1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Multipath TCP
3 *
4 * Copyright (c) 2017 - 2019, Intel Corporation.
5 */
6
7 #ifndef __MPTCP_PROTOCOL_H
8 #define __MPTCP_PROTOCOL_H
9
10 #include <linux/random.h>
11 #include <net/tcp.h>
12 #include <net/inet_connection_sock.h>
13 #include <uapi/linux/mptcp.h>
14 #include <net/genetlink.h>
15 #include <net/rstreason.h>
16
17 #define MPTCP_SUPPORTED_VERSION 1
18
19 /* MPTCP option bits */
20 #define OPTION_MPTCP_MPC_SYN BIT(0)
21 #define OPTION_MPTCP_MPC_SYNACK BIT(1)
22 #define OPTION_MPTCP_MPC_ACK BIT(2)
23 #define OPTION_MPTCP_MPJ_SYN BIT(3)
24 #define OPTION_MPTCP_MPJ_SYNACK BIT(4)
25 #define OPTION_MPTCP_MPJ_ACK BIT(5)
26 #define OPTION_MPTCP_ADD_ADDR BIT(6)
27 #define OPTION_MPTCP_RM_ADDR BIT(7)
28 #define OPTION_MPTCP_FASTCLOSE BIT(8)
29 #define OPTION_MPTCP_PRIO BIT(9)
30 #define OPTION_MPTCP_RST BIT(10)
31 #define OPTION_MPTCP_DSS BIT(11)
32 #define OPTION_MPTCP_FAIL BIT(12)
33
34 #define OPTION_MPTCP_CSUMREQD BIT(13)
35
36 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \
37 OPTION_MPTCP_MPC_ACK)
38 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \
39 OPTION_MPTCP_MPJ_ACK)
40
41 /* MPTCP option subtypes */
42 #define MPTCPOPT_MP_CAPABLE 0
43 #define MPTCPOPT_MP_JOIN 1
44 #define MPTCPOPT_DSS 2
45 #define MPTCPOPT_ADD_ADDR 3
46 #define MPTCPOPT_RM_ADDR 4
47 #define MPTCPOPT_MP_PRIO 5
48 #define MPTCPOPT_MP_FAIL 6
49 #define MPTCPOPT_MP_FASTCLOSE 7
50 #define MPTCPOPT_RST 8
51
52 /* MPTCP suboption lengths */
53 #define TCPOLEN_MPTCP_MPC_SYN 4
54 #define TCPOLEN_MPTCP_MPC_SYNACK 12
55 #define TCPOLEN_MPTCP_MPC_ACK 20
56 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22
57 #define TCPOLEN_MPTCP_MPJ_SYN 12
58 #define TCPOLEN_MPTCP_MPJ_SYNACK 16
59 #define TCPOLEN_MPTCP_MPJ_ACK 24
60 #define TCPOLEN_MPTCP_DSS_BASE 4
61 #define TCPOLEN_MPTCP_DSS_ACK32 4
62 #define TCPOLEN_MPTCP_DSS_ACK64 8
63 #define TCPOLEN_MPTCP_DSS_MAP32 10
64 #define TCPOLEN_MPTCP_DSS_MAP64 14
65 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2
66 #define TCPOLEN_MPTCP_ADD_ADDR 16
67 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18
68 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8
69 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10
70 #define TCPOLEN_MPTCP_ADD_ADDR6 28
71 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30
72 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20
73 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22
74 #define TCPOLEN_MPTCP_PORT_LEN 2
75 #define TCPOLEN_MPTCP_PORT_ALIGN 2
76 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3
77 #define TCPOLEN_MPTCP_PRIO 3
78 #define TCPOLEN_MPTCP_PRIO_ALIGN 4
79 #define TCPOLEN_MPTCP_FASTCLOSE 12
80 #define TCPOLEN_MPTCP_RST 4
81 #define TCPOLEN_MPTCP_FAIL 12
82
83 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA)
84
85 /* MPTCP MP_JOIN flags */
86 #define MPTCPOPT_BACKUP BIT(0)
87 #define MPTCPOPT_THMAC_LEN 8
88
89 /* MPTCP MP_CAPABLE flags */
90 #define MPTCP_VERSION_MASK (0x0F)
91 #define MPTCP_CAP_CHECKSUM_REQD BIT(7)
92 #define MPTCP_CAP_EXTENSIBILITY BIT(6)
93 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5)
94 #define MPTCP_CAP_HMAC_SHA256 BIT(0)
95 #define MPTCP_CAP_FLAG_MASK (0x1F)
96
97 /* MPTCP DSS flags */
98 #define MPTCP_DSS_DATA_FIN BIT(4)
99 #define MPTCP_DSS_DSN64 BIT(3)
100 #define MPTCP_DSS_HAS_MAP BIT(2)
101 #define MPTCP_DSS_ACK64 BIT(1)
102 #define MPTCP_DSS_HAS_ACK BIT(0)
103 #define MPTCP_DSS_FLAG_MASK (0x1F)
104
105 /* MPTCP ADD_ADDR flags */
106 #define MPTCP_ADDR_ECHO BIT(0)
107
108 /* MPTCP MP_PRIO flags */
109 #define MPTCP_PRIO_BKUP BIT(0)
110
111 /* MPTCP TCPRST flags */
112 #define MPTCP_RST_TRANSIENT BIT(0)
113
114 /* MPTCP socket atomic flags */
115 #define MPTCP_WORK_RTX 1
116 #define MPTCP_FALLBACK_DONE 2
117 #define MPTCP_WORK_CLOSE_SUBFLOW 3
118
119 /* MPTCP socket release cb flags */
120 #define MPTCP_PUSH_PENDING 1
121 #define MPTCP_CLEAN_UNA 2
122 #define MPTCP_ERROR_REPORT 3
123 #define MPTCP_RETRANSMIT 4
124 #define MPTCP_FLUSH_JOIN_LIST 5
125 #define MPTCP_SYNC_STATE 6
126 #define MPTCP_SYNC_SNDBUF 7
127
128 struct mptcp_skb_cb {
129 u64 map_seq;
130 u64 end_seq;
131 u32 offset;
132 u8 has_rxtstamp;
133 u8 cant_coalesce;
134 };
135
136 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0]))
137
before64(__u64 seq1,__u64 seq2)138 static inline bool before64(__u64 seq1, __u64 seq2)
139 {
140 return (__s64)(seq1 - seq2) < 0;
141 }
142
143 #define after64(seq2, seq1) before64(seq1, seq2)
144
145 struct mptcp_options_received {
146 u64 sndr_key;
147 u64 rcvr_key;
148 u64 data_ack;
149 u64 data_seq;
150 u32 subflow_seq;
151 u16 data_len;
152 __sum16 csum;
153 struct_group(status,
