ProtectedConfigurationProvider Class (System.Configuration)

Imports System
Imports System.Xml
Imports System.Security.Cryptography
Imports System.IO
Imports System.Text
Imports System.Configuration.Provider
Imports System.Collections.Specialized
Imports System.Configuration


' Shows how to create a custom protected configuration
' provider.
Namespace Samples.AspNet

    Public Class TripleDESProtectedConfigurationProvider
        Inherits ProtectedConfigurationProvider

        Private des _
        As New TripleDESCryptoServiceProvider()

        Private pKeyFilePath As String
        Private pName As String

        ' Gets the path of the file
        ' containing the key used to
        ' encrypt/decrypt.

        Public ReadOnly Property KeyFilePath() As String
            Get
                Return pKeyFilePath
            End Get
        End Property

        ' Gets the provider name.

        Public Overrides ReadOnly Property Name() As String
            Get
                Return pName
            End Get
        End Property


        ' Performs provider initialization.
        Public Overrides Sub Initialize( _
        ByVal name As String, _
        ByVal config As NameValueCollection)
            pName = name
            pKeyFilePath = config("keyContainerName")
            ReadKey(KeyFilePath)
        End Sub 'Initialize


        ' Performs encryption.
        Public Overrides Function Encrypt( _
        ByVal node As XmlNode) As XmlNode
            Dim encryptedData As String = _
            EncryptString(node.OuterXml)

            Dim xmlDoc As New XmlDocument()
            xmlDoc.PreserveWhitespace = True
            xmlDoc.LoadXml( _
            ("<EncryptedData>" + encryptedData + _
            "</EncryptedData>"))

            Return xmlDoc.DocumentElement
        End Function 'Encrypt

        ' Performs decryption.
        Public Overrides Function Decrypt( _
        ByVal encryptedNode As XmlNode) As XmlNode
            Dim decryptedData As String = _
            DecryptString(encryptedNode.InnerText)

            Dim xmlDoc As New XmlDocument()
            xmlDoc.PreserveWhitespace = True
            xmlDoc.LoadXml(decryptedData)

            Return xmlDoc.DocumentElement
        End Function 'Decrypt



        ' Encrypts a configuration section and returns 
        ' the encrypted XML as a string.
        Private Function EncryptString( _
        ByVal encryptValue As String) As String
            Dim valBytes As Byte() = _
            Encoding.Unicode.GetBytes(encryptValue)

            Dim transform As ICryptoTransform = _
            des.CreateEncryptor()

            Dim ms As New MemoryStream()
            Dim cs As New CryptoStream(ms, _
            transform, CryptoStreamMode.Write)
            cs.Write(valBytes, 0, valBytes.Length)
            cs.FlushFinalBlock()
            Dim returnBytes As Byte() = ms.ToArray()
            cs.Close()

            Return Convert.ToBase64String(returnBytes)
        End Function 'EncryptString



        ' Decrypts an encrypted configuration section and 
        ' returns the unencrypted XML as a string.
        Private Function DecryptString( _
        ByVal encryptedValue As String) As String
            Dim valBytes As Byte() = _
            Convert.FromBase64String(encryptedValue)

            Dim transform As ICryptoTransform = _
            des.CreateDecryptor()

            Dim ms As New MemoryStream()
            Dim cs As New CryptoStream(ms, _
            transform, CryptoStreamMode.Write)
            cs.Write(valBytes, 0, valBytes.Length)
            cs.FlushFinalBlock()
            Dim returnBytes As Byte() = ms.ToArray()
            cs.Close()

            Return Encoding.Unicode.GetString(returnBytes)
        End Function 'DecryptString


        ' Generates a new TripleDES key and vector and 
        ' writes them to the supplied file path.
        Public Sub CreateKey(ByVal filePath As String)
            des.GenerateKey()
            des.GenerateIV()

            Dim sw As New StreamWriter(filePath, False)
            sw.WriteLine(ByteToHex(des.Key))
            sw.WriteLine(ByteToHex(des.IV))
            sw.Close()
        End Sub 'CreateKey



        ' Reads in the TripleDES key and vector from 
        ' the supplied file path and sets the Key 
        ' and IV properties of the 
        ' TripleDESCryptoServiceProvider.
        Private Sub ReadKey(ByVal filePath As String)
            Dim sr As New StreamReader(filePath)
            Dim keyValue As String = sr.ReadLine()
            Dim ivValue As String = sr.ReadLine()
            des.Key = HexToByte(keyValue)
            des.IV = HexToByte(ivValue)
        End Sub 'ReadKey



