1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/kernel.h>
3#include <linux/init.h>
4#include <linux/module.h>
5#include <linux/netfilter.h>
6#include <linux/rhashtable.h>
7#include <net/netfilter/nf_flow_table.h>
8#include <net/netfilter/nf_tables.h>
9#include <linux/if_vlan.h>
10
11static unsigned int
12nf_flow_offload_inet_hook(void *priv, struct sk_buff *skb,
13			  const struct nf_hook_state *state)
14{
15	struct vlan_ethhdr *veth;
16	__be16 proto;
17
18	switch (skb->protocol) {
19	case htons(ETH_P_8021Q):
20		veth = (struct vlan_ethhdr *)skb_mac_header(skb);
21		proto = veth->h_vlan_encapsulated_proto;
22		break;
23	case htons(ETH_P_PPP_SES):
24		if (!nf_flow_pppoe_proto(skb, &proto))
25			return NF_ACCEPT;
26		break;
27	default:
28		proto = skb->protocol;
29		break;
30	}
31
32	switch (proto) {
33	case htons(ETH_P_IP):
34		return nf_flow_offload_ip_hook(priv, skb, state);
35	case htons(ETH_P_IPV6):
36		return nf_flow_offload_ipv6_hook(priv, skb, state);
37	}
38
39	return NF_ACCEPT;
40}
41
42static int nf_flow_rule_route_inet(struct net *net,
43				   struct flow_offload *flow,
44				   enum flow_offload_tuple_dir dir,
45				   struct nf_flow_rule *flow_rule)
46{
47	const struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
48	int err;
49
50	switch (flow_tuple->l3proto) {
51	case NFPROTO_IPV4:
52		err = nf_flow_rule_route_ipv4(net, flow, dir, flow_rule);
53		break;
54	case NFPROTO_IPV6:
55		err = nf_flow_rule_route_ipv6(net, flow, dir, flow_rule);
56		break;
57	default:
58		err = -1;
59		break;
60	}
61
62	return err;
63}
64
65static struct nf_flowtable_type flowtable_inet = {
66	.family		= NFPROTO_INET,
67	.init		= nf_flow_table_init,
68	.setup		= nf_flow_table_offload_setup,
69	.action		= nf_flow_rule_route_inet,
70	.free		= nf_flow_table_free,
71	.hook		= nf_flow_offload_inet_hook,
72	.owner		= THIS_MODULE,
73};
74
75static struct nf_flowtable_type flowtable_ipv4 = {
76	.family		= NFPROTO_IPV4,
77	.init		= nf_flow_table_init,
78	.setup		= nf_flow_table_offload_setup,
79	.action		= nf_flow_rule_route_ipv4,
80	.free		= nf_flow_table_free,
81	.hook		= nf_flow_offload_ip_hook,
82	.owner		= THIS_MODULE,
83};
84
85static struct nf_flowtable_type flowtable_ipv6 = {
86	.family		= NFPROTO_IPV6,
87	.init		= nf_flow_table_init,
88	.setup		= nf_flow_table_offload_setup,
89	.action		= nf_flow_rule_route_ipv6,
90	.free		= nf_flow_table_free,
91	.hook		= nf_flow_offload_ipv6_hook,
92	.owner		= THIS_MODULE,
93};
94
95static int __init nf_flow_inet_module_init(void)
96{
97	nft_register_flowtable_type(&flowtable_ipv4);
98	nft_register_flowtable_type(&flowtable_ipv6);
99	nft_register_flowtable_type(&flowtable_inet);
100
101	return 0;
102}
103
104static void __exit nf_flow_inet_module_exit(void)
105{
106	nft_unregister_flowtable_type(&flowtable_inet);
107	nft_unregister_flowtable_type(&flowtable_ipv6);
108	nft_unregister_flowtable_type(&flowtable_ipv4);
109}
110
111module_init(nf_flow_inet_module_init);
112module_exit(nf_flow_inet_module_exit);
113
114MODULE_LICENSE("GPL");
115MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
116MODULE_ALIAS_NF_FLOWTABLE(AF_INET);
117MODULE_ALIAS_NF_FLOWTABLE(AF_INET6);
118MODULE_ALIAS_NF_FLOWTABLE(1); /* NFPROTO_INET */
119MODULE_DESCRIPTION("Netfilter flow table mixed IPv4/IPv6 module");
120