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在VB.NET中加密和在PHP中解密

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我试图在 PHP和VB.NET中编写一个函数,它使用 Triple DES来传递加密数据.问题是,当我尝试使用PHP解密在VB.NET中加密的字符串时,我收到一条错误消息,指出IV的块大小必须匹配. 我在VB.NET中编写
我试图在 PHP和VB.NET中编写一个函数,它使用 Triple DES来传递加密数据.问题是,当我尝试使用PHP解密在VB.NET中加密的字符串时,我收到一条错误消息,指出IV的块大小必须匹配.

我在VB.NET中编写的类如下,并且功能齐全,因为它将完美地加密和解密自己的块.

Imports System
    Imports System.Text
    Imports System.IO
    Imports System.Security.Cryptography

    Public Class Cipher

        Dim method As TripleDESCryptoServiceProvider
        Dim key As Byte()

        Public Property Password() As String
            Get
                Return System.Text.Encoding.Unicode.GetString(Key)
            End Get
            Set(value As String)
                key = System.Text.Encoding.Unicode.GetBytes(value)
            End Set
        End Property

        Public Function Encrypt(data As String) As String
            Dim ms As New System.IO.MemoryStream

            ' Create the encoder to write to the stream.
            Dim dataBytes() As Byte = System.Text.Encoding.Unicode.GetBytes(data)
            Dim encStream As New CryptoStream(ms, method.CreateEncryptor(), System.Security.Cryptography.CryptoStreamMode.Write)

            ' Use the crypto stream to write the byte array to the stream.
            encStream.Write(dataBytes, 0, dataBytes.Length)
            encStream.FlushFinalBlock()

            ' IV and Ciphered string are each Base64'd and seperated by a comma, then the whole result is Base64'd
            Return Convert.ToBase64String(System.Text.Encoding.Unicode.GetBytes(Convert.ToBase64String(method.IV) & "," & Convert.ToBase64String(ms.ToArray)))
        End Function

        Public Function Decrypt(data As String) As String
            ' Convert the encrypted text string to a byte array.

            Dim partDecoded As String = System.Text.Encoding.Unicode.GetString(Convert.FromBase64String(data))
            Dim dataBytes() As Byte

            If InStr(partDecoded, ",") > 0 Then

                Dim parts() As String = Split(partDecoded, ",")

                ' Get IV from first part
                method.IV = Convert.FromBase64String(parts(0))

                ' Get ciphered data from second part
                dataBytes = Convert.FromBase64String(parts(1))

                ' Create the stream.
                Dim ms As New System.IO.MemoryStream
                ' Create the decoder to write to the stream.
                Dim decStream As New CryptoStream(ms, method.CreateDecryptor(), System.Security.Cryptography.CryptoStreamMode.Write)

                ' Use the crypto stream to write the byte array to the stream.
                decStream.Write(dataBytes, 0, dataBytes.Length)
                decStream.FlushFinalBlock()

                ' Convert the plaintext stream to a string.
                Return System.Text.Encoding.Unicode.GetString(ms.ToArray)
            Else
                Return False
            End If

        End Function

        Public Sub New()
            method = New TripleDESCryptoServiceProvider
            method.Mode = CipherMode.CFB
            method.GenerateIV()
        End Sub
    End Class

上述类的示例用法

Dim c As New Cipher
    c.Password = "12345"

    Dim encrypted As String = c.Encrypt("hello")
    Debug.Print(encrypted)

    Dim decrypted As String = c.Decrypt(encrypted)
    Debug.Print(decrypted)

现在我还有以下PHP代码(也可以)

class Cipher {
        private $iv;
        private $securekey;

        function __construct($key) {
            $this->securekey = $key;
        }

        function encrypt($string) {
            $this->iv = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_3DES, MCRYPT_MODE_CFB),MCRYPT_DEV_RANDOM);
            $encrypted = base64_encode(mcrypt_encrypt(MCRYPT_3DES, $this->securekey, $string, MCRYPT_MODE_CFB, $this->iv));
            return base64_encode(base64_encode($this->iv) . ',' . $encrypted);
        }

        function decrypt($string) {
            $decrypt = base64_decode($string);
            if(strpos($decrypt,',') > 0) {
                $decrypt = explode(',', $decrypt);
                $this->iv = base64_decode($decrypt[0]);
                return trim(mcrypt_decrypt(MCRYPT_3DES, $this->securekey, base64_decode($decrypt[1]), MCRYPT_MODE_CFB, $this->iv));
            } else {
                return false;
            }
        }
    }

PHP示例用法

$c = new Cipher("12345");
    $encrypted = $c->encrypt("hello");
    echo 'Encrypted: ' . $encrypted . '<br />';

    $decrypted = $c->decrypt($encrypted);
    echo 'Decrypted: ' . $decrypted . '<br />';

    $vb = "MwBOAEoAOQBjAEgAcQAyAC8ASABzAD0ALABmAEUAOQBaAHYAVwBzAFUAYQB3AFYARwBGAHUANABLAGUAVgB3AFcAaABRAD0APQA=";
    echo 'VB.NET Dec: ' . $c->decrypt($vb);

上面我在PHP中使用的内容是用VB.NET编写的Base64字符串,它在VB.NET中将PERFECTLY解码为变量$vb.

