[mirror_ubuntu-jammy-kernel.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>

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,
			frozen:1,
			reset_transient:1;
	u8		reset_reason:4;
};

#define MPTCP_RM_IDS_MAX	8

struct mptcp_rm_list {
	u8 ids[MPTCP_RM_IDS_MAX];
	u8 nr;
};

struct mptcp_addr_info {
	u8			id;
	sa_family_t		family;
	__be16			port;
	union {
		struct in_addr	addr;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
		struct in6_addr	addr6;
#endif
	};
};

struct mptcp_out_options {
#if IS_ENABLED(CONFIG_MPTCP)
	u16 suboptions;
	u64 sndr_key;
	u64 rcvr_key;
	u64 ahmac;
	struct mptcp_addr_info addr;
	struct mptcp_rm_list rm_list;
	u8 join_id;
	u8 backup;
	u8 reset_reason:4;
	u8 reset_transient:1;
	u32 nonce;
	u64 thmac;
	u32 token;
	u8 hmac[20];
	struct mptcp_ext ext_copy;
#endif
};

#ifdef CONFIG_MPTCP
extern 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);

void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
			 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 void mptcp_skb_ext_copy(struct sk_buff *to,
				      struct sk_buff *from)
{
	struct mptcp_ext *from_ext;

	from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
	if (!from_ext)
		return;

	from_ext->frozen = 1;
	skb_ext_copy(to, from);
}

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);

__be32 mptcp_get_reset_option(const struct sk_buff *skb);

static inline __be32 mptcp_reset_option(const struct sk_buff *skb)
{
	if (skb_ext_exist(skb, SKB_EXT_MPTCP))
		return mptcp_get_reset_option(skb);

	return htonl(0u);
}
#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)
{
}

static inline void mptcp_skb_ext_move(struct sk_buff *to,
				      const struct sk_buff *from)
{
}

static inline void mptcp_skb_ext_copy(struct sk_buff *to,
				      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 */
}

