On 5/8/24 6:07 PM, Vitalii Hordii wrote:
Hello, I had some problems with restoring a luks2 partition after using, for example, mkfs.ntfs because it only leaves a 2nd JSON area without a secondary binary header, which I had to create myself. What if there was a function in libblkid that allows one to determine if there is a 2nd JSON and if there is a chance of recovery? Because as I see here, automatically repairing https://gitlab.com/cryptsetup/cryptsetup/-/issues/750 is apparently missing due to the lack of checking if there is an area here in libblkid. Also this seems to be a pretty popular problem on the internet when it comes to installing other operating systems. Would it be okay to add such a feature?
Hi, Blkid already scans for *valid* 2nd LUKS2 header. If the binary area for LUKS2 is missing, the header corrupted. Blkid should not touch JSON metadata at all (JSON on-disk follows binary area). Binary area was specifically designed for blkid use to be fast and do not require any advanced metadata parsing. So there is nothing to fix in blkid. What we can add to cryptsetup repair command is to check for specific case when wipefs marks LUKS2 binary area unusable (this case can be easily recovered as it overwrites magic string only). But I doubt mkfs format will touch only magic string, if the keyslot area is (even partially) overwritten, the LUKS2 header is unusable anyway. You should have a backup to recover data, not rely on a magic recovery. Milan
