path: root/src/psycstore/gnunet-service-psycstore.c

/**
 * This file is part of GNUnet
 * Copyright (C) 2013 GNUnet e.V.
 *
 * GNUnet 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 of the License,
 * or (at your option) any later version.
 *
 * GNUnet 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.
 */

/**
 * @file psycstore/gnunet-service-psycstore.c
 * @brief PSYCstore service
 * @author Gabor X Toth
 * @author Christian Grothoff
 */

#include <inttypes.h>

#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_constants.h"
#include "gnunet_protocols.h"
#include "gnunet_statistics_service.h"
#include "gnunet_psyc_util_lib.h"
#include "gnunet_psycstore_service.h"
#include "gnunet_psycstore_plugin.h"
#include "psycstore.h"


/**
 * Handle to our current configuration.
 */
static const struct GNUNET_CONFIGURATION_Handle *cfg;

/**
 * Service handle.
 */
static struct GNUNET_SERVICE_Handle *service;

/**
 * Handle to the statistics service.
 */
static struct GNUNET_STATISTICS_Handle *stats;

/**
 * Database handle
 */
static struct GNUNET_PSYCSTORE_PluginFunctions *db;

/**
 * Name of the database plugin
 */
static char *db_lib_name;


/**
 * Task run during shutdown.
 *
 * @param cls unused
 */
static void
shutdown_task (void *cls)
{
  if (NULL != stats)
  {
    GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
    stats = NULL;
  }
  GNUNET_break (NULL == GNUNET_PLUGIN_unload (db_lib_name, db));
  GNUNET_free (db_lib_name);
  db_lib_name = NULL;
}


/**
 * Send a result code back to the client.
 *
 * @param client
 *        Client that should receive the result code.
 * @param result_code
 *        Code to transmit.
 * @param op_id
 *        Operation ID in network byte order.
 * @param err_msg
 *        Error message to include (or NULL for none).
 */
static void
send_result_code (struct GNUNET_SERVICE_Client *client,
                  uint64_t op_id,
                  int64_t result_code,
                  const char *err_msg)
{
  struct OperationResult *res;
  size_t err_size = 0;

  if (NULL != err_msg)
    err_size = strnlen (err_msg,
                        GNUNET_MAX_MESSAGE_SIZE - sizeof (*res) - 1) + 1;
  struct GNUNET_MQ_Envelope *
    env = GNUNET_MQ_msg_extra (res, err_size,
                               GNUNET_MESSAGE_TYPE_PSYCSTORE_RESULT_CODE);
  res->result_code = GNUNET_htonll (result_code - INT64_MIN);
  res->op_id = op_id;
  if (0 < err_size)
  {
    GNUNET_memcpy (&res[1], err_msg, err_size);
    ((char *) &res[1])[err_size - 1] = '\0';
  }

  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
	      "Sending result to client: %" PRId64 " (%s)\n",
	      result_code, err_msg);
  GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq (client), env);
}


enum
{
  MEMBERSHIP_TEST_NOT_NEEDED = 0,
  MEMBERSHIP_TEST_NEEDED = 1,
  MEMBERSHIP_TEST_DONE = 2,
} MessageMembershipTest;


struct SendClosure
{
  struct GNUNET_SERVICE_Client *client;

  /**
   * Channel's public key.
   */
  struct GNUNET_CRYPTO_EddsaPublicKey channel_key;

  /**
   * Slave's public key.
   */
  struct GNUNET_CRYPTO_EcdsaPublicKey slave_key;

  /**
   * Operation ID.
   */
  uint64_t op_id;

  /**
   * Membership test result.
   */
  int membership_test_result;

  /**
   * Do membership test with @a slave_key before returning fragment?
   * @see enum MessageMembershipTest
   */
  uint8_t membership_test;
};


static int
send_fragment (void *cls, struct GNUNET_MULTICAST_MessageHeader *msg,
               enum GNUNET_PSYCSTORE_MessageFlags flags)
{
  struct SendClosure *sc = cls;
  struct FragmentResult *res;

  if (MEMBERSHIP_TEST_NEEDED == sc->membership_test)
  {
    sc->membership_test = MEMBERSHIP_TEST_DONE;
    sc->membership_test_result
      = db->membership_test (db->cls, &sc->channel_key, &sc->slave_key,
                             GNUNET_ntohll (msg->message_id));
    switch (sc->membership_test_result)
    {
    case GNUNET_YES:
      break;

    case GNUNET_NO:
    case GNUNET_SYSERR:
      return GNUNET_NO;
    }
  }

  size_t msg_size = ntohs (msg->header.size);

  struct GNUNET_MQ_Envelope *
    env = GNUNET_MQ_msg_extra (res, msg_size,
                               GNUNET_MESSAGE_TYPE_PSYCSTORE_RESULT_FRAGMENT);
  res->op_id = sc->op_id;
  res->psycstore_flags = htonl (flags);
  GNUNET_memcpy