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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	Handle incoming frames
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 */

#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/netfilter_bridge.h>
#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
#include <net/netfilter/nf_queue.h>
#endif
#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"

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);
}

/* 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;
	BR_INPUT_SKB_CB(skb)->src_port_isolated = !!(p->flags & BR_ISOLATED);

	if (IS_ENABLED(CONFIG_INET) &&
	    (skb->protocol == htons(ETH_P_ARP) ||
	     skb->protocol == htons(ETH_P_RARP))) {
		br_do_proxy_suppress_arp(skb, br, vid, p);
	} else if (IS_ENABLED(CONFIG_IPV6) &&
		   skb->protocol == htons(ETH_P_IPV6) &&
		   br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) &&
		   pskb_may_pull(skb, sizeof(struct ipv6hdr) +
				 sizeof(struct nd_msg)) &&
		   ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) {
			struct nd_msg *msg, _msg;

			msg = br_is_nd_neigh_msg(skb, &_msg);
			if (msg)
				br_do_suppress_nd(skb, br, vid, p, msg);
	}

	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->host_joined) ||
			    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_opt_get(p->br, BROPT_NO_LL_LEARN) &&
	    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)
{
	__br_handle_local_finish(skb);

	/* return 1 to signal the okfn() was called so it's ok to use the skb */
	return 1;
}

static int nf_hook_bridge_pre(struct sk_buff *skb, struct sk_buff **pskb)
{
#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
	struct nf_hook_entries *e = NULL;
	struct nf_hook_state state;
	unsigned int verdict, i;
	struct net *net;
	int ret;

	net = dev_net(skb->dev);
#ifdef HAVE_JUMP_LABEL
	if (!static_key_false(&nf_hooks_needed[NFPROTO_BRIDGE][NF_BR_PRE_ROUTING]))
		goto frame_finish;
#endif

	e = rcu_dereference(net->nf.hooks_bridge[NF_BR_PRE_ROUTING]);
	if (!e)
		goto frame_finish;

	nf_hook_state_init(&state, NF_BR_PRE_ROUTING,
			   NFPROTO_BRIDGE, skb->dev, NULL, NULL,
			   net, br_handle_frame_finish);

	for (i = 0; i < e->num_hook_entries; i++) {
		verdict = nf_hook_entry_hookfn(&e->hooks[i], skb, &state);
		switch (verdict & NF_VERDICT_MASK) {
		case NF_ACCEPT:
			if (BR_INPUT_SKB_CB(skb)->br_netfilter_broute) {
				*pskb = skb;
				return RX_HANDLER_PASS;
			}
			break;
		case NF_DROP:
			kfree_skb(skb);
			return RX_HANDLER_CONSUMED;
		case NF_QUEUE:
			ret = nf_queue(skb, &state, e, i, verdict);
			if (ret == 1)
				continue;
			return RX_HANDLER_CONSUMED;
		default: /* STOLEN */
			return RX_HANDLER_CONSUMED;
		}
	}
frame_finish:
	net = dev_net(skb->dev);
	br_handle_frame_finish(net, NULL, skb);
#else
	br_handle_frame_finish(dev_net(skb->dev), NULL, skb);
#endif
	return RX_HANDLER_CONSUMED;
}

/*
 * 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;

	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;

	memset(skb->cb, 0, sizeof(struct br_input_skb_cb));

	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
		 */
		fwd_mask |= p->group_fwd_mask;
		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;
		}

		/* The else clause should be hit when nf_hook():
		 *   - returns < 0 (drop/error)
		 *   - returns = 0 (stolen/nf_queue)
		 * Thus return 1 from the okfn() to signal the skb is ok to pass
		 */
		if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN,
			    dev_net(skb->dev), NULL, skb, skb->dev, NULL,
			    br_handle_local_finish) == 1) {
			return RX_HANDLER_PASS;
		} else {
			return RX_HANDLER_CONSUMED;
		}
	}

forward:
	switch (p->state) {
	case BR_STATE_FORWARDING:
	case BR_STATE_LEARNING:
		if (ether_addr_equal(p->br->dev->dev_addr, dest))
			skb->pkt_type = PACKET_HOST;

