Re: Two questions
Arno Wagner <[email protected]>
| Newsgroups | gmane.linux.kernel.device-mapper.dm-crypt |
|---|---|
| Message-ID | <[email protected]> |
On Wed, Nov 13, 2019 at 19:42:55 CET, mgreger-vDbLwGUA7lNWk0Htik3J/[email protected] wrote: > From Michael Kjörling: > > > Yes; it implies that the two volumes are encrypted using the same > master key (as well as being accessible using the same set of > passphrases), _and_ it makes it obvious that this is the case. > > (Assume any detached header is absent) > > Obvious by inspecting the raw encrypted drives? My concern is salt/iv > reuse for same sector #'s on multiple drives leading to information > leakage. > > For example let's say two encrypted drives were mirrored. Using the > same master key would make it obvious they are mirrored, but no > additional information is leaked (other than that they are in fact > copies of each other). But more complex scenarios exist: RAID, LVM2 > headers, etc. Those other scenarios are the ones I am curious about. You may also have sectors in filesystems that are generally the same and that would be obvious. The simple answer is: If you care, then do not do this. Otherwise you do not care and it is not a problem. No amount of analysis will make this go away. Regards, Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., Email: [email protected] GnuPG: ID: CB5D9718 FP: 12D6 C03B 1B30 33BB 13CF B774 E35C 5FA1 CB5D 9718 ---- A good decision is based on knowledge and not on numbers. -- Plato If it's in the news, don't worry about it. The very definition of "news" is "something that hardly ever happens." -- Bruce Schneier _______________________________________________ dm-crypt mailing list [email protected] https://www.saout.de/mailman/listinfo/dm-crypt