tarsnap-keymgmt -- generate subsets of tarsnap(1) key files
tarsnap-keymgmt --outkeyfile new-key-file [-r] [-w] [-d] [--nuke] [--passphrased] [--passphrase-mem maxmem] key-file ...
tarsnap-keymgmt reads the provided key files and writes a new key file containing only the keys required for the operations specified via the -r (list and extract archives), -w (write archives), -d (delete archives), and --nuke flags. Note that -d implies -r since it is impossible to delete an individual archive without being able to read it; while a key file generated with --nuke can be used to delete all the archives stored, but not individual archives. The --recover command requires either (1) -d (archive deleting), (2) -w (archive creating), or (3) --nuke keys. The --fsck command requires either (1) both -w (archive writing) and -r (archive reading) keys, or (2) -d (archive deleting) keys. The --fsck-prune command requires -d (archive deleting) keys, since it needs to be able to delete corrupted archives. If the --passphrased option is specified, the user will be prompted to enter a passphrase (twice) to be used to encrypt the key file. If the --passphrase-mem maxmem option is specified, a maximum of maxmem bytes of RAM will be used in the scrypt key derivation function to encrypt the key file; it may be necessary to set this option if a key file is being created on a system with far more RAM than the system on which the key file will be used.