net/ipv4/netfilter/nft_reject_ipv4.c

   1 /*
   2  * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
   3  * Copyright (c) 2013 Eric Leblond <eric@regit.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/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/netlink.h>
  16 #include <linux/netfilter.h>
  17 #include <linux/netfilter/nf_tables.h>
  18 #include <net/netfilter/nf_tables.h>
  19 #include <net/icmp.h>
  20 #include <net/netfilter/ipv4/nf_reject.h>
  21 #include <net/netfilter/nft_reject.h>
  22
  23 void nft_reject_ipv4_eval(const struct nft_expr *expr,
  24                           struct nft_data data[NFT_REG_MAX + 1],
  25                           const struct nft_pktinfo *pkt)
  26 {
  27         struct nft_reject *priv = nft_expr_priv(expr);
  28
  29         switch (priv->type) {
  30         case NFT_REJECT_ICMP_UNREACH:
  31                 nf_send_unreach(pkt->skb, priv->icmp_code);
  32                 break;
  33         case NFT_REJECT_TCP_RST:
  34                 nf_send_reset(pkt->skb, pkt->ops->hooknum);
  35                 break;
  36         }
  37
  38         data[NFT_REG_VERDICT].verdict = NF_DROP;
  39 }
  40 EXPORT_SYMBOL_GPL(nft_reject_ipv4_eval);
  41
  42 static struct nft_expr_type nft_reject_ipv4_type;
  43 static const struct nft_expr_ops nft_reject_ipv4_ops = {
  44         .type           = &nft_reject_ipv4_type,
  45         .size           = NFT_EXPR_SIZE(sizeof(struct nft_reject)),
  46         .eval           = nft_reject_ipv4_eval,
  47         .init           = nft_reject_init,
  48         .dump           = nft_reject_dump,
  49 };
  50
  51 static struct nft_expr_type nft_reject_ipv4_type __read_mostly = {
  52         .family         = NFPROTO_IPV4,
  53         .name           = "reject",
  54         .ops            = &nft_reject_ipv4_ops,
  55         .policy         = nft_reject_policy,
  56         .maxattr        = NFTA_REJECT_MAX,
  57         .owner          = THIS_MODULE,
  58 };
  59
  60 static int __init nft_reject_ipv4_module_init(void)
  61 {
  62         return nft_register_expr(&nft_reject_ipv4_type);
  63 }
  64
  65 static void __exit nft_reject_ipv4_module_exit(void)
  66 {
  67         nft_unregister_expr(&nft_reject_ipv4_type);
  68 }
  69
  70 module_init(nft_reject_ipv4_module_init);
  71 module_exit(nft_reject_ipv4_module_exit);
  72
  73 MODULE_LICENSE("GPL");
  74 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
  75 MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "reject");