[PATCH 00/18] Netfilter/IPVS/OVS updates for net-next

[PATCH 00/18] Netfilter/IPVS/OVS updates for net-next

[Pablo Neira Ayuso]

Hi David,

The following patchset contains Netfilter/IPVS fixes and OVS NAT
support, more specifically this batch is composed of:

1) Fix a crash in ipset when performing a parallel flush/dump with
   set:list type, from Jozsef Kadlecsik.

2) Make sure NFACCT_FILTER_* netlink attributes are in place before
   accessing them, from Phil Turnbull.

3) Check return error code from ip_vs_fill_iph_skb_off() in IPVS SIP
   helper, from Arnd Bergmann.

4) Add workaround to IPVS to reschedule existing connections to new
   destination server by dropping the packet and wait for retransmission
   of TCP syn packet, from Julian Anastasov.

5) Allow connection rescheduling in IPVS when in CLOSE state, also
   from Julian.

6) Fix wrong offset of SIP Call-ID in IPVS helper, from Marco Angaroni.

7) Validate IPSET_ATTR_ETHER netlink attribute length, from Jozsef.

8) Check match/targetinfo netlink attribute size in nft_compat,
   patch from Florian Westphal.

9) Check for integer overflow on 32-bit systems in x_tables, from
   Florian Westphal.

Several patches from Jarno Rajahalme to prepare the introduction of
NAT support to OVS based on the Netfilter infrastructure:

10) Schedule IP_CT_NEW_REPLY definition for removal in
    nf_conntrack_common.h.

11) Simplify checksumming recalculation in nf_nat.

12) Add comments to the openvswitch conntrack code, from Jarno.

13) Update the CT state key only after successful nf_conntrack_in()
    invocation.

14) Find existing conntrack entry after upcall.

15) Handle NF_REPEAT case due to templates in nf_conntrack_in().

16) Call the conntrack helper functions once the conntrack has been
    confirmed.

17) And finally, add the NAT interface to OVS.

The batch closes with:

18) Cleanup to use spin_unlock_wait() instead of
    spin_lock()/spin_unlock(), from Nicholas Mc Guire.

You can pull these changes from:

  git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next.git

Thanks!

----------------------------------------------------------------

The following changes since commit 3b8377dca1fd1974d245b2a04a708fc434761c65:

  Merge branch 'variable-length-ll-headers' (2016-03-09 22:13:01 -0500)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next.git HEAD

for you to fetch changes up to e39365be031e37b229f745ea49db0b25e82436fa:

  netfilter: nf_conntrack: consolidate lock/unlock into unlock_wait (2016-03-15 01:10:42 +0100)

----------------------------------------------------------------
Arnd Bergmann (1):
      ipvs: handle ip_vs_fill_iph_skb_off failure

Florian Westphal (2):
      netfilter: nft_compat: check match/targetinfo attr size
      netfilter: x_tables: check for size overflow

Jarno Rajahalme (8):
      netfilter: Remove IP_CT_NEW_REPLY definition.
      netfilter: Allow calling into nat helper without skb_dst.
      openvswitch: Add commentary to conntrack.c
      openvswitch: Update the CT state key only after nf_conntrack_in().
      openvswitch: Find existing conntrack entry after upcall.
      openvswitch: Handle NF_REPEAT in conntrack action.
      openvswitch: Delay conntrack helper call for new connections.
      openvswitch: Interface with NAT.

Jozsef Kadlecsik (2):
      netfilter: ipset: Fix set:list type crash when flush/dump set in parallel
      netfilter: ipset: Check IPSET_ATTR_ETHER netlink attribute length

Julian Anastasov (2):
      ipvs: drop first packet to redirect conntrack
      ipvs: allow rescheduling after RST

Marco Angaroni (1):
      ipvs: correct initial offset of Call-ID header search in SIP persistence engine

Nicholas Mc Guire (1):
      netfilter: nf_conntrack: consolidate lock/unlock into unlock_wait

Pablo Neira Ayuso (2):
      Merge branch 'master' of git://blackhole.kfki.hu/nf
      Merge tag 'ipvs-fixes-for-v4.5' of https://git.kernel.org/.../horms/ipvs

Phil Turnbull (1):
      netfilter: nfnetlink_acct: validate NFACCT_FILTER parameters

 include/net/ip_vs.h                                |  17 +
 include/uapi/linux/netfilter/nf_conntrack_common.h |  12 +-
 include/uapi/linux/openvswitch.h                   |  49 ++
 net/ipv4/netfilter/nf_nat_l3proto_ipv4.c           |  30 +-
 net/ipv6/netfilter/nf_nat_l3proto_ipv6.c           |  30 +-
 net/netfilter/ipset/ip_set_bitmap_ipmac.c          |   2 +
 net/netfilter/ipset/ip_set_core.c                  |   3 +
 net/netfilter/ipset/ip_set_hash_mac.c              |   3 +-
 net/netfilter/ipset/ip_set_list_set.c              |  55 +-
 net/netfilter/ipvs/ip_vs_core.c                    |  38 +-
 net/netfilter/ipvs/ip_vs_pe_sip.c                  |   6 +-
 net/netfilter/nf_conntrack_core.c                  |   6 +-
 net/netfilter/nfnetlink_acct.c                     |   3 +
 net/netfilter/nft_compat.c                         |   6 +
 net/netfilter/x_tables.c                           |   3 +
 net/openvswitch/Kconfig                            |   3 +-
 net/openvswitch/conntrack.c                        | 660 +++++++++++++++++++--
 net/openvswitch/conntrack.h                        |   3 +-
 18 files changed, 795 insertions(+), 134 deletions(-)

[PATCH 01/18] netfilter: ipset: Fix set:list type crash when flush/dump set in parallel

[Pablo Neira Ayuso]

From: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>

Flushing/listing entries was not RCU safe, so parallel flush/dump
could lead to kernel crash. Bug reported by Deniz Eren.

Fixes netfilter bugzilla id #1050.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
---
 net/netfilter/ipset/ip_set_core.c     |  3 ++
 net/netfilter/ipset/ip_set_list_set.c | 55 ++++++++++++++++-------------------
 2 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 95db43f..7e6568c 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -985,6 +985,9 @@ static int ip_set_destroy(struct net *net, struct sock *ctnl,
 	if (unlikely(protocol_failed(attr)))
 		return -IPSET_ERR_PROTOCOL;
 
+	/* Must wait for flush to be really finished in list:set */
+	rcu_barrier();
+
 	/* Commands are serialized and references are
 	 * protected by the ip_set_ref_lock.
 	 * External systems (i.e. xt_set) must call
diff --git a/net/netfilter/ipset/ip_set_list_set.c b/net/netfilter/ipset/ip_set_list_set.c
index bbede95..24c6c19 100644
--- a/net/netfilter/ipset/ip_set_list_set.c
+++ b/net/netfilter/ipset/ip_set_list_set.c
@@ -30,6 +30,7 @@ MODULE_ALIAS("ip_set_list:set");
 struct set_elem {
 	struct rcu_head rcu;
 	struct list_head list;
+	struct ip_set *set;	/* Sigh, in order to cleanup reference */
 	ip_set_id_t id;
 } __aligned(__alignof__(u64));
 
@@ -151,30 +152,29 @@ list_set_kadt(struct ip_set *set, const struct sk_buff *skb,
 /* Userspace interfaces: we are protected by the nfnl mutex */
 
 static void
-__list_set_del(struct ip_set *set, struct set_elem *e)
+__list_set_del_rcu(struct rcu_head * rcu)
 {
+	struct set_elem *e = container_of(rcu, struct set_elem, rcu);
+	struct ip_set *set = e->set;
 	struct list_set *map = set->data;
 
 	ip_set_put_byindex(map->net, e->id);
-	/* We may call it, because we don't have a to be destroyed
-	 * extension which is used by the kernel.
-	 */
 	ip_set_ext_destroy(set, e);
-	kfree_rcu(e, rcu);
+	kfree(e);
 }
 
 static inline void
 list_set_del(struct ip_set *set, struct set_elem *e)
 {
 	list_del_rcu(&e->list);
-	__list_set_del(set, e);
+	call_rcu(&e->rcu, __list_set_del_rcu);
 }
 
 static inline void
-list_set_replace(struct ip_set *set, struct set_elem *e, struct set_elem *old)
+list_set_replace(struct set_elem *e, struct set_elem *old)
 {
 	list_replace_rcu(&old->list, &e->list);
-	__list_set_del(set, old);
+	call_rcu(&old->rcu, __list_set_del_rcu);
 }
 
 static void
@@ -244,9 +244,6 @@ list_set_uadd(struct ip_set *set, void *value, const struct ip_set_ext *ext,
 	struct set_elem *e, *n, *prev, *next;
 	bool flag_exist = flags & IPSET_FLAG_EXIST;
 
-	if (SET_WITH_TIMEOUT(set))
-		set_cleanup_entries(set);
-
 	/* Find where to add the new entry */
 	n = prev = next = NULL;
 	list_for_each_entry(e, &map->members, list) {
@@ -301,10 +298,11 @@ list_set_uadd(struct ip_set *set, void *value, const struct ip_set_ext *ext,
 	if (!e)
 		return -ENOMEM;
 	e->id = d->id;
+	e->set = set;
 	INIT_LIST_HEAD(&e->list);
 	list_set_init_extensions(set, ext, e);
 	if (n)
-		list_set_replace(set, e, n);
+		list_set_replace(e, n);
 	else if (next)
 		list_add_tail_rcu(&e->list, &next->list);
 	else if (prev)
@@ -431,6 +429,7 @@ list_set_destroy(struct ip_set *set)
 
 	if (SET_WITH_TIMEOUT(set))
 		del_timer_sync(&map->gc);
+
 	list_for_each_entry_safe(e, n, &map->members, list) {
 		list_del(&e->list);
 		ip_set_put_byindex(map->net, e->id);
@@ -450,8 +449,10 @@ list_set_head(struct ip_set *set, struct sk_buff *skb)
 	struct set_elem *e;
 	u32 n = 0;
 
-	list_for_each_entry(e, &map->members, list)
+	rcu_read_lock();
+	list_for_each_entry_rcu(e, &map->members, list)
 		n++;
+	rcu_read_unlock();
 
 	nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
 	if (!nested)
@@ -483,33 +484,25 @@ list_set_list(const struct ip_set *set,
 	atd = ipset_nest_start(skb, IPSET_ATTR_ADT);
 	if (!atd)
 		return -EMSGSIZE;
-	list_for_each_entry(e, &map->members, list) {
-		if (i == first)
-			break;
-		i++;
-	}
 
 	rcu_read_lock();
-	list_for_each_entry_from(e, &map->members, list) {
-		i++;
-		if (SET_WITH_TIMEOUT(set) &&
-		    ip_set_timeout_expired(ext_timeout(e, set)))
+	list_for_each_entry_rcu(e, &map->members, list) {
+		if (i < first ||
+		    (SET_WITH_TIMEOUT(set) &&
+		     ip_set_timeout_expired(ext_timeout(e, set)))) {
+			i++;
 			continue;
+		}
 		nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
-		if (!nested) {
-			if (i == first) {
-				nla_nest_cancel(skb, atd);
-				ret = -EMSGSIZE;
-				goto out;
-			}
+		if (!nested)
 			goto nla_put_failure;
-		}
 		if (nla_put_string(skb, IPSET_ATTR_NAME,
 				   ip_set_name_byindex(map->net, e->id)))
 			goto nla_put_failure;
 		if (ip_set_put_extensions(skb, set, e, true))
 			goto nla_put_failure;
 		ipset_nest_end(skb, nested);
+		i++;
 	}
 
 	ipset_nest_end(skb, atd);
@@ -520,10 +513,12 @@ list_set_list(const struct ip_set *set,
 nla_put_failure:
 	nla_nest_cancel(skb, nested);
 	if (unlikely(i == first)) {
+		nla_nest_cancel(skb, atd);
 		cb->args[IPSET_CB_ARG0] = 0;
 		ret = -EMSGSIZE;
+	} else {
+		cb->args[IPSET_CB_ARG0] = i;
 	}
-	cb->args[IPSET_CB_ARG0] = i - 1;
 	ipset_nest_end(skb, atd);
 out:
 	rcu_read_unlock();
-- 
2.1.4

[PATCH 02/18] netfilter: nfnetlink_acct: validate NFACCT_FILTER parameters

[Pablo Neira Ayuso]

From: Phil Turnbull <phil.turnbull@oracle.com>

nfacct_filter_alloc doesn't validate the NFACCT_FILTER_MASK and
NFACCT_FILTER_VALUE parameters which can trigger a NULL pointer
dereference. CAP_NET_ADMIN is required to trigger the bug.

Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nfnetlink_acct.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c
index 5274b04..4c2b4c0 100644
--- a/net/netfilter/nfnetlink_acct.c
+++ b/net/netfilter/nfnetlink_acct.c
@@ -242,6 +242,9 @@ nfacct_filter_alloc(const struct nlattr * const attr)
 	if (err < 0)
 		return ERR_PTR(err);
 
+	if (!tb[NFACCT_FILTER_MASK] || !tb[NFACCT_FILTER_VALUE])
+		return ERR_PTR(-EINVAL);
+
 	filter = kzalloc(sizeof(struct nfacct_filter), GFP_KERNEL);
 	if (!filter)
 		return ERR_PTR(-ENOMEM);
-- 
2.1.4

[PATCH 03/18] ipvs: handle ip_vs_fill_iph_skb_off failure

[Pablo Neira Ayuso]

From: Arnd Bergmann <arnd@arndb.de>

ip_vs_fill_iph_skb_off() may not find an IP header, and gcc has
determined that ip_vs_sip_fill_param() then incorrectly accesses
the protocol fields:

net/netfilter/ipvs/ip_vs_pe_sip.c: In function 'ip_vs_sip_fill_param':
net/netfilter/ipvs/ip_vs_pe_sip.c:76:5: error: 'iph.protocol' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  if (iph.protocol != IPPROTO_UDP)
     ^
net/netfilter/ipvs/ip_vs_pe_sip.c:81:10: error: 'iph.len' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  dataoff = iph.len + sizeof(struct udphdr);
          ^

This adds a check for the ip_vs_fill_iph_skb_off() return code
before looking at the ip header data returned from it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: b0e010c527de ("ipvs: replace ip_vs_fill_ip4hdr with ip_vs_fill_iph_skb_off")
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_pe_sip.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_pe_sip.c b/net/netfilter/ipvs/ip_vs_pe_sip.c
index 1b8d594..c4e9ca0 100644
--- a/net/netfilter/ipvs/ip_vs_pe_sip.c
+++ b/net/netfilter/ipvs/ip_vs_pe_sip.c
@@ -70,10 +70,10 @@ ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
 	const char *dptr;
 	int retc;
 
-	ip_vs_fill_iph_skb(p->af, skb, false, &iph);
+	retc = ip_vs_fill_iph_skb(p->af, skb, false, &iph);
 
 	/* Only useful with UDP */
-	if (iph.protocol != IPPROTO_UDP)
+	if (!retc || iph.protocol != IPPROTO_UDP)
 		return -EINVAL;
 	/* todo: IPv6 fragments:
 	 *       I think this only should be done for the first fragment. /HS
-- 
2.1.4

[PATCH 04/18] ipvs: drop first packet to redirect conntrack

[Pablo Neira Ayuso]

From: Julian Anastasov <ja@ssi.bg>

Jiri Bohac is reporting for a problem where the attempt
to reschedule existing connection to another real server
needs proper redirect for the conntrack used by the IPVS
connection. For example, when IPVS connection is created
to NAT-ed real server we alter the reply direction of
conntrack. If we later decide to select different real
server we can not alter again the conntrack. And if we
expire the old connection, the new connection is left
without conntrack.

So, the only way to redirect both the IPVS connection and
the Netfilter's conntrack is to drop the SYN packet that
hits existing connection, to wait for the next jiffie
to expire the old connection and its conntrack and to rely
on client's retransmission to create new connection as
usually.

Jiri Bohac provided a fix that drops all SYNs on rescheduling,
I extended his patch to do such drops only for connections
that use conntrack. Here is the original report from Jiri Bohac:

Since commit dc7b3eb900aa ("ipvs: Fix reuse connection if real server
is dead"), new connections to dead servers are redistributed
immediately to new servers.  The old connection is expired using
ip_vs_conn_expire_now() which sets the connection timer to expire
immediately.

However, before the timer callback, ip_vs_conn_expire(), is run
to clean the connection's conntrack entry, the new redistributed
connection may already be established and its conntrack removed
instead.

Fix this by dropping the first packet of the new connection
instead, like we do when the destination server is not available.
The timer will have deleted the old conntrack entry long before
the first packet of the new connection is retransmitted.

Fixes: dc7b3eb900aa ("ipvs: Fix reuse connection if real server is dead")
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 include/net/ip_vs.h             | 17 +++++++++++++++++
 net/netfilter/ipvs/ip_vs_core.c | 37 ++++++++++++++++++++++++++++---------
 2 files changed, 45 insertions(+), 9 deletions(-)

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index 0816c87..a6cc576 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -1588,6 +1588,23 @@ static inline void ip_vs_conn_drop_conntrack(struct ip_vs_conn *cp)
 }
 #endif /* CONFIG_IP_VS_NFCT */
 
+/* Really using conntrack? */
+static inline bool ip_vs_conn_uses_conntrack(struct ip_vs_conn *cp,
+					     struct sk_buff *skb)
+{
+#ifdef CONFIG_IP_VS_NFCT
+	enum ip_conntrack_info ctinfo;
+	struct nf_conn *ct;
+
+	if (!(cp->flags & IP_VS_CONN_F_NFCT))
+		return false;
+	ct = nf_ct_get(skb, &ctinfo);
+	if (ct && !nf_ct_is_untracked(ct))
+		return true;
+#endif
+	return false;
+}
+
 static inline int
 ip_vs_dest_conn_overhead(struct ip_vs_dest *dest)
 {
diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index f57b4dc..4da5600 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -1757,15 +1757,34 @@ ip_vs_in(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int
 	cp = pp->conn_in_get(ipvs, af, skb, &iph);
 
 	conn_reuse_mode = sysctl_conn_reuse_mode(ipvs);
-	if (conn_reuse_mode && !iph.fragoffs &&
-	    is_new_conn(skb, &iph) && cp &&
-	    ((unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest &&
-	      unlikely(!atomic_read(&cp->dest->weight))) ||
-	     unlikely(is_new_conn_expected(cp, conn_reuse_mode)))) {
-		if (!atomic_read(&cp->n_control))
-			ip_vs_conn_expire_now(cp);
-		__ip_vs_conn_put(cp);
-		cp = NULL;
+	if (conn_reuse_mode && !iph.fragoffs && is_new_conn(skb, &iph) && cp) {
+		bool uses_ct = false, resched = false;
+
+		if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest &&
+		    unlikely(!atomic_read(&cp->dest->weight))) {
+			resched = true;
+			uses_ct = ip_vs_conn_uses_conntrack(cp, skb);
+		} else if (is_new_conn_expected(cp, conn_reuse_mode)) {
+			uses_ct = ip_vs_conn_uses_conntrack(cp, skb);
+			if (!atomic_read(&cp->n_control)) {
+				resched = true;
+			} else {
+				/* Do not reschedule controlling connection
+				 * that uses conntrack while it is still
+				 * referenced by controlled connection(s).
+				 */
+				resched = !uses_ct;
+			}
+		}
+
+		if (resched) {
+			if (!atomic_read(&cp->n_control))
+				ip_vs_conn_expire_now(cp);
+			__ip_vs_conn_put(cp);
+			if (uses_ct)
+				return NF_DROP;
+			cp = NULL;
+		}
 	}
 
 	if (unlikely(!cp)) {
-- 
2.1.4

[PATCH 05/18] ipvs: allow rescheduling after RST

[Pablo Neira Ayuso]

