1package statedb
  2
  3import (
  4	"errors"
  5	"fmt"
  6	"math/big"
  7
  8	"github.com/hermeznetwork/hermez-node/common"
  9	"github.com/hermeznetwork/hermez-node/db/kvdb"
 10	"github.com/hermeznetwork/hermez-node/log"
 11	"github.com/hermeznetwork/tracerr"
 12	"github.com/iden3/go-merkletree"
 13	"github.com/iden3/go-merkletree/db"
 14	"github.com/iden3/go-merkletree/db/pebble"
 15)
 16
 17var (
 18	// ErrStateDBWithoutMT is used when a method that requires a MerkleTree
 19	// is called in a StateDB that does not have a MerkleTree defined
 20	ErrStateDBWithoutMT = errors.New("Can not call method to use MerkleTree in a StateDB without MerkleTree")
 21
 22	// ErrAccountAlreadyExists is used when CreateAccount is called and the
 23	// Account already exists
 24	ErrAccountAlreadyExists = errors.New("Can not CreateAccount because Account already exists")
 25
 26	// ErrIdxNotFound is used when trying to get the Idx from EthAddr or
 27	// EthAddr&ToBJJ
 28	ErrIdxNotFound = errors.New("Idx can not be found")
 29	// ErrGetIdxNoCase is used when trying to get the Idx from EthAddr &
 30	// BJJ with not compatible combination
 31	ErrGetIdxNoCase = errors.New("Can not get Idx due unexpected combination of ethereum Address & BabyJubJub PublicKey")
 32
 33	// PrefixKeyIdx is the key prefix for idx in the db
 34	PrefixKeyIdx = []byte("i:")
 35	// PrefixKeyAccHash is the key prefix for account hash in the db
 36	PrefixKeyAccHash = []byte("h:")
 37	// PrefixKeyMT is the key prefix for merkle tree in the db
 38	PrefixKeyMT = []byte("m:")
 39	// PrefixKeyAddr is the key prefix for address in the db
 40	PrefixKeyAddr = []byte("a:")
 41	// PrefixKeyAddrBJJ is the key prefix for address-babyjubjub in the db
 42	PrefixKeyAddrBJJ = []byte("ab:")
 43)
 44
 45const (
 46	// TypeSynchronizer defines a StateDB used by the Synchronizer, that
 47	// generates the ExitTree when processing the txs
 48	TypeSynchronizer = "synchronizer"
 49	// TypeTxSelector defines a StateDB used by the TxSelector, without
 50	// computing ExitTree neither the ZKInputs
 51	TypeTxSelector = "txselector"
 52	// TypeBatchBuilder defines a StateDB used by the BatchBuilder, that
 53	// generates the ExitTree and the ZKInput when processing the txs
 54	TypeBatchBuilder = "batchbuilder"
 55)
 56
 57// TypeStateDB determines the type of StateDB
 58type TypeStateDB string
 59
 60// StateDB represents the StateDB object
 61type StateDB struct {
 62	path    string
 63	Typ     TypeStateDB
 64	db      *kvdb.KVDB
 65	nLevels int
 66	MT      *merkletree.MerkleTree
 67	keep    int
 68}
 69
 70// Last offers a subset of view methods of the StateDB that can be
 71// called via the LastRead method of StateDB in a thread-safe manner to obtain
 72// a consistent view to the last batch of the StateDB.
 73type Last struct {
 74	db db.Storage
 75}
 76
 77// GetAccount returns the account for the given Idx
 78func (s *Last) GetAccount(idx common.Idx) (*common.Account, error) {
 79	return GetAccountInTreeDB(s.db, idx)
 80}
 81
 82// GetCurrentBatch returns the current BatchNum stored in Last.db
 83func (s *Last) GetCurrentBatch() (common.BatchNum, error) {
 84	cbBytes, err := s.db.Get(kvdb.KeyCurrentBatch)
 85	if tracerr.Unwrap(err) == db.ErrNotFound {
 86		return 0, nil
 87	} else if err != nil {
 88		return 0, tracerr.Wrap(err)
 89	}
 90	return common.BatchNumFromBytes(cbBytes)
 91}
 92
 93// DB returns the underlying storage of Last
 94func (s *Last) DB() db.Storage {
 95	return s.db
 96}
 97
 98// GetAccounts returns all the accounts in the db.  Use for debugging pruposes
 99// only.
