hermez-node/db/statedb/txprocessors.go
db/statedb/txprocessors.goRaw
1package statedb
2
3import (
4 "errors"
5 "math/big"
6
7 "github.com/hermeznetwork/hermez-node/common"
8 "github.com/hermeznetwork/hermez-node/log"
9 "github.com/iden3/go-iden3-crypto/babyjub"
10 "github.com/iden3/go-merkletree"
11 "github.com/iden3/go-merkletree/db"
12 "github.com/iden3/go-merkletree/db/memory"
13)
14
15var (
16 // keyidx is used as key in the db to store the current Idx
17 keyidx = []byte("idx")
18)
19
20func (s *StateDB) resetZKInputs() {
21 s.zki = nil
22 s.i = 0
23}
24
25type processedExit struct {
26 exit bool
27 newExit bool
28 idx common.Idx
29 acc common.Account
30}
31
32// ProcessTxs process the given L1Txs & L2Txs applying the needed updates to
33// the StateDB depending on the transaction Type. If StateDB
34// type==TypeBatchBuilder, returns the common.ZKInputs to generate the
35// SnarkProof later used by the BatchBuilder. If StateDB
36// type==TypeSynchronizer, assumes that the call is done from the Synchronizer,
37// returns common.ExitTreeLeaf that is later used by the Synchronizer to update
38// the HistoryDB, and adds Nonce & TokenID to the L2Txs.
39func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs []*common.PoolL2Tx) (*common.ZKInputs, []common.ExitInfo, error) {
40 var err error
41 var exitTree *merkletree.MerkleTree
42
43 if s.zki != nil {
44 return nil, nil, errors.New("Expected StateDB.zki==nil, something went wrong and it's not empty")
45 }
46 defer s.resetZKInputs()
47
48 nTx := len(l1usertxs) + len(l1coordinatortxs) + len(l2txs)
49 if nTx == 0 {
50 // TODO return ZKInputs of batch without txs
51 return nil, nil, nil
52 }
53 exits := make([]processedExit, nTx)
54
55 if s.typ == TypeBatchBuilder {
56 s.zki = common.NewZKInputs(nTx, 24, 32) // TODO this values will be parameters of the function, taken from config file/coordinator call
57 s.zki.OldLastIdx = (s.idx - 1).BigInt()
58 s.zki.OldStateRoot = s.mt.Root().BigInt()
59 }
60
61 // TBD if ExitTree is only in memory or stored in disk, for the moment
62 // only needed in memory
63 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
64 exitTree, err = merkletree.NewMerkleTree(memory.NewMemoryStorage(), s.mt.MaxLevels())
65 if err != nil {
66 return nil, nil, err
67 }
68 }
69
70 // assumption: l1usertx are sorted by L1Tx.Position
71 for _, tx := range l1usertxs {
72 exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, tx)
73 if err != nil {
74 return nil, nil, err
75 }
76 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
77 if exitIdx != nil && exitTree != nil {
78 exits[s.i] = processedExit{
79 exit: true,
80 newExit: newExit,
81 idx: *exitIdx,
82 acc: *exitAccount,
83 }
84 }
85 s.i++
86 }
87 }
88 for _, tx := range l1coordinatortxs {
89 exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, tx)
90 if err != nil {
91 return nil, nil, err
92 }
93 if exitIdx != nil {
94 log.Error("Unexpected Exit in L1CoordinatorTx")
95 }
96 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
97 if exitIdx != nil && exitTree != nil {
98 exits[s.i] = processedExit{
99 exit: true,
100 newExit: newExit,
101 idx: *exitIdx,
102 acc: *exitAccount,
103 }
104 }
105 s.i++
106 }
107 }
108 for _, tx := range l2txs {
109 exitIdx, exitAccount, newExit, err := s.processL2Tx(exitTree, tx)
110 if err != nil {
111 return nil, nil, err
112 }
113 if s.typ == TypeSynchronizer || s.typ == TypeBatchBuilder {
