801 lines
26 KiB
C
801 lines
26 KiB
C
/*
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This file is part of TALER
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Copyright (C) 2014-2020 Taler Systems SA
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TALER is free software; you can redistribute it and/or modify it under the
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terms of the GNU General Public License as published by the Free Software
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Foundation; either version 3, or (at your option) any later version.
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TALER is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
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A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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You should have received a copy of the GNU General Public License along with
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TALER; see the file COPYING. If not, see
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<http://www.gnu.org/licenses/>
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*/
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/**
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* @file lib/exchange_api_refund.c
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* @brief Implementation of the /refund request of the exchange's HTTP API
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* @author Christian Grothoff
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*/
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#include "platform.h"
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#include <jansson.h>
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#include <microhttpd.h> /* just for HTTP status codes */
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#include <gnunet/gnunet_util_lib.h>
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#include <gnunet/gnunet_json_lib.h>
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#include <gnunet/gnunet_curl_lib.h>
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#include "taler_json_lib.h"
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#include "taler_exchange_service.h"
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#include "exchange_api_handle.h"
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#include "taler_signatures.h"
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#include "exchange_api_curl_defaults.h"
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/**
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* @brief A Refund Handle
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*/
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struct TALER_EXCHANGE_RefundHandle
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{
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/**
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* The connection to exchange this request handle will use
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*/
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struct TALER_EXCHANGE_Handle *exchange;
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/**
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* The url for this request.
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*/
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char *url;
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/**
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* Context for #TEH_curl_easy_post(). Keeps the data that must
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* persist for Curl to make the upload.
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*/
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struct TALER_CURL_PostContext ctx;
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/**
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* Handle for the request.
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*/
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struct GNUNET_CURL_Job *job;
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/**
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* Function to call with the result.
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*/
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TALER_EXCHANGE_RefundCallback cb;
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/**
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* Closure for @a cb.
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*/
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void *cb_cls;
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/**
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* Information the exchange should sign in response.
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*/
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struct TALER_RefundConfirmationPS depconf;
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};
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/**
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* Verify that the signature on the "200 OK" response
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* from the exchange is valid.
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*
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* @param[in,out] rh refund handle (refund fee added)
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* @param json json reply with the signature
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* @param[out] exchange_pub set to the exchange's public key
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* @param[out] exchange_sig set to the exchange's signature
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* @return #GNUNET_OK if the signature is valid, #GNUNET_SYSERR if not
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*/
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static int
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verify_refund_signature_ok (struct TALER_EXCHANGE_RefundHandle *rh,
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const json_t *json,
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struct TALER_ExchangePublicKeyP *exchange_pub,
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struct TALER_ExchangeSignatureP *exchange_sig)
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{
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const struct TALER_EXCHANGE_Keys *key_state;
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struct GNUNET_JSON_Specification spec[] = {
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GNUNET_JSON_spec_fixed_auto ("exchange_sig", exchange_sig),
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GNUNET_JSON_spec_fixed_auto ("exchange_pub", exchange_pub),
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GNUNET_JSON_spec_end ()
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};
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if (GNUNET_OK !=
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GNUNET_JSON_parse (json,
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spec,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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key_state = TALER_EXCHANGE_get_keys (rh->exchange);
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if (GNUNET_OK !=
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TALER_EXCHANGE_test_signing_key (key_state,
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exchange_pub))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if (GNUNET_OK !=
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GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_EXCHANGE_CONFIRM_REFUND,
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&rh->depconf,
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&exchange_sig->eddsa_signature,
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&exchange_pub->eddsa_pub))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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return GNUNET_OK;
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}
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/**
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* Verify that the information in the "409 Conflict" response
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* from the exchange is valid and indeed shows that the refund
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* amount requested is too high.
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*
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* @param[in,out] rh refund handle (refund fee added)
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* @param json json reply with the coin transaction history
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* @return #GNUNET_OK if the signature is valid, #GNUNET_SYSERR if not
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*/
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static int
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verify_conflict_history_ok (struct TALER_EXCHANGE_RefundHandle *rh,
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const json_t *json)
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{
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json_t *history;
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struct GNUNET_JSON_Specification spec[] = {
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GNUNET_JSON_spec_json ("history",
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&history),
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GNUNET_JSON_spec_end ()
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};
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size_t len;
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struct TALER_Amount dtotal;
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bool have_deposit;
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struct TALER_Amount rtotal;
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bool have_refund;
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if (GNUNET_OK !=
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GNUNET_JSON_parse (json,
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spec,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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len = json_array_size (history);
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if (0 == len)
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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have_deposit = false;
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have_refund = false;
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for (size_t off = 0; off<len; off++)
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{
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json_t *transaction;
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struct TALER_Amount amount;
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const char *type;
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struct GNUNET_JSON_Specification spec_glob[] = {
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TALER_JSON_spec_amount ("amount",
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&amount),
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GNUNET_JSON_spec_string ("type",
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&type),
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GNUNET_JSON_spec_end ()
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};
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transaction = json_array_get (history,
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off);
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if (GNUNET_OK !=
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GNUNET_JSON_parse (transaction,
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spec_glob,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if (0 == strcasecmp (type,
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"DEPOSIT"))
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{
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struct TALER_DepositRequestPS dr = {
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.purpose.size = htonl (sizeof (dr)),
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.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_DEPOSIT),
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.coin_pub = rh->depconf.coin_pub
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};
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struct TALER_CoinSpendSignatureP sig;
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struct GNUNET_JSON_Specification spec[] = {
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GNUNET_JSON_spec_fixed_auto ("coin_sig",
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&sig),
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GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
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&dr.h_contract_terms),
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GNUNET_JSON_spec_fixed_auto ("h_wire",
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&dr.h_wire),
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GNUNET_JSON_spec_fixed_auto ("h_denom_pub",
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&dr.h_denom_pub),
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TALER_JSON_spec_absolute_time_nbo ("timestamp",
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&dr.wallet_timestamp),
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TALER_JSON_spec_absolute_time_nbo ("refund_deadline",
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&dr.refund_deadline),
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TALER_JSON_spec_amount_nbo ("deposit_fee",
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&dr.deposit_fee),
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GNUNET_JSON_spec_fixed_auto ("merchant_pub",
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&dr.merchant),
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GNUNET_JSON_spec_end ()
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};
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if (GNUNET_OK !=
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GNUNET_JSON_parse (transaction,
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spec,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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TALER_amount_hton (&dr.amount_with_fee,
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&amount);
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if (GNUNET_OK !=
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GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_WALLET_COIN_DEPOSIT,
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&dr,
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&sig.eddsa_signature,
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&rh->depconf.coin_pub.eddsa_pub))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if ( (0 != GNUNET_memcmp (&rh->depconf.h_contract_terms,
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&dr.h_contract_terms)) ||
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(0 != GNUNET_memcmp (&rh->depconf.merchant,
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&dr.merchant)) )
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{
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/* deposit information is about a different merchant/contract */
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if (have_deposit)
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{
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/* this cannot really happen, but we conservatively support it anyway */
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if (GNUNET_YES !=
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TALER_amount_cmp_currency (&amount,
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&dtotal))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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GNUNET_break (0 <=
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TALER_amount_add (&dtotal,
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&dtotal,
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&amount));
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}
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else
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{
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dtotal = amount;
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have_deposit = true;
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}
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}
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else if (0 == strcasecmp (type,
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"REFUND"))
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{
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struct TALER_MerchantSignatureP sig;
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struct TALER_Amount refund_fee;
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struct TALER_Amount sig_amount;
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struct TALER_RefundRequestPS rr = {
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.purpose.size = htonl (sizeof (rr)),
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.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_REFUND),
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.coin_pub = rh->depconf.coin_pub
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};
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struct GNUNET_JSON_Specification spec[] = {
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TALER_JSON_spec_amount ("refund_fee",
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&refund_fee),
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GNUNET_JSON_spec_fixed_auto ("merchant_sig",
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&sig),
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GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
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&rr.h_contract_terms),
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GNUNET_JSON_spec_fixed_auto ("merchant_pub",
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&rr.merchant),
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GNUNET_JSON_spec_uint64 ("rtransaction_id",
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&rr.rtransaction_id), // FIXME: shouldn't this be NBO!?
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GNUNET_JSON_spec_end ()
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};
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if (GNUNET_OK !=
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GNUNET_JSON_parse (transaction,
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spec,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if (0 >
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TALER_amount_add (&sig_amount,
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&refund_fee,
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&amount))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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TALER_amount_hton (&rr.refund_amount,
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&sig_amount);
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rr.rtransaction_id = GNUNET_htonll (rr.rtransaction_id);
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if (GNUNET_OK !=
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GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MERCHANT_REFUND,
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&rr,
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&sig.eddsa_sig,
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&rr.merchant.eddsa_pub))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if ( (0 != GNUNET_memcmp (&rh->depconf.h_contract_terms,
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&rr.h_contract_terms)) ||
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(0 != GNUNET_memcmp (&rh->depconf.merchant,
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&rr.merchant)) )
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{
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/* refund is about a different merchant/contract */
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if (rr.rtransaction_id == rh->depconf.rtransaction_id)
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{
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/* Eh, this shows either a dependency failure or idempotency,
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but must not happen in a conflict reply. Fail! */
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if (have_refund)
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{
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if (GNUNET_YES !=
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TALER_amount_cmp_currency (&amount,
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&rtotal))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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GNUNET_break (0 <=
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TALER_amount_add (&rtotal,
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&rtotal,
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&amount));
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}
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else
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{
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rtotal = amount;
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have_refund = true;
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}
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}
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else
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{
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/* unexpected type, new version on server? */
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GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
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"Unexpected type `%s' in response\n",
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type);
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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}
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{
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struct TALER_Amount amount;
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TALER_amount_ntoh (&amount,
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&rh->depconf.refund_amount);
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if (have_refund)
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{
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if (0 >
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TALER_amount_add (&rtotal,
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&rtotal,
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&amount))
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{
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GNUNET_break (0);
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return GNUNET_SYSERR;
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}
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}
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else
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{
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rtotal = amount;
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}
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}
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if (-1 == TALER_amount_cmp (&dtotal,
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&rtotal))
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{
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/* dtotal < rtotal: good! */
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return GNUNET_OK;
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}
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/* this fails to prove a conflict */
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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/**
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* Verify that the information on the "412 Dependency Failed" response
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* from the exchange is valid and indeed shows that there is a refund
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* transaction ID reuse going on.
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*
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* @param[in,out] rh refund handle (refund fee added)
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* @param json json reply with the signature
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* @return #GNUNET_OK if the signature is valid, #GNUNET_SYSERR if not
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*/
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static int
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verify_failed_dependency_ok (struct TALER_EXCHANGE_RefundHandle *rh,
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const json_t *json)
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{
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json_t *h;
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json_t *e;
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struct GNUNET_JSON_Specification spec[] = {
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GNUNET_JSON_spec_json ("history", &h),
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GNUNET_JSON_spec_end ()
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};
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if (GNUNET_OK !=
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GNUNET_JSON_parse (json,
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spec,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if ( (! json_is_array (h)) ||
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(1 != json_array_size (h) ) )
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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e = json_array_get (h, 0);
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{
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struct TALER_Amount amount;
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const char *type;
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struct TALER_MerchantSignatureP sig;
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struct TALER_Amount refund_fee;
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struct TALER_RefundRequestPS rr = {
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.purpose.size = htonl (sizeof (rr)),
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.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_REFUND),
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.coin_pub = rh->depconf.coin_pub
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};
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uint64_t rtransaction_id;
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struct GNUNET_JSON_Specification spec[] = {
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TALER_JSON_spec_amount ("amount",
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&amount),
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GNUNET_JSON_spec_string ("type",
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&type),
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TALER_JSON_spec_amount ("refund_fee",
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&refund_fee),
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GNUNET_JSON_spec_fixed_auto ("merchant_sig",
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&sig),
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GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
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&rr.h_contract_terms),
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GNUNET_JSON_spec_fixed_auto ("merchant_pub",
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&rr.merchant),
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GNUNET_JSON_spec_uint64 ("rtransaction_id",
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&rtransaction_id),
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GNUNET_JSON_spec_end ()
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};
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if (GNUNET_OK !=
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GNUNET_JSON_parse (e,
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spec,
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NULL, NULL))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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rr.rtransaction_id = GNUNET_htonll (rtransaction_id);
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TALER_amount_hton (&rr.refund_amount,
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&amount);
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if (GNUNET_OK !=
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GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MERCHANT_REFUND,
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&rr,
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&sig.eddsa_sig,
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&rh->depconf.merchant.eddsa_pub))
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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if ( (rr.rtransaction_id != rh->depconf.rtransaction_id) ||
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(0 != GNUNET_memcmp (&rh->depconf.h_contract_terms,
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&rr.h_contract_terms)) ||
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(0 != GNUNET_memcmp (&rh->depconf.merchant,
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&rr.merchant)) ||
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(0 == TALER_amount_cmp_nbo (&rh->depconf.refund_amount,
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&rr.refund_amount)) )
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{
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GNUNET_break_op (0);
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return GNUNET_SYSERR;
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}
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}
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return GNUNET_OK;
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}
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/**
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* Function called when we're done processing the
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* HTTP /refund request.
