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                 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
  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
  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
 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");