-
Notifications
You must be signed in to change notification settings - Fork 20k
/
state_object.go
518 lines (466 loc) · 15 KB
/
state_object.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
// Copyright 2014 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 state
import (
"bytes"
"fmt"
"io"
"math/big"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/rlp"
)
var emptyCodeHash = crypto.Keccak256(nil)
type Code []byte
func (c Code) String() string {
return string(c) //strings.Join(Disassemble(c), " ")
}
type Storage map[common.Hash]common.Hash
func (s Storage) String() (str string) {
for key, value := range s {
str += fmt.Sprintf("%X : %X\n", key, value)
}
return
}
func (s Storage) Copy() Storage {
cpy := make(Storage)
for key, value := range s {
cpy[key] = value
}
return cpy
}
// stateObject represents an Ethereum account which is being modified.
//
// The usage pattern is as follows:
// First you need to obtain a state object.
// Account values can be accessed and modified through the object.
// Finally, call CommitTrie to write the modified storage trie into a database.
type stateObject struct {
address common.Address
addrHash common.Hash // hash of ethereum address of the account
data Account
db *StateDB
// DB error.
// State objects are used by the consensus core and VM which are
// unable to deal with database-level errors. Any error that occurs
// during a database read is memoized here and will eventually be returned
// by StateDB.Commit.
dbErr error
// Write caches.
trie Trie // storage trie, which becomes non-nil on first access
code Code // contract bytecode, which gets set when code is loaded
originStorage Storage // Storage cache of original entries to dedup rewrites, reset for every transaction
pendingStorage Storage // Storage entries that need to be flushed to disk, at the end of an entire block
dirtyStorage Storage // Storage entries that have been modified in the current transaction execution
fakeStorage Storage // Fake storage which constructed by caller for debugging purpose.
// Cache flags.
// When an object is marked suicided it will be delete from the trie
// during the "update" phase of the state transition.
dirtyCode bool // true if the code was updated
suicided bool
deleted bool
}
// empty returns whether the account is considered empty.
func (s *stateObject) empty() bool {
return s.data.Nonce == 0 && s.data.Balance.Sign() == 0 && bytes.Equal(s.data.CodeHash, emptyCodeHash)
}
// Account is the Ethereum consensus representation of accounts.
// These objects are stored in the main account trie.
type Account struct {
Nonce uint64
Balance *big.Int
Root common.Hash // merkle root of the storage trie
CodeHash []byte
}
// newObject creates a state object.
func newObject(db *StateDB, address common.Address, data Account) *stateObject {
if data.Balance == nil {
data.Balance = new(big.Int)
}
if data.CodeHash == nil {
data.CodeHash = emptyCodeHash
}
if data.Root == (common.Hash{}) {
data.Root = emptyRoot
}
return &stateObject{
db: db,
address: address,
addrHash: crypto.Keccak256Hash(address[:]),
data: data,
originStorage: make(Storage),
pendingStorage: make(Storage),
dirtyStorage: make(Storage),
}
}
// EncodeRLP implements rlp.Encoder.
func (s *stateObject) EncodeRLP(w io.Writer) error {
return rlp.Encode(w, s.data)
}
// setError remembers the first non-nil error it is called with.
func (s *stateObject) setError(err error) {
if s.dbErr == nil {
s.dbErr = err
}
}
func (s *stateObject) markSuicided() {
s.suicided = true
}
func (s *stateObject) touch() {
s.db.journal.append(touchChange{
account: &s.address,
})
if s.address == ripemd {
// Explicitly put it in the dirty-cache, which is otherwise generated from
// flattened journals.
s.db.journal.dirty(s.address)
}
}
func (s *stateObject) getTrie(db Database) Trie {
if s.trie == nil {
var err error
s.trie, err = db.OpenStorageTrie(s.addrHash, s.data.Root)
if err != nil {
s.trie, _ = db.OpenStorageTrie(s.addrHash, common.Hash{})
s.setError(fmt.Errorf("can't create storage trie: %v", err))
}
}
return s.trie
}
// GetState retrieves a value from the account storage trie.
func (s *stateObject) GetState(db Database, key common.Hash) common.Hash {
// If the fake storage is set, only lookup the state here(in the debugging mode)
if s.fakeStorage != nil {
return s.fakeStorage[key]
}
// If we have a dirty value for this state entry, return it
value, dirty := s.dirtyStorage[key]
if dirty {
return value
}
// Otherwise return the entry's original value
return s.GetCommittedState(db, key)
}
// GetCommittedState retrieves a value from the committed account storage trie.
func (s *stateObject) GetCommittedState(db Database, key common.Hash) common.Hash {
// If the fake storage is set, only lookup the state here(in the debugging mode)
if s.fakeStorage != nil {
return s.fakeStorage[key]
}
// If we have a pending write or clean cached, return that
if value, pending := s.pendingStorage[key]; pending {
return value
}
if value, cached := s.originStorage[key]; cached {
return value
}
// If no live objects are available, attempt to use snapshots
var (
enc []byte
err error
)
if s.db.snap != nil {
if metrics.EnabledExpensive {
defer func(start time.Time) { s.db.SnapshotStorageReads += time.Since(start) }(time.Now())
}
// If the object was destructed in *this* block (and potentially resurrected),
// the storage has been cleared out, and we should *not* consult the previous
// snapshot about any storage values. The only possible alternatives are:
// 1) resurrect happened, and new slot values were set -- those should
// have been handles via pendingStorage above.
