2 * Copyright (c) 2016 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vnet/tcp/tcp.h>
17 #include <vnet/session/session.h>
18 #include <vnet/fib/fib.h>
19 #include <vnet/dpo/load_balance.h>
25 tcp_connection_bind (u32 session_index, ip46_address_t * ip,
26 u16 port_host_byte_order, u8 is_ip4)
28 tcp_main_t *tm = &tcp_main;
29 tcp_connection_t *listener;
31 pool_get (tm->listener_pool, listener);
32 memset (listener, 0, sizeof (*listener));
34 listener->c_c_index = listener - tm->listener_pool;
35 listener->c_lcl_port = clib_host_to_net_u16 (port_host_byte_order);
39 listener->c_lcl_ip4.as_u32 = ip->ip4.as_u32;
40 listener->c_is_ip4 = 1;
41 listener->c_proto = SESSION_TYPE_IP4_TCP;
45 clib_memcpy (&listener->c_lcl_ip6, &ip->ip6, sizeof (ip6_address_t));
46 listener->c_proto = SESSION_TYPE_IP6_TCP;
49 listener->c_s_index = session_index;
50 listener->state = TCP_STATE_LISTEN;
52 tcp_connection_timers_init (listener);
54 TCP_EVT_DBG (TCP_EVT_BIND, listener);
56 return listener->c_c_index;
60 tcp_session_bind_ip4 (u32 session_index, ip46_address_t * ip,
61 u16 port_host_byte_order)
63 return tcp_connection_bind (session_index, ip, port_host_byte_order, 1);
67 tcp_session_bind_ip6 (u32 session_index, ip46_address_t * ip,
68 u16 port_host_byte_order)
70 return tcp_connection_bind (session_index, ip, port_host_byte_order, 0);
74 tcp_connection_unbind (u32 listener_index)
76 tcp_main_t *tm = vnet_get_tcp_main ();
77 TCP_EVT_DBG (TCP_EVT_UNBIND,
78 pool_elt_at_index (tm->listener_pool, listener_index));
79 pool_put_index (tm->listener_pool, listener_index);
83 tcp_session_unbind (u32 listener_index)
85 tcp_connection_unbind (listener_index);
89 transport_connection_t *
90 tcp_session_get_listener (u32 listener_index)
92 tcp_main_t *tm = vnet_get_tcp_main ();
94 tc = pool_elt_at_index (tm->listener_pool, listener_index);
95 return &tc->connection;
99 * Cleans up connection state.
104 tcp_connection_cleanup (tcp_connection_t * tc)
106 tcp_main_t *tm = &tcp_main;
108 transport_endpoint_t *tep;
110 /* Cleanup local endpoint if this was an active connect */
111 tepi = transport_endpoint_lookup (&tm->local_endpoints_table, &tc->c_lcl_ip,
115 if (tepi != TRANSPORT_ENDPOINT_INVALID_INDEX)
117 tep = pool_elt_at_index (tm->local_endpoints, tepi);
118 transport_endpoint_table_del (&tm->local_endpoints_table, tep);
119 pool_put (tm->local_endpoints, tep);
122 /* Make sure all timers are cleared */
123 tcp_connection_timers_reset (tc);
125 /* Check if half-open */
126 if (tc->state == TCP_STATE_SYN_SENT)
127 pool_put (tm->half_open_connections, tc);
129 pool_put (tm->connections[tc->c_thread_index], tc);
133 * Connection removal.
135 * This should be called only once connection enters CLOSED state. Note
136 * that it notifies the session of the removal event, so if the goal is to
137 * just remove the connection, call tcp_connection_cleanup instead.
140 tcp_connection_del (tcp_connection_t * tc)
142 TCP_EVT_DBG (TCP_EVT_DELETE, tc);
143 stream_session_delete_notify (&tc->connection);
144 tcp_connection_cleanup (tc);
147 /** Notify session that connection has been reset.
149 * Switch state to closed and wait for session to call cleanup.
