2FA CLI

A simple command-line utility that allows users to securely add 2FA secrets and get OTP codes for various accounts directly from the terminal.

All secret keys are encrypted using a key derived from a password, which is set when adding first entry. The password itself is securely hashed using bcrypt.

Entries are stored in the $HOME directory on Linux and the %USERPROFILE% directory on Windows in a .2fa-cli.json file.

Usage

$ 2fa -h
Description:
  2FA CLI tool

Usage:
  2fa [command] [options]

Options:
  --version       Show version information
  -?, -h, --help  Show help and usage information

Commands:
  add <service> <secret-key>  Adds a new entry
  get <service>               Gets the current OTP code for a specified entry
  list                        Lists all entries
  remove, rm <service>        Removes an existing entry

Examples

Adding a new entry:

$ 2fa add github nbswy3dpor3w6ztb
Entry 'github' added.

Getting the current OTP code for a specified entry:

$ 2fa get github
924313

Listing all entries:

$ 2fa list
github

Removing an existing entry:

$ 2fa rm github
Entry 'github' removed.

Password

Each time the add or get commands are used, the tool prompts for a password to encrypt or decrypt secret keys.

$ 2fa get github
Enter password:

For convenience, the password can also be provided using the _2FA_CLI_PASSWORD environment variable.

# Linux example
export _2FA_CLI_PASSWORD='s0M35tr0NgP4$$W0rD'

^{Warning: Storing passwords in environment variables can pose a security risk as they may be accessible by other processes running on the same system. Use this method only in secure environments and avoid using it on shared or multi-user systems. Ensure that the environment variable is cleared or removed after use to minimize exposure.}

.2fa-cli.json example

{
  "PasswordHash": "$2a$11$gVUQlYe2WldoCo93JxdLe.tQgN.eD1QYcbxB69skesa4QYZjEmEJK",
  "Entries": [
    {
      "Service": "github",
      "SecretKey": "DmVSS8L27lGQ7cWsrWzEzg==:2KXQIEWTbrONknsO2wWxUMXLx6MMY41sx2FAkiIJhR8=",
      "Type": "totp",
      "Digits": 6
    }
  ]
}

Download

Build from source

1. Make sure you have installed Git and .NET SDK

2. Clone the repository

   git clone https://github.com/jurakovic/2fa-cli.git
   cd 2fa-cli

3. Build (publish) with dotnet

   cd src
   dotnet publish -c Release --self-contained
   bin/Release/net8.0/linux-x64/publish/2fa -h
   # mv to desired path

Technologies

Title	GitHub	NuGet
System.CommandLine	dotnet/command-line-api	System.CommandLine
bcrypt.net	BcryptNet/bcrypt.net	BCrypt.Net-Next
Otp.NET	kspearrin/Otp.NET	Otp.NET
TextCopy	CopyText/TextCopy	TextCopy

Disclaimer

This tool is intended for educational and personal use only. While every effort has been made to ensure the security and integrity of stored 2FA secrets, it is not recommended for use in high-security environments or as a replacement for professional-grade security solutions. Use this tool at your own risk. The author is not responsible for any data loss, security breaches, or other issues that may arise from the use of this software.