br_multicast.c 38.3 KB
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/*
 * Bridge multicast support.
 *
 * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * 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/err.h>
#include <linux/if_ether.h>
#include <linux/igmp.h>
#include <linux/jhash.h>
#include <linux/kernel.h>
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#include <linux/log2.h>
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#include <linux/netdevice.h>
#include <linux/netfilter_bridge.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <net/ip.h>
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#if IS_ENABLED(CONFIG_IPV6)
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#include <net/ipv6.h>
#include <net/mld.h>
#include <net/addrconf.h>
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#include <net/ip6_checksum.h>
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#endif
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#include "br_private.h"

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#define mlock_dereference(X, br) \
	rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))

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#if IS_ENABLED(CONFIG_IPV6)
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static inline int ipv6_is_transient_multicast(const struct in6_addr *addr)
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{
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	if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr))
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		return 1;
	return 0;
}
#endif

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static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
{
	if (a->proto != b->proto)
		return 0;
	switch (a->proto) {
	case htons(ETH_P_IP):
		return a->u.ip4 == b->u.ip4;
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#if IS_ENABLED(CONFIG_IPV6)
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	case htons(ETH_P_IPV6):
		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
#endif
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	}
	return 0;
}

static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
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{
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	return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
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}

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#if IS_ENABLED(CONFIG_IPV6)
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static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
				const struct in6_addr *ip)
{
	return jhash2((__force u32 *)ip->s6_addr32, 4, mdb->secret) & (mdb->max - 1);
}
#endif

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static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
			     struct br_ip *ip)
{
	switch (ip->proto) {
	case htons(ETH_P_IP):
		return __br_ip4_hash(mdb, ip->u.ip4);
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#if IS_ENABLED(CONFIG_IPV6)
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	case htons(ETH_P_IPV6):
		return __br_ip6_hash(mdb, &ip->u.ip6);
#endif
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	}
	return 0;
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}

static struct net_bridge_mdb_entry *__br_mdb_ip_get(
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	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
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{
	struct net_bridge_mdb_entry *mp;
	struct hlist_node *p;

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	hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
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		if (br_ip_equal(&mp->addr, dst))
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			return mp;
	}

	return NULL;
}

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static struct net_bridge_mdb_entry *br_mdb_ip_get(
	struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
{
	if (!mdb)
		return NULL;

	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
}

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static struct net_bridge_mdb_entry *br_mdb_ip4_get(
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	struct net_bridge_mdb_htable *mdb, __be32 dst)
{
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	struct br_ip br_dst;

	br_dst.u.ip4 = dst;
	br_dst.proto = htons(ETH_P_IP);
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	return br_mdb_ip_get(mdb, &br_dst);
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}

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#if IS_ENABLED(CONFIG_IPV6)
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static struct net_bridge_mdb_entry *br_mdb_ip6_get(
	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
{
	struct br_ip br_dst;
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	br_dst.u.ip6 = *dst;
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	br_dst.proto = htons(ETH_P_IPV6);

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	return br_mdb_ip_get(mdb, &br_dst);
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}
#endif

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struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
					struct sk_buff *skb)
{
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	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
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	struct br_ip ip;

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	if (br->multicast_disabled)
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		return NULL;

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	if (BR_INPUT_SKB_CB(skb)->igmp)
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		return NULL;

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	ip.proto = skb->protocol;

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	switch (skb->protocol) {
	case htons(ETH_P_IP):
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		ip.u.ip4 = ip_hdr(skb)->daddr;
		break;
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#if IS_ENABLED(CONFIG_IPV6)
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	case htons(ETH_P_IPV6):
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		ip.u.ip6 = ipv6_hdr(skb)->daddr;
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		break;
#endif
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	default:
		return NULL;
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	}

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	return br_mdb_ip_get(mdb, &ip);
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}

static void br_mdb_free(struct rcu_head *head)
{
	struct net_bridge_mdb_htable *mdb =
		container_of(head, struct net_bridge_mdb_htable, rcu);
	struct net_bridge_mdb_htable *old = mdb->old;

	mdb->old = NULL;
	kfree(old->mhash);
	kfree(old);
}

static int br_mdb_copy(struct net_bridge_mdb_htable *new,
		       struct net_bridge_mdb_htable *old,
		       int elasticity)
{
	struct net_bridge_mdb_entry *mp;
	struct hlist_node *p;
	int maxlen;
	int len;
	int i;

	for (i = 0; i < old->max; i++)
		hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
			hlist_add_head(&mp->hlist[new->ver],
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				       &new->mhash[br_ip_hash(new, &mp->addr)]);
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	if (!elasticity)
		return 0;

	maxlen = 0;
	for (i = 0; i < new->max; i++) {
		len = 0;
		hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
			len++;
		if (len > maxlen)
			maxlen = len;
	}

	return maxlen > elasticity ? -EINVAL : 0;
}

static void br_multicast_free_pg(struct rcu_head *head)
{
	struct net_bridge_port_group *p =
		container_of(head, struct net_bridge_port_group, rcu);

	kfree(p);
}

static void br_multicast_free_group(struct rcu_head *head)
{
	struct net_bridge_mdb_entry *mp =
		container_of(head, struct net_bridge_mdb_entry, rcu);

	kfree(mp);
}

static void br_multicast_group_expired(unsigned long data)
{
	struct net_bridge_mdb_entry *mp = (void *)data;
	struct net_bridge *br = mp->br;
	struct net_bridge_mdb_htable *mdb;

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) || timer_pending(&mp->timer))
		goto out;

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	mp->mglist = false;
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	if (mp->ports)
		goto out;

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	mdb = mlock_dereference(br->mdb, br);

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	hlist_del_rcu(&mp->hlist[mdb->ver]);
	mdb->size--;

	call_rcu_bh(&mp->rcu, br_multicast_free_group);

out:
	spin_unlock(&br->multicast_lock);
}

static void br_multicast_del_pg(struct net_bridge *br,
				struct net_bridge_port_group *pg)
{
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	struct net_bridge_mdb_htable *mdb;
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	struct net_bridge_mdb_entry *mp;
	struct net_bridge_port_group *p;
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	struct net_bridge_port_group __rcu **pp;

	mdb = mlock_dereference(br->mdb, br);
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	mp = br_mdb_ip_get(mdb, &pg->addr);
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	if (WARN_ON(!mp))
		return;