152 tcp_connection_reset (tcp_connection_t * tc)
156 case TCP_STATE_SYN_RCVD:
157 /* Cleanup everything. App wasn't notified yet */
158 stream_session_delete_notify (&tc->connection);
159 tcp_connection_cleanup (tc);
161 case TCP_STATE_SYN_SENT:
162 case TCP_STATE_ESTABLISHED:
163 case TCP_STATE_CLOSE_WAIT:
164 case TCP_STATE_FIN_WAIT_1:
165 case TCP_STATE_FIN_WAIT_2:
166 case TCP_STATE_CLOSING:
167 tc->state = TCP_STATE_CLOSED;
169 /* Make sure all timers are cleared */
170 tcp_connection_timers_reset (tc);
172 stream_session_reset_notify (&tc->connection);
174 case TCP_STATE_CLOSED:
181 * Begin connection closing procedure.
183 * If at the end the connection is not in CLOSED state, it is not removed.
184 * Instead, we rely on on TCP to advance through state machine to either
185 * 1) LAST_ACK (passive close) whereby when the last ACK is received
186 * tcp_connection_del is called. This notifies session of the delete and
188 * 2) TIME_WAIT (active close) whereby after 2MSL the 2MSL timer triggers
189 * and cleanup is called.
191 * N.B. Half-close connections are not supported
194 tcp_connection_close (tcp_connection_t * tc)
196 TCP_EVT_DBG (TCP_EVT_CLOSE, tc);
198 /* Send FIN if needed */
199 if (tc->state == TCP_STATE_ESTABLISHED
200 || tc->state == TCP_STATE_SYN_RCVD || tc->state == TCP_STATE_CLOSE_WAIT)
204 if (tc->state == TCP_STATE_ESTABLISHED || tc->state == TCP_STATE_SYN_RCVD)
205 tc->state = TCP_STATE_FIN_WAIT_1;
206 else if (tc->state == TCP_STATE_SYN_SENT)
207 tc->state = TCP_STATE_CLOSED;
208 else if (tc->state == TCP_STATE_CLOSE_WAIT)
209 tc->state = TCP_STATE_LAST_ACK;
211 /* If in CLOSED and WAITCLOSE timer is not set, delete connection now */
212 if (tc->timers[TCP_TIMER_WAITCLOSE] == TCP_TIMER_HANDLE_INVALID
213 && tc->state == TCP_STATE_CLOSED)
214 tcp_connection_del (tc);
218 tcp_session_close (u32 conn_index, u32 thread_index)
220 tcp_connection_t *tc;
221 tc = tcp_connection_get (conn_index, thread_index);
222 tcp_connection_close (tc);
226 tcp_session_cleanup (u32 conn_index, u32 thread_index)
228 tcp_connection_t *tc;
229 tc = tcp_connection_get (conn_index, thread_index);
231 /* Wait for the session tx events to clear */
232 tc->state = TCP_STATE_CLOSED;
233 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
237 ip_interface_get_first_ip (u32 sw_if_index, u8 is_ip4)
239 ip_lookup_main_t *lm4 = &ip4_main.lookup_main;
240 ip_lookup_main_t *lm6 = &ip6_main.lookup_main;
241 ip_interface_address_t *ia = 0;
246 foreach_ip_interface_address (lm4, ia, sw_if_index, 1 /* unnumbered */ ,
248 return ip_interface_address_get_address (lm4, ia);
255 foreach_ip_interface_address (lm6, ia, sw_if_index, 1 /* unnumbered */ ,
257 return ip_interface_address_get_address (lm6, ia);
265 #define PORT_MASK ((1 << 16)- 1)
267 * Allocate local port and add if successful add entry to local endpoint
268 * table to mark the pair as used.
271 tcp_allocate_local_port (tcp_main_t * tm, ip46_address_t * ip)
273 transport_endpoint_t *tep;
275 u16 min = 1024, max = 65535; /* XXX configurable ? */
279 time_now = tcp_time_now ();
281 /* Start at random point or max */
282 pool_get (tm->local_endpoints, tep);
283 clib_memcpy (&tep->ip, ip, sizeof (*ip));
285 /* Search for first free slot */
286 for (; tries >= 0; tries--)
290 /* Find a port in the specified range */
293 port = random_u32 (&time_now) & PORT_MASK;
294 if (PREDICT_TRUE (port >= min && port < max))
301 tei = transport_endpoint_lookup (&tm->local_endpoints_table, &tep->ip,
303 /* If not found, we're done */
304 if (tei == TRANSPORT_ENDPOINT_INVALID_INDEX)
306 transport_endpoint_table_add (&tm->local_endpoints_table, tep,
307 tep - tm->local_endpoints);
312 pool_put (tm->local_endpoints, tep);
317 * Initialize all connection timers as invalid
320 tcp_connection_timers_init (tcp_connection_t * tc)
324 /* Set all to invalid */
325 for (i = 0; i < TCP_N_TIMERS; i++)
327 tc->timers[i] = TCP_TIMER_HANDLE_INVALID;
330 tc->rto = TCP_RTO_INIT;
334 * Stop all connection timers
337 tcp_connection_timers_reset (tcp_connection_t * tc)
340 for (i = 0; i < TCP_N_TIMERS; i++)
342 tcp_timer_reset (tc, i);
346 typedef struct ip4_tcp_hdr
352 typedef struct ip6_tcp_hdr
359 tcp_connection_select_lb_bucket (tcp_connection_t * tc, const dpo_id_t * dpo,
362 const dpo_id_t *choice;
366 lb = load_balance_get (dpo->dpoi_index);
370 memset (&hdr, 0, sizeof (hdr));
371 hdr.ip.protocol = IP_PROTOCOL_TCP;
372 hdr.ip.address_pair.src.as_u32 = tc->c_lcl_ip.ip4.as_u32;
373 hdr.ip.address_pair.dst.as_u32 = tc->c_rmt_ip.ip4.as_u32;
374 hdr.tcp.src_port = tc->c_lcl_port;
375 hdr.tcp.dst_port = tc->c_rmt_port;
376 hash = ip4_compute_flow_hash (&hdr.ip, lb->lb_hash_config);
381 memset (&hdr, 0, sizeof (hdr));
382 hdr.ip.protocol = IP_PROTOCOL_TCP;
383 clib_memcpy (&hdr.ip.src_address, &tc->c_lcl_ip.ip6,
384 sizeof (ip6_address_t));
385 clib_memcpy (&hdr.ip.dst_address, &tc->c_rmt_ip.ip6,
386 sizeof (ip6_address_t));
387 hdr.tcp.src_port = tc->c_lcl_port;
388 hdr.tcp.dst_port = tc->c_rmt_port;
389 hash = ip6_compute_flow_hash (&hdr.ip, lb->lb_hash_config);
391 choice = load_balance_get_bucket_i (lb, hash & lb->lb_n_buckets_minus_1);
392 dpo_copy (result, choice);
396 tcp_lookup_rmt_in_fib (tcp_connection_t * tc)
400 clib_memcpy (&prefix.fp_addr, &tc->c_rmt_ip, sizeof (prefix.fp_addr));
401 prefix.fp_proto = tc->c_is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
402 prefix.fp_len = tc->c_is_ip4 ? 32 : 128;
403 return fib_table_lookup (0, &prefix);
407 tcp_connection_stack_on_fib_entry (tcp_connection_t * tc)
409 dpo_id_t choice = DPO_INVALID;
410 u32 output_node_index;
413 fe = fib_entry_get (tc->c_rmt_fei);
414 if (fe->fe_lb.dpoi_type != DPO_LOAD_BALANCE)
417 tcp_connection_select_lb_bucket (tc, &fe->fe_lb, &choice);
420 tc->c_is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
421 dpo_stack_from_node (output_node_index, &tc->c_rmt_dpo, &choice);
425 /** Stack tcp connection on peer's fib entry.
427 * This ultimately populates the dpo the connection will use to send packets.
