crypt.h

Vc.Net入门与提高源码

// File: Crypt.h
// Copyright (c) Microsoft Corporation.  All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Classes Reference and related electronic
// documentation provided with the library.
// See these sources for detailed information regarding the
// Microsoft C++ Libraries products.

#pragma once

#include <atlcrypt.h>

inline HRESULT EnsureAcquire(
		CCryptProv& prov,
		LPCTSTR pszContainer = NULL,
		LPCTSTR pszProvider = MS_DEF_PROV,
		DWORD dwProvType = PROV_RSA_FULL,
		DWORD dwFlags = CRYPT_VERIFYCONTEXT | CRYPT_SILENT
		)
{
	HRESULT hr = prov.Initialize(dwProvType, pszContainer, pszProvider , dwFlags);

	if (hr == NTE_KEYSET_NOT_DEF)
			hr = prov.Initialize(dwProvType, pszContainer, pszProvider,  dwFlags | CRYPT_NEWKEYSET);

	return hr;
}

inline HRESULT CreateSaltedHash(
			CCryptProv& Provider,
			const BYTE* Secret, DWORD SecretLength,
			const BYTE* Salt, DWORD SaltLength,
			BYTE* Hash,	DWORD& HashLength
		)
{
	HRESULT hr = E_FAIL;
	HCRYPTHASH hHash = 0;
	if (CryptCreateHash(Provider.GetHandle(), CALG_MD5, 0, 0, &hHash))
	{
		CCryptHash oHash(hHash, TRUE);
		hr = oHash.AddData(Secret, SecretLength);
		if (SUCCEEDED(hr))
		{
			hr = oHash.AddData(Salt, SaltLength);
			if (SUCCEEDED(hr))
			{
				DWORD Size = 0;
				hr = oHash.GetSize(&Size);
				if (SUCCEEDED(hr))
				{
					if (Size <= HashLength)
						hr = oHash.GetValue(Hash, &HashLength);
					else
						hr = E_OUTOFMEMORY;
				}
			}
		}
	}

	return hr;
}

inline HRESULT HashSecret(
			const BYTE* Secret, DWORD SecretLength,
			BYTE* Salt, DWORD& SaltLength,
			BYTE* Hash, DWORD& HashLength
			)
{
	CCryptProv Provider;
	HRESULT hr = EnsureAcquire(Provider);
	if (SUCCEEDED(hr))
	{
		hr = Provider.GenRandom(SaltLength, Salt);
		if (SUCCEEDED(hr))
		{
			hr = CreateSaltedHash( Provider,
					Secret, SecretLength,
					Salt, SaltLength,
					Hash, HashLength);
		}
	}
	return hr;
}

inline HRESULT CompareSecret(
			const BYTE* Secret, DWORD SecretLength,
			const BYTE* Salt, DWORD SaltLength,
			const BYTE* Hash, DWORD HashLength
			)
{
	DWORD CalculatedHashLength = HashLength;
	BYTE* CalculatedHash = new BYTE[HashLength];
	if (!CalculatedHash)
		return E_OUTOFMEMORY;

	CCryptProv Provider;
	HRESULT hr = EnsureAcquire(Provider);
	if (SUCCEEDED(hr))
	{
		hr = CreateSaltedHash( Provider,
				Secret, SecretLength,
				Salt, SaltLength,
				CalculatedHash, CalculatedHashLength);
		if (SUCCEEDED(hr))
		{
			hr = S_FALSE;
			if (CalculatedHashLength == HashLength)
			{
				if (0 == memcmp(Hash, CalculatedHash, HashLength))
					hr = S_OK;
			}
		}
	}
	delete [] CalculatedHash;
	return hr;
}