FUTURE DEVELOPMENT ON https://git.sr.ht/~mcepl/gen-oath-safe

gen-oath-safe

Create OTP secrets, uri, qrcodes, configurations for TOTP and HOTP authentication.

Licensed under the MIT License <https://mit-license.org/>

Copyright (C) 2013 Richard Monk <rmonk@redhat.com>
Copyright (C) 2013-2014 Matěj Cepl <mcepl@cepl.eu>
Copyright (C) 2016 Thomas Zink <tz@uni.kn>

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or
sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice shall
be included in all copies or substantial portions of the
Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR
A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.

gen-oath-safe can create hex and base32 secrets used for TOTP/HOTP two factor authentication (two-step verification), used in many services and applications. It can be used both on the server to generate server-side configuration, and on the client, to generate the configuration for authenticator apps and hardware tokens.

The script can use an existing hex encoded secret or creates a new random secret. Based on the secret it produces a otpauth URI to create a QR code which is print on stdout and which can be scanned by authenticator apps (like Google Auhtenticator, FreeOTP, Yubico Authenticator, Aegis Authenticator). The script also outputs the configuration used by server-side authentication services like Apache mod_authn_otp, pam_oath, and linOTP/PrivacyIdea. If Yubikey packages are installed, and a Yubikey is inserted, the configuration can be directly written to a free slot (for hotp) or the oath module (for totp). If no Yubikey is inserted, the corresponding commands to program the key are output on stdout.

Backup your hex secrets safely (e.g. in an encrypted container) to be able to restore the configurations.

Requirements

• xxd, base32: to convert the hexadecimal secret to base32
• qrencode (optional, recommended): to create the qr code from the uri and display it on stdout.
• yubikey-personalization (optional): to probe for Yubikey and write hotp configuration to the Yubikey slots.
• yubikey-manager (optional): to write totp configuration to the Yubikey oath module.

Installation and Usage

Install

To install simply put gen-oath-safe into your $PATH. Or run the following commands:

$ install -Dm755 ./gen-oath-safe /usr/local/bin/gen-oath-safe 
$ install -Dm644 ./gen-oath-safe.1 /usr/local/man/man1/gen-oath-safe.1

For Arch, there is a package in the AUR:

$ yay -S gen-oath-safe-git

Usage

To output usage and help use:

gen-oath-safe -h

Synopsis:

gen-oath-safe [issuer:]<username>[@domain] [tokentype] [secret]

The username can either simply be a user, or include the issuer and domain, e.g. github.com:gituser@github.com.

The tokentype is either totp (default) or hotp.

The secret is a hex encoded OTP secret. If not provided, a random secret is generated.

References

• “HOTP: An HMAC-Based One-Time Password Algorithm” http://www.ietf.org/rfc/rfc4226.txt
• “TOTP: Time-Based One-Time Password Algorithm” https://www.ietf.org/rfc/rfc6238.txt
• mod_authn_otp https://github.com/archiecobbs/mod-authn-otp
• pam_oath https://wiki.archlinux.org/title/Pam_oath
• linOTP https://linotp.org/
• Aegis Authenticator https://getaegis.app/
• FreeOTP https://freeotp.github.io/
• Yubico Authenticator https://www.yubico.com/products/yubico-authenticator/