Hi,
According to microsoft documentation at:
https://docs.microsoft.com/en-us/windows/win32/api/wincrypt/nf-wincrypt-cryptgenrandom
The function CryptGenRandom is deprecated, and may can be removed in future
release.
This patch add support to use BCryptGenRandom.
BCryptGenRandom apparently works without having to set up an environment before
calling.
The drawback, its change causes need to link to bcrypt.lib.
regards,
Ranier Vilela
diff --git a/src/port/pg_strong_random.c b/src/port/pg_strong_random.c
index 6be5874cbf..8199f89a37 100644
--- a/src/port/pg_strong_random.c
+++ b/src/port/pg_strong_random.c
@@ -28,10 +28,20 @@
#include <openssl/rand.h>
#endif
#ifdef USE_WIN32_RANDOM
-#include <wincrypt.h>
+#if defined(_MSC_VER) && _MSC_VER >= 1900 \
+ && defined(MIN_WINNT) && MIN_WINNT >= 0x0600
+#define USE_WIN32_BCRYPTGENRANDOM
+#endif
#endif
-#ifdef USE_WIN32_RANDOM
+#ifdef USE_WIN32_BCRYPTGENRANDOM
+#include <bcrypt.h>
+#ifndef STATUS_SUCCESS
+ #define STATUS_SUCCESS ((NTSTATUS)0x00000000L)
+#endif
+#elif USE_WIN32_RANDOM
+#include <wincrypt.h>
+
/*
* Cache a global crypto provider that only gets freed when the process
* exits, in case we need random numbers more than once.
@@ -85,8 +95,9 @@ random_from_file(const char *filename, void *buf, size_t len)
* We support a number of sources:
*
* 1. OpenSSL's RAND_bytes()
- * 2. Windows' CryptGenRandom() function
- * 3. /dev/urandom
+ * 2. Windows' BCryptGenRandom() function
+ * 3. Windows' CryptGenRandom() function
+ * 4. /dev/urandom
*
* The configure script will choose which one to use, and set
* a USE_*_RANDOM flag accordingly.
@@ -139,6 +150,10 @@ pg_strong_random(void *buf, size_t len)
/*
* Windows has CryptoAPI for strong cryptographic numbers.
*/
+#elif defined(USE_WIN32_BCRYPTGENRANDOM)
+ return (BCryptGenRandom(NULL, buf, len,
+ BCRYPT_USE_SYSTEM_PREFERRED_RNG) == STATUS_SUCCESS);
+
#elif defined(USE_WIN32_RANDOM)
if (hProvider == 0)
{
