[PATCH 0/5 net-next v5] VXLAN Group Policy Extension

[PATCH 0/5 net-next v5] VXLAN Group Policy Extension

[Thomas Graf]

Implements supports for the Group Policy VXLAN extension [0] to provide
a lightweight and simple security label mechanism across network peers
based on VXLAN. The security context and associated metadata is mapped
to/from skb->mark. This allows further mapping to a SELinux context
using SECMARK, to implement ACLs directly with nftables, iptables, OVS,
tc, etc.

The extension is disabled by default and should be run on a distinct
port in mixed Linux VXLAN VTEP environments. Liberal VXLAN VTEPs
which ignore unknown reserved bits will be able to receive VXLAN-GBP
frames.

Simple usage example:

10.1.1.1:
   # ip link add vxlan0 type vxlan id 10 remote 10.1.1.2 gbp
   # iptables -I OUTPUT -m owner --uid-owner 101 -j MARK --set-mark 0x200

10.1.1.2:
   # ip link add vxlan0 type vxlan id 10 remote 10.1.1.1 gbp
   # iptables -I INPUT -m mark --mark 0x200 -j DROP

iproute2 [1] and OVS [2] support will be provided in separate patches.

[0] https://tools.ietf.org/html/draft-smith-vxlan-group-policy
[1] https://github.com/tgraf/iproute2/tree/vxlan-gbp
[2] https://github.com/tgraf/ovs/tree/vxlan-gbp

Thomas Graf (5):
  vxlan: Group Policy extension
  vxlan: Only bind to sockets with correct extensions enabled
  openvswitch: Rename GENEVE_TUN_OPTS() to TUN_METADATA_OPTS()
  openvswitch: Allow for any level of nesting in flow attributes
  openvswitch: Support VXLAN Group Policy extension

 drivers/net/vxlan.c              | 125 +++++++++++++----
 include/net/ip_tunnels.h         |   5 +-
 include/net/vxlan.h              |  83 +++++++++++-
 include/uapi/linux/if_link.h     |   1 +
 include/uapi/linux/openvswitch.h |  11 ++
 net/openvswitch/flow.c           |   2 +-
 net/openvswitch/flow.h           |  14 +-
 net/openvswitch/flow_netlink.c   | 286 ++++++++++++++++++++++++++-------------
 net/openvswitch/vport-geneve.c   |  15 +-
 net/openvswitch/vport-vxlan.c    |  91 ++++++++++++-
 net/openvswitch/vport-vxlan.h    |  11 ++
 11 files changed, 500 insertions(+), 144 deletions(-)
 create mode 100644 net/openvswitch/vport-vxlan.h

-- 
1.9.3

[PATCH 1/5] vxlan: Group Policy extension

[Thomas Graf]

Implements supports for the Group Policy VXLAN extension [0] to provide
a lightweight and simple security label mechanism across network peers
based on VXLAN. The security context and associated metadata is mapped
to/from skb->mark. This allows further mapping to a SELinux context
using SECMARK, to implement ACLs directly with nftables, iptables, OVS,
tc, etc.

The group membership is defined by the lower 16 bits of skb->mark, the
upper 16 bits are used for flags.

SELinux allows to manage label to secure local resources. However,
distributed applications require ACLs to implemented across hosts. This
is typically achieved by matching on L2-L4 fields to identify the
original sending host and process on the receiver. On top of that,
netlabel and specifically CIPSO [1] allow to map security contexts to
universal labels.  However, netlabel and CIPSO are relatively complex.
This patch provides a lightweight alternative for overlay network
environments with a trusted underlay. No additional control protocol
is required.

           Host 1:                       Host 2:

      Group A        Group B        Group B     Group A
      +-----+   +-------------+    +-------+   +-----+
      | lxc |   | SELinux CTX |    | httpd |   | VM  |
      +--+--+   +--+----------+    +---+---+   +--+--+
	  \---+---/                     \----+---/
	      |                              |
	  +---+---+                      +---+---+
	  | vxlan |                      | vxlan |
	  +---+---+                      +---+---+
	      +------------------------------+

Backwards compatibility:
A VXLAN-GBP socket can receive standard VXLAN frames and will assign
the default group 0x0000 to such frames. A Linux VXLAN socket will
drop VXLAN-GBP  frames. The extension is therefore disabled by default
and needs to be specifically enabled:

   ip link add [...] type vxlan [...] gbp

In a mixed environment with VXLAN and VXLAN-GBP sockets, the GBP socket
must run on a separate port number.

Examples:
 iptables:
  host1# iptables -I OUTPUT -m owner --uid-owner 101 -j MARK --set-mark 0x200
  host2# iptables -I INPUT -m mark --mark 0x200 -j DROP

 OVS:
  # ovs-ofctl add-flow br0 'in_port=1,actions=load:0x200->NXM_NX_TUN_GBP_ID[],NORMAL'
  # ovs-ofctl add-flow br0 'in_port=2,tun_gbp_id=0x200,actions=drop'

[0] https://tools.ietf.org/html/draft-smith-vxlan-group-policy
[1] http://lwn.net/Articles/204905/

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
v4->v5:
 - Rebased on top of Tom's RCO work
 - Dropped IFLA_VXLAN_EXTENSION container attribute and embedded IFLA_VXLAN_GBP
   as top level VXLAN attribute like RCO for consistency. 
v3->v4:
 - Patch 1 was no longer needed due to Tom Herbert's 3bf394 ("vxlan: Improve
   support for header flags"). Moved remaining header description to this patch.
 - Zero out vxlan_metadata in vxlan_tnl_send() as suggested by Jesse.
 - Reported enabled extensions to user space as requested by Nicolas.
 - Use VXLAN_HF_GBP instead of bitfield to be in line with Tom's work.
v2->v3:
 - Removed empty struct vxlan_gbp as spotted by Alexei
v1->v2:
 - split GBP header definition into separate struct vxlanhdr_gbp as requested
   by Alexei

 drivers/net/vxlan.c           | 90 ++++++++++++++++++++++++++++++++++++-------
 include/net/vxlan.h           | 81 +++++++++++++++++++++++++++++++++++---
 include/uapi/linux/if_link.h  |  1 +
 net/openvswitch/vport-vxlan.c |  9 +++--
 4 files changed, 160 insertions(+), 21 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 99df0d7..06f7196 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -126,6 +126,7 @@ struct vxlan_dev {
 	__u8		  tos;		/* TOS override */
 	__u8		  ttl;
 	u32		  flags;	/* VXLAN_F_* in vxlan.h */
+	u32		  exts;		/* Enabled extensions */
 
 	struct work_struct sock_work;
 	struct work_struct igmp_join;
@@ -620,7 +621,8 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 			continue;
 
 		vh2 = (struct vxlanhdr *)(p->data + off_vx);
-		if (vh->vx_vni != vh2->vx_vni) {
+		if (vh->vx_flags != vh2->vx_flags ||
+		    vh->vx_vni != vh2->vx_vni) {
 			NAPI_GRO_CB(p)->same_flow = 0;
 			continue;
 		}
@@ -1183,6 +1185,7 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 	struct vxlan_sock *vs;
 	struct vxlanhdr *vxh;
 	u32 flags, vni;
+	struct vxlan_metadata md = {0};
 
 	/* Need Vxlan and inner Ethernet header to be present */
 	if (!pskb_may_pull(skb, VXLAN_HLEN))
@@ -1216,6 +1219,29 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 		vni &= VXLAN_VID_MASK;
 	}
 
+	/* For backwards compatibility, only allow reserved fields to be
+	 * used by VXLAN extensions if explicitly requested.
+	 */
+	if (vs->exts) {
+		if (flags & VXLAN_HF_GBP) {
+			struct vxlanhdr_gbp *gbp;
+
+			if (!(vs->exts & VXLAN_EXT_GBP))
+				goto bad_flags;
+
+			gbp = (struct vxlanhdr_gbp *)vxh;
+			md.gbp = ntohs(gbp->policy_id);
+
+			if (gbp->dont_learn)
+				md.gbp |= VXLAN_GBP_DONT_LEARN;
+
+			if (gbp->policy_applied)
+				md.gbp |= VXLAN_GBP_POLICY_APPLIED;
+
+			flags &= ~VXLAN_GBP_USED_BITS;
+		}
+	}
+
 	if (flags || (vni & ~VXLAN_VID_MASK)) {
 		/* If there are any unprocessed flags remaining treat
 		 * this as a malformed packet. This behavior diverges from
@@ -1229,7 +1255,8 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 		goto bad_flags;
 	}
 
-	vs->rcv(vs, skb, vxh->vx_vni);
+	md.vni = vxh->vx_vni;
+	vs->rcv(vs, skb, &md);
 	return 0;
 
 drop:
@@ -1246,8 +1273,8 @@ error:
 	return 1;
 }
 
-static void vxlan_rcv(struct vxlan_sock *vs,
-		      struct sk_buff *skb, __be32 vx_vni)
+static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb,
+		      struct vxlan_metadata *md)
 {
 	struct iphdr *oip = NULL;
 	struct ipv6hdr *oip6 = NULL;
@@ -1258,7 +1285,7 @@ static void vxlan_rcv(struct vxlan_sock *vs,
 	int err = 0;
 	union vxlan_addr *remote_ip;
 
