exchange/src/lib/exchange_api_purses_get.c
2022-05-17 11:21:20 +02:00

291 lines
8.5 KiB
C

/*
This file is part of TALER
Copyright (C) 2022 Taler Systems SA
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU 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 General Public License for more details.
You should have received a copy of the GNU General Public License along with
TALER; see the file COPYING. If not, see
<http://www.gnu.org/licenses/>
*/
/**
* @file lib/exchange_api_purses_get.c
* @brief Implementation of the /purses/ GET request
* @author Christian Grothoff
*/
#include "platform.h"
#include <jansson.h>
#include <microhttpd.h> /* just for HTTP status codes */
#include <gnunet/gnunet_util_lib.h>
#include <gnunet/gnunet_json_lib.h>
#include <gnunet/gnunet_curl_lib.h>
#include "taler_json_lib.h"
#include "taler_exchange_service.h"
#include "exchange_api_handle.h"
#include "taler_signatures.h"
#include "exchange_api_curl_defaults.h"
/**
* @brief A Contract Get Handle
*/
struct TALER_EXCHANGE_PurseGetHandle
{
/**
* The connection to exchange this request handle will use
*/
struct TALER_EXCHANGE_Handle *exchange;
/**
* The url for this request.
*/
char *url;
/**
* Handle for the request.
*/
struct GNUNET_CURL_Job *job;
/**
* Function to call with the result.
*/
TALER_EXCHANGE_PurseGetCallback cb;
/**
* Closure for @a cb.
*/
void *cb_cls;
};
/**
* Function called when we're done processing the
* HTTP /purses/$PID GET request.
*
* @param cls the `struct TALER_EXCHANGE_PurseGetHandle`
* @param response_code HTTP response code, 0 on error
* @param response parsed JSON result, NULL on error
*/
static void
handle_purse_get_finished (void *cls,
long response_code,
const void *response)
{
struct TALER_EXCHANGE_PurseGetHandle *pgh = cls;
const json_t *j = response;
struct TALER_EXCHANGE_PurseGetResponse dr = {
.hr.reply = j,
.hr.http_status = (unsigned int) response_code
};
pgh->job = NULL;
switch (response_code)
{
case 0:
dr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
break;
case MHD_HTTP_OK:
{
struct TALER_ExchangePublicKeyP exchange_pub;
struct TALER_ExchangeSignatureP exchange_sig;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_timestamp ("merge_timestamp",
&dr.details.success.merge_timestamp),
GNUNET_JSON_spec_timestamp ("deposit_timestamp",
&dr.details.success.deposit_timestamp),
TALER_JSON_spec_amount_any ("balance",
&dr.details.success.balance),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&exchange_pub),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&exchange_sig),
GNUNET_JSON_spec_end ()
};
const struct TALER_EXCHANGE_Keys *key_state;
if (GNUNET_OK !=
GNUNET_JSON_parse (j,
spec,
NULL, NULL))
{
GNUNET_break_op (0);
dr.hr.http_status = 0;
dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
break;
}
key_state = TALER_EXCHANGE_get_keys (pgh->exchange);
if (GNUNET_OK !=
TALER_EXCHANGE_test_signing_key (key_state,
&exchange_pub))
{
GNUNET_break_op (0);
dr.hr.http_status = 0;
dr.hr.ec = TALER_EC_EXCHANGE_PURSES_GET_INVALID_SIGNATURE_BY_EXCHANGE;
break;
}
if (GNUNET_OK !=
TALER_exchange_online_purse_status_verify (
dr.details.success.merge_timestamp,
dr.details.success.deposit_timestamp,
&dr.details.success.balance,
