[deliverable/linux.git] / net / bridge / netfilter / nft_reject_bridge.c

/*
 * Copyright (c) 2014 Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * 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>
#include <linux/ip.h>
#include <net/ip.h>
#include "../br_private.h"

static void nft_reject_br_push_etherhdr(struct sk_buff *oldskb,
					struct sk_buff *nskb)
{
	struct ethhdr *eth;

	eth = (struct ethhdr *)skb_push(nskb, ETH_HLEN);
	skb_reset_mac_header(nskb);
	ether_addr_copy(eth->h_source, eth_hdr(oldskb)->h_dest);
	ether_addr_copy(eth->h_dest, eth_hdr(oldskb)->h_source);
	eth->h_proto = eth_hdr(oldskb)->h_proto;
	skb_pull(nskb, ETH_HLEN);
}

static int nft_reject_iphdr_validate(struct sk_buff *oldskb)
{
	struct iphdr *iph;
	u32 len;

	if (!pskb_may_pull(oldskb, sizeof(struct iphdr)))
		return 0;

	iph = ip_hdr(oldskb);
	if (iph->ihl < 5 || iph->version != 4)
		return 0;

	len = ntohs(iph->tot_len);
	if (oldskb->len < len)
		return 0;
	else if (len < (iph->ihl*4))
		return 0;

	if (!pskb_may_pull(oldskb, iph->ihl*4))
		return 0;

	return 1;
}

static void nft_reject_br_send_v4_tcp_reset(struct sk_buff *oldskb, int hook)
{
	struct sk_buff *nskb;
	struct iphdr *niph;
	const struct tcphdr *oth;
	struct tcphdr _oth;

	if (!nft_reject_iphdr_validate(oldskb))
		return;

	oth = nf_reject_ip_tcphdr_get(oldskb, &_oth, hook);
	if (!oth)
		return;

	nskb = alloc_skb(sizeof(struct iphdr) + sizeof(struct tcphdr) +
			 LL_MAX_HEADER, GFP_ATOMIC);
	if (!nskb)
		return;

	skb_reserve(nskb, LL_MAX_HEADER);
	niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_TCP,
				   sysctl_ip_default_ttl);
	nf_reject_ip_tcphdr_put(nskb, oldskb, oth);
	niph->ttl	= sysctl_ip_default_ttl;
	niph->tot_len	= htons(nskb->len);
	ip_send_check(niph);

	nft_reject_br_push_etherhdr(oldskb, nskb);

	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
}

static void nft_reject_br_send_v4_unreach(struct sk_buff *oldskb, int hook,
					  u8 code)
{
	struct sk_buff *nskb;
	struct iphdr *niph;
	struct icmphdr *icmph;
	unsigned int len;
	void *payload;
	__wsum csum;

	if (!nft_reject_iphdr_validate(oldskb))
		return;

	/* IP header checks: fragment. */
	if (ip_hdr(oldskb)->frag_off & htons(IP_OFFSET))
		return;

	/* RFC says return as much as we can without exceeding 576 bytes. */
	len = min_t(unsigned int, 536, oldskb->len);

	if (!pskb_may_pull(oldskb, len))
		return;

	if (nf_ip_checksum(oldskb, hook, ip_hdrlen(oldskb), 0))
		return;

	nskb = alloc_skb(sizeof(struct iphdr) + sizeof(struct icmphdr) +
			 LL_MAX_HEADER + len, GFP_ATOMIC);
	if (!nskb)
		return;

	skb_reserve(nskb, LL_MAX_HEADER);
	niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_ICMP,
				   sysctl_ip_default_ttl);

	skb_reset_transport_header(nskb);
	icmph = (struct icmphdr *)skb_put(nskb, sizeof(struct icmphdr));
	memset(icmph, 0, sizeof(*icmph));
	icmph->type     = ICMP_DEST_UNREACH;
	icmph->code	= code;

	payload = skb_put(nskb, len);
	memcpy(payload, skb_network_header(oldskb), len);

	csum = csum_partial((void *)icmph, len + sizeof(struct icmphdr), 0);
	icmph->checksum = csum_fold(csum);

	niph->tot_len	= htons(nskb->len);
	ip_send_check(niph);

	nft_reject_br_push_etherhdr(oldskb, nskb);

