core/txpool/blobpool: remove conversion in GetBlobs (#32578)

This disables blob proof conversion in `GetBlobs` by default, making it
conditional.

---------

Co-authored-by: Felix Lange <fjl@twurst.com>

core/txpool/blobpool/blobpool.go

@@ -1331,7 +1331,11 @@ func (p *BlobPool) GetMetadata(hash common.Hash) *txpool.TxMetadata {
 //
 // This is a utility method for the engine API, enabling consensus clients to
 // retrieve blobs from the pools directly instead of the network.
-func (p *BlobPool) GetBlobs(vhashes []common.Hash, version byte) ([]*kzg4844.Blob, []kzg4844.Commitment, [][]kzg4844.Proof, error) {
+//
+// The version argument specifies the type of proofs to return, either the
+// blob proofs (version 0) or the cell proofs (version 1). Proofs conversion is
+// CPU intensive, so only done if explicitly requested with the convert flag.
+func (p *BlobPool) GetBlobs(vhashes []common.Hash, version byte, convert bool) ([]*kzg4844.Blob, []kzg4844.Commitment, [][]kzg4844.Proof, error) {
 	var (
 		blobs       = make([]*kzg4844.Blob, len(vhashes))
 		commitments = make([]kzg4844.Commitment, len(vhashes))
@@ -1343,13 +1347,14 @@ func (p *BlobPool) GetBlobs(vhashes []common.Hash, version byte) ([]*kzg4844.Blo
 	for i, h := range vhashes {
 		indices[h] = append(indices[h], i)
 	}
+
 	for _, vhash := range vhashes {
-		// Skip duplicate vhash that was already resolved in a previous iteration
 		if _, ok := filled[vhash]; ok {
+			// Skip vhash that was already resolved in a previous iteration
 			continue
 		}
-		// Retrieve the corresponding blob tx with the vhash, skip blob resolution
-		// if it's not found locally and place the null instead.
+
+		// Retrieve the corresponding blob tx with the vhash.
 		p.lock.RLock()
 		txID, exists := p.lookup.storeidOfBlob(vhash)
 		p.lock.RUnlock()
@@ -1379,6 +1384,14 @@ func (p *BlobPool) GetBlobs(vhashes []common.Hash, version byte) ([]*kzg4844.Blo
 			if !ok {
 				continue // non-interesting blob
 			}
+			// Mark hash as seen.
+			filled[hash] = struct{}{}
+			if sidecar.Version != version && !convert {
+				// Skip blobs with incompatible version. Note we still track the blob hash
+				// in `filled` here, ensuring that we do not resolve this tx another time.
+				continue
+			}
+			// Get or convert the proof.
 			var pf []kzg4844.Proof
 			switch version {
 			case types.BlobSidecarVersion0:
@@ -1411,7 +1424,6 @@ func (p *BlobPool) GetBlobs(vhashes []common.Hash, version byte) ([]*kzg4844.Blo
 				commitments[index] = sidecar.Commitments[i]
 				proofs[index] = pf
 			}
-			filled[hash] = struct{}{}
 		}
 	}
 	return blobs, commitments, proofs, nil