100func (s *Last) GetAccounts() ([]common.Account, error) {
101	return getAccounts(s.db)
102}
103
104// NewStateDB creates a new StateDB, allowing to use an in-memory or in-disk
105// storage.  Checkpoints older than the value defined by `keep` will be
106// deleted.
107func NewStateDB(pathDB string, keep int, typ TypeStateDB, nLevels int) (*StateDB, error) {
108	var kv *kvdb.KVDB
109	var err error
110
111	kv, err = kvdb.NewKVDB(pathDB, keep)
112	if err != nil {
113		return nil, tracerr.Wrap(err)
114	}
115
116	var mt *merkletree.MerkleTree = nil
117	if typ == TypeSynchronizer || typ == TypeBatchBuilder {
118		mt, err = merkletree.NewMerkleTree(kv.StorageWithPrefix(PrefixKeyMT), nLevels)
119		if err != nil {
120			return nil, tracerr.Wrap(err)
121		}
122	}
123	if typ == TypeTxSelector && nLevels != 0 {
124		return nil, tracerr.Wrap(fmt.Errorf("invalid StateDB parameters: StateDB type==TypeStateDB can not have nLevels!=0"))
125	}
126
127	return &StateDB{
128		path:    pathDB,
129		db:      kv,
130		nLevels: nLevels,
131		MT:      mt,
132		Typ:     typ,
133		keep:    keep,
134	}, nil
135}
136
137// LastRead is a thread-safe method to query the last checkpoint of the StateDB
138// via the Last type methods
139func (s *StateDB) LastRead(fn func(sdbLast *Last) error) error {
140	return s.db.LastRead(
141		func(db *pebble.Storage) error {
142			return fn(&Last{
143				db: db,
144			})
145		},
146	)
147}
148
149// LastGetAccount is a thread-safe method to query an account in the last
150// checkpoint of the StateDB.
151func (s *StateDB) LastGetAccount(idx common.Idx) (*common.Account, error) {
152	var account *common.Account
153	if err := s.LastRead(func(sdb *Last) error {
154		var err error
155		account, err = sdb.GetAccount(idx)
156		return err
157	}); err != nil {
158		return nil, tracerr.Wrap(err)
159	}
160	return account, nil
161}
162
163// LastGetCurrentBatch is a thread-safe method to get the current BatchNum in
164// the last checkpoint of the StateDB.
165func (s *StateDB) LastGetCurrentBatch() (common.BatchNum, error) {
166	var batchNum common.BatchNum
167	if err := s.LastRead(func(sdb *Last) error {
168		var err error
169		batchNum, err = sdb.GetCurrentBatch()
170		return err
171	}); err != nil {
172		return 0, tracerr.Wrap(err)
173	}
174	return batchNum, nil
175}
176
177// LastMTGetRoot returns the root of the underlying Merkle Tree in the last
178// checkpoint of the StateDB.
179func (s *StateDB) LastMTGetRoot() (*big.Int, error) {
180	var root *big.Int
181	if err := s.LastRead(func(sdb *Last) error {
182		mt, err := merkletree.NewMerkleTree(sdb.DB().WithPrefix(PrefixKeyMT), s.nLevels)
183		if err != nil {
184			return tracerr.Wrap(err)
185		}
186		root = mt.Root().BigInt()
187		return nil
188	}); err != nil {
189		return nil, tracerr.Wrap(err)
190	}
191	return root, nil
192}
193
194// MakeCheckpoint does a checkpoint at the given batchNum in the defined path.
195// Internally this advances & stores the current BatchNum, and then stores a
196// Checkpoint of the current state of the StateDB.
