include/net/vxlan.h - kernel/quantenna - Git at Google

 #ifndef __NET_VXLAN_H
 #define __NET_VXLAN_H 1

 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/if_vlan.h>
 #include <linux/skbuff.h>
 #include <linux/netdevice.h>
 #include <linux/udp.h>
 #include <net/dst_metadata.h>

 /* VXLAN protocol (RFC 7348) header:
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |R|R|R|R|I|R|R|R|               Reserved                        |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *
  * I = VXLAN Network Identifier (VNI) present.
  */
 struct vxlanhdr {
 	__be32 vx_flags;
 	__be32 vx_vni;
 };

 /* VXLAN header flags. */
 #define VXLAN_HF_VNI	cpu_to_be32(BIT(27))

 #define VXLAN_N_VID     (1u << 24)
 #define VXLAN_VID_MASK  (VXLAN_N_VID - 1)
 #define VXLAN_VNI_MASK	cpu_to_be32(VXLAN_VID_MASK << 8)
 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))

 #define VNI_HASH_BITS	10
 #define VNI_HASH_SIZE	(1<<VNI_HASH_BITS)
 #define FDB_HASH_BITS	8
 #define FDB_HASH_SIZE	(1<<FDB_HASH_BITS)

 /* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X):
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |R|R|R|R|I|R|R|R|R|R|C|              Reserved                   |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |           VXLAN Network Identifier (VNI)      |O| Csum start  |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *
  * C = Remote checksum offload bit. When set indicates that the
  *     remote checksum offload data is present.
  *
  * O = Offset bit. Indicates the checksum offset relative to
  *     checksum start.
  *
  * Csum start = Checksum start divided by two.
  *
  * http://tools.ietf.org/html/draft-herbert-vxlan-rco
  */

 /* VXLAN-RCO header flags. */
 #define VXLAN_HF_RCO	cpu_to_be32(BIT(21))

 /* Remote checksum offload header option */
 #define VXLAN_RCO_MASK	cpu_to_be32(0x7f)  /* Last byte of vni field */
 #define VXLAN_RCO_UDP	cpu_to_be32(0x80)  /* Indicate UDP RCO (TCP when not set *) */
 #define VXLAN_RCO_SHIFT	1		   /* Left shift of start */
 #define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
 #define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT)

 /*
  * VXLAN Group Based Policy Extension (VXLAN_F_GBP):
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *
  * G = Group Policy ID present.
  *
  * 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.
  *
  * 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;
 };

 /* VXLAN-GBP header flags. */
 #define VXLAN_HF_GBP	cpu_to_be32(BIT(31))

 #define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(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 Generic Protocol Extension (VXLAN_F_GPE):
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |R|R|Ver|I|P|R|O|       Reserved                |Next Protocol  |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *
  * Ver = Version. Indicates VXLAN GPE protocol version.
  *
  * P = Next Protocol Bit. The P bit is set to indicate that the
  *     Next Protocol field is present.
  *
  * O = OAM Flag Bit. The O bit is set to indicate that the packet
  *     is an OAM packet.
  *
  * Next Protocol = This 8 bit field indicates the protocol header
  * immediately following the VXLAN GPE header.
  *
  * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01
  */

 struct vxlanhdr_gpe {
 #if defined(__LITTLE_ENDIAN_BITFIELD)
 	u8	oam_flag:1,
 		reserved_flags1:1,
 		np_applied:1,
 		instance_applied:1,
 		version:2,
 reserved_flags2:2;
 #elif defined(__BIG_ENDIAN_BITFIELD)
 	u8	reserved_flags2:2,
 		version:2,
 		instance_applied:1,
 		np_applied:1,
 		reserved_flags1:1,
 		oam_flag:1;
 #endif
 	u8	reserved_flags3;
 	u8	reserved_flags4;
 	u8	next_protocol;
 	__be32	vx_vni;
 };

 /* VXLAN-GPE header flags. */
 #define VXLAN_HF_VER	cpu_to_be32(BIT(29) | BIT(28))
 #define VXLAN_HF_NP	cpu_to_be32(BIT(26))
 #define VXLAN_HF_OAM	cpu_to_be32(BIT(24))

