The interface is similar to the one exposed by `arti-client`: it
internally uses postage::watch to give a series of events showing
when a bootstrap status is changing.
Thanks to the existing state/driver separation in the DirMgr design
we don't need much new logic: each download state needs to expose
(internally) how far along it is in its download, which the
bootstrap code passes to the DirMgr if it has changed.
I believe that in the long run, we'll probably want to expose more
(or different) information here, and we'll want to process it
differently. With that in mind, I've made the API for
`DirBootstrapStatus` deliberately narrow, so that we can change its
of its internal later on without breaking code that depends on it.
(The information exposed by this commit is not yet summarized in
`arti-client`.)
Part of #96.
The purpose of a this API is to tell the user how far along Arti is
in getting bootstrapped, and if it's stuck, what it's stuck on.
This API doesn't yet expose any useful information: by the time it's
observable to a client, it's always "100% bootstrapped." But I'm
putting it in a MR now so that we can review the basic idea, and to
avoid conflicts with later work on tickets like #293 and #278.
This is part of #96.
This test should only fail very rarely (around 1/2.4e8) when guards
are chosen from a list of 20 with uniform probability. But that
wasn't what we were doing on the mock test network: we were choosing
from a list of 10 viable guards, with nonuniform probability.
As a fix, we change the test network probabilities so that the
guards _are_ chosen with a uniform probability for this test, and we
use a modified version of the test network where there are indeed 20
Guard-flagged relays with the required DirCache=2 protocol.
Closes#276.
Previously we could only configure one global tracing filter that
applied to stdout and journald. There was no support for log files,
either.
This patch fixes both issues, by substantially revising the
configuration format: There are now separate filters for each log
file, for journald, and for the console log. Because we want to
allow multiple logfiles, they have to go into an array in the
configuration.
The configuration logic has grown a bit complicated in its types,
since the tracing_subscriber crate would prefer to have the complete
structure of tracing Layers known statically. That's fine when you
know how many you have, and which kinds there will be, but for
the runtime-configuration case we need to mess around with
`Box<dyn Layer ...>`.
I also had to switch from tracing_subscriber's EnvFilter to its
Targets filter. It seems "EnvFilter" can only be applied as a Layer
in itself, and won't work as a Filter on an individual Layer.
Closes#166.
Closes#170.
The new `arti-bench` crate does a simple end-to-end benchmark test
embedding Arti: it generates some random data (of configurable amount,
depending on command-line parameters), and then sends said data back and
forth via Arti (which should be configured to use a local Chutney
network).
Additionally, the benchmark can also be run via a local SOCKS5 server
(in order to benchmark the performance via a local Chutney node, for
comparison).
The `tests/chutney/arti-bench.sh` sets up and tears down Chutney as
required to make this work.
This is very much a first cut; there are many things that should
eventually get added, such as support for multiple connections, JSON
output capabilities, running multiple tests, ...
This approach tries to preserve the current interface, but uses a
counter-based event backend to implement a coalescing stream of
events that can be represented as small integers. The advantage
here is that publishing events no longer needs to be a blocking
operation, since there is no queue to fill up.
This patch doesn't actually make anything reconfigurable, but it
does create an API that will tell you "you can't change the value of
that!" If the API looks reasonable, I can start making it possible
to change the values of individual items.
The rand crate's documentation says it's not okay to rely on StdRng
having reproducible output. So instead, let's switch to ChaCha12Rng
instead (which is what StrRng currently uses).
This implements a basic typed event broadcast mechanism, as described in
arti#230: consumers of the new `tor-events` crate can emit `TorEvent`
events, which others can consume via the `TorEventReceiver`.
Under the hood, the crate uses the `async-broadcast`
(https://github.com/smol-rs/async-broadcast) crate, and a
`futures::mpsc::UnboundedSender` for the event emitters; these are glued
together in the `EventReactor`, which must be run in a background thread
for things to work. (This is done so event sending is always cheap and
non-blocking, since `async-broadcast` senders don't have this
functionality.)
