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 #define MPTCP_DEQUEUE 8
128
129 struct mptcp_skb_cb {
130 u64 map_seq;
131 u64 end_seq;
132 u32 offset;
133 u8 has_rxtstamp;
134 u8 cant_coalesce;
135 };
136
137 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0]))
138
before64(__u64 seq1,__u64 seq2)139 static inline bool before64(__u64 seq1, __u64 seq2)
140 {
141 return (__s64)(seq1 - seq2) < 0;
142 }
143
144 #define after64(seq2, seq1) before64(seq1, seq2)
145
146 struct mptcp_options_received {
147 u64 sndr_key;
148 u64 rcvr_key;
149 u64 data_ack;
150 u64 data_seq;
151 u32 subflow_seq;
152 u16 data_len;
153 __sum16 csum;
154 struct_group(status,
155 u16 suboptions;
156 u16 use_map:1,
157 dsn64:1,
158 data_fin:1,
159 use_ack:1,
160 ack64:1,
161 mpc_map:1,
162 reset_reason:4,
163 reset_transient:1,
164 echo:1,
165 backup:1,
166 deny_join_id0:1,
167 __unused:2;
168 );
169 u8 join_id;
170 u32 token;
171 u32 nonce;
172 u64 thmac;
173 u8 hmac[MPTCPOPT_HMAC_LEN];
174 struct mptcp_addr_info addr;
175 struct mptcp_rm_list rm_list;
176 u64 ahmac;
177 u64 fail_seq;
178 };
179
mptcp_option(u8 subopt,u8 len,u8 nib,u8 field)180 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field)
181 {
182 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) |
183 ((nib & 0xF) << 8) | field);
184 }
185
186 enum mptcp_pm_status {
187 MPTCP_PM_ADD_ADDR_RECEIVED,
188 MPTCP_PM_ADD_ADDR_SEND_ACK,
189 MPTCP_PM_RM_ADDR_RECEIVED,
190 MPTCP_PM_ESTABLISHED,
191 MPTCP_PM_SUBFLOW_ESTABLISHED,
192 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */
193 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is
194 * accounted int id_avail_bitmap
195 */
196 };
197
198 enum mptcp_pm_type {
199 MPTCP_PM_TYPE_KERNEL = 0,
200 MPTCP_PM_TYPE_USERSPACE,
201
202 __MPTCP_PM_TYPE_NR,
203 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1,
204 };
205
206 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */
207 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1)
208
209 enum mptcp_addr_signal_status {
210 MPTCP_ADD_ADDR_SIGNAL,
211 MPTCP_ADD_ADDR_ECHO,
212 MPTCP_RM_ADDR_SIGNAL,
213 };
214
215 /* max value of mptcp_addr_info.id */
216 #define MPTCP_PM_MAX_ADDR_ID U8_MAX
217
218 struct mptcp_pm_data {
219 struct mptcp_addr_info local;
220 struct mptcp_addr_info remote;
221 struct list_head anno_list;
222 struct list_head userspace_pm_local_addr_list;
223
224 spinlock_t lock; /*protects the whole PM data */
225
226 struct_group(reset,
227
228 u8 addr_signal;
229 bool server_side;
230 bool work_pending;
231 bool accept_addr;
232 bool accept_subflow;
233 bool remote_deny_join_id0;
234 u8 add_addr_signaled;
235 u8 add_addr_accepted;
236 u8 local_addr_used;
237 u8 pm_type;
238 u8 extra_subflows;
239 u8 status;
240
241 );
242
243 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
244 struct mptcp_rm_list rm_list_tx;
245 struct mptcp_rm_list rm_list_rx;
246 };
247
248 struct mptcp_pm_local {
249 struct mptcp_addr_info addr;
250 u8 flags;
251 int ifindex;
252 };
253
254 struct mptcp_pm_addr_entry {
255 struct list_head list;
256 struct mptcp_addr_info addr;
257 u8 flags;
258 int ifindex;
259 struct socket *lsk;
260 };
261
262 struct mptcp_data_frag {
263 struct list_head list;
264 u64 data_seq;
265 u16 data_len;
266 u16 offset;
267 u16 overhead;
268 u16 already_sent;
269 struct page *page;
270 };
271
272 /* MPTCP connection sock */
273 struct mptcp_sock {
274 /* inet_connection_sock must be the first member */
275 struct inet_connection_sock sk;
276 u64 local_key; /* protected by the first subflow socket lock
277 * lockless access read
278 */
279 u64 remote_key; /* same as above */
280 u64 write_seq;
281 u64 bytes_sent;
282 u64 snd_nxt;
283 u64 bytes_received;
284 u64 ack_seq;
285 atomic64_t rcv_wnd_sent;
286 u64 rcv_data_fin_seq;
287 u64 bytes_retrans;
288 u64 bytes_consumed;
289 int snd_burst;
290 int old_wspace;
291 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq;
292 * recovery related fields are under data_lock
293 * protection
294 */
295 u64 bytes_acked;
296 u64 snd_una;
297 u64 wnd_end;
298 u32 last_data_sent;
299 u32 last_data_recv;
300 u32 last_ack_recv;
301 unsigned long timer_ival;
302 u32 token;
303 unsigned long flags;
304 unsigned long cb_flags;
305 bool recovery; /* closing subflow write queue reinjected */
306 bool can_ack;
307 bool fully_established;
308 bool rcv_data_fin;
309 bool snd_data_fin_enable;
310 bool rcv_fastclose;
311 bool use_64bit_ack; /* Set when we received a 64-bit DSN */
312 bool csum_enabled;
313 bool allow_infinite_fallback;
314 u8 pending_state; /* A subflow asked to set this sk_state,
315 * protected by the msk data lock
316 */
317 u8 mpc_endpoint_id;
318 u8 recvmsg_inq:1,
319 cork:1,
320 nodelay:1,
321 fastopening:1,
322 in_accept_queue:1,
323 free_first:1,
324 rcvspace_init: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
362 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock)
363 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock)
364
365 #define mptcp_for_each_subflow(__msk, __subflow) \
366 list_for_each_entry(__subflow, &((__msk)->conn_list), node)
367 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \
368 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node)
369 #define mptcp_next_subflow(__msk, __subflow) \
370 list_next_entry_circular(__subflow, &((__msk)->conn_list), node)
371
372 extern struct genl_family mptcp_genl_family;
373
msk_owned_by_me(const struct mptcp_sock * msk)374 static inline void msk_owned_by_me(const struct mptcp_sock *msk)
375 {
376 sock_owned_by_me((const struct sock *)msk);
377 }
378
379 #ifdef CONFIG_DEBUG_NET
380 /* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */
381 #undef tcp_sk
382 #define tcp_sk(ptr) ({ \
383 typeof(ptr) _ptr = (ptr); \
384 WARN_ON(_ptr->sk_protocol != IPPROTO_TCP); \
385 container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk); \
386 })
387 #define mptcp_sk(ptr) ({ \
388 typeof(ptr) _ptr = (ptr); \
389 WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP); \
390 container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk); \
391 })
392
393 #else /* !CONFIG_DEBUG_NET */
394 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk)
395 #endif
396
mptcp_win_from_space(const struct sock * sk,int space)397 static inline int mptcp_win_from_space(const struct sock *sk, int space)
398 {
399 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space);
400 }
401
mptcp_space_from_win(const struct sock * sk,int win)402 static inline int mptcp_space_from_win(const struct sock *sk, int win)
403 {
404 return __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, win);
405 }
406
__mptcp_space(const struct sock * sk)407 static inline int __mptcp_space(const struct sock *sk)
408 {
409 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) -
410 sk_rmem_alloc_get(sk));
411 }
412
mptcp_send_head(const struct sock * sk)413 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk)
414 {
415 const struct mptcp_sock *msk = mptcp_sk(sk);
416
417 return msk->first_pending;
418 }
419
mptcp_send_next(struct sock * sk)420 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk)
421 {
422 struct mptcp_sock *msk = mptcp_sk(sk);
423 struct mptcp_data_frag *cur;
424
425 cur = msk->first_pending;
426 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL :
427 list_next_entry(cur, list);
428 }
429
mptcp_pending_tail(const struct sock * sk)430 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
431 {
432 const struct mptcp_sock *msk = mptcp_sk(sk);
433
434 if (!msk->first_pending)
435 return NULL;
436
437 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue)))
438 return NULL;
439
440 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
441 }
442
mptcp_rtx_head(struct sock * sk)443 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk)
444 {
445 struct mptcp_sock *msk = mptcp_sk(sk);
446
447 if (msk->snd_una == msk->snd_nxt)
448 return NULL;
449
450 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list);
451 }
452
453 struct csum_pseudo_header {
454 __be64 data_seq;
455 __be32 subflow_seq;
456 __be16 data_len;
457 __sum16 csum;
458 };
459
460 struct mptcp_subflow_request_sock {
461 struct tcp_request_sock sk;
462 u16 mp_capable : 1,
463 mp_join : 1,
464 backup : 1,
465 request_bkup : 1,
466 csum_reqd : 1,
467 allow_join_id0 : 1;
468 u8 local_id;
469 u8 remote_id;
470 u64 local_key;
471 u64 idsn;
472 u32 token;
473 u32 ssn_offset;
474 u64 thmac;
475 u32 local_nonce;
476 u32 remote_nonce;
477 struct mptcp_sock *msk;
478 struct hlist_nulls_node token_node;
479 };
480
481 static inline struct mptcp_subflow_request_sock *
mptcp_subflow_rsk(const struct request_sock * rsk)482 mptcp_subflow_rsk(const struct request_sock *rsk)
483 {
484 return (struct mptcp_subflow_request_sock *)rsk;
485 }
486
487 struct mptcp_delegated_action {
488 struct napi_struct napi;
489 local_lock_t bh_lock;
490 struct list_head head;
491 };
492
493 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
494
495 #define MPTCP_DELEGATE_SCHEDULED 0
496 #define MPTCP_DELEGATE_SEND 1
497 #define MPTCP_DELEGATE_ACK 2
498 #define MPTCP_DELEGATE_SNDBUF 3
499
500 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED))
501 /* MPTCP subflow context */
502 struct mptcp_subflow_context {
503 struct list_head node;/* conn_list of subflows */
504
505 struct_group(reset,
506
507 unsigned long avg_pacing_rate; /* protected by msk socket lock */
508 u64 local_key;
509 u64 remote_key;
510 u64 idsn;
511 u64 map_seq;
512 u64 rcv_wnd_sent;
513 u32 snd_isn;
514 u32 token;
515 u32 rel_write_seq;
516 u32 map_subflow_seq;
517 u32 ssn_offset;
518 u32 map_data_len;
519 __wsum map_data_csum;
520 u32 map_csum_len;
521 u32 request_mptcp : 1, /* send MP_CAPABLE */
522 request_join : 1, /* send MP_JOIN */
523 request_bkup : 1,
524 mp_capable : 1, /* remote is MPTCP capable */
525 mp_join : 1, /* remote is JOINing */
526 pm_notified : 1, /* PM hook called for established status */
527 conn_finished : 1,
528 map_valid : 1,
529 map_csum_reqd : 1,
530 map_data_fin : 1,
531 mpc_map : 1,
532 backup : 1,
533 send_mp_prio : 1,
534 send_mp_fail : 1,
535 send_fastclose : 1,
536 send_infinite_map : 1,
537 remote_key_valid : 1, /* received the peer key from */
538 disposable : 1, /* ctx can be free at ulp release time */