197func (s *StateDB) MakeCheckpoint() error {
198	log.Debugw("Making StateDB checkpoint", "batch", s.CurrentBatch()+1, "type", s.Typ)
199	return s.db.MakeCheckpoint()
200}
201
202// CurrentBatch returns the current in-memory CurrentBatch of the StateDB.db
203func (s *StateDB) CurrentBatch() common.BatchNum {
204	return s.db.CurrentBatch
205}
206
207// CurrentIdx returns the current in-memory CurrentIdx of the StateDB.db
208func (s *StateDB) CurrentIdx() common.Idx {
209	return s.db.CurrentIdx
210}
211
212// getCurrentBatch returns the current BatchNum stored in the StateDB.db
213func (s *StateDB) getCurrentBatch() (common.BatchNum, error) {
214	return s.db.GetCurrentBatch()
215}
216
217// GetCurrentIdx returns the stored Idx from the localStateDB, which is the
218// last Idx used for an Account in the localStateDB.
219func (s *StateDB) GetCurrentIdx() (common.Idx, error) {
220	return s.db.GetCurrentIdx()
221}
222
223// SetCurrentIdx stores Idx in the StateDB
224func (s *StateDB) SetCurrentIdx(idx common.Idx) error {
225	return s.db.SetCurrentIdx(idx)
226}
227
228// Reset resets the StateDB to the checkpoint at the given batchNum. Reset
229// does not delete the checkpoints between old current and the new current,
230// those checkpoints will remain in the storage, and eventually will be
231// deleted when MakeCheckpoint overwrites them.
232func (s *StateDB) Reset(batchNum common.BatchNum) error {
233	err := s.db.Reset(batchNum)
234	if err != nil {
235		return tracerr.Wrap(err)
236	}
237	if s.MT != nil {
238		// open the MT for the current s.db
239		mt, err := merkletree.NewMerkleTree(s.db.StorageWithPrefix(PrefixKeyMT), s.MT.MaxLevels())
240		if err != nil {
241			return tracerr.Wrap(err)
242		}
243		s.MT = mt
244	}
245	log.Debugw("Making StateDB Reset", "batch", batchNum)
246	return nil
247}
248
249// GetAccount returns the account for the given Idx
250func (s *StateDB) GetAccount(idx common.Idx) (*common.Account, error) {
251	return GetAccountInTreeDB(s.db.DB(), idx)
252}
253
254func accountsIter(db db.Storage, fn func(a *common.Account) (bool, error)) error {
255	idxDB := db.WithPrefix(PrefixKeyIdx)
256	if err := idxDB.Iterate(func(k []byte, v []byte) (bool, error) {
257		idx, err := common.IdxFromBytes(k)
258		if err != nil {
259			return false, tracerr.Wrap(err)
260		}
261		acc, err := GetAccountInTreeDB(db, idx)
262		if err != nil {
263			return false, tracerr.Wrap(err)
264		}
265		ok, err := fn(acc)
266		if err != nil {
267			return false, tracerr.Wrap(err)
268		}
269		return ok, nil
270	}); err != nil {
271		return tracerr.Wrap(err)
272	}
273	return nil
274}
275
276func getAccounts(db db.Storage) ([]common.Account, error) {
277	accs := []common.Account{}
278	if err := accountsIter(
279		db,
280		func(a *common.Account) (bool, error) {
281			accs = append(accs, *a)
282			return true, nil
283		},
284	); err != nil {
285		return nil, tracerr.Wrap(err)
286	}
287	return accs, nil
288}
289
290// TestGetAccounts returns all the accounts in the db.  Use only in tests.
291// Outside tests getting all the accounts is discouraged because it's an
292// expensive operation, but if you must do it, use `LastRead()` method to get a
293// thread-safe and consistent view of the stateDB.
294func (s *StateDB) TestGetAccounts() ([]common.Account, error) {
295	return getAccounts(s.db.DB())
296}
297
298// GetAccountInTreeDB is abstracted from StateDB to be used from StateDB and
299// from ExitTree.  GetAccount returns the account for the given Idx
300func GetAccountInTreeDB(sto db.Storage, idx common.Idx) (*common.Account, error) {
301	idxBytes, err := idx.Bytes()
302	if err != nil {
303		return nil, tracerr.Wrap(err)
304	}
305	vBytes, err := sto.Get(append(PrefixKeyIdx, idxBytes[:]...))