430 tcp_connection_fib_attach (tcp_connection_t * tc)
432 tc->c_rmt_fei = tcp_lookup_rmt_in_fib (tc);
434 ASSERT (tc->c_rmt_fei != FIB_NODE_INDEX_INVALID);
436 tcp_connection_stack_on_fib_entry (tc);
439 /** Initialize tcp connection variables
441 * Should be called after having received a msg from the peer, i.e., a SYN or
442 * a SYNACK, such that connection options have already been exchanged. */
444 tcp_connection_init_vars (tcp_connection_t * tc)
446 tcp_connection_timers_init (tc);
448 scoreboard_init (&tc->sack_sb);
450 tcp_connection_fib_attach (tc);
454 tcp_connection_open (ip46_address_t * rmt_addr, u16 rmt_port, u8 is_ip4)
456 tcp_main_t *tm = vnet_get_tcp_main ();
457 tcp_connection_t *tc;
459 fib_node_index_t fei;
461 ip46_address_t lcl_addr;
465 * Find the local address and allocate port
467 memset (&lcl_addr, 0, sizeof (lcl_addr));
469 /* Find a FIB path to the destination */
470 clib_memcpy (&prefix.fp_addr, rmt_addr, sizeof (*rmt_addr));
471 prefix.fp_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
472 prefix.fp_len = is_ip4 ? 32 : 128;
474 fei = fib_table_lookup (0, &prefix);
476 /* Couldn't find route to destination. Bail out. */
477 if (fei == FIB_NODE_INDEX_INVALID)
480 sw_if_index = fib_entry_get_resolving_interface (fei);
482 if (sw_if_index == (u32) ~ 0)
488 ip4 = ip_interface_get_first_ip (sw_if_index, 1);
489 lcl_addr.ip4.as_u32 = ip4->as_u32;
494 ip6 = ip_interface_get_first_ip (sw_if_index, 0);
495 clib_memcpy (&lcl_addr.ip6, ip6, sizeof (*ip6));
498 /* Allocate source port */
499 lcl_port = tcp_allocate_local_port (tm, &lcl_addr);
502 clib_warning ("Failed to allocate src port");
507 * Create connection and send SYN
510 pool_get (tm->half_open_connections, tc);
511 memset (tc, 0, sizeof (*tc));
513 clib_memcpy (&tc->c_rmt_ip, rmt_addr, sizeof (ip46_address_t));
514 clib_memcpy (&tc->c_lcl_ip, &lcl_addr, sizeof (ip46_address_t));
515 tc->c_rmt_port = clib_host_to_net_u16 (rmt_port);
516 tc->c_lcl_port = clib_host_to_net_u16 (lcl_port);
517 tc->c_c_index = tc - tm->half_open_connections;
518 tc->c_is_ip4 = is_ip4;
519 tc->c_proto = is_ip4 ? SESSION_TYPE_IP4_TCP : SESSION_TYPE_IP6_TCP;
521 /* The other connection vars will be initialized after SYN ACK */
522 tcp_connection_timers_init (tc);
526 tc->state = TCP_STATE_SYN_SENT;
528 TCP_EVT_DBG (TCP_EVT_OPEN, tc);
530 return tc->c_c_index;
534 tcp_session_open_ip4 (ip46_address_t * addr, u16 port)
536 return tcp_connection_open (addr, port, 1);
540 tcp_session_open_ip6 (ip46_address_t * addr, u16 port)
542 return tcp_connection_open (addr, port, 0);
545 const char *tcp_dbg_evt_str[] = {
546 #define _(sym, str) str,
551 const char *tcp_fsm_states[] = {
552 #define _(sym, str) str,
553 foreach_tcp_fsm_state
558 format_tcp_state (u8 * s, va_list * args)
560 u32 state = va_arg (*args, u32);
562 if (state < TCP_N_STATES)
563 s = format (s, "%s", tcp_fsm_states[state]);
565 s = format (s, "UNKNOWN (%d (0x%x))", state, state);
569 const char *tcp_conn_timers[] = {
570 #define _(sym, str) str,
576 format_tcp_timers (u8 * s, va_list * args)
578 tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
581 for (i = 0; i < TCP_N_TIMERS; i++)
582 if (tc->timers[i] != TCP_TIMER_HANDLE_INVALID)
586 for (i = 0; i < last; i++)
588 if (tc->timers[i] != TCP_TIMER_HANDLE_INVALID)
589 s = format (s, "%s,", tcp_conn_timers[i]);
593 s = format (s, "%s]", tcp_conn_timers[i]);
601 format_tcp_congestion_status (u8 * s, va_list * args)
