[VB.NET] Encryption

**1BAD33** · 28-06-2009 01:17 PM

Need a simple function to encrypt a string and decrypt it while being able to write it to a regular text file. I tried a method and it did not work because it produced some invalid text file characters... Anyone got any ideas to encrypt some stuff? Anyone got some code?

***Ivo*** · 28-06-2009 10:09 PM

How secure is the encryption supposed to be? What are you encrypting?

If its a password look up using sha1 for .NET, hashing is what you want instead of encryption.

You can Base64 encode it to obfuscate it if you want...

**chemicalNova** · 29-06-2009 08:22 AM

BAM!

Code:

Imports System.IO
Imports System.Security.Cryptography
Imports System.Text
Imports System.Text.RegularExpressions
Imports System.Configuration

Namespace Encryption

#Region "Hash"

    Public Class Hash
        Public Enum Provider
            CRC32
            SHA1
            SHA256
            SHA384
            SHA512
            MD5
        End Enum

        Private _Hash As HashAlgorithm
        Private _HashValue As New Data

        Private Sub New()
        End Sub

        Public Sub New(ByVal p As Provider)
            Select Case p
                Case Provider.CRC32
                    _Hash = New CRC32
                Case Provider.MD5
                    _Hash = New MD5CryptoServiceProvider
                Case Provider.SHA1
                    _Hash = New SHA1Managed
                Case Provider.SHA256
                    _Hash = New SHA256Managed
                Case Provider.SHA384
                    _Hash = New SHA384Managed
                Case Provider.SHA512
                    _Hash = New SHA512Managed
            End Select
        End Sub

        Public ReadOnly Property Value() As Data
            Get
                Return _HashValue
            End Get
        End Property

        Public Function Calculate(ByRef s As System.IO.Stream) As Data
            _HashValue.Bytes = _Hash.ComputeHash(s)
            Return _HashValue
        End Function

        Public Function Calculate(ByVal d As Data) As Data
            Return CalculatePrivate(d.Bytes)
        End Function

        Public Function Calculate(ByVal d As Data, ByVal salt As Data) As Data
            Dim nb(d.Bytes.Length + salt.Bytes.Length - 1) As Byte
            salt.Bytes.CopyTo(nb, 0)
            d.Bytes.CopyTo(nb, salt.Bytes.Length)
            Return CalculatePrivate(nb)
        End Function

        Private Function CalculatePrivate(ByVal b() As Byte) As Data
            _HashValue.Bytes = _Hash.ComputeHash(b)
            Return _HashValue
        End Function

#Region "CRC32 HashAlgorithm"
        Private Class CRC32
            Inherits HashAlgorithm

            Private result As Integer = &HFFFFFFFF

            Protected Overrides Sub HashCore(ByVal array() As Byte, ByVal ibStart As Integer, ByVal cbSize As Integer)
                Dim lookup As Integer
                For i As Integer = ibStart To cbSize - 1
                    lookup = (result And &HFF) Xor array(i)
                    result = ((result And &HFFFFFF00) \ &H100) And &HFFFFFF
                    result = result Xor crcLookup(lookup)
                Next i
            End Sub

            Protected Overrides Function HashFinal() As Byte()
                Dim b() As Byte = BitConverter.GetBytes(Not result)
                Array.Reverse(b)
                Return b
            End Function

            Public Overrides Sub Initialize()
                result = &HFFFFFFFF
            End Sub

            Private crcLookup() As Integer = { _
                &H0, &H77073096, &HEE0E612C, &H990951BA, _
                &H76DC419, &H706AF48F, &HE963A535, &H9E6495A3, _
                &HEDB8832, &H79DCB8A4, &HE0D5E91E, &H97D2D988, _
                &H9B64C2B, &H7EB17CBD, &HE7B82D07, &H90BF1D91, _
                &H1DB71064, &H6AB020F2, &HF3B97148, &H84BE41DE, _
                &H1ADAD47D, &H6DDDE4EB, &HF4D4B551, &H83D385C7, _
                &H136C9856, &H646BA8C0, &HFD62F97A, &H8A65C9EC, _
                &H14015C4F, &H63066CD9, &HFA0F3D63, &H8D080DF5, _
                &H3B6E20C8, &H4C69105E, &HD56041E4, &HA2677172, _
                &H3C03E4D1, &H4B04D447, &HD20D85FD, &HA50AB56B, _
                &H35B5A8FA, &H42B2986C, &HDBBBC9D6, &HACBCF940, _
                &H32D86CE3, &H45DF5C75, &HDCD60DCF, &HABD13D59, _
                &H26D930AC, &H51DE003A, &HC8D75180, &HBFD06116, _
                &H21B4F4B5, &H56B3C423, &HCFBA9599, &HB8BDA50F, _
                &H2802B89E, &H5F058808, &HC60CD9B2, &HB10BE924, _
                &H2F6F7C87, &H58684C11, &HC1611DAB, &HB6662D3D, _
                &H76DC4190, &H1DB7106, &H98D220BC, &HEFD5102A, _
                &H71B18589, &H6B6B51F, &H9FBFE4A5, &HE8B8D433, _
                &H7807C9A2, &HF00F934, &H9609A88E, &HE10E9818, _
                &H7F6A0DBB, &H86D3D2D, &H91646C97, &HE6635C01, _
                &H6B6B51F4, &H1C6C6162, &H856530D8, &HF262004E, _
                &H6C0695ED, &H1B01A57B, &H8208F4C1, &HF50FC457, _
                &H65B0D9C6, &H12B7E950, &H8BBEB8EA, &HFCB9887C, _
                &H62DD1DDF, &H15DA2D49, &H8CD37CF3, &HFBD44C65, _
                &H4DB26158, &H3AB551CE, &HA3BC0074, &HD4BB30E2, _
                &H4ADFA541, &H3DD895D7, &HA4D1C46D, &HD3D6F4FB, _
                &H4369E96A, &H346ED9FC, &HAD678846, &HDA60B8D0, _
                &H44042D73, &H33031DE5, &HAA0A4C5F, &HDD0D7CC9, _
                &H5005713C, &H270241AA, &HBE0B1010, &HC90C2086, _
                &H5768B525, &H206F85B3, &HB966D409, &HCE61E49F, _
                &H5EDEF90E, &H29D9C998, &HB0D09822, &HC7D7A8B4, _
                &H59B33D17, &H2EB40D81, &HB7BD5C3B, &HC0BA6CAD, _
                &HEDB88320, &H9ABFB3B6, &H3B6E20C, &H74B1D29A, _
                &HEAD54739, &H9DD277AF, &H4DB2615, &H73DC1683, _
                &HE3630B12, &H94643B84, &HD6D6A3E, &H7A6A5AA8, _
                &HE40ECF0B, &H9309FF9D, &HA00AE27, &H7D079EB1, _
                &HF00F9344, &H8708A3D2, &H1E01F268, &H6906C2FE, _
                &HF762575D, &H806567CB, &H196C3671, &H6E6B06E7, _
                &HFED41B76, &H89D32BE0, &H10DA7A5A, &H67DD4ACC, _
                &HF9B9DF6F, &H8EBEEFF9, &H17B7BE43, &H60B08ED5, _
                &HD6D6A3E8, &HA1D1937E, &H38D8C2C4, &H4FDFF252, _
                &HD1BB67F1, &HA6BC5767, &H3FB506DD, &H48B2364B, _
                &HD80D2BDA, &HAF0A1B4C, &H36034AF6, &H41047A60, _
                &HDF60EFC3, &HA867DF55, &H316E8EEF, &H4669BE79, _
                &HCB61B38C, &HBC66831A, &H256FD2A0, &H5268E236, _
                &HCC0C7795, &HBB0B4703, &H220216B9, &H5505262F, _
                &HC5BA3BBE, &HB2BD0B28, &H2BB45A92, &H5CB36A04, _
                &HC2D7FFA7, &HB5D0CF31, &H2CD99E8B, &H5BDEAE1D, _
                &H9B64C2B0, &HEC63F226, &H756AA39C, &H26D930A, _
                &H9C0906A9, &HEB0E363F, &H72076785, &H5005713, _
                &H95BF4A82, &HE2B87A14, &H7BB12BAE, &HCB61B38, _
                &H92D28E9B, &HE5D5BE0D, &H7CDCEFB7, &HBDBDF21, _
                &H86D3D2D4, &HF1D4E242, &H68DDB3F8, &H1FDA836E, _
                &H81BE16CD, &HF6B9265B, &H6FB077E1, &H18B74777, _
                &H88085AE6, &HFF0F6A70, &H66063BCA, &H11010B5C, _
                &H8F659EFF, &HF862AE69, &H616BFFD3, &H166CCF45, _
                &HA00AE278, &HD70DD2EE, &H4E048354, &H3903B3C2, _
                &HA7672661, &HD06016F7, &H4969474D, &H3E6E77DB, _
                &HAED16A4A, &HD9D65ADC, &H40DF0B66, &H37D83BF0, _
                &HA9BCAE53, &HDEBB9EC5, &H47B2CF7F, &H30B5FFE9, _
                &HBDBDF21C, &HCABAC28A, &H53B39330, &H24B4A3A6, _
                &HBAD03605, &HCDD70693, &H54DE5729, &H23D967BF, _
                &HB3667A2E, &HC4614AB8, &H5D681B02, &H2A6F2B94, _
                &HB40BBE37, &HC30C8EA1, &H5A05DF1B, &H2D02EF8D}

            Public Overrides ReadOnly Property Hash() As Byte()
                Get
                    Dim b() As Byte = BitConverter.GetBytes(Not result)
                    Array.Reverse(b)
                    Return b
                End Get
            End Property
        End Class

#End Region

    End Class
#End Region

#Region "Symmetric"

    Public Class Symmetric

        Private Const _DefaultIntializationVector As String = "%1Az=-@qT"
        Private Const _BufferSize As Integer = 2048

        Public Enum Provider
            DES
            RC2
            Rijndael
            TripleDES
        End Enum

        Private _data As Data
        Private _key As Data
        Private _iv As Data
        Private _crypto As SymmetricAlgorithm
        Private _EncryptedBytes As Byte()
        Private _UseDefaultInitializationVector As Boolean

        Private Sub New()
        End Sub

        Public Sub New(ByVal provider As Provider, Optional ByVal useDefaultInitializationVector As Boolean = True)
            Select Case provider
                Case provider.DES
                    _crypto = New DESCryptoServiceProvider
                Case provider.RC2
                    _crypto = New RC2CryptoServiceProvider
                Case provider.Rijndael
                    _crypto = New RijndaelManaged
                Case provider.TripleDES
                    _crypto = New TripleDESCryptoServiceProvider
            End Select

            '-- make sure key and IV are always set, no matter what
            Me.Key = RandomKey()
            If useDefaultInitializationVector Then
                Me.IntializationVector = New Data(_DefaultIntializationVector)
            Else
                Me.IntializationVector = RandomInitializationVector()
            End If
        End Sub

        Public Property KeySizeBytes() As Integer
            Get
                Return _crypto.KeySize \ 8
            End Get
            Set(ByVal Value As Integer)
                _crypto.KeySize = Value * 8
                _key.MaxBytes = Value
            End Set
        End Property

        Public Property KeySizeBits() As Integer
            Get
                Return _crypto.KeySize
            End Get
            Set(ByVal Value As Integer)
                _crypto.KeySize = Value
                _key.MaxBits = Value
            End Set
        End Property

        Public Property Key() As Data
            Get
                Return _key
            End Get
            Set(ByVal Value As Data)
                _key = Value
                _key.MaxBytes = _crypto.LegalKeySizes(0).MaxSize \ 8
                _key.MinBytes = _crypto.LegalKeySizes(0).MinSize \ 8
                _key.StepBytes = _crypto.LegalKeySizes(0).SkipSize \ 8
            End Set
        End Property

        Public Property IntializationVector() As Data
            Get
                Return _iv
            End Get
            Set(ByVal Value As Data)
                _iv = Value
                _iv.MaxBytes = _crypto.BlockSize \ 8
                _iv.MinBytes = _crypto.BlockSize \ 8
            End Set
        End Property

        Public Function RandomInitializationVector() As Data
            _crypto.GenerateIV()
            Dim d As New Data(_crypto.IV)
            Return d
        End Function

        Public Function RandomKey() As Data
            _crypto.GenerateKey()
            Dim d As New Data(_crypto.Key)
            Return d
        End Function

        Private Sub ValidateKeyAndIv(ByVal isEncrypting As Boolean)
            If _key.IsEmpty Then
                If isEncrypting Then
                    _key = RandomKey()
                Else
                    Throw New CryptographicException("No key was provided for the decryption operation!")
                End If
            End If
            If _iv.IsEmpty Then
                If isEncrypting Then
                    _iv = RandomInitializationVector()
                Else
                    Throw New CryptographicException("No initialization vector was provided for the decryption operation!")
                End If
            End If
            _crypto.Key = _key.Bytes
            _crypto.IV = _iv.Bytes
        End Sub

        Public Function Encrypt(ByVal d As Data, ByVal key As Data) As Data
            Me.Key = key
            Return Encrypt(d)
        End Function

        Public Function Encrypt(ByVal d As Data) As Data
            Dim ms As New IO.MemoryStream

            ValidateKeyAndIv(True)

            Dim cs As New CryptoStream(ms, _crypto.CreateEncryptor(), CryptoStreamMode.Write)
            cs.Write(d.Bytes, 0, d.Bytes.Length)
            cs.Close()
            ms.Close()

            Return New Data(ms.ToArray)
        End Function

        Public Function Encrypt(ByVal s As Stream, ByVal key As Data, ByVal iv As Data) As Data
            Me.IntializationVector = iv
            Me.Key = key
            Return Encrypt(s)
        End Function

        Public Function Encrypt(ByVal s As Stream, ByVal key As Data) As Data
            Me.Key = key
            Return Encrypt(s)
        End Function

        Public Function Encrypt(ByVal s As Stream) As Data
            Dim ms As New IO.MemoryStream
            Dim b(_BufferSize) As Byte
            Dim i As Integer

            ValidateKeyAndIv(True)

            Dim cs As New CryptoStream(ms, _crypto.CreateEncryptor(), CryptoStreamMode.Write)
            i = s.Read(b, 0, _BufferSize)
            Do While i > 0
                cs.Write(b, 0, i)
                i = s.Read(b, 0, _BufferSize)
            Loop

            cs.Close()
            ms.Close()

            Return New Data(ms.ToArray)
        End Function

        Public Function Decrypt(ByVal encryptedData As Data, ByVal key As Data) As Data
            Me.Key = key
            Return Decrypt(encryptedData)
        End Function

        Public Function Decrypt(ByVal encryptedStream As Stream, ByVal key As Data) As Data
            Me.Key = key
            Return Decrypt(encryptedStream)
        End Function

        Public Function Decrypt(ByVal encryptedStream As Stream) As Data
            Dim ms As New System.IO.MemoryStream
            Dim b(_BufferSize) As Byte

            ValidateKeyAndIv(False)
            Dim cs As New CryptoStream(encryptedStream, _
                _crypto.CreateDecryptor(), CryptoStreamMode.Read)

            Dim i As Integer
            i = cs.Read(b, 0, _BufferSize)

            Do While i > 0
                ms.Write(b, 0, i)
                i = cs.Read(b, 0, _BufferSize)
            Loop
            cs.Close()
            ms.Close()

            Return New Data(ms.ToArray)
        End Function

        Public Function Decrypt(ByVal encryptedData As Data) As Data
            Dim ms As New System.IO.MemoryStream(encryptedData.Bytes, 0, encryptedData.Bytes.Length)
            Dim b() As Byte = New Byte(encryptedData.Bytes.Length - 1) {}

            ValidateKeyAndIv(False)
            Dim cs As New CryptoStream(ms, _crypto.CreateDecryptor(), CryptoStreamMode.Read)