539 stale : 1, /* unable to snd/rcv data, do not use for xmit */
540 valid_csum_seen : 1, /* at least one csum validated */
541 is_mptfo : 1, /* subflow is doing TFO */
542 close_event_done : 1, /* has done the post-closed part */
543 mpc_drop : 1, /* the MPC option has been dropped in a rtx */
544 __unused : 9;
545 bool data_avail;
546 bool scheduled;
547 bool pm_listener; /* a listener managed by the kernel PM? */
548 bool fully_established; /* path validated */
549 u32 remote_nonce;
550 u64 thmac;
551 u32 local_nonce;
552 u32 remote_token;
553 union {
554 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */
555 u64 iasn; /* initial ack sequence number, MPC subflows only */
556 };
557 s16 local_id; /* if negative not initialized yet */
558 u8 remote_id;
559 u8 reset_seen:1;
560 u8 reset_transient:1;
561 u8 reset_reason:4;
562 u8 stale_count;
563
564 u32 subflow_id;
565
566 long delegated_status;
567 unsigned long fail_tout;
568
569 );
570
571 struct list_head delegated_node; /* link into delegated_action, protected by local BH */
572
573 u32 setsockopt_seq;
574 u32 stale_rcv_tstamp;
575 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf,
576 * protected by the msk socket lock
577 */
578
579 struct sock *tcp_sock; /* tcp sk backpointer */
580 struct sock *conn; /* parent mptcp_sock */
581 const struct inet_connection_sock_af_ops *icsk_af_ops;
582 void (*tcp_state_change)(struct sock *sk);
583 void (*tcp_error_report)(struct sock *sk);
584
585 struct rcu_head rcu;
586 };
587
588 static inline struct mptcp_subflow_context *
mptcp_subflow_ctx(const struct sock * sk)589 mptcp_subflow_ctx(const struct sock *sk)
590 {
591 const struct inet_connection_sock *icsk = inet_csk(sk);
592
593 /* Use RCU on icsk_ulp_data only for sock diag code */
594 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data;
595 }
596
597 static inline struct sock *
mptcp_subflow_tcp_sock(const struct mptcp_subflow_context * subflow)598 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
599 {
600 return subflow->tcp_sock;
601 }
602
603 static inline void
mptcp_subflow_ctx_reset(struct mptcp_subflow_context * subflow)604 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow)
605 {
606 memset(&subflow->reset, 0, sizeof(subflow->reset));
607 subflow->request_mptcp = 1;
608 WRITE_ONCE(subflow->local_id, -1);
609 }
610
611 /* Convert reset reasons in MPTCP to enum sk_rst_reason type */
612 static inline enum sk_rst_reason
sk_rst_convert_mptcp_reason(u32 reason)613 sk_rst_convert_mptcp_reason(u32 reason)
614 {
615 switch (reason) {
616 case MPTCP_RST_EUNSPEC:
617 return SK_RST_REASON_MPTCP_RST_EUNSPEC;
618 case MPTCP_RST_EMPTCP:
619 return SK_RST_REASON_MPTCP_RST_EMPTCP;
620 case MPTCP_RST_ERESOURCE:
621 return SK_RST_REASON_MPTCP_RST_ERESOURCE;
622 case MPTCP_RST_EPROHIBIT:
623 return SK_RST_REASON_MPTCP_RST_EPROHIBIT;
624 case MPTCP_RST_EWQ2BIG:
625 return SK_RST_REASON_MPTCP_RST_EWQ2BIG;
626 case MPTCP_RST_EBADPERF:
627 return SK_RST_REASON_MPTCP_RST_EBADPERF;
628 case MPTCP_RST_EMIDDLEBOX:
629 return SK_RST_REASON_MPTCP_RST_EMIDDLEBOX;
630 default:
631 /* It should not happen, or else errors may occur
632 * in MPTCP layer
633 */
634 return SK_RST_REASON_ERROR;
635 }
636 }
637
638 static inline void
mptcp_send_active_reset_reason(struct sock * sk)639 mptcp_send_active_reset_reason(struct sock *sk)
640 {
641 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
642 enum sk_rst_reason reason;
643
644 reason = sk_rst_convert_mptcp_reason(subflow->reset_reason);
645 tcp_send_active_reset(sk, GFP_ATOMIC, reason);
646 }
647
648 static inline u64
mptcp_subflow_get_map_offset(const struct mptcp_subflow_context * subflow)649 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow)
650 {
651 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq -
652 subflow->ssn_offset -
653 subflow->map_subflow_seq;
654 }
655
656 static inline u64
mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context * subflow)657 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow)
658 {
659 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow);
660 }
661
662 void mptcp_subflow_process_delegated(struct sock *ssk, long actions);
663
mptcp_subflow_delegate(struct mptcp_subflow_context * subflow,int action)664 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action)
665 {
666 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action);
667 struct mptcp_delegated_action *delegated;
668 bool schedule;
669
670 /* the caller held the subflow bh socket lock */
671 lockdep_assert_in_softirq();
672
673 /* The implied barrier pairs with tcp_release_cb_override()
674 * mptcp_napi_poll(), and ensures the below list check sees list
675 * updates done prior to delegated status bits changes
676 */
677 old = set_mask_bits(&subflow->delegated_status, 0, set_bits);
678 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) {
679 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node)))
680 return;
681
682 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock);
683 delegated = this_cpu_ptr(&mptcp_delegated_actions);
684 schedule = list_empty(&delegated->head);
