Without explaining exactly how this is generated, it can be confusing
and worrying to not know how the password that encrypts your data is
stored.
This also brings peace of mind to the user that even though
the same password is obscured differently each time, all the data to
get back to the original password remains. Explaining how it works
is much better than the reader of the documentation having to trust
a blackboxy/magical mechanism.
This is a simple "rotate" of the filename, with each file having a rot
distance based on the filename. We store the distance at the beginning
of the filename. So a file called "go" would become "37.KS".
This is not a strong encryption of filenames, but it should stop automated
scanning tools from picking up on filename patterns. As such it's an
intermediate between "off" and "standard". The advantage is that it
allows for longer path segment names.
We use the nameKey as an additional input to calculate the obfuscation
distance. This should mean that two different passwords will result
in two different keys
The obfuscation rotation works by splitting the ranges up and handle cases
0-9
A-Za-z
0xA0-0xFF
and anything greater in blocks of 256