这让我非常沮丧,因为代码是正确的,并且功能正常 – 在两种情况下 – 所以我错过了什么,你能指出/解决问题.我不希望使用Rijndael,或者探索其他密码方法,因为这个方法很好,可以在多个设备上本地工作(iOS,Android,Windows,Linux等).

由于没有人能够提供功能齐全的BI-DIRECTIONAL解决方案,我已经冒昧地在本文中为社区提供了一个解决方案.

问题是,PHP不符合标准,强制填充字符串以便匹配.目前,如果在.NET和PHP之间随机生成,没有已知的方法可靠地传递IV(如果你确实发现了如何或者这种变化,请随时修改它).

以下是使用Triple DES加密数据的COMPLETE解决方案,其方式与.NET和PHP兼容,允许双向三重DES加密通信.此方法也与Java,Delphi,Objective-C和许多其他语言兼容,但此类代码不会在此处提供,因为这不是已发布问题的解决方案.

VB.NET Triple DES Class

Imports System
    Imports System.Text
    Imports System.IO
    Imports System.Security.Cryptography

    Public Class TripleDES

        Private bPassword As Byte()
        Private sPassword As String

        Public Sub New(Optional ByVal Password As String = "password")
            ' On Class Begin
            Me.Password = Password
        End Sub

        Public ReadOnly Property PasswordHash As String
            Get
                Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
                Return UTF8.GetString(bPassword)
            End Get
        End Property

        Public Property Password() As String
            Get
                Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
                Return sPassword
            End Get
            Set(value As String)
                Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
                Dim HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                bPassword = HashProvider.ComputeHash(UTF8.GetBytes(value))
                sPassword = value
            End Set
        End Property

    #Region "Encrypt"

        ' Encrypt using Password from Property Set (pre-hashed)
        Public Function Encrypt(ByVal Message As String) As String
            Dim Results() As Byte
            Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
            Using HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                Dim TDESKey() As Byte = bPassword
                Using TDESAlgorithm As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider() With {.Key = TDESKey, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}
                    Dim DataToEncrypt() As Byte = UTF8.GetBytes(Message)
                    Try
                        Dim Encryptor As ICryptoTransform = TDESAlgorithm.CreateEncryptor
                        Results = Encryptor.TransformFinalBlock(DataToEncrypt, 0, DataToEncrypt.Length)
                    Finally
                        TDESAlgorithm.Clear()
                        HashProvider.Clear()
                    End Try
                End Using
            End Using
            Return Convert.ToBase64String(Results)
        End Function

        ' Encrypt using Password as byte array
        Private Function Encrypt(ByVal Message As String, ByVal Password() As Byte) As String
            Dim Results() As Byte
            Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
            Using HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                Dim TDESKey() As Byte = HashProvider.ComputeHash(UTF8.GetBytes(UTF8.GetString(Password)))
                Using TDESAlgorithm As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider() With {.Key = TDESKey, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}
                    Dim DataToEncrypt() As Byte = UTF8.GetBytes(Message)
                    Try
                        Dim Encryptor As ICryptoTransform = TDESAlgorithm.CreateEncryptor
                        Results = Encryptor.TransformFinalBlock(DataToEncrypt, 0, DataToEncrypt.Length)
                    Finally
                        TDESAlgorithm.Clear()
                        HashProvider.Clear()
                    End Try
                End Using
            End Using
            Return Convert.ToBase64String(Results)
        End Function

        ' Encrypt using Password as string
        Public Function Encrypt(ByVal Message As String, ByVal Password As String) As String
            Dim Results() As Byte
            Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
            ' Step 1. We hash the Passphrase using MD5
            ' We use the MD5 hash generator as the result is a 128 bit byte array
            ' which is a valid length for the Triple DES encoder we use below
            Using HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                Dim TDESKey() As Byte = HashProvider.ComputeHash(UTF8.GetBytes(Password))

