PlayBack

Warning: This is alpha-level software, not ready for anyone to use it. If you're adventurous, you can try it, but please make sure:

1. That there are no sensitive files containing account data or something similar on your console
2. That you run the server under a user with minimal access to anything/in a vm/in a container, so that attackers that may be able to override files won't do much harm

Description

You should regularly make backups. For Everything. But for hacked consoles it isn't always that easy. In lots of cases (Vita, Original XBox, PS2), their files are basically only available via FTP, which can be slow and has to be driven by a computer. PlayBack is a portable backup , which can backup your device to a server. Depending on the client, device-encrypted files may even be transparently decrypted, so you can continue playing on a seperate console.

Available Clients:

• Client C library for most of the logic
• Linux client as a reference
• Vita client
• 3DS client

Available Servers:

• Reference server, Rust based (Unix, may have serious path traversal bugs on Windows or similar things)

It works over a encrypted TCP connection to Port 9483. Your encryption key is the authentication of your client & server, but if you're on an untrustworthy network with people who can guess that key, all your files can be leaked. You can only change or upload new files to the server, not read existing ones.

Client config

# Comments are done with a leading '#' followed by a space

# hostname or ip of the server
server localhost
# name of the device, done for identification
name test
# the encryption key, used for authentication & encryption
# use something reasonably long (> 15 characters) & random
key hunter2
# the directorie(s) to synchronise
dir fat:/apps/
dir fat:/wbfs/
# ignore pattern(s) for files that shouldn't be synced to the server
ignore tmp$
# update pattern(s) for files that might change without the modification time
# changing as well
update sav$
update save$

The regex engine understands the following elements: '.', '*', '+', '?', '^', '$'

Location

• On 3ds the config file has to be at "sdmc:/plybck.cfg"
• On vita the config file has to be at "ux0:/data/plybck.cfg"

Q&A

1. The syncs are always really slow! How can that be?

   On every sync, a list of all your files and folders will be transmitted. This may take a few minutes.

   If you have a directory with lots of files on the 3ds, certain operations slow down significantly. This seems to be an inherent limitation of the 3ds.

2. The initial sync is really slow, can't you speed it up?

   Most game consoles seem to have very slow network interfaces. You may try to copy all the files manually another way, so the first sync doesn't have to send all the files

3. Why doesn't it work on Windows?

   Because secure path handling & conserving encoding seem to be really hard on Windows and I don't use/care about Windows. You're welcome to open a PR. Maybe just use a Raspberry Pi for the always-on server.

4. Why not just use FTP/rsync/webdav/syncthing/...?

   Because they either require a lot of client state, which for some consoles like the DS, with only 4MB of ram, may not be feasible or are undocumented. Here the client state is mostly limited to the file that is currently synced.

5. Why no 2-way sync? Only paths with 256 characters? Is this the 90s?

   Maybe in the future

6. My favourite console, the Game.com, isn't supported. What should I do?

   I'll try to implement support for some more common consoles, but if you don't want to wait, try implementing it yourself.

7. So where do I get the encryption from? Should I just use my email password?

   No, don't use anything you can remember. Just generate a random key. If you have no idea how to do that, use this. Ideally it should be more than 64 Characters long.

8. Is it safe to interrupt the sync process?

   Yes. It may leave the file that is currently being transmitted incomplete, but it will be retransmitted on the next sync.

Based on

• Clientlib
  • PKGJ for the config parser by Philippe Daouadi (BSD 2-Clause)
  • Murmur3 for file hash by Austin Appleby from qLibc ported by Seungyoung Kim (BSD 2-Clause)
  • Tweetnacl for cryptographic functions by djb and others (public domain)
  • Regex based on the 30 line implementation by Rob Pike (probably public domain?)
• Vita client
  • Vitasdk by vitasdk (MIT/GPLv3)
• 3ds client
  • libctru by Smealum (MIT)
• Server
  • Rust, so I'm reasonably sure it doesn't have RCE Bugs
  • Crates:
    • Log by The Rust Project Developers (MIT/Apache-2.0)
    • Simplelog by Victor Brekenfeld (MIT/Apache-2.0)
    • Failure by Without Boats (MIT/Apache-2.0)
    • Structopt by Guillaume Pinot (MIT/Apache-2.0)
    • Murmur3 by Stu Small (MIT/Apache-2.0)
    • Byteorder by Andrew Gallant (Unlicense/MIT)
    • Filetime by Alex Crichton (MIT/Apache-2.0)
    • Toml by Alex Crichton (MIT/Apache-2.0)
    • Serve by David Tolnay & Erick Tryzelaar (MIT/Apache-2.0)
    • Sodiumoxide by Daniel Ashhami & Frank Denis (MIT/Apache-2.0)

License

Everything is licensed under AGPL, found in the LICENSE file, except files with their own copyright header.

The client library may be relicensed when the need arises, for example a GPLv2 or proprietary sdk. Please be aware of that when creating pull requests.

Known Issues

• The 3DS client takes really long for directories with lots of files. This seems to be an inherent limitation of the 3ds.
• The 3DS client handling of the home menu/power menu still has some issues