mirror of
https://gitlab.com/pulsechaincom/erigon-pulse.git
synced 2024-12-23 04:03:49 +00:00
109 lines
3.4 KiB
Go
109 lines
3.4 KiB
Go
// Copyright 2015 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 (
|
|
"hash"
|
|
|
|
"github.com/ethereum/go-ethereum/common"
|
|
"github.com/ethereum/go-ethereum/crypto/sha3"
|
|
)
|
|
|
|
var secureKeyPrefix = []byte("secure-key-")
|
|
|
|
// SecureTrie wraps a trie with key hashing. In a secure trie, all
|
|
// access operations hash the key using keccak256. This prevents
|
|
// calling code from creating long chains of nodes that
|
|
// increase the access time.
|
|
//
|
|
// Contrary to a regular trie, a SecureTrie can only be created with
|
|
// New and must have an attached database. The database also stores
|
|
// the preimage of each key.
|
|
//
|
|
// SecureTrie is not safe for concurrent use.
|
|
type SecureTrie struct {
|
|
*Trie
|
|
|
|
hash hash.Hash
|
|
secKeyBuf []byte
|
|
hashKeyBuf []byte
|
|
}
|
|
|
|
// NewSecure creates a trie with an existing root node from db.
|
|
//
|
|
// If root is the zero hash or the sha3 hash of an empty string, the
|
|
// trie is initially empty. Otherwise, New will panics if db is nil
|
|
// and returns ErrMissingRoot if the root node cannpt be found.
|
|
// Accessing the trie loads nodes from db on demand.
|
|
func NewSecure(root common.Hash, db Database) (*SecureTrie, error) {
|
|
if db == nil {
|
|
panic("NewSecure called with nil database")
|
|
}
|
|
trie, err := New(root, db)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &SecureTrie{Trie: trie}, nil
|
|
}
|
|
|
|
// Get returns the value for key stored in the trie.
|
|
// The value bytes must not be modified by the caller.
|
|
func (t *SecureTrie) Get(key []byte) []byte {
|
|
return t.Trie.Get(t.hashKey(key))
|
|
}
|
|
|
|
// Update associates key with value in the trie. Subsequent calls to
|
|
// Get will return value. If value has length zero, any existing value
|
|
// is deleted from the trie and calls to Get will return nil.
|
|
//
|
|
// The value bytes must not be modified by the caller while they are
|
|
// stored in the trie.
|
|
func (t *SecureTrie) Update(key, value []byte) {
|
|
hk := t.hashKey(key)
|
|
t.Trie.Update(hk, value)
|
|
t.Trie.db.Put(t.secKey(hk), key)
|
|
}
|
|
|
|
// Delete removes any existing value for key from the trie.
|
|
func (t *SecureTrie) Delete(key []byte) {
|
|
t.Trie.Delete(t.hashKey(key))
|
|
}
|
|
|
|
// GetKey returns the sha3 preimage of a hashed key that was
|
|
// previously used to store a value.
|
|
func (t *SecureTrie) GetKey(shaKey []byte) []byte {
|
|
key, _ := t.Trie.db.Get(t.secKey(shaKey))
|
|
return key
|
|
}
|
|
|
|
func (t *SecureTrie) secKey(key []byte) []byte {
|
|
t.secKeyBuf = append(t.secKeyBuf[:0], secureKeyPrefix...)
|
|
t.secKeyBuf = append(t.secKeyBuf, key...)
|
|
return t.secKeyBuf
|
|
}
|
|
|
|
func (t *SecureTrie) hashKey(key []byte) []byte {
|
|
if t.hash == nil {
|
|
t.hash = sha3.NewKeccak256()
|
|
t.hashKeyBuf = make([]byte, 32)
|
|
}
|
|
t.hash.Reset()
|
|
t.hash.Write(key)
|
|
t.hashKeyBuf = t.hash.Sum(t.hashKeyBuf[:0])
|
|
return t.hashKeyBuf
|
|
}
|