gnunet-nat-auto_legacy.c

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/*
     This file is part of GNUnet.
     Copyright (C) 2011, 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
 */

#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_nat_lib.h"
#include "nat.h"

#define LOG(kind, ...) GNUNET_log_from(kind, "nat", __VA_ARGS__)

#define NAT_SERVER_TIMEOUT \
  GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)

struct NatActivity {
  struct NatActivity *next;

  struct NatActivity *prev;

  struct GNUNET_NETWORK_Handle *sock;

  struct GNUNET_NAT_Test *h;

  struct GNUNET_SCHEDULER_Task *rtask;
};


struct ClientActivity {
  struct ClientActivity *next;

  struct ClientActivity *prev;

  struct GNUNET_MQ_Handle *mq;

  struct GNUNET_NAT_Test *h;
};


struct GNUNET_NAT_Test {
  const struct GNUNET_CONFIGURATION_Handle *cfg;

  GNUNET_NAT_TestCallback report;

  void *report_cls;

  struct GNUNET_NAT_Handle *nat;

  struct GNUNET_NETWORK_Handle *lsock;

  struct NatActivity *na_head;

  struct NatActivity *na_tail;

  struct ClientActivity *ca_head;

  struct ClientActivity *ca_tail;

  struct GNUNET_SCHEDULER_Task *ltask;

  struct GNUNET_SCHEDULER_Task *ttask;

  int is_tcp;

  uint16_t data;

  uint16_t adv_port;

  enum GNUNET_NAT_StatusCode status;
};


static void
reversal_cb(void *cls, const struct sockaddr *addr, socklen_t addrlen)
{
  struct GNUNET_NAT_Test *h = cls;
  const struct sockaddr_in *sa;

  if (sizeof(struct sockaddr_in) != addrlen)
    return;
  sa = (const struct sockaddr_in *)addr;
  if (h->data != sa->sin_port)
    {
      LOG(GNUNET_ERROR_TYPE_DEBUG,
          "Received connection reversal request for wrong port\n");
      return; /* wrong port */
    }
  /* report success */
  h->report(h->report_cls, GNUNET_NAT_ERROR_SUCCESS);
}


static void
do_udp_read(void *cls)
{
  struct GNUNET_NAT_Test *tst = cls;
  uint16_t data;
  const struct GNUNET_SCHEDULER_TaskContext *tc;

  tc = GNUNET_SCHEDULER_get_task_context();
  tst->ltask = GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL,
                                             tst->lsock,
                                             &do_udp_read,
                                             tst);
  if ((NULL != tc->write_ready) &&
      (GNUNET_NETWORK_fdset_isset(tc->read_ready, tst->lsock)) &&
      (sizeof(data) ==
       GNUNET_NETWORK_socket_recv(tst->lsock, &data, sizeof(data))))
    {
      if (data == tst->data)
        tst->report(tst->report_cls, GNUNET_NAT_ERROR_SUCCESS);
      else
        LOG(GNUNET_ERROR_TYPE_DEBUG,
            "Received data mismatches expected value\n");
    }
  else
    LOG(GNUNET_ERROR_TYPE_DEBUG,
        "Failed to receive data from inbound connection\n");
}


static void
do_read(void *cls)
{
  struct NatActivity *na = cls;
  struct GNUNET_NAT_Test *tst;
  uint16_t data;
  const struct GNUNET_SCHEDULER_TaskContext *tc;

  tc = GNUNET_SCHEDULER_get_task_context();
  na->rtask = NULL;
  tst = na->h;
  GNUNET_CONTAINER_DLL_remove(tst->na_head, tst->na_tail, na);
  if ((NULL != tc->write_ready) &&
      (GNUNET_NETWORK_fdset_isset(tc->read_ready, na->sock)) &&
      (sizeof(data) ==
       GNUNET_NETWORK_socket_recv(na->sock, &data, sizeof(data))))
    {
      if (data == tst->data)
        tst->report(tst->report_cls, GNUNET_NAT_ERROR_SUCCESS);
      else
        LOG(GNUNET_ERROR_TYPE_DEBUG,
            "Received data does not match expected value\n");
    }
  else
    LOG(GNUNET_ERROR_TYPE_DEBUG,
        "Failed to receive data from inbound connection\n");
  GNUNET_NETWORK_socket_close(na->sock);
  GNUNET_free(na);
}


static void
do_accept(void *cls)
{
  struct GNUNET_NAT_Test *tst = cls;
  struct GNUNET_NETWORK_Handle *s;
  struct NatActivity *wl;