From: Julian Anastasov <ja@ssi.bg>

"RFC 5961, 4.2. Mitigation" describes a mechanism to request
client to confirm with RST the restart of TCP connection
before resending its SYN. As result, IPVS can see SYNs for
existing connection in CLOSE state. Add check to allow
rescheduling in this state.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index 4da5600..b9a4082 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -1089,6 +1089,7 @@ static inline bool is_new_conn_expected(const struct ip_vs_conn *cp,
 	switch (cp->protocol) {
 	case IPPROTO_TCP:
 		return (cp->state == IP_VS_TCP_S_TIME_WAIT) ||
+		       (cp->state == IP_VS_TCP_S_CLOSE) ||
 			((conn_reuse_mode & 2) &&
 			 (cp->state == IP_VS_TCP_S_FIN_WAIT) &&
 			 (cp->flags & IP_VS_CONN_F_NOOUTPUT));
-- 
2.1.4

[PATCH 06/18] ipvs: correct initial offset of Call-ID header search in SIP persistence engine

[Pablo Neira Ayuso]

From: Marco Angaroni <marcoangaroni@gmail.com>

The IPVS SIP persistence engine is not able to parse the SIP header
"Call-ID" when such header is inserted in the first positions of
the SIP message.

When IPVS is configured with "--pe sip" option, like for example:
ipvsadm -A -u 1.2.3.4:5060 -s rr --pe sip -p 120 -o
some particular messages (see below for details) do not create entries
in the connection template table, which can be listed with:
ipvsadm -Lcn --persistent-conn

Problematic SIP messages are SIP responses having "Call-ID" header
positioned just after message first line:
SIP/2.0 200 OK
[Call-ID header here]
[rest of the headers]

When "Call-ID" header is positioned down (after a few other headers)
it is correctly recognized.

This is due to the data offset used in get_callid function call inside
ip_vs_pe_sip.c file: since dptr already points to the start of the
SIP message, the value of dataoff should be initially 0.
Otherwise the header is searched starting from some bytes after the
first character of the SIP message.

Fixes: 758ff0338722 ("IPVS: sip persistence engine")
Signed-off-by: Marco Angaroni <marcoangaroni@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_pe_sip.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_pe_sip.c b/net/netfilter/ipvs/ip_vs_pe_sip.c
index c4e9ca0..0a6eb5c 100644
--- a/net/netfilter/ipvs/ip_vs_pe_sip.c
+++ b/net/netfilter/ipvs/ip_vs_pe_sip.c
@@ -88,7 +88,7 @@ ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
 	dptr = skb->data + dataoff;
 	datalen = skb->len - dataoff;
 
-	if (get_callid(dptr, dataoff, datalen, &matchoff, &matchlen))
+	if (get_callid(dptr, 0, datalen, &matchoff, &matchlen))
 		return -EINVAL;
 
 	/* N.B: pe_data is only set on success,
-- 
2.1.4

[PATCH 07/18] netfilter: ipset: Check IPSET_ATTR_ETHER netlink attribute length

[Pablo Neira Ayuso]

From: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>

Julia Lawall pointed out that IPSET_ATTR_ETHER netlink attribute length
was not checked explicitly, just for the maximum possible size. Malicious
netlink clients could send shorter attribute and thus resulting a kernel
read after the buffer.

The patch adds the explicit length checkings.

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
---
 net/netfilter/ipset/ip_set_bitmap_ipmac.c | 2 ++
 net/netfilter/ipset/ip_set_hash_mac.c     | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/ipset/ip_set_bitmap_ipmac.c b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
index 29dde20..9a065f6 100644
--- a/net/netfilter/ipset/ip_set_bitmap_ipmac.c
+++ b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
@@ -267,6 +267,8 @@ bitmap_ipmac_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	e.id = ip_to_id(map, ip);
 	if (tb[IPSET_ATTR_ETHER]) {
+		if (nla_len(tb[IPSET_ATTR_ETHER]) != ETH_ALEN)
+			return -IPSET_ERR_PROTOCOL;
 		memcpy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]), ETH_ALEN);
 		e.add_mac = 1;
 	}
diff --git a/net/netfilter/ipset/ip_set_hash_mac.c b/net/netfilter/ipset/ip_set_hash_mac.c
index f1e7d2c..8f004ed 100644
--- a/net/netfilter/ipset/ip_set_hash_mac.c
+++ b/net/netfilter/ipset/ip_set_hash_mac.c
@@ -110,7 +110,8 @@ hash_mac4_uadt(struct ip_set *set, struct nlattr *tb[],
 	if (tb[IPSET_ATTR_LINENO])
 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 
-	if (unlikely(!tb[IPSET_ATTR_ETHER]))
+	if (unlikely(!tb[IPSET_ATTR_ETHER] ||
+		     nla_len(tb[IPSET_ATTR_ETHER]) != ETH_ALEN))
 		return -IPSET_ERR_PROTOCOL;
 
 	ret = ip_set_get_extensions(set, tb, &ext);
-- 
2.1.4

[PATCH 08/18] netfilter: nft_compat: check match/targetinfo attr size

[Pablo Neira Ayuso]

From: Florian Westphal <fw@strlen.de>

We copy according to ->target|matchsize, so check that the netlink attribute
(which can include padding and might be larger) contains enough data.

Reported-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_compat.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c
index 454841b..6228c42 100644
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -660,6 +660,9 @@ nft_match_select_ops(const struct nft_ctx *ctx,
 	if (IS_ERR(match))
 		return ERR_PTR(-ENOENT);
 
+	if (match->matchsize > nla_len(tb[NFTA_MATCH_INFO]))
+		return ERR_PTR(-EINVAL);
+
 	/* This is the first time we use this match, allocate operations */
 	nft_match = kzalloc(sizeof(struct nft_xt), GFP_KERNEL);
 	if (nft_match == NULL)
@@ -740,6 +743,9 @@ nft_target_select_ops(const struct nft_ctx *ctx,
 	if (IS_ERR(target))
 		return ERR_PTR(-ENOENT);
 
+	if (target->targetsize > nla_len(tb[NFTA_TARGET_INFO]))
+		return ERR_PTR(-EINVAL);
+
 	/* This is the first time we use this target, allocate operations */
 	nft_target = kzalloc(sizeof(struct nft_xt), GFP_KERNEL);
 	if (nft_target == NULL)
-- 
2.1.4

[PATCH 09/18] netfilter: x_tables: check for size overflow

[Pablo Neira Ayuso]

From: Florian Westphal <fw@strlen.de>

Ben Hawkes says:
 integer overflow in xt_alloc_table_info, which on 32-bit systems can
 lead to small structure allocation and a copy_from_user based heap
 corruption.

Reported-by: Ben Hawkes <hawkes@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/x_tables.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index d0cd2b9..582c9cf 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -659,6 +659,9 @@ struct xt_table_info *xt_alloc_table_info(unsigned int size)
 	struct xt_table_info *info = NULL;
 	size_t sz = sizeof(*info) + size;
 
+	if (sz < sizeof(*info))
+		return NULL;
+
 	/* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
 	if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
 		return NULL;
-- 
2.1.4

[PATCH 10/18] netfilter: Remove IP_CT_NEW_REPLY definition.

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

Remove the definition of IP_CT_NEW_REPLY from the kernel as it does
not make sense.  This allows the definition of IP_CT_NUMBER to be
simplified as well.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/netfilter/nf_conntrack_common.h | 12 +++++++++---
 net/openvswitch/conntrack.c                        |  2 --
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/include/uapi/linux/netfilter/nf_conntrack_common.h b/include/uapi/linux/netfilter/nf_conntrack_common.h
index 319f471..6d074d1 100644
--- a/include/uapi/linux/netfilter/nf_conntrack_common.h
+++ b/include/uapi/linux/netfilter/nf_conntrack_common.h
@@ -20,9 +20,15 @@ enum ip_conntrack_info {
 
 	IP_CT_ESTABLISHED_REPLY = IP_CT_ESTABLISHED + IP_CT_IS_REPLY,
 	IP_CT_RELATED_REPLY = IP_CT_RELATED + IP_CT_IS_REPLY,
-	IP_CT_NEW_REPLY = IP_CT_NEW + IP_CT_IS_REPLY,	
-	/* Number of distinct IP_CT types (no NEW in reply dirn). */
-	IP_CT_NUMBER = IP_CT_IS_REPLY * 2 - 1
+	/* No NEW in reply direction. */
+
+	/* Number of distinct IP_CT types. */
+	IP_CT_NUMBER,
+
+	/* only for userspace compatibility */
+#ifndef __KERNEL__
+	IP_CT_NEW_REPLY = IP_CT_NUMBER,
+#endif
 };
 
 #define NF_CT_STATE_INVALID_BIT			(1 << 0)
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index ee6ff8f..3045290 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -75,7 +75,6 @@ static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
 	switch (ctinfo) {
 	case IP_CT_ESTABLISHED_REPLY:
 	case IP_CT_RELATED_REPLY:
-	case IP_CT_NEW_REPLY:
 		ct_state |= OVS_CS_F_REPLY_DIR;
 		break;
 	default:
@@ -92,7 +91,6 @@ static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
 		ct_state |= OVS_CS_F_RELATED;
 		break;
 	case IP_CT_NEW:
-	case IP_CT_NEW_REPLY:
 		ct_state |= OVS_CS_F_NEW;
 		break;
 	default:
-- 
2.1.4

[PATCH 11/18] netfilter: Allow calling into nat helper without skb_dst.

