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 | |
0799e21b | 156 | mptcp_get_options(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); |
0799e21b | 253 | mptcp_get_options(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", | |
742e2f36 | 347 | subflow, subflow->token, thmac, subflow->thmac); |
ec3edaa7 PK |
348 | |
349 | return thmac == subflow->thmac; | |
350 | } | |
351 | ||
d5824847 PA |
352 | void mptcp_subflow_reset(struct sock *ssk) |
353 | { | |
0e4f35d7 PA |
354 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); |
355 | struct sock *sk = subflow->conn; | |
356 | ||
ab82e996 FW |
357 | /* must hold: tcp_done() could drop last reference on parent */ |
358 | sock_hold(sk); | |
359 | ||
d5824847 PA |
360 | tcp_set_state(ssk, TCP_CLOSE); |
361 | tcp_send_active_reset(ssk, GFP_ATOMIC); | |
362 | tcp_done(ssk); | |
0e4f35d7 PA |
363 | if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags) && |
364 | schedule_work(&mptcp_sk(sk)->work)) | |
ab82e996 FW |
365 | return; /* worker will put sk for us */ |
366 | ||
367 | sock_put(sk); | |
d5824847 PA |
368 | } |
369 | ||
5bc56388 GT |
370 | static bool subflow_use_different_dport(struct mptcp_sock *msk, const struct sock *sk) |
371 | { | |
372 | return inet_sk(sk)->inet_dport != inet_sk((struct sock *)msk)->inet_dport; | |
373 | } | |
374 | ||
490274b4 PA |
375 | void __mptcp_set_connected(struct sock *sk) |
376 | { | |
377 | if (sk->sk_state == TCP_SYN_SENT) { | |
378 | inet_sk_state_store(sk, TCP_ESTABLISHED); | |
379 | sk->sk_state_change(sk); | |
380 | } | |
381 | } | |
382 | ||
383 | static void mptcp_set_connected(struct sock *sk) | |
384 | { | |
385 | mptcp_data_lock(sk); | |
386 | if (!sock_owned_by_user(sk)) | |
387 | __mptcp_set_connected(sk); | |
388 | else | |
e9d09bac | 389 | __set_bit(MPTCP_CONNECTED, &mptcp_sk(sk)->cb_flags); |
490274b4 PA |
390 | mptcp_data_unlock(sk); |
391 | } | |
392 | ||
cec37a6e PK |
393 | static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb) |
394 | { | |
395 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
cfde141e | 396 | struct mptcp_options_received mp_opt; |
c3c123d1 | 397 | struct sock *parent = subflow->conn; |
cec37a6e PK |
398 | |
399 | subflow->icsk_af_ops->sk_rx_dst_set(sk, skb); | |
400 | ||
263e1201 PA |
401 | /* be sure no special action on any packet other than syn-ack */ |
402 | if (subflow->conn_finished) | |
403 | return; | |
404 | ||
5cf92bba | 405 | mptcp_propagate_sndbuf(parent, sk); |
b0977bb2 | 406 | subflow->rel_write_seq = 1; |
263e1201 | 407 | subflow->conn_finished = 1; |
e1ff9e82 DC |
408 | subflow->ssn_offset = TCP_SKB_CB(skb)->seq; |
409 | pr_debug("subflow=%p synack seq=%x", subflow, subflow->ssn_offset); | |
263e1201 | 410 | |
0799e21b | 411 | mptcp_get_options(skb, &mp_opt); |
fa25e815 | 412 | if (subflow->request_mptcp) { |
74c7dfbe | 413 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) { |
fa25e815 PA |
414 | MPTCP_INC_STATS(sock_net(sk), |
415 | MPTCP_MIB_MPCAPABLEACTIVEFALLBACK); | |
416 | mptcp_do_fallback(sk); | |
417 | pr_fallback(mptcp_sk(subflow->conn)); | |
418 | goto fallback; | |
419 | } | |
420 | ||
74c7dfbe | 421 | if (mp_opt.suboptions & OPTION_MPTCP_CSUMREQD) |
06251181 | 422 | WRITE_ONCE(mptcp_sk(parent)->csum_enabled, true); |
df377be3 GT |
423 | if (mp_opt.deny_join_id0) |
424 | WRITE_ONCE(mptcp_sk(parent)->pm.remote_deny_join_id0, true); | |
263e1201 PA |
425 | subflow->mp_capable = 1; |
426 | subflow->can_ack = 1; | |
cfde141e | 427 | subflow->remote_key = mp_opt.sndr_key; |
263e1201 PA |
428 | pr_debug("subflow=%p, remote_key=%llu", subflow, |
429 | subflow->remote_key); | |
5695eb88 | 430 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVEACK); |
fa25e815 | 431 | mptcp_finish_connect(sk); |
490274b4 | 432 | mptcp_set_connected(parent); |
fa25e815 PA |
433 | } else if (subflow->request_join) { |
434 | u8 hmac[SHA256_DIGEST_SIZE]; | |
435 | ||
74c7dfbe | 436 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ)) { |
dc87efdb | 437 | subflow->reset_reason = MPTCP_RST_EMPTCP; |
fa25e815 | 438 | goto do_reset; |
dc87efdb | 439 | } |
fa25e815 | 440 | |
0460ce22 | 441 | subflow->backup = mp_opt.backup; |
cfde141e PA |
442 | subflow->thmac = mp_opt.thmac; |
443 | subflow->remote_nonce = mp_opt.nonce; | |
0460ce22 PA |
444 | pr_debug("subflow=%p, thmac=%llu, remote_nonce=%u backup=%d", |
445 | subflow, subflow->thmac, subflow->remote_nonce, | |
446 | subflow->backup); | |
263e1201 | 447 | |
ec3edaa7 | 448 | if (!subflow_thmac_valid(subflow)) { |
fc518953 | 449 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINACKMAC); |
dc87efdb | 450 | subflow->reset_reason = MPTCP_RST_EMPTCP; |
ec3edaa7 PK |
451 | goto do_reset; |
452 | } | |
453 | ||
0a4d8e96 JW |
454 | if (!mptcp_finish_join(sk)) |
455 | goto do_reset; | |
456 | ||
ec3edaa7 PK |
457 | subflow_generate_hmac(subflow->local_key, subflow->remote_key, |
458 | subflow->local_nonce, | |
459 | subflow->remote_nonce, | |
bd697222 | 460 | hmac); |
bd697222 | 461 | memcpy(subflow->hmac, hmac, MPTCPOPT_HMAC_LEN); |
ec3edaa7 | 462 | |
fa25e815 | 463 | subflow->mp_join = 1; |
fc518953 | 464 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX); |
5bc56388 GT |
465 | |
466 | if (subflow_use_different_dport(mptcp_sk(parent), sk)) { | |
467 | pr_debug("synack inet_dport=%d %d", | |
468 | ntohs(inet_sk(sk)->inet_dport), | |
469 | ntohs(inet_sk(parent)->inet_dport)); | |
2fbdd9ea | 470 | MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINPORTSYNACKRX); |
5bc56388 | 471 | } |
fa25e815 PA |
472 | } else if (mptcp_check_fallback(sk)) { |
473 | fallback: | |
474 | mptcp_rcv_space_init(mptcp_sk(parent), sk); | |
490274b4 | 475 | mptcp_set_connected(parent); |
cec37a6e | 476 | } |
fa25e815 PA |
477 | return; |
478 | ||
479 | do_reset: | |
dc87efdb | 480 | subflow->reset_transient = 0; |
d5824847 | 481 | mptcp_subflow_reset(sk); |
cec37a6e PK |
482 | } |
483 | ||
4cf86ae8 PA |
484 | static void subflow_set_local_id(struct mptcp_subflow_context *subflow, int local_id) |
485 | { | |
486 | subflow->local_id = local_id; | |
487 | subflow->local_id_valid = 1; | |
488 | } | |
489 | ||
490 | static int subflow_chk_local_id(struct sock *sk) | |
491 | { | |
492 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
493 | struct mptcp_sock *msk = mptcp_sk(subflow->conn); | |
494 | int err; | |
495 | ||
496 | if (likely(subflow->local_id_valid)) | |
497 | return 0; | |
498 | ||
499 | err = mptcp_pm_get_local_id(msk, (struct sock_common *)sk); | |
500 | if (err < 0) | |
501 | return err; | |
502 | ||
503 | subflow_set_local_id(subflow, err); | |
504 | return 0; | |
505 | } | |
506 | ||
507 | static int subflow_rebuild_header(struct sock *sk) | |
508 | { | |
509 | int err = subflow_chk_local_id(sk); | |
510 | ||
511 | if (unlikely(err < 0)) | |
512 | return err; | |
513 | ||
514 | return inet_sk_rebuild_header(sk); | |
515 | } | |
516 | ||
517 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
518 | static int subflow_v6_rebuild_header(struct sock *sk) | |
519 | { | |
520 | int err = subflow_chk_local_id(sk); | |
521 | ||
522 | if (unlikely(err < 0)) | |
523 | return err; | |
524 | ||
525 | return inet6_sk_rebuild_header(sk); | |
526 | } | |
527 | #endif | |
528 | ||
08b8d080 | 529 | struct request_sock_ops mptcp_subflow_request_sock_ops; |
51fa7f8e | 530 | static struct tcp_request_sock_ops subflow_request_sock_ipv4_ops __ro_after_init; |
cec37a6e PK |
531 | |
532 | static int subflow_v4_conn_request(struct sock *sk, struct sk_buff *skb) | |
533 | { | |
534 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
535 | ||
536 | pr_debug("subflow=%p", subflow); | |
537 | ||
538 | /* Never answer to SYNs sent to broadcast or multicast */ | |
539 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) | |
540 | goto drop; | |
541 | ||
08b8d080 | 542 | return tcp_conn_request(&mptcp_subflow_request_sock_ops, |
cec37a6e PK |
543 | &subflow_request_sock_ipv4_ops, |
544 | sk, skb); | |
545 | drop: | |
546 | tcp_listendrop(sk); | |
547 | return 0; | |
548 | } | |
549 | ||
550 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
51fa7f8e FW |
551 | static struct tcp_request_sock_ops subflow_request_sock_ipv6_ops __ro_after_init; |
552 | static struct inet_connection_sock_af_ops subflow_v6_specific __ro_after_init; | |
553 | static struct inet_connection_sock_af_ops subflow_v6m_specific __ro_after_init; | |
b19bc294 | 554 | static struct proto tcpv6_prot_override; |
cec37a6e PK |
555 | |
556 | static int subflow_v6_conn_request(struct sock *sk, struct sk_buff *skb) | |
557 | { | |
558 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
559 | ||
560 | pr_debug("subflow=%p", subflow); | |
561 | ||
562 | if (skb->protocol == htons(ETH_P_IP)) | |
563 | return subflow_v4_conn_request(sk, skb); | |
564 | ||
565 | if (!ipv6_unicast_destination(skb)) | |
566 | goto drop; | |
567 | ||
dcc32f4f JK |
568 | if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) { |
569 | __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS); | |
570 | return 0; | |
571 | } | |
572 | ||
08b8d080 | 573 | return tcp_conn_request(&mptcp_subflow_request_sock_ops, |
cec37a6e PK |
574 | &subflow_request_sock_ipv6_ops, sk, skb); |
575 | ||
576 | drop: | |
577 | tcp_listendrop(sk); | |
578 | return 0; /* don't send reset */ | |
579 | } | |
580 | #endif | |
581 | ||
f296234c PK |
582 | /* validate hmac received in third ACK */ |
583 | static bool subflow_hmac_valid(const struct request_sock *req, | |
cfde141e | 584 | const struct mptcp_options_received *mp_opt) |
f296234c PK |
585 | { |
586 | const struct mptcp_subflow_request_sock *subflow_req; | |
bd697222 | 587 | u8 hmac[SHA256_DIGEST_SIZE]; |
f296234c | 588 | struct mptcp_sock *msk; |
f296234c PK |
589 | |
590 | subflow_req = mptcp_subflow_rsk(req); | |
8fd4de12 | 591 | msk = subflow_req->msk; |
f296234c PK |
592 | if (!msk) |
593 | return false; | |
594 | ||
595 | subflow_generate_hmac(msk->remote_key, msk->local_key, | |
596 | subflow_req->remote_nonce, | |
597 | subflow_req->local_nonce, hmac); | |
598 | ||
8fd4de12 | 599 | return !crypto_memneq(hmac, mp_opt->hmac, MPTCPOPT_HMAC_LEN); |
f296234c PK |
600 | } |
601 | ||
df1036da FW |
602 | static void mptcp_sock_destruct(struct sock *sk) |
603 | { | |
604 | /* if new mptcp socket isn't accepted, it is free'd | |
605 | * from the tcp listener sockets request queue, linked | |
606 | * from req->sk. The tcp socket is released. | |
607 | * This calls the ULP release function which will | |
608 | * also remove the mptcp socket, via | |
609 | * sock_put(ctx->conn). | |
610 | * | |
7ee24926 PA |
611 | * Problem is that the mptcp socket will be in |
612 | * ESTABLISHED state and will not have the SOCK_DEAD flag. | |
df1036da FW |
613 | * Both result in warnings from inet_sock_destruct. |
614 | */ | |
578c18ef | 615 | if ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { |
df1036da FW |
616 | sk->sk_state = TCP_CLOSE; |
617 | WARN_ON_ONCE(sk->sk_socket); | |
618 | sock_orphan(sk); | |
619 | } | |
620 | ||
5c8c1640 | 621 | mptcp_destroy_common(mptcp_sk(sk)); |
df1036da FW |
622 | inet_sock_destruct(sk); |
623 | } | |
624 | ||
9f5ca6a5 FW |
625 | static void mptcp_force_close(struct sock *sk) |
626 | { | |
490274b4 | 627 | /* the msk is not yet exposed to user-space */ |
9f5ca6a5 FW |
628 | inet_sk_state_store(sk, TCP_CLOSE); |
629 | sk_common_release(sk); | |
630 | } | |
631 | ||
4c8941de PA |
632 | static void subflow_ulp_fallback(struct sock *sk, |
633 | struct mptcp_subflow_context *old_ctx) | |
634 | { | |
635 | struct inet_connection_sock *icsk = inet_csk(sk); | |
636 | ||
637 | mptcp_subflow_tcp_fallback(sk, old_ctx); | |
638 | icsk->icsk_ulp_ops = NULL; | |
639 | rcu_assign_pointer(icsk->icsk_ulp_data, NULL); | |
640 | tcp_sk(sk)->is_mptcp = 0; | |
b19bc294 PA |
641 | |
642 | mptcp_subflow_ops_undo_override(sk); | |
4c8941de PA |
643 | } |
644 | ||
39884604 PA |
645 | static void subflow_drop_ctx(struct sock *ssk) |
646 | { | |
647 | struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(ssk); | |
648 | ||
649 | if (!ctx) | |
650 | return; | |
651 | ||
652 | subflow_ulp_fallback(ssk, ctx); | |
653 | if (ctx->conn) | |
654 | sock_put(ctx->conn); | |
655 | ||
656 | kfree_rcu(ctx, rcu); | |
657 | } | |
658 | ||
b93df08c PA |
659 | void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, |
660 | struct mptcp_options_received *mp_opt) | |
661 | { | |
662 | struct mptcp_sock *msk = mptcp_sk(subflow->conn); | |
663 | ||
664 | subflow->remote_key = mp_opt->sndr_key; | |
665 | subflow->fully_established = 1; | |
666 | subflow->can_ack = 1; | |
667 | WRITE_ONCE(msk->fully_established, true); | |
668 | } | |
669 | ||
cec37a6e PK |
670 | static struct sock *subflow_syn_recv_sock(const struct sock *sk, |
671 | struct sk_buff *skb, | |
672 | struct request_sock *req, | |
673 | struct dst_entry *dst, | |
674 | struct request_sock *req_unhash, | |
675 | bool *own_req) | |
676 | { | |
677 | struct mptcp_subflow_context *listener = mptcp_subflow_ctx(sk); | |
cc7972ea | 678 | struct mptcp_subflow_request_sock *subflow_req; |
cfde141e | 679 | struct mptcp_options_received mp_opt; |
9e365ff5 | 680 | bool fallback, fallback_is_fatal; |
58b09919 | 681 | struct sock *new_msk = NULL; |
cec37a6e PK |
682 | struct sock *child; |
683 | ||
684 | pr_debug("listener=%p, req=%p, conn=%p", listener, req, listener->conn); | |
685 | ||
74c7dfbe | 686 | /* After child creation we must look for MPC even when options |
9e365ff5 | 687 | * are not parsed |
cfde141e | 688 | */ |
74c7dfbe | 689 | mp_opt.suboptions = 0; |
9e365ff5 PA |
690 | |
691 | /* hopefully temporary handling for MP_JOIN+syncookie */ | |
692 | subflow_req = mptcp_subflow_rsk(req); | |
b7514694 | 693 | fallback_is_fatal = tcp_rsk(req)->is_mptcp && subflow_req->mp_join; |
9e365ff5 PA |
694 | fallback = !tcp_rsk(req)->is_mptcp; |
695 | if (fallback) | |
ae2dd716 FW |
696 | goto create_child; |
697 | ||
d22f4988 | 698 | /* if the sk is MP_CAPABLE, we try to fetch the client key */ |
cc7972ea | 699 | if (subflow_req->mp_capable) { |
06f9a435 PA |
700 | /* we can receive and accept an in-window, out-of-order pkt, |
701 | * which may not carry the MP_CAPABLE opt even on mptcp enabled | |
702 | * paths: always try to extract the peer key, and fallback | |
703 | * for packets missing it. | |
704 | * Even OoO DSS packets coming legitly after dropped or | |
705 | * reordered MPC will cause fallback, but we don't have other | |
706 | * options. | |
707 | */ | |
0799e21b | 708 | mptcp_get_options(skb, &mp_opt); |
74c7dfbe | 709 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) { |
4c8941de | 710 | fallback = true; |
58b09919 | 711 | goto create_child; |
d22f4988 | 712 | } |
58b09919 | 713 | |
cfde141e | 714 | new_msk = mptcp_sk_clone(listener->conn, &mp_opt, req); |
58b09919 | 715 | if (!new_msk) |
4c8941de | 716 | fallback = true; |
f296234c | 717 | } else if (subflow_req->mp_join) { |
0799e21b | 718 | mptcp_get_options(skb, &mp_opt); |
74c7dfbe PA |
719 | if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPJ) || |
720 | !subflow_hmac_valid(req, &mp_opt) || | |
d3ab7885 | 721 | !mptcp_can_accept_new_subflow(subflow_req->msk)) { |
fc518953 | 722 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKMAC); |
9e365ff5 | 723 | fallback = true; |
fc518953 | 724 | } |
cc7972ea | 725 | } |
cec37a6e | 726 | |
d22f4988 | 727 | create_child: |
cec37a6e PK |
728 | child = listener->icsk_af_ops->syn_recv_sock(sk, skb, req, dst, |
729 | req_unhash, own_req); | |
730 | ||
731 | if (child && *own_req) { | |
79c0949e PK |
732 | struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(child); |
733 | ||
90bf4513 PA |
