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//! Implement a cache for onion descriptors and the facility to remember a bit
//! about onion service history.
use std::fmt::Debug;
use std::mem;
use std::panic::AssertUnwindSafe;
use std::sync::{Arc, Mutex, MutexGuard};
use std::time::{Duration, Instant};
use futures::task::{SpawnError, SpawnExt as _};
use futures::FutureExt as _;
use async_trait::async_trait;
use educe::Educe;
use either::Either::{self, *};
use postage::stream::Stream as _;
use tracing::{debug, error, trace};
use safelog::sensitive as sv;
use tor_basic_utils::define_accessor_trait;
use tor_circmgr::isolation::Isolation;
use tor_error::{debug_report, error_report, internal, Bug, ErrorReport as _};
use tor_hscrypto::pk::HsId;
use tor_netdir::NetDir;
use tor_rtcompat::Runtime;
use crate::isol_map;
use crate::{ConnError, HsClientConnector, HsClientSecretKeys};
slotmap::new_key_type! {
struct TableIndex;
}
/// Configuration, currently just some retry parameters
#[derive(Default, Debug)]
// This is not really public.
// It has to be `pub` because it appears in one of the methods in `MockableConnectorData`.
// That has to be because that trait is a bound on a parameter for `HsClientConnector`.
// `Config` is not re-exported. (This is isomorphic to the trait sealing pattern.)
//
// This means that this struct cannot live in the crate root, so we put it here.
pub struct Config {
/// Retry parameters
pub(crate) retry: tor_circmgr::CircuitTiming,
}
define_accessor_trait! {
/// Configuration for an HS client connector
///
/// If the HS client connector gains new configurabilities, this trait will gain additional
/// supertraits, as an API break.
///
/// Prefer to use `TorClientConfig`, which will always implement this trait.
//
// This arrangement is very like that for `CircMgrConfig`.
pub trait HsClientConnectorConfig {
circuit_timing: tor_circmgr::CircuitTiming,
}
}
/// Number of times we're willing to iterate round the state machine loop
///
/// **Not** the number of retries of failed descriptor downloads, circuits, etc.
///
/// The state machine loop is a condition variable loop.
/// It repeatedly transforms the [`ServiceState`] to try to get to `Open`,
/// converting stale data to `Closed` and `Closed` to `Working`, and so on.
/// This ought only to go forwards so in principle we could use an infinite loop.
/// But if we have a logic error, we want to crash eventually.
/// The `rechecks` counter is for detecting such a situation.
///
/// This is fairly arbitrary, but we shouldn't get anywhere near it.
///
/// Note that this is **not** a number of operational retries
/// of fallible retriable operations.
/// Such retries are handled in [`connect.rs`](crate::connect).
const MAX_RECHECKS: u32 = 10;
/// C Tor `MaxCircuitDirtiness`
///
/// As per
/// <https://gitlab.torproject.org/tpo/core/arti/-/issues/913#note_2914433>
///
/// And C Tor's `tor(1)`, which says:
///
/// > MaxCircuitDirtiness NUM
/// >
/// > Feel free to reuse a circuit that was first used at most NUM
/// > seconds ago, but never attach a new stream to a circuit that is
/// > too old. For hidden services, this applies to the last time a
/// > circuit was used, not the first. Circuits with streams
/// > constructed with SOCKS authentication via SocksPorts that have
/// > KeepAliveIsolateSOCKSAuth also remain alive for
/// > MaxCircuitDirtiness seconds after carrying the last such
/// > stream. (Default: 10 minutes)
///
/// However, we're not entirely sure this is the right behaviour.
/// See <https://gitlab.torproject.org/tpo/core/arti/-/issues/916>
///
// TODO SPEC: Explain C Tor `MaxCircuitDirtiness` behaviour
//
// TODO HS CFG: This should be configurable somehow
const RETAIN_CIRCUIT_AFTER_LAST_USE: Duration = Duration::from_secs(10 * 60);
/// How long to retain cached data about a hidden service
///
/// This is simply to reclaim space, not for correctness.
/// So we only check this during housekeeping, not operation.
///
/// The starting point for this interval is the last time we used the data,
/// or a circuit derived from it.
///
/// Note that this is a *maximum* for the length of time we will retain a descriptor;
/// HS descriptors' lifetimes (as declared in the descriptor) *are* honoured;
/// but that's done by the code in `connect.rs`, not here.
