path: root/net/bridge/br_mdb.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/err.h>
#include <linux/igmp.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rculist.h>
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <net/ip.h>
#include <net/netlink.h>
#include <net/switchdev.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#include <net/addrconf.h>
#endif

#include "br_private.h"

static bool br_rports_have_mc_router(struct net_bridge_mcast *brmctx)
{
#if IS_ENABLED(CONFIG_IPV6)
	return !hlist_empty(&brmctx->ip4_mc_router_list) ||
	       !hlist_empty(&brmctx->ip6_mc_router_list);
#else
	return !hlist_empty(&brmctx->ip4_mc_router_list);
#endif
}

static bool
br_ip4_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
{
	*timer = br_timer_value(&port->multicast_ctx.ip4_mc_router_timer);
	return !hlist_unhashed(&port->multicast_ctx.ip4_rlist);
}

static bool
br_ip6_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
{
#if IS_ENABLED(CONFIG_IPV6)
	*timer = br_timer_value(&port->multicast_ctx.ip6_mc_router_timer);
	return !hlist_unhashed(&port->multicast_ctx.ip6_rlist);
#else
	*timer = 0;
	return false;
#endif
}

static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
			       struct net_device *dev)
{
	struct net_bridge *br = netdev_priv(dev);
	bool have_ip4_mc_rtr, have_ip6_mc_rtr;
	unsigned long ip4_timer, ip6_timer;
	struct nlattr *nest, *port_nest;
	struct net_bridge_port *p;

	if (!br->multicast_ctx.multicast_router)
		return 0;

	if (!br_rports_have_mc_router(&br->multicast_ctx))
		return 0;

	nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
	if (nest == NULL)
		return -EMSGSIZE;

	list_for_each_entry_rcu(p, &br->port_list, list) {
		have_ip4_mc_rtr = br_ip4_rports_get_timer(p, &ip4_timer);
		have_ip6_mc_rtr = br_ip6_rports_get_timer(p, &ip6_timer);

		if (!have_ip4_mc_rtr && !have_ip6_mc_rtr)
			continue;

		port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
		if (!port_nest)
			goto fail;

		if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
		    nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
				max(ip4_timer, ip6_timer)) ||
		    nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
			       p->multicast_ctx.multicast_router) ||
		    (have_ip4_mc_rtr &&
		     nla_put_u32(skb, MDBA_ROUTER_PATTR_INET_TIMER,
				 ip4_timer