2 * Copyright (c) 2016-2019 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 <vppinfra/sparse_vec.h>
17 #include <vnet/fib/ip4_fib.h>
18 #include <vnet/fib/ip6_fib.h>
19 #include <vnet/tcp/tcp_packet.h>
20 #include <vnet/tcp/tcp.h>
21 #include <vnet/session/session.h>
24 static char *tcp_error_strings[] = {
25 #define tcp_error(n,s) s,
26 #include <vnet/tcp/tcp_error.def>
30 /* All TCP nodes have the same outgoing arcs */
31 #define foreach_tcp_state_next \
32 _ (DROP4, "ip4-drop") \
33 _ (DROP6, "ip6-drop") \
34 _ (TCP4_OUTPUT, "tcp4-output") \
35 _ (TCP6_OUTPUT, "tcp6-output")
37 typedef enum _tcp_established_next
39 #define _(s,n) TCP_ESTABLISHED_NEXT_##s,
40 foreach_tcp_state_next
42 TCP_ESTABLISHED_N_NEXT,
43 } tcp_established_next_t;
45 typedef enum _tcp_rcv_process_next
47 #define _(s,n) TCP_RCV_PROCESS_NEXT_##s,
48 foreach_tcp_state_next
50 TCP_RCV_PROCESS_N_NEXT,
51 } tcp_rcv_process_next_t;
53 typedef enum _tcp_syn_sent_next
55 #define _(s,n) TCP_SYN_SENT_NEXT_##s,
56 foreach_tcp_state_next
59 } tcp_syn_sent_next_t;
61 typedef enum _tcp_listen_next
63 #define _(s,n) TCP_LISTEN_NEXT_##s,
64 foreach_tcp_state_next
69 /* Generic, state independent indices */
70 typedef enum _tcp_state_next
72 #define _(s,n) TCP_NEXT_##s,
73 foreach_tcp_state_next
78 #define tcp_next_output(is_ip4) (is_ip4 ? TCP_NEXT_TCP4_OUTPUT \
79 : TCP_NEXT_TCP6_OUTPUT)
81 #define tcp_next_drop(is_ip4) (is_ip4 ? TCP_NEXT_DROP4 \
85 * Validate segment sequence number. As per RFC793:
87 * Segment Receive Test
89 * ------- ------- -------------------------------------------
90 * 0 0 SEG.SEQ = RCV.NXT
91 * 0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
93 * >0 >0 RCV.NXT =< SEG.SEQ < RCV.NXT+RCV.WND
94 * or RCV.NXT =< SEG.SEQ+SEG.LEN-1 < RCV.NXT+RCV.WND
96 * This ultimately consists in checking if segment falls within the window.
97 * The one important difference compared to RFC793 is that we use rcv_las,
98 * or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
99 * peer's reference when computing our receive window.
102 * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
103 * however, is too strict when we have retransmits. Instead we just check that
104 * the seq is not beyond the right edge and that the end of the segment is not
105 * less than the left edge.
107 * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
108 * use rcv_nxt in the right edge window test instead of rcv_las.
112 tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
114 return (seq_geq (end_seq, tc->rcv_las)
115 && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
119 * Parse TCP header options.
121 * @param th TCP header
122 * @param to TCP options data structure to be populated
123 * @param is_syn set if packet is syn
124 * @return -1 if parsing failed
127 tcp_options_parse (tcp_header_t * th, tcp_options_t * to, u8 is_syn)
130 u8 opt_len, opts_len, kind;
134 opts_len = (tcp_doff (th) << 2) - sizeof (tcp_header_t);
135 data = (const u8 *) (th + 1);
137 /* Zero out all flags but those set in SYN */
138 to->flags &= (TCP_OPTS_FLAG_SACK_PERMITTED | TCP_OPTS_FLAG_WSCALE
139 | TCP_OPTS_FLAG_TSTAMP | TCP_OPTS_FLAG_MSS);
141 for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
145 /* Get options length */
146 if (kind == TCP_OPTION_EOL)
148 else if (kind == TCP_OPTION_NOOP)
160 /* weird option length */
161 if (opt_len < 2 || opt_len > opts_len)
171 if ((opt_len == TCP_OPTION_LEN_MSS) && tcp_syn (th))
173 to->flags |= TCP_OPTS_FLAG_MSS;
174 to->mss = clib_net_to_host_u16 (*(u16 *) (data + 2));
177 case TCP_OPTION_WINDOW_SCALE:
180 if ((opt_len == TCP_OPTION_LEN_WINDOW_SCALE) && tcp_syn (th))
182 to->flags |= TCP_OPTS_FLAG_WSCALE;
183 to->wscale = data[2];
184 if (to->wscale > TCP_MAX_WND_SCALE)
185 to->wscale = TCP_MAX_WND_SCALE;
188 case TCP_OPTION_TIMESTAMP:
190 to->flags |= TCP_OPTS_FLAG_TSTAMP;
191 if ((to->flags & TCP_OPTS_FLAG_TSTAMP)
192 && opt_len == TCP_OPTION_LEN_TIMESTAMP)
194 to->tsval = clib_net_to_host_u32 (*(u32 *) (data + 2));
195 to->tsecr = clib_net_to_host_u32 (*(u32 *) (data + 6));
198 case TCP_OPTION_SACK_PERMITTED:
201 if (opt_len == TCP_OPTION_LEN_SACK_PERMITTED && tcp_syn (th))
202 to->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
204 case TCP_OPTION_SACK_BLOCK:
205 /* If SACK permitted was not advertised or a SYN, break */
206 if ((to->flags & TCP_OPTS_FLAG_SACK_PERMITTED) == 0 || tcp_syn (th))
209 /* If too short or not correctly formatted, break */
210 if (opt_len < 10 || ((opt_len - 2) % TCP_OPTION_LEN_SACK_BLOCK))
213 to->flags |= TCP_OPTS_FLAG_SACK;
214 to->n_sack_blocks = (opt_len - 2) / TCP_OPTION_LEN_SACK_BLOCK;
215 vec_reset_length (to->sacks);
216 for (j = 0; j < to->n_sack_blocks; j++)
218 b.start = clib_net_to_host_u32 (*(u32 *) (data + 2 + 8 * j));
219 b.end = clib_net_to_host_u32 (*(u32 *) (data + 6 + 8 * j));
220 vec_add1 (to->sacks, b);
224 /* Nothing to see here */
232 * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
233 * timestamp to echo and it's less than tsval_recent, drop segment
234 * but still send an ACK in order to retain TCP's mechanism for detecting
235 * and recovering from half-open connections
237 * Or at least that's what the theory says. It seems that this might not work
238 * very well with packet reordering and fast retransmit. XXX
241 tcp_segment_check_paws (tcp_connection_t * tc)
243 return tcp_opts_tstamp (&tc->rcv_opts)
244 && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
248 * Update tsval recent
251 tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
254 * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
255 * of an incoming segment:
256 * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
257 * then the TSval from the segment is copied to TS.Recent;
258 * otherwise, the TSval is ignored.
260 if (tcp_opts_tstamp (&tc->rcv_opts) && seq_leq (seq, tc->rcv_las)
261 && seq_leq (tc->rcv_las, seq_end))
263 ASSERT (timestamp_leq (tc->tsval_recent, tc->rcv_opts.tsval));
264 tc->tsval_recent = tc->rcv_opts.tsval;
265 tc->tsval_recent_age = tcp_time_now_w_thread (tc->c_thread_index);
270 tcp_handle_rst (tcp_connection_t * tc)
272 switch (tc->rst_state)
274 case TCP_STATE_SYN_RCVD:
275 /* Cleanup everything. App wasn't notified yet */
276 session_transport_delete_notify (&tc->connection);
277 tcp_connection_cleanup (tc);
279 case TCP_STATE_SYN_SENT:
280 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
281 tcp_connection_cleanup (tc);
283 case TCP_STATE_ESTABLISHED:
284 session_transport_reset_notify (&tc->connection);
285 session_transport_closed_notify (&tc->connection);
287 case TCP_STATE_CLOSE_WAIT:
288 case TCP_STATE_FIN_WAIT_1:
289 case TCP_STATE_FIN_WAIT_2:
290 case TCP_STATE_CLOSING:
291 case TCP_STATE_LAST_ACK:
292 session_transport_closed_notify (&tc->connection);
294 case TCP_STATE_CLOSED:
295 case TCP_STATE_TIME_WAIT:
298 TCP_DBG ("reset state: %u", tc->state);
303 tcp_program_reset_ntf (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
305 if (!tcp_disconnect_pending (tc))
307 tc->rst_state = tc->state;
308 vec_add1 (wrk->pending_resets, tc->c_c_index);
309 tcp_disconnect_pending_on (tc);
314 * Handle reset packet
316 * Programs disconnect/reset notification that should be sent
317 * later by calling @ref tcp_handle_disconnects
320 tcp_rcv_rst (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
322 TCP_EVT (TCP_EVT_RST_RCVD, tc);
325 case TCP_STATE_SYN_RCVD:
326 tcp_program_reset_ntf (wrk, tc);
327 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
329 case TCP_STATE_SYN_SENT:
330 /* Do not program ntf because the connection is half-open */
333 case TCP_STATE_ESTABLISHED:
334 tcp_connection_timers_reset (tc);
335 tcp_cong_recovery_off (tc);
336 tcp_program_reset_ntf (wrk, tc);
337 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
338 tcp_program_cleanup (wrk, tc);
340 case TCP_STATE_CLOSE_WAIT:
341 case TCP_STATE_FIN_WAIT_1:
342 case TCP_STATE_FIN_WAIT_2:
343 case TCP_STATE_CLOSING:
344 case TCP_STATE_LAST_ACK:
345 tcp_connection_timers_reset (tc);
346 tcp_cong_recovery_off (tc);
347 tcp_program_reset_ntf (wrk, tc);
348 /* Make sure we mark the session as closed. In some states we may
349 * be still trying to send data */
350 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
351 tcp_program_cleanup (wrk, tc);
353 case TCP_STATE_CLOSED:
354 case TCP_STATE_TIME_WAIT:
357 TCP_DBG ("reset state: %u", tc->state);
362 * Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
364 * It first verifies if segment has a wrapped sequence number (PAWS) and then
365 * does the processing associated to the first four steps (ignoring security
366 * and precedence): sequence number, rst bit and syn bit checks.
368 * @return 0 if segments passes validation.
371 tcp_segment_validate (tcp_worker_ctx_t * wrk, tcp_connection_t * tc0,
372 vlib_buffer_t * b0, tcp_header_t * th0, u32 * error0)
374 /* We could get a burst of RSTs interleaved with acks */
375 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
377 tcp_send_reset (tc0);
378 *error0 = TCP_ERROR_CONNECTION_CLOSED;
382 if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
384 *error0 = TCP_ERROR_SEGMENT_INVALID;
388 if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts, 0)))
390 *error0 = TCP_ERROR_OPTIONS;
394 if (PREDICT_FALSE (tcp_segment_check_paws (tc0)))
396 *error0 = TCP_ERROR_PAWS;
397 TCP_EVT (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
398 vnet_buffer (b0)->tcp.seq_end);
400 /* If it just so happens that a segment updates tsval_recent for a
401 * segment over 24 days old, invalidate tsval_recent. */
402 if (timestamp_lt (tc0->tsval_recent_age + TCP_PAWS_IDLE,
403 tcp_time_now_w_thread (tc0->c_thread_index)))
405 tc0->tsval_recent = tc0->rcv_opts.tsval;
406 clib_warning ("paws failed: 24-day old segment");
408 /* Drop after ack if not rst. Resets can fail paws check as per
409 * RFC 7323 sec. 5.2: When an <RST> segment is received, it MUST NOT
410 * be subjected to the PAWS check by verifying an acceptable value in
412 else if (!tcp_rst (th0))
414 tcp_program_ack (tc0);
415 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
420 /* 1st: check sequence number */
421 if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
422 vnet_buffer (b0)->tcp.seq_end))
424 /* SYN/SYN-ACK retransmit */
426 && vnet_buffer (b0)->tcp.seq_number == tc0->rcv_nxt - 1)
428 tcp_options_parse (th0, &tc0->rcv_opts, 1);
429 if (tc0->state == TCP_STATE_SYN_RCVD)
431 tcp_send_synack (tc0);
432 TCP_EVT (TCP_EVT_SYN_RCVD, tc0, 0);
433 *error0 = TCP_ERROR_SYNS_RCVD;
437 tcp_program_ack (tc0);
438 TCP_EVT (TCP_EVT_SYNACK_RCVD, tc0);
439 *error0 = TCP_ERROR_SYN_ACKS_RCVD;
444 /* If our window is 0 and the packet is in sequence, let it pass
445 * through for ack processing. It should be dropped later. */
446 if (tc0->rcv_wnd < tc0->snd_mss
447 && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
450 /* If we entered recovery and peer did so as well, there's a chance that
451 * dup acks won't be acceptable on either end because seq_end may be less
452 * than rcv_las. This can happen if acks are lost in both directions. */
453 if (tcp_in_recovery (tc0)
454 && seq_geq (vnet_buffer (b0)->tcp.seq_number,
455 tc0->rcv_las - tc0->rcv_wnd)
456 && seq_leq (vnet_buffer (b0)->tcp.seq_end,
457 tc0->rcv_nxt + tc0->rcv_wnd))
460 *error0 = TCP_ERROR_RCV_WND;
462 /* If we advertised a zero rcv_wnd and the segment is in the past or the
463 * next one that we expect, it is probably a window probe */
464 if ((tc0->flags & TCP_CONN_ZERO_RWND_SENT)
465 && seq_lt (vnet_buffer (b0)->tcp.seq_end,
466 tc0->rcv_las + tc0->rcv_opts.mss))
467 *error0 = TCP_ERROR_ZERO_RWND;
469 tc0->errors.below_data_wnd += seq_lt (vnet_buffer (b0)->tcp.seq_end,
472 /* If not RST, send dup ack */
475 tcp_program_dupack (tc0);
476 TCP_EVT (TCP_EVT_DUPACK_SENT, tc0, vnet_buffer (b0)->tcp);
484 /* 2nd: check the RST bit */
485 if (PREDICT_FALSE (tcp_rst (th0)))
487 tcp_rcv_rst (wrk, tc0);
488 *error0 = TCP_ERROR_RST_RCVD;
492 /* 3rd: check security and precedence (skip) */
494 /* 4th: check the SYN bit (in window) */
495 if (PREDICT_FALSE (tcp_syn (th0)))
497 /* As per RFC5961 send challenge ack instead of reset */
498 tcp_program_ack (tc0);
499 *error0 = TCP_ERROR_SPURIOUS_SYN;
503 /* If segment in window, save timestamp */
504 tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
505 vnet_buffer (b0)->tcp.seq_end);
513 tcp_rcv_ack_no_cc (tcp_connection_t * tc, vlib_buffer_t * b, u32 * error)
515 /* SND.UNA =< SEG.ACK =< SND.NXT */
516 if (!(seq_leq (tc->snd_una, vnet_buffer (b)->tcp.ack_number)
517 && seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
519 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
520 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
522 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
525 *error = TCP_ERROR_ACK_INVALID;
530 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
531 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
532 *error = TCP_ERROR_ACK_OK;
537 * Compute smoothed RTT as per VJ's '88 SIGCOMM and RFC6298
539 * Note that although the original article, srtt and rttvar are scaled
540 * to minimize round-off errors, here we don't. Instead, we rely on
541 * better precision time measurements.
