Commit | Line | Data |
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f870fa0b MM |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Multipath TCP | |
3 | * | |
4 | * Copyright (c) 2017 - 2019, Intel Corporation. | |
5 | */ | |
6 | ||
7 | #define pr_fmt(fmt) "MPTCP: " fmt | |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/netdevice.h> | |
7a6a6cbc PA |
12 | #include <linux/sched/signal.h> |
13 | #include <linux/atomic.h> | |
f870fa0b MM |
14 | #include <net/sock.h> |
15 | #include <net/inet_common.h> | |
16 | #include <net/inet_hashtables.h> | |
17 | #include <net/protocol.h> | |
18 | #include <net/tcp.h> | |
3721b9b6 | 19 | #include <net/tcp_states.h> |
cf7da0d6 PK |
20 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
21 | #include <net/transp_v6.h> | |
22 | #endif | |
f870fa0b MM |
23 | #include <net/mptcp.h> |
24 | #include "protocol.h" | |
fc518953 | 25 | #include "mib.h" |
f870fa0b | 26 | |
b0519de8 FW |
27 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
28 | struct mptcp6_sock { | |
29 | struct mptcp_sock msk; | |
30 | struct ipv6_pinfo np; | |
31 | }; | |
32 | #endif | |
33 | ||
6771bfd9 | 34 | struct mptcp_skb_cb { |
ab174ad8 PA |
35 | u64 map_seq; |
36 | u64 end_seq; | |
6771bfd9 FW |
37 | u32 offset; |
38 | }; | |
39 | ||
40 | #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) | |
41 | ||
d027236c PA |
42 | static struct percpu_counter mptcp_sockets_allocated; |
43 | ||
2303f994 PK |
44 | /* If msk has an initial subflow socket, and the MP_CAPABLE handshake has not |
45 | * completed yet or has failed, return the subflow socket. | |
46 | * Otherwise return NULL. | |
47 | */ | |
48 | static struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk) | |
49 | { | |
d22f4988 | 50 | if (!msk->subflow || READ_ONCE(msk->can_ack)) |
2303f994 PK |
51 | return NULL; |
52 | ||
53 | return msk->subflow; | |
54 | } | |
55 | ||
d2f77c53 | 56 | static bool mptcp_is_tcpsk(struct sock *sk) |
0b4f33de FW |
57 | { |
58 | struct socket *sock = sk->sk_socket; | |
59 | ||
0b4f33de FW |
60 | if (unlikely(sk->sk_prot == &tcp_prot)) { |
61 | /* we are being invoked after mptcp_accept() has | |
62 | * accepted a non-mp-capable flow: sk is a tcp_sk, | |
63 | * not an mptcp one. | |
64 | * | |
65 | * Hand the socket over to tcp so all further socket ops | |
66 | * bypass mptcp. | |
67 | */ | |
68 | sock->ops = &inet_stream_ops; | |
d2f77c53 | 69 | return true; |
0b4f33de FW |
70 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
71 | } else if (unlikely(sk->sk_prot == &tcpv6_prot)) { | |
72 | sock->ops = &inet6_stream_ops; | |
d2f77c53 | 73 | return true; |
0b4f33de FW |
74 | #endif |
75 | } | |
76 | ||
d2f77c53 | 77 | return false; |
0b4f33de FW |
78 | } |
79 | ||
76660afb | 80 | static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk) |
cec37a6e | 81 | { |
cec37a6e PK |
82 | sock_owned_by_me((const struct sock *)msk); |
83 | ||
e1ff9e82 | 84 | if (likely(!__mptcp_check_fallback(msk))) |
cec37a6e PK |
85 | return NULL; |
86 | ||
76660afb | 87 | return msk->first; |
cec37a6e PK |
88 | } |
89 | ||
fa68018d | 90 | static int __mptcp_socket_create(struct mptcp_sock *msk) |
2303f994 PK |
91 | { |
92 | struct mptcp_subflow_context *subflow; | |
93 | struct sock *sk = (struct sock *)msk; | |
94 | struct socket *ssock; | |
95 | int err; | |
96 | ||
2303f994 PK |
97 | err = mptcp_subflow_create_socket(sk, &ssock); |
98 | if (err) | |
fa68018d | 99 | return err; |
2303f994 | 100 | |
8ab183de | 101 | msk->first = ssock->sk; |
2303f994 PK |
102 | msk->subflow = ssock; |
103 | subflow = mptcp_subflow_ctx(ssock->sk); | |
cec37a6e | 104 | list_add(&subflow->node, &msk->conn_list); |
2303f994 PK |
105 | subflow->request_mptcp = 1; |
106 | ||
e1ff9e82 DC |
107 | /* accept() will wait on first subflow sk_wq, and we always wakes up |
108 | * via msk->sk_socket | |
109 | */ | |
110 | RCU_INIT_POINTER(msk->first->sk_wq, &sk->sk_socket->wq); | |
111 | ||
fa68018d | 112 | return 0; |
2303f994 PK |
113 | } |
114 | ||
ab174ad8 PA |
115 | static void mptcp_drop(struct sock *sk, struct sk_buff *skb) |
116 | { | |
117 | sk_drops_add(sk, skb); | |
118 | __kfree_skb(skb); | |
119 | } | |
120 | ||
8268ed4c PA |
121 | static bool mptcp_try_coalesce(struct sock *sk, struct sk_buff *to, |
122 | struct sk_buff *from) | |
123 | { | |
124 | bool fragstolen; | |
125 | int delta; | |
126 | ||
127 | if (MPTCP_SKB_CB(from)->offset || | |
128 | !skb_try_coalesce(to, from, &fragstolen, &delta)) | |
129 | return false; | |
130 | ||
06242e44 PA |
131 | pr_debug("colesced seq %llx into %llx new len %d new end seq %llx", |
132 | MPTCP_SKB_CB(from)->map_seq, MPTCP_SKB_CB(to)->map_seq, | |
133 | to->len, MPTCP_SKB_CB(from)->end_seq); | |
ab174ad8 | 134 | MPTCP_SKB_CB(to)->end_seq = MPTCP_SKB_CB(from)->end_seq; |
8268ed4c PA |
135 | kfree_skb_partial(from, fragstolen); |
136 | atomic_add(delta, &sk->sk_rmem_alloc); | |
137 | sk_mem_charge(sk, delta); | |
138 | return true; | |
139 | } | |
140 | ||
ab174ad8 PA |
141 | static bool mptcp_ooo_try_coalesce(struct mptcp_sock *msk, struct sk_buff *to, |
142 | struct sk_buff *from) | |
143 | { | |
144 | if (MPTCP_SKB_CB(from)->map_seq != MPTCP_SKB_CB(to)->end_seq) | |
145 | return false; | |
146 | ||
147 | return mptcp_try_coalesce((struct sock *)msk, to, from); | |
148 | } | |
149 | ||
150 | /* "inspired" by tcp_data_queue_ofo(), main differences: | |
151 | * - use mptcp seqs | |
152 | * - don't cope with sacks | |
153 | */ | |
154 | static void mptcp_data_queue_ofo(struct mptcp_sock *msk, struct sk_buff *skb) | |
155 | { | |
156 | struct sock *sk = (struct sock *)msk; | |
157 | struct rb_node **p, *parent; | |
158 | u64 seq, end_seq, max_seq; | |
159 | struct sk_buff *skb1; | |
c2ec6bc0 | 160 | int space; |
ab174ad8 PA |
161 | |
162 | seq = MPTCP_SKB_CB(skb)->map_seq; | |
163 | end_seq = MPTCP_SKB_CB(skb)->end_seq; | |
c2ec6bc0 YB |
164 | space = tcp_space(sk); |
165 | max_seq = space > 0 ? space + msk->ack_seq : msk->ack_seq; | |
ab174ad8 | 166 | |
06242e44 PA |
167 | pr_debug("msk=%p seq=%llx limit=%llx empty=%d", msk, seq, max_seq, |
168 | RB_EMPTY_ROOT(&msk->out_of_order_queue)); | |
ab174ad8 PA |
169 | if (after64(seq, max_seq)) { |
170 | /* out of window */ | |
171 | mptcp_drop(sk, skb); | |
06242e44 | 172 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_NODSSWINDOW); |
ab174ad8 PA |
173 | return; |
174 | } | |
175 | ||
176 | p = &msk->out_of_order_queue.rb_node; | |
06242e44 | 177 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOQUEUE); |
ab174ad8 PA |
178 | if (RB_EMPTY_ROOT(&msk->out_of_order_queue)) { |
179 | rb_link_node(&skb->rbnode, NULL, p); | |
180 | rb_insert_color(&skb->rbnode, &msk->out_of_order_queue); | |
181 | msk->ooo_last_skb = skb; | |
182 | goto end; | |
183 | } | |
184 | ||
185 | /* with 2 subflows, adding at end of ooo queue is quite likely | |
186 | * Use of ooo_last_skb avoids the O(Log(N)) rbtree lookup. | |
187 | */ | |
06242e44 PA |
188 | if (mptcp_ooo_try_coalesce(msk, msk->ooo_last_skb, skb)) { |
189 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOMERGE); | |
190 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOQUEUETAIL); | |
ab174ad8 | 191 | return; |
06242e44 | 192 | } |
ab174ad8 PA |
193 | |
194 | /* Can avoid an rbtree lookup if we are adding skb after ooo_last_skb */ | |
195 | if (!before64(seq, MPTCP_SKB_CB(msk->ooo_last_skb)->end_seq)) { | |
06242e44 | 196 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOQUEUETAIL); |
ab174ad8 PA |
197 | parent = &msk->ooo_last_skb->rbnode; |
198 | p = &parent->rb_right; | |
199 | goto insert; | |
200 | } | |
201 | ||
202 | /* Find place to insert this segment. Handle overlaps on the way. */ | |
203 | parent = NULL; | |
204 | while (*p) { | |
205 | parent = *p; | |
206 | skb1 = rb_to_skb(parent); | |
207 | if (before64(seq, MPTCP_SKB_CB(skb1)->map_seq)) { | |
208 | p = &parent->rb_left; | |
209 | continue; | |
210 | } | |
211 | if (before64(seq, MPTCP_SKB_CB(skb1)->end_seq)) { | |
212 | if (!after64(end_seq, MPTCP_SKB_CB(skb1)->end_seq)) { | |
213 | /* All the bits are present. Drop. */ | |
214 | mptcp_drop(sk, skb); | |
06242e44 | 215 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
216 | return; |
217 | } | |
218 | if (after64(seq, MPTCP_SKB_CB(skb1)->map_seq)) { | |
219 | /* partial overlap: | |
220 | * | skb | | |
221 | * | skb1 | | |
222 | * continue traversing | |
223 | */ | |
224 | } else { | |
225 | /* skb's seq == skb1's seq and skb covers skb1. | |
226 | * Replace skb1 with skb. | |
227 | */ | |
228 | rb_replace_node(&skb1->rbnode, &skb->rbnode, | |
229 | &msk->out_of_order_queue); | |
230 | mptcp_drop(sk, skb1); | |
06242e44 | 231 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
232 | goto merge_right; |
233 | } | |
234 | } else if (mptcp_ooo_try_coalesce(msk, skb1, skb)) { | |
06242e44 | 235 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_OFOMERGE); |
ab174ad8 PA |
236 | return; |
237 | } | |
238 | p = &parent->rb_right; | |
239 | } | |
06242e44 | 240 | |
ab174ad8 PA |
241 | insert: |
242 | /* Insert segment into RB tree. */ | |
243 | rb_link_node(&skb->rbnode, parent, p); | |
244 | rb_insert_color(&skb->rbnode, &msk->out_of_order_queue); | |
245 | ||
246 | merge_right: | |
247 | /* Remove other segments covered by skb. */ | |
248 | while ((skb1 = skb_rb_next(skb)) != NULL) { | |
249 | if (before64(end_seq, MPTCP_SKB_CB(skb1)->end_seq)) | |
250 | break; | |
251 | rb_erase(&skb1->rbnode, &msk->out_of_order_queue); | |
252 | mptcp_drop(sk, skb1); | |
06242e44 | 253 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
254 | } |
255 | /* If there is no skb after us, we are the last_skb ! */ | |
256 | if (!skb1) | |
257 | msk->ooo_last_skb = skb; | |
258 | ||
259 | end: | |
260 | skb_condense(skb); | |
261 | skb_set_owner_r(skb, sk); | |
262 | } | |
263 | ||
264 | static bool __mptcp_move_skb(struct mptcp_sock *msk, struct sock *ssk, | |
265 | struct sk_buff *skb, unsigned int offset, | |
266 | size_t copy_len) | |
6771bfd9 | 267 | { |
ab174ad8 | 268 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
6771bfd9 | 269 | struct sock *sk = (struct sock *)msk; |
4e637c70 | 270 | struct sk_buff *tail; |
6771bfd9 FW |
271 | |
272 | __skb_unlink(skb, &ssk->sk_receive_queue); | |
6771bfd9 | 273 | |
4e637c70 FW |
274 | skb_ext_reset(skb); |
275 | skb_orphan(skb); | |
ab174ad8 PA |
276 | |
277 | /* the skb map_seq accounts for the skb offset: | |
278 | * mptcp_subflow_get_mapped_dsn() is based on the current tp->copied_seq | |
279 | * value | |
280 | */ | |
281 | MPTCP_SKB_CB(skb)->map_seq = mptcp_subflow_get_mapped_dsn(subflow); | |
282 | MPTCP_SKB_CB(skb)->end_seq = MPTCP_SKB_CB(skb)->map_seq + copy_len; | |
8268ed4c | 283 | MPTCP_SKB_CB(skb)->offset = offset; |
4e637c70 | 284 | |
ab174ad8 PA |
285 | if (MPTCP_SKB_CB(skb)->map_seq == msk->ack_seq) { |
286 | /* in sequence */ | |
287 | msk->ack_seq += copy_len; | |
288 | tail = skb_peek_tail(&sk->sk_receive_queue); | |
289 | if (tail && mptcp_try_coalesce(sk, tail, skb)) | |
290 | return true; | |
4e637c70 | 291 | |
ab174ad8 PA |
292 | skb_set_owner_r(skb, sk); |
293 | __skb_queue_tail(&sk->sk_receive_queue, skb); | |
294 | return true; | |
295 | } else if (after64(MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq)) { | |
296 | mptcp_data_queue_ofo(msk, skb); | |
297 | return false; | |
298 | } | |
299 | ||
300 | /* old data, keep it simple and drop the whole pkt, sender | |
301 | * will retransmit as needed, if needed. | |
302 | */ | |
06242e44 | 303 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
304 | mptcp_drop(sk, skb); |
305 | return false; | |
6771bfd9 FW |
306 | } |
307 | ||
16a9a9da MM |
308 | static void mptcp_stop_timer(struct sock *sk) |
309 | { | |
310 | struct inet_connection_sock *icsk = inet_csk(sk); | |
311 | ||
312 | sk_stop_timer(sk, &icsk->icsk_retransmit_timer); | |
313 | mptcp_sk(sk)->timer_ival = 0; | |
314 | } | |
315 | ||
16a9a9da MM |
316 | static void mptcp_check_data_fin_ack(struct sock *sk) |
317 | { | |
318 | struct mptcp_sock *msk = mptcp_sk(sk); | |
319 | ||
320 | if (__mptcp_check_fallback(msk)) | |
321 | return; | |
322 | ||
323 | /* Look for an acknowledged DATA_FIN */ | |
324 | if (((1 << sk->sk_state) & | |
325 | (TCPF_FIN_WAIT1 | TCPF_CLOSING | TCPF_LAST_ACK)) && | |
326 | msk->write_seq == atomic64_read(&msk->snd_una)) { | |
327 | mptcp_stop_timer(sk); | |
328 | ||
329 | WRITE_ONCE(msk->snd_data_fin_enable, 0); | |
330 | ||
331 | switch (sk->sk_state) { | |
332 | case TCP_FIN_WAIT1: | |
333 | inet_sk_state_store(sk, TCP_FIN_WAIT2); | |
334 | sk->sk_state_change(sk); | |
335 | break; | |
336 | case TCP_CLOSING: | |
16a9a9da MM |
337 | case TCP_LAST_ACK: |
338 | inet_sk_state_store(sk, TCP_CLOSE); | |
339 | sk->sk_state_change(sk); | |
340 | break; | |
341 | } | |
342 | ||
343 | if (sk->sk_shutdown == SHUTDOWN_MASK || | |
344 | sk->sk_state == TCP_CLOSE) | |
345 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); | |
