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 */
52static u_int32_t mptcp_rto = 3;
53SYSCTL_INT(_net_inet_mptcp, OID_AUTO, rto, CTLFLAG_RW | CTLFLAG_LOCKED,
54 &mptcp_rto, 0, "MPTCP Retransmission Timeout");
55
56static int mptcp_nrtos = 3;
57SYSCTL_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 */
63static u_int32_t mptcp_tw = 60;
64SYSCTL_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
69static int
70mptcp_timer_demux(struct mptses *mpte, uint32_t now_msecs)
71{
72 struct mptcb *mp_tp = NULL;
73 mp_tp = mpte->mpte_mptcb;
74 int resched_timer = 0;
75
76 DTRACE_MPTCP2(timer, struct mptses *, mpte, struct mptcb *, mp_tp);
77
78 mpte_lock_assert_held(mpte);
79 switch (mp_tp->mpt_timer_vals) {
80 case MPTT_REXMT:
81 if (mp_tp->mpt_rxtstart == 0)
82 break;
83 if ((now_msecs - mp_tp->mpt_rxtstart) >
84 (mptcp_rto*hz)) {
85 if (MPTCP_SEQ_GT(mp_tp->mpt_snduna, mp_tp->mpt_rtseq)) {
86 mp_tp->mpt_timer_vals = 0;
87 mp_tp->mpt_rtseq = 0;
88 break;
89 }
90 mp_tp->mpt_rxtshift++;
91 if (mp_tp->mpt_rxtshift > mptcp_nrtos) {
92 mp_tp->mpt_softerror = ETIMEDOUT;
93 DTRACE_MPTCP1(error, struct mptcb *, mp_tp);
94 } else {
95 mp_tp->mpt_sndnxt = mp_tp->mpt_rtseq;
96 os_log_info(mptcp_log_handle,
97 "%s: REXMT %d sndnxt %u\n",
98 __func__, mp_tp->mpt_rxtshift,
99 (uint32_t)mp_tp->mpt_sndnxt);
100 mptcp_output(mpte);
101 }
102 } else {
103 resched_timer = 1;
104 }
105 break;
106 case MPTT_TW:
107 /* Allows for break before make XXX */
108 if (mp_tp->mpt_timewait == 0)
109 VERIFY(0);
110 if ((now_msecs - mp_tp->mpt_timewait) >
111 (mptcp_tw * hz)) {
112 mp_tp->mpt_softerror = ETIMEDOUT;
113 DTRACE_MPTCP1(error, struct mptcb *, mp_tp);
114 } else {
115 resched_timer = 1;
116 }
117 break;
118 case MPTT_FASTCLOSE:
119 /* TODO XXX */
120 break;
121 default:
122 break;
123 }
124
125 return (resched_timer);
126}
127
128uint32_t
129mptcp_timer(struct mppcbinfo *mppi)
130{
131 struct mppcb *mpp, *tmpp;
132 struct timeval now;
133 u_int32_t now_msecs;
134 uint32_t resched_timer = 0;
135
136 LCK_MTX_ASSERT(&mppi->mppi_lock, LCK_MTX_ASSERT_OWNED);
137
138 microuptime(&now);
139 now_msecs = TIMEVAL_TO_HZ(now);
140 TAILQ_FOREACH_SAFE(mpp, &mppi->mppi_pcbs, mpp_entry, tmpp) {
141 struct socket *mp_so;
142 struct mptses *mpte;
143
144 mp_so = mpp->mpp_socket;
145 VERIFY(mp_so != NULL);
146 mpte = mptompte(mpp);
147 VERIFY(mpte != NULL);
148 mpte_lock(mpte);
149 VERIFY(mpp->mpp_flags & MPP_ATTACHED);
150
151 if (mptcp_timer_demux(mpte, now_msecs))
152 resched_timer = 1;
153 mpte_unlock(mpte);
154 }
155
156 return (resched_timer);
157}
158
159void
160mptcp_start_timer(struct mptses *mpte, int timer_type)
161{
162 struct timeval now;
163 struct mptcb *mp_tp = mpte->mpte_mptcb;
164
165 microuptime(&now);
166
167 DTRACE_MPTCP2(start__timer, struct mptcb *, mp_tp, int, timer_type);
168 mptcplog((LOG_DEBUG, "MPTCP Socket: %s: %d\n", __func__, timer_type),
169 MPTCP_SOCKET_DBG, MPTCP_LOGLVL_VERBOSE);
170
171 mpte_lock_assert_held(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
195void
196mptcp_cancel_timer(struct mptcb *mp_tp, int timer_type)
197{
198 mpte_lock_assert_held(mp_tp->mpt_mpte);
199 DTRACE_MPTCP2(cancel__timer, struct mptcb *, mp_tp, int, timer_type);
200
201 switch (timer_type) {
202 case MPTT_REXMT:
203 mp_tp->mpt_rxtstart = 0;
204 mp_tp->mpt_rxtshift = 0;
205 mp_tp->mpt_timer_vals = 0;
206 break;
207 case MPTT_TW:
208 /* NO-OP */
209 break;
210 case MPTT_FASTCLOSE:
211 /* NO-OP */
212 break;
213 default:
214 break;
215 }
216}
217
218void
219mptcp_cancel_all_timers(struct mptcb *mp_tp)
220{
221 mptcp_cancel_timer(mp_tp, MPTT_REXMT);
222 mptcp_cancel_timer(mp_tp, MPTT_TW);
223 mptcp_cancel_timer(mp_tp, MPTT_FASTCLOSE);
224}
225