Commit | Line | Data |
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2303f994 PK |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Multipath TCP | |
3 | * | |
4 | * Copyright (c) 2017 - 2019, Intel Corporation. | |
5 | */ | |
6 | ||
79c0949e PK |
7 | #define pr_fmt(fmt) "MPTCP: " fmt |
8 | ||
2303f994 PK |
9 | #include <linux/kernel.h> |
10 | #include <linux/module.h> | |
11 | #include <linux/netdevice.h> | |
f296234c | 12 | #include <crypto/algapi.h> |
a24d22b2 | 13 | #include <crypto/sha2.h> |
2303f994 PK |
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> | |
cec37a6e PK |
19 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
20 | #include <net/ip6_route.h> | |
b19bc294 | 21 | #include <net/transp_v6.h> |
cec37a6e | 22 | #endif |
2303f994 | 23 | #include <net/mptcp.h> |
4596a2c1 | 24 | #include <uapi/linux/mptcp.h> |
2303f994 | 25 | #include "protocol.h" |
fc518953 FW |
26 | #include "mib.h" |
27 | ||
0918e34b GT |
28 | #include <trace/events/mptcp.h> |
29 | ||
b19bc294 PA |
30 | static void mptcp_subflow_ops_undo_override(struct sock *ssk); |
31 | ||
fc518953 FW |
32 | static void SUBFLOW_REQ_INC_STATS(struct request_sock *req, |
33 | enum linux_mptcp_mib_field field) | |
34 | { | |
35 | MPTCP_INC_STATS(sock_net(req_to_sk(req)), field); | |
36 | } | |
2303f994 | 37 | |
79c0949e PK |
38 | static void subflow_req_destructor(struct request_sock *req) |
39 | { | |
40 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); | |
41 | ||
42 | pr_debug("subflow_req=%p", subflow_req); | |
43 | ||
8fd4de12 PA |
44 | if (subflow_req->msk) |
45 | sock_put((struct sock *)subflow_req->msk); | |
46 | ||
2c5ebd00 | 47 | mptcp_token_destroy_request(req); |
79c0949e PK |
48 | tcp_request_sock_ops.destructor(req); |
49 | } | |
50 | ||
f296234c PK |
51 | static void subflow_generate_hmac(u64 key1, u64 key2, u32 nonce1, u32 nonce2, |
52 | void *hmac) | |
53 | { | |
54 | u8 msg[8]; | |
55 | ||
56 | put_unaligned_be32(nonce1, &msg[0]); | |
57 | put_unaligned_be32(nonce2, &msg[4]); | |
58 | ||
59 | mptcp_crypto_hmac_sha(key1, key2, msg, 8, hmac); | |
60 | } | |
61 | ||
4cf8b7e4 PA |
62 | static bool mptcp_can_accept_new_subflow(const struct mptcp_sock *msk) |
63 | { | |
64 | return mptcp_is_fully_established((void *)msk) && | |
65 | READ_ONCE(msk->pm.accept_subflow); | |
66 | } | |
67 | ||
f296234c | 68 | /* validate received token and create truncated hmac and nonce for SYN-ACK */ |
ec20e143 GT |
69 | static void subflow_req_create_thmac(struct mptcp_subflow_request_sock *subflow_req) |
70 | { | |
71 | struct mptcp_sock *msk = subflow_req->msk; | |
72 | u8 hmac[SHA256_DIGEST_SIZE]; | |
73 | ||
74 | get_random_bytes(&subflow_req->local_nonce, sizeof(u32)); | |
75 | ||
76 | subflow_generate_hmac(msk->local_key, msk->remote_key, | |
77 | subflow_req->local_nonce, | |
78 | subflow_req->remote_nonce, hmac); | |
79 | ||
80 | subflow_req->thmac = get_unaligned_be64(hmac); | |
81 | } | |
82 | ||
b5e2e42f | 83 | static struct mptcp_sock *subflow_token_join_request(struct request_sock *req) |
f296234c PK |
84 | { |
85 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); | |
f296234c PK |
86 | struct mptcp_sock *msk; |
87 | int local_id; | |
88 | ||
ea1300b9 | 89 | msk = mptcp_token_get_sock(sock_net(req_to_sk(req)), subflow_req->token); |
f296234c | 90 | if (!msk) { |
fc518953 | 91 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINNOTOKEN); |
8fd4de12 | 92 | return NULL; |
f296234c PK |
93 | } |
94 | ||
95 | local_id = mptcp_pm_get_local_id(msk, (struct sock_common *)req); | |
96 | if (local_id < 0) { | |
97 | sock_put((struct sock *)msk); | |
8fd4de12 | 98 | return NULL; |
f296234c PK |
99 | } |
100 | subflow_req->local_id = local_id; | |
101 | ||
8fd4de12 | 102 | return msk; |
f296234c PK |
103 | } |
104 | ||
d8b59efa | 105 | static void subflow_init_req(struct request_sock *req, const struct sock *sk_listener) |
cec37a6e | 106 | { |
cec37a6e | 107 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); |
cec37a6e PK |
108 | |
109 | subflow_req->mp_capable = 0; | |
f296234c | 110 | subflow_req->mp_join = 0; |
06fe1719 | 111 | subflow_req->csum_reqd = mptcp_is_checksum_enabled(sock_net(sk_listener)); |
bab6b88e | 112 | subflow_req->allow_join_id0 = mptcp_allow_join_id0(sock_net(sk_listener)); |
8fd4de12 | 113 | subflow_req->msk = NULL; |
2c5ebd00 | 114 | mptcp_token_init_request(req); |
78d8b7bc FW |
115 | } |
116 | ||
5bc56388 GT |
117 | static bool subflow_use_different_sport(struct mptcp_sock *msk, const struct sock *sk) |
118 | { | |
119 | return inet_sk(sk)->inet_sport != inet_sk((struct sock *)msk)->inet_sport; | |
120 | } | |
121 | ||
dc87efdb FW |
122 | static void subflow_add_reset_reason(struct sk_buff *skb, u8 reason) |
123 | { | |
124 | struct mptcp_ext *mpext = skb_ext_add(skb, SKB_EXT_MPTCP); | |
125 | ||
126 | if (mpext) { | |
127 | memset(mpext, 0, sizeof(*mpext)); | |
128 | mpext->reset_reason = reason; | |
129 | } | |
130 | } | |
131 | ||
3ecfbe3e FW |
132 | /* Init mptcp request socket. |
133 | * | |
134 | * Returns an error code if a JOIN has failed and a TCP reset | |
135 | * should be sent. | |
136 | */ | |
d8b59efa PA |
137 | static int subflow_check_req(struct request_sock *req, |
138 | const struct sock *sk_listener, | |
139 | struct sk_buff *skb) | |
78d8b7bc FW |
140 | { |
141 | struct mptcp_subflow_context *listener = mptcp_subflow_ctx(sk_listener); | |
142 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); | |
143 | struct mptcp_options_received mp_opt; | |
74c7dfbe | 144 | bool opt_mp_capable, opt_mp_join; |
78d8b7bc FW |
145 | |
146 | pr_debug("subflow_req=%p, listener=%p", subflow_req, listener); | |
147 | ||
d8b59efa PA |
148 | #ifdef CONFIG_TCP_MD5SIG |
149 | /* no MPTCP if MD5SIG is enabled on this socket or we may run out of | |
150 | * TCP option space. | |
151 | */ | |
152 | if (rcu_access_pointer(tcp_sk(sk_listener)->md5sig_info)) | |
153 | return -EINVAL; | |
154 | #endif | |
78d8b7bc | 155 | |
c863225b | 156 | mptcp_get_options(sk_listener, skb, &mp_opt); |
78d8b7bc | 157 | |
74c7dfbe PA |
158 | opt_mp_capable = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPC); |
159 | opt_mp_join = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ); | |
160 | if (opt_mp_capable) { | |
fc518953 FW |
161 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVE); |
162 | ||
74c7dfbe | 163 | if (opt_mp_join) |
3ecfbe3e | 164 | return 0; |
74c7dfbe | 165 | } else if (opt_mp_join) { |
fc518953 FW |
166 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINSYNRX); |
167 | } | |
f296234c | 168 | |
74c7dfbe | 169 | if (opt_mp_capable && listener->request_mptcp) { |
c68a0cd1 | 170 | int err, retries = MPTCP_TOKEN_MAX_RETRIES; |
535fb815 | 171 | |
c83a47e5 | 172 | subflow_req->ssn_offset = TCP_SKB_CB(skb)->seq; |
535fb815 FW |
173 | again: |
174 | do { | |
175 | get_random_bytes(&subflow_req->local_key, sizeof(subflow_req->local_key)); | |
176 | } while (subflow_req->local_key == 0); | |
79c0949e | 177 | |
c83a47e5 FW |
178 | if (unlikely(req->syncookie)) { |
179 | mptcp_crypto_key_sha(subflow_req->local_key, | |
180 | &subflow_req->token, | |
181 | &subflow_req->idsn); | |
182 | if (mptcp_token_exists(subflow_req->token)) { | |
183 | if (retries-- > 0) | |
184 | goto again; | |
a16195e3 | 185 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_TOKENFALLBACKINIT); |
c83a47e5 FW |
186 | } else { |
187 | subflow_req->mp_capable = 1; | |
188 | } | |
3ecfbe3e | 189 | return 0; |
c83a47e5 FW |
190 | } |
191 | ||
79c0949e PK |
192 | err = mptcp_token_new_request(req); |
193 | if (err == 0) | |
194 | subflow_req->mp_capable = 1; | |
535fb815 FW |
195 | else if (retries-- > 0) |
196 | goto again; | |
a16195e3 PA |
197 | else |
198 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_TOKENFALLBACKINIT); | |
79c0949e | 199 | |
74c7dfbe | 200 | } else if (opt_mp_join && listener->request_mptcp) { |
ec3edaa7 | 201 | subflow_req->ssn_offset = TCP_SKB_CB(skb)->seq; |
f296234c | 202 | subflow_req->mp_join = 1; |
cfde141e PA |
203 | subflow_req->backup = mp_opt.backup; |
204 | subflow_req->remote_id = mp_opt.join_id; | |
205 | subflow_req->token = mp_opt.token; | |
206 | subflow_req->remote_nonce = mp_opt.nonce; | |
b5e2e42f | 207 | subflow_req->msk = subflow_token_join_request(req); |
9466a1cc | 208 | |
3ecfbe3e | 209 | /* Can't fall back to TCP in this case. */ |
dc87efdb FW |
210 | if (!subflow_req->msk) { |
211 | subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP); | |
3ecfbe3e | 212 | return -EPERM; |
dc87efdb | 213 | } |
3ecfbe3e | 214 | |
5bc56388 GT |
215 | if (subflow_use_different_sport(subflow_req->msk, sk_listener)) { |
216 | pr_debug("syn inet_sport=%d %d", | |
217 | ntohs(inet_sk(sk_listener)->inet_sport), | |
218 | ntohs(inet_sk((struct sock *)subflow_req->msk)->inet_sport)); | |
219 | if (!mptcp_pm_sport_in_anno_list(subflow_req->msk, sk_listener)) { | |
2fbdd9ea | 220 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MISMATCHPORTSYNRX); |
5bc56388 GT |
221 | return -EPERM; |
222 | } | |
2fbdd9ea | 223 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINPORTSYNRX); |
5bc56388 GT |
224 | } |
225 | ||
ec20e143 GT |
226 | subflow_req_create_thmac(subflow_req); |
227 | ||
3ecfbe3e | 228 | if (unlikely(req->syncookie)) { |
9466a1cc FW |
229 | if (mptcp_can_accept_new_subflow(subflow_req->msk)) |
230 | subflow_init_req_cookie_join_save(subflow_req, skb); | |
8547ea5f JW |
231 | else |
232 | return -EPERM; | |
9466a1cc FW |
233 | } |
234 | ||
8fd4de12 PA |
235 | pr_debug("token=%u, remote_nonce=%u msk=%p", subflow_req->token, |
236 | subflow_req->remote_nonce, subflow_req->msk); | |
cec37a6e | 237 | } |
3ecfbe3e FW |
238 | |
239 | return 0; | |
cec37a6e PK |
240 | } |
241 | ||
c83a47e5 FW |
242 | int mptcp_subflow_init_cookie_req(struct request_sock *req, |
243 | const struct sock *sk_listener, | |
244 | struct sk_buff *skb) | |
245 | { | |
246 | struct mptcp_subflow_context *listener = mptcp_subflow_ctx(sk_listener); | |
247 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); | |
248 | struct mptcp_options_received mp_opt; | |
74c7dfbe | 249 | bool opt_mp_capable, opt_mp_join; |
c83a47e5 FW |
250 | int err; |
251 | ||
d8b59efa | 252 | subflow_init_req(req, sk_listener); |
c863225b | 253 | mptcp_get_options(sk_listener, skb, &mp_opt); |
c83a47e5 | 254 | |
74c7dfbe PA |
255 | opt_mp_capable = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPC); |
256 | opt_mp_join = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ); | |
257 | if (opt_mp_capable && opt_mp_join) | |
c83a47e5 FW |
258 | return -EINVAL; |
259 | ||
74c7dfbe | 260 | if (opt_mp_capable && listener->request_mptcp) { |
c83a47e5 FW |
261 | if (mp_opt.sndr_key == 0) |
262 | return -EINVAL; | |
263 | ||
264 | subflow_req->local_key = mp_opt.rcvr_key; | |
265 | err = mptcp_token_new_request(req); | |
266 | if (err) | |
267 | return err; | |
268 | ||
269 | subflow_req->mp_capable = 1; | |
270 | subflow_req->ssn_offset = TCP_SKB_CB(skb)->seq - 1; | |
74c7dfbe | 271 | } else if (opt_mp_join && listener->request_mptcp) { |
9466a1cc FW |
272 | if (!mptcp_token_join_cookie_init_state(subflow_req, skb)) |
273 | return -EINVAL; | |
274 | ||
8547ea5f | 275 | subflow_req->mp_join = 1; |
9466a1cc | 276 | subflow_req->ssn_offset = TCP_SKB_CB(skb)->seq - 1; |
c83a47e5 FW |
277 | } |
278 | ||
279 | return 0; | |
280 | } | |
281 | EXPORT_SYMBOL_GPL(mptcp_subflow_init_cookie_req); | |
282 | ||
7ea851d1 FW |
283 | static struct dst_entry *subflow_v4_route_req(const struct sock *sk, |
284 | struct sk_buff *skb, | |
285 | struct flowi *fl, | |
286 | struct request_sock *req) | |
cec37a6e | 287 | { |
7ea851d1 | 288 | struct dst_entry *dst; |
3ecfbe3e | 289 | int err; |
7ea851d1 | 290 | |
cec37a6e | 291 | tcp_rsk(req)->is_mptcp = 1; |
d8b59efa | 292 | subflow_init_req(req, sk); |
cec37a6e | 293 | |
7ea851d1 FW |
294 | dst = tcp_request_sock_ipv4_ops.route_req(sk, skb, fl, req); |
295 | if (!dst) | |
296 | return NULL; | |
cec37a6e | 297 | |
d8b59efa | 298 | err = subflow_check_req(req, sk, skb); |
3ecfbe3e FW |
299 | if (err == 0) |
300 | return dst; | |
cec37a6e | 301 | |
3ecfbe3e FW |
302 | dst_release(dst); |
303 | if (!req->syncookie) | |
304 | tcp_request_sock_ops.send_reset(sk, skb); | |
305 | return NULL; | |
cec37a6e PK |
306 | } |
307 | ||
308 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
7ea851d1 FW |
309 | static struct dst_entry *subflow_v6_route_req(const struct sock *sk, |
310 | struct sk_buff *skb, | |
311 | struct flowi *fl, | |
312 | struct request_sock *req) | |
cec37a6e | 313 | { |
7ea851d1 | 314 | struct dst_entry *dst; |
3ecfbe3e | 315 | int err; |
7ea851d1 | 316 | |
cec37a6e | 317 | tcp_rsk(req)->is_mptcp = 1; |
d8b59efa | 318 | subflow_init_req(req, sk); |
cec37a6e | 319 | |
7ea851d1 FW |
320 | dst = tcp_request_sock_ipv6_ops.route_req(sk, skb, fl, req); |
321 | if (!dst) | |
322 | return NULL; | |
cec37a6e | 323 | |
d8b59efa | 324 | err = subflow_check_req(req, sk, skb); |
3ecfbe3e FW |
325 | if (err == 0) |
326 | return dst; | |
327 | ||
328 | dst_release(dst); | |
329 | if (!req->syncookie) | |
330 | tcp6_request_sock_ops.send_reset(sk, skb); | |
331 | return NULL; | |
cec37a6e PK |
332 | } |
333 | #endif | |
334 | ||
ec3edaa7 PK |
335 | /* validate received truncated hmac and create hmac for third ACK */ |
336 | static bool subflow_thmac_valid(struct mptcp_subflow_context *subflow) | |
337 | { | |
bd697222 | 338 | u8 hmac[SHA256_DIGEST_SIZE]; |
ec3edaa7 PK |
339 | u64 thmac; |
340 | ||
341 | subflow_generate_hmac(subflow->remote_key, subflow->local_key, | |
342 | subflow->remote_nonce, subflow->local_nonce, | |
343 | hmac); | |
344 | ||
345 | thmac = get_unaligned_be64(hmac); | |
346 | pr_debug("subflow=%p, token=%u, thmac=%llu, subflow->thmac=%llu\n", | |
347 | subflow, subflow->token, | |
348 | (unsigned long long)thmac, | |
349 | (unsigned long long)subflow->thmac); | |
350 | ||
351 | return thmac == subflow->thmac; | |
352 | } | |
353 | ||
d5824847 PA |
354 | void mptcp_subflow_reset(struct sock *ssk) |
355 | { | |
0e4f35d7 PA |
356 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
357 | struct sock *sk = subflow->conn; | |
358 | ||
ab82e996 FW |
359 | /* must hold: tcp_done() could drop last reference on parent */ |
360 | sock_hold(sk); | |
361 | ||
d5824847 PA |
362 | tcp_set_state(ssk, TCP_CLOSE); |
363 | tcp_send_active_reset(ssk, GFP_ATOMIC); | |
364 | tcp_done(ssk); | |
0e4f35d7 PA |
365 | if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags) && |
366 | schedule_work(&mptcp_sk(sk)->work)) | |
ab82e996 FW |
367 | return; /* worker will put sk for us */ |
368 | ||
369 | sock_put(sk); | |
d5824847 PA |
370 | } |
371 | ||
5bc56388 GT |
372 | static bool subflow_use_different_dport(struct mptcp_sock *msk, const struct sock *sk) |
373 | { | |
374 | return inet_sk(sk)->inet_dport != inet_sk((struct sock *)msk)->inet_dport; | |
375 | } | |
376 | ||
490274b4 PA |
377 | void __mptcp_set_connected(struct sock *sk) |
378 | { | |
379 | if (sk->sk_state == TCP_SYN_SENT) { | |
380 | inet_sk_state_store(sk, TCP_ESTABLISHED); | |
381 | sk->sk_state_change(sk); | |
382 | } | |
383 | } | |
384 | ||
385 | static void mptcp_set_connected(struct sock *sk) | |
386 | { | |
387 | mptcp_data_lock(sk); | |
388 | if (!sock_owned_by_user(sk)) | |
389 | __mptcp_set_connected(sk); | |
390 | else | |
391 | set_bit(MPTCP_CONNECTED, &mptcp_sk(sk)->flags); | |
392 | mptcp_data_unlock(sk); | |
393 | } | |
394 | ||
cec37a6e PK |
395 | static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb) |
396 | { | |
397 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
cfde141e | 398 | struct mptcp_options_received mp_opt; |
c3c123d1 | 399 | struct sock *parent = subflow->conn; |
cec37a6e PK |
400 | |
401 | subflow->icsk_af_ops->sk_rx_dst_set(sk, skb); | |
402 | ||
263e1201 PA |
403 | /* be sure no special action on any packet other than syn-ack */ |
404 | if (subflow->conn_finished) | |
405 | return; | |
406 | ||
5cf92bba | 407 | mptcp_propagate_sndbuf(parent, sk); |
b0977bb2 | 408 | subflow->rel_write_seq = 1; |
263e1201 | 409 | subflow->conn_finished = 1; |
e1ff9e82 DC |
410 | subflow->ssn_offset = TCP_SKB_CB(skb)->seq; |
411 | pr_debug("subflow=%p synack seq=%x", subflow, subflow->ssn_offset); | |
263e1201 | 412 | |
c863225b | 413 | mptcp_get_options(sk, skb, &mp_opt); |
fa25e815 | 414 | if (subflow->request_mptcp) { |
74c7dfbe | 415 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) { |
fa25e815 PA |
416 | MPTCP_INC_STATS(sock_net(sk), |
417 | MPTCP_MIB_MPCAPABLEACTIVEFALLBACK); | |
418 | mptcp_do_fallback(sk); | |
419 | pr_fallback(mptcp_sk(subflow->conn)); | |
420 | goto fallback; | |
421 | } | |
422 | ||
74c7dfbe | 423 | if (mp_opt.suboptions & OPTION_MPTCP_CSUMREQD) |
06251181 | 424 | WRITE_ONCE(mptcp_sk(parent)->csum_enabled, true); |
df377be3 GT |
425 | if (mp_opt.deny_join_id0) |
426 | WRITE_ONCE(mptcp_sk(parent)->pm.remote_deny_join_id0, true); | |
263e1201 PA |
427 | subflow->mp_capable = 1; |
428 | subflow->can_ack = 1; | |
cfde141e | 429 | subflow->remote_key = mp_opt.sndr_key; |
263e1201 PA |
430 | pr_debug("subflow=%p, remote_key=%llu", subflow, |
431 | subflow->remote_key); | |
5695eb88 | 432 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVEACK); |
fa25e815 | 433 | mptcp_finish_connect(sk); |
490274b4 | 434 | mptcp_set_connected(parent); |
fa25e815 PA |
435 | } else if (subflow->request_join) { |
436 | u8 hmac[SHA256_DIGEST_SIZE]; | |
437 | ||
74c7dfbe | 438 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ)) { |
dc87efdb | 439 | subflow->reset_reason = MPTCP_RST_EMPTCP; |
fa25e815 | 440 | goto do_reset; |
dc87efdb | 441 | } |
fa25e815 | 442 | |
0460ce22 | 443 | subflow->backup = mp_opt.backup; |
cfde141e PA |
444 | subflow->thmac = mp_opt.thmac; |
445 | subflow->remote_nonce = mp_opt.nonce; | |
0460ce22 PA |
446 | pr_debug("subflow=%p, thmac=%llu, remote_nonce=%u backup=%d", |
447 | subflow, subflow->thmac, subflow->remote_nonce, | |
448 | subflow->backup); | |
263e1201 | 449 | |
ec3edaa7 | 450 | if (!subflow_thmac_valid(subflow)) { |
fc518953 | 451 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINACKMAC); |
dc87efdb | 452 | subflow->reset_reason = MPTCP_RST_EMPTCP; |
ec3edaa7 PK |
453 | goto do_reset; |
454 | } | |
455 | ||
0a4d8e96 JW |
456 | if (!mptcp_finish_join(sk)) |
457 | goto do_reset; | |
458 | ||
ec3edaa7 PK |
459 | subflow_generate_hmac(subflow->local_key, subflow->remote_key, |
460 | subflow->local_nonce, | |
461 | subflow->remote_nonce, | |
bd697222 | 462 | hmac); |
bd697222 | 463 | memcpy(subflow->hmac, hmac, MPTCPOPT_HMAC_LEN); |
ec3edaa7 | 464 | |
fa25e815 | 465 | subflow->mp_join = 1; |
fc518953 | 466 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX); |
5bc56388 GT |
467 | |
468 | if (subflow_use_different_dport(mptcp_sk(parent), sk)) { | |
469 | pr_debug("synack inet_dport=%d %d", | |
470 | ntohs(inet_sk(sk)->inet_dport), | |
471 | ntohs(inet_sk(parent)->inet_dport)); | |
2fbdd9ea | 472 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINPORTSYNACKRX); |
5bc56388 | 473 | } |
fa25e815 PA |
474 | } else if (mptcp_check_fallback(sk)) { |
475 | fallback: | |
476 | mptcp_rcv_space_init(mptcp_sk(parent), sk); | |
490274b4 | 477 | mptcp_set_connected(parent); |
cec37a6e | 478 | } |
fa25e815 PA |
479 | return; |
480 | ||
481 | do_reset: | |
dc87efdb | 482 | subflow->reset_transient = 0; |
d5824847 | 483 | mptcp_subflow_reset(sk); |
cec37a6e PK |
484 | } |
485 | ||
08b8d080 FW |
486 | struct request_sock_ops mptcp_subflow_request_sock_ops; |
487 | EXPORT_SYMBOL_GPL(mptcp_subflow_request_sock_ops); | |
cec37a6e PK |
488 | static struct tcp_request_sock_ops subflow_request_sock_ipv4_ops; |
489 | ||
490 | static int subflow_v4_conn_request(struct sock *sk, struct sk_buff *skb) | |
491 | { | |
492 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
493 | ||
494 | pr_debug("subflow=%p", subflow); | |
495 | ||
496 | /* Never answer to SYNs sent to broadcast or multicast */ | |
497 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) | |
498 | goto drop; | |
499 | ||
08b8d080 | 500 | return tcp_conn_request(&mptcp_subflow_request_sock_ops, |
cec37a6e PK |
501 | &subflow_request_sock_ipv4_ops, |
502 | sk, skb); | |
503 | drop: | |
504 | tcp_listendrop(sk); | |
505 | return 0; | |
506 | } | |
507 | ||
508 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
509 | static struct tcp_request_sock_ops subflow_request_sock_ipv6_ops; | |
510 | static struct inet_connection_sock_af_ops subflow_v6_specific; | |
511 | static struct inet_connection_sock_af_ops subflow_v6m_specific; | |
b19bc294 | 512 | static struct proto tcpv6_prot_override; |
cec37a6e PK |
513 | |
514 | static int subflow_v6_conn_request(struct sock *sk, struct sk_buff *skb) | |
515 | { | |
516 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
517 | ||
518 | pr_debug("subflow=%p", subflow); | |
519 | ||
520 | if (skb->protocol == htons(ETH_P_IP)) | |
521 | return subflow_v4_conn_request(sk, skb); | |
522 | ||
523 | if (!ipv6_unicast_destination(skb)) | |
524 | goto drop; | |
525 | ||
dcc32f4f JK |
526 | if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) { |
527 | __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS); | |
528 | return 0; | |
529 | } | |
530 | ||
08b8d080 | 531 | return tcp_conn_request(&mptcp_subflow_request_sock_ops, |
cec37a6e PK |
532 | &subflow_request_sock_ipv6_ops, sk, skb); |
533 | ||
534 | drop: | |
535 | tcp_listendrop(sk); | |
536 | return 0; /* don't send reset */ | |
537 | } | |
538 | #endif | |
539 | ||
f296234c PK |
540 | /* validate hmac received in third ACK */ |
541 | static bool subflow_hmac_valid(const struct request_sock *req, | |
cfde141e | 542 | const struct mptcp_options_received *mp_opt) |
f296234c PK |
543 | { |
544 | const struct mptcp_subflow_request_sock *subflow_req; | |
bd697222 | 545 | u8 hmac[SHA256_DIGEST_SIZE]; |
f296234c | 546 | struct mptcp_sock *msk; |
f296234c PK |
547 | |
548 | subflow_req = mptcp_subflow_rsk(req); | |
8fd4de12 | 549 | msk = subflow_req->msk; |
f296234c PK |
550 | if (!msk) |
551 | return false; | |
552 | ||
553 | subflow_generate_hmac(msk->remote_key, msk->local_key, | |
554 | subflow_req->remote_nonce, | |
555 | subflow_req->local_nonce, hmac); | |
556 | ||
8fd4de12 | 557 | return !crypto_memneq(hmac, mp_opt->hmac, MPTCPOPT_HMAC_LEN); |
f296234c PK |
558 | } |
559 | ||
df1036da FW |
560 | static void mptcp_sock_destruct(struct sock *sk) |
561 | { | |
562 | /* if new mptcp socket isn't accepted, it is free'd | |
563 | * from the tcp listener sockets request queue, linked | |
564 | * from req->sk. The tcp socket is released. | |
565 | * This calls the ULP release function which will | |
566 | * also remove the mptcp socket, via | |
567 | * sock_put(ctx->conn). | |
568 | * | |
7ee24926 PA |
569 | * Problem is that the mptcp socket will be in |
570 | * ESTABLISHED state and will not have the SOCK_DEAD flag. | |
df1036da FW |
571 | * Both result in warnings from inet_sock_destruct. |
572 | */ | |
578c18ef | 573 | if ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { |
df1036da FW |
574 | sk->sk_state = TCP_CLOSE; |
575 | WARN_ON_ONCE(sk->sk_socket); | |
576 | sock_orphan(sk); | |
577 | } | |
578 | ||
5c8c1640 | 579 | mptcp_destroy_common(mptcp_sk(sk)); |
df1036da FW |
580 | inet_sock_destruct(sk); |
581 | } | |
582 | ||
9f5ca6a5 FW |
583 | static void mptcp_force_close(struct sock *sk) |
584 | { | |
490274b4 | 585 | /* the msk is not yet exposed to user-space */ |
9f5ca6a5 FW |
586 | inet_sk_state_store(sk, TCP_CLOSE); |
587 | sk_common_release(sk); | |
588 | } | |
589 | ||
4c8941de PA |
590 | static void subflow_ulp_fallback(struct sock *sk, |
591 | struct mptcp_subflow_context *old_ctx) | |
592 | { | |
593 | struct inet_connection_sock *icsk = inet_csk(sk); | |
594 | ||
595 | mptcp_subflow_tcp_fallback(sk, old_ctx); | |
596 | icsk->icsk_ulp_ops = NULL; | |
597 | rcu_assign_pointer(icsk->icsk_ulp_data, NULL); | |
598 | tcp_sk(sk)->is_mptcp = 0; | |
b19bc294 PA |
599 | |
600 | mptcp_subflow_ops_undo_override(sk); | |
4c8941de PA |
601 | } |
602 | ||
39884604 PA |
603 | static void subflow_drop_ctx(struct sock *ssk) |
604 | { | |
605 | struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(ssk); | |
606 | ||
607 | if (!ctx) | |
608 | return; | |
609 | ||
610 | subflow_ulp_fallback(ssk, ctx); | |
611 | if (ctx->conn) | |
612 | sock_put(ctx->conn); | |
613 | ||
614 | kfree_rcu(ctx, rcu); | |
615 | } | |
616 | ||
b93df08c PA |
617 | void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, |
618 | struct mptcp_options_received *mp_opt) | |
619 | { | |
620 | struct mptcp_sock *msk = mptcp_sk(subflow->conn); | |
621 | ||
622 | subflow->remote_key = mp_opt->sndr_key; | |
623 | subflow->fully_established = 1; | |
624 | subflow->can_ack = 1; | |
625 | WRITE_ONCE(msk->fully_established, true); | |
626 | } | |
627 | ||
cec37a6e PK |
628 | static struct sock *subflow_syn_recv_sock(const struct sock *sk, |
629 | struct sk_buff *skb, | |
630 | struct request_sock *req, | |
631 | struct dst_entry *dst, | |
632 | struct request_sock *req_unhash, | |
633 | bool *own_req) | |
634 | { | |
635 | struct mptcp_subflow_context *listener = mptcp_subflow_ctx(sk); | |
cc7972ea | 636 | struct mptcp_subflow_request_sock *subflow_req; |
cfde141e | 637 | struct mptcp_options_received mp_opt; |
9e365ff5 | 638 | bool fallback, fallback_is_fatal; |
58b09919 | 639 | struct sock *new_msk = NULL; |
cec37a6e PK |
640 | struct sock *child; |
641 | ||
642 | pr_debug("listener=%p, req=%p, conn=%p", listener, req, listener->conn); | |
643 | ||
74c7dfbe | 644 | /* After child creation we must look for MPC even when options |
9e365ff5 | 645 | * are not parsed |
cfde141e | 646 | */ |
74c7dfbe | 647 | mp_opt.suboptions = 0; |
9e365ff5 PA |
648 | |
649 | /* hopefully temporary handling for MP_JOIN+syncookie */ | |
650 | subflow_req = mptcp_subflow_rsk(req); | |
b7514694 | 651 | fallback_is_fatal = tcp_rsk(req)->is_mptcp && subflow_req->mp_join; |
9e365ff5 PA |
652 | fallback = !tcp_rsk(req)->is_mptcp; |
653 | if (fallback) | |
ae2dd716 FW |
654 | goto create_child; |
655 | ||
d22f4988 | 656 | /* if the sk is MP_CAPABLE, we try to fetch the client key */ |
cc7972ea | 657 | if (subflow_req->mp_capable) { |
06f9a435 PA |
658 | /* we can receive and accept an in-window, out-of-order pkt, |
659 | * which may not carry the MP_CAPABLE opt even on mptcp enabled | |
660 | * paths: always try to extract the peer key, and fallback | |
661 | * for packets missing it. | |
662 | * Even OoO DSS packets coming legitly after dropped or | |
663 | * reordered MPC will cause fallback, but we don't have other | |
664 | * options. | |
665 | */ | |
c863225b | 666 | mptcp_get_options(sk, skb, &mp_opt); |
74c7dfbe | 667 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) { |
4c8941de | 668 | fallback = true; |
58b09919 | 669 | goto create_child; |
d22f4988 | 670 | } |
58b09919 | 671 | |
cfde141e | 672 | new_msk = mptcp_sk_clone(listener->conn, &mp_opt, req); |
58b09919 | 673 | if (!new_msk) |
4c8941de | 674 | fallback = true; |
f296234c | 675 | } else if (subflow_req->mp_join) { |
c863225b | 676 | mptcp_get_options(sk, skb, &mp_opt); |
74c7dfbe PA |
677 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ) || |
678 | !subflow_hmac_valid(req, &mp_opt) || | |
d3ab7885 | 679 | !mptcp_can_accept_new_subflow(subflow_req->msk)) { |
fc518953 | 680 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKMAC); |
9e365ff5 | 681 | fallback = true; |
fc518953 | 682 | } |
cc7972ea | 683 | } |
cec37a6e | 684 | |