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*
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* @param cls the `struct TALER_EXCHANGE_RefundHandle`
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* @param response_code HTTP response code, 0 on error
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* @param response parsed JSON result, NULL on error
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*/
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static void
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handle_refund_finished (void *cls,
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long response_code,
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const void *response)
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{
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struct TALER_EXCHANGE_RefundHandle *rh = cls;
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struct TALER_ExchangePublicKeyP exchange_pub;
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struct TALER_ExchangeSignatureP exchange_sig;
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struct TALER_ExchangePublicKeyP *ep = NULL;
|
||
struct TALER_ExchangeSignatureP *es = NULL;
|
||
const json_t *j = response;
|
||
struct TALER_EXCHANGE_HttpResponse hr = {
|
||
.reply = j,
|
||
.http_status = (unsigned int) response_code
|
||
};
|
||
|
||
rh->job = NULL;
|
||
switch (response_code)
|
||
{
|
||
case 0:
|
||
hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
|
||
break;
|
||
case MHD_HTTP_OK:
|
||
if (GNUNET_OK !=
|
||
verify_refund_signature_ok (rh,
|
||
j,
|
||
&exchange_pub,
|
||
&exchange_sig))
|
||
{
|
||
GNUNET_break_op (0);
|
||
hr.http_status = 0;
|
||
hr.ec = TALER_EC_EXCHANGE_REFUND_INVALID_SIGNATURE_BY_EXCHANGE;
|
||
}
|
||
else
|
||
{
|
||
ep = &exchange_pub;
|
||
es = &exchange_sig;
|
||
}
|
||
break;
|
||
case MHD_HTTP_BAD_REQUEST:
|
||
/* This should never happen, either us or the exchange is buggy
|
||
(or API version conflict); also can happen if the currency
|
||
differs (which we should obviously never support).
|
||
Just pass JSON reply to the application */
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
case MHD_HTTP_FORBIDDEN:
|
||
/* Nothing really to verify, exchange says one of the signatures is
|
||
invalid; as we checked them, this should never happen, we
|
||
should pass the JSON reply to the application */
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
case MHD_HTTP_NOT_FOUND:
|
||
/* Nothing really to verify, this should never
|
||
happen, we should pass the JSON reply to the application */
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
case MHD_HTTP_CONFLICT:
|
||
/* Requested total refunds exceed deposited amount */
|
||
if (GNUNET_OK !=
|
||
verify_conflict_history_ok (rh,
|
||
j))
|
||
{
|
||
GNUNET_break (0);
|
||
hr.http_status = 0;
|
||
hr.ec = TALER_EC_EXCHANGE_REFUND_INVALID_FAILURE_PROOF_BY_EXCHANGE;
|
||
hr.hint = "conflict information provided by exchange is invalid";
|
||
break;
|
||
}
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
case MHD_HTTP_GONE:
|
||
/* Kind of normal: the money was already sent to the merchant
|
||
(it was too late for the refund). */
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
case MHD_HTTP_PRECONDITION_FAILED:
|
||
if (GNUNET_OK !=
|
||
verify_failed_dependency_ok (rh,
|
||
j))
|
||
{
|
||
GNUNET_break (0);
|
||
hr.http_status = 0;
|
||
hr.ec = TALER_EC_EXCHANGE_REFUND_INVALID_FAILURE_PROOF_BY_EXCHANGE;
|
||
hr.hint = "failed precondition proof returned by exchange is invalid";
|
||
break;
|
||
}
|
||
/* Two different refund requests were made about the same deposit, but
|
||
carrying identical refund transaction ids. */
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
case MHD_HTTP_INTERNAL_SERVER_ERROR:
|
||
/* Server had an internal issue; we should retry, but this API
|
||
leaves this to the application */
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
break;
|
||
default:
|
||
/* unexpected response code */
|
||
GNUNET_break_op (0);
|
||
hr.ec = TALER_JSON_get_error_code (j);
|
||
hr.hint = TALER_JSON_get_error_hint (j);
|
||
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
|
||
"Unexpected response code %u/%d\n",
|
||
(unsigned int) response_code,
|
||
hr.ec);
|
||
break;
|
||
}
|
||
rh->cb (rh->cb_cls,
|
||
&hr,
|
||
ep,
|
||
es);
|
||
TALER_EXCHANGE_refund_cancel (rh);
|
||
}
|
||
|
||
|
||
/**
|
||
* Submit a refund request to the exchange and get the exchange's
|
||
* response. This API is used by a merchant. Note that
|
||
* while we return the response verbatim to the caller for further
|
||
* processing, we do already verify that the response is well-formed
|
||
* (i.e. that signatures included in the response are all valid). If
|
||
* the exchange's reply is not well-formed, we return an HTTP status code
|
||
* of zero to @a cb.
|
||
*
|
||
* The @a exchange must be ready to operate (i.e. have
|
||
* finished processing the /keys reply). If this check fails, we do
|
||
* NOT initiate the transaction with the exchange and instead return NULL.
|
||
*
|
||
* @param exchange the exchange handle; the exchange must be ready to operate
|
||
* @param amount the amount to be refunded; must be larger than the refund fee
|
||
* (as that fee is still being subtracted), and smaller than the amount
|
||
* (with deposit fee) of the original deposit contribution of this coin
|
||
* @param h_contract_terms hash of the contact of the merchant with the customer that is being refunded
|
||
* @param coin_pub coin’s public key of the coin from the original deposit operation
|
||
* @param rtransaction_id transaction id for the transaction between merchant and customer (of refunding operation);
|
||
* this is needed as we may first do a partial refund and later a full refund. If both
|
||
* refunds are also over the same amount, we need the @a rtransaction_id to make the disjoint
|
||
* refund requests different (as requests are idempotent and otherwise the 2nd refund might not work).
|
||
* @param merchant_priv the private key of the merchant, used to generate signature for refund request
|
||
* @param cb the callback to call when a reply for this request is available
|
||
* @param cb_cls closure for the above callback
|
||
* @return a handle for this request; NULL if the inputs are invalid (i.e.
|
||
* signatures fail to verify). In this case, the callback is not called.
|
||
*/
|
||
struct TALER_EXCHANGE_RefundHandle *
|
||
TALER_EXCHANGE_refund (struct TALER_EXCHANGE_Handle *exchange,
|
||
const struct TALER_Amount *amount,
|
||
const struct GNUNET_HashCode *h_contract_terms,
|
||
const struct TALER_CoinSpendPublicKeyP *coin_pub,
|
||
uint64_t rtransaction_id,
|
||
const struct TALER_MerchantPrivateKeyP *merchant_priv,
|
||
TALER_EXCHANGE_RefundCallback cb,
|
||
void *cb_cls)
|
||
{
|
||
struct TALER_RefundRequestPS rr = {
|
||
.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_REFUND),
|
||
.purpose.size = htonl (sizeof (rr)),
|
||
.h_contract_terms = *h_contract_terms,
|
||
.rtransaction_id = GNUNET_htonll (rtransaction_id),
|
||
.coin_pub = *coin_pub
|
||
};
|
||
struct TALER_MerchantSignatureP merchant_sig;
|
||
struct TALER_EXCHANGE_RefundHandle *rh;
|
||
struct GNUNET_CURL_Context *ctx;
|
||
json_t *refund_obj;
|
||
CURL *eh;
|
||
char arg_str[sizeof (struct TALER_CoinSpendPublicKeyP) * 2 + 32];
|
||
|
||
GNUNET_assert (GNUNET_YES ==
|
||
TEAH_handle_is_ready (exchange));
|
||
GNUNET_CRYPTO_eddsa_key_get_public (&merchant_priv->eddsa_priv,
|
||
&rr.merchant.eddsa_pub);
|
||
TALER_amount_hton (&rr.refund_amount,
|
||
amount);
|
||
GNUNET_CRYPTO_eddsa_sign (&merchant_priv->eddsa_priv,
|
||
&rr,
|
||
&merchant_sig.eddsa_sig);
|
||
|
||
|