734 | tcp_rsk(req)->drop_req = false; |
735 | ||
4c8941de PA |
736 | /* we need to fallback on ctx allocation failure and on pre-reqs |
737 | * checking above. In the latter scenario we additionally need | |
738 | * to reset the context to non MPTCP status. | |
79c0949e | 739 | */ |
4c8941de | 740 | if (!ctx || fallback) { |
dc87efdb FW |
741 | if (fallback_is_fatal) { |
742 | subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP); | |
729cd643 | 743 | goto dispose_child; |
dc87efdb | 744 | } |
4c8941de | 745 | |
39884604 | 746 | subflow_drop_ctx(child); |
58b09919 | 747 | goto out; |
f296234c | 748 | } |
79c0949e | 749 | |
df00b087 FW |
750 | /* ssk inherits options of listener sk */ |
751 | ctx->setsockopt_seq = listener->setsockopt_seq; | |
752 | ||
79c0949e | 753 | if (ctx->mp_capable) { |
b93df08c PA |
754 | /* this can't race with mptcp_close(), as the msk is |
755 | * not yet exposted to user-space | |
756 | */ | |
757 | inet_sk_state_store((void *)new_msk, TCP_ESTABLISHED); | |
758 | ||
5b950ff4 PA |
759 | /* record the newly created socket as the first msk |
760 | * subflow, but don't link it yet into conn_list | |
761 | */ | |
0397c6d8 PA |
762 | WRITE_ONCE(mptcp_sk(new_msk)->first, child); |
763 | ||
58b09919 PA |
764 | /* new mpc subflow takes ownership of the newly |
765 | * created mptcp socket | |
766 | */ | |
df1036da | 767 | new_msk->sk_destruct = mptcp_sock_destruct; |
df00b087 | 768 | mptcp_sk(new_msk)->setsockopt_seq = ctx->setsockopt_seq; |
6c714f1b | 769 | mptcp_pm_new_connection(mptcp_sk(new_msk), child, 1); |
2c5ebd00 | 770 | mptcp_token_accept(subflow_req, mptcp_sk(new_msk)); |
58b09919 PA |
771 | ctx->conn = new_msk; |
772 | new_msk = NULL; | |
fca5c82c PA |
773 | |
774 | /* with OoO packets we can reach here without ingress | |
775 | * mpc option | |
776 | */ | |
74c7dfbe | 777 | if (mp_opt.suboptions & OPTIONS_MPTCP_MPC) |
b93df08c | 778 | mptcp_subflow_fully_established(ctx, &mp_opt); |
f296234c PK |
779 | } else if (ctx->mp_join) { |
780 | struct mptcp_sock *owner; | |
781 | ||
8fd4de12 | 782 | owner = subflow_req->msk; |
dc87efdb FW |
783 | if (!owner) { |
784 | subflow_add_reset_reason(skb, MPTCP_RST_EPROHIBIT); | |
729cd643 | 785 | goto dispose_child; |
dc87efdb | 786 | } |
f296234c | 787 | |
8fd4de12 PA |
788 | /* move the msk reference ownership to the subflow */ |
789 | subflow_req->msk = NULL; | |
f296234c | 790 | ctx->conn = (struct sock *)owner; |
5bc56388 GT |
791 | |
792 | if (subflow_use_different_sport(owner, sk)) { | |
793 | pr_debug("ack inet_sport=%d %d", | |
794 | ntohs(inet_sk(sk)->inet_sport), | |
795 | ntohs(inet_sk((struct sock *)owner)->inet_sport)); | |
2fbdd9ea GT |
796 | if (!mptcp_pm_sport_in_anno_list(owner, sk)) { |
797 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MISMATCHPORTACKRX); | |
9238e900 | 798 | goto dispose_child; |
2fbdd9ea GT |
799 | } |
800 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINPORTACKRX); | |
5bc56388 | 801 | } |
9238e900 GT |
802 | |
803 | if (!mptcp_finish_join(child)) | |
804 | goto dispose_child; | |
805 | ||
806 | SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKRX); | |
807 | tcp_rsk(req)->drop_req = true; | |
cec37a6e PK |
808 | } |
809 | } | |
810 | ||
58b09919 PA |
811 | out: |
812 | /* dispose of the left over mptcp master, if any */ | |
813 | if (unlikely(new_msk)) | |
9f5ca6a5 | 814 | mptcp_force_close(new_msk); |
4c8941de PA |
815 | |
816 | /* check for expected invariant - should never trigger, just help | |
817 | * catching eariler subtle bugs | |
818 | */ | |
ac2b47fb | 819 | WARN_ON_ONCE(child && *own_req && tcp_sk(child)->is_mptcp && |
4c8941de PA |
820 | (!mptcp_subflow_ctx(child) || |
821 | !mptcp_subflow_ctx(child)->conn)); | |
cec37a6e | 822 | return child; |
f296234c | 823 | |
729cd643 | 824 | dispose_child: |
39884604 | 825 | subflow_drop_ctx(child); |
729cd643 | 826 | tcp_rsk(req)->drop_req = true; |
729cd643 | 827 | inet_csk_prepare_for_destroy_sock(child); |
f296234c | 828 | tcp_done(child); |
97e61751 | 829 | req->rsk_ops->send_reset(sk, skb); |
729cd643 PA |
830 | |
831 | /* The last child reference will be released by the caller */ | |
832 | return child; | |
cec37a6e PK |
833 | } |
834 | ||
51fa7f8e | 835 | static struct inet_connection_sock_af_ops subflow_specific __ro_after_init; |
b19bc294 | 836 | static struct proto tcp_prot_override; |
cec37a6e | 837 | |
648ef4b8 MM |
838 | enum mapping_status { |
839 | MAPPING_OK, | |
840 | MAPPING_INVALID, | |
841 | MAPPING_EMPTY, | |
e1ff9e82 DC |
842 | MAPPING_DATA_FIN, |
843 | MAPPING_DUMMY | |
648ef4b8 MM |
844 | }; |
845 | ||
61e71022 | 846 | static void dbg_bad_map(struct mptcp_subflow_context *subflow, u32 ssn) |
648ef4b8 | 847 | { |
61e71022 PA |
848 | pr_debug("Bad mapping: ssn=%d map_seq=%d map_data_len=%d", |
849 | ssn, subflow->map_subflow_seq, subflow->map_data_len); | |
648ef4b8 MM |
850 | } |
851 | ||
852 | static bool skb_is_fully_mapped(struct sock *ssk, struct sk_buff *skb) | |
853 | { | |
854 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
855 | unsigned int skb_consumed; | |
856 | ||
857 | skb_consumed = tcp_sk(ssk)->copied_seq - TCP_SKB_CB(skb)->seq; | |
858 | if (WARN_ON_ONCE(skb_consumed >= skb->len)) | |
859 | return true; | |
860 | ||
861 | return skb->len - skb_consumed <= subflow->map_data_len - | |
862 | mptcp_subflow_get_map_offset(subflow); | |
863 | } | |
864 | ||
865 | static bool validate_mapping(struct sock *ssk, struct sk_buff *skb) | |
866 | { | |
867 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
868 | u32 ssn = tcp_sk(ssk)->copied_seq - subflow->ssn_offset; | |
869 | ||
870 | if (unlikely(before(ssn, subflow->map_subflow_seq))) { | |
871 | /* Mapping covers data later in the subflow stream, | |
872 | * currently unsupported. | |
873 | */ | |
61e71022 | 874 | dbg_bad_map(subflow, ssn); |
648ef4b8 MM |
875 | return false; |
876 | } | |
877 | if (unlikely(!before(ssn, subflow->map_subflow_seq + | |
878 | subflow->map_data_len))) { | |
879 | /* Mapping does covers past subflow data, invalid */ | |
61e71022 | 880 | dbg_bad_map(subflow, ssn); |
648ef4b8 MM |
881 | return false; |
882 | } | |
883 | return true; | |
884 | } | |
885 | ||
dd8bcd17 PA |
886 | static enum mapping_status validate_data_csum(struct sock *ssk, struct sk_buff *skb, |
887 | bool csum_reqd) | |
888 | { | |
889 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
dd8bcd17 | 890 | u32 offset, seq, delta; |
8401e87f | 891 | u16 csum; |
dd8bcd17 PA |
892 | int len; |
893 | ||
894 | if (!csum_reqd) | |
895 | return MAPPING_OK; | |
896 | ||
897 | /* mapping already validated on previous traversal */ | |
898 | if (subflow->map_csum_len == subflow->map_data_len) | |
899 | return MAPPING_OK; | |
900 | ||
901 | /* traverse the receive queue, ensuring it contains a full | |
902 | * DSS mapping and accumulating the related csum. | |
903 | * Preserve the accoumlate csum across multiple calls, to compute | |
904 | * the csum only once | |
905 | */ | |
906 | delta = subflow->map_data_len - subflow->map_csum_len; | |
907 | for (;;) { | |
908 | seq = tcp_sk(ssk)->copied_seq + subflow->map_csum_len; | |
909 | offset = seq - TCP_SKB_CB(skb)->seq; | |
910 | ||
911 | /* if the current skb has not been accounted yet, csum its contents | |
912 | * up to the amount covered by the current DSS | |
913 | */ | |
914 | if (offset < skb->len) { | |
915 | __wsum csum; | |
916 | ||
917 | len = min(skb->len - offset, delta); | |
918 | csum = skb_checksum(skb, offset, len, 0); | |
919 | subflow->map_data_csum = csum_block_add(subflow->map_data_csum, csum, | |
920 | subflow->map_csum_len); | |
921 | ||
922 | delta -= len; | |
923 | subflow->map_csum_len += len; | |
924 | } | |
925 | if (delta == 0) | |
926 | break; | |
927 | ||
928 | if (skb_queue_is_last(&ssk->sk_receive_queue, skb)) { | |
929 | /* if this subflow is closed, the partial mapping | |
