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//! Administrative RPC functionality.
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//!
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//! In general, RPC function is "administrative", and requires superuser access,
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//! whenever it can affect other applications.
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//!
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//! This is not a perfect sandbox: applications can _always_ interfere with one another's traffic by
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//! consuming resources (like bandwidth or CPU) in a way that introduces side channels.
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use arti_client::{TorClient, rpc::ClientStatusInfo};
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use derive_deftly::Deftly;
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use futures::{FutureExt as _, SinkExt as _, StreamExt as _, select_biased};
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use std::sync::Arc;
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use tor_rpcbase::{self as rpc};
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use tor_rtcompat::Runtime;
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use crate::reload_cfg::LaunchableTorClient;
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/// An object representing superuser access to Arti over an RPC session.
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///
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/// In general, RPC function is "administrative", and requires superuser access,
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/// whenever it can affect other applications.
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#[derive(Deftly)]
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#[derive_deftly(rpc::Object)]
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pub(super) struct RpcSuperuser<R: Runtime> {
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    /// A view of the underlying TorClient managed by this RpcSuperuser object.
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    tor_client: Arc<TorClient<R>>,
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    /// A wrapper around `tor_client` with the ability to launch a deferred-bootstrap client.
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    launchable: Arc<LaunchableTorClient<R>>,
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}
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impl<R: Runtime> RpcSuperuser<R> {
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    /// Construct a new RpcSuperuser object.
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    pub(super) fn new(
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        tor_client: Arc<TorClient<R>>,
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        launchable: Arc<LaunchableTorClient<R>>,
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    ) -> Self {
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        RpcSuperuser {
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            tor_client,
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            launchable,
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        }
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    }
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    /// Ensure that every RPC method is registered for this instantiation of TorClient.
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    ///
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    /// We can't use [`rpc::static_rpc_invoke_fn`] for these, since TorClient is
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    /// parameterized.
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    pub(super) fn rpc_methods() -> Vec<rpc::dispatch::InvokerEnt> {
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        rpc::invoker_ent_list![
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            enter_dormant_mode_on_rpcsuperuser::<R>,
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            bootstrap_client_on_rpcsuperuser::<R>,
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        ]
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    }
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}
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/// Enter "dormant mode".
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///
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/// Currently, the only available dormant mode is "soft dormant mode",
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/// which suspends most background operations until any client request
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/// is received.
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///
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/// Since this method affects all applications using the Arti process,
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/// it requires administrative permissions.
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///
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/// ## Limitations
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///
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/// As of 2026 March, this functionality is not perfectly implemented,
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/// and likely does not interact well with onion services.
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/// Additionally, there are likely background operations that
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/// this operation doesn't cover.
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///
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/// This method returns a reply immediately, but it may take a little
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/// while before all of the background tasks finish their work and stop.
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#[derive(Debug, serde::Deserialize, serde::Serialize, Deftly)]
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#[derive_deftly(rpc::DynMethod)]
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#[deftly(rpc(method_name = "arti:enter_dormant_mode"))]
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struct EnterDormantMode {}
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impl rpc::RpcMethod for EnterDormantMode {
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    type Output = rpc::Nil;
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    type Update = rpc::NoUpdates;
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}
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/// Implementation for [`EnterDormantMode`] on [`RpcSuperuser`].
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async fn enter_dormant_mode_on_rpcsuperuser<R: Runtime>(
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    session: Arc<RpcSuperuser<R>>,
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    _method: Box<EnterDormantMode>,
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    _ctx: Arc<dyn rpc::Context>,
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) -> Result<rpc::Nil, rpc::RpcError> {
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    use arti_client::DormantMode;
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    session.tor_client.set_dormant(DormantMode::Soft);
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    Ok(rpc::Nil::default())
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}
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/// Tell a client to connect to the network and bootstrap itself.
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///
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/// There is no need to invoke this method unless
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/// was started with the `application.defer_bootstrap` option set to true.
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/// By default, clients will automatically connect to the network and bootstrap
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/// themselves.
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///
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/// Since this method affects all applications using the Arti process,
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/// it requires administrative permissions.  We may someday relax this
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/// property.
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#[derive(Debug, serde::Deserialize, serde::Serialize, Deftly)]
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#[derive_deftly(rpc::DynMethod)]
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#[deftly(rpc(method_name = "arti:bootstrap_client"))]
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struct BootstrapClient {}
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impl rpc::RpcMethod for BootstrapClient {
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    type Output = rpc::Nil;
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    type Update = ClientStatusInfo;
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}
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/// Implementation for [`BootstrapClient`] on [`RpcSuperuser`].
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async fn bootstrap_client_on_rpcsuperuser<R: Runtime>(
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    session: Arc<RpcSuperuser<R>>,
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    _method: Box<BootstrapClient>,
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    _ctx: Arc<dyn rpc::Context>,
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    mut updates: rpc::UpdateSink<ClientStatusInfo>,
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) -> Result<rpc::Nil, rpc::RpcError> {
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    let mut events = session.tor_client.bootstrap_events().fuse();
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    // Send the initial status unconditionally.
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    updates
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        .send(session.tor_client.bootstrap_status().into())
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        .await?;
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    let mut bootstrap = Box::pin(session.launchable.bootstrap()).fuse();
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    loop {
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        select_biased! {
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            outcome = bootstrap => {
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                 let () = outcome?;
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                 return Ok(rpc::Nil::default());
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            }
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            e = events.next() => {
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                // (If this returns None, then the `outcome` is about to fail.)
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                if let Some(e) = e {
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                    let status = e.into();
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                    let _ignore_failure = updates.send(status).await;
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                }
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            }
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        };
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    }
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}