ipv6: unify conntrack reassembly expire code with standard one
Two years ago, Shan Wei tried to fix this:
http://patchwork.ozlabs.org/patch/43905/
The problem is that RFC2460 requires an ICMP Time
Exceeded -- Fragment Reassembly Time Exceeded message should be
sent to the source of that fragment, if the defragmentation
times out.
"
If insufficient fragments are received to complete reassembly of a
packet within 60 seconds of the reception of the first-arriving
fragment of that packet, reassembly of that packet must be
abandoned and all the fragments that have been received for that
packet must be discarded. If the first fragment (i.e., the one
with a Fragment Offset of zero) has been received, an ICMP Time
Exceeded -- Fragment Reassembly Time Exceeded message should be
sent to the source of that fragment.
"
As Herbert suggested, we could actually use the standard IPv6
reassembly code which follows RFC2460.
With this patch applied, I can see ICMP Time Exceeded sent
from the receiver when the sender sent out 3/4 fragmented
IPv6 UDP packet.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Michal Kubeček <mkubecek@suse.cz>
Cc: David Miller <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 4ff9af6..0ee5533 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -65,24 +65,6 @@
#define FRAG6_CB(skb) ((struct ip6frag_skb_cb*)((skb)->cb))
-/*
- * Equivalent of ipv4 struct ipq
- */
-
-struct frag_queue
-{
- struct inet_frag_queue q;
-
- __be32 id; /* fragment id */
- u32 user;
- struct in6_addr saddr;
- struct in6_addr daddr;
-
- int iif;
- unsigned int csum;
- __u16 nhoffset;
-};
-
static struct inet_frags ip6_frags;
int ip6_frag_nqueues(struct net *net)
@@ -159,21 +141,6 @@
}
EXPORT_SYMBOL(ip6_frag_init);
-/* Destruction primitives. */
-
-static __inline__ void fq_put(struct frag_queue *fq)
-{
- inet_frag_put(&fq->q, &ip6_frags);
-}
-
-/* Kill fq entry. It is not destroyed immediately,
- * because caller (and someone more) holds reference count.
- */
-static __inline__ void fq_kill(struct frag_queue *fq)
-{
- inet_frag_kill(&fq->q, &ip6_frags);
-}
-
static void ip6_evictor(struct net *net, struct inet6_dev *idev)
{
int evicted;
@@ -183,22 +150,18 @@
IP6_ADD_STATS_BH(net, idev, IPSTATS_MIB_REASMFAILS, evicted);
}
-static void ip6_frag_expire(unsigned long data)
+void ip6_expire_frag_queue(struct net *net, struct frag_queue *fq,
+ struct inet_frags *frags)
{
- struct frag_queue *fq;
struct net_device *dev = NULL;
- struct net *net;
-
- fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
spin_lock(&fq->q.lock);
if (fq->q.last_in & INET_FRAG_COMPLETE)
goto out;
- fq_kill(fq);
+ inet_frag_kill(&fq->q, frags);
- net = container_of(fq->q.net, struct net, ipv6.frags);
rcu_read_lock();
dev = dev_get_by_index_rcu(net, fq->iif);
if (!dev)
@@ -222,7 +185,19 @@
rcu_read_unlock();
out:
spin_unlock(&fq->q.lock);
- fq_put(fq);
+ inet_frag_put(&fq->q, frags);
+}
+EXPORT_SYMBOL(ip6_expire_frag_queue);
+
+static void ip6_frag_expire(unsigned long data)
+{
+ struct frag_queue *fq;
+ struct net *net;
+
+ fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
+ net = container_of(fq->q.net, struct net, ipv6.frags);
+
+ ip6_expire_frag_queue(net, fq, &ip6_frags);
}
static __inline__ struct frag_queue *
@@ -391,7 +366,7 @@
return -1;
discard_fq:
- fq_kill(fq);
+ inet_frag_kill(&fq->q, &ip6_frags);
err:
IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
IPSTATS_MIB_REASMFAILS);
@@ -417,7 +392,7 @@
unsigned int nhoff;
int sum_truesize;
- fq_kill(fq);
+ inet_frag_kill(&fq->q, &ip6_frags);
/* Make the one we just received the head. */
if (prev) {
@@ -586,7 +561,7 @@
ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);
spin_unlock(&fq->q.lock);
- fq_put(fq);
+ inet_frag_put(&fq->q, &ip6_frags);
return ret;
}