114 if exitIdx != nil && exitTree != nil {
115 exits[s.i] = processedExit{
116 exit: true,
117 newExit: newExit,
118 idx: *exitIdx,
119 acc: *exitAccount,
120 }
121 }
122 s.i++
123 }
124 }
125
126 if s.typ == TypeTxSelector {
127 return nil, nil, nil
128 }
129
130 // once all txs processed (exitTree root frozen), for each Exit,
131 // generate common.ExitInfo data
132 var exitInfos []common.ExitInfo
133 for i := 0; i < nTx; i++ {
134 if !exits[i].exit {
135 continue
136 }
137 exitIdx := exits[i].idx
138 exitAccount := exits[i].acc
139
140 // 0. generate MerkleProof
141 p, err := exitTree.GenerateCircomVerifierProof(exitIdx.BigInt(), nil)
142 if err != nil {
143 return nil, nil, err
144 }
145 // 1. generate common.ExitInfo
146 ei := common.ExitInfo{
147 AccountIdx: exitIdx,
148 MerkleProof: p,
149 Balance: exitAccount.Balance,
150 }
151 exitInfos = append(exitInfos, ei)
152
153 if s.zki != nil {
154 s.zki.TokenID2[i] = exitAccount.TokenID.BigInt()
155 s.zki.Nonce2[i] = exitAccount.Nonce.BigInt()
156 if babyjub.PointCoordSign(exitAccount.PublicKey.X) {
157 s.zki.Sign2[i] = big.NewInt(1)
158 }
159 s.zki.Ay2[i] = exitAccount.PublicKey.Y
160 s.zki.Balance2[i] = exitAccount.Balance
161 s.zki.EthAddr2[i] = common.EthAddrToBigInt(exitAccount.EthAddr)
162 s.zki.Siblings2[i] = p.Siblings
163 if exits[i].newExit {
164 s.zki.NewExit[i] = big.NewInt(1)
165 }
166 if p.IsOld0 {
167 s.zki.IsOld0_2[i] = big.NewInt(1)
168 }
169 s.zki.OldKey2[i] = p.OldKey.BigInt()
170 s.zki.OldValue2[i] = p.OldValue.BigInt()
171 }
172 }
173 if s.typ == TypeSynchronizer {
174 return nil, exitInfos, nil
175 }
176
177 // compute last ZKInputs parameters
178 s.zki.GlobalChainID = big.NewInt(0) // TODO, 0: ethereum, this will be get from config file
179 // zki.FeeIdxs = ? // TODO, this will be get from the config file
180 tokenIDs, err := s.getTokenIDsBigInt(l1usertxs, l1coordinatortxs, l2txs)
181 if err != nil {
182 return nil, nil, err
183 }
184 s.zki.FeePlanTokens = tokenIDs
185
186 // s.zki.ISInitStateRootFee = s.mt.Root().BigInt()
187
188 // TODO once the Node Config sets the Accounts where to send the Fees
189 // compute fees & update ZKInputs
190
191 // return exitInfos, so Synchronizer will be able to store it into
192 // HistoryDB for the concrete BatchNum
193 return s.zki, exitInfos, nil
194}
195
196// getTokenIDsBigInt returns the list of TokenIDs in *big.Int format
197func (s *StateDB) getTokenIDsBigInt(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs []*common.PoolL2Tx) ([]*big.Int, error) {
198 tokenIDs := make(map[common.TokenID]bool)
199 for i := 0; i < len(l1usertxs); i++ {
200 tokenIDs[l1usertxs[i].TokenID] = true
201 }
202 for i := 0; i < len(l1coordinatortxs); i++ {
203 tokenIDs[l1coordinatortxs[i].TokenID] = true
204 }
205 for i := 0; i < len(l2txs); i++ {
206 // as L2Tx does not have parameter TokenID, get it from the
207 // AccountsDB (in the StateDB)
208 acc, err := s.GetAccount(l2txs[i].ToIdx)
209 if err != nil {
210 return nil, err
211 }
212 tokenIDs[acc.TokenID] = true
213 }
214 var tBI []*big.Int
215 for t := range tokenIDs {
216 tBI = append(tBI, t.BigInt())
217 }
218 return tBI, nil
219}
220
221// processL1Tx process the given L1Tx applying the needed updates to the
222// StateDB depending on the transaction Type. It returns the 3 parameters
223// related to the Exit (in case of): Idx, ExitAccount, boolean determining if
224// the Exit created a new Leaf in the ExitTree.
