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: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_local {
240 struct mptcp_addr_info addr;
241 u8 flags;
242 int ifindex;
243 };
244
245 struct mptcp_pm_addr_entry {
246 struct list_head list;
247 struct mptcp_addr_info addr;
248 u8 flags;
249 int ifindex;
250 struct socket *lsk;
251 };
252
253 struct mptcp_data_frag {
254 struct list_head list;
255 u64 data_seq;
256 u16 data_len;
257 u16 offset;
258 u16 overhead;
259 u16 already_sent;
260 struct page *page;
261 };
262
263 /* MPTCP connection sock */
264 struct mptcp_sock {
265 /* inet_connection_sock must be the first member */
266 struct inet_connection_sock sk;
267 u64 local_key; /* protected by the first subflow socket lock
268 * lockless access read
269 */
270 u64 remote_key; /* same as above */
271 u64 write_seq;
272 u64 bytes_sent;
273 u64 snd_nxt;
274 u64 bytes_received;
275 u64 ack_seq;
276 atomic64_t rcv_wnd_sent;
277 u64 rcv_data_fin_seq;
278 u64 bytes_retrans;
279 u64 bytes_consumed;
280 int rmem_fwd_alloc;
281 int snd_burst;
282 int old_wspace;
283 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq;
284 * recovery related fields are under data_lock
285 * protection
286 */
287 u64 bytes_acked;
288 u64 snd_una;
289 u64 wnd_end;
290 u32 last_data_sent;
291 u32 last_data_recv;
292 u32 last_ack_recv;
293 unsigned long timer_ival;
294 u32 token;
295 int rmem_released;
296 unsigned long flags;
297 unsigned long cb_flags;
298 bool recovery; /* closing subflow write queue reinjected */
299 bool can_ack;
300 bool fully_established;
301 bool rcv_data_fin;
302 bool snd_data_fin_enable;
303 bool rcv_fastclose;
304 bool use_64bit_ack; /* Set when we received a 64-bit DSN */
305 bool csum_enabled;
306 bool allow_infinite_fallback;
307 u8 pending_state; /* A subflow asked to set this sk_state,
308 * protected by the msk data lock
309 */
310 u8 mpc_endpoint_id;
311 u8 recvmsg_inq:1,
312 cork:1,
313 nodelay:1,
314 fastopening:1,
315 in_accept_queue:1,
316 free_first:1,
317 rcvspace_init:1;
318 u32 notsent_lowat;
319 int keepalive_cnt;
320 int keepalive_idle;
321 int keepalive_intvl;
322 struct work_struct work;
323 struct sk_buff *ooo_last_skb;
324 struct rb_root out_of_order_queue;
325 struct sk_buff_head receive_queue;
326 struct list_head conn_list;
327 struct list_head rtx_queue;
328 struct mptcp_data_frag *first_pending;
329 struct list_head join_list;
330 struct sock *first; /* The mptcp ops can safely dereference, using suitable
331 * ONCE annotation, the subflow outside the socket
332 * lock as such sock is freed after close().
333 */
334 struct mptcp_pm_data pm;
335 struct mptcp_sched_ops *sched;
336 struct {
337 u32 space; /* bytes copied in last measurement window */
338 u32 copied; /* bytes copied in this measurement window */
339 u64 time; /* start time of measurement window */
340 u64 rtt_us; /* last maximum rtt of subflows */
341 } rcvq_space;
342 u8 scaling_ratio;
343
344 u32 subflow_id;
345 u32 setsockopt_seq;
346 char ca_name[TCP_CA_NAME_MAX];
347 };
348
349 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock)
350 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock)
351
352 #define mptcp_for_each_subflow(__msk, __subflow) \
353 list_for_each_entry(__subflow, &((__msk)->conn_list), node)
354 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \
355 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node)
356
357 extern struct genl_family mptcp_genl_family;
358
msk_owned_by_me(const struct mptcp_sock * msk)359 static inline void msk_owned_by_me(const struct mptcp_sock *msk)
360 {
361 sock_owned_by_me((const struct sock *)msk);
362 }
363
364 #ifdef CONFIG_DEBUG_NET
365 /* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */
366 #undef tcp_sk
367 #define tcp_sk(ptr) ({ \
368 typeof(ptr) _ptr = (ptr); \
369 WARN_ON(_ptr->sk_protocol != IPPROTO_TCP); \
370 container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk); \
371 })
372 #define mptcp_sk(ptr) ({ \
373 typeof(ptr) _ptr = (ptr); \
374 WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP); \
375 container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk); \
376 })
377
378 #else /* !CONFIG_DEBUG_NET */
379 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk)
380 #endif
381
382 /* the msk socket don't use the backlog, also account for the bulk
383 * free memory
384 */
__mptcp_rmem(const struct sock * sk)385 static inline int __mptcp_rmem(const struct sock *sk)
386 {
387 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released);
388 }
389
mptcp_win_from_space(const struct sock * sk,int space)390 static inline int mptcp_win_from_space(const struct sock *sk, int space)
391 {
392 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space);
