Clase para cifrar/descifrar en Base64

Como creo que la Seguridad es IMPORTANTE...

Aunque en realidad no existe xDDD

No se quejaran, eh ?

Código:

Option Explicit

' Base64 Encoding/Decoding Algorithm
'
' This algorithms encodes and decodes data into Base64
' format. This format is extremely more efficient than
' Hexadecimal encoding.

Private m_bytIndex(0 To 63) As Byte
Private m_bytReverseIndex(0 To 255) As Byte
Private Const k_bytEqualSign As Byte = 61
Private Const k_bytMask1 As Byte = 3
Private Const k_bytMask2 As Byte = 15
Private Const k_bytMask3 As Byte = 63
Private Const k_bytMask4 As Byte = 192
Private Const k_bytMask5 As Byte = 240
Private Const k_bytMask6 As Byte = 252
Private Const k_bytShift2 As Byte = 4
Private Const k_bytShift4 As Byte = 16
Private Const k_bytShift6 As Byte = 64
Private Const k_lMaxBytesPerLine As Long = 152
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByVal Destination As Long, ByVal Source As Long, ByVal Length As Long)

Public Function Decode64(sInput As String) As String
If sInput = "" Then Exit Function
Decode64 = StrConv(DecodeArray64(sInput), vbUnicode)
End Function

Public Function DecodeArray64(sInput As String) As Byte()
Dim bytInput() As Byte
Dim bytWorkspace() As Byte
Dim bytResult() As Byte
Dim lInputCounter As Long
Dim lWorkspaceCounter As Long

bytInput = Replace(Replace(sInput, vbCrLf, ""), "=", "")
ReDim bytWorkspace(LBound(bytInput) To (UBound(bytInput) * 2)) As Byte
lWorkspaceCounter = LBound(bytWorkspace)
For lInputCounter = LBound(bytInput) To UBound(bytInput)
bytInput(lInputCounter) = m_bytReverseIndex(bytInput(lInputCounter))
Next lInputCounter

For lInputCounter = LBound(bytInput) To (UBound(bytInput) - ((UBound(bytInput) Mod 8) + 8)) Step 8
bytWorkspace(lWorkspaceCounter) = (bytInput(lInputCounter) * k_bytShift2) + (bytInput(lInputCounter + 2) \ k_bytShift4)
bytWorkspace(lWorkspaceCounter + 1) = ((bytInput(lInputCounter + 2) And k_bytMask2) * k_bytShift4) + (bytInput(lInputCounter + 4) \ k_bytShift2)
bytWorkspace(lWorkspaceCounter + 2) = ((bytInput(lInputCounter + 4) And k_bytMask1) * k_bytShift6) + bytInput(lInputCounter + 6)
lWorkspaceCounter = lWorkspaceCounter + 3
Next lInputCounter

Select Case (UBound(bytInput) Mod 8):
Case 3:
bytWorkspace(lWorkspaceCounter) = (bytInput(lInputCounter) * k_bytShift2) + (bytInput(lInputCounter + 2) \ k_bytShift4)
Case 5:
bytWorkspace(lWorkspaceCounter) = (bytInput(lInputCounter) * k_bytShift2) + (bytInput(lInputCounter + 2) \ k_bytShift4)
bytWorkspace(lWorkspaceCounter + 1) = ((bytInput(lInputCounter + 2) And k_bytMask2) * k_bytShift4) + (bytInput(lInputCounter + 4) \ k_bytShift2)
lWorkspaceCounter = lWorkspaceCounter + 1
Case 7:
bytWorkspace(lWorkspaceCounter) = (bytInput(lInputCounter) * k_bytShift2) + (bytInput(lInputCounter + 2) \ k_bytShift4)
bytWorkspace(lWorkspaceCounter + 1) = ((bytInput(lInputCounter + 2) And k_bytMask2) * k_bytShift4) + (bytInput(lInputCounter + 4) \ k_bytShift2)
bytWorkspace(lWorkspaceCounter + 2) = ((bytInput(lInputCounter + 4) And k_bytMask1) * k_bytShift6) + bytInput(lInputCounter + 6)
lWorkspaceCounter = lWorkspaceCounter + 2
End Select

ReDim bytResult(LBound(bytWorkspace) To lWorkspaceCounter) As Byte
If LBound(bytWorkspace) = 0 Then lWorkspaceCounter = lWorkspaceCounter + 1
CopyMemory VarPtr(bytResult(LBound(bytResult))), VarPtr(bytWorkspace(LBound(bytWorkspace))), lWorkspaceCounter
DecodeArray64 = bytResult
End Function