  tst->ltask = GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL,
                                             tst->lsock,
                                             &do_accept,
                                             tst);
  s = GNUNET_NETWORK_socket_accept(tst->lsock, NULL, NULL);
  if (NULL == s)
    {
      GNUNET_log_strerror(GNUNET_ERROR_TYPE_INFO, "accept");
      return; /* odd error */
    }
  LOG(GNUNET_ERROR_TYPE_DEBUG,
      "Got an inbound connection, waiting for data\n");
  wl = GNUNET_new(struct NatActivity);
  wl->sock = s;
  wl->h = tst;
  wl->rtask = GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL,
                                            wl->sock,
                                            &do_read,
                                            wl);
  GNUNET_CONTAINER_DLL_insert(tst->na_head, tst->na_tail, wl);
}


static void
mq_error_handler(void *cls, enum GNUNET_MQ_Error error)
{
  struct ClientActivity *ca = cls;
  struct GNUNET_NAT_Test *tst = ca->h;

  GNUNET_CONTAINER_DLL_remove(tst->ca_head, tst->ca_tail, ca);
  GNUNET_MQ_destroy(ca->mq);
  GNUNET_free(ca);
}


static void
addr_cb(void *cls,
        int add_remove,
        const struct sockaddr *addr,
        socklen_t addrlen)
{
  struct GNUNET_NAT_Test *h = cls;
  struct ClientActivity *ca;
  struct GNUNET_MQ_Envelope *env;
  struct GNUNET_NAT_TestMessage *msg;
  const struct sockaddr_in *sa;

  if (GNUNET_YES != add_remove)
    return;
  if (addrlen != sizeof(struct sockaddr_in))
    {
      LOG(GNUNET_ERROR_TYPE_DEBUG,
          "NAT test ignores IPv6 address `%s' returned from NAT library\n",
          GNUNET_a2s(addr, addrlen));
      return; /* ignore IPv6 here */
    }
  LOG(GNUNET_ERROR_TYPE_INFO,
      "Asking gnunet-nat-server to connect to `%s'\n",
      GNUNET_a2s(addr, addrlen));

  ca = GNUNET_new(struct ClientActivity);
  ca->h = h;
  ca->mq = GNUNET_CLIENT_connect(h->cfg,
                                 "gnunet-nat-server",
                                 NULL,
                                 &mq_error_handler,
                                 ca);
  if (NULL == ca->mq)
    {
      GNUNET_free(ca);
      GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
                 _("Failed to connect to `gnunet-nat-server'\n"));
      return;
    }
  GNUNET_CONTAINER_DLL_insert(h->ca_head, h->ca_tail, ca);
  sa = (const struct sockaddr_in *)addr;
  env = GNUNET_MQ_msg(msg, GNUNET_MESSAGE_TYPE_NAT_TEST);
  msg->dst_ipv4 = sa->sin_addr.s_addr;
  msg->dport = sa->sin_port;
  msg->data = h->data;
  msg->is_tcp = htonl((uint32_t)h->is_tcp);
  GNUNET_MQ_send(ca->mq, env);
}


static void
do_timeout(void *cls)
{
  struct GNUNET_NAT_Test *nh = cls;

  nh->ttask = NULL;
  nh->report(nh->report_cls,
             (GNUNET_NAT_ERROR_SUCCESS == nh->status)
             ? GNUNET_NAT_ERROR_TIMEOUT
             : nh->status);
}


struct GNUNET_NAT_Test *
GNUNET_NAT_test_start(const struct GNUNET_CONFIGURATION_Handle *cfg,
                      int is_tcp,
                      uint16_t bnd_port,
                      uint16_t adv_port,
                      struct GNUNET_TIME_Relative timeout,
                      GNUNET_NAT_TestCallback report,
                      void *report_cls)
{
  struct GNUNET_NAT_Test *nh;
  struct sockaddr_in sa;
  const struct sockaddr *addrs[] = { (const struct sockaddr *)&sa };
  const socklen_t addrlens[] = { sizeof(sa) };

  memset(&sa, 0, sizeof(sa));
  sa.sin_family = AF_INET;
  sa.sin_port = htons(bnd_port);
#if HAVE_SOCKADDR_IN_SIN_LEN
  sa.sin_len = sizeof(sa);
#endif