d22f4988 | 685 | create_child: |
cec37a6e PK |
686 | child = listener->icsk_af_ops->syn_recv_sock(sk, skb, req, dst, |
687 | req_unhash, own_req); | |
688 | ||
689 | if (child && *own_req) { | |
79c0949e PK |
690 | struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(child); |
691 | ||
90bf4513 PA |
692 | tcp_rsk(req)->drop_req = false; |
693 | ||
4c8941de PA |
694 | /* we need to fallback on ctx allocation failure and on pre-reqs |
695 | * checking above. In the latter scenario we additionally need | |
696 | * to reset the context to non MPTCP status. | |
79c0949e | 697 | */ |
4c8941de | 698 | if (!ctx || fallback) { |
dc87efdb FW |
699 | if (fallback_is_fatal) { |
700 | subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP); | |
729cd643 | 701 | goto dispose_child; |
dc87efdb | 702 | } |
4c8941de | 703 | |
39884604 | 704 | subflow_drop_ctx(child); |
58b09919 | 705 | goto out; |
f296234c | 706 | } |
79c0949e | 707 | |
df00b087 FW |
708 | /* ssk inherits options of listener sk */ |
709 | ctx->setsockopt_seq = listener->setsockopt_seq; | |
710 | ||
79c0949e | 711 | if (ctx->mp_capable) { |
b93df08c PA |
712 | /* this can't race with mptcp_close(), as the msk is |
713 | * not yet exposted to user-space | |
714 | */ | |
715 | inet_sk_state_store((void *)new_msk, TCP_ESTABLISHED); | |
716 | ||
5b950ff4 PA |
717 | /* record the newly created socket as the first msk |
718 | * subflow, but don't link it yet into conn_list | |
719 | */ | |
0397c6d8 PA |
720 | WRITE_ONCE(mptcp_sk(new_msk)->first, child); |
721 | ||
58b09919 PA |
722 | /* new mpc subflow takes ownership of the newly |
723 | * created mptcp socket | |
724 | */ | |
df1036da | 725 | new_msk->sk_destruct = mptcp_sock_destruct; |
df00b087 | 726 | mptcp_sk(new_msk)->setsockopt_seq = ctx->setsockopt_seq; |
6c714f1b | 727 | mptcp_pm_new_connection(mptcp_sk(new_msk), child, 1); |
2c5ebd00 | 728 | mptcp_token_accept(subflow_req, mptcp_sk(new_msk)); |
58b09919 PA |
729 | ctx->conn = new_msk; |
730 | new_msk = NULL; | |
fca5c82c PA |
731 | |
732 | /* with OoO packets we can reach here without ingress | |
733 | * mpc option | |
734 | */ | |
74c7dfbe | 735 | if (mp_opt.suboptions & OPTIONS_MPTCP_MPC) |
b93df08c | 736 | mptcp_subflow_fully_established(ctx, &mp_opt); |
f296234c PK |
737 | } else if (ctx->mp_join) { |
738 | struct mptcp_sock *owner; | |
739 | ||
8fd4de12 | 740 | owner = subflow_req->msk; |
dc87efdb FW |
741 | if (!owner) { |
742 | subflow_add_reset_reason(skb, MPTCP_RST_EPROHIBIT); | |
729cd643 | 743 | goto dispose_child; |
dc87efdb | 744 | } |
f296234c | 745 | |
8fd4de12 PA |
746 | /* move the msk reference ownership to the subflow */ |
747 | subflow_req->msk = NULL; | |
f296234c | 748 | ctx->conn = (struct sock *)owner; |
5bc56388 GT |
749 | |
750 | if (subflow_use_different_sport(owner, sk)) { | |
751 | pr_debug("ack inet_sport=%d %d", | |
752 | ntohs(inet_sk(sk)->inet_sport), | |
753 | ntohs(inet_sk((struct sock *)owner)->inet_sport)); | |
2fbdd9ea GT |
754 | if (!mptcp_pm_sport_in_anno_list(owner, sk)) { |
755 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MISMATCHPORTACKRX); | |
9238e900 | 756 | goto dispose_child; |
2fbdd9ea GT |
757 | } |
758 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINPORTACKRX); | |
5bc56388 | 759 | } |
9238e900 GT |
760 | |
761 | if (!mptcp_finish_join(child)) | |
762 | goto dispose_child; | |
763 | ||
764 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKRX); | |
765 | tcp_rsk(req)->drop_req = true; | |
cec37a6e PK |
766 | } |
767 | } | |
768 | ||
58b09919 PA |
769 | out: |
770 | /* dispose of the left over mptcp master, if any */ | |
771 | if (unlikely(new_msk)) | |
9f5ca6a5 | 772 | mptcp_force_close(new_msk); |
4c8941de PA |
773 | |
774 | /* check for expected invariant - should never trigger, just help | |
775 | * catching eariler subtle bugs | |
776 | */ | |
ac2b47fb | 777 | WARN_ON_ONCE(child && *own_req && tcp_sk(child)->is_mptcp && |
4c8941de PA |
778 | (!mptcp_subflow_ctx(child) || |
779 | !mptcp_subflow_ctx(child)->conn)); | |
cec37a6e | 780 | return child; |
f296234c | 781 | |
729cd643 | 782 | dispose_child: |
39884604 | 783 | subflow_drop_ctx(child); |
729cd643 | 784 | tcp_rsk(req)->drop_req = true; |
729cd643 | 785 | inet_csk_prepare_for_destroy_sock(child); |
f296234c | 786 | tcp_done(child); |
97e61751 | 787 | req->rsk_ops->send_reset(sk, skb); |
729cd643 PA |
788 | |
789 | /* The last child reference will be released by the caller */ | |
790 | return child; | |
cec37a6e PK |
791 | } |
792 | ||
793 | static struct inet_connection_sock_af_ops subflow_specific; | |
b19bc294 | 794 | static struct proto tcp_prot_override; |
cec37a6e | 795 | |
648ef4b8 MM |
796 | enum mapping_status { |
797 | MAPPING_OK, | |
798 | MAPPING_INVALID, | |
799 | MAPPING_EMPTY, | |
e1ff9e82 DC |
800 | MAPPING_DATA_FIN, |
801 | MAPPING_DUMMY | |
648ef4b8 MM |
802 | }; |
803 | ||
61e71022 | 804 | static void dbg_bad_map(struct mptcp_subflow_context *subflow, u32 ssn) |
648ef4b8 | 805 | { |
61e71022 PA |
806 | pr_debug("Bad mapping: ssn=%d map_seq=%d map_data_len=%d", |
807 | ssn, subflow->map_subflow_seq, subflow->map_data_len); | |
648ef4b8 MM |
808 | } |
809 | ||
810 | static bool skb_is_fully_mapped(struct sock *ssk, struct sk_buff *skb) | |
811 | { | |
812 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
813 | unsigned int skb_consumed; | |
814 | ||
815 | skb_consumed = tcp_sk(ssk)->copied_seq - TCP_SKB_CB(skb)->seq; | |
816 | if (WARN_ON_ONCE(skb_consumed >= skb->len)) | |
817 | return true; | |
818 | ||
819 | return skb->len - skb_consumed <= subflow->map_data_len - | |
820 | mptcp_subflow_get_map_offset(subflow); | |
821 | } | |
822 | ||
823 | static bool validate_mapping(struct sock *ssk, struct sk_buff *skb) | |
824 | { | |
825 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
826 | u32 ssn = tcp_sk(ssk)->copied_seq - subflow->ssn_offset; | |
827 | ||
828 | if (unlikely(before(ssn, subflow->map_subflow_seq))) { | |
829 | /* Mapping covers data later in the subflow stream, | |
830 | * currently unsupported. | |
831 | */ | |
61e71022 | 832 | dbg_bad_map(subflow, ssn); |
648ef4b8 MM |
833 | return false; |
834 | } | |
835 | if (unlikely(!before(ssn, subflow->map_subflow_seq + | |
836 | subflow->map_data_len))) { | |
837 | /* Mapping does covers past subflow data, invalid */ | |
61e71022 | 838 | dbg_bad_map(subflow, ssn); |
648ef4b8 MM |
839 | return false; |
840 | } | |
841 | return true; | |
842 | } | |
843 | ||
dd8bcd17 PA |
844 | static enum mapping_status validate_data_csum(struct sock *ssk, struct sk_buff *skb, |
845 | bool csum_reqd) | |
846 | { | |
847 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
848 | struct csum_pseudo_header header; | |
849 | u32 offset, seq, delta; | |
850 | __wsum csum; | |
851 | int len; | |
852 | ||
853 | if (!csum_reqd) | |
854 | return MAPPING_OK; | |
855 | ||
856 | /* mapping already validated on previous traversal */ | |
857 | if (subflow->map_csum_len == subflow->map_data_len) | |
858 | return MAPPING_OK; | |
859 | ||
860 | /* traverse the receive queue, ensuring it contains a full | |
861 | * DSS mapping and accumulating the related csum. | |
862 | * Preserve the accoumlate csum across multiple calls, to compute | |
863 | * the csum only once | |
864 | */ | |
865 | delta = subflow->map_data_len - subflow->map_csum_len; | |
866 | for (;;) { | |
867 | seq = tcp_sk(ssk)->copied_seq + subflow->map_csum_len; | |
868 | offset = seq - TCP_SKB_CB(skb)->seq; | |
869 | ||
870 | /* if the current skb has not been accounted yet, csum its contents | |
871 | * up to the amount covered by the current DSS | |
872 | */ | |
873 | if (offset < skb->len) { | |
874 | __wsum csum; | |
875 | ||
876 | len = min(skb->len - offset, delta); | |
877 | csum = skb_checksum(skb, offset, len, 0); | |
878 | subflow->map_data_csum = csum_block_add(subflow->map_data_csum, csum, | |
879 | subflow->map_csum_len); | |
880 | ||
881 | delta -= len; | |
882 | subflow->map_csum_len += len; | |
883 | } | |
884 | if (delta == 0) | |
885 | break; | |
886 | ||
887 | if (skb_queue_is_last(&ssk->sk_receive_queue, skb)) { | |
888 | /* if this subflow is closed, the partial mapping | |
889 | * will be never completed; flush the pending skbs, so | |
890 | * that subflow_sched_work_if_closed() can kick in | |
891 | */ | |
892 | if (unlikely(ssk->sk_state == TCP_CLOSE)) | |
893 | while ((skb = skb_peek(&ssk->sk_receive_queue))) | |
894 | sk_eat_skb(ssk, skb); | |
895 | ||
896 | /* not enough data to validate the csum */ | |
897 | return MAPPING_EMPTY; | |
898 | } | |
899 | ||
900 | /* the DSS mapping for next skbs will be validated later, | |
901 | * when a get_mapping_status call will process such skb | |
902 | */ | |
903 | skb = skb->next; | |
904 | } | |
905 | ||
906 | /* note that 'map_data_len' accounts only for the carried data, does | |
907 | * not include the eventual seq increment due to the data fin, | |
908 | * while the pseudo header requires the original DSS data len, | |
909 | * including that | |
910 | */ | |
911 | header.data_seq = cpu_to_be64(subflow->map_seq); | |
912 | header.subflow_seq = htonl(subflow->map_subflow_seq); | |
913 | header.data_len = htons(subflow->map_data_len + subflow->map_data_fin); | |
