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
15 #define MPTCP_SUPPORTED_VERSION 1
16
17 /* MPTCP option bits */
18 #define OPTION_MPTCP_MPC_SYN BIT(0)
19 #define OPTION_MPTCP_MPC_SYNACK BIT(1)
20 #define OPTION_MPTCP_MPC_ACK BIT(2)
21 #define OPTION_MPTCP_MPJ_SYN BIT(3)
22 #define OPTION_MPTCP_MPJ_SYNACK BIT(4)
23 #define OPTION_MPTCP_MPJ_ACK BIT(5)
24 #define OPTION_MPTCP_ADD_ADDR BIT(6)
25 #define OPTION_MPTCP_RM_ADDR BIT(7)
26 #define OPTION_MPTCP_FASTCLOSE BIT(8)
27 #define OPTION_MPTCP_PRIO BIT(9)
28 #define OPTION_MPTCP_RST BIT(10)
29 #define OPTION_MPTCP_DSS BIT(11)
30 #define OPTION_MPTCP_FAIL BIT(12)
31
32 #define OPTION_MPTCP_CSUMREQD BIT(13)
33
34 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \
35 OPTION_MPTCP_MPC_ACK)
36 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \
37 OPTION_MPTCP_MPJ_ACK)
38
39 /* MPTCP option subtypes */
40 #define MPTCPOPT_MP_CAPABLE 0
41 #define MPTCPOPT_MP_JOIN 1
42 #define MPTCPOPT_DSS 2
43 #define MPTCPOPT_ADD_ADDR 3
44 #define MPTCPOPT_RM_ADDR 4
45 #define MPTCPOPT_MP_PRIO 5
46 #define MPTCPOPT_MP_FAIL 6
47 #define MPTCPOPT_MP_FASTCLOSE 7
48 #define MPTCPOPT_RST 8
49
50 /* MPTCP suboption lengths */
51 #define TCPOLEN_MPTCP_MPC_SYN 4
52 #define TCPOLEN_MPTCP_MPC_SYNACK 12
53 #define TCPOLEN_MPTCP_MPC_ACK 20
54 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22
55 #define TCPOLEN_MPTCP_MPJ_SYN 12
56 #define TCPOLEN_MPTCP_MPJ_SYNACK 16
57 #define TCPOLEN_MPTCP_MPJ_ACK 24
58 #define TCPOLEN_MPTCP_DSS_BASE 4
59 #define TCPOLEN_MPTCP_DSS_ACK32 4
60 #define TCPOLEN_MPTCP_DSS_ACK64 8
61 #define TCPOLEN_MPTCP_DSS_MAP32 10
62 #define TCPOLEN_MPTCP_DSS_MAP64 14
63 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2
64 #define TCPOLEN_MPTCP_ADD_ADDR 16
65 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18
66 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8
67 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10
68 #define TCPOLEN_MPTCP_ADD_ADDR6 28
69 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30
70 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20
71 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22
72 #define TCPOLEN_MPTCP_PORT_LEN 2
73 #define TCPOLEN_MPTCP_PORT_ALIGN 2
74 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3
75 #define TCPOLEN_MPTCP_PRIO 3
76 #define TCPOLEN_MPTCP_PRIO_ALIGN 4
77 #define TCPOLEN_MPTCP_FASTCLOSE 12
78 #define TCPOLEN_MPTCP_RST 4
79 #define TCPOLEN_MPTCP_FAIL 12
80
81 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA)
82
83 /* MPTCP MP_JOIN flags */
84 #define MPTCPOPT_BACKUP BIT(0)
85 #define MPTCPOPT_HMAC_LEN 20
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 flags */
114 #define MPTCP_DATA_READY 0
115 #define MPTCP_NOSPACE 1
116 #define MPTCP_WORK_RTX 2
117 #define MPTCP_WORK_EOF 3
118 #define MPTCP_FALLBACK_DONE 4
119 #define MPTCP_WORK_CLOSE_SUBFLOW 5
120 #define MPTCP_PUSH_PENDING 6
121 #define MPTCP_CLEAN_UNA 7
122 #define MPTCP_ERROR_REPORT 8
123 #define MPTCP_RETRANSMIT 9
124 #define MPTCP_WORK_SYNC_SETSOCKOPT 10
125 #define MPTCP_CONNECTED 11
126
before64(__u64 seq1,__u64 seq2)127 static inline bool before64(__u64 seq1, __u64 seq2)
128 {
129 return (__s64)(seq1 - seq2) < 0;
130 }
131
132 #define after64(seq2, seq1) before64(seq1, seq2)
133
134 struct mptcp_options_received {
135 u64 sndr_key;
136 u64 rcvr_key;
137 u64 data_ack;
138 u64 data_seq;
139 u32 subflow_seq;
140 u16 data_len;
141 __sum16 csum;
142 u16 suboptions;
143 u32 token;
144 u32 nonce;
145 u16 use_map:1,
146 dsn64:1,
147 data_fin:1,
148 use_ack:1,
149 ack64:1,
150 mpc_map:1,
151 reset_reason:4,
152 reset_transient:1,
153 echo:1,
154 backup:1,
155 deny_join_id0:1,
156 __unused:2;
157 u8 join_id;
158 u64 thmac;
159 u8 hmac[MPTCPOPT_HMAC_LEN];
160 struct mptcp_addr_info addr;
161 struct mptcp_rm_list rm_list;
162 u64 ahmac;
163 u64 fail_seq;
164 };
165
mptcp_option(u8 subopt,u8 len,u8 nib,u8 field)166 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field)
167 {
168 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) |
169 ((nib & 0xF) << 8) | field);
170 }
171
172 enum mptcp_pm_status {
173 MPTCP_PM_ADD_ADDR_RECEIVED,
174 MPTCP_PM_ADD_ADDR_SEND_ACK,
