/File_Encryption_Decryption_Tool_in_C

A secure file encryption & decryption tool in C using XOR logic, file handling, and logging.

Primary LanguageC

🔐 File Encryption & Decryption Tool (C)

📝 Project Description

This is a File Encryption and Decryption Tool developed in the C programming language.
The main purpose of this project is to protect important data by converting it into an unreadable format (encryption) and later turning it back to its original form (decryption) using a secret key.

When you encrypt a file, the tool reads its contents, applies a secret key using XOR logic, and creates a new file with scrambled text.
When you decrypt, it reads that encrypted file, applies the same key again, and restores the original readable text.

⚙️ How the Project Works

  1. You start the program in VS Code or any C compiler.
  2. The program shows a menu with options:
    • Encrypt a file
    • Decrypt a file
    • Exit
  3. You choose the option (1 or 2).
  4. Enter the input file name (for example, input.txt).
  5. Enter the output file name (for example, encrypted.txt or decrypted.txt).
  6. Enter any secret key (like abc123).
  7. The program processes the file and shows a success message.

✔️ A file named activity_log.txt is also created automatically — it keeps a record of when and which files were encrypted or decrypted.

🧩 Files Created

  • main.c → The main C source code file.
  • input.txt → Your original file (contains normal text).
  • encrypted.txt → Encrypted file (contains unreadable text).
  • decrypted.txt → Decrypted file (original readable text again).
  • activity_log.txt → Automatically created log file that saves activity details with date and time.
  • README.md → This file, which explains the project.

🧠 Concepts Used

  • File handling (fopen, fread, fwrite, fclose)
  • XOR encryption logic
  • Loops and conditions
  • String handling
  • Time and date logging

🧰 How to Run the Project

  1. Open your project folder File_Encryption_Decryption_Tool in VS Code.
  2. Open the terminal in VS Code (Ctrl + ~).
  3. Compile the code using GCC: 
    gcc main.c -o encrypt_tool