CS3753 (Operating Systems)
Spring 2012
University of Colorado Boulder
Programming Assignment 5
A FUSE Encrypted File System
Public Code

By Andy Sayler - 2012
<www.andysayler.com>

Inspired by work from Chris Wailes - 2010
<chris.wailes@gmail.com>

With help from:
Junho Ahn - 2012

Various files adopted from other exiting work.
See file comments for specific details and references.

---Dependencies---
fuse-utils
openssl
attr
attr-dev
libfuse-dev
libssl1.0.0 or libssl0.9.8
libssl-dev

Note: To use extended attributes (xattr) on EXT filesystems,
      you must add the 'user_xattr' mount option to the
      mount options of any mounts on which you intend to use 
      extended attributes. Failure to so may result in an error
      when trying to set, get, or remove xattr values.

---Folders---
handout - Assignment description and documentation

---Files---
Makefile         - GNU makefile to build all relevant code
README           - This file
fusehello.c      - Basic "Hello World" FUSE example
fusexmp.c        - Basic FUSE mirrored filesystem example (mirrors /)
xattr-util.c     - Basic Extended Attribute manipulation program
aes-crypt-util.c - Basic AES encryption program using aes-crypt library
aes-crypt.h      - Basic AES file encryption library interface
aes-crypt.c      - Basic AES file encryption library implementation

---Executables---
fusehello      - Mounting executable for "Hello World" FUSE filesystem example
fusexmp        - Mounting executable for root (\) mirror FUSE filesystem example
xattr-util     - A simple program for manipulating extended attributes
aes-crypt-util - A simple program for encrypting, decrypting, or copying files

---Documentation---
handout/pa5.pdf             - Assignment Instructions and Tips
http://youtu.be/VrMi6RaUNDs - Assignment Explanation Video 1

---Examples---

***Building***

Build All:
 make

Build Fuse Examples and Utilities:
 make fuse-examples

Build xattr Examples and Utilities:
 make xattr-examples

Build OpenSSL/AES Examples and Utilities:
 make openssl-examples

Clean:
 make clean

***FUSE Examples***

Mount fusehello on new directory
 mkdir <Mount Point>
 ./fusehello <Mount Point>

Mount fusehello in Debug Mode on existing empty directory
 ./fusehello -d <Mount Point>

Mount fusexmp on existing directory and list (ls) mirrored root directory (/)
 ./fusexmp <passphrase> <mirror directory> <Mount Point>
 ls <Mount Point>

Unmount a FUSE filesystem
 fusermount -u <Mount Point>

***OpenSSL Examples***

Copy FileA to FileB:
 ./aes-crypt-util -c <FileA Path> <FileB Path>

Encrypt FileA to FileB using Passphrase:
 ./aes-crypt-util -e <Passphrase> <FileA Path> <FileB Path>

Decrypt FileA to FileB using Passphrase:
(Note: error if FileA not encrypted with aes-crypt.h or if passphrase is wrong)
 ./aes-crypt-util -d <Passphrase> <FileA Path> <FileB Path>

***xattr Examples***

List attributes set on a file
 ./xattr-util -l <File Path>

Set/Write attribute on a file
 ./xattr-util -s <Attr Name> <Attr Value> <File Path>

Get/Read attribute from a file
 ./xattr-util -g <Attr Name> <File Path>

Remove attribute from a file
 ./xattr-util -r <Attr Name> <File Path>