This code implements a keylogger for the Windows platform using the WinAPI. The keylogger listens for key presses at a low level and logs them to a file, optionally hiding its console window and checking if the system has completed booting.

Here are some key aspects of the code:

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Features:

1. Key Press Logging:

   • Logs key presses in different formats based on the FORMAT definition (plain text, decimal, hexadecimal).
   • Uses a std::map to provide user-friendly labels for special keys (e.g., [SHIFT], [BACKSPACE]).
   • Detects active window changes and logs the window title along with timestamps.

2. Stealth Mode:

   • The console window visibility is controlled by visible or invisible definitions.
   • Hides the console window completely if invisible is defined.

3. Boot Time Wait:

   • If bootwait is defined, the program waits until the system has finished booting before starting.

4. Mouse Click Ignore:

   • Ignores mouse click events if mouseignore is defined.

5. Keyboard Layout Handling:

   • Adapts to different keyboard layouts using GetKeyboardLayout and MapVirtualKeyExA.

6. Output:

   • Logs keystrokes to a file (keylogger.log).
   • Keeps the file open during runtime for efficiency.

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Security and Ethical Considerations:

• This code can be misused for unethical purposes, such as spying on users without their consent. Ensure it is used in a lawful and ethical manner, such as for personal testing or authorized security audits.
• Unauthorized use of keyloggers may violate privacy laws and regulations.

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Potential Issues and Suggestions:

1. Antivirus Detection:

   • Many antiviruses will flag this code as malicious. To reduce detection:
     • Encrypt or obfuscate the output.
     • Implement runtime encryption/decryption of key presses.

2. File Handling:

   • Ensure the output file is closed properly in case of program termination to avoid data loss.

3. Hook Lifetime:

   • The hook is removed only when the program exits. Consider adding a way to clean up the hook in case of exceptions or unexpected termination.

4. Thread Safety:

   • Access to shared resources (like the output_file) should be thread-safe.

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How to Compile:

Use a Windows compiler like MinGW or MSVC:

g++ keylogger.cpp -o keylogger.exe -luser32 -lgdi32

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