EncryptedFiles

I have a root folder C:\EncryptedFiles. There could be multiple subfolders. Each subfolder could have up to one file. No way of knowing before hand how many subfolders will be there. I need to iterate over each file, decrypt it and output in a separate folder the decrypted file with a file name matching the naming convention ParentDirectoryOfFile_YYYYMMDD.

Initially I was struggling with looping over to decrypt, but that was answered in this post:

Really struggling with double quotes, double percent signs etc in batch script.

So i have a folder, lets call it C:\EncryptedFiles It can have one or more subfolders, and each subfolder can have one or more encrypted file (with extension gpg).

I need to look at everything inside C:\EncyptedFiles folder and iterate over files in each subfolder, and decrypt those files in same place where encrypted file is there.

So if we have another folder called Subfolder1 with file EncryptedFile1.csv.gpg, its absolute path will be

I'm currently getting an AEADBadTagException when trying to decrypt a file I have encrypted. I have searched pretty much everywhere on stackoverflow and unable to find a solution, and hoping there is just a small mistake I have made or something to do with encoding etc., since GCM is unable to verify the tag that it is generating.

I believe the problem is somewhere in the file I am trying to encrypt/decrypt. The same exact code works on an image, however, when I try to encrypt a PDF, it fails and gives me the above error.

The code below is not using CipherOutputStream/CipherInputStream, but I have tried it with both with no luck.

I understand that it the encryption/decryption methods should not be written like this, especially with the hardcoded IVs, but right now I am just trying to get it to work, then properly securing these methods later.

I am using Android KeyStore to get my secret key. I know this part works since I have lots of other pieces in the app using the Keystore with the same methods. Plus, this methods works with an image.

The error is happening on cipher.doFinal(encryptedBytes). When I use CipherInputStream, it happens on CipherInputStream(EncryptedFileStream, cipher)

Here is the code as well as the error stack, any help is greatly appreciated:

Encryption

I know why my problem is occurring but I do not know how to solve it. I am sending multiple files from sender to receiver by sending the following things:

1. Number of files
2. File Name
3. File Size
4. File data(in bytes)

I am making use of readInt(), readUTF() and readLong() to send the first 3 in my list. For the file data I am making use of a buffer by implementing the following code: