gnunet-secushare/src/social/gnunet-social.c

/*
     This file is part of GNUnet.
     Copyright (C) 2016 GNUnet e.V.

     GNUnet 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 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.
    
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
*/

/**
 * CLI tool to interact with the social service.
 *
 * @author Gabor X Toth
 */

#include <inttypes.h>

#include <gnunet/platform.h>
#include <gnunet/gnunet_util_lib.h>
#include "gnunet_social_service.h"

#define TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)

#define DATA2ARG(data) data, sizeof (data)

/* operations corresponding to API calls */

/** --status */
static int op_status;

/** --host-enter */
static int op_host_enter;

/** --host-reconnect */
static int op_host_reconnect;

/** --host-leave */
static int op_host_leave;

/** --host-announce */
static int op_host_announce;

/** --host-assign */
static int op_host_assign;

/** --guest-enter */
static int op_guest_enter;

/** --guest-reconnect */
static int op_guest_reconnect;

/** --guest-leave */
static int op_guest_leave;

/** --guest-talk */
static int op_guest_talk;

/** --replay */
static int op_replay;

/** --replay-latest */
static int op_replay_latest;

/** --look-at */
static int op_look_at;

/** --look-for */
static int op_look_for;


/* options */

/** --app */
static char *opt_app = "cli";

/** --place */
static char *opt_place;

/** --ego */
static char *opt_ego;

/** --gns */
static char *opt_gns;

/** --peer */
static char *opt_peer;

/** --follow */
static int opt_follow;

/** --welcome */
static int opt_welcome;

/** --deny */
static int opt_deny;

/** --method */
static char *opt_method;

/** --data */
// FIXME: should come from STDIN
static char *opt_data;

/** --name */
static char *opt_name;

/** --start */
static unsigned long long opt_start;

/** --until */
static unsigned long long opt_until;

/** --limit */
static unsigned long long opt_limit;


/* global vars */

/** exit code */
static int ret = 1;

/** are we waiting for service to close our connection */
static char is_disconnecting = 0;

/** Task handle for timeout termination. */
struct GNUNET_SCHEDULER_Task *timeout_task;

const struct GNUNET_CONFIGURATION_Handle *cfg;

struct GNUNET_PeerIdentity peer, this_peer;

struct GNUNET_SOCIAL_App *app;

/** public key of connected place */
struct GNUNET_CRYPTO_EddsaPublicKey place_pub_key;

struct GNUNET_PSYC_Slicer *slicer;

struct GNUNET_SOCIAL_Ego *ego;
struct GNUNET_CRYPTO_EcdsaPublicKey ego_pub_key;

struct GNUNET_SOCIAL_Host *hst;
struct GNUNET_SOCIAL_Guest *gst;
struct GNUNET_SOCIAL_Place *plc;

const char *method_received;


/* DISCONNECT */


/**
 * Callback called after the host or guest place disconnected.
 */
static void
disconnected (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "disconnected()\n");
  GNUNET_SCHEDULER_shutdown ();
}


/**
 * Callback called after the application disconnected.
 */
static void
app_disconnected (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "app_disconnected()\n");
  if (hst || gst)
  {
    if (hst)
    {
      GNUNET_SOCIAL_host_disconnect (hst, disconnected, NULL);
    }
    if (gst)
    {
      GNUNET_SOCIAL_guest_disconnect (gst, disconnected, NULL);
    }
  }
  else
  {
    GNUNET_SCHEDULER_shutdown ();
  }
}


/**
 * Disconnect from connected GNUnet services.
 */
static void
disconnect ()
{
  // handle that we get called several times from several places, but should we?
  if (!is_disconnecting++) {
    GNUNET_SOCIAL_app_disconnect (app, app_disconnected, NULL);
  }
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "disconnect() called for the #%d time\n", is_disconnecting);
}


static void
scheduler_shutdown (void *cls)
{
  disconnect ();
}


/**
 * Callback called when the program failed to finish the requested operation in time.
 */
static void
timeout (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "timeout()\n");
  disconnect ();
}

static void
schedule_success (void *cls)
{
  ret = 0;
  disconnect ();
}


static void
schedule_fail (void *cls)
{
  disconnect ();
}


/**
 * Schedule exit with success result.
 */
static void
exit_success ()
{
  if (timeout_task != NULL)
  {
    GNUNET_SCHEDULER_cancel (timeout_task);
    timeout_task = NULL;
  }
  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, schedule_success, NULL);
}


/**
 * Schedule exit with failure result.
 */
static void
exit_fail ()
{
  if (timeout_task != NULL)
  {
    GNUNET_SCHEDULER_cancel (timeout_task);
    timeout_task = NULL;
  }
  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, schedule_fail, NULL);
}