685 list_add_tail(&subflow->delegated_node, &delegated->head);
686 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock);
687 sock_hold(mptcp_subflow_tcp_sock(subflow));
688 if (schedule)
689 napi_schedule(&delegated->napi);
690 }
691 }
692
693 static inline struct mptcp_subflow_context *
mptcp_subflow_delegated_next(struct mptcp_delegated_action * delegated)694 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated)
695 {
696 struct mptcp_subflow_context *ret;
697
698 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock);
699 if (list_empty(&delegated->head)) {
700 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock);
701 return NULL;
702 }
703
704 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node);
705 list_del_init(&ret->delegated_node);
706 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock);
707 return ret;
708 }
709
710 int mptcp_is_enabled(const struct net *net);
711 unsigned int mptcp_get_add_addr_timeout(const struct net *net);
712 int mptcp_is_checksum_enabled(const struct net *net);
713 int mptcp_allow_join_id0(const struct net *net);
714 unsigned int mptcp_stale_loss_cnt(const struct net *net);
715 unsigned int mptcp_close_timeout(const struct sock *sk);
716 int mptcp_get_pm_type(const struct net *net);
717 const char *mptcp_get_path_manager(const struct net *net);
718 const char *mptcp_get_scheduler(const struct net *net);
719
720 void mptcp_active_disable(struct sock *sk);
721 bool mptcp_active_should_disable(struct sock *ssk);
722 void mptcp_active_enable(struct sock *sk);
723
724 void mptcp_get_available_schedulers(char *buf, size_t maxlen);
725 void __mptcp_subflow_fully_established(struct mptcp_sock *msk,
726 struct mptcp_subflow_context *subflow,
727 const struct mptcp_options_received *mp_opt);
728 bool __mptcp_retransmit_pending_data(struct sock *sk);
729 void mptcp_check_and_set_pending(struct sock *sk);
730 void __mptcp_push_pending(struct sock *sk, unsigned int flags);
731 bool mptcp_subflow_data_available(struct sock *sk);
732 void __init mptcp_subflow_init(void);
733 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how);
734 void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
735 struct mptcp_subflow_context *subflow);
736 void __mptcp_subflow_send_ack(struct sock *ssk);
737 void mptcp_subflow_reset(struct sock *ssk);
738 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk);
739 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
740 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk);
741 bool __mptcp_close(struct sock *sk, long timeout);
742 void mptcp_cancel_work(struct sock *sk);
743 void __mptcp_unaccepted_force_close(struct sock *sk);
744 void mptcp_set_state(struct sock *sk, int state);
745
746 bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
747 const struct mptcp_addr_info *b, bool use_port);
748 void mptcp_local_address(const struct sock_common *skc,
749 struct mptcp_addr_info *addr);
750 void mptcp_remote_address(const struct sock_common *skc,
751 struct mptcp_addr_info *addr);
752
753 /* called with sk socket lock held */
754 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_pm_local *local,
755 const struct mptcp_addr_info *remote);
756 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family,
757 struct socket **new_sock);
758 void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
759 struct sockaddr_storage *addr,
760 unsigned short family);
761 struct mptcp_sched_ops *mptcp_sched_find(const char *name);
762 int mptcp_validate_scheduler(struct mptcp_sched_ops *sched);
763 int mptcp_register_scheduler(struct mptcp_sched_ops *sched);
764 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched);
765 void mptcp_sched_init(void);
766 int mptcp_init_sched(struct mptcp_sock *msk,
767 struct mptcp_sched_ops *sched);
768 void mptcp_release_sched(struct mptcp_sock *msk);
769 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
770 bool scheduled);
771 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk);
772 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk);
773 int mptcp_sched_get_send(struct mptcp_sock *msk);
774 int mptcp_sched_get_retrans(struct mptcp_sock *msk);
775
mptcp_data_avail(const struct mptcp_sock * msk)776 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk)
777 {
778 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed);
779 }
780
mptcp_epollin_ready(const struct sock * sk)781 static inline bool mptcp_epollin_ready(const struct sock *sk)
782 {
783 u64 data_avail = mptcp_data_avail(mptcp_sk(sk));
784
785 if (!data_avail)
786 return false;
787
788 /* mptcp doesn't have to deal with small skbs in the receive queue,
789 * as it can always coalesce them
790 */
791 return (data_avail >= sk->sk_rcvlowat) ||
792 tcp_under_memory_pressure(sk);
793 }
794
795 int mptcp_set_rcvlowat(struct sock *sk, int val);
796
__tcp_can_send(const struct sock * ssk)797 static inline bool __tcp_can_send(const struct sock *ssk)
798 {
799 /* only send if our side has not closed yet */
800 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT));
801 }
802
__mptcp_subflow_active(struct mptcp_subflow_context * subflow)803 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow)
804 {