154 u16 suboptions;
155 u16 use_map:1,
156 dsn64:1,
157 data_fin:1,
158 use_ack:1,
159 ack64:1,
160 mpc_map:1,
161 reset_reason:4,
162 reset_transient:1,
163 echo:1,
164 backup:1,
165 deny_join_id0:1,
166 __unused:2;
167 );
168 u8 join_id;
169 u32 token;
170 u32 nonce;
171 u64 thmac;
172 u8 hmac[MPTCPOPT_HMAC_LEN];
173 struct mptcp_addr_info addr;
174 struct mptcp_rm_list rm_list;
175 u64 ahmac;
176 u64 fail_seq;
177 };
178
mptcp_option(u8 subopt,u8 len,u8 nib,u8 field)179 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field)
180 {
181 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) |
182 ((nib & 0xF) << 8) | field);
183 }
184
185 enum mptcp_pm_status {
186 MPTCP_PM_ADD_ADDR_RECEIVED,
187 MPTCP_PM_ADD_ADDR_SEND_ACK,
188 MPTCP_PM_RM_ADDR_RECEIVED,
189 MPTCP_PM_ESTABLISHED,
190 MPTCP_PM_SUBFLOW_ESTABLISHED,
191 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */
192 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is
193 * accounted int id_avail_bitmap
194 */
195 };
196
197 enum mptcp_pm_type {
198 MPTCP_PM_TYPE_KERNEL = 0,
199 MPTCP_PM_TYPE_USERSPACE,
200
201 __MPTCP_PM_TYPE_NR,
202 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1,
203 };
204
205 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */
206 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1)
207
208 enum mptcp_addr_signal_status {
209 MPTCP_ADD_ADDR_SIGNAL,
210 MPTCP_ADD_ADDR_ECHO,
211 MPTCP_RM_ADDR_SIGNAL,
212 };
213
214 /* max value of mptcp_addr_info.id */
215 #define MPTCP_PM_MAX_ADDR_ID U8_MAX
216
217 struct mptcp_pm_data {
218 struct mptcp_addr_info local;
219 struct mptcp_addr_info remote;
220 struct list_head anno_list;
221 struct list_head userspace_pm_local_addr_list;
222
223 spinlock_t lock; /*protects the whole PM data */
224
225 struct_group(reset,
226
227 u8 addr_signal;
228 bool server_side;
229 bool work_pending;
230 bool accept_addr;
231 bool accept_subflow;
232 bool remote_deny_join_id0;
233 u8 add_addr_signaled;
234 u8 add_addr_accepted;
235 u8 local_addr_used;
236 u8 pm_type;
237 u8 extra_subflows;
238 u8 status;
239
240 );
241
242 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
243 struct mptcp_rm_list rm_list_tx;
244 struct mptcp_rm_list rm_list_rx;
245 };
246
247 struct mptcp_pm_local {
248 struct mptcp_addr_info addr;
249 u8 flags;
250 int ifindex;
251 };
252
253 struct mptcp_pm_addr_entry {
254 struct list_head list;
255 struct mptcp_addr_info addr;
256 u8 flags;
257 int ifindex;
258 struct socket *lsk;
259 };
260
261 struct mptcp_data_frag {
262 struct list_head list;
263 u64 data_seq;
264 u16 data_len;
265 u16 offset;
266 u16 overhead;
267 u16 already_sent;
268 struct page *page;
269 };
270
271 /* MPTCP connection sock */
272 struct mptcp_sock {
273 /* inet_connection_sock must be the first member */
274 struct inet_connection_sock sk;
275 u64 local_key; /* protected by the first subflow socket lock
276 * lockless access read
277 */
278 u64 remote_key; /* same as above */
279 u64 write_seq;
280 u64 bytes_sent;
281 u64 snd_nxt;
282 u64 bytes_received;
283 u64 ack_seq;
284 atomic64_t rcv_wnd_sent;
285 u64 rcv_data_fin_seq;
286 u64 bytes_retrans;
287 u64 bytes_consumed;
288 int snd_burst;
289 int old_wspace;
290 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq;
291 * recovery related fields are under data_lock
292 * protection
293 */
294 u64 bytes_acked;
295 u64 snd_una;
296 u64 wnd_end;
297 u32 last_data_sent;
298 u32 last_data_recv;
299 u32 last_ack_recv;
300 unsigned long timer_ival;
301 u32 token;
302 unsigned long flags;
303 unsigned long cb_flags;
304 bool recovery; /* closing subflow write queue reinjected */
305 bool can_ack;
306 bool fully_established;
307 bool rcv_data_fin;
308 bool snd_data_fin_enable;
309 bool rcv_fastclose;
310 bool use_64bit_ack; /* Set when we received a 64-bit DSN */
311 bool csum_enabled;
312 bool allow_infinite_fallback;
313 u8 pending_state; /* A subflow asked to set this sk_state,
314 * protected by the msk data lock
315 */
316 u8 mpc_endpoint_id;
317 u8 recvmsg_inq:1,
318 cork:1,
319 nodelay:1,
320 fastopening:1,
321 in_accept_queue:1,
322 free_first:1,
323 rcvspace_init:1,
324 fastclosing:1;
325 u32 notsent_lowat;
326 int keepalive_cnt;
327 int keepalive_idle;
328 int keepalive_intvl;
329 int maxseg;
330 struct work_struct work;
331 struct sk_buff *ooo_last_skb;
332 struct rb_root out_of_order_queue;
333 struct list_head conn_list;
334 struct list_head rtx_queue;
335 struct mptcp_data_frag *first_pending;
336 struct list_head join_list;
337 struct sock *first; /* The mptcp ops can safely dereference, using suitable
338 * ONCE annotation, the subflow outside the socket
339 * lock as such sock is freed after close().