/* LEAVE */


/**
 * Callback notifying about the host has left and stopped hosting the place.
 *
 * This also indicates the end of the connection to the service.
 */
static void
host_left (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "The host has left the place.\n");
  exit_success ();
}


/**
 * Leave a place permanently and stop hosting a place.
 */
static void
host_leave ()
{
  GNUNET_SOCIAL_host_leave (hst, NULL, host_left, NULL);
  hst = NULL;
  plc = NULL;
}


/**
 * Callback notifying about the guest has left the place.
 *
 * This also indicates the end of the connection to the service.
 */
static void
guest_left (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Guest has left the place.\n");
}


/**
 * Leave a place permanently as guest.
 */
static void
guest_leave ()
{
  struct GNUNET_PSYC_Environment *env = GNUNET_PSYC_env_create ();
  // FIXME: wrong use of vars
  GNUNET_PSYC_env_add (env, GNUNET_PSYC_OP_SET,
                       "_message", DATA2ARG ("Leaving."));
  GNUNET_SOCIAL_guest_leave (gst, env, guest_left, NULL);
  GNUNET_PSYC_env_destroy (env);
  gst = NULL;
  plc = NULL;
}


/* ANNOUNCE / ASSIGN / TALK */


struct TransmitClosure
{
  const char *data;
  size_t size;
} tmit;


/**
 * Callback notifying about available buffer space to write message data
 * when transmitting messages using host_announce() or guest_talk()
 */
static int
notify_data (void *cls, uint16_t *data_size, void *data)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Transmit notify data: %u bytes available\n",
              *data_size);

  struct TransmitClosure *tmit = cls;
  uint16_t size = tmit->size < *data_size ? tmit->size : *data_size;
  *data_size = size;
  GNUNET_memcpy (data, tmit->data, size);

  tmit->size -= size;
  tmit->data += size;

  if (0 == tmit->size)
  {
    if ((op_host_announce || op_host_assign || op_guest_talk) && !opt_follow)
    {
      exit_success ();
    }
    return GNUNET_YES;
  }
  else
  {
    return GNUNET_NO;
  }
}


/**
 * Host announcement - send a message to the place.
 */
static void
host_announce (const char *method, const char *data, size_t data_size)
{
  struct GNUNET_PSYC_Environment *env = GNUNET_PSYC_env_create ();
  GNUNET_PSYC_env_add (env, GNUNET_PSYC_OP_SET,
                       "_foo", DATA2ARG ("bar baz"));

  tmit = (struct TransmitClosure) {};
  tmit.data = data;
  tmit.size = data_size;

  GNUNET_SOCIAL_host_announce (hst, method, env,
                               notify_data, &tmit,
                               GNUNET_SOCIAL_ANNOUNCE_NONE);
  GNUNET_PSYC_env_destroy (env);
}


/**
 * Assign a state var of @a name to the value of @a data.
 */
static void
host_assign (const char *name, const char *data, size_t data_size)
{
  struct GNUNET_PSYC_Environment *env = GNUNET_PSYC_env_create ();
  GNUNET_PSYC_env_add (env, GNUNET_PSYC_OP_ASSIGN,
                       name, data, data_size);

  tmit = (struct TransmitClosure) {};
  GNUNET_SOCIAL_host_announce (hst, "_assign", env,
                               notify_data, &tmit,
                               GNUNET_SOCIAL_ANNOUNCE_NONE);
  GNUNET_PSYC_env_destroy (env);
}


/**
 * Guest talk request to host.
 */
static void
guest_talk (const char *method,
            const char *data, size_t data_size)
{
  struct GNUNET_PSYC_Environment *env = GNUNET_PSYC_env_create ();
  GNUNET_PSYC_env_add (env, GNUNET_PSYC_OP_SET,
                       "_foo", DATA2ARG ("bar baz"));

  tmit = (struct TransmitClosure) {};
  tmit.data = data;
  tmit.size = data_size;

  GNUNET_SOCIAL_guest_talk (gst, method, env,
                            notify_data, &tmit,
                            GNUNET_SOCIAL_TALK_NONE);
  GNUNET_PSYC_env_destroy (env);
}


/* HISTORY REPLAY */


/**
 * Callback notifying about the end of history replay results.
 */
static void
recv_history_replay_result (void *cls, int64_t result,
                            const void *data, uint16_t data_size)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Received history replay result: %" PRId64 "\n"
              "%.*s\n",
              result, data_size, (const char *) data);

  if (op_replay || op_replay_latest)
  {
    exit_success ();
  }
}


/**
 * Replay history between a given @a start and @a end message IDs,
 * optionally filtered by a method @a prefix.
 */
static void
history_replay (uint64_t start, uint64_t end, const char *prefix)
{
  GNUNET_SOCIAL_place_history_replay (plc, start, end, prefix,
                                      GNUNET_PSYC_HISTORY_REPLAY_LOCAL,
                                      slicer,
                                      recv_history_replay_result,
                                      NULL);
}


