[linux.git] / net / bridge / br_arp_nd_proxy.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Handle bridge arp/nd proxy/suppress
 *
 *  Copyright (C) 2017 Cumulus Networks
 *  Copyright (c) 2017 Roopa Prabhu <[email protected]>
 *
 *  Authors:
 *	Roopa Prabhu <[email protected]>
 */

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/neighbour.h>
#include <net/arp.h>
#include <linux/if_vlan.h>
#include <linux/inetdevice.h>
#include <net/addrconf.h>
#include <net/ipv6_stubs.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ip6_checksum.h>
#endif

#include "br_private.h"

void br_recalculate_neigh_suppress_enabled(struct net_bridge *br)
{
	struct net_bridge_port *p;
	bool neigh_suppress = false;

	list_for_each_entry(p, &br->port_list, list) {
		if (p->flags & BR_NEIGH_SUPPRESS) {
			neigh_suppress = true;
			break;
		}
	}

	br_opt_toggle(br, BROPT_NEIGH_SUPPRESS_ENABLED, neigh_suppress);
}

#if IS_ENABLED(CONFIG_INET)
static void br_arp_send(struct net_bridge *br, struct net_bridge_port *p,
			struct net_device *dev, __be32 dest_ip, __be32 src_ip,
			const unsigned char *dest_hw,
			const unsigned char *src_hw,
			const unsigned char *target_hw,
			__be16 vlan_proto, u16 vlan_tci)
{
	struct net_bridge_vlan_group *vg;
	struct sk_buff *skb;
	u16 pvid;

	netdev_dbg(dev, "arp send dev %s dst %pI4 dst_hw %pM src %pI4 src_hw %pM\n",
		   dev->name, &dest_ip, dest_hw, &src_ip, src_hw);

	if (!vlan_tci) {
		arp_send(ARPOP_REPLY, ETH_P_ARP, dest_ip, dev, src_ip,
			 dest_hw, src_hw, target_hw);
		return;
	}

	skb = arp_create(ARPOP_REPLY, ETH_P_ARP, dest_ip, dev, src_ip,
			 dest_hw, src_hw, target_hw);
	if (!skb)
		return;

	if (p)
		vg = nbp_vlan_group_rcu(p);
	else
		vg = br_vlan_group_rcu(br);
	pvid = br_get_pvid(vg);
	if (pvid == (vlan_tci & VLAN_VID_MASK))
		vlan_tci = 0;

	if (vlan_tci)
		__vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);

	if (p) {
		arp_xmit(skb);
	} else {
		skb_reset_mac_header(skb);
		__skb_pull(skb, skb_network_offset(skb));
		skb->ip_summed = CHECKSUM_UNNECESSARY;
		skb->pkt_type = PACKET_HOST;

		netif_rx_ni(skb);
	}
}

static int br_chk_addr_ip(struct net_device *dev,
			  struct netdev_nested_priv *priv)
{
	__be32 ip = *(__be32 *)priv->data;
	struct in_device *in_dev;
	__be32 addr = 0;

	in_dev = __in_dev_get_rcu(dev);
	if (in_dev)
		addr = inet_confirm_addr(dev_net(dev), in_dev, 0, ip,
					 RT_SCOPE_HOST);

	if (addr == ip)
		return 1;

	return 0;
}

static bool br_is_local_ip(struct net_device *dev, __be32 ip)
{
	struct netdev_nested_priv priv = {
		.data = (void *)&ip,
	};

	if (br_chk_addr_ip(dev, &priv))
		return true;

	/* check if ip is configured on upper dev */
	if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip, &priv))
		return true;

	return false;
}

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

	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0;

