wktWallet - Encrypt/Decrypt Files on WinCE 5.0

This small program encrypts and decrypts files on Win CE 5.0 using the RC4 stream cipher and a 128-bit key. Here is: The user interface sucks badly, but it's my first Windows app and it works for me. Feel free to improve it. Remember that the code is under a GPL3 license, so please return any useful changes to me. The app should not require any special DLLs, just coredll.dll and commctrl.dll.

Usage

There are 4 menu options:
  1. Set Key: set the encryption key. You can enter up to 24 characters here. Obviously, the longer the key the better, and the key should be hard to guess.
  2. Encrypt File: encrypt a file. You are given a file browser window to choose a file. If you have not already set the key, you will be prompted to do this as well.

    The original file is not altered, but an encrypted file is created in the same folder as the original. The new file's name has the trailing dot turned into an underscore, and the suffix ".enc" appended. Thus, the file readme.txt will be encrypted to readme_txt.enc.

  3. Decrypt File: decrypt a file. You are given a file browser window to choose a file with the suffix ".enc". If you have not already set the key, you will be prompted to do this as well.

    The encrypted file is not altered, but a decrypted file is created in the same folder as the original.

  4. Quit: quit the app.

Warren Toomey wkt@tuhs.org, July 2008.