/**
 * Replay latest @a limit messages.
 */
static void
history_replay_latest (uint64_t limit, const char *prefix)
{
  GNUNET_SOCIAL_place_history_replay_latest (plc, limit, prefix,
                                             GNUNET_PSYC_HISTORY_REPLAY_LOCAL,
                                             slicer,
                                             recv_history_replay_result,
                                             NULL);
}


/* LOOK AT/FOR */


/**
 * Callback notifying about the end of state var results.
 */
static void
look_result (void *cls, int64_t result_code,
             const void *data, uint16_t data_size)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Received look result: %" PRId64 "\n", result_code);

  if (op_look_at || op_look_for)
  {
    exit_success ();
  }
}


/**
 * Callback notifying about a state var result.
 */
static void
look_var (void *cls,
          const struct GNUNET_MessageHeader *mod,
          const char *name,
          const void *value,
          uint32_t value_size,
          uint32_t full_value_size)
{
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Received var: %s\n%.*s\n",
              name, value_size, (const char *) value);
}


/**
 * Look for a state var using exact match of the name.
 */
static void
look_at (const char *full_name)
{
  GNUNET_SOCIAL_place_look_at (plc, full_name, look_var, look_result, NULL);
}


/**
 * Look for state vars by name prefix.
 */
static void
look_for (const char *name_prefix)
{
  GNUNET_SOCIAL_place_look_for (plc, name_prefix, look_var, look_result, NULL);
}


/* SLICER */


/**
 * Callback notifying about the start of a new incoming message.
 */
static void
slicer_recv_method (void *cls,
                    const struct GNUNET_PSYC_MessageHeader *msg,
                    const struct GNUNET_PSYC_MessageMethod *meth,
                    uint64_t message_id,
                    const char *method_name)
{
  method_received = method_name;
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Received method for message ID %" PRIu64 ":\n"
              "%s (flags: %x)\n",
              message_id, method_name, ntohl (meth->flags));
  /* routing header is missing, so we just print double newline */
  printf("\n");
  /* we output . instead of | to indicate that this is not proper PSYC syntax */
  /* FIXME: use libpsyc here */
}


/**
 * Callback notifying about an incoming modifier.
 */
static void
slicer_recv_modifier (void *cls,
                      const struct GNUNET_PSYC_MessageHeader *msg,
                      const struct GNUNET_MessageHeader *pmsg,
                      uint64_t message_id,
                      enum GNUNET_PSYC_Operator oper,
                      const char *name,
                      const void *value,
                      uint16_t value_size,
                      uint16_t full_value_size)
{
#if 0
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Received modifier for message ID %" PRIu64 ":\n"
              "%c%s: %.*s (size: %u)\n",
              message_id, oper, name, value_size, (const char *) value, value_size);
#else
  /* obviously not binary safe */
  printf("%c%s\t%.*s\n",
              oper, name, value_size, (const char *) value);
#endif
}


/**
 * Callback notifying about an incoming data fragment.
 */
static void
slicer_recv_data (void *cls,
                  const struct GNUNET_PSYC_MessageHeader *msg,
                  const struct GNUNET_MessageHeader *pmsg,
                  uint64_t message_id,
                  const void *data,
                  uint16_t data_size)
{
#if 0
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Received data for message ID %" PRIu64 ":\n"
              "%.*s\n",
              message_id, data_size, (const char *) data);
#else
  /* obviously not binary safe */
  printf("%s\n%.*s\n",
              method_received, data_size, (const char *) data);
#endif
}


/**
 * Callback notifying about the end of a message.
 */
static void
slicer_recv_eom (void *cls,
                const struct GNUNET_PSYC_MessageHeader *msg,
                const struct GNUNET_MessageHeader *pmsg,
                uint64_t message_id,
                uint8_t is_cancelled)
{
  printf(".\n");
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Received end of message ID %" PRIu64
              ", cancelled: %u\n",
              message_id, is_cancelled);
}


/**
 * Create a slicer for receiving message parts.
 */
static struct GNUNET_PSYC_Slicer *
slicer_create ()
{
  slicer = GNUNET_PSYC_slicer_create ();

  /* register slicer to receive incoming messages with any method name */
  GNUNET_PSYC_slicer_method_add (slicer, "", NULL,
                                 slicer_recv_method, slicer_recv_modifier,
                                 slicer_recv_data, slicer_recv_eom, NULL);
  return slicer;
}


/* GUEST ENTER */


/**
 * Callback called when the guest receives an entry decision from the host.
 *
 * It is called once after using guest_enter() or guest_enter_by_name(),
 * in case of a reconnection only the local enter callback is called.
 */
static void
guest_recv_entry_decision (void *cls,
                           int is_admitted,
                           const struct GNUNET_PSYC_Message *entry_msg)
{
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Guest received entry decision %d\n",
              is_admitted);

  if (NULL != entry_msg)
  {
    struct GNUNET_PSYC_Environment *env = GNUNET_PSYC_env_create ();
    const char *method_name = NULL;
    const void *data = NULL;
    uint16_t data_size = 0;
    struct GNUNET_PSYC_MessageHeader *
      pmsg = GNUNET_PSYC_message_header_create_from_psyc (entry_msg);
    GNUNET_PSYC_message_parse (pmsg, &method_name, env, &data, &data_size);
    GNUNET_free (pmsg);

    GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
                "%s\n%.*s\n",
                method_name, data_size, (const char *) data);
  }

  if (op_guest_enter && !opt_follow)
  {
    exit_success ();
  }
}


/**
 * Callback called after a guest connection is established to the local service.
 */
static void
guest_recv_local_enter (void *cls, int result,
                        const struct GNUNET_CRYPTO_EddsaPublicKey *pub_key,
                        uint64_t max_message_id)
{
  char *pub_str = GNUNET_CRYPTO_eddsa_public_key_to_string (pub_key);
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Guest entered local place: %s, max_message_id: %" PRIu64 "\n",
              pub_str, max_message_id);
  GNUNET_free (pub_str);
  GNUNET_assert (0 <= result);

  if (op_guest_enter && !opt_follow)
  {
    exit_success ();
  }
}


/**
 * Create entry request message.
 */
static struct GNUNET_PSYC_Message *
guest_enter_msg_create ()
{
  const char *method_name = "_request_enter";
  struct GNUNET_PSYC_Environment *env = GNUNET_PSYC_env_create ();
  GNUNET_PSYC_env_add (env, GNUNET_PSYC_OP_SET,
                       "_foo", DATA2ARG ("bar"));
  void *data = "let me in";
  uint16_t data_size = strlen (data) + 1;

  return GNUNET_PSYC_message_create (method_name, env, data, data_size);
}


/**
 * Enter a place as guest, using its public key and peer ID.
 */
static void
guest_enter (const struct GNUNET_CRYPTO_EddsaPublicKey *pub_key,
             const struct GNUNET_PeerIdentity *peer)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Entering to place as guest.\n");

  if (NULL == ego)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "--ego missing or invalid\n");
    exit_fail ();
    return;
  }

  struct GNUNET_PSYC_Message *join_msg = guest_enter_msg_create ();
  gst = GNUNET_SOCIAL_guest_enter (app, ego, pub_key,
                                   GNUNET_PSYC_SLAVE_JOIN_NONE,
                                   peer, 0, NULL, join_msg, slicer_create (),
                                   guest_recv_local_enter,
                                   guest_recv_entry_decision, NULL);
  GNUNET_free (join_msg);
  plc = GNUNET_SOCIAL_guest_get_place (gst);
}


/**
 * Enter a place as guest using its GNS address.
 */
static void
guest_enter_by_name (const char *gns_name)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Entering to place by name as guest.\n");

  struct GNUNET_PSYC_Message *join_msg = guest_enter_msg_create ();
  gst = GNUNET_SOCIAL_guest_enter_by_name (app, ego, gns_name, NULL,
                                           join_msg, slicer,
                                           guest_recv_local_enter,
                                           guest_recv_entry_decision, NULL);
  GNUNET_free (join_msg);
  plc = GNUNET_SOCIAL_guest_get_place (gst);
}


/* HOST ENTER */


/**
 * Callback called when a @a nym wants to enter the place.
 *
 * The request needs to be replied with an entry decision.
 */
static void
host_answer_door (void *cls,
                  struct GNUNET_SOCIAL_Nym *nym,
                  const char *method_name,
                  struct GNUNET_PSYC_Environment *env,
                  const void *data,
                  size_t data_size)
{
  const struct GNUNET_CRYPTO_EcdsaPublicKey *
    nym_key = GNUNET_SOCIAL_nym_get_pub_key (nym);
  char *
    nym_str = GNUNET_CRYPTO_ecdsa_public_key_to_string (nym_key);

