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

/*
 *  Handle bridge arp/nd proxy/suppress
 *
 *  Copyright (C) 2017 Cumulus Networks
 *  Copyright (c) 2017 Roopa Prabhu <roopa@cumulusnetworks.com>
 *
 *  Authors:
 *	Roopa Prabhu <roopa@cumulusnetworks.com>
 *
 *  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/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, void *data)
{
	__be32 ip = *(__be32 *)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)
{
	if (br_chk_addr_ip(dev, &ip))
		return true;

	/* check if ip is configured on upper dev */
	if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip, &ip))
		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 = 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_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 = true;
			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 = true;
		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 = true;
		}

		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] == 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, void *data)
{
	struct in6_addr *addr = (struct in6_addr *)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)

{
	if (br_chk_addr_ip6(dev, addr))
		return true;

	/* check if ip is configured on upper dev */
	if (netdev_walk_all_upper_dev_rcu(dev, br_chk_addr_ip6, addr))
		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 = false;

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