Example #1
0
ci_inline void ci_tcp_set_addr_on_promote(ci_netif* netif, ci_tcp_state* ts,
                                          ci_tcp_state_synrecv* tsr,
                                          ci_tcp_socket_listen* tls)
{
  /* copy and initialise state */
  ts->s.pkt.ip.ip_saddr_be32 = tsr->l_addr;
  TS_TCP(ts)->tcp_source_be16 = sock_lport_be16(&tls->s);
  ts->s.cp.ip_laddr_be32 = tsr->l_addr;
  ts->s.cp.lport_be16 = sock_lport_be16(&tls->s);
  ci_tcp_set_peer(ts, tsr->r_addr, tsr->r_port);

  /* "filter" equivalent for loopback socket */
  if( OO_SP_NOT_NULL(tsr->local_peer) ) {
    ci_tcp_state *peer = ID_TO_TCP(netif, tsr->local_peer);
    ts->local_peer = tsr->local_peer;
    peer->local_peer = S_SP(ts);
  }
}
Example #2
0
static int ci_tcp_connect_ul_start(ci_netif *ni, ci_tcp_state* ts,
				   ci_uint32 dst_be32, unsigned dport_be16,
                                   int* fail_rc)
{
  ci_ip_pkt_fmt* pkt;
  int rc = 0;

  ci_assert(ts->s.pkt.mtu);

  /* Now that we know the outgoing route, set the MTU related values.
   * Note, even these values are speculative since the real MTU
   * could change between now and passing the packet to the lower layers
   */
  ts->amss = ts->s.pkt.mtu - sizeof(ci_tcp_hdr) - sizeof(ci_ip4_hdr);
#if CI_CFG_LIMIT_AMSS
  ts->amss = ci_tcp_limit_mss(ts->amss, ni, __FUNCTION__);
#endif

  /* Default smss until discovered by MSS option in SYN - RFC1122 4.2.2.6 */
  ts->smss = CI_CFG_TCP_DEFAULT_MSS;

  /* set pmtu, eff_mss, snd_buf and adjust windows */
  ci_pmtu_set(ni, &ts->pmtus, ts->s.pkt.mtu);
  ci_tcp_set_eff_mss(ni, ts);
  ci_tcp_set_initialcwnd(ni, ts);

  /* Send buffer adjusted by ci_tcp_set_eff_mss(), but we want it to stay
   * zero until the connection is established.
   */
  ts->so_sndbuf_pkts = 0;

  /* 
   * 3. State and address are OK. It's address routed through our NIC.
   *    Do connect().
   */
  ci_assert_nequal(ts->s.pkt.ip.ip_saddr_be32, INADDR_ANY);

  if( ts->s.s_flags & CI_SOCK_FLAG_CONNECT_MUST_BIND ) {
    ci_sock_cmn* s = &ts->s;
    ci_uint16 source_be16 = 0;

    if( s->s_flags & CI_SOCK_FLAG_ADDR_BOUND )
      rc = __ci_bind(ni, &ts->s, ts->s.pkt.ip.ip_saddr_be32, &source_be16);
    else 
      rc = __ci_bind(ni, &ts->s, INADDR_ANY, &source_be16);
    if(CI_LIKELY( rc == 0 )) {
      TS_TCP(ts)->tcp_source_be16 = source_be16;
      ts->s.cp.lport_be16 = source_be16;
      LOG_TC(log(LNT_FMT "connect: our bind returned %s:%u", 
                 LNT_PRI_ARGS(ni, ts),
                 ip_addr_str(INADDR_ANY),
                 (unsigned) CI_BSWAP_BE16(TS_TCP(ts)->tcp_source_be16)));
    }
    else {
      LOG_U(ci_log("__ci_bind returned %d at %s:%d", CI_GET_ERROR(rc),
                   __FILE__, __LINE__));
      *fail_rc = rc;
      return CI_CONNECT_UL_FAIL;
    }
    if(CI_UNLIKELY( ts->s.pkt.ip.ip_saddr_be32 == 0 )) {
      CI_SET_ERROR(*fail_rc, EINVAL);
      return CI_CONNECT_UL_FAIL;
    }
  }

  ci_tcp_set_peer(ts, dst_be32, dport_be16);

