crypto/threads_win.c

   1 /*
   2  * Copyright 2016-2021 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 #  define USE_RWLOCK
  14 # endif
  15 #endif
  16
  17 #include <openssl/crypto.h>
  18
  19 #if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && defined(OPENSSL_SYS_WINDOWS)
  20
  21 # ifdef USE_RWLOCK
  22 typedef struct {
  23     SRWLOCK lock;
  24     int exclusive;
  25 } CRYPTO_win_rwlock;
  26 # endif
  27
  28 CRYPTO_RWLOCK *CRYPTO_THREAD_lock_new(void)
  29 {
  30     CRYPTO_RWLOCK *lock;
  31 # ifdef USE_RWLOCK
  32     CRYPTO_win_rwlock *rwlock;
  33
  34     if ((lock = OPENSSL_zalloc(sizeof(CRYPTO_win_rwlock))) == NULL)
  35         return NULL;
  36     rwlock = lock;
  37     InitializeSRWLock(&rwlock->lock);
  38 # else
  39
  40     if ((lock = OPENSSL_zalloc(sizeof(CRITICAL_SECTION))) == NULL) {
  41         /* Don't set error, to avoid recursion blowup. */
  42         return NULL;
  43     }
  44
  45 #  if !defined(_WIN32_WCE)
  46     /* 0x400 is the spin count value suggested in the documentation */
  47     if (!InitializeCriticalSectionAndSpinCount(lock, 0x400)) {
  48         OPENSSL_free(lock);
  49         return NULL;
  50     }
  51 #  else
  52     InitializeCriticalSection(lock);
  53 #  endif
  54 # endif
  55
  56     return lock;
  57 }
  58
  59 __owur int CRYPTO_THREAD_read_lock(CRYPTO_RWLOCK *lock)
  60 {
  61 # ifdef USE_RWLOCK
  62     CRYPTO_win_rwlock *rwlock = lock;
  63
  64     AcquireSRWLockShared(&rwlock->lock);
  65 # else
  66     EnterCriticalSection(lock);
  67 # endif
  68     return 1;
  69 }
  70
  71 __owur int CRYPTO_THREAD_write_lock(CRYPTO_RWLOCK *lock)
  72 {
  73 # ifdef USE_RWLOCK
  74     CRYPTO_win_rwlock *rwlock = lock;
  75
  76     AcquireSRWLockExclusive(&rwlock->lock);
  77     rwlock->exclusive = 1;
  78 # else
  79     EnterCriticalSection(lock);
  80 # endif
  81     return 1;
  82 }
  83
  84 int CRYPTO_THREAD_unlock(CRYPTO_RWLOCK *lock)
  85 {
  86 # ifdef USE_RWLOCK
  87     CRYPTO_win_rwlock *rwlock = lock;
  88
  89     if (rwlock->exclusive) {
  90         rwlock->exclusive = 0;
  91         ReleaseSRWLockExclusive(&rwlock->lock);
  92     } else {
  93         ReleaseSRWLockShared(&rwlock->lock);
  94     }
  95 # else
  96     LeaveCriticalSection(lock);
  97 # endif
  98     return 1;
  99 }
 100
 101 void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock)
 102 {
 103     if (lock == NULL)
 104         return;
 105
 106 # ifndef USE_RWLOCK
 107     DeleteCriticalSection(lock);
 108 # endif
 109     OPENSSL_free(lock);
 110
 111     return;
 112 }
 113
 114 # define ONCE_UNINITED     0
 115 # define ONCE_ININIT       1
 116 # define ONCE_DONE         2
 117
 118 /*
 119  * We don't use InitOnceExecuteOnce because that isn't available in WinXP which
 120  * we still have to support.
 121  */
 122 int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
 123 {
 124     LONG volatile *lock = (LONG *)once;
 125     LONG result;
 126
 127     if (*lock == ONCE_DONE)
 128         return 1;
 129
 130     do {
 131         result = InterlockedCompareExchange(lock, ONCE_ININIT, ONCE_UNINITED);
 132         if (result == ONCE_UNINITED) {
 133             init();
 134             *lock = ONCE_DONE;
 135             return 1;
 136         }
 137     } while (result == ONCE_ININIT);
 138
 139     return (*lock == ONCE_DONE);
 140 }
 141
 142 int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
 143 {
 144     *key = TlsAlloc();
 145     if (*key == TLS_OUT_OF_INDEXES)
 146         return 0;
 147
 148     return 1;
 149 }
 150
 151 void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *key)
 152 {
 153     DWORD last_error;
 154     void *ret;
 155
 156     /*
 157      * TlsGetValue clears the last error even on success, so that callers may
 158      * distinguish it successfully returning NULL or failing. It is documented
 159      * to never fail if the argument is a valid index from TlsAlloc, so we do
 160      * not need to handle this.
 161      *
 162      * However, this error-mangling behavior interferes with the caller's use of
 163      * GetLastError. In particular SSL_get_error queries the error queue to
 164      * determine whether the caller should look at the OS's errors. To avoid
 165      * destroying state, save and restore the Windows error.
 166      *
 167      * https://msdn.microsoft.com/en-us/library/windows/desktop/ms686812(v=vs.85).aspx
 168      */
 169     last_error = GetLastError();
 170     ret = TlsGetValue(*key);
 171     SetLastError(last_error);
 172     return ret;
 173 }
 174
 175 int CRYPTO_THREAD_set_local(CRYPTO_THREAD_LOCAL *key, void *val)
 176 {
 177     if (TlsSetValue(*key, val) == 0)
 178         return 0;
 179
 180     return 1;
 181 }
 182
 183 int CRYPTO_THREAD_cleanup_local(CRYPTO_THREAD_LOCAL *key)
 184 {
 185     if (TlsFree(*key) == 0)
 186         return 0;
 187
 188     return 1;
 189 }
 190
 191 CRYPTO_THREAD_ID CRYPTO_THREAD_get_current_id(void)
 192 {
 193     return GetCurrentThreadId();
 194 }
 195
 196 int CRYPTO_THREAD_compare_id(CRYPTO_THREAD_ID a, CRYPTO_THREAD_ID b)
 197 {
 198     return (a == b);
 199 }
 200
 201 int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
 202 {
 203     *ret = (int)InterlockedExchangeAdd((long volatile *)val, (long)amount) + amount;
 204     return 1;
 205 }
 206
 207 int CRYPTO_atomic_or(uint64_t *val, uint64_t op, uint64_t *ret,
 208                      CRYPTO_RWLOCK *lock)
 209 {
 210     *ret = (uint64_t)InterlockedOr64((LONG64 volatile *)val, (LONG64)op) | op;
 211     return 1;
 212 }
 213
 214 int CRYPTO_atomic_load(uint64_t *val, uint64_t *ret, CRYPTO_RWLOCK *lock)
 215 {
 216     *ret = (uint64_t)InterlockedOr64((LONG64 volatile *)val, 0);
 217     return 1;
 218 }
 219
 220 int openssl_init_fork_handlers(void)
 221 {
 222     return 0;
 223 }
 224
 225 int openssl_get_fork_id(void)
 226 {
 227     return 0;
 228 }
 229 #endif