225func (s *StateDB) processL1Tx(exitTree *merkletree.MerkleTree, tx *common.L1Tx) (*common.Idx, *common.Account, bool, error) {
226 // ZKInputs
227 if s.zki != nil {
228 // Txs
229 // s.zki.TxCompressedData[s.i] = tx.TxCompressedData() // uncomment once L1Tx.TxCompressedData is ready
230 s.zki.FromIdx[s.i] = tx.FromIdx.BigInt()
231 s.zki.ToIdx[s.i] = tx.ToIdx.BigInt()
232 s.zki.OnChain[s.i] = big.NewInt(1)
233
234 // L1Txs
235 s.zki.LoadAmountF[s.i] = tx.LoadAmount
236 s.zki.FromEthAddr[s.i] = common.EthAddrToBigInt(tx.FromEthAddr)
237 if tx.FromBJJ != nil {
238 s.zki.FromBJJCompressed[s.i] = BJJCompressedTo256BigInts(tx.FromBJJ.Compress())
239 }
240
241 // Intermediate States
242 s.zki.ISOnChain[s.i] = big.NewInt(1)
243 }
244
245 switch tx.Type {
246 case common.TxTypeForceTransfer, common.TxTypeTransfer:
247 // go to the MT account of sender and receiver, and update balance
248 // & nonce
249 err := s.applyTransfer(tx.Tx(), 0) // 0 for the parameter toIdx, as at L1Tx ToIdx can only be 0 in the Deposit type case.
250 if err != nil {
251 return nil, nil, false, err
252 }
253 case common.TxTypeCreateAccountDeposit:
254 // add new account to the MT, update balance of the MT account
255 err := s.applyCreateAccount(tx)
256 if err != nil {
257 return nil, nil, false, err
258 }
259
260 if s.zki != nil {
261 s.zki.AuxFromIdx[s.i] = s.idx.BigInt() // last s.idx is the one used for creating the new account
262 s.zki.NewAccount[s.i] = big.NewInt(1)
263 }
264 case common.TxTypeDeposit:
265 // update balance of the MT account
266 err := s.applyDeposit(tx, false)
267 if err != nil {
268 return nil, nil, false, err
269 }
270 case common.TxTypeDepositTransfer:
271 // update balance in MT account, update balance & nonce of sender
272 // & receiver
273 err := s.applyDeposit(tx, true)
274 if err != nil {
275 return nil, nil, false, err
276 }
277 case common.TxTypeCreateAccountDepositTransfer:
278 // add new account to the merkletree, update balance in MT account,
279 // update balance & nonce of sender & receiver
280 err := s.applyCreateAccountDepositTransfer(tx)
281 if err != nil {
282 return nil, nil, false, err
283 }
284
285 if s.zki != nil {
286 s.zki.AuxFromIdx[s.i] = s.idx.BigInt() // last s.idx is the one used for creating the new account
287 s.zki.NewAccount[s.i] = big.NewInt(1)
288 }
289 case common.TxTypeExit:
290 // execute exit flow
291 exitAccount, newExit, err := s.applyExit(exitTree, tx.Tx())
292 if err != nil {
293 return nil, nil, false, err
294 }
295 return &tx.FromIdx, exitAccount, newExit, nil
296 default:
297 }
298
299 return nil, nil, false, nil
300}
301
302// processL2Tx process the given L2Tx applying the needed updates to the
303// StateDB depending on the transaction Type. It returns the 3 parameters
304// related to the Exit (in case of): Idx, ExitAccount, boolean determining if
305// the Exit created a new Leaf in the ExitTree.