340 */
341 struct mptcp_pm_data pm;
342 struct mptcp_sched_ops *sched;
343 struct {
344 int space; /* bytes copied in last measurement window */
345 int copied; /* bytes copied in this measurement window */
346 u64 time; /* start time of measurement window */
347 u64 rtt_us; /* last maximum rtt of subflows */
348 } rcvq_space;
349 u8 scaling_ratio;
350 bool allow_subflows;
351
352 u32 subflow_id;
353 u32 setsockopt_seq;
354 char ca_name[TCP_CA_NAME_MAX];
355
356 spinlock_t fallback_lock; /* protects fallback,
357 * allow_infinite_fallback and
358 * allow_join
359 */
360
361 struct list_head backlog_list; /* protected by the data lock */
362 u32 backlog_len;
363 u32 backlog_unaccounted;
364 };
365
366 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock)
367 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock)
368
369 #define mptcp_for_each_subflow(__msk, __subflow) \
370 list_for_each_entry(__subflow, &((__msk)->conn_list), node)
371 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \
372 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node)
373 #define mptcp_next_subflow(__msk, __subflow) \
374 list_next_entry_circular(__subflow, &((__msk)->conn_list), node)
375
376 extern struct genl_family mptcp_genl_family;
377
msk_owned_by_me(const struct mptcp_sock * msk)378 static inline void msk_owned_by_me(const struct mptcp_sock *msk)
379 {
380 sock_owned_by_me((const struct sock *)msk);
381 }
382
383 #ifdef CONFIG_DEBUG_NET
384 /* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */
385 #undef tcp_sk
386 #define tcp_sk(ptr) ({ \
387 typeof(ptr) _ptr = (ptr); \
388 WARN_ON(_ptr->sk_protocol != IPPROTO_TCP); \
389 container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk); \
390 })
391 #define mptcp_sk(ptr) ({ \
392 typeof(ptr) _ptr = (ptr); \
393 WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP); \
394 container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk); \
395 })
396
397 #else /* !CONFIG_DEBUG_NET */
398 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk)
399 #endif
400
mptcp_win_from_space(const struct sock * sk,int space)401 static inline int mptcp_win_from_space(const struct sock *sk, int space)
402 {
403 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space);
404 }
405
mptcp_space_from_win(const struct sock * sk,int win)406 static inline int mptcp_space_from_win(const struct sock *sk, int win)
407 {
408 return __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, win);
409 }
410
__mptcp_space(const struct sock * sk)411 static inline int __mptcp_space(const struct sock *sk)
412 {
413 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) -
414 READ_ONCE(mptcp_sk(sk)->backlog_len) -
415 sk_rmem_alloc_get(sk));
416 }
417
mptcp_send_head(const struct sock * sk)418 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk)
419 {
420 const struct mptcp_sock *msk = mptcp_sk(sk);
421
422 return msk->first_pending;
423 }
424
mptcp_send_next(struct sock * sk)425 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk)
426 {
427 struct mptcp_sock *msk = mptcp_sk(sk);
428 struct mptcp_data_frag *cur;
429
430 cur = msk->first_pending;
431 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL :
432 list_next_entry(cur, list);
433 }
434
mptcp_pending_tail(const struct sock * sk)435 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
436 {
437 const struct mptcp_sock *msk = mptcp_sk(sk);
438
439 if (!msk->first_pending)
440 return NULL;
441
442 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue)))
443 return NULL;
444
445 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
446 }
447
mptcp_rtx_head(struct sock * sk)448 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk)
449 {
450 struct mptcp_sock *msk = mptcp_sk(sk);
451
452 if (msk->snd_una == msk->snd_nxt)
453 return NULL;
454
455 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list);
456 }
457
458 struct csum_pseudo_header {
459 __be64 data_seq;
460 __be32 subflow_seq;
461 __be16 data_len;
462 __sum16 csum;
463 };
464
465 struct mptcp_subflow_request_sock {
466 struct tcp_request_sock sk;
467 u16 mp_capable : 1,
468 mp_join : 1,
469 backup : 1,
470 request_bkup : 1,
471 csum_reqd : 1,
472 allow_join_id0 : 1;
473 u8 local_id;
474 u8 remote_id;
475 u64 local_key;
476 u64 idsn;
477 u32 token;
478 u32 ssn_offset;
479 u64 thmac;
480 u32 local_nonce;
481 u32 remote_nonce;
482 struct mptcp_sock *msk;
483 struct hlist_nulls_node token_node;
484 };
485
486 static inline struct mptcp_subflow_request_sock *
mptcp_subflow_rsk(const struct request_sock * rsk)487 mptcp_subflow_rsk(const struct request_sock *rsk)
488 {
489 return (struct mptcp_subflow_request_sock *)rsk;
490 }
491
492 struct mptcp_delegated_action {
493 struct napi_struct napi;
494 local_lock_t bh_lock;
495 struct list_head head;
496 };
497
498 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
499
500 #define MPTCP_DELEGATE_SCHEDULED 0
501 #define MPTCP_DELEGATE_SEND 1
502 #define MPTCP_DELEGATE_ACK 2
503 #define MPTCP_DELEGATE_SNDBUF 3
504
505 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED))
506 /* MPTCP subflow context */
507 struct mptcp_subflow_context {
508 struct list_head node;/* conn_list of subflows */
