3 ms·

I would argue that your threat-model is wrong in this scenario. EKM isn't there to protect you from the company that you're using, it's to protect both you and

by chias 8y ago

I would argue that your threat-model is wrong in this scenario. EKM isn't there to protect you from the company that you're using, it's to protect both you and the company from legal overreach. I work at a company that does EKM for its customers. It doesn't force us to secure our customers' accounts, it allows us to secure them. We get to say things like "I'm sorry, we are unable to pull this data" rather than having to convincingly argue why we shouldn't. This makes us very happy. Maybe we can be forced to break things in such a way as to eventually get any future data you submit, but that's a whole lot more difficult / expensive for the government than the typical "all ur data are belong to us plz" requests. Yes, if the service provider is malicious, EKM isn't going to save you from them. But if the service provider is not malicious, it can save both you and your service provider.

candiodari 8y ago
Then perhaps I suggest you search Microsoft Skype. Providers can be forced to modify code as well: https://www.google.com/search?q=microsoft+skype+legal+intercept https://www.google.com/search?q=microsoft+skype+legal+interc... Do you seriously doubt Microsoft was forced to include legal intercept in Skype after reading the first 3-5 links there ? So I disagree with your assessment that it provides any protection whatsoever. Perhaps it raises the difficulty a bit.
- geofft 8y ago
  It is a perfectly sensible threat model to exclude government intervention. Perhaps more sensible, on the grounds that the government can always make your life hard in other ways, and the government can get away with not following the law. There are lots of meaningful attackers who are unaffiliated with the government, and it's absolutely worth protecting against them.
  - candiodari 8y ago
    This does not result in a change of threat model at all. That's what I've been pointing out. It does not protect against anyone at all, nor does it make you more vulnerable to them. It does not exclude government intervention at all. The government still has the power to compel a change in the code that works with the encryption keys. When that happens, exclusive access to the keys, to put it mildly, won't matter. If you think differently, let's see you put your actual trust in this process. You keep access to all your encryption keys and passwords, I even promise not to copy them, but you log into your web banking using a web browser I control. Which is the equivalent of the situation discussed here: I control the code interpreting the encryption keys, you control the encryption keys. Depending on your bank's authentication method I may or may not be able to copy the keys, but either way I'll be able to, say, change a bank transfer you make to my liking, which is really the point anyway. So I will transfer a suitable fee for your education, let's say $100, "without access to" your encryption keys to some charity of my choosing. Deal ?

by chias 8y ago

candiodari 8y ago

Then perhaps I suggest you search Microsoft Skype. Providers can be forced to modify code as well: https://www.google.com/search?q=microsoft+skype+legal+intercept https://www.google.com/search?q=microsoft+skype+legal+interc... Do you seriously doubt Microsoft was forced to include legal intercept in Skype after reading the first 3-5 links there ? So I disagree with your assessment that it provides any protection whatsoever. Perhaps it raises the difficulty a bit.

geofft 8y ago
It is a perfectly sensible threat model to exclude government intervention. Perhaps more sensible, on the grounds that the government can always make your life hard in other ways, and the government can get away with not following the law. There are lots of meaningful attackers who are unaffiliated with the government, and it's absolutely worth protecting against them.
- candiodari 8y ago
  This does not result in a change of threat model at all. That's what I've been pointing out. It does not protect against anyone at all, nor does it make you more vulnerable to them. It does not exclude government intervention at all. The government still has the power to compel a change in the code that works with the encryption keys. When that happens, exclusive access to the keys, to put it mildly, won't matter. If you think differently, let's see you put your actual trust in this process. You keep access to all your encryption keys and passwords, I even promise not to copy them, but you log into your web banking using a web browser I control. Which is the equivalent of the situation discussed here: I control the code interpreting the encryption keys, you control the encryption keys. Depending on your bank's authentication method I may or may not be able to copy the keys, but either way I'll be able to, say, change a bank transfer you make to my liking, which is really the point anyway. So I will transfer a suitable fee for your education, let's say $100, "without access to" your encryption keys to some charity of my choosing. Deal ?