It tried to pick nodes for which only routerinfo_t items are set,
but without setting UseMicroDescriptors to 0. This won't work any
more, now that we're strict about using the right descriptor types
due to 25691/25692/25213.
In order to fix 25691 and 25692, we need to pass the "direct_conn"
flag to more places -- particularly when choosing single-hop
tunnels. The right way to do this involves having a couple more
functions accept router_crn_flags_t, rather than a big list of
boolean arguments.
This commit also makes sure that choose_good_exit_server_general()
honors the direct_conn flag, to fix 25691 and 25692.
In router_add_running_nodes_to_smartlist(), we had an inline
implementation of the logic from node_has_descriptor(), which should
be changed to node_has_preferred_descriptor().
This patch adds a new node_has_preferred_descriptor() function, and
replaces most users of node_has_descriptor() with it. That's an
important change, since as of d1874b4339 (our fix for #25213),
we are willing to say that a node has _some_ descriptor, but not the
_right_ descriptor for a particular use case.
Part of a fix for 25691 and 25692.
Now that we allow cpuworkers for dirport-only hosts (to fix 23693),
we need to allow dup_onion_keys() to succeed for them.
The change to construct_ntor_key_map() is for correctness,
but is not strictly necessary.
We recently merged a circuit cell queue size safeguard. This commit adds the
number of killed circuits that have reached the limit to the DoS heartbeat. It
now looks like this:
[notice] DoS mitigation since startup: 0 circuits killed with too many
cells. 0 circuits rejected, 0 marked addresses. 0 connections closed. 0
single hop clients refused.
Second thing that this patch does. It makes tor always print the DoS
mitigation heartbeat line (for a relay) even though no DoS mitigation have
been enabled. The reason is because we now kill circuits that have too many
cells regardless on if it is enabled or not but also it will give the operator
a chance to learn what is enabled with the heartbeat instead of suddenly
appearing when it is enabled by let say the consensus.
Fixes#25824
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit introduces the consensus parameter "circ_max_cell_queue_size"
which controls the maximum number of cells a circuit queue should have.
The default value is currently 50000 cells which is above what should be
expected but keeps us a margin of error for padding cells.
Related to this is #9072. Back in 0.2.4.14-alpha, we've removed that limit due
to a Guard discovery attack. Ticket #25226 details why we are putting back the
limit due to the memory pressure issue on relays.
Fixes#25226
Signed-off-by: David Goulet <dgoulet@torproject.org>
Add to the Denial of Service section of the man page an explanation about the
three different mitigation Tor has.
Fixes#25248.
Signed-off-by: David Goulet <dgoulet@torproject.org>
