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 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 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"); 76 MODULE_DESCRIPTION("IPv4 packet rejection for nftables"); 77