///
/// We're not sure this is the right value.
/// See <https://gitlab.torproject.org/tpo/core/arti/-/issues/916>
//
// TODO SPEC: State how long IPT and descriptor data should be retained after use
//
// TODO HS CFG: Perhaps this should be configurable somehow?
const RETAIN_DATA_AFTER_LAST_USE: Duration = Duration::from_secs(48 * 3600 /*hours*/);
/// Hidden services;, our connections to them, and history of connections, etc.
///
/// Table containing state of our ideas about services.
/// Data structure is keyed (indexed) by:
/// * `HsId`, hidden service identity
/// * any secret keys we are to use
/// * circuit isolation
///
/// We treat different values for any of the above as completely independent,
/// except that we try isolation joining (narrowing) if everything else matches.
///
/// In other words,
/// * Two HS connection requests cannot share state and effort
/// (descriptor downloads, descriptors, intro pt history)
/// unless the client authg keys to be used are the same.
/// * This criterion is checked before looking at isolations,
/// which may further restrict sharing:
/// Two HS connection requests will only share state subject to isolations.
///
/// Here "state and effort" includes underlying circuits such as hsdir circuits,
/// since each HS connection state will use `launch_specific_isolated` for those.
#[derive(Default, Debug)]
pub(crate) struct Services<D: MockableConnectorData> {
/// The actual records of our connections/attempts for each service, as separated
records: isol_map::MultikeyIsolatedMap<TableIndex, HsId, HsClientSecretKeys, ServiceState<D>>,
/// Configuration
///
/// `Arc` so that it can be shared with individual hs connector tasks
config: Arc<Config>,
}
/// Entry in the 2nd-level lookup array
#[allow(dead_code)] // This alias is here for documentation if nothing else
type ServiceRecord<D> = isol_map::Record<HsClientSecretKeys, ServiceState<D>>;
/// Value in the `Services` data structure
///
/// State and history of of our connections, including connection to any connection task.
///
/// `last_used` is used to expire data eventually.
//
// TODO unify this with channels and circuits. See arti#778.
#[derive(Educe)]
#[educe(Debug)]
enum ServiceState<D: MockableConnectorData> {
/// We don't have a circuit
Closed {
/// The state
data: D,
/// Last time we touched this, including reuse
last_used: Instant,
},
/// We have an open circuit, which we can (hopefully) just use
Open {
/// The state
data: D,
/// The circuit
#[educe(Debug(ignore))]
circuit: Arc<D::ClientCirc>,
/// Last time we touched this, including reuse
///
/// This is set when we created the circuit, and updated when we
/// hand out this circuit again in response to a new request.
///
/// We believe this mirrors C Tor behaviour;
/// see [`RETAIN_CIRCUIT_AFTER_LAST_USE`].
last_used: Instant,
/// We have a task that will close the circuit when required
///
/// This field serves to require construction sites of Open
/// to demonstrate that there *is* an expiry task.
/// In the future, it may also serve to cancel old expiry tasks.
circuit_expiry_task: CircuitExpiryTask,
},
/// We have a task trying to find the service and establish the circuit
///
/// CachedData is owned by the task.
Working {
/// Signals instances of `get_or_launch_connection` when the task completes
barrier_recv: postage::barrier::Receiver,
/// Where the task will store the error.
///
/// Lock hierarchy: this lock is "inside" the big lock on `Services`.
error: Arc<Mutex<Option<ConnError>>>,
},
/// Dummy value for use with temporary mem replace
Dummy,
}
impl<D: MockableConnectorData> ServiceState<D> {
/// Make a new (blank) `ServiceState::Closed`
fn blank(runtime: &impl Runtime) -> Self {
ServiceState::Closed {
data: D::default(),
last_used: runtime.now(),
}
}
}
/// "Continuation" return type from `obtain_circuit_or_continuation_info`
type Continuation = (Arc<Mutex<Option<ConnError>>>, postage::barrier::Receiver);
/// Represents a task which is waiting to see when the circuit needs to be expired
///
/// TODO: Replace this with a task handle that cancels the task when dropped.
/// Until then, if the circuit is closed before then, the expiry task will
/// uselessly wake up some time later.
