Since 0.2.4, tor uses EWMA circuit policy to prioritize. The previous
algorithm, round-robin, hasn't been used since then but was still used as a
fallback.
Now that EWMA is mandatory, remove that code entirely and enforce a cmux
policy to be set.
This is part of a circuitmux cleanup to improve performance and reduce
complexity in the code. We'll be able to address future optimization with this
work.
Closes#25268
Signed-off-by: David Goulet <dgoulet@torproject.org>
At this commit, the SocksSocketsGroupWritable option is renamed to
UnixSocksGroupWritable. A deprecated warning is triggered if the old option is
used and tor will use it properly.
Fixes#24343
Signed-off-by: David Goulet <dgoulet@torproject.org>
Because this touches too many commits at once, it is made into one single
commit.
Remove the use of "tenths" for the circuit rate to simplify things. We can
only refill the buckets at best once every second because of the use of
approx_time() and our token system is set to be 1 token = 1 circuit so make
the rate a flat integer of circuit per second.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Implement a basic connection tracking that counts the number of concurrent
connections when they open and close.
This commit also adds the circuit creation mitigation data structure that will
be needed at later commit to keep track of the circuit rate.
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit introduces the src/or/dos.{c|h} files that contains the code for
the Denial of Service mitigation subsystem. It currently contains basic
functions to initialize and free the subsystem. They are used at this commit.
The torrc options and consensus parameters are defined at this commit and
getters are implemented.
Signed-off-by: David Goulet <dgoulet@torproject.org>
We've been seeing problems with destroy cells queues taking up a
huge amount of RAM. We can mitigate this, since while a full packed
destroy cell takes 514 bytes, we only need 5 bytes to remember a
circuit ID and a reason.
Fixes bug 24666. Bugfix on 0.2.5.1-alpha, when destroy cell queues
were introduced.
This patch adds support for MainloopStats that allow developers to get
main event loop statistics via Tor's heartbeat status messages. The new
status log message will show how many succesful, erroneous, and idle
event loop iterations we have had.
See: https://bugs.torproject.org/24605
This patch adds support for Android's logging subsystem in Tor. When
debugging Android applications it is useful to be able to collect
information about the application running on the platform via the
various system services that is available on the platform.
This patch allows you to add "Log notice android" to your torrc and have
Tor send everything above and including the notice severity to Android's
ring buffer which can be inspected using the 'adb logcat' program.
See: https://bugs.torproject.org/24362
The goal here is to replace our use of msec-based timestamps with
something less precise, but easier to calculate. We're doing this
because calculating lots of msec-based timestamps requires lots of
64/32 division operations, which can be inefficient on 32-bit
platforms.
We make sure that these stamps can be calculated using only the
coarse monotonic timer and 32-bit bitwise operations.
By convention, the torrc options that the user sets are
unchangeable. If we need to change them, we should be using a copy
that's stored in another field
To avoid trouble, I'm keeping DataDirectory as the name for the
field that the rest of Tor uses, and using DataDirectory_option for
the confparse-controlled field.
This commit also modernizes some older string handling code in the
DataDirectory normalization function.
