/*
This file is part of TALER
Copyright (C) 2014-2023 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_deposits_get.c
* @brief Handle wire deposit tracking-related requests
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include
#include
#include "taler_dbevents.h"
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
#include "taler_signatures.h"
#include "taler-exchange-httpd_keys.h"
#include "taler-exchange-httpd_deposits_get.h"
#include "taler-exchange-httpd_responses.h"
/**
* Closure for #handle_wtid_data.
*/
struct DepositWtidContext
{
/**
* Kept in a DLL.
*/
struct DepositWtidContext *next;
/**
* Kept in a DLL.
*/
struct DepositWtidContext *prev;
/**
* Context for the request we are processing.
*/
struct TEH_RequestContext *rc;
/**
* Subscription for the database event we are waiting for.
*/
struct GNUNET_DB_EventHandler *eh;
/**
* Hash over the proposal data of the contract for which this deposit is made.
*/
struct TALER_PrivateContractHashP h_contract_terms;
/**
* Hash over the wiring information of the merchant.
*/
struct TALER_MerchantWireHashP h_wire;
/**
* The Merchant's public key. The deposit inquiry request is to be
* signed by the corresponding private key (using EdDSA).
*/
struct TALER_MerchantPublicKeyP merchant;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange.
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
/**
* Set by #handle_wtid data to the wire transfer ID.
*/
struct TALER_WireTransferIdentifierRawP wtid;
/**
* Signature by the merchant.
*/
struct TALER_MerchantSignatureP merchant_sig;
/**
* 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_Timestamp execution_time;
/**
* Timeout of the request, for long-polling.
*/
struct GNUNET_TIME_Absolute timeout;
/**
* 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;
/**
* KYC status information for the receiving account.
*/
struct TALER_EXCHANGEDB_KycStatus kyc;
/**
* AML status information for the receiving account.
*/
enum TALER_AmlDecisionState aml_decision;
/**
* 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.
*/
enum GNUNET_GenericReturnValue pending;
/**
* #GNUNET_YES if we were suspended, #GNUNET_SYSERR
* if we were woken up due to shutdown.
*/
enum GNUNET_GenericReturnValue suspended;
};
/**
* Head of DLL of suspended requests.
*/
static struct DepositWtidContext *dwc_head;
/**
* Tail of DLL of suspended requests.
*/
static struct DepositWtidContext *dwc_tail;
void
TEH_deposits_get_cleanup ()
{
struct DepositWtidContext *n;
for (struct DepositWtidContext *ctx = dwc_head;
NULL != ctx;
ctx = n)
{
n = ctx->next;
GNUNET_assert (GNUNET_YES == ctx->suspended);
ctx->suspended = GNUNET_SYSERR;
MHD_resume_connection (ctx->rc->connection);
GNUNET_CONTAINER_DLL_remove (dwc_head,
dwc_tail,
ctx);
}
}
/**
* A merchant asked for details about a deposit. Provide
* them. Generates the 200 reply.
*
* @param connection connection to the client
* @param ctx details to respond with
* @return MHD result code
*/
static MHD_RESULT
reply_deposit_details (
struct MHD_Connection *connection,
const struct DepositWtidContext *ctx)
{
struct TALER_ExchangePublicKeyP pub;
struct TALER_ExchangeSignatureP sig;
enum TALER_ErrorCode ec;
if (TALER_EC_NONE !=
(ec = TALER_exchange_online_confirm_wire_sign (
&TEH_keys_exchange_sign_,
&ctx->h_wire,
&ctx->h_contract_terms,
&ctx->wtid,
&ctx->coin_pub,
ctx->execution_time,
&ctx->coin_delta,
&pub,
&sig)))
{
GNUNET_break (0);
return TALER_MHD_reply_with_ec (connection,
ec,
NULL);
}
return TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_OK,
GNUNET_JSON_pack_data_auto ("wtid",
&ctx->wtid),
GNUNET_JSON_pack_timestamp ("execution_time",
ctx->execution_time),
TALER_JSON_pack_amount ("coin_contribution",
&ctx->coin_delta),
GNUNET_JSON_pack_data_auto ("exchange_sig",
&sig),
GNUNET_JSON_pack_data_auto ("exchange_pub",
&pub));
}
/**
* Execute a "deposits" GET. 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[out] mhd_ret set to MHD response status for @a connection,
* if transaction failed (!)