393 }
394
mptcp_space_from_win(const struct sock * sk,int win)395 static inline int mptcp_space_from_win(const struct sock *sk, int win)
396 {
397 return __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, win);
398 }
399
__mptcp_space(const struct sock * sk)400 static inline int __mptcp_space(const struct sock *sk)
401 {
402 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk));
403 }
404
mptcp_send_head(const struct sock * sk)405 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk)
406 {
407 const struct mptcp_sock *msk = mptcp_sk(sk);
408
409 return READ_ONCE(msk->first_pending);
410 }
411
mptcp_send_next(struct sock * sk)412 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk)
413 {
414 struct mptcp_sock *msk = mptcp_sk(sk);
415 struct mptcp_data_frag *cur;
416
417 cur = msk->first_pending;
418 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL :
419 list_next_entry(cur, list);
420 }
421
mptcp_pending_tail(const struct sock * sk)422 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
423 {
424 const struct mptcp_sock *msk = mptcp_sk(sk);
425
426 if (!msk->first_pending)
427 return NULL;
428
429 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue)))
430 return NULL;
431
432 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
433 }
434
mptcp_rtx_head(struct sock * sk)435 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk)
436 {
437 struct mptcp_sock *msk = mptcp_sk(sk);
438
439 if (msk->snd_una == msk->snd_nxt)
440 return NULL;
441
442 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list);
443 }
444
445 struct csum_pseudo_header {
446 __be64 data_seq;
447 __be32 subflow_seq;
448 __be16 data_len;
449 __sum16 csum;
450 };
451
452 struct mptcp_subflow_request_sock {
453 struct tcp_request_sock sk;
454 u16 mp_capable : 1,
455 mp_join : 1,
456 backup : 1,
457 request_bkup : 1,
458 csum_reqd : 1,
459 allow_join_id0 : 1;
460 u8 local_id;
461 u8 remote_id;
462 u64 local_key;
463 u64 idsn;
464 u32 token;
465 u32 ssn_offset;
466 u64 thmac;
467 u32 local_nonce;
468 u32 remote_nonce;
469 struct mptcp_sock *msk;
470 struct hlist_nulls_node token_node;
471 };
472
473 static inline struct mptcp_subflow_request_sock *
mptcp_subflow_rsk(const struct request_sock * rsk)474 mptcp_subflow_rsk(const struct request_sock *rsk)
475 {
476 return (struct mptcp_subflow_request_sock *)rsk;
477 }
478
479 struct mptcp_delegated_action {
480 struct napi_struct napi;
481 struct list_head head;
482 };
483
484 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
485
486 #define MPTCP_DELEGATE_SCHEDULED 0
487 #define MPTCP_DELEGATE_SEND 1
488 #define MPTCP_DELEGATE_ACK 2
489 #define MPTCP_DELEGATE_SNDBUF 3
490
491 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED))
492 /* MPTCP subflow context */
493 struct mptcp_subflow_context {
494 struct list_head node;/* conn_list of subflows */
495
496 struct_group(reset,
497
498 unsigned long avg_pacing_rate; /* protected by msk socket lock */
499 u64 local_key;
500 u64 remote_key;
501 u64 idsn;
502 u64 map_seq;
503 u32 snd_isn;
504 u32 token;
505 u32 rel_write_seq;
506 u32 map_subflow_seq;
507 u32 ssn_offset;
508 u32 map_data_len;
509 __wsum map_data_csum;
510 u32 map_csum_len;
511 u32 request_mptcp : 1, /* send MP_CAPABLE */
512 request_join : 1, /* send MP_JOIN */
513 request_bkup : 1,
514 mp_capable : 1, /* remote is MPTCP capable */
515 mp_join : 1, /* remote is JOINing */
516 fully_established : 1, /* path validated */
517 pm_notified : 1, /* PM hook called for established status */
518 conn_finished : 1,
519 map_valid : 1,
520 map_csum_reqd : 1,
521 map_data_fin : 1,
522 mpc_map : 1,
523 backup : 1,
524 send_mp_prio : 1,
525 send_mp_fail : 1,
526 send_fastclose : 1,
527 send_infinite_map : 1,
528 remote_key_valid : 1, /* received the peer key from */
529 disposable : 1, /* ctx can be free at ulp release time */
530 stale : 1, /* unable to snd/rcv data, do not use for xmit */
531 valid_csum_seen : 1, /* at least one csum validated */
532 is_mptfo : 1, /* subflow is doing TFO */
533 close_event_done : 1, /* has done the post-closed part */
534 mpc_drop : 1, /* the MPC option has been dropped in a rtx */
535 __unused : 8;
536 bool data_avail;
537 bool scheduled;
538 u32 remote_nonce;
539 u64 thmac;
540 u32 local_nonce;
541 u32 remote_token;
542 union {
543 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */
544 u64 iasn; /* initial ack sequence number, MPC subflows only */
545 };
546 s16 local_id; /* if negative not initialized yet */
547 u8 remote_id;
548 u8 reset_seen:1;
549 u8 reset_transient:1;
550 u8 reset_reason:4;
551 u8 stale_count;
552
553 u32 subflow_id;
554
555 long delegated_status;
556 unsigned long fail_tout;
557
558 );
559
560 struct list_head delegated_node; /* link into delegated_action, protected by local BH */
561
562 u32 setsockopt_seq;
563 u32 stale_rcv_tstamp;
564 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf,
565 * protected by the msk socket lock
566 */
567
568 struct sock *tcp_sock; /* tcp sk backpointer */
569 struct sock *conn; /* parent mptcp_sock */
570 const struct inet_connection_sock_af_ops *icsk_af_ops;
571 void (*tcp_state_change)(struct sock *sk);
572 void (*tcp_error_report)(struct sock *sk);
573
574 struct rcu_head rcu;
575 };
576
577 static inline struct mptcp_subflow_context *
mptcp_subflow_ctx(const struct sock * sk)578 mptcp_subflow_ctx(const struct sock *sk)
579 {
580 const struct inet_connection_sock *icsk = inet_csk(sk);
581
582 /* Use RCU on icsk_ulp_data only for sock diag code */
583 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data;
584 }
585
586 static inline struct sock *
mptcp_subflow_tcp_sock(const struct mptcp_subflow_context * subflow)587 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
588 {
589 return subflow->tcp_sock;
590 }
591
592 static inline void
mptcp_subflow_ctx_reset(struct mptcp_subflow_context * subflow)593 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow)
594 {
595 memset(&subflow->reset, 0, sizeof(subflow->reset));
596 subflow->request_mptcp = 1;
597 WRITE_ONCE(subflow->local_id, -1);
598 }
599
600 /* Convert reset reasons in MPTCP to enum sk_rst_reason type */
601 static inline enum sk_rst_reason
sk_rst_convert_mptcp_reason(u32 reason)602 sk_rst_convert_mptcp_reason(u32 reason)
603 {
604 switch (reason) {
605 case MPTCP_RST_EUNSPEC:
606 return SK_RST_REASON_MPTCP_RST_EUNSPEC;
607 case MPTCP_RST_EMPTCP:
608 return SK_RST_REASON_MPTCP_RST_EMPTCP;
609 case MPTCP_RST_ERESOURCE:
610 return SK_RST_REASON_MPTCP_RST_ERESOURCE;
611 case MPTCP_RST_EPROHIBIT:
612 return SK_RST_REASON_MPTCP_RST_EPROHIBIT;
613 case MPTCP_RST_EWQ2BIG:
614 return SK_RST_REASON_MPTCP_RST_EWQ2BIG;
615 case MPTCP_RST_EBADPERF:
616 return SK_RST_REASON_MPTCP_RST_EBADPERF;
617 case MPTCP_RST_EMIDDLEBOX:
618 return SK_RST_REASON_MPTCP_RST_EMIDDLEBOX;
619 default:
620 /* It should not happen, or else errors may occur
621 * in MPTCP layer
622 */
623 return SK_RST_REASON_ERROR;
624 }
625 }
626
627 static inline void
mptcp_send_active_reset_reason(struct sock * sk)628 mptcp_send_active_reset_reason(struct sock *sk)
629 {
630 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
631 enum sk_rst_reason reason;
632
633 reason = sk_rst_convert_mptcp_reason(subflow->reset_reason);
634 tcp_send_active_reset(sk, GFP_ATOMIC, reason);
635 }
636
637 static inline u64
mptcp_subflow_get_map_offset(const struct mptcp_subflow_context * subflow)638 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow)
639 {
640 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq -
641 subflow->ssn_offset -
642 subflow->map_subflow_seq;
643 }
644
645 static inline u64
mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context * subflow)646 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow)
647 {
648 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow);
649 }
650
651 void mptcp_subflow_process_delegated(struct sock *ssk, long actions);
652
mptcp_subflow_delegate(struct mptcp_subflow_context * subflow,int action)653 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action)
654 {
655 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action);
656 struct mptcp_delegated_action *delegated;
657 bool schedule;
658
659 /* the caller held the subflow bh socket lock */
660 lockdep_assert_in_softirq();
661
662 /* The implied barrier pairs with tcp_release_cb_override()
663 * mptcp_napi_poll(), and ensures the below list check sees list
664 * updates done prior to delegated status bits changes
665 */
666 old = set_mask_bits(&subflow->delegated_status, 0, set_bits);
667 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) {
668 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node)))
669 return;
670
671 delegated = this_cpu_ptr(&mptcp_delegated_actions);
672 schedule = list_empty(&delegated->head);
673 list_add_tail(&subflow->delegated_node, &delegated->head);
674 sock_hold(mptcp_subflow_tcp_sock(subflow));
675 if (schedule)
676 napi_schedule(&delegated->napi);
677 }
678 }
679
680 static inline struct mptcp_subflow_context *
mptcp_subflow_delegated_next(struct mptcp_delegated_action * delegated)681 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated)
682 {
683 struct mptcp_subflow_context *ret;
684
685 if (list_empty(&delegated->head))
686 return NULL;
687
688 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node);
689 list_del_init(&ret->delegated_node);
690 return ret;
691 }
692
