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
|
/*
This file is part of GNU Taler
(C) 2019-2020 Taler Systems SA
GNU Taler is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3, or (at your option) any later version.
GNU Taler 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 General Public License for more details.
You should have received a copy of the GNU General Public License along with
GNU Taler; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
*/
/**
* Implementation of the recoup operation, which allows to recover the
* value of coins held in a revoked denomination.
*
* @author Florian Dold <dold@taler.net>
*/
/**
* Imports.
*/
import {
Amounts,
codecForRecoupConfirmation,
codecForReserveStatus,
CoinStatus,
encodeCrock,
getRandomBytes,
j2s,
Logger,
NotificationType,
RefreshReason,
TalerProtocolTimestamp,
TalerPreciseTimestamp,
URL,
} from "@gnu-taler/taler-util";
import {
CoinRecord,
CoinSourceType,
RecoupGroupRecord,
RefreshCoinSource,
WalletStoresV1,
WithdrawalGroupStatus,
WithdrawalRecordType,
WithdrawCoinSource,
} from "../db.js";
import { InternalWalletState } from "../internal-wallet-state.js";
import { readSuccessResponseJsonOrThrow } from "@gnu-taler/taler-util/http";
import { checkDbInvariant } from "../util/invariants.js";
import { GetReadWriteAccess } from "../util/query.js";
import { createRefreshGroup, processRefreshGroup } from "./refresh.js";
import { internalCreateWithdrawalGroup } from "./withdraw.js";
import { OperationAttemptResult } from "./common.js";
const logger = new Logger("operations/recoup.ts");
/**
* Store a recoup group record in the database after marking
* a coin in the group as finished.
*/
async function putGroupAsFinished(
ws: InternalWalletState,
tx: GetReadWriteAccess<{
recoupGroups: typeof WalletStoresV1.recoupGroups;
denominations: typeof WalletStoresV1.denominations;
refreshGroups: typeof WalletStoresV1.refreshGroups;
coins: typeof WalletStoresV1.coins;
}>,
recoupGroup: RecoupGroupRecord,
coinIdx: number,
): Promise<void> {
logger.trace(
`setting coin ${coinIdx} of ${recoupGroup.coinPubs.length} as finished`,
);
if (recoupGroup.timestampFinished) {
return;
}
recoupGroup.recoupFinishedPerCoin[coinIdx] = true;
await tx.recoupGroups.put(recoupGroup);
}
async function recoupTipCoin(
ws: InternalWalletState,
recoupGroupId: string,
coinIdx: number,
coin: CoinRecord,
): Promise<void> {
// We can't really recoup a coin we got via tipping.
// Thus we just put the coin to sleep.
// FIXME: somehow report this to the user
await ws.db
.mktx((stores) => [
stores.recoupGroups,
stores.denominations,
stores.refreshGroups,
stores.coins,
])
.runReadWrite(async (tx) => {
const recoupGroup = await tx.recoupGroups.get(recoupGroupId);
if (!recoupGroup) {
return;
}
if (recoupGroup.recoupFinishedPerCoin[coinIdx]) {
return;
}
await putGroupAsFinished(ws, tx, recoupGroup, coinIdx);
});
}
async function recoupWithdrawCoin(
ws: InternalWalletState,
recoupGroupId: string,
coinIdx: number,
coin: CoinRecord,
cs: WithdrawCoinSource,
): Promise<void> {
const reservePub = cs.reservePub;
const denomInfo = await ws.db
.mktx((x) => [x.denominations])
.runReadOnly(async (tx) => {
const denomInfo = await ws.getDenomInfo(
ws,
tx,
coin.exchangeBaseUrl,
coin.denomPubHash,
);
return denomInfo;
});
if (!denomInfo) {
// FIXME: We should at least emit some pending operation / warning for this?
return;
}
const recoupRequest = await ws.cryptoApi.createRecoupRequest({
blindingKey: coin.blindingKey,
coinPriv: coin.coinPriv,
coinPub: coin.coinPub,
denomPub: denomInfo.denomPub,
denomPubHash: coin.denomPubHash,
denomSig: coin.denomSig,
});
const reqUrl = new URL(`/coins/${coin.coinPub}/recoup`, coin.exchangeBaseUrl);
logger.trace(`requesting recoup via ${reqUrl.href}`);
const resp = await ws.http.postJson(reqUrl.href, recoupRequest);
const recoupConfirmation = await readSuccessResponseJsonOrThrow(
resp,
codecForRecoupConfirmation(),
);
logger.trace(`got recoup confirmation ${j2s(recoupConfirmation)}`);
if (recoupConfirmation.reserve_pub !== reservePub) {
throw Error(`Coin's reserve doesn't match reserve on recoup`);
}
// FIXME: verify that our expectations about the amount match
await ws.db
.mktx((x) => [x.coins, x.denominations, x.recoupGroups, x.refreshGroups])
.runReadWrite(async (tx) => {
const recoupGroup = await tx.recoupGroups.get(recoupGroupId);
if (!recoupGroup) {
return;
}
if (recoupGroup.recoupFinishedPerCoin[coinIdx]) {
return;
}
const updatedCoin = await tx.coins.get(coin.coinPub);
if (!updatedCoin) {
return;
}
updatedCoin.status = CoinStatus.Dormant;
await tx.coins.put(updatedCoin);
await putGroupAsFinished(ws, tx, recoupGroup, coinIdx);
});
}
async function recoupRefreshCoin(
ws: InternalWalletState,
recoupGroupId: string,
coinIdx: number,
coin: CoinRecord,
cs: RefreshCoinSource,
): Promise<void> {
const d = await ws.db
.mktx((x) => [x.coins, x.denominations])
.runReadOnly(async (tx) => {
const denomInfo = await ws.getDenomInfo(
ws,
tx,
coin.exchangeBaseUrl,
coin.denomPubHash,
);
if (!denomInfo) {
return;
}
return { denomInfo };
});
if (!d) {
// FIXME: We should at least emit some pending operation / warning for this?
return;
}
const recoupRequest = await ws.cryptoApi.createRecoupRefreshRequest({
blindingKey: coin.blindingKey,
coinPriv: coin.coinPriv,
coinPub: coin.coinPub,
denomPub: d.denomInfo.denomPub,
denomPubHash: coin.denomPubHash,
denomSig: coin.denomSig,
});
const reqUrl = new URL(
`/coins/${coin.coinPub}/recoup-refresh`,
coin.exchangeBaseUrl,
);
logger.trace(`making recoup request for ${coin.coinPub}`);
const resp = await ws.http.postJson(reqUrl.href, recoupRequest);
const recoupConfirmation = await readSuccessResponseJsonOrThrow(
resp,
codecForRecoupConfirmation(),
);
if (recoupConfirmation.old_coin_pub != cs.oldCoinPub) {
throw Error(`Coin's oldCoinPub doesn't match reserve on recoup`);
}
await ws.db
.mktx((x) => [x.coins, x.denominations, x.recoupGroups, x.refreshGroups])
.runReadWrite(async (tx) => {
const recoupGroup = await tx.recoupGroups.get(recoupGroupId);
if (!recoupGroup) {
return;
}
if (recoupGroup.recoupFinishedPerCoin[coinIdx]) {
return;
}
const oldCoin = await tx.coins.get(cs.oldCoinPub);
const revokedCoin = await tx.coins.get(coin.coinPub);
if (!revokedCoin) {
logger.warn("revoked coin for recoup not found");
return;
}
if (!oldCoin) {
logger.warn("refresh old coin for recoup not found");
return;
}
const oldCoinDenom = await ws.getDenomInfo(
ws,
tx,
oldCoin.exchangeBaseUrl,
oldCoin.denomPubHash,
);
const revokedCoinDenom = await ws.getDenomInfo(
ws,
tx,
revokedCoin.exchangeBaseUrl,
revokedCoin.denomPubHash,
);
checkDbInvariant(!!oldCoinDenom);
checkDbInvariant(!!revokedCoinDenom);
revokedCoin.status = CoinStatus.Dormant;
if (!revokedCoin.spendAllocation) {
// We don't know what happened to this coin
logger.error(
`can't refresh-recoup coin ${revokedCoin.coinPub}, no spendAllocation known`,
);
} else {
let residualAmount = Amounts.sub(
revokedCoinDenom.value,
revokedCoin.spendAllocation.amount,
).amount;
recoupGroup.scheduleRefreshCoins.push({
coinPub: oldCoin.coinPub,
amount: Amounts.stringify(residualAmount),
});
}
await tx.coins.put(revokedCoin);
await tx.coins.put(oldCoin);
await putGroupAsFinished(ws, tx, recoupGroup, coinIdx);
});
}
export async function processRecoupGroup(
ws: InternalWalletState,
recoupGroupId: string,
): Promise<OperationAttemptResult> {
let recoupGroup = await ws.db
.mktx((x) => [x.recoupGroups])
.runReadOnly(async (tx) => {
return tx.recoupGroups.get(recoupGroupId);
});
if (!recoupGroup) {
return OperationAttemptResult.finishedEmpty();
}
if (recoupGroup.timestampFinished) {
logger.trace("recoup group finished");
return OperationAttemptResult.finishedEmpty();
}
const ps = recoupGroup.coinPubs.map(async (x, i) => {
try {
await processRecoup(ws, recoupGroupId, i);
} catch (e) {
logger.warn(`processRecoup failed: ${e}`);
throw e;
}
});
await Promise.all(ps);
recoupGroup = await ws.db
.mktx((x) => [x.recoupGroups])
.runReadOnly(async (tx) => {
return tx.recoupGroups.get(recoupGroupId);
});
if (!recoupGroup) {
return OperationAttemptResult.finishedEmpty();
}
for (const b of recoupGroup.recoupFinishedPerCoin) {
if (!b) {
return OperationAttemptResult.finishedEmpty();
}
}
logger.info("all recoups of recoup group are finished");
const reserveSet = new Set<string>();
const reservePrivMap: Record<string, string> = {};
for (let i = 0; i < recoupGroup.coinPubs.length; i++) {
const coinPub = recoupGroup.coinPubs[i];
await ws.db
.mktx((x) => [x.coins, x.reserves])
.runReadOnly(async (tx) => {
const coin = await tx.coins.get(coinPub);
if (!coin) {
throw Error(`Coin ${coinPub} not found, can't request recoup`);
}
if (coin.coinSource.type === CoinSourceType.Withdraw) {
const reserve = await tx.reserves.indexes.byReservePub.get(