Additionally, the `TorEventKind` type is used to implement selective
event reception / emission: receivers can subscribe to certain event
types (and in fact start out receiving nothing), which filters the set
of events they receive. Having no subscribers for a given event type
means it won't even be emitted in the first place, making things more
efficient.
To do this at all neatly, I had to split out `tor-config` from
`arti-config` again, and putting the lower level stuff (paths,
builder errors) into tor-config. I also changed our use of
derive_builder to always use a common error type, to avoid
error type proliferation.
Rather like e8e9699c3c ("Get rid of
tor-proto's ChannelImpl, and use the reactor more instead"), this
admittedly rather large commit refactors the way circuits in `tor-proto`
work, centralising all of the logic in one large nonblocking reactor
which other things send messages into and out of, instead of having a
bunch of `-Impl` types that are protected by mutexes.
Congestion control becomes a lot simpler with this refactor, since the
reactor can manage both stream- and circuit-level congestion control
unilaterally without having to share this information with consumers,
meaning we can get rid of some locks.
The way streams work also changes, in order to facilitate better
handling of backpressure / fairness between streams: each stream now has
a set of channels to send and receive messages over, instead of sending
relay cells directly onto the channel (now, the reactor pulls messages
off each stream in each map, and tries to avoid doing so if it won't be
able to forward them yet).
Additionally, a lot of "close this circuit / stream" messages aren't
required any more, since that state is simply indicated by one end of a
channel going away. This should make cleanup a lot less brittle.
Getting all of this to work involved writing a fair deal of intricate
nonblocking code in Reactor::run_once that tries very hard to be mindful
of making backpressure work correctly (and congestion control); the old
code could get away with having tasks .await on things, but the new
reactor can't really do this (as it'd lock the reactor up), so has to do
everything in a nonblocking manner.
It requires tracing-subscriber 0.2, which is a lower version than we
want, and which causes trouble with our minimal-versions CI test.
There is a pending issue to fix this; we can reinstate tracing-test
once it is merged: https://github.com/dbrgn/tracing-test/pull/11
Instead of awkwardly sharing the internals of a `tor-proto` `Channel`
between the reactor task and any other tasks, move most of the internals
into the reactor and have other tasks communicate with the reactor via
message-passing to allocate circuits and send cells.
This makes a lot of things simple, and has convenient properties like
not needing to wrap the `Channel` in an `Arc` (though some places in the
code still do this for now).
A lot of test code required tweaking in order to deal with the refactor;
in fact, fixing the tests probably took longer than writing the mainline
code (!). Importantly, we now use `tokio`'s `tokio::test` annotation
instead of `async_test`, so that we can run things in the background
(which is required to have reactors running for the circuit tests).
This is an instance of #205, and also kind of #217.
We need this for the circuit timeout estimator (#57). It needs to
know "how recently have we got some incoming traffic", so that it
can tell whether a circuit has truly timed out, or whether the
entire network is down.
I'm implementing this with coarsetime, since we need to update these
in response to every single incoming cell, and we need the timestamp
operation to be _fast_.
(This reinstates an earlier commit, f30b2280, which I reverted
because we didn't need it at the time.)
Closes#179.
This switches out `arti`'s argument-parsing library with `clap`, which
is a lot more featureful (and very widely used within the Rust
ecosystem). We also now use a lot of `clap`'s features to improve the
CLI experience:
- The CLI now expects a subcommand (currently, either "help", or "proxy"
for the existing SOCKS proxy behaviour). This should let us add
additional non-SOCKS-proxy features to arti in future.
- `clap` supports default values determined at runtime, so the way the
default config file is loaded was changed: now, we determine the
OS-specific path for said file before invoking `clap`, so the help
command can show it properly.
- The behaviour of `tor_config` was also changed; now, one simply
specifies a list of configuration files to load, together with
whether they're required.
- That function also way overused generics; this has been fixed.
- Instead of using the ARTI_LOG environment variable to configure
logging, one now uses the `-l, --log-level` CLI option.
(The intent is for this option to be more discoverable by users.)
- The `proxy` subcommand allows the user to override the SOCKS port used
on the CLI without editing the config file.
Nick Mathewson
eta
Trinity Pointard
Neel Chauhan