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 tcp_connection_t *tc = &t->tcp_connection;
59 u32 indent = format_get_indent (s);
61 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
62 format_tcp_state, tc->state, format_white_space, indent,
63 format_tcp_header, &t->tcp_header, 128);
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);
125 /* Make sure we have a multiple of 1 << rcv_wscale. We round down to
126 * avoid advertising a window larger than what can be buffered */
127 available_space = round_down_pow2 (available_space, 1 << tc->rcv_wscale);
129 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
136 * Use the above and what we know about what we've previously advertised
137 * to compute the new window
139 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
141 /* Bad. Thou shalt not shrink */
142 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
144 wnd = round_pow2 (clib_max (observed_wnd, 0), 1 << tc->rcv_wscale);
145 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
149 wnd = available_space;
152 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
156 * Compute and return window to advertise, scaled as per RFC1323
159 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
161 if (state < TCP_STATE_ESTABLISHED)
162 return tcp_initial_window_to_advertise (tc);
164 tcp_update_rcv_wnd (tc);
165 return tc->rcv_wnd >> tc->rcv_wscale;
169 * Write TCP options to segment.
172 tcp_options_write (u8 * data, tcp_options_t * opts)
175 u32 buf, seq_len = 4;
177 if (tcp_opts_mss (opts))
179 *data++ = TCP_OPTION_MSS;
180 *data++ = TCP_OPTION_LEN_MSS;
181 buf = clib_host_to_net_u16 (opts->mss);
182 clib_memcpy_fast (data, &buf, sizeof (opts->mss));
183 data += sizeof (opts->mss);
184 opts_len += TCP_OPTION_LEN_MSS;
187 if (tcp_opts_wscale (opts))
189 *data++ = TCP_OPTION_WINDOW_SCALE;
190 *data++ = TCP_OPTION_LEN_WINDOW_SCALE;
191 *data++ = opts->wscale;
192 opts_len += TCP_OPTION_LEN_WINDOW_SCALE;
195 if (tcp_opts_sack_permitted (opts))
197 *data++ = TCP_OPTION_SACK_PERMITTED;
198 *data++ = TCP_OPTION_LEN_SACK_PERMITTED;
199 opts_len += TCP_OPTION_LEN_SACK_PERMITTED;
202 if (tcp_opts_tstamp (opts))
204 *data++ = TCP_OPTION_TIMESTAMP;
205 *data++ = TCP_OPTION_LEN_TIMESTAMP;
206 buf = clib_host_to_net_u32 (opts->tsval);
207 clib_memcpy_fast (data, &buf, sizeof (opts->tsval));
208 data += sizeof (opts->tsval);
209 buf = clib_host_to_net_u32 (opts->tsecr);
210 clib_memcpy_fast (data, &buf, sizeof (opts->tsecr));
211 data += sizeof (opts->tsecr);
212 opts_len += TCP_OPTION_LEN_TIMESTAMP;
215 if (tcp_opts_sack (opts))
219 if (opts->n_sack_blocks != 0)
221 *data++ = TCP_OPTION_SACK_BLOCK;
222 *data++ = 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
223 for (i = 0; i < opts->n_sack_blocks; i++)
225 buf = clib_host_to_net_u32 (opts->sacks[i].start);
226 clib_memcpy_fast (data, &buf, seq_len);
228 buf = clib_host_to_net_u32 (opts->sacks[i].end);
229 clib_memcpy_fast (data, &buf, seq_len);
232 opts_len += 2 + opts->n_sack_blocks * TCP_OPTION_LEN_SACK_BLOCK;
236 /* Terminate TCP options */
239 *data++ = TCP_OPTION_EOL;
240 opts_len += TCP_OPTION_LEN_EOL;
243 /* Pad with zeroes to a u32 boundary */
246 *data++ = TCP_OPTION_NOOP;
247 opts_len += TCP_OPTION_LEN_NOOP;
253 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
257 opts->flags |= TCP_OPTS_FLAG_MSS;
259 len += TCP_OPTION_LEN_MSS;
261 opts->flags |= TCP_OPTS_FLAG_WSCALE;
262 opts->wscale = tc->rcv_wscale;
263 len += TCP_OPTION_LEN_WINDOW_SCALE;
265 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
266 opts->tsval = tcp_time_now ();
268 len += TCP_OPTION_LEN_TIMESTAMP;
272 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
273 len += TCP_OPTION_LEN_SACK_PERMITTED;
276 /* Align to needed boundary */
277 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
282 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
286 opts->flags |= TCP_OPTS_FLAG_MSS;
288 len += TCP_OPTION_LEN_MSS;
290 if (tcp_opts_wscale (&tc->rcv_opts))
292 opts->flags |= TCP_OPTS_FLAG_WSCALE;
293 opts->wscale = tc->rcv_wscale;
294 len += TCP_OPTION_LEN_WINDOW_SCALE;
297 if (tcp_opts_tstamp (&tc->rcv_opts))
299 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
300 opts->tsval = tcp_time_now ();
301 opts->tsecr = tc->tsval_recent;
302 len += TCP_OPTION_LEN_TIMESTAMP;
305 if (tcp_opts_sack_permitted (&tc->rcv_opts))
307 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
308 len += TCP_OPTION_LEN_SACK_PERMITTED;
311 /* Align to needed boundary */
312 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
317 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
323 if (tcp_opts_tstamp (&tc->rcv_opts))
325 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
326 opts->tsval = tcp_tstamp (tc);
327 opts->tsecr = tc->tsval_recent;
328 len += TCP_OPTION_LEN_TIMESTAMP;
330 if (tcp_opts_sack_permitted (&tc->rcv_opts))
332 if (vec_len (tc->snd_sacks))
334 opts->flags |= TCP_OPTS_FLAG_SACK;
335 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
336 tc->snd_sack_pos = 0;
337 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
338 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
339 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
340 TCP_OPTS_MAX_SACK_BLOCKS);
341 tc->snd_sack_pos += opts->n_sack_blocks;
342 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
346 /* Align to needed boundary */
347 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
352 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
357 case TCP_STATE_ESTABLISHED:
358 case TCP_STATE_CLOSE_WAIT:
359 case TCP_STATE_FIN_WAIT_1:
360 case TCP_STATE_LAST_ACK:
361 case TCP_STATE_CLOSING:
362 case TCP_STATE_FIN_WAIT_2:
363 case TCP_STATE_TIME_WAIT:
364 case TCP_STATE_CLOSED:
365 return tcp_make_established_options (tc, opts);
366 case TCP_STATE_SYN_RCVD:
367 return tcp_make_synack_options (tc, opts);
368 case TCP_STATE_SYN_SENT:
369 return tcp_make_syn_options (tc, opts);
371 clib_warning ("State not handled! %d", state);
377 * Update burst send vars
379 * - Updates snd_mss to reflect the effective segment size that we can send
380 * by taking into account all TCP options, including SACKs.
