// SPDX-License-Identifier: GPL-2.0-only
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netfilter.h>
#include <linux/rhashtable.h>
#include <net/netfilter/nf_flow_table.h>
#include <net/netfilter/nf_tables.h>
#include <linux/if_vlan.h>
static unsigned int
nf_flow_offload_inet_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct vlan_ethhdr *veth;
__be16 proto;
switch (skb->protocol) {
case htons(ETH_P_8021Q):
if (!pskb_may_pull(skb, skb_mac_offset(skb) + sizeof(*veth)))
return NF_ACCEPT;
veth = (struct vlan_ethhdr *)skb_mac_header(skb);
proto = veth->h_vlan_encapsulated_proto;
break;
case htons(ETH_P_PPP_SES):
if (!nf_flow_pppoe_proto(skb, &proto))
return NF_ACCEPT;
break;
default:
proto = skb->protocol;
break;
}
switch (proto) {
case htons(ETH_P_IP):
return nf_flow_offload_ip_hook(priv, skb, state);
case htons(ETH_P_IPV6):
return nf_flow_offload_ipv6_hook(priv, skb, state);
}
return NF_ACCEPT;
}
static int nf_flow_rule_route_inet(struct net *net,
struct flow_offload *flow,
enum flow_offload_tuple_dir dir,
struct nf_flow_rule *flow_rule)
{
const struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
int err;
switch (flow_tuple->l3proto) {
case NFPROTO_IPV4:
err = nf_flow_rule_route_ipv4(net, flow, dir, flow_rule);
break;
case NFPROTO_IPV6:
err = nf_flow_rule_route_ipv6(net, flow, dir, flow_rule);
break;
default:
err = -1;
break;
}
return err;
}
static struct nf_flowtable_type flowtable_inet = {
.family = NFPROTO_INET,
.init = nf_flow_table_init,
.setup = nf_flow_table_offload_setup,
.action = nf_flow_rule_route_inet,
.free = nf_flow_table_free,
.hook = nf_flow_offload_inet_hook,
.owner = THIS_MODULE,
};
static struct nf_flowtable_type flowtable_ipv4 = {
.family = NFPROTO_IPV4,
.init = nf_flow_table_init,
.setup = nf_flow_table_offload_setup,
.action = nf_flow_rule_route_ipv4,
.free = nf_flow_table_free,
.hook = nf_flow_offload_ip_hook,
.owner = THIS_MODULE,
};
static struct nf_flowtable_type flowtable_ipv6 = {
.family = NFPROTO_IPV6,
.init = nf_flow_table_init,
.setup = nf_flow_table_offload_setup,
.action = nf_flow_rule_route_ipv6,
.free = nf_flow_table_free,
.hook = nf_flow_offload_ipv6_hook,
.owner = THIS_MODULE,
};
static int __init nf_flow_inet_module_init(void)
{
nft_register_flowtable_type(&flowtable_ipv4);
nft_register_flowtable_type(&flowtable_ipv6);
nft_register_flowtable_type(&flowtable_inet);
return 0;
}
static void __exit nf_flow_inet_module_exit(void)
{
nft_unregister_flowtable_type(&flowtable_inet);
nft_unregister_flowtable_type(&flowtable_ipv6);
nft_unregister_flowtable_type(&flowtable_ipv4);
}
module_init(nf_flow_inet_module_init);
module_exit(nf_flow_inet_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pablo Neira Ayuso <[email protected]>");
MODULE_ALIAS_NF_FLOWTABLE(AF_INET);
MODULE_ALIAS_NF_FLOWTABLE(AF_INET6);
MODULE_ALIAS_NF_FLOWTABLE(1); /* NFPROTO_INET */
MODULE_DESCRIPTION("Netfilter flow table mixed IPv4/IPv6 module");