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

NAT checksum recalculation code assumes existence of skb_dst, which
becomes a problem for a later patch in the series ("openvswitch:
Interface with NAT.").  Simplify this by removing the check on
skb_dst, as the checksum will be dealt with later in the stack.

Suggested-by: Pravin Shelar <pshelar@nicira.com>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv4/netfilter/nf_nat_l3proto_ipv4.c | 30 ++++++++----------------------
 net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 30 ++++++++----------------------
 2 files changed, 16 insertions(+), 44 deletions(-)

diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
index 61c7cc2..f8aad03 100644
--- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
@@ -127,29 +127,15 @@ static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb,
 				    u8 proto, void *data, __sum16 *check,
 				    int datalen, int oldlen)
 {
-	const struct iphdr *iph = ip_hdr(skb);
-	struct rtable *rt = skb_rtable(skb);
-
 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
-		if (!(rt->rt_flags & RTCF_LOCAL) &&
-		    (!skb->dev || skb->dev->features &
-		     (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) {
-			skb->ip_summed = CHECKSUM_PARTIAL;
-			skb->csum_start = skb_headroom(skb) +
-					  skb_network_offset(skb) +
-					  ip_hdrlen(skb);
-			skb->csum_offset = (void *)check - data;
-			*check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
-						    datalen, proto, 0);
-		} else {
-			*check = 0;
-			*check = csum_tcpudp_magic(iph->saddr, iph->daddr,
-						   datalen, proto,
-						   csum_partial(data, datalen,
-								0));
-			if (proto == IPPROTO_UDP && !*check)
-				*check = CSUM_MANGLED_0;
-		}
+		const struct iphdr *iph = ip_hdr(skb);
+
+		skb->ip_summed = CHECKSUM_PARTIAL;
+		skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) +
+			ip_hdrlen(skb);
+		skb->csum_offset = (void *)check - data;
+		*check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen,
+					    proto, 0);
 	} else
 		inet_proto_csum_replace2(check, skb,
 					 htons(oldlen), htons(datalen), true);
diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
index 6ce3099..e0be97e 100644
--- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
@@ -131,29 +131,15 @@ static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb,
 				    u8 proto, void *data, __sum16 *check,
 				    int datalen, int oldlen)
 {
-	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
-	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
-
 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
-		if (!(rt->rt6i_flags & RTF_LOCAL) &&
-		    (!skb->dev || skb->dev->features &
-		     (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))) {
-			skb->ip_summed = CHECKSUM_PARTIAL;
-			skb->csum_start = skb_headroom(skb) +
-					  skb_network_offset(skb) +
-					  (data - (void *)skb->data);
-			skb->csum_offset = (void *)check - data;
-			*check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
-						  datalen, proto, 0);
-		} else {
-			*check = 0;
-			*check = csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
-						 datalen, proto,
-						 csum_partial(data, datalen,
-							      0));
-			if (proto == IPPROTO_UDP && !*check)
-				*check = CSUM_MANGLED_0;
-		}
+		const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+
+		skb->ip_summed = CHECKSUM_PARTIAL;
+		skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) +
+			(data - (void *)skb->data);
+		skb->csum_offset = (void *)check - data;
+		*check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
+					  datalen, proto, 0);
 	} else
 		inet_proto_csum_replace2(check, skb,
 					 htons(oldlen), htons(datalen), true);
-- 
2.1.4

[PATCH 12/18] openvswitch: Add commentary to conntrack.c

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

This makes the code easier to understand and the following patches
more focused.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/openvswitch/conntrack.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 3045290..2c2bf07 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -152,8 +152,12 @@ static void ovs_ct_update_key(const struct sk_buff *skb,
 	ct = nf_ct_get(skb, &ctinfo);
 	if (ct) {
 		state = ovs_ct_get_state(ctinfo);
+		/* All unconfirmed entries are NEW connections. */
 		if (!nf_ct_is_confirmed(ct))
 			state |= OVS_CS_F_NEW;
+		/* OVS persists the related flag for the duration of the
+		 * connection.
+		 */
 		if (ct->master)
 			state |= OVS_CS_F_RELATED;
 		zone = nf_ct_zone(ct);
@@ -165,6 +169,9 @@ static void ovs_ct_update_key(const struct sk_buff *skb,
 	__ovs_ct_update_key(key, state, zone, ct);
 }
 
+/* This is called to initialize CT key fields possibly coming in from the local
+ * stack.
+ */
 void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
 {
 	ovs_ct_update_key(skb, NULL, key, false);
@@ -199,7 +206,6 @@ static int ovs_ct_set_mark(struct sk_buff *skb, struct sw_flow_key *key,
 	struct nf_conn *ct;
 	u32 new_mark;
 
-
 	/* The connection could be invalid, in which case set_mark is no-op. */
 	ct = nf_ct_get(skb, &ctinfo);
 	if (!ct)
@@ -375,6 +381,11 @@ static bool skb_nfct_cached(const struct net *net, const struct sk_buff *skb,
 	return true;
 }
 
+/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
+ * not done already.  Update key with new CT state.
+ * Note that if the packet is deemed invalid by conntrack, skb->nfct will be
+ * set to NULL and 0 will be returned.
+ */
 static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 			   const struct ovs_conntrack_info *info,
 			   struct sk_buff *skb)
@@ -418,6 +429,13 @@ static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 {
 	struct nf_conntrack_expect *exp;
 
+	/* If we pass an expected packet through nf_conntrack_in() the
+	 * expectation is typically removed, but the packet could still be
+	 * lost in upcall processing.  To prevent this from happening we
+	 * perform an explicit expectation lookup.  Expected connections are
+	 * always new, and will be passed through conntrack only when they are
+	 * committed, as it is OK to remove the expectation at that time.
+	 */
 	exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
 	if (exp) {
 		u8 state;
@@ -455,6 +473,7 @@ static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
 	err = __ovs_ct_lookup(net, key, info, skb);
 	if (err)
 		return err;
+	/* This is a no-op if the connection has already been confirmed. */
 	if (nf_conntrack_confirm(skb) != NF_ACCEPT)
 		return -EINVAL;
 
-- 
2.1.4

[PATCH 13/18] openvswitch: Update the CT state key only after nf_conntrack_in().

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

Only a successful nf_conntrack_in() call can effect a connection state
change, so it suffices to update the key only after the
nf_conntrack_in() returns.

This change is needed for the later NAT patches.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/openvswitch/conntrack.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 2c2bf07..a487bb3 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -382,7 +382,8 @@ static bool skb_nfct_cached(const struct net *net, const struct sk_buff *skb,
 }
 
 /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
- * not done already.  Update key with new CT state.
+ * not done already.  Update key with new CT state after passing the packet
+ * through conntrack.
  * Note that if the packet is deemed invalid by conntrack, skb->nfct will be
  * set to NULL and 0 will be returned.
  */
@@ -411,14 +412,14 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 				    skb) != NF_ACCEPT)
 			return -ENOENT;
 
+		ovs_ct_update_key(skb, info, key, true);
+
 		if (ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
 			WARN_ONCE(1, "helper rejected packet");
 			return -EINVAL;
 		}
 	}
 
-	ovs_ct_update_key(skb, info, key, true);
-
 	return 0;
 }
 
-- 
2.1.4

[PATCH 14/18] openvswitch: Find existing conntrack entry after upcall.

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

Add a new function ovs_ct_find_existing() to find an existing
conntrack entry for which this packet was already applied to.  This is
only to be called when there is evidence that the packet was already
tracked and committed, but we lost the ct reference due to an
userspace upcall.

ovs_ct_find_existing() is called from skb_nfct_cached(), which can now
hide the fact that the ct reference may have been lost due to an
upcall.  This allows ovs_ct_commit() to be simplified.

