So I lost my OpenBSD FDE password (2016)(words.filippo.io) |
So I lost my OpenBSD FDE password (2016)(words.filippo.io) |
People who advise not using cloud for backups, suggesting cold wallets and whatnot as blanket advice have been harmful by giving way to the orders of magnitude more likely but the catastrophic scenario that is simple data loss.
Some people bash on Microsoft for backing up your drive encryption keys in the cloud for example, but it's the most common failure mode they're trying to address. No thief would access your cloud, no state-level actor would be deterred by lack of cloud (see: xkcd wrench), no rogue employee could make use of your hard drive encryption keys.
Get your priorities based on your threat model, and get your threat model right, people.
However I do agree that "going alone" with security can make us the victim of our own fragility. I can see this happening in the new blockchain world of decentralisation. If I lose my Bitcoin wallet or lose the password, who can I speak with to validate my identity? Nobody. Currently, I can go to the Bank and validate myself with other forms of ID to access my account, but with Bitcoin it's all on me. Imagine losing your entire life savings because you forgot your password or access to your email account.
This is where centralising certain things works for the overwhelming majority of the population. That's not to say that those systems work perfectly, but they are vetted and have laws and regulations to protect us.
Whatever that is if not another system protected by long password you're likely to lose, or that might bitrot past the point of recovery.
Yeah, especially here on HN you hear about people not thinking about threat models. And yes, Denial-of-service by forgetting the password or having it inaccessible is a threat model
That's why I just laugh at the people who think putting everything in a password manager is the best way. It is good, but you need to understand your cases/threats and risks
Sometimes writing it in a piece of paper is the best solution
Backup strategies and good security posture is a "why not both" type of situation. It's harder than it should be, but sometimes that's the cost of doing business.
Microsoft avoids that by backing up your key (not password) to a USB drive or even cloud first. There's no typo issue. There's no forgotten password issue.
In a commercial environment there are ways and means¹ but getting a non-technical user to securely and safely manage access credentials is can be a time consuming education process. Especially after the first time someone comes to you to hack their stuff because they've lost their keys & they never did do that backup thing you good then about³ and you tell them it simply isn't possible.
Even those of us with experience in the field sometimes make mistakes that we can't revert, so people without that experience can be forgiven to an extent for trading security for what they think is safety (but is really just convenience).
Solutions, that don't involve someone being an unpaid 24/7 infrastructure support tech, on a postcard please!
----
[1] if procedures are properly followed² code is in source control and documents are in equivalent storage, the most you should be able to lose is today's work
[2] yeah, I know…
[3] or that uses the same, now lost, credentials
The password is quite a few random characters that I memorized when I first used FDE decades ago and I’ve never had reason to change it.
I rotate my other passwords often and never use this one anywhere other than a boot loader; I don’t even type it into a running operating system to save it.
I’ll never forget it, but if I had to change it then I think I would go with the “battery horse stapler” method of pass phrase.
I used to think that, too. Narrator: He did forget it... Lesson learned. As always, YMMV.
https://en.wikipedia.org/wiki/Playfair_cipher
Not the full cypher but just reading out the letters in the grid in a different direction.
If you're looking for something in between, then deliberately weaker encryption might be what you want, although almost no one seems to mention that much.
A couple years ago someone lent me an Android phone to do some development on (it had some hardware feature I didn't already have on my testing phones). I don't use my main google account on dev phones so I promptly set it up with whatever google generated for me and I forgot both the email and the password.
6 months later I have to give it back, and I hit reset to defaults. Surprise! The phone asks me for the previous account and password!
Back then the feature was new, which is why I didn't know about it. Fortunately, being new it was also buggy.
I managed to complete the factory reset through a complicated process that involved going through accessibility options, replacing some system apk with an older version (via adb i think) and some other trickery that I forget. But the stuff was mostly in the open on youtube.
This being strictly a dev phone, I had no data to lose. It only had on it apps I was working on and thus I had the full source code in git. Still, it was good to not create more ewaste.
I've been paying attention on newer test phones though. I don't think that security feature is as easy to bypass these days...
FDE doesn't protect against remote attacks, and anyone who would physically make off with my devices (a VERY unlikely event) is either:
* A thief who will turn around and sell them to someone who will erase them.
* A state actor who will get the data no matter what I do (and find it of no interest anyway).
The BSDs and Linux have a lot of catching up to do.
Stop putting every BSD in the same basket.
Also, this is Unix, you can put encrypted slices/partitions with ease. You can omit to encrypt the system files and encrypt the data and config partitions.
But FDE avoids tampering.
Telling users that forgot their password that not only do they need to reinstall Windows, but that every single document, photo, video of their grandkids, etc. is now lost forever is untenable. At the same time, FDE is important for security, so what is a reasonable compromise? Allow some form of online recovery options (secured by the full expertise of MS security folks) by linking an account to serve as your 'IT-guy managed AD in the cloud'
The threat of “losing the keys to all the data” is considerably larger than the threat of having your computer and data stolen for an average home user. It can’t just be a matter of more secure is better… you have to have an idea of what you’re trying to prevent.
All of our shit has been lost in one leak or another so at this point it seems like it barely matters.