306	if err != nil {
307		return nil, tracerr.Wrap(err)
308	}
309	accBytes, err := sto.Get(append(PrefixKeyAccHash, vBytes...))
310	if err != nil {
311		return nil, tracerr.Wrap(err)
312	}
313	var b [32 * common.NLeafElems]byte
314	copy(b[:], accBytes)
315	account, err := common.AccountFromBytes(b)
316	if err != nil {
317		return nil, tracerr.Wrap(err)
318	}
319	account.Idx = idx
320	return account, nil
321}
322
323// CreateAccount creates a new Account in the StateDB for the given Idx.  If
324// StateDB.MT==nil, MerkleTree is not affected, otherwise updates the
325// MerkleTree, returning a CircomProcessorProof.
326func (s *StateDB) CreateAccount(idx common.Idx, account *common.Account) (*merkletree.CircomProcessorProof, error) {
327	cpp, err := CreateAccountInTreeDB(s.db.DB(), s.MT, idx, account)
328	if err != nil {
329		return cpp, tracerr.Wrap(err)
330	}
331	// store idx by EthAddr & BJJ
332	err = s.setIdxByEthAddrBJJ(idx, account.EthAddr, account.BJJ, account.TokenID)
333	return cpp, tracerr.Wrap(err)
334}
335
336// CreateAccountInTreeDB is abstracted from StateDB to be used from StateDB and
337// from ExitTree.  Creates a new Account in the StateDB for the given Idx.  If
338// StateDB.MT==nil, MerkleTree is not affected, otherwise updates the
339// MerkleTree, returning a CircomProcessorProof.
340func CreateAccountInTreeDB(sto db.Storage, mt *merkletree.MerkleTree, idx common.Idx, account *common.Account) (*merkletree.CircomProcessorProof, error) {
341	// store at the DB the key: v, and value: leaf.Bytes()
342	v, err := account.HashValue()
343	if err != nil {
344		return nil, tracerr.Wrap(err)
345	}
346	accountBytes, err := account.Bytes()
347	if err != nil {
348		return nil, tracerr.Wrap(err)
349	}
350
351	// store the Leaf value
352	tx, err := sto.NewTx()
353	if err != nil {
354		return nil, tracerr.Wrap(err)
355	}
356
357	idxBytes, err := idx.Bytes()
358	if err != nil {
359		return nil, tracerr.Wrap(err)
360	}
361	_, err = tx.Get(append(PrefixKeyIdx, idxBytes[:]...))
362	if tracerr.Unwrap(err) != db.ErrNotFound {
363		return nil, tracerr.Wrap(ErrAccountAlreadyExists)
364	}
365
366	err = tx.Put(append(PrefixKeyAccHash, v.Bytes()...), accountBytes[:])
367	if err != nil {
368		return nil, tracerr.Wrap(err)
369	}
370	err = tx.Put(append(PrefixKeyIdx, idxBytes[:]...), v.Bytes())
371	if err != nil {
372		return nil, tracerr.Wrap(err)
373	}
374
375	if err := tx.Commit(); err != nil {
376		return nil, tracerr.Wrap(err)
377	}
378
379	if mt != nil {
380		return mt.AddAndGetCircomProof(idx.BigInt(), v)
381	}
382
383	return nil, nil
384}
385
386// UpdateAccount updates the Account in the StateDB for the given Idx.  If
387// StateDB.mt==nil, MerkleTree is not affected, otherwise updates the
388// MerkleTree, returning a CircomProcessorProof.
389func (s *StateDB) UpdateAccount(idx common.Idx, account *common.Account) (*merkletree.CircomProcessorProof, error) {
390	return UpdateAccountInTreeDB(s.db.DB(), s.MT, idx, account)
391}
392
393// UpdateAccountInTreeDB is abstracted from StateDB to be used from StateDB and
394// from ExitTree.  Updates the Account in the StateDB for the given Idx.  If
395// StateDB.mt==nil, MerkleTree is not affected, otherwise updates the
396// MerkleTree, returning a CircomProcessorProof.
