Commit 617fe29d authored by Daniel Borkmann's avatar Daniel Borkmann Committed by David S. Miller
Browse files

net: ipv6: only invalidate previously tokenized addresses 



Instead of invalidating all IPv6 addresses with global scope
when one decides to use IPv6 tokens, we should only invalidate
previous tokens and leave the rest intact until they expire
eventually (or are intact forever). For doing this less greedy
approach, we're adding a bool at the end of inet6_ifaddr structure
instead, for two reasons: i) per-inet6_ifaddr flag space is
already used up, making it wider might not be a good idea,
since ii) also we do not necessarily need to export this
information into user space.

Suggested-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fc403832

include/net/if_inet6.h

+2 −0
Original line number Diff line number Diff line
@@ -71,6 +71,8 @@ struct inet6_ifaddr { 
	struct inet6_ifaddr	*ifpub;

	int			regen_count;

#endif

	bool			tokenized;



	struct rcu_head		rcu;

};

net/ipv6/addrconf.c

+5 −2
Original line number Diff line number Diff line
@@ -878,6 +878,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen, 
	ifa->prefix_len = pfxlen;

	ifa->flags = flags | IFA_F_TENTATIVE;

	ifa->cstamp = ifa->tstamp = jiffies;

	ifa->tokenized = false;



	ifa->rt = rt;
@@ -2134,6 +2135,7 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao) 
		struct inet6_ifaddr *ifp;

		struct in6_addr addr;

		int create = 0, update_lft = 0;

		bool tokenized = false;



		if (pinfo->prefix_len == 64) {

			memcpy(&addr, &pinfo->prefix, 8);
@@ -2143,6 +2145,7 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao) 
				memcpy(addr.s6_addr + 8,

				       in6_dev->token.s6_addr + 8, 8);

				read_unlock_bh(&in6_dev->lock);

				tokenized = true;

			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&

				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {

				in6_dev_put(in6_dev);
@@ -2185,6 +2188,7 @@ ok: 


			update_lft = create = 1;

			ifp->cstamp = jiffies;

			ifp->tokenized = tokenized;

			addrconf_dad_start(ifp);

		}
@@ -4339,8 +4343,7 @@ static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token) 
	/* Well, that's kinda nasty ... */

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

		spin_lock(&ifp->lock);

		if (ipv6_addr_src_scope(&ifp->addr) ==

		    IPV6_ADDR_SCOPE_GLOBAL) {

		if (ifp->tokenized) {

			ifp->valid_lft = 0;

			ifp->prefered_lft = 0;

		}

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