 #define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \
 			     cpu_to_be32(0xff))

 /* VXLAN-GPE header Next Protocol. */
 #define VXLAN_GPE_NP_IPV4      0x01
 #define VXLAN_GPE_NP_IPV6      0x02
 #define VXLAN_GPE_NP_ETHERNET  0x03
 #define VXLAN_GPE_NP_NSH       0x04

 struct vxlan_metadata {
 	u32		gbp;
 };

 /* per UDP socket information */
 struct vxlan_sock {
 	struct hlist_node hlist;
 	struct socket	 *sock;
 	struct hlist_head vni_list[VNI_HASH_SIZE];
 	atomic_t	  refcnt;
 	u32		  flags;
 };

 union vxlan_addr {
 	struct sockaddr_in sin;
 	struct sockaddr_in6 sin6;
 	struct sockaddr sa;
 };

 struct vxlan_rdst {
 	union vxlan_addr	 remote_ip;
 	__be16			 remote_port;
 	__be32			 remote_vni;
 	u32			 remote_ifindex;
 	struct list_head	 list;
 	struct rcu_head		 rcu;
 	struct dst_cache	 dst_cache;
 };

 struct vxlan_config {
 	union vxlan_addr	remote_ip;
 	union vxlan_addr	saddr;
 	__be32			vni;
 	int			remote_ifindex;
 	int			mtu;
 	__be16			dst_port;
 	u16			port_min;
 	u16			port_max;
 	u8			tos;
 	u8			ttl;
 	__be32			label;
 	u32			flags;
 	unsigned long		age_interval;
 	unsigned int		addrmax;
 	bool			no_share;
 };

 /* Pseudo network device */
 struct vxlan_dev {
 	struct hlist_node hlist;	/* vni hash table */
 	struct list_head  next;		/* vxlan's per namespace list */
 	struct vxlan_sock *vn4_sock;	/* listening socket for IPv4 */
 #if IS_ENABLED(CONFIG_IPV6)
 	struct vxlan_sock *vn6_sock;	/* listening socket for IPv6 */
 #endif
 	struct net_device *dev;
 	struct net	  *net;		/* netns for packet i/o */
 	struct vxlan_rdst default_dst;	/* default destination */
 	u32		  flags;	/* VXLAN_F_* in vxlan.h */

 	struct timer_list age_timer;
 	spinlock_t	  hash_lock;
 	unsigned int	  addrcnt;
 	struct gro_cells  gro_cells;

 	struct vxlan_config	cfg;

 	struct hlist_head fdb_head[FDB_HASH_SIZE];
 };

 #define VXLAN_F_LEARN			0x01
 #define VXLAN_F_PROXY			0x02
 #define VXLAN_F_RSC			0x04
 #define VXLAN_F_L2MISS			0x08
 #define VXLAN_F_L3MISS			0x10
 #define VXLAN_F_IPV6			0x20
 #define VXLAN_F_UDP_ZERO_CSUM_TX	0x40
 #define VXLAN_F_UDP_ZERO_CSUM6_TX	0x80
 #define VXLAN_F_UDP_ZERO_CSUM6_RX	0x100
 #define VXLAN_F_REMCSUM_TX		0x200
 #define VXLAN_F_REMCSUM_RX		0x400
 #define VXLAN_F_GBP			0x800
 #define VXLAN_F_REMCSUM_NOPARTIAL	0x1000
 #define VXLAN_F_COLLECT_METADATA	0x2000
 #define VXLAN_F_GPE			0x4000

 /* Flags that are used in the receive path. These flags must match in
  * order for a socket to be shareable
  */
 #define VXLAN_F_RCV_FLAGS		(VXLAN_F_GBP |			\
 					 VXLAN_F_GPE |			\
 					 VXLAN_F_UDP_ZERO_CSUM6_RX |	\
 					 VXLAN_F_REMCSUM_RX |		\
 					 VXLAN_F_REMCSUM_NOPARTIAL |	\
 					 VXLAN_F_COLLECT_METADATA)

