[mirror_ubuntu-artful-kernel.git] / net / bridge / br_input.c

/*
 *	Handle incoming frames
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/netfilter_bridge.h>
#include <linux/neighbour.h>
#include <net/arp.h>
#include <linux/export.h>
#include <linux/rculist.h>
#include "br_private.h"
#include "br_private_tunnel.h"

/* Hook for brouter */
br_should_route_hook_t __rcu *br_should_route_hook __read_mostly;
EXPORT_SYMBOL(br_should_route_hook);

static int
br_netif_receive_skb(struct net *net, struct sock *sk, struct sk_buff *skb)
{
	br_drop_fake_rtable(skb);
	return netif_receive_skb(skb);
}

static int br_pass_frame_up(struct sk_buff *skb)
{
	struct net_device *indev, *brdev = BR_INPUT_SKB_CB(skb)->brdev;
	struct net_bridge *br = netdev_priv(brdev);
	struct net_bridge_vlan_group *vg;
	struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);

	u64_stats_update_begin(&brstats->syncp);
	brstats->rx_packets++;
	brstats->rx_bytes += skb->len;
	u64_stats_update_end(&brstats->syncp);

	vg = br_vlan_group_rcu(br);
	/* Bridge is just like any other port.  Make sure the
	 * packet is allowed except in promisc modue when someone
	 * may be running packet capture.
	 */
	if (!(brdev->flags & IFF_PROMISC) &&
	    !br_allowed_egress(vg, skb)) {
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	indev = skb->dev;
	skb->dev = brdev;
	skb = br_handle_vlan(br, NULL, vg, skb);
	if (!skb)
		return NET_RX_DROP;
	/* update the multicast stats if the packet is IGMP/MLD */
	br_multicast_count(br, NULL, skb, br_multicast_igmp_type(skb),
			   BR_MCAST_DIR_TX);

	return NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN,
		       dev_net(indev), NULL, skb, indev, NULL,
		       br_netif_receive_skb);
}

static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br,
			    u16 vid, struct net_bridge_port *p)
{
	struct net_device *dev = br->dev;
	struct neighbour *n;
	struct arphdr *parp;
	u8 *arpptr, *sha;
	__be32 sip, tip;

	BR_INPUT_SKB_CB(skb)->proxyarp_replied = false;

	if ((dev->flags & IFF_NOARP) ||
	    !pskb_may_pull(skb, arp_hdr_len(dev)))
		return;

	parp = arp_hdr(skb);

	if (parp->ar_pro != htons(ETH_P_IP) ||
	    parp->ar_op != htons(ARPOP_REQUEST) ||
	    parp->ar_hln != dev->addr_len ||
	    parp->ar_pln != 4)
		return;

	arpptr = (u8 *)parp + sizeof(struct arphdr);
	sha = arpptr;
	arpptr += dev->addr_len;	/* sha */
	memcpy(&sip, arpptr, sizeof(sip));
	arpptr += sizeof(sip);
	arpptr += dev->addr_len;	/* tha */
	memcpy(&tip, arpptr, sizeof(tip));

	if (ipv4_is_loopback(tip) ||
	    ipv4_is_multicast(tip))
		return;

	n = neigh_lookup(&arp_tbl, &tip, dev);
	if (n) {
		struct net_bridge_fdb_entry *f;

		if (!(n->nud_state & NUD_VALID)) {
			neigh_release(n);
			return;
		}

		f = br_fdb_find_rcu(br, n->ha, vid);
		if (f && ((p->flags & BR_PROXYARP) ||
			  (f->dst && (f->dst->flags & BR_PROXYARP_WIFI)))) {
			arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip,
				 sha, n->ha, sha);
			BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
		}

		neigh_release(n);
	}
}

/* note: already called with rcu_read_lock */
int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
{
	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
	enum br_pkt_type pkt_type = BR_PKT_UNICAST;
	struct net_bridge_fdb_entry *dst = NULL;
	struct net_bridge_mdb_entry *mdst;
	bool local_rcv, mcast_hit = false;
	const unsigned char *dest;
	struct net_bridge *br;
	u16 vid = 0;

	if (!p || p->state == BR_STATE_DISABLED)
		goto drop;

	if (!br_allowed_ingress(p->br, nbp_vlan_group_rcu(p), skb, &vid))
		goto out;

	nbp_switchdev_frame_mark(p, skb);