543 * TODO support us rtt resolution
546 tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
552 err = mrtt - tc->srtt;
554 /* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
555 * The increase should be bound */
556 tc->srtt = clib_max ((int) tc->srtt + (err >> 3), 1);
557 diff = (clib_abs (err) - (int) tc->rttvar) >> 2;
558 tc->rttvar = clib_max ((int) tc->rttvar + diff, 1);
562 /* First measurement. */
564 tc->rttvar = mrtt >> 1;
568 #ifndef CLIB_MARCH_VARIANT
570 tcp_update_rto (tcp_connection_t * tc)
572 tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
573 tc->rto = clib_max (tc->rto, TCP_RTO_MIN);
575 #endif /* CLIB_MARCH_VARIANT */
578 * Update RTT estimate and RTO timer
580 * Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
581 * timing. Middle boxes are known to fiddle with TCP options so we
582 * should give higher priority to ACK timing.
584 * This should be called only if previously sent bytes have been acked.
586 * return 1 if valid rtt 0 otherwise
589 tcp_update_rtt (tcp_connection_t * tc, tcp_rate_sample_t * rs, u32 ack)
593 /* Karn's rule, part 1. Don't use retransmitted segments to estimate
594 * RTT because they're ambiguous. */
595 if (tcp_in_cong_recovery (tc))
597 /* Accept rtt estimates for samples that have not been retransmitted */
598 if ((tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
599 && !(rs->flags & TCP_BTS_IS_RXT))
601 mrtt = rs->rtt_time * THZ;
607 if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq))
609 f64 sample = tcp_time_now_us (tc->c_thread_index) - tc->rtt_ts;
610 tc->mrtt_us = tc->mrtt_us + (sample - tc->mrtt_us) * 0.125;
611 mrtt = clib_max ((u32) (sample * THZ), 1);
612 /* Allow measuring of a new RTT */
615 /* As per RFC7323 TSecr can be used for RTTM only if the segment advances
616 * snd_una, i.e., the left side of the send window:
617 * seq_lt (tc->snd_una, ack). This is a condition for calling update_rtt */
618 else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr)
620 u32 now = tcp_tstamp (tc);
621 mrtt = clib_max (now - tc->rcv_opts.tsecr, 1);
626 /* Ignore dubious measurements */
627 if (mrtt == 0 || mrtt > TCP_RTT_MAX)
630 tcp_estimate_rtt (tc, mrtt);
634 /* If we got here something must've been ACKed so make sure boff is 0,
635 * even if mrtt is not valid since we update the rto lower */
643 tcp_estimate_initial_rtt (tcp_connection_t * tc)
645 u8 thread_index = vlib_num_workers ()? 1 : 0;
650 tc->mrtt_us = tcp_time_now_us (thread_index) - tc->rtt_ts;
651 tc->mrtt_us = clib_max (tc->mrtt_us, 0.0001);
652 mrtt = clib_max ((u32) (tc->mrtt_us * THZ), 1);
657 mrtt = tcp_time_now_w_thread (thread_index) - tc->rcv_opts.tsecr;
658 mrtt = clib_max (mrtt, 1);
659 /* Due to retransmits we don't know the initial mrtt */
660 if (tc->rto_boff && mrtt > 1 * THZ)
662 tc->mrtt_us = (f64) mrtt *TCP_TICK;
665 if (mrtt > 0 && mrtt < TCP_RTT_MAX)
666 tcp_estimate_rtt (tc, mrtt);
671 * Dequeue bytes for connections that have received acks in last burst
674 tcp_handle_postponed_dequeues (tcp_worker_ctx_t * wrk)
676 u32 thread_index = wrk->vm->thread_index;
677 u32 *pending_deq_acked;
678 tcp_connection_t *tc;
681 if (!vec_len (wrk->pending_deq_acked))
684 pending_deq_acked = wrk->pending_deq_acked;
685 for (i = 0; i < vec_len (pending_deq_acked); i++)
687 tc = tcp_connection_get (pending_deq_acked[i], thread_index);
688 tc->flags &= ~TCP_CONN_DEQ_PENDING;
690 if (PREDICT_FALSE (!tc->burst_acked))
693 /* Dequeue the newly ACKed bytes */
694 session_tx_fifo_dequeue_drop (&tc->connection, tc->burst_acked);
695 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
697 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
699 if (seq_leq (tc->psh_seq, tc->snd_una))
700 tc->flags &= ~TCP_CONN_PSH_PENDING;
703 /* If everything has been acked, stop retransmit timer
704 * otherwise update. */
705 tcp_retransmit_timer_update (tc);
707 /* Update pacer based on our new cwnd estimate */
708 tcp_connection_tx_pacer_update (tc);
712 _vec_len (wrk->pending_deq_acked) = 0;
716 tcp_program_dequeue (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
718 if (!(tc->flags & TCP_CONN_DEQ_PENDING))
720 vec_add1 (wrk->pending_deq_acked, tc->c_c_index);
721 tc->flags |= TCP_CONN_DEQ_PENDING;
723 tc->burst_acked += tc->bytes_acked;
726 #ifndef CLIB_MARCH_VARIANT
728 scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
730 ASSERT (!pool_is_free_index (sb->holes, hole - sb->holes));
731 return hole - sb->holes;
735 scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
737 return hole->end - hole->start;
740 sack_scoreboard_hole_t *
741 scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
743 if (index != TCP_INVALID_SACK_HOLE_INDEX)
744 return pool_elt_at_index (sb->holes, index);
748 sack_scoreboard_hole_t *
749 scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
751 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
752 return pool_elt_at_index (sb->holes, hole->next);
756 sack_scoreboard_hole_t *
757 scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
759 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
760 return pool_elt_at_index (sb->holes, hole->prev);
764 sack_scoreboard_hole_t *
765 scoreboard_first_hole (sack_scoreboard_t * sb)
767 if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
768 return pool_elt_at_index (sb->holes, sb->head);
772 sack_scoreboard_hole_t *
773 scoreboard_last_hole (sack_scoreboard_t * sb)
775 if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
776 return pool_elt_at_index (sb->holes, sb->tail);
781 scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
783 sack_scoreboard_hole_t *next, *prev;
785 if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
787 next = pool_elt_at_index (sb->holes, hole->next);
788 next->prev = hole->prev;
792 sb->tail = hole->prev;
795 if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
797 prev = pool_elt_at_index (sb->holes, hole->prev);
798 prev->next = hole->next;
802 sb->head = hole->next;
805 if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
806 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
808 /* Poison the entry */
810 clib_memset (hole, 0xfe, sizeof (*hole));
812 pool_put (sb->holes, hole);
815 static sack_scoreboard_hole_t *
816 scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
819 sack_scoreboard_hole_t *hole, *next, *prev;
822 pool_get (sb->holes, hole);
823 clib_memset (hole, 0, sizeof (*hole));
827 hole_index = scoreboard_hole_index (sb, hole);
829 prev = scoreboard_get_hole (sb, prev_index);
832 hole->prev = prev_index;
833 hole->next = prev->next;
835 if ((next = scoreboard_next_hole (sb, hole)))
836 next->prev = hole_index;
838 sb->tail = hole_index;
840 prev->next = hole_index;
844 sb->head = hole_index;
845 hole->prev = TCP_INVALID_SACK_HOLE_INDEX;
846 hole->next = TCP_INVALID_SACK_HOLE_INDEX;
853 scoreboard_update_sacked_rxt (sack_scoreboard_t * sb, u32 start, u32 end,
856 if (!has_rxt || seq_geq (start, sb->high_rxt))
860 seq_lt (end, sb->high_rxt) ? (end - start) : (sb->high_rxt - start);
864 scoreboard_update_bytes (sack_scoreboard_t * sb, u32 ack, u32 snd_mss)
866 sack_scoreboard_hole_t *left, *right;
867 u32 sacked = 0, blks = 0, old_sacked;
869 old_sacked = sb->sacked_bytes;
871 sb->last_lost_bytes = 0;
873 sb->sacked_bytes = 0;
875 right = scoreboard_last_hole (sb);
878 sb->sacked_bytes = sb->high_sacked - ack;
879 sb->last_sacked_bytes = sb->sacked_bytes
880 - (old_sacked - sb->last_bytes_delivered);
884 if (seq_gt (sb->high_sacked, right->end))
886 sacked = sb->high_sacked - right->end;
890 while (sacked < (TCP_DUPACK_THRESHOLD - 1) * snd_mss
891 && blks < TCP_DUPACK_THRESHOLD)
894 sb->lost_bytes += scoreboard_hole_bytes (right);
896 left = scoreboard_prev_hole (sb, right);
899 ASSERT (right->start == ack || sb->is_reneging);
900 sacked += right->start - ack;
905 sacked += right->start - left->end;
910 /* right is first lost */
913 sb->lost_bytes += scoreboard_hole_bytes (right);
914 sb->last_lost_bytes += right->is_lost ? 0 : (right->end - right->start);
916 left = scoreboard_prev_hole (sb, right);
919 ASSERT (right->start == ack || sb->is_reneging);
920 sacked += right->start - ack;
923 sacked += right->start - left->end;
927 sb->sacked_bytes = sacked;
928 sb->last_sacked_bytes = sacked - (old_sacked - sb->last_bytes_delivered);
932 * Figure out the next hole to retransmit
934 * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
936 sack_scoreboard_hole_t *
937 scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
938 sack_scoreboard_hole_t * start,
939 u8 have_unsent, u8 * can_rescue, u8 * snd_limited)
941 sack_scoreboard_hole_t *hole = 0;
943 hole = start ? start : scoreboard_first_hole (sb);
944 while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
945 hole = scoreboard_next_hole (sb, hole);
947 /* Nothing, return */
950 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
954 /* Rule (1): if higher than rxt, less than high_sacked and lost */
955 if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
957 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
961 /* Rule (2): available unsent data */
964 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
967 /* Rule (3): if hole not lost */
968 else if (seq_lt (hole->start, sb->high_sacked))
970 /* And we didn't already retransmit it */
971 if (seq_leq (hole->end, sb->high_rxt))
973 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
977 sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
979 /* Rule (4): if hole beyond high_sacked */
982 ASSERT (seq_geq (hole->start, sb->high_sacked));
985 /* HighRxt MUST NOT be updated */
990 if (hole && seq_lt (sb->high_rxt, hole->start))
991 sb->high_rxt = hole->start;
997 scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una)
999 sack_scoreboard_hole_t *hole;
1000 hole = scoreboard_first_hole (sb);
1003 snd_una = seq_gt (snd_una, hole->start) ? snd_una : hole->start;
1004 sb->cur_rxt_hole = sb->head;
1006 sb->high_rxt = snd_una;
1007 sb->rescue_rxt = snd_una - 1;
1011 scoreboard_init (sack_scoreboard_t * sb)
1013 sb->head = TCP_INVALID_SACK_HOLE_INDEX;
1014 sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
1015 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
1019 scoreboard_clear (sack_scoreboard_t * sb)
1021 sack_scoreboard_hole_t *hole;
1022 while ((hole = scoreboard_first_hole (sb)))
1024 scoreboard_remove_hole (sb, hole);
1026 ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
1027 ASSERT (pool_elts (sb->holes) == 0);
1028 sb->sacked_bytes = 0;
1029 sb->last_sacked_bytes = 0;
1030 sb->last_bytes_delivered = 0;
1032 sb->last_lost_bytes = 0;
1033 sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
1034 sb->is_reneging = 0;
1038 scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end)
1040 sack_scoreboard_hole_t *last_hole;
1042 clib_warning ("sack reneging");
1044 scoreboard_clear (sb);
1045 last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1047 last_hole->is_lost = 1;
1048 sb->tail = scoreboard_hole_index (sb, last_hole);
1049 sb->high_sacked = start;
1050 scoreboard_init_rxt (sb, start);
1053 #endif /* CLIB_MARCH_VARIANT */
1056 * Test that scoreboard is sane after recovery
1058 * Returns 1 if scoreboard is empty or if first hole beyond
1062 tcp_scoreboard_is_sane_post_recovery (tcp_connection_t * tc)
1064 sack_scoreboard_hole_t *hole;
1065 hole = scoreboard_first_hole (&tc->sack_sb);
1066 return (!hole || (seq_geq (hole->start, tc->snd_una)
1067 && seq_lt (hole->end, tc->snd_nxt)));
1070 #ifndef CLIB_MARCH_VARIANT
1073 tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
1075 sack_scoreboard_hole_t *hole, *next_hole;
1076 sack_scoreboard_t *sb = &tc->sack_sb;
1077 sack_block_t *blk, *rcv_sacks;
1078 u32 blk_index = 0, i, j;
1081 sb->last_sacked_bytes = 0;
1082 sb->last_bytes_delivered = 0;
1085 if (!tcp_opts_sack (&tc->rcv_opts) && !sb->sacked_bytes
1086 && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1089 has_rxt = tcp_in_cong_recovery (tc);
1091 /* Remove invalid blocks */
1092 blk = tc->rcv_opts.sacks;
1093 while (blk < vec_end (tc->rcv_opts.sacks))
1095 if (seq_lt (blk->start, blk->end)
1096 && seq_gt (blk->start, tc->snd_una)
1097 && seq_gt (blk->start, ack) && seq_leq (blk->end, tc->snd_nxt))
1102 vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
1105 /* Add block for cumulative ack */
1106 if (seq_gt (ack, tc->snd_una))
1108 vec_add2 (tc->rcv_opts.sacks, blk, 1);
1109 blk->start = tc->snd_una;
1113 if (vec_len (tc->rcv_opts.sacks) == 0)
1116 tcp_scoreboard_trace_add (tc, ack);
1118 /* Make sure blocks are ordered */
1119 rcv_sacks = tc->rcv_opts.sacks;
1120 for (i = 0; i < vec_len (rcv_sacks); i++)
1121 for (j = i + 1; j < vec_len (rcv_sacks); j++)
1122 if (seq_lt (rcv_sacks[j].start, rcv_sacks[i].start))
1124 sack_block_t tmp = rcv_sacks[i];
