integrating refresh payback with standard payback, almost done

src/exchange/Makefile.am

@@ -51,7 +51,6 @@ taler_exchange_httpd_SOURCES = \
   taler-exchange-httpd_payback.c taler-exchange-httpd_payback.h \
   taler-exchange-httpd_refresh_link.c taler-exchange-httpd_refresh_link.h \
   taler-exchange-httpd_refresh_melt.c taler-exchange-httpd_refresh_melt.h \
-  taler-exchange-httpd_refresh_payback.c taler-exchange-httpd_refresh_payback.h \
   taler-exchange-httpd_refresh_reveal.c taler-exchange-httpd_refresh_reveal.h \
   taler-exchange-httpd_refund.c taler-exchange-httpd_refund.h \
   taler-exchange-httpd_reserve_status.c taler-exchange-httpd_reserve_status.h \

src/exchange/taler-exchange-httpd.c

@@ -36,7 +36,6 @@
 #include "taler-exchange-httpd_payback.h"
 #include "taler-exchange-httpd_refresh_link.h"
 #include "taler-exchange-httpd_refresh_melt.h"
-#include "taler-exchange-httpd_refresh_payback.h"
 #include "taler-exchange-httpd_refresh_reveal.h"
 #include "taler-exchange-httpd_track_transfer.h"
 #include "taler-exchange-httpd_track_transaction.h"
@@ -318,13 +317,6 @@ handle_mhd_request (void *cls,
         "Only GET is allowed", 0,
         &TEH_MHD_handler_send_json_pack_error, MHD_HTTP_METHOD_NOT_ALLOWED },
 
-      { "/refresh/payback", MHD_HTTP_METHOD_POST, "application/json",
-        NULL, 0,
-        &TEH_REFRESH_handler_refresh_payback, MHD_HTTP_OK },
-      { "/refresh/payback", NULL, "text/plain",
-        "Only POST is allowed", 0,
-        &TEH_MHD_handler_send_json_pack_error, MHD_HTTP_METHOD_NOT_ALLOWED },
-
       { "/track/transfer", MHD_HTTP_METHOD_GET, "application/json",
         NULL, 0,
         &TEH_TRACKING_handler_track_transfer, MHD_HTTP_OK },

src/exchange/taler-exchange-httpd_payback.c

@@ -54,6 +54,54 @@ reply_payback_unknown (struct MHD_Connection *connection,
 }
 
 
+/**
+ * A wallet asked for /payback, return the successful response.
+ *
+ * @param connection connection to the client
+ * @param coin_pub coin for which we are processing the payback request
+ * @param old_coin_pub public key of the old coin that will receive the payback
+ * @param amount the amount we will wire back
+ * @param timestamp when did the exchange receive the /payback request
+ * @return MHD result code
+ */
+static int
+reply_payback_refresh_success (struct MHD_Connection *connection,
+                               const struct TALER_CoinSpendPublicKeyP *coin_pub,
+                               const struct TALER_CoinSpendPublicKeyP *old_coin_pub,
+                               const struct TALER_Amount *amount,
+                               struct GNUNET_TIME_Absolute timestamp)
+{
+  struct TALER_PaybackRefreshConfirmationPS pc;
+  struct TALER_ExchangePublicKeyP pub;
+  struct TALER_ExchangeSignatureP sig;
+
+  pc.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_PAYBACK_REFRESH);
+  pc.purpose.size = htonl (sizeof (struct TALER_PaybackRefreshConfirmationPS));
+  pc.timestamp = GNUNET_TIME_absolute_hton (timestamp);
+  TALER_amount_hton (&pc.payback_amount,
+                     amount);
+  pc.coin_pub = *coin_pub;
+  pc.old_coin_pub = *old_coin_pub;
+  if (GNUNET_OK !=
+      TEH_KS_sign (&pc.purpose,
+                   &pub,
+                   &sig))
+  {
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
+  return TEH_RESPONSE_reply_json_pack (connection,
+                                       MHD_HTTP_OK,
+                                       "{s:o, s:o, s:o, s:o, s:o}",
+                                       "old_coin_pub", GNUNET_JSON_from_data_auto (old_coin_pub),
+                                       "timestamp", GNUNET_JSON_from_time_abs (timestamp),
+                                       "amount", TALER_JSON_from_amount (amount),
+                                       "exchange_sig", GNUNET_JSON_from_data_auto (&sig),
+                                       "exchange_pub", GNUNET_JSON_from_data_auto (&pub));
+}
+
+
 /**
  * A wallet asked for /payback, return the successful response.
  *
@@ -132,12 +180,21 @@ struct PaybackContext
    */
   const struct TALER_CoinSpendSignatureP *coin_sig;
 
+  union
+  {
     /**
      * Set by #payback_transaction() to the reserve that will
-   * receive the payback.
+     * receive the payback, if #refreshed is #GNUNET_NO.
      */
     struct TALER_ReservePublicKeyP reserve_pub;
 
+    /**
+     * Set by #payback_transaction() to the old coin that will
+     * receive the payback, if #refreshed is #GNUNET_YES.
+     */
+    struct TALER_CoinSpendPublicKeyP old_coin_pub;
+  } target;
+
   /**
    * Set by #payback_transaction() to the amount that will be paid back
    */
@@ -149,6 +206,11 @@ struct PaybackContext
    */
   struct GNUNET_TIME_Absolute now;
 
+  /**
+   * #GNUNET_YES if the client claims the coin originated from a refresh.
+   */
+  int refreshed;
+
 };
 
 
@@ -183,10 +245,15 @@ payback_transaction (void *cls,
 
   /* Check whether a payback is allowed, and if so, to which
      reserve / account the money should go */
-  qs = TEH_plugin->get_reserve_by_h_blind (TEH_plugin->cls,
+  if (pc->refreshed)
+  {
+    GNUNET_assert (0); // FIXME: not implemented in DB!
+#if 0
+    qs = TEH_plugin->get_old_coin_by_h_blind (TEH_plugin->cls,
                                               session,
                                               &pc->h_blind,
-                                           &pc->reserve_pub);
+                                              &pc->target.old_coin_pub);
+#endif
     if (0 > qs)
     {
       if (GNUNET_DB_STATUS_HARD_ERROR == qs)
@@ -197,6 +264,24 @@ payback_transaction (void *cls,
       }
       return qs;
     }
+  }
+  else
+  {
+    qs = TEH_plugin->get_reserve_by_h_blind (TEH_plugin->cls,
+                                             session,
+                                             &pc->h_blind,
+                                             &pc->target.reserve_pub);
+    if (0 > qs)
+    {
+      if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+      {
+        GNUNET_break (0);
+        *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection,
+                                                         TALER_EC_PAYBACK_DB_FETCH_FAILED);
+      }
+      return qs;
+    }
+  }
   if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
   {
     GNUNET_break_op (0);
@@ -266,15 +351,29 @@ payback_transaction (void *cls,
   (void) GNUNET_TIME_round_abs (&pc->now);
 
   /* add coin to list of wire transfers for payback */
-  qs = TEH_plugin->insert_payback_request (TEH_plugin->cls,
+  if (pc->refreshed)
+  {
+    qs = TEH_plugin->insert_payback_refresh_request (TEH_plugin->cls,
                                                      session,
-                                           &pc->reserve_pub,
                                                      pc->coin,
                                                      pc->coin_sig,
                                                      pc->coin_bks,
                                                      &pc->amount,
                                                      &pc->h_blind,
                                                      pc->now);
+  }
+  else
+  {
+    qs = TEH_plugin->insert_payback_request (TEH_plugin->cls,
+                                             session,
+                                             &pc->target.reserve_pub,
+                                             pc->coin,
+                                             pc->coin_sig,
+                                             pc->coin_bks,
+                                             &pc->amount,
+                                             &pc->h_blind,
+                                             pc->now);
+  }
   if (0 > qs)
   {
     if (GNUNET_DB_STATUS_HARD_ERROR == qs)
@@ -300,13 +399,15 @@ payback_transaction (void *cls,
  * @param coin information about the coin
  * @param coin_bks blinding data of the coin (to be checked)
  * @param coin_sig signature of the coin
+ * @param refreshed #GNUNET_YES if the coin was refreshed
  * @return MHD result code
  */
 static int
 verify_and_execute_payback (struct MHD_Connection *connection,
                             const struct TALER_CoinPublicInfo *coin,
                             const struct TALER_DenominationBlindingKeyP *coin_bks,
-                            const struct TALER_CoinSpendSignatureP *coin_sig)
+                            const struct TALER_CoinSpendSignatureP *coin_sig,
+                            int refreshed)
 {
   struct PaybackContext pc;
   struct TEH_KS_StateHandle *key_state;
@@ -413,6 +514,7 @@ verify_and_execute_payback (struct MHD_Connection *connection,
   pc.coin_sig = coin_sig;
   pc.coin_bks = coin_bks;
   pc.coin = coin;
+  pc.refreshed = refreshed;
   {
     int mhd_ret;
 
@@ -424,9 +526,15 @@ verify_and_execute_payback (struct MHD_Connection *connection,
                                 &pc))
       return mhd_ret;
   }
-  return reply_payback_success (connection,
+  return (refreshed)
+    ? reply_payback_refresh_success (connection,
                                      &coin->coin_pub,
-				&pc.reserve_pub,
+                                     &pc.target.old_coin_pub,
+                                     &pc.amount,
+                                     pc.now)
+    : reply_payback_success (connection,
+                             &coin->coin_pub,
+                             &pc.target.reserve_pub,
                              &pc.amount,
                              pc.now);
 }
@@ -458,6 +566,7 @@ TEH_PAYBACK_handler_payback (struct TEH_RequestHandler *rh,
   struct TALER_CoinPublicInfo coin;
   struct TALER_DenominationBlindingKeyP coin_bks;
   struct TALER_CoinSpendSignatureP coin_sig;
+  int refreshed = GNUNET_NO;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_fixed_auto ("denom_pub_hash",
                                  &coin.denom_pub_hash),
@@ -469,6 +578,9 @@ TEH_PAYBACK_handler_payback (struct TEH_RequestHandler *rh,
                                  &coin_bks),
     GNUNET_JSON_spec_fixed_auto ("coin_sig",
                                  &coin_sig),
+    GNUNET_JSON_spec_mark_optional
+    (GNUNET_JSON_spec_boolean ("refreshed",
+                               &refreshed)),
     GNUNET_JSON_spec_end ()
   };
 
@@ -492,7 +604,8 @@ TEH_PAYBACK_handler_payback (struct TEH_RequestHandler *rh,
   res = verify_and_execute_payback (connection,
                                     &coin,
                                     &coin_bks,
-                                    &coin_sig);
+                                    &coin_sig,
+                                    refreshed);
   GNUNET_JSON_parse_free (spec);
   return res;
 }

src/exchange/taler-exchange-httpd_refresh_payback.c

@@ -1,57 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2014-2019 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_refresh_link.c
- * @brief Handle /refresh/link requests
- * @author Florian Dold
- * @author Benedikt Mueller
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include <gnunet/gnunet_util_lib.h>
-#include <jansson.h>
-#include <microhttpd.h>
-#include "taler-exchange-httpd_parsing.h"
-#include "taler-exchange-httpd_mhd.h"
-#include "taler-exchange-httpd_refresh_payback.h"
-#include "taler-exchange-httpd_responses.h"
-#include "taler-exchange-httpd_keystate.h"
-
-
-/**
- * Handle a "/refresh/payback" request.  Parses the request into the JSON
- * components and then processes the request.
- *
- * @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
-TEH_REFRESH_handler_refresh_payback (struct TEH_RequestHandler *rh,
-                                     struct MHD_Connection *connection,
-                                     void **connection_cls,
-                                     const char *upload_data,
-                                     size_t *upload_data_size)
-{
-  GNUNET_break (0);
-  return MHD_NO;
-}
-
-
-/* end of taler-exchange-httpd_refresh_payback.c */

src/exchange/taler-exchange-httpd_refresh_payback.h

@@ -1,49 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2014-2019 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_refresh_payback.h
- * @brief Handle /refresh/payback requests
- * @author Florian Dold
- * @author Christian Grothoff
- */
-#ifndef TALER_EXCHANGE_HTTPD_REFRESH_PAYBACK_H
-#define TALER_EXCHANGE_HTTPD_REFRESH_PAYBACK_H
-
-#include <gnunet/gnunet_util_lib.h>
-#include <microhttpd.h>
-#include "taler-exchange-httpd.h"
-
-
-/**
- * Handle a "/refresh/payback" request.  Parses the request into the JSON
- * components and then processes the request.
- *
- * @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
-TEH_REFRESH_handler_refresh_payback (struct TEH_RequestHandler *rh,
-                                     struct MHD_Connection *connection,
-                                     void **connection_cls,
-                                     const char *upload_data,
-                                     size_t *upload_data_size);
-
-
-#endif