914 | header.csum = 0; | |
915 | ||
916 | csum = csum_partial(&header, sizeof(header), subflow->map_data_csum); | |
fe3ab1cb GT |
917 | if (unlikely(csum_fold(csum))) { |
918 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DATACSUMERR); | |
478d7700 | 919 | subflow->send_mp_fail = 1; |
eb7f3365 | 920 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_MPFAILTX); |
dd8bcd17 | 921 | return subflow->mp_join ? MAPPING_INVALID : MAPPING_DUMMY; |
fe3ab1cb | 922 | } |
dd8bcd17 PA |
923 | |
924 | return MAPPING_OK; | |
925 | } | |
926 | ||
43b54c6e MM |
927 | static enum mapping_status get_mapping_status(struct sock *ssk, |
928 | struct mptcp_sock *msk) | |
648ef4b8 MM |
929 | { |
930 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
dd8bcd17 | 931 | bool csum_reqd = READ_ONCE(msk->csum_enabled); |
648ef4b8 MM |
932 | struct mptcp_ext *mpext; |
933 | struct sk_buff *skb; | |
934 | u16 data_len; | |
935 | u64 map_seq; | |
936 | ||
937 | skb = skb_peek(&ssk->sk_receive_queue); | |
938 | if (!skb) | |
939 | return MAPPING_EMPTY; | |
940 | ||
e1ff9e82 DC |
941 | if (mptcp_check_fallback(ssk)) |
942 | return MAPPING_DUMMY; | |
943 | ||
648ef4b8 MM |
944 | mpext = mptcp_get_ext(skb); |
945 | if (!mpext || !mpext->use_map) { | |
946 | if (!subflow->map_valid && !skb->len) { | |
947 | /* the TCP stack deliver 0 len FIN pkt to the receive | |
948 | * queue, that is the only 0len pkts ever expected here, | |
949 | * and we can admit no mapping only for 0 len pkts | |
950 | */ | |
951 | if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) | |
952 | WARN_ONCE(1, "0len seq %d:%d flags %x", | |
953 | TCP_SKB_CB(skb)->seq, | |
954 | TCP_SKB_CB(skb)->end_seq, | |
955 | TCP_SKB_CB(skb)->tcp_flags); | |
956 | sk_eat_skb(ssk, skb); | |
957 | return MAPPING_EMPTY; | |
958 | } | |
959 | ||
960 | if (!subflow->map_valid) | |
961 | return MAPPING_INVALID; | |
962 | ||
963 | goto validate_seq; | |
964 | } | |
965 | ||
0918e34b | 966 | trace_get_mapping_status(mpext); |
648ef4b8 MM |
967 | |
968 | data_len = mpext->data_len; | |
969 | if (data_len == 0) { | |
fc518953 | 970 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX); |
648ef4b8 MM |
971 | return MAPPING_INVALID; |
972 | } | |
973 | ||
974 | if (mpext->data_fin == 1) { | |
975 | if (data_len == 1) { | |
1a49b2c2 MM |
976 | bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq, |
977 | mpext->dsn64); | |
43b54c6e | 978 | pr_debug("DATA_FIN with no payload seq=%llu", mpext->data_seq); |
648ef4b8 MM |
979 | if (subflow->map_valid) { |
980 | /* A DATA_FIN might arrive in a DSS | |
981 | * option before the previous mapping | |
982 | * has been fully consumed. Continue | |
983 | * handling the existing mapping. | |
984 | */ | |
985 | skb_ext_del(skb, SKB_EXT_MPTCP); | |
986 | return MAPPING_OK; | |
987 | } else { | |
ef59b195 MM |
988 | if (updated && schedule_work(&msk->work)) |
989 | sock_hold((struct sock *)msk); | |
990 | ||
648ef4b8 MM |
991 | return MAPPING_DATA_FIN; |
992 | } | |
43b54c6e | 993 | } else { |
017512a0 | 994 | u64 data_fin_seq = mpext->data_seq + data_len - 1; |
1a49b2c2 MM |
995 | |
996 | /* If mpext->data_seq is a 32-bit value, data_fin_seq | |
997 | * must also be limited to 32 bits. | |
998 | */ | |
999 | if (!mpext->dsn64) | |
1000 | data_fin_seq &= GENMASK_ULL(31, 0); | |
1001 | ||
1002 | mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64); | |
1003 | pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d", | |
1004 | data_fin_seq, mpext->dsn64); | |
648ef4b8 MM |
1005 | } |
1006 | ||
1007 | /* Adjust for DATA_FIN using 1 byte of sequence space */ | |
1008 | data_len--; | |
1009 | } | |
1010 | ||
5957a890 | 1011 | map_seq = mptcp_expand_seq(READ_ONCE(msk->ack_seq), mpext->data_seq, mpext->dsn64); |
37198e93 | 1012 | WRITE_ONCE(mptcp_sk(subflow->conn)->use_64bit_ack, !!mpext->dsn64); |
648ef4b8 MM |
1013 | |
1014 | if (subflow->map_valid) { | |
1015 | /* Allow replacing only with an identical map */ | |
1016 | if (subflow->map_seq == map_seq && | |
1017 | subflow->map_subflow_seq == mpext->subflow_seq && | |
dd8bcd17 PA |
1018 | subflow->map_data_len == data_len && |
1019 | subflow->map_csum_reqd == mpext->csum_reqd) { | |
648ef4b8 | 1020 | skb_ext_del(skb, SKB_EXT_MPTCP); |
dd8bcd17 | 1021 | goto validate_csum; |
648ef4b8 MM |
1022 | } |
1023 | ||
1024 | /* If this skb data are fully covered by the current mapping, | |
1025 | * the new map would need caching, which is not supported | |
1026 | */ | |
fc518953 FW |
1027 | if (skb_is_fully_mapped(ssk, skb)) { |
1028 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSNOMATCH); | |
648ef4b8 | 1029 | return MAPPING_INVALID; |
fc518953 | 1030 | } |
648ef4b8 MM |
1031 | |
1032 | /* will validate the next map after consuming the current one */ | |
dd8bcd17 | 1033 | goto validate_csum; |
648ef4b8 MM |
1034 | } |
1035 | ||
1036 | subflow->map_seq = map_seq; | |
1037 | subflow->map_subflow_seq = mpext->subflow_seq; | |
1038 | subflow->map_data_len = data_len; | |
1039 | subflow->map_valid = 1; | |
dd8bcd17 | 1040 | subflow->map_data_fin = mpext->data_fin; |
d22f4988 | 1041 | subflow->mpc_map = mpext->mpc_map; |
dd8bcd17 PA |
1042 | subflow->map_csum_reqd = mpext->csum_reqd; |
1043 | subflow->map_csum_len = 0; | |
1044 | subflow->map_data_csum = csum_unfold(mpext->csum); | |
1045 | ||
1046 | /* Cfr RFC 8684 Section 3.3.0 */ | |
1047 | if (unlikely(subflow->map_csum_reqd != csum_reqd)) | |
1048 | return MAPPING_INVALID; | |
1049 | ||
1050 | pr_debug("new map seq=%llu subflow_seq=%u data_len=%u csum=%d:%u", | |
648ef4b8 | 1051 | subflow->map_seq, subflow->map_subflow_seq, |
dd8bcd17 PA |
1052 | subflow->map_data_len, subflow->map_csum_reqd, |
1053 | subflow->map_data_csum); | |
648ef4b8 MM |
1054 | |
1055 | validate_seq: | |
1056 | /* we revalidate valid mapping on new skb, because we must ensure | |
1057 | * the current skb is completely covered by the available mapping | |
1058 | */ | |
06285da9 PA |
1059 | if (!validate_mapping(ssk, skb)) { |
1060 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSTCPMISMATCH); | |
648ef4b8 | 1061 | return MAPPING_INVALID; |
06285da9 | 1062 | } |
648ef4b8 MM |
1063 | |
1064 | skb_ext_del(skb, SKB_EXT_MPTCP); | |
dd8bcd17 PA |
1065 | |
1066 | validate_csum: | |
1067 | return validate_data_csum(ssk, skb, csum_reqd); | |
648ef4b8 MM |
1068 | } |
1069 | ||
04e4cd4f | 1070 | static void mptcp_subflow_discard_data(struct sock *ssk, struct sk_buff *skb, |
1d39cd8c | 1071 | u64 limit) |
6719331c PA |
1072 | { |
1073 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
04e4cd4f PA |
1074 | bool fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; |
1075 | u32 incr; | |
1076 | ||
1077 | incr = limit >= skb->len ? skb->len + fin : limit; | |
1078 | ||
1079 | pr_debug("discarding=%d len=%d seq=%d", incr, skb->len, | |
1080 | subflow->map_subflow_seq); | |
06242e44 | 1081 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DUPDATA); |
04e4cd4f PA |
1082 | tcp_sk(ssk)->copied_seq += incr; |
1083 | if (!before(tcp_sk(ssk)->copied_seq, TCP_SKB_CB(skb)->end_seq)) | |
1084 | sk_eat_skb(ssk, skb); | |
1085 | if (mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len) | |
1086 | subflow->map_valid = 0; | |
6719331c PA |
1087 | } |
1088 | ||
40947e13 FW |
1089 | /* sched mptcp worker to remove the subflow if no more data is pending */ |
1090 | static void subflow_sched_work_if_closed(struct mptcp_sock *msk, struct sock *ssk) | |
1091 | { | |
1092 | struct sock *sk = (struct sock *)msk; | |
1093 | ||
1094 | if (likely(ssk->sk_state != TCP_CLOSE)) | |
1095 | return; | |
1096 | ||
1097 | if (skb_queue_empty(&ssk->sk_receive_queue) && | |
1098 | !test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags)) { | |
1099 | sock_hold(sk); | |
1100 | if (!schedule_work(&msk->work)) | |
1101 | sock_put(sk); | |
1102 | } | |
1103 | } | |
1104 | ||
648ef4b8 MM |
1105 | static bool subflow_check_data_avail(struct sock *ssk) |
1106 | { | |
1107 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
1108 | enum mapping_status status; | |
1109 | struct mptcp_sock *msk; | |
1110 | struct sk_buff *skb; | |
1111 | ||
47bebdf3 | 1112 | if (!skb_peek(&ssk->sk_receive_queue)) |
99d1055c | 1113 | WRITE_ONCE(subflow->data_avail, 0); |
648ef4b8 MM |
1114 | if (subflow->data_avail) |
1115 | return true; | |
1116 | ||
648ef4b8 MM |
1117 | msk = mptcp_sk(subflow->conn); |
1118 | for (;;) { | |
648ef4b8 MM |
1119 | u64 ack_seq; |
1120 | u64 old_ack; | |
1121 | ||
43b54c6e | 1122 | status = get_mapping_status(ssk, msk); |
d96a838a | 1123 | trace_subflow_check_data_avail(status, skb_peek(&ssk->sk_receive_queue)); |
dea2b1ea PA |
1124 | if (unlikely(status == MAPPING_INVALID)) |
1125 | goto fallback; | |
1126 | ||
1127 | if (unlikely(status == MAPPING_DUMMY)) | |
1128 | goto fallback; | |
648ef4b8 MM |
1129 | |
1130 | if (status != MAPPING_OK) | |
40947e13 | 1131 | goto no_data; |
648ef4b8 MM |
1132 | |
1133 | skb = skb_peek(&ssk->sk_receive_queue); | |
1134 | if (WARN_ON_ONCE(!skb)) | |
40947e13 | 1135 | goto no_data; |
648ef4b8 | 1136 | |
d22f4988 CP |
1137 | /* if msk lacks the remote key, this subflow must provide an |
1138 | * MP_CAPABLE-based mapping | |
1139 | */ | |
1140 | if (unlikely(!READ_ONCE(msk->can_ack))) { | |
dea2b1ea PA |
1141 | if (!subflow->mpc_map) |
1142 | goto fallback; | |
d22f4988 CP |
1143 | WRITE_ONCE(msk->remote_key, subflow->remote_key); |
1144 | WRITE_ONCE(msk->ack_seq, subflow->map_seq); | |
1145 | WRITE_ONCE(msk->can_ack, true); | |
1146 | } | |
1147 | ||
648ef4b8 MM |
1148 | old_ack = READ_ONCE(msk->ack_seq); |
1149 | ack_seq = mptcp_subflow_get_mapped_dsn(subflow); | |
1150 | pr_debug("msk ack_seq=%llx subflow ack_seq=%llx", old_ack, | |
1151 | ack_seq); | |
99d1055c PA |
1152 | if (unlikely(before64(ack_seq, old_ack))) { |
1153 | mptcp_subflow_discard_data(ssk, skb, old_ack - ack_seq); | |
1154 | continue; | |
47bebdf3 | 1155 | } |
648ef4b8 | 1156 | |
99d1055c PA |
1157 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL); |
1158 | break; | |
648ef4b8 MM |
1159 | } |
1160 | return true; | |
1161 | ||
40947e13 FW |
1162 | no_data: |
1163 | subflow_sched_work_if_closed(msk, ssk); | |
1164 | return false; | |
dea2b1ea PA |
1165 | |
1166 | fallback: | |
1167 | /* RFC 8684 section 3.7. */ | |
478d7700 GT |
1168 | if (subflow->send_mp_fail) { |
1169 | if (mptcp_has_another_subflow(ssk)) { | |
1170 | while ((skb = skb_peek(&ssk->sk_receive_queue))) | |
1171 | sk_eat_skb(ssk, skb); | |
1172 | } | |
1173 | ssk->sk_err = EBADMSG; | |
1174 | tcp_set_state(ssk, TCP_CLOSE); | |
1175 | subflow->reset_transient = 0; | |
1176 | subflow->reset_reason = MPTCP_RST_EMIDDLEBOX; | |
1177 | tcp_send_active_reset(ssk, GFP_ATOMIC); | |
1178 | WRITE_ONCE(subflow->data_avail, 0); | |
1179 | return true; | |
1180 | } | |
1181 | ||
dea2b1ea PA |
1182 | if (subflow->mp_join || subflow->fully_established) { |
1183 | /* fatal protocol error, close the socket. | |
1184 | * subflow_error_report() will introduce the appropriate barriers | |
1185 | */ | |
1186 | ssk->sk_err = EBADMSG; | |
dea2b1ea PA |
1187 | tcp_set_state(ssk, TCP_CLOSE); |
1188 | subflow->reset_transient = 0; | |
1189 | subflow->reset_reason = MPTCP_RST_EMPTCP; | |
1190 | tcp_send_active_reset(ssk, GFP_ATOMIC); | |
99d1055c | 1191 | WRITE_ONCE(subflow->data_avail, 0); |
dea2b1ea PA |
1192 | return false; |
1193 | } | |
1194 | ||
1195 | __mptcp_do_fallback(msk); | |
1196 | skb = skb_peek(&ssk->sk_receive_queue); | |
1197 | subflow->map_valid = 1; | |
1198 | subflow->map_seq = READ_ONCE(msk->ack_seq); | |
1199 | subflow->map_data_len = skb->len; | |
1200 | subflow->map_subflow_seq = tcp_sk(ssk)->copied_seq - subflow->ssn_offset; | |
99d1055c | 1201 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL); |
dea2b1ea | 1202 | return true; |
648ef4b8 MM |
1203 | } |
1204 | ||
1205 | bool mptcp_subflow_data_available(struct sock *sk) | |
1206 | { | |
1207 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
648ef4b8 MM |
1208 | |
1209 | /* check if current mapping is still valid */ | |
1210 | if (subflow->map_valid && | |
1211 | mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len) { | |
1212 | subflow->map_valid = 0; | |
99d1055c | 1213 | WRITE_ONCE(subflow->data_avail, 0); |
648ef4b8 MM |
1214 | |
1215 | pr_debug("Done with mapping: seq=%u data_len=%u", | |
1216 | subflow->map_subflow_seq, | |
1217 | subflow->map_data_len); | |
1218 | } | |
1219 | ||
47bebdf3 | 1220 | return subflow_check_data_avail(sk); |
648ef4b8 MM |
1221 | } |
1222 | ||
071c8ed6 FW |
1223 | /* If ssk has an mptcp parent socket, use the mptcp rcvbuf occupancy, |
1224 | * not the ssk one. | |
1225 | * | |
1226 | * In mptcp, rwin is about the mptcp-level connection data. | |
1227 | * | |
1228 | * Data that is still on the ssk rx queue can thus be ignored, | |
55320b82 | 1229 | * as far as mptcp peer is concerned that data is still inflight. |
071c8ed6 FW |
1230 | * DSS ACK is updated when skb is moved to the mptcp rx queue. |
1231 | */ | |
1232 | void mptcp_space(const struct sock *ssk, int *space, int *full_space) | |
1233 | { | |
1234 | const struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
1235 | const struct sock *sk = subflow->conn; | |
1236 | ||
ea4ca586 | 1237 | *space = __mptcp_space(sk); |
071c8ed6 FW |
1238 | *full_space = tcp_full_space(sk); |
1239 | } | |
1240 | ||
15cc1045 PA |
1241 | void __mptcp_error_report(struct sock *sk) |
1242 | { | |
1243 | struct mptcp_subflow_context *subflow; | |
1244 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1245 | ||
1246 | mptcp_for_each_subflow(msk, subflow) { | |
1247 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
1248 | int err = sock_error(ssk); | |
1249 | ||
1250 | if (!err) | |
1251 | continue; | |
1252 | ||
1253 | /* only propagate errors on fallen-back sockets or | |
1254 | * on MPC connect | |
1255 | */ | |
1256 | if (sk->sk_state != TCP_SYN_SENT && !__mptcp_check_fallback(msk)) | |
1257 | continue; | |
1258 | ||
1259 | inet_sk_state_store(sk, inet_sk_state_load(ssk)); | |
1260 | sk->sk_err = -err; | |
1261 | ||
1262 | /* This barrier is coupled with smp_rmb() in mptcp_poll() */ | |
1263 | smp_wmb(); | |
e3ae2365 | 1264 | sk_error_report(sk); |
15cc1045 PA |
1265 | break; |
1266 | } | |
1267 | } | |
1268 | ||
1269 | static void subflow_error_report(struct sock *ssk) | |
1270 | { | |
1271 | struct sock *sk = mptcp_subflow_ctx(ssk)->conn; | |
1272 | ||
1273 | mptcp_data_lock(sk); | |
1274 | if (!sock_owned_by_user(sk)) | |
1275 | __mptcp_error_report(sk); | |
1276 | else | |
1277 | set_bit(MPTCP_ERROR_REPORT, &mptcp_sk(sk)->flags); | |
1278 | mptcp_data_unlock(sk); | |
1279 | } | |
1280 | ||
499ada50 PA |
1281 | static void subflow_data_ready(struct sock *sk) |
1282 | { | |
1283 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
1284 | u16 state = 1 << inet_sk_state_load(sk); | |
1285 | struct sock *parent = subflow->conn; | |
1286 | struct mptcp_sock *msk; | |
1287 | ||
1288 | msk = mptcp_sk(parent); | |
1289 | if (state & TCPF_LISTEN) { | |
1290 | /* MPJ subflow are removed from accept queue before reaching here, | |
1291 | * avoid stray wakeups | |
1292 | */ | |
1293 | if (reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue)) | |
1294 | return; | |
1295 | ||
1296 | set_bit(MPTCP_DATA_READY, &msk->flags); | |
1297 | parent->sk_data_ready(parent); | |
1298 | return; | |
1299 | } | |
1300 | ||
1301 | WARN_ON_ONCE(!__mptcp_check_fallback(msk) && !subflow->mp_capable && | |
1302 | !subflow->mp_join && !(state & TCPF_CLOSE)); | |
1303 | ||
1304 | if (mptcp_subflow_data_available(sk)) | |
1305 | mptcp_data_ready(parent, sk); | |
1306 | else if (unlikely(sk->sk_err)) | |
1307 | subflow_error_report(sk); | |
1308 | } | |
1309 | ||
1310 | static void subflow_write_space(struct sock *ssk) | |
1311 | { | |
1312 | struct sock *sk = mptcp_subflow_ctx(ssk)->conn; | |
1313 | ||
1314 | mptcp_propagate_sndbuf(sk, ssk); | |
1315 | mptcp_write_space(sk); | |
1316 | } | |
1317 | ||
cec37a6e PK |
1318 | static struct inet_connection_sock_af_ops * |
1319 | subflow_default_af_ops(struct sock *sk) | |
1320 | { | |
1321 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1322 | if (sk->sk_family == AF_INET6) | |
1323 | return &subflow_v6_specific; | |
1324 | #endif | |
1325 | return &subflow_specific; | |
1326 | } | |
1327 | ||
cec37a6e | 1328 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
31484d56 GU |
1329 | void mptcpv6_handle_mapped(struct sock *sk, bool mapped) |
1330 | { | |
cec37a6e PK |
1331 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); |
1332 | struct inet_connection_sock *icsk = inet_csk(sk); | |
1333 | struct inet_connection_sock_af_ops *target; | |
1334 | ||
1335 | target = mapped ? &subflow_v6m_specific : subflow_default_af_ops(sk); | |
1336 | ||
1337 | pr_debug("subflow=%p family=%d ops=%p target=%p mapped=%d", | |
edc7e489 | 1338 | subflow, sk->sk_family, icsk->icsk_af_ops, target, mapped); |
cec37a6e PK |
1339 | |
1340 | if (likely(icsk->icsk_af_ops == target)) | |
1341 | return; | |
1342 | ||
1343 | subflow->icsk_af_ops = icsk->icsk_af_ops; | |
1344 | icsk->icsk_af_ops = target; | |
cec37a6e | 1345 | } |
31484d56 | 1346 | #endif |
cec37a6e | 1347 | |
1729cf18 GT |
1348 | void mptcp_info2sockaddr(const struct mptcp_addr_info *info, |
1349 | struct sockaddr_storage *addr, | |
1350 | unsigned short family) | |
ec3edaa7 PK |
1351 | { |
1352 | memset(addr, 0, sizeof(*addr)); | |
50a13bc3 | 1353 | addr->ss_family = family; |
ec3edaa7 PK |
1354 | if (addr->ss_family == AF_INET) { |
1355 | struct sockaddr_in *in_addr = (struct sockaddr_in *)addr; | |
1356 | ||
50a13bc3 MB |
1357 | if (info->family == AF_INET) |
1358 | in_addr->sin_addr = info->addr; | |
1359 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1360 | else if (ipv6_addr_v4mapped(&info->addr6)) | |
1361 | in_addr->sin_addr.s_addr = info->addr6.s6_addr32[3]; | |
1362 | #endif | |
ec3edaa7 PK |
1363 | in_addr->sin_port = info->port; |
1364 | } | |
1365 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1366 | else if (addr->ss_family == AF_INET6) { | |
1367 | struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)addr; | |
1368 | ||
50a13bc3 MB |
1369 | if (info->family == AF_INET) |
1370 | ipv6_addr_set_v4mapped(info->addr.s_addr, | |
1371 | &in6_addr->sin6_addr); | |
1372 | else | |
1373 | in6_addr->sin6_addr = info->addr6; | |
