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>
19 typedef enum _tcp_output_next
22 TCP_OUTPUT_NEXT_IP_LOOKUP,
23 TCP_OUTPUT_NEXT_IP_REWRITE,
24 TCP_OUTPUT_NEXT_IP_ARP,
28 #define foreach_tcp4_output_next \
29 _ (DROP, "error-drop") \
30 _ (IP_LOOKUP, "ip4-lookup") \
31 _ (IP_REWRITE, "ip4-rewrite") \
34 #define foreach_tcp6_output_next \
35 _ (DROP, "error-drop") \
36 _ (IP_LOOKUP, "ip6-lookup") \
37 _ (IP_REWRITE, "ip6-rewrite") \
38 _ (IP_ARP, "ip6-discover-neighbor")
40 static char *tcp_error_strings[] = {
41 #define tcp_error(n,s) s,
42 #include <vnet/tcp/tcp_error.def>
48 tcp_header_t tcp_header;
49 tcp_connection_t tcp_connection;
53 format_tcp_tx_trace (u8 * s, va_list * args)
55 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
56 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
57 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
58 u32 indent = format_get_indent (s);
60 s = format (s, "%U\n%U%U",
61 format_tcp_header, &t->tcp_header, 128,
62 format_white_space, indent,
63 format_tcp_connection, &t->tcp_connection, 1);
68 #ifndef CLIB_MARCH_VARIANT
70 tcp_window_compute_scale (u32 window)
73 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
79 * TCP's initial window
82 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
84 /* RFC 6928 recommends the value lower. However at the time our connections
85 * are initialized, fifos may not be allocated. Therefore, advertise the
86 * smallest possible unscaled window size and update once fifos are
87 * assigned to the session.
90 tcp_update_rcv_mss (tc);
91 TCP_IW_N_SEGMENTS * tc->mss;
93 return tcp_cfg.min_rx_fifo;
97 * Compute initial window and scale factor. As per RFC1323, window field in
98 * SYN and SYN-ACK segments is never scaled.
101 tcp_initial_window_to_advertise (tcp_connection_t * tc)
103 /* Compute rcv wscale only if peer advertised support for it */
104 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
105 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
107 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
109 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
113 tcp_update_rcv_wnd (tcp_connection_t * tc)
115 u32 available_space, wnd;
118 ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection));
121 * Figure out how much space we have available
123 available_space = transport_max_rx_enqueue (&tc->connection);
124 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
131 * Use the above and what we know about what we've previously advertised
132 * to compute the new window
134 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
136 /* Bad. Thou shalt not shrink */
137 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
139 wnd = clib_max (observed_wnd, 0);
140 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
144 wnd = available_space;
147 /* Make sure we have a multiple of rcv_wscale */
148 if (wnd && tc->rcv_wscale)
150 wnd &= ~((1 << tc->rcv_wscale) - 1);
152 wnd = 1 << tc->rcv_wscale;
155 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
159 * Compute and return window to advertise, scaled as per RFC1323
162 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
164 if (state < TCP_STATE_ESTABLISHED)
165 return tcp_initial_window_to_advertise (tc);
167 tcp_update_rcv_wnd (tc);
168 return tc->rcv_wnd >> tc->rcv_wscale;
172 * Write TCP options to segment.
175 tcp_options_write (u8 * data, tcp_options_t * opts)
178 u32 buf, seq_len = 4;
180 if (tcp_opts_mss (opts))
182 *data++ = TCP_OPTION_MSS;
183 *data++ = TCP_OPTION_LEN_MSS;
184 buf = clib_host_to_net_u16 (opts->mss);
185 clib_memcpy_fast (data, &buf, sizeof (opts->mss));
186 data += sizeof (opts->mss);
187 opts_len += TCP_OPTION_LEN_MSS;
190 if (tcp_opts_wscale (opts))
192 *data++ = TCP_OPTION_WINDOW_SCALE;
193 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
194 *data++ = opts->wscale;
195 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
198 if (tcp_opts_sack_permitted (opts))
200 *data++ = TCP_OPTION_SACK_PERMITTED;
201 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
202 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
205 if (tcp_opts_tstamp (opts))
207 *data++ = TCP_OPTION_TIMESTAMP;
208 *data++ = TCP_OPTION_LEN_TIMESTAMP;
209 buf = clib_host_to_net_u32 (opts->tsval);
210 clib_memcpy_fast (data, &buf, sizeof (opts->tsval));
211 data += sizeof (opts->tsval);
212 buf = clib_host_to_net_u32 (opts->tsecr);
213 clib_memcpy_fast (data, &buf, sizeof (opts->tsecr));
214 data += sizeof (opts->tsecr);
215 opts_len += TCP_OPTION_LEN_TIMESTAMP;
218 if (tcp_opts_sack (opts))
222 if (opts->n_sack_blocks != 0)
224 *data++ = TCP_OPTION_SACK_BLOCK;
225 *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
226 for (i = 0; i < opts->n_sack_blocks; i++)
228 buf = clib_host_to_net_u32 (opts->sacks[i].start);
229 clib_memcpy_fast (data, &buf, seq_len);
231 buf = clib_host_to_net_u32 (opts->sacks[i].end);
232 clib_memcpy_fast (data, &buf, seq_len);
235 opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
239 /* Terminate TCP options */
242 *data++ = TCP_OPTION_EOL;
243 opts_len += TCP_OPTION_LEN_EOL;
246 /* Pad with zeroes to a u32 boundary */
249 *data++ = TCP_OPTION_NOOP;
250 opts_len += TCP_OPTION_LEN_NOOP;
256 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
260 opts->flags |= TCP_OPTS_FLAG_MSS;
262 len += TCP_OPTION_LEN_MSS;
264 opts->flags |= TCP_OPTS_FLAG_WSCALE;
265 opts->wscale = tc->rcv_wscale;
266 len += TCP_OPTION_LEN_WINDOW_SCALE;
268 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
269 opts->tsval = tcp_time_now ();
271 len += TCP_OPTION_LEN_TIMESTAMP;
275 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
276 len += TCP_OPTION_LEN_SACK_PERMITTED;
279 /* Align to needed boundary */
280 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
285 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
289 opts->flags |= TCP_OPTS_FLAG_MSS;
291 len += TCP_OPTION_LEN_MSS;
293 if (tcp_opts_wscale (&tc->rcv_opts))
295 opts->flags |= TCP_OPTS_FLAG_WSCALE;
296 opts->wscale = tc->rcv_wscale;
297 len += TCP_OPTION_LEN_WINDOW_SCALE;
300 if (tcp_opts_tstamp (&tc->rcv_opts))
302 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
303 opts->tsval = tcp_time_now ();
304 opts->tsecr = tc->tsval_recent;
305 len += TCP_OPTION_LEN_TIMESTAMP;
308 if (tcp_opts_sack_permitted (&tc->rcv_opts))
310 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
311 len += TCP_OPTION_LEN_SACK_PERMITTED;
314 /* Align to needed boundary */
315 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
320 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
326 if (tcp_opts_tstamp (&tc->rcv_opts))
328 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
