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 <vnet/tcp/tcp.h>
17 #include <vnet/tcp/tcp_inlines.h>
20 typedef enum _tcp_output_next
23 TCP_OUTPUT_NEXT_IP_LOOKUP,
24 TCP_OUTPUT_NEXT_IP_REWRITE,
25 TCP_OUTPUT_NEXT_IP_ARP,
29 #define foreach_tcp4_output_next \
30 _ (DROP, "error-drop") \
31 _ (IP_LOOKUP, "ip4-lookup") \
32 _ (IP_REWRITE, "ip4-rewrite") \
35 #define foreach_tcp6_output_next \
36 _ (DROP, "error-drop") \
37 _ (IP_LOOKUP, "ip6-lookup") \
38 _ (IP_REWRITE, "ip6-rewrite") \
39 _ (IP_ARP, "ip6-discover-neighbor")
41 static char *tcp_error_strings[] = {
42 #define tcp_error(n,s) s,
43 #include <vnet/tcp/tcp_error.def>
49 tcp_header_t tcp_header;
50 tcp_connection_t tcp_connection;
54 format_tcp_tx_trace (u8 * s, va_list * args)
56 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
57 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
58 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
59 tcp_connection_t *tc = &t->tcp_connection;
60 u32 indent = format_get_indent (s);
62 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
63 format_tcp_state, tc->state, format_white_space, indent,
64 format_tcp_header, &t->tcp_header, 128);
69 #ifndef CLIB_MARCH_VARIANT
71 tcp_window_compute_scale (u32 window)
74 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
80 * TCP's initial window
83 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
85 /* RFC 6928 recommends the value lower. However at the time our connections
86 * are initialized, fifos may not be allocated. Therefore, advertise the
87 * smallest possible unscaled window size and update once fifos are
88 * assigned to the session.
91 tcp_update_rcv_mss (tc);
92 TCP_IW_N_SEGMENTS * tc->mss;
94 return tcp_cfg.min_rx_fifo;
98 * Compute initial window and scale factor. As per RFC1323, window field in
99 * SYN and SYN-ACK segments is never scaled.
102 tcp_initial_window_to_advertise (tcp_connection_t * tc)
104 /* Compute rcv wscale only if peer advertised support for it */
105 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
106 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
108 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
110 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
114 tcp_update_rcv_wnd (tcp_connection_t * tc)
116 u32 available_space, wnd;
120 * Figure out how much space we have available
122 available_space = transport_max_rx_enqueue (&tc->connection);
123 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
130 * Use the above and what we know about what we've previously advertised
131 * to compute the new window
133 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
135 /* Bad. Thou shalt not shrink */
136 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
138 wnd = clib_max (observed_wnd, 0);
139 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
143 wnd = available_space;
146 /* Make sure we have a multiple of rcv_wscale */
147 if (wnd && tc->rcv_wscale)
149 wnd &= ~((1 << tc->rcv_wscale) - 1);
151 wnd = 1 << tc->rcv_wscale;
154 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
158 * Compute and return window to advertise, scaled as per RFC1323
161 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
163 if (state < TCP_STATE_ESTABLISHED)
164 return tcp_initial_window_to_advertise (tc);
166 tcp_update_rcv_wnd (tc);
167 return tc->rcv_wnd >> tc->rcv_wscale;
171 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
175 opts->flags |= TCP_OPTS_FLAG_MSS;
177 len += TCP_OPTION_LEN_MSS;
179 opts->flags |= TCP_OPTS_FLAG_WSCALE;
180 opts->wscale = tc->rcv_wscale;
181 len += TCP_OPTION_LEN_WINDOW_SCALE;
183 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
184 opts->tsval = tcp_time_now ();
186 len += TCP_OPTION_LEN_TIMESTAMP;
190 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
191 len += TCP_OPTION_LEN_SACK_PERMITTED;
194 /* Align to needed boundary */
195 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
200 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
204 opts->flags |= TCP_OPTS_FLAG_MSS;
206 len += TCP_OPTION_LEN_MSS;
208 if (tcp_opts_wscale (&tc->rcv_opts))
210 opts->flags |= TCP_OPTS_FLAG_WSCALE;
211 opts->wscale = tc->rcv_wscale;
212 len += TCP_OPTION_LEN_WINDOW_SCALE;
215 if (tcp_opts_tstamp (&tc->rcv_opts))
217 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
218 opts->tsval = tcp_time_now ();
219 opts->tsecr = tc->tsval_recent;
220 len += TCP_OPTION_LEN_TIMESTAMP;
223 if (tcp_opts_sack_permitted (&tc->rcv_opts))
225 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
226 len += TCP_OPTION_LEN_SACK_PERMITTED;
229 /* Align to needed boundary */
230 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
235 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
241 if (tcp_opts_tstamp (&tc->rcv_opts))
243 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
244 opts->tsval = tcp_tstamp (tc);
245 opts->tsecr = tc->tsval_recent;
246 len += TCP_OPTION_LEN_TIMESTAMP;
248 if (tcp_opts_sack_permitted (&tc->rcv_opts))
250 if (vec_len (tc->snd_sacks))
252 opts->flags |= TCP_OPTS_FLAG_SACK;
253 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
254 tc->snd_sack_pos = 0;
255 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
256 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
257 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
258 TCP_OPTS_MAX_SACK_BLOCKS);
259 tc->snd_sack_pos += opts->n_sack_blocks;
260 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
264 /* Align to needed boundary */
265 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
270 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
275 case TCP_STATE_ESTABLISHED:
276 case TCP_STATE_CLOSE_WAIT:
277 case TCP_STATE_FIN_WAIT_1:
278 case TCP_STATE_LAST_ACK:
279 case TCP_STATE_CLOSING:
280 case TCP_STATE_FIN_WAIT_2:
281 case TCP_STATE_TIME_WAIT:
282 case TCP_STATE_CLOSED:
283 return tcp_make_established_options (tc, opts);
284 case TCP_STATE_SYN_RCVD:
285 return tcp_make_synack_options (tc, opts);
286 case TCP_STATE_SYN_SENT:
287 return tcp_make_syn_options (tc, opts);
289 clib_warning ("State not handled! %d", state);
295 * Update burst send vars
297 * - Updates snd_mss to reflect the effective segment size that we can send
298 * by taking into account all TCP options, including SACKs.
299 * - Cache 'on the wire' options for reuse
300 * - Updates receive window which can be reused for a burst.
302 * This should *only* be called when doing bursts
305 tcp_update_burst_snd_vars (tcp_connection_t * tc)
307 tcp_main_t *tm = &tcp_main;
309 /* Compute options to be used for connection. These may be reused when
310 * sending data or to compute the effective mss (snd_mss) */
311 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
312 TCP_STATE_ESTABLISHED);
314 /* XXX check if MTU has been updated */
315 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
316 ASSERT (tc->snd_mss > 0);
318 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
321 tcp_update_rcv_wnd (tc);
323 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
324 tcp_bt_check_app_limited (tc);
326 if (tc->snd_una == tc->snd_nxt)
328 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
329 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST);
333 #endif /* CLIB_MARCH_VARIANT */
336 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
338 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
339 vlib_buffer_free_one (vm, b->next_buffer);
340 /* Zero all flags but free list index and trace flag */
341 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
343 b->current_length = 0;
344 b->total_length_not_including_first_buffer = 0;
345 vnet_buffer (b)->tcp.flags = 0;
347 /* Leave enough space for headers */
348 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
351 #ifndef CLIB_MARCH_VARIANT
353 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
355 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
356 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
357 b->total_length_not_including_first_buffer = 0;
359 vnet_buffer (b)->tcp.flags = 0;
360 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
361 /* Leave enough space for headers */
362 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
366 /* Compute TCP checksum in software when offloading is disabled for a connection */
368 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
369 ip46_address_t * src, ip46_address_t * dst)
372 u16 payload_length_host_byte_order;
375 /* Initialize checksum with ip header. */
376 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
377 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
378 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
380 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
382 sum0 = ip_csum_with_carry
383 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
384 sum0 = ip_csum_with_carry
385 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
388 return ip_calculate_l4_checksum (vm, p0, sum0,
389 payload_length_host_byte_order, NULL, 0,
394 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
395 ip46_address_t * src, ip46_address_t * dst)
398 u32 payload_length_host_byte_order;
400 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
402 clib_host_to_net_u32 (payload_length_host_byte_order +
403 (IP_PROTOCOL_TCP << 16));
405 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
406 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
408 return ip_calculate_l4_checksum (vm, p0, sum0,
409 payload_length_host_byte_order, NULL, 0,
414 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
417 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
419 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
420 vlib_main_t *vm = wrk->vm;
423 checksum = ip4_tcp_compute_checksum_custom
424 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
426 checksum = ip6_tcp_compute_checksum_custom
427 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
431 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
440 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
443 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
444 u8 tcp_opts_len, tcp_hdr_opts_len;
448 wnd = tcp_window_to_advertise (tc, state);
450 /* Make and write options */
451 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
452 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
454 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
455 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
457 tcp_options_write ((u8 *) (th + 1), snd_opts);
459 th->checksum = tcp_compute_checksum (tc, b);
461 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
464 tcp_zero_rwnd_sent_on (tc);
466 tcp_zero_rwnd_sent_off (tc);
470 * Convert buffer to ACK
473 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
475 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
476 TCP_EVT (TCP_EVT_ACK_SENT, tc);
477 tc->rcv_las = tc->rcv_nxt;
481 * Convert buffer to FIN-ACK
484 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
486 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
490 * Convert buffer to SYN
493 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
495 u8 tcp_hdr_opts_len, tcp_opts_len;
498 tcp_options_t snd_opts;
500 initial_wnd = tcp_initial_window_to_advertise (tc);
502 /* Make and write options */
503 clib_memset (&snd_opts, 0, sizeof (snd_opts));
504 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
505 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
507 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
508 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
510 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
511 tcp_options_write ((u8 *) (th + 1), &snd_opts);
512 th->checksum = tcp_compute_checksum (tc, b);
516 * Convert buffer to SYN-ACK
519 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
521 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
522 u8 tcp_opts_len, tcp_hdr_opts_len;
526 clib_memset (snd_opts, 0, sizeof (*snd_opts));
527 initial_wnd = tcp_initial_window_to_advertise (tc);
528 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
529 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
531 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
532 tc->rcv_nxt, tcp_hdr_opts_len,
533 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
534 tcp_options_write ((u8 *) (th + 1), snd_opts);
536 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
537 th->checksum = tcp_compute_checksum (tc, b);
541 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
542 u8 is_ip4, u32 fib_index)
544 tcp_main_t *tm = &tcp_main;
545 vlib_main_t *vm = wrk->vm;
547 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
550 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
551 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
553 tcp_trajectory_add_start (b, 1);
555 session_add_pending_tx_buffer (vm->thread_index, bi,
556 tm->ipl_next_node[!is_ip4]);
558 if (vm->thread_index == 0 && vlib_num_workers ())
559 session_queue_run_on_main_thread (wrk->vm);
563 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
566 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
569 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
570 wrk->tco_next_node[!is_ip4]);
573 #endif /* CLIB_MARCH_VARIANT */
576 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b, u8 is_ip4)
581 ip4_address_t src_ip4, dst_ip4;
582 ip6_address_t src_ip6, dst_ip6;
583 u16 src_port, dst_port;
584 u32 tmp, len, seq, ack;
587 /* Find IP and TCP headers */
588 th = tcp_buffer_hdr (b);
590 /* Save src and dst ip */
593 ih4 = vlib_buffer_get_current (b);
594 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
595 src_ip4.as_u32 = ih4->src_address.as_u32;
596 dst_ip4.as_u32 = ih4->dst_address.as_u32;
600 ih6 = vlib_buffer_get_current (b);
601 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
602 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
603 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
606 src_port = th->src_port;
607 dst_port = th->dst_port;
608 flags = TCP_FLAG_RST;
611 * RFC 793. If the ACK bit is off, sequence number zero is used,
612 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
613 * If the ACK bit is on,
614 * <SEQ=SEG.ACK><CTL=RST>
618 seq = th->ack_number;
623 flags |= TCP_FLAG_ACK;
624 tmp = clib_net_to_host_u32 (th->seq_number);
625 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
626 ack = clib_host_to_net_u32 (tmp + len);
630 tcp_reuse_buffer (vm, b);
631 tcp_trajectory_add_start (b, 4);
632 th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack,
633 sizeof (tcp_header_t), flags, 0);
637 ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4,
639 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
644 ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP);
645 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
652 #ifndef CLIB_MARCH_VARIANT
654 * Send reset without reusing existing buffer
656 * It extracts connection info out of original packet
659 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
660 u32 thread_index, u8 is_ip4)
662 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
663 vlib_main_t *vm = wrk->vm;
665 u32 bi, sw_if_index, fib_index;
666 u8 tcp_hdr_len, flags = 0;
667 tcp_header_t *th, *pkt_th;
669 ip4_header_t *ih4, *pkt_ih4;
670 ip6_header_t *ih6, *pkt_ih6;
671 fib_protocol_t fib_proto;
673 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
676 b = vlib_get_buffer (vm, bi);
677 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
678 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
679 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
680 tcp_init_buffer (vm, b);
682 /* Make and write options */
683 tcp_hdr_len = sizeof (tcp_header_t);
687 pkt_ih4 = vlib_buffer_get_current (pkt);
688 pkt_th = ip4_next_header (pkt_ih4);
692 pkt_ih6 = vlib_buffer_get_current (pkt);
693 pkt_th = ip6_next_header (pkt_ih6);
696 if (tcp_ack (pkt_th))
698 flags = TCP_FLAG_RST;
699 seq = pkt_th->ack_number;
700 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
704 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
706 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
709 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
710 seq, ack, tcp_hdr_len, flags, 0);
712 /* Swap src and dst ip */
715 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
716 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
717 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
718 tcp_csum_offload (tc));
719 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
724 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
726 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
727 &pkt_ih6->src_address,
729 tc->ipv6_flow_label);
730 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
734 tcp_enqueue_to_ip_lookup (wrk, b, bi, is_ip4, fib_index);
735 TCP_EVT (TCP_EVT_RST_SENT, tc);
736 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
737 TCP_ERROR_RST_SENT, 1);
741 * Build and set reset packet for connection
744 tcp_send_reset (tcp_connection_t * tc)
746 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
747 vlib_main_t *vm = wrk->vm;
751 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
754 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
756 b = vlib_get_buffer (vm, bi);
757 tcp_init_buffer (vm, b);
759 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
760 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
761 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
762 flags = TCP_FLAG_RST;
763 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
764 tc->rcv_nxt, tcp_hdr_opts_len, flags,
766 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
767 th->checksum = tcp_compute_checksum (tc, b);
768 ASSERT (opts_write_len == tc->snd_opts_len);
769 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
770 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
771 TCP_EVT (TCP_EVT_RST_SENT, tc);
772 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
773 TCP_ERROR_RST_SENT, 1);
777 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
782 vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4,
783 IP_PROTOCOL_TCP, tcp_csum_offload (tc));
787 vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6,
788 IP_PROTOCOL_TCP, tc->ipv6_flow_label);
795 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
796 * The packet is not forwarded through tcpx_output to avoid doing lookups
797 * in the half_open pool.
800 tcp_send_syn (tcp_connection_t * tc)
802 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
803 vlib_main_t *vm = wrk->vm;
808 * Setup retransmit and establish timers before requesting buffer
809 * such that we can return if we've ran out.
811 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
812 tc->rto * TCP_TO_TIMER_TICK);
814 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
816 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
820 b = vlib_get_buffer (vm, bi);
821 tcp_init_buffer (vm, b);
822 tcp_make_syn (tc, b);
824 /* Measure RTT with this */
825 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
826 tc->rtt_seq = tc->snd_nxt;
829 tcp_push_ip_hdr (wrk, tc, b);
830 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
831 TCP_EVT (TCP_EVT_SYN_SENT, tc);
835 tcp_send_synack (tcp_connection_t * tc)
837 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
838 vlib_main_t *vm = wrk->vm;
842 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
844 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
846 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
850 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
851 b = vlib_get_buffer (vm, bi);
852 tcp_init_buffer (vm, b);
853 tcp_make_synack (tc, b);
854 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
855 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
862 tcp_send_fin (tcp_connection_t * tc)
864 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
865 vlib_main_t *vm = wrk->vm;
870 fin_snt = tc->flags & TCP_CONN_FINSNT;
874 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
876 /* Out of buffers so program fin retransmit ASAP */
877 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
881 /* Make sure retransmit retries a fin not data */
882 tc->flags |= TCP_CONN_FINSNT;
886 /* If we have non-dupacks programmed, no need to send them */
887 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
888 tc->flags &= ~TCP_CONN_SNDACK;
890 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
891 b = vlib_get_buffer (vm, bi);
892 tcp_init_buffer (vm, b);
893 tcp_make_fin (tc, b);
894 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
895 TCP_EVT (TCP_EVT_FIN_SENT, tc);
896 /* Account for the FIN */
900 tc->flags |= TCP_CONN_FINSNT;
901 tc->flags &= ~TCP_CONN_FINPNDG;
902 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
907 * Push TCP header and update connection variables. Should only be called
908 * for segments with data, not for 'control' packets.
911 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
912 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
914 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
915 u32 advertise_wnd, data_len;
916 tcp_main_t *tm = &tcp_main;
919 data_len = b->current_length;
920 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
921 data_len += b->total_length_not_including_first_buffer;
923 vnet_buffer (b)->tcp.flags = 0;
924 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
927 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
929 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
932 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
934 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
936 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
938 if (seq_geq (tc->psh_seq, snd_nxt)
939 && seq_lt (tc->psh_seq, snd_nxt + data_len))
940 flags |= TCP_FLAG_PSH;
942 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
943 tc->rcv_nxt, tcp_hdr_opts_len, flags,
948 clib_memcpy_fast ((u8 *) (th + 1),
949 tm->wrk_ctx[tc->c_thread_index].cached_opts,
954 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
955 ASSERT (len == tc->snd_opts_len);
959 * Update connection variables
963 tc->snd_nxt += data_len;
964 tc->rcv_las = tc->rcv_nxt;
966 tc->bytes_out += data_len;
967 tc->data_segs_out += 1;
969 th->checksum = tcp_compute_checksum (tc, b);
971 TCP_EVT (TCP_EVT_PKTIZE, tc);
975 tcp_buffer_len (vlib_buffer_t * b)
977 u32 data_len = b->current_length;
978 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
979 data_len += b->total_length_not_including_first_buffer;
984 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
986 tcp_connection_t *tc = (tcp_connection_t *) tconn;
988 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
989 tcp_bt_track_tx (tc, tcp_buffer_len (b));
991 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
992 /* update_snd_nxt */ 1);
994 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
995 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
996 /* If not tracking an ACK, start tracking */
997 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
999 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1000 tc->rtt_seq = tc->snd_nxt;
1002 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1004 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1005 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
1008 tcp_trajectory_add_start (b, 3);
1013 tcp_send_ack (tcp_connection_t * tc)
1015 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1016 vlib_main_t *vm = wrk->vm;
1020 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1022 tcp_update_rcv_wnd (tc);
1025 b = vlib_get_buffer (vm, bi);
1026 tcp_init_buffer (vm, b);
1027 tcp_make_ack (tc, b);
1028 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1032 tcp_program_ack (tcp_connection_t * tc)
1034 if (!(tc->flags & TCP_CONN_SNDACK))
1036 session_add_self_custom_tx_evt (&tc->connection, 1);
1037 tc->flags |= TCP_CONN_SNDACK;
1042 tcp_program_dupack (tcp_connection_t * tc)
1044 if (!(tc->flags & TCP_CONN_SNDACK))
1046 session_add_self_custom_tx_evt (&tc->connection, 1);
1047 tc->flags |= TCP_CONN_SNDACK;
1049 if (tc->pending_dupacks < 255)
1050 tc->pending_dupacks += 1;
1054 tcp_program_retransmit (tcp_connection_t * tc)
1056 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1058 session_add_self_custom_tx_evt (&tc->connection, 0);
1059 tc->flags |= TCP_CONN_RXT_PENDING;
1064 * Delayed ack timer handler
1066 * Sends delayed ACK when timer expires
1069 tcp_timer_delack_handler (tcp_connection_t * tc)
1075 * Send window update ack
1077 * Ensures that it will be sent only once, after a zero rwnd has been
1078 * advertised in a previous ack, and only if rwnd has grown beyond a
1079 * configurable value.
1082 tcp_send_window_update_ack (tcp_connection_t * tc)
1084 if (tcp_zero_rwnd_sent (tc))
1086 tcp_update_rcv_wnd (tc);
1087 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1089 tcp_zero_rwnd_sent_off (tc);
1090 tcp_program_ack (tc);
1096 * Allocate a new buffer and build a new tcp segment
1098 * @param wrk tcp worker
1099 * @param tc connection for which the segment will be allocated
1100 * @param offset offset of the first byte in the tx fifo
1101 * @param max_deq_byte segment size
1102 * @param[out] b pointer to buffer allocated
1104 * @return the number of bytes in the segment or 0 if buffer cannot be
1105 * allocated or no data available
1108 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1109 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1111 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1112 vlib_main_t *vm = wrk->vm;
1117 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1122 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1125 * Allocate and fill in buffer(s)
1128 /* Easy case, buffer size greater than mss */
1129 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1131 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1133 *b = vlib_get_buffer (vm, bi);
1134 data = tcp_init_buffer (vm, *b);
1135 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1137 ASSERT (n_bytes == max_deq_bytes);
1138 b[0]->current_length = n_bytes;
1139 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1140 /* burst */ 0, /* update_snd_nxt */ 0);
1142 /* Split mss into multiple buffers */
1145 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1146 u16 n_peeked, len_to_deq;
1147 vlib_buffer_t *chain_b, *prev_b;
1150 /* Make sure we have enough buffers */
1151 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1152 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1153 CLIB_CACHE_LINE_BYTES);
1154 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1155 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1158 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1162 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1163 data = tcp_init_buffer (vm, *b);
1164 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1166 TRANSPORT_MAX_HDRS_LEN);
1167 b[0]->current_length = n_bytes;
1168 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1169 b[0]->total_length_not_including_first_buffer = 0;
1170 max_deq_bytes -= n_bytes;
1173 for (i = 1; i < n_bufs_per_seg; i++)
1176 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1177 chain_bi = wrk->tx_buffers[--n_bufs];
1178 chain_b = vlib_get_buffer (vm, chain_bi);
1179 chain_b->current_data = 0;
1180 data = vlib_buffer_get_current (chain_b);
1181 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1184 ASSERT (n_peeked == len_to_deq);
1185 n_bytes += n_peeked;
1186 chain_b->current_length = n_peeked;
1187 chain_b->next_buffer = 0;
1189 /* update previous buffer */
1190 prev_b->next_buffer = chain_bi;
1191 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1193 max_deq_bytes -= n_peeked;
1194 b[0]->total_length_not_including_first_buffer += n_peeked;
1197 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1198 /* burst */ 0, /* update_snd_nxt */ 0);
1200 if (PREDICT_FALSE (n_bufs))
1202 clib_warning ("not all buffers consumed");
1203 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1207 ASSERT (n_bytes > 0);
1208 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1214 * Build a retransmit segment
1216 * @return the number of bytes in the segment or 0 if there's nothing to
1220 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1221 tcp_connection_t * tc, u32 offset,
1222 u32 max_deq_bytes, vlib_buffer_t ** b)
1224 u32 start, available_bytes;
1227 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1228 ASSERT (max_deq_bytes != 0);
1231 * Make sure we can retransmit something
1233 available_bytes = transport_max_tx_dequeue (&tc->connection);
1234 ASSERT (available_bytes >= offset);
1235 available_bytes -= offset;
1236 if (!available_bytes)
1239 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1240 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1242 start = tc->snd_una + offset;
1243 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1245 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1249 tc->snd_rxt_bytes += n_bytes;
1251 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1252 tcp_bt_track_rxt (tc, start, start + n_bytes);
1254 tc->bytes_retrans += n_bytes;
1255 tc->segs_retrans += 1;
1256 tcp_worker_stats_inc (wrk, rxt_segs, 1);
1257 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1263 tcp_check_sack_reneging (tcp_connection_t * tc)
1265 sack_scoreboard_t *sb = &tc->sack_sb;
1266 sack_scoreboard_hole_t *hole;
1268 hole = scoreboard_first_hole (sb);
1269 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1272 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1276 * Reset congestion control, switch cwnd to loss window and try again.
1279 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1281 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1283 tc->prev_ssthresh = tc->ssthresh;
1284 tc->prev_cwnd = tc->cwnd;
1286 /* If we entrered loss without fast recovery, notify cc algo of the
1287 * congestion event such that it can update ssthresh and its state */
1288 if (!tcp_in_fastrecovery (tc))
1289 tcp_cc_congestion (tc);
1291 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1295 tc->cwnd_acc_bytes = 0;
1296 tc->tr_occurences += 1;
1297 tcp_recovery_on (tc);
1301 tcp_timer_retransmit_handler (tcp_connection_t * tc)
1303 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1304 vlib_main_t *vm = wrk->vm;
1305 vlib_buffer_t *b = 0;
1308 tcp_worker_stats_inc (wrk, tr_events, 1);
1310 /* Should be handled by a different handler */
1311 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
1314 /* Wait-close and retransmit could pop at the same time */
1315 if (tc->state == TCP_STATE_CLOSED)
1318 if (tc->state >= TCP_STATE_ESTABLISHED)
1320 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1322 /* Lost FIN, retransmit and return */
1323 if (tc->flags & TCP_CONN_FINSNT)
1327 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1331 /* Shouldn't be here. This condition is tricky because it has to take
1332 * into account boff > 0 due to persist timeout. */
1333 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1334 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1335 && !tcp_flight_size (tc)))
1337 ASSERT (!tcp_in_recovery (tc));
1342 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1343 * to persist timer timeout */
1344 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1347 tcp_update_rto (tc);
1350 /* Peer is dead or network connectivity is lost. Close connection.
1351 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1352 * a min rto of 0.2s we need to retry about 8 times. */
1353 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1355 tcp_send_reset (tc);
1356 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1357 session_transport_closing_notify (&tc->connection);
1358 session_transport_closed_notify (&tc->connection);
1359 tcp_connection_timers_reset (tc);
1360 tcp_program_cleanup (wrk, tc);
1361 tcp_worker_stats_inc (wrk, tr_abort, 1);
1365 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1366 tcp_check_sack_reneging (tc);
1368 /* Update send congestion to make sure that rxt has data to send */
1369 tc->snd_congestion = tc->snd_nxt;
1371 /* Send the first unacked segment. If we're short on buffers, return
1372 * as soon as possible */
1373 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1374 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1377 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1381 bi = vlib_get_buffer_index (vm, b);
1382 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1384 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1385 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
1388 if (tc->rto_boff == 1)
1390 tcp_cc_init_rxt_timeout (tc);
1391 /* Record timestamp. Eifel detection algorithm RFC3522 */
1392 tc->snd_rxt_ts = tcp_tstamp (tc);
1395 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1396 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1398 tcp_program_retransmit (tc);
1400 /* Retransmit SYN-ACK */
1401 else if (tc->state == TCP_STATE_SYN_RCVD)
1403 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1407 /* Passive open establish timeout */
1408 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1410 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1411 tcp_connection_timers_reset (tc);
1412 tcp_program_cleanup (wrk, tc);
1413 tcp_worker_stats_inc (wrk, tr_abort, 1);
1417 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1419 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1424 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1425 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1427 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
1429 b = vlib_get_buffer (vm, bi);
1430 tcp_init_buffer (vm, b);
1431 tcp_make_synack (tc, b);
1432 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1434 /* Retransmit timer already updated, just enqueue to output */
1435 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1439 ASSERT (tc->state == TCP_STATE_CLOSED);
1445 * SYN retransmit timer handler. Active open only.
1448 tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
1450 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1451 vlib_main_t *vm = wrk->vm;
1452 vlib_buffer_t *b = 0;
1455 /* Note: the connection may have transitioned to ESTABLISHED... */
1456 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
1459 /* Half-open connection actually moved to established but we were
1460 * waiting for syn retransmit to pop to call cleanup from the right
1462 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1464 if (tcp_half_open_connection_cleanup (tc))
1465 TCP_DBG ("could not remove half-open connection");
1469 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1472 /* Active open establish timeout */
1473 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1475 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
1476 tcp_connection_cleanup (tc);
1480 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1482 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1486 /* Try without increasing RTO a number of times. If this fails,
1487 * start growing RTO exponentially */
1489 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1490 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1492 b = vlib_get_buffer (vm, bi);
1493 tcp_init_buffer (vm, b);
1494 tcp_make_syn (tc, b);
1496 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1498 /* This goes straight to ipx_lookup */
1499 tcp_push_ip_hdr (wrk, tc, b);
1500 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1502 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1503 tc->rto * TCP_TO_TIMER_TICK);
1507 * Got 0 snd_wnd from peer, try to do something about it.
1511 tcp_timer_persist_handler (tcp_connection_t * tc)
1513 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1514 u32 bi, max_snd_bytes, available_bytes, offset;
1515 tcp_main_t *tm = vnet_get_tcp_main ();
1516 vlib_main_t *vm = wrk->vm;
1521 /* Problem already solved or worse */
1522 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1523 || (tc->flags & TCP_CONN_FINSNT))
1524 goto update_scheduler;
1526 available_bytes = transport_max_tx_dequeue (&tc->connection);
1527 offset = tc->snd_nxt - tc->snd_una;
1529 /* Reprogram persist if no new bytes available to send. We may have data
1531 if (!available_bytes)
1533 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1537 if (available_bytes <= offset)
1538 goto update_scheduler;
1540 /* Increment RTO backoff */
1542 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1545 * Try to force the first unsent segment (or buffer)
1547 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1549 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1553 b = vlib_get_buffer (vm, bi);
1554 data = tcp_init_buffer (vm, b);
1556 tcp_validate_txf_size (tc, offset);
1557 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1558 max_snd_bytes = clib_min (tc->snd_mss,
1559 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1560 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1562 b->current_length = n_bytes;
1563 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1564 || tc->snd_nxt == tc->snd_una_max
1565 || tc->rto_boff > 1));
1567 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1569 tcp_bt_check_app_limited (tc);
1570 tcp_bt_track_tx (tc, n_bytes);
1573 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1574 /* burst */ 0, /* update_snd_nxt */ 1);
1575 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1576 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1577 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1579 /* Just sent new data, enable retransmit */
1580 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1586 if (tcp_is_descheduled (tc))
1587 transport_connection_reschedule (&tc->connection);
1591 * Retransmit first unacked segment
1594 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1596 vlib_main_t *vm = wrk->vm;
1600 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1602 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1606 bi = vlib_get_buffer_index (vm, b);
1607 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1613 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1616 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1617 vlib_main_t *vm = wrk->vm;
1618 vlib_buffer_t *b = 0;
1620 offset = tc->snd_nxt - tc->snd_una;
1621 available_wnd = tc->snd_wnd - offset;
1622 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1624 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1625 tcp_bt_check_app_limited (tc);
1627 while (n_segs < burst_size)
1629 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1633 bi = vlib_get_buffer_index (vm, b);
1634 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1635 offset += n_written;
1638 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1639 tcp_bt_track_tx (tc, n_written);
1641 tc->snd_nxt += n_written;
1642 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1650 * Estimate send space using proportional rate reduction (RFC6937)
1653 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1658 pipe = tcp_flight_size (tc);
1659 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1661 if (pipe > tc->ssthresh)
1663 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1669 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1670 space = clib_min (tc->ssthresh - pipe, limit);
1672 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1677 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1678 sack_scoreboard_t * sb)
1680 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1681 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1683 if (tcp_fastrecovery_first (tc))
1686 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1690 tcp_max_tx_deq (tcp_connection_t * tc)
1692 return (transport_max_tx_dequeue (&tc->connection)
1693 - (tc->snd_nxt - tc->snd_una));
1696 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1697 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1698 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1701 * Do retransmit with SACKs
1704 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1707 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1708 u8 snd_limited = 0, can_rescue = 0;
1709 u32 bi, max_deq, burst_bytes;
1710 sack_scoreboard_hole_t *hole;
1711 vlib_main_t *vm = wrk->vm;
1712 vlib_buffer_t *b = 0;
1713 sack_scoreboard_t *sb;
1716 ASSERT (tcp_in_cong_recovery (tc));
1718 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1719 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1722 tcp_program_retransmit (tc);
1726 if (tcp_in_recovery (tc))
1727 snd_space = tcp_available_cc_snd_space (tc);
1729 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1731 if (snd_space < tc->snd_mss)
1736 /* Check if snd_una is a lost retransmit */
1737 if (pool_elts (sb->holes)
1738 && seq_gt (sb->high_sacked, tc->snd_congestion)
1739 && tc->rxt_head != tc->snd_una
1740 && tcp_retransmit_should_retry_head (tc, sb))
1742 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1743 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1746 tcp_program_retransmit (tc);
1749 bi = vlib_get_buffer_index (vm, b);
1750 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1753 tc->rxt_head = tc->snd_una;
1754 tc->rxt_delivered += n_written;
1755 tc->prr_delivered += n_written;
1756 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1759 tcp_fastrecovery_first_off (tc);
1761 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1762 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1764 max_deq = transport_max_tx_dequeue (&tc->connection);
1765 max_deq -= tc->snd_nxt - tc->snd_una;
1767 while (snd_space > 0 && n_segs < burst_size)
1769 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1773 /* We are out of lost holes to retransmit so send some new data. */
1774 if (max_deq > tc->snd_mss)
1779 /* Make sure we don't exceed available window and leave space
1780 * for one more packet, to avoid zero window acks */
1781 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1782 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1783 snd_space = clib_min (snd_space, av_wnd);
1784 snd_space = clib_min (max_deq, snd_space);
1785 burst_size = clib_min (burst_size - n_segs,
1786 snd_space / tc->snd_mss);
1787 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1788 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1789 if (max_deq > n_segs_new * tc->snd_mss)
1790 tcp_program_retransmit (tc);
1792 n_segs += n_segs_new;
1796 if (tcp_in_recovery (tc) || !can_rescue
1797 || scoreboard_rescue_rxt_valid (sb, tc))
1800 /* If rescue rxt undefined or less than snd_una then one segment of
1801 * up to SMSS octets that MUST include the highest outstanding
1802 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1803 * RecoveryPoint. HighRxt MUST NOT be updated.
