/*
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_create.c
* @brief Handle /purses/$PID/create requests; parses the POST and JSON and
* verifies the coin signature before handing things off
* to the database.
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include
#include
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
#include "taler-exchange-httpd_common_deposit.h"
#include "taler-exchange-httpd_purses_create.h"
#include "taler-exchange-httpd_responses.h"
#include "taler_exchangedb_lib.h"
#include "taler-exchange-httpd_keys.h"
/**
* Closure for #create_transaction.
*/
struct PurseCreateContext
{
/**
* Total actually deposited by all the coins.
*/
struct TALER_Amount deposit_total;
/**
* Our current time.
*/
struct GNUNET_TIME_Timestamp exchange_timestamp;
/**
* Merge key for the purse.
*/
struct TALER_PurseMergePublicKeyP merge_pub;
/**
* Encrypted contract of for the purse.
*/
struct TALER_EncryptedContract econtract;
/**
* Signature of the client affiming this request.
*/
struct TALER_PurseContractSignatureP purse_sig;
/**
* Fundamental details about the purse.
*/
struct TEH_PurseDetails pd;
/**
* Array of coins being deposited.
*/
struct TEH_PurseDepositedCoin *coins;
/**
* Length of the @e coins array.
*/
unsigned int num_coins;
/**
* Minimum age for deposits into this purse.
*/
uint32_t min_age;
/**
* Do we have an @e econtract?
*/
bool no_econtract;
};
/**
* Execute database transaction for /purses/$PID/create. 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 PurseCreateContext`
* @param connection MHD request context
* @param[out] mhd_ret set to MHD status on error
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
create_transaction (void *cls,
struct MHD_Connection *connection,
MHD_RESULT *mhd_ret)
{
struct PurseCreateContext *pcc = cls;
enum GNUNET_DB_QueryStatus qs;
struct TALER_Amount purse_fee;
bool in_conflict = true;
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (TEH_currency,
&purse_fee));
/* 1) create purse */
qs = TEH_plugin->insert_purse_request (
TEH_plugin->cls,
&pcc->pd.purse_pub,
&pcc->merge_pub,
pcc->pd.purse_expiration,
&pcc->pd.h_contract_terms,
pcc->min_age,
TALER_WAMF_MODE_MERGE_FULLY_PAID_PURSE,
&purse_fee,
&pcc->pd.target_amount,
&pcc->purse_sig,
&in_conflict);
if (qs < 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
TALER_LOG_WARNING (
"Failed to store create purse information in database\n");
*mhd_ret =
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"purse create");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (in_conflict)
{
struct TALER_PurseMergePublicKeyP merge_pub;
struct GNUNET_TIME_Timestamp purse_expiration;
struct TALER_PrivateContractHashP h_contract_terms;
struct TALER_Amount target_amount;
struct TALER_Amount balance;
struct TALER_PurseContractSignatureP purse_sig;
uint32_t min_age;
TEH_plugin->rollback (TEH_plugin->cls);
qs = TEH_plugin->get_purse_request (TEH_plugin->cls,
&pcc->pd.purse_pub,
&merge_pub,
&purse_expiration,
&h_contract_terms,
&min_age,
&target_amount,
&balance,
&purse_sig);
if (qs < 0)
{
GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs);
TALER_LOG_WARNING ("Failed to fetch purse information from database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select purse request");
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_CREATE_CONFLICTING_META_DATA),
TALER_JSON_pack_amount ("amount",
&target_amount),
GNUNET_JSON_pack_uint64 ("min_age",
min_age),
GNUNET_JSON_pack_timestamp ("purse_expiration",
purse_expiration),
