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SymmetricKeyAlgorithmProvider 클래스

정의

대칭 키 알고리즘의 공급자를 나타냅니다. 자세한 내용은 암호화 키를 참조하세요.

public ref class SymmetricKeyAlgorithmProvider 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 SymmetricKeyAlgorithmProvider 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 SymmetricKeyAlgorithmProvider
Public NotInheritable Class SymmetricKeyAlgorithmProvider
상속
Object Platform::Object IInspectable SymmetricKeyAlgorithmProvider
특성

Windows 요구 사항

디바이스 패밀리
Windows 10 (10.0.10240.0에서 도입되었습니다.)
API contract
Windows.Foundation.UniversalApiContract (v1.0에서 도입되었습니다.)

예제

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

namespace SampleSymmetricKeyAlgorithmProvider
{
    sealed partial class SymmKeyAlgProviderApp : Application
    {
        public SymmKeyAlgProviderApp()
        {
            // Initialize the application.
            this.InitializeComponent();

            // Initialize the encryption process.
            String strMsg = "1234567812345678";     // Data to encrypt.
            String strAlgName = SymmetricAlgorithmNames.AesCbc;
            UInt32 keyLength = 32;                  // Length of the key, in bytes
            BinaryStringEncoding encoding;          // Binary encoding value
            IBuffer iv;                             // Initialization vector
            CryptographicKey key;                   // Symmetric key

            // Encrypt a message.
            IBuffer buffEncrypted = this.SampleCipherEncryption(
                strMsg,
                strAlgName,
                keyLength,
                out encoding,
                out iv,
                out key);

            // Decrypt a message.
            this.SampleCipherDecryption(
                strAlgName,
                buffEncrypted,
                iv,
                encoding,
                key);
        }

        public IBuffer SampleCipherEncryption(
            String strMsg,
            String strAlgName,
            UInt32 keyLength,
            out BinaryStringEncoding encoding,
            out IBuffer iv,
            out CryptographicKey key)
        {
            // Initialize the initialization vector.
            iv = null;

            // Initialize the binary encoding value.
            encoding = BinaryStringEncoding.Utf8;

            // Create a buffer that contains the encoded message to be encrypted. 
            IBuffer buffMsg = CryptographicBuffer.ConvertStringToBinary(strMsg, encoding);

            // Open a symmetric algorithm provider for the specified algorithm. 
            SymmetricKeyAlgorithmProvider objAlg = SymmetricKeyAlgorithmProvider.OpenAlgorithm(strAlgName);

            // Demonstrate how to retrieve the name of the algorithm used.
            String strAlgNameUsed = objAlg.AlgorithmName;

            // Determine whether the message length is a multiple of the block length.
            // This is not necessary for PKCS #7 algorithms which automatically pad the
            // message to an appropriate length.
            if (!strAlgName.Contains("PKCS7"))
            {
               if ((buffMsg.Length % objAlg.BlockLength) != 0)
                {
                    throw new Exception("Message buffer length must be multiple of block length.");
                }
            }

            // Create a symmetric key.
            IBuffer keyMaterial = CryptographicBuffer.GenerateRandom(keyLength);
            key = objAlg.CreateSymmetricKey(keyMaterial);

            // CBC algorithms require an initialization vector. Here, a random
            // number is used for the vector.
            if (strAlgName.Contains("CBC"))
            {
                iv = CryptographicBuffer.GenerateRandom(objAlg.BlockLength);
            }

            // Encrypt the data and return.
            IBuffer buffEncrypt = CryptographicEngine.Encrypt(key, buffMsg, iv);
            return buffEncrypt;
        }

        public void SampleCipherDecryption(
            String strAlgName,
            IBuffer buffEncrypt,
            IBuffer iv,
            BinaryStringEncoding encoding,
            CryptographicKey key)
        {
            // Declare a buffer to contain the decrypted data.
            IBuffer buffDecrypted;

            // Open an symmetric algorithm provider for the specified algorithm. 
            SymmetricKeyAlgorithmProvider objAlg = SymmetricKeyAlgorithmProvider.OpenAlgorithm(strAlgName);

            // The input key must be securely shared between the sender of the encrypted message
            // and the recipient. The initialization vector must also be shared but does not
            // need to be shared in a secure manner. If the sender encodes a message string 
            // to a buffer, the binary encoding method must also be shared with the recipient.
            buffDecrypted = CryptographicEngine.Decrypt(key, buffEncrypt, iv);

            // Convert the decrypted buffer to a string (for display). If the sender created the
            // original message buffer from a string, the sender must tell the recipient what 
            // BinaryStringEncoding value was used. Here, BinaryStringEncoding.Utf8 is used to
            // convert the message to a buffer before encryption and to convert the decrypted
            // buffer back to the original plaintext.
            String strDecrypted = CryptographicBuffer.ConvertBinaryToString(encoding, buffDecrypted);
        }
    }
}

설명

정적 OpenAlgorithm 메서드를 호출하고 다음 알고리즘 이름 중 하나를 지정하여 SymmetricKeyAlgorithmProvider 개체를 만듭니다.

  • 패딩 없음:+ DES_CBC

  • DES_ECB

  • 3DES_CBC

  • 3DES_ECB

  • RC2_CBC

  • RC2_ECB

  • AES_CBC

  • AES_ECB

  • PKCS#7 블록 패딩 모드:+ AES_CBC_PKCS7

  • AES_ECB_PKCS7

  • DES_CBC_PKCS7

  • DES_ECB_PKCS7

  • 3DES_CBC_PKCS7

  • 3DES_ECB_PKCS7

  • RC2_CBC_PKCS7

  • RC2_ECB_PKCS7

  • 인증된 모드( EncryptedAndAuthenticatedData 클래스 참조):+ AES_GCM

  • AES_CCM

  • 스트림 암호:+ RC4

속성

AlgorithmName

열린 대칭 알고리즘의 이름을 가져옵니다.

BlockLength

열린 알고리즘에 대한 암호화 블록의 크기(바이트)를 가져옵니다.

메서드

CreateSymmetricKey(IBuffer)

대칭 키를 만듭니다.

OpenAlgorithm(String)

SymmetricKeyAlgorithmProvider 클래스의 instance 만들고 사용할 지정된 알고리즘을 엽니다.

적용 대상

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