Generate two factor authentication codes that are compatible with Google Authenticator (a.k.a. RFC6238 TOTP) from the shell.

RFC6238

Just download and install ga somewhere on your path (e.g., $HOME/bin/ga).

Requirements:

• gnupg

Optional dependencies:

• xclip - to send login codes to the X clipboard instead of stdout
• zbar - to parse QR codes from screen with -c option
• qrencode, imagemagick - to display QR codes with -v option

• ga [-x] service - get token for service
• ga -[x]c service - record seed for new service
• ga -[x]v service - view qrcode for service
• ga -l - list services setup

The -x, -xc, and -xv flags disable use of X11 even when $DISPLAY is set, compared to no option, -c, and -v.

Mac OS X users may be using the GPG Tools distribution. For some strange reason, this package doesn't detect when you are running in a terminal session without a display (e.g., SSH), so by default, it always launches a GUI for key entry. Which makes ga impossible to use over SSH on OS X.

To fix this, you'll want to tell it to uses a curses display for passpharse entry:

export PINENTRY_USER_DATA="USE_CURSES=1"

A good way to decide when to export this variable is by detecting it SSH_CONNECTION is a non-empty string.

We are happy to receive bug reports, fixes, documentation enhancements, and other improvements.

Please report bugs via the github issue tracker.

Master git repository:

• git clone git://github.com/scslab/ga.git

David Mazières.