805 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */
806 if (subflow->request_join && !READ_ONCE(subflow->fully_established))
807 return false;
808
809 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow));
810 }
811
812 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow);
813
814 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow);
815
816 void mptcp_subflow_drop_ctx(struct sock *ssk);
817
mptcp_subflow_tcp_fallback(struct sock * sk,struct mptcp_subflow_context * ctx)818 static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
819 struct mptcp_subflow_context *ctx)
820 {
821 sk->sk_data_ready = sock_def_readable;
822 sk->sk_state_change = ctx->tcp_state_change;
823 sk->sk_write_space = sk_stream_write_space;
824 sk->sk_error_report = ctx->tcp_error_report;
825
826 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
827 }
828
829 void __init mptcp_proto_init(void);
830 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
831 int __init mptcp_proto_v6_init(void);
832 #endif
833
834 struct sock *mptcp_sk_clone_init(const struct sock *sk,
835 const struct mptcp_options_received *mp_opt,
836 struct sock *ssk,
837 struct request_sock *req);
838 void mptcp_get_options(const struct sk_buff *skb,
839 struct mptcp_options_received *mp_opt);
840
841 void mptcp_finish_connect(struct sock *sk);
842 void __mptcp_sync_state(struct sock *sk, int state);
843 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout);
844
mptcp_stop_tout_timer(struct sock * sk)845 static inline void mptcp_stop_tout_timer(struct sock *sk)
846 {
847 if (!inet_csk(sk)->icsk_mtup.probe_timestamp)
848 return;
849
850 sk_stop_timer(sk, &sk->sk_timer);
851 inet_csk(sk)->icsk_mtup.probe_timestamp = 0;
852 }
853
mptcp_set_close_tout(struct sock * sk,unsigned long tout)854 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout)
855 {
856 /* avoid 0 timestamp, as that means no close timeout */
857 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1;
858 }
859
mptcp_start_tout_timer(struct sock * sk)860 static inline void mptcp_start_tout_timer(struct sock *sk)
861 {
862 mptcp_set_close_tout(sk, tcp_jiffies32);
863 mptcp_reset_tout_timer(mptcp_sk(sk), 0);
864 }
865
mptcp_is_fully_established(struct sock * sk)866 static inline bool mptcp_is_fully_established(struct sock *sk)
867 {
868 return inet_sk_state_load(sk) == TCP_ESTABLISHED &&
869 READ_ONCE(mptcp_sk(sk)->fully_established);
870 }
871
872 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk);
873 void mptcp_data_ready(struct sock *sk, struct sock *ssk);
874 bool mptcp_finish_join(struct sock *sk);
875 bool mptcp_schedule_work(struct sock *sk);
876 int mptcp_setsockopt(struct sock *sk, int level, int optname,
877 sockptr_t optval, unsigned int optlen);
878 int mptcp_getsockopt(struct sock *sk, int level, int optname,
879 char __user *optval, int __user *option);
880
881 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq);
mptcp_expand_seq(u64 old_seq,u64 cur_seq,bool use_64bit)882 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit)
883 {
884 if (use_64bit)
885 return cur_seq;
886
887 return __mptcp_expand_seq(old_seq, cur_seq);
888 }
889 void __mptcp_check_push(struct sock *sk, struct sock *ssk);
890 void __mptcp_data_acked(struct sock *sk);
891 void __mptcp_error_report(struct sock *sk);
892 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)893 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk)
894 {
895 return READ_ONCE(msk->snd_data_fin_enable) &&
896 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt);
897 }
898
mptcp_notsent_lowat(const struct sock * sk)899 static inline u32 mptcp_notsent_lowat(const struct sock *sk)
900 {
901 struct net *net = sock_net(sk);
902 u32 val;
903
904 val = READ_ONCE(mptcp_sk(sk)->notsent_lowat);
905 return val ?: READ_ONCE(net->ipv4.sysctl_tcp_notsent_lowat);
906 }
907
mptcp_stream_memory_free(const struct sock * sk,int wake)908 static inline bool mptcp_stream_memory_free(const struct sock *sk, int wake)
909 {
910 const struct mptcp_sock *msk = mptcp_sk(sk);
911 u32 notsent_bytes;
912
913 notsent_bytes = READ_ONCE(msk->write_seq) - READ_ONCE(msk->snd_nxt);
914 return (notsent_bytes << wake) < mptcp_notsent_lowat(sk);
915 }
916
__mptcp_stream_is_writeable(const struct sock * sk,int wake)917 static inline bool __mptcp_stream_is_writeable(const struct sock *sk, int wake)
918 {
919 return mptcp_stream_memory_free(sk, wake) &&
920 __sk_stream_is_writeable(sk, wake);
921 }
922
mptcp_write_space(struct sock * sk)923 static inline void mptcp_write_space(struct sock *sk)
924 {
925 /* pairs with memory barrier in mptcp_poll */
926 smp_mb();
927 if (mptcp_stream_memory_free(sk, 1))
928 sk_stream_write_space(sk);
929 }
930
__mptcp_sync_sndbuf(struct sock * sk)931 static inline void __mptcp_sync_sndbuf(struct sock *sk)
932 {
933 struct mptcp_subflow_context *subflow;
934 int ssk_sndbuf, new_sndbuf;
935
936 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
937 return;
938
939 new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]);
940 mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
