crypto/sleep.c

   1 /*
   2  * Copyright 2022-2023 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 #include <unistd.h>
  16
  17 void OSSL_sleep(uint64_t millis)
  18 {
  19 # ifdef OPENSSL_SYS_VXWORKS
  20     struct timespec ts;
  21
  22     ts.tv_sec = (long int) (millis / 1000);
  23     ts.tv_nsec = (long int) (millis % 1000) * 1000000ul;
  24     nanosleep(&ts, NULL);
  25 # elif defined(__TANDEM)
  26 #  if !defined(_REENTRANT)
  27 #   include <cextdecs.h(PROCESS_DELAY_)>
  28
  29     /* HPNS does not support usleep for non threaded apps */
  30     PROCESS_DELAY_(millis * 1000);
  31 #  elif defined(_SPT_MODEL_)
  32 #   include <spthread.h>
  33 #   include <spt_extensions.h>
  34
  35     usleep(millis * 1000);
  36 #  else
  37     usleep(millis * 1000);
  38 #  endif
  39 # else
  40     unsigned int s = (unsigned int)(millis / 1000);
  41     unsigned int us = (unsigned int)((millis % 1000) * 1000);
  42
  43     sleep(s);
  44     usleep(us);
  45 # endif
  46 }
  47 #elif defined(_WIN32) && !defined(OPENSSL_SYS_UEFI)
  48 # include <windows.h>
  49
  50 void OSSL_sleep(uint64_t millis)
  51 {
  52     /*
  53      * Windows' Sleep() takes a DWORD argument, which is smaller than
  54      * a uint64_t, so we need to limit it to 49 days, which should be enough.
  55      */
  56     DWORD limited_millis = (DWORD)-1;
  57
  58     if (millis < limited_millis)
  59         limited_millis = (DWORD)millis;
  60     Sleep(limited_millis);
  61 }
  62
  63 #else
  64 /* Fallback to a busy wait */
  65 # include "internal/time.h"
  66
  67 static void ossl_sleep_secs(uint64_t secs)
  68 {
  69     /*
  70      * sleep() takes an unsigned int argument, which is smaller than
  71      * a uint64_t, so it needs to be limited to 136 years which
  72      * should be enough even for Sleeping Beauty.
  73      */
  74     unsigned int limited_secs = UINT_MAX;
  75
  76     if (secs < limited_secs)
  77         limited_secs = (unsigned int)secs;
  78     sleep(limited_secs);
  79 }
  80
  81 static void ossl_sleep_millis(uint64_t millis)
  82 {
  83     const OSSL_TIME finish
  84         = ossl_time_add(ossl_time_now(), ossl_ms2time(millis));
  85
  86     while (ossl_time_compare(ossl_time_now(), finish) < 0)
  87         /* busy wait */ ;
  88 }
  89
  90 void OSSL_sleep(uint64_t millis)
  91 {
  92     ossl_sleep_secs(millis / 1000);
  93     ossl_sleep_millis(millis % 1000);
  94 }
  95 #endif /* defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__) */