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	for (pp = &mp->ports;
	     (p = mlock_dereference(*pp, br)) != NULL;
	     pp = &p->next) {
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		if (p != pg)
			continue;

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		rcu_assign_pointer(*pp, p->next);
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		hlist_del_init(&p->mglist);
		del_timer(&p->timer);
		call_rcu_bh(&p->rcu, br_multicast_free_pg);

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		if (!mp->ports && !mp->mglist &&
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		    netif_running(br->dev))
			mod_timer(&mp->timer, jiffies);

		return;
	}

	WARN_ON(1);
}

static void br_multicast_port_group_expired(unsigned long data)
{
	struct net_bridge_port_group *pg = (void *)data;
	struct net_bridge *br = pg->port->br;

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
	    hlist_unhashed(&pg->mglist))
		goto out;

	br_multicast_del_pg(br, pg);

out:
	spin_unlock(&br->multicast_lock);
}

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static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
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			 int elasticity)
{
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	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
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	struct net_bridge_mdb_htable *mdb;
	int err;

	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
	if (!mdb)
		return -ENOMEM;

	mdb->max = max;
	mdb->old = old;

	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
	if (!mdb->mhash) {
		kfree(mdb);
		return -ENOMEM;
	}

	mdb->size = old ? old->size : 0;
	mdb->ver = old ? old->ver ^ 1 : 0;

	if (!old || elasticity)
		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
	else
		mdb->secret = old->secret;

	if (!old)
		goto out;

	err = br_mdb_copy(mdb, old, elasticity);
	if (err) {
		kfree(mdb->mhash);
		kfree(mdb);
		return err;
	}

	call_rcu_bh(&mdb->rcu, br_mdb_free);

out:
	rcu_assign_pointer(*mdbp, mdb);

	return 0;
}

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static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
						    __be32 group)
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{
	struct sk_buff *skb;
	struct igmphdr *ih;
	struct ethhdr *eth;
	struct iphdr *iph;

	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
						 sizeof(*ih) + 4);
	if (!skb)
		goto out;

	skb->protocol = htons(ETH_P_IP);

	skb_reset_mac_header(skb);
	eth = eth_hdr(skb);

	memcpy(eth->h_source, br->dev->dev_addr, 6);
	eth->h_dest[0] = 1;
	eth->h_dest[1] = 0;
	eth->h_dest[2] = 0x5e;
	eth->h_dest[3] = 0;
	eth->h_dest[4] = 0;
	eth->h_dest[5] = 1;
	eth->h_proto = htons(ETH_P_IP);
	skb_put(skb, sizeof(*eth));

	skb_set_network_header(skb, skb->len);
	iph = ip_hdr(skb);

	iph->version = 4;
	iph->ihl = 6;
	iph->tos = 0xc0;
	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
	iph->id = 0;
	iph->frag_off = htons(IP_DF);
	iph->ttl = 1;
	iph->protocol = IPPROTO_IGMP;
	iph->saddr = 0;
	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
	((u8 *)&iph[1])[0] = IPOPT_RA;
	((u8 *)&iph[1])[1] = 4;
	((u8 *)&iph[1])[2] = 0;
	((u8 *)&iph[1])[3] = 0;
	ip_send_check(iph);
	skb_put(skb, 24);

	skb_set_transport_header(skb, skb->len);
	ih = igmp_hdr(skb);
	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
	ih->code = (group ? br->multicast_last_member_interval :
			    br->multicast_query_response_interval) /
		   (HZ / IGMP_TIMER_SCALE);
	ih->group = group;
	ih->csum = 0;
	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
	skb_put(skb, sizeof(*ih));

	__skb_pull(skb, sizeof(*eth));

out:
	return skb;
}

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#if IS_ENABLED(CONFIG_IPV6)
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static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
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						    const struct in6_addr *group)
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{
	struct sk_buff *skb;
	struct ipv6hdr *ip6h;
	struct mld_msg *mldq;
	struct ethhdr *eth;
	u8 *hopopt;
	unsigned long interval;

	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
						 8 + sizeof(*mldq));
	if (!skb)
		goto out;

	skb->protocol = htons(ETH_P_IPV6);

	/* Ethernet header */
	skb_reset_mac_header(skb);
	eth = eth_hdr(skb);

	memcpy(eth->h_source, br->dev->dev_addr, 6);
	eth->h_proto = htons(ETH_P_IPV6);
	skb_put(skb, sizeof(*eth));

	/* IPv6 header + HbH option */
	skb_set_network_header(skb, skb->len);
	ip6h = ipv6_hdr(skb);

	*(__force __be32 *)ip6h = htonl(0x60000000);
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	ip6h->payload_len = htons(8 + sizeof(*mldq));
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	ip6h->nexthdr = IPPROTO_HOPOPTS;
	ip6h->hop_limit = 1;
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	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
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	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
			       &ip6h->saddr)) {
		kfree_skb(skb);
		return NULL;
	}
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	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
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	hopopt = (u8 *)(ip6h + 1);
	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
	hopopt[1] = 0;				/* length of HbH */
	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
	hopopt[3] = 2;				/* Length of RA Option */
	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
	hopopt[5] = 0;
	hopopt[6] = IPV6_TLV_PAD0;		/* Pad0 */
	hopopt[7] = IPV6_TLV_PAD0;		/* Pad0 */

	skb_put(skb, sizeof(*ip6h) + 8);

	/* ICMPv6 */
	skb_set_transport_header(skb, skb->len);
	mldq = (struct mld_msg *) icmp6_hdr(skb);

	interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
					  br->multicast_query_response_interval;

	mldq->mld_type = ICMPV6_MGM_QUERY;
	mldq->mld_code = 0;
	mldq->mld_cksum = 0;
	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
	mldq->mld_reserved = 0;
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	mldq->mld_mca = *group;
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	/* checksum */
	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
					  sizeof(*mldq), IPPROTO_ICMPV6,
					  csum_partial(mldq,
						       sizeof(*mldq), 0));
	skb_put(skb, sizeof(*mldq));

	__skb_pull(skb, sizeof(*eth));

out:
	return skb;
}
#endif

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static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
						struct br_ip *addr)
{
	switch (addr->proto) {
	case htons(ETH_P_IP):
		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
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#if IS_ENABLED(CONFIG_IPV6)
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	case htons(ETH_P_IPV6):
		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
#endif
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	}
	return NULL;
}

