steGo

A powerful command-line tool for hiding messages in images using steganography. steGo supports encoding and decoding messages in PNG images using the LSB (Least Significant Bit) method.

Features

• Message Encoding: Hide messages in PNG images
• Message Decoding: Extract hidden messages from images
• File Support: Encode/Decode text files
• Configuration: Customizable through config files and environment variables
• Shell Integration: Shell completion for bash, zsh, fish, and PowerShell
• Cross-Platform: Works on Linux, macOS, and Windows

Installation

From Source

1. Clone the repository:

   git clone https://github.com/thvl3/steGo.git
   cd steGo

2. Build the project:

   go build -o steGo ./cmd/steGo

3. Install the binary:

   # Linux/macOS
   sudo install steGo /usr/local/bin
   
   # Windows (PowerShell)
   # Create a directory for your executables if you don't have one, e.g., $HOME\bin
   # mkdir $HOME\bin -ErrorAction SilentlyContinue
   # Copy steGo.exe to that directory:
   Copy-Item .\steGo.exe -Destination "$HOME\bin\steGo.exe"
   # Ensure that the directory (e.g., $HOME\bin) is in your PATH.
   # You can check by running: $env:Path -split ';'
   # To add it temporarily for the current session: $env:Path += ";$HOME\bin"
   # For a permanent change, search for "Edit the system environment variables" in Windows.

Windows Execution Notes

Sometimes, antivirus software on Windows might incorrectly flag steGo.exe as malicious. If you encounter this, or face permission issues when trying to run the program, consider the following:

• Antivirus Exception: Add an exception for steGo.exe in your antivirus software. The steps for this vary depending on your antivirus program.
• Run as Administrator (Use with Caution): You can try running PowerShell as an administrator. Right-click on the PowerShell icon and select "Run as administrator". However, be cautious when running any program with elevated privileges.
• Verify the Source: Ensure you have downloaded steGo from the official GitHub releases page to minimize risks.

From Release

Download the latest release from the releases page and install the appropriate binary for your platform:

Platform	Binary Name
Linux	steGo-linux-amd64
macOS	steGo-darwin-amd64
Windows	steGo-windows-amd64.exe

After downloading, rename the binary to steGo (or steGo.exe on Windows) and install it in your PATH.

Usage

Basic Usage

# Encode a message into an image
steGo encode -i input.png -o output.png -m "Secret message"

# Encode a message from a file
steGo encode -i input.png -o output.png -f message.txt

# Decode a message from an image
steGo decode -i output.png

# Decode a message to a file
steGo decode -i output.png -o message.txt

Shell Completion

# Bash
source <(steGo completion bash)

# Zsh
steGo completion zsh > "${fpath[1]}/_steGo"

# Fish
steGo completion fish | source

# PowerShell
steGo completion powershell | Out-String | Invoke-Expression

Configuration

steGo can be configured using a YAML configuration file. By default, it looks for steGo.yaml in:

• Linux/macOS: $HOME/.config/steGo.yaml
• Windows: %APPDATA%\steGo\steGo.yaml

Example configuration:

verbose: true
default:
  input: "input.png"
  output: "output.png"

You can also use environment variables:

export STEGO_VERBOSE=true
export STEGO_DEFAULT_INPUT="input.png"
export STEGO_DEFAULT_OUTPUT="output.png"

Command Reference

Global Flags

• --config string: config file (default is $HOME/.config/steGo.yaml)
• -v, --verbose: verbose output
• --version: version for steGo

Encode Command

steGo encode [flags]

Flags:

• -f, --file string: file containing message to encode
• -h, --help: help for encode
• -i, --input string: input image file (required)
• -m, --message string: message to encode
• -o, --output string: output image file (required)

Decode Command

steGo decode [flags]

Flags:

• -h, --help: help for decode
• -i, --input string: input image file (required)
• -o, --output string: output file (optional)

Development

Prerequisites

• Go 1.21 or later
• Git

Building

# Build for current platform
go build -o steGo ./cmd/steGo

# Cross-compile for all platforms
GOOS=linux GOARCH=amd64 go build -o steGo-linux-amd64 ./cmd/steGo
GOOS=darwin GOARCH=amd64 go build -o steGo-darwin-amd64 ./cmd/steGo
GOOS=windows GOARCH=amd64 go build -o steGo-windows-amd64.exe ./cmd/steGo

Testing

# Run tests
go test ./...

# Run tests with coverage
go test -cover ./...

Contributing

1. Fork the repository
2. Create a feature branch
3. Commit your changes
4. Push to the branch
5. Create a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Cobra - CLI framework
• Viper - Configuration management