merging

49 files changed, 1164 insertions, 401 deletions

diff --git a/src/auditor/taler-auditor-httpd.c b/src/auditor/taler-auditor-httpd.c
index 4d5537e51..043d5b148 100644
--- a/src/auditor/taler-auditor-httpd.c
+++ b/src/auditor/taler-auditor-httpd.c
@@ -594,7 +594,7 @@ main (int argc,
   if (GNUNET_OK !=
       auditor_serve_process_config ())
     return 1;
-
+  TEAH_DEPOSIT_CONFIRMATION_init ();
   /* check for systemd-style FD passing */
   listen_pid = getenv ("LISTEN_PID");
   listen_fds = getenv ("LISTEN_FDS");
@@ -635,7 +635,10 @@ main (int argc,
     fh = TALER_MHD_open_unix_path (serve_unixpath,
                                    unixpath_mode);
     if (-1 == fh)
+    {
+      TEAH_DEPOSIT_CONFIRMATION_done ();
       return 1;
+    }
   }
 
   mhd
@@ -659,6 +662,7 @@ main (int argc,
   {
     fprintf (stderr,
              "Failed to start HTTP server.\n");
+    TEAH_DEPOSIT_CONFIRMATION_done ();
     return 1;
   }
 
@@ -732,6 +736,7 @@ main (int argc,
     break;
   }
   TALER_AUDITORDB_plugin_unload (TAH_plugin);
+  TEAH_DEPOSIT_CONFIRMATION_done ();
   return (GNUNET_SYSERR == ret) ? 1 : 0;
 }
 
diff --git a/src/auditor/taler-auditor-httpd_deposit-confirmation.c b/src/auditor/taler-auditor-httpd_deposit-confirmation.c
index 7759b5538..ab233ebc3 100644
--- a/src/auditor/taler-auditor-httpd_deposit-confirmation.c
+++ b/src/auditor/taler-auditor-httpd_deposit-confirmation.c
@@ -33,6 +33,19 @@
 
 
 /**
+ * Cache of already verified exchange signing keys.  Maps the hash of the
+ * `struct TALER_ExchangeSigningKeyValidityPS` to the (static) string
+ * "verified".  Access to this map is guarded by the #lock.
+ */
+static struct GNUNET_CONTAINER_MultiHashMap *cache;
+
+/**
+ * Lock for operations on #cache.
+ */
+static pthread_mutex_t lock;
+
+
+/**
  * We have parsed the JSON information about the deposit, do some
  * basic sanity checks (especially that the signature on the coin is
  * valid, and that this type of coin exists) and then execute the
@@ -55,6 +68,8 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
   struct TALER_AUDITORDB_Session *session;
   enum GNUNET_DB_QueryStatus qs;
   struct GNUNET_TIME_Absolute now;
+  struct GNUNET_HashCode h;
+  int cached;
 
   now = GNUNET_TIME_absolute_get ();
   if ( (es->ep_start.abs_value_us > now.abs_value_us) ||
@@ -68,10 +83,6 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
                                        "master_sig (expired)");
   }
 
-  /* TODO (#6052): consider having an in-memory cache of already
-     verified exchange signing keys, this could save us
-     a signature check AND a database transaction per
-     operation. */
   /* check exchange signing key signature */
   skv.purpose.purpose = htonl (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY);
   skv.purpose.size = htonl (sizeof (struct TALER_ExchangeSigningKeyValidityPS));
@@ -80,18 +91,15 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
   skv.expire = GNUNET_TIME_absolute_hton (es->ep_expire);
   skv.end = GNUNET_TIME_absolute_hton (es->ep_end);
   skv.signkey_pub = es->exchange_pub;
-  if (GNUNET_OK !=
-      GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY,
-                                  &skv.purpose,
-                                  &es->master_sig.eddsa_signature,
-                                  &es->master_public_key.eddsa_pub))
-  {
-    TALER_LOG_WARNING ("Invalid signature on exchange signing key\n");
-    return TALER_MHD_reply_with_error (connection,
-                                       MHD_HTTP_FORBIDDEN,
-                                       TALER_EC_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
-                                       "master_sig");
-  }
+
+  /* check our cache */
+  GNUNET_CRYPTO_hash (&skv,
+                      sizeof (skv),
+                      &h);
+  GNUNET_assert (0 == pthread_mutex_lock (&lock));
+  cached = GNUNET_CONTAINER_multihashmap_contains (cache,
+                                                   &h);
+  GNUNET_assert (0 == pthread_mutex_unlock (&lock));
 
   session = TAH_plugin->get_session (TAH_plugin->cls);
   if (NULL == session)
@@ -102,18 +110,45 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
                                        TALER_EC_DB_SETUP_FAILED,
                                        "failed to establish session with database");
   }
-  /* execute transaction */
-  qs = TAH_plugin->insert_exchange_signkey (TAH_plugin->cls,
-                                            session,
-                                            es);
-  if (0 > qs)
+  if (! cached)
   {
-    GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
-    TALER_LOG_WARNING ("Failed to store exchange signing key in database\n");
-    return TALER_MHD_reply_with_error (connection,
-                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                       TALER_EC_AUDITOR_EXCHANGE_STORE_DB_ERROR,
-                                       "failed to persist exchange signing key");
+    /* Not in cache, need to verify the signature, persist it, and possibly cache it */
+    if (GNUNET_OK !=
+        GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY,
+                                    &skv.purpose,
+                                    &es->master_sig.eddsa_signature,
+                                    &es->master_public_key.eddsa_pub))
+    {
+      TALER_LOG_WARNING ("Invalid signature on exchange signing key\n");
+      return TALER_MHD_reply_with_error (connection,
+                                         MHD_HTTP_FORBIDDEN,
+                                         TALER_EC_DEPOSIT_CONFIRMATION_SIGNATURE_INVALID,
+                                         "master_sig");
+    }
+
+    /* execute transaction */
+    qs = TAH_plugin->insert_exchange_signkey (TAH_plugin->cls,
+                                              session,
+                                              es);
+    if (0 > qs)
+    {
+      GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
+      TALER_LOG_WARNING ("Failed to store exchange signing key in database\n");
+      return TALER_MHD_reply_with_error (connection,
+                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                         TALER_EC_AUDITOR_EXCHANGE_STORE_DB_ERROR,
+                                         "failed to persist exchange signing key");
+    }
+
+    /* Cache it, due to concurreny it might already be in the cache,
+       so we do not cache it twice but also don't insist on the 'put' to
+       succeed. */
+    GNUNET_assert (0 == pthread_mutex_lock (&lock));
+    (void) GNUNET_CONTAINER_multihashmap_put (cache,
+                                              &h,
+                                              "verified",
+                                              GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
+    GNUNET_assert (0 == pthread_mutex_unlock (&lock));
   }
 
   /* check deposit confirmation signature */
@@ -237,4 +272,28 @@ TAH_DEPOSIT_CONFIRMATION_handler (struct TAH_RequestHandler *rh,
 }
 
 
+/**
+ * Initialize subsystem.
+ */
+void
+TEAH_DEPOSIT_CONFIRMATION_init (void)
+{
+  cache = GNUNET_CONTAINER_multihashmap_create (32,
+                                                GNUNET_NO);
+  GNUNET_assert (0 == pthread_mutex_init (&lock, NULL));
+}
+
+
+/**
+ * Shut down subsystem.
+ */
+void
+TEAH_DEPOSIT_CONFIRMATION_done (void)
+{
+  GNUNET_CONTAINER_multihashmap_destroy (cache);
+  cache = NULL;
+  GNUNET_assert (0 == pthread_mutex_destroy (&lock));
+}
+
+
 /* end of taler-auditor-httpd_deposit-confirmation.c */
diff --git a/src/auditor/taler-auditor-httpd_deposit-confirmation.h b/src/auditor/taler-auditor-httpd_deposit-confirmation.h
index 842eb3562..531f3c93c 100644
--- a/src/auditor/taler-auditor-httpd_deposit-confirmation.h
+++ b/src/auditor/taler-auditor-httpd_deposit-confirmation.h
@@ -25,6 +25,18 @@
 #include <microhttpd.h>
 #include "taler-auditor-httpd.h"
 
+/**
+ * Initialize subsystem.
+ */
+void
+TEAH_DEPOSIT_CONFIRMATION_init (void);
+
+/**
+ * Shut down subsystem.
+ */
+void
+TEAH_DEPOSIT_CONFIRMATION_done (void);
+
 
 /**
  * Handle a "/deposit-confirmation" request.  Parses the JSON, and, if
diff --git a/src/auditor/taler-auditor.c b/src/auditor/taler-auditor.c
index 4e32d2a4e..0ec5e2d75 100644
--- a/src/auditor/taler-auditor.c
+++ b/src/auditor/taler-auditor.c
@@ -5709,6 +5709,8 @@ main (int argc,
                                "restart",
                                "restart audit from the beginning (required on first run)",
                                &restart),
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
     GNUNET_GETOPT_OPTION_END
   };
 
diff --git a/src/auditor/taler-wire-auditor.c b/src/auditor/taler-wire-auditor.c
index 94fd773c9..92664fb8f 100644
--- a/src/auditor/taler-wire-auditor.c
+++ b/src/auditor/taler-wire-auditor.c
@@ -704,13 +704,15 @@ check_pending_rc (void *cls,
                 TALER_amount_add (&total_closure_amount_lag,
                                   &total_closure_amount_lag,
                                   &rc->amount));
-  report (report_closure_lags,
-          json_pack ("{s:I, s:o, s:o, s:o, s:s}",
-                     "row", (json_int_t) rc->rowid,
-                     "amount", TALER_JSON_from_amount (&rc->amount),
-                     "deadline", json_from_time_abs (rc->execution_date),
-                     "wtid", GNUNET_JSON_from_data_auto (&rc->wtid),
-                     "account", rc->receiver_account));
+  if ( (0 != rc->amount.value) ||
+       (0 != rc->amount.fraction) )
+    report (report_closure_lags,
+            json_pack ("{s:I, s:o, s:o, s:o, s:s}",
+                       "row", (json_int_t) rc->rowid,
+                       "amount", TALER_JSON_from_amount (&rc->amount),
+                       "deadline", json_from_time_abs (rc->execution_date),
+                       "wtid", GNUNET_JSON_from_data_auto (&rc->wtid),
+                       "account", rc->receiver_account));
   pp.last_reserve_close_uuid
     = GNUNET_MIN (pp.last_reserve_close_uuid,
                   rc->rowid);
@@ -2312,6 +2314,8 @@ main (int argc,
                                "restart",
                                "restart audit from the beginning (required on first run)",
                                &restart),
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
     GNUNET_GETOPT_OPTION_END
   };
 
diff --git a/src/auditor/test-auditor.sh b/src/auditor/test-auditor.sh
index 00ed05230..5f7d0c8c3 100755
--- a/src/auditor/test-auditor.sh
+++ b/src/auditor/test-auditor.sh
@@ -1473,6 +1473,49 @@ echo "UPDATE deposits SET wire='$OLD_WIRE' WHERE deposit_serial_id=${SERIAL}" |
 
 }
 
+# Test for duplicate wire transfer subject
+function test_27() {
+echo "===========27: duplicate WTID detection ================="
+
+# Check wire transfer lag reported (no aggregator!)
+# NOTE: This test is EXPECTED to fail for ~1h after
+# re-generating the test database as we do not
+# report lag of less than 1h (see GRACE_PERIOD in
+# taler-wire-auditor.c)
+if [ $DATABASE_AGE -gt 3600 ]
+then
+
+    pre_audit aggregator
+
+    # Obtain data to duplicate.
+    ID=`echo "SELECT id FROM app_banktransaction WHERE debit_account_id=2 LIMIT 1" | psql $DB -Aqt`
+    WTID=`echo "SELECT subject FROM app_banktransaction WHERE debit_account_id=2 LIMIT 1" | psql $DB -Aqt`
+    echo "INSERT INTO app_banktransaction (amount,subject,date,credit_account_id,debit_account_id,cancelled) VALUES ('TESTKUDOS:1','$WTID',NOW(),12,2,'f')" | psql -Aqt $DB
+
+    audit_only
+    post_audit
+
+    echo -n "Testing inconsistency detection... "
+
+    AMOUNT=`jq -r .wire_format_inconsistencies[0].amount < test-wire-audit.json`
+    if test "${AMOUNT}" != "TESTKUDOS:1"
+    then
+        exit_fail "Amount wrong, got ${AMOUNT}"
+    fi
+
+    AMOUNT=`jq -r .total_wire_format_amount < test-wire-audit.json`
+    if test "${AMOUNT}" != "TESTKUDOS:1"
+    then
+        exit_fail "Wrong total wire format amount, got $AMOUNT"
+    fi
+
+    # cannot easily undo aggregator, hence full reload
+    full_reload
+else
+    echo "Test skipped (database too new)"
+fi
+
+}
 