346 | else | |
347 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); | |
348 | } | |
349 | } | |
350 | ||
3721b9b6 MM |
351 | static bool mptcp_pending_data_fin(struct sock *sk, u64 *seq) |
352 | { | |
353 | struct mptcp_sock *msk = mptcp_sk(sk); | |
354 | ||
355 | if (READ_ONCE(msk->rcv_data_fin) && | |
356 | ((1 << sk->sk_state) & | |
357 | (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2))) { | |
358 | u64 rcv_data_fin_seq = READ_ONCE(msk->rcv_data_fin_seq); | |
359 | ||
360 | if (msk->ack_seq == rcv_data_fin_seq) { | |
361 | if (seq) | |
362 | *seq = rcv_data_fin_seq; | |
363 | ||
364 | return true; | |
365 | } | |
366 | } | |
367 | ||
368 | return false; | |
369 | } | |
370 | ||
371 | static void mptcp_set_timeout(const struct sock *sk, const struct sock *ssk) | |
372 | { | |
373 | long tout = ssk && inet_csk(ssk)->icsk_pending ? | |
374 | inet_csk(ssk)->icsk_timeout - jiffies : 0; | |
375 | ||
376 | if (tout <= 0) | |
377 | tout = mptcp_sk(sk)->timer_ival; | |
378 | mptcp_sk(sk)->timer_ival = tout > 0 ? tout : TCP_RTO_MIN; | |
379 | } | |
380 | ||
381 | static void mptcp_check_data_fin(struct sock *sk) | |
382 | { | |
383 | struct mptcp_sock *msk = mptcp_sk(sk); | |
384 | u64 rcv_data_fin_seq; | |
385 | ||
386 | if (__mptcp_check_fallback(msk) || !msk->first) | |
387 | return; | |
388 | ||
389 | /* Need to ack a DATA_FIN received from a peer while this side | |
390 | * of the connection is in ESTABLISHED, FIN_WAIT1, or FIN_WAIT2. | |
391 | * msk->rcv_data_fin was set when parsing the incoming options | |
392 | * at the subflow level and the msk lock was not held, so this | |
393 | * is the first opportunity to act on the DATA_FIN and change | |
394 | * the msk state. | |
395 | * | |
396 | * If we are caught up to the sequence number of the incoming | |
397 | * DATA_FIN, send the DATA_ACK now and do state transition. If | |
398 | * not caught up, do nothing and let the recv code send DATA_ACK | |
399 | * when catching up. | |
400 | */ | |
401 | ||
402 | if (mptcp_pending_data_fin(sk, &rcv_data_fin_seq)) { | |
403 | struct mptcp_subflow_context *subflow; | |
404 | ||
405 | msk->ack_seq++; | |
406 | WRITE_ONCE(msk->rcv_data_fin, 0); | |
407 | ||
408 | sk->sk_shutdown |= RCV_SHUTDOWN; | |
16a9a9da MM |
409 | smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ |
410 | set_bit(MPTCP_DATA_READY, &msk->flags); | |
3721b9b6 MM |
411 | |
412 | switch (sk->sk_state) { | |
413 | case TCP_ESTABLISHED: | |
414 | inet_sk_state_store(sk, TCP_CLOSE_WAIT); | |
415 | break; | |
416 | case TCP_FIN_WAIT1: | |
417 | inet_sk_state_store(sk, TCP_CLOSING); | |
418 | break; | |
419 | case TCP_FIN_WAIT2: | |
420 | inet_sk_state_store(sk, TCP_CLOSE); | |
421 | // @@ Close subflows now? | |
422 | break; | |
423 | default: | |
424 | /* Other states not expected */ | |
425 | WARN_ON_ONCE(1); | |
426 | break; | |
427 | } | |
428 | ||
429 | mptcp_set_timeout(sk, NULL); | |
430 | mptcp_for_each_subflow(msk, subflow) { | |
431 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
432 | ||
433 | lock_sock(ssk); | |
434 | tcp_send_ack(ssk); | |
435 | release_sock(ssk); | |
436 | } | |
437 | ||
438 | sk->sk_state_change(sk); | |
439 | ||
440 | if (sk->sk_shutdown == SHUTDOWN_MASK || | |
441 | sk->sk_state == TCP_CLOSE) | |
442 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_HUP); | |
443 | else | |
444 | sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); | |
445 | } | |
446 | } | |
447 | ||
6771bfd9 FW |
448 | static bool __mptcp_move_skbs_from_subflow(struct mptcp_sock *msk, |
449 | struct sock *ssk, | |
450 | unsigned int *bytes) | |
451 | { | |
452 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
600911ff | 453 | struct sock *sk = (struct sock *)msk; |
6771bfd9 FW |
454 | unsigned int moved = 0; |
455 | bool more_data_avail; | |
456 | struct tcp_sock *tp; | |
457 | bool done = false; | |
600911ff | 458 | |
ab174ad8 | 459 | pr_debug("msk=%p ssk=%p", msk, ssk); |
6771bfd9 FW |
460 | tp = tcp_sk(ssk); |
461 | do { | |
462 | u32 map_remaining, offset; | |
463 | u32 seq = tp->copied_seq; | |
464 | struct sk_buff *skb; | |
465 | bool fin; | |
466 | ||
467 | /* try to move as much data as available */ | |
468 | map_remaining = subflow->map_data_len - | |
469 | mptcp_subflow_get_map_offset(subflow); | |
470 | ||
471 | skb = skb_peek(&ssk->sk_receive_queue); | |
472 | if (!skb) | |
473 | break; | |
474 | ||
e1ff9e82 DC |
475 | if (__mptcp_check_fallback(msk)) { |
476 | /* if we are running under the workqueue, TCP could have | |
477 | * collapsed skbs between dummy map creation and now | |
478 | * be sure to adjust the size | |
479 | */ | |
480 | map_remaining = skb->len; | |
481 | subflow->map_data_len = skb->len; | |
482 | } | |
483 | ||
6771bfd9 FW |
484 | offset = seq - TCP_SKB_CB(skb)->seq; |
485 | fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; | |
486 | if (fin) { | |
487 | done = true; | |
488 | seq++; | |
489 | } | |
490 | ||
491 | if (offset < skb->len) { | |
492 | size_t len = skb->len - offset; | |
493 | ||
494 | if (tp->urg_data) | |
495 | done = true; | |
496 | ||
ab174ad8 PA |
497 | if (__mptcp_move_skb(msk, ssk, skb, offset, len)) |
498 | moved += len; | |
6771bfd9 | 499 | seq += len; |
6771bfd9 FW |
500 | |
501 | if (WARN_ON_ONCE(map_remaining < len)) | |
502 | break; | |
503 | } else { | |
504 | WARN_ON_ONCE(!fin); | |
505 | sk_eat_skb(ssk, skb); | |
506 | done = true; | |
507 | } | |
508 | ||
509 | WRITE_ONCE(tp->copied_seq, seq); | |
510 | more_data_avail = mptcp_subflow_data_available(ssk); | |
600911ff FW |
511 | |
512 | if (atomic_read(&sk->sk_rmem_alloc) > READ_ONCE(sk->sk_rcvbuf)) { | |
513 | done = true; | |
514 | break; | |
515 | } | |
6771bfd9 FW |
516 | } while (more_data_avail); |
517 | ||
6719331c | 518 | *bytes += moved; |
c76c6956 PA |
519 | if (moved) |
520 | tcp_cleanup_rbuf(ssk, moved); | |
6771bfd9 FW |
521 | |
522 | return done; | |
523 | } | |
524 | ||
ab174ad8 PA |
525 | static bool mptcp_ofo_queue(struct mptcp_sock *msk) |
526 | { | |
527 | struct sock *sk = (struct sock *)msk; | |
528 | struct sk_buff *skb, *tail; | |
529 | bool moved = false; | |
530 | struct rb_node *p; | |
531 | u64 end_seq; | |
532 | ||
533 | p = rb_first(&msk->out_of_order_queue); | |
06242e44 | 534 | pr_debug("msk=%p empty=%d", msk, RB_EMPTY_ROOT(&msk->out_of_order_queue)); |
ab174ad8 PA |
535 | while (p) { |
536 | skb = rb_to_skb(p); | |
537 | if (after64(MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq)) | |
538 | break; | |
539 | ||
540 | p = rb_next(p); | |
541 | rb_erase(&skb->rbnode, &msk->out_of_order_queue); | |
542 | ||
543 | if (unlikely(!after64(MPTCP_SKB_CB(skb)->end_seq, | |
544 | msk->ack_seq))) { | |
545 | mptcp_drop(sk, skb); | |
06242e44 | 546 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_DUPDATA); |
ab174ad8 PA |
547 | continue; |
548 | } | |
549 | ||
550 | end_seq = MPTCP_SKB_CB(skb)->end_seq; | |
551 | tail = skb_peek_tail(&sk->sk_receive_queue); | |
552 | if (!tail || !mptcp_ooo_try_coalesce(msk, tail, skb)) { | |
553 | int delta = msk->ack_seq - MPTCP_SKB_CB(skb)->map_seq; | |
554 | ||
555 | /* skip overlapping data, if any */ | |
06242e44 PA |
556 | pr_debug("uncoalesced seq=%llx ack seq=%llx delta=%d", |
557 | MPTCP_SKB_CB(skb)->map_seq, msk->ack_seq, | |
558 | delta); | |
ab174ad8 PA |
559 | MPTCP_SKB_CB(skb)->offset += delta; |
560 | __skb_queue_tail(&sk->sk_receive_queue, skb); | |
561 | } | |
562 | msk->ack_seq = end_seq; | |
563 | moved = true; | |
564 | } | |
565 | return moved; | |
566 | } | |
567 | ||
2e52213c FW |
568 | /* In most cases we will be able to lock the mptcp socket. If its already |
569 | * owned, we need to defer to the work queue to avoid ABBA deadlock. | |
570 | */ | |
571 | static bool move_skbs_to_msk(struct mptcp_sock *msk, struct sock *ssk) | |
572 | { | |
573 | struct sock *sk = (struct sock *)msk; | |
574 | unsigned int moved = 0; | |
575 | ||
576 | if (READ_ONCE(sk->sk_lock.owned)) | |
577 | return false; | |
578 | ||
579 | if (unlikely(!spin_trylock_bh(&sk->sk_lock.slock))) | |
580 | return false; | |
581 | ||
582 | /* must re-check after taking the lock */ | |
ab174ad8 | 583 | if (!READ_ONCE(sk->sk_lock.owned)) { |
2e52213c | 584 | __mptcp_move_skbs_from_subflow(msk, ssk, &moved); |
ab174ad8 PA |
585 | mptcp_ofo_queue(msk); |
586 | ||
587 | /* If the moves have caught up with the DATA_FIN sequence number | |
588 | * it's time to ack the DATA_FIN and change socket state, but | |
589 | * this is not a good place to change state. Let the workqueue | |
590 | * do it. | |
591 | */ | |
592 | if (mptcp_pending_data_fin(sk, NULL) && | |
593 | schedule_work(&msk->work)) | |
594 | sock_hold(sk); | |
595 | } | |
2e52213c FW |
596 | |
597 | spin_unlock_bh(&sk->sk_lock.slock); | |
598 | ||
599 | return moved > 0; | |
600 | } | |
601 | ||
602 | void mptcp_data_ready(struct sock *sk, struct sock *ssk) | |
101f6f85 | 603 | { |
6719331c | 604 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
101f6f85 | 605 | struct mptcp_sock *msk = mptcp_sk(sk); |
6719331c | 606 | bool wake; |
101f6f85 | 607 | |
6719331c PA |
608 | /* move_skbs_to_msk below can legitly clear the data_avail flag, |
609 | * but we will need later to properly woke the reader, cache its | |
610 | * value | |
611 | */ | |
612 | wake = subflow->data_avail == MPTCP_SUBFLOW_DATA_AVAIL; | |
613 | if (wake) | |
614 | set_bit(MPTCP_DATA_READY, &msk->flags); | |
6771bfd9 | 615 | |
2e52213c FW |
616 | if (atomic_read(&sk->sk_rmem_alloc) < READ_ONCE(sk->sk_rcvbuf) && |
617 | move_skbs_to_msk(msk, ssk)) | |
618 | goto wake; | |
619 | ||
600911ff FW |
620 | /* don't schedule if mptcp sk is (still) over limit */ |
621 | if (atomic_read(&sk->sk_rmem_alloc) > READ_ONCE(sk->sk_rcvbuf)) | |
622 | goto wake; | |
623 | ||
14c441b5 PA |
624 | /* mptcp socket is owned, release_cb should retry */ |
625 | if (!test_and_set_bit(TCP_DELACK_TIMER_DEFERRED, | |
626 | &sk->sk_tsq_flags)) { | |
627 | sock_hold(sk); | |
6771bfd9 | 628 | |
14c441b5 PA |
629 | /* need to try again, its possible release_cb() has already |
630 | * been called after the test_and_set_bit() above. | |
631 | */ | |
632 | move_skbs_to_msk(msk, ssk); | |
633 | } | |
600911ff | 634 | wake: |
6719331c PA |
635 | if (wake) |
636 | sk->sk_data_ready(sk); | |
101f6f85 FW |
637 | } |
638 | ||
ec3edaa7 PK |
639 | static void __mptcp_flush_join_list(struct mptcp_sock *msk) |
640 | { | |
641 | if (likely(list_empty(&msk->join_list))) | |
642 | return; | |
643 | ||
644 | spin_lock_bh(&msk->join_list_lock); | |
645 | list_splice_tail_init(&msk->join_list, &msk->conn_list); | |
646 | spin_unlock_bh(&msk->join_list_lock); | |
647 | } | |
648 | ||
b51f9b80 PA |
649 | static bool mptcp_timer_pending(struct sock *sk) |
650 | { | |
651 | return timer_pending(&inet_csk(sk)->icsk_retransmit_timer); | |
652 | } | |
653 | ||
654 | static void mptcp_reset_timer(struct sock *sk) | |
655 | { | |
656 | struct inet_connection_sock *icsk = inet_csk(sk); | |
657 | unsigned long tout; | |
658 | ||
659 | /* should never be called with mptcp level timer cleared */ | |
660 | tout = READ_ONCE(mptcp_sk(sk)->timer_ival); | |
661 | if (WARN_ON_ONCE(!tout)) | |
662 | tout = TCP_RTO_MIN; | |
663 | sk_reset_timer(sk, &icsk->icsk_retransmit_timer, jiffies + tout); | |
664 | } | |
665 | ||
666 | void mptcp_data_acked(struct sock *sk) | |
667 | { | |
668 | mptcp_reset_timer(sk); | |
3b1d6210 | 669 | |
63561a40 | 670 | if ((!test_bit(MPTCP_SEND_SPACE, &mptcp_sk(sk)->flags) || |
43b54c6e | 671 | (inet_sk_state_load(sk) != TCP_ESTABLISHED)) && |
3b1d6210 PA |
672 | schedule_work(&mptcp_sk(sk)->work)) |
673 | sock_hold(sk); | |
b51f9b80 PA |
674 | } |
675 | ||
59832e24 FW |
676 | void mptcp_subflow_eof(struct sock *sk) |
677 | { | |
678 | struct mptcp_sock *msk = mptcp_sk(sk); | |
679 | ||
680 | if (!test_and_set_bit(MPTCP_WORK_EOF, &msk->flags) && | |
681 | schedule_work(&msk->work)) | |
682 | sock_hold(sk); | |
683 | } | |
684 | ||
5969856a PA |
685 | static void mptcp_check_for_eof(struct mptcp_sock *msk) |
686 | { | |
687 | struct mptcp_subflow_context *subflow; | |
688 | struct sock *sk = (struct sock *)msk; | |
689 | int receivers = 0; | |
690 | ||
691 | mptcp_for_each_subflow(msk, subflow) | |
692 | receivers += !subflow->rx_eof; | |
693 | ||
694 | if (!receivers && !(sk->sk_shutdown & RCV_SHUTDOWN)) { | |
695 | /* hopefully temporary hack: propagate shutdown status | |
696 | * to msk, when all subflows agree on it | |
697 | */ | |
698 | sk->sk_shutdown |= RCV_SHUTDOWN; | |
699 | ||
700 | smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ | |
701 | set_bit(MPTCP_DATA_READY, &msk->flags); | |
702 | sk->sk_data_ready(sk); | |
703 | } | |
704 | } | |
705 | ||
6d0060f6 MM |
706 | static bool mptcp_ext_cache_refill(struct mptcp_sock *msk) |
707 | { | |
4930f483 FW |
708 | const struct sock *sk = (const struct sock *)msk; |
709 | ||
6d0060f6 | 710 | if (!msk->cached_ext) |
