Reported on tor-dev by Gisle Vanem. Bug not in any released Tor
(The suggested patch used _MSC_VER, but that's not how we do stuff
with autoconf. With autoconf, you detect the feature you want,
rather than trying to list all the systems that do or do not have
it.)
In theory it would be better to detect this bug in advance, but this
approach is much simpler, and therefore safer to backport.
This closes tor issue 28973.
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>
Co-authored-by: Mike Perry <mikeperry-git@torproject.org>
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.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
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.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
These callbacks allow the padding state machines to react to various types of
sent and received relay cells.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
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.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
This is a good code review start point, to get an overview of the interfaces
and types used in circuit padding.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
We need this for padding negotiation so that we can have later machine
revisions supercede earlier ones.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
signed_descriptor_digest has a length of DIGEST_LEN but the memset
used to fill it used DIGEST256_LEN.
Signed-off-by: Kris Katterjohn <katterjohn@gmail.com>