go-ethereum/tests/fuzzers/trie/trie-fuzzer.go

202 lines
4.7 KiB
Go

// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package trie
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/trie"
"github.com/ethereum/go-ethereum/trie/trienode"
)
// randTest performs random trie operations.
// Instances of this test are created by Generate.
type randTest []randTestStep
type randTestStep struct {
op int
key []byte // for opUpdate, opDelete, opGet
value []byte // for opUpdate
err error // for debugging
}
type proofDb struct{}
func (proofDb) Put(key []byte, value []byte) error {
return nil
}
func (proofDb) Delete(key []byte) error {
return nil
}
const (
opUpdate = iota
opDelete
opGet
opHash
opCommit
opItercheckhash
opProve
opMax // boundary value, not an actual op
)
type dataSource struct {
input []byte
reader *bytes.Reader
}
func newDataSource(input []byte) *dataSource {
return &dataSource{
input, bytes.NewReader(input),
}
}
func (ds *dataSource) readByte() byte {
if b, err := ds.reader.ReadByte(); err != nil {
return 0
} else {
return b
}
}
func (ds *dataSource) Read(buf []byte) (int, error) {
return ds.reader.Read(buf)
}
func (ds *dataSource) Ended() bool {
return ds.reader.Len() == 0
}
func Generate(input []byte) randTest {
var allKeys [][]byte
r := newDataSource(input)
genKey := func() []byte {
if len(allKeys) < 2 || r.readByte() < 0x0f {
// new key
key := make([]byte, r.readByte()%50)
r.Read(key)
allKeys = append(allKeys, key)
return key
}
// use existing key
return allKeys[int(r.readByte())%len(allKeys)]
}
var steps randTest
for i := 0; !r.Ended(); i++ {
step := randTestStep{op: int(r.readByte()) % opMax}
switch step.op {
case opUpdate:
step.key = genKey()
step.value = make([]byte, 8)
binary.BigEndian.PutUint64(step.value, uint64(i))
case opGet, opDelete, opProve:
step.key = genKey()
}
steps = append(steps, step)
if len(steps) > 500 {
break
}
}
return steps
}
// Fuzz is the fuzzing entry-point.
// The function must return
//
// - 1 if the fuzzer should increase priority of the
// given input during subsequent fuzzing (for example, the input is lexically
// correct and was parsed successfully);
// - -1 if the input must not be added to corpus even if gives new coverage; and
// - 0 otherwise
//
// other values are reserved for future use.
func Fuzz(input []byte) int {
program := Generate(input)
if len(program) == 0 {
return 0
}
if err := runRandTest(program); err != nil {
panic(err)
}
return 1
}
func runRandTest(rt randTest) error {
var (
triedb = trie.NewDatabase(rawdb.NewMemoryDatabase())
tr = trie.NewEmpty(triedb)
origin = types.EmptyRootHash
values = make(map[string]string) // tracks content of the trie
)
for i, step := range rt {
switch step.op {
case opUpdate:
tr.MustUpdate(step.key, step.value)
values[string(step.key)] = string(step.value)
case opDelete:
tr.MustDelete(step.key)
delete(values, string(step.key))
case opGet:
v := tr.MustGet(step.key)
want := values[string(step.key)]
if string(v) != want {
rt[i].err = fmt.Errorf("mismatch for key %#x, got %#x want %#x", step.key, v, want)
}
case opHash:
tr.Hash()
case opCommit:
hash, nodes, err := tr.Commit(false)
if err != nil {
return err
}
if nodes != nil {
if err := triedb.Update(hash, origin, trienode.NewWithNodeSet(nodes), nil); err != nil {
return err
}
}
newtr, err := trie.New(trie.TrieID(hash), triedb)
if err != nil {
return err
}
tr = newtr
origin = hash
case opItercheckhash:
checktr := trie.NewEmpty(triedb)
it := trie.NewIterator(tr.MustNodeIterator(nil))
for it.Next() {
checktr.MustUpdate(it.Key, it.Value)
}
if tr.Hash() != checktr.Hash() {
return errors.New("hash mismatch in opItercheckhash")
}
case opProve:
rt[i].err = tr.Prove(step.key, proofDb{})
}
// Abort the test on error.
if rt[i].err != nil {
return rt[i].err
}
}
return nil
}