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static struct net_bridge_mdb_entry *br_multicast_get_group(
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	struct net_bridge *br, struct net_bridge_port *port,
	struct br_ip *group, int hash)
511
{
512
	struct net_bridge_mdb_htable *mdb;
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	struct net_bridge_mdb_entry *mp;
	struct hlist_node *p;
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	unsigned int count = 0;
	unsigned int max;
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	int elasticity;
	int err;

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	mdb = rcu_dereference_protected(br->mdb, 1);
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	hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
		count++;
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		if (unlikely(br_ip_equal(group, &mp->addr)))
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			return mp;
	}

	elasticity = 0;
	max = mdb->max;

	if (unlikely(count > br->hash_elasticity && count)) {
		if (net_ratelimit())
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			br_info(br, "Multicast hash table "
				"chain limit reached: %s\n",
				port ? port->dev->name : br->dev->name);
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		elasticity = br->hash_elasticity;
	}

	if (mdb->size >= max) {
		max *= 2;
		if (unlikely(max >= br->hash_max)) {
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			br_warn(br, "Multicast hash table maximum "
				"reached, disabling snooping: %s, %d\n",
				port ? port->dev->name : br->dev->name, max);
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			err = -E2BIG;
disable:
			br->multicast_disabled = 1;
			goto err;
		}
	}

	if (max > mdb->max || elasticity) {
		if (mdb->old) {
			if (net_ratelimit())
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				br_info(br, "Multicast hash table "
					"on fire: %s\n",
					port ? port->dev->name : br->dev->name);
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			err = -EEXIST;
			goto err;
		}

		err = br_mdb_rehash(&br->mdb, max, elasticity);
		if (err) {
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			br_warn(br, "Cannot rehash multicast "
				"hash table, disabling snooping: %s, %d, %d\n",
				port ? port->dev->name : br->dev->name,
				mdb->size, err);
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			goto disable;
		}

		err = -EAGAIN;
		goto err;
	}

	return NULL;

err:
	mp = ERR_PTR(err);
	return mp;
}

static struct net_bridge_mdb_entry *br_multicast_new_group(
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	struct net_bridge *br, struct net_bridge_port *port,
	struct br_ip *group)
585
{
586
	struct net_bridge_mdb_htable *mdb;
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	struct net_bridge_mdb_entry *mp;
	int hash;
589
	int err;
590

591
	mdb = rcu_dereference_protected(br->mdb, 1);
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	if (!mdb) {
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		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
		if (err)
			return ERR_PTR(err);
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		goto rehash;
	}

	hash = br_ip_hash(mdb, group);
	mp = br_multicast_get_group(br, port, group, hash);
	switch (PTR_ERR(mp)) {
	case 0:
		break;

	case -EAGAIN:
rehash:
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		mdb = rcu_dereference_protected(br->mdb, 1);
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		hash = br_ip_hash(mdb, group);
		break;

	default:
		goto out;
	}

	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
	if (unlikely(!mp))
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		return ERR_PTR(-ENOMEM);
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	mp->br = br;
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	mp->addr = *group;
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	setup_timer(&mp->timer, br_multicast_group_expired,
		    (unsigned long)mp);

	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
	mdb->size++;

out:
	return mp;
}

static int br_multicast_add_group(struct net_bridge *br,
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				  struct net_bridge_port *port,
				  struct br_ip *group)
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{
	struct net_bridge_mdb_entry *mp;
	struct net_bridge_port_group *p;
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	struct net_bridge_port_group __rcu **pp;
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	unsigned long now = jiffies;
	int err;

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) ||
	    (port && port->state == BR_STATE_DISABLED))
		goto out;

	mp = br_multicast_new_group(br, port, group);
	err = PTR_ERR(mp);
648
	if (IS_ERR(mp))
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		goto err;

	if (!port) {
652
		mp->mglist = true;
653 654 655 656
		mod_timer(&mp->timer, now + br->multicast_membership_interval);
		goto out;
	}

657 658 659
	for (pp = &mp->ports;
	     (p = mlock_dereference(*pp, br)) != NULL;
	     pp = &p->next) {
660 661 662 663 664 665 666 667 668 669 670
		if (p->port == port)
			goto found;
		if ((unsigned long)p->port < (unsigned long)port)
			break;
	}

	p = kzalloc(sizeof(*p), GFP_ATOMIC);
	err = -ENOMEM;
	if (unlikely(!p))
		goto err;

671
	p->addr = *group;
672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689
	p->port = port;
	p->next = *pp;
	hlist_add_head(&p->mglist, &port->mglist);
	setup_timer(&p->timer, br_multicast_port_group_expired,
		    (unsigned long)p);

	rcu_assign_pointer(*pp, p);

found:
	mod_timer(&p->timer, now + br->multicast_membership_interval);
out:
	err = 0;

err:
	spin_unlock(&br->multicast_lock);
	return err;
}

690 691 692 693 694 695 696 697 698 699 700 701 702 703 704
static int br_ip4_multicast_add_group(struct net_bridge *br,
				      struct net_bridge_port *port,
				      __be32 group)
{
	struct br_ip br_group;

	if (ipv4_is_local_multicast(group))
		return 0;

	br_group.u.ip4 = group;
	br_group.proto = htons(ETH_P_IP);

	return br_multicast_add_group(br, port, &br_group);
}

E
Eric Dumazet 已提交
705
#if IS_ENABLED(CONFIG_IPV6)
706 707 708 709 710 711
static int br_ip6_multicast_add_group(struct net_bridge *br,
				      struct net_bridge_port *port,
				      const struct in6_addr *group)
{
	struct br_ip br_group;

712
	if (!ipv6_is_transient_multicast(group))
713 714
		return 0;

A
Alexey Dobriyan 已提交
715
	br_group.u.ip6 = *group;
716
	br_group.proto = htons(ETH_P_IPV6);
717 718 719 720 721

	return br_multicast_add_group(br, port, &br_group);
}
#endif

722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742
static void br_multicast_router_expired(unsigned long data)
{
	struct net_bridge_port *port = (void *)data;
	struct net_bridge *br = port->br;

	spin_lock(&br->multicast_lock);
	if (port->multicast_router != 1 ||
	    timer_pending(&port->multicast_router_timer) ||
	    hlist_unhashed(&port->rlist))
		goto out;

	hlist_del_init_rcu(&port->rlist);

out:
	spin_unlock(&br->multicast_lock);
}

static void br_multicast_local_router_expired(unsigned long data)
{
}

743 744 745
static void __br_multicast_send_query(struct net_bridge *br,
				      struct net_bridge_port *port,
				      struct br_ip *ip)
746 747 748
{
	struct sk_buff *skb;

749
	skb = br_multicast_alloc_query(br, ip);
750
	if (!skb)
751
		return;
752 753 754 755

	if (port) {
		__skb_push(skb, sizeof(struct ethhdr));
		skb->dev = port->dev;
756
		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
757 758 759
			dev_queue_xmit);
	} else
		netif_rx(skb);
760 761 762 763 764 765 766 767 768 769 770 771
}

static void br_multicast_send_query(struct net_bridge *br,
				    struct net_bridge_port *port, u32 sent)
{
	unsigned long time;
	struct br_ip br_group;

	if (!netif_running(br->dev) || br->multicast_disabled ||
	    timer_pending(&br->multicast_querier_timer))
		return;

772 773
	memset(&br_group.u, 0, sizeof(br_group.u));

774
	br_group.proto = htons(ETH_P_IP);
775
	__br_multicast_send_query(br, port, &br_group);
776

E
Eric Dumazet 已提交
777
#if IS_ENABLED(CONFIG_IPV6)
778
	br_group.proto = htons(ETH_P_IPV6);
779
	__br_multicast_send_query(br, port, &br_group);
780
#endif
781 782 783 784 785 786 787 788 789 790 791 792 793 794 795

	time = jiffies;
	time += sent < br->multicast_startup_query_count ?
		br->multicast_startup_query_interval :
		br->multicast_query_interval;
	mod_timer(port ? &port->multicast_query_timer :
			 &br->multicast_query_timer, time);
}

static void br_multicast_port_query_expired(unsigned long data)
{
	struct net_bridge_port *port = (void *)data;
	struct net_bridge *br = port->br;

	spin_lock(&br->multicast_lock);
796 797
	if (port->state == BR_STATE_DISABLED ||
	    port->state == BR_STATE_BLOCKING)
798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825
		goto out;

	if (port->multicast_startup_queries_sent <
	    br->multicast_startup_query_count)
		port->multicast_startup_queries_sent++;

	br_multicast_send_query(port->br, port,
				port->multicast_startup_queries_sent);

out:
	spin_unlock(&br->multicast_lock);
}

void br_multicast_add_port(struct net_bridge_port *port)
{
	port->multicast_router = 1;

	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
		    (unsigned long)port);
	setup_timer(&port->multicast_query_timer,
		    br_multicast_port_query_expired, (unsigned long)port);
}

void br_multicast_del_port(struct net_bridge_port *port)
{
	del_timer_sync(&port->multicast_router_timer);
}

826 827 828 829 830 831 832 833 834
static void __br_multicast_enable_port(struct net_bridge_port *port)
{
	port->multicast_startup_queries_sent = 0;

	if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
	    del_timer(&port->multicast_query_timer))
		mod_timer(&port->multicast_query_timer, jiffies);
}

835 836 837 838 839 840 841 842
void br_multicast_enable_port(struct net_bridge_port *port)
{
	struct net_bridge *br = port->br;

	spin_lock(&br->multicast_lock);
	if (br->multicast_disabled || !netif_running(br->dev))
		goto out;

843
	__br_multicast_enable_port(port);
844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865

out:
	spin_unlock(&br->multicast_lock);
}

void br_multicast_disable_port(struct net_bridge_port *port)
{
	struct net_bridge *br = port->br;
	struct net_bridge_port_group *pg;
	struct hlist_node *p, *n;

	spin_lock(&br->multicast_lock);
	hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
		br_multicast_del_pg(br, pg);

	if (!hlist_unhashed(&port->rlist))
		hlist_del_init_rcu(&port->rlist);
	del_timer(&port->multicast_router_timer);
	del_timer(&port->multicast_query_timer);
	spin_unlock(&br->multicast_lock);
}

866 867 868
static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
					 struct net_bridge_port *port,
					 struct sk_buff *skb)
869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890
{
	struct igmpv3_report *ih;
	struct igmpv3_grec *grec;
	int i;
	int len;
	int num;
	int type;
	int err = 0;
	__be32 group;

	if (!pskb_may_pull(skb, sizeof(*ih)))
		return -EINVAL;

	ih = igmpv3_report_hdr(skb);
	num = ntohs(ih->ngrec);
	len = sizeof(*ih);

	for (i = 0; i < num; i++) {
		len += sizeof(*grec);
		if (!pskb_may_pull(skb, len))
			return -EINVAL;

H
Herbert Xu 已提交
891
		grec = (void *)(skb->data + len - sizeof(*grec));
892 893 894
		group = grec->grec_mca;
		type = grec->grec_type;

E
Eric Dumazet 已提交
895
		len += ntohs(grec->grec_nsrcs) * 4;
896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912
		if (!pskb_may_pull(skb, len))
			return -EINVAL;

		/* We treat this as an IGMPv2 report for now. */
		switch (type) {
		case IGMPV3_MODE_IS_INCLUDE:
		case IGMPV3_MODE_IS_EXCLUDE:
		case IGMPV3_CHANGE_TO_INCLUDE:
		case IGMPV3_CHANGE_TO_EXCLUDE:
		case IGMPV3_ALLOW_NEW_SOURCES:
		case IGMPV3_BLOCK_OLD_SOURCES:
			break;

		default:
			continue;
		}

913
		err = br_ip4_multicast_add_group(br, port, group);
914 915 916 917 918 919 920
		if (err)
			break;
	}

	return err;
}

E
Eric Dumazet 已提交
921
#if IS_ENABLED(CONFIG_IPV6)
922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944
static int br_ip6_multicast_mld2_report(struct net_bridge *br,
					struct net_bridge_port *port,
					struct sk_buff *skb)
{
	struct icmp6hdr *icmp6h;
	struct mld2_grec *grec;
	int i;
	int len;
	int num;
	int err = 0;

