Re: [PATCH v3 0/3] Cryptomount detached headers

[brutser]

Debian 11.4 for all the testing.

as i said, i execute shell during installation, then simply enter the commands I wrote earlier:

cryptsetup luksFormat --type luks2 -q -h sha512 -s 512 --pbkdf pbkdf2 --header /root/header.bin --luks2-metadata-size=16k --luks2-keyslots-size=512k /dev/sda2

cryptsetup luksOpen --header /root/header.bin /dev/sda2 sda2crypt

pvcreate /dev/mapper/sda2crypt

vgcreate testvg /dev/mapper/sda2crypt

lvcreate -L 2G -n root testvg

- continue install debian 11.4

- chroot into system

- copy header

- populate crypttab etc.

this whole process works 100% fine with grub 2.04 and luks1 as i said before...

> Van: Glenn Washburn <development@efficientek.com>
> Aan: brutser--- via Grub-devel <grub-devel@gnu.org>
> Onderwerp: Re: [PATCH v3 0/3] Cryptomount detached headers
> Datum: 02/08/2022 01:24:47 Europe/Paris
> Cc: brutser@perso.be;
>    dkiper@net-space.pl;
>    ps@pks.im
>
> On Tue,  2 Aug 2022 00:21:09 +0200 (CEST)
> brutser--- via Grub-devel <grub-devel@gnu.org> wrote:
>
> > Glenn,
> > 
> > 
> > 
> > Still resorted to screenshots for the debug (with the added dprintf):
> > 
> > 
> > 
> > https://imgur.com/a/YkVMdBe
>
> Ok, that confirms that the luks2 module is loaded and that the scan is
> happening. Based on the output I think luks2_read_header must be
> failing. That means that either disk reads are failing, which doesn't
> seem like the case, the disk read hook is failing or the LUKS2 magic
> bytes are not what they should be.
>
> Have you verified that after creating the volume and header file that
> cryptsetup/dm can open the volume successfully?
>
> What architecture and endianness is the machine you're running
> cryptsetup on and what is it for the one GRUB is running on?
>
> To test the read hook, add 'grub_dprintf("luks2", "read hook
> successed");' just before the last return statement in the function
> cryptodisk_read_hook in grub-core/disk/cryptodisk.c.
>
> Glenn
>
> > 
> > 
> > 
> > Van: Glenn Washburn <development@efficientek.com>
> > Aan: brutser--- via Grub-devel <grub-devel@gnu.org>
> > Onderwerp: Re: [PATCH v3 0/3] Cryptomount detached headers
> > Datum: 01/08/2022 22:50:27 Europe/Paris
> > Cc: brutser@perso.be;
> >    dkiper@net-space.pl;
> >    ps@pks.im
> > 
> > On Sat, 30 Jul 2022 11:54:32 +0200 (CEST)
> > brutser--- via Grub-devel <grub-devel@gnu.org> wrote:
> > 
> > > Glenn,
> > > 
> > > 
> > > 
> > > As I had no idea how to get the debug logs from qemu, I made screenshots, find them attached. As this is probably something I am doing wrong, I hope it shows from the logs.
> > > 
> > > https://imgur.com/a/rAlfZ77
> > 
> > Getting the output to go to serial depends on the target. For i386
> > using seabios, use "-fw_cfg name=etc/sercon-port,string=0 -serial
> > stdio".
> > 
> > Unfortunately, I'm now seeing that there are no debug log messages
> > in the luks2 module that would be shown in this case. How about putting
> > the line 'grub_dprintf("entering luks_scan");' at the start of the
> > function luks2_scan in grub-core/disk/luks2.c and then recompiling and
> > getting the output?
> > 
> > Glenn
> > 
> > 
> > > 
> > > Van: Glenn Washburn <development@efficientek.com>
> > > Aan: brutser@perso.be
> > > Onderwerp: Re: [PATCH v3 0/3] Cryptomount detached headers
> > > Datum: 29/07/2022 21:27:48 Europe/Paris
> > > Cc: grub-devel@gnu.org;
> > >    dkiper@net-space.pl;
> > >    ps@pks.im
> > > 
> > > On Fri, 29 Jul 2022 20:56:18 +0200 (CEST)
> > > brutser@perso.be wrote:
> > > 
> > > > 
> > > > testing detached header failed:
> > > > 
> > > > 
> > > > 
> > > > 1. built grub payload with following modules: ahci usb_keyboard part_msdos part_gpt at_keyboard cbfs cryptodisk luks2 lvm gcry_rijndael gcry_sha1 gcry_sha256 gcry_sha512
> > > > 
> > > > 2. encrypt a partition: cryptsetup luksFormat --type luks2 -q -h sha512 -s 512 --pbkdf pbkdf2 --header /path/to/header --luks2-metadata-size=16k --luks2-keyslots-size=512k /dev/sda1
> > > > 
> > > > (where --luks2-metadata-size=16k --luks2-keyslots-size=512k is optional, this is just to minimize header size, but I also tested without).
> > > > 
> > > > 3. from the grub cmd, i try to decrypt this partition using: cryptomount -H /path/to/header (ahci0,msdos1)
> > > > 
> > > > 
> > > > 
> > > > 4. I also tried luks1 encryption with detached header.
> > > > 
> > > > 
> > > > 
> > > > whatever I try, I always get the same error:
> > > > 
> > > > "no cryptodisk module can handle this device"
> > > > 
> > > > 
> > > > 
> > > > Is this feature not 100% implemented yet, I saw people already verifying the patches and would expect this to be working, so if yes, this seems like a bug.
> > > 
> > > This feature should be working in all cases, and if not there may be a
> > > bug. I responded to your off-list email before seeing this one. I'll
> > > repeat what I said there and let's continue this discussion on the list.
> > > 
> > > I see nothing obviously wrong with what you're doing, given the
> > > information above. To further debug this, would you be able to send a
> > > log of the serial output when the GRUB envvar debug is set to "all"
> > > while running the cryptomount command? If so, please send compressed in
> > > a reply to this email on the list.
> > > 
> > > If you can't because of hardware issues, would you be able to replicate
> > > this in QEMU and grab the serial output from there? If you can boot the
> > > system via other means, you should be able to use the raw disks (the
> > > one with the LUKS volume and the other with the filesystem containing
> > > the header file).
> > > 
> > > Glenn
> > > 
> > > 
> > > _______________________________________________
> > > Grub-devel mailing list
> > > Grub-devel@gnu.org
> > > https://lists.gnu.org/mailman/listinfo/grub-devel
> > > 
> > 
> > _______________________________________________
> > Grub-devel mailing list
> > Grub-devel@gnu.org
> > https://lists.gnu.org/mailman/listinfo/grub-devel
> > 
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel