/*
This file is part of TALER
Copyright (C) 2014-2017 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
*/
/**
* @file taler-exchange-httpd_track_transaction.c
* @brief Handle wire transfer tracking-related requests
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include
#include
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
#include "taler_signatures.h"
#include "taler-exchange-httpd_keystate.h"
#include "taler-exchange-httpd_track_transaction.h"
#include "taler-exchange-httpd_responses.h"
/**
* A merchant asked for details about a deposit, but
* we did not execute the deposit yet. Generate a 202 reply.
*
* @param connection connection to the client
* @param planned_exec_time planned execution time
* @return MHD result code
*/
static int
reply_transfer_pending (struct MHD_Connection *connection,
struct GNUNET_TIME_Absolute planned_exec_time)
{
return TALER_MHD_reply_json_pack (connection,
MHD_HTTP_ACCEPTED,
"{s:o}",
"execution_time",
GNUNET_JSON_from_time_abs (
planned_exec_time));
}
/**
* A merchant asked for details about a deposit. Provide
* them. Generates the 200 reply.
*
* @param connection connection to the client
* @param h_contract_terms hash of the contract
* @param h_wire hash of wire account details
* @param coin_pub public key of the coin
* @param coin_contribution how much did the coin we asked about
* contribute to the total transfer value? (deposit value minus fee)
* @param wtid raw wire transfer identifier
* @param exec_time execution time of the wire transfer
* @return MHD result code
*/
static int
reply_track_transaction (struct MHD_Connection *connection,
const struct GNUNET_HashCode *h_contract_terms,
const struct GNUNET_HashCode *h_wire,
const struct TALER_CoinSpendPublicKeyP *coin_pub,
const struct TALER_Amount *coin_contribution,
const struct TALER_WireTransferIdentifierRawP *wtid,
struct GNUNET_TIME_Absolute exec_time)
{
struct TALER_ConfirmWirePS cw;
struct TALER_ExchangePublicKeyP pub;
struct TALER_ExchangeSignatureP sig;
cw.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE);
cw.purpose.size = htonl (sizeof (struct TALER_ConfirmWirePS));
cw.h_wire = *h_wire;
cw.h_contract_terms = *h_contract_terms;
cw.wtid = *wtid;
cw.coin_pub = *coin_pub;
cw.execution_time = GNUNET_TIME_absolute_hton (exec_time);
TALER_amount_hton (&cw.coin_contribution,
coin_contribution);
if (GNUNET_OK !=
TEH_KS_sign (&cw.purpose,
&pub,
&sig))
{
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_BAD_CONFIGURATION,
"no keys");
}
return TALER_MHD_reply_json_pack (connection,
MHD_HTTP_OK,
"{s:o, s:o, s:o, s:o, s:o}",
"wtid", GNUNET_JSON_from_data_auto (
wtid),
"execution_time",
GNUNET_JSON_from_time_abs (exec_time),
"coin_contribution",
TALER_JSON_from_amount (
coin_contribution),
"exchange_sig",
GNUNET_JSON_from_data_auto (&sig),
"exchange_pub",
GNUNET_JSON_from_data_auto (&pub));
}
/**
* Closure for #handle_wtid_data.
*/
struct DepositWtidContext
{
/**
* Deposit details.
*/
const struct TALER_DepositTrackPS *tps;
/**
* Public key of the merchant.
*/
const struct TALER_MerchantPublicKeyP *merchant_pub;
/**
* Set by #handle_wtid data to the wire transfer ID.
*/
struct TALER_WireTransferIdentifierRawP wtid;
/**
* Set by #handle_wtid data to the coin's contribution to the wire transfer.
*/
struct TALER_Amount coin_contribution;
/**
* Set by #handle_wtid data to the fee charged to the coin.
*/
struct TALER_Amount coin_fee;
/**
* Set by #handle_wtid data to the wire transfer execution time.
*/
struct GNUNET_TIME_Absolute execution_time;
/**
* Set by #handle_wtid to the coin contribution to the transaction
* (that is, @e coin_contribution minus @e coin_fee).
*/
struct TALER_Amount coin_delta;
/**
* Set to #GNUNET_YES by #handle_wtid if the wire transfer is still pending
* (and the above were not set).
* Set to #GNUNET_SYSERR if there was a serious error.
*/
int pending;
};
/**
* Function called with the results of the lookup of the
* wire transfer identifier information.
*
* @param cls our context for transmission
* @param wtid raw wire transfer identifier, NULL
* if the transaction was not yet done
* @param coin_contribution how much did the coin we asked about
* contribute to the total transfer value? (deposit value including fee)
* @param coin_fee how much did the exchange charge for the deposit fee
* @param execution_time when was the transaction done, or
* when we expect it to be done (if @a wtid was NULL);
* #GNUNET_TIME_UNIT_FOREVER_ABS if the /deposit is unknown
* to the exchange
*/
static void
handle_wtid_data (void *cls,
const struct TALER_WireTransferIdentifierRawP *wtid,
const struct TALER_Amount *coin_contribution,
const struct TALER_Amount *coin_fee,
struct GNUNET_TIME_Absolute execution_time)
{
struct DepositWtidContext *ctx = cls;
if (NULL == wtid)
{
ctx->pending = GNUNET_YES;
ctx->execution_time = execution_time;
return;
}
if (GNUNET_SYSERR ==
TALER_amount_subtract (&ctx->coin_delta,
coin_contribution,
coin_fee))
{
GNUNET_break (0);
ctx->pending = GNUNET_SYSERR;
return;
}
ctx->wtid = *wtid;
ctx->execution_time = execution_time;
ctx->coin_contribution = *coin_contribution;
ctx->coin_fee = *coin_fee;
}
/**
* Execute a "/track/transaction". Returns the transfer information
* associated with the given deposit.
*
* 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 closure of type `struct DepositWtidContext *`
* @param connection MHD request which triggered the transaction
* @param session database session to use
* @param[out] mhd_ret set to MHD response status for @a connection,
* if transaction failed (!)
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
track_transaction_transaction (void *cls,
struct MHD_Connection *connection,
struct TALER_EXCHANGEDB_Session *session,
int *mhd_ret)
{
struct DepositWtidContext *ctx = cls;
enum GNUNET_DB_QueryStatus qs;
qs = TEH_plugin->wire_lookup_deposit_wtid (TEH_plugin->cls,
session,
&ctx->tps->h_contract_terms,
&ctx->tps->h_wire,
&ctx->tps->coin_pub,
ctx->merchant_pub,
&handle_wtid_data,
ctx);
if (0 > qs)
{
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_TRACK_TRANSACTION_DB_FETCH_FAILED,
"failed to fetch transaction data");
}
return qs;
}
if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
{
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_TRACK_TRANSACTION_NOT_FOUND,
"transaction unknown");
return GNUNET_DB_STATUS_HARD_ERROR;
}
return qs;
}
/**
* Check the merchant signature, and if it is valid,
* return the wire transfer identifier.
*
* @param connection the MHD connection to handle
* @param tps signed request to execute
* @param merchant_pub public key from the merchant
* @param merchant_sig signature from the merchant (to be checked)
* @return MHD result code
*/
static int
check_and_handle_track_transaction_request (struct MHD_Connection *connection,
const struct
TALER_DepositTrackPS *tps,
const struct
TALER_MerchantPublicKeyP *
merchant_pub,
const struct
TALER_MerchantSignatureP *
merchant_sig)
{
struct DepositWtidContext ctx;
int mhd_ret;
if (GNUNET_OK !=
GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MERCHANT_TRACK_TRANSACTION,
&tps->purpose,
&merchant_sig->eddsa_sig,
&merchant_pub->eddsa_pub))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_TRACK_TRANSACTION_MERCHANT_SIGNATURE_INVALID,
"merchant_sig");
}
ctx.pending = GNUNET_NO;
ctx.tps = tps;
ctx.merchant_pub = merchant_pub;
if (GNUNET_OK !=
TEH_DB_run_transaction (connection,
"handle track transaction",
&mhd_ret,
&track_transaction_transaction,
&ctx))
return mhd_ret;
if (GNUNET_YES == ctx.pending)
return reply_transfer_pending (connection,
ctx.execution_time);
if (GNUNET_SYSERR == ctx.pending)
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_TRACK_TRANSACTION_DB_FEE_INCONSISTENT,
"fees are inconsistent");
return reply_track_transaction (connection,
&tps->h_contract_terms,
&tps->h_wire,
&tps->coin_pub,
&ctx.coin_delta,
&ctx.wtid,
ctx.execution_time);
}
/**
* Handle a "/track/transaction" 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_TRACKING_handler_track_transaction (struct TEH_RequestHandler *rh,
struct MHD_Connection *connection,
void **connection_cls,
const char *upload_data,
size_t *upload_data_size)
{
int res;
json_t *json;
struct TALER_DepositTrackPS tps;
struct TALER_MerchantSignatureP merchant_sig;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("h_wire", &tps.h_wire),
GNUNET_JSON_spec_fixed_auto ("h_contract_terms", &tps.h_contract_terms),
GNUNET_JSON_spec_fixed_auto ("coin_pub", &tps.coin_pub),
GNUNET_JSON_spec_fixed_auto ("merchant_pub", &tps.merchant),
GNUNET_JSON_spec_fixed_auto ("merchant_sig", &merchant_sig),
GNUNET_JSON_spec_end ()
};
(void) rh;
res = TALER_MHD_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 = TALER_MHD_parse_json_data (connection,
json,
spec);
if (GNUNET_OK != res)
{
json_decref (json);
return (GNUNET_NO == res) ? MHD_YES : MHD_NO;
}
tps.purpose.size = htonl (sizeof (struct TALER_DepositTrackPS));
tps.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_TRACK_TRANSACTION);
res = check_and_handle_track_transaction_request (connection,
&tps,
&tps.merchant,
&merchant_sig);
GNUNET_JSON_parse_free (spec);
json_decref (json);
return res;
}
/* end of taler-exchange-httpd_track_transaction.c */