1125 rcv_sacks[i] = rcv_sacks[j];
1129 if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
1131 /* Handle reneging as a special case */
1132 if (PREDICT_FALSE (sb->is_reneging))
1134 /* No holes, only sacked bytes */
1135 if (seq_leq (tc->snd_nxt, sb->high_sacked))
1137 /* No progress made so return */
1138 if (seq_leq (ack, tc->snd_una))
1141 /* Update sacked bytes delivered and return */
1142 sb->last_bytes_delivered = ack - tc->snd_una;
1143 sb->sacked_bytes -= sb->last_bytes_delivered;
1144 sb->is_reneging = seq_lt (ack, sb->high_sacked);
1148 /* New hole above high sacked. Add it and process normally */
1149 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1150 sb->high_sacked, tc->snd_nxt);
1151 sb->tail = scoreboard_hole_index (sb, hole);
1153 /* Not reneging and no holes. Insert the first that covers all
1154 * outstanding bytes */
1157 hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
1158 tc->snd_una, tc->snd_nxt);
1159 sb->tail = scoreboard_hole_index (sb, hole);
1161 sb->high_sacked = rcv_sacks[vec_len (rcv_sacks) - 1].end;
1165 /* If we have holes but snd_nxt is beyond the last hole, update
1166 * last hole end or add new hole after high sacked */
1167 hole = scoreboard_last_hole (sb);
1168 if (seq_gt (tc->snd_nxt, hole->end))
1170 if (seq_geq (hole->start, sb->high_sacked))
1172 hole->end = tc->snd_nxt;
1174 /* New hole after high sacked block */
1175 else if (seq_lt (sb->high_sacked, tc->snd_nxt))
1177 scoreboard_insert_hole (sb, sb->tail, sb->high_sacked,
1182 /* Keep track of max byte sacked for when the last hole
1184 sb->high_sacked = seq_max (rcv_sacks[vec_len (rcv_sacks) - 1].end,
1188 /* Walk the holes with the SACK blocks */
1189 hole = pool_elt_at_index (sb->holes, sb->head);
1191 if (PREDICT_FALSE (sb->is_reneging))
1193 sb->last_bytes_delivered += clib_min (hole->start - tc->snd_una,
1195 sb->is_reneging = seq_lt (ack, hole->start);
1198 while (hole && blk_index < vec_len (rcv_sacks))
1200 blk = &rcv_sacks[blk_index];
1201 if (seq_leq (blk->start, hole->start))
1203 /* Block covers hole. Remove hole */
1204 if (seq_geq (blk->end, hole->end))
1206 next_hole = scoreboard_next_hole (sb, hole);
1208 /* If covered by ack, compute delivered bytes */
1209 if (blk->end == ack)
1211 u32 sacked = next_hole ? next_hole->start : sb->high_sacked;
1212 if (PREDICT_FALSE (seq_lt (ack, sacked)))
1214 sb->last_bytes_delivered += ack - hole->end;
1215 sb->is_reneging = 1;
1219 sb->last_bytes_delivered += sacked - hole->end;
1220 sb->is_reneging = 0;
1223 scoreboard_update_sacked_rxt (sb, hole->start, hole->end,
1225 scoreboard_remove_hole (sb, hole);
1228 /* Partial 'head' overlap */
1231 if (seq_gt (blk->end, hole->start))
1233 scoreboard_update_sacked_rxt (sb, hole->start, blk->end,
1235 hole->start = blk->end;
1242 /* Hole must be split */
1243 if (seq_lt (blk->end, hole->end))
1245 u32 hole_index = scoreboard_hole_index (sb, hole);
1246 next_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
1248 /* Pool might've moved */
1249 hole = scoreboard_get_hole (sb, hole_index);
1250 hole->end = blk->start;
1252 scoreboard_update_sacked_rxt (sb, blk->start, blk->end,
1256 ASSERT (hole->next == scoreboard_hole_index (sb, next_hole));
1258 else if (seq_lt (blk->start, hole->end))
1260 scoreboard_update_sacked_rxt (sb, blk->start, hole->end,
1262 hole->end = blk->start;
1264 hole = scoreboard_next_hole (sb, hole);
1268 scoreboard_update_bytes (sb, ack, tc->snd_mss);
1270 ASSERT (sb->last_sacked_bytes <= sb->sacked_bytes || tcp_in_recovery (tc));
1271 ASSERT (sb->sacked_bytes == 0 || tcp_in_recovery (tc)
1272 || sb->sacked_bytes <= tc->snd_nxt - seq_max (tc->snd_una, ack));
1273 ASSERT (sb->last_sacked_bytes + sb->lost_bytes <= tc->snd_nxt
1274 - seq_max (tc->snd_una, ack) || tcp_in_recovery (tc));
1275 ASSERT (sb->head == TCP_INVALID_SACK_HOLE_INDEX || tcp_in_recovery (tc)
1276 || sb->is_reneging || sb->holes[sb->head].start == ack);
1277 ASSERT (sb->last_lost_bytes <= sb->lost_bytes);
1278 ASSERT ((ack - tc->snd_una) + sb->last_sacked_bytes
1279 - sb->last_bytes_delivered >= sb->rxt_sacked);
1280 ASSERT ((ack - tc->snd_una) >= tc->sack_sb.last_bytes_delivered
1281 || (tc->flags & TCP_CONN_FINSNT));
1283 TCP_EVT (TCP_EVT_CC_SCOREBOARD, tc);
1285 #endif /* CLIB_MARCH_VARIANT */
1288 * Try to update snd_wnd based on feedback received from peer.
1290 * If successful, and new window is 'effectively' 0, activate persist
1294 tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
1296 /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
1297 * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
1298 if (seq_lt (tc->snd_wl1, seq)
1299 || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
1301 tc->snd_wnd = snd_wnd;
1304 TCP_EVT (TCP_EVT_SND_WND, tc);
1306 if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
1308 /* Set persist timer if not set and we just got 0 wnd */
1309 if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
1310 && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
1311 tcp_persist_timer_set (tc);
1315 tcp_persist_timer_reset (tc);
1316 if (PREDICT_FALSE (!tcp_in_recovery (tc) && tc->rto_boff > 0))
1319 tcp_update_rto (tc);
1326 * Init loss recovery/fast recovery.
1328 * Triggered by dup acks as opposed to timer timeout. Note that cwnd is
1329 * updated in @ref tcp_cc_handle_event after fast retransmit
1332 tcp_cc_init_congestion (tcp_connection_t * tc)
1334 tcp_fastrecovery_on (tc);
1335 tc->snd_congestion = tc->snd_nxt;
1336 tc->cwnd_acc_bytes = 0;
1337 tc->snd_rxt_bytes = 0;
1338 tc->rxt_delivered = 0;
1339 tc->prr_delivered = 0;
1340 tc->prr_start = tc->snd_una;
1341 tc->prev_ssthresh = tc->ssthresh;
1342 tc->prev_cwnd = tc->cwnd;
1344 tc->snd_rxt_ts = tcp_tstamp (tc);
1345 tcp_cc_congestion (tc);
1347 /* Post retransmit update cwnd to ssthresh and account for the
1348 * three segments that have left the network and should've been
1349 * buffered at the receiver XXX */
1350 if (!tcp_opts_sack_permitted (&tc->rcv_opts))
1351 tc->cwnd += 3 * tc->snd_mss;
1353 tc->fr_occurences += 1;
1354 TCP_EVT (TCP_EVT_CC_EVT, tc, 4);
1358 tcp_cc_congestion_undo (tcp_connection_t * tc)
1360 tc->cwnd = tc->prev_cwnd;
1361 tc->ssthresh = tc->prev_ssthresh;
1362 tcp_cc_undo_recovery (tc);
1363 ASSERT (tc->rto_boff == 0);
1364 TCP_EVT (TCP_EVT_CC_EVT, tc, 5);
1368 tcp_cc_is_spurious_timeout_rxt (tcp_connection_t * tc)
1370 return (tcp_in_recovery (tc) && tc->rto_boff == 1
1372 && tcp_opts_tstamp (&tc->rcv_opts)
1373 && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
1377 tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
1379 return (tcp_cc_is_spurious_timeout_rxt (tc));
1383 tcp_should_fastrecover_sack (tcp_connection_t * tc)
1385 return (tc->sack_sb.lost_bytes
1386 || ((TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
1387 < tc->sack_sb.sacked_bytes));
1391 tcp_should_fastrecover (tcp_connection_t * tc, u8 has_sack)
1395 /* If of of the two conditions lower hold, reset dupacks because
1396 * we're probably after timeout (RFC6582 heuristics).
1397 * If Cumulative ack does not cover more than congestion threshold,
1399 * 1) The following doesn't hold: The congestion window is greater
1400 * than SMSS bytes and the difference between highest_ack
1401 * and prev_highest_ack is at most 4*SMSS bytes
1402 * 2) Echoed timestamp in the last non-dup ack does not equal the
1405 if (seq_leq (tc->snd_una, tc->snd_congestion)
1406 && ((!(tc->cwnd > tc->snd_mss
1407 && tc->bytes_acked <= 4 * tc->snd_mss))
1408 || (tc->rcv_opts.tsecr != tc->tsecr_last_ack)))
1410 tc->rcv_dupacks = 0;
1414 return ((tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1415 || tcp_should_fastrecover_sack (tc));
1419 tcp_cc_recover (tcp_connection_t * tc)
1421 sack_scoreboard_hole_t *hole;
1424 ASSERT (tcp_in_cong_recovery (tc));
1426 if (tcp_cc_is_spurious_retransmit (tc))
1428 tcp_cc_congestion_undo (tc);
1432 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1433 tc->rcv_dupacks = 0;
1435 /* Previous recovery left us congested. Continue sending as part
1436 * of the current recovery event with an updated snd_congestion */
1437 if (tc->sack_sb.sacked_bytes)
1439 tc->snd_congestion = tc->snd_nxt;
1440 tcp_program_retransmit (tc);
1444 tc->rxt_delivered = 0;
1445 tc->snd_rxt_bytes = 0;
1447 tc->prr_delivered = 0;
1449 tc->flags &= ~TCP_CONN_RXT_PENDING;
1451 hole = scoreboard_first_hole (&tc->sack_sb);
1452 if (hole && hole->start == tc->snd_una && hole->end == tc->snd_nxt)
1453 scoreboard_clear (&tc->sack_sb);
1455 if (!tcp_in_recovery (tc) && !is_spurious)
1456 tcp_cc_recovered (tc);
1458 tcp_fastrecovery_off (tc);
1459 tcp_fastrecovery_first_off (tc);
1460 tcp_recovery_off (tc);
1461 TCP_EVT (TCP_EVT_CC_EVT, tc, 3);
1463 ASSERT (tc->rto_boff == 0);
1464 ASSERT (!tcp_in_cong_recovery (tc));
1465 ASSERT (tcp_scoreboard_is_sane_post_recovery (tc));
1470 tcp_cc_update (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1472 ASSERT (!tcp_in_cong_recovery (tc) || tcp_is_lost_fin (tc));
1474 /* Congestion avoidance */
1475 tcp_cc_rcv_ack (tc, rs);
1477 /* If a cumulative ack, make sure dupacks is 0 */
1478 tc->rcv_dupacks = 0;
1480 /* When dupacks hits the threshold we only enter fast retransmit if
1481 * cumulative ack covers more than snd_congestion. Should snd_una
1482 * wrap this test may fail under otherwise valid circumstances.
1483 * Therefore, proactively update snd_congestion when wrap detected. */
1485 (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
1486 && seq_gt (tc->snd_congestion, tc->snd_una)))
1487 tc->snd_congestion = tc->snd_una - 1;
1491 * One function to rule them all ... and in the darkness bind them
1494 tcp_cc_handle_event (tcp_connection_t * tc, tcp_rate_sample_t * rs,
1497 u8 has_sack = tcp_opts_sack_permitted (&tc->rcv_opts);
1499 /* If reneging, wait for timer based retransmits */
1500 if (PREDICT_FALSE (tcp_is_lost_fin (tc) || tc->sack_sb.is_reneging))
1504 * If not in recovery, figure out if we should enter
1506 if (!tcp_in_cong_recovery (tc))
1511 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1512 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1514 if (tcp_should_fastrecover (tc, has_sack))
1516 tcp_cc_init_congestion (tc);
1519 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una);
1521 tcp_connection_tx_pacer_reset (tc, tc->cwnd, 0 /* start bucket */ );
1522 tcp_program_retransmit (tc);
1529 * Already in recovery
1533 * Process (re)transmit feedback. Output path uses this to decide how much
1534 * more data to release into the network
1538 if (!tc->bytes_acked && tc->sack_sb.rxt_sacked)
1539 tcp_fastrecovery_first_on (tc);
1541 tc->rxt_delivered += tc->sack_sb.rxt_sacked;
1542 tc->prr_delivered += tc->bytes_acked + tc->sack_sb.last_sacked_bytes
1543 - tc->sack_sb.last_bytes_delivered;
1545 tcp_program_retransmit (tc);
1551 tc->rcv_dupacks += 1;
1552 TCP_EVT (TCP_EVT_DUPACK_RCVD, tc, 1);
1554 tc->rxt_delivered = clib_min (tc->rxt_delivered + tc->bytes_acked,
1557 tc->prr_delivered += clib_min (tc->snd_mss,
1558 tc->snd_nxt - tc->snd_una);
1560 tc->prr_delivered += tc->bytes_acked - clib_min (tc->bytes_acked,
1564 /* If partial ack, assume that the first un-acked segment was lost */
1565 if (tc->bytes_acked || tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
1566 tcp_fastrecovery_first_on (tc);
1568 tcp_program_retransmit (tc);
1572 * See if we can exit and stop retransmitting
1574 if (seq_geq (tc->snd_una, tc->snd_congestion))
1576 /* If spurious return, we've already updated everything */
1577 if (tcp_cc_recover (tc))
1579 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1583 /* Treat as congestion avoidance ack */
1584 tcp_cc_rcv_ack (tc, rs);
1589 * Notify cc of the event
1592 if (!tc->bytes_acked)
1594 tcp_cc_rcv_cong_ack (tc, TCP_CC_DUPACK, rs);
1598 /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
1599 * reset dupacks to 0. Also needed if in congestion recovery */
1600 tc->rcv_dupacks = 0;
1602 if (tcp_in_recovery (tc))
1603 tcp_cc_rcv_ack (tc, rs);
1605 tcp_cc_rcv_cong_ack (tc, TCP_CC_PARTIALACK, rs);
1609 tcp_handle_old_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1611 if (!tcp_in_cong_recovery (tc))
1614 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1615 tcp_rcv_sacks (tc, tc->snd_una);
1617 tc->bytes_acked = 0;
1619 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1620 tcp_bt_sample_delivery_rate (tc, rs);
1622 tcp_cc_handle_event (tc, rs, 1);
1626 * Check if duplicate ack as per RFC5681 Sec. 2
1629 tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
1632 return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
1633 && seq_gt (tc->snd_nxt, tc->snd_una)
1634 && (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
1635 && (prev_snd_wnd == tc->snd_wnd));
1639 * Checks if ack is a congestion control event.