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
deposits_get_transaction (void *cls,
struct MHD_Connection *connection,
MHD_RESULT *mhd_ret)
{
struct DepositWtidContext *ctx = cls;
enum GNUNET_DB_QueryStatus qs;
bool pending;
struct TALER_Amount fee;
qs = TEH_plugin->lookup_transfer_by_deposit (TEH_plugin->cls,
&ctx->h_contract_terms,
&ctx->h_wire,
&ctx->coin_pub,
&ctx->merchant,
&pending,
&ctx->wtid,
&ctx->execution_time,
&ctx->coin_contribution,
&fee,
&ctx->kyc,
&ctx->aml_decision);
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,
NULL);
}
return qs;
}
if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
{
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_EXCHANGE_DEPOSITS_GET_NOT_FOUND,
NULL);
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (0 >
TALER_amount_subtract (&ctx->coin_delta,
&ctx->coin_contribution,
&fee))
{
GNUNET_break (0);
ctx->pending = GNUNET_SYSERR;
return qs;
}
ctx->pending = (pending) ? GNUNET_YES : GNUNET_NO;
return qs;
}
/**
* Function called on events received from Postgres.
* Wakes up long pollers.
*
* @param cls the `struct DepositWtidContext *`
* @param extra additional event data provided
* @param extra_size number of bytes in @a extra
*/
static void
db_event_cb (void *cls,
const void *extra,
size_t extra_size)
{
struct DepositWtidContext *ctx = cls;
struct GNUNET_AsyncScopeSave old_scope;
(void) extra;
(void) extra_size;
if (GNUNET_YES != ctx->suspended)
return; /* might get multiple wake-up events */
GNUNET_CONTAINER_DLL_remove (dwc_head,
dwc_tail,
ctx);
GNUNET_async_scope_enter (&ctx->rc->async_scope_id,
&old_scope);
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Resuming request handling\n");
TEH_check_invariants ();
ctx->suspended = GNUNET_NO;
MHD_resume_connection (ctx->rc->connection);
TALER_MHD_daemon_trigger ();
TEH_check_invariants ();
GNUNET_async_scope_restore (&old_scope);
}
/**
* Lookup and return the wire transfer identifier.
*
* @param ctx context of the signed request to execute
* @return MHD result code
*/
static MHD_RESULT
handle_track_transaction_request (
struct DepositWtidContext *ctx)
{
struct MHD_Connection *connection = ctx->rc->connection;
if ( (GNUNET_TIME_absolute_is_future (ctx->timeout)) &&
(NULL == ctx->eh) )
{
struct TALER_CoinDepositEventP rep = {
.header.size = htons (sizeof (rep)),
.header.type = htons (TALER_DBEVENT_EXCHANGE_DEPOSIT_STATUS_CHANGED),
.merchant_pub = ctx->merchant
};
ctx->eh = TEH_plugin->event_listen (
TEH_plugin->cls,
GNUNET_TIME_absolute_get_remaining (ctx->timeout),
&rep.header,
&db_event_cb,
ctx);
GNUNET_break (NULL != ctx->eh);
}
{
MHD_RESULT mhd_ret;
if (GNUNET_OK !=
TEH_DB_run_transaction (connection,
"handle deposits GET",
TEH_MT_REQUEST_OTHER,
&mhd_ret,
&deposits_get_transaction,
ctx))
return mhd_ret;
}
if (GNUNET_SYSERR == ctx->pending)
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_INVARIANT_FAILURE,
"wire fees exceed aggregate in database");
if (GNUNET_YES == ctx->pending)
{
if ( (GNUNET_TIME_absolute_is_future (ctx->timeout)) &&
(GNUNET_NO == ctx->suspended) )
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Suspending request handling\n");
GNUNET_CONTAINER_DLL_insert (dwc_head,
dwc_tail,
ctx);
ctx->suspended = GNUNET_YES;
MHD_suspend_connection (connection);
return MHD_YES;
}
return TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_ACCEPTED,
GNUNET_JSON_pack_allow_null (
(0 == ctx->kyc.requirement_row)
? GNUNET_JSON_pack_string ("requirement_row",
NULL)
: GNUNET_JSON_pack_uint64 ("requirement_row",
ctx->kyc.requirement_row)),
GNUNET_JSON_pack_uint64 ("aml_decision",
(uint32_t) ctx->aml_decision),
GNUNET_JSON_pack_bool ("kyc_ok",
ctx->kyc.ok),
GNUNET_JSON_pack_timestamp ("execution_time",
ctx->execution_time));
}
return reply_deposit_details (connection,
ctx);
}
/**
* Function called to clean up a context.
*
* @param rc request context with data to clean up
*/
static void
dwc_cleaner (struct TEH_RequestContext *rc)
{
struct DepositWtidContext *ctx = rc->rh_ctx;
GNUNET_assert (GNUNET_NO == ctx->suspended);
if (NULL != ctx->eh)
{
TEH_plugin->event_listen_cancel (TEH_plugin->cls,
ctx->eh);
ctx->eh = NULL;
}
GNUNET_free (ctx);
}
MHD_RESULT
TEH_handler_deposits_get (struct TEH_RequestContext *rc,
const char *const args[4])
{
struct DepositWtidContext *ctx = rc->rh_ctx;
if (NULL == ctx)
{
ctx = GNUNET_new (struct DepositWtidContext);
ctx->rc = rc;
rc->rh_ctx = ctx;
rc->rh_cleaner = &dwc_cleaner;
if (GNUNET_OK !=
GNUNET_STRINGS_string_to_data (args[0],
strlen (args[0]),
&ctx->h_wire,
sizeof (ctx->h_wire)))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (rc->connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_DEPOSITS_GET_INVALID_H_WIRE,
args[0]);
}
if (GNUNET_OK !=
GNUNET_STRINGS_string_to_data (args[1],
strlen (args[1]),
&ctx->merchant,
sizeof (ctx->merchant)))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (rc->connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_DEPOSITS_GET_INVALID_MERCHANT_PUB,
args[1]);
}
if (GNUNET_OK !=
GNUNET_STRINGS_string_to_data (args[2],
strlen (args[2]),
&ctx->h_contract_terms,
sizeof (ctx->h_contract_terms)))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (rc->connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_DEPOSITS_GET_INVALID_H_CONTRACT_TERMS,
args[2]);
}
if (GNUNET_OK !=
GNUNET_STRINGS_string_to_data (args[3],
strlen (args[3]),
&ctx->coin_pub,
sizeof (ctx->coin_pub)))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (rc->connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_DEPOSITS_GET_INVALID_COIN_PUB,
args[3]);
}
TALER_MHD_parse_request_arg_auto_t (rc->connection,
"merchant_sig",
&ctx->merchant_sig);
TALER_MHD_parse_request_timeout (rc->connection,
&ctx->timeout);
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
{
if (GNUNET_OK !=
TALER_merchant_deposit_verify (&ctx->merchant,
&ctx->coin_pub,
&ctx->h_contract_terms,
&ctx->h_wire,
&ctx->merchant_sig))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (rc->connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_DEPOSITS_GET_MERCHANT_SIGNATURE_INVALID,
NULL);
}
}
}
return handle_track_transaction_request (ctx);
}
/* end of taler-exchange-httpd_deposits_get.c */