Using vnd as keydisk for bioctl?

[CiotBSD]

Hi.
Is it possible to use a vnd(4) as a keydisk for bioctl(8)?
(crypted disk mount on /mnt/xyz correctly with one keydisk)

My attempt:

$ doas dd if=/dev/zero of=disk.img bs=1g count=1

$ doas vnconfig disk.img 
vnd0

$ doas disklabel -E /dev/vnd0c
Label editor (enter '?' for help at any prompt)
/dev/vnd0c> p g
OpenBSD area: 0-2097152; size: 1.0G; free: 1.0G
#                size           offset  fstype [fsize bsize   cpg]
  c:             1.0G                0  unused                    
/dev/vnd0c> a a
offset: [0] 
size: [2097152] 
FS type: [4.2BSD] RAID
/dev/vnd0c*> w
/dev/vnd0c> q
No label changes.

$ doas dd bs=8192 seek=1 if=bckp.k.img of=/dev/rvnd0a                                                                                                     
110914+0 records in
110914+0 records out
908607488 bytes transferred in 80.264 secs (11320180 bytes/sec)

$ doas bioctl -c C -k vnd0a -l 892fc22d89c0ff24.a softraid0
Nov 14 14:43:48 srvr /bsd: softraid0: vnd0a is not a key disk

error of reasoning or really not possible?

[jggimi]

I am able to use a vnd(4) device as a bioctl(8) keydisk, as follows:

• Create the backing store with vmctl(8)
• Create the disklabel partition, type RAID
• Name the partition in a bioctl(8) -c C command as a -k option.

I did not attempt to overlay any data in the key device.

Edited to add my example:

# vmctl create -s 1g /tmp/key.disk
vmctl: raw imagefile created
# vmctl create -s 5g /tmp/encrypt.disk
vmctl: raw imagefile created
# vnconfig vnd0 /tmp/key.disk
# vnconfig vnd1 /tmp/encrypt.disk
# disklabel -E vnd0
Label editor (enter '?' for help at any prompt)
vnd0> a a
offset: [0]
size: [2097152]
FS type: [4.2BSD] raid
vnd0*> w
vnd0> q
No label changes.
# disklabel -E vnd1
Label editor (enter '?' for help at any prompt)
vnd1> a a
offset: [0]
size: [10485760]
FS type: [4.2BSD] raid
vnd1*> w
vnd1> q
No label changes.
# bioctl -c C -k /dev/vnd0a -l /dev/vnd1a softraid0
softraid0: CRYPTO volume attached as sd2
#

[CiotBSD]

vmctl? plz, explain.

[jggimi]

The vmctl(8) command used to manage hypervisor guests has a "create" option which creates sparse files.

I have added my console output to my response above, where you can see I used the vmctl(8) command to create the backing storage for a 1 GB key disk and a 5 GB encrypted disk.

[CiotBSD]

Ok, In your example, you initiate softraid with the virtual disk, created by vmctl. I understand.
(egual process than using dd)

But, in the use case, where the softraid was created with a keydisk, and backuped.
How can I use the backup as virtual disk?

[jggimi]

I just tested backup and recovery of the key partition using dd(1). Works fine. To keep it manageable I used a small, 5MB key disk.

# # create disks:
# vmctl create -s 5m /tmp/key.disk
vmctl: raw imagefile created
# vmctl create -s 5g /tmp/encrypted.disk
vmctl: raw imagefile created
# vnconfig vnd0 /tmp/key.disk
# vnconfig vnd1 /tmp/encrypted.disk
# disklabel -E vnd0
Label editor (enter '?' for help at any prompt)
vnd0> a a
offset: [0]
size: [10240]
FS type: [4.2BSD] raid
vnd0*> w
vnd0> q
No label changes.
# disklabel -E vnd1
Label editor (enter '?' for help at any prompt)
vnd1> a a
offset: [0]
size: [10485760]
FS type: [4.2BSD] raid
vnd1*> w
vnd1> q
No label changes.
# # create softraid disk:
# bioctl -c C -k /dev/vnd0a -l /dev/vnd1a softraid0
softraid0: CRYPTO volume attached as sd2
# disklabel -E sd2
Label editor (enter '?' for help at any prompt)
sd2> a a
offset: [0]
size: [10485232]
FS type: [4.2BSD]
sd2*> w
sd2> q
No label changes.
# newfs sd2a
/dev/rsd2a: 5119.7MB in 10485216 sectors of 512 bytes
26 cylinder groups of 202.50MB, 12960 blocks, 25920 inodes each
super-block backups (for fsck -b #) at:
 160, 414880, 829600, 1244320, 1659040, 2073760, 2488480, 2903200, 3317920, 3732640, 4147360, 4562080, 4976800,
 5391520, 5806240, 6220960, 6635680, 7050400, 7465120, 7879840, 8294560, 8709280, 9124000, 9538720, 9953440,
 10368160,
# mount /dev/sd2a /mnt
# echo this is a test file > /mnt/test.file
# umount /mnt
# # detach softraid drive and back up key disk:
# bioctl -d sd2
# dd if=/dev/rvnd0a of=/tmp/key.disk.dd.backup
10240+0 records in
10240+0 records out
5242880 bytes transferred in 0.342 secs (15329018 bytes/sec)
# # test recovery with a new key drive:
# vmctl create -s 5m /tmp/new.key.disk
vmctl: raw imagefile created
# vnconfig vnd2 /tmp/new.key.disk
# disklabel -E vnd2ke
Label editor (enter '?' for help at any prompt)
vnd2> a a
offset: [0]
size: [10240]
FS type: [4.2BSD] raid
vnd2*> w
vnd2> q
No label changes.
# dd if=/tmp/key.disk.dd.backup of=/dev/rvnd2a
10240+0 records in
10240+0 records out
5242880 bytes transferred in 4.678 secs (1120655 bytes/sec)
# bioctl -c C -k /dev/vnd2a -l /dev/vnd1a softraid0
softraid0: CRYPTO volume attached as sd2
# mount /dev/sd2a /mnt
# cat /mnt/test.file
this is a test file
#

[CiotBSD]

@jggimi: thanks.
But, I dont known why, this not runs on my use case. (perhaps, it's due to I use crypted HD).

[jggimi]

Please note that my backup and restore were of the keydisk partition (backup from: /dev/rvnd0a, restore to: /dev/rvnd2a), only, and were not of the entire drive.