329 opts->tsval = tcp_tstamp (tc);
330 opts->tsecr = tc->tsval_recent;
331 len += TCP_OPTION_LEN_TIMESTAMP;
333 if (tcp_opts_sack_permitted (&tc->rcv_opts))
335 if (vec_len (tc->snd_sacks))
337 opts->flags |= TCP_OPTS_FLAG_SACK;
338 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
339 tc->snd_sack_pos = 0;
340 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
341 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
342 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
343 TCP_OPTS_MAX_SACK_BLOCKS);
344 tc->snd_sack_pos += opts->n_sack_blocks;
345 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
349 /* Align to needed boundary */
350 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
355 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
360 case TCP_STATE_ESTABLISHED:
361 case TCP_STATE_CLOSE_WAIT:
362 case TCP_STATE_FIN_WAIT_1:
363 case TCP_STATE_LAST_ACK:
364 case TCP_STATE_CLOSING:
365 case TCP_STATE_FIN_WAIT_2:
366 case TCP_STATE_TIME_WAIT:
367 case TCP_STATE_CLOSED:
368 return tcp_make_established_options (tc, opts);
369 case TCP_STATE_SYN_RCVD:
370 return tcp_make_synack_options (tc, opts);
371 case TCP_STATE_SYN_SENT:
372 return tcp_make_syn_options (tc, opts);
374 clib_warning ("State not handled! %d", state);
380 * Update burst send vars
382 * - Updates snd_mss to reflect the effective segment size that we can send
383 * by taking into account all TCP options, including SACKs.
384 * - Cache 'on the wire' options for reuse
385 * - Updates receive window which can be reused for a burst.
387 * This should *only* be called when doing bursts
390 tcp_update_burst_snd_vars (tcp_connection_t * tc)
392 tcp_main_t *tm = &tcp_main;
394 /* Compute options to be used for connection. These may be reused when
395 * sending data or to compute the effective mss (snd_mss) */
396 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
397 TCP_STATE_ESTABLISHED);
399 /* XXX check if MTU has been updated */
400 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
401 ASSERT (tc->snd_mss > 0);
403 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
406 tcp_update_rcv_wnd (tc);
408 if (tc->flags & TCP_CONN_RATE_SAMPLE)
409 tc->flags |= TCP_CONN_TRACK_BURST;
411 if (tc->snd_una == tc->snd_nxt)
412 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
415 #endif /* CLIB_MARCH_VARIANT */
418 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
420 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
421 vlib_buffer_free_one (vm, b->next_buffer);
422 /* Zero all flags but free list index and trace flag */
423 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
425 b->current_length = 0;
426 b->total_length_not_including_first_buffer = 0;
427 vnet_buffer (b)->tcp.flags = 0;
429 /* Leave enough space for headers */
430 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
433 #ifndef CLIB_MARCH_VARIANT
435 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
437 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
438 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
439 b->total_length_not_including_first_buffer = 0;
441 vnet_buffer (b)->tcp.flags = 0;
442 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
443 /* Leave enough space for headers */
444 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
451 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
454 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
455 u8 tcp_opts_len, tcp_hdr_opts_len;
459 wnd = tcp_window_to_advertise (tc, state);
461 /* Make and write options */
462 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
463 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
465 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
466 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
468 tcp_options_write ((u8 *) (th + 1), snd_opts);
469 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
472 tcp_zero_rwnd_sent_on (tc);
474 tcp_zero_rwnd_sent_off (tc);
478 * Convert buffer to ACK
481 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
483 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
484 TCP_EVT (TCP_EVT_ACK_SENT, tc);
485 tc->rcv_las = tc->rcv_nxt;
489 * Convert buffer to FIN-ACK
492 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
494 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
498 * Convert buffer to SYN
501 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
503 u8 tcp_hdr_opts_len, tcp_opts_len;
506 tcp_options_t snd_opts;
508 initial_wnd = tcp_initial_window_to_advertise (tc);
510 /* Make and write options */
511 clib_memset (&snd_opts, 0, sizeof (snd_opts));
512 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
513 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
515 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
516 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
518 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
519 tcp_options_write ((u8 *) (th + 1), &snd_opts);
523 * Convert buffer to SYN-ACK
526 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
528 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
529 u8 tcp_opts_len, tcp_hdr_opts_len;
533 clib_memset (snd_opts, 0, sizeof (*snd_opts));
534 initial_wnd = tcp_initial_window_to_advertise (tc);
535 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
536 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
538 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
539 tc->rcv_nxt, tcp_hdr_opts_len,
540 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
541 tcp_options_write ((u8 *) (th + 1), snd_opts);
543 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
547 tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
548 u8 is_ip4, u32 fib_index, u8 flush)
550 vlib_main_t *vm = wrk->vm;
551 u32 *to_next, next_index;
554 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
557 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
558 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
560 /* Send to IP lookup */
561 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
562 tcp_trajectory_add_start (b, 1);
564 f = wrk->ip_lookup_tx_frames[!is_ip4];
567 f = vlib_get_frame_to_node (vm, next_index);
569 wrk->ip_lookup_tx_frames[!is_ip4] = f;
572 to_next = vlib_frame_vector_args (f);
573 to_next[f->n_vectors] = bi;
575 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
577 vlib_put_frame_to_node (vm, next_index, f);
578 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
583 tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b,
584 u32 bi, u8 is_ip4, u32 fib_index)
586 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1);
590 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