// 2) we don't have new values, and can deliver empty response back
if _, destructed := s.db.snapDestructs[s.addrHash]; destructed {
return common.Hash{}
}
enc, err = s.db.snap.Storage(s.addrHash, crypto.Keccak256Hash(key.Bytes()))
}
// If snapshot unavailable or reading from it failed, load from the database
if s.db.snap == nil || err != nil {
if metrics.EnabledExpensive {
defer func(start time.Time) { s.db.StorageReads += time.Since(start) }(time.Now())
}
if enc, err = s.getTrie(db).TryGet(key.Bytes()); err != nil {
s.setError(err)
return common.Hash{}
}
}
var value common.Hash
if len(enc) > 0 {
_, content, _, err := rlp.Split(enc)
if err != nil {
s.setError(err)
}
value.SetBytes(content)
}
s.originStorage[key] = value
return value
}
// SetState updates a value in account storage.
func (s *stateObject) SetState(db Database, key, value common.Hash) {
// If the fake storage is set, put the temporary state update here.
if s.fakeStorage != nil {
s.fakeStorage[key] = value
return
}
// If the new value is the same as old, don't set
prev := s.GetState(db, key)
if prev == value {
return
}
// New value is different, update and journal the change
s.db.journal.append(storageChange{
account: &s.address,
key: key,
prevalue: prev,
})
s.setState(key, value)
}
// SetStorage replaces the entire state storage with the given one.
//
// After this function is called, all original state will be ignored and state
// lookup only happens in the fake state storage.
//
// Note this function should only be used for debugging purpose.
func (s *stateObject) SetStorage(storage map[common.Hash]common.Hash) {
// Allocate fake storage if it's nil.
if s.fakeStorage == nil {
s.fakeStorage = make(Storage)
}
for key, value := range storage {
s.fakeStorage[key] = value
}
// Don't bother journal since this function should only be used for
// debugging and the `fake` storage won't be committed to database.
}
func (s *stateObject) setState(key, value common.Hash) {
s.dirtyStorage[key] = value
}
// finalise moves all dirty storage slots into the pending area to be hashed or
// committed later. It is invoked at the end of every transaction.
func (s *stateObject) finalise() {
for key, value := range s.dirtyStorage {
s.pendingStorage[key] = value
}
if len(s.dirtyStorage) > 0 {
s.dirtyStorage = make(Storage)
}
}
// updateTrie writes cached storage modifications into the object's storage trie.
// It will return nil if the trie has not been loaded and no changes have been made
func (s *stateObject) updateTrie(db Database) Trie {
// Make sure all dirty slots are finalized into the pending storage area
s.finalise()
if len(s.pendingStorage) == 0 {
return s.trie
}
// Track the amount of time wasted on updating the storge trie
if metrics.EnabledExpensive {
defer func(start time.Time) { s.db.StorageUpdates += time.Since(start) }(time.Now())
}
// Retrieve the snapshot storage map for the object
var storage map[common.Hash][]byte
if s.db.snap != nil {
// Retrieve the old storage map, if available, create a new one otherwise
storage = s.db.snapStorage[s.addrHash]
if storage == nil {
storage = make(map[common.Hash][]byte)
s.db.snapStorage[s.addrHash] = storage
}
}
// Insert all the pending updates into the trie
tr := s.getTrie(db)
for key, value := range s.pendingStorage {
// Skip noop changes, persist actual changes
if value == s.originStorage[key] {
continue
}
s.originStorage[key] = value
var v []byte
if (value == common.Hash{}) {
s.setError(tr.TryDelete(key[:]))
} else {
// Encoding []byte cannot fail, ok to ignore the error.
v, _ = rlp.EncodeToBytes(common.TrimLeftZeroes(value[:]))
s.setError(tr.TryUpdate(key[:], v))
}
// If state snapshotting is active, cache the data til commit
if storage != nil {
storage[crypto.Keccak256Hash(key[:])] = v // v will be nil if value is 0x00
}
}
if len(s.pendingStorage) > 0 {
s.pendingStorage = make(Storage)
}
return tr
}
// UpdateRoot sets the trie root to the current root hash of
func (s *stateObject) updateRoot(db Database) {
// If nothing changed, don't bother with hashing anything
if s.updateTrie(db) == nil {
return
}
// Track the amount of time wasted on hashing the storge trie
if metrics.EnabledExpensive {
defer func(start time.Time) { s.db.StorageHashes += time.Since(start) }(time.Now())
}
s.data.Root = s.trie.Hash()
}
// CommitTrie the storage trie of the object to db.