&exchange_pub,
&exchange_sig))
{
GNUNET_break_op (0);
dr.hr.http_status = 0;
dr.hr.ec = TALER_EC_EXCHANGE_PURSES_GET_INVALID_SIGNATURE_BY_EXCHANGE;
break;
}
pgh->cb (pgh->cb_cls,
&dr);
TALER_EXCHANGE_purse_get_cancel (pgh);
return;
}
case MHD_HTTP_BAD_REQUEST:
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
/* This should never happen, either us or the exchange is buggy
(or API version conflict); just pass JSON reply to the application */
break;
case MHD_HTTP_FORBIDDEN:
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
/* 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 */
break;
case MHD_HTTP_NOT_FOUND:
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
/* Exchange does not know about transaction;
we should pass the reply to the application */
break;
case MHD_HTTP_GONE:
/* purse expired */
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
break;
case MHD_HTTP_INTERNAL_SERVER_ERROR:
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
/* Server had an internal issue; we should retry, but this API
leaves this to the application */
break;
default:
/* unexpected response code */
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Unexpected response code %u/%d for exchange GET purses\n",
(unsigned int) response_code,
(int) dr.hr.ec);
GNUNET_break_op (0);
break;
}
pgh->cb (pgh->cb_cls,
&dr);
TALER_EXCHANGE_purse_get_cancel (pgh);
}
struct TALER_EXCHANGE_PurseGetHandle *
TALER_EXCHANGE_purse_get (
struct TALER_EXCHANGE_Handle *exchange,
const struct TALER_PurseContractPublicKeyP *purse_pub,
struct GNUNET_TIME_Relative timeout,
bool wait_for_merge,
TALER_EXCHANGE_PurseGetCallback cb,
void *cb_cls)
{
struct TALER_EXCHANGE_PurseGetHandle *pgh;
CURL *eh;
char arg_str[sizeof (*purse_pub) * 2 + 64];
if (GNUNET_YES !=
TEAH_handle_is_ready (exchange))
{
GNUNET_break (0);
return NULL;
}
pgh = GNUNET_new (struct TALER_EXCHANGE_PurseGetHandle);
pgh->exchange = exchange;
pgh->cb = cb;
pgh->cb_cls = cb_cls;
{
char cpub_str[sizeof (*purse_pub) * 2];
char *end;
char timeout_str[32];
end = GNUNET_STRINGS_data_to_string (purse_pub,
sizeof (*purse_pub),
cpub_str,
sizeof (cpub_str));
*end = '\0';
GNUNET_snprintf (timeout_str,
sizeof (timeout_str),
"%llu",
(unsigned long long)
(timeout.rel_value_us
/ GNUNET_TIME_UNIT_MILLISECONDS.rel_value_us));
if (GNUNET_TIME_relative_is_zero (timeout))
GNUNET_snprintf (arg_str,
sizeof (arg_str),
"/purses/%s/%s",
cpub_str,
wait_for_merge ? "merge" : "deposit");
else
GNUNET_snprintf (arg_str,
sizeof (arg_str),
"/purses/%s/%s?timeout_ms=%s",
cpub_str,
wait_for_merge ? "merge" : "deposit",
timeout_str);
}
pgh->url = TEAH_path_to_url (exchange,
arg_str);
if (NULL == pgh->url)
{
GNUNET_free (pgh);
return NULL;
}
eh = TALER_EXCHANGE_curl_easy_get_ (pgh->url);
if (NULL == eh)
{
GNUNET_break (0);
GNUNET_free (pgh->url);
GNUNET_free (pgh);
return NULL;
}
pgh->job = GNUNET_CURL_job_add (TEAH_handle_to_context (exchange),
eh,
&handle_purse_get_finished,
pgh);
return pgh;
}
void
TALER_EXCHANGE_purse_get_cancel (
struct TALER_EXCHANGE_PurseGetHandle *pgh)
{
if (NULL != pgh->job)
{
GNUNET_CURL_job_cancel (pgh->job);
pgh->job = NULL;
}
GNUNET_free (pgh->url);
GNUNET_free (pgh);
}
/* end of exchange_api_purses_get.c */