[mirror_ubuntu-bionic-kernel.git] / net / netfilter / nft_reject_inet.c

/*
 * Copyright (c) 2014 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nft_reject.h>
#include <net/netfilter/ipv4/nf_reject.h>
#include <net/netfilter/ipv6/nf_reject.h>

static void nft_reject_inet_eval(const struct nft_expr *expr,
				 struct nft_regs *regs,
				 const struct nft_pktinfo *pkt)
{
	struct nft_reject *priv = nft_expr_priv(expr);

	switch (nft_pf(pkt)) {
	case NFPROTO_IPV4:
		switch (priv->type) {
		case NFT_REJECT_ICMP_UNREACH:
			nf_send_unreach(pkt->skb, priv->icmp_code,
					nft_hook(pkt));
			break;
		case NFT_REJECT_TCP_RST:
			nf_send_reset(nft_net(pkt), pkt->skb, nft_hook(pkt));
			break;
		case NFT_REJECT_ICMPX_UNREACH:
			nf_send_unreach(pkt->skb,
					nft_reject_icmp_code(priv->icmp_code),
					nft_hook(pkt));
			break;
		}
		break;
	case NFPROTO_IPV6:
		switch (priv->type) {
		case NFT_REJECT_ICMP_UNREACH:
			nf_send_unreach6(nft_net(pkt), pkt->skb,
					 priv->icmp_code, nft_hook(pkt));
			break;
		case NFT_REJECT_TCP_RST:
			nf_send_reset6(nft_net(pkt), pkt->skb, nft_hook(pkt));
			break;
		case NFT_REJECT_ICMPX_UNREACH:
			nf_send_unreach6(nft_net(pkt), pkt->skb,
					 nft_reject_icmpv6_code(priv->icmp_code),
					 nft_hook(pkt));
			break;
		}
		break;
	}

	regs->verdict.code = NF_DROP;
}

static int nft_reject_inet_init(const struct nft_ctx *ctx,
				const struct nft_expr *expr,
				const struct nlattr * const tb[])
{
	struct nft_reject *priv = nft_expr_priv(expr);
	int icmp_code;

	if (tb[NFTA_REJECT_TYPE] == NULL)
		return -EINVAL;

	priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
	switch (priv->type) {
	case NFT_REJECT_ICMP_UNREACH:
	case NFT_REJECT_ICMPX_UNREACH:
		if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
			return -EINVAL;

		icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
		if (priv->type == NFT_REJECT_ICMPX_UNREACH &&
		    icmp_code > NFT_REJECT_ICMPX_MAX)
			return -EINVAL;

		priv->icmp_code = icmp_code;
		break;
	case NFT_REJECT_TCP_RST:
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static int nft_reject_inet_dump(struct sk_buff *skb,
				const struct nft_expr *expr)
{
	const struct nft_reject *priv = nft_expr_priv(expr);

	if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
		goto nla_put_failure;

	switch (priv->type) {
	case NFT_REJECT_ICMP_UNREACH:
	case NFT_REJECT_ICMPX_UNREACH:
		if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
			goto nla_put_failure;
		break;
	default:
		break;
	}

	return 0;

nla_put_failure:
	return -1;
}

static struct nft_expr_type nft_reject_inet_type;
static const struct nft_expr_ops nft_reject_inet_ops = {
	.type		= &nft_reject_inet_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_reject)),
	.eval		= nft_reject_inet_eval,
	.init		= nft_reject_inet_init,
	.dump		= nft_reject_inet_dump,
	.validate	= nft_reject_validate,
};

static struct nft_expr_type nft_reject_inet_type __read_mostly = {
	.family		= NFPROTO_INET,
	.name		= "reject",
	.ops		= &nft_reject_inet_ops,
	.policy		= nft_reject_policy,
	.maxattr	= NFTA_REJECT_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_reject_inet_module_init(void)
{
	return nft_register_expr(&nft_reject_inet_type);
}

static void __exit nft_reject_inet_module_exit(void)
{
	nft_unregister_expr(&nft_reject_inet_type);
}