        ' Converts a byte array to a hexadecimal string.
        Private Function ByteToHex( _
        ByVal byteArray() As Byte) As String
            Dim outString As String = ""

            Dim b As [Byte]
            For Each b In byteArray
                outString += b.ToString("X2")
            Next b
            Return outString
        End Function 'ByteToHex


        ' Converts a hexadecimal string to a byte array.
        Private Function HexToByte(ByVal hexString As String) As Byte()
            Dim returnBytes(hexString.Length / 2) As Byte
            Dim i As Integer
            For i = 0 To returnBytes.Length - 1
                returnBytes(i) = _
                Convert.ToByte(hexString.Substring(i * 2, 2), 16)
            Next i
            Return returnBytes
        End Function 'HexToByte
    End Class 'TripleDESProtectedConfigurationProvider 

End Namespace

using System;
using System.Xml;
using System.Security.Cryptography;
using System.IO;
using System.Text;
using System.Configuration.Provider;
using System.Collections.Specialized;
using System.Configuration;

namespace Samples.AspNet
{
    // Shows how to create a custom protected configuration
    // provider.
    public class TripleDESProtectedConfigurationProvider :
        ProtectedConfigurationProvider
    {

        private TripleDESCryptoServiceProvider des =
            new TripleDESCryptoServiceProvider();

        private string pKeyFilePath;
        private string pName;

        // Gets the path of the file
        // containing the key used to
        // encryption or decryption.
        public string KeyFilePath
        {
            get { return pKeyFilePath; }
        }


        // Gets the provider name.
        public override string Name
        {
            get { return pName; }
        }


        // Performs provider initialization.
        public override void Initialize(string name,
            NameValueCollection config)
        {
            pName = name;
            pKeyFilePath = config["keyContainerName"];
            ReadKey(KeyFilePath);
        }


        // Performs encryption.
        public override XmlNode Encrypt(XmlNode node)
        {
            string encryptedData = EncryptString(node.OuterXml);

            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.PreserveWhitespace = true;
            xmlDoc.LoadXml("<EncryptedData>" +
                encryptedData + "</EncryptedData>");

            return xmlDoc.DocumentElement;
        }

        // Performs decryption.
        public override XmlNode Decrypt(XmlNode encryptedNode)
        {
            string decryptedData =
                DecryptString(encryptedNode.InnerText);

            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.PreserveWhitespace = true;
            xmlDoc.LoadXml(decryptedData);

            return xmlDoc.DocumentElement;
        }

        // Encrypts a configuration section and returns 
        // the encrypted XML as a string.
        private string EncryptString(string encryptValue)
        {
            byte[] valBytes =
                Encoding.Unicode.GetBytes(encryptValue);

            ICryptoTransform transform = des.CreateEncryptor();

            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms,
                transform, CryptoStreamMode.Write);
            cs.Write(valBytes, 0, valBytes.Length);
            cs.FlushFinalBlock();
            byte[] returnBytes = ms.ToArray();
            cs.Close();

            return Convert.ToBase64String(returnBytes);
        }


        // Decrypts an encrypted configuration section and 
        // returns the unencrypted XML as a string.
        private string DecryptString(string encryptedValue)
        {
            byte[] valBytes =
                Convert.FromBase64String(encryptedValue);

            ICryptoTransform transform = des.CreateDecryptor();

            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms,
                transform, CryptoStreamMode.Write);
            cs.Write(valBytes, 0, valBytes.Length);
            cs.FlushFinalBlock();
            byte[] returnBytes = ms.ToArray();
            cs.Close();

            return Encoding.Unicode.GetString(returnBytes);
        }

        // Generates a new TripleDES key and vector and 
        // writes them to the supplied file path.
        public void CreateKey(string filePath)
        {
            des.GenerateKey();
            des.GenerateIV();

            StreamWriter sw = new StreamWriter(filePath, false);
            sw.WriteLine(ByteToHex(des.Key));
            sw.WriteLine(ByteToHex(des.IV));
            sw.Close();
        }


        // Reads in the TripleDES key and vector from 
        // the supplied file path and sets the Key 
        // and IV properties of the 
        // TripleDESCryptoServiceProvider.
        private void ReadKey(string filePath)
        {
            StreamReader sr = new StreamReader(filePath);
            string keyValue = sr.ReadLine();
            string ivValue = sr.ReadLine();
            des.Key = HexToByte(keyValue);
            des.IV = HexToByte(ivValue);
        }


