age-plugin-yubikey VS lastpass-cli

_o/ hi all, age author here!

The OP link is the spec, here's a few other things you might find interesting

- the Go reference implementation https://age-encryption.org

- the Go library docs https://pkg.go.dev/filippo.io/age

- the CLI man page https://filippo.io/age/age.1

- an interoperable Rust implementation by @str4d https://github.com/str4d/rage

- a YubiKey plugin by @str4d https://github.com/str4d/age-plugin-yubikey

- the draft plugin protocol specification (which we should really merge) https://github.com/C2SP/C2SP/pull/5/files?short_path=07bf8cc...

- a Windows GUI by @spieglt https://github.com/spieglt/winage

- a discussion of the authentication properties of age https://words.filippo.io/dispatches/age-authentication/

- a discussion of a potential post-quantum plugin https://words.filippo.io/dispatches/post-quantum-age/

- a password-store fork that uses age instead of gpg https://github.com/FiloSottile/passage (see also: how I use it with a YubiKey https://words.filippo.io/dispatches/passage/)

I am using the yubikey plug-in for age (https://github.com/str4d/age-plugin-yubikey). It creates a private key and writes it to one of the retired PIV slot. What I want to do is to write the same private key to two different Yubikeys.

So with age I can also just use my ssh public key to encrypt and my ssh private key to decrypt my files. If I want to get fancy, I can use something like https://github.com/str4d/age-plugin-yubikey to provide the key material for my age operations (which should compose with age.el quite well also, i.e. you can have every decrypt operation have a touch requirement in Emacs that way).

> A good feature of PIV applet of Yubikey 5 is that it stores 24 keys.

Note that not all 24 of those keys are suitable for age usage. The 4 main keys have specific usage definitions in the PIV specification that mean hardware tokens alter how those key slots behave. Only one of them (the KeyManagement slot) has a definition that allows encryption, and even that I was somewhat suspicious of overlapping with, as I couldn't predict how those existing keys were being used, and didn't want to support every possible key type that might be in that slot (which users likely wouldn't be able to alter).

age-plugin-yubikey avoids this complexity by only interacting with the 20 "retired" slots, which have no constraining definitions. (I am considering adding restricted support for the KeyManagement slot specifically for CAC card users who aren't allowed to add new keys to their cards [0], but this would be behind a default-off feature flag to keep the primary UX simple.)

[0] https://github.com/str4d/age-plugin-yubikey/issues/62

We designed the plugin protocol (https://hackmd.io/@str4d/age-plugin-spec) and generally the age recipient/identity structure specifically to enable the use of hardware or remote keys!

For example, https://github.com/str4d/age-plugin-yubikey makes it very easy to use PIV tokens, including YubiKeys, with age. (Well, for now with rage, since plugin support is coming in age v1.1.0.)

I argue against password-protecting keys by default because, unlike using hardware tokens, it doesn't protect against many threat models.

Hardware? I assume if someone was concerned about key access they wouldn't want keys on their filesystem at all but move them into an HSM instead. Since age identities can come from standard input I assume it'd be feasible to put together a workflow there coming from one of the various cli utilities for interacting with keys. There is already a YubiKey specific age plugin [0] getting worked on as well. Currently in beta but looks interesting. Hopefully that will continue to expand to cover other common options. HSM support is pretty important for a modern encryption utility IMO but unfortunately the landscape is pretty all over the place too, so makes sense to just leave it to plugins or as part of a unix flow.

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0: https://github.com/str4d/age-plugin-yubikey

age also has a notion of plugins, one of which is age-plugin-yubikey (written in Rust, there is also yubage written in Go) which allows you to create an age identity whose private key is stored via PIV.

The other difficulty is it appears there is little-to-no support for API/automation:

https://github.com/lastpass/lastpass-cli/issues/602

https://github.com/lastpass/lastpass-cli/issues/624

https://github.com/lastpass/lastpass-cli/issues/604

...their CLI tool is de-facto deprecated (unsupported) and has several unreliability issues (ie: `lpass ls/userls ...` reports differing amounts of values depending on when a user was added to the folder or not). Basically `lpass ls ... | xargs -n1 ...` cannot be trusted, and you can only get an accurate list of passwords (or users) from the actual GUI.

It makes automation, auditing, reporting, near impossible.

When saving the CSV, do not copy-paste the content of the HTML manually, instead use the popup to download the file that LastPass provides. You might need to allow popups for LastPass extension the first time you perform the export, then perform another one to get the popup.

# 2. Export attachments

Use lastpass-cli to export attachments. A script is provided in version 1.3.4: https://github.com/lastpass/lastpass-cli/blob/v1.3.4/contrib...

https://github.com/lastpass/lastpass-cli/blob/master/contrib/lpass-att-export.sh helped me batch-export my attachments.

You can see the source code for a lastpass client here.

(define-module (lastpass-cli) #:use-module (guix utils) #:use-module (guix packages) #:use-module (guix download) #:use-module (guix build-system cmake) #:use-module (guix licenses) #:use-module (gnu packages bash) #:use-module (gnu packages curl) #:use-module (gnu packages xml) #:use-module (gnu packages gnupg) #:use-module (gnu packages pkg-config) #:use-module (gnu packages tls) ) (define-public lastpass-cli (package (name "lastpass-cli") (version "1.3.3") (source (origin (method url-fetch) (uri (string-append "https://github.com/lastpass/lastpass-cli/releases/download/v" version "/lastpass-cli-" version ".tar.gz")) (sha256 (base32 "06v7d1khk5ylhmf1giqpgq97gsn6mnqhg0637gnryv704wb5jkxr")))) (build-system cmake-build-system) (arguments ;; disable tests? '(#:tests? #f)) (native-inputs (list pkg-config)) (inputs (list bash openssl curl libxml2 pinentry)) (synopsis "Command line interface to LastPass.com") (description "") (home-page "https://github.com/lastpass/lastpass-cli") (license gpl2))) lastpass-cli

Their CLI seems to support showing attachments: https://github.com/lastpass/lastpass-cli/blob/8767b5e53192ad...

FYI for those interested in CLI password management, there is a pretty good CLI for LastPass called lpass that even supports your Yubikeys.

https://github.com/lastpass/lastpass-cli