1 /*
2 * Copyright 2022-2024 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <openssl/crypto.h>
11 #include "internal/e_os.h"
12
13 /* system-specific variants defining OSSL_sleep() */
14 #if defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__)
15
16 # if defined(OPENSSL_USE_USLEEP) \
17 || defined(__DJGPP__) \
18 || (defined(__TANDEM) && defined(_REENTRANT))
19
20 /*
21 * usleep() was made obsolete by POSIX.1-2008, and nanosleep()
22 * should be used instead. However, nanosleep() isn't implemented
23 * on the platforms given above, so we still use it for those.
24 * Also, OPENSSL_USE_USLEEP can be defined to enable the use of
25 * usleep, if it turns out that nanosleep() is unavailable.
26 */
27
28 # include <unistd.h>
OSSL_sleep(uint64_t millis)29 void OSSL_sleep(uint64_t millis)
30 {
31 unsigned int s = (unsigned int)(millis / 1000);
32 unsigned int us = (unsigned int)((millis % 1000) * 1000);
33
34 if (s > 0)
35 sleep(s);
36 /*
37 * On NonStop with the PUT thread model, thread context switch is
38 * cooperative, with usleep() being a "natural" context switch point.
39 * We avoid checking us > 0 here, to allow that context switch to
40 * happen.
41 */
42 usleep(us);
43 }
44
45 # elif defined(__TANDEM) && !defined(_REENTRANT)
46
47 # include <cextdecs.h(PROCESS_DELAY_)>
OSSL_sleep(uint64_t millis)48 void OSSL_sleep(uint64_t millis)
49 {
50 /* HPNS does not support usleep for non threaded apps */
51 PROCESS_DELAY_(millis * 1000);
52 }
53
54 # else
55
56 /* nanosleep is defined by POSIX.1-2001 */
57 # include <time.h>
OSSL_sleep(uint64_t millis)58 void OSSL_sleep(uint64_t millis)
59 {
60 struct timespec ts;
61
62 ts.tv_sec = (long int) (millis / 1000);
63 ts.tv_nsec = (long int) (millis % 1000) * 1000000ul;
64 nanosleep(&ts, NULL);
65 }
66
67 # endif
68 #elif defined(_WIN32) && !defined(OPENSSL_SYS_UEFI)
69 # include <windows.h>
70
OSSL_sleep(uint64_t millis)71 void OSSL_sleep(uint64_t millis)
72 {
73 /*
74 * Windows' Sleep() takes a DWORD argument, which is smaller than
75 * a uint64_t, so we need to limit it to 49 days, which should be enough.
76 */
77 DWORD limited_millis = (DWORD)-1;
78
79 if (millis < limited_millis)
80 limited_millis = (DWORD)millis;
81 Sleep(limited_millis);
82 }
83
84 #else
85 /* Fallback to a busy wait */
86 # include "internal/time.h"
87
ossl_sleep_secs(uint64_t secs)88 static void ossl_sleep_secs(uint64_t secs)
89 {
90 /*
91 * sleep() takes an unsigned int argument, which is smaller than
92 * a uint64_t, so it needs to be limited to 136 years which
93 * should be enough even for Sleeping Beauty.
94 */
95 unsigned int limited_secs = UINT_MAX;
96
97 if (secs < limited_secs)
98 limited_secs = (unsigned int)secs;
99 sleep(limited_secs);
100 }
101
ossl_sleep_millis(uint64_t millis)102 static void ossl_sleep_millis(uint64_t millis)
103 {
104 const OSSL_TIME finish
105 = ossl_time_add(ossl_time_now(), ossl_ms2time(millis));
106
107 while (ossl_time_compare(ossl_time_now(), finish) < 0)
108 /* busy wait */ ;
109 }
110
OSSL_sleep(uint64_t millis)111 void OSSL_sleep(uint64_t millis)
112 {
113 ossl_sleep_secs(millis / 1000);
114 ossl_sleep_millis(millis % 1000);
115 }
116 #endif /* defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__) */
117
