AsymmetricAlgorithm Klass

Definition

public ref class AsymmetricAlgorithm abstract : IDisposable

public abstract class AsymmetricAlgorithm : IDisposable

[System.Runtime.InteropServices.ComVisible(true)]
public abstract class AsymmetricAlgorithm : IDisposable

type AsymmetricAlgorithm = class
    interface IDisposable

[<System.Runtime.InteropServices.ComVisible(true)>]
type AsymmetricAlgorithm = class
    interface IDisposable

Public MustInherit Class AsymmetricAlgorithm
Implements IDisposable

Arv

Object

AsymmetricAlgorithm

Härledda

System.Security.Cryptography.DSA

System.Security.Cryptography.ECAlgorithm

System.Security.Cryptography.ECDiffieHellman

System.Security.Cryptography.ECDsa

System.Security.Cryptography.RSA

Attribut

ComVisibleAttribute

Implementeringar

IDisposable

Exempel

I följande kodexempel visas hur du implementerar en anpassad asymmetrisk algoritm som ärvts AsymmetricAlgorithm från klassen. Ytterligare en klass tillhandahålls för att visa hur du använder den anpassade klassen.

using System;
using System.Xml;
using System.Text;
using System.Security.Cryptography;
using System.Reflection;

[assembly: AssemblyKeyFile("CustomCrypto.snk")]
[assembly: AssemblyVersion("1.0.0.0")]
[assembly: CLSCompliant(true)]
namespace Contoso
{
    // Define a CustomCrypto class that inherits from the AsymmetricAlgorithm
    // class.
    public class CustomCrypto : 
        System.Security.Cryptography.AsymmetricAlgorithm
    {
        // Declare local member variables.
        private CspParameters cspParameters;
        private readonly KeySizes[] keySizes = {new KeySizes(8, 64, 8)};

        // Initialize a CustomCrypto with the default key size of 8.
        public CustomCrypto()
        {
            this.KeySize = 8;
        }

        // Initialize a CustomCrypto with the specified key size.
        public CustomCrypto(int keySize)
        {
            this.KeySize = keySize;
        }

        // Accessor function for keySizes member variable.
        public override KeySizes[] LegalKeySizes 
        { 
            get { return (KeySizes[])keySizes.Clone(); }
        }

        // Modify the KeySizeValue property inherited from the Asymmetric
        // class. Prior to setting the value, ensure it falls within the
        // range identified in the local keySizes member variable.
        public override int KeySize 
        {
            get { return KeySizeValue; }
            set
            {
                for (int i=0; i < keySizes.Length; i++)
                {
                    if (keySizes[i].SkipSize == 0) 
                    {
                        if (keySizes[i].MinSize == value)
                        {
                            KeySizeValue = value;
                            return;
                        }
                    }
                    else
                    {
                        for (int j = keySizes[i].MinSize;
                            j <= keySizes[i].MaxSize;
                            j += keySizes[i].SkipSize)
                        {
                            if (j == value)
                            {
                                KeySizeValue = value;
                                return;
                            }
                        }
                    }
                }

                // If the key does not fall within the range identified 
                // in the keySizes member variable, throw an exception.
                throw new CryptographicException("Invalid key size.");
            }
        }

        // Initialize the parameters with default values.
        public void InitializeParameters()
        {
            cspParameters = new CspParameters();
            cspParameters.ProviderName = "Contoso";
            cspParameters.KeyContainerName = "SecurityBin1";
            cspParameters.KeyNumber = 1;
            cspParameters.ProviderType = 2;
        }

        // Parse specified xmlString for values to populate the CspParams
        // Expected XML schema:
        //      <ProviderName></ProviderName>
        //      <KeyContainerName></KeyContainerName>
        //      <KeyNumber></KeyNumber>
        //      <ProviderType></ProviderType>
        public override void FromXmlString(string xmlString)
        {
            if (xmlString != null)
            {
                XmlDocument doc = new XmlDocument();
                doc.LoadXml(xmlString);
                XmlNode firstNode = doc.FirstChild;
                XmlNodeList nodeList;

                // Assemble parameters from values in each XML element.
                cspParameters = new CspParameters();

                // KeyContainerName is optional.
                nodeList = doc.GetElementsByTagName("KeyContainerName");
                string keyName = nodeList.Item(0).InnerText;
                if (keyName != null) 
                {
                    cspParameters.KeyContainerName = keyName;
                }

                // KeyNumber is optional.
                nodeList = doc.GetElementsByTagName("KeyNumber");
                string keyNumber = nodeList.Item(0).InnerText;
                if (keyNumber != null) 
                {
                    cspParameters.KeyNumber = Int32.Parse(keyNumber);
                }

                // ProviderName is optional.
                nodeList = doc.GetElementsByTagName("ProviderName");
                string providerName = nodeList.Item(0).InnerText;
                if (providerName != null) 
                {
                    cspParameters.ProviderName = providerName;
                }

                // ProviderType is optional.
                nodeList = doc.GetElementsByTagName("ProviderType");
                string providerType = nodeList.Item(0).InnerText;
                if (providerType != null) 
                {
                    cspParameters.ProviderType = Int32.Parse(providerType);
                }
            }
            else
            {
                throw new ArgumentNullException("xmlString");
            }
        }

        // Create an XML string representation of the parameters in the
        // current customCrypto object.
        public override string ToXmlString(bool includePrivateParameters)
        {
            string keyContainerName = "";
            string keyNumber = "";
            string providerName = "";
            string providerType = "";

            if (cspParameters != null)
            {
                keyContainerName = cspParameters.KeyContainerName;
                keyNumber = cspParameters.KeyNumber.ToString();
                providerName = cspParameters.ProviderName;
                providerType = cspParameters.ProviderType.ToString();
            }

