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Comment by akerl_ | Hacker News Reader

> For better or worse, the status quo is that there is no signaling mechanism in openpgp (or keys.openpgp.org) at the moment to specify how a key should be used, so publishing a key is just a yes or no situation.

Given that, why would it make sense for a service to assume that publishing a key signals that they should use it by default for a given communication channel?

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> Given that, why would it make sense for a service to assume that publishing a key signals that they should use it by default for a given communication channel?

Why else would one publish a key and make it discoverable, if not that it be used?

There are multiple uses for keys.

I've published a key so that people can verify the signatures on some software releases. I don't expect anyone to try sending me an email encrypted with that key. And I really wouldn't expect such an email to work.

And that is why there is different types of subkeys, which you are told about when generating the keys, and every "getting started" guide I've found. If you don't want to receive encrypted emails, don't share a subkey for encrypting email?

What's the subtype that's for encrypting emails? Last I looked, there's a subtype for encryption, with no specificity for what medium.

Not for email specifically, but there is a flag for encrypted communications and another for signing.

https://datatracker.ietf.org/doc/html/rfc4880#section-5.2.3....

I believe separate keys for encryption and signing is the default in most implementations.

Sure, but there are things for encryption other than email. Publishing an encryption key does not imply that emails sent to me should be encrypted to that key.

Yep, same. I find it funny that I'm apparently un-emailable by anyone on Proton. Good thing no one actually uses email for communication.

For example, so that they could sign documents with the private key and have people be able to validate them.

Another situation might be that, yes, the user wants encrypted mails, but are debugging their setup, part of which activity is uploading their key to openpgp.org. Until they get their stuff working, they don't want encrypted mails from the wild.

A related situation might be that something breaks in the setup of a user who receives encrypted mails. They'd like to pause them and get regular mails, without the hassle of deleting the key.

It’s used for more than just email. For example, you can sign packages on for Pacman on Arch Linux with GPG (https://wiki.archlinux.org/title/Pacman/Package_signing), and they have you configure public key servers, which includes openpgp. Now, if I had set that up for package signing and other personal uses (like SSH keys, git commit signing, etc), that doesn’t mean I have my email set up to be encrypted.

You should 100% be able to set a flag on the key server what you are set up to automatically receive using the key.

There is a key for encryption, signing, authentication and certification in OpenPGP. The flags are C, E, S, A. The use cases are separate.

Perhaps another flag for automatic vs non automatic would help.

Encryption is not just for encrypted emails.

In theory. In practice, published PGP encryption subkeys has only seen adoption in emails.

Besides, is the criticism that people are using published keys for email? It seems people are outraged that they received encrypted data using keys that they themselves advertised. The specific medium for data transfer doesn’t seem to matter here.

There are separate flags for communications (like email) and storage (like files).

https://datatracker.ietf.org/doc/html/rfc4880#section-5.2.3....

Great, but while the encryption vs signing choice is presented by common software (albeit in a way that does not make this consequence clear), it completely does not present the encrypt for communication and encrypt for storage options.

I think the point is that it isn't an opt-in process as it should be. The default shouldn't be "if it exists use it".

And yet that’s how browers use TLS. If you enter an HTTP address, they switch it to HTTPS when available, without asking the user “do you want to encrypt your access to this website?” each time.

So people in situations with a specific need for extra security can use them. When publishing it, this meant anyone who 1) explicitly joined the PGP ecosystem and has some understanding of it and 2) explicitly enabled encryption for this specific email or recipient. Neither are the case with what Proton is doing.

Seriously Proton, just add a god damn prompt! And while you're at it, submit an RFC for a "please use by default" field in certs. Bonus points for a "this key is on a yubikey in a safe so if you use it you better have RCE in production to report" field as well or, hell, just a "key description" text field that clients can show the sender before using the key.

Our goal is to make email encryption more usable and less niche, and not only for "situations with a specific need for extra security" - because people shouldn't have to think about which of their emails are and aren't security- or privacy-sensitive.

