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
16 #define MPTCP_SUPPORTED_VERSION 1
17
18 /* MPTCP option bits */
19 #define OPTION_MPTCP_MPC_SYN BIT(0)
20 #define OPTION_MPTCP_MPC_SYNACK BIT(1)
21 #define OPTION_MPTCP_MPC_ACK BIT(2)
22 #define OPTION_MPTCP_MPJ_SYN BIT(3)
23 #define OPTION_MPTCP_MPJ_SYNACK BIT(4)
24 #define OPTION_MPTCP_MPJ_ACK BIT(5)
25 #define OPTION_MPTCP_ADD_ADDR BIT(6)
26 #define OPTION_MPTCP_RM_ADDR BIT(7)
27 #define OPTION_MPTCP_FASTCLOSE BIT(8)
28 #define OPTION_MPTCP_PRIO BIT(9)
29 #define OPTION_MPTCP_RST BIT(10)
30 #define OPTION_MPTCP_DSS BIT(11)
31 #define OPTION_MPTCP_FAIL BIT(12)
32
33 #define OPTION_MPTCP_CSUMREQD BIT(13)
34
35 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \
36 OPTION_MPTCP_MPC_ACK)
37 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \
38 OPTION_MPTCP_MPJ_ACK)
39
40 /* MPTCP option subtypes */
41 #define MPTCPOPT_MP_CAPABLE 0
42 #define MPTCPOPT_MP_JOIN 1
43 #define MPTCPOPT_DSS 2
44 #define MPTCPOPT_ADD_ADDR 3
45 #define MPTCPOPT_RM_ADDR 4
46 #define MPTCPOPT_MP_PRIO 5
47 #define MPTCPOPT_MP_FAIL 6
48 #define MPTCPOPT_MP_FASTCLOSE 7
49 #define MPTCPOPT_RST 8
50
51 /* MPTCP suboption lengths */
52 #define TCPOLEN_MPTCP_MPC_SYN 4
53 #define TCPOLEN_MPTCP_MPC_SYNACK 12
54 #define TCPOLEN_MPTCP_MPC_ACK 20
55 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22
56 #define TCPOLEN_MPTCP_MPJ_SYN 12
57 #define TCPOLEN_MPTCP_MPJ_SYNACK 16
58 #define TCPOLEN_MPTCP_MPJ_ACK 24
59 #define TCPOLEN_MPTCP_DSS_BASE 4
60 #define TCPOLEN_MPTCP_DSS_ACK32 4
61 #define TCPOLEN_MPTCP_DSS_ACK64 8
62 #define TCPOLEN_MPTCP_DSS_MAP32 10
63 #define TCPOLEN_MPTCP_DSS_MAP64 14
64 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2
65 #define TCPOLEN_MPTCP_ADD_ADDR 16
66 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18
67 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8
68 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10
69 #define TCPOLEN_MPTCP_ADD_ADDR6 28
70 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30
71 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20
72 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22
73 #define TCPOLEN_MPTCP_PORT_LEN 2
74 #define TCPOLEN_MPTCP_PORT_ALIGN 2
75 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3
76 #define TCPOLEN_MPTCP_PRIO 3
77 #define TCPOLEN_MPTCP_PRIO_ALIGN 4
78 #define TCPOLEN_MPTCP_FASTCLOSE 12
79 #define TCPOLEN_MPTCP_RST 4
80 #define TCPOLEN_MPTCP_FAIL 12
81
82 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA)
83
84 /* MPTCP MP_JOIN flags */
85 #define MPTCPOPT_BACKUP BIT(0)
86 #define MPTCPOPT_THMAC_LEN 8
87
88 /* MPTCP MP_CAPABLE flags */
89 #define MPTCP_VERSION_MASK (0x0F)
90 #define MPTCP_CAP_CHECKSUM_REQD BIT(7)
91 #define MPTCP_CAP_EXTENSIBILITY BIT(6)
92 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5)
93 #define MPTCP_CAP_HMAC_SHA256 BIT(0)
94 #define MPTCP_CAP_FLAG_MASK (0x1F)
95
96 /* MPTCP DSS flags */
97 #define MPTCP_DSS_DATA_FIN BIT(4)
98 #define MPTCP_DSS_DSN64 BIT(3)
99 #define MPTCP_DSS_HAS_MAP BIT(2)
100 #define MPTCP_DSS_ACK64 BIT(1)
101 #define MPTCP_DSS_HAS_ACK BIT(0)
102 #define MPTCP_DSS_FLAG_MASK (0x1F)
103
104 /* MPTCP ADD_ADDR flags */
105 #define MPTCP_ADDR_ECHO BIT(0)
106
107 /* MPTCP MP_PRIO flags */
108 #define MPTCP_PRIO_BKUP BIT(0)
109
110 /* MPTCP TCPRST flags */
111 #define MPTCP_RST_TRANSIENT BIT(0)
112
113 /* MPTCP socket atomic flags */
114 #define MPTCP_NOSPACE 1
115 #define MPTCP_WORK_RTX 2
116 #define MPTCP_FALLBACK_DONE 4
117 #define MPTCP_WORK_CLOSE_SUBFLOW 5
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:1;
133 };
134
135 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0]))
136
before64(__u64 seq1,__u64 seq2)137 static inline bool before64(__u64 seq1, __u64 seq2)
138 {
139 return (__s64)(seq1 - seq2) < 0;
140 }
141
142 #define after64(seq2, seq1) before64(seq1, seq2)
143
144 struct mptcp_options_received {
145 u64 sndr_key;
146 u64 rcvr_key;
147 u64 data_ack;
148 u64 data_seq;
149 u32 subflow_seq;
150 u16 data_len;
151 __sum16 csum;
152 u16 suboptions;
153 u32 token;
154 u32 nonce;
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 u8 join_id;