4930f483 | 711 | msk->cached_ext = __skb_ext_alloc(sk->sk_allocation); |
6d0060f6 MM |
712 | |
713 | return !!msk->cached_ext; | |
714 | } | |
715 | ||
7a6a6cbc PA |
716 | static struct sock *mptcp_subflow_recv_lookup(const struct mptcp_sock *msk) |
717 | { | |
718 | struct mptcp_subflow_context *subflow; | |
719 | struct sock *sk = (struct sock *)msk; | |
720 | ||
721 | sock_owned_by_me(sk); | |
722 | ||
723 | mptcp_for_each_subflow(msk, subflow) { | |
724 | if (subflow->data_avail) | |
725 | return mptcp_subflow_tcp_sock(subflow); | |
726 | } | |
727 | ||
728 | return NULL; | |
729 | } | |
730 | ||
3f8e0aae PA |
731 | static bool mptcp_skb_can_collapse_to(u64 write_seq, |
732 | const struct sk_buff *skb, | |
733 | const struct mptcp_ext *mpext) | |
57040755 PA |
734 | { |
735 | if (!tcp_skb_can_collapse_to(skb)) | |
736 | return false; | |
737 | ||
738 | /* can collapse only if MPTCP level sequence is in order */ | |
3f8e0aae | 739 | return mpext && mpext->data_seq + mpext->data_len == write_seq; |
57040755 PA |
740 | } |
741 | ||
18b683bf PA |
742 | static bool mptcp_frag_can_collapse_to(const struct mptcp_sock *msk, |
743 | const struct page_frag *pfrag, | |
744 | const struct mptcp_data_frag *df) | |
745 | { | |
746 | return df && pfrag->page == df->page && | |
747 | df->data_seq + df->data_len == msk->write_seq; | |
748 | } | |
749 | ||
d027236c PA |
750 | static void dfrag_uncharge(struct sock *sk, int len) |
751 | { | |
752 | sk_mem_uncharge(sk, len); | |
7948f6cc | 753 | sk_wmem_queued_add(sk, -len); |
d027236c PA |
754 | } |
755 | ||
756 | static void dfrag_clear(struct sock *sk, struct mptcp_data_frag *dfrag) | |
18b683bf | 757 | { |
d027236c PA |
758 | int len = dfrag->data_len + dfrag->overhead; |
759 | ||
18b683bf | 760 | list_del(&dfrag->list); |
d027236c | 761 | dfrag_uncharge(sk, len); |
18b683bf PA |
762 | put_page(dfrag->page); |
763 | } | |
764 | ||
63561a40 PA |
765 | static bool mptcp_is_writeable(struct mptcp_sock *msk) |
766 | { | |
767 | struct mptcp_subflow_context *subflow; | |
768 | ||
769 | if (!sk_stream_is_writeable((struct sock *)msk)) | |
770 | return false; | |
771 | ||
772 | mptcp_for_each_subflow(msk, subflow) { | |
773 | if (sk_stream_is_writeable(subflow->tcp_sock)) | |
774 | return true; | |
775 | } | |
776 | return false; | |
777 | } | |
778 | ||
18b683bf PA |
779 | static void mptcp_clean_una(struct sock *sk) |
780 | { | |
781 | struct mptcp_sock *msk = mptcp_sk(sk); | |
782 | struct mptcp_data_frag *dtmp, *dfrag; | |
d027236c | 783 | bool cleaned = false; |
e1ff9e82 DC |
784 | u64 snd_una; |
785 | ||
786 | /* on fallback we just need to ignore snd_una, as this is really | |
787 | * plain TCP | |
788 | */ | |
789 | if (__mptcp_check_fallback(msk)) | |
790 | atomic64_set(&msk->snd_una, msk->write_seq); | |
791 | snd_una = atomic64_read(&msk->snd_una); | |
18b683bf PA |
792 | |
793 | list_for_each_entry_safe(dfrag, dtmp, &msk->rtx_queue, list) { | |
794 | if (after64(dfrag->data_seq + dfrag->data_len, snd_una)) | |
795 | break; | |
796 | ||
d027236c PA |
797 | dfrag_clear(sk, dfrag); |
798 | cleaned = true; | |
799 | } | |
800 | ||
7948f6cc FW |
801 | dfrag = mptcp_rtx_head(sk); |
802 | if (dfrag && after64(snd_una, dfrag->data_seq)) { | |
53eb4c38 PA |
803 | u64 delta = snd_una - dfrag->data_seq; |
804 | ||
805 | if (WARN_ON_ONCE(delta > dfrag->data_len)) | |
806 | goto out; | |
7948f6cc FW |
807 | |
808 | dfrag->data_seq += delta; | |
53eb4c38 | 809 | dfrag->offset += delta; |
7948f6cc FW |
810 | dfrag->data_len -= delta; |
811 | ||
812 | dfrag_uncharge(sk, delta); | |
813 | cleaned = true; | |
814 | } | |
815 | ||
53eb4c38 | 816 | out: |
d027236c PA |
817 | if (cleaned) { |
818 | sk_mem_reclaim_partial(sk); | |
7948f6cc FW |
819 | |
820 | /* Only wake up writers if a subflow is ready */ | |
63561a40 PA |
821 | if (mptcp_is_writeable(msk)) { |
822 | set_bit(MPTCP_SEND_SPACE, &mptcp_sk(sk)->flags); | |
823 | smp_mb__after_atomic(); | |
824 | ||
825 | /* set SEND_SPACE before sk_stream_write_space clears | |
826 | * NOSPACE | |
827 | */ | |
7948f6cc | 828 | sk_stream_write_space(sk); |
63561a40 | 829 | } |
18b683bf PA |
830 | } |
831 | } | |
832 | ||
833 | /* ensure we get enough memory for the frag hdr, beyond some minimal amount of | |
834 | * data | |
835 | */ | |
836 | static bool mptcp_page_frag_refill(struct sock *sk, struct page_frag *pfrag) | |
837 | { | |
838 | if (likely(skb_page_frag_refill(32U + sizeof(struct mptcp_data_frag), | |
839 | pfrag, sk->sk_allocation))) | |
840 | return true; | |
841 | ||
842 | sk->sk_prot->enter_memory_pressure(sk); | |
843 | sk_stream_moderate_sndbuf(sk); | |
844 | return false; | |
845 | } | |
846 | ||
847 | static struct mptcp_data_frag * | |
848 | mptcp_carve_data_frag(const struct mptcp_sock *msk, struct page_frag *pfrag, | |
849 | int orig_offset) | |
850 | { | |
851 | int offset = ALIGN(orig_offset, sizeof(long)); | |
852 | struct mptcp_data_frag *dfrag; | |
853 | ||
854 | dfrag = (struct mptcp_data_frag *)(page_to_virt(pfrag->page) + offset); | |
855 | dfrag->data_len = 0; | |
856 | dfrag->data_seq = msk->write_seq; | |
857 | dfrag->overhead = offset - orig_offset + sizeof(struct mptcp_data_frag); | |
858 | dfrag->offset = offset + sizeof(struct mptcp_data_frag); | |
859 | dfrag->page = pfrag->page; | |
860 | ||
861 | return dfrag; | |
862 | } | |
863 | ||
6d0060f6 | 864 | static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, |
3f8e0aae PA |
865 | struct msghdr *msg, struct mptcp_data_frag *dfrag, |
866 | long *timeo, int *pmss_now, | |
57040755 | 867 | int *ps_goal) |
6d0060f6 | 868 | { |
18b683bf PA |
869 | int mss_now, avail_size, size_goal, offset, ret, frag_truesize = 0; |
870 | bool dfrag_collapsed, can_collapse = false; | |
6d0060f6 MM |
871 | struct mptcp_sock *msk = mptcp_sk(sk); |
872 | struct mptcp_ext *mpext = NULL; | |
3f8e0aae | 873 | bool retransmission = !!dfrag; |
57040755 | 874 | struct sk_buff *skb, *tail; |
6d0060f6 | 875 | struct page_frag *pfrag; |
3f8e0aae PA |
876 | struct page *page; |
877 | u64 *write_seq; | |
6d0060f6 MM |
878 | size_t psize; |
879 | ||
880 | /* use the mptcp page cache so that we can easily move the data | |
881 | * from one substream to another, but do per subflow memory accounting | |
3f8e0aae PA |
882 | * Note: pfrag is used only !retransmission, but the compiler if |
883 | * fooled into a warning if we don't init here | |
6d0060f6 MM |
884 | */ |
885 | pfrag = sk_page_frag(sk); | |
3f8e0aae PA |
886 | if (!retransmission) { |
887 | write_seq = &msk->write_seq; | |
888 | page = pfrag->page; | |
889 | } else { | |
890 | write_seq = &dfrag->data_seq; | |
891 | page = dfrag->page; | |
892 | } | |
6d0060f6 MM |
893 | |
894 | /* compute copy limit */ | |
895 | mss_now = tcp_send_mss(ssk, &size_goal, msg->msg_flags); | |
57040755 PA |
896 | *pmss_now = mss_now; |
897 | *ps_goal = size_goal; | |
898 | avail_size = size_goal; | |
899 | skb = tcp_write_queue_tail(ssk); | |
900 | if (skb) { | |
901 | mpext = skb_ext_find(skb, SKB_EXT_MPTCP); | |
902 | ||
903 | /* Limit the write to the size available in the | |
904 | * current skb, if any, so that we create at most a new skb. | |
905 | * Explicitly tells TCP internals to avoid collapsing on later | |
906 | * queue management operation, to avoid breaking the ext <-> | |
907 | * SSN association set here | |
908 | */ | |
909 | can_collapse = (size_goal - skb->len > 0) && | |
3f8e0aae | 910 | mptcp_skb_can_collapse_to(*write_seq, skb, mpext); |
57040755 PA |
911 | if (!can_collapse) |
912 | TCP_SKB_CB(skb)->eor = 1; | |
913 | else | |
914 | avail_size = size_goal - skb->len; | |
915 | } | |
18b683bf | 916 | |
3f8e0aae PA |
917 | if (!retransmission) { |
918 | /* reuse tail pfrag, if possible, or carve a new one from the | |
919 | * page allocator | |
920 | */ | |
921 | dfrag = mptcp_rtx_tail(sk); | |
922 | offset = pfrag->offset; | |
923 | dfrag_collapsed = mptcp_frag_can_collapse_to(msk, pfrag, dfrag); | |
924 | if (!dfrag_collapsed) { | |
925 | dfrag = mptcp_carve_data_frag(msk, pfrag, offset); | |
926 | offset = dfrag->offset; | |
927 | frag_truesize = dfrag->overhead; | |
928 | } | |
929 | psize = min_t(size_t, pfrag->size - offset, avail_size); | |
930 | ||
931 | /* Copy to page */ | |
932 | pr_debug("left=%zu", msg_data_left(msg)); | |
933 | psize = copy_page_from_iter(pfrag->page, offset, | |
934 | min_t(size_t, msg_data_left(msg), | |
935 | psize), | |
936 | &msg->msg_iter); | |
937 | pr_debug("left=%zu", msg_data_left(msg)); | |
938 | if (!psize) | |
939 | return -EINVAL; | |
940 | ||
35759383 FW |
941 | if (!sk_wmem_schedule(sk, psize + dfrag->overhead)) { |
942 | iov_iter_revert(&msg->msg_iter, psize); | |
3f8e0aae | 943 | return -ENOMEM; |
35759383 | 944 | } |
3f8e0aae | 945 | } else { |
18b683bf | 946 | offset = dfrag->offset; |
3f8e0aae | 947 | psize = min_t(size_t, dfrag->data_len, avail_size); |
18b683bf | 948 | } |
d027236c | 949 | |
57040755 PA |
950 | /* tell the TCP stack to delay the push so that we can safely |
951 | * access the skb after the sendpages call | |
6d0060f6 | 952 | */ |
3f8e0aae | 953 | ret = do_tcp_sendpages(ssk, page, offset, psize, |
72511aab | 954 | msg->msg_flags | MSG_SENDPAGE_NOTLAST | MSG_DONTWAIT); |
35759383 | 955 | if (ret <= 0) { |
b3b2854d FW |
956 | if (!retransmission) |
957 | iov_iter_revert(&msg->msg_iter, psize); | |
6d0060f6 | 958 | return ret; |
35759383 | 959 | } |
18b683bf PA |
960 | |
961 | frag_truesize += ret; | |
3f8e0aae PA |
962 | if (!retransmission) { |
963 | if (unlikely(ret < psize)) | |
964 | iov_iter_revert(&msg->msg_iter, psize - ret); | |
6d0060f6 | 965 | |
3f8e0aae PA |
966 | /* send successful, keep track of sent data for mptcp-level |
967 | * retransmission | |
968 | */ | |
969 | dfrag->data_len += ret; | |
970 | if (!dfrag_collapsed) { | |
971 | get_page(dfrag->page); | |
972 | list_add_tail(&dfrag->list, &msk->rtx_queue); | |
973 | sk_wmem_queued_add(sk, frag_truesize); | |
974 | } else { | |
975 | sk_wmem_queued_add(sk, ret); | |
976 | } | |
18b683bf | 977 | |
3f8e0aae PA |
978 | /* charge data on mptcp rtx queue to the master socket |
979 | * Note: we charge such data both to sk and ssk | |
980 | */ | |
981 | sk->sk_forward_alloc -= frag_truesize; | |
982 | } | |
d027236c | 983 | |
57040755 PA |
984 | /* if the tail skb extension is still the cached one, collapsing |
985 | * really happened. Note: we can't check for 'same skb' as the sk_buff | |
986 | * hdr on tail can be transmitted, freed and re-allocated by the | |
987 | * do_tcp_sendpages() call | |
988 | */ | |
989 | tail = tcp_write_queue_tail(ssk); | |
990 | if (mpext && tail && mpext == skb_ext_find(tail, SKB_EXT_MPTCP)) { | |
991 | WARN_ON_ONCE(!can_collapse); | |
992 | mpext->data_len += ret; | |
993 | goto out; | |
994 | } | |
995 | ||
6d0060f6 MM |
996 | skb = tcp_write_queue_tail(ssk); |
997 | mpext = __skb_ext_set(skb, SKB_EXT_MPTCP, msk->cached_ext); | |
998 | msk->cached_ext = NULL; | |
999 | ||
1000 | memset(mpext, 0, sizeof(*mpext)); | |
3f8e0aae | 1001 | mpext->data_seq = *write_seq; |
6d0060f6 MM |
1002 | mpext->subflow_seq = mptcp_subflow_ctx(ssk)->rel_write_seq; |
1003 | mpext->data_len = ret; | |
1004 | mpext->use_map = 1; | |
1005 | mpext->dsn64 = 1; | |
1006 | ||
1007 | pr_debug("data_seq=%llu subflow_seq=%u data_len=%u dsn64=%d", | |
1008 | mpext->data_seq, mpext->subflow_seq, mpext->data_len, | |
1009 | mpext->dsn64); | |
1010 | ||
57040755 | 1011 | out: |
3f8e0aae PA |
1012 | if (!retransmission) |
1013 | pfrag->offset += frag_truesize; | |
721e9089 | 1014 | WRITE_ONCE(*write_seq, *write_seq + ret); |
6d0060f6 MM |
1015 | mptcp_subflow_ctx(ssk)->rel_write_seq += ret; |
1016 | ||
6d0060f6 MM |
1017 | return ret; |
1018 | } | |
1019 | ||
63561a40 | 1020 | static void mptcp_nospace(struct mptcp_sock *msk) |
a0e17064 | 1021 | { |
63561a40 PA |
1022 | struct mptcp_subflow_context *subflow; |
1023 | ||
a0e17064 FW |
1024 | clear_bit(MPTCP_SEND_SPACE, &msk->flags); |
1025 | smp_mb__after_atomic(); /* msk->flags is changed by write_space cb */ | |
1026 | ||
63561a40 PA |
1027 | mptcp_for_each_subflow(msk, subflow) { |
1028 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
1029 | struct socket *sock = READ_ONCE(ssk->sk_socket); | |
1030 | ||
1031 | /* enables ssk->write_space() callbacks */ | |
1032 | if (sock) | |
1033 | set_bit(SOCK_NOSPACE, &sock->flags); | |
1034 | } | |
a0e17064 FW |
1035 | } |
1036 | ||
d5f49190 PA |
1037 | static bool mptcp_subflow_active(struct mptcp_subflow_context *subflow) |
1038 | { | |
1039 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
1040 | ||
1041 | /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ | |
1042 | if (subflow->request_join && !subflow->fully_established) | |
1043 | return false; | |
1044 | ||
1045 | /* only send if our side has not closed yet */ | |
1046 | return ((1 << ssk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); | |
1047 | } | |
1048 | ||