	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
		return -EINVAL;

	icmp6h = icmp6_hdr(skb);
	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
	len = sizeof(*icmp6h);

	for (i = 0; i < num; i++) {
		__be16 *nsrcs, _nsrcs;

		nsrcs = skb_header_pointer(skb,
					   len + offsetof(struct mld2_grec,
945
							  grec_nsrcs),
946 947 948 949 950 951
					   sizeof(_nsrcs), &_nsrcs);
		if (!nsrcs)
			return -EINVAL;

		if (!pskb_may_pull(skb,
				   len + sizeof(*grec) +
952
				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
953 954 955
			return -EINVAL;

		grec = (struct mld2_grec *)(skb->data + len);
956 957
		len += sizeof(*grec) +
		       sizeof(struct in6_addr) * ntohs(*nsrcs);
958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981

		/* We treat these as MLDv1 reports for now. */
		switch (grec->grec_type) {
		case MLD2_MODE_IS_INCLUDE:
		case MLD2_MODE_IS_EXCLUDE:
		case MLD2_CHANGE_TO_INCLUDE:
		case MLD2_CHANGE_TO_EXCLUDE:
		case MLD2_ALLOW_NEW_SOURCES:
		case MLD2_BLOCK_OLD_SOURCES:
			break;

		default:
			continue;
		}

		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
		if (!err)
			break;
	}

	return err;
}
#endif

982 983 984 985 986
/*
 * Add port to rotuer_list
 *  list is maintained ordered by pointer value
 *  and locked by br->multicast_lock and RCU
 */
987 988 989
static void br_multicast_add_router(struct net_bridge *br,
				    struct net_bridge_port *port)
{
990
	struct net_bridge_port *p;
991
	struct hlist_node *n, *slot = NULL;
992

993
	hlist_for_each_entry(p, n, &br->router_list, rlist) {
994 995 996
		if ((unsigned long) port >= (unsigned long) p)
			break;
		slot = n;
997 998
	}

999 1000
	if (slot)
		hlist_add_after_rcu(slot, &port->rlist);
1001 1002
	else
		hlist_add_head_rcu(&port->rlist, &br->router_list);
1003 1004
}

1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022
static void br_multicast_mark_router(struct net_bridge *br,
				     struct net_bridge_port *port)
{
	unsigned long now = jiffies;

	if (!port) {
		if (br->multicast_router == 1)
			mod_timer(&br->multicast_router_timer,
				  now + br->multicast_querier_interval);
		return;
	}

	if (port->multicast_router != 1)
		return;

	if (!hlist_unhashed(&port->rlist))
		goto timer;

1023
	br_multicast_add_router(br, port);
1024 1025 1026 1027 1028 1029 1030 1031

timer:
	mod_timer(&port->multicast_router_timer,
		  now + br->multicast_querier_interval);
}

static void br_multicast_query_received(struct net_bridge *br,
					struct net_bridge_port *port,
1032
					int saddr)
1033 1034 1035 1036 1037 1038 1039 1040 1041 1042
{
	if (saddr)
		mod_timer(&br->multicast_querier_timer,
			  jiffies + br->multicast_querier_interval);
	else if (timer_pending(&br->multicast_querier_timer))
		return;

	br_multicast_mark_router(br, port);
}

1043 1044 1045
static int br_ip4_multicast_query(struct net_bridge *br,
				  struct net_bridge_port *port,
				  struct sk_buff *skb)
1046
{
1047
	const struct iphdr *iph = ip_hdr(skb);
1048 1049 1050 1051
	struct igmphdr *ih = igmp_hdr(skb);
	struct net_bridge_mdb_entry *mp;
	struct igmpv3_query *ih3;
	struct net_bridge_port_group *p;
1052
	struct net_bridge_port_group __rcu **pp;
1053 1054 1055
	unsigned long max_delay;
	unsigned long now = jiffies;
	__be32 group;
1056
	int err = 0;
1057 1058 1059 1060 1061 1062

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) ||
	    (port && port->state == BR_STATE_DISABLED))
		goto out;

1063
	br_multicast_query_received(br, port, !!iph->saddr);
1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074

	group = ih->group;

	if (skb->len == sizeof(*ih)) {
		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);

		if (!max_delay) {
			max_delay = 10 * HZ;
			group = 0;
		}
	} else {
1075 1076 1077 1078
		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
			err = -EINVAL;
			goto out;
		}
1079 1080 1081

		ih3 = igmpv3_query_hdr(skb);
		if (ih3->nsrcs)
1082
			goto out;
1083

1084 1085
		max_delay = ih3->code ?
			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1086 1087 1088 1089 1090
	}

	if (!group)
		goto out;

1091
	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
1092 1093 1094 1095 1096
	if (!mp)
		goto out;

	max_delay *= br->multicast_last_member_count;

1097
	if (mp->mglist &&
1098 1099 1100 1101 1102
	    (timer_pending(&mp->timer) ?
	     time_after(mp->timer.expires, now + max_delay) :
	     try_to_del_timer_sync(&mp->timer) >= 0))
		mod_timer(&mp->timer, now + max_delay);

1103 1104 1105
	for (pp = &mp->ports;
	     (p = mlock_dereference(*pp, br)) != NULL;
	     pp = &p->next) {
1106 1107 1108
		if (timer_pending(&p->timer) ?
		    time_after(p->timer.expires, now + max_delay) :
		    try_to_del_timer_sync(&p->timer) >= 0)
1109
			mod_timer(&p->timer, now + max_delay);
1110 1111 1112 1113
	}

out:
	spin_unlock(&br->multicast_lock);
1114
	return err;
1115 1116
}

E
Eric Dumazet 已提交
1117
#if IS_ENABLED(CONFIG_IPV6)
1118 1119 1120 1121
static int br_ip6_multicast_query(struct net_bridge *br,
				  struct net_bridge_port *port,
				  struct sk_buff *skb)
{
1122
	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1123 1124 1125
	struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
	struct net_bridge_mdb_entry *mp;
	struct mld2_query *mld2q;
1126 1127
	struct net_bridge_port_group *p;
	struct net_bridge_port_group __rcu **pp;
1128 1129
	unsigned long max_delay;
	unsigned long now = jiffies;
1130
	const struct in6_addr *group = NULL;
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162
	int err = 0;