 
 # **************************************************
diff --git a/src/auditordb/Makefile.am b/src/auditordb/Makefile.am
index 1378c5496..3efdc200e 100644
--- a/src/auditordb/Makefile.am
+++ b/src/auditordb/Makefile.am
@@ -14,8 +14,8 @@ pkgcfg_DATA = \
 sqldir = $(prefix)/share/taler/sql/auditor/
 
 sql_DATA = \
-  0000.sql \
-  0001.sql \
+  auditor-0000.sql \
+  auditor-0001.sql \
   drop0000.sql \
   restart0000.sql
 
diff --git a/src/auditordb/0000.sql b/src/auditordb/auditor-0000.sql
index 1483e2015..1483e2015 100644
--- a/src/auditordb/0000.sql
+++ b/src/auditordb/auditor-0000.sql
diff --git a/src/auditordb/0001.sql b/src/auditordb/auditor-0001.sql
index 7f47f0357..3e666519c 100644
--- a/src/auditordb/0001.sql
+++ b/src/auditordb/auditor-0001.sql
@@ -115,7 +115,7 @@ CREATE TABLE IF NOT EXISTS auditor_reserves
   ,auditor_reserves_rowid BIGSERIAL UNIQUE
   ,origin_account TEXT
   );
-CREATE INDEX auditor_reserves_by_reserve_pub
+CREATE INDEX IF NOT EXISTS auditor_reserves_by_reserve_pub
   ON auditor_reserves
   (reserve_pub);
 -- Table with the sum of the balances of all customer reserves
@@ -203,7 +203,7 @@ CREATE TABLE IF NOT EXISTS auditor_historic_reserve_summary
   ,reserve_profits_val INT8 NOT NULL
   ,reserve_profits_frac INT4 NOT NULL
   );
-CREATE INDEX auditor_historic_reserve_summary_by_master_pub_start_date
+CREATE INDEX IF NOT EXISTS auditor_historic_reserve_summary_by_master_pub_start_date
   ON auditor_historic_reserve_summary
   (master_pub
   ,start_date);
diff --git a/src/auditordb/auditordb_plugin.c b/src/auditordb/auditordb_plugin.c
index 19717fe87..d04e8815a 100644
--- a/src/auditordb/auditordb_plugin.c
+++ b/src/auditordb/auditordb_plugin.c
@@ -35,7 +35,6 @@ TALER_AUDITORDB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
   char *plugin_name;
   char *lib_name;
-  struct GNUNET_CONFIGURATION_Handle *cfg_dup;
   struct TALER_AUDITORDB_Plugin *plugin;
 
   if (GNUNET_SYSERR ==
@@ -53,14 +52,12 @@ TALER_AUDITORDB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
                           "libtaler_plugin_auditordb_%s",
                           plugin_name);
   GNUNET_free (plugin_name);
-  cfg_dup = GNUNET_CONFIGURATION_dup (cfg);
   plugin = GNUNET_PLUGIN_load (lib_name,
-                               cfg_dup);
+                               (void *) cfg);
   if (NULL != plugin)
     plugin->library_name = lib_name;
   else
     GNUNET_free (lib_name);
-  GNUNET_CONFIGURATION_destroy (cfg_dup);
   return plugin;
 }
 
diff --git a/src/auditordb/plugin_auditordb_postgres.c b/src/auditordb/plugin_auditordb_postgres.c
index 30db303b0..ca07d406b 100644
--- a/src/auditordb/plugin_auditordb_postgres.c
+++ b/src/auditordb/plugin_auditordb_postgres.c
@@ -80,15 +80,9 @@ struct PostgresClosure
   pthread_key_t db_conn_threadlocal;
 
   /**
-   * Directory with SQL statements to run to create tables.
+   * Our configuration.
    */
-  char *sql_dir;
-
-  /**
-   * Database connection string, as read from
-   * the configuration.
-   */
-  char *connection_cfg_str;
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
 
   /**
    * Which currency should we assume all amounts to be in?
@@ -114,16 +108,12 @@ postgres_drop_tables (void *cls,
 {
   struct PostgresClosure *pc = cls;
   struct GNUNET_PQ_Context *conn;
-  char *exec_dir;
-
-  GNUNET_asprintf (&exec_dir,
-                   (drop_exchangelist) ? "%sdrop" : "%srestart",
-                   pc->sql_dir);
-  conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                            exec_dir,
-                            NULL,
-                            NULL);
-  GNUNET_free (exec_dir);
+
+  conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                     "auditordb-postgres",
+                                     (drop_exchangelist) ? "drop" : "restart",
+                                     NULL,
+                                     NULL);
   if (NULL == conn)
     return GNUNET_SYSERR;
   GNUNET_PQ_disconnect (conn);
@@ -143,10 +133,11 @@ postgres_create_tables (void *cls)
   struct PostgresClosure *pc = cls;
   struct GNUNET_PQ_Context *conn;
 
-  conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                            pc->sql_dir,
-                            NULL,
-                            NULL);
+  conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                     "auditordb-postgres",
+                                     "auditor-",
+                                     NULL,
+                                     NULL);
   if (NULL == conn)
     return GNUNET_SYSERR;
   GNUNET_PQ_disconnect (conn);
@@ -734,10 +725,11 @@ postgres_get_session (void *cls)
     GNUNET_PQ_reconnect_if_down (session->conn);
     return session;
   }
-  db_conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                               NULL,
-                               NULL,
-                               ps);
+  db_conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                        "auditordb-postgres",
+                                        NULL,
+                                        NULL,
+                                        ps);
   if (NULL == db_conn)
     return NULL;
   session = GNUNET_new (struct TALER_AUDITORDB_Session);
@@ -897,10 +889,11 @@ postgres_gc (void *cls)
   };
 
   now = GNUNET_TIME_absolute_get ();
-  conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                            NULL,
-                            NULL,
-                            ps);
+  conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                     "auditordb-postgres",
+                                     NULL,
+                                     NULL,
+                                     ps);
   if (NULL == conn)
     return GNUNET_SYSERR;
   GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
@@ -3244,53 +3237,19 @@ postgres_get_predicted_balance (void *cls,
 void *
 libtaler_plugin_auditordb_postgres_init (void *cls)
 {
-  struct GNUNET_CONFIGURATION_Handle *cfg = cls;
+  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
   struct PostgresClosure *pg;
   struct TALER_AUDITORDB_Plugin *plugin;
-  const char *ec;
 
   pg = GNUNET_new (struct PostgresClosure);
-  if (GNUNET_OK !=
-      GNUNET_CONFIGURATION_get_value_filename (cfg,
-                                               "auditordb-postgres",
-                                               "SQL_DIR",
-                                               &pg->sql_dir))
-  {
-    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
-                               "auditordb-postgres",
-                               "SQL_DIR");
-    GNUNET_free (pg);
-    return NULL;
-  }
+  pg->cfg = cfg;
   if (0 != pthread_key_create (&pg->db_conn_threadlocal,
                                &db_conn_destroy))
   {
     TALER_LOG_ERROR ("Cannnot create pthread key.\n");
-    GNUNET_free (pg->sql_dir);
     GNUNET_free (pg);
     return NULL;
   }
-  ec = getenv ("TALER_AUDITORDB_POSTGRES_CONFIG");
-  if (NULL != ec)
-  {
-    pg->connection_cfg_str = GNUNET_strdup (ec);
-  }
-  else
-  {
-    if (GNUNET_OK !=
-        GNUNET_CONFIGURATION_get_value_string (cfg,
-                                               "auditordb-postgres",
-                                               "CONFIG",
-                                               &pg->connection_cfg_str))
-    {
-      GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
-                                 "auditordb-postgres",
-                                 "CONFIG");
-      GNUNET_free (pg->sql_dir);
-      GNUNET_free (pg);
-      return NULL;
-    }
-  }
   if (GNUNET_OK !=
       GNUNET_CONFIGURATION_get_value_string (cfg,
                                              "taler",
@@ -3300,8 +3259,6 @@ libtaler_plugin_auditordb_postgres_init (void *cls)
     GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
                                "taler",
                                "CURRENCY");
-    GNUNET_free (pg->connection_cfg_str);
-    GNUNET_free (pg->sql_dir);
     GNUNET_free (pg);
     return NULL;
   }
@@ -3407,8 +3364,6 @@ libtaler_plugin_auditordb_postgres_done (void *cls)
   struct TALER_AUDITORDB_Plugin *plugin = cls;
   struct PostgresClosure *pg = plugin->cls;
 
-  GNUNET_free (pg->connection_cfg_str);
-  GNUNET_free (pg->sql_dir);
   GNUNET_free (pg->currency);
   GNUNET_free (pg);
   GNUNET_free (plugin);
diff --git a/src/bank-lib/Makefile.am b/src/bank-lib/Makefile.am
index 729f96e15..7227ad068 100644
--- a/src/bank-lib/Makefile.am
+++ b/src/bank-lib/Makefile.am
@@ -38,6 +38,7 @@ libtalerbank_la_LDFLAGS = \
 libtalerbank_la_SOURCES = \
   bank_api_admin.c \
   bank_api_common.c bank_api_common.h \
+  bank_api_config.c \
   bank_api_credit.c \
   bank_api_debit.c \
   bank_api_transfer.c \
diff --git a/src/bank-lib/bank_api_config.c b/src/bank-lib/bank_api_config.c
new file mode 100644
index 000000000..a84e4ff85
--- /dev/null
+++ b/src/bank-lib/bank_api_config.c
@@ -0,0 +1,255 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2017--2020 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/>
+*/
+/**
+ * @file bank-lib/bank_api_config.c
+ * @brief Implementation of the /config request
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "bank_api_common.h"
+#include <microhttpd.h> /* just for HTTP status codes */
+#include "taler_signatures.h"
+
+/**
+ * Protocol version we implement.
+ */
+#define BANK_PROTOCOL_CURRENT 0
+
+/**
+ * How many revisions back are we compatible to.
+ */
+#define BANK_PROTOCOL_AGE 0
+
+
+/**
+ * @brief A /config Handle
+ */
+struct TALER_BANK_ConfigHandle
+{
+
+  /**
+   * The url for this request.
+   */
+  char *request_url;
+
+  /**
+   * Handle for the request.
+   */
+  struct GNUNET_CURL_Job *job;
+
+  /**
+   * Function to call with the result.
+   */
+  TALER_BANK_ConfigCallback hcb;
+
+  /**
+   * Closure for @a cb.
+   */
+  void *hcb_cls;
+};
+
+
+/**
+ * Parse configuration given in JSON format and invoke the callback on each item.
+ *
+ * @param ch handle to the account configuration request
+ * @param config JSON object with the configuration
+ * @return #GNUNET_OK if configuration was valid and @a rconfiguration and @a balance
+ *         were set,
+ *         #GNUNET_SYSERR if there was a protocol violation in @a configuration
+ */
+static int
+parse_config (struct TALER_BANK_ConfigHandle *ch,
+              const json_t *config)
+{
+  struct TALER_BANK_Configuration cfg;
+  struct GNUNET_JSON_Specification spec[] = {
+    GNUNET_JSON_spec_string ("version",
+                             &cfg.version),
+    GNUNET_JSON_spec_string ("currency",
+                             &cfg.version),
+    GNUNET_JSON_spec_end ()
+  };
+
+  if (GNUNET_OK !=
+      GNUNET_JSON_parse (config,
+                         spec,
+                         NULL, NULL))
+  {
+    GNUNET_break_op (0);
+    return GNUNET_SYSERR;
+  }
+  ch->hcb (ch->hcb_cls,
+           MHD_HTTP_OK,
+           TALER_EC_NONE,
+           &cfg);
+  GNUNET_JSON_parse_free (spec);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP /config request.
+ *
+ * @param cls the `struct TALER_BANK_ConfigHandle`
+ * @param response_code HTTP response code, 0 on error
+ * @param response parsed JSON result, NULL on error
+ */
+static void
+handle_configuration_finished (void *cls,
+                               long response_code,
+                               const void *response)
+{
+  struct TALER_BANK_ConfigHandle *ch = cls;
+  enum TALER_ErrorCode ec;
+  const json_t *j = response;
+
+  ch->job = NULL;
+  switch (response_code)
+  {
+  case 0:
+    ec = TALER_EC_INVALID_RESPONSE;
+    break;
+  case MHD_HTTP_OK:
+    if (GNUNET_OK !=
+        parse_config (ch,
+                      j))
+    {
+      GNUNET_break_op (0);
+      response_code = 0;
+      ec = TALER_EC_INVALID_RESPONSE;
+      break;
+    }
+    response_code = MHD_HTTP_NO_CONTENT; /* signal end of list */
+    ec = TALER_EC_NONE;
+    break;
+  case MHD_HTTP_BAD_REQUEST:
+    /* This should never happen, either us or the bank is buggy
+       (or API version conflict); just pass JSON reply to the application */
+    GNUNET_break_op (0);
+    ec = TALER_JSON_get_error_code (j);
+    break;
+  case MHD_HTTP_UNAUTHORIZED:
+    /* Nothing really to verify, bank says the HTTP Authentication
+       failed. May happen if HTTP authentication is used and the
+       user supplied a wrong username/password combination. */
+    ec = TALER_JSON_get_error_code (j);
+    break;
+  case MHD_HTTP_INTERNAL_SERVER_ERROR:
+    /* Server had an internal issue; we should retry, but this API
+       leaves this to the application */
+    ec = TALER_JSON_get_error_code (j);
+    break;
+  default:
+    /* unexpected response code */
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Unexpected response code %u\n",
+                (unsigned int) response_code);
+    GNUNET_break_op (0);
+    ec = TALER_JSON_get_error_code (j);
+    response_code = 0;
+    break;
+  }
+  ch->hcb (ch->hcb_cls,
+           response_code,
+           ec,
+           NULL);
+  TALER_BANK_configuration_cancel (ch);
+}
+
+
+/**
+ * Request the configuration of the bank.
+ *
+ * @param ctx curl context for the event loop
+ * @param auth authentication data to use
+ * @param hres_cb the callback to call with the
+ *        configuration
+ * @param hres_cb_cls closure for the above callback
+ * @return NULL if the inputs are invalid
+ */
+struct TALER_BANK_ConfigHandle *
+TALER_BANK_configuration (struct GNUNET_CURL_Context *ctx,
+                          const struct TALER_BANK_AuthenticationData *auth,
+                          TALER_BANK_ConfigCallback hres_cb,
+                          void *hres_cb_cls)
+{
+  struct TALER_BANK_ConfigHandle *ch;
+  CURL *eh;
+
+  ch = GNUNET_new (struct TALER_BANK_ConfigHandle);
+  ch->hcb = hres_cb;
+  ch->hcb_cls = hres_cb_cls;
+  ch->request_url = TALER_url_join (auth->wire_gateway_url,
+                                    "config",
+                                    NULL);
+  if (NULL == ch->request_url)
+  {
+    GNUNET_free (ch);
+    GNUNET_break (0);
+    return NULL;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Requesting configuration at `%s'\n",
+              ch->request_url);
+  eh = curl_easy_init ();
+  if ( (GNUNET_OK !=
+        TALER_BANK_setup_auth_ (eh,
+                                auth)) ||
+       (CURLE_OK !=
+        curl_easy_setopt (eh,
+                          CURLOPT_URL,
+                          ch->request_url)) )
+  {
+    GNUNET_break (0);
+    TALER_BANK_configuration_cancel (ch);
+    curl_easy_cleanup (eh);
+    return NULL;
+  }
+  ch->job = GNUNET_CURL_job_add2 (ctx,
+                                  eh,
+                                  NULL,
+                                  &handle_configuration_finished,
+                                  ch);
+  return ch;
+}
+
+
+/**
+ * Cancel a configuration request.  This function cannot be
+ * used on a request handle if a response is already
+ * served for it.
+ *
+ * @param ch the configuration request handle
+ */
+void
+TALER_BANK_configuration_cancel (struct TALER_BANK_ConfigHandle *ch)
+{
+  if (NULL != ch->job)
+  {
+    GNUNET_CURL_job_cancel (ch->job);
+    ch->job = NULL;
+  }
+  GNUNET_free (ch->request_url);
+  GNUNET_free (ch);
+}
+
+
+/* end of bank_api_config.c */
diff --git a/src/bank-lib/bank_api_credit.c b/src/bank-lib/bank_api_credit.c
index 50725a4ed..66e128da1 100644
--- a/src/bank-lib/bank_api_credit.c
+++ b/src/bank-lib/bank_api_credit.c
@@ -30,7 +30,7 @@
 
