Example #1
0
/**
 * gnutls_bye:
 * @session: is a #gnutls_session_t structure.
 * @how: is an integer
 *
 * Terminates the current TLS/SSL connection. The connection should
 * have been initiated using gnutls_handshake().  @how should be one
 * of %GNUTLS_SHUT_RDWR, %GNUTLS_SHUT_WR.
 *
 * In case of %GNUTLS_SHUT_RDWR the TLS session gets
 * terminated and further receives and sends will be disallowed.  If
 * the return value is zero you may continue using the underlying
 * transport layer. %GNUTLS_SHUT_RDWR sends an alert containing a close
 * request and waits for the peer to reply with the same message.
 *
 * In case of %GNUTLS_SHUT_WR the TLS session gets terminated
 * and further sends will be disallowed. In order to reuse the
 * connection you should wait for an EOF from the peer.
 * %GNUTLS_SHUT_WR sends an alert containing a close request.
 *
 * Note that not all implementations will properly terminate a TLS
 * connection.  Some of them, usually for performance reasons, will
 * terminate only the underlying transport layer, and thus not
 * distinguishing between a malicious party prematurely terminating 
 * the connection and normal termination. 
 *
 * This function may also return %GNUTLS_E_AGAIN or
 * %GNUTLS_E_INTERRUPTED; cf.  gnutls_record_get_direction().
 *
 * Returns: %GNUTLS_E_SUCCESS on success, or an error code, see
 *   function documentation for entire semantics.
 **/
int
gnutls_bye (gnutls_session_t session, gnutls_close_request_t how)
{
  int ret = 0;

  switch (STATE)
    {
    case STATE0:
    case STATE60:
      ret = _gnutls_io_write_flush (session);
      STATE = STATE60;
      if (ret < 0)
        {
          gnutls_assert ();
          return ret;
        }

    case STATE61:
      ret =
        gnutls_alert_send (session, GNUTLS_AL_WARNING, GNUTLS_A_CLOSE_NOTIFY);
      STATE = STATE61;
      if (ret < 0)
        {
          gnutls_assert ();
          return ret;
        }

    case STATE62:
      STATE = STATE62;
      if (how == GNUTLS_SHUT_RDWR)
        {
          do
            {
              ret = _gnutls_recv_int (session, GNUTLS_ALERT, -1, NULL, 0, NULL, 
                                      session->internals.record_timeout_ms);
            }
          while (ret == GNUTLS_E_GOT_APPLICATION_DATA);

          if (ret >= 0)
            session->internals.may_not_read = 1;

          if (ret < 0)
            {
              gnutls_assert ();
              return ret;
            }
        }
      STATE = STATE62;

      break;
    default:
      gnutls_assert ();
      return GNUTLS_E_INTERNAL_ERROR;
    }

  STATE = STATE0;

  session->internals.may_not_write = 1;
  return 0;
}
Example #2
0
/**
 * gnutls_heartbeat_pong:
 * @session: is a #gnutls_session_t structure.
 * @flags: should be zero
 *
 * This function replies to a ping by sending a pong to the peer.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, otherwise a negative error code.
 *
 * Since: 3.1.2
 **/
int gnutls_heartbeat_pong(gnutls_session_t session, unsigned int flags)
{
	int ret;

	if (session->internals.record_send_buffer.byte_length > 0 &&
	    session->internals.record_send_buffer.head != NULL &&
	    session->internals.record_send_buffer.head->type ==
	    GNUTLS_HEARTBEAT)
		return _gnutls_io_write_flush(session);

	if (session->internals.hb_remote_data.length == 0)
		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

	ret =
	    heartbeat_send_data(session,
				session->internals.hb_remote_data.data,
				session->internals.hb_remote_data.length,
				HEARTBEAT_RESPONSE);

	_gnutls_buffer_reset(&session->internals.hb_remote_data);

	if (ret < 0)
		return gnutls_assert_val(ret);

	return 0;
}
Example #3
0
/* This function writes the data that are left in the
 * Handshake write buffer (ie. because the previous write was
 * interrupted.
 *
 */
ssize_t
_gnutls_handshake_io_write_flush (gnutls_session_t session)
{
  mbuffer_head_st *const send_buffer =
    &session->internals.handshake_send_buffer;
  gnutls_datum_t msg;
  int ret;
  uint16_t epoch;
  ssize_t total = 0;
  mbuffer_st *cur;

  _gnutls_write_log ("HWRITE FLUSH: %d bytes in buffer.\n",
                     (int) send_buffer->byte_length);

  if (IS_DTLS(session))
    return _dtls_transmit(session);

  for (cur = _mbuffer_head_get_first (send_buffer, &msg);
       cur != NULL; cur = _mbuffer_head_get_first (send_buffer, &msg))
    {
      epoch = cur->epoch;

      ret = _gnutls_send_int (session, cur->type,
                              cur->htype,
                              epoch,
                              msg.data, msg.size, 0);

      if (ret >= 0)
        {
          total += ret;
          
          ret = _mbuffer_head_remove_bytes (send_buffer, ret);
          if (ret == 1)
            _gnutls_epoch_refcount_dec(session, epoch);

          _gnutls_write_log ("HWRITE: wrote %d bytes, %d bytes left.\n",
                             ret, (int) send_buffer->byte_length);

        }
      else
        {
          _gnutls_write_log ("HWRITE error: code %d, %d bytes left.\n",
                             ret, (int) send_buffer->byte_length);

          gnutls_assert ();
          return ret;
        }
    }

  return _gnutls_io_write_flush (session);
}
Example #4
0
/* This function is to be called if the handshake was successfully 
 * completed. This sends a Change Cipher Spec packet to the peer.
 */
ssize_t
_gnutls_send_change_cipher_spec (gnutls_session_t session, int again)
{
  static const opaque data[1] = { GNUTLS_TYPE_CHANGE_CIPHER_SPEC };

  _gnutls_handshake_log ("REC[%x]: Sent ChangeCipherSpec\n", session);

  if (again == 0)
    return _gnutls_send_int (session, GNUTLS_CHANGE_CIPHER_SPEC, -1, data, 1);
  else
    {
      return _gnutls_io_write_flush (session);
    }
}
Example #5
0
/* This function is like write. But it does not return -1 on error.
 * It does return gnutls_errno instead.
 *
 * This function takes full responsibility of freeing msg->data.
 *
 * In case of E_AGAIN and E_INTERRUPTED errors, you must call
 * gnutls_write_flush(), until it returns ok (0).
 *
 * We need to push exactly the data in msg->size, since we cannot send
 * less data. In TLS the peer must receive the whole packet in order
 * to decrypt and verify the integrity.
 *
 */
ssize_t
_gnutls_io_write_buffered (gnutls_session_t session,
                           mbuffer_st * bufel, unsigned int mflag)
{
  mbuffer_head_st *const send_buffer = &session->internals.record_send_buffer;

  _mbuffer_enqueue (send_buffer, bufel);

  _gnutls_write_log
    ("WRITE: enqueued %d bytes for %p. Total %d bytes.\n",
     (int) bufel->msg.size, session->internals.transport_recv_ptr,
     (int) send_buffer->byte_length);

  if (mflag == MBUFFER_FLUSH)
    return _gnutls_io_write_flush (session);
  else
    return bufel->msg.size;
}
Example #6
0
/* This function transmits the flight that has been previously
 * buffered.
 *
 * This function is called from the handshake layer and calls the
 * record layer.
 */
int
_dtls_transmit (gnutls_session_t session)
{
int ret;
uint8_t* buf = NULL;
unsigned int timeout;

  /* PREPARING -> SENDING state transition */
  mbuffer_head_st *const send_buffer =
    &session->internals.handshake_send_buffer;
  mbuffer_st *cur;
  gnutls_handshake_description_t last_type = 0;
  unsigned int diff;
  struct timespec now;
  
  gettime(&now);

