exchange/src/auditor/taler-auditor-httpd_deposit-confirmation.c
2021-12-14 16:04:40 +01:00

351 lines
13 KiB
C

/*
This file is part of TALER
Copyright (C) 2014-2020 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 <http://www.gnu.org/licenses/>
*/
/**
* @file taler-auditor-httpd_deposit-confirmation.c
* @brief Handle /deposit-confirmation requests; parses the POST and JSON and
* verifies the coin signature before handing things off
* to the database.
* @author Christian Grothoff
*/
#include "platform.h"
#include <gnunet/gnunet_util_lib.h>
#include <gnunet/gnunet_json_lib.h>
#include <jansson.h>
#include <microhttpd.h>
#include <pthread.h>
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
#include "taler-auditor-httpd.h"
#include "taler-auditor-httpd_deposit-confirmation.h"
/**
* Cache of already verified exchange signing keys. Maps the hash of the
* `struct TALER_ExchangeSigningKeyValidityPS` to the (static) string
* "verified" or "revoked". Access to this map is guarded by the #lock.
*/
static struct GNUNET_CONTAINER_MultiHashMap *cache;
/**
* Lock for operations on #cache.
*/
static pthread_mutex_t lock;
/**
* We have parsed the JSON information about the deposit, do some
* basic sanity checks (especially that the signature on the coin is
* valid, and that this type of coin exists) and then execute the
* deposit.
*
* @param connection the MHD connection to handle
* @param dc information about the deposit confirmation
* @param es information about the exchange's signing key
* @return MHD result code
*/
static MHD_RESULT
verify_and_execute_deposit_confirmation (
struct MHD_Connection *connection,
const struct TALER_AUDITORDB_DepositConfirmation *dc,
const struct TALER_AUDITORDB_ExchangeSigningKey *es)
{
enum GNUNET_DB_QueryStatus qs;
struct GNUNET_HashCode h;
const char *cached;
struct TALER_ExchangeSigningKeyValidityPS skv = {
.purpose.purpose = htonl (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY),
.purpose.size = htonl (sizeof (struct TALER_ExchangeSigningKeyValidityPS)),
.start = GNUNET_TIME_timestamp_hton (es->ep_start),
.expire = GNUNET_TIME_timestamp_hton (es->ep_expire),
.end = GNUNET_TIME_timestamp_hton (es->ep_end),
.signkey_pub = es->exchange_pub
};
if (GNUNET_TIME_absolute_is_future (es->ep_start.abs_time) ||
GNUNET_TIME_absolute_is_past (es->ep_expire.abs_time) )
{
/* Signing key expired */
TALER_LOG_WARNING ("Expired exchange signing key\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_AUDITOR_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
"master signature expired");
}
/* check our cache */
GNUNET_CRYPTO_hash (&skv,
sizeof (skv),
&h);
GNUNET_assert (0 == pthread_mutex_lock (&lock));
cached = GNUNET_CONTAINER_multihashmap_get (cache,
&h);
GNUNET_assert (0 == pthread_mutex_unlock (&lock));
if (GNUNET_SYSERR ==
TAH_plugin->preflight (TAH_plugin->cls))
{
GNUNET_break (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_SETUP_FAILED,
NULL);
}
if (NULL == cached)
{
/* Not in cache, need to verify the signature, persist it, and possibly cache it */
if (GNUNET_OK !=
TALER_exchange_offline_signkey_validity_verify (
&es->exchange_pub,
es->ep_start,
es->ep_expire,
es->ep_end,
&es->master_public_key,
&es->master_sig))
{
TALER_LOG_WARNING ("Invalid signature on exchange signing key\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_AUDITOR_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
"master signature invalid");
}
/* execute transaction */
qs = TAH_plugin->insert_exchange_signkey (TAH_plugin->cls,
es);
if (0 > qs)
{
GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
TALER_LOG_WARNING ("Failed to store exchange signing key in database\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"exchange signing key");
}
cached = "verified";
}
if (0 == strcmp (cached,
"verified"))
{
struct TALER_MasterSignatureP master_sig;
/* check for revocation */
qs = TAH_eplugin->lookup_signkey_revocation (TAH_eplugin->cls,
&es->exchange_pub,
&master_sig);
if (0 > qs)
{
GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
TALER_LOG_WARNING (
"Failed to check for signing key revocation in database\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"exchange signing key revocation");
}
if (0 < qs)
cached = "revoked";
}
/* Cache it, due to concurreny it might already be in the cache,
so we do not cache it twice but also don't insist on the 'put' to
succeed. */
GNUNET_assert (0 == pthread_mutex_lock (&lock));
(void) GNUNET_CONTAINER_multihashmap_put (cache,
&h,
(void *) cached,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
GNUNET_assert (0 == pthread_mutex_unlock (&lock));
if (0 == strcmp (cached,
"revoked"))
{
TALER_LOG_WARNING (
"Invalid signature on /deposit-confirmation request: key was revoked\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_GONE,
TALER_EC_AUDITOR_EXCHANGE_SIGNING_KEY_REVOKED,
"exchange signing key was revoked");
}
/* check deposit confirmation signature */
if (GNUNET_OK !=
TALER_exchange_deposit_confirm_verify (&dc->h_contract_terms,
&dc->h_wire,
NULL /* h_extensions! */,
dc->exchange_timestamp,
dc->wire_deadline,
dc->refund_deadline,
&dc->amount_without_fee,
&dc->coin_pub,
&dc->merchant,
&dc->exchange_pub,
&dc->exchange_sig))
{
TALER_LOG_WARNING (
"Invalid signature on /deposit-confirmation request\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_AUDITOR_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
"exchange signature invalid");
}
/* execute transaction */
qs = TAH_plugin->insert_deposit_confirmation (TAH_plugin->cls,
dc);
if (0 > qs)
{
GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
TALER_LOG_WARNING ("Failed to store /deposit-confirmation in database\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"deposit confirmation");
}
return TALER_MHD_REPLY_JSON_PACK (connection,
MHD_HTTP_OK,
GNUNET_JSON_pack_string ("status",
"DEPOSIT_CONFIRMATION_OK"));
}
/**
* Handle a "/deposit-confirmation" request. Parses the JSON, and, if
* successful, passes the JSON data to #verify_and_execute_deposit_confirmation()
* to further check the details of the operation specified. If
* everything checks out, this will ultimately lead to the "/deposit-confirmation"
* being stored in the database.
