diff options
Diffstat (limited to 'src/exchange/taler-exchange-httpd_purses_deposit.c')
| -rw-r--r-- | src/exchange/taler-exchange-httpd_purses_deposit.c | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/src/exchange/taler-exchange-httpd_purses_deposit.c b/src/exchange/taler-exchange-httpd_purses_deposit.c new file mode 100644 index 000000000..8e4d5e41a --- /dev/null +++ b/src/exchange/taler-exchange-httpd_purses_deposit.c @@ -0,0 +1,507 @@ +/* + 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 <http://www.gnu.org/licenses/> +*/ +/** + * @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 <gnunet/gnunet_util_lib.h> +#include <gnunet/gnunet_json_lib.h> +#include <jansson.h> +#include <microhttpd.h> +#include "taler_dbevents.h" +#include "taler_json_lib.h" +#include "taler_mhd_lib.h" +#include "taler-exchange-httpd_common_deposit.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" + + +/** + * 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 TEH_PurseDepositedCoin *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; i<pcc->num_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->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, + "do purse deposit"); + return GNUNET_DB_STATUS_HARD_ERROR; + } + 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 (too_late) + { + TEH_plugin->rollback (TEH_plugin->cls); + *mhd_ret + = TALER_MHD_reply_with_ec ( + connection, + TALER_EC_EXCHANGE_PURSE_DEPOSIT_DECIDED_ALREADY, + NULL); + 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->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 ("h_denom_pub", + &h_denom_pub), + GNUNET_JSON_pack_data_auto ("h_age_commitment", + &phac), + 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 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->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 TALER_MHD_reply_with_error (connection, + MHD_HTTP_INTERNAL_SERVER_ERROR, + TALER_EC_GENERIC_FAILED_COMPUTE_AMOUNT, + "total deposit contribution"); + } + 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 () + }; + const json_t *deposits; + json_t *deposit; + unsigned int idx; + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_array_const ("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); + 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 create_timestamp; + struct GNUNET_TIME_Timestamp merge_timestamp; + bool was_deleted; + bool was_refunded; + + qs = TEH_plugin->select_purse ( + TEH_plugin->cls, + pcc.purse_pub, + &create_timestamp, + &pcc.purse_expiration, + &pcc.amount, + &pcc.deposit_total, + &pcc.h_contract_terms, + &merge_timestamp, + &was_deleted, + &was_refunded); + 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 (was_refunded || + was_deleted) + { + return TALER_MHD_reply_with_error ( + connection, + MHD_HTTP_GONE, + was_deleted + ? TALER_EC_EXCHANGE_GENERIC_PURSE_DELETED + : TALER_EC_EXCHANGE_GENERIC_PURSE_EXPIRED, + GNUNET_TIME_timestamp2s (pcc.purse_expiration)); + } + } + + /* 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; i<idx; i++) + TEH_common_purse_deposit_free_coin (&pcc.coins[i]); + GNUNET_free (pcc.coins); + return (GNUNET_NO == res) ? MHD_YES : MHD_NO; + } + } + + if (GNUNET_SYSERR == + TEH_plugin->preflight (TEH_plugin->cls)) + { + GNUNET_break (0); + for (unsigned int i = 0; i<pcc.num_coins; i++) + TEH_common_purse_deposit_free_coin (&pcc.coins[i]); + 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)) + { + for (unsigned int i = 0; i<pcc.num_coins; i++) + TEH_common_purse_deposit_free_coin (&pcc.coins[i]); + 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); + for (unsigned int i = 0; i<pcc.num_coins; i++) + TEH_common_purse_deposit_free_coin (&pcc.coins[i]); + GNUNET_free (pcc.coins); + return res; + } +} + + +/* end of taler-exchange-httpd_purses_deposit.c */ |