  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Entry request: %s\n", nym_str);
  GNUNET_free (nym_str);

  if (opt_welcome)
  {
    struct GNUNET_PSYC_Message *
      resp = GNUNET_PSYC_message_create ("_notice_place_admit", env,
                                         DATA2ARG ("Welcome, nym!"));
    GNUNET_SOCIAL_host_entry_decision (hst, nym, GNUNET_YES, resp);
    GNUNET_free (resp);
  }
  else if (opt_deny)
  {
    struct GNUNET_PSYC_Message *
      resp = GNUNET_PSYC_message_create ("_notice_place_refuse", NULL,
                                         DATA2ARG ("Go away!"));
    GNUNET_SOCIAL_host_entry_decision (hst, nym, GNUNET_NO, resp);
    GNUNET_free (resp);
  }


}


/**
 * Callback called when a @a nym has left the place.
 */
static void
host_farewell (void *cls,
               const struct GNUNET_SOCIAL_Nym *nym,
               struct GNUNET_PSYC_Environment *env)
{
  const struct GNUNET_CRYPTO_EcdsaPublicKey *
    nym_key = GNUNET_SOCIAL_nym_get_pub_key (nym);
  char *
    nym_str = GNUNET_CRYPTO_ecdsa_public_key_to_string (nym_key);

  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Farewell: %s\n", nym_str);
  GNUNET_free (nym_str);
}


/**
 * Callback called after the host entered the place.
 */
static void
host_entered (void *cls, int result,
              const struct GNUNET_CRYPTO_EddsaPublicKey *pub_key,
              uint64_t max_message_id)
{
  place_pub_key = *pub_key;
  char *pub_str = GNUNET_CRYPTO_eddsa_public_key_to_string (pub_key);
  GNUNET_log (GNUNET_ERROR_TYPE_MESSAGE,
              "Host entered: %s, max_message_id: %" PRIu64 "\n",
              pub_str, max_message_id);
  GNUNET_free (pub_str);

  if (op_host_enter && !opt_follow)
  {
    exit_success ();
  }
}


/**
 * Enter and start hosting a place.
 */
static void
host_enter ()
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "host_enter()\n");

  if (NULL == ego)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "--ego missing or invalid\n");
    exit_fail ();
    return;
  }

  hst = GNUNET_SOCIAL_host_enter (app, ego,
                                  GNUNET_PSYC_CHANNEL_PRIVATE,
                                  slicer_create (), host_entered,
                                  host_answer_door, host_farewell, NULL);
  plc = GNUNET_SOCIAL_host_get_place (hst);
}


/* PLACE RECONNECT */


/**
 * Perform operations common to both host & guest places.
 */
static void
place_reconnected ()
{
  static int first_run = GNUNET_YES;
  if (GNUNET_NO == first_run)
    return;
  first_run = GNUNET_NO;

  if (op_replay) {
    history_replay (opt_start, opt_until, opt_method);
  }
  else if (op_replay_latest) {
    history_replay_latest (opt_limit, opt_method);
  }
  else if (op_look_at) {
    look_at (opt_name);
  }
  else if (op_look_for) {
    look_for (opt_name);
  }
}


/**
 * Callback called after reconnecting to a host place.
 */
static void
host_reconnected (void *cls, int result,
		  const struct GNUNET_CRYPTO_EddsaPublicKey *place_pub_key,
		  uint64_t max_message_id)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Host reconnected.\n");

  if (op_host_leave) {
    host_leave ();
  }
  else if (op_host_announce) {
    host_announce (opt_method, opt_data, strlen (opt_data));
  }
  else if (op_host_assign) {
    host_assign (opt_name, opt_data, strlen (opt_data) + 1);
  }
  else {
    place_reconnected ();
  }
}


/**
 * Callback called after reconnecting to a guest place.
 */
static void
guest_reconnected (void *cls, int result,
                   const struct GNUNET_CRYPTO_EddsaPublicKey *place_pub_key,
                   uint64_t max_message_id)
{
  char *place_pub_str = GNUNET_CRYPTO_eddsa_public_key_to_string (place_pub_key);
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Guest reconnected to place %s.\n", place_pub_str);
  GNUNET_free (place_pub_str);

  if (op_guest_leave) {
    guest_leave ();
  }
  else if (op_guest_talk) {
    guest_talk (opt_method, opt_data, strlen (opt_data));
  }
  else {
    place_reconnected ();
  }
}