            StringBuilder sb = new StringBuilder();
            sb.Append("<CustomCryptoKeyValue>");

            sb.Append("<KeyContainerName>");
            sb.Append(keyContainerName);
            sb.Append("</KeyContainerName>");

            sb.Append("<KeyNumber>");
            sb.Append(keyNumber);
            sb.Append("</KeyNumber>");

            sb.Append("<ProviderName>");
            sb.Append(providerName);
            sb.Append("</ProviderName>");

            sb.Append("<ProviderType>");
            sb.Append(providerType);
            sb.Append("</ProviderType>");

            sb.Append("</CustomCryptoKeyValue>");
            return(sb.ToString());
        }

        // Return the name for the key exchange algorithm.
        public override string KeyExchangeAlgorithm
        {
            get {return "RSA-PKCS1-KeyEx";}
        }

        // Retrieves the name of the signature alogrithm.
        // This example uses the SHA1 algorithm.
        // Due to collision problems with SHA1, Microsoft recommends SHA256 or better.
        public override string SignatureAlgorithm 
        {
            get {return "http://www.w3.org/2000/09/xmldsig#rsa-sha1";}
        }

        // Required member for implementing the AsymmetricAlgorithm class.
        protected override void Dispose(bool disposing) {}

        // Call the Create method using the CustomCrypto assembly name.
        // The create function attempts to create a CustomCrypto object using
        // the assembly name. This functionality requires modification of the
        // machine.config file. Add the following section to the configuration
        // element and modify the values of the cryptoClass to reflect what is
        // installed in your machines GAC.
        //        <cryptoClass CustomCrypto="Contoso.CustomCrypto, 
        //          CustomCrypto, 
        //          Culture=neutral, 
        //          PublicKeyToken=fdb9f9c4851028bf, 
        //          Version=1.0.1448.27640" />
        //      <nameEntry name="Contoso.CustomCrypto" class="CustomCrypto" />
        //      <nameEntry name="CustomCrypto" class="CustomCrypto" />
        new static public CustomCrypto Create() 
        {
            return Create("CustomCrypto");
        }

        // Create a CustomCrypto object by calling CrytoConfig's
        // CreateFromName method and casting the type to CustomCrypto.
        // The create function attempts to create a CustomCrypto object using
        // the assembly name. This functionality requires modification of the
        // machine.config file. Add the following section to the configuration
        // element and modify the values of the cryptoClass to reflect what is
        // installed in your machines GAC.
        //       <cryptoClass CustomCrypto="Contoso.CustomCrypto, 
        //         CustomCrypto, 
        //         Culture=neutral, 
        //         PublicKeyToken=fdb9f9c4851028bf, 
        //         Version=1.0.1448.27640" />
        //     <nameEntry name="Contoso.CustomCrypto" class="CustomCrypto" />
        //     <nameEntry name="CustomCrypto" class="CustomCrypto" />
        new static public CustomCrypto Create(String algorithmName) 
        {
            return (CustomCrypto) CryptoConfig.CreateFromName(algorithmName);
        }
    }
    class CustomCryptoImpl
    {
        [STAThread]
        static void Main(string[] args)
        {
            // Construct a CustomCrypto object and initialize its
            // CspParameters.
            CustomCrypto customCrypto = new CustomCrypto();
            customCrypto.InitializeParameters();

            // Display properties of the current customCrypto object.
            Console.WriteLine("*** CustomCrypto created with default " + 
                "parameters:");
            DisplayProperties(customCrypto);

            // Release all the resources used by this instance of 
            // CustomCrytpo.
            customCrypto.Clear();

            customCrypto = new CustomCrypto(64);
            // Create new parameters and set them by using the FromXmlString
            // method.
            string parameterXml = "<CustomCryptoKeyValue>";
            parameterXml += "<ProviderName>Contoso</ProviderName>";
            parameterXml += "<KeyContainerName>SecurityBin2";
            parameterXml += "</KeyContainerName>";
            parameterXml += "<KeyNumber>1</KeyNumber>";
            parameterXml += "<ProviderType>2</ProviderType>";
            parameterXml += "</CustomCryptoKeyValue>";
            customCrypto.FromXmlString(parameterXml);

            // Display the properties of a customCrypto object created with
            // custom parameters.
            Console.WriteLine("\n*** " + 
                "CustomCrypto created with custom parameters:");
            DisplayProperties(customCrypto);

            // Create an object by using the assembly name.
            try
            {
                CustomCrypto myCryptoA = CustomCrypto.Create("CustomCrypto");
                if (myCryptoA != null)
                {
                    Console.Write("\n*** " + 
                        "Successfully created CustomCrytpo from");
                    Console.WriteLine(" the Create method.");

                    DisplayProperties(myCryptoA);
                }
                else
                {
                    Console.Write("Unable to create CustomCrytpo from ");
                    Console.WriteLine(" the Create method.");
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            
            Console.WriteLine("This sample completed successfully; " +
                "press Enter to exit.");
            Console.ReadLine();
        }
        // Display the properties of the specified CustomCrypto object to the
        // console.
        public static void DisplayProperties(CustomCrypto customCrypto)
        {
            try
            {
                // Retrieve the class description for the customCrypto object.
                string classDescription = customCrypto.ToString();

