Librería para calcular hashes y hmacs

[Carloswaldo]

Pues que estoy buscando una librería que calcule hashes y hmacs, la necesito para una aplicación, he encontrado la Librería QuickHash, pero es shareware, necesito algo gratis. Si alguien me ayuda se los agradecería.

[BlackZeroX]

Hash par Archivos:

En un Modulo:

Código (vb) [Seleccionar] Expandir


'---------------------------------------------------------------------------------------
' Module      : mFileHash
' DateTime    : 21/05/2008 06:01
' Author      : Cobein
' Mail        : cobein27@hotmail.com
' WebPage     : http://www.advancevb.com.ar
' Purpose     : API file hash
' Usage       : At your own risk
' Requirements: None
' Distribution: You can freely use this code in your own
'               applications, but you may not reproduce
'               or publish this code on any web site,
'               online service, or distribute as source
'               on any media without express permission.
'
' Reference   : http://www.mvps.org/emorcillo/en/code/vb6/index.shtml
'
' History     : 21/05/2008 First Cut....................................................
'---------------------------------------------------------------------------------------
Option Explicit

Private Const BLOCK_SIZE            As Long = 32 * 1024& ' 32K

Private Const FILE_SHARE_READ       As Long = &H1
Private Const FILE_SHARE_WRITE      As Long = &H2
Private Const GENERIC_READ          As Long = &H80000000
Private Const INVALID_HANDLE_VALUE  As Long = (-1)
Private Const OPEN_EXISTING         As Long = 3

Private Const PROV_RSA_FULL         As Long = 1
Private Const ALG_CLASS_HASH        As Long = 32768
Private Const ALG_TYPE_ANY          As Long = 0
Private Const CRYPT_VERIFYCONTEXT   As Long = &HF0000000

Private Const ALG_SID_MD2           As Long = 1
Private Const ALG_SID_MD4           As Long = 2
Private Const ALG_SID_MD5           As Long = 3
Private Const ALG_SID_SHA1          As Long = 4

Private Const HP_HASHVAL            As Long = 2
Private Const HP_HASHSIZE           As Long = 4

Public Enum HashAlgorithm
   MD2 = ALG_CLASS_HASH Or ALG_TYPE_ANY Or ALG_SID_MD2
   MD4 = ALG_CLASS_HASH Or ALG_TYPE_ANY Or ALG_SID_MD4
   md5 = ALG_CLASS_HASH Or ALG_TYPE_ANY Or ALG_SID_MD5
   SHA1 = ALG_CLASS_HASH Or ALG_TYPE_ANY Or ALG_SID_SHA1
End Enum

Private Type tFileChunks
   bvChunck()                      As Byte
   lChuncks                        As Long
   bvReminder()                    As Byte
   lReminder                       As Long
   lCount                          As Long
End Type

Private Declare Function PathFileExists Lib "shlwapi.dll" Alias "PathFileExistsA" (ByVal pszPath As String) As Long
Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, ByVal lpSecurityAttributes As Any, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, ByVal lpOverlapped As Any) As Long
Private Declare Function GetFileSize Lib "kernel32" (ByVal hFile As Long, lpFileSizeHigh As Long) As Long
Private Declare Function CryptAcquireContext Lib "advapi32.dll" Alias "CryptAcquireContextA" (ByRef phProv As Long, ByVal pszContainer As String, ByVal pszProvider As String, ByVal dwProvType As Long, ByVal dwFlags As Long) As Long
Private Declare Function CryptReleaseContext Lib "advapi32.dll" (ByVal hProv As Long, ByVal dwFlags As Long) As Long
Private Declare Function CryptCreateHash Lib "advapi32.dll" (ByVal hProv As Long, ByVal Algid As Long, ByVal hKey As Long, ByVal dwFlags As Long, ByRef phHash As Long) As Long
Private Declare Function CryptDestroyHash Lib "advapi32.dll" (ByVal hHash As Long) As Long
Private Declare Function CryptHashData Lib "advapi32.dll" (ByVal hHash As Long, pbData As Byte, ByVal dwDataLen As Long, ByVal dwFlags As Long) As Long
Private Declare Function CryptGetHashParam Lib "advapi32.dll" (ByVal hHash As Long, ByVal dwParam As Long, pbData As Any, pdwDataLen As Long, ByVal dwFlags As Long) As Long