	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_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;

	if (br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) {
		if (p && (p->flags & BR_NEIGH_SUPPRESS))
			return;
		if (ipv4_is_zeronet(sip) || sip == tip) {
			/* prevent flooding to neigh suppress ports */
			BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
			return;
		}
	}

	if (parp->ar_op != htons(ARPOP_REQUEST))
		return;

	if (vid != 0) {
		vlandev = __vlan_find_dev_deep_rcu(br->dev, skb->vlan_proto,
						   vid);
		if (!vlandev)
			return;
	}

	if (br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) &&
	    br_is_local_ip(vlandev, tip)) {
		/* its our local ip, so don't proxy reply
		 * and don't forward to neigh suppress ports
		 */
		BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
		return;
	}

	n = neigh_lookup(&arp_tbl, &tip, vlandev);
	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) {
			bool replied = false;

			if ((p && (p->flags & BR_PROXYARP)) ||
			    (f->dst && (f->dst->flags & (BR_PROXYARP_WIFI |
							 BR_NEIGH_SUPPRESS)))) {
				if (!vid)
					br_arp_send(br, p, skb->dev, sip, tip,
						    sha, n->ha, sha, 0, 0);
				else
					br_arp_send(br, p, skb->dev, sip, tip,
						    sha, n->ha, sha,
						    skb->vlan_proto,
						    skb_vlan_tag_get(skb));
				replied = true;
			}

			/* If we have replied or as long as we know the
			 * mac, indicate to arp replied
			 */
			if (replied ||
			    br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED))
				BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
		}

		neigh_release(n);
	}
}
#endif

#if IS_ENABLED(CONFIG_IPV6)
struct nd_msg *br_is_nd_neigh_msg(struct sk_buff *skb, struct nd_msg *msg)
{
	struct nd_msg *m;

	m = skb_header_pointer(skb, skb_network_offset(skb) +
			       sizeof(struct ipv6hdr), sizeof(*msg), msg);
	if (!m)
		return NULL;

	if (m->icmph.icmp6_code != 0 ||
	    (m->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION &&
	     m->icmph.icmp6_type != NDISC_NEIGHBOUR_ADVERTISEMENT))
		return NULL;

	return m;
}

static void br_nd_send(struct net_bridge *br, struct net_bridge_port *p,
		       struct sk_buff *request, struct neighbour *n,
		       __be16 vlan_proto, u16 vlan_tci, struct nd_msg *ns)
{
	struct net_device *dev = request->dev;
	struct net_bridge_vlan_group *vg;
	struct sk_buff *reply;
	struct nd_msg *na;
	struct ipv6hdr *pip6;
	int na_olen = 8; /* opt hdr + ETH_ALEN for target */
	int ns_olen;
	int i, len;
	u8 *daddr;
	u16 pvid;

	if (!dev)
		return;

	len = LL_RESERVED_SPACE(dev) + sizeof(struct ipv6hdr) +
		sizeof(*na) + na_olen + dev->needed_tailroom;

	reply = alloc_skb(len, GFP_ATOMIC);
	if (!reply)
		return;

	reply->protocol = htons(ETH_P_IPV6);
	reply->dev = dev;
	skb_reserve(reply, LL_RESERVED_SPACE(dev));
	skb_push(reply, sizeof(struct ethhdr));
	skb_set_mac_header(reply, 0);

	daddr = eth_hdr(request)->h_source;

	/* Do we need option processing ? */
	ns_olen = request->len - (skb_network_offset(request) +
				  sizeof(struct ipv6hdr)) - sizeof(*ns);
	for (i = 0; i < ns_olen - 1; i += (ns->opt[i + 1] << 3)) {
		if (!ns->opt[i + 1]) {
			kfree_skb(reply);
			return;
		}
		if (ns->opt[i] == ND_OPT_SOURCE_LL_ADDR) {
			daddr = ns->opt + i + sizeof(struct nd_opt_hdr);
			break;
		}
	}

	/* Ethernet header */
	ether_addr_copy(eth_hdr(reply)->h_dest, daddr);
	ether_addr_copy(eth_hdr(reply)->h_source, n->ha);
	eth_hdr(reply)->h_proto = htons(ETH_P_IPV6);
	reply->protocol = htons(ETH_P_IPV6);

	skb_pull(reply, sizeof(struct ethhdr));
	skb_set_network_header(reply, 0);
	skb_put(reply, sizeof(struct ipv6hdr));

	/* IPv6 header */
	pip6 = ipv6_hdr(reply);
	memset(pip6, 0, sizeof(struct ipv6hdr));
	pip6->version = 6;
	pip6->priority = ipv6_hdr(request)->priority;
	pip6->nexthdr = IPPROTO_ICMPV6;
	pip6->hop_limit = 255;
	pip6->daddr = ipv6_hdr(request)->saddr;
	pip6->saddr = *(struct in6_addr *)n->primary_key;

	skb_pull(reply, sizeof(struct ipv6hdr));
	skb_set_transport_header(reply, 0);

	na = (struct nd_msg *)skb_put(reply, sizeof(*na) + na_olen);

	/* Neighbor Advertisement */
	memset(na, 0, sizeof(*na) + na_olen);
	na->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
	na->icmph.icmp6_router = (n->flags & NTF_ROUTER) ? 1 : 0;
	na->icmph.icmp6_override = 1;
	na->icmph.icmp6_solicited = 1;
	na->target = ns->target;
	ether_addr_copy(&na->opt[2], n->ha);
	na->opt[0] = ND_OPT_TARGET_LL_ADDR;
	na->opt[1] = na_olen >> 3;

	na->icmph.icmp6_cksum = csum_ipv6_magic(&pip6->saddr,
						&pip6->daddr,
						sizeof(*na) + na_olen,
						IPPROTO_ICMPV6,
						csum_partial(na, sizeof(*na) + na_olen, 0));

	pip6->payload_len = htons(sizeof(*na) + na_olen);

	skb_push(reply, sizeof(struct ipv6hdr));
	skb_push(reply, sizeof(struct ethhdr));

	reply->ip_summed = CHECKSUM_UNNECESSARY;

	if (p)
		vg = nbp_vlan_group_rcu(p);
	else
		vg = br_vlan_group_rcu(br);
	pvid = br_get_pvid(vg);
	if (pvid == (vlan_tci & VLAN_VID_MASK))
		vlan_tci = 0;

	if (vlan_tci)
		__vlan_hwaccel_put_tag(reply, vlan_proto, vlan_tci);

	netdev_dbg(dev, "nd send dev %s dst %pI6 dst_hw %pM src %pI6 src_hw %pM\n",
		   dev->name, &pip6->daddr, daddr, &pip6->saddr, n->ha);

	if (p) {
		dev_queue_xmit(reply);
	} else {
		skb_reset_mac_header(reply);
		__skb_pull(reply, skb_network_offset(reply));
		reply->ip_summed = CHECKSUM_UNNECESSARY;
		reply->pkt_type = PACKET_HOST;

		netif_rx_ni(reply);
	}
}

static int br_chk_addr_ip6(struct net_device *dev,
			   struct netdev_nested_priv *priv)
{
	struct in6_addr *addr = (struct in6_addr *)priv->data;

	if (ipv6_chk_addr(dev_net(dev), addr, dev, 0))
		return 1;

	return 0;
}

static bool br_is_local_ip6(struct net_device *dev, struct in6_addr *addr)

{
	struct netdev_nested_priv priv = {
		.data = (void *)addr,
	};

	if (br_chk_addr_ip6(dev, &priv))
		return true;

	/* check if ip is configured on upper dev */
	if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip6, &priv))
		return true;

	return false;
}

void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
		       u16 vid, struct net_bridge_port *p, struct nd_msg *msg)
{
	struct net_device *dev = br->dev;
	struct net_device *vlandev = NULL;
	struct in6_addr *saddr, *daddr;
	struct ipv6hdr *iphdr;
	struct neighbour *n;

	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0;

	if (p && (p->flags & BR_NEIGH_SUPPRESS))
		return;

	if (msg->icmph.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT &&
	    !msg->icmph.icmp6_solicited) {
		/* prevent flooding to neigh suppress ports */
		BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
		return;
	}

	if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
		return;

	iphdr = ipv6_hdr(skb);
	saddr = &iphdr->saddr;
	daddr = &iphdr->daddr;

	if (ipv6_addr_any(saddr) || !ipv6_addr_cmp(saddr, daddr)) {
		/* prevent flooding to neigh suppress ports */
		BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
		return;
	}

	if (vid != 0) {
		/* build neigh table lookup on the vlan device */
		vlandev = __vlan_find_dev_deep_rcu(br->dev, skb->vlan_proto,
						   vid);
		if (!vlandev)
			return;
	} else {
		vlandev = dev;
	}

	if (br_is_local_ip6(vlandev, &msg->target)) {
		/* its our own ip, so don't proxy reply
		 * and don't forward to arp suppress ports
		 */
		BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
		return;
	}

	n = neigh_lookup(ipv6_stub->nd_tbl, &msg->target, vlandev);
	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) {
			bool replied = false;

			if (f->dst && (f->dst->flags & BR_NEIGH_SUPPRESS)) {
				if (vid != 0)
					br_nd_send(br, p, skb, n,
						   skb->vlan_proto,
						   skb_vlan_tag_get(skb), msg);
				else
					br_nd_send(br, p, skb, n, 0, 0, msg);
				replied = true;
			}

