/*
This file is part of TALER
Copyright (C) 2014-2018 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
*/
/**
* @file taler-exchange-httpd_transfers_get.c
* @brief Handle wire transfer(s) GET requests
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include
#include
#include "taler_signatures.h"
#include "taler-exchange-httpd_keys.h"
#include "taler-exchange-httpd_transfers_get.h"
#include "taler-exchange-httpd_responses.h"
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
/**
* Information about one of the transactions that was
* aggregated, to be returned in the /transfers response.
*/
struct AggregatedDepositDetail
{
/**
* We keep deposit details in a DLL.
*/
struct AggregatedDepositDetail *next;
/**
* We keep deposit details in a DLL.
*/
struct AggregatedDepositDetail *prev;
/**
* Hash of the contract terms.
*/
struct GNUNET_HashCode h_contract_terms;
/**
* Coin's public key of the deposited coin.
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
/**
* Total value of the coin in the deposit.
*/
struct TALER_Amount deposit_value;
/**
* Fees charged by the exchange for the deposit of this coin.
*/
struct TALER_Amount deposit_fee;
};
/**
* A merchant asked for transaction details about a wire transfer.
* Provide them. Generates the 200 reply.
*
* @param connection connection to the client
* @param total total amount that was transferred
* @param merchant_pub public key of the merchant
* @param h_wire destination account
* @param wire_fee wire fee that was charged
* @param exec_time execution time of the wire transfer
* @param wdd_head linked list with details about the combined deposits
* @return MHD result code
*/
static MHD_RESULT
reply_transfer_details (struct MHD_Connection *connection,
const struct TALER_Amount *total,
const struct TALER_MerchantPublicKeyP *merchant_pub,
const struct GNUNET_HashCode *h_wire,
const struct TALER_Amount *wire_fee,
struct GNUNET_TIME_Absolute exec_time,
const struct AggregatedDepositDetail *wdd_head)
{
json_t *deposits;
struct TALER_WireDepositDetailP dd;
struct GNUNET_HashContext *hash_context;
struct TALER_WireDepositDataPS wdp;
struct TALER_ExchangePublicKeyP pub;
struct TALER_ExchangeSignatureP sig;
GNUNET_TIME_round_abs (&exec_time);
deposits = json_array ();
if (NULL == deposits)
{
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_JSON_ALLOCATION_FAILURE,
"json_array() failed");
}
hash_context = GNUNET_CRYPTO_hash_context_start ();
for (const struct AggregatedDepositDetail *wdd_pos = wdd_head;
NULL != wdd_pos;
wdd_pos = wdd_pos->next)
{
dd.h_contract_terms = wdd_pos->h_contract_terms;
dd.execution_time = GNUNET_TIME_absolute_hton (exec_time);
dd.coin_pub = wdd_pos->coin_pub;
TALER_amount_hton (&dd.deposit_value,
&wdd_pos->deposit_value);
TALER_amount_hton (&dd.deposit_fee,
&wdd_pos->deposit_fee);
GNUNET_CRYPTO_hash_context_read (hash_context,
&dd,
sizeof (struct TALER_WireDepositDetailP));
if (0 !=
json_array_append_new (deposits,
json_pack ("{s:o, s:o, s:o, s:o}",
"h_contract_terms",
GNUNET_JSON_from_data_auto (
&wdd_pos->h_contract_terms),
"coin_pub",
GNUNET_JSON_from_data_auto (
&wdd_pos->coin_pub),
"deposit_value",
TALER_JSON_from_amount (
&wdd_pos->deposit_value),
"deposit_fee",
TALER_JSON_from_amount (
&wdd_pos->deposit_fee))))
{
json_decref (deposits);
GNUNET_CRYPTO_hash_context_abort (hash_context);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_JSON_ALLOCATION_FAILURE,
"json_array_append_new() failed");
}
}
wdp.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE_DEPOSIT);
wdp.purpose.size = htonl (sizeof (struct TALER_WireDepositDataPS));
TALER_amount_hton (&wdp.total,
total);
TALER_amount_hton (&wdp.wire_fee,
wire_fee);
wdp.merchant_pub = *merchant_pub;
wdp.h_wire = *h_wire;
GNUNET_CRYPTO_hash_context_finish (hash_context,
&wdp.h_details);
{
enum TALER_ErrorCode ec;
if (TALER_EC_NONE !=
(ec = TEH_keys_exchange_sign (&wdp,
&pub,
&sig)))
{
json_decref (deposits);
return TALER_MHD_reply_with_ec (connection,
ec,
NULL);
}
}
return TALER_MHD_reply_json_pack (connection,
MHD_HTTP_OK,
"{s:o, s:o, s:o, s:o, s:o, s:o, s:o, s:o}",
"total", TALER_JSON_from_amount (total),
"wire_fee", TALER_JSON_from_amount (
wire_fee),
"merchant_pub",
GNUNET_JSON_from_data_auto (
merchant_pub),
"h_wire", GNUNET_JSON_from_data_auto (
h_wire),
"execution_time",
GNUNET_JSON_from_time_abs (exec_time),
"deposits", deposits,
"exchange_sig",
GNUNET_JSON_from_data_auto (&sig),
"exchange_pub",
GNUNET_JSON_from_data_auto (&pub));
}
/**
* Closure for #handle_transaction_data.
*/
struct WtidTransactionContext
{
/**
* Identifier of the wire transfer to track.
*/
struct TALER_WireTransferIdentifierRawP wtid;
/**
* Total amount of the wire transfer, as calculated by
* summing up the individual amounts. To be rounded down
* to calculate the real transfer amount at the end.
* Only valid if @e is_valid is #GNUNET_YES.
*/
struct TALER_Amount total;
/**
* Public key of the merchant, only valid if @e is_valid
* is #GNUNET_YES.
*/
struct TALER_MerchantPublicKeyP merchant_pub;
/**
* Hash of the wire details of the merchant (identical for all
* deposits), only valid if @e is_valid is #GNUNET_YES.
*/
struct GNUNET_HashCode h_wire;
/**
* Wire fee applicable at @e exec_time.
*/
struct TALER_Amount wire_fee;
/**
* Execution time of the wire transfer
*/
struct GNUNET_TIME_Absolute exec_time;
/**
* Head of DLL with deposit details for transfers GET response.
*/
struct AggregatedDepositDetail *wdd_head;
/**
* Tail of DLL with deposit details for transfers GET response.
*/
struct AggregatedDepositDetail *wdd_tail;
/**
* Which method was used to wire the funds?
*/
char *wire_method;
/**
* JSON array with details about the individual deposits.
*/
json_t *deposits;
/**
* Initially #GNUNET_NO, if we found no deposits so far. Set to
* #GNUNET_YES if we got transaction data, and the database replies
* remained consistent with respect to @e merchant_pub and @e h_wire
* (as they should). Set to #GNUNET_SYSERR if we encountered an
* internal error.
*/
int is_valid;
};
/**
* Function called with the results of the lookup of the individual deposits
* that were aggregated for the given wire transfer.
*
* @param cls our context for transmission
* @param rowid which row in the DB is the information from (for diagnostics), ignored
* @param merchant_pub public key of the merchant (should be same for all callbacks with the same @e cls)
* @param h_wire hash of wire transfer details of the merchant (should be same for all callbacks with the same @e cls)
* @param wire where the funds were sent
* @param exec_time execution time of the wire transfer (should be same for all callbacks with the same @e cls)
* @param h_contract_terms which proposal was this payment about
* @param denom_pub denomination public key of the @a coin_pub (ignored)
* @param coin_pub which public key was this payment about
* @param deposit_value amount contributed by this coin in total
* @param deposit_fee deposit fee charged by exchange for this coin
*/
static void
handle_deposit_data (void *cls,
uint64_t rowid,
const struct TALER_MerchantPublicKeyP *merchant_pub,
const struct GNUNET_HashCode *h_wire,
const json_t *wire,
struct GNUNET_TIME_Absolute exec_time,
const struct GNUNET_HashCode *h_contract_terms,
const struct TALER_DenominationPublicKey *denom_pub,
const struct TALER_CoinSpendPublicKeyP *coin_pub,
const struct TALER_Amount *deposit_value,
const struct TALER_Amount *deposit_fee)
{
struct WtidTransactionContext *ctx = cls;
char *wire_method;
(void) rowid;
(void) denom_pub;
if (GNUNET_SYSERR == ctx->is_valid)
return;
if (NULL == (wire_method = TALER_JSON_wire_to_method (wire)))
{
GNUNET_break (0);
ctx->is_valid = GNUNET_SYSERR;
return;
}
if (GNUNET_NO == ctx->is_valid)
{
/* First one we encounter, setup general information in 'ctx' */
ctx->merchant_pub = *merchant_pub;
ctx->h_wire = *h_wire;
ctx->exec_time = exec_time;
ctx->wire_method = wire_method; /* captures the reference */
ctx->is_valid = GNUNET_YES;
if (0 >
TALER_amount_subtract (&ctx->total,
deposit_value,
deposit_fee))
{
GNUNET_break (0);
ctx->is_valid = GNUNET_SYSERR;
return;
}
}
else
{
struct TALER_Amount delta;
/* Subsequent data, check general information matches that in 'ctx';
(it should, otherwise the deposits should not have been aggregated) */
if ( (0 != GNUNET_memcmp (&ctx->merchant_pub,
merchant_pub)) ||
(0 != strcmp (wire_method,
ctx->wire_method)) ||
(0 != GNUNET_memcmp (&ctx->h_wire,
h_wire)) )
{
GNUNET_break (0);
ctx->is_valid = GNUNET_SYSERR;
GNUNET_free (wire_method);
return;
}
GNUNET_free (wire_method);
if (0 >
TALER_amount_subtract (&delta,
deposit_value,
deposit_fee))
{
GNUNET_break (0);
ctx->is_valid = GNUNET_SYSERR;
return;
}
if (0 >
TALER_amount_add (&ctx->total,
&ctx->total,
&delta))
{
GNUNET_break (0);
ctx->is_valid = GNUNET_SYSERR;
return;
}
}
{
struct AggregatedDepositDetail *wdd;
wdd = GNUNET_new (struct AggregatedDepositDetail);
wdd->deposit_value = *deposit_value;
wdd->deposit_fee = *deposit_fee;
wdd->h_contract_terms = *h_contract_terms;
wdd->coin_pub = *coin_pub;
GNUNET_CONTAINER_DLL_insert (ctx->wdd_head,
ctx->wdd_tail,
wdd);
}
}
/**
* Free data structure reachable from @a ctx, but not @a ctx itself.
*
* @param ctx context to free
*/
static void
free_ctx (struct WtidTransactionContext *ctx)
{
struct AggregatedDepositDetail *wdd;
while (NULL != (wdd = ctx->wdd_head))
{
GNUNET_CONTAINER_DLL_remove (ctx->wdd_head,
ctx->wdd_tail,
wdd);
GNUNET_free (wdd);
}
GNUNET_free (ctx->wire_method);
ctx->wire_method = NULL;
}
/**
* Execute a "/transfers" GET operation. Returns the deposit details of the
* deposits that were aggregated to create the given wire transfer.
*
* 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
* @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
get_transfer_deposits (void *cls,
struct MHD_Connection *connection,
struct TALER_EXCHANGEDB_Session *session,
MHD_RESULT *mhd_ret)
{
struct WtidTransactionContext *ctx = cls;
enum GNUNET_DB_QueryStatus qs;
struct GNUNET_TIME_Absolute wire_fee_start_date;
struct GNUNET_TIME_Absolute wire_fee_end_date;
struct TALER_MasterSignatureP wire_fee_master_sig;
struct TALER_Amount closing_fee;
/* resetting to NULL/0 in case transaction was repeated after
serialization failure */
free_ctx (ctx);
qs = TEH_plugin->lookup_wire_transfer (TEH_plugin->cls,
session,
&ctx->wtid,
&handle_deposit_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_GENERIC_DB_FETCH_FAILED,
"wire transfer");
}
return qs;
}
if (GNUNET_SYSERR == ctx->is_valid)
{
GNUNET_break (0);
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_INVARIANT_FAILURE,
"wire history malformed");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (GNUNET_NO == ctx->is_valid)
{
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_EXCHANGE_TRANSFERS_GET_WTID_NOT_FOUND,
NULL);
return GNUNET_DB_STATUS_HARD_ERROR;
}
qs = TEH_plugin->get_wire_fee (TEH_plugin->cls,
session,
ctx->wire_method,
ctx->exec_time,
&wire_fee_start_date,
&wire_fee_end_date,
&ctx->wire_fee,
&closing_fee,
&wire_fee_master_sig);
if (0 >= qs)
{
if ( (GNUNET_DB_STATUS_HARD_ERROR == qs) ||
(GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs) )
{
GNUNET_break (0);
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_TRANSFERS_GET_WIRE_FEE_NOT_FOUND,
NULL);
}
return qs;
}
if (0 >
TALER_amount_subtract (&ctx->total,
&ctx->total,
&ctx->wire_fee))
{
GNUNET_break (0);
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_TRANSFERS_GET_WIRE_FEE_INCONSISTENT,
NULL);
return GNUNET_DB_STATUS_HARD_ERROR;
}
return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT;
}
/**
* Handle a GET "/transfers/$WTID" request.
*
* @param rh context of the handler
* @param connection the MHD connection to handle
* @param args array of additional options (length: 1, just the wtid)
* @return MHD result code
*/
MHD_RESULT
TEH_handler_transfers_get (const struct TEH_RequestHandler *rh,
struct MHD_Connection *connection,
const char *const args[1])
{
struct WtidTransactionContext ctx;
MHD_RESULT mhd_ret;
(void) rh;
memset (&ctx,
0,
sizeof (ctx));
if (GNUNET_OK !=
GNUNET_STRINGS_string_to_data (args[0],
strlen (args[0]),
&ctx.wtid,
sizeof (ctx.wtid)))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_TRANSFERS_GET_WTID_MALFORMED,
args[0]);
}
if (GNUNET_OK !=
TEH_DB_run_transaction (connection,
"run transfers GET",
&mhd_ret,
&get_transfer_deposits,
&ctx))
{
free_ctx (&ctx);
return mhd_ret;
}
mhd_ret = reply_transfer_details (connection,
&ctx.total,
&ctx.merchant_pub,
&ctx.h_wire,
&ctx.wire_fee,
ctx.exec_time,
ctx.wdd_head);
free_ctx (&ctx);
return mhd_ret;
}
/* end of taler-exchange-httpd_transfers_get.c */