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
11 static unsigned int
nf_flow_offload_inet_hook(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)12 nf_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
nf_flow_rule_route_inet(struct net * net,struct flow_offload * flow,enum flow_offload_tuple_dir dir,struct nf_flow_rule * flow_rule)42 static 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
65 static 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
75 static 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
85 static 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
nf_flow_inet_module_init(void)95 static 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
nf_flow_inet_module_exit(void)104 static 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
111 module_init(nf_flow_inet_module_init);
112 module_exit(nf_flow_inet_module_exit);
113
114 MODULE_LICENSE("GPL");
115 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
116 MODULE_ALIAS_NF_FLOWTABLE(AF_INET);
117 MODULE_ALIAS_NF_FLOWTABLE(AF_INET6);
118 MODULE_ALIAS_NF_FLOWTABLE(1); /* NFPROTO_INET */
119 MODULE_DESCRIPTION("Netfilter flow table mixed IPv4/IPv6 module");
120