Additional check when ensuring wallet synchronised between chains

pkg/chain/ethereum/tbtc.go

@@ -2026,7 +2026,7 @@ func (tc *TbtcChain) GetMovingFundsParameters() (
 func (tc *TbtcChain) GetMovedFundsSweepRequest(
 	movingFundsTxHash bitcoin.Hash,
 	movingFundsTxOutpointIndex uint32,
-) (*tbtc.MovedFundsSweepRequest, error) {
+) (*tbtc.MovedFundsSweepRequest, bool, error) {
 	movedFundsKey := buildMovedFundsKey(
 		movingFundsTxHash,
 		movingFundsTxOutpointIndex,
@@ -2036,16 +2036,21 @@ func (tc *TbtcChain) GetMovedFundsSweepRequest(
 		movedFundsKey,
 	)
 	if err != nil {
-		return nil, fmt.Errorf(
+		return nil, false, fmt.Errorf(
 			"cannot get moved funds sweep request for key [0x%x]: [%v]",
 			movedFundsKey.Text(16),
 			err,
 		)
 	}
 
+	// Moved funds sweep request not found.
+	if movedFundsSweepRequest.CreatedAt == 0 {
+		return nil, false, nil
+	}
+
 	state, err := parseMovedFundsSweepRequestState(movedFundsSweepRequest.State)
 	if err != nil {
-		return nil, fmt.Errorf(
+		return nil, false, fmt.Errorf(
 			"cannot parse state for moved funds sweep request [0x%x]: [%v]",
 			movedFundsKey.Text(16),
 			err,
@@ -2057,7 +2062,7 @@ func (tc *TbtcChain) GetMovedFundsSweepRequest(
 		Value:               movedFundsSweepRequest.Value,
 		CreatedAt:           time.Unix(int64(movedFundsSweepRequest.CreatedAt), 0),
 		State:               state,
-	}, nil
+	}, true, nil
 }
 
 func parseMovedFundsSweepRequestState(value uint8) (

pkg/maintainer/spv/chain.go

@@ -21,14 +21,8 @@ type Chain interface {
 	) error
 
 	// GetDepositRequest gets the on-chain deposit request for the given
-	// funding transaction hash and output index.The returned values represent:
-	// - deposit request which is non-nil only when the deposit request was
-	//   found,
-	// - boolean value which is true if the deposit request was found, false
-	//   otherwise,
-	// - error which is non-nil only when the function execution failed. It will
-	//   be nil if the deposit request was not found, but the function execution
-	//   succeeded.
+	// funding transaction hash and output index. The returned bool value
+	// indicates whether the request was found or not.
 	GetDepositRequest(
 		fundingTxHash bitcoin.Hash,
 		fundingOutputIndex uint32,
@@ -59,10 +53,11 @@ type Chain interface {
 
 	// GetMovedFundsSweepRequest gets the on-chain moved funds sweep request for
 	// the given moving funds transaction hash and output index.
+	// The returned bool value indicates whether the request was found or not.
 	GetMovedFundsSweepRequest(
 		movingFundsTxHash bitcoin.Hash,
 		movingFundsTxOutpointIndex uint32,
-	) (*tbtc.MovedFundsSweepRequest, error)
+	) (*tbtc.MovedFundsSweepRequest, bool, error)
 
 	// SubmitRedemptionProofWithReimbursement submits the redemption proof
 	// via MaintainerProxy. The caller is reimbursed.

pkg/maintainer/spv/chain_test.go

@@ -666,7 +666,7 @@ func (lc *localChain) setMovedFundsSweepRequest(
 func (lc *localChain) GetMovedFundsSweepRequest(
 	movingFundsTxHash bitcoin.Hash,
 	movingFundsTxOutpointIndex uint32,
-) (*tbtc.MovedFundsSweepRequest, error) {
+) (*tbtc.MovedFundsSweepRequest, bool, error) {
 	lc.mutex.Lock()
 	defer lc.mutex.Unlock()
 
@@ -677,10 +677,10 @@ func (lc *localChain) GetMovedFundsSweepRequest(
 
 	request, ok := lc.movedFundsSweepRequests[requestKey]
 	if !ok {
-		return nil, fmt.Errorf("request not found")
+		return nil, false, nil
 	}
 
-	return request, nil
+	return request, true, nil
 }
 
 type mockBlockCounter struct {

pkg/maintainer/spv/moved_funds_sweep.go

@@ -275,7 +275,7 @@ func isUnprovenMovedFundsSweepTransaction(
 	requestTransactionHash := transaction.Inputs[0].Outpoint.TransactionHash
 	requestOutputIndex := transaction.Inputs[0].Outpoint.OutputIndex
 