381 * - Cache 'on the wire' options for reuse
382 * - Updates receive window which can be reused for a burst.
384 * This should *only* be called when doing bursts
387 tcp_update_burst_snd_vars (tcp_connection_t * tc)
389 tcp_main_t *tm = &tcp_main;
391 /* Compute options to be used for connection. These may be reused when
392 * sending data or to compute the effective mss (snd_mss) */
393 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
394 TCP_STATE_ESTABLISHED);
396 /* XXX check if MTU has been updated */
397 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
398 ASSERT (tc->snd_mss > 0);
400 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
403 tcp_update_rcv_wnd (tc);
405 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
406 tcp_bt_check_app_limited (tc);
408 if (tc->snd_una == tc->snd_nxt)
410 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
411 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_MSS);
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);
448 /* Compute TCP checksum in software when offloading is disabled for a connection */
450 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
451 ip46_address_t * src, ip46_address_t * dst)
454 u16 payload_length_host_byte_order;
457 /* Initialize checksum with ip header. */
458 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
459 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
460 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
462 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
464 sum0 = ip_csum_with_carry
465 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
466 sum0 = ip_csum_with_carry
467 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
470 return ip_calculate_l4_checksum (vm, p0, sum0,
471 payload_length_host_byte_order, NULL, 0,
476 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
477 ip46_address_t * src, ip46_address_t * dst)
480 u32 payload_length_host_byte_order;
482 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
484 clib_host_to_net_u32 (payload_length_host_byte_order +
485 (IP_PROTOCOL_TCP << 16));
487 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
488 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
490 return ip_calculate_l4_checksum (vm, p0, sum0,
491 payload_length_host_byte_order, NULL, 0,
496 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
499 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
501 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
502 vlib_main_t *vm = wrk->vm;
505 checksum = ip4_tcp_compute_checksum_custom
506 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
508 checksum = ip6_tcp_compute_checksum_custom
509 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
513 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
522 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
525 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
526 u8 tcp_opts_len, tcp_hdr_opts_len;
530 wnd = tcp_window_to_advertise (tc, state);
532 /* Make and write options */
533 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
534 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
536 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
537 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
539 tcp_options_write ((u8 *) (th + 1), snd_opts);
541 th->checksum = tcp_compute_checksum (tc, b);
543 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
546 tcp_zero_rwnd_sent_on (tc);
548 tcp_zero_rwnd_sent_off (tc);
552 * Convert buffer to ACK
555 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
557 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
558 TCP_EVT (TCP_EVT_ACK_SENT, tc);
559 tc->rcv_las = tc->rcv_nxt;
563 * Convert buffer to FIN-ACK
566 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
568 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
572 * Convert buffer to SYN
575 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
577 u8 tcp_hdr_opts_len, tcp_opts_len;
580 tcp_options_t snd_opts;
582 initial_wnd = tcp_initial_window_to_advertise (tc);
584 /* Make and write options */
585 clib_memset (&snd_opts, 0, sizeof (snd_opts));
586 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
587 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
589 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
590 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
592 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
593 tcp_options_write ((u8 *) (th + 1), &snd_opts);
594 th->checksum = tcp_compute_checksum (tc, b);
598 * Convert buffer to SYN-ACK
601 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
603 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
604 u8 tcp_opts_len, tcp_hdr_opts_len;
608 clib_memset (snd_opts, 0, sizeof (*snd_opts));
609 initial_wnd = tcp_initial_window_to_advertise (tc);
610 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
611 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
613 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
614 tc->rcv_nxt, tcp_hdr_opts_len,
615 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
616 tcp_options_write ((u8 *) (th + 1), snd_opts);
618 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
619 th->checksum = tcp_compute_checksum (tc, b);
623 tcp_enqueue_to_ip_lookup_i (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
624 u8 is_ip4, u32 fib_index, u8 flush)
626 vlib_main_t *vm = wrk->vm;
627 u32 *to_next, next_index;
630 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
633 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
634 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
636 /* Send to IP lookup */
637 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
638 tcp_trajectory_add_start (b, 1);
640 f = wrk->ip_lookup_tx_frames[!is_ip4];
643 f = vlib_get_frame_to_node (vm, next_index);
645 wrk->ip_lookup_tx_frames[!is_ip4] = f;
648 to_next = vlib_frame_vector_args (f);
649 to_next[f->n_vectors] = bi;
651 if (flush || f->n_vectors == VLIB_FRAME_SIZE)
653 vlib_put_frame_to_node (vm, next_index, f);
654 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
659 tcp_enqueue_to_ip_lookup_now (tcp_worker_ctx_t * wrk, vlib_buffer_t * b,
660 u32 bi, u8 is_ip4, u32 fib_index)
662 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 1);
