diff options
| -rw-r--r-- | src/exchange/taler-exchange-httpd_db.c | 110 | ||||
| -rw-r--r-- | src/exchange/taler-exchange-httpd_db.h | 3 | ||||
| -rw-r--r-- | src/exchangedb/exchange-0001.sql | 188 | ||||
| -rw-r--r-- | src/exchangedb/plugin_exchangedb_postgres.c | 59 | ||||
| -rw-r--r-- | src/include/taler_exchangedb_plugin.h | 25 |
5 files changed, 367 insertions, 18 deletions
diff --git a/src/exchange/taler-exchange-httpd_db.c b/src/exchange/taler-exchange-httpd_db.c index 7ced8b88e..388679c38 100644 --- a/src/exchange/taler-exchange-httpd_db.c +++ b/src/exchange/taler-exchange-httpd_db.c @@ -164,14 +164,29 @@ TEH_make_coin_known (const struct TALER_CoinPublicInfo *coin, } -enum GNUNET_DB_QueryStatus -TEH_check_coin_balance (struct MHD_Connection *connection, - const struct TALER_CoinSpendPublicKeyP *coin_pub, - const struct TALER_Amount *coin_value, - const struct TALER_Amount *op_cost, - bool check_recoup, - bool zombie_required, - MHD_RESULT *mhd_ret) +/** + * Called when we actually know that the balance (was) insufficient. + * Re-does the check (slowly) to compute the full error message for + * the client. + * + * @param connection HTTP connection to report hard errors on + * @param coin_pub coin to analyze + * @param coin_value total value of the original coin (by denomination) + * @param op_cost cost of the current operation (for error reporting) + * @param check_recoup should we include recoup transactions in the check + * @param zombie_required additional requirement that the coin must + * be a zombie coin, or also hard failure + * @param[out] mhd_ret set to response status code, on hard error only + * @return transaction status + */ +static enum GNUNET_DB_QueryStatus +check_coin_balance (struct MHD_Connection *connection, + const struct TALER_CoinSpendPublicKeyP *coin_pub, + const struct TALER_Amount *coin_value, + const struct TALER_Amount *op_cost, + bool check_recoup, + bool zombie_required, + MHD_RESULT *mhd_ret) { struct TALER_EXCHANGEDB_TransactionList *tl; struct TALER_Amount spent; @@ -273,13 +288,90 @@ TEH_check_coin_balance (struct MHD_Connection *connection, return GNUNET_DB_STATUS_HARD_ERROR; } - /* we're good, coin has sufficient funds to be melted */ + /* This should not happen: The coin has sufficient funds + after all!?!? */ TEH_plugin->free_coin_transaction_list (TEH_plugin->cls, tl); return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT; } +enum GNUNET_DB_QueryStatus +TEH_check_coin_balance (struct MHD_Connection *connection, + const struct TALER_CoinSpendPublicKeyP *coin_pub, + const struct TALER_Amount *coin_value, + const struct TALER_Amount *op_cost, + bool check_recoup, + bool zombie_required, + MHD_RESULT *mhd_ret) +{ + bool balance_ok = false; + bool zombie_ok = false; + enum GNUNET_DB_QueryStatus qs; + + qs = TEH_plugin->do_check_coin_balance (TEH_plugin->cls, + coin_pub, + coin_value, + check_recoup, + zombie_required, + &balance_ok, + &zombie_ok); + switch (qs) + { + case GNUNET_DB_STATUS_HARD_ERROR: + *mhd_ret = TALER_MHD_reply_with_error ( + connection, + MHD_HTTP_INTERNAL_SERVER_ERROR, + TALER_EC_GENERIC_DB_FETCH_FAILED, + "check_coin_balance"); + return qs; + case GNUNET_DB_STATUS_SOFT_ERROR: + return qs; + case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS: + GNUNET_break (0); + *mhd_ret = TALER_MHD_reply_with_error ( + connection, + MHD_HTTP_INTERNAL_SERVER_ERROR, + TALER_EC_GENERIC_DB_FETCH_FAILED, + "check_coin_balance"); + return GNUNET_DB_STATUS_HARD_ERROR; + case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT: + /* handled below */ + break; + } + if (! zombie_ok) + { + GNUNET_break_op (0); + *mhd_ret = TALER_MHD_reply_with_error ( + connection, + MHD_HTTP_BAD_REQUEST, + TALER_EC_EXCHANGE_MELT_COIN_EXPIRED_NO_ZOMBIE, + NULL); + return GNUNET_DB_STATUS_HARD_ERROR; + } + if (balance_ok) + return qs; + /* balance is not OK, do expensive call to compute full error message */ + qs = check_coin_balance (connection, + coin_pub, + coin_value, + op_cost, + check_recoup, + zombie_required, + mhd_ret); + if (qs < 0) + return qs; /* we expected to fail (same check as before!) */ + GNUNET_break (0); /* stored procedure and individual statements + disagree, should be impossible! */ + *mhd_ret = TALER_MHD_reply_with_error ( + connection, + MHD_HTTP_INTERNAL_SERVER_ERROR, + TALER_EC_GENERIC_DB_INVARIANT_FAILURE, + "stored procedure disagrees with full coin transaction history fetch"); + return GNUNET_DB_STATUS_HARD_ERROR; +} + + enum GNUNET_GenericReturnValue TEH_DB_run_transaction (struct MHD_Connection *connection, const char *name, diff --git a/src/exchange/taler-exchange-httpd_db.h b/src/exchange/taler-exchange-httpd_db.h index 60885dbd1..5ee3b41d5 100644 --- a/src/exchange/taler-exchange-httpd_db.h +++ b/src/exchange/taler-exchange-httpd_db.h @@ -47,6 +47,9 @@ TEH_make_coin_known (const struct TALER_CoinPublicInfo *coin, * insufficient for all transactions associated with the * coin, return a hard error. * + * We first do a "fast" check using a stored procedure, and + * only obtain the "full" data on failure (for performance). + * * @param connection HTTP connection to report hard errors on * @param coin_pub coin to analyze * @param coin_value total value of the original coin (by denomination) diff --git a/src/exchangedb/exchange-0001.sql b/src/exchangedb/exchange-0001.sql index dc6b2bba2..1725b70e0 100644 --- a/src/exchangedb/exchange-0001.sql +++ b/src/exchangedb/exchange-0001.sql @@ -899,6 +899,194 @@ COMMENT ON FUNCTION exchange_do_withdraw_limit_check(INT8, INT8, INT8, INT4) +CREATE OR REPLACE FUNCTION exchange_do_check_coin_balance( + IN denom_val INT8, -- value of the denomination of the coin + IN denom_frac INT4, -- value of the denomination of the coin + IN in_coin_pub BYTEA, -- coin public key + IN check_recoup BOOLEAN, -- do we need to check the recoup table? + IN zombie_required BOOLEAN, -- do we need a zombie coin? + OUT balance_ok BOOLEAN, -- balance satisfied? + OUT zombie_ok BOOLEAN) -- zombie satisfied? +LANGUAGE plpgsql +AS $$ +DECLARE + coin_uuid INT8; -- known_coin_id of coin_pub +DECLARE + tmp_val INT8; -- temporary result +DECLARE + tmp_frac INT8; -- temporary result +DECLARE + spent_val INT8; -- how much of coin was spent? +DECLARE + spent_frac INT8; -- how much of coin was spent? +DECLARE + unspent_val INT8; -- how much of coin was refunded? +DECLARE + unspent_frac INT8; -- how much of coin was refunded? +BEGIN + +-- Note: possible future optimization: get the coin_uuid from the previous +-- 'ensure_coin_known' and pass that here instead of the coin_pub. Might help +-- a tiny bit with performance. +SELECT known_coin_id INTO coin_uuid + FROM known_coins + WHERE coin_pub=in_coin_pub; + +IF NOT FOUND +THEN + -- coin unknown, should be impossible! + balance_ok=FALSE; + zombie_ok=FALSE; + ASSERT false, 'coin unknown'; + RETURN; +END IF; + + +spent_val = 0; +spent_frac = 0; +unspent_val = denom_val; +unspent_frac = denom_frac; + +SELECT + SUM(amount_with_fee_val) -- overflow here is not plausible + ,SUM(CAST(amount_with_fee_frac AS INT8)) -- compute using 64 bits + INTO + tmp_val + ,tmp_frac + FROM deposits + WHERE known_coin_id=coin_uuid; + +IF tmp_val IS NOT NULL +THEN + spent_val = spent_val + tmp_val; + spent_frac = spent_frac + tmp_frac; +END IF; + +SELECT + SUM(amount_with_fee_val) -- overflow here is not plausible + ,SUM(CAST(amount_with_fee_frac AS INT8)) -- compute using 64 bits + INTO + tmp_val + ,tmp_frac + FROM refresh_commitments + WHERE old_known_coin_id=coin_uuid; + +IF tmp_val IS NOT NULL +THEN + spent_val = spent_val + tmp_val; + spent_frac = spent_frac + tmp_frac; +END IF; + + +SELECT + SUM(rf.amount_with_fee_val) -- overflow here is not plausible + ,SUM(CAST(rf.amount_with_fee_frac AS INT8)) -- compute using 64 bits + INTO + tmp_val + ,tmp_frac + FROM deposits + JOIN refunds rf + USING (deposit_serial_id) + WHERE + known_coin_id=coin_uuid; +IF tmp_val IS NOT NULL +THEN + unspent_val = unspent_val + tmp_val; + unspent_frac = unspent_frac + tmp_frac; +END IF; + +-- Note: even if 'check_recoup' is true, the tables below +-- are in practice likely empty (as they only apply if +-- the exchange (ever) had to revoke keys). +IF check_recoup +THEN + + SELECT + SUM(amount_val) -- overflow here is not plausible + ,SUM(CAST(amount_frac AS INT8)) -- compute using 64 bits + INTO + tmp_val + ,tmp_frac + FROM recoup_refresh + WHERE known_coin_id=coin_uuid; + + IF tmp_val IS NOT NULL + THEN + spent_val = spent_val + tmp_val; + spent_frac = spent_frac + tmp_frac; + END IF; + + SELECT + SUM(amount_val) -- overflow here is not plausible + ,SUM(CAST(amount_frac AS INT8)) -- compute using 64 bits + INTO + tmp_val + ,tmp_frac + FROM recoup + WHERE known_coin_id=coin_uuid; + + IF tmp_val IS NOT NULL + THEN + spent_val = spent_val + tmp_val; + spent_frac = spent_frac + tmp_frac; + END IF; + + SELECT + SUM(amount_val) -- overflow here is not plausible + ,SUM(CAST(amount_frac AS INT8)) -- compute using 64 bits + INTO + tmp_val + ,tmp_frac + FROM recoup_refresh + JOIN refresh_revealed_coins rrc + USING (rrc_serial) + JOIN refresh_commitments rfc + ON (rrc.melt_serial_id = rfc.melt_serial_id) + WHERE rfc.old_known_coin_id=coin_uuid; + + IF tmp_val IS NOT NULL + THEN + unspent_val = unspent_val + tmp_val; + unspent_frac = unspent_frac + tmp_frac; + END IF; + + IF ( (0 < tmp_val) OR (0 < tmp_frac) ) + THEN + -- There was a transaction that justifies the zombie + -- status, clear the flag + zombie_required=FALSE; + END IF; + +END IF; + + +-- normalize results +spent_val = spent_val + spent_frac / 100000000; +spent_frac = spent_frac % 100000000; +unspent_val = unspent_val + unspent_frac / 100000000; +unspent_frac = unspent_frac % 100000000; + +-- Actually check if the coin balance is sufficient. Verbosely. ;-) +IF (unspent_val > spent_val) +THEN + balance_ok=TRUE; +ELSE + IF (unspent_val = spent_val) AND (unspent_frac >= spent_frac) + THEN + balance_ok=TRUE; + ELSE + balance_ok=FALSE; + END IF; +END IF; + +zombie_ok = NOT zombie_required; + +END $$; + +COMMENT ON FUNCTION exchange_do_check_coin_balance(INT8, INT4, BYTEA, BOOLEAN, BOOLEAN) + IS 'Checks whether the coin has sufficient balance for all the operations associated with it'; + + -- Complete transaction diff --git a/src/exchangedb/plugin_exchangedb_postgres.c b/src/exchangedb/plugin_exchangedb_postgres.c index 73a03e751..8e184a9dd 100644 --- a/src/exchangedb/plugin_exchangedb_postgres.c +++ b/src/exchangedb/plugin_exchangedb_postgres.c @@ -596,6 +596,16 @@ prepare_statements (struct PostgresClosure *pg) "lock_withdraw", "LOCK TABLE reserves_out;", 0), + /* Used in #postgres_do_check_coin_balance() to check + a coin's balance */ + GNUNET_PQ_make_prepare ( + "call_check_coin_balance", + "SELECT " + " balance_ok" + ",zombie_ok" + " FROM exchange_do_check_coin_balance" + " ($1,$2,$3,$4,$5);", + 5), /* Used in #postgres_do_withdraw() to store the signature of a blinded coin with the blinded coin's details before returning it during /reserve/withdraw. We store @@ -4492,6 +4502,53 @@ postgres_get_withdraw_info ( /** + * Check coin balance is sufficient to satisfy balance + * invariants. + * + * @param cls the `struct PostgresClosure` with the plugin-specific state + * @param coin_pub coin to check + * @param coin_value value of the coin's denomination (avoids internal lookup) + * @param check_recoup include recoup and recoup_refresh tables in calculation + * @param zombie_required additionally require coin to be a zombie coin + * @param[out] balance_ok set to true if the balance was sufficient + * @param[out] zombie_ok set to true if the zombie requirement was satisfied + * @return query execution status + */ +static enum GNUNET_DB_QueryStatus +postgres_do_check_coin_balance ( + void *cls, + const struct TALER_CoinSpendPublicKeyP *coin_pub, + const struct TALER_Amount *coin_value, + bool check_recoup, + bool zombie_required, + bool *balance_ok, + bool *zombie_ok) +{ + struct PostgresClosure *pg = cls; + struct GNUNET_PQ_QueryParam params[] = { + TALER_PQ_query_param_amount (coin_value), + GNUNET_PQ_query_param_auto_from_type (coin_pub), + GNUNET_PQ_query_param_bool (check_recoup), + GNUNET_PQ_query_param_bool (zombie_required), + GNUNET_PQ_query_param_end + }; + struct GNUNET_PQ_ResultSpec rs[] = { + GNUNET_PQ_result_spec_bool ("balance_ok", + balance_ok), + GNUNET_PQ_result_spec_bool ("zombie_ok", + zombie_ok), + GNUNET_PQ_result_spec_end + }; + + return GNUNET_PQ_eval_prepared_singleton_select (pg->conn, + "call_check_coin_balance", + params, + rs); + +} + + +/** * Perform withdraw operation, checking for sufficient balance * and possibly persisting the withdrawal details. * @@ -11825,7 +11882,7 @@ libtaler_plugin_exchangedb_postgres_init (void *cls) plugin->get_latest_reserve_in_reference = &postgres_get_latest_reserve_in_reference; plugin->get_withdraw_info = &postgres_get_withdraw_info; - // plugin->insert_withdraw_info = &postgres_insert_withdraw_info; + plugin->do_check_coin_balance = &postgres_do_check_coin_balance; plugin->do_withdraw = &postgres_do_withdraw; plugin->do_withdraw_limit_check = &postgres_do_withdraw_limit_check; plugin->get_reserve_history = &postgres_get_reserve_history; diff --git a/src/include/taler_exchangedb_plugin.h b/src/include/taler_exchangedb_plugin.h index fd2f3dc42..56a16dd72 100644 --- a/src/include/taler_exchangedb_plugin.h +++ b/src/include/taler_exchangedb_plugin.h @@ -2503,18 +2503,27 @@ struct TALER_EXCHANGEDB_Plugin /** - * Store collectable coin under the corresponding hash of the blinded - * message. + * Check coin balance is sufficient to satisfy balance + * invariants. * - * @param cls the @e cls of this struct with the plugin-specific state - * @param collectable corresponding collectable coin (blind signature) - * if a coin is found - * @return statement execution status + * @param cls the `struct PostgresClosure` with the plugin-specific state + * @param coin_pub coin to check + * @param coin_value value of the coin's denomination (avoids internal lookup) + * @param check_recoup include recoup and recoup_refresh tables in calculation + * @param zombie_required additionally require coin to be a zombie coin + * @param[out] balance_ok set to true if the balance was sufficient + * @param[out] zombie_ok set to true if the zombie requirement was satisfied + * @return query execution status */ enum GNUNET_DB_QueryStatus - (*insert_withdraw_infoXX)( + (*do_check_coin_balance)( void *cls, - const struct TALER_EXCHANGEDB_CollectableBlindcoin *collectable); + const struct TALER_CoinSpendPublicKeyP *coin_pub, + const struct TALER_Amount *coin_value, + bool check_recoup, + bool zombie_required, + bool *balance_ok, + bool *zombie_ok); /** |