hermez-node/db/statedb/txprocessors.go
db/statedb/txprocessors.goRaw
1package statedb
2
3import (
4 "errors"
5 "io/ioutil"
6 "math/big"
7 "os"
8
9 "github.com/hermeznetwork/hermez-node/common"
10 "github.com/hermeznetwork/hermez-node/log"
11 "github.com/iden3/go-iden3-crypto/babyjub"
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 // keyidx is used as key in the db to store the current Idx
19 keyidx = []byte("k:idx")
20)
21
22func (s *StateDB) resetZKInputs() {
23 s.zki = nil
24 s.i = 0
25}
26
27type processedExit struct {
28 exit bool
29 newExit bool
30 idx common.Idx
31 acc common.Account
32}
33
34// ProcessTxs process the given L1Txs & L2Txs applying the needed updates to
35// the StateDB depending on the transaction Type. If StateDB
36// type==TypeBatchBuilder, returns the common.ZKInputs to generate the
37// SnarkProof later used by the BatchBuilder. If StateDB
38// type==TypeSynchronizer, assumes that the call is done from the Synchronizer,
39// returns common.ExitTreeLeaf that is later used by the Synchronizer to update
40// the HistoryDB, and adds Nonce & TokenID to the L2Txs.
41func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []common.L1Tx, l2txs []common.PoolL2Tx) (*common.ZKInputs, []common.ExitInfo, error) {
42 var err error
43 var exitTree *merkletree.MerkleTree
44
45 if s.zki != nil {
46 return nil, nil, errors.New("Expected StateDB.zki==nil, something went wrong and it's not empty")
47 }
48 defer s.resetZKInputs()
49
50 nTx := len(l1usertxs) + len(l1coordinatortxs) + len(l2txs)
51 if nTx == 0 {
52 // TODO return ZKInputs of batch without txs
53 return nil, nil, nil
54 }
55 exits := make([]processedExit, nTx)
56
57 if s.typ == TypeBatchBuilder {
58 s.zki = common.NewZKInputs(nTx, 24, 32) // TODO this values will be parameters of the function, taken from config file/coordinator call
59 s.zki.OldLastIdx = (s.idx - 1).BigInt()
60 s.zki.OldStateRoot = s.mt.Root().BigInt()
61 }
62
63 // TBD if ExitTree is only in memory or stored in disk, for the moment
64 // only needed in memory
65 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
66 tmpDir, err := ioutil.TempDir("", "hermez-statedb-exittree")
67 if err != nil {
68 return nil, nil, err
69 }
70 defer func() {
71 if err := os.RemoveAll(tmpDir); err != nil {
72 log.Errorw("Deleting statedb temp exit tree", "err", err)
73 }
74 }()
75 sto, err := pebble.NewPebbleStorage(tmpDir, false)
76 if err != nil {
77 return nil, nil, err
78 }
79 exitTree, err = merkletree.NewMerkleTree(sto, s.mt.MaxLevels())
80 if err != nil {
81 return nil, nil, err
82 }
83 }
84
85 // assumption: l1usertx are sorted by L1Tx.Position
86 for i := 0; i < len(l1usertxs); i++ {
87 exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, &l1usertxs[i])
88 if err != nil {
89 return nil, nil, err
90 }
91 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
92 if exitIdx != nil && exitTree != nil {
93 exits[s.i] = processedExit{
94 exit: true,
95 newExit: newExit,
96 idx: *exitIdx,
97 acc: *exitAccount,
98 }
99 }
100 s.i++
101 }
102 }
103 for i := 0; i < len(l1coordinatortxs); i++ {
104 exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, &l1coordinatortxs[i])
105 if err != nil {
106 return nil, nil, err
107 }
108 if exitIdx != nil {
109 log.Error("Unexpected Exit in L1CoordinatorTx")
110 }
111 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
112 if exitIdx != nil && exitTree != nil {
113 exits[s.i] = processedExit{
114 exit: true,
115 newExit: newExit,
116 idx: *exitIdx,
117 acc: *exitAccount,
118 }
119 }
120 s.i++
121 }
122 }
123 for i := 0; i < len(l2txs); i++ {