591 u8 is_ip4, u32 fib_index)
593 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0);
594 if (wrk->vm->thread_index == 0 && vlib_num_workers ())
595 session_flush_frames_main_thread (wrk->vm);
599 tcp_enqueue_to_output_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
602 u32 *to_next, next_index;
605 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
608 /* Decide where to send the packet */
609 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
610 tcp_trajectory_add_start (b, 2);
612 /* Get frame to v4/6 output node */
613 f = wrk->tx_frames[!is_ip4];
616 f = vlib_get_frame_to_node (wrk->vm, next_index);
618 wrk->tx_frames[!is_ip4] = f;
620 to_next = vlib_frame_vector_args (f);
621 to_next[f->n_vectors] = bi;
623 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
625 vlib_put_frame_to_node (wrk->vm, next_index, f);
626 wrk->tx_frames[!is_ip4] = 0;
631 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
634 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 0);
638 tcp_enqueue_to_output_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
641 tcp_enqueue_to_output_i (wrk, b, bi, is_ip4, 1);
643 #endif /* CLIB_MARCH_VARIANT */
646 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
647 tcp_state_t state, u8 thread_index, u8 is_ip4)
652 ip4_address_t src_ip40, dst_ip40;
653 ip6_address_t src_ip60, dst_ip60;
654 u16 src_port, dst_port;
659 /* Find IP and TCP headers */
660 th0 = tcp_buffer_hdr (b0);
662 /* Save src and dst ip */
665 ih4 = vlib_buffer_get_current (b0);
666 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
667 src_ip40.as_u32 = ih4->src_address.as_u32;
668 dst_ip40.as_u32 = ih4->dst_address.as_u32;
672 ih6 = vlib_buffer_get_current (b0);
673 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
674 clib_memcpy_fast (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
675 clib_memcpy_fast (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
678 src_port = th0->src_port;
679 dst_port = th0->dst_port;
681 /* Try to determine what/why we're actually resetting */
682 if (state == TCP_STATE_CLOSED)
687 tmp = clib_net_to_host_u32 (th0->seq_number);
689 /* Got a SYN for no listener. */
690 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
691 ack = clib_host_to_net_u32 (tmp + 1);
696 flags = TCP_FLAG_RST;
697 seq = th0->ack_number;
701 tcp_reuse_buffer (vm, b0);
702 tcp_trajectory_add_start (b0, 4);
703 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
704 sizeof (tcp_header_t), flags, 0);
708 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
710 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
715 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
717 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
724 #ifndef CLIB_MARCH_VARIANT
726 * Send reset without reusing existing buffer
728 * It extracts connection info out of original packet
731 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
732 u32 thread_index, u8 is_ip4)
734 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
735 vlib_main_t *vm = wrk->vm;
737 u32 bi, sw_if_index, fib_index;
738 u8 tcp_hdr_len, flags = 0;
739 tcp_header_t *th, *pkt_th;
741 ip4_header_t *ih4, *pkt_ih4;
742 ip6_header_t *ih6, *pkt_ih6;
743 fib_protocol_t fib_proto;
745 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
748 b = vlib_get_buffer (vm, bi);
749 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
750 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
751 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
752 tcp_init_buffer (vm, b);
754 /* Make and write options */
755 tcp_hdr_len = sizeof (tcp_header_t);
759 pkt_ih4 = vlib_buffer_get_current (pkt);
760 pkt_th = ip4_next_header (pkt_ih4);
764 pkt_ih6 = vlib_buffer_get_current (pkt);
765 pkt_th = ip6_next_header (pkt_ih6);
768 if (tcp_ack (pkt_th))
770 flags = TCP_FLAG_RST;
771 seq = pkt_th->ack_number;
772 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
776 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
778 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
781 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
782 seq, ack, tcp_hdr_len, flags, 0);
784 /* Swap src and dst ip */
787 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
788 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
789 &pkt_ih4->src_address, IP_PROTOCOL_TCP, 1);
790 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
795 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
797 ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
798 &pkt_ih6->src_address, IP_PROTOCOL_TCP);
799 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
803 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index);
804 TCP_EVT (TCP_EVT_RST_SENT, tc);
805 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
806 TCP_ERROR_RST_SENT, 1);
810 * Build and set reset packet for connection
813 tcp_send_reset (tcp_connection_t * tc)
815 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
816 vlib_main_t *vm = wrk->vm;
820 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
823 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
825 b = vlib_get_buffer (vm, bi);
826 tcp_init_buffer (vm, b);
828 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
829 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
830 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
831 flags = TCP_FLAG_RST;
832 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
833 tc->rcv_nxt, tcp_hdr_opts_len, flags,
835 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
836 ASSERT (opts_write_len == tc->snd_opts_len);
837 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
838 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
839 TCP_EVT (TCP_EVT_RST_SENT, tc);
840 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
841 TCP_ERROR_RST_SENT, 1);
845 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
848 tcp_header_t *th = vlib_buffer_get_current (b);
849 vlib_main_t *vm = wrk->vm;
853 ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
854 &tc->c_rmt_ip4, IP_PROTOCOL_TCP, 1);
855 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
862 ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
863 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
864 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
872 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
873 * The packet is not forwarded through tcpx_output to avoid doing lookups
874 * in the half_open pool.
877 tcp_send_syn (tcp_connection_t * tc)
879 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
880 vlib_main_t *vm = wrk->vm;
885 * Setup retransmit and establish timers before requesting buffer
886 * such that we can return if we've ran out.
