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1// SPDX-License-Identifier: GPL-2.0
2/* Multipath TCP
3 *
4 * Copyright (c) 2019, Intel Corporation.
5 */
6#define pr_fmt(fmt) "MPTCP: " fmt
7
8#include <linux/kernel.h>
9#include <net/tcp.h>
10#include <net/mptcp.h>
11#include "protocol.h"
12
13/* path manager command handlers */
14
15int mptcp_pm_announce_addr(struct mptcp_sock *msk,
16 const struct mptcp_addr_info *addr,
17 bool echo)
18{
19 u8 add_addr = READ_ONCE(msk->pm.addr_signal);
20
21 pr_debug("msk=%p, local_id=%d", msk, addr->id);
22
23 lockdep_assert_held(&msk->pm.lock);
24
25 if (add_addr) {
26 pr_warn("addr_signal error, add_addr=%d", add_addr);
27 return -EINVAL;
28 }
29
30 msk->pm.local = *addr;
31 add_addr |= BIT(MPTCP_ADD_ADDR_SIGNAL);
32 if (echo)
33 add_addr |= BIT(MPTCP_ADD_ADDR_ECHO);
34 if (addr->family == AF_INET6)
35 add_addr |= BIT(MPTCP_ADD_ADDR_IPV6);
36 if (addr->port)
37 add_addr |= BIT(MPTCP_ADD_ADDR_PORT);
38 WRITE_ONCE(msk->pm.addr_signal, add_addr);
39 return 0;
40}
41
42int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list)
43{
44 u8 rm_addr = READ_ONCE(msk->pm.addr_signal);
45
46 pr_debug("msk=%p, rm_list_nr=%d", msk, rm_list->nr);
47
48 if (rm_addr) {
49 pr_warn("addr_signal error, rm_addr=%d", rm_addr);
50 return -EINVAL;
51 }
52
53 msk->pm.rm_list_tx = *rm_list;
54 rm_addr |= BIT(MPTCP_RM_ADDR_SIGNAL);
55 WRITE_ONCE(msk->pm.addr_signal, rm_addr);
56 mptcp_pm_nl_addr_send_ack(msk);
57 return 0;
58}
59
60int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list)
61{
62 pr_debug("msk=%p, rm_list_nr=%d", msk, rm_list->nr);
63
64 spin_lock_bh(&msk->pm.lock);
65 mptcp_pm_nl_rm_subflow_received(msk, rm_list);
66 spin_unlock_bh(&msk->pm.lock);
67 return 0;
68}
69
70/* path manager event handlers */
71
72void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side)
73{
74 struct mptcp_pm_data *pm = &msk->pm;
75
76 pr_debug("msk=%p, token=%u side=%d", msk, msk->token, server_side);
77
78 WRITE_ONCE(pm->server_side, server_side);
79 mptcp_event(MPTCP_EVENT_CREATED, msk, ssk, GFP_ATOMIC);
80}
81
82bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
83{
84 struct mptcp_pm_data *pm = &msk->pm;
85 unsigned int subflows_max;
86 int ret = 0;
87
88 subflows_max = mptcp_pm_get_subflows_max(msk);
89
90 pr_debug("msk=%p subflows=%d max=%d allow=%d", msk, pm->subflows,
91 subflows_max, READ_ONCE(pm->accept_subflow));
92
93 /* try to avoid acquiring the lock below */
94 if (!READ_ONCE(pm->accept_subflow))
95 return false;
96
97 spin_lock_bh(&pm->lock);
98 if (READ_ONCE(pm->accept_subflow)) {
99 ret = pm->subflows < subflows_max;
100 if (ret && ++pm->subflows == subflows_max)
101 WRITE_ONCE(pm->accept_subflow, false);
102 }
103 spin_unlock_bh(&pm->lock);
104
105 return ret;
106}
107
108/* return true if the new status bit is currently cleared, that is, this event
109 * can be server, eventually by an already scheduled work
110 */
111static bool mptcp_pm_schedule_work(struct mptcp_sock *msk,
112 enum mptcp_pm_status new_status)
113{
114 pr_debug("msk=%p status=%x new=%lx", msk, msk->pm.status,
115 BIT(new_status));
116 if (msk->pm.status & BIT(new_status))
117 return false;
118
119 msk->pm.status |= BIT(new_status);
120 mptcp_schedule_work((struct sock *)msk);
121 return true;
122}
123
124void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp)
125{
126 struct mptcp_pm_data *pm = &msk->pm;
127 bool announce = false;
128
129 pr_debug("msk=%p", msk);
130
131 spin_lock_bh(&pm->lock);
132
133 /* mptcp_pm_fully_established() can be invoked by multiple
134 * racing paths - accept() and check_fully_established()
135 * be sure to serve this event only once.
136 */
137 if (READ_ONCE(pm->work_pending) &&
138 !(msk->pm.status & BIT(MPTCP_PM_ALREADY_ESTABLISHED)))
139 mptcp_pm_schedule_work(msk, MPTCP_PM_ESTABLISHED);
140
141 if ((msk->pm.status & BIT(MPTCP_PM_ALREADY_ESTABLISHED)) == 0)
142 announce = true;
143
144 msk->pm.status |= BIT(MPTCP_PM_ALREADY_ESTABLISHED);
145 spin_unlock_bh(&pm->lock);
146
147 if (announce)
148 mptcp_event(MPTCP_EVENT_ESTABLISHED, msk, ssk, gfp);
149}
150
151void mptcp_pm_connection_closed(struct mptcp_sock *msk)
152{
153 pr_debug("msk=%p", msk);
154}
155
156void mptcp_pm_subflow_established(struct mptcp_sock *msk)
157{
158 struct mptcp_pm_data *pm = &msk->pm;
159
160 pr_debug("msk=%p", msk);
161
162 if (!READ_ONCE(pm->work_pending))
163 return;
164
165 spin_lock_bh(&pm->lock);
166
167 if (READ_ONCE(pm->work_pending))
168 mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
169
170 spin_unlock_bh(&pm->lock);
171}
172
173void mptcp_pm_subflow_closed(struct mptcp_sock *msk, u8 id)
174{
175 pr_debug("msk=%p", msk);
176}
177
178void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
179 const struct mptcp_addr_info *addr)
180{
181 struct mptcp_pm_data *pm = &msk->pm;
182
183 pr_debug("msk=%p remote_id=%d accept=%d", msk, addr->id,
184 READ_ONCE(pm->accept_addr));
185
186 mptcp_event_addr_announced(msk, addr);
187
188 spin_lock_bh(&pm->lock);
189
190 if (!READ_ONCE(pm->accept_addr)) {
191 mptcp_pm_announce_addr(msk, addr, true);
192 mptcp_pm_add_addr_send_ack(msk);
193 } else if (mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED)) {
194 pm->remote = *addr;
195 }
196
197 spin_unlock_bh(&pm->lock);
198}
199
200void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
201 struct mptcp_addr_info *addr)
202{
203 struct mptcp_pm_data *pm = &msk->pm;
204
205 pr_debug("msk=%p", msk);
206
207 spin_lock_bh(&pm->lock);
208
209 if (mptcp_lookup_anno_list_by_saddr(msk, addr) && READ_ONCE(pm->work_pending))
210 mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
211
212 spin_unlock_bh(&pm->lock);
213}
214
215void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk)
216{
217 if (!mptcp_pm_should_add_signal(msk))
218 return;
219
220 mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_SEND_ACK);
221}
222
223void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
224 const struct mptcp_rm_list *rm_list)
225{
226 struct mptcp_pm_data *pm = &msk->pm;
227 u8 i;
228
229 pr_debug("msk=%p remote_ids_nr=%d", msk, rm_list->nr);
230
231 for (i = 0; i < rm_list->nr; i++)
232 mptcp_event_addr_removed(msk, rm_list->ids[i]);
233
234 spin_lock_bh(&pm->lock);
235 mptcp_pm_schedule_work(msk, MPTCP_PM_RM_ADDR_RECEIVED);
236 pm->rm_list_rx = *rm_list;
