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
nft_dup_netdev_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)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
nft_dup_netdev_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])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(tb[NFTA_DUP_SREG_DEV], &priv->sreg_dev,
44 sizeof(int));
45 }
46
nft_dup_netdev_dump(struct sk_buff * skb,const struct nft_expr * expr)47 static int nft_dup_netdev_dump(struct sk_buff *skb, const struct nft_expr *expr)
48 {
49 struct nft_dup_netdev *priv = nft_expr_priv(expr);
50
51 if (nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev))
52 goto nla_put_failure;
53
54 return 0;
55
56 nla_put_failure:
57 return -1;
58 }
59
nft_dup_netdev_offload(struct nft_offload_ctx * ctx,struct nft_flow_rule * flow,const struct nft_expr * expr)60 static int nft_dup_netdev_offload(struct nft_offload_ctx *ctx,
61 struct nft_flow_rule *flow,
62 const struct nft_expr *expr)
63 {
64 const struct nft_dup_netdev *priv = nft_expr_priv(expr);
65 int oif = ctx->regs[priv->sreg_dev].data.data[0];
66
67 return nft_fwd_dup_netdev_offload(ctx, flow, FLOW_ACTION_MIRRED, oif);
68 }
69
70 static struct nft_expr_type nft_dup_netdev_type;
71 static const struct nft_expr_ops nft_dup_netdev_ops = {
72 .type = &nft_dup_netdev_type,
73 .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_netdev)),
74 .eval = nft_dup_netdev_eval,
75 .init = nft_dup_netdev_init,
76 .dump = nft_dup_netdev_dump,
77 .offload = nft_dup_netdev_offload,
78 };
79
80 static struct nft_expr_type nft_dup_netdev_type __read_mostly = {
81 .family = NFPROTO_NETDEV,
82 .name = "dup",
83 .ops = &nft_dup_netdev_ops,
84 .policy = nft_dup_netdev_policy,
85 .maxattr = NFTA_DUP_MAX,
86 .owner = THIS_MODULE,
87 };
88
nft_dup_netdev_module_init(void)89 static int __init nft_dup_netdev_module_init(void)
90 {
91 return nft_register_expr(&nft_dup_netdev_type);
92 }
93
nft_dup_netdev_module_exit(void)94 static void __exit nft_dup_netdev_module_exit(void)
95 {
96 nft_unregister_expr(&nft_dup_netdev_type);
97 }
98
99 module_init(nft_dup_netdev_module_init);
100 module_exit(nft_dup_netdev_module_exit);
101
102 MODULE_LICENSE("GPL");
103 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
104 MODULE_ALIAS_NFT_AF_EXPR(5, "dup");
105 MODULE_DESCRIPTION("nftables netdev packet duplication support");
106
