On Thu, Nov 6, 2008 at 10:27 AM, Xavier Nicollet <[EMAIL PROTECTED]> wrote: > Le 06 novembre 2008 à 09:58, Gregory Maxwell a écrit: >> The latter would need to be a probably need to be a secret-keyed HMAC >> to prevent watermarking attacks and information leakage, [...] > > Dm-crypt on every disks seems a good alternative, doesn't it ? > You would use dm-crypt for your swap anyway. > > Did I miss something ?
Dmcrypt is fine but a rather blunt tool: It's all or nothing, and only a single key. It also can not store a unique nonce per block update, which may create some (theoretical) security weaknesses. The whole thing will need to be mounted with keys in memory even when you only care about a few files. (so someone who gains access to the system could access high security files even if the system was just being used for web-browsing at the time) With a more intelligent you could have per-subvolume keying, or even better per-file allowing the encrypted filesystem to contain a mix of files with differing security classes. Take a look at http://ecryptfs.sourceforge.net/ for an example of a more-sophisticated filesystem encryption feature set. At the least I think it would be useful if btrfs provided dmcrypt functionality per subvolume, though full ecryptfs level functionality would be quite interesting. N�����r��y����b�X��ǧv�^�){.n�+����{�n�߲)����w* jg��� �����ݢj/���z�ޖ��2�ޙ����&�)ߡ�a���� �G���h��j:+v���w��٥
