Fixing problems in MPT found by light client

mpt-witness-generator/README.md

@@ -71,14 +71,12 @@ What is changed compared to geth:
 
 ## Generate witnesses
 
-To generate witnesses for MPT circuit, go into witness folder and execute
+To generate witnesses for MPT circuit, execute
 
 ```
-go test gen_witness_from_infura_blockchain_test.go prepare_witness.go leaf.go extension_node.go modified_extension_node.go nodes.go test_tools.go branch.go util.go
+go test -v ./...
 ```
 
-to generate the tests that use Infura blockchain.
-
 To generate the tests that use a local blockchain you need a local `geth`. You would
 need to run something like:
 ```
@@ -93,14 +91,16 @@ database if you already have some accounts:
 geth removedb
 ```
 
-And to generate the tests:
+The witness files will appear in generated_witnesses folder.
+
+## Format the code
+
+To format the code use:
 
 ```
-go test gen_witness_from_local_blockchain_test.go prepare_witness.go leaf.go extension_node.go modified_extension_node.go nodes.go test_tools.go branch.go util.go
+gofmt -w ./*
 ```
 
-The witness files will appear in generated_witnesses folder.
-
 ## Calling from Rust
 
 Build:

mpt-witness-generator/oracle/preimage.go

@@ -1,27 +1,26 @@
 package oracle
 
 import (
+	"errors"
 	"fmt"
-	"io/ioutil"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 )
 
 var preimages = make(map[common.Hash][]byte)
 
-func Preimage(hash common.Hash) []byte {
+func Preimage(hash common.Hash) ([]byte, error) {
 	val, ok := preimages[hash]
-	key := fmt.Sprintf("/tmp/eth/%s", hash)
-	ioutil.WriteFile(key, val, 0644)
 	if !ok {
-		fmt.Println("can't find preimage", hash)
+		return nil, errors.New("can't find preimage")
 	}
 	comphash := crypto.Keccak256Hash(val)
 	if hash != comphash {
-		panic("corruption in hash " + hash.String())
+		fmt.Println("corruption in hash " + hash.String())
+		return nil, errors.New("corruption in hash " + hash.String())
 	}
-	return val
+	return val, nil
 }
 
 // TODO: Maybe we will want to have a seperate preimages for next block's preimages?

mpt-witness-generator/state/database.go

@@ -30,15 +30,14 @@ func NewDatabase(header types.Header) Database {
 // ContractCode retrieves a particular contract's code.
 func (db *Database) ContractCode(addrHash common.Hash, codeHash common.Hash) ([]byte, error) {
 	oracle.PrefetchCode(db.BlockNumber, addrHash)
-	code := oracle.Preimage(codeHash)
-	return code, nil
+	return oracle.Preimage(codeHash)
 }
 
 // ContractCodeSize retrieves a particular contracts code's size.
 func (db *Database) ContractCodeSize(addrHash common.Hash, codeHash common.Hash) (int, error) {
 	oracle.PrefetchCode(db.BlockNumber, addrHash)
-	code := oracle.Preimage(codeHash)
-	return len(code), nil
+	code, err := oracle.Preimage(codeHash)
+	return len(code), err
 }
 
 func (db *Database) CopyTrie(t Trie) Trie {
@@ -96,7 +95,7 @@ type Trie interface {
 	// and external (for account tries) references.
 	Commit(onleaf trie.LeafCallback) (common.Hash, error)
 
-	Prove(key []byte, fromLevel uint, proofDb ethdb.KeyValueWriter) ([]byte, [][]byte, bool, error)
+	Prove(key []byte, fromLevel uint, proofDb ethdb.KeyValueWriter) ([]byte, [][]byte, bool, bool, error)
 
 	GetNodeByNibbles(key []byte) ([]byte, error)
 

mpt-witness-generator/state/journal.go

@@ -161,7 +161,7 @@ func (ch resetObjectChange) dirtied() *common.Address {
 }
 
 func (ch suicideChange) revert(s *StateDB) {
-	obj := s.getStateObject(*ch.account)
+	obj := s.GetStateObject(*ch.account)
 	if obj != nil {
 		obj.suicided = ch.prev
 		obj.setBalance(ch.prevbalance)
@@ -182,31 +182,31 @@ func (ch touchChange) dirtied() *common.Address {
 }
 
 func (ch balanceChange) revert(s *StateDB) {
-	s.getStateObject(*ch.account).setBalance(ch.prev)
+	s.GetStateObject(*ch.account).setBalance(ch.prev)
 }
 
 func (ch balanceChange) dirtied() *common.Address {
 	return ch.account
 }
 
 func (ch nonceChange) revert(s *StateDB) {
-	s.getStateObject(*ch.account).setNonce(ch.prev)
+	s.GetStateObject(*ch.account).setNonce(ch.prev)
 }
 
 func (ch nonceChange) dirtied() *common.Address {
 	return ch.account
 }
 
 func (ch codeChange) revert(s *StateDB) {
-	s.getStateObject(*ch.account).setCode(common.BytesToHash(ch.prevhash), ch.prevcode)
+	s.GetStateObject(*ch.account).setCode(common.BytesToHash(ch.prevhash), ch.prevcode)
 }
 
 func (ch codeChange) dirtied() *common.Address {
 	return ch.account
 }
 
 func (ch storageChange) revert(s *StateDB) {
-	s.getStateObject(*ch.account).setState(ch.key, ch.prevalue)
+	s.GetStateObject(*ch.account).setState(ch.key, ch.prevalue)
 }
 
 func (ch storageChange) dirtied() *common.Address {

mpt-witness-generator/state/state_object.go

@@ -28,6 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/metrics"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/privacy-scaling-explorations/mpt-witness-generator/oracle"
+	"github.com/privacy-scaling-explorations/mpt-witness-generator/trie"
 )
 
 var emptyCodeHash = crypto.Keccak256(nil)
@@ -359,7 +360,7 @@ func (s *stateObject) updateTrie(db Database) Trie {
 			// Get absense proof of key in case the deletion needs the sister node.
 
 			// Note: commented for now because of `ExtNodeDeleted`
-			// oracle.PrefetchStorage(big.NewInt(db.BlockNumber.Int64()+1), s.address, key, trie.GenPossibleShortNodePreimage)
+			oracle.PrefetchStorage(big.NewInt(db.BlockNumber.Int64()+1), s.address, key, trie.GenPossibleShortNodePreimage)
 			s.setError(tr.TryDelete(key[:]))
 		} else {
 			//fmt.Println("update", s.address, key, value)