nft_fib_netdev.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (c) 2017 Pablo M. Bermudo Garay <pablombg@gmail.com>
 4 *
 5 * This code is based on net/netfilter/nft_fib_inet.c, written by
 6 * Florian Westphal <fw@strlen.de>.
 7 */
 8
 9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/netlink.h>
13#include <linux/netfilter.h>
14#include <linux/netfilter/nf_tables.h>
15#include <net/netfilter/nf_tables_core.h>
16#include <net/netfilter/nf_tables.h>
17#include <net/ipv6.h>
18
19#include <net/netfilter/nft_fib.h>
20
21static void nft_fib_netdev_eval(const struct nft_expr *expr,
22				struct nft_regs *regs,
23				const struct nft_pktinfo *pkt)
24{
25	const struct nft_fib *priv = nft_expr_priv(expr);
26
27	switch (ntohs(pkt->skb->protocol)) {
28	case ETH_P_IP:
29		switch (priv->result) {
30		case NFT_FIB_RESULT_OIF:
31		case NFT_FIB_RESULT_OIFNAME:
32			return nft_fib4_eval(expr, regs, pkt);
33		case NFT_FIB_RESULT_ADDRTYPE:
34			return nft_fib4_eval_type(expr, regs, pkt);
35		}
36		break;
37	case ETH_P_IPV6:
38		if (!ipv6_mod_enabled())
39			break;
40		switch (priv->result) {
41		case NFT_FIB_RESULT_OIF:
42		case NFT_FIB_RESULT_OIFNAME:
43			return nft_fib6_eval(expr, regs, pkt);
44		case NFT_FIB_RESULT_ADDRTYPE:
45			return nft_fib6_eval_type(expr, regs, pkt);
46		}
47		break;
48	}
49
50	regs->verdict.code = NFT_BREAK;
51}
52
53static struct nft_expr_type nft_fib_netdev_type;
54static const struct nft_expr_ops nft_fib_netdev_ops = {
55	.type		= &nft_fib_netdev_type,
56	.size		= NFT_EXPR_SIZE(sizeof(struct nft_fib)),
57	.eval		= nft_fib_netdev_eval,
58	.init		= nft_fib_init,
59	.dump		= nft_fib_dump,
60	.validate	= nft_fib_validate,
61	.reduce		= nft_fib_reduce,
62};
63
64static struct nft_expr_type nft_fib_netdev_type __read_mostly = {
65	.family		= NFPROTO_NETDEV,
66	.name		= "fib",
67	.ops		= &nft_fib_netdev_ops,
68	.policy		= nft_fib_policy,
69	.maxattr	= NFTA_FIB_MAX,
70	.owner		= THIS_MODULE,
71};
72
73static int __init nft_fib_netdev_module_init(void)
74{
75	return nft_register_expr(&nft_fib_netdev_type);
76}
77
78static void __exit nft_fib_netdev_module_exit(void)
79{
80	nft_unregister_expr(&nft_fib_netdev_type);
81}
82
83module_init(nft_fib_netdev_module_init);
84module_exit(nft_fib_netdev_module_exit);
85
86MODULE_LICENSE("GPL");
87MODULE_AUTHOR("Pablo M. Bermudo Garay <pablombg@gmail.com>");
88MODULE_ALIAS_NFT_AF_EXPR(5, "fib");
89MODULE_DESCRIPTION("nftables netdev fib lookups support");