Using DMCrypt to create, create an encrypted filesystem, mappable and mountable filesystem and mount same.
Using DMCrypt to create an encrypted partition on your thumbdrive.
Remove all partitions from the current ThumbDrive:
parted -s ‘rm 1’ DEVICE
Find partitionable size:
~$ sudo fdisk -l /dev/sdc | grep bytes | head -1 | sed ‘s/^.* \(*\) bytes/\1 \/ 1000000/’ | bc
Partition the ThumbDrive:
parted -s ‘mkpart primary 0 16039’ DEVICE
Create the DeviceMapper device:
sudo cryptsetup create NAME DEVICE
Make a filesystem on the mapped device (non-journaled FS’s only):
Mount the filesystem where appropriate:
mount /dev/mapper/NAME /map-point