fix: listen on circuit relay addresses that contain unsupported segme…

…nts (#1732)

Fixes a bug whereby receiving a circuit relay address would cause js-libp2p to try to listen on the non-relayed parts of the address.  For example if a relay listening on a WebTransport multiaddr was dialled, js-libp2p would then try to listen on the same address due to the relay reservation store calling `transportManager.listen` with the full address.  This would then fail and the relaying would not succeed.

The fix is to call `transportManager.listen` with a multiaddr that just has the peer id and the `p2p-circuit` segments so only the relay transport tries to use the address.

For safety if listening on an address or writing to the peer store fails while creating a relay reservation, remove the reservation from the reservation store to allow us to try again.

Also updates logging to make what is going on a bit clearer.

Closes #1690

---------

Co-authored-by: Chad Nehemiah <[email protected]>

src/circuit-relay/server/index.ts

@@ -287,6 +287,10 @@ class CircuitRelayServer extends EventEmitter<RelayServerEvents> implements Star
     const addrs = []
 
     for (const relayAddr of this.addressManager.getAddresses()) {
+      if (relayAddr.toString().includes('/p2p-circuit')) {
+        continue
+      }
+
       addrs.push(relayAddr.bytes)
     }
 

src/circuit-relay/transport/discovery.ts

@@ -91,7 +91,7 @@ export class RelayDiscovery extends EventEmitter<RelayDiscoveryEvents> implement
     log('searching peer store for relays')
     const peers = (await this.peerStore.all())
       // filter by a list of peers supporting RELAY_V2_HOP and ones we are not listening on
-      .filter(({ id, protocols }) => protocols.includes(RELAY_V2_HOP_CODEC))
+      .filter(({ protocols }) => protocols.includes(RELAY_V2_HOP_CODEC))
       .sort(() => Math.random() - 0.5)
 
     for (const peer of peers) {
@@ -112,11 +112,11 @@ export class RelayDiscovery extends EventEmitter<RelayDiscoveryEvents> implement
           const peerId = provider.id
 
           found++
-          log('found relay peer %p in content routing', peerId)
           await this.peerStore.merge(peerId, {
             multiaddrs: provider.multiaddrs
           })
 
+          log('found relay peer %p in content routing', peerId)
           this.safeDispatchEvent('relay:discover', { detail: peerId })
         }
       }

src/circuit-relay/transport/index.ts

@@ -84,7 +84,6 @@ class CircuitRelayTransport implements Transport {
   private readonly upgrader: Upgrader
   private readonly addressManager: AddressManager
   private readonly connectionGater: ConnectionGater
-  private readonly events: EventEmitter<Libp2pEvents>
   private readonly reservationStore: ReservationStore
   private started: boolean
 
@@ -96,7 +95,6 @@ class CircuitRelayTransport implements Transport {
     this.upgrader = components.upgrader
     this.addressManager = components.addressManager
     this.connectionGater = components.connectionGater
-    this.events = components.events
 
     if (init.discoverRelays != null && init.discoverRelays > 0) {
       this.discovery = new RelayDiscovery(components)
@@ -170,7 +168,7 @@ class CircuitRelayTransport implements Transport {
     const destinationId = destinationAddr.getPeerId()
 
     if (relayId == null || destinationId == null) {
-      const errMsg = 'Circuit relay dial failed as addresses did not have peer id'
+      const errMsg = `Circuit relay dial to ${ma.toString()} failed as address did not have peer ids`
       log.error(errMsg)
       throw new CodeError(errMsg, codes.ERR_RELAYED_DIAL)
     }
@@ -203,7 +201,7 @@ class CircuitRelayTransport implements Transport {
         disconnectOnFailure
       })
     } catch (err: any) {
-      log.error('Circuit relay dial failed', err)
+      log.error(`Circuit relay dial to destination ${destinationPeer.toString()} via relay ${relayPeer.toString()} failed`, err)
       disconnectOnFailure && await relayConnection.close()
       throw err
     }
@@ -244,7 +242,7 @@ class CircuitRelayTransport implements Transport {
       log('new outbound connection %s', maConn.remoteAddr)
       return await this.upgrader.upgradeOutbound(maConn)
     } catch (err) {
-      log.error('Circuit relay dial failed', err)
+      log.error(`Circuit relay dial to destination ${destinationPeer.toString()} via relay ${connection.remotePeer.toString()} failed`, err)
       disconnectOnFailure && await connection.close()
       throw err
     }
@@ -256,8 +254,7 @@ class CircuitRelayTransport implements Transport {
   createListener (options: CreateListenerOptions): Listener {
     return createListener({
       connectionManager: this.connectionManager,
-      relayStore: this.reservationStore,
-      events: this.events
+      relayStore: this.reservationStore
     })
   }
 

src/circuit-relay/transport/listener.ts

@@ -7,79 +7,85 @@ import type { ReservationStore } from './reservation-store.js'
 import type { PeerId } from '@libp2p/interface-peer-id'
 import { PeerMap } from '@libp2p/peer-collections'
 import { logger } from '@libp2p/logger'
-import type { Libp2pEvents } from '@libp2p/interface-libp2p'
+import { peerIdFromString } from '@libp2p/peer-id'
+import type { Connection } from '@libp2p/interface-connection'
+import { CodeError } from '@libp2p/interfaces/errors'
 
 const log = logger('libp2p:circuit-relay:transport:listener')
 
 export interface CircuitRelayTransportListenerComponents {
   connectionManager: ConnectionManager
   relayStore: ReservationStore
-  events: EventEmitter<Libp2pEvents>
 }
 
 class CircuitRelayTransportListener extends EventEmitter<ListenerEvents> implements Listener {
   private readonly connectionManager: ConnectionManager
   private readonly relayStore: ReservationStore
-  private readonly listeningAddrs: PeerMap<Multiaddr>
-  private readonly events: EventEmitter<Libp2pEvents>
+  private readonly listeningAddrs: PeerMap<Multiaddr[]>
 
   constructor (components: CircuitRelayTransportListenerComponents) {
     super()
 
     this.connectionManager = components.connectionManager
     this.relayStore = components.relayStore
-    this.events = components.events
     this.listeningAddrs = new PeerMap()
 
     // remove listening addrs when a relay is removed
     this.relayStore.addEventListener('relay:removed', (evt) => {
       this.#removeRelayPeer(evt.detail)
     })
-
-    // remove listening addrs when a peer disconnects
-    this.events.addEventListener('connection:close', (evt) => {
-      this.#removeRelayPeer(evt.detail.remotePeer)
-    })
   }
 
   async listen (addr: Multiaddr): Promise<void> {
     log('listen on %s', addr)
 
-    const addrString = addr.toString().split('/p2p-circuit').find(a => a !== '')
-    const ma = multiaddr(addrString)
-    const relayConn = await this.connectionManager.openConnection(ma)
+    const relayPeerStr = addr.getPeerId()
+    let relayConn: Connection | undefined
+
+    // check if we already have a connection to the relay
+    if (relayPeerStr != null) {
+      const relayPeer = peerIdFromString(relayPeerStr)
+      const connections = this.connectionManager.getConnectionsMap().get(relayPeer) ?? []
+
+      if (connections.length > 0) {
+        relayConn = connections[0]
+      }
+    }
+
+    // open a new connection as we don't already have one
+    if (relayConn == null) {
+      const addrString = addr.toString().split('/p2p-circuit').find(a => a !== '')
+      const ma = multiaddr(addrString)
+      relayConn = await this.connectionManager.openConnection(ma)
+    }
 
     if (!this.relayStore.hasReservation(relayConn.remotePeer)) {
       // addRelay calls transportManager.listen which calls this listen method
       await this.relayStore.addRelay(relayConn.remotePeer, 'configured')
       return
     }
 
+    const reservation = this.relayStore.getReservation(relayConn.remotePeer)
+
+    if (reservation == null) {
+      throw new CodeError('Did not have reservation after making reservation', 'ERR_NO_RESERVATION')
+    }
+
     if (this.listeningAddrs.has(relayConn.remotePeer)) {
       log('already listening on relay %p', relayConn.remotePeer)
       return
     }
 
-    this.listeningAddrs.set(relayConn.remotePeer, addr)
+    // add all addresses from the relay reservation
+    this.listeningAddrs.set(relayConn.remotePeer, reservation.addrs.map(buf => {
+      return multiaddr(buf).encapsulate('/p2p-circuit')
+    }))
+
     this.safeDispatchEvent('listening', {})
   }
 