  /* Make sure we can get a buffer before we change state. */
  pkt = ci_netif_pkt_tx_tcp_alloc(ni);
  if( CI_UNLIKELY(! pkt) ) {
    /* NB. We've already done a poll above. */
    rc = ci_netif_pkt_wait(ni, &ts->s, CI_SLEEP_NETIF_LOCKED|CI_SLEEP_NETIF_RQ);
    if( ci_netif_pkt_wait_was_interrupted(rc) ) {
      CI_SET_ERROR(*fail_rc, -rc);
      return CI_CONNECT_UL_LOCK_DROPPED;
    }
    /* OK, there are (probably) packets available - go try again.  Note we
     * jump back to the top of the function because someone may have
     * connected this socket in the mean-time, so we need to check the
     * state once more.
     */
    return CI_CONNECT_UL_START_AGAIN;
  }

#ifdef ONLOAD_OFE
    if( ni->ofe != NULL )
      ts->s.ofe_code_start = ofe_socktbl_find(
                        ni->ofe, OFE_SOCKTYPE_TCP_ACTIVE,
                        tcp_laddr_be32(ts), tcp_raddr_be32(ts),
                        tcp_lport_be16(ts), tcp_rport_be16(ts));
#endif

  rc = ci_tcp_ep_set_filters(ni, S_SP(ts), ts->s.cp.so_bindtodevice,
                             OO_SP_NULL);
  if( rc < 0 ) {
    /* Perhaps we've run out of filters?  See if we can push a socket out
     * of timewait and steal its filter.
     */
    ci_assert_nequal(rc, -EFILTERSSOME);
    if( rc != -EBUSY || ! ci_netif_timewait_try_to_free_filter(ni) ||
        (rc = ci_tcp_ep_set_filters(ni, S_SP(ts),
                                    ts->s.cp.so_bindtodevice,
                                    OO_SP_NULL)) < 0 ) {
      ci_assert_nequal(rc, -EFILTERSSOME);
      /* Either a different error, or our efforts to free a filter did not
       * work.
       */
      if( ! (ts->s.s_flags & CI_SOCK_FLAG_ADDR_BOUND) ) {
        ts->s.pkt.ip.ip_saddr_be32 = 0;
        ts->s.cp.ip_laddr_be32 = 0;
      }
      ci_netif_pkt_release(ni, pkt);
      CI_SET_ERROR(*fail_rc, -rc);
      return CI_CONNECT_UL_FAIL;
    }
  }

  LOG_TC(log(LNT_FMT "CONNECT %s:%u->%s:%u", LNT_PRI_ARGS(ni, ts),
	     ip_addr_str(ts->s.pkt.ip.ip_saddr_be32),
	     (unsigned) CI_BSWAP_BE16(TS_TCP(ts)->tcp_source_be16),
	     ip_addr_str(ts->s.pkt.ip.ip_daddr_be32),
	     (unsigned) CI_BSWAP_BE16(TS_TCP(ts)->tcp_dest_be16)));

  /* We are going to send the SYN - set states appropriately */
  tcp_snd_una(ts) = tcp_snd_nxt(ts) = tcp_enq_nxt(ts) = tcp_snd_up(ts) =
    ci_tcp_initial_seqno(ni);
  ts->snd_max = tcp_snd_nxt(ts) + 1;

  /* Must be after initialising snd_una. */
  ci_tcp_clear_rtt_timing(ts);
  ci_tcp_set_flags(ts, CI_TCP_FLAG_SYN);
  ts->tcpflags &=~ CI_TCPT_FLAG_OPT_MASK;
  ts->tcpflags |= NI_OPTS(ni).syn_opts;

  if( (ts->tcpflags & CI_TCPT_FLAG_WSCL) ) {
    ts->rcv_wscl = ci_tcp_wscl_by_buff(ni, ci_tcp_rcvbuf_established(ni, &ts->s));
    CI_IP_SOCK_STATS_VAL_RXWSCL(ts, ts->rcv_wscl);
  }
  else {
    ts->rcv_wscl = 0;
    CI_IP_SOCK_STATS_VAL_RXWSCL(ts, 0);
  }
  ci_tcp_set_rcvbuf(ni, ts);
  ci_tcp_init_rcv_wnd(ts, "CONNECT");

  /* outgoing_hdrs_len is initialised to include timestamp option. */
  if( ! (ts->tcpflags & CI_TCPT_FLAG_TSO) )
    ts->outgoing_hdrs_len = sizeof(ci_ip4_hdr)+sizeof(ci_tcp_hdr);
  if( ci_tcp_can_stripe(ni, ts->s.pkt.ip.ip_saddr_be32,
			ts->s.pkt.ip.ip_daddr_be32) )
    ts->tcpflags |= CI_TCPT_FLAG_STRIPE;
  ci_tcp_set_slow_state(ni, ts, CI_TCP_SYN_SENT);