        // Converts a byte array to a hexadecimal string.
        private string ByteToHex(byte[] byteArray)
        {
            string outString = "";

            foreach (Byte b in byteArray)
                outString += b.ToString("X2");

            return outString;
        }

        // Converts a hexadecimal string to a byte array.
        private byte[] HexToByte(string hexString)
        {
            byte[] returnBytes = new byte[hexString.Length / 2];
            for (int i = 0; i < returnBytes.Length; i++)
                returnBytes[i] =
                    Convert.ToByte(hexString.Substring(i * 2, 2), 16);
            return returnBytes;
        }

    }

}

Imports System
Imports System.Configuration

Namespace Samples.AspNet
    ' Show how to use a custom protected configuration
    ' provider.

    Public Class TestingProtectedConfigurationProvider


        ' Protect the connectionStrings section.
        Private Shared Sub ProtectConfiguration()

            ' Get the application configuration file.
            Dim config _
            As System.Configuration.Configuration = _
            ConfigurationManager.OpenExeConfiguration( _
            ConfigurationUserLevel.None)

            ' Define the provider name.
            Dim provider As String = _
            "TripleDESProtectedConfigurationProvider"

            ' Get the section to protect.
            Dim connStrings _
            As ConfigurationSection = config.ConnectionStrings

            If Not (connStrings Is Nothing) Then
                If Not connStrings.SectionInformation.IsProtected Then
                    If Not connStrings.ElementInformation.IsLocked Then
                        ' Protect the section.
                        connStrings.SectionInformation.ProtectSection( _
                        provider)

                        connStrings.SectionInformation.ForceSave = True
                        config.Save(ConfigurationSaveMode.Full)

                        Console.WriteLine( _
                        "Section {0} is now protected by {1}", _
                        connStrings.SectionInformation.Name, _
                        connStrings.SectionInformation.ProtectionProvider.Name)

                    Else
                        Console.WriteLine( _
                        "Can't protect, section {0} is locked", _
                        connStrings.SectionInformation.Name)
                    End If
                Else
                    Console.WriteLine( _
                    "Section {0} is already protected by {1}", _
                    connStrings.SectionInformation.Name, _
                    connStrings.SectionInformation.ProtectionProvider.Name)
                End If

            Else
                Console.WriteLine( _
                "Can't get the section {0}", _
                connStrings.SectionInformation.Name)
            End If
        End Sub 'ProtectConfiguration


        ' Unprotect the connectionStrings section.
        Private Shared Sub UnProtectConfiguration()

            ' Get the application configuration file.
            Dim config _
            As System.Configuration.Configuration = _
            ConfigurationManager.OpenExeConfiguration( _
            ConfigurationUserLevel.None)

            ' Get the section to unprotect.
            Dim connStrings _
            As ConfigurationSection = config.ConnectionStrings

            If Not (connStrings Is Nothing) Then
                If connStrings.SectionInformation.IsProtected Then
                    If Not connStrings.ElementInformation.IsLocked Then
                        ' Unprotect the section.
                        connStrings.SectionInformation.UnprotectSection()

                        connStrings.SectionInformation.ForceSave = True
                        config.Save(ConfigurationSaveMode.Full)

                        Console.WriteLine( _
                        "Section {0} is now unprotected.", _
                        connStrings.SectionInformation.Name)

                    Else
                        Console.WriteLine( _
                        "Can't unprotect, section {0} is locked", _
                        connStrings.SectionInformation.Name)
                    End If
                Else
                    Console.WriteLine( _
                    "Section {0} is already unprotected.", _
                    connStrings.SectionInformation.Name)
                End If

            Else
                Console.WriteLine( _
                "Can't get the section {0}", _
                connStrings.SectionInformation.Name)
            End If
        End Sub 'UnProtectConfiguration



        Public Shared Sub Main(ByVal args() As String)

            Dim selection As String = String.Empty

            If args.Length = 0 Then
                Console.WriteLine( _
                "Select createkey, protect or unprotect")
                Return
            End If

            selection = args(0).ToLower()

            Select Case selection

                ' Create the key to use during 
                ' encryption/decryption.
                Case "createkey"
                    Dim keyContainer As String = "pcKey.txt"

                    ' Instantiate the custom provider.
                    Dim provider _
                    As New TripleDESProtectedConfigurationProvider()