168 u64 thmac;
169 u8 hmac[MPTCPOPT_HMAC_LEN];
170 struct mptcp_addr_info addr;
171 struct mptcp_rm_list rm_list;
172 u64 ahmac;
173 u64 fail_seq;
174 };
175
mptcp_option(u8 subopt,u8 len,u8 nib,u8 field)176 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field)
177 {
178 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) |
179 ((nib & 0xF) << 8) | field);
180 }
181
182 enum mptcp_pm_status {
183 MPTCP_PM_ADD_ADDR_RECEIVED,
184 MPTCP_PM_ADD_ADDR_SEND_ACK,
185 MPTCP_PM_RM_ADDR_RECEIVED,
186 MPTCP_PM_ESTABLISHED,
187 MPTCP_PM_SUBFLOW_ESTABLISHED,
188 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */
189 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is
190 * accounted int id_avail_bitmap
191 */
192 };
193
194 enum mptcp_pm_type {
195 MPTCP_PM_TYPE_KERNEL = 0,
196 MPTCP_PM_TYPE_USERSPACE,
197
198 __MPTCP_PM_TYPE_NR,
199 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1,
200 };
201
202 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */
203 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1)
204
205 enum mptcp_addr_signal_status {
206 MPTCP_ADD_ADDR_SIGNAL,
207 MPTCP_ADD_ADDR_ECHO,
208 MPTCP_RM_ADDR_SIGNAL,
209 };
210
211 /* max value of mptcp_addr_info.id */
212 #define MPTCP_PM_MAX_ADDR_ID U8_MAX
213
214 struct mptcp_pm_data {
215 struct mptcp_addr_info local;
216 struct mptcp_addr_info remote;
217 struct list_head anno_list;
218 struct list_head userspace_pm_local_addr_list;
219
220 spinlock_t lock; /*protects the whole PM data */
221
222 u8 addr_signal;
223 bool server_side;
224 bool work_pending;
225 bool accept_addr;
226 bool accept_subflow;
227 bool remote_deny_join_id0;
228 u8 add_addr_signaled;
229 u8 add_addr_accepted;
230 u8 local_addr_used;
231 u8 pm_type;
232 u8 subflows;
233 u8 status;
234 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
235 struct mptcp_rm_list rm_list_tx;
236 struct mptcp_rm_list rm_list_rx;
237 };
238
239 struct mptcp_pm_addr_entry {
240 struct list_head list;
241 struct mptcp_addr_info addr;
242 u8 flags;
243 int ifindex;
244 struct socket *lsk;
245 };
246
247 struct mptcp_data_frag {
248 struct list_head list;
249 u64 data_seq;
250 u16 data_len;
251 u16 offset;
252 u16 overhead;
253 u16 already_sent;
254 struct page *page;
255 };
256
257 /* MPTCP connection sock */
258 struct mptcp_sock {
259 /* inet_connection_sock must be the first member */
260 struct inet_connection_sock sk;
261 u64 local_key;
262 u64 remote_key;
263 u64 write_seq;
264 u64 bytes_sent;
265 u64 snd_nxt;
266 u64 bytes_received;
267 u64 ack_seq;
268 atomic64_t rcv_wnd_sent;
269 u64 rcv_data_fin_seq;
270 u64 bytes_retrans;
271 u64 bytes_consumed;
272 int rmem_fwd_alloc;
273 int snd_burst;
274 int old_wspace;
275 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq;
276 * recovery related fields are under data_lock
277 * protection
278 */
279 u64 bytes_acked;
280 u64 snd_una;
281 u64 wnd_end;
282 unsigned long timer_ival;
283 u32 token;
284 int rmem_released;
285 unsigned long flags;
286 unsigned long cb_flags;
287 bool recovery; /* closing subflow write queue reinjected */
288 bool can_ack;
289 bool fully_established;
290 bool rcv_data_fin;
291 bool snd_data_fin_enable;
292 bool rcv_fastclose;
293 bool use_64bit_ack; /* Set when we received a 64-bit DSN */
294 bool csum_enabled;
295 bool allow_infinite_fallback;
296 u8 pending_state; /* A subflow asked to set this sk_state,
297 * protected by the msk data lock
298 */
299 u8 mpc_endpoint_id;
300 u8 recvmsg_inq:1,
301 cork:1,
302 nodelay:1,
303 fastopening:1,
304 in_accept_queue:1,
305 free_first:1,
306 rcvspace_init:1;
307 int keepalive_cnt;
308 int keepalive_idle;
309 int keepalive_intvl;
310 struct work_struct work;
311 struct sk_buff *ooo_last_skb;
312 struct rb_root out_of_order_queue;
313 struct sk_buff_head receive_queue;
314 struct list_head conn_list;
315 struct list_head rtx_queue;
316 struct mptcp_data_frag *first_pending;
317 struct list_head join_list;
318 struct sock *first; /* The mptcp ops can safely dereference, using suitable
319 * ONCE annotation, the subflow outside the socket
320 * lock as such sock is freed after close().
