aes openssl java_如何用 Java 读取 openssl genrsa -aes256 生成的密钥

可以以下代码来读取 OpenSSL 生成的 AES 256 密钥：

import java.io.BufferedReader;
import java.io.FileReader;
import java.security.Key;
import java.security.KeyFactory;
import java.security.spec.PKCS8EncodedKeySpec;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class ReadOpenSSLPrivateKey {
    public static void main(String[] args) throws Exception {
        // 读取私钥文件
        BufferedReader br = new BufferedReader(new FileReader("private_key.pem"));
        String line;
        StringBuilder sb = new StringBuilder();
        while ((line = br.readLine()) != null) {
            if (line.startsWith("-----BEGIN ") || line.startsWith("-----END ")) {
                continue;
            }
            sb.append(line);
        }
        br.close();

        // 解码 Base64 格式的密钥
        byte[] keyBytes = Base64.getDecoder().decode(sb.toString());

        // 获取密码
        String password = "your_password";

        // 生成 AES 密钥
        byte[] ivBytes = new byte[16];
        byte[] saltBytes = Arrays.copyOfRange(keyBytes, 8, 16);
        byte[] keyBytesWithoutSalt = Arrays.copyOfRange(keyBytes, 16, keyBytes.length);
        IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
        SecretKeySpec keySpec = new SecretKeySpec(getAESKey(password, saltBytes), "AES");

        // 解密私钥
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
        byte[] decryptedBytes = cipher.doFinal(keyBytesWithoutSalt);

        // 转换成 Key 对象
        PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(decryptedBytes);
        KeyFactory kf = KeyFactory.getInstance("RSA");
        Key privateKey = kf.generatePrivate(spec);

        System.out.println(privateKey);
    }

    public static byte[] getAESKey(String password, byte[] saltBytes) throws Exception {
        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec spec = new PBEKeySpec(password.toCharArray(), saltBytes, 65536, 256);
        SecretKey tmp = factory.generateSecret(spec);
        return tmp.getEncoded();
    }
}

其中 `private_key.pem` 是 OpenSSL 生成的密钥文件，`your_password` 是生成密钥时设置的密码。这段代码会读取密钥文件，解码 Base64 格式的密钥，生成 AES 密钥，解密私钥，并将其转换成 Java 的 `Key` 对象。