1049 | #define MPTCP_SEND_BURST_SIZE ((1 << 16) - \ | |
1050 | sizeof(struct tcphdr) - \ | |
1051 | MAX_TCP_OPTION_SPACE - \ | |
1052 | sizeof(struct ipv6hdr) - \ | |
1053 | sizeof(struct frag_hdr)) | |
1054 | ||
1055 | struct subflow_send_info { | |
1056 | struct sock *ssk; | |
1057 | u64 ratio; | |
1058 | }; | |
1059 | ||
da51aef5 PA |
1060 | static struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk, |
1061 | u32 *sndbuf) | |
f296234c | 1062 | { |
d5f49190 | 1063 | struct subflow_send_info send_info[2]; |
f296234c | 1064 | struct mptcp_subflow_context *subflow; |
d5f49190 PA |
1065 | int i, nr_active = 0; |
1066 | struct sock *ssk; | |
1067 | u64 ratio; | |
1068 | u32 pace; | |
f296234c | 1069 | |
d5f49190 | 1070 | sock_owned_by_me((struct sock *)msk); |
f296234c | 1071 | |
da51aef5 | 1072 | *sndbuf = 0; |
149f7c71 FW |
1073 | if (!mptcp_ext_cache_refill(msk)) |
1074 | return NULL; | |
1075 | ||
d5f49190 PA |
1076 | if (__mptcp_check_fallback(msk)) { |
1077 | if (!msk->first) | |
f296234c | 1078 | return NULL; |
d5f49190 PA |
1079 | *sndbuf = msk->first->sk_sndbuf; |
1080 | return sk_stream_memory_free(msk->first) ? msk->first : NULL; | |
1081 | } | |
1082 | ||
1083 | /* re-use last subflow, if the burst allow that */ | |
1084 | if (msk->last_snd && msk->snd_burst > 0 && | |
1085 | sk_stream_memory_free(msk->last_snd) && | |
1086 | mptcp_subflow_active(mptcp_subflow_ctx(msk->last_snd))) { | |
1087 | mptcp_for_each_subflow(msk, subflow) { | |
1088 | ssk = mptcp_subflow_tcp_sock(subflow); | |
1089 | *sndbuf = max(tcp_sk(ssk)->snd_wnd, *sndbuf); | |
f296234c | 1090 | } |
d5f49190 PA |
1091 | return msk->last_snd; |
1092 | } | |
f296234c | 1093 | |
d5f49190 PA |
1094 | /* pick the subflow with the lower wmem/wspace ratio */ |
1095 | for (i = 0; i < 2; ++i) { | |
1096 | send_info[i].ssk = NULL; | |
1097 | send_info[i].ratio = -1; | |
1098 | } | |
1099 | mptcp_for_each_subflow(msk, subflow) { | |
1100 | ssk = mptcp_subflow_tcp_sock(subflow); | |
1101 | if (!mptcp_subflow_active(subflow)) | |
1102 | continue; | |
1103 | ||
1104 | nr_active += !subflow->backup; | |
da51aef5 | 1105 | *sndbuf = max(tcp_sk(ssk)->snd_wnd, *sndbuf); |
d5f49190 PA |
1106 | if (!sk_stream_memory_free(subflow->tcp_sock)) |
1107 | continue; | |
f296234c | 1108 | |
d5f49190 PA |
1109 | pace = READ_ONCE(ssk->sk_pacing_rate); |
1110 | if (!pace) | |
f296234c | 1111 | continue; |
f296234c | 1112 | |
d5f49190 PA |
1113 | ratio = div_u64((u64)READ_ONCE(ssk->sk_wmem_queued) << 32, |
1114 | pace); | |
1115 | if (ratio < send_info[subflow->backup].ratio) { | |
1116 | send_info[subflow->backup].ssk = ssk; | |
1117 | send_info[subflow->backup].ratio = ratio; | |
1118 | } | |
f296234c PK |
1119 | } |
1120 | ||
d5f49190 PA |
1121 | pr_debug("msk=%p nr_active=%d ssk=%p:%lld backup=%p:%lld", |
1122 | msk, nr_active, send_info[0].ssk, send_info[0].ratio, | |
1123 | send_info[1].ssk, send_info[1].ratio); | |
1124 | ||
1125 | /* pick the best backup if no other subflow is active */ | |
1126 | if (!nr_active) | |
1127 | send_info[0].ssk = send_info[1].ssk; | |
1128 | ||
1129 | if (send_info[0].ssk) { | |
1130 | msk->last_snd = send_info[0].ssk; | |
1131 | msk->snd_burst = min_t(int, MPTCP_SEND_BURST_SIZE, | |
1132 | sk_stream_wspace(msk->last_snd)); | |
1133 | return msk->last_snd; | |
1134 | } | |
1135 | return NULL; | |
f296234c PK |
1136 | } |
1137 | ||
63561a40 | 1138 | static void ssk_check_wmem(struct mptcp_sock *msk) |
1891c4a0 | 1139 | { |
63561a40 PA |
1140 | if (unlikely(!mptcp_is_writeable(msk))) |
1141 | mptcp_nospace(msk); | |
1891c4a0 FW |
1142 | } |
1143 | ||
f870fa0b MM |
1144 | static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) |
1145 | { | |
57040755 | 1146 | int mss_now = 0, size_goal = 0, ret = 0; |
f870fa0b | 1147 | struct mptcp_sock *msk = mptcp_sk(sk); |
17091708 | 1148 | struct page_frag *pfrag; |
6d0060f6 | 1149 | size_t copied = 0; |
cec37a6e | 1150 | struct sock *ssk; |
da51aef5 | 1151 | u32 sndbuf; |
72511aab | 1152 | bool tx_ok; |
6d0060f6 | 1153 | long timeo; |
f870fa0b MM |
1154 | |
1155 | if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL)) | |
1156 | return -EOPNOTSUPP; | |
1157 | ||
cec37a6e | 1158 | lock_sock(sk); |
1954b860 MM |
1159 | |
1160 | timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); | |
1161 | ||
1162 | if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { | |
1163 | ret = sk_stream_wait_connect(sk, &timeo); | |
1164 | if (ret) | |
1165 | goto out; | |
1166 | } | |
1167 | ||
17091708 | 1168 | pfrag = sk_page_frag(sk); |
72511aab | 1169 | restart: |
18b683bf PA |
1170 | mptcp_clean_una(sk); |
1171 | ||
57baaf28 MM |
1172 | if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) { |
1173 | ret = -EPIPE; | |
1174 | goto out; | |
1175 | } | |
1176 | ||
ec3edaa7 | 1177 | __mptcp_flush_join_list(msk); |
da51aef5 | 1178 | ssk = mptcp_subflow_get_send(msk, &sndbuf); |
17091708 FW |
1179 | while (!sk_stream_memory_free(sk) || |
1180 | !ssk || | |
1181 | !mptcp_page_frag_refill(ssk, pfrag)) { | |
fb529e62 FW |
1182 | if (ssk) { |
1183 | /* make sure retransmit timer is | |
1184 | * running before we wait for memory. | |
1185 | * | |
1186 | * The retransmit timer might be needed | |
1187 | * to make the peer send an up-to-date | |
1188 | * MPTCP Ack. | |
1189 | */ | |
1190 | mptcp_set_timeout(sk, ssk); | |
1191 | if (!mptcp_timer_pending(sk)) | |
1192 | mptcp_reset_timer(sk); | |
1193 | } | |
1194 | ||
63561a40 | 1195 | mptcp_nospace(msk); |
f296234c PK |
1196 | ret = sk_stream_wait_memory(sk, &timeo); |
1197 | if (ret) | |
1198 | goto out; | |
1199 | ||
18b683bf PA |
1200 | mptcp_clean_una(sk); |
1201 | ||
da51aef5 | 1202 | ssk = mptcp_subflow_get_send(msk, &sndbuf); |
f296234c PK |
1203 | if (list_empty(&msk->conn_list)) { |
1204 | ret = -ENOTCONN; | |
1205 | goto out; | |
1206 | } | |
cec37a6e PK |
1207 | } |
1208 | ||
da51aef5 PA |
1209 | /* do auto tuning */ |
1210 | if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK) && | |
1211 | sndbuf > READ_ONCE(sk->sk_sndbuf)) | |
1212 | WRITE_ONCE(sk->sk_sndbuf, sndbuf); | |
1213 | ||
6d0060f6 | 1214 | pr_debug("conn_list->subflow=%p", ssk); |
cec37a6e | 1215 | |
6d0060f6 | 1216 | lock_sock(ssk); |
72511aab FW |
1217 | tx_ok = msg_data_left(msg); |
1218 | while (tx_ok) { | |
3f8e0aae | 1219 | ret = mptcp_sendmsg_frag(sk, ssk, msg, NULL, &timeo, &mss_now, |
57040755 | 1220 | &size_goal); |
72511aab FW |
1221 | if (ret < 0) { |
1222 | if (ret == -EAGAIN && timeo > 0) { | |
1223 | mptcp_set_timeout(sk, ssk); | |
1224 | release_sock(ssk); | |
1225 | goto restart; | |
1226 | } | |
6d0060f6 | 1227 | break; |
72511aab | 1228 | } |
6d0060f6 | 1229 | |
d5f49190 PA |
1230 | /* burst can be negative, we will try move to the next subflow |
1231 | * at selection time, if possible. | |
1232 | */ | |
1233 | msk->snd_burst -= ret; | |
6d0060f6 | 1234 | copied += ret; |
fb529e62 | 1235 | |
72511aab FW |
1236 | tx_ok = msg_data_left(msg); |
1237 | if (!tx_ok) | |
1238 | break; | |
1239 | ||
149f7c71 | 1240 | if (!sk_stream_memory_free(ssk) || |
17091708 | 1241 | !mptcp_page_frag_refill(ssk, pfrag) || |
149f7c71 | 1242 | !mptcp_ext_cache_refill(msk)) { |
72511aab FW |
1243 | tcp_push(ssk, msg->msg_flags, mss_now, |
1244 | tcp_sk(ssk)->nonagle, size_goal); | |
1245 | mptcp_set_timeout(sk, ssk); | |
1246 | release_sock(ssk); | |
1247 | goto restart; | |
1248 | } | |
1249 | ||
fb529e62 FW |
1250 | /* memory is charged to mptcp level socket as well, i.e. |
1251 | * if msg is very large, mptcp socket may run out of buffer | |
1252 | * space. mptcp_clean_una() will release data that has | |
1253 | * been acked at mptcp level in the mean time, so there is | |
1254 | * a good chance we can continue sending data right away. | |
72511aab FW |
1255 | * |
1256 | * Normally, when the tcp subflow can accept more data, then | |
1257 | * so can the MPTCP socket. However, we need to cope with | |
1258 | * peers that might lag behind in their MPTCP-level | |
1259 | * acknowledgements, i.e. data might have been acked at | |
1260 | * tcp level only. So, we must also check the MPTCP socket | |
1261 | * limits before we send more data. | |
fb529e62 FW |
1262 | */ |
1263 | if (unlikely(!sk_stream_memory_free(sk))) { | |
1264 | tcp_push(ssk, msg->msg_flags, mss_now, | |
1265 | tcp_sk(ssk)->nonagle, size_goal); | |
1266 | mptcp_clean_una(sk); | |
1267 | if (!sk_stream_memory_free(sk)) { | |
1268 | /* can't send more for now, need to wait for | |
1269 | * MPTCP-level ACKs from peer. | |
1270 | * | |
1271 | * Wakeup will happen via mptcp_clean_una(). | |
1272 | */ | |
1273 | mptcp_set_timeout(sk, ssk); | |
1274 | release_sock(ssk); | |
1cec170d | 1275 | goto restart; |
fb529e62 FW |
1276 | } |
1277 | } | |
6d0060f6 MM |
1278 | } |
1279 | ||
b51f9b80 | 1280 | mptcp_set_timeout(sk, ssk); |
57040755 | 1281 | if (copied) { |
57040755 PA |
1282 | tcp_push(ssk, msg->msg_flags, mss_now, tcp_sk(ssk)->nonagle, |
1283 | size_goal); | |
b51f9b80 PA |
1284 | |
1285 | /* start the timer, if it's not pending */ | |
1286 | if (!mptcp_timer_pending(sk)) | |
1287 | mptcp_reset_timer(sk); | |
57040755 | 1288 | } |
6d0060f6 MM |
1289 | |
1290 | release_sock(ssk); | |
1954b860 | 1291 | out: |
63561a40 | 1292 | ssk_check_wmem(msk); |
cec37a6e | 1293 | release_sock(sk); |
8555c6bf | 1294 | return copied ? : ret; |
f870fa0b MM |
1295 | } |
1296 | ||
7a6a6cbc PA |
1297 | static void mptcp_wait_data(struct sock *sk, long *timeo) |
1298 | { | |
1299 | DEFINE_WAIT_FUNC(wait, woken_wake_function); | |
1300 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1301 | ||
1302 | add_wait_queue(sk_sleep(sk), &wait); | |
1303 | sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); | |
1304 | ||
1305 | sk_wait_event(sk, timeo, | |
1306 | test_and_clear_bit(MPTCP_DATA_READY, &msk->flags), &wait); | |
1307 | ||
1308 | sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); | |
1309 | remove_wait_queue(sk_sleep(sk), &wait); | |
1310 | } | |
1311 | ||
6771bfd9 FW |
1312 | static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk, |
1313 | struct msghdr *msg, | |
1314 | size_t len) | |
1315 | { | |
1316 | struct sock *sk = (struct sock *)msk; | |
1317 | struct sk_buff *skb; | |
1318 | int copied = 0; | |
1319 | ||
1320 | while ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) { | |
1321 | u32 offset = MPTCP_SKB_CB(skb)->offset; | |
1322 | u32 data_len = skb->len - offset; | |
1323 | u32 count = min_t(size_t, len - copied, data_len); | |
1324 | int err; | |
1325 | ||
1326 | err = skb_copy_datagram_msg(skb, offset, msg, count); | |
1327 | if (unlikely(err < 0)) { | |
1328 | if (!copied) | |
1329 | return err; | |
1330 | break; | |
1331 | } | |
1332 | ||
1333 | copied += count; | |
1334 | ||
1335 | if (count < data_len) { | |
1336 | MPTCP_SKB_CB(skb)->offset += count; | |
1337 | break; | |
1338 | } | |
1339 | ||
1340 | __skb_unlink(skb, &sk->sk_receive_queue); | |
1341 | __kfree_skb(skb); | |
1342 | ||
1343 | if (copied >= len) | |
1344 | break; | |
1345 | } | |
1346 | ||
1347 | return copied; | |
1348 | } | |
1349 | ||
a6b118fe FW |
1350 | /* receive buffer autotuning. See tcp_rcv_space_adjust for more information. |
1351 | * | |
1352 | * Only difference: Use highest rtt estimate of the subflows in use. | |
1353 | */ | |
1354 | static void mptcp_rcv_space_adjust(struct mptcp_sock *msk, int copied) | |
1355 | { | |
1356 | struct mptcp_subflow_context *subflow; | |
1357 | struct sock *sk = (struct sock *)msk; | |
1358 | u32 time, advmss = 1; | |
1359 | u64 rtt_us, mstamp; | |
1360 | ||
1361 | sock_owned_by_me(sk); | |
1362 | ||
1363 | if (copied <= 0) | |
1364 | return; | |
1365 | ||
1366 | msk->rcvq_space.copied += copied; | |
1367 | ||
1368 | mstamp = div_u64(tcp_clock_ns(), NSEC_PER_USEC); | |
1369 | time = tcp_stamp_us_delta(mstamp, msk->rcvq_space.time); | |
1370 | ||
1371 | rtt_us = msk->rcvq_space.rtt_us; | |
1372 | if (rtt_us && time < (rtt_us >> 3)) | |
1373 | return; | |
1374 | ||
1375 | rtt_us = 0; | |
1376 | mptcp_for_each_subflow(msk, subflow) { | |
1377 | const struct tcp_sock *tp; | |
1378 | u64 sf_rtt_us; | |
1379 | u32 sf_advmss; | |
1380 | ||
1381 | tp = tcp_sk(mptcp_subflow_tcp_sock(subflow)); | |
1382 | ||
1383 | sf_rtt_us = READ_ONCE(tp->rcv_rtt_est.rtt_us); | |
1384 | sf_advmss = READ_ONCE(tp->advmss); | |
1385 | ||
1386 | rtt_us = max(sf_rtt_us, rtt_us); | |
1387 | advmss = max(sf_advmss, advmss); | |
1388 | } | |
1389 | ||
1390 | msk->rcvq_space.rtt_us = rtt_us; | |
1391 | if (time < (rtt_us >> 3) || rtt_us == 0) | |
1392 | return; | |
1393 | ||
1394 | if (msk->rcvq_space.copied <= msk->rcvq_space.space) | |
1395 | goto new_measure; | |
1396 | ||
1397 | if (sock_net(sk)->ipv4.sysctl_tcp_moderate_rcvbuf && | |
1398 | !(sk->sk_userlocks & SOCK_RCVBUF_LOCK)) { | |
1399 | int rcvmem, rcvbuf; | |
1400 | u64 rcvwin, grow; | |
1401 | ||
1402 | rcvwin = ((u64)msk->rcvq_space.copied << 1) + 16 * advmss; | |
1403 | ||
