/* SPDX-License-Identifier: GPL-2.0 *//* * Multipath TCP * * Copyright (c) 2017 - 2019, Intel Corporation. */ #ifndef __NET_MPTCP_H#define __NET_MPTCP_H #include <linux/skbuff.h>#include <linux/tcp.h>#include <linux/types.h> struct seq_file; /* MPTCP sk_buff extension data */struct mptcp_ext {	union {		u64	data_ack;		u32	data_ack32;	};	u64		data_seq;	u32		subflow_seq;	u16		data_len;	u8		use_map:1,			dsn64:1,			data_fin:1,			use_ack:1,			ack64:1,			mpc_map:1,			__unused:2;	/* one byte hole */}; struct mptcp_out_options {#if IS_ENABLED(CONFIG_MPTCP)	u16 suboptions;	u64 sndr_key;	u64 rcvr_key;	union {		struct in_addr addr;#if IS_ENABLED(CONFIG_MPTCP_IPV6)		struct in6_addr addr6;#endif	};	u8 addr_id;	u64 ahmac;	u8 rm_id;	u8 join_id;	u8 backup;	u32 nonce;	u64 thmac;	u32 token;	u8 hmac[20];	struct mptcp_ext ext_copy;#endif}; #ifdef CONFIG_MPTCPextern struct request_sock_ops mptcp_subflow_request_sock_ops; void mptcp_init(void); static inline bool sk_is_mptcp(const struct sock *sk){	return tcp_sk(sk)->is_mptcp;} static inline bool rsk_is_mptcp(const struct request_sock *req){	return tcp_rsk(req)->is_mptcp;} static inline bool rsk_drop_req(const struct request_sock *req){	return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;} void mptcp_space(const struct sock *ssk, int *space, int *full_space);bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,		       unsigned int *size, struct mptcp_out_options *opts);bool mptcp_synack_options(const struct request_sock *req, unsigned int *size,			  struct mptcp_out_options *opts);bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,			       unsigned int *size, unsigned int remaining,			       struct mptcp_out_options *opts);void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb,			    struct tcp_options_received *opt_rx); void mptcp_write_options(__be32 *ptr, struct mptcp_out_options *opts); /* move the skb extension owership, with the assumption that 'to' is * newly allocated */static inline void mptcp_skb_ext_move(struct sk_buff *to,				      struct sk_buff *from){	if (!skb_ext_exist(from, SKB_EXT_MPTCP))		return; 	if (WARN_ON_ONCE(to->active_extensions))		skb_ext_put(to); 	to->active_extensions = from->active_extensions;	to->extensions = from->extensions;	from->active_extensions = 0;} static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,				     const struct mptcp_ext *from_ext){	/* MPTCP always clears the ext when adding it to the skb, so	 * holes do not bother us here	 */	return !from_ext ||	       (to_ext && from_ext &&	        !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));} /* check if skbs can be collapsed. * MPTCP collapse is allowed if neither @to or @from carry an mptcp data * mapping, or if the extension of @to is the same as @from. * Collapsing is not possible if @to lacks an extension, but @from carries one. */static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,					  const struct sk_buff *from){	return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),				 skb_ext_find(from, SKB_EXT_MPTCP));} void mptcp_seq_show(struct seq_file *seq);int mptcp_subflow_init_cookie_req(struct request_sock *req,				  const struct sock *sk_listener,				  struct sk_buff *skb);#else static inline void mptcp_init(void){} static inline bool sk_is_mptcp(const struct sock *sk){	return false;} static inline bool rsk_is_mptcp(const struct request_sock *req){	return false;} static inline bool rsk_drop_req(const struct request_sock *req){	return false;} static inline void mptcp_parse_option(const struct sk_buff *skb,				      const unsigned char *ptr, int opsize,				      struct tcp_options_received *opt_rx){} static inline bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,				     unsigned int *size,				     struct mptcp_out_options *opts){	return false;} static inline bool mptcp_synack_options(const struct request_sock *req,					unsigned int *size,					struct mptcp_out_options *opts){	return false;} static inline bool mptcp_established_options(struct sock *sk,					     struct sk_buff *skb,					     unsigned int *size,					     unsigned int remaining,					     struct mptcp_out_options *opts){	return false;} static inline void mptcp_incoming_options(struct sock *sk,					  struct sk_buff *skb,					  struct tcp_options_received *opt_rx){} static inline void mptcp_skb_ext_move(struct sk_buff *to,				      const struct sk_buff *from){} static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,					  const struct sk_buff *from){	return true;} static inline void mptcp_space(const struct sock *ssk, int *s, int *fs) { }static inline void mptcp_seq_show(struct seq_file *seq) { } static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,						const struct sock *sk_listener,						struct sk_buff *skb){	return 0; /* TCP fallback */}#endif /* CONFIG_MPTCP */ #if IS_ENABLED(CONFIG_MPTCP_IPV6)int mptcpv6_init(void);void mptcpv6_handle_mapped(struct sock *sk, bool mapped);#elif IS_ENABLED(CONFIG_IPV6)static inline int mptcpv6_init(void) { return 0; }static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }#endif #endif /* __NET_MPTCP_H */