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(tb[NFTA_DUP_SREG_DEV], &priv->sreg_dev, 44 sizeof(int)); 45 } 46 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 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 bool nft_dup_netdev_offload_action(const struct nft_expr *expr) 71 { 72 return true; 73 } 74 75 static struct nft_expr_type nft_dup_netdev_type; 76 static const struct nft_expr_ops nft_dup_netdev_ops = { 77 .type = &nft_dup_netdev_type, 78 .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_netdev)), 79 .eval = nft_dup_netdev_eval, 80 .init = nft_dup_netdev_init, 81 .dump = nft_dup_netdev_dump, 82 .offload = nft_dup_netdev_offload, 83 .offload_action = nft_dup_netdev_offload_action, 84 }; 85 86 static struct nft_expr_type nft_dup_netdev_type __read_mostly = { 87 .family = NFPROTO_NETDEV, 88 .name = "dup", 89 .ops = &nft_dup_netdev_ops, 90 .policy = nft_dup_netdev_policy, 91 .maxattr = NFTA_DUP_MAX, 92 .owner = THIS_MODULE, 93 }; 94 95 static int __init nft_dup_netdev_module_init(void) 96 { 97 return nft_register_expr(&nft_dup_netdev_type); 98 } 99 100 static void __exit nft_dup_netdev_module_exit(void) 101 { 102 nft_unregister_expr(&nft_dup_netdev_type); 103 } 104 105 module_init(nft_dup_netdev_module_init); 106 module_exit(nft_dup_netdev_module_exit); 107 108 MODULE_LICENSE("GPL"); 109 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); 110 MODULE_ALIAS_NFT_AF_EXPR(5, "dup"); 111 MODULE_DESCRIPTION("nftables netdev packet duplication support"); 112