actually rely upon taler-merchant-exchangekeyupdate in taler-merchant-httpd

4 files changed, 146 insertions, 568 deletions

diff --git a/src/backend/taler-merchant-exchangekeyupdate.c b/src/backend/taler-merchant-exchangekeyupdate.c
index 4790953a..07d01d11 100644
--- a/src/backend/taler-merchant-exchangekeyupdate.c
+++ b/src/backend/taler-merchant-exchangekeyupdate.c
@@ -494,10 +494,6 @@ cert_cb (
   struct GNUNET_TIME_Absolute n;
 
   e->conn = NULL;
-  /* limit retry */
-  e->first_retry
-    = GNUNET_TIME_relative_to_absolute (
-        EXCHANGE_MAXFREQ);
   switch (kr->hr.http_status)
   {
   case MHD_HTTP_OK:
@@ -526,6 +522,10 @@ cert_cb (
     e->keys = TALER_EXCHANGE_keys_incref (keys);
     /* Reset back-off */
     e->retry_delay = EXCHANGE_MAXFREQ;
+    /* limit retry */
+    e->first_retry
+      = GNUNET_TIME_relative_to_absolute (
+          EXCHANGE_MAXFREQ);
     /* Limit by expiration */
     n = GNUNET_TIME_absolute_max (e->first_retry,
                                   keys->key_data_expiration.abs_time);
diff --git a/src/backend/taler-merchant-httpd_exchanges.c b/src/backend/taler-merchant-httpd_exchanges.c
index 6bcbd5c8..d1397870 100644
--- a/src/backend/taler-merchant-httpd_exchanges.c
+++ b/src/backend/taler-merchant-httpd_exchanges.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  (C) 2014-2023 Taler Systems SA
+  (C) 2014-2024 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
@@ -243,12 +243,7 @@ struct TMH_Exchange
   char *currency;
 
   /**
-   * A connection to this exchange
-   */
-  struct TALER_EXCHANGE_GetKeysHandle *conn;
-
-  /**
-   * The keys of this exchange
+   * The keys of this exchange.
    */
   struct TALER_EXCHANGE_Keys *keys;
 
@@ -263,70 +258,24 @@ struct TMH_Exchange
   struct FeesByWireMethod *wire_fees_tail;
 
   /**
-   * Master public key of the exchange.
+   * Task to retry downloading /keys again.
    */
-  struct TALER_MasterPublicKeyP master_pub;
+  struct GNUNET_SCHEDULER_Task *retry_task;
 
   /**
-   * How soon can may we, at the earliest, re-download /keys?
+   * When are we willing to force downloading again?
    */
   struct GNUNET_TIME_Absolute first_retry;
 
   /**
-   * How long should we wait between the next retry?
+   * Current exponential back-off for @e retry_task.
    */
   struct GNUNET_TIME_Relative retry_delay;
 
   /**
-   * How long should we wait between the next retry for /wire?
-   */
-  struct GNUNET_TIME_Relative wire_retry_delay;
-
-  /**
-   * Task where we retry fetching /keys from the exchange.
-   */
-  struct GNUNET_SCHEDULER_Task *retry_task;
-
-  /**
-   * What state is this exchange in?
+   * Master public key of the exchange.
    */
-  enum
-  {
-
-    /**
-     * Downloading /keys failed.
-     */
-    ESTATE_FAILED = -1,
-
-    /**
-     * Nothing was ever done.
-     */
-    ESTATE_INIT = 0,
-
-    /**
-     * We are actively downloading /keys for the first time.
-     */
-    ESTATE_DOWNLOADING_FIRST = 1,
-
-    /**
-     * We finished downloading /keys and the exchange is
-     * ready.
-     */
-    ESTATE_DOWNLOADED = 2,
-
-    /**
-     * We are downloading /keys again after a previous
-     * success.
-     */
-    ESTATE_REDOWNLOADING_SUCCESS = 3,
-
-    /**
-     * We are downloading /keys again after a previous
-     * failure.
-     */
-    ESTATE_REDOWNLOADING_FAILURE = 4
-
-  } state;
+  struct TALER_MasterPublicKeyP master_pub;
 
   /**
    * true if this exchange is from our configuration and
@@ -446,7 +395,6 @@ static struct TMH_Exchange *
 lookup_exchange (const char *exchange_url)
 {
   struct TMH_Exchange *exchange;
-  enum GNUNET_DB_QueryStatus qs;
 
   for (exchange = exchange_head;
        NULL != exchange;
@@ -459,16 +407,6 @@ lookup_exchange (const char *exchange_url)
   GNUNET_CONTAINER_DLL_insert (exchange_head,
                                exchange_tail,
                                exchange);
-  qs = TMH_db->select_exchange_keys (TMH_db->cls,
-                                     exchange->url,
-                                     &exchange->keys);
-  GNUNET_break (qs >= 0);
-  if (qs > 0)
-    exchange->state = ESTATE_DOWNLOADED;
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "The exchange `%s' is new (%d)\n",
-              exchange_url,
-              exchange->state);
   return exchange;
 }
 
@@ -539,21 +477,6 @@ set_exchange_accounts (
 
 
 /**
- * Function called with information about who is auditing
- * a particular exchange and what key the exchange is using.
- *
- * @param cls closure, will be `struct TMH_Exchange`
- * @param kr response details
- * @param[in] keys keys object returned
- */
-static void
-keys_mgmt_cb (
-  void *cls,
-  const struct TALER_EXCHANGE_KeysResponse *kr,
-  struct TALER_EXCHANGE_Keys *keys);
-
-
-/**
  * Check if we have any remaining pending requests for the
  * given @a exchange, and if we have the required data, call
  * the callback.
@@ -606,9 +529,8 @@ process_find_operations (struct TMH_Exchange *exchange)
 
     kon = NULL;
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                "Processing find operations for `%s' (%d)\n",
-                exchange->url,
-                exchange->state);
+                "Processing find operations for `%s'\n",
+                exchange->url);
     for (struct TMH_EXCHANGES_KeysOperation *ko = exchange->keys_head;
          NULL != ko;
          ko = kon)
@@ -699,61 +621,6 @@ process_wire_fees (
 
 
 /**
- * Add account restriction @a a to array of @a restrictions.
- *
- * @param[in,out] restrictions JSON array to build
- * @param r restriction to add to @a restrictions
- * @return #GNUNET_SYSERR if @a r is malformed
- */
-static enum GNUNET_GenericReturnValue
-add_restriction (json_t *restrictions,
-                 const struct TALER_EXCHANGE_AccountRestriction *r)
-{
-  json_t *jr;
-
-  jr = NULL;
-  switch (r->type)
-  {
-  case TALER_EXCHANGE_AR_INVALID:
-    GNUNET_break_op (0);
-    return GNUNET_SYSERR;
-  case TALER_EXCHANGE_AR_DENY:
-    jr = GNUNET_JSON_PACK (
-      GNUNET_JSON_pack_string ("type",
-                               "deny")
-      );
-    break;
-  case TALER_EXCHANGE_AR_REGEX:
-    jr = GNUNET_JSON_PACK (
-      GNUNET_JSON_pack_string (
-        "type",
-        "regex"),
-      GNUNET_JSON_pack_string (
-        "regex",
-        r->details.regex.posix_egrep),
-      GNUNET_JSON_pack_string (
-        "human_hint",
-        r->details.regex.human_hint),
-      GNUNET_JSON_pack_object_incref (
-        "human_hint_i18n",
-        (json_t *) r->details.regex.human_hint_i18n)
-      );
-    break;
-  }
-  if (NULL == jr)
-  {
-    GNUNET_break_op (0);
-    return GNUNET_SYSERR;
-  }
-  GNUNET_assert (0 ==
-                 json_array_append_new (restrictions,
-                                        jr));
-  return GNUNET_OK;
-
-}
-
-
-/**
  * Retry getting keys from the given exchange in the closure.
  *
  * @param cls the `struct TMH_Exchange *`
@@ -762,49 +629,23 @@ static void
 retry_exchange (void *cls)
 {
   struct TMH_Exchange *exchange = cls;
+  struct GNUNET_DB_EventHeaderP es = {
+    .size = ntohs (sizeof (es)),
+    .type = ntohs (TALER_DBEVENT_MERCHANT_EXCHANGE_FORCE_KEYS)
+  };
 