321 */
322 struct mptcp_pm_data pm;
323 struct mptcp_sched_ops *sched;
324 struct {
325 u32 space; /* bytes copied in last measurement window */
326 u32 copied; /* bytes copied in this measurement window */
327 u64 time; /* start time of measurement window */
328 u64 rtt_us; /* last maximum rtt of subflows */
329 } rcvq_space;
330 u8 scaling_ratio;
331
332 u32 subflow_id;
333 u32 setsockopt_seq;
334 char ca_name[TCP_CA_NAME_MAX];
335 };
336
337 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock)
338 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock)
339
340 #define mptcp_for_each_subflow(__msk, __subflow) \
341 list_for_each_entry(__subflow, &((__msk)->conn_list), node)
342 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \
343 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node)
344
msk_owned_by_me(const struct mptcp_sock * msk)345 static inline void msk_owned_by_me(const struct mptcp_sock *msk)
346 {
347 sock_owned_by_me((const struct sock *)msk);
348 }
349
350 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk)
351
352 /* the msk socket don't use the backlog, also account for the bulk
353 * free memory
354 */
__mptcp_rmem(const struct sock * sk)355 static inline int __mptcp_rmem(const struct sock *sk)
356 {
357 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released);
358 }
359
mptcp_win_from_space(const struct sock * sk,int space)360 static inline int mptcp_win_from_space(const struct sock *sk, int space)
361 {
362 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space);
363 }
364
__mptcp_space(const struct sock * sk)365 static inline int __mptcp_space(const struct sock *sk)
366 {
367 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk));
368 }
369
mptcp_send_head(const struct sock * sk)370 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk)
371 {
372 const struct mptcp_sock *msk = mptcp_sk(sk);
373
374 return READ_ONCE(msk->first_pending);
375 }
376
mptcp_send_next(struct sock * sk)377 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk)
378 {
379 struct mptcp_sock *msk = mptcp_sk(sk);
380 struct mptcp_data_frag *cur;
381
382 cur = msk->first_pending;
383 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL :
384 list_next_entry(cur, list);
385 }
386
mptcp_pending_tail(const struct sock * sk)387 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
388 {
389 const struct mptcp_sock *msk = mptcp_sk(sk);
390
391 if (!msk->first_pending)
392 return NULL;
393
394 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue)))
395 return NULL;
396
397 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
398 }
399
mptcp_rtx_head(struct sock * sk)400 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk)
401 {
402 struct mptcp_sock *msk = mptcp_sk(sk);
403
404 if (msk->snd_una == READ_ONCE(msk->snd_nxt))
405 return NULL;
406
407 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list);
408 }
409
410 struct csum_pseudo_header {
411 __be64 data_seq;
412 __be32 subflow_seq;
413 __be16 data_len;
414 __sum16 csum;
415 };
416
417 struct mptcp_subflow_request_sock {
418 struct tcp_request_sock sk;
419 u16 mp_capable : 1,
420 mp_join : 1,
421 backup : 1,
422 request_bkup : 1,
423 csum_reqd : 1,
424 allow_join_id0 : 1;
425 u8 local_id;
426 u8 remote_id;
427 u64 local_key;
428 u64 idsn;
429 u32 token;
430 u32 ssn_offset;
431 u64 thmac;
432 u32 local_nonce;
433 u32 remote_nonce;
434 struct mptcp_sock *msk;
435 struct hlist_nulls_node token_node;
436 };
437
438 static inline struct mptcp_subflow_request_sock *
mptcp_subflow_rsk(const struct request_sock * rsk)439 mptcp_subflow_rsk(const struct request_sock *rsk)
440 {
441 return (struct mptcp_subflow_request_sock *)rsk;
442 }
443
444 enum mptcp_data_avail {
445 MPTCP_SUBFLOW_NODATA,
446 MPTCP_SUBFLOW_DATA_AVAIL,
447 };
448
449 struct mptcp_delegated_action {
450 struct napi_struct napi;
451 struct list_head head;
452 };
453
454 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
455
456 #define MPTCP_DELEGATE_SCHEDULED 0
457 #define MPTCP_DELEGATE_SEND 1
458 #define MPTCP_DELEGATE_ACK 2
459 #define MPTCP_DELEGATE_SNDBUF 3
460
461 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED))
462 /* MPTCP subflow context */
463 struct mptcp_subflow_context {
464 struct list_head node;/* conn_list of subflows */
465
466 struct_group(reset,
467
468 unsigned long avg_pacing_rate; /* protected by msk socket lock */
469 u64 local_key;
470 u64 remote_key;
471 u64 idsn;
472 u64 map_seq;
473 u32 snd_isn;
474 u32 token;
475 u32 rel_write_seq;
476 u32 map_subflow_seq;
477 u32 ssn_offset;
478 u32 map_data_len;
479 __wsum map_data_csum;
480 u32 map_csum_len;