237 spin_unlock_bh(&pm->lock);
238}
239
240void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup)
241{
242 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
243
244 pr_debug("subflow->backup=%d, bkup=%d\n", subflow->backup, bkup);
245 subflow->backup = bkup;
246
247 mptcp_event(MPTCP_EVENT_SUB_PRIORITY, mptcp_sk(subflow->conn), sk, GFP_ATOMIC);
248}
249
250/* path manager helpers */
251
252bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
253 struct mptcp_addr_info *saddr, bool *echo, bool *port)
254{
255 int ret = false;
256
257 spin_lock_bh(&msk->pm.lock);
258
259 /* double check after the lock is acquired */
260 if (!mptcp_pm_should_add_signal(msk))
261 goto out_unlock;
262
263 *echo = mptcp_pm_should_add_signal_echo(msk);
264 *port = mptcp_pm_should_add_signal_port(msk);
265
266 if (remaining < mptcp_add_addr_len(msk->pm.local.family, *echo, *port))
267 goto out_unlock;
268
269 *saddr = msk->pm.local;
270 WRITE_ONCE(msk->pm.addr_signal, 0);
271 ret = true;
272
273out_unlock:
274 spin_unlock_bh(&msk->pm.lock);
275 return ret;
276}
277
278bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
279 struct mptcp_rm_list *rm_list)
280{
281 int ret = false, len;
282
283 spin_lock_bh(&msk->pm.lock);
284
285 /* double check after the lock is acquired */
286 if (!mptcp_pm_should_rm_signal(msk))
287 goto out_unlock;
288
289 len = mptcp_rm_addr_len(&msk->pm.rm_list_tx);
290 if (len < 0) {
291 WRITE_ONCE(msk->pm.addr_signal, 0);
292 goto out_unlock;
293 }
294 if (remaining < len)
295 goto out_unlock;
296
297 *rm_list = msk->pm.rm_list_tx;
298 WRITE_ONCE(msk->pm.addr_signal, 0);
299 ret = true;
300
301out_unlock:
302 spin_unlock_bh(&msk->pm.lock);
303 return ret;
304}
305
306int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
307{
308 return mptcp_pm_nl_get_local_id(msk, skc);
309}
310
311void mptcp_pm_data_init(struct mptcp_sock *msk)
312{
313 msk->pm.add_addr_signaled = 0;
314 msk->pm.add_addr_accepted = 0;
315 msk->pm.local_addr_used = 0;
316 msk->pm.subflows = 0;
317 msk->pm.rm_list_tx.nr = 0;
318 msk->pm.rm_list_rx.nr = 0;
319 WRITE_ONCE(msk->pm.work_pending, false);
320 WRITE_ONCE(msk->pm.addr_signal, 0);
321 WRITE_ONCE(msk->pm.accept_addr, false);
322 WRITE_ONCE(msk->pm.accept_subflow, false);
323 WRITE_ONCE(msk->pm.remote_deny_join_id0, false);
324 msk->pm.status = 0;
325
326 spin_lock_init(&msk->pm.lock);
327 INIT_LIST_HEAD(&msk->pm.anno_list);
328
329 mptcp_pm_nl_data_init(msk);
330}
331
332void __init mptcp_pm_init(void)
333{
334 mptcp_pm_nl_init();
335}
1// SPDX-License-Identifier: GPL-2.0
2/* Multipath TCP
3 *
4 * Copyright (c) 2019, Intel Corporation.
5 */
6#define pr_fmt(fmt) "MPTCP: " fmt
7
8#include <linux/kernel.h>
9#include <net/mptcp.h>
10#include "protocol.h"
11
12#include "mib.h"
13
14/* path manager command handlers */
15
16int mptcp_pm_announce_addr(struct mptcp_sock *msk,
17 const struct mptcp_addr_info *addr,
18 bool echo)
19{
20 u8 add_addr = READ_ONCE(msk->pm.addr_signal);
21
22 pr_debug("msk=%p, local_id=%d, echo=%d\n", msk, addr->id, echo);
23
24 lockdep_assert_held(&msk->pm.lock);
25
26 if (add_addr &
27 (echo ? BIT(MPTCP_ADD_ADDR_ECHO) : BIT(MPTCP_ADD_ADDR_SIGNAL))) {
28 MPTCP_INC_STATS(sock_net((struct sock *)msk),
29 echo ? MPTCP_MIB_ECHOADDTXDROP : MPTCP_MIB_ADDADDRTXDROP);
30 return -EINVAL;
31 }
32
33 if (echo) {
34 msk->pm.remote = *addr;
35 add_addr |= BIT(MPTCP_ADD_ADDR_ECHO);
36 } else {
37 msk->pm.local = *addr;
38 add_addr |= BIT(MPTCP_ADD_ADDR_SIGNAL);
39 }
40 WRITE_ONCE(msk->pm.addr_signal, add_addr);
41 return 0;
42}
43
44int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list)
45{
46 u8 rm_addr = READ_ONCE(msk->pm.addr_signal);
47
48 pr_debug("msk=%p, rm_list_nr=%d\n", msk, rm_list->nr);
49
50 if (rm_addr) {
51 MPTCP_ADD_STATS(sock_net((struct sock *)msk),
52 MPTCP_MIB_RMADDRTXDROP, rm_list->nr);
53 return -EINVAL;
54 }
55
56 msk->pm.rm_list_tx = *rm_list;
57 rm_addr |= BIT(MPTCP_RM_ADDR_SIGNAL);
58 WRITE_ONCE(msk->pm.addr_signal, rm_addr);
59 mptcp_pm_nl_addr_send_ack(msk);
60 return 0;
61}
62
63/* path manager event handlers */
64
65void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side)
66{
67 struct mptcp_pm_data *pm = &msk->pm;
68
69 pr_debug("msk=%p, token=%u side=%d\n", msk, READ_ONCE(msk->token), server_side);
70
71 WRITE_ONCE(pm->server_side, server_side);
72 mptcp_event(MPTCP_EVENT_CREATED, msk, ssk, GFP_ATOMIC);
73}
74
75bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
76{
77 struct mptcp_pm_data *pm = &msk->pm;
78 unsigned int subflows_max;
79 int ret = 0;
80
81 if (mptcp_pm_is_userspace(msk)) {
82 if (mptcp_userspace_pm_active(msk)) {
83 spin_lock_bh(&pm->lock);
84 pm->subflows++;
85 spin_unlock_bh(&pm->lock);
86 return true;
87 }
88 return false;
89 }
90
91 subflows_max = mptcp_pm_get_subflows_max(msk);
92
93 pr_debug("msk=%p subflows=%d max=%d allow=%d\n", msk, pm->subflows,
94 subflows_max, READ_ONCE(pm->accept_subflow));
95
96 /* try to avoid acquiring the lock below */
97 if (!READ_ONCE(pm->accept_subflow))
98 return false;
99
100 spin_lock_bh(&pm->lock);
101 if (READ_ONCE(pm->accept_subflow)) {
102 ret = pm->subflows < subflows_max;
103 if (ret && ++pm->subflows == subflows_max)
104 WRITE_ONCE(pm->accept_subflow, false);
105 }
106 spin_unlock_bh(&pm->lock);
107
108 return ret;
109}
110
111/* return true if the new status bit is currently cleared, that is, this event
112 * can be server, eventually by an already scheduled work
113 */
114static bool mptcp_pm_schedule_work(struct mptcp_sock *msk,
115 enum mptcp_pm_status new_status)
116{
117 pr_debug("msk=%p status=%x new=%lx\n", msk, msk->pm.status,
118 BIT(new_status));
119 if (msk->pm.status & BIT(new_status))
120 return false;
121
122 msk->pm.status |= BIT(new_status);
123 mptcp_schedule_work((struct sock *)msk);
124 return true;
125}
126
127void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk)
128{
129 struct mptcp_pm_data *pm = &msk->pm;
130 bool announce = false;
131
132 pr_debug("msk=%p\n", msk);
133
134 spin_lock_bh(&pm->lock);
135
136 /* mptcp_pm_fully_established() can be invoked by multiple
137 * racing paths - accept() and check_fully_established()
138 * be sure to serve this event only once.
139 */
140 if (READ_ONCE(pm->work_pending) &&
141 !(msk->pm.status & BIT(MPTCP_PM_ALREADY_ESTABLISHED)))
142 mptcp_pm_schedule_work(msk, MPTCP_PM_ESTABLISHED);
143
144 if ((msk->pm.status & BIT(MPTCP_PM_ALREADY_ESTABLISHED)) == 0)
145 announce = true;
146
147 msk->pm.status |= BIT(MPTCP_PM_ALREADY_ESTABLISHED);
148 spin_unlock_bh(&pm->lock);
149
150 if (announce)
151 mptcp_event(MPTCP_EVENT_ESTABLISHED, msk, ssk, GFP_ATOMIC);
152}
153
154void mptcp_pm_connection_closed(struct mptcp_sock *msk)
155{
156 pr_debug("msk=%p\n", msk);
157
158 if (msk->token)
159 mptcp_event(MPTCP_EVENT_CLOSED, msk, NULL, GFP_KERNEL);
160}
161
162void mptcp_pm_subflow_established(struct mptcp_sock *msk)
163{
164 struct mptcp_pm_data *pm = &msk->pm;
165
166 pr_debug("msk=%p\n", msk);
167
168 if (!READ_ONCE(pm->work_pending))
169 return;
170
171 spin_lock_bh(&pm->lock);
172
173 if (READ_ONCE(pm->work_pending))
174 mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
175
176 spin_unlock_bh(&pm->lock);
177}
178
179void mptcp_pm_subflow_check_next(struct mptcp_sock *msk,
180 const struct mptcp_subflow_context *subflow)
181{
182 struct mptcp_pm_data *pm = &msk->pm;
183 bool update_subflows;
184
185 update_subflows = subflow->request_join || subflow->mp_join;
186 if (mptcp_pm_is_userspace(msk)) {
187 if (update_subflows) {
188 spin_lock_bh(&pm->lock);
189 pm->subflows--;
190 spin_unlock_bh(&pm->lock);
191 }
192 return;
193 }
194
195 if (!READ_ONCE(pm->work_pending) && !update_subflows)
196 return;
197
198 spin_lock_bh(&pm->lock);
199 if (update_subflows)
200 __mptcp_pm_close_subflow(msk);
201
202 /* Even if this subflow is not really established, tell the PM to try
203 * to pick the next ones, if possible.