			/* If we have replied or as long as we know the
			 * mac, indicate to NEIGH_SUPPRESS ports that we
			 * have replied
			 */
			if (replied ||
			    br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED))
				BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
		}
		neigh_release(n);
	}
}
#endif
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
821f1b21 RP	2	/*
	3	* Handle bridge arp/nd proxy/suppress
	4	*
	5	* Copyright (C) 2017 Cumulus Networks
	6	* Copyright (c) 2017 Roopa Prabhu <[email protected]>
	7	*
	8	* Authors:
	9	* Roopa Prabhu <[email protected]>
821f1b21 RP	10	*/
	11
	12	#include <linux/kernel.h>
057658cb RP	13	#include <linux/netdevice.h>
	14	#include <linux/etherdevice.h>
	15	#include <linux/neighbour.h>
	16	#include <net/arp.h>
	17	#include <linux/if_vlan.h>
	18	#include <linux/inetdevice.h>
	19	#include <net/addrconf.h>
3616d08b	20	#include <net/ipv6_stubs.h>
ed842fae RP	21	#if IS_ENABLED(CONFIG_IPV6)
	22	#include <net/ip6_checksum.h>
	23	#endif
057658cb	24
821f1b21 RP	25	#include "br_private.h"
	26
	27	void br_recalculate_neigh_suppress_enabled(struct net_bridge *br)
	28	{
	29	struct net_bridge_port *p;
	30	bool neigh_suppress = false;
	31
	32	list_for_each_entry(p, &br->port_list, list) {
	33	if (p->flags & BR_NEIGH_SUPPRESS) {
	34	neigh_suppress = true;
	35	break;
	36	}
	37	}
	38
c69c2cd4	39	br_opt_toggle(br, BROPT_NEIGH_SUPPRESS_ENABLED, neigh_suppress);
821f1b21	40	}
057658cb RP	41
	42	#if IS_ENABLED(CONFIG_INET)
	43	static void br_arp_send(struct net_bridge br, struct net_bridge_port p,
	44	struct net_device *dev, __be32 dest_ip, __be32 src_ip,
	45	const unsigned char *dest_hw,
	46	const unsigned char *src_hw,
	47	const unsigned char *target_hw,
	48	__be16 vlan_proto, u16 vlan_tci)
	49	{
	50	struct net_bridge_vlan_group *vg;
	51	struct sk_buff *skb;
	52	u16 pvid;
	53
	54	netdev_dbg(dev, "arp send dev %s dst %pI4 dst_hw %pM src %pI4 src_hw %pM\n",
	55	dev->name, &dest_ip, dest_hw, &src_ip, src_hw);
	56
	57	if (!vlan_tci) {
	58	arp_send(ARPOP_REPLY, ETH_P_ARP, dest_ip, dev, src_ip,
	59	dest_hw, src_hw, target_hw);
	60	return;
	61	}
	62
	63	skb = arp_create(ARPOP_REPLY, ETH_P_ARP, dest_ip, dev, src_ip,
	64	dest_hw, src_hw, target_hw);
	65	if (!skb)
	66	return;
	67
	68	if (p)
	69	vg = nbp_vlan_group_rcu(p);
	70	else
	71	vg = br_vlan_group_rcu(br);
	72	pvid = br_get_pvid(vg);
	73	if (pvid == (vlan_tci & VLAN_VID_MASK))
	74	vlan_tci = 0;
	75
	76	if (vlan_tci)
	77	__vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
	78
	79	if (p) {
	80	arp_xmit(skb);
	81	} else {
	82	skb_reset_mac_header(skb);
	83	__skb_pull(skb, skb_network_offset(skb));
	84	skb->ip_summed = CHECKSUM_UNNECESSARY;
	85	skb->pkt_type = PACKET_HOST;
	86
	87	netif_rx_ni(skb);
	88	}
	89	}
	90
eff74233 TY	91	static int br_chk_addr_ip(struct net_device *dev,
eff74233 TY	92	struct netdev_nested_priv *priv)
057658cb	93	{
eff74233	94	__be32 ip = (__be32 )priv->data;
057658cb RP	95	struct in_device *in_dev;
	96	__be32 addr = 0;
	97
	98	in_dev = __in_dev_get_rcu(dev);
	99	if (in_dev)
	100	addr = inet_confirm_addr(dev_net(dev), in_dev, 0, ip,
	101	RT_SCOPE_HOST);
	102
	103	if (addr == ip)
	104	return 1;
	105
	106	return 0;
	107	}
	108
	109	static bool br_is_local_ip(struct net_device *dev, __be32 ip)
	110	{
eff74233 TY	111	struct netdev_nested_priv priv = {
	112	.data = (void *)&ip,
	113	};
	114
	115	if (br_chk_addr_ip(dev, &priv))
057658cb RP	116	return true;
	117
	118	/* check if ip is configured on upper dev */
eff74233	119	if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip, &priv))