397func UpdateAccountInTreeDB(sto db.Storage, mt *merkletree.MerkleTree, idx common.Idx, account *common.Account) (*merkletree.CircomProcessorProof, error) {
398	// store at the DB the key: v, and value: account.Bytes()
399	v, err := account.HashValue()
400	if err != nil {
401		return nil, tracerr.Wrap(err)
402	}
403	accountBytes, err := account.Bytes()
404	if err != nil {
405		return nil, tracerr.Wrap(err)
406	}
407
408	tx, err := sto.NewTx()
409	if err != nil {
410		return nil, tracerr.Wrap(err)
411	}
412	err = tx.Put(append(PrefixKeyAccHash, v.Bytes()...), accountBytes[:])
413	if err != nil {
414		return nil, tracerr.Wrap(err)
415	}
416	idxBytes, err := idx.Bytes()
417	if err != nil {
418		return nil, tracerr.Wrap(err)
419	}
420	err = tx.Put(append(PrefixKeyIdx, idxBytes[:]...), v.Bytes())
421	if err != nil {
422		return nil, tracerr.Wrap(err)
423	}
424
425	if err := tx.Commit(); err != nil {
426		return nil, tracerr.Wrap(err)
427	}
428
429	if mt != nil {
430		proof, err := mt.Update(idx.BigInt(), v)
431		return proof, tracerr.Wrap(err)
432	}
433	return nil, nil
434}
435
436// MTGetProof returns the CircomVerifierProof for a given Idx
437func (s *StateDB) MTGetProof(idx common.Idx) (*merkletree.CircomVerifierProof, error) {
438	if s.MT == nil {
439		return nil, tracerr.Wrap(ErrStateDBWithoutMT)
440	}
441	p, err := s.MT.GenerateSCVerifierProof(idx.BigInt(), s.MT.Root())
442	if err != nil {
443		return nil, tracerr.Wrap(err)
444	}
445	return p, nil
446}
447
448// Close the StateDB
449func (s *StateDB) Close() {
450	s.db.Close()
451}
452
453// LocalStateDB represents the local StateDB which allows to make copies from
454// the synchronizer StateDB, and is used by the tx-selector and the
455// batch-builder. LocalStateDB is an in-memory storage.
456type LocalStateDB struct {
457	*StateDB
458	synchronizerStateDB *StateDB
459}
460
461// NewLocalStateDB returns a new LocalStateDB connected to the given
462// synchronizerDB.  Checkpoints older than the value defined by `keep` will be
463// deleted.
464func NewLocalStateDB(path string, keep int, synchronizerDB *StateDB, typ TypeStateDB,
465	nLevels int) (*LocalStateDB, error) {
466	s, err := NewStateDB(path, keep, typ, nLevels)
467	if err != nil {
468		return nil, tracerr.Wrap(err)
469	}
470	return &LocalStateDB{
471		s,
472		synchronizerDB,
473	}, nil
474}
475
476// Reset performs a reset in the LocaStateDB. If fromSynchronizer is true, it
477// gets the state from LocalStateDB.synchronizerStateDB for the given batchNum.
478// If fromSynchronizer is false, get the state from LocalStateDB checkpoints.
479func (l *LocalStateDB) Reset(batchNum common.BatchNum, fromSynchronizer bool) error {
480	if fromSynchronizer {
481		err := l.db.ResetFromSynchronizer(batchNum, l.synchronizerStateDB.db)
482		if err != nil {
483			return tracerr.Wrap(err)
484		}
485		// open the MT for the current s.db
486		if l.MT != nil {
487			mt, err := merkletree.NewMerkleTree(l.db.StorageWithPrefix(PrefixKeyMT), l.MT.MaxLevels())
488			if err != nil {
489				return tracerr.Wrap(err)
490			}
491			l.MT = mt
492		}
493		return nil
494	}
495	// use checkpoint from LocalStateDB
496	return l.StateDB.Reset(batchNum)
497}