	/* insert into forwarding database after filtering to avoid spoofing */
	br = p->br;
	if (p->flags & BR_LEARNING)
		br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false);

	local_rcv = !!(br->dev->flags & IFF_PROMISC);
	dest = eth_hdr(skb)->h_dest;
	if (is_multicast_ether_addr(dest)) {
		/* by definition the broadcast is also a multicast address */
		if (is_broadcast_ether_addr(dest)) {
			pkt_type = BR_PKT_BROADCAST;
			local_rcv = true;
		} else {
			pkt_type = BR_PKT_MULTICAST;
			if (br_multicast_rcv(br, p, skb, vid))
				goto drop;
		}
	}

	if (p->state == BR_STATE_LEARNING)
		goto drop;

	BR_INPUT_SKB_CB(skb)->brdev = br->dev;

	if (IS_ENABLED(CONFIG_INET) && skb->protocol == htons(ETH_P_ARP))
		br_do_proxy_arp(skb, br, vid, p);

	switch (pkt_type) {
	case BR_PKT_MULTICAST:
		mdst = br_mdb_get(br, skb, vid);
		if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
		    br_multicast_querier_exists(br, eth_hdr(skb))) {
			if ((mdst && mdst->mglist) ||
			    br_multicast_is_router(br)) {
				local_rcv = true;
				br->dev->stats.multicast++;
			}
			mcast_hit = true;
		} else {
			local_rcv = true;
			br->dev->stats.multicast++;
		}
		break;
	case BR_PKT_UNICAST:
		dst = br_fdb_find_rcu(br, dest, vid);
	default:
		break;
	}

	if (dst) {
		unsigned long now = jiffies;

		if (dst->is_local)
			return br_pass_frame_up(skb);

		if (now != dst->used)
			dst->used = now;
		br_forward(dst->dst, skb, local_rcv, false);
	} else {
		if (!mcast_hit)
			br_flood(br, skb, pkt_type, local_rcv, false);
		else
			br_multicast_flood(mdst, skb, local_rcv, false);
	}

	if (local_rcv)
		return br_pass_frame_up(skb);

out:
	return 0;
drop:
	kfree_skb(skb);
	goto out;
}
EXPORT_SYMBOL_GPL(br_handle_frame_finish);

static void __br_handle_local_finish(struct sk_buff *skb)
{
	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
	u16 vid = 0;

	/* check if vlan is allowed, to avoid spoofing */
	if (p->flags & BR_LEARNING && br_should_learn(p, skb, &vid))
		br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, false);
}

/* note: already called with rcu_read_lock */
static int br_handle_local_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
{
	struct net_bridge_port *p = br_port_get_rcu(skb->dev);

	__br_handle_local_finish(skb);

	BR_INPUT_SKB_CB(skb)->brdev = p->br->dev;
	br_pass_frame_up(skb);
	return 0;
}

/*
 * Return NULL if skb is handled
 * note: already called with rcu_read_lock
 */
rx_handler_result_t br_handle_frame(struct sk_buff **pskb)
{
	struct net_bridge_port *p;
	struct sk_buff *skb = *pskb;
	const unsigned char *dest = eth_hdr(skb)->h_dest;
	br_should_route_hook_t *rhook;

	if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
		return RX_HANDLER_PASS;

	if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
		goto drop;

