exchange

commit b82a40e73234024746e2672e36d706db41437087
parent a82c5bc795cdfb500bf00cceb6515770df02cb24
Author: Özgür Kesim <oec@codeblau.de>
Date:   Wed,  7 May 2025 09:40:30 +0200

[exchangedb] fix idempotency check logic for withdraw

In case of a withdraw _without_ age-restriction, the field
noreveal_index is NULL.  Therefore, in an idempotency scenario,
the returned out_noreveal_index might be NULL.  We now
accept a NULL return value for that in the handler.

Diffstat:
M
src/exchangedb/exchange_do_withdraw.sql
 | 
6
++----
M
src/exchangedb/pg_do_withdraw.c
 | 
10
++++++++--

2 files changed, 10 insertions(+), 6 deletions(-)
diff --git a/src/exchangedb/exchange_do_withdraw.sql b/src/exchangedb/exchange_do_withdraw.sql
@@ -37,7 +37,7 @@ CREATE FUNCTION exchange_do_withdraw(
   OUT out_required_age INT2, -- in years ϵ [0,1..)
   OUT out_reserve_birthday INT4,
   OUT out_idempotent BOOLEAN,
-  OUT out_noreveal_index INT2,
+  OUT out_noreveal_index INT2, -- possibly NULL (if not age-withdraw)
   OUT out_nonce_reuse BOOLEAN)
 LANGUAGE plpgsql
 AS $$
@@ -49,9 +49,7 @@ DECLARE
   my_earliest_date DATE;
 BEGIN
 -- Shards: reserves by reserve_pub (SELECT)
---         reserves_out (INSERT, with CONFLICT detection) by wih
 --         reserves by reserve_pub (UPDATE)
---         reserves_in by reserve_pub (SELECT)
 
 -- First, find the reserve
 SELECT current_balance
@@ -90,7 +88,7 @@ out_idempotent = FOUND;
 
 IF out_idempotent
 THEN
-  -- out_idempotent, out_noreveal_index are set, report.
+  -- out_idempotent set, out_noreveal_index possibly set, report.
   out_balance_ok = TRUE;
   out_age_ok = TRUE;
   out_required_age = -1;
diff --git a/src/exchangedb/pg_do_withdraw.c b/src/exchangedb/pg_do_withdraw.c
@@ -81,6 +81,7 @@ TEH_PG_do_withdraw (
     GNUNET_PQ_query_param_end
   };
   bool reserve_found;
+  bool no_noreveal_index;
   struct GNUNET_PQ_ResultSpec rs[] = {
     GNUNET_PQ_result_spec_bool ("out_reserve_found",
                                 &reserve_found),
@@ -96,8 +97,10 @@ TEH_PG_do_withdraw (
                                   reserve_birthday),
     GNUNET_PQ_result_spec_bool ("out_idempotent",
                                 idempotent),
-    GNUNET_PQ_result_spec_uint16 ("out_noreveal_index",
-                                  noreveal_index),
+    GNUNET_PQ_result_spec_allow_null (
+      GNUNET_PQ_result_spec_uint16 ("out_noreveal_index",
+                                    noreveal_index),
+      &no_noreveal_index),
     GNUNET_PQ_result_spec_bool ("out_nonce_reuse",
                                 nonce_reuse),
     GNUNET_PQ_result_spec_end
@@ -134,5 +137,8 @@ TEH_PG_do_withdraw (
     return qs;
   if (! reserve_found)
     return GNUNET_DB_STATUS_SUCCESS_NO_RESULTS;
+  if ((withdraw->age_proof_required) &&
+      (idempotent && no_noreveal_index))
+    GNUNET_break (0);
   return qs;
 }