refactor extensions: config -> manifest

configure.ac

@@ -533,7 +533,7 @@ AC_CONFIG_FILES([Makefile
                  src/exchange-tools/Makefile
                  src/extensions/Makefile
                  src/extensions/age_restriction/Makefile
-                 src/extensions/policy_auction/Makefile
+                 src/extensions/policy_brandt_vickrey_auction/Makefile
                  src/lib/Makefile
                  src/kyclogic/Makefile
                  src/testing/Makefile

src/Makefile.am

@@ -32,7 +32,7 @@ SUBDIRS = \
   auditor \
   lib \
   exchange-tools \
-  extensions/policy_auction \
   extensions/age_restriction \
+  extensions/policy_brandt_vickrey_auction \
   testing \
   benchmark

src/exchange-tools/taler-exchange-offline.c

@@ -140,6 +140,7 @@ static const struct GNUNET_CONFIGURATION_Handle *kcfg;
 /**
  * Age restriction configuration
  */
+static bool ar_enabled = false;
 static struct TALER_AgeRestrictionConfig ar_config = {0};
 
 /**
@@ -2169,14 +2170,14 @@ upload_extensions (const char *exchange_url,
 
   /* 2. Verify the signature */
   {
-    struct TALER_ExtensionConfigHashP h_config;
+    struct TALER_ExtensionManifestsHashP h_manifests;
 
     if (GNUNET_OK !=
-        TALER_JSON_extensions_config_hash (extensions, &h_config))
+        TALER_JSON_extensions_manifests_hash (extensions, &h_manifests))
     {
       GNUNET_JSON_parse_free (spec);
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                  "couldn't hash extensions\n");
+                  "couldn't hash extensions' manifests\n");
       global_ret = EXIT_FAILURE;
       test_shutdown ();
       return;
@@ -2186,8 +2187,8 @@ upload_extensions (const char *exchange_url,
         load_offline_key (GNUNET_NO))
       return;
 
-    if (GNUNET_OK != TALER_exchange_offline_extension_config_hash_verify (
+    if (GNUNET_OK != TALER_exchange_offline_extension_manifests_hash_verify (
-          &h_config,
+          &h_manifests,
           &master_pub,
           &sig))
     {
@@ -3889,7 +3890,7 @@ load_age_mask (const char*section_name)
   static const struct TALER_AgeMask null_mask = {0};
   enum GNUNET_GenericReturnValue ret;
 
-  if (! ar_config.enabled)
+  if (! ar_enabled)
     return null_mask;
 
   if (GNUNET_OK != (GNUNET_CONFIGURATION_have_value (
@@ -4263,7 +4264,7 @@ do_extensions_show (char *const *args)
 
     ret = json_object_set_new (exts,
                                extension->name,
-                               extension->config_to_json (extension));
+                               extension->manifest (extension));
     GNUNET_assert (-1 != ret);
   }
 
@@ -4286,7 +4287,7 @@ static void
 do_extensions_sign (char *const *args)
 {
   json_t *extensions = json_object ();
-  struct TALER_ExtensionConfigHashP h_config;
+  struct TALER_ExtensionManifestsHashP h_manifests;
   struct TALER_MasterSignatureP sig;
   const struct TALER_Extensions *it;
   bool found = false;
@@ -4294,7 +4295,7 @@ do_extensions_sign (char *const *args)
 
   GNUNET_assert (NULL != extensions);
   for (it = TALER_extensions_get_head ();
-       NULL != it;
+       NULL != it && NULL != it->extension;
        it = it->next)
   {
     const struct TALER_Extension *ext = it->extension;
@@ -4305,16 +4306,15 @@ do_extensions_sign (char *const *args)
     GNUNET_assert (0 ==
                    json_object_set_new (extensions,
                                         ext->name,
-                                        ext->config_to_json (
+                                        ext->manifest (ext)));
-                                          ext)));
   }
 
   if (! found)
     return;
 
   if (GNUNET_OK !=
-      TALER_JSON_extensions_config_hash (extensions,
+      TALER_JSON_extensions_manifests_hash (extensions,
-                                         &h_config))
+                                            &h_manifests))
   {
     json_decref (extensions);
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
@@ -4329,7 +4329,7 @@ do_extensions_sign (char *const *args)
     return;
   }
 
-  TALER_exchange_offline_extension_config_hash_sign (&h_config,
+  TALER_exchange_offline_extension_manifests_hash_sign (&h_manifests,
                                                         &master_priv,
                                                         &sig);
   obj = GNUNET_JSON_PACK (
@@ -4339,6 +4339,10 @@ do_extensions_sign (char *const *args)
       "extensions_sig",
       &sig));
 
+  GNUNET_log(GNUNET_ERROR_TYPE_INFO,
+		  "DEBUG sending extensions object: '%s'\n",
+		  json_dumps(obj, JSON_INDENT(2)));
+
   output_operation (OP_EXTENSIONS,
                     obj);
   next (args);
@@ -4547,7 +4551,7 @@ run (void *cls,
 
   /* load extensions */
   GNUNET_assert (GNUNET_OK ==
-                 TALER_extensions_load (kcfg));
+                 TALER_extensions_init (kcfg));
 
   /* setup age restriction, if applicable */
   {
@@ -4557,7 +4561,7 @@ run (void *cls,
         (arc = TALER_extensions_get_age_restriction_config ()))
     {
       ar_config  = *arc;
-      ar_config.enabled = true;
+      ar_enabled = true;
     }
   }
 

src/exchange/taler-exchange-httpd.c

@@ -102,6 +102,7 @@ const struct GNUNET_CONFIGURATION_Handle *TEH_cfg;
  *
  * Set after loading the library, enabled in database event handler.
  */
+bool TEH_age_restriction_enabled = false;
 struct TALER_AgeRestrictionConfig TEH_age_restriction_config = {0};
 
 /**

src/exchange/taler-exchange-httpd.h

@@ -363,6 +363,7 @@ struct TEH_RequestHandler
 
 
 /* Age restriction configuration */
+extern bool TEH_age_restriction_enabled;
 extern struct TALER_AgeRestrictionConfig TEH_age_restriction_config;
 
 #endif

src/exchange/taler-exchange-httpd_batch-deposit.c

@@ -242,7 +242,7 @@ batch_deposit_transaction (void *cls,
                            MHD_RESULT *mhd_ret)
 {
   struct BatchDepositContext *dc = cls;
-  enum GNUNET_DB_QueryStatus qs;
+  enum GNUNET_DB_QueryStatus qs = GNUNET_OK;
   bool balance_ok;
   bool in_conflict;
 

src/exchange/taler-exchange-httpd_extensions.c

@@ -77,67 +77,66 @@ extension_update_event_cb (void *cls,
     return;
   }
 
-  // Get the config from the database as string
+  // Get the manifest from the database as string
-  if (extension->has_config)
   {
-    char *config_str = NULL;
+    char *manifest_str = NULL;
     enum GNUNET_DB_QueryStatus qs;
     json_error_t err;
-    json_t *config;
+    json_t *manifest_js;
     enum GNUNET_GenericReturnValue ret;
 
-    qs = TEH_plugin->get_extension_config (TEH_plugin->cls,
+    qs = TEH_plugin->get_extension_manifest (TEH_plugin->cls,
                                              extension->name,
-                                           &config_str);
+                                             &manifest_str);
 
     if (qs < 0)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                  "Couldn't get extension config\n");
+                  "Couldn't get extension manifest\n");
       GNUNET_break (0);
       return;
     }
 
     // No config found -> disable extension
-    if (NULL == config_str)
+    if (NULL == manifest_str)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                  "No configuration found for extension %s, disabling it\n",
+                  "No manifest found for extension %s, disabling it\n",
                   extension->name);
       extension->disable ((struct TALER_Extension *) extension);
       return;
     }
 
