[deliverable/linux.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 (pkt->pf) {
	case NFPROTO_IPV4:
		switch (priv->type) {
		case NFT_REJECT_ICMP_UNREACH:
			nf_send_unreach(pkt->skb, priv->icmp_code,
					pkt->hook);
			break;
		case NFT_REJECT_TCP_RST:
			nf_send_reset(pkt->net, pkt->skb, pkt->hook);
			break;
		case NFT_REJECT_ICMPX_UNREACH:
			nf_send_unreach(pkt->skb,
					nft_reject_icmp_code(priv->icmp_code),
					pkt->hook);
			break;
		}
		break;
	case NFPROTO_IPV6:
		switch (priv->type) {
		case NFT_REJECT_ICMP_UNREACH:
			nf_send_unreach6(pkt->net, pkt->skb, priv->icmp_code,
					 pkt->hook);
			break;
		case NFT_REJECT_TCP_RST:
			nf_send_reset6(pkt->net, pkt->skb, pkt->hook);
			break;
		case NFT_REJECT_ICMPX_UNREACH:
			nf_send_unreach6(pkt->net, pkt->skb,
					 nft_reject_icmpv6_code(priv->icmp_code),
					 pkt->hook);
			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, err;

	err = nft_reject_validate(ctx, expr, NULL);
	if (err < 0)
		return err;

	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
6aa187f2	26	switch (pkt->pf) {
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,
6aa187f2	31	pkt->hook);
51b0a5d8 PNA	32	break;
51b0a5d8 PNA	33	case NFT_REJECT_TCP_RST:
372892ec	34	nf_send_reset(pkt->net, pkt->skb, pkt->hook);
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),
6aa187f2	39	pkt->hook);
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:
88182a0e	46	nf_send_unreach6(pkt->net, pkt->skb, priv->icmp_code,
6aa187f2	47	pkt->hook);
51b0a5d8 PNA	48	break;
51b0a5d8 PNA	49	case NFT_REJECT_TCP_RST:
88182a0e	50	nf_send_reset6(pkt->net, pkt->skb, pkt->hook);
51b0a5d8 PNA	51	break;
51b0a5d8 PNA	52	case NFT_REJECT_ICMPX_UNREACH:
88182a0e	53	nf_send_unreach6(pkt->net, pkt->skb,
51b0a5d8	54	nft_reject_icmpv6_code(priv->icmp_code),
6aa187f2	55	pkt->hook);
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);
89e1f6d2 LZ	69	int icmp_code, err;
	70
	71	err = nft_reject_validate(ctx, expr, NULL);
	72	if (err < 0)
	73	return err;
51b0a5d8 PNA	74
	75	if (tb[NFTA_REJECT_TYPE] == NULL)
	76	return -EINVAL;
	77
	78	priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
	79	switch (priv->type) {
	80	case NFT_REJECT_ICMP_UNREACH:
	81	case NFT_REJECT_ICMPX_UNREACH:
	82	if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
	83	return -EINVAL;
	84
	85	icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
	86	if (priv->type == NFT_REJECT_ICMPX_UNREACH &&
	87	icmp_code > NFT_REJECT_ICMPX_MAX)
	88	return -EINVAL;
	89
	90	priv->icmp_code = icmp_code;
	91	break;
	92	case NFT_REJECT_TCP_RST:
	93	break;
	94	default:
	95	return -EINVAL;
05513e9e	96	}
51b0a5d8 PNA	97	return 0;
	98	}
	99
	100	static int nft_reject_inet_dump(struct sk_buff *skb,
	101	const struct nft_expr *expr)
	102	{
	103	const struct nft_reject *priv = nft_expr_priv(expr);
	104
	105	if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
	106	goto nla_put_failure;
	107
	108	switch (priv->type) {
	109	case NFT_REJECT_ICMP_UNREACH:
	110	case NFT_REJECT_ICMPX_UNREACH:
	111	if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
	112	goto nla_put_failure;
	113	break;
129d23a5 DM	114	default:
129d23a5 DM	115	break;
51b0a5d8 PNA	116	}
	117
	118	return 0;
	119
	120	nla_put_failure:
	121	return -1;
05513e9e PM	122	}
	123
	124	static struct nft_expr_type nft_reject_inet_type;
	125	static const struct nft_expr_ops nft_reject_inet_ops = {
	126	.type = &nft_reject_inet_type,
	127	.size = NFT_EXPR_SIZE(sizeof(struct nft_reject)),
	128	.eval = nft_reject_inet_eval,
51b0a5d8 PNA	129	.init = nft_reject_inet_init,
51b0a5d8 PNA	130	.dump = nft_reject_inet_dump,
89e1f6d2	131	.validate = nft_reject_validate,
05513e9e PM	132	};
	133
	134	static struct nft_expr_type nft_reject_inet_type __read_mostly = {
	135	.family = NFPROTO_INET,
	136	.name = "reject",
	137	.ops = &nft_reject_inet_ops,
	138	.policy = nft_reject_policy,
	139	.maxattr = NFTA_REJECT_MAX,
	140	.owner = THIS_MODULE,
	141	};
	142
	143	static int __init nft_reject_inet_module_init(void)
	144	{
	145	return nft_register_expr(&nft_reject_inet_type);
	146	}
	147
	148	static void __exit nft_reject_inet_module_exit(void)
	149	{
	150	nft_unregister_expr(&nft_reject_inet_type);
	151	}
	152
	153	module_init(nft_reject_inet_module_init);
	154	module_exit(nft_reject_inet_module_exit);
	155
	156	MODULE_LICENSE("GPL");
	157	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
	158	MODULE_ALIAS_NFT_AF_EXPR(1, "reject");