This patch is needed by later "openvswitch: Interface with NAT" patch,
as we need to be able to pass the packet through NAT using the
original ct reference also after the reference is lost after an
upcall.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/openvswitch/conntrack.c | 103 ++++++++++++++++++++++++++++++++++++++------
 1 file changed, 90 insertions(+), 13 deletions(-)

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index a487bb3..ae36fe2 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -356,14 +356,101 @@ ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone,
 	return __nf_ct_expect_find(net, zone, &tuple);
 }
 
+/* This replicates logic from nf_conntrack_core.c that is not exported. */
+static enum ip_conntrack_info
+ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h)
+{
+	const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
+
+	if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
+		return IP_CT_ESTABLISHED_REPLY;
+	/* Once we've had two way comms, always ESTABLISHED. */
+	if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status))
+		return IP_CT_ESTABLISHED;
+	if (test_bit(IPS_EXPECTED_BIT, &ct->status))
+		return IP_CT_RELATED;
+	return IP_CT_NEW;
+}
+
+/* Find an existing connection which this packet belongs to without
+ * re-attributing statistics or modifying the connection state.  This allows an
+ * skb->nfct lost due to an upcall to be recovered during actions execution.
+ *
+ * Must be called with rcu_read_lock.
+ *
+ * On success, populates skb->nfct and skb->nfctinfo, and returns the
+ * connection.  Returns NULL if there is no existing entry.
+ */
+static struct nf_conn *
+ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone,
+		     u8 l3num, struct sk_buff *skb)
+{
+	struct nf_conntrack_l3proto *l3proto;
+	struct nf_conntrack_l4proto *l4proto;
+	struct nf_conntrack_tuple tuple;
+	struct nf_conntrack_tuple_hash *h;
+	enum ip_conntrack_info ctinfo;
+	struct nf_conn *ct;
+	unsigned int dataoff;
+	u8 protonum;
+
+	l3proto = __nf_ct_l3proto_find(l3num);
+	if (!l3proto) {
+		pr_debug("ovs_ct_find_existing: Can't get l3proto\n");
+		return NULL;
+	}
+	if (l3proto->get_l4proto(skb, skb_network_offset(skb), &dataoff,
+				 &protonum) <= 0) {
+		pr_debug("ovs_ct_find_existing: Can't get protonum\n");
+		return NULL;
+	}
+	l4proto = __nf_ct_l4proto_find(l3num, protonum);
+	if (!l4proto) {
+		pr_debug("ovs_ct_find_existing: Can't get l4proto\n");
+		return NULL;
+	}
+	if (!nf_ct_get_tuple(skb, skb_network_offset(skb), dataoff, l3num,
+			     protonum, net, &tuple, l3proto, l4proto)) {
+		pr_debug("ovs_ct_find_existing: Can't get tuple\n");
+		return NULL;
+	}
+
+	/* look for tuple match */
+	h = nf_conntrack_find_get(net, zone, &tuple);
+	if (!h)
+		return NULL;   /* Not found. */
+
+	ct = nf_ct_tuplehash_to_ctrack(h);
+
+	ctinfo = ovs_ct_get_info(h);
+	if (ctinfo == IP_CT_NEW) {
+		/* This should not happen. */
+		WARN_ONCE(1, "ovs_ct_find_existing: new packet for %p\n", ct);
+	}
+	skb->nfct = &ct->ct_general;
+	skb->nfctinfo = ctinfo;
+	return ct;
+}
+
 /* Determine whether skb->nfct is equal to the result of conntrack lookup. */
-static bool skb_nfct_cached(const struct net *net, const struct sk_buff *skb,
-			    const struct ovs_conntrack_info *info)
+static bool skb_nfct_cached(struct net *net,
+			    const struct sw_flow_key *key,
+			    const struct ovs_conntrack_info *info,
+			    struct sk_buff *skb)
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct;
 
 	ct = nf_ct_get(skb, &ctinfo);
+	/* If no ct, check if we have evidence that an existing conntrack entry
+	 * might be found for this skb.  This happens when we lose a skb->nfct
+	 * due to an upcall.  If the connection was not confirmed, it is not
+	 * cached and needs to be run through conntrack again.
+	 */
+	if (!ct && key->ct.state & OVS_CS_F_TRACKED &&
+	    !(key->ct.state & OVS_CS_F_INVALID) &&
+	    key->ct.zone == info->zone.id)
+		ct = ovs_ct_find_existing(net, &info->zone, info->family, skb);
 	if (!ct)
 		return false;
 	if (!net_eq(net, read_pnet(&ct->ct_net)))
@@ -396,7 +483,7 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 	 * actually run the packet through conntrack twice unless it's for a
 	 * different zone.
 	 */
-	if (!skb_nfct_cached(net, skb, info)) {
+	if (!skb_nfct_cached(net, key, info, skb)) {
 		struct nf_conn *tmpl = info->ct;
 
 		/* Associate skb with specified zone. */
@@ -459,18 +546,8 @@ static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
 			 const struct ovs_conntrack_info *info,
 			 struct sk_buff *skb)
 {
-	u8 state;
 	int err;
 
-	state = key->ct.state;
-	if (key->ct.zone == info->zone.id &&
-	    ((state & OVS_CS_F_TRACKED) && !(state & OVS_CS_F_NEW))) {
-		/* Previous lookup has shown that this connection is already
-		 * tracked and committed. Skip committing.
-		 */
-		return 0;
-	}
-
 	err = __ovs_ct_lookup(net, key, info, skb);
 	if (err)
 		return err;
-- 
2.1.4

[PATCH 15/18] openvswitch: Handle NF_REPEAT in conntrack action.

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

Repeat the nf_conntrack_in() call when it returns NF_REPEAT.  This
avoids dropping a SYN packet re-opening an existing TCP connection.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/openvswitch/conntrack.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index ae36fe2..85256b3 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -485,6 +485,7 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 	 */
 	if (!skb_nfct_cached(net, key, info, skb)) {
 		struct nf_conn *tmpl = info->ct;
+		int err;
 
 		/* Associate skb with specified zone. */
 		if (tmpl) {
@@ -495,8 +496,13 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 			skb->nfctinfo = IP_CT_NEW;
 		}
 
-		if (nf_conntrack_in(net, info->family, NF_INET_PRE_ROUTING,
-				    skb) != NF_ACCEPT)
+		/* Repeat if requested, see nf_iterate(). */
+		do {
+			err = nf_conntrack_in(net, info->family,
+					      NF_INET_PRE_ROUTING, skb);
+		} while (err == NF_REPEAT);
+
+		if (err != NF_ACCEPT)
 			return -ENOENT;
 
 		ovs_ct_update_key(skb, info, key, true);
-- 
2.1.4

[PATCH 16/18] openvswitch: Delay conntrack helper call for new connections.

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

There is no need to help connections that are not confirmed, so we can
delay helping new connections to the time when they are confirmed.
This change is needed for NAT support, and having this as a separate
patch will make the following NAT patch a bit easier to review.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/openvswitch/conntrack.c | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 85256b3..f718b72 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -483,7 +483,11 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 	 * actually run the packet through conntrack twice unless it's for a
 	 * different zone.
 	 */
-	if (!skb_nfct_cached(net, key, info, skb)) {
+	bool cached = skb_nfct_cached(net, key, info, skb);
+	enum ip_conntrack_info ctinfo;
+	struct nf_conn *ct;
+
+	if (!cached) {
 		struct nf_conn *tmpl = info->ct;
 		int err;
 
@@ -506,11 +510,18 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 			return -ENOENT;
 
 		ovs_ct_update_key(skb, info, key, true);
+	}
 
-		if (ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
-			WARN_ONCE(1, "helper rejected packet");
-			return -EINVAL;
-		}
+	/* Call the helper only if:
+	 * - nf_conntrack_in() was executed above ("!cached") for a confirmed
+	 *   connection, or
+	 * - When committing an unconfirmed connection.
+	 */
+	ct = nf_ct_get(skb, &ctinfo);
+	if (ct && (nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
+	    ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
+		WARN_ONCE(1, "helper rejected packet");
+		return -EINVAL;
 	}
 
 	return 0;
-- 
2.1.4

[PATCH 17/18] openvswitch: Interface with NAT.

[Pablo Neira Ayuso]

From: Jarno Rajahalme <jarno@ovn.org>

Extend OVS conntrack interface to cover NAT.  New nested
OVS_CT_ATTR_NAT attribute may be used to include NAT with a CT action.
A bare OVS_CT_ATTR_NAT only mangles existing and expected connections.
If OVS_NAT_ATTR_SRC or OVS_NAT_ATTR_DST is included within the nested
attributes, new (non-committed/non-confirmed) connections are mangled
according to the rest of the nested attributes.

The corresponding OVS userspace patch series includes test cases (in
tests/system-traffic.at) that also serve as example uses.