509
510 struct_group(reset,
511
512 unsigned long avg_pacing_rate; /* protected by msk socket lock */
513 u64 local_key;
514 u64 remote_key;
515 u64 idsn;
516 u64 map_seq;
517 u64 rcv_wnd_sent;
518 u32 snd_isn;
519 u32 token;
520 u32 rel_write_seq;
521 u32 map_subflow_seq;
522 u32 ssn_offset;
523 u32 map_data_len;
524 __wsum map_data_csum;
525 u32 map_csum_len;
526 u32 request_mptcp : 1, /* send MP_CAPABLE */
527 request_join : 1, /* send MP_JOIN */
528 request_bkup : 1,
529 mp_capable : 1, /* remote is MPTCP capable */
530 mp_join : 1, /* remote is JOINing */
531 pm_notified : 1, /* PM hook called for established status */
532 conn_finished : 1,
533 map_valid : 1,
534 map_csum_reqd : 1,
535 map_data_fin : 1,
536 mpc_map : 1,
537 backup : 1,
538 send_mp_prio : 1,
539 send_mp_fail : 1,
540 send_fastclose : 1,
541 send_infinite_map : 1,
542 remote_key_valid : 1, /* received the peer key from */
543 disposable : 1, /* ctx can be free at ulp release time */
544 closing : 1, /* must not pass rx data to msk anymore */
545 stale : 1, /* unable to snd/rcv data, do not use for xmit */
546 valid_csum_seen : 1, /* at least one csum validated */
547 is_mptfo : 1, /* subflow is doing TFO */
548 close_event_done : 1, /* has done the post-closed part */
549 mpc_drop : 1, /* the MPC option has been dropped in a rtx */
550 __unused : 8;
551 bool data_avail;
552 bool scheduled;
553 bool pm_listener; /* a listener managed by the kernel PM? */
554 bool fully_established; /* path validated */
555 u32 lent_mem_frag;
556 u32 remote_nonce;
557 u64 thmac;
558 u32 local_nonce;
559 u32 remote_token;
560 union {
561 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */
562 u64 iasn; /* initial ack sequence number, MPC subflows only */
563 };
564 s16 local_id; /* if negative not initialized yet */
565 u8 remote_id;
566 u8 reset_seen:1;
567 u8 reset_transient:1;
568 u8 reset_reason:4;
569 u8 stale_count;
570
571 u32 subflow_id;
572
573 long delegated_status;
574 unsigned long fail_tout;
575
576 );
577
578 struct list_head delegated_node; /* link into delegated_action, protected by local BH */
579
580 u32 setsockopt_seq;
581 u32 stale_rcv_tstamp;
582 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf,
583 * protected by the msk socket lock
584 */
585
586 struct sock *tcp_sock; /* tcp sk backpointer */
587 struct sock *conn; /* parent mptcp_sock */
588 const struct inet_connection_sock_af_ops *icsk_af_ops;
589 void (*tcp_state_change)(struct sock *sk);
590 void (*tcp_error_report)(struct sock *sk);
591
592 struct rcu_head rcu;
593 };
594
595 static inline struct mptcp_subflow_context *
mptcp_subflow_ctx(const struct sock * sk)596 mptcp_subflow_ctx(const struct sock *sk)
597 {
598 const struct inet_connection_sock *icsk = inet_csk(sk);
599
600 /* Use RCU on icsk_ulp_data only for sock diag code */
601 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data;
602 }
603
604 static inline struct sock *
mptcp_subflow_tcp_sock(const struct mptcp_subflow_context * subflow)605 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
606 {
607 return subflow->tcp_sock;
608 }
609
610 static inline void
mptcp_subflow_ctx_reset(struct mptcp_subflow_context * subflow)611 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow)
612 {
613 memset(&subflow->reset, 0, sizeof(subflow->reset));
614 subflow->request_mptcp = 1;
615 WRITE_ONCE(subflow->local_id, -1);
616 }
617
618 /* Convert reset reasons in MPTCP to enum sk_rst_reason type */
619 static inline enum sk_rst_reason
sk_rst_convert_mptcp_reason(u32 reason)620 sk_rst_convert_mptcp_reason(u32 reason)
621 {
622 switch (reason) {
623 case MPTCP_RST_EUNSPEC:
624 return SK_RST_REASON_MPTCP_RST_EUNSPEC;
625 case MPTCP_RST_EMPTCP:
626 return SK_RST_REASON_MPTCP_RST_EMPTCP;
627 case MPTCP_RST_ERESOURCE:
628 return SK_RST_REASON_MPTCP_RST_ERESOURCE;
629 case MPTCP_RST_EPROHIBIT:
630 return SK_RST_REASON_MPTCP_RST_EPROHIBIT;
631 case MPTCP_RST_EWQ2BIG:
632 return SK_RST_REASON_MPTCP_RST_EWQ2BIG;
633 case MPTCP_RST_EBADPERF:
634 return SK_RST_REASON_MPTCP_RST_EBADPERF;
635 case MPTCP_RST_EMIDDLEBOX:
636 return SK_RST_REASON_MPTCP_RST_EMIDDLEBOX;
637 default:
638 /* It should not happen, or else errors may occur
639 * in MPTCP layer
640 */
641 return SK_RST_REASON_ERROR;
642 }
643 }
644
645 static inline void
mptcp_send_active_reset_reason(struct sock * sk)646 mptcp_send_active_reset_reason(struct sock *sk)
647 {
648 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
649 enum sk_rst_reason reason;
650
651 reason = sk_rst_convert_mptcp_reason(subflow->reset_reason);
652 tcp_send_active_reset(sk, GFP_ATOMIC, reason);
653 }
654
655 /* Made the fwd mem carried by the given skb available to the msk,
656 * To be paired with a previous mptcp_subflow_lend_fwdmem() before freeing
657 * the skb or setting the skb ownership.
658 */
mptcp_borrow_fwdmem(struct sock * sk,struct sk_buff * skb)659 static inline void mptcp_borrow_fwdmem(struct sock *sk, struct sk_buff *skb)
660 {
661 struct sock *ssk = skb->sk;
662
663 /* The subflow just lend the skb fwd memory; if the subflow meanwhile
664 * closed, mptcp_close_ssk() already released the ssk rcv memory.