-	movedFundsSweepRequest, err := spvChain.GetMovedFundsSweepRequest(
+	movedFundsSweepRequest, isRequest, err := spvChain.GetMovedFundsSweepRequest(
 		requestTransactionHash,
 		requestOutputIndex,
 	)
@@ -286,6 +286,12 @@ func isUnprovenMovedFundsSweepTransaction(
 		)
 	}
 
+	// Check if it's a moved funds sweep request at all.
+	if !isRequest {
+		return false, nil
+	}
+
+	// Check if it's a pending moved funds sweep request.
 	if movedFundsSweepRequest.State != tbtc.MovedFundsStatePending {
 		return false, nil
 	}

pkg/tbtc/chain.go

@@ -209,18 +209,20 @@ type BridgeChain interface {
 	) (*RedemptionRequest, bool, error)
 
 	// GetDepositRequest gets the on-chain deposit request for the given
-	// funding transaction hash and output index.The returned values represent:
-	// - deposit request which is non-nil only when the deposit request was
-	//   found,
-	// - boolean value which is true if the deposit request was found, false
-	//   otherwise,
-	// - error which is non-nil only when the function execution failed. It will
-	//   be nil if the deposit request was not found, but the function execution
-	//   succeeded.
+	// funding transaction hash and output index. The returned bool value
+	// indicates whether the request was found or not.
 	GetDepositRequest(
 		fundingTxHash bitcoin.Hash,
 		fundingOutputIndex uint32,
 	) (*DepositChainRequest, bool, error)
+
+	// GetMovedFundsSweepRequest gets the on-chain moved funds sweep request for
+	// the given moving funds transaction hash and output index.
+	// The returned bool value indicates whether the request was found or not.
+	GetMovedFundsSweepRequest(
+		movingFundsTxHash bitcoin.Hash,
+		movingFundsTxOutpointIndex uint32,
+	) (*MovedFundsSweepRequest, bool, error)
 }
 
 // NewWalletRegisteredEvent represents a new wallet registered event.

pkg/tbtc/chain_test.go

@@ -202,6 +202,13 @@ func (lc *localChain) IsBetaOperator() (bool, error) {
 	panic("unsupported")
 }
 
+func (lc *localChain) GetMovedFundsSweepRequest(
+	movingFundsTxHash bitcoin.Hash,
+	movingFundsTxOutpointIndex uint32,
+) (*MovedFundsSweepRequest, bool, error) {
+	panic("unsupported")
+}
+
 func (lc *localChain) GetOperatorID(
 	operatorAddress chain.Address,
 ) (chain.OperatorID, error) {

pkg/tbtc/wallet.go

@@ -7,11 +7,12 @@ import (
 	"crypto/elliptic"
 	"encoding/hex"
 	"fmt"
-	"golang.org/x/exp/slices"
 	"math/big"
 	"sync"
 	"time"
 
+	"golang.org/x/exp/slices"
+
 	"github.com/ipfs/go-log/v2"
 	"github.com/keep-network/keep-core/pkg/bitcoin"
 	"github.com/keep-network/keep-core/pkg/chain"
@@ -579,8 +580,15 @@ func EnsureWalletSyncedBetweenChains(
 		}
 
 		for _, utxo := range allUtxos {
-			// We know that valid first transaction of the wallet always
-			// have just one output. Any utxos with output index other
+			// The first valid transaction of a wallet is most likely a deposit
+			// sweep, but there is a small chance it could be a moved funds sweep.
+			// It could happen if the wallet was selected as a target wallet and
+			// some funds were moved to it by the source wallet. In that case the
+			// wallet could create a moved fund sweep transaction even before
+			// sweeping any deposits.
+
+			// In any case, we know that valid first transaction of the wallet
+			// always have just one output. Any utxos with output index other
 			// than 0 are certainly not produced by the wallet and, we should
 			// not take them into account.
 			if utxo.Outpoint.OutputIndex != 0 {
@@ -596,11 +604,10 @@ func EnsureWalletSyncedBetweenChains(
 				)
 			}
 