		return nf_hook_bridge_pre(skb, pskb);
	default:
drop:
		kfree_skb(skb);
	}
	return RX_HANDLER_CONSUMED;
}
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* Handle incoming frames
	4	* Linux ethernet bridge
	5	*
	6	* Authors:
	7	* Lennert Buytenhek <buytenh@gnu.org>
1da177e4 LT	8	*/
1da177e4 LT	9
5a0e3ad6	10	#include <linux/slab.h>
1da177e4 LT	11	#include <linux/kernel.h>
	12	#include <linux/netdevice.h>
	13	#include <linux/etherdevice.h>
	14	#include <linux/netfilter_bridge.h>
dc2f4189	15	#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
971502d7	16	#include <net/netfilter/nf_queue.h>
dc2f4189	17	#endif
95850116 KP	18	#include <linux/neighbour.h>
95850116 KP	19	#include <net/arp.h>
bc3b2d7f	20	#include <linux/export.h>
a37b85c9	21	#include <linux/rculist.h>
1da177e4	22	#include "br_private.h"
11538d03	23	#include "br_private_tunnel.h"
1da177e4	24
0c4b51f0 EB	25	static int
0c4b51f0 EB	26	br_netif_receive_skb(struct net net, struct sock sk, struct sk_buff *skb)
04eb4489	27	{
a13b2082	28	br_drop_fake_rtable(skb);
04eb4489 EB	29	return netif_receive_skb(skb);
	30	}
	31
68b7c895	32	static int br_pass_frame_up(struct sk_buff *skb)
1da177e4	33	{
68b7c895	34	struct net_device indev, brdev = BR_INPUT_SKB_CB(skb)->brdev;
14bb4789	35	struct net_bridge *br = netdev_priv(brdev);
2594e906	36	struct net_bridge_vlan_group *vg;
8f84985f	37	struct pcpu_sw_netstats *brstats = this_cpu_ptr(br->stats);
1da177e4	38
406818ff	39	u64_stats_update_begin(&brstats->syncp);
14bb4789	40	brstats->rx_packets++;
14bb4789	41	brstats->rx_bytes += skb->len;
406818ff	42	u64_stats_update_end(&brstats->syncp);
1da177e4	43
907b1e6e	44	vg = br_vlan_group_rcu(br);
85f46c6b VY	45	/* Bridge is just like any other port. Make sure the
	46	* packet is allowed except in promisc modue when someone
	47	* may be running packet capture.
	48	*/
	49	if (!(brdev->flags & IFF_PROMISC) &&
2594e906	50	!br_allowed_egress(vg, skb)) {
85f46c6b VY	51	kfree_skb(skb);
	52	return NET_RX_DROP;
	53	}
	54
1da177e4	55	indev = skb->dev;
a339f1c8	56	skb->dev = brdev;
11538d03	57	skb = br_handle_vlan(br, NULL, vg, skb);
fc92f745 VY	58	if (!skb)
fc92f745 VY	59	return NET_RX_DROP;
1080ab95	60	/* update the multicast stats if the packet is IGMP/MLD */
a65056ec	61	br_multicast_count(br, NULL, skb, br_multicast_igmp_type(skb),
1080ab95	62	BR_MCAST_DIR_TX);
1da177e4	63
29a26a56 EB	64	return NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN,
29a26a56 EB	65	dev_net(indev), NULL, skb, indev, NULL,
04eb4489	66	br_netif_receive_skb);
1da177e4 LT	67	}
1da177e4 LT	68
eeaf61d8	69	/* note: already called with rcu_read_lock */
0c4b51f0	70	int br_handle_frame_finish(struct net net, struct sock sk, struct sk_buff *skb)
1da177e4	71	{
f350a0a8	72	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
8addd5e7	73	enum br_pkt_type pkt_type = BR_PKT_UNICAST;
46c0772d	74	struct net_bridge_fdb_entry *dst = NULL;
c4fcb78c	75	struct net_bridge_mdb_entry *mdst;
8addd5e7	76	bool local_rcv, mcast_hit = false;
31a4562d	77	const unsigned char *dest;
46c0772d	78	struct net_bridge *br;
78851988	79	u16 vid = 0;
1da177e4	80
