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
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
|
/*
This file is part of TALER
Copyright (C) 2015-2021 Taler Systems SA
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.
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
TALER; see the file COPYING. If not, see
<http://www.gnu.org/licenses/>
*/
/**
* @file lib/exchange_api_common.c
* @brief common functions for the exchange API
* @author Christian Grothoff
*/
#include "platform.h"
#include "taler_json_lib.h"
#include <gnunet/gnunet_curl_lib.h>
#include "exchange_api_handle.h"
#include "taler_signatures.h"
enum GNUNET_GenericReturnValue
TALER_EXCHANGE_parse_reserve_history (
struct TALER_EXCHANGE_Handle *exchange,
const json_t *history,
const struct TALER_ReservePublicKeyP *reserve_pub,
const char *currency,
struct TALER_Amount *total_in,
struct TALER_Amount *total_out,
unsigned int history_length,
struct TALER_EXCHANGE_ReserveHistoryEntry *rhistory)
{
struct GNUNET_HashCode uuid[history_length];
unsigned int uuid_off;
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (currency,
total_in));
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (currency,
total_out));
uuid_off = 0;
for (unsigned int off = 0; off<history_length; off++)
{
struct TALER_EXCHANGE_ReserveHistoryEntry *rh = &rhistory[off];
json_t *transaction;
struct TALER_Amount amount;
const char *type;
struct GNUNET_JSON_Specification hist_spec[] = {
GNUNET_JSON_spec_string ("type",
&type),
TALER_JSON_spec_amount_any ("amount",
&amount),
/* 'wire' and 'signature' are optional depending on 'type'! */
GNUNET_JSON_spec_end ()
};
transaction = json_array_get (history,
off);
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
hist_spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
rhistory[off].amount = amount;
if (GNUNET_YES !=
TALER_amount_cmp_currency (&amount,
total_in))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (0 == strcasecmp (type,
"CREDIT"))
{
const char *wire_url;
uint64_t wire_reference;
struct GNUNET_TIME_Timestamp timestamp;
struct GNUNET_JSON_Specification withdraw_spec[] = {
GNUNET_JSON_spec_uint64 ("wire_reference",
&wire_reference),
GNUNET_JSON_spec_timestamp ("timestamp",
×tamp),
GNUNET_JSON_spec_string ("sender_account_url",
&wire_url),
GNUNET_JSON_spec_end ()
};
rh->type = TALER_EXCHANGE_RTT_CREDIT;
if (0 >
TALER_amount_add (total_in,
total_in,
&amount))
{
/* overflow in history already!? inconceivable! Bad exchange! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
withdraw_spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
rh->details.in_details.sender_url = GNUNET_strdup (wire_url);
rh->details.in_details.wire_reference = wire_reference;
rh->details.in_details.timestamp = timestamp;
/* end type==DEPOSIT */
}
else if (0 == strcasecmp (type,
"WITHDRAW"))
{
struct TALER_ReserveSignatureP sig;
struct TALER_DenominationHashP h_denom_pub;
struct TALER_BlindedCoinHashP bch;
struct TALER_Amount withdraw_fee;
struct GNUNET_JSON_Specification withdraw_spec[] = {
GNUNET_JSON_spec_fixed_auto ("reserve_sig",
&sig),
TALER_JSON_spec_amount_any ("withdraw_fee",
&withdraw_fee),
GNUNET_JSON_spec_fixed_auto ("h_denom_pub",
&h_denom_pub),
GNUNET_JSON_spec_fixed_auto ("h_coin_envelope",
&bch),
GNUNET_JSON_spec_end ()
};
rh->type = TALER_EXCHANGE_RTT_WITHDRAWAL;
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
withdraw_spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
/* Check that the signature is a valid withdraw request */
if (GNUNET_OK !=
TALER_wallet_withdraw_verify (&h_denom_pub,
&amount,
&bch,
reserve_pub,
&sig))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (withdraw_spec);
return GNUNET_SYSERR;
}
/* check that withdraw fee matches expectations! */
{
const struct TALER_EXCHANGE_Keys *key_state;
const struct TALER_EXCHANGE_DenomPublicKey *dki;
key_state = TALER_EXCHANGE_get_keys (exchange);
dki = TALER_EXCHANGE_get_denomination_key_by_hash (key_state,
&h_denom_pub);
if ( (GNUNET_YES !=
TALER_amount_cmp_currency (&withdraw_fee,
&dki->fees.withdraw)) ||
(0 !=
TALER_amount_cmp (&withdraw_fee,
&dki->fees.withdraw)) )
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (withdraw_spec);
return GNUNET_SYSERR;
}
rh->details.withdraw.fee = withdraw_fee;
}
rh->details.withdraw.out_authorization_sig
= json_object_get (transaction,
"signature");
/* Check check that the same withdraw transaction
isn't listed twice by the exchange. We use the
"uuid" array to remember the hashes of all
signatures, and compare the hashes to find
duplicates. */
GNUNET_CRYPTO_hash (&sig,
sizeof (sig),
&uuid[uuid_off]);
for (unsigned int i = 0; i<uuid_off; i++)
{
if (0 == GNUNET_memcmp (&uuid[uuid_off],
&uuid[i]))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (withdraw_spec);
return GNUNET_SYSERR;
}
}
uuid_off++;
if (0 >
TALER_amount_add (total_out,
total_out,
&amount))
{
/* overflow in history already!? inconceivable! Bad exchange! */
GNUNET_break_op (0);
GNUNET_JSON_parse_free (withdraw_spec);
return GNUNET_SYSERR;
}
/* end type==WITHDRAW */
}
else if (0 == strcasecmp (type,
"RECOUP"))
{
const struct TALER_EXCHANGE_Keys *key_state;
struct GNUNET_JSON_Specification recoup_spec[] = {
GNUNET_JSON_spec_fixed_auto ("coin_pub",
&rh->details.recoup_details.coin_pub),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&rh->details.recoup_details.exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&rh->details.recoup_details.exchange_pub),
GNUNET_JSON_spec_timestamp ("timestamp",
&rh->details.recoup_details.timestamp),
GNUNET_JSON_spec_end ()
};
rh->type = TALER_EXCHANGE_RTT_RECOUP;
rh->amount = amount;
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
recoup_spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
key_state = TALER_EXCHANGE_get_keys (exchange);
if (GNUNET_OK !=
TALER_EXCHANGE_test_signing_key (key_state,
&rh->details.
recoup_details.exchange_pub))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_exchange_online_confirm_recoup_verify (
rh->details.recoup_details.timestamp,
&amount,
&rh->details.recoup_details.coin_pub,
reserve_pub,
&rh->details.recoup_details.exchange_pub,
&rh->details.recoup_details.exchange_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (0 >
TALER_amount_add (total_in,
total_in,
&rh->amount))
{
/* overflow in history already!? inconceivable! Bad exchange! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
/* end type==RECOUP */
}
else if (0 == strcasecmp (type,
"CLOSING"))
{
const struct TALER_EXCHANGE_Keys *key_state;
struct GNUNET_JSON_Specification closing_spec[] = {
GNUNET_JSON_spec_string (
"receiver_account_details",
&rh->details.close_details.receiver_account_details),
GNUNET_JSON_spec_fixed_auto ("wtid",
&rh->details.close_details.wtid),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&rh->details.close_details.exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&rh->details.close_details.exchange_pub),
TALER_JSON_spec_amount_any ("closing_fee",
&rh->details.close_details.fee),
GNUNET_JSON_spec_timestamp ("timestamp",
&rh->details.close_details.timestamp),
GNUNET_JSON_spec_end ()
};
rh->type = TALER_EXCHANGE_RTT_CLOSE;
rh->amount = amount;
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
closing_spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
key_state = TALER_EXCHANGE_get_keys (exchange);
if (GNUNET_OK !=
TALER_EXCHANGE_test_signing_key (
key_state,
&rh->details.close_details.exchange_pub))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_exchange_online_reserve_closed_verify (
rh->details.close_details.timestamp,
&amount,
&rh->details.close_details.fee,
rh->details.close_details.receiver_account_details,
&rh->details.close_details.wtid,
reserve_pub,
&rh->details.close_details.exchange_pub,
&rh->details.close_details.exchange_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (0 >
TALER_amount_add (total_out,
total_out,
&rh->amount))
{
/* overflow in history already!? inconceivable! Bad exchange! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
/* end type==CLOSING */
}
else
{
/* unexpected 'type', protocol incompatibility, complain! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
}
return GNUNET_OK;
}
void
TALER_EXCHANGE_free_reserve_history (
struct TALER_EXCHANGE_ReserveHistoryEntry *rhistory,
unsigned int len)
{
for (unsigned int i = 0; i<len; i++)
{
switch (rhistory[i].type)
{
case TALER_EXCHANGE_RTT_CREDIT:
GNUNET_free (rhistory[i].details.in_details.sender_url);
break;
case TALER_EXCHANGE_RTT_WITHDRAWAL:
break;
case TALER_EXCHANGE_RTT_RECOUP:
break;
case TALER_EXCHANGE_RTT_CLOSE:
break;
}
}
GNUNET_free (rhistory);
}
enum GNUNET_GenericReturnValue
TALER_EXCHANGE_verify_coin_history (
const struct TALER_EXCHANGE_DenomPublicKey *dk,
const char *currency,
const struct TALER_CoinSpendPublicKeyP *coin_pub,
json_t *history,
struct TALER_DenominationHashP *h_denom_pub,
struct TALER_Amount *total)
{
size_t len;
struct TALER_Amount rtotal;
struct TALER_Amount fee;
if (NULL == history)
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
len = json_array_size (history);
if (0 == len)
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (currency,
total));
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (currency,
&rtotal));
for (size_t off = 0; off<len; off++)
{
int add;
json_t *transaction;
struct TALER_Amount amount;
const char *type;
struct GNUNET_JSON_Specification spec_glob[] = {
TALER_JSON_spec_amount_any ("amount",
&amount),
GNUNET_JSON_spec_string ("type",
&type),
GNUNET_JSON_spec_end ()
};
transaction = json_array_get (history,
off);
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec_glob,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_YES !=
TALER_amount_cmp_currency (&amount,
&rtotal))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
add = GNUNET_SYSERR;
if (0 == strcasecmp (type,
"DEPOSIT"))
{
struct TALER_MerchantWireHashP h_wire;
struct TALER_PrivateContractHashP h_contract_terms;
// struct TALER_ExtensionContractHashP h_extensions; // FIXME!
struct GNUNET_TIME_Timestamp wallet_timestamp;
struct TALER_MerchantPublicKeyP merchant_pub;
struct GNUNET_TIME_Timestamp refund_deadline = {0};
struct TALER_CoinSpendSignatureP sig;
struct TALER_AgeCommitmentHash hac = {0};
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("coin_sig",
&sig),
GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
&h_contract_terms),
GNUNET_JSON_spec_fixed_auto ("h_wire",
&h_wire),
GNUNET_JSON_spec_fixed_auto ("h_denom_pub",
h_denom_pub),
GNUNET_JSON_spec_mark_optional (
GNUNET_JSON_spec_fixed_auto ("h_age_commitment",
&hac)),
GNUNET_JSON_spec_timestamp ("timestamp",
&wallet_timestamp),
GNUNET_JSON_spec_mark_optional (
GNUNET_JSON_spec_timestamp ("refund_deadline",
&refund_deadline)),
TALER_JSON_spec_amount_any ("deposit_fee",
&fee),
GNUNET_JSON_spec_fixed_auto ("merchant_pub",
&merchant_pub),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_wallet_deposit_verify (
&amount,
&fee,
&h_wire,
&h_contract_terms,
TALER_AgeCommitmentHash_isNullOrZero (&hac) ? NULL : &hac,
NULL /* h_extensions! */,
h_denom_pub,
wallet_timestamp,
&merchant_pub,
refund_deadline,
coin_pub,
&sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (NULL != dk)
{
/* check that deposit fee matches our expectations from /keys! */
if ( (GNUNET_YES !=
TALER_amount_cmp_currency (&fee,
&dk->fees.deposit)) ||
(0 !=
TALER_amount_cmp (&fee,
&dk->fees.deposit)) )
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
}
add = GNUNET_YES;
}
else if (0 == strcasecmp (type,
"MELT"))
{
struct TALER_CoinSpendSignatureP sig;
struct TALER_RefreshCommitmentP rc;
struct TALER_AgeCommitmentHash h_age_commitment = {0};
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("coin_sig",
&sig),
GNUNET_JSON_spec_fixed_auto ("rc",
&rc),
GNUNET_JSON_spec_fixed_auto ("h_denom_pub",
h_denom_pub),
GNUNET_JSON_spec_mark_optional (
GNUNET_JSON_spec_fixed_auto ("h_age_commitment",
&h_age_commitment)),
TALER_JSON_spec_amount_any ("melt_fee",
&fee),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (NULL != dk)
{
/* check that melt fee matches our expectations from /keys! */
if ( (GNUNET_YES !=
TALER_amount_cmp_currency (&fee,
&dk->fees.refresh)) ||
(0 !=
TALER_amount_cmp (&fee,
&dk->fees.refresh)) )
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
}
if (GNUNET_OK !=
TALER_wallet_melt_verify (
&amount,
&fee,
&rc,
h_denom_pub,
TALER_AgeCommitmentHash_isNullOrZero (&h_age_commitment) ?
NULL : &h_age_commitment,
coin_pub,
&sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
add = GNUNET_YES;
}
else if (0 == strcasecmp (type,
"REFUND"))
{
struct TALER_PrivateContractHashP h_contract_terms;
struct TALER_MerchantPublicKeyP merchant_pub;
struct TALER_MerchantSignatureP sig;
struct TALER_Amount refund_fee;
struct TALER_Amount sig_amount;
uint64_t rtransaction_id;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount_any ("refund_fee",
&refund_fee),
GNUNET_JSON_spec_fixed_auto ("merchant_sig",
&sig),
GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
&h_contract_terms),
GNUNET_JSON_spec_fixed_auto ("merchant_pub",
&merchant_pub),
GNUNET_JSON_spec_uint64 ("rtransaction_id",
&rtransaction_id),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (0 >
TALER_amount_add (&sig_amount,
&refund_fee,
&amount))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_merchant_refund_verify (coin_pub,
&h_contract_terms,
rtransaction_id,
&sig_amount,
&merchant_pub,
&sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
/* NOTE: theoretically, we could also check that the given
merchant_pub and h_contract_terms appear in the
history under deposits. However, there is really no benefit
for the exchange to lie here, so not checking is probably OK
(an auditor ought to check, though). Then again, we similarly
had no reason to check the merchant's signature (other than a
well-formendess check). */
/* check that refund fee matches our expectations from /keys! */
if (NULL != dk)
{
if ( (GNUNET_YES !=
TALER_amount_cmp_currency (&refund_fee,
&dk->fees.refund)) ||
(0 !=
TALER_amount_cmp (&refund_fee,
&dk->fees.refund)) )
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
}
add = GNUNET_NO;
}
else if (0 == strcasecmp (type,
"RECOUP"))
{
struct TALER_ReservePublicKeyP reserve_pub;
struct GNUNET_TIME_Timestamp timestamp;
union TALER_DenominationBlindingKeyP coin_bks;
struct TALER_ExchangePublicKeyP exchange_pub;
struct TALER_ExchangeSignatureP exchange_sig;
struct TALER_CoinSpendSignatureP coin_sig;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount_any ("amount",
&amount),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&exchange_pub),
GNUNET_JSON_spec_fixed_auto ("reserve_pub",
&reserve_pub),
GNUNET_JSON_spec_fixed_auto ("coin_sig",
&coin_sig),
GNUNET_JSON_spec_fixed_auto ("coin_blind",
&coin_bks),
GNUNET_JSON_spec_fixed_auto ("h_denom_pub",
h_denom_pub),
GNUNET_JSON_spec_timestamp ("timestamp",
×tamp),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_exchange_online_confirm_recoup_verify (
timestamp,
&amount,
coin_pub,
&reserve_pub,
&exchange_pub,
&exchange_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_wallet_recoup_verify (h_denom_pub,
&coin_bks,
coin_pub,
&coin_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
add = GNUNET_YES;
}
else if (0 == strcasecmp (type,
"RECOUP-REFRESH"))
{
/* This is the coin that was subjected to a recoup,
the value being credited to the old coin. */
struct TALER_CoinSpendPublicKeyP old_coin_pub;
union TALER_DenominationBlindingKeyP coin_bks;
struct TALER_Amount amount;
struct GNUNET_TIME_Timestamp timestamp;
struct TALER_ExchangePublicKeyP exchange_pub;
struct TALER_ExchangeSignatureP exchange_sig;
struct TALER_CoinSpendSignatureP coin_sig;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount_any ("amount",