306func (s *StateDB) processL2Tx(exitTree *merkletree.MerkleTree, tx *common.PoolL2Tx) (*common.Idx, *common.Account, bool, error) {
307 var err error
308 var auxToIdx common.Idx
309 // if tx.ToIdx==0, get toIdx by ToEthAddr or ToBJJ
310 if tx.ToIdx == common.Idx(0) {
311 auxToIdx, err = s.GetIdxByEthAddrBJJ(tx.ToEthAddr, tx.ToBJJ)
312 if err != nil {
313 log.Error(err)
314 return nil, nil, false, err
315 }
316 }
317
318 // ZKInputs
319 if s.zki != nil {
320 // Txs
321 // s.zki.TxCompressedData[s.i] = tx.TxCompressedData() // uncomment once L1Tx.TxCompressedData is ready
322 // s.zki.TxCompressedDataV2[s.i] = tx.TxCompressedDataV2() // uncomment once L2Tx.TxCompressedDataV2 is ready
323 s.zki.FromIdx[s.i] = tx.FromIdx.BigInt()
324 s.zki.ToIdx[s.i] = tx.ToIdx.BigInt()
325
326 // fill AuxToIdx if needed
327 if tx.ToIdx == common.Idx(0) {
328 // use toIdx that can have been filled by tx.ToIdx or
329 // if tx.Idx==0 (this case), toIdx is filled by the Idx
330 // from db by ToEthAddr&ToBJJ
331 s.zki.AuxToIdx[s.i] = auxToIdx.BigInt()
332 }
333
334 s.zki.ToBJJAy[s.i] = tx.ToBJJ.Y
335 s.zki.ToEthAddr[s.i] = common.EthAddrToBigInt(tx.ToEthAddr)
336
337 s.zki.OnChain[s.i] = big.NewInt(0)
338 s.zki.NewAccount[s.i] = big.NewInt(0)
339
340 // L2Txs
341 // s.zki.RqOffset[s.i] = // TODO Rq once TxSelector is ready
342 // s.zki.RqTxCompressedDataV2[s.i] = // TODO
343 // s.zki.RqToEthAddr[s.i] = common.EthAddrToBigInt(tx.RqToEthAddr) // TODO
344 // s.zki.RqToBJJAy[s.i] = tx.ToBJJ.Y // TODO
345 s.zki.S[s.i] = tx.Signature.S
346 s.zki.R8x[s.i] = tx.Signature.R8.X
347 s.zki.R8y[s.i] = tx.Signature.R8.Y
348 }
349
350 // if StateDB type==TypeSynchronizer, will need to add Nonce and
351 // TokenID to the transaction
352 if s.typ == TypeSynchronizer {
353 acc, err := s.GetAccount(tx.ToIdx)
354 if err != nil {
355 return nil, nil, false, err
356 }
357 tx.Nonce = acc.Nonce
358 tx.TokenID = acc.TokenID
359 }
360
361 switch tx.Type {
362 case common.TxTypeTransfer:
363 // go to the MT account of sender and receiver, and update
364 // balance & nonce
365 err = s.applyTransfer(tx.Tx(), auxToIdx)
366 if err != nil {
367 return nil, nil, false, err
368 }
369 case common.TxTypeExit:
370 // execute exit flow
371 exitAccount, newExit, err := s.applyExit(exitTree, tx.Tx())
372 if err != nil {
373 return nil, nil, false, err
374 }
375 return &tx.FromIdx, exitAccount, newExit, nil
376 default:
377 }
378 return nil, nil, false, nil
379}
380
381// applyCreateAccount creates a new account in the account of the depositer, it
382// stores the deposit value
383func (s *StateDB) applyCreateAccount(tx *common.L1Tx) error {
384 account := &common.Account{
385 TokenID: tx.TokenID,
386 Nonce: 0,
387 Balance: tx.LoadAmount,
388 PublicKey: tx.FromBJJ,
389 EthAddr: tx.FromEthAddr,
390 }
391
392 p, err := s.CreateAccount(common.Idx(s.idx+1), account)
393 if err != nil {
394 return err
395 }
396 if s.zki != nil {
397 s.zki.TokenID1[s.i] = tx.TokenID.BigInt()
398 s.zki.Nonce1[s.i] = big.NewInt(0)
399 if babyjub.PointCoordSign(tx.FromBJJ.X) {
400 s.zki.Sign1[s.i] = big.NewInt(1)
401 }
402 s.zki.Ay1[s.i] = tx.FromBJJ.Y
403 s.zki.Balance1[s.i] = tx.LoadAmount