b3f1be4b SH	81	if (!p \|\| p->state == BR_STATE_DISABLED)
	82	goto drop;
	83
907b1e6e	84	if (!br_allowed_ingress(p->br, nbp_vlan_group_rcu(p), skb, &vid))
eb707618	85	goto out;
a37b85c9	86
6bc506b4 IS	87	nbp_switchdev_frame_mark(p, skb);
6bc506b4 IS	88
85967bb4	89	/* insert into forwarding database after filtering to avoid spoofing */
b3f1be4b	90	br = p->br;
9ba18891	91	if (p->flags & BR_LEARNING)
a5642ab4	92	br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false);
85967bb4	93
8addd5e7	94	local_rcv = !!(br->dev->flags & IFF_PROMISC);
31a4562d	95	dest = eth_hdr(skb)->h_dest;
8addd5e7 NA	96	if (is_multicast_ether_addr(dest)) {
	97	/* by definition the broadcast is also a multicast address */
	98	if (is_broadcast_ether_addr(dest)) {
	99	pkt_type = BR_PKT_BROADCAST;
	100	local_rcv = true;
	101	} else {
	102	pkt_type = BR_PKT_MULTICAST;
	103	if (br_multicast_rcv(br, p, skb, vid))
	104	goto drop;
	105	}
	106	}
c4fcb78c	107
b3f1be4b SH	108	if (p->state == BR_STATE_LEARNING)
b3f1be4b SH	109	goto drop;
0e5eabac	110
68b7c895	111	BR_INPUT_SKB_CB(skb)->brdev = br->dev;
7d850abd	112	BR_INPUT_SKB_CB(skb)->src_port_isolated = !!(p->flags & BR_ISOLATED);
68b7c895	113
057658cb RP	114	if (IS_ENABLED(CONFIG_INET) &&
	115	(skb->protocol == htons(ETH_P_ARP) \|\|
	116	skb->protocol == htons(ETH_P_RARP))) {
	117	br_do_proxy_suppress_arp(skb, br, vid, p);
ed842fae RP	118	} else if (IS_ENABLED(CONFIG_IPV6) &&
ed842fae RP	119	skb->protocol == htons(ETH_P_IPV6) &&
c69c2cd4	120	br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) &&
ed842fae RP	121	pskb_may_pull(skb, sizeof(struct ipv6hdr) +
	122	sizeof(struct nd_msg)) &&
	123	ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) {
	124	struct nd_msg *msg, _msg;
	125
	126	msg = br_is_nd_neigh_msg(skb, &_msg);
	127	if (msg)
	128	br_do_suppress_nd(skb, br, vid, p, msg);
057658cb	129	}
95850116	130
8addd5e7 NA	131	switch (pkt_type) {
8addd5e7 NA	132	case BR_PKT_MULTICAST:
fbca58a2	133	mdst = br_mdb_get(br, skb, vid);
b00589af	134	if ((mdst \|\| BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
cc0fdd80	135	br_multicast_querier_exists(br, eth_hdr(skb))) {
ff0fd34e	136	if ((mdst && mdst->host_joined) \|\|
e151aab9	137	br_multicast_is_router(br)) {
b35c5f63	138	local_rcv = true;
e151aab9 NA	139	br->dev->stats.multicast++;
	140	}
	141	mcast_hit = true;
46c0772d	142	} else {
b35c5f63	143	local_rcv = true;
e151aab9	144	br->dev->stats.multicast++;
46c0772d	145	}
8addd5e7 NA	146	break;
8addd5e7 NA	147	case BR_PKT_UNICAST:
bfd0aeac	148	dst = br_fdb_find_rcu(br, dest, vid);
8addd5e7 NA	149	default:
8addd5e7 NA	150	break;
1da177e4 LT	151	}
1da177e4 LT	152
e151aab9	153	if (dst) {
ca6d4480	154	unsigned long now = jiffies;
ca6d4480	155
8addd5e7 NA	156	if (dst->is_local)
	157	return br_pass_frame_up(skb);
	158
ca6d4480	159	if (now != dst->used)
ca6d4480	160	dst->used = now;
37b090e6	161	br_forward(dst->dst, skb, local_rcv, false);
e151aab9 NA	162	} else {
e151aab9 NA	163	if (!mcast_hit)
8addd5e7	164	br_flood(br, skb, pkt_type, local_rcv, false);
e151aab9	165	else
37b090e6	166	br_multicast_flood(mdst, skb, local_rcv, false);