module_init(nft_reject_inet_module_init);
module_exit(nft_reject_inet_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_AF_EXPR(1, "reject");
Commit	Line	Data
05513e9e PM	1	/*
	2	* Copyright (c) 2014 Patrick McHardy <kaber@trash.net>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	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>
51b0a5d8 PNA	17	#include <net/netfilter/ipv4/nf_reject.h>
51b0a5d8 PNA	18	#include <net/netfilter/ipv6/nf_reject.h>
05513e9e PM	19
05513e9e PM	20	static void nft_reject_inet_eval(const struct nft_expr *expr,
a55e22e9	21	struct nft_regs *regs,
05513e9e PM	22	const struct nft_pktinfo *pkt)
05513e9e PM	23	{
51b0a5d8	24	struct nft_reject *priv = nft_expr_priv(expr);
51b0a5d8	25
0e5a1c7e	26	switch (nft_pf(pkt)) {
05513e9e	27	case NFPROTO_IPV4:
51b0a5d8 PNA	28	switch (priv->type) {
51b0a5d8 PNA	29	case NFT_REJECT_ICMP_UNREACH:
ee586bbc	30	nf_send_unreach(pkt->skb, priv->icmp_code,
0e5a1c7e	31	nft_hook(pkt));
51b0a5d8 PNA	32	break;
51b0a5d8 PNA	33	case NFT_REJECT_TCP_RST:
0e5a1c7e	34	nf_send_reset(nft_net(pkt), pkt->skb, nft_hook(pkt));
51b0a5d8 PNA	35	break;
	36	case NFT_REJECT_ICMPX_UNREACH:
	37	nf_send_unreach(pkt->skb,
ee586bbc	38	nft_reject_icmp_code(priv->icmp_code),
0e5a1c7e	39	nft_hook(pkt));
51b0a5d8 PNA	40	break;
	41	}
	42	break;
05513e9e	43	case NFPROTO_IPV6:
51b0a5d8 PNA	44	switch (priv->type) {
51b0a5d8 PNA	45	case NFT_REJECT_ICMP_UNREACH:
0e5a1c7e PNA	46	nf_send_unreach6(nft_net(pkt), pkt->skb,
0e5a1c7e PNA	47	priv->icmp_code, nft_hook(pkt));
51b0a5d8 PNA	48	break;
51b0a5d8 PNA	49	case NFT_REJECT_TCP_RST:
0e5a1c7e	50	nf_send_reset6(nft_net(pkt), pkt->skb, nft_hook(pkt));
51b0a5d8 PNA	51	break;
51b0a5d8 PNA	52	case NFT_REJECT_ICMPX_UNREACH:
0e5a1c7e	53	nf_send_unreach6(nft_net(pkt), pkt->skb,
51b0a5d8	54	nft_reject_icmpv6_code(priv->icmp_code),
0e5a1c7e	55	nft_hook(pkt));
51b0a5d8 PNA	56	break;
	57	}
	58	break;
	59	}
a55e22e9 PM	60
a55e22e9 PM	61	regs->verdict.code = NF_DROP;
51b0a5d8 PNA	62	}
	63
	64	static int nft_reject_inet_init(const struct nft_ctx *ctx,
	65	const struct nft_expr *expr,
	66	const struct nlattr * const tb[])
	67	{
	68	struct nft_reject *priv = nft_expr_priv(expr);
c56e3956	69	int icmp_code;
51b0a5d8 PNA	70
	71	if (tb[NFTA_REJECT_TYPE] == NULL)
	72	return -EINVAL;
	73
	74	priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
	75	switch (priv->type) {
	76	case NFT_REJECT_ICMP_UNREACH:
	77	case NFT_REJECT_ICMPX_UNREACH:
	78	if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
	79	return -EINVAL;
	80
	81	icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
	82	if (priv->type == NFT_REJECT_ICMPX_UNREACH &&
	83	icmp_code > NFT_REJECT_ICMPX_MAX)
	84	return -EINVAL;
	85
	86	priv->icmp_code = icmp_code;
	87	break;
	88	case NFT_REJECT_TCP_RST:
	89	break;
	90	default:
	91	return -EINVAL;
05513e9e	92	}
51b0a5d8 PNA	93	return 0;
	94	}
	95
	96	static int nft_reject_inet_dump(struct sk_buff *skb,
	97	const struct nft_expr *expr)
	98	{
	99	const struct nft_reject *priv = nft_expr_priv(expr);
	100
	101	if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
	102	goto nla_put_failure;
	103
	104	switch (priv->type) {
	105	case NFT_REJECT_ICMP_UNREACH:
	106	case NFT_REJECT_ICMPX_UNREACH:
	107	if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
	108	goto nla_put_failure;
	109	break;
129d23a5 DM	110	default:
129d23a5 DM	111	break;
51b0a5d8 PNA	112	}
	113
	114	return 0;
	115
	116	nla_put_failure:
	117	return -1;
05513e9e PM	118	}
	119
	120	static struct nft_expr_type nft_reject_inet_type;
	121	static const struct nft_expr_ops nft_reject_inet_ops = {
	122	.type = &nft_reject_inet_type,
	123	.size = NFT_EXPR_SIZE(sizeof(struct nft_reject)),
	124	.eval = nft_reject_inet_eval,
51b0a5d8 PNA	125	.init = nft_reject_inet_init,
51b0a5d8 PNA	126	.dump = nft_reject_inet_dump,
89e1f6d2	127	.validate = nft_reject_validate,
05513e9e PM	128	};
	129
	130	static struct nft_expr_type nft_reject_inet_type __read_mostly = {
	131	.family = NFPROTO_INET,
	132	.name = "reject",
	133	.ops = &nft_reject_inet_ops,
	134	.policy = nft_reject_policy,
	135	.maxattr = NFTA_REJECT_MAX,
	136	.owner = THIS_MODULE,
	137	};
	138
	139	static int __init nft_reject_inet_module_init(void)
	140	{
	141	return nft_register_expr(&nft_reject_inet_type);
	142	}
	143
	144	static void __exit nft_reject_inet_module_exit(void)
	145	{
	146	nft_unregister_expr(&nft_reject_inet_type);
	147	}
	148
	149	module_init(nft_reject_inet_module_init);
	150	module_exit(nft_reject_inet_module_exit);
	151
	152	MODULE_LICENSE("GPL");
	153	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
	154	MODULE_ALIAS_NFT_AF_EXPR(1, "reject");