481 u32 request_mptcp : 1, /* send MP_CAPABLE */
482 request_join : 1, /* send MP_JOIN */
483 request_bkup : 1,
484 mp_capable : 1, /* remote is MPTCP capable */
485 mp_join : 1, /* remote is JOINing */
486 fully_established : 1, /* path validated */
487 pm_notified : 1, /* PM hook called for established status */
488 conn_finished : 1,
489 map_valid : 1,
490 map_csum_reqd : 1,
491 map_data_fin : 1,
492 mpc_map : 1,
493 backup : 1,
494 send_mp_prio : 1,
495 send_mp_fail : 1,
496 send_fastclose : 1,
497 send_infinite_map : 1,
498 remote_key_valid : 1, /* received the peer key from */
499 disposable : 1, /* ctx can be free at ulp release time */
500 stale : 1, /* unable to snd/rcv data, do not use for xmit */
501 valid_csum_seen : 1, /* at least one csum validated */
502 is_mptfo : 1, /* subflow is doing TFO */
503 __unused : 10;
504 enum mptcp_data_avail data_avail;
505 bool scheduled;
506 u32 remote_nonce;
507 u64 thmac;
508 u32 local_nonce;
509 u32 remote_token;
510 union {
511 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */
512 u64 iasn; /* initial ack sequence number, MPC subflows only */
513 };
514 s16 local_id; /* if negative not initialized yet */
515 u8 remote_id;
516 u8 reset_seen:1;
517 u8 reset_transient:1;
518 u8 reset_reason:4;
519 u8 stale_count;
520
521 u32 subflow_id;
522
523 long delegated_status;
524 unsigned long fail_tout;
525
526 );
527
528 struct list_head delegated_node; /* link into delegated_action, protected by local BH */
529
530 u32 setsockopt_seq;
531 u32 stale_rcv_tstamp;
532 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf,
533 * protected by the msk socket lock
534 */
535
536 struct sock *tcp_sock; /* tcp sk backpointer */
537 struct sock *conn; /* parent mptcp_sock */
538 const struct inet_connection_sock_af_ops *icsk_af_ops;
539 void (*tcp_state_change)(struct sock *sk);
540 void (*tcp_error_report)(struct sock *sk);
541
542 struct rcu_head rcu;
543 };
544
545 static inline struct mptcp_subflow_context *
mptcp_subflow_ctx(const struct sock * sk)546 mptcp_subflow_ctx(const struct sock *sk)
547 {
548 struct inet_connection_sock *icsk = inet_csk(sk);
549
550 /* Use RCU on icsk_ulp_data only for sock diag code */
551 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data;
552 }
553
554 static inline struct sock *
mptcp_subflow_tcp_sock(const struct mptcp_subflow_context * subflow)555 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
556 {
557 return subflow->tcp_sock;
558 }
559
560 static inline void
mptcp_subflow_ctx_reset(struct mptcp_subflow_context * subflow)561 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow)
562 {
563 memset(&subflow->reset, 0, sizeof(subflow->reset));
564 subflow->request_mptcp = 1;
565 WRITE_ONCE(subflow->local_id, -1);
566 }
567
568 static inline u64
mptcp_subflow_get_map_offset(const struct mptcp_subflow_context * subflow)569 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow)
570 {
571 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq -
572 subflow->ssn_offset -
573 subflow->map_subflow_seq;
574 }
575
576 static inline u64
mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context * subflow)577 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow)
578 {
579 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow);
580 }
581
582 void mptcp_subflow_process_delegated(struct sock *ssk, long actions);
583
mptcp_subflow_delegate(struct mptcp_subflow_context * subflow,int action)584 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action)
585 {
586 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action);
587 struct mptcp_delegated_action *delegated;
588 bool schedule;
589
590 /* the caller held the subflow bh socket lock */
591 lockdep_assert_in_softirq();
592
593 /* The implied barrier pairs with tcp_release_cb_override()
594 * mptcp_napi_poll(), and ensures the below list check sees list
595 * updates done prior to delegated status bits changes
596 */
597 old = set_mask_bits(&subflow->delegated_status, 0, set_bits);
598 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) {
599 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node)))
600 return;
601
602 delegated = this_cpu_ptr(&mptcp_delegated_actions);
603 schedule = list_empty(&delegated->head);
604 list_add_tail(&subflow->delegated_node, &delegated->head);
605 sock_hold(mptcp_subflow_tcp_sock(subflow));
606 if (schedule)
607 napi_schedule(&delegated->napi);
608 }
609 }
610
611 static inline struct mptcp_subflow_context *
mptcp_subflow_delegated_next(struct mptcp_delegated_action * delegated)612 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated)
613 {
