1 | /* |
2 | * Copyright (c) 2012-2017 Apple Inc. All rights reserved. |
3 | * |
4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
5 | * |
6 | * This file contains Original Code and/or Modifications of Original Code |
7 | * as defined in and that are subject to the Apple Public Source License |
8 | * Version 2.0 (the 'License'). You may not use this file except in |
9 | * compliance with the License. The rights granted to you under the License |
10 | * may not be used to create, or enable the creation or redistribution of, |
11 | * unlawful or unlicensed copies of an Apple operating system, or to |
12 | * circumvent, violate, or enable the circumvention or violation of, any |
13 | * terms of an Apple operating system software license agreement. |
14 | * |
15 | * Please obtain a copy of the License at |
16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
17 | * |
18 | * The Original Code and all software distributed under the License are |
19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
23 | * Please see the License for the specific language governing rights and |
24 | * limitations under the License. |
25 | * |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | |
29 | #include <sys/param.h> |
30 | #include <sys/systm.h> |
31 | #include <sys/kernel.h> |
32 | #include <sys/mcache.h> |
33 | #include <sys/socket.h> |
34 | #include <sys/socketvar.h> |
35 | #include <sys/syslog.h> |
36 | #include <sys/protosw.h> |
37 | #include <sys/sysctl.h> |
38 | |
39 | #include <mach/sdt.h> |
40 | |
41 | #include <netinet/mp_pcb.h> |
42 | #include <netinet/mptcp_var.h> |
43 | #include <netinet/mptcp_timer.h> |
44 | #include <netinet/mptcp_seq.h> |
45 | |
46 | #include <kern/locks.h> |
47 | |
48 | /* |
49 | * MPTCP Retransmission Timer comes into play only when subflow level |
50 | * data is acked, but Data ACK is not received. Time is in seconds. |
51 | */ |
52 | static u_int32_t mptcp_rto = 3; |
53 | SYSCTL_INT(_net_inet_mptcp, OID_AUTO, rto, CTLFLAG_RW | CTLFLAG_LOCKED, |
54 | &mptcp_rto, 0, "MPTCP Retransmission Timeout" ); |
55 | |
56 | static int mptcp_nrtos = 3; |
57 | SYSCTL_INT(_net_inet_mptcp, OID_AUTO, nrto, CTLFLAG_RW | CTLFLAG_LOCKED, |
58 | &mptcp_rto, 0, "MPTCP Retransmissions" ); |
59 | |
60 | /* |
61 | * MPTCP connections timewait interval in seconds. |
62 | */ |
63 | static u_int32_t mptcp_tw = 60; |
64 | SYSCTL_INT(_net_inet_mptcp, OID_AUTO, tw, CTLFLAG_RW | CTLFLAG_LOCKED, |
65 | &mptcp_tw, 0, "MPTCP Timewait Period" ); |
66 | |
67 | #define TIMEVAL_TO_HZ(_tv_) ((_tv_).tv_sec * hz + (_tv_).tv_usec / hz) |
68 | |
69 | static int mptcp_cancel_urgency_timer(struct mptses *mpte); |
70 | |
71 | static int |
72 | mptcp_timer_demux(struct mptses *mpte, uint64_t now_msecs) |
73 | { |
74 | struct mptcb *mp_tp = NULL; |
75 | mp_tp = mpte->mpte_mptcb; |
76 | int resched_timer = 0; |
77 | |
78 | DTRACE_MPTCP2(timer, struct mptses *, mpte, struct mptcb *, mp_tp); |
79 | |
80 | switch (mp_tp->mpt_timer_vals) { |
81 | case MPTT_REXMT: |
82 | if (mp_tp->mpt_rxtstart == 0) { |
83 | break; |
84 | } |
85 | if ((now_msecs - mp_tp->mpt_rxtstart) > (mptcp_rto * hz)) { |
86 | if (MPTCP_SEQ_GT(mp_tp->mpt_snduna, mp_tp->mpt_rtseq)) { |
87 | mp_tp->mpt_timer_vals = 0; |
88 | mp_tp->mpt_rtseq = 0; |
89 | break; |
90 | } |
91 | mp_tp->mpt_rxtshift++; |
92 | if (mp_tp->mpt_rxtshift > mptcp_nrtos) { |
93 | mp_tp->mpt_softerror = ETIMEDOUT; |
94 | DTRACE_MPTCP1(error, struct mptcb *, mp_tp); |
95 | } else { |
96 | mp_tp->mpt_sndnxt = mp_tp->mpt_rtseq; |
97 | os_log_info(mptcp_log_handle, |
98 | "%s: REXMT %d sndnxt %u\n" , |
99 | __func__, mp_tp->mpt_rxtshift, |
100 | (uint32_t)mp_tp->mpt_sndnxt); |
101 | mptcp_output(mpte); |