This work extends on a branch by Thomas Graf at
https://github.com/tgraf/ovs/tree/nat.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/openvswitch.h |  49 ++++
 net/openvswitch/Kconfig          |   3 +-
 net/openvswitch/conntrack.c      | 524 +++++++++++++++++++++++++++++++++++++--
 net/openvswitch/conntrack.h      |   3 +-
 4 files changed, 551 insertions(+), 28 deletions(-)

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index a27222d..616d047 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -454,6 +454,14 @@ struct ovs_key_ct_labels {
 #define OVS_CS_F_REPLY_DIR         0x08 /* Flow is in the reply direction. */
 #define OVS_CS_F_INVALID           0x10 /* Could not track connection. */
 #define OVS_CS_F_TRACKED           0x20 /* Conntrack has occurred. */
+#define OVS_CS_F_SRC_NAT           0x40 /* Packet's source address/port was
+					 * mangled by NAT.
+					 */
+#define OVS_CS_F_DST_NAT           0x80 /* Packet's destination address/port
+					 * was mangled by NAT.
+					 */
+
+#define OVS_CS_F_NAT_MASK (OVS_CS_F_SRC_NAT | OVS_CS_F_DST_NAT)
 
 /**
  * enum ovs_flow_attr - attributes for %OVS_FLOW_* commands.
@@ -632,6 +640,8 @@ struct ovs_action_hash {
  * mask. For each bit set in the mask, the corresponding bit in the value is
  * copied to the connection tracking label field in the connection.
  * @OVS_CT_ATTR_HELPER: variable length string defining conntrack ALG.
+ * @OVS_CT_ATTR_NAT: Nested OVS_NAT_ATTR_* for performing L3 network address
+ * translation (NAT) on the packet.
  */
 enum ovs_ct_attr {
 	OVS_CT_ATTR_UNSPEC,
@@ -641,12 +651,51 @@ enum ovs_ct_attr {
 	OVS_CT_ATTR_LABELS,     /* labels to associate with this connection. */
 	OVS_CT_ATTR_HELPER,     /* netlink helper to assist detection of
 				   related connections. */
+	OVS_CT_ATTR_NAT,        /* Nested OVS_NAT_ATTR_* */
 	__OVS_CT_ATTR_MAX
 };
 
 #define OVS_CT_ATTR_MAX (__OVS_CT_ATTR_MAX - 1)
 
 /**
+ * enum ovs_nat_attr - Attributes for %OVS_CT_ATTR_NAT.
+ *
+ * @OVS_NAT_ATTR_SRC: Flag for Source NAT (mangle source address/port).
+ * @OVS_NAT_ATTR_DST: Flag for Destination NAT (mangle destination
+ * address/port).  Only one of (@OVS_NAT_ATTR_SRC, @OVS_NAT_ATTR_DST) may be
+ * specified.  Effective only for packets for ct_state NEW connections.
+ * Packets of committed connections are mangled by the NAT action according to
+ * the committed NAT type regardless of the flags specified.  As a corollary, a
+ * NAT action without a NAT type flag will only mangle packets of committed
+ * connections.  The following NAT attributes only apply for NEW
+ * (non-committed) connections, and they may be included only when the CT
+ * action has the @OVS_CT_ATTR_COMMIT flag and either @OVS_NAT_ATTR_SRC or
+ * @OVS_NAT_ATTR_DST is also included.
+ * @OVS_NAT_ATTR_IP_MIN: struct in_addr or struct in6_addr
+ * @OVS_NAT_ATTR_IP_MAX: struct in_addr or struct in6_addr
+ * @OVS_NAT_ATTR_PROTO_MIN: u16 L4 protocol specific lower boundary (port)
+ * @OVS_NAT_ATTR_PROTO_MAX: u16 L4 protocol specific upper boundary (port)
+ * @OVS_NAT_ATTR_PERSISTENT: Flag for persistent IP mapping across reboots
+ * @OVS_NAT_ATTR_PROTO_HASH: Flag for pseudo random L4 port mapping (MD5)
+ * @OVS_NAT_ATTR_PROTO_RANDOM: Flag for fully randomized L4 port mapping
+ */
+enum ovs_nat_attr {
+	OVS_NAT_ATTR_UNSPEC,
+	OVS_NAT_ATTR_SRC,
+	OVS_NAT_ATTR_DST,
+	OVS_NAT_ATTR_IP_MIN,
+	OVS_NAT_ATTR_IP_MAX,
+	OVS_NAT_ATTR_PROTO_MIN,
+	OVS_NAT_ATTR_PROTO_MAX,
+	OVS_NAT_ATTR_PERSISTENT,
+	OVS_NAT_ATTR_PROTO_HASH,
+	OVS_NAT_ATTR_PROTO_RANDOM,
+	__OVS_NAT_ATTR_MAX,
+};
+
+#define OVS_NAT_ATTR_MAX (__OVS_NAT_ATTR_MAX - 1)
+
+/**
  * enum ovs_action_attr - Action types.
  *
  * @OVS_ACTION_ATTR_OUTPUT: Output packet to port.
diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig
index cd5fd9d..234a733 100644
--- a/net/openvswitch/Kconfig
+++ b/net/openvswitch/Kconfig
@@ -6,7 +6,8 @@ config OPENVSWITCH
 	tristate "Open vSwitch"
 	depends on INET
 	depends on !NF_CONNTRACK || \
-		   (NF_CONNTRACK && (!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6))
+		   (NF_CONNTRACK && ((!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6) && \
+				     (!NF_NAT || NF_NAT)))
 	select LIBCRC32C
 	select MPLS
 	select NET_MPLS_GSO
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index f718b72..dc5eb29 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -13,21 +13,31 @@
 
 #include <linux/module.h>
 #include <linux/openvswitch.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/sctp.h>
 #include <net/ip.h>
 #include <net/netfilter/nf_conntrack_core.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_labels.h>
+#include <net/netfilter/nf_conntrack_seqadj.h>
 #include <net/netfilter/nf_conntrack_zones.h>
 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
 
+#ifdef CONFIG_NF_NAT_NEEDED
+#include <linux/netfilter/nf_nat.h>
+#include <net/netfilter/nf_nat_core.h>
+#include <net/netfilter/nf_nat_l3proto.h>
+#endif
+
 #include "datapath.h"
 #include "conntrack.h"
 #include "flow.h"
 #include "flow_netlink.h"
 
 struct ovs_ct_len_tbl {
-	size_t maxlen;
-	size_t minlen;
+	int maxlen;
+	int minlen;
 };
 
 /* Metadata mark for masked write to conntrack mark */
@@ -42,15 +52,25 @@ struct md_labels {
 	struct ovs_key_ct_labels mask;
 };
 
+enum ovs_ct_nat {
+	OVS_CT_NAT = 1 << 0,     /* NAT for committed connections only. */
+	OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */
+	OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */
+};
+
 /* Conntrack action context for execution. */
 struct ovs_conntrack_info {
 	struct nf_conntrack_helper *helper;
 	struct nf_conntrack_zone zone;
 	struct nf_conn *ct;
 	u8 commit : 1;
+	u8 nat : 3;                 /* enum ovs_ct_nat */
 	u16 family;
 	struct md_mark mark;
 	struct md_labels labels;
+#ifdef CONFIG_NF_NAT_NEEDED
+	struct nf_nat_range range;  /* Only present for SRC NAT and DST NAT. */
+#endif
 };
 
 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
@@ -137,12 +157,15 @@ static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
 	ovs_ct_get_labels(ct, &key->ct.labels);
 }
 
-/* Update 'key' based on skb->nfct. If 'post_ct' is true, then OVS has
- * previously sent the packet to conntrack via the ct action.
+/* Update 'key' based on skb->nfct.  If 'post_ct' is true, then OVS has
+ * previously sent the packet to conntrack via the ct action.  If
+ * 'keep_nat_flags' is true, the existing NAT flags retained, else they are
+ * initialized from the connection status.
  */
 static void ovs_ct_update_key(const struct sk_buff *skb,
 			      const struct ovs_conntrack_info *info,
-			      struct sw_flow_key *key, bool post_ct)
+			      struct sw_flow_key *key, bool post_ct,
+			      bool keep_nat_flags)
 {
 	const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
 	enum ip_conntrack_info ctinfo;
@@ -160,6 +183,14 @@ static void ovs_ct_update_key(const struct sk_buff *skb,
 		 */
 		if (ct->master)
 			state |= OVS_CS_F_RELATED;
+		if (keep_nat_flags) {
+			state |= key->ct.state & OVS_CS_F_NAT_MASK;
+		} else {
+			if (ct->status & IPS_SRC_NAT)
+				state |= OVS_CS_F_SRC_NAT;
+			if (ct->status & IPS_DST_NAT)
+				state |= OVS_CS_F_DST_NAT;
+		}
 		zone = nf_ct_zone(ct);
 	} else if (post_ct) {
 		state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
@@ -174,7 +205,7 @@ static void ovs_ct_update_key(const struct sk_buff *skb,
  */
 void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
 {
-	ovs_ct_update_key(skb, NULL, key, false);
+	ovs_ct_update_key(skb, NULL, key, false, false);
 }
 
 int ovs_ct_put_key(const struct sw_flow_key *key, struct sk_buff *skb)
@@ -263,6 +294,7 @@ static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
 	enum ip_conntrack_info ctinfo;
 	unsigned int protoff;
 	struct nf_conn *ct;
+	int err;
 
 	ct = nf_ct_get(skb, &ctinfo);
 	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
@@ -299,7 +331,18 @@ static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
 		return NF_DROP;
 	}
 
-	return helper->help(skb, protoff, ct, ctinfo);
+	err = helper->help(skb, protoff, ct, ctinfo);
+	if (err != NF_ACCEPT)
+		return err;
+
+	/* Adjust seqs after helper.  This is needed due to some helpers (e.g.,
+	 * FTP with NAT) adusting the TCP payload size when mangling IP
+	 * addresses and/or port numbers in the text-based control connection.
+	 */
+	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
+	    !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
+		return NF_DROP;
+	return NF_ACCEPT;
 }
 
 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
@@ -468,6 +511,200 @@ static bool skb_nfct_cached(struct net *net,
 	return true;
 }
 
