path: root/src/identity/gnunet-service-identity.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, 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with GNUnet; see the file COPYING.  If not, write to the
  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  Boston, MA 02110-1301, USA.
 */

/**
 * @file identity/gnunet-service-identity.c
 * @brief identity management service
 * @author Christian Grothoff
 *
 * The purpose of this service is to manage private keys that
 * represent the various egos/pseudonyms/identities of a GNUnet user.
 *
 * Todo:
 * - auto-initialze default egos; maybe trigger default
 *   initializations (such as gnunet-gns-import.sh?)
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_constants.h"
#include "gnunet_protocols.h"
#include "gnunet_statistics_service.h"
#include "gnunet_identity_service.h"
#include "identity.h"


/**
 * Information we keep about each ego.
 */
struct Ego
{

  /**
   * We keep egos in a DLL.
   */
  struct Ego *next;

  /**
   * We keep egos in a DLL.
   */
  struct Ego *prev;

  /**
   * Private key of the ego.
   */
  struct GNUNET_CRYPTO_EcdsaPrivateKey *pk;

  /**
   * String identifier for the ego.
   */
  char *identifier;

};


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

/**
 * Handle to subsystem configuration which for each subsystem contains
 * the name of the default ego.
 */
static struct GNUNET_CONFIGURATION_Handle *subsystem_cfg;

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

/**
 * Notification context, simplifies client broadcasts.
 */
static struct GNUNET_NotificationContext *nc;

/**
 * Directory where we store the identities.
 */
static char *ego_directory;

/**
 * Configuration file name where subsystem information is kept.
 */
static char *subsystem_cfg_file;

/**
 * Head of DLL of all egos.
 */
static struct Ego *ego_head;

/**
 * Tail of DLL of all egos.
 */
static struct Ego *ego_tail;


/**
 * Get the name of the file we use to store a given ego.
 *
 * @param ego ego for which we need the filename
 * @return full filename for the given ego
 */
static char *
get_ego_filename (struct Ego *ego)
{
  char *filename;

  GNUNET_asprintf (&filename,
		   "%s%s%s",
		   ego_directory,
		   DIR_SEPARATOR_STR,
		   ego->identifier);
  return filename;
}

/**
 * Called whenever a client is disconnected.
 *
 * @param cls closure
 * @param client identification of the client
 * @param app_ctx @a client
 */
static void
client_disconnect_cb (void *cls,
                      struct GNUNET_SERVICE_Client *client,
                      void *app_ctx)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Client %p disconnected\n",
              client);
}


/**
 * Add a client to our list of active clients.
 *
 * @param cls NULL
 * @param client client to add
 * @param mq message queue for @a client
 * @return internal namestore client structure for this client
 */
static void *
client_connect_cb (void *cls,
                   struct GNUNET_SERVICE_Client *client,
                   struct GNUNET_MQ_Handle *mq)
{
  return client;
}

/**
 * Task run during shutdown.
 *
 * @param cls unused
 */
static void
shutdown_task (void *cls)
{
  struct Ego *e;

  if (NULL != nc)
  {
    GNUNET_notification_context_destroy (nc);
    nc = NULL;
  }
  if (NULL != stats)
  {
    GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
    stats = NULL;
  }
  GNUNET_CONFIGURATION_destroy (subsystem_cfg);
  subsystem_cfg = NULL;
  GNUNET_free (subsystem_cfg_file);
  subsystem_cfg_file = NULL;
  GNUNET_free (ego_directory);
  ego_directory = NULL;
  while (NULL != (e = ego_head))
  {
    GNUNET_CONTAINER_DLL_remove (ego_head, ego_tail, e);
    GNUNET_free (e->pk);
    GNUNET_free (e->identifier);
    GNUNET_free (e);
  }
}


/**
 * Send a result code back to the client.
 *
 * @param client client that should receive the result code
 * @param result_code code to transmit
 * @param emsg error message to include (or NULL for none)
 */
static void
send_result_code (struct GNUNET_SERVICE_Client *client,
		  uint32_t result_code,
		  const char *emsg)
{
  struct ResultCodeMessage *rcm;
  struct GNUNET_MQ_Envelope *env;
  size_t elen;

  if (NULL == emsg)
    elen = 0;
  else
    elen = strlen (emsg) + 1;
  env = GNUNET_MQ_msg_extra (rcm,
                             elen,
                             GNUNET_MESSAGE_TYPE_IDENTITY_RESULT_CODE);
  rcm->result_code = htonl (result_code);
  if (0 < elen)
    GNUNET_memcpy (&rcm[1], emsg, elen);
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,