ec3edaa7 PK |
1374 | in6_addr->sin6_port = info->port; |
1375 | } | |
1376 | #endif | |
1377 | } | |
1378 | ||
ef0da3b8 | 1379 | int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, |
ee285257 | 1380 | const struct mptcp_addr_info *remote) |
ec3edaa7 PK |
1381 | { |
1382 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1383 | struct mptcp_subflow_context *subflow; | |
1384 | struct sockaddr_storage addr; | |
2ff0e566 | 1385 | int remote_id = remote->id; |
6bad912b | 1386 | int local_id = loc->id; |
ec3edaa7 | 1387 | struct socket *sf; |
6bad912b | 1388 | struct sock *ssk; |
ec3edaa7 PK |
1389 | u32 remote_token; |
1390 | int addrlen; | |
ee285257 GT |
1391 | int ifindex; |
1392 | u8 flags; | |
ec3edaa7 PK |
1393 | int err; |
1394 | ||
b93df08c | 1395 | if (!mptcp_is_fully_established(sk)) |
ec3edaa7 PK |
1396 | return -ENOTCONN; |
1397 | ||
1398 | err = mptcp_subflow_create_socket(sk, &sf); | |
1399 | if (err) | |
1400 | return err; | |
1401 | ||
6bad912b PA |
1402 | ssk = sf->sk; |
1403 | subflow = mptcp_subflow_ctx(ssk); | |
1404 | do { | |
1405 | get_random_bytes(&subflow->local_nonce, sizeof(u32)); | |
1406 | } while (!subflow->local_nonce); | |
1407 | ||
1408 | if (!local_id) { | |
1409 | err = mptcp_pm_get_local_id(msk, (struct sock_common *)ssk); | |
1410 | if (err < 0) | |
1411 | goto failed; | |
1412 | ||
1413 | local_id = err; | |
1414 | } | |
1415 | ||
ee285257 GT |
1416 | mptcp_pm_get_flags_and_ifindex_by_id(sock_net(sk), local_id, |
1417 | &flags, &ifindex); | |
ec3edaa7 PK |
1418 | subflow->remote_key = msk->remote_key; |
1419 | subflow->local_key = msk->local_key; | |
1420 | subflow->token = msk->token; | |
50a13bc3 | 1421 | mptcp_info2sockaddr(loc, &addr, ssk->sk_family); |
ec3edaa7 PK |
1422 | |
1423 | addrlen = sizeof(struct sockaddr_in); | |
1424 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
50a13bc3 | 1425 | if (addr.ss_family == AF_INET6) |
ec3edaa7 PK |
1426 | addrlen = sizeof(struct sockaddr_in6); |
1427 | #endif | |
c9406a23 FW |
1428 | mptcp_sockopt_sync(msk, ssk); |
1429 | ||
daa83ab0 | 1430 | ssk->sk_bound_dev_if = ifindex; |
ec3edaa7 PK |
1431 | err = kernel_bind(sf, (struct sockaddr *)&addr, addrlen); |
1432 | if (err) | |
1433 | goto failed; | |
1434 | ||
1435 | mptcp_crypto_key_sha(subflow->remote_key, &remote_token, NULL); | |
2ff0e566 GT |
1436 | pr_debug("msk=%p remote_token=%u local_id=%d remote_id=%d", msk, |
1437 | remote_token, local_id, remote_id); | |
ec3edaa7 | 1438 | subflow->remote_token = remote_token; |
6bad912b | 1439 | subflow->local_id = local_id; |
2ff0e566 | 1440 | subflow->remote_id = remote_id; |
ec3edaa7 | 1441 | subflow->request_join = 1; |
daa83ab0 | 1442 | subflow->request_bkup = !!(flags & MPTCP_PM_ADDR_FLAG_BACKUP); |
50a13bc3 | 1443 | mptcp_info2sockaddr(remote, &addr, ssk->sk_family); |
ec3edaa7 | 1444 | |
5b950ff4 | 1445 | mptcp_add_pending_subflow(msk, subflow); |
ec3edaa7 PK |
1446 | err = kernel_connect(sf, (struct sockaddr *)&addr, addrlen, O_NONBLOCK); |
1447 | if (err && err != -EINPROGRESS) | |
5b950ff4 | 1448 | goto failed_unlink; |
ec3edaa7 | 1449 | |
866f26f2 PA |
1450 | /* discard the subflow socket */ |
1451 | mptcp_sock_graft(ssk, sk->sk_socket); | |
1452 | iput(SOCK_INODE(sf)); | |
ec3edaa7 PK |
1453 | return err; |
1454 | ||
5b950ff4 | 1455 | failed_unlink: |
ec3edaa7 | 1456 | spin_lock_bh(&msk->join_list_lock); |
5b950ff4 | 1457 | list_del(&subflow->node); |
ec3edaa7 | 1458 | spin_unlock_bh(&msk->join_list_lock); |
f0715779 | 1459 | sock_put(mptcp_subflow_tcp_sock(subflow)); |
ec3edaa7 | 1460 | |
ec3edaa7 | 1461 | failed: |
e16163b6 | 1462 | subflow->disposable = 1; |
ec3edaa7 PK |
1463 | sock_release(sf); |
1464 | return err; | |
1465 | } | |
1466 | ||
3764b0c5 NR |
1467 | static void mptcp_attach_cgroup(struct sock *parent, struct sock *child) |
1468 | { | |
1469 | #ifdef CONFIG_SOCK_CGROUP_DATA | |
1470 | struct sock_cgroup_data *parent_skcd = &parent->sk_cgrp_data, | |
1471 | *child_skcd = &child->sk_cgrp_data; | |
1472 | ||
1473 | /* only the additional subflows created by kworkers have to be modified */ | |
1474 | if (cgroup_id(sock_cgroup_ptr(parent_skcd)) != | |
1475 | cgroup_id(sock_cgroup_ptr(child_skcd))) { | |
1476 | #ifdef CONFIG_MEMCG | |
1477 | struct mem_cgroup *memcg = parent->sk_memcg; | |
1478 | ||
1479 | mem_cgroup_sk_free(child); | |
1480 | if (memcg && css_tryget(&memcg->css)) | |
1481 | child->sk_memcg = memcg; | |
1482 | #endif /* CONFIG_MEMCG */ | |
1483 | ||
1484 | cgroup_sk_free(child_skcd); | |
1485 | *child_skcd = *parent_skcd; | |
1486 | cgroup_sk_clone(child_skcd); | |
1487 | } | |
1488 | #endif /* CONFIG_SOCK_CGROUP_DATA */ | |
1489 | } | |
1490 | ||
b19bc294 PA |
1491 | static void mptcp_subflow_ops_override(struct sock *ssk) |
1492 | { | |
1493 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1494 | if (ssk->sk_prot == &tcpv6_prot) | |
1495 | ssk->sk_prot = &tcpv6_prot_override; | |
1496 | else | |
1497 | #endif | |
1498 | ssk->sk_prot = &tcp_prot_override; | |
1499 | } | |
1500 | ||
1501 | static void mptcp_subflow_ops_undo_override(struct sock *ssk) | |
1502 | { | |
1503 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1504 | if (ssk->sk_prot == &tcpv6_prot_override) | |
1505 | ssk->sk_prot = &tcpv6_prot; | |
1506 | else | |
1507 | #endif | |
1508 | ssk->sk_prot = &tcp_prot; | |
1509 | } | |
2303f994 PK |
1510 | int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock) |
1511 | { | |
1512 | struct mptcp_subflow_context *subflow; | |
1513 | struct net *net = sock_net(sk); | |
1514 | struct socket *sf; | |
1515 | int err; | |
1516 | ||
adf73410 PA |
1517 | /* un-accepted server sockets can reach here - on bad configuration |
1518 | * bail early to avoid greater trouble later | |
1519 | */ | |
1520 | if (unlikely(!sk->sk_socket)) | |
1521 | return -EINVAL; | |
1522 | ||
cec37a6e PK |
1523 | err = sock_create_kern(net, sk->sk_family, SOCK_STREAM, IPPROTO_TCP, |
1524 | &sf); | |
2303f994 PK |
1525 | if (err) |
1526 | return err; | |
1527 | ||
1528 | lock_sock(sf->sk); | |
1529 | ||
3764b0c5 NR |
1530 | /* the newly created socket has to be in the same cgroup as its parent */ |
1531 | mptcp_attach_cgroup(sk, sf->sk); | |
1532 | ||
2303f994 PK |
1533 | /* kernel sockets do not by default acquire net ref, but TCP timer |
1534 | * needs it. | |
1535 | */ | |
1536 | sf->sk->sk_net_refcnt = 1; | |
1537 | get_net(net); | |
d477eb90 | 1538 | sock_inuse_add(net, 1); |
2303f994 PK |
1539 | err = tcp_set_ulp(sf->sk, "mptcp"); |
1540 | release_sock(sf->sk); | |
1541 | ||
b8ad540d WY |
1542 | if (err) { |
1543 | sock_release(sf); | |
2303f994 | 1544 | return err; |
b8ad540d | 1545 | } |
2303f994 | 1546 | |
7d14b0d2 PA |
1547 | /* the newly created socket really belongs to the owning MPTCP master |
1548 | * socket, even if for additional subflows the allocation is performed | |
1549 | * by a kernel workqueue. Adjust inode references, so that the | |
1550 | * procfs/diag interaces really show this one belonging to the correct | |
1551 | * user. | |
1552 | */ | |
1553 | SOCK_INODE(sf)->i_ino = SOCK_INODE(sk->sk_socket)->i_ino; | |
1554 | SOCK_INODE(sf)->i_uid = SOCK_INODE(sk->sk_socket)->i_uid; | |
1555 | SOCK_INODE(sf)->i_gid = SOCK_INODE(sk->sk_socket)->i_gid; | |
1556 | ||
2303f994 PK |
1557 | subflow = mptcp_subflow_ctx(sf->sk); |
1558 | pr_debug("subflow=%p", subflow); | |
1559 | ||
1560 | *new_sock = sf; | |
79c0949e | 1561 | sock_hold(sk); |
2303f994 | 1562 | subflow->conn = sk; |
b19bc294 | 1563 | mptcp_subflow_ops_override(sf->sk); |
2303f994 PK |
1564 | |
1565 | return 0; | |
1566 | } | |
1567 | ||
1568 | static struct mptcp_subflow_context *subflow_create_ctx(struct sock *sk, | |
1569 | gfp_t priority) | |
1570 | { | |
1571 | struct inet_connection_sock *icsk = inet_csk(sk); | |
1572 | struct mptcp_subflow_context *ctx; | |
1573 | ||
1574 | ctx = kzalloc(sizeof(*ctx), priority); | |
1575 | if (!ctx) | |
1576 | return NULL; | |
1577 | ||
1578 | rcu_assign_pointer(icsk->icsk_ulp_data, ctx); | |
cec37a6e | 1579 | INIT_LIST_HEAD(&ctx->node); |
b19bc294 | 1580 | INIT_LIST_HEAD(&ctx->delegated_node); |
2303f994 PK |
1581 | |
1582 | pr_debug("subflow=%p", ctx); | |
1583 | ||
1584 | ctx->tcp_sock = sk; | |
1585 | ||
1586 | return ctx; | |
1587 | } | |
1588 | ||
648ef4b8 MM |
1589 | static void __subflow_state_change(struct sock *sk) |
1590 | { | |
1591 | struct socket_wq *wq; | |
1592 | ||
1593 | rcu_read_lock(); | |
1594 | wq = rcu_dereference(sk->sk_wq); | |
1595 | if (skwq_has_sleeper(wq)) | |
1596 | wake_up_interruptible_all(&wq->wait); | |
1597 | rcu_read_unlock(); | |
1598 | } | |
1599 | ||
1600 | static bool subflow_is_done(const struct sock *sk) | |
1601 | { | |
1602 | return sk->sk_shutdown & RCV_SHUTDOWN || sk->sk_state == TCP_CLOSE; | |
1603 | } | |
1604 | ||
1605 | static void subflow_state_change(struct sock *sk) | |
1606 | { | |
1607 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
dc093db5 | 1608 | struct sock *parent = subflow->conn; |
648ef4b8 MM |
1609 | |
1610 | __subflow_state_change(sk); | |
1611 | ||
8fd73804 | 1612 | if (subflow_simultaneous_connect(sk)) { |
5cf92bba | 1613 | mptcp_propagate_sndbuf(parent, sk); |