-	vni = ntohl(vx_vni) >> 8;
+	vni = ntohl(md->vni) >> 8;
 	/* Is this VNI defined? */
 	vxlan = vxlan_vs_find_vni(vs, vni);
 	if (!vxlan)
@@ -1292,6 +1319,7 @@ static void vxlan_rcv(struct vxlan_sock *vs,
 		goto drop;
 
 	skb_reset_network_header(skb);
+	skb->mark = md->gbp;
 
 	if (oip6)
 		err = IP6_ECN_decapsulate(oip6, skb);
@@ -1641,13 +1669,30 @@ static bool route_shortcircuit(struct net_device *dev, struct sk_buff *skb)
 	return false;
 }
 
+static void vxlan_build_gbp_hdr(struct vxlanhdr *vxh, struct vxlan_sock *vs,
+				struct vxlan_metadata *md)
+{
+	struct vxlanhdr_gbp *gbp;
+
+	gbp = (struct vxlanhdr_gbp *)vxh;
+	vxh->vx_flags |= htonl(VXLAN_HF_GBP);
+
+	if (md->gbp & VXLAN_GBP_DONT_LEARN)
+		gbp->dont_learn = 1;
+
+	if (md->gbp & VXLAN_GBP_POLICY_APPLIED)
+		gbp->policy_applied = 1;
+
+	gbp->policy_id = htons(md->gbp & VXLAN_GBP_ID_MASK);
+}
+
 #if IS_ENABLED(CONFIG_IPV6)
 static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 			   struct dst_entry *dst, struct sk_buff *skb,
 			   struct net_device *dev, struct in6_addr *saddr,
 			   struct in6_addr *daddr, __u8 prio, __u8 ttl,
-			   __be16 src_port, __be16 dst_port, __be32 vni,
-			   bool xnet)
+			   __be16 src_port, __be16 dst_port,
+			   struct vxlan_metadata *md, bool xnet)
 {
 	struct vxlanhdr *vxh;
 	int min_headroom;
@@ -1696,7 +1741,7 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 
 	vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
 	vxh->vx_flags = htonl(VXLAN_HF_VNI);
-	vxh->vx_vni = vni;
+	vxh->vx_vni = md->vni;
 
 	if (type & SKB_GSO_TUNNEL_REMCSUM) {
 		u32 data = (skb_checksum_start_offset(skb) - hdrlen) >>
@@ -1714,6 +1759,9 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 		}
 	}
 
+	if (vs->exts & VXLAN_EXT_GBP)
+		vxlan_build_gbp_hdr(vxh, vs, md);
+
 	skb_set_inner_protocol(skb, htons(ETH_P_TEB));
 
 	udp_tunnel6_xmit_skb(vs->sock, dst, skb, dev, saddr, daddr, prio,
@@ -1728,7 +1776,8 @@ err:
 int vxlan_xmit_skb(struct vxlan_sock *vs,
 		   struct rtable *rt, struct sk_buff *skb,
 		   __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
-		   __be16 src_port, __be16 dst_port, __be32 vni, bool xnet)
+		   __be16 src_port, __be16 dst_port,
+		   struct vxlan_metadata *md, bool xnet)
 {
 	struct vxlanhdr *vxh;
 	int min_headroom;
@@ -1771,7 +1820,7 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
 
 	vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
 	vxh->vx_flags = htonl(VXLAN_HF_VNI);
-	vxh->vx_vni = vni;
+	vxh->vx_vni = md->vni;
 
 	if (type & SKB_GSO_TUNNEL_REMCSUM) {
 		u32 data = (skb_checksum_start_offset(skb) - hdrlen) >>
@@ -1789,6 +1838,9 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
 		}
 	}
 
+	if (vs->exts & VXLAN_EXT_GBP)
+		vxlan_build_gbp_hdr(vxh, vs, md);
+
 	skb_set_inner_protocol(skb, htons(ETH_P_TEB));
 
 	return udp_tunnel_xmit_skb(vs->sock, rt, skb, src, dst, tos,
@@ -1849,6 +1901,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 	const struct iphdr *old_iph;
 	struct flowi4 fl4;
 	union vxlan_addr *dst;
+	struct vxlan_metadata md;
 	__be16 src_port = 0, dst_port;
 	u32 vni;
 	__be16 df = 0;
@@ -1919,11 +1972,12 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 
 		tos = ip_tunnel_ecn_encap(tos, old_iph, skb);
 		ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
+		md.vni = htonl(vni << 8);
+		md.gbp = skb->mark;
 
 		err = vxlan_xmit_skb(vxlan->vn_sock, rt, skb,
 				     fl4.saddr, dst->sin.sin_addr.s_addr,
-				     tos, ttl, df, src_port, dst_port,
-				     htonl(vni << 8),
+				     tos, ttl, df, src_port, dst_port, &md,
 				     !net_eq(vxlan->net, dev_net(vxlan->dev)));
 		if (err < 0) {
 			/* skb is already freed. */
@@ -1976,10 +2030,12 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 		}
 
 		ttl = ttl ? : ip6_dst_hoplimit(ndst);
+		md.vni = htonl(vni << 8);
+		md.gbp = skb->mark;
 
 		err = vxlan6_xmit_skb(vxlan->vn_sock, ndst, skb,
 				      dev, &fl6.saddr, &fl6.daddr, 0, ttl,
-				      src_port, dst_port, htonl(vni << 8),
+				      src_port, dst_port, &md,
 				      !net_eq(vxlan->net, dev_net(vxlan->dev)));
 #endif
 	}
@@ -2382,6 +2438,7 @@ static const struct nla_policy vxlan_policy[IFLA_VXLAN_MAX + 1] = {
 	[IFLA_VXLAN_UDP_ZERO_CSUM6_RX]	= { .type = NLA_U8 },
 	[IFLA_VXLAN_REMCSUM_TX]	= { .type = NLA_U8 },
 	[IFLA_VXLAN_REMCSUM_RX]	= { .type = NLA_U8 },
+	[IFLA_VXLAN_GBP]	= { .type = NLA_FLAG, },
 };
 
 static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[])
@@ -2706,6 +2763,9 @@ static int vxlan_newlink(struct net *net, struct net_device *dev,
 	    nla_get_u8(data[IFLA_VXLAN_REMCSUM_RX]))
 		vxlan->flags |= VXLAN_F_REMCSUM_RX;
 
+	if (data[IFLA_VXLAN_GBP])
+		vxlan->exts |= VXLAN_EXT_GBP;
+
 	if (vxlan_find_vni(net, vni, use_ipv6 ? AF_INET6 : AF_INET,
 			   vxlan->dst_port)) {
 		pr_info("duplicate VNI %u\n", vni);
@@ -2851,6 +2911,10 @@ static int vxlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	if (nla_put(skb, IFLA_VXLAN_PORT_RANGE, sizeof(ports), &ports))
 		goto nla_put_failure;
 
+	if (vxlan->exts & VXLAN_EXT_GBP &&
+	    nla_put_flag(skb, IFLA_VXLAN_GBP))
+		goto nla_put_failure;
+
 	return 0;
 
 nla_put_failure:
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index 0a7443b..db02582 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -11,15 +11,76 @@
 #define VNI_HASH_BITS	10
 #define VNI_HASH_SIZE	(1<<VNI_HASH_BITS)
 
-/* VXLAN protocol header */
+/*
+ * VXLAN Group Based Policy Extension:
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |1|-|-|-|1|-|-|-|R|D|R|R|A|R|R|R|        Group Policy ID        |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |                VXLAN Network Identifier (VNI) |   Reserved    |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * D = Don't Learn bit. When set, this bit indicates that the egress
+ *     VTEP MUST NOT learn the source address of the encapsulated frame.
+ *
+ * A = Indicates that the group policy has already been applied to
+ *     this packet. Policies MUST NOT be applied by devices when the
+ *     A bit is set.
+ *
+ * [0] https://tools.ietf.org/html/draft-smith-vxlan-group-policy
+ */
+struct vxlanhdr_gbp {
+	__u8	vx_flags;
+#ifdef __LITTLE_ENDIAN_BITFIELD
+	__u8	reserved_flags1:3,
+		policy_applied:1,
+		reserved_flags2:2,
+		dont_learn:1,
+		reserved_flags3:1;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	__u8	reserved_flags1:1,
+		dont_learn:1,
+		reserved_flags2:2,
+		policy_applied:1,
+		reserved_flags3:3;
+#else
+#error	"Please fix <asm/byteorder.h>"
+#endif
+	__be16	policy_id;
+	__be32	vx_vni;
+};
+
+#define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | 0xFFFFFF)
+
+/* skb->mark mapping
+ *
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+#define VXLAN_GBP_DONT_LEARN		(BIT(6) << 16)
+#define VXLAN_GBP_POLICY_APPLIED	(BIT(3) << 16)
+#define VXLAN_GBP_ID_MASK		(0xFFFF)
+
+/* VXLAN protocol header:
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |G|R|R|R|I|R|R|C|               Reserved                        |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |                VXLAN Network Identifier (VNI) |   Reserved    |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * G = 1	Group Policy (VXLAN-GBP)
+ * I = 1	VXLAN Network Identifier (VNI) present
+ * C = 1	Remote checksum offload (RCO)
+ */
 struct vxlanhdr {
 	__be32 vx_flags;
 	__be32 vx_vni;
 };
 
 /* VXLAN header flags. */
-#define VXLAN_HF_VNI 0x08000000
-#define VXLAN_HF_RCO 0x00200000
+#define VXLAN_HF_RCO BIT(24)
+#define VXLAN_HF_VNI BIT(27)
+#define VXLAN_HF_GBP BIT(31)
 
 /* Remote checksum offload header option */
 #define VXLAN_RCO_MASK  0x7f    /* Last byte of vni field */
@@ -32,14 +93,23 @@ struct vxlanhdr {
 #define VXLAN_VID_MASK  (VXLAN_N_VID - 1)
 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
 
