UtahFS
UtahFS is a state-of-the art encrypted storage solution, meant to be similar to
Dropbox. It has a FUSE binding that creates a synthetic drive on the user's
computer that they can interact with like an external hard-drive. Files stored
in the drive are uploaded to a cloud storage provider, which means the drive
will never run out of space and minimizes the likelihood of any files being
lost. However the files are encrypted such that the cloud storage provider knows
almost nothing about what's being stored.
Features
- Interchangeable Storage Providers. For storing data in the cloud, UtahFS
uses Object Storage, which is cheap and commodified. Example providers
include: AWS S3, Google Cloud Storage, Backblaze B2, and Wasabi. - Very Very Strong Encryption. The method of encryption hides the number of
files, file names, file contents, individual file size, and prevents any
modifications (including rollbacks!). The only information which is clearly
leaked is the maximum archive size: archives grow to fit new data, but won't
shrink if that data is deleted. Instead, that space is left allocated and
will be re-used if needed in the future. - Local Hardware allows Multiple Users and Improved Performance. If the
user has server-like hardware on their LAN (Rasberry Pi / Intel NUC), this
can be used to coordinate multiple users operating in the same archive. It
can also dramatically improve the performance of uploads, because a user can
upload large amounts of already-encrypted data to the server over the fast
local network, and let the server take over the much slower upload to the
cloud provider. - Archive Mode. The client can be configured to guard against deleting or
overwriting existing files, while still allowing new files to be created and
old files to be moved around. This helps protect against accidental data
loss. - Oblivious RAM (ORAM). ORAM can be used to hide the access pattern of
data from the cloud storage provider, so the provider only sees the amount
data is accessed. (Access pattern: Which pieces of data are being accessed,
and whether the access was a read or write.)
How to Use
Setup documentation can be found in the docs/ folder.
Future Work
- Reliability strategies for the WAL. Changes are buffered in a local
Write-Ahead Log (WAL) before being sent to the cloud storage provider. If the
disk that the WAL is stored on fails, it could become very difficult to
return the archive to a usable, partially-regressed state.