 /* Flags that can be set together with VXLAN_F_GPE. */
 #define VXLAN_F_ALLOWED_GPE		(VXLAN_F_GPE |			\
 					 VXLAN_F_IPV6 |			\
 					 VXLAN_F_UDP_ZERO_CSUM_TX |	\
 					 VXLAN_F_UDP_ZERO_CSUM6_TX |	\
 					 VXLAN_F_UDP_ZERO_CSUM6_RX |	\
 					 VXLAN_F_COLLECT_METADATA)

 struct net_device *vxlan_dev_create(struct net *net, const char *name,
 				    u8 name_assign_type, struct vxlan_config *conf);

 static inline __be16 vxlan_dev_dst_port(struct vxlan_dev *vxlan,
 					unsigned short family)
 {
 #if IS_ENABLED(CONFIG_IPV6)
 	if (family == AF_INET6)
 		return inet_sk(vxlan->vn6_sock->sock->sk)->inet_sport;
 #endif
 	return inet_sk(vxlan->vn4_sock->sock->sk)->inet_sport;
 }

 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 						     netdev_features_t features)
 {
 	u8 l4_hdr = 0;

 	if (!skb->encapsulation)
 		return features;

 	switch (vlan_get_protocol(skb)) {
 	case htons(ETH_P_IP):
 		l4_hdr = ip_hdr(skb)->protocol;
 		break;
 	case htons(ETH_P_IPV6):
 		l4_hdr = ipv6_hdr(skb)->nexthdr;
 		break;
 	default:
 		return features;;
 	}

 	if ((l4_hdr == IPPROTO_UDP) &&
 	    (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
 	     skb->inner_protocol != htons(ETH_P_TEB) ||
 	     (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
 	      sizeof(struct udphdr) + sizeof(struct vxlanhdr)) ||
 	     (skb->ip_summed != CHECKSUM_NONE &&
 	      !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
 		return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);

 	return features;
 }

 /* IP header + UDP + VXLAN + Ethernet header */
 #define VXLAN_HEADROOM (20 + 8 + 8 + 14)
 /* IPv6 header + UDP + VXLAN + Ethernet header */
 #define VXLAN6_HEADROOM (40 + 8 + 8 + 14)

 static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb)
 {
 	return (struct vxlanhdr *)(udp_hdr(skb) + 1);
 }

 static inline __be32 vxlan_vni(__be32 vni_field)
 {
 #if defined(__BIG_ENDIAN)
 	return (__force __be32)((__force u32)vni_field >> 8);
 #else
 	return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
 #endif
 }

 static inline __be32 vxlan_vni_field(__be32 vni)
 {
 #if defined(__BIG_ENDIAN)
 	return (__force __be32)((__force u32)vni << 8);
 #else
 	return (__force __be32)((__force u32)vni >> 8);
 #endif
 }

 static inline __be32 vxlan_tun_id_to_vni(__be64 tun_id)
 {
 #if defined(__BIG_ENDIAN)
 	return (__force __be32)tun_id;
 #else
 	return (__force __be32)((__force u64)tun_id >> 32);
 #endif
 }

 static inline __be64 vxlan_vni_to_tun_id(__be32 vni)
 {
 #if defined(__BIG_ENDIAN)
 	return (__force __be64)vni;
 #else
 	return (__force __be64)((u64)(__force u32)vni << 32);
 #endif
 }

 static inline size_t vxlan_rco_start(__be32 vni_field)
 {
 	return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
 }

 static inline size_t vxlan_rco_offset(__be32 vni_field)
 {
 	return (vni_field & VXLAN_RCO_UDP) ?
 		offsetof(struct udphdr, check) :
 		offsetof(struct tcphdr, check);
 }

 static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
 {
 	__be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);

 	if (offset == offsetof(struct udphdr, check))
 		vni_field |= VXLAN_RCO_UDP;
 	return vni_field;
 }

 static inline void vxlan_get_rx_port(struct net_device *netdev)
 {
 	ASSERT_RTNL();
 	call_netdevice_notifiers(NETDEV_OFFLOAD_PUSH_VXLAN, netdev);
 }

 static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
 {
 	return vs->sock->sk->sk_family;
 }

 #endif
	#ifndef __NET_VXLAN_H
	#define __NET_VXLAN_H 1

	#include <linux/ip.h>
	#include <linux/ipv6.h>
	#include <linux/if_vlan.h>
	#include <linux/skbuff.h>
	#include <linux/netdevice.h>
	#include <linux/udp.h>
	#include <net/dst_metadata.h>

