KeySizes Class

Reference

Definition

Namespace:: System.Security.Cryptography

Assembly:: System.Security.Cryptography.Primitives.dll

Assembly:: System.Security.Cryptography.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Source:: KeySizes.cs

Source:: KeySizes.cs

Source:: KeySizes.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Determines the set of valid key sizes for the symmetric cryptographic algorithms.

public ref class KeySizes sealed

public sealed class KeySizes

[System.Runtime.InteropServices.ComVisible(true)]
public sealed class KeySizes

type KeySizes = class

[<System.Runtime.InteropServices.ComVisible(true)>]
type KeySizes = class

Public NotInheritable Class KeySizes

Inheritance: Object
KeySizes

Attributes: ComVisibleAttribute

Examples

The following example shows the use of members of the KeySizes class.


using namespace System;
using namespace System::Security::Cryptography;

namespace CryptographySample
{
    ref class KeySizesMembers
    {
    public:
        static void Work()
        {
            // Initializes a new instance of the KeySizes class 
            // with the specified key values.
            int minSize = 64;
            int maxSize = 1024;
            int skipSize = 64;
            KeySizes^ keySizes = 
                gcnew KeySizes(minSize, maxSize, skipSize);

            // Show the values of the keys.
            ShowKeys(gcnew array<KeySizes^>(1) {keySizes},
                "Custom Keys");
                 
            // Create a new symmetric algorithm and display its 
            // key values.
            Aes^ aes = Aes::Create();
            ShowKeys(aes->LegalKeySizes, aes->ToString());
            Console::WriteLine("aes.blocksize:{0}", 
                    aes->BlockSize);

            // Create a new RSA algorithm and display its key values.
            RSA^ rsa = RSA::Create();
            ShowKeys(rsa->LegalKeySizes, rsa->ToString());
            Console::WriteLine("RSA KeySize ="
                " {0}",
                    rsa->KeySize);

            Console::WriteLine("This sample completed successfully; " 
                   "press Enter to exit.");
            Console::ReadLine();
        }

    private:
        // Display specified KeySize properties to the console.
        static void ShowKeys(array <KeySizes^>^ keySizes,
            String^ objectName)
        {
            // Retrieve the first KeySizes in the array.
            KeySizes^ firstKeySize = keySizes[0];

            // Retrieve the minimum key size in bits.
            int minKeySize = firstKeySize->MinSize;

            // Retrieve the maximum key size in bits.
            int maxKeySize = firstKeySize->MaxSize;

            // Retrieve the interval between valid key size in bits.
            int skipKeySize = firstKeySize->SkipSize;

            Console::Write("\n KeySizes retrieved from the ");
            Console::WriteLine("{0} object.", objectName);
            Console::WriteLine("Minimum key size bits: {0}", 
                minKeySize);
            Console::WriteLine("Maximum key size bits: {0}", 
                maxKeySize);
            Console::WriteLine("Interval between key size bits: {0}", 
                skipKeySize);            
        }
    };
}

using namespace CryptographySample;

int main()
{
    KeySizesMembers::Work();
}
//
// This sample produces the following output:
//
// KeySizes retrieved from the Custom Keys object.
// Minimum key size bits: 64
// Maximum key size bits: 1024
// Interval between key size bits: 64
// 
// KeySizes retrieved from the 
//  System.Security.Cryptography.Aes object.
// Minimum key size bits: 128
// Maximum key size bits: 256
// Interval between key size bits: 64
// aes.blocksize:128
// 
// KeySizes retrieved from the
// System.Security.Cryptography.RSA object.
// Minimum key size bits: 512
// Maximum key size bits: 16384
// Interval between key size bits: 64
// RSA KeySize = 2048
// This sample completed successfully; press Enter to exit.

using System;
using System.Security.Cryptography;

namespace Contoso
{
    class KeySizesMembers
    {
        [STAThread]
        static void Main(string[] args)
        {
            // Initializes a new instance of the KeySizes class with the
            // specified key values.
            int minSize = 64;
            int maxSize = 1024;
            int skipSize = 64;
            KeySizes keySizes = new KeySizes(minSize, maxSize, skipSize);

            // Show the values of the keys.
            ShowKeys(new KeySizes[1]{keySizes}, "Custom Keys");

            // Create a new symmetric algorithm and display its key values.
            Aes aes = Aes.Create();
            ShowKeys(aes.LegalKeySizes, aes.ToString());
            Console.WriteLine("aes.blocksize:" + aes.BlockSize);

            // Create a new RSA algorithm and display its key values.
            RSA rsa = RSA.Create();
            ShowKeys(rsa.LegalKeySizes, rsa.ToString());
            Console.WriteLine("RSA KeySize = " + 
                rsa.KeySize);

            Console.WriteLine("This sample completed successfully; " +
                "press Enter to exit.");
            Console.ReadLine();
        }

        // Display specified KeySize properties to the console.
        private static void ShowKeys(KeySizes[] keySizes, string objectName)
        {
            // Retrieve the first KeySizes in the array.
            KeySizes firstKeySize = keySizes[0];