057658cb RP	120	return true;
	121
	122	return false;
	123	}
	124
	125	void br_do_proxy_suppress_arp(struct sk_buff skb, struct net_bridge br,
	126	u16 vid, struct net_bridge_port *p)
	127	{
	128	struct net_device *dev = br->dev;
	129	struct net_device *vlandev = dev;
	130	struct neighbour *n;
	131	struct arphdr *parp;
	132	u8 arpptr, sha;
	133	__be32 sip, tip;
	134
f12064d1	135	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0;
057658cb RP	136
	137	if ((dev->flags & IFF_NOARP) \|\|
	138	!pskb_may_pull(skb, arp_hdr_len(dev)))
	139	return;
	140
	141	parp = arp_hdr(skb);
	142
	143	if (parp->ar_pro != htons(ETH_P_IP) \|\|
	144	parp->ar_hln != dev->addr_len \|\|
	145	parp->ar_pln != 4)
	146	return;
	147
	148	arpptr = (u8 *)parp + sizeof(struct arphdr);
	149	sha = arpptr;
	150	arpptr += dev->addr_len; /* sha */
	151	memcpy(&sip, arpptr, sizeof(sip));
	152	arpptr += sizeof(sip);
	153	arpptr += dev->addr_len; /* tha */
	154	memcpy(&tip, arpptr, sizeof(tip));
	155
	156	if (ipv4_is_loopback(tip) \|\|
	157	ipv4_is_multicast(tip))
	158	return;
	159
c69c2cd4	160	if (br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) {
057658cb RP	161	if (p && (p->flags & BR_NEIGH_SUPPRESS))
	162	return;
	163	if (ipv4_is_zeronet(sip) \|\| sip == tip) {
	164	/* prevent flooding to neigh suppress ports */
f12064d1	165	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
057658cb RP	166	return;
	167	}
	168	}
	169
	170	if (parp->ar_op != htons(ARPOP_REQUEST))
	171	return;
	172
	173	if (vid != 0) {
	174	vlandev = __vlan_find_dev_deep_rcu(br->dev, skb->vlan_proto,
	175	vid);
	176	if (!vlandev)
	177	return;
	178	}
	179
c69c2cd4 NA	180	if (br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) &&
c69c2cd4 NA	181	br_is_local_ip(vlandev, tip)) {
057658cb RP	182	/* its our local ip, so don't proxy reply
	183	* and don't forward to neigh suppress ports
	184	*/
f12064d1	185	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
057658cb RP	186	return;
	187	}
	188
	189	n = neigh_lookup(&arp_tbl, &tip, vlandev);
	190	if (n) {
	191	struct net_bridge_fdb_entry *f;
	192
	193	if (!(n->nud_state & NUD_VALID)) {
	194	neigh_release(n);
	195	return;
	196	}
	197
	198	f = br_fdb_find_rcu(br, n->ha, vid);
	199	if (f) {
	200	bool replied = false;
	201
	202	if ((p && (p->flags & BR_PROXYARP)) \|\|
	203	(f->dst && (f->dst->flags & (BR_PROXYARP_WIFI \|
	204	BR_NEIGH_SUPPRESS)))) {
	205	if (!vid)
	206	br_arp_send(br, p, skb->dev, sip, tip,
	207	sha, n->ha, sha, 0, 0);
	208	else
	209	br_arp_send(br, p, skb->dev, sip, tip,
	210	sha, n->ha, sha,
	211	skb->vlan_proto,
	212	skb_vlan_tag_get(skb));
	213	replied = true;
	214	}
	215
	216	/* If we have replied or as long as we know the
	217	* mac, indicate to arp replied
	218	*/
c69c2cd4 NA	219	if (replied \|\|
c69c2cd4 NA	220	br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED))
f12064d1	221	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
057658cb RP	222	}
	223
	224	neigh_release(n);
	225	}
	226	}
	227	#endif
ed842fae RP	228
	229	#if IS_ENABLED(CONFIG_IPV6)
	230	struct nd_msg br_is_nd_neigh_msg(struct sk_buff skb, struct nd_msg *msg)
	231	{
	232	struct nd_msg *m;
	233
	234	m = skb_header_pointer(skb, skb_network_offset(skb) +
	235	sizeof(struct ipv6hdr), sizeof(*msg), msg);
	236	if (!m)
	237	return NULL;
	238
	239	if (m->icmph.icmp6_code != 0 \|\|
	240	(m->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION &&
	241	m->icmph.icmp6_type != NDISC_NEIGHBOUR_ADVERTISEMENT))
	242	return NULL;
	243
	244	return m;
	245	}
	246
	247	static void br_nd_send(struct net_bridge br, struct net_bridge_port p,
	248	struct sk_buff request, struct neighbour n,
	249	__be16 vlan_proto, u16 vlan_tci, struct nd_msg *ns)
	250	{
	251	struct net_device *dev = request->dev;
	252	struct net_bridge_vlan_group *vg;
	253	struct sk_buff *reply;
	254	struct nd_msg *na;
	255	struct ipv6hdr *pip6;
	256	int na_olen = 8; /* opt hdr + ETH_ALEN for target */
	257	int ns_olen;
	258	int i, len;
	259	u8 *daddr;
	260	u16 pvid;
	261
	262	if (!dev)
	263	return;
	264
	265	len = LL_RESERVED_SPACE(dev) + sizeof(struct ipv6hdr) +
	266	sizeof(*na) + na_olen + dev->needed_tailroom;
	267
	268	reply = alloc_skb(len, GFP_ATOMIC);
	269	if (!reply)
	270	return;
	271
	272	reply->protocol = htons(ETH_P_IPV6);
	273	reply->dev = dev;
	274	skb_reserve(reply, LL_RESERVED_SPACE(dev));
	275	skb_push(reply, sizeof(struct ethhdr));
	276	skb_set_mac_header(reply, 0);
	277
	278	daddr = eth_hdr(request)->h_source;
	279
	280	/* Do we need option processing ? */
	281	ns_olen = request->len - (skb_network_offset(request) +
	282	sizeof(struct ipv6hdr)) - sizeof(*ns);
	283	for (i = 0; i < ns_olen - 1; i += (ns->opt[i + 1] << 3)) {
53fc6852 IS	284	if (!ns->opt[i + 1]) {
	285	kfree_skb(reply);
	286	return;
	287	}
ed842fae RP	288	if (ns->opt[i] == ND_OPT_SOURCE_LL_ADDR) {
	289	daddr = ns->opt + i + sizeof(struct nd_opt_hdr);
	290	break;
	291	}
	292	}
	293
	294	/* Ethernet header */
	295	ether_addr_copy(eth_hdr(reply)->h_dest, daddr);
	296	ether_addr_copy(eth_hdr(reply)->h_source, n->ha);
	297	eth_hdr(reply)->h_proto = htons(ETH_P_IPV6);
	298	reply->protocol = htons(ETH_P_IPV6);
	299
	300	skb_pull(reply, sizeof(struct ethhdr));
	301	skb_set_network_header(reply, 0);
	302	skb_put(reply, sizeof(struct ipv6hdr));
	303
	304	/* IPv6 header */
	305	pip6 = ipv6_hdr(reply);
	306	memset(pip6, 0, sizeof(struct ipv6hdr));
	307	pip6->version = 6;
	308	pip6->priority = ipv6_hdr(request)->priority;
	309	pip6->nexthdr = IPPROTO_ICMPV6;
	310	pip6->hop_limit = 255;
	311	pip6->daddr = ipv6_hdr(request)->saddr;
	312	pip6->saddr = (struct in6_addr )n->primary_key;
	313
	314	skb_pull(reply, sizeof(struct ipv6hdr));
	315	skb_set_transport_header(reply, 0);
	316
	317	na = (struct nd_msg )skb_put(reply, sizeof(na) + na_olen);
	318
	319	/* Neighbor Advertisement */
	320	memset(na, 0, sizeof(*na) + na_olen);
	321	na->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
7aca011f	322	na->icmph.icmp6_router = (n->flags & NTF_ROUTER) ? 1 : 0;
ed842fae RP	323	na->icmph.icmp6_override = 1;
	324	na->icmph.icmp6_solicited = 1;
	325	na->target = ns->target;
	326	ether_addr_copy(&na->opt[2], n->ha);
	327	na->opt[0] = ND_OPT_TARGET_LL_ADDR;
	328	na->opt[1] = na_olen >> 3;
	329
	330	na->icmph.icmp6_cksum = csum_ipv6_magic(&pip6->saddr,
	331	&pip6->daddr,
	332	sizeof(*na) + na_olen,
	333	IPPROTO_ICMPV6,
	334	csum_partial(na, sizeof(*na) + na_olen, 0));
	335
	336	pip6->payload_len = htons(sizeof(*na) + na_olen);
	337
	338	skb_push(reply, sizeof(struct ipv6hdr));
	339	skb_push(reply, sizeof(struct ethhdr));
	340
	341	reply->ip_summed = CHECKSUM_UNNECESSARY;
	342
	343	if (p)
	344	vg = nbp_vlan_group_rcu(p);
	345	else
	346	vg = br_vlan_group_rcu(br);
	347	pvid = br_get_pvid(vg);
	348	if (pvid == (vlan_tci & VLAN_VID_MASK))
	349	vlan_tci = 0;
	350
	351	if (vlan_tci)
	352	__vlan_hwaccel_put_tag(reply, vlan_proto, vlan_tci);
	353
	354	netdev_dbg(dev, "nd send dev %s dst %pI6 dst_hw %pM src %pI6 src_hw %pM\n",
	355	dev->name, &pip6->daddr, daddr, &pip6->saddr, n->ha);
	356
	357	if (p) {
	358	dev_queue_xmit(reply);