e081e1e3	167	}
1da177e4	168
b35c5f63 NA	169	if (local_rcv)
b35c5f63 NA	170	return br_pass_frame_up(skb);
87557c18	171
1da177e4 LT	172	out:
1da177e4 LT	173	return 0;
b3f1be4b SH	174	drop:
	175	kfree_skb(skb);
	176	goto out;
1da177e4	177	}
34666d46	178	EXPORT_SYMBOL_GPL(br_handle_frame_finish);
1da177e4	179
56fae404	180	static void __br_handle_local_finish(struct sk_buff *skb)
cf0f02d0	181	{
f350a0a8	182	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
2ba071ec	183	u16 vid = 0;
cf0f02d0	184
e0d7968a	185	/* check if vlan is allowed, to avoid spoofing */
70e4272b NA	186	if ((p->flags & BR_LEARNING) &&
	187	!br_opt_get(p->br, BROPT_NO_LL_LEARN) &&
	188	br_should_learn(p, skb, &vid))
a5642ab4	189	br_fdb_update(p->br, p, eth_hdr(skb)->h_source, vid, false);
56fae404 IS	190	}
	191
	192	/* note: already called with rcu_read_lock */
	193	static int br_handle_local_finish(struct net net, struct sock sk, struct sk_buff *skb)
	194	{
56fae404	195	__br_handle_local_finish(skb);
8626c56c	196
3b2e2904 NA	197	/* return 1 to signal the okfn() was called so it's ok to use the skb */
3b2e2904 NA	198	return 1;
cf0f02d0 SH	199	}
cf0f02d0 SH	200
971502d7 FW	201	static int nf_hook_bridge_pre(struct sk_buff skb, struct sk_buff *pskb)
	202	{
	203	#ifdef CONFIG_NETFILTER_FAMILY_BRIDGE
	204	struct nf_hook_entries *e = NULL;
	205	struct nf_hook_state state;
	206	unsigned int verdict, i;
	207	struct net *net;
	208	int ret;
	209
	210	net = dev_net(skb->dev);
	211	#ifdef HAVE_JUMP_LABEL
	212	if (!static_key_false(&nf_hooks_needed[NFPROTO_BRIDGE][NF_BR_PRE_ROUTING]))
	213	goto frame_finish;
	214	#endif
	215
	216	e = rcu_dereference(net->nf.hooks_bridge[NF_BR_PRE_ROUTING]);
	217	if (!e)
	218	goto frame_finish;
	219
	220	nf_hook_state_init(&state, NF_BR_PRE_ROUTING,
	221	NFPROTO_BRIDGE, skb->dev, NULL, NULL,
	222	net, br_handle_frame_finish);
	223
	224	for (i = 0; i < e->num_hook_entries; i++) {
	225	verdict = nf_hook_entry_hookfn(&e->hooks[i], skb, &state);
	226	switch (verdict & NF_VERDICT_MASK) {
	227	case NF_ACCEPT:
223fd0ad FW	228	if (BR_INPUT_SKB_CB(skb)->br_netfilter_broute) {
	229	*pskb = skb;
	230	return RX_HANDLER_PASS;
	231	}
971502d7 FW	232	break;
	233	case NF_DROP:
	234	kfree_skb(skb);
	235	return RX_HANDLER_CONSUMED;
	236	case NF_QUEUE:
	237	ret = nf_queue(skb, &state, e, i, verdict);
	238	if (ret == 1)
	239	continue;
	240	return RX_HANDLER_CONSUMED;
	241	default: /* STOLEN */
	242	return RX_HANDLER_CONSUMED;
	243	}
	244	}
	245	frame_finish:
	246	net = dev_net(skb->dev);
	247	br_handle_frame_finish(net, NULL, skb);
	248	#else
	249	br_handle_frame_finish(dev_net(skb->dev), NULL, skb);
	250	#endif
	251	return RX_HANDLER_CONSUMED;
	252	}
	253
1da177e4	254	/*
6229e362	255	* Return NULL if skb is handled
eeaf61d8	256	* note: already called with rcu_read_lock
1da177e4	257	*/
8a4eb573	258	rx_handler_result_t br_handle_frame(struct sk_buff **pskb)
1da177e4	259	{
ab95bfe0	260	struct net_bridge_port *p;
8a4eb573	261	struct sk_buff skb = pskb;
1da177e4 LT	262	const unsigned char *dest = eth_hdr(skb)->h_dest;
1da177e4 LT	263
