TexCrypt

TexCrypt is a lightweight, secure, and user-friendly CLI tool built in Go for encrypting and decrypting text-based files using AES-256-GCM. Designed with simplicity in mind, TexCrypt ensures that sensitive file contents can be safely encrypted using strong passwords and modern cryptographic standards while keeping the experience user-friendly.

Whether you're storing personal notes, passwords, or secrets, TexCrypt provides a seamless way to lock down your data with minimal friction.

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Features

• AES-256-GCM Encryption – Provides both confidentiality and integrity.
• Password-Based Encryption – Uses Argon2id to derive secure keys from passwords.
• Salt + Nonce Randomization – Each encryption operation uses unique salt and nonce values.
• Simple CLI Interface – Easy to use with only a couple of flags.
• Secure File Output – Encrypted output stored as .texcrypted.
• Safe Password Entry – Prompts for password without echoing to the terminal.

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Installation

From Prebuilt Releases

1. Visit the Releases page.

2. Download the binary for your platform.

3. Make it executable:

   chmod +x texcrypt

4. Run it:

   ./texcrypt --help

Compiling from Source

Ensure you have Go 1.20+ installed:

git clone https://github.com/dhr412/texcrypt.git
cd texcrypt/src
go build -o texcrypt
./texcrypt --help

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Usage

texcrypt --encrypt <file> | --decrypt <file> [--help]

Flags

• --encrypt <file> – Encrypt a .txt or .md file using a password.
• --decrypt <file> – Decrypt a .texcrypted file using the original password.
• --help – Show usage instructions.

Only .txt and .md files are allowed for encryption for now. Only .texcrypted files are valid for decryption.

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Example

Encrypting a File

texcrypt --encrypt secrets.txt

• Prompts for password and confirmation.
• Outputs: secrets.texcrypted

Decrypting a File

texcrypt --decrypt secrets.texcrypted

• Prompts for the same password used to encrypt.
• Outputs: secrets_decrypted.txt

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How It Works

1. Input Handling:

   • Flags are parsed using Go’s flag package.
   • Validates file types and required options.

2. Encryption:

   • Prompts for password twice (with hidden input).
   • Generates 32-byte random salt and nonce.
   • Derives a 256-bit AES key using Argon2id.
   • Encrypts file content using AES-GCM.
   • Writes [salt][nonce][ciphertext] to a .texcrypted file.

3. Decryption:

   • Prompts for password (once).
   • Extracts salt and nonce from the file.
   • Re-derives the key using Argon2.
   • Decrypts the data and writes plaintext to <original>_decrypted.<extension>.

4. Security Measures:

   • Password input is hidden.
   • AES-GCM provides both encryption and authentication.
   • Key derivation is hardened using salt and Argon2.

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License

This project is open-sourced under the MIT license.