     // Parse the string as JSON
-    config = json_loads (config_str, JSON_DECODE_ANY, &err);
+    manifest_js = json_loads (manifest_str, JSON_DECODE_ANY, &err);
-    if (NULL == config)
+    if (NULL == manifest_js)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                  "Failed to parse config for extension `%s' as JSON: %s (%s)\n",
+                  "Failed to parse manifest for extension `%s' as JSON: %s (%s)\n",
                   extension->name,
                   err.text,
                   err.source);
       GNUNET_break (0);
-      free (config_str);
+      free (manifest_js);
       return;
     }
 
     // Call the parser for the extension
-    ret = extension->load_json_config (
+    ret = extension->load_config (
       (struct TALER_Extension *) extension,
-      json_object_get (config, "config"));
+      json_object_get (manifest_js, "config"));
 
     if (GNUNET_OK != ret)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                  "Couldn't parse configuration for extension %s from the database: %s\n",
+                  "Couldn't parse configuration for extension %s from the manifest in the database: %s\n",
                   extension->name,
-                  config_str);
+                  manifest_str);
       GNUNET_break (0);
     }
 
-    free (config_str);
+    free (manifest_str);
-    json_decref (config);
+    json_decref (manifest_js);
   }
 
   /* Special case age restriction: Update global flag and mask  */
@@ -145,11 +144,15 @@ extension_update_event_cb (void *cls,
   {
     const struct TALER_AgeRestrictionConfig *conf =
       TALER_extensions_get_age_restriction_config ();
+    TEH_age_restriction_enabled = false;
     if (NULL != conf)
+    {
+      TEH_age_restriction_enabled = true;
       TEH_age_restriction_config = *conf;
+    }
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
                 "[age restriction] DB event has changed the config to %s with mask: %s\n",
-                conf->enabled ? "enabled": "disabled",
+                TEH_age_restriction_enabled ? "enabled": "DISABLED",
                 TALER_age_mask_to_string (&conf->mask));
 
   }
@@ -167,13 +170,22 @@ TEH_extensions_init ()
 
   /* Load the shared libraries first */
   if (GNUNET_OK !=
-      TALER_extensions_load (TEH_cfg))
+      TALER_extensions_init (TEH_cfg))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "failed to load extensions");
     return GNUNET_SYSERR;
   }
 
+  /* Check for age restriction */
+  {
+    const struct TALER_AgeRestrictionConfig *arc;
+
+    if (NULL !=
+        (arc = TALER_extensions_get_age_restriction_config ()))
+      TEH_age_restriction_config = *arc;
+  }
+
   extensions_eh = TEH_plugin->event_listen (TEH_plugin->cls,
                                             GNUNET_TIME_UNIT_FOREVER_REL,
                                             &ev,
@@ -192,16 +204,16 @@ TEH_extensions_init ()
   {
     const struct TALER_Extension *ext = it->extension;
     uint32_t typ = htonl (ext->type);
-    char *conf = json_dumps (ext->config_to_json (ext), JSON_COMPACT);
+    char *manifest = json_dumps (ext->manifest (ext), JSON_COMPACT);
 
-    TEH_plugin->set_extension_config (TEH_plugin->cls,
+    TEH_plugin->set_extension_manifest (TEH_plugin->cls,
                                         ext->name,
-                                      conf);
+                                        manifest);
 
     extension_update_event_cb (NULL,
                                &typ,
                                sizeof(typ));
-    free (conf);
+    free (manifest);
   }
 
   return GNUNET_OK;

src/exchange/taler-exchange-httpd_keys.c

@@ -837,7 +837,7 @@ load_age_mask (const char*section_name)
 
   if (GNUNET_OK == ret)
   {
-    if (! TEH_age_restriction_config.enabled)
+    if (! TEH_age_restriction_enabled)
       GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                   "age restriction set in section %s, yet, age restriction is not enabled\n",
                   section_name);
@@ -1907,7 +1907,7 @@ create_krd (struct TEH_KeyStateHandle *ksh,
          iter = iter->next)
     {
       const struct TALER_Extension *extension = iter->extension;
-      json_t *ext;
+      json_t *manifest;
       int r;
 
       /* skip if not enabled */
@@ -1917,26 +1917,14 @@ create_krd (struct TEH_KeyStateHandle *ksh,
       /* flag our findings so far */
       has_extensions = true;
 
-      ext = GNUNET_JSON_PACK (
-        GNUNET_JSON_pack_bool ("critical",
-                               extension->critical),
-        GNUNET_JSON_pack_string ("version",
-                                 extension->version)
-        );
-      GNUNET_assert (NULL != ext);
 
-      if (extension->has_config)
+      manifest = extension->manifest(extension);
-      {
+      GNUNET_assert(manifest);
-        GNUNET_assert (extension->config_json);
-        json_object_set_new (ext,
-                             "config",
-                             extension->config_json);
-      }
 
       r = json_object_set_new (
         extensions,
         extension->name,
-        ext);
+        manifest);
       GNUNET_assert (0 == r);
     }
 

src/exchange/taler-exchange-httpd_management_extensions.c

@@ -80,7 +80,7 @@ set_extensions (void *cls,
     struct Extension *ext = &sec->extensions[i];
     const struct TALER_Extension *taler_ext;
     enum GNUNET_DB_QueryStatus qs;
-    char *config;
+    char *manifest;
 
     taler_ext = TALER_extensions_get_by_type (ext->type);
     if (NULL == taler_ext)
@@ -90,10 +90,8 @@ set_extensions (void *cls,
       return GNUNET_DB_STATUS_HARD_ERROR;
     }
 
-    GNUNET_assert (NULL != ext->config);
+    manifest = json_dumps (ext->config, JSON_COMPACT | JSON_SORT_KEYS);
-
+    if (NULL == manifest)
-    config = json_dumps (ext->config, JSON_COMPACT | JSON_SORT_KEYS);
-    if (NULL == config)
     {
       GNUNET_break (0);
       *mhd_ret = TALER_MHD_reply_with_error (connection,
@@ -103,12 +101,12 @@ set_extensions (void *cls,
       return GNUNET_DB_STATUS_HARD_ERROR;
     }
 
-    qs = TEH_plugin->set_extension_config (
+    qs = TEH_plugin->set_extension_manifest (
       TEH_plugin->cls,
       taler_ext->name,
-      config);
+      manifest);
 
-    free (config);
+    free (manifest);
 
     if (qs < 0)
     {
@@ -153,7 +151,7 @@ verify_extensions_from_json (
   const char*name;
   const struct TALER_Extension *extension;
   size_t i = 0;
-  json_t *blob;
+  json_t *manifest;
 
   GNUNET_assert (NULL != extensions);
   GNUNET_assert (json_is_object (extensions));
@@ -162,7 +160,7 @@ verify_extensions_from_json (
   sec->extensions = GNUNET_new_array (sec->num_extensions,
                                       struct Extension);
 
-  json_object_foreach (extensions, name, blob)
+  json_object_foreach (extensions, name, manifest)
   {
     int critical = 0;
     json_t *config;
@@ -178,14 +176,14 @@ verify_extensions_from_json (
     }
 
     if (GNUNET_OK !=
-        TALER_extensions_is_json_config (
+        TALER_extensions_parse_manifest (
-          blob, &critical, &version, &config))
+          manifest, &critical, &version, &config))
       return GNUNET_SYSERR;
 
     if (critical != extension->critical
         || 0 != strcmp (version, extension->version) // FIXME-oec: libtool compare
         || NULL == config
-        || GNUNET_OK != extension->test_json_config (config))
+        || GNUNET_OK != extension->load_config (NULL, config))
       return GNUNET_SYSERR;
 
     sec->extensions[i].type = extension->type;
@@ -226,7 +224,8 @@ TEH_handler_management_post_extensions (
   }
 
   /* Ensure we have an object */
-  if (! json_is_object (extensions))
+  if ((! json_is_object (extensions)) &&
+      (! json_is_null (extensions)))
   {
     GNUNET_JSON_parse_free (top_spec);
     return TALER_MHD_reply_with_error (
@@ -238,13 +237,13 @@ TEH_handler_management_post_extensions (
 