            Try
                cs.Read(b, 0, encryptedData.Bytes.Length - 1)
            Catch ex As CryptographicException
                Throw New CryptographicException("Unable to decrypt data. The provided key may be invalid.", ex)
            Finally
                cs.Close()
            End Try
            Return New Data(b)
        End Function

    End Class

#End Region

#Region "Asymmetric"

    Public Class Asymmetric

        Private _rsa As RSACryptoServiceProvider
        Private _KeyContainerName As String = "Encryption.AsymmetricEncryption.DefaultContainerName"
        Private _UseMachineKeystore As Boolean = True
        Private _KeySize As Integer = 1024

        Private Const _ElementParent As String = "RSAKeyValue"
        Private Const _ElementModulus As String = "Modulus"
        Private Const _ElementExponent As String = "Exponent"
        Private Const _ElementPrimeP As String = "P"
        Private Const _ElementPrimeQ As String = "Q"
        Private Const _ElementPrimeExponentP As String = "DP"
        Private Const _ElementPrimeExponentQ As String = "DQ"
        Private Const _ElementCoefficient As String = "InverseQ"
        Private Const _ElementPrivateExponent As String = "D"

        '-- http://forum.java.sun.com/thread.jsp?forum=9&thread=552022&tstart=0&trange=15 
        Private Const _KeyModulus As String = "PublicKey.Modulus"
        Private Const _KeyExponent As String = "PublicKey.Exponent"
        Private Const _KeyPrimeP As String = "PrivateKey.P"
        Private Const _KeyPrimeQ As String = "PrivateKey.Q"
        Private Const _KeyPrimeExponentP As String = "PrivateKey.DP"
        Private Const _KeyPrimeExponentQ As String = "PrivateKey.DQ"
        Private Const _KeyCoefficient As String = "PrivateKey.InverseQ"
        Private Const _KeyPrivateExponent As String = "PrivateKey.D"

#Region "PublicKey Class"

        Public Class PublicKey
            Public Modulus As String
            Public Exponent As String

            Public Sub New()
            End Sub

            Public Sub New(ByVal KeyXml As String)
                LoadFromXml(KeyXml)
            End Sub

            Public Sub LoadFromConfig()
                Me.Modulus = Utils.GetConfigString(_KeyModulus)
                Me.Exponent = Utils.GetConfigString(_KeyExponent)
            End Sub

            Public Function ToConfigSection() As String
                Dim sb As New StringBuilder
                With sb
                    .Append(Utils.WriteConfigKey(_KeyModulus, Me.Modulus))
                    .Append(Utils.WriteConfigKey(_KeyExponent, Me.Exponent))
                End With
                Return sb.ToString
            End Function

            Public Sub ExportToConfigFile(ByVal filePath As String)
                Dim sw As New StreamWriter(filePath, False)
                sw.Write(Me.ToConfigSection)
                sw.Close()
            End Sub

            Public Sub LoadFromXml(ByVal keyXml As String)
                Me.Modulus = Utils.GetXmlElement(keyXml, "Modulus")
                Me.Exponent = Utils.GetXmlElement(keyXml, "Exponent")
            End Sub

            Public Function ToParameters() As RSAParameters
                Dim r As New RSAParameters
                r.Modulus = Convert.FromBase64String(Me.Modulus)
                r.Exponent = Convert.FromBase64String(Me.Exponent)
                Return r
            End Function

            Public Function ToXml() As String
                Dim sb As New StringBuilder
                With sb
                    .Append(Utils.WriteXmlNode(_ElementParent))
                    .Append(Utils.WriteXmlElement(_ElementModulus, Me.Modulus))
                    .Append(Utils.WriteXmlElement(_ElementExponent, Me.Exponent))
                    .Append(Utils.WriteXmlNode(_ElementParent, True))
                End With
                Return sb.ToString
            End Function

            Public Sub ExportToXmlFile(ByVal filePath As String)
                Dim sw As New StreamWriter(filePath, False)
                sw.Write(Me.ToXml)
                sw.Close()
            End Sub

        End Class
#End Region

#Region "PrivateKey Class"

        Public Class PrivateKey
            Public Modulus As String
            Public Exponent As String
            Public PrimeP As String
            Public PrimeQ As String
            Public PrimeExponentP As String
            Public PrimeExponentQ As String
            Public Coefficient As String
            Public PrivateExponent As String

            Public Sub New()
            End Sub

            Public Sub New(ByVal keyXml As String)
                LoadFromXml(keyXml)
            End Sub

            Public Sub LoadFromConfig()
                Me.Modulus = Utils.GetConfigString(_KeyModulus)
                Me.Exponent = Utils.GetConfigString(_KeyExponent)
                Me.PrimeP = Utils.GetConfigString(_KeyPrimeP)
                Me.PrimeQ = Utils.GetConfigString(_KeyPrimeQ)
                Me.PrimeExponentP = Utils.GetConfigString(_KeyPrimeExponentP)
                Me.PrimeExponentQ = Utils.GetConfigString(_KeyPrimeExponentQ)
                Me.Coefficient = Utils.GetConfigString(_KeyCoefficient)
                Me.PrivateExponent = Utils.GetConfigString(_KeyPrivateExponent)
            End Sub

            Public Function ToParameters() As RSAParameters
                Dim r As New RSAParameters
                r.Modulus = Convert.FromBase64String(Me.Modulus)
                r.Exponent = Convert.FromBase64String(Me.Exponent)
                r.P = Convert.FromBase64String(Me.PrimeP)
                r.Q = Convert.FromBase64String(Me.PrimeQ)
                r.DP = Convert.FromBase64String(Me.PrimeExponentP)
                r.DQ = Convert.FromBase64String(Me.PrimeExponentQ)
                r.InverseQ = Convert.FromBase64String(Me.Coefficient)
                r.D = Convert.FromBase64String(Me.PrivateExponent)
                Return r
            End Function

            Public Function ToConfigSection() As String
                Dim sb As New StringBuilder
                With sb
                    .Append(Utils.WriteConfigKey(_KeyModulus, Me.Modulus))
                    .Append(Utils.WriteConfigKey(_KeyExponent, Me.Exponent))
                    .Append(Utils.WriteConfigKey(_KeyPrimeP, Me.PrimeP))
                    .Append(Utils.WriteConfigKey(_KeyPrimeQ, Me.PrimeQ))
                    .Append(Utils.WriteConfigKey(_KeyPrimeExponentP, Me.PrimeExponentP))
                    .Append(Utils.WriteConfigKey(_KeyPrimeExponentQ, Me.PrimeExponentQ))
                    .Append(Utils.WriteConfigKey(_KeyCoefficient, Me.Coefficient))
                    .Append(Utils.WriteConfigKey(_KeyPrivateExponent, Me.PrivateExponent))
                End With
                Return sb.ToString
            End Function

            Public Sub ExportToConfigFile(ByVal strFilePath As String)
                Dim sw As New StreamWriter(strFilePath, False)
                sw.Write(Me.ToConfigSection)
                sw.Close()
            End Sub

            Public Sub LoadFromXml(ByVal keyXml As String)
                Me.Modulus = Utils.GetXmlElement(keyXml, "Modulus")
                Me.Exponent = Utils.GetXmlElement(keyXml, "Exponent")
                Me.PrimeP = Utils.GetXmlElement(keyXml, "P")
                Me.PrimeQ = Utils.GetXmlElement(keyXml, "Q")
                Me.PrimeExponentP = Utils.GetXmlElement(keyXml, "DP")
                Me.PrimeExponentQ = Utils.GetXmlElement(keyXml, "DQ")
                Me.Coefficient = Utils.GetXmlElement(keyXml, "InverseQ")
                Me.PrivateExponent = Utils.GetXmlElement(keyXml, "D")
            End Sub

            Public Function ToXml() As String
                Dim sb As New StringBuilder
                With sb
                    .Append(Utils.WriteXmlNode(_ElementParent))
                    .Append(Utils.WriteXmlElement(_ElementModulus, Me.Modulus))
                    .Append(Utils.WriteXmlElement(_ElementExponent, Me.Exponent))
                    .Append(Utils.WriteXmlElement(_ElementPrimeP, Me.PrimeP))
                    .Append(Utils.WriteXmlElement(_ElementPrimeQ, Me.PrimeQ))
                    .Append(Utils.WriteXmlElement(_ElementPrimeExponentP, Me.PrimeExponentP))
                    .Append(Utils.WriteXmlElement(_ElementPrimeExponentQ, Me.PrimeExponentQ))
                    .Append(Utils.WriteXmlElement(_ElementCoefficient, Me.Coefficient))
                    .Append(Utils.WriteXmlElement(_ElementPrivateExponent, Me.PrivateExponent))
                    .Append(Utils.WriteXmlNode(_ElementParent, True))
                End With
                Return sb.ToString
            End Function

            Public Sub ExportToXmlFile(ByVal filePath As String)
                Dim sw As New StreamWriter(filePath, False)
                sw.Write(Me.ToXml)
                sw.Close()
            End Sub

        End Class

#End Region

        Public Sub New()
            _rsa = GetRSAProvider()
        End Sub

        Public Sub New(ByVal keySize As Integer)
            _KeySize = keySize
            _rsa = GetRSAProvider()
        End Sub

        Public Property KeyContainerName() As String
            Get
                Return _KeyContainerName
            End Get
            Set(ByVal Value As String)
                _KeyContainerName = Value
            End Set
        End Property

        Public ReadOnly Property KeySizeBits() As Integer
            Get
                Return _rsa.KeySize
            End Get
        End Property

        Public ReadOnly Property KeySizeMaxBits() As Integer
            Get
                Return _rsa.LegalKeySizes(0).MaxSize
            End Get
        End Property

        Public ReadOnly Property KeySizeMinBits() As Integer
            Get
                Return _rsa.LegalKeySizes(0).MinSize
            End Get
        End Property

        Public ReadOnly Property KeySizeStepBits() As Integer
            Get
                Return _rsa.LegalKeySizes(0).SkipSize
            End Get
        End Property

        Public ReadOnly Property DefaultPublicKey() As PublicKey
            Get
                Dim pubkey As New PublicKey
                pubkey.LoadFromConfig()
                Return pubkey
            End Get
        End Property

        Public ReadOnly Property DefaultPrivateKey() As PrivateKey
            Get
                Dim privkey As New PrivateKey
                privkey.LoadFromConfig()
                Return privkey
            End Get
        End Property