693 int mptcp_is_enabled(const struct net *net);
694 unsigned int mptcp_get_add_addr_timeout(const struct net *net);
695 int mptcp_is_checksum_enabled(const struct net *net);
696 int mptcp_allow_join_id0(const struct net *net);
697 unsigned int mptcp_stale_loss_cnt(const struct net *net);
698 unsigned int mptcp_close_timeout(const struct sock *sk);
699 int mptcp_get_pm_type(const struct net *net);
700 const char *mptcp_get_scheduler(const struct net *net);
701
702 void mptcp_active_disable(struct sock *sk);
703 bool mptcp_active_should_disable(struct sock *ssk);
704 void mptcp_active_enable(struct sock *sk);
705
706 void mptcp_get_available_schedulers(char *buf, size_t maxlen);
707 void __mptcp_subflow_fully_established(struct mptcp_sock *msk,
708 struct mptcp_subflow_context *subflow,
709 const struct mptcp_options_received *mp_opt);
710 bool __mptcp_retransmit_pending_data(struct sock *sk);
711 void mptcp_check_and_set_pending(struct sock *sk);
712 void __mptcp_push_pending(struct sock *sk, unsigned int flags);
713 bool mptcp_subflow_data_available(struct sock *sk);
714 void __init mptcp_subflow_init(void);
715 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how);
716 void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
717 struct mptcp_subflow_context *subflow);
718 void __mptcp_subflow_send_ack(struct sock *ssk);
719 void mptcp_subflow_reset(struct sock *ssk);
720 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk);
721 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
722 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk);
723 bool __mptcp_close(struct sock *sk, long timeout);
724 void mptcp_cancel_work(struct sock *sk);
725 void __mptcp_unaccepted_force_close(struct sock *sk);
726 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk);
727 void mptcp_set_state(struct sock *sk, int state);
728
729 bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
730 const struct mptcp_addr_info *b, bool use_port);
731 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr);
732
733 /* called with sk socket lock held */
734 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_pm_local *local,
735 const struct mptcp_addr_info *remote);
736 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family,
737 struct socket **new_sock);
738 void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
739 struct sockaddr_storage *addr,
740 unsigned short family);
741 struct mptcp_sched_ops *mptcp_sched_find(const char *name);
742 int mptcp_register_scheduler(struct mptcp_sched_ops *sched);
743 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched);
744 void mptcp_sched_init(void);
745 int mptcp_init_sched(struct mptcp_sock *msk,
746 struct mptcp_sched_ops *sched);
747 void mptcp_release_sched(struct mptcp_sock *msk);
748 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
749 bool scheduled);
750 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk);
751 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk);
752 int mptcp_sched_get_send(struct mptcp_sock *msk);
753 int mptcp_sched_get_retrans(struct mptcp_sock *msk);
754
mptcp_data_avail(const struct mptcp_sock * msk)755 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk)
756 {
757 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed);
758 }
759
mptcp_epollin_ready(const struct sock * sk)760 static inline bool mptcp_epollin_ready(const struct sock *sk)
761 {
762 /* mptcp doesn't have to deal with small skbs in the receive queue,
763 * at it can always coalesce them
764 */
765 return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) ||
766 (mem_cgroup_sockets_enabled && sk->sk_memcg &&
767 mem_cgroup_under_socket_pressure(sk->sk_memcg)) ||
768 READ_ONCE(tcp_memory_pressure);
769 }
770
771 int mptcp_set_rcvlowat(struct sock *sk, int val);
772
__tcp_can_send(const struct sock * ssk)773 static inline bool __tcp_can_send(const struct sock *ssk)
774 {
775 /* only send if our side has not closed yet */
776 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT));
777 }
778
__mptcp_subflow_active(struct mptcp_subflow_context * subflow)779 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow)
780 {
781 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */
782 if (subflow->request_join && !subflow->fully_established)
783 return false;
784
785 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow));
786 }
787
788 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow);
789
790 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow);
791
792 void mptcp_subflow_drop_ctx(struct sock *ssk);
793
mptcp_subflow_tcp_fallback(struct sock * sk,struct mptcp_subflow_context * ctx)794 static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
795 struct mptcp_subflow_context *ctx)