1404 | grow = rcvwin * (msk->rcvq_space.copied - msk->rcvq_space.space); | |
1405 | ||
1406 | do_div(grow, msk->rcvq_space.space); | |
1407 | rcvwin += (grow << 1); | |
1408 | ||
1409 | rcvmem = SKB_TRUESIZE(advmss + MAX_TCP_HEADER); | |
1410 | while (tcp_win_from_space(sk, rcvmem) < advmss) | |
1411 | rcvmem += 128; | |
1412 | ||
1413 | do_div(rcvwin, advmss); | |
1414 | rcvbuf = min_t(u64, rcvwin * rcvmem, | |
1415 | sock_net(sk)->ipv4.sysctl_tcp_rmem[2]); | |
1416 | ||
1417 | if (rcvbuf > sk->sk_rcvbuf) { | |
1418 | u32 window_clamp; | |
1419 | ||
1420 | window_clamp = tcp_win_from_space(sk, rcvbuf); | |
1421 | WRITE_ONCE(sk->sk_rcvbuf, rcvbuf); | |
1422 | ||
1423 | /* Make subflows follow along. If we do not do this, we | |
1424 | * get drops at subflow level if skbs can't be moved to | |
1425 | * the mptcp rx queue fast enough (announced rcv_win can | |
1426 | * exceed ssk->sk_rcvbuf). | |
1427 | */ | |
1428 | mptcp_for_each_subflow(msk, subflow) { | |
1429 | struct sock *ssk; | |
c76c6956 | 1430 | bool slow; |
a6b118fe FW |
1431 | |
1432 | ssk = mptcp_subflow_tcp_sock(subflow); | |
c76c6956 | 1433 | slow = lock_sock_fast(ssk); |
a6b118fe FW |
1434 | WRITE_ONCE(ssk->sk_rcvbuf, rcvbuf); |
1435 | tcp_sk(ssk)->window_clamp = window_clamp; | |
c76c6956 PA |
1436 | tcp_cleanup_rbuf(ssk, 1); |
1437 | unlock_sock_fast(ssk, slow); | |
a6b118fe FW |
1438 | } |
1439 | } | |
1440 | } | |
1441 | ||
1442 | msk->rcvq_space.space = msk->rcvq_space.copied; | |
1443 | new_measure: | |
1444 | msk->rcvq_space.copied = 0; | |
1445 | msk->rcvq_space.time = mstamp; | |
1446 | } | |
1447 | ||
6771bfd9 FW |
1448 | static bool __mptcp_move_skbs(struct mptcp_sock *msk) |
1449 | { | |
1450 | unsigned int moved = 0; | |
1451 | bool done; | |
1452 | ||
d5f49190 PA |
1453 | /* avoid looping forever below on racing close */ |
1454 | if (((struct sock *)msk)->sk_state == TCP_CLOSE) | |
1455 | return false; | |
1456 | ||
1457 | __mptcp_flush_join_list(msk); | |
6771bfd9 FW |
1458 | do { |
1459 | struct sock *ssk = mptcp_subflow_recv_lookup(msk); | |
1460 | ||
1461 | if (!ssk) | |
1462 | break; | |
1463 | ||
1464 | lock_sock(ssk); | |
1465 | done = __mptcp_move_skbs_from_subflow(msk, ssk, &moved); | |
1466 | release_sock(ssk); | |
1467 | } while (!done); | |
1468 | ||
ab174ad8 PA |
1469 | if (mptcp_ofo_queue(msk) || moved > 0) { |
1470 | mptcp_check_data_fin((struct sock *)msk); | |
1471 | return true; | |
1472 | } | |
1473 | return false; | |
6771bfd9 FW |
1474 | } |
1475 | ||
f870fa0b MM |
1476 | static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, |
1477 | int nonblock, int flags, int *addr_len) | |
1478 | { | |
1479 | struct mptcp_sock *msk = mptcp_sk(sk); | |
cec37a6e | 1480 | int copied = 0; |
7a6a6cbc PA |
1481 | int target; |
1482 | long timeo; | |
f870fa0b MM |
1483 | |
1484 | if (msg->msg_flags & ~(MSG_WAITALL | MSG_DONTWAIT)) | |
1485 | return -EOPNOTSUPP; | |
1486 | ||
cec37a6e | 1487 | lock_sock(sk); |
7a6a6cbc PA |
1488 | timeo = sock_rcvtimeo(sk, nonblock); |
1489 | ||
1490 | len = min_t(size_t, len, INT_MAX); | |
1491 | target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); | |
ec3edaa7 | 1492 | __mptcp_flush_join_list(msk); |
7a6a6cbc | 1493 | |
6771bfd9 | 1494 | while (len > (size_t)copied) { |
7a6a6cbc PA |
1495 | int bytes_read; |
1496 | ||
6771bfd9 FW |
1497 | bytes_read = __mptcp_recvmsg_mskq(msk, msg, len - copied); |
1498 | if (unlikely(bytes_read < 0)) { | |
1499 | if (!copied) | |
1500 | copied = bytes_read; | |
1501 | goto out_err; | |
1502 | } | |
7a6a6cbc | 1503 | |
6771bfd9 | 1504 | copied += bytes_read; |
7a6a6cbc | 1505 | |
6771bfd9 FW |
1506 | if (skb_queue_empty(&sk->sk_receive_queue) && |
1507 | __mptcp_move_skbs(msk)) | |
1508 | continue; | |
7a6a6cbc PA |
1509 | |
1510 | /* only the master socket status is relevant here. The exit | |
1511 | * conditions mirror closely tcp_recvmsg() | |
1512 | */ | |
1513 | if (copied >= target) | |
1514 | break; | |
1515 | ||
1516 | if (copied) { | |
1517 | if (sk->sk_err || | |
1518 | sk->sk_state == TCP_CLOSE || | |
1519 | (sk->sk_shutdown & RCV_SHUTDOWN) || | |
1520 | !timeo || | |
1521 | signal_pending(current)) | |
1522 | break; | |
1523 | } else { | |
1524 | if (sk->sk_err) { | |
1525 | copied = sock_error(sk); | |
1526 | break; | |
1527 | } | |
1528 | ||
5969856a PA |
1529 | if (test_and_clear_bit(MPTCP_WORK_EOF, &msk->flags)) |
1530 | mptcp_check_for_eof(msk); | |
1531 | ||
7a6a6cbc PA |
1532 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
1533 | break; | |
1534 | ||
1535 | if (sk->sk_state == TCP_CLOSE) { | |
1536 | copied = -ENOTCONN; | |
1537 | break; | |
1538 | } | |
1539 | ||
1540 | if (!timeo) { | |
1541 | copied = -EAGAIN; | |
1542 | break; | |
1543 | } | |
1544 | ||
1545 | if (signal_pending(current)) { | |
1546 | copied = sock_intr_errno(timeo); | |
1547 | break; | |
1548 | } | |
1549 | } | |
1550 | ||
1551 | pr_debug("block timeout %ld", timeo); | |
7a6a6cbc | 1552 | mptcp_wait_data(sk, &timeo); |
cec37a6e PK |
1553 | } |
1554 | ||
6771bfd9 FW |
1555 | if (skb_queue_empty(&sk->sk_receive_queue)) { |
1556 | /* entire backlog drained, clear DATA_READY. */ | |
7a6a6cbc | 1557 | clear_bit(MPTCP_DATA_READY, &msk->flags); |
cec37a6e | 1558 | |
6771bfd9 FW |
1559 | /* .. race-breaker: ssk might have gotten new data |
1560 | * after last __mptcp_move_skbs() returned false. | |
7a6a6cbc | 1561 | */ |
6771bfd9 | 1562 | if (unlikely(__mptcp_move_skbs(msk))) |
7a6a6cbc | 1563 | set_bit(MPTCP_DATA_READY, &msk->flags); |
6771bfd9 FW |
1564 | } else if (unlikely(!test_bit(MPTCP_DATA_READY, &msk->flags))) { |
1565 | /* data to read but mptcp_wait_data() cleared DATA_READY */ | |
1566 | set_bit(MPTCP_DATA_READY, &msk->flags); | |
7a6a6cbc | 1567 | } |
6771bfd9 | 1568 | out_err: |
6719331c PA |
1569 | pr_debug("msk=%p data_ready=%d rx queue empty=%d copied=%d", |
1570 | msk, test_bit(MPTCP_DATA_READY, &msk->flags), | |
1571 | skb_queue_empty(&sk->sk_receive_queue), copied); | |
a6b118fe FW |
1572 | mptcp_rcv_space_adjust(msk, copied); |
1573 | ||
7a6a6cbc | 1574 | release_sock(sk); |
cec37a6e PK |
1575 | return copied; |
1576 | } | |
1577 | ||
b51f9b80 PA |
1578 | static void mptcp_retransmit_handler(struct sock *sk) |
1579 | { | |
1580 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1581 | ||
c7529392 | 1582 | if (atomic64_read(&msk->snd_una) == READ_ONCE(msk->write_seq)) { |
b51f9b80 | 1583 | mptcp_stop_timer(sk); |
3b1d6210 PA |
1584 | } else { |
1585 | set_bit(MPTCP_WORK_RTX, &msk->flags); | |
1586 | if (schedule_work(&msk->work)) | |
1587 | sock_hold(sk); | |
1588 | } | |
b51f9b80 PA |
1589 | } |
1590 | ||
1591 | static void mptcp_retransmit_timer(struct timer_list *t) | |
1592 | { | |
1593 | struct inet_connection_sock *icsk = from_timer(icsk, t, | |
1594 | icsk_retransmit_timer); | |
1595 | struct sock *sk = &icsk->icsk_inet.sk; | |
1596 | ||
1597 | bh_lock_sock(sk); | |
1598 | if (!sock_owned_by_user(sk)) { | |
1599 | mptcp_retransmit_handler(sk); | |
1600 | } else { | |
1601 | /* delegate our work to tcp_release_cb() */ | |
1602 | if (!test_and_set_bit(TCP_WRITE_TIMER_DEFERRED, | |
1603 | &sk->sk_tsq_flags)) | |
1604 | sock_hold(sk); | |
1605 | } | |
1606 | bh_unlock_sock(sk); | |
1607 | sock_put(sk); | |
1608 | } | |
1609 | ||
3b1d6210 PA |
1610 | /* Find an idle subflow. Return NULL if there is unacked data at tcp |
1611 | * level. | |
1612 | * | |
1613 | * A backup subflow is returned only if that is the only kind available. | |
1614 | */ | |
1615 | static struct sock *mptcp_subflow_get_retrans(const struct mptcp_sock *msk) | |
1616 | { | |
1617 | struct mptcp_subflow_context *subflow; | |
1618 | struct sock *backup = NULL; | |
1619 | ||
1620 | sock_owned_by_me((const struct sock *)msk); | |
1621 | ||
d5f49190 PA |
1622 | if (__mptcp_check_fallback(msk)) |
1623 | return msk->first; | |
1624 | ||
3b1d6210 PA |
1625 | mptcp_for_each_subflow(msk, subflow) { |
1626 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
1627 | ||
d5f49190 PA |
1628 | if (!mptcp_subflow_active(subflow)) |
1629 | continue; | |
1630 | ||
3b1d6210 PA |
1631 | /* still data outstanding at TCP level? Don't retransmit. */ |
1632 | if (!tcp_write_queue_empty(ssk)) | |
1633 | return NULL; | |
1634 | ||
1635 | if (subflow->backup) { | |
1636 | if (!backup) | |
1637 | backup = ssk; | |
1638 | continue; | |
1639 | } | |
1640 | ||
1641 | return ssk; | |
1642 | } | |
1643 | ||
1644 | return backup; | |
1645 | } | |
1646 | ||
cec37a6e PK |
1647 | /* subflow sockets can be either outgoing (connect) or incoming |
1648 | * (accept). | |
1649 | * | |
1650 | * Outgoing subflows use in-kernel sockets. | |
1651 | * Incoming subflows do not have their own 'struct socket' allocated, | |
1652 | * so we need to use tcp_close() after detaching them from the mptcp | |
1653 | * parent socket. | |
1654 | */ | |
1655 | static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, | |
1656 | struct mptcp_subflow_context *subflow, | |
1657 | long timeout) | |
1658 | { | |
1659 | struct socket *sock = READ_ONCE(ssk->sk_socket); | |
1660 | ||
1661 | list_del(&subflow->node); | |
1662 | ||
1663 | if (sock && sock != sk->sk_socket) { | |
1664 | /* outgoing subflow */ | |
1665 | sock_release(sock); | |
1666 | } else { | |
1667 | /* incoming subflow */ | |
1668 | tcp_close(ssk, timeout); | |
1669 | } | |
f870fa0b MM |
1670 | } |
1671 | ||
dc24f8b4 PA |
1672 | static unsigned int mptcp_sync_mss(struct sock *sk, u32 pmtu) |
1673 | { | |
1674 | return 0; | |
1675 | } | |
1676 | ||
b416268b FW |
1677 | static void pm_work(struct mptcp_sock *msk) |
1678 | { | |
1679 | struct mptcp_pm_data *pm = &msk->pm; | |
1680 | ||
1681 | spin_lock_bh(&msk->pm.lock); | |
1682 | ||
1683 | pr_debug("msk=%p status=%x", msk, pm->status); | |
1684 | if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { | |
1685 | pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); | |
1686 | mptcp_pm_nl_add_addr_received(msk); | |
1687 | } | |
1688 | if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { | |
1689 | pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); | |
1690 | mptcp_pm_nl_fully_established(msk); | |
1691 | } | |
1692 | if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { | |
1693 | pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); | |
1694 | mptcp_pm_nl_subflow_established(msk); | |
1695 | } | |
1696 | ||
1697 | spin_unlock_bh(&msk->pm.lock); | |
1698 | } | |
1699 | ||
80992017 PA |
1700 | static void mptcp_worker(struct work_struct *work) |
1701 | { | |
1702 | struct mptcp_sock *msk = container_of(work, struct mptcp_sock, work); | |
3b1d6210 | 1703 | struct sock *ssk, *sk = &msk->sk.icsk_inet.sk; |
149f7c71 | 1704 | int orig_len, orig_offset, mss_now = 0, size_goal = 0; |
3b1d6210 PA |
1705 | struct mptcp_data_frag *dfrag; |
1706 | u64 orig_write_seq; | |
1707 | size_t copied = 0; | |
b3b2854d FW |
1708 | struct msghdr msg = { |
1709 | .msg_flags = MSG_DONTWAIT, | |
1710 | }; | |
3b1d6210 | 1711 | long timeo = 0; |
80992017 PA |
1712 | |
1713 | lock_sock(sk); | |
3b1d6210 | 1714 | mptcp_clean_una(sk); |
43b54c6e | 1715 | mptcp_check_data_fin_ack(sk); |
ec3edaa7 | 1716 | __mptcp_flush_join_list(msk); |
6771bfd9 | 1717 | __mptcp_move_skbs(msk); |
3b1d6210 | 1718 | |
b416268b FW |
1719 | if (msk->pm.status) |
1720 | pm_work(msk); | |
1721 | ||
59832e24 FW |
1722 | if (test_and_clear_bit(MPTCP_WORK_EOF, &msk->flags)) |
1723 | mptcp_check_for_eof(msk); | |
1724 | ||
43b54c6e MM |
1725 | mptcp_check_data_fin(sk); |
1726 | ||
3b1d6210 PA |
1727 | if (!test_and_clear_bit(MPTCP_WORK_RTX, &msk->flags)) |
1728 | goto unlock; | |
1729 | ||
1730 | dfrag = mptcp_rtx_head(sk); | |
1731 | if (!dfrag) | |
1732 | goto unlock; | |
1733 | ||
149f7c71 FW |
1734 | if (!mptcp_ext_cache_refill(msk)) |
1735 | goto reset_unlock; | |
1736 | ||
3b1d6210 PA |
1737 | ssk = mptcp_subflow_get_retrans(msk); |
1738 | if (!ssk) | |
1739 | goto reset_unlock; | |
1740 | ||
1741 | lock_sock(ssk); | |
1742 | ||
3b1d6210 PA |
1743 | orig_len = dfrag->data_len; |
1744 | orig_offset = dfrag->offset; | |
1745 | orig_write_seq = dfrag->data_seq; | |
1746 | while (dfrag->data_len > 0) { | |
149f7c71 FW |
1747 | int ret = mptcp_sendmsg_frag(sk, ssk, &msg, dfrag, &timeo, |
1748 | &mss_now, &size_goal); | |
3b1d6210 PA |
1749 | if (ret < 0) |
1750 | break; | |
1751 | ||
fc518953 | 1752 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RETRANSSEGS); |
3b1d6210 PA |
1753 | copied += ret; |
1754 | dfrag->data_len -= ret; | |
1755 | dfrag->offset += ret; | |
149f7c71 FW |
1756 | |
1757 | if (!mptcp_ext_cache_refill(msk)) | |
1758 | break; | |
3b1d6210 PA |
1759 | } |
1760 | if (copied) | |
1761 | tcp_push(ssk, msg.msg_flags, mss_now, tcp_sk(ssk)->nonagle, | |
1762 | size_goal); | |
1763 | ||
1764 | dfrag->data_seq = orig_write_seq; | |
1765 | dfrag->offset = orig_offset; | |
1766 | dfrag->data_len = orig_len; | |
1767 | ||
1768 | mptcp_set_timeout(sk, ssk); | |
1769 | release_sock(ssk); | |
