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(const struct nf_hook_ops *ops,
  19                   struct sk_buff *skb,
  20                   const struct net_device *in,
  21                   const struct net_device *out,
  22                   int (*okfn)(struct sk_buff *))
  23 {
  24         struct nft_pktinfo pkt;
  25
  26         nft_set_pktinfo(&pkt, ops, skb, in, out);
  27
  28         return nft_do_chain(&pkt, ops);
  29 }
  30
  31 static struct nft_af_info nft_af_arp __read_mostly = {
  32         .family         = NFPROTO_ARP,
  33         .nhooks         = NF_ARP_NUMHOOKS,
  34         .owner          = THIS_MODULE,
  35         .nops           = 1,
  36         .hooks          = {
  37                 [NF_ARP_IN]             = nft_do_chain_arp,
  38                 [NF_ARP_OUT]            = nft_do_chain_arp,
  39                 [NF_ARP_FORWARD]        = nft_do_chain_arp,
  40         },
  41 };
  42
  43 static int nf_tables_arp_init_net(struct net *net)
  44 {
  45         net->nft.arp = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
  46         if (net->nft.arp== NULL)
  47                 return -ENOMEM;
  48
  49         memcpy(net->nft.arp, &nft_af_arp, sizeof(nft_af_arp));
  50
  51         if (nft_register_afinfo(net, net->nft.arp) < 0)
  52                 goto err;
  53
  54         return 0;
  55 err:
  56         kfree(net->nft.arp);
  57         return -ENOMEM;
  58 }
  59
  60 static void nf_tables_arp_exit_net(struct net *net)
  61 {
  62         nft_unregister_afinfo(net->nft.arp);
  63         kfree(net->nft.arp);
  64 }
  65
  66 static struct pernet_operations nf_tables_arp_net_ops = {
  67         .init   = nf_tables_arp_init_net,
  68         .exit   = nf_tables_arp_exit_net,
  69 };
  70
  71 static const struct nf_chain_type filter_arp = {
  72         .name           = "filter",
  73         .type           = NFT_CHAIN_T_DEFAULT,
  74         .family         = NFPROTO_ARP,
  75         .owner          = THIS_MODULE,
  76         .hook_mask      = (1 << NF_ARP_IN) |
  77                           (1 << NF_ARP_OUT) |
  78                           (1 << NF_ARP_FORWARD),
  79 };
  80
  81 static int __init nf_tables_arp_init(void)
  82 {
  83         int ret;
  84
  85         nft_register_chain_type(&filter_arp);
  86         ret = register_pernet_subsys(&nf_tables_arp_net_ops);
  87         if (ret < 0)
  88                 nft_unregister_chain_type(&filter_arp);
  89
  90         return ret;
  91 }
  92
  93 static void __exit nf_tables_arp_exit(void)
  94 {
  95         unregister_pernet_subsys(&nf_tables_arp_net_ops);
  96         nft_unregister_chain_type(&filter_arp);
  97 }
  98
  99 module_init(nf_tables_arp_init);
 100 module_exit(nf_tables_arp_exit);
 101
 102 MODULE_LICENSE("GPL");
 103 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 104 MODULE_ALIAS_NFT_FAMILY(3); /* NFPROTO_ARP */