NAME

tarsnap-keyregen - generate a key file for use with tarsnap-recrypt1

SYNOPSIS

--keyfile key-file --oldkey old-key-file --user user-name --machine machine-name [--passphrased ] [--passphrase-mem maxmem ]

DESCRIPTION

generates a set of cryptographic keys which are compatible with an existing set of cryptographic keys, registers with the tarsnap server, and writes a key file for use with tarsnap-recrypt1 and tarsnap(1). The term Qq compatible here means that it is possible to re-encrypt archives stored with the first set of keys to be stored with the second set of keys.

The --keyfile --user --machine and --oldkey parameters are all required.

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 generated on a system with far more RAM than the system on which the key file will be used.