204 */
205 if (mptcp_pm_nl_check_work_pending(msk))
206 mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
207
208 spin_unlock_bh(&pm->lock);
209}
210
211void mptcp_pm_add_addr_received(const struct sock *ssk,
212 const struct mptcp_addr_info *addr)
213{
214 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
215 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
216 struct mptcp_pm_data *pm = &msk->pm;
217
218 pr_debug("msk=%p remote_id=%d accept=%d\n", msk, addr->id,
219 READ_ONCE(pm->accept_addr));
220
221 mptcp_event_addr_announced(ssk, addr);
222
223 spin_lock_bh(&pm->lock);
224
225 if (mptcp_pm_is_userspace(msk)) {
226 if (mptcp_userspace_pm_active(msk)) {
227 mptcp_pm_announce_addr(msk, addr, true);
228 mptcp_pm_add_addr_send_ack(msk);
229 } else {
230 __MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_ADDADDRDROP);
231 }
232 /* id0 should not have a different address */
233 } else if ((addr->id == 0 && !mptcp_pm_nl_is_init_remote_addr(msk, addr)) ||
234 (addr->id > 0 && !READ_ONCE(pm->accept_addr))) {
235 mptcp_pm_announce_addr(msk, addr, true);
236 mptcp_pm_add_addr_send_ack(msk);
237 } else if (mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED)) {
238 pm->remote = *addr;
239 } else {
240 __MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_ADDADDRDROP);
241 }
242
243 spin_unlock_bh(&pm->lock);
244}
245
246void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk,
247 const struct mptcp_addr_info *addr)
248{
249 struct mptcp_pm_data *pm = &msk->pm;
250
251 pr_debug("msk=%p\n", msk);
252
253 spin_lock_bh(&pm->lock);
254
255 if (mptcp_lookup_anno_list_by_saddr(msk, addr) && READ_ONCE(pm->work_pending))
256 mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
257
258 spin_unlock_bh(&pm->lock);
259}
260
261void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk)
262{
263 if (!mptcp_pm_should_add_signal(msk))
264 return;
265
266 mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_SEND_ACK);
267}
268
269void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
270 const struct mptcp_rm_list *rm_list)
271{
272 struct mptcp_pm_data *pm = &msk->pm;
273 u8 i;
274
275 pr_debug("msk=%p remote_ids_nr=%d\n", msk, rm_list->nr);
276
277 for (i = 0; i < rm_list->nr; i++)
278 mptcp_event_addr_removed(msk, rm_list->ids[i]);
279
280 spin_lock_bh(&pm->lock);
281 if (mptcp_pm_schedule_work(msk, MPTCP_PM_RM_ADDR_RECEIVED))
282 pm->rm_list_rx = *rm_list;
283 else
284 __MPTCP_INC_STATS(sock_net((struct sock *)msk), MPTCP_MIB_RMADDRDROP);
285 spin_unlock_bh(&pm->lock);
286}
287
288void mptcp_pm_mp_prio_received(struct sock *ssk, u8 bkup)
289{
290 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
291 struct sock *sk = subflow->conn;
292 struct mptcp_sock *msk;
293
294 pr_debug("subflow->backup=%d, bkup=%d\n", subflow->backup, bkup);
295 msk = mptcp_sk(sk);
296 if (subflow->backup != bkup)
297 subflow->backup = bkup;
298
299 mptcp_event(MPTCP_EVENT_SUB_PRIORITY, msk, ssk, GFP_ATOMIC);
300}
301
302void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq)
303{
304 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
305 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
306
307 pr_debug("fail_seq=%llu\n", fail_seq);
308
309 if (!READ_ONCE(msk->allow_infinite_fallback))
310 return;
311
312 if (!subflow->fail_tout) {
313 pr_debug("send MP_FAIL response and infinite map\n");
314
315 subflow->send_mp_fail = 1;
316 subflow->send_infinite_map = 1;
317 tcp_send_ack(sk);