                    ' Create the encryption/decryption key.
                    provider.CreateKey(keyContainer)

                    Console.WriteLine( _
                    "New TripleDES key created in {0}", _
                    keyContainer)

                Case "protect"
                    ProtectConfiguration()

                Case "unprotect"
                    UnProtectConfiguration()

                Case Else
                    Console.WriteLine("Unknown selection")
            End Select

            Console.Read()
        End Sub 'Main 
    End Class 'TestingProtectedConfigurationProvider
End Namespace

using System;
using System.Configuration;
using Samples.AspNet.Configuration;

namespace Samples.AspNet.Configuration
{

    // Show how to use a custom protected configuration
    // provider.
    public class TestingProtectedConfigurationProvider
    {

        // Protect the connectionStrings section.
        private static void ProtectConfiguration()
        {

            // Get the application configuration file.
            System.Configuration.Configuration config =
                    ConfigurationManager.OpenExeConfiguration(
                    ConfigurationUserLevel.None);

            // Define the provider name.
            string provider =
                "TripleDESProtectedConfigurationProvider";

            // Get the section to protect.
            ConfigurationSection connStrings =
                config.ConnectionStrings;

            if (connStrings != null)
            {
                if (!connStrings.SectionInformation.IsProtected)
                {
                    if (!connStrings.ElementInformation.IsLocked)
                    {
                        // Protect the section.
                        connStrings.SectionInformation.ProtectSection(provider);

                        connStrings.SectionInformation.ForceSave = true;
                        config.Save(ConfigurationSaveMode.Full);

                        Console.WriteLine("Section {0} is now protected by {1}",
                            connStrings.SectionInformation.Name,
                            connStrings.SectionInformation.ProtectionProvider.Name);

                    }
                    else
                        Console.WriteLine(
                             "Can't protect, section {0} is locked",
                             connStrings.SectionInformation.Name);
                }
                else
                    Console.WriteLine(
                        "Section {0} is already protected by {1}",
                        connStrings.SectionInformation.Name,
                        connStrings.SectionInformation.ProtectionProvider.Name);

            }
            else
                Console.WriteLine("Can't get the section {0}",
                    connStrings.SectionInformation.Name);

        }

        // Unprotect the connectionStrings section.
        private static void UnProtectConfiguration()
        {

            // Get the application configuration file.
            System.Configuration.Configuration config =
                    ConfigurationManager.OpenExeConfiguration(
                    ConfigurationUserLevel.None);

            // Get the section to unprotect.
            ConfigurationSection connStrings =
                config.ConnectionStrings;

            if (connStrings != null)
            {
                if (connStrings.SectionInformation.IsProtected)
                {
                    if (!connStrings.ElementInformation.IsLocked)
                    {
                        // Unprotect the section.
                        connStrings.SectionInformation.UnprotectSection();

                        connStrings.SectionInformation.ForceSave = true;
                        config.Save(ConfigurationSaveMode.Full);

                        Console.WriteLine("Section {0} is now unprotected.",
                            connStrings.SectionInformation.Name);

                    }
                    else
                        Console.WriteLine(
                             "Can't unprotect, section {0} is locked",
                             connStrings.SectionInformation.Name);
                }
                else
                    Console.WriteLine(
                        "Section {0} is already unprotected.",
                        connStrings.SectionInformation.Name);

            }
            else
                Console.WriteLine("Can't get the section {0}",
                    connStrings.SectionInformation.Name);

        }


        public static void Main(string[] args)
        {

            string selection = string.Empty;

            if (args.Length == 0)
            {
                Console.WriteLine(
                    "Select createkey, protect or unprotect");
                return;
            }

            selection = args[0].ToLower();

            switch (selection)
            {

                // Create the key to use during 
                // encryption/decryption.
                case "createkey":
                    string keyContainer = 
                        "pcKey.txt";

                    // Instantiate the custom provider.
                    TripleDESProtectedConfigurationProvider 
                        provider =
                        new TripleDESProtectedConfigurationProvider();

                    // Create the encryption/decryption key.
                    provider.CreateKey(keyContainer);

                    Console.WriteLine(
                        "New TripleDES key created in {0}",
                        keyContainer);
                    break;

                case "protect":
                    ProtectConfiguration();
                    break;

                case "unprotect":
                    UnProtectConfiguration();
                    break;

                default:
                    Console.WriteLine("Unknown selection");
                    break;
            }

            Console.Read();

        }


    }

}