	/* VXLAN protocol (RFC 7348) header:
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \|R\|R\|R\|R\|I\|R\|R\|R\| Reserved \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \| VXLAN Network Identifier (VNI) \| Reserved \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	*
	* I = VXLAN Network Identifier (VNI) present.
	*/
	struct vxlanhdr {
	__be32 vx_flags;
	__be32 vx_vni;
	};

	/* VXLAN header flags. */
	#define VXLAN_HF_VNI cpu_to_be32(BIT(27))

	#define VXLAN_N_VID (1u << 24)
	#define VXLAN_VID_MASK (VXLAN_N_VID - 1)
	#define VXLAN_VNI_MASK cpu_to_be32(VXLAN_VID_MASK << 8)
	#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))

	#define VNI_HASH_BITS 10
	#define VNI_HASH_SIZE (1<<VNI_HASH_BITS)
	#define FDB_HASH_BITS 8
	#define FDB_HASH_SIZE (1<<FDB_HASH_BITS)

	/* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X):
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \|R\|R\|R\|R\|I\|R\|R\|R\|R\|R\|C\| Reserved \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \| VXLAN Network Identifier (VNI) \|O\| Csum start \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	*
	* C = Remote checksum offload bit. When set indicates that the
	* remote checksum offload data is present.
	*
	* O = Offset bit. Indicates the checksum offset relative to
	* checksum start.
	*
	* Csum start = Checksum start divided by two.
	*
	* http://tools.ietf.org/html/draft-herbert-vxlan-rco
	*/

	/* VXLAN-RCO header flags. */
	#define VXLAN_HF_RCO cpu_to_be32(BIT(21))

	/* Remote checksum offload header option */
	#define VXLAN_RCO_MASK cpu_to_be32(0x7f) /* Last byte of vni field */
	#define VXLAN_RCO_UDP cpu_to_be32(0x80) /* Indicate UDP RCO (TCP when not set ) /
	#define VXLAN_RCO_SHIFT 1 /* Left shift of start */
	#define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
	#define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT)

	/*
	* VXLAN Group Based Policy Extension (VXLAN_F_GBP):
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \|G\|R\|R\|R\|I\|R\|R\|R\|R\|D\|R\|R\|A\|R\|R\|R\| Group Policy ID \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \| VXLAN Network Identifier (VNI) \| Reserved \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	*
	* G = Group Policy ID present.
	*
	* 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.
	*
	* 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;
	};

	/* VXLAN-GBP header flags. */
	#define VXLAN_HF_GBP cpu_to_be32(BIT(31))

	#define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP \| cpu_to_be32(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 Generic Protocol Extension (VXLAN_F_GPE):
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \|R\|R\|Ver\|I\|P\|R\|O\| Reserved \|Next Protocol \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \| VXLAN Network Identifier (VNI) \| Reserved \|
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	*
	* Ver = Version. Indicates VXLAN GPE protocol version.
	*
	* P = Next Protocol Bit. The P bit is set to indicate that the
	* Next Protocol field is present.
	*
	* O = OAM Flag Bit. The O bit is set to indicate that the packet
	* is an OAM packet.
	*
	* Next Protocol = This 8 bit field indicates the protocol header
	* immediately following the VXLAN GPE header.
	*
	* https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01
	*/

	struct vxlanhdr_gpe {
	#if defined(__LITTLE_ENDIAN_BITFIELD)
	u8 oam_flag:1,
	reserved_flags1:1,
	np_applied:1,
	instance_applied:1,
	version:2,
	reserved_flags2:2;
	#elif defined(__BIG_ENDIAN_BITFIELD)
	u8 reserved_flags2:2,
	version:2,
	instance_applied:1,
	np_applied:1,
	reserved_flags1:1,
	oam_flag:1;
	#endif
	u8 reserved_flags3;
	u8 reserved_flags4;
	u8 next_protocol;
	__be32 vx_vni;
	};