                ' Step 2. Create a new TripleDESCryptoServiceProvider object

                ' Step 3. Setup the encoder
                Using TDESAlgorithm As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider() With {.Key = TDESKey, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}
                    ' Step 4. Convert the input string to a byte[]

                    Dim DataToEncrypt() As Byte = UTF8.GetBytes(Message)

                    ' Step 5. Attempt to encrypt the string
                    Try
                        Dim Encryptor As ICryptoTransform = TDESAlgorithm.CreateEncryptor
                        Results = Encryptor.TransformFinalBlock(DataToEncrypt, 0, DataToEncrypt.Length)
                    Finally
                        ' Clear the Triple Des and Hashprovider services of any sensitive information
                        TDESAlgorithm.Clear()
                        HashProvider.Clear()
                    End Try
                End Using
            End Using

            ' Step 6. Return the encrypted string as a base64 encoded string
            Return Convert.ToBase64String(Results)
        End Function
    #End Region

    #Region "Decrypt"
        ' Decrypt using Password from Property (pre-hashed)
        Public Function Decrypt(ByVal Message As String) As String
            Dim Results() As Byte
            Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
            Using HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                Dim TDESKey() As Byte = Me.bPassword
                Using TDESAlgorithm As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider() With {.Key = TDESKey, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}
                    Dim DataToDecrypt() As Byte = Convert.FromBase64String(Message)
                    Try
                        Dim Decryptor As ICryptoTransform = TDESAlgorithm.CreateDecryptor
                        Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length)
                    Finally
                        TDESAlgorithm.Clear()
                        HashProvider.Clear()
                    End Try
                End Using
            End Using
            Return UTF8.GetString(Results)
        End Function

        ' Decrypt using Password as Byte array
        Public Function Decrypt(ByVal Message As String, ByVal Password() As Byte) As String
            Dim Results() As Byte
            Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
            Using HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                Dim TDESKey() As Byte = HashProvider.ComputeHash(UTF8.GetBytes(UTF8.GetString(Password)))
                Using TDESAlgorithm As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider() With {.Key = TDESKey, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}
                    Dim DataToDecrypt() As Byte = Convert.FromBase64String(Message)
                    Try
                        Dim Decryptor As ICryptoTransform = TDESAlgorithm.CreateDecryptor
                        Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length)
                    Finally
                        TDESAlgorithm.Clear()
                        HashProvider.Clear()
                    End Try
                End Using
            End Using
            Return UTF8.GetString(Results)
        End Function


        ' Decrypt using Password as string
        Public Function Decrypt(ByVal Message As String, ByVal Password As String) As String
            Dim Results() As Byte
            Dim UTF8 As System.Text.UTF8Encoding = New System.Text.UTF8Encoding

            ' Step 1. We hash the pass phrase using MD5
            ' We use the MD5 hash generator as the result is a 128-bit byte array
            ' which is a valid length for the Triple DES encoder we use below
            Using HashProvider As MD5CryptoServiceProvider = New MD5CryptoServiceProvider()
                Dim TDESKey() As Byte = HashProvider.ComputeHash(UTF8.GetBytes(Password))

                ' Step 2. Create a new TripleDESCryptoServiceProvider object
                ' Step 3. Setup the decoder
                Using TDESAlgorithm As TripleDESCryptoServiceProvider = New TripleDESCryptoServiceProvider() With {.Key = TDESKey, .Mode = CipherMode.ECB, .Padding = PaddingMode.PKCS7}

                    ' Step 4. Convert the input string to a byte[]
                    Dim DataToDecrypt() As Byte = Convert.FromBase64String(Message)
                    ' Step 5. Attempt to decrypt the string
                    Try
                        Dim Decryptor As ICryptoTransform = TDESAlgorithm.CreateDecryptor
                        Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length)
                    Finally

                        ' Clear the Triple Des and Hash provider services of any sensitive information
                        TDESAlgorithm.Clear()
                        HashProvider.Clear()
                    End Try
                End Using
            End Using

            ' Step 6. Return the decrypted string in UTF8 format
            Return UTF8.GetString(Results)
        End Function

    #End Region

    End Class

VB.NET Triple DES类用法

Dim tdes As New TripleDES("12345")
    Dim vbEncrypted = tdes.Encrypt("Encrypted using VB.NET")
    Dim phpEncrypted = "5Ittyr0+jiI7QQmPrvSVnMc9MEWQCjAN"

    Debug.Print("PHP Encrypted: " & phpEncrypted)
    Debug.Print("VB Encrypted: " & vbEncrypted)
    Debug.Print("PHP Encrypted (decrypted result): " & tdes.Decrypt(phpEncrypted))
    Debug.Print("VB Encrypted (decrypted result): " & tdes.Decrypt(vbEncrypted))

