Click here to Skip to main content
13,140,613 members (44,923 online)
Click here to Skip to main content

Stats

191.5K views
5.2K downloads
114 bookmarked
Posted 15 Dec 2006

A File Checksum Shell Menu Extension DLL

, 23 May 2008
Create a File Checksum Shell Menu Extension using ATL and Crypto++
CtxCreateHash
CtxCreateHash
CreateHash.rgs
CtxCreateHash.def
CtxCreateHash.rgs
CtxCreateHash.vcproj.8.00.old
CtxCreateHashps.def
CtxCreateHashPS.vcproj.8.00.old
CtxCreateHash.sln.old
CreateHash.rgs
CtxCreateHash.aps
CtxCreateHash.def
CtxCreateHash.rgs
CtxCreateHashps.def
CtxCreateHash.dll
CtxVerifyHash
CtxVerifyHash
CtxVerifyHash.def
CtxVerifyHash.rgs
CtxVerifyHash.vcproj.8.00.old
CtxVerifyHashps.def
CtxVerifyHashPS.vcproj.8.00.old
VerifyHash.rgs
CtxVerifyHash.sln.old
CtxVerifyHash.aps
CtxVerifyHash.def
CtxVerifyHash.rgs
CtxVerifyHashps.def
VerifyHash.rgs
CtxVerifyHash.dll
Sample 1
Test 1.dsp
Test 1.dsw
Sample 2
Test 2.dsp
Test 2.dsw
Sample 3
Test 3.dsp
Test 3.dsw
Sample 4
Test 4.dsp
Test 4.dsw
Sample 5
CtxTest.def
CtxTest.dsp
CtxTest.dsw
CtxTestps.def
CtxTestps.mk
MenuItem.rgs
// CreateHash.cpp : Implementation of CCreateHash

#include "stdafx.h"
#include "CreateHash.h"


// CCreateHash
/////////////////////////////////////////////////////////////////////////////
// CCreateHash
#pragma warning ( push, 4 )

HRESULT CCreateHash::InvokeCommand ( LPCMINVOKECOMMANDINFO pCmdInfo )
{
    unsigned int i = 0, j = 0;

    // Friendly Name: 'MD5'
    std::vector< std::wstring > hashnames;    
    
    // Hash: 47FD4214F5775826FB20FEC1091987A1 
    std::vector< std::wstring > hashvalues;

    std::wstring ClipboardText;
    std::wstring MsgBoxMessage;

    MsgBoxMessage = L"The following was placed on the Windows Clipboard:\r\n\r\n";

    // If lpVerb really points to a std::string,
    //   ignore this function call and bail out.
    if ( 0 != HIWORD( pCmdInfo->lpVerb ) ) { return E_INVALIDARG; }

    // Get the command index - the only valid one is 0.
    switch( LOWORD( pCmdInfo->lpVerb ) )
    {
        case 0:
        {
            for( i = 0; i < files.size(); i++ )
            {
                CalculateFileHashes( files[ i ], hashnames, hashvalues );

                ClipboardText += FileName( files[ i ] ) + L"\r\n";
                MsgBoxMessage += FileName( files[ i ] ) + L"\r\n";

                for( j = 0; j < hashvalues.size(); j++ )
                {
                    // Clipboard Text is easy...
                    //   Just dump the information
                    ClipboardText += hashnames[ j ] + L": " + hashvalues[ j ] + L"\r\n";

                    // Keep the Message Box reasonable
                    if( files.size() <= 2 )
                    {
                        // Less than 2 files - Dump everything
                        //   inot the MessageBox
                        MsgBoxMessage += L"    ";
                        MsgBoxMessage += hashnames[ j ] + L": ";
                        MsgBoxMessage += Snip( hashvalues[ j ] ) + L"\r\n";
                    }
                    else
                    {                        
                        if( 0 == i || 1 == i )
                        {
                            // The first two get a full print...
                            MsgBoxMessage += L"    ";
                            MsgBoxMessage += hashnames[ j ] + L": ";
                            MsgBoxMessage += Snip( hashvalues[ j ] ) + L"\r\n";

                        }
                        else
                        if( 0 == j )
                        {
                            MsgBoxMessage += L"    ...\r\n";
                        }
                    }
                    // End - Keep the Message Box reasonable
                    