175 MPTCP_PM_RM_ADDR_RECEIVED,
176 MPTCP_PM_ESTABLISHED,
177 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */
178 MPTCP_PM_SUBFLOW_ESTABLISHED,
179 };
180
181 enum mptcp_addr_signal_status {
182 MPTCP_ADD_ADDR_SIGNAL,
183 MPTCP_ADD_ADDR_ECHO,
184 MPTCP_RM_ADDR_SIGNAL,
185 };
186
187 struct mptcp_pm_data {
188 struct mptcp_addr_info local;
189 struct mptcp_addr_info remote;
190 struct list_head anno_list;
191
192 spinlock_t lock; /*protects the whole PM data */
193
194 u8 addr_signal;
195 bool server_side;
196 bool work_pending;
197 bool accept_addr;
198 bool accept_subflow;
199 bool remote_deny_join_id0;
200 u8 add_addr_signaled;
201 u8 add_addr_accepted;
202 u8 local_addr_used;
203 u8 subflows;
204 u8 status;
205 struct mptcp_rm_list rm_list_tx;
206 struct mptcp_rm_list rm_list_rx;
207 };
208
209 struct mptcp_data_frag {
210 struct list_head list;
211 u64 data_seq;
212 u16 data_len;
213 u16 offset;
214 u16 overhead;
215 u16 already_sent;
216 struct page *page;
217 };
218
219 /* MPTCP connection sock */
220 struct mptcp_sock {
221 /* inet_connection_sock must be the first member */
222 struct inet_connection_sock sk;
223 u64 local_key;
224 u64 remote_key;
225 u64 write_seq;
226 u64 snd_nxt;
227 u64 ack_seq;
228 u64 rcv_wnd_sent;
229 u64 rcv_data_fin_seq;
230 int rmem_fwd_alloc;
231 struct sock *last_snd;
232 int snd_burst;
233 int old_wspace;
234 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq;
235 * recovery related fields are under data_lock
236 * protection
237 */
238 u64 snd_una;
239 u64 wnd_end;
240 unsigned long timer_ival;
241 u32 token;
242 int rmem_released;
243 unsigned long flags;
244 bool recovery; /* closing subflow write queue reinjected */
245 bool can_ack;
246 bool fully_established;
247 bool rcv_data_fin;
248 bool snd_data_fin_enable;
249 bool rcv_fastclose;
250 bool use_64bit_ack; /* Set when we received a 64-bit DSN */
251 bool csum_enabled;
252 spinlock_t join_list_lock;
253 struct work_struct work;
254 struct sk_buff *ooo_last_skb;
255 struct rb_root out_of_order_queue;
256 struct sk_buff_head receive_queue;
257 struct list_head conn_list;
258 struct list_head rtx_queue;
259 struct mptcp_data_frag *first_pending;
260 struct list_head join_list;
261 struct socket *subflow; /* outgoing connect/listener/!mp_capable */
262 struct sock *first;
263 struct mptcp_pm_data pm;
264 struct {
265 u32 space; /* bytes copied in last measurement window */
266 u32 copied; /* bytes copied in this measurement window */
267 u64 time; /* start time of measurement window */
268 u64 rtt_us; /* last maximum rtt of subflows */
269 } rcvq_space;
270
271 u32 setsockopt_seq;
272 char ca_name[TCP_CA_NAME_MAX];
273 };
274
275 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock)
276 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock)
277
278 #define mptcp_for_each_subflow(__msk, __subflow) \
279 list_for_each_entry(__subflow, &((__msk)->conn_list), node)
280
msk_owned_by_me(const struct mptcp_sock * msk)281 static inline void msk_owned_by_me(const struct mptcp_sock *msk)
282 {
283 sock_owned_by_me((const struct sock *)msk);
284 }
285
mptcp_sk(const struct sock * sk)286 static inline struct mptcp_sock *mptcp_sk(const struct sock *sk)
287 {
288 return (struct mptcp_sock *)sk;
289 }
290
291 /* the msk socket don't use the backlog, also account for the bulk
292 * free memory
293 */
__mptcp_rmem(const struct sock * sk)294 static inline int __mptcp_rmem(const struct sock *sk)
295 {
296 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released);
297 }
298
__mptcp_space(const struct sock * sk)299 static inline int __mptcp_space(const struct sock *sk)
300 {
301 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk));
302 }
303
mptcp_send_head(const struct sock * sk)304 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk)
305 {
306 const struct mptcp_sock *msk = mptcp_sk(sk);
307
308 return READ_ONCE(msk->first_pending);
309 }
310
mptcp_send_next(struct sock * sk)311 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk)
312 {
313 struct mptcp_sock *msk = mptcp_sk(sk);
314 struct mptcp_data_frag *cur;
315
316 cur = msk->first_pending;
