include/net/ip_tunnels.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __NET_IP_TUNNELS_H
 #define __NET_IP_TUNNELS_H 1

 #include <linux/if_tunnel.h>
 #include <linux/netdevice.h>
 #include <linux/skbuff.h>
 #include <linux/socket.h>
 #include <linux/types.h>
 #include <linux/u64_stats_sync.h>
 #include <linux/bitops.h>

 #include <net/dsfield.h>
 #include <net/gro_cells.h>
 #include <net/inet_ecn.h>
 #include <net/netns/generic.h>
 #include <net/rtnetlink.h>
 #include <net/lwtunnel.h>
 #include <net/dst_cache.h>

 #if IS_ENABLED(CONFIG_IPV6)
 #include <net/ipv6.h>
 #include <net/ip6_fib.h>
 #include <net/ip6_route.h>
 #endif

 /* Keep error state on tunnel for 30 sec */
 #define IPTUNNEL_ERR_TIMEO	(30*HZ)

 /* Used to memset ip_tunnel padding. */
 #define IP_TUNNEL_KEY_SIZE	offsetofend(struct ip_tunnel_key, tp_dst)

 /* Used to memset ipv4 address padding. */
 #define IP_TUNNEL_KEY_IPV4_PAD	offsetofend(struct ip_tunnel_key, u.ipv4.dst)
 #define IP_TUNNEL_KEY_IPV4_PAD_LEN				\
 	(sizeof_field(struct ip_tunnel_key, u) -		\
 	 sizeof_field(struct ip_tunnel_key, u.ipv4))

 struct ip_tunnel_key {
 	__be64			tun_id;
 	union {
 		struct {
 			__be32	src;
 			__be32	dst;
 		} ipv4;
 		struct {
 			struct in6_addr src;
 			struct in6_addr dst;
 		} ipv6;
 	} u;
 	__be16			tun_flags;
 	u8			tos;		/* TOS for IPv4, TC for IPv6 */
 	u8			ttl;		/* TTL for IPv4, HL for IPv6 */
 	__be32			label;		/* Flow Label for IPv6 */
 	__be16			tp_src;
 	__be16			tp_dst;
 };

 /* Flags for ip_tunnel_info mode. */
 #define IP_TUNNEL_INFO_TX	0x01	/* represents tx tunnel parameters */
 #define IP_TUNNEL_INFO_IPV6	0x02	/* key contains IPv6 addresses */
 #define IP_TUNNEL_INFO_BRIDGE	0x04	/* represents a bridged tunnel id */

 /* Maximum tunnel options length. */
 #define IP_TUNNEL_OPTS_MAX					\
 	GENMASK((sizeof_field(struct ip_tunnel_info,		\
 			      options_len) * BITS_PER_BYTE) - 1, 0)

 struct ip_tunnel_info {
 	struct ip_tunnel_key	key;
 #ifdef CONFIG_DST_CACHE
 	struct dst_cache	dst_cache;
 #endif
 	u8			options_len;
 	u8			mode;
 };

 /* 6rd prefix/relay information */
 #ifdef CONFIG_IPV6_SIT_6RD
 struct ip_tunnel_6rd_parm {
 	struct in6_addr		prefix;
 	__be32			relay_prefix;
 	u16			prefixlen;
 	u16			relay_prefixlen;
 };
 #endif

 struct ip_tunnel_encap {
 	u16			type;
 	u16			flags;
 	__be16			sport;
 	__be16			dport;
 };

 struct ip_tunnel_prl_entry {
 	struct ip_tunnel_prl_entry __rcu *next;
 	__be32				addr;
 	u16				flags;
 	struct rcu_head			rcu_head;
 };

 struct metadata_dst;

 struct ip_tunnel {
 	struct ip_tunnel __rcu	*next;
 	struct hlist_node hash_node;
 	struct net_device	*dev;
 	struct net		*net;	/* netns for packet i/o */

 	unsigned long	err_time;	/* Time when the last ICMP error
 					 * arrived */
 	int		err_count;	/* Number of arrived ICMP errors */

 	/* These four fields used only by GRE */
 	u32		i_seqno;	/* The last seen seqno	*/
 	u32		o_seqno;	/* The last output seqno */
 	int		tun_hlen;	/* Precalculated header length */