1642 tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
1643 u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
1645 /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
1646 * defined to be 'duplicate' as well */
1647 *is_dack = tc->sack_sb.last_sacked_bytes
1648 || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
1650 return (*is_dack || tcp_in_cong_recovery (tc));
1654 * Process incoming ACK
1657 tcp_rcv_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1658 tcp_header_t * th, u32 * error)
1660 u32 prev_snd_wnd, prev_snd_una;
1661 tcp_rate_sample_t rs = { 0 };
1664 TCP_EVT (TCP_EVT_CC_STAT, tc);
1666 /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
1667 if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
1669 /* We've probably entered recovery and the peer still has some
1670 * of the data we've sent. Update snd_nxt and accept the ack */
1671 if (seq_leq (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max)
1672 && seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
1674 tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
1678 tc->errors.above_ack_wnd += 1;
1679 *error = TCP_ERROR_ACK_FUTURE;
1680 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 0, vnet_buffer (b)->tcp.ack_number);
1684 /* If old ACK, probably it's an old dupack */
1685 if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
1687 tc->errors.below_ack_wnd += 1;
1688 *error = TCP_ERROR_ACK_OLD;
1689 TCP_EVT (TCP_EVT_ACK_RCV_ERR, tc, 1, vnet_buffer (b)->tcp.ack_number);
1691 if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una - tc->rcv_wnd))
1694 tcp_handle_old_ack (tc, &rs);
1696 /* Don't drop yet */
1703 * Looks okay, process feedback
1706 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1707 tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
1709 prev_snd_wnd = tc->snd_wnd;
1710 prev_snd_una = tc->snd_una;
1711 tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
1712 vnet_buffer (b)->tcp.ack_number,
1713 clib_net_to_host_u16 (th->window) << tc->snd_wscale);
1714 tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
1715 tc->snd_una = vnet_buffer (b)->tcp.ack_number;
1716 tcp_validate_txf_size (tc, tc->bytes_acked);
1718 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1719 tcp_bt_sample_delivery_rate (tc, &rs);
1721 if (tc->bytes_acked)
1723 tcp_program_dequeue (wrk, tc);
1724 tcp_update_rtt (tc, &rs, vnet_buffer (b)->tcp.ack_number);
1727 TCP_EVT (TCP_EVT_ACK_RCVD, tc);
1730 * Check if we have congestion event
1733 if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
1735 tcp_cc_handle_event (tc, &rs, is_dack);
1736 tc->dupacks_in += is_dack;
1737 if (!tcp_in_cong_recovery (tc))
1739 *error = TCP_ERROR_ACK_OK;
1742 *error = TCP_ERROR_ACK_DUP;
1743 if (vnet_buffer (b)->tcp.data_len || tcp_is_fin (th))
1749 * Update congestion control (slow start/congestion avoidance)
1751 tcp_cc_update (tc, &rs);
1752 *error = TCP_ERROR_ACK_OK;
1757 tcp_program_disconnect (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1759 if (!tcp_disconnect_pending (tc))
1761 vec_add1 (wrk->pending_disconnects, tc->c_c_index);
1762 tcp_disconnect_pending_on (tc);
1767 tcp_handle_disconnects (tcp_worker_ctx_t * wrk)
1769 u32 thread_index, *pending_disconnects, *pending_resets;
1770 tcp_connection_t *tc;
1773 if (vec_len (wrk->pending_disconnects))
1775 thread_index = wrk->vm->thread_index;
1776 pending_disconnects = wrk->pending_disconnects;
1777 for (i = 0; i < vec_len (pending_disconnects); i++)
1779 tc = tcp_connection_get (pending_disconnects[i], thread_index);
1780 tcp_disconnect_pending_off (tc);
1781 session_transport_closing_notify (&tc->connection);
1783 _vec_len (wrk->pending_disconnects) = 0;
1786 if (vec_len (wrk->pending_resets))
1788 thread_index = wrk->vm->thread_index;
1789 pending_resets = wrk->pending_resets;
1790 for (i = 0; i < vec_len (pending_resets); i++)
1792 tc = tcp_connection_get (pending_resets[i], thread_index);
1793 tcp_disconnect_pending_off (tc);
1794 tcp_handle_rst (tc);
1796 _vec_len (wrk->pending_resets) = 0;
1801 tcp_rcv_fin (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, vlib_buffer_t * b,
1804 /* Reject out-of-order fins */
1805 if (vnet_buffer (b)->tcp.seq_end != tc->rcv_nxt)
1808 /* Account for the FIN and send ack */
1810 tc->flags |= TCP_CONN_FINRCVD;
1811 tcp_program_ack (tc);
1812 /* Enter CLOSE-WAIT and notify session. To avoid lingering
1813 * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
1814 tcp_connection_set_state (tc, TCP_STATE_CLOSE_WAIT);
1815 tcp_program_disconnect (wrk, tc);
1816 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1817 TCP_EVT (TCP_EVT_FIN_RCVD, tc);
1818 *error = TCP_ERROR_FIN_RCVD;
1821 #ifndef CLIB_MARCH_VARIANT
1823 tcp_sack_vector_is_sane (sack_block_t * sacks)
1826 for (i = 1; i < vec_len (sacks); i++)
1828 if (sacks[i - 1].end == sacks[i].start)
1835 * Build SACK list as per RFC2018.
1837 * Makes sure the first block contains the segment that generated the current
1838 * ACK and the following ones are the ones most recently reported in SACK
1841 * @param tc TCP connection for which the SACK list is updated
1842 * @param start Start sequence number of the newest SACK block
1843 * @param end End sequence of the newest SACK block
1846 tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
1848 sack_block_t *new_list = tc->snd_sacks_fl, *block = 0;
1851 /* If the first segment is ooo add it to the list. Last write might've moved
1852 * rcv_nxt over the first segment. */
1853 if (seq_lt (tc->rcv_nxt, start))
1855 vec_add2 (new_list, block, 1);
1856 block->start = start;
1860 /* Find the blocks still worth keeping. */
1861 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1863 /* Discard if rcv_nxt advanced beyond current block */
1864 if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
1867 /* Merge or drop if segment overlapped by the new segment */
1868 if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
1869 && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
1871 if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
1872 new_list[0].start = tc->snd_sacks[i].start;
1873 if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
1874 new_list[0].end = tc->snd_sacks[i].end;
1878 /* Save to new SACK list if we have space. */
1879 if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
1880 vec_add1 (new_list, tc->snd_sacks[i]);
1883 ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
1885 /* Replace old vector with new one */
1886 vec_reset_length (tc->snd_sacks);
1887 tc->snd_sacks_fl = tc->snd_sacks;
1888 tc->snd_sacks = new_list;
1890 /* Segments should not 'touch' */
1891 ASSERT (tcp_sack_vector_is_sane (tc->snd_sacks));
1895 tcp_sack_list_bytes (tcp_connection_t * tc)
1898 for (i = 0; i < vec_len (tc->snd_sacks); i++)
1899 bytes += tc->snd_sacks[i].end - tc->snd_sacks[i].start;
1902 #endif /* CLIB_MARCH_VARIANT */
1904 /** Enqueue data for delivery to application */
1906 tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
1909 int written, error = TCP_ERROR_ENQUEUED;
1911 ASSERT (seq_geq (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1913 written = session_enqueue_stream_connection (&tc->connection, b, 0,
1914 1 /* queue event */ , 1);
1915 tc->bytes_in += written;
1917 TCP_EVT (TCP_EVT_INPUT, tc, 0, data_len, written);
1919 /* Update rcv_nxt */
1920 if (PREDICT_TRUE (written == data_len))
1922 tc->rcv_nxt += written;
1924 /* If more data written than expected, account for out-of-order bytes. */
1925 else if (written > data_len)
1927 tc->rcv_nxt += written;
1928 TCP_EVT (TCP_EVT_CC_INPUT, tc, data_len, written);
1930 else if (written > 0)
1932 /* We've written something but FIFO is probably full now */
1933 tc->rcv_nxt += written;
1934 error = TCP_ERROR_PARTIALLY_ENQUEUED;
1938 return TCP_ERROR_FIFO_FULL;
1941 /* Update SACK list if need be */
1942 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1944 /* Remove SACK blocks that have been delivered */
1945 tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
1951 /** Enqueue out-of-order data */
1953 tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
1959 ASSERT (seq_gt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt));
1962 /* Enqueue out-of-order data with relative offset */
1963 rv = session_enqueue_stream_connection (&tc->connection, b,
1964 vnet_buffer (b)->tcp.seq_number -
1965 tc->rcv_nxt, 0 /* queue event */ ,
1968 /* Nothing written */
1971 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, 0);
1972 return TCP_ERROR_FIFO_FULL;
1975 TCP_EVT (TCP_EVT_INPUT, tc, 1, data_len, data_len);
1976 tc->bytes_in += data_len;
1978 /* Update SACK list if in use */
1979 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1981 ooo_segment_t *newest;
1984 s0 = session_get (tc->c_s_index, tc->c_thread_index);
1986 /* Get the newest segment from the fifo */
1987 newest = svm_fifo_newest_ooo_segment (s0->rx_fifo);
1990 offset = ooo_segment_offset_prod (s0->rx_fifo, newest);
1991 ASSERT (offset <= vnet_buffer (b)->tcp.seq_number - tc->rcv_nxt);
1992 start = tc->rcv_nxt + offset;
1993 end = start + ooo_segment_length (s0->rx_fifo, newest);
1994 tcp_update_sack_list (tc, start, end);
1995 svm_fifo_newest_ooo_segment_reset (s0->rx_fifo);
1996 TCP_EVT (TCP_EVT_CC_SACKS, tc);
2000 return TCP_ERROR_ENQUEUED_OOO;
2004 * Check if ACK could be delayed. If ack can be delayed, it should return
2005 * true for a full frame. If we're always acking return 0.
2008 tcp_can_delack (tcp_connection_t * tc)
2010 /* Send ack if ... */
2012 /* just sent a rcv wnd 0
2013 || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0 */
2014 /* constrained to send ack */
2015 || (tc->flags & TCP_CONN_SNDACK) != 0
2016 /* we're almost out of tx wnd */
2017 || tcp_available_cc_snd_space (tc) < 4 * tc->snd_mss)
2024 tcp_buffer_discard_bytes (vlib_buffer_t * b, u32 n_bytes_to_drop)
2026 u32 discard, first = b->current_length;
2027 vlib_main_t *vm = vlib_get_main ();
2029 /* Handle multi-buffer segments */
2030 if (n_bytes_to_drop > b->current_length)
2032 if (!(b->flags & VLIB_BUFFER_NEXT_PRESENT))
2036 discard = clib_min (n_bytes_to_drop, b->current_length);
2037 vlib_buffer_advance (b, discard);
2038 b = vlib_get_buffer (vm, b->next_buffer);
2039 n_bytes_to_drop -= discard;
2041 while (n_bytes_to_drop);
2042 if (n_bytes_to_drop > first)
2043 b->total_length_not_including_first_buffer -= n_bytes_to_drop - first;
2046 vlib_buffer_advance (b, n_bytes_to_drop);
2047 vnet_buffer (b)->tcp.data_len -= n_bytes_to_drop;
2052 * Receive buffer for connection and handle acks
2054 * It handles both in order or out-of-order data.