930 | * will be never completed; flush the pending skbs, so | |
931 | * that subflow_sched_work_if_closed() can kick in | |
932 | */ | |
933 | if (unlikely(ssk->sk_state == TCP_CLOSE)) | |
934 | while ((skb = skb_peek(&ssk->sk_receive_queue))) | |
935 | sk_eat_skb(ssk, skb); | |
936 | ||
937 | /* not enough data to validate the csum */ | |
938 | return MAPPING_EMPTY; | |
939 | } | |
940 | ||
941 | /* the DSS mapping for next skbs will be validated later, | |
942 | * when a get_mapping_status call will process such skb | |
943 | */ | |
944 | skb = skb->next; | |
945 | } | |
946 | ||
947 | /* note that 'map_data_len' accounts only for the carried data, does | |
948 | * not include the eventual seq increment due to the data fin, | |
949 | * while the pseudo header requires the original DSS data len, | |
950 | * including that | |
951 | */ | |
8401e87f GT |
952 | csum = __mptcp_make_csum(subflow->map_seq, |
953 | subflow->map_subflow_seq, | |
954 | subflow->map_data_len + subflow->map_data_fin, | |
955 | subflow->map_data_csum); | |
956 | if (unlikely(csum)) { | |
fe3ab1cb | 957 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DATACSUMERR); |
478d7700 | 958 | subflow->send_mp_fail = 1; |
eb7f3365 | 959 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_MPFAILTX); |
dd8bcd17 | 960 | return subflow->mp_join ? MAPPING_INVALID : MAPPING_DUMMY; |
fe3ab1cb | 961 | } |
dd8bcd17 PA |
962 | |
963 | return MAPPING_OK; | |
964 | } | |
965 | ||
43b54c6e MM |
966 | static enum mapping_status get_mapping_status(struct sock *ssk, |
967 | struct mptcp_sock *msk) | |
648ef4b8 MM |
968 | { |
969 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
dd8bcd17 | 970 | bool csum_reqd = READ_ONCE(msk->csum_enabled); |
49fa1919 | 971 | struct sock *sk = (struct sock *)msk; |
648ef4b8 MM |
972 | struct mptcp_ext *mpext; |
973 | struct sk_buff *skb; | |
974 | u16 data_len; | |
975 | u64 map_seq; | |
976 | ||
977 | skb = skb_peek(&ssk->sk_receive_queue); | |
978 | if (!skb) | |
979 | return MAPPING_EMPTY; | |
980 | ||
e1ff9e82 DC |
981 | if (mptcp_check_fallback(ssk)) |
982 | return MAPPING_DUMMY; | |
983 | ||
648ef4b8 MM |
984 | mpext = mptcp_get_ext(skb); |
985 | if (!mpext || !mpext->use_map) { | |
986 | if (!subflow->map_valid && !skb->len) { | |
987 | /* the TCP stack deliver 0 len FIN pkt to the receive | |
988 | * queue, that is the only 0len pkts ever expected here, | |
989 | * and we can admit no mapping only for 0 len pkts | |
990 | */ | |
991 | if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) | |
992 | WARN_ONCE(1, "0len seq %d:%d flags %x", | |
993 | TCP_SKB_CB(skb)->seq, | |
994 | TCP_SKB_CB(skb)->end_seq, | |
995 | TCP_SKB_CB(skb)->tcp_flags); | |
996 | sk_eat_skb(ssk, skb); | |
997 | return MAPPING_EMPTY; | |
998 | } | |
999 | ||
1000 | if (!subflow->map_valid) | |
1001 | return MAPPING_INVALID; | |
1002 | ||
1003 | goto validate_seq; | |
1004 | } | |
1005 | ||
0918e34b | 1006 | trace_get_mapping_status(mpext); |
648ef4b8 MM |
1007 | |
1008 | data_len = mpext->data_len; | |
1009 | if (data_len == 0) { | |
f8d4bcac | 1010 | pr_debug("infinite mapping received"); |
fc518953 | 1011 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX); |
f8d4bcac | 1012 | subflow->map_data_len = 0; |
49fa1919 GT |
1013 | if (sk && inet_sk_state_load(sk) != TCP_CLOSE) { |
1014 | mptcp_data_lock(sk); | |
1015 | if (inet_sk_state_load(sk) != TCP_CLOSE) | |
1016 | sk_stop_timer(sk, &sk->sk_timer); | |
1017 | mptcp_data_unlock(sk); | |
1018 | } | |
648ef4b8 MM |
1019 | return MAPPING_INVALID; |
1020 | } | |
1021 | ||
1022 | if (mpext->data_fin == 1) { | |
1023 | if (data_len == 1) { | |
1a49b2c2 MM |
1024 | bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq, |
1025 | mpext->dsn64); | |
43b54c6e | 1026 | pr_debug("DATA_FIN with no payload seq=%llu", mpext->data_seq); |
648ef4b8 MM |
1027 | if (subflow->map_valid) { |
1028 | /* A DATA_FIN might arrive in a DSS | |
1029 | * option before the previous mapping | |
1030 | * has been fully consumed. Continue | |
1031 | * handling the existing mapping. | |
1032 | */ | |
1033 | skb_ext_del(skb, SKB_EXT_MPTCP); | |
1034 | return MAPPING_OK; | |
1035 | } else { | |
ef59b195 MM |
1036 | if (updated && schedule_work(&msk->work)) |
1037 | sock_hold((struct sock *)msk); | |
1038 | ||
648ef4b8 MM |
1039 | return MAPPING_DATA_FIN; |
1040 | } | |
43b54c6e | 1041 | } else { |
017512a0 | 1042 | u64 data_fin_seq = mpext->data_seq + data_len - 1; |
1a49b2c2 MM |
1043 | |
1044 | /* If mpext->data_seq is a 32-bit value, data_fin_seq | |
1045 | * must also be limited to 32 bits. | |
1046 | */ | |
1047 | if (!mpext->dsn64) | |
1048 | data_fin_seq &= GENMASK_ULL(31, 0); | |
1049 | ||
1050 | mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64); | |
1051 | pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d", | |
1052 | data_fin_seq, mpext->dsn64); | |
648ef4b8 MM |
1053 | } |
1054 | ||
1055 | /* Adjust for DATA_FIN using 1 byte of sequence space */ | |
1056 | data_len--; | |
1057 | } | |
1058 | ||
5957a890 | 1059 | map_seq = mptcp_expand_seq(READ_ONCE(msk->ack_seq), mpext->data_seq, mpext->dsn64); |
37198e93 | 1060 | WRITE_ONCE(mptcp_sk(subflow->conn)->use_64bit_ack, !!mpext->dsn64); |
648ef4b8 MM |
1061 | |
1062 | if (subflow->map_valid) { | |
1063 | /* Allow replacing only with an identical map */ | |
1064 | if (subflow->map_seq == map_seq && | |
1065 | subflow->map_subflow_seq == mpext->subflow_seq && | |
dd8bcd17 PA |
1066 | subflow->map_data_len == data_len && |
1067 | subflow->map_csum_reqd == mpext->csum_reqd) { | |
648ef4b8 | 1068 | skb_ext_del(skb, SKB_EXT_MPTCP); |
dd8bcd17 | 1069 | goto validate_csum; |
648ef4b8 MM |
1070 | } |
1071 | ||
1072 | /* If this skb data are fully covered by the current mapping, | |
1073 | * the new map would need caching, which is not supported | |
1074 | */ | |
fc518953 FW |
1075 | if (skb_is_fully_mapped(ssk, skb)) { |
1076 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSNOMATCH); | |
648ef4b8 | 1077 | return MAPPING_INVALID; |
fc518953 | 1078 | } |
648ef4b8 MM |
1079 | |
1080 | /* will validate the next map after consuming the current one */ | |
dd8bcd17 | 1081 | goto validate_csum; |
648ef4b8 MM |
1082 | } |
1083 | ||
1084 | subflow->map_seq = map_seq; | |
1085 | subflow->map_subflow_seq = mpext->subflow_seq; | |
1086 | subflow->map_data_len = data_len; | |
1087 | subflow->map_valid = 1; | |
dd8bcd17 | 1088 | subflow->map_data_fin = mpext->data_fin; |
d22f4988 | 1089 | subflow->mpc_map = mpext->mpc_map; |
dd8bcd17 PA |
1090 | subflow->map_csum_reqd = mpext->csum_reqd; |
1091 | subflow->map_csum_len = 0; | |
1092 | subflow->map_data_csum = csum_unfold(mpext->csum); | |
1093 | ||
1094 | /* Cfr RFC 8684 Section 3.3.0 */ | |
1095 | if (unlikely(subflow->map_csum_reqd != csum_reqd)) | |
1096 | return MAPPING_INVALID; | |
1097 | ||
1098 | pr_debug("new map seq=%llu subflow_seq=%u data_len=%u csum=%d:%u", | |
648ef4b8 | 1099 | subflow->map_seq, subflow->map_subflow_seq, |
dd8bcd17 PA |
1100 | subflow->map_data_len, subflow->map_csum_reqd, |
1101 | subflow->map_data_csum); | |
648ef4b8 MM |
1102 | |
1103 | validate_seq: | |
1104 | /* we revalidate valid mapping on new skb, because we must ensure | |
1105 | * the current skb is completely covered by the available mapping | |
1106 | */ | |
06285da9 PA |
1107 | if (!validate_mapping(ssk, skb)) { |
1108 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSTCPMISMATCH); | |
648ef4b8 | 1109 | return MAPPING_INVALID; |
06285da9 | 1110 | } |
648ef4b8 MM |
1111 | |
1112 | skb_ext_del(skb, SKB_EXT_MPTCP); | |
dd8bcd17 PA |
1113 | |
1114 | validate_csum: | |
1115 | return validate_data_csum(ssk, skb, csum_reqd); | |
648ef4b8 MM |
1116 | } |
1117 | ||
04e4cd4f | 1118 | static void mptcp_subflow_discard_data(struct sock *ssk, struct sk_buff *skb, |