#[derive(Debug)] // Not Clone
struct CircuitExpiryTask {}
// impl Drop already, partly to allow explicit drop(CircuitExpiryTask) without clippy complaint
impl Drop for CircuitExpiryTask {
fn drop(&mut self) {}
}
/// Obtain a circuit from the `Services` table, or return a continuation
///
/// This is the workhorse function for `get_or_launch_connection`.
///
/// `get_or_launch_connection`, together with `obtain_circuit_or_continuation_info`,
/// form a condition variable loop:
///
/// We check to see if we have a circuit. If so, we return it.
/// Otherwise, we make sure that a circuit is being constructed,
/// and then go into a condvar wait;
/// we'll be signaled when the construction completes.
///
/// So the connection task we spawn does not return the circuit, or error,
/// via an inter-task stream.
/// It stores it in the data structure and wakes up all the client tasks.
/// (This means there is only one success path for the client task code.)
///
/// There are some wrinkles:
///
/// ### Existence of this as a separate function
///
/// The usual structure for a condition variable loop would be something like this:
///
/// ```rust,ignore
/// loop {
/// test state and maybe break;
/// cv.wait(guard).await; // consumes guard, unlocking after enqueueing us as a waiter
/// guard = lock();
/// }
/// ```
///
/// However, Rust does not currently understand that the mutex is not
/// actually a captured variable held across an await point,
/// when the variable is consumed before the await, and re-stored afterwards.
/// As a result, the async future becomes erroneously `!Send`:
/// <https://github.com/rust-lang/rust/issues/104883>.
/// We want the unstable feature `-Zdrop-tracking`:
/// <https://github.com/rust-lang/rust/issues/97331>.
///
/// Instead, to convince the compiler, we must use a scope-based drop of the mutex guard.
/// That means converting the "test state and maybe break" part into a sub-function.
/// That's what this function is.
///
/// It returns `Right` if the loop should be exited, returning the circuit to the caller.
/// It returns `Left` if the loop needs to do a condition variable wait.
///
/// ### We're using a barrier as a condition variable
///
/// We want to be signaled when the task exits. Indeed, *only* when it exits.
/// This functionality is most conveniently in a `postage::barrier`.
///
/// ### Nested loops
///
/// Sometimes we want to go round again *without* unlocking.
/// Sometimes we must unlock and wait and relock.
///
/// The drop tracking workaround (see above) means we have to do these two
/// in separate scopes.
/// So there are two nested loops: one here, and one in `get_or_launch_connection`.
/// They both use the same backstop rechecks counter.
fn obtain_circuit_or_continuation_info<D: MockableConnectorData>(
connector: &HsClientConnector<impl Runtime, D>,
netdir: &Arc<NetDir>,
hsid: &HsId,
secret_keys: &HsClientSecretKeys,
table_index: TableIndex,
rechecks: &mut impl Iterator,
mut guard: MutexGuard<'_, Services<D>>,
) -> Result<Either<Continuation, Arc<D::ClientCirc>>, ConnError> {
let blank_state = || ServiceState::blank(&connector.runtime);
for _recheck in rechecks {
let record = guard
.records
.by_index_mut(table_index)
.ok_or_else(|| internal!("guard table entry vanished!"))?;
let state = &mut **record;
trace!("HS conn state: {state:?}");
let (data, barrier_send) = match state {
ServiceState::Open {
data: _,
circuit,
last_used,
circuit_expiry_task: _,
} => {
let now = connector.runtime.now();
if !D::circuit_is_ok(circuit) {
// Well that's no good, we need a fresh one, but keep the data
let data = match mem::replace(state, ServiceState::Dummy) {
ServiceState::Open {
data,
last_used: _,
circuit: _,
circuit_expiry_task: _,
} => data,
_ => panic!("state changed between matches"),
};
*state = ServiceState::Closed {
data,
last_used: now,
};
continue;
}
*last_used = now;
// No need to tell expiry task about revised expiry time;
// it will see the new last_used when it wakes up at the old expiry time.
return Ok::<_, ConnError>(Right(circuit.clone()));
}
ServiceState::Working {
barrier_recv,
error,
} => {
if !matches!(
barrier_recv.try_recv(),
Err(postage::stream::TryRecvError::Pending)
) {
// This information is stale; the task no longer exists.
// We want information from a fresh task.