941 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf);
942
943 subflow->cached_sndbuf = ssk_sndbuf;
944 new_sndbuf += ssk_sndbuf;
945 }
946
947 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */
948 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf);
949 mptcp_write_space(sk);
950 }
951
952 /* The called held both the msk socket and the subflow socket locks,
953 * possibly under BH
954 */
__mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)955 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
956 {
957 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
958
959 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf)
960 __mptcp_sync_sndbuf(sk);
961 }
962
963 /* the caller held only the subflow socket lock, either in process or
964 * BH context. Additionally this can be called under the msk data lock,
965 * so we can't acquire such lock here: let the delegate action acquires
966 * the needed locks in suitable order.
967 */
mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)968 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
969 {
970 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
971
972 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf))
973 return;
974
975 local_bh_disable();
976 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF);
977 local_bh_enable();
978 }
979
980 void mptcp_destroy_common(struct mptcp_sock *msk);
981
982 #define MPTCP_TOKEN_MAX_RETRIES 4
983
984 void __init mptcp_token_init(void);
mptcp_token_init_request(struct request_sock * req)985 static inline void mptcp_token_init_request(struct request_sock *req)
986 {
987 mptcp_subflow_rsk(req)->token_node.pprev = NULL;
988 }
989
990 int mptcp_token_new_request(struct request_sock *req);
991 void mptcp_token_destroy_request(struct request_sock *req);
992 int mptcp_token_new_connect(struct sock *ssk);
993 void mptcp_token_accept(struct mptcp_subflow_request_sock *r,
994 struct mptcp_sock *msk);
995 bool mptcp_token_exists(u32 token);
996 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token);
997 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot,
998 long *s_num);
999 void mptcp_token_destroy(struct mptcp_sock *msk);
1000
1001 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
1002
1003 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac);
1004 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum);
1005
1006 void __init mptcp_pm_init(void);
1007 void mptcp_pm_data_init(struct mptcp_sock *msk);
1008 void mptcp_pm_data_reset(struct mptcp_sock *msk);
1009 void mptcp_pm_destroy(struct mptcp_sock *msk);
1010 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
1011 struct mptcp_addr_info *addr);
1012 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
1013 bool require_family,
1014 struct mptcp_pm_addr_entry *entry);
1015 bool mptcp_pm_addr_families_match(const struct sock *sk,
1016 const struct mptcp_addr_info *loc,
1017 const struct mptcp_addr_info *rem);
1018 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
1019 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side);
1020 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk);
1021 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk);
1022 void mptcp_pm_connection_closed(struct mptcp_sock *msk);
1023 void mptcp_pm_subflow_established(struct mptcp_sock *msk);
1024 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk);
1025 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk,
1026 const struct mptcp_subflow_context *subflow);
1027 void mptcp_pm_add_addr_received(const struct sock *ssk,
1028 const struct mptcp_addr_info *addr);
1029 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
1030 const struct mptcp_addr_info *addr);
1031 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk);
1032 void mptcp_pm_send_ack(struct mptcp_sock *msk,
1033 struct mptcp_subflow_context *subflow,
1034 bool prio, bool backup);
1035 void mptcp_pm_addr_send_ack(struct mptcp_sock *msk);
1036 void mptcp_pm_nl_rm_addr(struct mptcp_sock *msk, u8 rm_id);
1037 void mptcp_pm_rm_subflow(struct mptcp_sock *msk,
1038 const struct mptcp_rm_list *rm_list);
1039 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
1040 const struct mptcp_rm_list *rm_list);
1041 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
1042 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
1043 int mptcp_pm_mp_prio_send_ack(struct mptcp_sock *msk,
1044 struct mptcp_addr_info *addr,
1045 struct mptcp_addr_info *rem,
1046 u8 bkup);
1047 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
1048 const struct mptcp_addr_info *addr);
1049 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
1050 struct mptcp_pm_add_entry *
1051 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
1052 const struct mptcp_addr_info *addr, bool check_id);
1053 bool mptcp_lookup_subflow_by_saddr(const struct list_head *list,
1054 const struct mptcp_addr_info *saddr);
1055 bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk,
1056 const struct mptcp_addr_info *addr);
1057 int mptcp_pm_nl_set_flags(struct mptcp_pm_addr_entry *local,
1058 struct genl_info *info);
