rand

#include <wincrypt.h>

void f(){

    HCRYPTPROV hProv = 0;

    // Get a handle to the default PROV_RSA_FULL provider.

    if(!CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_SILENT)) {

     printf("Error %x during CryptAcquireContext!\n", GetLastError());

     return;

    }

    if(!CryptGenRandom(hProv, 8, pbData))

    //CryptGenRandom(hProv, len, b)


// Release the provider handle. 
if(!CryptReleaseContext(hProv, 0)) 
{ printf("Error %x during CryptReleaseContext!\n", GetLastError()); return; }

}



#pragma comment (lib, "crypt32.lib")


Cryptapi.lib

https://blog.csdn.net/iteye_15337/article/details/82249461

{ //what openssl does

BYTE buf[64];

/* poll the CryptoAPI PRNG */

/* The CryptoAPI returns sizeof(buf) bytes of randomness */

if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,

CRYPT_VERIFYCONTEXT)) {

if (CryptGenRandom(hProvider, sizeof(buf), buf))

RAND_add(buf, sizeof(buf), sizeof(buf));

CryptReleaseContext(hProvider, 0);

}

}