666 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
667 u8 is_ip4, u32 fib_index)
669 tcp_enqueue_to_ip_lookup_i (wrk, b, bi, is_ip4, fib_index, 0);
670 if (wrk->vm->thread_index == 0 && vlib_num_workers ())
671 session_flush_frames_main_thread (wrk->vm);
675 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
680 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
683 st = session_type_from_proto_and_ip (TRANSPORT_PROTO_TCP, is_ip4);
684 session_add_pending_tx_buffer (st, wrk->vm->thread_index, bi);
687 #endif /* CLIB_MARCH_VARIANT */
690 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
691 tcp_state_t state, u8 thread_index, u8 is_ip4)
696 ip4_address_t src_ip40, dst_ip40;
697 ip6_address_t src_ip60, dst_ip60;
698 u16 src_port, dst_port;
703 /* Find IP and TCP headers */
704 th0 = tcp_buffer_hdr (b0);
706 /* Save src and dst ip */
709 ih4 = vlib_buffer_get_current (b0);
710 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
711 src_ip40.as_u32 = ih4->src_address.as_u32;
712 dst_ip40.as_u32 = ih4->dst_address.as_u32;
716 ih6 = vlib_buffer_get_current (b0);
717 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
718 clib_memcpy_fast (&src_ip60, &ih6->src_address, sizeof (ip6_address_t));
719 clib_memcpy_fast (&dst_ip60, &ih6->dst_address, sizeof (ip6_address_t));
722 src_port = th0->src_port;
723 dst_port = th0->dst_port;
725 /* Try to determine what/why we're actually resetting */
726 if (state == TCP_STATE_CLOSED)
731 tmp = clib_net_to_host_u32 (th0->seq_number);
733 /* Got a SYN for no listener. */
734 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
735 ack = clib_host_to_net_u32 (tmp + 1);
740 flags = TCP_FLAG_RST;
741 seq = th0->ack_number;
745 tcp_reuse_buffer (vm, b0);
746 tcp_trajectory_add_start (b0, 4);
747 th0 = vlib_buffer_push_tcp_net_order (b0, dst_port, src_port, seq, ack,
748 sizeof (tcp_header_t), flags, 0);
752 ih4 = vlib_buffer_push_ip4 (vm, b0, &dst_ip40, &src_ip40,
754 th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih4);
759 ih6 = vlib_buffer_push_ip6 (vm, b0, &dst_ip60, &src_ip60,
761 th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih6, &bogus);
768 #ifndef CLIB_MARCH_VARIANT
770 * Send reset without reusing existing buffer
772 * It extracts connection info out of original packet
775 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
776 u32 thread_index, u8 is_ip4)
778 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
779 vlib_main_t *vm = wrk->vm;
781 u32 bi, sw_if_index, fib_index;
782 u8 tcp_hdr_len, flags = 0;
783 tcp_header_t *th, *pkt_th;
785 ip4_header_t *ih4, *pkt_ih4;
786 ip6_header_t *ih6, *pkt_ih6;
787 fib_protocol_t fib_proto;
789 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
792 b = vlib_get_buffer (vm, bi);
793 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
794 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
795 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
796 tcp_init_buffer (vm, b);
798 /* Make and write options */
799 tcp_hdr_len = sizeof (tcp_header_t);
803 pkt_ih4 = vlib_buffer_get_current (pkt);
804 pkt_th = ip4_next_header (pkt_ih4);
808 pkt_ih6 = vlib_buffer_get_current (pkt);
809 pkt_th = ip6_next_header (pkt_ih6);
812 if (tcp_ack (pkt_th))
814 flags = TCP_FLAG_RST;
815 seq = pkt_th->ack_number;
816 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
820 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
822 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
825 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
826 seq, ack, tcp_hdr_len, flags, 0);
828 /* Swap src and dst ip */
831 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
832 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
833 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
834 tcp_csum_offload (tc));
835 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
840 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
842 ih6 = vlib_buffer_push_ip6 (vm, b, &pkt_ih6->dst_address,
843 &pkt_ih6->src_address, IP_PROTOCOL_TCP);
844 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
848 tcp_enqueue_to_ip_lookup_now (wrk, b, bi, is_ip4, fib_index);
849 TCP_EVT (TCP_EVT_RST_SENT, tc);
850 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
851 TCP_ERROR_RST_SENT, 1);
855 * Build and set reset packet for connection
858 tcp_send_reset (tcp_connection_t * tc)
860 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
861 vlib_main_t *vm = wrk->vm;
865 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
868 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
870 b = vlib_get_buffer (vm, bi);
871 tcp_init_buffer (vm, b);
873 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
874 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
875 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
876 flags = TCP_FLAG_RST;
877 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
878 tc->rcv_nxt, tcp_hdr_opts_len, flags,
880 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
881 th->checksum = tcp_compute_checksum (tc, b);
882 ASSERT (opts_write_len == tc->snd_opts_len);
883 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
884 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
885 TCP_EVT (TCP_EVT_RST_SENT, tc);
886 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
887 TCP_ERROR_RST_SENT, 1);
891 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
894 tcp_header_t *th = vlib_buffer_get_current (b);
895 vlib_main_t *vm = wrk->vm;
899 ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
900 &tc->c_rmt_ip4, IP_PROTOCOL_TCP,
901 tcp_csum_offload (tc));
902 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
909 ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
910 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
911 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
919 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
920 * The packet is not forwarded through tcpx_output to avoid doing lookups
921 * in the half_open pool.
924 tcp_send_syn (tcp_connection_t * tc)
926 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
927 vlib_main_t *vm = wrk->vm;
932 * Setup retransmit and establish timers before requesting buffer
933 * such that we can return if we've ran out.
