exchange/src/lib/auditor_api_exchanges.c
2021-10-27 09:23:12 +02:00

271 lines
7.4 KiB
C

/*
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 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/auditor_api_exchanges.c
* @brief Implementation of the /exchanges request of the auditor's HTTP API
* @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_auditor_service.h"
#include "auditor_api_handle.h"
#include "taler_signatures.h"
#include "auditor_api_curl_defaults.h"
/**
* How many exchanges do we allow a single auditor to
* audit at most?
*/
#define MAX_EXCHANGES 1024
/**
* @brief A ListExchanges Handle
*/
struct TALER_AUDITOR_ListExchangesHandle
{
/**
* The connection to auditor this request handle will use
*/
struct TALER_AUDITOR_Handle *auditor;
/**
* The url for this request.
*/
char *url;
/**
* Handle for the request.
*/
struct GNUNET_CURL_Job *job;
/**
* Function to call with the result.
*/
TALER_AUDITOR_ListExchangesResultCallback cb;
/**
* Closure for @a cb.
*/
void *cb_cls;
};
/**
* Function called when we're done processing the
* HTTP /exchanges request.
*
* @param cls the `struct TALER_AUDITOR_ListExchangesHandle`
* @param response_code HTTP response code, 0 on error
* @param djson parsed JSON result, NULL on error
*/
static void
handle_exchanges_finished (void *cls,
long response_code,
const void *djson)
{
const json_t *json = djson;
const json_t *ja;
unsigned int ja_len;
struct TALER_AUDITOR_ListExchangesHandle *leh = cls;
struct TALER_AUDITOR_HttpResponse hr = {
.reply = json,
.http_status = (unsigned int) response_code
};
leh->job = NULL;
switch (response_code)
{
case 0:
hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
break;
case MHD_HTTP_OK:
ja = json_object_get (json,
"exchanges");
if ( (NULL == ja) ||
(! json_is_array (ja)) )
{
GNUNET_break (0);
hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
hr.http_status = 0;
break;
}
ja_len = json_array_size (ja);
if (ja_len > MAX_EXCHANGES)
{
GNUNET_break (0);
hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
hr.http_status = 0;
break;
}
{
struct TALER_AUDITOR_ExchangeInfo ei[ja_len];
bool ok;
ok = true;
for (unsigned int i = 0; i<ja_len; i++)
{
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("master_pub", &ei[i].master_pub),
GNUNET_JSON_spec_string ("exchange_url", &ei[i].exchange_url),
GNUNET_JSON_spec_end ()
};
if (GNUNET_OK !=
GNUNET_JSON_parse (json_array_get (ja,
i),
spec,
NULL, NULL))
{
GNUNET_break_op (0);
ok = false;
hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
hr.http_status = 0;
break;
}
}
if (! ok)
break;
leh->cb (leh->cb_cls,
&hr,
ja_len,
ei);
TALER_AUDITOR_list_exchanges_cancel (leh);
return;
}
case MHD_HTTP_BAD_REQUEST:
/* This should never happen, either us or the auditor is buggy
(or API version conflict); just pass JSON reply to the application */
hr.ec = TALER_JSON_get_error_code (json);
hr.hint = TALER_JSON_get_error_hint (json);
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 (json);
hr.hint = TALER_JSON_get_error_hint (json);
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 (json);
hr.hint = TALER_JSON_get_error_hint (json);
break;
default:
/* unexpected response code */
hr.ec = TALER_JSON_get_error_code (json);
hr.hint = TALER_JSON_get_error_hint (json);
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Unexpected response code %u/%d for auditor list-exchanges request\n",
(unsigned int) response_code,
(int) hr.ec);
GNUNET_break_op (0);
break;
}
if (NULL != leh->cb)
leh->cb (leh->cb_cls,
&hr,
0,
NULL);
TALER_AUDITOR_list_exchanges_cancel (leh);
}
/**
* Submit an /exchanges request to the auditor and get the
* auditor's response. If the auditor's reply is not
* well-formed, we return an HTTP status code of zero to @a cb.
*
* @param auditor the auditor handle; the auditor must be ready to operate
* @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_AUDITOR_ListExchangesHandle *
TALER_AUDITOR_list_exchanges (struct TALER_AUDITOR_Handle *auditor,
TALER_AUDITOR_ListExchangesResultCallback cb,
void *cb_cls)
{
struct TALER_AUDITOR_ListExchangesHandle *leh;
struct GNUNET_CURL_Context *ctx;
CURL *eh;
GNUNET_assert (GNUNET_YES ==
TALER_AUDITOR_handle_is_ready_ (auditor));
leh = GNUNET_new (struct TALER_AUDITOR_ListExchangesHandle);
leh->auditor = auditor;
leh->cb = cb;
leh->cb_cls = cb_cls;
leh->url = TALER_AUDITOR_path_to_url_ (auditor,
"/exchanges");
if (NULL == leh->url)
{
GNUNET_free (leh);
return NULL;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"URL for list-exchanges: `%s'\n",
leh->url);
eh = TALER_AUDITOR_curl_easy_get_ (leh->url);
if (NULL == eh)
{
GNUNET_break (0);
GNUNET_free (leh->url);
GNUNET_free (leh);
return NULL;
}
ctx = TALER_AUDITOR_handle_to_context_ (auditor);
leh->job = GNUNET_CURL_job_add (ctx,
eh,
&handle_exchanges_finished,
leh);
return leh;
}
/**
* Cancel a list exchanges request. This function cannot be used
* on a request handle if a response is already served for it.
*
* @param leh the list exchanges request handle
*/
void
TALER_AUDITOR_list_exchanges_cancel (
struct TALER_AUDITOR_ListExchangesHandle *leh)
{
if (NULL != leh->job)
{
GNUNET_CURL_job_cancel (leh->job);
leh->job = NULL;
}
GNUNET_free (leh->url);
GNUNET_free (leh);
}
/* end of auditor_api_exchanges.c */