KeyDerivationAlgorithmProvider Kelas

Definisi

Ruang nama:

Windows.Security.Cryptography.Core

Mewakili penyedia algoritma derivasi utama.

public ref class KeyDerivationAlgorithmProvider sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
class KeyDerivationAlgorithmProvider final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
public sealed class KeyDerivationAlgorithmProvider

Public NotInheritable Class KeyDerivationAlgorithmProvider

Warisan

Object Platform::Object IInspectable KeyDerivationAlgorithmProvider

Atribut

ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

Persyaratan Windows

Rangkaian perangkat	Windows 10 (diperkenalkan dalam 10.0.10240.0)
API contract	Windows.Foundation.UniversalApiContract (diperkenalkan dalam v1.0)

Contoh

using Windows.Security.Cryptography;
using Windows.Security.Cryptography.Core;
using Windows.Storage.Streams;

namespace SampleKeyDerivationAlgorithm
{
    sealed partial class SampleKeyDerivationProviderApp : Application
    {
        public SampleKeyDerivationProviderApp()
        {
            // Initialize the Application.
            this.InitializeComponent();

            // Derive key material from a password-based key derivation function.
            String strKdfAlgName = KeyDerivationAlgorithmNames.Pbkdf2Sha256;
            UInt32 targetKeySize = 32;
            UInt32 iterationCount = 10000;
            IBuffer buffKeyMatl = this.SampleDeriveKeyMaterialPbkdf(
                strKdfAlgName,
                targetKeySize,
                iterationCount);

            // Create a key.
            CryptographicKey key = this.SampleCreateKDFKey(
                strKdfAlgName,
                buffKeyMatl);
        }

        public IBuffer SampleDeriveKeyMaterialPbkdf(
            String strAlgName,
            UInt32 targetKeySize,
            UInt32 iterationCount)
        {

            // Open the specified algorithm.
            KeyDerivationAlgorithmProvider objKdfProv = KeyDerivationAlgorithmProvider.OpenAlgorithm(strAlgName);

            // Demonstrate how to retrieve the algorithm name.
            String strAlgUsed = objKdfProv.AlgorithmName;

            // Create a buffer that contains the secret used during derivation.
            String strSecret = "MyPassword";
            IBuffer buffSecret = CryptographicBuffer.ConvertStringToBinary(strSecret, BinaryStringEncoding.Utf8);

            // Create a random salt value.
            IBuffer buffSalt = CryptographicBuffer.GenerateRandom(32);

            // Create the derivation parameters.
            KeyDerivationParameters pbkdf2Params = KeyDerivationParameters.BuildForPbkdf2(buffSalt, iterationCount);

            // Create a key from the secret value.
            CryptographicKey keyOriginal = objKdfProv.CreateKey(buffSecret);

            // Derive a key based on the original key and the derivation parameters.
            IBuffer keyMaterial = CryptographicEngine.DeriveKeyMaterial(
                keyOriginal,
                pbkdf2Params,
                targetKeySize);

            // Demonstrate checking the iteration count.
            UInt32 iterationCountOut = pbkdf2Params.IterationCount;

            // Demonstrate returning the derivation parameters to a buffer.
            IBuffer buffParams = pbkdf2Params.KdfGenericBinary;

            // return the KDF key material.
            return keyMaterial;
        }

        public CryptographicKey SampleCreateKDFKey(
            String strAlgName,
            IBuffer buffKeyMaterial)
        {
            // Create a KeyDerivationAlgorithmProvider object and open the specified algorithm.
            KeyDerivationAlgorithmProvider objKdfAlgProv = KeyDerivationAlgorithmProvider.OpenAlgorithm(strAlgName);

            // Create a key by using the KDF parameters.
            CryptographicKey key = objKdfAlgProv.CreateKey(buffKeyMaterial);

            return key;
        }
    }
}

Keterangan

Ketika dua pihak atau lebih berbagi kunci konten rahasia, seringkali perlu untuk mendapatkan kunci tambahan untuk digunakan dalam operasi kriptografi. Hal ini juga sering diperlukan bagi pihak ketiga tepercaya untuk mendapatkan kunci kriptografi yang berbeda dari satu kunci master. Fungsi derivasi utama digunakan untuk mendapatkan kunci tambahan ini.

Anda dapat menggunakan metode DeriveKeyMaterial statis di kelas CryptographicEngine dan metode berikut di kelas KeyDerivationParameters untuk mendapatkan kunci.

Metode	Deskripsi
BuildForPbkdf2	Membuat objek KeyDerivationParameters untuk digunakan dalam fungsi derivasi kunci berbasis kata sandi 2 (PBKDF2).
BuildForSP800108	Membuat objek KeyDerivationParameters untuk digunakan dalam mode penghitung, fungsi derivasi kunci kode autentikasi pesan berbasis hash (HMAC).
BuildForSP80056a	Membuat objek KeyDerivationParameters untuk digunakan dalam fungsi derivasi kunci SP800-56A.

Anda membuat objek KeyDerivationAlgorithmProvider dengan memanggil metode OpenAlgorithm statis.

Properti

AlgorithmName

Mendapatkan nama algoritma fungsi derivasi kunci terbuka (KDF).

Metode

CreateKey(IBuffer)	Membuat kunci KDF.
OpenAlgorithm(String)	Membuat instans kelas KeyDerivationAlgorithmProvider dan membuka algoritma yang ditentukan untuk digunakan.

Lihat juga

• CryptographicEngine
• KeyDerivationParameters