exchange

taler-exchange-httpd_management_extensions.c (8903B)

---

 /*
    This file is part of TALER
    Copyright (C) 2021 Taler Systems SA
 
    TALER is free software; you can redistribute it and/or modify it under the
    terms of the GNU Affero General Public License as published by the Free Software
    Foundation; either version 3, or (at your option) any later version.
 
    TALER is distributed in the hope that it will be useful, but WITHOUT ANY
    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
    A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
 
    You should have received a copy of the GNU Affero General Public License along with
    TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
  */
 /**
  * @file taler-exchange-httpd_management_extensions.c
  * @brief Handle request to POST /management/extensions
  * @author Özgür Kesim
  */
 #include "taler/platform.h"
 #include <gnunet/gnunet_util_lib.h>
 #include <gnunet/gnunet_json_lib.h>
 #include <jansson.h>
 #include <microhttpd.h>
 #include "taler/taler_json_lib.h"
 #include "taler/taler_mhd_lib.h"
 #include "taler/taler_signatures.h"
 #include "taler-exchange-httpd_management.h"
 #include "taler-exchange-httpd_responses.h"
 #include "taler/taler_extensions.h"
 #include "taler/taler_dbevents.h"
 
 /**
  * Extension carries the necessary data for a particular extension.
  *
  */
 struct Extension
 {
   enum TALER_Extension_Type type;
   json_t *manifest;
 };
 
 /**
  * Closure for the #set_extensions transaction
  */
 struct SetExtensionsContext
 {
   uint32_t num_extensions;
   struct Extension *extensions;
   struct TALER_MasterSignatureP extensions_sig;
 };
 
 /**
  * Function implementing database transaction to set the manifests of
  * extensions.  It runs the transaction logic.
  *  - IF it returns a non-error code, the transaction logic MUST NOT queue a
  *    MHD response.
  *  - IF it returns an hard error, the transaction logic MUST queue a MHD
  *    response and set @a mhd_ret.
  *  - IF it returns the soft error code, the function MAY be called again to
  *    retry and MUST not queue a MHD response.
  *
  * @param cls closure with a `struct SetExtensionsContext`
  * @param connection MHD request which triggered the transaction
  * @param[out] mhd_ret set to MHD response status for @a connection,
  *             if transaction failed (!)
  * @return transaction status
  */
 static enum GNUNET_DB_QueryStatus
 set_extensions (void *cls,
                 struct MHD_Connection *connection,
                 MHD_RESULT *mhd_ret)
 {
   struct SetExtensionsContext *sec = cls;
 
   /* save the manifests of all extensions */
   for (uint32_t i = 0; i<sec->num_extensions; i++)
   {
     struct Extension *ext = &sec->extensions[i];
     const struct TALER_Extension *taler_ext;
     enum GNUNET_DB_QueryStatus qs;
     char *manifest;
 
     taler_ext = TALER_extensions_get_by_type (ext->type);
     if (NULL == taler_ext)
     {
       /* No such extension found */
       GNUNET_break (0);
       return GNUNET_DB_STATUS_HARD_ERROR;
     }
 
     manifest = json_dumps (ext->manifest, JSON_COMPACT | JSON_SORT_KEYS);
     if (NULL == manifest)
     {
       GNUNET_break (0);
       *mhd_ret = TALER_MHD_reply_with_error (connection,
                                              MHD_HTTP_INTERNAL_SERVER_ERROR,
                                              TALER_EC_GENERIC_JSON_INVALID,
                                              "convert configuration to string");
       return GNUNET_DB_STATUS_HARD_ERROR;
     }
 
     qs = TEH_plugin->set_extension_manifest (
       TEH_plugin->cls,
       taler_ext->name,
       manifest);
 
     free (manifest);
 
     if (qs < 0)
     {
       if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
         return qs;
       GNUNET_break (0);
       *mhd_ret = TALER_MHD_reply_with_error (connection,
                                              MHD_HTTP_INTERNAL_SERVER_ERROR,
                                              TALER_EC_GENERIC_DB_STORE_FAILED,
                                              "save extension configuration");
     }
 
     /* Success, trigger event */
     {
       uint32_t nbo_type = htonl (sec->extensions[i].type);
       struct GNUNET_DB_EventHeaderP ev = {
         .size = htons (sizeof (ev)),
         .type = htons (TALER_DBEVENT_EXCHANGE_EXTENSIONS_UPDATED)
       };
 
       TEH_plugin->event_notify (TEH_plugin->cls,
                                 &ev,
                                 &nbo_type,
                                 sizeof(nbo_type));
     }
 