GNUNET_JSON_pack_data_auto ("purse_sig",
&purse_sig),
GNUNET_JSON_pack_data_auto ("h_contract_terms",
&h_contract_terms),
GNUNET_JSON_pack_data_auto ("merge_pub",
&merge_pub));
return GNUNET_DB_STATUS_HARD_ERROR;
}
/* 2) deposit all coins */
for (unsigned int i = 0; inum_coins; i++)
{
struct TEH_PurseDepositedCoin *coin = &pcc->coins[i];
bool balance_ok = false;
bool conflict = true;
bool too_late = true;
qs = TEH_make_coin_known (&coin->cpi,
connection,
&coin->known_coin_id,
mhd_ret);
if (qs < 0)
return qs;
qs = TEH_plugin->do_purse_deposit (TEH_plugin->cls,
&pcc->pd.purse_pub,
&coin->cpi.coin_pub,
&coin->amount,
&coin->coin_sig,
&coin->amount_minus_fee,
&balance_ok,
&too_late,
&conflict);
if (qs <= 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
GNUNET_break (0 != 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,
"purse create deposit");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (! balance_ok)
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"Coin %s has insufficient balance for purse deposit of amount %s\n",
TALER_B2S (&coin->cpi.coin_pub),
TALER_amount2s (&coin->amount));
*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 (too_late)
{
*mhd_ret
= TALER_MHD_reply_with_ec (
connection,
TALER_EC_GENERIC_INTERNAL_INVARIANT_FAILURE,
"too late to deposit on purse creation");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (conflict)
{
struct TALER_Amount amount;
struct TALER_CoinSpendPublicKeyP coin_pub;
struct TALER_CoinSpendSignatureP coin_sig;
struct TALER_DenominationHashP h_denom_pub;
struct TALER_AgeCommitmentHash phac;
char *partner_url = NULL;
TEH_plugin->rollback (TEH_plugin->cls);
qs = TEH_plugin->get_purse_deposit (TEH_plugin->cls,
&pcc->pd.purse_pub,
&coin->cpi.coin_pub,
&amount,
&h_denom_pub,
&phac,
&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_data_auto ("h_denom_pub",
&h_denom_pub),
GNUNET_JSON_pack_data_auto ("h_age_restrictions",
&phac),
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;
}
}
/* 3) if present, persist contract */
if (! pcc->no_econtract)
{
in_conflict = true;
qs = TEH_plugin->insert_contract (TEH_plugin->cls,
&pcc->pd.purse_pub,
&pcc->econtract,
&in_conflict);
if (qs < 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
TALER_LOG_WARNING ("Failed to store purse information in database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"purse create contract");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (in_conflict)
{
struct TALER_EncryptedContract econtract;
struct GNUNET_HashCode h_econtract;
qs = TEH_plugin->select_contract_by_purse (
TEH_plugin->cls,
&pcc->pd.purse_pub,
&econtract);
if (qs <= 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
GNUNET_break (0 != qs);
TALER_LOG_WARNING (
"Failed to store fetch contract information from database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select contract");
return GNUNET_DB_STATUS_HARD_ERROR;
}
GNUNET_CRYPTO_hash (econtract.econtract,
econtract.econtract_size,
&h_econtract);
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_CONFLICT,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_PURSE_ECONTRACT_CONFLICTING_META_DATA),
GNUNET_JSON_pack_data_auto ("h_econtract",
&h_econtract),
GNUNET_JSON_pack_data_auto ("econtract_sig",
&econtract.econtract_sig),
GNUNET_JSON_pack_data_auto ("contract_pub",
&econtract.contract_pub));
GNUNET_free (econtract.econtract);
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 PurseCreateContext *pcc,
struct TEH_PurseDepositedCoin *coin,
const json_t *jcoin)
{
