SymmetricAlgorithm.LegalKeySizes Property

Definition

Namespace:

System.Security.Cryptography

Assembly:

System.Security.Cryptography.dll

Source:

SymmetricAlgorithm.cs

Gets the key sizes, in bits, that are supported by the symmetric algorithm.

public:
 virtual property cli::array <System::Security::Cryptography::KeySizes ^> ^ LegalKeySizes { cli::array <System::Security::Cryptography::KeySizes ^> ^ get(); };

public virtual System.Security.Cryptography.KeySizes[] LegalKeySizes { get; }

member this.LegalKeySizes : System.Security.Cryptography.KeySizes[]

Public Overridable ReadOnly Property LegalKeySizes As KeySizes()

Property Value

KeySizes[]

An array that contains the key sizes supported by the algorithm.

Examples

The following example shows the value of LegalKeySizes for the AES symmetric algorithm.

using System;
using System.Security.Cryptography;
namespace SymmetricAlgo
{
    class Program
    {
        static void Main(string[] args)
        {
            Aes aes = Aes.Create();
            Console.WriteLine("Aes ");
            KeySizes[] ks = aes.LegalKeySizes;
            foreach (KeySizes k in ks)
            {
                Console.WriteLine("\tLegal min key size = " + k.MinSize);
                Console.WriteLine("\tLegal max key size = " + k.MaxSize);
            }
            ks = aes.LegalBlockSizes;
            foreach (KeySizes k in ks)
            {
                Console.WriteLine("\tLegal min block size = " + k.MinSize);
                Console.WriteLine("\tLegal max block size = " + k.MaxSize);
            }
        }
    }
}
//This sample produces the following output:
//Aes
//        Legal min key size = 128
//        Legal max key size = 256
//        Legal min block size = 128
//        Legal max block size = 128

Imports System.Security.Cryptography


Class Program

    Shared Sub Main(ByVal args() As String)
        Dim aes As Aes = Aes.Create()
        Console.WriteLine("Aes ")
        Dim ks As KeySizes() = aes.LegalKeySizes
        Dim k As KeySizes
        For Each k In ks
            Console.WriteLine(vbTab + "Legal min key size = " & k.MinSize)
            Console.WriteLine(vbTab + "Legal max key size = " & k.MaxSize)
        Next k
        ks = aes.LegalBlockSizes

        For Each k In ks
            Console.WriteLine(vbTab + "Legal min block size = " & k.MinSize)
            Console.WriteLine(vbTab + "Legal max block size = " & k.MaxSize)
        Next k


    End Sub
End Class
'This sample produces the following output:
'Aes
'        Legal min key size = 128
'        Legal max key size = 256
'        Legal min block size = 128
'        Legal max block size = 128

Remarks

The symmetric algorithm supports only key sizes that match an entry in this array.

See also

• Cryptographic Services