*state = blank_state();
continue;
}
let barrier_recv = barrier_recv.clone();
// This clone of the error field Arc<Mutex<..>> allows us to collect errors
// which happened due to the currently-running task, which we have just
// found exists. Ie, it will see errors that occurred after we entered
// `get_or_launch`. Stale errors, from previous tasks, were cleared above.
let error = error.clone();
// Wait for the task to complete (at which point it drops the barrier)
return Ok(Left((error, barrier_recv)));
}
ServiceState::Closed { .. } => {
let (barrier_send, barrier_recv) = postage::barrier::channel();
let data = match mem::replace(
state,
ServiceState::Working {
barrier_recv,
error: Arc::new(Mutex::new(None)),
},
) {
ServiceState::Closed { data, .. } => data,
_ => panic!("state changed between matches"),
};
(data, barrier_send)
}
ServiceState::Dummy => {
*state = blank_state();
return Err(internal!("HS connector found dummy state").into());
}
};
// Make a connection
let runtime = &connector.runtime;
let connector = (*connector).clone();
let config = guard.config.clone();
let netdir = netdir.clone();
let secret_keys = secret_keys.clone();
let hsid = *hsid;
let connect_future = async move {
let mut data = data;
let got = AssertUnwindSafe(D::connect(
&connector,
netdir,
config,
hsid,
&mut data,
secret_keys,
))
.catch_unwind()
.await
.unwrap_or_else(|_| {
data = D::default();
Err(internal!("hidden service connector task panicked!").into())
});
let now = connector.runtime.now();
let last_used = now;
let got = got.and_then(|circuit| {
let circuit_expiry_task = ServiceState::spawn_circuit_expiry_task(
&connector,
hsid,
table_index,
last_used,
now,
)
.map_err(|cause| ConnError::Spawn {
spawning: "circuit expiry task",
cause: cause.into(),
})?;
Ok((circuit, circuit_expiry_task))
});
let got_error = got.as_ref().map(|_| ()).map_err(Clone::clone);
// block for handling inability to store
let stored = async {
let mut guard = connector.services()?;
let record = guard
.records
.by_index_mut(table_index)
.ok_or_else(|| internal!("HS table entry removed while task running"))?;
// Always match this, so we check what we're overwriting
let state = &mut **record;
let error_store = match state {
ServiceState::Working { error, .. } => error,
_ => return Err(internal!("HS task found state other than Working")),
};
match got {
Ok((circuit, circuit_expiry_task)) => {
*state = ServiceState::Open {
data,
circuit,
last_used,
circuit_expiry_task,
}
}
Err(error) => {
let mut error_store = error_store
.lock()
.map_err(|_| internal!("Working error poisoned, cannot store error"))?;
*error_store = Some(error);
}
};
Ok(())
}
.await;
match (got_error, stored) {
(Ok::<(), ConnError>(()), Ok::<(), Bug>(())) => {}
(Err(got_error), Ok(())) => {
debug_report!(got_error, "HS connection failure for {}", sv(hsid));
}
(Ok(()), Err(bug)) => {
error_report!(
bug,
"internal error storing built HS circuit for {}",
sv(hsid)
);
}
(Err(got_error), Err(bug)) => {
// We're reporting two errors, so we'll construct the event
// manually.
error!(
"internal error storing HS connection error for {}: {}; {}",
sv(hsid),
got_error.report(),
bug.report(),
);
}
};
drop(barrier_send);
};
runtime
.spawn_obj(Box::new(connect_future).into())
.map_err(|cause| ConnError::Spawn {
spawning: "connection task",
cause: cause.into(),
})?;
}
Err(internal!("HS connector state management malfunction (exceeded MAX_RECHECKS").into())
}
impl<D: MockableConnectorData> Services<D> {
/// Create a new empty `Services`
pub(crate) fn new(config: Config) -> Self {
Services {
records: Default::default(),
config: Arc::new(config),
}
}
/// Connect to a hidden service
// We *do* drop guard. There is *one* await point, just after drop(guard).
