chanmgr: Add identities to pending state in map.

This will let us migrate from `HashMap<Ed25519Identity, Entry>` to
`ByRelayIds<Entry>`.

crates/tor-chanmgr/src/mgr.rs

@@ -12,7 +12,7 @@ use std::result::Result as StdResult;
 use std::sync::Arc;
 use std::time::Duration;
 use tor_error::internal;
-use tor_linkspec::HasRelayIds;
+use tor_linkspec::{HasRelayIds, RelayIds};
 use tor_netdir::params::NetParameters;
 use tor_proto::channel::params::ChannelPaddingInstructionsUpdates;
 
@@ -120,10 +120,13 @@ impl<CF: AbstractChannelFactory> AbstractChanMgr<CF> {
 
     /// Helper: return the objects used to inform pending tasks
     /// about a newly open or failed channel.
-    fn setup_launch<C: Clone>(&self) -> (map::ChannelState<C>, Sending<C>) {
+    fn setup_launch<C: Clone>(&self, ids: RelayIds) -> (map::ChannelState<C>, Sending<C>) {
         let (snd, rcv) = oneshot::channel();
-        let shared = rcv.shared();
-        (map::ChannelState::Building(shared), snd)
+        let pending = rcv.shared();
+        (
+            map::ChannelState::Building(map::PendingEntry { ids, pending }),
+            snd,
+        )
     }
 
     /// Get a channel whose identity is `ident`.
@@ -143,6 +146,8 @@ impl<CF: AbstractChannelFactory> AbstractChanMgr<CF> {
     ) -> Result<(CF::Channel, ChanProvenance)> {
         use ChannelUsage as CU;
 
+        // TODO pt-client: This is not yet used.
+
         let chan = self.get_or_launch_internal(ident, target).await?;
 
         match usage {
@@ -179,6 +184,8 @@ impl<CF: AbstractChannelFactory> AbstractChanMgr<CF> {
         // TODO(nickm): It would be neat to use tor_retry instead.
         let mut last_err = None;
 
+        let ids = RelayIds::from_relay_ids(&target);
+
         for _ in 0..N_ATTEMPTS {
             // First, see what state we're in, and what we should do
             // about it.
@@ -196,19 +203,19 @@ impl<CF: AbstractChannelFactory> AbstractChanMgr<CF> {
                         } else {
                             // Unusable channel.  Move to the Building
                             // state and launch a new channel.
-                            let (newstate, send) = self.setup_launch();
+                            let (newstate, send) = self.setup_launch(ids.clone());
                             let action = Action::Launch(send);
                             (Some(newstate), action)
                         }
                     }
-                    Some(Building(ref pending)) => {
+                    Some(Building(map::PendingEntry { ref pending, .. })) => {
                         let action = Action::Wait(pending.clone());
                         (oldstate, action)
                     }
                     None => {
                         // No channel.  Move to the Building
                         // state and launch a new channel.
-                        let (newstate, send) = self.setup_launch();
+                        let (newstate, send) = self.setup_launch(ids.clone());
                         let action = Action::Launch(send);
                         (Some(newstate), action)
                     }

crates/tor-chanmgr/src/mgr/map.rs

@@ -11,6 +11,8 @@ use std::sync::Arc;
 use tor_cell::chancell::msg::PaddingNegotiate;
 use tor_config::PaddingLevel;
 use tor_error::{internal, into_internal};
+use tor_linkspec::HasRelayIds;
+use tor_linkspec::RelayIds;
 use tor_netdir::{params::NetParameters, params::CHANNEL_PADDING_TIMEOUT_UPPER_BOUND};
 use tor_proto::channel::padding::Parameters as PaddingParameters;
 use tor_proto::channel::padding::ParametersBuilder as PaddingParametersBuilder;
@@ -79,7 +81,7 @@ pub(crate) enum ChannelState<C> {
     /// yielding it to the user.
     Open(OpenEntry<C>),
     /// A channel that's getting built.
-    Building(Pending<C>),
+    Building(PendingEntry<C>),
 }
 
 /// An open channel entry.
@@ -91,6 +93,35 @@ pub(crate) struct OpenEntry<C> {
     pub(crate) max_unused_duration: Duration,
 }
 
+/// An entry for a not-yet-build channel
+#[derive(Clone)]
+pub(crate) struct PendingEntry<C> {
+    /// The keys of the relay to which we're trying to open a channel.
+    pub(crate) ids: RelayIds,
+
+    /// A future we can clone and listen on to learn when this channel attempt
+    /// is successful or failed.
+    ///
+    /// This entry will be removed from the map (and possibly replaced with an
+    /// `OpenEntry`) _before_ this future becomes ready.
+    pub(crate) pending: Pending<C>,
+}
+
+impl<C> HasRelayIds for ChannelState<C>
+where
+    C: HasRelayIds,
+{
+    fn identity(
+        &self,
+        key_type: tor_linkspec::RelayIdType,
+    ) -> Option<tor_linkspec::RelayIdRef<'_>> {
+        match self {
+            ChannelState::Open(OpenEntry { channel, .. }) => channel.identity(key_type),
+            ChannelState::Building(PendingEntry { ids, .. }) => ids.identity(key_type),
+        }
+    }
+}
+
 impl<C: Clone> ChannelState<C> {
     /// Create a new shallow copy of this ChannelState.
     #[cfg(test)]