Qubes default cryptsetup. How strong is it?

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Setup

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Jun 21, 2016, 8:28:01 AM6/21/16
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How "quick" any of available super PCs (10,649,60 cores, 125,435. TFLOP/S ) can find the password (e.g 8-16 chars) encrypted with Qubes default settings cryptsetup?

How can we improve security to prevent this?
Is it a good idea to install some 3th party software tat dom0 to make crypto container to store some VMs and mount it before VM start?
Will Qubes Manager work fine if VMs will not be available at the boot time or some time after that, before user will not mount container?

Arqwer

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Jun 21, 2016, 5:54:02 PM6/21/16
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Will Qubes Manager work fine if VMs will not be available at the boot time or some time after that, before user will not mount container?
 
Yes. I have R3.0, and some vm's are on secondaty, encrypted drive. I mount it using crontab like
@reboot /my/script/to/mount/encrypted/secondary/drive
I used this instruction to move appvms there. But I did it not in purpose of security, but just to have more disk space. I store the key to that drive in dom0.


How "quick" any of available super PCs (10,649,60 cores, 125,435. TFLOP/S )  can find the password (e.g 8-16 chars) encrypted with Qubes default settings cryptsetup?

Encryption is the hardest part of chain. If the passphrase is long enough.If password is 16 random lowercase and uppercasr letters, then it is  52^16 combinations, it is about 10^27. If you can crack 100 Peta passwords/S, then it will take 10^(27-17) = 10^(10) seconds to brute the password, which is 316 years. (Really expectation is half of it, so 158 years on average). Of course, if those letters are not "Password12345678".

How can we improve security to prevent this?

If 316 years is not enough, than you can add one more character, to make it  16 thousands of years!

Is it a good idea to install some 3th party software tat dom0 to make crypto container to store some VMs and mount it before VM start?

I don't think so. The more different tools you use, the more there are chances to use something wrong.

After all, there are much easier ways to get your data.  For example hardware backdoor called Intel ME.

Robin Schneider

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Jun 21, 2016, 6:16:17 PM6/21/16
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Hash: SHA512

On 21.06.2016 23:54, Arqwer wrote:
> How "quick" any of available super PCs (10,649,60 cores, 125,435. TFLOP/S
>> ) can find the password (e.g 8-16 chars) encrypted with Qubes default
>> settings cryptsetup?
>>
>
> Encryption is the hardest part of chain. If the passphrase is long
> enough.If password is 16 random lowercase and uppercasr letters, then it
> is 52^16 combinations, it is about 10^27. If you can crack 100 Peta
> passwords/S, then it will take 10^(27-17) = 10^(10) seconds to brute the
> password, which is 316 years. (Really expectation is half of it, so 158
> years on average). Of course, if those letters are not "Password12345678".
>
> How can we improve security to prevent this?
>
>
> If 316 years is not enough, than you can add one more character, to make
> it 16 thousands of years!


Most of those projections about how many years brute forcing a passphrase with
that many bits of entropy may take completely ignore one key aspect, especially
when you are talking about hundreds of years and that is technical advance and
Moore's law. So to be realistic, you would need to take that into
consideration.

Refer to:

*
https://crypto.stackexchange.com/questions/1815/how-to-account-for-moores-law-in
- -estimating-time-to-crack

- --
Live long and prosper
Robin `ypid` Schneider
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Andrew David Wong

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Jun 21, 2016, 10:51:22 PM6/21/16
to Robin Schneider, qubes...@googlegroups.com
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

On 2016-06-21 15:16, Robin Schneider wrote:
> On 21.06.2016 23:54, Arqwer wrote:
>> How "quick" any of available super PCs (10,649,60 cores,
>> 125,435. TFLOP/S
>>> ) can find the password (e.g 8-16 chars) encrypted with Qubes
>>> default settings cryptsetup?
>>>
>
>> Encryption is the hardest part of chain. If the passphrase is
>> long enough.If password is 16 random lowercase and uppercasr
>> letters, then it is 52^16 combinations, it is about 10^27. If
>> you can crack 100 Peta passwords/S, then it will take 10^(27-17)
>> = 10^(10) seconds to brute the password, which is 316 years.
>> (Really expectation is half of it, so 158 years on average). Of
>> course, if those letters are not "Password12345678".
>
>> How can we improve security to prevent this?
>
>
>> If 316 years is not enough, than you can add one more character,
>> to make it 16 thousands of years!
>
>
> Most of those projections about how many years brute forcing a
> passphrase with that many bits of entropy may take completely
> ignore one key aspect, especially when you are talking about
> hundreds of years and that is technical advance and Moore's law.
> So to be realistic, you would need to take that into
> consideration.
>
> Refer to:
>
> * https://crypto.stackexchange.com/questions/1815/how-to-account-
> for-moores-law-in-estimating-time-to-crack
>

True, but there may also be thermodynamic limitations. As Schneier
wrote in _Applied Cryptography_:

"These numbers have nothing to do with the technology of the devices;
they are the maximums that thermodynamics will allow. And they
strongly imply that brute-force attacks against 256-bit keys will be
infeasible until computers are built from something other than matter
and occupy something other than space."

- --
Andrew David Wong (Axon)
Community Manager, Qubes OS
https://www.qubes-os.org
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