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.
In addition to the comments in the ticket, couple hidden service options have
been improved to clarify the maximum and minimum values they can be set to.
Closes#21058
Signed-off-by: David Goulet <dgoulet@torproject.org>
Back when Roger had do do most of our testing on the moria host, we
needed a higher limit for the number of relays running on a single
IP address when that limit was shared with an authority. Nowadays,
the idea is pretty obsolete.
Also remove the router_addr_is_trusted_dir() function, which served
no other purpose.
Closes ticket 20960.
If there is some horrible bug in our ed25519 link authentication
code that causes us to label every single ed25519-having node as
non-running, we'll be glad we had this. Otherwise we can remove it
later.
I need to be able to turn on Ed25519 support in client generation
of extend cells so I can test it, but leave it off-by-default until
enough clients support it for us to turn it on for a bunch at once.
This is part of #15056 / prop#220.
The client addr is essentially meaningless in this context (yes, it is
possible to explicitly `bind()` AF_LOCAL client side sockets to a path,
but no one does it, and there are better ways to grant that sort of
feature if people want it like using `SO_PASSCRED`).