-			// We know that valid first transaction of the wallet have all their
-			// inputs referring to revealed deposits. We need to check just
-			// one input. If it points to a revealed deposit, that means
-			// the given transaction is produced by our wallet. Otherwise,
-			// such a transaction is a spam.
+			// The transaction could be a deposit sweep. In that case all the
+			// transaction's inputs must refer to revealed deposits. We can
+			// check one input. If it points to a revealed deposit, that means
+			// the given transaction is produced by our wallet.
 			input := transaction.Inputs[0]
 			_, isDeposit, err := bridgeChain.GetDepositRequest(
 				input.Outpoint.TransactionHash,
@@ -617,11 +624,40 @@ func EnsureWalletSyncedBetweenChains(
 			}
 
 			if isDeposit {
-				// If that's the case, the wallet was already done their
-				// first Bitcoin transaction and the Bridge is awaiting the
-				// SPV proof.
+				// If that's the case, the wallet has already created a deposit
+				// sweep as their first Bitcoin transaction and the Bridge is
+				// awaiting the SPV proof.
+				return fmt.Errorf("wallet already produced their first " +
+					"Bitcoin transaction (deposit sweep); Bridge is probably " +
+					"awaiting the SPV proof",
+				)
+			}
+
+			// The transaction could be a moved funds sweep request. In that
+			// case the transaction's input must refer to a moved funds sweep
+			// request. If the input points to a moved funds sweep request, that
+			// means the given transaction is produced by our wallet.
+			_, isRequest, err := bridgeChain.GetMovedFundsSweepRequest(
+				input.Outpoint.TransactionHash,
+				input.Outpoint.OutputIndex,
+			)
+			if err != nil {
+				return fmt.Errorf(
+					"cannot get moved funds sweep request for hash [%s] "+
+						"and output index [%v]: [%v]",
+					input.Outpoint.TransactionHash.String(),
+					input.Outpoint.OutputIndex,
+					err,
+				)
+			}
+
+			if isRequest {
+				// If that's the case, the wallet has already created a moved
+				// funds sweep as their first Bitcoin transaction and the Bridge
+				// is awaiting the SPV proof.
 				return fmt.Errorf("wallet already produced their first " +
-					"Bitcoin transaction; Bridge is probably awaiting the SPV proof",
+					"Bitcoin transaction (moved funds sweep); Bridge is " +
+					"probably awaiting the SPV proof",
 				)
 			}
 

pkg/tbtcpg/chain.go

@@ -148,13 +148,6 @@ type Chain interface {
 		err error,
 	)
 
-	// GetMovedFundsSweepRequest gets the on-chain moved funds sweep request for
-	// the given moving funds transaction hash and output index.
-	GetMovedFundsSweepRequest(
-		movingFundsTxHash bitcoin.Hash,
-		movingFundsTxOutpointIndex uint32,
-	) (*tbtc.MovedFundsSweepRequest, error)
-
 	// PastMovingFundsCommitmentSubmittedEvents fetches past moving funds
 	// commitment submitted events according to the provided filter or
 	// unfiltered if the filter is nil. Returned events are sorted by the block

pkg/tbtcpg/chain_test.go

@@ -770,7 +770,7 @@ func (lc *LocalChain) GetMovingFundsParameters() (
 func (lc *LocalChain) GetMovedFundsSweepRequest(
 	movingFundsTxHash bitcoin.Hash,
 	movingFundsTxOutpointIndex uint32,
-) (*tbtc.MovedFundsSweepRequest, error) {
+) (*tbtc.MovedFundsSweepRequest, bool, error) {
 	lc.mutex.Lock()
 	defer lc.mutex.Unlock()
 
@@ -781,10 +781,10 @@ func (lc *LocalChain) GetMovedFundsSweepRequest(
 
 	request, ok := lc.movedFundsSweepRequests[requestKey]
 	if !ok {
-		return nil, fmt.Errorf("request not found")
+		return nil, false, nil
 	}
 
-	return request, nil
+	return request, true, nil
 }
 
 func (lc *LocalChain) SetMovedFundsSweepRequest(

pkg/tbtcpg/moved_funds_sweep.go

@@ -174,7 +174,7 @@ func (mfst *MovedFundsSweepTask) FindMovingFundsTxData(
 	// Find the first outpoint that represents an unproven moved funds sweep
 	// request and return it.
 	for _, outpoint := range movingFundsTxOutpoints {
-		movedFundsSweepRequest, err := mfst.chain.GetMovedFundsSweepRequest(
+		movedFundsSweepRequest, isRequest, err := mfst.chain.GetMovedFundsSweepRequest(
 			outpoint.TransactionHash,
 			outpoint.OutputIndex,
 		)
@@ -185,6 +185,12 @@ func (mfst *MovedFundsSweepTask) FindMovingFundsTxData(
 			)
 		}
 
+		// Check just in case. It should not happen, as all the outpoint should
+		// represent a valid request.
+		if !isRequest {
+			continue
+		}
+
 		if movedFundsSweepRequest.State == tbtc.MovedFundsStatePending {
 			return outpoint.TransactionHash, outpoint.OutputIndex, nil
 		}