        Public Sub GenerateNewKeyset(ByRef publicKey As PublicKey, ByRef privateKey As PrivateKey)
            Dim PublicKeyXML As String = Nothing
            Dim PrivateKeyXML As String = Nothing
            GenerateNewKeyset(PublicKeyXML, PrivateKeyXML)
            publicKey = New PublicKey(PublicKeyXML)
            privateKey = New PrivateKey(PrivateKeyXML)
        End Sub

        Public Sub GenerateNewKeyset(ByRef publicKeyXML As String, ByRef privateKeyXML As String)
            Dim rsa As RSA = RSACryptoServiceProvider.Create
            publicKeyXML = rsa.ToXmlString(False)
            privateKeyXML = rsa.ToXmlString(True)
        End Sub

        Public Function Encrypt(ByVal d As Data) As Data
            Dim PublicKey As PublicKey = DefaultPublicKey
            Return Encrypt(d, PublicKey)
        End Function

        Public Function Encrypt(ByVal d As Data, ByVal publicKey As PublicKey) As Data
            _rsa.ImportParameters(publicKey.ToParameters)
            Return EncryptPrivate(d)
        End Function

        Public Function Encrypt(ByVal d As Data, ByVal publicKeyXML As String) As Data
            LoadKeyXml(publicKeyXML, False)
            Return EncryptPrivate(d)
        End Function

        Private Function EncryptPrivate(ByVal d As Data) As Data
            Try
                Return New Data(_rsa.Encrypt(d.Bytes, False))
            Catch ex As CryptographicException
                If ex.Message.ToLower.IndexOf("bad length") > -1 Then
                    Throw New CryptographicException("Your data is too large; RSA encryption is designed to encrypt relatively small amounts of data. The exact byte limit depends on the key size. To encrypt more data, use symmetric encryption and then encrypt that symmetric key with asymmetric RSA encryption.", ex)
                Else
                    Throw
                End If
            End Try
        End Function

        Public Function Decrypt(ByVal encryptedData As Data) As Data
            Dim PrivateKey As New PrivateKey
            PrivateKey.LoadFromConfig()
            Return Decrypt(encryptedData, PrivateKey)
        End Function

        Public Function Decrypt(ByVal encryptedData As Data, ByVal PrivateKey As PrivateKey) As Data
            _rsa.ImportParameters(PrivateKey.ToParameters)
            Return DecryptPrivate(encryptedData)
        End Function

        Public Function Decrypt(ByVal encryptedData As Data, ByVal PrivateKeyXML As String) As Data
            LoadKeyXml(PrivateKeyXML, True)
            Return DecryptPrivate(encryptedData)
        End Function

        Private Sub LoadKeyXml(ByVal keyXml As String, ByVal isPrivate As Boolean)
            Try
                _rsa.FromXmlString(keyXml)
            Catch ex As System.Security.XmlSyntaxException
                Dim s As String
                If isPrivate Then
                    s = "private"
                Else
                    s = "public"
                End If
                Throw New System.Security.XmlSyntaxException( _
                    String.Format("The provided {0} encryption key XML does not appear to be valid.", s), ex)
            End Try
        End Sub

        Private Function DecryptPrivate(ByVal encryptedData As Data) As Data
            Return New Data(_rsa.Decrypt(encryptedData.Bytes, False))
        End Function

        Private Function GetRSAProvider() As RSACryptoServiceProvider
            Dim rsa As RSACryptoServiceProvider = Nothing
            Dim csp As CspParameters = Nothing
            Try
                csp = New CspParameters
                csp.KeyContainerName = _KeyContainerName
                rsa = New RSACryptoServiceProvider(_KeySize, csp)
                rsa.PersistKeyInCsp = False
                RSACryptoServiceProvider.UseMachineKeyStore = True
                Return rsa
            Catch ex As System.Security.Cryptography.CryptographicException
                If ex.Message.ToLower.IndexOf("csp for this implementation could not be acquired") > -1 Then
                    Throw New Exception("Unable to obtain Cryptographic Service Provider. " & _
                        "Either the permissions are incorrect on the " & _
                        "'C:\Documents and Settings\All Users\Application Data\Microsoft\Crypto\RSA\MachineKeys' " & _
                        "folder, or the current security context '" & System.Security.Principal.WindowsIdentity.GetCurrent.Name & "'" & _
                        " does not have access to this folder.", ex)
                Else
                    Throw
                End If
            Finally
                If Not rsa Is Nothing Then
                    rsa = Nothing
                End If
                If Not csp Is Nothing Then
                    csp = Nothing
                End If
            End Try
        End Function

    End Class

#End Region

#Region "Data"

    Public Class Data
        Private _b As Byte()
        Private _MaxBytes As Integer = 0
        Private _MinBytes As Integer = 0
        Private _StepBytes As Integer = 0

        Public Shared DefaultEncoding As Text.Encoding = System.Text.Encoding.GetEncoding("Windows-1252")

        Public Encoding As Text.Encoding = DefaultEncoding

        Public Sub New()
        End Sub

        Public Sub New(ByVal b As Byte())
            _b = b
        End Sub

        Public Sub New(ByVal s As String)
            Me.Text = s
        End Sub

        Public Sub New(ByVal s As String, ByVal encoding As System.Text.Encoding)
            Me.Encoding = encoding
            Me.Text = s
        End Sub

        Public ReadOnly Property IsEmpty() As Boolean
            Get
                If _b Is Nothing Then
                    Return True
                End If
                If _b.Length = 0 Then
                    Return True
                End If
                Return False
            End Get
        End Property

        Public Property StepBytes() As Integer
            Get
                Return _StepBytes
            End Get
            Set(ByVal Value As Integer)
                _StepBytes = Value
            End Set
        End Property

        Public Property StepBits() As Integer
            Get
                Return _StepBytes * 8
            End Get
            Set(ByVal Value As Integer)
                _StepBytes = Value \ 8
            End Set
        End Property

        Public Property MinBytes() As Integer
            Get
                Return _MinBytes
            End Get
            Set(ByVal Value As Integer)
                _MinBytes = Value
            End Set
        End Property

        Public Property MinBits() As Integer
            Get
                Return _MinBytes * 8
            End Get
            Set(ByVal Value As Integer)
                _MinBytes = Value \ 8
            End Set
        End Property

        Public Property MaxBytes() As Integer
            Get
                Return _MaxBytes
            End Get
            Set(ByVal Value As Integer)
                _MaxBytes = Value
            End Set
        End Property

        Public Property MaxBits() As Integer
            Get
                Return _MaxBytes * 8
            End Get
            Set(ByVal Value As Integer)
                _MaxBytes = Value \ 8
            End Set
        End Property

        Public Property Bytes() As Byte()
            Get
                If _MaxBytes > 0 Then
                    If _b.Length > _MaxBytes Then
                        Dim b(_MaxBytes - 1) As Byte
                        Array.Copy(_b, b, b.Length)
                        _b = b
                    End If
                End If
                If _MinBytes > 0 Then
                    If _b.Length < _MinBytes Then
                        Dim b(_MinBytes - 1) As Byte
                        Array.Copy(_b, b, _b.Length)
                        _b = b
                    End If
                End If
                Return _b
            End Get
            Set(ByVal Value As Byte())
                _b = Value
            End Set
        End Property

        Public Property Text() As String
            Get
                If _b Is Nothing Then
                    Return ""
                Else
                    '-- need to handle nulls here; oddly, C# will happily convert
                    '-- nulls into the string whereas VB stops converting at the
                    '-- first null!
                    Dim i As Integer = Array.IndexOf(_b, CType(0, Byte))
                    If i >= 0 Then
                        Return Me.Encoding.GetString(_b, 0, i)
                    Else
                        Return Me.Encoding.GetString(_b)
                    End If
                End If
            End Get
            Set(ByVal Value As String)
                _b = Me.Encoding.GetBytes(Value)
            End Set
        End Property

        Public Property Hex() As String
            Get
                Return Utils.ToHex(_b)
            End Get
            Set(ByVal Value As String)
                _b = Utils.FromHex(Value)
            End Set
        End Property

        Public Property Base64() As String
            Get
                Return Utils.ToBase64(_b)
            End Get
            Set(ByVal Value As String)
                _b = Utils.FromBase64(Value)
            End Set
        End Property

        Public Shadows Function ToString() As String
            Return Me.Text
        End Function

        Public Function ToBase64() As String
            Return Me.Base64
        End Function

        Public Function ToHex() As String
            Return Me.Hex
        End Function

    End Class

#End Region

#Region "Utils"

    Friend Class Utils

        Friend Shared Function ToHex(ByVal ba() As Byte) As String
            If ba Is Nothing OrElse ba.Length = 0 Then
                Return ""
            End If
            Const HexFormat As String = "{0:X2}"
            Dim sb As New StringBuilder
            For Each b As Byte In ba
                sb.Append(String.Format(HexFormat, b))
            Next
            Return sb.ToString
        End Function

        Friend Shared Function FromHex(ByVal hexEncoded As String) As Byte()
            If hexEncoded Is Nothing OrElse hexEncoded.Length = 0 Then
                Return Nothing
            End If
            Try
                Dim l As Integer = Convert.ToInt32(hexEncoded.Length / 2)
                Dim b(l - 1) As Byte
                For i As Integer = 0 To l - 1
                    b(i) = Convert.ToByte(hexEncoded.Substring(i * 2, 2), 16)
                Next
                Return b
            Catch ex As Exception
                Throw New System.FormatException("The provided string does not appear to be Hex encoded:" & _
                    Environment.NewLine & hexEncoded & Environment.NewLine, ex)
            End Try
        End Function

        Friend Shared Function FromBase64(ByVal base64Encoded As String) As Byte()
            If base64Encoded Is Nothing OrElse base64Encoded.Length = 0 Then
                Return Nothing
            End If
            Try
                Return Convert.FromBase64String(base64Encoded)
            Catch ex As System.FormatException
                Throw New System.FormatException("The provided string does not appear to be Base64 encoded:" & _
                    Environment.NewLine & base64Encoded & Environment.NewLine, ex)
            End Try
        End Function

        Friend Shared Function ToBase64(ByVal b() As Byte) As String
            If b Is Nothing OrElse b.Length = 0 Then
                Return ""
            End If
            Return Convert.ToBase64String(b)
        End Function

        Friend Shared Function GetXmlElement(ByVal xml As String, ByVal element As String) As String
            Dim m As Match
            m = Regex.Match(xml, "<" & element & ">(?<Element>[^>]*)</" & element & ">", RegexOptions.IgnoreCase)
            If m Is Nothing Then
                Throw New Exception("Could not find <" & element & "></" & element & "> in provided Public Key XML.")
            End If
            Return m.Groups("Element").ToString
        End Function