                Console.WriteLine(classDescription);
                Console.Write("KeyExchangeAlgorithm: ");
                Console.WriteLine(customCrypto.KeyExchangeAlgorithm);
                Console.Write("SignatureAlgorithm: ");
                Console.WriteLine(customCrypto.SignatureAlgorithm);
                Console.WriteLine("KeySize: " + customCrypto.KeySize);
                Console.WriteLine("Parameters described in Xml format:");
                Console.WriteLine(customCrypto.ToXmlString(true));

                // Display the MinSize, MaxSize, and SkipSize properties of 
                // each KeySize item in the local keySizes member variable.
                KeySizes[] legalKeySizes = customCrypto.LegalKeySizes;
                if (legalKeySizes.Length > 0)
                {
                    for (int i=0; i < legalKeySizes.Length; i++)
                    {
                        Console.Write("Keysize" + i + " min, max, step: ");
                        Console.Write(legalKeySizes[i].MinSize + ", ");
                        Console.Write(legalKeySizes[i].MaxSize + ", ");
                        Console.WriteLine(legalKeySizes[i].SkipSize + ", ");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Caught unexpected exception: " + 
                    ex.ToString());
            }
        }
    }
}
//
// This sample produces the following output:
//
// *** CustomCrypto created with default parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 8
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// 
// *** CustomCrypto created with custom parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 64
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// Unable to create CustomCrytpo from  the Create method
// This sample completed successfully; press Exit to continue.

Imports System.Xml
Imports System.Text
Imports System.Security.Cryptography
Imports System.Reflection

<Assembly: AssemblyKeyFile("CustomCrypto.snk")> 
<Assembly: AssemblyVersion("1.0.0.0")> 
<Assembly: CLSCompliant(True)> 
Namespace Contoso
    ' Define a vbCustomCrypto class that inherits from the AsymmetricAlgorithm
    ' class.
    Class vbCustomCrypto
        Inherits System.Security.Cryptography.AsymmetricAlgorithm

        ' Declare local member variables.
        Private cspParameters As CspParameters
        Private ReadOnly keySizes() As keySizes = {New keySizes(8, 64, 8)}

        ' Initialize a vbCustomCrypto with the default key size of 8.
        Public Sub New()
            Me.KeySize = 8
        End Sub

        ' Initialize a vbCustomCrypto with the specified key size.
        Public Sub New(ByVal keySize As Integer)
            Me.KeySize = keySize
        End Sub

        ' Modify the KeySizeValue property inherited from the Asymmetric
        ' class. Prior to setting the value, ensure it falls within the
        ' range identified in the local keySizes member variable.
        Public Overrides Property KeySize() As Integer
            Get
                Return KeySizeValue
            End Get
            Set(ByVal Value As Integer)
                For i As Int16 = 0 To keySizes.Length - 1 Step i
                    If (keySizes(i).SkipSize.Equals(0)) Then
                        If (keySizes(i).MinSize.Equals(Value)) Then
                            KeySizeValue = Value
                            Return
                        End If
                    Else
                        For j As Integer = keySizes(i).MinSize _
                            To keySizes(i).MaxSize _
                            Step keySizes(i).SkipSize
                            If (j.Equals(Value)) Then
                                KeySizeValue = Value
                                Return
                            End If
                        Next
                    End If
                Next
                ' If the key does not fall within the range identified 
                ' in the keySizes member variable, throw an exception.
                Throw New CryptographicException("Invalid key size.")
            End Set
        End Property
        ' Accessor function for keySizes member variable.
        public Overrides Readonly Property LegalKeySizes as KeySizes()
            Get
                Return keySizes
            End Get
        End Property
        ' Initialize the parameters with default values.
        Public Sub InitializeParameters()
            cspParameters = New CspParameters
            cspParameters.ProviderName = "Contoso"
            cspParameters.KeyContainerName = "SecurityBin1"
            cspParameters.KeyNumber = 1
            cspParameters.ProviderType = 2
        End Sub

        ' Parse specified xmlString for values to populate the CspParams
        ' Expected XML schema:
        '      <ProviderName></ProviderName>
        '      <KeyContainerName></KeyContainerName>
        '      <KeyNumber></KeyNumber>
        '      <ProviderType></ProviderType>
        Public Overrides Sub FromXmlString(ByVal xmlString As String)
            If Not xmlString Is Nothing Then
                Dim doc As New XmlDocument
                doc.LoadXml(xmlString)
                Dim firstNode As XmlNode = doc.FirstChild
                Dim nodeList As XmlNodeList

                ' Assemble parameters from values in each XML element.
                cspParameters = New CspParameters

                ' KeyContainerName is optional.
                nodeList = doc.GetElementsByTagName("KeyContainerName")
                Dim keyName As String = nodeList.Item(0).InnerText
                If Not keyName Is Nothing Then
                    cspParameters.KeyContainerName = keyName
                End If

                ' KeyNumber is optional.
                nodeList = doc.GetElementsByTagName("KeyNumber")
                Dim keyNumber As String = nodeList.Item(0).InnerText
                If Not keyNumber Is Nothing Then
                    cspParameters.KeyNumber = Int32.Parse(keyNumber)
                End If

                ' ProviderName is optional.
                nodeList = doc.GetElementsByTagName("ProviderName")
                Dim providerName As String = nodeList.Item(0).InnerText
                If Not providerName Is Nothing Then
                    cspParameters.ProviderName = providerName
                End If

                ' ProviderType is optional.
                nodeList = doc.GetElementsByTagName("ProviderType")
                Dim providerType As String = nodeList.Item(0).InnerText
                If Not providerType Is Nothing Then
                    cspParameters.ProviderType = Int32.Parse(providerType)
                End If
            Else
                Throw New ArgumentNullException("xmlString")
            End If
        End Sub