+struct vxlan_metadata {
+	__be32		vni;
+	u32		gbp;
+};
+
 struct vxlan_sock;
-typedef void (vxlan_rcv_t)(struct vxlan_sock *vh, struct sk_buff *skb, __be32 key);
+typedef void (vxlan_rcv_t)(struct vxlan_sock *vh, struct sk_buff *skb,
+			   struct vxlan_metadata *md);
+
+#define VXLAN_EXT_GBP			BIT(0)
 
 /* per UDP socket information */
 struct vxlan_sock {
 	struct hlist_node hlist;
 	vxlan_rcv_t	 *rcv;
 	void		 *data;
+	u32		  exts;
 	struct work_struct del_work;
 	struct socket	 *sock;
 	struct rcu_head	  rcu;
@@ -70,7 +140,8 @@ void vxlan_sock_release(struct vxlan_sock *vs);
 int vxlan_xmit_skb(struct vxlan_sock *vs,
 		   struct rtable *rt, struct sk_buff *skb,
 		   __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
-		   __be16 src_port, __be16 dst_port, __be32 vni, bool xnet);
+		   __be16 src_port, __be16 dst_port, struct vxlan_metadata *md,
+		   bool xnet);
 
 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 						     netdev_features_t features)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index b2723f6..2a8380e 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -372,6 +372,7 @@ enum {
 	IFLA_VXLAN_UDP_ZERO_CSUM6_RX,
 	IFLA_VXLAN_REMCSUM_TX,
 	IFLA_VXLAN_REMCSUM_RX,
+	IFLA_VXLAN_GBP,
 	__IFLA_VXLAN_MAX
 };
 #define IFLA_VXLAN_MAX	(__IFLA_VXLAN_MAX - 1)
diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
index d7c46b3..deed9e3 100644
--- a/net/openvswitch/vport-vxlan.c
+++ b/net/openvswitch/vport-vxlan.c
@@ -59,7 +59,8 @@ static inline struct vxlan_port *vxlan_vport(const struct vport *vport)
 }
 
 /* Called with rcu_read_lock and BH disabled. */
-static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32 vx_vni)
+static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb,
+		      struct vxlan_metadata *md)
 {
 	struct ovs_tunnel_info tun_info;
 	struct vport *vport = vs->data;
@@ -68,7 +69,7 @@ static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32 vx_vni)
 
 	/* Save outer tunnel values */
 	iph = ip_hdr(skb);
-	key = cpu_to_be64(ntohl(vx_vni) >> 8);
+	key = cpu_to_be64(ntohl(md->vni) >> 8);
 	ovs_flow_tun_info_init(&tun_info, iph,
 			       udp_hdr(skb)->source, udp_hdr(skb)->dest,
 			       key, TUNNEL_KEY, NULL, 0);
@@ -146,6 +147,7 @@ static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 	struct vxlan_port *vxlan_port = vxlan_vport(vport);
 	__be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
 	struct ovs_key_ipv4_tunnel *tun_key;
+	struct vxlan_metadata md = {0};
 	struct rtable *rt;
 	struct flowi4 fl;
 	__be16 src_port;
@@ -178,12 +180,13 @@ static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 	skb->ignore_df = 1;
 
 	src_port = udp_flow_src_port(net, skb, 0, 0, true);
+	md.vni = htonl(be64_to_cpu(tun_key->tun_id) << 8);
 
 	err = vxlan_xmit_skb(vxlan_port->vs, rt, skb,
 			     fl.saddr, tun_key->ipv4_dst,
 			     tun_key->ipv4_tos, tun_key->ipv4_ttl, df,
 			     src_port, dst_port,
-			     htonl(be64_to_cpu(tun_key->tun_id) << 8),
+			     &md,
 			     false);
 	if (err < 0)
 		ip_rt_put(rt);
-- 
1.9.3

[PATCH 2/5] vxlan: Only bind to sockets with correct extensions enabled

[Thomas Graf]

A VXLAN net_device looking for an appropriate socket may only consider
a socket which has a matching set of extensions enabled. If the
extensions don't match, return a conflict to have the caller create a
distinct socket with distinct port.

The OVS VXLAN port is kept unaware of extensions at this point.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
v4->v5:
 - No change
v3->v4:
 - No change
v2->v3:
 - No change
v1->v2:
 - Improved commit message, reported by Jesse

 drivers/net/vxlan.c           | 35 +++++++++++++++++++++--------------
 include/net/vxlan.h           |  2 +-
 net/openvswitch/vport-vxlan.c |  2 +-
 3 files changed, 23 insertions(+), 16 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 06f7196..ca94f2f 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -265,14 +265,15 @@ static inline struct vxlan_rdst *first_remote_rtnl(struct vxlan_fdb *fdb)
 }
 
 /* Find VXLAN socket based on network namespace, address family and UDP port */
-static struct vxlan_sock *vxlan_find_sock(struct net *net,
-					  sa_family_t family, __be16 port)
+static struct vxlan_sock *vxlan_find_sock(struct net *net, sa_family_t family,
+					  __be16 port, u32 exts)
 {
 	struct vxlan_sock *vs;
 
 	hlist_for_each_entry_rcu(vs, vs_head(net, port), hlist) {
 		if (inet_sk(vs->sock->sk)->inet_sport == port &&
-		    inet_sk(vs->sock->sk)->sk.sk_family == family)
+		    inet_sk(vs->sock->sk)->sk.sk_family == family &&
+		    vs->exts == exts)
 			return vs;
 	}
 	return NULL;
@@ -292,11 +293,12 @@ static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, u32 id)
 
 /* Look up VNI in a per net namespace table */
 static struct vxlan_dev *vxlan_find_vni(struct net *net, u32 id,
-					sa_family_t family, __be16 port)
+					sa_family_t family, __be16 port,
+					u32 exts)
 {
 	struct vxlan_sock *vs;
 
-	vs = vxlan_find_sock(net, family, port);
+	vs = vxlan_find_sock(net, family, port, exts);
 	if (!vs)
 		return NULL;
 
@@ -1963,7 +1965,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 
 			ip_rt_put(rt);
 			dst_vxlan = vxlan_find_vni(vxlan->net, vni,
-						   dst->sa.sa_family, dst_port);
+						   dst->sa.sa_family, dst_port,
+						   vxlan->exts);
 			if (!dst_vxlan)
 				goto tx_error;
 			vxlan_encap_bypass(skb, vxlan, dst_vxlan);
@@ -2022,7 +2025,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 
 			dst_release(ndst);
 			dst_vxlan = vxlan_find_vni(vxlan->net, vni,
-						   dst->sa.sa_family, dst_port);
+						   dst->sa.sa_family, dst_port,
+						   vxlan->exts);
 			if (!dst_vxlan)
 				goto tx_error;
 			vxlan_encap_bypass(skb, vxlan, dst_vxlan);
@@ -2192,7 +2196,7 @@ static int vxlan_init(struct net_device *dev)
 
 	spin_lock(&vn->sock_lock);
 	vs = vxlan_find_sock(vxlan->net, ipv6 ? AF_INET6 : AF_INET,
-			     vxlan->dst_port);
+			     vxlan->dst_port, vxlan->exts);
 	if (vs && atomic_add_unless(&vs->refcnt, 1, 0)) {
 		/* If we have a socket with same port already, reuse it */
 		vxlan_vs_add_dev(vs, vxlan);
@@ -2532,7 +2536,7 @@ static struct socket *vxlan_create_sock(struct net *net, bool ipv6,
 /* Create new listen socket if needed */
 static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
 					      vxlan_rcv_t *rcv, void *data,
-					      u32 flags)
+					      u32 flags, u32 exts)
 {
 	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
 	struct vxlan_sock *vs;
@@ -2561,6 +2565,7 @@ static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
 	vs->rcv = rcv;
 	vs->data = data;
 	vs->flags = flags;
+	vs->exts = exts;
 
 	/* Initialize the vxlan udp offloads structure */
 	vs->udp_offloads.port = port;
@@ -2585,13 +2590,14 @@ static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
 
 struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 				  vxlan_rcv_t *rcv, void *data,
-				  bool no_share, u32 flags)
+				  bool no_share, u32 flags,
+				  u32 exts)
 {
 	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
 	struct vxlan_sock *vs;
 	bool ipv6 = flags & VXLAN_F_IPV6;
 
-	vs = vxlan_socket_create(net, port, rcv, data, flags);
+	vs = vxlan_socket_create(net, port, rcv, data, flags, exts);
 	if (!IS_ERR(vs))
 		return vs;
 
@@ -2599,7 +2605,7 @@ struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 		return vs;
 
 	spin_lock(&vn->sock_lock);
-	vs = vxlan_find_sock(net, ipv6 ? AF_INET6 : AF_INET, port);
+	vs = vxlan_find_sock(net, ipv6 ? AF_INET6 : AF_INET, port, exts);
 	if (vs && ((vs->rcv != rcv) ||
 		   !atomic_add_unless(&vs->refcnt, 1, 0)))
 			vs = ERR_PTR(-EBUSY);
@@ -2621,7 +2627,8 @@ static void vxlan_sock_work(struct work_struct *work)
 	__be16 port = vxlan->dst_port;
 	struct vxlan_sock *nvs;
 