   exchange->retry_task = NULL;
-  GNUNET_assert (NULL == exchange->conn);
   exchange->retry_delay
     = GNUNET_TIME_randomized_backoff (exchange->retry_delay,
                                       RETRY_BACKOFF_THRESHOLD);
-  /* Block for the duration of the long-poller */
   exchange->first_retry
-    = GNUNET_TIME_relative_to_absolute (LONG_POLL_THRESHOLD);
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Fetching /keys from exchange %s in retry_exchange()\n",
-              exchange->url);
-  switch (exchange->state)
-  {
-  case ESTATE_FAILED:
-    exchange->state = ESTATE_REDOWNLOADING_FAILURE;
-    break;
-  case ESTATE_INIT:
-    exchange->state = ESTATE_DOWNLOADING_FIRST;
-    break;
-  case ESTATE_DOWNLOADING_FIRST:
-    GNUNET_break (0);
-    return;
-  case ESTATE_DOWNLOADED:
-    exchange->state = ESTATE_REDOWNLOADING_SUCCESS;
-    break;
-  case ESTATE_REDOWNLOADING_SUCCESS:
-    GNUNET_break (0);
-    return;
-  case ESTATE_REDOWNLOADING_FAILURE:
-    GNUNET_break (0);
-    return;
-  }
-  exchange->conn
-    = TALER_EXCHANGE_get_keys (
-        TMH_curl_ctx,
-        exchange->url,
-        exchange->keys,
-        &keys_mgmt_cb,
-        exchange);
-  /* Note: while the API spec says 'returns NULL on error', the implementation
-     actually never returns NULL. */
-  GNUNET_break (NULL != exchange->conn);
+    = GNUNET_TIME_relative_to_absolute (
+        exchange->retry_delay);
+
+  TMH_db->event_notify (TMH_db->cls,
+                        &es,
+                        exchange->url,
+                        strlen (exchange->url) + 1);
 }
 
 
@@ -853,26 +694,25 @@ TMH_EXCHANGES_keys4exchange (
   GNUNET_CONTAINER_DLL_insert (exchange->keys_head,
                                exchange->keys_tail,
                                fo);
-  if ( (NULL != exchange->keys) &&
-       (! force_download) &&
-       (GNUNET_TIME_absolute_is_future (
-          exchange->keys->key_data_expiration.abs_time)) )
+  if ( (NULL == exchange->keys) &&
+       (! force_download) )
   {
-    /* We have a valid reply, immediately return result */
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                "The exchange `%s' is ready\n",
+                "Waiting for `%skeys' already, failing query instantly\n",
                 exchange->url);
     GNUNET_assert (NULL == fo->at);
     fo->at = GNUNET_SCHEDULER_add_now (&return_keys,
                                        fo);
     return fo;
   }
-  if ( (NULL == exchange->conn) &&
-       ( (ESTATE_FAILED == exchange->state) ||
-         (ESTATE_REDOWNLOADING_FAILURE == exchange->state) ) )
+  if ( (NULL != exchange->keys) &&
+       (! force_download) &&
+       (GNUNET_TIME_absolute_is_future (
+          exchange->keys->key_data_expiration.abs_time)) )
   {
+    /* We have a valid reply, immediately return result */
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                "Already waiting for `%skeys' for a while, failing query instantly\n",
+                "The exchange `%s' is ready\n",
                 exchange->url);
     GNUNET_assert (NULL == fo->at);
     fo->at = GNUNET_SCHEDULER_add_now (&return_keys,
@@ -881,7 +721,7 @@ TMH_EXCHANGES_keys4exchange (
   }
   if ( (force_download) &&
        (GNUNET_TIME_absolute_is_future (exchange->first_retry)) &&
-       (ESTATE_DOWNLOADED == exchange->state) )
+       (NULL != exchange->keys) )
   {
     /* Return results immediately. */
     fo->at = GNUNET_SCHEDULER_add_now (&return_keys,
@@ -889,16 +729,14 @@ TMH_EXCHANGES_keys4exchange (
     /* *no* return here, we MAY schedule a 'retry_task' in the
        next block if there isn't one yet */
   }
-  if ( (NULL == exchange->retry_task) &&
-       (NULL == exchange->conn) )
+  if (NULL == exchange->retry_task)
     exchange->retry_task
       = GNUNET_SCHEDULER_add_at (exchange->first_retry,
                                  &retry_exchange,
                                  exchange);
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Next %skeys (%d) request scheduled for %s\n",
+              "Next %skeys request scheduled for %s\n",
               exchange->url,
-              exchange->state,
               GNUNET_TIME_absolute2s (
                 exchange->first_retry));
   /* No activity to launch, we are already doing so. */
@@ -976,10 +814,9 @@ free_exchange_entry (struct TMH_Exchange *exchange)
   struct FeesByWireMethod *f;
 
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Releasing %s exchange %s (%d)\n",
+              "Releasing %s exchange %s\n",
               exchange->trusted ? "trusted" : "untrusted",
-              exchange->url,
-              exchange->state);
+              exchange->url);
   GNUNET_CONTAINER_DLL_remove (exchange_head,
                                exchange_tail,
                                exchange);
@@ -999,11 +836,6 @@ free_exchange_entry (struct TMH_Exchange *exchange)
     GNUNET_free (f->wire_method);
     GNUNET_free (f);
   }
-  if (NULL != exchange->conn)
-  {
-    TALER_EXCHANGE_get_keys_cancel (exchange->conn);
-    exchange->conn = NULL;
-  }
   TALER_EXCHANGE_keys_decref (exchange->keys);
   exchange->keys = NULL;
   if (NULL != exchange->retry_task)
@@ -1019,281 +851,6 @@ free_exchange_entry (struct TMH_Exchange *exchange)
 }
 
 
-/**
- * We failed downloading /keys from @a exchange. Tell clients
- * about our failure, abort pending operations and retry later.
- *
- * @param exchange exchange that failed
- */
-static void
-fail_and_retry (struct TMH_Exchange *exchange)
-{
-  struct TMH_EXCHANGES_KeysOperation *keys;
-
-  exchange->state = ESTATE_FAILED;
-  while (NULL != (keys = exchange->keys_head))
-  {
-    keys->fc (keys->fc_cls,
-              NULL,
-              exchange);
-    TMH_EXCHANGES_keys4exchange_cancel (keys);
-  }
-  exchange->retry_delay
-    = GNUNET_TIME_randomized_backoff (exchange->retry_delay,
-                                      RETRY_BACKOFF_THRESHOLD);
-  GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-              "Failed to fetch /keys from `%s'; retrying in %s\n",
-              exchange->url,
-              GNUNET_STRINGS_relative_time_to_string (exchange->retry_delay,
-                                                      true));
-  if (NULL != exchange->retry_task)
-    GNUNET_SCHEDULER_cancel (exchange->retry_task);
-  exchange->first_retry
-    = GNUNET_TIME_relative_to_absolute (
-        exchange->retry_delay);
-  exchange->retry_task
-    = GNUNET_SCHEDULER_add_delayed (exchange->retry_delay,
-                                    &retry_exchange,
-                                    exchange);
-}
-
-
-/**
- * Update our information in the database about the
- * /keys of an exchange. Run inside of a database
- * transaction scope that will re-try and/or commit
- * depending on the return value.
- *
- * @param keys information to persist
- * @return transaction status
- */
-static enum GNUNET_DB_QueryStatus
-insert_keys_data (const struct TALER_EXCHANGE_Keys *keys)
-{
-  enum GNUNET_DB_QueryStatus qs;
-
-  /* store exchange online signing keys in our DB */
-  for (unsigned int i = 0; i<keys->num_sign_keys; i++)
-  {
-    struct TALER_EXCHANGE_SigningPublicKey *sign_key = &keys->sign_keys[i];
-
-    qs = TMH_db->insert_exchange_signkey (
-      TMH_db->cls,
-      &keys->master_pub,
-      &sign_key->key,
-      sign_key->valid_from,
-      sign_key->valid_until,
-      sign_key->valid_legal,
-      &sign_key->master_sig);
-    /* 0 is OK, we may already have the key in the DB! */
-    if (0 > qs)
-    {
-      GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-      return qs;
-    }
-  }
-
-  qs = TMH_db->insert_exchange_keys (TMH_db->cls,
-                                     keys);
-  if (0 > qs)
-  {
-    GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-    return qs;
-  }
-
-  qs = TMH_db->delete_exchange_accounts (TMH_db->cls,
-                                         &keys->master_pub);
-  if (0 > qs)
-  {
-    GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-    return qs;
-  }
-
-  for (unsigned int i = 0; i<keys->accounts_len; i++)
-  {
-    const struct TALER_EXCHANGE_WireAccount *account = &keys->accounts[i];
-    json_t *debit_restrictions;
-    json_t *credit_restrictions;
-
-    debit_restrictions = json_array ();
-    GNUNET_assert (NULL != debit_restrictions);
-    credit_restrictions = json_array ();
-    GNUNET_assert (NULL != credit_restrictions);
-    for (unsigned int j = 0; j<account->debit_restrictions_length; j++)
-    {
-      if (GNUNET_OK !=
-          add_restriction (debit_restrictions,
-                           &account->debit_restrictions[j]))
-      {
-        TMH_db->rollback (TMH_db->cls);
-        GNUNET_break (0);
-        json_decref (debit_restrictions);
-        json_decref (credit_restrictions);
-        return GNUNET_DB_STATUS_HARD_ERROR;
-      }
-    }
-    for (unsigned int j = 0; j<account->credit_restrictions_length; j++)
-    {
-      if (GNUNET_OK !=
-          add_restriction (credit_restrictions,
-                           &account->credit_restrictions[j]))
-      {
-        TMH_db->rollback (TMH_db->cls);
-        GNUNET_break (0);
-        json_decref (debit_restrictions);
-        json_decref (credit_restrictions);
-        return GNUNET_DB_STATUS_HARD_ERROR;
-      }
-    }
-    qs = TMH_db->insert_exchange_account (