665 */
666 DEBUG_NET_WARN_ON_ONCE(skb->destructor);
667 sk_forward_alloc_add(sk, skb->truesize);
668 if (!ssk)
669 return;
670
671 atomic_sub(skb->truesize, &ssk->sk_rmem_alloc);
672 skb->sk = NULL;
673 }
674
675 static inline void
__mptcp_subflow_lend_fwdmem(struct mptcp_subflow_context * subflow,int size)676 __mptcp_subflow_lend_fwdmem(struct mptcp_subflow_context *subflow, int size)
677 {
678 int frag = (subflow->lent_mem_frag + size) & (PAGE_SIZE - 1);
679
680 subflow->lent_mem_frag = frag;
681 }
682
683 static inline void
mptcp_subflow_lend_fwdmem(struct mptcp_subflow_context * subflow,struct sk_buff * skb)684 mptcp_subflow_lend_fwdmem(struct mptcp_subflow_context *subflow,
685 struct sk_buff *skb)
686 {
687 __mptcp_subflow_lend_fwdmem(subflow, skb->truesize);
688 skb->destructor = NULL;
689 }
690
691 static inline u64
mptcp_subflow_get_map_offset(const struct mptcp_subflow_context * subflow)692 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow)
693 {
694 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq -
695 subflow->ssn_offset -
696 subflow->map_subflow_seq;
697 }
698
699 static inline u64
mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context * subflow)700 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow)
701 {
702 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow);
703 }
704
705 void mptcp_subflow_process_delegated(struct sock *ssk, long actions);
706
mptcp_subflow_delegate(struct mptcp_subflow_context * subflow,int action)707 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action)
708 {
709 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action);
710 struct mptcp_delegated_action *delegated;
711 bool schedule;
712
713 /* the caller held the subflow bh socket lock */
714 lockdep_assert_in_softirq();
715
716 /* The implied barrier pairs with tcp_release_cb_override()
717 * mptcp_napi_poll(), and ensures the below list check sees list
718 * updates done prior to delegated status bits changes
719 */
720 old = set_mask_bits(&subflow->delegated_status, 0, set_bits);
721 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) {
722 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node)))
723 return;
724
725 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock);
726 delegated = this_cpu_ptr(&mptcp_delegated_actions);
727 schedule = list_empty(&delegated->head);
728 list_add_tail(&subflow->delegated_node, &delegated->head);
729 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock);
730 sock_hold(mptcp_subflow_tcp_sock(subflow));
731 if (schedule)
732 napi_schedule(&delegated->napi);
733 }
734 }
735
736 static inline struct mptcp_subflow_context *
mptcp_subflow_delegated_next(struct mptcp_delegated_action * delegated)737 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated)
738 {
739 struct mptcp_subflow_context *ret;
740
741 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock);
742 if (list_empty(&delegated->head)) {
743 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock);
744 return NULL;
745 }
746
747 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node);
748 list_del_init(&ret->delegated_node);
749 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock);
750 return ret;
751 }
752
753 void __mptcp_inherit_memcg(struct sock *sk, struct sock *ssk, gfp_t gfp);
754 void __mptcp_inherit_cgrp_data(struct sock *sk, struct sock *ssk);
755
756 int mptcp_is_enabled(const struct net *net);
757 unsigned int mptcp_get_add_addr_timeout(const struct net *net);
758 int mptcp_is_checksum_enabled(const struct net *net);
759 int mptcp_allow_join_id0(const struct net *net);
760 unsigned int mptcp_stale_loss_cnt(const struct net *net);
761 unsigned int mptcp_close_timeout(const struct sock *sk);
762 int mptcp_get_pm_type(const struct net *net);
763 const char *mptcp_get_path_manager(const struct net *net);
764 const char *mptcp_get_scheduler(const struct net *net);
765
766 void mptcp_active_disable(struct sock *sk);
767 bool mptcp_active_should_disable(struct sock *ssk);
768 void mptcp_active_enable(struct sock *sk);
769
770 void mptcp_get_available_schedulers(char *buf, size_t maxlen);
771 void __mptcp_subflow_fully_established(struct mptcp_sock *msk,
772 struct mptcp_subflow_context *subflow,
773 const struct mptcp_options_received *mp_opt);
774 bool __mptcp_retransmit_pending_data(struct sock *sk);
775 void mptcp_check_and_set_pending(struct sock *sk);
776 void __mptcp_push_pending(struct sock *sk, unsigned int flags);
777 bool mptcp_subflow_data_available(struct sock *sk);
778 void __init mptcp_subflow_init(void);
779 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how);
780 void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
781 struct mptcp_subflow_context *subflow);
782 void __mptcp_subflow_send_ack(struct sock *ssk);
783 void mptcp_subflow_reset(struct sock *ssk);
784 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk);
785 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
786 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk);
787 bool __mptcp_close(struct sock *sk, long timeout);
788 void mptcp_cancel_work(struct sock *sk);
789 void __mptcp_unaccepted_force_close(struct sock *sk);
790 void mptcp_set_state(struct sock *sk, int state);
791
792 bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
793 const struct mptcp_addr_info *b, bool use_port);
794 void mptcp_local_address(const struct sock_common *skc,
795 struct mptcp_addr_info *addr);
796 void mptcp_remote_address(const struct sock_common *skc,
797 struct mptcp_addr_info *addr);
798
799 /* called with sk socket lock held */
800 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_pm_local *local,
801 const struct mptcp_addr_info *remote);
802 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family,
803 struct socket **new_sock);
804 void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
805 struct sockaddr_storage *addr,
806 unsigned short family);
807 struct mptcp_sched_ops *mptcp_sched_find(const char *name);
808 int mptcp_validate_scheduler(struct mptcp_sched_ops *sched);
809 int mptcp_register_scheduler(struct mptcp_sched_ops *sched);
810 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched);
811 void mptcp_sched_init(void);
812 int mptcp_init_sched(struct mptcp_sock *msk,
813 struct mptcp_sched_ops *sched);
814 void mptcp_release_sched(struct mptcp_sock *msk);
815 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
816 bool scheduled);
817 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk);
818 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk);
819 int mptcp_sched_get_send(struct mptcp_sock *msk);
820 int mptcp_sched_get_retrans(struct mptcp_sock *msk);
821
mptcp_data_avail(const struct mptcp_sock * msk)822 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk)
823 {
824 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed);
825 }
826
mptcp_epollin_ready(const struct sock * sk)827 static inline bool mptcp_epollin_ready(const struct sock *sk)