2057 tcp_segment_rcv (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
2060 u32 error, n_bytes_to_drop, n_data_bytes;
2062 vlib_buffer_advance (b, vnet_buffer (b)->tcp.data_offset);
2063 n_data_bytes = vnet_buffer (b)->tcp.data_len;
2064 ASSERT (n_data_bytes);
2065 tc->data_segs_in += 1;
2067 /* Handle out-of-order data */
2068 if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
2070 /* Old sequence numbers allowed through because they overlapped
2072 if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
2074 /* Completely in the past (possible retransmit). Ack
2075 * retransmissions since we may not have any data to send */
2076 if (seq_leq (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
2078 tcp_program_ack (tc);
2079 error = TCP_ERROR_SEGMENT_OLD;
2083 /* Chop off the bytes in the past and see if what is left
2084 * can be enqueued in order */
2085 n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
2086 n_data_bytes -= n_bytes_to_drop;
2087 vnet_buffer (b)->tcp.seq_number = tc->rcv_nxt;
2088 if (tcp_buffer_discard_bytes (b, n_bytes_to_drop))
2090 error = TCP_ERROR_SEGMENT_OLD;
2096 /* RFC2581: Enqueue and send DUPACK for fast retransmit */
2097 error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
2098 tcp_program_dupack (tc);
2099 TCP_EVT (TCP_EVT_DUPACK_SENT, tc, vnet_buffer (b)->tcp);
2100 tc->errors.above_data_wnd += seq_gt (vnet_buffer (b)->tcp.seq_end,
2101 tc->rcv_las + tc->rcv_wnd);
2107 /* In order data, enqueue. Fifo figures out by itself if any out-of-order
2108 * segments can be enqueued after fifo tail offset changes. */
2109 error = tcp_session_enqueue_data (tc, b, n_data_bytes);
2110 if (tcp_can_delack (tc))
2112 if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
2113 tcp_timer_set (tc, TCP_TIMER_DELACK, tcp_cfg.delack_time);
2117 tcp_program_ack (tc);
2125 tcp_header_t tcp_header;
2126 tcp_connection_t tcp_connection;
2130 format_tcp_rx_trace (u8 * s, va_list * args)
2132 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2133 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2134 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2135 tcp_connection_t *tc = &t->tcp_connection;
2136 u32 indent = format_get_indent (s);
2138 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
2139 format_tcp_state, tc->state, format_white_space, indent,
2140 format_tcp_header, &t->tcp_header, 128);
2146 format_tcp_rx_trace_short (u8 * s, va_list * args)
2148 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2149 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2150 tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
2152 s = format (s, "%d -> %d (%U)",
2153 clib_net_to_host_u16 (t->tcp_header.dst_port),
2154 clib_net_to_host_u16 (t->tcp_header.src_port), format_tcp_state,
2155 t->tcp_connection.state);
2161 tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
2162 tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
2166 clib_memcpy_fast (&t0->tcp_connection, tc0,
2167 sizeof (t0->tcp_connection));
2171 th0 = tcp_buffer_hdr (b0);
2173 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
2177 tcp_established_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2178 vlib_frame_t * frame, u8 is_ip4)
2182 n_left = frame->n_vectors;
2183 from = vlib_frame_vector_args (frame);
2187 tcp_connection_t *tc0;
2194 b0 = vlib_get_buffer (vm, bi0);
2196 if (b0->flags & VLIB_BUFFER_IS_TRACED)
2198 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2199 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2201 th0 = tcp_buffer_hdr (b0);
2202 tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
2211 tcp_node_inc_counter_i (vlib_main_t * vm, u32 tcp4_node, u32 tcp6_node,
2212 u8 is_ip4, u32 evt, u32 val)
2215 vlib_node_increment_counter (vm, tcp4_node, evt, val);
2217 vlib_node_increment_counter (vm, tcp6_node, evt, val);
2220 #define tcp_maybe_inc_counter(node_id, err, count) \
2222 if (next0 != tcp_next_drop (is_ip4)) \
2223 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2224 tcp6_##node_id##_node.index, is_ip4, err, \
2227 #define tcp_inc_counter(node_id, err, count) \
2228 tcp_node_inc_counter_i (vm, tcp4_##node_id##_node.index, \
2229 tcp6_##node_id##_node.index, is_ip4, \
2231 #define tcp_maybe_inc_err_counter(cnts, err) \
2233 cnts[err] += (next0 != tcp_next_drop (is_ip4)); \
2235 #define tcp_inc_err_counter(cnts, err, val) \
2239 #define tcp_store_err_counters(node_id, cnts) \
2242 for (i = 0; i < TCP_N_ERROR; i++) \
2244 tcp_inc_counter(node_id, i, cnts[i]); \
2249 tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2250 vlib_frame_t * frame, int is_ip4)
2252 u32 thread_index = vm->thread_index, errors = 0;
2253 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2254 u32 n_left_from, *from, *first_buffer;
2255 u16 err_counters[TCP_N_ERROR] = { 0 };
2257 if (node->flags & VLIB_NODE_FLAG_TRACE)
2258 tcp_established_trace_frame (vm, node, frame, is_ip4);
2260 first_buffer = from = vlib_frame_vector_args (frame);
2261 n_left_from = frame->n_vectors;
2263 while (n_left_from > 0)
2265 u32 bi0, error0 = TCP_ERROR_ACK_OK;
2268 tcp_connection_t *tc0;
2270 if (n_left_from > 1)
2273 pb = vlib_get_buffer (vm, from[1]);
2274 vlib_prefetch_buffer_header (pb, LOAD);
2275 CLIB_PREFETCH (pb->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
2282 b0 = vlib_get_buffer (vm, bi0);
2283 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2286 if (PREDICT_FALSE (tc0 == 0))
2288 error0 = TCP_ERROR_INVALID_CONNECTION;
2292 th0 = tcp_buffer_hdr (b0);
2294 /* TODO header prediction fast path */
2296 /* 1-4: check SEQ, RST, SYN */
2297 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, th0, &error0)))
2299 TCP_EVT (TCP_EVT_SEG_INVALID, tc0, vnet_buffer (b0)->tcp);
2303 /* 5: check the ACK field */
2304 if (PREDICT_FALSE (tcp_rcv_ack (wrk, tc0, b0, th0, &error0)))
2307 /* 6: check the URG bit TODO */
2309 /* 7: process the segment text */
2310 if (vnet_buffer (b0)->tcp.data_len)
2311 error0 = tcp_segment_rcv (wrk, tc0, b0);
2313 /* 8: check the FIN bit */
2314 if (PREDICT_FALSE (tcp_is_fin (th0)))
2315 tcp_rcv_fin (wrk, tc0, b0, &error0);
2318 tcp_inc_err_counter (err_counters, error0, 1);
2321 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2323 err_counters[TCP_ERROR_MSG_QUEUE_FULL] = errors;
2324 tcp_store_err_counters (established, err_counters);
2325 tcp_handle_postponed_dequeues (wrk);
2326 tcp_handle_disconnects (wrk);
2327 vlib_buffer_free (vm, first_buffer, frame->n_vectors);
2329 return frame->n_vectors;
2332 VLIB_NODE_FN (tcp4_established_node) (vlib_main_t * vm,
2333 vlib_node_runtime_t * node,
2334 vlib_frame_t * from_frame)
2336 return tcp46_established_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2339 VLIB_NODE_FN (tcp6_established_node) (vlib_main_t * vm,
2340 vlib_node_runtime_t * node,
2341 vlib_frame_t * from_frame)
2343 return tcp46_established_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2347 VLIB_REGISTER_NODE (tcp4_established_node) =
2349 .name = "tcp4-established",
2350 /* Takes a vector of packets. */
2351 .vector_size = sizeof (u32),
2352 .n_errors = TCP_N_ERROR,
2353 .error_strings = tcp_error_strings,
2354 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2357 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2358 foreach_tcp_state_next
2361 .format_trace = format_tcp_rx_trace_short,
2366 VLIB_REGISTER_NODE (tcp6_established_node) =
2368 .name = "tcp6-established",
2369 /* Takes a vector of packets. */
2370 .vector_size = sizeof (u32),
2371 .n_errors = TCP_N_ERROR,
2372 .error_strings = tcp_error_strings,
2373 .n_next_nodes = TCP_ESTABLISHED_N_NEXT,
2376 #define _(s,n) [TCP_ESTABLISHED_NEXT_##s] = n,
2377 foreach_tcp_state_next
2380 .format_trace = format_tcp_rx_trace_short,
2386 tcp_lookup_is_valid (tcp_connection_t * tc, vlib_buffer_t * b,
2389 transport_connection_t *tmp = 0;
2396 if (tc->c_lcl_port == 0 && tc->state == TCP_STATE_LISTEN)
2399 u8 is_ip_valid = 0, val_l, val_r;
2401 if (tc->connection.is_ip4)
2403 ip4_header_t *ip4_hdr = (ip4_header_t *) vlib_buffer_get_current (b);
2405 val_l = !ip4_address_compare (&ip4_hdr->dst_address,
2406 &tc->connection.lcl_ip.ip4);
2407 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 1);
2408 val_r = !ip4_address_compare (&ip4_hdr->src_address,
2409 &tc->connection.rmt_ip.ip4);
2410 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2411 is_ip_valid = val_l && val_r;
2415 ip6_header_t *ip6_hdr = (ip6_header_t *) vlib_buffer_get_current (b);
2417 val_l = !ip6_address_compare (&ip6_hdr->dst_address,
2418 &tc->connection.lcl_ip.ip6);
2419 val_l = val_l || ip_is_zero (&tc->connection.lcl_ip, 0);
2420 val_r = !ip6_address_compare (&ip6_hdr->src_address,
2421 &tc->connection.rmt_ip.ip6);
2422 val_r = val_r || tc->state == TCP_STATE_LISTEN;
2423 is_ip_valid = val_l && val_r;
2426 u8 is_valid = (tc->c_lcl_port == hdr->dst_port
2427 && (tc->state == TCP_STATE_LISTEN
2428 || tc->c_rmt_port == hdr->src_port) && is_ip_valid);
2432 handle = session_lookup_half_open_handle (&tc->connection);
2433 tmp = session_lookup_half_open_connection (handle & 0xFFFFFFFF,
2434 tc->c_proto, tc->c_is_ip4);
2438 if (tmp->lcl_port == hdr->dst_port
2439 && tmp->rmt_port == hdr->src_port)
2441 TCP_DBG ("half-open is valid!");
2450 * Lookup transport connection
2452 static tcp_connection_t *
2453 tcp_lookup_connection (u32 fib_index, vlib_buffer_t * b, u8 thread_index,
2457 transport_connection_t *tconn;
2458 tcp_connection_t *tc;
2463 ip4 = vlib_buffer_get_current (b);
2464 tcp = ip4_next_header (ip4);
2465 tconn = session_lookup_connection_wt4 (fib_index,
2470 TRANSPORT_PROTO_TCP,
2471 thread_index, &is_filtered);
2472 tc = tcp_get_connection_from_transport (tconn);
2473 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2478 ip6 = vlib_buffer_get_current (b);
2479 tcp = ip6_next_header (ip6);
2480 tconn = session_lookup_connection_wt6 (fib_index,
2485 TRANSPORT_PROTO_TCP,
2486 thread_index, &is_filtered);
2487 tc = tcp_get_connection_from_transport (tconn);
2488 ASSERT (tcp_lookup_is_valid (tc, b, tcp));
2493 static tcp_connection_t *
2494 tcp_lookup_listener (vlib_buffer_t * b, u32 fib_index, int is_ip4)
2500 ip4_header_t *ip4 = vlib_buffer_get_current (b);
2501 tcp_header_t *tcp = tcp_buffer_hdr (b);
2502 s = session_lookup_listener4 (fib_index,
2504 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
2508 ip6_header_t *ip6 = vlib_buffer_get_current (b);
2509 tcp_header_t *tcp = tcp_buffer_hdr (b);
2510 s = session_lookup_listener6 (fib_index,
2512 tcp->dst_port, TRANSPORT_PROTO_TCP, 1);
2515 if (PREDICT_TRUE (s != 0))
2516 return tcp_get_connection_from_transport (transport_get_listener
2517 (TRANSPORT_PROTO_TCP,
2518 s->connection_index));
2524 tcp_check_tx_offload (tcp_connection_t * tc, int is_ipv4)
2526 vnet_main_t *vnm = vnet_get_main ();
2527 const dpo_id_t *dpo;
2528 const load_balance_t *lb;
2529 vnet_hw_interface_t *hw_if;
2530 u32 sw_if_idx, lb_idx;
2534 ip4_address_t *dst_addr = &(tc->c_rmt_ip.ip4);
2535 lb_idx = ip4_fib_forwarding_lookup (tc->c_fib_index, dst_addr);
2539 ip6_address_t *dst_addr = &(tc->c_rmt_ip.ip6);
2540 lb_idx = ip6_fib_table_fwding_lookup (tc->c_fib_index, dst_addr);
2543 lb = load_balance_get (lb_idx);
2544 if (PREDICT_FALSE (lb->lb_n_buckets > 1))
2546 dpo = load_balance_get_bucket_i (lb, 0);
2548 sw_if_idx = dpo_get_urpf (dpo);
2549 if (PREDICT_FALSE (sw_if_idx == ~0))
2552 hw_if = vnet_get_sup_hw_interface (vnm, sw_if_idx);
2553 if (hw_if->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
2554 tc->cfg_flags |= TCP_CFG_F_TSO;
2558 tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2559 vlib_frame_t * from_frame, int is_ip4)
2561 u32 n_left_from, *from, *first_buffer, errors = 0;
2562 u32 my_thread_index = vm->thread_index;
2563 tcp_worker_ctx_t *wrk = tcp_get_worker (my_thread_index);
2565 from = first_buffer = vlib_frame_vector_args (from_frame);
2566 n_left_from = from_frame->n_vectors;
2568 while (n_left_from > 0)
2570 u32 bi0, ack0, seq0, error0 = TCP_ERROR_NONE;
2571 tcp_connection_t *tc0, *new_tc0;
2572 tcp_header_t *tcp0 = 0;
2580 b0 = vlib_get_buffer (vm, bi0);
2582 tcp_half_open_connection_get (vnet_buffer (b0)->tcp.connection_index);
2583 if (PREDICT_FALSE (tc0 == 0))
2585 error0 = TCP_ERROR_INVALID_CONNECTION;
2589 /* Half-open completed recently but the connection was't removed
2590 * yet by the owning thread */
2591 if (PREDICT_FALSE (tc0->flags & TCP_CONN_HALF_OPEN_DONE))
2593 /* Make sure the connection actually exists */
2594 ASSERT (tcp_lookup_connection (tc0->c_fib_index, b0,
2595 my_thread_index, is_ip4));
2596 error0 = TCP_ERROR_SPURIOUS_SYN_ACK;
2600 ack0 = vnet_buffer (b0)->tcp.ack_number;
2601 seq0 = vnet_buffer (b0)->tcp.seq_number;
2602 tcp0 = tcp_buffer_hdr (b0);
2604 /* Crude check to see if the connection handle does not match
2605 * the packet. Probably connection just switched to established */
2606 if (PREDICT_FALSE (tcp0->dst_port != tc0->c_lcl_port
2607 || tcp0->src_port != tc0->c_rmt_port))
2609 error0 = TCP_ERROR_INVALID_CONNECTION;
2613 if (PREDICT_FALSE (!tcp_ack (tcp0) && !tcp_rst (tcp0)
2614 && !tcp_syn (tcp0)))
2616 error0 = TCP_ERROR_SEGMENT_INVALID;
2620 /* SYNs consume sequence numbers */
2621 vnet_buffer (b0)->tcp.seq_end += tcp_is_syn (tcp0);
2624 * 1. check the ACK bit
2628 * If the ACK bit is set
2629 * If SEG.ACK =< ISS, or SEG.ACK > SND.NXT, send a reset (unless
2630 * the RST bit is set, if so drop the segment and return)
2631 * <SEQ=SEG.ACK><CTL=RST>
2632 * and discard the segment. Return.
2633 * If SND.UNA =< SEG.ACK =< SND.NXT then the ACK is acceptable.
2637 if (seq_leq (ack0, tc0->iss) || seq_gt (ack0, tc0->snd_nxt))
2639 if (!tcp_rst (tcp0))
2640 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2641 error0 = TCP_ERROR_RCV_WND;
2645 /* Make sure ACK is valid */
2646 if (seq_gt (tc0->snd_una, ack0))
2648 error0 = TCP_ERROR_ACK_INVALID;
2654 * 2. check the RST bit
2659 /* If ACK is acceptable, signal client that peer is not
2660 * willing to accept connection and drop connection*/
2662 tcp_rcv_rst (wrk, tc0);
2663 error0 = TCP_ERROR_RST_RCVD;
2668 * 3. check the security and precedence (skipped)
2672 * 4. check the SYN bit
2675 /* No SYN flag. Drop. */
2676 if (!tcp_syn (tcp0))
2678 error0 = TCP_ERROR_SEGMENT_INVALID;
2683 if (tcp_options_parse (tcp0, &tc0->rcv_opts, 1))
2685 error0 = TCP_ERROR_OPTIONS;
2689 /* Valid SYN or SYN-ACK. Move connection from half-open pool to
2690 * current thread pool. */
2691 new_tc0 = tcp_connection_alloc_w_base (my_thread_index, tc0);
2692 new_tc0->rcv_nxt = vnet_buffer (b0)->tcp.seq_end;
2693 new_tc0->irs = seq0;
2694 new_tc0->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
2695 new_tc0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
2697 /* If this is not the owning thread, wait for syn retransmit to
2698 * expire and cleanup then */
2699 if (tcp_half_open_connection_cleanup (tc0))
2700 tc0->flags |= TCP_CONN_HALF_OPEN_DONE;
2702 if (tcp_opts_tstamp (&new_tc0->rcv_opts))
2704 new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
2705 new_tc0->tsval_recent_age = tcp_time_now ();
2708 if (tcp_opts_wscale (&new_tc0->rcv_opts))
2709 new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
2711 new_tc0->rcv_wscale = 0;
2713 new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2714 << new_tc0->snd_wscale;
2715 new_tc0->snd_wl1 = seq0;
2716 new_tc0->snd_wl2 = ack0;
2718 tcp_connection_init_vars (new_tc0);
2720 /* SYN-ACK: See if we can switch to ESTABLISHED state */
2721 if (PREDICT_TRUE (tcp_ack (tcp0)))
2723 /* Our SYN is ACKed: we have iss < ack = snd_una */
2725 /* TODO Dequeue acknowledged segments if we support Fast Open */
2726 new_tc0->snd_una = ack0;
2727 new_tc0->state = TCP_STATE_ESTABLISHED;
2729 /* Make sure las is initialized for the wnd computation */
2730 new_tc0->rcv_las = new_tc0->rcv_nxt;
2732 /* Notify app that we have connection. If session layer can't
2733 * allocate session send reset */
2734 if (session_stream_connect_notify (&new_tc0->connection, 0))
2736 tcp_send_reset_w_pkt (new_tc0, b0, my_thread_index, is_ip4);
2737 tcp_connection_cleanup (new_tc0);
2738 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2742 new_tc0->tx_fifo_size =
2743 transport_tx_fifo_size (&new_tc0->connection);
2744 /* Update rtt with the syn-ack sample */
2745 tcp_estimate_initial_rtt (new_tc0);
2746 TCP_EVT (TCP_EVT_SYNACK_RCVD, new_tc0);
2747 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2749 /* SYN: Simultaneous open. Change state to SYN-RCVD and send SYN-ACK */
2752 new_tc0->state = TCP_STATE_SYN_RCVD;
2754 /* Notify app that we have connection */
2755 if (session_stream_connect_notify (&new_tc0->connection, 0))
2757 tcp_connection_cleanup (new_tc0);
2758 tcp_send_reset_w_pkt (tc0, b0, my_thread_index, is_ip4);
2759 TCP_EVT (TCP_EVT_RST_SENT, tc0);
2760 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
2764 new_tc0->tx_fifo_size =
2765 transport_tx_fifo_size (&new_tc0->connection);
2766 new_tc0->rtt_ts = 0;
2767 tcp_init_snd_vars (new_tc0);
2768 tcp_send_synack (new_tc0);
2769 error0 = TCP_ERROR_SYNS_RCVD;
2773 if (!(new_tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2774 tcp_check_tx_offload (new_tc0, is_ip4);
2776 /* Read data, if any */
2777 if (PREDICT_FALSE (vnet_buffer (b0)->tcp.data_len))
2779 clib_warning ("rcvd data in syn-sent");
2780 error0 = tcp_segment_rcv (wrk, new_tc0, b0);
2781 if (error0 == TCP_ERROR_ACK_OK)
2782 error0 = TCP_ERROR_SYN_ACKS_RCVD;
2786 /* Send ack now instead of programming it because connection was
2787 * just established and it's not optional. */
2788 tcp_send_ack (new_tc0);
2793 tcp_inc_counter (syn_sent, error0, 1);
2794 if (PREDICT_FALSE ((b0->flags & VLIB_BUFFER_IS_TRACED) && tcp0 != 0))
2796 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2797 clib_memcpy_fast (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
2798 clib_memcpy_fast (&t0->tcp_connection, tc0,
2799 sizeof (t0->tcp_connection));
2803 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
2805 tcp_inc_counter (syn_sent, TCP_ERROR_MSG_QUEUE_FULL, errors);
2806 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
2807 tcp_handle_disconnects (wrk);
2809 return from_frame->n_vectors;
2812 VLIB_NODE_FN (tcp4_syn_sent_node) (vlib_main_t * vm,
2813 vlib_node_runtime_t * node,
2814 vlib_frame_t * from_frame)
2816 return tcp46_syn_sent_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2819 VLIB_NODE_FN (tcp6_syn_sent_node) (vlib_main_t * vm,
2820 vlib_node_runtime_t * node,
2821 vlib_frame_t * from_frame)
2823 return tcp46_syn_sent_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2827 VLIB_REGISTER_NODE (tcp4_syn_sent_node) =
2829 .name = "tcp4-syn-sent",
2830 /* Takes a vector of packets. */
2831 .vector_size = sizeof (u32),
2832 .n_errors = TCP_N_ERROR,
2833 .error_strings = tcp_error_strings,
2834 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2837 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2838 foreach_tcp_state_next
2841 .format_trace = format_tcp_rx_trace_short,
2846 VLIB_REGISTER_NODE (tcp6_syn_sent_node) =
2848 .name = "tcp6-syn-sent",
2849 /* Takes a vector of packets. */
2850 .vector_size = sizeof (u32),
2851 .n_errors = TCP_N_ERROR,
2852 .error_strings = tcp_error_strings,
2853 .n_next_nodes = TCP_SYN_SENT_N_NEXT,
2856 #define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
2857 foreach_tcp_state_next
2860 .format_trace = format_tcp_rx_trace_short,
2865 * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
2866 * as per RFC793 p. 64
2869 tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2870 vlib_frame_t * from_frame, int is_ip4)
2872 u32 thread_index = vm->thread_index, errors = 0, *first_buffer;
2873 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
2874 u32 n_left_from, *from, max_dequeue;
2876 from = first_buffer = vlib_frame_vector_args (from_frame);
2877 n_left_from = from_frame->n_vectors;
2879 while (n_left_from > 0)
2881 u32 bi0, error0 = TCP_ERROR_NONE;
2882 tcp_header_t *tcp0 = 0;
2883 tcp_connection_t *tc0;
2891 b0 = vlib_get_buffer (vm, bi0);
2892 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
2894 if (PREDICT_FALSE (tc0 == 0))
2896 error0 = TCP_ERROR_INVALID_CONNECTION;
2900 tcp0 = tcp_buffer_hdr (b0);
2901 is_fin0 = tcp_is_fin (tcp0);
2905 if (!(tc0->connection.flags & TRANSPORT_CONNECTION_F_NO_LOOKUP))
2907 tcp_connection_t *tmp;
2908 tmp = tcp_lookup_connection (tc0->c_fib_index, b0, thread_index,
2910 if (tmp->state != tc0->state)
2912 if (tc0->state != TCP_STATE_CLOSED)
2913 clib_warning ("state changed");
2920 * Special treatment for CLOSED
2922 if (PREDICT_FALSE (tc0->state == TCP_STATE_CLOSED))
2924 error0 = TCP_ERROR_CONNECTION_CLOSED;
2929 * For all other states (except LISTEN)
2932 /* 1-4: check SEQ, RST, SYN */
2933 if (PREDICT_FALSE (tcp_segment_validate (wrk, tc0, b0, tcp0, &error0)))
2936 /* 5: check the ACK field */
2939 case TCP_STATE_SYN_RCVD:
2941 /* Make sure the segment is exactly right */
2942 if (tc0->rcv_nxt != vnet_buffer (b0)->tcp.seq_number || is_fin0)
2944 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2945 error0 = TCP_ERROR_SEGMENT_INVALID;
2950 * If the segment acknowledgment is not acceptable, form a
2952 * <SEQ=SEG.ACK><CTL=RST>
2955 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
2957 tcp_send_reset_w_pkt (tc0, b0, thread_index, is_ip4);
2958 error0 = TCP_ERROR_SEGMENT_INVALID;
2962 /* Update rtt and rto */
2963 tcp_estimate_initial_rtt (tc0);
2964 tcp_connection_tx_pacer_update (tc0);
2966 /* Switch state to ESTABLISHED */
2967 tc0->state = TCP_STATE_ESTABLISHED;
2968 TCP_EVT (TCP_EVT_STATE_CHANGE, tc0);
2970 if (!(tc0->cfg_flags & TCP_CFG_F_NO_TSO))
2971 tcp_check_tx_offload (tc0, is_ip4);
2973 /* Initialize session variables */
2974 tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
2975 tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
2976 << tc0->rcv_opts.wscale;
2977 tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
2978 tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
2980 /* Reset SYN-ACK retransmit and SYN_RCV establish timers */
2981 tcp_retransmit_timer_reset (tc0);
2982 if (session_stream_accept_notify (&tc0->connection))
2984 error0 = TCP_ERROR_MSG_QUEUE_FULL;
2985 tcp_send_reset (tc0);
2986 session_transport_delete_notify (&tc0->connection);
2987 tcp_connection_cleanup (tc0);
2990 error0 = TCP_ERROR_ACK_OK;
2992 case TCP_STATE_ESTABLISHED:
2993 /* We can get packets in established state here because they
2994 * were enqueued before state change */
2995 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
2999 case TCP_STATE_FIN_WAIT_1:
3000 /* In addition to the processing for the ESTABLISHED state, if
3001 * our FIN is now acknowledged then enter FIN-WAIT-2 and
3002 * continue processing in that state. */
3003 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
3006 /* Still have to send the FIN */
3007 if (tc0->flags & TCP_CONN_FINPNDG)
3009 /* TX fifo finally drained */
3010 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
3011 if (max_dequeue <= tc0->burst_acked)
3013 /* If a fin was received and data was acked extend wait */
3014 else if ((tc0->flags & TCP_CONN_FINRCVD) && tc0->bytes_acked)
3015 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3016 tcp_cfg.closewait_time);
3018 /* If FIN is ACKed */
3019 else if (tc0->snd_una == tc0->snd_nxt)
3021 /* Stop all retransmit timers because we have nothing more
3023 tcp_connection_timers_reset (tc0);
3025 /* We already have a FIN but didn't transition to CLOSING
3026 * because of outstanding tx data. Close the connection. */
3027 if (tc0->flags & TCP_CONN_FINRCVD)
3029 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
3030 session_transport_closed_notify (&tc0->connection);
3031 tcp_program_cleanup (wrk, tc0);
3035 tcp_connection_set_state (tc0, TCP_STATE_FIN_WAIT_2);
3036 /* Enable waitclose because we're willing to wait for peer's
3037 * FIN but not indefinitely. */
3038 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.finwait2_time);
3040 /* Don't try to deq the FIN acked */
3041 if (tc0->burst_acked > 1)
3042 session_tx_fifo_dequeue_drop (&tc0->connection,
3043 tc0->burst_acked - 1);
3044 tc0->burst_acked = 0;
3047 case TCP_STATE_FIN_WAIT_2:
3048 /* In addition to the processing for the ESTABLISHED state, if
3049 * the retransmission queue is empty, the user's CLOSE can be
3050 * acknowledged ("ok") but do not delete the TCB. */
3051 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3053 tc0->burst_acked = 0;
3055 case TCP_STATE_CLOSE_WAIT:
3056 /* Do the same processing as for the ESTABLISHED state. */
3057 if (tcp_rcv_ack (wrk, tc0, b0, tcp0, &error0))
3060 if (!(tc0->flags & TCP_CONN_FINPNDG))
3063 /* Still have outstanding tx data */
3064 max_dequeue = transport_max_tx_dequeue (&tc0->connection);
3065 if (max_dequeue > tc0->burst_acked)
3069 tcp_connection_timers_reset (tc0);
3070 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3071 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3073 case TCP_STATE_CLOSING:
3074 /* In addition to the processing for the ESTABLISHED state, if
3075 * the ACK acknowledges our FIN then enter the TIME-WAIT state,
3076 * otherwise ignore the segment. */
3077 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3080 if (tc0->snd_una != tc0->snd_nxt)
3083 tcp_connection_timers_reset (tc0);
3084 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3085 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3086 session_transport_closed_notify (&tc0->connection);
3090 case TCP_STATE_LAST_ACK:
3091 /* The only thing that [should] arrive in this state is an
3092 * acknowledgment of our FIN. If our FIN is now acknowledged,
3093 * delete the TCB, enter the CLOSED state, and return. */
3095 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3098 /* Apparently our ACK for the peer's FIN was lost */
3099 if (is_fin0 && tc0->snd_una != tc0->snd_nxt)
3105 tcp_connection_set_state (tc0, TCP_STATE_CLOSED);
3106 session_transport_closed_notify (&tc0->connection);
3108 /* Don't free the connection from the data path since
3109 * we can't ensure that we have no packets already enqueued
3110 * to output. Rely instead on the waitclose timer */
3111 tcp_connection_timers_reset (tc0);
3112 tcp_program_cleanup (tcp_get_worker (tc0->c_thread_index), tc0);
3117 case TCP_STATE_TIME_WAIT:
3118 /* The only thing that can arrive in this state is a
3119 * retransmission of the remote FIN. Acknowledge it, and restart
3120 * the 2 MSL timeout. */
3122 if (tcp_rcv_ack_no_cc (tc0, b0, &error0))
3128 tcp_program_ack (tc0);
3129 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3137 /* 6: check the URG bit TODO */
3139 /* 7: process the segment text */
3142 case TCP_STATE_ESTABLISHED:
3143 case TCP_STATE_FIN_WAIT_1:
3144 case TCP_STATE_FIN_WAIT_2:
3145 if (vnet_buffer (b0)->tcp.data_len)
3146 error0 = tcp_segment_rcv (wrk, tc0, b0);
3148 case TCP_STATE_CLOSE_WAIT:
3149 case TCP_STATE_CLOSING:
3150 case TCP_STATE_LAST_ACK:
3151 case TCP_STATE_TIME_WAIT:
3152 /* This should not occur, since a FIN has been received from the
3153 * remote side. Ignore the segment text. */
3157 /* 8: check the FIN bit */
3161 TCP_EVT (TCP_EVT_FIN_RCVD, tc0);
3165 case TCP_STATE_ESTABLISHED:
3166 /* Account for the FIN and send ack */
3168 tcp_program_ack (tc0);
3169 tcp_connection_set_state (tc0, TCP_STATE_CLOSE_WAIT);
3170 tcp_program_disconnect (wrk, tc0);
3171 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
3173 case TCP_STATE_SYN_RCVD:
3174 /* Send FIN-ACK, enter LAST-ACK and because the app was not
3175 * notified yet, set a cleanup timer instead of relying on
3176 * disconnect notify and the implicit close call. */
3177 tcp_connection_timers_reset (tc0);
3180 tcp_connection_set_state (tc0, TCP_STATE_LAST_ACK);
3181 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.lastack_time);
3183 case TCP_STATE_CLOSE_WAIT:
3184 case TCP_STATE_CLOSING:
3185 case TCP_STATE_LAST_ACK:
3188 case TCP_STATE_FIN_WAIT_1:
3191 if (tc0->flags & TCP_CONN_FINPNDG)
3193 /* If data is outstanding, stay in FIN_WAIT_1 and try to finish
3194 * sending it. Since we already received a fin, do not wait
3196 tc0->flags |= TCP_CONN_FINRCVD;
3197 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3198 tcp_cfg.closewait_time);
3202 tcp_connection_set_state (tc0, TCP_STATE_CLOSING);
3203 tcp_program_ack (tc0);