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (!skb)
		return RX_HANDLER_CONSUMED;

	p = br_port_get_rcu(skb->dev);
	if (p->flags & BR_VLAN_TUNNEL) {
		if (br_handle_ingress_vlan_tunnel(skb, p,
						  nbp_vlan_group_rcu(p)))
			goto drop;
	}

	if (unlikely(is_link_local_ether_addr(dest))) {
		u16 fwd_mask = p->br->group_fwd_mask_required;

		/*
		 * See IEEE 802.1D Table 7-10 Reserved addresses
		 *
		 * Assignment		 		Value
		 * Bridge Group Address		01-80-C2-00-00-00
		 * (MAC Control) 802.3		01-80-C2-00-00-01
		 * (Link Aggregation) 802.3	01-80-C2-00-00-02
		 * 802.1X PAE address		01-80-C2-00-00-03
		 *
		 * 802.1AB LLDP 		01-80-C2-00-00-0E
		 *
		 * Others reserved for future standardization
		 */
		switch (dest[5]) {
		case 0x00:	/* Bridge Group Address */
			/* If STP is turned off,
			   then must forward to keep loop detection */
			if (p->br->stp_enabled == BR_NO_STP ||
			    fwd_mask & (1u << dest[5]))
				goto forward;
			*pskb = skb;
			__br_handle_local_finish(skb);
			return RX_HANDLER_PASS;

		case 0x01:	/* IEEE MAC (Pause) */
			goto drop;

		case 0x0E:	/* 802.1AB LLDP */
			fwd_mask |= p->br->group_fwd_mask;
			if (fwd_mask & (1u << dest[5]))
				goto forward;
			*pskb = skb;
			__br_handle_local_finish(skb);
			return RX_HANDLER_PASS;

		default:
			/* Allow selective forwarding for most other protocols */
			fwd_mask |= p->br->group_fwd_mask;
			if (fwd_mask & (1u << dest[5]))
				goto forward;
		}

		/* Deliver packet to local host only */
		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, dev_net(skb->dev),
			NULL, skb, skb->dev, NULL, br_handle_local_finish);
		return RX_HANDLER_CONSUMED;
	}

forward:
	switch (p->state) {
	case BR_STATE_FORWARDING:
		rhook = rcu_dereference(br_should_route_hook);
		if (rhook) {
			if ((*rhook)(skb)) {
				*pskb = skb;
				return RX_HANDLER_PASS;
			}
			dest = eth_hdr(skb)->h_dest;
		}
		/* fall through */
	case BR_STATE_LEARNING:
		if (ether_addr_equal(p->br->dev->dev_addr, dest))
			skb->pkt_type = PACKET_HOST;

