/*
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 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_purses_deposit.c
* @brief Handle /purses/$PID/deposit 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
#include
#include
#include
#include
#include "taler_dbevents.h"
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
#include "taler-exchange-httpd_purses_deposit.h"
#include "taler-exchange-httpd_responses.h"
#include "taler_exchangedb_lib.h"
#include "taler-exchange-httpd_keys.h"
/**
* Information about an individual coin being deposited.
*/
struct Coin
{
/**
* Public information about the coin.
*/
struct TALER_CoinPublicInfo cpi;
/**
* Signature affirming spending the coin.
*/
struct TALER_CoinSpendSignatureP coin_sig;
/**
* Amount to be put into the purse from this coin.
*/
struct TALER_Amount amount;
/**
* Deposit fee applicable for this coin.
*/
struct TALER_Amount deposit_fee;
/**
* Amount to be put into the purse from this coin.
*/
struct TALER_Amount amount_minus_fee;
/**
* ID of the coin in known_coins.
*/
uint64_t known_coin_id;
};
/**
* Closure for #deposit_transaction.
*/
struct PurseDepositContext
{
/**
* Public key of the purse we are creating.
*/
const struct TALER_PurseContractPublicKeyP *purse_pub;
/**
* Total amount to be put into the purse.
*/
struct TALER_Amount amount;
/**
* Total actually deposited by all the coins.
*/
struct TALER_Amount deposit_total;
/**
* When should the purse expire.
*/
struct GNUNET_TIME_Timestamp purse_expiration;
/**
* Hash of the contract (needed for signing).
*/
struct TALER_PrivateContractHashP h_contract_terms;
/**
* Our current time.
*/
struct GNUNET_TIME_Timestamp exchange_timestamp;
/**
* Array of coins being deposited.
*/
struct Coin *coins;
/**
* Length of the @e coins array.
*/
unsigned int num_coins;
/**
* Minimum age for deposits into this purse.
*/
uint32_t min_age;
};
/**
* Send confirmation of purse creation success to client.
*
* @param connection connection to the client
* @param pcc details about the request that succeeded
* @return MHD result code
*/
static MHD_RESULT
reply_deposit_success (struct MHD_Connection *connection,
const struct PurseDepositContext *pcc)
{
struct TALER_ExchangePublicKeyP pub;
struct TALER_ExchangeSignatureP sig;
enum TALER_ErrorCode ec;
if (TALER_EC_NONE !=
(ec = TALER_exchange_online_purse_created_sign (
&TEH_keys_exchange_sign_,
pcc->exchange_timestamp,
pcc->purse_expiration,
&pcc->amount,
&pcc->deposit_total,
pcc->purse_pub,
&pcc->h_contract_terms,
&pub,
&sig)))
{
GNUNET_break (0);
return TALER_MHD_reply_with_ec (connection,
ec,
NULL);
}
return TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_OK,
TALER_JSON_pack_amount ("total_deposited",
&pcc->deposit_total),
TALER_JSON_pack_amount ("purse_value_after_fees",
&pcc->amount),
GNUNET_JSON_pack_timestamp ("exchange_timestamp",
pcc->exchange_timestamp),
GNUNET_JSON_pack_timestamp ("purse_expiration",
pcc->purse_expiration),
GNUNET_JSON_pack_data_auto ("h_contract_terms",
&pcc->h_contract_terms),
GNUNET_JSON_pack_data_auto ("exchange_sig",
&sig),
GNUNET_JSON_pack_data_auto ("exchange_pub",
&pub));
}
/**
* Execute database transaction for /purses/$PID/deposit. Runs the transaction