603 tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
604 if (tcp_in_recovery (tc))
605 s = format (s, "recovery");
606 else if (tcp_in_fastrecovery (tc))
607 s = format (s, "fastrecovery");
609 s = format (s, "none");
614 format_tcp_vars (u8 * s, va_list * args)
616 tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
617 s = format (s, " snd_una %u snd_nxt %u snd_una_max %u\n",
618 tc->snd_una - tc->iss, tc->snd_nxt - tc->iss,
619 tc->snd_una_max - tc->iss);
620 s = format (s, " rcv_nxt %u rcv_las %u\n",
621 tc->rcv_nxt - tc->irs, tc->rcv_las - tc->irs);
622 s = format (s, " snd_wnd %u rcv_wnd %u snd_wl1 %u snd_wl2 %u\n",
623 tc->snd_wnd, tc->rcv_wnd, tc->snd_wl1 - tc->irs,
624 tc->snd_wl2 - tc->iss);
625 s = format (s, " flight size %u send space %u rcv_wnd_av %d\n",
626 tcp_flight_size (tc), tcp_available_snd_space (tc),
627 tcp_rcv_wnd_available (tc));
628 s = format (s, " cong %U ", format_tcp_congestion_status, tc);
629 s = format (s, "cwnd %u ssthresh %u rtx_bytes %u bytes_acked %u\n",
630 tc->cwnd, tc->ssthresh, tc->snd_rxt_bytes, tc->bytes_acked);
631 s = format (s, " prev_ssthresh %u snd_congestion %u dupack %u\n",
632 tc->prev_ssthresh, tc->snd_congestion - tc->iss,
634 s = format (s, " rto %u rto_boff %u srtt %u rttvar %u rtt_ts %u ", tc->rto,
635 tc->rto_boff, tc->srtt, tc->rttvar, tc->rtt_ts);
636 s = format (s, "rtt_seq %u\n", tc->rtt_seq);
637 s = format (s, " scoreboard: %U\n", format_tcp_scoreboard, &tc->sack_sb);
638 if (vec_len (tc->snd_sacks))
639 s = format (s, " sacks tx: %U\n", format_tcp_sacks, tc);
645 format_tcp_connection_id (u8 * s, va_list * args)
647 tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
652 s = format (s, "[#%d][%s] %U:%d->%U:%d", tc->c_thread_index, "T",
653 format_ip4_address, &tc->c_lcl_ip4,
654 clib_net_to_host_u16 (tc->c_lcl_port), format_ip4_address,
655 &tc->c_rmt_ip4, clib_net_to_host_u16 (tc->c_rmt_port));
659 s = format (s, "[#%d][%s] %U:%d->%U:%d", tc->c_thread_index, "T",
660 format_ip6_address, &tc->c_lcl_ip6,
661 clib_net_to_host_u16 (tc->c_lcl_port), format_ip6_address,
662 &tc->c_rmt_ip6, clib_net_to_host_u16 (tc->c_rmt_port));
669 format_tcp_connection (u8 * s, va_list * args)
671 tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
672 u32 verbose = va_arg (*args, u32);
674 s = format (s, "%-50U", format_tcp_connection_id, tc);
677 s = format (s, "%-15U", format_tcp_state, tc->state);
679 s = format (s, " %U\n%U", format_tcp_timers, tc, format_tcp_vars, tc);
685 format_tcp_session (u8 * s, va_list * args)
687 u32 tci = va_arg (*args, u32);
688 u32 thread_index = va_arg (*args, u32);
689 u32 verbose = va_arg (*args, u32);
690 tcp_connection_t *tc;
692 tc = tcp_connection_get (tci, thread_index);
694 s = format (s, "%U", format_tcp_connection, tc, verbose);
696 s = format (s, "empty");
701 format_tcp_listener_session (u8 * s, va_list * args)
703 u32 tci = va_arg (*args, u32);
704 tcp_connection_t *tc = tcp_listener_get (tci);
705 return format (s, "%U", format_tcp_connection_id, tc);
709 format_tcp_half_open_session (u8 * s, va_list * args)
711 u32 tci = va_arg (*args, u32);
712 tcp_connection_t *tc = tcp_half_open_connection_get (tci);
713 return format (s, "%U", format_tcp_connection_id, tc);
717 format_tcp_sacks (u8 * s, va_list * args)
719 tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
720 sack_block_t *sacks = tc->snd_sacks;
722 vec_foreach (block, sacks)
724 s = format (s, " start %u end %u\n", block->start - tc->irs,
725 block->end - tc->irs);
731 format_tcp_sack_hole (u8 * s, va_list * args)
733 sack_scoreboard_hole_t *hole = va_arg (*args, sack_scoreboard_hole_t *);
734 s = format (s, "[%u, %u]", hole->start, hole->end);
739 format_tcp_scoreboard (u8 * s, va_list * args)
741 sack_scoreboard_t *sb = va_arg (*args, sack_scoreboard_t *);
742 sack_scoreboard_hole_t *hole;
743 s = format (s, "sacked_bytes %u last_sacked_bytes %u lost_bytes %u\n",
744 sb->sacked_bytes, sb->last_sacked_bytes, sb->lost_bytes);
745 s = format (s, " last_bytes_delivered %u high_sacked %u snd_una_adv %u\n",
746 sb->last_bytes_delivered, sb->high_sacked, sb->snd_una_adv);
747 s = format (s, " cur_rxt_hole %u high_rxt %u rescue_rxt %u",
748 sb->cur_rxt_hole, sb->high_rxt, sb->rescue_rxt);
750 hole = scoreboard_first_hole (sb);
752 s = format (s, "\n head %u tail %u holes:\n", sb->head, sb->tail);
756 s = format (s, "%U", format_tcp_sack_hole, hole);
757 hole = scoreboard_next_hole (sb, hole);
762 transport_connection_t *
763 tcp_session_get_transport (u32 conn_index, u32 thread_index)
765 tcp_connection_t *tc = tcp_connection_get (conn_index, thread_index);
766 return &tc->connection;
769 transport_connection_t *
770 tcp_half_open_session_get_transport (u32 conn_index)
772 tcp_connection_t *tc = tcp_half_open_connection_get (conn_index);
773 return &tc->connection;
777 * Compute maximum segment size for session layer.
779 * Since the result needs to be the actual data length, it first computes
780 * the tcp options to be used in the next burst and subtracts their
781 * length from the connection's snd_mss.
784 tcp_session_send_mss (transport_connection_t * trans_conn)
786 tcp_connection_t *tc = (tcp_connection_t *) trans_conn;
788 /* Ensure snd_mss does accurately reflect the amount of data we can push
789 * in a segment. This also makes sure that options are updated according to
790 * the current state of the connection. */
791 tcp_update_snd_mss (tc);
797 tcp_round_snd_space (tcp_connection_t * tc, u32 snd_space)
799 if (tc->snd_wnd < tc->snd_mss)
801 return tc->snd_wnd <= snd_space ? tc->snd_wnd : 0;
804 /* If we can't write at least a segment, don't try at all */
805 if (snd_space < tc->snd_mss)
808 /* round down to mss multiple */
809 return snd_space - (snd_space % tc->snd_mss);
813 * Compute tx window session is allowed to fill.
815 * Takes into account available send space, snd_mss and the congestion
816 * state of the connection. If possible, the value returned is a multiple
819 * @param tc tcp connection
820 * @return number of bytes session is allowed to write
823 tcp_snd_space (tcp_connection_t * tc)
825 int snd_space, snt_limited;
827 if (PREDICT_TRUE (tcp_in_cong_recovery (tc) == 0))
829 snd_space = tcp_available_snd_space (tc);
831 /* If we haven't gotten dupacks or if we did and have gotten sacked
832 * bytes then we can still send as per Limited Transmit (RFC3042) */
833 if (PREDICT_FALSE (tc->rcv_dupacks != 0
834 && (tcp_opts_sack_permitted (tc)
835 && tc->sack_sb.last_sacked_bytes == 0)))
837 if (tc->rcv_dupacks == 1 && tc->limited_transmit != tc->snd_nxt)
838 tc->limited_transmit = tc->snd_nxt;
839 ASSERT (seq_leq (tc->limited_transmit, tc->snd_nxt));
841 snt_limited = tc->snd_nxt - tc->limited_transmit;
842 snd_space = clib_max (2 * tc->snd_mss - snt_limited, 0);
844 return tcp_round_snd_space (tc, snd_space);
847 if (tcp_in_recovery (tc))
849 tc->snd_nxt = tc->snd_una_max;
850 snd_space = tcp_available_wnd (tc) - tc->snd_rxt_bytes
851 - (tc->snd_una_max - tc->snd_congestion);
852 if (snd_space <= 0 || (tc->snd_una_max - tc->snd_una) >= tc->snd_wnd)
854 return tcp_round_snd_space (tc, snd_space);
857 /* If in fast recovery, send 1 SMSS if wnd allows */
858 if (tcp_in_fastrecovery (tc)
859 && tcp_available_snd_space (tc) && !tcp_fastrecovery_sent_1_smss (tc))
861 tcp_fastrecovery_1_smss_on (tc);
869 tcp_session_send_space (transport_connection_t * trans_conn)
871 tcp_connection_t *tc = (tcp_connection_t *) trans_conn;
872 return tcp_snd_space (tc);
876 tcp_rcv_wnd_available (tcp_connection_t * tc)
878 return (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
882 tcp_session_tx_fifo_offset (transport_connection_t * trans_conn)
884 tcp_connection_t *tc = (tcp_connection_t *) trans_conn;
886 ASSERT (seq_geq (tc->snd_nxt, tc->snd_una));
888 /* This still works if fast retransmit is on */
889 return (tc->snd_nxt - tc->snd_una);
893 const static transport_proto_vft_t tcp4_proto = {
894 .bind = tcp_session_bind_ip4,
895 .unbind = tcp_session_unbind,
896 .push_header = tcp_push_header,
897 .get_connection = tcp_session_get_transport,
898 .get_listener = tcp_session_get_listener,
899 .get_half_open = tcp_half_open_session_get_transport,
900 .open = tcp_session_open_ip4,
901 .close = tcp_session_close,
902 .cleanup = tcp_session_cleanup,
903 .send_mss = tcp_session_send_mss,
904 .send_space = tcp_session_send_space,
905 .tx_fifo_offset = tcp_session_tx_fifo_offset,
906 .format_connection = format_tcp_session,
907 .format_listener = format_tcp_listener_session,
908 .format_half_open = format_tcp_half_open_session,
911 const static transport_proto_vft_t tcp6_proto = {
912 .bind = tcp_session_bind_ip6,
913 .unbind = tcp_session_unbind,
914 .push_header = tcp_push_header,
915 .get_connection = tcp_session_get_transport,
916 .get_listener = tcp_session_get_listener,
917 .get_half_open = tcp_half_open_session_get_transport,
918 .open = tcp_session_open_ip6,
919 .close = tcp_session_close,
920 .cleanup = tcp_session_cleanup,
921 .send_mss = tcp_session_send_mss,
922 .send_space = tcp_session_send_space,
923 .tx_fifo_offset = tcp_session_tx_fifo_offset,
924 .format_connection = format_tcp_session,
925 .format_listener = format_tcp_listener_session,
926 .format_half_open = format_tcp_half_open_session,
931 tcp_timer_keep_handler (u32 conn_index)
933 u32 thread_index = vlib_get_thread_index ();
934 tcp_connection_t *tc;
936 tc = tcp_connection_get (conn_index, thread_index);
937 tc->timers[TCP_TIMER_KEEP] = TCP_TIMER_HANDLE_INVALID;
939 tcp_connection_close (tc);
943 tcp_timer_establish_handler (u32 conn_index)
945 tcp_connection_t *tc;
948 tc = tcp_half_open_connection_get (conn_index);
949 tc->timers[TCP_TIMER_ESTABLISH] = TCP_TIMER_HANDLE_INVALID;
951 ASSERT (tc->state == TCP_STATE_SYN_SENT);
953 sst = tc->c_is_ip4 ? SESSION_TYPE_IP4_TCP : SESSION_TYPE_IP6_TCP;
954 stream_session_connect_notify (&tc->connection, sst, 1 /* fail */ );
956 tcp_connection_cleanup (tc);
960 tcp_timer_waitclose_handler (u32 conn_index)
962 u32 thread_index = vlib_get_thread_index ();
963 tcp_connection_t *tc;
965 tc = tcp_connection_get (conn_index, thread_index);
966 tc->timers[TCP_TIMER_WAITCLOSE] = TCP_TIMER_HANDLE_INVALID;
968 /* Session didn't come back with a close(). Send FIN either way
969 * and switch to LAST_ACK. */
970 if (tc->state == TCP_STATE_CLOSE_WAIT)
972 if (tc->flags & TCP_CONN_FINSNT)
974 clib_warning ("FIN was sent and still in CLOSE WAIT. Weird!");
978 tc->state = TCP_STATE_LAST_ACK;
980 /* Make sure we don't wait in LAST ACK forever */
981 tcp_timer_set (tc, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
983 /* Don't delete the connection yet */
987 tcp_connection_del (tc);
991 static timer_expiration_handler *timer_expiration_handlers[TCP_N_TIMERS] =
993 tcp_timer_retransmit_handler,
994 tcp_timer_delack_handler,
995 tcp_timer_persist_handler,
996 tcp_timer_keep_handler,
997 tcp_timer_waitclose_handler,
998 tcp_timer_retransmit_syn_handler,
999 tcp_timer_establish_handler
1004 tcp_expired_timers_dispatch (u32 * expired_timers)
1007 u32 connection_index, timer_id;
1009 for (i = 0; i < vec_len (expired_timers); i++)
1011 /* Get session index and timer id */
1012 connection_index = expired_timers[i] & 0x0FFFFFFF;
1013 timer_id = expired_timers[i] >> 28;
1015 TCP_EVT_DBG (TCP_EVT_TIMER_POP, connection_index, timer_id);
1017 /* Handle expiration */
1018 (*timer_expiration_handlers[timer_id]) (connection_index);
1023 tcp_initialize_timer_wheels (tcp_main_t * tm)
1025 tw_timer_wheel_16t_2w_512sl_t *tw;
1027 foreach_vlib_main (({
1028 tw = &tm->timer_wheels[ii];
1029 tw_timer_wheel_init_16t_2w_512sl (tw, tcp_expired_timers_dispatch,
1030 100e-3 /* timer period 100ms */ , ~0);
1031 tw->last_run_time = vlib_time_now (this_vlib_main);
1037 tcp_main_enable (vlib_main_t * vm)
1039 tcp_main_t *tm = vnet_get_tcp_main ();
1040 ip_protocol_info_t *pi;
1041 ip_main_t *im = &ip_main;
1042 vlib_thread_main_t *vtm = vlib_get_thread_main ();
1043 clib_error_t *error = 0;
1046 if ((error = vlib_call_init_function (vm, ip_main_init)))
1048 if ((error = vlib_call_init_function (vm, ip4_lookup_init)))
1050 if ((error = vlib_call_init_function (vm, ip6_lookup_init)))
1057 /* Register with IP */
1058 pi = ip_get_protocol_info (im, IP_PROTOCOL_TCP);
1060 return clib_error_return (0, "TCP protocol info AWOL");
1061 pi->format_header = format_tcp_header;
1062 pi->unformat_pg_edit = unformat_pg_tcp_header;
1064 ip4_register_protocol (IP_PROTOCOL_TCP, tcp4_input_node.index);
1066 /* Register as transport with URI */
1067 session_register_transport (SESSION_TYPE_IP4_TCP, &tcp4_proto);
1068 session_register_transport (SESSION_TYPE_IP6_TCP, &tcp6_proto);
1071 * Initialize data structures
1074 num_threads = 1 /* main thread */ + vtm->n_threads;
1075 vec_validate (tm->connections, num_threads - 1);
1077 /* Initialize per worker thread tx buffers (used for control messages) */
1078 vec_validate (tm->tx_buffers, num_threads - 1);
1080 /* Initialize timer wheels */
1081 vec_validate (tm->timer_wheels, num_threads - 1);
1082 tcp_initialize_timer_wheels (tm);
1084 /* Initialize clocks per tick for TCP timestamp. Used to compute
1085 * monotonically increasing timestamps. */
1086 tm->tstamp_ticks_per_clock = vm->clib_time.seconds_per_clock
1087 / TCP_TSTAMP_RESOLUTION;
1089 clib_bihash_init_24_8 (&tm->local_endpoints_table, "local endpoint table",
1090 200000 /* $$$$ config parameter nbuckets */ ,
1091 (64 << 20) /*$$$ config parameter table size */ );
1097 vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en)
1101 if (tcp_main.is_enabled)
1104 return tcp_main_enable (vm);
1108 tcp_main.is_enabled = 0;
1115 tcp_init (vlib_main_t * vm)
1117 tcp_main_t *tm = vnet_get_tcp_main ();
1120 tm->vnet_main = vnet_get_main ();
1126 VLIB_INIT_FUNCTION (tcp_init);
1129 * fd.io coding-style-patch-verification: ON
1132 * eval: (c-set-style "gnu")