  /* If we have already sent a flight and we are operating in a 
   * non blocking way, check if it is time to retransmit or just
   * return.
   */
  if (session->internals.dtls.flight_init != 0 && session->internals.dtls.blocking == 0)
    {
      /* just in case previous run was interrupted */
      ret = _gnutls_io_write_flush (session);
      if (ret < 0)
        {
          gnutls_assert();
          goto cleanup;
        }

      if (session->internals.dtls.last_flight == 0 || !_dtls_is_async(session))
        {
          /* check for ACK */
          ret = _gnutls_io_check_recv(session, 0);
          if (ret == GNUTLS_E_TIMEDOUT)
            {
              /* if no retransmission is required yet just return 
               */
              if (_dtls_timespec_sub_ms(&now, &session->internals.dtls.last_retransmit) < TIMER_WINDOW)
                {
                  gnutls_assert();
                  goto nb_timeout;
                }
            }
          else /* received something */
            {
              if (ret == 0)
                {
                  ret = is_next_hpacket_expected(session);
                  if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
                    goto nb_timeout;
                  if (ret < 0 && ret != GNUTLS_E_UNEXPECTED_HANDSHAKE_PACKET)
                    {
                      gnutls_assert();
                      goto cleanup;
                    }
                  if (ret == 0) goto end_flight;
                  /* if ret == GNUTLS_E_UNEXPECTED_HANDSHAKE_PACKET retransmit */
                }
              else
                goto nb_timeout;
            }
        }
    }

  do 
    {
      timeout = TIMER_WINDOW;

      diff = _dtls_timespec_sub_ms(&now, &session->internals.dtls.handshake_start_time);
      if (diff >= session->internals.dtls.total_timeout_ms) 
        {
          _gnutls_dtls_log("Session timeout: %u ms\n", diff);
          ret = gnutls_assert_val(GNUTLS_E_TIMEDOUT);
          goto end_flight;
        }

      diff = _dtls_timespec_sub_ms(&now, &session->internals.dtls.last_retransmit);
      if (session->internals.dtls.flight_init == 0 || diff >= TIMER_WINDOW)
        {
          _gnutls_dtls_log ("DTLS[%p]: %sStart of flight transmission.\n", session,  (session->internals.dtls.flight_init == 0)?"":"re-");
          for (cur = send_buffer->head;
               cur != NULL; cur = cur->next)
            {
              ret = transmit_message (session, cur, &buf);
              if (ret < 0)
                {
                  gnutls_assert();
                  goto end_flight;
                }

              last_type = cur->htype;
            }
          gettime(&session->internals.dtls.last_retransmit);

          if (session->internals.dtls.flight_init == 0)
            {
              session->internals.dtls.flight_init = 1;
              RESET_TIMER;
              timeout = TIMER_WINDOW;

              if (last_type == GNUTLS_HANDSHAKE_FINISHED)
                {
              /* On the last flight we cannot ensure retransmission
               * from here. _dtls_wait_and_retransmit() is being called
               * by handshake.
               */
                  session->internals.dtls.last_flight = 1;
                }
              else
                session->internals.dtls.last_flight = 0;
            }
          else
            {
              UPDATE_TIMER;
            }
        }

      ret = _gnutls_io_write_flush (session);
      if (ret < 0)
        {
          ret = gnutls_assert_val(ret);
          goto cleanup;
        }

      /* last message in handshake -> no ack */
      if (session->internals.dtls.last_flight != 0)
        {
          /* we don't wait here. We just return 0 and
           * if a retransmission occurs because peer didn't receive it
           * we rely on the record or handshake
           * layer calling this function again.
           */
          ret = 0;
          goto cleanup;
        }
      else /* all other messages -> implicit ack (receive of next flight) */
        {
          if (session->internals.dtls.blocking != 0)
            ret = _gnutls_io_check_recv(session, timeout);
          else
            {
              ret = _gnutls_io_check_recv(session, 0);
              if (ret == GNUTLS_E_TIMEDOUT)
                {
                  goto nb_timeout;
                }
            }
          
          if (ret == 0)
            {
              ret = is_next_hpacket_expected(session);
              if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
                goto nb_timeout;

              if (ret == GNUTLS_E_UNEXPECTED_HANDSHAKE_PACKET)
                {
                  ret = GNUTLS_E_TIMEDOUT;
                  goto keep_up;
                }
              if (ret < 0)
                {
                  gnutls_assert();
                  goto cleanup;
                }
              goto end_flight;
            }
        }

keep_up:
      gettime(&now);
    } while(ret == GNUTLS_E_TIMEDOUT);

  if (ret < 0)
    {
      ret = gnutls_assert_val(ret);
      goto end_flight;
    }

  ret = 0;

end_flight:
  _gnutls_dtls_log ("DTLS[%p]: End of flight transmission.\n", session);
  _dtls_reset_hsk_state(session);

cleanup:
  if (buf != NULL)
    gnutls_free(buf);

  /* SENDING -> WAITING state transition */
  return ret;

nb_timeout:
  if (buf != NULL)
    gnutls_free(buf);

  RETURN_DTLS_EAGAIN_OR_TIMEOUT(session, ret);
}
Example #7
0
/* This function behaves exactly like write(). The only difference is
 * that it accepts, the gnutls_session_t and the content_type_t of data to
 * send (if called by the user the Content is specific)
 * It is intended to transfer data, under the current session.    
 *
 * @type: The content type to send
 * @htype: If this is a handshake message then the handshake type
 * @epoch_rel: %EPOCH_READ_* or %EPOCH_WRITE_*
 * @data: the data to be sent
 * @data_size: the size of the @data
 * @target_length: @data_size + minimum required padding
 * @mflags: zero or %MBUFFER_FLUSH
 *
 * Oct 30 2001: Removed capability to send data more than MAX_RECORD_SIZE.
 * This makes the function much easier to read, and more error resistant
 * (there were cases were the old function could mess everything up).
 * --nmav
 *
 * This function may accept a NULL pointer for data, and 0 for size, if
 * and only if the previous send was interrupted for some reason.
 *
 */
ssize_t
_gnutls_send_tlen_int (gnutls_session_t session, content_type_t type,
		gnutls_handshake_description_t htype,
		unsigned int epoch_rel, const void *_data,
		size_t data_size, size_t target_length, unsigned int mflags)
{
  mbuffer_st *bufel;
  ssize_t cipher_size;
  int retval, ret;
  int send_data_size;
  uint8_t *headers;
  int header_size;
  const uint8_t *data = _data;
  record_parameters_st *record_params;
  record_state_st *record_state;

  ret = _gnutls_epoch_get (session, epoch_rel, &record_params);
  if (ret < 0)
    return gnutls_assert_val(ret);

  /* Safeguard against processing data with an incomplete cipher state. */
  if (!record_params->initialized)
    return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

  record_state = &record_params->write;

  /* Do not allow null pointer if the send buffer is empty.
   * If the previous send was interrupted then a null pointer is
   * ok, and means to resume.
   */
  if (session->internals.record_send_buffer.byte_length == 0 &&
      (data_size == 0 && _data == NULL))
    {
      gnutls_assert ();
      return GNUTLS_E_INVALID_REQUEST;
    }

  if (type != GNUTLS_ALERT)     /* alert messages are sent anyway */
    if (session_is_valid (session) || session->internals.may_not_write != 0)
      {
        gnutls_assert ();
        return GNUTLS_E_INVALID_SESSION;
      }


  if (data_size > MAX_USER_SEND_SIZE(session))
    {
      if (IS_DTLS(session))
        return gnutls_assert_val(GNUTLS_E_LARGE_PACKET);

      send_data_size = MAX_USER_SEND_SIZE(session);
    }
  else
    send_data_size = data_size;
  
  /* Only encrypt if we don't have data to send 
   * from the previous run. - probably interrupted.
   */
  if (mflags != 0 && session->internals.record_send_buffer.byte_length > 0)
    {
      ret = _gnutls_io_write_flush (session);
      if (ret > 0)
        cipher_size = ret;
      else
        cipher_size = 0;

      retval = session->internals.record_send_buffer_user_size;
    }
  else
    {
      if (unlikely((send_data_size == 0 && target_length == 0)))
        return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);

      /* now proceed to packet encryption
       */
      cipher_size = MAX_RECORD_SEND_SIZE(session);
      bufel = _mbuffer_alloc (0, cipher_size+CIPHER_SLACK_SIZE);
      if (bufel == NULL)
        return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);

      headers = _mbuffer_get_uhead_ptr(bufel);
      headers[0] = type;
      /* Use the default record version, if it is
       * set. */
      copy_record_version (session, htype, &headers[1]);
      header_size = RECORD_HEADER_SIZE(session);
      /* Adjust header length and add sequence for DTLS */
      if (IS_DTLS(session))
        memcpy(&headers[3], &record_state->sequence_number.i, 8);