124 exitIdx, exitAccount, newExit, err := s.processL2Tx(exitTree, &l2txs[i])
125 if err != nil {
126 return nil, nil, err
127 }
128 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
129 if exitIdx != nil && exitTree != nil {
130 exits[s.i] = processedExit{
131 exit: true,
132 newExit: newExit,
133 idx: *exitIdx,
134 acc: *exitAccount,
135 }
136 }
137 s.i++
138 }
139 }
140
141 if s.typ == TypeTxSelector {
142 return nil, nil, nil
143 }
144
145 // once all txs processed (exitTree root frozen), for each Exit,
146 // generate common.ExitInfo data
147 var exitInfos []common.ExitInfo
148 for i := 0; i < nTx; i++ {
149 if !exits[i].exit {
150 continue
151 }
152 exitIdx := exits[i].idx
153 exitAccount := exits[i].acc
154
155 // 0. generate MerkleProof
156 p, err := exitTree.GenerateCircomVerifierProof(exitIdx.BigInt(), nil)
157 if err != nil {
158 return nil, nil, err
159 }
160 // 1. generate common.ExitInfo
161 ei := common.ExitInfo{
162 AccountIdx: exitIdx,
163 MerkleProof: p,
164 Balance: exitAccount.Balance,
165 }
166 exitInfos = append(exitInfos, ei)
167
168 if s.zki != nil {
169 s.zki.TokenID2[i] = exitAccount.TokenID.BigInt()
170 s.zki.Nonce2[i] = exitAccount.Nonce.BigInt()
171 if babyjub.PointCoordSign(exitAccount.PublicKey.X) {
172 s.zki.Sign2[i] = big.NewInt(1)
173 }
174 s.zki.Ay2[i] = exitAccount.PublicKey.Y
175 s.zki.Balance2[i] = exitAccount.Balance
176 s.zki.EthAddr2[i] = common.EthAddrToBigInt(exitAccount.EthAddr)
177 s.zki.Siblings2[i] = p.Siblings
178 if exits[i].newExit {
179 s.zki.NewExit[i] = big.NewInt(1)
180 }
181 if p.IsOld0 {
182 s.zki.IsOld0_2[i] = big.NewInt(1)
183 }
184 s.zki.OldKey2[i] = p.OldKey.BigInt()
185 s.zki.OldValue2[i] = p.OldValue.BigInt()
186 }
187 }
188 if s.typ == TypeSynchronizer {
189 return nil, exitInfos, nil
190 }
191
192 // compute last ZKInputs parameters
193 s.zki.GlobalChainID = big.NewInt(0) // TODO, 0: ethereum, this will be get from config file
194 // zki.FeeIdxs = ? // TODO, this will be get from the config file
195 tokenIDs, err := s.getTokenIDsBigInt(l1usertxs, l1coordinatortxs, l2txs)
196 if err != nil {
197 return nil, nil, err
198 }
199 s.zki.FeePlanTokens = tokenIDs
200
201 // s.zki.ISInitStateRootFee = s.mt.Root().BigInt()
202
203 // TODO once the Node Config sets the Accounts where to send the Fees
204 // compute fees & update ZKInputs
205
206 // return exitInfos, so Synchronizer will be able to store it into
207 // HistoryDB for the concrete BatchNum
208 return s.zki, exitInfos, nil
209}
210
211// getTokenIDsBigInt returns the list of TokenIDs in *big.Int format
212func (s *StateDB) getTokenIDsBigInt(l1usertxs, l1coordinatortxs []common.L1Tx, l2txs []common.PoolL2Tx) ([]*big.Int, error) {
213 tokenIDs := make(map[common.TokenID]bool)
214 for i := 0; i < len(l1usertxs); i++ {
215 tokenIDs[l1usertxs[i].TokenID] = true
216 }
217 for i := 0; i < len(l1coordinatortxs); i++ {
218 tokenIDs[l1coordinatortxs[i].TokenID] = true
219 }
220 for i := 0; i < len(l2txs); i++ {
221 // as L2Tx does not have parameter TokenID, get it from the
222 // AccountsDB (in the StateDB)
223 acc, err := s.GetAccount(l2txs[i].ToIdx)
224 if err != nil {
225 return nil, err
226 }
227 tokenIDs[acc.TokenID] = true
228 }
229 var tBI []*big.Int
230 for t := range tokenIDs {
231 tBI = append(tBI, t.BigInt())
232 }
233 return tBI, nil
234}
235
236// processL1Tx process the given L1Tx applying the needed updates to the
237// StateDB depending on the transaction Type. It returns the 3 parameters
238// related to the Exit (in case of): Idx, ExitAccount, boolean determining if
239// the Exit created a new Leaf in the ExitTree.
240func (s *StateDB) processL1Tx(exitTree *merkletree.MerkleTree, tx *common.L1Tx) (*common.Idx, *common.Account, bool, error) {
241 // ZKInputs
242 if s.zki != nil {
243 // Txs
244 // s.zki.TxCompressedData[s.i] = tx.TxCompressedData() // uncomment once L1Tx.TxCompressedData is ready
245 s.zki.FromIdx[s.i] = tx.FromIdx.BigInt()
246 s.zki.ToIdx[s.i] = tx.ToIdx.BigInt()
247 s.zki.OnChain[s.i] = big.NewInt(1)
248
249 // L1Txs
250 s.zki.LoadAmountF[s.i] = tx.LoadAmount
251 s.zki.FromEthAddr[s.i] = common.EthAddrToBigInt(tx.FromEthAddr)
252 if tx.FromBJJ != nil {
253 s.zki.FromBJJCompressed[s.i] = BJJCompressedTo256BigInts(tx.FromBJJ.Compress())
254 }
255
256 // Intermediate States
257 s.zki.ISOnChain[s.i] = big.NewInt(1)
258 }
259
260 switch tx.Type {
261 case common.TxTypeForceTransfer, common.TxTypeTransfer:
262 // go to the MT account of sender and receiver, and update balance
263 // & nonce
264 err := s.applyTransfer(tx.Tx(), 0) // 0 for the parameter toIdx, as at L1Tx ToIdx can only be 0 in the Deposit type case.
265 if err != nil {
266 log.Error(err)
267 return nil, nil, false, err
268 }
269 case common.TxTypeCreateAccountDeposit:
270 // add new account to the MT, update balance of the MT account
271 err := s.applyCreateAccount(tx)
272 if err != nil {
273 log.Error(err)
274 return nil, nil, false, err
275 }
276 // TODO applyCreateAccount will return the created account,
277 // which in the case type==TypeSynchronizer will be added to an
278 // array of created accounts that will be returned
279
280 if s.zki != nil {
281 s.zki.AuxFromIdx[s.i] = s.idx.BigInt() // last s.idx is the one used for creating the new account
282 s.zki.NewAccount[s.i] = big.NewInt(1)
283 }
284 case common.TxTypeDeposit:
285 // update balance of the MT account
286 err := s.applyDeposit(tx, false)
287 if err != nil {
288 log.Error(err)
289 return nil, nil, false, err
290 }
291 case common.TxTypeDepositTransfer:
292 // update balance in MT account, update balance & nonce of sender
293 // & receiver
294 err := s.applyDeposit(tx, true)
295 if err != nil {
296 log.Error(err)
297 return nil, nil, false, err
298 }
299 case common.TxTypeCreateAccountDepositTransfer:
300 // add new account to the merkletree, update balance in MT account,
301 // update balance & nonce of sender & receiver
302 err := s.applyCreateAccountDepositTransfer(tx)
303 if err != nil {
304 log.Error(err)
305 return nil, nil, false, err
306 }
307
308 if s.zki != nil {
309 s.zki.AuxFromIdx[s.i] = s.idx.BigInt() // last s.idx is the one used for creating the new account
310 s.zki.NewAccount[s.i] = big.NewInt(1)
311 }
312 case common.TxTypeExit:
313 // execute exit flow
314 exitAccount, newExit, err := s.applyExit(exitTree, tx.Tx())
315 if err != nil {
316 log.Error(err)
317 return nil, nil, false, err
318 }
319 return &tx.FromIdx, exitAccount, newExit, nil
320 default:
321 }
322
323 return nil, nil, false, nil
324}
325
326// processL2Tx process the given L2Tx applying the needed updates to the
327// StateDB depending on the transaction Type. It returns the 3 parameters
328// related to the Exit (in case of): Idx, ExitAccount, boolean determining if
329// the Exit created a new Leaf in the ExitTree.
330func (s *StateDB) processL2Tx(exitTree *merkletree.MerkleTree, tx *common.PoolL2Tx) (*common.Idx, *common.Account, bool, error) {
331 var err error
332 // if tx.ToIdx==0, get toIdx by ToEthAddr or ToBJJ
333 if tx.ToIdx == common.Idx(0) && tx.AuxToIdx == common.Idx(0) {
334 tx.AuxToIdx, err = s.GetIdxByEthAddrBJJ(tx.ToEthAddr, tx.ToBJJ)
335 if err != nil {
336 log.Error(err)
337 return nil, nil, false, err
338 }
339 }
340
341 // ZKInputs
342 if s.zki != nil {
343 // Txs
344 // s.zki.TxCompressedData[s.i] = tx.TxCompressedData() // uncomment once L1Tx.TxCompressedData is ready
345 // s.zki.TxCompressedDataV2[s.i] = tx.TxCompressedDataV2() // uncomment once L2Tx.TxCompressedDataV2 is ready
346 s.zki.FromIdx[s.i] = tx.FromIdx.BigInt()
347 s.zki.ToIdx[s.i] = tx.ToIdx.BigInt()
348
349 // fill AuxToIdx if needed
350 if tx.ToIdx == 0 {
351 // use toIdx that can have been filled by tx.ToIdx or
352 // if tx.Idx==0 (this case), toIdx is filled by the Idx
353 // from db by ToEthAddr&ToBJJ
354 s.zki.AuxToIdx[s.i] = tx.AuxToIdx.BigInt()
355 }
356
357 if tx.ToBJJ != nil {
358 s.zki.ToBJJAy[s.i] = tx.ToBJJ.Y
359 }
360 s.zki.ToEthAddr[s.i] = common.EthAddrToBigInt(tx.ToEthAddr)
361
362 s.zki.OnChain[s.i] = big.NewInt(0)
363 s.zki.NewAccount[s.i] = big.NewInt(0)
364
365 // L2Txs
366 // s.zki.RqOffset[s.i] = // TODO Rq once TxSelector is ready
367 // s.zki.RqTxCompressedDataV2[s.i] = // TODO
368 // s.zki.RqToEthAddr[s.i] = common.EthAddrToBigInt(tx.RqToEthAddr) // TODO
369 // s.zki.RqToBJJAy[s.i] = tx.ToBJJ.Y // TODO
370 s.zki.S[s.i] = tx.Signature.S
371 s.zki.R8x[s.i] = tx.Signature.R8.X
372 s.zki.R8y[s.i] = tx.Signature.R8.Y
373 }
374
375 // if StateDB type==TypeSynchronizer, will need to add Nonce
376 if s.typ == TypeSynchronizer {
377 // as type==TypeSynchronizer, always tx.ToIdx!=0
378 acc, err := s.GetAccount(tx.FromIdx)
379 if err != nil {
380 log.Error(err)
381 return nil, nil, false, err
382 }
383 tx.Nonce = acc.Nonce
384 tx.TokenID = acc.TokenID
385 }
386
387 switch tx.Type {
388 case common.TxTypeTransfer:
389 // go to the MT account of sender and receiver, and update
390 // balance & nonce
391 err = s.applyTransfer(tx.Tx(), tx.AuxToIdx)
392 if err != nil {
393 log.Error(err)
394 return nil, nil, false, err
395 }
396 case common.TxTypeExit:
397 // execute exit flow
398 exitAccount, newExit, err := s.applyExit(exitTree, tx.Tx())
399 if err != nil {
400 log.Error(err)
401 return nil, nil, false, err
402 }
403 return &tx.FromIdx, exitAccount, newExit, nil
404 default:
405 }
406 return nil, nil, false, nil
407}
408
409// applyCreateAccount creates a new account in the account of the depositer, it
410// stores the deposit value
411func (s *StateDB) applyCreateAccount(tx *common.L1Tx) error {
412 account := &common.Account{
413 TokenID: tx.TokenID,
414 Nonce: 0,
415 Balance: tx.LoadAmount,
416 PublicKey: tx.FromBJJ,
417 EthAddr: tx.FromEthAddr,
418 }
419
420 p, err := s.CreateAccount(common.Idx(s.idx+1), account)
421 if err != nil {
422 return err
423 }
424 if s.zki != nil {
425 s.zki.TokenID1[s.i] = tx.TokenID.BigInt()
426 s.zki.Nonce1[s.i] = big.NewInt(0)
427 if babyjub.PointCoordSign(tx.FromBJJ.X) {
428 s.zki.Sign1[s.i] = big.NewInt(1)
429 }