935 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
936 tc->rto * TCP_TO_TIMER_TICK);
938 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
940 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
944 b = vlib_get_buffer (vm, bi);
945 tcp_init_buffer (vm, b);
946 tcp_make_syn (tc, b);
948 /* Measure RTT with this */
949 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
950 tc->rtt_seq = tc->snd_nxt;
953 tcp_push_ip_hdr (wrk, tc, b);
954 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
955 TCP_EVT (TCP_EVT_SYN_SENT, tc);
959 tcp_send_synack (tcp_connection_t * tc)
961 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
962 vlib_main_t *vm = wrk->vm;
966 tcp_retransmit_timer_force_update (tc);
968 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
970 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
974 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
975 b = vlib_get_buffer (vm, bi);
976 tcp_init_buffer (vm, b);
977 tcp_make_synack (tc, b);
978 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
979 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
983 * Flush ip lookup tx frames populated by timer pops
986 tcp_flush_frame_to_ip_lookup (tcp_worker_ctx_t * wrk, u8 is_ip4)
988 if (wrk->ip_lookup_tx_frames[!is_ip4])
991 next_index = is_ip4 ? ip4_lookup_node.index : ip6_lookup_node.index;
992 vlib_put_frame_to_node (wrk->vm, next_index,
993 wrk->ip_lookup_tx_frames[!is_ip4]);
994 wrk->ip_lookup_tx_frames[!is_ip4] = 0;
999 * Flush v4 and v6 tcp and ip-lookup tx frames for thread index
1002 tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk)
1004 tcp_flush_frame_to_ip_lookup (wrk, 1);
1005 tcp_flush_frame_to_ip_lookup (wrk, 0);
1012 tcp_send_fin (tcp_connection_t * tc)
1014 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1015 vlib_main_t *vm = wrk->vm;
1020 fin_snt = tc->flags & TCP_CONN_FINSNT;
1024 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1026 /* Out of buffers so program fin retransmit ASAP */
1027 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1031 /* Make sure retransmit retries a fin not data */
1032 tc->flags |= TCP_CONN_FINSNT;
1036 /* If we have non-dupacks programmed, no need to send them */
1037 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
1038 tc->flags &= ~TCP_CONN_SNDACK;
1040 tcp_retransmit_timer_force_update (tc);
1041 b = vlib_get_buffer (vm, bi);
1042 tcp_init_buffer (vm, b);
1043 tcp_make_fin (tc, b);
1044 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1045 TCP_EVT (TCP_EVT_FIN_SENT, tc);
1046 /* Account for the FIN */
1050 tc->flags |= TCP_CONN_FINSNT;
1051 tc->flags &= ~TCP_CONN_FINPNDG;
1052 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
1057 * Push TCP header and update connection variables. Should only be called
1058 * for segments with data, not for 'control' packets.
1061 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
1062 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
1064 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
1065 u32 advertise_wnd, data_len;
1066 tcp_main_t *tm = &tcp_main;
1069 data_len = b->current_length;
1070 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1071 data_len += b->total_length_not_including_first_buffer;
1073 vnet_buffer (b)->tcp.flags = 0;
1074 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
1077 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1079 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
1082 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
1084 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
1086 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
1088 if (seq_geq (tc->psh_seq, snd_nxt)
1089 && seq_lt (tc->psh_seq, snd_nxt + data_len))
1090 flags |= TCP_FLAG_PSH;
1092 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
1093 tc->rcv_nxt, tcp_hdr_opts_len, flags,
1098 clib_memcpy_fast ((u8 *) (th + 1),
1099 tm->wrk_ctx[tc->c_thread_index].cached_opts,
1104 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
1105 ASSERT (len == tc->snd_opts_len);
1109 * Update connection variables
1113 tc->snd_nxt += data_len;
1114 tc->rcv_las = tc->rcv_nxt;
1116 tc->bytes_out += data_len;
1117 tc->data_segs_out += 1;
1119 th->checksum = tcp_compute_checksum (tc, b);
1121 TCP_EVT (TCP_EVT_PKTIZE, tc);
1125 tcp_buffer_len (vlib_buffer_t * b)
1127 u32 data_len = b->current_length;
1128 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
1129 data_len += b->total_length_not_including_first_buffer;
1134 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
1136 tcp_connection_t *tc = (tcp_connection_t *) tconn;
1138 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1139 tcp_bt_track_tx (tc, tcp_buffer_len (b));
1141 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
1142 /* update_snd_nxt */ 1);
1144 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1145 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1146 /* If not tracking an ACK, start tracking */
1147 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
1149 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
1150 tc->rtt_seq = tc->snd_nxt;
1152 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1154 tcp_retransmit_timer_set (tc);
1157 tcp_trajectory_add_start (b, 3);
1162 tcp_send_ack (tcp_connection_t * tc)
1164 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1165 vlib_main_t *vm = wrk->vm;
1169 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1171 tcp_update_rcv_wnd (tc);
1174 b = vlib_get_buffer (vm, bi);
1175 tcp_init_buffer (vm, b);
1176 tcp_make_ack (tc, b);
1177 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1181 tcp_program_ack (tcp_connection_t * tc)
1183 if (!(tc->flags & TCP_CONN_SNDACK))
1185 session_add_self_custom_tx_evt (&tc->connection, 1);
1186 tc->flags |= TCP_CONN_SNDACK;
1191 tcp_program_dupack (tcp_connection_t * tc)
1193 if (!(tc->flags & TCP_CONN_SNDACK))
1195 session_add_self_custom_tx_evt (&tc->connection, 1);
1196 tc->flags |= TCP_CONN_SNDACK;
1198 if (tc->pending_dupacks < 255)
1199 tc->pending_dupacks += 1;
1203 tcp_program_retransmit (tcp_connection_t * tc)
1205 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1207 session_add_self_custom_tx_evt (&tc->connection, 0);
1208 tc->flags |= TCP_CONN_RXT_PENDING;
1213 * Delayed ack timer handler
1215 * Sends delayed ACK when timer expires
1218 tcp_timer_delack_handler (u32 index, u32 thread_index)
1220 tcp_connection_t *tc;
1222 tc = tcp_connection_get (index, thread_index);
1227 * Send window update ack
1229 * Ensures that it will be sent only once, after a zero rwnd has been
1230 * advertised in a previous ack, and only if rwnd has grown beyond a
1231 * configurable value.