317 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL :
318 list_next_entry(cur, list);
319 }
320
mptcp_pending_tail(const struct sock * sk)321 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk)
322 {
323 struct mptcp_sock *msk = mptcp_sk(sk);
324
325 if (!msk->first_pending)
326 return NULL;
327
328 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue)))
329 return NULL;
330
331 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list);
332 }
333
mptcp_rtx_head(const struct sock * sk)334 static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk)
335 {
336 struct mptcp_sock *msk = mptcp_sk(sk);
337
338 if (msk->snd_una == READ_ONCE(msk->snd_nxt))
339 return NULL;
340
341 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list);
342 }
343
344 struct csum_pseudo_header {
345 __be64 data_seq;
346 __be32 subflow_seq;
347 __be16 data_len;
348 __sum16 csum;
349 };
350
351 struct mptcp_subflow_request_sock {
352 struct tcp_request_sock sk;
353 u16 mp_capable : 1,
354 mp_join : 1,
355 backup : 1,
356 csum_reqd : 1,
357 allow_join_id0 : 1;
358 u8 local_id;
359 u8 remote_id;
360 u64 local_key;
361 u64 idsn;
362 u32 token;
363 u32 ssn_offset;
364 u64 thmac;
365 u32 local_nonce;
366 u32 remote_nonce;
367 struct mptcp_sock *msk;
368 struct hlist_nulls_node token_node;
369 };
370
371 static inline struct mptcp_subflow_request_sock *
mptcp_subflow_rsk(const struct request_sock * rsk)372 mptcp_subflow_rsk(const struct request_sock *rsk)
373 {
374 return (struct mptcp_subflow_request_sock *)rsk;
375 }
376
377 enum mptcp_data_avail {
378 MPTCP_SUBFLOW_NODATA,
379 MPTCP_SUBFLOW_DATA_AVAIL,
380 };
381
382 struct mptcp_delegated_action {
383 struct napi_struct napi;
384 struct list_head head;
385 };
386
387 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions);
388
389 #define MPTCP_DELEGATE_SEND 0
390 #define MPTCP_DELEGATE_ACK 1
391
392 /* MPTCP subflow context */
393 struct mptcp_subflow_context {
394 struct list_head node;/* conn_list of subflows */
395 u64 local_key;
396 u64 remote_key;
397 u64 idsn;
398 u64 map_seq;
399 u32 snd_isn;
400 u32 token;
401 u32 rel_write_seq;
402 u32 map_subflow_seq;
403 u32 ssn_offset;
404 u32 map_data_len;
405 __wsum map_data_csum;
406 u32 map_csum_len;
407 u32 request_mptcp : 1, /* send MP_CAPABLE */
408 request_join : 1, /* send MP_JOIN */
409 request_bkup : 1,
410 mp_capable : 1, /* remote is MPTCP capable */
411 mp_join : 1, /* remote is JOINing */
412 fully_established : 1, /* path validated */
413 pm_notified : 1, /* PM hook called for established status */
414 conn_finished : 1,
415 map_valid : 1,
416 map_csum_reqd : 1,
417 map_data_fin : 1,
418 mpc_map : 1,
419 backup : 1,
420 send_mp_prio : 1,
421 send_mp_fail : 1,
422 rx_eof : 1,
423 can_ack : 1, /* only after processing the remote a key */
424 disposable : 1, /* ctx can be free at ulp release time */
425 stale : 1; /* unable to snd/rcv data, do not use for xmit */
426 enum mptcp_data_avail data_avail;
427 u32 remote_nonce;
428 u64 thmac;
429 u32 local_nonce;
430 u32 remote_token;
431 u8 hmac[MPTCPOPT_HMAC_LEN];
432 u8 local_id;
433 u8 remote_id;
434 u8 reset_seen:1;
435 u8 reset_transient:1;
436 u8 reset_reason:4;
437 u8 stale_count;
438
439 long delegated_status;
440 struct list_head delegated_node; /* link into delegated_action, protected by local BH */
441
442 u32 setsockopt_seq;
443 u32 stale_rcv_tstamp;
444
445 struct sock *tcp_sock; /* tcp sk backpointer */
446 struct sock *conn; /* parent mptcp_sock */
447 const struct inet_connection_sock_af_ops *icsk_af_ops;
448 void (*tcp_data_ready)(struct sock *sk);
449 void (*tcp_state_change)(struct sock *sk);
450 void (*tcp_write_space)(struct sock *sk);
451 void (*tcp_error_report)(struct sock *sk);
452
453 struct rcu_head rcu;
454 };
455
456 static inline struct mptcp_subflow_context *
mptcp_subflow_ctx(const struct sock * sk)457 mptcp_subflow_ctx(const struct sock *sk)
458 {
459 struct inet_connection_sock *icsk = inet_csk(sk);
460
461 /* Use RCU on icsk_ulp_data only for sock diag code */
462 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data;
463 }
464
465 static inline struct sock *
mptcp_subflow_tcp_sock(const struct mptcp_subflow_context * subflow)466 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
467 {
468 return subflow->tcp_sock;
469 }
470
471 static inline u64
mptcp_subflow_get_map_offset(const struct mptcp_subflow_context * subflow)472 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow)
473 {
474 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq -
475 subflow->ssn_offset -
476 subflow->map_subflow_seq;
477 }
478
479 static inline u64
mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context * subflow)480 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow)
481 {
482 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow);
483 }
484
mptcp_add_pending_subflow(struct mptcp_sock * msk,struct mptcp_subflow_context * subflow)485 static inline void mptcp_add_pending_subflow(struct mptcp_sock *msk,
486 struct mptcp_subflow_context *subflow)
487 {
488 sock_hold(mptcp_subflow_tcp_sock(subflow));
489 spin_lock_bh(&msk->join_list_lock);
490 list_add_tail(&subflow->node, &msk->join_list);
491 spin_unlock_bh(&msk->join_list_lock);
492 }
493
494 void mptcp_subflow_process_delegated(struct sock *ssk);
495
mptcp_subflow_delegate(struct mptcp_subflow_context * subflow,int action)496 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action)
497 {
498 struct mptcp_delegated_action *delegated;
499 bool schedule;
500
501 /* the caller held the subflow bh socket lock */
502 lockdep_assert_in_softirq();
503
504 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and
505 * ensures the below list check sees list updates done prior to status
506 * bit changes
507 */
508 if (!test_and_set_bit(action, &subflow->delegated_status)) {
509 /* still on delegated list from previous scheduling */
510 if (!list_empty(&subflow->delegated_node))
511 return;
512
513 delegated = this_cpu_ptr(&mptcp_delegated_actions);
514 schedule = list_empty(&delegated->head);
515 list_add_tail(&subflow->delegated_node, &delegated->head);
516 sock_hold(mptcp_subflow_tcp_sock(subflow));
517 if (schedule)
518 napi_schedule(&delegated->napi);
519 }
520 }
521
522 static inline struct mptcp_subflow_context *
mptcp_subflow_delegated_next(struct mptcp_delegated_action * delegated)523 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated)
524 {
525 struct mptcp_subflow_context *ret;
526
527 if (list_empty(&delegated->head))
528 return NULL;
529
530 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node);
531 list_del_init(&ret->delegated_node);
532 return ret;
533 }
534
mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context * subflow)535 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow)
536 {
537 return !!READ_ONCE(subflow->delegated_status);
538 }
539
mptcp_subflow_delegated_done(struct mptcp_subflow_context * subflow,int action)540 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action)
541 {
542 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before
543 * touching the status bit
544 */
545 smp_wmb();
546 clear_bit(action, &subflow->delegated_status);
547 }
548
549 int mptcp_is_enabled(const struct net *net);
550 unsigned int mptcp_get_add_addr_timeout(const struct net *net);
551 int mptcp_is_checksum_enabled(const struct net *net);
552 int mptcp_allow_join_id0(const struct net *net);
553 unsigned int mptcp_stale_loss_cnt(const struct net *net);
554 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow,
555 struct mptcp_options_received *mp_opt);
556 bool __mptcp_retransmit_pending_data(struct sock *sk);
557 void __mptcp_push_pending(struct sock *sk, unsigned int flags);
558 bool mptcp_subflow_data_available(struct sock *sk);
559 void __init mptcp_subflow_init(void);
560 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how);
561 void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
562 struct mptcp_subflow_context *subflow);
563 void mptcp_subflow_send_ack(struct sock *ssk);
564 void mptcp_subflow_reset(struct sock *ssk);
565 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
566 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk);
567
568 /* called with sk socket lock held */
569 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc,
570 const struct mptcp_addr_info *remote);