Could you imagine if individual users had to opt-in to using TLS? Nobody would use it. The large push for using TLS everywhere has helped internet security a lot. Enabling the use of OpenPGP everywhere would also help much more than serving the use case of "this key is on a yubikey in a safe", because almost nobody is going to do that anyway.

Would you also make TLS opt-in for each website?

TLS is opt-in for each website. If a web server doesn't specifically listen with a TLS certificate, users don't connect with one.

Browsers will often attempt that connection, and then tell the user ~"Hey we tried to connect with HTTPS, but the server didn't respond. Do you want to try an unencrypted connection"

But there's no case where Chrome will look and see "oh look, akerl has published a cert on this other site, we're going to just send traffic encrypted to that cert when we connect to his website".

KOO is opt-in for each recipient. The recipient has to upload a key to KOO.

Obviously, OpenPGP works differently from TLS, and TLS does not have a concept of key servers - but key servers are absolutely not a new invention for OpenPGP, and it shouldn't be surprising that if you upload your key to one, you might get an encrypted email.

Usually by random action completely unrelated to emails they forgot about a few years ago.

I dunno, you'll have to ask Proton about that. Presumably they think it is what their users want, and they may or may not then be right about that. This feature has also been active for a few months only, so it might also change with further insight.

Indeed, our mission is to make it as convenient as possible to send and receive secure emails. Of course, this outcome (unexpectedly receiving blank emails) was not intended, and we'll see if we can improve the experience.

Rolling out end-to-end encryption in a federated system where it wasn't there before, is hard :) But we're trying to do so, anyway.

I'm just kind of wondering how this wasn't discovered or why it wasn't fixed in testing?

Well - note that OP uploaded a key to keys.openpgp.org, and then seemingly forgot about it and lost the private key (or at least they couldn't decrypt encrypted emails, and their email client - not Proton's - showed them as being blank). So it's not a scenario that we explicitly tested for, and not something we can unilaterally fix completely - although we can try to make it clearer for the recipient why the message was encrypted and with what key, of course.

> Well - note that OP uploaded a key to keys.openpgp.org, and then seemingly forgot about it and lost the private key (or at least they couldn't decrypt encrypted emails, and their email client - not Proton's - showed them as being blank). So it's not a scenario that we explicitly tested for, and not something we can unilaterally fix completely - although we can try to make it clearer for the recipient why the message was encrypted and with what key, of course.

OP claims to have no memory of having gone through the steps in the published draft standard. The steps involved are at least somewhat more rigorous than merely submitting a key and address to a database, so I'm leaning toward believing OP and questioning the database, especially since the project appears only to have been started in 2019 so completely forgetting having ever gone through such a process seems less plausible than questioning the database.

Further suspect may be the standard, itself (hence "draft"). Why it doesn't require a domain to publish a policy per address for the domain or at least publish that the domain approves usage of the policy seems a rather large oversight* given how it can break email, so this still leads me to be suspicious of Proton as draft standards should be considered "beta", and passively be explicit opt-in (no prompts - user must dig somewhere into the settings to enable).

* I've only briefly skimmed it, so maybe I missed the part covering this.

It's possible that some software did it on their behalf; I believe GPGTools submits keys to keys.openpgp.org, for example. (However, I don't know what the UI flow looks like, it's possible that it could be made clearer what.)

Also, the WKD draft has nothing to do with what's going on here. KOO is not the same thing as WKD, and is not in beta. It's a key server, and the concept of key servers has been around for ages. (WKD has been quite widely adopted as well, despite being only a draft, but that's an orthogonal discussion. It would definitely be better if it became an RFC.)

Somehow, I think either we are reading different articles or one of us has a severe reading comprehension problem. I reviewed what the author wrote and the links and read through the Proton document, and I can't figure out where I have a conceptual error, because the document states WKD, which means the published protocol must have been used or the protocol violated, which what you are describing would be out of spec from the protocol.

The author mentioned WKD but was mistaken. The culprit was keys.openpgp.org, not WKD.

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