888 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
889 tc->rto * TCP_TO_TIMER_TICK);
891 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
893 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
897 b = vlib_get_buffer (vm, bi);
898 tcp_init_buffer (vm, b);
899 tcp_make_syn (tc, b);
901 /* Measure RTT with this */
902 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
903 tc->rtt_seq = tc->snd_nxt;
906 tcp_push_ip_hdr (wrk, tc, b);
907 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
908 TCP_EVT (TCP_EVT_SYN_SENT, tc);
912 tcp_send_synack (tcp_connection_t * tc)
914 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
915 vlib_main_t *vm = wrk->vm;
919 tcp_retransmit_timer_force_update (tc);
921 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
923 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
927 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
928 b = vlib_get_buffer (vm, bi);
929 tcp_init_buffer (vm, b);
930 tcp_make_synack (tc, b);
931 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
932 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
936 * Flush tx frame populated by retransmits and timer pops
939 tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4)
941 if (wrk->tx_frames[!is_ip4])
944 next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
945 vlib_put_frame_to_node (wrk->vm, next_index, wrk->tx_frames[!is_ip4]);
946 wrk->tx_frames[!is_ip4] = 0;
951 * Flush ip lookup tx frames populated by timer pops
954 tcp_flush_frame_to_ip_lookup (tcp_worker_ctx_t * wrk, u8 is_ip4)
956 if (wrk->ip_lookup_tx_frames[!is_ip4])
959 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
960 vlib_put_frame_to_node (wrk->vm, next_index,
961 wrk->ip_lookup_tx_frames[!is_ip4]);
962 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
967 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
970 tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk)
972 tcp_flush_frame_to_output (wrk, 1);
973 tcp_flush_frame_to_output (wrk, 0);
974 tcp_flush_frame_to_ip_lookup (wrk, 1);
975 tcp_flush_frame_to_ip_lookup (wrk, 0);
982 tcp_send_fin (tcp_connection_t * tc)
984 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
985 vlib_main_t *vm = wrk->vm;
990 fin_snt = tc->flags & TCP_CONN_FINSNT;
994 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
996 /* Out of buffers so program fin retransmit ASAP */
997 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1001 /* Make sure retransmit retries a fin not data */
1002 tc->flags |= TCP_CONN_FINSNT;
1006 tcp_retransmit_timer_force_update (tc);
1007 b = vlib_get_buffer (vm, bi);
1008 tcp_init_buffer (vm, b);
1009 tcp_make_fin (tc, b);
1010 tcp_enqueue_to_output_now (wrk, b, bi, tc->c_is_ip4);
1011 TCP_EVT (TCP_EVT_FIN_SENT, tc);
1012 /* Account for the FIN */
1016 tc->flags |= TCP_CONN_FINSNT;
1017 tc->flags &= ~TCP_CONN_FINPNDG;
1018 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
1023 * Push TCP header and update connection variables. Should only be called
1024 * for segments with data, not for 'control' packets.
1027 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
1028 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
1030 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
1031 u32 advertise_wnd, data_len;
1032 tcp_main_t *tm = &tcp_main;
1035 data_len = b->current_length;
1036 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1037 data_len += b->total_length_not_including_first_buffer;
1039 vnet_buffer (b)->tcp.flags = 0;
1040 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
1043 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1045 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
1048 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1050 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
1052 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
1054 if (seq_geq (tc->psh_seq, snd_nxt)
1055 && seq_lt (tc->psh_seq, snd_nxt + data_len))
1056 flags |= TCP_FLAG_PSH;
1058 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
1059 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1064 clib_memcpy_fast ((u8 *) (th + 1),
1065 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1070 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1071 ASSERT (len == tc->snd_opts_len);
1075 * Update connection variables
1079 tc->snd_nxt += data_len;
1080 tc->rcv_las = tc->rcv_nxt;
1082 tc->bytes_out += data_len;
1083 tc->data_segs_out += 1;
1085 TCP_EVT (TCP_EVT_PKTIZE, tc);
1089 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
1091 tcp_connection_t *tc = (tcp_connection_t *) tconn;
1093 if (tc->flags & TCP_CONN_TRACK_BURST)
1095 tcp_bt_check_app_limited (tc);
1096 tcp_bt_track_tx (tc);
1097 tc->flags &= ~TCP_CONN_TRACK_BURST;
1100 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1101 /* update_snd_nxt */ 1);
1103 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1104 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1105 /* If not tracking an ACK, start tracking */
1106 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1108 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1109 tc->rtt_seq = tc->snd_nxt;
1111 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1113 tcp_retransmit_timer_set (tc);
1116 tcp_trajectory_add_start (b, 3);
1121 tcp_send_ack (tcp_connection_t * tc)
1123 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1124 vlib_main_t *vm = wrk->vm;
1128 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1130 tcp_update_rcv_wnd (tc);
1133 b = vlib_get_buffer (vm, bi);
1134 tcp_init_buffer (vm, b);
1135 tcp_make_ack (tc, b);
1136 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1140 tcp_program_ack (tcp_connection_t * tc)
1142 if (!(tc->flags & TCP_CONN_SNDACK))
1144 session_add_self_custom_tx_evt (&tc->connection, 1);
1145 tc->flags |= TCP_CONN_SNDACK;
1150 tcp_program_dupack (tcp_connection_t * tc)
1152 if (!(tc->flags & TCP_CONN_SNDACK))
1154 session_add_self_custom_tx_evt (&tc->connection, 1);
1155 tc->flags |= TCP_CONN_SNDACK;
1157 if (tc->pending_dupacks < 255)
1158 tc->pending_dupacks += 1;
1162 tcp_program_retransmit (tcp_connection_t * tc)
1164 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1166 session_add_self_custom_tx_evt (&tc->connection, 0);
1167 tc->flags |= TCP_CONN_RXT_PENDING;
1172 * Delayed ack timer handler
1174 * Sends delayed ACK when timer expires
1177 tcp_timer_delack_handler (u32 index)
1179 u32 thread_index = vlib_get_thread_index ();
1180 tcp_connection_t *tc;
1182 tc = tcp_connection_get (index, thread_index);
1183 tc->timers[TCP_TIMER_DELACK] = TCP_TIMER_HANDLE_INVALID;
1188 * Send window update ack
1190 * Ensures that it will be sent only once, after a zero rwnd has been
1191 * advertised in a previous ack, and only if rwnd has grown beyond a
1192 * configurable value.
