internal CryptoApiHashProvider(int providerType, int calgHash)
{
SafeProvHandle hProv;
if (!Interop.Advapi32.CryptAcquireContext(out hProv, null, null, providerType, (uint)Interop.Advapi32.CryptAcquireContextFlags.CRYPT_VERIFYCONTEXT))
{
int hr = Marshal.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
SafeHashHandle hHash;
if (!Interop.Advapi32.CryptCreateHash(hProv, calgHash, SafeKeyHandle.InvalidHandle, (int)Interop.Advapi32.CryptCreateHashFlags.None, out hHash))
{
int hr = Marshal.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
int dwHashSize = 0;
int cbHashSize = sizeof(int);
if (!Interop.Advapi32.CryptGetHashParam(hHash, Interop.Advapi32.CryptHashProperty.HP_HASHSIZE, out dwHashSize, ref cbHashSize, 0))
{
int hr = Marshal.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
if (dwHashSize < 0)
{
throw new PlatformNotSupportedException(
SR.Format(
SR.Cryptography_UnknownHashAlgorithm, providerType, calgHash));
}
HashSizeInBytes = dwHashSize;
_calgHash = calgHash;
_hHash = hHash;
_hProv = hProv;
_hHash.SetParent(_hProv);
}
private void SetKey()
{
SafeProvHandle hProv;
if (!Interop.Advapi32.CryptAcquireContext(out hProv, null, null, _providerType, (uint)Interop.Advapi32.CryptAcquireContextFlags.CRYPT_VERIFYCONTEXT))
{
int hr = Interop.CPError.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
int keyHashCalg;
int keyCalg;
GetCalgsFromHMAC(_calgHash, out keyCalg, out keyHashCalg);
SafeKeyHandle hMacKey;
//if key Length longer than sha512 output, we can't derive key just from hash, so need to use simpleblob.
if (_key.Length > 64)
{
ImportLongKeyToCSP(hProv, out hMacKey);
}
else
{
ImportShortKeyToCSP(hProv, keyCalg, keyHashCalg, out hMacKey);
}
//Create Hash with imported Key
SafeHashHandle hMacHash;
if (keyCalg == GostConstants.CALG_GENERIC_SECRET)
{
if (!Interop.Advapi32.CryptCreateHash(hProv, GostConstants.CALG_HMAC, hMacKey, Interop.Advapi32.CryptCreateHashFlags.None, out hMacHash))
{
int hr = Interop.CPError.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
var hmacInfo = new Interop.Advapi32.HMAC_INFO();
hmacInfo.HashAlgid = _calgHash;
if (!Interop.Advapi32.CryptSetHashParam(hMacHash, Interop.Advapi32.CryptHashProperty.HP_HMAC_INFO, hmacInfo.ToByteArray(), 0))
{
int hr = Interop.CPError.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
}
else
{
if (!Interop.Advapi32.CryptCreateHash(hProv, _calgHash, hMacKey, Interop.Advapi32.CryptCreateHashFlags.None, out hMacHash))
{
int hr = Interop.CPError.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
}
_hProv = hProv;
_hKey = hMacKey;
_hHash = hMacHash;
_hHash.SetParent(_hProv);
_hKey.SetParent(_hProv);
}
public override bool TryFinalizeHashAndReset(Span<byte> destination, out int bytesWritten)
{
int hashSize = HashSizeInBytes;
if (!Interop.Advapi32.CryptGetHashParam(_hHash, Interop.Advapi32.CryptHashProperty.HP_HASHVAL, destination, ref hashSize, 0))
{
int hr = Marshal.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
bytesWritten = hashSize;
//reinitialize
_hHash.Dispose();
if (!Interop.Advapi32.CryptCreateHash(_hProv, _calgHash, SafeKeyHandle.InvalidHandle, (int)Interop.Advapi32.CryptCreateHashFlags.None, out _hHash))
{
int hr = Marshal.GetHRForLastWin32Error();
throw new CryptographicException(hr);
}
_hHash.SetParent(_hProv);
return true;
}