// CryptProtectData.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <windows.h>
#include <stdio.h>

#pragma comment (lib, "Crypt32")

int _tmain(int argc, _TCHAR* argv[])
{
	_tprintf(TEXT(	"======================================================\n= CryptProtectData wrapper by Passcape Software      =\n= Visit http://www.passcape.com for more information =\n======================================================\n\n"));
	if ( argc<3 || argc>5 )
	{
		_tprintf(TEXT("Syntax: %s secret output_filename [entropy_string] [flags]\n"),argv[0]);
		return 1;
	}

	//Declare variables
	DATA_BLOB DataIn;
	DATA_BLOB DataOut;
	DATA_BLOB DataEntropy;
	DWORD dwFlags;
	LPTSTR pFoo;

	//Initialize the structure
	DataOut.pbData=NULL;
	DataOut.cbData=0;
	//
	DataIn.pbData=(LPBYTE)(argv[1]);
	DataIn.cbData=(lstrlen(argv[1])+1) * sizeof(TCHAR) ;
	//
	if ( argc>=4 )
	{
		DataEntropy.pbData=(LPBYTE)(argv[3]);
		DataEntropy.cbData=(lstrlen(argv[3])+1) * sizeof(TCHAR) ;
	}
	//
	if ( argc==5 )
		dwFlags=_tcstoul(argv[4],&pFoo,10);
	else
		dwFlags=0;

	//Protect the secret
	if ( !CryptProtectData(
		&DataIn,
		TEXT("CryptProtectData by Passcape Software"),	//description string to be included
		argc>=4?&DataEntropy:NULL,						//Optional entropy
		NULL,											//reserved
		NULL,											//prompt structure, not used
		dwFlags,										//flags
		&DataOut) )
	{
		dwFlags=GetLastError();
		_tprintf(TEXT("CryptProtectData failed with the following error code: %lu\n"),dwFlags);
		exit(1); 
	}

	//save the output blob
	FILE *f=NULL;
	_tfopen_s(&f,argv[2],TEXT("wb"));
	if ( !f )
	{
		if ( DataOut.pbData )
		{
			LocalFree(DataOut.pbData);
			DataOut.pbData=NULL;
		}
		_tprintf(TEXT("Can't open output file for writing\n"));
		exit(2); 
	}

	//write
	if ( DataOut.pbData )
	{
		size_t written=fwrite(DataOut.pbData,DataOut.cbData,1,f);
		LocalFree(DataOut.pbData);
		DataOut.pbData=NULL;
		if ( written!=1 )
		{
			_tprintf(TEXT("Can't write %lu bytes to output file\n"),DataOut.cbData);
			exit(3);
		}
	}
	
	fclose(f);
	return 0;
}