102 | } |
103 | } else { |
104 | resched_timer = 1; |
105 | } |
106 | break; |
107 | case MPTT_TW: |
108 | /* Allows for break before make XXX */ |
109 | if (mp_tp->mpt_timewait == 0) { |
110 | VERIFY(0); |
111 | } |
112 | if ((now_msecs - mp_tp->mpt_timewait) > |
113 | (mptcp_tw * hz)) { |
114 | mp_tp->mpt_softerror = ETIMEDOUT; |
115 | DTRACE_MPTCP1(error, struct mptcb *, mp_tp); |
116 | } else { |
117 | resched_timer = 1; |
118 | } |
119 | break; |
120 | case MPTT_FASTCLOSE: |
121 | /* TODO XXX */ |
122 | break; |
123 | default: |
124 | break; |
125 | } |
126 | |
127 | return resched_timer; |
128 | } |
129 | |
130 | uint32_t |
131 | mptcp_timer(struct mppcbinfo *mppi) |
132 | { |
133 | struct mppcb *mpp, *tmpp; |
134 | struct timeval now; |
135 | uint32_t resched_timer = 0; |
136 | uint64_t now_msecs; |
137 | |
138 | LCK_MTX_ASSERT(&mppi->mppi_lock, LCK_MTX_ASSERT_OWNED); |
139 | |
140 | microuptime(tv: &now); |
141 | now_msecs = TIMEVAL_TO_HZ(now); |
142 | TAILQ_FOREACH_SAFE(mpp, &mppi->mppi_pcbs, mpp_entry, tmpp) { |
143 | struct socket *mp_so; |
144 | struct mptses *mpte; |
145 | |
146 | mp_so = mpp->mpp_socket; |
147 | mpte = mptompte(mp: mpp); |
148 | socket_lock(so: mp_so, refcount: 1); |
149 | |
150 | VERIFY(mpp->mpp_flags & MPP_ATTACHED); |
151 | |
152 | if (mptcp_timer_demux(mpte, now_msecs)) { |
153 | resched_timer = 1; |
154 | } |
155 | socket_unlock(so: mp_so, refcount: 1); |
156 | } |
157 | |
158 | return resched_timer; |
159 | } |
160 | |
161 | void |
162 | mptcp_start_timer(struct mptses *mpte, int timer_type) |
163 | { |
164 | struct timeval now; |
165 | struct mptcb *mp_tp = mpte->mpte_mptcb; |
166 | |
167 | microuptime(tv: &now); |
168 | |
169 | DTRACE_MPTCP2(start__timer, struct mptcb *, mp_tp, int, timer_type); |
170 | |
171 | socket_lock_assert_owned(so: mptetoso(mpte)); |
172 | |
173 | switch (timer_type) { |
174 | case MPTT_REXMT: |
175 | mp_tp->mpt_timer_vals |= MPTT_REXMT; |
176 | mp_tp->mpt_rxtstart = TIMEVAL_TO_HZ(now); |
177 | mp_tp->mpt_rxtshift = 0; |
178 | mp_tp->mpt_rtseq = mp_tp->mpt_sndnxt; |
179 | break; |
180 | case MPTT_TW: |
181 | /* XXX: Not implemented yet */ |
182 | mp_tp->mpt_timer_vals |= MPTT_TW; |
183 | mp_tp->mpt_timewait = TIMEVAL_TO_HZ(now); |
184 | break; |
185 | case MPTT_FASTCLOSE: |
186 | /* NO-OP */ |
187 | break; |
188 | default: |
189 | VERIFY(0); |
190 | /* NOTREACHED */ |
191 | } |
192 | mptcp_timer_sched(); |
193 | } |
194 | |
195 | void |
196 | mptcp_cancel_timer(struct mptcb *mp_tp, int timer_type) |
197 | { |
198 | socket_lock_assert_owned(so: mptetoso(mpte: mp_tp->mpt_mpte)); |
199 | |
200 | switch (timer_type) { |
201 | case MPTT_REXMT: |
202 | mp_tp->mpt_rxtstart = 0; |
203 | mp_tp->mpt_rxtshift = 0; |
204 | mp_tp->mpt_timer_vals = 0; |
205 | break; |
206 | case MPTT_TW: |
207 | /* NO-OP */ |
208 | break; |
209 | case MPTT_FASTCLOSE: |
210 | /* NO-OP */ |
211 | break; |
212 | default: |
213 | break; |
214 | } |
215 | } |
216 | |
217 | void |
218 | mptcp_cancel_all_timers(struct mptcb *mp_tp) |
219 | { |
220 | struct mptses *mpte = mp_tp->mpt_mpte; |
221 | |
222 | mptcp_cancel_urgency_timer(mpte); |
223 | |
224 | mptcp_cancel_timer(mp_tp, MPTT_REXMT); |
225 | mptcp_cancel_timer(mp_tp, MPTT_TW); |
226 | mptcp_cancel_timer(mp_tp, MPTT_FASTCLOSE); |
227 | } |
228 | |
229 | static void |
230 | mptcp_urgency_timer(void *param0, __unused void *param1) |
231 | { |
232 | struct mptses *mpte = (struct mptses *)param0; |
233 | struct socket *mp_so = mptetoso(mpte); |
234 | uint64_t time_now; |
235 | |
236 | socket_lock(so: mp_so, refcount: 1); |
237 | |
238 | time_now = mach_continuous_time(); |
239 | VERIFY(mp_so->so_usecount >= 0); |
240 | |
