fix cyclic dependency by combining exchange-lib and auditor-lib directories

1 files changed, 1050 insertions, 0 deletions

diff --git a/src/lib/testing_api_helpers.c b/src/lib/testing_api_helpers.c
new file mode 100644
index 000000000..e56a57b92
--- /dev/null
+++ b/src/lib/testing_api_helpers.c
@@ -0,0 +1,1050 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2018 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 exchange-lib/testing_api_helpers.c
+ * @brief helper functions
+ * @author Christian Grothoff
+ * @author Marcello Stanisci
+ */
+#include "platform.h"
+#include "taler_json_lib.h"
+#include <gnunet/gnunet_curl_lib.h>
+#include "exchange_api_handle.h"
+#include "taler_signatures.h"
+#include "taler_testing_lib.h"
+
+
+/**
+ * Remove files from previous runs
+ *
+ * @param config_name configuration filename.
+ */
+void
+TALER_TESTING_cleanup_files (const char *config_name)
+{
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_parse_and_run (config_name,
+					  &TALER_TESTING_cleanup_files_cfg,
+					  NULL))
+    exit (77);
+}
+
+
+/**
+ * Remove files from previous runs
+ *
+ * @param cls NULL
+ * @param cfg configuration
+ * @return #GNUNET_OK on success
+ */
+int
+TALER_TESTING_cleanup_files_cfg (void *cls,
+				 const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  char *dir;
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_filename (cfg,
+					       "exchange",
+					       "keydir",
+					       &dir))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+			       "exchange",
+			       "keydir");
+    return GNUNET_SYSERR;
+  }
+  if (GNUNET_YES ==
+      GNUNET_DISK_directory_test (dir,
+                                  GNUNET_NO))
+    GNUNET_break (GNUNET_OK ==
+                  GNUNET_DISK_directory_remove (dir));
+  GNUNET_free (dir);
+  // TODO: auditor-specific clean-up here!
+  return GNUNET_OK;
+}
+
+
+/**
+ * Run `taler-exchange-keyup`.
+ *
+ * @param config_filename configuration file to use
+ * @param output_filename where to write the output for the auditor
+ * @return #GNUNET_OK on success
+ */
+int
+TALER_TESTING_run_keyup (const char *config_filename,
+			 const char *output_filename)
+{
+  struct GNUNET_OS_Process *proc;
+
+  proc = GNUNET_OS_start_process (GNUNET_NO,
+                                  GNUNET_OS_INHERIT_STD_ALL,
+                                  NULL, NULL, NULL,
+                                  "taler-exchange-keyup",
+                                  "taler-exchange-keyup",
+                                  "-c", config_filename,
+                                  "-o", output_filename,
+                                  NULL);
+  if (NULL == proc)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to run `taler-exchange-keyup`,"
+                " is your PATH correct?\n");
+    return GNUNET_SYSERR;
+  }
+  GNUNET_OS_process_wait (proc);
+  GNUNET_OS_process_destroy (proc);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Run `taler-auditor-sign`.
+ *
+ * @param config_filename configuration file to use
+ * @param exchange_master_pub master public key of the exchange
+ * @param auditor_base_url what is the base URL of the auditor
+ * @param signdata_in where is the information from taler-exchange-keyup
+ * @param signdata_out where to write the output for the exchange
+ * @return #GNUNET_OK on success
+ */
+int
+TALER_TESTING_run_auditor_sign (const char *config_filename,
+				const char *exchange_master_pub,
+				const char *auditor_base_url,
+				const char *signdata_in,
+				const char *signdata_out)
+{
+  struct GNUNET_OS_Process *proc;
+
+  proc = GNUNET_OS_start_process (GNUNET_NO,
+                                  GNUNET_OS_INHERIT_STD_ALL,
+                                  NULL, NULL, NULL,
+                                  "taler-auditor-sign",
+                                  "taler-auditor-sign",
+                                  "-c", config_filename,
+                                  "-u", auditor_base_url,
+                                  "-m", exchange_master_pub,
+                                  "-r", signdata_in,
+                                  "-o", signdata_out,
+                                  NULL);
+  if (NULL == proc)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to run `taler-auditor-sign`,"
+                " is your PATH correct?\n");
+    return GNUNET_SYSERR;
+  }
+  GNUNET_OS_process_wait (proc);
+  GNUNET_OS_process_destroy (proc);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Run `taler-auditor-exchange`.