static inline __be32 mptcp_reset_option(const struct sk_buff *skb)  { return htonl(0u); }
#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>
3ee17bc7 MM	14
fc518953 FW	15	struct seq_file;
fc518953 FW	16
3ee17bc7 MM	17	/* MPTCP sk_buff extension data */
3ee17bc7 MM	18	struct mptcp_ext {
a0c1d0ea CP	19	union {
	20	u64 data_ack;
	21	u32 data_ack32;
	22	};
3ee17bc7 MM	23	u64 data_seq;
	24	u32 subflow_seq;
	25	u16 data_len;
	26	u8 use_map:1,
	27	dsn64:1,
	28	data_fin:1,
	29	use_ack:1,
	30	ack64:1,
cc7972ea	31	mpc_map:1,
5a369ca6	32	frozen:1,
dc87efdb FW	33	reset_transient:1;
dc87efdb FW	34	u8 reset_reason:4;
3ee17bc7 MM	35	};
3ee17bc7 MM	36
6445e17a GT	37	#define MPTCP_RM_IDS_MAX 8
	38
	39	struct mptcp_rm_list {
	40	u8 ids[MPTCP_RM_IDS_MAX];
	41	u8 nr;
	42	};
	43
30f60bae GT	44	struct mptcp_addr_info {
	45	u8 id;
	46	sa_family_t family;
	47	__be16 port;
	48	union {
	49	struct in_addr addr;
	50	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	51	struct in6_addr addr6;
	52	#endif
	53	};
	54	};
	55
eda7acdd PK	56	struct mptcp_out_options {
	57	#if IS_ENABLED(CONFIG_MPTCP)
	58	u16 suboptions;
	59	u64 sndr_key;
	60	u64 rcvr_key;
3df523ab	61	u64 ahmac;
30f60bae	62	struct mptcp_addr_info addr;
6445e17a	63	struct mptcp_rm_list rm_list;
f296234c PK	64	u8 join_id;
f296234c PK	65	u8 backup;
dc87efdb FW	66	u8 reset_reason:4;
dc87efdb FW	67	u8 reset_transient:1;
f296234c PK	68	u32 nonce;
f296234c PK	69	u64 thmac;
ec3edaa7 PK	70	u32 token;
ec3edaa7 PK	71	u8 hmac[20];
6d0060f6	72	struct mptcp_ext ext_copy;
eda7acdd PK	73	#endif
	74	};
	75
85712484	76	#ifdef CONFIG_MPTCP
08b8d080	77	extern struct request_sock_ops mptcp_subflow_request_sock_ops;
85712484	78
f870fa0b MM	79	void mptcp_init(void);
f870fa0b MM	80
cec37a6e PK	81	static inline bool sk_is_mptcp(const struct sock *sk)
	82	{
	83	return tcp_sk(sk)->is_mptcp;
	84	}
	85
	86	static inline bool rsk_is_mptcp(const struct request_sock *req)
	87	{
	88	return tcp_rsk(req)->is_mptcp;
	89	}
	90
90bf4513 PA	91	static inline bool rsk_drop_req(const struct request_sock *req)
	92	{
	93	return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
	94	}
	95
071c8ed6	96	void mptcp_space(const struct sock ssk, int space, int *full_space);
cc7972ea CP	97	bool mptcp_syn_options(struct sock sk, const struct sk_buff skb,
cc7972ea CP	98	unsigned int size, struct mptcp_out_options opts);
cec37a6e PK	99	bool mptcp_synack_options(const struct request_sock req, unsigned int size,
	100	struct mptcp_out_options *opts);
	101	bool mptcp_established_options(struct sock sk, struct sk_buff skb,
	102	unsigned int *size, unsigned int remaining,
	103	struct mptcp_out_options *opts);
77d0cab9	104	void mptcp_incoming_options(struct sock sk, struct sk_buff skb);
cec37a6e	105
fa3fe2b1 FW	106	void mptcp_write_options(__be32 ptr, const struct tcp_sock tp,
fa3fe2b1 FW	107	struct mptcp_out_options *opts);
eda7acdd	108
85712484 MM	109	/* move the skb extension owership, with the assumption that 'to' is
	110	* newly allocated
	111	*/
	112	static inline void mptcp_skb_ext_move(struct sk_buff *to,
	113	struct sk_buff *from)
	114	{
	115	if (!skb_ext_exist(from, SKB_EXT_MPTCP))
	116	return;
	117
	118	if (WARN_ON_ONCE(to->active_extensions))
	119	skb_ext_put(to);
	120
	121	to->active_extensions = from->active_extensions;
	122	to->extensions = from->extensions;
	123	from->active_extensions = 0;
	124	}
	125
5a369ca6 PA	126	static inline void mptcp_skb_ext_copy(struct sk_buff *to,
	127	struct sk_buff *from)
	128	{
	129	struct mptcp_ext *from_ext;
	130
	131	from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
	132	if (!from_ext)
	133	return;
	134
	135	from_ext->frozen = 1;
	136	skb_ext_copy(to, from);
	137	}
	138
85712484 MM	139	static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
	140	const struct mptcp_ext *from_ext)
	141	{
	142	/* MPTCP always clears the ext when adding it to the skb, so
	143	* holes do not bother us here