   /* Verify the signature */
   {
-    struct TALER_ExtensionConfigHashP h_config;
+    struct TALER_ExtensionManifestsHashP h_manifests;
 
     if (GNUNET_OK !=
-        TALER_JSON_extensions_config_hash (extensions, &h_config) ||
+        TALER_JSON_extensions_manifests_hash (extensions, &h_manifests) ||
         GNUNET_OK !=
-        TALER_exchange_offline_extension_config_hash_verify (
+        TALER_exchange_offline_extension_manifests_hash_verify (
-          &h_config,
+          &h_manifests,
           &TEH_master_public_key,
           &sec.extensions_sig))
     {

src/exchange/taler-exchange-httpd_refreshes_reveal.c

@@ -603,7 +603,7 @@ resolve_refreshes_reveal_denominations (
                         &rrc->coin_envelope_hash);
   }
 
-  if (TEH_age_restriction_config.enabled &&
+  if (TEH_age_restriction_enabled &&
       ((NULL == old_age_commitment_json) !=
        TALER_AgeCommitmentHash_isNullOrZero (
          &rctx->melt.session.coin.h_age_commitment)))
@@ -614,7 +614,7 @@ resolve_refreshes_reveal_denominations (
 
   /* Reconstruct the old age commitment and verify its hash matches the one
    * from the melt request */
-  if (TEH_age_restriction_config.enabled &&
+  if (TEH_age_restriction_enabled &&
       (NULL != old_age_commitment_json))
   {
     enum GNUNET_GenericReturnValue res;

src/exchangedb/plugin_exchangedb_postgres.c

@@ -3922,7 +3922,7 @@ prepare_statements (struct PostgresClosure *pg)
       "INSERT INTO extensions"
       "(extension_id"
       ",name"
-      ",config"
+      ",manifest"
       ") VALUES "
       "($1, $2, $3);",
       3),
@@ -4206,18 +4206,18 @@ prepare_statements (struct PostgresClosure *pg)
       "   AND start_row=$2"
       "   AND end_row=$3",
       3),
-    /* Used in #postgres_set_extension_config */
+    /* Used in #postgres_set_extension_manifest */
     GNUNET_PQ_make_prepare (
-      "set_extension_config",
+      "set_extension_manifest",
-      "INSERT INTO extensions (name, config) VALUES ($1, $2) "
+      "INSERT INTO extensions (name, manifest) VALUES ($1, $2) "
       "ON CONFLICT (name) "
-      "DO UPDATE SET config=$2",
+      "DO UPDATE SET manifest=$2",
       2),
-    /* Used in #postgres_get_extension_config */
+    /* Used in #postgres_get_extension_manifest */
     GNUNET_PQ_make_prepare (
-      "get_extension_config",
+      "get_extension_manifest",
       "SELECT "
-      " config "
+      " manifest "
       "FROM extensions"
       "   WHERE name=$1;",
       1),
@@ -15199,25 +15199,25 @@ postgres_delete_shard_locks (void *cls)
 
 
 /**
- * Function called to save the configuration of an extension
+ * Function called to save the manifest of an extension
- * (age-restriction, peer2peer, ...).  After successful storage of the
+ * (age_restriction, poliy_merchant_refund, ...).  After successful storage of
- * configuration it triggers the corresponding event.
+ * the manifest it triggers the corresponding event.
  *
  * @param cls the @e cls of this struct with the plugin-specific state
  * @param extension_name the name of the extension
- * @param config JSON object of the configuration as string
+ * @param manifest JSON object of the manifest as string
  * @return transaction status code
  */
 enum GNUNET_DB_QueryStatus
-postgres_set_extension_config (void *cls,
+postgres_set_extension_manifest (void *cls,
                                  const char *extension_name,
-                               const char *config)
+                                 const char *manifest)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_QueryParam pcfg =
-    (NULL == config || 0 == *config)
+    (NULL == manifest || 0 == *manifest)
     ? GNUNET_PQ_query_param_null ()
-    : GNUNET_PQ_query_param_string (config);
+    : GNUNET_PQ_query_param_string (manifest);
   struct GNUNET_PQ_QueryParam params[] = {
     GNUNET_PQ_query_param_string (extension_name),
     pcfg,
@@ -15225,24 +15225,24 @@ postgres_set_extension_config (void *cls,
   };
 
   return GNUNET_PQ_eval_prepared_non_select (pg->conn,
-                                             "set_extension_config",
+                                             "set_extension_manifest",
                                              params);
 }
 
 
 /**
- * Function called to get the configuration of an extension
+ * Function called to get the manifest of an extension
- * (age-restriction, peer2peer, ...)
+ * (age_restriction, policy_merchant_refund, ...)
  *
  * @param cls the @e cls of this struct with the plugin-specific state
  * @param extension_name the name of the extension
- * @param[out] config JSON object of the configuration as string
+ * @param[out] manifest Manifest of the extension encoded as JSON object
  * @return transaction status code
  */
 enum GNUNET_DB_QueryStatus
-postgres_get_extension_config (void *cls,
+postgres_get_extension_manifest (void *cls,
                                const char *extension_name,
-                               char **config)
+                               char **manifest)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_QueryParam params[] = {
@@ -15252,15 +15252,15 @@ postgres_get_extension_config (void *cls,
   bool is_null;
   struct GNUNET_PQ_ResultSpec rs[] = {
     GNUNET_PQ_result_spec_allow_null (
-      GNUNET_PQ_result_spec_string ("config",
+      GNUNET_PQ_result_spec_string ("manifest",
-                                    config),
+                                    manifest),
       &is_null),
     GNUNET_PQ_result_spec_end
   };
 
-  *config = NULL;
+  *manifest = NULL;
   return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
-                                                   "get_extension_config",
+                                                   "get_extension_manifest",
                                                    params,
                                                    rs);
 }
@@ -17231,10 +17231,10 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
     = &postgres_release_revolving_shard;
   plugin->delete_shard_locks
     = &postgres_delete_shard_locks;
-  plugin->set_extension_config
+  plugin->set_extension_manifest
-    = &postgres_set_extension_config;
+    = &postgres_set_extension_manifest;
-  plugin->get_extension_config
+  plugin->get_extension_manifest
-    = &postgres_get_extension_config;
+    = &postgres_get_extension_manifest;
   plugin->insert_partner
     = &postgres_insert_partner;
   plugin->insert_contract

src/exchangedb/test_exchangedb.c

@@ -112,53 +112,53 @@ mark_prepare_cb (void *cls,
  * Simple check that config retrieval and setting for extensions work
  */
 static enum GNUNET_GenericReturnValue
-test_extension_config (void)
+test_extension_manifest (void)
 {
-  char *config;
+  char *manifest;
 
   FAILIF (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS !=
-          plugin->get_extension_config (plugin->cls,
+          plugin->get_extension_manifest (plugin->cls,
                                           "fnord",
-                                        &config));
+                                          &manifest));
 
   FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->set_extension_config (plugin->cls,
+          plugin->set_extension_manifest (plugin->cls,
                                           "fnord",
                                           "bar"));
   FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->get_extension_config (plugin->cls,
+          plugin->get_extension_manifest (plugin->cls,
                                           "fnord",
-                                        &config));
+                                          &manifest));
 
-  FAILIF (0 != strcmp ("bar", config));
+  FAILIF (0 != strcmp ("bar", manifest));
-  GNUNET_free (config);
+  GNUNET_free (manifest);
 
   /* let's do this again! */
   FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->set_extension_config (plugin->cls,
+          plugin->set_extension_manifest (plugin->cls,
                                           "fnord",
                                           "buzz"));
 
   FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->get_extension_config (plugin->cls,
+          plugin->get_extension_manifest (plugin->cls,
                                           "fnord",
-                                        &config));
+                                          &manifest));
 
-  FAILIF (0 != strcmp ("buzz", config));
+  FAILIF (0 != strcmp ("buzz", manifest));
-  GNUNET_free (config);
+  GNUNET_free (manifest);
 
   /* let's do this again, with NULL */
   FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->set_extension_config (plugin->cls,
+          plugin->set_extension_manifest (plugin->cls,
                                           "fnord",
                                           NULL));
 
   FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->get_extension_config (plugin->cls,
+          plugin->get_extension_manifest (plugin->cls,
                                           "fnord",
-                                        &config));
+                                          &manifest));
 
