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/nft_reject.h>
 17#include <linux/icmp.h>
 18#include <linux/icmpv6.h>
 19
 20const struct nla_policy nft_reject_policy[NFTA_REJECT_MAX + 1] = {
 21	[NFTA_REJECT_TYPE]		= { .type = NLA_U32 },
 22	[NFTA_REJECT_ICMP_CODE]		= { .type = NLA_U8 },
 23};
 24EXPORT_SYMBOL_GPL(nft_reject_policy);
 25
 26int nft_reject_validate(const struct nft_ctx *ctx,
 27			const struct nft_expr *expr,
 28			const struct nft_data **data)
 29{
 30	return nft_chain_validate_hooks(ctx->chain,
 31					(1 << NF_INET_LOCAL_IN) |
 32					(1 << NF_INET_FORWARD) |
 33					(1 << NF_INET_LOCAL_OUT) |
 34					(1 << NF_INET_PRE_ROUTING));
 35}
 36EXPORT_SYMBOL_GPL(nft_reject_validate);
 37
 38int nft_reject_init(const struct nft_ctx *ctx,
 39		    const struct nft_expr *expr,
 40		    const struct nlattr * const tb[])
 41{
 42	struct nft_reject *priv = nft_expr_priv(expr);
 43
 44	if (tb[NFTA_REJECT_TYPE] == NULL)
 45		return -EINVAL;
 46
 47	priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
 48	switch (priv->type) {
 49	case NFT_REJECT_ICMP_UNREACH:
 50		if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
 51			return -EINVAL;
 52		priv->icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
 53	case NFT_REJECT_TCP_RST:
 54		break;
 55	default:
 56		return -EINVAL;
 57	}
 58
 59	return 0;
 60}
 61EXPORT_SYMBOL_GPL(nft_reject_init);
 62
 63int nft_reject_dump(struct sk_buff *skb, const struct nft_expr *expr)
 64{
 65	const struct nft_reject *priv = nft_expr_priv(expr);
 66
 67	if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
 68		goto nla_put_failure;
 69
 70	switch (priv->type) {
 71	case NFT_REJECT_ICMP_UNREACH:
 72		if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
 73			goto nla_put_failure;
 74		break;
 75	default:
 76		break;
 77	}
 78
 79	return 0;
 80
 81nla_put_failure:
 82	return -1;
 83}
 84EXPORT_SYMBOL_GPL(nft_reject_dump);
 85
 86static u8 icmp_code_v4[NFT_REJECT_ICMPX_MAX + 1] = {
 87	[NFT_REJECT_ICMPX_NO_ROUTE]		= ICMP_NET_UNREACH,
 88	[NFT_REJECT_ICMPX_PORT_UNREACH]		= ICMP_PORT_UNREACH,
 89	[NFT_REJECT_ICMPX_HOST_UNREACH]		= ICMP_HOST_UNREACH,
 90	[NFT_REJECT_ICMPX_ADMIN_PROHIBITED]	= ICMP_PKT_FILTERED,
 91};
 92
 93int nft_reject_icmp_code(u8 code)
 94{
 95	if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX))
 96		return ICMP_NET_UNREACH;
 97
 98	return icmp_code_v4[code];
 99}
100
101EXPORT_SYMBOL_GPL(nft_reject_icmp_code);
102
103
104static u8 icmp_code_v6[NFT_REJECT_ICMPX_MAX + 1] = {
105	[NFT_REJECT_ICMPX_NO_ROUTE]		= ICMPV6_NOROUTE,
106	[NFT_REJECT_ICMPX_PORT_UNREACH]		= ICMPV6_PORT_UNREACH,
107	[NFT_REJECT_ICMPX_HOST_UNREACH]		= ICMPV6_ADDR_UNREACH,
108	[NFT_REJECT_ICMPX_ADMIN_PROHIBITED]	= ICMPV6_ADM_PROHIBITED,
109};
110
111int nft_reject_icmpv6_code(u8 code)
112{
113	if (WARN_ON_ONCE(code > NFT_REJECT_ICMPX_MAX))
114		return ICMPV6_NOROUTE;
115
116	return icmp_code_v6[code];
117}
118
119EXPORT_SYMBOL_GPL(nft_reject_icmpv6_code);
120
121MODULE_LICENSE("GPL");
122MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
123MODULE_DESCRIPTION("Netfilter x_tables over nftables module");