        ' Create an XML string representation of the parameters in the current
        ' vbCustomCrypto object.
        Public Overrides Function ToXmlString( _
            ByVal includePrivateParameters As Boolean) As String

            Dim keyContainerName As String = ""
            Dim keyNumber As String = ""
            Dim providerName As String = ""
            Dim providerType As String = ""

            If Not cspParameters Is Nothing Then
                keyContainerName = cspParameters.KeyContainerName
                keyNumber = cspParameters.KeyNumber.ToString()
                providerName = cspParameters.ProviderName
                providerType = cspParameters.ProviderType.ToString()
            End If

            Dim xmlBuilder As New StringBuilder
            xmlBuilder.Append("<CustomCryptoKeyValue>")

            xmlBuilder.Append("<KeyContainerName>")
            xmlBuilder.Append(keyContainerName)
            xmlBuilder.Append("</KeyContainerName>")

            xmlBuilder.Append("<KeyNumber>")
            xmlBuilder.Append(keyNumber)
            xmlBuilder.Append("</KeyNumber>")

            xmlBuilder.Append("<ProviderName>")
            xmlBuilder.Append(providerName)
            xmlBuilder.Append("</ProviderName>")

            xmlBuilder.Append("<ProviderType>")
            xmlBuilder.Append(providerType)
            xmlBuilder.Append("</ProviderType>")

            xmlBuilder.Append("</CustomCryptoKeyValue>")
            Return (xmlBuilder.ToString())
        End Function

        ' Return the name for the key exchange algorithm.
        Public Overrides ReadOnly Property KeyExchangeAlgorithm() As String
            Get
                Return "RSA-PKCS1-KeyEx"
            End Get
        End Property

        ' Retrieves the name of the signature alogrithm.
        ' This example uses the SHA1 algorithm.
        ' Due to collision problems with SHA1, Microsoft recommends SHA256 or better.
        Public Overrides ReadOnly Property SignatureAlgorithm() As String
            Get
                Return "http://www.w3.org/2000/09/xmldsig#rsa-sha1"
            End Get
        End Property

        ' Required member for implementing the AsymmetricAlgorithm class.
        Protected Overrides Sub Dispose(ByVal disposing As Boolean)

        End Sub

        ' The create function attempts to create a vbCustomCrypto object using
        ' the assembly name. This functionality requires modification of the
        ' machine.config file. Add the following section to the configuration
        ' element and modify the values of the cryptoClass to reflect what is
        ' installed in your machines GAC.
        '          <cryptoClass vbCustomCrypto="Contoso.vbCustomCrypto, 
        '            vbCustomCrypto, 
        '            Culture=neutral, 
        '            PublicKeyToken=fdb9f9c4851028bf, 
        '            Version=1.0.1448.27640" />
        '        <nameEntry name="Contoso.vbCustomCrypto" 
        '                   class="vbCustomCrypto" />
        '        <nameEntry name="vbCustomCrypto" class="vbCustomCrypto" />
        Public Shadows Function Create() As vbCustomCrypto
            Return Create("vbCustomCrypto")
        End Function

        ' Create a CustomCrypto object by calling CrytoConfig's
        ' CreateFromName method and casting the type to CustomCrypto.
        ' The create function attempts to create a vbCustomCrypto object using
        ' the assembly name. This functionality requires modification of the
        ' machine.config file. Add the following section to the configuration
        ' element and modify the values of the cryptoClass to reflect what is
        ' installed in your machines GAC.
        '          <cryptoClass vbCustomCrypto="Contoso.vbCustomCrypto, 
        '            vbCustomCrypto, 
        '            Culture=neutral, 
        '            PublicKeyToken=fdb9f9c4851028bf, 
        '            Version=1.0.1448.27640" />
        '        <nameEntry name="Contoso.vbCustomCrypto" 
        '                   class="vbCustomCrypto" />
        '        <nameEntry name="vbCustomCrypto" class="vbCustomCrypto" />
        Public Shadows Function Create( _
            ByVal algorithmName As String) As vbCustomCrypto

            Return CType( _
                CryptoConfig.CreateFromName(algorithmName), _
                vbCustomCrypto)

        End Function
    End Class
    Class Form1
        Inherits System.Windows.Forms.Form

        ' Event handler for Run button.
        Private Sub Button1_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button1.Click

            tbxOutput.Cursor = Cursors.WaitCursor
            tbxOutput.Text = ""

            ' Construct a CustomCrypto object and initialize its
            ' CspParameters.
            Dim customCrypto As New Contoso.vbCustomCrypto
            customCrypto.InitializeParameters()

            ' Display properties of the current vbCustomCrypto object.
            WriteLine("*** CustomCrypto created with default parameters:")
            DisplayProperties(customCrypto)

            ' Release all the resources used by this instance of CustomCrytpo.
            customCrypto.Clear()

            customCrypto = New Contoso.vbCustomCrypto(64)
            ' Create new parameters and set them by using the
            ' FromXmlString method.
            Dim parameterXml As String = "<CustomCryptoKeyValue>"
            parameterXml += "<ProviderName>Contoso</ProviderName>"
            parameterXml += "<KeyContainerName>SecurityBin2"
            parameterXml += "</KeyContainerName>"
            parameterXml += "<KeyNumber>1</KeyNumber>"
            parameterXml += "<ProviderType>2</ProviderType>"
            parameterXml += "</CustomCryptoKeyValue>"
            customCrypto.FromXmlString(parameterXml)

            ' Display the properties of a customCrypto object created with
            ' custom parameters.
            WriteLine(vbCrLf + "*** " + _
                "CustomCrypto created with custom parameters:")
            DisplayProperties(customCrypto)

            ' Create an object by using the assembly name.
            Try
                Dim createdCrypto As Contoso.vbCustomCrypto
                createdCrypto = customCrypto.Create("vbCustomCrypto")

                If (Not createdCrypto Is Nothing) Then
                    Write(vbCrLf + "*** Successfully created vbCustomCrytpo ")
                    WriteLine("from the Create method.")