796 {
797 sk->sk_data_ready = sock_def_readable;
798 sk->sk_state_change = ctx->tcp_state_change;
799 sk->sk_write_space = sk_stream_write_space;
800 sk->sk_error_report = ctx->tcp_error_report;
801
802 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
803 }
804
805 void __init mptcp_proto_init(void);
806 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
807 int __init mptcp_proto_v6_init(void);
808 #endif
809
810 struct sock *mptcp_sk_clone_init(const struct sock *sk,
811 const struct mptcp_options_received *mp_opt,
812 struct sock *ssk,
813 struct request_sock *req);
814 void mptcp_get_options(const struct sk_buff *skb,
815 struct mptcp_options_received *mp_opt);
816
817 void mptcp_finish_connect(struct sock *sk);
818 void __mptcp_sync_state(struct sock *sk, int state);
819 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout);
820
mptcp_stop_tout_timer(struct sock * sk)821 static inline void mptcp_stop_tout_timer(struct sock *sk)
822 {
823 if (!inet_csk(sk)->icsk_mtup.probe_timestamp)
824 return;
825
826 sk_stop_timer(sk, &sk->sk_timer);
827 inet_csk(sk)->icsk_mtup.probe_timestamp = 0;
828 }
829
mptcp_set_close_tout(struct sock * sk,unsigned long tout)830 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout)
831 {
832 /* avoid 0 timestamp, as that means no close timeout */
833 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1;
834 }
835
mptcp_start_tout_timer(struct sock * sk)836 static inline void mptcp_start_tout_timer(struct sock *sk)
837 {
838 mptcp_set_close_tout(sk, tcp_jiffies32);
839 mptcp_reset_tout_timer(mptcp_sk(sk), 0);
840 }
841
mptcp_is_fully_established(struct sock * sk)842 static inline bool mptcp_is_fully_established(struct sock *sk)
843 {
844 return inet_sk_state_load(sk) == TCP_ESTABLISHED &&
845 READ_ONCE(mptcp_sk(sk)->fully_established);
846 }
847
848 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk);
849 void mptcp_data_ready(struct sock *sk, struct sock *ssk);
850 bool mptcp_finish_join(struct sock *sk);
851 bool mptcp_schedule_work(struct sock *sk);
852 int mptcp_setsockopt(struct sock *sk, int level, int optname,
853 sockptr_t optval, unsigned int optlen);
854 int mptcp_getsockopt(struct sock *sk, int level, int optname,
855 char __user *optval, int __user *option);
856
857 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq);
mptcp_expand_seq(u64 old_seq,u64 cur_seq,bool use_64bit)858 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit)
859 {
860 if (use_64bit)
861 return cur_seq;
862
863 return __mptcp_expand_seq(old_seq, cur_seq);
864 }
865 void __mptcp_check_push(struct sock *sk, struct sock *ssk);
866 void __mptcp_data_acked(struct sock *sk);
867 void __mptcp_error_report(struct sock *sk);
868 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)869 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk)
870 {
871 return READ_ONCE(msk->snd_data_fin_enable) &&
872 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt);
873 }
874
mptcp_notsent_lowat(const struct sock * sk)875 static inline u32 mptcp_notsent_lowat(const struct sock *sk)
876 {
877 struct net *net = sock_net(sk);
878 u32 val;
879
880 val = READ_ONCE(mptcp_sk(sk)->notsent_lowat);
881 return val ?: READ_ONCE(net->ipv4.sysctl_tcp_notsent_lowat);
882 }
883
mptcp_stream_memory_free(const struct sock * sk,int wake)884 static inline bool mptcp_stream_memory_free(const struct sock *sk, int wake)
885 {
886 const struct mptcp_sock *msk = mptcp_sk(sk);
887 u32 notsent_bytes;
888
889 notsent_bytes = READ_ONCE(msk->write_seq) - READ_ONCE(msk->snd_nxt);
890 return (notsent_bytes << wake) < mptcp_notsent_lowat(sk);
891 }
892
__mptcp_stream_is_writeable(const struct sock * sk,int wake)893 static inline bool __mptcp_stream_is_writeable(const struct sock *sk, int wake)
894 {
895 return mptcp_stream_memory_free(sk, wake) &&
896 __sk_stream_is_writeable(sk, wake);
897 }
898
mptcp_write_space(struct sock * sk)899 static inline void mptcp_write_space(struct sock *sk)
900 {
901 /* pairs with memory barrier in mptcp_poll */
902 smp_mb();
903 if (mptcp_stream_memory_free(sk, 1))
904 sk_stream_write_space(sk);
905 }
906
__mptcp_sync_sndbuf(struct sock * sk)907 static inline void __mptcp_sync_sndbuf(struct sock *sk)
908 {
909 struct mptcp_subflow_context *subflow;
910 int ssk_sndbuf, new_sndbuf;
911
912 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
913 return;
914
915 new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]);
916 mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
917 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf);
918
919 subflow->cached_sndbuf = ssk_sndbuf;
920 new_sndbuf += ssk_sndbuf;
921 }
922
923 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */
924 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf);
925 mptcp_write_space(sk);
926 }
927
928 /* The called held both the msk socket and the subflow socket locks,
929 * possibly under BH
930 */
__mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)931 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
932 {
933 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
934
935 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf)
936 __mptcp_sync_sndbuf(sk);
937 }
938
939 /* the caller held only the subflow socket lock, either in process or
940 * BH context. Additionally this can be called under the msk data lock,
941 * so we can't acquire such lock here: let the delegate action acquires
942 * the needed locks in suitable order.
943 */
mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)944 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
945 {
946 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
947
948 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf))
949 return;
950
951 local_bh_disable();
952 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF);
953 local_bh_enable();
954 }
955
956 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags);
957
958 #define MPTCP_TOKEN_MAX_RETRIES 4
959
960 void __init mptcp_token_init(void);
mptcp_token_init_request(struct request_sock * req)961 static inline void mptcp_token_init_request(struct request_sock *req)
962 {
963 mptcp_subflow_rsk(req)->token_node.pprev = NULL;
964 }
965
966 int mptcp_token_new_request(struct request_sock *req);
967 void mptcp_token_destroy_request(struct request_sock *req);
968 int mptcp_token_new_connect(struct sock *ssk);
969 void mptcp_token_accept(struct mptcp_subflow_request_sock *r,
970 struct mptcp_sock *msk);
971 bool mptcp_token_exists(u32 token);
972 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token);
973 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot,
974 long *s_num);
975 void mptcp_token_destroy(struct mptcp_sock *msk);
976
977 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
978
979 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac);
980 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum);
981
982 void __init mptcp_pm_init(void);
983 void mptcp_pm_data_init(struct mptcp_sock *msk);
984 void mptcp_pm_data_reset(struct mptcp_sock *msk);
985 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
986 struct mptcp_addr_info *addr);
987 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
988 bool require_family,
989 struct mptcp_pm_addr_entry *entry);
990 bool mptcp_pm_addr_families_match(const struct sock *sk,
991 const struct mptcp_addr_info *loc,
992 const struct mptcp_addr_info *rem);
993 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
994 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
995 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side);
996 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk);
997 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk);
998 void mptcp_pm_connection_closed(struct mptcp_sock *msk);
999 void mptcp_pm_subflow_established(struct mptcp_sock *msk);
1000 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk);
1001 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk,
1002 const struct mptcp_subflow_context *subflow);
1003 void mptcp_pm_add_addr_received(const struct sock *ssk,
1004 const struct mptcp_addr_info *addr);
1005 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
1006 const struct mptcp_addr_info *addr);
1007 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk);
1008 bool mptcp_pm_nl_is_init_remote_addr(struct mptcp_sock *msk,
1009 const struct mptcp_addr_info *remote);
1010 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk);
1011 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
1012 const struct mptcp_rm_list *rm_list);
1013 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
1014 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
1015 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
1016 struct mptcp_addr_info *addr,
1017 struct mptcp_addr_info *rem,
1018 u8 bkup);
1019 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
1020 const struct mptcp_addr_info *addr);
1021 void mptcp_pm_free_anno_list(struct mptcp_sock *msk);
1022 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
1023 struct mptcp_pm_add_entry *
1024 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
1025 const struct mptcp_addr_info *addr, bool check_id);
1026 struct mptcp_pm_add_entry *
1027 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
1028 const struct mptcp_addr_info *addr);
1029 int mptcp_pm_set_flags(struct sk_buff *skb, struct genl_info *info);
1030 int mptcp_pm_nl_set_flags(struct sk_buff *skb, struct genl_info *info);