1234 tcp_send_window_update_ack (tcp_connection_t * tc)
1236 if (tcp_zero_rwnd_sent (tc))
1238 tcp_update_rcv_wnd (tc);
1239 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1241 tcp_zero_rwnd_sent_off (tc);
1242 tcp_program_ack (tc);
1248 * Allocate a new buffer and build a new tcp segment
1250 * @param wrk tcp worker
1251 * @param tc connection for which the segment will be allocated
1252 * @param offset offset of the first byte in the tx fifo
1253 * @param max_deq_byte segment size
1254 * @param[out] b pointer to buffer allocated
1256 * @return the number of bytes in the segment or 0 if buffer cannot be
1257 * allocated or no data available
1260 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1261 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1263 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1264 vlib_main_t *vm = wrk->vm;
1269 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1274 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1277 * Allocate and fill in buffer(s)
1280 /* Easy case, buffer size greater than mss */
1281 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1283 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1285 *b = vlib_get_buffer (vm, bi);
1286 data = tcp_init_buffer (vm, *b);
1287 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1289 ASSERT (n_bytes == max_deq_bytes);
1290 b[0]->current_length = n_bytes;
1291 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1292 /* burst */ 0, /* update_snd_nxt */ 0);
1294 /* Split mss into multiple buffers */
1297 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1298 u16 n_peeked, len_to_deq;
1299 vlib_buffer_t *chain_b, *prev_b;
1302 /* Make sure we have enough buffers */
1303 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1304 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1305 CLIB_CACHE_LINE_BYTES);
1306 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1307 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1310 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1314 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1315 data = tcp_init_buffer (vm, *b);
1316 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1318 TRANSPORT_MAX_HDRS_LEN);
1319 b[0]->current_length = n_bytes;
1320 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1321 b[0]->total_length_not_including_first_buffer = 0;
1322 max_deq_bytes -= n_bytes;
1325 for (i = 1; i < n_bufs_per_seg; i++)
1328 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1329 chain_bi = wrk->tx_buffers[--n_bufs];
1330 chain_b = vlib_get_buffer (vm, chain_bi);
1331 chain_b->current_data = 0;
1332 data = vlib_buffer_get_current (chain_b);
1333 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1336 ASSERT (n_peeked == len_to_deq);
1337 n_bytes += n_peeked;
1338 chain_b->current_length = n_peeked;
1339 chain_b->next_buffer = 0;
1341 /* update previous buffer */
1342 prev_b->next_buffer = chain_bi;
1343 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1345 max_deq_bytes -= n_peeked;
1346 b[0]->total_length_not_including_first_buffer += n_peeked;
1349 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1350 /* burst */ 0, /* update_snd_nxt */ 0);
1352 if (PREDICT_FALSE (n_bufs))
1354 clib_warning ("not all buffers consumed");
1355 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1359 ASSERT (n_bytes > 0);
1360 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1366 * Build a retransmit segment
1368 * @return the number of bytes in the segment or 0 if there's nothing to
1372 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1373 tcp_connection_t * tc, u32 offset,
1374 u32 max_deq_bytes, vlib_buffer_t ** b)
1376 u32 start, available_bytes;
1379 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1380 ASSERT (max_deq_bytes != 0);
1383 * Make sure we can retransmit something
1385 available_bytes = transport_max_tx_dequeue (&tc->connection);
1386 ASSERT (available_bytes >= offset);
1387 available_bytes -= offset;
1388 if (!available_bytes)
1391 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1392 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1394 start = tc->snd_una + offset;
1395 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1397 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1401 tc->snd_rxt_bytes += n_bytes;
1403 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1404 tcp_bt_track_rxt (tc, start, start + n_bytes);
1406 tc->bytes_retrans += n_bytes;
1407 tc->segs_retrans += 1;
1408 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1414 tcp_check_sack_reneging (tcp_connection_t * tc)
1416 sack_scoreboard_t *sb = &tc->sack_sb;
1417 sack_scoreboard_hole_t *hole;
1419 hole = scoreboard_first_hole (sb);
1420 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1423 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1427 * Reset congestion control, switch cwnd to loss window and try again.
1430 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1432 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1434 tc->prev_ssthresh = tc->ssthresh;
1435 tc->prev_cwnd = tc->cwnd;
1437 /* If we entrered loss without fast recovery, notify cc algo of the
1438 * congestion event such that it can update ssthresh and its state */
1439 if (!tcp_in_fastrecovery (tc))
1440 tcp_cc_congestion (tc);
1442 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1446 tc->cwnd_acc_bytes = 0;
1447 tc->tr_occurences += 1;
1448 tcp_recovery_on (tc);
1452 tcp_timer_retransmit_handler (u32 tc_index, u32 thread_index)
1454 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1455 vlib_main_t *vm = wrk->vm;
1456 tcp_connection_t *tc;
1457 vlib_buffer_t *b = 0;
1460 tc = tcp_connection_get (tc_index, thread_index);
1462 /* Note: the connection may have been closed and pool_put */
1463 if (PREDICT_FALSE (tc == 0 || tc->state == TCP_STATE_SYN_SENT))
1466 /* Wait-close and retransmit could pop at the same time */
1467 if (tc->state == TCP_STATE_CLOSED)
1470 if (tc->state >= TCP_STATE_ESTABLISHED)
1472 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1474 /* Lost FIN, retransmit and return */
1475 if (tc->flags & TCP_CONN_FINSNT)
1479 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1483 /* Shouldn't be here. This condition is tricky because it has to take
1484 * into account boff > 0 due to persist timeout. */
1485 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1486 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1487 && !tcp_flight_size (tc)))
1489 ASSERT (!tcp_in_recovery (tc));
1494 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1495 * to persist timer timeout */
1496 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1499 tcp_update_rto (tc);
1502 /* Peer is dead or network connectivity is lost. Close connection.
1503 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1504 * a min rto of 0.2s we need to retry about 8 times. */
1505 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1507 tcp_send_reset (tc);
1508 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1509 session_transport_closing_notify (&tc->connection);
1510 session_transport_closed_notify (&tc->connection);
1511 tcp_connection_timers_reset (tc);
1512 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.closewait_time);
1516 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1517 tcp_check_sack_reneging (tc);
1519 /* Update send congestion to make sure that rxt has data to send */
1520 tc->snd_congestion = tc->snd_nxt;
1522 /* Send the first unacked segment. If we're short on buffers, return
1523 * as soon as possible */
1524 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1525 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1528 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1532 bi = vlib_get_buffer_index (vm, b);
1533 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1535 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1536 tcp_retransmit_timer_force_update (tc);
1539 if (tc->rto_boff == 1)
1541 tcp_cc_init_rxt_timeout (tc);
1542 /* Record timestamp. Eifel detection algorithm RFC3522 */
1543 tc->snd_rxt_ts = tcp_tstamp (tc);
1546 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1547 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1549 tcp_program_retransmit (tc);
1551 /* Retransmit SYN-ACK */
1552 else if (tc->state == TCP_STATE_SYN_RCVD)
1554 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1558 /* Passive open establish timeout */
1559 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1561 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1562 tcp_connection_timers_reset (tc);
1563 tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, tcp_cfg.cleanup_time);
1567 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1569 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1);
1574 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1575 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1577 tcp_retransmit_timer_force_update (tc);
1579 b = vlib_get_buffer (vm, bi);
1580 tcp_init_buffer (vm, b);
1581 tcp_make_synack (tc, b);
1582 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1584 /* Retransmit timer already updated, just enqueue to output */
1585 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1589 ASSERT (tc->state == TCP_STATE_CLOSED);
1595 * SYN retransmit timer handler. Active open only.
1598 tcp_timer_retransmit_syn_handler (u32 tc_index, u32 thread_index)
1600 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1601 vlib_main_t *vm = wrk->vm;
1602 tcp_connection_t *tc;
1603 vlib_buffer_t *b = 0;
1606 tc = tcp_half_open_connection_get (tc_index);
1608 /* Note: the connection may have transitioned to ESTABLISHED... */
1609 if (PREDICT_FALSE (tc == 0 || tc->state != TCP_STATE_SYN_SENT))
1612 /* Half-open connection actually moved to established but we were
1613 * waiting for syn retransmit to pop to call cleanup from the right
1615 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1617 if (tcp_half_open_connection_cleanup (tc))
1618 TCP_DBG ("could not remove half-open connection");
1622 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1625 /* Active open establish timeout */
1626 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1628 session_stream_connect_notify (&tc->connection, 1 /* fail */ );
1629 tcp_connection_cleanup (tc);
1633 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1635 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1639 /* Try without increasing RTO a number of times. If this fails,
1640 * start growing RTO exponentially */
1642 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1643 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1645 b = vlib_get_buffer (vm, bi);
1646 tcp_init_buffer (vm, b);
1647 tcp_make_syn (tc, b);
1649 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1651 /* This goes straight to ipx_lookup */
1652 tcp_push_ip_hdr (wrk, tc, b);
1653 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1655 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT_SYN,
1656 tc->rto * TCP_TO_TIMER_TICK);
1660 * Got 0 snd_wnd from peer, try to do something about it.
