-
Notifications
You must be signed in to change notification settings - Fork 5
/
utils.ts
441 lines (397 loc) · 20.7 KB
/
utils.ts
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
import assert from 'assert'
import { BigNumber, ethers } from 'ethers'
import Unirep from "../artifacts/contracts/Unirep.sol/Unirep.json"
import { numAttestationsPerEpochKey } from '../config/testLocal'
import { Attestation, IEpochTreeLeaf, UnirepState } from './UnirepState'
import { IUserStateLeaf, UserState } from './UserState'
import { hashLeftRight } from 'maci-crypto'
import { computeEmptyUserStateRoot } from '../test/utils'
/*
* Retrieves and parses on-chain Unirep contract data to create an off-chain
* representation as a UnirepState object.
* @param provider An Ethereum provider
* @param address The address of the Unirep contract
* @param startBlock The block number when Unirep contract is deployed
*/
const genUnirepStateFromContract = async (
provider: ethers.providers.Provider,
address: string,
startBlock: number,
) => {
const unirepContract = new ethers.Contract(
address,
Unirep.abi,
provider,
)
const treeDepths_ = await unirepContract.treeDepths()
const globalStateTreeDepth = treeDepths_.globalStateTreeDepth
const userStateTreeDepth = treeDepths_.userStateTreeDepth
const epochTreeDepth = treeDepths_.epochTreeDepth
const nullifierTreeDepth = treeDepths_.nullifierTreeDepth
const attestingFee = await unirepContract.attestingFee()
const epochLength = await unirepContract.epochLength()
const numEpochKeyNoncePerEpoch = await unirepContract.numEpochKeyNoncePerEpoch()
const unirepState = new UnirepState(
ethers.BigNumber.from(globalStateTreeDepth).toNumber(),
ethers.BigNumber.from(userStateTreeDepth).toNumber(),
ethers.BigNumber.from(epochTreeDepth).toNumber(),
ethers.BigNumber.from(nullifierTreeDepth).toNumber(),
attestingFee,
ethers.BigNumber.from(epochLength).toNumber(),
ethers.BigNumber.from(numEpochKeyNoncePerEpoch).toNumber(),
numAttestationsPerEpochKey,
)
const newGSTLeafInsertedFilter = unirepContract.filters.NewGSTLeafInserted()
const newGSTLeafInsertedEvents = await unirepContract.queryFilter(newGSTLeafInsertedFilter, startBlock)
const attestationSubmittedFilter = unirepContract.filters.AttestationSubmitted()
const attestationSubmittedEvents = await unirepContract.queryFilter(attestationSubmittedFilter, startBlock)
const epochEndedFilter = unirepContract.filters.EpochEnded()
const epochEndedEvents = await unirepContract.queryFilter(epochEndedFilter, startBlock)
const userStateTransitionedFilter = unirepContract.filters.UserStateTransitioned()
const userStateTransitionedEvents = await unirepContract.queryFilter(userStateTransitionedFilter, startBlock)
const sequencerFilter = unirepContract.filters.Sequencer()
const sequencerEvents = await unirepContract.queryFilter(sequencerFilter, startBlock)
// Reverse the events so pop() can start from the first event
newGSTLeafInsertedEvents.reverse()
attestationSubmittedEvents.reverse()
epochEndedEvents.reverse()
userStateTransitionedEvents.reverse()
for (let i = 0; i < sequencerEvents.length; i++) {
const sequencerEvent = sequencerEvents[i]
const occurredEvent = sequencerEvent.args?._event
if (occurredEvent === "UserSignUp") {
const newLeafEvent = newGSTLeafInsertedEvents.pop()
assert(newLeafEvent !== undefined, `Event sequence mismatch: missing newGSTLeafInsertedEvent`)
const newLeaf = newLeafEvent.args?._hashedLeaf
unirepState.signUp(unirepState.currentEpoch, BigInt(newLeaf))
} else if (occurredEvent === "AttestationSubmitted") {
const attestationEvent = attestationSubmittedEvents.pop()