-	nvs = vxlan_sock_add(net, port, vxlan_rcv, NULL, false, vxlan->flags);
+	nvs = vxlan_sock_add(net, port, vxlan_rcv, NULL, false, vxlan->flags,
+			     vxlan->exts);
 	spin_lock(&vn->sock_lock);
 	if (!IS_ERR(nvs))
 		vxlan_vs_add_dev(nvs, vxlan);
@@ -2767,7 +2774,7 @@ static int vxlan_newlink(struct net *net, struct net_device *dev,
 		vxlan->exts |= VXLAN_EXT_GBP;
 
 	if (vxlan_find_vni(net, vni, use_ipv6 ? AF_INET6 : AF_INET,
-			   vxlan->dst_port)) {
+			   vxlan->dst_port, vxlan->exts)) {
 		pr_info("duplicate VNI %u\n", vni);
 		return -EEXIST;
 	}
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index db02582..446b018 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -133,7 +133,7 @@ struct vxlan_sock {
 
 struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 				  vxlan_rcv_t *rcv, void *data,
-				  bool no_share, u32 flags);
+				  bool no_share, u32 flags, u32 exts);
 
 void vxlan_sock_release(struct vxlan_sock *vs);
 
diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
index deed9e3..40a16fb 100644
--- a/net/openvswitch/vport-vxlan.c
+++ b/net/openvswitch/vport-vxlan.c
@@ -128,7 +128,7 @@ static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
 	vxlan_port = vxlan_vport(vport);
 	strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
 
-	vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, 0);
+	vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, 0, 0);
 	if (IS_ERR(vs)) {
 		ovs_vport_free(vport);
 		return (void *)vs;
-- 
1.9.3

[PATCH 3/5] openvswitch: Rename GENEVE_TUN_OPTS() to TUN_METADATA_OPTS()

[Thomas Graf]

Also factors out Geneve validation code into a new separate function
validate_and_copy_geneve_opts().

A subsequent patch will introduce VXLAN options. Rename the existing
GENEVE_TUN_OPTS() to reflect its extended purpose of carrying generic
tunnel metadata options.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
v4->v5:
 - No change
v3->v4:
 - Renamed validate_and_copy_geneve_opts() to validate_geneve_opts() as
   suggested by Jesse
v2->v3:
 - No change
v1->v2:
 - Don't rename genev_tun_opt_from_nlattr() and keep it Geneve specific,
   pointed out by Jesse.
 - Factor out Geneve specific validation code into separate function as
   requested by Jesse.

 net/openvswitch/flow.c         |  2 +-
 net/openvswitch/flow.h         | 14 ++++----
 net/openvswitch/flow_netlink.c | 72 +++++++++++++++++++++++-------------------
 3 files changed, 47 insertions(+), 41 deletions(-)

diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
index df334fe..e2c348b 100644
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -691,7 +691,7 @@ int ovs_flow_key_extract(const struct ovs_tunnel_info *tun_info,
 			BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
 						   8)) - 1
 					> sizeof(key->tun_opts));
-			memcpy(GENEVE_OPTS(key, tun_info->options_len),
+			memcpy(TUN_METADATA_OPTS(key, tun_info->options_len),
 			       tun_info->options, tun_info->options_len);
 			key->tun_opts_len = tun_info->options_len;
 		} else {
diff --git a/net/openvswitch/flow.h b/net/openvswitch/flow.h
index a8b30f3..d3d0a40 100644
--- a/net/openvswitch/flow.h
+++ b/net/openvswitch/flow.h
@@ -53,7 +53,7 @@ struct ovs_key_ipv4_tunnel {
 
 struct ovs_tunnel_info {
 	struct ovs_key_ipv4_tunnel tunnel;
-	const struct geneve_opt *options;
+	const void *options;
 	u8 options_len;
 };
 
@@ -61,10 +61,10 @@ struct ovs_tunnel_info {
  * maximum size. This allows us to get the benefits of variable length
  * matching for small options.
  */
-#define GENEVE_OPTS(flow_key, opt_len)	\
-	((struct geneve_opt *)((flow_key)->tun_opts + \
-			       FIELD_SIZEOF(struct sw_flow_key, tun_opts) - \
-			       opt_len))
+#define TUN_METADATA_OFFSET(opt_len) \
+	(FIELD_SIZEOF(struct sw_flow_key, tun_opts) - opt_len)
+#define TUN_METADATA_OPTS(flow_key, opt_len) \
+	((void *)((flow_key)->tun_opts + TUN_METADATA_OFFSET(opt_len)))
 
 static inline void __ovs_flow_tun_info_init(struct ovs_tunnel_info *tun_info,
 					    __be32 saddr, __be32 daddr,
@@ -73,7 +73,7 @@ static inline void __ovs_flow_tun_info_init(struct ovs_tunnel_info *tun_info,
 					    __be16 tp_dst,
 					    __be64 tun_id,
 					    __be16 tun_flags,
-					    const struct geneve_opt *opts,
+					    const void *opts,
 					    u8 opts_len)
 {
 	tun_info->tunnel.tun_id = tun_id;
@@ -105,7 +105,7 @@ static inline void ovs_flow_tun_info_init(struct ovs_tunnel_info *tun_info,
 					  __be16 tp_dst,
 					  __be64 tun_id,
 					  __be16 tun_flags,
-					  const struct geneve_opt *opts,
+					  const void *opts,
 					  u8 opts_len)
 {
 	__ovs_flow_tun_info_init(tun_info, iph->saddr, iph->daddr,
diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c
index d1eecf7..2e8a9cd 100644
--- a/net/openvswitch/flow_netlink.c
+++ b/net/openvswitch/flow_netlink.c
@@ -432,8 +432,7 @@ static int genev_tun_opt_from_nlattr(const struct nlattr *a,
 		SW_FLOW_KEY_PUT(match, tun_opts_len, 0xff, true);
 	}
 
-	opt_key_offset = (unsigned long)GENEVE_OPTS((struct sw_flow_key *)0,
-						    nla_len(a));
+	opt_key_offset = TUN_METADATA_OFFSET(nla_len(a));
 	SW_FLOW_KEY_MEMCPY_OFFSET(match, opt_key_offset, nla_data(a),
 				  nla_len(a), is_mask);
 	return 0;
@@ -558,8 +557,7 @@ static int ipv4_tun_from_nlattr(const struct nlattr *attr,
 
 static int __ipv4_tun_to_nlattr(struct sk_buff *skb,
 				const struct ovs_key_ipv4_tunnel *output,
-				const struct geneve_opt *tun_opts,
-				int swkey_tun_opts_len)
+				const void *tun_opts, int swkey_tun_opts_len)
 {
 	if (output->tun_flags & TUNNEL_KEY &&
 	    nla_put_be64(skb, OVS_TUNNEL_KEY_ATTR_ID, output->tun_id))
@@ -600,8 +598,7 @@ static int __ipv4_tun_to_nlattr(struct sk_buff *skb,
 
 static int ipv4_tun_to_nlattr(struct sk_buff *skb,
 			      const struct ovs_key_ipv4_tunnel *output,
-			      const struct geneve_opt *tun_opts,
-			      int swkey_tun_opts_len)
+			      const void *tun_opts, int swkey_tun_opts_len)
 {
 	struct nlattr *nla;
 	int err;
@@ -1148,10 +1145,10 @@ int ovs_nla_put_flow(const struct sw_flow_key *swkey,
 		goto nla_put_failure;
 
 	if ((swkey->tun_key.ipv4_dst || is_mask)) {
-		const struct geneve_opt *opts = NULL;
+		const void *opts = NULL;
 
 		if (output->tun_key.tun_flags & TUNNEL_OPTIONS_PRESENT)
-			opts = GENEVE_OPTS(output, swkey->tun_opts_len);
+			opts = TUN_METADATA_OPTS(output, swkey->tun_opts_len);
 
 		if (ipv4_tun_to_nlattr(skb, &output->tun_key, opts,
 				       swkey->tun_opts_len))
@@ -1540,6 +1537,34 @@ void ovs_match_init(struct sw_flow_match *match,
 	}
 }
 
+static int validate_geneve_opts(struct sw_flow_key *key)
+{
+	struct geneve_opt *option;
+	int opts_len = key->tun_opts_len;
+	bool crit_opt = false;
+
+	option = (struct geneve_opt *)TUN_METADATA_OPTS(key, key->tun_opts_len);
+	while (opts_len > 0) {
+		int len;
+
+		if (opts_len < sizeof(*option))
+			return -EINVAL;
+
+		len = sizeof(*option) + option->length * 4;
+		if (len > opts_len)
+			return -EINVAL;
+
+		crit_opt |= !!(option->type & GENEVE_CRIT_OPT_TYPE);
+
+		option = (struct geneve_opt *)((u8 *)option + len);
+		opts_len -= len;
+	};
+
+	key->tun_key.tun_flags |= crit_opt ? TUNNEL_CRIT_OPT : 0;
+
+	return 0;
+}
+
 static int validate_and_copy_set_tun(const struct nlattr *attr,
 				     struct sw_flow_actions **sfa, bool log)
 {
@@ -1555,28 +1580,9 @@ static int validate_and_copy_set_tun(const struct nlattr *attr,
 		return err;
 
 	if (key.tun_opts_len) {
-		struct geneve_opt *option = GENEVE_OPTS(&key,
-							key.tun_opts_len);
-		int opts_len = key.tun_opts_len;
-		bool crit_opt = false;
-
-		while (opts_len > 0) {
-			int len;
-
-			if (opts_len < sizeof(*option))
-				return -EINVAL;
-
-			len = sizeof(*option) + option->length * 4;
-			if (len > opts_len)
-				return -EINVAL;
-
-			crit_opt |= !!(option->type & GENEVE_CRIT_OPT_TYPE);
-
-			option = (struct geneve_opt *)((u8 *)option + len);
-			opts_len -= len;
-		};
-
-		key.tun_key.tun_flags |= crit_opt ? TUNNEL_CRIT_OPT : 0;
+		err = validate_geneve_opts(&key);
+		if (err < 0)
+			return err;
 	};
 
 	start = add_nested_action_start(sfa, OVS_ACTION_ATTR_SET, log);
@@ -1597,9 +1603,9 @@ static int validate_and_copy_set_tun(const struct nlattr *attr,
 		 * everything else will go away after flow setup. We can append
 		 * it to tun_info and then point there.
 		 */
-		memcpy((tun_info + 1), GENEVE_OPTS(&key, key.tun_opts_len),
-		       key.tun_opts_len);
-		tun_info->options = (struct geneve_opt *)(tun_info + 1);
+		memcpy((tun_info + 1),
+		       TUN_METADATA_OPTS(&key, key.tun_opts_len), key.tun_opts_len);
+		tun_info->options = (tun_info + 1);
 	} else {
 		tun_info->options = NULL;
 	}
-- 
1.9.3