      _gnutls_record_log
        ("REC[%p]: Preparing Packet %s(%d) with length: %d and target length: %d\n", session,
         _gnutls_packet2str (type), type, (int) data_size, (int) target_length);

      _mbuffer_set_udata_size(bufel, cipher_size);
      _mbuffer_set_uhead_size(bufel, header_size);

      ret =
        _gnutls_encrypt (session, 
                         data, send_data_size, target_length, 
                         bufel, type, record_params);
      if (ret <= 0)
        {
          gnutls_assert ();
          if (ret == 0)
            ret = GNUTLS_E_ENCRYPTION_FAILED;
          gnutls_free (bufel);
          return ret;   /* error */
        }

      cipher_size = _mbuffer_get_udata_size(bufel);
      retval = send_data_size;
      session->internals.record_send_buffer_user_size = send_data_size;

      /* increase sequence number
       */
      if (sequence_increment (session, &record_state->sequence_number) != 0)
        {
          session_invalidate (session);
          gnutls_free (bufel);
          return gnutls_assert_val(GNUTLS_E_RECORD_LIMIT_REACHED);
        }

      ret = _gnutls_io_write_buffered (session, bufel, mflags);
    }

  if (ret != cipher_size)
    {
      /* If we have sent any data then just return
       * the error value. Do not invalidate the session.
       */
      if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
        return gnutls_assert_val(ret);

      if (ret > 0)
        ret = gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);

      session_unresumable (session);
      session->internals.may_not_write = 1;
      return gnutls_assert_val(ret);
    }

  session->internals.record_send_buffer_user_size = 0;

  _gnutls_record_log ("REC[%p]: Sent Packet[%d] %s(%d) in epoch %d and length: %d\n",
                      session,
                      (unsigned int)
                      _gnutls_uint64touint32
                      (&record_state->sequence_number),
                      _gnutls_packet2str (type), type, 
                      (int) record_params->epoch,
                      (int) cipher_size);

  return retval;
}
Example #8
0
/* This function behaves exactly like write(). The only difference is
 * that it accepts, the gnutls_session_t and the content_type_t of data to
 * send (if called by the user the Content is specific)
 * It is intended to transfer data, under the current session.    
 *
 * Oct 30 2001: Removed capability to send data more than MAX_RECORD_SIZE.
 * This makes the function much easier to read, and more error resistant
 * (there were cases were the old function could mess everything up).
 * --nmav
 *
 * This function may accept a NULL pointer for data, and 0 for size, if
 * and only if the previous send was interrupted for some reason.
 *
 */
ssize_t
_gnutls_send_int (gnutls_session_t session, content_type_t type,
                  gnutls_handshake_description_t htype,
                  unsigned int epoch_rel, const void *_data,
                  size_t sizeofdata, unsigned int mflags)
{
  mbuffer_st *bufel;
  ssize_t cipher_size;
  int retval, ret;
  int data2send_size;
  uint8_t headers[5];
  const uint8_t *data = _data;
  record_parameters_st *record_params;
  record_state_st *record_state;

  ret = _gnutls_epoch_get (session, epoch_rel, &record_params);
  if (ret < 0)
    {
      gnutls_assert ();
      return ret;
    }

  /* Safeguard against processing data with an incomplete cipher state. */
  if (!record_params->initialized)
    {
      gnutls_assert ();
      return GNUTLS_E_INVALID_REQUEST;
    }

  record_state = &record_params->write;

  /* Do not allow null pointer if the send buffer is empty.
   * If the previous send was interrupted then a null pointer is
   * ok, and means to resume.
   */
  if (session->internals.record_send_buffer.byte_length == 0 &&
      (sizeofdata == 0 && _data == NULL))
    {
      gnutls_assert ();
      return GNUTLS_E_INVALID_REQUEST;
    }

  if (type != GNUTLS_ALERT)     /* alert messages are sent anyway */
    if (session_is_valid (session) || session->internals.may_not_write != 0)
      {
        gnutls_assert ();
        return GNUTLS_E_INVALID_SESSION;
      }

  headers[0] = type;

  /* Use the default record version, if it is
   * set.
   */
  copy_record_version (session, htype, &headers[1]);


