KeyedHashAlgorithm KeyedHashAlgorithm KeyedHashAlgorithm KeyedHashAlgorithm Class

Definition

Stellt die abstrakte Klasse dar, von der alle Implementierungen schlüsselgebundener Hashalgorithmen abgeleitet werden müssen.Represents the abstract class from which all implementations of keyed hash algorithms must derive.

public ref class KeyedHashAlgorithm abstract : System::Security::Cryptography::HashAlgorithm
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class KeyedHashAlgorithm : System.Security.Cryptography.HashAlgorithm
type KeyedHashAlgorithm = class
    inherit HashAlgorithm
Public MustInherit Class KeyedHashAlgorithm
Inherits HashAlgorithm
Vererbung
KeyedHashAlgorithmKeyedHashAlgorithmKeyedHashAlgorithmKeyedHashAlgorithm
Abgeleitet
Attribute

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie für die Ableitung der KeyedHashAlgorithm Klasse.The following code example demonstrates how to derive from the KeyedHashAlgorithm class.

using System;
using System.Security.Cryptography;

public class TestHMACMD5
{
    static private void PrintByteArray(Byte[] arr)
    {
        int i;
        Console.WriteLine("Length: " + arr.Length);
        for (i = 0; i < arr.Length; i++)
        {
            Console.Write("{0:X}", arr[i]);
            Console.Write("    ");
            if ((i + 9) % 8 == 0) Console.WriteLine();
        }
        if (i % 8 != 0) Console.WriteLine();
    }
    public static void Main()
    {
        // Create a key.
        byte[] key1 = { 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b };
        // Pass the key to the constructor of the HMACMD5 class.  
        HMACMD5 hmac1 = new HMACMD5(key1);

        // Create another key.
        byte[] key2 = System.Text.Encoding.ASCII.GetBytes("KeyString");
        // Pass the key to the constructor of the HMACMD5 class.  
        HMACMD5 hmac2 = new HMACMD5(key2);

        // Encode a string into a byte array, create a hash of the array,
        // and print the hash to the screen.
        byte[] data1 = System.Text.Encoding.ASCII.GetBytes("Hi There");
        PrintByteArray(hmac1.ComputeHash(data1));

        // Encode a string into a byte array, create a hash of the array,
        // and print the hash to the screen.
        byte[] data2 = System.Text.Encoding.ASCII.GetBytes("This data will be hashed.");
        PrintByteArray(hmac2.ComputeHash(data2));
    }
}
public class HMACMD5 : KeyedHashAlgorithm
{
    private MD5 hash1;
    private MD5 hash2;
    private bool bHashing = false;

    private byte[] rgbInner = new byte[64];
    private byte[] rgbOuter = new byte[64];

    public HMACMD5(byte[] rgbKey)
    {
        HashSizeValue = 128;
        // Create the hash algorithms.
        hash1 = MD5.Create();
        hash2 = MD5.Create();
        // Get the key.
        if (rgbKey.Length > 64)
        {
            KeyValue = hash1.ComputeHash(rgbKey);
            // No need to call Initialize; ComputeHash does it automatically.
        }
        else
        {
            KeyValue = (byte[])rgbKey.Clone();
        }
        // Compute rgbInner and rgbOuter.
        int i = 0;
        for (i = 0; i < 64; i++)
        {
            rgbInner[i] = 0x36;
            rgbOuter[i] = 0x5C;
        }
        for (i = 0; i < KeyValue.Length; i++)
        {
            rgbInner[i] ^= KeyValue[i];
            rgbOuter[i] ^= KeyValue[i];
        }
    }

    public override byte[] Key
    {
        get { return (byte[])KeyValue.Clone(); }
        set
        {
            if (bHashing)
            {
                throw new Exception("Cannot change key during hash operation");
            }
            if (value.Length > 64)
            {
                KeyValue = hash1.ComputeHash(value);
                // No need to call Initialize; ComputeHash does it automatically.
            }
            else
            {
                KeyValue = (byte[])value.Clone();
            }
            // Compute rgbInner and rgbOuter.
            int i = 0;
            for (i = 0; i < 64; i++)
            {
                rgbInner[i] = 0x36;
                rgbOuter[i] = 0x5C;
            }
            for (i = 0; i < KeyValue.Length; i++)
            {
                rgbInner[i] ^= KeyValue[i];
                rgbOuter[i] ^= KeyValue[i];
            }
        }
    }
    public override void Initialize()
    {
        hash1.Initialize();
        hash2.Initialize();
        bHashing = false;
    }
    protected override void HashCore(byte[] rgb, int ib, int cb)
    {
        if (bHashing == false)
        {
            hash1.TransformBlock(rgbInner, 0, 64, rgbInner, 0);
            bHashing = true;
        }
        hash1.TransformBlock(rgb, ib, cb, rgb, ib);
    }

