Commit e5d64023 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'noprefixroute' 



Thomas Haller says:

====================
ipv6 addrconf: add IFA_F_NOPREFIXROUTE flag to suppress creation of IP6 routes

v1 -> v2: add a second commit, handling NOPREFIXROUTE in ip6_del_addr.
v2 -> v3: reword commit messages, code comments and some refactoring.
v3 -> v4: refactor, rename variables, add enum
v4 -> v5: rebase, so that patch applies cleanly to current net-next/master
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 6631c5ce 5b84efec

include/uapi/linux/if_addr.h

+1 −0
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ enum { 
#define IFA_F_TENTATIVE		0x40

#define IFA_F_PERMANENT		0x80

#define IFA_F_MANAGETEMPADDR	0x100

#define IFA_F_NOPREFIXROUTE	0x200



struct ifa_cacheinfo {

	__u32	ifa_prefered;

net/ipv6/addrconf.c

+122 −81
Original line number Diff line number Diff line
@@ -900,15 +900,95 @@ out: 
	goto out2;

}



enum cleanup_prefix_rt_t {

	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */

	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */

	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */

};



/*

 * Check, whether the prefix for ifp would still need a prefix route

 * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*

 * constants.

 *

 * 1) we don't purge prefix if address was not permanent.

 *    prefix is managed by its own lifetime.

 * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.

 * 3) if there are no addresses, delete prefix.

 * 4) if there are still other permanent address(es),

 *    corresponding prefix is still permanent.

 * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,

 *    don't purge the prefix, assume user space is managing it.

 * 6) otherwise, update prefix lifetime to the

 *    longest valid lifetime among the corresponding

 *    addresses on the device.

 *    Note: subsequent RA will update lifetime.

 **/

static enum cleanup_prefix_rt_t

check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)

{

	struct inet6_ifaddr *ifa;

	struct inet6_dev *idev = ifp->idev;

	unsigned long lifetime;

	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;



	*expires = jiffies;



	list_for_each_entry(ifa, &idev->addr_list, if_list) {

		if (ifa == ifp)

			continue;

		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,

				       ifp->prefix_len))

			continue;

		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))

			return CLEANUP_PREFIX_RT_NOP;



		action = CLEANUP_PREFIX_RT_EXPIRE;



		spin_lock(&ifa->lock);



		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);

		/*

		 * Note: Because this address is

		 * not permanent, lifetime <

		 * LONG_MAX / HZ here.

		 */

		if (time_before(*expires, ifa->tstamp + lifetime * HZ))

			*expires = ifa->tstamp + lifetime * HZ;

		spin_unlock(&ifa->lock);

	}



	return action;

}



static void

cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)

{

	struct rt6_info *rt;



	rt = addrconf_get_prefix_route(&ifp->addr,

				       ifp->prefix_len,

				       ifp->idev->dev,

				       0, RTF_GATEWAY | RTF_DEFAULT);

	if (rt) {

		if (del_rt)

			ip6_del_rt(rt);

		else {

			if (!(rt->rt6i_flags & RTF_EXPIRES))

				rt6_set_expires(rt, expires);

			ip6_rt_put(rt);

		}

	}

}





/* This function wants to get referenced ifp and releases it before return */



static void ipv6_del_addr(struct inet6_ifaddr *ifp)

{

	struct inet6_ifaddr *ifa, *ifn;

	struct inet6_dev *idev = ifp->idev;

	int state;

	int deleted = 0, onlink = 0;

	unsigned long expires = jiffies;

	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;

	unsigned long expires;



	spin_lock_bh(&ifp->state_lock);

	state = ifp->state;
@@ -922,7 +1002,7 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) 
	hlist_del_init_rcu(&ifp->addr_lst);

	spin_unlock_bh(&addrconf_hash_lock);



	write_lock_bh(&idev->lock);

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



	if (ifp->flags&IFA_F_TEMPORARY) {

		list_del(&ifp->tmp_list);
@@ -933,45 +1013,13 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) 
		__in6_ifa_put(ifp);

	}



	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {

		if (ifa == ifp) {

	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))

		action = check_cleanup_prefix_route(ifp, &expires);



	list_del_init(&ifp->if_list);