// This updates the trie root.
func (s *stateObject) CommitTrie(db Database) error {
// If nothing changed, don't bother with hashing anything
if s.updateTrie(db) == nil {
return nil
}
if s.dbErr != nil {
return s.dbErr
}
// Track the amount of time wasted on committing the storge trie
if metrics.EnabledExpensive {
defer func(start time.Time) { s.db.StorageCommits += time.Since(start) }(time.Now())
}
root, err := s.trie.Commit(nil)
if err == nil {
s.data.Root = root
}
return err
}
// AddBalance adds amount to s's balance.
// It is used to add funds to the destination account of a transfer.
func (s *stateObject) AddBalance(amount *big.Int) {
// EIP161: We must check emptiness for the objects such that the account
// clearing (0,0,0 objects) can take effect.
if amount.Sign() == 0 {
if s.empty() {
s.touch()
}
return
}
s.SetBalance(new(big.Int).Add(s.Balance(), amount))
}
// SubBalance removes amount from s's balance.
// It is used to remove funds from the origin account of a transfer.
func (s *stateObject) SubBalance(amount *big.Int) {
if amount.Sign() == 0 {
return
}
s.SetBalance(new(big.Int).Sub(s.Balance(), amount))
}
func (s *stateObject) SetBalance(amount *big.Int) {
s.db.journal.append(balanceChange{
account: &s.address,
prev: new(big.Int).Set(s.data.Balance),
})
s.setBalance(amount)
}
func (s *stateObject) setBalance(amount *big.Int) {
s.data.Balance = amount
}
// Return the gas back to the origin. Used by the Virtual machine or Closures
func (s *stateObject) ReturnGas(gas *big.Int) {}
func (s *stateObject) deepCopy(db *StateDB) *stateObject {
stateObject := newObject(db, s.address, s.data)
if s.trie != nil {
stateObject.trie = db.db.CopyTrie(s.trie)
}
stateObject.code = s.code
stateObject.dirtyStorage = s.dirtyStorage.Copy()
stateObject.originStorage = s.originStorage.Copy()
stateObject.pendingStorage = s.pendingStorage.Copy()
stateObject.suicided = s.suicided
stateObject.dirtyCode = s.dirtyCode
stateObject.deleted = s.deleted
return stateObject
}
//
// Attribute accessors
//
// Returns the address of the contract/account
func (s *stateObject) Address() common.Address {
return s.address
}
// Code returns the contract code associated with this object, if any.
func (s *stateObject) Code(db Database) []byte {
if s.code != nil {
return s.code
}
if bytes.Equal(s.CodeHash(), emptyCodeHash) {
return nil
}
code, err := db.ContractCode(s.addrHash, common.BytesToHash(s.CodeHash()))
if err != nil {
s.setError(fmt.Errorf("can't load code hash %x: %v", s.CodeHash(), err))
}
s.code = code
return code
}
// CodeSize returns the size of the contract code associated with this object,
// or zero if none. This method is an almost mirror of Code, but uses a cache
// inside the database to avoid loading codes seen recently.
func (s *stateObject) CodeSize(db Database) int {
if s.code != nil {
return len(s.code)
}
if bytes.Equal(s.CodeHash(), emptyCodeHash) {
return 0
}
size, err := db.ContractCodeSize(s.addrHash, common.BytesToHash(s.CodeHash()))
if err != nil {
s.setError(fmt.Errorf("can't load code size %x: %v", s.CodeHash(), err))
}
return size
}
func (s *stateObject) SetCode(codeHash common.Hash, code []byte) {
prevcode := s.Code(s.db.db)
s.db.journal.append(codeChange{
account: &s.address,
prevhash: s.CodeHash(),
prevcode: prevcode,
})
s.setCode(codeHash, code)
}
func (s *stateObject) setCode(codeHash common.Hash, code []byte) {
s.code = code
s.data.CodeHash = codeHash[:]
s.dirtyCode = true
}
func (s *stateObject) SetNonce(nonce uint64) {
s.db.journal.append(nonceChange{
account: &s.address,
prev: s.data.Nonce,
})
s.setNonce(nonce)
}
func (s *stateObject) setNonce(nonce uint64) {
s.data.Nonce = nonce
}
func (s *stateObject) CodeHash() []byte {
return s.data.CodeHash
}
func (s *stateObject) Balance() *big.Int {
return s.data.Balance
}
func (s *stateObject) Nonce() uint64 {
return s.data.Nonce
}
// Never called, but must be present to allow stateObject to be used
// as a vm.Account interface that also satisfies the vm.ContractRef
// interface. Interfaces are awesome.
func (s *stateObject) Value() *big.Int {
panic("Value on stateObject should never be called")
}