If you're already in my bedroom, I've got bigger problems than my family photos.
If I leave my laptop on the bus, it's a VISA problem.
This isn't for everybody, but it's probably the safest my family can be.
However, there are better options for users - how about Smartcards? You know, like yubikey / U2F before the web?
You can even use it with LUKS
One step at a time!
1. Back up your data.
2. Test restoring your data.
3. Automate your backups.
4. Automate your test restores.
5. Now you are ready for full-disk encryption.
It is okay if you do not complete all steps. More steps is better. Do not skip ahead.
The recovery key is a 128-bit value (entered as 8 groups of 7 digits, each of which when divided by 11 gives a 16-bit value, where a non-zero remainder indicates the group has been incorrectly entered) which gets hashed repeatedly, with a salt, to derive a 256-bit key that decrypts a copy of the VMK.
Syncing to a cloud service would be better.
So you... put it in USB drive then dig it out 5 years later and discover it's dead and you're fucked.
But my original point was that sealing the key to the TPM is better because it prevents adversaries from accessing the volume data by tampering with the boot chain, and provides a lockout where there are too many failed PIN attempts.
The bruteforce attack described by the author wouldn't have been possible on a BitLocker volume that was set up with TPM+PIN.
The issue is that now the forgotten password moves to the cloud, especially since Bitlocker is activated automatically, without notifying the user, when an MS account is used. So regular Joe probably has no idea his drive is encrypted.
And since MS also push for authenticating to the account by using the TPM combined with a fingerprint / webcam / PIN, if you can't use your laptop (which is likely the case if you can't remember the unlock password – which you've probably never knwon was even a thing to begin with) you're pretty much SoL if you can't remember the cloud password – which you haven't used in months, possibly.
I think the old, manual way of activating BitLocker was best, where they tried to coax you into backing up that key someplace.
That method lead to tons of people not using it. It also lead to tons of drive lockouts due to people not knowing the password and not backing up the key. Good security is transparent to the user, making the user do things makes them insecure.
There are a ton of authentication options for a Microsoft account that aren’t passwords (they are the “passwordless” people after all). You can set up as many as you want (and will be nagged about it until you do!). Install Authenticator, configure whatever your phone offers for biometrics to unlock it, and get on with your day.
I may have assumed that your backups were encrypted, just because so many backup tools do it automatically. And I didn’t put that in the post. Predictably, I get some kind of jerk replying to the comment with a sarcastic jab, rather than any kind of interesting discussion.
Accidental data loss is the big risk, and for most people, it’s a bigger risk than any risk of someone reading your unencrypted data. It makes sense to start with the most serious risks (data loss), and work your way down to the minor risks (compromise).
It makes not sense to start by encrypting your data, because it significantly increases your risk of data loss, in the absence of good backups. That’s what the article is talking about.
If you encrypt your HD, you’re suddenly in a position where forgetting your key will lose all your data. It’s like walking off a cliff and hoping you can fly.
If you start by making backups and doing test restores, there’s a period of time where you are still forced to remember the key (to do the restore), but the consequences for losing it are low.
Most people protect against access by whoever stole their laptop, with Microsoft and TLAs not being considered a threat. Those who do probably don't use Windows in the first place.
Your government might be able to get the key - if that's part of your threat model - but they probably have easier ways to force you to give it up.
Anyway, FDE is often on by default. Do you really believe the average user is going to print out the backup key?! Do even tech savvy users have printouts of all their eg 2FA codes? Anyway, that would have worse correlation of risk as users would probably keep the printout next to their computer.
That is assuming you somehow forget your encryption key but remember the login to your microsoft account... that you used once 2 years ago when you were installing the machine.
It also means anyone that does get the login for your MS stuff can decrypt your laptop
Anyone that does get the login for that MS account can decrypt the laptop, but often times they don't have physical access to the laptop (say some hacker who does not know you personally). If they let people around them get the credential, I think it is likely that they will let others get the encryption key even if it is not saved on the cloud.
And I think backup using the cloud is a nice option, although it would be better to have a master password that you remember and doesn't require writing it down physically. That way people having access to your cloud will not be able to read it, and you still have it when your house burn down (which does happen for some people...).
Especially that most YK versions do support pub/private key auth...
Encryption is designed to make data difficult to access, so it makes sense to consider backups and encryption jointly. I don’t understand why someone would consider this controversial.
Or maybe just capitulate and admit that a bunch of kids, people and cat pictures maybe don't need to sit on encrypted storage
You seem to be arguing against something here, but it sounds like it’s really just a miscommunication. The original prompt was to fit the instructions on a postcard, and and perhaps it’s not really possible to fit good instructions on a postcard.
In order to fit instructions on a postcard, there are a number of things I left out with the idea that someone could figure them out. Stuff like “how do I do backups” or “should I encrypt my backups”. I thought that people could figure out to encrypt their backups if they wanted to, because backup solutions have that option. I also thought that people could figure out that you’d also encrypt your backups if you encrypted your hard drive. Maybe I should have spelled it out in excruciating detail.
As far as I can tell, that’s the lesson here—spell things out in excruciating detail, or you’ll get sarcastic jabs in the replies.