 
 /**
- * @brief A /history Handle
+ * @brief A /history/incoming Handle
  */
 struct TALER_BANK_CreditHistoryHandle
 {
@@ -173,30 +173,21 @@ handle_credit_history_finished (void *cls,
     GNUNET_break_op (0);
     ec = TALER_JSON_get_error_code (j);
     break;
-  case MHD_HTTP_FORBIDDEN:
-    /* Access denied */
-    GNUNET_break_op (0);
-    ec = TALER_JSON_get_error_code (j);
-    break;
   case MHD_HTTP_UNAUTHORIZED:
-    /* FIXME(dold): I don't get this comment below.  What signatures would the
-       bank even verify?! */
-    /* Nothing really to verify, bank says one of the signatures is
-       invalid; as we checked them, this should never happen, we
-       should pass the JSON reply to the application */
-    GNUNET_break_op (0);
+    /* Nothing really to verify, bank says the HTTP Authentication
+       failed. May happen if HTTP authentication is used and the
+       user supplied a wrong username/password combination. */
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_NOT_FOUND:
-    /* Nothing really to verify, this should never
-       happen, we should pass the JSON reply to the application */
-    GNUNET_break_op (0);
+    /* Nothing really to verify: the bank is either unaware
+       of the endpoint (not a bank), or of the account.
+       We should pass the JSON (?) reply to the application */
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_INTERNAL_SERVER_ERROR:
     /* Server had an internal issue; we should retry, but this API
        leaves this to the application */
-    GNUNET_break_op (0);
     ec = TALER_JSON_get_error_code (j);
     break;
   default:
diff --git a/src/bank-lib/bank_api_debit.c b/src/bank-lib/bank_api_debit.c
index 0e218eb48..58f6ae6d4 100644
--- a/src/bank-lib/bank_api_debit.c
+++ b/src/bank-lib/bank_api_debit.c
@@ -30,7 +30,7 @@
 
 
 /**
- * @brief A /history Handle
+ * @brief A /history/outgoing Handle
  */
 struct TALER_BANK_DebitHistoryHandle
 {
@@ -129,16 +129,16 @@ parse_account_history (struct TALER_BANK_DebitHistoryHandle *hh,
 
 /**
  * Function called when we're done processing the
- * HTTP /history request.
+ * HTTP /history/outgoing request.
  *
  * @param cls the `struct TALER_BANK_DebitHistoryHandle`
  * @param response_code HTTP response code, 0 on error
  * @param response parsed JSON result, NULL on error
  */
 static void
-handle_history_finished (void *cls,
-                         long response_code,
-                         const void *response)
+handle_debit_history_finished (void *cls,
+                               long response_code,
+                               const void *response)
 {
   struct TALER_BANK_DebitHistoryHandle *hh = cls;
   enum TALER_ErrorCode ec;
@@ -169,21 +169,19 @@ handle_history_finished (void *cls,
   case MHD_HTTP_BAD_REQUEST:
     /* This should never happen, either us or the bank is buggy
        (or API version conflict); just pass JSON reply to the application */
-    ec = TALER_JSON_get_error_code (j);
-    break;
-  case MHD_HTTP_FORBIDDEN:
-    /* Access denied */
+    GNUNET_break_op (0);
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_UNAUTHORIZED:
-    /* Nothing really to verify, bank says one of the signatures is
-       invalid; as we checked them, this should never happen, we
-       should pass the JSON reply to the application */
+    /* Nothing really to verify, bank says the HTTP Authentication
+       failed. May happen if HTTP authentication is used and the
+       user supplied a wrong username/password combination. */
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_NOT_FOUND:
-    /* Nothing really to verify, this should never
-       happen, we should pass the JSON reply to the application */
+    /* Nothing really to verify: the bank is either unaware
+       of the endpoint (not a bank), or of the account.
+       We should pass the JSON (?) reply to the application */
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_INTERNAL_SERVER_ERROR:
@@ -196,7 +194,7 @@ handle_history_finished (void *cls,
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "Unexpected response code %u\n",
                 (unsigned int) response_code);
-    GNUNET_break (0);
+    GNUNET_break_op (0);
     ec = TALER_JSON_get_error_code (j);
     response_code = 0;
     break;
@@ -292,7 +290,7 @@ TALER_BANK_debit_history (struct GNUNET_CURL_Context *ctx,
   hh->job = GNUNET_CURL_job_add2 (ctx,
                                   eh,
                                   NULL,
-                                  &handle_history_finished,
+                                  &handle_debit_history_finished,
                                   hh);
   return hh;
 }
diff --git a/src/bank-lib/fakebank.c b/src/bank-lib/fakebank.c
index c7e324dec..47a06c59c 100644
--- a/src/bank-lib/fakebank.c
+++ b/src/bank-lib/fakebank.c
@@ -27,6 +27,24 @@
 #include "taler_mhd_lib.h"
 
 /**
+ * Taler protocol version in the format CURRENT:REVISION:AGE
+ * as used by GNU libtool.  See
+ * https://www.gnu.org/software/libtool/manual/html_node/Libtool-versioning.html
+ *
+ * Please be very careful when updating and follow
+ * https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html#Updating-version-info
+ * precisely.  Note that this version has NOTHING to do with the
+ * release version, and the format is NOT the same that semantic
+ * versioning uses either.
+ *
+ * When changing this version, you likely want to also update
+ * #BANK_PROTOCOL_CURRENT and #BANK_PROTOCOL_AGE in
+ * bank_api_config.c!
+ */
+#define BANK_PROTOCOL_VERSION "0:0:0"
+
+
+/**
  * Maximum POST request size (for /admin/add-incoming)
  */
 #define REQUEST_BUFFER_MAX (4 * 1024)
@@ -173,6 +191,11 @@ struct TALER_FAKEBANK_Handle
   uint64_t serial_counter;
 
   /**
+   * Currency used by the fakebank.
+   */
+  char *currency;
+
+  /**
    * BaseURL of the fakebank.
    */
   char *my_baseurl;
@@ -527,6 +550,7 @@ TALER_FAKEBANK_stop (struct TALER_FAKEBANK_Handle *h)
     h->mhd_bank = NULL;
   }
   GNUNET_free (h->my_baseurl);
+  GNUNET_free (h->currency);
   GNUNET_free (h);
 }
 
@@ -776,7 +800,7 @@ handle_transfer (struct TALER_FAKEBANK_Handle *h,
 
 
 /**
- * Handle incoming HTTP request for /
+ * Handle incoming HTTP request for / (home page).
  *
  * @param h the fakebank handle
  * @param connection the connection
@@ -809,6 +833,29 @@ handle_home_page (struct TALER_FAKEBANK_Handle *h,
 
 
 /**
+ * Handle incoming HTTP request for /config
+ *
+ * @param h the fakebank handle
+ * @param connection the connection
+ * @param con_cls place to store state, not used
+ * @return MHD result code
+ */
+static int
+handle_config (struct TALER_FAKEBANK_Handle *h,
+               struct MHD_Connection *connection,
+               void **con_cls)
+{
+  return TALER_MHD_reply_json_pack (connection,
+                                    MHD_HTTP_OK,
+                                    "{s:s, s:s}",
+                                    "currency",
+                                    h->currency,
+                                    "version"
+                                    BANK_PROTOCOL_VERSION);
+}
+
+
+/**
  * This is the "base" structure for both the /history and the
  * /history-range API calls.
  */
@@ -1221,6 +1268,13 @@ serve (struct TALER_FAKEBANK_Handle *h,
                              connection,
                              con_cls);
   if ( (0 == strcmp (url,
+                     "/config")) &&
+       (0 == strcasecmp (method,
+                         MHD_HTTP_METHOD_GET)) )
+    return handle_config (h,
+                          connection,
+                          con_cls);
+  if ( (0 == strcmp (url,
                      "/admin/add-incoming")) &&
        (0 == strcasecmp (method,
                          MHD_HTTP_METHOD_POST)) )
@@ -1451,15 +1505,19 @@ run_mhd (void *cls)
  * would have issued the correct wire transfer orders.
  *
  * @param port port to listen to
+ * @param currency currency the bank uses
  * @return NULL on error
  */
 struct TALER_FAKEBANK_Handle *
-TALER_FAKEBANK_start (uint16_t port)
+TALER_FAKEBANK_start (uint16_t port,
+                      const char *currency)
 {
   struct TALER_FAKEBANK_Handle *h;
 
+  GNUNET_assert (strlen (currency) < TALER_CURRENCY_LEN);
   h = GNUNET_new (struct TALER_FAKEBANK_Handle);
   h->port = port;
+  h->currency = GNUNET_strdup (currency);
   GNUNET_asprintf (&h->my_baseurl,
                    "http://localhost:%u/",
                    (unsigned int) port);
@@ -1480,6 +1538,7 @@ TALER_FAKEBANK_start (uint16_t port)
                                   MHD_OPTION_END);
   if (NULL == h->mhd_bank)
   {
+    GNUNET_free (h->currency);
     GNUNET_free (h);
     return NULL;
   }
diff --git a/src/bank-lib/taler-fakebank-run.c b/src/bank-lib/taler-fakebank-run.c
index 55b3da54f..588777c94 100644
--- a/src/bank-lib/taler-fakebank-run.c
+++ b/src/bank-lib/taler-fakebank-run.c
@@ -43,12 +43,38 @@ run (void *cls,
      const char *cfgfile,
      const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
+  char *currency_string;
+
   (void) cls;
   (void) args;
   (void) cfgfile;
   (void) cfg;
-  if (NULL == TALER_FAKEBANK_start (8082))
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "taler",
+                                             "CURRENCY",
+                                             &currency_string))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "taler",
+                               "CURRENCY");
+    ret = 1;
+    return;
+  }
+  if (strlen (currency_string) >= TALER_CURRENCY_LEN)
+  {
+    GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
+                               "taler",
+                               "CURRENCY",
+                               "Value is too long");
+    GNUNET_free (currency_string);
+    ret = 1;
+    return;
+  }
+  if (NULL == TALER_FAKEBANK_start (8082,
+                                    currency_string))
     ret = 1;
+  GNUNET_free (currency_string);
   ret = 0;
 }
 
diff --git a/src/benchmark/taler-exchange-benchmark.c b/src/benchmark/taler-exchange-benchmark.c
index bd4d3eafe..91ed5b047 100644
--- a/src/benchmark/taler-exchange-benchmark.c
+++ b/src/benchmark/taler-exchange-benchmark.c
@@ -156,9 +156,9 @@ static char *mode_str;
 static enum BenchmarkMode mode;
 
 /**
- * Config filename.
+ * Configuration.
  */
-static char *cfg_filename;
+static struct GNUNET_CONFIGURATION_Handle *cfg;
 
 /**
  * Currency used.
@@ -445,7 +445,8 @@ launch_fakebank (void *cls)
 
   (void) cls;
   fakebank
-    = TALER_TESTING_run_fakebank (exchange_bank_account.wire_gateway_url);
+    = TALER_TESTING_run_fakebank (exchange_bank_account.wire_gateway_url,
+                                  currency);
   if (NULL == fakebank)
   {
     GNUNET_break (0);
@@ -624,12 +625,11 @@ parallel_benchmark (TALER_TESTING_Main main_cb,
                           NULL == loglev ? "INFO" : loglev,
                           logfile);
 