[PATCH 4/5] openvswitch: Allow for any level of nesting in flow attributes

[Thomas Graf]

nlattr_set() is currently hardcoded to two levels of nesting. This change
introduces struct ovs_len_tbl to define minimal length requirements plus
next level nesting tables to traverse the key attributes to arbitrary depth.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
v4->v5:
 - No change
v3->v4:
 - No change. The spotted bug is unrelatd to this series and will be fixed
   in a separate patch
v2->v3:
 - No change
v1->v2:
 - New patch to allow nested Netlink attributes inside
   OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS

 net/openvswitch/flow_netlink.c | 106 ++++++++++++++++++++++-------------------
 1 file changed, 56 insertions(+), 50 deletions(-)

diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c
index 2e8a9cd..518941c 100644
--- a/net/openvswitch/flow_netlink.c
+++ b/net/openvswitch/flow_netlink.c
@@ -50,6 +50,13 @@
 
 #include "flow_netlink.h"
 
+struct ovs_len_tbl {
+	int len;
+	const struct ovs_len_tbl *next;
+};
+
+#define OVS_ATTR_NESTED -1
+
 static void update_range(struct sw_flow_match *match,
 			 size_t offset, size_t size, bool is_mask)
 {
@@ -289,29 +296,44 @@ size_t ovs_key_attr_size(void)
 		+ nla_total_size(28); /* OVS_KEY_ATTR_ND */
 }
 
+static const struct ovs_len_tbl ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1] = {
+	[OVS_TUNNEL_KEY_ATTR_ID]	    = { .len = sizeof(u64) },
+	[OVS_TUNNEL_KEY_ATTR_IPV4_SRC]	    = { .len = sizeof(u32) },
+	[OVS_TUNNEL_KEY_ATTR_IPV4_DST]	    = { .len = sizeof(u32) },
+	[OVS_TUNNEL_KEY_ATTR_TOS]	    = { .len = 1 },
+	[OVS_TUNNEL_KEY_ATTR_TTL]	    = { .len = 1 },
+	[OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT] = { .len = 0 },
+	[OVS_TUNNEL_KEY_ATTR_CSUM]	    = { .len = 0 },
+	[OVS_TUNNEL_KEY_ATTR_TP_SRC]	    = { .len = sizeof(u16) },
+	[OVS_TUNNEL_KEY_ATTR_TP_DST]	    = { .len = sizeof(u16) },
+	[OVS_TUNNEL_KEY_ATTR_OAM]	    = { .len = 0 },
+	[OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS]   = { .len = OVS_ATTR_NESTED },
+};
+
 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
-static const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
-	[OVS_KEY_ATTR_ENCAP] = -1,
-	[OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
-	[OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
-	[OVS_KEY_ATTR_SKB_MARK] = sizeof(u32),
-	[OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
-	[OVS_KEY_ATTR_VLAN] = sizeof(__be16),
-	[OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
-	[OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
-	[OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
-	[OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
-	[OVS_KEY_ATTR_TCP_FLAGS] = sizeof(__be16),
-	[OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
-	[OVS_KEY_ATTR_SCTP] = sizeof(struct ovs_key_sctp),
-	[OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
-	[OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
-	[OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
-	[OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
-	[OVS_KEY_ATTR_RECIRC_ID] = sizeof(u32),
-	[OVS_KEY_ATTR_DP_HASH] = sizeof(u32),
-	[OVS_KEY_ATTR_TUNNEL] = -1,
-	[OVS_KEY_ATTR_MPLS] = sizeof(struct ovs_key_mpls),
+static const struct ovs_len_tbl ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
+	[OVS_KEY_ATTR_ENCAP]	 = { .len = OVS_ATTR_NESTED },
+	[OVS_KEY_ATTR_PRIORITY]	 = { .len = sizeof(u32) },
+	[OVS_KEY_ATTR_IN_PORT]	 = { .len = sizeof(u32) },
+	[OVS_KEY_ATTR_SKB_MARK]	 = { .len = sizeof(u32) },
+	[OVS_KEY_ATTR_ETHERNET]	 = { .len = sizeof(struct ovs_key_ethernet) },
+	[OVS_KEY_ATTR_VLAN]	 = { .len = sizeof(__be16) },
+	[OVS_KEY_ATTR_ETHERTYPE] = { .len = sizeof(__be16) },
+	[OVS_KEY_ATTR_IPV4]	 = { .len = sizeof(struct ovs_key_ipv4) },
+	[OVS_KEY_ATTR_IPV6]	 = { .len = sizeof(struct ovs_key_ipv6) },
+	[OVS_KEY_ATTR_TCP]	 = { .len = sizeof(struct ovs_key_tcp) },
+	[OVS_KEY_ATTR_TCP_FLAGS] = { .len = sizeof(__be16) },
+	[OVS_KEY_ATTR_UDP]	 = { .len = sizeof(struct ovs_key_udp) },
+	[OVS_KEY_ATTR_SCTP]	 = { .len = sizeof(struct ovs_key_sctp) },
+	[OVS_KEY_ATTR_ICMP]	 = { .len = sizeof(struct ovs_key_icmp) },
+	[OVS_KEY_ATTR_ICMPV6]	 = { .len = sizeof(struct ovs_key_icmpv6) },
+	[OVS_KEY_ATTR_ARP]	 = { .len = sizeof(struct ovs_key_arp) },
+	[OVS_KEY_ATTR_ND]	 = { .len = sizeof(struct ovs_key_nd) },
+	[OVS_KEY_ATTR_RECIRC_ID] = { .len = sizeof(u32) },
+	[OVS_KEY_ATTR_DP_HASH]	 = { .len = sizeof(u32) },
+	[OVS_KEY_ATTR_TUNNEL]	 = { .len = OVS_ATTR_NESTED,
+				     .next = ovs_tunnel_key_lens, },
+	[OVS_KEY_ATTR_MPLS]	 = { .len = sizeof(struct ovs_key_mpls) },
 };
 
 static bool is_all_zero(const u8 *fp, size_t size)
@@ -352,8 +374,8 @@ static int __parse_flow_nlattrs(const struct nlattr *attr,
 			return -EINVAL;
 		}
 
-		expected_len = ovs_key_lens[type];
-		if (nla_len(nla) != expected_len && expected_len != -1) {
+		expected_len = ovs_key_lens[type].len;
+		if (nla_len(nla) != expected_len && expected_len != OVS_ATTR_NESTED) {
 			OVS_NLERR(log, "Key %d has unexpected len %d expected %d",
 				  type, nla_len(nla), expected_len);
 			return -EINVAL;
@@ -451,30 +473,16 @@ static int ipv4_tun_from_nlattr(const struct nlattr *attr,
 		int type = nla_type(a);
 		int err;
 
-		static const u32 ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1] = {
-			[OVS_TUNNEL_KEY_ATTR_ID] = sizeof(u64),
-			[OVS_TUNNEL_KEY_ATTR_IPV4_SRC] = sizeof(u32),
-			[OVS_TUNNEL_KEY_ATTR_IPV4_DST] = sizeof(u32),
-			[OVS_TUNNEL_KEY_ATTR_TOS] = 1,
-			[OVS_TUNNEL_KEY_ATTR_TTL] = 1,
-			[OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT] = 0,
-			[OVS_TUNNEL_KEY_ATTR_CSUM] = 0,
-			[OVS_TUNNEL_KEY_ATTR_TP_SRC] = sizeof(u16),
-			[OVS_TUNNEL_KEY_ATTR_TP_DST] = sizeof(u16),
-			[OVS_TUNNEL_KEY_ATTR_OAM] = 0,
-			[OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS] = -1,
-		};
-
 		if (type > OVS_TUNNEL_KEY_ATTR_MAX) {
 			OVS_NLERR(log, "Tunnel attr %d out of range max %d",
 				  type, OVS_TUNNEL_KEY_ATTR_MAX);
 			return -EINVAL;
 		}
 
-		if (ovs_tunnel_key_lens[type] != nla_len(a) &&
-		    ovs_tunnel_key_lens[type] != -1) {
+		if (ovs_tunnel_key_lens[type].len != nla_len(a) &&
+		    ovs_tunnel_key_lens[type].len != OVS_ATTR_NESTED) {
 			OVS_NLERR(log, "Tunnel attr %d has unexpected len %d expected %d",
-				  type, nla_len(a), ovs_tunnel_key_lens[type]);
+				  type, nla_len(a), ovs_tunnel_key_lens[type].len);
 			return -EINVAL;
 		}
 