1664 tcp_timer_persist_handler (u32 index, u32 thread_index)
1666 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
1667 u32 bi, max_snd_bytes, available_bytes, offset;
1668 tcp_main_t *tm = vnet_get_tcp_main ();
1669 vlib_main_t *vm = wrk->vm;
1670 tcp_connection_t *tc;
1675 tc = tcp_connection_get_if_valid (index, thread_index);
1679 /* Problem already solved or worse */
1680 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1681 || (tc->flags & TCP_CONN_FINSNT))
1684 available_bytes = transport_max_tx_dequeue (&tc->connection);
1685 offset = tc->snd_nxt - tc->snd_una;
1687 /* Reprogram persist if no new bytes available to send. We may have data
1689 if (!available_bytes)
1691 tcp_persist_timer_set (tc);
1695 if (available_bytes <= offset)
1698 /* Increment RTO backoff */
1700 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1703 * Try to force the first unsent segment (or buffer)
1705 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1707 tcp_persist_timer_set (tc);
1710 b = vlib_get_buffer (vm, bi);
1711 data = tcp_init_buffer (vm, b);
1713 tcp_validate_txf_size (tc, offset);
1714 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1715 max_snd_bytes = clib_min (tc->snd_mss,
1716 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1717 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1719 b->current_length = n_bytes;
1720 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1721 || tc->snd_nxt == tc->snd_una_max
1722 || tc->rto_boff > 1));
1724 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1726 tcp_bt_check_app_limited (tc);
1727 tcp_bt_track_tx (tc, n_bytes);
1730 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1731 /* burst */ 0, /* update_snd_nxt */ 1);
1732 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1733 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1734 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1736 /* Just sent new data, enable retransmit */
1737 tcp_retransmit_timer_update (tc);
1741 * Retransmit first unacked segment
1744 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1746 vlib_main_t *vm = wrk->vm;
1750 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1752 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1756 bi = vlib_get_buffer_index (vm, b);
1757 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1763 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1766 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1767 vlib_main_t *vm = wrk->vm;
1768 vlib_buffer_t *b = 0;
1770 offset = tc->snd_nxt - tc->snd_una;
1771 available_wnd = tc->snd_wnd - offset;
1772 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1774 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1775 tcp_bt_check_app_limited (tc);
1777 while (n_segs < burst_size)
1779 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1783 bi = vlib_get_buffer_index (vm, b);
1784 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1785 offset += n_written;
1788 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1789 tcp_bt_track_tx (tc, n_written);
1791 tc->snd_nxt += n_written;
1792 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1800 * Estimate send space using proportional rate reduction (RFC6937)
1803 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1808 pipe = tcp_flight_size (tc);
1809 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1811 if (pipe > tc->ssthresh)
1813 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1819 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1820 space = clib_min (tc->ssthresh - pipe, limit);
1822 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1827 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1828 sack_scoreboard_t * sb)
1830 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1831 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1833 if (tcp_fastrecovery_first (tc))
1836 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1840 tcp_max_tx_deq (tcp_connection_t * tc)
1842 return (transport_max_tx_dequeue (&tc->connection)
1843 - (tc->snd_nxt - tc->snd_una));
1846 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1847 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1848 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1851 * Do retransmit with SACKs
1854 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1857 u8 snd_limited = 0, can_rescue = 0, reset_pacer = 0;
1858 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1859 u32 bi, max_deq, burst_bytes, sent_bytes;
1860 sack_scoreboard_hole_t *hole;
1861 vlib_main_t *vm = wrk->vm;
1862 vlib_buffer_t *b = 0;
1863 sack_scoreboard_t *sb;
1866 ASSERT (tcp_in_cong_recovery (tc));
1868 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1869 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1872 tcp_program_retransmit (tc);
1876 if (tcp_in_recovery (tc))
1877 snd_space = tcp_available_cc_snd_space (tc);
1879 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1881 if (snd_space < tc->snd_mss)
1883 reset_pacer = burst_bytes > tc->snd_mss;
1887 reset_pacer = snd_space < burst_bytes;
1891 /* Check if snd_una is a lost retransmit */
1892 if (pool_elts (sb->holes)
1893 && seq_gt (sb->high_sacked, tc->snd_congestion)
1894 && tc->rxt_head != tc->snd_una
1895 && tcp_retransmit_should_retry_head (tc, sb))
1897 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1898 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1901 tcp_program_retransmit (tc);
1904 bi = vlib_get_buffer_index (vm, b);
1905 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1908 tc->rxt_head = tc->snd_una;
1909 tc->rxt_delivered += n_written;
1910 tc->prr_delivered += n_written;
1911 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1914 tcp_fastrecovery_first_off (tc);
1916 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1917 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1919 max_deq = transport_max_tx_dequeue (&tc->connection);
1920 max_deq -= tc->snd_nxt - tc->snd_una;
1922 while (snd_space > 0 && n_segs < burst_size)
1924 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1928 /* We are out of lost holes to retransmit so send some new data. */
1929 if (max_deq > tc->snd_mss)
1934 /* Make sure we don't exceed available window and leave space
1935 * for one more packet, to avoid zero window acks */
1936 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1937 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1938 snd_space = clib_min (snd_space, av_wnd);
1939 snd_space = clib_min (max_deq, snd_space);
1940 burst_size = clib_min (burst_size - n_segs,
1941 snd_space / tc->snd_mss);
1942 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1943 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1944 if (max_deq > n_segs_new * tc->snd_mss)
1945 tcp_program_retransmit (tc);
1947 n_segs += n_segs_new;
1951 if (tcp_in_recovery (tc) || !can_rescue
1952 || scoreboard_rescue_rxt_valid (sb, tc))
1955 /* If rescue rxt undefined or less than snd_una then one segment of
1956 * up to SMSS octets that MUST include the highest outstanding
1957 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1958 * RecoveryPoint. HighRxt MUST NOT be updated.