Public Function Encode64(ByRef sInput As String) As String
If sInput = "" Then Exit Function
Dim bytTemp() As Byte
bytTemp = StrConv(sInput, vbFromUnicode)
Encode64 = EncodeArray64(bytTemp)
End Function

Public Function EncodeArray64(ByRef bytInput() As Byte) As String
On Error GoTo ErrorHandler

Dim bytWorkspace() As Byte, bytResult() As Byte
Dim bytCrLf(0 To 3) As Byte, lCounter As Long
Dim lWorkspaceCounter As Long, lLineCounter As Long
Dim lCompleteLines As Long, lBytesRemaining As Long
Dim lpWorkSpace As Long, lpResult As Long
Dim lpCrLf As Long

If UBound(bytInput) < 1024 Then
ReDim bytWorkspace(LBound(bytInput) To (LBound(bytInput) + 4096)) As Byte
Else
ReDim bytWorkspace(LBound(bytInput) To (UBound(bytInput) * 4)) As Byte
End If

lWorkspaceCounter = LBound(bytWorkspace)

For lCounter = LBound(bytInput) To (UBound(bytInput) - ((UBound(bytInput) Mod 3) + 3)) Step 3
bytWorkspace(lWorkspaceCounter) = m_bytIndex((bytInput(lCounter) \ k_bytShift2))
bytWorkspace(lWorkspaceCounter + 2) = m_bytIndex(((bytInput(lCounter) And k_bytMask1) * k_bytShift4) + ((bytInput(lCounter + 1)) \ k_bytShift4))
bytWorkspace(lWorkspaceCounter + 4) = m_bytIndex(((bytInput(lCounter + 1) And k_bytMask2) * k_bytShift2) + (bytInput(lCounter + 2) \ k_bytShift6))
bytWorkspace(lWorkspaceCounter + 6) = m_bytIndex(bytInput(lCounter + 2) And k_bytMask3)
lWorkspaceCounter = lWorkspaceCounter + 8
Next lCounter

Select Case (UBound(bytInput) Mod 3):
Case 0:
bytWorkspace(lWorkspaceCounter) = m_bytIndex((bytInput(lCounter) \ k_bytShift2))
bytWorkspace(lWorkspaceCounter + 2) = m_bytIndex((bytInput(lCounter) And k_bytMask1) * k_bytShift4)
bytWorkspace(lWorkspaceCounter + 4) = k_bytEqualSign
bytWorkspace(lWorkspaceCounter + 6) = k_bytEqualSign
Case 1:
bytWorkspace(lWorkspaceCounter) = m_bytIndex((bytInput(lCounter) \ k_bytShift2))
bytWorkspace(lWorkspaceCounter + 2) = m_bytIndex(((bytInput(lCounter) And k_bytMask1) * k_bytShift4) + ((bytInput(lCounter + 1)) \ k_bytShift4))
bytWorkspace(lWorkspaceCounter + 4) = m_bytIndex((bytInput(lCounter + 1) And k_bytMask2) * k_bytShift2)
bytWorkspace(lWorkspaceCounter + 6) = k_bytEqualSign
Case 2:
bytWorkspace(lWorkspaceCounter) = m_bytIndex((bytInput(lCounter) \ k_bytShift2))
bytWorkspace(lWorkspaceCounter + 2) = m_bytIndex(((bytInput(lCounter) And k_bytMask1) * k_bytShift4) + ((bytInput(lCounter + 1)) \ k_bytShift4))
bytWorkspace(lWorkspaceCounter + 4) = m_bytIndex(((bytInput(lCounter + 1) And k_bytMask2) * k_bytShift2) + ((bytInput(lCounter + 2)) \ k_bytShift6))
bytWorkspace(lWorkspaceCounter + 6) = m_bytIndex(bytInput(lCounter + 2) And k_bytMask3)
End Select

lWorkspaceCounter = lWorkspaceCounter + 8

If lWorkspaceCounter <= k_lMaxBytesPerLine Then
EncodeArray64 = Left$(bytWorkspace, InStr(1, bytWorkspace, Chr$(0)) - 1)
Else
bytCrLf(0) = 13
bytCrLf(1) = 0
bytCrLf(2) = 10
bytCrLf(3) = 0
ReDim bytResult(LBound(bytWorkspace) To UBound(bytWorkspace))
lpWorkSpace = VarPtr(bytWorkspace(LBound(bytWorkspace)))
lpResult = VarPtr(bytResult(LBound(bytResult)))
lpCrLf = VarPtr(bytCrLf(LBound(bytCrLf)))
lCompleteLines = Fix(lWorkspaceCounter / k_lMaxBytesPerLine)

