Support share bundle cancellations

go.mod

@@ -5,7 +5,7 @@ go 1.22
 require (
 	github.com/VictoriaMetrics/metrics v1.35.1
 	github.com/ethereum/go-ethereum v1.14.10
-	github.com/flashbots/go-utils v0.8.1-0.20241030134403-501d395be6a9
+	github.com/flashbots/go-utils v0.8.1-0.20241104120502-7337c4b9d7b6
 	github.com/google/uuid v1.6.0
 	github.com/hashicorp/golang-lru/v2 v2.0.7
 	github.com/stretchr/testify v1.9.0

go.sum

@@ -54,8 +54,8 @@ github.com/ethereum/go-ethereum v1.14.10 h1:kC24WjYeRjDy86LVo6MfF5Xs7nnUu+XG4Aja
 github.com/ethereum/go-ethereum v1.14.10/go.mod h1:+l/fr42Mma+xBnhefL/+z11/hcmJ2egl+ScIVPjhc7E=
 github.com/ethereum/go-verkle v0.1.1-0.20240829091221-dffa7562dbe9 h1:8NfxH2iXvJ60YRB8ChToFTUzl8awsc3cJ8CbLjGIl/A=
 github.com/ethereum/go-verkle v0.1.1-0.20240829091221-dffa7562dbe9/go.mod h1:M3b90YRnzqKyyzBEWJGqj8Qff4IDeXnzFw0P9bFw3uk=
-github.com/flashbots/go-utils v0.8.1-0.20241030134403-501d395be6a9 h1:n0Xl5xg08GubAZRy/6aF7rBiyiSYpGlHoRiz957yWPg=
-github.com/flashbots/go-utils v0.8.1-0.20241030134403-501d395be6a9/go.mod h1:Lo/nrlC+q8ANgT3e6MKALIJCU+V9qTSgNtoLk/q1uIw=
+github.com/flashbots/go-utils v0.8.1-0.20241104120502-7337c4b9d7b6 h1:CYI4xzd3ho4p9tjm4j9vOKHOqes2zz0mSsgUXZVwUJ8=
+github.com/flashbots/go-utils v0.8.1-0.20241104120502-7337c4b9d7b6/go.mod h1:Lo/nrlC+q8ANgT3e6MKALIJCU+V9qTSgNtoLk/q1uIw=
 github.com/getsentry/sentry-go v0.27.0 h1:Pv98CIbtB3LkMWmXi4Joa5OOcwbmnX88sF5qbK3r3Ps=
 github.com/getsentry/sentry-go v0.27.0/go.mod h1:lc76E2QywIyW8WuBnwl8Lc4bkmQH4+w1gwTf25trprY=
 github.com/go-ole/go-ole v1.2.5/go.mod h1:pprOEPIfldk/42T2oK7lQ4v4JSDwmV0As9GaiUsvbm0=

proxy/api.go

@@ -29,6 +29,8 @@ var (
 	errSubsidyWrongEndpoint = errors.New("subsidy can only be called on public method")
 	errSubsidyWrongCaller   = errors.New("subsidy can only be called by Flashbots")
 
+	errUUIDParse = errors.New("failed to parse UUID")
+
 	apiNow = time.Now
 )
 
@@ -146,7 +148,6 @@ func (prx *ReceiverProxy) MevSendBundle(ctx context.Context, mevSendBundle rpcty
 		return err
 	}
 
-	// TODO: make sure that cancellations are handled by the builder properly
 	err = ValidateMevSendBundle(&mevSendBundle, publicEndpoint)
 	if err != nil {
 		return err
@@ -156,8 +157,33 @@ func (prx *ReceiverProxy) MevSendBundle(ctx context.Context, mevSendBundle rpcty
 		mevSendBundle.Metadata = &rpctypes.MevBundleMetadata{
 			Signer: &parsedRequest.signer,
 		}
+		if mevSendBundle.ReplacementUUID != "" {
+			replUUID, err := uuid.Parse(mevSendBundle.ReplacementUUID)
+			if err != nil {
+				return errors.Join(errUUIDParse, err)
+			}
+			replacementKey := replacementNonceKey{
+				uuid:   replUUID,
+				signer: parsedRequest.signer,
+			}
+			// this is not atomic but the normal user will not send multiple replacements in parallel
+			nonce, ok := prx.replacementNonceRLU.Peek(replacementKey)
+			if ok {
+				nonce += 1
+			} else {
+				nonce = 0
+			}
+			prx.replacementNonceRLU.Add(replacementKey, nonce)
+			mevSendBundle.Metadata.ReplacementNonce = &nonce
+
+			if len(mevSendBundle.Body) == 0 {
+				cancelled := true
+				mevSendBundle.Metadata.Cancelled = &cancelled
+			}
+		}
 	}
 