	__in6_ifa_put(ifp);



			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)

				break;

			deleted = 1;

			continue;

		} else if (ifp->flags & IFA_F_PERMANENT) {

			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,

					      ifp->prefix_len)) {

				if (ifa->flags & IFA_F_PERMANENT) {

					onlink = 1;

					if (deleted)

						break;

				} else {

					unsigned long lifetime;



					if (!onlink)

						onlink = -1;



					spin_lock(&ifa->lock);



					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);

					/*

					 * Note: Because this address is

					 * not permanent, lifetime <

					 * LONG_MAX / HZ here.

					 */

					if (time_before(expires,

							ifa->tstamp + lifetime * HZ))

						expires = ifa->tstamp + lifetime * HZ;

					spin_unlock(&ifa->lock);

				}

			}

		}

	}

	write_unlock_bh(&idev->lock);

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



	addrconf_del_dad_timer(ifp);
@@ -979,38 +1027,9 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp) 


	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);



	/*

	 * Purge or update corresponding prefix

	 *

	 * 1) we don't purge prefix here if address was not permanent.

	 *    prefix is managed by its own lifetime.

	 * 2) if there are no addresses, delete prefix.

	 * 3) if there are still other permanent address(es),

	 *    corresponding prefix is still permanent.

	 * 4) otherwise, update prefix lifetime to the

	 *    longest valid lifetime among the corresponding

	 *    addresses on the device.

	 *    Note: subsequent RA will update lifetime.

	 *

	 * --yoshfuji

	 */

	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {

		struct rt6_info *rt;



		rt = addrconf_get_prefix_route(&ifp->addr,

					       ifp->prefix_len,

					       ifp->idev->dev,

					       0, RTF_GATEWAY | RTF_DEFAULT);



		if (rt) {

			if (onlink == 0) {

				ip6_del_rt(rt);

				rt = NULL;

			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {

				rt6_set_expires(rt, expires);

			}

		}

		ip6_rt_put(rt);

	if (action != CLEANUP_PREFIX_RT_NOP) {

		cleanup_prefix_route(ifp, expires,

			action == CLEANUP_PREFIX_RT_DEL);

	}



	/* clean up prefsrc entries */
@@ -2434,8 +2453,11 @@ static int inet6_addr_add(struct net *net, int ifindex, 
			    valid_lft, prefered_lft);



	if (!IS_ERR(ifp)) {

		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {

			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,

					      expires, flags);

		}



		/*

		 * Note that section 3.1 of RFC 4429 indicates

		 * that the Optimistic flag should not be set for
@@ -3633,6 +3655,7 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags, 
	clock_t expires;

	unsigned long timeout;

	bool was_managetempaddr;

	bool had_prefixroute;



	if (!valid_lft || (prefered_lft > valid_lft))

		return -EINVAL;
@@ -3661,8 +3684,11 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags, 


	spin_lock_bh(&ifp->lock);

	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;

	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&

			  !(ifp->flags & IFA_F_NOPREFIXROUTE);

	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |

			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR);

			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |

			IFA_F_NOPREFIXROUTE);

	ifp->flags |= ifa_flags;

	ifp->tstamp = jiffies;

	ifp->valid_lft = valid_lft;
@@ -3672,8 +3698,22 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags, 
	if (!(ifp->flags&IFA_F_TENTATIVE))

		ipv6_ifa_notify(0, ifp);



	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {

		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,

				      expires, flags);

	} else if (had_prefixroute) {

		enum cleanup_prefix_rt_t action;

		unsigned long rt_expires;



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

		action = check_cleanup_prefix_route(ifp, &rt_expires);

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



		if (action != CLEANUP_PREFIX_RT_NOP) {

			cleanup_prefix_route(ifp, rt_expires,

				action == CLEANUP_PREFIX_RT_DEL);

		}

	}



	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {

		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
@@ -3727,7 +3767,8 @@ inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh) 
	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;



	/* We ignore other flags so far. */

	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR;

	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |

		     IFA_F_NOPREFIXROUTE;



	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);

	if (ifa == NULL) {

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