1031 int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info);
1032 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
1033 const struct mptcp_addr_info *addr,
1034 bool echo);
1035 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
1036 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list);
1037
1038 void mptcp_free_local_addr_list(struct mptcp_sock *msk);
1039
1040 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
1041 const struct sock *ssk, gfp_t gfp);
1042 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info);
1043 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
1044 void mptcp_event_pm_listener(const struct sock *ssk,
1045 enum mptcp_event_type event);
1046 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk);
1047
1048 void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
1049 const struct mptcp_options_received *mp_opt);
1050 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow,
1051 struct request_sock *req);
1052 int mptcp_nl_fill_addr(struct sk_buff *skb,
1053 struct mptcp_pm_addr_entry *entry);
1054
mptcp_pm_should_add_signal(struct mptcp_sock * msk)1055 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk)
1056 {
1057 return READ_ONCE(msk->pm.addr_signal) &
1058 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
1059 }
1060
mptcp_pm_should_add_signal_addr(struct mptcp_sock * msk)1061 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk)
1062 {
1063 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL);
1064 }
1065
mptcp_pm_should_add_signal_echo(struct mptcp_sock * msk)1066 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk)
1067 {
1068 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO);
1069 }
1070
mptcp_pm_should_rm_signal(struct mptcp_sock * msk)1071 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)
1072 {
1073 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL);
1074 }
1075
mptcp_pm_is_userspace(const struct mptcp_sock * msk)1076 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk)
1077 {
1078 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE;
1079 }
1080
mptcp_pm_is_kernel(const struct mptcp_sock * msk)1081 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk)
1082 {
1083 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL;
1084 }
1085
mptcp_add_addr_len(int family,bool echo,bool port)1086 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port)
1087 {
1088 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
1089
1090 if (family == AF_INET6)
1091 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
1092 if (!echo)
1093 len += MPTCPOPT_THMAC_LEN;
1094 /* account for 2 trailing 'nop' options */
1095 if (port)
1096 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
1097
1098 return len;
1099 }
1100
mptcp_rm_addr_len(const struct mptcp_rm_list * rm_list)1101 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
1102 {
1103 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX)
1104 return -EINVAL;
1105
1106 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
1107 }
1108
1109 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
1110 unsigned int opt_size, unsigned int remaining,
1111 struct mptcp_addr_info *addr, bool *echo,
1112 bool *drop_other_suboptions);
1113 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
1114 struct mptcp_rm_list *rm_list);
1115 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
1116 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1117 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1118 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc);
1119 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1120 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
1121 int mptcp_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb);
1122 int mptcp_pm_nl_dump_addr(struct sk_buff *msg,
1123 struct netlink_callback *cb);
1124 int mptcp_userspace_pm_dump_addr(struct sk_buff *msg,
1125 struct netlink_callback *cb);
1126 int mptcp_pm_get_addr(struct sk_buff *skb, struct genl_info *info);
1127 int mptcp_pm_nl_get_addr(struct sk_buff *skb, struct genl_info *info);
1128 int mptcp_userspace_pm_get_addr(struct sk_buff *skb,
1129 struct genl_info *info);
1130
subflow_get_local_id(const struct mptcp_subflow_context * subflow)1131 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow)
1132 {
1133 int local_id = READ_ONCE(subflow->local_id);
1134
1135 if (local_id < 0)
1136 return 0;
1137 return local_id;
1138 }
1139
1140 void __init mptcp_pm_nl_init(void);
1141 void mptcp_pm_nl_work(struct mptcp_sock *msk);
1142 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk);
1143 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk);
1144 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk);
