Encrypted USB
From charlesreid1
Changing Encryption Passphrase on Encrypted USB Drive
http://www.cyberciti.biz/hardware/howto-linux-hard-disk-encryption-with-luks-cryptsetup-command/ - changing the encryption passphrase on an encrypted USB drive
Print some info:
$ fdisk -l $ cryptsetup luksDump /dev/sdc1
Add the new encryption key:
$ cryptsetup luksAddKey /dev/sdc1
Enter your old passphrase, then your new passphrase twice.
Now delete your old passphrase:
$ cryptsetup luksRemoveKey /dev/sdc1
Enter the old passphrase to be deleted.