1770 | ||
1771 | reset_unlock: | |
1772 | if (!mptcp_timer_pending(sk)) | |
1773 | mptcp_reset_timer(sk); | |
1774 | ||
1775 | unlock: | |
80992017 PA |
1776 | release_sock(sk); |
1777 | sock_put(sk); | |
1778 | } | |
1779 | ||
784325e9 | 1780 | static int __mptcp_init_sock(struct sock *sk) |
f870fa0b | 1781 | { |
cec37a6e PK |
1782 | struct mptcp_sock *msk = mptcp_sk(sk); |
1783 | ||
ec3edaa7 PK |
1784 | spin_lock_init(&msk->join_list_lock); |
1785 | ||
cec37a6e | 1786 | INIT_LIST_HEAD(&msk->conn_list); |
ec3edaa7 | 1787 | INIT_LIST_HEAD(&msk->join_list); |
18b683bf | 1788 | INIT_LIST_HEAD(&msk->rtx_queue); |
1891c4a0 | 1789 | __set_bit(MPTCP_SEND_SPACE, &msk->flags); |
80992017 | 1790 | INIT_WORK(&msk->work, mptcp_worker); |
ab174ad8 | 1791 | msk->out_of_order_queue = RB_ROOT; |
cec37a6e | 1792 | |
8ab183de | 1793 | msk->first = NULL; |
dc24f8b4 | 1794 | inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss; |
8ab183de | 1795 | |
1b1c7a0e PK |
1796 | mptcp_pm_data_init(msk); |
1797 | ||
b51f9b80 PA |
1798 | /* re-use the csk retrans timer for MPTCP-level retrans */ |
1799 | timer_setup(&msk->sk.icsk_retransmit_timer, mptcp_retransmit_timer, 0); | |
1800 | ||
f870fa0b MM |
1801 | return 0; |
1802 | } | |
1803 | ||
784325e9 MB |
1804 | static int mptcp_init_sock(struct sock *sk) |
1805 | { | |
fc518953 FW |
1806 | struct net *net = sock_net(sk); |
1807 | int ret; | |
18b683bf | 1808 | |
fc518953 FW |
1809 | if (!mptcp_is_enabled(net)) |
1810 | return -ENOPROTOOPT; | |
1811 | ||
1812 | if (unlikely(!net->mib.mptcp_statistics) && !mptcp_mib_alloc(net)) | |
1813 | return -ENOMEM; | |
1814 | ||
1815 | ret = __mptcp_init_sock(sk); | |
18b683bf PA |
1816 | if (ret) |
1817 | return ret; | |
1818 | ||
fa68018d PA |
1819 | ret = __mptcp_socket_create(mptcp_sk(sk)); |
1820 | if (ret) | |
1821 | return ret; | |
1822 | ||
d027236c | 1823 | sk_sockets_allocated_inc(sk); |
a6b118fe | 1824 | sk->sk_rcvbuf = sock_net(sk)->ipv4.sysctl_tcp_rmem[1]; |
da51aef5 | 1825 | sk->sk_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[1]; |
d027236c | 1826 | |
18b683bf PA |
1827 | return 0; |
1828 | } | |
1829 | ||
1830 | static void __mptcp_clear_xmit(struct sock *sk) | |
1831 | { | |
1832 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1833 | struct mptcp_data_frag *dtmp, *dfrag; | |
1834 | ||
b51f9b80 PA |
1835 | sk_stop_timer(sk, &msk->sk.icsk_retransmit_timer); |
1836 | ||
18b683bf | 1837 | list_for_each_entry_safe(dfrag, dtmp, &msk->rtx_queue, list) |
d027236c | 1838 | dfrag_clear(sk, dfrag); |
784325e9 MB |
1839 | } |
1840 | ||
80992017 PA |
1841 | static void mptcp_cancel_work(struct sock *sk) |
1842 | { | |
1843 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1844 | ||
1845 | if (cancel_work_sync(&msk->work)) | |
1846 | sock_put(sk); | |
1847 | } | |
1848 | ||
43b54c6e | 1849 | static void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how) |
21498490 PK |
1850 | { |
1851 | lock_sock(ssk); | |
1852 | ||
1853 | switch (ssk->sk_state) { | |
1854 | case TCP_LISTEN: | |
1855 | if (!(how & RCV_SHUTDOWN)) | |
1856 | break; | |
df561f66 | 1857 | fallthrough; |
21498490 PK |
1858 | case TCP_SYN_SENT: |
1859 | tcp_disconnect(ssk, O_NONBLOCK); | |
1860 | break; | |
1861 | default: | |
43b54c6e MM |
1862 | if (__mptcp_check_fallback(mptcp_sk(sk))) { |
1863 | pr_debug("Fallback"); | |
1864 | ssk->sk_shutdown |= how; | |
1865 | tcp_shutdown(ssk, how); | |
1866 | } else { | |
1867 | pr_debug("Sending DATA_FIN on subflow %p", ssk); | |
1868 | mptcp_set_timeout(sk, ssk); | |
1869 | tcp_send_ack(ssk); | |
1870 | } | |
21498490 PK |
1871 | break; |
1872 | } | |
1873 | ||
21498490 PK |
1874 | release_sock(ssk); |
1875 | } | |
1876 | ||
6920b851 MM |
1877 | static const unsigned char new_state[16] = { |
1878 | /* current state: new state: action: */ | |
1879 | [0 /* (Invalid) */] = TCP_CLOSE, | |
1880 | [TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
1881 | [TCP_SYN_SENT] = TCP_CLOSE, | |
1882 | [TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN, | |
1883 | [TCP_FIN_WAIT1] = TCP_FIN_WAIT1, | |
1884 | [TCP_FIN_WAIT2] = TCP_FIN_WAIT2, | |
1885 | [TCP_TIME_WAIT] = TCP_CLOSE, /* should not happen ! */ | |
1886 | [TCP_CLOSE] = TCP_CLOSE, | |
1887 | [TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN, | |
1888 | [TCP_LAST_ACK] = TCP_LAST_ACK, | |
1889 | [TCP_LISTEN] = TCP_CLOSE, | |
1890 | [TCP_CLOSING] = TCP_CLOSING, | |
1891 | [TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */ | |
1892 | }; | |
1893 | ||
1894 | static int mptcp_close_state(struct sock *sk) | |
1895 | { | |
1896 | int next = (int)new_state[sk->sk_state]; | |
1897 | int ns = next & TCP_STATE_MASK; | |
1898 | ||
1899 | inet_sk_state_store(sk, ns); | |
1900 | ||
1901 | return next & TCP_ACTION_FIN; | |
1902 | } | |
1903 | ||
2c22c06c | 1904 | static void mptcp_close(struct sock *sk, long timeout) |
f870fa0b | 1905 | { |
cec37a6e | 1906 | struct mptcp_subflow_context *subflow, *tmp; |
f870fa0b | 1907 | struct mptcp_sock *msk = mptcp_sk(sk); |
b2c5b614 | 1908 | LIST_HEAD(conn_list); |
f870fa0b | 1909 | |
2c22c06c | 1910 | lock_sock(sk); |
43b54c6e MM |
1911 | sk->sk_shutdown = SHUTDOWN_MASK; |
1912 | ||
1913 | if (sk->sk_state == TCP_LISTEN) { | |
1914 | inet_sk_state_store(sk, TCP_CLOSE); | |
1915 | goto cleanup; | |
1916 | } else if (sk->sk_state == TCP_CLOSE) { | |
1917 | goto cleanup; | |
1918 | } | |
1919 | ||
1920 | if (__mptcp_check_fallback(msk)) { | |
1921 | goto update_state; | |
1922 | } else if (mptcp_close_state(sk)) { | |
1923 | pr_debug("Sending DATA_FIN sk=%p", sk); | |
1924 | WRITE_ONCE(msk->write_seq, msk->write_seq + 1); | |
1925 | WRITE_ONCE(msk->snd_data_fin_enable, 1); | |
1926 | ||
1927 | mptcp_for_each_subflow(msk, subflow) { | |
1928 | struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow); | |
1929 | ||
1930 | mptcp_subflow_shutdown(sk, tcp_sk, SHUTDOWN_MASK); | |
1931 | } | |
1932 | } | |
2c22c06c | 1933 | |
43b54c6e MM |
1934 | sk_stream_wait_close(sk, timeout); |
1935 | ||
1936 | update_state: | |
f870fa0b MM |
1937 | inet_sk_state_store(sk, TCP_CLOSE); |
1938 | ||
43b54c6e | 1939 | cleanup: |
10f6d46c PA |
1940 | /* be sure to always acquire the join list lock, to sync vs |
1941 | * mptcp_finish_join(). | |
1942 | */ | |
1943 | spin_lock_bh(&msk->join_list_lock); | |
1944 | list_splice_tail_init(&msk->join_list, &msk->conn_list); | |
1945 | spin_unlock_bh(&msk->join_list_lock); | |
b2c5b614 FW |
1946 | list_splice_init(&msk->conn_list, &conn_list); |
1947 | ||
18b683bf PA |
1948 | __mptcp_clear_xmit(sk); |
1949 | ||
b2c5b614 FW |
1950 | release_sock(sk); |
1951 | ||
1952 | list_for_each_entry_safe(subflow, tmp, &conn_list, node) { | |
cec37a6e | 1953 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); |
cec37a6e | 1954 | __mptcp_close_ssk(sk, ssk, subflow, timeout); |
f870fa0b MM |
1955 | } |
1956 | ||
80992017 PA |
1957 | mptcp_cancel_work(sk); |
1958 | ||
6771bfd9 FW |
1959 | __skb_queue_purge(&sk->sk_receive_queue); |
1960 | ||
cec37a6e | 1961 | sk_common_release(sk); |
f870fa0b MM |
1962 | } |
1963 | ||
cf7da0d6 PK |
1964 | static void mptcp_copy_inaddrs(struct sock *msk, const struct sock *ssk) |
1965 | { | |
1966 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1967 | const struct ipv6_pinfo *ssk6 = inet6_sk(ssk); | |
1968 | struct ipv6_pinfo *msk6 = inet6_sk(msk); | |
1969 | ||
1970 | msk->sk_v6_daddr = ssk->sk_v6_daddr; | |
1971 | msk->sk_v6_rcv_saddr = ssk->sk_v6_rcv_saddr; | |
1972 | ||
1973 | if (msk6 && ssk6) { | |
1974 | msk6->saddr = ssk6->saddr; | |
1975 | msk6->flow_label = ssk6->flow_label; | |
1976 | } | |
1977 | #endif | |
1978 | ||
1979 | inet_sk(msk)->inet_num = inet_sk(ssk)->inet_num; | |
1980 | inet_sk(msk)->inet_dport = inet_sk(ssk)->inet_dport; | |
1981 | inet_sk(msk)->inet_sport = inet_sk(ssk)->inet_sport; | |
1982 | inet_sk(msk)->inet_daddr = inet_sk(ssk)->inet_daddr; | |
1983 | inet_sk(msk)->inet_saddr = inet_sk(ssk)->inet_saddr; | |
1984 | inet_sk(msk)->inet_rcv_saddr = inet_sk(ssk)->inet_rcv_saddr; | |
1985 | } | |
1986 | ||
18b683bf PA |
1987 | static int mptcp_disconnect(struct sock *sk, int flags) |
1988 | { | |
42c556fe FW |
1989 | /* Should never be called. |
1990 | * inet_stream_connect() calls ->disconnect, but that | |
1991 | * refers to the subflow socket, not the mptcp one. | |
1992 | */ | |
1993 | WARN_ON_ONCE(1); | |
1994 | return 0; | |
18b683bf PA |
1995 | } |
1996 | ||
b0519de8 FW |
1997 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
1998 | static struct ipv6_pinfo *mptcp_inet6_sk(const struct sock *sk) | |
1999 | { | |
2000 | unsigned int offset = sizeof(struct mptcp6_sock) - sizeof(struct ipv6_pinfo); | |
2001 | ||
2002 | return (struct ipv6_pinfo *)(((u8 *)sk) + offset); | |
2003 | } | |
2004 | #endif | |
2005 | ||
fca5c82c | 2006 | struct sock *mptcp_sk_clone(const struct sock *sk, |
cfde141e | 2007 | const struct mptcp_options_received *mp_opt, |
fca5c82c | 2008 | struct request_sock *req) |
b0519de8 | 2009 | { |
58b09919 | 2010 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); |
b0519de8 | 2011 | struct sock *nsk = sk_clone_lock(sk, GFP_ATOMIC); |
58b09919 PA |
2012 | struct mptcp_sock *msk; |
2013 | u64 ack_seq; | |
b0519de8 FW |
2014 | |
2015 | if (!nsk) | |
2016 | return NULL; | |
2017 | ||
2018 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
2019 | if (nsk->sk_family == AF_INET6) | |
2020 | inet_sk(nsk)->pinet6 = mptcp_inet6_sk(nsk); | |
2021 | #endif | |
2022 | ||
58b09919 PA |
2023 | __mptcp_init_sock(nsk); |
2024 | ||
2025 | msk = mptcp_sk(nsk); | |
2026 | msk->local_key = subflow_req->local_key; | |
2027 | msk->token = subflow_req->token; | |
2028 | msk->subflow = NULL; | |
b93df08c | 2029 | WRITE_ONCE(msk->fully_established, false); |
58b09919 | 2030 | |
58b09919 | 2031 | msk->write_seq = subflow_req->idsn + 1; |
cc9d2566 | 2032 | atomic64_set(&msk->snd_una, msk->write_seq); |
cfde141e | 2033 | if (mp_opt->mp_capable) { |
58b09919 | 2034 | msk->can_ack = true; |
cfde141e | 2035 | msk->remote_key = mp_opt->sndr_key; |
58b09919 PA |
2036 | mptcp_crypto_key_sha(msk->remote_key, NULL, &ack_seq); |
2037 | ack_seq++; | |
2038 | msk->ack_seq = ack_seq; | |
2039 | } | |
7f20d5fc | 2040 | |
5e20087d | 2041 | sock_reset_flag(nsk, SOCK_RCU_FREE); |
7f20d5fc PA |
2042 | /* will be fully established after successful MPC subflow creation */ |
2043 | inet_sk_state_store(nsk, TCP_SYN_RECV); | |
58b09919 PA |
2044 | bh_unlock_sock(nsk); |
2045 | ||
2046 | /* keep a single reference */ | |
2047 | __sock_put(nsk); | |
b0519de8 FW |
2048 | return nsk; |
2049 | } | |
2050 | ||
a6b118fe FW |
2051 | void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk) |
2052 | { | |
2053 | const struct tcp_sock *tp = tcp_sk(ssk); | |
2054 | ||
2055 | msk->rcvq_space.copied = 0; | |
2056 | msk->rcvq_space.rtt_us = 0; | |
2057 | ||
2058 | msk->rcvq_space.time = tp->tcp_mstamp; | |
2059 | ||
2060 | /* initial rcv_space offering made to peer */ | |
2061 | msk->rcvq_space.space = min_t(u32, tp->rcv_wnd, | |
2062 | TCP_INIT_CWND * tp->advmss); | |
2063 | if (msk->rcvq_space.space == 0) | |
2064 | msk->rcvq_space.space = TCP_INIT_CWND * TCP_MSS_DEFAULT; | |
2065 | } | |
2066 | ||
cf7da0d6 PK |
2067 | static struct sock *mptcp_accept(struct sock *sk, int flags, int *err, |
2068 | bool kern) | |
2069 | { | |
2070 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2071 | struct socket *listener; | |
2072 | struct sock *newsk; | |
2073 | ||
2074 | listener = __mptcp_nmpc_socket(msk); | |
2075 | if (WARN_ON_ONCE(!listener)) { | |
2076 | *err = -EINVAL; | |
2077 | return NULL; | |
2078 | } | |
2079 | ||
2080 | pr_debug("msk=%p, listener=%p", msk, mptcp_subflow_ctx(listener->sk)); | |
2081 | newsk = inet_csk_accept(listener->sk, flags, err, kern); | |
2082 | if (!newsk) | |
2083 | return NULL; | |
2084 | ||
2085 | pr_debug("msk=%p, subflow is mptcp=%d", msk, sk_is_mptcp(newsk)); | |
cf7da0d6 PK |
2086 | if (sk_is_mptcp(newsk)) { |
2087 | struct mptcp_subflow_context *subflow; | |
2088 | struct sock *new_mptcp_sock; | |
2089 | struct sock *ssk = newsk; | |
2090 | ||
2091 | subflow = mptcp_subflow_ctx(newsk); | |
58b09919 | 2092 | new_mptcp_sock = subflow->conn; |
cf7da0d6 | 2093 | |
58b09919 PA |
2094 | /* is_mptcp should be false if subflow->conn is missing, see |
2095 | * subflow_syn_recv_sock() | |
2096 | */ | |
2097 | if (WARN_ON_ONCE(!new_mptcp_sock)) { | |
2098 | tcp_sk(newsk)->is_mptcp = 0; | |
2099 | return newsk; | |
cf7da0d6 PK |
2100 | } |
2101 | ||
58b09919 PA |
2102 | /* acquire the 2nd reference for the owning socket */ |
2103 | sock_hold(new_mptcp_sock); | |
cf7da0d6 | 2104 | |
58b09919 PA |
2105 | local_bh_disable(); |
2106 | bh_lock_sock(new_mptcp_sock); | |
cf7da0d6 | 2107 | msk = mptcp_sk(new_mptcp_sock); |
8ab183de | 2108 | msk->first = newsk; |
cf7da0d6 PK |
2109 | |
2110 | newsk = new_mptcp_sock; | |
2111 | mptcp_copy_inaddrs(newsk, ssk); | |
