ArvoreSecurityUtil - Decryptor para Árvore

ArvoreSecurityUtil.java

package com.ubook.reader.util;

import android.util.Base64;
import android.util.Log;

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

public class ArvoreSecurityUtil {

    private final String TAG = ArvoreSecurityUtil.this.getClass().getSimpleName();

    Cipher ecipher;
    Cipher dcipher;

    public ArvoreSecurityUtil() {
        try {
            byte[] key = getKey();
            byte[] iv = getIV();

            SecretKeySpec skeySpec = new SecretKeySpec(key, "AES");
            IvParameterSpec ivSpec = new IvParameterSpec(iv);

            ecipher = Cipher.getInstance("AES/CBC/NoPadding");
            ecipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivSpec);

            dcipher = Cipher.getInstance("AES/CBC/NoPadding");
            dcipher.init(Cipher.DECRYPT_MODE, skeySpec, ivSpec);
        } catch (Exception e) {
            Log.e(TAG, "", e);
            e.printStackTrace();
        }
    }

    public String encrypt(String str) {
        try {
            // Encode the string into bytes using utf-8
            byte[] utf8 = str.getBytes("UTF8");

            // Encrypt
            byte[] enc = ecipher.doFinal(utf8);

            // Encode bytes to base64 to get a string
            return Base64.encodeToString(enc, Base64.DEFAULT);
        } catch (Exception e) {
            Log.e(TAG, "", e);
            e.printStackTrace();
            return null;
        }
    }

    public String decrypt(String str) {
        try {
            // Decode base64 to get bytes
            byte[] dec = Base64.decode(str, Base64.DEFAULT);

            // Decrypt
            byte[] utf8 = dcipher.doFinal(dec);

            // Decode using utf-8
            return new String(utf8, "UTF8");
        } catch (Exception e) {
            Log.e(TAG, "", e);
            e.printStackTrace();
            return null;
        }
    }

    private byte[] getIV() {
        return base64ToBinary("N9mT3Z5DzqghlBVBC0YsTg==\n");
    }

    private byte[] getKey() {
        return base64ToBinary("6LMmbmbL4EKvi55WJFxZHW5FOH25/RGbuD3Vx8MEYGU=\n");
    }

    private byte[] base64ToBinary(String base64_arg) {
        return Base64.decode(base64_arg, Base64.DEFAULT);
    }

}