	359	} else {
	360	skb_reset_mac_header(reply);
	361	__skb_pull(reply, skb_network_offset(reply));
	362	reply->ip_summed = CHECKSUM_UNNECESSARY;
	363	reply->pkt_type = PACKET_HOST;
	364
	365	netif_rx_ni(reply);
	366	}
	367	}
	368
eff74233 TY	369	static int br_chk_addr_ip6(struct net_device *dev,
eff74233 TY	370	struct netdev_nested_priv *priv)
ed842fae	371	{
eff74233	372	struct in6_addr addr = (struct in6_addr )priv->data;
ed842fae RP	373
	374	if (ipv6_chk_addr(dev_net(dev), addr, dev, 0))
	375	return 1;
	376
	377	return 0;
	378	}
	379
	380	static bool br_is_local_ip6(struct net_device dev, struct in6_addr addr)
	381
	382	{
eff74233 TY	383	struct netdev_nested_priv priv = {
	384	.data = (void *)addr,
	385	};
	386
	387	if (br_chk_addr_ip6(dev, &priv))
ed842fae RP	388	return true;
	389
	390	/* check if ip is configured on upper dev */
eff74233	391	if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip6, &priv))
ed842fae RP	392	return true;
	393
	394	return false;
	395	}
	396
	397	void br_do_suppress_nd(struct sk_buff skb, struct net_bridge br,
	398	u16 vid, struct net_bridge_port p, struct nd_msg msg)
	399	{
	400	struct net_device *dev = br->dev;
	401	struct net_device *vlandev = NULL;
	402	struct in6_addr saddr, daddr;
	403	struct ipv6hdr *iphdr;
	404	struct neighbour *n;
	405
f12064d1	406	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0;
ed842fae RP	407
	408	if (p && (p->flags & BR_NEIGH_SUPPRESS))
	409	return;
	410
	411	if (msg->icmph.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT &&
	412	!msg->icmph.icmp6_solicited) {
	413	/* prevent flooding to neigh suppress ports */
f12064d1	414	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
ed842fae RP	415	return;
	416	}
	417
	418	if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
	419	return;
	420
	421	iphdr = ipv6_hdr(skb);
	422	saddr = &iphdr->saddr;
	423	daddr = &iphdr->daddr;
	424
	425	if (ipv6_addr_any(saddr) \|\| !ipv6_addr_cmp(saddr, daddr)) {
	426	/* prevent flooding to neigh suppress ports */
f12064d1	427	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
ed842fae RP	428	return;
	429	}
	430
	431	if (vid != 0) {
	432	/* build neigh table lookup on the vlan device */
	433	vlandev = __vlan_find_dev_deep_rcu(br->dev, skb->vlan_proto,
	434	vid);
	435	if (!vlandev)
	436	return;
	437	} else {
	438	vlandev = dev;
	439	}
	440
	441	if (br_is_local_ip6(vlandev, &msg->target)) {
	442	/* its our own ip, so don't proxy reply
	443	* and don't forward to arp suppress ports
	444	*/
f12064d1	445	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
ed842fae RP	446	return;
	447	}
	448
	449	n = neigh_lookup(ipv6_stub->nd_tbl, &msg->target, vlandev);
	450	if (n) {
	451	struct net_bridge_fdb_entry *f;
	452
	453	if (!(n->nud_state & NUD_VALID)) {
	454	neigh_release(n);
	455	return;
	456	}
	457
	458	f = br_fdb_find_rcu(br, n->ha, vid);
	459	if (f) {
	460	bool replied = false;
	461
	462	if (f->dst && (f->dst->flags & BR_NEIGH_SUPPRESS)) {
	463	if (vid != 0)
	464	br_nd_send(br, p, skb, n,
	465	skb->vlan_proto,
	466	skb_vlan_tag_get(skb), msg);
	467	else
	468	br_nd_send(br, p, skb, n, 0, 0, msg);
	469	replied = true;
	470	}
	471
	472	/* If we have replied or as long as we know the
	473	* mac, indicate to NEIGH_SUPPRESS ports that we
	474	* have replied
	475	*/
c69c2cd4 NA	476	if (replied \|\|
c69c2cd4 NA	477	br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED))
f12064d1	478	BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1;
ed842fae RP	479	}
	480	neigh_release(n);
	481	}
	482	}
	483	#endif