coin.coinSource.reservePub,
);
if (!reserve) {
return;
}
reserveSet.add(coin.coinSource.reservePub);
reservePrivMap[coin.coinSource.reservePub] = reserve.reservePriv;
}
});
}
for (const reservePub of reserveSet) {
const reserveUrl = new URL(
`reserves/${reservePub}`,
recoupGroup.exchangeBaseUrl,
);
logger.info(`querying reserve status for recoup via ${reserveUrl}`);
const resp = await ws.http.get(reserveUrl.href);
const result = await readSuccessResponseJsonOrThrow(
resp,
codecForReserveStatus(),
);
await internalCreateWithdrawalGroup(ws, {
amount: Amounts.parseOrThrow(result.balance),
exchangeBaseUrl: recoupGroup.exchangeBaseUrl,
reserveStatus: WithdrawalGroupStatus.PendingQueryingStatus,
reserveKeyPair: {
pub: reservePub,
priv: reservePrivMap[reservePub],
},
wgInfo: {
withdrawalType: WithdrawalRecordType.Recoup,
},
});
}
await ws.db
.mktx((x) => [
x.recoupGroups,
x.coinAvailability,
x.denominations,
x.refreshGroups,
x.coins,
])
.runReadWrite(async (tx) => {
const rg2 = await tx.recoupGroups.get(recoupGroupId);
if (!rg2) {
return;
}
rg2.timestampFinished = TalerPreciseTimestamp.now();
if (rg2.scheduleRefreshCoins.length > 0) {
const refreshGroupId = await createRefreshGroup(
ws,
tx,
Amounts.currencyOf(rg2.scheduleRefreshCoins[0].amount),
rg2.scheduleRefreshCoins,
RefreshReason.Recoup,
);
processRefreshGroup(ws, refreshGroupId.refreshGroupId).catch((e) => {
logger.error(`error while refreshing after recoup ${e}`);
});
}
await tx.recoupGroups.put(rg2);
});
return OperationAttemptResult.finishedEmpty();
}
export async function createRecoupGroup(
ws: InternalWalletState,
tx: GetReadWriteAccess<{
recoupGroups: typeof WalletStoresV1.recoupGroups;
denominations: typeof WalletStoresV1.denominations;
refreshGroups: typeof WalletStoresV1.refreshGroups;
coins: typeof WalletStoresV1.coins;
}>,
exchangeBaseUrl: string,
coinPubs: string[],
): Promise<string> {
const recoupGroupId = encodeCrock(getRandomBytes(32));
const recoupGroup: RecoupGroupRecord = {
recoupGroupId,
exchangeBaseUrl: exchangeBaseUrl,
coinPubs: coinPubs,
timestampFinished: undefined,
timestampStarted: TalerPreciseTimestamp.now(),
recoupFinishedPerCoin: coinPubs.map(() => false),
scheduleRefreshCoins: [],
};
for (let coinIdx = 0; coinIdx < coinPubs.length; coinIdx++) {
const coinPub = coinPubs[coinIdx];
const coin = await tx.coins.get(coinPub);
if (!coin) {
await putGroupAsFinished(ws, tx, recoupGroup, coinIdx);
continue;
}
await tx.coins.put(coin);
}
await tx.recoupGroups.put(recoupGroup);
return recoupGroupId;
}
/**
* Run the recoup protocol for a single coin in a recoup group.
*/
async function processRecoup(
ws: InternalWalletState,
recoupGroupId: string,
coinIdx: number,
): Promise<void> {
const coin = await ws.db
.mktx((x) => [x.recoupGroups, x.coins])
.runReadOnly(async (tx) => {
const recoupGroup = await tx.recoupGroups.get(recoupGroupId);
if (!recoupGroup) {
return;
}
if (recoupGroup.timestampFinished) {
return;
}
if (recoupGroup.recoupFinishedPerCoin[coinIdx]) {
return;
}
const coinPub = recoupGroup.coinPubs[coinIdx];
const coin = await tx.coins.get(coinPub);
if (!coin) {
throw Error(`Coin ${coinPub} not found, can't request recoup`);
}
return coin;
});
if (!coin) {
return;
}
const cs = coin.coinSource;
switch (cs.type) {
case CoinSourceType.Tip:
return recoupTipCoin(ws, recoupGroupId, coinIdx, coin);
case CoinSourceType.Refresh:
return recoupRefreshCoin(ws, recoupGroupId, coinIdx, coin, cs);
case CoinSourceType.Withdraw:
return recoupWithdrawCoin(ws, recoupGroupId, coinIdx, coin, cs);
default:
throw Error("unknown coin source type");
}
}
|