* logic; 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 a `struct PurseDepositContext`
* @param connection MHD request context
* @param[out] mhd_ret set to MHD status on error
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
deposit_transaction (void *cls,
struct MHD_Connection *connection,
MHD_RESULT *mhd_ret)
{
struct PurseDepositContext *pcc = cls;
enum GNUNET_DB_QueryStatus qs;
qs = GNUNET_DB_STATUS_SUCCESS_NO_RESULTS;
for (unsigned int i = 0; inum_coins; i++)
{
struct Coin *coin = &pcc->coins[i];
bool balance_ok = false;
bool conflict = true;
qs = TEH_plugin->do_purse_deposit (TEH_plugin->cls,
pcc->purse_pub,
&coin->cpi.coin_pub,
&coin->amount,
&coin->coin_sig,
&coin->amount_minus_fee,
&balance_ok,
&conflict);
if (qs <= 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
TALER_LOG_WARNING (
"Failed to store purse deposit information in database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"do purse deposit");
return qs;
}
if (! balance_ok)
{
*mhd_ret
= TEH_RESPONSE_reply_coin_insufficient_funds (
connection,
TALER_EC_EXCHANGE_GENERIC_INSUFFICIENT_FUNDS,
&coin->cpi.denom_pub_hash,
&coin->cpi.coin_pub);
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (conflict)
{
struct TALER_Amount amount;
struct TALER_CoinSpendPublicKeyP coin_pub;
struct TALER_CoinSpendSignatureP coin_sig;
char *partner_url = NULL;
TEH_plugin->rollback (TEH_plugin->cls);
qs = TEH_plugin->get_purse_deposit (TEH_plugin->cls,
pcc->purse_pub,
&coin->cpi.coin_pub,
&amount,
&coin_sig,
&partner_url);
if (qs < 0)
{
GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs);
TALER_LOG_WARNING (
"Failed to fetch purse deposit information from database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"get purse deposit");
return GNUNET_DB_STATUS_HARD_ERROR;
}
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_CONFLICT,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_PURSE_DEPOSIT_CONFLICTING_META_DATA),
GNUNET_JSON_pack_data_auto ("coin_pub",
&coin_pub),
GNUNET_JSON_pack_data_auto ("coin_sig",
&coin_sig),
GNUNET_JSON_pack_allow_null (
GNUNET_JSON_pack_string ("partner_url",
partner_url)),
TALER_JSON_pack_amount ("amount",
&amount));
GNUNET_free (partner_url);
return GNUNET_DB_STATUS_HARD_ERROR;
}
}
return qs;
}
/**
* Parse a coin and check signature of the coin and the denomination
* signature over the coin.
*
* @param[in,out] connection our HTTP connection
* @param[in,out] pcc request context
* @param[out] coin coin to initialize
* @param jcoin coin to parse
* @return #GNUNET_OK on success, #GNUNET_NO if an error was returned,
* #GNUNET_SYSERR on failure and no error could be returned
*/
static enum GNUNET_GenericReturnValue
parse_coin (struct MHD_Connection *connection,
struct PurseDepositContext *pcc,
struct Coin *coin,
const json_t *jcoin)
{
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount ("amount",
TEH_currency,
&coin->amount),
GNUNET_JSON_spec_fixed_auto ("denom_pub_hash",
&coin->cpi.denom_pub_hash),
TALER_JSON_spec_denom_sig ("ub_sig",
&coin->cpi.denom_sig),
GNUNET_JSON_spec_mark_optional (
GNUNET_JSON_spec_fixed_auto ("h_age_commitment",
&coin->cpi.h_age_commitment),
&coin->cpi.no_age_commitment),
// FIXME-Oec: proof of age is missing!