828 {
829 u64 data_avail = mptcp_data_avail(mptcp_sk(sk));
830
831 if (!data_avail)
832 return false;
833
834 /* mptcp doesn't have to deal with small skbs in the receive queue,
835 * as it can always coalesce them
836 */
837 return (data_avail >= sk->sk_rcvlowat) ||
838 tcp_under_memory_pressure(sk);
839 }
840
841 int mptcp_set_rcvlowat(struct sock *sk, int val);
842
__tcp_can_send(const struct sock * ssk)843 static inline bool __tcp_can_send(const struct sock *ssk)
844 {
845 /* only send if our side has not closed yet */
846 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT));
847 }
848
__mptcp_subflow_active(struct mptcp_subflow_context * subflow)849 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow)
850 {
851 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */
852 if (subflow->request_join && !READ_ONCE(subflow->fully_established))
853 return false;
854
855 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow));
856 }
857
858 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow);
859
860 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow);
861
862 void mptcp_subflow_drop_ctx(struct sock *ssk);
863
mptcp_subflow_tcp_fallback(struct sock * sk,struct mptcp_subflow_context * ctx)864 static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
865 struct mptcp_subflow_context *ctx)
866 {
867 sk->sk_data_ready = sock_def_readable;
868 sk->sk_state_change = ctx->tcp_state_change;
869 sk->sk_write_space = sk_stream_write_space;
870 sk->sk_error_report = ctx->tcp_error_report;
871
872 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
873 }
874
875 void __init mptcp_proto_init(void);
876 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
877 int __init mptcp_proto_v6_init(void);
878 #endif
879
880 struct sock *mptcp_sk_clone_init(const struct sock *sk,
881 const struct mptcp_options_received *mp_opt,
882 struct sock *ssk,
883 struct request_sock *req);
884 void mptcp_get_options(const struct sk_buff *skb,
885 struct mptcp_options_received *mp_opt);
886
887 void mptcp_finish_connect(struct sock *sk);
888 void __mptcp_sync_state(struct sock *sk, int state);
889 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout);
890
mptcp_stop_tout_timer(struct sock * sk)891 static inline void mptcp_stop_tout_timer(struct sock *sk)
892 {
893 if (!inet_csk(sk)->icsk_mtup.probe_timestamp)
894 return;
895
896 sk_stop_timer(sk, &inet_csk(sk)->mptcp_tout_timer);
897 inet_csk(sk)->icsk_mtup.probe_timestamp = 0;
898 }
899
mptcp_set_close_tout(struct sock * sk,unsigned long tout)900 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout)
901 {
902 /* avoid 0 timestamp, as that means no close timeout */
903 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1;
904 }
905
mptcp_start_tout_timer(struct sock * sk)906 static inline void mptcp_start_tout_timer(struct sock *sk)
907 {
908 mptcp_set_close_tout(sk, tcp_jiffies32);
909 mptcp_reset_tout_timer(mptcp_sk(sk), 0);
910 }
911
mptcp_is_fully_established(struct sock * sk)912 static inline bool mptcp_is_fully_established(struct sock *sk)
913 {
914 return inet_sk_state_load(sk) == TCP_ESTABLISHED &&
915 READ_ONCE(mptcp_sk(sk)->fully_established);
916 }
917
918 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk);
919 void mptcp_data_ready(struct sock *sk, struct sock *ssk);
920 bool mptcp_finish_join(struct sock *sk);
921 bool mptcp_schedule_work(struct sock *sk);
922 int mptcp_setsockopt(struct sock *sk, int level, int optname,
923 sockptr_t optval, unsigned int optlen);
924 int mptcp_getsockopt(struct sock *sk, int level, int optname,
925 char __user *optval, int __user *option);
926
927 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq);
mptcp_expand_seq(u64 old_seq,u64 cur_seq,bool use_64bit)928 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit)
929 {
930 if (use_64bit)
931 return cur_seq;
932
933 return __mptcp_expand_seq(old_seq, cur_seq);
934 }
935 void __mptcp_check_push(struct sock *sk, struct sock *ssk);
936 void __mptcp_data_acked(struct sock *sk);
937 void __mptcp_error_report(struct sock *sk);
938 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit);
mptcp_data_fin_enabled(const struct mptcp_sock * msk)939 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk)
940 {
941 return READ_ONCE(msk->snd_data_fin_enable) &&
942 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt);
943 }
944
mptcp_notsent_lowat(const struct sock * sk)945 static inline u32 mptcp_notsent_lowat(const struct sock *sk)
946 {
947 struct net *net = sock_net(sk);
948 u32 val;
949
950 val = READ_ONCE(mptcp_sk(sk)->notsent_lowat);
951 return val ?: READ_ONCE(net->ipv4.sysctl_tcp_notsent_lowat);
952 }
953
mptcp_stream_memory_free(const struct sock * sk,int wake)954 static inline bool mptcp_stream_memory_free(const struct sock *sk, int wake)
955 {
956 const struct mptcp_sock *msk = mptcp_sk(sk);
957 u32 notsent_bytes;
958
959 notsent_bytes = READ_ONCE(msk->write_seq) - READ_ONCE(msk->snd_nxt);
960 return (notsent_bytes << wake) < mptcp_notsent_lowat(sk);
961 }
962
__mptcp_stream_is_writeable(const struct sock * sk,int wake)963 static inline bool __mptcp_stream_is_writeable(const struct sock *sk, int wake)
964 {
965 return mptcp_stream_memory_free(sk, wake) &&
966 __sk_stream_is_writeable(sk, wake);
967 }
968
mptcp_write_space(struct sock * sk)969 static inline void mptcp_write_space(struct sock *sk)
970 {
971 /* pairs with memory barrier in mptcp_poll */
972 smp_mb();
973 if (mptcp_stream_memory_free(sk, 1))
974 sk_stream_write_space(sk);
975 }
976
__mptcp_sync_sndbuf(struct sock * sk)977 static inline void __mptcp_sync_sndbuf(struct sock *sk)
978 {
979 struct mptcp_subflow_context *subflow;
980 int ssk_sndbuf, new_sndbuf;
981
982 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
983 return;
984
985 new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]);
986 mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
987 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf);
988
989 subflow->cached_sndbuf = ssk_sndbuf;
990 new_sndbuf += ssk_sndbuf;
991 }
992
993 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */
994 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf);
995 mptcp_write_space(sk);
996 }
997
998 /* The called held both the msk socket and the subflow socket locks,
999 * possibly under BH
1000 */
__mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)1001 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
1002 {
1003 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1004
1005 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf)
1006 __mptcp_sync_sndbuf(sk);
1007 }
1008
1009 /* the caller held only the subflow socket lock, either in process or
1010 * BH context. Additionally this can be called under the msk data lock,
1011 * so we can't acquire such lock here: let the delegate action acquires
1012 * the needed locks in suitable order.
1013 */
mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)1014 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
1015 {
1016 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1017
1018 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf))
1019 return;
1020
1021 local_bh_disable();
1022 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF);
1023 local_bh_enable();
1024 }
1025
1026 #define MPTCP_TOKEN_MAX_RETRIES 4
1027
1028 void __init mptcp_token_init(void);
mptcp_token_init_request(struct request_sock * req)1029 static inline void mptcp_token_init_request(struct request_sock *req)
1030 {
1031 mptcp_subflow_rsk(req)->token_node.pprev = NULL;
1032 }
1033
1034 int mptcp_token_new_request(struct request_sock *req);
1035 void mptcp_token_destroy_request(struct request_sock *req);
1036 int mptcp_token_new_connect(struct sock *ssk);
1037 void mptcp_token_accept(struct mptcp_subflow_request_sock *r,
1038 struct mptcp_sock *msk);
1039 bool mptcp_token_exists(u32 token);
1040 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token);
1041 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot,
1042 long *s_num);
1043 void mptcp_token_destroy(struct mptcp_sock *msk);
1044
1045 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
1046
1047 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac);
1048 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum);
1049
1050 void __init mptcp_pm_init(void);
1051 void mptcp_pm_data_init(struct mptcp_sock *msk);
1052 void mptcp_pm_data_reset(struct mptcp_sock *msk);
1053 void mptcp_pm_destroy(struct mptcp_sock *msk);
1054 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
1055 struct mptcp_addr_info *addr);
1056 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
1057 bool require_family,
1058 struct mptcp_pm_addr_entry *entry);
1059 bool mptcp_pm_addr_families_match(const struct sock *sk,
1060 const struct mptcp_addr_info *loc,
1061 const struct mptcp_addr_info *rem);
1062 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
1063 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side);
1064 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk);
1065 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk);
1066 void mptcp_pm_connection_closed(struct mptcp_sock *msk);
1067 void mptcp_pm_subflow_established(struct mptcp_sock *msk);
1068 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk);
1069 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk,
1070 const struct mptcp_subflow_context *subflow);
1071 void mptcp_pm_add_addr_received(const struct sock *ssk,
1072 const struct mptcp_addr_info *addr);
1073 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
1074 const struct mptcp_addr_info *addr);
1075 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk);
1076 void mptcp_pm_send_ack(struct mptcp_sock *msk,
1077 struct mptcp_subflow_context *subflow,
1078 bool prio, bool backup);
1079 void mptcp_pm_addr_send_ack(struct mptcp_sock *msk);
1080 void mptcp_pm_nl_rm_addr(struct mptcp_sock *msk, u8 rm_id);
1081 void mptcp_pm_rm_subflow(struct mptcp_sock *msk,
1082 const struct mptcp_rm_list *rm_list);
1083 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
1084 const struct mptcp_rm_list *rm_list);
1085 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
1086 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
1087 int mptcp_pm_mp_prio_send_ack(struct mptcp_sock *msk,
1088 struct mptcp_addr_info *addr,
1089 struct mptcp_addr_info *rem,
1090 u8 bkup);
1091 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
1092 const struct mptcp_addr_info *addr);
1093 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
1094 struct mptcp_pm_add_entry *
1095 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
1096 const struct mptcp_addr_info *addr, bool check_id);
1097 bool mptcp_lookup_subflow_by_saddr(const struct list_head *list,
1098 const struct mptcp_addr_info *saddr);
1099 bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk,
1100 const struct mptcp_addr_info *addr);
1101 int mptcp_pm_nl_set_flags(struct mptcp_pm_addr_entry *local,
1102 struct genl_info *info);
1103 int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local,
1104 struct genl_info *info);
1105 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
1106 const struct mptcp_addr_info *addr,
1107 bool echo);
1108 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
1109 void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
1110 struct mptcp_pm_addr_entry *entry);
1111
1112 /* the default path manager, used in mptcp_pm_unregister */
1113 extern struct mptcp_pm_ops mptcp_pm_kernel;
1114
1115 struct mptcp_pm_ops *mptcp_pm_find(const char *name);
1116 int mptcp_pm_register(struct mptcp_pm_ops *pm_ops);
1117 void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops);
1118 int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops);
1119 void mptcp_pm_get_available(char *buf, size_t maxlen);
1120
1121 void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk);
1122
1123 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
1124 const struct sock *ssk, gfp_t gfp);
1125 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info);
1126 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
1127 void mptcp_event_pm_listener(const struct sock *ssk,
1128 enum mptcp_event_type event);
1129 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk);
1130
1131 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow,
1132 struct request_sock *req);
1133 int mptcp_pm_genl_fill_addr(struct sk_buff *msg,
1134 struct netlink_callback *cb,
1135 struct mptcp_pm_addr_entry *entry);
1136
mptcp_pm_should_add_signal(struct mptcp_sock * msk)1137 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk)
1138 {
1139 return READ_ONCE(msk->pm.addr_signal) &
1140 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
1141 }
1142
mptcp_pm_should_add_signal_addr(struct mptcp_sock * msk)1143 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk)
1144 {
1145 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL);
1146 }
1147
mptcp_pm_should_add_signal_echo(struct mptcp_sock * msk)1148 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk)
1149 {
1150 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO);
1151 }
1152
mptcp_pm_should_rm_signal(struct mptcp_sock * msk)1153 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)
1154 {
1155 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL);
1156 }
1157
mptcp_pm_is_userspace(const struct mptcp_sock * msk)1158 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk)
1159 {
1160 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE;
1161 }
1162
mptcp_pm_is_kernel(const struct mptcp_sock * msk)1163 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk)
1164 {
1165 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL;
1166 }
1167
mptcp_add_addr_len(int family,bool echo,bool port)1168 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port)
1169 {
1170 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
1171
1172 if (family == AF_INET6)
1173 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
1174 if (!echo)
1175 len += MPTCPOPT_THMAC_LEN;
1176 /* account for 2 trailing 'nop' options */
1177 if (port)