c2368e79	264	if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
8a4eb573	265	return RX_HANDLER_PASS;
ab95bfe0	266
1da177e4	267	if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
467aea0d	268	goto drop;
1da177e4	269
7b995651 HX	270	skb = skb_share_check(skb, GFP_ATOMIC);
7b995651 HX	271	if (!skb)
8a4eb573	272	return RX_HANDLER_CONSUMED;
7b995651	273
f12064d1 FW	274	memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
f12064d1 FW	275
f350a0a8	276	p = br_port_get_rcu(skb->dev);
11538d03 RP	277	if (p->flags & BR_VLAN_TUNNEL) {
	278	if (br_handle_ingress_vlan_tunnel(skb, p,
	279	nbp_vlan_group_rcu(p)))
	280	goto drop;
	281	}
ab95bfe0	282
46acc460	283	if (unlikely(is_link_local_ether_addr(dest))) {
f2808d22 TM	284	u16 fwd_mask = p->br->group_fwd_mask_required;
f2808d22 TM	285
515853cc	286	/*
	287	* See IEEE 802.1D Table 7-10 Reserved addresses
	288	*
	289	* Assignment Value
	290	* Bridge Group Address 01-80-C2-00-00-00
	291	* (MAC Control) 802.3 01-80-C2-00-00-01
	292	* (Link Aggregation) 802.3 01-80-C2-00-00-02
	293	* 802.1X PAE address 01-80-C2-00-00-03
	294	*
	295	* 802.1AB LLDP 01-80-C2-00-00-0E
	296	*
	297	* Others reserved for future standardization
	298	*/
5af48b59	299	fwd_mask \|= p->group_fwd_mask;
515853cc	300	switch (dest[5]) {
	301	case 0x00: /* Bridge Group Address */
	302	/* If STP is turned off,
	303	then must forward to keep loop detection */
f2808d22 TM	304	if (p->br->stp_enabled == BR_NO_STP \|\|
f2808d22 TM	305	fwd_mask & (1u << dest[5]))
515853cc	306	goto forward;
56fae404 IS	307	*pskb = skb;
	308	__br_handle_local_finish(skb);
	309	return RX_HANDLER_PASS;
515853cc	310
515853cc	311	case 0x01: /* IEEE MAC (Pause) */
2111f8b9 SH	312	goto drop;
2111f8b9 SH	313
baedbe55 IS	314	case 0x0E: /* 802.1AB LLDP */
	315	fwd_mask \|= p->br->group_fwd_mask;
	316	if (fwd_mask & (1u << dest[5]))
	317	goto forward;
	318	*pskb = skb;
	319	__br_handle_local_finish(skb);
	320	return RX_HANDLER_PASS;
	321
515853cc	322	default:
515853cc	323	/* Allow selective forwarding for most other protocols */
f2808d22 TM	324	fwd_mask \|= p->br->group_fwd_mask;
f2808d22 TM	325	if (fwd_mask & (1u << dest[5]))
515853cc	326	goto forward;
515853cc	327	}
a598f6ae	328
3b2e2904 NA	329	/* The else clause should be hit when nf_hook():
	330	* - returns < 0 (drop/error)
	331	* - returns = 0 (stolen/nf_queue)
	332	* Thus return 1 from the okfn() to signal the skb is ok to pass
	333	*/
	334	if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN,
	335	dev_net(skb->dev), NULL, skb, skb->dev, NULL,
	336	br_handle_local_finish) == 1) {
	337	return RX_HANDLER_PASS;
	338	} else {
	339	return RX_HANDLER_CONSUMED;
	340	}
2111f8b9	341	}
1da177e4	342
a598f6ae	343	forward:
467aea0d SH	344	switch (p->state) {
467aea0d SH	345	case BR_STATE_FORWARDING:
467aea0d	346	case BR_STATE_LEARNING:
9a7b6ef9	347	if (ether_addr_equal(p->br->dev->dev_addr, dest))
1da177e4 LT	348	skb->pkt_type = PACKET_HOST;
1da177e4 LT	349
971502d7	350	return nf_hook_bridge_pre(skb, pskb);
467aea0d SH	351	default:
	352	drop:
	353	kfree_skb(skb);
1da177e4	354	}
8a4eb573	355	return RX_HANDLER_CONSUMED;
1da177e4	356	}