EIP-1186 eth_getProof (#17737)

* first impl of eth_getProof

* fixed docu

* added comments and refactored based on comments from holiman

* created structs

* handle errors correctly

* change Value to *hexutil.Big in order to have the same output as parity

* use ProofList as return type

2 files changed, 30 insertions, 0 deletions

diff --git a/core/state/statedb.go b/core/state/statedb.go
index 216667ce9..b1bb53ed0 100644
--- a/core/state/statedb.go
+++ b/core/state/statedb.go
@@ -18,6 +18,7 @@
 package state
 
 import (
+	"errors"
 	"fmt"
 	"math/big"
 	"sort"
@@ -25,6 +26,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/rlp"
@@ -256,6 +258,24 @@ func (self *StateDB) GetState(addr common.Address, hash common.Hash) common.Hash
 	return common.Hash{}
 }
 
+// GetProof returns the MerkleProof for a given Account
+func (self *StateDB) GetProof(a common.Address) (vm.ProofList, error) {
+	var proof vm.ProofList
+	err := self.trie.Prove(crypto.Keccak256(a.Bytes()), 0, &proof)
+	return proof, err
+}
+
+// GetProof returns the StorageProof for given key
+func (self *StateDB) GetStorageProof(a common.Address, key common.Hash) (vm.ProofList, error) {
+	var proof vm.ProofList
+	trie := self.StorageTrie(a)
+	if trie == nil {
+		return proof, errors.New("storage trie for requested address does not exist")
+	}
+	err := trie.Prove(crypto.Keccak256(key.Bytes()), 0, &proof)
+	return proof, err
+}
+
 // GetCommittedState retrieves a value from the given account's committed storage trie.
 func (self *StateDB) GetCommittedState(addr common.Address, hash common.Hash) common.Hash {
 	stateObject := self.getStateObject(addr)
diff --git a/core/vm/interface.go b/core/vm/interface.go
index fc15082f1..1ae98cf7a 100644
--- a/core/vm/interface.go
+++ b/core/vm/interface.go
@@ -35,6 +35,8 @@ type StateDB interface {
 	SetNonce(common.Address, uint64)
 
 	GetCodeHash(common.Address) common.Hash
+	GetProof(common.Address) (ProofList, error)
+	GetStorageProof(common.Address, common.Hash) (ProofList, error)
 	GetCode(common.Address) []byte
 	SetCode(common.Address, []byte)
 	GetCodeSize(common.Address) int
@@ -78,3 +80,11 @@ type CallContext interface {
 	// Create a new contract
 	Create(env *EVM, me ContractRef, data []byte, gas, value *big.Int) ([]byte, common.Address, error)
 }
+
+// MerkleProof
+type ProofList [][]byte
+
+func (n *ProofList) Put(key []byte, value []byte) error {
+	*n = append(*n, value)
+	return nil
+}