1d39cd8c | 1119 | u64 limit) |
6719331c PA |
1120 | { |
1121 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
04e4cd4f PA |
1122 | bool fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN; |
1123 | u32 incr; | |
1124 | ||
1125 | incr = limit >= skb->len ? skb->len + fin : limit; | |
1126 | ||
1127 | pr_debug("discarding=%d len=%d seq=%d", incr, skb->len, | |
1128 | subflow->map_subflow_seq); | |
06242e44 | 1129 | MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DUPDATA); |
04e4cd4f PA |
1130 | tcp_sk(ssk)->copied_seq += incr; |
1131 | if (!before(tcp_sk(ssk)->copied_seq, TCP_SKB_CB(skb)->end_seq)) | |
1132 | sk_eat_skb(ssk, skb); | |
1133 | if (mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len) | |
1134 | subflow->map_valid = 0; | |
6719331c PA |
1135 | } |
1136 | ||
40947e13 FW |
1137 | /* sched mptcp worker to remove the subflow if no more data is pending */ |
1138 | static void subflow_sched_work_if_closed(struct mptcp_sock *msk, struct sock *ssk) | |
1139 | { | |
1140 | struct sock *sk = (struct sock *)msk; | |
1141 | ||
1142 | if (likely(ssk->sk_state != TCP_CLOSE)) | |
1143 | return; | |
1144 | ||
1145 | if (skb_queue_empty(&ssk->sk_receive_queue) && | |
1146 | !test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags)) { | |
1147 | sock_hold(sk); | |
1148 | if (!schedule_work(&msk->work)) | |
1149 | sock_put(sk); | |
1150 | } | |
1151 | } | |
1152 | ||
648ef4b8 MM |
1153 | static bool subflow_check_data_avail(struct sock *ssk) |
1154 | { | |
1155 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
1156 | enum mapping_status status; | |
1157 | struct mptcp_sock *msk; | |
1158 | struct sk_buff *skb; | |
1159 | ||
47bebdf3 | 1160 | if (!skb_peek(&ssk->sk_receive_queue)) |
ea56dcb4 | 1161 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA); |
648ef4b8 MM |
1162 | if (subflow->data_avail) |
1163 | return true; | |
1164 | ||
648ef4b8 MM |
1165 | msk = mptcp_sk(subflow->conn); |
1166 | for (;;) { | |
648ef4b8 MM |
1167 | u64 ack_seq; |
1168 | u64 old_ack; | |
1169 | ||
43b54c6e | 1170 | status = get_mapping_status(ssk, msk); |
d96a838a | 1171 | trace_subflow_check_data_avail(status, skb_peek(&ssk->sk_receive_queue)); |
dea2b1ea PA |
1172 | if (unlikely(status == MAPPING_INVALID)) |
1173 | goto fallback; | |
1174 | ||
1175 | if (unlikely(status == MAPPING_DUMMY)) | |
1176 | goto fallback; | |
648ef4b8 MM |
1177 | |
1178 | if (status != MAPPING_OK) | |
40947e13 | 1179 | goto no_data; |
648ef4b8 MM |
1180 | |
1181 | skb = skb_peek(&ssk->sk_receive_queue); | |
1182 | if (WARN_ON_ONCE(!skb)) | |
40947e13 | 1183 | goto no_data; |
648ef4b8 | 1184 | |
d22f4988 CP |
1185 | /* if msk lacks the remote key, this subflow must provide an |
1186 | * MP_CAPABLE-based mapping | |
1187 | */ | |
1188 | if (unlikely(!READ_ONCE(msk->can_ack))) { | |
dea2b1ea PA |
1189 | if (!subflow->mpc_map) |
1190 | goto fallback; | |
d22f4988 CP |
1191 | WRITE_ONCE(msk->remote_key, subflow->remote_key); |
1192 | WRITE_ONCE(msk->ack_seq, subflow->map_seq); | |
1193 | WRITE_ONCE(msk->can_ack, true); | |
1194 | } | |
1195 | ||
648ef4b8 MM |
1196 | old_ack = READ_ONCE(msk->ack_seq); |
1197 | ack_seq = mptcp_subflow_get_mapped_dsn(subflow); | |
1198 | pr_debug("msk ack_seq=%llx subflow ack_seq=%llx", old_ack, | |
1199 | ack_seq); | |
99d1055c PA |
1200 | if (unlikely(before64(ack_seq, old_ack))) { |
1201 | mptcp_subflow_discard_data(ssk, skb, old_ack - ack_seq); | |
1202 | continue; | |
47bebdf3 | 1203 | } |
648ef4b8 | 1204 | |
99d1055c PA |
1205 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL); |
1206 | break; | |
648ef4b8 MM |
1207 | } |
1208 | return true; | |
1209 | ||
40947e13 FW |
1210 | no_data: |
1211 | subflow_sched_work_if_closed(msk, ssk); | |
1212 | return false; | |
dea2b1ea PA |
1213 | |
1214 | fallback: | |
0348c690 GT |
1215 | if (!__mptcp_check_fallback(msk)) { |
1216 | /* RFC 8684 section 3.7. */ | |
1217 | if (subflow->send_mp_fail) { | |
0530020a GT |
1218 | if (mptcp_has_another_subflow(ssk) || |
1219 | !READ_ONCE(msk->allow_infinite_fallback)) { | |
0348c690 GT |
1220 | ssk->sk_err = EBADMSG; |
1221 | tcp_set_state(ssk, TCP_CLOSE); | |
1222 | subflow->reset_transient = 0; | |
1223 | subflow->reset_reason = MPTCP_RST_EMIDDLEBOX; | |
1224 | tcp_send_active_reset(ssk, GFP_ATOMIC); | |
1225 | while ((skb = skb_peek(&ssk->sk_receive_queue))) | |
1226 | sk_eat_skb(ssk, skb); | |
9c81be0d GT |
1227 | } else { |
1228 | WRITE_ONCE(subflow->mp_fail_response_expect, true); | |
49fa1919 GT |
1229 | /* The data lock is acquired in __mptcp_move_skbs() */ |
1230 | sk_reset_timer((struct sock *)msk, | |
1231 | &((struct sock *)msk)->sk_timer, | |
1232 | jiffies + TCP_RTO_MAX); | |
0348c690 GT |
1233 | } |
1234 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA); | |
1235 | return true; | |
1236 | } | |
1237 | ||
f8d4bcac | 1238 | if ((subflow->mp_join || subflow->fully_established) && subflow->map_data_len) { |
0348c690 GT |
1239 | /* fatal protocol error, close the socket. |
1240 | * subflow_error_report() will introduce the appropriate barriers | |
1241 | */ | |
1761fed2 GT |
1242 | ssk->sk_err = EBADMSG; |
1243 | tcp_set_state(ssk, TCP_CLOSE); | |
1244 | subflow->reset_transient = 0; | |
0348c690 | 1245 | subflow->reset_reason = MPTCP_RST_EMPTCP; |
1761fed2 | 1246 | tcp_send_active_reset(ssk, GFP_ATOMIC); |
0348c690 GT |
1247 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA); |
1248 | return false; | |
478d7700 | 1249 | } |
478d7700 | 1250 | |
0348c690 | 1251 | __mptcp_do_fallback(msk); |
dea2b1ea PA |
1252 | } |
1253 | ||
dea2b1ea PA |
1254 | skb = skb_peek(&ssk->sk_receive_queue); |
1255 | subflow->map_valid = 1; | |
1256 | subflow->map_seq = READ_ONCE(msk->ack_seq); | |
1257 | subflow->map_data_len = skb->len; | |
1258 | subflow->map_subflow_seq = tcp_sk(ssk)->copied_seq - subflow->ssn_offset; | |
99d1055c | 1259 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL); |
dea2b1ea | 1260 | return true; |
648ef4b8 MM |
1261 | } |
1262 | ||
1263 | bool mptcp_subflow_data_available(struct sock *sk) | |
1264 | { | |
1265 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
648ef4b8 MM |
1266 | |
1267 | /* check if current mapping is still valid */ | |
1268 | if (subflow->map_valid && | |
1269 | mptcp_subflow_get_map_offset(subflow) >= subflow->map_data_len) { | |
1270 | subflow->map_valid = 0; | |
ea56dcb4 | 1271 | WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA); |
648ef4b8 MM |
1272 | |
1273 | pr_debug("Done with mapping: seq=%u data_len=%u", | |
1274 | subflow->map_subflow_seq, | |
1275 | subflow->map_data_len); | |
1276 | } | |
1277 | ||
47bebdf3 | 1278 | return subflow_check_data_avail(sk); |
648ef4b8 MM |
1279 | } |
1280 | ||
071c8ed6 FW |
1281 | /* If ssk has an mptcp parent socket, use the mptcp rcvbuf occupancy, |
1282 | * not the ssk one. | |
1283 | * | |
1284 | * In mptcp, rwin is about the mptcp-level connection data. | |
1285 | * | |
1286 | * Data that is still on the ssk rx queue can thus be ignored, | |
55320b82 | 1287 | * as far as mptcp peer is concerned that data is still inflight. |
071c8ed6 FW |
1288 | * DSS ACK is updated when skb is moved to the mptcp rx queue. |
1289 | */ | |
1290 | void mptcp_space(const struct sock *ssk, int *space, int *full_space) | |
1291 | { | |
1292 | const struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
1293 | const struct sock *sk = subflow->conn; | |
1294 | ||
ea4ca586 | 1295 | *space = __mptcp_space(sk); |
071c8ed6 FW |
1296 | *full_space = tcp_full_space(sk); |
1297 | } | |
1298 | ||
15cc1045 PA |
1299 | void __mptcp_error_report(struct sock *sk) |
1300 | { | |
1301 | struct mptcp_subflow_context *subflow; | |
1302 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1303 | ||
1304 | mptcp_for_each_subflow(msk, subflow) { | |
1305 | struct sock *ssk = mptcp_subflow_tcp_sock(subflow); | |
