Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Adaptive padding rebased 0.3.6 pr547 squashed fixups #573

Conversation

asn-d6
Copy link
Member

@asn-d6 asn-d6 commented Dec 7, 2018

No description provided.

Mike Perry and others added 30 commits November 30, 2018 23:44
We need this for padding negotiation so that we can have later machine
revisions supercede earlier ones.
This is a good code review start point, to get an overview of the interfaces
and types used in circuit padding.
This helps us to determine if a middle node can pad to us or not.
These event callbacks allow circuit padding to decide when to attempt to
launch and negotiate new padding machines, and when to tear old ones down.
These callbacks allow the padding state machines to react to various types of
sent and received relay cells.
This implements all of the event handling, state machines, and padding
decisions for circuit padding.

I recommend reviewing this after you look at the call-in points into it from
the rest of Tor.
* Tighten and justify cutoff for approximation in GPD sampler.
* Use expm1(-xi log U) to evaluate U^{-xi} - 1 without precision loss.
* Use log1p(x) to evaluate log(1 + x) precisely even for x near 0.
* Avoid 0 by rejection sampling, not by choosing to return 0 instead.
  (This avoids the problematic 0 return from crypto_rand_double()
   into the log() without introducing distribution bias).
Hope is this will make it easier to test on the live tor network.

Does not need to be merged if we don't want to, but will come in handy
for researchers.
Note to self/others: don't merge this.
This project introduces the prob_distr.c subsystem which implements all the
probability distributions that WTF-PAD needs. It also adds unittests for all of
them.

Code and tests courtesy of Riastradh.

Co-authored-by: Taylor R Campbell <campbell+tor@mumble.net>
Also add some basic tests for sampling delays from the uniform distribution.
Tighten up integer-like type usage.
Tighten up integer type usage.
Tighten up type usage.
@asn-d6 asn-d6 closed this Dec 10, 2018
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
1 participant