GNUNET_JSON_spec_fixed_auto ("coin_sig",
&coin->coin_sig),
GNUNET_JSON_spec_fixed_auto ("coin_pub",
&coin->cpi.coin_pub),
GNUNET_JSON_spec_end ()
};
{
enum GNUNET_GenericReturnValue res;
res = TALER_MHD_parse_json_data (connection,
jcoin,
spec);
if (GNUNET_OK != res)
return res;
}
if (GNUNET_OK !=
TALER_wallet_purse_deposit_verify (TEH_base_url,
pcc->purse_pub,
&coin->amount,
&coin->cpi.coin_pub,
&coin->coin_sig))
{
TALER_LOG_WARNING ("Invalid signature on /purses/$PID/deposit request\n");
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_PURSE_DEPOSIT_COIN_SIGNATURE_INVALID,
TEH_base_url))
? GNUNET_NO : GNUNET_SYSERR;
}
/* check denomination exists and is valid */
{
struct TEH_DenominationKey *dk;
MHD_RESULT mret;
dk = TEH_keys_denomination_by_hash (&coin->cpi.denom_pub_hash,
connection,
&mret);
if (NULL == dk)
{
GNUNET_JSON_parse_free (spec);
return (MHD_YES == mret) ? GNUNET_NO : GNUNET_SYSERR;
}
if (0 > TALER_amount_cmp (&dk->meta.value,
&coin->amount))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_GENERIC_AMOUNT_EXCEEDS_DENOMINATION_VALUE,
NULL))
? GNUNET_NO : GNUNET_SYSERR;
}
if (GNUNET_TIME_absolute_is_past (dk->meta.expire_deposit.abs_time))
{
/* This denomination is past the expiration time for deposits */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TEH_RESPONSE_reply_expired_denom_pub_hash (
connection,
&coin->cpi.denom_pub_hash,
TALER_EC_EXCHANGE_GENERIC_DENOMINATION_EXPIRED,
"PURSE DEPOSIT"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (GNUNET_TIME_absolute_is_future (dk->meta.start.abs_time))
{
/* This denomination is not yet valid */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TEH_RESPONSE_reply_expired_denom_pub_hash (
connection,
&coin->cpi.denom_pub_hash,
TALER_EC_EXCHANGE_GENERIC_DENOMINATION_VALIDITY_IN_FUTURE,
"PURSE DEPOSIT"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (dk->recoup_possible)
{
/* This denomination has been revoked */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TEH_RESPONSE_reply_expired_denom_pub_hash (
connection,
&coin->cpi.denom_pub_hash,
TALER_EC_EXCHANGE_GENERIC_DENOMINATION_REVOKED,
"PURSE DEPOSIT"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (dk->denom_pub.cipher != coin->cpi.denom_sig.cipher)
{
/* denomination cipher and denomination signature cipher not the same */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_GENERIC_CIPHER_MISMATCH,
NULL))
? GNUNET_NO : GNUNET_SYSERR;
}
coin->deposit_fee = dk->meta.fees.deposit;
if (0 < TALER_amount_cmp (&coin->deposit_fee,
&coin->amount))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_DEPOSIT_NEGATIVE_VALUE_AFTER_FEE,
NULL);
}
GNUNET_assert (0 <=
TALER_amount_subtract (&coin->amount_minus_fee,
&coin->amount,
&coin->deposit_fee));
/* check coin signature */
switch (dk->denom_pub.cipher)
{
case TALER_DENOMINATION_RSA:
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_RSA]++;
break;
case TALER_DENOMINATION_CS:
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_CS]++;
break;
default:
break;
}
if (GNUNET_YES !=
TALER_test_coin_valid (&coin->cpi,
&dk->denom_pub))
{
TALER_LOG_WARNING ("Invalid coin passed for /deposit\n");
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_DENOMINATION_SIGNATURE_INVALID,
NULL))
? GNUNET_NO : GNUNET_SYSERR;
}
if (0 >
TALER_amount_add (&pcc->deposit_total,
&pcc->deposit_total,
&coin->amount_minus_fee))
{
GNUNET_break (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_FAILED_COMPUTE_AMOUNT,
"total deposit contribution");
}
}
{
MHD_RESULT mhd_ret = MHD_NO;
enum GNUNET_DB_QueryStatus qs;
/* make sure coin is 'known' in database */
for (unsigned int tries = 0; triescpi,
connection,
&coin->known_coin_id,
&mhd_ret);
/* no transaction => no serialization failures should be possible */
if (GNUNET_DB_STATUS_SOFT_ERROR != qs)
break;
}
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
{
GNUNET_break (0);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_COMMIT_FAILED,
"make_coin_known"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (qs < 0)
return (MHD_YES == mhd_ret) ? GNUNET_NO : GNUNET_SYSERR;
}
return GNUNET_OK;
}
MHD_RESULT
TEH_handler_purses_deposit (
struct MHD_Connection *connection,
const struct TALER_PurseContractPublicKeyP *purse_pub,
const json_t *root)
{
struct PurseDepositContext pcc = {
.purse_pub = purse_pub,
.exchange_timestamp = GNUNET_TIME_timestamp_get ()
};
json_t *deposits;
json_t *deposit;
unsigned int idx;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_json ("deposits",
&deposits),
GNUNET_JSON_spec_end ()
};
{
enum GNUNET_GenericReturnValue res;
res = TALER_MHD_parse_json_data (connection,
root,
spec);
if (GNUNET_SYSERR == res)
{
GNUNET_break (0);
return MHD_NO; /* hard failure */
}
if (GNUNET_NO == res)
{
GNUNET_break_op (0);
return MHD_YES; /* failure */
}
}
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (TEH_currency,
&pcc.deposit_total));
pcc.num_coins = json_array_size (deposits);
if ( (0 == pcc.num_coins) ||
(pcc.num_coins > TALER_MAX_FRESH_COINS) )
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
"deposits");
}
{
enum GNUNET_DB_QueryStatus qs;
struct GNUNET_TIME_Timestamp merge_timestamp;
qs = TEH_plugin->select_purse (
TEH_plugin->cls,
pcc.purse_pub,
&pcc.purse_expiration,
&pcc.amount,
&pcc.deposit_total,
&pcc.h_contract_terms,
&merge_timestamp);
switch (qs)
{
case GNUNET_DB_STATUS_HARD_ERROR:
GNUNET_break (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select purse");
case GNUNET_DB_STATUS_SOFT_ERROR:
GNUNET_break (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select purse");
case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_EXCHANGE_GENERIC_PURSE_UNKNOWN,
NULL);
case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT:
break; /* handled below */
}
if (GNUNET_TIME_absolute_is_past (pcc.purse_expiration.abs_time))
{
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_GONE,
TALER_EC_EXCHANGE_GENERIC_PURSE_EXPIRED,
NULL);
}
}
/* parse deposits */
pcc.coins = GNUNET_new_array (pcc.num_coins,
struct Coin);
json_array_foreach (deposits, idx, deposit)
{
enum GNUNET_GenericReturnValue res;
struct Coin *coin = &pcc.coins[idx];
res = parse_coin (connection,
&pcc,
coin,
deposit);
if (GNUNET_OK != res)
{
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return (GNUNET_NO == res) ? MHD_YES : MHD_NO;
}
}
if (GNUNET_SYSERR ==
TEH_plugin->preflight (TEH_plugin->cls))
{
GNUNET_break (0);
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_START_FAILED,
"preflight failure");
}
/* execute transaction */
{
MHD_RESULT mhd_ret;
if (GNUNET_OK !=
TEH_DB_run_transaction (connection,
"execute purse deposit",
TEH_MT_REQUEST_PURSE_DEPOSIT,
&mhd_ret,
&deposit_transaction,
&pcc))
{
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return mhd_ret;
}
}
{
struct TALER_PurseEventP rep = {
.header.size = htons (sizeof (rep)),
.header.type = htons (TALER_DBEVENT_EXCHANGE_PURSE_DEPOSITED),
.purse_pub = *pcc.purse_pub
};
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Notifying about purse deposit %s\n",
TALER_B2S (pcc.purse_pub));
TEH_plugin->event_notify (TEH_plugin->cls,
&rep.header,
NULL,
0);
}
/* generate regular response */
{
MHD_RESULT res;
res = reply_deposit_success (connection,
&pcc);
GNUNET_free (pcc.coins);
GNUNET_JSON_parse_free (spec);
return res;
}
}
/* end of taler-exchange-httpd_purses_deposit.c */