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) ||
	    (port && port->state == BR_STATE_DISABLED))
		goto out;

	br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));

	if (skb->len == sizeof(*mld)) {
		if (!pskb_may_pull(skb, sizeof(*mld))) {
			err = -EINVAL;
			goto out;
		}
		mld = (struct mld_msg *) icmp6_hdr(skb);
		max_delay = msecs_to_jiffies(htons(mld->mld_maxdelay));
		if (max_delay)
			group = &mld->mld_mca;
	} else if (skb->len >= sizeof(*mld2q)) {
		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
			err = -EINVAL;
			goto out;
		}
		mld2q = (struct mld2_query *)icmp6_hdr(skb);
		if (!mld2q->mld2q_nsrcs)
			group = &mld2q->mld2q_mca;
		max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(mld2q->mld2q_mrc) : 1;
	}

	if (!group)
		goto out;

1163
	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
1164 1165 1166 1167
	if (!mp)
		goto out;

	max_delay *= br->multicast_last_member_count;
1168
	if (mp->mglist &&
1169 1170 1171 1172 1173
	    (timer_pending(&mp->timer) ?
	     time_after(mp->timer.expires, now + max_delay) :
	     try_to_del_timer_sync(&mp->timer) >= 0))
		mod_timer(&mp->timer, now + max_delay);

1174 1175 1176
	for (pp = &mp->ports;
	     (p = mlock_dereference(*pp, br)) != NULL;
	     pp = &p->next) {
1177 1178 1179
		if (timer_pending(&p->timer) ?
		    time_after(p->timer.expires, now + max_delay) :
		    try_to_del_timer_sync(&p->timer) >= 0)
1180
			mod_timer(&p->timer, now + max_delay);
1181 1182 1183 1184 1185 1186 1187 1188
	}

out:
	spin_unlock(&br->multicast_lock);
	return err;
}
#endif

1189 1190
static void br_multicast_leave_group(struct net_bridge *br,
				     struct net_bridge_port *port,
1191
				     struct br_ip *group)
1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204
{
	struct net_bridge_mdb_htable *mdb;
	struct net_bridge_mdb_entry *mp;
	struct net_bridge_port_group *p;
	unsigned long now;
	unsigned long time;

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) ||
	    (port && port->state == BR_STATE_DISABLED) ||
	    timer_pending(&br->multicast_querier_timer))
		goto out;

1205
	mdb = mlock_dereference(br->mdb, br);
1206 1207 1208 1209 1210 1211 1212 1213 1214
	mp = br_mdb_ip_get(mdb, group);
	if (!mp)
		goto out;

	now = jiffies;
	time = now + br->multicast_last_member_count *
		     br->multicast_last_member_interval;

	if (!port) {
1215
		if (mp->mglist &&
1216 1217 1218 1219 1220 1221 1222 1223 1224
		    (timer_pending(&mp->timer) ?
		     time_after(mp->timer.expires, time) :
		     try_to_del_timer_sync(&mp->timer) >= 0)) {
			mod_timer(&mp->timer, time);
		}

		goto out;
	}

1225 1226 1227
	for (p = mlock_dereference(mp->ports, br);
	     p != NULL;
	     p = mlock_dereference(p->next, br)) {
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244
		if (p->port != port)
			continue;

		if (!hlist_unhashed(&p->mglist) &&
		    (timer_pending(&p->timer) ?
		     time_after(p->timer.expires, time) :
		     try_to_del_timer_sync(&p->timer) >= 0)) {
			mod_timer(&p->timer, time);
		}

		break;
	}

out:
	spin_unlock(&br->multicast_lock);
}

1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259
static void br_ip4_multicast_leave_group(struct net_bridge *br,
					 struct net_bridge_port *port,
					 __be32 group)
{
	struct br_ip br_group;

	if (ipv4_is_local_multicast(group))
		return;

	br_group.u.ip4 = group;
	br_group.proto = htons(ETH_P_IP);

	br_multicast_leave_group(br, port, &br_group);
}

E
Eric Dumazet 已提交
1260
#if IS_ENABLED(CONFIG_IPV6)
1261 1262 1263 1264 1265 1266
static void br_ip6_multicast_leave_group(struct net_bridge *br,
					 struct net_bridge_port *port,
					 const struct in6_addr *group)
{
	struct br_ip br_group;

1267
	if (!ipv6_is_transient_multicast(group))
1268 1269
		return;

A
Alexey Dobriyan 已提交
1270
	br_group.u.ip6 = *group;
1271 1272 1273 1274 1275
	br_group.proto = htons(ETH_P_IPV6);

	br_multicast_leave_group(br, port, &br_group);
}
#endif
1276

1277 1278 1279 1280 1281
static int br_multicast_ipv4_rcv(struct net_bridge *br,
				 struct net_bridge_port *port,
				 struct sk_buff *skb)
{
	struct sk_buff *skb2 = skb;
1282
	const struct iphdr *iph;
1283
	struct igmphdr *ih;
1284 1285
	unsigned int len;
	unsigned int offset;
1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304
	int err;

	/* We treat OOM as packet loss for now. */
	if (!pskb_may_pull(skb, sizeof(*iph)))
		return -EINVAL;

	iph = ip_hdr(skb);

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

	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
		return -EINVAL;

	iph = ip_hdr(skb);

	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
		return -EINVAL;

1305 1306 1307
	if (iph->protocol != IPPROTO_IGMP) {
		if ((iph->daddr & IGMP_LOCAL_GROUP_MASK) != IGMP_LOCAL_GROUP)
			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1308
		return 0;
1309
	}
1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321

	len = ntohs(iph->tot_len);
	if (skb->len < len || len < ip_hdrlen(skb))
		return -EINVAL;

	if (skb->len > len) {
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (!skb2)
			return -ENOMEM;

		err = pskb_trim_rcsum(skb2, len);
		if (err)
1322
			goto err_out;
1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341
	}

	len -= ip_hdrlen(skb2);
	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
	__skb_pull(skb2, offset);
	skb_reset_transport_header(skb2);

	err = -EINVAL;
	if (!pskb_may_pull(skb2, sizeof(*ih)))
		goto out;

	switch (skb2->ip_summed) {
	case CHECKSUM_COMPLETE:
		if (!csum_fold(skb2->csum))
			break;
		/* fall through */
	case CHECKSUM_NONE:
		skb2->csum = 0;
		if (skb_checksum_complete(skb2))
1342
			goto out;
1343 1344 1345 1346 1347 1348 1349 1350 1351 1352
	}

	err = 0;

