[PATCH 2/3] commands/probe: improve support of LUKS2 devices

[Pierre-Louis Bonicoli]

The --target=drive option of the probe command doesn't handle LUKS2
devices:

  # dd if=/dev/zero of=data count=10 bs=1M
  # losetup --show -f data
  /dev/loop4
  # echo -n pass | cryptsetup luksFormat -v --type luks2 /dev/loop4
  Key slot 0 created.
  Command successful.
  # echo -n pass | cryptsetup -v open /dev/loop4 test
  No usable token is available.
  Key slot 0 unlocked.
  Command successful.
  # grub-probe --device /dev/mapper/test --target=drive
  (hostdisk//dev/mapper/test)

The updated output:

  # grub-probe --device /dev/mapper/test --target=drive
  (cryptouuid/be6f4e00637148a9a40453fe9cb7f0a5)

Signed-off-by: Pierre-Louis Bonicoli <pierre-louis.bonicoli@libregerbil.fr>
---
 grub-core/osdep/devmapper/getroot.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/grub-core/osdep/devmapper/getroot.c 
b/grub-core/osdep/devmapper/getroot.c
index 9ba5c9865..96781714c 100644
--- a/grub-core/osdep/devmapper/getroot.c
+++ b/grub-core/osdep/devmapper/getroot.c
@@ -138,7 +138,8 @@ grub_util_get_dm_abstraction (const char *os_dev)
       grub_free (uuid);
       return GRUB_DEV_ABSTRACTION_LVM;
     }
-  if (strncmp (uuid, "CRYPT-LUKS1-", 12) == 0)
+  if (strncmp (uuid, "CRYPT-LUKS1-", sizeof ("CRYPT-LUKS1-") - 1) == 0
+      || strncmp (uuid, "CRYPT-LUKS2-", sizeof ("CRYPT-LUKS2-") - 1) == 0)
     {
       grub_free (uuid);
       return GRUB_DEV_ABSTRACTION_LUKS;
-- 
2.34.1