AO20CryptoSysWrapper.bas

Attribute VB_Name = "AO20CryptoSysWrapper"
Public Function Encrypt(ByVal hex_key As String, ByVal plain_text As String) As String
    Dim iv() As Byte
    Dim key() As Byte
    Dim plain_text_byte() As Byte
    
    Dim algstr As String
    algstr = "Aes128/CFB/nopad"
    key = cnvBytesFromHexStr(hex_key)
    iv = key
    
    ' "Now is the time for all good men to"
    
    plain_text = cnvHexStrFromString(plain_text)
    plain_text_byte = cnvBytesFromHexStr(plain_text)
    Encrypt = cnvToBase64(cipherEncryptBytes2(plain_text_byte, key, iv, algstr))
   
End Function


Public Function Decrypt(ByVal hex_key As String, ByVal encrypted_text_b64 As String) As String
    Dim iv() As Byte
    Dim key() As Byte
    Dim encrypted_text_byte() As Byte
    Dim decrypted_text() As Byte
    Dim encrypted_text_hex As String
    Dim algstr As String
    algstr = "Aes128/CFB/nopad"
    key = cnvBytesFromHexStr(hex_key)
    iv = key
    
    ' "Now is the time for all good men to"
    
    encrypted_text_byte = cnvFromBase64(encrypted_text_b64)
    encrypted_text_hex = cnvToHex(encrypted_text_byte)
    encrypted_text_byte = cnvBytesFromHexStr(encrypted_text_hex)
    Decrypt = cnvStringFromHexStr(cnvToHex(cipherDecryptBytes2(encrypted_text_byte, key, iv, algstr)))
   
End Function

'HarThaoS: Convierto el str en arr() bytes
Public Function Str2ByteArr(ByVal str As String, ByRef arr() As Byte, Optional ByVal length As Long = 0)
    Dim i As Long
    Dim asd As String
    If length = 0 Then
        ReDim arr(0 To (Len(str) - 1))
        For i = 0 To (Len(str) - 1)
            arr(i) = Asc(Mid(str, i + 1, 1))
        Next i
    Else
        ReDim arr(0 To (length - 1)) As Byte
        For i = 0 To (length - 1)
            arr(i) = Asc(Mid(str, i + 1, 1))
        Next i
    End If
    
End Function

Public Function ByteArr2String(ByRef arr() As Byte) As String
    
    Dim str As String
    Dim i As Long
    For i = 0 To UBound(arr)
        str = str + Chr(arr(i))
    Next i
    
    ByteArr2String = str
    
End Function

Public Function hiByte(ByVal w As Integer) As Byte
    Dim hi As Integer
    If w And &H8000 Then hi = &H4000
    
    hiByte = (w And &H7FFE) \ 256
    hiByte = (hiByte Or (hi \ 128))
    
End Function

Public Function LoByte(w As Integer) As Byte
 LoByte = w And &HFF
End Function