crypto/rand/rand_win.c

   1 /*
   2  * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 "internal/cryptlib.h"
  11 #include <openssl/rand.h>
  12 #include "rand_lcl.h"
  13
  14 #if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
  15
  16 # ifndef OPENSSL_RAND_SEED_OS
  17 #  error "Unsupported seeding method configured; must be os"
  18 # endif
  19
  20 # include <windows.h>
  21 /* On Windows 7 or higher use BCrypt instead of the legacy CryptoAPI */
  22 # if defined(_MSC_VER) && defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0601
  23 #  define USE_BCRYPTGENRANDOM
  24 # endif
  25
  26 # ifdef USE_BCRYPTGENRANDOM
  27 #  include <bcrypt.h>
  28 #  pragma comment(lib, "bcrypt.lib")
  29 #  ifndef STATUS_SUCCESS
  30 #   define STATUS_SUCCESS ((NTSTATUS)0x00000000L)
  31 #  endif
  32 # else
  33 #  include <wincrypt.h>
  34 /*
  35  * Intel hardware RNG CSP -- available from
  36  * http://developer.intel.com/design/security/rng/redist_license.htm
  37  */
  38 #  define PROV_INTEL_SEC 22
  39 #  define INTEL_DEF_PROV L"Intel Hardware Cryptographic Service Provider"
  40 # endif
  41
  42 int RAND_poll_ex(RAND_poll_fn cb, void *arg)
  43 {
  44 # ifndef USE_BCRYPTGENRANDOM
  45     HCRYPTPROV hProvider;
  46 # endif
  47     DWORD w;
  48     BYTE buf[RANDOMNESS_NEEDED];
  49     int ok = 0;
  50
  51 # ifdef OPENSSL_RAND_SEED_RDTSC
  52     rand_read_tsc(cb, arg);
  53 # endif
  54 # ifdef OPENSSL_RAND_SEED_RDCPU
  55     if (rand_read_cpu(cb, arg))
  56         ok++;
  57 # endif
  58
  59 # ifdef USE_BCRYPTGENRANDOM
  60     if (BCryptGenRandom(NULL, buf, (ULONG)sizeof(buf),
  61                         BCRYPT_USE_SYSTEM_PREFERRED_RNG) != STATUS_SUCCESS)
  62         return 0;
  63     cb(arg, buf, sizeof(buf), sizeof(buf));
  64     return 1;
  65 # else
  66     /* poll the CryptoAPI PRNG */
  67     if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
  68                              CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
  69         if (CryptGenRandom(hProvider, (DWORD)sizeof(buf), buf) != 0) {
  70             cb(arg, buf, sizeof(buf), sizeof(buf));
  71             ok++;
  72         }
  73         CryptReleaseContext(hProvider, 0);
  74     }
  75
  76     /* poll the Pentium PRG with CryptoAPI */
  77     if (CryptAcquireContextW(&hProvider, NULL, INTEL_DEF_PROV, PROV_INTEL_SEC,
  78                              CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
  79         if (CryptGenRandom(hProvider, (DWORD)sizeof(buf), buf) != 0) {
  80             cb(arg, buf, sizeof(buf), sizeof(buf));
  81             ok++;
  82         }
  83         CryptReleaseContext(hProvider, 0);
  84     }
  85 # endif
  86
  87     return ok ? 1 : 0;
  88 }
  89
  90 #if OPENSSL_API_COMPAT < 0x10100000L
  91 int RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam)
  92 {
  93     RAND_poll();
  94     return RAND_status();
  95 }
  96
  97 void RAND_screen(void)
  98 {
  99     RAND_poll();
 100 }
 101 #endif
 102
 103 #endif