Public Function HashFile(ByVal sFile As String, ByVal eHash As HashAlgorithm, ByRef sHash As String) As Long
   Dim lhFile      As Long
   Dim lFileSize   As Long
   Dim lRet        As Long
   Dim lhContext   As Long
   Dim lhHash      As Long
   Dim tFile       As tFileChunks
   Dim lSize       As Long
   
   If Not PathFileExists(sFile) = 0 Then
   
       lhFile = CreateFile(sFile, _
          GENERIC_READ, _
          FILE_SHARE_READ Or FILE_SHARE_WRITE, _
          ByVal 0&, OPEN_EXISTING, 0, 0)
         
       If Not lhFile = INVALID_HANDLE_VALUE Then
       
           lFileSize = GetFileSize(lhFile, 0&)

           If Not lFileSize = 0 Then
           
               lRet = CryptAcquireContext(lhContext, _
                  vbNullString, vbNullString, _
                  PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)
                 
               If Not lRet = 0 Then

                   lRet = CryptCreateHash(lhContext, _
                      eHash, 0, 0, lhHash)
                   
                   If Not lRet = 0 Then
                       
                       With tFile
                           ReDim .bvChunck(1 To BLOCK_SIZE)
                           .lChuncks = lFileSize \ BLOCK_SIZE
                           .lReminder = lFileSize - .lChuncks * BLOCK_SIZE
                           If Not .lReminder = 0 Then
                               ReDim .bvReminder(1 To .lReminder)
                           End If
                           
                           For .lCount = 1 To .lChuncks
                               Call ReadFile(lhFile, .bvChunck(1), BLOCK_SIZE, 0&, 0&)
                               If CryptHashData(lhHash, .bvChunck(1), BLOCK_SIZE, 0) = 0 Then
                                   Exit For
                               End If
                           Next
                           
                           If Not .lReminder = 0 Then
                               Call ReadFile(lhFile, .bvReminder(1), .lReminder, 0&, 0&)
                               lRet = CryptHashData(lhHash, .bvReminder(1), .lReminder, 0)
                           End If
                       
                           lRet = CryptGetHashParam(lhHash, HP_HASHSIZE, lSize, 4, 0)
                           If Not lRet = 0 Then
                               ReDim .bvReminder(0 To lSize - 1)
                               lRet = CryptGetHashParam(lhHash, HP_HASHVAL, .bvReminder(0), lSize, 0)
                               If Not lRet = 0 Then
                                   .lCount = 0
                                   For .lCount = 0 To UBound(.bvReminder)
                                       sHash = sHash & Right$("0" & Hex$(.bvReminder(.lCount)), 2)
                                   Next
                               Else
                                   HashFile = 7
                               End If
                           Else
                               HashFile = 6
                           End If
                       End With
                   Else
                       HashFile = 5
                   End If
               Else
                   HashFile = 4
               End If
           Else
               HashFile = 3
           End If
       Else
           HashFile = 2
       End If
   Else
       HashFile = 1
   End If
   
   Call CryptDestroyHash(lhHash)
   Call CryptReleaseContext(lhContext, 0)
   Call CloseHandle(lhFile)
End Function


Creditos: Cobein.¡1

Hash para Texto (MD5)

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Código (vb) [Seleccionar] Expandir


Option Explicit

Private lngTrack As Long
Private arrLongConversion(4) As Long
Private arrSplit64(63) As Byte

Private Const OFFSET_4 = 4294967296#
Private Const MAXINT_4 = 2147483647



Private Const S11 = 7
Private Const S12 = 12
Private Const S13 = 17
Private Const S14 = 22
Private Const S21 = 5
Private Const S22 = 9
Private Const S23 = 14
Private Const S24 = 20
Private Const S31 = 4
Private Const S32 = 11
Private Const S33 = 16
Private Const S34 = 23
Private Const S41 = 6
Private Const S42 = 10
Private Const S43 = 15
Private Const S44 = 21

Private Function MD5Round(strRound As String, a As Long, _
 b As Long, C As Long, d As Long, X As Long, S As Long, _
 ac As Long) As Long

   Select Case strRound
   
       Case Is = "FF"
           a = MD5LongAdd4(a, (b And C) Or (Not (b) And d), X, ac)
           a = MD5Rotate(a, S)
           a = MD5LongAdd(a, b)
       
       Case Is = "GG"
           a = MD5LongAdd4(a, (b And d) Or (C And Not (d)), X, ac)
           a = MD5Rotate(a, S)
           a = MD5LongAdd(a, b)
           
       Case Is = "HH"
           a = MD5LongAdd4(a, b Xor C Xor d, X, ac)
           a = MD5Rotate(a, S)
           a = MD5LongAdd(a, b)
           
       Case Is = "II"
           a = MD5LongAdd4(a, C Xor (b Or Not (d)), X, ac)
           a = MD5Rotate(a, S)
           a = MD5LongAdd(a, b)
           
   End Select
End Function

Private Function MD5Rotate(lngValue As Long, lngBits As Long) As Long
   Dim lngSign As Long
   Dim lngI As Long
   
   lngBits = (lngBits Mod 32)
   
   If lngBits = 0 Then MD5Rotate = lngValue: Exit Function
   
   For lngI = 1 To lngBits
       lngSign = lngValue And &HC0000000
       lngValue = (lngValue And &H3FFFFFFF) * 2
       lngValue = lngValue Or ((lngSign < 0) And 1) Or _
           (CBool(lngSign And &H40000000) And &H80000000)
   Next
   
   MD5Rotate = lngValue
End Function

Private Function TRID() As String
   Dim sngNum As Single, lngnum As Long
   Dim strResult As String
 
   sngNum = Rnd(2147483648#)
   strResult = CStr(sngNum)
   
   strResult = Replace(strResult, "0.", "")
   strResult = Replace(strResult, ".", "")
   strResult = Replace(strResult, "E-", "")
   
   TRID = strResult
End Function

Private Function MD564Split(lngLength As Long, bytBuffer() As Byte) As String
   Dim lngBytesTotal As Long, lngBytesToAdd As Long
   Dim intLoop As Integer, intLoop2 As Integer, lngTrace As Long
   Dim intInnerLoop As Integer, intLoop3 As Integer
   
   lngBytesTotal = lngTrack Mod 64
   lngBytesToAdd = 64 - lngBytesTotal
   lngTrack = (lngTrack + lngLength)
   
   If lngLength >= lngBytesToAdd Then
       For intLoop = 0 To lngBytesToAdd - 1
           arrSplit64(lngBytesTotal + intLoop) = bytBuffer(intLoop)
       Next intLoop
       
       MD5Conversion arrSplit64
       
       lngTrace = (lngLength) Mod 64

       For intLoop2 = lngBytesToAdd To lngLength - intLoop - lngTrace Step 64
           For intInnerLoop = 0 To 63
               arrSplit64(intInnerLoop) = bytBuffer(intLoop2 + intInnerLoop)
           Next intInnerLoop
           
           MD5Conversion arrSplit64
       
       Next intLoop2
       
       lngBytesTotal = 0
   Else
   
     intLoop2 = 0
   
   End If
   
   For intLoop3 = 0 To lngLength - intLoop2 - 1
       
       arrSplit64(lngBytesTotal + intLoop3) = bytBuffer(intLoop2 + intLoop3)
   
   Next intLoop3
End Function

Private Function MD5StringArray(strInput As String) As Byte()
   Dim intLoop As Integer
   Dim bytBuffer() As Byte
   ReDim bytBuffer(Len(strInput))
   
   For intLoop = 0 To Len(strInput) - 1
       bytBuffer(intLoop) = Asc(Mid(strInput, intLoop + 1, 1))
   Next intLoop
   
   MD5StringArray = bytBuffer
End Function

Private Sub MD5Conversion(bytBuffer() As Byte)
   Dim X(16) As Long, a As Long
   Dim b As Long, C As Long
   Dim d As Long
   
   a = arrLongConversion(1)
   b = arrLongConversion(2)
   C = arrLongConversion(3)
   d = arrLongConversion(4)
   