    protected override byte[] HashFinal()
    {
        if (bHashing == false)
        {
            hash1.TransformBlock(rgbInner, 0, 64, rgbInner, 0);
            bHashing = true;
        }
        // Finalize the original hash.
        hash1.TransformFinalBlock(new byte[0], 0, 0);
        // Write the outer array.
        hash2.TransformBlock(rgbOuter, 0, 64, rgbOuter, 0);
        // Write the inner hash and finalize the hash.
        hash2.TransformFinalBlock(hash1.Hash, 0, hash1.Hash.Length);
        bHashing = false;
        return hash2.Hash;
    }
}
Imports System
Imports System.Security.Cryptography
 _

Public Class TestHMACMD5

    Private Shared Sub PrintByteArray(ByVal arr() As [Byte])
        Dim i As Integer
        Console.WriteLine(("Length: " + arr.Length.ToString()))
        For i = 0 To arr.Length - 1
            Console.Write("{0:X}", arr(i))
            Console.Write("    ")
            If (i + 9) Mod 8 = 0 Then
                Console.WriteLine()
            End If
        Next i
        If i Mod 8 <> 0 Then
            Console.WriteLine()
        End If
    End Sub

    Public Shared Sub Main()
        ' Create a key.
        Dim key1 As Byte() = {&HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB, &HB}
        ' Pass the key to the constructor of the HMACMD5 class.  
        Dim hmac1 As New HMACMD5(key1)

        ' Create another key.
        Dim key2 As Byte() = System.Text.Encoding.ASCII.GetBytes("KeyString")
        ' Pass the key to the constructor of the HMACMD5 class.  
        Dim hmac2 As New HMACMD5(key2)

        ' Encode a string into a byte array, create a hash of the array,
        ' and print the hash to the screen.
        Dim data1 As Byte() = System.Text.Encoding.ASCII.GetBytes("Hi There")
        PrintByteArray(hmac1.ComputeHash(data1))

        ' Encode a string into a byte array, create a hash of the array,
        ' and print the hash to the screen.
        Dim data2 As Byte() = System.Text.Encoding.ASCII.GetBytes("This data will be hashed.")
        PrintByteArray(hmac2.ComputeHash(data2))
    End Sub
End Class
 _

Public Class HMACMD5
    Inherits KeyedHashAlgorithm
    Private hash1 As MD5
    Private hash2 As MD5
    Private bHashing As Boolean = False

    Private rgbInner(64) As Byte
    Private rgbOuter(64) As Byte


    Public Sub New(ByVal rgbKey() As Byte)
        HashSizeValue = 128
        ' Create the hash algorithms.
        hash1 = MD5.Create()
        hash2 = MD5.Create()
        ' Get the key.
        If rgbKey.Length > 64 Then
            KeyValue = hash1.ComputeHash(rgbKey)
            ' No need to call Initialize; ComputeHash does it automatically.
        Else
            KeyValue = CType(rgbKey.Clone(), Byte())
        End If
        ' Compute rgbInner and rgbOuter.
        Dim i As Integer = 0
        For i = 0 To 63
            rgbInner(i) = &H36
            rgbOuter(i) = &H5C
        Next i
        i = 0
        For i = 0 To KeyValue.Length - 1
            rgbInner(i) = rgbInner(i) Xor KeyValue(i)
            rgbOuter(i) = rgbOuter(i) Xor KeyValue(i)
        Next i
    End Sub


