cp sql/ from GNU Taler exchange

include/sql/exchange_do_refresh.sql

@@ -0,0 +1,206 @@
+--
+-- This file is part of TALER
+-- Copyright (C) 2025 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/>
+--
+-- @author Özgür Kesim
+
+DROP FUNCTION IF EXISTS exchange_do_refresh;
+
+CREATE FUNCTION exchange_do_refresh(
+  IN in_rc BYTEA,
+  IN in_now INT8,
+  IN in_refresh_seed BYTEA,
+  IN in_planchets_h BYTEA,
+  IN in_amount_with_fee taler_amount,
+  IN in_blinding_seed BYTEA,
+  IN in_cs_r_values BYTEA[],
+  IN in_cs_r_choices INT8,
+  IN in_selected_h BYTEA,
+  IN in_denom_sigs BYTEA[],
+  IN in_denom_serials INT8[],
+  IN in_old_coin_pub BYTEA,
+  IN in_old_coin_sig BYTEA,
+  IN in_noreveal_index INT4,
+  IN in_zombie_required BOOLEAN,
+  OUT out_coin_found BOOLEAN,
+  OUT out_balance_ok BOOLEAN,
+  OUT out_zombie_bad BOOLEAN,
+  OUT out_nonce_reuse BOOLEAN,
+  OUT out_idempotent BOOLEAN,
+  OUT out_noreveal_index INT4,
+  OUT out_coin_balance taler_amount)
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  known_coin RECORD;
+  difference RECORD;
+BEGIN
+-- Shards: INSERT refresh (by rc)
+-- (rare:) SELECT refresh (by old_coin_pub) -- crosses shards!
+-- (rare:) SELECT refresh_revealed_coins (by refresh_id)
+-- (rare:) PERFORM recoup_refresh (by rrc_serial) -- crosses shards!
+--         UPDATE known_coins (by coin_pub)
+
+-- First, find old coin
+SELECT known_coin_id
+     ,remaining
+  INTO known_coin
+  FROM known_coins
+  WHERE coin_pub = in_old_coin_pub;
+
+IF NOT FOUND
+THEN
+  out_coin_found = FALSE;
+  out_balance_ok = TRUE;
+  out_zombie_bad = FALSE;
+  out_nonce_reuse = FALSE;
+  out_idempotent = FALSE;
+  out_noreveal_index = -1 ;
+  out_coin_balance.val = 0;
+  out_coin_balance.frac = 0;
+  RETURN;
+END IF;
+
+out_coin_found = TRUE;
+out_coin_balance = known_coin.remaining;
+
+-- Next, check for idempotency
+SELECT TRUE, noreveal_index
+INTO out_idempotent, out_noreveal_index
+FROM exchange.refresh
+WHERE rc=in_rc;
+
+IF out_idempotent
+THEN
+  -- out_idempotent is set
+  -- out_noreveal_index is set
+  -- out_coin_found is set
+  -- out_coin_balance is set
+  out_balance_ok = TRUE;
+  out_zombie_bad = FALSE; -- zombie is OK
+  out_nonce_reuse = FALSE;
+RETURN;
+END IF;
+
+out_idempotent = FALSE;
+out_noreveal_index = in_noreveal_index;
+
+-- Ensure the uniqueness of the blinding_seed
+IF in_blinding_seed IS NOT NULL
+THEN
+  INSERT INTO unique_refresh_blinding_seed
+    (blinding_seed)
+  VALUES
+    (in_blinding_seed)
+  ON CONFLICT DO NOTHING;
+
+  IF NOT FOUND
+  THEN
+      out_nonce_reuse = TRUE;
+      out_balance_ok = TRUE;
+      out_zombie_bad = FALSE; -- zombie is OK
+      RETURN;
+  END IF;
+END IF;
+
+out_nonce_reuse = FALSE;
+
+INSERT INTO exchange.refresh
+  (rc
+  ,execution_date
+  ,old_coin_pub
+  ,old_coin_sig
+  ,planchets_h
+  ,amount_with_fee
+  ,noreveal_index
+  ,refresh_seed
+  ,blinding_seed
+  ,cs_r_values
+  ,cs_r_choices
+  ,selected_h
+  ,denom_sigs
+  ,denom_serials
+  )
+  VALUES
+  (in_rc
+  ,in_now
+  ,in_old_coin_pub
+  ,in_old_coin_sig
+  ,in_planchets_h
+  ,in_amount_with_fee
+  ,in_noreveal_index
+  ,in_refresh_seed
+  ,in_blinding_seed
+  ,in_cs_r_values
+  ,in_cs_r_choices
+  ,in_selected_h
+  ,in_denom_sigs
+  ,in_denom_serials
+  )
+  ON CONFLICT DO NOTHING;
+
+IF NOT FOUND
+THEN
+  RAISE EXCEPTION 'Conflict in refresh despite idempotency check for rc(%)!', rc;
+  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 refresh_id IN
+      (SELECT refresh_id
+       FROM refresh
+       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 coin balance is sufficient.
+SELECT *
+INTO difference
+FROM amount_left_minus_right(out_coin_balance
+                            ,in_amount_with_fee);
+
+out_balance_ok = difference.ok;
+
+IF NOT out_balance_ok
+THEN
+  RETURN;
+END IF;
+
+out_coin_balance = difference.diff;
+
+-- Check and update balance of the coin.
+UPDATE known_coins
+  SET
+    remaining = out_coin_balance
+  WHERE
+    known_coin_id = known_coin.known_coin_id;
+
+END $$;