@@ -912,18 +920,16 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs,
 	return 0;
 }
 
-static void nlattr_set(struct nlattr *attr, u8 val, bool is_attr_mask_key)
+static void nlattr_set(struct nlattr *attr, u8 val,
+		       const struct ovs_len_tbl *tbl)
 {
 	struct nlattr *nla;
 	int rem;
 
 	/* The nlattr stream should already have been validated */
 	nla_for_each_nested(nla, attr, rem) {
-		/* We assume that ovs_key_lens[type] == -1 means that type is a
-		 * nested attribute
-		 */
-		if (is_attr_mask_key && ovs_key_lens[nla_type(nla)] == -1)
-			nlattr_set(nla, val, false);
+		if (tbl && tbl[nla_type(nla)].len == OVS_ATTR_NESTED)
+			nlattr_set(nla, val, tbl[nla_type(nla)].next);
 		else
 			memset(nla_data(nla), val, nla_len(nla));
 	}
@@ -931,7 +937,7 @@ static void nlattr_set(struct nlattr *attr, u8 val, bool is_attr_mask_key)
 
 static void mask_set_nlattr(struct nlattr *attr, u8 val)
 {
-	nlattr_set(attr, val, true);
+	nlattr_set(attr, val, ovs_key_lens);
 }
 
 /**
@@ -1628,8 +1634,8 @@ static int validate_set(const struct nlattr *a,
 		return -EINVAL;
 
 	if (key_type > OVS_KEY_ATTR_MAX ||
-	    (ovs_key_lens[key_type] != nla_len(ovs_key) &&
-	     ovs_key_lens[key_type] != -1))
+	    (ovs_key_lens[key_type].len != nla_len(ovs_key) &&
+	     ovs_key_lens[key_type].len != OVS_ATTR_NESTED))
 		return -EINVAL;
 
 	switch (key_type) {
-- 
1.9.3

[PATCH 5/5] openvswitch: Support VXLAN Group Policy extension

[Thomas Graf]

Introduces support for the group policy extension to the VXLAN virtual
port. The extension is disabled by default and only enabled if the user
has provided the respective configuration.

  ovs-vsctl add-port br0 vxlan0 -- \
     set Interface vxlan0 type=vxlan options:exts=gbp

The configuration interface to enable the extension is based on a new
attribute OVS_VXLAN_EXT_GBP nested inside OVS_TUNNEL_ATTR_EXTENSION
which can carry additional extensions as needed in the future.

The group policy metadata is stored as binary blob (struct ovs_vxlan_opts)
internally just like Geneve options but transported as nested Netlink
attributes to user space.

Renames the existing TUNNEL_OPTIONS_PRESENT to TUNNEL_GENEVE_OPT with the
binary value kept intact, a new flag TUNNEL_VXLAN_OPT is introduced.

The attributes OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS and existing
OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS are implemented mutually exclusive.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
---
v4->v5:
 - No change
v3->v4:
 - Fixed OVS_VXLAN_EXT_MAX->OVS_VXLAN_EXT_GBP typo as spotted by Jesse
 - Only applied tunnel options if they are of the right type as
   suggested by Jesse
v2->v3:
 - No change
v1->v2:
 - Addressed Jesse's request to transport VXLAN options as Netlink
   attributes instead of a binary blob. Allows a partial transport of
   VXLAN extensions. Internally, the datapath continues to use a binary
   blob (defined in vport-vxlan.h) for performance reasons.
 - Added new TUNNEL_GENEVE_OPT and TUNNEL_VXLAN_OPT flags to mark
   tunnel option flavour
 - Correctly report VXLAN options to user space

 include/net/ip_tunnels.h         |   5 +-
 include/uapi/linux/openvswitch.h |  11 ++++
 net/openvswitch/flow_netlink.c   | 114 ++++++++++++++++++++++++++++++++++-----
 net/openvswitch/vport-geneve.c   |  15 ++++--
 net/openvswitch/vport-vxlan.c    |  82 +++++++++++++++++++++++++++-
 net/openvswitch/vport-vxlan.h    |  11 ++++
 6 files changed, 218 insertions(+), 20 deletions(-)
 create mode 100644 net/openvswitch/vport-vxlan.h

diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 25a59eb..ce4db3c 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -97,7 +97,10 @@ struct ip_tunnel {
 #define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
 #define TUNNEL_OAM		__cpu_to_be16(0x0200)
 #define TUNNEL_CRIT_OPT		__cpu_to_be16(0x0400)
-#define TUNNEL_OPTIONS_PRESENT	__cpu_to_be16(0x0800)
+#define TUNNEL_GENEVE_OPT	__cpu_to_be16(0x0800)
+#define TUNNEL_VXLAN_OPT	__cpu_to_be16(0x1000)
+
+#define TUNNEL_OPTIONS_PRESENT	(TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT)
 
 struct tnl_ptk_info {
 	__be16 flags;
diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index 3a6dcaa..e474c95 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -248,11 +248,21 @@ enum ovs_vport_attr {
 
 #define OVS_VPORT_ATTR_MAX (__OVS_VPORT_ATTR_MAX - 1)
 
+enum {
+	OVS_VXLAN_EXT_UNSPEC,
+	OVS_VXLAN_EXT_GBP,	/* Flag or __u32 */
+	__OVS_VXLAN_EXT_MAX,
+};
+
+#define OVS_VXLAN_EXT_MAX (__OVS_VXLAN_EXT_MAX - 1)
+
+
 /* OVS_VPORT_ATTR_OPTIONS attributes for tunnels.
  */
 enum {
 	OVS_TUNNEL_ATTR_UNSPEC,
 	OVS_TUNNEL_ATTR_DST_PORT, /* 16-bit UDP port, used by L4 tunnels. */
+	OVS_TUNNEL_ATTR_EXTENSION,
 	__OVS_TUNNEL_ATTR_MAX
 };
 
@@ -324,6 +334,7 @@ enum ovs_tunnel_key_attr {
 	OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS,        /* Array of Geneve options. */
 	OVS_TUNNEL_KEY_ATTR_TP_SRC,		/* be16 src Transport Port. */
 	OVS_TUNNEL_KEY_ATTR_TP_DST,		/* be16 dst Transport Port. */
+	OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS,		/* Nested OVS_VXLAN_EXT_* */
 	__OVS_TUNNEL_KEY_ATTR_MAX
 };
 
diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c
index 518941c..d210d1b 100644
--- a/net/openvswitch/flow_netlink.c
+++ b/net/openvswitch/flow_netlink.c
@@ -49,6 +49,7 @@
 #include <net/mpls.h>
 
 #include "flow_netlink.h"
+#include "vport-vxlan.h"
 
 struct ovs_len_tbl {
 	int len;
@@ -268,6 +269,9 @@ size_t ovs_tun_key_attr_size(void)
 		+ nla_total_size(0)    /* OVS_TUNNEL_KEY_ATTR_CSUM */
 		+ nla_total_size(0)    /* OVS_TUNNEL_KEY_ATTR_OAM */
 		+ nla_total_size(256)  /* OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS */
+		/* OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS is mutually exclusive with
+		 * OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS and covered by it.
+		 */
 		+ nla_total_size(2)    /* OVS_TUNNEL_KEY_ATTR_TP_SRC */
 		+ nla_total_size(2);   /* OVS_TUNNEL_KEY_ATTR_TP_DST */
 }
@@ -308,6 +312,7 @@ static const struct ovs_len_tbl ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1]
 	[OVS_TUNNEL_KEY_ATTR_TP_DST]	    = { .len = sizeof(u16) },
 	[OVS_TUNNEL_KEY_ATTR_OAM]	    = { .len = 0 },
 	[OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS]   = { .len = OVS_ATTR_NESTED },
+	[OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS]    = { .len = OVS_ATTR_NESTED },
 };
 
 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
@@ -460,6 +465,41 @@ static int genev_tun_opt_from_nlattr(const struct nlattr *a,
 	return 0;
 }
 
+static const struct nla_policy vxlan_opt_policy[OVS_VXLAN_EXT_MAX + 1] = {
+	[OVS_VXLAN_EXT_GBP]	= { .type = NLA_U32 },
+};
+
+static int vxlan_tun_opt_from_nlattr(const struct nlattr *a,
+				     struct sw_flow_match *match, bool is_mask,
+				     bool log)
+{
+	struct nlattr *tb[OVS_VXLAN_EXT_MAX+1];
+	unsigned long opt_key_offset;
+	struct ovs_vxlan_opts opts;
+	int err;
+
+	BUILD_BUG_ON(sizeof(opts) > sizeof(match->key->tun_opts));
+
+	err = nla_parse_nested(tb, OVS_VXLAN_EXT_MAX, a, vxlan_opt_policy);
+	if (err < 0)
+		return err;
+
+	memset(&opts, 0, sizeof(opts));
+
+	if (tb[OVS_VXLAN_EXT_GBP])
+		opts.gbp = nla_get_u32(tb[OVS_VXLAN_EXT_GBP]);
+
+	if (!is_mask)
+		SW_FLOW_KEY_PUT(match, tun_opts_len, sizeof(opts), false);
+	else
+		SW_FLOW_KEY_PUT(match, tun_opts_len, 0xff, true);
+
+	opt_key_offset = TUN_METADATA_OFFSET(sizeof(opts));
+	SW_FLOW_KEY_MEMCPY_OFFSET(match, opt_key_offset, &opts, sizeof(opts),
+				  is_mask);
+	return 0;
+}
+
 static int ipv4_tun_from_nlattr(const struct nlattr *attr,
 				struct sw_flow_match *match, bool is_mask,
 				bool log)
@@ -468,6 +508,7 @@ static int ipv4_tun_from_nlattr(const struct nlattr *attr,
 	int rem;
 	bool ttl = false;
 	__be16 tun_flags = 0;
+	int opts_type = 0;
 
 	nla_for_each_nested(a, attr, rem) {
 		int type = nla_type(a);
@@ -527,11 +568,30 @@ static int ipv4_tun_from_nlattr(const struct nlattr *attr,
 			tun_flags |= TUNNEL_OAM;
 			break;
 		case OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS:
+			if (opts_type) {
+				OVS_NLERR(log, "Multiple metadata blocks provided");
+				return -EINVAL;
+			}
+
 			err = genev_tun_opt_from_nlattr(a, match, is_mask, log);
 			if (err)
 				return err;
 
