fix(zktrie): fix deletion proofs and collect them in commiting phase (#263)

* new deletion proof

* complete tracer and test

* extend proof for parallel tracing

* integrating into blocktrace

* lint

* deduplication of deletion proofs

* fix an issue on marking deletion

* fixs since last review

* Update version.go

---------

Co-authored-by: HAOYUatHZ <[email protected]>
Co-authored-by: Ubuntu <[email protected]>

Author: 3 people

core/state/state_prove.go

@@ -0,0 +1,88 @@
+package state
+
+import (
+	"fmt"
+
+	zkt "github.com/scroll-tech/zktrie/types"
+
+	zktrie "github.com/scroll-tech/go-ethereum/trie"
+
+	"github.com/scroll-tech/go-ethereum/common"
+	"github.com/scroll-tech/go-ethereum/crypto"
+	"github.com/scroll-tech/go-ethereum/ethdb"
+)
+
+type TrieProve interface {
+	Prove(key []byte, fromLevel uint, proofDb ethdb.KeyValueWriter) error
+}
+
+type ZktrieProofTracer struct {
+	*zktrie.ProofTracer
+}
+
+// MarkDeletion overwrite the underlayer method with secure key
+func (t ZktrieProofTracer) MarkDeletion(key common.Hash) {
+	key_s, _ := zkt.ToSecureKeyBytes(key.Bytes())
+	t.ProofTracer.MarkDeletion(key_s.Bytes())
+}
+
+// Merge overwrite underlayer method with proper argument
+func (t ZktrieProofTracer) Merge(another ZktrieProofTracer) {
+	t.ProofTracer.Merge(another.ProofTracer)
+}
+
+func (t ZktrieProofTracer) Available() bool {
+	return t.ProofTracer != nil
+}
+
+// NewProofTracer is not in Db interface and used explictily for reading proof in storage trie (not updated by the dirty value)
+func (s *StateDB) NewProofTracer(trieS Trie) ZktrieProofTracer {
+	if s.IsZktrie() {
+		zkTrie := trieS.(*zktrie.ZkTrie)
+		if zkTrie == nil {
+			panic("unexpected trie type for zktrie")
+		}
+		return ZktrieProofTracer{zkTrie.NewProofTracer()}
+	}
+	return ZktrieProofTracer{}
+}
+
+// GetStorageTrieForProof is not in Db interface and used explictily for reading proof in storage trie (not updated by the dirty value)
+func (s *StateDB) GetStorageTrieForProof(addr common.Address) (Trie, error) {
+
+	// try the trie in stateObject first, else we would create one
+	stateObject := s.getStateObject(addr)
+	if stateObject == nil {
+		// still return a empty trie
+		addrHash := crypto.Keccak256Hash(addr[:])
+		dummy_trie, _ := s.db.OpenStorageTrie(addrHash, common.Hash{})
+		return dummy_trie, nil
+	}
+
+	trie := stateObject.trie
+	var err error
+	if trie == nil {
+		// use a new, temporary trie
+		trie, err = s.db.OpenStorageTrie(stateObject.addrHash, stateObject.data.Root)
+		if err != nil {
+			return nil, fmt.Errorf("can't create storage trie on root %s: %v ", stateObject.data.Root, err)
+		}
+	}
+
+	return trie, nil
+}
+
+// GetSecureTrieProof handle any interface with Prove (should be a Trie in most case) and
+// deliver the proof in bytes
+func (s *StateDB) GetSecureTrieProof(trieProve TrieProve, key common.Hash) ([][]byte, error) {
+
+	var proof proofList
+	var err error
+	if s.IsZktrie() {
+		key_s, _ := zkt.ToSecureKeyBytes(key.Bytes())
+		err = trieProve.Prove(key_s.Bytes(), 0, &proof)
+	} else {
+		err = trieProve.Prove(crypto.Keccak256(key.Bytes()), 0, &proof)
+	}
+	return proof, err
+}

core/state/statedb.go

@@ -350,56 +350,13 @@ func (s *StateDB) GetRootHash() common.Hash {
 	return s.trie.Hash()
 }
 
