Credentials for Linux: Bringing Passkeys to the Linux Desktop

https://alfioemanuele.io/talks/2026/02/01/fosdem-2026-credentials-for-linux.html

by alfie42 • 5 months ago

80 77 5 months ago

digiown13• 5 months ago

Passkey/webauthn is a cool tech, and I'd really like to use it everywhere, but I find the anti-user attitudes of the spec authors concerning. The spec contains provisions about "user verification" (the software must force user interaction) and not allowing the user to access the plaintext keys. It appears that the spec authors do not consider the keys to be owned by the user at all.

KeepassXC implements passkey support, but they do not implement these anti-user features. As a result, they are being threatened with being banned via attestation:

https://github.com/keepassxreboot/keepassxc/issues/10406

https://github.com/keepassxreboot/keepassxc/issues/10407

Screw these "You'll own nothing and be happy" people. I'll own all my keys no matter what. The software I run on my device should never betray me to signal things like "this passkey is allowed to be backed up!".

cadamsdotcom• 5 months ago

Agreed, unfortunately.

Passwords are easy to understand, transparent and portable, and when used with good hygiene (always using password manager and generating unique & strong passwords for everything) there isn’t yet a strong case for anything else.

doubled112• 5 months ago

I’m not happy with everything about passkeys either. I am fine with them as an additional method, but I would never use them as the only method.

That said, I had a much easier time getting my kids onboard with a FIDO2 security key than I would have a password manager.

Enter your email and touch this is easy to understand.

giancarlostoro• 5 months ago

How do you even ban something like KeypassXC given that it is open source and any end user could basically edit KeypassXC and bypass a ban?

Edit: Reading one of those issues it sounds like they want the keys stored in an encrypted way, is that too much to ask for? I dont care about viewing it but it shouldnt be stored in a plain easy to open JSON.

digiown13• 5 months ago

That's the thing, they can't yet.

They are proposing an attestation scheme. I'm not sure the details are out yet, but the authenticator would presumably use one of the hardware security mechanisms (like a TPM bound key) to "certify" its own authenticity along with the challenge.

This will effectively ban all open-source implementations, and end user freedom if widely adopted. Fortunately for us it seems like Apple isn't cooperating here for now, and without Apple signing on, it wouldn't get anywhere.

digiown13• 5 months ago

It's an export format. The storage is always encrypted with the database key. And you can view the key directly anyway just like you can view passwords, and copy it from there.

politelemon2• 5 months ago

ask for

That's the key difference. If it mattered, they would make it part of the spec, not threaten a ban. That's even more concerning, there is a central group of people who get to decide who can and cannot use Passkeys.

Dedime• 5 months ago

Well, it's stored in an encrypted way - in the encrypted password database. Much like a password, everyone already knows not to share a passkey. But also like a password, as the owner, sometimes I want to look at it!

hypeatei• 5 months ago

they want the keys stored in an encrypted way, is that too much to ask for

Well, they are encrypted but the issue is talking about exports. The maintainer of KeepassXC already mentions the issue with that: portability. A backup of such sensitive data (a password manager) is going to be stored somewhere secure (to the user) already. Why would you encrypt the contents and add another layer of complexity that other tools may not be able to handle? I want to be able to rely on those backups in the future and copy paste them around manually if needed. It's user choice, put simply.

A specification committee should never be deciding what a user does with their data, period. The security maximalist is always going to advocate for the most secure thing but most of the time that's not practical or friendly to humans.

signal112• 5 months ago

Shafting open source projects that implement your spec is not okay, and is terrible optics.

Tech journalists should ask the FIDO Alliance if they’re just Google+Apple+Microsoft in a trenchcoat. Definitely not very open!

digiown13• 5 months ago

I do get that there are use cases for actual hardware bound keys for enterprise settings. But having non-exportable credentials (effectively non-ownable) is not acceptable in a consumer setting. This is a thinly veiled attempt at strengthening platform lock-in.

Look, the spec says you can't export the keys to a file! Too bad, go re-register your 120 websites if you want to stop using iCloud/Google!

politelemon2• 5 months ago

It appears that the spec authors do not consider the keys to be owned by the user at all.

This was my impression, and it explains why the original announcement involved companies that would benefit the most from keeping their users on a leash.

AndrewDucker• 5 months ago

They don't consider the key to belong to the user. The key is a token generated by the site to allow it to identify a user. In order for them to do perfectly so they do not want users to be able to tamper with them, leak them, or do anything which might violate their assumptions about the key.

mzajc2• 5 months ago

No, the private key is generated and stored client-side, and never sent to the server. Even if that wasn't the case, how I store my credentials is none of the websites' business, and my own hardware should do as I say.