1306 | int err = sock_error(ssk); | |
1307 | ||
1308 | if (!err) | |
1309 | continue; | |
1310 | ||
1311 | /* only propagate errors on fallen-back sockets or | |
1312 | * on MPC connect | |
1313 | */ | |
1314 | if (sk->sk_state != TCP_SYN_SENT && !__mptcp_check_fallback(msk)) | |
1315 | continue; | |
1316 | ||
1317 | inet_sk_state_store(sk, inet_sk_state_load(ssk)); | |
1318 | sk->sk_err = -err; | |
1319 | ||
1320 | /* This barrier is coupled with smp_rmb() in mptcp_poll() */ | |
1321 | smp_wmb(); | |
e3ae2365 | 1322 | sk_error_report(sk); |
15cc1045 PA |
1323 | break; |
1324 | } | |
1325 | } | |
1326 | ||
1327 | static void subflow_error_report(struct sock *ssk) | |
1328 | { | |
1329 | struct sock *sk = mptcp_subflow_ctx(ssk)->conn; | |
1330 | ||
1331 | mptcp_data_lock(sk); | |
1332 | if (!sock_owned_by_user(sk)) | |
1333 | __mptcp_error_report(sk); | |
1334 | else | |
e9d09bac | 1335 | __set_bit(MPTCP_ERROR_REPORT, &mptcp_sk(sk)->cb_flags); |
15cc1045 PA |
1336 | mptcp_data_unlock(sk); |
1337 | } | |
1338 | ||
499ada50 PA |
1339 | static void subflow_data_ready(struct sock *sk) |
1340 | { | |
1341 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
1342 | u16 state = 1 << inet_sk_state_load(sk); | |
1343 | struct sock *parent = subflow->conn; | |
1344 | struct mptcp_sock *msk; | |
1345 | ||
1346 | msk = mptcp_sk(parent); | |
1347 | if (state & TCPF_LISTEN) { | |
1348 | /* MPJ subflow are removed from accept queue before reaching here, | |
1349 | * avoid stray wakeups | |
1350 | */ | |
1351 | if (reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue)) | |
1352 | return; | |
1353 | ||
499ada50 PA |
1354 | parent->sk_data_ready(parent); |
1355 | return; | |
1356 | } | |
1357 | ||
1358 | WARN_ON_ONCE(!__mptcp_check_fallback(msk) && !subflow->mp_capable && | |
1359 | !subflow->mp_join && !(state & TCPF_CLOSE)); | |
1360 | ||
1361 | if (mptcp_subflow_data_available(sk)) | |
1362 | mptcp_data_ready(parent, sk); | |
1363 | else if (unlikely(sk->sk_err)) | |
1364 | subflow_error_report(sk); | |
1365 | } | |
1366 | ||
1367 | static void subflow_write_space(struct sock *ssk) | |
1368 | { | |
1369 | struct sock *sk = mptcp_subflow_ctx(ssk)->conn; | |
1370 | ||
1371 | mptcp_propagate_sndbuf(sk, ssk); | |
1372 | mptcp_write_space(sk); | |
1373 | } | |
1374 | ||
51fa7f8e | 1375 | static const struct inet_connection_sock_af_ops * |
cec37a6e PK |
1376 | subflow_default_af_ops(struct sock *sk) |
1377 | { | |
1378 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1379 | if (sk->sk_family == AF_INET6) | |
1380 | return &subflow_v6_specific; | |
1381 | #endif | |
1382 | return &subflow_specific; | |
1383 | } | |
1384 | ||
cec37a6e | 1385 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
31484d56 GU |
1386 | void mptcpv6_handle_mapped(struct sock *sk, bool mapped) |
1387 | { | |
cec37a6e PK |
1388 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); |
1389 | struct inet_connection_sock *icsk = inet_csk(sk); | |
51fa7f8e | 1390 | const struct inet_connection_sock_af_ops *target; |
cec37a6e PK |
1391 | |
1392 | target = mapped ? &subflow_v6m_specific : subflow_default_af_ops(sk); | |
1393 | ||
1394 | pr_debug("subflow=%p family=%d ops=%p target=%p mapped=%d", | |
edc7e489 | 1395 | subflow, sk->sk_family, icsk->icsk_af_ops, target, mapped); |
cec37a6e PK |
1396 | |
1397 | if (likely(icsk->icsk_af_ops == target)) | |
1398 | return; | |
1399 | ||
1400 | subflow->icsk_af_ops = icsk->icsk_af_ops; | |
1401 | icsk->icsk_af_ops = target; | |
cec37a6e | 1402 | } |
31484d56 | 1403 | #endif |
cec37a6e | 1404 | |
1729cf18 GT |
1405 | void mptcp_info2sockaddr(const struct mptcp_addr_info *info, |
1406 | struct sockaddr_storage *addr, | |
1407 | unsigned short family) | |
ec3edaa7 PK |
1408 | { |
1409 | memset(addr, 0, sizeof(*addr)); | |
50a13bc3 | 1410 | addr->ss_family = family; |
ec3edaa7 PK |
1411 | if (addr->ss_family == AF_INET) { |
1412 | struct sockaddr_in *in_addr = (struct sockaddr_in *)addr; | |
1413 | ||
50a13bc3 MB |
1414 | if (info->family == AF_INET) |
1415 | in_addr->sin_addr = info->addr; | |
1416 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1417 | else if (ipv6_addr_v4mapped(&info->addr6)) | |
1418 | in_addr->sin_addr.s_addr = info->addr6.s6_addr32[3]; | |
1419 | #endif | |
ec3edaa7 PK |
1420 | in_addr->sin_port = info->port; |
1421 | } | |
1422 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1423 | else if (addr->ss_family == AF_INET6) { | |
1424 | struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)addr; | |
1425 | ||
50a13bc3 MB |
1426 | if (info->family == AF_INET) |
1427 | ipv6_addr_set_v4mapped(info->addr.s_addr, | |
1428 | &in6_addr->sin6_addr); | |
1429 | else | |
1430 | in6_addr->sin6_addr = info->addr6; | |
ec3edaa7 PK |
1431 | in6_addr->sin6_port = info->port; |
1432 | } | |
1433 | #endif | |
1434 | } | |
1435 | ||
ef0da3b8 | 1436 | int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, |
ee285257 | 1437 | const struct mptcp_addr_info *remote) |
ec3edaa7 PK |
1438 | { |
1439 | struct mptcp_sock *msk = mptcp_sk(sk); | |
1440 | struct mptcp_subflow_context *subflow; | |
1441 | struct sockaddr_storage addr; | |
2ff0e566 | 1442 | int remote_id = remote->id; |
6bad912b | 1443 | int local_id = loc->id; |
ec3edaa7 | 1444 | struct socket *sf; |
6bad912b | 1445 | struct sock *ssk; |
ec3edaa7 PK |
1446 | u32 remote_token; |
1447 | int addrlen; | |
ee285257 GT |
1448 | int ifindex; |
1449 | u8 flags; | |
ec3edaa7 PK |
1450 | int err; |
1451 | ||
b93df08c | 1452 | if (!mptcp_is_fully_established(sk)) |
ec3edaa7 PK |
1453 | return -ENOTCONN; |
1454 | ||
1455 | err = mptcp_subflow_create_socket(sk, &sf); | |
1456 | if (err) | |
1457 | return err; | |
1458 | ||
6bad912b PA |
1459 | ssk = sf->sk; |
1460 | subflow = mptcp_subflow_ctx(ssk); | |
1461 | do { | |
1462 | get_random_bytes(&subflow->local_nonce, sizeof(u32)); | |
1463 | } while (!subflow->local_nonce); | |
1464 | ||
4cf86ae8 PA |
1465 | if (local_id) |
1466 | subflow_set_local_id(subflow, local_id); | |
6bad912b | 1467 | |
ee285257 GT |
1468 | mptcp_pm_get_flags_and_ifindex_by_id(sock_net(sk), local_id, |
1469 | &flags, &ifindex); | |
ec3edaa7 PK |
1470 | subflow->remote_key = msk->remote_key; |
1471 | subflow->local_key = msk->local_key; | |
1472 | subflow->token = msk->token; | |
50a13bc3 | 1473 | mptcp_info2sockaddr(loc, &addr, ssk->sk_family); |
ec3edaa7 PK |
1474 | |
1475 | addrlen = sizeof(struct sockaddr_in); | |
1476 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
50a13bc3 | 1477 | if (addr.ss_family == AF_INET6) |
ec3edaa7 PK |
1478 | addrlen = sizeof(struct sockaddr_in6); |
1479 | #endif | |
c9406a23 FW |
1480 | mptcp_sockopt_sync(msk, ssk); |
1481 | ||
daa83ab0 | 1482 | ssk->sk_bound_dev_if = ifindex; |
ec3edaa7 PK |
1483 | err = kernel_bind(sf, (struct sockaddr *)&addr, addrlen); |
1484 | if (err) | |
1485 | goto failed; | |
1486 | ||
1487 | mptcp_crypto_key_sha(subflow->remote_key, &remote_token, NULL); | |
2ff0e566 GT |
1488 | pr_debug("msk=%p remote_token=%u local_id=%d remote_id=%d", msk, |
1489 | remote_token, local_id, remote_id); | |
ec3edaa7 | 1490 | subflow->remote_token = remote_token; |
2ff0e566 | 1491 | subflow->remote_id = remote_id; |
ec3edaa7 | 1492 | subflow->request_join = 1; |
daa83ab0 | 1493 | subflow->request_bkup = !!(flags & MPTCP_PM_ADDR_FLAG_BACKUP); |
50a13bc3 | 1494 | mptcp_info2sockaddr(remote, &addr, ssk->sk_family); |
ec3edaa7 | 1495 | |
3e501490 PA |
1496 | sock_hold(ssk); |
1497 | list_add_tail(&subflow->node, &msk->conn_list); | |
ec3edaa7 PK |
1498 | err = kernel_connect(sf, (struct sockaddr *)&addr, addrlen, O_NONBLOCK); |
1499 | if (err && err != -EINPROGRESS) | |
5b950ff4 | 1500 | goto failed_unlink; |
ec3edaa7 | 1501 | |
866f26f2 PA |
1502 | /* discard the subflow socket */ |
1503 | mptcp_sock_graft(ssk, sk->sk_socket); | |
