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MiniLock – File encryption software that does more with less

minilock.io

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Re: MiniLock – File encryption software that does more with less

#61

Post by BuildTheRobots »

selimthegrim wrote: post #55
achivetta wrote: post #54

I think the hesitations about passphrase being subject to brute force, rainbow table, etc. are warranted, but I have another concern: If my passphrase gets compromised, I have to retire the keypair. That's true of a key file with current asymmetric systems; but, presently if the passphrase of my GPG private key is compromised (e.g. by a hardware key logger), I only have to change the passphrase and ensure the old key…

I actually approached Kobeissi with this point in the meeting in Noisy Square right after the talk, suggesting he integrate a TPM into his key management system (like how you can call out to one in Firefox for SSL with libpkcs5.so or some similarly named library). He responded that the specs were open enough that anyone could add that in. As to a centralized place your guess is as good as mine. Also can MacBook users…

Depending on who you're protecting against you might want to _really_ avoid trusting your TPM.

Re: MiniLock – File encryption software that does more with less

#62

Post by chacham15 »

rgj wrote: post #56

Relying on a passphrase only is not good enough. Enter it once on a compromised system and it's game over. Since your ID is tied to your passphrase you even have an issue and you will need to revoke your public key. Many years ago, people realised you need to rely on something more than knowledge (of a password/passphrase) alone. Pick any two out of {something you know,something you own,something you are}, the latter…

> Enter it once on a compromised system and it's game over

The same is true of any heavily used system today. All systems: banks, credit cards, facebook, etc. use "something you know". "Something you own" has just recently picked up steam in the form of two factor authentication, but then again, how many people you know actually use that?

The only thing that I know of/heard of that might hold up against the type of attack that you describe is the behavioral keys: i.e. a key which is something about you that you dont necessarily know yourself, e.g. your style of chess, or your phrasing of sentences.

Re: MiniLock – File encryption software that does more with less

#63

Post by chacham15 »

diafygi wrote: post #33
akerl_ wrote: post #32

Earlier quoted context omitted.

Except that since there's no salt or other measures involved, there isn't even a trivial protection against rainbow tables letting me create one table and crack all the passwords. It's using ECC as a fun buzzword but tossing all the actual realworld benefits of key-pair crypto out the window by having a single user-provided string map to a single keypair.

Alright, what do you propose? As I said, dealing with keyfiles is HARD for the lay-user.

Why not just store the salt with the data in the same file? Its not as though the program needs to maintain the files' binary compatibility with anything since the encrypted file isn't supposed to be readable by any other program other than the decryption program.

Re: MiniLock – File encryption software that does more with less

#64

Post by higherpurpose »

BuildTheRobots wrote: post #61
selimthegrim wrote: post #55

Earlier quoted context omitted.

I actually approached Kobeissi with this point in the meeting in Noisy Square right after the talk, suggesting he integrate a TPM into his key management system (like how you can call out to one in Firefox for SSL with libpkcs5.so or some similarly named library). He responded that the specs were open enough that anyone could add that in. As to a centralized place your guess is as good as mine. Also can MacBook users…

Depending on who you're protecting against you might want to _really_ avoid trusting your TPM.

Yeah, I wouldn't trust the TPM - certainly not from a Windows machine, and not even an Apple one after the recent revelations/research, which shows Apple tries to make the device secure against "regular" hackers, but very easy to access by Apple itself or the US government.

Re: MiniLock – File encryption software that does more with less

#65

Post by ZoFreX »

MichaelGG wrote: post #40
akerl_ wrote: post #32

Earlier quoted context omitted.

Except that since there's no salt or other measures involved, there isn't even a trivial protection against rainbow tables letting me create one table and crack all the passwords. It's using ECC as a fun buzzword but tossing all the actual realworld benefits of key-pair crypto out the window by having a single user-provided string map to a single keypair.

Please enlighten us on how to generate rainbow tables for passphrases. Assuming they use a lower bound of 6 bits per character, a 100 bit phrase is 46 characters long. Off the top of my head, I'd use a book of quotations, popular lines from movies, etc. And try to hit common permutations of each. So there's a bit of low hanging fruit. But that could be detected when they generate their key. Remember, salt doesn't rea…

> Please enlighten us on how to generate rainbow tables for passphrases.