-      TMH_db->cls,
-      &keys->master_pub,
-      account->payto_uri,
-      account->conversion_url,
-      debit_restrictions,
-      credit_restrictions,
-      &account->master_sig);
-    json_decref (debit_restrictions);
-    json_decref (credit_restrictions);
-    if (qs < 0)
-    {
-      GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-      return qs;
-    }
-  } /* end 'for all accounts' */
-
-  for (unsigned int i = 0; i<keys->fees_len; i++)
-  {
-    const struct TALER_EXCHANGE_WireFeesByMethod *fbm = &keys->fees[i];
-    const char *wire_method = fbm->method;
-    const struct TALER_EXCHANGE_WireAggregateFees *fees = fbm->fees_head;
-
-    while (NULL != fees)
-    {
-      struct GNUNET_HashCode h_wire_method;
-
-      GNUNET_CRYPTO_hash (wire_method,
-                          strlen (wire_method) + 1,
-                          &h_wire_method);
-      qs = TMH_db->store_wire_fee_by_exchange (TMH_db->cls,
-                                               &keys->master_pub,
-                                               &h_wire_method,
-                                               &fees->fees,
-                                               fees->start_date,
-                                               fees->end_date,
-                                               &fees->master_sig);
-      if (0 > qs)
-      {
-        GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-        return qs;
-      }
-      fees = fees->next;
-    } /* all fees for this method */
-  } /* for all methods (i) */
-
-  {
-    struct GNUNET_DB_EventHeaderP es = {
-      .size = ntohs (sizeof (es)),
-      .type = ntohs (TALER_DBEVENT_MERCHANT_EXCHANGE_KEYS)
-    };
-
-    TMH_db->event_notify (TMH_db->cls,
-                          &es,
-                          keys->exchange_url,
-                          strlen (keys->exchange_url) + 1);
-  }
-  return qs;
-}
-
-
-static void
-keys_mgmt_cb (void *cls,
-              const struct TALER_EXCHANGE_KeysResponse *kr,
-              struct TALER_EXCHANGE_Keys *keys)
-{
-  struct TMH_Exchange *exchange = cls;
-  enum GNUNET_DB_QueryStatus qs;
-
-  exchange->conn = NULL;
-  if (MHD_HTTP_OK != kr->hr.http_status)
-  {
-    if (GNUNET_TIME_absolute_is_future (exchange->first_retry))
-    {
-      /* /keys failed *before* the long polling threshold.
-         We apply the exponential back-off from now. */
-      exchange->first_retry
-        = GNUNET_TIME_relative_to_absolute (
-            exchange->retry_delay);
-    }
-    fail_and_retry (exchange);
-    TALER_EXCHANGE_keys_decref (keys);
-    return;
-  }
-  if (NULL == exchange->currency)
-    exchange->currency = GNUNET_strdup (keys->currency);
-  if (0 != strcmp (exchange->currency,
-                   keys->currency))
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                "/keys response from `%s' is for currency `%s', but we expected `%s'\n",
-                exchange->url,
-                keys->currency,
-                exchange->currency);
-    fail_and_retry (exchange);
-    TALER_EXCHANGE_keys_decref (keys);
-    return;
-  }
-  exchange->state = ESTATE_DOWNLOADED;
-  TMH_db->preflight (TMH_db->cls);
-  for (unsigned int r = 0; r<MAX_RETRIES; r++)
-  {
-    if (GNUNET_OK !=
-        TMH_db->start (TMH_db->cls,
-                       "update exchange key data"))
-    {
-      TMH_db->rollback (TMH_db->cls);
-      GNUNET_break (0);
-      fail_and_retry (exchange);
-      TALER_EXCHANGE_keys_decref (keys);
-      return;
-    }
-
-    qs = insert_keys_data (keys);
-    if (qs < 0)
-    {
-      TMH_db->rollback (TMH_db->cls);
-      if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
-        continue;
-      GNUNET_break (0);
-      fail_and_retry (exchange);
-      TALER_EXCHANGE_keys_decref (keys);
-      return;
-    }
-
-    qs = TMH_db->commit (TMH_db->cls);
-    if (qs < 0)
-    {
-      TMH_db->rollback (TMH_db->cls);
-      if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
-        continue;
-      GNUNET_break (0);
-      fail_and_retry (exchange);
-      TALER_EXCHANGE_keys_decref (keys);
-      return;
-    }
-  } /* end of retry loop */
-  if (qs < 0)
-  {
-    GNUNET_break (0);
-    fail_and_retry (exchange);
-    TALER_EXCHANGE_keys_decref (keys);
-    return;
-  }
-  TALER_EXCHANGE_keys_decref (keys);
-  exchange->retry_delay = GNUNET_TIME_UNIT_ZERO;
-}
-
-
 enum GNUNET_GenericReturnValue
 TMH_EXCHANGES_lookup_wire_fee (
   const struct TMH_Exchange *exchange,
@@ -1326,6 +883,7 @@ TMH_exchange_check_debit (
                 exchange->url);
     return GNUNET_SYSERR;
   }
+  /* FIXME: move into convenience function in libtalerexchange? See also taler-merchant-httpd_private-get-instances-ID-kyc.c, taler-merchant-kyccheck (!) */
   for (struct ExchangeAccount *acc = exchange->acc_head;
        NULL != acc;
        acc = acc->next)
@@ -1432,6 +990,107 @@ TMH_test_exchange_configured_for_currency (
 
 
 /**
+ * (Re)load of keys from DB.
+ *
+ * @param exchange exchange to reload keys of
+ */
+static void
+reload_exchange_keys (struct TMH_Exchange *exchange)
+{
+  enum GNUNET_DB_QueryStatus qs;
+  struct TALER_EXCHANGE_Keys *keys;
+
+  qs = TMH_db->select_exchange_keys (TMH_db->cls,
+                                     exchange->url,
+                                     &keys);
+  if (qs < 0)
+  {
+    GNUNET_break (0);
+    return;
+  }
+  if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "No keys yet for `%s'\n",
+                exchange->url);
+    return;
+  }
+  exchange->retry_delay = GNUNET_TIME_UNIT_ZERO;
+  if (NULL == exchange->currency)
+    exchange->currency = GNUNET_strdup (keys->currency);
+  if (0 != strcmp (keys->currency,
+                   exchange->currency))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "/keys cached in our database are for currency `%s', but we expected `%s'\n",
+                keys->currency,
+                exchange->currency);
+    return;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Loaded /keys from database with %u accounts\n",
+              keys->accounts_len);
+  if (GNUNET_OK !=
+      set_exchange_accounts (exchange,
+                             keys->accounts_len,
+                             keys->accounts))
+  {
+    /* invalid account specification given */
+    GNUNET_break_op (0);
+    /* but: we can continue anyway, things may just not
+       work, but probably better than to not keep going. */
+  }
+  if (GNUNET_OK !=
+      process_wire_fees (exchange,
+                         &keys->master_pub,
+                         keys->fees_len,
+                         keys->fees))
+  {
+    /* invalid wire fee specification given */
+    GNUNET_break_op (0);
+    /* but: we can continue anyway, things may just not
+       work, but probably better than to not keep going. */
+    return;
+  }
+
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Reloaded /keys of %s from database\n",
+              exchange->url);
+  TALER_EXCHANGE_keys_decref (exchange->keys);
+  exchange->keys = keys;
+  if ( (exchange->trusted) &&
+       (0 != GNUNET_memcmp (&exchange->master_pub,
+                            &keys->master_pub)) )
+  {
+    /* master pub differs => do not trust the exchange (without auditor) */
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "Master public key of exchange `%s' differs from our configuration. Not trusting exchange.\n",
+                exchange->url);
+    exchange->trusted = false;
+  }
+  if (! exchange->trusted)
+  {
+    exchange->master_pub = keys->master_pub;
+    for (struct TMH_Exchange *e = exchange_head;
+         NULL != e;
+         e = e->next)
+    {
+      if (e == exchange)
+        continue;
+      if (! e->trusted)
+        continue;
+      if (0 ==
+          GNUNET_memcmp (&e->master_pub,
+                         &exchange->master_pub))
+        exchange->trusted = true; /* same exchange, different URL => trust applies */
+    }
+  }
+
+  process_find_operations (exchange);
+}
+
+
+/**
  * Function called on each configuration section. Finds sections
  * about exchanges, parses the entries.
  *
@@ -1484,10 +1143,7 @@ accept_exchanges (void *cls,
   }
   exchange = lookup_exchange (url);
   GNUNET_free (url);
-  if (NULL == exchange->currency)
-    exchange->currency = currency;
-  else
-    GNUNET_free (currency);
+  exchange->currency = currency;
   if (GNUNET_OK ==
       GNUNET_CONFIGURATION_get_value_string (cfg,
                                              section,
@@ -1522,6 +1178,7 @@ accept_exchanges (void *cls,
               "Setup exchange %s as %s\n",
               exchange->url,
               exchange->trusted ? "trusted" : "untrusted");
+  reload_exchange_keys (exchange);
   if (NULL != exchange->retry_task)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
@@ -1549,10 +1206,8 @@ update_exchange_keys (void *cls,
                       const void *extra,
                       size_t extra_len)
 {
-  enum GNUNET_DB_QueryStatus qs;
   const char *url = extra;
   struct TMH_Exchange *exchange;
-  struct TALER_EXCHANGE_Keys *keys;
 
   if ( (NULL == extra) ||
        (0 == extra_len) )
@@ -1569,85 +1224,7 @@ update_exchange_keys (void *cls,
               "Received keys change notification: reload `%s'\n",
               url);
   exchange = lookup_exchange (url);
-  qs = TMH_db->select_exchange_keys (TMH_db->cls,
-                                     url,
-                                     &keys);
-  if (qs <= 0)
-  {
-    GNUNET_break (0);
-    return;
-  }
-  if (NULL == exchange->currency)
-    exchange->currency = GNUNET_strdup (keys->currency);
-  if (0 != strcmp (keys->currency,
-                   exchange->currency))
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                "/keys cached in our database are for currency `%s', but we expected `%s'\n",
-                keys->currency,
-                exchange->currency);
-    return;
-  }
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Loaded /keys from database with %u accounts\n",
-              keys->accounts_len);
-  if (GNUNET_OK !=
-      set_exchange_accounts (exchange,
-                             keys->accounts_len,
-                             keys->accounts))
-  {
-    /* invalid account specification given */
-    GNUNET_break_op (0);
-    /* but: we can continue anyway, things may just not
-       work, but probably better than to not keep going. */
-  }
-  if (GNUNET_OK !=
-      process_wire_fees (exchange,
-                         &keys->master_pub,
-                         keys->fees_len,
-                         keys->fees))
-  {
-    /* invalid wire fee specification given */
-    GNUNET_break_op (0);
-    /* but: we can continue anyway, things may just not
-       work, but probably better than to not keep going. */
-    return;
-  }
-
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Reloaded /keys of %s from database\n",
-              url);
-  TALER_EXCHANGE_keys_decref (exchange->keys);
-  exchange->keys = keys;
-  if ( (exchange->trusted) &&
-       (0 != GNUNET_memcmp (&exchange->master_pub,
-                            &keys->master_pub)) )
-  {
-    /* master pub differs => do not trust the exchange (without auditor) */
-    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                "Master public key of exchange `%s' differs from our configuration. Not trusting exchange.\n",
-                exchange->url);
-    exchange->trusted = false;
-  }
-  if (! exchange->trusted)
-  {
-    exchange->master_pub = keys->master_pub;
-    for (struct TMH_Exchange *e = exchange_head;
-         NULL != e;
-         e = e->next)
-    {
-      if (e == exchange)
-        continue;
-      if (! e->trusted)
-        continue;
-      if (0 ==
-          GNUNET_memcmp (&e->master_pub,
-                         &exchange->master_pub))
-        exchange->trusted = true; /* same exchange, different URL => trust applies */
-    }
-  }
-
-  process_find_operations (exchange);
+  reload_exchange_keys (exchange);
 }
 
 
diff --git a/src/backend/taler-merchant-kyccheck.c b/src/backend/taler-merchant-kyccheck.c
index c55b12c4..933d0984 100644
--- a/src/backend/taler-merchant-kyccheck.c
+++ b/src/backend/taler-merchant-kyccheck.c
@@ -645,7 +645,7 @@ is_eligible (struct TALER_EXCHANGE_Keys *keys,
   /* For all accounts of the exchange */
   for (unsigned int i = 0; i<keys->accounts_len; i++)
   {
-    /* FIXME: move into convenience function in libtalerexchange? See also taler-merchant-httpd_private-get-instances-ID-kyc.c*/
+    /* FIXME: move into convenience function in libtalerexchange? See also taler-merchant-httpd_private-get-instances-ID-kyc.c, taler-merchant-httpd_exchanges (!)*/
     struct TALER_EXCHANGE_WireAccount *account
       = &keys->accounts[i];
     bool account_restricted = false;
diff --git a/src/testing/test_merchant_instance_auth.sh b/src/testing/test_merchant_instance_auth.sh
index 85857b4f..1959628b 100755
--- a/src/testing/test_merchant_instance_auth.sh
+++ b/src/testing/test_merchant_instance_auth.sh
@@ -72,6 +72,7 @@ setup -c test_template.conf -ef -u "exchange-account-2"
 
 NEW_SECRET=secret-token:different_value
 
+taler-merchant-exchangekeyupdate -c "${CONF}" -L DEBUG 2> taler-merchant-exchangekeyupdate.log &
 taler-merchant-httpd -a "${NEW_SECRET}" -c "${CONF}" -L DEBUG 2> taler-merchant-httpd.log &
 # Install cleanup handler (except for kill -9)
 trap my_cleanup EXIT