[linux-block.git] / include / net / mptcp.h

/* 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>

/* MPTCP sk_buff extension data */
struct mptcp_ext {
	u64		data_ack;
	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;
	struct mptcp_ext ext_copy;
#endif
};

#ifdef CONFIG_MPTCP

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;
}

void mptcp_parse_option(const struct sk_buff *skb, const unsigned char *ptr,
			int opsize, struct tcp_options_received *opt_rx);
bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
		       unsigned int *size, struct mptcp_out_options *opts);
void mptcp_rcv_synsent(struct sock *sk);
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));
}

#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 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 void mptcp_rcv_synsent(struct sock *sk)
{
}

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;
}

#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 */
Commit	Line	Data
3ee17bc7 MM	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	/*
	3	* Multipath TCP
	4	*
	5	* Copyright (c) 2017 - 2019, Intel Corporation.
	6	*/
	7
	8	#ifndef __NET_MPTCP_H
	9	#define __NET_MPTCP_H
	10
85712484	11	#include <linux/skbuff.h>
eda7acdd	12	#include <linux/tcp.h>
3ee17bc7 MM	13	#include <linux/types.h>
	14
	15	/* MPTCP sk_buff extension data */
	16	struct mptcp_ext {
	17	u64 data_ack;
	18	u64 data_seq;
	19	u32 subflow_seq;
	20	u16 data_len;
	21	u8 use_map:1,
	22	dsn64:1,
	23	data_fin:1,
	24	use_ack:1,
	25	ack64:1,
cc7972ea CP	26	mpc_map:1,
cc7972ea CP	27	__unused:2;
3ee17bc7 MM	28	/* one byte hole */
	29	};
	30
eda7acdd PK	31	struct mptcp_out_options {
	32	#if IS_ENABLED(CONFIG_MPTCP)
	33	u16 suboptions;
	34	u64 sndr_key;
	35	u64 rcvr_key;
3df523ab PK	36	union {
	37	struct in_addr addr;
	38	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	39	struct in6_addr addr6;
	40	#endif
	41	};
	42	u8 addr_id;
	43	u64 ahmac;
	44	u8 rm_id;
6d0060f6	45	struct mptcp_ext ext_copy;
eda7acdd PK	46	#endif
	47	};
	48
85712484 MM	49	#ifdef CONFIG_MPTCP
85712484 MM	50
f870fa0b MM	51	void mptcp_init(void);
f870fa0b MM	52
cec37a6e PK	53	static inline bool sk_is_mptcp(const struct sock *sk)
	54	{
	55	return tcp_sk(sk)->is_mptcp;
	56	}
	57
	58	static inline bool rsk_is_mptcp(const struct request_sock *req)
	59	{
	60	return tcp_rsk(req)->is_mptcp;
	61	}
	62
cc7972ea CP	63	void mptcp_parse_option(const struct sk_buff skb, const unsigned char ptr,
	64	int opsize, struct tcp_options_received *opt_rx);
	65	bool mptcp_syn_options(struct sock sk, const struct sk_buff skb,
	66	unsigned int size, struct mptcp_out_options opts);
cec37a6e PK	67	void mptcp_rcv_synsent(struct sock *sk);
	68	bool mptcp_synack_options(const struct request_sock req, unsigned int size,
	69	struct mptcp_out_options *opts);
	70	bool mptcp_established_options(struct sock sk, struct sk_buff skb,
	71	unsigned int *size, unsigned int remaining,
	72	struct mptcp_out_options *opts);
648ef4b8 MM	73	void mptcp_incoming_options(struct sock sk, struct sk_buff skb,
648ef4b8 MM	74	struct tcp_options_received *opt_rx);
cec37a6e	75
eda7acdd PK	76	void mptcp_write_options(__be32 ptr, struct mptcp_out_options opts);
eda7acdd PK	77
85712484 MM	78	/* move the skb extension owership, with the assumption that 'to' is
	79	* newly allocated
	80	*/
	81	static inline void mptcp_skb_ext_move(struct sk_buff *to,
	82	struct sk_buff *from)
	83	{
	84	if (!skb_ext_exist(from, SKB_EXT_MPTCP))
	85	return;
	86
	87	if (WARN_ON_ONCE(to->active_extensions))
	88	skb_ext_put(to);
	89
	90	to->active_extensions = from->active_extensions;
	91	to->extensions = from->extensions;
	92	from->active_extensions = 0;
	93	}
	94
	95	static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
	96	const struct mptcp_ext *from_ext)
	97	{
	98	/* MPTCP always clears the ext when adding it to the skb, so
	99	* holes do not bother us here
	100	*/
	101	return !from_ext \|\|
	102	(to_ext && from_ext &&
	103	!memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
	104	}
	105
	106	/* check if skbs can be collapsed.
	107	* MPTCP collapse is allowed if neither @to or @from carry an mptcp data
	108	* mapping, or if the extension of @to is the same as @from.
	109	* Collapsing is not possible if @to lacks an extension, but @from carries one.
	110	*/
	111	static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
	112	const struct sk_buff *from)
	113	{
	114	return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
	115	skb_ext_find(from, SKB_EXT_MPTCP));
	116	}
	117
	118	#else
	119
f870fa0b MM	120	static inline void mptcp_init(void)
	121	{
	122	}
	123
cec37a6e PK	124	static inline bool sk_is_mptcp(const struct sock *sk)
	125	{
	126	return false;
	127	}
	128
	129	static inline bool rsk_is_mptcp(const struct request_sock *req)
	130	{
	131	return false;
	132	}
	133
cc7972ea CP	134	static inline void mptcp_parse_option(const struct sk_buff *skb,
cc7972ea CP	135	const unsigned char *ptr, int opsize,
eda7acdd PK	136	struct tcp_options_received *opt_rx)
	137	{
	138	}
	139
cc7972ea CP	140	static inline bool mptcp_syn_options(struct sock sk, const struct sk_buff skb,
cc7972ea CP	141	unsigned int *size,
cec37a6e PK	142	struct mptcp_out_options *opts)
	143	{
	144	return false;
	145	}
	146
	147	static inline void mptcp_rcv_synsent(struct sock *sk)
	148	{
	149	}
	150
	151	static inline bool mptcp_synack_options(const struct request_sock *req,
	152	unsigned int *size,
	153	struct mptcp_out_options *opts)
	154	{
	155	return false;
	156	}
	157
	158	static inline bool mptcp_established_options(struct sock *sk,
	159	struct sk_buff *skb,
	160	unsigned int *size,
	161	unsigned int remaining,
	162	struct mptcp_out_options *opts)
	163	{
	164	return false;
	165	}
	166
648ef4b8 MM	167	static inline void mptcp_incoming_options(struct sock *sk,
	168	struct sk_buff *skb,
	169	struct tcp_options_received *opt_rx)
	170	{
	171	}
	172
85712484 MM	173	static inline void mptcp_skb_ext_move(struct sk_buff *to,
	174	const struct sk_buff *from)
	175	{
	176	}
	177
	178	static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
	179	const struct sk_buff *from)
	180	{
	181	return true;
	182	}
	183
	184	#endif /* CONFIG_MPTCP */
f870fa0b MM	185
	186	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	187	int mptcpv6_init(void);
31484d56	188	void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
f870fa0b	189	#elif IS_ENABLED(CONFIG_IPV6)
31484d56 GU	190	static inline int mptcpv6_init(void) { return 0; }
31484d56 GU	191	static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
f870fa0b MM	192	#endif
f870fa0b MM	193
3ee17bc7	194	#endif /* __NET_MPTCP_H */