Question

我使用Flexi Provider（用于McEliece算法）生成我的公钥和私钥，然后我将其保存到文件中，现在我需要从文件加载keypair，我可以读取文件并获取公钥字节数组和私钥字节数组，但我不知道如何从中创建KeyPair：我使用flexiprovider.de作为McEliece算法：

用于生成McEliece键：

import de.flexiprovider.api.keys.KeySpec;
import de.flexiprovider.core.FlexiCoreProvider;
import de.flexiprovider.pqc.FlexiPQCProvider;
import de.flexiprovider.pqc.ecc.mceliece.McElieceKeyFactory;
import de.flexiprovider.pqc.ecc.mceliece.McElieceKeyPairGenerator;

public KeyPair generateKeyPair(){
    KeyPair kp = null;
    int KeySize = 256;
    Security.addProvider(new FlexiCoreProvider());
    Security.addProvider(new FlexiPQCProvider());

    try
    {

        McElieceKeyPairGenerator mcElieceKeyPairGenerator = new McElieceKeyPairGenerator();
        mcElieceKeyPairGenerator.initialize(KeySize, new SecureRandom());
        kp = mcElieceKeyPairGenerator.generateKeyPair();
    } catch (Exception e) {
        System.out.println(e.ToString());
    }
    return kp;
}

从字节数组加载KeyPair：

public KeyPair readKeyPair(byte[] privateKey, byte[] publicKey){
       //?? How can i create KeyPair
}

我尝试使用 McElieceKeyFactory ，但我不知道如何使用它，它需要 KeySpec （de.flexiprovider.api.keys.KeySpec）来生成私钥和公钥但是de.flexiprovider.api.keys.KeySpec是抽象类，我不能从中创建新实例。那我该怎么办？

编辑1： 保存方法：

public void writeFile(byte[] data, String fileName) throws IOException{
    FileOutputStream out = new FileOutputStream(fileName);
    out.write(data);
    out.close();
}

public void saveKeyPair(KeyPair keyPair){
    byte[] privateKeyBytes = keyPair.getPrivate().getEncoded();
    byte[] publicKeyBytes = keyPair.getPublic().getEncoded();

    writeFile(privateKeyBytes,"Private.key");
    writeFile(publicKeyBytes,"Public.key");
}

Answer 1

请尝试以下代码。另请注意，我不直接使用密钥对生成器和密钥工厂实现。

KeyPairGenerator mcElieceKeyPairGenerator = KeyPairGenerator.getInstance("McEliece");
mcElieceKeyPairGenerator.initialize(keysize, new SecureRandom());
kp = mcElieceKeyPairGenerator.generateKeyPair();

final byte[] publicKeyData = kp.getPublic().getEncoded(); 
X509EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKeyData);
KeyFactory mcElieceKeyFactory = KeyFactory.getInstance("McEliece");
PublicKey regeneratedPublicKey = mcElieceKeyFactory.generatePublic(publicKeySpec);

final byte[] privateKeyData = kp.getPrivate().getEncoded();
PKCS8EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(privateKeyData);
PrivateKey regeneratedPrivateKey = mcElieceKeyFactory.generatePrivate(privateKeySpec);

McEliece（FlexiProvider）：如何从字节数组创建KeyPair？

1 个答案: