summaryrefslogtreecommitdiff
path: root/src/exchange/taler-exchange-httpd_reserves_history.c
blob: 2c936244780fb992439265b5c05eef9cc9dc8b3b (plain)
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
/*
  This file is part of TALER
  Copyright (C) 2014-2022 Taler Systems SA

  TALER is free software; you can redistribute it and/or modify it under the
  terms of the GNU Affero 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 Affero General Public License for more details.

  You should have received a copy of the GNU Affero General Public License along with
  TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
*/
/**
 * @file taler-exchange-httpd_reserves_history.c
 * @brief Handle /reserves/$RESERVE_PUB/history requests
 * @author Florian Dold
 * @author Benedikt Mueller
 * @author Christian Grothoff
 */
#include "platform.h"
#include <gnunet/gnunet_util_lib.h>
#include <jansson.h>
#include "taler_mhd_lib.h"
#include "taler_json_lib.h"
#include "taler_dbevents.h"
#include "taler-exchange-httpd_keys.h"
#include "taler-exchange-httpd_reserves_history.h"
#include "taler-exchange-httpd_responses.h"


/**
 * How far do we allow a client's time to be off when
 * checking the request timestamp?
 */
#define TIMESTAMP_TOLERANCE \
  GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)


/**
 * Closure for #reserve_history_transaction.
 */
struct ReserveHistoryContext
{
  /**
   * Public key of the reserve the inquiry is about.
   */
  const struct TALER_ReservePublicKeyP *reserve_pub;

  /**
   * Timestamp of the request.
   */
  struct GNUNET_TIME_Timestamp timestamp;

  /**
   * Client signature approving the request.
   */
  struct TALER_ReserveSignatureP reserve_sig;

  /**
   * History of the reserve, set in the callback.
   */
  struct TALER_EXCHANGEDB_ReserveHistory *rh;

  /**
   * Global fees applying to the request.
   */
  const struct TEH_GlobalFee *gf;

  /**
   * Current reserve balance.
   */
  struct TALER_Amount balance;
};


/**
 * Send reserve history to client.
 *
 * @param connection connection to the client
 * @param rhc reserve history to return
 * @return MHD result code
 */
static MHD_RESULT
reply_reserve_history_success (struct MHD_Connection *connection,
                               const struct ReserveHistoryContext *rhc)
{
  const struct TALER_EXCHANGEDB_ReserveHistory *rh = rhc->rh;
  json_t *json_history;

  json_history = TEH_RESPONSE_compile_reserve_history (rh);
  if (NULL == json_history)
    return TALER_MHD_reply_with_error (connection,
                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
                                       TALER_EC_GENERIC_JSON_ALLOCATION_FAILURE,
                                       NULL);
  /* FIXME: should set explicit cache control headers
     for this response to enable caching! */
  return TALER_MHD_REPLY_JSON_PACK (
    connection,
    MHD_HTTP_OK,
    TALER_JSON_pack_amount ("balance",
                            &rhc->balance),
    GNUNET_JSON_pack_array_steal ("history",
                                  json_history));
}


/**
 * Function implementing /reserves/$RID/history transaction.  Given the public
 * key of a reserve, return the associated transaction history.  Runs the
 * transaction logic; IF it returns a non-error code, the transaction logic
 * MUST NOT queue a MHD response.  IF it returns an hard error, the
 * transaction logic MUST queue a MHD response and set @a mhd_ret.  IF it
 * returns the soft error code, the function MAY be called again to retry and
 * MUST not queue a MHD response.
 *
 * @param cls a `struct ReserveHistoryContext *`
 * @param connection MHD request which triggered the transaction
 * @param[out] mhd_ret set to MHD response status for @a connection,
 *             if transaction failed (!); unused
 * @return transaction status
 */
static enum GNUNET_DB_QueryStatus
reserve_history_transaction (void *cls,
                             struct MHD_Connection *connection,
                             MHD_RESULT *mhd_ret)
{
  struct ReserveHistoryContext *rsc = cls;
  enum GNUNET_DB_QueryStatus qs;

  if (! TALER_amount_is_zero (&rsc->gf->fees.history))
  {
    bool balance_ok = false;
    bool idempotent = true;

    qs = TEH_plugin->insert_history_request (TEH_plugin->cls,
                                             rsc->reserve_pub,
                                             &rsc->reserve_sig,
                                             rsc->timestamp,
                                             &rsc->gf->fees.history,
                                             &balance_ok,
                                             &idempotent);
    if (GNUNET_DB_STATUS_HARD_ERROR == qs)
    {
      GNUNET_break (0);
      *mhd_ret
        = TALER_MHD_reply_with_error (connection,
                                      MHD_HTTP_INTERNAL_SERVER_ERROR,
                                      TALER_EC_GENERIC_DB_FETCH_FAILED,
                                      "get_reserve_history");
    }
    if (qs <= 0)
    {
      GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
      return qs;
    }
    if (! balance_ok)
    {
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_CONFLICT,
                                         TALER_EC_EXCHANGE_WITHDRAW_HISTORY_ERROR_INSUFFICIENT_FUNDS,
                                         NULL);
    }
    if (idempotent)
    {
      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                  "Idempotent /reserves/history request observed. Is caching working?\n");
    }
  }
  qs = TEH_plugin->get_reserve_history (TEH_plugin->cls,
                                        rsc->reserve_pub,
                                        &rsc->balance,
                                        &rsc->rh);
  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
  {
    GNUNET_break (0);
    *mhd_ret
      = TALER_MHD_reply_with_error (connection,
                                    MHD_HTTP_INTERNAL_SERVER_ERROR,
                                    TALER_EC_GENERIC_DB_FETCH_FAILED,
                                    "get_reserve_history");
  }
  return qs;
}


MHD_RESULT
TEH_handler_reserves_history (struct TEH_RequestContext *rc,
                              const struct TALER_ReservePublicKeyP *reserve_pub,
                              const json_t *root)
{
  struct ReserveHistoryContext rsc;
  MHD_RESULT mhd_ret;
  struct GNUNET_JSON_Specification spec[] = {
    GNUNET_JSON_spec_timestamp ("request_timestamp",
                                &rsc.timestamp),
    GNUNET_JSON_spec_fixed_auto ("reserve_sig",
                                 &rsc.reserve_sig),
    GNUNET_JSON_spec_end ()
  };
  struct GNUNET_TIME_Timestamp now;

  rsc.reserve_pub = reserve_pub;
  {
    enum GNUNET_GenericReturnValue res;

    res = TALER_MHD_parse_json_data (rc->connection,
                                     root,
                                     spec);
    if (GNUNET_SYSERR == res)
    {
      GNUNET_break (0);
      return MHD_NO; /* hard failure */
    }
    if (GNUNET_NO == res)
    {
      GNUNET_break_op (0);
      return MHD_YES; /* failure */
    }
  }
  now = GNUNET_TIME_timestamp_get ();
  if (! GNUNET_TIME_absolute_approx_eq (now.abs_time,
                                        rsc.timestamp.abs_time,
                                        TIMESTAMP_TOLERANCE))
  {
    GNUNET_break_op (0);
    return TALER_MHD_reply_with_error (rc->connection,
                                       MHD_HTTP_BAD_REQUEST,
                                       TALER_EC_EXCHANGE_GENERIC_CLOCK_SKEW,
                                       NULL);
  }
  {
    struct TEH_KeyStateHandle *keys;

    keys = TEH_keys_get_state ();
    if (NULL == keys)
    {
      GNUNET_break (0);
      GNUNET_JSON_parse_free (spec);
      return TALER_MHD_reply_with_error (rc->connection,
                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
                                         TALER_EC_EXCHANGE_GENERIC_KEYS_MISSING,
                                         NULL);
    }
    rsc.gf = TEH_keys_global_fee_by_time (keys,
                                          rsc.timestamp);
  }
  if (NULL == rsc.gf)
  {
    GNUNET_break (0);
    return TALER_MHD_reply_with_error (rc->connection,
                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
                                       TALER_EC_EXCHANGE_GENERIC_BAD_CONFIGURATION,
                                       NULL);
  }
  if (GNUNET_OK !=
      TALER_wallet_reserve_history_verify (rsc.timestamp,
                                           &rsc.gf->fees.history,
                                           reserve_pub,
                                           &rsc.reserve_sig))
  {
    GNUNET_break_op (0);
    return TALER_MHD_reply_with_error (rc->connection,
                                       MHD_HTTP_FORBIDDEN,
                                       TALER_EC_EXCHANGE_RESERVES_HISTORY_BAD_SIGNATURE,
                                       NULL);
  }
  rsc.rh = NULL;
  if (GNUNET_OK !=
      TEH_DB_run_transaction (rc->connection,
                              "get reserve history",
                              TEH_MT_REQUEST_OTHER,
                              &mhd_ret,
                              &reserve_history_transaction,
                              &rsc))
  {
    return mhd_ret;
  }
  if (NULL == rsc.rh)
  {
    return TALER_MHD_reply_with_error (rc->connection,
                                       MHD_HTTP_NOT_FOUND,
                                       TALER_EC_EXCHANGE_RESERVES_STATUS_UNKNOWN,
                                       NULL);
  }
  mhd_ret = reply_reserve_history_success (rc->connection,
                                           &rsc);
  TEH_plugin->free_reserve_history (TEH_plugin->cls,
                                    rsc.rh);
  return mhd_ret;
}


/* end of taler-exchange-httpd_reserves_history.c */