net/netfilter/nf_flow_table_inet.c

   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
  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                 proto = nf_flow_pppoe_proto(skb);
  25                 break;
  26         default:
  27                 proto = skb->protocol;
  28                 break;
  29         }
  30
  31         switch (proto) {
  32         case htons(ETH_P_IP):
  33                 return nf_flow_offload_ip_hook(priv, skb, state);
  34         case htons(ETH_P_IPV6):
  35                 return nf_flow_offload_ipv6_hook(priv, skb, state);
  36         }
  37
  38         return NF_ACCEPT;
  39 }
  40
  41 static int nf_flow_rule_route_inet(struct net *net,
  42                                    struct flow_offload *flow,
  43                                    enum flow_offload_tuple_dir dir,
  44                                    struct nf_flow_rule *flow_rule)
  45 {
  46         const struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
  47         int err;
  48
  49         switch (flow_tuple->l3proto) {
  50         case NFPROTO_IPV4:
  51                 err = nf_flow_rule_route_ipv4(net, flow, dir, flow_rule);
  52                 break;
  53         case NFPROTO_IPV6:
  54                 err = nf_flow_rule_route_ipv6(net, flow, dir, flow_rule);
  55                 break;
  56         default:
  57                 err = -1;
  58                 break;
  59         }
  60
  61         return err;
  62 }
  63
  64 static struct nf_flowtable_type flowtable_inet = {
  65         .family         = NFPROTO_INET,
  66         .init           = nf_flow_table_init,
  67         .setup          = nf_flow_table_offload_setup,
  68         .action         = nf_flow_rule_route_inet,
  69         .free           = nf_flow_table_free,
  70         .hook           = nf_flow_offload_inet_hook,
  71         .owner          = THIS_MODULE,
  72 };
  73
  74 static struct nf_flowtable_type flowtable_ipv4 = {
  75         .family         = NFPROTO_IPV4,
  76         .init           = nf_flow_table_init,
  77         .setup          = nf_flow_table_offload_setup,
  78         .action         = nf_flow_rule_route_ipv4,
  79         .free           = nf_flow_table_free,
  80         .hook           = nf_flow_offload_ip_hook,
  81         .owner          = THIS_MODULE,
  82 };
  83
  84 static struct nf_flowtable_type flowtable_ipv6 = {
  85         .family         = NFPROTO_IPV6,
  86         .init           = nf_flow_table_init,
  87         .setup          = nf_flow_table_offload_setup,
  88         .action         = nf_flow_rule_route_ipv6,
  89         .free           = nf_flow_table_free,
  90         .hook           = nf_flow_offload_ipv6_hook,
  91         .owner          = THIS_MODULE,
  92 };
  93
  94 static int __init nf_flow_inet_module_init(void)
  95 {
  96         nft_register_flowtable_type(&flowtable_ipv4);
  97         nft_register_flowtable_type(&flowtable_ipv6);
  98         nft_register_flowtable_type(&flowtable_inet);
  99
 100         return 0;
 101 }
 102
 103 static void __exit nf_flow_inet_module_exit(void)
 104 {
 105         nft_unregister_flowtable_type(&flowtable_inet);
 106         nft_unregister_flowtable_type(&flowtable_ipv6);
 107         nft_unregister_flowtable_type(&flowtable_ipv4);
 108 }
 109
 110 module_init(nf_flow_inet_module_init);
 111 module_exit(nf_flow_inet_module_exit);
 112
 113 MODULE_LICENSE("GPL");
 114 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 115 MODULE_ALIAS_NF_FLOWTABLE(AF_INET);
 116 MODULE_ALIAS_NF_FLOWTABLE(AF_INET6);
 117 MODULE_ALIAS_NF_FLOWTABLE(1); /* NFPROTO_INET */
 118 MODULE_DESCRIPTION("Netfilter flow table mixed IPv4/IPv6 module");