core/txpool/blobpool/blobpool_test.go

@@ -423,11 +423,11 @@ func verifyBlobRetrievals(t *testing.T, pool *BlobPool) {
 			hashes = append(hashes, tx.vhashes...)
 		}
 	}
-	blobs1, _, proofs1, err := pool.GetBlobs(hashes, types.BlobSidecarVersion0)
+	blobs1, _, proofs1, err := pool.GetBlobs(hashes, types.BlobSidecarVersion0, false)
 	if err != nil {
 		t.Fatal(err)
 	}
-	blobs2, _, proofs2, err := pool.GetBlobs(hashes, types.BlobSidecarVersion1)
+	blobs2, _, proofs2, err := pool.GetBlobs(hashes, types.BlobSidecarVersion1, false)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -441,22 +441,18 @@ func verifyBlobRetrievals(t *testing.T, pool *BlobPool) {
 		return
 	}
 	for i, hash := range hashes {
-		// If an item is missing, but shouldn't, error
-		if blobs1[i] == nil || proofs1[i] == nil {
-			t.Errorf("tracked blob retrieval failed: item %d, hash %x", i, hash)
-			continue
-		}
-		if blobs2[i] == nil || proofs2[i] == nil {
+		// If an item is missing from both, but shouldn't, error
+		if (blobs1[i] == nil || proofs1[i] == nil) && (blobs2[i] == nil || proofs2[i] == nil) {
 			t.Errorf("tracked blob retrieval failed: item %d, hash %x", i, hash)
 			continue
 		}
 		// Item retrieved, make sure it matches the expectation
 		index := testBlobIndices[hash]
-		if *blobs1[i] != *testBlobs[index] || proofs1[i][0] != testBlobProofs[index] {
+		if blobs1[i] != nil && (*blobs1[i] != *testBlobs[index] || proofs1[i][0] != testBlobProofs[index]) {
 			t.Errorf("retrieved blob or proof mismatch: item %d, hash %x", i, hash)
 			continue
 		}
-		if *blobs2[i] != *testBlobs[index] || !slices.Equal(proofs2[i], testBlobCellProofs[index]) {
+		if blobs2[i] != nil && (*blobs2[i] != *testBlobs[index] || !slices.Equal(proofs2[i], testBlobCellProofs[index])) {
 			t.Errorf("retrieved blob or proof mismatch: item %d, hash %x", i, hash)
 			continue
 		}
@@ -1926,8 +1922,9 @@ func TestGetBlobs(t *testing.T) {
 	cases := []struct {
 		start      int
 		limit      int
-		fillRandom bool
-		version    byte
+		fillRandom bool // Whether to randomly fill some of the requested blobs with unknowns
+		version    byte // Blob sidecar version to request
+		convert    bool // Whether to convert version on retrieval
 	}{
 		{
 			start: 0, limit: 6,
@@ -1993,6 +1990,11 @@ func TestGetBlobs(t *testing.T) {
 			start: 0, limit: 18, fillRandom: true,
 			version: types.BlobSidecarVersion1,
 		},
+		{
+			start: 0, limit: 18, fillRandom: true,
+			version: types.BlobSidecarVersion1,
+			convert: true, // Convert some version 0 blobs to version 1 while retrieving
+		},
 	}
 	for i, c := range cases {
 		var (
@@ -2014,7 +2016,7 @@ func TestGetBlobs(t *testing.T) {
 			filled[len(vhashes)] = struct{}{}
 			vhashes = append(vhashes, testrand.Hash())
 		}
-		blobs, _, proofs, err := pool.GetBlobs(vhashes, c.version)
+		blobs, _, proofs, err := pool.GetBlobs(vhashes, c.version, c.convert)
 		if err != nil {
 			t.Errorf("Unexpected error for case %d, %v", i, err)
 		}
@@ -2029,6 +2031,7 @@ func TestGetBlobs(t *testing.T) {
 
 		var unknown int
 		for j := 0; j < len(blobs); j++ {
+			testBlobIndex := c.start + j - unknown
 			if _, exist := filled[j]; exist {
 				if blobs[j] != nil || proofs[j] != nil {
 					t.Errorf("Unexpected blob and proof, item %d", j)
@@ -2038,17 +2041,22 @@ func TestGetBlobs(t *testing.T) {
 			}
 			// If an item is missing, but shouldn't, error
 			if blobs[j] == nil || proofs[j] == nil {
-				t.Errorf("tracked blob retrieval failed: item %d, hash %x", j, vhashes[j])
+				// This is only an error if there was no version mismatch
+				if c.convert ||
+					(c.version == types.BlobSidecarVersion1 && 6 <= testBlobIndex && testBlobIndex < 12) ||
+					(c.version == types.BlobSidecarVersion0 && (testBlobIndex < 6 || 12 <= testBlobIndex)) {
+					t.Errorf("tracked blob retrieval failed: item %d, hash %x", j, vhashes[j])
+				}
 				continue
 			}
 			// Item retrieved, make sure the blob matches the expectation
-			if *blobs[j] != *testBlobs[c.start+j-unknown] {
+			if *blobs[j] != *testBlobs[testBlobIndex] {
 				t.Errorf("retrieved blob mismatch: item %d, hash %x", j, vhashes[j])
 				continue
 			}
 			// Item retrieved, make sure the proof matches the expectation
 			if c.version == types.BlobSidecarVersion0 {
-				if proofs[j][0] != testBlobProofs[c.start+j-unknown] {
+				if proofs[j][0] != testBlobProofs[testBlobIndex] {
 					t.Errorf("retrieved proof mismatch: item %d, hash %x", j, vhashes[j])
 				}
 			} else {

eth/catalyst/api.go

@@ -495,7 +495,7 @@ func (api *ConsensusAPI) GetBlobsV1(hashes []common.Hash) ([]*engine.BlobAndProo
 	if len(hashes) > 128 {
 		return nil, engine.TooLargeRequest.With(fmt.Errorf("requested blob count too large: %v", len(hashes)))
 	}
-	blobs, _, proofs, err := api.eth.BlobTxPool().GetBlobs(hashes, types.BlobSidecarVersion0)
+	blobs, _, proofs, err := api.eth.BlobTxPool().GetBlobs(hashes, types.BlobSidecarVersion0, false)
 	if err != nil {
 		return nil, engine.InvalidParams.With(err)
 	}
@@ -555,7 +555,7 @@ func (api *ConsensusAPI) GetBlobsV2(hashes []common.Hash) ([]*engine.BlobAndProo
 		return nil, nil
 	}
 
-	blobs, _, proofs, err := api.eth.BlobTxPool().GetBlobs(hashes, types.BlobSidecarVersion1)
+	blobs, _, proofs, err := api.eth.BlobTxPool().GetBlobs(hashes, types.BlobSidecarVersion1, false)
 	if err != nil {
 		return nil, engine.InvalidParams.With(err)
 	}