1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 * Copyright (c) 2013 Eric Leblond <eric@regit.org>
5 *
6 * Development of this code funded by Astaro AG (http://www.astaro.com/)
7 */
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/netlink.h>
13#include <linux/netfilter.h>
14#include <linux/netfilter/nf_tables.h>
15#include <net/netfilter/nf_tables.h>
16#include <net/netfilter/ipv4/nf_reject.h>
17#include <net/netfilter/nft_reject.h>
18
19static void nft_reject_ipv4_eval(const struct nft_expr *expr,
20 struct nft_regs *regs,
21 const struct nft_pktinfo *pkt)
22{
23 struct nft_reject *priv = nft_expr_priv(expr);
24
25 switch (priv->type) {
26 case NFT_REJECT_ICMP_UNREACH:
27 nf_send_unreach(skb_in: pkt->skb, code: priv->icmp_code, hook: nft_hook(pkt));
28 break;
29 case NFT_REJECT_TCP_RST:
30 nf_send_reset(net: nft_net(pkt), nft_sk(pkt), oldskb: pkt->skb,
31 hook: nft_hook(pkt));
32 break;
33 default:
34 break;
35 }
36
37 regs->verdict.code = NF_DROP;
38}
39
40static struct nft_expr_type nft_reject_ipv4_type;
41static const struct nft_expr_ops nft_reject_ipv4_ops = {
42 .type = &nft_reject_ipv4_type,
43 .size = NFT_EXPR_SIZE(sizeof(struct nft_reject)),
44 .eval = nft_reject_ipv4_eval,
45 .init = nft_reject_init,
46 .dump = nft_reject_dump,
47 .validate = nft_reject_validate,
48 .reduce = NFT_REDUCE_READONLY,
49};
50
51static 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
60static int __init nft_reject_ipv4_module_init(void)
61{
62 return nft_register_expr(&nft_reject_ipv4_type);
63}
64
65static void __exit nft_reject_ipv4_module_exit(void)
66{
67 nft_unregister_expr(&nft_reject_ipv4_type);
68}
69
70module_init(nft_reject_ipv4_module_init);
71module_exit(nft_reject_ipv4_module_exit);
72
73MODULE_LICENSE("GPL");
74MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
75MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "reject");
76MODULE_DESCRIPTION("IPv4 packet rejection for nftables");
77

source code of linux/net/ipv4/netfilter/nft_reject_ipv4.c