                    DisplayProperties(createdCrypto)
                Else
                    Write("Unable to create CustomCrytpo from ")
                    WriteLine(" the Create method.")
                End If
            Catch ex As Exception
                WriteLine(ex.ToString())
            End Try

            ' Align interface and conclude application.
            WriteLine("This sample completed successfully;" + _
                " press Exit to continue.")

            ' Reset the cursor.
            tbxOutput.Cursor = Cursors.Default
        End Sub
        ' Display the properties of the specified CustomCrypto object to
        ' the output texbox.
        Public Sub DisplayProperties( _
            ByVal customCrypto As Contoso.vbCustomCrypto)

            Try
                ' Retrieve the class description for the customCrypto object.
                Dim classDescription As String = customCrypto.ToString()

                WriteLine(classDescription)
                WriteLine("KeyExchangeAlgorithm: " + _
                    customCrypto.KeyExchangeAlgorithm)
                WriteLine("SignatureAlgorithm: " + _
                    customCrypto.SignatureAlgorithm)
                WriteLine("KeySize: " + customCrypto.KeySize.ToString())
                WriteLine("Parameters described in Xml format:")
                WriteLine(customCrypto.ToXmlString(True))

                ' Display the MinSize, MaxSize, and SkipSize properties of 
                ' each KeySize item in the local keySizes member variable.
                Dim legalKeySizes() As KeySizes = customCrypto.LegalKeySizes
                If (legalKeySizes.Length > 0) Then
                    For i As Integer = 0 To legalKeySizes.Length - 1 Step 1
                        Write("Keysize" + i.ToString() + " min, max, step: ")
                        Write(legalKeySizes(i).MinSize.ToString() + ", ")
                        Write(legalKeySizes(i).MaxSize.ToString() + ", ")
                        Write(legalKeySizes(i).SkipSize.ToString() + ", ")
                        WriteLine("")
                    Next
                End If
            Catch ex As Exception
                WriteLine("Caught unexpected exception: " + ex.ToString())
            End Try
        End Sub
        ' Write the specified message and carriage return to the output
        ' textbox.
        Private Sub WriteLine(ByVal message As String)
            tbxOutput.AppendText(message + vbCrLf)
        End Sub
        ' Write the specified message to the output textbox.
        Private Sub Write(ByVal message As String)
            tbxOutput.AppendText(message)
        End Sub
        ' Event handler for Exit button.
        Private Sub Button2_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button2.Click

            Application.Exit()
        End Sub


        Public Sub New()
            MyBase.New()

            'This call is required by the Windows Form Designer.
            InitializeComponent()

            'Add any initialization after the InitializeComponent() call

        End Sub

        'Form overrides dispose to clean up the component list.
        Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
            If disposing Then
                If Not (components Is Nothing) Then
                    components.Dispose()
                End If
            End If
            MyBase.Dispose(disposing)
        End Sub

        'Required by the Windows Form Designer
        Private components As System.ComponentModel.IContainer

        'NOTE: The following procedure is required by the Windows Form 
        'Designer. It can be modified using the Windows Form Designer. 
        'Do not modify it using the code editor.
        Friend WithEvents Panel2 As System.Windows.Forms.Panel
        Friend WithEvents Panel1 As System.Windows.Forms.Panel
        Friend WithEvents Button1 As System.Windows.Forms.Button
        Friend WithEvents Button2 As System.Windows.Forms.Button
        Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox
        <System.Diagnostics.DebuggerStepThrough()> _
        Private Sub InitializeComponent()
            Me.Panel2 = New System.Windows.Forms.Panel
            Me.Button1 = New System.Windows.Forms.Button
            Me.Button2 = New System.Windows.Forms.Button
            Me.Panel1 = New System.Windows.Forms.Panel
            Me.tbxOutput = New System.Windows.Forms.RichTextBox
            Me.Panel2.SuspendLayout()
            Me.Panel1.SuspendLayout()
            Me.SuspendLayout()
            '
            'Panel2
            '
            Me.Panel2.Controls.Add(Me.Button1)
            Me.Panel2.Controls.Add(Me.Button2)
            Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom
            Me.Panel2.DockPadding.All = 20
            Me.Panel2.Location = New System.Drawing.Point(0, 320)
            Me.Panel2.Name = "Panel2"
            Me.Panel2.Size = New System.Drawing.Size(616, 64)
            Me.Panel2.TabIndex = 1
            '
            'Button1
            '
            Me.Button1.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button1.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button1.Location = New System.Drawing.Point(446, 20)
            Me.Button1.Name = "Button1"
            Me.Button1.Size = New System.Drawing.Size(75, 24)
            Me.Button1.TabIndex = 2
            Me.Button1.Text = "&Run"
            '
            'Button2
            '
            Me.Button2.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button2.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button2.Location = New System.Drawing.Point(521, 20)
            Me.Button2.Name = "Button2"
            Me.Button2.Size = New System.Drawing.Size(75, 24)
            Me.Button2.TabIndex = 3
            Me.Button2.Text = "E&xit"
            '
            'Panel1
            '
            Me.Panel1.Controls.Add(Me.tbxOutput)
            Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill
            Me.Panel1.DockPadding.All = 20
            Me.Panel1.Location = New System.Drawing.Point(0, 0)
            Me.Panel1.Name = "Panel1"
            Me.Panel1.Size = New System.Drawing.Size(616, 320)
            Me.Panel1.TabIndex = 2
            '
            'tbxOutput
            '
            Me.tbxOutput.AccessibleDescription = _
                "Displays output from application."
            Me.tbxOutput.AccessibleName = "Output textbox."
            Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill
            Me.tbxOutput.Location = New System.Drawing.Point(20, 20)
            Me.tbxOutput.Name = "tbxOutput"
            Me.tbxOutput.Size = New System.Drawing.Size(576, 280)
            Me.tbxOutput.TabIndex = 1
            Me.tbxOutput.Text = "Click the Run button to run the application."
            '
            'Form1
            '
            Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
            Me.ClientSize = New System.Drawing.Size(616, 384)
            Me.Controls.Add(Me.Panel1)
            Me.Controls.Add(Me.Panel2)
            Me.Name = "Form1"
            Me.Text = "AsymmetricAlgorithm"
            Me.Panel2.ResumeLayout(False)
            Me.Panel1.ResumeLayout(False)
            Me.ResumeLayout(False)