 	/* These four fields used only by ERSPAN */
 	u32		index;		/* ERSPAN type II index */
 	u8		erspan_ver;	/* ERSPAN version */
 	u8		dir;		/* ERSPAN direction */
 	u16		hwid;		/* ERSPAN hardware ID */

 	struct dst_cache dst_cache;

 	struct ip_tunnel_parm parms;

 	int		mlink;
 	int		encap_hlen;	/* Encap header length (FOU,GUE) */
 	int		hlen;		/* tun_hlen + encap_hlen */
 	struct ip_tunnel_encap encap;

 	/* for SIT */
 #ifdef CONFIG_IPV6_SIT_6RD
 	struct ip_tunnel_6rd_parm ip6rd;
 #endif
 	struct ip_tunnel_prl_entry __rcu *prl;	/* potential router list */
 	unsigned int		prl_count;	/* # of entries in PRL */
 	unsigned int		ip_tnl_net_id;
 	struct gro_cells	gro_cells;
 	__u32			fwmark;
 	bool			collect_md;
 	bool			ignore_df;
 };

 struct tnl_ptk_info {
 	__be16 flags;
 	__be16 proto;
 	__be32 key;
 	__be32 seq;
 	int hdr_len;
 };

 #define PACKET_RCVD	0
 #define PACKET_REJECT	1
 #define PACKET_NEXT	2

 #define IP_TNL_HASH_BITS   7
 #define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)

 struct ip_tunnel_net {
 	struct net_device *fb_tunnel_dev;
 	struct rtnl_link_ops *rtnl_link_ops;
 	struct hlist_head tunnels[IP_TNL_HASH_SIZE];
 	struct ip_tunnel __rcu *collect_md_tun;
 	int type;
 };

 static inline void ip_tunnel_key_init(struct ip_tunnel_key *key,
 				      __be32 saddr, __be32 daddr,
 				      u8 tos, u8 ttl, __be32 label,
 				      __be16 tp_src, __be16 tp_dst,
 				      __be64 tun_id, __be16 tun_flags)
 {
 	key->tun_id = tun_id;
 	key->u.ipv4.src = saddr;
 	key->u.ipv4.dst = daddr;
 	memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD,
 	       0, IP_TUNNEL_KEY_IPV4_PAD_LEN);
 	key->tos = tos;
 	key->ttl = ttl;
 	key->label = label;
 	key->tun_flags = tun_flags;

 	/* For the tunnel types on the top of IPsec, the tp_src and tp_dst of
 	 * the upper tunnel are used.
 	 * E.g: GRE over IPSEC, the tp_src and tp_port are zero.
 	 */
 	key->tp_src = tp_src;
 	key->tp_dst = tp_dst;

 	/* Clear struct padding. */
 	if (sizeof(*key) != IP_TUNNEL_KEY_SIZE)
 		memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE,
 		       0, sizeof(*key) - IP_TUNNEL_KEY_SIZE);
 }

 static inline bool
 ip_tunnel_dst_cache_usable(const struct sk_buff *skb,
 			   const struct ip_tunnel_info *info)
 {
 	if (skb->mark)
 		return false;
 	if (!info)
 		return true;
 	if (info->key.tun_flags & TUNNEL_NOCACHE)
 		return false;

 	return true;
 }

 static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info
 					       *tun_info)
 {
 	return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET;
 }

 static inline __be64 key32_to_tunnel_id(__be32 key)
 {
 #ifdef __BIG_ENDIAN
 	return (__force __be64)key;
 #else
 	return (__force __be64)((__force u64)key << 32);
 #endif
 }

 /* Returns the least-significant 32 bits of a __be64. */
 static inline __be32 tunnel_id_to_key32(__be64 tun_id)
 {
 #ifdef __BIG_ENDIAN
 	return (__force __be32)tun_id;
 #else
 	return (__force __be32)((__force u64)tun_id >> 32);
 #endif
 }