  /* If the app trys to send data on a socket in SYN_SENT state
  ** then the data is queued for send until the SYN gets ACKed.
  ** (rfc793 p56)
  **
  ** Receive calls on the socket should block until data arrives
  ** (rfc793 p58)
  **
  ** Clearing tx_errno and rx_errno acheive this. The transmit window
  ** is set to 1 byte which ensures that only the SYN packet gets
  ** sent until the ACK is received with more window. 
  */
  ci_assert(ts->snd_max == tcp_snd_nxt(ts) + 1);
  ts->s.rx_errno = 0;
  ts->s.tx_errno = 0; 
  ci_tcp_enqueue_no_data(ts, ni, pkt);
  ci_tcp_set_flags(ts, CI_TCP_FLAG_ACK);  

  if( ts->s.b.sb_aflags & (CI_SB_AFLAG_O_NONBLOCK | CI_SB_AFLAG_O_NDELAY) ) {
    ts->tcpflags |= CI_TCPT_FLAG_NONBLOCK_CONNECT;
    LOG_TC(log( LNT_FMT "Non-blocking connect - return EINPROGRESS",
		LNT_PRI_ARGS(ni, ts)));
    CI_SET_ERROR(*fail_rc, EINPROGRESS);
    return CI_CONNECT_UL_FAIL;
  }

  return CI_CONNECT_UL_OK;
}
Example #3
0
/* c_ni is assumed to be locked on enterance and is always unlocked on
 * exit. */
int ci_tcp_connect_lo_toconn(ci_netif *c_ni, oo_sp c_id, ci_uint32 dst,
                             ci_netif *l_ni, oo_sp l_id)
{
  ci_tcp_state *ts;
  ci_tcp_socket_listen *tls, *alien_tls;
  citp_waitable_obj *wo;
  citp_waitable *w;
  int rc;

  ci_assert(ci_netif_is_locked(c_ni));
  ci_assert(OO_SP_NOT_NULL(c_id));
  ci_assert(OO_SP_NOT_NULL(l_id));

  LOG_TC(log("%s: connect %d:%d to %d:%d", __FUNCTION__,
             c_ni->state->stack_id, OO_SP_TO_INT(c_id),
             l_ni->state->stack_id, OO_SP_TO_INT(l_id)));

  alien_tls = SP_TO_TCP_LISTEN(l_ni, l_id);
  if( (int)ci_tcp_acceptq_n(alien_tls) >= alien_tls->acceptq_max ) {
    ci_netif_unlock(c_ni);
    return -EBUSY;
  }

  /* In c_ni, create shadow listening socket tls (copy l_id) */
  ts = ci_tcp_get_state_buf(c_ni);
  if( ts == NULL ) {
    ci_netif_unlock(c_ni);
    LOG_E(ci_log("%s: [%d] out of socket buffers", __FUNCTION__, NI_ID(c_ni)));
    return -ENOMEM;
  }

  /* init common tcp fields */
  ts->s.so = alien_tls->s.so;
  ts->s.cp.ip_ttl = alien_tls->s.cp.ip_ttl;
  S_TCP_HDR(&ts->s)->tcp_source_be16 =
      S_TCP_HDR(&alien_tls->s)->tcp_source_be16;
  ts->s.domain = alien_tls->s.domain;
  ts->c = alien_tls->c;
  ts->c.tcp_defer_accept = OO_TCP_DEFER_ACCEPT_OFF;

  /* make sure nobody will ever connect to our "shadow" socket
   * except us */
  ci_bit_set(&ts->s.b.sb_aflags, CI_SB_AFLAG_ORPHAN_BIT);

  ci_tcp_set_slow_state(c_ni, ts, CI_TCP_LISTEN);
  tls = SOCK_TO_TCP_LISTEN(&ts->s);
  /* no timer: */
  tls->s.s_flags = alien_tls->s.s_flags | CI_SOCK_FLAG_BOUND_ALIEN;

  tls->acceptq_max = 1;
  rc = ci_tcp_listen_init(c_ni, tls);
  if( rc != 0 ) {
    citp_waitable_obj_free(c_ni, &tls->s.b);
    return rc;
  }

