ProtectedConfigurationProvider Classe

Definição

public ref class ProtectedConfigurationProvider abstract : System::Configuration::Provider::ProviderBase

public abstract class ProtectedConfigurationProvider : System.Configuration.Provider.ProviderBase

type ProtectedConfigurationProvider = class
    inherit ProviderBase

Public MustInherit Class ProtectedConfigurationProvider
Inherits ProviderBase

Herança

Object

ProviderBase

ProtectedConfigurationProvider

Derivado

System.Configuration.DpapiProtectedConfigurationProvider

System.Configuration.RsaProtectedConfigurationProvider

Exemplos

O exemplo a seguir mostra como implementar um ProtectedConfigurationProviderpersonalizado.

Para poder configurar esse provedor, conforme mostrado no próximo trecho de configuração, você deve instalá-lo no GAC (Cache de Assembly Global). Para obter mais informações, consulte Implementando um provedor de configuração protegido.

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.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


        ' 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



        ' 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



        ' 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

End Namespace

O exemplo a seguir mostra como usar o ProtectedConfigurationProviderpersonalizado anterior.

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();
        }
    }
}

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


        ' 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



        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
    End Class
End Namespace

Comentários

Você pode criptografar seções de um arquivo de configuração para proteger informações confidenciais usadas pelo aplicativo. Isso melhora a segurança dificultando o acesso não autorizado, mesmo que um invasor obtenha acesso ao arquivo de configuração.

O .NET inclui dois provedores de configuração protegidos que podem ser usados para criptografar seções de um arquivo de configuração. A classe RsaProtectedConfigurationProvider usa o RSACryptoServiceProvider para criptografar seções de configuração. A classe DpapiProtectedConfigurationProvider usa a DPAPI (API de Proteção de Dados do Windows) para criptografar seções de configuração.

Você pode ter um requisito para criptografar informações confidenciais usando um algoritmo diferente dos provedores RSA ou DPAPI. Nesse caso, você pode criar seu próprio provedor de configuração protegida personalizada. O ProtectedConfigurationProvider é uma classe base abstrata da qual você deve herdar para criar seu próprio provedor de configuração protegida.

Se você usa um provedor padrão ou personalizado, deve garantir que ele esteja configurado com o elemento add na seção providers da seção de configuração configProtectedData. (Confira o próximo exemplo.)

Para obter detalhes, consulte Implementando um provedor de configuração protegido.

Construtores

Propriedades

Métodos

Aplica-se a

Confira também

• ProtectedConfigurationProviderCollection
• ProtectedConfiguration
• ProtectedConfigurationSection
• DpapiProtectedConfigurationProvider
• RsaProtectedConfigurationProvider
• criptografar informações de configuração usando de configuração protegida