PHP三重DES类

class TripleDES {
        private $bPassword;
        private $sPassword;

        function __construct($Password) {
            $this->bPassword  = md5(utf8_encode($Password),TRUE);
            $this->bPassword .= substr($this->bPassword,0,8);
            $this->sPassword - $Password;
        }

        function Password($Password = "") {
            if($Password == "") {
                return $this->sPassword;
            } else {
                $this->bPassword  = md5(utf8_encode($Password),TRUE);
                $this->bPassword .= substr($this->bPassword,0,8);
                $this->sPassword - $Password;
            }
        }

        function PasswordHash() {
            return $this->bPassword;
        }

        function Encrypt($Message, $Password = "") {
            if($Password <> "") { $this->Password($Password); }
            $size=mcrypt_get_block_size('tripledes','ecb');
            $padding=$size-((strlen($Message)) % $size);
            $Message .= str_repeat(chr($padding),$padding);
            $encrypt  = mcrypt_encrypt('tripledes',$this->bPassword,$Message,'ecb');
            return base64_encode($encrypt);
        }

        function Decrypt($message, $Password = "") {
            if($Password <> "") { $this->Password($Password); }
            return trim(mcrypt_decrypt('tripledes', $this->bPassword, base64_decode($message), 'ecb'), ord(2));
        }

    }

PHP Triple DES类用法

$tdes = new TripleDES("12345");

    $phpEncrypted = $tdes->encrypt("Encrypted using PHP");
    $vbEncrypted = "5Ittyr0+jiI7QQmPrvSVnP3s2CeoTJmF"; // Encrypted using VB.NET

    echo "PHP Encrypted: " . $phpEncrypted . '<br />';
    echo "VB Encrypted: " . $vbEncrypted . '<br />';
    echo "PHP Encrypted (decrypted result): " . $tdes->Decrypt($phpEncrypted) . '<br />';
    echo "VB Encrypted (decrypted result): " . $tdes->Decrypt($vbEncrypted) . '<br />';

我尽我所能使两个类的可用性水平相同,因为语言自然允许.由于PHP不允许重载函数,我不得不使用密码作为可选参数,这是一个字符串值. VB.NET解决方案有一个额外的覆盖,允许您在加密/解密函数上传递密码字符串的字节值.提供示例代码以显示每个的用法,显示了实例化对象的最简单形式,两个类都允许在对象创建时设置密码.

对于其他任何人都在抨击他们的大脑试图找到一个三重DES的工作双向解决方案(并且不想被强制进入每个人似乎指向的方框 – Rijndael),那么这个解决方案是为你,你可以不停地撞到墙上.

添加了VB.NET TripleDES类的C#转换

C#类(已添加[2017-01-11])

using System;
using System.Security.Cryptography;

public class TripleDES {

    private byte[] bPassword;

    private string sPassword;
    public TripleDES( string Password = "password" ) {
        // On Class Begin
        this.Password = Password;
    }

    public string PasswordHash {
        get {
            System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
            return UTF8.GetString( bPassword );
        }
    }

    public string Password {
        get {
            System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
            return sPassword;
        }
        set {
            System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
            MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider();
            bPassword = HashProvider.ComputeHash( UTF8.GetBytes( value ) );
            sPassword = value;
        }
    }

    #region "Encrypt"

    // Encrypt using Password from Property Set (pre-hashed)
    public string Encrypt( string Message ) {
        byte[] Results = null;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
        using ( MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider() ) {
            byte[] TDESKey = bPassword;
            using ( TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider { Key = TDESKey, Mode = CipherMode.ECB, Padding = PaddingMode.PKCS7 } ) {
                byte[] DataToEncrypt = UTF8.GetBytes( Message );
                try {
                    ICryptoTransform Encryptor = TDESAlgorithm.CreateEncryptor();
                    Results = Encryptor.TransformFinalBlock( DataToEncrypt, 0, DataToEncrypt.Length );
                } finally {
                    TDESAlgorithm.Clear();
                    HashProvider.Clear();
                }
            }
        }
        return Convert.ToBase64String( Results );
    }

    // Encrypt using Password as byte array
    private string Encrypt( string Message, byte[] Password ) {
        byte[] Results = null;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
        using ( MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider() ) {
            byte[] TDESKey = HashProvider.ComputeHash( UTF8.GetBytes( UTF8.GetString( Password ) ) );
            using ( TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider { Key = TDESKey, Mode = CipherMode.ECB, Padding = PaddingMode.PKCS7 } ) {
                byte[] DataToEncrypt = UTF8.GetBytes( Message );
                try {
                    ICryptoTransform Encryptor = TDESAlgorithm.CreateEncryptor();
                    Results = Encryptor.TransformFinalBlock( DataToEncrypt, 0, DataToEncrypt.Length );
                } finally {
                    TDESAlgorithm.Clear();
                    HashProvider.Clear();
                }
            }
        }
        return Convert.ToBase64String( Results );
    }