	/* VXLAN-GPE header flags. */
	#define VXLAN_HF_VER cpu_to_be32(BIT(29) \| BIT(28))
	#define VXLAN_HF_NP cpu_to_be32(BIT(26))
	#define VXLAN_HF_OAM cpu_to_be32(BIT(24))

	#define VXLAN_GPE_USED_BITS (VXLAN_HF_VER \| VXLAN_HF_NP \| VXLAN_HF_OAM \| \
	cpu_to_be32(0xff))

	/* VXLAN-GPE header Next Protocol. */
	#define VXLAN_GPE_NP_IPV4 0x01
	#define VXLAN_GPE_NP_IPV6 0x02
	#define VXLAN_GPE_NP_ETHERNET 0x03
	#define VXLAN_GPE_NP_NSH 0x04

	struct vxlan_metadata {
	u32 gbp;
	};

	/* per UDP socket information */
	struct vxlan_sock {
	struct hlist_node hlist;
	struct socket *sock;
	struct hlist_head vni_list[VNI_HASH_SIZE];
	atomic_t refcnt;
	u32 flags;
	};

	union vxlan_addr {
	struct sockaddr_in sin;
	struct sockaddr_in6 sin6;
	struct sockaddr sa;
	};

	struct vxlan_rdst {
	union vxlan_addr remote_ip;
	__be16 remote_port;
	__be32 remote_vni;
	u32 remote_ifindex;
	struct list_head list;
	struct rcu_head rcu;
	struct dst_cache dst_cache;
	};

	struct vxlan_config {
	union vxlan_addr remote_ip;
	union vxlan_addr saddr;
	__be32 vni;
	int remote_ifindex;
	int mtu;
	__be16 dst_port;
	u16 port_min;
	u16 port_max;
	u8 tos;
	u8 ttl;
	__be32 label;
	u32 flags;
	unsigned long age_interval;
	unsigned int addrmax;
	bool no_share;
	};

	/* Pseudo network device */
	struct vxlan_dev {
	struct hlist_node hlist; /* vni hash table */
	struct list_head next; /* vxlan's per namespace list */
	struct vxlan_sock vn4_sock; / listening socket for IPv4 */
	#if IS_ENABLED(CONFIG_IPV6)
	struct vxlan_sock vn6_sock; / listening socket for IPv6 */
	#endif
	struct net_device *dev;
	struct net net; / netns for packet i/o */
	struct vxlan_rdst default_dst; /* default destination */
	u32 flags; /* VXLAN_F_* in vxlan.h */

	struct timer_list age_timer;
	spinlock_t hash_lock;
	unsigned int addrcnt;
	struct gro_cells gro_cells;

	struct vxlan_config cfg;

	struct hlist_head fdb_head[FDB_HASH_SIZE];
	};

	#define VXLAN_F_LEARN 0x01
	#define VXLAN_F_PROXY 0x02
	#define VXLAN_F_RSC 0x04
	#define VXLAN_F_L2MISS 0x08
	#define VXLAN_F_L3MISS 0x10
	#define VXLAN_F_IPV6 0x20
	#define VXLAN_F_UDP_ZERO_CSUM_TX 0x40
	#define VXLAN_F_UDP_ZERO_CSUM6_TX 0x80
	#define VXLAN_F_UDP_ZERO_CSUM6_RX 0x100
	#define VXLAN_F_REMCSUM_TX 0x200
	#define VXLAN_F_REMCSUM_RX 0x400
	#define VXLAN_F_GBP 0x800
	#define VXLAN_F_REMCSUM_NOPARTIAL 0x1000
	#define VXLAN_F_COLLECT_METADATA 0x2000
	#define VXLAN_F_GPE 0x4000

	/* Flags that are used in the receive path. These flags must match in
	* order for a socket to be shareable
	*/
	#define VXLAN_F_RCV_FLAGS (VXLAN_F_GBP \| \
	VXLAN_F_GPE \| \
	VXLAN_F_UDP_ZERO_CSUM6_RX \| \
	VXLAN_F_REMCSUM_RX \| \
	VXLAN_F_REMCSUM_NOPARTIAL \| \
	VXLAN_F_COLLECT_METADATA)

