[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;
	__sum16		csum;
	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,
			csum_reqd:1;
};

#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,
	   reset_transient:1,
	   csum_reqd: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;
d0cc2987	26	__sum16 csum;
3ee17bc7 MM	27	u8 use_map:1,
	28	dsn64:1,
	29	data_fin:1,
	30	use_ack:1,
	31	ack64:1,
cc7972ea	32	mpc_map:1,
5a369ca6	33	frozen:1,
dc87efdb	34	reset_transient:1;
208e8f66 GT	35	u8 reset_reason:4,
208e8f66 GT	36	csum_reqd:1;
3ee17bc7 MM	37	};
3ee17bc7 MM	38
6445e17a GT	39	#define MPTCP_RM_IDS_MAX 8
	40
	41	struct mptcp_rm_list {
	42	u8 ids[MPTCP_RM_IDS_MAX];
	43	u8 nr;
	44	};
	45
30f60bae GT	46	struct mptcp_addr_info {
	47	u8 id;
	48	sa_family_t family;
	49	__be16 port;
	50	union {
	51	struct in_addr addr;
	52	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	53	struct in6_addr addr6;
	54	#endif
	55	};
	56	};
	57
eda7acdd PK	58	struct mptcp_out_options {
	59	#if IS_ENABLED(CONFIG_MPTCP)
	60	u16 suboptions;
	61	u64 sndr_key;
	62	u64 rcvr_key;
3df523ab	63	u64 ahmac;
30f60bae	64	struct mptcp_addr_info addr;
6445e17a	65	struct mptcp_rm_list rm_list;
f296234c PK	66	u8 join_id;
f296234c PK	67	u8 backup;
06fe1719 GT	68	u8 reset_reason:4,
	69	reset_transient:1,
	70	csum_reqd:1;
f296234c PK	71	u32 nonce;
f296234c PK	72	u64 thmac;
ec3edaa7 PK	73	u32 token;
ec3edaa7 PK	74	u8 hmac[20];
6d0060f6	75	struct mptcp_ext ext_copy;
eda7acdd PK	76	#endif
	77	};
	78
85712484	79	#ifdef CONFIG_MPTCP
08b8d080	80	extern struct request_sock_ops mptcp_subflow_request_sock_ops;
85712484	81
f870fa0b MM	82	void mptcp_init(void);
f870fa0b MM	83
cec37a6e PK	84	static inline bool sk_is_mptcp(const struct sock *sk)
	85	{
	86	return tcp_sk(sk)->is_mptcp;
	87	}
	88
	89	static inline bool rsk_is_mptcp(const struct request_sock *req)
	90	{
	91	return tcp_rsk(req)->is_mptcp;
	92	}
	93
90bf4513 PA	94	static inline bool rsk_drop_req(const struct request_sock *req)
	95	{
	96	return tcp_rsk(req)->is_mptcp && tcp_rsk(req)->drop_req;
	97	}
	98
071c8ed6	99	void mptcp_space(const struct sock ssk, int space, int *full_space);
cc7972ea CP	100	bool mptcp_syn_options(struct sock sk, const struct sk_buff skb,
cc7972ea CP	101	unsigned int size, struct mptcp_out_options opts);
cec37a6e PK	102	bool mptcp_synack_options(const struct request_sock req, unsigned int size,
	103	struct mptcp_out_options *opts);
	104	bool mptcp_established_options(struct sock sk, struct sk_buff skb,
	105	unsigned int *size, unsigned int remaining,
	106	struct mptcp_out_options *opts);
77d0cab9	107	void mptcp_incoming_options(struct sock sk, struct sk_buff skb);
cec37a6e	108
fa3fe2b1 FW	109	void mptcp_write_options(__be32 ptr, const struct tcp_sock tp,
fa3fe2b1 FW	110	struct mptcp_out_options *opts);
eda7acdd	111
85712484 MM	112	/* move the skb extension owership, with the assumption that 'to' is
	113	* newly allocated
	114	*/
	115	static inline void mptcp_skb_ext_move(struct sk_buff *to,
	116	struct sk_buff *from)
	117	{
	118	if (!skb_ext_exist(from, SKB_EXT_MPTCP))
	119	return;
	120
	121	if (WARN_ON_ONCE(to->active_extensions))
	122	skb_ext_put(to);
	123
	124	to->active_extensions = from->active_extensions;
	125	to->extensions = from->extensions;
	126	from->active_extensions = 0;
	127	}
	128
5a369ca6 PA	129	static inline void mptcp_skb_ext_copy(struct sk_buff *to,
	130	struct sk_buff *from)
	131	{
	132	struct mptcp_ext *from_ext;
	133
	134	from_ext = skb_ext_find(from, SKB_EXT_MPTCP);
	135	if (!from_ext)
	136	return;
	137
	138	from_ext->frozen = 1;
	139	skb_ext_copy(to, from);
	140	}
	141
85712484 MM	142	static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext,
	143	const struct mptcp_ext *from_ext)
	144	{
	145	/* MPTCP always clears the ext when adding it to the skb, so
	146	* holes do not bother us here
	147	*/
	148	return !from_ext \|\|
	149	(to_ext && from_ext &&
	150	!memcmp(from_ext, to_ext, sizeof(struct mptcp_ext)));
	151	}
	152
	153	/* check if skbs can be collapsed.
	154	* MPTCP collapse is allowed if neither @to or @from carry an mptcp data
	155	* mapping, or if the extension of @to is the same as @from.
	156	* Collapsing is not possible if @to lacks an extension, but @from carries one.
	157	*/
	158	static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
	159	const struct sk_buff *from)
	160	{
	161	return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP),
	162	skb_ext_find(from, SKB_EXT_MPTCP));
	163	}
	164
fc518953	165	void mptcp_seq_show(struct seq_file *seq);
c83a47e5 FW	166	int mptcp_subflow_init_cookie_req(struct request_sock *req,
	167	const struct sock *sk_listener,
	168	struct sk_buff *skb);
dc87efdb FW	169
	170	__be32 mptcp_get_reset_option(const struct sk_buff *skb);
	171
	172	static inline __be32 mptcp_reset_option(const struct sk_buff *skb)
	173	{
	174	if (skb_ext_exist(skb, SKB_EXT_MPTCP))
	175	return mptcp_get_reset_option(skb);
	176
	177	return htonl(0u);
	178	}
85712484 MM	179	#else
85712484 MM	180
f870fa0b MM	181	static inline void mptcp_init(void)
	182	{
	183	}
	184
cec37a6e PK	185	static inline bool sk_is_mptcp(const struct sock *sk)
	186	{
	187	return false;
	188	}
	189
	190	static inline bool rsk_is_mptcp(const struct request_sock *req)
	191	{
	192	return false;
	193	}
	194
90bf4513 PA	195	static inline bool rsk_drop_req(const struct request_sock *req)
	196	{
	197	return false;
	198	}
	199
cc7972ea CP	200	static inline void mptcp_parse_option(const struct sk_buff *skb,
cc7972ea CP	201	const unsigned char *ptr, int opsize,
eda7acdd PK	202	struct tcp_options_received *opt_rx)
	203	{
	204	}
	205
cc7972ea CP	206	static inline bool mptcp_syn_options(struct sock sk, const struct sk_buff skb,
cc7972ea CP	207	unsigned int *size,
cec37a6e PK	208	struct mptcp_out_options *opts)
	209	{
	210	return false;
	211	}
	212
cec37a6e PK	213	static inline bool mptcp_synack_options(const struct request_sock *req,
	214	unsigned int *size,
	215	struct mptcp_out_options *opts)
	216	{
	217	return false;
	218	}
	219
	220	static inline bool mptcp_established_options(struct sock *sk,
	221	struct sk_buff *skb,
	222	unsigned int *size,
	223	unsigned int remaining,
	224	struct mptcp_out_options *opts)
	225	{
	226	return false;
	227	}
	228
648ef4b8	229	static inline void mptcp_incoming_options(struct sock *sk,
77d0cab9	230	struct sk_buff *skb)
648ef4b8 MM	231	{
	232	}
	233
85712484 MM	234	static inline void mptcp_skb_ext_move(struct sk_buff *to,
	235	const struct sk_buff *from)
	236	{
	237	}
	238
5a369ca6 PA	239	static inline void mptcp_skb_ext_copy(struct sk_buff *to,
	240	struct sk_buff *from)
	241	{
	242	}
	243
85712484 MM	244	static inline bool mptcp_skb_can_collapse(const struct sk_buff *to,
	245	const struct sk_buff *from)
	246	{
	247	return true;
	248	}
	249
071c8ed6	250	static inline void mptcp_space(const struct sock ssk, int s, int *fs) { }
fc518953	251	static inline void mptcp_seq_show(struct seq_file *seq) { }
c83a47e5 FW	252
	253	static inline int mptcp_subflow_init_cookie_req(struct request_sock *req,
	254	const struct sock *sk_listener,
	255	struct sk_buff *skb)
	256	{
	257	return 0; /* TCP fallback */
	258	}
dc87efdb FW	259
dc87efdb FW	260	static inline __be32 mptcp_reset_option(const struct sk_buff *skb) { return htonl(0u); }
85712484	261	#endif /* CONFIG_MPTCP */
f870fa0b MM	262
	263	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	264	int mptcpv6_init(void);
31484d56	265	void mptcpv6_handle_mapped(struct sock *sk, bool mapped);
f870fa0b	266	#elif IS_ENABLED(CONFIG_IPV6)
31484d56 GU	267	static inline int mptcpv6_init(void) { return 0; }
31484d56 GU	268	static inline void mptcpv6_handle_mapped(struct sock *sk, bool mapped) { }
f870fa0b MM	269	#endif
f870fa0b MM	270
3ee17bc7	271	#endif /* __NET_MPTCP_H */