571 int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock);
572 void mptcp_info2sockaddr(const struct mptcp_addr_info *info,
573 struct sockaddr_storage *addr,
574 unsigned short family);
575
__mptcp_subflow_active(struct mptcp_subflow_context * subflow)576 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow)
577 {
578 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
579
580 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */
581 if (subflow->request_join && !subflow->fully_established)
582 return false;
583
584 /* only send if our side has not closed yet */
585 return ((1 << ssk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT));
586 }
587
588 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow);
589
590 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow);
591
mptcp_subflow_tcp_fallback(struct sock * sk,struct mptcp_subflow_context * ctx)592 static inline void mptcp_subflow_tcp_fallback(struct sock *sk,
593 struct mptcp_subflow_context *ctx)
594 {
595 sk->sk_data_ready = ctx->tcp_data_ready;
596 sk->sk_state_change = ctx->tcp_state_change;
597 sk->sk_write_space = ctx->tcp_write_space;
598 sk->sk_error_report = ctx->tcp_error_report;
599
600 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops;
601 }
602
mptcp_has_another_subflow(struct sock * ssk)603 static inline bool mptcp_has_another_subflow(struct sock *ssk)
604 {
605 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk), *tmp;
606 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
607
608 mptcp_for_each_subflow(msk, tmp) {
609 if (tmp != subflow)
610 return true;
611 }
612
613 return false;
614 }
615
616 void __init mptcp_proto_init(void);
617 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
618 int __init mptcp_proto_v6_init(void);
619 #endif
620
621 struct sock *mptcp_sk_clone(const struct sock *sk,
622 const struct mptcp_options_received *mp_opt,
623 struct request_sock *req);
624 void mptcp_get_options(const struct sock *sk,
625 const struct sk_buff *skb,
626 struct mptcp_options_received *mp_opt);
627
628 void mptcp_finish_connect(struct sock *sk);
629 void __mptcp_set_connected(struct sock *sk);
mptcp_is_fully_established(struct sock * sk)630 static inline bool mptcp_is_fully_established(struct sock *sk)
631 {
632 return inet_sk_state_load(sk) == TCP_ESTABLISHED &&
633 READ_ONCE(mptcp_sk(sk)->fully_established);
634 }
635 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk);
636 void mptcp_data_ready(struct sock *sk, struct sock *ssk);
637 bool mptcp_finish_join(struct sock *sk);
638 bool mptcp_schedule_work(struct sock *sk);
639 int mptcp_setsockopt(struct sock *sk, int level, int optname,
640 sockptr_t optval, unsigned int optlen);
641 int mptcp_getsockopt(struct sock *sk, int level, int optname,
642 char __user *optval, int __user *option);
643
644 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq);
mptcp_expand_seq(u64 old_seq,u64 cur_seq,bool use_64bit)645 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit)
646 {
647 if (use_64bit)
648 return cur_seq;
649
650 return __mptcp_expand_seq(old_seq, cur_seq);
651 }
652 void __mptcp_check_push(struct sock *sk, struct sock *ssk);
653 void __mptcp_data_acked(struct sock *sk);
654 void __mptcp_error_report(struct sock *sk);
655 void mptcp_subflow_eof(struct sock *sk);
656 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit);
657 void __mptcp_flush_join_list(struct mptcp_sock *msk);
mptcp_data_fin_enabled(const struct mptcp_sock * msk)658 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk)
659 {
660 return READ_ONCE(msk->snd_data_fin_enable) &&
661 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt);
662 }
663
mptcp_propagate_sndbuf(struct sock * sk,struct sock * ssk)664 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk)
665 {
666 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf))
667 return false;
668
669 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf);
670 return true;
671 }
672
mptcp_write_space(struct sock * sk)673 static inline void mptcp_write_space(struct sock *sk)
674 {
675 if (sk_stream_is_writeable(sk)) {
676 /* pairs with memory barrier in mptcp_poll */