   MD5Decode 64, X, bytBuffer
   
   MD5Round "FF", a, b, C, d, X(0), S11, -680876936
   MD5Round "FF", d, a, b, C, X(1), S12, -389564586
   MD5Round "FF", C, d, a, b, X(2), S13, 606105819
   MD5Round "FF", b, C, d, a, X(3), S14, -1044525330
   MD5Round "FF", a, b, C, d, X(4), S11, -176418897
   MD5Round "FF", d, a, b, C, X(5), S12, 1200080426
   MD5Round "FF", C, d, a, b, X(6), S13, -1473231341
   MD5Round "FF", b, C, d, a, X(7), S14, -45705983
   MD5Round "FF", a, b, C, d, X(8), S11, 1770035416
   MD5Round "FF", d, a, b, C, X(9), S12, -1958414417
   MD5Round "FF", C, d, a, b, X(10), S13, -42063
   MD5Round "FF", b, C, d, a, X(11), S14, -1990404162
   MD5Round "FF", a, b, C, d, X(12), S11, 1804603682
   MD5Round "FF", d, a, b, C, X(13), S12, -40341101
   MD5Round "FF", C, d, a, b, X(14), S13, -1502002290
   MD5Round "FF", b, C, d, a, X(15), S14, 1236535329

   MD5Round "GG", a, b, C, d, X(1), S21, -165796510
   MD5Round "GG", d, a, b, C, X(6), S22, -1069501632
   MD5Round "GG", C, d, a, b, X(11), S23, 643717713
   MD5Round "GG", b, C, d, a, X(0), S24, -373897302
   MD5Round "GG", a, b, C, d, X(5), S21, -701558691
   MD5Round "GG", d, a, b, C, X(10), S22, 38016083
   MD5Round "GG", C, d, a, b, X(15), S23, -660478335
   MD5Round "GG", b, C, d, a, X(4), S24, -405537848
   MD5Round "GG", a, b, C, d, X(9), S21, 568446438
   MD5Round "GG", d, a, b, C, X(14), S22, -1019803690
   MD5Round "GG", C, d, a, b, X(3), S23, -187363961
   MD5Round "GG", b, C, d, a, X(8), S24, 1163531501
   MD5Round "GG", a, b, C, d, X(13), S21, -1444681467
   MD5Round "GG", d, a, b, C, X(2), S22, -51403784
   MD5Round "GG", C, d, a, b, X(7), S23, 1735328473
   MD5Round "GG", b, C, d, a, X(12), S24, -1926607734
 
   MD5Round "HH", a, b, C, d, X(5), S31, -378558
   MD5Round "HH", d, a, b, C, X(8), S32, -2022574463
   MD5Round "HH", C, d, a, b, X(11), S33, 1839030562
   MD5Round "HH", b, C, d, a, X(14), S34, -35309556
   MD5Round "HH", a, b, C, d, X(1), S31, -1530992060
   MD5Round "HH", d, a, b, C, X(4), S32, 1272893353
   MD5Round "HH", C, d, a, b, X(7), S33, -155497632
   MD5Round "HH", b, C, d, a, X(10), S34, -1094730640
   MD5Round "HH", a, b, C, d, X(13), S31, 681279174
   MD5Round "HH", d, a, b, C, X(0), S32, -358537222
   MD5Round "HH", C, d, a, b, X(3), S33, -722521979
   MD5Round "HH", b, C, d, a, X(6), S34, 76029189
   MD5Round "HH", a, b, C, d, X(9), S31, -640364487
   MD5Round "HH", d, a, b, C, X(12), S32, -421815835
   MD5Round "HH", C, d, a, b, X(15), S33, 530742520
   MD5Round "HH", b, C, d, a, X(2), S34, -995338651