1195 tcp_send_window_update_ack (tcp_connection_t * tc)
1197 if (tcp_zero_rwnd_sent (tc))
1199 tcp_update_rcv_wnd (tc);
1200 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1202 tcp_zero_rwnd_sent_off (tc);
1203 tcp_program_ack (tc);
1209 * Allocate a new buffer and build a new tcp segment
1211 * @param wrk tcp worker
1212 * @param tc connection for which the segment will be allocated
1213 * @param offset offset of the first byte in the tx fifo
1214 * @param max_deq_byte segment size
1215 * @param[out] b pointer to buffer allocated
1217 * @return the number of bytes in the segment or 0 if buffer cannot be
1218 * allocated or no data available
1221 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1222 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1224 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1225 vlib_main_t *vm = wrk->vm;
1230 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1235 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1238 * Allocate and fill in buffer(s)
1241 /* Easy case, buffer size greater than mss */
1242 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1244 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1246 *b = vlib_get_buffer (vm, bi);
1247 data = tcp_init_buffer (vm, *b);
1248 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1250 ASSERT (n_bytes == max_deq_bytes);
1251 b[0]->current_length = n_bytes;
1252 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1253 /* burst */ 0, /* update_snd_nxt */ 0);
1255 /* Split mss into multiple buffers */
1258 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1259 u16 n_peeked, len_to_deq;
1260 vlib_buffer_t *chain_b, *prev_b;
1263 /* Make sure we have enough buffers */
1264 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1265 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1266 CLIB_CACHE_LINE_BYTES);
1267 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1268 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1271 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1275 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1276 data = tcp_init_buffer (vm, *b);
1277 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1279 TRANSPORT_MAX_HDRS_LEN);
1280 b[0]->current_length = n_bytes;
1281 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1282 b[0]->total_length_not_including_first_buffer = 0;
1283 max_deq_bytes -= n_bytes;
1286 for (i = 1; i < n_bufs_per_seg; i++)
1289 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1290 chain_bi = wrk->tx_buffers[--n_bufs];
1291 chain_b = vlib_get_buffer (vm, chain_bi);
1292 chain_b->current_data = 0;
1293 data = vlib_buffer_get_current (chain_b);
1294 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1297 ASSERT (n_peeked == len_to_deq);
1298 n_bytes += n_peeked;
1299 chain_b->current_length = n_peeked;
1300 chain_b->next_buffer = 0;
1302 /* update previous buffer */
1303 prev_b->next_buffer = chain_bi;
1304 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1306 max_deq_bytes -= n_peeked;
1307 b[0]->total_length_not_including_first_buffer += n_peeked;
1310 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1311 /* burst */ 0, /* update_snd_nxt */ 0);
1313 if (PREDICT_FALSE (n_bufs))
1315 clib_warning ("not all buffers consumed");
1316 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1320 ASSERT (n_bytes > 0);
1321 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1327 * Build a retransmit segment
1329 * @return the number of bytes in the segment or 0 if there's nothing to
1333 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1334 tcp_connection_t * tc, u32 offset,
1335 u32 max_deq_bytes, vlib_buffer_t ** b)
1337 u32 start, available_bytes;
1340 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1341 ASSERT (max_deq_bytes != 0);
1344 * Make sure we can retransmit something
1346 available_bytes = transport_max_tx_dequeue (&tc->connection);
1347 ASSERT (available_bytes >= offset);
1348 available_bytes -= offset;
1349 if (!available_bytes)
1352 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1353 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1355 /* Start is beyond snd_congestion */
1356 start = tc->snd_una + offset;
1357 if (seq_geq (start, tc->snd_congestion))
1360 /* Don't overshoot snd_congestion */
1361 if (seq_gt (start + max_deq_bytes, tc->snd_congestion))
1363 max_deq_bytes = tc->snd_congestion - start;
1364 if (max_deq_bytes == 0)
1368 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1372 tc->snd_rxt_bytes += n_bytes;
1374 if (tc->flags & TCP_CONN_RATE_SAMPLE)
1375 tcp_bt_track_rxt (tc, start, start + n_bytes);
1377 tc->bytes_retrans += n_bytes;
1378 tc->segs_retrans += 1;
1379 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1385 tcp_check_sack_reneging (tcp_connection_t * tc)
1387 sack_scoreboard_t *sb = &tc->sack_sb;
1388 sack_scoreboard_hole_t *hole;
1390 hole = scoreboard_first_hole (sb);
1391 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1394 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1398 * Reset congestion control, switch cwnd to loss window and try again.
1401 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1403 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1405 tc->prev_ssthresh = tc->ssthresh;
1406 tc->prev_cwnd = tc->cwnd;
1408 /* If we entrered loss without fast recovery, notify cc algo of the
1409 * congestion event such that it can update ssthresh and its state */
1410 if (!tcp_in_fastrecovery (tc))
1411 tcp_cc_congestion (tc);
1413 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1417 tc->cwnd_acc_bytes = 0;
1418 tc->tr_occurences += 1;
1419 tcp_recovery_on (tc);
1423 tcp_timer_retransmit_handler (u32 tc_index)
1425 u32 thread_index = vlib_get_thread_index ();
1426 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1427 vlib_main_t *vm = wrk->vm;
1428 tcp_connection_t *tc;
1429 vlib_buffer_t *b = 0;
1432 tc = tcp_connection_get (tc_index, thread_index);
1434 /* Note: the connection may have been closed and pool_put */
1435 if (PREDICT_FALSE (tc == 0 || tc->state == TCP_STATE_SYN_SENT))
1438 tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
1440 /* Wait-close and retransmit could pop at the same time */
1441 if (tc->state == TCP_STATE_CLOSED)
1444 if (tc->state >= TCP_STATE_ESTABLISHED)
1446 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1448 /* Lost FIN, retransmit and return */
1449 if (tc->flags & TCP_CONN_FINSNT)
1453 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1457 /* Shouldn't be here. This condition is tricky because it has to take
1458 * into account boff > 0 due to persist timeout. */
1459 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1460 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1461 && !tcp_flight_size (tc)))
1463 ASSERT (!tcp_in_recovery (tc));
1468 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1469 * to persist timer timeout */
1470 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1473 tcp_update_rto (tc);
1476 /* Peer is dead or network connectivity is lost. Close connection.
1477 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1478 * a min rto of 0.2s we need to retry about 8 times. */
1479 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1481 tcp_send_reset (tc);
1482 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1483 session_transport_closing_notify (&tc->connection);
1484 tcp_connection_timers_reset (tc);
1485 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1489 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1490 tcp_check_sack_reneging (tc);
1492 /* Update send congestion to make sure that rxt has data to send */
1493 tc->snd_congestion = tc->snd_nxt;
1495 /* Send the first unacked segment. If we're short on buffers, return
1496 * as soon as possible */
1497 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1500 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1504 bi = vlib_get_buffer_index (vm, b);
1505 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1507 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1508 tcp_retransmit_timer_force_update (tc);
1511 if (tc->rto_boff == 1)
1513 tcp_cc_init_rxt_timeout (tc);
1514 /* Record timestamp. Eifel detection algorithm RFC3522 */
1515 tc->snd_rxt_ts = tcp_tstamp (tc);
1518 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1519 scoreboard_init_high_rxt (&tc->sack_sb, tc->snd_una + tc->snd_mss);
1521 tcp_program_retransmit (tc);
1523 /* Retransmit SYN-ACK */
1524 else if (tc->state == TCP_STATE_SYN_RCVD)
1526 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1530 /* Passive open establish timeout */
1531 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1533 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1534 tcp_connection_timers_reset (tc);
1535 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
1539 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1541 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1546 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1547 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1549 tcp_retransmit_timer_force_update (tc);
1551 b = vlib_get_buffer (vm, bi);
1552 tcp_init_buffer (vm, b);
1553 tcp_make_synack (tc, b);
1554 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1556 /* Retransmit timer already updated, just enqueue to output */
1557 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1561 ASSERT (tc->state == TCP_STATE_CLOSED);
1567 * SYN retransmit timer handler. Active open only.