677 smp_mb();
678 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags))
679 sk_stream_write_space(sk);
680 }
681 }
682
683 void mptcp_destroy_common(struct mptcp_sock *msk);
684
685 #define MPTCP_TOKEN_MAX_RETRIES 4
686
687 void __init mptcp_token_init(void);
mptcp_token_init_request(struct request_sock * req)688 static inline void mptcp_token_init_request(struct request_sock *req)
689 {
690 mptcp_subflow_rsk(req)->token_node.pprev = NULL;
691 }
692
693 int mptcp_token_new_request(struct request_sock *req);
694 void mptcp_token_destroy_request(struct request_sock *req);
695 int mptcp_token_new_connect(struct sock *sk);
696 void mptcp_token_accept(struct mptcp_subflow_request_sock *r,
697 struct mptcp_sock *msk);
698 bool mptcp_token_exists(u32 token);
699 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token);
700 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot,
701 long *s_num);
702 void mptcp_token_destroy(struct mptcp_sock *msk);
703
704 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn);
705
706 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac);
707
708 void __init mptcp_pm_init(void);
709 void mptcp_pm_data_init(struct mptcp_sock *msk);
710 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
711 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
712 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side);
713 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp);
714 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk);
715 void mptcp_pm_connection_closed(struct mptcp_sock *msk);
716 void mptcp_pm_subflow_established(struct mptcp_sock *msk);
717 void mptcp_pm_subflow_closed(struct mptcp_sock *msk, u8 id);
718 void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
719 const struct mptcp_addr_info *addr);
720 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
721 struct mptcp_addr_info *addr);
722 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk);
723 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk);
724 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
725 const struct mptcp_rm_list *rm_list);
726 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
727 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
728 void mptcp_pm_free_anno_list(struct mptcp_sock *msk);
729 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
730 struct mptcp_pm_add_entry *
731 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
732 struct mptcp_addr_info *addr, bool check_id);
733 struct mptcp_pm_add_entry *
734 mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk,
735 struct mptcp_addr_info *addr);
736 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id,
737 u8 *flags, int *ifindex);
738
739 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
740 const struct mptcp_addr_info *addr,
741 bool echo);
742 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
743 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
744
745 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
746 const struct sock *ssk, gfp_t gfp);
747 void mptcp_event_addr_announced(const struct mptcp_sock *msk, const struct mptcp_addr_info *info);
748 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id);
749
mptcp_pm_should_add_signal(struct mptcp_sock * msk)750 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk)
751 {
752 return READ_ONCE(msk->pm.addr_signal) &
753 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO));
754 }
755
mptcp_pm_should_add_signal_addr(struct mptcp_sock * msk)756 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk)
757 {
758 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL);
759 }
760
mptcp_pm_should_add_signal_echo(struct mptcp_sock * msk)761 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk)
762 {
763 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO);
764 }
765
mptcp_pm_should_rm_signal(struct mptcp_sock * msk)766 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)
767 {
768 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL);
769 }
770
mptcp_add_addr_len(int family,bool echo,bool port)771 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port)
772 {
773 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE;