1504 | iput(SOCK_INODE(sf)); | |
0530020a | 1505 | WRITE_ONCE(msk->allow_infinite_fallback, false); |
ec3edaa7 PK |
1506 | return err; |
1507 | ||
5b950ff4 | 1508 | failed_unlink: |
5b950ff4 | 1509 | list_del(&subflow->node); |
f0715779 | 1510 | sock_put(mptcp_subflow_tcp_sock(subflow)); |
ec3edaa7 | 1511 | |
ec3edaa7 | 1512 | failed: |
e16163b6 | 1513 | subflow->disposable = 1; |
ec3edaa7 PK |
1514 | sock_release(sf); |
1515 | return err; | |
1516 | } | |
1517 | ||
3764b0c5 NR |
1518 | static void mptcp_attach_cgroup(struct sock *parent, struct sock *child) |
1519 | { | |
1520 | #ifdef CONFIG_SOCK_CGROUP_DATA | |
1521 | struct sock_cgroup_data *parent_skcd = &parent->sk_cgrp_data, | |
1522 | *child_skcd = &child->sk_cgrp_data; | |
1523 | ||
1524 | /* only the additional subflows created by kworkers have to be modified */ | |
1525 | if (cgroup_id(sock_cgroup_ptr(parent_skcd)) != | |
1526 | cgroup_id(sock_cgroup_ptr(child_skcd))) { | |
1527 | #ifdef CONFIG_MEMCG | |
1528 | struct mem_cgroup *memcg = parent->sk_memcg; | |
1529 | ||
1530 | mem_cgroup_sk_free(child); | |
1531 | if (memcg && css_tryget(&memcg->css)) | |
1532 | child->sk_memcg = memcg; | |
1533 | #endif /* CONFIG_MEMCG */ | |
1534 | ||
1535 | cgroup_sk_free(child_skcd); | |
1536 | *child_skcd = *parent_skcd; | |
1537 | cgroup_sk_clone(child_skcd); | |
1538 | } | |
1539 | #endif /* CONFIG_SOCK_CGROUP_DATA */ | |
1540 | } | |
1541 | ||
b19bc294 PA |
1542 | static void mptcp_subflow_ops_override(struct sock *ssk) |
1543 | { | |
1544 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1545 | if (ssk->sk_prot == &tcpv6_prot) | |
1546 | ssk->sk_prot = &tcpv6_prot_override; | |
1547 | else | |
1548 | #endif | |
1549 | ssk->sk_prot = &tcp_prot_override; | |
1550 | } | |
1551 | ||
1552 | static void mptcp_subflow_ops_undo_override(struct sock *ssk) | |
1553 | { | |
1554 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) | |
1555 | if (ssk->sk_prot == &tcpv6_prot_override) | |
1556 | ssk->sk_prot = &tcpv6_prot; | |
1557 | else | |
1558 | #endif | |
1559 | ssk->sk_prot = &tcp_prot; | |
1560 | } | |
2303f994 PK |
1561 | int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock) |
1562 | { | |
1563 | struct mptcp_subflow_context *subflow; | |
1564 | struct net *net = sock_net(sk); | |
1565 | struct socket *sf; | |
1566 | int err; | |
1567 | ||
adf73410 PA |
1568 | /* un-accepted server sockets can reach here - on bad configuration |
1569 | * bail early to avoid greater trouble later | |
1570 | */ | |
1571 | if (unlikely(!sk->sk_socket)) | |
1572 | return -EINVAL; | |
1573 | ||
cec37a6e PK |
1574 | err = sock_create_kern(net, sk->sk_family, SOCK_STREAM, IPPROTO_TCP, |
1575 | &sf); | |
2303f994 PK |
1576 | if (err) |
1577 | return err; | |
1578 | ||
1579 | lock_sock(sf->sk); | |
1580 | ||
3764b0c5 NR |
1581 | /* the newly created socket has to be in the same cgroup as its parent */ |
1582 | mptcp_attach_cgroup(sk, sf->sk); | |
1583 | ||
2303f994 PK |
1584 | /* kernel sockets do not by default acquire net ref, but TCP timer |
1585 | * needs it. | |
1586 | */ | |
1587 | sf->sk->sk_net_refcnt = 1; | |
1d2f3d3c | 1588 | get_net_track(net, &sf->sk->ns_tracker, GFP_KERNEL); |
d477eb90 | 1589 | sock_inuse_add(net, 1); |
2303f994 PK |
1590 | err = tcp_set_ulp(sf->sk, "mptcp"); |
1591 | release_sock(sf->sk); | |
1592 | ||
b8ad540d WY |
1593 | if (err) { |
1594 | sock_release(sf); | |
2303f994 | 1595 | return err; |
b8ad540d | 1596 | } |
2303f994 | 1597 | |
7d14b0d2 PA |
1598 | /* the newly created socket really belongs to the owning MPTCP master |
1599 | * socket, even if for additional subflows the allocation is performed | |
1600 | * by a kernel workqueue. Adjust inode references, so that the | |
1601 | * procfs/diag interaces really show this one belonging to the correct | |
1602 | * user. | |
1603 | */ | |
1604 | SOCK_INODE(sf)->i_ino = SOCK_INODE(sk->sk_socket)->i_ino; | |
1605 | SOCK_INODE(sf)->i_uid = SOCK_INODE(sk->sk_socket)->i_uid; | |
1606 | SOCK_INODE(sf)->i_gid = SOCK_INODE(sk->sk_socket)->i_gid; | |
1607 | ||
2303f994 PK |
1608 | subflow = mptcp_subflow_ctx(sf->sk); |
1609 | pr_debug("subflow=%p", subflow); | |
1610 | ||
1611 | *new_sock = sf; | |
79c0949e | 1612 | sock_hold(sk); |
2303f994 | 1613 | subflow->conn = sk; |
b19bc294 | 1614 | mptcp_subflow_ops_override(sf->sk); |
2303f994 PK |
1615 | |
1616 | return 0; | |
1617 | } | |
1618 | ||
1619 | static struct mptcp_subflow_context *subflow_create_ctx(struct sock *sk, | |
1620 | gfp_t priority) | |
1621 | { | |
1622 | struct inet_connection_sock *icsk = inet_csk(sk); | |
1623 | struct mptcp_subflow_context *ctx; | |
1624 | ||
1625 | ctx = kzalloc(sizeof(*ctx), priority); | |
1626 | if (!ctx) | |
1627 | return NULL; | |
1628 | ||
1629 | rcu_assign_pointer(icsk->icsk_ulp_data, ctx); | |
cec37a6e | 1630 | INIT_LIST_HEAD(&ctx->node); |
b19bc294 | 1631 | INIT_LIST_HEAD(&ctx->delegated_node); |
2303f994 PK |
1632 | |
1633 | pr_debug("subflow=%p", ctx); | |
1634 | ||
1635 | ctx->tcp_sock = sk; | |
1636 | ||
1637 | return ctx; | |
1638 | } | |
1639 | ||
648ef4b8 MM |
1640 | static void __subflow_state_change(struct sock *sk) |
1641 | { | |
1642 | struct socket_wq *wq; | |
1643 | ||
1644 | rcu_read_lock(); | |
1645 | wq = rcu_dereference(sk->sk_wq); | |
1646 | if (skwq_has_sleeper(wq)) | |
1647 | wake_up_interruptible_all(&wq->wait); | |
1648 | rcu_read_unlock(); | |
1649 | } | |
1650 | ||
1651 | static bool subflow_is_done(const struct sock *sk) | |
1652 | { | |
1653 | return sk->sk_shutdown & RCV_SHUTDOWN || sk->sk_state == TCP_CLOSE; | |
1654 | } | |
1655 | ||
1656 | static void subflow_state_change(struct sock *sk) | |
1657 | { | |
1658 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); | |
dc093db5 | 1659 | struct sock *parent = subflow->conn; |
648ef4b8 MM |
1660 | |
1661 | __subflow_state_change(sk); | |
1662 | ||
8fd73804 | 1663 | if (subflow_simultaneous_connect(sk)) { |
5cf92bba | 1664 | mptcp_propagate_sndbuf(parent, sk); |
8fd73804 | 1665 | mptcp_do_fallback(sk); |
a6b118fe | 1666 | mptcp_rcv_space_init(mptcp_sk(parent), sk); |
8fd73804 DC |
1667 | pr_fallback(mptcp_sk(parent)); |
1668 | subflow->conn_finished = 1; | |
490274b4 | 1669 | mptcp_set_connected(parent); |
8fd73804 DC |
1670 | } |
1671 | ||
648ef4b8 MM |
1672 | /* as recvmsg() does not acquire the subflow socket for ssk selection |
1673 | * a fin packet carrying a DSS can be unnoticed if we don't trigger | |
1674 | * the data available machinery here. | |
1675 | */ | |
e1ff9e82 | 1676 | if (mptcp_subflow_data_available(sk)) |
2e52213c | 1677 | mptcp_data_ready(parent, sk); |
499ada50 PA |
1678 | else if (unlikely(sk->sk_err)) |
1679 | subflow_error_report(sk); | |
648ef4b8 | 1680 | |
40947e13 FW |
1681 | subflow_sched_work_if_closed(mptcp_sk(parent), sk); |
1682 | ||
067a0b3d | 1683 | if (__mptcp_check_fallback(mptcp_sk(parent)) && |
648ef4b8 MM |
1684 | !subflow->rx_eof && subflow_is_done(sk)) { |
1685 | subflow->rx_eof = 1; | |
59832e24 | 1686 | mptcp_subflow_eof(parent); |
648ef4b8 MM |
1687 | } |
1688 | } | |
1689 | ||
2303f994 PK |
1690 | static int subflow_ulp_init(struct sock *sk) |
1691 | { | |
cec37a6e | 1692 | struct inet_connection_sock *icsk = inet_csk(sk); |
2303f994 PK |
1693 | struct mptcp_subflow_context *ctx; |
1694 | struct tcp_sock *tp = tcp_sk(sk); | |
1695 | int err = 0; | |
1696 | ||
1697 | /* disallow attaching ULP to a socket unless it has been | |
1698 | * created with sock_create_kern() | |
1699 | */ | |
1700 | if (!sk->sk_kern_sock) { | |
1701 | err = -EOPNOTSUPP; | |
1702 | goto out; | |
1703 | } | |
1704 | ||
1705 | ctx = subflow_create_ctx(sk, GFP_KERNEL); | |
1706 | if (!ctx) { | |
1707 | err = -ENOMEM; | |
1708 | goto out; | |
1709 | } | |
1710 | ||
1711 | pr_debug("subflow=%p, family=%d", ctx, sk->sk_family); | |
1712 | ||
1713 | tp->is_mptcp = 1; | |
cec37a6e PK |