614 struct mptcp_subflow_context *ret;
615
616 if (list_empty(&delegated->head))
617 return NULL;
618
619 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node);
620 list_del_init(&ret->delegated_node);
621 return ret;
622 }
623
624 int mptcp_is_enabled(const struct net *net);
625 unsigned int mptcp_get_add_addr_timeout(const struct net *net);
626 int mptcp_is_checksum_enabled(const struct net *net);
627 int mptcp_allow_join_id0(const struct net *net);
628 unsigned int mptcp_stale_loss_cnt(const struct net *net);
629 int mptcp_get_pm_type(const struct net *net);
630 const char *mptcp_get_scheduler(const struct net *net);
631 void __mptcp_subflow_fully_established(struct mptcp_sock *msk,
632 struct mptcp_subflow_context *subflow,
633 const struct mptcp_options_received *mp_opt);
634 bool __mptcp_retransmit_pending_data(struct sock *sk);
635 void mptcp_check_and_set_pending(struct sock *sk);
636 void __mptcp_push_pending(struct sock *sk, unsigned int flags);
637 bool mptcp_subflow_data_available(struct sock *sk);
638 void __init mptcp_subflow_init(void);
639 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how);
640 void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
641 struct mptcp_subflow_context *subflow);
642 void __mptcp_subflow_send_ack(struct sock *ssk);
643 void mptcp_subflow_reset(struct sock *ssk);
644 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk);
645 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
646 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk);
647 bool __mptcp_close(struct sock *sk, long timeout);
648 void mptcp_cancel_work(struct sock *sk);
649 void __mptcp_unaccepted_force_close(struct sock *sk);
650 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk);
651 void mptcp_set_state(struct sock *sk, int state);
652
653 bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
654 const struct mptcp_addr_info *b, bool use_port);
655 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr);
656
657 /* called with sk socket lock held */
658 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc,
659 const struct mptcp_addr_info *remote);
660 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family,
661 struct socket **new_sock);
662 void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
663 struct sockaddr_storage *addr,
664 unsigned short family);
665 struct mptcp_sched_ops *mptcp_sched_find(const char *name);
666 int mptcp_register_scheduler(struct mptcp_sched_ops *sched);
667 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched);
668 void mptcp_sched_init(void);
669 int mptcp_init_sched(struct mptcp_sock *msk,
670 struct mptcp_sched_ops *sched);
671 void mptcp_release_sched(struct mptcp_sock *msk);
672 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
673 bool scheduled);
674 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk);
675 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk);
676 int mptcp_sched_get_send(struct mptcp_sock *msk);
677 int mptcp_sched_get_retrans(struct mptcp_sock *msk);
678
mptcp_data_avail(const struct mptcp_sock * msk)679 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk)
680 {
681 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed);
682 }
683
mptcp_epollin_ready(const struct sock * sk)684 static inline bool mptcp_epollin_ready(const struct sock *sk)
685 {
686 /* mptcp doesn't have to deal with small skbs in the receive queue,
687 * at it can always coalesce them
688 */
689 return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) ||
690 (mem_cgroup_sockets_enabled && sk->sk_memcg &&
691 mem_cgroup_under_socket_pressure(sk->sk_memcg)) ||
692 READ_ONCE(tcp_memory_pressure);
693 }
694
695 int mptcp_set_rcvlowat(struct sock *sk, int val);
696
__tcp_can_send(const struct sock * ssk)697 static inline bool __tcp_can_send(const struct sock *ssk)
698 {
699 /* only send if our side has not closed yet */
700 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT));
701 }
702
__mptcp_subflow_active(struct mptcp_subflow_context * subflow)703 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow)
704 {
705 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */
706 if (subflow->request_join && !subflow->fully_established)
707 return false;
708
709 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow));
710 }
711
712 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow);
713
714 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow);
715
716 void mptcp_subflow_drop_ctx(struct sock *ssk);
717
mptcp_subflow_tcp_fallback(struct sock * sk,struct mptcp_subflow_context * ctx)718 static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