FreakLegion4• 5 months ago

I'm replying to this post, but your other posts throughout the thread have similar misunderstandings.

User presence tests are an anti-malware feature. The point is that a machine can be compromised without letting bad guys log into your accounts willy-nilly. Is it a super useful feature? No. The bad guys can steal the tokens for accounts you're actively logged into anyway. But that's why the test exists.

The whole back and forth about plaintext keys is pretty much people talking past each other. Approximately nobody thinks users shouldn't be able to access their keys in the general case. FIDO just wasn't originally designed for the general case (see Operation Aurora). Now it's playing catch-up.

KeePassXC is not "being threatened with being banned via attestation". Attestation requirements are set by the service you're logging into, and KeePassXC is already locked out where those requirements exist (pretty much exclusive to a small number of corporate and government orgs). A random guy from Okta is not threatening to ban KeePassXC.

digiown13• 5 months ago

Approximately nobody thinks users shouldn't be able to access their keys in the general case

Citation needed. To me it seems to be the quiet part that they aren't saying out loud. If it's just a consequence of the spec being unfinished, then they shouldn't threaten to ban KeepassXC for this. The purpose of a system is what it does, and commercial passkey implementations lock users out of their credentials and uses it to strengthen vendor lock-in.

Is it a super useful feature? No

It's security theater and a way for websites to annoy users unnecessarily.

KeePassXC is not "being threatened with being banned via attestation".

https://github.com/keepassxreboot/keepassxc/issues/10406#iss...

It's a thinly veiled threat. Making a certification process and refusing to certify KeepassXC is exactly the same as banning it.

zamalek• 5 months ago

The problem with plain text access (on hardware devices) is that it allows cloning. That is more hostile to users, but it is a stronger security posture. You're supposed to have a backup device somewhere secure, but of course there are many websites that didn't get the memo and only allow a single device.

veeti• 5 months ago

That's a nice thought but how does it work in practice? Every time I sign up for a new service I have to dig up my "backup device" from the safe just to enroll it?

Google Authenticator used to be this way: no backup and restore, as if I'm going to spend a day setting up dozens of TOTP codes again and again every time I change phones. Thankfully, sanity has prevailed since then.

notepad0x903• 5 months ago

I just wish more people would protest this instead of things like secure boot.

Password managers and/or operating systems can manage private keys just fine. websites shouldn't be concerned with how the keys are managed, or be able to make demands on how users store credentials, or know device details for users.

One thing I dislike even with systems like FIDO2 is that the websites/apps can block list your FIDO key's vendors. Similar trends suck. Passkeys are just one iteration in a long line of systems designed with corporate interests in mind.

The system validating the authentication needs only to verify that the credentials are correct. If users want to use TPMs, HSMs,etc.. or none at all, that's up to them. And no information, other than what is strictly required to verify the credential should be transmitted over the network. a signature of challenge data from the app should be sufficient. the user's public key shouldn't be signed at all by hardware, a trusted 3rd party,etc.. the registration process should take care of establishing public key trust to the authenticator/app. The whole thing feels insidious.

digiown13• 5 months ago

Corporate interests HATE general purpose computing, and the freedom to run what you want. With that freedom, you can hurt their interests by blocking ads, stripping out spyware, or avoiding giving up your privacy, and they can't let you have that.

It's a death by thousand cuts that's finally starting to come together:

- Remote attestation like Play "integrity"

- Hardware backed DRM like Widevine

- No full access to filesystem on Android, and no access to filesystem at all on iOS

- No ability to run your own programs at all on iOS without Apple's permission.

- "Secure" boot on Android and iOS that do not allow running your own software

Ever wondered why Windows 11 have a TPM requirement? No, it's not just planned obsolescence.

If they get their way, user-owned computers running free software will never be usable again, and we'll lose the final escape hatch slowing down the enshittification of computers. The only hope we have is that they turn up the temperature a little too quickly that normies would catch on before it gets far enough.

hparadiz4• 5 months ago

Windows 11 has tpm required to enforce full disk encryption that is pinned to a given machine. Linux would do well to do the same thing. It's possible but almost no one does it.

madphilosopher• 5 months ago

General purpose computers, copyright, a free society. Pick two.

dTal2• 5 months ago

Don't forget an entire new category of computing, AI, which is teetering on the edge of requiring processors from one manufacturer, which in turn requires gigabytes of closed-source runtime. Today, you can do functionally more with a computer with an nVidia chip, driven by their binary blobs, than with any other hardware - even though the application software is usually Free. It's a dangerous situation. We are so used to general purpose compute substrate being "free software friendly", but this amounts to a new type of CPU that categorically requires a closed-source OS to be useful.

jmclnx• 5 months ago

I fully agree, seems Linux is heading directly towards being a Windows Clone. So far all the windows crap can be easily avoided, but once these things are forced on me, it is bye bye Linux.