For lLineCounter = 0 To lCompleteLines
CopyMemory lpResult, lpWorkSpace, k_lMaxBytesPerLine
lpWorkSpace = lpWorkSpace + k_lMaxBytesPerLine
lpResult = lpResult + k_lMaxBytesPerLine
CopyMemory lpResult, lpCrLf, 4&
lpResult = lpResult + 4&
Next lLineCounter

lBytesRemaining = lWorkspaceCounter - (lCompleteLines * k_lMaxBytesPerLine)
If lBytesRemaining > 0 Then CopyMemory lpResult, lpWorkSpace, lBytesRemaining
EncodeArray64 = Left$(bytResult, InStr(1, bytResult, Chr$(0)) - 1)
End If
Exit Function

ErrorHandler:
Erase bytResult
EncodeArray64 = bytResult
End Function

Private Sub Class_Initialize()
m_bytIndex(0) = 65 'Asc("A")
m_bytIndex(1) = 66 'Asc("B")
m_bytIndex(2) = 67 'Asc("C")
m_bytIndex(3) = 68 'Asc("D")
m_bytIndex(4) = 69 'Asc("E")
m_bytIndex(5) = 70 'Asc("F")
m_bytIndex(6) = 71 'Asc("G")
m_bytIndex(7) = 72 'Asc("H")
m_bytIndex(8) = 73 'Asc("I")
m_bytIndex(9) = 74 'Asc("J")
m_bytIndex(10) = 75 'Asc("K")
m_bytIndex(11) = 76 'Asc("L")
m_bytIndex(12) = 77 'Asc("M")
m_bytIndex(13) = 78 'Asc("N")
m_bytIndex(14) = 79 'Asc("O")
m_bytIndex(15) = 80 'Asc("P")
m_bytIndex(16) = 81 'Asc("Q")
m_bytIndex(17) = 82 'Asc("R")
m_bytIndex(18) = 83 'Asc("S")
m_bytIndex(19) = 84 'Asc("T")
m_bytIndex(20) = 85 'Asc("U")
m_bytIndex(21) = 86 'Asc("V")
m_bytIndex(22) = 87 'Asc("W")
m_bytIndex(23) = 88 'Asc("X")
m_bytIndex(24) = 89 'Asc("Y")
m_bytIndex(25) = 90 'Asc("Z")
m_bytIndex(26) = 97 'Asc("a")
m_bytIndex(27) = 98 'Asc("b")
m_bytIndex(28) = 99 'Asc("c")
m_bytIndex(29) = 100 'Asc("d")
m_bytIndex(30) = 101 'Asc("e")
m_bytIndex(31) = 102 'Asc("f")
m_bytIndex(32) = 103 'Asc("g")
m_bytIndex(33) = 104 'Asc("h")
m_bytIndex(34) = 105 'Asc("i")
m_bytIndex(35) = 106 'Asc("j")
m_bytIndex(36) = 107 'Asc("k")
m_bytIndex(37) = 108 'Asc("l")
m_bytIndex(38) = 109 'Asc("m")
m_bytIndex(39) = 110 'Asc("n")
m_bytIndex(40) = 111 'Asc("o")
m_bytIndex(41) = 112 'Asc("p")
m_bytIndex(42) = 113 'Asc("q")
m_bytIndex(43) = 114 'Asc("r")
m_bytIndex(44) = 115 'Asc("s")
m_bytIndex(45) = 116 'Asc("t")
m_bytIndex(46) = 117 'Asc("u")
m_bytIndex(47) = 118 'Asc("v")
m_bytIndex(48) = 119 'Asc("w")
m_bytIndex(49) = 120 'Asc("x")
m_bytIndex(50) = 121 'Asc("y")
m_bytIndex(51) = 122 'Asc("z")
m_bytIndex(52) = 48 'Asc("0")
m_bytIndex(53) = 49 'Asc("1")
m_bytIndex(54) = 50 'Asc("2")
m_bytIndex(55) = 51 'Asc("3")
m_bytIndex(56) = 52 'Asc("4")
m_bytIndex(57) = 53 'Asc("5")
m_bytIndex(58) = 54 'Asc("6")
m_bytIndex(59) = 55 'Asc("7")
m_bytIndex(60) = 56 'Asc("8")
m_bytIndex(61) = 57 'Asc("9")