pub(crate) async fn get_or_launch_connection(
connector: &HsClientConnector<impl Runtime, D>,
netdir: &Arc<NetDir>,
hs_id: HsId,
isolation: Box<dyn Isolation>,
secret_keys: HsClientSecretKeys,
) -> Result<Arc<D::ClientCirc>, ConnError> {
let blank_state = || ServiceState::blank(&connector.runtime);
let mut rechecks = 0..MAX_RECHECKS;
let mut obtain = |table_index, guard| {
obtain_circuit_or_continuation_info(
connector,
netdir,
&hs_id,
&secret_keys,
table_index,
&mut rechecks,
guard,
)
};
let mut got;
let table_index;
{
let mut guard = connector.services()?;
let services = &mut *guard;
trace!("HS conn get_or_launch: {hs_id:?} {isolation:?} {secret_keys:?}");
//trace!("HS conn services: {services:?}");
table_index =
services
.records
.index_or_insert_with(&hs_id, &secret_keys, isolation, blank_state);
let guard = guard;
got = obtain(table_index, guard);
}
loop {
// The parts of this loop which run after a `Left` is returned
// logically belong in the case in `obtain_circuit_or_continuation_info`
// for `ServiceState::Working`, where that function decides we need to wait.
// This code has to be out here to help the compiler's drop tracking.
{
// Block to scope the acquisition of `error`, a guard
// for the mutex-protected error field in the state,
// and, for neatness, barrier_recv.
let (error, mut barrier_recv) = match got? {
Right(ret) => return Ok(ret),
Left(continuation) => continuation,
};
barrier_recv.recv().await;
let error = error
.lock()
.map_err(|_| internal!("Working error poisoned"))?;
if let Some(error) = &*error {
return Err(error.clone());
}
}
let guard = connector.services()?;
got = obtain(table_index, guard);
}
}
/// Perform housekeeping - delete data we aren't interested in any more
pub(crate) fn run_housekeeping(&mut self, now: Instant) {
self.expire_old_data(now);
}
/// Delete data we aren't interested in any more
fn expire_old_data(&mut self, now: Instant) {
self.records
.retain(|hsid, record, _table_index| match &**record {
ServiceState::Closed { data: _, last_used } => {
let Some(expiry_time) = last_used.checked_add(RETAIN_DATA_AFTER_LAST_USE)
else {
return false;
};
now <= expiry_time
}
ServiceState::Open { .. } | ServiceState::Working { .. } => true,
ServiceState::Dummy { .. } => {
error!("found dummy data during HS housekeeping, for {}", sv(hsid));
false
}
});
}
}
impl<D: MockableConnectorData> ServiceState<D> {
/// Spawn a task that will drop our reference to the rendezvous circuit
/// at `table_index` when it has gone too long without any use.
///
/// According to [`RETAIN_CIRCUIT_AFTER_LAST_USE`].
//
// As it happens, this function is always called with `last_used` equal to `now`,
// but we pass separate arguments for clarity.
fn spawn_circuit_expiry_task(
connector: &HsClientConnector<impl Runtime, D>,
hsid: HsId,
table_index: TableIndex,
last_used: Instant,
now: Instant,
) -> Result<CircuitExpiryTask, SpawnError> {
/// Returns the duration until expiry, or `None` if it should expire now
fn calculate_expiry_wait(last_used: Instant, now: Instant) -> Option<Duration> {
let expiry = last_used
.checked_add(RETAIN_CIRCUIT_AFTER_LAST_USE)
.or_else(|| {
error!("time overflow calculating HS circuit expiry, killing circuit!");
None
})?;
let wait = expiry.checked_duration_since(now).unwrap_or_default();
if wait == Duration::ZERO {
return None;
}
Some(wait)
}
let mut maybe_wait = calculate_expiry_wait(last_used, now);
let () = connector.runtime.spawn({
let connector = connector.clone();
async move {
// This loop is slightly odd. The wait ought naturally to be at the end,
// but that would mean a useless re-lock and re-check right after creation,
// or jumping into the middle of the loop.
loop {
if let Some(yes_wait) = maybe_wait {
connector.runtime.sleep(yes_wait).await;
}
// If it's None, we can't rely on that to say we should expire it,
// since that information crossed a time when we didn't hold the lock.