3204 /* Wait for ACK for our FIN but not forever */
3205 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE,
3206 tcp_cfg.closing_time);
3209 case TCP_STATE_FIN_WAIT_2:
3210 /* Got FIN, send ACK! Be more aggressive with resource cleanup */
3212 tcp_connection_set_state (tc0, TCP_STATE_TIME_WAIT);
3213 tcp_connection_timers_reset (tc0);
3214 tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3215 tcp_program_ack (tc0);
3216 session_transport_closed_notify (&tc0->connection);
3218 case TCP_STATE_TIME_WAIT:
3219 /* Remain in the TIME-WAIT state. Restart the time-wait
3222 tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, tcp_cfg.timewait_time);
3225 error0 = TCP_ERROR_FIN_RCVD;
3229 tcp_inc_counter (rcv_process, error0, 1);
3230 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3232 tcp_rx_trace_t *t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3233 tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
3237 errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_TCP,
3239 tcp_inc_counter (rcv_process, TCP_ERROR_MSG_QUEUE_FULL, errors);
3240 tcp_handle_postponed_dequeues (wrk);
3241 tcp_handle_disconnects (wrk);
3242 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3244 return from_frame->n_vectors;
3247 VLIB_NODE_FN (tcp4_rcv_process_node) (vlib_main_t * vm,
3248 vlib_node_runtime_t * node,
3249 vlib_frame_t * from_frame)
3251 return tcp46_rcv_process_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3254 VLIB_NODE_FN (tcp6_rcv_process_node) (vlib_main_t * vm,
3255 vlib_node_runtime_t * node,
3256 vlib_frame_t * from_frame)
3258 return tcp46_rcv_process_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3262 VLIB_REGISTER_NODE (tcp4_rcv_process_node) =
3264 .name = "tcp4-rcv-process",
3265 /* Takes a vector of packets. */
3266 .vector_size = sizeof (u32),
3267 .n_errors = TCP_N_ERROR,
3268 .error_strings = tcp_error_strings,
3269 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3272 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3273 foreach_tcp_state_next
3276 .format_trace = format_tcp_rx_trace_short,
3281 VLIB_REGISTER_NODE (tcp6_rcv_process_node) =
3283 .name = "tcp6-rcv-process",
3284 /* Takes a vector of packets. */
3285 .vector_size = sizeof (u32),
3286 .n_errors = TCP_N_ERROR,
3287 .error_strings = tcp_error_strings,
3288 .n_next_nodes = TCP_RCV_PROCESS_N_NEXT,
3291 #define _(s,n) [TCP_RCV_PROCESS_NEXT_##s] = n,
3292 foreach_tcp_state_next
3295 .format_trace = format_tcp_rx_trace_short,
3300 * LISTEN state processing as per RFC 793 p. 65
3303 tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3304 vlib_frame_t * from_frame, int is_ip4)
3306 u32 n_left_from, *from, n_syns = 0, *first_buffer;
3307 u32 my_thread_index = vm->thread_index;
3308 tcp_connection_t *tc0;
3310 from = first_buffer = vlib_frame_vector_args (from_frame);
3311 n_left_from = from_frame->n_vectors;
3313 while (n_left_from > 0)
3318 tcp_header_t *th0 = 0;
3319 tcp_connection_t *lc0;
3322 tcp_connection_t *child0;
3323 u32 error0 = TCP_ERROR_NONE;
3329 b0 = vlib_get_buffer (vm, bi0);
3333 ip40 = vlib_buffer_get_current (b0);
3334 th0 = tcp_buffer_hdr (b0);
3338 ip60 = vlib_buffer_get_current (b0);
3339 th0 = tcp_buffer_hdr (b0);
3342 lc0 = tcp_listener_get (vnet_buffer (b0)->tcp.connection_index);
3343 if (PREDICT_FALSE (lc0 == 0))
3345 tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
3347 if (tc0->state != TCP_STATE_TIME_WAIT)
3349 error0 = TCP_ERROR_CREATE_EXISTS;
3352 lc0 = tcp_lookup_listener (b0, tc0->c_fib_index, is_ip4);
3353 /* clean up the old session */
3354 tcp_connection_del (tc0);
3357 /* Create child session. For syn-flood protection use filter */
3359 /* 1. first check for an RST: handled in dispatch */
3360 /* if (tcp_rst (th0))
3364 /* 2. second check for an ACK: handled in dispatch */
3365 /* if (tcp_ack (th0))
3367 tcp_send_reset (b0, is_ip4);
3372 /* 3. check for a SYN (did that already) */
3374 /* Make sure connection wasn't just created */
3375 child0 = tcp_lookup_connection (lc0->c_fib_index, b0, my_thread_index,
3377 if (PREDICT_FALSE (child0->state != TCP_STATE_LISTEN))
3379 error0 = TCP_ERROR_CREATE_EXISTS;
3383 /* Create child session and send SYN-ACK */
3384 child0 = tcp_connection_alloc (my_thread_index);
3385 child0->c_lcl_port = th0->dst_port;
3386 child0->c_rmt_port = th0->src_port;
3387 child0->c_is_ip4 = is_ip4;
3388 child0->state = TCP_STATE_SYN_RCVD;
3389 child0->c_fib_index = lc0->c_fib_index;
3390 child0->cc_algo = lc0->cc_algo;
3394 child0->c_lcl_ip4.as_u32 = ip40->dst_address.as_u32;
3395 child0->c_rmt_ip4.as_u32 = ip40->src_address.as_u32;
3399 clib_memcpy_fast (&child0->c_lcl_ip6, &ip60->dst_address,
3400 sizeof (ip6_address_t));
3401 clib_memcpy_fast (&child0->c_rmt_ip6, &ip60->src_address,
3402 sizeof (ip6_address_t));
3405 if (tcp_options_parse (th0, &child0->rcv_opts, 1))
3407 error0 = TCP_ERROR_OPTIONS;
3408 tcp_connection_free (child0);
3412 child0->irs = vnet_buffer (b0)->tcp.seq_number;
3413 child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
3414 child0->rcv_las = child0->rcv_nxt;
3415 child0->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
3417 /* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
3418 * segments are used to initialize PAWS. */
3419 if (tcp_opts_tstamp (&child0->rcv_opts))
3421 child0->tsval_recent = child0->rcv_opts.tsval;
3422 child0->tsval_recent_age = tcp_time_now ();
3425 if (tcp_opts_wscale (&child0->rcv_opts))
3426 child0->snd_wscale = child0->rcv_opts.wscale;
3428 child0->snd_wnd = clib_net_to_host_u16 (th0->window)
3429 << child0->snd_wscale;
3430 child0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
3431 child0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
3433 tcp_connection_init_vars (child0);
3434 child0->rto = TCP_RTO_MIN;
3436 if (session_stream_accept (&child0->connection, lc0->c_s_index,
3437 lc0->c_thread_index, 0 /* notify */ ))
3439 tcp_connection_cleanup (child0);
3440 error0 = TCP_ERROR_CREATE_SESSION_FAIL;
3444 TCP_EVT (TCP_EVT_SYN_RCVD, child0, 1);
3445 child0->tx_fifo_size = transport_tx_fifo_size (&child0->connection);
3446 tcp_send_synack (child0);
3450 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
3452 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
3453 clib_memcpy_fast (&t0->tcp_header, th0, sizeof (t0->tcp_header));
3454 clib_memcpy_fast (&t0->tcp_connection, lc0,
3455 sizeof (t0->tcp_connection));
3458 n_syns += (error0 == TCP_ERROR_NONE);
3461 tcp_inc_counter (listen, TCP_ERROR_SYNS_RCVD, n_syns);
3462 vlib_buffer_free (vm, first_buffer, from_frame->n_vectors);
3464 return from_frame->n_vectors;
3467 VLIB_NODE_FN (tcp4_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3468 vlib_frame_t * from_frame)
3470 return tcp46_listen_inline (vm, node, from_frame, 1 /* is_ip4 */ );
3473 VLIB_NODE_FN (tcp6_listen_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3474 vlib_frame_t * from_frame)
3476 return tcp46_listen_inline (vm, node, from_frame, 0 /* is_ip4 */ );
3480 VLIB_REGISTER_NODE (tcp4_listen_node) =
3482 .name = "tcp4-listen",
3483 /* Takes a vector of packets. */
3484 .vector_size = sizeof (u32),
3485 .n_errors = TCP_N_ERROR,
3486 .error_strings = tcp_error_strings,
3487 .n_next_nodes = TCP_LISTEN_N_NEXT,
3490 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3491 foreach_tcp_state_next
3494 .format_trace = format_tcp_rx_trace_short,
3499 VLIB_REGISTER_NODE (tcp6_listen_node) =
3501 .name = "tcp6-listen",
3502 /* Takes a vector of packets. */
3503 .vector_size = sizeof (u32),
3504 .n_errors = TCP_N_ERROR,
3505 .error_strings = tcp_error_strings,
3506 .n_next_nodes = TCP_LISTEN_N_NEXT,
3509 #define _(s,n) [TCP_LISTEN_NEXT_##s] = n,
3510 foreach_tcp_state_next
3513 .format_trace = format_tcp_rx_trace_short,
3517 typedef enum _tcp_input_next
3519 TCP_INPUT_NEXT_DROP,
3520 TCP_INPUT_NEXT_LISTEN,
3521 TCP_INPUT_NEXT_RCV_PROCESS,
3522 TCP_INPUT_NEXT_SYN_SENT,
3523 TCP_INPUT_NEXT_ESTABLISHED,
3524 TCP_INPUT_NEXT_RESET,
3525 TCP_INPUT_NEXT_PUNT,
3529 #define foreach_tcp4_input_next \
3530 _ (DROP, "ip4-drop") \
3531 _ (LISTEN, "tcp4-listen") \
3532 _ (RCV_PROCESS, "tcp4-rcv-process") \
3533 _ (SYN_SENT, "tcp4-syn-sent") \
3534 _ (ESTABLISHED, "tcp4-established") \
3535 _ (RESET, "tcp4-reset") \
3536 _ (PUNT, "ip4-punt")
3538 #define foreach_tcp6_input_next \
3539 _ (DROP, "ip6-drop") \
3540 _ (LISTEN, "tcp6-listen") \
3541 _ (RCV_PROCESS, "tcp6-rcv-process") \
3542 _ (SYN_SENT, "tcp6-syn-sent") \
3543 _ (ESTABLISHED, "tcp6-established") \
3544 _ (RESET, "tcp6-reset") \
3545 _ (PUNT, "ip6-punt")
3547 #define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
3550 tcp_input_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
3551 vlib_buffer_t ** bs, u32 n_bufs, u8 is_ip4)
3553 tcp_connection_t *tc;
3558 for (i = 0; i < n_bufs; i++)
3560 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
3562 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
3563 tc = tcp_connection_get (vnet_buffer (bs[i])->tcp.connection_index,
3565 tcp = vlib_buffer_get_current (bs[i]);
3566 tcp_set_rx_trace_data (t, tc, tcp, bs[i], is_ip4);
3572 tcp_input_set_error_next (tcp_main_t * tm, u16 * next, u32 * error, u8 is_ip4)
3574 if (*error == TCP_ERROR_FILTERED || *error == TCP_ERROR_WRONG_THREAD)
3576 *next = TCP_INPUT_NEXT_DROP;
3578 else if ((is_ip4 && tm->punt_unknown4) || (!is_ip4 && tm->punt_unknown6))
3580 *next = TCP_INPUT_NEXT_PUNT;
3581 *error = TCP_ERROR_PUNT;
3585 *next = TCP_INPUT_NEXT_RESET;
3586 *error = TCP_ERROR_NO_LISTENER;
3590 always_inline tcp_connection_t *
3591 tcp_input_lookup_buffer (vlib_buffer_t * b, u8 thread_index, u32 * error,
3592 u8 is_ip4, u8 is_nolookup)
3594 u32 fib_index = vnet_buffer (b)->ip.fib_index;
3595 int n_advance_bytes, n_data_bytes;
3596 transport_connection_t *tc;
3602 ip4_header_t *ip4 = vlib_buffer_get_current (b);
3603 int ip_hdr_bytes = ip4_header_bytes (ip4);
3604 if (PREDICT_FALSE (b->current_length < ip_hdr_bytes + sizeof (*tcp)))
3606 *error = TCP_ERROR_LENGTH;
3609 tcp = ip4_next_header (ip4);
3610 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip4;
3611 n_advance_bytes = (ip_hdr_bytes + tcp_header_bytes (tcp));
3612 n_data_bytes = clib_net_to_host_u16 (ip4->length) - n_advance_bytes;
3614 /* Length check. Checksum computed by ipx_local no need to compute again */
3615 if (PREDICT_FALSE (n_data_bytes < 0))
3617 *error = TCP_ERROR_LENGTH;
3622 tc = session_lookup_connection_wt4 (fib_index, &ip4->dst_address,
3623 &ip4->src_address, tcp->dst_port,
3625 TRANSPORT_PROTO_TCP, thread_index,
3630 ip6_header_t *ip6 = vlib_buffer_get_current (b);
3631 if (PREDICT_FALSE (b->current_length < sizeof (*ip6) + sizeof (*tcp)))
3633 *error = TCP_ERROR_LENGTH;
3636 tcp = ip6_next_header (ip6);
3637 vnet_buffer (b)->tcp.hdr_offset = (u8 *) tcp - (u8 *) ip6;
3638 n_advance_bytes = tcp_header_bytes (tcp);
3639 n_data_bytes = clib_net_to_host_u16 (ip6->payload_length)
3641 n_advance_bytes += sizeof (ip6[0]);
3643 if (PREDICT_FALSE (n_data_bytes < 0))
3645 *error = TCP_ERROR_LENGTH;
3652 (ip6_address_is_link_local_unicast (&ip6->dst_address)))
3654 ip4_main_t *im = &ip4_main;
3655 fib_index = vec_elt (im->fib_index_by_sw_if_index,
3656 vnet_buffer (b)->sw_if_index[VLIB_RX]);
3659 tc = session_lookup_connection_wt6 (fib_index, &ip6->dst_address,
3661 tcp->dst_port, tcp->src_port,
3662 TRANSPORT_PROTO_TCP,
3663 thread_index, &result);
3669 (transport_connection_t *) tcp_connection_get (vnet_buffer (b)->
3670 tcp.connection_index,
3673 vnet_buffer (b)->tcp.seq_number = clib_net_to_host_u32 (tcp->seq_number);
3674 vnet_buffer (b)->tcp.ack_number = clib_net_to_host_u32 (tcp->ack_number);
3675 vnet_buffer (b)->tcp.data_offset = n_advance_bytes;
3676 vnet_buffer (b)->tcp.data_len = n_data_bytes;
3677 vnet_buffer (b)->tcp.seq_end = vnet_buffer (b)->tcp.seq_number
3679 vnet_buffer (b)->tcp.flags = 0;
3681 *error = result ? TCP_ERROR_NONE + result : *error;
3683 return tcp_get_connection_from_transport (tc);
3687 tcp_input_dispatch_buffer (tcp_main_t * tm, tcp_connection_t * tc,
3688 vlib_buffer_t * b, u16 * next,
3689 vlib_node_runtime_t * error_node)
3695 tcp = tcp_buffer_hdr (b);
3696 flags = tcp->flags & filter_flags;
3697 *next = tm->dispatch_table[tc->state][flags].next;
3698 error = tm->dispatch_table[tc->state][flags].error;
3701 if (PREDICT_FALSE (error != TCP_ERROR_NONE))
3703 b->error = error_node->errors[error];
3704 if (error == TCP_ERROR_DISPATCH)
3705 clib_warning ("tcp conn %u disp error state %U flags %U",
3706 tc->c_c_index, format_tcp_state, tc->state,
3707 format_tcp_flags, (int) flags);
3712 tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
3713 vlib_frame_t * frame, int is_ip4, u8 is_nolookup)
3715 u32 n_left_from, *from, thread_index = vm->thread_index;
3716 tcp_main_t *tm = vnet_get_tcp_main ();
3717 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
3718 u16 nexts[VLIB_FRAME_SIZE], *next;
3719 vlib_node_runtime_t *error_node;
3721 tcp_set_time_now (tcp_get_worker (thread_index));
3723 error_node = vlib_node_get_runtime (vm, tcp_node_index (input, is_ip4));
3724 from = vlib_frame_vector_args (frame);
3725 n_left_from = frame->n_vectors;
3726 vlib_get_buffers (vm, from, bufs, n_left_from);
3731 while (n_left_from >= 4)
3733 u32 error0 = TCP_ERROR_NO_LISTENER, error1 = TCP_ERROR_NO_LISTENER;
3734 tcp_connection_t *tc0, *tc1;
3737 vlib_prefetch_buffer_header (b[2], STORE);
3738 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3740 vlib_prefetch_buffer_header (b[3], STORE);
3741 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3744 next[0] = next[1] = TCP_INPUT_NEXT_DROP;
3746 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3748 tc1 = tcp_input_lookup_buffer (b[1], thread_index, &error1, is_ip4,
3751 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
3753 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3754 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3756 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3757 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3759 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], error_node);
3760 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], error_node);
3764 if (PREDICT_TRUE (tc0 != 0))
3766 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3767 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3768 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], error_node);
3772 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3773 b[0]->error = error_node->errors[error0];
3776 if (PREDICT_TRUE (tc1 != 0))
3778 ASSERT (tcp_lookup_is_valid (tc1, b[1], tcp_buffer_hdr (b[1])));
3779 vnet_buffer (b[1])->tcp.connection_index = tc1->c_c_index;
3780 tcp_input_dispatch_buffer (tm, tc1, b[1], &next[1], error_node);
3784 tcp_input_set_error_next (tm, &next[1], &error1, is_ip4);
