Archives/obfs4
2
0
Fork 0
mirror of https://gitlab.com/yawning/obfs4.git synced 2024-11-15 12:12:53 +00:00
Code Issues Projects Releases Wiki Activity
The obfourscator (obfs4proxy)
51 Commits 1 Branch 14 Tags 502 KiB
Go 100%
8d61c6bcc6
Go to file
Yawning Angel 8d61c6bcc6 Use the new goptlib goodies. 
As of `15b960d55905877a840fe605a41a8139bffb5329` goptlib supports
IsClient, IsServer, and handling the StateLocation.

Yes this means you need to use goptlib out of git.
2014-05-21 09:38:37 +00:00
doc Change the MSS to 1448 bytes, because timestamps are a thing. 2014-05-21 01:45:17 +00:00
framing Change the MSS to 1448 bytes, because timestamps are a thing. 2014-05-21 01:45:17 +00:00
ntor Change the handshake wire format. 2014-05-16 00:11:53 +00:00
obfs4proxy Use the new goptlib goodies. 2014-05-21 09:38:37 +00:00
.gitignore Move to a unified client/server binary, and fix bugs. 2014-05-12 00:02:24 +00:00
handshake_ntor_test.go Initial import. 2014-05-09 10:23:58 +00:00
handshake_ntor.go Finish adding godoc comments to all public interfaces. 2014-05-21 00:26:25 +00:00
obfs4.go Finish adding godoc comments to all public interfaces. 2014-05-21 00:26:25 +00:00
packet.go Send the DRBG seed as a packetTypePrngSeed post server handshake. 2014-05-15 20:21:46 +00:00
README.md Update README (No functional changes). 2014-05-16 05:06:38 +00:00
utils.go Add vim modelines to some files (No functional changes). 2014-05-13 09:56:25 +00:00
weighted_dist.go Change the server failure close delay/discard length to be consistent. 2014-05-18 03:37:22 +00:00

README.md

obfs4 - The obfourscator

Yawning Angel (yawning at torproject dot org)

WARNING

This is pre-alpha. Don't expect any security or wire protocol stability yet. If you want to use something like this, you should currently probably be looking at ScrambleSuit.

What?

This is a look-like nothing obfuscation protocol that incorporates ideas and concepts from Philipp Winter's ScrambleSuit protocol. The obfs naming was chosen primarily because it was shorter, in terms of protocol ancestery obfs4 is much closer to ScrambleSuit than obfs2/obfs3.

The notable differences between ScrambleSuit and obfs4:

  • The handshake always does a full key exchange (no such thing as a Session Ticket Handshake).
  • The handshake uses the Tor Project's ntor handshake with public keys obfuscated via the Elligator 2 mapping.
  • The link layer encryption uses NaCl secret boxes (Poly1305/XSalsa20).

Why not extend ScrambleSuit?

It's my protocol and I'll obfuscate if I want to.

Since a lot of the changes are to the handshaking process, it didn't make sense to extend ScrambleSuit as writing a server implementation that supported both handshake variants without being obscenely slow is non-trivial.

TODO

  • Code cleanups.
  • Write more unit tests.
  • Optimize further.

WON'T DO

  • I do not care that much about standalone mode. Patches MAY be accepted, especially if they are clean and are useful to Tor users.
  • Yes, I use a bunch of code from the borg^w^wGoogle. If that bothers you feel free to write your own implementation.
  • I do not care about older versions of the go runtime.

Thanks

  • David Fifield for goptlib.
  • Adam Langley for his Elligator implementation.
  • Philipp Winter for the ScrambleSuit protocol which provided much of the design.