-// StorageTrieProof is not in Db interface and used explictily for reading proof in storage trie (not the dirty value)
-// For zktrie it also provide required data for predict the deletion, else it just fallback to GetStorageProof
-func (s *StateDB) GetStorageTrieProof(a common.Address, key common.Hash) ([][]byte, []byte, error) {
-
-	// try the trie in stateObject first, else we would create one
-	stateObject := s.getStateObject(a)
-	if stateObject == nil {
-		return nil, nil, errors.New("storage trie for requested address does not exist")
-	}
-
-	trieS := stateObject.trie
-	var err error
-	if trieS == nil {
-		// use a new, temporary trie
-		trieS, err = s.db.OpenStorageTrie(stateObject.addrHash, stateObject.data.Root)
-		if err != nil {
-			return nil, nil, fmt.Errorf("can't create storage trie on root %s: %v ", stateObject.data.Root, err)
-		}
-	}
-
-	var proof proofList
-	var sibling []byte
-	if s.IsZktrie() {
-		zkTrie := trieS.(*trie.ZkTrie)
-		if zkTrie == nil {
-			panic("unexpected trie type for zktrie")
-		}
-		key_s, _ := zkt.ToSecureKeyBytes(key.Bytes())
-		sibling, err = zkTrie.ProveWithDeletion(key_s.Bytes(), 0, &proof)
-	} else {
-		err = trieS.Prove(crypto.Keccak256(key.Bytes()), 0, &proof)
-	}
-	return proof, sibling, err
-}
-
 // GetStorageProof returns the Merkle proof for given storage slot.
 func (s *StateDB) GetStorageProof(a common.Address, key common.Hash) ([][]byte, error) {
-	var proof proofList
 	trie := s.StorageTrie(a)
 	if trie == nil {
-		return proof, errors.New("storage trie for requested address does not exist")
+		return nil, errors.New("storage trie for requested address does not exist")
 	}
-	var err error
-	if s.IsZktrie() {
-		key_s, _ := zkt.ToSecureKeyBytes(key.Bytes())
-		err = trie.Prove(key_s.Bytes(), 0, &proof)
-	} else {
-		err = trie.Prove(crypto.Keccak256(key.Bytes()), 0, &proof)
-	}
-	return proof, err
+	return s.GetSecureTrieProof(trie, key)
 }
 
 // GetCommittedState retrieves a value from the given account's committed storage trie.

eth/tracers/api_blocktrace.go

@@ -1,6 +1,7 @@
 package tracers
 
 import (
+	"bytes"
 	"context"
 	"errors"
 	"fmt"
@@ -42,6 +43,8 @@ type traceEnv struct {
 	// this lock is used to protect StorageTrace's read and write mutual exclusion.
 	sMu sync.Mutex
 	*types.StorageTrace
+	// zktrie tracer is used for zktrie storage to build additional deletion proof
+	zkTrieTracer     map[string]state.ZktrieProofTracer
 	executionResults []*types.ExecutionResult
 }
 
@@ -119,6 +122,7 @@ func (api *API) createTraceEnv(ctx context.Context, config *TraceConfig, block *
 			Proofs:        make(map[string][]hexutil.Bytes),
 			StorageProofs: make(map[string]map[string][]hexutil.Bytes),
 		},
+		zkTrieTracer:     make(map[string]state.ZktrieProofTracer),
 		executionResults: make([]*types.ExecutionResult, block.Transactions().Len()),
 	}
 
@@ -189,6 +193,18 @@ func (api *API) getBlockTrace(block *types.Block, env *traceEnv) (*types.BlockTr
 	close(jobs)
 	pend.Wait()
 
+	// after all tx has been traced, collect "deletion proof" for zktrie
+	for _, tracer := range env.zkTrieTracer {
+		delProofs, err := tracer.GetDeletionProofs()
+		if err != nil {
+			log.Error("deletion proof failure", "error", err)
+		} else {
+			for _, proof := range delProofs {
+				env.DeletionProofs = append(env.DeletionProofs, proof)
+			}
+		}
+	}
+
 	// If execution failed in between, abort
 	select {
 	case err := <-errCh:
@@ -299,22 +315,47 @@ func (api *API) getTxResult(env *traceEnv, state *state.StateDB, index int, bloc
 
 	proofStorages := tracer.UpdatedStorages()
 	for addr, keys := range proofStorages {
-		for key := range keys {
+		env.sMu.Lock()
+		trie, err := state.GetStorageTrieForProof(addr)
+		if err != nil {
+			// but we still continue to next address
+			log.Error("Storage trie not available", "error", err, "address", addr)
+			env.sMu.Unlock()
+			continue
+		}
+		zktrieTracer := state.NewProofTracer(trie)
+		env.sMu.Unlock()
+
+		for key, values := range keys {
 			addrStr := addr.String()
 			keyStr := key.String()
+			isDelete := bytes.Equal(values.Bytes(), common.Hash{}.Bytes())
 
 			env.sMu.Lock()
 			m, existed := env.StorageProofs[addrStr]
 			if !existed {
 				m = make(map[string][]hexutil.Bytes)
 				env.StorageProofs[addrStr] = m
+				if zktrieTracer.Available() {
+					env.zkTrieTracer[addrStr] = zktrieTracer
+				}
 			} else if _, existed := m[keyStr]; existed {
+				// still need to touch tracer for deletion
+				if isDelete && zktrieTracer.Available() {
+					env.zkTrieTracer[addrStr].MarkDeletion(key)
+				}
 				env.sMu.Unlock()
 				continue
 			}
 			env.sMu.Unlock()
 
