ECDsaCng Class

 

Provides a Cryptography Next Generation (CNG) implementation of the Elliptic Curve Digital Signature Algorithm (ECDSA).

Namespace:   System.Security.Cryptography
Assembly:  System.Core (in System.Core.dll)


<HostProtectionAttribute(SecurityAction.LinkDemand, MayLeakOnAbort := True)>
Public NotInheritable Class ECDsaCng
	Inherits ECDsa

NameDescription
System_CAPS_pubmethodECDsaCng()

Initializes a new instance of the ECDsaCng class with a random key pair.

System_CAPS_pubmethodECDsaCng(CngKey)

Initializes a new instance of the ECDsaCng class by using the specified CngKey object.

System_CAPS_pubmethodECDsaCng(ECCurve)

Initializes a new instance of the ECDsaCng class whose public/private key pair is generated over the specified curve.

System_CAPS_pubmethodECDsaCng(Int32)

Initializes a new instance of the ECDsaCng class with a random key pair, using the specified key size.

NameDescription
System_CAPS_pubpropertyHashAlgorithm

Gets or sets the hash algorithm to use when signing and verifying data.

System_CAPS_pubpropertyKey

Gets or sets the key to use when signing and verifying data.

System_CAPS_pubpropertyKeyExchangeAlgorithm

Gets the name of the key exchange algorithm.(Inherited from ECDsa.)

System_CAPS_pubpropertyKeySize

Gets or sets the size, in bits, of the key modulus used by the asymmetric algorithm.(Inherited from AsymmetricAlgorithm.)

System_CAPS_pubpropertyLegalKeySizes

Gets the key sizes that are supported by the asymmetric algorithm.(Inherited from AsymmetricAlgorithm.)

System_CAPS_pubpropertySignatureAlgorithm

Gets the name of the signature algorithm.(Inherited from ECDsa.)

NameDescription
System_CAPS_pubmethodClear()

Releases all resources used by the AsymmetricAlgorithm class.(Inherited from AsymmetricAlgorithm.)

System_CAPS_pubmethodDispose()

Releases all resources used by the current instance of the AsymmetricAlgorithm class.(Inherited from AsymmetricAlgorithm.)

System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodExportExplicitParameters(Boolean)

Exports the key and explicit curve parameters used by the Elliptic curve cryptography (ECC) object into an ECParameters object. (Overrides ECDsa.ExportExplicitParameters(Boolean).)

System_CAPS_pubmethodExportParameters(Boolean)

Exports the key used by the Elliptic curve cryptography (ECC) object into an ECParameters object. If the key was created as a named curve, the Curve field contains named curve parameters; otherwise, it contains explicit parameters.(Overrides ECDsa.ExportParameters(Boolean).)

System_CAPS_pubmethodFromXmlString(String)

This method is not implemented.(Overrides AsymmetricAlgorithm.FromXmlString(String).)

System_CAPS_pubmethodFromXmlString(String, ECKeyXmlFormat)

Deserializes the key information from an XML string by using the specified format.

System_CAPS_pubmethodGenerateKey(ECCurve)

Generates a key to use for the ECDsaCng algorithm.(Overrides ECDsa.GenerateKey(ECCurve).)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodImportParameters(ECParameters)

Replaces the existing key that the current instance is working with by creating a new CngKey for the parameters structure.(Overrides ECDsa.ImportParameters(ECParameters).)

System_CAPS_pubmethodSignData(Byte())

Generates a signature for the specified data.

System_CAPS_pubmethodSignData(Byte(), HashAlgorithmName)

Computes the hash value of the specified byte array using the specified hash algorithm and signs the resulting hash value. (Inherited from ECDsa.)

System_CAPS_pubmethodSignData(Byte(), Int32, Int32)

Generates a digital signature for the specified length of data, beginning at the specified offset.

System_CAPS_pubmethodSignData(Byte(), Int32, Int32, HashAlgorithmName)

Computes the hash value of a portion of the specified byte array using the specified hash algorithm and signs the resulting hash value. (Inherited from ECDsa.)

System_CAPS_pubmethodSignData(Stream)

Generates a signature for the specified data stream, reading to the end of the stream.

System_CAPS_pubmethodSignData(Stream, HashAlgorithmName)

Computes the hash value of the specified stream using the specified hash algorithm and signs the resulting hash value.(Inherited from ECDsa.)

System_CAPS_pubmethodSignHash(Byte())

Generates a signature for the specified hash value.(Overrides ECDsa.SignHash(Byte()).)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

System_CAPS_pubmethodToXmlString(Boolean)

This method is not implemented.(Overrides AsymmetricAlgorithm.ToXmlString(Boolean).)

System_CAPS_pubmethodToXmlString(ECKeyXmlFormat)

Serializes the key information to an XML string by using the specified format.

System_CAPS_pubmethodVerifyData(Byte(), Byte())

Verifies the digital signature of the specified data.

System_CAPS_pubmethodVerifyData(Byte(), Byte(), HashAlgorithmName)

Verifies that a digital signature is valid by calculating the hash value of the specified data using the specified hash algorithm and comparing it to the provided signature. (Inherited from ECDsa.)

System_CAPS_pubmethodVerifyData(Byte(), Int32, Int32, Byte())

Verifies a signature for the specified length of data, beginning at the specified offset.

System_CAPS_pubmethodVerifyData(Byte(), Int32, Int32, Byte(), HashAlgorithmName)

Verifies that a digital signature is valid by calculating the hash value of the data in a portion of a byte array using the specified hash algorithm and comparing it to the provided signature. (Inherited from ECDsa.)

System_CAPS_pubmethodVerifyData(Stream, Byte())

Verifies the digital signature of the specified data stream, reading to the end of the stream.

System_CAPS_pubmethodVerifyData(Stream, Byte(), HashAlgorithmName)

Verifies that a digital signature is valid by calculating the hash value of the specified stream using the specified hash algorithm and comparing it to the provided signature. (Inherited from ECDsa.)

System_CAPS_pubmethodVerifyHash(Byte(), Byte())

Verifies the specified digital signature against a specified hash value.(Overrides ECDsa.VerifyHash(Byte(), Byte()).)

This class derives from the ECDsa abstract base class.

The following example shows how to use the ECDsaCng class to sign a message and how to use the signature to verify that the message has not been altered.

Imports System
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text

Class Alice

    Public Shared Sub Main(ByVal args() As String)
        Dim bob As New Bob()
        If (True) Then
            Using dsa As New ECDsaCng()
                    dsa.HashAlgorithm = CngAlgorithm.Sha256
                    bob.key = dsa.Key.Export(CngKeyBlobFormat.EccPublicBlob)
                    Dim data() As Byte = {21, 5, 8, 12, 207}
                    Dim signature As Byte() = dsa.SignData(data)
                    bob.Receive(data, signature)
            End Using
        End If

    End Sub 'Main
End Class 'Alice 


Public Class Bob
    Public key() As Byte

    Public Sub Receive(ByVal data() As Byte, ByVal signature() As Byte)
        Using ecsdKey As New ECDsaCng(CngKey.Import(key, CngKeyBlobFormat.EccPublicBlob))
                If ecsdKey.VerifyData(data, signature) Then
                    Console.WriteLine("Data is good")
                Else
                    Console.WriteLine("Data is bad")
                End If
        End Using

    End Sub 'Receive
End Class 'Bob 

.NET Framework
Available since 3.5

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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