  _gnutls_record_log
    ("REC[%p]: Sending Packet[%d] %s(%d) with length: %d\n", session,
     (int) _gnutls_uint64touint32 (&record_state->sequence_number),
     _gnutls_packet2str (type), type, (int) sizeofdata);

  if (sizeofdata > MAX_RECORD_SEND_SIZE)
    data2send_size = MAX_RECORD_SEND_SIZE;
  else
    data2send_size = sizeofdata;

  /* Only encrypt if we don't have data to send 
   * from the previous run. - probably interrupted.
   */
  if (mflags != 0 && session->internals.record_send_buffer.byte_length > 0)
    {
      ret = _gnutls_io_write_flush (session);
      if (ret > 0)
        cipher_size = ret;
      else
        cipher_size = 0;

      retval = session->internals.record_send_buffer_user_size;
    }
  else
    {

      /* now proceed to packet encryption
       */
      cipher_size = data2send_size + MAX_RECORD_OVERHEAD;
      bufel = _mbuffer_alloc (cipher_size, cipher_size);
      if (bufel == NULL)
        {
          gnutls_assert ();
          return GNUTLS_E_MEMORY_ERROR;
        }

      cipher_size =
        _gnutls_encrypt (session, headers, RECORD_HEADER_SIZE, data,
                         data2send_size, _mbuffer_get_udata_ptr (bufel),
                         cipher_size, type,
                         (session->internals.priorities.no_padding ==
                          0) ? 1 : 0, record_params);
      if (cipher_size <= 0)
        {
          gnutls_assert ();
          if (cipher_size == 0)
            cipher_size = GNUTLS_E_ENCRYPTION_FAILED;
          gnutls_free (bufel);
          return cipher_size;   /* error */
        }

      retval = data2send_size;
      session->internals.record_send_buffer_user_size = data2send_size;

      /* increase sequence number
       */
      if (_gnutls_uint64pp (&record_state->sequence_number) != 0)
        {
          session_invalidate (session);
          gnutls_assert ();
          gnutls_free (bufel);
          return GNUTLS_E_RECORD_LIMIT_REACHED;
        }

      _mbuffer_set_udata_size (bufel, cipher_size);
      ret = _gnutls_io_write_buffered (session, bufel, mflags);
    }

  if (ret != cipher_size)
    {
      if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
        {
          /* If we have sent any data then just return
           * the error value. Do not invalidate the session.
           */
          gnutls_assert ();
          return ret;
        }

      if (ret > 0)
        {
          gnutls_assert ();
          ret = GNUTLS_E_INTERNAL_ERROR;
        }
      session_unresumable (session);
      session->internals.may_not_write = 1;
      gnutls_assert ();
      return ret;
    }

  session->internals.record_send_buffer_user_size = 0;

  _gnutls_record_log ("REC[%p]: Sent Packet[%d] %s(%d) with length: %d\n",
                      session,
                      (int)
                      _gnutls_uint64touint32
                      (&record_state->sequence_number),
                      _gnutls_packet2str (type), type, (int) cipher_size);

  return retval;
}
Example #9
0
/**
 * gnutls_heartbeat_ping:
 * @session: is a #gnutls_session_t structure.
 * @data_size: is the length of the ping payload.
 * @max_tries: if flags is %GNUTLS_HEARTBEAT_WAIT then this sets the number of retransmissions. Use zero for indefinite (until timeout).
 * @flags: if %GNUTLS_HEARTBEAT_WAIT then wait for pong or timeout instead of returning immediately.
 *
 * This function sends a ping to the peer. If the @flags is set
 * to %GNUTLS_HEARTBEAT_WAIT then it waits for a reply from the peer.
 * 
 * Note that it is highly recommended to use this function with the
 * flag %GNUTLS_HEARTBEAT_WAIT, or you need to handle retransmissions
 * and timeouts manually.
 *
 * Returns: %GNUTLS_E_SUCCESS on success, otherwise a negative error code.
 *
 * Since: 3.1.2
 **/
int
gnutls_heartbeat_ping(gnutls_session_t session, size_t data_size,
		      unsigned int max_tries, unsigned int flags)
{
	int ret;
	unsigned int retries = 1, diff;
	struct timespec now;

	if (data_size > MAX_HEARTBEAT_LENGTH)
		return
		    gnutls_assert_val(GNUTLS_E_UNEXPECTED_PACKET_LENGTH);

	if (gnutls_heartbeat_allowed
	    (session, GNUTLS_HB_LOCAL_ALLOWED_TO_SEND) == 0)
		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);