    Public Overrides Property Key() As Byte()
        Get
            Return CType(KeyValue.Clone(), Byte())
        End Get
        Set(ByVal Value As Byte())
            If bHashing Then
                Throw New Exception("Cannot change key during hash operation")
            End If
            If value.Length > 64 Then
                KeyValue = hash1.ComputeHash(value)
                ' No need to call Initialize; ComputeHash does it automatically.
            Else
                KeyValue = CType(value.Clone(), Byte())
            End If
            ' Compute rgbInner and rgbOuter.
            Dim i As Integer = 0
            For i = 0 To 63
                rgbInner(i) = &H36
                rgbOuter(i) = &H5C
            Next i
            For i = 0 To KeyValue.Length - 1
                rgbInner(i) ^= KeyValue(i)
                rgbOuter(i) ^= KeyValue(i)
            Next i
        End Set
    End Property


    Public Overrides Sub Initialize()
        hash1.Initialize()
        hash2.Initialize()
        bHashing = False
    End Sub


    Protected Overrides Sub HashCore(ByVal rgb() As Byte, ByVal ib As Integer, ByVal cb As Integer)
        If bHashing = False Then
            hash1.TransformBlock(rgbInner, 0, 64, rgbInner, 0)
            bHashing = True
        End If
        hash1.TransformBlock(rgb, ib, cb, rgb, ib)
    End Sub


    Protected Overrides Function HashFinal() As Byte()
        If bHashing = False Then
            hash1.TransformBlock(rgbInner, 0, 64, rgbInner, 0)
            bHashing = True
        End If
        ' Finalize the original hash.
        hash1.TransformFinalBlock(New Byte(0) {}, 0, 0)
        ' Write the outer array.
        hash2.TransformBlock(rgbOuter, 0, 64, rgbOuter, 0)
        ' Write the inner hash and finalize the hash.
        hash2.TransformFinalBlock(hash1.Hash, 0, hash1.Hash.Length)
        bHashing = False
        Return hash2.Hash
    End Function
End Class

Hinweise

Hash ordnen binäre Zeichenfolgen eine beliebige Länge kleinen binären Zeichenfolgen fester Länge.Hash functions map binary strings of an arbitrary length to small binary strings of a fixed length. Eine kryptografischen Hashfunktion ist die Eigenschaft, dass es rechnerisch unmöglich, zwei verschiedene Eingabewerte zu ermitteln, Hashwert auf den gleichen Wert ist.A cryptographic hash function has the property that it is computationally infeasible to find two distinct inputs that hash to the same value. Kleine Änderungen an den Daten führen große, unvorhersehbare Änderungen im HashSet.Small changes to the data result in large, unpredictable changes in the hash.

Ein schlüsselgebundenen Hashalgorithmus ist eine abhängige Schlüssel, unidirektionale Hashfunktion, die als einen Nachrichtenauthentifizierungscode verwendet.A keyed hash algorithm is a key-dependent, one-way hash function used as a message authentication code. Nur ein Benutzer, die die Schlüssel bekannt ist, kann der Hashwert überprüft werden.Only someone who knows the key can verify the hash. Verschlüsselte Hashalgorithmen bieten Authentifizierung, jedoch keine Secrecy.Keyed hash algorithms provide authenticity without secrecy.

Hashfunktionen werden häufig bei digitalen Signaturen und für die Datenintegrität verwendet.Hash functions are commonly used with digital signatures and for data integrity. Die HMACSHA1 Klasse ist ein Beispiel eines schlüsselgebundenen Hashalgorithmus.The HMACSHA1 class is an example of a keyed hash algorithm.

Konstruktoren

KeyedHashAlgorithm() KeyedHashAlgorithm() KeyedHashAlgorithm() KeyedHashAlgorithm()

Initialisiert eine neue Instanz der KeyedHashAlgorithm-Klasse.Initializes a new instance of the KeyedHashAlgorithm class.

Felder

HashSizeValue HashSizeValue HashSizeValue HashSizeValue

Stellt die Größe des berechneten Hashcodes in Bits dar.Represents the size, in bits, of the computed hash code.

(Inherited from HashAlgorithm)
HashValue HashValue HashValue HashValue

Stellt den Wert des errechneten Hashcodes dar.Represents the value of the computed hash code.

(Inherited from HashAlgorithm)
KeyValue KeyValue KeyValue KeyValue

Der im Hashalgorithmus zu verwendende Schlüssel.The key to use in the hash algorithm.