let Ok(mut guard) = connector.services() else {
break;
};
let Some(record) = guard.records.by_index_mut(table_index) else {
break;
};
let state = &mut **record;
let last_used = match state {
ServiceState::Closed { .. } => break,
ServiceState::Open { last_used, .. } => *last_used,
ServiceState::Working { .. } => break, // someone else will respawn
ServiceState::Dummy => break, // someone else will (report and) fix
};
maybe_wait = calculate_expiry_wait(last_used, connector.runtime.now());
if maybe_wait.is_none() {
match mem::replace(state, ServiceState::Dummy) {
ServiceState::Open {
data,
circuit,
last_used,
circuit_expiry_task,
} => {
debug!("HS connection expires: {hsid}");
drop(circuit);
drop(circuit_expiry_task); // that's us
*state = ServiceState::Closed { data, last_used };
break;
}
_ => panic!("state now {state:?} even though we just saw it Open"),
}
}
}
}
})?;
Ok(CircuitExpiryTask {})
}
}
/// Mocking for actual HS connection work, to let us test the `Services` state machine
//
// Does *not* mock circmgr, chanmgr, etc. - those won't be used by the tests, since our
// `connect` won't call them. But mocking them pollutes many types with `R` and is
// generally tiresome. So let's not. Instead the tests can make dummy ones.
//
// This trait is actually crate-private, since it isn't re-exported, but it must
// be `pub` because it appears as a default for a type parameter in HsClientConnector.
#[async_trait]
pub trait MockableConnectorData: Default + Debug + Send + Sync + 'static {
/// Client circuit
type ClientCirc: Sync + Send + 'static;
/// Mock state
type MockGlobalState: Clone + Sync + Send + 'static;
/// Connect
async fn connect<R: Runtime>(
connector: &HsClientConnector<R, Self>,
netdir: Arc<NetDir>,
config: Arc<Config>,
hsid: HsId,
data: &mut Self,
secret_keys: HsClientSecretKeys,
) -> Result<Arc<Self::ClientCirc>, ConnError>;
/// Is circuit OK? Ie, not `.is_closing()`.
fn circuit_is_ok(circuit: &Self::ClientCirc) -> bool;
}
#[cfg(test)]
pub(crate) mod test {
// @@ begin test lint list maintained by maint/add_warning @@
#![allow(clippy::bool_assert_comparison)]
#![allow(clippy::clone_on_copy)]
#![allow(clippy::dbg_macro)]
#![allow(clippy::mixed_attributes_style)]
#![allow(clippy::print_stderr)]
#![allow(clippy::print_stdout)]
#![allow(clippy::single_char_pattern)]
#![allow(clippy::unwrap_used)]
#![allow(clippy::unchecked_duration_subtraction)]
#![allow(clippy::useless_vec)]
#![allow(clippy::needless_pass_by_value)]
//! <!-- @@ end test lint list maintained by maint/add_warning @@ -->
use super::*;
use crate::*;
use futures::{poll, SinkExt};
use std::fmt;
use std::task::Poll::{self, *};
use tokio::pin;
use tokio_crate as tokio;
use tor_rtcompat::{test_with_one_runtime, SleepProvider};
use tor_rtmock::MockRuntime;
use tracing_test::traced_test;
use ConnError as E;
#[derive(Debug, Default)]
struct MockData {
connect_called: usize,
}
/// Type indicating what our `connect()` should return; it always makes a fresh MockCirc
type MockGive = Poll<Result<(), E>>;
#[derive(Debug, Clone)]
struct MockGlobalState {
// things will appear here when we have more sophisticated tests
give: postage::watch::Receiver<MockGive>,
}
#[derive(Clone, Educe)]
#[educe(Debug)]
struct MockCirc {
#[educe(Debug(method = "debug_arc_mutex"))]
ok: Arc<Mutex<bool>>,
connect_called: usize,
}
fn debug_arc_mutex(val: &Arc<Mutex<impl Debug>>, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "@{:?}", Arc::as_ptr(val))?;
let guard = val.lock();
let guard = guard.or_else(|g| {
write!(f, ",POISON")?;
Ok::<_, fmt::Error>(g.into_inner())
})?;
write!(f, " ")?;
Debug::fmt(&*guard, f)
}
impl PartialEq for MockCirc {
fn eq(&self, other: &MockCirc) -> bool {
Arc::ptr_eq(&self.ok, &other.ok)
}
}
impl MockCirc {
fn new(connect_called: usize) -> Self {
let ok = Arc::new(Mutex::new(true));
MockCirc { ok, connect_called }
}
}
#[async_trait]
impl MockableConnectorData for MockData {