        End Sub

    End Class
End Namespace
'
' This sample produces the following output:
'
' *** CustomCrypto created with default parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 8
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' 
' *** CustomCrypto created with custom parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 64
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' Unable to create CustomCrytpo from  the Create method
' This sample completed successfully; press Enter to exit.

Här är ytterligare en klass som visar hur du använder den anpassade klassen.

    class CustomCryptoImpl
    {
        [STAThread]
        static void Main(string[] args)
        {
            // Construct a CustomCrypto object and initialize its
            // CspParameters.
            CustomCrypto customCrypto = new CustomCrypto();
            customCrypto.InitializeParameters();

            // Display properties of the current customCrypto object.
            Console.WriteLine("*** CustomCrypto created with default " + 
                "parameters:");
            DisplayProperties(customCrypto);

            // Release all the resources used by this instance of 
            // CustomCrytpo.
            customCrypto.Clear();

            customCrypto = new CustomCrypto(64);
            // Create new parameters and set them by using the FromXmlString
            // method.
            string parameterXml = "<CustomCryptoKeyValue>";
            parameterXml += "<ProviderName>Contoso</ProviderName>";
            parameterXml += "<KeyContainerName>SecurityBin2";
            parameterXml += "</KeyContainerName>";
            parameterXml += "<KeyNumber>1</KeyNumber>";
            parameterXml += "<ProviderType>2</ProviderType>";
            parameterXml += "</CustomCryptoKeyValue>";
            customCrypto.FromXmlString(parameterXml);

            // Display the properties of a customCrypto object created with
            // custom parameters.
            Console.WriteLine("\n*** " + 
                "CustomCrypto created with custom parameters:");
            DisplayProperties(customCrypto);

            // Create an object by using the assembly name.
            try
            {
                CustomCrypto myCryptoA = CustomCrypto.Create("CustomCrypto");
                if (myCryptoA != null)
                {
                    Console.Write("\n*** " + 
                        "Successfully created CustomCrytpo from");
                    Console.WriteLine(" the Create method.");

                    DisplayProperties(myCryptoA);
                }
                else
                {
                    Console.Write("Unable to create CustomCrytpo from ");
                    Console.WriteLine(" the Create method.");
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            
            Console.WriteLine("This sample completed successfully; " +
                "press Enter to exit.");
            Console.ReadLine();
        }
        // Display the properties of the specified CustomCrypto object to the
        // console.
        public static void DisplayProperties(CustomCrypto customCrypto)
        {
            try
            {
                // Retrieve the class description for the customCrypto object.
                string classDescription = customCrypto.ToString();

                Console.WriteLine(classDescription);
                Console.Write("KeyExchangeAlgorithm: ");
                Console.WriteLine(customCrypto.KeyExchangeAlgorithm);
                Console.Write("SignatureAlgorithm: ");
                Console.WriteLine(customCrypto.SignatureAlgorithm);
                Console.WriteLine("KeySize: " + customCrypto.KeySize);
                Console.WriteLine("Parameters described in Xml format:");
                Console.WriteLine(customCrypto.ToXmlString(true));

                // Display the MinSize, MaxSize, and SkipSize properties of 
                // each KeySize item in the local keySizes member variable.
                KeySizes[] legalKeySizes = customCrypto.LegalKeySizes;
                if (legalKeySizes.Length > 0)
                {
                    for (int i=0; i < legalKeySizes.Length; i++)
                    {
                        Console.Write("Keysize" + i + " min, max, step: ");
                        Console.Write(legalKeySizes[i].MinSize + ", ");
                        Console.Write(legalKeySizes[i].MaxSize + ", ");
                        Console.WriteLine(legalKeySizes[i].SkipSize + ", ");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Caught unexpected exception: " + 
                    ex.ToString());
            }
        }
    }
}
//
// This sample produces the following output:
//
// *** CustomCrypto created with default parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 8
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// 
// *** CustomCrypto created with custom parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 64
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// Unable to create CustomCrytpo from  the Create method
// This sample completed successfully; press Exit to continue.

