first skeleton of /deposit-confirmation API implementation; not yet complete, cannot work as-is, see FIXMEs

1 files changed, 226 insertions, 0 deletions

diff --git a/src/auditor/taler-auditor-httpd_deposit-confirmation.c b/src/auditor/taler-auditor-httpd_deposit-confirmation.c
new file mode 100644
index 000000000..88ec9c967
--- /dev/null
+++ b/src/auditor/taler-auditor-httpd_deposit-confirmation.c
@@ -0,0 +1,226 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2014-2018 Inria and GNUnet e.V.
+
+  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-auditor-httpd_deposit-confirmation.c
+ * @brief Handle /deposit-confirmation requests; parses the POST and JSON and
+ *        verifies the coin signature before handing things off
+ *        to the database.
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <gnunet/gnunet_util_lib.h>
+#include <gnunet/gnunet_json_lib.h>
+#include <jansson.h>
+#include <microhttpd.h>
+#include <pthread.h>
+#include "taler_json_lib.h"
+#include "taler-auditor-httpd.h"
+#include "taler-auditor-httpd_db.h"
+#include "taler-auditor-httpd_deposit-confirmation.h"
+#include "taler-auditor-httpd_parsing.h"
+#include "taler-auditor-httpd_responses.h"
+
+
+/**
+ * Send confirmation of deposit-confirmation success to client.
+ *
+ * @param connection connection to the client
+ * @return MHD result code
+ */
+static int
+reply_deposit_confirmation_success (struct MHD_Connection *connection)
+{
+  return TAH_RESPONSE_reply_json_pack (connection,
+                                       MHD_HTTP_OK,
+                                       "{s:s}",
+                                       "status", "DEPOSIT_CONFIRMATION_OK");
+}
+
+
+/**
+ * Execute database transaction for /deposit-confirmation.  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 DepositConfirmation *`
+ * @param connection MHD request context
+ * @param session database session and transaction to use -- FIXME: needed?
+ * @param[out] mhd_ret set to MHD status on error
+ * @return transaction status
+ */
+static enum GNUNET_DB_QueryStatus
+deposit_confirmation_transaction (void *cls,
+                                  struct MHD_Connection *connection,
+                                  struct TALER_AUDITORDB_Session *session,
+                                  int *mhd_ret)
+{
+  const struct TALER_AUDITORDB_DepositConfirmation *dc = cls;
+  enum GNUNET_DB_QueryStatus qs;
+
+  qs = TAH_plugin->insert_deposit_confirmation (TAH_plugin->cls,
+                                                session,
+                                                dc);
+  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+  {
+    TALER_LOG_WARNING ("Failed to store /deposit-confirmation information in database\n");
+    *mhd_ret = TAH_RESPONSE_reply_internal_db_error (connection,
+						     TALER_EC_DEPOSIT_CONFIRMATION_STORE_DB_ERROR);
+  }
+  return qs;
+}
+
+
+/**
+ * We have parsed the JSON information about the deposit, do some
+ * basic sanity checks (especially that the signature on the coin is
+ * valid, and that this type of coin exists) and then execute the
+ * deposit.
+ *
+ * @param connection the MHD connection to handle
+ * @param dc information about the deposit confirmation
+ * @return MHD result code
+ */
+static int
+verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
+                                         const struct TALER_AUDITORDB_DepositConfirmation *dc)
+{
+  struct TALER_ExchangeSigningKeyValidityPS skv;
+  struct TALER_DepositConfirmationPS dcs;
+  int mhd_ret;
+
+  /* check signatures */
+  dcs.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT);
+  dcs.purpose.size = htonl (sizeof (struct TALER_DepositConfirmationPS));
+  dcs.h_contract_terms = dc->h_contract_terms;
+  dcs.h_wire = dc->h_wire;
+  dcs.timestamp = GNUNET_TIME_absolute_hton (dc->timestamp);
+  dcs.refund_deadline = GNUNET_TIME_absolute_hton (dc->refund_deadline);
+  TALER_amount_hton (&dcs.amount_without_fee,
+                     &dc->amount_without_fee);
+  dcs.coin_pub = dc->coin_pub;
+  dcs.merchant = dc->merchant;
+  if (GNUNET_OK !=
+      GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT,
+                                  &dcs.purpose,
+                                  &dc->exchange_sig.eddsa_signature,
+                                  &dc->exchange_pub.eddsa_pub))
+  {