	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
}

static int nft_reject_ip6hdr_validate(struct sk_buff *oldskb)
{
	struct ipv6hdr *hdr;
	u32 pkt_len;

	if (!pskb_may_pull(oldskb, sizeof(struct ipv6hdr)))
		return 0;

	hdr = ipv6_hdr(oldskb);
	if (hdr->version != 6)
		return 0;

	pkt_len = ntohs(hdr->payload_len);
	if (pkt_len + sizeof(struct ipv6hdr) > oldskb->len)
		return 0;

	return 1;
}

static void nft_reject_br_send_v6_tcp_reset(struct net *net,
					    struct sk_buff *oldskb, int hook)
{
	struct sk_buff *nskb;
	const struct tcphdr *oth;
	struct tcphdr _oth;
	unsigned int otcplen;
	struct ipv6hdr *nip6h;

	if (!nft_reject_ip6hdr_validate(oldskb))
		return;

	oth = nf_reject_ip6_tcphdr_get(oldskb, &_oth, &otcplen, hook);
	if (!oth)
		return;

	nskb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(struct tcphdr) +
			 LL_MAX_HEADER, GFP_ATOMIC);
	if (!nskb)
		return;

	skb_reserve(nskb, LL_MAX_HEADER);
	nip6h = nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_TCP,
				     net->ipv6.devconf_all->hop_limit);
	nf_reject_ip6_tcphdr_put(nskb, oldskb, oth, otcplen);
	nip6h->payload_len = htons(nskb->len - sizeof(struct ipv6hdr));

	nft_reject_br_push_etherhdr(oldskb, nskb);

	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
}

static void nft_reject_br_send_v6_unreach(struct net *net,
					  struct sk_buff *oldskb, int hook,
					  u8 code)
{
	struct sk_buff *nskb;
	struct ipv6hdr *nip6h;
	struct icmp6hdr *icmp6h;
	unsigned int len;
	void *payload;

	if (!nft_reject_ip6hdr_validate(oldskb))
		return;

	/* Include "As much of invoking packet as possible without the ICMPv6
	 * packet exceeding the minimum IPv6 MTU" in the ICMP payload.
	 */
	len = min_t(unsigned int, 1220, oldskb->len);

	if (!pskb_may_pull(oldskb, len))
		return;

	nskb = alloc_skb(sizeof(struct iphdr) + sizeof(struct icmp6hdr) +
			 LL_MAX_HEADER + len, GFP_ATOMIC);
	if (!nskb)
		return;

	skb_reserve(nskb, LL_MAX_HEADER);
	nip6h = nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_ICMPV6,
				     net->ipv6.devconf_all->hop_limit);

	skb_reset_transport_header(nskb);
	icmp6h = (struct icmp6hdr *)skb_put(nskb, sizeof(struct icmp6hdr));
	memset(icmp6h, 0, sizeof(*icmp6h));
	icmp6h->icmp6_type = ICMPV6_DEST_UNREACH;
	icmp6h->icmp6_code = code;

	payload = skb_put(nskb, len);
	memcpy(payload, skb_network_header(oldskb), len);
	nip6h->payload_len = htons(nskb->len - sizeof(struct ipv6hdr));

	icmp6h->icmp6_cksum =
		csum_ipv6_magic(&nip6h->saddr, &nip6h->daddr,
				nskb->len - sizeof(struct ipv6hdr),
				IPPROTO_ICMPV6,
				csum_partial(icmp6h,
					     nskb->len - sizeof(struct ipv6hdr),
					     0));

	nft_reject_br_push_etherhdr(oldskb, nskb);

	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
}

static void nft_reject_bridge_eval(const struct nft_expr *expr,
				 struct nft_data data[NFT_REG_MAX + 1],
				 const struct nft_pktinfo *pkt)
{
	struct nft_reject *priv = nft_expr_priv(expr);
	struct net *net = dev_net((pkt->in != NULL) ? pkt->in : pkt->out);
	const unsigned char *dest = eth_hdr(pkt->skb)->h_dest;

	if (is_broadcast_ether_addr(dest) ||
	    is_multicast_ether_addr(dest))
		goto out;