   MD5Round "II", a, b, C, d, X(0), S41, -198630844
   MD5Round "II", d, a, b, C, X(7), S42, 1126891415
   MD5Round "II", C, d, a, b, X(14), S43, -1416354905
   MD5Round "II", b, C, d, a, X(5), S44, -57434055
   MD5Round "II", a, b, C, d, X(12), S41, 1700485571
   MD5Round "II", d, a, b, C, X(3), S42, -1894986606
   MD5Round "II", C, d, a, b, X(10), S43, -1051523
   MD5Round "II", b, C, d, a, X(1), S44, -2054922799
   MD5Round "II", a, b, C, d, X(8), S41, 1873313359
   MD5Round "II", d, a, b, C, X(15), S42, -30611744
   MD5Round "II", C, d, a, b, X(6), S43, -1560198380
   MD5Round "II", b, C, d, a, X(13), S44, 1309151649
   MD5Round "II", a, b, C, d, X(4), S41, -145523070
   MD5Round "II", d, a, b, C, X(11), S42, -1120210379
   MD5Round "II", C, d, a, b, X(2), S43, 718787259
   MD5Round "II", b, C, d, a, X(9), S44, -343485551
   
   arrLongConversion(1) = MD5LongAdd(arrLongConversion(1), a)
   arrLongConversion(2) = MD5LongAdd(arrLongConversion(2), b)
   arrLongConversion(3) = MD5LongAdd(arrLongConversion(3), C)
   arrLongConversion(4) = MD5LongAdd(arrLongConversion(4), d)
End Sub

Private Function MD5LongAdd(lngVal1 As Long, lngVal2 As Long) As Long
   Dim lngHighWord As Long
   Dim lngLowWord As Long
   Dim lngOverflow As Long

   lngLowWord = (lngVal1 And &HFFFF&) + (lngVal2 And &HFFFF&)
   
   lngOverflow = lngLowWord \ 65536
   
   lngHighWord = (((lngVal1 And &HFFFF0000) \ 65536) _
       + ((lngVal2 And &HFFFF0000) \ 65536) _
       + lngOverflow) And &HFFFF&
   
   MD5LongAdd = MD5LongConversion((lngHighWord * 65536#) _
       + (lngLowWord And &HFFFF&))
End Function

Private Function MD5LongAdd4(lngVal1 As Long, _
 lngVal2 As Long, lngVal3 As Long, lngVal4 As Long) As Long
   Dim lngHighWord As Long
   Dim lngLowWord As Long
   Dim lngOverflow As Long

   lngLowWord = (lngVal1 And &HFFFF&) _
       + (lngVal2 And &HFFFF&) _
       + (lngVal3 And &HFFFF&) _
       + (lngVal4 And &HFFFF&)
   
   lngOverflow = lngLowWord \ 65536
   
   lngHighWord = (((lngVal1 And &HFFFF0000) \ 65536) _
       + ((lngVal2 And &HFFFF0000) \ 65536) _
       + ((lngVal3 And &HFFFF0000) \ 65536) _
       + ((lngVal4 And &HFFFF0000) \ 65536) _
       + lngOverflow) And &HFFFF&
   
   MD5LongAdd4 = MD5LongConversion((lngHighWord * 65536#) _
       + (lngLowWord And &HFFFF&))
End Function

Private Sub MD5Decode(intLength As Integer, _
 lngOutBuffer() As Long, bytInBuffer() As Byte)
   Dim intDblIndex As Integer
   Dim intByteIndex As Integer
   Dim dblSum As Double
   
   intDblIndex = 0
   
   For intByteIndex = 0 To intLength - 1 Step 4
       
       dblSum = bytInBuffer(intByteIndex) + bytInBuffer(intByteIndex + 1) _
           * 256# + bytInBuffer(intByteIndex + 2) _
           * 65536# + bytInBuffer(intByteIndex + 3) * 16777216#
       lngOutBuffer(intDblIndex) = MD5LongConversion(dblSum)
       intDblIndex = (intDblIndex + 1)
   
   Next intByteIndex
End Sub

Private Function MD5LongConversion(dblValue As Double) As Long
   If dblValue < 0 Or dblValue >= OFFSET_4 Then Error 6
       
   If dblValue <= MAXINT_4 Then
       MD5LongConversion = dblValue
   Else
       MD5LongConversion = dblValue - OFFSET_4
   End If
End Function