-			proof, sibling, err := state.GetStorageTrieProof(addr, key)
+			var proof [][]byte
+			var err error
+			if zktrieTracer.Available() {
+				proof, err = state.GetSecureTrieProof(zktrieTracer, key)
+			} else {
+				proof, err = state.GetSecureTrieProof(trie, key)
+			}
 			if err != nil {
 				log.Error("Storage proof not available", "error", err, "address", addrStr, "key", keyStr)
 				// but we still mark the proofs map with nil array
@@ -325,8 +366,11 @@ func (api *API) getTxResult(env *traceEnv, state *state.StateDB, index int, bloc
 			}
 			env.sMu.Lock()
 			m[keyStr] = wrappedProof
-			if sibling != nil {
-				env.DeletionProofs = append(env.DeletionProofs, sibling)
+			if zktrieTracer.Available() {
+				if isDelete {
+					zktrieTracer.MarkDeletion(key)
+				}
+				env.zkTrieTracer[addrStr].Merge(zktrieTracer)
 			}
 			env.sMu.Unlock()
 		}

params/version.go

@@ -24,7 +24,7 @@ import (
 const (
 	VersionMajor = 3       // Major version component of the current release
 	VersionMinor = 1       // Minor version component of the current release
-	VersionPatch = 10      // Patch version component of the current release
+	VersionPatch = 11      // Patch version component of the current release
 	VersionMeta  = "alpha" // Version metadata to append to the version string
 )
 

trie/zk_trie.go

@@ -174,49 +174,29 @@ func (t *ZkTrie) NodeIterator(start []byte) NodeIterator {
 // nodes of the longest existing prefix of the key (at least the root node), ending
 // with the node that proves the absence of the key.
 func (t *ZkTrie) Prove(key []byte, fromLevel uint, proofDb ethdb.KeyValueWriter) error {
-	// omit sibling, which is not required for proving only
-	_, err := t.ProveWithDeletion(key, fromLevel, proofDb)
-	return err
-}
-
-// ProveWithDeletion is the implement of Prove, it also return possible sibling node
-// (if there is, i.e. the node of key exist and is not the only node in trie)
-// so witness generator can predict the final state root after deletion of this key
-// the returned sibling node has no key along with it for witness generator must decode
-// the node for its purpose
-func (t *ZkTrie) ProveWithDeletion(key []byte, fromLevel uint, proofDb ethdb.KeyValueWriter) (sibling []byte, err error) {
-	err = t.ZkTrie.ProveWithDeletion(key, fromLevel,
-		func(n *zktrie.Node) error {
-			nodeHash, err := n.NodeHash()
-			if err != nil {
-				return err
-			}
+	err := t.ZkTrie.Prove(key, fromLevel, func(n *zktrie.Node) error {
+		nodeHash, err := n.NodeHash()
+		if err != nil {
+			return err
+		}
 
-			if n.Type == zktrie.NodeTypeLeaf {
-				preImage := t.GetKey(n.NodeKey.Bytes())
-				if len(preImage) > 0 {
-					n.KeyPreimage = &zkt.Byte32{}
-					copy(n.KeyPreimage[:], preImage)
-					//return fmt.Errorf("key preimage not found for [%x] ref %x", n.NodeKey.Bytes(), k.Bytes())
-				}
-			}
-			return proofDb.Put(nodeHash[:], n.Value())
-		},
-		func(_ *zktrie.Node, n *zktrie.Node) {
-			// the sibling for each leaf should be unique except for EmptyNode
-			if n != nil && n.Type != zktrie.NodeTypeEmpty {
-				sibling = n.Value()
+		if n.Type == zktrie.NodeTypeLeaf {
+			preImage := t.GetKey(n.NodeKey.Bytes())
+			if len(preImage) > 0 {
+				n.KeyPreimage = &zkt.Byte32{}
+				copy(n.KeyPreimage[:], preImage)
+				//return fmt.Errorf("key preimage not found for [%x] ref %x", n.NodeKey.Bytes(), k.Bytes())
 			}
-		},
-	)
+		}
+		return proofDb.Put(nodeHash[:], n.Value())
+	})
 	if err != nil {
-		return
+		return err
 	}
 
 	// we put this special kv pair in db so we can distinguish the type and
 	// make suitable Proof
-	err = proofDb.Put(magicHash, zktrie.ProofMagicBytes())
-	return
+	return proofDb.Put(magicHash, zktrie.ProofMagicBytes())
 }
 
 // VerifyProof checks merkle proofs. The given proof must contain the value for