net/ipv4/netfilter/nf_tables_arp.c

   1 /*
   2  * Copyright (c) 2008-2010 Patrick McHardy <kaber@trash.net>
   3  * Copyright (c) 2013 Pablo Neira Ayuso <pablo@netfilter.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Development of this code funded by Astaro AG (http://www.astaro.com/)
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/netfilter_arp.h>
  15 #include <net/netfilter/nf_tables.h>
  16
  17 static unsigned int
  18 nft_do_chain_arp(void *priv,
  19                   struct sk_buff *skb,
  20                   const struct nf_hook_state *state)
  21 {
  22         struct nft_pktinfo pkt;
  23
  24         nft_set_pktinfo_unspec(&pkt, skb, state);
  25
  26         return nft_do_chain(&pkt, priv);
  27 }
  28
  29 static struct nft_af_info nft_af_arp __read_mostly = {
  30         .family         = NFPROTO_ARP,
  31         .nhooks         = NF_ARP_NUMHOOKS,
  32         .owner          = THIS_MODULE,
  33         .nops           = 1,
  34         .hooks          = {
  35                 [NF_ARP_IN]             = nft_do_chain_arp,
  36                 [NF_ARP_OUT]            = nft_do_chain_arp,
  37                 [NF_ARP_FORWARD]        = nft_do_chain_arp,
  38         },
  39 };
  40
  41 static int nf_tables_arp_init_net(struct net *net)
  42 {
  43         net->nft.arp = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
  44         if (net->nft.arp== NULL)
  45                 return -ENOMEM;
  46
  47         memcpy(net->nft.arp, &nft_af_arp, sizeof(nft_af_arp));
  48
  49         if (nft_register_afinfo(net, net->nft.arp) < 0)
  50                 goto err;
  51
  52         return 0;
  53 err:
  54         kfree(net->nft.arp);
  55         return -ENOMEM;
  56 }
  57
  58 static void nf_tables_arp_exit_net(struct net *net)
  59 {
  60         nft_unregister_afinfo(net, net->nft.arp);
  61         kfree(net->nft.arp);
  62 }
  63
  64 static struct pernet_operations nf_tables_arp_net_ops = {
  65         .init   = nf_tables_arp_init_net,
  66         .exit   = nf_tables_arp_exit_net,
  67 };
  68
  69 static const struct nf_chain_type filter_arp = {
  70         .name           = "filter",
  71         .type           = NFT_CHAIN_T_DEFAULT,
  72         .family         = NFPROTO_ARP,
  73         .owner          = THIS_MODULE,
  74         .hook_mask      = (1 << NF_ARP_IN) |
  75                           (1 << NF_ARP_OUT) |
  76                           (1 << NF_ARP_FORWARD),
  77 };
  78
  79 static int __init nf_tables_arp_init(void)
  80 {
  81         int ret;
  82
  83         ret = nft_register_chain_type(&filter_arp);
  84         if (ret < 0)
  85                 return ret;
  86
  87         ret = register_pernet_subsys(&nf_tables_arp_net_ops);
  88         if (ret < 0)
  89                 nft_unregister_chain_type(&filter_arp);
  90
  91         return ret;
  92 }
  93
  94 static void __exit nf_tables_arp_exit(void)
  95 {
  96         unregister_pernet_subsys(&nf_tables_arp_net_ops);
  97         nft_unregister_chain_type(&filter_arp);
  98 }
  99
 100 module_init(nf_tables_arp_init);
 101 module_exit(nf_tables_arp_exit);
 102
 103 MODULE_LICENSE("GPL");
 104 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 105 MODULE_ALIAS_NFT_FAMILY(3); /* NFPROTO_ARP */