*
* @param rh context of the handler
* @param connection the MHD connection to handle
* @param[in,out] connection_cls the connection's closure (can be updated)
* @param upload_data upload data
* @param[in,out] upload_data_size number of bytes (left) in @a upload_data
* @return MHD result code
*/
MHD_RESULT
TAH_DEPOSIT_CONFIRMATION_handler (struct TAH_RequestHandler *rh,
struct MHD_Connection *connection,
void **connection_cls,
const char *upload_data,
size_t *upload_data_size)
{
struct TALER_AUDITORDB_DepositConfirmation dc;
struct TALER_AUDITORDB_ExchangeSigningKey es;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
&dc.h_contract_terms),
GNUNET_JSON_spec_fixed_auto ("h_extensions",
&dc.h_extensions),
GNUNET_JSON_spec_fixed_auto ("h_wire",
&dc.h_wire),
GNUNET_JSON_spec_timestamp ("exchange_timestamp",
&dc.exchange_timestamp),
GNUNET_JSON_spec_timestamp ("refund_deadline",
&dc.refund_deadline),
GNUNET_JSON_spec_timestamp ("wire_deadline",
&dc.wire_deadline),
TALER_JSON_spec_amount ("amount_without_fee",
TAH_currency,
&dc.amount_without_fee),
GNUNET_JSON_spec_fixed_auto ("coin_pub",
&dc.coin_pub),
GNUNET_JSON_spec_fixed_auto ("merchant_pub",
&dc.merchant),
GNUNET_JSON_spec_fixed_auto ("exchange_sig",
&dc.exchange_sig),
GNUNET_JSON_spec_fixed_auto ("exchange_pub",
&dc.exchange_pub),
GNUNET_JSON_spec_fixed_auto ("master_pub",
&es.master_public_key),
GNUNET_JSON_spec_timestamp ("ep_start",
&es.ep_start),
GNUNET_JSON_spec_timestamp ("ep_expire",
&es.ep_expire),
GNUNET_JSON_spec_timestamp ("ep_end",
&es.ep_end),
GNUNET_JSON_spec_fixed_auto ("master_sig",
&es.master_sig),
GNUNET_JSON_spec_end ()
};
(void) rh;
(void) connection_cls;
(void) upload_data;
(void) upload_data_size;
{
json_t *json;
enum GNUNET_GenericReturnValue res;
res = TALER_MHD_parse_post_json (connection,
connection_cls,
upload_data,
upload_data_size,
&json);
if (GNUNET_SYSERR == res)
return MHD_NO;
if ( (GNUNET_NO == res) ||
(NULL == json) )
return MHD_YES;
res = TALER_MHD_parse_json_data (connection,
json,
spec);
json_decref (json);
if (GNUNET_SYSERR == res)
return MHD_NO; /* hard failure */
if (GNUNET_NO == res)
return MHD_YES; /* failure */
}
es.exchange_pub = dc.exchange_pub; /* used twice! */
dc.master_public_key = es.master_public_key;
{
MHD_RESULT res;
res = verify_and_execute_deposit_confirmation (connection,
&dc,
&es);
GNUNET_JSON_parse_free (spec);
return res;
}
}
/**
* Initialize subsystem.
*/
void
TEAH_DEPOSIT_CONFIRMATION_init (void)
{
cache = GNUNET_CONTAINER_multihashmap_create (32,
GNUNET_NO);
GNUNET_assert (0 == pthread_mutex_init (&lock, NULL));
}
/**
* Shut down subsystem.
*/
void
TEAH_DEPOSIT_CONFIRMATION_done (void)
{
GNUNET_CONTAINER_multihashmap_destroy (cache);
cache = NULL;
GNUNET_assert (0 == pthread_mutex_destroy (&lock));
}
/* end of taler-auditor-httpd_deposit-confirmation.c */