1805 hole = scoreboard_last_hole (sb);
1806 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1807 max_bytes = clib_min (max_bytes, snd_space);
1808 offset = hole->end - tc->snd_una - max_bytes;
1809 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1814 sb->rescue_rxt = tc->snd_congestion;
1815 bi = vlib_get_buffer_index (vm, b);
1816 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1821 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1822 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1826 offset = sb->high_rxt - tc->snd_una;
1827 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1829 ASSERT (n_written <= snd_space);
1831 /* Nothing left to retransmit */
1835 bi = vlib_get_buffer_index (vm, b);
1836 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1838 sb->high_rxt += n_written;
1839 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1841 snd_space -= n_written;
1846 tcp_program_retransmit (tc);
1850 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
1855 * Fast retransmit without SACK info
1858 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1861 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
1862 u32 burst_bytes, sent_bytes;
1863 vlib_main_t *vm = wrk->vm;
1864 int snd_space, n_segs = 0;
1868 ASSERT (tcp_in_cong_recovery (tc));
1869 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1871 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1872 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1875 tcp_program_retransmit (tc);
1879 snd_space = tcp_available_cc_snd_space (tc);
1880 cc_limited = snd_space < burst_bytes;
1882 if (!tcp_fastrecovery_first (tc))
1885 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1887 while (snd_space > 0 && n_segs < burst_size)
1889 max_bytes = clib_min (tc->snd_mss,
1890 tc->snd_congestion - tc->snd_una - offset);
1893 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1896 /* Nothing left to retransmit */
1900 bi = vlib_get_buffer_index (vm, b);
1901 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1902 snd_space -= n_written;
1903 offset += n_written;
1907 if (n_segs == burst_size)
1912 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1913 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1916 max_deq = transport_max_tx_dequeue (&tc->connection);
1917 max_deq -= tc->snd_nxt - tc->snd_una;
1920 snd_space = clib_min (max_deq, snd_space);
1921 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1922 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1923 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
1924 tcp_program_retransmit (tc);
1925 n_segs += n_segs_now;
1929 tcp_fastrecovery_first_off (tc);
1931 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1932 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1933 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1939 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1943 if (!tc->pending_dupacks)
1945 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1946 || tc->state != TCP_STATE_ESTABLISHED)
1954 /* If we're supposed to send dupacks but have no ooo data
1955 * send only one ack */
1956 if (!vec_len (tc->snd_sacks))
1959 tc->dupacks_out += 1;
1960 tc->pending_dupacks = 0;
1964 /* Start with first sack block */
1965 tc->snd_sack_pos = 0;
1967 /* Generate enough dupacks to cover all sack blocks. Do not generate
1968 * more sacks than the number of packets received. But do generate at
1969 * least 3, i.e., the number needed to signal congestion, if needed. */
1970 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1971 n_acks = clib_min (n_acks, tc->pending_dupacks);
1972 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1973 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1976 if (n_acks < max_burst_size)
1978 tc->pending_dupacks = 0;
1979 tc->snd_sack_pos = 0;
1980 tc->dupacks_out += n_acks;
1985 TCP_DBG ("constrained by burst size");
1986 tc->pending_dupacks = n_acks - max_burst_size;
1987 tc->dupacks_out += max_burst_size;
1988 tcp_program_dupack (tc);
1989 return max_burst_size;
1994 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
1996 tcp_worker_ctx_t *wrk;
1999 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2002 wrk = tcp_get_worker (tc->c_thread_index);
2004 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2005 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2007 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2013 tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
2015 tcp_connection_t *tc = (tcp_connection_t *) conn;
2018 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2020 tc->flags &= ~TCP_CONN_RXT_PENDING;
2021 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
2024 if (!(tc->flags & TCP_CONN_SNDACK))
2027 tc->flags &= ~TCP_CONN_SNDACK;
2029 /* We have retransmitted packets and no dupack */
2030 if (n_segs && !tc->pending_dupacks)
2033 if (sp->max_burst_size <= n_segs)
2035 tcp_program_ack (tc);
2039 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
2043 #endif /* CLIB_MARCH_VARIANT */
2046 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2047 u16 * next0, u32 * error0)
2049 ip_adjacency_t *adj;
2052 /* Not thread safe but as long as the connection exists the adj should
2054 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2056 if (ai == ADJ_INDEX_INVALID)
2058 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2059 *next0 = TCP_OUTPUT_NEXT_DROP;
2060 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2065 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2066 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2067 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2068 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2071 *next0 = TCP_OUTPUT_NEXT_DROP;
2072 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2074 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2078 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2079 u32 * to_next, u32 n_bufs)
2081 tcp_connection_t *tc;
2087 for (i = 0; i < n_bufs; i++)
2089 b = vlib_get_buffer (vm, to_next[i]);
2090 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2092 th = vlib_buffer_get_current (b);
2093 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2095 t = vlib_add_trace (vm, node, b, sizeof (*t));
2096 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2097 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2102 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2103 tcp_connection_t * tc0, u8 is_ip4)
2105 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2106 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2107 b0->current_length);
2110 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2111 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2113 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2114 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
2118 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2120 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2123 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2125 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2126 data_len += b->total_length_not_including_first_buffer;
2128 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2132 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2133 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2134 b->flags |= VNET_BUFFER_F_GSO;
