// 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 implements a private key management facility.
//
// This abstracts part of a user's interaction with an account she controls.
package accounts
import (
"crypto/ecdsa"
crand "crypto/rand"
"errors"
"fmt"
"sync"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
)
var (
ErrLocked = errors.New("account is locked")
ErrNoKeys = errors.New("no keys in store")
)
type Account struct {
Address common.Address
}
func (acc *Account) MarshalJSON() ([]byte, error) {
return []byte(`"` + acc.Address.Hex() + `"`), nil
}
type Manager struct {
keyStore keyStore
unlocked map[common.Address]*unlocked
mutex sync.RWMutex
}
type unlocked struct {
*Key
abort chan struct{}
}
func NewManager(keydir string, scryptN, scryptP int) *Manager {
return &Manager{
keyStore: newKeyStorePassphrase(keydir, scryptN, scryptP),
unlocked: make(map[common.Address]*unlocked),
}
}
func NewPlaintextManager(keydir string) *Manager {
return &Manager{
keyStore: newKeyStorePlain(keydir),
unlocked: make(map[common.Address]*unlocked),
}
}
func (am *Manager) HasAddress(addr common.Address) bool {
accounts := am.Accounts()
for _, acct := range accounts {
if acct.Address == addr {
return true
}
}
return false
}
func (am *Manager) DeleteAccount(a Account, auth string) error {
return am.keyStore.DeleteKey(a.Address, auth)
}
func (am *Manager) Sign(a Account, toSign []byte) (signature []byte, err error) {
am.mutex.RLock()
defer am.mutex.RUnlock()
unlockedKey, found := am.unlocked[a.Address]
if !found {
return nil, ErrLocked
}
signature, err = crypto.Sign(toSign, unlockedKey.PrivateKey)
return signature, err
}
// Unlock unlocks the given account indefinitely.
func (am *Manager) Unlock(a Account, keyAuth string) error {
return am.TimedUnlock(a, keyAuth, 0)
}
func (am *Manager) Lock(addr common.Address) error {
am.mutex.Lock()
if unl, found := am.unlocked[addr]; found {
am.mutex.Unlock()
am.expire(addr, unl, time.Duration(0)*time.Nanosecond)
} else {
am.mutex.Unlock()
}
return nil
}
// TimedUnlock unlocks the account with the given address. The account
// stays unlocked for the duration of timeout. A timeout of 0 unlocks the account
// until the program exits.
//
// If the accout is already unlocked, TimedUnlock extends or shortens
// the active unlock timeout.
func (am *Manager) TimedUnlock(a Account, keyAuth string, timeout time.Duration) error {
key, err := am.keyStore.GetKey(a.Address, keyAuth)
if err != nil {
return err
}
var u *unlocked
am.mutex.Lock()
defer am.mutex.Unlock()
var found bool
u, found = am.unlocked[a.Address]
if found {
// terminate dropLater for this key to avoid unexpected drops.
if u.abort != nil {
close(u.abort)
}
}
if timeout > 0 {
u = &unlocked{Key: key, abort: make(chan struct{})}
go am.expire(a.Address, u, timeout)
} else {
u = &unlocked{Key: key}
}
am.unlocked[a.Address] = u
return nil
}
func (am *Manager) expire(addr common.Address, u *unlocked, timeout time.Duration) {
t := time.NewTimer(timeout)
defer t.Stop()
select {
case <-u.abort:
// just quit
case <-t.C:
am.mutex.Lock()
// only drop if it's still the same key instance that dropLater
// was launched with. we can check that using pointer equality
// because the map stores a new pointer every time the key is
// unlocked.
if am.unlocked[addr] == u {
zeroKey(u.PrivateKey)
delete(am.unlocked, addr)
}
am.mutex.Unlock()
}
}
func (am *Manager) NewAccount(auth string) (Account, error) {
key, err := am.keyStore.GenerateNewKey(crand.Reader, auth)
if err != nil {
return Account{}, err
}
return Account{Address: key.Address}, nil
}
func (am *Manager) AccountByIndex(index int) (Account, error) {
addrs, err := am.keyStore.GetKeyAddresses()
if err != nil {
return Account{}, err
}
if index < 0 || index >= len(addrs) {
return Account{}, fmt.Errorf("account index %d not in range [0, %d]", index, len(addrs)-1)
}
return Account{Address: addrs[index]}, nil
}
func (am *Manager) Accounts() []Account {
addresses, _ := am.keyStore.GetKeyAddresses()
accounts := make([]Account, len(addresses))
for i, addr := range addresses {
accounts[i] = Account{
Address: addr,
}
}
return accounts
}
// zeroKey zeroes a private key in memory.
func zeroKey(k *ecdsa.PrivateKey) {
b := k.D.Bits()
for i := range b {
b[i] = 0
}
}
// USE WITH CAUTION = this will save an unencrypted private key on disk
// no cli or js interface
func (am *Manager) Export(path string, a Account, keyAuth string) error {
key, err := am.keyStore.GetKey(a.Address, keyAuth)
if err != nil {
return err
}
return crypto.SaveECDSA(path, key.PrivateKey)
}
func (am *Manager) Import(path string, keyAuth string) (Account, error) {
priv, err := crypto.LoadECDSA(path)
if err != nil {
return Account{}, err
}
return am.ImportECDSA(priv, keyAuth)
}
func (am *Manager) ImportECDSA(priv *ecdsa.PrivateKey, keyAuth string) (Account, error) {
key := newKeyFromECDSA(priv)
if err := am.keyStore.StoreKey(key, keyAuth); err != nil {
return Account{}, err
}
return Account{Address: key.Address}, nil
}
func (am *Manager) Update(a Account, authFrom, authTo string) (err error) {
var key *Key
key, err = am.keyStore.GetKey(a.Address, authFrom)
if err == nil {
err = am.keyStore.StoreKey(key, authTo)
if err == nil {
am.keyStore.Cleanup(a.Address)
}
}
return
}
func (am *Manager) ImportPreSaleKey(keyJSON []byte, password string) (acc Account, err error) {
var key *Key
key, err = importPreSaleKey(am.keyStore, keyJSON, password)
if err != nil {
return
}
return Account{Address: key.Address}, nil
}
