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