-        result = TALER_TESTING_setup
-                   (main_cb,
-                   main_cb_cls,
-                   cfg_filename,
-                   exchanged,
-                   GNUNET_YES);
+        result = TALER_TESTING_setup (main_cb,
+                                      main_cb_cls,
+                                      cfg,
+                                      exchanged,
+                                      GNUNET_YES);
         if (GNUNET_OK != result)
           GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                       "Failure in child process test suite!\n");
@@ -746,7 +746,7 @@ int
 main (int argc,
       char *const *argv)
 {
-  struct GNUNET_CONFIGURATION_Handle *cfg;
+  char *cfg_filename = NULL;
   struct GNUNET_GETOPT_CommandLineOption options[] = {
     GNUNET_GETOPT_option_mandatory
       (GNUNET_GETOPT_option_cfgfile (&cfg_filename)),
@@ -798,6 +798,7 @@ main (int argc,
                                    argc,
                                    argv)))
   {
+    GNUNET_free_non_null (cfg_filename);
     return BAD_CLI_ARG;
   }
   GNUNET_log_setup ("taler-exchange-benchmark",
@@ -814,6 +815,7 @@ main (int argc,
   else
   {
     TALER_LOG_ERROR ("Unknown mode given: '%s'\n", mode_str);
+    GNUNET_free_non_null (cfg_filename);
     return BAD_CONFIG_FILE;
   }
   if (NULL == cfg_filename)
@@ -825,8 +827,10 @@ main (int argc,
                                  cfg_filename))
   {
     TALER_LOG_ERROR ("Could not parse configuration\n");
+    GNUNET_free (cfg_filename);
     return BAD_CONFIG_FILE;
   }
+  GNUNET_free (cfg_filename);
   if (GNUNET_OK !=
       GNUNET_CONFIGURATION_get_value_string (cfg,
                                              "taler",
@@ -839,6 +843,16 @@ main (int argc,
     GNUNET_CONFIGURATION_destroy (cfg);
     return BAD_CONFIG_FILE;
   }
+
+  if (strlen (currency) >= TALER_CURRENCY_LEN)
+  {
+    GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
+                               "taler",
+                               "CURRENCY",
+                               "Value is too long");
+    GNUNET_CONFIGURATION_destroy (cfg);
+    return BAD_CONFIG_FILE;
+  }
   if (howmany_clients > 10240)
   {
     TALER_LOG_ERROR ("-p option value given is too large\n");
@@ -950,11 +964,11 @@ main (int argc,
       return BAD_CONFIG_FILE;
     }
   }
-  GNUNET_CONFIGURATION_destroy (cfg);
 
   result = parallel_benchmark (&run,
                                NULL,
                                cfg_filename);
+  GNUNET_CONFIGURATION_destroy (cfg);
 
   /* If we're the exchange worker, we're done now.  No need to print results */
   if (MODE_EXCHANGE == mode)
diff --git a/src/exchange-tools/taler-exchange-keyup.c b/src/exchange-tools/taler-exchange-keyup.c
index 33039c3d1..a11ec3f89 100644
--- a/src/exchange-tools/taler-exchange-keyup.c
+++ b/src/exchange-tools/taler-exchange-keyup.c
@@ -1437,6 +1437,8 @@ main (int argc,
                                       "DKH",
                                       "revoke denomination key hash (DKH) and request wallets to initiate /recoup",
                                       &revoke_dkh),
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
     GNUNET_GETOPT_option_absolute_time ('t',
                                         "time",
                                         "TIMESTAMP",
diff --git a/src/exchange-tools/taler-exchange-wire.c b/src/exchange-tools/taler-exchange-wire.c
index 5ddc24040..0d6cdddbf 100644
--- a/src/exchange-tools/taler-exchange-wire.c
+++ b/src/exchange-tools/taler-exchange-wire.c
@@ -228,6 +228,8 @@ main (int argc,
       char *const *argv)
 {
   const struct GNUNET_GETOPT_CommandLineOption options[] = {
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
     GNUNET_GETOPT_option_filename ('m',
                                    "master-key",
                                    "FILENAME",
diff --git a/src/exchange/Makefile.am b/src/exchange/Makefile.am
index 50eb545b0..cf9f984de 100644
--- a/src/exchange/Makefile.am
+++ b/src/exchange/Makefile.am
@@ -83,7 +83,8 @@ taler_exchange_httpd_LDADD = \
 AM_TESTS_ENVIRONMENT=export TALER_PREFIX=$${TALER_PREFIX:-@libdir@};export PATH=$${TALER_PREFIX:-@prefix@}/bin:$$PATH;
 
 check_SCRIPTS = \
-  test_taler_exchange_httpd.sh
+  test_taler_exchange_httpd.sh \
+  test_taler_exchange_httpd_restart.sh
 if HAVE_EXPENSIVE_TESTS
 check_SCRIPTS += \
   test_taler_exchange_httpd_afl.sh
@@ -97,6 +98,7 @@ TESTS = \
 EXTRA_DIST = \
   test_taler_exchange_httpd_home/.local/share/taler/exchange/offline-keys/master.priv \
   test_taler_exchange_httpd.conf \
+  test_taler_exchange_unix.conf \
   test_taler_exchange_httpd.get \
   test_taler_exchange_httpd.post \
   exchange.conf \
diff --git a/src/exchange/taler-exchange-aggregator.c b/src/exchange/taler-exchange-aggregator.c
index a43277b23..d380c3915 100644
--- a/src/exchange/taler-exchange-aggregator.c
+++ b/src/exchange/taler-exchange-aggregator.c
@@ -582,6 +582,7 @@ shutdown_task (void *cls)
     ctc = NULL;
   }
   TALER_EXCHANGEDB_plugin_unload (db_plugin);
+  db_plugin = NULL;
 
   {
     struct WireAccount *wa;
@@ -670,6 +671,7 @@ parse_wirewatch_config ()
     fprintf (stderr,
              "Failed to initialize DB tables\n");
     TALER_EXCHANGEDB_plugin_unload (db_plugin);
+    db_plugin = NULL;
     return GNUNET_SYSERR;
   }
   TALER_EXCHANGEDB_find_accounts (cfg,
@@ -680,6 +682,7 @@ parse_wirewatch_config ()
     fprintf (stderr,
              "No wire accounts configured for debit!\n");
     TALER_EXCHANGEDB_plugin_unload (db_plugin);
+    db_plugin = NULL;
     return GNUNET_SYSERR;
   }
   return GNUNET_OK;
@@ -1179,10 +1182,9 @@ expired_reserve_cb (void *cls,
     /* Reserve balance was almost zero OR soft error */
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
                 "Reserve was virtually empty, moving on\n");
-    (void) commit_or_warn (ctc->session);
-    GNUNET_free (ctc->method);
-    GNUNET_free (ctc);
-    ctc = NULL;
+    (void) commit_or_warn (session);
+    erc->async_cont = GNUNET_YES;
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_transfers,
                                      NULL);
     return qs;
@@ -1223,6 +1225,7 @@ expired_reserve_cb (void *cls,
     return GNUNET_DB_STATUS_SUCCESS_NO_RESULTS;
   }
   erc->async_cont = GNUNET_YES;
+  GNUNET_assert (NULL == task);
   task = GNUNET_SCHEDULER_add_now (&run_transfers,
                                    NULL);
   GNUNET_free (ctc->method);
@@ -1299,6 +1302,7 @@ run_reserve_closures (void *cls)
   case GNUNET_DB_STATUS_SOFT_ERROR:
     db_plugin->rollback (db_plugin->cls,
                          session);
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_reserve_closures,
                                      NULL);
     return;
@@ -1308,6 +1312,7 @@ run_reserve_closures (void *cls)
     reserves_idle = GNUNET_YES;
     db_plugin->rollback (db_plugin->cls,
                          session);
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1315,6 +1320,7 @@ run_reserve_closures (void *cls)
     (void) commit_or_warn (session);
     if (GNUNET_YES == erc.async_cont)
       break;
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_reserve_closures,
                                      NULL);
     return;
@@ -1345,6 +1351,7 @@ run_aggregation (void *cls)
     return;
   if (0 == (++swap % 2))
   {
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_reserve_closures,
                                      NULL);
     return;
@@ -1392,6 +1399,7 @@ run_aggregation (void *cls)
     {
       /* should re-try immediately */
       swap--; /* do not count failed attempts */
+      GNUNET_assert (NULL == task);
       task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                        NULL);
       return;
@@ -1408,15 +1416,21 @@ run_aggregation (void *cls)
     {
       if ( (GNUNET_NO == reserves_idle) ||
            (GNUNET_YES == test_mode) )
+      {
         /* Possibly more to on reserves, go for it immediately */
+        GNUNET_assert (NULL == task);
         task = GNUNET_SCHEDULER_add_now (&run_reserve_closures,
                                          NULL);
+      }
       else
+      {
         /* FIXME(dold): We might want to read the duration to sleep from the config */
         /* nothing to do, sleep for a minute and try again */
+        GNUNET_assert (NULL == task);
         task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
                                              &run_aggregation,
                                              NULL);
+      }
     }
     return;
   }
@@ -1451,6 +1465,7 @@ run_aggregation (void *cls)
                 "Serialization issue, trying again later!\n");
     db_plugin->rollback (db_plugin->cls,
                          session);
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1515,6 +1530,7 @@ run_aggregation (void *cls)
                            session);
       cleanup_au ();
       /* start again */
+      GNUNET_assert (NULL == task);
       task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                        NULL);
       return;
@@ -1531,6 +1547,7 @@ run_aggregation (void *cls)
     (void) commit_or_warn (session);
     cleanup_au ();
     /* start again */
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1587,6 +1604,7 @@ run_aggregation (void *cls)
     db_plugin->rollback (db_plugin->cls,
                          session);
     /* start again */
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1613,6 +1631,7 @@ run_aggregation (void *cls)
     /* try again */
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                 "Commit issue for prepared wire data; trying again later!\n");
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1625,6 +1644,7 @@ run_aggregation (void *cls)
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
                 "Preparation complete, switching to transfer mode\n");
     /* run alternative task: actually do wire transfer! */
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_transfers,
                                      NULL);
     return;
@@ -1685,6 +1705,7 @@ wire_confirm_cb (void *cls,
     if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
     {
       /* try again */
+      GNUNET_assert (NULL == task);
       task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                        NULL);
     }
@@ -1703,6 +1724,7 @@ wire_confirm_cb (void *cls,
   {
   case GNUNET_DB_STATUS_SOFT_ERROR:
     /* try again */
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1716,6 +1738,7 @@ wire_confirm_cb (void *cls,
                 "Wire transfer complete\n");
     /* continue with #run_transfers(), just to guard
        against the unlikely case that there are more. */
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_transfers,
                                      NULL);
     return;
@@ -1846,6 +1869,7 @@ run_transfers (void *cls)
     return;
   case GNUNET_DB_STATUS_SOFT_ERROR:
     /* try again */
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_transfers,
                                      NULL);
     return;
@@ -1853,6 +1877,7 @@ run_transfers (void *cls)
     /* no more prepared wire transfers, go back to aggregation! */
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
                 "No more pending wire transfers, starting aggregation\n");
+    GNUNET_assert (NULL == task);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
                                      NULL);
     return;
@@ -1898,6 +1923,7 @@ run (void *cls,
     return;
   }
 
+  GNUNET_assert (NULL == task);
   task = GNUNET_SCHEDULER_add_now (&run_transfers,
                                    NULL);
   GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
@@ -1917,6 +1943,8 @@ main (int argc,
       char *const *argv)
 {
   struct GNUNET_GETOPT_CommandLineOption options[] = {
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
     GNUNET_GETOPT_option_flag ('t',
                                "test",
                                "run in test mode and exit when idle",
diff --git a/src/exchange/taler-exchange-httpd.c b/src/exchange/taler-exchange-httpd.c
index 666cec0c1..426c48655 100644
--- a/src/exchange/taler-exchange-httpd.c
+++ b/src/exchange/taler-exchange-httpd.c
@@ -999,6 +999,8 @@ main (int argc,
                                "SECONDS",
                                "after how long do connections timeout by default (in seconds)",
                                &connection_timeout),
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
 #if HAVE_DEVELOPER
     GNUNET_GETOPT_option_filename ('f',
                                    "file-input",
diff --git a/src/exchange/taler-exchange-httpd_mhd.c b/src/exchange/taler-exchange-httpd_mhd.c
index 53944b6a7..0f2ce033a 100644
--- a/src/exchange/taler-exchange-httpd_mhd.c
+++ b/src/exchange/taler-exchange-httpd_mhd.c
@@ -128,11 +128,10 @@ TEH_MHD_handler_send_json_pack_error (struct TEH_RequestHandler *rh,
   (void) connection_cls;
   (void) upload_data;
   (void) upload_data_size;
-  return TALER_MHD_reply_json_pack (connection,
-                                    rh->response_code,
-                                    "{s:s}",
-                                    "error",
-                                    rh->data);
+  return TALER_MHD_reply_with_error (connection,
+                                     rh->response_code,
+                                     TALER_EC_METHOD_INVALID,
+                                     rh->data);
 }
 
 
diff --git a/src/exchange/taler-exchange-httpd_refresh_melt.c b/src/exchange/taler-exchange-httpd_refresh_melt.c
index 71200037d..c7dc700f7 100644
--- a/src/exchange/taler-exchange-httpd_refresh_melt.c
+++ b/src/exchange/taler-exchange-httpd_refresh_melt.c
@@ -69,7 +69,7 @@ reply_refresh_melt_insufficient_funds (struct MHD_Connection *connection,
   return TALER_MHD_reply_json_pack (connection,
                                     MHD_HTTP_CONFLICT,
                                     "{s:s, s:I, s:o, s:o, s:o, s:o, s:o}",
-                                    "error",
+                                    "hint",
                                     "insufficient funds",
                                     "code",
                                     (json_int_t)
diff --git a/src/exchange/taler-exchange-httpd_refresh_reveal.c b/src/exchange/taler-exchange-httpd_refresh_reveal.c
index bbafdd1a1..6ac91caf8 100644
--- a/src/exchange/taler-exchange-httpd_refresh_reveal.c
+++ b/src/exchange/taler-exchange-httpd_refresh_reveal.c
@@ -108,7 +108,7 @@ reply_refresh_reveal_mismatch (struct MHD_Connection *connection,
   return TALER_MHD_reply_json_pack (connection,
                                     MHD_HTTP_CONFLICT,
                                     "{s:s, s:I, s:o}",
-                                    "error", "commitment violation",
+                                    "hint", "commitment violation",
                                     "code",
                                     (json_int_t)
                                     TALER_EC_REFRESH_REVEAL_COMMITMENT_VIOLATION,
diff --git a/src/exchange/taler-exchange-httpd_refund.c b/src/exchange/taler-exchange-httpd_refund.c
index 8c6e90302..8e24b9b47 100644
--- a/src/exchange/taler-exchange-httpd_refund.c
+++ b/src/exchange/taler-exchange-httpd_refund.c
@@ -83,28 +83,6 @@ reply_refund_success (struct MHD_Connection *connection,
 
 
 /**
- * Generate generic refund failure message. All the details
- * are in the @a response_code.  The body can be empty.
- *
- * @param connection connection to the client
- * @param response_code response code to generate
- * @param ec taler error code to include
- * @return MHD result code
- */
-static int
-reply_refund_failure (struct MHD_Connection *connection,
-                      unsigned int response_code,
-                      enum TALER_ErrorCode ec)
-{
-  return TALER_MHD_reply_json_pack (connection,
-                                    response_code,
-                                    "{s:s, s:I}",
-                                    "hint", "refund failure",
-                                    "code", (json_int_t) ec);
-}
-
-
-/**
  * Generate refund conflict failure message. Returns the
  * transaction list @a tl with the details about the conflict.
  *
@@ -194,9 +172,10 @@ refund_transaction (void *cls,
   if (0 > qs)
   {
     if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-      *mhd_ret = reply_refund_failure (connection,
-                                       MHD_HTTP_NOT_FOUND,
-                                       TALER_EC_REFUND_COIN_NOT_FOUND);
+      *mhd_ret = TALER_MHD_reply_with_error (connection,
+                                             MHD_HTTP_NOT_FOUND,
+                                             TALER_EC_REFUND_COIN_NOT_FOUND,
+                                             "database transaction failure");
     return qs;
   }
   deposit_found = GNUNET_NO;
@@ -319,9 +298,10 @@ refund_transaction (void *cls,
     GNUNET_break_op (0); /* currency mismatch */
     TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
                                             tl);
-    *mhd_ret = reply_refund_failure (connection,
-                                     MHD_HTTP_PRECONDITION_FAILED,
-                                     TALER_EC_REFUND_CURRENCY_MISSMATCH);
+    *mhd_ret = TALER_MHD_reply_with_error (connection,
+                                           MHD_HTTP_PRECONDITION_FAILED,
+                                           TALER_EC_REFUND_CURRENCY_MISSMATCH,
+                                           "currencies involved do not match");
     return GNUNET_DB_STATUS_HARD_ERROR;
   }
 
@@ -353,9 +333,10 @@ refund_transaction (void *cls,
     /* money was already transferred to merchant, can no longer refund */
     TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
                                             tl);
-    *mhd_ret = reply_refund_failure (connection,
-                                     MHD_HTTP_GONE,
-                                     TALER_EC_REFUND_MERCHANT_ALREADY_PAID);
+    *mhd_ret = TALER_MHD_reply_with_error (connection,
+                                           MHD_HTTP_GONE,
+                                           TALER_EC_REFUND_MERCHANT_ALREADY_PAID,
+                                           "money already sent to merchant");
     return GNUNET_DB_STATUS_HARD_ERROR;
   }
 
@@ -366,9 +347,10 @@ refund_transaction (void *cls,
     GNUNET_break_op (0); /* cannot refund more than original value */
     TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
                                             tl);
-    *mhd_ret = reply_refund_failure (connection,
-                                     MHD_HTTP_PRECONDITION_FAILED,
-                                     TALER_EC_REFUND_INSUFFICIENT_FUNDS);
+    *mhd_ret = TALER_MHD_reply_with_error (connection,
+                                           MHD_HTTP_PRECONDITION_FAILED,
+                                           TALER_EC_REFUND_INSUFFICIENT_FUNDS,
+                                           "refund requested exceeds original value");
     return GNUNET_DB_STATUS_HARD_ERROR;
   }
   /* Check refund fee matches fee of denomination key! */
@@ -481,9 +463,10 @@ verify_and_execute_refund (struct MHD_Connection *connection,
     if (0 > qs)
     {
       GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
-      return reply_refund_failure (connection,
-                                   MHD_HTTP_NOT_FOUND,
-                                   TALER_EC_REFUND_COIN_NOT_FOUND);
+      return TALER_MHD_reply_with_error (connection,
+                                         MHD_HTTP_NOT_FOUND,
+                                         TALER_EC_REFUND_COIN_NOT_FOUND,
+                                         "denomination of coin to be refunded not found in DB");
     }
   }
 
diff --git a/src/exchange/taler-exchange-httpd_reserve_status.c b/src/exchange/taler-exchange-httpd_reserve_status.c
index 89bf8b38a..e2d35aaec 100644
--- a/src/exchange/taler-exchange-httpd_reserve_status.c
+++ b/src/exchange/taler-exchange-httpd_reserve_status.c
@@ -164,7 +164,7 @@ TEH_RESERVE_handler_reserve_status (struct TEH_RequestHandler *rh,
     return TALER_MHD_reply_json_pack (connection,
                                       MHD_HTTP_NOT_FOUND,
                                       "{s:s, s:s, s:I}",
-                                      "error", "Reserve not found",
+                                      "hint", "Reserve not found",
                                       "parameter", "reserve_pub",
                                       "code",
                                       (json_int_t)
diff --git a/src/exchange/taler-exchange-httpd_reserve_withdraw.c b/src/exchange/taler-exchange-httpd_reserve_withdraw.c
index 86633cd98..9daad0a02 100644
--- a/src/exchange/taler-exchange-httpd_reserve_withdraw.c
+++ b/src/exchange/taler-exchange-httpd_reserve_withdraw.c
@@ -74,7 +74,7 @@ reply_reserve_withdraw_insufficient_funds (struct MHD_Connection *connection,
   return TALER_MHD_reply_json_pack (connection,
                                     MHD_HTTP_CONFLICT,
                                     "{s:s, s:I, s:o, s:o}",
-                                    "error", "Insufficient funds",
+                                    "hint", "insufficient funds",
                                     "code",
                                     (json_int_t)
                                     TALER_EC_WITHDRAW_INSUFFICIENT_FUNDS,
diff --git a/src/exchange/taler-exchange-httpd_responses.c b/src/exchange/taler-exchange-httpd_responses.c
index c88a8a254..90ca14c88 100644
--- a/src/exchange/taler-exchange-httpd_responses.c
+++ b/src/exchange/taler-exchange-httpd_responses.c
@@ -446,7 +446,7 @@ TEH_RESPONSE_reply_coin_insufficient_funds (struct MHD_Connection *connection,
   return TALER_MHD_reply_json_pack (connection,
                                     MHD_HTTP_CONFLICT,
                                     "{s:s, s:I, s:o}",
-                                    "error", "insufficient funds",
+                                    "hint", "insufficient funds",
                                     "code", (json_int_t) ec,
                                     "history", history);
 }
diff --git a/src/exchange/taler-exchange-wirewatch.c b/src/exchange/taler-exchange-wirewatch.c
index 21d96668b..69929e127 100644
--- a/src/exchange/taler-exchange-wirewatch.c
+++ b/src/exchange/taler-exchange-wirewatch.c
@@ -340,7 +340,7 @@ history_cb (void *cls,
     hh = NULL;
     if (TALER_EC_NONE != ec)
     {
-      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                   "Error fetching history: ec=%u, http_status=%u\n",
                   (unsigned int) ec,
                   http_status);
@@ -597,7 +597,9 @@ main (int argc,
       char *const *argv)
 {
   struct GNUNET_GETOPT_CommandLineOption options[] = {
-    GNUNET_GETOPT_option_flag ('T',
+    GNUNET_GETOPT_option_timetravel ('T',
+                                     "timetravel"),
+    GNUNET_GETOPT_option_flag ('t',
                                "test",
                                "run in test mode and exit when idle",
                                &test_mode),
diff --git a/src/exchange/test_taler_exchange_httpd_restart.sh b/src/exchange/test_taler_exchange_httpd_restart.sh
new file mode 100755
index 000000000..f7d7a3050
--- /dev/null
+++ b/src/exchange/test_taler_exchange_httpd_restart.sh
@@ -0,0 +1,114 @@
+#!/bin/bash
+#
+# This file is part of TALER
+# Copyright (C) 2020 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
+#  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 Affero General Public License for more details.
+#
+#  You should have received a copy of the GNU Affero General Public License along with
+#  TALER; see the file COPYING.  If not, If not, see <http://www.gnu.org/licenses/>
+#
+#
+# This script launches an exchange (binding to a UNIX domain socket) and then
+# restarts it in various ways (SIGHUP to re-read configuration, and SIGUSR1 to
+# re-spawn a new binary).  Basically, the goal is to make sure that the HTTP
+# server survives these less common operations.
+#
+#
+set -eu
+
+# Exit, with status code "skip" (no 'real' failure)
+function exit_skip() {
+    echo $1
+    exit 77
+}
+
+# Exit, with error message (hard failure)
+function exit_fail() {
+    echo $1
+    kill `jobs -p` >/dev/null 2>/dev/null || true
+    wait
+    exit 1
+}
+
+echo -n "Testing for curl"
+curl --version >/dev/null </dev/null || exit_skip " MISSING"
+echo " FOUND"
+
+
+# Clear environment from variables that override config.
+unset XDG_DATA_HOME
+unset XDG_CONFIG_HOME
+#
+echo -n "Launching exchange ..."
+PREFIX=
+# Uncomment this line to run with valgrind...
+# PREFIX="valgrind --trace-children=yes --leak-check=yes --track-fds=yes --error-exitcode=1 --log-file=valgrind.%p"
+
+# Setup keys.
+taler-exchange-keyup -c test_taler_exchange_unix.conf || exit 1
+# Setup wire accounts.
+taler-exchange-wire -c test_taler_exchange_unix.conf > /dev/null || exit 1
+# Run Exchange HTTPD (in background)
+$PREFIX taler-exchange-httpd -c test_taler_exchange_unix.conf -i 2> test-exchange.log &
+
+# Where should we be bound to?
+UNIXPATH=`taler-config -s exchange -f -o UNIXPATH`
+
+# Give HTTP time to start
+
+for n in `seq 1 100`
+do
+    echo -n "."
+    sleep 0.1
+    OK=1
+    curl --unix-socket "${UNIXPATH}" "http://ignored/" >/dev/null 2> /dev/null && break
+    OK=0
+done
+if [ 1 != $OK ]
+then
+    exit_fail "Failed to launch exchange"
+fi
+echo " DONE"
+
+# Finally run test...
+echo -n "Reloading keys ..."
+kill -SIGUSR1 $!
+sleep 1
+curl --unix-socket "${UNIXPATH}" "http://ignored/" >/dev/null 2> /dev/null || exit_fail "SIGUSR1 killed HTTP service"
+echo " DONE"
+
+# Finally run test...
+echo -n "Restarting program ..."
+kill -SIGHUP $!
+sleep 1
+curl --unix-socket "${UNIXPATH}" "http://ignored/" >/dev/null 2> /dev/null || exit_fail "SIGHUP killed HTTP service"
+echo " DONE"
+
+echo -n "Waiting for parent to die ..."
+wait $!
+echo " DONE"
+
+echo -n "Testing child still alive ..."
+curl --unix-socket "${UNIXPATH}" "http://ignored/" >/dev/null 2> /dev/null || exit_fail "SIGHUP killed HTTP service"
+echo " DONE"
+
+
+echo -n "Killing grandchild ..."
+CPID=`ps x | grep taler-exchange-httpd | grep -v grep | awk '{print $1}'`
+kill -TERM $CPID
+while true
+do
+    ps x | grep -v grep | grep taler-exchange-httpd > /dev/null || break
+    sleep 0.1
+done
+echo " DONE"
+
+# Return status code from exchange for this script
+exit 0
diff --git a/src/exchange/test_taler_exchange_unix.conf b/src/exchange/test_taler_exchange_unix.conf
new file mode 100644
index 000000000..d41df9abe
--- /dev/null
+++ b/src/exchange/test_taler_exchange_unix.conf
@@ -0,0 +1,137 @@
+[PATHS]
+# Persistant data storage for the testcase
+TALER_TEST_HOME = test_taler_exchange_httpd_home/
+
+[taler]
+# Currency supported by the exchange (can only be one)
+CURRENCY = EUR
+CURRENCY_ROUND_UNIT = EUR:0.01
+
+[exchange]
+
+# Directory with our terms of service.
+TERMS_DIR = ../../contrib/tos
+
+# Etag / filename for the terms of service.
+TERMS_ETAG = 0
+
+
+# Directory with our privacy policy.
+PRIVACY_DIR = ../../contrib/pp
+
+# Etag / filename for the privacy policy.
+PRIVACY_ETAG = 0
+
+# MAX_REQUESTS = 2
+# how long is one signkey valid?
+SIGNKEY_DURATION = 4 weeks
+
+# how long are the signatures with the signkey valid?
+LEGAL_DURATION = 2 years
+
+# how long do we generate denomination and signing keys
+# ahead of time?
+LOOKAHEAD_SIGN = 32 weeks 1 day
+
+# how long do we provide to clients denomination and signing keys
+# ahead of time?
+LOOKAHEAD_PROVIDE = 4 weeks 1 day
+
+# HTTP port the exchange listens to (we want to use UNIX domain sockets,
+# so we use a port that just won't work on GNU/Linux without root rights)
+PORT = 999
+
+# Here we say we want to use a UNIX domain socket (to test that logic).
+SERVE = unix
+
+# Master public key used to sign the exchange's various keys
+MASTER_PUBLIC_KEY = 98NJW3CQHZQGQXTY3K85K531XKPAPAVV4Q5V8PYYRR00NJGZWNVG
+
+# How to access our database
+DB = postgres
+
+
+[exchangedb]
+# After how long do we close idle reserves?  The exchange
+# and the auditor must agree on this value.  We currently
+# expect it to be globally defined for the whole system,
+# as there is no way for wallets to query this value.  Thus,
+# it is only configurable for testing, and should be treated
+# as constant in production.
+IDLE_RESERVE_EXPIRATION_TIME = 4 weeks
+
+
+[exchangedb-postgres]
+CONFIG = "postgres:///talercheck"
+
+[exchange-account-1]
+PAYTO_URI = "payto://x-taler-bank/localhost:8082/3"
+WIRE_RESPONSE = ${TALER_CONFIG_HOME}/account-1.json
+ENABLE_DEBIT = YES
+ENABLE_CREDIT = YES
+TALER_BANK_AUTH_METHOD = NONE
+
+
+# Wire fees are specified by wire method
+[fees-x-taler-bank]
+# Fees for the forseeable future...
+# If you see this after 2018, update to match the next 10 years...
+WIRE-FEE-2018 = EUR:0.01
+WIRE-FEE-2019 = EUR:0.01
+WIRE-FEE-2020 = EUR:0.01
+WIRE-FEE-2021 = EUR:0.01
+WIRE-FEE-2022 = EUR:0.01
+WIRE-FEE-2023 = EUR:0.01
+WIRE-FEE-2024 = EUR:0.01
+WIRE-FEE-2025 = EUR:0.01
+WIRE-FEE-2026 = EUR:0.01
+WIRE-FEE-2027 = EUR:0.01
+
+CLOSING-FEE-2018 = EUR:0.01
+CLOSING-FEE-2019 = EUR:0.01
+CLOSING-FEE-2020 = EUR:0.01
+CLOSING-FEE-2021 = EUR:0.01
+CLOSING-FEE-2022 = EUR:0.01
+CLOSING-FEE-2023 = EUR:0.01
+CLOSING-FEE-2024 = EUR:0.01
+CLOSING-FEE-2025 = EUR:0.01
+CLOSING-FEE-2026 = EUR:0.01
+CLOSING-FEE-2027 = EUR:0.01
+
+
+# Coins for the tests.
+[coin_eur_ct_1]
+value = EUR:0.01
+duration_overlap = 5 minutes
+duration_withdraw = 7 days
+duration_spend = 2 years
+duration_legal = 3 years
+fee_withdraw = EUR:0.00
+fee_deposit = EUR:0.00
+fee_refresh = EUR:0.01
+fee_refund = EUR:0.01
+rsa_keysize = 1024
+
+[coin_eur_ct_10]
+value = EUR:0.10
+duration_overlap = 5 minutes
+duration_withdraw = 7 days
+duration_spend = 2 years
+duration_legal = 3 years
+fee_withdraw = EUR:0.01
+fee_deposit = EUR:0.01
+fee_refresh = EUR:0.03
+fee_refund = EUR:0.01
+rsa_keysize = 1024
+
+[coin_eur_1]
+value = EUR:1
+duration_overlap = 5 minutes
+duration_withdraw = 7 days
+duration_spend = 2 years
+duration_legal = 3 years
+fee_withdraw = EUR:0.01
+fee_deposit = EUR:0.01
+fee_refresh = EUR:0.03
+fee_refund = EUR:0.01
+rsa_keysize = 1024
diff --git a/src/exchangedb/Makefile.am b/src/exchangedb/Makefile.am
index e7ac4d719..37809f6b4 100644
--- a/src/exchangedb/Makefile.am
+++ b/src/exchangedb/Makefile.am
@@ -15,8 +15,8 @@ pkgcfg_DATA = \
 sqldir = $(prefix)/share/taler/sql/exchange/
 
 sql_DATA = \
-  0000.sql \
-  0001.sql \
+  exchange-0000.sql \
+  exchange-0001.sql \
   drop0000.sql
 
 EXTRA_DIST = \
diff --git a/src/exchangedb/0000.sql b/src/exchangedb/exchange-0000.sql
index 1483e2015..1483e2015 100644
--- a/src/exchangedb/0000.sql
+++ b/src/exchangedb/exchange-0000.sql
diff --git a/src/exchangedb/0001.sql b/src/exchangedb/exchange-0001.sql
index 8e7ea0bf5..02dc68cf4 100644
--- a/src/exchangedb/0001.sql
+++ b/src/exchangedb/exchange-0001.sql
@@ -42,7 +42,7 @@ CREATE TABLE IF NOT EXISTS denominations
   ,fee_refund_val INT8 NOT NULL
   ,fee_refund_frac INT4 NOT NULL
   );
-CREATE INDEX denominations_expire_legal_index
+CREATE INDEX IF NOT EXISTS denominations_expire_legal_index
   ON denominations
   (expire_legal);
 
@@ -65,18 +65,18 @@ CREATE TABLE IF NOT EXISTS reserves
   ,gc_date INT8 NOT NULL
   );
 -- index on reserves table (TODO: useless due to primary key!?)
-CREATE INDEX reserves_reserve_pub_index
+CREATE INDEX IF NOT EXISTS reserves_reserve_pub_index
   ON reserves
   (reserve_pub);
 -- index for get_expired_reserves
-CREATE INDEX reserves_expiration_index
+CREATE INDEX IF NOT EXISTS reserves_expiration_index
   ON reserves
   (expiration_date
   ,current_balance_val
   ,current_balance_frac
   );
 -- index for reserve GC operations
-CREATE INDEX reserves_gc_index
+CREATE INDEX IF NOT EXISTS reserves_gc_index
   ON reserves
   (gc_date);
 -- reserves_in table collects the transactions which transfer funds
@@ -94,12 +94,12 @@ CREATE TABLE IF NOT EXISTS reserves_in
   ,PRIMARY KEY (reserve_pub, wire_reference)
   );
 -- Create indices on reserves_in
-CREATE INDEX reserves_in_execution_index
+CREATE INDEX IF NOT EXISTS reserves_in_execution_index
   ON reserves_in
   (exchange_account_section
   ,execution_date
   );
-CREATE INDEX reserves_in_exchange_account_serial
+CREATE INDEX IF NOT EXISTS reserves_in_exchange_account_serial
   ON reserves_in
   (exchange_account_section,
   reserve_in_serial_id DESC
@@ -116,7 +116,7 @@ CREATE TABLE IF NOT EXISTS reserves_close
   ,amount_frac INT4 NOT NULL
   ,closing_fee_val INT8 NOT NULL
   ,closing_fee_frac INT4 NOT NULL);
-CREATE INDEX reserves_close_by_reserve
+CREATE INDEX IF NOT EXISTS reserves_close_by_reserve
   ON reserves_close
   (reserve_pub);
 -- Table with the withdraw operations that have been performed on a reserve.
@@ -137,13 +137,13 @@ CREATE TABLE IF NOT EXISTS reserves_out
   ,amount_with_fee_frac INT4 NOT NULL
   );
 -- Index blindcoins(reserve_pub) for get_reserves_out statement
-CREATE INDEX reserves_out_reserve_pub_index
+CREATE INDEX IF NOT EXISTS reserves_out_reserve_pub_index
   ON reserves_out
   (reserve_pub);
-CREATE INDEX reserves_out_execution_date
+CREATE INDEX IF NOT EXISTS reserves_out_execution_date
   ON reserves_out
   (execution_date);
-CREATE INDEX reserves_out_for_get_withdraw_info
+CREATE INDEX IF NOT EXISTS reserves_out_for_get_withdraw_info
   ON reserves_out
   (denom_pub_hash
   ,h_blind_ev
@@ -155,7 +155,7 @@ CREATE TABLE IF NOT EXISTS known_coins
   ,denom_pub_hash BYTEA NOT NULL REFERENCES denominations (denom_pub_hash) ON DELETE CASCADE
   ,denom_sig BYTEA NOT NULL
   );
-CREATE INDEX known_coins_by_denomination
+CREATE INDEX IF NOT EXISTS known_coins_by_denomination
   ON known_coins
   (denom_pub_hash);
 -- Table with the commitments made when melting a coin. */
@@ -168,7 +168,7 @@ CREATE TABLE IF NOT EXISTS refresh_commitments
   ,amount_with_fee_frac INT4 NOT NULL
   ,noreveal_index INT4 NOT NULL
   );
-CREATE INDEX refresh_commitments_old_coin_pub_index
+CREATE INDEX IF NOT EXISTS refresh_commitments_old_coin_pub_index
   ON refresh_commitments
   (old_coin_pub);
 -- Table with the revelations about the new coins that are to be created
@@ -188,7 +188,7 @@ CREATE TABLE IF NOT EXISTS refresh_revealed_coins
   ,PRIMARY KEY (rc, newcoin_index)
   ,UNIQUE (h_coin_ev)
   );
-CREATE INDEX refresh_revealed_coins_coin_pub_index
+CREATE INDEX IF NOT EXISTS refresh_revealed_coins_coin_pub_index
   ON refresh_revealed_coins
   (denom_pub_hash);
 -- Table with the transfer keys of a refresh operation; includes
@@ -203,7 +203,7 @@ CREATE TABLE IF NOT EXISTS refresh_transfer_keys
 -- for get_link (not sure if this helps, as there should be very few
 -- transfer_pubs per rc, but at least in theory this helps the ORDER BY
 -- clause.
-CREATE INDEX refresh_transfer_keys_coin_tpub
+CREATE INDEX IF NOT EXISTS refresh_transfer_keys_coin_tpub
   ON refresh_transfer_keys
   (rc
   ,transfer_pub
@@ -228,14 +228,14 @@ CREATE TABLE IF NOT EXISTS deposits
   ,UNIQUE (coin_pub, merchant_pub, h_contract_terms)
   );
 -- Index for get_deposit_for_wtid and get_deposit_statement */
-CREATE INDEX deposits_coin_pub_merchant_contract_index
+CREATE INDEX IF NOT EXISTS deposits_coin_pub_merchant_contract_index
   ON deposits
   (coin_pub
   ,merchant_pub
   ,h_contract_terms
   );
 -- Index for deposits_get_ready
-CREATE INDEX deposits_get_ready_index
+CREATE INDEX IF NOT EXISTS deposits_get_ready_index
   ON deposits
   (tiny
   ,done
@@ -243,7 +243,7 @@ CREATE INDEX deposits_get_ready_index
   ,refund_deadline
   );
 -- Index for deposits_iterate_matching
-CREATE INDEX deposits_iterate_matching
+CREATE INDEX IF NOT EXISTS deposits_iterate_matching
   ON deposits
   (merchant_pub
   ,h_wire
@@ -265,7 +265,7 @@ CREATE TABLE IF NOT EXISTS refunds
   ,amount_with_fee_frac INT4 NOT NULL
   ,PRIMARY KEY (coin_pub, merchant_pub, h_contract_terms, rtransaction_id)
   );
-CREATE INDEX refunds_coin_pub_index
+CREATE INDEX IF NOT EXISTS refunds_coin_pub_index
   ON refunds
   (coin_pub);
 -- This table contains the data for
@@ -287,7 +287,7 @@ CREATE TABLE IF NOT EXISTS aggregation_tracking
   ,wtid_raw BYTEA  CONSTRAINT wire_out_ref REFERENCES wire_out(wtid_raw) ON DELETE CASCADE DEFERRABLE
   );
 -- Index for lookup_transactions statement on wtid
-CREATE INDEX aggregation_tracking_wtid_index
+CREATE INDEX IF NOT EXISTS aggregation_tracking_wtid_index
   ON aggregation_tracking
   (wtid_raw);
 -- Table for the wire fees.
@@ -302,7 +302,7 @@ CREATE TABLE IF NOT EXISTS wire_fee
   ,master_sig BYTEA NOT NULL CHECK (LENGTH(master_sig)=64)
   ,PRIMARY KEY (wire_method, start_date)
   );
-CREATE INDEX wire_fee_gc_index
+CREATE INDEX IF NOT EXISTS wire_fee_gc_index
   ON wire_fee
   (end_date);
 -- Table for /recoup information
@@ -317,13 +317,13 @@ CREATE TABLE IF NOT EXISTS recoup
   ,timestamp INT8 NOT NULL
   ,h_blind_ev BYTEA NOT NULL REFERENCES reserves_out (h_blind_ev) ON DELETE CASCADE
   );
-CREATE INDEX recoup_by_coin_index
+CREATE INDEX IF NOT EXISTS recoup_by_coin_index
   ON recoup
   (coin_pub);
-CREATE INDEX recoup_by_h_blind_ev
+CREATE INDEX IF NOT EXISTS recoup_by_h_blind_ev
   ON recoup
   (h_blind_ev);
-CREATE INDEX recoup_for_by_reserve
+CREATE INDEX IF NOT EXISTS recoup_for_by_reserve
   ON recoup
   (coin_pub
   ,h_blind_ev
@@ -340,13 +340,13 @@ CREATE TABLE IF NOT EXISTS recoup_refresh
   ,timestamp INT8 NOT NULL
   ,h_blind_ev BYTEA NOT NULL REFERENCES refresh_revealed_coins (h_coin_ev) ON DELETE CASCADE
   );
-CREATE INDEX recoup_refresh_by_coin_index
+CREATE INDEX IF NOT EXISTS recoup_refresh_by_coin_index
   ON recoup_refresh
   (coin_pub);
-CREATE INDEX recoup_refresh_by_h_blind_ev
+CREATE INDEX IF NOT EXISTS recoup_refresh_by_h_blind_ev
   ON recoup_refresh
   (h_blind_ev);
-CREATE INDEX recoup_refresh_for_by_reserve
+CREATE INDEX IF NOT EXISTS recoup_refresh_for_by_reserve
   ON recoup_refresh
   (coin_pub
   ,h_blind_ev
@@ -360,7 +360,7 @@ CREATE TABLE IF NOT EXISTS prewire
   ,buf BYTEA NOT NULL
   );
 -- Index for wire_prepare_data_get and gc_prewire statement
-CREATE INDEX prepare_iteration_index
+CREATE INDEX IF NOT EXISTS prepare_iteration_index
   ON prewire
   (finished);
 
diff --git a/src/exchangedb/exchangedb_plugin.c b/src/exchangedb/exchangedb_plugin.c
index 8e61f860b..f4c2eea99 100644
--- a/src/exchangedb/exchangedb_plugin.c
+++ b/src/exchangedb/exchangedb_plugin.c
@@ -35,7 +35,6 @@ TALER_EXCHANGEDB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
   char *plugin_name;
   char *lib_name;
-  struct GNUNET_CONFIGURATION_Handle *cfg_dup;
   struct TALER_EXCHANGEDB_Plugin *plugin;
 
   if (GNUNET_SYSERR ==
@@ -53,13 +52,12 @@ TALER_EXCHANGEDB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
                           "libtaler_plugin_exchangedb_%s",
                           plugin_name);
   GNUNET_free (plugin_name);
-  cfg_dup = GNUNET_CONFIGURATION_dup (cfg);
-  plugin = GNUNET_PLUGIN_load (lib_name, cfg_dup);
+  plugin = GNUNET_PLUGIN_load (lib_name,
+                               (void *) cfg);
   if (NULL != plugin)
     plugin->library_name = lib_name;
   else
     GNUNET_free (lib_name);
-  GNUNET_CONFIGURATION_destroy (cfg_dup);
   return plugin;
 }
 
diff --git a/src/exchangedb/plugin_exchangedb_postgres.c b/src/exchangedb/plugin_exchangedb_postgres.c
index 4d0b1bb6a..9df2fe770 100644
--- a/src/exchangedb/plugin_exchangedb_postgres.c
+++ b/src/exchangedb/plugin_exchangedb_postgres.c
@@ -109,10 +109,9 @@ struct PostgresClosure
   pthread_key_t db_conn_threadlocal;
 
   /**
-   * Database connection string, as read from
-   * the configuration.
+   * Our configuration.
    */
-  char *connection_cfg_str;
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
 
   /**
    * Directory with SQL statements to run to create tables.
@@ -158,16 +157,12 @@ postgres_drop_tables (void *cls)
 {
   struct PostgresClosure *pc = cls;
   struct GNUNET_PQ_Context *conn;
-  char *drop_dir;
-
-  GNUNET_asprintf (&drop_dir,
-                   "%sdrop",
-                   pc->sql_dir);
-  conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                            drop_dir,
-                            NULL,
-                            NULL);
-  GNUNET_free (drop_dir);
+
+  conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                     "exchangedb-postgres",
+                                     "drop",
+                                     NULL,
+                                     NULL);
   if (NULL == conn)
     return GNUNET_SYSERR;
   GNUNET_PQ_disconnect (conn);
@@ -187,10 +182,11 @@ postgres_create_tables (void *cls)
   struct PostgresClosure *pc = cls;
   struct GNUNET_PQ_Context *conn;
 
-  conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                            pc->sql_dir,
-                            NULL,
-                            NULL);
+  conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                     "exchangedb-postgres",
+                                     "exchange-",
+                                     NULL,
+                                     NULL);
   if (NULL == conn)
     return GNUNET_SYSERR;
   GNUNET_PQ_disconnect (conn);
@@ -1387,10 +1383,11 @@ postgres_get_session (void *cls)
       GNUNET_PQ_PREPARED_STATEMENT_END
     };
 
-    db_conn = GNUNET_PQ_connect (pc->connection_cfg_str,
-                                 NULL,
-                                 es,
-                                 ps);
+    db_conn = GNUNET_PQ_connect_with_cfg (pc->cfg,
+                                          "exchangedb-postgres",
+                                          NULL,
+                                          es,
+                                          ps);
   }
   if (NULL == db_conn)
     return NULL;
@@ -5371,10 +5368,11 @@ postgres_gc (void *cls)
       GNUNET_PQ_PREPARED_STATEMENT_END
     };
 
-    conn = GNUNET_PQ_connect (pg->connection_cfg_str,
-                              NULL,
-                              NULL,
-                              ps);
+    conn = GNUNET_PQ_connect_with_cfg (pg->cfg,
+                                       "exchangedb-postgres",
+                                       NULL,
+                                       NULL,
+                                       ps);
   }
   if (NULL == conn)
     return GNUNET_SYSERR;
@@ -7212,12 +7210,12 @@ postgres_select_deposits_missing_wire (void *cls,
 void *
 libtaler_plugin_exchangedb_postgres_init (void *cls)
 {
-  struct GNUNET_CONFIGURATION_Handle *cfg = cls;
+  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
   struct PostgresClosure *pg;
   struct TALER_EXCHANGEDB_Plugin *plugin;
-  const char *ec;
 
   pg = GNUNET_new (struct PostgresClosure);
+  pg->cfg = cfg;
   pg->main_self = pthread_self (); /* loaded while single-threaded! */
   if (GNUNET_OK !=
       GNUNET_CONFIGURATION_get_value_filename (cfg,
@@ -7239,28 +7237,6 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
     GNUNET_free (pg);
     return NULL;
   }
-  ec = getenv ("TALER_EXCHANGEDB_POSTGRES_CONFIG");
-  if (NULL != ec)
-  {
-    pg->connection_cfg_str = GNUNET_strdup (ec);
-  }
-  else
-  {
-    if (GNUNET_OK !=
-        GNUNET_CONFIGURATION_get_value_string (cfg,
-                                               "exchangedb-postgres",
-                                               "CONFIG",
-                                               &pg->connection_cfg_str))
-    {
-      GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
-                                 "exchangedb-postgres",
-                                 "CONFIG");
-      GNUNET_free (pg->sql_dir);
-      GNUNET_free (pg);
-      return NULL;
-    }
-  }
-
   if ( (GNUNET_OK !=
         GNUNET_CONFIGURATION_get_value_time (cfg,
                                              "exchangedb",
@@ -7276,7 +7252,6 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
     GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
                                "exchangedb",
                                "LEGAL/IDLE_RESERVE_EXPIRATION_TIME");
-    GNUNET_free (pg->connection_cfg_str);
     GNUNET_free (pg->sql_dir);
     GNUNET_free (pg);
     return NULL;
@@ -7290,7 +7265,6 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
     GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
                                "taler",
                                "CURRENCY");
-    GNUNET_free (pg->connection_cfg_str);
     GNUNET_free (pg->sql_dir);
     GNUNET_free (pg);
     return NULL;
@@ -7406,7 +7380,6 @@ libtaler_plugin_exchangedb_postgres_done (void *cls)
   /* If we launched a session for the main thread,
      kill it here before we unload */
   db_conn_destroy (pg->main_session);
-  GNUNET_free (pg->connection_cfg_str);
   GNUNET_free (pg->sql_dir);
   GNUNET_free (pg->currency);
   GNUNET_free (pg);
diff --git a/src/include/taler_bank_service.h b/src/include/taler_bank_service.h
index 98a1017c2..c9c93fac5 100644
--- a/src/include/taler_bank_service.h
+++ b/src/include/taler_bank_service.h
@@ -89,6 +89,73 @@ struct TALER_BANK_AuthenticationData
 
 };
 
+/* ********************* /config *********************** */
+
+/**
+ * @brief A /config Handle
+ */
+struct TALER_BANK_ConfigHandle;
+
+/**
+ * Configuration data provided by the bank.
+ */
+struct TALER_BANK_Configuration
+{
+  /**
+   * Current protocol version. Libtool style.
+   */
+  const char *version;
+
+  /**
+   * Currency used by the bank.
+   */
+  const char *currency;
+};
+
+
+/**
+ * Function called with configuration details from the bank.
+ *
+ * @param cls closure
+ * @param http status code
+ * @param ec taler error code
+ * @param config the configuration, NULL on error
+ */
+typedef void
+(*TALER_BANK_ConfigCallback)(void *cls,
+                             unsigned int http_status,
+                             enum TALER_ErrorCode ec,
+                             const struct TALER_BANK_Configuration *config);
+
+/**
+ * Request the configuration of the bank.
+ *
+ * @param ctx curl context for the event loop
+ * @param auth authentication data to use
+ * @param hres_cb the callback to call with the
+ *        configuration
+ * @param hres_cb_cls closure for the above callback
+ * @return NULL if the inputs are invalid (i.e. zero value for
+ *         @e num_results). In this case, the callback is not
+ *         called.
+ */
+struct TALER_BANK_ConfigHandle *
+TALER_BANK_configuration (struct GNUNET_CURL_Context *ctx,
+                          const struct TALER_BANK_AuthenticationData *auth,
+                          TALER_BANK_ConfigCallback hres_cb,
+                          void *hres_cb_cls);
+
+
+/**
+ * Cancel a configuration request.  This function cannot be
+ * used on a request handle if a response is already
+ * served for it.
+ *
+ * @param ch the configuration request handle
+ */
+void
+TALER_BANK_configuration_cancel (struct TALER_BANK_ConfigHandle *ch);
+
 
 /* ********************* /admin/add/incoming *********************** */
 
@@ -160,7 +227,7 @@ TALER_BANK_admin_add_incoming_cancel (struct
                                       TALER_BANK_AdminAddIncomingHandle *aai);
 
 
-/* ********************* /taler/transfer *********************** */
+/* ********************* /transfer *********************** */
 
 /**
  * Prepare for exeuction of a wire transfer.
@@ -243,7 +310,7 @@ TALER_BANK_execute_wire_transfer_cancel (struct
                                          TALER_BANK_WireExecuteHandle *weh);
 
 
-/* ********************* /taler/credits *********************** */
+/* ********************* /history/incoming *********************** */
 
 /**
  * Handle for querying the bank for transactions
@@ -347,7 +414,7 @@ void
 TALER_BANK_credit_history_cancel (struct TALER_BANK_CreditHistoryHandle *hh);
 
 
-/* ********************* /taler/debits *********************** */
+/* ********************* /history/outgoing *********************** */
 
 /**
  * Handle for querying the bank for transactions
diff --git a/src/include/taler_error_codes.h b/src/include/taler_error_codes.h
index ac7f92888..917ac36db 100644
--- a/src/include/taler_error_codes.h
+++ b/src/include/taler_error_codes.h
@@ -81,6 +81,11 @@ enum TALER_ErrorCode
   TALER_EC_JSON_ALLOCATION_FAILURE = 7,
 
   /**
+   * HTTP method invalid for this URL.
+   */
+  TALER_EC_METHOD_INVALID = 8,
+
+  /**
    * The exchange failed to even just initialize its connection to the
    * database.  This response is provided with HTTP status code
    * MHD_HTTP_INTERNAL_SERVER_ERROR.
diff --git a/src/include/taler_fakebank_lib.h b/src/include/taler_fakebank_lib.h
index 9324bdce1..8601a8d8d 100644
--- a/src/include/taler_fakebank_lib.h
+++ b/src/include/taler_fakebank_lib.h
@@ -44,10 +44,12 @@ struct TALER_FAKEBANK_Handle;
  * would have issued the correct wire transfer orders.
  *
  * @param port port to listen to
+ * @param currency which currency should the bank offer
  * @return NULL on error
  */
 struct TALER_FAKEBANK_Handle *
-TALER_FAKEBANK_start (uint16_t port);
+TALER_FAKEBANK_start (uint16_t port,
+                      const char *currency);
 
 
 /**
diff --git a/src/include/taler_testing_lib.h b/src/include/taler_testing_lib.h
index 0b3d19999..5aa50155c 100644
--- a/src/include/taler_testing_lib.h
+++ b/src/include/taler_testing_lib.h
@@ -635,7 +635,7 @@ typedef void
  * @param main_cb the "run" method which coontains all the
  *        commands.
  * @param main_cb_cls a closure for "run", typically NULL.
- * @param config_filename configuration filename.
+ * @param cfg configuration to use
  * @param exchanged exchange process handle: will be put in the
  *        state as some commands - e.g. revoke - need to send
  *        signal to it, for example to let it know to reload the
@@ -650,7 +650,7 @@ typedef void
 int
 TALER_TESTING_setup (TALER_TESTING_Main main_cb,
                      void *main_cb_cls,
-                     const char *config_filename,
+                     const struct GNUNET_CONFIGURATION_Handle *cfg,
                      struct GNUNET_OS_Process *exchanged,
                      int exchange_connect);
 
@@ -789,11 +789,13 @@ TALER_TESTING_run_bank (const char *config_filename,
  * from the base URL.
  *
  * @param bank_url bank's base URL.
+ * @param currency currency the bank uses
  * @return the fakebank process handle, or NULL if any
  *         error occurs.
  */
 struct TALER_FAKEBANK_Handle *
-TALER_TESTING_run_fakebank (const char *bank_url);
+TALER_TESTING_run_fakebank (const char *bank_url,
+                            const char *currency);
 
 
 /**
diff --git a/src/json/json.c b/src/json/json.c
index 6de299319..f0c0aff57 100644
--- a/src/json/json.c
+++ b/src/json/json.c
@@ -81,7 +81,8 @@ TALER_JSON_get_error_code (const json_t *json)
      so we are dealing with a missing error code here.  */
   if (NULL == jc)
   {
-    GNUNET_break_op (0);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Expected Taler error code `code' in JSON, but field does not exist!\n");
     return TALER_EC_INVALID;
   }
   if (json_is_integer (jc))
diff --git a/src/testing/test_bank_api.c b/src/testing/test_bank_api.c
index bdafdc5fd..75e22b59e 100644
--- a/src/testing/test_bank_api.c
+++ b/src/testing/test_bank_api.c
@@ -52,6 +52,7 @@ static struct GNUNET_OS_Process *bankd;
  */
 static int with_fakebank;
 
+
 /**
  * Main function that will tell the interpreter what commands to
  * run.
@@ -116,12 +117,32 @@ run (void *cls,
 }
 
 
+/**
+ * Runs #TALER_TESTING_setup() using the configuration.
+ *
+ * @param cls unused
+ * @param cfg configuration to use
+ * @return status code
+ */
+static int
+setup_with_cfg (void *cls,
+                const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  (void) cls;
+  return TALER_TESTING_setup (&run,
+                              NULL,
+                              cfg,
+                              NULL,
+                              GNUNET_NO);
+}
+
+
 int
 main (int argc,
       char *const *argv)
 {
-  int rv;
   const char *cfgfilename;
+  int rv;
 
   /* These environment variables get in the way... */
   unsetenv ("XDG_DATA_HOME");
@@ -165,12 +186,13 @@ main (int argc,
       return 77;
     }
   }
-
-  rv = (GNUNET_OK == TALER_TESTING_setup (&run,
-                                          NULL,
-                                          cfgfilename,
-                                          NULL,
-                                          GNUNET_NO)) ? 0 : 1;
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_parse_and_run (cfgfilename,
+                                          &setup_with_cfg,
+                                          NULL))
+    rv = 1;
+  else
+    rv = 0;
   if (GNUNET_NO == with_fakebank)
   {
 
diff --git a/src/testing/test_taler_exchange_aggregator.c b/src/testing/test_taler_exchange_aggregator.c
index c709e5fe9..2e8a35ce2 100644
--- a/src/testing/test_taler_exchange_aggregator.c
+++ b/src/testing/test_taler_exchange_aggregator.c
@@ -57,36 +57,6 @@ static char *config_filename;
 
 #define USER42_ACCOUNT "42"
 
-/**
- * @return GNUNET_NO if database could not be prepared,
- * otherwise GNUNET_OK
- */
-static int
-prepare_database (void *cls,
-                  const struct GNUNET_CONFIGURATION_Handle *cfg)
-{
-  dbc.plugin = TALER_EXCHANGEDB_plugin_load (cfg);
-  if (NULL == dbc.plugin)
-  {
-    GNUNET_break (0);
-    result = 77;
-    return GNUNET_NO;
-  }
-  if (GNUNET_OK !=
-      dbc.plugin->create_tables (dbc.plugin->cls))
-  {
-    GNUNET_break (0);
-    TALER_EXCHANGEDB_plugin_unload (dbc.plugin);
-    dbc.plugin = NULL;
-    result = 77;
-    return GNUNET_NO;
-  }
-  dbc.session = dbc.plugin->get_session (dbc.plugin->cls);
-  GNUNET_assert (NULL != dbc.session);
-
-  return GNUNET_OK;
-}
-
 
 /**
  * Collects all the tests.
@@ -454,6 +424,48 @@ run (void *cls,
 }
 
 
+/**
+ * Prepare database an launch the test.
+ *
+ * @param cls unused
+ * @param cfg our configuration
+ * @return #GNUNET_NO if database could not be prepared,
+ * otherwise #GNUNET_OK
+ */
+static int
+prepare_database (void *cls,
+                  const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  dbc.plugin = TALER_EXCHANGEDB_plugin_load (cfg);
+  if (NULL == dbc.plugin)
+  {
+    GNUNET_break (0);
+    result = 77;
+    return GNUNET_NO;
+  }
+  if (GNUNET_OK !=
+      dbc.plugin->create_tables (dbc.plugin->cls))
+  {
+    GNUNET_break (0);
+    TALER_EXCHANGEDB_plugin_unload (dbc.plugin);
+    dbc.plugin = NULL;
+    result = 77;
+    return GNUNET_NO;
+  }
+  dbc.session = dbc.plugin->get_session (dbc.plugin->cls);
+  GNUNET_assert (NULL != dbc.session);
+
+  result = TALER_TESTING_setup (&run,
+                                NULL,
+                                cfg,
+                                NULL, // no exchange process handle.
+                                GNUNET_NO); // do not try to connect to the exchange
+
+
+  return GNUNET_OK;
+}
+
+
 int
 main (int argc,
       char *const argv[])
@@ -507,12 +519,6 @@ main (int argc,
     return result;
   }
 
-  result = TALER_TESTING_setup (&run,
-                                NULL,
-                                config_filename,
-                                NULL, // no exchange process handle.
-                                GNUNET_NO); // do not try to connect to the exchange
-
   GNUNET_free (config_filename);
   GNUNET_free (testname);
   dbc.plugin->drop_tables (dbc.plugin->cls);
diff --git a/src/testing/testing_api_cmd_exec_wirewatch.c b/src/testing/testing_api_cmd_exec_wirewatch.c
index 44de96838..7a1a27a51 100644
--- a/src/testing/testing_api_cmd_exec_wirewatch.c
+++ b/src/testing/testing_api_cmd_exec_wirewatch.c
@@ -67,7 +67,7 @@ wirewatch_run (void *cls,
                                "taler-exchange-wirewatch",
                                "taler-exchange-wirewatch",
                                "-c", ws->config_filename,
-                               "-T", /* exit when done */
+                               "-t", /* exit when done */
                                NULL);
   if (NULL == ws->wirewatch_proc)
   {
diff --git a/src/testing/testing_api_helpers_bank.c b/src/testing/testing_api_helpers_bank.c
index 7b8b203a3..35ef4792f 100644
--- a/src/testing/testing_api_helpers_bank.c
+++ b/src/testing/testing_api_helpers_bank.c
@@ -36,11 +36,13 @@
  * from the base URL.
  *
  * @param bank_url bank's base URL.
+ * @param currency currency the bank uses
  * @return the fakebank process handle, or NULL if any
  *         error occurs.
  */
 struct TALER_FAKEBANK_Handle *
-TALER_TESTING_run_fakebank (const char *bank_url)
+TALER_TESTING_run_fakebank (const char *bank_url,
+                            const char *currency)
 {
   const char *port;
   long pnum;
@@ -56,7 +58,8 @@ TALER_TESTING_run_fakebank (const char *bank_url)
               "Starting Fakebank on port %u (%s)\n",
               (unsigned int) pnum,
               bank_url);
-  fakebankd = TALER_FAKEBANK_start ((uint16_t) pnum);
+  fakebankd = TALER_FAKEBANK_start ((uint16_t) pnum,
+                                    currency);
   if (NULL == fakebankd)
   {
     GNUNET_break (0);
diff --git a/src/testing/testing_api_helpers_exchange.c b/src/testing/testing_api_helpers_exchange.c
index 29c96db19..911bc6f0e 100644
--- a/src/testing/testing_api_helpers_exchange.c
+++ b/src/testing/testing_api_helpers_exchange.c
@@ -788,7 +788,7 @@ TALER_TESTING_setup_with_exchange_cfg (void *cls,
   /* NOTE: this call blocks.  */
   result = TALER_TESTING_setup (setup_ctx->main_cb,
                                 setup_ctx->main_cb_cls,
-                                setup_ctx->config_filename,
+                                cfg,
                                 exchanged,
                                 GNUNET_YES);
   GNUNET_break (0 ==
diff --git a/src/testing/testing_api_loop.c b/src/testing/testing_api_loop.c
index 61b95c2e1..e9ccdb81c 100644
--- a/src/testing/testing_api_loop.c
+++ b/src/testing/testing_api_loop.c
@@ -124,7 +124,33 @@ TALER_TESTING_run_with_fakebank (struct TALER_TESTING_Interpreter *is,
                                  struct TALER_TESTING_Command *commands,
                                  const char *bank_url)
 {
-  is->fakebank = TALER_TESTING_run_fakebank (bank_url);
+  char *currency;
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (is->cfg,
+                                             "taler",
+                                             "CURRENCY",
+                                             &currency))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "taler",
+                               "CURRENCY");
+    is->result = GNUNET_SYSERR;
+    return;
+  }
+  if (strlen (currency) >= TALER_CURRENCY_LEN)
+  {
+    GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
+                               "taler",
+                               "CURRENCY",
+                               "Value is too long");
+    GNUNET_free (currency);
+    is->result = GNUNET_SYSERR;
+    return;
+  }
+  is->fakebank = TALER_TESTING_run_fakebank (bank_url,
+                                             currency);
+  GNUNET_free (currency);
   if (NULL == is->fakebank)
   {
     GNUNET_break (0);
@@ -530,14 +556,6 @@ struct MainContext
   struct TALER_TESTING_Interpreter *is;
 
   /**
-   * Configuration filename.  The wrapper uses it to fetch
-   * the exchange port number; We could have passed the port
-   * number here, but having the config filename seems more
-   * generic.
-   */
-  const char *config_filename;
-
-  /**
    * URL of the exchange.
    */
   char *exchange_url;
@@ -683,18 +701,16 @@ do_abort (void *cls)
  * and responsible to run the "run" method.
  *
  * @param cls a `struct MainContext *`
- * @param cfg configuration to use
  */
-static int
-main_exchange_connect_with_cfg (void *cls,
-                                const struct GNUNET_CONFIGURATION_Handle *cfg)
+static void
+main_wrapper_exchange_connect (void *cls)
 {
   struct MainContext *main_ctx = cls;
   struct TALER_TESTING_Interpreter *is = main_ctx->is;
   char *exchange_url;
 
   if (GNUNET_OK !=
-      GNUNET_CONFIGURATION_get_value_string (cfg,
+      GNUNET_CONFIGURATION_get_value_string (is->cfg,
                                              "exchange",
                                              "BASE_URL",
                                              &exchange_url))
@@ -702,40 +718,18 @@ main_exchange_connect_with_cfg (void *cls,
     GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
                                "exchange",
                                "BASE_URL");
-    return GNUNET_SYSERR;
+    return;
   }
   main_ctx->exchange_url = exchange_url;
-  is->cfg = cfg;
   is->timeout_task = GNUNET_SCHEDULER_add_shutdown (&do_abort,
                                                     main_ctx);
   GNUNET_break
-    (NULL != (is->exchange = TALER_EXCHANGE_connect
-                               (is->ctx,
-                               exchange_url,
-                               &TALER_TESTING_cert_cb,
-                               main_ctx,
-                               TALER_EXCHANGE_OPTION_END)));
-  is->cfg = NULL;
-  return GNUNET_OK;
-}
-
-
-/**
- * Initialize scheduler loop and curl context for the testcase,
- * and responsible to run the "run" method.
- *
- * @param cls a `struct MainContext *`
- */
-static void
-main_wrapper_exchange_connect (void *cls)
-{
-  struct MainContext *main_ctx = cls;
-
-  GNUNET_break (GNUNET_OK ==
-                GNUNET_CONFIGURATION_parse_and_run (main_ctx->config_filename,
-                                                    &
-                                                    main_exchange_connect_with_cfg,
-                                                    main_ctx));
+    (NULL != (is->exchange =
+                TALER_EXCHANGE_connect (is->ctx,
+                                        exchange_url,
+                                        &TALER_TESTING_cert_cb,
+                                        main_ctx,
+                                        TALER_EXCHANGE_OPTION_END)));
 }
 
 
@@ -746,7 +740,7 @@ main_wrapper_exchange_connect (void *cls)
  * @param main_cb the "run" method which contains all the
  *        commands.
  * @param main_cb_cls a closure for "run", typically NULL.
- * @param config_filename configuration filename.
+ * @param cfg configuration to use
  * @param exchanged exchange process handle: will be put in the
  *        state as some commands - e.g. revoke - need to send
  *        signal to it, for example to let it know to reload the
@@ -761,7 +755,7 @@ main_wrapper_exchange_connect (void *cls)
 int
 TALER_TESTING_setup (TALER_TESTING_Main main_cb,
                      void *main_cb_cls,
-                     const char *config_filename,
+                     const struct GNUNET_CONFIGURATION_Handle *cfg,
                      struct GNUNET_OS_Process *exchanged,
                      int exchange_connect)
 {
@@ -771,9 +765,6 @@ TALER_TESTING_setup (TALER_TESTING_Main main_cb,
     .main_cb_cls = main_cb_cls,
     /* needed to init the curl ctx */
     .is = &is,
-    /* needed to read values like exchange port
-     * number to construct the exchange url.*/
-    .config_filename = config_filename
   };
   struct GNUNET_SIGNAL_Context *shc_chld;
 
@@ -781,6 +772,7 @@ TALER_TESTING_setup (TALER_TESTING_Main main_cb,
           0,
           sizeof (is));
   is.exchanged = exchanged;
+  is.cfg = cfg;
   sigpipe = GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO,
                               GNUNET_NO, GNUNET_NO);
   GNUNET_assert (NULL != sigpipe);