||
{
|
||
char pub_str[sizeof (struct TALER_CoinSpendPublicKeyP) * 2];
|
||
char *end;
|
||
|
||
end = GNUNET_STRINGS_data_to_string (coin_pub,
|
||
sizeof (struct
|
||
TALER_CoinSpendPublicKeyP),
|
||
pub_str,
|
||
sizeof (pub_str));
|
||
*end = '\0';
|
||
GNUNET_snprintf (arg_str,
|
||
sizeof (arg_str),
|
||
"/coins/%s/refund",
|
||
pub_str);
|
||
}
|
||
refund_obj = json_pack ("{s:o," /* amount */
|
||
" s:o," /* h_contract_terms */
|
||
" s:I," /* rtransaction id */
|
||
" s:o, s:o}", /* merchant_pub, merchant_sig */
|
||
"refund_amount", TALER_JSON_from_amount (amount),
|
||
"h_contract_terms", GNUNET_JSON_from_data_auto (
|
||
h_contract_terms),
|
||
"rtransaction_id", (json_int_t) rtransaction_id,
|
||
"merchant_pub", GNUNET_JSON_from_data_auto (
|
||
&rr.merchant),
|
||
"merchant_sig", GNUNET_JSON_from_data_auto (
|
||
&merchant_sig)
|
||
);
|
||
if (NULL == refund_obj)
|
||
{
|
||
GNUNET_break (0);
|
||
return NULL;
|
||
}
|
||
|
||
rh = GNUNET_new (struct TALER_EXCHANGE_RefundHandle);
|
||
rh->exchange = exchange;
|
||
rh->cb = cb;
|
||
rh->cb_cls = cb_cls;
|
||
rh->url = TEAH_path_to_url (exchange,
|
||
arg_str);
|
||
rh->depconf.purpose.size = htonl (sizeof (struct TALER_RefundConfirmationPS));
|
||
rh->depconf.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_REFUND);
|
||
rh->depconf.h_contract_terms = *h_contract_terms;
|
||
rh->depconf.coin_pub = *coin_pub;
|
||
rh->depconf.merchant = rr.merchant;
|
||
rh->depconf.rtransaction_id = GNUNET_htonll (rtransaction_id);
|
||
TALER_amount_hton (&rh->depconf.refund_amount,
|
||
amount);
|
||
|
||
eh = TALER_EXCHANGE_curl_easy_get_ (rh->url);
|
||
if ( (NULL == eh) ||
|
||
(GNUNET_OK !=
|
||
TALER_curl_easy_post (&rh->ctx,
|
||
eh,
|
||
refund_obj)) )
|
||
{
|
||
GNUNET_break (0);
|
||
if (NULL != eh)
|
||
curl_easy_cleanup (eh);
|
||
json_decref (refund_obj);
|
||
GNUNET_free (rh->url);
|
||
GNUNET_free (rh);
|
||
return NULL;
|
||
}
|
||
json_decref (refund_obj);
|
||
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
|
||
"URL for refund: `%s'\n",
|
||
rh->url);
|
||
ctx = TEAH_handle_to_context (exchange);
|
||
rh->job = GNUNET_CURL_job_add2 (ctx,
|
||
eh,
|
||
rh->ctx.headers,
|
||
&handle_refund_finished,
|
||
rh);
|
||
return rh;
|
||
}
|
||
|
||
|
||
/**
|
||
* Cancel a refund permission request. This function cannot be used
|
||
* on a request handle if a response is already served for it.
|
||
*
|
||
* @param refund the refund permission request handle
|
||
*/
|
||
void
|
||
TALER_EXCHANGE_refund_cancel (struct TALER_EXCHANGE_RefundHandle *refund)
|
||
{
|
||
if (NULL != refund->job)
|
||
{
|
||
GNUNET_CURL_job_cancel (refund->job);
|
||
refund->job = NULL;
|
||
}
|
||
GNUNET_free (refund->url);
|
||
TALER_curl_easy_post_finished (&refund->ctx);
|
||
GNUNET_free (refund);
|
||
}
|
||
|
||
|
||
/* end of exchange_api_refund.c */
|