1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123
// Copyright 2019, The Tari Project // // Redistribution and use in source and binary forms, with or without modification, are permitted provided that the // following conditions are met: // // 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following // disclaimer. // // 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the // following disclaimer in the documentation and/or other materials provided with the distribution. // // 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote // products derived from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, // INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, // WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE // USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. use crate::{discovery::DhtDiscoveryError, envelope::NodeDestination, proto::dht::DiscoveryResponseMessage}; use futures::{ channel::{mpsc, oneshot}, SinkExt, }; use std::{ fmt::{Display, Error, Formatter}, time::Duration, }; use tari_comms::{peer_manager::Peer, types::CommsPublicKey}; use tokio::time; #[derive(Debug)] pub enum DhtDiscoveryRequest { DiscoverPeer( Box<CommsPublicKey>, NodeDestination, oneshot::Sender<Result<Peer, DhtDiscoveryError>>, ), NotifyDiscoveryResponseReceived(Box<DiscoveryResponseMessage>), } impl Display for DhtDiscoveryRequest { fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> { use DhtDiscoveryRequest::*; match self { DiscoverPeer(public_key, dest, _) => write!(f, "DiscoverPeer({}, {})", public_key, dest), NotifyDiscoveryResponseReceived(discovery_resp) => { write!(f, "NotifyDiscoveryResponseReceived({:#?})", discovery_resp) }, } } } #[derive(Clone)] pub struct DhtDiscoveryRequester { sender: mpsc::Sender<DhtDiscoveryRequest>, discovery_timeout: Duration, } impl DhtDiscoveryRequester { pub fn new(sender: mpsc::Sender<DhtDiscoveryRequest>, discovery_timeout: Duration) -> Self { Self { sender, discovery_timeout, } } /// Initiate a peer discovery /// /// ## Arguments /// - `dest_public_key` - The public key of he recipient used to create a shared ECDH key which in turn is used to /// encrypt the discovery message /// - `destination` - The `NodeDestination` to use in the DhtHeader when sending a discovery message. /// - `Unknown` destination will maintain complete privacy, the trade off is that discovery needs to propagate /// the entire network to reach the destination and so may take longer /// - `NodeId` Instruct propagation nodes to direct the message to peers closer to the given NodeId. The `NodeId` /// may be directed to a region close to the real destination (somewhat private) or directed at a particular /// node (not private) /// - `PublicKey` if any node on the network knows this public key, the message will be directed to that node. /// This sacrifices privacy for more efficient discovery in terms of network bandwidth and may result in /// quicker discovery times. pub async fn discover_peer( &mut self, dest_public_key: Box<CommsPublicKey>, destination: NodeDestination, ) -> Result<Peer, DhtDiscoveryError> { let (reply_tx, reply_rx) = oneshot::channel(); self.sender .send(DhtDiscoveryRequest::DiscoverPeer( dest_public_key, destination, reply_tx, )) .await?; time::timeout( self.discovery_timeout, reply_rx ) .await // Timeout? .map_err(|_| DhtDiscoveryError::DiscoveryTimeout)? // Channel error? .map_err(|_| DhtDiscoveryError::ReplyCanceled)? } pub async fn notify_discovery_response_received( &mut self, response: DiscoveryResponseMessage, ) -> Result<(), DhtDiscoveryError> { self.sender .send(DhtDiscoveryRequest::NotifyDiscoveryResponseReceived(Box::new(response))) .await?; Ok(()) } }