State State State State

Stellt den Zustand der Hashberechnung dar.Represents the state of the hash computation.

(Inherited from HashAlgorithm)

Eigenschaften

CanReuseTransform CanReuseTransform CanReuseTransform CanReuseTransform

Ruft einen Wert ab, der angibt, ob die aktuelle Transformation wiederverwendet werden kann.Gets a value indicating whether the current transform can be reused.

(Inherited from HashAlgorithm)
CanTransformMultipleBlocks CanTransformMultipleBlocks CanTransformMultipleBlocks CanTransformMultipleBlocks

Ruft beim Überschreiben in einer abgeleiteten Klasse einen Wert ab, der angibt, ob mehrere Blöcke transformiert werden können.When overridden in a derived class, gets a value indicating whether multiple blocks can be transformed.

(Inherited from HashAlgorithm)
Hash Hash Hash Hash

Ruft den Wert des berechneten Hashcodes ab.Gets the value of the computed hash code.

(Inherited from HashAlgorithm)
HashSize HashSize HashSize HashSize

Ruft die Größe des berechneten Hashcodes in Bits ab.Gets the size, in bits, of the computed hash code.

(Inherited from HashAlgorithm)
InputBlockSize InputBlockSize InputBlockSize InputBlockSize

Ruft beim Überschreiben in einer abgeleiteten Klasse die Eingabeblockgröße ab.When overridden in a derived class, gets the input block size.

(Inherited from HashAlgorithm)
Key Key Key Key

Ruft den im Hashalgorithmus zu verwendenden Schlüssel ab oder legt diesen fest.Gets or sets the key to use in the hash algorithm.

OutputBlockSize OutputBlockSize OutputBlockSize OutputBlockSize

Ruft beim Überschreiben in einer abgeleiteten Klasse die Ausgabeblockgröße ab.When overridden in a derived class, gets the output block size.

(Inherited from HashAlgorithm)

Methoden

Clear() Clear() Clear() Clear()

Gibt alle von der HashAlgorithm-Klasse verwendeten Ressourcen frei.Releases all resources used by the HashAlgorithm class.

(Inherited from HashAlgorithm)
ComputeHash(Byte[]) ComputeHash(Byte[]) ComputeHash(Byte[]) ComputeHash(Byte[])

Errechnet den Hashwert für das angegebene Bytearray.Computes the hash value for the specified byte array.

(Inherited from HashAlgorithm)
ComputeHash(Byte[], Int32, Int32) ComputeHash(Byte[], Int32, Int32) ComputeHash(Byte[], Int32, Int32) ComputeHash(Byte[], Int32, Int32)

Berechnet den Hashwert für den angegebenen Bereich des angegebenen Bytearrays.Computes the hash value for the specified region of the specified byte array.

(Inherited from HashAlgorithm)
ComputeHash(Stream) ComputeHash(Stream) ComputeHash(Stream) ComputeHash(Stream)

Berechnet den Hashwert für das angegebene Stream-Objekt.Computes the hash value for the specified Stream object.

(Inherited from HashAlgorithm)
Create() Create() Create() Create()

Erstellt eine Instanz der Standardimplementierung eines schlüsselgebundenen Hashalgorithmus.Creates an instance of the default implementation of a keyed hash algorithm.

Create(String) Create(String) Create(String) Create(String)

Erstellt eine Instanz der angegebenen Implementierung eines schlüsselgebundenen Hashalgorithmus.Creates an instance of the specified implementation of a keyed hash algorithm.

Dispose() Dispose() Dispose() Dispose()

Gibt alle von der aktuellen Instanz der HashAlgorithm-Klasse verwendeten Ressourcen frei.Releases all resources used by the current instance of the HashAlgorithm class.

(Inherited from HashAlgorithm)
Dispose(Boolean) Dispose(Boolean) Dispose(Boolean) Dispose(Boolean)

Gibt die von KeyedHashAlgorithm verwendeten nicht verwalteten Ressourcen und optional die verwalteten Ressourcen frei.Releases the unmanaged resources used by the KeyedHashAlgorithm and optionally releases the managed resources.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Bestimmt, ob das angegebene Objekt mit dem aktuellen Objekt identisch ist.Determines whether the specified object is equal to the current object.