type ClientCirc = MockCirc;
type MockGlobalState = MockGlobalState;
async fn connect<R: Runtime>(
connector: &HsClientConnector<R, MockData>,
_netdir: Arc<NetDir>,
_config: Arc<Config>,
_hsid: HsId,
data: &mut MockData,
_secret_keys: HsClientSecretKeys,
) -> Result<Arc<Self::ClientCirc>, E> {
data.connect_called += 1;
let make = {
let connect_called = data.connect_called;
move |()| Arc::new(MockCirc::new(connect_called))
};
let mut give = connector.mock_for_state.give.clone();
if let Ready(ret) = &*give.borrow() {
return ret.clone().map(make);
}
loop {
match give.recv().await.expect("EOF on mock_global_state stream") {
Pending => {}
Ready(ret) => return ret.map(make),
}
}
}
fn circuit_is_ok(circuit: &Self::ClientCirc) -> bool {
*circuit.ok.lock().unwrap()
}
}
/// Makes a non-empty `HsClientSecretKeys`, containing (somehow) `kk`
fn mk_keys(kk: u8) -> HsClientSecretKeys {
let mut ss = [0_u8; 32];
ss[0] = kk;
let keypair = tor_llcrypto::pk::ed25519::Keypair::from_bytes(&ss);
let mut b = HsClientSecretKeysBuilder::default();
#[allow(deprecated)]
b.ks_hsc_intro_auth(keypair.into());
b.build().unwrap()
}
fn mk_hsconn<R: Runtime>(
runtime: R,
) -> (
HsClientConnector<R, MockData>,
HsClientSecretKeys,
postage::watch::Sender<MockGive>,
) {
let chanmgr = tor_chanmgr::ChanMgr::new(
runtime.clone(),
&Default::default(),
tor_chanmgr::Dormancy::Dormant,
&Default::default(),
);
let guardmgr = tor_guardmgr::GuardMgr::new(
runtime.clone(),
tor_persist::TestingStateMgr::new(),
&tor_guardmgr::TestConfig::default(),
)
.unwrap();
let circmgr = tor_circmgr::CircMgr::new(
&tor_circmgr::TestConfig::default(),
tor_persist::TestingStateMgr::new(),
&runtime,
Arc::new(chanmgr),
guardmgr,
)
.unwrap();
let circpool = HsCircPool::new(&circmgr);
let (give_send, give) = postage::watch::channel_with(Ready(Ok(())));
let mock_for_state = MockGlobalState { give };
#[allow(clippy::let_and_return)] // we'll probably add more in this function
let hscc = HsClientConnector {
runtime,
circpool,
services: Default::default(),
mock_for_state,
};
let keys = HsClientSecretKeysBuilder::default().build().unwrap();
(hscc, keys, give_send)
}
#[allow(clippy::unnecessary_wraps)]
fn mk_isol(s: &str) -> Option<NarrowableIsolation> {
Some(NarrowableIsolation(s.into()))
}
async fn launch_one(
hsconn: &HsClientConnector<impl Runtime, MockData>,
id: u8,
secret_keys: &HsClientSecretKeys,
isolation: Option<NarrowableIsolation>,
) -> Result<Arc<MockCirc>, ConnError> {
let netdir = tor_netdir::testnet::construct_netdir()
.unwrap_if_sufficient()
.unwrap();
let netdir = Arc::new(netdir);
let hs_id = {
let mut hs_id = [0_u8; 32];
hs_id[0] = id;
hs_id.into()
};
#[allow(clippy::redundant_closure)] // srsly, that would be worse
let isolation = isolation.unwrap_or_default().into();
Services::get_or_launch_connection(hsconn, &netdir, hs_id, isolation, secret_keys.clone())
.await
}
#[derive(Default, Debug, Clone)]
// TODO move this to tor-circmgr under a test feature?
pub(crate) struct NarrowableIsolation(pub(crate) String);
impl tor_circmgr::isolation::IsolationHelper for NarrowableIsolation {
fn compatible_same_type(&self, other: &Self) -> bool {
self.join_same_type(other).is_some()
}
fn join_same_type(&self, other: &Self) -> Option<Self> {
Some(if self.0.starts_with(&other.0) {
self.clone()
} else if other.0.starts_with(&self.0) {
other.clone()
} else {
return None;
})
}
}
#[test]
#[traced_test]
fn simple() {
test_with_one_runtime!(|runtime| async {
let (hsconn, keys, _give_send) = mk_hsconn(runtime);
let circuit = launch_one(&hsconn, 0, &keys, None).await.unwrap();
eprintln!("{:?}", circuit);
});
}
#[test]
#[traced_test]
fn expiry() {
MockRuntime::test_with_various(|runtime| async move {
// This is the amount by which we adjust clock advances to make sure we
// hit more or less than a particular value, to avoid edge cases and
// cope with real time advancing too.