	switch (eth_hdr(pkt->skb)->h_proto) {
	case htons(ETH_P_IP):
		switch (priv->type) {
		case NFT_REJECT_ICMP_UNREACH:
			nft_reject_br_send_v4_unreach(pkt->skb,
						      pkt->ops->hooknum,
						      priv->icmp_code);
			break;
		case NFT_REJECT_TCP_RST:
			nft_reject_br_send_v4_tcp_reset(pkt->skb,
							pkt->ops->hooknum);
			break;
		case NFT_REJECT_ICMPX_UNREACH:
			nft_reject_br_send_v4_unreach(pkt->skb,
						      pkt->ops->hooknum,
						      nft_reject_icmp_code(priv->icmp_code));
			break;
		}
		break;
	case htons(ETH_P_IPV6):
		switch (priv->type) {
		case NFT_REJECT_ICMP_UNREACH:
			nft_reject_br_send_v6_unreach(net, pkt->skb,
						      pkt->ops->hooknum,
						      priv->icmp_code);
			break;
		case NFT_REJECT_TCP_RST:
			nft_reject_br_send_v6_tcp_reset(net, pkt->skb,
							pkt->ops->hooknum);
			break;
		case NFT_REJECT_ICMPX_UNREACH:
			nft_reject_br_send_v6_unreach(net, pkt->skb,
						      pkt->ops->hooknum,
						      nft_reject_icmpv6_code(priv->icmp_code));
			break;
		}
		break;
	default:
		/* No explicit way to reject this protocol, drop it. */
		break;
	}
out:
	data[NFT_REG_VERDICT].verdict = NF_DROP;
}

static int nft_reject_bridge_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_bridge_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;
	}

	return 0;

nla_put_failure:
	return -1;
}

static struct nft_expr_type nft_reject_bridge_type;
static const struct nft_expr_ops nft_reject_bridge_ops = {
	.type		= &nft_reject_bridge_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_reject)),
	.eval		= nft_reject_bridge_eval,
	.init		= nft_reject_bridge_init,
	.dump		= nft_reject_bridge_dump,
};

static struct nft_expr_type nft_reject_bridge_type __read_mostly = {
	.family		= NFPROTO_BRIDGE,
	.name		= "reject",
	.ops		= &nft_reject_bridge_ops,
	.policy		= nft_reject_policy,
	.maxattr	= NFTA_REJECT_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_reject_bridge_module_init(void)
{
	return nft_register_expr(&nft_reject_bridge_type);
}

static void __exit nft_reject_bridge_module_exit(void)
{
	nft_unregister_expr(&nft_reject_bridge_type);
}