        Friend Shared Function GetConfigString(ByVal key As String, _
            Optional ByVal isRequired As Boolean = True) As String

            Dim s As String = CType(ConfigurationManager.AppSettings.Get(key), String)
            If s = Nothing Then
                If isRequired Then
                    Throw New ConfigurationErrorsException("key <" & key & "> is missing from .config file")
                Else
                    Return ""
                End If
            Else
                Return s
            End If
        End Function

        Friend Shared Function WriteConfigKey(ByVal key As String, ByVal value As String) As String
            Dim s As String = "<add key=""{0}"" value=""{1}"" />" & Environment.NewLine
            Return String.Format(s, key, value)
        End Function

        Friend Shared Function WriteXmlElement(ByVal element As String, ByVal value As String) As String
            Dim s As String = "<{0}>{1}</{0}>" & Environment.NewLine
            Return String.Format(s, element, value)
        End Function

        Friend Shared Function WriteXmlNode(ByVal element As String, Optional ByVal isClosing As Boolean = False) As String
            Dim s As String
            If isClosing Then
                s = "</{0}>" & Environment.NewLine
            Else
                s = "<{0}>" & Environment.NewLine
            End If
            Return String.Format(s, element)
        End Function

    End Class

#End Region

End Namespace

Example usage (of TripleDES encryption):

Code:

Dim key As String = "poiQWE098!@#"
Dim p As Encryption.Symmetric.Provider = Encryption.Symmetric.Provider.TripleDES
Dim sym As New Encryption.Symmetric(p)
sym.Key.Text = key

Dim encryptedData As Encryption.Data

encryptedData = sym.Encrypt(New Encryption.Data("I AM ENCRYPTING THIS DATA"))

Example decryption:

Code:

Dim DecryptData As Encryption.Data
Dim p As Encryption.Symmetric.Provider = Encryption.Symmetric.Provider.TripleDES
Dim key As New Encryption.Data("poiQWE098!@#")

Dim enc As New Encryption.Symmetric(p)

DecryptData = new Encryption.Data(<encrypted data here>)
MessageBox.Show(enc.Decrypt(DecryptData, key).ToString())

EDIT: Added examples..

chem

**1BAD33** · 29-06-2009 05:47 PM

I got scared, chem.

Ill try make use of that, thanks. If fails, ill just base64 some strings. Its for personal use anyway, I just don't trust english holding sensitive words.

On a similar note, anyone know why this is throwing a "{"Value cannot be null. Parameter name: item"}" Says something about using "new" or something. Any ideas? Red line is where the problem lies.

Code:

Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("db.ini")
            MyReader.TextFieldType = FileIO.FieldType.Delimited
            MyReader.SetDelimiters(",")
            Dim currentRow As String()
            Dim i As Integer = 0
            Dim x As Integer = 0
            Dim y As Integer = 0
            While Not MyReader.EndOfData
                Try
                    currentRow = MyReader.ReadFields()
                    Dim currentField As String
                    For Each currentField In currentRow
                        i = i + 1
                        If i Mod 2 = 0 Then
                            '  MsgBox("Password is: " + currentField)
                            passwordArray(y) = currentField
                            y = y + 1
                        Else
                            ' MsgBox("Username is: " + currentField)
                            usernameArray(x) = currentField
                            x = x + 1
                        End If
                    Next
                Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
                    MsgBox("Line " & ex.Message & _
                    "is not valid and will be skipped.")
                End Try
            End While
            MyReader.Close()

        End Using

        For Each tempStr In usernameArray

            cboAccounts.Items.Add(tempStr)
        Next

**chemicalNova** · 30-06-2009 07:19 AM

Your usernameArray is either empty, or the values stored in it are null.

The only parameter in the comboBox.Items.Add() method is "item". You're passing a null value (tempStr) to it.

chem

**1BAD33** · 30-06-2009 11:55 AM

Hmm you're right. tempStr is blank second time around. WTF? I'm re-running the same code. Why would it work the first time and not again...

Hmm but you can see what the code is trying to do. I'm reading a text file with structure

username,password

and placing username into a username array and the combo box and password into an array and differentiating between the two by checking if they are odd or even numbered. Is there a different way to do this(left side of comma in cbo box and array and right side into a new array)

**chemicalNova** · 30-06-2009 12:09 PM

Well, currentRow will return the values on that line in a string array.. so I would do this:

Code:

' <chemicalNova>
        Dim usernameList As New List(Of String)
        Dim passwordList As New List(Of String)
        ' </chemicalNova>

        Using MyReader As New Microsoft.VisualBasic.FileIO.TextFieldParser("db.ini")
            MyReader.TextFieldType = FileIO.FieldType.Delimited
            MyReader.SetDelimiters(",")
            Dim currentRow As String()
            Dim i As Integer = 0
            Dim x As Integer = 0
            Dim y As Integer = 0
            While Not MyReader.EndOfData
                Try
                    ' <chemicalNova>
                    currentRow = MyReader.ReadFields()
                    usernameList.Add(currentRow(0))
                    passwordList.Add(currentRow(1))
                    ' </chemicalNova>
                Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
                    MsgBox("Line " & ex.Message & _
                    "is not valid and will be skipped.")
                End Try
            End While
            MyReader.Close()
        End Using

        For Each tempStr In usernameList
            cboAccounts.Items.Add(tempStr)
        Next

chem

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