1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
5 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
6 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * a) Redistributions of source code must retain the above copyright notice,
12 * this list of conditions and the following disclaimer.
13 *
14 * b) Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the distribution.
17 *
18 * c) Neither the name of Cisco Systems, Inc. nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
24 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
26 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
32 * THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35 #if defined(__Userspace__)
36 #include <sys/types.h>
37 #if !defined (__Userspace_os_Windows)
38 #include <sys/wait.h>
39 #include <unistd.h>
40 #include <pthread.h>
41 #endif
42 #if defined(__Userspace_os_NaCl)
43 #include <sys/select.h>
44 #endif
45 #include <stdlib.h>
46 #include <string.h>
47 #include <stdio.h>
48 #include <errno.h>
49 #include <user_atomic.h>
50 #include <netinet/sctp_sysctl.h>
51 #include <netinet/sctp_pcb.h>
52 #else
53 #include <netinet/sctp_os.h>
54 #include <netinet/sctp_callout.h>
55 #include <netinet/sctp_pcb.h>
56 #endif
57 #include <netinet/sctputil.h>
58
59 /*
60 * Callout/Timer routines for OS that doesn't have them
61 */
62 #if defined(__APPLE__) || defined(__Userspace__)
63 static uint32_t ticks = 0;
64 #else
65 extern int ticks;
66 #endif
67
sctp_get_tick_count(void)68 uint32_t sctp_get_tick_count(void) {
69 uint32_t ret;
70
71 SCTP_TIMERQ_LOCK();
72 ret = ticks;
73 SCTP_TIMERQ_UNLOCK();
74 return ret;
75 }
76
77 /*
78 * SCTP_TIMERQ_LOCK protects:
79 * - SCTP_BASE_INFO(callqueue)
80 * - sctp_os_timer_next: next timer to check
81 */
82 static sctp_os_timer_t *sctp_os_timer_next = NULL;
83
84 void
sctp_os_timer_init(sctp_os_timer_t * c)85 sctp_os_timer_init(sctp_os_timer_t *c)
86 {
87 memset(c, 0, sizeof(*c));
88 }
89
90 int
sctp_os_timer_start(sctp_os_timer_t * c,uint32_t to_ticks,void (* ftn)(void *),void * arg)91 sctp_os_timer_start(sctp_os_timer_t *c, uint32_t to_ticks, void (*ftn) (void *),
92 void *arg)
93 {
94 int ret = 0;
95
96 /* paranoia */
97 if ((c == NULL) || (ftn == NULL))
98 return (ret);
99
100 SCTP_TIMERQ_LOCK();
101 /* check to see if we're rescheduling a timer */
102 if (c->c_flags & SCTP_CALLOUT_PENDING) {
103 ret = 1;
104 if (c == sctp_os_timer_next) {
105 sctp_os_timer_next = TAILQ_NEXT(c, tqe);
106 }
107 TAILQ_REMOVE(&SCTP_BASE_INFO(callqueue), c, tqe);
108 /*
109 * part of the normal "stop a pending callout" process
110 * is to clear the CALLOUT_ACTIVE and CALLOUT_PENDING
111 * flags. We don't bother since we are setting these
112 * below and we still hold the lock.
113 */
114 }
115
116 /*
117 * We could unlock/splx here and lock/spl at the TAILQ_INSERT_TAIL,
118 * but there's no point since doing this setup doesn't take much time.
119 */
120 if (to_ticks == 0)
121 to_ticks = 1;
122
123 c->c_arg = arg;
124 c->c_flags = (SCTP_CALLOUT_ACTIVE | SCTP_CALLOUT_PENDING);
125 c->c_func = ftn;
126 c->c_time = ticks + to_ticks;
127 TAILQ_INSERT_TAIL(&SCTP_BASE_INFO(callqueue), c, tqe);
128 SCTP_TIMERQ_UNLOCK();
129 return (ret);
130 }
131
132 int
sctp_os_timer_stop(sctp_os_timer_t * c)133 sctp_os_timer_stop(sctp_os_timer_t *c)
134 {
135 SCTP_TIMERQ_LOCK();
136 /*
137 * Don't attempt to delete a callout that's not on the queue.