+    TALER_LOG_WARNING ("Invalid signature on /deposit-confirmation request\n");
+    return TAH_RESPONSE_reply_signature_invalid (connection,
+						 TALER_EC_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
+                                                 "exchange_sig");
+  }
+  /* TODO: we should probably cache these, no need to verify the
+     exchange_sig's every time (wastes CPU) */
+  skv.purpose.purpose = htonl (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY);
+  skv.purpose.size = htonl (sizeof (struct TALER_ExchangeSigningKeyValidityPS));
+  skv.master_public_key = dc->master_public_key;
+  skv.start; // FIXME
+  skv.expire; // FIXME
+  skv.end; // FIXME
+  skv.signkey_pub = dc->exchange_pub;
+  if (GNUNET_OK !=
+      GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY,
+                                  &skv.purpose,
+                                  &dc->master_sig.eddsa_signature,
+                                  &dc->master_public_key.eddsa_pub))
+  {
+    TALER_LOG_WARNING ("Invalid signature on /deposit-confirmation request\n");
+    return TAH_RESPONSE_reply_signature_invalid (connection,
+						 TALER_EC_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
+                                                 "master_sig");
+  }
+
+  /* execute transaction */
+  if (GNUNET_OK !=
+      TAH_DB_run_transaction (connection,
+                              "store deposit confirmation",
+			      &mhd_ret,
+			      &deposit_confirmation_transaction,
+			      (void *) dc))
+    return mhd_ret;
+  return reply_deposit_confirmation_success (connection);
+}
+
+
+/**
+ * Handle a "/deposit-confirmation" request.  Parses the JSON, and, if
+ * successful, passes the JSON data to #verify_and_execute_deposit_confirmation()
+ * to further check the details of the operation specified.  If
+ * everything checks out, this will ultimately lead to the "/deposit-confirmation"
+ * being stored in the database.
+ *
+ * @param rh context of the handler
+ * @param connection the MHD connection to handle
+ * @param[in,out] connection_cls the connection's closure (can be updated)
+ * @param upload_data upload data
+ * @param[in,out] upload_data_size number of bytes (left) in @a upload_data
+ * @return MHD result code
+  */
+int
+TAH_DEPOSIT_CONFIRMATION_handler (struct TAH_RequestHandler *rh,
+                                  struct MHD_Connection *connection,
+                                  void **connection_cls,
+                                  const char *upload_data,
+                                  size_t *upload_data_size)
+{
+  json_t *json;
+  int res;
+  struct TALER_AUDITORDB_DepositConfirmation dc;
+  struct GNUNET_JSON_Specification spec[] = {
+    GNUNET_JSON_spec_fixed_auto ("h_contract_terms", &dc.h_contract_terms),
+    GNUNET_JSON_spec_fixed_auto ("h_wire", &dc.h_wire),
+    GNUNET_JSON_spec_absolute_time ("timestamp", &dc.timestamp),
+    GNUNET_JSON_spec_absolute_time ("refund_deadline", &dc.refund_deadline),
+    TALER_JSON_spec_amount ("amount_without_fee", &dc.amount_without_fee),
+    GNUNET_JSON_spec_fixed_auto ("coin_pub", &dc.coin_pub),
+    GNUNET_JSON_spec_fixed_auto ("merchant_pub", &dc.merchant),
+    GNUNET_JSON_spec_fixed_auto ("exchange_sig",  &dc.exchange_sig),
+    GNUNET_JSON_spec_fixed_auto ("exchange_pub",  &dc.exchange_pub),
+    GNUNET_JSON_spec_fixed_auto ("master_sig",  &dc.master_sig),
+    GNUNET_JSON_spec_fixed_auto ("master_public_key",  &dc.master_public_key),
+    GNUNET_JSON_spec_end ()
+  };
+
+  res = TAH_PARSE_post_json (connection,
+                             connection_cls,
+                             upload_data,
+                             upload_data_size,
+                             &json);
+  if (GNUNET_SYSERR == res)
+    return MHD_NO;
+  if ( (GNUNET_NO == res) ||
+       (NULL == json) )
+    return MHD_YES;
+  res = TAH_PARSE_json_data (connection,
+                             json,
+                             spec);
+  json_decref (json);
+  if (GNUNET_SYSERR == res)
+    return MHD_NO; /* hard failure */
+  if (GNUNET_NO == res)
+    return MHD_YES; /* failure */
+  res = verify_and_execute_deposit_confirmation (connection,
+                                                 &dc);
+  GNUNET_JSON_parse_free (spec);
+  return res;
+}
+
+
+/* end of taler-auditor-httpd_deposit-confirmation.c */