Pick P, the set of passwords, to be something like "4-6 dictionary words appended". Pick R, the reduction function, such that it maps from a hash to a random value in P.

Re: MiniLock – File encryption software that does more with less

#66

Post by DiThi »

MrUnknown wrote: post #53
SomeCallMeTim wrote: post #50

Earlier quoted context omitted.

They aren't sending the PASSWORD in the clear, they're sending (effectively) a public key. Bob sends public key to Alice. Alice uses public key to encrypt file and sends to Bob. ONLY Bob can decrypt the file (using his PRIVATE key). If you sent a password, then anyone who intercepted it AND the encrypted archive would be able to decrypt it.

seems that how they generate the keys, it's basically the same. The same password would generate the same keys. Anyone who uses the same password would be able to decrypt data sent to anyone else using the same password. Am I understanding this correctly?

If I send you an encrypted file with minilock, you won't know my password, and I won't know yours, but you'll be the only one that can read it, and also you'll be sure I've sent it and not anyone else.

Public key crypto has more advantages and users should understand the basics. This introduction may be more clear (4:30) https://www.youtube.com/watch?v=vMiBwMHcSn0

Also I would only use their 7-random-words feature for passwords.

Re: MiniLock – File encryption software that does more with less

#67

Post by 178 »

simik wrote: post #6

Small UX nitpick. You can't select the miniLock ID by double-clicking it. I think it was one of the reasons bitcoin used Base58 encoding.

Afaik the main reason for base58 is making it impossible to mistake an 'I' for an 'l', etc. Beeing able to always double-click is a nice added bonus, though.

Re: MiniLock – File encryption software that does more with less

#68

Post by thibauts »

akerl_ wrote: post #42
MichaelGG wrote: post #40

Earlier quoted context omitted.

Please enlighten us on how to generate rainbow tables for passphrases. Assuming they use a lower bound of 6 bits per character, a 100 bit phrase is 46 characters long. Off the top of my head, I'd use a book of quotations, popular lines from movies, etc. And try to hit common permutations of each. So there's a bit of low hanging fruit. But that could be detected when they generate their key. Remember, salt doesn't rea…

Assuming they were actually keeping the contents of such wordlists out and actually ensuring high-entropy passphrases, we would be in an OK place, though still far removed from the security provided by randomly seeded ECC keypairs. But that's not the case: https://github.com/dropbox/zxcvbn/issues/39 And as an attacker, I'm using my rainbow tables specifically to target the low hanging fruit. It gives me the best init…

Anyway what will be easy to remember for a human will be sequences exhibiting high ngrams correlation, which is efficiently modeled by markov chains. Wondering if studies have been done from this perspective on password strength, and how chains generated from leaked password / passphrase collections would deviate from ones generated from common language.

Re: MiniLock – File encryption software that does more with less

#69

Post by thibauts »

lolbrainwallets wrote: post #8

This is a bad cryptosystem which will result in people being fucked. Take it offline. A serious known weakness of zxcvbn is that it will grossly overestimate the entropy of things like quotes, lines from songs, lines from movies, etc. "the quick brown fox jumps over the lazy dog" has 111 bits of entropy according to zxcvbn.

I still have a lot to learn about information theory and I'd like to have expert input regarding entropy. Is it believed / agreed upon that entropy is an objective measure ? It seems obvious to me that it is absolutely relative and meaningless without the associated computation method / prior information.

Re: MiniLock – File encryption software that does more with less

#70

Post by selimthegrim »

higherpurpose wrote: post #64
BuildTheRobots wrote: post #61

Earlier quoted context omitted.

Depending on who you're protecting against you might want to _really_ avoid trusting your TPM.

Yeah, I wouldn't trust the TPM - certainly not from a Windows machine, and not even an Apple one after the recent revelations/research, which shows Apple tries to make the device secure against "regular" hackers, but very easy to access by Apple itself or the US government.

My current one is from atmel in 2008, before atmel quit making them, so I figure at least in this case I'm safe. I would probably not use a newer one if I was worried about TLAs though. As I am currently in the market for an MBP, where do I find this information about Apple TPMs?
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