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
nft_reject_ipv4_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)19 static 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(pkt->skb, priv->icmp_code, nft_hook(pkt));
28 break;
29 case NFT_REJECT_TCP_RST:
30 nf_send_reset(nft_net(pkt), nft_sk(pkt), pkt->skb,
31 nft_hook(pkt));
32 break;
33 default:
34 break;
35 }
36
37 regs->verdict.code = NF_DROP;
38 }
39
40 static struct nft_expr_type nft_reject_ipv4_type;
41 static 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
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
nft_reject_ipv4_module_init(void)60 static int __init nft_reject_ipv4_module_init(void)
61 {
62 return nft_register_expr(&nft_reject_ipv4_type);
63 }
64
nft_reject_ipv4_module_exit(void)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");
76 MODULE_DESCRIPTION("IPv4 packet rejection for nftables");
77