Mike Perry authored Sep 22, 2016 and Nick Mathewson committed May 08, 2017

Checking all of these parameter lists for every single connection every second
seems like it could be an expensive waste.

Updating globally cached versions when there is a new consensus will still
allow us to apply consensus parameter updates to all existing connections
immediately.

Mike Perry authored Sep 22, 2016 and Nick Mathewson committed May 08, 2017

IMO, these tests should be calling options_init() to properly set everything
to default values, but when that is done, about a dozen tests fail. Setting
the one default value that broke the tests for my branch. Sorry for being
lame.

Mike Perry authored Sep 06, 2016 and Nick Mathewson committed May 08, 2017

The option was deprecated by bug #17592.

Mike Perry authored Nov 14, 2015 and Nick Mathewson committed May 08, 2017

Accomplished via the following:

1. Use NETINFO cells to determine if both peers will agree on canonical
   status. Prefer connections where they agree to those where they do not.
2. Alter channel_is_better() to prefer older orconns in the case of multiple
   canonical connections, and use the orconn with more circuits on it in case
   of age ties.

Also perform some hourly accounting on how many of these types of connections
there are and log it at info or notice level.

Mike Perry authored Feb 21, 2017 and Nick Mathewson committed May 08, 2017

This unifies CircuitIdleTimeout and PredictedCircsRelevanceTime into a single
option, and randomizes it.

It also gives us control over the default value as well as relay-to-relay
connection lifespan through the consensus.

Conflicts:
	src/or/circuituse.c
	src/or/config.c
	src/or/main.c
	src/test/testing_common.c

Mike Perry authored Sep 06, 2016 and Nick Mathewson committed May 08, 2017

This defense will cause Cisco, Juniper, Fortinet, and other routers operating
in the default configuration to collapse netflow records that would normally
be split due to the 15 second flow idle timeout.

Collapsing these records should greatly reduce the utility of default netflow
data for correlation attacks, since all client-side records should become 30
minute chunks of total bytes sent/received, rather than creating multiple
separate records for every webpage load/ssh command interaction/XMPP chat/whatever
else happens to be inactive for more than 15 seconds.

The defense adds consensus parameters to govern the range of timeout values
for sending padding packets, as well as for keeping connections open.

The defense only sends padding when connections are otherwise inactive, and it
does not pad connections used solely for directory traffic at all. By default
it also doesn't pad inter-relay connections.

Statistics on the total padding in the last 24 hours are exported to the
extra-info descriptors.

scan-build found that we we checking UseEntryGuards twice.

Fixes bug 21492.

Bug found with clang scan-build.  Fixes bug on f63e06d3.
Bug not present in any released Tor.

Fix on fc58c37e. Not in any released tor

Instead of returning 404 error code, this led to a NULL pointer being used and
thus a crash of tor.

Fixes #21471

Signed-off-by: David Goulet <dgoulet@torproject.org>

Closes 21450; patch from teor.

This is an extra fix for bug 21278: it ensures that these
descriptors and platforms will never be listed in a legit consensus.