404 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(tx.FromEthAddr)
405 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
406 if p.IsOld0 {
407 s.zki.IsOld0_1[s.i] = big.NewInt(1)
408 }
409 s.zki.OldKey1[s.i] = p.OldKey.BigInt()
410 s.zki.OldValue1[s.i] = p.OldValue.BigInt()
411 }
412
413 s.idx = s.idx + 1
414 return s.setIdx(s.idx)
415}
416
417// applyDeposit updates the balance in the account of the depositer, if
418// andTransfer parameter is set to true, the method will also apply the
419// Transfer of the L1Tx/DepositTransfer
420func (s *StateDB) applyDeposit(tx *common.L1Tx, transfer bool) error {
421 // deposit the tx.LoadAmount into the sender account
422 accSender, err := s.GetAccount(tx.FromIdx)
423 if err != nil {
424 return err
425 }
426 accSender.Balance = new(big.Int).Add(accSender.Balance, tx.LoadAmount)
427
428 // in case that the tx is a L1Tx>DepositTransfer
429 var accReceiver *common.Account
430 if transfer {
431 accReceiver, err = s.GetAccount(tx.ToIdx)
432 if err != nil {
433 return err
434 }
435 // subtract amount to the sender
436 accSender.Balance = new(big.Int).Sub(accSender.Balance, tx.Amount)
437 // add amount to the receiver
438 accReceiver.Balance = new(big.Int).Add(accReceiver.Balance, tx.Amount)
439 }
440 // update sender account in localStateDB
441 p, err := s.UpdateAccount(tx.FromIdx, accSender)
442 if err != nil {
443 return err
444 }
445 if s.zki != nil {
446 s.zki.TokenID1[s.i] = accSender.TokenID.BigInt()
447 s.zki.Nonce1[s.i] = accSender.Nonce.BigInt()
448 if babyjub.PointCoordSign(accSender.PublicKey.X) {
449 s.zki.Sign1[s.i] = big.NewInt(1)
450 }
451 s.zki.Ay1[s.i] = accSender.PublicKey.Y
452 s.zki.Balance1[s.i] = accSender.Balance
453 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(accSender.EthAddr)
454 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
455 // IsOld0_1, OldKey1, OldValue1 not needed as this is not an insert
456 }
457
458 // this is done after updating Sender Account (depositer)
459 if transfer {
460 // update receiver account in localStateDB
461 p, err := s.UpdateAccount(tx.ToIdx, accReceiver)
462 if err != nil {
463 return err
464 }
465 if s.zki != nil {
466 s.zki.TokenID2[s.i] = accReceiver.TokenID.BigInt()
467 s.zki.Nonce2[s.i] = accReceiver.Nonce.BigInt()
468 if babyjub.PointCoordSign(accReceiver.PublicKey.X) {
469 s.zki.Sign2[s.i] = big.NewInt(1)
470 }
471 s.zki.Ay2[s.i] = accReceiver.PublicKey.Y
472 s.zki.Balance2[s.i] = accReceiver.Balance
473 s.zki.EthAddr2[s.i] = common.EthAddrToBigInt(accReceiver.EthAddr)
474 s.zki.Siblings2[s.i] = siblingsToZKInputFormat(p.Siblings)
475 // IsOld0_2, OldKey2, OldValue2 not needed as this is not an insert
476 }
477 }
478
479 return nil
480}
481
482// applyTransfer updates the balance & nonce in the account of the sender, and
483// the balance in the account of the receiver.
484// Parameter 'toIdx' should be at 0 if the tx already has tx.ToIdx!=0, if
485// tx.ToIdx==0, then toIdx!=0, and will be used the toIdx parameter as Idx of
486// the receiver. This parameter is used when the tx.ToIdx is not specified and
487// the real ToIdx is found trhrough the ToEthAddr or ToBJJ.