8fd73804 | 1614 | mptcp_do_fallback(sk); |
a6b118fe | 1615 | mptcp_rcv_space_init(mptcp_sk(parent), sk); |
8fd73804 DC |
1616 | pr_fallback(mptcp_sk(parent)); |
1617 | subflow->conn_finished = 1; | |
490274b4 | 1618 | mptcp_set_connected(parent); |
8fd73804 DC |
1619 | } |
1620 | ||
648ef4b8 MM |
1621 | /* as recvmsg() does not acquire the subflow socket for ssk selection |
1622 | * a fin packet carrying a DSS can be unnoticed if we don't trigger | |
1623 | * the data available machinery here. | |
1624 | */ | |
e1ff9e82 | 1625 | if (mptcp_subflow_data_available(sk)) |
2e52213c | 1626 | mptcp_data_ready(parent, sk); |
499ada50 PA |
1627 | else if (unlikely(sk->sk_err)) |
1628 | subflow_error_report(sk); | |
648ef4b8 | 1629 | |
40947e13 FW |
1630 | subflow_sched_work_if_closed(mptcp_sk(parent), sk); |
1631 | ||
067a0b3d | 1632 | if (__mptcp_check_fallback(mptcp_sk(parent)) && |
648ef4b8 MM |
1633 | !subflow->rx_eof && subflow_is_done(sk)) { |
1634 | subflow->rx_eof = 1; | |
59832e24 | 1635 | mptcp_subflow_eof(parent); |
648ef4b8 MM |
1636 | } |
1637 | } | |
1638 | ||
2303f994 PK |
1639 | static int subflow_ulp_init(struct sock *sk) |
1640 | { | |
cec37a6e | 1641 | struct inet_connection_sock *icsk = inet_csk(sk); |
2303f994 PK |
1642 | struct mptcp_subflow_context *ctx; |
1643 | struct tcp_sock *tp = tcp_sk(sk); | |
1644 | int err = 0; | |
1645 | ||
1646 | /* disallow attaching ULP to a socket unless it has been | |
1647 | * created with sock_create_kern() | |
1648 | */ | |
1649 | if (!sk->sk_kern_sock) { | |
1650 | err = -EOPNOTSUPP; | |
1651 | goto out; | |
1652 | } | |
1653 | ||
1654 | ctx = subflow_create_ctx(sk, GFP_KERNEL); | |
1655 | if (!ctx) { | |
1656 | err = -ENOMEM; | |
1657 | goto out; | |
1658 | } | |
1659 | ||
1660 | pr_debug("subflow=%p, family=%d", ctx, sk->sk_family); | |
1661 | ||
1662 | tp->is_mptcp = 1; | |
cec37a6e PK |
1663 | ctx->icsk_af_ops = icsk->icsk_af_ops; |
1664 | icsk->icsk_af_ops = subflow_default_af_ops(sk); | |
648ef4b8 MM |
1665 | ctx->tcp_data_ready = sk->sk_data_ready; |
1666 | ctx->tcp_state_change = sk->sk_state_change; | |
1667 | ctx->tcp_write_space = sk->sk_write_space; | |
15cc1045 | 1668 | ctx->tcp_error_report = sk->sk_error_report; |
648ef4b8 MM |
1669 | sk->sk_data_ready = subflow_data_ready; |
1670 | sk->sk_write_space = subflow_write_space; | |
1671 | sk->sk_state_change = subflow_state_change; | |
15cc1045 | 1672 | sk->sk_error_report = subflow_error_report; |
2303f994 PK |
1673 | out: |
1674 | return err; | |
1675 | } | |
1676 | ||
e16163b6 | 1677 | static void subflow_ulp_release(struct sock *ssk) |
2303f994 | 1678 | { |
e16163b6 PA |
1679 | struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(ssk); |
1680 | bool release = true; | |
1681 | struct sock *sk; | |
2303f994 PK |
1682 | |
1683 | if (!ctx) | |
1684 | return; | |
1685 | ||
e16163b6 PA |
1686 | sk = ctx->conn; |
1687 | if (sk) { | |
1688 | /* if the msk has been orphaned, keep the ctx | |
0597d0f8 PA |
1689 | * alive, will be freed by __mptcp_close_ssk(), |
1690 | * when the subflow is still unaccepted | |
e16163b6 | 1691 | */ |
0597d0f8 | 1692 | release = ctx->disposable || list_empty(&ctx->node); |
e16163b6 PA |
1693 | sock_put(sk); |
1694 | } | |
79c0949e | 1695 | |
b19bc294 | 1696 | mptcp_subflow_ops_undo_override(ssk); |
e16163b6 PA |
1697 | if (release) |
1698 | kfree_rcu(ctx, rcu); | |
2303f994 PK |
1699 | } |
1700 | ||
cec37a6e PK |
1701 | static void subflow_ulp_clone(const struct request_sock *req, |
1702 | struct sock *newsk, | |
1703 | const gfp_t priority) | |
1704 | { | |
1705 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); | |
1706 | struct mptcp_subflow_context *old_ctx = mptcp_subflow_ctx(newsk); | |
1707 | struct mptcp_subflow_context *new_ctx; | |
1708 | ||
f296234c PK |
1709 | if (!tcp_rsk(req)->is_mptcp || |
1710 | (!subflow_req->mp_capable && !subflow_req->mp_join)) { | |
648ef4b8 | 1711 | subflow_ulp_fallback(newsk, old_ctx); |
cec37a6e PK |
1712 | return; |
1713 | } | |
1714 | ||
1715 | new_ctx = subflow_create_ctx(newsk, priority); | |
edc7e489 | 1716 | if (!new_ctx) { |
648ef4b8 | 1717 | subflow_ulp_fallback(newsk, old_ctx); |
cec37a6e PK |
1718 | return; |
1719 | } | |
1720 | ||
1721 | new_ctx->conn_finished = 1; | |
1722 | new_ctx->icsk_af_ops = old_ctx->icsk_af_ops; | |
648ef4b8 MM |
1723 | new_ctx->tcp_data_ready = old_ctx->tcp_data_ready; |
1724 | new_ctx->tcp_state_change = old_ctx->tcp_state_change; | |
1725 | new_ctx->tcp_write_space = old_ctx->tcp_write_space; | |
15cc1045 | 1726 | new_ctx->tcp_error_report = old_ctx->tcp_error_report; |
58b09919 PA |
1727 | new_ctx->rel_write_seq = 1; |
1728 | new_ctx->tcp_sock = newsk; | |
1729 | ||
f296234c PK |
1730 | if (subflow_req->mp_capable) { |
1731 | /* see comments in subflow_syn_recv_sock(), MPTCP connection | |
1732 | * is fully established only after we receive the remote key | |
1733 | */ | |
1734 | new_ctx->mp_capable = 1; | |
f296234c PK |
1735 | new_ctx->local_key = subflow_req->local_key; |
1736 | new_ctx->token = subflow_req->token; | |
1737 | new_ctx->ssn_offset = subflow_req->ssn_offset; | |
1738 | new_ctx->idsn = subflow_req->idsn; | |
1739 | } else if (subflow_req->mp_join) { | |
ec3edaa7 | 1740 | new_ctx->ssn_offset = subflow_req->ssn_offset; |
f296234c PK |
1741 | new_ctx->mp_join = 1; |
1742 | new_ctx->fully_established = 1; | |
1743 | new_ctx->backup = subflow_req->backup; | |
1744 | new_ctx->local_id = subflow_req->local_id; | |
2ff0e566 | 1745 | new_ctx->remote_id = subflow_req->remote_id; |
f296234c PK |
1746 | new_ctx->token = subflow_req->token; |
1747 | new_ctx->thmac = subflow_req->thmac; | |
1748 | } | |
cec37a6e PK |
1749 | } |
1750 | ||
b19bc294 PA |
1751 | static void tcp_release_cb_override(struct sock *ssk) |
1752 | { | |
1753 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
1754 | ||
1755 | if (mptcp_subflow_has_delegated_action(subflow)) | |
1756 | mptcp_subflow_process_delegated(ssk); | |
1757 | ||
1758 | tcp_release_cb(ssk); | |
1759 | } | |
1760 | ||
2303f994 PK |
1761 | static struct tcp_ulp_ops subflow_ulp_ops __read_mostly = { |
1762 | .name = "mptcp", | |
1763 | .owner = THIS_MODULE, | |
1764 | .init = subflow_ulp_init, | |
1765 | .release = subflow_ulp_release, | |
cec37a6e | 1766 | .clone = subflow_ulp_clone, |
2303f994 PK |
1767 | }; |
1768 | ||
cec37a6e PK |
1769 | static int subflow_ops_init(struct request_sock_ops *subflow_ops) |
1770 | { | |
1771 | subflow_ops->obj_size = sizeof(struct mptcp_subflow_request_sock); | |
1772 | subflow_ops->slab_name = "request_sock_subflow"; | |
1773 | ||
1774 | subflow_ops->slab = kmem_cache_create(subflow_ops->slab_name, | |
1775 | subflow_ops->obj_size, 0, | |
1776 | SLAB_ACCOUNT | | |
1777 | SLAB_TYPESAFE_BY_RCU, | |
1778 | NULL); | |
1779 | if (!subflow_ops->slab) | |
1780 | return -ENOMEM; | |
1781 | ||
79c0949e PK |
1782 | subflow_ops->destructor = subflow_req_destructor; |
1783 | ||
cec37a6e PK |
1784 | return 0; |
1785 | } | |
1786 | ||
d39dceca | 1787 | void __init mptcp_subflow_init(void) |
2303f994 | 1788 | { |
08b8d080 FW |
1789 | mptcp_subflow_request_sock_ops = tcp_request_sock_ops; |
1790 | if (subflow_ops_init(&mptcp_subflow_request_sock_ops) != 0) | |
cec37a6e PK |
1791 | panic("MPTCP: failed to init subflow request sock ops\n"); |
1792 | ||
1793 | subflow_request_sock_ipv4_ops = tcp_request_sock_ipv4_ops; | |
7ea851d1 | 1794 | subflow_request_sock_ipv4_ops.route_req = subflow_v4_route_req; |
cec37a6e PK |
1795 | |
1796 | subflow_specific = ipv4_specific; | |
1797 | subflow_specific.conn_request = subflow_v4_conn_request; | |
1798 | subflow_specific.syn_recv_sock = subflow_syn_recv_sock; | |
1799 | subflow_specific.sk_rx_dst_set = subflow_finish_connect; | |
1800 | ||
b19bc294 PA |
1801 | tcp_prot_override = tcp_prot; |
1802 | tcp_prot_override.release_cb = tcp_release_cb_override; | |
1803 | ||
cec37a6e PK |
1804 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
1805 | subflow_request_sock_ipv6_ops = tcp_request_sock_ipv6_ops; | |
7ea851d1 | 1806 | subflow_request_sock_ipv6_ops.route_req = subflow_v6_route_req; |
cec37a6e PK |
1807 | |
1808 | subflow_v6_specific = ipv6_specific; | |
1809 | subflow_v6_specific.conn_request = subflow_v6_conn_request; | |
1810 | subflow_v6_specific.syn_recv_sock = subflow_syn_recv_sock; | |
1811 | subflow_v6_specific.sk_rx_dst_set = subflow_finish_connect; | |
1812 | ||
1813 | subflow_v6m_specific = subflow_v6_specific; | |
1814 | subflow_v6m_specific.queue_xmit = ipv4_specific.queue_xmit; | |
1815 | subflow_v6m_specific.send_check = ipv4_specific.send_check; | |
1816 | subflow_v6m_specific.net_header_len = ipv4_specific.net_header_len; | |
1817 | subflow_v6m_specific.mtu_reduced = ipv4_specific.mtu_reduced; | |
1818 | subflow_v6m_specific.net_frag_header_len = 0; | |
b19bc294 PA |
1819 | |
1820 | tcpv6_prot_override = tcpv6_prot; | |
1821 | tcpv6_prot_override.release_cb = tcp_release_cb_override; | |
cec37a6e PK |
1822 | #endif |
1823 | ||
5147dfb5 DC |
1824 | mptcp_diag_subflow_init(&subflow_ulp_ops); |
1825 | ||
2303f994 PK |
1826 | if (tcp_register_ulp(&subflow_ulp_ops) != 0) |
1827 | panic("MPTCP: failed to register subflows to ULP\n"); | |
1828 | } |