   }
 
   /* All extensions configured, update the signature */
   TEH_extensions_sig = sec->extensions_sig;
   TEH_extensions_signed = true;
 
   return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT; /* only 'success', so >=0, matters here */
 }
 
 
 static enum GNUNET_GenericReturnValue
 verify_extensions_from_json (
   const json_t *extensions,
   struct SetExtensionsContext *sec)
 {
   const char*name;
   const struct TALER_Extension *extension;
   size_t i = 0;
   json_t *manifest;
 
   GNUNET_assert (NULL != extensions);
   GNUNET_assert (json_is_object (extensions));
 
   sec->num_extensions = json_object_size (extensions);
   sec->extensions = GNUNET_new_array (sec->num_extensions,
                                       struct Extension);
 
   json_object_foreach ((json_t *) extensions, name, manifest)
   {
     int critical = 0;
     json_t *config;
     const char *version = NULL;
 
     /* load and verify criticality, version, etc. */
     extension = TALER_extensions_get_by_name (name);
     if (NULL == extension)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                   "no such extension: %s\n", name);
       return GNUNET_SYSERR;
     }
 
     if (GNUNET_OK !=
         TALER_extensions_parse_manifest (
           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->load_config (config, NULL))
       return GNUNET_SYSERR;
 
     sec->extensions[i].type = extension->type;
     sec->extensions[i].manifest = json_copy (manifest);
   }
 
   return GNUNET_OK;
 }
 
 
 MHD_RESULT
 TEH_handler_management_post_extensions (
   struct MHD_Connection *connection,
   const json_t *root)
 {
   MHD_RESULT ret;
   const json_t *extensions;
   struct SetExtensionsContext sec = {0};
   struct GNUNET_JSON_Specification top_spec[] = {
     GNUNET_JSON_spec_object_const ("extensions",
                                    &extensions),
     GNUNET_JSON_spec_fixed_auto ("extensions_sig",
                                  &sec.extensions_sig),
     GNUNET_JSON_spec_end ()
   };
 
   /* Parse the top level json structure */
   {
     enum GNUNET_GenericReturnValue res;
 
     res = TALER_MHD_parse_json_data (connection,
                                      root,
                                      top_spec);
     if (GNUNET_SYSERR == res)
       return MHD_NO; /* hard failure */
     if (GNUNET_NO == res)
       return MHD_YES; /* failure */
   }
 
   /* Verify the signature */
   {
     struct TALER_ExtensionManifestsHashP h_manifests;
 
     if (GNUNET_OK !=
         TALER_JSON_extensions_manifests_hash (extensions,
                                               &h_manifests) ||
         GNUNET_OK !=
         TALER_exchange_offline_extension_manifests_hash_verify (
           &h_manifests,
           &TEH_master_public_key,
           &sec.extensions_sig))
     {
       return TALER_MHD_reply_with_error (
         connection,
         MHD_HTTP_BAD_REQUEST,
         TALER_EC_GENERIC_PARAMETER_MALFORMED,
         "invalid signuture");
     }
   }
 
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Received /management/extensions\n");
 
   /* Now parse individual extensions and signatures from those objects. */
   if (GNUNET_OK !=
       verify_extensions_from_json (extensions, &sec))
   {
     return TALER_MHD_reply_with_error (
       connection,
       MHD_HTTP_BAD_REQUEST,
       TALER_EC_GENERIC_PARAMETER_MALFORMED,
       "invalid object");
   }
 
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Received %u extensions\n",
               sec.num_extensions);
 
   /* now run the transaction to persist the configurations */
   {
     enum GNUNET_GenericReturnValue res;
 
     res = TEH_DB_run_transaction (connection,
                                   "set extensions",
                                   TEH_MT_REQUEST_OTHER,
                                   &ret,
                                   &set_extensions,
                                   &sec);
 
     if (GNUNET_SYSERR == res)
       goto CLEANUP;
   }
 
   ret = TALER_MHD_reply_static (
     connection,
     MHD_HTTP_NO_CONTENT,
     NULL,
     NULL,
     0);
 
 CLEANUP:
   for (unsigned int i = 0; i < sec.num_extensions; i++)
   {
     if (NULL != sec.extensions[i].manifest)
     {
       json_decref (sec.extensions[i].manifest);
     }
   }
   GNUNET_free (sec.extensions);
   return ret;
 }
 
 
 /* end of taler-exchange-httpd_management_management_post_extensions.c */