488func (s *StateDB) applyTransfer(tx *common.Tx, auxToIdx common.Idx) error {
489 if auxToIdx == 0 {
490 auxToIdx = tx.ToIdx
491 }
492 // get sender and receiver accounts from localStateDB
493 accSender, err := s.GetAccount(tx.FromIdx)
494 if err != nil {
495 return err
496 }
497 accReceiver, err := s.GetAccount(auxToIdx)
498 if err != nil {
499 return err
500 }
501
502 // increment nonce
503 accSender.Nonce++
504
505 // subtract amount to the sender
506 accSender.Balance = new(big.Int).Sub(accSender.Balance, tx.Amount)
507 // add amount to the receiver
508 accReceiver.Balance = new(big.Int).Add(accReceiver.Balance, tx.Amount)
509
510 // update sender account in localStateDB
511 pSender, err := s.UpdateAccount(tx.FromIdx, accSender)
512 if err != nil {
513 return err
514 }
515 if s.zki != nil {
516 s.zki.TokenID1[s.i] = accSender.TokenID.BigInt()
517 s.zki.Nonce1[s.i] = accSender.Nonce.BigInt()
518 if babyjub.PointCoordSign(accSender.PublicKey.X) {
519 s.zki.Sign1[s.i] = big.NewInt(1)
520 }
521 s.zki.Ay1[s.i] = accSender.PublicKey.Y
522 s.zki.Balance1[s.i] = accSender.Balance
523 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(accSender.EthAddr)
524 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(pSender.Siblings)
525 }
526
527 // update receiver account in localStateDB
528 pReceiver, err := s.UpdateAccount(auxToIdx, accReceiver)
529 if err != nil {
530 return err
531 }
532 if s.zki != nil {
533 s.zki.TokenID2[s.i] = accReceiver.TokenID.BigInt()
534 s.zki.Nonce2[s.i] = accReceiver.Nonce.BigInt()
535 if babyjub.PointCoordSign(accReceiver.PublicKey.X) {
536 s.zki.Sign2[s.i] = big.NewInt(1)
537 }
538 s.zki.Ay2[s.i] = accReceiver.PublicKey.Y
539 s.zki.Balance2[s.i] = accReceiver.Balance
540 s.zki.EthAddr2[s.i] = common.EthAddrToBigInt(accReceiver.EthAddr)
541 s.zki.Siblings2[s.i] = siblingsToZKInputFormat(pReceiver.Siblings)
542 }
543
544 return nil
545}
546
547// applyCreateAccountDepositTransfer, in a single tx, creates a new account,
548// makes a deposit, and performs a transfer to another account
549func (s *StateDB) applyCreateAccountDepositTransfer(tx *common.L1Tx) error {
550 accSender := &common.Account{
551 TokenID: tx.TokenID,
552 Nonce: 0,
553 Balance: tx.LoadAmount,
554 PublicKey: tx.FromBJJ,
555 EthAddr: tx.FromEthAddr,
556 }
557 accSender.Balance = new(big.Int).Add(accSender.Balance, tx.LoadAmount)
558 accReceiver, err := s.GetAccount(tx.ToIdx)
559 if err != nil {
560 return err
561 }
562 // subtract amount to the sender
563 accSender.Balance = new(big.Int).Sub(accSender.Balance, tx.Amount)
564 // add amount to the receiver
565 accReceiver.Balance = new(big.Int).Add(accReceiver.Balance, tx.Amount)
566
567 // create Account of the Sender
568 p, err := s.CreateAccount(common.Idx(s.idx+1), accSender)
569 if err != nil {
570 return err
571 }
572 if s.zki != nil {
573 s.zki.TokenID1[s.i] = tx.TokenID.BigInt()
574 s.zki.Nonce1[s.i] = big.NewInt(0)
575 if babyjub.PointCoordSign(tx.FromBJJ.X) {
576 s.zki.Sign1[s.i] = big.NewInt(1)
577 }
578 s.zki.Ay1[s.i] = tx.FromBJJ.Y
579 s.zki.Balance1[s.i] = tx.LoadAmount
580 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(tx.FromEthAddr)
581 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
582 if p.IsOld0 {
583 s.zki.IsOld0_1[s.i] = big.NewInt(1)
584 }
585 s.zki.OldKey1[s.i] = p.OldKey.BigInt()
586 s.zki.OldValue1[s.i] = p.OldValue.BigInt()
587 }
588
589 // update receiver account in localStateDB
590 p, err = s.UpdateAccount(tx.ToIdx, accReceiver)
591 if err != nil {
592 return err
593 }
594 if s.zki != nil {
595 s.zki.TokenID2[s.i] = accReceiver.TokenID.BigInt()
596 s.zki.Nonce2[s.i] = accReceiver.Nonce.BigInt()
597 if babyjub.PointCoordSign(accReceiver.PublicKey.X) {
598 s.zki.Sign2[s.i] = big.NewInt(1)
599 }
600 s.zki.Ay2[s.i] = accReceiver.PublicKey.Y
601 s.zki.Balance2[s.i] = accReceiver.Balance
602 s.zki.EthAddr2[s.i] = common.EthAddrToBigInt(accReceiver.EthAddr)
603 s.zki.Siblings2[s.i] = siblingsToZKInputFormat(p.Siblings)
604 }
605
606 s.idx = s.idx + 1
607 return s.setIdx(s.idx)
608}
609
610// It returns the ExitAccount and a boolean determining if the Exit created a
611// new Leaf in the ExitTree.