-  FAILIF (NULL != config);
+  FAILIF (NULL != manifest);
 
   return GNUNET_OK;
 drop:
@@ -1272,7 +1272,7 @@ run (void *cls)
                                                  NULL));
   /* simple extension check */
   FAILIF (GNUNET_OK !=
-          test_extension_config ());
+          test_extension_manifest ());
 
   RND_BLK (&reserve_pub);
   GNUNET_assert (GNUNET_OK ==

src/extensions/age_restriction/Makefile.am

@@ -22,7 +22,7 @@ libtaler_extension_age_restriction_la_LDFLAGS = \
   -no-undefined
 
 libtaler_extension_age_restriction_la_SOURCES = \
-  extension_age_restriction.c
+  age_restriction.c
 
 libtaler_extension_age_restriction_la_LIBADD = \
   $(top_builddir)/src/json/libtalerjson.la \

src/extensions/age_restriction/age_restriction.c

@@ -14,7 +14,7 @@
    TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
  */
 /**
- * @file extension_age_restriction.c
+ * @file age_restriction.c
  * @brief Utility functions regarding age restriction
  * @author Özgür Kesim
  */
@@ -51,26 +51,19 @@ age_restriction_disable (
   ext->enabled = false;
   ext->config = NULL;
 
-  if (NULL != ext->config_json)
-  {
-    json_decref (ext->config_json);
-    ext->config_json = NULL;
-  }
-
-  AR_config.enabled = false;
   AR_config.mask.bits = 0;
   AR_config.num_groups = 0;
 }
 
 
 /**
- * @brief implements the TALER_Extension.load_json_config interface.
+ * @brief implements the TALER_Extension.load_config interface.
  *
  * @param ext if NULL, only tests the configuration
  * @param jconfig the configuration as json
  */
 static enum GNUNET_GenericReturnValue
-age_restriction_load_json_config (
+age_restriction_load_config (
   struct TALER_Extension *ext,
   json_t *jconfig)
 {
@@ -98,14 +91,8 @@ age_restriction_load_json_config (
     AR_config.num_groups = __builtin_popcount (mask.bits) - 1;
   }
 
-  AR_config.enabled = true;
   ext->config = &AR_config;
-
-  if (NULL != ext->config_json)
-    json_decref (ext->config_json);
-
   ext->enabled = true;
-  ext->config_json = json_copy (jconfig);
   json_decref (jconfig);
 
   GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
@@ -117,13 +104,13 @@ age_restriction_load_json_config (
 
 
 /**
- * @brief implements the TALER_Extension.config_to_json interface.
+ * @brief implements the TALER_Extension.manifest interface.
  *
  * @param ext if NULL, only tests the configuration
  * @return configuration as json_t* object, maybe NULL
  */
 static json_t *
-age_restriction_config_to_json (
+age_restriction_manifest (
   const struct TALER_Extension *ext)
 {
   char *mask_str;
@@ -131,13 +118,6 @@ age_restriction_config_to_json (
 
   GNUNET_assert (NULL != ext);
 
-  if (! ext->enabled)
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                "age restriction not enabled");
-    return json_null ();
-  }
-
   if (NULL == ext->config)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
@@ -145,11 +125,6 @@ age_restriction_config_to_json (
     return json_null ();
   }
 
-  if (NULL != ext->config_json)
-  {
-    return json_copy (ext->config_json);
-  }
-
   mask_str = TALER_age_mask_to_string (&AR_config.mask);
   conf = GNUNET_JSON_PACK (
     GNUNET_JSON_pack_string ("age_groups", mask_str)
@@ -165,36 +140,19 @@ age_restriction_config_to_json (
 }
 
 
-/**
- * @brief implements the TALER_Extension.test_json_config interface.
- *
- * @param config configuration as json_t* to test
- * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise.
- */
-static enum GNUNET_GenericReturnValue
-age_restriction_test_json_config (
-  const json_t *config)
-{
-  struct TALER_AgeMask mask = {0};
-
-  return TALER_JSON_parse_age_groups (config, &mask);
-}
-
-
 /* The extension for age restriction */
-struct TALER_Extension TE_extension_age_restriction = {
+struct TALER_Extension TE_age_restriction = {
   .type = TALER_Extension_AgeRestriction,
   .name = "age_restriction",
   .critical = false,
   .version = "1",
   .enabled = false, /* disabled per default */
-  .has_config = true, /* we need to store configuration */
   .config = NULL,
-  .config_json = NULL,
   .disable = &age_restriction_disable,
-  .test_json_config = &age_restriction_test_json_config,
+  .load_config = &age_restriction_load_config,
-  .load_json_config = &age_restriction_load_json_config,
+  .manifest = &age_restriction_manifest,
-  .config_to_json = &age_restriction_config_to_json,
+  .deposit_handler = NULL,
+  .http_get_handler = NULL,
   .http_post_handler = NULL,
 };
 
@@ -261,23 +219,20 @@ libtaler_extension_age_restriction_init (void *arg)
 
   AR_config.mask = mask;
   AR_config.num_groups = __builtin_popcount (mask.bits) - 1;   /* no underflow, first bit always set */
-  AR_config.enabled = true;
 
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "[age restriction] setting age mask to %s with #groups: %d\n",
               TALER_age_mask_to_string (&AR_config.mask),
               __builtin_popcount (AR_config.mask.bits) - 1);
 
-  TE_extension_age_restriction.config = &AR_config;
+  TE_age_restriction.config = &AR_config;
-  TE_extension_age_restriction.enabled = true;
 
-  /* Note: we do now have TE_age_restriction_config set, however
+  /* Note: we do now have TE_age_restriction_config set, however the extension
-   * ext->config_json is NOT set, i.e. the extension is not yet active! For
+   * is not yet enabled! For age restriction to become active, load_config must
-   * age restriction to become active, load_json_config must have been
+   * have been called. */
-   * called. */
 
   GNUNET_free (groups);
-  return &TE_extension_age_restriction;
+  return &TE_age_restriction;
 }
 
 
@@ -292,11 +247,10 @@ libtaler_extension_age_restriction_done (void *arg)
 {
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "[age restriction] disabling and unloading");
-  AR_config.enabled = 0;
   AR_config.mask.bits = 0;
   AR_config.num_groups = 0;
   return NULL;
 }
 
 
-/* end of extension_age_restriction.c */
+/* end of age_restriction.c */

src/extensions/age_restriction_helper.c

@@ -61,8 +61,7 @@ TALER_extensions_get_age_restriction_mask ()
   ext = TALER_extensions_get_by_type (TALER_Extension_AgeRestriction);
 
   if ((NULL == ext) ||
-      (NULL == ext->config) ||
+      (NULL == ext->config))
-      (! ext->enabled))
     return (struct TALER_AgeMask) {0}
   ;
 

src/extensions/extensions.c

@@ -46,9 +46,8 @@ add_extension (
       (NULL == extension->name) ||
       (NULL == extension->version) ||
       (NULL == extension->disable) ||
-      (NULL == extension->test_json_config) ||
+      (NULL == extension->load_config) ||
-      (NULL == extension->load_json_config) ||
+      (NULL == extension->manifest))
-      (NULL == extension->config_to_json))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "invalid extension\n");
@@ -138,20 +137,20 @@ TALER_extensions_get_by_name (
 
 
 enum GNUNET_GenericReturnValue
-TALER_extensions_verify_json_config_signature (
+TALER_extensions_verify_manifests_signature (
-  json_t *extensions,
+  json_t *manifests,
   struct TALER_MasterSignatureP *extensions_sig,
   struct TALER_MasterPublicKeyP *master_pub)
 {
-  struct TALER_ExtensionConfigHashP h_config;
+  struct TALER_ExtensionManifestsHashP h_manifests;
 
   if (GNUNET_OK !=
-      TALER_JSON_extensions_config_hash (extensions,
+      TALER_JSON_extensions_manifests_hash (manifests,
-                                         &h_config))
+                                            &h_manifests))
     return GNUNET_SYSERR;
   if (GNUNET_OK !=
-      TALER_exchange_offline_extension_config_hash_verify (
+      TALER_exchange_offline_extension_manifests_hash_verify (
-        &h_config,
+        &h_manifests,
         master_pub,
         extensions_sig))
     return GNUNET_NO;
@@ -240,7 +239,7 @@ configure_extension (
 static bool extensions_loaded = false;
 
 enum GNUNET_GenericReturnValue
-TALER_extensions_load (
+TALER_extensions_init (
   const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
   struct LoadConfClosure col = {
@@ -263,7 +262,7 @@ TALER_extensions_load (
 
 
 enum GNUNET_GenericReturnValue
-TALER_extensions_is_json_config (
+TALER_extensions_parse_manifest (
   json_t *obj,
   int *critical,
   const char **version,
@@ -296,22 +295,21 @@ TALER_extensions_is_json_config (
 
 
 enum GNUNET_GenericReturnValue
-TALER_extensions_load_json_config (
+TALER_extensions_load_manifests (
   json_t *extensions)
 {
   const char*name;
-  json_t *blob;
+  json_t *manifest;
 
   GNUNET_assert (NULL != extensions);
   GNUNET_assert (json_is_object (extensions));
 
-  json_object_foreach (extensions, name, blob)
+  json_object_foreach (extensions, name, manifest)
   {
     int critical;
     const char *version;
     json_t *config;
-    const struct TALER_Extension *extension =
+    struct TALER_Extension *extension =  (struct TALER_Extension *)TALER_extensions_get_by_name (name);
-      TALER_extensions_get_by_name (name);
 
     if (NULL == extension)
     {
@@ -322,21 +320,22 @@ TALER_extensions_load_json_config (
 
     /* load and verify criticality, version, etc. */
     if (GNUNET_OK !=
-        TALER_extensions_is_json_config (
+        TALER_extensions_parse_manifest (
-          blob, &critical, &version, &config))
+          manifest, &critical, &version, &config))
       return GNUNET_SYSERR;
 
     if (critical != extension->critical
         || 0 != strcmp (version, extension->version) // TODO: libtool compare?
         || NULL == config
-        || GNUNET_OK != extension->test_json_config (config))
+        || GNUNET_OK != extension->load_config (NULL, config))
       return GNUNET_SYSERR;
 
     /* This _should_ work now */
     if (GNUNET_OK !=
-        extension->load_json_config ((struct TALER_Extension *) extension,
+        extension->load_config ( extension, config))
-                                     config))
       return GNUNET_SYSERR;
+
+    extension->enabled = true;
   }
 
   /* make sure to disable all extensions that weren't mentioned in the json */

src/extensions/policy_brandt_vickrey_auction/Makefile.am

@@ -16,16 +16,16 @@ endif
 plugindir = $(libdir)/taler
 
 plugin_LTLIBRARIES = \
-  libtaler_extension_policy_auction.la
+  libtaler_extension_policy_brandt_vickrey_auction.la
 
-libtaler_extension_policy_auction_la_LDFLAGS = \
+libtaler_extension_policy_brandt_vickrey_auction_la_LDFLAGS = \
   -version-info 0:0:0 \
   -no-undefined
 
-libtaler_extension_policy_auction_la_SOURCES = \
+libtaler_extension_policy_brandt_vickrey_auction_la_SOURCES = \
-  policy_auction.c
+  policy_brandt_vickrey_auction.c
 
-libtaler_extension_policy_auction_la_LIBADD = \
+libtaler_extension_policy_brandt_vickrey_auction_la_LIBADD = \
   $(top_builddir)/src/json/libtalerjson.la \
   $(top_builddir)/src/util/libtalerutil.la \
   -lgnunetjson \

src/extensions/policy_brandt_vickrey_auction/policy_brandt_vickrey_auction.c

@@ -14,7 +14,7 @@
    TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
  */
 /**
- * @file policy_auction.c
+ * @file policy_brandt_vickery_auction.c
  * @brief Extension for replay of auctions of type Brandt
  * @author Özgür Kesim
  */
@@ -26,13 +26,26 @@
 #include "stdint.h"
 #include <microhttpd.h>
 
-#define POLICY_AUCTION "policy_auction"
+#define POLICY_AUCTION "policy_brandt_vickery_auction"
-#define LOG_PREFIX "[policy_auction] "
+#define LOG_PREFIX "[policy_brandt_vickery_auction] "
 #define MAX_RESULT_SIZE 10 * 1024
 
+/* (public) configuration of this extension */
+/* TODO: these fields need to be set in the init handler */
+static struct TALER_BrandtVickreyAuction BV_config = {
+  .max_bidders = 10,
+  .max_prices = 10,
+  .auction_fee = {
+    .value = 0,
+    .fraction = 0,
+    .currency = {'E', 'U', 'R', 0, 0, 0, 0, 0, 0, 0, 0, 0},
+  },
+};
+
 /* Path to the replay program. */
 static char *replay_program;
 
+
 /* supported currency */
 static char *currency;
 
@@ -123,45 +136,6 @@ json_error (json_t **output,
   return GNUNET_SYSERR;
 };
 
-/**
- * @brief returns an JSON with the result
- */
-#if 0
-static enum GNUNET_GenericReturnValue
-json_result (json_t **output,
-             const struct transcript *tr)
-{
-  json_t *results;
-
-  GNUNET_assert (NULL != tr);
-
-  *output = json_object ();
-  results = json_array ();
-  GNUNET_assert (*output);
-  GNUNET_assert (results);
-
-  for (size_t i = 0; i < tr->results_len; i++)
-  {
-    json_t *result = json_pack ("{s:i, s:s}",
-                                "bidder", tr->results[i].bidder,
-                                "price", tr->results[i].price);
-    GNUNET_assert (result);
-
-    GNUNET_assert (-1 !=
-                   json_array_append_new (results, result));
-  }
-
-  GNUNET_assert (-1 !=
-                 json_object_set_new (*output,
-                                      "winners",
-                                      results));
-
-  return GNUNET_OK;
-}
-
-
-#endif
-
 
 /*
  * @brief Parses a given json as transcript.
@@ -508,55 +482,49 @@ static void
 auction_disable (
   struct TALER_Extension *ext)
 {
-  /* TODO: cleanup configuration */
+  ext->config = NULL;
   ext->enabled = false;
 }
 
 
 /**
- * @brief implements the TALER_Extension.test_json_config interface.
+ * @brief implements the TALER_Extension.manifest interface.
- *
- * @param config configuration as json_t* to test
- * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise.
- */
-static enum GNUNET_GenericReturnValue
-auction_test_json_config (
-  const json_t *config)
-{
-  /* This extension has no configuration */
-  return GNUNET_OK;
-}
-
-
-/**
- * @brief implements the TALER_Extension.config_to_json interface.
  *
  * @param ext if NULL, only tests the configuration
  * @return configuration as json_t* object, maybe NULL
  */
 static json_t *
-auction_config_to_json (
+auction_manifest (
   const struct TALER_Extension *ext)
 {
-  /* TODO: add configuration */
+  struct TALER_BrandtVickreyAuction *conf = ext->config;
+  GNUNET_assert (conf);
+
+  json_t *config = GNUNET_JSON_PACK (
+    GNUNET_JSON_pack_int64 ("max_bidders", conf->max_bidders),
+    GNUNET_JSON_pack_int64 ("max_prices", conf->max_prices),
+    TALER_JSON_pack_amount ("auction_fee", &conf->auction_fee));
+  GNUNET_assert (config);
+
   return GNUNET_JSON_PACK (
     GNUNET_JSON_pack_bool ("critical", ext->critical),
-    GNUNET_JSON_pack_string ("version", ext->version));
+    GNUNET_JSON_pack_string ("version", ext->version),
+    GNUNET_JSON_pack_object_steal ("config", config));
 }
 