1714 | ctx->icsk_af_ops = icsk->icsk_af_ops; |
1715 | icsk->icsk_af_ops = subflow_default_af_ops(sk); | |
648ef4b8 | 1716 | ctx->tcp_state_change = sk->sk_state_change; |
15cc1045 | 1717 | ctx->tcp_error_report = sk->sk_error_report; |
952382c6 FW |
1718 | |
1719 | WARN_ON_ONCE(sk->sk_data_ready != sock_def_readable); | |
1720 | WARN_ON_ONCE(sk->sk_write_space != sk_stream_write_space); | |
1721 | ||
648ef4b8 MM |
1722 | sk->sk_data_ready = subflow_data_ready; |
1723 | sk->sk_write_space = subflow_write_space; | |
1724 | sk->sk_state_change = subflow_state_change; | |
15cc1045 | 1725 | sk->sk_error_report = subflow_error_report; |
2303f994 PK |
1726 | out: |
1727 | return err; | |
1728 | } | |
1729 | ||
e16163b6 | 1730 | static void subflow_ulp_release(struct sock *ssk) |
2303f994 | 1731 | { |
e16163b6 PA |
1732 | struct mptcp_subflow_context *ctx = mptcp_subflow_ctx(ssk); |
1733 | bool release = true; | |
1734 | struct sock *sk; | |
2303f994 PK |
1735 | |
1736 | if (!ctx) | |
1737 | return; | |
1738 | ||
e16163b6 PA |
1739 | sk = ctx->conn; |
1740 | if (sk) { | |
1741 | /* if the msk has been orphaned, keep the ctx | |
0597d0f8 PA |
1742 | * alive, will be freed by __mptcp_close_ssk(), |
1743 | * when the subflow is still unaccepted | |
e16163b6 | 1744 | */ |
0597d0f8 | 1745 | release = ctx->disposable || list_empty(&ctx->node); |
e16163b6 PA |
1746 | sock_put(sk); |
1747 | } | |
79c0949e | 1748 | |
b19bc294 | 1749 | mptcp_subflow_ops_undo_override(ssk); |
e16163b6 PA |
1750 | if (release) |
1751 | kfree_rcu(ctx, rcu); | |
2303f994 PK |
1752 | } |
1753 | ||
cec37a6e PK |
1754 | static void subflow_ulp_clone(const struct request_sock *req, |
1755 | struct sock *newsk, | |
1756 | const gfp_t priority) | |
1757 | { | |
1758 | struct mptcp_subflow_request_sock *subflow_req = mptcp_subflow_rsk(req); | |
1759 | struct mptcp_subflow_context *old_ctx = mptcp_subflow_ctx(newsk); | |
1760 | struct mptcp_subflow_context *new_ctx; | |
1761 | ||
f296234c PK |
1762 | if (!tcp_rsk(req)->is_mptcp || |
1763 | (!subflow_req->mp_capable && !subflow_req->mp_join)) { | |
648ef4b8 | 1764 | subflow_ulp_fallback(newsk, old_ctx); |
cec37a6e PK |
1765 | return; |
1766 | } | |
1767 | ||
1768 | new_ctx = subflow_create_ctx(newsk, priority); | |
edc7e489 | 1769 | if (!new_ctx) { |
648ef4b8 | 1770 | subflow_ulp_fallback(newsk, old_ctx); |
cec37a6e PK |
1771 | return; |
1772 | } | |
1773 | ||
1774 | new_ctx->conn_finished = 1; | |
1775 | new_ctx->icsk_af_ops = old_ctx->icsk_af_ops; | |
648ef4b8 | 1776 | new_ctx->tcp_state_change = old_ctx->tcp_state_change; |
15cc1045 | 1777 | new_ctx->tcp_error_report = old_ctx->tcp_error_report; |
58b09919 PA |
1778 | new_ctx->rel_write_seq = 1; |
1779 | new_ctx->tcp_sock = newsk; | |
1780 | ||
f296234c PK |
1781 | if (subflow_req->mp_capable) { |
1782 | /* see comments in subflow_syn_recv_sock(), MPTCP connection | |
1783 | * is fully established only after we receive the remote key | |
1784 | */ | |
1785 | new_ctx->mp_capable = 1; | |
f296234c PK |
1786 | new_ctx->local_key = subflow_req->local_key; |
1787 | new_ctx->token = subflow_req->token; | |
1788 | new_ctx->ssn_offset = subflow_req->ssn_offset; | |
1789 | new_ctx->idsn = subflow_req->idsn; | |
4cf86ae8 PA |
1790 | |
1791 | /* this is the first subflow, id is always 0 */ | |
1792 | new_ctx->local_id_valid = 1; | |
f296234c | 1793 | } else if (subflow_req->mp_join) { |
ec3edaa7 | 1794 | new_ctx->ssn_offset = subflow_req->ssn_offset; |
f296234c PK |
1795 | new_ctx->mp_join = 1; |
1796 | new_ctx->fully_established = 1; | |
1797 | new_ctx->backup = subflow_req->backup; | |
2ff0e566 | 1798 | new_ctx->remote_id = subflow_req->remote_id; |
f296234c PK |
1799 | new_ctx->token = subflow_req->token; |
1800 | new_ctx->thmac = subflow_req->thmac; | |
4cf86ae8 PA |
1801 | |
1802 | /* the subflow req id is valid, fetched via subflow_check_req() | |
1803 | * and subflow_token_join_request() | |
1804 | */ | |
1805 | subflow_set_local_id(new_ctx, subflow_req->local_id); | |
f296234c | 1806 | } |
cec37a6e PK |
1807 | } |
1808 | ||
b19bc294 PA |
1809 | static void tcp_release_cb_override(struct sock *ssk) |
1810 | { | |
1811 | struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); | |
1812 | ||
1813 | if (mptcp_subflow_has_delegated_action(subflow)) | |
1814 | mptcp_subflow_process_delegated(ssk); | |
1815 | ||
1816 | tcp_release_cb(ssk); | |
1817 | } | |
1818 | ||
2303f994 PK |
1819 | static struct tcp_ulp_ops subflow_ulp_ops __read_mostly = { |
1820 | .name = "mptcp", | |
1821 | .owner = THIS_MODULE, | |
1822 | .init = subflow_ulp_init, | |
1823 | .release = subflow_ulp_release, | |
cec37a6e | 1824 | .clone = subflow_ulp_clone, |
2303f994 PK |
1825 | }; |
1826 | ||
cec37a6e PK |
1827 | static int subflow_ops_init(struct request_sock_ops *subflow_ops) |
1828 | { | |
1829 | subflow_ops->obj_size = sizeof(struct mptcp_subflow_request_sock); | |
1830 | subflow_ops->slab_name = "request_sock_subflow"; | |
1831 | ||
1832 | subflow_ops->slab = kmem_cache_create(subflow_ops->slab_name, | |
1833 | subflow_ops->obj_size, 0, | |
1834 | SLAB_ACCOUNT | | |
1835 | SLAB_TYPESAFE_BY_RCU, | |
1836 | NULL); | |
1837 | if (!subflow_ops->slab) | |
1838 | return -ENOMEM; | |
1839 | ||
79c0949e PK |
1840 | subflow_ops->destructor = subflow_req_destructor; |
1841 | ||
cec37a6e PK |
1842 | return 0; |
1843 | } | |
1844 | ||
d39dceca | 1845 | void __init mptcp_subflow_init(void) |
2303f994 | 1846 | { |
08b8d080 FW |
1847 | mptcp_subflow_request_sock_ops = tcp_request_sock_ops; |
1848 | if (subflow_ops_init(&mptcp_subflow_request_sock_ops) != 0) | |
cec37a6e PK |
1849 | panic("MPTCP: failed to init subflow request sock ops\n"); |
1850 | ||
1851 | subflow_request_sock_ipv4_ops = tcp_request_sock_ipv4_ops; | |
7ea851d1 | 1852 | subflow_request_sock_ipv4_ops.route_req = subflow_v4_route_req; |
cec37a6e PK |
1853 | |
1854 | subflow_specific = ipv4_specific; | |
1855 | subflow_specific.conn_request = subflow_v4_conn_request; | |
1856 | subflow_specific.syn_recv_sock = subflow_syn_recv_sock; | |
1857 | subflow_specific.sk_rx_dst_set = subflow_finish_connect; | |
4cf86ae8 | 1858 | subflow_specific.rebuild_header = subflow_rebuild_header; |
cec37a6e | 1859 | |
b19bc294 PA |
1860 | tcp_prot_override = tcp_prot; |
1861 | tcp_prot_override.release_cb = tcp_release_cb_override; | |
1862 | ||
cec37a6e PK |
1863 | #if IS_ENABLED(CONFIG_MPTCP_IPV6) |
1864 | subflow_request_sock_ipv6_ops = tcp_request_sock_ipv6_ops; | |
7ea851d1 | 1865 | subflow_request_sock_ipv6_ops.route_req = subflow_v6_route_req; |
cec37a6e PK |
1866 | |
1867 | subflow_v6_specific = ipv6_specific; | |
1868 | subflow_v6_specific.conn_request = subflow_v6_conn_request; | |
1869 | subflow_v6_specific.syn_recv_sock = subflow_syn_recv_sock; | |
1870 | subflow_v6_specific.sk_rx_dst_set = subflow_finish_connect; | |
4cf86ae8 | 1871 | subflow_v6_specific.rebuild_header = subflow_v6_rebuild_header; |
cec37a6e PK |
1872 | |
1873 | subflow_v6m_specific = subflow_v6_specific; | |
1874 | subflow_v6m_specific.queue_xmit = ipv4_specific.queue_xmit; | |
1875 | subflow_v6m_specific.send_check = ipv4_specific.send_check; | |
1876 | subflow_v6m_specific.net_header_len = ipv4_specific.net_header_len; | |
1877 | subflow_v6m_specific.mtu_reduced = ipv4_specific.mtu_reduced; | |
1878 | subflow_v6m_specific.net_frag_header_len = 0; | |
4cf86ae8 | 1879 | subflow_v6m_specific.rebuild_header = subflow_rebuild_header; |
b19bc294 PA |
1880 | |
1881 | tcpv6_prot_override = tcpv6_prot; | |
1882 | tcpv6_prot_override.release_cb = tcp_release_cb_override; | |
cec37a6e PK |
1883 | #endif |
1884 | ||
5147dfb5 DC |
1885 | mptcp_diag_subflow_init(&subflow_ulp_ops); |
1886 | ||
2303f994 PK |
1887 | if (tcp_register_ulp(&subflow_ulp_ops) != 0) |
1888 | panic("MPTCP: failed to register subflows to ULP\n"); | |
1889 | } |