
65 | const struct nft_dup_netdev *priv = nft_expr_priv(expr); |
66 | int oif = ctx->regs[priv->sreg_dev].data.data[0]; |
67 | |
68 | return nft_fwd_dup_netdev_offload(ctx, flow, id: FLOW_ACTION_MIRRED, oif); |
69 | } |
70 | |
71 | static bool nft_dup_netdev_offload_action(const struct nft_expr *expr) |
72 | { |
73 | return true; |
74 | } |
75 | |
76 | static struct nft_expr_type nft_dup_netdev_type; |
77 | static const struct nft_expr_ops nft_dup_netdev_ops = { |
78 | .type = &nft_dup_netdev_type, |
79 | .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_netdev)), |
80 | .eval = nft_dup_netdev_eval, |
81 | .init = nft_dup_netdev_init, |
82 | .dump = nft_dup_netdev_dump, |
83 | .reduce = NFT_REDUCE_READONLY, |
84 | .offload = nft_dup_netdev_offload, |
85 | .offload_action = nft_dup_netdev_offload_action, |
86 | }; |
87 | |
88 | static struct nft_expr_type nft_dup_netdev_type __read_mostly = { |
89 | .family = NFPROTO_NETDEV, |
90 | .name = "dup" , |
91 | .ops = &nft_dup_netdev_ops, |
92 | .policy = nft_dup_netdev_policy, |
93 | .maxattr = NFTA_DUP_MAX, |
94 | .owner = THIS_MODULE, |
95 | }; |
96 | |
97 | static int __init nft_dup_netdev_module_init(void) |
98 | { |
99 | return nft_register_expr(&nft_dup_netdev_type); |
100 | } |
101 | |
102 | static void __exit nft_dup_netdev_module_exit(void) |
103 | { |
104 | nft_unregister_expr(&nft_dup_netdev_type); |
105 | } |
106 | |
107 | module_init(nft_dup_netdev_module_init); |
108 | module_exit(nft_dup_netdev_module_exit); |
109 | |
110 | MODULE_LICENSE("GPL" ); |
111 | MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>" ); |
112 | MODULE_ALIAS_NFT_AF_EXPR(5, "dup" ); |
113 | MODULE_DESCRIPTION("nftables netdev packet duplication support" ); |
114 | |