1059 int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local,
1060 struct genl_info *info);
1061 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
1062 const struct mptcp_addr_info *addr,
1063 bool echo);
1064 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
1065 void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
1066 struct mptcp_pm_addr_entry *entry);
1067
1068 /* the default path manager, used in mptcp_pm_unregister */
1069 extern struct mptcp_pm_ops mptcp_pm_kernel;
1070
1071 struct mptcp_pm_ops *mptcp_pm_find(const char *name);
1072 int mptcp_pm_register(struct mptcp_pm_ops *pm_ops);
1073 void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops);
1074 int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops);
1075 void mptcp_pm_get_available(char *buf, size_t maxlen);
1076
1077 void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk);
1078
1079 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
1080 const struct sock *ssk, gfp_t gfp);
1081 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info);
1082 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
1083 void mptcp_event_pm_listener(const struct sock *ssk,
1084 enum mptcp_event_type event);
1085 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk);
1086
1087 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow,
1088 struct request_sock *req);
1089 int mptcp_pm_genl_fill_addr(struct sk_buff *msg,
1090 struct netlink_callback *cb,
1091 struct mptcp_pm_addr_entry *entry);
1092
mptcp_pm_should_add_signal(struct mptcp_sock * msk)1093 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk)
1094 {
1095 return READ_ONCE(msk->pm.addr_signal) &
1096 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
1097 }
1098
mptcp_pm_should_add_signal_addr(struct mptcp_sock * msk)1099 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk)
1100 {
1101 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL);
1102 }
1103
mptcp_pm_should_add_signal_echo(struct mptcp_sock * msk)1104 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk)
1105 {
1106 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO);
1107 }
1108
mptcp_pm_should_rm_signal(struct mptcp_sock * msk)1109 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)
1110 {
1111 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL);
1112 }
1113
mptcp_pm_is_userspace(const struct mptcp_sock * msk)1114 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk)
1115 {
1116 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE;
1117 }
1118
mptcp_pm_is_kernel(const struct mptcp_sock * msk)1119 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk)
1120 {
1121 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL;
1122 }
1123
mptcp_add_addr_len(int family,bool echo,bool port)1124 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port)
1125 {
1126 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
1127
1128 if (family == AF_INET6)
1129 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
1130 if (!echo)
1131 len += MPTCPOPT_THMAC_LEN;
1132 /* account for 2 trailing 'nop' options */
1133 if (port)
1134 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
1135
1136 return len;
1137 }
1138
mptcp_rm_addr_len(const struct mptcp_rm_list * rm_list)1139 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
1140 {
1141 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX)
1142 return -EINVAL;
1143
1144 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
1145 }
1146
1147 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
1148 unsigned int opt_size, unsigned int remaining,
1149 struct mptcp_addr_info *addr, bool *echo,
1150 bool *drop_other_suboptions);
1151 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
1152 struct mptcp_rm_list *rm_list);
1153 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
1154 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk,
1155 struct mptcp_pm_addr_entry *skc);
1156 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk,
1157 struct mptcp_pm_addr_entry *skc);
1158 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc);
1159 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1160 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1161 int mptcp_pm_nl_dump_addr(struct sk_buff *msg,
1162 struct netlink_callback *cb);
1163 int mptcp_userspace_pm_dump_addr(struct sk_buff *msg,
1164 struct netlink_callback *cb);
1165 int mptcp_pm_nl_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
1166 struct genl_info *info);
1167 int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
1168 struct genl_info *info);
1169
subflow_get_local_id(const struct mptcp_subflow_context * subflow)1170 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow)
1171 {
1172 int local_id = READ_ONCE(subflow->local_id);
1173
1174 if (local_id < 0)
1175 return 0;
1176 return local_id;
1177 }
1178
1179 void __init mptcp_pm_kernel_register(void);
1180 void __init mptcp_pm_userspace_register(void);
1181 void __init mptcp_pm_nl_init(void);
1182 void mptcp_pm_worker(struct mptcp_sock *msk);
1183 void __mptcp_pm_kernel_worker(struct mptcp_sock *msk);