m_bytIndex(62) = 43 'Asc("+")
m_bytIndex(63) = 47 'Asc("/")
m_bytReverseIndex(65) = 0 'Asc("A")
m_bytReverseIndex(66) = 1 'Asc("B")
m_bytReverseIndex(67) = 2 'Asc("C")
m_bytReverseIndex(68) = 3 'Asc("D")
m_bytReverseIndex(69) = 4 'Asc("E")
m_bytReverseIndex(70) = 5 'Asc("F")
m_bytReverseIndex(71) = 6 'Asc("G")
m_bytReverseIndex(72) = 7 'Asc("H")
m_bytReverseIndex(73) = 8 'Asc("I")
m_bytReverseIndex(74) = 9 'Asc("J")
m_bytReverseIndex(75) = 10 'Asc("K")
m_bytReverseIndex(76) = 11 'Asc("L")
m_bytReverseIndex(77) = 12 'Asc("M")
m_bytReverseIndex(78) = 13 'Asc("N")
m_bytReverseIndex(79) = 14 'Asc("O")
m_bytReverseIndex(80) = 15 'Asc("P")
m_bytReverseIndex(81) = 16 'Asc("Q")
m_bytReverseIndex(82) = 17 'Asc("R")
m_bytReverseIndex(83) = 18 'Asc("S")
m_bytReverseIndex(84) = 19 'Asc("T")
m_bytReverseIndex(85) = 20 'Asc("U")
m_bytReverseIndex(86) = 21 'Asc("V")
m_bytReverseIndex(87) = 22 'Asc("W")
m_bytReverseIndex(88) = 23 'Asc("X")
m_bytReverseIndex(89) = 24 'Asc("Y")
m_bytReverseIndex(90) = 25 'Asc("Z")
m_bytReverseIndex(97) = 26 'Asc("a")
m_bytReverseIndex(98) = 27 'Asc("b")
m_bytReverseIndex(99) = 28 'Asc("c")
m_bytReverseIndex(100) = 29 'Asc("d")
m_bytReverseIndex(101) = 30 'Asc("e")
m_bytReverseIndex(102) = 31 'Asc("f")
m_bytReverseIndex(103) = 32 'Asc("g")
m_bytReverseIndex(104) = 33 'Asc("h")
m_bytReverseIndex(105) = 34 'Asc("i")
m_bytReverseIndex(106) = 35 'Asc("j")
m_bytReverseIndex(107) = 36 'Asc("k")
m_bytReverseIndex(108) = 37 'Asc("l")
m_bytReverseIndex(109) = 38 'Asc("m")
m_bytReverseIndex(110) = 39 'Asc("n")
m_bytReverseIndex(111) = 40 'Asc("o")
m_bytReverseIndex(112) = 41 'Asc("p")
m_bytReverseIndex(113) = 42 'Asc("q")
m_bytReverseIndex(114) = 43 'Asc("r")
m_bytReverseIndex(115) = 44 'Asc("s")
m_bytReverseIndex(116) = 45 'Asc("t")
m_bytReverseIndex(117) = 46 'Asc("u")
m_bytReverseIndex(118) = 47 'Asc("v")
m_bytReverseIndex(119) = 48 'Asc("w")
m_bytReverseIndex(120) = 49 'Asc("x")
m_bytReverseIndex(121) = 50 'Asc("y")
m_bytReverseIndex(122) = 51 'Asc("z")
m_bytReverseIndex(48) = 52 'Asc("0")
m_bytReverseIndex(49) = 53 'Asc("1")
m_bytReverseIndex(50) = 54 'Asc("2")
m_bytReverseIndex(51) = 55 'Asc("3")
m_bytReverseIndex(52) = 56 'Asc("4")
m_bytReverseIndex(53) = 57 'Asc("5")
m_bytReverseIndex(54) = 58 'Asc("6")
m_bytReverseIndex(55) = 59 'Asc("7")
m_bytReverseIndex(56) = 60 'Asc("8")
m_bytReverseIndex(57) = 61 'Asc("9")
m_bytReverseIndex(43) = 62 'Asc("+")
m_bytReverseIndex(47) = 63 'Asc("/")
End Sub

Salu2