 #ifdef CONFIG_INET

 static inline void ip_tunnel_init_flow(struct flowi4 *fl4,
 				       int proto,
 				       __be32 daddr, __be32 saddr,
 				       __be32 key, __u8 tos, int oif,
 				       __u32 mark, __u32 tun_inner_hash)
 {
 	memset(fl4, 0, sizeof(*fl4));
 	fl4->flowi4_oif = oif;
 	fl4->daddr = daddr;
 	fl4->saddr = saddr;
 	fl4->flowi4_tos = tos;
 	fl4->flowi4_proto = proto;
 	fl4->fl4_gre_key = key;
 	fl4->flowi4_mark = mark;
 	fl4->flowi4_multipath_hash = tun_inner_hash;
 }

 int ip_tunnel_init(struct net_device *dev);
 void ip_tunnel_uninit(struct net_device *dev);
 void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
 struct net *ip_tunnel_get_link_net(const struct net_device *dev);
 int ip_tunnel_get_iflink(const struct net_device *dev);
 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
 		       struct rtnl_link_ops *ops, char *devname);

 void ip_tunnel_delete_nets(struct list_head *list_net, unsigned int id,
 			   struct rtnl_link_ops *ops);

 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 		    const struct iphdr *tnl_params, const u8 protocol);
 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 		       const u8 proto, int tunnel_hlen);
 int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
 int ip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict);
 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);

 void ip_tunnel_get_stats64(struct net_device *dev,
 			   struct rtnl_link_stats64 *tot);
 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 				   int link, __be16 flags,
 				   __be32 remote, __be32 local,
 				   __be32 key);

 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 		  const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
 		  bool log_ecn_error);
 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
 			 struct ip_tunnel_parm *p, __u32 fwmark);
 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
 		      struct ip_tunnel_parm *p, __u32 fwmark);
 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id);

 extern const struct header_ops ip_tunnel_header_ops;
 __be16 ip_tunnel_parse_protocol(const struct sk_buff *skb);

 struct ip_tunnel_encap_ops {
 	size_t (*encap_hlen)(struct ip_tunnel_encap *e);
 	int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
 			    u8 *protocol, struct flowi4 *fl4);
 	int (*err_handler)(struct sk_buff *skb, u32 info);
 };

 #define MAX_IPTUN_ENCAP_OPS 8

 extern const struct ip_tunnel_encap_ops __rcu *
 		iptun_encaps[MAX_IPTUN_ENCAP_OPS];

 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
 			    unsigned int num);
 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
 			    unsigned int num);

 int ip_tunnel_encap_setup(struct ip_tunnel *t,
 			  struct ip_tunnel_encap *ipencap);

 static inline bool pskb_inet_may_pull(struct sk_buff *skb)
 {
 	int nhlen;

 	switch (skb->protocol) {
 #if IS_ENABLED(CONFIG_IPV6)
 	case htons(ETH_P_IPV6):
 		nhlen = sizeof(struct ipv6hdr);
 		break;
 #endif
 	case htons(ETH_P_IP):
 		nhlen = sizeof(struct iphdr);
 		break;
 	default:
 		nhlen = 0;
 	}

 	return pskb_network_may_pull(skb, nhlen);
 }

 static inline int ip_encap_hlen(struct ip_tunnel_encap *e)
 {
 	const struct ip_tunnel_encap_ops *ops;
 	int hlen = -EINVAL;

 	if (e->type == TUNNEL_ENCAP_NONE)
 		return 0;

 	if (e->type >= MAX_IPTUN_ENCAP_OPS)
 		return -EINVAL;

 	rcu_read_lock();
 	ops = rcu_dereference(iptun_encaps[e->type]);
 	if (likely(ops && ops->encap_hlen))
 		hlen = ops->encap_hlen(e);
 	rcu_read_unlock();

 	return hlen;
 }

 static inline int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t,
 				  u8 *protocol, struct flowi4 *fl4)
 {
 	const struct ip_tunnel_encap_ops *ops;
 	int ret = -EINVAL;

 	if (t->encap.type == TUNNEL_ENCAP_NONE)
 		return 0;

 	if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
 		return -EINVAL;

 	rcu_read_lock();
 	ops = rcu_dereference(iptun_encaps[t->encap.type]);
 	if (likely(ops && ops->build_header))
 		ret = ops->build_header(skb, &t->encap, protocol, fl4);
 	rcu_read_unlock();