774
775 if (family == AF_INET6)
776 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE;
777 if (!echo)
778 len += MPTCPOPT_THMAC_LEN;
779 /* account for 2 trailing 'nop' options */
780 if (port)
781 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN;
782
783 return len;
784 }
785
mptcp_rm_addr_len(const struct mptcp_rm_list * rm_list)786 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list)
787 {
788 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX)
789 return -EINVAL;
790
791 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1;
792 }
793
794 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct sk_buff *skb,
795 unsigned int opt_size, unsigned int remaining,
796 struct mptcp_addr_info *addr, bool *echo,
797 bool *port, bool *drop_other_suboptions);
798 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
799 struct mptcp_rm_list *rm_list);
800 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
801
802 void __init mptcp_pm_nl_init(void);
803 void mptcp_pm_nl_data_init(struct mptcp_sock *msk);
804 void mptcp_pm_nl_work(struct mptcp_sock *msk);
805 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
806 const struct mptcp_rm_list *rm_list);
807 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
808 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk);
809 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk);
810 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk);
811 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk);
812
813 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk);
814 void mptcp_sockopt_sync_all(struct mptcp_sock *msk);
815
mptcp_get_ext(const struct sk_buff * skb)816 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb)
817 {
818 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP);
819 }
820
821 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops);
822
__mptcp_check_fallback(const struct mptcp_sock * msk)823 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk)
824 {
825 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags);
826 }
827
mptcp_check_fallback(const struct sock * sk)828 static inline bool mptcp_check_fallback(const struct sock *sk)
829 {
830 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
831 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
832
833 return __mptcp_check_fallback(msk);
834 }
835
__mptcp_do_fallback(struct mptcp_sock * msk)836 static inline void __mptcp_do_fallback(struct mptcp_sock *msk)
837 {
838 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) {
839 pr_debug("TCP fallback already done (msk=%p)", msk);
840 return;
841 }
842 set_bit(MPTCP_FALLBACK_DONE, &msk->flags);
843 }
844
mptcp_do_fallback(struct sock * sk)845 static inline void mptcp_do_fallback(struct sock *sk)
846 {
847 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
848 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
849
850 __mptcp_do_fallback(msk);
851 }
852
853 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a)
854
subflow_simultaneous_connect(struct sock * sk)855 static inline bool subflow_simultaneous_connect(struct sock *sk)
856 {
857 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
858 struct sock *parent = subflow->conn;
859
860 return sk->sk_state == TCP_ESTABLISHED &&
861 !mptcp_sk(parent)->pm.server_side &&
862 !subflow->conn_finished;
863 }
864
865 #ifdef CONFIG_SYN_COOKIES
866 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
867 struct sk_buff *skb);
868 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
869 struct sk_buff *skb);
870 void __init mptcp_join_cookie_init(void);
871 #else
872 static inline void
subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)873 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req,
874 struct sk_buff *skb) {}
875 static inline bool
mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock * subflow_req,struct sk_buff * skb)876 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req,
877 struct sk_buff *skb)
878 {
879 return false;
880 }
881
mptcp_join_cookie_init(void)882 static inline void mptcp_join_cookie_init(void) {}
883 #endif
884
885 #endif /* __MPTCP_PROTOCOL_H */
886