crypto/threads_win.c

   1 /*
   2  * Copyright 2016-2020 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 #if defined(_WIN32)
  11 # include <windows.h>
  12 # if defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x600
  13 #  include <synchapi.h>
  14 #  define USE_RWLOCK
  15 # endif
  16 #endif
  17
  18 #include <openssl/crypto.h>
  19
  20 #if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && defined(OPENSSL_SYS_WINDOWS)
  21
  22 # ifdef USE_RWLOCK
  23 typedef struct {
  24     SRWLOCK lock;
  25     int exclusive;
  26 } CRYPTO_win_rwlock;
  27 # endif
  28
  29 CRYPTO_RWLOCK *CRYPTO_THREAD_lock_new(void)
  30 {
  31     CRYPTO_RWLOCK *lock;
  32 # ifdef USE_RWLOCK
  33     CRYPTO_win_rwlock *rwlock;
  34
  35     if ((lock = OPENSSL_zalloc(sizeof(CRYPTO_win_rwlock))) == NULL)
  36         return NULL;
  37     rwlock = lock;
  38     InitializeSRWLock(&rwlock->lock);
  39 # else
  40
  41     if ((lock = OPENSSL_zalloc(sizeof(CRITICAL_SECTION))) == NULL) {
  42         /* Don't set error, to avoid recursion blowup. */
  43         return NULL;
  44     }
  45
  46 #  if !defined(_WIN32_WCE)
  47     /* 0x400 is the spin count value suggested in the documentation */
  48     if (!InitializeCriticalSectionAndSpinCount(lock, 0x400)) {
  49         OPENSSL_free(lock);
  50         return NULL;
  51     }
  52 #  else
  53     InitializeCriticalSection(lock);
  54 #  endif
  55 # endif
  56
  57     return lock;
  58 }
  59
  60 int CRYPTO_THREAD_read_lock(CRYPTO_RWLOCK *lock)
  61 {
  62 # ifdef USE_RWLOCK
  63     CRYPTO_win_rwlock *rwlock = lock;
  64
  65     AcquireSRWLockShared(&rwlock->lock);
  66 # else
  67     EnterCriticalSection(lock);
  68 # endif
  69     return 1;
  70 }
  71
  72 int CRYPTO_THREAD_write_lock(CRYPTO_RWLOCK *lock)
  73 {
  74 # ifdef USE_RWLOCK
  75     CRYPTO_win_rwlock *rwlock = lock;
  76
  77     AcquireSRWLockExclusive(&rwlock->lock);
  78     rwlock->exclusive = 1;
  79 # else
  80     EnterCriticalSection(lock);
  81 # endif
  82     return 1;
  83 }
  84
  85 int CRYPTO_THREAD_unlock(CRYPTO_RWLOCK *lock)
  86 {
  87 # ifdef USE_RWLOCK
  88     CRYPTO_win_rwlock *rwlock = lock;
  89
  90     if (rwlock->exclusive) {
  91         rwlock->exclusive = 0;
  92         ReleaseSRWLockExclusive(&rwlock->lock);
  93     } else {
  94         ReleaseSRWLockShared(&rwlock->lock);
  95     }
  96 # else
  97     LeaveCriticalSection(lock);
  98 # endif
  99     return 1;
 100 }
 101
 102 void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock)
 103 {
 104     if (lock == NULL)
 105         return;
 106
 107 # ifndef USE_RWLOCK
 108     DeleteCriticalSection(lock);
 109 # endif
 110     OPENSSL_free(lock);
 111
 112     return;
 113 }
 114
 115 # define ONCE_UNINITED     0
 116 # define ONCE_ININIT       1
 117 # define ONCE_DONE         2
 118
 119 /*
 120  * We don't use InitOnceExecuteOnce because that isn't available in WinXP which
 121  * we still have to support.
 122  */
 123 int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
 124 {
 125     LONG volatile *lock = (LONG *)once;
 126     LONG result;
 127
 128     if (*lock == ONCE_DONE)
 129         return 1;
 130
 131     do {
 132         result = InterlockedCompareExchange(lock, ONCE_ININIT, ONCE_UNINITED);
 133         if (result == ONCE_UNINITED) {
 134             init();
 135             *lock = ONCE_DONE;
 136             return 1;
 137         }
 138     } while (result == ONCE_ININIT);
 139
 140     return (*lock == ONCE_DONE);
 141 }
 142
 143 int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
 144 {
 145     *key = TlsAlloc();
 146     if (*key == TLS_OUT_OF_INDEXES)
 147         return 0;
 148
 149     return 1;
 150 }
 151
 152 void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *key)
 153 {
 154     DWORD last_error;
 155     void *ret;
 156
 157     /*
 158      * TlsGetValue clears the last error even on success, so that callers may
 159      * distinguish it successfully returning NULL or failing. It is documented
 160      * to never fail if the argument is a valid index from TlsAlloc, so we do
 161      * not need to handle this.
 162      *
 163      * However, this error-mangling behavior interferes with the caller's use of
 164      * GetLastError. In particular SSL_get_error queries the error queue to
 165      * determine whether the caller should look at the OS's errors. To avoid
 166      * destroying state, save and restore the Windows error.
 167      *
 168      * https://msdn.microsoft.com/en-us/library/windows/desktop/ms686812(v=vs.85).aspx
 169      */
 170     last_error = GetLastError();
 171     ret = TlsGetValue(*key);
 172     SetLastError(last_error);
 173     return ret;
 174 }
 175
 176 int CRYPTO_THREAD_set_local(CRYPTO_THREAD_LOCAL *key, void *val)
 177 {
 178     if (TlsSetValue(*key, val) == 0)
 179         return 0;
 180
 181     return 1;
 182 }
 183
 184 int CRYPTO_THREAD_cleanup_local(CRYPTO_THREAD_LOCAL *key)
 185 {
 186     if (TlsFree(*key) == 0)
 187         return 0;
 188
 189     return 1;
 190 }
 191
 192 CRYPTO_THREAD_ID CRYPTO_THREAD_get_current_id(void)
 193 {
 194     return GetCurrentThreadId();
 195 }
 196
 197 int CRYPTO_THREAD_compare_id(CRYPTO_THREAD_ID a, CRYPTO_THREAD_ID b)
 198 {
 199     return (a == b);
 200 }
 201
 202 int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
 203 {
 204     *ret = (int)InterlockedExchangeAdd((long volatile *)val, (long)amount) + amount;
 205     return 1;
 206 }
 207
 208 int CRYPTO_atomic_or(uint64_t *val, uint64_t op, uint64_t *ret,
 209                      CRYPTO_RWLOCK *lock)
 210 {
 211     *ret = (uint64_t)InterlockedOr64((LONG64 volatile *)val, (LONG64)op) | op;
 212     return 1;
 213 }
 214
 215 int CRYPTO_atomic_load(uint64_t *val, uint64_t *ret, CRYPTO_RWLOCK *lock)
 216 {
 217     *ret = (uint64_t)InterlockedOr64((LONG64 volatile *)val, 0);
 218     return 1;
 219 }
 220
 221 int openssl_init_fork_handlers(void)
 222 {
 223     return 0;
 224 }
 225
 226 int openssl_get_fork_id(void)
 227 {
 228     return 0;
 229 }
 230 #endif