719 struct mptcp_subflow_context *ctx)
720 {
721 sk->sk_data_ready = sock_def_readable;
722 sk->sk_state_change = ctx->tcp_state_change;
723 sk->sk_write_space = sk_stream_write_space;
724 sk->sk_error_report = ctx->tcp_error_report;
725
726 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
727 }
728
729 void __init mptcp_proto_init(void);
730 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
731 int __init mptcp_proto_v6_init(void);
732 #endif
733
734 struct sock *mptcp_sk_clone_init(const struct sock *sk,
735 const struct mptcp_options_received *mp_opt,
736 struct sock *ssk,
737 struct request_sock *req);
738 void mptcp_get_options(const struct sk_buff *skb,
739 struct mptcp_options_received *mp_opt);
740
741 void mptcp_finish_connect(struct sock *sk);
742 void __mptcp_sync_state(struct sock *sk, int state);
743 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout);
744
mptcp_stop_tout_timer(struct sock * sk)745 static inline void mptcp_stop_tout_timer(struct sock *sk)
746 {
747 if (!inet_csk(sk)->icsk_mtup.probe_timestamp)
748 return;
749
750 sk_stop_timer(sk, &sk->sk_timer);
751 inet_csk(sk)->icsk_mtup.probe_timestamp = 0;
752 }
753
mptcp_set_close_tout(struct sock * sk,unsigned long tout)754 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout)
755 {
756 /* avoid 0 timestamp, as that means no close timeout */
757 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1;
758 }
759
mptcp_start_tout_timer(struct sock * sk)760 static inline void mptcp_start_tout_timer(struct sock *sk)
761 {
762 mptcp_set_close_tout(sk, tcp_jiffies32);
763 mptcp_reset_tout_timer(mptcp_sk(sk), 0);
764 }
765
mptcp_is_fully_established(struct sock * sk)766 static inline bool mptcp_is_fully_established(struct sock *sk)
767 {
768 return inet_sk_state_load(sk) == TCP_ESTABLISHED &&
769 READ_ONCE(mptcp_sk(sk)->fully_established);
770 }
771
772 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk);
773 void mptcp_data_ready(struct sock *sk, struct sock *ssk);
774 bool mptcp_finish_join(struct sock *sk);
775 bool mptcp_schedule_work(struct sock *sk);
776 int mptcp_setsockopt(struct sock *sk, int level, int optname,
777 sockptr_t optval, unsigned int optlen);
778 int mptcp_getsockopt(struct sock *sk, int level, int optname,
779 char __user *optval, int __user *option);
780
781 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq);
mptcp_expand_seq(u64 old_seq,u64 cur_seq,bool use_64bit)782 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit)
783 {
784 if (use_64bit)
785 return cur_seq;
786
787 return __mptcp_expand_seq(old_seq, cur_seq);
788 }
789 void __mptcp_check_push(struct sock *sk, struct sock *ssk);
790 void __mptcp_data_acked(struct sock *sk);
791 void __mptcp_error_report(struct sock *sk);
792 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)793 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk)
794 {
795 return READ_ONCE(msk->snd_data_fin_enable) &&
796 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt);
797 }
798
mptcp_write_space(struct sock * sk)799 static inline void mptcp_write_space(struct sock *sk)
800 {
801 if (sk_stream_is_writeable(sk)) {
802 /* pairs with memory barrier in mptcp_poll */
803 smp_mb();
804 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags))
805 sk_stream_write_space(sk);
806 }
807 }
808
__mptcp_sync_sndbuf(struct sock * sk)809 static inline void __mptcp_sync_sndbuf(struct sock *sk)
810 {
811 struct mptcp_subflow_context *subflow;
812 int ssk_sndbuf, new_sndbuf;
813
814 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
815 return;
816
817 new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0];
818 mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
819 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf);
820
821 subflow->cached_sndbuf = ssk_sndbuf;
822 new_sndbuf += ssk_sndbuf;
823 }
824
825 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */
826 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf);
827 mptcp_write_space(sk);
828 }
829
830 /* The called held both the msk socket and the subflow socket locks,
831 * possibly under BH
832 */
__mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)833 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
834 {
835 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
836
837 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf)
838 __mptcp_sync_sndbuf(sk);
839 }
840
841 /* the caller held only the subflow socket lock, either in process or
842 * BH context. Additionally this can be called under the msk data lock,
843 * so we can't acquire such lock here: let the delegate action acquires
844 * the needed locks in suitable order.