/* APP */


/**
 * Callback called after the ego and place callbacks.
 */
static void
app_connected (void *cls)
{
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "App connected: %p\n", cls);

  if (op_status)
  {
    exit_success ();
  }
  else if (op_host_enter)
  {
    host_enter ();
  }
  else if (op_guest_enter)
  {
    if (opt_gns)
    {
      guest_enter_by_name (opt_gns);
    }
    else
    {
      if (opt_peer)
      {
        if (GNUNET_OK != GNUNET_CRYPTO_eddsa_public_key_from_string (opt_peer,
                                                                     strlen (opt_peer),
                                                                     &peer.public_key))
        {
          GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                      "--peer invalid");
          exit_fail ();
          return;
        }
      }
      else
      {
        peer = this_peer;
      }
      guest_enter (&place_pub_key, &peer);
    }
  }
  printf(".\n");
}


/**
 * Callback notifying about a host place available for reconnection.
 */
static void
app_recv_host (void *cls,
               struct GNUNET_SOCIAL_HostConnection *hconn,
               struct GNUNET_SOCIAL_Ego *ego,
               const struct GNUNET_CRYPTO_EddsaPublicKey *host_pub_key,
               enum GNUNET_SOCIAL_AppPlaceState place_state)
{
  char *host_pub_str = GNUNET_CRYPTO_eddsa_public_key_to_string (host_pub_key);
  printf ("Host\t%s\n", host_pub_str);
  GNUNET_free (host_pub_str);

  if ((op_host_reconnect || op_host_leave || op_host_announce || op_host_assign
       || op_replay || op_replay_latest
       || op_look_at || op_look_for)
      && 0 == memcmp (&place_pub_key, host_pub_key, sizeof (*host_pub_key)))
  {
    hst = GNUNET_SOCIAL_host_enter_reconnect (hconn, slicer_create (), host_reconnected,
                                              host_answer_door, host_farewell, NULL);
    plc = GNUNET_SOCIAL_host_get_place (hst);
  }
}


/**
 * Callback notifying about a guest place available for reconnection.
 */
static void
app_recv_guest (void *cls,
                struct GNUNET_SOCIAL_GuestConnection *gconn,
                struct GNUNET_SOCIAL_Ego *ego,
                const struct GNUNET_CRYPTO_EddsaPublicKey *guest_pub_key,
                enum GNUNET_SOCIAL_AppPlaceState place_state)
{
  char *guest_pub_str = GNUNET_CRYPTO_eddsa_public_key_to_string (guest_pub_key);
  printf ("Guest\t%s\n", guest_pub_str);
  GNUNET_free (guest_pub_str);

  if ((op_guest_reconnect || op_guest_leave || op_guest_talk
       || op_replay || op_replay_latest
       || op_look_at || op_look_for)
      && 0 == memcmp (&place_pub_key, guest_pub_key, sizeof (*guest_pub_key)))
  {
    gst = GNUNET_SOCIAL_guest_enter_reconnect (gconn, GNUNET_PSYC_SLAVE_JOIN_NONE,
                                               slicer_create (), guest_reconnected, NULL);
    plc = GNUNET_SOCIAL_guest_get_place (gst);
  }
}


/**
 * Callback notifying about an available ego.
 */
static void
app_recv_ego (void *cls,
              struct GNUNET_SOCIAL_Ego *e,
              const struct GNUNET_CRYPTO_EcdsaPublicKey *pub_key,
              const char *name)
{
  char *s = GNUNET_CRYPTO_ecdsa_public_key_to_string (pub_key);
  printf ("Ego\t%s\t%s\n", s, name);
  GNUNET_free (s);

  if (0 == memcmp (&ego_pub_key, pub_key, sizeof (*pub_key))
      || (NULL != opt_ego && 0 == strcmp (opt_ego, name)))
  {
    ego = e;
  }

}



/**
 * Establish application connection to receive available egos and places.
 */
static void
app_connect (void *cls)
{
  app = GNUNET_SOCIAL_app_connect (cfg, opt_app,
                                   app_recv_ego,
                                   app_recv_host,
                                   app_recv_guest,
                                   app_connected,
                                   NULL);
}


/**
 * Main function run by the scheduler.
 *
 * @param cls closure
 * @param args remaining command-line arguments
 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 * @param c configuration
 */
static void
run (void *cls, char *const *args, const char *cfgfile,
     const struct GNUNET_CONFIGURATION_Handle *c)
{
  cfg = c;
  GNUNET_CRYPTO_get_peer_identity (cfg, &this_peer);

  if (!opt_method)
    opt_method = "message";
  if (!opt_data)
    opt_data = "";
  if (!opt_name)
    opt_name = "";

  if (! (op_status
         || op_host_enter || op_host_reconnect || op_host_leave
         || op_host_announce || op_host_assign
         || op_guest_enter || op_guest_reconnect
         || op_guest_leave || op_guest_talk
         || op_replay || op_replay_latest
         || op_look_at || op_look_for))
  {
    op_status = 1;
    fputs("Caution: This tool does not produce correct binary safe PSYC syntax.\n\n", stderr);
  }

