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/*
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_purse_merge.c
* @brief Implementation of the client to merge a purse
* into an account
* @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 purse merge with deposit handle
*/
struct TALER_EXCHANGE_AccountMergeHandle
{
/**
* The connection to exchange this request handle will use
*/
struct TALER_EXCHANGE_Handle *exchange;
/**
* The url for this request.
*/
char *url;
/**
* Context for #TEH_curl_easy_post(). Keeps the data that must
* persist for Curl to make the upload.
*/
struct TALER_CURL_PostContext ctx;
/**
* Handle for the request.
*/
struct GNUNET_CURL_Job *job;
/**
* Function to call with the result.
*/
TALER_EXCHANGE_AccountMergeCallback cb;
/**
* Closure for @a cb.
*/
void *cb_cls;
/**
* Base URL of the provider hosting the @e reserve_pub.
*/
char *provider_url;
/**
* Expected value in the purse after fees.
*/
struct TALER_Amount purse_value_after_fees;
/**
* Public key of the reserve public key.
*/
struct TALER_ReservePublicKeyP reserve_pub;
/**
* Public key of the purse.
*/
struct TALER_PurseContractPublicKeyP purse_pub;
/**
* Hash over the purse's contrac terms.
*/
struct TALER_PrivateContractHashP h_contract_terms;
/**
* When does the purse expire.
*/
struct GNUNET_TIME_Timestamp purse_expiration;
};
/**
* Function called when we're done processing the
* HTTP /purse/$PID/merge request.
*
* @param cls the `struct TALER_EXCHANGE_AccountMergeHandle`
* @param response_code HTTP response code, 0 on error
* @param response parsed JSON result, NULL on error
*/
static void
handle_purse_merge_finished (void *cls,
long response_code,
const void *response)
{
struct TALER_EXCHANGE_AccountMergeHandle *pch = cls;
const json_t *j = response;
struct TALER_EXCHANGE_AccountMergeResponse dr = {
.hr.reply = j,
.hr.http_status = (unsigned int) response_code
};
pch->job = NULL;
switch (response_code)
{
case 0:
dr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
break;
case MHD_HTTP_OK:
{
const struct TALER_EXCHANGE_Keys *key_state;
struct GNUNET_TIME_Timestamp etime;
struct TALER_Amount total_deposited;
struct TALER_ExchangeSignatureP exchange_sig;
struct TALER_ExchangePublicKeyP exchange_pub;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&exchange_pub),
GNUNET_JSON_spec_timestamp ("exchange_timestamp",
&etime),
TALER_JSON_spec_amount ("total_deposited",
pch->purse_value_after_fees.currency,
&total_deposited),
GNUNET_JSON_spec_end ()
};
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 (pch->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_PURSE_MERGE_EXCHANGE_SIGNATURE_INVALID;
break;
}
if (GNUNET_OK !=
TALER_exchange_online_purse_merged_verify (
etime,
pch->purse_expiration,
&pch->purse_value_after_fees,
&pch->purse_pub,
&pch->h_contract_terms,
&pch->reserve_pub,
pch->provider_url,
&exchange_pub,
&exchange_sig))
{
GNUNET_break_op (0);
dr.hr.http_status = 0;
dr.hr.ec = TALER_EC_EXCHANGE_PURSE_MERGE_EXCHANGE_SIGNATURE_INVALID;
break;
}
}
break;
case MHD_HTTP_BAD_REQUEST:
/* This should never happen, either us or the exchange is buggy
(or API version conflict); just pass JSON reply to the application */
dr.hr.ec = TALER_JSON_get_error_code (j);
dr.hr.hint = TALER_JSON_get_error_hint (j);
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);
/* Nothing really to verify, this should never
happen, we should pass the JSON reply to the application */
break;
case MHD_HTTP_CONFLICT:
// FIXME: check reply!