    // Encrypt using Password as string
    public string Encrypt( string Message, string Password ) {
        byte[] Results = null;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
        // Step 1. We hash the Passphrase using MD5
        // We use the MD5 hash generator as the result is a 128 bit byte array
        // which is a valid length for the Triple DES encoder we use below
        using ( MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider() ) {
            byte[] TDESKey = HashProvider.ComputeHash( UTF8.GetBytes( Password ) );

            // Step 2. Create a new TripleDESCryptoServiceProvider object

            // Step 3. Setup the encoder
            using ( TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider { Key = TDESKey, Mode = CipherMode.ECB, Padding = PaddingMode.PKCS7 } ) {
                // Step 4. Convert the input string to a byte[]

                byte[] DataToEncrypt = UTF8.GetBytes( Message );

                // Step 5. Attempt to encrypt the string
                try {
                    ICryptoTransform Encryptor = TDESAlgorithm.CreateEncryptor();
                    Results = Encryptor.TransformFinalBlock( DataToEncrypt, 0, DataToEncrypt.Length );
                } finally {
                    // Clear the Triple Des and Hashprovider services of any sensitive information
                    TDESAlgorithm.Clear();
                    HashProvider.Clear();
                }
            }
        }

        // Step 6. Return the encrypted string as a base64 encoded string
        return Convert.ToBase64String( Results );
    }
    #endregion

    #region "Decrypt"
    // Decrypt using Password from Property (pre-hashed)
    public string Decrypt( string Message ) {
        byte[] Results = null;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
        using ( MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider() ) {
            byte[] TDESKey = this.bPassword;
            using ( TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider { Key = TDESKey, Mode = CipherMode.ECB, Padding = PaddingMode.PKCS7 } ) {
                byte[] DataToDecrypt = Convert.FromBase64String( Message );
                try {
                    ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
                    Results = Decryptor.TransformFinalBlock( DataToDecrypt, 0, DataToDecrypt.Length );
                } finally {
                    TDESAlgorithm.Clear();
                    HashProvider.Clear();
                }
            }
        }
        return UTF8.GetString( Results );
    }

    // Decrypt using Password as Byte array
    public string Decrypt( string Message, byte[] Password ) {
        byte[] Results = null;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
        using ( MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider() ) {
            byte[] TDESKey = HashProvider.ComputeHash( UTF8.GetBytes( UTF8.GetString( Password ) ) );
            using ( TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider { Key = TDESKey, Mode = CipherMode.ECB, Padding = PaddingMode.PKCS7 } ) {
                byte[] DataToDecrypt = Convert.FromBase64String( Message );
                try {
                    ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
                    Results = Decryptor.TransformFinalBlock( DataToDecrypt, 0, DataToDecrypt.Length );
                } finally {
                    TDESAlgorithm.Clear();
                    HashProvider.Clear();
                }
            }
        }
        return UTF8.GetString( Results );
    }


    // Decrypt using Password as string
    public string Decrypt( string Message, string Password ) {
        byte[] Results = null;
        System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();

        // Step 1. We hash the pass phrase using MD5
        // We use the MD5 hash generator as the result is a 128-bit byte array
        // which is a valid length for the Triple DES encoder we use below
        using ( MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider() ) {
            byte[] TDESKey = HashProvider.ComputeHash( UTF8.GetBytes( Password ) );

            // Step 2. Create a new TripleDESCryptoServiceProvider object
            // Step 3. Setup the decoder
            using ( TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider { Key = TDESKey, Mode = CipherMode.ECB, Padding = PaddingMode.PKCS7 } ) {

                // Step 4. Convert the input string to a byte[]
                byte[] DataToDecrypt = Convert.FromBase64String( Message );
                // Step 5. Attempt to decrypt the string
                try {
                    ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
                    Results = Decryptor.TransformFinalBlock( DataToDecrypt, 0, DataToDecrypt.Length );

                } finally {
                    // Clear the Triple Des and Hash provider services of any sensitive information
                    TDESAlgorithm.Clear();
                    HashProvider.Clear();
                }
            }
        }

        // Step 6. Return the decrypted string in UTF8 format
        return UTF8.GetString( Results );
    }

    #endregion
}
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