318 } else {
319 pr_debug("MP_FAIL response received\n");
320 WRITE_ONCE(subflow->fail_tout, 0);
321 }
322}
323
324/* path manager helpers */
325
326bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
327 unsigned int opt_size, unsigned int remaining,
328 struct mptcp_addr_info *addr, bool *echo,
329 bool *drop_other_suboptions)
330{
331 int ret = false;
332 u8 add_addr;
333 u8 family;
334 bool port;
335
336 spin_lock_bh(&msk->pm.lock);
337
338 /* double check after the lock is acquired */
339 if (!mptcp_pm_should_add_signal(msk))
340 goto out_unlock;
341
342 /* always drop every other options for pure ack ADD_ADDR; this is a
343 * plain dup-ack from TCP perspective. The other MPTCP-relevant info,
344 * if any, will be carried by the 'original' TCP ack
345 */
346 if (skb && skb_is_tcp_pure_ack(skb)) {
347 remaining += opt_size;
348 *drop_other_suboptions = true;
349 }
350
351 *echo = mptcp_pm_should_add_signal_echo(msk);
352 port = !!(*echo ? msk->pm.remote.port : msk->pm.local.port);
353
354 family = *echo ? msk->pm.remote.family : msk->pm.local.family;
355 if (remaining < mptcp_add_addr_len(family, *echo, port))
356 goto out_unlock;
357
358 if (*echo) {
359 *addr = msk->pm.remote;
360 add_addr = msk->pm.addr_signal & ~BIT(MPTCP_ADD_ADDR_ECHO);
361 } else {
362 *addr = msk->pm.local;
363 add_addr = msk->pm.addr_signal & ~BIT(MPTCP_ADD_ADDR_SIGNAL);
364 }
365 WRITE_ONCE(msk->pm.addr_signal, add_addr);
366 ret = true;
367
368out_unlock:
369 spin_unlock_bh(&msk->pm.lock);
370 return ret;
371}
372
373bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
374 struct mptcp_rm_list *rm_list)
375{
376 int ret = false, len;
377 u8 rm_addr;
378
379 spin_lock_bh(&msk->pm.lock);
380
381 /* double check after the lock is acquired */
382 if (!mptcp_pm_should_rm_signal(msk))
383 goto out_unlock;
384
385 rm_addr = msk->pm.addr_signal & ~BIT(MPTCP_RM_ADDR_SIGNAL);
386 len = mptcp_rm_addr_len(&msk->pm.rm_list_tx);
387 if (len < 0) {
388 WRITE_ONCE(msk->pm.addr_signal, rm_addr);
389 goto out_unlock;
390 }
391 if (remaining < len)
392 goto out_unlock;
393
394 *rm_list = msk->pm.rm_list_tx;
395 WRITE_ONCE(msk->pm.addr_signal, rm_addr);
396 ret = true;
397
398out_unlock:
399 spin_unlock_bh(&msk->pm.lock);
400 return ret;
401}
402
403int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
404{
405 struct mptcp_addr_info skc_local;
406 struct mptcp_addr_info msk_local;
407
408 if (WARN_ON_ONCE(!msk))
409 return -1;
410
411 /* The 0 ID mapping is defined by the first subflow, copied into the msk
412 * addr
413 */
414 mptcp_local_address((struct sock_common *)msk, &msk_local);
415 mptcp_local_address((struct sock_common *)skc, &skc_local);
416 if (mptcp_addresses_equal(&msk_local, &skc_local, false))
417 return 0;
418
419 if (mptcp_pm_is_userspace(msk))
420 return mptcp_userspace_pm_get_local_id(msk, &skc_local);
421 return mptcp_pm_nl_get_local_id(msk, &skc_local);
422}
423
424bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc)
425{
426 struct mptcp_addr_info skc_local;
427
428 mptcp_local_address((struct sock_common *)skc, &skc_local);
429
430 if (mptcp_pm_is_userspace(msk))
431 return mptcp_userspace_pm_is_backup(msk, &skc_local);
432
433 return mptcp_pm_nl_is_backup(msk, &skc_local);
434}
435
436int mptcp_pm_get_addr(struct sk_buff *skb, struct genl_info *info)
437{
438 if (info->attrs[MPTCP_PM_ATTR_TOKEN])
439 return mptcp_userspace_pm_get_addr(skb, info);
440 return mptcp_pm_nl_get_addr(skb, info);
441}
442