  GNUNET_SCHEDULER_add_shutdown (scheduler_shutdown, NULL);
  if (!opt_follow)
  {
    timeout_task = GNUNET_SCHEDULER_add_delayed (TIMEOUT, timeout, NULL);
  }

  if ((op_host_reconnect || op_host_leave || op_host_announce || op_host_assign
       || op_guest_reconnect || (op_guest_enter && !opt_gns)
       || op_guest_leave || op_guest_talk
       || op_replay || op_replay_latest
       || op_look_at || op_look_for)
      && (!opt_place
          || GNUNET_OK != GNUNET_CRYPTO_eddsa_public_key_from_string (opt_place,
                                                                      strlen (opt_place),
                                                                      &place_pub_key)))
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                _("--place missing or invalid.\n"));
    /* FIXME: why does it segfault here? */
    exit_fail ();
    return;
  }

  if (opt_ego)
  {
    if (GNUNET_OK !=
        GNUNET_CRYPTO_ecdsa_public_key_from_string (opt_ego,
                                                strlen (opt_ego),
                                                &ego_pub_key))
    {
      fprintf (stderr,
               _("Public key `%s' malformed\n"),
               opt_ego);
      exit_fail ();
      return;
    }
  }

  GNUNET_SCHEDULER_add_now (app_connect, NULL);
}


/**
 * The main function to obtain peer information.
 *
 * @param argc number of arguments from the command line
 * @param argv command line arguments
 * @return 0 ok, 1 on error
 */
int
main (int argc, char *const *argv)
{
  int res;
  struct GNUNET_GETOPT_CommandLineOption options[] = {
    /*
     * gnunet program options in addition to the ones below:
     *
     * -c, --config=FILENAME
     * -l, --logfile=LOGFILE
     * -L, --log=LOGLEVEL
     * -h, --help
     * -v, --version
     */

    /* operations */

    GNUNET_GETOPT_option_flag ('A',
                                  "host-assign",
                                  gettext_noop ("assign --name in state to --data"),
                                  &op_host_assign),

    GNUNET_GETOPT_option_flag ('B',
                                  "guest-leave",
                                  gettext_noop ("say good-bye and leave somebody else's place"),
                                  &op_guest_leave),

    GNUNET_GETOPT_option_flag ('C',
                                  "host-enter",
                                  gettext_noop ("create a place"),
                                  &op_host_enter),

    GNUNET_GETOPT_option_flag ('D',
                                  "host-leave",
                                  gettext_noop ("destroy a place we were hosting"),
                                  &op_host_leave),

    GNUNET_GETOPT_option_flag ('E',
                                  "guest-enter",
                                  gettext_noop ("enter somebody else's place"),
                                  &op_guest_enter),


    GNUNET_GETOPT_option_flag ('F',
                                  "look-for",
                                  gettext_noop ("find state matching name prefix"),
                                  &op_look_for),

    GNUNET_GETOPT_option_flag ('H',
                                  "replay-latest",
                                  gettext_noop ("replay history of messages up to the given --limit"),
                                  &op_replay_latest),

    GNUNET_GETOPT_option_flag ('N',
                                  "host-reconnect",
                                  gettext_noop ("reconnect to a previously created place"),
                                  &op_host_reconnect),

    GNUNET_GETOPT_option_flag ('P',
                                  "host-announce",
                                  gettext_noop ("publish something to a place we are hosting"),
                                  &op_host_announce),

    GNUNET_GETOPT_option_flag ('R',
                                  "guest-reconnect",
                                  gettext_noop ("reconnect to a previously entered place"),
                                  &op_guest_reconnect),

    GNUNET_GETOPT_option_flag ('S',
                                  "look-at",
                                  gettext_noop ("search for state matching exact name"),
                                  &op_look_at),

    GNUNET_GETOPT_option_flag ('T',
                                  "guest-talk",
                                  gettext_noop ("submit something to somebody's place"),
                                  &op_guest_talk),

    GNUNET_GETOPT_option_flag ('U',
                                  "status",
                                  gettext_noop ("list of egos and subscribed places"),
                                  &op_status),

    GNUNET_GETOPT_option_flag ('X',
                                  "replay",
                                  gettext_noop ("extract and replay history between message IDs --start and --until"),
                                  &op_replay),


    /* options */

    GNUNET_GETOPT_option_string ('a',
                                 "app",
                                 "APPLICATION_ID",
                                 gettext_noop ("application ID to use when connecting"),
                                 &opt_app),

    GNUNET_GETOPT_option_string ('d',
                                 "data",
                                 "DATA",
                                 gettext_noop ("message body or state value"),
                                 &opt_data),