// This does *not* represent an actual delay to real test runs.
const TIMEOUT_SLOP: Duration = Duration::from_secs(10);
let (hsconn, keys, _give_send) = mk_hsconn(runtime.clone());
let advance = |duration| {
let hsconn = hsconn.clone();
let runtime = &runtime;
async move {
// let expiry task get going and choose its expiry (wakeup) time
runtime.progress_until_stalled().await;
// TODO: Make this use runtime.advance_by() when that's not very slow
runtime.mock_sleep().advance(duration);
// let expiry task run
runtime.progress_until_stalled().await;
hsconn.services().unwrap().run_housekeeping(runtime.now());
}
};
// make circuit1
let circuit1 = launch_one(&hsconn, 0, &keys, None).await.unwrap();
// expire it
advance(RETAIN_CIRCUIT_AFTER_LAST_USE + TIMEOUT_SLOP).await;
// make circuit2 (a)
let circuit2a = launch_one(&hsconn, 0, &keys, None).await.unwrap();
assert_ne!(circuit1, circuit2a);
// nearly expire it, then reuse it
advance(RETAIN_CIRCUIT_AFTER_LAST_USE - TIMEOUT_SLOP).await;
let circuit2b = launch_one(&hsconn, 0, &keys, None).await.unwrap();
assert_eq!(circuit2a, circuit2b);
// nearly expire it again, then reuse it
advance(RETAIN_CIRCUIT_AFTER_LAST_USE - TIMEOUT_SLOP).await;
let circuit2c = launch_one(&hsconn, 0, &keys, None).await.unwrap();
assert_eq!(circuit2a, circuit2c);
// actually expire it
advance(RETAIN_CIRCUIT_AFTER_LAST_USE + TIMEOUT_SLOP).await;
let circuit3 = launch_one(&hsconn, 0, &keys, None).await.unwrap();
assert_ne!(circuit2c, circuit3);
assert_eq!(circuit3.connect_called, 3);
advance(RETAIN_DATA_AFTER_LAST_USE + Duration::from_secs(10)).await;
let circuit4 = launch_one(&hsconn, 0, &keys, None).await.unwrap();
assert_eq!(circuit4.connect_called, 1);
});
}
#[test]
#[traced_test]
fn coalesce() {
test_with_one_runtime!(|runtime| async {
let (hsconn, keys, mut give_send) = mk_hsconn(runtime);
give_send.send(Pending).await.unwrap();
let c1f = launch_one(&hsconn, 0, &keys, None);
pin!(c1f);
for _ in 0..10 {
assert!(poll!(&mut c1f).is_pending());
}
// c2f will find Working
let c2f = launch_one(&hsconn, 0, &keys, None);
pin!(c2f);
for _ in 0..10 {
assert!(poll!(&mut c1f).is_pending());
assert!(poll!(&mut c2f).is_pending());
}
give_send.send(Ready(Ok(()))).await.unwrap();
let c1 = c1f.await.unwrap();
let c2 = c2f.await.unwrap();
assert_eq!(c1, c2);
// c2 will find Open
let c3 = launch_one(&hsconn, 0, &keys, None).await.unwrap();
assert_eq!(c1, c3);
assert_ne!(c1, launch_one(&hsconn, 1, &keys, None).await.unwrap());
assert_ne!(
c1,
launch_one(&hsconn, 0, &mk_keys(42), None).await.unwrap()
);
let c_isol_1 = launch_one(&hsconn, 0, &keys, mk_isol("a")).await.unwrap();
assert_eq!(c1, c_isol_1); // We can reuse, but now we've narrowed the isol
let c_isol_2 = launch_one(&hsconn, 0, &keys, mk_isol("b")).await.unwrap();
assert_ne!(c1, c_isol_2);
});
}
}