-more clean up of auditor api: atomization complete

11 files changed, 363 insertions, 555 deletions

diff --git a/src/include/taler_auditor_service.h b/src/include/taler_auditor_service.h
index 2c6685c1c..3d8ca9efb 100644
--- a/src/include/taler_auditor_service.h
+++ b/src/include/taler_auditor_service.h
@@ -28,12 +28,12 @@
 #include <gnunet/gnunet_curl_lib.h>
 
 
-/* *********************  /version *********************** */
+/* *********************  /config *********************** */
 
 /**
- * @brief Information we get from the auditor about auditors.
+ * @brief Information we get from the auditor about itself.
  */
-struct TALER_AUDITOR_VersionInformation
+struct TALER_AUDITOR_ConfigInformation
 {
   /**
    * Public key of the auditing institution.  Wallets and merchants
@@ -147,9 +147,9 @@ struct TALER_AUDITOR_HttpResponse
 
 
 /**
- * Response to /version request.
+ * Response to /config request.
  */
-struct TALER_AUDITOR_VersionResponse
+struct TALER_AUDITOR_ConfigResponse
 {
   /**
    * HTTP response.
@@ -174,11 +174,12 @@ struct TALER_AUDITOR_VersionResponse
       enum TALER_AUDITOR_VersionCompatibility compat;
 
       /**
-       * Version data returned by /config.
+       * Config data returned by /config.
        */
-      struct TALER_AUDITOR_VersionInformation vi;
+      struct TALER_AUDITOR_ConfigInformation vi;
 
     } ok;
+
   } details;
 
 };
@@ -191,46 +192,45 @@ struct TALER_AUDITOR_VersionResponse
  * @param vr response data
  */
 typedef void
-(*TALER_AUDITOR_VersionCallback) (
+(*TALER_AUDITOR_ConfigCallback) (
   void *cls,
-  const struct TALER_AUDITOR_VersionResponse *vr);
+  const struct TALER_AUDITOR_ConfigResponse *vr);
 
 
 /**
  * @brief Handle to the auditor.  This is where we interact with
  * a particular auditor and keep the per-auditor information.
  */
-struct TALER_AUDITOR_Handle;
+struct TALER_AUDITOR_GetConfigHandle;
 
 
 /**
- * Initialise a connection to the auditor. Will connect to the
+ * Obtain meta data about an auditor. Will connect to the
  * auditor and obtain information about the auditor's master public
  * key and the auditor's auditor.  The respective information will
- * be passed to the @a version_cb once available, and all future
- * interactions with the auditor will be checked to be signed
- * (where appropriate) by the respective master key.
+ * be passed to the @a config_cb once available.
  *
  * @param ctx the context for CURL requests
  * @param url HTTP base URL for the auditor
- * @param version_cb function to call with the auditor's version information
- * @param version_cb_cls closure for @a version_cb
+ * @param config_cb function to call with the auditor's config information
+ * @param config_cb_cls closure for @a config_cb
  * @return the auditor handle; NULL upon error
  */
-struct TALER_AUDITOR_Handle *
-TALER_AUDITOR_connect (struct GNUNET_CURL_Context *ctx,
-                       const char *url,
-                       TALER_AUDITOR_VersionCallback version_cb,
-                       void *version_cb_cls);
+struct TALER_AUDITOR_GetConfigHandle *
+TALER_AUDITOR_get_config (struct GNUNET_CURL_Context *ctx,
+                          const char *url,
+                          TALER_AUDITOR_ConfigCallback config_cb,
+                          void *config_cb_cls);
 
 
 /**
- * Disconnect from the auditor.
+ * Cancel auditor config request.
  *
  * @param auditor the auditor handle
  */
 void
-TALER_AUDITOR_disconnect (struct TALER_AUDITOR_Handle *auditor);
+TALER_AUDITOR_get_config_cancel (struct
+                                 TALER_AUDITOR_GetConfigHandle *auditor);
 
 
 /**
@@ -271,11 +271,10 @@ typedef void
  * that the response is well-formed.  If the auditor's reply is not
  * well-formed, we return an HTTP status code of zero to @a cb.
  *
- * We also verify that the @a exchange_sig is valid for this deposit-confirmation
- * request, and that the @a master_sig is a valid signature for @a
- * exchange_pub.  Also, the @a auditor must be ready to operate (i.e.  have
- * finished processing the /version reply).  If either check fails, we do
- * NOT initiate the transaction with the auditor and instead return NULL.
+ * We also verify that the @a exchange_sig is valid for this
+ * deposit-confirmation request, and that the @a master_sig is a valid
+ * signature for @a exchange_pub.  If the check fails, we do NOT initiate the
+ * transaction with the auditor and instead return NULL.
  *
  * @param ctx the context for CURL requests
  * @param url HTTP base URL for the auditor
diff --git a/src/include/taler_testing_lib.h b/src/include/taler_testing_lib.h
index 175d25e66..2c9f58596 100644
--- a/src/include/taler_testing_lib.h
+++ b/src/include/taler_testing_lib.h
@@ -2692,7 +2692,6 @@ TALER_TESTING_get_trait (const struct TALER_TESTING_Trait *traits,
   op (fresh_coins, const struct TALER_TESTING_FreshCoinData *)     \
   op (claim_token, const struct TALER_ClaimTokenP)                 \
   op (relative_time, const struct GNUNET_TIME_Relative)            \
-  op (auditor, struct TALER_AUDITOR_Handle)                        \
   op (exchange, struct TALER_EXCHANGE_Handle)                      \
   op (fakebank, struct TALER_FAKEBANK_Handle)                      \
   op (process, struct GNUNET_OS_Process *)
diff --git a/src/lib/Makefile.am b/src/lib/Makefile.am
index 529a2d019..2c9031428 100644
--- a/src/lib/Makefile.am
+++ b/src/lib/Makefile.am
@@ -96,7 +96,7 @@ libtalerauditor_la_LDFLAGS = \
   -no-undefined
 libtalerauditor_la_SOURCES = \
   auditor_api_curl_defaults.c auditor_api_curl_defaults.h \
-  auditor_api_handle.c auditor_api_handle.h \
+  auditor_api_get_config.c \
   auditor_api_deposit_confirmation.c \
   auditor_api_exchanges.c
 libtalerauditor_la_LIBADD = \
diff --git a/src/lib/auditor_api_deposit_confirmation.c b/src/lib/auditor_api_deposit_confirmation.c
index 21479c106..0b0f4dd4d 100644
--- a/src/lib/auditor_api_deposit_confirmation.c
+++ b/src/lib/auditor_api_deposit_confirmation.c
@@ -25,9 +25,10 @@
 #include <gnunet/gnunet_util_lib.h>
 #include <gnunet/gnunet_json_lib.h>
 #include <gnunet/gnunet_curl_lib.h>
+#include "taler_util.h"
+#include "taler_curl_lib.h"
 #include "taler_json_lib.h"
 #include "taler_auditor_service.h"
-#include "auditor_api_handle.h"
 #include "taler_signatures.h"
 #include "auditor_api_curl_defaults.h"
 
diff --git a/src/lib/auditor_api_exchanges.c b/src/lib/auditor_api_exchanges.c
index 8acf59467..897dfe60f 100644
--- a/src/lib/auditor_api_exchanges.c
+++ b/src/lib/auditor_api_exchanges.c
@@ -27,7 +27,8 @@
 #include <gnunet/gnunet_curl_lib.h>
 #include "taler_json_lib.h"
 #include "taler_auditor_service.h"
-#include "auditor_api_handle.h"
+#include "taler_util.h"
+#include "taler_curl_lib.h"
 #include "taler_signatures.h"
 #include "auditor_api_curl_defaults.h"
 
diff --git a/src/lib/auditor_api_get_config.c b/src/lib/auditor_api_get_config.c
new file mode 100644
index 000000000..ede702a0d
--- /dev/null
+++ b/src/lib/auditor_api_get_config.c
@@ -0,0 +1,288 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2014-2023 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 lib/auditor_api_get_config.c
+ * @brief Implementation of /config for the auditor's HTTP API
+ * @author Sree Harsha Totakura <sreeharsha@totakura.in>
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <microhttpd.h>
+#include <gnunet/gnunet_curl_lib.h>
+#include "taler_json_lib.h"
+#include "taler_auditor_service.h"
+#include "taler_signatures.h"
+#include "auditor_api_curl_defaults.h"
+
+
+/**
+ * Which revision of the Taler auditor protocol is implemented
+ * by this library?  Used to determine compatibility.
+ */
+#define TALER_PROTOCOL_CURRENT 0
+
+/**
+ * How many revisions back are we compatible to?
+ */
+#define TALER_PROTOCOL_AGE 0
+
+
+/**
+ * Log error related to CURL operations.
+ *
+ * @param type log level
+ * @param function which function failed to run
+ * @param code what was the curl error code
+ */
+#define CURL_STRERROR(type, function, code)      \
+  GNUNET_log (type, "Curl function `%s' has failed at `%s:%d' with error: %s", \
+              function, __FILE__, __LINE__, curl_easy_strerror (code));
+
+
+/**
+ * Handle for the get config request.
+ */
+struct TALER_AUDITOR_GetConfigHandle
+{
+  /**
+   * The context of this handle
+   */
+  struct GNUNET_CURL_Context *ctx;
+
+  /**
+   * Function to call with the auditor's certification data,
+   * NULL if this has already been done.
+   */
+  TALER_AUDITOR_ConfigCallback config_cb;
+
+  /**
+   * Closure to pass to @e config_cb.
+   */
+  void *config_cb_cls;
+
+  /**
+   * Data for the request to get the /config of a auditor,
+   * NULL once we are past stage #MHS_INIT.
+   */
+  struct GNUNET_CURL_Job *vr;
+
+  /**
+   * The url for the @e vr job.
+   */
+  char *vr_url;
+
+};
+
+
+/* ***************** Internal /config fetching ************* */
+
+/**
+ * Decode the JSON in @a resp_obj from the /config response and store the data
+ * in the @a key_data.
+ *
+ * @param[in] resp_obj JSON object to parse
+ * @param[in,out] auditor where to store the results we decoded
+ * @param[out] vc where to store config compatibility data
+ * @return #TALER_EC_NONE on success
+ */
+static enum TALER_ErrorCode
+decode_config_json (const json_t *resp_obj,
+                    struct TALER_AUDITOR_ConfigInformation *vi,
+                    enum TALER_AUDITOR_VersionCompatibility *vc)
+{
+  unsigned int age;
+  unsigned int revision;
+  unsigned int current;
+  char dummy;
+  const char *ver;
+  struct GNUNET_JSON_Specification spec[] = {
+    GNUNET_JSON_spec_string ("version",
+                             &ver),
+    GNUNET_JSON_spec_fixed_auto ("auditor_public_key",
+                                 &vi->auditor_pub),
+    GNUNET_JSON_spec_end ()
+  };
+
+  if (JSON_OBJECT != json_typeof (resp_obj))
+  {
+    GNUNET_break_op (0);
+    return TALER_EC_GENERIC_JSON_INVALID;
+  }
+  /* check the config */
+  if (GNUNET_OK !=
+      GNUNET_JSON_parse (resp_obj,
+                         spec,
+                         NULL, NULL))
+  {
+    GNUNET_break_op (0);
+    return TALER_EC_GENERIC_JSON_INVALID;
+  }
+  if (3 != sscanf (ver,
+                   "%u:%u:%u%c",
+                   &current,
+                   &revision,
+                   &age,
+                   &dummy))
+  {
+    GNUNET_break_op (0);
+    return TALER_EC_GENERIC_VERSION_MALFORMED;
+  }
+  vi->version = ver;
+  *vc = TALER_AUDITOR_VC_MATCH;
+  if (TALER_PROTOCOL_CURRENT < current)
+  {
+    *vc |= TALER_AUDITOR_VC_NEWER;
+    if (TALER_PROTOCOL_CURRENT < current - age)
+      *vc |= TALER_AUDITOR_VC_INCOMPATIBLE;
+  }
+  if (TALER_PROTOCOL_CURRENT > current)
+  {
+    *vc |= TALER_AUDITOR_VC_OLDER;
+    if (TALER_PROTOCOL_CURRENT - TALER_PROTOCOL_AGE > current)
+      *vc |= TALER_AUDITOR_VC_INCOMPATIBLE;
+  }
+  return TALER_EC_NONE;
+}
+
+
+/**
+ * Callback used when downloading the reply to a /config request
+ * is complete.
+ *
+ * @param cls the `struct TALER_AUDITOR_GetConfigHandle`
+ * @param response_code HTTP response code, 0 on error
+ * @param gresp_obj parsed JSON result, NULL on error, must be a `const json_t *`
+ */
+static void
+config_completed_cb (void *cls,
+                     long response_code,
+                     const void *gresp_obj)
+{
+  struct TALER_AUDITOR_GetConfigHandle *auditor = cls;
+  const json_t *resp_obj = gresp_obj;
+  struct TALER_AUDITOR_ConfigResponse vr = {
+    .hr.reply = resp_obj,
+    .hr.http_status = (unsigned int) response_code
+  };
+
+  auditor->vr = NULL;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received config from URL `%s' with status %ld.\n",
+              auditor->vr_url,
+              response_code);
+  switch (response_code)
+  {
+  case 0:
+    GNUNET_break_op (0);
+    vr.hr.ec = TALER_EC_INVALID;
+    break;
+  case MHD_HTTP_OK:
+    if (NULL == resp_obj)
+    {
+      GNUNET_break_op (0);
+      vr.hr.http_status = 0;
+      vr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+      break;
+    }
+    vr.hr.ec = decode_config_json (resp_obj,
+                                   &vr.details.ok.vi,
+                                   &vr.details.ok.compat);
+    if (TALER_EC_NONE != vr.hr.ec)
+    {
+      GNUNET_break_op (0);
+      vr.hr.http_status = 0;
+      break;
+    }
+    break;
+  case MHD_HTTP_INTERNAL_SERVER_ERROR:
+    vr.hr.ec = TALER_JSON_get_error_code (resp_obj);
+    vr.hr.hint = TALER_JSON_get_error_hint (resp_obj);
+    break;
+  default:
+    vr.hr.ec = TALER_JSON_get_error_code (resp_obj);
+    vr.hr.hint = TALER_JSON_get_error_hint (resp_obj);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Unexpected response code %u/%d\n",
+                (unsigned int) response_code,
+                (int) vr.hr.ec);
+    break;
+  }
+  auditor->config_cb (auditor->config_cb_cls,
+                      &vr);
+  TALER_AUDITOR_get_config_cancel (auditor);
+}
+
+
+struct TALER_AUDITOR_GetConfigHandle *
+TALER_AUDITOR_get_config (struct GNUNET_CURL_Context *ctx,
+                          const char *url,
+                          TALER_AUDITOR_ConfigCallback config_cb,
+                          void *config_cb_cls)
+{
+  struct TALER_AUDITOR_GetConfigHandle *auditor;
+  CURL *eh;
+
+  auditor = GNUNET_new (struct TALER_AUDITOR_GetConfigHandle);
+  auditor->config_cb = config_cb;
+  auditor->config_cb_cls = config_cb_cls;
+  auditor->ctx = ctx;
+  auditor->vr_url = TALER_url_join (url,
+                                    "config",
+                                    NULL);
+  if (NULL == auditor->vr_url)
+  {
+    GNUNET_break (0);
+    GNUNET_free (auditor->vr_url);
+    GNUNET_free (auditor);
+    return NULL;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Requesting auditor config with URL `%s'.\n",
+              auditor->vr_url);
+  eh = TALER_AUDITOR_curl_easy_get_ (auditor->vr_url);
+  if (NULL == eh)
+  {
+    GNUNET_break (0);
+    TALER_AUDITOR_get_config_cancel (auditor);
+    return NULL;
+  }
+  GNUNET_break (CURLE_OK ==
+                curl_easy_setopt (eh,
+                                  CURLOPT_TIMEOUT,
+                                  (long) 300));
+  auditor->vr = GNUNET_CURL_job_add (auditor->ctx,
+                                     eh,
+                                     &config_completed_cb,
+                                     auditor);
+  return auditor;
+}
+
+
+void
+TALER_AUDITOR_get_config_cancel (struct TALER_AUDITOR_GetConfigHandle *auditor)
+{
+  if (NULL != auditor->vr)
+  {
+    GNUNET_CURL_job_cancel (auditor->vr);
+    auditor->vr = NULL;
+  }
+  GNUNET_free (auditor->vr_url);
+  GNUNET_free (auditor);
+}
+
+
+/* end of auditor_api_get_config.c */
diff --git a/src/lib/auditor_api_handle.c b/src/lib/auditor_api_handle.c
deleted file mode 100644
index 318b63f94..000000000
--- a/src/lib/auditor_api_handle.c
+++ /dev/null
@@ -1,438 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2014-2022 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 lib/auditor_api_handle.c
- * @brief Implementation of the "handle" component of the auditor's HTTP API
- * @author Sree Harsha Totakura <sreeharsha@totakura.in>
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include <microhttpd.h>
-#include <gnunet/gnunet_curl_lib.h>
-#include "taler_json_lib.h"
-#include "taler_auditor_service.h"
-#include "taler_signatures.h"
-#include "auditor_api_handle.h"
-#include "auditor_api_curl_defaults.h"
-#include "backoff.h"
-
-/**
- * Which revision of the Taler auditor protocol is implemented
- * by this library?  Used to determine compatibility.
- */
-#define TALER_PROTOCOL_CURRENT 0
-
-/**
- * How many revisions back are we compatible to?
- */
-#define TALER_PROTOCOL_AGE 0
-
-
-/**
- * Log error related to CURL operations.
- *
- * @param type log level
- * @param function which function failed to run
- * @param code what was the curl error code
- */
-#define CURL_STRERROR(type, function, code)      \
-  GNUNET_log (type, "Curl function `%s' has failed at `%s:%d' with error: %s", \
-              function, __FILE__, __LINE__, curl_easy_strerror (code));
-
-/**
- * Stages of initialization for the `struct TALER_AUDITOR_Handle`
- */
-enum AuditorHandleState
-{
-  /**
-   * Just allocated.
-   */
-  MHS_INIT = 0,
-
-  /**
-   * Obtained the auditor's versioning data and version.
-   */
-  MHS_VERSION = 1,
-
-  /**
-   * Failed to initialize (fatal).
-   */
-  MHS_FAILED = 2
-};
-
-
-/**
- * Handle to the auditor
- */
-struct TALER_AUDITOR_Handle
-{
-  /**
-   * The context of this handle
-   */
-  struct GNUNET_CURL_Context *ctx;
-
-  /**
-   * The URL of the auditor (i.e. "http://auditor.taler.net/")
-   */
-  char *url;
-
-  /**
-   * Function to call with the auditor's certification data,
-   * NULL if this has already been done.
-   */
-  TALER_AUDITOR_VersionCallback version_cb;
-
-  /**
-   * Closure to pass to @e version_cb.
-   */
-  void *version_cb_cls;
-
-  /**
-   * Data for the request to get the /config of a auditor,
-   * NULL once we are past stage #MHS_INIT.
-   */
-  struct GNUNET_CURL_Job *vr;
-
-  /**
-   * The url for the @e vr job.
-   */
-  char *vr_url;
-
-  /**
-   * Task for retrying /config request.
-   */
-  struct GNUNET_SCHEDULER_Task *retry_task;
-
-  /**
-   * /config data of the auditor, only valid if
-   * @e handshake_complete is past stage #MHS_VERSION.
-   */
-  char *version;
-
-  /**
-   * Version information for the callback.
-   */
-  struct TALER_AUDITOR_VersionInformation vi;
-
-  /**
-   * Retry /config frequency.
-   */
-  struct GNUNET_TIME_Relative retry_delay;
-
-  /**
-   * Stage of the auditor's initialization routines.
-   */
-  enum AuditorHandleState state;
-
-};
-
-
-/* ***************** Internal /config fetching ************* */
-
-/**
- * Decode the JSON in @a resp_obj from the /config response and store the data
- * in the @a key_data.
- *
- * @param[in] resp_obj JSON object to parse
- * @param[in,out] auditor where to store the results we decoded
- * @param[out] vc where to store version compatibility data
- * @return #TALER_EC_NONE on success
- */
-static enum TALER_ErrorCode
-decode_version_json (const json_t *resp_obj,
-                     struct TALER_AUDITOR_Handle *auditor,
-                     enum TALER_AUDITOR_VersionCompatibility *vc)
-{
-  struct TALER_AUDITOR_VersionInformation *vi = &auditor->vi;
-  unsigned int age;
-  unsigned int revision;
-  unsigned int current;
-  char dummy;
-  const char *ver;
-  struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_string ("version",
-                             &ver),
-    GNUNET_JSON_spec_fixed_auto ("auditor_public_key",
-                                 &vi->auditor_pub),
-    GNUNET_JSON_spec_end ()
-  };
-
-  if (JSON_OBJECT != json_typeof (resp_obj))
-  {
-    GNUNET_break_op (0);
-    return TALER_EC_GENERIC_JSON_INVALID;
-  }
-  /* check the version */
-  if (GNUNET_OK !=
-      GNUNET_JSON_parse (resp_obj,
-                         spec,
-                         NULL, NULL))
-  {
-    GNUNET_break_op (0);
-    return TALER_EC_GENERIC_JSON_INVALID;
-  }
-  if (3 != sscanf (ver,
-                   "%u:%u:%u%c",
-                   &current,
-                   &revision,
-                   &age,
-                   &dummy))
-  {
-    GNUNET_break_op (0);
-    return TALER_EC_GENERIC_VERSION_MALFORMED;
-  }
-  GNUNET_free (auditor->version);
-  auditor->version = GNUNET_strdup (ver);
-  vi->version = auditor->version;
-  *vc = TALER_AUDITOR_VC_MATCH;
-  if (TALER_PROTOCOL_CURRENT < current)
-  {
-    *vc |= TALER_AUDITOR_VC_NEWER;
-    if (TALER_PROTOCOL_CURRENT < current - age)
-      *vc |= TALER_AUDITOR_VC_INCOMPATIBLE;
-  }
-  if (TALER_PROTOCOL_CURRENT > current)
-  {
-    *vc |= TALER_AUDITOR_VC_OLDER;
-    if (TALER_PROTOCOL_CURRENT - TALER_PROTOCOL_AGE > current)
-      *vc |= TALER_AUDITOR_VC_INCOMPATIBLE;
-  }
-  return TALER_EC_NONE;
-}
-
-
-/**
- * Initiate download of /config from the auditor.
- *
- * @param cls auditor where to download /config from
- */
-static void
-request_version (void *cls);
-
-
-/**
- * Callback used when downloading the reply to a /config request
- * is complete.
- *
- * @param cls the `struct TALER_AUDITOR_Handle`
- * @param response_code HTTP response code, 0 on error
- * @param gresp_obj parsed JSON result, NULL on error, must be a `const json_t *`
- */
-static void
-version_completed_cb (void *cls,
-                      long response_code,
-                      const void *gresp_obj)
-{
-  struct TALER_AUDITOR_Handle *auditor = cls;
-  const json_t *resp_obj = gresp_obj;
-  struct TALER_AUDITOR_VersionResponse vr = {
-    .hr.reply = resp_obj,
-    .hr.http_status = (unsigned int) response_code
-  };
-
-  auditor->vr = NULL;
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Received version from URL `%s' with status %ld.\n",
-              auditor->url,
-              response_code);
-  switch (response_code)
-  {
-  case 0:
-  case MHD_HTTP_INTERNAL_SERVER_ERROR:
-    /* NOTE: this design is debatable. We MAY want to throw this error at the
-       client. We may then still additionally internally re-try. */
-    GNUNET_assert (NULL == auditor->retry_task);
-    auditor->retry_delay = EXCHANGE_LIB_BACKOFF (auditor->retry_delay);
-    auditor->retry_task = GNUNET_SCHEDULER_add_delayed (auditor->retry_delay,
-                                                        &request_version,
-                                                        auditor);
-    return;
-  case MHD_HTTP_OK:
-    if (NULL == resp_obj)
-    {
-      GNUNET_break_op (0);
-      TALER_LOG_WARNING ("NULL body for a 200-OK /config\n");
-      vr.hr.http_status = 0;
-      vr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
-      break;
-    }
-    vr.hr.ec = decode_version_json (resp_obj,
-                                    auditor,
-                                    &vr.details.ok.compat);
-    if (TALER_EC_NONE != vr.hr.ec)
-    {
-      GNUNET_break_op (0);
-      vr.hr.http_status = 0;
-      break;
-    }
-    auditor->state = MHS_VERSION;
-    GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                "Auditor %s is ready!\n",
-                auditor->url);
-    vr.details.ok.vi = auditor->vi;
-    auditor->retry_delay = GNUNET_TIME_UNIT_ZERO; /* restart quickly */
-    break;
-  default:
-    vr.hr.ec = TALER_JSON_get_error_code (resp_obj);
-    vr.hr.hint = TALER_JSON_get_error_hint (resp_obj);
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                "Unexpected response code %u/%d\n",
-                (unsigned int) response_code,
-                (int) vr.hr.ec);
-    break;
-  }
-  if (MHD_HTTP_OK != response_code)
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                "/config failed for auditor %s: %u!\n",
-                auditor->url,
-                (unsigned int) response_code);
-    auditor->state = MHS_FAILED;
-  }
-  auditor->version_cb (auditor->version_cb_cls,
-                       &vr);
-}
-
-
-/**
- * Initiate download of /config from the auditor.
- *
- * @param cls auditor where to download /config from
- */
-static void
-request_version (void *cls)
-{
-  struct TALER_AUDITOR_Handle *auditor = cls;
-  CURL *eh;
-
-  auditor->retry_task = NULL;
-  GNUNET_assert (NULL == auditor->vr);
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Requesting auditor version with URL `%s'.\n",
-              auditor->vr_url);
-  eh = TALER_AUDITOR_curl_easy_get_ (auditor->vr_url);
-  if (NULL == eh)
-  {
-    GNUNET_break (0);
-    auditor->retry_delay = EXCHANGE_LIB_BACKOFF (auditor->retry_delay);
-    auditor->retry_task = GNUNET_SCHEDULER_add_delayed (auditor->retry_delay,
-                                                        &request_version,
-                                                        auditor);
-    return;
-  }
-  GNUNET_break (CURLE_OK ==
-                curl_easy_setopt (eh,
-                                  CURLOPT_TIMEOUT,
-                                  (long) 300));
-  auditor->vr = GNUNET_CURL_job_add (auditor->ctx,
-                                     eh,
-                                     &version_completed_cb,
-                                     auditor);
-}
-
-
-/* ********************* library internal API ********* */
-
-
-struct GNUNET_CURL_Context *
-TALER_AUDITOR_handle_to_context_ (struct TALER_AUDITOR_Handle *h)
-{
-  return h->ctx;
-}
-
-
-enum GNUNET_GenericReturnValue
-TALER_AUDITOR_handle_is_ready_ (struct TALER_AUDITOR_Handle *h)
-{
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Checking if auditor at `%s` is now ready: %s\n",
-              h->url,
-              (MHD_VERSION == h->state) ? "yes" : "no");
-  return (MHS_VERSION == h->state) ? GNUNET_YES : GNUNET_NO;
-}
-
-
-char *
-TALER_AUDITOR_path_to_url_ (struct TALER_AUDITOR_Handle *h,
-                            const char *path)
-{
-  GNUNET_assert ('/' == path[0]);
-  return TALER_url_join (h->url,
-                         path + 1,
-                         NULL);
-}
-
-
-/* ********************* public API ******************* */
-
-
-struct TALER_AUDITOR_Handle *
-TALER_AUDITOR_connect (struct GNUNET_CURL_Context *ctx,
-                       const char *url,
-                       TALER_AUDITOR_VersionCallback version_cb,
-                       void *version_cb_cls)
-{
-  struct TALER_AUDITOR_Handle *auditor;
-
-  auditor = GNUNET_new (struct TALER_AUDITOR_Handle);
-  auditor->version_cb = version_cb;
-  auditor->version_cb_cls = version_cb_cls;
-  auditor->retry_delay = GNUNET_TIME_UNIT_SECONDS; /* start slowly */
-  auditor->ctx = ctx;
-  auditor->url = GNUNET_strdup (url);
-  auditor->vr_url = TALER_AUDITOR_path_to_url_ (auditor,
-                                                "/config");
-  if (NULL == auditor->vr_url)
-  {
-    GNUNET_break (0);
-    GNUNET_free (auditor->url);
-    GNUNET_free (auditor);
-    return NULL;
-  }
-  auditor->retry_task = GNUNET_SCHEDULER_add_now (&request_version,
-                                                  auditor);
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Connecting to auditor at URL `%s'.\n",
-              url);
-  return auditor;
-}
-
-
-void
-TALER_AUDITOR_disconnect (struct TALER_AUDITOR_Handle *auditor)
-{
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Disconnecting from auditor at URL `%s'.\n",
-              auditor->url);
-  if (NULL != auditor->vr)
-  {
-    GNUNET_CURL_job_cancel (auditor->vr);
-    auditor->vr = NULL;
-  }
-  if (NULL != auditor->retry_task)
-  {
-    GNUNET_SCHEDULER_cancel (auditor->retry_task);
-    auditor->retry_task = NULL;
-  }
-  GNUNET_free (auditor->version);
-  GNUNET_free (auditor->vr_url);
-  GNUNET_free (auditor->url);
-  GNUNET_free (auditor);
-}
-
-
-/* end of auditor_api_handle.c */
diff --git a/src/lib/auditor_api_handle.h b/src/lib/auditor_api_handle.h
deleted file mode 100644
index 7ff5bfcdb..000000000
--- a/src/lib/auditor_api_handle.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2014, 2015 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 lib/auditor_api_handle.h
- * @brief Internal interface to the handle part of the auditor's HTTP API
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include <gnunet/gnunet_curl_lib.h>
-#include "taler_auditor_service.h"
-#include "taler_curl_lib.h"
-
-/**
- * Get the context of a auditor.
- *
- * @param h the auditor handle to query
- * @return ctx context to execute jobs in
- */
-struct GNUNET_CURL_Context *
-TALER_AUDITOR_handle_to_context_ (struct TALER_AUDITOR_Handle *h);
-
-
-/**
- * Check if the handle is ready to process requests.
- *
- * @param h the auditor handle to query
- * @return #GNUNET_YES if we are ready, #GNUNET_NO if not
- */
-int
-TALER_AUDITOR_handle_is_ready_ (struct TALER_AUDITOR_Handle *h);
-
-
-/**
- * Obtain the URL to use for an API request.
- *
- * @param h the auditor handle to query
- * @param path Taler API path (i.e. "/deposit-confirmation")
- * @return the full URL to use with cURL
- */
-char *
-TALER_AUDITOR_path_to_url_ (struct TALER_AUDITOR_Handle *h,
-                            const char *path);
-
-
-/* end of auditor_api_handle.h */
diff --git a/src/lib/exchange_api_handle.c b/src/lib/exchange_api_handle.c
index 0d9bf0416..4d245b077 100644
--- a/src/lib/exchange_api_handle.c
+++ b/src/lib/exchange_api_handle.c
@@ -110,7 +110,7 @@ struct TEAH_AuditorListEntry
   /**
    * Handle to the auditor.
    */
-  struct TALER_AUDITOR_Handle *ah;
+  struct TALER_AUDITOR_GetConfigHandle *ah;
 
   /**
    * Head of DLL of interactions with this auditor.
@@ -583,13 +583,14 @@ parse_global_fee (struct TALER_EXCHANGE_GlobalFee *gf,
  * @param vr response from the auditor
  */
 static void
-auditor_version_cb (
+auditor_config_cb (
   void *cls,
-  const struct TALER_AUDITOR_VersionResponse *vr)
+  const struct TALER_AUDITOR_ConfigResponse *vr)
 {
   struct TEAH_AuditorListEntry *ale = cls;
   enum TALER_AUDITOR_VersionCompatibility compat;
 
+  ale->ah = NULL;
   if (MHD_HTTP_OK != vr->hr.http_status)
   {
     /* In this case, we don't mark the auditor as 'up' */
@@ -664,10 +665,10 @@ update_auditors (struct TALER_EXCHANGE_Handle *exchange)
     GNUNET_CONTAINER_DLL_insert (exchange->auditors_head,
                                  exchange->auditors_tail,
                                  ale);
-    ale->ah = TALER_AUDITOR_connect (exchange->ctx,
-                                     ale->auditor_url,
-                                     &auditor_version_cb,
-                                     ale);
+    ale->ah = TALER_AUDITOR_get_config (exchange->ctx,
+                                        ale->auditor_url,
+                                        &auditor_config_cb,
+                                        ale);
   }
 }
 
@@ -2137,9 +2138,11 @@ TALER_EXCHANGE_disconnect (struct TALER_EXCHANGE_Handle *exchange)
     GNUNET_CONTAINER_DLL_remove (exchange->auditors_head,
                                  exchange->auditors_tail,
                                  ale);
-    TALER_LOG_DEBUG ("Disconnecting the auditor `%s'\n",
-                     ale->auditor_url);
-    TALER_AUDITOR_disconnect (ale->ah);
+    if (NULL != ale->ah)
+    {
+      TALER_AUDITOR_get_config_cancel (ale->ah);
+      ale->ah = NULL;
+    }
     GNUNET_free (ale->auditor_url);
     GNUNET_free (ale);
   }
diff --git a/src/testing/test_auditor_api_version.c b/src/testing/test_auditor_api_version.c
index 1b4f2b17d..dcd542ad8 100644
--- a/src/testing/test_auditor_api_version.c
+++ b/src/testing/test_auditor_api_version.c
@@ -41,7 +41,7 @@
  */
 #define CONFIG_FILE "test_auditor_api-rsa.conf"
 
-static struct TALER_AUDITOR_Handle *ah;
+static struct TALER_AUDITOR_GetConfigHandle *ah;
 
 static struct GNUNET_CURL_Context *ctx;
 