430 s.zki.Ay1[s.i] = tx.FromBJJ.Y
431 s.zki.Balance1[s.i] = tx.LoadAmount
432 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(tx.FromEthAddr)
433 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
434 if p.IsOld0 {
435 s.zki.IsOld0_1[s.i] = big.NewInt(1)
436 }
437 s.zki.OldKey1[s.i] = p.OldKey.BigInt()
438 s.zki.OldValue1[s.i] = p.OldValue.BigInt()
439 }
440
441 s.idx = s.idx + 1
442 return s.setIdx(s.idx)
443}
444
445// applyDeposit updates the balance in the account of the depositer, if
446// andTransfer parameter is set to true, the method will also apply the
447// Transfer of the L1Tx/DepositTransfer
448func (s *StateDB) applyDeposit(tx *common.L1Tx, transfer bool) error {
449 // deposit the tx.LoadAmount into the sender account
450 accSender, err := s.GetAccount(tx.FromIdx)
451 if err != nil {
452 return err
453 }
454 accSender.Balance = new(big.Int).Add(accSender.Balance, tx.LoadAmount)
455
456 // in case that the tx is a L1Tx>DepositTransfer
457 var accReceiver *common.Account
458 if transfer {
459 accReceiver, err = s.GetAccount(tx.ToIdx)
460 if err != nil {
461 return err
462 }
463 // subtract amount to the sender
464 accSender.Balance = new(big.Int).Sub(accSender.Balance, tx.Amount)
465 // add amount to the receiver
466 accReceiver.Balance = new(big.Int).Add(accReceiver.Balance, tx.Amount)
467 }
468 // update sender account in localStateDB
469 p, err := s.UpdateAccount(tx.FromIdx, accSender)
470 if err != nil {
471 return err
472 }
473 if s.zki != nil {
474 s.zki.TokenID1[s.i] = accSender.TokenID.BigInt()
475 s.zki.Nonce1[s.i] = accSender.Nonce.BigInt()
476 if babyjub.PointCoordSign(accSender.PublicKey.X) {
477 s.zki.Sign1[s.i] = big.NewInt(1)
478 }
479 s.zki.Ay1[s.i] = accSender.PublicKey.Y
480 s.zki.Balance1[s.i] = accSender.Balance
481 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(accSender.EthAddr)
482 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
483 // IsOld0_1, OldKey1, OldValue1 not needed as this is not an insert
484 }
485
486 // this is done after updating Sender Account (depositer)
487 if transfer {
488 // update receiver account in localStateDB
489 p, err := s.UpdateAccount(tx.ToIdx, accReceiver)
490 if err != nil {
491 return err
492 }
493 if s.zki != nil {
494 s.zki.TokenID2[s.i] = accReceiver.TokenID.BigInt()
495 s.zki.Nonce2[s.i] = accReceiver.Nonce.BigInt()
496 if babyjub.PointCoordSign(accReceiver.PublicKey.X) {
497 s.zki.Sign2[s.i] = big.NewInt(1)
498 }
499 s.zki.Ay2[s.i] = accReceiver.PublicKey.Y
500 s.zki.Balance2[s.i] = accReceiver.Balance
501 s.zki.EthAddr2[s.i] = common.EthAddrToBigInt(accReceiver.EthAddr)
502 s.zki.Siblings2[s.i] = siblingsToZKInputFormat(p.Siblings)
503 // IsOld0_2, OldKey2, OldValue2 not needed as this is not an insert
504 }
505 }
506
507 return nil
508}
509
510// applyTransfer updates the balance & nonce in the account of the sender, and
511// the balance in the account of the receiver.
512// Parameter 'toIdx' should be at 0 if the tx already has tx.ToIdx!=0, if
513// tx.ToIdx==0, then toIdx!=0, and will be used the toIdx parameter as Idx of
514// the receiver. This parameter is used when the tx.ToIdx is not specified and
515// the real ToIdx is found trhrough the ToEthAddr or ToBJJ.
