Commit b173ee48 authored by Hannes Frederic Sowa's avatar Hannes Frederic Sowa Committed by David S. Miller
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ipv6: resend MLD report if a link-local address completes DAD 



RFC3590/RFC3810 specifies we should resend MLD reports as soon as a
valid link-local address is available.

We now use the valid_ll_addr_cnt to check if it is necessary to resend
a new report.

Changes since Flavio Leitner's version:
a) adapt for valid_ll_addr_cnt
b) resend first reports directly in the path and just arm the timer for
   mc_qrv-1 resends.

Reported-by: default avatarFlavio Leitner <fleitner@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: default avatarFlavio Leitner <fbl@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1ec047eb

include/net/addrconf.h

+1 −0
Original line number Diff line number Diff line
@@ -155,6 +155,7 @@ extern bool ipv6_chk_mcast_addr(struct net_device *dev, 
				const struct in6_addr *group,

				const struct in6_addr *src_addr);



extern void ipv6_mc_dad_complete(struct inet6_dev *idev);

/*

 * identify MLD packets for MLD filter exceptions

 */

include/net/if_inet6.h

+2 −0
Original line number Diff line number Diff line
@@ -174,10 +174,12 @@ struct inet6_dev { 
	unsigned char		mc_qrv;

	unsigned char		mc_gq_running;

	unsigned char		mc_ifc_count;

	unsigned char		mc_dad_count;

	unsigned long		mc_v1_seen;

	unsigned long		mc_maxdelay;

	struct timer_list	mc_gq_timer;	/* general query timer */

	struct timer_list	mc_ifc_timer;	/* interface change timer */

	struct timer_list	mc_dad_timer;	/* dad complete mc timer */



	struct ifacaddr6	*ac_list;

	rwlock_t		lock;

net/ipv6/addrconf.c

+12 −5
Original line number Diff line number Diff line
@@ -3277,7 +3277,7 @@ static void addrconf_dad_completed(struct inet6_ifaddr *ifp) 
{

	struct net_device *dev = ifp->idev->dev;

	struct in6_addr lladdr;

	bool send_rs;

	bool send_rs, send_mld;



	addrconf_del_dad_timer(ifp);
@@ -3293,14 +3293,21 @@ static void addrconf_dad_completed(struct inet6_ifaddr *ifp) 


	read_lock_bh(&ifp->idev->lock);

	spin_lock(&ifp->lock);

	send_rs = ipv6_accept_ra(ifp->idev) &&

		  ifp->idev->cnf.rtr_solicits > 0 &&

		  (dev->flags&IFF_LOOPBACK) == 0 &&

		  ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL &&

	send_mld = ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL &&

		   ifp->idev->valid_ll_addr_cnt == 1;

	send_rs = send_mld &&

		  ipv6_accept_ra(ifp->idev) &&

		  ifp->idev->cnf.rtr_solicits > 0 &&

		  (dev->flags&IFF_LOOPBACK) == 0;

	spin_unlock(&ifp->lock);

	read_unlock_bh(&ifp->idev->lock);



	/* While dad is in progress mld report's source address is in6_addrany.

	 * Resend with proper ll now.

	 */

	if (send_mld)

		ipv6_mc_dad_complete(ifp->idev);



	if (send_rs) {

		/*

		 *	If a host as already performed a random delay

net/ipv6/mcast.c

+52 −0
Original line number Diff line number Diff line
@@ -999,6 +999,14 @@ static void mld_ifc_start_timer(struct inet6_dev *idev, int delay) 
		in6_dev_hold(idev);

}



static void mld_dad_start_timer(struct inet6_dev *idev, int delay)

{

	int tv = net_random() % delay;



	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))

		in6_dev_hold(idev);

}



/*

 *	IGMP handling (alias multicast ICMPv6 messages)

 */
@@ -1815,6 +1823,46 @@ err_out: 
	goto out;

}



static void mld_resend_report(struct inet6_dev *idev)

{

	if (MLD_V1_SEEN(idev)) {

		struct ifmcaddr6 *mcaddr;

		read_lock_bh(&idev->lock);

		for (mcaddr = idev->mc_list; mcaddr; mcaddr = mcaddr->next) {

			if (!(mcaddr->mca_flags & MAF_NOREPORT))

				igmp6_send(&mcaddr->mca_addr, idev->dev,

					   ICMPV6_MGM_REPORT);

		}

		read_unlock_bh(&idev->lock);

	} else {

		mld_send_report(idev, NULL);

	}

}



void ipv6_mc_dad_complete(struct inet6_dev *idev)

{

	idev->mc_dad_count = idev->mc_qrv;

	if (idev->mc_dad_count) {

		mld_resend_report(idev);

		idev->mc_dad_count--;

		if (idev->mc_dad_count)

			mld_dad_start_timer(idev, idev->mc_maxdelay);

	}

}



static void mld_dad_timer_expire(unsigned long data)

{

	struct inet6_dev *idev = (struct inet6_dev *)data;



	mld_resend_report(idev);

	if (idev->mc_dad_count) {

		idev->mc_dad_count--;

		if (idev->mc_dad_count)

			mld_dad_start_timer(idev, idev->mc_maxdelay);

	}

	__in6_dev_put(idev);

}



static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,

	const struct in6_addr *psfsrc)

{
@@ -2232,6 +2280,8 @@ void ipv6_mc_down(struct inet6_dev *idev) 
	idev->mc_gq_running = 0;

	if (del_timer(&idev->mc_gq_timer))

		__in6_dev_put(idev);

	if (del_timer(&idev->mc_dad_timer))

		__in6_dev_put(idev);



	for (i = idev->mc_list; i; i=i->next)

		igmp6_group_dropped(i);
@@ -2268,6 +2318,8 @@ void ipv6_mc_init_dev(struct inet6_dev *idev) 
	idev->mc_ifc_count = 0;

	setup_timer(&idev->mc_ifc_timer, mld_ifc_timer_expire,

			(unsigned long)idev);

	setup_timer(&idev->mc_dad_timer, mld_dad_timer_expire,

		    (unsigned long)idev);

	idev->mc_qrv = MLD_QRV_DEFAULT;

	idev->mc_maxdelay = IGMP6_UNSOLICITED_IVAL;

	idev->mc_v1_seen = 0;

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