-			tun_flags |= TUNNEL_OPTIONS_PRESENT;
+			tun_flags |= TUNNEL_GENEVE_OPT;
+			opts_type = type;
+			break;
+		case OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS:
+			if (opts_type) {
+				OVS_NLERR(log, "Multiple metadata blocks provided");
+				return -EINVAL;
+			}
+
+			err = vxlan_tun_opt_from_nlattr(a, match, is_mask, log);
+			if (err)
+				return err;
+
+			tun_flags |= TUNNEL_VXLAN_OPT;
+			opts_type = type;
 			break;
 		default:
 			OVS_NLERR(log, "Unknown IPv4 tunnel attribute %d",
@@ -560,6 +620,23 @@ static int ipv4_tun_from_nlattr(const struct nlattr *attr,
 		}
 	}
 
+	return opts_type;
+}
+
+static int vxlan_opt_to_nlattr(struct sk_buff *skb,
+			       const void *tun_opts, int swkey_tun_opts_len)
+{
+	const struct ovs_vxlan_opts *opts = tun_opts;
+	struct nlattr *nla;
+
+	nla = nla_nest_start(skb, OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS);
+	if (!nla)
+		return -EMSGSIZE;
+
+	if (nla_put_u32(skb, OVS_VXLAN_EXT_GBP, opts->gbp) < 0)
+		return -EMSGSIZE;
+
+	nla_nest_end(skb, nla);
 	return 0;
 }
 
@@ -596,10 +673,15 @@ static int __ipv4_tun_to_nlattr(struct sk_buff *skb,
 	if ((output->tun_flags & TUNNEL_OAM) &&
 	    nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_OAM))
 		return -EMSGSIZE;
-	if (tun_opts &&
-	    nla_put(skb, OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS,
-		    swkey_tun_opts_len, tun_opts))
-		return -EMSGSIZE;
+	if (tun_opts) {
+		if (output->tun_flags & TUNNEL_GENEVE_OPT &&
+		    nla_put(skb, OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS,
+			    swkey_tun_opts_len, tun_opts))
+			return -EMSGSIZE;
+		else if (output->tun_flags & TUNNEL_VXLAN_OPT &&
+			 vxlan_opt_to_nlattr(skb, tun_opts, swkey_tun_opts_len))
+			return -EMSGSIZE;
+	}
 
 	return 0;
 }
@@ -680,7 +762,7 @@ static int metadata_from_nlattrs(struct sw_flow_match *match,  u64 *attrs,
 	}
 	if (*attrs & (1 << OVS_KEY_ATTR_TUNNEL)) {
 		if (ipv4_tun_from_nlattr(a[OVS_KEY_ATTR_TUNNEL], match,
-					 is_mask, log))
+					 is_mask, log) < 0)
 			return -EINVAL;
 		*attrs &= ~(1 << OVS_KEY_ATTR_TUNNEL);
 	}
@@ -1578,17 +1660,23 @@ static int validate_and_copy_set_tun(const struct nlattr *attr,
 	struct sw_flow_key key;
 	struct ovs_tunnel_info *tun_info;
 	struct nlattr *a;
-	int err, start;
+	int err, start, opts_type;
 
 	ovs_match_init(&match, &key, NULL);
-	err = ipv4_tun_from_nlattr(nla_data(attr), &match, false, log);
-	if (err)
-		return err;
+	opts_type = ipv4_tun_from_nlattr(nla_data(attr), &match, false, log);
+	if (opts_type < 0)
+		return opts_type;
 
 	if (key.tun_opts_len) {
-		err = validate_geneve_opts(&key);
-		if (err < 0)
-			return err;
+		switch (opts_type) {
+		case OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS:
+			err = validate_geneve_opts(&key);
+			if (err < 0)
+				return err;
+			break;
+		case OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS:
+			break;
+		}
 	};
 
 	start = add_nested_action_start(sfa, OVS_ACTION_ATTR_SET, log);
diff --git a/net/openvswitch/vport-geneve.c b/net/openvswitch/vport-geneve.c
index 2daf144..17b0840 100644
--- a/net/openvswitch/vport-geneve.c
+++ b/net/openvswitch/vport-geneve.c
@@ -88,7 +88,7 @@ static void geneve_rcv(struct geneve_sock *gs, struct sk_buff *skb)
 
 	opts_len = geneveh->opt_len * 4;
 
-	flags = TUNNEL_KEY | TUNNEL_OPTIONS_PRESENT |
+	flags = TUNNEL_KEY | TUNNEL_GENEVE_OPT |
 		(udp_hdr(skb)->check != 0 ? TUNNEL_CSUM : 0) |
 		(geneveh->oam ? TUNNEL_OAM : 0) |
 		(geneveh->critical ? TUNNEL_CRIT_OPT : 0);
@@ -178,7 +178,7 @@ static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 	__be16 sport;
 	struct rtable *rt;
 	struct flowi4 fl;
-	u8 vni[3];
+	u8 vni[3], opts_len, *opts;
 	__be16 df;
 	int err;
 
@@ -209,11 +209,18 @@ static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 	tunnel_id_to_vni(tun_key->tun_id, vni);
 	skb->ignore_df = 1;
 
+	if (tun_key->tun_flags & TUNNEL_GENEVE_OPT) {
+		opts = (u8 *)tun_info->options;
+		opts_len = tun_info->options_len;
+	} else {
+		opts = NULL;
+		opts_len = 0;
+	}
+
 	err = geneve_xmit_skb(geneve_port->gs, rt, skb, fl.saddr,
 			      tun_key->ipv4_dst, tun_key->ipv4_tos,
 			      tun_key->ipv4_ttl, df, sport, dport,
-			      tun_key->tun_flags, vni,
-			      tun_info->options_len, (u8 *)tun_info->options,
+			      tun_key->tun_flags, vni, opts_len, opts,
 			      false);
 	if (err < 0)
 		ip_rt_put(rt);
diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
index 40a16fb..9f47c23 100644
--- a/net/openvswitch/vport-vxlan.c
+++ b/net/openvswitch/vport-vxlan.c
@@ -40,6 +40,7 @@
 
 #include "datapath.h"
 #include "vport.h"
+#include "vport-vxlan.h"
 
 /**
  * struct vxlan_port - Keeps track of open UDP ports
@@ -49,6 +50,7 @@
 struct vxlan_port {
 	struct vxlan_sock *vs;
 	char name[IFNAMSIZ];
+	u32 exts; /* VXLAN_EXT_* in <net/vxlan.h> */
 };
 
 static struct vport_ops ovs_vxlan_vport_ops;
@@ -63,16 +65,26 @@ static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb,
 		      struct vxlan_metadata *md)
 {
 	struct ovs_tunnel_info tun_info;
+	struct vxlan_port *vxlan_port;
 	struct vport *vport = vs->data;
 	struct iphdr *iph;
+	struct ovs_vxlan_opts opts = {
+		.gbp = md->gbp,
+	};
 	__be64 key;
+	__be16 flags;
+
+	flags = TUNNEL_KEY;
+	vxlan_port = vxlan_vport(vport);
+	if (vxlan_port->exts & VXLAN_EXT_GBP)
+		flags |= TUNNEL_VXLAN_OPT;
 
 	/* Save outer tunnel values */
 	iph = ip_hdr(skb);
 	key = cpu_to_be64(ntohl(md->vni) >> 8);
 	ovs_flow_tun_info_init(&tun_info, iph,
 			       udp_hdr(skb)->source, udp_hdr(skb)->dest,
-			       key, TUNNEL_KEY, NULL, 0);
+			       key, flags, &opts, sizeof(opts));
 
 	ovs_vport_receive(vport, skb, &tun_info);
 }
@@ -84,6 +96,21 @@ static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
 
 	if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
 		return -EMSGSIZE;
+
+	if (vxlan_port->exts) {
+		struct nlattr *exts;
+
+		exts = nla_nest_start(skb, OVS_TUNNEL_ATTR_EXTENSION);
+		if (!exts)
+			return -EMSGSIZE;
+
+		if (vxlan_port->exts & VXLAN_EXT_GBP &&
+		    nla_put_flag(skb, OVS_VXLAN_EXT_GBP))
+			return -EMSGSIZE;
+
+		nla_nest_end(skb, exts);
+	}
+
 	return 0;
 }
 
@@ -96,6 +123,31 @@ static void vxlan_tnl_destroy(struct vport *vport)
 	ovs_vport_deferred_free(vport);
 }
 