 	return ret;
 }

 /* Extract dsfield from inner protocol */
 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
 				       const struct sk_buff *skb)
 {
 	if (skb->protocol == htons(ETH_P_IP))
 		return iph->tos;
 	else if (skb->protocol == htons(ETH_P_IPV6))
 		return ipv6_get_dsfield((const struct ipv6hdr *)iph);
 	else
 		return 0;
 }

 static inline u8 ip_tunnel_get_ttl(const struct iphdr *iph,
 				       const struct sk_buff *skb)
 {
 	if (skb->protocol == htons(ETH_P_IP))
 		return iph->ttl;
 	else if (skb->protocol == htons(ETH_P_IPV6))
 		return ((const struct ipv6hdr *)iph)->hop_limit;
 	else
 		return 0;
 }

 /* Propogate ECN bits out */
 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
 				     const struct sk_buff *skb)
 {
 	u8 inner = ip_tunnel_get_dsfield(iph, skb);

 	return INET_ECN_encapsulate(tos, inner);
 }

 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
 			   __be16 inner_proto, bool raw_proto, bool xnet);

 static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
 				       __be16 inner_proto, bool xnet)
 {
 	return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet);
 }

 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
 		   __be32 src, __be32 dst, u8 proto,
 		   u8 tos, u8 ttl, __be16 df, bool xnet);
 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md,
 					     gfp_t flags);

 int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask);

 static inline int iptunnel_pull_offloads(struct sk_buff *skb)
 {
 	if (skb_is_gso(skb)) {
 		int err;

 		err = skb_unclone(skb, GFP_ATOMIC);
 		if (unlikely(err))
 			return err;
 		skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >>
 					       NETIF_F_GSO_SHIFT);
 	}

 	skb->encapsulation = 0;
 	return 0;
 }

 static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len)
 {
 	if (pkt_len > 0) {
 		struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);

 		u64_stats_update_begin(&tstats->syncp);
 		tstats->tx_bytes += pkt_len;
 		tstats->tx_packets++;
 		u64_stats_update_end(&tstats->syncp);
 		put_cpu_ptr(tstats);
 	} else {
 		struct net_device_stats *err_stats = &dev->stats;

 		if (pkt_len < 0) {
 			err_stats->tx_errors++;
 			err_stats->tx_aborted_errors++;
 		} else {
 			err_stats->tx_dropped++;
 		}
 	}
 }

 static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info)
 {
 	return info + 1;
 }

 static inline void ip_tunnel_info_opts_get(void *to,
 					   const struct ip_tunnel_info *info)
 {
 	memcpy(to, info + 1, info->options_len);
 }

 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
 					   const void *from, int len,
 					   __be16 flags)
 {
 	memcpy(ip_tunnel_info_opts(info), from, len);
 	info->options_len = len;
 	info->key.tun_flags |= flags;
 }

 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
 {
 	return (struct ip_tunnel_info *)lwtstate->data;
 }

 DECLARE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt);

 /* Returns > 0 if metadata should be collected */
 static inline int ip_tunnel_collect_metadata(void)
 {
 	return static_branch_unlikely(&ip_tunnel_metadata_cnt);
 }

 void __init ip_tunnel_core_init(void);

 void ip_tunnel_need_metadata(void);
 void ip_tunnel_unneed_metadata(void);

 #else /* CONFIG_INET */

 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
 {
 	return NULL;
 }

 static inline void ip_tunnel_need_metadata(void)
 {
 }

 static inline void ip_tunnel_unneed_metadata(void)
 {
 }

 static inline void ip_tunnel_info_opts_get(void *to,
 					   const struct ip_tunnel_info *info)
 {
 }

 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
 					   const void *from, int len,
 					   __be16 flags)
 {
 	info->options_len = 0;
 	info->key.tun_flags |= flags;
 }

 #endif /* CONFIG_INET */

 #endif /* __NET_IP_TUNNELS_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	#ifndef __NET_IP_TUNNELS_H
	#define __NET_IP_TUNNELS_H 1

	#include <linux/if_tunnel.h>
	#include <linux/netdevice.h>
	#include <linux/skbuff.h>
	#include <linux/socket.h>
	#include <linux/types.h>
	#include <linux/u64_stats_sync.h>
	#include <linux/bitops.h>