assert(attestationEvent !== undefined, `Event sequence mismatch: missing attestationSubmittedEvent`)
const epoch = attestationEvent.args?._epoch.toNumber()
assert(
epoch === unirepState.currentEpoch,
`Attestation epoch (${epoch}) does not match current epoch (${unirepState.currentEpoch})`
)
const _attestation = attestationEvent.args?.attestation
const attestation = new Attestation(
BigInt(_attestation.attesterId),
BigInt(_attestation.posRep),
BigInt(_attestation.negRep),
BigInt(_attestation.graffiti),
_attestation.overwriteGraffiti
)
unirepState.addAttestation(attestationEvent.args?._epochKey.toString(), attestation)
} else if (occurredEvent === "EpochEnded") {
const epochEndedEvent = epochEndedEvents.pop()
assert(epochEndedEvent !== undefined, `Event sequence mismatch: missing epochEndedEvent`)
const epoch = epochEndedEvent.args?._epoch.toNumber()
assert(
epoch === unirepState.currentEpoch,
`Ended epoch (${epoch}) does not match current epoch (${unirepState.currentEpoch})`
)
// Get epoch tree leaves of the ending epoch
let [epochKeys_, epochKeyHashchains_] = await unirepContract.getEpochTreeLeaves(epoch)
epochKeys_ = epochKeys_.map((epk) => BigInt(epk.toString()))
epochKeyHashchains_ = epochKeyHashchains_.map((hc) => BigInt(hc.toString()))
const epochTreeLeaves: IEpochTreeLeaf[] = []
for (let i = 0; i < epochKeys_.length; i++) {
const epochTreeLeaf: IEpochTreeLeaf = {
epochKey: epochKeys_[i],
hashchainResult: epochKeyHashchains_[i]
}
epochTreeLeaves.push(epochTreeLeaf)
}
unirepState.epochTransition(epoch, epochTreeLeaves)
} else if (occurredEvent === "UserStateTransitioned") {
const newLeafEvent = newGSTLeafInsertedEvents.pop()
assert(newLeafEvent !== undefined, `Event sequence mismatch: missing newGSTLeafInsertedEvent`)
const userStateTransitionedEvent = userStateTransitionedEvents.pop()
assert(userStateTransitionedEvent !== undefined, `Event sequence mismatch: missing userStateTransitionedEvent`)
const newLeaf = newLeafEvent.args?._hashedLeaf
const isProofValid = await unirepContract.verifyUserStateTransition(
newLeaf,
userStateTransitionedEvent.args?._attestationNullifiers,
userStateTransitionedEvent.args?._epkNullifiers,
userStateTransitionedEvent.args?._fromEpoch,
userStateTransitionedEvent.args?._fromGlobalStateTree,
userStateTransitionedEvent.args?._fromEpochTree,
userStateTransitionedEvent.args?._fromNullifierTreeRoot,
userStateTransitionedEvent.args?._proof,
)
// Proof is invalid, skip this step
if (!isProofValid) {
console.log("Invalid UserStateTransitioned proof")
continue
}
const allNullifiers = userStateTransitionedEvent.args?._attestationNullifiers.map((n) => BigInt(n))
const epkNullifiers = userStateTransitionedEvent.args?._epkNullifiers.map((n) => BigInt(n))
allNullifiers.push(epkNullifiers)
unirepState.userStateTransition(unirepState.currentEpoch, BigInt(newLeaf), allNullifiers)
} else {
throw new Error(`Unexpected event: ${occurredEvent}`)
}
}
assert(newGSTLeafInsertedEvents.length == 0, `${newGSTLeafInsertedEvents.length} newGSTLeafInsert events left unprocessed`)
assert(attestationSubmittedEvents.length == 0, `${attestationSubmittedEvents.length} attestationSubmitted events left unprocessed`)
assert(epochEndedEvents.length == 0, `${epochEndedEvents.length} newGSTLeafInsert events left unprocessed`)
assert(userStateTransitionedEvents.length == 0, `${userStateTransitionedEvents.length} newGSTLeafInsert events left unprocessed`)
return unirepState
}
/*
* Create UserState object from given user state and
* retrieves and parses on-chain Unirep contract data to create an off-chain
* representation as a UserState object (including UnirepState object).
* (This assumes user has already signed up in the Unirep contract)
* @param provider An Ethereum provider
* @param address The address of the Unirep contract
* @param startBlock The block number when Unirep contract is deployed
* @param userIdentity The semaphore identity of the user
* @param userIdentityCommitment Commitment of the userIdentity
* @param latestTransitionedEpoch Latest epoch user has transitioned to
* @param latestGSTLeafIndex Leaf index in the global state tree of the latest epoch user has transitioned to
* @param latestUserStateLeaves User state leaves (empty if no attestations received)
* @param latestEpochKeys User's epoch keys of the epoch user has transitioned to
*/
const genUserStateFromParams = async (
provider: ethers.providers.Provider,
address: string,
startBlock: number,
userIdentity: any,
userIdentityCommitment: any,
latestTransitionedEpoch: number,
latestGSTLeafIndex: number,
latestUserStateLeaves?: IUserStateLeaf[],
) => {
const unirepState = await genUnirepStateFromContract(
provider,
address,
startBlock,
)
const userState = new UserState(
unirepState,
userIdentity,
userIdentityCommitment,
true,
latestTransitionedEpoch,
latestGSTLeafIndex,
latestUserStateLeaves,
)
return userState
}
/*
* This function works mostly the same as genUnirepStateFromContract,
* except that it also updates the user's state during events processing.
* @param provider An Ethereum provider
* @param address The address of the Unirep contract
* @param startBlock The block number when Unirep contract is deployed
* @param userIdentity The semaphore identity of the user
* @param userIdentityCommitment Commitment of the userIdentity
*/
const _genUserStateFromContract = async (
provider: ethers.providers.Provider,
address: string,
startBlock: number,
userIdentity: any,
userIdentityCommitment: any,
) => {
const unirepContract = new ethers.Contract(
address,
Unirep.abi,
provider,
)
const treeDepths_ = await unirepContract.treeDepths()
const globalStateTreeDepth = treeDepths_.globalStateTreeDepth
const userStateTreeDepth = treeDepths_.userStateTreeDepth
const epochTreeDepth = treeDepths_.epochTreeDepth
const nullifierTreeDepth = treeDepths_.nullifierTreeDepth
const attestingFee = await unirepContract.attestingFee()
const epochLength = await unirepContract.epochLength()
const numEpochKeyNoncePerEpoch = await unirepContract.numEpochKeyNoncePerEpoch()
const numAttestationsPerEpochKey = await unirepContract.numAttestationsPerEpochKey()
const unirepState = new UnirepState(
ethers.BigNumber.from(globalStateTreeDepth).toNumber(),
ethers.BigNumber.from(userStateTreeDepth).toNumber(),
ethers.BigNumber.from(epochTreeDepth).toNumber(),
ethers.BigNumber.from(nullifierTreeDepth).toNumber(),
attestingFee,
ethers.BigNumber.from(epochLength).toNumber(),
ethers.BigNumber.from(numEpochKeyNoncePerEpoch).toNumber(),
ethers.BigNumber.from(numAttestationsPerEpochKey).toNumber(),
)
const userState = new UserState(
unirepState,
userIdentity,
userIdentityCommitment,
false,
)
const emptyUserStateRoot = computeEmptyUserStateRoot(unirepState.userStateTreeDepth)
const userDefaultGSTLeaf = hashLeftRight(
userIdentityCommitment,
emptyUserStateRoot
)
const newGSTLeafInsertedFilter = unirepContract.filters.NewGSTLeafInserted()
const newGSTLeafInsertedEvents = await unirepContract.queryFilter(newGSTLeafInsertedFilter, startBlock)
const attestationSubmittedFilter = unirepContract.filters.AttestationSubmitted()
const attestationSubmittedEvents = await unirepContract.queryFilter(attestationSubmittedFilter, startBlock)
const epochEndedFilter = unirepContract.filters.EpochEnded()
const epochEndedEvents = await unirepContract.queryFilter(epochEndedFilter, startBlock)
const userStateTransitionedFilter = unirepContract.filters.UserStateTransitioned()
const userStateTransitionedEvents = await unirepContract.queryFilter(userStateTransitionedFilter, startBlock)
const sequencerFilter = unirepContract.filters.Sequencer()
const sequencerEvents = await unirepContract.queryFilter(sequencerFilter, startBlock)
// Reverse the events so pop() can start from the first event
newGSTLeafInsertedEvents.reverse()
attestationSubmittedEvents.reverse()
epochEndedEvents.reverse()
userStateTransitionedEvents.reverse()
// Variables used to keep track of data required for user to transition
let userHasSignedUp = false
let currentEpochGSTLeafIndexToInsert = 0
let epkNullifiers: BigInt[] = []
for (let i = 0; i < sequencerEvents.length; i++) {
const sequencerEvent = sequencerEvents[i]
const occurredEvent = sequencerEvent.args?._event
if (occurredEvent === "UserSignUp") {
const newLeafEvent = newGSTLeafInsertedEvents.pop()
assert(newLeafEvent !== undefined, `Event sequence mismatch: missing newGSTLeafInsertedEvent`)
const newLeaf = BigInt(newLeafEvent.args?._hashedLeaf)
unirepState.signUp(unirepState.currentEpoch, newLeaf)
// New leaf matches user's default leaf means user signed up.
if (userDefaultGSTLeaf === newLeaf) {
userState.signUp(unirepState.currentEpoch, currentEpochGSTLeafIndexToInsert)
userHasSignedUp = true
}
// A user sign up, increment (next) GST leaf index
currentEpochGSTLeafIndexToInsert ++
} else if (occurredEvent === "AttestationSubmitted") {
const attestationEvent = attestationSubmittedEvents.pop()
assert(attestationEvent !== undefined, `Event sequence mismatch: missing attestationSubmittedEvent`)
const epoch = attestationEvent.args?._epoch.toNumber()
assert(
epoch === unirepState.currentEpoch,
`Attestation epoch (${epoch}) does not match current epoch (${unirepState.currentEpoch})`
)
const _attestation = attestationEvent.args?.attestation
const attestation = new Attestation(
BigInt(_attestation.attesterId),
BigInt(_attestation.posRep),
BigInt(_attestation.negRep),
BigInt(_attestation.graffiti),
_attestation.overwriteGraffiti
)
unirepState.addAttestation(attestationEvent.args?._epochKey.toString(), attestation)
} else if (occurredEvent === "EpochEnded") {
const epochEndedEvent = epochEndedEvents.pop()
assert(epochEndedEvent !== undefined, `Event sequence mismatch: missing epochEndedEvent`)
const epoch = epochEndedEvent.args?._epoch.toNumber()
assert(
epoch === unirepState.currentEpoch,
`Ended epoch (${epoch}) does not match current epoch (${unirepState.currentEpoch})`
)
// Get epoch tree leaves of the ending epoch
let [epochKeys_, epochKeyHashchains_] = await unirepContract.getEpochTreeLeaves(epoch)
epochKeys_ = epochKeys_.map((epk) => BigInt(epk.toString()))
epochKeyHashchains_ = epochKeyHashchains_.map((hc) => BigInt(hc.toString()))
const epochTreeLeaves: IEpochTreeLeaf[] = []
for (let i = 0; i < epochKeys_.length; i++) {
const epochTreeLeaf: IEpochTreeLeaf = {
epochKey: epochKeys_[i],
hashchainResult: epochKeyHashchains_[i]
}
epochTreeLeaves.push(epochTreeLeaf)
}
unirepState.epochTransition(epoch, epochTreeLeaves)
if (userHasSignedUp) {
if (epoch === userState.latestTransitionedEpoch) {
// Latest epoch user transitioned to ends. Generate nullifiers of all epoch key
// so we can identify when user process the epoch keys.
