Re: Beheaded LUKS volume pathology

On 2/2/24 11:16, Milan Broz wrote:

> So if the user does not deliberately write some information elsewhere
> (like pair detached header and data device using storage UUID
> in /etc/crypttab), there should be no information that logically connects
> the detached LUKS header and data device (for default config).
> 

Hello,

So, just to confirm, there is no metadata present in the LUKS header 
that would allow an adversary to perform guesswork (such as the size of 
the encrypted volume)?

For example, if I have a bunch of encrypted disks with detached headers, 
and only one of them is 10TB, but the rest are 1TB. You're saying 
there's no way that a particular header can be singled out based on 
guesswork because it's the only header that has a bigger encrypted 
volume body?

How does an encrypted volume know what size it's supposed to be? Does it 
always span across the entire partition or block device?


Kind regards!
M.