	#include <net/dsfield.h>
	#include <net/gro_cells.h>
	#include <net/inet_ecn.h>
	#include <net/netns/generic.h>
	#include <net/rtnetlink.h>
	#include <net/lwtunnel.h>
	#include <net/dst_cache.h>

	#if IS_ENABLED(CONFIG_IPV6)
	#include <net/ipv6.h>
	#include <net/ip6_fib.h>
	#include <net/ip6_route.h>
	#endif

	/* Keep error state on tunnel for 30 sec */
	#define IPTUNNEL_ERR_TIMEO (30*HZ)

	/* Used to memset ip_tunnel padding. */
	#define IP_TUNNEL_KEY_SIZE offsetofend(struct ip_tunnel_key, tp_dst)

	/* Used to memset ipv4 address padding. */
	#define IP_TUNNEL_KEY_IPV4_PAD offsetofend(struct ip_tunnel_key, u.ipv4.dst)
	#define IP_TUNNEL_KEY_IPV4_PAD_LEN \
	(sizeof_field(struct ip_tunnel_key, u) - \
	sizeof_field(struct ip_tunnel_key, u.ipv4))

	struct ip_tunnel_key {
	__be64 tun_id;
	union {
	struct {
	__be32 src;
	__be32 dst;
	} ipv4;
	struct {
	struct in6_addr src;
	struct in6_addr dst;
	} ipv6;
	} u;
	__be16 tun_flags;
	u8 tos; /* TOS for IPv4, TC for IPv6 */
	u8 ttl; /* TTL for IPv4, HL for IPv6 */
	__be32 label; /* Flow Label for IPv6 */
	__be16 tp_src;
	__be16 tp_dst;
	};

	/* Flags for ip_tunnel_info mode. */
	#define IP_TUNNEL_INFO_TX 0x01 /* represents tx tunnel parameters */
	#define IP_TUNNEL_INFO_IPV6 0x02 /* key contains IPv6 addresses */
	#define IP_TUNNEL_INFO_BRIDGE 0x04 /* represents a bridged tunnel id */

	/* Maximum tunnel options length. */
	#define IP_TUNNEL_OPTS_MAX \
	GENMASK((sizeof_field(struct ip_tunnel_info, \
	options_len) * BITS_PER_BYTE) - 1, 0)

	struct ip_tunnel_info {
	struct ip_tunnel_key key;
	#ifdef CONFIG_DST_CACHE
	struct dst_cache dst_cache;
	#endif
	u8 options_len;
	u8 mode;
	};

	/* 6rd prefix/relay information */
	#ifdef CONFIG_IPV6_SIT_6RD
	struct ip_tunnel_6rd_parm {
	struct in6_addr prefix;
	__be32 relay_prefix;
	u16 prefixlen;
	u16 relay_prefixlen;
	};
	#endif

	struct ip_tunnel_encap {
	u16 type;
	u16 flags;
	__be16 sport;
	__be16 dport;
	};

	struct ip_tunnel_prl_entry {
	struct ip_tunnel_prl_entry __rcu *next;
	__be32 addr;
	u16 flags;
	struct rcu_head rcu_head;
	};

	struct metadata_dst;

	struct ip_tunnel {
	struct ip_tunnel __rcu *next;
	struct hlist_node hash_node;
	struct net_device *dev;
	struct net net; / netns for packet i/o */

	unsigned long err_time; /* Time when the last ICMP error
	* arrived */
	int err_count; /* Number of arrived ICMP errors */

	/* These four fields used only by GRE */
	u32 i_seqno; /* The last seen seqno */
	u32 o_seqno; /* The last output seqno */
	int tun_hlen; /* Precalculated header length */

	/* These four fields used only by ERSPAN */
	u32 index; /* ERSPAN type II index */
	u8 erspan_ver; /* ERSPAN version */
	u8 dir; /* ERSPAN direction */
	u16 hwid; /* ERSPAN hardware ID */

	struct dst_cache dst_cache;

	struct ip_tunnel_parm parms;

	int mlink;
	int encap_hlen; /* Encap header length (FOU,GUE) */
	int hlen; /* tun_hlen + encap_hlen */
	struct ip_tunnel_encap encap;