516func (s *StateDB) applyTransfer(tx common.Tx, auxToIdx common.Idx) error {
517 if auxToIdx == common.Idx(0) {
518 auxToIdx = tx.ToIdx
519 }
520 // get sender and receiver accounts from localStateDB
521 accSender, err := s.GetAccount(tx.FromIdx)
522 if err != nil {
523 log.Error(err)
524 return err
525 }
526 accReceiver, err := s.GetAccount(auxToIdx)
527 if err != nil {
528 log.Error(err)
529 return err
530 }
531
532 // increment nonce
533 accSender.Nonce++
534
535 // subtract amount to the sender
536 accSender.Balance = new(big.Int).Sub(accSender.Balance, tx.Amount)
537 // add amount to the receiver
538 accReceiver.Balance = new(big.Int).Add(accReceiver.Balance, tx.Amount)
539
540 // update sender account in localStateDB
541 pSender, err := s.UpdateAccount(tx.FromIdx, accSender)
542 if err != nil {
543 log.Error(err)
544 return err
545 }
546 if s.zki != nil {
547 s.zki.TokenID1[s.i] = accSender.TokenID.BigInt()
548 s.zki.Nonce1[s.i] = accSender.Nonce.BigInt()
549 if babyjub.PointCoordSign(accSender.PublicKey.X) {
550 s.zki.Sign1[s.i] = big.NewInt(1)
551 }
552 s.zki.Ay1[s.i] = accSender.PublicKey.Y
553 s.zki.Balance1[s.i] = accSender.Balance
554 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(accSender.EthAddr)
555 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(pSender.Siblings)
556 }
557
558 // update receiver account in localStateDB
559 pReceiver, err := s.UpdateAccount(auxToIdx, accReceiver)
560 if err != nil {
561 return err
562 }
563 if s.zki != nil {
564 s.zki.TokenID2[s.i] = accReceiver.TokenID.BigInt()
565 s.zki.Nonce2[s.i] = accReceiver.Nonce.BigInt()
566 if babyjub.PointCoordSign(accReceiver.PublicKey.X) {
567 s.zki.Sign2[s.i] = big.NewInt(1)
568 }
569 s.zki.Ay2[s.i] = accReceiver.PublicKey.Y
570 s.zki.Balance2[s.i] = accReceiver.Balance
571 s.zki.EthAddr2[s.i] = common.EthAddrToBigInt(accReceiver.EthAddr)
572 s.zki.Siblings2[s.i] = siblingsToZKInputFormat(pReceiver.Siblings)
573 }
574
575 return nil
576}
577
578// applyCreateAccountDepositTransfer, in a single tx, creates a new account,
579// makes a deposit, and performs a transfer to another account
580func (s *StateDB) applyCreateAccountDepositTransfer(tx *common.L1Tx) error {
581 accSender := &common.Account{
582 TokenID: tx.TokenID,
583 Nonce: 0,
584 Balance: tx.LoadAmount,
585 PublicKey: tx.FromBJJ,
586 EthAddr: tx.FromEthAddr,
587 }
588 accSender.Balance = new(big.Int).Add(accSender.Balance, tx.LoadAmount)
589 accReceiver, err := s.GetAccount(tx.ToIdx)
590 if err != nil {
591 return err
592 }
593 // subtract amount to the sender
594 accSender.Balance = new(big.Int).Sub(accSender.Balance, tx.Amount)
595 // add amount to the receiver
596 accReceiver.Balance = new(big.Int).Add(accReceiver.Balance, tx.Amount)
597
598 // create Account of the Sender
599 p, err := s.CreateAccount(common.Idx(s.idx+1), accSender)
600 if err != nil {
601 return err
602 }
603 if s.zki != nil {
604 s.zki.TokenID1[s.i] = tx.TokenID.BigInt()
605 s.zki.Nonce1[s.i] = big.NewInt(0)
606 if babyjub.PointCoordSign(tx.FromBJJ.X) {
607 s.zki.Sign1[s.i] = big.NewInt(1)
608 }
609 s.zki.Ay1[s.i] = tx.FromBJJ.Y
610 s.zki.Balance1[s.i] = tx.LoadAmount
611 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(tx.FromEthAddr)
612 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
613 if p.IsOld0 {
614 s.zki.IsOld0_1[s.i] = big.NewInt(1)
615 }
616 s.zki.OldKey1[s.i] = p.OldKey.BigInt()
617 s.zki.OldValue1[s.i] = p.OldValue.BigInt()
618 }
619
620 // update receiver account in localStateDB
621 p, err = s.UpdateAccount(tx.ToIdx, accReceiver)
622 if err != nil {
623 return err
624 }
625 if s.zki != nil {
626 s.zki.TokenID2[s.i] = accReceiver.TokenID.BigInt()
627 s.zki.Nonce2[s.i] = accReceiver.Nonce.BigInt()
628 if babyjub.PointCoordSign(accReceiver.PublicKey.X) {
629 s.zki.Sign2[s.i] = big.NewInt(1)
630 }
631 s.zki.Ay2[s.i] = accReceiver.PublicKey.Y
632 s.zki.Balance2[s.i] = accReceiver.Balance
633 s.zki.EthAddr2[s.i] = common.EthAddrToBigInt(accReceiver.EthAddr)
634 s.zki.Siblings2[s.i] = siblingsToZKInputFormat(p.Siblings)
635 }
636
637 s.idx = s.idx + 1
638 return s.setIdx(s.idx)
639}
640
641// It returns the ExitAccount and a boolean determining if the Exit created a
642// new Leaf in the ExitTree.