2112 | list_add(&subflow->node, &msk->conn_list); | |
2113 | ||
a6b118fe | 2114 | mptcp_rcv_space_init(msk, ssk); |
cf7da0d6 | 2115 | bh_unlock_sock(new_mptcp_sock); |
fc518953 FW |
2116 | |
2117 | __MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVEACK); | |
cf7da0d6 | 2118 | local_bh_enable(); |
fc518953 FW |
2119 | } else { |
2120 | MPTCP_INC_STATS(sock_net(sk), | |
2121 | MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); | |
cf7da0d6 PK |
2122 | } |
2123 | ||
2124 | return newsk; | |
2125 | } | |
2126 | ||
79c0949e PK |
2127 | static void mptcp_destroy(struct sock *sk) |
2128 | { | |
c9fd9c5f FW |
2129 | struct mptcp_sock *msk = mptcp_sk(sk); |
2130 | ||
ab174ad8 | 2131 | skb_rbtree_purge(&msk->out_of_order_queue); |
2c5ebd00 | 2132 | mptcp_token_destroy(msk); |
c9fd9c5f FW |
2133 | if (msk->cached_ext) |
2134 | __skb_ext_put(msk->cached_ext); | |
d027236c PA |
2135 | |
2136 | sk_sockets_allocated_dec(sk); | |
79c0949e PK |
2137 | } |
2138 | ||
fd1452d8 | 2139 | static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname, |
a7b75c5a | 2140 | sockptr_t optval, unsigned int optlen) |
fd1452d8 FW |
2141 | { |
2142 | struct sock *sk = (struct sock *)msk; | |
2143 | struct socket *ssock; | |
2144 | int ret; | |
2145 | ||
2146 | switch (optname) { | |
2147 | case SO_REUSEPORT: | |
2148 | case SO_REUSEADDR: | |
2149 | lock_sock(sk); | |
2150 | ssock = __mptcp_nmpc_socket(msk); | |
2151 | if (!ssock) { | |
2152 | release_sock(sk); | |
2153 | return -EINVAL; | |
2154 | } | |
2155 | ||
a7b75c5a | 2156 | ret = sock_setsockopt(ssock, SOL_SOCKET, optname, optval, optlen); |
fd1452d8 FW |
2157 | if (ret == 0) { |
2158 | if (optname == SO_REUSEPORT) | |
2159 | sk->sk_reuseport = ssock->sk->sk_reuseport; | |
2160 | else if (optname == SO_REUSEADDR) | |
2161 | sk->sk_reuse = ssock->sk->sk_reuse; | |
2162 | } | |
2163 | release_sock(sk); | |
2164 | return ret; | |
2165 | } | |
2166 | ||
a7b75c5a | 2167 | return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen); |
fd1452d8 FW |
2168 | } |
2169 | ||
c9b95a13 | 2170 | static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, |
a7b75c5a | 2171 | sockptr_t optval, unsigned int optlen) |
c9b95a13 FW |
2172 | { |
2173 | struct sock *sk = (struct sock *)msk; | |
2174 | int ret = -EOPNOTSUPP; | |
2175 | struct socket *ssock; | |
2176 | ||
2177 | switch (optname) { | |
2178 | case IPV6_V6ONLY: | |
2179 | lock_sock(sk); | |
2180 | ssock = __mptcp_nmpc_socket(msk); | |
2181 | if (!ssock) { | |
2182 | release_sock(sk); | |
2183 | return -EINVAL; | |
2184 | } | |
2185 | ||
2186 | ret = tcp_setsockopt(ssock->sk, SOL_IPV6, optname, optval, optlen); | |
2187 | if (ret == 0) | |
2188 | sk->sk_ipv6only = ssock->sk->sk_ipv6only; | |
2189 | ||
2190 | release_sock(sk); | |
2191 | break; | |
2192 | } | |
2193 | ||
2194 | return ret; | |
2195 | } | |
2196 | ||
717e79c8 | 2197 | static int mptcp_setsockopt(struct sock *sk, int level, int optname, |
a7b75c5a | 2198 | sockptr_t optval, unsigned int optlen) |
717e79c8 PK |
2199 | { |
2200 | struct mptcp_sock *msk = mptcp_sk(sk); | |
76660afb | 2201 | struct sock *ssk; |
717e79c8 PK |
2202 | |
2203 | pr_debug("msk=%p", msk); | |
2204 | ||
83f0c10b | 2205 | if (level == SOL_SOCKET) |
fd1452d8 | 2206 | return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); |
83f0c10b | 2207 | |
717e79c8 | 2208 | /* @@ the meaning of setsockopt() when the socket is connected and |
b6e4a1ae MM |
2209 | * there are multiple subflows is not yet defined. It is up to the |
2210 | * MPTCP-level socket to configure the subflows until the subflow | |
2211 | * is in TCP fallback, when TCP socket options are passed through | |
2212 | * to the one remaining subflow. | |
717e79c8 PK |
2213 | */ |
2214 | lock_sock(sk); | |
76660afb | 2215 | ssk = __mptcp_tcp_fallback(msk); |
e154659b | 2216 | release_sock(sk); |
76660afb PA |
2217 | if (ssk) |
2218 | return tcp_setsockopt(ssk, level, optname, optval, optlen); | |
50e741bb | 2219 | |
c9b95a13 FW |
2220 | if (level == SOL_IPV6) |
2221 | return mptcp_setsockopt_v6(msk, optname, optval, optlen); | |
2222 | ||
b6e4a1ae | 2223 | return -EOPNOTSUPP; |
717e79c8 PK |
2224 | } |
2225 | ||
2226 | static int mptcp_getsockopt(struct sock *sk, int level, int optname, | |
50e741bb | 2227 | char __user *optval, int __user *option) |
717e79c8 PK |
2228 | { |
2229 | struct mptcp_sock *msk = mptcp_sk(sk); | |
76660afb | 2230 | struct sock *ssk; |
717e79c8 PK |
2231 | |
2232 | pr_debug("msk=%p", msk); | |
2233 | ||
b6e4a1ae MM |
2234 | /* @@ the meaning of setsockopt() when the socket is connected and |
2235 | * there are multiple subflows is not yet defined. It is up to the | |
2236 | * MPTCP-level socket to configure the subflows until the subflow | |
2237 | * is in TCP fallback, when socket options are passed through | |
2238 | * to the one remaining subflow. | |
717e79c8 PK |
2239 | */ |
2240 | lock_sock(sk); | |
76660afb | 2241 | ssk = __mptcp_tcp_fallback(msk); |
e154659b | 2242 | release_sock(sk); |
76660afb PA |
2243 | if (ssk) |
2244 | return tcp_getsockopt(ssk, level, optname, optval, option); | |
50e741bb | 2245 | |
b6e4a1ae | 2246 | return -EOPNOTSUPP; |
717e79c8 PK |
2247 | } |
2248 | ||
b51f9b80 PA |
2249 | #define MPTCP_DEFERRED_ALL (TCPF_DELACK_TIMER_DEFERRED | \ |
2250 | TCPF_WRITE_TIMER_DEFERRED) | |
14c441b5 PA |
2251 | |
2252 | /* this is very alike tcp_release_cb() but we must handle differently a | |
2253 | * different set of events | |
2254 | */ | |
2255 | static void mptcp_release_cb(struct sock *sk) | |
2256 | { | |
2257 | unsigned long flags, nflags; | |
2258 | ||
2259 | do { | |
2260 | flags = sk->sk_tsq_flags; | |
2261 | if (!(flags & MPTCP_DEFERRED_ALL)) | |
2262 | return; | |
2263 | nflags = flags & ~MPTCP_DEFERRED_ALL; | |
2264 | } while (cmpxchg(&sk->sk_tsq_flags, flags, nflags) != flags); | |
2265 | ||
b51f9b80 PA |
2266 | sock_release_ownership(sk); |
2267 | ||
14c441b5 PA |
2268 | if (flags & TCPF_DELACK_TIMER_DEFERRED) { |
2269 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2270 | struct sock *ssk; | |
2271 | ||
2272 | ssk = mptcp_subflow_recv_lookup(msk); | |
2273 | if (!ssk || !schedule_work(&msk->work)) | |
2274 | __sock_put(sk); | |
2275 | } | |
b51f9b80 PA |
2276 | |
2277 | if (flags & TCPF_WRITE_TIMER_DEFERRED) { | |
2278 | mptcp_retransmit_handler(sk); | |
2279 | __sock_put(sk); | |
2280 | } | |
14c441b5 PA |
2281 | } |
2282 | ||
2c5ebd00 PA |
2283 | static int mptcp_hash(struct sock *sk) |
2284 | { | |
2285 | /* should never be called, | |
2286 | * we hash the TCP subflows not the master socket | |
2287 | */ | |
2288 | WARN_ON_ONCE(1); | |
2289 | return 0; | |
2290 | } | |
2291 | ||
2292 | static void mptcp_unhash(struct sock *sk) | |
2293 | { | |
2294 | /* called from sk_common_release(), but nothing to do here */ | |
2295 | } | |
2296 | ||
cec37a6e | 2297 | static int mptcp_get_port(struct sock *sk, unsigned short snum) |
f870fa0b MM |
2298 | { |
2299 | struct mptcp_sock *msk = mptcp_sk(sk); | |
cec37a6e | 2300 | struct socket *ssock; |
f870fa0b | 2301 | |
cec37a6e PK |
2302 | ssock = __mptcp_nmpc_socket(msk); |
2303 | pr_debug("msk=%p, subflow=%p", msk, ssock); | |
2304 | if (WARN_ON_ONCE(!ssock)) | |
2305 | return -EINVAL; | |
f870fa0b | 2306 | |
cec37a6e PK |
2307 | return inet_csk_get_port(ssock->sk, snum); |
2308 | } | |
f870fa0b | 2309 | |
cec37a6e PK |
2310 | void mptcp_finish_connect(struct sock *ssk) |
2311 | { | |
2312 | struct mptcp_subflow_context *subflow; | |
2313 | struct mptcp_sock *msk; | |
2314 | struct sock *sk; | |
6d0060f6 | 2315 | u64 ack_seq; |
f870fa0b | 2316 | |
cec37a6e | 2317 | subflow = mptcp_subflow_ctx(ssk); |
cec37a6e PK |
2318 | sk = subflow->conn; |
2319 | msk = mptcp_sk(sk); | |
2320 | ||
648ef4b8 MM |
2321 | pr_debug("msk=%p, token=%u", sk, subflow->token); |
2322 | ||
6d0060f6 MM |
2323 | mptcp_crypto_key_sha(subflow->remote_key, NULL, &ack_seq); |
2324 | ack_seq++; | |
648ef4b8 MM |
2325 | subflow->map_seq = ack_seq; |
2326 | subflow->map_subflow_seq = 1; | |
6d0060f6 | 2327 | |
cec37a6e PK |
2328 | /* the socket is not connected yet, no msk/subflow ops can access/race |
2329 | * accessing the field below | |
2330 | */ | |
2331 | WRITE_ONCE(msk->remote_key, subflow->remote_key); | |
2332 | WRITE_ONCE(msk->local_key, subflow->local_key); | |
6d0060f6 MM |
2333 | WRITE_ONCE(msk->write_seq, subflow->idsn + 1); |
2334 | WRITE_ONCE(msk->ack_seq, ack_seq); | |
d22f4988 | 2335 | WRITE_ONCE(msk->can_ack, 1); |
cc9d2566 | 2336 | atomic64_set(&msk->snd_una, msk->write_seq); |
1b1c7a0e PK |
2337 | |
2338 | mptcp_pm_new_connection(msk, 0); | |
a6b118fe FW |
2339 | |
2340 | mptcp_rcv_space_init(msk, ssk); | |
f870fa0b MM |
2341 | } |
2342 | ||
cf7da0d6 PK |
2343 | static void mptcp_sock_graft(struct sock *sk, struct socket *parent) |
2344 | { | |
2345 | write_lock_bh(&sk->sk_callback_lock); | |
2346 | rcu_assign_pointer(sk->sk_wq, &parent->wq); | |
2347 | sk_set_socket(sk, parent); | |
2348 | sk->sk_uid = SOCK_INODE(parent)->i_uid; | |
2349 | write_unlock_bh(&sk->sk_callback_lock); | |
2350 | } | |
2351 | ||
f296234c PK |
2352 | bool mptcp_finish_join(struct sock *sk) |
2353 | { | |
2354 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
2355 | struct mptcp_sock *msk = mptcp_sk(subflow->conn); | |
2356 | struct sock *parent = (void *)msk; | |
2357 | struct socket *parent_sock; | |
ec3edaa7 | 2358 | bool ret; |
f296234c PK |
2359 | |
2360 | pr_debug("msk=%p, subflow=%p", msk, subflow); | |
2361 | ||
2362 | /* mptcp socket already closing? */ | |
b93df08c | 2363 | if (!mptcp_is_fully_established(parent)) |
f296234c PK |
2364 | return false; |
2365 | ||
2366 | if (!msk->pm.server_side) | |
2367 | return true; | |
2368 | ||
10f6d46c PA |
2369 | if (!mptcp_pm_allow_new_subflow(msk)) |
2370 | return false; | |
2371 | ||
2372 | /* active connections are already on conn_list, and we can't acquire | |
2373 | * msk lock here. | |
2374 | * use the join list lock as synchronization point and double-check | |
2375 | * msk status to avoid racing with mptcp_close() | |
2376 | */ | |
2377 | spin_lock_bh(&msk->join_list_lock); | |
2378 | ret = inet_sk_state_load(parent) == TCP_ESTABLISHED; | |
2379 | if (ret && !WARN_ON_ONCE(!list_empty(&subflow->node))) | |
2380 | list_add_tail(&subflow->node, &msk->join_list); | |
2381 | spin_unlock_bh(&msk->join_list_lock); | |
2382 | if (!ret) | |
2383 | return false; | |
2384 | ||
2385 | /* attach to msk socket only after we are sure he will deal with us | |
2386 | * at close time | |
2387 | */ | |
f296234c PK |
2388 | parent_sock = READ_ONCE(parent->sk_socket); |
2389 | if (parent_sock && !sk->sk_socket) | |
2390 | mptcp_sock_graft(sk, parent_sock); | |
10f6d46c PA |
2391 | subflow->map_seq = msk->ack_seq; |
2392 | return true; | |
f296234c PK |
2393 | } |
2394 | ||
1891c4a0 FW |
2395 | static bool mptcp_memory_free(const struct sock *sk, int wake) |
2396 | { | |
2397 | struct mptcp_sock *msk = mptcp_sk(sk); | |
2398 | ||
2399 | return wake ? test_bit(MPTCP_SEND_SPACE, &msk->flags) : true; | |
2400 | } | |
2401 | ||
f870fa0b MM |
2402 | static struct proto mptcp_prot = { |
2403 | .name = "MPTCP", | |
2404 | .owner = THIS_MODULE, | |
2405 | .init = mptcp_init_sock, | |
18b683bf | 2406 | .disconnect = mptcp_disconnect, |
f870fa0b | 2407 | .close = mptcp_close, |
cf7da0d6 | 2408 | .accept = mptcp_accept, |
717e79c8 PK |
2409 | .setsockopt = mptcp_setsockopt, |
2410 | .getsockopt = mptcp_getsockopt, | |
f870fa0b | 2411 | .shutdown = tcp_shutdown, |
79c0949e | 2412 | .destroy = mptcp_destroy, |
f870fa0b MM |
2413 | .sendmsg = mptcp_sendmsg, |
2414 | .recvmsg = mptcp_recvmsg, | |
14c441b5 | 2415 | .release_cb = mptcp_release_cb, |
2c5ebd00 PA |
2416 | .hash = mptcp_hash, |
2417 | .unhash = mptcp_unhash, | |
cec37a6e | 2418 | .get_port = mptcp_get_port, |
d027236c PA |
2419 | .sockets_allocated = &mptcp_sockets_allocated, |
2420 | .memory_allocated = &tcp_memory_allocated, | |
2421 | .memory_pressure = &tcp_memory_pressure, | |
1891c4a0 | 2422 | .stream_memory_free = mptcp_memory_free, |
d027236c PA |
2423 | .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem), |
2424 | .sysctl_mem = sysctl_tcp_mem, | |
f870fa0b | 2425 | .obj_size = sizeof(struct mptcp_sock), |
2c5ebd00 | 2426 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
f870fa0b MM |
2427 | .no_autobind = true, |
2428 | }; | |
2429 | ||
2303f994 PK |
2430 | static int mptcp_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) |
2431 | { | |
2432 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
2433 | struct socket *ssock; | |
cf7da0d6 | 2434 | int err; |
2303f994 PK |
2435 | |
2436 | lock_sock(sock->sk); | |
fa68018d PA |
2437 | ssock = __mptcp_nmpc_socket(msk); |
2438 | if (!ssock) { | |
2439 | err = -EINVAL; | |
2303f994 PK |
2440 | goto unlock; |
2441 | } | |
2442 | ||
2443 | err = ssock->ops->bind(ssock, uaddr, addr_len); | |
cf7da0d6 PK |
2444 | if (!err) |
2445 | mptcp_copy_inaddrs(sock->sk, ssock->sk); | |