Private Sub MD5Finish()
   Dim dblBits As Double
   Dim arrPadding(72) As Byte
   Dim lngBytesBuffered As Long
   
   arrPadding(0) = &H80
   
   dblBits = lngTrack * 8
   
   lngBytesBuffered = lngTrack Mod 64
   
   If lngBytesBuffered <= 56 Then
       MD564Split (56 - lngBytesBuffered), arrPadding
   Else
       MD564Split (120 - lngTrack), arrPadding
   End If
   
   arrPadding(0) = MD5LongConversion(dblBits) And &HFF&
   arrPadding(1) = MD5LongConversion(dblBits) \ 256 And &HFF&
   arrPadding(2) = MD5LongConversion(dblBits) \ 65536 And &HFF&
   arrPadding(3) = MD5LongConversion(dblBits) \ 16777216 And &HFF&
   arrPadding(4) = 0
   arrPadding(5) = 0
   arrPadding(6) = 0
   arrPadding(7) = 0
   
   MD564Split 8, arrPadding
End Sub

Private Function MD5StringChange(lngnum As Long) As String
   Dim bytA As Byte
   Dim bytB As Byte
   Dim bytC As Byte
   Dim bytD As Byte
       
       bytA = lngnum And &HFF&
       If bytA < 16 Then
           MD5StringChange = "0" & Hex(bytA)
       Else
           MD5StringChange = Hex(bytA)
       End If
             
       bytB = (lngnum And &HFF00&) \ 256
       If bytB < 16 Then
           MD5StringChange = MD5StringChange & "0" & Hex(bytB)
       Else
           MD5StringChange = MD5StringChange & Hex(bytB)
       End If
       
       bytC = (lngnum And &HFF0000) \ 65536
       If bytC < 16 Then
           MD5StringChange = MD5StringChange & "0" & Hex(bytC)
       Else
           MD5StringChange = MD5StringChange & Hex(bytC)
       End If
     
       If lngnum < 0 Then
           bytD = ((lngnum And &H7F000000) \ 16777216) Or &H80&
       Else
           bytD = (lngnum And &HFF000000) \ 16777216
       End If
       
       If bytD < 16 Then
           MD5StringChange = MD5StringChange & "0" & Hex(bytD)
       Else
           MD5StringChange = MD5StringChange & Hex(bytD)
       End If
End Function

Private Function MD5Value() As String

   MD5Value = LCase(MD5StringChange(arrLongConversion(1)) & _
       MD5StringChange(arrLongConversion(2)) & _
       MD5StringChange(arrLongConversion(3)) & _
       MD5StringChange(arrLongConversion(4)))
End Function

Public Function CalculateMD5(strMessage As String) As String
   Dim bytBuffer() As Byte
   
   bytBuffer = MD5StringArray(strMessage)
   
   MD5Start
   MD564Split Len(strMessage), bytBuffer
   MD5Finish
   
   CalculateMD5 = MD5Value
End Function

Private Sub MD5Start()
   lngTrack = 0
   arrLongConversion(1) = MD5LongConversion(1732584193#)
   arrLongConversion(2) = MD5LongConversion(4023233417#)
   arrLongConversion(3) = MD5LongConversion(2562383102#)
   arrLongConversion(4) = MD5LongConversion(271733878#)
End Sub


Con el modulo anterior en un Formualrio:

Código (vb) [Seleccionar] Expandir


Private Sub Command1_Click()
    Text2.Text = CalculateMD5(Text1.Text)
End Sub


De este ultimo desconozco los creditos...
Dulces Lunas

[Carloswaldo]

Gracias!

Pero lo que ahora necesito es algo para calcular hmacs.

http://en.wikipedia.org/wiki/HMAC

De hecho ahí mismo hay un pseudocódigo de cómo se podría hacer una implementación:

Código [Seleccionar] Expandir

function hmac (key, message)
    opad = [0x5c * blocksize] // Where blocksize is that of the underlying hash function
    ipad = [0x36 * blocksize]

    if (length(key) > blocksize) then
        key = hash(key) // keys longer than blocksize are shortened
    end if

    for i from 0 to length(key) - 1 step 1
        ipad[i] = ipad[i] ⊕ key[i] // Where ⊕ is exclusive or (XOR)
        opad[i] = opad[i] ⊕ key[i]
    end for

    return hash(opad ++ hash(ipad ++ message)) // Where ++ is concatenation
end function


Lo que pasa es que no entiendo nada. xD ¿Se puede pasar ese código a vb6?