100xuexi_DecryptEpub.java

100xuexi_DecryptEpub.java

import java.io.*;
import java.nio.file.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;

public class dec {

    public static void main(String[] args) throws IOException, NoSuchAlgorithmException, NoSuchPaddingException,
            InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException {
        System.out.println("Initializing...");
        File directory = new File(".");
        directory = new File(directory.getCanonicalPath());
        File[] fs = directory.listFiles();
        for (File f : fs) {
            if (f.getName().endsWith(".html")) {
                System.out.println("Found file to process:" + f.getName());
                Path path = f.toPath();
                byte[] file = Files.readAllBytes(path);
                SecretKeySpec secretKeySpec = new SecretKeySpec("0c5863bcd5f04a80".getBytes("UTF-8"), "AES");
                Cipher instance = Cipher.getInstance("AES/CBC/PKCS5Padding");
                instance.init(2, secretKeySpec, new IvParameterSpec("2f3e6b5cc0154f84".getBytes("UTF-8")));
                String str4;
                try {
                    str4 = new String(instance.doFinal(file), "UTF-8");
                } catch (IllegalBlockSizeException e) {
                    System.out.println("Decrypt fail, skip:" + f.getName());
                    str4="";
                }
                // System.out.println(str4);
                if (str4.indexOf("</") > 1) {
                    System.out.println("Decrypt Success, write back:" + f.getName());
                    BufferedWriter out = new BufferedWriter(new FileWriter(f.getName()));
                    out.write(str4);
                    out.close();
                }

            }
        }
    }

}

搜索GetBookAESKey:Ljava/lang/String;
在requestByRSA下面用logcat把Json打印出来就有key和iv了，替换到本java文件内，把本文件放在OEBPS文件夹内运行即可