+#ifdef CONFIG_NF_NAT_NEEDED
+/* Modelled after nf_nat_ipv[46]_fn().
+ * range is only used for new, uninitialized NAT state.
+ * Returns either NF_ACCEPT or NF_DROP.
+ */
+static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
+			      enum ip_conntrack_info ctinfo,
+			      const struct nf_nat_range *range,
+			      enum nf_nat_manip_type maniptype)
+{
+	int hooknum, nh_off, err = NF_ACCEPT;
+
+	nh_off = skb_network_offset(skb);
+	skb_pull(skb, nh_off);
+
+	/* See HOOK2MANIP(). */
+	if (maniptype == NF_NAT_MANIP_SRC)
+		hooknum = NF_INET_LOCAL_IN; /* Source NAT */
+	else
+		hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
+
+	switch (ctinfo) {
+	case IP_CT_RELATED:
+	case IP_CT_RELATED_REPLY:
+		if (skb->protocol == htons(ETH_P_IP) &&
+		    ip_hdr(skb)->protocol == IPPROTO_ICMP) {
+			if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
+							   hooknum))
+				err = NF_DROP;
+			goto push;
+#if IS_ENABLED(CONFIG_NF_NAT_IPV6)
+		} else if (skb->protocol == htons(ETH_P_IPV6)) {
+			__be16 frag_off;
+			u8 nexthdr = ipv6_hdr(skb)->nexthdr;
+			int hdrlen = ipv6_skip_exthdr(skb,
+						      sizeof(struct ipv6hdr),
+						      &nexthdr, &frag_off);
+
+			if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
+				if (!nf_nat_icmpv6_reply_translation(skb, ct,
+								     ctinfo,
+								     hooknum,
+								     hdrlen))
+					err = NF_DROP;
+				goto push;
+			}
+#endif
+		}
+		/* Non-ICMP, fall thru to initialize if needed. */
+	case IP_CT_NEW:
+		/* Seen it before?  This can happen for loopback, retrans,
+		 * or local packets.
+		 */
+		if (!nf_nat_initialized(ct, maniptype)) {
+			/* Initialize according to the NAT action. */
+			err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
+				/* Action is set up to establish a new
+				 * mapping.
+				 */
+				? nf_nat_setup_info(ct, range, maniptype)
+				: nf_nat_alloc_null_binding(ct, hooknum);
+			if (err != NF_ACCEPT)
+				goto push;
+		}
+		break;
+
+	case IP_CT_ESTABLISHED:
+	case IP_CT_ESTABLISHED_REPLY:
+		break;
+
+	default:
+		err = NF_DROP;
+		goto push;
+	}
+
+	err = nf_nat_packet(ct, ctinfo, hooknum, skb);
+push:
+	skb_push(skb, nh_off);
+
+	return err;
+}
+
+static void ovs_nat_update_key(struct sw_flow_key *key,
+			       const struct sk_buff *skb,
+			       enum nf_nat_manip_type maniptype)
+{
+	if (maniptype == NF_NAT_MANIP_SRC) {
+		__be16 src;
+
+		key->ct.state |= OVS_CS_F_SRC_NAT;
+		if (key->eth.type == htons(ETH_P_IP))
+			key->ipv4.addr.src = ip_hdr(skb)->saddr;
+		else if (key->eth.type == htons(ETH_P_IPV6))
+			memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
+			       sizeof(key->ipv6.addr.src));
+		else
+			return;
+
+		if (key->ip.proto == IPPROTO_UDP)
+			src = udp_hdr(skb)->source;
+		else if (key->ip.proto == IPPROTO_TCP)
+			src = tcp_hdr(skb)->source;
+		else if (key->ip.proto == IPPROTO_SCTP)
+			src = sctp_hdr(skb)->source;
+		else
+			return;
+
+		key->tp.src = src;
+	} else {
+		__be16 dst;
+
+		key->ct.state |= OVS_CS_F_DST_NAT;
+		if (key->eth.type == htons(ETH_P_IP))
+			key->ipv4.addr.dst = ip_hdr(skb)->daddr;
+		else if (key->eth.type == htons(ETH_P_IPV6))
+			memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
+			       sizeof(key->ipv6.addr.dst));
+		else
+			return;
+
+		if (key->ip.proto == IPPROTO_UDP)
+			dst = udp_hdr(skb)->dest;
+		else if (key->ip.proto == IPPROTO_TCP)
+			dst = tcp_hdr(skb)->dest;
+		else if (key->ip.proto == IPPROTO_SCTP)
+			dst = sctp_hdr(skb)->dest;
+		else
+			return;
+
+		key->tp.dst = dst;
+	}
+}
+
+/* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
+static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
+		      const struct ovs_conntrack_info *info,
+		      struct sk_buff *skb, struct nf_conn *ct,
+		      enum ip_conntrack_info ctinfo)
+{
+	enum nf_nat_manip_type maniptype;
+	int err;
+
+	if (nf_ct_is_untracked(ct)) {
+		/* A NAT action may only be performed on tracked packets. */
+		return NF_ACCEPT;
+	}
+
+	/* Add NAT extension if not confirmed yet. */
+	if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
+		return NF_ACCEPT;   /* Can't NAT. */
+
+	/* Determine NAT type.
+	 * Check if the NAT type can be deduced from the tracked connection.
+	 * Make sure expected traffic is NATted only when committing.
+	 */
+	if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
+	    ct->status & IPS_NAT_MASK &&
+	    (!(ct->status & IPS_EXPECTED_BIT) || info->commit)) {
+		/* NAT an established or related connection like before. */
+		if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
+			/* This is the REPLY direction for a connection
+			 * for which NAT was applied in the forward
+			 * direction.  Do the reverse NAT.
+			 */
+			maniptype = ct->status & IPS_SRC_NAT
+				? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
+		else
+			maniptype = ct->status & IPS_SRC_NAT
+				? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
+	} else if (info->nat & OVS_CT_SRC_NAT) {
+		maniptype = NF_NAT_MANIP_SRC;
+	} else if (info->nat & OVS_CT_DST_NAT) {
+		maniptype = NF_NAT_MANIP_DST;
+	} else {
+		return NF_ACCEPT; /* Connection is not NATed. */
+	}
+	err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
+
+	/* Mark NAT done if successful and update the flow key. */
+	if (err == NF_ACCEPT)
+		ovs_nat_update_key(key, skb, maniptype);
+
+	return err;
+}
+#else /* !CONFIG_NF_NAT_NEEDED */
+static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
+		      const struct ovs_conntrack_info *info,
+		      struct sk_buff *skb, struct nf_conn *ct,
+		      enum ip_conntrack_info ctinfo)
+{
+	return NF_ACCEPT;
+}
+#endif
+
 /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
  * not done already.  Update key with new CT state after passing the packet
  * through conntrack.
@@ -509,19 +746,43 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 		if (err != NF_ACCEPT)
 			return -ENOENT;
 
-		ovs_ct_update_key(skb, info, key, true);
+		/* Clear CT state NAT flags to mark that we have not yet done
+		 * NAT after the nf_conntrack_in() call.  We can actually clear
+		 * the whole state, as it will be re-initialized below.
+		 */
+		key->ct.state = 0;
+
+		/* Update the key, but keep the NAT flags. */
+		ovs_ct_update_key(skb, info, key, true, true);
 	}
 
-	/* Call the helper only if:
-	 * - nf_conntrack_in() was executed above ("!cached") for a confirmed
-	 *   connection, or
-	 * - When committing an unconfirmed connection.
-	 */
 	ct = nf_ct_get(skb, &ctinfo);
-	if (ct && (nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
-	    ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
-		WARN_ONCE(1, "helper rejected packet");
-		return -EINVAL;
+	if (ct) {
+		/* Packets starting a new connection must be NATted before the
+		 * helper, so that the helper knows about the NAT.  We enforce
+		 * this by delaying both NAT and helper calls for unconfirmed
+		 * connections until the committing CT action.  For later
+		 * packets NAT and Helper may be called in either order.
+		 *
+		 * NAT will be done only if the CT action has NAT, and only
+		 * once per packet (per zone), as guarded by the NAT bits in
+		 * the key->ct.state.
+		 */
+		if (info->nat && !(key->ct.state & OVS_CS_F_NAT_MASK) &&
+		    (nf_ct_is_confirmed(ct) || info->commit) &&
+		    ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
+			return -EINVAL;
+		}
+
+		/* Call the helper only if:
+		 * - nf_conntrack_in() was executed above ("!cached") for a
+		 *   confirmed connection, or
+		 * - When committing an unconfirmed connection.
+		 */
+		if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
+		    ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
+			return -EINVAL;
+		}
 	}
 
 	return 0;
@@ -545,15 +806,13 @@ static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 	if (exp) {
 		u8 state;
 
+		/* NOTE: New connections are NATted and Helped only when
+		 * committed, so we are not calling into NAT here.
+		 */
 		state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
 		__ovs_ct_update_key(key, state, &info->zone, exp->master);
-	} else {
-		int err;
-
-		err = __ovs_ct_lookup(net, key, info, skb);
-		if (err)
-			return err;
-	}
+	} else
+		return __ovs_ct_lookup(net, key, info, skb);
 
 	return 0;
 }
@@ -653,6 +912,135 @@ static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
 	return 0;
 }
 
+#ifdef CONFIG_NF_NAT_NEEDED
+static int parse_nat(const struct nlattr *attr,
+		     struct ovs_conntrack_info *info, bool log)
+{
+	struct nlattr *a;
+	int rem;
+	bool have_ip_max = false;
+	bool have_proto_max = false;
+	bool ip_vers = (info->family == NFPROTO_IPV6);
+
+	nla_for_each_nested(a, attr, rem) {
+		static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
+			[OVS_NAT_ATTR_SRC] = {0, 0},
+			[OVS_NAT_ATTR_DST] = {0, 0},
+			[OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
+						 sizeof(struct in6_addr)},
+			[OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
+						 sizeof(struct in6_addr)},
+			[OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
+			[OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
+			[OVS_NAT_ATTR_PERSISTENT] = {0, 0},
+			[OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
+			[OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
+		};
+		int type = nla_type(a);
+
+		if (type > OVS_NAT_ATTR_MAX) {
+			OVS_NLERR(log,
+				  "Unknown NAT attribute (type=%d, max=%d).\n",
+				  type, OVS_NAT_ATTR_MAX);
+			return -EINVAL;
+		}
+
+		if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
+			OVS_NLERR(log,
+				  "NAT attribute type %d has unexpected length (%d != %d).\n",
+				  type, nla_len(a),
+				  ovs_nat_attr_lens[type][ip_vers]);
+			return -EINVAL;
+		}
+
+		switch (type) {
+		case OVS_NAT_ATTR_SRC:
+		case OVS_NAT_ATTR_DST:
+			if (info->nat) {
+				OVS_NLERR(log,
+					  "Only one type of NAT may be specified.\n"
+					  );
+				return -ERANGE;
+			}
+			info->nat |= OVS_CT_NAT;
+			info->nat |= ((type == OVS_NAT_ATTR_SRC)
+					? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
+			break;
+
+		case OVS_NAT_ATTR_IP_MIN:
+			nla_memcpy(&info->range.min_addr, a, nla_len(a));
+			info->range.flags |= NF_NAT_RANGE_MAP_IPS;
+			break;
+
+		case OVS_NAT_ATTR_IP_MAX:
+			have_ip_max = true;
+			nla_memcpy(&info->range.max_addr, a,
+				   sizeof(info->range.max_addr));
+			info->range.flags |= NF_NAT_RANGE_MAP_IPS;
+			break;
+
+		case OVS_NAT_ATTR_PROTO_MIN:
+			info->range.min_proto.all = htons(nla_get_u16(a));
+			info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
+			break;
+
+		case OVS_NAT_ATTR_PROTO_MAX:
+			have_proto_max = true;
+			info->range.max_proto.all = htons(nla_get_u16(a));
+			info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
+			break;
+
+		case OVS_NAT_ATTR_PERSISTENT:
+			info->range.flags |= NF_NAT_RANGE_PERSISTENT;
+			break;
+
+		case OVS_NAT_ATTR_PROTO_HASH:
+			info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
+			break;
+
+		case OVS_NAT_ATTR_PROTO_RANDOM:
+			info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
+			break;
+
+		default:
+			OVS_NLERR(log, "Unknown nat attribute (%d).\n", type);
+			return -EINVAL;
+		}
+	}
+
+	if (rem > 0) {
+		OVS_NLERR(log, "NAT attribute has %d unknown bytes.\n", rem);
+		return -EINVAL;
+	}
+	if (!info->nat) {
+		/* Do not allow flags if no type is given. */
+		if (info->range.flags) {
+			OVS_NLERR(log,
+				  "NAT flags may be given only when NAT range (SRC or DST) is also specified.\n"
+				  );
+			return -EINVAL;
+		}
+		info->nat = OVS_CT_NAT;   /* NAT existing connections. */
+	} else if (!info->commit) {
+		OVS_NLERR(log,
+			  "NAT attributes may be specified only when CT COMMIT flag is also specified.\n"
+			  );
+		return -EINVAL;
+	}
+	/* Allow missing IP_MAX. */
+	if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
+		memcpy(&info->range.max_addr, &info->range.min_addr,
+		       sizeof(info->range.max_addr));
+	}
+	/* Allow missing PROTO_MAX. */
+	if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
+	    !have_proto_max) {
+		info->range.max_proto.all = info->range.min_proto.all;
+	}
+	return 0;
+}
+#endif
+
 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
 	[OVS_CT_ATTR_COMMIT]	= { .minlen = 0, .maxlen = 0 },
 	[OVS_CT_ATTR_ZONE]	= { .minlen = sizeof(u16),
@@ -662,7 +1050,11 @@ static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
 	[OVS_CT_ATTR_LABELS]	= { .minlen = sizeof(struct md_labels),
 				    .maxlen = sizeof(struct md_labels) },
 	[OVS_CT_ATTR_HELPER]	= { .minlen = 1,
-				    .maxlen = NF_CT_HELPER_NAME_LEN }
+				    .maxlen = NF_CT_HELPER_NAME_LEN },
+#ifdef CONFIG_NF_NAT_NEEDED
+	/* NAT length is checked when parsing the nested attributes. */
+	[OVS_CT_ATTR_NAT]	= { .minlen = 0, .maxlen = INT_MAX },
+#endif
 };
 
 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
@@ -729,6 +1121,15 @@ static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
 				return -EINVAL;
 			}
 			break;
+#ifdef CONFIG_NF_NAT_NEEDED
+		case OVS_CT_ATTR_NAT: {
+			int err = parse_nat(a, info, log);
+
+			if (err)
+				return err;
+			break;
+		}
+#endif
 		default:
 			OVS_NLERR(log, "Unknown conntrack attr (%d)",
 				  type);
@@ -816,6 +1217,74 @@ err_free_ct:
 	return err;
 }
 
+#ifdef CONFIG_NF_NAT_NEEDED
+static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
+			       struct sk_buff *skb)
+{
+	struct nlattr *start;
+
+	start = nla_nest_start(skb, OVS_CT_ATTR_NAT);
+	if (!start)
+		return false;
+
+	if (info->nat & OVS_CT_SRC_NAT) {
+		if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
+			return false;
+	} else if (info->nat & OVS_CT_DST_NAT) {
+		if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
+			return false;
+	} else {
+		goto out;
+	}
+
+	if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
+		if (info->family == NFPROTO_IPV4) {
+			if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
+					    info->range.min_addr.ip) ||
+			    (info->range.max_addr.ip
+			     != info->range.min_addr.ip &&
+			     (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
+					      info->range.max_addr.ip))))
+				return false;
+#if IS_ENABLED(CONFIG_NF_NAT_IPV6)
+		} else if (info->family == NFPROTO_IPV6) {
+			if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
+					     &info->range.min_addr.in6) ||
+			    (memcmp(&info->range.max_addr.in6,
+				    &info->range.min_addr.in6,
+				    sizeof(info->range.max_addr.in6)) &&
+			     (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
+					       &info->range.max_addr.in6))))
+				return false;
+#endif
+		} else {
+			return false;
+		}
+	}
+	if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
+	    (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
+			 ntohs(info->range.min_proto.all)) ||
+	     (info->range.max_proto.all != info->range.min_proto.all &&
+	      nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
+			  ntohs(info->range.max_proto.all)))))
+		return false;
+
+	if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
+	    nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
+		return false;
+	if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
+	    nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
+		return false;
+	if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
+	    nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
+		return false;
+out:
+	nla_nest_end(skb, start);
+
+	return true;
+}
+#endif
+
 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
 			  struct sk_buff *skb)
 {
@@ -844,7 +1313,10 @@ int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
 				   ct_info->helper->name))
 			return -EMSGSIZE;
 	}
-
+#ifdef CONFIG_NF_NAT_NEEDED
+	if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
+		return -EMSGSIZE;
+#endif
 	nla_nest_end(skb, start);
 
 	return 0;
diff --git a/net/openvswitch/conntrack.h b/net/openvswitch/conntrack.h
index a7544f4..8f6230b 100644
--- a/net/openvswitch/conntrack.h
+++ b/net/openvswitch/conntrack.h
@@ -37,7 +37,8 @@ void ovs_ct_free_action(const struct nlattr *a);
 
 #define CT_SUPPORTED_MASK (OVS_CS_F_NEW | OVS_CS_F_ESTABLISHED | \
 			   OVS_CS_F_RELATED | OVS_CS_F_REPLY_DIR | \
-			   OVS_CS_F_INVALID | OVS_CS_F_TRACKED)
+			   OVS_CS_F_INVALID | OVS_CS_F_TRACKED | \
+			   OVS_CS_F_SRC_NAT | OVS_CS_F_DST_NAT)
 #else
 #include <linux/errno.h>
 
-- 
2.1.4

[PATCH 18/18] netfilter: nf_conntrack: consolidate lock/unlock into unlock_wait

[Pablo Neira Ayuso]

From: Nicholas Mc Guire <hofrat@osadl.org>

The spin_lock()/spin_unlock() is synchronizing on the
nf_conntrack_locks_all_lock which is equivalent to
spin_unlock_wait() but the later should be more efficient.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_conntrack_core.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index f60b4fd..afde5f5 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -74,8 +74,7 @@ void nf_conntrack_lock(spinlock_t *lock) __acquires(lock)
 	spin_lock(lock);
 	while (unlikely(nf_conntrack_locks_all)) {
 		spin_unlock(lock);
-		spin_lock(&nf_conntrack_locks_all_lock);
-		spin_unlock(&nf_conntrack_locks_all_lock);
+		spin_unlock_wait(&nf_conntrack_locks_all_lock);
 		spin_lock(lock);
 	}
 }
@@ -121,8 +120,7 @@ static void nf_conntrack_all_lock(void)
 	nf_conntrack_locks_all = true;
 
 	for (i = 0; i < CONNTRACK_LOCKS; i++) {
-		spin_lock(&nf_conntrack_locks[i]);
-		spin_unlock(&nf_conntrack_locks[i]);
+		spin_unlock_wait(&nf_conntrack_locks[i]);
 	}
 }
 
-- 
2.1.4

Re: [PATCH 00/18] Netfilter/IPVS/OVS updates for net-next

[David Miller]

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 15 Mar 2016 02:27:44 +0100

> The following patchset contains Netfilter/IPVS fixes and OVS NAT
> support, more specifically this batch is composed of:
 ...
> You can pull these changes from:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next.git

Pulled, thanks Pablo.