1145 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk);
1146
1147 /* called under PM lock */
__mptcp_pm_close_subflow(struct mptcp_sock * msk)1148 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk)
1149 {
1150 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk))
1151 WRITE_ONCE(msk->pm.accept_subflow, true);
1152 }
1153
mptcp_pm_close_subflow(struct mptcp_sock * msk)1154 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk)
1155 {
1156 spin_lock_bh(&msk->pm.lock);
1157 __mptcp_pm_close_subflow(msk);
1158 spin_unlock_bh(&msk->pm.lock);
1159 }
1160
1161 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk);
1162
mptcp_get_ext(const struct sk_buff * skb)1163 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb)
1164 {
1165 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
1166 }
1167
1168 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);
1169
__mptcp_check_fallback(const struct mptcp_sock * msk)1170 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)
1171 {
1172 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags);
1173 }
1174
mptcp_check_fallback(const struct sock * sk)1175 static inline bool mptcp_check_fallback(const struct sock *sk)
1176 {
1177 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1178 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
1179
1180 return __mptcp_check_fallback(msk);
1181 }
1182
__mptcp_do_fallback(struct mptcp_sock * msk)1183 static inline void __mptcp_do_fallback(struct mptcp_sock *msk)
1184 {
1185 if (__mptcp_check_fallback(msk)) {
1186 pr_debug("TCP fallback already done (msk=%p)\n", msk);
1187 return;
1188 }
1189 set_bit(MPTCP_FALLBACK_DONE, &msk->flags);
1190 }
1191
__mptcp_has_initial_subflow(const struct mptcp_sock * msk)1192 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk)
1193 {
1194 struct sock *ssk = READ_ONCE(msk->first);
1195
1196 return ssk && ((1 << inet_sk_state_load(ssk)) &
1197 (TCPF_ESTABLISHED | TCPF_SYN_SENT |
1198 TCPF_SYN_RECV | TCPF_LISTEN));
1199 }
1200
mptcp_do_fallback(struct sock * ssk)1201 static inline void mptcp_do_fallback(struct sock *ssk)
1202 {
1203 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1204 struct sock *sk = subflow->conn;
1205 struct mptcp_sock *msk;
1206
1207 msk = mptcp_sk(sk);
1208 __mptcp_do_fallback(msk);
1209 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) {
1210 gfp_t saved_allocation = ssk->sk_allocation;
1211
1212 /* we are in a atomic (BH) scope, override ssk default for data
1213 * fin allocation
1214 */
1215 ssk->sk_allocation = GFP_ATOMIC;
1216 ssk->sk_shutdown |= SEND_SHUTDOWN;
1217 tcp_shutdown(ssk, SEND_SHUTDOWN);
1218 ssk->sk_allocation = saved_allocation;
1219 }
1220 }
1221
1222 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)\n", __func__, a)
1223
mptcp_subflow_early_fallback(struct mptcp_sock * msk,struct mptcp_subflow_context * subflow)1224 static inline void mptcp_subflow_early_fallback(struct mptcp_sock *msk,
1225 struct mptcp_subflow_context *subflow)
1226 {
1227 pr_fallback(msk);
1228 subflow->request_mptcp = 0;
1229 __mptcp_do_fallback(msk);
1230 }
1231
mptcp_check_infinite_map(struct sk_buff * skb)1232 static inline bool mptcp_check_infinite_map(struct sk_buff *skb)
1233 {
1234 struct mptcp_ext *mpext;
1235
1236 mpext = skb ? mptcp_get_ext(skb) : NULL;
1237 if (mpext && mpext->infinite_map)
1238 return true;
1239
1240 return false;
1241 }
1242
is_active_ssk(struct mptcp_subflow_context * subflow)1243 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow)
1244 {
1245 return (subflow->request_mptcp || subflow->request_join);
1246 }
1247
subflow_simultaneous_connect(struct sock * sk)1248 static inline bool subflow_simultaneous_connect(struct sock *sk)
1249 {
1250 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
1251
1252 return (1 << sk->sk_state) &
1253 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) &&
1254 is_active_ssk(subflow) &&
1255 !subflow->conn_finished;
1256 }
1257
1258 #ifdef CONFIG_SYN_COOKIES
1259 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1260 struct sk_buff *skb);
1261 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1262 struct sk_buff *skb);
1263 void __init mptcp_join_cookie_init(void);
1264 #else
1265 static inline void
subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1266 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
1267 struct sk_buff *skb) {}
1268 static inline bool
mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)1269 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
1270 struct sk_buff *skb)
1271 {
1272 return false;
1273 }
1274
mptcp_join_cookie_init(void)1275 static inline void mptcp_join_cookie_init(void) {}
1276 #endif
1277
1278 #endif /* __MPTCP_PROTOCOL_H */
1279