  nh = GNUNET_new(struct GNUNET_NAT_Test);
  nh->cfg = cfg;
  nh->is_tcp = is_tcp;
  nh->data = bnd_port;
  nh->adv_port = adv_port;
  nh->report = report;
  nh->report_cls = report_cls;
  nh->status = GNUNET_NAT_ERROR_SUCCESS;
  if (0 == bnd_port)
    {
      nh->nat = GNUNET_NAT_register(cfg,
                                    is_tcp,
                                    0,
                                    0,
                                    NULL,
                                    NULL,
                                    &addr_cb,
                                    &reversal_cb,
                                    nh,
                                    NULL);
    }
  else
    {
      nh->lsock =
        GNUNET_NETWORK_socket_create(AF_INET,
                                     (is_tcp == GNUNET_YES) ? SOCK_STREAM
                                     : SOCK_DGRAM,
                                     0);
      if ((nh->lsock == NULL) ||
          (GNUNET_OK != GNUNET_NETWORK_socket_bind(nh->lsock,
                                                   (const struct sockaddr *)&sa,
                                                   sizeof(sa))))
        {
          GNUNET_log(
            GNUNET_ERROR_TYPE_ERROR,
            _("Failed to create listen socket bound to `%s' for NAT test: %s\n"),
            GNUNET_a2s((const struct sockaddr *)&sa, sizeof(sa)),
            strerror(errno));
          if (NULL != nh->lsock)
            {
              GNUNET_NETWORK_socket_close(nh->lsock);
              nh->lsock = NULL;
            }
          nh->status = GNUNET_NAT_ERROR_INTERNAL_NETWORK_ERROR;
          nh->ttask = GNUNET_SCHEDULER_add_now(&do_timeout, nh);
          return nh;
        }
      if (GNUNET_YES == is_tcp)
        {
          GNUNET_break(GNUNET_OK == GNUNET_NETWORK_socket_listen(nh->lsock, 5));
          nh->ltask = GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL,
                                                    nh->lsock,
                                                    &do_accept,
                                                    nh);
        }
      else
        {
          nh->ltask = GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL,
                                                    nh->lsock,
                                                    &do_udp_read,
                                                    nh);
        }
      LOG(GNUNET_ERROR_TYPE_INFO,
          "NAT test listens on port %u (%s)\n",
          bnd_port,
          (GNUNET_YES == is_tcp) ? "tcp" : "udp");
      nh->nat = GNUNET_NAT_register(cfg,
                                    is_tcp,
                                    adv_port,
                                    1,
                                    addrs,
                                    addrlens,
                                    &addr_cb,
                                    NULL,
                                    nh,
                                    NULL);
      if (NULL == nh->nat)
        {
          LOG(GNUNET_ERROR_TYPE_INFO,
              _("NAT test failed to start NAT library\n"));
          if (NULL != nh->ltask)
            {
              GNUNET_SCHEDULER_cancel(nh->ltask);
              nh->ltask = NULL;
            }
          if (NULL != nh->lsock)
            {
              GNUNET_NETWORK_socket_close(nh->lsock);
              nh->lsock = NULL;
            }
          nh->status = GNUNET_NAT_ERROR_NAT_REGISTER_FAILED;
          nh->ttask = GNUNET_SCHEDULER_add_now(&do_timeout, nh);
          return nh;
        }
    }
  nh->ttask = GNUNET_SCHEDULER_add_delayed(timeout, &do_timeout, nh);
  return nh;
}


void
GNUNET_NAT_test_stop(struct GNUNET_NAT_Test *tst)
{
  struct NatActivity *pos;
  struct ClientActivity *cpos;

  LOG(GNUNET_ERROR_TYPE_DEBUG, "Stopping NAT test\n");
  while (NULL != (cpos = tst->ca_head))
    {
      GNUNET_CONTAINER_DLL_remove(tst->ca_head, tst->ca_tail, cpos);
      GNUNET_MQ_destroy(cpos->mq);
      GNUNET_free(cpos);
    }
  while (NULL != (pos = tst->na_head))
    {
      GNUNET_CONTAINER_DLL_remove(tst->na_head, tst->na_tail, pos);
      GNUNET_SCHEDULER_cancel(pos->rtask);
      GNUNET_NETWORK_socket_close(pos->sock);
      GNUNET_free(pos);
    }
  if (NULL != tst->ttask)
    {
      GNUNET_SCHEDULER_cancel(tst->ttask);
      tst->ttask = NULL;
    }
  if (NULL != tst->ltask)
    {
      GNUNET_SCHEDULER_cancel(tst->ltask);
      tst->ltask = NULL;
    }
  if (NULL != tst->lsock)
    {
      GNUNET_NETWORK_socket_close(tst->lsock);
      tst->lsock = NULL;
    }
  if (NULL != tst->nat)
    {
      GNUNET_NAT_unregister(tst->nat);
      tst->nat = NULL;
    }
  GNUNET_free(tst);
}

/* end of nat_test.c */