diff options
Diffstat (limited to 'src/exchangedb/exchange_do_melt.sql')
| -rw-r--r-- | src/exchangedb/exchange_do_melt.sql | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/src/exchangedb/exchange_do_melt.sql b/src/exchangedb/exchange_do_melt.sql new file mode 100644 index 000000000..0200986fa --- /dev/null +++ b/src/exchangedb/exchange_do_melt.sql @@ -0,0 +1,182 @@ +-- +-- This file is part of TALER +-- Copyright (C) 2014--2022 Taler Systems SA +-- +-- TALER is free software; you can redistribute it and/or modify it under the +-- terms of the GNU 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 General Public License for more details. +-- +-- You should have received a copy of the GNU General Public License along with +-- TALER; see the file COPYING. If not, see <http://www.gnu.org/licenses/> +-- + + + + +CREATE OR REPLACE FUNCTION exchange_do_melt( + IN in_cs_rms BYTEA, + IN in_amount_with_fee taler_amount, + IN in_rc BYTEA, + IN in_old_coin_pub BYTEA, + IN in_old_coin_sig BYTEA, + IN in_known_coin_id INT8, -- not used, but that's OK + IN in_noreveal_index INT4, + IN in_zombie_required BOOLEAN, + OUT out_balance_ok BOOLEAN, + OUT out_zombie_bad BOOLEAN, + OUT out_noreveal_index INT4) +LANGUAGE plpgsql +AS $$ +DECLARE + denom_max INT8; +BEGIN +-- Shards: INSERT refresh_commitments (by rc) +-- (rare:) SELECT refresh_commitments (by old_coin_pub) -- crosses shards! +-- (rare:) SEELCT refresh_revealed_coins (by melt_serial_id) +-- (rare:) PERFORM recoup_refresh (by rrc_serial) -- crosses shards! +-- UPDATE known_coins (by coin_pub) + +INSERT INTO exchange.refresh_commitments + (rc + ,old_coin_pub + ,old_coin_sig + ,amount_with_fee + ,noreveal_index + ) + VALUES + (in_rc + ,in_old_coin_pub + ,in_old_coin_sig + ,in_amount_with_fee + ,in_noreveal_index) + ON CONFLICT DO NOTHING; + +IF NOT FOUND +THEN + -- Idempotency check: see if an identical record exists. + out_noreveal_index=-1; + SELECT + noreveal_index + INTO + out_noreveal_index + FROM exchange.refresh_commitments + WHERE rc=in_rc; + out_balance_ok=FOUND; + out_zombie_bad=FALSE; -- zombie is OK + RETURN; +END IF; + + +IF in_zombie_required +THEN + -- Check if this coin was part of a refresh + -- operation that was subsequently involved + -- in a recoup operation. We begin by all + -- refresh operations our coin was involved + -- with, then find all associated reveal + -- operations, and then see if any of these + -- reveal operations was involved in a recoup. + PERFORM + FROM recoup_refresh + WHERE rrc_serial IN + (SELECT rrc_serial + FROM refresh_revealed_coins + WHERE melt_serial_id IN + (SELECT melt_serial_id + FROM refresh_commitments + WHERE old_coin_pub=in_old_coin_pub)); + IF NOT FOUND + THEN + out_zombie_bad=TRUE; + out_balance_ok=FALSE; + RETURN; + END IF; +END IF; + +out_zombie_bad=FALSE; -- zombie is OK + + +-- Check and update balance of the coin. +UPDATE known_coins kc + SET + remaining.frac=(kc.remaining).frac-in_amount_with_fee.frac + + CASE + WHEN (kc.remaining).frac < in_amount_with_fee.frac + THEN 100000000 + ELSE 0 + END, + remaining.val=(kc.remaining).val-in_amount_with_fee.val + - CASE + WHEN (kc.remaining).frac < in_amount_with_fee.frac + THEN 1 + ELSE 0 + END + WHERE coin_pub=in_old_coin_pub + AND ( ((kc.remaining).val > in_amount_with_fee.val) OR + ( ((kc.remaining).frac >= in_amount_with_fee.frac) AND + ((kc.remaining).val >= in_amount_with_fee.val) ) ); + +IF NOT FOUND +THEN + -- Insufficient balance. + out_noreveal_index=-1; + out_balance_ok=FALSE; + RETURN; +END IF; + + + +-- Special actions needed for a CS melt? +IF NOT NULL in_cs_rms +THEN + -- Get maximum denominations serial value in + -- existence, this will determine how long the + -- nonce will be locked. + SELECT + denominations_serial + INTO + denom_max + FROM exchange.denominations + ORDER BY denominations_serial DESC + LIMIT 1; + + -- Cache CS signature to prevent replays in the future + -- (and check if cached signature exists at the same time). + INSERT INTO exchange.cs_nonce_locks + (nonce + ,max_denomination_serial + ,op_hash) + VALUES + (cs_rms + ,denom_serial + ,in_rc) + ON CONFLICT DO NOTHING; + + IF NOT FOUND + THEN + -- Record exists, make sure it is the same + SELECT 1 + FROM exchange.cs_nonce_locks + WHERE nonce=cs_rms + AND op_hash=in_rc; + + IF NOT FOUND + THEN + -- Nonce reuse detected + out_balance_ok=FALSE; + out_zombie_bad=FALSE; + out_noreveal_index=42; -- FIXME: return error message more nicely! + ASSERT false, 'nonce reuse attempted by client'; + END IF; + END IF; +END IF; + +-- Everything fine, return success! +out_balance_ok=TRUE; +out_noreveal_index=in_noreveal_index; + +END $$; |