Already I use BSD on an older laptop probably 40% of the time. Linux on my main system is there due to a hardware device issue BSD still have a minor problem with it. But for me right now, Linux seems to be heading in a wrong direction.

digiown13• 5 months ago

KeepassXC implements passkeys in a respectful way. I don't see how this is "Windows crap". If they want to force attestation on passkey implementations, whether or not Linux supports it will not matter.

dgxyz2• 5 months ago

Oh that's not even the worst of the stupid shit.

When you have Apple managing your keychain, your passwords stored in that, your passkeys stored in that, them filling in your MFA info by reading your email and SMS on every device, supplying your primary email account and all your throwaway addresses, and possibly trying to tie you into their OAuth or whatever for a third party, you are fucked if something goes trivially wrong.

waterTanuki• 5 months ago

Hi, I'm one of those people.

Welcome to being a human being, where you need dozens of different accounts and passwords and passkeys and authenticators to live in modern society.

Apple passwords just work. They integrate nicely with most websites where I can authenticate using biometrics instead of copy-pasting and leaving my credentials on my clipboard.

And let's be real here, no one else in the industry comes even close to the amount of investment, research, and maintenance of security platforms than Apple. I would not bet against Apple's security failing.

Everything is a tradeoff between convinience and security. I think Apple's password manager is the perfect middleground. I let it generate different passwords for every site, store my passkeys etc.

No one has the time to fully optimize their security footprint. No one. And if you do you're either A) working in a sensitive area that requires it for your job or B) being targeted by state-level threat actors or C) lying. Anything beyond a password manager + 2fa is severe overkill for anyone else.

7bit2• 5 months ago

Okay, a

jsiepkes• 5 months ago

The system validating the authentication needs only to verify that the credentials are correct. If users want to use TPMs, HSMs,etc.. or none at all, that's up to them.

That's not up to the user in a corporate environment. If you use company supplied hardware keys for FIDO2 you don't want users using some software emulator on their phone because they think it's easier.

7bit2• 5 months ago

Websites blocking FIDO vendors is nothing new. In corporate environments this may be necessary. Imagine a 2-tiered environment where generally all vendors are allowed (no blocks) for accessing tier-1 information, but to access tier-2 you need a special vendor. That is not uncommon.

By the way, SAML has similar authentication restrictions, so this is not something FIDO came up with.

hexo• 5 months ago

No thanks, it stinks.

shmerl• 5 months ago

That's interesting. How the actual passkeys will be stored with this approach?

flumpcakes• 5 months ago

I'm a big fan of passkeys, but they are currently harder to manage/reason about than passwords (even autogenerated ones stored in a password manager).

My web browser wants to own the passkeys, my OS wants to own the passkeys, I have to deny them before I can get to my hardware key. Some providers will sync passkeys amongst devices, which at some point seemed to be against the spec.

It's all rather confusing. I wish there was a straight forward best practise that can be followed without the niggling worry that you're doing it wrong, or that you might get locked out of services.

ianburrell• 5 months ago

Storing passkeys in password managers is the best option. It isn't as secure as hardware tokens, but it solves the problem of managing multiple keys and losing the tokens.

Passkeys are better passwords since not vulnerable to phishing, and it makes sense to store better passwords in password manager.

hedora• 5 months ago

Here’s a list of “transports” which (I think) are storage backends that manage the passkeys (preventing the user from controlling their own credentials).

https://github.com/linux-credentials/libwebauthn?tab=readme-...

Anyone have any idea how hard it is to add “text file” or (god forbid) “TPM with user supplied keys” to the list?

(The latter would let you backup your keys securely, and then recover them by using the keys, which you backed up elsewhere.)

chaz6• 5 months ago

Are there any passkey hardware tokens the private key is effectively irretrievable? That is why up to now FIDO U2F has been my preferred additional factor. The down side is that you have to register multiple tokens for each authentication service in case one is lost or damaged. I miss the days of openid when I could use my own idp with any service, but the walls quickly went up when the big players wanted to control the ecosystem.

Credentials for Linux: Bringing Passkeys to the Linux Desktop

Related Stories