From 63fca65d08632fbec9d9b655f671cf08aa1aeeb8 Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Mon, 6 Feb 2017 23:14:15 +0200 Subject: [PATCH] net: add confirm_neigh method to dst_ops Add confirm_neigh method to dst_ops and use it from IPv4 and IPv6 to lookup and confirm the neighbour. Its usage via the new helper dst_confirm_neigh() should be restricted to MSG_PROBE users for performance reasons. For XFRM prefer the last tunnel address, if present. With help from Steffen Klassert. Signed-off-by: Julian Anastasov Acked-by: Steffen Klassert Signed-off-by: David S. Miller --- include/net/arp.h | 16 ++++++++++++++++ include/net/dst.h | 7 +++++++ include/net/dst_ops.h | 2 ++ include/net/ndisc.h | 17 +++++++++++++++++ net/ipv4/route.c | 19 +++++++++++++++++++ net/ipv6/route.c | 16 ++++++++++++++++ net/xfrm/xfrm_policy.c | 19 +++++++++++++++++++ 7 files changed, 96 insertions(+) diff --git a/include/net/arp.h b/include/net/arp.h index 5e0f891d476c..65619a2de6f4 100644 --- a/include/net/arp.h +++ b/include/net/arp.h @@ -35,6 +35,22 @@ static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 return n; } +static inline void __ipv4_confirm_neigh(struct net_device *dev, u32 key) +{ + struct neighbour *n; + + rcu_read_lock_bh(); + n = __ipv4_neigh_lookup_noref(dev, key); + if (n) { + unsigned long now = jiffies; + + /* avoid dirtying neighbour */ + if (n->confirmed != now) + n->confirmed = now; + } + rcu_read_unlock_bh(); +} + void arp_init(void); int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg); void arp_send(int type, int ptype, __be32 dest_ip, diff --git a/include/net/dst.h b/include/net/dst.h index 6835d224d47b..3a3b34b83b00 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -477,6 +477,13 @@ static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst return IS_ERR(n) ? NULL : n; } +static inline void dst_confirm_neigh(const struct dst_entry *dst, + const void *daddr) +{ + if (dst->ops->confirm_neigh) + dst->ops->confirm_neigh(dst, daddr); +} + static inline void dst_link_failure(struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); diff --git a/include/net/dst_ops.h b/include/net/dst_ops.h index 8a2b66d8d78d..c84b3287e38b 100644 --- a/include/net/dst_ops.h +++ b/include/net/dst_ops.h @@ -33,6 +33,8 @@ struct dst_ops { struct neighbour * (*neigh_lookup)(const struct dst_entry *dst, struct sk_buff *skb, const void *daddr); + void (*confirm_neigh)(const struct dst_entry *dst, + const void *daddr); struct kmem_cache *kmem_cachep; diff --git a/include/net/ndisc.h b/include/net/ndisc.h index d562a2fe4860..8a0214654b6b 100644 --- a/include/net/ndisc.h +++ b/include/net/ndisc.h @@ -391,6 +391,23 @@ static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, cons return n; } +static inline void __ipv6_confirm_neigh(struct net_device *dev, + const void *pkey) +{ + struct neighbour *n; + + rcu_read_lock_bh(); + n = __ipv6_neigh_lookup_noref(dev, pkey); + if (n) { + unsigned long now = jiffies; + + /* avoid dirtying neighbour */ + if (n->confirmed != now) + n->confirmed = now; + } + rcu_read_unlock_bh(); +} + int ndisc_init(void); int ndisc_late_init(void); diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 4b7c231c1aef..cb494a5050f7 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -154,6 +154,7 @@ static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, struct sk_buff *skb, const void *daddr); +static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr); static struct dst_ops ipv4_dst_ops = { .family = AF_INET, @@ -168,6 +169,7 @@ static struct dst_ops ipv4_dst_ops = { .redirect = ip_do_redirect, .local_out = __ip_local_out, .neigh_lookup = ipv4_neigh_lookup, + .confirm_neigh = ipv4_confirm_neigh, }; #define ECN_OR_COST(class) TC_PRIO_##class @@ -461,6 +463,23 @@ static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, return neigh_create(&arp_tbl, pkey, dev); } +static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr) +{ + struct net_device *dev = dst->dev; + const __be32 *pkey = daddr; + const struct rtable *rt; + + rt = (const struct rtable *)dst; + if (rt->rt_gateway) + pkey = (const __be32 *)&rt->rt_gateway; + else if (!daddr || + (rt->rt_flags & + (RTCF_MULTICAST | RTCF_BROADCAST | RTCF_LOCAL))) + return; + + __ipv4_confirm_neigh(dev, *(__force u32 *)pkey); +} + #define IP_IDENTS_SZ 2048u static atomic_t *ip_idents __read_mostly; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 8ffa24cc8899..98b183f1bc8b 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -223,6 +223,21 @@ static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, return neigh_create(&nd_tbl, daddr, dst->dev); } +static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr) +{ + struct net_device *dev = dst->dev; + struct rt6_info *rt = (struct rt6_info *)dst; + + daddr = choose_neigh_daddr(rt, NULL, daddr); + if (!daddr) + return; + if (dev->flags & (IFF_NOARP | IFF_LOOPBACK)) + return; + if (ipv6_addr_is_multicast((const struct in6_addr *)daddr)) + return; + __ipv6_confirm_neigh(dev, daddr); +} + static struct dst_ops ip6_dst_ops_template = { .family = AF_INET6, .gc = ip6_dst_gc, @@ -239,6 +254,7 @@ static struct dst_ops ip6_dst_ops_template = { .redirect = rt6_do_redirect, .local_out = __ip6_local_out, .neigh_lookup = ip6_neigh_lookup, + .confirm_neigh = ip6_confirm_neigh, }; static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst) diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 99ad1af2927f..0a0f63d3cc96 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -2856,6 +2856,23 @@ static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst, return dst->path->ops->neigh_lookup(dst, skb, daddr); } +static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr) +{ + const struct dst_entry *path = dst->path; + + for (; dst != path; dst = dst->child) { + const struct xfrm_state *xfrm = dst->xfrm; + + if (xfrm->props.mode == XFRM_MODE_TRANSPORT) + continue; + if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR) + daddr = xfrm->coaddr; + else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR)) + daddr = &xfrm->id.daddr; + } + path->ops->confirm_neigh(path, daddr); +} + int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo) { int err = 0; @@ -2882,6 +2899,8 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo) dst_ops->link_failure = xfrm_link_failure; if (likely(dst_ops->neigh_lookup == NULL)) dst_ops->neigh_lookup = xfrm_neigh_lookup; + if (likely(!dst_ops->confirm_neigh)) + dst_ops->confirm_neigh = xfrm_confirm_neigh; if (likely(afinfo->garbage_collect == NULL)) afinfo->garbage_collect = xfrm_garbage_collect_deferred; rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo); -- 2.20.1