78 lines
2.8 KiB
VB.net
78 lines
2.8 KiB
VB.net
Imports System.Security.Cryptography
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Imports NLog
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Imports DigitalData.Modules.Logging
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Public Class clsEncryption
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Private TripleDes As New TripleDESCryptoServiceProvider
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Private Logger As Modules.Logging.Logger
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Sub New(ByVal key As String, LogConf As LogConfig)
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Logger = LogConf.GetLogger
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' Initialize the crypto provider.
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TripleDes.Key = TruncateHash(key, TripleDes.KeySize \ 8)
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TripleDes.IV = TruncateHash("", TripleDes.BlockSize \ 8)
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End Sub
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Private Function TruncateHash(
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ByVal key As String,
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ByVal length As Integer) As Byte()
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Dim sha1 As New SHA1CryptoServiceProvider
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' Hash the key.
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Dim keyBytes() As Byte =
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System.Text.Encoding.Unicode.GetBytes(key)
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Dim hash() As Byte = sha1.ComputeHash(keyBytes)
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' Truncate or pad the hash.
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ReDim Preserve hash(length - 1)
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Return hash
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End Function
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Public Function EncryptData(
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ByVal plaintext As String) As String
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' Convert the plaintext string to a byte array.
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Dim plaintextBytes() As Byte =
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System.Text.Encoding.Unicode.GetBytes("!Didalog35452Heuchelheim=" & plaintext)
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' Create the stream.
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Dim ms As New System.IO.MemoryStream
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' Create the encoder to write to the stream.
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Dim encStream As New CryptoStream(ms,
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TripleDes.CreateEncryptor(),
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System.Security.Cryptography.CryptoStreamMode.Write)
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' Use the crypto stream to write the byte array to the stream.
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encStream.Write(plaintextBytes, 0, plaintextBytes.Length)
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encStream.FlushFinalBlock()
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' Convert the encrypted stream to a printable string.
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Return Convert.ToBase64String(ms.ToArray)
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End Function
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'Entschlüsselt die Zeichenfolge
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Public Function DecryptData(
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ByVal encryptedtext As String) As String
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Try
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' Convert the encrypted text string to a byte array.
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Dim encryptedBytes() As Byte = Convert.FromBase64String(encryptedtext)
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' Create the stream.
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Dim ms As New System.IO.MemoryStream
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' Create the decoder to write to the stream.
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Dim decStream As New CryptoStream(ms,
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TripleDes.CreateDecryptor(),
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System.Security.Cryptography.CryptoStreamMode.Write)
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' Use the crypto stream to write the byte array to the stream.
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decStream.Write(encryptedBytes, 0, encryptedBytes.Length)
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decStream.FlushFinalBlock()
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Dim result = System.Text.Encoding.Unicode.GetString(ms.ToArray)
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result = result.Replace("!Didalog35452Heuchelheim=", "")
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' Convert the plaintext stream to a string.
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Return result
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Catch ex As Exception
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Logger.Error(ex)
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Return Nothing
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End Try
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End Function
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End Class
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