643func (s *StateDB) applyExit(exitTree *merkletree.MerkleTree, tx common.Tx) (*common.Account, bool, error) {
644 // 0. subtract tx.Amount from current Account in StateMT
645 // add the tx.Amount into the Account (tx.FromIdx) in the ExitMT
646 acc, err := s.GetAccount(tx.FromIdx)
647 if err != nil {
648 return nil, false, err
649 }
650 acc.Balance = new(big.Int).Sub(acc.Balance, tx.Amount)
651 p, err := s.UpdateAccount(tx.FromIdx, acc)
652 if err != nil {
653 return nil, false, err
654 }
655 if s.zki != nil {
656 s.zki.TokenID1[s.i] = acc.TokenID.BigInt()
657 s.zki.Nonce1[s.i] = acc.Nonce.BigInt()
658 if babyjub.PointCoordSign(acc.PublicKey.X) {
659 s.zki.Sign1[s.i] = big.NewInt(1)
660 }
661 s.zki.Ay1[s.i] = acc.PublicKey.Y
662 s.zki.Balance1[s.i] = acc.Balance
663 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(acc.EthAddr)
664 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
665 }
666
667 if exitTree == nil {
668 return nil, false, nil
669 }
670 exitAccount, err := getAccountInTreeDB(exitTree.DB(), tx.FromIdx)
671 if err == db.ErrNotFound {
672 // 1a. if idx does not exist in exitTree:
673 // add new leaf 'ExitTreeLeaf', where ExitTreeLeaf.Balance = exitAmount (exitAmount=tx.Amount)
674 exitAccount := &common.Account{
675 TokenID: acc.TokenID,
676 Nonce: common.Nonce(1),
677 Balance: tx.Amount,
678 PublicKey: acc.PublicKey,
679 EthAddr: acc.EthAddr,
680 }
681 _, err = createAccountInTreeDB(exitTree.DB(), exitTree, tx.FromIdx, exitAccount)
682 return exitAccount, true, err
683 } else if err != nil {
684 return exitAccount, false, err
685 }
686
687 // 1b. if idx already exist in exitTree:
688 // update account, where account.Balance += exitAmount
689 exitAccount.Balance = new(big.Int).Add(exitAccount.Balance, tx.Amount)
690 _, err = updateAccountInTreeDB(exitTree.DB(), exitTree, tx.FromIdx, exitAccount)
691 return exitAccount, false, err
692}
693
694// getIdx returns the stored Idx from the localStateDB, which is the last Idx
695// used for an Account in the localStateDB.
696func (s *StateDB) getIdx() (common.Idx, error) {
697 idxBytes, err := s.DB().Get(keyidx)
698 if err == db.ErrNotFound {
699 return 0, nil
700 }
701 if err != nil {
702 return 0, err
703 }
704 return common.IdxFromBytes(idxBytes[:4])
705}
706
707// setIdx stores Idx in the localStateDB
708func (s *StateDB) setIdx(idx common.Idx) error {
709 tx, err := s.DB().NewTx()
710 if err != nil {
711 return err
712 }
713 idxBytes, err := idx.Bytes()
714 if err != nil {
715 return err
716 }
717 err = tx.Put(keyidx, idxBytes[:])
718 if err != nil {
719 return err
720 }
721 if err := tx.Commit(); err != nil {
722 return err
723 }
724 return nil
725}