138 */
139 if (!(c->c_flags & SCTP_CALLOUT_PENDING)) {
140 c->c_flags &= ~SCTP_CALLOUT_ACTIVE;
141 SCTP_TIMERQ_UNLOCK();
142 return (0);
143 }
144 c->c_flags &= ~(SCTP_CALLOUT_ACTIVE | SCTP_CALLOUT_PENDING);
145 if (c == sctp_os_timer_next) {
146 sctp_os_timer_next = TAILQ_NEXT(c, tqe);
147 }
148 TAILQ_REMOVE(&SCTP_BASE_INFO(callqueue), c, tqe);
149 SCTP_TIMERQ_UNLOCK();
150 return (1);
151 }
152
153 void
sctp_handle_tick(uint32_t elapsed_ticks)154 sctp_handle_tick(uint32_t elapsed_ticks)
155 {
156 sctp_os_timer_t *c;
157 void (*c_func)(void *);
158 void *c_arg;
159
160 SCTP_TIMERQ_LOCK();
161 /* update our tick count */
162 ticks += elapsed_ticks;
163 c = TAILQ_FIRST(&SCTP_BASE_INFO(callqueue));
164 while (c) {
165 if (SCTP_UINT32_GE(ticks, c->c_time)) {
166 sctp_os_timer_next = TAILQ_NEXT(c, tqe);
167 TAILQ_REMOVE(&SCTP_BASE_INFO(callqueue), c, tqe);
168 c_func = c->c_func;
169 c_arg = c->c_arg;
170 c->c_flags &= ~SCTP_CALLOUT_PENDING;
171 SCTP_TIMERQ_UNLOCK();
172 c_func(c_arg);
173 SCTP_TIMERQ_LOCK();
174 c = sctp_os_timer_next;
175 } else {
176 c = TAILQ_NEXT(c, tqe);
177 }
178 }
179 sctp_os_timer_next = NULL;
180 SCTP_TIMERQ_UNLOCK();
181 }
182
183 #if defined(__APPLE__)
184 void
sctp_timeout(void * arg SCTP_UNUSED)185 sctp_timeout(void *arg SCTP_UNUSED)
186 {
187 sctp_handle_tick(SCTP_BASE_VAR(sctp_main_timer_ticks));
188 sctp_start_main_timer();
189 }
190 #endif
191
192 #if defined(__Userspace__)
193 #define TIMEOUT_INTERVAL 10
194
195 void *
user_sctp_timer_iterate(void * arg)196 user_sctp_timer_iterate(void *arg)
197 {
198 sctp_userspace_set_threadname("SCTP timer");
199 for (;;) {
200 #if defined (__Userspace_os_Windows)
201 Sleep(TIMEOUT_INTERVAL);
202 #else
203 struct timespec amount, remaining;
204
205 remaining.tv_sec = 0;
206 remaining.tv_nsec = TIMEOUT_INTERVAL * 1000 * 1000;
207 do {
208 amount = remaining;
209 } while (nanosleep(&amount, &remaining) == -1);
210 #endif
211 if (atomic_cmpset_int(&SCTP_BASE_VAR(timer_thread_should_exit), 1, 1)) {
212 break;
213 }
214 sctp_handle_tick(sctp_msecs_to_ticks(TIMEOUT_INTERVAL));
215 }
216 return (NULL);
217 }
218
219 void
sctp_start_timer(void)220 sctp_start_timer(void)
221 {
222 /*
223 * No need to do SCTP_TIMERQ_LOCK_INIT();
224 * here, it is being done in sctp_pcb_init()
225 */
226 int rc;
227
228 rc = sctp_userspace_thread_create(&SCTP_BASE_VAR(timer_thread), user_sctp_timer_iterate);
229 if (rc) {
230 SCTP_PRINTF("ERROR; return code from sctp_thread_create() is %d\n", rc);
231 } else {
232 SCTP_BASE_VAR(timer_thread_started) = 1;
233 }
234 }
235
236 #endif
237