2303f994 PK |
2446 | |
2447 | unlock: | |
2448 | release_sock(sock->sk); | |
2449 | return err; | |
2450 | } | |
2451 | ||
0235d075 PA |
2452 | static void mptcp_subflow_early_fallback(struct mptcp_sock *msk, |
2453 | struct mptcp_subflow_context *subflow) | |
2454 | { | |
2455 | subflow->request_mptcp = 0; | |
2456 | __mptcp_do_fallback(msk); | |
2457 | } | |
2458 | ||
2303f994 PK |
2459 | static int mptcp_stream_connect(struct socket *sock, struct sockaddr *uaddr, |
2460 | int addr_len, int flags) | |
2461 | { | |
2462 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
2c5ebd00 | 2463 | struct mptcp_subflow_context *subflow; |
2303f994 PK |
2464 | struct socket *ssock; |
2465 | int err; | |
2466 | ||
2467 | lock_sock(sock->sk); | |
41be81a8 PA |
2468 | if (sock->state != SS_UNCONNECTED && msk->subflow) { |
2469 | /* pending connection or invalid state, let existing subflow | |
2470 | * cope with that | |
2471 | */ | |
2472 | ssock = msk->subflow; | |
2473 | goto do_connect; | |
2474 | } | |
2475 | ||
fa68018d PA |
2476 | ssock = __mptcp_nmpc_socket(msk); |
2477 | if (!ssock) { | |
2478 | err = -EINVAL; | |
2303f994 PK |
2479 | goto unlock; |
2480 | } | |
2481 | ||
fa68018d PA |
2482 | mptcp_token_destroy(msk); |
2483 | inet_sk_state_store(sock->sk, TCP_SYN_SENT); | |
2c5ebd00 | 2484 | subflow = mptcp_subflow_ctx(ssock->sk); |
cf7da0d6 PK |
2485 | #ifdef CONFIG_TCP_MD5SIG |
2486 | /* no MPTCP if MD5SIG is enabled on this socket or we may run out of | |
2487 | * TCP option space. | |
2488 | */ | |
2489 | if (rcu_access_pointer(tcp_sk(ssock->sk)->md5sig_info)) | |
0235d075 | 2490 | mptcp_subflow_early_fallback(msk, subflow); |
cf7da0d6 | 2491 | #endif |
2c5ebd00 | 2492 | if (subflow->request_mptcp && mptcp_token_new_connect(ssock->sk)) |
0235d075 | 2493 | mptcp_subflow_early_fallback(msk, subflow); |
cf7da0d6 | 2494 | |
41be81a8 | 2495 | do_connect: |
2303f994 | 2496 | err = ssock->ops->connect(ssock, uaddr, addr_len, flags); |
41be81a8 PA |
2497 | sock->state = ssock->state; |
2498 | ||
2499 | /* on successful connect, the msk state will be moved to established by | |
2500 | * subflow_finish_connect() | |
2501 | */ | |
367fe04e | 2502 | if (!err || err == -EINPROGRESS) |
41be81a8 PA |
2503 | mptcp_copy_inaddrs(sock->sk, ssock->sk); |
2504 | else | |
2505 | inet_sk_state_store(sock->sk, inet_sk_state_load(ssock->sk)); | |
2303f994 PK |
2506 | |
2507 | unlock: | |
2508 | release_sock(sock->sk); | |
2509 | return err; | |
2510 | } | |
2511 | ||
cf7da0d6 PK |
2512 | static int mptcp_listen(struct socket *sock, int backlog) |
2513 | { | |
2514 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
2515 | struct socket *ssock; | |
2516 | int err; | |
2517 | ||
2518 | pr_debug("msk=%p", msk); | |
2519 | ||
2520 | lock_sock(sock->sk); | |
fa68018d PA |
2521 | ssock = __mptcp_nmpc_socket(msk); |
2522 | if (!ssock) { | |
2523 | err = -EINVAL; | |
cf7da0d6 PK |
2524 | goto unlock; |
2525 | } | |
2526 | ||
fa68018d PA |
2527 | mptcp_token_destroy(msk); |
2528 | inet_sk_state_store(sock->sk, TCP_LISTEN); | |
5e20087d FW |
2529 | sock_set_flag(sock->sk, SOCK_RCU_FREE); |
2530 | ||
cf7da0d6 PK |
2531 | err = ssock->ops->listen(ssock, backlog); |
2532 | inet_sk_state_store(sock->sk, inet_sk_state_load(ssock->sk)); | |
2533 | if (!err) | |
2534 | mptcp_copy_inaddrs(sock->sk, ssock->sk); | |
2535 | ||
2536 | unlock: | |
2537 | release_sock(sock->sk); | |
2538 | return err; | |
2539 | } | |
2540 | ||
cf7da0d6 PK |
2541 | static int mptcp_stream_accept(struct socket *sock, struct socket *newsock, |
2542 | int flags, bool kern) | |
2543 | { | |
2544 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
2545 | struct socket *ssock; | |
2546 | int err; | |
2547 | ||
2548 | pr_debug("msk=%p", msk); | |
2549 | ||
2550 | lock_sock(sock->sk); | |
2551 | if (sock->sk->sk_state != TCP_LISTEN) | |
2552 | goto unlock_fail; | |
2553 | ||
2554 | ssock = __mptcp_nmpc_socket(msk); | |
2555 | if (!ssock) | |
2556 | goto unlock_fail; | |
2557 | ||
8a05661b | 2558 | clear_bit(MPTCP_DATA_READY, &msk->flags); |
cf7da0d6 PK |
2559 | sock_hold(ssock->sk); |
2560 | release_sock(sock->sk); | |
2561 | ||
2562 | err = ssock->ops->accept(sock, newsock, flags, kern); | |
d2f77c53 | 2563 | if (err == 0 && !mptcp_is_tcpsk(newsock->sk)) { |
cf7da0d6 PK |
2564 | struct mptcp_sock *msk = mptcp_sk(newsock->sk); |
2565 | struct mptcp_subflow_context *subflow; | |
2566 | ||
2567 | /* set ssk->sk_socket of accept()ed flows to mptcp socket. | |
2568 | * This is needed so NOSPACE flag can be set from tcp stack. | |
2569 | */ | |
ec3edaa7 | 2570 | __mptcp_flush_join_list(msk); |
190f8b06 | 2571 | mptcp_for_each_subflow(msk, subflow) { |
cf7da0d6 PK |
2572 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); |
2573 | ||
2574 | if (!ssk->sk_socket) | |
2575 | mptcp_sock_graft(ssk, newsock); | |
2576 | } | |
cf7da0d6 PK |
2577 | } |
2578 | ||
8a05661b PA |
2579 | if (inet_csk_listen_poll(ssock->sk)) |
2580 | set_bit(MPTCP_DATA_READY, &msk->flags); | |
cf7da0d6 PK |
2581 | sock_put(ssock->sk); |
2582 | return err; | |
2583 | ||
2584 | unlock_fail: | |
2585 | release_sock(sock->sk); | |
2586 | return -EINVAL; | |
2587 | } | |
2588 | ||
8a05661b PA |
2589 | static __poll_t mptcp_check_readable(struct mptcp_sock *msk) |
2590 | { | |
2591 | return test_bit(MPTCP_DATA_READY, &msk->flags) ? EPOLLIN | EPOLLRDNORM : | |
2592 | 0; | |
2593 | } | |
2594 | ||
2303f994 PK |
2595 | static __poll_t mptcp_poll(struct file *file, struct socket *sock, |
2596 | struct poll_table_struct *wait) | |
2597 | { | |
1891c4a0 | 2598 | struct sock *sk = sock->sk; |
8ab183de | 2599 | struct mptcp_sock *msk; |
2303f994 | 2600 | __poll_t mask = 0; |
8a05661b | 2601 | int state; |
2303f994 | 2602 | |
1891c4a0 | 2603 | msk = mptcp_sk(sk); |
1891c4a0 | 2604 | sock_poll_wait(file, sock, wait); |
1891c4a0 | 2605 | |
8a05661b | 2606 | state = inet_sk_state_load(sk); |
6719331c | 2607 | pr_debug("msk=%p state=%d flags=%lx", msk, state, msk->flags); |
8a05661b PA |
2608 | if (state == TCP_LISTEN) |
2609 | return mptcp_check_readable(msk); | |
2610 | ||
2611 | if (state != TCP_SYN_SENT && state != TCP_SYN_RECV) { | |
2612 | mask |= mptcp_check_readable(msk); | |
63561a40 | 2613 | if (test_bit(MPTCP_SEND_SPACE, &msk->flags)) |
8a05661b PA |
2614 | mask |= EPOLLOUT | EPOLLWRNORM; |
2615 | } | |
1891c4a0 FW |
2616 | if (sk->sk_shutdown & RCV_SHUTDOWN) |
2617 | mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP; | |
2618 | ||
2303f994 PK |
2619 | return mask; |
2620 | } | |
2621 | ||
21498490 PK |
2622 | static int mptcp_shutdown(struct socket *sock, int how) |
2623 | { | |
2624 | struct mptcp_sock *msk = mptcp_sk(sock->sk); | |
2625 | struct mptcp_subflow_context *subflow; | |
2626 | int ret = 0; | |
2627 | ||
2628 | pr_debug("sk=%p, how=%d", msk, how); | |
2629 | ||
2630 | lock_sock(sock->sk); | |
21498490 PK |
2631 | |
2632 | how++; | |
21498490 PK |
2633 | if ((how & ~SHUTDOWN_MASK) || !how) { |
2634 | ret = -EINVAL; | |
2635 | goto out_unlock; | |
2636 | } | |
2637 | ||
2638 | if (sock->state == SS_CONNECTING) { | |
2639 | if ((1 << sock->sk->sk_state) & | |
2640 | (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE)) | |
2641 | sock->state = SS_DISCONNECTING; | |
2642 | else | |
2643 | sock->state = SS_CONNECTED; | |
2644 | } | |
2645 | ||
43b54c6e MM |
2646 | /* If we've already sent a FIN, or it's a closed state, skip this. */ |
2647 | if (__mptcp_check_fallback(msk)) { | |
2648 | if (how == SHUT_WR || how == SHUT_RDWR) | |
2649 | inet_sk_state_store(sock->sk, TCP_FIN_WAIT1); | |
7279da61 | 2650 | |
43b54c6e MM |
2651 | mptcp_for_each_subflow(msk, subflow) { |
2652 | struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow); | |
21498490 | 2653 | |
43b54c6e MM |
2654 | mptcp_subflow_shutdown(sock->sk, tcp_sk, how); |
2655 | } | |
2656 | } else if ((how & SEND_SHUTDOWN) && | |
2657 | ((1 << sock->sk->sk_state) & | |
2658 | (TCPF_ESTABLISHED | TCPF_SYN_SENT | | |
2659 | TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) && | |
2660 | mptcp_close_state(sock->sk)) { | |
2661 | __mptcp_flush_join_list(msk); | |
2662 | ||
2663 | WRITE_ONCE(msk->write_seq, msk->write_seq + 1); | |
2664 | WRITE_ONCE(msk->snd_data_fin_enable, 1); | |
2665 | ||
2666 | mptcp_for_each_subflow(msk, subflow) { | |
2667 | struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow); | |
2668 | ||
2669 | mptcp_subflow_shutdown(sock->sk, tcp_sk, how); | |
2670 | } | |
21498490 PK |
2671 | } |
2672 | ||
e1ff9e82 DC |
2673 | /* Wake up anyone sleeping in poll. */ |
2674 | sock->sk->sk_state_change(sock->sk); | |
2675 | ||
21498490 PK |
2676 | out_unlock: |
2677 | release_sock(sock->sk); | |
2678 | ||
2679 | return ret; | |
2680 | } | |
2681 | ||
e42f1ac6 FW |
2682 | static const struct proto_ops mptcp_stream_ops = { |
2683 | .family = PF_INET, | |
2684 | .owner = THIS_MODULE, | |
2685 | .release = inet_release, | |
2686 | .bind = mptcp_bind, | |
2687 | .connect = mptcp_stream_connect, | |
2688 | .socketpair = sock_no_socketpair, | |
2689 | .accept = mptcp_stream_accept, | |
d2f77c53 | 2690 | .getname = inet_getname, |
e42f1ac6 FW |
2691 | .poll = mptcp_poll, |
2692 | .ioctl = inet_ioctl, | |
2693 | .gettstamp = sock_gettstamp, | |
2694 | .listen = mptcp_listen, | |
2695 | .shutdown = mptcp_shutdown, | |
2696 | .setsockopt = sock_common_setsockopt, | |
2697 | .getsockopt = sock_common_getsockopt, | |
2698 | .sendmsg = inet_sendmsg, | |
2699 | .recvmsg = inet_recvmsg, | |
2700 | .mmap = sock_no_mmap, | |
2701 | .sendpage = inet_sendpage, | |
e42f1ac6 | 2702 | }; |
2303f994 | 2703 | |
f870fa0b MM |
2704 | static struct inet_protosw mptcp_protosw = { |
2705 | .type = SOCK_STREAM, | |
2706 | .protocol = IPPROTO_MPTCP, | |
2707 | .prot = &mptcp_prot, | |
2303f994 PK |
2708 | .ops = &mptcp_stream_ops, |
2709 | .flags = INET_PROTOSW_ICSK, | |
f870fa0b MM |
2710 | }; |
2711 | ||
d39dceca | 2712 | void __init mptcp_proto_init(void) |
f870fa0b | 2713 | { |
2303f994 | 2714 | mptcp_prot.h.hashinfo = tcp_prot.h.hashinfo; |
2303f994 | 2715 | |
d027236c PA |
2716 | if (percpu_counter_init(&mptcp_sockets_allocated, 0, GFP_KERNEL)) |
2717 | panic("Failed to allocate MPTCP pcpu counter\n"); | |
2718 | ||
2303f994 | 2719 | mptcp_subflow_init(); |
1b1c7a0e | 2720 | mptcp_pm_init(); |
2c5ebd00 | 2721 | mptcp_token_init(); |
2303f994 | 2722 | |
f870fa0b MM |
2723 | if (proto_register(&mptcp_prot, 1) != 0) |
2724 | panic("Failed to register MPTCP proto.\n"); | |
2725 | ||
2726 | inet_register_protosw(&mptcp_protosw); | |
6771bfd9 FW |
2727 | |
2728 | BUILD_BUG_ON(sizeof(struct mptcp_skb_cb) > sizeof_field(struct sk_buff, cb)); | |
f870fa0b MM |
2729 | } |
2730 | ||
2731 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
e42f1ac6 FW |
2732 | static const struct proto_ops mptcp_v6_stream_ops = { |
2733 | .family = PF_INET6, | |
2734 | .owner = THIS_MODULE, | |
2735 | .release = inet6_release, | |
2736 | .bind = mptcp_bind, | |
2737 | .connect = mptcp_stream_connect, | |
2738 | .socketpair = sock_no_socketpair, | |
2739 | .accept = mptcp_stream_accept, | |
d2f77c53 | 2740 | .getname = inet6_getname, |
e42f1ac6 FW |
2741 | .poll = mptcp_poll, |
2742 | .ioctl = inet6_ioctl, | |
2743 | .gettstamp = sock_gettstamp, | |
2744 | .listen = mptcp_listen, | |
2745 | .shutdown = mptcp_shutdown, | |
2746 | .setsockopt = sock_common_setsockopt, | |
2747 | .getsockopt = sock_common_getsockopt, | |
2748 | .sendmsg = inet6_sendmsg, | |
2749 | .recvmsg = inet6_recvmsg, | |
2750 | .mmap = sock_no_mmap, | |
2751 | .sendpage = inet_sendpage, | |
2752 | #ifdef CONFIG_COMPAT | |
3986912f | 2753 | .compat_ioctl = inet6_compat_ioctl, |
e42f1ac6 FW |
2754 | #endif |
2755 | }; | |
2756 | ||
f870fa0b MM |
2757 | static struct proto mptcp_v6_prot; |
2758 | ||
79c0949e PK |
2759 | static void mptcp_v6_destroy(struct sock *sk) |
2760 | { | |
2761 | mptcp_destroy(sk); | |
2762 | inet6_destroy_sock(sk); | |
2763 | } | |
2764 | ||
f870fa0b MM |
2765 | static struct inet_protosw mptcp_v6_protosw = { |
2766 | .type = SOCK_STREAM, | |
2767 | .protocol = IPPROTO_MPTCP, | |
2768 | .prot = &mptcp_v6_prot, | |
2303f994 | 2769 | .ops = &mptcp_v6_stream_ops, |
f870fa0b MM |
2770 | .flags = INET_PROTOSW_ICSK, |
2771 | }; | |
2772 | ||
d39dceca | 2773 | int __init mptcp_proto_v6_init(void) |
f870fa0b MM |
2774 | { |
2775 | int err; | |
2776 | ||
2777 | mptcp_v6_prot = mptcp_prot; | |
2778 | strcpy(mptcp_v6_prot.name, "MPTCPv6"); | |
2779 | mptcp_v6_prot.slab = NULL; | |
79c0949e | 2780 | mptcp_v6_prot.destroy = mptcp_v6_destroy; |
b0519de8 | 2781 | mptcp_v6_prot.obj_size = sizeof(struct mptcp6_sock); |
f870fa0b MM |
2782 | |
2783 | err = proto_register(&mptcp_v6_prot, 1); | |
2784 | if (err) | |
2785 | return err; | |
2786 | ||
2787 | err = inet6_register_protosw(&mptcp_v6_protosw); | |
2788 | if (err) | |
2789 | proto_unregister(&mptcp_v6_prot); | |
2790 | ||
2791 | return err; | |
2792 | } | |
2793 | #endif |