@@ -62,7 +62,11 @@ do_shutdown (void *cls)
     GNUNET_SCHEDULER_cancel (tt);
     tt = NULL;
   }
-  TALER_AUDITOR_disconnect (ah);
+  if (NULL != ah)
+  {
+    TALER_AUDITOR_get_config_cancel (ah);
+    ah = NULL;
+  }
   GNUNET_CURL_fini (ctx);
   GNUNET_CURL_gnunet_rc_destroy (rc);
 }
@@ -86,9 +90,10 @@ do_timeout (void *cls)
  */
 static void
 version_cb (void *cls,
-            const struct TALER_AUDITOR_VersionResponse *vr)
+            const struct TALER_AUDITOR_ConfigResponse *vr)
 {
   (void) cls;
+  ah = NULL;
   if ( (MHD_HTTP_OK == vr->hr.http_status) &&
        (TALER_AUDITOR_VC_MATCH == vr->details.ok.compat) )
     global_ret = 0;
@@ -113,10 +118,10 @@ run (void *cls)
   ctx = GNUNET_CURL_init (&GNUNET_CURL_gnunet_scheduler_reschedule,
                           &rc);
   rc = GNUNET_CURL_gnunet_rc_create (ctx);
-  ah = TALER_AUDITOR_connect (ctx,
-                              auditor_url,
-                              &version_cb,
-                              NULL);
+  ah = TALER_AUDITOR_get_config (ctx,
+                                 auditor_url,
+                                 &version_cb,
+                                 NULL);
   GNUNET_SCHEDULER_add_shutdown (&do_shutdown,
                                  NULL);
   tt = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
diff --git a/src/testing/testing_api_cmd_get_auditor.c b/src/testing/testing_api_cmd_get_auditor.c
index 2e9961c36..e1ae8ba54 100644
--- a/src/testing/testing_api_cmd_get_auditor.c
+++ b/src/testing/testing_api_cmd_get_auditor.c
@@ -49,9 +49,9 @@ struct GetAuditorState
   struct TALER_TESTING_Interpreter *is;
 
   /**
-   * Auditor handle we produced.
+   * Auditor handle used to get the configuration.
    */
-  struct TALER_AUDITOR_Handle *auditor;
+  struct TALER_AUDITOR_GetConfigHandle *auditor;
 
   /**
    * URL of the auditor.
@@ -75,16 +75,25 @@ struct GetAuditorState
 static void
 version_cb (
   void *cls,
-  const struct TALER_AUDITOR_VersionResponse *vr)
+  const struct TALER_AUDITOR_ConfigResponse *vr)
 {
   struct GetAuditorState *gas = cls;
 
+  gas->auditor = NULL;
   if (MHD_HTTP_OK != vr->hr.http_status)
   {
     TALER_TESTING_unexpected_status (gas->is,
                                      vr->hr.http_status);
     return;
   }
+  if ( (NULL != gas->priv_file) &&
+       (0 != GNUNET_memcmp (&gas->auditor_pub,
+                            &vr->details.ok.vi.auditor_pub)) )
+  {
+    GNUNET_break (0);
+    TALER_TESTING_interpreter_fail (gas->is);
+    return;
+  }
   TALER_TESTING_interpreter_next (gas->is);
 }
 
@@ -126,10 +135,10 @@ get_auditor_run (void *cls,
   }
   gas->is = is;
   gas->auditor
-    = TALER_AUDITOR_connect (TALER_TESTING_interpreter_get_context (is),
-                             gas->auditor_url,
-                             &version_cb,
-                             gas);
+    = TALER_AUDITOR_get_config (TALER_TESTING_interpreter_get_context (is),
+                                gas->auditor_url,
+                                &version_cb,
+                                gas);
   if (NULL == gas->auditor)
   {
     GNUNET_break (0);
@@ -153,7 +162,8 @@ get_auditor_cleanup (void *cls,
 
   if (NULL != gas->auditor)
   {
-    TALER_AUDITOR_disconnect (gas->auditor);
+    GNUNET_break (0);
+    TALER_AUDITOR_get_config_cancel (gas->auditor);
     gas->auditor = NULL;
   }
   GNUNET_free (gas->priv_file);
@@ -182,7 +192,6 @@ get_auditor_traits (void *cls,
   struct TALER_TESTING_Trait traits[] = {
     TALER_TESTING_make_trait_auditor_priv (&gas->auditor_priv),
     TALER_TESTING_make_trait_auditor_pub (&gas->auditor_pub),
-    TALER_TESTING_make_trait_auditor (gas->auditor),
     TALER_TESTING_make_trait_auditor_url (gas->auditor_url),
     TALER_TESTING_trait_end ()
   };