1570 tcp_timer_retransmit_syn_handler (u32 tc_index)
1572 u32 thread_index = vlib_get_thread_index ();
1573 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1574 vlib_main_t *vm = wrk->vm;
1575 tcp_connection_t *tc;
1576 vlib_buffer_t *b = 0;
1579 tc = tcp_half_open_connection_get (tc_index);
1581 /* Note: the connection may have transitioned to ESTABLISHED... */
1582 if (PREDICT_FALSE (tc == 0 || tc->state != TCP_STATE_SYN_SENT))
1585 tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
1587 /* Half-open connection actually moved to established but we were
1588 * waiting for syn retransmit to pop to call cleanup from the right
1590 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1592 if (tcp_half_open_connection_cleanup (tc))
1593 TCP_DBG ("could not remove half-open connection");
1597 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1600 /* Active open establish timeout */
1601 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1603 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
1604 tcp_connection_cleanup (tc);
1608 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1610 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1614 /* Try without increasing RTO a number of times. If this fails,
1615 * start growing RTO exponentially */
1617 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1618 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1620 b = vlib_get_buffer (vm, bi);
1621 tcp_init_buffer (vm, b);
1622 tcp_make_syn (tc, b);
1624 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1626 /* This goes straight to ipx_lookup */
1627 tcp_push_ip_hdr (wrk, tc, b);
1628 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1630 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1631 tc->rto * TCP_TO_TIMER_TICK);
1635 * Got 0 snd_wnd from peer, try to do something about it.
1639 tcp_timer_persist_handler (u32 index)
1641 u32 thread_index = vlib_get_thread_index ();
1642 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1643 u32 bi, max_snd_bytes, available_bytes, offset;
1644 tcp_main_t *tm = vnet_get_tcp_main ();
1645 vlib_main_t *vm = wrk->vm;
1646 tcp_connection_t *tc;
1651 tc = tcp_connection_get_if_valid (index, thread_index);
1655 /* Make sure timer handle is set to invalid */
1656 tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID;
1658 /* Problem already solved or worse */
1659 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1660 || (tc->flags & TCP_CONN_FINSNT))
1663 available_bytes = transport_max_tx_dequeue (&tc->connection);
1664 offset = tc->snd_nxt - tc->snd_una;
1666 /* Reprogram persist if no new bytes available to send. We may have data
1668 if (!available_bytes)
1670 tcp_persist_timer_set (tc);
1674 if (available_bytes <= offset)
1676 ASSERT (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
1680 /* Increment RTO backoff */
1682 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1685 * Try to force the first unsent segment (or buffer)
1687 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1689 tcp_persist_timer_set (tc);
1692 b = vlib_get_buffer (vm, bi);
1693 data = tcp_init_buffer (vm, b);
1695 tcp_validate_txf_size (tc, offset);
1696 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1697 max_snd_bytes = clib_min (tc->snd_mss,
1698 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1699 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1701 b->current_length = n_bytes;
1702 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1703 || tc->snd_nxt == tc->snd_una_max
1704 || tc->rto_boff > 1));
1706 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1707 /* burst */ 0, /* update_snd_nxt */ 1);
1708 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1709 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1710 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1712 /* Just sent new data, enable retransmit */
1713 tcp_retransmit_timer_update (tc);
1717 * Retransmit first unacked segment
1720 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1722 vlib_main_t *vm = wrk->vm;
1726 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1728 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1732 bi = vlib_get_buffer_index (vm, b);
1733 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1739 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1742 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1743 vlib_main_t *vm = wrk->vm;
1744 vlib_buffer_t *b = 0;
1746 offset = tc->snd_nxt - tc->snd_una;
1747 available_wnd = tc->snd_wnd - offset;
1748 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1750 while (n_segs < burst_size)
1752 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1756 bi = vlib_get_buffer_index (vm, b);
1757 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1758 offset += n_written;
1761 tc->snd_nxt += n_written;
1762 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1770 * Estimate send space using proportional rate reduction (RFC6937)
1773 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1778 pipe = tcp_flight_size (tc);
1779 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1781 if (pipe > tc->ssthresh)
1783 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1788 int limit = tc->prr_delivered - prr_out + tc->snd_mss;
1789 space = clib_min (tc->ssthresh - pipe, limit);
1791 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1795 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1796 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1797 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1800 * Do retransmit with SACKs
1803 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1806 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1807 sack_scoreboard_hole_t *hole;
1808 vlib_main_t *vm = wrk->vm;
1809 vlib_buffer_t *b = 0;
1810 sack_scoreboard_t *sb;
1813 u8 snd_limited = 0, can_rescue = 0;
1815 ASSERT (tcp_in_cong_recovery (tc));
1817 if (tcp_in_recovery (tc))
1818 snd_space = tcp_available_cc_snd_space (tc);
1820 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1822 if (snd_space < tc->snd_mss)
1824 /* We're cc constrained so don't accumulate tokens */
1825 transport_connection_tx_pacer_reset_bucket (&tc->connection,
1827 clib_time.last_cpu_time);
1831 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1833 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1835 max_deq = transport_max_tx_dequeue (&tc->connection);
1836 max_deq -= tc->snd_nxt - tc->snd_una;
1838 while (snd_space > 0 && n_segs < burst_size)
1840 hole = scoreboard_next_rxt_hole (sb, hole, max_deq, &can_rescue,
1844 /* We are out of lost holes to retransmit so send some new data. */
1847 u32 n_segs_new, av_window;
1848 av_window = tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1849 snd_space = clib_min (snd_space, av_window);
1850 snd_space = clib_min (max_deq, snd_space);
1851 burst_size = clib_min (burst_size - n_segs,
1852 snd_space / tc->snd_mss);
1853 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1854 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1855 if (max_deq > n_segs_new * tc->snd_mss)
1856 tcp_program_retransmit (tc);
1858 n_segs += n_segs_new;
1862 if (tcp_in_recovery (tc) || !can_rescue
1863 || scoreboard_rescue_rxt_valid (sb, tc))
1866 /* If rescue rxt undefined or less than snd_una then one segment of
1867 * up to SMSS octets that MUST include the highest outstanding
1868 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1869 * RecoveryPoint. HighRxt MUST NOT be updated.