module_init(nft_reject_bridge_module_init);
module_exit(nft_reject_bridge_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "reject");
Commit	Line	Data
85f5b308 PNA	1	/*
	2	* Copyright (c) 2014 Pablo Neira Ayuso <pablo@netfilter.org>
	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>
523b929d PNA	19	#include <linux/ip.h>
	20	#include <net/ip.h>
	21	#include "../br_private.h"
	22
	23	static void nft_reject_br_push_etherhdr(struct sk_buff *oldskb,
	24	struct sk_buff *nskb)
	25	{
	26	struct ethhdr *eth;
	27
	28	eth = (struct ethhdr *)skb_push(nskb, ETH_HLEN);
	29	skb_reset_mac_header(nskb);
	30	ether_addr_copy(eth->h_source, eth_hdr(oldskb)->h_dest);
	31	ether_addr_copy(eth->h_dest, eth_hdr(oldskb)->h_source);
	32	eth->h_proto = eth_hdr(oldskb)->h_proto;
	33	skb_pull(nskb, ETH_HLEN);
	34	}
	35
	36	static int nft_reject_iphdr_validate(struct sk_buff *oldskb)
	37	{
	38	struct iphdr *iph;
	39	u32 len;
	40
	41	if (!pskb_may_pull(oldskb, sizeof(struct iphdr)))
	42	return 0;
	43
	44	iph = ip_hdr(oldskb);
	45	if (iph->ihl < 5 \|\| iph->version != 4)
	46	return 0;
	47
	48	len = ntohs(iph->tot_len);
	49	if (oldskb->len < len)
	50	return 0;
	51	else if (len < (iph->ihl*4))
	52	return 0;
	53
	54	if (!pskb_may_pull(oldskb, iph->ihl*4))
	55	return 0;
	56
	57	return 1;
	58	}
	59
	60	static void nft_reject_br_send_v4_tcp_reset(struct sk_buff *oldskb, int hook)
	61	{
	62	struct sk_buff *nskb;
	63	struct iphdr *niph;
	64	const struct tcphdr *oth;
	65	struct tcphdr _oth;
	66
	67	if (!nft_reject_iphdr_validate(oldskb))
	68	return;
	69
	70	oth = nf_reject_ip_tcphdr_get(oldskb, &_oth, hook);
	71	if (!oth)
	72	return;
	73
	74	nskb = alloc_skb(sizeof(struct iphdr) + sizeof(struct tcphdr) +
	75	LL_MAX_HEADER, GFP_ATOMIC);
	76	if (!nskb)
	77	return;
	78
	79	skb_reserve(nskb, LL_MAX_HEADER);
	80	niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_TCP,
	81	sysctl_ip_default_ttl);
	82	nf_reject_ip_tcphdr_put(nskb, oldskb, oth);
83	niph->ttl = sysctl_ip_default_ttl;
84	niph->tot_len = htons(nskb->len);
85	ip_send_check(niph);
86
87	nft_reject_br_push_etherhdr(oldskb, nskb);
88
89	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
90	}
91
92	static void nft_reject_br_send_v4_unreach(struct sk_buff *oldskb, int hook,
93	u8 code)
94	{
95	struct sk_buff *nskb;
96	struct iphdr *niph;
97	struct icmphdr *icmph;
98	unsigned int len;
99	void *payload;
100	__wsum csum;
101
102	if (!nft_reject_iphdr_validate(oldskb))
103	return;
104
105	/* IP header checks: fragment. */
106	if (ip_hdr(oldskb)->frag_off & htons(IP_OFFSET))
107	return;
108
109	/* RFC says return as much as we can without exceeding 576 bytes. */
110	len = min_t(unsigned int, 536, oldskb->len);
111
112	if (!pskb_may_pull(oldskb, len))
113	return;
114
115	if (nf_ip_checksum(oldskb, hook, ip_hdrlen(oldskb), 0))
116	return;
117
118	nskb = alloc_skb(sizeof(struct iphdr) + sizeof(struct icmphdr) +
119	LL_MAX_HEADER + len, GFP_ATOMIC);
120	if (!nskb)
121	return;
122
123	skb_reserve(nskb, LL_MAX_HEADER);
124	niph = nf_reject_iphdr_put(nskb, oldskb, IPPROTO_ICMP,
125	sysctl_ip_default_ttl);
126
127	skb_reset_transport_header(nskb);
128	icmph = (struct icmphdr *)skb_put(nskb, sizeof(struct icmphdr));
129	memset(icmph, 0, sizeof(*icmph));
130	icmph->type = ICMP_DEST_UNREACH;
131	icmph->code = code;
132
133	payload = skb_put(nskb, len);
134	memcpy(payload, skb_network_header(oldskb), len);
135
136	csum = csum_partial((void *)icmph, len + sizeof(struct icmphdr), 0);
137	icmph->checksum = csum_fold(csum);
138
139	niph->tot_len = htons(nskb->len);
140	ip_send_check(niph);
141
142	nft_reject_br_push_etherhdr(oldskb, nskb);
143
144	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
145	}
146
147	static int nft_reject_ip6hdr_validate(struct sk_buff *oldskb)
