Other FreeBSD and VeraCrypt data (GPT GUID 8c8f8eff-ac95-4770-814a-21994f2dbc8f, partition type code E900)

grahamperrin

Son of Beastie

Reaction score: 835
Messages: 2,687

Background

Users of VeraCrypt are strongly discouraged from using an entire device:

1630285582493.png

Also, there's encouragement to use FAT (not UFS) for the file system.

User experience (UX)

If an ms-basic-data GPT partition (type code 0700, Microsoft basic data) is available, then VeraCrypt can not select the partition.

If a freebsd-ufs GPT partition (type code A503, FreeBSD UFS) is available, then VeraCrypt can not select the partition. Adding a UFS file system to the FreeBSD UFS partition seems to make no difference.

GPT partition type code E900Veracrypt data – seems to be not recognised by FreeBSD utilities such as gpart(8).

Below: VeraCrypt can select a fat32lba partition of a disk that uses MBR (not a GUID partition table).

2021-08-30 01:33:11 da4p1 not listed.png2021-08-30 01:35:26 two for one.png2021-08-30 01:40:10 still no da4p1.png

FreeBSD bug 258157 – GPT: recognise GUID 8c8f8eff-ac95-4770-814a-21994f2dbc8f (partition type code E900) as VeraCrypt data

Code:
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: ugen0.6: <General UDisk> at usbus0
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: umass1 on uhub6
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: umass1: <General UDisk, class 0/0, rev 2.00/1.00, addr 26> on usbus0
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: da4 at umass-sim1 bus 1 scbus5 target 0 lun 0
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: da4: <General UDisk 5.00> Removable Direct Access SCSI-2 device
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: da4: 40.000MB/s transfers
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: da4: 1901MB (3893248 512 byte sectors)
Aug 30 01:30:11 mowa219-gjp4-8570p-freebsd kernel: da4: quirks=0x2<NO_6_BYTE>
^C
root@mowa219-gjp4-8570p-freebsd:~ # gdisk /dev/da4
GPT fdisk (gdisk) version 1.0.8

Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present

Found valid GPT with protective MBR; using GPT.

Command (? for help): p
Disk /dev/da4: 3893248 sectors, 1.9 GiB
Sector size (logical): 512 bytes
Disk identifier (GUID): 3AD83790-460F-41E3-8AE1-B35570BF2E21
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 3893214
Partitions will be aligned on 2048-sector boundaries
Total free space is 2014 sectors (1007.0 KiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048         3893214   1.9 GiB     E900  Veracrypt data

Command (? for help): q
root@mowa219-gjp4-8570p-freebsd:~ # gpart show da4
=>     34  3893181  da4  GPT  (1.9G)
       34     2014       - free -  (1.0M)
     2048  3891167    1  !8c8f8eff-ac95-4770-814a-21994f2dbc8f  (1.9G)

root@mowa219-gjp4-8570p-freebsd:~ # tail -f -n 0 /var/log/messages
Aug 30 01:34:49 mowa219-gjp4-8570p-freebsd kernel: ugen0.6: <General UDisk> at usbus0 (disconnected)
Aug 30 01:34:49 mowa219-gjp4-8570p-freebsd kernel: umass1: at uhub6, port 2, addr 26 (disconnected)
Aug 30 01:34:49 mowa219-gjp4-8570p-freebsd kernel: da4 at umass-sim1 bus 1 scbus5 target 0 lun 0
Aug 30 01:34:49 mowa219-gjp4-8570p-freebsd kernel: da4: <General UDisk 5.00>  detached
Aug 30 01:34:49 mowa219-gjp4-8570p-freebsd kernel: (da4:umass-sim1:1:0:0): Periph destroyed
Aug 30 01:34:49 mowa219-gjp4-8570p-freebsd kernel: umass1: detached
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: ugen0.6: <General UDisk> at usbus0
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: umass1 on uhub6
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: umass1: <General UDisk, class 0/0, rev 2.00/1.00, addr 27> on usbus0
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: da4 at umass-sim1 bus 1 scbus5 target 0 lun 0
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: da4: <General UDisk 5.00> Removable Direct Access SCSI-2 device
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: da4: 40.000MB/s transfers
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: da4: 1901MB (3893248 512 byte sectors)
Aug 30 01:34:51 mowa219-gjp4-8570p-freebsd kernel: da4: quirks=0x2<NO_6_BYTE>
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: ugen0.12: <General UDisk> at usbus0
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: umass5 on uhub6
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: umass5: <General UDisk, class 0/0, rev 2.00/1.00, addr 28> on usbus0
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: da8 at umass-sim5 bus 5 scbus9 target 0 lun 0
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: da8: <General UDisk 5.00> Removable Direct Access SCSI-2 device
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: da8: 40.000MB/s transfers
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: da8: 1911MB (3913728 512 byte sectors)
Aug 30 01:35:16 mowa219-gjp4-8570p-freebsd kernel: da8: quirks=0x2<NO_6_BYTE>
^C
root@mowa219-gjp4-8570p-freebsd:~ # mount | grep -i vera
root@mowa219-gjp4-8570p-freebsd:~ # mount | grep -i General
/dev/da4p1 on /media/General_UDisk__p1 (msdosfs, local)
root@mowa219-gjp4-8570p-freebsd:~ # gpart show da4 da8
=>     34  3893181  da4  GPT  (1.9G)
       34     2014       - free -  (1.0M)
     2048  3891167    1  !8c8f8eff-ac95-4770-814a-21994f2dbc8f  (1.9G)

=>     63  3913665  da8  MBR  (1.9G)
       63     1985       - free -  (993K)
     2048  3911680    1  fat32lba  [active]  (1.9G)

root@mowa219-gjp4-8570p-freebsd:~ #
 
OP
grahamperrin

grahamperrin

Son of Beastie

Reaction score: 835
Messages: 2,687

Workaround for GPT partitions that are non-selectable in the VeraCrypt application

Ignore the invisibility. Don't try to select what's not visible.

Instead, type the path to the partition.

Encryption of the partition can be followed by a change to its type.

An example:
  1. /dev/da8p1 was originally freebsd-swap (type code A502, FreeBSD swap)
  2. VeraCrypt encrypted the partition with a UFS file system
  3. GPT fdisk – sysutils/gdisk | gdisk(8) – made it a VeraCrypt data partition (instead of FreeBSD swap)
  4. in the VeraCrypt window (pictured below), I typed /dev/da8p1 then clicked Mount
1630289485017.png
 
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