1184 u8 mptcp_pm_get_endp_signal_max(const struct mptcp_sock *msk);
1185 u8 mptcp_pm_get_endp_subflow_max(const struct mptcp_sock *msk);
1186 u8 mptcp_pm_get_endp_laminar_max(const struct mptcp_sock *msk);
1187 u8 mptcp_pm_get_limit_add_addr_accepted(const struct mptcp_sock *msk);
1188 u8 mptcp_pm_get_limit_extra_subflows(const struct mptcp_sock *msk);
1189
1190 /* called under PM lock */
__mptcp_pm_close_subflow(struct mptcp_sock * msk)1191 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk)
1192 {
1193 if (--msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk))
1194 WRITE_ONCE(msk->pm.accept_subflow, true);
1195 }
1196
mptcp_pm_close_subflow(struct mptcp_sock * msk)1197 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk)
1198 {
1199 spin_lock_bh(&msk->pm.lock);
1200 __mptcp_pm_close_subflow(msk);
1201 spin_unlock_bh(&msk->pm.lock);
1202 }
1203
mptcp_pm_add_addr_c_flag_case(struct mptcp_sock * msk)1204 static inline bool mptcp_pm_add_addr_c_flag_case(struct mptcp_sock *msk)
1205 {
1206 return READ_ONCE(msk->pm.remote_deny_join_id0) &&
1207 msk->pm.local_addr_used == 0 &&
1208 mptcp_pm_get_limit_add_addr_accepted(msk) == 0 &&
1209 msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk);
1210 }
1211
1212 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk);
1213
mptcp_get_ext(const struct sk_buff * skb)1214 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb)
1215 {
1216 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
1217 }
1218
1219 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);
1220
__mptcp_check_fallback(const struct mptcp_sock * msk)1221 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)
1222 {
1223 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags);
1224 }
1225
mptcp_check_fallback(const struct sock * sk)1226 static inline bool mptcp_check_fallback(const struct sock *sk)
1227 {
1228 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1229 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
1230
1231 return __mptcp_check_fallback(msk);
1232 }
1233
__mptcp_has_initial_subflow(const struct mptcp_sock * msk)1234 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk)
1235 {
1236 struct sock *ssk = READ_ONCE(msk->first);
1237
1238 return ssk && ((1 << inet_sk_state_load(ssk)) &
1239 (TCPF_ESTABLISHED | TCPF_SYN_SENT |
1240 TCPF_SYN_RECV | TCPF_LISTEN));
1241 }
1242
1243 bool __mptcp_try_fallback(struct mptcp_sock *msk, int fb_mib);
1244
mptcp_try_fallback(struct sock * ssk,int fb_mib)1245 static inline bool mptcp_try_fallback(struct sock *ssk, int fb_mib)
1246 {
1247 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1248 struct sock *sk = subflow->conn;
1249 struct mptcp_sock *msk;
1250
1251 msk = mptcp_sk(sk);
1252 if (!__mptcp_try_fallback(msk, fb_mib))
1253 return false;
1254 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) {
1255 gfp_t saved_allocation = ssk->sk_allocation;
1256
1257 /* we are in a atomic (BH) scope, override ssk default for data
1258 * fin allocation
1259 */
1260 ssk->sk_allocation = GFP_ATOMIC;
1261 ssk->sk_shutdown |= SEND_SHUTDOWN;
1262 tcp_shutdown(ssk, SEND_SHUTDOWN);
1263 ssk->sk_allocation = saved_allocation;
1264 }
1265 return true;
1266 }
1267
mptcp_early_fallback(struct mptcp_sock * msk,struct mptcp_subflow_context * subflow,int fb_mib)1268 static inline void mptcp_early_fallback(struct mptcp_sock *msk,
1269 struct mptcp_subflow_context *subflow,
1270 int fb_mib)
1271 {
1272 subflow->request_mptcp = 0;
1273 WARN_ON_ONCE(!__mptcp_try_fallback(msk, fb_mib));
1274 }
1275
mptcp_check_infinite_map(struct sk_buff * skb)1276 static inline bool mptcp_check_infinite_map(struct sk_buff *skb)
1277 {
1278 struct mptcp_ext *mpext;
1279
1280 mpext = skb ? mptcp_get_ext(skb) : NULL;
1281 if (mpext && mpext->infinite_map)
1282 return true;
1283
1284 return false;
1285 }
1286
is_active_ssk(struct mptcp_subflow_context * subflow)1287 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow)
1288 {
1289 return (subflow->request_mptcp || subflow->request_join);
1290 }
1291
subflow_simultaneous_connect(struct sock * sk)1292 static inline bool subflow_simultaneous_connect(struct sock *sk)
1293 {
1294 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1295
1296 return (1 << sk->sk_state) &
1297 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) &&
1298 is_active_ssk(subflow) &&
1299 !subflow->conn_finished;
1300 }
1301
1302 #ifdef CONFIG_SYN_COOKIES
1303 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1304 struct sk_buff *skb);
1305 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1306 struct sk_buff *skb);
1307 void __init mptcp_join_cookie_init(void);
1308 #else
1309 static inline void
subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1310 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1311 struct sk_buff *skb) {}
1312 static inline bool
mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1313 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1314 struct sk_buff *skb)
1315 {
1316 return false;
1317 }
1318
mptcp_join_cookie_init(void)1319 static inline void mptcp_join_cookie_init(void) {}
1320 #endif
1321
1322 #endif /* __MPTCP_PROTOCOL_H */
1323