612func (s *StateDB) applyExit(exitTree *merkletree.MerkleTree, tx *common.Tx) (*common.Account, bool, error) {
613 // 0. subtract tx.Amount from current Account in StateMT
614 // add the tx.Amount into the Account (tx.FromIdx) in the ExitMT
615 acc, err := s.GetAccount(tx.FromIdx)
616 if err != nil {
617 return nil, false, err
618 }
619 acc.Balance = new(big.Int).Sub(acc.Balance, tx.Amount)
620 p, err := s.UpdateAccount(tx.FromIdx, acc)
621 if err != nil {
622 return nil, false, err
623 }
624 if s.zki != nil {
625 s.zki.TokenID1[s.i] = acc.TokenID.BigInt()
626 s.zki.Nonce1[s.i] = acc.Nonce.BigInt()
627 if babyjub.PointCoordSign(acc.PublicKey.X) {
628 s.zki.Sign1[s.i] = big.NewInt(1)
629 }
630 s.zki.Ay1[s.i] = acc.PublicKey.Y
631 s.zki.Balance1[s.i] = acc.Balance
632 s.zki.EthAddr1[s.i] = common.EthAddrToBigInt(acc.EthAddr)
633 s.zki.Siblings1[s.i] = siblingsToZKInputFormat(p.Siblings)
634 }
635
636 if exitTree == nil {
637 return nil, false, nil
638 }
639 exitAccount, err := getAccountInTreeDB(exitTree.DB(), tx.FromIdx)
640 if err == db.ErrNotFound {
641 // 1a. if idx does not exist in exitTree:
642 // add new leaf 'ExitTreeLeaf', where ExitTreeLeaf.Balance = exitAmount (exitAmount=tx.Amount)
643 exitAccount := &common.Account{
644 TokenID: acc.TokenID,
645 Nonce: common.Nonce(1),
646 Balance: tx.Amount,
647 PublicKey: acc.PublicKey,
648 EthAddr: acc.EthAddr,
649 }
650 _, err = createAccountInTreeDB(exitTree.DB(), exitTree, tx.FromIdx, exitAccount)
651 return exitAccount, true, err
652 } else if err != nil {
653 return exitAccount, false, err
654 }
655
656 // 1b. if idx already exist in exitTree:
657 // update account, where account.Balance += exitAmount
658 exitAccount.Balance = new(big.Int).Add(exitAccount.Balance, tx.Amount)
659 _, err = updateAccountInTreeDB(exitTree.DB(), exitTree, tx.FromIdx, exitAccount)
660 return exitAccount, false, err
661}
662
663// getIdx returns the stored Idx from the localStateDB, which is the last Idx
664// used for an Account in the localStateDB.
665func (s *StateDB) getIdx() (common.Idx, error) {
666 idxBytes, err := s.DB().Get(keyidx)
667 if err == db.ErrNotFound {
668 return 0, nil
669 }
670 if err != nil {
671 return 0, err
672 }
673 return common.IdxFromBytes(idxBytes[:4])
674}
675
676// setIdx stores Idx in the localStateDB
677func (s *StateDB) setIdx(idx common.Idx) error {
678 tx, err := s.DB().NewTx()
679 if err != nil {
680 return err
681 }
682 idxBytes, err := idx.Bytes()
683 if err != nil {
684 return err
685 }
686 err = tx.Put(keyidx, idxBytes[:])
687 if err != nil {
688 return err
689 }
690 if err := tx.Commit(); err != nil {
691 return err
692 }
693 return nil
694}