3785 b[1]->error = error_node->errors[error1];
3793 while (n_left_from > 0)
3795 tcp_connection_t *tc0;
3796 u32 error0 = TCP_ERROR_NO_LISTENER;
3798 if (n_left_from > 1)
3800 vlib_prefetch_buffer_header (b[1], STORE);
3801 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
3804 next[0] = TCP_INPUT_NEXT_DROP;
3805 tc0 = tcp_input_lookup_buffer (b[0], thread_index, &error0, is_ip4,
3807 if (PREDICT_TRUE (tc0 != 0))
3809 ASSERT (tcp_lookup_is_valid (tc0, b[0], tcp_buffer_hdr (b[0])));
3810 vnet_buffer (b[0])->tcp.connection_index = tc0->c_c_index;
3811 tcp_input_dispatch_buffer (tm, tc0, b[0], &next[0], error_node);
3815 tcp_input_set_error_next (tm, &next[0], &error0, is_ip4);
3816 b[0]->error = error_node->errors[error0];
3824 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
3825 tcp_input_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
3827 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
3828 return frame->n_vectors;
3831 VLIB_NODE_FN (tcp4_input_nolookup_node) (vlib_main_t * vm,
3832 vlib_node_runtime_t * node,
3833 vlib_frame_t * from_frame)
3835 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3836 1 /* is_nolookup */ );
3839 VLIB_NODE_FN (tcp6_input_nolookup_node) (vlib_main_t * vm,
3840 vlib_node_runtime_t * node,
3841 vlib_frame_t * from_frame)
3843 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3844 1 /* is_nolookup */ );
3848 VLIB_REGISTER_NODE (tcp4_input_nolookup_node) =
3850 .name = "tcp4-input-nolookup",
3851 /* Takes a vector of packets. */
3852 .vector_size = sizeof (u32),
3853 .n_errors = TCP_N_ERROR,
3854 .error_strings = tcp_error_strings,
3855 .n_next_nodes = TCP_INPUT_N_NEXT,
3858 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3859 foreach_tcp4_input_next
3862 .format_buffer = format_tcp_header,
3863 .format_trace = format_tcp_rx_trace,
3868 VLIB_REGISTER_NODE (tcp6_input_nolookup_node) =
3870 .name = "tcp6-input-nolookup",
3871 /* Takes a vector of packets. */
3872 .vector_size = sizeof (u32),
3873 .n_errors = TCP_N_ERROR,
3874 .error_strings = tcp_error_strings,
3875 .n_next_nodes = TCP_INPUT_N_NEXT,
3878 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3879 foreach_tcp6_input_next
3882 .format_buffer = format_tcp_header,
3883 .format_trace = format_tcp_rx_trace,
3887 VLIB_NODE_FN (tcp4_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3888 vlib_frame_t * from_frame)
3890 return tcp46_input_inline (vm, node, from_frame, 1 /* is_ip4 */ ,
3891 0 /* is_nolookup */ );
3894 VLIB_NODE_FN (tcp6_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
3895 vlib_frame_t * from_frame)
3897 return tcp46_input_inline (vm, node, from_frame, 0 /* is_ip4 */ ,
3898 0 /* is_nolookup */ );
3902 VLIB_REGISTER_NODE (tcp4_input_node) =
3904 .name = "tcp4-input",
3905 /* Takes a vector of packets. */
3906 .vector_size = sizeof (u32),
3907 .n_errors = TCP_N_ERROR,
3908 .error_strings = tcp_error_strings,
3909 .n_next_nodes = TCP_INPUT_N_NEXT,
3912 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3913 foreach_tcp4_input_next
3916 .format_buffer = format_tcp_header,
3917 .format_trace = format_tcp_rx_trace,
3922 VLIB_REGISTER_NODE (tcp6_input_node) =
3924 .name = "tcp6-input",
3925 /* Takes a vector of packets. */
3926 .vector_size = sizeof (u32),
3927 .n_errors = TCP_N_ERROR,
3928 .error_strings = tcp_error_strings,
3929 .n_next_nodes = TCP_INPUT_N_NEXT,
3932 #define _(s,n) [TCP_INPUT_NEXT_##s] = n,
3933 foreach_tcp6_input_next
3936 .format_buffer = format_tcp_header,
3937 .format_trace = format_tcp_rx_trace,
3941 #ifndef CLIB_MARCH_VARIANT
3943 tcp_dispatch_table_init (tcp_main_t * tm)
3946 for (i = 0; i < ARRAY_LEN (tm->dispatch_table); i++)
3947 for (j = 0; j < ARRAY_LEN (tm->dispatch_table[i]); j++)
3949 tm->dispatch_table[i][j].next = TCP_INPUT_NEXT_DROP;
3950 tm->dispatch_table[i][j].error = TCP_ERROR_DISPATCH;
3953 #define _(t,f,n,e) \
3955 tm->dispatch_table[TCP_STATE_##t][f].next = (n); \
3956 tm->dispatch_table[TCP_STATE_##t][f].error = (e); \
3959 /* RFC 793: In LISTEN if RST drop and if ACK return RST */
3960 _(LISTEN, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3961 _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_ACK_INVALID);
3962 _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_INVALID_CONNECTION);
3963 _(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
3964 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3965 TCP_ERROR_ACK_INVALID);
3966 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3967 TCP_ERROR_SEGMENT_INVALID);
3968 _(LISTEN, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3969 TCP_ERROR_SEGMENT_INVALID);
3970 _(LISTEN, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3971 TCP_ERROR_INVALID_CONNECTION);
3972 _(LISTEN, TCP_FLAG_FIN, TCP_INPUT_NEXT_RESET, TCP_ERROR_SEGMENT_INVALID);
3973 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
3974 TCP_ERROR_SEGMENT_INVALID);
3975 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3976 TCP_ERROR_SEGMENT_INVALID);
3977 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3978 TCP_ERROR_SEGMENT_INVALID);
3979 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_DROP,
3980 TCP_ERROR_SEGMENT_INVALID);
3981 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
3982 TCP_ERROR_SEGMENT_INVALID);
3983 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_DROP,
3984 TCP_ERROR_SEGMENT_INVALID);
3985 _(LISTEN, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3986 TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
3987 /* ACK for for a SYN-ACK -> tcp-rcv-process. */
3988 _(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3989 _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3990 _(SYN_RCVD, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3992 _(SYN_RCVD, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3993 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
3995 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
3997 _(SYN_RCVD, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
3998 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
3999 _(SYN_RCVD, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4000 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4002 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4004 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4005 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4006 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4008 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4009 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4010 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4011 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4012 _(SYN_RCVD, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4013 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4014 _(SYN_RCVD, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4015 /* SYN-ACK for a SYN */
4016 _(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
4018 _(SYN_SENT, TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
4019 _(SYN_SENT, TCP_FLAG_RST, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
4020 _(SYN_SENT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
4022 _(SYN_SENT, TCP_FLAG_FIN, TCP_INPUT_NEXT_SYN_SENT, TCP_ERROR_NONE);
4023 _(SYN_SENT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
4025 /* ACK for for established connection -> tcp-established. */
4026 _(ESTABLISHED, TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4027 /* FIN for for established connection -> tcp-established. */
4028 _(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4029 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
4031 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
4033 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4034 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4035 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED,
4037 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4038 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4039 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4040 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4041 _(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4042 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4043 _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4044 _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
4046 _(ESTABLISHED, TCP_FLAG_SYN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4047 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
4049 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED,
4051 _(ESTABLISHED, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4052 TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
4053 _(ESTABLISHED, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4054 /* ACK or FIN-ACK to our FIN */
4055 _(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4056 _(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
4058 /* FIN in reply to our FIN from the other side */
4059 _(FIN_WAIT_1, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4060 _(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4061 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4063 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4064 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4065 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4066 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4067 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4068 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4069 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4071 _(FIN_WAIT_1, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4072 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4073 _(FIN_WAIT_1, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4074 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4076 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4078 _(FIN_WAIT_1, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4079 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4080 _(FIN_WAIT_1, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4081 _(FIN_WAIT_1, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4083 _(CLOSING, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4084 _(CLOSING, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4085 _(CLOSING, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4086 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4088 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4090 _(CLOSING, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4091 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4092 _(CLOSING, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4093 _(CLOSING, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4095 _(CLOSING, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4096 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4098 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4100 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4101 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4102 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4104 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4105 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4106 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4107 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4108 _(CLOSING, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4109 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4110 /* FIN confirming that the peer (app) has closed */
4111 _(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4112 _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4113 _(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4115 _(FIN_WAIT_2, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4116 _(FIN_WAIT_2, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4118 _(CLOSE_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4119 _(CLOSE_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4121 _(CLOSE_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4122 _(CLOSE_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4124 _(LAST_ACK, 0, TCP_INPUT_NEXT_DROP, TCP_ERROR_SEGMENT_INVALID);
4125 _(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4126 _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4127 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4129 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS,
4131 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_ACK,
4132 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4133 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4135 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_ACK,
4136 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4137 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST,
4138 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4139 _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4140 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4141 _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4142 _(LAST_ACK, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4144 _(LAST_ACK, TCP_FLAG_SYN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4145 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4147 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS,
4149 _(LAST_ACK, TCP_FLAG_SYN | TCP_FLAG_RST | TCP_FLAG_ACK,
4150 TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4151 _(TIME_WAIT, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
4152 _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4153 _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4155 _(TIME_WAIT, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4156 _(TIME_WAIT, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
4158 _(TIME_WAIT, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
4159 /* RFC793 CLOSED: An incoming segment containing a RST is discarded. An
4160 * incoming segment not containing a RST causes a RST to be sent in
4162 _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
4163 _(CLOSED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_DROP,
4164 TCP_ERROR_CONNECTION_CLOSED);
4165 _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
4166 _(CLOSED, TCP_FLAG_SYN, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
4167 _(CLOSED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET,
4168 TCP_ERROR_CONNECTION_CLOSED);
4172 static clib_error_t *
4173 tcp_input_init (vlib_main_t * vm)
4175 clib_error_t *error = 0;
4176 tcp_main_t *tm = vnet_get_tcp_main ();
4178 if ((error = vlib_call_init_function (vm, tcp_init)))
4181 /* Initialize dispatch table. */
4182 tcp_dispatch_table_init (tm);
4187 VLIB_INIT_FUNCTION (tcp_input_init);
4189 #endif /* CLIB_MARCH_VARIANT */
4192 * fd.io coding-style-patch-verification: ON
4195 * eval: (c-set-style "gnu")