Dex String Encryption in Sketchware Pro

     StringFog in Sketchware Pro 

StringFog is really useful when it comes to string encryption.

In the vast majority of Android applications, many privacy information exists in the form of strings, such as AppId, AppSecret of third-party platform accessed, and interface address fields, which generally exist in plaintext. If we can encrypt and replace the strings in Dex at packaging time and call decryption at runtime, we can avoid the existence of plaintext in Dex. Although it can not be completely avoided to be cracked, it increases the difficulty of retrieving information, and the security is undoubtedly improved a lot.

StringFold uses Base64 which encodes and decodes data and XOR algorithm which obtains both encrypted and decrypted data.In this way, it not only solves the problem of character encoding, but also solves the problem of encrypting and decrypting (note that Base64 is not strictly an encryption algorithm), and it also gets reliable guarantee in performance.

Below are codes that give example of how StringFold uses the two components ;

public static String encode(String data, String key) {
    return new String(Base64.encode(xor(data.getBytes(), key), Base64.NO_WRAP));
}

public static String decode(String data, String key) {
    return new String(xor(Base64.decode(data, Base64.NO_WRAP), key));
}

When you open Sketchware Pro apk, to the right drawer, you will see a StringFold feature by the Sketchware Pro team.




By just activating it, all your strings will be encrypted on compilation time,


Although your app cannot be completely guaranteed to be cracked, StringFold increases the difficulty for anyone, including reverse engineers, to retrieve information from your app. And thus, security will be improved alot.

The StringFold source code and implementation is in GitHub for more reference,
https://github.com/MegatronKing/StringFog

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Am so glad you could read this post today, i hope it helped you get to know a bit about stringfog in sketchware pro.
If you have any questions regarding this topic, kindly leave a comment on this post.
Thank you and have a nice day.