enum GNUNET_GenericReturnValue iret;
if (GNUNET_OK !=
(iret = TEH_common_purse_deposit_parse_coin (connection,
coin,
jcoin)))
return iret;
if (GNUNET_OK !=
(iret = TEH_common_deposit_check_purse_deposit (
connection,
coin,
&pcc->pd.purse_pub,
pcc->min_age)))
return iret;
if (0 >
TALER_amount_add (&pcc->deposit_total,
&pcc->deposit_total,
&coin->amount_minus_fee))
{
GNUNET_break (0);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_FAILED_COMPUTE_AMOUNT,
"total deposit contribution"))
? GNUNET_NO
: GNUNET_SYSERR;
}
return GNUNET_OK;
}
MHD_RESULT
TEH_handler_purses_create (
struct MHD_Connection *connection,
const struct TALER_PurseContractPublicKeyP *purse_pub,
const json_t *root)
{
struct PurseCreateContext pcc = {
.pd.purse_pub = *purse_pub,
.exchange_timestamp = GNUNET_TIME_timestamp_get ()
};
const json_t *deposits;
json_t *deposit;
unsigned int idx;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount ("amount",
TEH_currency,
&pcc.pd.target_amount),
GNUNET_JSON_spec_uint32 ("min_age",
&pcc.min_age),
GNUNET_JSON_spec_mark_optional (
TALER_JSON_spec_econtract ("econtract",
&pcc.econtract),
&pcc.no_econtract),
GNUNET_JSON_spec_fixed_auto ("merge_pub",
&pcc.merge_pub),
GNUNET_JSON_spec_fixed_auto ("purse_sig",
&pcc.purse_sig),
GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
&pcc.pd.h_contract_terms),
GNUNET_JSON_spec_array_const ("deposits",
&deposits),
GNUNET_JSON_spec_timestamp ("purse_expiration",
&pcc.pd.purse_expiration),
GNUNET_JSON_spec_end ()
};
const struct TEH_GlobalFee *gf;
{
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));
if (GNUNET_TIME_timestamp_cmp (pcc.pd.purse_expiration,
<,
pcc.exchange_timestamp))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_PURSE_CREATE_EXPIRATION_BEFORE_NOW,
NULL);
}
if (GNUNET_TIME_absolute_is_never (pcc.pd.purse_expiration.abs_time))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_PURSE_CREATE_EXPIRATION_IS_NEVER,
NULL);
}
pcc.num_coins = json_array_size (deposits);
if ( (0 == pcc.num_coins) ||
(pcc.num_coins > TALER_MAX_FRESH_COINS) )
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
"deposits");
}
{
struct TEH_KeyStateHandle *keys;
keys = TEH_keys_get_state ();
if (NULL == keys)
{
GNUNET_break (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_GENERIC_KEYS_MISSING,
NULL);
}
gf = TEH_keys_global_fee_by_time (keys,
pcc.exchange_timestamp);
}
if (NULL == gf)
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"Cannot create purse: global fees not configured!\n");
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_GENERIC_GLOBAL_FEES_MISSING,
NULL);
}
/* parse deposits */
pcc.coins = GNUNET_new_array (pcc.num_coins,
struct TEH_PurseDepositedCoin);
json_array_foreach (deposits, idx, deposit)
{
enum GNUNET_GenericReturnValue res;
struct TEH_PurseDepositedCoin *coin = &pcc.coins[idx];
res = parse_coin (connection,
&pcc,
coin,
deposit);
if (GNUNET_OK != res)
{
for (unsigned int i = 0; ifees.purse,
&pcc.deposit_total))
{
GNUNET_break_op (0);
GNUNET_free (pcc.coins);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_CREATE_PURSE_NEGATIVE_VALUE_AFTER_FEE,
NULL);
}
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
if (GNUNET_OK !=
TALER_wallet_purse_create_verify (
pcc.pd.purse_expiration,
&pcc.pd.h_contract_terms,
&pcc.merge_pub,
pcc.min_age,
&pcc.pd.target_amount,
&pcc.pd.purse_pub,
&pcc.purse_sig))
{
TALER_LOG_WARNING ("Invalid signature on /purses/$PID/create request\n");
for (unsigned int i = 0; ipreflight (TEH_plugin->cls))
{
GNUNET_break (0);
for (unsigned int i = 0; i