&amount),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&exchange_pub),
GNUNET_JSON_spec_fixed_auto ("coin_sig",
&coin_sig),
GNUNET_JSON_spec_fixed_auto ("old_coin_pub",
&old_coin_pub),
GNUNET_JSON_spec_fixed_auto ("coin_blind",
&coin_bks),
GNUNET_JSON_spec_fixed_auto ("h_denom_pub",
h_denom_pub),
GNUNET_JSON_spec_timestamp ("timestamp",
×tamp),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_exchange_online_confirm_recoup_refresh_verify (
timestamp,
&amount,
coin_pub,
&old_coin_pub,
&exchange_pub,
&exchange_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_wallet_recoup_verify (h_denom_pub,
&coin_bks,
coin_pub,
&coin_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
add = GNUNET_YES;
}
else if (0 == strcasecmp (type,
"OLD-COIN-RECOUP"))
{
/* This is the coin that was credited in a recoup,
the value being credited to the this coin. */
struct TALER_ExchangePublicKeyP exchange_pub;
struct TALER_ExchangeSignatureP exchange_sig;
struct TALER_CoinSpendPublicKeyP new_coin_pub;
struct GNUNET_TIME_Timestamp timestamp;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount_any ("amount",
&amount),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&exchange_pub),
GNUNET_JSON_spec_fixed_auto ("coin_pub",
&new_coin_pub),
GNUNET_JSON_spec_timestamp ("timestamp",
×tamp),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (transaction,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_exchange_online_confirm_recoup_refresh_verify (
timestamp,
&amount,
&new_coin_pub,
coin_pub,
&exchange_pub,
&exchange_sig))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
add = GNUNET_NO;
}
else if (0 == strcasecmp (type,
"LOCK_NONCE"))
{
GNUNET_break (0); // FIXME: implement!
}
else
{
/* signature not supported, new version on server? */
GNUNET_break_op (0);
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Unexpected type `%s' in response\n",
type);
GNUNET_assert (GNUNET_SYSERR == add);
return GNUNET_SYSERR;
}
if (GNUNET_YES == add)
{
/* This amount should be added to the total */
if (0 >
TALER_amount_add (total,
total,
&amount))
{
/* overflow in history already!? inconceivable! Bad exchange! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
}
else
{
/* This amount should be subtracted from the total.
However, for the implementation, we first *add* up all of
these negative amounts, as we might get refunds before
deposits from a semi-evil exchange. Then, at the end, we do
the subtraction by calculating "total = total - rtotal" */
GNUNET_assert (GNUNET_NO == add);
if (0 >
TALER_amount_add (&rtotal,
&rtotal,
&amount))
{
/* overflow in refund history? inconceivable! Bad exchange! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
}
}
/* Finally, subtract 'rtotal' from total to handle the subtractions */
if (0 >
TALER_amount_subtract (total,
total,
&rtotal))
{
/* underflow in history? inconceivable! Bad exchange! */
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
const struct TALER_EXCHANGE_SigningPublicKey *
TALER_EXCHANGE_get_signing_key_info (
const struct TALER_EXCHANGE_Keys *keys,
const struct TALER_ExchangePublicKeyP *exchange_pub)
{
for (unsigned int i = 0; i<keys->num_sign_keys; i++)
{
const struct TALER_EXCHANGE_SigningPublicKey *spk
= &keys->sign_keys[i];
if (0 == GNUNET_memcmp (exchange_pub,
&spk->key))
return spk;
}
return NULL;
}
/* end of exchange_api_common.c */
|