		NF_HOOK(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING,
			dev_net(skb->dev), NULL, skb, skb->dev, NULL,
			br_handle_frame_finish);
		break;
	default:
drop:
		kfree_skb(skb);
	}
	return RX_HANDLER_CONSUMED;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Handle incoming frames
	3	* Linux ethernet bridge
	4	*
	5	* Authors:
	6	* Lennert Buytenhek <buytenh@gnu.org>
	7	*
1da177e4 LT	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version
	11	* 2 of the License, or (at your option) any later version.
	12	*/
	13
5a0e3ad6	14	#include <linux/slab.h>
1da177e4 LT	15	#include <linux/kernel.h>
	16	#include <linux/netdevice.h>
	17	#include <linux/etherdevice.h>
	18	#include <linux/netfilter_bridge.h>
95850116 KP	19	#include <linux/neighbour.h>
95850116 KP	20	#include <net/arp.h>
bc3b2d7f	21	#include <linux/export.h>
a37b85c9	22	#include <linux/rculist.h>
1da177e4	23	#include "br_private.h"
11538d03	24	#include "br_private_tunnel.h"
1da177e4	25
a386f990 ED	26	/* Hook for brouter */
	27	br_should_route_hook_t __rcu *br_should_route_hook __read_mostly;
	28	EXPORT_SYMBOL(br_should_route_hook);
	29
0c4b51f0 EB	30	static int
0c4b51f0 EB	31	br_netif_receive_skb(struct net net, struct sock sk, struct sk_buff *skb)
04eb4489	32	{
a13b2082	33	br_drop_fake_rtable(skb);
04eb4489 EB	34	return netif_receive_skb(skb);
	35	}
	36
68b7c895	37	static int br_pass_frame_up(struct sk_buff *skb)
1da177e4	38	{
68b7c895	39	struct net_device indev, brdev = BR_INPUT_SKB_CB(skb)->brdev;
14bb4789	40	struct net_bridge *br = netdev_priv(brdev);
2594e906	41	struct net_bridge_vlan_group *vg;
8f84985f	42	struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);
1da177e4	43
406818ff	44	u64_stats_update_begin(&brstats->syncp);
14bb4789	45	brstats->rx_packets++;
14bb4789	46	brstats->rx_bytes += skb->len;
406818ff	47	u64_stats_update_end(&brstats->syncp);
1da177e4	48
907b1e6e	49	vg = br_vlan_group_rcu(br);
85f46c6b VY	50	/* Bridge is just like any other port. Make sure the
	51	* packet is allowed except in promisc modue when someone
	52	* may be running packet capture.
	53	*/
	54	if (!(brdev->flags & IFF_PROMISC) &&
2594e906	55	!br_allowed_egress(vg, skb)) {
85f46c6b VY	56	kfree_skb(skb);
	57	return NET_RX_DROP;
	58	}
	59
1da177e4	60	indev = skb->dev;
a339f1c8	61	skb->dev = brdev;
11538d03	62	skb = br_handle_vlan(br, NULL, vg, skb);
fc92f745 VY	63	if (!skb)
fc92f745 VY	64	return NET_RX_DROP;
1080ab95	65	/* update the multicast stats if the packet is IGMP/MLD */
a65056ec	66	br_multicast_count(br, NULL, skb, br_multicast_igmp_type(skb),
1080ab95	67	BR_MCAST_DIR_TX);
1da177e4	68
29a26a56 EB	69	return NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN,
29a26a56 EB	70	dev_net(indev), NULL, skb, indev, NULL,
04eb4489	71	br_netif_receive_skb);
1da177e4 LT	72	}
1da177e4 LT	73
95850116	74	static void br_do_proxy_arp(struct sk_buff skb, struct net_bridge br,
842a9ae0	75	u16 vid, struct net_bridge_port *p)
95850116 KP	76	{
	77	struct net_device *dev = br->dev;
	78	struct neighbour *n;
	79	struct arphdr *parp;
	80	u8 arpptr, sha;