148	{
149	struct ipv6hdr *hdr;
150	u32 pkt_len;
151
152	if (!pskb_may_pull(oldskb, sizeof(struct ipv6hdr)))
153	return 0;
154
155	hdr = ipv6_hdr(oldskb);
156	if (hdr->version != 6)
157	return 0;
158
159	pkt_len = ntohs(hdr->payload_len);
160	if (pkt_len + sizeof(struct ipv6hdr) > oldskb->len)
161	return 0;
162
163	return 1;
164	}
165
166	static void nft_reject_br_send_v6_tcp_reset(struct net *net,
167	struct sk_buff *oldskb, int hook)
168	{
169	struct sk_buff *nskb;
170	const struct tcphdr *oth;
171	struct tcphdr _oth;
172	unsigned int otcplen;
173	struct ipv6hdr *nip6h;
174
175	if (!nft_reject_ip6hdr_validate(oldskb))
176	return;
177
178	oth = nf_reject_ip6_tcphdr_get(oldskb, &_oth, &otcplen, hook);
179	if (!oth)
180	return;
181
182	nskb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(struct tcphdr) +
183	LL_MAX_HEADER, GFP_ATOMIC);
184	if (!nskb)
185	return;
186
187	skb_reserve(nskb, LL_MAX_HEADER);
188	nip6h = nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_TCP,
189	net->ipv6.devconf_all->hop_limit);
190	nf_reject_ip6_tcphdr_put(nskb, oldskb, oth, otcplen);
191	nip6h->payload_len = htons(nskb->len - sizeof(struct ipv6hdr));
192
193	nft_reject_br_push_etherhdr(oldskb, nskb);
194
195	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
196	}
197
198	static void nft_reject_br_send_v6_unreach(struct net *net,
199	struct sk_buff *oldskb, int hook,
200	u8 code)
201	{
202	struct sk_buff *nskb;
203	struct ipv6hdr *nip6h;
204	struct icmp6hdr *icmp6h;
205	unsigned int len;
206	void *payload;
207
208	if (!nft_reject_ip6hdr_validate(oldskb))
209	return;
210
211	/* Include "As much of invoking packet as possible without the ICMPv6
212	* packet exceeding the minimum IPv6 MTU" in the ICMP payload.
213	*/
214	len = min_t(unsigned int, 1220, oldskb->len);
215
216	if (!pskb_may_pull(oldskb, len))
217	return;
218
219	nskb = alloc_skb(sizeof(struct iphdr) + sizeof(struct icmp6hdr) +
220	LL_MAX_HEADER + len, GFP_ATOMIC);
221	if (!nskb)
222	return;
223
224	skb_reserve(nskb, LL_MAX_HEADER);
225	nip6h = nf_reject_ip6hdr_put(nskb, oldskb, IPPROTO_ICMPV6,
226	net->ipv6.devconf_all->hop_limit);
227
228	skb_reset_transport_header(nskb);
229	icmp6h = (struct icmp6hdr *)skb_put(nskb, sizeof(struct icmp6hdr));
230	memset(icmp6h, 0, sizeof(*icmp6h));
231	icmp6h->icmp6_type = ICMPV6_DEST_UNREACH;
232	icmp6h->icmp6_code = code;
233
234	payload = skb_put(nskb, len);
235	memcpy(payload, skb_network_header(oldskb), len);
236	nip6h->payload_len = htons(nskb->len - sizeof(struct ipv6hdr));
237
238	icmp6h->icmp6_cksum =
239	csum_ipv6_magic(&nip6h->saddr, &nip6h->daddr,
240	nskb->len - sizeof(struct ipv6hdr),
241	IPPROTO_ICMPV6,
242	csum_partial(icmp6h,
243	nskb->len - sizeof(struct ipv6hdr),
244	0));
245
246	nft_reject_br_push_etherhdr(oldskb, nskb);
247
248	br_deliver(br_port_get_rcu(oldskb->dev), nskb);
249	}
85f5b308 PNA	250
	251	static void nft_reject_bridge_eval(const struct nft_expr *expr,
	252	struct nft_data data[NFT_REG_MAX + 1],
	253	const struct nft_pktinfo *pkt)
	254	{
51b0a5d8 PNA	255	struct nft_reject *priv = nft_expr_priv(expr);
51b0a5d8 PNA	256	struct net *net = dev_net((pkt->in != NULL) ? pkt->in : pkt->out);
523b929d PNA	257	const unsigned char *dest = eth_hdr(pkt->skb)->h_dest;
	258
	259	if (is_broadcast_ether_addr(dest) \|\|
	260	is_multicast_ether_addr(dest))
	261	goto out;
51b0a5d8	262
85f5b308 PNA	263	switch (eth_hdr(pkt->skb)->h_proto) {
85f5b308 PNA	264	case htons(ETH_P_IP):
51b0a5d8 PNA	265	switch (priv->type) {
51b0a5d8 PNA	266	case NFT_REJECT_ICMP_UNREACH:
523b929d PNA	267	nft_reject_br_send_v4_unreach(pkt->skb,
	268	pkt->ops->hooknum,
	269	priv->icmp_code);
51b0a5d8 PNA	270	break;
51b0a5d8 PNA	271	case NFT_REJECT_TCP_RST:
523b929d PNA	272	nft_reject_br_send_v4_tcp_reset(pkt->skb,