241 | os_log(mptcp_log_handle, "%s - %lx: timer at %llu now %llu usecount %u\n" , |
242 | __func__, (unsigned long)VM_KERNEL_ADDRPERM(mpte), mpte->mpte_time_target, time_now, mp_so->so_usecount); |
243 | |
244 | mptcp_check_subflows_and_add(mpte); |
245 | |
246 | mp_so->so_usecount--; |
247 | |
248 | socket_unlock(so: mp_so, refcount: 1); |
249 | } |
250 | |
251 | static void |
252 | mptcp_urgency_stop(void *param0, __unused void *param1) |
253 | { |
254 | struct mptses *mpte = (struct mptses *)param0; |
255 | struct socket *mp_so = mptetoso(mpte); |
256 | |
257 | socket_lock(so: mp_so, refcount: 1); |
258 | |
259 | VERIFY(mp_so->so_usecount >= 1); |
260 | |
261 | os_log(mptcp_log_handle, "%s - %lx: usecount %u\n" , |
262 | __func__, (unsigned long)VM_KERNEL_ADDRPERM(mpte), mp_so->so_usecount); |
263 | |
264 | mptcp_check_subflows_and_remove(mpte); |
265 | |
266 | mp_so->so_usecount--; |
267 | |
268 | socket_unlock(so: mp_so, refcount: 1); |
269 | } |
270 | |
271 | void |
272 | mptcp_init_urgency_timer(struct mptses *mpte) |
273 | { |
274 | /* thread_call_allocate never fails */ |
275 | mpte->mpte_time_thread = thread_call_allocate(func: mptcp_urgency_timer, param0: mpte); |
276 | mpte->mpte_stop_urgency = thread_call_allocate(func: mptcp_urgency_stop, param0: mpte); |
277 | } |
278 | |
279 | void |
280 | mptcp_set_urgency_timer(struct mptses *mpte) |
281 | { |
282 | struct socket *mp_so = mptetoso(mpte); |
283 | uint64_t time_now = 0; |
284 | boolean_t ret = FALSE; |
285 | |
286 | socket_lock_assert_owned(so: mp_so); |
287 | |
288 | VERIFY(mp_so->so_usecount >= 1); |
289 | |
290 | if (mpte->mpte_time_target == 0) { |
291 | /* Close subflows right now */ |
292 | |
293 | ret = thread_call_enter(call: mpte->mpte_stop_urgency); |
294 | |
295 | if (!ret) { |
296 | mp_so->so_usecount++; |
297 | } |
298 | |
299 | goto exit_log; |
300 | } |
301 | |
302 | time_now = mach_continuous_time(); |
303 | |
304 | if ((int64_t)(mpte->mpte_time_target - time_now) > 0) { |
305 | ret = thread_call_enter(call: mpte->mpte_stop_urgency); |
306 | |
307 | if (!ret) { |
308 | mp_so->so_usecount++; |
309 | } |
310 | |
311 | ret = thread_call_enter_delayed_with_leeway(call: mpte->mpte_time_thread, NULL, |
312 | deadline: mpte->mpte_time_target, leeway: 0, THREAD_CALL_CONTINUOUS); |
313 | |
314 | if (!ret) { |
315 | mp_so->so_usecount++; |
316 | } |
317 | } else if ((int64_t)(mpte->mpte_time_target - time_now) <= 0) { |
318 | /* Already passed the deadline, trigger subflows now */ |
319 | ret = thread_call_enter(call: mpte->mpte_time_thread); |
320 | |
321 | if (!ret) { |
322 | mp_so->so_usecount++; |
323 | } |
324 | } |
325 | |
326 | exit_log: |
327 | os_log(mptcp_log_handle, "%s - %lx: timer at %llu now %llu usecount %u ret %u\n" , |
328 | __func__, (unsigned long)VM_KERNEL_ADDRPERM(mpte), mpte->mpte_time_target, time_now, |
329 | mp_so->so_usecount, ret); |
330 | } |
331 | |
332 | static int |
333 | mptcp_cancel_urgency_timer(struct mptses *mpte) |
334 | { |
335 | struct socket *mp_so = mptetoso(mpte); |
336 | boolean_t ret; |
337 | |
338 | ret = thread_call_cancel(call: mpte->mpte_time_thread); |
339 | |
340 | os_log(mptcp_log_handle, "%s - %lx: Canceled timer thread usecount %u ret %u\n" , |
341 | __func__, (unsigned long)VM_KERNEL_ADDRPERM(mpte), mp_so->so_usecount, ret); |
342 | |
343 | mptcp_check_subflows_and_remove(mpte); |
344 | |
345 | if (ret) { |
346 | VERIFY(mp_so->so_usecount >= 1); |
347 | mp_so->so_usecount--; |
348 | } |
349 | |
350 | ret = thread_call_cancel(call: mpte->mpte_stop_urgency); |
351 | if (ret) { |
352 | VERIFY(mp_so->so_usecount >= 1); |
353 | mp_so->so_usecount--; |
354 | } |
355 | |
356 | return 0; |
357 | } |
358 | |