1178 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
1179
1180 return len;
1181 }
1182
mptcp_rm_addr_len(const struct mptcp_rm_list * rm_list)1183 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
1184 {
1185 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX)
1186 return -EINVAL;
1187
1188 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
1189 }
1190
1191 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
1192 unsigned int opt_size, unsigned int remaining,
1193 struct mptcp_addr_info *addr, bool *echo,
1194 bool *drop_other_suboptions);
1195 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
1196 struct mptcp_rm_list *rm_list);
1197 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
1198 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk,
1199 struct mptcp_pm_addr_entry *skc);
1200 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk,
1201 struct mptcp_pm_addr_entry *skc);
1202 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc);
1203 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1204 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1205 int mptcp_pm_nl_dump_addr(struct sk_buff *msg,
1206 struct netlink_callback *cb);
1207 int mptcp_userspace_pm_dump_addr(struct sk_buff *msg,
1208 struct netlink_callback *cb);
1209 int mptcp_pm_nl_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
1210 struct genl_info *info);
1211 int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
1212 struct genl_info *info);
1213
subflow_get_local_id(const struct mptcp_subflow_context * subflow)1214 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow)
1215 {
1216 int local_id = READ_ONCE(subflow->local_id);
1217
1218 if (local_id < 0)
1219 return 0;
1220 return local_id;
1221 }
1222
1223 void __init mptcp_pm_kernel_register(void);
1224 void __init mptcp_pm_userspace_register(void);
1225 void __init mptcp_pm_nl_init(void);
1226 void mptcp_pm_worker(struct mptcp_sock *msk);
1227 void __mptcp_pm_kernel_worker(struct mptcp_sock *msk);
1228 u8 mptcp_pm_get_endp_signal_max(const struct mptcp_sock *msk);
1229 u8 mptcp_pm_get_endp_subflow_max(const struct mptcp_sock *msk);
1230 u8 mptcp_pm_get_endp_laminar_max(const struct mptcp_sock *msk);
1231 u8 mptcp_pm_get_endp_fullmesh_max(const struct mptcp_sock *msk);
1232 u8 mptcp_pm_get_limit_add_addr_accepted(const struct mptcp_sock *msk);
1233 u8 mptcp_pm_get_limit_extra_subflows(const struct mptcp_sock *msk);
1234
1235 /* called under PM lock */
__mptcp_pm_close_subflow(struct mptcp_sock * msk)1236 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk)
1237 {
1238 if (--msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk))
1239 WRITE_ONCE(msk->pm.accept_subflow, true);
1240 }
1241
mptcp_pm_close_subflow(struct mptcp_sock * msk)1242 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk)
1243 {
1244 spin_lock_bh(&msk->pm.lock);
1245 __mptcp_pm_close_subflow(msk);
1246 spin_unlock_bh(&msk->pm.lock);
1247 }
1248
mptcp_pm_add_addr_c_flag_case(struct mptcp_sock * msk)1249 static inline bool mptcp_pm_add_addr_c_flag_case(struct mptcp_sock *msk)
1250 {
1251 return READ_ONCE(msk->pm.remote_deny_join_id0) &&
1252 msk->pm.local_addr_used == 0 &&
1253 mptcp_pm_get_limit_add_addr_accepted(msk) == 0 &&
1254 msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk);
1255 }
1256
1257 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk);
1258
mptcp_get_ext(const struct sk_buff * skb)1259 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb)
1260 {
1261 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
1262 }
1263
1264 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);
1265
__mptcp_check_fallback(const struct mptcp_sock * msk)1266 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)
1267 {
1268 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags);
1269 }
1270
mptcp_check_fallback(const struct sock * sk)1271 static inline bool mptcp_check_fallback(const struct sock *sk)
1272 {
1273 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1274 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
1275
1276 return __mptcp_check_fallback(msk);
1277 }
1278
__mptcp_has_initial_subflow(const struct mptcp_sock * msk)1279 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk)
1280 {
1281 struct sock *ssk = READ_ONCE(msk->first);
1282
1283 return ssk && ((1 << inet_sk_state_load(ssk)) &
1284 (TCPF_ESTABLISHED | TCPF_SYN_SENT |
1285 TCPF_SYN_RECV | TCPF_LISTEN));
1286 }
1287
1288 bool __mptcp_try_fallback(struct mptcp_sock *msk, int fb_mib);
1289
mptcp_try_fallback(struct sock * ssk,int fb_mib)1290 static inline bool mptcp_try_fallback(struct sock *ssk, int fb_mib)
1291 {
1292 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1293 struct sock *sk = subflow->conn;
1294 struct mptcp_sock *msk;
1295
1296 msk = mptcp_sk(sk);
1297 if (!__mptcp_try_fallback(msk, fb_mib))
1298 return false;
1299 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) {
1300 gfp_t saved_allocation = ssk->sk_allocation;
1301
1302 /* we are in a atomic (BH) scope, override ssk default for data
1303 * fin allocation
1304 */
1305 ssk->sk_allocation = GFP_ATOMIC;
1306 ssk->sk_shutdown |= SEND_SHUTDOWN;
1307 tcp_shutdown(ssk, SEND_SHUTDOWN);
1308 ssk->sk_allocation = saved_allocation;
1309 }
1310 return true;
1311 }
1312
mptcp_early_fallback(struct mptcp_sock * msk,struct mptcp_subflow_context * subflow,int fb_mib)1313 static inline void mptcp_early_fallback(struct mptcp_sock *msk,
1314 struct mptcp_subflow_context *subflow,
1315 int fb_mib)
1316 {
1317 subflow->request_mptcp = 0;
1318 WARN_ON_ONCE(!__mptcp_try_fallback(msk, fb_mib));
1319 }
1320
mptcp_check_infinite_map(struct sk_buff * skb)1321 static inline bool mptcp_check_infinite_map(struct sk_buff *skb)
1322 {
1323 struct mptcp_ext *mpext;
1324
1325 mpext = skb ? mptcp_get_ext(skb) : NULL;
1326 if (mpext && mpext->infinite_map)
1327 return true;
1328
1329 return false;
1330 }
1331
is_active_ssk(struct mptcp_subflow_context * subflow)1332 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow)
1333 {
1334 return (subflow->request_mptcp || subflow->request_join);
1335 }
1336
subflow_simultaneous_connect(struct sock * sk)1337 static inline bool subflow_simultaneous_connect(struct sock *sk)
1338 {
1339 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1340
1341 /* Note that the sk state implies !subflow->conn_finished. */
1342 return sk->sk_state == TCP_SYN_RECV && is_active_ssk(subflow);
1343 }
1344
1345 #ifdef CONFIG_SYN_COOKIES
1346 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1347 struct sk_buff *skb);
1348 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1349 struct sk_buff *skb);
1350 void __init mptcp_join_cookie_init(void);
1351 #else
1352 static inline void
subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1353 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1354 struct sk_buff *skb) {}
1355 static inline bool
mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1356 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1357 struct sk_buff *skb)
1358 {
1359 return false;
1360 }
1361
mptcp_join_cookie_init(void)1362 static inline void mptcp_join_cookie_init(void) {}
1363 #endif
1364
1365 #endif /* __MPTCP_PROTOCOL_H */
1366