            // Retrieve the minimum key size in bits.
            int minKeySize = firstKeySize.MinSize;
                
            // Retrieve the maximum key size in bits.
            int maxKeySize = firstKeySize.MaxSize;
                
            // Retrieve the interval between valid key size in bits.
            int skipKeySize = firstKeySize.SkipSize;

            Console.Write("\n KeySizes retrieved from the ");
            Console.WriteLine(objectName + " object.");
            Console.WriteLine("Minimum key size bits: " + minKeySize);
            Console.WriteLine("Maximum key size bits: " + maxKeySize);
            Console.WriteLine("Interval between key size bits: " + 
                skipKeySize);
        }
    }
}
//
// This sample produces the following output:
//
// KeySizes retrieved from the Custom Keys object.
// Minimum key size bits: 64
// Maximum key size bits: 1024
// Interval between key size bits: 64
// 
// KeySizes retrieved from the System.Security.Cryptography.Aes
// object.
// Minimum key size bits: 128
// Maximum key size bits: 256
// Interval between key size bits: 64
// aes.blocksize:128
// 
// KeySizes retrieved from the
// System.Security.Cryptography.RSA object.
// Minimum key size bits: 512
// Maximum key size bits: 16384
// Interval between key size bits: 64
// RSA KeySize = 2048
// This sample completed successfully; press Enter to exit.

Imports System.Security.Cryptography

Public 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 = ""

        ' Initializes a new instance of the KeySizes class with the
        ' specified key values.
        Dim MinSize As Integer = 64
        Dim MaxSize As Integer = 1024
        Dim SkipSize As Integer = 64
        Dim keySizes As New KeySizes(MinSize, MaxSize, SkipSize)

        ' Show the values of the keys.
        ShowKeys(New KeySizes(0) {keySizes}, "Custom Keys")

        ' Create a new symmetric algorithm and display its key values.
        Dim aes As Aes = Aes.Create()
        WriteLine("aes.blocksize:" + aes.BlockSize.ToString())
        ShowKeys(aes.LegalKeySizes, aes.ToString())

        ' Create a new RSA algorithm and display its key values.
        Dim rsa As RSA = RSA.Create()
        WriteLine("RSA KeySize = " + _
            rsa.KeySize.ToString())
        ShowKeys(rsa.LegalKeySizes, rsa.ToString())

        ' Reset the cursor and conclude application.
        WriteLine("This sample completed successfully;" + _
            " press Exit to continue.")
        tbxOutput.Cursor = Cursors.Default
    End Sub

    ' Display specified KeySize properties to output textbox.
    Private Sub ShowKeys( _
        ByVal KeySizes() As KeySizes, _
        ByVal objectName As String)

        ' Retrieve the first KeySizes in the array.
        Dim firstKeySize As KeySizes = KeySizes(0)

        ' Retrieve the minimum key size in bits.
        Dim minKeySize As Integer = firstKeySize.MinSize

        ' Retrieve the maximum key size in bits.
        Dim maxKeySize As Integer = firstKeySize.MaxSize

        ' Retrieve the interval between valid key size in bits.
        Dim skipKeySize As Integer = firstKeySize.SkipSize

        WriteLine("KeySizes retrieved from the " + objectName + " object.")
        WriteLine("Minimum key size bits: " + minKeySize.ToString())
        WriteLine("Maximum key size bits: " + maxKeySize.ToString())
        WriteLine("Interval between key size bits: " + skipKeySize.ToString())
        WriteLine("")
    End Sub
    ' Display the message to the textbox with a carriage return and line feed.
    Private Sub WriteLine(ByVal message As String)
        tbxOutput.AppendText(message + vbCrLf)
    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
#Region " Windows Form Designer generated code "

    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 = "KeySizes"
        Me.Panel2.ResumeLayout(False)
        Me.Panel1.ResumeLayout(False)
        Me.ResumeLayout(False)

    End Sub

#End Region
End Class
'
' This sample produces the following output:
'
' KeySizes retrieved from the Custom Keys object.
' Minimum key size bits: 64
' Maximum key size bits: 1024
' Interval between key size bits: 64
' 
' aes.blocksize:128
' KeySizes retrieved from the System.Security.Cryptography.Aes
' object.
' Minimum key size bits: 128
' Maximum key size bits: 256
' Interval between key size bits: 64
' 
' RSA KeySize = 2048
' KeySizes retrieved from the
' System.Security.Cryptography.RSA object.
' Minimum key size bits: 512
' Maximum key size bits: 16384
' Interval between key size bits: 64
' 
' This sample completed successfully; press Exit to continue.

Constructors

KeySizes(Int32, Int32, Int32)

Initializes a new instance of the KeySizes class with the specified key values.

Properties

MaxSize	Specifies the maximum key size.
MinSize	Specifies the minimum key size.
SkipSize	Specifies the interval between valid key sizes.

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Applies to

Jaa