+static const struct nla_policy exts_policy[OVS_VXLAN_EXT_MAX+1] = {
+	[OVS_VXLAN_EXT_GBP]	= { .type = NLA_FLAG, },
+};
+
+static int vxlan_configure_exts(struct vport *vport, struct nlattr *attr)
+{
+	struct nlattr *exts[OVS_VXLAN_EXT_MAX+1];
+	struct vxlan_port *vxlan_port;
+	int err;
+
+	if (nla_len(attr) < sizeof(struct nlattr))
+		return -EINVAL;
+
+	err = nla_parse_nested(exts, OVS_VXLAN_EXT_MAX, attr, exts_policy);
+	if (err < 0)
+		return err;
+
+	vxlan_port = vxlan_vport(vport);
+
+	if (exts[OVS_VXLAN_EXT_GBP])
+		vxlan_port->exts |= VXLAN_EXT_GBP;
+
+	return 0;
+}
+
 static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
 {
 	struct net *net = ovs_dp_get_net(parms->dp);
@@ -128,7 +180,17 @@ static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
 	vxlan_port = vxlan_vport(vport);
 	strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
 
-	vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, 0, 0);
+	a = nla_find_nested(options, OVS_TUNNEL_ATTR_EXTENSION);
+	if (a) {
+		err = vxlan_configure_exts(vport, a);
+		if (err) {
+			ovs_vport_free(vport);
+			goto error;
+		}
+	}
+
+	vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true, 0,
+			    vxlan_port->exts);
 	if (IS_ERR(vs)) {
 		ovs_vport_free(vport);
 		return (void *)vs;
@@ -141,6 +203,21 @@ error:
 	return ERR_PTR(err);
 }
 
+static int vxlan_ext_gbp(struct sk_buff *skb)
+{
+	const struct ovs_tunnel_info *tun_info;
+	const struct ovs_vxlan_opts *opts;
+
+	tun_info = OVS_CB(skb)->egress_tun_info;
+	opts = tun_info->options;
+
+	if (tun_info->tunnel.tun_flags & TUNNEL_VXLAN_OPT &&
+	    tun_info->options_len >= sizeof(*opts))
+		return opts->gbp;
+	else
+		return 0;
+}
+
 static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 {
 	struct net *net = ovs_dp_get_net(vport->dp);
@@ -181,6 +258,7 @@ static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 
 	src_port = udp_flow_src_port(net, skb, 0, 0, true);
 	md.vni = htonl(be64_to_cpu(tun_key->tun_id) << 8);
+	md.gbp = vxlan_ext_gbp(skb);
 
 	err = vxlan_xmit_skb(vxlan_port->vs, rt, skb,
 			     fl.saddr, tun_key->ipv4_dst,
diff --git a/net/openvswitch/vport-vxlan.h b/net/openvswitch/vport-vxlan.h
new file mode 100644
index 0000000..4b08233e
--- /dev/null
+++ b/net/openvswitch/vport-vxlan.h
@@ -0,0 +1,11 @@
+#ifndef VPORT_VXLAN_H
+#define VPORT_VXLAN_H 1
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+struct ovs_vxlan_opts {
+	__u32 gbp;
+};
+
+#endif
-- 
1.9.3

Re: [PATCH 1/5] vxlan: Group Policy extension

[Tom Herbert]

> diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
> index 99df0d7..06f7196 100644
> --- a/drivers/net/vxlan.c
> +++ b/drivers/net/vxlan.c
> @@ -126,6 +126,7 @@ struct vxlan_dev {
>         __u8              tos;          /* TOS override */
>         __u8              ttl;
>         u32               flags;        /* VXLAN_F_* in vxlan.h */
> +       u32               exts;         /* Enabled extensions */
>

Thomas, why not just make a VXAM_F_GPB flag? Then this setting can be
saved in the flags for vxlan_dev and vxlan_sock so no exts field.

Tom


>         struct work_struct sock_work;
>         struct work_struct igmp_join;
> @@ -620,7 +621,8 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
>                         continue;
>

Re: [PATCH 1/5] vxlan: Group Policy extension

[Thomas Graf]

On 01/14/15 at 04:18pm, Tom Herbert wrote:
> > diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
> > index 99df0d7..06f7196 100644
> > --- a/drivers/net/vxlan.c
> > +++ b/drivers/net/vxlan.c
> > @@ -126,6 +126,7 @@ struct vxlan_dev {
> >         __u8              tos;          /* TOS override */
> >         __u8              ttl;
> >         u32               flags;        /* VXLAN_F_* in vxlan.h */
> > +       u32               exts;         /* Enabled extensions */
> >
> 
> Thomas, why not just make a VXAM_F_GPB flag? Then this setting can be
> saved in the flags for vxlan_dev and vxlan_sock so no exts field.

Because we need to compare enabled extensions in vxlan_find_sock() to
make sure we are not sharing a VXLAN socket with extensions enabled
with a user which does not have the same extensions enabled.

However, we do not want vxlan_find_sock() to compare all flags.

So we need a bitmap that is ignored during the share check (flags) and
a bitmap that must match to allow sharing (exts).

The RCO extension is currently suffering from this bug which is causing
a compatibility issue. I explained in the thread of your patch. I was
under the imrpession that you would either send a v2 or fix it in a
follow-up.

Re: [PATCH 1/5] vxlan: Group Policy extension

[Tom Herbert]

On Wed, Jan 14, 2015 at 4:23 PM, Thomas Graf <tgraf@suug.ch> wrote:
> On 01/14/15 at 04:18pm, Tom Herbert wrote:
>> > diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
>> > index 99df0d7..06f7196 100644
>> > --- a/drivers/net/vxlan.c
>> > +++ b/drivers/net/vxlan.c
>> > @@ -126,6 +126,7 @@ struct vxlan_dev {
>> >         __u8              tos;          /* TOS override */
>> >         __u8              ttl;
>> >         u32               flags;        /* VXLAN_F_* in vxlan.h */
>> > +       u32               exts;         /* Enabled extensions */
>> >
>>
>> Thomas, why not just make a VXAM_F_GPB flag? Then this setting can be
>> saved in the flags for vxlan_dev and vxlan_sock so no exts field.
>
> Because we need to compare enabled extensions in vxlan_find_sock() to
> make sure we are not sharing a VXLAN socket with extensions enabled
> with a user which does not have the same extensions enabled.
>
> However, we do not want vxlan_find_sock() to compare all flags.
>
> So we need a bitmap that is ignored during the share check (flags) and
> a bitmap that must match to allow sharing (exts).
>
> The RCO extension is currently suffering from this bug which is causing
> a compatibility issue. I explained in the thread of your patch. I was
> under the imrpession that you would either send a v2 or fix it in a
> follow-up.

As I mentioned, we would also need to match receive checksum settings
which is not appropriately called an extension. A mask of interesting
flags could be used to do the comparison in vxlan_find_sock.

Re: [PATCH 1/5] vxlan: Group Policy extension

[Thomas Graf]

On 01/14/15 at 05:08pm, Tom Herbert wrote:
> On Wed, Jan 14, 2015 at 4:23 PM, Thomas Graf <tgraf@suug.ch> wrote:
> > Because we need to compare enabled extensions in vxlan_find_sock() to
> > make sure we are not sharing a VXLAN socket with extensions enabled
> > with a user which does not have the same extensions enabled.
> >
> > However, we do not want vxlan_find_sock() to compare all flags.
> >
> > So we need a bitmap that is ignored during the share check (flags) and
> > a bitmap that must match to allow sharing (exts).
> >
> > The RCO extension is currently suffering from this bug which is causing
> > a compatibility issue. I explained in the thread of your patch. I was
> > under the imrpession that you would either send a v2 or fix it in a
> > follow-up.
> 
> As I mentioned, we would also need to match receive checksum settings
> which is not appropriately called an extension. A mask of interesting
> flags could be used to do the comparison in vxlan_find_sock.

What exactly is the problem of having a distinct bitmap used by
extensions? It is the least error prone method because it's clear that
all extensions must match and we don't have to maintain an additional
bitmask which can be forgotten to be updated.

If you need to compare additional receive checksum settings for RCO
then that should be separate because as you say it's not an extension.

Re: [PATCH 1/5] vxlan: Group Policy extension

[Thomas Graf]

On 01/15/15 at 01:28am, Thomas Graf wrote:
> What exactly is the problem of having a distinct bitmap used by
> extensions? It is the least error prone method because it's clear that
> all extensions must match and we don't have to maintain an additional
> bitmask which can be forgotten to be updated.
> 
> If you need to compare additional receive checksum settings for RCO
> then that should be separate because as you say it's not an extension.

Tom,

OK. I have changed it to use flags instead of exts in v6. You should
be able to add whatever RCO flags need to be matched in
vxlan_find_sock() to the VXLAN_F_UNSHAREABLE bitmask.

Hope this makes everybody happy ;-)

Re: [PATCH 1/5] vxlan: Group Policy extension

[Tom Herbert]

On Wed, Jan 14, 2015 at 6:55 PM, Thomas Graf <tgraf@suug.ch> wrote:
> On 01/15/15 at 01:28am, Thomas Graf wrote:
>> What exactly is the problem of having a distinct bitmap used by
>> extensions? It is the least error prone method because it's clear that
>> all extensions must match and we don't have to maintain an additional
>> bitmask which can be forgotten to be updated.
>>
>> If you need to compare additional receive checksum settings for RCO
>> then that should be separate because as you say it's not an extension.
>
> Tom,
>
> OK. I have changed it to use flags instead of exts in v6. You should
> be able to add whatever RCO flags need to be matched in
> vxlan_find_sock() to the VXLAN_F_UNSHAREABLE bitmask.
>
> Hope this makes everybody happy ;-)

Awesome. Thanks!