 
 /**
- * @brief implements the TALER_Extension.load_json_config interface.
+ * @brief implements the TALER_Extension.load_config interface.
  *
  * @param ext if NULL, only tests the configuration
  * @param jconfig the configuration as json
  */
 static enum GNUNET_GenericReturnValue
-auction_load_json_config (
+auction_load_config (
   struct TALER_Extension *ext,
   json_t *jconfig)
 {
-  /* TODO: add configuration */
+  /* TODO: parse configuration */
   ext->enabled = true;
   return GNUNET_OK;
 }
@@ -620,20 +588,36 @@ auction_http_post_handler (
 }
 
 
+/**
+ * @brief implements the TALER_Extensions.deposit_handler interface.
+ *
+ * @param[in] input JSON input from the client during a deposit request
+ * @param[out] output by this extension
+ * @return GNUNET_OK if the request was OK
+ */
+enum GNUNET_GenericReturnValue
+auction_deposit_handler (
+  json_t *input,
+  json_t **output)
+{
+  /* TODO */
+  *output = NULL;
+  return GNUNET_OK;
+}
+
+
 /* The extension struct for auctions of brandt-style */
 struct TALER_Extension TE_auction_brandt = {
-  .type = TALER_Extension_PolicyAuction,
+  .type = TALER_Extension_PolicyBrandtVickeryAuction,
   .name = POLICY_AUCTION,
   .critical = false,
   .version = "0",
   .enabled = false, /* disabled per default */
-  .has_config = true,
+  .config = &BV_config,
-  .config = NULL,
-  .config_json = NULL,
   .disable = &auction_disable,
-  .test_json_config = &auction_test_json_config,
+  .load_config = &auction_load_config,
-  .load_json_config = &auction_load_json_config,
+  .manifest = &auction_manifest,
-  .config_to_json = &auction_config_to_json,
+  .deposit_handler = &auction_deposit_handler,
   .http_get_handler = &auction_http_get_handler,
   .http_post_handler = &auction_http_post_handler,
 };
@@ -653,7 +637,7 @@ struct TALER_Extension TE_auction_brandt = {
  * @return Pointer to TE_auction_brandt
  */
 struct TALER_Extension *
-libtaler_extension_policy_auction_init (void *arg)
+libtaler_extension_policy_brandt_vickery_auction_init (void *arg)
 {
   const struct GNUNET_CONFIGURATION_Handle *cfg = arg;
 
@@ -705,7 +689,6 @@ libtaler_extension_policy_auction_init (void *arg)
 
   /* TODO: read other config parameters and generate configuration */
 
-
   return &TE_auction_brandt;
 }
 
@@ -718,7 +701,7 @@ libtaler_extension_policy_auction_init (void *arg)
  * @return null
  */
 void *
-libtaler_extension_policy_auction_done (void *arg)
+libtaler_extension_policy_brandt_vickery_auction_done (void *arg)
 {
   auction_disable (&TE_auction_brandt);
   GNUNET_free (replay_program);
@@ -728,4 +711,4 @@ libtaler_extension_policy_auction_done (void *arg)
 }
 
 
-/* end of policy_auction.c */
+/* end of policy_brandt_vickery_auction.c */

src/extensions/policy_escrow/TODO.md

@@ -0,0 +1,15 @@
+# Basic escrow extension
+
+- on deposit, coins can be put into escrow
+	- timeout will be specified
+	- target payto-URL
+	- public key for release
+	- returns escrow ID == hash of the coins.
+
+- /extension/escrow endpoint
+	- post request requires of escrow ID 
+	- signature of the release-key and all coins nedded
+	- transfere to target-payto-URL.
+
+- on timeout:
+	- coins are unblocked

src/include/taler_crypto_lib.h

@@ -727,10 +727,10 @@ struct TALER_PickupIdentifierP
 
 
 /**
- * @brief Salted hash over the JSON object representing the configuration of an
+ * @brief Salted hash over the JSON object representing the manifests of
- * extension.
+ * extensions.
  */
-struct TALER_ExtensionConfigHashP
+struct TALER_ExtensionManifestsHashP
 {
   /**
    * Actual hash value.
@@ -5242,31 +5242,31 @@ TALER_merchant_contract_sign (
 /* **************** /management/extensions offline signing **************** */
 
 /**
- * Create a signature for the hash of the configuration of an extension
+ * Create a signature for the hash of the manifests of extensionss
  *
- * @param h_config hash of the JSON object representing the configuration
+ * @param h_manifests hash of the JSON object representing the manifests
  * @param master_priv private key to sign with
  * @param[out] master_sig where to write the signature
  */
 void
-TALER_exchange_offline_extension_config_hash_sign (
+TALER_exchange_offline_extension_manifests_hash_sign (
-  const struct TALER_ExtensionConfigHashP *h_config,
+  const struct TALER_ExtensionManifestsHashP *h_manifests,
   const struct TALER_MasterPrivateKeyP *master_priv,
   struct TALER_MasterSignatureP *master_sig);
 
 
 /**
  * Verify the signature in @a master_sig of the given hash, taken over the JSON
- * blob representing the configuration of an extension
+ * blob representing the manifests of extensions
  *
- * @param h_config hash of the JSON blob of a configuration of an extension
+ * @param h_manifests hash of the JSON blob of a configuration of an extension
  * @param master_pub master public key of the exchange
  * @param master_sig signature of the exchange
  * @return #GNUNET_OK if signature is valid
  */
 enum GNUNET_GenericReturnValue
-TALER_exchange_offline_extension_config_hash_verify (
+TALER_exchange_offline_extension_manifests_hash_verify (
-  const struct TALER_ExtensionConfigHashP *h_config,
+  const struct TALER_ExtensionManifestsHashP *h_manifests,
   const struct TALER_MasterPublicKeyP *master_pub,
   const struct TALER_MasterSignatureP *master_sig
   );

src/include/taler_exchangedb_plugin.h

@@ -5175,23 +5175,23 @@ struct TALER_EXCHANGEDB_Plugin
 
 
   /**
-   * Function called to save the configuration of an extension
+   * Function called to save the manifest of an extension
-   * (age-restriction, peer2peer, ...)
+   * (age_restriction, policy_merchant_refund, ...)
    *
    * @param cls the @e cls of this struct with the plugin-specific state
    * @param extension_name the name of the extension
-   * @param config JSON object of the configuration as string, maybe NULL (== disabled extension)
+   * @param manifest Manifest of the extension encoded as JSON object, maybe NULL (== disabled extension)
    * @return transaction status code
    */
   enum GNUNET_DB_QueryStatus
-  (*set_extension_config)(void *cls,
+  (*set_extension_manifest)(void *cls,
                             const char *extension_name,
                             const char *config);
 
 
   /**
-   * Function called to retrieve the configuration of an extension
+   * Function called to retrieve the manifest of an extension
-   * (age-restriction, peer2peer, ...)
+   * (age_restriction, policy_merchant_refund, ...)
    *
    * @param cls the @e cls of this struct with the plugin-specific state
    * @param extension_name the name of the extension
@@ -5199,9 +5199,9 @@ struct TALER_EXCHANGEDB_Plugin
    * @return transaction status code
    */
   enum GNUNET_DB_QueryStatus
-  (*get_extension_config)(void *cls,
+  (*get_extension_manifest)(void *cls,
                             const char *extension_name,
-                          char **config);
+                            char **manifest);
 
 
   /**

src/include/taler_extensions.h

@@ -32,9 +32,9 @@
 enum TALER_Extension_Type
 {
   TALER_Extension_AgeRestriction             = 0,
-  TALER_Extension_PolicyRefund   = 1,
+  TALER_Extension_PolicyMerchantRefund       = 1,
-  TALER_Extension_PolicyAuction  = 2,
+  TALER_Extension_PolicyBrandtVickeryAuction = 2,
-  TALER_Extension_PolicyEscrow   = 3,
+  TALER_Extension_PolicyEscrowedPayment      = 3,
   TALER_Extension_MaxPredefined              = 4 // Must be last of the predefined
 };
 
@@ -52,42 +52,149 @@ struct TALER_Extensions
 /*
  * @brief Represents the implementation of an extension.
  *
- * TODO: add documentation
+ * An "Extension" is an optional feature for the Exchange.
+ * There are only two types of extensions:
+ *
+ * a) Age restriction:  This is a special feature that directly interacts with
+ * denominations and coins, but is not define policies during deposits, see b).
+ * The implementation of this extension doesn't have to implement any of the
+ * http- or depost-handlers in the struct.
+ *
+ * b) Policies for deposits:  These are extensions that define policies (such
+ * as refund, escrow or auctions) for deposit requests.  These extensions have
+ * to implement at least the deposit- and post-http-handler in the struct to be
+ * functional.
+ *
+ * In addition to the handlers defined in this struct, an extension must also
+ * be a plugin in the GNUNET_Plugin sense.  That is, it must implement the
+ * functions
+ *    1: (void *ext)libtaler_extension_<name>_init(void *cfg)
+ * and
+ *    2: (void *)libtaler_extension_<name>_done(void *)
+ *
+ * In 1:, the input will be the GNUNET_CONFIGURATION_Handle to the TALER
+ * configuration and the output must be the struct TALER_Extension * on
+ * success, NULL otherwise.
+ *
+ * In 2:, no arguments are passed and NULL is expected to be returned.
  */
 struct TALER_Extension
 {
+  /**
+   * Type of the extension.  Only one extension of a type can be loaded
+   * at any time.
+   */
   enum TALER_Extension_Type type;
-  char *name;
-  bool critical;
-  char *version;
-  void *config;
-  bool enabled;
-  bool has_config; /* some extension might not have a configuration */
-  json_t *config_json;
 
+  /**
+   * The name of the extension, must be unique among all loaded extensions.  It
+   * is used in URLs for /extension/$NAME as well.
+   */
+  char *name;
+
+  /**
+   * Criticality of the extension.  It has the same semantics as "critical" has
+   * for extensions in X.509:
+   * - if "true", the client must "understand" the extension before proceeding,
+   * - if "false", clients can safely skip extensions they do not understand.
+   * (see https://datatracker.ietf.org/doc/html/rfc5280#section-4.2)
+   */
+  bool critical;
+
+  /**
+   * Version of the extension must be provided in Taler's protocol verison ranges notation, see
+   * https://docs.taler.net/core/api-common.html#protocol-version-ranges
+   */
+  char *version;
+
+  /**
+   * If the extension is marked as enabled, it will be listed in the
+   * "extensions" field in the "/keys" response.
+   */
+  bool enabled;
+
+  /**
+   * Opaque (public) configuration object, set by the extension.
+   */
+  void *config;
+
+
+  /**
+   * @brief Handler to to disable the extension.
+   *
+   * @param ext The current extension object
+   */
   void (*disable)(struct TALER_Extension *ext);
 
-  enum GNUNET_GenericReturnValue (*test_json_config)(
+  /**
-    const json_t *config);
+   * @brief Handler to read an extension-specific configuration in JSON
-
+   * encoding and enable the extension.  Must be implemented by the extension.
-  enum GNUNET_GenericReturnValue (*load_json_config)(
+   *
+   * @param ext The extension object. If NULL, the configuration will only be checked.
+   * @param config A JSON blob
+   * @return GNUNET_OK if the json was a valid configuration for the extension.
+   */
+  enum GNUNET_GenericReturnValue (*load_config)(
     struct TALER_Extension *ext,
     json_t *config);
 
-  json_t *(*config_to_json)(
+  /**
+   * @brief Handler to return the manifest of the extension in JSON encoding.
+   *
+   * See
+   * https://docs.taler.net/design-documents/006-extensions.html#tsref-type-Extension
+   * for the definition.
+   *
+   * @param ext The extension object
+   * @return The JSON encoding of the extension, if enabled, NULL otherwise.
+   */
+  json_t *(*manifest)(
     const struct TALER_Extension *ext);
 
+  /**
+   * @brief Handler for /{batch}-deposit requests.  Can be NULL.
+   *
+   * When a deposit request refers to this extension in its policy
+   * (see https://docs.taler.net/core/api-exchange.html#deposit), this handler
+   * will be called during the deposit operation.
+   *
+   * @param[in] input The policy/extension specific data, provided by the client in
+   * the policy-field of the deposit request.
+   * @param[out] output Potential output by the extension to be provided to the
+   * client as part of the response to the deposit request.  Can be NULL.
+   * @return GNUNET_OK if the data was accepted by the extension.
+   */
+  enum GNUNET_GenericReturnValue (*deposit_handler)(
+    json_t *input,
+    json_t **output);
+
+  /**
+   * @brief Handler for POST-requests to the /policy/$name endpoint. Can be NULL.
+   *
+   * @param connection The current connection
+   * @param root The JSON body from the request
+   * @param args Additional query parameters of the request.
+   * @return MDH result
+   */
   MHD_RESULT (*http_post_handler)(
     struct MHD_Connection *connection,
     const json_t *root,
     const char *const args[]);
 
+  /**
+   * @brief Handler for GET-requests to the /policy/$name endpoint.  Can be NULL.
+   *
+   * @param connection The current connection
+   * @param root The JSON body from the request
+   * @param args Additional query parameters of the request.
+   * @return MDH result
+   */
   MHD_RESULT (*http_get_handler)(
     struct MHD_Connection *connection,
     const char *const args[]);
-
 };
 
+
 /**
  * Generic functions for extensions
  */
@@ -101,39 +208,38 @@ struct TALER_Extension
  *         or any particular configuration couldn't be parsed.
  */
 enum GNUNET_GenericReturnValue
-TALER_extensions_load (
+TALER_extensions_init (
   const struct GNUNET_CONFIGURATION_Handle *cfg);
 
 /*
- * @brief Checks the given obj to be a valid extension object and fill the
+ * @brief Parses a given JSON object as an extension manifest.
- * fields accordingly.
  *
- * @param[in] obj Object to verify is a valid extension
+ * @param[in] obj JSON object to parse as an extension manifest
  * @param{out] critical will be set to 1 if the extension is critical according to obj
  * @param[out] version will be set to the version of the extension according to obj
  * @param[out] config will be set to the configuration of the extension according to obj
  * @return OK on success, Error otherwise
  */
 enum GNUNET_GenericReturnValue
-TALER_extensions_is_json_config (
+TALER_extensions_parse_manifest (
   json_t *obj,
   int *critical,
   const char **version,
   json_t **config);
 
 /*
- * @brief Sets the configuration of the extensions from a given JSON object.
+ * @brief Loads extensions according to the manifests.
  *
- * The JSON object must be of type ExchangeKeysResponse as described in
+ * The JSON object must be of type ExtensionsManifestsResponse as described
- * https://docs.taler.net/design-documents/006-extensions.html#exchange
+ * in https://docs.taler.net/design-documents/006-extensions.html#exchange
  *
- * @param cfg JSON object containing the configuration for all extensions
+ * @param cfg JSON object containing the manifests for all extensions
  * @return #GNUNET_OK on success, #GNUNET_SYSERR if unknown extensions were
  *  found or any particular configuration couldn't be parsed.
  */
 enum GNUNET_GenericReturnValue
-TALER_extensions_load_json_config (
+TALER_extensions_load_manifests (
-  json_t *cfg);
+  json_t *manifests);
 
 /*
  * @brief Returns the head of the linked list of extensions.
@@ -186,7 +292,7 @@ TALER_extensions_is_enabled (
  * Verify the signature of a given JSON object for extensions with the master
  * key of the exchange.
  *
- * The JSON object must be of type ExchangeKeysResponse as described in
+ * The JSON object must be of type ExtensionsManifestsResponse as described in
  * https://docs.taler.net/design-documents/006-extensions.html#exchange
  *
  * @param extensions JSON object with the extension configuration
@@ -196,8 +302,8 @@ TALER_extensions_is_enabled (
  * and GNUNET_NO if the signature couldn't be verified.
  */
 enum GNUNET_GenericReturnValue
-TALER_extensions_verify_json_config_signature (
+TALER_extensions_verify_manifests_signature (
-  json_t *extensions,
+  json_t *manifests,
   struct TALER_MasterSignatureP *extensions_sig,
   struct TALER_MasterPublicKeyP *master_pub);
 