845 */
mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)846 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
847 {
848 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
849
850 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf))
851 return;
852
853 local_bh_disable();
854 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF);
855 local_bh_enable();
856 }
857
858 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags);
859
860 #define MPTCP_TOKEN_MAX_RETRIES 4
861
862 void __init mptcp_token_init(void);
mptcp_token_init_request(struct request_sock * req)863 static inline void mptcp_token_init_request(struct request_sock *req)
864 {
865 mptcp_subflow_rsk(req)->token_node.pprev = NULL;
866 }
867
868 int mptcp_token_new_request(struct request_sock *req);
869 void mptcp_token_destroy_request(struct request_sock *req);
870 int mptcp_token_new_connect(struct sock *ssk);
871 void mptcp_token_accept(struct mptcp_subflow_request_sock *r,
872 struct mptcp_sock *msk);
873 bool mptcp_token_exists(u32 token);
874 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token);
875 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot,
876 long *s_num);
877 void mptcp_token_destroy(struct mptcp_sock *msk);
878
879 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
880
881 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac);
882 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum);
883
884 void __init mptcp_pm_init(void);
885 void mptcp_pm_data_init(struct mptcp_sock *msk);
886 void mptcp_pm_data_reset(struct mptcp_sock *msk);
887 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
888 struct mptcp_addr_info *addr);
889 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
890 bool require_family,
891 struct mptcp_pm_addr_entry *entry);
892 bool mptcp_pm_addr_families_match(const struct sock *sk,
893 const struct mptcp_addr_info *loc,
894 const struct mptcp_addr_info *rem);
895 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
896 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
897 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side);
898 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk);
899 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk);
900 void mptcp_pm_connection_closed(struct mptcp_sock *msk);
901 void mptcp_pm_subflow_established(struct mptcp_sock *msk);
902 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk);
903 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk,
904 const struct mptcp_subflow_context *subflow);
905 void mptcp_pm_add_addr_received(const struct sock *ssk,
906 const struct mptcp_addr_info *addr);
907 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
908 const struct mptcp_addr_info *addr);
909 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk);
910 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk);
911 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
912 const struct mptcp_rm_list *rm_list);
913 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
914 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
915 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
916 struct mptcp_addr_info *addr,
917 struct mptcp_addr_info *rem,
918 u8 bkup);
919 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
920 const struct mptcp_addr_info *addr);
921 void mptcp_pm_free_anno_list(struct mptcp_sock *msk);
922 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
923 struct mptcp_pm_add_entry *
924 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
925 const struct mptcp_addr_info *addr, bool check_id);
926 struct mptcp_pm_add_entry *
927 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
928 const struct mptcp_addr_info *addr);
929 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
930 unsigned int id,
931 u8 *flags, int *ifindex);
932 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id,
933 u8 *flags, int *ifindex);
934 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
935 unsigned int id,
936 u8 *flags, int *ifindex);
937 int mptcp_pm_set_flags(struct net *net, struct nlattr *token,
938 struct mptcp_pm_addr_entry *loc,
939 struct mptcp_pm_addr_entry *rem, u8 bkup);
940 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup);
941 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token,
942 struct mptcp_pm_addr_entry *loc,
943 struct mptcp_pm_addr_entry *rem, u8 bkup);
944 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
945 const struct mptcp_addr_info *addr,
946 bool echo);
947 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
948 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list);
949 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
950 struct list_head *rm_list);
951
952 void mptcp_free_local_addr_list(struct mptcp_sock *msk);
953 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info);
954 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info);
955 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info);
956 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info);
957
958 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
959 const struct sock *ssk, gfp_t gfp);
960 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info);
961 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
962 void mptcp_event_pm_listener(const struct sock *ssk,
963 enum mptcp_event_type event);
964 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk);
965
966 void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
967 const struct mptcp_options_received *mp_opt);
968 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow,
969 struct request_sock *req);
970
mptcp_pm_should_add_signal(struct mptcp_sock * msk)971 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk)
972 {
973 return READ_ONCE(msk->pm.addr_signal) &
974 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
975 }
976
mptcp_pm_should_add_signal_addr(struct mptcp_sock * msk)977 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk)
978 {
979 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL);
980 }
981
mptcp_pm_should_add_signal_echo(struct mptcp_sock * msk)982 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk)
983 {
984 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO);
985 }
986
mptcp_pm_should_rm_signal(struct mptcp_sock * msk)987 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)
988 {
989 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL);
990 }
991