1871 max_bytes = clib_min (tc->snd_mss,
1872 tc->snd_congestion - tc->snd_una);
1873 max_bytes = clib_min (max_bytes, snd_space);
1874 offset = tc->snd_congestion - tc->snd_una - max_bytes;
1875 sb->rescue_rxt = tc->snd_congestion;
1876 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1881 bi = vlib_get_buffer_index (vm, b);
1882 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1887 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1888 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1892 offset = sb->high_rxt - tc->snd_una;
1893 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1895 ASSERT (n_written <= snd_space);
1897 /* Nothing left to retransmit */
1901 bi = vlib_get_buffer_index (vm, b);
1902 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1904 sb->high_rxt += n_written;
1905 snd_space -= n_written;
1910 tcp_program_retransmit (tc);
1918 * Fast retransmit without SACK info
1921 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1924 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now;
1925 vlib_main_t *vm = wrk->vm;
1926 int snd_space, n_segs = 0;
1929 ASSERT (tcp_in_fastrecovery (tc));
1930 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1932 snd_space = tcp_available_cc_snd_space (tc);
1934 if (!tcp_fastrecovery_first (tc))
1937 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1939 while (snd_space > 0 && n_segs < burst_size)
1941 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1944 /* Nothing left to retransmit */
1948 bi = vlib_get_buffer_index (vm, b);
1949 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1950 snd_space -= n_written;
1951 offset += n_written;
1955 if (n_segs == burst_size)
1960 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1961 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1964 max_deq = transport_max_tx_dequeue (&tc->connection);
1965 max_deq -= tc->snd_nxt - tc->snd_una;
1968 snd_space = clib_min (max_deq, snd_space);
1969 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1970 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1971 if (max_deq > n_segs_now * tc->snd_mss)
1972 tcp_program_retransmit (tc);
1973 n_segs += n_segs_now;
1977 tcp_fastrecovery_first_off (tc);
1982 * Do fast retransmit
1985 tcp_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, u32 burst_size)
1987 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1988 return tcp_retransmit_sack (wrk, tc, burst_size);
1990 return tcp_retransmit_no_sack (wrk, tc, burst_size);
1994 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1998 if (!tc->pending_dupacks)
2004 /* If we're supposed to send dupacks but have no ooo data
2005 * send only one ack */
2006 if (!vec_len (tc->snd_sacks))
2012 /* Start with first sack block */
2013 tc->snd_sack_pos = 0;
2015 /* Generate enough dupacks to cover all sack blocks. Do not generate
2016 * more sacks than the number of packets received. But do generate at
2017 * least 3, i.e., the number needed to signal congestion, if needed. */
2018 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
2019 n_acks = clib_min (n_acks, tc->pending_dupacks);
2020 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
2021 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
2024 if (n_acks < max_burst_size)
2026 tc->pending_dupacks = 0;
2027 tc->snd_sack_pos = 0;
2028 tc->dupacks_out += n_acks;
2033 TCP_DBG ("constrained by burst size");
2034 tc->pending_dupacks = n_acks - max_burst_size;
2035 tc->dupacks_out += max_burst_size;
2036 tcp_program_dupack (tc);
2037 return max_burst_size;
2042 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
2044 u32 n_segs = 0, burst_size, sent_bytes, burst_bytes;
2045 tcp_worker_ctx_t *wrk;
2047 wrk = tcp_get_worker (tc->c_thread_index);
2048 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection,
2050 clib_time.last_cpu_time);
2051 burst_size = clib_min (max_burst_size, burst_bytes / tc->snd_mss);
2054 tcp_program_retransmit (tc);
2058 n_segs = tcp_retransmit (wrk, tc, burst_size);
2059 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2060 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
2065 tcp_session_custom_tx (void *conn, u32 max_burst_size)
2067 tcp_connection_t *tc = (tcp_connection_t *) conn;
2070 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2072 tc->flags &= ~TCP_CONN_RXT_PENDING;
2073 n_segs = tcp_do_retransmit (tc, max_burst_size);
2074 max_burst_size -= n_segs;
2077 if (!(tc->flags & TCP_CONN_SNDACK))
2080 tc->flags &= ~TCP_CONN_SNDACK;
2082 /* We have retransmitted packets and no dupack */
2083 if (n_segs && !tc->pending_dupacks)
2086 if (!max_burst_size)
2088 tcp_program_ack (tc);
2089 return max_burst_size;
2092 n_segs += tcp_send_acks (tc, max_burst_size);
2096 #endif /* CLIB_MARCH_VARIANT */
2099 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2100 u16 * next0, u32 * error0)
2102 ip_adjacency_t *adj;
2105 /* Not thread safe but as long as the connection exists the adj should
2107 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2109 if (ai == ADJ_INDEX_INVALID)
2111 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2112 *next0 = TCP_OUTPUT_NEXT_DROP;
2113 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2118 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2119 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2120 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2121 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2124 *next0 = TCP_OUTPUT_NEXT_DROP;
2125 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2127 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2131 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2132 u32 * to_next, u32 n_bufs)
2134 u32 n_trace = vlib_get_trace_count (vm, node);
2135 tcp_connection_t *tc;
2141 for (i = 0; i < clib_min (n_trace, n_bufs); i++)
2143 b = vlib_get_buffer (vm, to_next[i]);
2144 th = vlib_buffer_get_current (b);
2145 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2147 t = vlib_add_trace (vm, node, b, sizeof (*t));
2148 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2149 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2154 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2155 tcp_connection_t * tc0, u8 is_ip4)
2157 tcp_header_t *th0 = 0;
2159 th0 = vlib_buffer_get_current (b0);
2160 TCP_EVT (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length);
2163 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2164 IP_PROTOCOL_TCP, 1);
2165 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
2166 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
2172 ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6,
2173 &tc0->c_rmt_ip6, IP_PROTOCOL_TCP);
2174 b0->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
2175 vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data;
2176 vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
2178 VNET_BUFFER_F_L3_HDR_OFFSET_VALID | VNET_BUFFER_F_L4_HDR_OFFSET_VALID;
2184 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2186 if (PREDICT_TRUE (!(b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)))
2189 b->current_length + b->total_length_not_including_first_buffer -
2190 sizeof (tcp_header_t) - tc->snd_opts_len;
2192 if (data_len > tc->snd_mss)
2194 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2195 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2196 b->flags |= VNET_BUFFER_F_GSO;
2197 vnet_buffer2 (b)->gso_l4_hdr_sz =
2198 sizeof (tcp_header_t) + tc->snd_opts_len;
2199 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2204 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2205 vlib_node_runtime_t * error_node, u16 * next0,
