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.
Signed-off-by: Julian Anastasov <j...@ssi.bg>
---
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 | 16 ++++++++++++++++
7 files changed, 93 insertions(+)
diff --git a/include/net/arp.h b/include/net/arp.h
index 5e0f891..65619a2 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 6835d22..3a3b34b 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 a0d443c..fc1bdb4 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 d562a2f..8a02146 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 fa5c037..682ff24 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 neighbour *ipv4_neigh_lookup(const struct
dst_entry *dst,
.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 890acac..4056d0e 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -217,6 +217,21 @@ 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,
@@ -233,6 +248,7 @@ static struct neighbour *ip6_neigh_lookup(const struct
dst_entry *dst,
.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 177e208..c010ee0 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2856,6 +2856,20 @@ 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;
+
+ if (path == dst) {
+ dst->ops->confirm_neigh(dst, daddr);
+ } else {
+ /* daddr can be from different family and we need the
+ * tunnel address. How to get it?
+ */
+ path->ops->confirm_neigh(path, NULL);
+ }
+}
+
int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
{
int err = 0;
@@ -2882,6 +2896,8 @@ 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);
--
1.9.3