  /* Connect c_id to tls */
  ts = SP_TO_TCP(c_ni, c_id);
  rc = ci_tcp_connect_lo_samestack(c_ni, ts, tls->s.b.bufid);

  /* Accept as from tls */
  if( !ci_tcp_acceptq_not_empty(tls) ) {
    /* it is possible, for example, if ci_tcp_listenq_try_promote() failed
     * because there are no endpoints */
    ci_tcp_listenq_drop_all(c_ni, tls);
    citp_waitable_obj_free(c_ni, &tls->s.b);
    ci_netif_unlock(c_ni);
    return -EBUSY;
  }
  w = ci_tcp_acceptq_get(c_ni, tls);
  ci_assert(w);
  LOG_TV(ci_log("%s: %d:%d to %d:%d shadow %d:%d accepted %d:%d",
                __FUNCTION__,
                c_ni->state->stack_id, OO_SP_TO_INT(c_id),
                l_ni->state->stack_id, OO_SP_TO_INT(l_id),
                c_ni->state->stack_id, tls->s.b.bufid,
                c_ni->state->stack_id, w->bufid));

  ci_assert(w->state & CI_TCP_STATE_TCP);
  ci_assert(w->state != CI_TCP_LISTEN);

  /* Destroy tls.
   * NB: nobody could possibly connect to it, so no need to do proper
   * shutdown.
   */
  ci_assert_equal(ci_tcp_acceptq_n(tls), 0);
  ci_tcp_listenq_drop_all(c_ni, tls);
  citp_waitable_obj_free(c_ni, &tls->s.b);
  ci_netif_unlock(c_ni);

  /* Keep a port reference */
  {
    tcp_helper_endpoint_t *l_ep, *a_ep;
    struct oo_file_ref* os_sock_ref;
    ci_irqlock_state_t lock_flags;

    l_ep = ci_trs_ep_get(netif2tcp_helper_resource(l_ni), l_id);
    a_ep = ci_trs_ep_get(netif2tcp_helper_resource(c_ni), W_SP(w));
    ci_irqlock_lock(&l_ep->thr->lock, &lock_flags);
    os_sock_ref = l_ep->os_socket;
    ci_assert_equal(a_ep->os_port_keeper, NULL);
    if( os_sock_ref != NULL ) {
      os_sock_ref = oo_file_ref_add(os_sock_ref);
      os_sock_ref = oo_file_ref_xchg(&a_ep->os_port_keeper, os_sock_ref);
      ci_irqlock_unlock(&l_ep->thr->lock, &lock_flags);
      if( os_sock_ref != NULL )
        oo_file_ref_drop(os_sock_ref);
    }
    else {
      ci_irqlock_unlock(&l_ep->thr->lock, &lock_flags);
      goto cleanup;
    }
  }

  /* lock l_ni: Check that l_id is the same socket it used to be */
  /* create ref-sock in l_ni, put it into acc q */
  if( ci_netif_lock(l_ni) != 0 )
    goto cleanup;
  if( alien_tls->s.b.state != CI_TCP_LISTEN ||
      (alien_tls->s.b.sb_aflags & CI_SB_AFLAG_ORPHAN) ||
      S_TCP_HDR(&alien_tls->s)->tcp_source_be16 != TS_TCP(ts)->tcp_dest_be16 ||
      (alien_tls->s.pkt.ip.ip_saddr_be32 != INADDR_ANY &&
       alien_tls->s.pkt.ip.ip_saddr_be32 != ts->s.pkt.ip.ip_daddr_be32) ) {
    ci_netif_unlock(l_ni);
    goto cleanup;
  }

  ci_bit_mask_set(&w->sb_aflags,
                  CI_SB_AFLAG_TCP_IN_ACCEPTQ | CI_SB_AFLAG_ORPHAN);

  wo = citp_waitable_obj_alloc(l_ni);
  if( wo == NULL ) {
    ci_netif_unlock(l_ni);
    goto cleanup;
  }
  wo->waitable.state = CI_TCP_CLOSED;
  wo->waitable.sb_aflags |= CI_SB_AFLAG_MOVED_AWAY;
  wo->waitable.moved_to_stack_id = c_ni->state->stack_id;
  wo->waitable.moved_to_sock_id = W_SP(w);
  LOG_TC(log("%s: put to acceptq %d:%d referencing %d:%d", __func__,
             l_ni->state->stack_id, OO_SP_TO_INT(W_SP(&wo->waitable)),
             c_ni->state->stack_id, OO_SP_TO_INT(W_SP(w))));

  ci_tcp_acceptq_put(l_ni, alien_tls, &wo->waitable);
  citp_waitable_wake_not_in_poll(l_ni, &alien_tls->s.b, CI_SB_FLAG_WAKE_RX);
  ci_netif_unlock(l_ni);

  return rc;

cleanup:
  ci_assert(w->sb_aflags & CI_SB_AFLAG_ORPHAN);
  ci_bit_mask_clear(&w->sb_aflags,
                    CI_SB_AFLAG_TCP_IN_ACCEPTQ | CI_SB_AFLAG_ORPHAN);
  efab_tcp_helper_close_endpoint(netif2tcp_helper_resource(c_ni), w->bufid);
  /* we can not guarantee c_ni lock, so we can' call
   * ci_tcp_drop(c_ni, ts).  So, we return error; UL will handover
   * and close ts endpoint. */
  return -EBUSY;
}
Example #4
0
int ci_tcp_listen(citp_socket* ep, ci_fd_t fd, int backlog)
{
  /* 
  ** ?? error handling on possible fails not handled robustly...
  ** ?? Need to check port number is valid TODO
  */

  /*! \todo If not bound then we have to be listening on all interfaces.
   * It's likely that we won't be coming through here as we have to
   * listen on the OS socket too! */
  ci_tcp_state* ts;
  ci_tcp_socket_listen* tls;
  ci_netif* netif = ep->netif;
  ci_sock_cmn* s = ep->s;
  unsigned ul_backlog = backlog;
  int rc;
  oo_p sp;

  LOG_TC(log("%s "SK_FMT" listen backlog=%d", __FUNCTION__, SK_PRI_ARGS(ep), 
             backlog));
  CHECK_TEP(ep);

  if( NI_OPTS(netif).tcp_listen_handover )
    return CI_SOCKET_HANDOVER;
  if( !NI_OPTS(netif).tcp_server_loopback) {
    /* We should handover if the socket is bound to alien address. */
    if( s->s_flags & CI_SOCK_FLAG_BOUND_ALIEN )
      return CI_SOCKET_HANDOVER;
  }

  if( ul_backlog < 0 )
    ul_backlog = NI_OPTS(netif).max_ep_bufs;
  else if( ul_backlog < NI_OPTS(netif).acceptq_min_backlog )
    ul_backlog = NI_OPTS(netif).acceptq_min_backlog;

  if( s->b.state == CI_TCP_LISTEN ) {
    tls = SOCK_TO_TCP_LISTEN(s);
    tls->acceptq_max = ul_backlog;
    ci_tcp_helper_listen_os_sock(fd, ul_backlog);
    return 0;
  }

  if( s->b.state != CI_TCP_CLOSED ) {
    CI_SET_ERROR(rc, EINVAL);
    return rc;
  }


  ts = SOCK_TO_TCP(s);

  /* Bug 3376: if socket used for a previous, failed, connect then the error
   * numbers will not be as expected.  Only seen when not using listening
   * netifs (as moving the EP to the new netif resets them). 
   */

  ts->s.tx_errno = EPIPE;



  ts->s.rx_errno = ENOTCONN;

  /* fill in address/ports and all TCP state */
  if( !(ts->s.s_flags & CI_SOCK_FLAG_BOUND) ) {
    ci_uint16 source_be16;

    /* They haven't previously done a bind, so we need to choose 
     * a port.  As we haven't been given a hint we let the OS choose. */

    source_be16 = 0;
    rc = __ci_bind(ep->netif, ep->s, ts->s.pkt.ip.ip_saddr_be32, &source_be16);
    if (CI_LIKELY( rc==0 )) {
      TS_TCP(ts)->tcp_source_be16 = source_be16;
      ts->s.cp.lport_be16 = source_be16;
      LOG_TC(log(LNT_FMT "listen: our bind returned %s:%u", 
                 LNT_PRI_ARGS(ep->netif, ts),
                 ip_addr_str(ts->s.pkt.ip.ip_saddr_be32),
                 (unsigned) CI_BSWAP_BE16(TS_TCP(ts)->tcp_source_be16)));

    } else {
      LOG_U(ci_log("__ci_bind returned %d at %s:%d", CI_GET_ERROR(rc),
                   __FILE__, __LINE__));
      return rc;
    }
  } 

  ci_sock_lock(netif, &ts->s.b);
  ci_tcp_set_slow_state(netif, ts, CI_TCP_LISTEN);
  tls = SOCK_TO_TCP_LISTEN(&ts->s);

  tcp_raddr_be32(tls) = 0u;
  tcp_rport_be16(tls) = 0u;

  ci_assert_equal(tls->s.tx_errno, EPIPE);



  ci_assert_equal(tls->s.rx_errno, ENOTCONN);

  /* setup listen timer - do it before the first return statement,
   * because __ci_tcp_listen_to_normal() will be called on error path. */
  if( ~tls->s.s_flags & CI_SOCK_FLAG_BOUND_ALIEN ) {
    sp = TS_OFF(netif, tls);
    OO_P_ADD(sp, CI_MEMBER_OFFSET(ci_tcp_socket_listen, listenq_tid));
    ci_ip_timer_init(netif, &tls->listenq_tid, sp, "lstq");
    tls->listenq_tid.param1 = S_SP(tls);
    tls->listenq_tid.fn = CI_IP_TIMER_TCP_LISTEN;
  }

  rc = ci_tcp_listen_init(netif, tls);
  ci_sock_unlock(netif, &ts->s.b);
  if( rc != 0 ) {
    CI_SET_ERROR(rc, -rc);
    goto listen_fail;
  }
  tls->acceptq_max = ul_backlog;

  CITP_STATS_TCP_LISTEN(CI_ZERO(&tls->stats));

  /* install all the filters needed for this connection 
   *    - tcp_laddr_be32(ts) = 0 for IPADDR_ANY
   *
   *  TODO: handle BINDTODEVICE by setting phys_port paramter to correct 
   *        physical L5 port index
   *  TODO: handle REUSEADDR by setting last paramter to TRUE
   */
  if( ~s->s_flags & CI_SOCK_FLAG_BOUND_ALIEN ) {
#ifdef ONLOAD_OFE
    if( netif->ofe != NULL ) {
      tls->s.ofe_code_start = ofe_socktbl_find(
                        netif->ofe, OFE_SOCKTYPE_TCP_LISTEN,
                        tcp_laddr_be32(tls), INADDR_ANY,
                        tcp_lport_be16(ts), 0);
      tls->ofe_promote = ofe_socktbl_find(
                        netif->ofe, OFE_SOCKTYPE_TCP_PASSIVE,
                        tcp_laddr_be32(tls), INADDR_ANY,
                        tcp_lport_be16(ts), 0);
    }
#endif
    rc = ci_tcp_ep_set_filters(netif, S_SP(tls), tls->s.cp.so_bindtodevice,
                               OO_SP_NULL);
    if( rc == -EFILTERSSOME ) {
      if( CITP_OPTS.no_fail )
        rc = 0;
      else {
        ci_tcp_ep_clear_filters(netif, S_SP(tls), 0);
        rc = -ENOBUFS;
      }
    }
    ci_assert_nequal(rc, -EFILTERSSOME);
    VERB(ci_log("%s: set_filters  returned %d", __FUNCTION__, rc));
    if (rc < 0) {
      CI_SET_ERROR(rc, -rc);
      goto post_listen_fail;
    }
  }


  /* 
   * Call of system listen() is required for listen any, local host
   * communications server and multi-homed server (to accept connections
   * to L5 assigned address(es), but incoming from other interfaces).
   */
#ifdef __ci_driver__
  {
    rc = efab_tcp_helper_listen_os_sock( netif2tcp_helper_resource(netif),
					 S_SP(tls), backlog);
  }
#else
  rc = ci_tcp_helper_listen_os_sock(fd, backlog);
#endif
  if ( rc < 0 ) {
    /* clear the filter we've just set */
    ci_tcp_ep_clear_filters(netif, S_SP(tls), 0);
    goto post_listen_fail;
  }
  return 0;

 post_listen_fail:
  ci_tcp_listenq_drop_all(netif, tls);
 listen_fail:
  /* revert TCP state to a non-listening socket format */
  __ci_tcp_listen_to_normal(netif, tls);
  /* Above function sets orphan flag but we are attached to an FD. */
  ci_bit_clear(&tls->s.b.sb_aflags, CI_SB_AFLAG_ORPHAN_BIT);
#ifdef __ci_driver__
  return rc;
#else
  return CI_SOCKET_ERROR;
#endif
}