removed gateway/nym-node using global double spending bloomfilter

common/credential-verification/src/ecash/double_spending.rs

@@ -1,100 +0,0 @@
-// Copyright 2022-2024 - Nym Technologies SA <contact@nymtech.net>
-// SPDX-License-Identifier: GPL-3.0-only
-
-use crate::ecash::error::EcashTicketError;
-use crate::ecash::state::SharedState;
-use nym_ecash_double_spending::DoubleSpendingFilter;
-use nym_gateway_storage::Storage;
-use nym_task::TaskClient;
-use nym_validator_client::client::NymApiClientExt;
-use nym_validator_client::EcashApiClient;
-use rand::prelude::SliceRandom;
-use rand::thread_rng;
-use std::sync::Arc;
-use tokio::sync::{RwLock, RwLockReadGuard};
-use tokio::time::{interval, Duration};
-use tracing::{info, trace, warn};
-
-#[derive(Clone)]
-pub(crate) struct DoubleSpendingDetector<S> {
-    spent_serial_numbers: Arc<RwLock<DoubleSpendingFilter>>,
-    shared_state: SharedState<S>,
-}
-
-impl<S> DoubleSpendingDetector<S>
-where
-    S: Storage + Clone + Send + Sync + 'static,
-{
-    pub(crate) fn new(shared_state: SharedState<S>) -> Self {
-        DoubleSpendingDetector {
-            spent_serial_numbers: Arc::new(RwLock::new(DoubleSpendingFilter::new_empty_ecash())),
-            shared_state,
-        }
-    }
-
-    pub(crate) async fn check(&self, serial_number: &Vec<u8>) -> bool {
-        self.spent_serial_numbers.read().await.check(serial_number)
-    }
-
-    async fn latest_api_endpoints(
-        &self,
-    ) -> Result<RwLockReadGuard<Vec<EcashApiClient>>, EcashTicketError> {
-        let epoch_id = self.shared_state.current_epoch_id().await?;
-        self.shared_state.api_clients(epoch_id).await
-    }
-
-    async fn refresh_bloomfilter(&self) {
-        let mut filter_builder = self.spent_serial_numbers.read().await.rebuild();
-
-        let api_clients = match self.latest_api_endpoints().await {
-            Ok(clients) => clients,
-            Err(err) => {
-                warn!("failed to obtain current api clients: {err}");
-                return;
-            }
-        };
-
-        let mut clients = api_clients
-            .iter()
-            .map(|c| c.api_client.clone())
-            .collect::<Vec<_>>();
-        clients.shuffle(&mut thread_rng());
-
-        for client in clients {
-            match client.nym_api.double_spending_filter_v1().await {
-                Ok(response) => {
-                    // due to relative big size of the filter, query only one api since all of them should contain
-                    // roughly the same data anyway.
-                    filter_builder.add_bytes(&response.bitmap);
-                    *self.spent_serial_numbers.write().await = filter_builder.build();
-                    return;
-                }
-                Err(err) => {
-                    warn!("Validator @ {} could not be reached. There might be a problem with the ecash endpoint: {err}", client.api_url());
-                }
-            }
-        }
-
-        warn!("none of the validators could be reached. the bloomfilter will remain unchanged.");
-    }
-
-    async fn run(&self, mut shutdown: TaskClient) {
-        info!("Starting Ecash DoubleSpendingDetector");
-        let mut interval = interval(Duration::from_secs(600));
-
-        while !shutdown.is_shutdown() {
-            tokio::select! {
-                biased;
-                _ = shutdown.recv() => {
-                    trace!("ecash_verifier::DoubleSpendingDetector : received shutdown");
-                },
-                _ = interval.tick() => self.refresh_bloomfilter().await,
-
-            }
-        }
-    }
-
-    pub(crate) fn start(self, shutdown: nym_task::TaskClient) {
-        tokio::spawn(async move { self.run(shutdown).await });
-    }
-}

common/credential-verification/src/ecash/mod.rs

@@ -4,7 +4,6 @@
 use crate::Error;
 use credential_sender::CredentialHandler;
 use credential_sender::CredentialHandlerConfig;
-use double_spending::DoubleSpendingDetector;
 use error::EcashTicketError;
 use futures::channel::mpsc::{self, UnboundedSender};
 use nym_credentials::CredentialSpendingData;
@@ -18,7 +17,6 @@ use tokio::sync::{Mutex, RwLockReadGuard};
 use tracing::error;
 
 pub mod credential_sender;
-pub(crate) mod double_spending;
 pub mod error;
 mod helpers;
 mod state;
@@ -31,7 +29,6 @@ pub struct EcashManager<S> {
     pk_bytes: [u8; 32], // bytes representation of a pub key representing the verifier
     pay_infos: Mutex<Vec<NymPayInfo>>,
     cred_sender: UnboundedSender<ClientTicket>,
-    double_spend_detector: DoubleSpendingDetector<S>,
 }
 
 impl<S> EcashManager<S>
@@ -47,9 +44,6 @@ where
     ) -> Result<Self, Error> {
         let shared_state = SharedState::new(nyxd_client, storage).await?;
 
-        let double_spend_detector = DoubleSpendingDetector::new(shared_state.clone());
-        double_spend_detector.clone().start(shutdown.clone());
-
         let (cred_sender, cred_receiver) = mpsc::unbounded();
 
         let cs =
@@ -62,7 +56,6 @@ where
             pk_bytes,
             pay_infos: Default::default(),
             cred_sender,
-            double_spend_detector,
         })
     }
 
@@ -163,10 +156,6 @@ where
         Ok(())
     }
 
-    pub async fn check_double_spend(&self, serial_number: &Vec<u8>) -> bool {
-        self.double_spend_detector.check(serial_number).await
-    }
-
     pub fn async_verify(&self, ticket: ClientTicket) {
         // TODO: I guess do something for shutdowns
         let _ = self

common/credential-verification/src/lib.rs

@@ -53,18 +53,6 @@ impl<S: Storage + Clone + 'static> CredentialVerifier<S> {
         Ok(())
     }
 
-    async fn check_bloomfilter(&self, serial_number: &Vec<u8>) -> Result<()> {
-        trace!("checking the bloomfilter...");
-
-        let spent = self.ecash_verifier.check_double_spend(serial_number).await;
-
-        if spent {
-            trace!("the credential has already been spent before at some gateway before (bloomfilter failure)");
-            return Err(Error::BandwidthCredentialAlreadySpent);
-        }
-        Ok(())
-    }
-
     async fn check_local_db_for_double_spending(&self, serial_number: &[u8]) -> Result<()> {
         trace!("checking local db for double spending...");
 
@@ -128,7 +116,6 @@ impl<S: Storage + Clone + 'static> CredentialVerifier<S> {
         }
 
         self.check_credential_spending_date(spend_date.ecash_date())?;
-        self.check_bloomfilter(&serial_number).await?;
         self.check_local_db_for_double_spending(&serial_number)
             .await?;