Imports System
Imports System.IO
Imports System.Text
Imports System.Security.Cryptography
Imports Microsoft.VisualBasic
Public Class clsTripleDES
Private Shared key() As Byte = {12, 12, 13, 14, 15, 16, 77, 15, 19, 30, 21, 22, 23, 24, 25, 62, 27, 28, 29, 20, 31, 32, 33, 34}
Private Shared iv() As Byte = {110, 169, 26, 69, 178, 65, 200, 219}
Private Shared encText As New System.Text.UTF8Encoding()
Public Shared Function Encrypt(ByVal strData As String, Optional ByVal Std As Int16 = 0) As String
' Declare a UTF8Encoding object so we may use the GetByte
' method to transform the plainText into a Byte array.
If strData Is Nothing Then
Return Nothing
End If
Dim utf8encoder As UTF8Encoding = New UTF8Encoding()
Dim inputInBytes() As Byte = utf8encoder.GetBytes(strData)
' Create a new TripleDES service provider
Dim tdesProvider As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider()
' The ICryptTransform interface uses the TripleDES
' crypt provider along with encryption key and init vector
' information
Dim cryptoTransform As ICryptoTransform = tdesProvider.CreateEncryptor(key, iv)
' All cryptographic functions need a stream to output the
' encrypted information. Here we declare a memory stream
' for this purpose.
Dim encryptedStream As MemoryStream = New MemoryStream()
Dim cryptStream As CryptoStream = New CryptoStream(encryptedStream, cryptoTransform, CryptoStreamMode.Write)
' Write the encrypted information to the stream. Flush the information
' when done to ensure everything is out of the buffer.
cryptStream.Write(inputInBytes, 0, inputInBytes.Length)
cryptStream.FlushFinalBlock()
encryptedStream.Position = 0
' Read the stream back into a Byte array and return it to the calling
' method.
Dim result(encryptedStream.Length - 1) As Byte
encryptedStream.Read(result, 0, encryptedStream.Length)
cryptStream.Close()
Try
Return Replace(Replace(Replace(Convert.ToBase64String(result), "+", "("), "/", ")"), "=", "-")
Catch
Return ("")
End Try
End Function
Public Shared Function Decrypt(ByVal strData As String, Optional ByVal Std As Int16 = 0) As String
Dim inputInBytes As Byte()
If strData Is Nothing Then
Return Nothing
ElseIf strData.Length < 1 Then
Return Nothing
End If
Try
inputInBytes = Convert.FromBase64String(Replace(Replace(Replace(strData, "(", "+"), ")", "/"), "-", "="))
Catch
Decrypt = ""
Exit Function
End Try
' UTFEncoding is used to transform the decrypted Byte Array
' information back into a string.
Dim utf8encoder As UTF8Encoding = New UTF8Encoding()
Dim tdesProvider As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider()
' As before we must provide the encryption/decryption key along with
' the init vector.
Dim cryptoTransform As ICryptoTransform = tdesProvider.CreateDecryptor(key, iv)
' Provide a memory stream to decrypt information into
Dim decryptedStream As MemoryStream = New MemoryStream()
Dim cryptStream As CryptoStream = New CryptoStream(decryptedStream, cryptoTransform, CryptoStreamMode.Write)
cryptStream.Write(inputInBytes, 0, inputInBytes.Length)
cryptStream.FlushFinalBlock()
decryptedStream.Position = 0
' Read the memory stream and convert it back into a string
Dim result(decryptedStream.Length - 1) As Byte
decryptedStream.Read(result, 0, decryptedStream.Length)
cryptStream.Close()
Dim myutf As UTF8Encoding = New UTF8Encoding()
Return myutf.GetString(result)
End Function
Public Shared Function GenerateHash(ByVal SourceText As String) As String
'Create an encoding object to ensure the encoding standard for the source text
Dim Ue As New UnicodeEncoding()
'Retrieve a byte array based on the source text
Dim ByteSourceText() As Byte = Ue.GetBytes(SourceText)
'Instantiate an MD5 Provider object
Dim Md5 As New MD5CryptoServiceProvider()
'Compute the hash value from the source
Dim ByteHash() As Byte = Md5.ComputeHash(ByteSourceText)
'And convert it to String format for return
Return Convert.ToBase64String(ByteHash)
End Function
End Class