	/* Flags that can be set together with VXLAN_F_GPE. */
	#define VXLAN_F_ALLOWED_GPE (VXLAN_F_GPE \| \
	VXLAN_F_IPV6 \| \
	VXLAN_F_UDP_ZERO_CSUM_TX \| \
	VXLAN_F_UDP_ZERO_CSUM6_TX \| \
	VXLAN_F_UDP_ZERO_CSUM6_RX \| \
	VXLAN_F_COLLECT_METADATA)

	struct net_device vxlan_dev_create(struct net net, const char *name,
	u8 name_assign_type, struct vxlan_config *conf);

	static inline __be16 vxlan_dev_dst_port(struct vxlan_dev *vxlan,
	unsigned short family)
	{
	#if IS_ENABLED(CONFIG_IPV6)
	if (family == AF_INET6)
	return inet_sk(vxlan->vn6_sock->sock->sk)->inet_sport;
	#endif
	return inet_sk(vxlan->vn4_sock->sock->sk)->inet_sport;
	}

	static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
	netdev_features_t features)
	{
	u8 l4_hdr = 0;

	if (!skb->encapsulation)
	return features;

	switch (vlan_get_protocol(skb)) {
	case htons(ETH_P_IP):
	l4_hdr = ip_hdr(skb)->protocol;
	break;
	case htons(ETH_P_IPV6):
	l4_hdr = ipv6_hdr(skb)->nexthdr;
	break;
	default:
	return features;;
	}

	if ((l4_hdr == IPPROTO_UDP) &&
	(skb->inner_protocol_type != ENCAP_TYPE_ETHER \|\|
	skb->inner_protocol != htons(ETH_P_TEB) \|\|
	(skb_inner_mac_header(skb) - skb_transport_header(skb) !=
	sizeof(struct udphdr) + sizeof(struct vxlanhdr)) \|\|
	(skb->ip_summed != CHECKSUM_NONE &&
	!can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
	return features & ~(NETIF_F_CSUM_MASK \| NETIF_F_GSO_MASK);

	return features;
	}

	/* IP header + UDP + VXLAN + Ethernet header */
	#define VXLAN_HEADROOM (20 + 8 + 8 + 14)
	/* IPv6 header + UDP + VXLAN + Ethernet header */
	#define VXLAN6_HEADROOM (40 + 8 + 8 + 14)

	static inline struct vxlanhdr vxlan_hdr(struct sk_buff skb)
	{
	return (struct vxlanhdr *)(udp_hdr(skb) + 1);
	}

	static inline __be32 vxlan_vni(__be32 vni_field)
	{
	#if defined(__BIG_ENDIAN)
	return (__force __be32)((__force u32)vni_field >> 8);
	#else
	return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
	#endif
	}

	static inline __be32 vxlan_vni_field(__be32 vni)
	{
	#if defined(__BIG_ENDIAN)
	return (__force __be32)((__force u32)vni << 8);
	#else
	return (__force __be32)((__force u32)vni >> 8);
	#endif
	}

	static inline __be32 vxlan_tun_id_to_vni(__be64 tun_id)
	{
	#if defined(__BIG_ENDIAN)
	return (__force __be32)tun_id;
	#else
	return (__force __be32)((__force u64)tun_id >> 32);
	#endif
	}

	static inline __be64 vxlan_vni_to_tun_id(__be32 vni)
	{
	#if defined(__BIG_ENDIAN)
	return (__force __be64)vni;
	#else
	return (__force __be64)((u64)(__force u32)vni << 32);
	#endif
	}

	static inline size_t vxlan_rco_start(__be32 vni_field)
	{
	return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
	}

	static inline size_t vxlan_rco_offset(__be32 vni_field)
	{
	return (vni_field & VXLAN_RCO_UDP) ?
	offsetof(struct udphdr, check) :
	offsetof(struct tcphdr, check);
	}

	static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
	{
	__be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);

	if (offset == offsetof(struct udphdr, check))
	vni_field \|= VXLAN_RCO_UDP;
	return vni_field;
	}

	static inline void vxlan_get_rx_port(struct net_device *netdev)
	{
	ASSERT_RTNL();
	call_netdevice_notifiers(NETDEV_OFFLOAD_PUSH_VXLAN, netdev);
	}

	static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
	{
	return vs->sock->sk->sk_family;
	}

	#endif