mptcp_pm_is_userspace(const struct mptcp_sock * msk)992 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk)
993 {
994 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE;
995 }
996
mptcp_pm_is_kernel(const struct mptcp_sock * msk)997 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk)
998 {
999 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL;
1000 }
1001
mptcp_add_addr_len(int family,bool echo,bool port)1002 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port)
1003 {
1004 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
1005
1006 if (family == AF_INET6)
1007 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
1008 if (!echo)
1009 len += MPTCPOPT_THMAC_LEN;
1010 /* account for 2 trailing 'nop' options */
1011 if (port)
1012 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
1013
1014 return len;
1015 }
1016
mptcp_rm_addr_len(const struct mptcp_rm_list * rm_list)1017 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
1018 {
1019 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX)
1020 return -EINVAL;
1021
1022 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
1023 }
1024
1025 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
1026 unsigned int opt_size, unsigned int remaining,
1027 struct mptcp_addr_info *addr, bool *echo,
1028 bool *drop_other_suboptions);
1029 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
1030 struct mptcp_rm_list *rm_list);
1031 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
1032 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1033 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1034 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc);
1035 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1036 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1037
subflow_get_local_id(const struct mptcp_subflow_context * subflow)1038 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow)
1039 {
1040 int local_id = READ_ONCE(subflow->local_id);
1041
1042 if (local_id < 0)
1043 return 0;
1044 return local_id;
1045 }
1046
1047 void __init mptcp_pm_nl_init(void);
1048 void mptcp_pm_nl_work(struct mptcp_sock *msk);
1049 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk);
1050 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk);
1051 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk);
1052 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk);
1053
1054 /* called under PM lock */
__mptcp_pm_close_subflow(struct mptcp_sock * msk)1055 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk)
1056 {
1057 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk))
1058 WRITE_ONCE(msk->pm.accept_subflow, true);
1059 }
1060
mptcp_pm_close_subflow(struct mptcp_sock * msk)1061 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk)
1062 {
1063 spin_lock_bh(&msk->pm.lock);
1064 __mptcp_pm_close_subflow(msk);
1065 spin_unlock_bh(&msk->pm.lock);
1066 }
1067
1068 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk);
1069 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk);
1070
mptcp_get_ext(const struct sk_buff * skb)1071 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb)
1072 {
1073 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
1074 }
1075
1076 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);
1077
__mptcp_check_fallback(const struct mptcp_sock * msk)1078 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)
1079 {
1080 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags);
1081 }
1082
mptcp_check_fallback(const struct sock * sk)1083 static inline bool mptcp_check_fallback(const struct sock *sk)
1084 {
1085 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1086 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
1087
1088 return __mptcp_check_fallback(msk);
1089 }
1090
__mptcp_do_fallback(struct mptcp_sock * msk)1091 static inline void __mptcp_do_fallback(struct mptcp_sock *msk)
1092 {
1093 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) {
1094 pr_debug("TCP fallback already done (msk=%p)", msk);
1095 return;
1096 }
1097 set_bit(MPTCP_FALLBACK_DONE, &msk->flags);
1098 }
1099
mptcp_do_fallback(struct sock * ssk)1100 static inline void mptcp_do_fallback(struct sock *ssk)
1101 {
1102 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1103 struct sock *sk = subflow->conn;
1104 struct mptcp_sock *msk;
1105
1106 msk = mptcp_sk(sk);
1107 __mptcp_do_fallback(msk);
1108 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) {
1109 gfp_t saved_allocation = ssk->sk_allocation;
1110
1111 /* we are in a atomic (BH) scope, override ssk default for data
1112 * fin allocation
1113 */
1114 ssk->sk_allocation = GFP_ATOMIC;
1115 ssk->sk_shutdown |= SEND_SHUTDOWN;
1116 tcp_shutdown(ssk, SEND_SHUTDOWN);
1117 ssk->sk_allocation = saved_allocation;
1118 }
1119 }
1120
1121 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a)
1122
mptcp_check_infinite_map(struct sk_buff * skb)1123 static inline bool mptcp_check_infinite_map(struct sk_buff *skb)
1124 {
1125 struct mptcp_ext *mpext;
1126
1127 mpext = skb ? mptcp_get_ext(skb) : NULL;
1128 if (mpext && mpext->infinite_map)
1129 return true;
1130
1131 return false;
1132 }
1133
is_active_ssk(struct mptcp_subflow_context * subflow)1134 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow)
1135 {
1136 return (subflow->request_mptcp || subflow->request_join);
1137 }
1138
subflow_simultaneous_connect(struct sock * sk)1139 static inline bool subflow_simultaneous_connect(struct sock *sk)
1140 {
1141 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1142
1143 return (1 << sk->sk_state) &
1144 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) &&
1145 is_active_ssk(subflow) &&
1146 !subflow->conn_finished;
1147 }
1148
1149 #ifdef CONFIG_SYN_COOKIES
1150 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1151 struct sk_buff *skb);
1152 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1153 struct sk_buff *skb);
1154 void __init mptcp_join_cookie_init(void);
1155 #else
1156 static inline void
subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1157 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1158 struct sk_buff *skb) {}
1159 static inline bool
mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1160 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1161 struct sk_buff *skb)
1162 {
1163 return false;
1164 }
1165
mptcp_join_cookie_init(void)1166 static inline void mptcp_join_cookie_init(void) {}
1167 #endif
1168
1169 #endif /* __MPTCP_PROTOCOL_H */
1170