+	// @note: unique key filterst same requests and it can interact with cancellations (you can't cancel multiple times per block)
 	uniqueKey := mevSendBundle.UniqueKey()
 	parsedRequest.requestArgUniqueKey = &uniqueKey
 

proxy/api_validate.go

@@ -15,6 +15,8 @@ var (
 	errRefundPercent    = errors.New("refund percent field should not be set")
 	errRefundRecipient  = errors.New("refund recipient field should not be set")
 	errRefundTxHashes   = errors.New("refund tx hashes field should not be set")
+
+	errLocalEndpointSbundleMetadata = errors.New("mev share bundle should not containt metadata when sent to local endpoint")
 )
 
 func ValidateEthSendBundle(args *rpctypes.EthSendBundleArgs, publicEndpoint bool) error {
@@ -54,8 +56,18 @@ func ValidateEthCancelBundle(args *rpctypes.EthCancelBundleArgs, publicEndpoint
 	return nil
 }
 
-func ValidateMevSendBundle(args *rpctypes.MevSendBundleArgs, _ bool) error {
+func ValidateMevSendBundle(args *rpctypes.MevSendBundleArgs, publicEndpoint bool) error {
 	// @perf it calculates hash
 	_, err := args.Validate()
-	return err
+	if err != nil {
+		return err
+	}
+
+	if !publicEndpoint {
+		if args.Metadata != nil {
+			return errLocalEndpointSbundleMetadata
+		}
+	}
+
+	return nil
 }

proxy/proxy.go

@@ -20,8 +20,16 @@ var (
 	requestsRLUTTL  = time.Second * 12
 
 	peerUpdateTime = time.Minute * 5
+
+	replacementNonceSize = 4096
+	replacementNonceTTL  = time.Second * 5 * 12
 )
 
+type replacementNonceKey struct {
+	uuid   uuid.UUID
+	signer common.Address
+}
+
 type ReceiverProxy struct {
 	ReceiverProxyConstantConfig
 
@@ -48,6 +56,8 @@ type ReceiverProxy struct {
 
 	requestUniqueKeysRLU *expirable.LRU[uuid.UUID, struct{}]
 
+	replacementNonceRLU *expirable.LRU[replacementNonceKey, int]
+
 	peerUpdaterClose chan struct{}
 }
 
@@ -98,6 +108,7 @@ func NewReceiverProxy(config ReceiverProxyConfig) (*ReceiverProxy, error) {
 		Certificate:                 certificate,
 		localBuilder:                localBuilder,
 		requestUniqueKeysRLU:        expirable.NewLRU[uuid.UUID, struct{}](requestsRLUSize, nil, requestsRLUTTL),
+		replacementNonceRLU:         expirable.NewLRU[replacementNonceKey, int](replacementNonceSize, nil, replacementNonceTTL),
 	}
 	maxRequestBodySizeBytes := DefaultMaxRequestBodySizeBytes
 	if config.MaxRequestBodySizeBytes != 0 {

proxy/proxy_test.go

@@ -6,13 +6,18 @@ import (
 	"fmt"
 	"io"
 	"log/slog"
+	"math/big"
 	"net"
 	"net/http"
 	"net/http/httptest"
 	"os"
 	"testing"
 	"time"
 