+ *
+ * @param config_filename configuration file to use
+ * @param exchange_master_pub master public key of the exchange
+ * @param exchange_base_url what is the base URL of the exchange
+ * @param do_remove #GNUNET_NO to add exchange, #GNUNET_YES to remove
+ * @return #GNUNET_OK on success
+ */
+int
+TALER_TESTING_run_auditor_exchange (const char *config_filename,
+                                    const char *exchange_master_pub,
+                                    const char *exchange_base_url,
+                                    int do_remove)
+{
+  struct GNUNET_OS_Process *proc;
+
+  proc = GNUNET_OS_start_process (GNUNET_NO,
+                                  GNUNET_OS_INHERIT_STD_ALL,
+                                  NULL, NULL, NULL,
+                                  "taler-auditor-exchange",
+                                  "taler-auditor-exchange",
+                                  "-c", config_filename,
+                                  "-u", exchange_base_url,
+                                  "-m", exchange_master_pub,
+                                  (GNUNET_YES == do_remove)
+                                  ? "-r"
+                                  : NULL,
+                                  NULL);
+  if (NULL == proc)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to run `taler-auditor-exchange`,"
+                " is your PATH correct?\n");
+    return GNUNET_SYSERR;
+  }
+  GNUNET_OS_process_wait (proc);
+  GNUNET_OS_process_destroy (proc);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Run `taler-exchange-dbinit -r` (reset exchange database).
+ *
+ * @param config_filename configuration file to use
+ * @return #GNUNET_OK on success
+ */
+int
+TALER_TESTING_exchange_db_reset (const char *config_filename)
+{
+  struct GNUNET_OS_Process *proc;
+  enum GNUNET_OS_ProcessStatusType type;
+  unsigned long code;
+
+  proc = GNUNET_OS_start_process (GNUNET_NO,
+                                  GNUNET_OS_INHERIT_STD_ALL,
+                                  NULL, NULL, NULL,
+                                  "taler-exchange-dbinit",
+                                  "taler-exchange-dbinit",
+                                  "-c", config_filename,
+                                  "-r",
+                                  NULL);
+  if (NULL == proc)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to run `taler-exchange-dbinit`,"
+                " is your PATH correct?\n");
+    return GNUNET_NO;
+  }
+  if (GNUNET_SYSERR ==
+      GNUNET_OS_process_wait_status (proc,
+                                     &type,
+                                     &code))
+  {
+    GNUNET_break (0);
+    GNUNET_OS_process_destroy (proc);
+    return GNUNET_SYSERR;
+  }
+  GNUNET_OS_process_destroy (proc);
+  if ( (type == GNUNET_OS_PROCESS_EXITED) &&
+       (0 != code) )
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to setup (exchange) database\n");
+    return GNUNET_NO;
+  }
+  if ( (type != GNUNET_OS_PROCESS_EXITED) ||
+       (0 != code) )
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Unexpected error running"
+		" `taler-exchange-dbinit'!\n");
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Run `taler-auditor-dbinit -r` (reset auditor database).