443int mptcp_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb)
444{
445 const struct genl_info *info = genl_info_dump(cb);
446
447 if (info->attrs[MPTCP_PM_ATTR_TOKEN])
448 return mptcp_userspace_pm_dump_addr(msg, cb);
449 return mptcp_pm_nl_dump_addr(msg, cb);
450}
451
452int mptcp_pm_set_flags(struct sk_buff *skb, struct genl_info *info)
453{
454 if (info->attrs[MPTCP_PM_ATTR_TOKEN])
455 return mptcp_userspace_pm_set_flags(skb, info);
456 return mptcp_pm_nl_set_flags(skb, info);
457}
458
459void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk)
460{
461 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
462 u32 rcv_tstamp = READ_ONCE(tcp_sk(ssk)->rcv_tstamp);
463
464 /* keep track of rtx periods with no progress */
465 if (!subflow->stale_count) {
466 subflow->stale_rcv_tstamp = rcv_tstamp;
467 subflow->stale_count++;
468 } else if (subflow->stale_rcv_tstamp == rcv_tstamp) {
469 if (subflow->stale_count < U8_MAX)
470 subflow->stale_count++;
471 mptcp_pm_nl_subflow_chk_stale(msk, ssk);
472 } else {
473 subflow->stale_count = 0;
474 mptcp_subflow_set_active(subflow);
475 }
476}
477
478/* if sk is ipv4 or ipv6_only allows only same-family local and remote addresses,
479 * otherwise allow any matching local/remote pair
480 */
481bool mptcp_pm_addr_families_match(const struct sock *sk,
482 const struct mptcp_addr_info *loc,
483 const struct mptcp_addr_info *rem)
484{
485 bool mptcp_is_v4 = sk->sk_family == AF_INET;
486
487#if IS_ENABLED(CONFIG_MPTCP_IPV6)
488 bool loc_is_v4 = loc->family == AF_INET || ipv6_addr_v4mapped(&loc->addr6);
489 bool rem_is_v4 = rem->family == AF_INET || ipv6_addr_v4mapped(&rem->addr6);
490
491 if (mptcp_is_v4)
492 return loc_is_v4 && rem_is_v4;
493
494 if (ipv6_only_sock(sk))
495 return !loc_is_v4 && !rem_is_v4;
496
497 return loc_is_v4 == rem_is_v4;
498#else
499 return mptcp_is_v4 && loc->family == AF_INET && rem->family == AF_INET;
500#endif
501}
502
503void mptcp_pm_data_reset(struct mptcp_sock *msk)
504{
505 u8 pm_type = mptcp_get_pm_type(sock_net((struct sock *)msk));
506 struct mptcp_pm_data *pm = &msk->pm;
507
508 pm->add_addr_signaled = 0;
509 pm->add_addr_accepted = 0;
510 pm->local_addr_used = 0;
511 pm->subflows = 0;
512 pm->rm_list_tx.nr = 0;
513 pm->rm_list_rx.nr = 0;
514 WRITE_ONCE(pm->pm_type, pm_type);
515
516 if (pm_type == MPTCP_PM_TYPE_KERNEL) {
517 bool subflows_allowed = !!mptcp_pm_get_subflows_max(msk);
518
519 /* pm->work_pending must be only be set to 'true' when
520 * pm->pm_type is set to MPTCP_PM_TYPE_KERNEL
521 */
522 WRITE_ONCE(pm->work_pending,
523 (!!mptcp_pm_get_local_addr_max(msk) &&
524 subflows_allowed) ||
525 !!mptcp_pm_get_add_addr_signal_max(msk));
526 WRITE_ONCE(pm->accept_addr,
527 !!mptcp_pm_get_add_addr_accept_max(msk) &&
528 subflows_allowed);
529 WRITE_ONCE(pm->accept_subflow, subflows_allowed);
530 } else {
531 WRITE_ONCE(pm->work_pending, 0);
532 WRITE_ONCE(pm->accept_addr, 0);
533 WRITE_ONCE(pm->accept_subflow, 0);
534 }
535
536 WRITE_ONCE(pm->addr_signal, 0);
537 WRITE_ONCE(pm->remote_deny_join_id0, false);
538 pm->status = 0;
539 bitmap_fill(msk->pm.id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
540}
541
542void mptcp_pm_data_init(struct mptcp_sock *msk)
543{
544 spin_lock_init(&msk->pm.lock);
545 INIT_LIST_HEAD(&msk->pm.anno_list);
546 INIT_LIST_HEAD(&msk->pm.userspace_pm_local_addr_list);
547 mptcp_pm_data_reset(msk);
548}
549
550void __init mptcp_pm_init(void)
551{
552 mptcp_pm_nl_init();
553}