epkNullifiers = userState.getEpochKeyNullifiers(epoch)
}
}
// Epoch ends, reset (next) GST leaf index
currentEpochGSTLeafIndexToInsert = 0
} else if (occurredEvent === "UserStateTransitioned") {
const newLeafEvent = newGSTLeafInsertedEvents.pop()
assert(newLeafEvent !== undefined, `Event sequence mismatch: missing newGSTLeafInsertedEvent`)
const userStateTransitionedEvent = userStateTransitionedEvents.pop()
assert(userStateTransitionedEvent !== undefined, `Event sequence mismatch: missing userStateTransitionedEvent`)
const newLeaf = newLeafEvent.args?._hashedLeaf
const isProofValid = await unirepContract.verifyUserStateTransition(
newLeaf,
userStateTransitionedEvent.args?._attestationNullifiers,
userStateTransitionedEvent.args?._epkNullifiers,
userStateTransitionedEvent.args?._fromEpoch,
userStateTransitionedEvent.args?._fromGlobalStateTree,
userStateTransitionedEvent.args?._fromEpochTree,
userStateTransitionedEvent.args?._fromNullifierTreeRoot,
userStateTransitionedEvent.args?._proof,
)
// Proof is invalid, skip this event
if (!isProofValid) {
console.log("Invalid UserStateTransitioned proof")
continue
}
const allNullifiers = userStateTransitionedEvent.args?._attestationNullifiers.map((n) => BigInt(n))
const _epkNullifiers = userStateTransitionedEvent.args?._epkNullifiers.map((n) => BigInt(n))
allNullifiers.push(_epkNullifiers)
if (
userHasSignedUp &&
(userStateTransitionedEvent.args?._fromEpoch.toNumber() === userState.latestTransitionedEpoch)
) {
let epkNullifiersMatched = 0
for (const nullifier of epkNullifiers) {
if (_epkNullifiers.indexOf(nullifier) !== -1) epkNullifiersMatched++
}
if (epkNullifiersMatched == userState.numEpochKeyNoncePerEpoch) {
const newState = await userState.genNewUserStateAfterTransition()
userState.transition(newState.newUSTLeaves)
// User processed all epoch keys so non-zero GST leaf is generated.
assert(BigNumber.from(newState.newGSTLeaf).eq(newLeaf), 'New GST leaf mismatch')
// User transition to this epoch, increment (next) GST leaf index
currentEpochGSTLeafIndexToInsert ++
} else if (epkNullifiersMatched > 0) {
throw new Error(`Number of epoch key nullifiers matched ${epkNullifiersMatched} not equal to numEpochKeyNoncePerEpoch ${numEpochKeyNoncePerEpoch}`)
}
}
unirepState.userStateTransition(unirepState.currentEpoch, BigInt(newLeaf), allNullifiers)
} else {
throw new Error(`Unexpected event: ${occurredEvent}`)
}
}
assert(userHasSignedUp, "User did not sign up")
assert(newGSTLeafInsertedEvents.length == 0, `${newGSTLeafInsertedEvents.length} newGSTLeafInsert events left unprocessed`)
assert(attestationSubmittedEvents.length == 0, `${attestationSubmittedEvents.length} attestationSubmitted events left unprocessed`)
assert(epochEndedEvents.length == 0, `${epochEndedEvents.length} newGSTLeafInsert events left unprocessed`)
assert(userStateTransitionedEvents.length == 0, `${userStateTransitionedEvents.length} newGSTLeafInsert events left unprocessed`)
return userState
}
/*
* Given user identity and userIdentityCommitment, retrieves and parses on-chain
* Unirep contract data to create an off-chain representation as a
* UserState object (including UnirepState object).
* @param provider An Ethereum provider
* @param address The address of the Unirep contract
* @param startBlock The block number when Unirep contract is deployed
* @param userIdentity The semaphore identity of the user
* @param userIdentityCommitment Commitment of the userIdentity
*/
const genUserStateFromContract = async (
provider: ethers.providers.Provider,
address: string,
startBlock: number,
userIdentity: any,
userIdentityCommitment: any,
) => {
return await _genUserStateFromContract(
provider,
address,
startBlock,
userIdentity,
userIdentityCommitment,
)
}
export {
genUnirepStateFromContract,
genUserStateFromContract,
genUserStateFromParams,
}