	BR_INPUT_SKB_CB(skb)->igmp = 1;
	ih = igmp_hdr(skb2);

	switch (ih->type) {
	case IGMP_HOST_MEMBERSHIP_REPORT:
	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1353
		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1354
		err = br_ip4_multicast_add_group(br, port, ih->group);
1355 1356
		break;
	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1357
		err = br_ip4_multicast_igmp3_report(br, port, skb2);
1358 1359
		break;
	case IGMP_HOST_MEMBERSHIP_QUERY:
1360
		err = br_ip4_multicast_query(br, port, skb2);
1361 1362
		break;
	case IGMP_HOST_LEAVE_MESSAGE:
1363
		br_ip4_multicast_leave_group(br, port, ih->group);
1364 1365 1366 1367 1368
		break;
	}

out:
	__skb_push(skb2, offset);
1369
err_out:
1370 1371 1372 1373 1374
	if (skb2 != skb)
		kfree_skb(skb2);
	return err;
}

E
Eric Dumazet 已提交
1375
#if IS_ENABLED(CONFIG_IPV6)
1376 1377 1378 1379
static int br_multicast_ipv6_rcv(struct net_bridge *br,
				 struct net_bridge_port *port,
				 struct sk_buff *skb)
{
1380
	struct sk_buff *skb2;
1381
	const struct ipv6hdr *ip6h;
1382
	u8 icmp6_type;
1383
	u8 nexthdr;
1384
	__be16 frag_off;
1385
	unsigned int len;
K
Kulikov Vasiliy 已提交
1386
	int offset;
1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404
	int err;

	if (!pskb_may_pull(skb, sizeof(*ip6h)))
		return -EINVAL;

	ip6h = ipv6_hdr(skb);

	/*
	 * We're interested in MLD messages only.
	 *  - Version is 6
	 *  - MLD has always Router Alert hop-by-hop option
	 *  - But we do not support jumbrograms.
	 */
	if (ip6h->version != 6 ||
	    ip6h->nexthdr != IPPROTO_HOPOPTS ||
	    ip6h->payload_len == 0)
		return 0;

1405
	len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1406 1407 1408 1409
	if (skb->len < len)
		return -EINVAL;

	nexthdr = ip6h->nexthdr;
1410
	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1411 1412 1413 1414 1415 1416 1417 1418 1419

	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
		return 0;

	/* Okay, we found ICMPv6 header */
	skb2 = skb_clone(skb, GFP_ATOMIC);
	if (!skb2)
		return -ENOMEM;

1420 1421 1422 1423
	err = -EINVAL;
	if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
		goto out;

1424 1425 1426 1427
	len -= offset - skb_network_offset(skb2);

	__skb_pull(skb2, offset);
	skb_reset_transport_header(skb2);
1428 1429
	skb_postpull_rcsum(skb2, skb_network_header(skb2),
			   skb_network_header_len(skb2));
1430

1431
	icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1432

1433
	switch (icmp6_type) {
1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448
	case ICMPV6_MGM_QUERY:
	case ICMPV6_MGM_REPORT:
	case ICMPV6_MGM_REDUCTION:
	case ICMPV6_MLD2_REPORT:
		break;
	default:
		err = 0;
		goto out;
	}

	/* Okay, we found MLD message. Check further. */
	if (skb2->len > len) {
		err = pskb_trim_rcsum(skb2, len);
		if (err)
			goto out;
1449
		err = -EINVAL;
1450 1451
	}

1452 1453
	ip6h = ipv6_hdr(skb2);

1454 1455
	switch (skb2->ip_summed) {
	case CHECKSUM_COMPLETE:
1456 1457
		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
					IPPROTO_ICMPV6, skb2->csum))
1458 1459 1460
			break;
		/*FALLTHROUGH*/
	case CHECKSUM_NONE:
1461 1462 1463 1464 1465
		skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
							&ip6h->daddr,
							skb2->len,
							IPPROTO_ICMPV6, 0));
		if (__skb_checksum_complete(skb2))
1466 1467 1468 1469 1470 1471 1472
			goto out;
	}

	err = 0;

	BR_INPUT_SKB_CB(skb)->igmp = 1;

1473
	switch (icmp6_type) {
1474 1475
	case ICMPV6_MGM_REPORT:
	    {
1476 1477 1478 1479 1480 1481
		struct mld_msg *mld;
		if (!pskb_may_pull(skb2, sizeof(*mld))) {
			err = -EINVAL;
			goto out;
		}
		mld = (struct mld_msg *)skb_transport_header(skb2);
1482
		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493
		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
		break;
	    }
	case ICMPV6_MLD2_REPORT:
		err = br_ip6_multicast_mld2_report(br, port, skb2);
		break;
	case ICMPV6_MGM_QUERY:
		err = br_ip6_multicast_query(br, port, skb2);
		break;
	case ICMPV6_MGM_REDUCTION:
	    {
1494 1495 1496 1497 1498 1499
		struct mld_msg *mld;
		if (!pskb_may_pull(skb2, sizeof(*mld))) {
			err = -EINVAL;
			goto out;
		}
		mld = (struct mld_msg *)skb_transport_header(skb2);
1500 1501 1502 1503 1504
		br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
	    }
	}

out:
1505
	kfree_skb(skb2);
1506 1507 1508 1509
	return err;
}
#endif

1510 1511 1512
int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
		     struct sk_buff *skb)
{
1513 1514 1515
	BR_INPUT_SKB_CB(skb)->igmp = 0;
	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;