    GNUNET_GETOPT_option_string ('e',
                                 "ego",
                                 "NAME|PUBKEY",
                                 gettext_noop ("name or public key of ego"),
                                 &opt_ego),

    GNUNET_GETOPT_option_flag ('f',
                                  "follow",
                                  gettext_noop ("wait for incoming messages"),
                                  &opt_follow),

    GNUNET_GETOPT_option_string ('g',
                                 "gns",
                                 "GNS_NAME",
                                 gettext_noop ("GNS name"),
                                 &opt_gns),

    GNUNET_GETOPT_option_string ('i',
                                 "peer",
                                 "PEER_ID",
                                 gettext_noop ("peer ID for --guest-enter"),
                                 &opt_peer),

    GNUNET_GETOPT_option_string ('k',
                                 "name",
                                 "VAR_NAME",
                                 gettext_noop ("name (key) to query from state"),
                                 &opt_name),

    GNUNET_GETOPT_option_string ('m',
                                 "method",
                                 "METHOD_NAME",
                                 gettext_noop ("method name"),
                                 &opt_method),

    GNUNET_GETOPT_option_ulong ('n',
                                    "limit",
                                    NULL,
                                    gettext_noop ("number of messages to replay from history"),
                                    &opt_limit),

    GNUNET_GETOPT_option_string ('p',
                                 "place",
                                 "PUBKEY",
                                 gettext_noop ("key address of place"),
                                 &opt_place),

    GNUNET_GETOPT_option_ulong ('s',
                                    "start",
                                    NULL,
                                    gettext_noop ("start message ID for history replay"),
                                    &opt_start),

    GNUNET_GETOPT_option_flag ('w',
                                  "welcome",
                                  gettext_noop ("respond to entry requests by admitting all guests"),
                                  &opt_welcome),

    GNUNET_GETOPT_option_ulong ('u',
                                    "until",
                                    NULL,
                                    gettext_noop ("end message ID for history replay"),
                                    &opt_until),

    GNUNET_GETOPT_option_flag ('y',
                                  "deny",
                                  gettext_noop ("respond to entry requests by refusing all guests"),
                                  &opt_deny),

    GNUNET_GETOPT_OPTION_END
  };

  if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv))
    return 2;

  const char *help =
    _ ("gnunet-social - Interact with the social service: enter/leave, send/receive messages, access history and state.\n");
  const char *usage =
    "gnunet-social [--status]\n"
    "\n"
    "gnunet-social --host-enter --ego <NAME or PUBKEY> [--follow] [--welcome | --deny]\n"
    "gnunet-social --host-reconnect --place <PUBKEY> [--follow] [--welcome | --deny]\n"
    "gnunet-social --host-leave --place <PUBKEY>\n"
    "gnunet-social --host-assign --place <PUBKEY> --name <NAME> --data <VALUE>\n"
// FIXME: some state ops not implemented yet (no hurry)
//  "gnunet-social --host-augment --place <PUBKEY> --name <NAME> --data <VALUE>\n"
//  "gnunet-social --host-diminish --place <PUBKEY> --name <NAME> --data <VALUE>\n"
//  "gnunet-social --host-set --place <PUBKEY> --name <NAME> --data <VALUE>\n"
    "gnunet-social --host-announce --place <PUBKEY> --method <METHOD_NAME> --data <MESSAGE_BODY>\n"
    "\n"
    "gnunet-social --guest-enter --place <PUBKEY> --peer <PEERID> --ego <NAME or PUBKEY> [--follow]\n"
    "gnunet-social --guest-enter --gns <GNS_NAME> --ego <NAME or PUBKEY> [--follow]\n"
    "gnunet-social --guest-reconnect --place <PUBKEY> [--follow]\n"
    "gnunet-social --guest-leave --place <PUBKEY>\n"
    "gnunet-social --guest-talk --place <PUBKEY> --method <METHOD_NAME> --data <MESSAGE_BODY>\n"
    "\n"
    "gnunet-social --replay --place <PUBKEY> --start <MSGID> --until <MSGID>  [--method <METHOD_PREFIX>]\n"
    "gnunet-social --replay-latest --place <PUBKEY> --limit <MSG_LIMIT> [--method <METHOD_PREFIX>]\n"
    "\n"
    "gnunet-social --look-at --place <PUBKEY> --name <FULL_NAME>\n"
    "gnunet-social --look-for --place <PUBKEY> --name <NAME_PREFIX>\n";

  res = GNUNET_PROGRAM_run (argc, argv, help, usage, options, &run, NULL);

  GNUNET_free_nz ((void *) argv);

  if (GNUNET_OK == res)
    return ret;
  else
    return 1;
}