break;
case MHD_HTTP_GONE:
/* could happen if denomination was revoked */
/* Note: one might want to check /keys for revocation
signature here, alas tricky in case our /keys
is outdated => left to clients */
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 deposit\n",
(unsigned int) response_code,
dr.hr.ec);
GNUNET_break_op (0);
break;
}
pch->cb (pch->cb_cls,
&dr);
TALER_EXCHANGE_account_merge_cancel (pch);
}
struct TALER_EXCHANGE_AccountMergeHandle *
TALER_EXCHANGE_account_merge (
struct TALER_EXCHANGE_Handle *exchange,
const char *reserve_exchange_url,
const struct TALER_ReservePrivateKeyP *reserve_priv,
const struct TALER_PurseContractPublicKeyP *purse_pub,
const struct TALER_PurseMergePrivateKeyP *merge_priv,
const struct TALER_PrivateContractHashP *h_contract_terms,
uint8_t min_age,
const struct TALER_Amount *purse_value_after_fees,
struct GNUNET_TIME_Timestamp purse_expiration,
struct GNUNET_TIME_Timestamp merge_timestamp,
TALER_EXCHANGE_AccountMergeCallback cb,
void *cb_cls)
{
struct TALER_EXCHANGE_AccountMergeHandle *pch;
struct GNUNET_CURL_Context *ctx;
json_t *merge_obj;
CURL *eh;
struct TALER_PurseMergeSignatureP merge_sig;
struct TALER_ReserveSignatureP reserve_sig;
char arg_str[sizeof (pch->purse_pub) * 2 + 32];
char *reserve_url;
pch = GNUNET_new (struct TALER_EXCHANGE_AccountMergeHandle);
pch->exchange = exchange;
pch->cb = cb;
pch->cb_cls = cb_cls;
pch->purse_pub = *purse_pub;
pch->h_contract_terms = *h_contract_terms;
pch->purse_expiration = purse_expiration;
pch->purse_value_after_fees = *purse_value_after_fees;
if (NULL == reserve_exchange_url)
pch->provider_url = GNUNET_strdup (exchange->url);
else
pch->provider_url = GNUNET_strdup (reserve_exchange_url);
GNUNET_CRYPTO_eddsa_key_get_public (&reserve_priv->eddsa_priv,
&pch->reserve_pub.eddsa_pub);
GNUNET_assert (GNUNET_YES ==
TEAH_handle_is_ready (exchange));
{
char pub_str[sizeof (*purse_pub) * 2];
char *end;
end = GNUNET_STRINGS_data_to_string (
purse_pub,
sizeof (*purse_pub),
pub_str,
sizeof (pub_str));
*end = '\0';
GNUNET_snprintf (arg_str,
sizeof (arg_str),
"/purses/%s/merge",
pub_str);
}
{
char pub_str[sizeof (pch->reserve_pub) * 2];
char *end;
const char *exchange_url;
bool is_http;
end = GNUNET_STRINGS_data_to_string (
&pch->reserve_pub,
sizeof (pch->reserve_pub),
pub_str,
sizeof (pub_str));
*end = '\0';
if (0 == strncmp (pch->provider_url,
"http://",
strlen ("http://")))
{
is_http = true;
exchange_url = &pch->provider_url[strlen ("http://")];
}
else if (0 == strncmp (pch->provider_url,
"https://",
strlen ("https://")))
{
is_http = false;
exchange_url = &pch->provider_url[strlen ("https://")];
}
else
{
GNUNET_break (0);
GNUNET_free (pch->provider_url);
GNUNET_free (pch);
return NULL;
}
/* exchange_url includes trailing '/' */
GNUNET_asprintf (&reserve_url,
"payto://%s/%s%s",
is_http ? "taler+http" : "taler",
exchange_url,
pub_str);
}
pch->url = TEAH_path_to_url (exchange,
arg_str);
if (NULL == pch->url)
{
GNUNET_break (0);
GNUNET_free (pch);
return NULL;
}
TALER_wallet_purse_merge_sign (reserve_url,
merge_timestamp,
purse_pub,
merge_priv,
&merge_sig);
TALER_wallet_account_merge_sign (merge_timestamp,
purse_pub,
purse_expiration,
h_contract_terms,
purse_value_after_fees,
min_age,
reserve_priv,
&reserve_sig);
merge_obj = GNUNET_JSON_PACK (
GNUNET_JSON_pack_string ("payto_uri",
reserve_url),
GNUNET_JSON_pack_data_auto ("merge_sig",
&merge_sig),
GNUNET_JSON_pack_data_auto ("reserve_sig",
&reserve_sig),
GNUNET_JSON_pack_timestamp ("merge_timestamp",
merge_timestamp));
GNUNET_assert (NULL != merge_obj);
eh = TALER_EXCHANGE_curl_easy_get_ (pch->url);
if ( (NULL == eh) ||
(GNUNET_OK !=
TALER_curl_easy_post (&pch->ctx,
eh,
merge_obj)) )
{
GNUNET_break (0);
if (NULL != eh)
curl_easy_cleanup (eh);
json_decref (merge_obj);
GNUNET_free (pch->url);
GNUNET_free (pch);
return NULL;
}
json_decref (merge_obj);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"URL for purse merge: `%s'\n",
pch->url);
ctx = TEAH_handle_to_context (exchange);
pch->job = GNUNET_CURL_job_add2 (ctx,
eh,
pch->ctx.headers,
&handle_purse_merge_finished,
pch);
return pch;
}
void
TALER_EXCHANGE_account_merge_cancel (
struct TALER_EXCHANGE_AccountMergeHandle *pch)
{
if (NULL != pch->job)
{
GNUNET_CURL_job_cancel (pch->job);
pch->job = NULL;
}
GNUNET_free (pch->url);
GNUNET_free (pch->provider_url);
TALER_curl_easy_post_finished (&pch->ctx);
GNUNET_free (pch);
}
/* end of exchange_api_purse_merge.c */
|