523b929d PNA	273	pkt->ops->hooknum);
51b0a5d8 PNA	274	break;
51b0a5d8 PNA	275	case NFT_REJECT_ICMPX_UNREACH:
523b929d PNA	276	nft_reject_br_send_v4_unreach(pkt->skb,
	277	pkt->ops->hooknum,
	278	nft_reject_icmp_code(priv->icmp_code));
51b0a5d8 PNA	279	break;
	280	}
	281	break;
85f5b308	282	case htons(ETH_P_IPV6):
51b0a5d8 PNA	283	switch (priv->type) {
51b0a5d8 PNA	284	case NFT_REJECT_ICMP_UNREACH:
523b929d PNA	285	nft_reject_br_send_v6_unreach(net, pkt->skb,
	286	pkt->ops->hooknum,
	287	priv->icmp_code);
51b0a5d8 PNA	288	break;
51b0a5d8 PNA	289	case NFT_REJECT_TCP_RST:
523b929d PNA	290	nft_reject_br_send_v6_tcp_reset(net, pkt->skb,
523b929d PNA	291	pkt->ops->hooknum);
51b0a5d8 PNA	292	break;
51b0a5d8 PNA	293	case NFT_REJECT_ICMPX_UNREACH:
523b929d PNA	294	nft_reject_br_send_v6_unreach(net, pkt->skb,
	295	pkt->ops->hooknum,
	296	nft_reject_icmpv6_code(priv->icmp_code));
51b0a5d8 PNA	297	break;
	298	}
	299	break;
85f5b308 PNA	300	default:
85f5b308 PNA	301	/* No explicit way to reject this protocol, drop it. */
85f5b308 PNA	302	break;
85f5b308 PNA	303	}
523b929d	304	out:
51b0a5d8 PNA	305	data[NFT_REG_VERDICT].verdict = NF_DROP;
	306	}
	307
	308	static int nft_reject_bridge_init(const struct nft_ctx *ctx,
	309	const struct nft_expr *expr,
	310	const struct nlattr * const tb[])
	311	{
	312	struct nft_reject *priv = nft_expr_priv(expr);
	313	int icmp_code;
	314
	315	if (tb[NFTA_REJECT_TYPE] == NULL)
	316	return -EINVAL;
	317
	318	priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE]));
	319	switch (priv->type) {
	320	case NFT_REJECT_ICMP_UNREACH:
	321	case NFT_REJECT_ICMPX_UNREACH:
	322	if (tb[NFTA_REJECT_ICMP_CODE] == NULL)
	323	return -EINVAL;
	324
	325	icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
	326	if (priv->type == NFT_REJECT_ICMPX_UNREACH &&
	327	icmp_code > NFT_REJECT_ICMPX_MAX)
	328	return -EINVAL;
	329
	330	priv->icmp_code = icmp_code;
	331	break;
	332	case NFT_REJECT_TCP_RST:
	333	break;
	334	default:
	335	return -EINVAL;
	336	}
	337	return 0;
	338	}
	339
	340	static int nft_reject_bridge_dump(struct sk_buff *skb,
	341	const struct nft_expr *expr)
	342	{
	343	const struct nft_reject *priv = nft_expr_priv(expr);
	344
	345	if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type)))
	346	goto nla_put_failure;
	347
	348	switch (priv->type) {
	349	case NFT_REJECT_ICMP_UNREACH:
	350	case NFT_REJECT_ICMPX_UNREACH:
	351	if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code))
	352	goto nla_put_failure;
	353	break;
	354	}
	355
	356	return 0;
	357
	358	nla_put_failure:
	359	return -1;
85f5b308 PNA	360	}
	361
	362	static struct nft_expr_type nft_reject_bridge_type;
	363	static const struct nft_expr_ops nft_reject_bridge_ops = {
	364	.type = &nft_reject_bridge_type,
	365	.size = NFT_EXPR_SIZE(sizeof(struct nft_reject)),
	366	.eval = nft_reject_bridge_eval,
51b0a5d8 PNA	367	.init = nft_reject_bridge_init,
51b0a5d8 PNA	368	.dump = nft_reject_bridge_dump,
85f5b308 PNA	369	};
	370
	371	static struct nft_expr_type nft_reject_bridge_type __read_mostly = {
	372	.family = NFPROTO_BRIDGE,
	373	.name = "reject",
	374	.ops = &nft_reject_bridge_ops,
	375	.policy = nft_reject_policy,
	376	.maxattr = NFTA_REJECT_MAX,
	377	.owner = THIS_MODULE,
	378	};
	379
	380	static int __init nft_reject_bridge_module_init(void)
	381	{
	382	return nft_register_expr(&nft_reject_bridge_type);
	383	}
	384
	385	static void __exit nft_reject_bridge_module_exit(void)
	386	{
	387	nft_unregister_expr(&nft_reject_bridge_type);
	388	}
	389
	390	module_init(nft_reject_bridge_module_init);
	391	module_exit(nft_reject_bridge_module_exit);
	392
	393	MODULE_LICENSE("GPL");
	394	MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
	395	MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "reject");