2135 vnet_buffer2 (b)->gso_l4_hdr_sz =
2136 sizeof (tcp_header_t) + tc->snd_opts_len;
2137 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2142 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2143 vlib_node_runtime_t * error_node, u16 * next0,
2146 /* If next_index is not drop use it */
2147 if (tc0->next_node_index)
2149 *next0 = tc0->next_node_index;
2150 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2154 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2157 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2158 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2164 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2165 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2167 if (PREDICT_FALSE (error0))
2169 b0->error = error_node->errors[error0];
2178 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2179 vlib_frame_t * frame, int is_ip4)
2181 u32 n_left_from, *from, thread_index = vm->thread_index;
2182 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2183 u16 nexts[VLIB_FRAME_SIZE], *next;
2185 from = vlib_frame_vector_args (frame);
2186 n_left_from = frame->n_vectors;
2187 tcp_set_time_now (tcp_get_worker (thread_index));
2189 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2190 tcp46_output_trace_frame (vm, node, from, n_left_from);
2192 vlib_get_buffers (vm, from, bufs, n_left_from);
2196 while (n_left_from >= 4)
2198 tcp_connection_t *tc0, *tc1;
2201 vlib_prefetch_buffer_header (b[2], STORE);
2202 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2204 vlib_prefetch_buffer_header (b[3], STORE);
2205 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2208 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2210 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2213 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2215 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2216 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2218 tcp_check_if_gso (tc0, b[0]);
2219 tcp_check_if_gso (tc1, b[1]);
2221 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2222 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2228 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2229 tcp_check_if_gso (tc0, b[0]);
2230 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2234 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2235 next[0] = TCP_OUTPUT_NEXT_DROP;
2239 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2240 tcp_check_if_gso (tc1, b[1]);
2241 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2245 b[1]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2246 next[1] = TCP_OUTPUT_NEXT_DROP;
2254 while (n_left_from > 0)
2256 tcp_connection_t *tc0;
2258 if (n_left_from > 1)
2260 vlib_prefetch_buffer_header (b[1], STORE);
2261 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2264 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2267 if (PREDICT_TRUE (tc0 != 0))
2269 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2270 tcp_check_if_gso (tc0, b[0]);
2271 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2275 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2276 next[0] = TCP_OUTPUT_NEXT_DROP;
2284 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2285 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2286 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2287 return frame->n_vectors;
2290 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2291 vlib_frame_t * from_frame)
2293 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2296 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2297 vlib_frame_t * from_frame)
2299 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2303 VLIB_REGISTER_NODE (tcp4_output_node) =
2305 .name = "tcp4-output",
2306 /* Takes a vector of packets. */
2307 .vector_size = sizeof (u32),
2308 .n_errors = TCP_N_ERROR,
2309 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2310 .error_strings = tcp_error_strings,
2311 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2313 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2314 foreach_tcp4_output_next
2317 .format_buffer = format_tcp_header,
2318 .format_trace = format_tcp_tx_trace,
2323 VLIB_REGISTER_NODE (tcp6_output_node) =
2325 .name = "tcp6-output",
2326 /* Takes a vector of packets. */
2327 .vector_size = sizeof (u32),
2328 .n_errors = TCP_N_ERROR,
2329 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2330 .error_strings = tcp_error_strings,
2331 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2333 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2334 foreach_tcp6_output_next
2337 .format_buffer = format_tcp_header,
2338 .format_trace = format_tcp_tx_trace,
2342 typedef enum _tcp_reset_next
2344 TCP_RESET_NEXT_DROP,
2345 TCP_RESET_NEXT_IP_LOOKUP,
2349 #define foreach_tcp4_reset_next \
2350 _(DROP, "error-drop") \
2351 _(IP_LOOKUP, "ip4-lookup")
2353 #define foreach_tcp6_reset_next \
2354 _(DROP, "error-drop") \
2355 _(IP_LOOKUP, "ip6-lookup")
2358 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2359 vlib_frame_t * from_frame, u8 is_ip4)
2361 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2362 u32 n_left_from, next_index, *from, *to_next;
2364 from = vlib_frame_vector_args (from_frame);
2365 n_left_from = from_frame->n_vectors;
2367 next_index = node->cached_next_index;
2369 while (n_left_from > 0)
2373 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2375 while (n_left_from > 0 && n_left_to_next > 0)
2387 n_left_to_next -= 1;
2389 b0 = vlib_get_buffer (vm, bi0);
2390 tcp_make_reset_in_place (vm, b0, is_ip4);
2392 /* Prepare to send to IP lookup */
2393 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2395 b0->error = node->errors[error0];
2396 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2397 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2399 th0 = vlib_buffer_get_current (b0);
2401 th0 = ip4_next_header ((ip4_header_t *) th0);
2403 th0 = ip6_next_header ((ip6_header_t *) th0);
2404 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2405 clib_memcpy_fast (&t0->tcp_header, th0,
2406 sizeof (t0->tcp_header));
2409 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2410 n_left_to_next, bi0, next0);
2412 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2414 return from_frame->n_vectors;
2417 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2418 vlib_frame_t * from_frame)
2420 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2423 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2424 vlib_frame_t * from_frame)
2426 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2430 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2431 .name = "tcp4-reset",
2432 .vector_size = sizeof (u32),
2433 .n_errors = TCP_N_ERROR,
2434 .error_strings = tcp_error_strings,
2435 .n_next_nodes = TCP_RESET_N_NEXT,
2437 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2438 foreach_tcp4_reset_next
2441 .format_trace = format_tcp_tx_trace,
2446 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2447 .name = "tcp6-reset",
2448 .vector_size = sizeof (u32),
2449 .n_errors = TCP_N_ERROR,
2450 .error_strings = tcp_error_strings,
2451 .n_next_nodes = TCP_RESET_N_NEXT,
2453 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2454 foreach_tcp6_reset_next
2457 .format_trace = format_tcp_tx_trace,
2462 * fd.io coding-style-patch-verification: ON
2465 * eval: (c-set-style "gnu")