crypto lab 2

#include <iostream>
#include <string>
#include <Windows.h>
#include <wincrypt.h>

using namespace std;

// вывод ошибок
void ErrorHandling(string message)
{
    DWORD dw = GetLastError();
    cout << "Error with: " << message << "\n";
    cout << "Error code: " << dw << "\n";
}

int main()
{
    HCRYPTPROV  hCryptProv;
    HCRYPTHASH  hHash;
    HCRYPTHASH  hDuplicatedHash;
    if (CryptAcquireContext(
        &hCryptProv,
        nullptr,
        nullptr,
        PROV_RSA_FULL,
        0))
    {
        cout << "CryptAcquireContext complete. \n";
    }
    else
    {
        ErrorHandling("Acquisition of context failed.");
    }

    // получить дескриптор хэш объекта

    if (CryptCreateHash(
        hCryptProv,
        CALG_MD5,
        0,
        0,
        &hHash))
    {
        cout << "An empty hash object has been created. \n";
    }
    else
    {
        ErrorHandling("CryptBeginHash");
    }

    string input = "qwerty";

    if (CryptHashData(
        hHash, reinterpret_cast<const BYTE*>(input.c_str()), input.size(),0
    ))
    {
        cout << "CryptHashData executed successfully\n";
    }
    else
    {
        ErrorHandling("CryptHashData");
    }



    if (CryptDuplicateHash(
        hHash,
        nullptr,
        0,
        &hDuplicatedHash
    ))
    {
        cout << "The hash has been duplicated. \n";
    }
    else
    {
        ErrorHandling("CryptDuplicateHash");
    }

    BYTE*        pbHash;
    DWORD        dwHashLen;
    DWORD        dwHashLenSize = sizeof(DWORD);

    if (CryptGetHashParam(
        hDuplicatedHash,
        HP_HASHSIZE,
        reinterpret_cast<BYTE*>(&dwHashLen),
        &dwHashLenSize,
        0
    ))
    {
        cout << "CryptGetHashParam HP_HASHSIZE executed successfully\n";
    }
    else
    {
        ErrorHandling("CryptGetHashParam failed to get size.");

    }

    if ((pbHash = static_cast<BYTE*>(malloc(dwHashLen))))
        cout << "Allocation pbHash success\n";
    else
        cout << "Allocation failed\n";


    string res;
    if (CryptGetHashParam(
        hHash,
        HP_HASHVAL,
        pbHash,
        &dwHashLen,
        0))
    {
        if (pbHash == nullptr)
        {
            cout << "system error\n";
            exit(1);
        }
        // первый вариант вывода
        cout << "1 hash is: ";
        for (size_t i = 0; i!= 16; ++i)
        {
            res += "0123456789ABCDEF"[pbHash[i] / 16];
            res += "0123456789ABCDEF"[pbHash[i] % 16];
        }
        cout << res << "\n";
        // второй вариант вывода
        cout << "2 hash is: ";
        for(int i = 0 ; i < dwHashLen ; i++)
        {
           printf("%02x",pbHash[i]);
        }
        cout << "\n";
    }
    else
    {
        ErrorHandling("CryptGetHashParam\n");
    }

    if (hHash)
        CryptDestroyHash(hHash);
    if (hDuplicatedHash)
        CryptDestroyHash(hDuplicatedHash);
    if (hCryptProv)
        CryptReleaseContext(hCryptProv, 0);

    return 0;
}