(Inherited from Object)
Finalize() Finalize() Finalize() Finalize()

Dieser Member überschreibt Finalize(). Das zugehörige Thema enthält möglicherweise eine umfassendere Dokumentation.This member overrides Finalize(), and more complete documentation might be available in that topic.

Gibt einem Object Gelegenheit zu dem Versuch, Ressourcen freizugeben und andere Bereinigungen durchzuführen, bevor das Object von der Garbage Collection freigegeben wird.Allows an Object to attempt to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Fungiert als Standardhashfunktion.Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Ruft den Type der aktuellen Instanz ab.Gets the Type of the current instance.

(Inherited from Object)
HashCore(Byte[], Int32, Int32) HashCore(Byte[], Int32, Int32) HashCore(Byte[], Int32, Int32) HashCore(Byte[], Int32, Int32)

Leitet beim Überschreiben in einer abgeleiteten Klasse die in das Objekt geschriebenen Daten zum Errechnen des Hashs an den Hashalgorithmus weiter.When overridden in a derived class, routes data written to the object into the hash algorithm for computing the hash.

(Inherited from HashAlgorithm)
HashCore(ReadOnlySpan<Byte>) HashCore(ReadOnlySpan<Byte>) HashCore(ReadOnlySpan<Byte>) HashCore(ReadOnlySpan<Byte>) Inherited from HashAlgorithm
HashFinal() HashFinal() HashFinal() HashFinal()

Schließt beim Überschreiben in einer abgeleiteten Klasse die Berechnung des Hashs ab, nachdem die letzten Daten vom Kryptografiestreamobjekt verarbeitet wurden.When overridden in a derived class, finalizes the hash computation after the last data is processed by the cryptographic stream object.

(Inherited from HashAlgorithm)
Initialize() Initialize() Initialize() Initialize()

Initialisiert eine Implementierung der HashAlgorithm-Klasse.Initializes an implementation of the HashAlgorithm class.

(Inherited from HashAlgorithm)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Erstellt eine flache Kopie des aktuellen Object.Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Gibt eine Zeichenfolge zurück, die das aktuelle Objekt darstellt.Returns a string that represents the current object.

(Inherited from Object)
TransformBlock(Byte[], Int32, Int32, Byte[], Int32) TransformBlock(Byte[], Int32, Int32, Byte[], Int32) TransformBlock(Byte[], Int32, Int32, Byte[], Int32) TransformBlock(Byte[], Int32, Int32, Byte[], Int32)

Errechnet den Hashwert für den angegebenen Bereich des Eingabebytearrays und kopiert den angegebenen Bereich des Eingabebytearrays in den angegebenen Bereich des Ausgabebytearrays.Computes the hash value for the specified region of the input byte array and copies the specified region of the input byte array to the specified region of the output byte array.

(Inherited from HashAlgorithm)
TransformFinalBlock(Byte[], Int32, Int32) TransformFinalBlock(Byte[], Int32, Int32) TransformFinalBlock(Byte[], Int32, Int32) TransformFinalBlock(Byte[], Int32, Int32)

Berechnet den Hashwert für den angegebenen Bereich des angegebenen Bytearrays.Computes the hash value for the specified region of the specified byte array.

(Inherited from HashAlgorithm)
TryComputeHash(ReadOnlySpan<Byte>, Span<Byte>, Int32) TryComputeHash(ReadOnlySpan<Byte>, Span<Byte>, Int32) TryComputeHash(ReadOnlySpan<Byte>, Span<Byte>, Int32) TryComputeHash(ReadOnlySpan<Byte>, Span<Byte>, Int32) Inherited from HashAlgorithm
TryHashFinal(Span<Byte>, Int32) TryHashFinal(Span<Byte>, Int32) TryHashFinal(Span<Byte>, Int32) TryHashFinal(Span<Byte>, Int32) Inherited from HashAlgorithm

Explizite Schnittstellenimplementierungen

IDisposable.Dispose() IDisposable.Dispose() IDisposable.Dispose() IDisposable.Dispose()

Gibt die von HashAlgorithm verwendeten nicht verwalteten Ressourcen und optional die verwalteten Ressourcen frei.Releases the unmanaged resources used by the HashAlgorithm and optionally releases the managed resources.

(Inherited from HashAlgorithm)

Gilt für:

Siehe auch