A bit cleaner especially that the next commit(s) will make the consensus param
interface private to hs_dos.c so we expose as little as we can outside of the
subsystem.
Part of #30924
Signed-off-by: David Goulet <dgoulet@torproject.org>
Make it clear that these functions return the consensus param only.
Introduction point can not set those values with a torrc option.
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit add the hs_dos.{c|h} file that has the purpose of having the
anti-DoS code for onion services.
At this commit, it only has one which is a function that decides if an
INTRODUCE2 can be sent on the given introduction service circuit (S<->IP)
using a simple token bucket.
The rate per second is 25 and allowed burst to 200.
Basic defenses on #15516.
Signed-off-by: David Goulet <dgoulet@torproject.org>