	/* resume previous call if interrupted */
	if (session->internals.record_send_buffer.byte_length > 0 &&
	    session->internals.record_send_buffer.head != NULL &&
	    session->internals.record_send_buffer.head->type ==
	    GNUTLS_HEARTBEAT)
		return _gnutls_io_write_flush(session);

	switch (session->internals.hb_state) {
	case SHB_SEND1:
		if (data_size > DEFAULT_PAYLOAD_SIZE)
			data_size -= DEFAULT_PAYLOAD_SIZE;
		else
			data_size = 0;

		_gnutls_buffer_reset(&session->internals.hb_local_data);

		ret =
		    _gnutls_buffer_resize(&session->internals.
					  hb_local_data, data_size);
		if (ret < 0)
			return gnutls_assert_val(ret);

		ret =
		    _gnutls_rnd(GNUTLS_RND_NONCE,
				session->internals.hb_local_data.data,
				data_size);
		if (ret < 0)
			return gnutls_assert_val(ret);

		gettime(&session->internals.hb_ping_start);
		session->internals.hb_local_data.length = data_size;
		session->internals.hb_state = SHB_SEND2;
	case SHB_SEND2:
		session->internals.hb_actual_retrans_timeout_ms =
		    session->internals.hb_retrans_timeout_ms;
	      retry:
		ret =
		    heartbeat_send_data(session,
					session->internals.hb_local_data.
					data,
					session->internals.hb_local_data.
					length, HEARTBEAT_REQUEST);
		if (ret < 0)
			return gnutls_assert_val(ret);

		gettime(&session->internals.hb_ping_sent);

		if (!(flags & GNUTLS_HEARTBEAT_WAIT)) {
			session->internals.hb_state = SHB_SEND1;
			break;
		}

		session->internals.hb_state = SHB_RECV;

	case SHB_RECV:
		ret =
		    _gnutls_recv_int(session, GNUTLS_HEARTBEAT, -1, NULL,
				     0, NULL,
				     session->internals.
				     hb_actual_retrans_timeout_ms);
		if (ret == GNUTLS_E_HEARTBEAT_PONG_RECEIVED) {
			session->internals.hb_state = SHB_SEND1;
			break;
		} else if (ret == GNUTLS_E_TIMEDOUT) {
			retries++;
			if (max_tries > 0 && retries > max_tries) {
				session->internals.hb_state = SHB_SEND1;
				return gnutls_assert_val(ret);
			}

			gettime(&now);
			diff =
			    timespec_sub_ms(&now,
					    &session->internals.
					    hb_ping_start);
			if (diff > session->internals.hb_total_timeout_ms) {
				session->internals.hb_state = SHB_SEND1;
				return
				    gnutls_assert_val(GNUTLS_E_TIMEDOUT);
			}

			session->internals.hb_actual_retrans_timeout_ms *=
			    2;
			session->internals.hb_actual_retrans_timeout_ms %=
			    MAX_DTLS_TIMEOUT;

			session->internals.hb_state = SHB_SEND2;
			goto retry;
		} else if (ret < 0) {
			session->internals.hb_state = SHB_SEND1;
			return gnutls_assert_val(ret);
		}
	}

	return 0;
}
Example #10
0
/* This function behaves exactly like write(). The only difference is
 * that it accepts, the gnutls_session_t and the content_type_t of data to
 * send (if called by the user the Content is specific)
 * It is intended to transfer data, under the current session.    
 *
 * Oct 30 2001: Removed capability to send data more than MAX_RECORD_SIZE.
 * This makes the function much easier to read, and more error resistant
 * (there were cases were the old function could mess everything up).
 * --nmav
 *
 * This function may accept a NULL pointer for data, and 0 for size, if
 * and only if the previous send was interrupted for some reason.
 *
 */
ssize_t
_gnutls_send_int (gnutls_session_t session, content_type_t type,
		  gnutls_handshake_description_t htype, const void *_data,
		  size_t sizeofdata)
{
  uint8_t *cipher;
  int cipher_size;
  int retval, ret;
  int data2send_size;
  uint8_t headers[5];
  const uint8_t *data = _data;
  int erecord_size = 0;
  opaque *erecord = NULL;