+ *
+ * @param config_filename configuration file to use
+ * @return #GNUNET_OK on success
+ */
+int
+TALER_TESTING_auditor_db_reset (const char *config_filename)
+{
+  struct GNUNET_OS_Process *proc;
+  enum GNUNET_OS_ProcessStatusType type;
+  unsigned long code;
+
+  proc = GNUNET_OS_start_process (GNUNET_NO,
+                                  GNUNET_OS_INHERIT_STD_ALL,
+                                  NULL, NULL, NULL,
+                                  "taler-auditor-dbinit",
+                                  "taler-auditor-dbinit",
+                                  "-c", config_filename,
+                                  "-r",
+                                  NULL);
+  if (NULL == proc)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to run `taler-auditor-dbinit`,"
+                " is your PATH correct?\n");
+    return GNUNET_NO;
+  }
+  if (GNUNET_SYSERR ==
+      GNUNET_OS_process_wait_status (proc,
+                                     &type,
+                                     &code))
+  {
+    GNUNET_break (0);
+    GNUNET_OS_process_destroy (proc);
+    return GNUNET_SYSERR;
+  }
+  GNUNET_OS_process_destroy (proc);
+  if ( (type == GNUNET_OS_PROCESS_EXITED) &&
+       (0 != code) )
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Failed to setup (auditor) database\n");
+    return GNUNET_NO;
+  }
+  if ( (type != GNUNET_OS_PROCESS_EXITED) ||
+       (0 != code) )
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+		"Unexpected error running"
+		" `taler-auditor-dbinit'!\n");
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Type of closure for
+ * #sign_keys_for_exchange.
+ */
+struct SignInfo
+{
+  /**
+   * Set to the base URL of the exchange. To be free'd
+   * by the caller.
+   */
+  char *exchange_base_url;
+
+  /**
+   * Set to the auditor's base URL. To be free'd by the caller.
+   */
+  char *auditor_base_url;
+
+  /**
+   * Name of the configuration file to use.
+   */
+  const char *config_filename;
+
+  /**
+   * Must be set to input file with the data to be signed before
+   * calling #TALER_TESTING_sign_keys_for_exchange.
+   */
+  const char *auditor_sign_input_filename;
+};
+
+
+/**
+ * Sign the keys for an exchange given configuration @a cfg.
+ * The information to be signed must be in a file "auditor.in".
+ *
+ * @param cls[in,out] a `struct SignInfo` with
+ *       further paramters
+ * @param cfg configuration to use
+ * @return #GNUNET_OK on success
+ */
+static int
+sign_keys_for_exchange (void *cls,
+			const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  struct SignInfo *si = cls;
+  char *test_home_dir;
+  char *signed_keys_out;
+  char *exchange_master_pub;
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "exchange",
+                                             "BASE_URL",
+                                             &si->exchange_base_url))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
+                               "exchange",
+                               "BASE_URL");
+    si->exchange_base_url = NULL;
+    return GNUNET_NO;
+  }
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "auditor",
+                                             "BASE_URL",
+                                             &si->auditor_base_url))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
+                               "auditor",
+                               "BASE_URL");
+    GNUNET_free (si->exchange_base_url);
+    si->exchange_base_url = NULL;
+    si->auditor_base_url = NULL;
+    return GNUNET_SYSERR;
+  }
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_filename (cfg,
+                                               "paths",
+                                               "TALER_TEST_HOME",
+                                               &test_home_dir))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "paths",
+                               "TALER_TEST_HOME");
+    GNUNET_free (si->exchange_base_url);
+    GNUNET_free (si->auditor_base_url);
+    si->exchange_base_url = NULL;
+    si->auditor_base_url = NULL;
+    return GNUNET_SYSERR;
+  }
+
+  GNUNET_asprintf (&signed_keys_out,
+                   "%s/.local/share/taler/auditors/auditor.out",
+                   test_home_dir);
+  GNUNET_free (test_home_dir);
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "exchange",
+                                             "MASTER_PUBLIC_KEY",
+                                             &exchange_master_pub))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "exchange",
+                               "MASTER_PUBLIC_KEY");
+    GNUNET_free (si->exchange_base_url);
+    GNUNET_free (si->auditor_base_url);
+    si->exchange_base_url = NULL;
+    si->auditor_base_url = NULL;
+    GNUNET_free (signed_keys_out);
+    return GNUNET_SYSERR;
+  }
+  if (GNUNET_OK !=
+      TALER_TESTING_run_auditor_exchange (si->config_filename,
+                                          exchange_master_pub,
+                                          si->exchange_base_url,
+                                          GNUNET_NO))
+  {
+    GNUNET_free (si->exchange_base_url);
+    GNUNET_free (si->auditor_base_url);
+    si->exchange_base_url = NULL;
+    si->auditor_base_url = NULL;
+    return GNUNET_NO;
+  }
+
+  if (GNUNET_OK !=
+      TALER_TESTING_run_auditor_sign (si->config_filename,
+				      exchange_master_pub,
+				      si->auditor_base_url,
+				      si->auditor_sign_input_filename,
+				      signed_keys_out))
+  {
+    GNUNET_free (si->exchange_base_url);
+    GNUNET_free (si->auditor_base_url);
+    si->exchange_base_url = NULL;
+    si->auditor_base_url = NULL;
+    return GNUNET_NO;
+  }
+  GNUNET_free (signed_keys_out);
+  GNUNET_free (exchange_master_pub);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Prepare launching an exchange.  Checks that the configured
+ * port is available, runs taler-exchange-keyup,
+ * taler-auditor-sign and taler-exchange-dbinit.  Does NOT
+ * launch the exchange process itself.
+ *
+ * @param config_filename configuration file to use
+ * @param auditor_base_url[out] will be set to the auditor base url,
+ *        if the config has any; otherwise it will be set to
+ *        NULL.
+ * @param exchange_base_url[out] will be set to the exchange base url,
+ *        if the config has any; otherwise it will be set to
+ *        NULL.
+ * @return #GNUNET_OK on success, #GNUNET_NO if test should be
+ *         skipped, #GNUNET_SYSERR on test failure
+ */
+int
+TALER_TESTING_prepare_exchange (const char *config_filename,
+				char **auditor_base_url,
+				char **exchange_base_url)
+{
+  struct SignInfo si = {
+    .config_filename = config_filename,
+    .exchange_base_url = NULL,
+    .auditor_base_url = NULL,
+    .auditor_sign_input_filename = "auditor.in"
+  };
+
+  if (GNUNET_OK !=
+      TALER_TESTING_run_keyup (config_filename,
+			       si.auditor_sign_input_filename))
+    return GNUNET_NO;
+  if (GNUNET_OK !=
+      TALER_TESTING_exchange_db_reset (config_filename))
+    return GNUNET_NO;
+  if (GNUNET_OK !=
+      TALER_TESTING_auditor_db_reset (config_filename))
+    return GNUNET_NO;
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_parse_and_run (config_filename,
+					  &sign_keys_for_exchange,
+					  &si))
+    return GNUNET_NO;
+  *exchange_base_url = si.exchange_base_url;
+  *auditor_base_url = si.auditor_base_url;
+  return GNUNET_OK;
+}
+
+
+/**
+ * Find denomination key matching the given amount.
+ *
+ * @param keys array of keys to search
+ * @param amount coin value to look for
+ * @return NULL if no matching key was found
+ */
+const struct TALER_EXCHANGE_DenomPublicKey *
+TALER_TESTING_find_pk (const struct TALER_EXCHANGE_Keys *keys,
+                       const struct TALER_Amount *amount)
+{
+  struct GNUNET_TIME_Absolute now;
+  struct TALER_EXCHANGE_DenomPublicKey *pk;
+  char *str;
+
+  now = GNUNET_TIME_absolute_get ();
+  for (unsigned int i=0;i<keys->num_denom_keys;i++)
+  {
+    pk = &keys->denom_keys[i];
+    if ( (0 == TALER_amount_cmp (amount,
+                                 &pk->value)) &&
+         (now.abs_value_us >= pk->valid_from.abs_value_us) &&
+         (now.abs_value_us <
+          pk->withdraw_valid_until.abs_value_us) )
+      return pk;
+  }
+  /* do 2nd pass to check if expiration times are to blame for
+   * failure */
+  str = TALER_amount_to_string (amount);
+  for (unsigned int i=0;i<keys->num_denom_keys;i++)
+  {
+    pk = &keys->denom_keys[i];
+    if ( (0 == TALER_amount_cmp (amount,
+                                 &pk->value)) &&
+         ( (now.abs_value_us < pk->valid_from.abs_value_us) ||
+           (now.abs_value_us >
+            pk->withdraw_valid_until.abs_value_us) ) )
+    {
+      GNUNET_log
+        (GNUNET_ERROR_TYPE_WARNING,
+         "Have denomination key for `%s', but with wrong"
+         " expiration range %llu vs [%llu,%llu)\n",
+         str,
+         (unsigned long long) now.abs_value_us,
+         (unsigned long long) pk->valid_from.abs_value_us,
+         (unsigned long long)
+           pk->withdraw_valid_until.abs_value_us);
+      GNUNET_free (str);
+      return NULL;
+    }
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+              "No denomination key for amount %s found\n",
+              str);
+  GNUNET_free (str);
+  return NULL;
+}
+
+
+/**
+ * Wait for the exchange to have started. Waits for at
+ * most 10s, after that returns 77 to indicate an error.
+ *
+ * @param base_url what URL should we expect the exchange
+ *        to be running at
+ * @return 0 on success
+ */
+int
+TALER_TESTING_wait_exchange_ready (const char *base_url)
+{
+  char *wget_cmd;
+  unsigned int iter;
+
+  GNUNET_asprintf (&wget_cmd,
+                   "wget -q -t 1 -T 1 %skeys"
+                   " -o /dev/null -O /dev/null",
+                   base_url); // make sure ends with '/'
+  /* give child time to start and bind against the socket */
+  fprintf (stderr,
+           "Waiting for `taler-exchange-httpd' to be ready\n");
+  iter = 0;
+  do
+    {
+      if (10 == iter)
+      {
+	fprintf (stderr,
+		 "Failed to launch `taler-exchange-httpd' (or `wget')\n");
+        GNUNET_free (wget_cmd);
+	return 77;
+      }
+      fprintf (stderr, ".\n");
+      sleep (1);
+      iter++;
+    }
+  while (0 != system (wget_cmd));
+  GNUNET_free (wget_cmd);
+  return 0;
+}
+
+
+/**
+ * Wait for the auditor to have started. Waits for at
+ * most 10s, after that returns 77 to indicate an error.
+ *
+ * @param base_url what URL should we expect the auditor
+ *        to be running at
+ * @return 0 on success
+ */
+int
+TALER_TESTING_wait_auditor_ready (const char *base_url)
+{
+  char *wget_cmd;
+  unsigned int iter;
+
+  GNUNET_asprintf (&wget_cmd,
+                   "wget -q -t 1 -T 1 %sversion"
+                   " -o /dev/null -O /dev/null",
+                   base_url); // make sure ends with '/'
+  /* give child time to start and bind against the socket */
+  fprintf (stderr,
+           "Waiting for `taler-auditor-httpd' to be ready\n");
+  iter = 0;
+  do
+    {
+      if (10 == iter)
+      {
+	fprintf (stderr,
+		 "Failed to launch `taler-auditor-httpd' (or `wget')\n");
+        GNUNET_free (wget_cmd);
+	return 77;
+      }
+      fprintf (stderr, ".\n");
+      sleep (1);
+      iter++;
+    }
+  while (0 != system (wget_cmd));
+  GNUNET_free (wget_cmd);
+  return 0;
+}
+
+
+/**
+ * Initialize scheduler loop and curl context for the testcase
+ * including starting and stopping the exchange using the given
+ * configuration file.
+ *
+ * @param main_cb routine containing all the commands to run.
+ * @param main_cb_cls closure for @a main_cb, typically NULL.
+ * @param config_file configuration file for the test-suite.
+ *
+ * @return #GNUNET_OK if all is okay, != #GNUNET_OK otherwise.
+ *         non-#GNUNET_OK codes are #GNUNET_SYSERR most of the
+ *         time.
+ */
+int
+TALER_TESTING_setup_with_exchange (TALER_TESTING_Main main_cb,
+                                   void *main_cb_cls,
+                                   const char *config_filename)
+{
+  struct TALER_TESTING_SetupContext setup_ctx = {
+    .config_filename = config_filename,
+    .main_cb = main_cb,
+    .main_cb_cls = main_cb_cls
+  };
+  int result;
+
+  if (GNUNET_OK !=
+      (result = GNUNET_CONFIGURATION_parse_and_run (config_filename,
+                                                    &TALER_TESTING_setup_with_exchange_cfg,
+                                                    &setup_ctx)))
+    return result;
+  return GNUNET_OK;
+}
+
+
+/**
+ * Initialize scheduler loop and curl context for the test case
+ * including starting and stopping the exchange using the given
+ * configuration file.
+ *
+ * @param cls must be a `struct TALER_TESTING_SetupContext *`
+ * @param cfg configuration to use.
+ * @return #GNUNET_OK if no errors occurred.
+ */
+int
+TALER_TESTING_setup_with_exchange_cfg (void *cls,
+                                       const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  const struct TALER_TESTING_SetupContext *setup_ctx = cls;
+  struct GNUNET_OS_Process *exchanged;
+  unsigned long long port;
+  char *serve;
+  char *base_url;
+  int result;
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "exchange",
+                                             "SERVE",
+                                             &serve))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "exchange",
+                               "SERVE");
+    return GNUNET_NO;
+  }
+
+  if (0 == strcmp ("tcp", serve))
+  {
+    if (GNUNET_OK !=
+        GNUNET_CONFIGURATION_get_value_number (cfg,
+                                               "exchange",
+                                               "PORT",
+                                               &port))
+    {
+      GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                                 "exchange",
+                                 "PORT");
+      GNUNET_free (serve);
+      return GNUNET_NO;
+    }
+
+    if (GNUNET_OK !=
+        GNUNET_NETWORK_test_port_free (IPPROTO_TCP,
+  				     (uint16_t) port))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                  "Required port %llu not available, skipping.\n",
+                  port);
+      GNUNET_free (serve);
+      return GNUNET_NO;
+    }
+  }
+  GNUNET_free (serve);
+  exchanged = GNUNET_OS_start_process (GNUNET_NO,
+                                       GNUNET_OS_INHERIT_STD_ALL,
+                                       NULL, NULL, NULL,
+                                       "taler-exchange-httpd",
+                                       "taler-exchange-httpd",
+                                       "-c", setup_ctx->config_filename,
+                                       "-i",
+                                       NULL);
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "exchange",
+                                             "BASE_URL",
+                                             &base_url))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "exchange",
+                               "BASE_URL");
+    return GNUNET_NO;
+  }
+
+  if (0 != TALER_TESTING_wait_exchange_ready (base_url))
+  {
+    GNUNET_free (base_url);
+    return 77;
+  }
+  GNUNET_free (base_url);
+
+  /* NOTE: this call blocks.  */
+  result = TALER_TESTING_setup (setup_ctx->main_cb,
+                                setup_ctx->main_cb_cls,
+                                setup_ctx->config_filename,
+                                exchanged,
+                                GNUNET_YES);
+  GNUNET_break (0 ==
+                GNUNET_OS_process_kill (exchanged,
+                                        SIGTERM));
+  GNUNET_break (GNUNET_OK ==
+                GNUNET_OS_process_wait (exchanged));
+  GNUNET_OS_process_destroy (exchanged);
+  return result;
+}
+
+
+/**
+ * Initialize scheduler loop and curl context for the test case
+ * including starting and stopping the auditor and exchange using the
+ * given configuration file.
+ *
+ * @param cls must be a `struct TALER_TESTING_SetupContext *`
+ * @param cfg configuration to use.
+ * @return #GNUNET_OK if no errors occurred.
+ */
+int
+TALER_TESTING_setup_with_auditor_and_exchange_cfg (void *cls,
+                                                   const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  const struct TALER_TESTING_SetupContext *setup_ctx = cls;
+  struct GNUNET_OS_Process *auditord;
+  unsigned long long port;
+  char *serve;
+  char *base_url;
+  int result;
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "auditor",
+                                             "SERVE",
+                                             &serve))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "auditor",
+                               "SERVE");
+    return GNUNET_NO;
+  }
+
+  if (0 == strcmp ("tcp", serve))
+  {
+    if (GNUNET_OK !=
+        GNUNET_CONFIGURATION_get_value_number (cfg,
+                                               "auditor",
+                                               "PORT",
+                                               &port))
+    {
+      GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                                 "auditor",
+                                 "PORT");
+      GNUNET_free (serve);
+      return GNUNET_NO;
+    }
+
+    if (GNUNET_OK !=
+        GNUNET_NETWORK_test_port_free (IPPROTO_TCP,
+  				     (uint16_t) port))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                  "Required port %llu not available, skipping.\n",
+                  port);
+      GNUNET_free (serve);
+      return GNUNET_NO;
+    }
+  }
+  GNUNET_free (serve);
+  auditord = GNUNET_OS_start_process (GNUNET_NO,
+                                      GNUNET_OS_INHERIT_STD_ALL,
+                                      NULL, NULL, NULL,
+                                      "taler-auditor-httpd",
+                                      "taler-auditor-httpd",
+                                      "-c", setup_ctx->config_filename,
+                                      NULL);
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             "auditor",
+                                             "BASE_URL",
+                                             &base_url))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "auditor",
+                               "BASE_URL");
+    return GNUNET_NO;
+  }
+
+  if (0 != TALER_TESTING_wait_auditor_ready (base_url))
+  {
+    GNUNET_free (base_url);
+    GNUNET_break (0 ==
+                  GNUNET_OS_process_kill (auditord,
+                                          SIGTERM));
+    GNUNET_break (GNUNET_OK ==
+                  GNUNET_OS_process_wait (auditord));
+    GNUNET_OS_process_destroy (auditord);
+    return 77;
+  }
+  GNUNET_free (base_url);
+
+  /* NOTE: this call blocks.  */
+  result = TALER_TESTING_setup_with_exchange_cfg ((void *) setup_ctx,
+                                                  cfg);
+  GNUNET_break (0 ==
+                GNUNET_OS_process_kill (auditord,
+                                        SIGTERM));
+  GNUNET_break (GNUNET_OK ==
+                GNUNET_OS_process_wait (auditord));
+  GNUNET_OS_process_destroy (auditord);
+  return result;
+}
+
+
+/**
+ * Initialize scheduler loop and curl context for the test case
+ * including starting and stopping the auditor and exchange using the
+ * given configuration file.
+ *
+ * @param main_cb main method.
+ * @param main_cb_cls main method closure.
+ * @param config_filename configuration file name.  Is is used
+ *        by both this function and the exchange itself.  In the
+ *        first case it gives out the exchange port number and
+ *        the exchange base URL so as to check whether the port
+ *        is available and the exchange responds when requested
+ *        at its base URL.
+ * @return #GNUNET_OK if no errors occurred.
+ */
+int
+TALER_TESTING_setup_with_auditor_and_exchange (TALER_TESTING_Main main_cb,
+                                               void *main_cb_cls,
+                                               const char *config_file)
+{
+  struct TALER_TESTING_SetupContext setup_ctx = {
+    .config_filename = config_file,
+    .main_cb = main_cb,
+    .main_cb_cls = main_cb_cls
+  };
+
+  return GNUNET_CONFIGURATION_parse_and_run (config_file,
+                                             &TALER_TESTING_setup_with_auditor_and_exchange_cfg,
+                                             &setup_ctx);
+}
+
+
+/**
+ * Test port in URL string for availability.
+ */
+int
+TALER_TESTING_url_port_free (const char *url)
+{
+  const char *port;
+  long pnum;
+
+  port = strrchr (url,
+                  (unsigned char) ':');
+  if (NULL == port)
+    pnum = 80;
+  else
+    pnum = strtol (port + 1, NULL, 10);
+  if (GNUNET_OK !=
+      GNUNET_NETWORK_test_port_free (IPPROTO_TCP,
+				     pnum))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "Port %u not available.\n",
+                (unsigned int) pnum);
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Allocate and return a piece of wire-details.  Combines
+ * the @a account_no and the @a bank_url to a
+ * @a payto://-URL and adds some salt to create the JSON.
+ *
+ * @param account_no account number
+ * @param bank_url the bank_url (FIXME/WARNING: shouldn't this be a _hostname_ ??)
+ * @return JSON describing the account, including the
+ *         payto://-URL of the account, must be manually decref'd
+ */
+json_t *
+TALER_TESTING_make_wire_details (unsigned long long account_no,
+                                 const char *bank_url)
+{
+  char *payto;
+  json_t *ret;
+
+  GNUNET_asprintf (&payto,
+                   "payto://x-taler-bank/%s/%llu",
+                   bank_url,
+                   account_no);
+  ret = json_pack ("{s:s, s:s}",
+                   "url", payto,
+                   "salt", "test-salt (must be constant for aggregation tests)");
+  GNUNET_free (payto);
+  return ret;
+}
+
+
+/**
+ * Prepare launching a fakebank.  Check that the configuration
+ * file has the right option, and that the port is available.
+ * If everything is OK, return the configured URL of the fakebank.
+ *
+ * @param config_filename configuration file to use
+ * @param config_section which account to use (must match x-taler-bank)
+ * @return NULL on error, fakebank URL otherwise
+ */
+char *
+TALER_TESTING_prepare_fakebank (const char *config_filename,
+                                const char *config_section)
+{
+  struct GNUNET_CONFIGURATION_Handle *cfg;
+  char *payto_url;
+  char *fakebank_url;
+  const char *start;
+  const char *end;
+
+  cfg = GNUNET_CONFIGURATION_create ();
+  if (GNUNET_OK != GNUNET_CONFIGURATION_load (cfg,
+                                              config_filename))
+    return NULL;
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             config_section,
+                                             "URL",
+                                             &payto_url))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_WARNING,
+                               config_section,
+                               "URL");
+    GNUNET_CONFIGURATION_destroy (cfg);
+    return NULL;
+  }
+  GNUNET_CONFIGURATION_destroy (cfg);
+  if (0 != strncasecmp (payto_url,
+                        "payto://x-taler-bank/",
+                        strlen ("payto://x-taler-bank/")))
+  {
+    GNUNET_log_config_invalid
+      (GNUNET_ERROR_TYPE_WARNING,
+       config_section,
+       "URL",
+       "expected `x-taler-bank' payto://-URL");
+    GNUNET_CONFIGURATION_destroy (cfg);
+    GNUNET_free (payto_url);
+    return NULL;
+  }
+  start = &payto_url [strlen ("payto://x-taler-bank/")];
+  end = strchr (start,
+                (unsigned char) '/');
+  if (NULL == end)
+    end = &start[strlen (start)];
+  fakebank_url = GNUNET_strndup (start,
+                                 end - start);
+  GNUNET_free (payto_url);
+  if (GNUNET_OK !=
+      TALER_TESTING_url_port_free (fakebank_url))
+  {
+    GNUNET_free (fakebank_url);
+    return NULL;
+  }
+  return fakebank_url;
+}
+
+/* end of testing_api_helpers.c */