> I have been playing around with encrypting passwords using a class found in a
> MS KB (see farther down).  It seems to work great so long as the original
> password is comprised of characters on the keyboard.  However, if the
> password is mixed with characters in both ASCII code set 0-127 and 128-255, I
> run into a problem.  Users can set a password using keyboard characters and
> by holding ALT and typing in the decimal value for the non-keyboard
> characters.  The password is encrypted, but when decrypted, it doesn't match
> the original.  I'm not sure if the problem is in the encrypting or decrypting
> or both.
>
> I would GREATLY appreciate it if someone could review the code below and
> discover my problem....
>
> Thanks,
> Mark
> ====================================================
> Imports System.Security.Cryptography
> Public Class Crypto
>
>     ' TAKEN FROM MS KB Q317535
>
>     Public Shared Function EncryptTripleDES(ByVal sIn As String, ByVal sKey
> As String) As String
>         Dim DES As New
> System.Security.Cryptography.TripleDESCryptoServiceProvider()
>         Dim hashMD5 As New
> System.Security.Cryptography.MD5CryptoServiceProvider()
>
>         ' scramble the key
>         sKey = ScrambleKey(sKey)
>         ' Compute the MD5 hash.
>         DES.Key =
> hashMD5.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(sKey))
>         ' Set the cipher mode.
>         DES.Mode = System.Security.Cryptography.CipherMode.ECB
>         ' Create the encryptor.
>         Dim DESEncrypt As System.Security.Cryptography.ICryptoTransform =
> DES.CreateEncryptor()
>         ' Get a byte array of the string.
>         Dim Buffer As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(sIn)
>         ' Transform and return the string.
>         Return Convert.ToBase64String(DESEncrypt.TransformFinalBlock(Buffer,
> 0, Buffer.Length))
>     End Function
>
>     Public Shared Function DecryptTripleDES(ByVal sOut As String, ByVal sKey
> As String) As String
>         Dim DES As New
> System.Security.Cryptography.TripleDESCryptoServiceProvider()
>         Dim hashMD5 As New
> System.Security.Cryptography.MD5CryptoServiceProvider()
>
>
>         ' scramble the key
>         sKey = ScrambleKey(sKey)
>         ' Compute the MD5 hash.
>         DES.Key =
> hashMD5.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(sKey))
>         ' Set the cipher mode.
>         DES.Mode = System.Security.Cryptography.CipherMode.ECB
>         ' Create the decryptor.
>         Dim DESDecrypt As System.Security.Cryptography.ICryptoTransform =
> DES.CreateDecryptor()
>         Dim Buffer As Byte() = Convert.FromBase64String(sOut)
>         ' Transform and return the string.
>         Return
> System.Text.ASCIIEncoding.ASCII.GetString(DESDecrypt.TransformFinalBlock(Buffer, 0, Buffer.Length))
>     End Function
>
>     Private Shared Function ScrambleKey(ByVal v_strKey As String) As String
>
>         Dim sbKey As New System.Text.StringBuilder
>         Dim intPtr As Integer
>         For intPtr = 1 To v_strKey.Length
>             Dim intIn As Integer = v_strKey.Length - intPtr + 1
>             sbKey.Append(Mid(v_strKey, intIn, 1))
>         Next
>
>         Dim strKey As String = sbKey.ToString
>
>         Return sbKey.ToString
>
>     End Function
>
> End Class

"Tom Shelton" wrote:

>
> Mark wrote:
> > I have been playing around with encrypting passwords using a class found in a
> > MS KB (see farther down).  It seems to work great so long as the original
> > password is comprised of characters on the keyboard.  However, if the
> > password is mixed with characters in both ASCII code set 0-127 and 128-255, I
> > run into a problem.  Users can set a password using keyboard characters and
> > by holding ALT and typing in the decimal value for the non-keyboard
> > characters.  The password is encrypted, but when decrypted, it doesn't match
> > the original.  I'm not sure if the problem is in the encrypting or decrypting
> > or both.
> >
> > I would GREATLY appreciate it if someone could review the code below and
> > discover my problem....
> >
> > Thanks,
> > Mark
> > ====================================================
> > Imports System.Security.Cryptography
> > Public Class Crypto
> >
> >     ' TAKEN FROM MS KB Q317535
> >
> >     Public Shared Function EncryptTripleDES(ByVal sIn As String, ByVal sKey
> > As String) As String
> >         Dim DES As New
> > System.Security.Cryptography.TripleDESCryptoServiceProvider()
> >         Dim hashMD5 As New
> > System.Security.Cryptography.MD5CryptoServiceProvider()
> >
> >         ' scramble the key
> >         sKey = ScrambleKey(sKey)
> >         ' Compute the MD5 hash.
> >         DES.Key =
> > hashMD5.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(sKey))
> >         ' Set the cipher mode.
> >         DES.Mode = System.Security.Cryptography.CipherMode.ECB
> >         ' Create the encryptor.
> >         Dim DESEncrypt As System.Security.Cryptography.ICryptoTransform =
> > DES.CreateEncryptor()
> >         ' Get a byte array of the string.
> >         Dim Buffer As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(sIn)
> >         ' Transform and return the string.
> >         Return Convert.ToBase64String(DESEncrypt.TransformFinalBlock(Buffer,
> > 0, Buffer.Length))
> >     End Function
> >
> >     Public Shared Function DecryptTripleDES(ByVal sOut As String, ByVal sKey
> > As String) As String
> >         Dim DES As New
> > System.Security.Cryptography.TripleDESCryptoServiceProvider()
> >         Dim hashMD5 As New
> > System.Security.Cryptography.MD5CryptoServiceProvider()
> >
> >
> >         ' scramble the key
> >         sKey = ScrambleKey(sKey)
> >         ' Compute the MD5 hash.
> >         DES.Key =
> > hashMD5.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(sKey))
> >         ' Set the cipher mode.
> >         DES.Mode = System.Security.Cryptography.CipherMode.ECB
> >         ' Create the decryptor.
> >         Dim DESDecrypt As System.Security.Cryptography.ICryptoTransform =
> > DES.CreateDecryptor()
> >         Dim Buffer As Byte() = Convert.FromBase64String(sOut)
> >         ' Transform and return the string.
> >         Return
> > System.Text.ASCIIEncoding.ASCII.GetString(DESDecrypt.TransformFinalBlock(Buffer, 0, Buffer.Length))
> >     End Function
> >
> >     Private Shared Function ScrambleKey(ByVal v_strKey As String) As String
> >
> >         Dim sbKey As New System.Text.StringBuilder
> >         Dim intPtr As Integer
> >         For intPtr = 1 To v_strKey.Length
> >             Dim intIn As Integer = v_strKey.Length - intPtr + 1
> >             sbKey.Append(Mid(v_strKey, intIn, 1))
> >         Next
> >
> >         Dim strKey As String = sbKey.ToString
> >
> >         Return sbKey.ToString
> >
> >     End Function
> >
> > End Class
>
> Mark...  Well you are using the Encoding.ASCII class.  That is going to
> limit you to the 0-127 range, since that is what ASCII is defined as.
> This is only a guess, but try using the Encoding.Default instead.  That
> should use the default code page - which will probably do what you
> want.
>
> --
> Tom Shelton [MVP]
>
>