From 7e4c59a0a381fda5926cbd0a554c26330ba7de11 Mon Sep 17 00:00:00 2001
From: Luke Parker <lukeparker5132@gmail.com>
Date: Fri, 20 Sep 2024 01:24:28 -0400
Subject: [PATCH] Have the Router track its deployment block

Prevents a consensus split where some nodes would drop transfers if their node
didn't think the Router was deployed, and some would handle them.
---
 .../ethereum/router/contracts/Router.sol      |  9 ++++++++
 processor/ethereum/router/src/lib.rs          | 21 +++++++++++++++++--
 processor/ethereum/src/rpc.rs                 | 12 +++++++++--
 3 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/processor/ethereum/router/contracts/Router.sol b/processor/ethereum/router/contracts/Router.sol
index 9100f59e..d82c0d90 100644
--- a/processor/ethereum/router/contracts/Router.sol
+++ b/processor/ethereum/router/contracts/Router.sol
@@ -7,6 +7,9 @@ import "Schnorr.sol";
 
 // _ is used as a prefix for internal functions and smart-contract-scoped variables
 contract Router {
+  // The block at which this contract was deployed.
+  uint256 private _deploymentBlock;
+
   // Nonce is incremented for each command executed, preventing replays
   uint256 private _nonce;
 
@@ -63,6 +66,8 @@ contract Router {
   }
 
   constructor(bytes32 initialSeraiKey) _updateSeraiKeyAtEndOfFn(0, initialSeraiKey) {
+    _deploymentBlock = block.number;
+
     // We consumed nonce 0 when setting the initial Serai key
     _nonce = 1;
     // Nonces are incremented by 1 upon account creation, prior to any code execution, per EIP-161
@@ -230,6 +235,10 @@ contract Router {
     return _nonce;
   }
 
+  function deploymentBlock() external view returns (uint256) {
+    return _deploymentBlock;
+  }
+
   function smartContractNonce() external view returns (uint256) {
     return _smartContractNonce;
   }
diff --git a/processor/ethereum/router/src/lib.rs b/processor/ethereum/router/src/lib.rs
index 248523b8..d78b3218 100644
--- a/processor/ethereum/router/src/lib.rs
+++ b/processor/ethereum/router/src/lib.rs
@@ -11,7 +11,7 @@ use alloy_consensus::TxLegacy;
 
 use alloy_sol_types::{SolValue, SolConstructor, SolCall, SolEvent};
 
-use alloy_rpc_types_eth::Filter;
+use alloy_rpc_types_eth::{TransactionInput, TransactionRequest, Filter};
 use alloy_transport::{TransportErrorKind, RpcError};
 use alloy_simple_request_transport::SimpleRequest;
 use alloy_provider::{Provider, RootProvider};
@@ -296,6 +296,23 @@ impl Router {
     self.1
   }
 
+  /// Fetch the block this contract was deployed at.
+  pub async fn deployment_block(&self) -> Result<u64, RpcError<TransportErrorKind>> {
+    let call = TransactionRequest::default()
+      .to(self.address())
+      .input(TransactionInput::new(abi::deploymentBlockCall::new(()).abi_encode().into()));
+    let bytes = self.0.call(&call).await?;
+    let deployment_block = abi::deploymentBlockCall::abi_decode_returns(&bytes, true)
+      .map_err(|e| {
+        TransportErrorKind::Custom(
+          format!("node returned a non-u256 for function returning u256: {e:?}").into(),
+        )
+      })?
+      ._0;
+
+    Ok(deployment_block.try_into().unwrap())
+  }
+
   /// Get the message to be signed in order to update the key for Serai.
   pub fn update_serai_key_message(chain_id: U256, nonce: u64, key: &PublicKey) -> Vec<u8> {
     (
@@ -420,7 +437,7 @@ impl Router {
         */
         if let Some(matched) = Erc20::match_top_level_transfer(&self.0, tx_hash, self.1).await? {
           // Mark this log index as used so it isn't used again
-          transfer_check.insert(matched.log_index);
+          transfer_check.insert(matched.id.1);
         }
 
         // Find a matching transfer log
diff --git a/processor/ethereum/src/rpc.rs b/processor/ethereum/src/rpc.rs
index 1eaa4988..a5533484 100644
--- a/processor/ethereum/src/rpc.rs
+++ b/processor/ethereum/src/rpc.rs
@@ -156,10 +156,12 @@ impl<D: Db> ScannerFeed for Rpc<D> {
         // The Router wasn't deployed yet so we cannot have any on-chain interactions
         // If the Router has been deployed by the block we've synced to, it won't have any events
         // for these blocks anways, so this doesn't risk a consensus split
-        // TODO: This does as we can have top-level transfers to the router before it's deployed
         return Ok(FullEpoch { epoch, instructions, executed });
       };
 
+      let router_deployment_block = router.deployment_block().await?;
+
+      // TODO: Use a LocalSet and handle all these in parallel
       let mut to_check = epoch.end_hash;
       while to_check != epoch.prior_end_hash {
         let to_check_block = self
@@ -177,6 +179,12 @@ impl<D: Db> ScannerFeed for Rpc<D> {
           })?
           .header;
 
+        // If this is before the Router was deployed, move on
+        if to_check_block.number < router_deployment_block {
+          // This is sa
+          break;
+        }
+
         instructions.append(
           &mut router.in_instructions(to_check_block.number, &HashSet::from(TOKENS)).await?,
         );
@@ -187,7 +195,7 @@ impl<D: Db> ScannerFeed for Rpc<D> {
               .await?
           {
             instructions.push(EthereumInInstruction {
-              id: (id, u64::MAX),
+              id,
               from,
               coin: EthereumCoin::Erc20(token),
               amount,