@@ -207,6 +313,8 @@ TALER_extensions_verify_json_config_signature (
  *
  * This extension is special insofar as it directly interacts with coins and
  * denominations.
+ *
+ * At the same time, it doesn't implement and http- or deposit-handlers.
  */
 
 #define TALER_EXTENSION_SECTION_AGE_RESTRICTION (TALER_EXTENSION_SECTION_PREFIX  \
@@ -228,7 +336,6 @@ TALER_extensions_verify_json_config_signature (
  */
 struct TALER_AgeRestrictionConfig
 {
-  bool enabled;
   struct TALER_AgeMask mask;
   uint8_t num_groups;
 };
@@ -260,7 +367,18 @@ TALER_extensions_get_age_restriction_mask ();
 
 
 /*
- * TODO: Add Peer2Peer Extension
+ * ================================
+ * Brandt-Vickrey Auctions
+ * ================================
  */
+/*
+ * @brief Configuration for Brandt-Vickrey auctions
+ */
+struct TALER_BrandtVickreyAuction
+{
+  uint16_t max_bidders;
+  uint16_t max_prices;
+  struct TALER_Amount auction_fee;
+};
 
 #endif

src/include/taler_json_lib.h

@@ -779,13 +779,13 @@ TALER_deposit_extension_hash (const json_t *extensions,
 /**
  * Hash the @a config of an extension, given as JSON
  *
- * @param config configuration of the extension
+ * @param manifests manifests of extensions
  * @param[out] eh where to write the extension hash
  * @return GNUNET_OK on success, GNUNET_SYSERR on failure
  */
 enum GNUNET_GenericReturnValue
-TALER_JSON_extensions_config_hash (const json_t *config,
+TALER_JSON_extensions_manifests_hash (const json_t *manifests,
-                                   struct TALER_ExtensionConfigHashP *eh);
+                                      struct TALER_ExtensionManifestsHashP *eh);
 
 /**
  * Canonicalize a JSON input to a string according to RFC 8785.

src/json/json.c

@@ -1037,10 +1037,10 @@ TALER_JSON_canonicalize (const json_t *input)
 
 
 enum GNUNET_GenericReturnValue
-TALER_JSON_extensions_config_hash (const json_t *config,
+TALER_JSON_extensions_manifests_hash (const json_t *manifests,
-                                   struct TALER_ExtensionConfigHashP *ech)
+                                      struct TALER_ExtensionManifestsHashP *ech)
 {
-  return dump_and_hash (config,
+  return dump_and_hash (manifests,
                         "taler-extension-configuration",
                         &ech->hash);
 }

src/lib/exchange_api_handle.c

@@ -897,18 +897,18 @@ decode_keys_json (const json_t *resp_obj,
     }
   }
 
-  /* Parse the supported extension(s): age-restriction. */
+  /* Parse the supported extension(s): age_restriction. */
   /* TODO: maybe lift all this into a FP in TALER_Extension ? */
   {
     struct TALER_MasterSignatureP extensions_sig = {0};
-    json_t *extensions = NULL;
+    json_t *manifests = NULL;
     bool no_extensions = false;
     bool no_signature = false;
 
     struct GNUNET_JSON_Specification ext_spec[] = {
       GNUNET_JSON_spec_mark_optional (
         GNUNET_JSON_spec_json ("extensions",
-                               &extensions),
+                               &manifests),
         &no_extensions),
       GNUNET_JSON_spec_mark_optional (
         GNUNET_JSON_spec_fixed_auto (
@@ -933,14 +933,14 @@ decode_keys_json (const json_t *resp_obj,
     {
       /* 2. We have an extensions object. Verify its signature. */
       EXITIF (GNUNET_OK !=
-              TALER_extensions_verify_json_config_signature (
+              TALER_extensions_verify_manifests_signature (
-                extensions,
+                manifests,
                 &extensions_sig,
                 &key_data->master_pub));
 
       /* 3. Parse and set the the configuration of the extensions accordingly */
       EXITIF (GNUNET_OK !=
-              TALER_extensions_load_json_config (extensions));
+              TALER_extensions_load_manifests (manifests));
     }
 
     /* 4. assuming we might have now a new value for age_mask, set it in key_data */

src/testing/test_exchange_auction.conf

@@ -93,9 +93,9 @@ HTTP_PORT = 9081
 #AGE_GROUPS = "8:10:12:14:16:18:21"
 
 # Enable policy of type auction for deposits.
-[exchange-extension-policy_auction]
+[exchange-extension-policy_brandt_vickrey_auction]
 ENABLED = YES
-REPLAY_PROGRAM = "/usr/local/bin/taler-exchange-auction_brandt-replay"
+REPLAY_PROGRAM = "/usr/local/bin/brandt_vickrey_auction-replay"
 
 # Sections starting with "coin_" specify which denominations
 # the exchange should support (and their respective fee structure)

src/testing/testing_api_helpers_exchange.c

@@ -315,7 +315,7 @@ sign_keys_for_exchange (void *cls,
   int ret;
 
   /* Load the extensions */
-  if (GNUNET_OK != TALER_extensions_load (cfg))
+  if (GNUNET_OK != TALER_extensions_init (cfg))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "couldn't load extensions");
@@ -716,7 +716,7 @@ TALER_TESTING_setup_with_exchange_cfg (
   int result;
 
   /* Load extensions */
-  if (GNUNET_OK != TALER_extensions_load (cfg))
+  if (GNUNET_OK != TALER_extensions_init (cfg))
     return GNUNET_SYSERR;
 
   if (GNUNET_OK !=

src/util/offline_signatures.c

@@ -942,7 +942,7 @@ GNUNET_NETWORK_STRUCT_BEGIN
  * @brief Signature made by the exchange offline key over the
  * configuration of an extension.
  */
-struct TALER_MasterExtensionConfigurationPS
+struct TALER_MasterExtensionManifestsPS
 {
   /**
    * Purpose is #TALER_SIGNATURE_MASTER_EXTENSION.   Signed
@@ -953,22 +953,22 @@ struct TALER_MasterExtensionConfigurationPS
   /**
    * Hash of the JSON object that represents the configuration of an extension.
    */
-  struct TALER_ExtensionConfigHashP h_config GNUNET_PACKED;
+  struct TALER_ExtensionManifestsHashP h_manifests GNUNET_PACKED;
 };
 
 GNUNET_NETWORK_STRUCT_END
 
 
 void
-TALER_exchange_offline_extension_config_hash_sign (
+TALER_exchange_offline_extension_manifests_hash_sign (
-  const struct TALER_ExtensionConfigHashP *h_config,
+  const struct TALER_ExtensionManifestsHashP *h_manifests,
   const struct TALER_MasterPrivateKeyP *master_priv,
   struct TALER_MasterSignatureP *master_sig)
 {
-  struct TALER_MasterExtensionConfigurationPS ec = {
+  struct TALER_MasterExtensionManifestsPS ec = {
     .purpose.purpose = htonl (TALER_SIGNATURE_MASTER_EXTENSION),
     .purpose.size = htonl (sizeof(ec)),
-    .h_config = *h_config
+    .h_manifests = *h_manifests
   };
   GNUNET_CRYPTO_eddsa_sign (&master_priv->eddsa_priv,
                             &ec,
@@ -977,16 +977,16 @@ TALER_exchange_offline_extension_config_hash_sign (
 
 
 enum GNUNET_GenericReturnValue
-TALER_exchange_offline_extension_config_hash_verify (
+TALER_exchange_offline_extension_manifests_hash_verify (
-  const struct TALER_ExtensionConfigHashP *h_config,
+  const struct TALER_ExtensionManifestsHashP *h_manifests,
   const struct TALER_MasterPublicKeyP *master_pub,
   const struct TALER_MasterSignatureP *master_sig
   )
 {
-  struct TALER_MasterExtensionConfigurationPS ec = {
+  struct TALER_MasterExtensionManifestsPS ec = {
     .purpose.purpose = htonl (TALER_SIGNATURE_MASTER_EXTENSION),
     .purpose.size = htonl (sizeof(ec)),
-    .h_config = *h_config
+    .h_manifests = *h_manifests
   };
 
   return GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MASTER_EXTENSION,