2208 /* If next_index is not drop use it */
2209 if (tc0->next_node_index)
2211 *next0 = tc0->next_node_index;
2212 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2216 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2219 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2220 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2226 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2227 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2229 if (PREDICT_FALSE (error0))
2231 b0->error = error_node->errors[error0];
2236 if (!TCP_ALWAYS_ACK)
2237 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
2243 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2244 vlib_frame_t * frame, int is_ip4)
2246 u32 n_left_from, *from, thread_index = vm->thread_index;
2247 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2248 u16 nexts[VLIB_FRAME_SIZE], *next;
2249 vlib_node_runtime_t *error_node;
2251 error_node = vlib_node_get_runtime (vm, tcp_node_index (output, is_ip4));
2253 from = vlib_frame_vector_args (frame);
2254 n_left_from = frame->n_vectors;
2255 tcp_set_time_now (tcp_get_worker (thread_index));
2257 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2258 tcp46_output_trace_frame (vm, node, from, n_left_from);
2260 vlib_get_buffers (vm, from, bufs, n_left_from);
2264 while (n_left_from >= 4)
2266 tcp_connection_t *tc0, *tc1;
2269 vlib_prefetch_buffer_header (b[2], STORE);
2270 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2272 vlib_prefetch_buffer_header (b[3], STORE);
2273 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2276 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2278 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2281 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2283 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2284 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2286 tcp_check_if_gso (tc0, b[0]);
2287 tcp_check_if_gso (tc1, b[1]);
2289 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2290 tcp_output_handle_packet (tc1, b[1], error_node, &next[1], is_ip4);
2296 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2297 tcp_check_if_gso (tc0, b[0]);
2298 tcp_output_handle_packet (tc0, b[0], error_node, &next[0],
2303 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2304 next[0] = TCP_OUTPUT_NEXT_DROP;
2308 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2309 tcp_check_if_gso (tc1, b[1]);
2310 tcp_output_handle_packet (tc1, b[1], error_node, &next[1],
2315 b[1]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2316 next[1] = TCP_OUTPUT_NEXT_DROP;
2324 while (n_left_from > 0)
2326 tcp_connection_t *tc0;
2328 if (n_left_from > 1)
2330 vlib_prefetch_buffer_header (b[1], STORE);
2331 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2334 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2337 if (PREDICT_TRUE (tc0 != 0))
2339 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2340 tcp_check_if_gso (tc0, b[0]);
2341 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2345 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2346 next[0] = TCP_OUTPUT_NEXT_DROP;
2354 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2355 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2356 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2357 return frame->n_vectors;
2360 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2361 vlib_frame_t * from_frame)
2363 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2366 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2367 vlib_frame_t * from_frame)
2369 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2373 VLIB_REGISTER_NODE (tcp4_output_node) =
2375 .name = "tcp4-output",
2376 /* Takes a vector of packets. */
2377 .vector_size = sizeof (u32),
2378 .n_errors = TCP_N_ERROR,
2379 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2380 .error_strings = tcp_error_strings,
2381 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2383 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2384 foreach_tcp4_output_next
2387 .format_buffer = format_tcp_header,
2388 .format_trace = format_tcp_tx_trace,
2393 VLIB_REGISTER_NODE (tcp6_output_node) =
2395 .name = "tcp6-output",
2396 /* Takes a vector of packets. */
2397 .vector_size = sizeof (u32),
2398 .n_errors = TCP_N_ERROR,
2399 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2400 .error_strings = tcp_error_strings,
2401 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2403 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2404 foreach_tcp6_output_next
2407 .format_buffer = format_tcp_header,
2408 .format_trace = format_tcp_tx_trace,
2412 typedef enum _tcp_reset_next
2414 TCP_RESET_NEXT_DROP,
2415 TCP_RESET_NEXT_IP_LOOKUP,
2419 #define foreach_tcp4_reset_next \
2420 _(DROP, "error-drop") \
2421 _(IP_LOOKUP, "ip4-lookup")
2423 #define foreach_tcp6_reset_next \
2424 _(DROP, "error-drop") \
2425 _(IP_LOOKUP, "ip6-lookup")
2428 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2429 vlib_frame_t * from_frame, u8 is_ip4)
2431 u32 n_left_from, next_index, *from, *to_next;
2432 u32 my_thread_index = vm->thread_index;
2434 from = vlib_frame_vector_args (from_frame);
2435 n_left_from = from_frame->n_vectors;
2437 next_index = node->cached_next_index;
2439 while (n_left_from > 0)
2443 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2445 while (n_left_from > 0 && n_left_to_next > 0)
2451 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2458 n_left_to_next -= 1;
2460 b0 = vlib_get_buffer (vm, bi0);
2462 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2463 my_thread_index, is_ip4))
2465 error0 = TCP_ERROR_LOOKUP_DROPS;
2466 next0 = TCP_RESET_NEXT_DROP;
2470 /* Prepare to send to IP lookup */
2471 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2472 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2475 b0->error = node->errors[error0];
2476 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2477 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2479 th0 = vlib_buffer_get_current (b0);
2481 th0 = ip4_next_header ((ip4_header_t *) th0);
2483 th0 = ip6_next_header ((ip6_header_t *) th0);
2484 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2485 clib_memcpy_fast (&t0->tcp_header, th0,
2486 sizeof (t0->tcp_header));
2489 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2490 n_left_to_next, bi0, next0);
2492 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2494 return from_frame->n_vectors;
2497 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2498 vlib_frame_t * from_frame)
2500 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2503 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2504 vlib_frame_t * from_frame)
2506 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2510 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2511 .name = "tcp4-reset",
2512 .vector_size = sizeof (u32),
2513 .n_errors = TCP_N_ERROR,
2514 .error_strings = tcp_error_strings,
2515 .n_next_nodes = TCP_RESET_N_NEXT,
2517 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2518 foreach_tcp4_reset_next
2521 .format_trace = format_tcp_tx_trace,
2526 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2527 .name = "tcp6-reset",
2528 .vector_size = sizeof (u32),
2529 .n_errors = TCP_N_ERROR,
2530 .error_strings = tcp_error_strings,
2531 .n_next_nodes = TCP_RESET_N_NEXT,
2533 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2534 foreach_tcp6_reset_next
2537 .format_trace = format_tcp_tx_trace,
2542 * fd.io coding-style-patch-verification: ON
2545 * eval: (c-set-style "gnu")