	/* for SIT */
	#ifdef CONFIG_IPV6_SIT_6RD
	struct ip_tunnel_6rd_parm ip6rd;
	#endif
	struct ip_tunnel_prl_entry __rcu prl; / potential router list */
	unsigned int prl_count; /* # of entries in PRL */
	unsigned int ip_tnl_net_id;
	struct gro_cells gro_cells;
	__u32 fwmark;
	bool collect_md;
	bool ignore_df;
	};

	struct tnl_ptk_info {
	__be16 flags;
	__be16 proto;
	__be32 key;
	__be32 seq;
	int hdr_len;
	};

	#define PACKET_RCVD 0
	#define PACKET_REJECT 1
	#define PACKET_NEXT 2

	#define IP_TNL_HASH_BITS 7
	#define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS)

	struct ip_tunnel_net {
	struct net_device *fb_tunnel_dev;
	struct rtnl_link_ops *rtnl_link_ops;
	struct hlist_head tunnels[IP_TNL_HASH_SIZE];
	struct ip_tunnel __rcu *collect_md_tun;
	int type;
	};

	static inline void ip_tunnel_key_init(struct ip_tunnel_key *key,
	__be32 saddr, __be32 daddr,
	u8 tos, u8 ttl, __be32 label,
	__be16 tp_src, __be16 tp_dst,
	__be64 tun_id, __be16 tun_flags)
	{
	key->tun_id = tun_id;
	key->u.ipv4.src = saddr;
	key->u.ipv4.dst = daddr;
	memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD,
	0, IP_TUNNEL_KEY_IPV4_PAD_LEN);
	key->tos = tos;
	key->ttl = ttl;
	key->label = label;
	key->tun_flags = tun_flags;

	/* For the tunnel types on the top of IPsec, the tp_src and tp_dst of
	* the upper tunnel are used.
	* E.g: GRE over IPSEC, the tp_src and tp_port are zero.
	*/
	key->tp_src = tp_src;
	key->tp_dst = tp_dst;

	/* Clear struct padding. */
	if (sizeof(*key) != IP_TUNNEL_KEY_SIZE)
	memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE,
	0, sizeof(*key) - IP_TUNNEL_KEY_SIZE);
	}

	static inline bool
	ip_tunnel_dst_cache_usable(const struct sk_buff *skb,
	const struct ip_tunnel_info *info)
	{
	if (skb->mark)
	return false;
	if (!info)
	return true;
	if (info->key.tun_flags & TUNNEL_NOCACHE)
	return false;

	return true;
	}

	static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info
	*tun_info)
	{
	return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET;
	}

	static inline __be64 key32_to_tunnel_id(__be32 key)
	{
	#ifdef __BIG_ENDIAN
	return (__force __be64)key;
	#else
	return (__force __be64)((__force u64)key << 32);
	#endif
	}

	/* Returns the least-significant 32 bits of a __be64. */
	static inline __be32 tunnel_id_to_key32(__be64 tun_id)
	{
	#ifdef __BIG_ENDIAN
	return (__force __be32)tun_id;
	#else
	return (__force __be32)((__force u64)tun_id >> 32);
	#endif
	}

	#ifdef CONFIG_INET

	static inline void ip_tunnel_init_flow(struct flowi4 *fl4,
	int proto,
	__be32 daddr, __be32 saddr,
	__be32 key, __u8 tos, int oif,
	__u32 mark, __u32 tun_inner_hash)
	{
	memset(fl4, 0, sizeof(*fl4));
	fl4->flowi4_oif = oif;
	fl4->daddr = daddr;
	fl4->saddr = saddr;
	fl4->flowi4_tos = tos;
	fl4->flowi4_proto = proto;
	fl4->fl4_gre_key = key;
	fl4->flowi4_mark = mark;
	fl4->flowi4_multipath_hash = tun_inner_hash;
	}

	int ip_tunnel_init(struct net_device *dev);
	void ip_tunnel_uninit(struct net_device *dev);
	void ip_tunnel_dellink(struct net_device dev, struct list_head head);
	struct net ip_tunnel_get_link_net(const struct net_device dev);
	int ip_tunnel_get_iflink(const struct net_device *dev);
	int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
	struct rtnl_link_ops ops, char devname);