                } // for( j = 0; j < hashnames.size(); j++ )

                // Pretty Print
                if( i + 1 < files.size() )
                {
                    ClipboardText += L"\r\n";
                    if( files.size() <= 2 )
                    {
                        MsgBoxMessage += L"\r\n";
                    }
                }

            } // for( i = 0; i < files.size(); i++ )

            SetClipboardText( pCmdInfo->hwnd, ClipboardText );

            #ifdef _UNICODE
              MessageBox( pCmdInfo->hwnd, MsgBoxMessage.c_str(),
                          _T("File Checksum Results"), MB_ICONINFORMATION );
            #else
              MessageBox( pCmdInfo->hwnd, StringNarrow( MsgBoxMessage ).c_str(),
                          _T("File Checksum Results"), MB_ICONINFORMATION );
            #endif            

            return S_OK;

            break;
        }
     
        case 1:
        {
            assert( false );
            break;
        }

        default:            
            break;
    }

    return E_INVALIDARG;
}

HRESULT CCreateHash::GetCommandString( UINT idCmd, UINT uFlags,
                     UINT* pwReserved, LPSTR pszName, UINT cchMax )
{
    pwReserved;         // Warning C4100 suppression

    // Check idCmd, it must be 0 since we have only one menu item.
    if ( 0 != idCmd ) { return E_INVALIDARG; }
 
    // If Explorer is asking for a help std::string, copy our std::string
    //   into the supplied buffer.
    if( uFlags & GCS_HELPTEXT )
    {
        if ( uFlags & GCS_UNICODE )
        {
            LPCWSTR szText = L"File Checksum Extension by Jeffrey Walton";
            // We need to cast pszName to a Unicode std::string, and then use the
            // Unicode std::string copy API.
            lstrcpynW ( reinterpret_cast<LPWSTR>( pszName ), szText, cchMax );
        }
        else
        {
            LPCSTR szText = "File Checksum Extension by Jeffrey Walton";
            // Use the ANSI std::string copy API to return the help std::string.
            lstrcpynA ( pszName, szText, cchMax );
        }

        return S_OK;
    }

    return E_INVALIDARG;
}

HRESULT CCreateHash::QueryContextMenu( HMENU hmenu, UINT uMenuIndex,
                       UINT uidFirstCmd, UINT uidLastCmd, UINT uFlags )
{   
    uidFirstCmd;        // Warning C4100 suppression
    uidLastCmd;         // Warning C4100 suppression

    // If the flags include CMF_DEFAULTONLY then we shouldn't do anything.
    if( uFlags & CMF_DEFAULTONLY )
        { return MAKE_HRESULT ( SEVERITY_SUCCESS, FACILITY_NULL, 0 ); }

    if( files.size() > 1 )
    {
        InsertMenu( hmenu, uMenuIndex, MF_BYPOSITION,
                    uidFirstCmd, _T("Create Checksums") );
    }
    else
    {
        InsertMenu( hmenu, uMenuIndex, MF_BYPOSITION,
                    uidFirstCmd, _T("Create Checksum") );
    }

    return MAKE_HRESULT( SEVERITY_SUCCESS, FACILITY_NULL, 1 );
}

STDMETHODIMP CCreateHash::Initialize( LPCITEMIDLIST pidlFolder,
                                      LPDATAOBJECT pDataObj, HKEY hProgID )
{
    pidlFolder;     // Warning C4100 suppression
    hProgID;        // Warning C4100 suppression

    FORMATETC fmt = { CF_HDROP, NULL, DVASPECT_CONTENT, -1, TYMED_HGLOBAL };
    STGMEDIUM stg = { TYMED_HGLOBAL };
    HDROP     hDrop;

    // Look for CF_HDROP data in the data object. If there
    // is no such data, return an error back to Explorer.
    if( FAILED( pDataObj->GetData ( &fmt, &stg ) ))
        { return E_INVALIDARG; }

    // Get a pointer to the actual data.
    hDrop = static_cast<HDROP>( GlobalLock ( stg.hGlobal ) );

    // Make sure it worked.
    if( NULL == hDrop )
        { return E_INVALIDARG; }

    // Sanity check - make sure there is at least one filename.
    UINT uNumFiles = DragQueryFile( hDrop, static_cast<UINT>(-1), NULL, 0 );    
    if( 0 == uNumFiles )
    {
        GlobalUnlock ( stg.hGlobal );
        ReleaseStgMedium ( &stg );

        return E_INVALIDARG;
    }

    HRESULT hr = S_OK;

    // The author has encountered situations where
    //   MAX_PATH*2 was a bit too small...
    TCHAR file[ MAX_PATH * 4 + 1 ];
    // Loop through all the files that were selected.
    for(UINT i = 0; i < uNumFiles; i++)
    {
        DragQueryFile( static_cast<HDROP>( stg.hGlobal ), i, file, MAX_PATH * 4 );

        // If the file name is a directory, silently skip
        //   We should not encounter this...
        if (::GetFileAttributes( file ) & FILE_ATTRIBUTE_DIRECTORY)
            { continue; }

        // Add the file name to the end of the list.
        #ifdef UNICODE
          files.push_back( file );
        #else
          files.push_back( StringWiden( file ) );
        #endif
    }

    std::sort( files.begin(), files.end() );

    GlobalUnlock ( stg.hGlobal );
    ReleaseStgMedium ( &stg );

    return hr;
}

bool CCreateHash::CalculateFileHashes( const std::wstring& filename,
                                       std::vector< std::wstring >& hashnames,
                                       std::vector< std::wstring >& hashvalues )
{
    CryptoPP::MD5  hashMD5;
    CryptoPP::HashFilter filterMD5(hashMD5);

    CryptoPP::SHA1 hashSHA1;
    CryptoPP::HashFilter filterSHA1(hashSHA1);

    CryptoPP::SHA256 hashSHA256;
    CryptoPP::HashFilter filterSHA256(hashSHA256);

    CryptoPP::SHA512 hashSHA512;
    CryptoPP::HashFilter filterSHA512(hashSHA512);

    CryptoPP::Whirlpool hashWhirlpool;
    CryptoPP::HashFilter filterWhirlpool(hashWhirlpool);

    std::auto_ptr<CryptoPP::ChannelSwitch>
                  channelSwitch(new CryptoPP::ChannelSwitch);
 
    channelSwitch->AddDefaultRoute(filterMD5);
    channelSwitch->AddDefaultRoute(filterSHA1);
    channelSwitch->AddDefaultRoute(filterSHA256);
    channelSwitch->AddDefaultRoute(filterSHA512);
    channelSwitch->AddDefaultRoute(filterWhirlpool);

    try {
        CryptoPP::FileSource( StringNarrow( filename ).c_str(),
                              true, channelSwitch.release() );
    }

    catch( CryptoPP::Exception& e ) { e; return false; }   // e.what()
    catch( std::exception& e )      { e; return false; }   // e.what()
    catch( ... )                    {    return false; }
    
    std::string digest;
    CryptoPP::HexEncoder encoder( new CryptoPP::StringSink( digest ),
                                  true /* uppercase */ ); 

    hashnames.clear(); hashvalues.clear();

    filterMD5.TransferTo( encoder );
    hashnames.push_back( StringWiden( filterMD5.AlgorithmName() ) );
    hashvalues.push_back( StringWiden( digest ) );
    digest.erase();

    filterSHA1.TransferTo( encoder );
    hashnames.push_back( StringWiden( filterSHA1.AlgorithmName() ) );
    hashvalues.push_back( StringWiden( digest ) );
    digest.erase();

    filterSHA256.TransferTo( encoder );
    hashnames.push_back( StringWiden( filterSHA256.AlgorithmName() ) );
    hashvalues.push_back( StringWiden( digest ) );
    digest.erase();

    filterSHA512.TransferTo( encoder );
    hashnames.push_back( StringWiden( filterSHA512.AlgorithmName() ) );
    hashvalues.push_back( StringWiden( digest ) );
    digest.erase();

    filterWhirlpool.TransferTo( encoder );
    hashnames.push_back( StringWiden( filterWhirlpool.AlgorithmName() ) );
    hashvalues.push_back( StringWiden( digest ) );
    digest.erase();

    return true;
}

std::string CCreateHash::FileName( const std::string& file )
{
    std::string filename = file;

    std::string::size_type pos = file.find_last_of( "\\" );

    if( std::string::npos != pos )
    {
        if( pos <= file.length() )
            { filename = file.substr( pos + 1 ); }
    }

    return filename;
}

std::wstring CCreateHash::FileName( const std::wstring& file )
{
    std::wstring filename = file;

    std::wstring::size_type pos = file.find_last_of( L"\\" );

    if( std::string::npos != pos )
    {
        if( pos <= file.length() )
            { filename = file.substr( pos + 1 ); }
    }

    return filename;
}

bool CCreateHash::SetClipboardText( HWND hwnd, const std::wstring& text )
{
    // Prepare Clipboard
    if( FALSE != OpenClipboard( hwnd ) ) 
    {
        EmptyClipboard();
        CloseClipboard();
    }