	81	__be32 sip, tip;
	82
842a9ae0 JM	83	BR_INPUT_SKB_CB(skb)->proxyarp_replied = false;
842a9ae0 JM	84
85a3d4a9 NA	85	if ((dev->flags & IFF_NOARP) \|\|
85a3d4a9 NA	86	!pskb_may_pull(skb, arp_hdr_len(dev)))
95850116 KP	87	return;
95850116 KP	88
95850116 KP	89	parp = arp_hdr(skb);
	90
	91	if (parp->ar_pro != htons(ETH_P_IP) \|\|
	92	parp->ar_op != htons(ARPOP_REQUEST) \|\|
	93	parp->ar_hln != dev->addr_len \|\|
	94	parp->ar_pln != 4)
	95	return;
	96
	97	arpptr = (u8 *)parp + sizeof(struct arphdr);
	98	sha = arpptr;
	99	arpptr += dev->addr_len; /* sha */
	100	memcpy(&sip, arpptr, sizeof(sip));
	101	arpptr += sizeof(sip);
	102	arpptr += dev->addr_len; /* tha */
	103	memcpy(&tip, arpptr, sizeof(tip));
	104
	105	if (ipv4_is_loopback(tip) \|\|
	106	ipv4_is_multicast(tip))
	107	return;
	108
	109	n = neigh_lookup(&arp_tbl, &tip, dev);
	110	if (n) {
	111	struct net_bridge_fdb_entry *f;
	112
	113	if (!(n->nud_state & NUD_VALID)) {
	114	neigh_release(n);
	115	return;
	116	}
	117
bfd0aeac	118	f = br_fdb_find_rcu(br, n->ha, vid);
842a9ae0 JM	119	if (f && ((p->flags & BR_PROXYARP) \|\|
842a9ae0 JM	120	(f->dst && (f->dst->flags & BR_PROXYARP_WIFI)))) {
95850116 KP	121	arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip,
95850116 KP	122	sha, n->ha, sha);
842a9ae0 JM	123	BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
842a9ae0 JM	124	}
95850116 KP	125
	126	neigh_release(n);
	127	}
	128	}
	129
eeaf61d8	130	/* note: already called with rcu_read_lock */
0c4b51f0	131	int br_handle_frame_finish(struct net net, struct sock sk, struct sk_buff *skb)
1da177e4	132	{
f350a0a8	133	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
8addd5e7	134	enum br_pkt_type pkt_type = BR_PKT_UNICAST;
46c0772d	135	struct net_bridge_fdb_entry *dst = NULL;
c4fcb78c	136	struct net_bridge_mdb_entry *mdst;
8addd5e7	137	bool local_rcv, mcast_hit = false;
31a4562d	138	const unsigned char *dest;
46c0772d	139	struct net_bridge *br;
78851988	140	u16 vid = 0;
1da177e4	141
b3f1be4b SH	142	if (!p \|\| p->state == BR_STATE_DISABLED)
	143	goto drop;
	144
907b1e6e	145	if (!br_allowed_ingress(p->br, nbp_vlan_group_rcu(p), skb, &vid))
eb707618	146	goto out;
a37b85c9	147
6bc506b4 IS	148	nbp_switchdev_frame_mark(p, skb);
6bc506b4 IS	149
85967bb4	150	/* insert into forwarding database after filtering to avoid spoofing */
b3f1be4b	151	br = p->br;
9ba18891	152	if (p->flags & BR_LEARNING)
a5642ab4	153	br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false);
85967bb4	154
8addd5e7	155	local_rcv = !!(br->dev->flags & IFF_PROMISC);
31a4562d	156	dest = eth_hdr(skb)->h_dest;
8addd5e7 NA	157	if (is_multicast_ether_addr(dest)) {
	158	/* by definition the broadcast is also a multicast address */
	159	if (is_broadcast_ether_addr(dest)) {
	160	pkt_type = BR_PKT_BROADCAST;
	161	local_rcv = true;
	162	} else {
	163	pkt_type = BR_PKT_MULTICAST;
	164	if (br_multicast_rcv(br, p, skb, vid))
	165	goto drop;
	166	}
	167	}
c4fcb78c	168
b3f1be4b SH	169	if (p->state == BR_STATE_LEARNING)
b3f1be4b SH	170	goto drop;
0e5eabac	171
68b7c895 HX	172	BR_INPUT_SKB_CB(skb)->brdev = br->dev;