	void ip_tunnel_delete_nets(struct list_head *list_net, unsigned int id,
	struct rtnl_link_ops *ops);

	void ip_tunnel_xmit(struct sk_buff skb, struct net_device dev,
	const struct iphdr *tnl_params, const u8 protocol);
	void ip_md_tunnel_xmit(struct sk_buff skb, struct net_device dev,
	const u8 proto, int tunnel_hlen);
	int ip_tunnel_ctl(struct net_device dev, struct ip_tunnel_parm p, int cmd);
	int ip_tunnel_ioctl(struct net_device dev, struct ifreq ifr, int cmd);
	int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict);
	int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);

	void ip_tunnel_get_stats64(struct net_device *dev,
	struct rtnl_link_stats64 *tot);
	struct ip_tunnel ip_tunnel_lookup(struct ip_tunnel_net itn,
	int link, __be16 flags,
	__be32 remote, __be32 local,
	__be32 key);

	int ip_tunnel_rcv(struct ip_tunnel tunnel, struct sk_buff skb,
	const struct tnl_ptk_info tpi, struct metadata_dst tun_dst,
	bool log_ecn_error);
	int ip_tunnel_changelink(struct net_device dev, struct nlattr tb[],
	struct ip_tunnel_parm *p, __u32 fwmark);
	int ip_tunnel_newlink(struct net_device dev, struct nlattr tb[],
	struct ip_tunnel_parm *p, __u32 fwmark);
	void ip_tunnel_setup(struct net_device *dev, unsigned int net_id);

	extern const struct header_ops ip_tunnel_header_ops;
	__be16 ip_tunnel_parse_protocol(const struct sk_buff *skb);

	struct ip_tunnel_encap_ops {
	size_t (encap_hlen)(struct ip_tunnel_encap e);
	int (build_header)(struct sk_buff skb, struct ip_tunnel_encap *e,
	u8 protocol, struct flowi4 fl4);
	int (err_handler)(struct sk_buff skb, u32 info);
	};

	#define MAX_IPTUN_ENCAP_OPS 8

	extern const struct ip_tunnel_encap_ops __rcu *
	iptun_encaps[MAX_IPTUN_ENCAP_OPS];

	int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
	unsigned int num);
	int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
	unsigned int num);

	int ip_tunnel_encap_setup(struct ip_tunnel *t,
	struct ip_tunnel_encap *ipencap);

	static inline bool pskb_inet_may_pull(struct sk_buff *skb)
	{
	int nhlen;

	switch (skb->protocol) {
	#if IS_ENABLED(CONFIG_IPV6)
	case htons(ETH_P_IPV6):
	nhlen = sizeof(struct ipv6hdr);
	break;
	#endif
	case htons(ETH_P_IP):
	nhlen = sizeof(struct iphdr);
	break;
	default:
	nhlen = 0;
	}

	return pskb_network_may_pull(skb, nhlen);
	}

	static inline int ip_encap_hlen(struct ip_tunnel_encap *e)
	{
	const struct ip_tunnel_encap_ops *ops;
	int hlen = -EINVAL;

	if (e->type == TUNNEL_ENCAP_NONE)
	return 0;

	if (e->type >= MAX_IPTUN_ENCAP_OPS)
	return -EINVAL;

	rcu_read_lock();
	ops = rcu_dereference(iptun_encaps[e->type]);
	if (likely(ops && ops->encap_hlen))
	hlen = ops->encap_hlen(e);
	rcu_read_unlock();

	return hlen;
	}

	static inline int ip_tunnel_encap(struct sk_buff skb, struct ip_tunnel t,
	u8 protocol, struct flowi4 fl4)
	{
	const struct ip_tunnel_encap_ops *ops;
	int ret = -EINVAL;

	if (t->encap.type == TUNNEL_ENCAP_NONE)
	return 0;

	if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
	return -EINVAL;

	rcu_read_lock();
	ops = rcu_dereference(iptun_encaps[t->encap.type]);
	if (likely(ops && ops->build_header))
	ret = ops->build_header(skb, &t->encap, protocol, fl4);
	rcu_read_unlock();