1516 1517 1518 1519 1520 1521
	if (br->multicast_disabled)
		return 0;

	switch (skb->protocol) {
	case htons(ETH_P_IP):
		return br_multicast_ipv4_rcv(br, port, skb);
E
Eric Dumazet 已提交
1522
#if IS_ENABLED(CONFIG_IPV6)
1523 1524 1525
	case htons(ETH_P_IPV6):
		return br_multicast_ipv6_rcv(br, port, skb);
#endif
1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592
	}

	return 0;
}

static void br_multicast_query_expired(unsigned long data)
{
	struct net_bridge *br = (void *)data;

	spin_lock(&br->multicast_lock);
	if (br->multicast_startup_queries_sent <
	    br->multicast_startup_query_count)
		br->multicast_startup_queries_sent++;

	br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);

	spin_unlock(&br->multicast_lock);
}

void br_multicast_init(struct net_bridge *br)
{
	br->hash_elasticity = 4;
	br->hash_max = 512;

	br->multicast_router = 1;
	br->multicast_last_member_count = 2;
	br->multicast_startup_query_count = 2;

	br->multicast_last_member_interval = HZ;
	br->multicast_query_response_interval = 10 * HZ;
	br->multicast_startup_query_interval = 125 * HZ / 4;
	br->multicast_query_interval = 125 * HZ;
	br->multicast_querier_interval = 255 * HZ;
	br->multicast_membership_interval = 260 * HZ;

	spin_lock_init(&br->multicast_lock);
	setup_timer(&br->multicast_router_timer,
		    br_multicast_local_router_expired, 0);
	setup_timer(&br->multicast_querier_timer,
		    br_multicast_local_router_expired, 0);
	setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
		    (unsigned long)br);
}

void br_multicast_open(struct net_bridge *br)
{
	br->multicast_startup_queries_sent = 0;

	if (br->multicast_disabled)
		return;

	mod_timer(&br->multicast_query_timer, jiffies);
}

void br_multicast_stop(struct net_bridge *br)
{
	struct net_bridge_mdb_htable *mdb;
	struct net_bridge_mdb_entry *mp;
	struct hlist_node *p, *n;
	u32 ver;
	int i;

	del_timer_sync(&br->multicast_router_timer);
	del_timer_sync(&br->multicast_querier_timer);
	del_timer_sync(&br->multicast_query_timer);

	spin_lock_bh(&br->multicast_lock);
1593
	mdb = mlock_dereference(br->mdb, br);
1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609
	if (!mdb)
		goto out;

	br->mdb = NULL;

	ver = mdb->ver;
	for (i = 0; i < mdb->max; i++) {
		hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
					  hlist[ver]) {
			del_timer(&mp->timer);
			call_rcu_bh(&mp->rcu, br_multicast_free_group);
		}
	}

	if (mdb->old) {
		spin_unlock_bh(&br->multicast_lock);
1610
		rcu_barrier_bh();
1611 1612 1613 1614 1615 1616 1617 1618 1619 1620
		spin_lock_bh(&br->multicast_lock);
		WARN_ON(mdb->old);
	}

	mdb->old = mdb;
	call_rcu_bh(&mdb->rcu, br_mdb_free);

out:
	spin_unlock_bh(&br->multicast_lock);
}
1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690

int br_multicast_set_router(struct net_bridge *br, unsigned long val)
{
	int err = -ENOENT;

	spin_lock_bh(&br->multicast_lock);
	if (!netif_running(br->dev))
		goto unlock;

	switch (val) {
	case 0:
	case 2:
		del_timer(&br->multicast_router_timer);
		/* fall through */
	case 1:
		br->multicast_router = val;
		err = 0;
		break;

	default:
		err = -EINVAL;
		break;
	}

unlock:
	spin_unlock_bh(&br->multicast_lock);

	return err;
}

int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
{
	struct net_bridge *br = p->br;
	int err = -ENOENT;

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
		goto unlock;

	switch (val) {
	case 0:
	case 1:
	case 2:
		p->multicast_router = val;
		err = 0;

		if (val < 2 && !hlist_unhashed(&p->rlist))
			hlist_del_init_rcu(&p->rlist);

		if (val == 1)
			break;

		del_timer(&p->multicast_router_timer);

		if (val == 0)
			break;

		br_multicast_add_router(br, p);
		break;

	default:
		err = -EINVAL;
		break;
	}

unlock:
	spin_unlock(&br->multicast_lock);

	return err;
}
1691 1692 1693 1694

int br_multicast_toggle(struct net_bridge *br, unsigned long val)
{
	struct net_bridge_port *port;
1695
	int err = 0;
1696
	struct net_bridge_mdb_htable *mdb;
1697

1698
	spin_lock_bh(&br->multicast_lock);
1699 1700 1701 1702 1703 1704 1705
	if (br->multicast_disabled == !val)
		goto unlock;

	br->multicast_disabled = !val;
	if (br->multicast_disabled)
		goto unlock;

1706 1707 1708
	if (!netif_running(br->dev))
		goto unlock;

1709 1710 1711
	mdb = mlock_dereference(br->mdb, br);
	if (mdb) {
		if (mdb->old) {
1712 1713 1714 1715 1716 1717
			err = -EEXIST;
rollback:
			br->multicast_disabled = !!val;
			goto unlock;
		}

1718
		err = br_mdb_rehash(&br->mdb, mdb->max,
1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733
				    br->hash_elasticity);
		if (err)
			goto rollback;
	}

	br_multicast_open(br);
	list_for_each_entry(port, &br->port_list, list) {
		if (port->state == BR_STATE_DISABLED ||
		    port->state == BR_STATE_BLOCKING)
			continue;

		__br_multicast_enable_port(port);
	}

unlock:
1734
	spin_unlock_bh(&br->multicast_lock);
1735 1736 1737

	return err;
}
1738 1739 1740 1741 1742

int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
{
	int err = -ENOENT;
	u32 old;
1743
	struct net_bridge_mdb_htable *mdb;
1744 1745 1746 1747 1748 1749 1750 1751

	spin_lock(&br->multicast_lock);
	if (!netif_running(br->dev))
		goto unlock;

	err = -EINVAL;
	if (!is_power_of_2(val))
		goto unlock;
1752 1753 1754

	mdb = mlock_dereference(br->mdb, br);
	if (mdb && val < mdb->size)
1755 1756 1757 1758 1759 1760 1761
		goto unlock;

	err = 0;

	old = br->hash_max;
	br->hash_max = val;

1762 1763
	if (mdb) {
		if (mdb->old) {
1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780
			err = -EEXIST;
rollback:
			br->hash_max = old;
			goto unlock;
		}

		err = br_mdb_rehash(&br->mdb, br->hash_max,
				    br->hash_elasticity);
		if (err)
			goto rollback;
	}

unlock:
	spin_unlock(&br->multicast_lock);

	return err;
}