68b7c895 HX	173
842a9ae0 JM	174	if (IS_ENABLED(CONFIG_INET) && skb->protocol == htons(ETH_P_ARP))
842a9ae0 JM	175	br_do_proxy_arp(skb, br, vid, p);
95850116	176
8addd5e7 NA	177	switch (pkt_type) {
8addd5e7 NA	178	case BR_PKT_MULTICAST:
fbca58a2	179	mdst = br_mdb_get(br, skb, vid);
b00589af	180	if ((mdst \|\| BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
cc0fdd80	181	br_multicast_querier_exists(br, eth_hdr(skb))) {
8a870178	182	if ((mdst && mdst->mglist) \|\|
e151aab9	183	br_multicast_is_router(br)) {
b35c5f63	184	local_rcv = true;
e151aab9 NA	185	br->dev->stats.multicast++;
	186	}
	187	mcast_hit = true;
46c0772d	188	} else {
b35c5f63	189	local_rcv = true;
e151aab9	190	br->dev->stats.multicast++;
46c0772d	191	}
8addd5e7 NA	192	break;
8addd5e7 NA	193	case BR_PKT_UNICAST:
bfd0aeac	194	dst = br_fdb_find_rcu(br, dest, vid);
8addd5e7 NA	195	default:
8addd5e7 NA	196	break;
1da177e4 LT	197	}
1da177e4 LT	198
e151aab9	199	if (dst) {
ca6d4480	200	unsigned long now = jiffies;
ca6d4480	201
8addd5e7 NA	202	if (dst->is_local)
	203	return br_pass_frame_up(skb);
	204
ca6d4480	205	if (now != dst->used)
ca6d4480	206	dst->used = now;
37b090e6	207	br_forward(dst->dst, skb, local_rcv, false);
e151aab9 NA	208	} else {
e151aab9 NA	209	if (!mcast_hit)
8addd5e7	210	br_flood(br, skb, pkt_type, local_rcv, false);
e151aab9	211	else
37b090e6	212	br_multicast_flood(mdst, skb, local_rcv, false);
e081e1e3	213	}
1da177e4	214
b35c5f63 NA	215	if (local_rcv)
b35c5f63 NA	216	return br_pass_frame_up(skb);
87557c18	217
1da177e4 LT	218	out:
1da177e4 LT	219	return 0;
b3f1be4b SH	220	drop:
	221	kfree_skb(skb);
	222	goto out;
1da177e4	223	}
34666d46	224	EXPORT_SYMBOL_GPL(br_handle_frame_finish);
1da177e4	225
56fae404	226	static void __br_handle_local_finish(struct sk_buff *skb)
cf0f02d0	227	{
f350a0a8	228	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
2ba071ec	229	u16 vid = 0;
cf0f02d0	230
e0d7968a TM	231	/* check if vlan is allowed, to avoid spoofing */
e0d7968a TM	232	if (p->flags & BR_LEARNING && br_should_learn(p, skb, &vid))
a5642ab4	233	br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, false);
56fae404 IS	234	}
	235
	236	/* note: already called with rcu_read_lock */
	237	static int br_handle_local_finish(struct net net, struct sock sk, struct sk_buff *skb)
	238	{
	239	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
	240
	241	__br_handle_local_finish(skb);
8626c56c FW	242
	243	BR_INPUT_SKB_CB(skb)->brdev = p->br->dev;
	244	br_pass_frame_up(skb);
	245	return 0;
cf0f02d0 SH	246	}
cf0f02d0 SH	247
1da177e4	248	/*
6229e362	249	* Return NULL if skb is handled
eeaf61d8	250	* note: already called with rcu_read_lock
1da177e4	251	*/
8a4eb573	252	rx_handler_result_t br_handle_frame(struct sk_buff **pskb)
1da177e4	253	{
ab95bfe0	254	struct net_bridge_port *p;
8a4eb573	255	struct sk_buff skb = pskb;
1da177e4	256	const unsigned char *dest = eth_hdr(skb)->h_dest;
a386f990	257	br_should_route_hook_t *rhook;
1da177e4	258
c2368e79	259	if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
8a4eb573	260	return RX_HANDLER_PASS;
ab95bfe0	261