	return ret;
	}

	/* Extract dsfield from inner protocol */
	static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
	const struct sk_buff *skb)
	{
	if (skb->protocol == htons(ETH_P_IP))
	return iph->tos;
	else if (skb->protocol == htons(ETH_P_IPV6))
	return ipv6_get_dsfield((const struct ipv6hdr *)iph);
	else
	return 0;
	}

	static inline u8 ip_tunnel_get_ttl(const struct iphdr *iph,
	const struct sk_buff *skb)
	{
	if (skb->protocol == htons(ETH_P_IP))
	return iph->ttl;
	else if (skb->protocol == htons(ETH_P_IPV6))
	return ((const struct ipv6hdr *)iph)->hop_limit;
	else
	return 0;
	}

	/* Propogate ECN bits out */
	static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
	const struct sk_buff *skb)
	{
	u8 inner = ip_tunnel_get_dsfield(iph, skb);

	return INET_ECN_encapsulate(tos, inner);
	}

	int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
	__be16 inner_proto, bool raw_proto, bool xnet);

	static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
	__be16 inner_proto, bool xnet)
	{
	return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet);
	}

	void iptunnel_xmit(struct sock sk, struct rtable rt, struct sk_buff *skb,
	__be32 src, __be32 dst, u8 proto,
	u8 tos, u8 ttl, __be16 df, bool xnet);
	struct metadata_dst iptunnel_metadata_reply(struct metadata_dst md,
	gfp_t flags);

	int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask);

	static inline int iptunnel_pull_offloads(struct sk_buff *skb)
	{
	if (skb_is_gso(skb)) {
	int err;

	err = skb_unclone(skb, GFP_ATOMIC);
	if (unlikely(err))
	return err;
	skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >>
	NETIF_F_GSO_SHIFT);
	}

	skb->encapsulation = 0;
	return 0;
	}

	static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len)
	{
	if (pkt_len > 0) {
	struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);

	u64_stats_update_begin(&tstats->syncp);
	tstats->tx_bytes += pkt_len;
	tstats->tx_packets++;
	u64_stats_update_end(&tstats->syncp);
	put_cpu_ptr(tstats);
	} else {
	struct net_device_stats *err_stats = &dev->stats;

	if (pkt_len < 0) {
	err_stats->tx_errors++;
	err_stats->tx_aborted_errors++;
	} else {
	err_stats->tx_dropped++;
	}
	}
	}

	static inline void ip_tunnel_info_opts(struct ip_tunnel_info info)
	{
	return info + 1;
	}

	static inline void ip_tunnel_info_opts_get(void *to,
	const struct ip_tunnel_info *info)
	{
	memcpy(to, info + 1, info->options_len);
	}

	static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
	const void *from, int len,
	__be16 flags)
	{
	memcpy(ip_tunnel_info_opts(info), from, len);
	info->options_len = len;
	info->key.tun_flags \|= flags;
	}

	static inline struct ip_tunnel_info lwt_tun_info(struct lwtunnel_state lwtstate)
	{
	return (struct ip_tunnel_info *)lwtstate->data;
	}

	DECLARE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt);

	/* Returns > 0 if metadata should be collected */
	static inline int ip_tunnel_collect_metadata(void)
	{
	return static_branch_unlikely(&ip_tunnel_metadata_cnt);
	}

	void __init ip_tunnel_core_init(void);

	void ip_tunnel_need_metadata(void);
	void ip_tunnel_unneed_metadata(void);

	#else /* CONFIG_INET */

	static inline struct ip_tunnel_info lwt_tun_info(struct lwtunnel_state lwtstate)
	{
	return NULL;
	}

	static inline void ip_tunnel_need_metadata(void)
	{
	}

	static inline void ip_tunnel_unneed_metadata(void)
	{
	}

	static inline void ip_tunnel_info_opts_get(void *to,
	const struct ip_tunnel_info *info)
	{
	}

	static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
	const void *from, int len,
	__be16 flags)
	{
	info->options_len = 0;
	info->key.tun_flags \|= flags;
	}

	#endif /* CONFIG_INET */

	#endif /* __NET_IP_TUNNELS_H */