	144	*/
	145	return !from_ext \|\|
	146	(to_ext && from_ext &&
	147	!memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
	148	}
	149
	150	/* check if skbs can be collapsed.
	151	* MPTCP collapse is allowed if neither @to or @from carry an mptcp data
	152	* mapping, or if the extension of @to is the same as @from.
	153	* Collapsing is not possible if @to lacks an extension, but @from carries one.
	154	*/
	155	static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
	156	const struct sk_buff *from)
	157	{
	158	return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
	159	skb_ext_find(from, SKB_EXT_MPTCP));
	160	}
	161
fc518953	162	void mptcp_seq_show(struct seq_file *seq);
c83a47e5 FW	163	int mptcp_subflow_init_cookie_req(struct request_sock *req,
	164	const struct sock *sk_listener,
	165	struct sk_buff *skb);
dc87efdb FW	166
	167	__be32 mptcp_get_reset_option(const struct sk_buff *skb);
	168
	169	static inline __be32 mptcp_reset_option(const struct sk_buff *skb)
	170	{
	171	if (skb_ext_exist(skb, SKB_EXT_MPTCP))
	172	return mptcp_get_reset_option(skb);
	173
	174	return htonl(0u);
	175	}
85712484 MM	176	#else
85712484 MM	177
f870fa0b MM	178	static inline void mptcp_init(void)
	179	{
	180	}
	181
cec37a6e PK	182	static inline bool sk_is_mptcp(const struct sock *sk)
	183	{
	184	return false;
	185	}
	186
	187	static inline bool rsk_is_mptcp(const struct request_sock *req)
	188	{
	189	return false;
	190	}
	191
90bf4513 PA	192	static inline bool rsk_drop_req(const struct request_sock *req)
	193	{
	194	return false;
	195	}
	196
cc7972ea CP	197	static inline void mptcp_parse_option(const struct sk_buff *skb,
cc7972ea CP	198	const unsigned char *ptr, int opsize,
eda7acdd PK	199	struct tcp_options_received *opt_rx)
	200	{
	201	}
	202
cc7972ea CP	203	static inline bool mptcp_syn_options(struct sock sk, const struct sk_buff skb,
cc7972ea CP	204	unsigned int *size,
cec37a6e PK	205	struct mptcp_out_options *opts)
	206	{
	207	return false;
	208	}
	209
cec37a6e PK	210	static inline bool mptcp_synack_options(const struct request_sock *req,
	211	unsigned int *size,
	212	struct mptcp_out_options *opts)
	213	{
	214	return false;
	215	}
	216
	217	static inline bool mptcp_established_options(struct sock *sk,
	218	struct sk_buff *skb,
	219	unsigned int *size,
	220	unsigned int remaining,
	221	struct mptcp_out_options *opts)
	222	{
	223	return false;
	224	}
	225
648ef4b8	226	static inline void mptcp_incoming_options(struct sock *sk,
77d0cab9	227	struct sk_buff *skb)
648ef4b8 MM	228	{
	229	}
	230
85712484 MM	231	static inline void mptcp_skb_ext_move(struct sk_buff *to,
	232	const struct sk_buff *from)
	233	{
	234	}
	235
5a369ca6 PA	236	static inline void mptcp_skb_ext_copy(struct sk_buff *to,
	237	struct sk_buff *from)
	238	{
	239	}
	240
85712484 MM	241	static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
	242	const struct sk_buff *from)
	243	{
	244	return true;
	245	}
	246
071c8ed6	247	static inline void mptcp_space(const struct sock ssk, int s, int *fs) { }
fc518953	248	static inline void mptcp_seq_show(struct seq_file *seq) { }
c83a47e5 FW	249
	250	static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
	251	const struct sock *sk_listener,
	252	struct sk_buff *skb)
	253	{
	254	return 0; /* TCP fallback */
	255	}
dc87efdb FW	256
dc87efdb FW	257	static inline __be32 mptcp_reset_option(const struct sk_buff *skb) { return htonl(0u); }
85712484	258	#endif /* CONFIG_MPTCP */
f870fa0b MM	259
	260	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	261	int mptcpv6_init(void);
31484d56	262	void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
f870fa0b	263	#elif IS_ENABLED(CONFIG_IPV6)
31484d56 GU	264	static inline int mptcpv6_init(void) { return 0; }
31484d56 GU	265	static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
f870fa0b MM	266	#endif
f870fa0b MM	267
3ee17bc7	268	#endif /* __NET_MPTCP_H */