linux-btrfs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andrei Borzenkov <arvidjaar@gmail.com>
To: Justin Brown <justin.brown@fandingo.org>, "B. S." <bs27975@gmail.com>
Cc: linux-btrfs <linux-btrfs@vger.kernel.org>
Subject: Re: Pointers to mirroring partitions (w/ encryption?) help?
Date: Sat, 4 Jun 2016 10:46:04 +0300	[thread overview]
Message-ID: <5752873C.8050105@gmail.com> (raw)
In-Reply-To: <CAKZK7uyRSUBp3J=HunPbmFVzLzzH1=QghOD2_p-5+UpyMXuGGg@mail.gmail.com>

04.06.2016 04:39, Justin Brown пишет:
> Here's some thoughts:
> 
>> Assume a CD sized (680MB) /boot
> 
> Some distros carry patches for grub that allow booting from Btrfs,
> so no separate /boot file system is required. (Fedora does not;
> Ubuntu -- and therefore probably all Debians -- does.)
> 

Which grub (or which Fedora) do you mean? btrfs support is upstream
since 2010.

There are restrictions, in particular RAID levels support (RAID5/6 are
not implemented).

>> perhaps a 200MB (?) sized EFI partition
> 
> Way bigger than necessary. It should only be 1-2MiB, and IIRC 2MiB 
> might be the max UEFI allows.
> 

You may want to review recent discussion on systemd regarding systemd
boot (a.k.a. gummiboot) which wants to have ESP mounted as /boot.

UEFI mandates support for FAT32 on ESP so max size should be whatever
max size FAT32 has.

...
> 
>> The additional problem is most articles reference FDE (Full Disk
>> Encryption) - but that doesn't seem to be prudent. e.g. Unencrypted
>> /boot. So having problems finding concise links on the topics, -FDE
>> -"Full Disk Encryption".
> 
> Yeah, when it comes to FDE, you either have to make your peace with 
> trusting the manufacturer, or you can't. If you are going to boot
> your system with a traditional boot loader, an unencrypted partition
> is mandatory.

No, it is not with grub2 that supports LUKS (and geli in *BSD world). Of
course initial grub image must be written outside of encrypted area and
readable by firmware.

> That being said, we live in a world with UEFI Secure
> Boot. While your EFI parition must be unencrypted vfat, you can sign
> the kernels (or shims), and the UEFI can be configured to only boot
> signed executables, including only those signed by your own key. Some
> distros already provide this feature, including using keys probably
> already trusted by the default keystore.
> 

UEFI Secure Boot is rather orthogonal to the question of disk encryption.


  parent reply	other threads:[~2016-06-04  7:46 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-03 20:30 Pointers to mirroring partitions (w/ encryption?) help? B. S.
2016-06-04  1:39 ` Justin Brown
2016-06-04  5:33   ` B. S.
2016-06-04  7:46   ` Andrei Borzenkov [this message]
2016-06-04 17:31     ` B. S.
2016-06-04 21:14       ` Andrei Borzenkov
2016-06-04 19:05   ` Chris Murphy
2016-06-04 21:07     ` Andrei Borzenkov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5752873C.8050105@gmail.com \
    --to=arvidjaar@gmail.com \
    --cc=bs27975@gmail.com \
    --cc=justin.brown@fandingo.org \
    --cc=linux-btrfs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).