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/flashbots/go-utils/rpctypes"
 	"github.com/flashbots/go-utils/signature"
 	"github.com/stretchr/testify/require"
@@ -357,3 +362,113 @@ func TestProxySendToArchive(t *testing.T) {
 	expectedArchiveRequest := `{"method":"flashbots_newOrderEvents","params":[{"orderEvents":[{"eth_sendBundle":{"params":{"txs":null,"blockNumber":"0x7b","signingAddress":"0x9349365494be4f6205e5d44bdc7ec7dcd134becf"},"metadata":{"receivedAt":1730000000000}}},{"eth_sendBundle":{"params":{"txs":null,"blockNumber":"0x1c8","signingAddress":"0x9349365494be4f6205e5d44bdc7ec7dcd134becf"},"metadata":{"receivedAt":1730000000000}}}]}],"id":0,"jsonrpc":"2.0"}`
 	require.Equal(t, expectedArchiveRequest, archiveRequest.body)
 }
+
+func createTestTx(i int) *hexutil.Bytes {
+	privateKey, err := crypto.HexToECDSA("c7589782d55a642c8ced7794ddcb24b62d4ebefbb81001034cb46545ff80e39e")
+	if err != nil {
+		panic(err)
+	}
+
+	chainID := big.NewInt(1)
+	txData := &types.DynamicFeeTx{
+		ChainID:    chainID,
+		Nonce:      uint64(i),
+		GasTipCap:  big.NewInt(1),
+		GasFeeCap:  big.NewInt(1),
+		Gas:        21000,
+		To:         &common.Address{},
+		Value:      big.NewInt(0),
+		Data:       nil,
+		AccessList: nil,
+	}
+	tx, err := types.SignNewTx(privateKey, types.LatestSignerForChainID(big.NewInt(1)), txData)
+	if err != nil {
+		panic(err)
+	}
+	binary, err := tx.MarshalBinary()
+	if err != nil {
+		panic(err)
+	}
+	hexBytes := hexutil.Bytes(binary)
+	return &hexBytes
+}
+
+func TestProxyShareBundleReplacementUUIDAndCancellation(t *testing.T) {
+	defer func() {
+		proxiesFlushQueue()
+		for {
+			select {
+			case <-time.After(time.Millisecond * 100):
+				expectNoRequest(t, archiveServerRequests)
+				return
+			case <-archiveServerRequests:
+			}
+		}
+	}()
+
+	signer, err := signature.NewSignerFromHexPrivateKey("0xd63b3c447fdea415a05e4c0b859474d14105a88178efdf350bc9f7b05be3cc58")
+	require.NoError(t, err)
+	client, err := RPCClientWithCertAndSigner(proxies[0].localServerEndpoint, proxies[0].proxy.PublicCertPEM, signer)
+	require.NoError(t, err)
+
+	// we start with no peers
+	builderHubPeers = nil
+	err = proxies[0].proxy.RegisterSecrets(context.Background())
+	require.NoError(t, err)
+	proxiesUpdatePeers(t)
+
+	// first call
+	resp, err := client.Call(context.Background(), MevSendBundleMethod, &rpctypes.MevSendBundleArgs{
+		Version:         "v0.1",
+		ReplacementUUID: "550e8400-e29b-41d4-a716-446655440000",
+		Inclusion: rpctypes.MevBundleInclusion{
+			BlockNumber: 10,
+		},
+		Body: []rpctypes.MevBundleBody{
+			{
+				Tx: createTestTx(0),
+			},
+		},
+	})
+	require.NoError(t, err)
+	require.Nil(t, resp.Error)
+
+	expectedRequest := `{"method":"mev_sendBundle","params":[{"version":"v0.1","replacementUuid":"550e8400-e29b-41d4-a716-446655440000","inclusion":{"block":"0xa","maxBlock":"0x0"},"body":[{"tx":"0x02f862018001018252089400000000000000000000000000000000000000008080c001a05900a5ea3e4e07980b0d6276e2764b734be64d64c20f3eb87746c7ed1d72aa26a073f3a0877bd80098bd720afd1ba2c6d2d9c76d87cbc23f098d7be74902d9bfd4"}],"validity":{},"metadata":{"signer":"0x9349365494be4f6205e5d44bdc7ec7dcd134becf","replacementNonce":0}}],"id":0,"jsonrpc":"2.0"}`
+
+	builderRequest := expectRequest(t, proxies[0].localBuilderRequests)
+	require.Equal(t, expectedRequest, builderRequest.body)
+
+	// second call
+	resp, err = client.Call(context.Background(), MevSendBundleMethod, &rpctypes.MevSendBundleArgs{
+		Version:         "v0.1",
+		ReplacementUUID: "550e8400-e29b-41d4-a716-446655440000",
+		Inclusion: rpctypes.MevBundleInclusion{
+			BlockNumber: 10,
+		},
+		Body: []rpctypes.MevBundleBody{
+			{
+				Tx: createTestTx(1),
+			},
+		},
+	})
+	require.NoError(t, err)
+	require.Nil(t, resp.Error)
+
+	expectedRequest = `{"method":"mev_sendBundle","params":[{"version":"v0.1","replacementUuid":"550e8400-e29b-41d4-a716-446655440000","inclusion":{"block":"0xa","maxBlock":"0x0"},"body":[{"tx":"0x02f862010101018252089400000000000000000000000000000000000000008080c001a03b5edc6a7fe16f7c7bf25c56281b86107e742a922f900ac94293225b380fd5bea00f2ea6392842711064ca5c0fe12d812a60e8936ec8dc13ca95ecde8b262fd1fe"}],"validity":{},"metadata":{"signer":"0x9349365494be4f6205e5d44bdc7ec7dcd134becf","replacementNonce":1}}],"id":0,"jsonrpc":"2.0"}`
+
+	builderRequest = expectRequest(t, proxies[0].localBuilderRequests)
+	require.Equal(t, expectedRequest, builderRequest.body)
+
+	// cancell
+	resp, err = client.Call(context.Background(), MevSendBundleMethod, &rpctypes.MevSendBundleArgs{
+		Version:         "v0.1",
+		ReplacementUUID: "550e8400-e29b-41d4-a716-446655440000",
+	})
+	require.NoError(t, err)
+	require.Nil(t, resp.Error)
+
+	expectedRequest = `{"method":"mev_sendBundle","params":[{"version":"v0.1","replacementUuid":"550e8400-e29b-41d4-a716-446655440000","inclusion":{"block":"0x0","maxBlock":"0x0"},"body":null,"validity":{},"metadata":{"signer":"0x9349365494be4f6205e5d44bdc7ec7dcd134becf","replacementNonce":2,"cancelled":true}}],"id":0,"jsonrpc":"2.0"}`
+
+	builderRequest = expectRequest(t, proxies[0].localBuilderRequests)
+	require.Equal(t, expectedRequest, builderRequest.body)
+}