  /* Do not allow null pointer if the send buffer is empty.
   * If the previous send was interrupted then a null pointer is
   * ok, and means to resume.
   */
  if (session->internals.record_send_buffer.length == 0 &&
      (sizeofdata == 0 && _data == NULL))
    {
      gnutls_assert ();
      return GNUTLS_E_INVALID_REQUEST;
    }

  if (type != GNUTLS_ALERT)	/* alert messages are sent anyway */
    if (session_is_valid (session) || session->internals.may_not_write != 0)
      {
	gnutls_assert ();
	return GNUTLS_E_INVALID_SESSION;
      }



  headers[0] = type;

  /* Use the default record version, if it is
   * set.
   */
  copy_record_version (session, htype, &headers[1]);


  _gnutls_record_log
    ("REC[%x]: Sending Packet[%d] %s(%d) with length: %d\n", session,
     (int) _gnutls_uint64touint32 (&session->connection_state.
				   write_sequence_number),
     _gnutls_packet2str (type), type, sizeofdata);

  if (sizeofdata > MAX_RECORD_SEND_SIZE)
    data2send_size = MAX_RECORD_SEND_SIZE;
  else
    data2send_size = sizeofdata;

  /* Only encrypt if we don't have data to send 
   * from the previous run. - probably interrupted.
   */
  if (session->internals.record_send_buffer.length > 0)
    {
      ret = _gnutls_io_write_flush (session);
      if (ret > 0)
	cipher_size = ret;
      else
	cipher_size = 0;

      cipher = NULL;

      retval = session->internals.record_send_buffer_user_size;
    }
  else
    {

      /* now proceed to packet encryption
       */
      cipher_size = data2send_size + MAX_RECORD_OVERHEAD;
      cipher = gnutls_malloc (cipher_size);
      if (cipher == NULL)
	{
	  gnutls_assert ();
	  return GNUTLS_E_MEMORY_ERROR;
	}

      cipher_size =
	_gnutls_encrypt (session, headers, RECORD_HEADER_SIZE, data,
			 data2send_size, cipher, cipher_size, type, 1);
      if (cipher_size <= 0)
	{
	  gnutls_assert ();
	  if (cipher_size == 0)
	    cipher_size = GNUTLS_E_ENCRYPTION_FAILED;
	  gnutls_afree (erecord);
	  gnutls_free (cipher);
	  return cipher_size;	/* error */
	}

      retval = data2send_size;
      session->internals.record_send_buffer_user_size = data2send_size;

      /* increase sequence number
       */
      if (_gnutls_uint64pp
	  (&session->connection_state.write_sequence_number) != 0)
	{
	  session_invalidate (session);
	  gnutls_assert ();
	  gnutls_afree (erecord);
	  gnutls_free (cipher);
	  return GNUTLS_E_RECORD_LIMIT_REACHED;
	}

      ret =
	_gnutls_io_write_buffered2 (session, erecord, erecord_size,
				    cipher, cipher_size);
      gnutls_afree (erecord);
      gnutls_free (cipher);
    }

  if (ret != cipher_size + erecord_size)
    {
      if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
	{
	  /* If we have sent any data then just return
	   * the error value. Do not invalidate the session.
	   */
	  gnutls_assert ();
	  return ret;
	}

      if (ret > 0)
	{
	  gnutls_assert ();
	  ret = GNUTLS_E_INTERNAL_ERROR;
	}
      session_unresumable (session);
      session->internals.may_not_write = 1;
      gnutls_assert ();
      return ret;
    }

  session->internals.record_send_buffer_user_size = 0;

  _gnutls_record_log ("REC[%x]: Sent Packet[%d] %s(%d) with length: %d\n",
		      session,
		      (int) _gnutls_uint64touint32 (&session->
						    connection_state.
						    write_sequence_number),
		      _gnutls_packet2str (type), type, cipher_size);

  return retval;
}