Let's Encrypt: How It Works • Hacker News Board

Re: Let's Encrypt: How It Works

#121

Post by schoen » Sat, Nov 22, 2014, 9:38 PM UTC

mappu wrote: post #68

schoen wrote: post #39

Earlier quoted context omitted.

We are actually hoping to have packages shipping from the official OS repositories, so you won't even have to get the package from us. (If anyone wants to help with this aspect, please get in touch.)

Is it possible to get new packages into Jessie post-freeze?

I don't think it would make sense to start shipping this package in operating systems before public cert issuance starts, which is currently expected to be around next summer. It would be fairly confusing to web developers to be encouraged by the OS to run the client, only to have it immediately inform them that there are no CAs yet able to issue certs to them!

Re: Let's Encrypt: How It Works

#122

Post by duskwuff » Sun, Nov 23, 2014, 7:51 AM UTC

amatix wrote: post #91

Does it deal with the case of SaaS apps for customer domains? Eg. Customer example.com rocks up to my SaaS app and wants to use myapp.example.com - currently creating

Yes. As the service provider, you can create a DNS record to verify "myapp.example.com", which is sufficient to get a certificate issued for it.

For a setup like this, you may still be better off getting a single wildcard certificate for "*.example.com", which (as far as we know currently), isn't possible through Let's Encrypt. But it's certainly possible to get these certificates through Let's Encrypt.

Re: Let's Encrypt: How It Works

#123

Post by adamtj » Mon, Nov 24, 2014, 6:27 PM UTC

How is this not really bad?

Suppose I somehow get control of a machine on the same network as a server that doesn't use Let's Encrypt. I can probably ARP spoof it pretty easily. If it has a signed certificate from a different CA, I can't MITM it without people noticing. Or I couldn't, until now! Because I can now "control" the server's responses, I can easily get Let's Encrypt to authorize a new key pair giving my control over that domain. I can now generate valid certs for my MITM keys.

If the server were already using Let's Encrypt, I couldn't create a new controlling key pair. The "How It Works" doesn't talk about that, but search the RFC for "recovery token". But if the server isn't using Let's Encrypt, what would stop me from doing this?

Of course, I'm actually on the other end of it. To project myself, do I really have to at least register a controlling key pair with Let's Encrypt and any other browser-supported CAs that adopt this protocol?