    Class Form1
        Inherits System.Windows.Forms.Form

        ' Event handler for Run button.
        Private Sub Button1_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button1.Click

            tbxOutput.Cursor = Cursors.WaitCursor
            tbxOutput.Text = ""

            ' Construct a CustomCrypto object and initialize its
            ' CspParameters.
            Dim customCrypto As New Contoso.vbCustomCrypto
            customCrypto.InitializeParameters()

            ' Display properties of the current vbCustomCrypto object.
            WriteLine("*** CustomCrypto created with default parameters:")
            DisplayProperties(customCrypto)

            ' Release all the resources used by this instance of CustomCrytpo.
            customCrypto.Clear()

            customCrypto = New Contoso.vbCustomCrypto(64)
            ' Create new parameters and set them by using the
            ' FromXmlString method.
            Dim parameterXml As String = "<CustomCryptoKeyValue>"
            parameterXml += "<ProviderName>Contoso</ProviderName>"
            parameterXml += "<KeyContainerName>SecurityBin2"
            parameterXml += "</KeyContainerName>"
            parameterXml += "<KeyNumber>1</KeyNumber>"
            parameterXml += "<ProviderType>2</ProviderType>"
            parameterXml += "</CustomCryptoKeyValue>"
            customCrypto.FromXmlString(parameterXml)

            ' Display the properties of a customCrypto object created with
            ' custom parameters.
            WriteLine(vbCrLf + "*** " + _
                "CustomCrypto created with custom parameters:")
            DisplayProperties(customCrypto)

            ' Create an object by using the assembly name.
            Try
                Dim createdCrypto As Contoso.vbCustomCrypto
                createdCrypto = customCrypto.Create("vbCustomCrypto")

                If (Not createdCrypto Is Nothing) Then
                    Write(vbCrLf + "*** Successfully created vbCustomCrytpo ")
                    WriteLine("from the Create method.")

                    DisplayProperties(createdCrypto)
                Else
                    Write("Unable to create CustomCrytpo from ")
                    WriteLine(" the Create method.")
                End If
            Catch ex As Exception
                WriteLine(ex.ToString())
            End Try

            ' Align interface and conclude application.
            WriteLine("This sample completed successfully;" + _
                " press Exit to continue.")

            ' Reset the cursor.
            tbxOutput.Cursor = Cursors.Default
        End Sub
        ' Display the properties of the specified CustomCrypto object to
        ' the output texbox.
        Public Sub DisplayProperties( _
            ByVal customCrypto As Contoso.vbCustomCrypto)

            Try
                ' Retrieve the class description for the customCrypto object.
                Dim classDescription As String = customCrypto.ToString()

                WriteLine(classDescription)
                WriteLine("KeyExchangeAlgorithm: " + _
                    customCrypto.KeyExchangeAlgorithm)
                WriteLine("SignatureAlgorithm: " + _
                    customCrypto.SignatureAlgorithm)
                WriteLine("KeySize: " + customCrypto.KeySize.ToString())
                WriteLine("Parameters described in Xml format:")
                WriteLine(customCrypto.ToXmlString(True))

                ' Display the MinSize, MaxSize, and SkipSize properties of 
                ' each KeySize item in the local keySizes member variable.
                Dim legalKeySizes() As KeySizes = customCrypto.LegalKeySizes
                If (legalKeySizes.Length > 0) Then
                    For i As Integer = 0 To legalKeySizes.Length - 1 Step 1
                        Write("Keysize" + i.ToString() + " min, max, step: ")
                        Write(legalKeySizes(i).MinSize.ToString() + ", ")
                        Write(legalKeySizes(i).MaxSize.ToString() + ", ")
                        Write(legalKeySizes(i).SkipSize.ToString() + ", ")
                        WriteLine("")
                    Next
                End If
            Catch ex As Exception
                WriteLine("Caught unexpected exception: " + ex.ToString())
            End Try
        End Sub
        ' Write the specified message and carriage return to the output
        ' textbox.
        Private Sub WriteLine(ByVal message As String)
            tbxOutput.AppendText(message + vbCrLf)
        End Sub
        ' Write the specified message to the output textbox.
        Private Sub Write(ByVal message As String)
            tbxOutput.AppendText(message)
        End Sub
        ' Event handler for Exit button.
        Private Sub Button2_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button2.Click

            Application.Exit()
        End Sub


        Public Sub New()
            MyBase.New()

            'This call is required by the Windows Form Designer.
            InitializeComponent()

            'Add any initialization after the InitializeComponent() call

        End Sub

        'Form overrides dispose to clean up the component list.
        Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
            If disposing Then
                If Not (components Is Nothing) Then
                    components.Dispose()
                End If
            End If
            MyBase.Dispose(disposing)
        End Sub

        'Required by the Windows Form Designer
        Private components As System.ComponentModel.IContainer