1da177e4	262	if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
467aea0d	263	goto drop;
1da177e4	264
7b995651 HX	265	skb = skb_share_check(skb, GFP_ATOMIC);
7b995651 HX	266	if (!skb)
8a4eb573	267	return RX_HANDLER_CONSUMED;
7b995651	268
f350a0a8	269	p = br_port_get_rcu(skb->dev);
11538d03 RP	270	if (p->flags & BR_VLAN_TUNNEL) {
	271	if (br_handle_ingress_vlan_tunnel(skb, p,
	272	nbp_vlan_group_rcu(p)))
	273	goto drop;
	274	}
ab95bfe0	275
46acc460	276	if (unlikely(is_link_local_ether_addr(dest))) {
f2808d22 TM	277	u16 fwd_mask = p->br->group_fwd_mask_required;
f2808d22 TM	278
515853cc	279	/*
	280	* See IEEE 802.1D Table 7-10 Reserved addresses
	281	*
	282	* Assignment Value
	283	* Bridge Group Address 01-80-C2-00-00-00
	284	* (MAC Control) 802.3 01-80-C2-00-00-01
	285	* (Link Aggregation) 802.3 01-80-C2-00-00-02
	286	* 802.1X PAE address 01-80-C2-00-00-03
	287	*
	288	* 802.1AB LLDP 01-80-C2-00-00-0E
	289	*
	290	* Others reserved for future standardization
	291	*/
	292	switch (dest[5]) {
	293	case 0x00: /* Bridge Group Address */
	294	/* If STP is turned off,
	295	then must forward to keep loop detection */
f2808d22 TM	296	if (p->br->stp_enabled == BR_NO_STP \|\|
f2808d22 TM	297	fwd_mask & (1u << dest[5]))
515853cc	298	goto forward;
56fae404 IS	299	*pskb = skb;
	300	__br_handle_local_finish(skb);
	301	return RX_HANDLER_PASS;
515853cc	302
515853cc	303	case 0x01: /* IEEE MAC (Pause) */
2111f8b9 SH	304	goto drop;
2111f8b9 SH	305
baedbe55 IS	306	case 0x0E: /* 802.1AB LLDP */
	307	fwd_mask \|= p->br->group_fwd_mask;
	308	if (fwd_mask & (1u << dest[5]))
	309	goto forward;
	310	*pskb = skb;
	311	__br_handle_local_finish(skb);
	312	return RX_HANDLER_PASS;
	313
515853cc	314	default:
515853cc	315	/* Allow selective forwarding for most other protocols */
f2808d22 TM	316	fwd_mask \|= p->br->group_fwd_mask;
f2808d22 TM	317	if (fwd_mask & (1u << dest[5]))
515853cc	318	goto forward;
515853cc	319	}
a598f6ae	320
515853cc	321	/* Deliver packet to local host only */
8626c56c FW	322	NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, dev_net(skb->dev),
	323	NULL, skb, skb->dev, NULL, br_handle_local_finish);
	324	return RX_HANDLER_CONSUMED;
2111f8b9	325	}
1da177e4	326
a598f6ae	327	forward:
467aea0d SH	328	switch (p->state) {
467aea0d SH	329	case BR_STATE_FORWARDING:
82de382c	330	rhook = rcu_dereference(br_should_route_hook);
a386f990	331	if (rhook) {
8a4eb573 JP	332	if ((*rhook)(skb)) {
	333	*pskb = skb;
	334	return RX_HANDLER_PASS;
	335	}
1da177e4 LT	336	dest = eth_hdr(skb)->h_dest;
1da177e4 LT	337	}
467aea0d SH	338	/* fall through */
467aea0d SH	339	case BR_STATE_LEARNING:
9a7b6ef9	340	if (ether_addr_equal(p->br->dev->dev_addr, dest))
1da177e4 LT	341	skb->pkt_type = PACKET_HOST;
1da177e4 LT	342
29a26a56 EB	343	NF_HOOK(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING,
29a26a56 EB	344	dev_net(skb->dev), NULL, skb, skb->dev, NULL,
1da177e4	345	br_handle_frame_finish);
467aea0d SH	346	break;
	347	default:
	348	drop:
	349	kfree_skb(skb);
1da177e4	350	}
8a4eb573	351	return RX_HANDLER_CONSUMED;
1da177e4	352	}