    #ifdef UNICODE
      return SetClipboardTextWide( hwnd, text );
    #else
      return SetClipboardTextNarrow( hwnd, StringNarrow( text ) );
    #endif
}

bool CCreateHash::SetClipboardText( HWND hwnd, const std::string& text )
{
    // Prepare Clipboard
    if( FALSE != OpenClipboard( hwnd ) ) 
    {
        EmptyClipboard();
        CloseClipboard();
    }

    #ifdef UNICODE
      return SetClipboardTextWide( hwnd, StringWiden( text ) );
    #else
      return SetClipboardTextNarrow( hwnd, text );
    #endif
}

bool CCreateHash::SetClipboardTextWide( HWND hwnd, const std::wstring& text )
{
    HGLOBAL hClipboardText = NULL;
 
    // Open the clipboard
    if( FALSE == OpenClipboard( hwnd ) ) 
        { return false; }
 
    // Allocate memory for the text
    hClipboardText = GlobalAlloc(GMEM_DDESHARE,
                                (text.length() + 1) * sizeof( wchar_t ) ); 


    if( NULL == hClipboardText ) 
    { 
        CloseClipboard(); 
        return false; 
    }

    wchar_t* pText = static_cast<wchar_t*>( GlobalLock( hClipboardText ) );

    try
    {
        memcpy( pText, text.c_str(), text.length() * sizeof( wchar_t ) );

        // Assure NULL termination
        pText[ text.length() ] = L'\0';
    }

    catch( ... )
    {
        CloseClipboard();
 
        return false;
    }

    GlobalUnlock( hClipboardText );

    // Place the text on the clipboard. 
    bool result = ( FALSE != SetClipboardData( CF_UNICODETEXT, hClipboardText ) );

    CloseClipboard();

    return result;
}

bool CCreateHash::SetClipboardTextNarrow( HWND hwnd, const std::string& text )
{
    HGLOBAL hClipboardText = NULL;
 
    // Open the clipboard
    if( FALSE == OpenClipboard( hwnd ) ) 
        { return false; }
 
    // Allocate memory for the text
    hClipboardText = GlobalAlloc(GMEM_DDESHARE,
                                (text.length() + 1) * sizeof( char ) ); 

    // Sanity check
    if( NULL == hClipboardText ) 
    { 
        CloseClipboard(); 
        return false; 
    }

    char* pText = static_cast<char*>( GlobalLock( hClipboardText ) );

    try
    {
        memcpy( pText, text.c_str(), text.length() * sizeof( char* ) );

        // Assure NULL termination
        pText[ text.length() ] = '\0';
    }

    catch( ... )
    {
        CloseClipboard();
 
        return false;
    }

    GlobalUnlock( hClipboardText );

    // Place the text on the clipboard. 
    bool result = ( FALSE != SetClipboardData( CF_TEXT, hClipboardText ) );

    CloseClipboard();

    return result;
}

std::wstring CCreateHash::Snip( const std::wstring& hash )
{
    const unsigned int SIZE = 32;
    std::wstring result;
    
    if( hash.length() < SIZE + 4 ) { return hash; }

    result  = hash.substr( 0, SIZE/2 );
    result += L"...";
    result += hash.substr( hash.length() - SIZE/2 );

    return result;
}

#pragma warning( pop )

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The GNU Lesser General Public License (LGPLv3)

Share

About the Author

Jeffrey Walton
Systems / Hardware Administrator
United States United States
No Biography provided

You may also be interested in...

Permalink | Advertise | Privacy | Terms of Use | Mobile
Web01 | 2.8.170915.1 | Last Updated 24 May 2008
Article Copyright 2006 by Jeffrey Walton
Everything else Copyright © CodeProject, 1999-2017
Layout: fixed | fluid