-  /**
-   * Get fixed up multiaddrs
-   *
-   * NOTE: This method will grab the peers multiaddrs and expand them such that:
-   *
-   * a) If it's an existing /p2p-circuit address for a specific relay i.e.
-   * `/ip4/0.0.0.0/tcp/0/ipfs/QmRelay/p2p-circuit` this method will expand the
-   * address to `/ip4/0.0.0.0/tcp/0/ipfs/QmRelay/p2p-circuit/ipfs/QmPeer` where
-   * `QmPeer` is this peers id
-   * b) If it's not a /p2p-circuit address, it will encapsulate the address as a /p2p-circuit
-   * addr, such when dialing over a relay with this address, it will create the circuit using
-   * the encapsulated transport address. This is useful when for example, a peer should only
-   * be dialed over TCP rather than any other transport
-   */
   getAddrs (): Multiaddr[] {
-    return [...this.listeningAddrs.values()]
+    return [...this.listeningAddrs.values()].flat()
   }
 
   async close (): Promise<void> {

src/circuit-relay/transport/reservation-store.ts

@@ -96,8 +96,8 @@ export class ReservationStore extends EventEmitter<ReservationStoreEvents> imple
     // When a peer disconnects, if we had a reservation on that peer
     // remove the reservation and multiaddr and maybe trigger search
     // for new relays
-    this.events.addEventListener('connection:close', (evt) => {
-      this.removeRelay(evt.detail.remotePeer)
+    this.events.addEventListener('peer:disconnect', (evt) => {
+      this.#removeRelay(evt.detail)
     })
   }
 
@@ -125,15 +125,15 @@ export class ReservationStore extends EventEmitter<ReservationStoreEvents> imple
    * on the remote peer
    */
   async addRelay (peerId: PeerId, type: RelayType): Promise<void> {
-    log('add relay', this.reserveQueue.size)
+    if (this.peerId.equals(peerId)) {
+      log('not trying to use self as relay')
+      return
+    }
+
+    log('add relay %p', peerId)
 
     await this.reserveQueue.add(async () => {
       try {
-        if (this.peerId.equals(peerId)) {
-          log('not trying to use self as relay')
-          return
-        }
-
         // allow refresh of an existing reservation if it is about to expire
         const existingReservation = this.reservations.get(peerId)
 
@@ -181,6 +181,7 @@ export class ReservationStore extends EventEmitter<ReservationStoreEvents> imple
           })
         }, timeoutDuration)
 
+        // we've managed to create a reservation successfully
         this.reservations.set(peerId, {
           timeout,
           reservation,
@@ -197,13 +198,13 @@ export class ReservationStore extends EventEmitter<ReservationStoreEvents> imple
           }
         })
 
-        await this.transportManager.listen(
-          reservation.addrs.map(ma => {
-            return multiaddr(ma).encapsulate('/p2p-circuit')
-          })
-        )
+        // listen on multiaddr that only the circuit transport is listening for
+        await this.transportManager.listen([multiaddr(`/p2p/${peerId.toString()}/p2p-circuit`)])
       } catch (err) {
         log.error('could not reserve slot on %p', peerId, err)
+
+        // if listening failed, remove the reservation
+        this.reservations.delete(peerId)
       }
     })
   }
@@ -212,6 +213,10 @@ export class ReservationStore extends EventEmitter<ReservationStoreEvents> imple
     return this.reservations.has(peerId)
   }
 
+  getReservation (peerId: PeerId): Reservation | undefined {
+    return this.reservations.get(peerId)?.reservation
+  }
+
   async #createReservation (connection: Connection): Promise<Reservation> {
     log('requesting reservation from %s', connection.remotePeer)
     const stream = await connection.newStream(RELAY_V2_HOP_CODEC)
@@ -243,21 +248,22 @@ export class ReservationStore extends EventEmitter<ReservationStoreEvents> imple
   /**
    * Remove listen relay
    */
-  removeRelay (peerId: PeerId): void {
+  #removeRelay (peerId: PeerId): void {
     const existingReservation = this.reservations.get(peerId)
 
     if (existingReservation == null) {
       return
     }
 
-    log('removing relay %p', peerId)
+    log('connection to relay %p closed, removing reservation from local store', peerId)
 
     clearTimeout(existingReservation.timeout)
     this.reservations.delete(peerId)
 
     this.safeDispatchEvent('relay:removed', { detail: peerId })
 
     if (this.reservations.size < this.maxDiscoveredRelays) {
+      log('not enough relays %d/%d', this.reservations.size, this.maxDiscoveredRelays)
       this.safeDispatchEvent('relay:not-enough-relays', {})
     }
   }