1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
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>
13 #include <linux/ipv6.h>
14 #include <net/netfilter/nf_tables.h>
15 #include <net/netfilter/nf_tables_offload.h>
16 #include <net/netfilter/nf_dup_netdev.h>
17 #include <net/neighbour.h>
20 struct nft_fwd_netdev {
24 static void nft_fwd_netdev_eval(const struct nft_expr *expr,
25 struct nft_regs *regs,
26 const struct nft_pktinfo *pkt)
28 struct nft_fwd_netdev *priv = nft_expr_priv(expr);
29 int oif = regs->data[priv->sreg_dev];
31 /* This is used by ifb only. */
32 skb_set_redirected(pkt->skb, true);
34 nf_fwd_netdev_egress(pkt, oif);
35 regs->verdict.code = NF_STOLEN;
38 static const struct nla_policy nft_fwd_netdev_policy[NFTA_FWD_MAX + 1] = {
39 [NFTA_FWD_SREG_DEV] = { .type = NLA_U32 },
40 [NFTA_FWD_SREG_ADDR] = { .type = NLA_U32 },
41 [NFTA_FWD_NFPROTO] = { .type = NLA_U32 },
44 static int nft_fwd_netdev_init(const struct nft_ctx *ctx,
45 const struct nft_expr *expr,
46 const struct nlattr * const tb[])
48 struct nft_fwd_netdev *priv = nft_expr_priv(expr);
50 if (tb[NFTA_FWD_SREG_DEV] == NULL)
53 return nft_parse_register_load(tb[NFTA_FWD_SREG_DEV], &priv->sreg_dev,
57 static int nft_fwd_netdev_dump(struct sk_buff *skb, const struct nft_expr *expr)
59 struct nft_fwd_netdev *priv = nft_expr_priv(expr);
61 if (nft_dump_register(skb, NFTA_FWD_SREG_DEV, priv->sreg_dev))
70 static int nft_fwd_netdev_offload(struct nft_offload_ctx *ctx,
71 struct nft_flow_rule *flow,
72 const struct nft_expr *expr)
74 const struct nft_fwd_netdev *priv = nft_expr_priv(expr);
75 int oif = ctx->regs[priv->sreg_dev].data.data[0];
77 return nft_fwd_dup_netdev_offload(ctx, flow, FLOW_ACTION_REDIRECT, oif);
80 struct nft_fwd_neigh {
86 static void nft_fwd_neigh_eval(const struct nft_expr *expr,
87 struct nft_regs *regs,
88 const struct nft_pktinfo *pkt)
90 struct nft_fwd_neigh *priv = nft_expr_priv(expr);
91 void *addr = ®s->data[priv->sreg_addr];
92 int oif = regs->data[priv->sreg_dev];
93 unsigned int verdict = NF_STOLEN;
94 struct sk_buff *skb = pkt->skb;
95 struct net_device *dev;
98 switch (priv->nfproto) {
102 if (skb->protocol != htons(ETH_P_IP)) {
106 if (skb_try_make_writable(skb, sizeof(*iph))) {
111 ip_decrease_ttl(iph);
112 neigh_table = NEIGH_ARP_TABLE;
116 struct ipv6hdr *ip6h;
118 if (skb->protocol != htons(ETH_P_IPV6)) {
122 if (skb_try_make_writable(skb, sizeof(*ip6h))) {
126 ip6h = ipv6_hdr(skb);
128 neigh_table = NEIGH_ND_TABLE;
136 dev = dev_get_by_index_rcu(nft_net(pkt), oif);
142 neigh_xmit(neigh_table, dev, addr, skb);
144 regs->verdict.code = verdict;
147 static int nft_fwd_neigh_init(const struct nft_ctx *ctx,
148 const struct nft_expr *expr,
149 const struct nlattr * const tb[])
151 struct nft_fwd_neigh *priv = nft_expr_priv(expr);
152 unsigned int addr_len;
155 if (!tb[NFTA_FWD_SREG_DEV] ||
156 !tb[NFTA_FWD_SREG_ADDR] ||
157 !tb[NFTA_FWD_NFPROTO])
160 priv->nfproto = ntohl(nla_get_be32(tb[NFTA_FWD_NFPROTO]));
162 switch (priv->nfproto) {
164 addr_len = sizeof(struct in_addr);
167 addr_len = sizeof(struct in6_addr);
173 err = nft_parse_register_load(tb[NFTA_FWD_SREG_DEV], &priv->sreg_dev,
178 return nft_parse_register_load(tb[NFTA_FWD_SREG_ADDR], &priv->sreg_addr,
182 static int nft_fwd_neigh_dump(struct sk_buff *skb, const struct nft_expr *expr)
184 struct nft_fwd_neigh *priv = nft_expr_priv(expr);
186 if (nft_dump_register(skb, NFTA_FWD_SREG_DEV, priv->sreg_dev) ||
187 nft_dump_register(skb, NFTA_FWD_SREG_ADDR, priv->sreg_addr) ||
188 nla_put_be32(skb, NFTA_FWD_NFPROTO, htonl(priv->nfproto)))
189 goto nla_put_failure;
197 static int nft_fwd_validate(const struct nft_ctx *ctx,
198 const struct nft_expr *expr,
199 const struct nft_data **data)
201 return nft_chain_validate_hooks(ctx->chain, (1 << NF_NETDEV_INGRESS));
204 static struct nft_expr_type nft_fwd_netdev_type;
205 static const struct nft_expr_ops nft_fwd_neigh_netdev_ops = {
206 .type = &nft_fwd_netdev_type,
207 .size = NFT_EXPR_SIZE(sizeof(struct nft_fwd_neigh)),
208 .eval = nft_fwd_neigh_eval,
209 .init = nft_fwd_neigh_init,
210 .dump = nft_fwd_neigh_dump,
211 .validate = nft_fwd_validate,
214 static const struct nft_expr_ops nft_fwd_netdev_ops = {
215 .type = &nft_fwd_netdev_type,
216 .size = NFT_EXPR_SIZE(sizeof(struct nft_fwd_netdev)),
217 .eval = nft_fwd_netdev_eval,
218 .init = nft_fwd_netdev_init,
219 .dump = nft_fwd_netdev_dump,
220 .validate = nft_fwd_validate,
221 .offload = nft_fwd_netdev_offload,
224 static const struct nft_expr_ops *
225 nft_fwd_select_ops(const struct nft_ctx *ctx,
226 const struct nlattr * const tb[])
228 if (tb[NFTA_FWD_SREG_ADDR])
229 return &nft_fwd_neigh_netdev_ops;
230 if (tb[NFTA_FWD_SREG_DEV])
231 return &nft_fwd_netdev_ops;
233 return ERR_PTR(-EOPNOTSUPP);
236 static struct nft_expr_type nft_fwd_netdev_type __read_mostly = {
237 .family = NFPROTO_NETDEV,
239 .select_ops = nft_fwd_select_ops,
240 .policy = nft_fwd_netdev_policy,
241 .maxattr = NFTA_FWD_MAX,
242 .owner = THIS_MODULE,
245 static int __init nft_fwd_netdev_module_init(void)
247 return nft_register_expr(&nft_fwd_netdev_type);
250 static void __exit nft_fwd_netdev_module_exit(void)
252 nft_unregister_expr(&nft_fwd_netdev_type);
255 module_init(nft_fwd_netdev_module_init);
256 module_exit(nft_fwd_netdev_module_exit);
258 MODULE_LICENSE("GPL");
259 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
260 MODULE_ALIAS_NFT_AF_EXPR(5, "fwd");