        'NOTE: The following procedure is required by the Windows Form 
        'Designer. It can be modified using the Windows Form Designer. 
        'Do not modify it using the code editor.
        Friend WithEvents Panel2 As System.Windows.Forms.Panel
        Friend WithEvents Panel1 As System.Windows.Forms.Panel
        Friend WithEvents Button1 As System.Windows.Forms.Button
        Friend WithEvents Button2 As System.Windows.Forms.Button
        Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox
        <System.Diagnostics.DebuggerStepThrough()> _
        Private Sub InitializeComponent()
            Me.Panel2 = New System.Windows.Forms.Panel
            Me.Button1 = New System.Windows.Forms.Button
            Me.Button2 = New System.Windows.Forms.Button
            Me.Panel1 = New System.Windows.Forms.Panel
            Me.tbxOutput = New System.Windows.Forms.RichTextBox
            Me.Panel2.SuspendLayout()
            Me.Panel1.SuspendLayout()
            Me.SuspendLayout()
            '
            'Panel2
            '
            Me.Panel2.Controls.Add(Me.Button1)
            Me.Panel2.Controls.Add(Me.Button2)
            Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom
            Me.Panel2.DockPadding.All = 20
            Me.Panel2.Location = New System.Drawing.Point(0, 320)
            Me.Panel2.Name = "Panel2"
            Me.Panel2.Size = New System.Drawing.Size(616, 64)
            Me.Panel2.TabIndex = 1
            '
            'Button1
            '
            Me.Button1.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button1.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button1.Location = New System.Drawing.Point(446, 20)
            Me.Button1.Name = "Button1"
            Me.Button1.Size = New System.Drawing.Size(75, 24)
            Me.Button1.TabIndex = 2
            Me.Button1.Text = "&Run"
            '
            'Button2
            '
            Me.Button2.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button2.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button2.Location = New System.Drawing.Point(521, 20)
            Me.Button2.Name = "Button2"
            Me.Button2.Size = New System.Drawing.Size(75, 24)
            Me.Button2.TabIndex = 3
            Me.Button2.Text = "E&xit"
            '
            'Panel1
            '
            Me.Panel1.Controls.Add(Me.tbxOutput)
            Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill
            Me.Panel1.DockPadding.All = 20
            Me.Panel1.Location = New System.Drawing.Point(0, 0)
            Me.Panel1.Name = "Panel1"
            Me.Panel1.Size = New System.Drawing.Size(616, 320)
            Me.Panel1.TabIndex = 2
            '
            'tbxOutput
            '
            Me.tbxOutput.AccessibleDescription = _
                "Displays output from application."
            Me.tbxOutput.AccessibleName = "Output textbox."
            Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill
            Me.tbxOutput.Location = New System.Drawing.Point(20, 20)
            Me.tbxOutput.Name = "tbxOutput"
            Me.tbxOutput.Size = New System.Drawing.Size(576, 280)
            Me.tbxOutput.TabIndex = 1
            Me.tbxOutput.Text = "Click the Run button to run the application."
            '
            'Form1
            '
            Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
            Me.ClientSize = New System.Drawing.Size(616, 384)
            Me.Controls.Add(Me.Panel1)
            Me.Controls.Add(Me.Panel2)
            Me.Name = "Form1"
            Me.Text = "AsymmetricAlgorithm"
            Me.Panel2.ResumeLayout(False)
            Me.Panel1.ResumeLayout(False)
            Me.ResumeLayout(False)

        End Sub

    End Class
End Namespace
'
' This sample produces the following output:
'
' *** CustomCrypto created with default parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 8
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' 
' *** CustomCrypto created with custom parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 64
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' Unable to create CustomCrytpo from  the Create method
' This sample completed successfully; press Enter to exit.

Kommentarer

Asymmetriska kryptografiska algoritmer, även kallade algoritmer för offentlig nyckel, kräver att både avsändare och mottagare har ett par relaterade nycklar: en privat nyckel och en offentlig nyckel. Båda nycklarna är unika för entiteten. Den offentliga nyckeln kan göras tillgänglig för vem som helst. den här nyckeln används för att koda data som skickas till en mottagare. Den privata nyckeln måste hållas privat av mottagaren. Den här nyckeln används för avkodning av meddelanden som kodas med mottagarens offentliga nyckel. Klassen RSACryptoServiceProvider är en implementering av en algoritm för offentlig nyckel. En djupgående diskussion om kryptering och algoritmer för offentliga nycklar finns i avsnittet "Public-Key Encryption" i Cryptographic Services. Information om hur du använder verktyget Starkt namn (Sn.exe) för att skapa nyckelpar finns i Så här skapar du ett Public-Private nyckelpar.

Du kan använda offentliga nyckelsystem för att skapa digitala signaturer. Digitala signaturer används för att skydda dataintegriteten. Om du till exempel vill använda ett offentligt nyckelsystem för att signera ett meddelande digitalt använder avsändaren först en hash-funktion för meddelandet för att skapa en meddelandesammandrag. Avsändaren krypterar sedan meddelandets sammandrag med avsändarens privata nyckel för att skapa avsändarens personliga signatur. När meddelandet och signaturen tas emot dekrypterar mottagaren signaturen med avsändarens offentliga nyckel för att återställa meddelandets sammandrag och hashar meddelandet med samma hashalgoritm som avsändaren använde. Om meddelandet sammanfattas som mottagaren beräknar matchar meddelandets sammandrag som tagits emot från avsändaren kan mottagaren anta att meddelandet inte har ändrats under överföringen. Observera att vem som helst kan verifiera en signatur eftersom avsändarens offentliga nyckel är allmänt känd. Den här tekniken behåller inte meddelandets hemlighetsmakeri. för att meddelandet ska vara hemligt måste det också krypteras.

.NET innehåller följande klasser som implementerar algoritmer för digitala signaturer: DSACryptoServiceProvider, RSACryptoServiceProvider, ECDsa (basklass) och ECDsaCng.

Namnområdet System.Security.Cryptography tillhandahåller endast konkreta klasser för RSA och DSA .

Information om hur du använder RSA-algoritmen för att kryptera och dekryptera XML-data och skapa och verifiera digitala XML-signaturer finns i följande artiklar:

• Anvisningar: Kryptera XML-element med asymmetriska nycklar

• Anvisningar: Dekryptera XML-element med asymmetriska nycklar

• Anvisningar: Signera XML-dokument med digitala signaturer

• Gör så här: Verifiera digitala signaturer för XML-dokument

Se även

• Kryptografiska tjänster
• Gör så här: Skapa ett offentligt/privat nyckelpar