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Comment by dguido | Hacker News Reader

I don't care if it's beautiful, or how it auto-saves drafts, I want an e-mail client designed with security from the start. Everyone seems to be up in arms about privacy these days, but people forget both how much data is available inside their mail spools and the fact that none of it is encrypted. Put S/MIME or PGP support in your roadmap as a first-class feature and I'll be interested in your mail client. Consider a text-only mode and develop with a type-safe language and I'll definitely take a second look.

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Encryption is not the be-all and end-all of security. Here is a good example: your boss sends you a signed, encrypted message that just says, "You're fired!" You send that signed message to the secretary you have a grudge against, encrypted using her public key instead of yours. Now the secretary thinks she is fired too (potentially leading to mayhem within the company). This discusses the issue in depth:

http://world.std.com/~dtd/sign_encrypt/sign_encrypt7.html

PGP and S/MIME do not encrypt the subject line of emails; this is an easy way to leak information. You also do not get encryption of References/In-Reply-To headers, and various other headers that can leak information.

You're right of course but I think a straightforward way to sign, encrypt and decrypt your email would be a big step forward.

Plus (nearly) all security has trade-offs. The trade offs dont necessarily trump the added benefits of the security.

Sounds like a simple solution would to duplicate the headers in the body and encrypt them along with the message. That way, even if you resend that email, the encrypted To: field would make it obvious that it was meant only for you.

In PGP and S/MIME, the ciphertext is signed. You don't encrypt a signed message, you sign an encrypted message.

You can't take a signed message that was encrypted with your public key, decrypt it, re-encrypt it with somebody elses public key, and expect it to still appear signed by the original sender when the new recipient decrypts it.

[edit] There are of course serious problems with the lack of header signing/encryption and replay attacks though I agree. Hence why I add a small note at the end of all of the pgp signed comments on my blog: "This signed text was written for https://grepular.com/ only"

Don't such systems generally encrypt first and then sign the encrypted text, specifically to avoid this?

Your points about subject lines and other assorted headers are correct.

The link I provided discusses this as well; not only are there other attacks, but those other attacks are potentially more severe. A man-in-the-middle attacker can claim credit for a message by substituting their own signature for the sender's. A naive encrypt-then-sign system will also lack non-repudiation in some cases (e.g. when using RSA signatures and encryption), and will only provide non-repudiation on the ciphertext itself (not the plaintext; this may or may not be what you want).

AFAIK Yorba uses Vala which is a native C#-like language.

I do agree with you that PGP and S/MIME would be awesome features but most people using Linux are so frustrated with default apps that I think they wanted to show their focus on the basic workflow.

> most people using Linux are so frustrated with default apps

I'm Linux user and don't feel frustrated. Am I missing out?

I've been wondering that as well. Am I missing out on some premium reserve of frustration? I really gotta try harder to feel disenfranchised.

Letting Johnny encrypt[1] sounds like an interesting topic of research, although IMO research probably shouldn't be bound to any particular product until it's no longer research.

[1] http://static.usenix.org/events/sec99/whitten.html

Not sure if I understand you correctly. Wouldn't an email client with good PGP support help Johnny encrypt?

Why don't you do some research before posting FUD? The people planning this project built Shotwell, the default photo organizer for Fedora and Ubuntu. Clearly they know what they're doing. http://en.wikipedia.org/wiki/Shotwell_(software)

I fail to see how them building a photo organizer app has any relevance in his wish for a security minded email application. Sure, the company might know what they're doing, but nowhere in the introduction video did they discuss security - the most talked about points were usability and aesthetics. It seems to me that dguido's comment isn't actually FUD, but rather an observation about their proposal...

Most email is sent as unencrypted text over the Internet.

Secure email is not possible unless you're all being very careful, or you're using some other protocol.

This is why the OP talked about S/MIME and PGP, methinks.

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