Line data    Source code

       1             : /*
       2             :   This file is part of TALER
       3             :   Copyright (C) 2021 Taler Systems SA
       4             : 
       5             :   TALER is free software; you can redistribute it and/or modify it under the
       6             :   terms of the GNU Affero General Public License as published by the Free Software
       7             :   Foundation; either version 3, or (at your option) any later version.
       8             : 
       9             :   TALER is distributed in the hope that it will be useful, but WITHOUT ANY
      10             :   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
      11             :   A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
      12             :   You should have received a copy of the GNU Affero General Public License along with
      13             :   TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
      14             : */
      15             : /**
      16             :  * @file taler-exchange-httpd_extensions.c
      17             :  * @brief Handle extensions (age-restriction, peer2peer)
      18             :  * @author Özgür Kesim
      19             :  */
      20             : #include "platform.h"
      21             : #include <gnunet/gnunet_json_lib.h>
      22             : #include "taler_dbevents.h"
      23             : #include "taler-exchange-httpd_responses.h"
      24             : #include "taler-exchange-httpd_extensions.h"
      25             : #include "taler_json_lib.h"
      26             : #include "taler_mhd_lib.h"
      27             : #include "taler_extensions.h"
      28             : #include <jansson.h>
      29             : 
      30             : /**
      31             :  * Handler listening for extensions updates by other exchange
      32             :  * services.
      33             :  */
      34             : static struct GNUNET_DB_EventHandler *extensions_eh;
      35             : 
      36             : /**
      37             :  * Function called whenever another exchange process has updated
      38             :  * the extensions data in the database.
      39             :  *
      40             :  * @param cls NULL
      41             :  * @param extra type of the extension
      42             :  * @param extra_size number of bytes in @a extra
      43             :  */
      44             : static void
      45           0 : extension_update_event_cb (void *cls,
      46             :                            const void *extra,
      47             :                            size_t extra_size)
      48             : {
      49             :   (void) cls;
      50             :   uint32_t nbo_type;
      51             :   enum TALER_Extension_Type type;
      52             :   const struct TALER_Extension *extension;
      53             : 
      54           0 :   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
      55             :               "Received extensions update event\n");
      56             : 
      57           0 :   if (sizeof(nbo_type) != extra_size)
      58             :   {
      59           0 :     GNUNET_break (0);
      60           0 :     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
      61             :                 "Oops, incorrect size of extra for TALER_Extension_type\n");
      62           0 :     return;
      63             :   }
      64             : 
      65           0 :   GNUNET_assert (NULL != extra);
      66             : 
      67           0 :   nbo_type = *(uint32_t *) extra;
      68           0 :   type = (enum TALER_Extension_Type) ntohl (nbo_type);
      69             : 
      70             :   /* Get the corresponding extension */
      71           0 :   extension = TALER_extensions_get_by_type (type);
      72           0 :   if (NULL == extension)
      73             :   {
      74           0 :     GNUNET_break (0);
      75           0 :     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
      76             :                 "Oops, unknown extension type: %d\n", type);
      77           0 :     return;
      78             :   }
      79             : 
      80             :   // Get the config from the database as string
      81             :   {
      82           0 :     char *config_str = NULL;
      83             :     enum GNUNET_DB_QueryStatus qs;
      84             :     json_error_t err;
      85             :     json_t *config;
      86             :     enum GNUNET_GenericReturnValue ret;
      87             : 
      88           0 :     qs = TEH_plugin->get_extension_config (TEH_plugin->cls,
      89           0 :                                            extension->name,
      90             :                                            &config_str);
      91             : 
      92           0 :     if (qs < 0)
      93             :     {
      94           0 :       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
      95             :                   "Couldn't get extension config\n");
      96           0 :       GNUNET_break (0);
      97           0 :       return;
      98             :     }
      99             : 
     100             :     // No config found -> disable extension
     101           0 :     if (NULL == config_str)
     102             :     {
     103           0 :       extension->disable ((struct TALER_Extension *) extension);
     104           0 :       return;
     105             :     }
     106             : 
     107             :     // Parse the string as JSON
     108           0 :     config = json_loads (config_str, JSON_DECODE_ANY, &err);
     109           0 :     if (NULL == config)
     110             :     {
     111           0 :       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
     112             :                   "Failed to parse config for extension `%s' as JSON: %s (%s)\n",
     113             :                   extension->name,
     114             :                   err.text,
     115             :                   err.source);
     116           0 :       GNUNET_break (0);
     117           0 :       return;
     118             :     }
     119             : 
     120             :     // Call the parser for the extension
     121           0 :     ret = extension->load_json_config (
     122             :       (struct TALER_Extension *) extension,
     123             :       config);
     124             : 
     125           0 :     if (GNUNET_OK != ret)
     126             :     {
     127           0 :       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
     128             :                   "Couldn't parse configuration for extension %s from the database",
     129             :                   extension->name);
     130           0 :       GNUNET_break (0);
     131             :     }
     132             :   }
     133             : 
     134             :   /* Special case age restriction: Update global flag and mask  */
     135           0 :   if (TALER_Extension_AgeRestriction == type)
     136             :   {
     137           0 :     TEH_age_restriction_enabled =
     138           0 :       TALER_extensions_age_restriction_is_enabled ();
     139             :   }
     140             : }
     141             : 
     142             : 
     143             : enum GNUNET_GenericReturnValue
     144           0 : TEH_extensions_init ()
     145             : {
     146           0 :   GNUNET_assert (GNUNET_OK ==
     147             :                  TALER_extension_age_restriction_register ());
     148             : 
     149             :   /* Set the event handler for updates */
     150           0 :   struct GNUNET_DB_EventHeaderP ev = {
     151           0 :     .size = htons (sizeof (ev)),
     152           0 :     .type = htons (TALER_DBEVENT_EXCHANGE_EXTENSIONS_UPDATED),
     153             :   };
     154           0 :   extensions_eh = TEH_plugin->event_listen (TEH_plugin->cls,
     155           0 :                                             GNUNET_TIME_UNIT_FOREVER_REL,
     156             :                                             &ev,
     157             :                                             &extension_update_event_cb,
     158             :                                             NULL);
     159           0 :   if (NULL == extensions_eh)
     160             :   {
     161           0 :     GNUNET_break (0);
     162           0 :     return GNUNET_SYSERR;
     163             :   }
     164             : 
     165             :   /* FIXME #7270: shall we load the extensions from the config right away?
     166             :    * We do have to for now, as otherwise denominations with age restriction
     167             :    * will not have the age mask set right upon initial generation.
     168             :    */
     169           0 :   TALER_extensions_load_taler_config (TEH_cfg);
     170             : 
     171             :   /* Trigger the initial load of configuration from the db */
     172           0 :   for (const struct TALER_Extension *it = TALER_extensions_get_head ();
     173           0 :        NULL != it->next;
     174           0 :        it = it->next)
     175           0 :     extension_update_event_cb (NULL, &it->type, sizeof(it->type));
     176             : 
     177           0 :   return GNUNET_OK;
     178             : }
     179             : 
     180             : 
     181             : void
     182           0 : TEH_extensions_done ()
     183             : {
     184           0 :   if (NULL != extensions_eh)
     185             :   {
     186           0 :     TEH_plugin->event_listen_cancel (TEH_plugin->cls,
     187             :                                      extensions_eh);
     188           0 :     extensions_eh = NULL;
     189             :   }
     190           0 : }
     191             : 
     192             : 
     193             : /* end of taler-exchange-httpd_extensions.c */