1960 hole = scoreboard_last_hole (sb);
1961 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1962 max_bytes = clib_min (max_bytes, snd_space);
1963 offset = hole->end - tc->snd_una - max_bytes;
1964 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1969 sb->rescue_rxt = tc->snd_congestion;
1970 bi = vlib_get_buffer_index (vm, b);
1971 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1976 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1977 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1981 offset = sb->high_rxt - tc->snd_una;
1982 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1984 ASSERT (n_written <= snd_space);
1986 /* Nothing left to retransmit */
1990 bi = vlib_get_buffer_index (vm, b);
1991 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1993 sb->high_rxt += n_written;
1994 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1996 snd_space -= n_written;
2001 tcp_program_retransmit (tc);
2007 transport_connection_tx_pacer_reset_bucket (&tc->connection);
2011 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2012 transport_connection_tx_pacer_update_bytes (&tc->connection,
2020 * Fast retransmit without SACK info
2023 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
2026 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
2027 u32 burst_bytes, sent_bytes;
2028 vlib_main_t *vm = wrk->vm;
2029 int snd_space, n_segs = 0;
2033 ASSERT (tcp_in_cong_recovery (tc));
2034 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
2036 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
2037 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
2040 tcp_program_retransmit (tc);
2044 snd_space = tcp_available_cc_snd_space (tc);
2045 cc_limited = snd_space < burst_bytes;
2047 if (!tcp_fastrecovery_first (tc))
2050 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
2052 while (snd_space > 0 && n_segs < burst_size)
2054 max_bytes = clib_min (tc->snd_mss,
2055 tc->snd_congestion - tc->snd_una - offset);
2058 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
2061 /* Nothing left to retransmit */
2065 bi = vlib_get_buffer_index (vm, b);
2066 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
2067 snd_space -= n_written;
2068 offset += n_written;
2072 if (n_segs == burst_size)
2077 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
2078 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
2081 max_deq = transport_max_tx_dequeue (&tc->connection);
2082 max_deq -= tc->snd_nxt - tc->snd_una;
2085 snd_space = clib_min (max_deq, snd_space);
2086 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
2087 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
2088 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
2089 tcp_program_retransmit (tc);
2090 n_segs += n_segs_now;
2094 tcp_fastrecovery_first_off (tc);
2096 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
2097 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
2098 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
2104 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
2108 if (!tc->pending_dupacks)
2110 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
2111 || tc->state != TCP_STATE_ESTABLISHED)
2119 /* If we're supposed to send dupacks but have no ooo data
2120 * send only one ack */
2121 if (!vec_len (tc->snd_sacks))
2124 tc->dupacks_out += 1;
2125 tc->pending_dupacks = 0;
2129 /* Start with first sack block */
2130 tc->snd_sack_pos = 0;
2132 /* Generate enough dupacks to cover all sack blocks. Do not generate
2133 * more sacks than the number of packets received. But do generate at
2134 * least 3, i.e., the number needed to signal congestion, if needed. */
2135 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
2136 n_acks = clib_min (n_acks, tc->pending_dupacks);
2137 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
2138 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
2141 if (n_acks < max_burst_size)
2143 tc->pending_dupacks = 0;
2144 tc->snd_sack_pos = 0;
2145 tc->dupacks_out += n_acks;
2150 TCP_DBG ("constrained by burst size");
2151 tc->pending_dupacks = n_acks - max_burst_size;
2152 tc->dupacks_out += max_burst_size;
2153 tcp_program_dupack (tc);
2154 return max_burst_size;
2159 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
2161 tcp_worker_ctx_t *wrk;
2164 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2167 wrk = tcp_get_worker (tc->c_thread_index);
2169 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2170 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2172 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2178 tcp_session_custom_tx (void *conn, u32 max_burst_size)
2180 tcp_connection_t *tc = (tcp_connection_t *) conn;
2183 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2185 tc->flags &= ~TCP_CONN_RXT_PENDING;
2186 n_segs = tcp_do_retransmit (tc, max_burst_size);
2187 max_burst_size -= n_segs;
2190 if (!(tc->flags & TCP_CONN_SNDACK))
2193 tc->flags &= ~TCP_CONN_SNDACK;
2195 /* We have retransmitted packets and no dupack */
2196 if (n_segs && !tc->pending_dupacks)
2199 if (!max_burst_size)
2201 tcp_program_ack (tc);
2202 return max_burst_size;
2205 n_segs += tcp_send_acks (tc, max_burst_size);
2209 #endif /* CLIB_MARCH_VARIANT */
2212 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2213 u16 * next0, u32 * error0)
2215 ip_adjacency_t *adj;
2218 /* Not thread safe but as long as the connection exists the adj should
2220 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2222 if (ai == ADJ_INDEX_INVALID)
2224 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2225 *next0 = TCP_OUTPUT_NEXT_DROP;
2226 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2231 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2232 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2233 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2234 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2237 *next0 = TCP_OUTPUT_NEXT_DROP;
2238 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2240 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2244 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2245 u32 * to_next, u32 n_bufs)
2247 tcp_connection_t *tc;
2253 for (i = 0; i < n_bufs; i++)
2255 b = vlib_get_buffer (vm, to_next[i]);
2256 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2258 th = vlib_buffer_get_current (b);
2259 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2261 t = vlib_add_trace (vm, node, b, sizeof (*t));
2262 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2263 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2268 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2269 tcp_connection_t * tc0, u8 is_ip4)
2271 u8 __clib_unused *ih0;
2272 tcp_header_t __clib_unused *th0 = vlib_buffer_get_current (b0);
2274 TCP_EVT (TCP_EVT_OUTPUT, tc0, th0->flags, b0->current_length);
2277 ih0 = vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2278 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2280 ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2286 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2288 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2291 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2293 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2294 data_len += b->total_length_not_including_first_buffer;
2296 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2300 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2301 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2302 b->flags |= VNET_BUFFER_F_GSO;
2303 vnet_buffer2 (b)->gso_l4_hdr_sz =
2304 sizeof (tcp_header_t) + tc->snd_opts_len;
2305 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2310 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2311 vlib_node_runtime_t * error_node, u16 * next0,
2314 /* If next_index is not drop use it */
2315 if (tc0->next_node_index)
2317 *next0 = tc0->next_node_index;
2318 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2322 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2325 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2326 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2332 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2333 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2335 if (PREDICT_FALSE (error0))
2337 b0->error = error_node->errors[error0];
2342 if (!TCP_ALWAYS_ACK)
2343 tcp_timer_reset (tc0, TCP_TIMER_DELACK);
2349 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2350 vlib_frame_t * frame, int is_ip4)
2352 u32 n_left_from, *from, thread_index = vm->thread_index;
2353 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2354 u16 nexts[VLIB_FRAME_SIZE], *next;
2355 vlib_node_runtime_t *error_node;
2357 error_node = vlib_node_get_runtime (vm, tcp_node_index (output, is_ip4));
2359 from = vlib_frame_vector_args (frame);
2360 n_left_from = frame->n_vectors;
2361 tcp_set_time_now (tcp_get_worker (thread_index));
2363 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2364 tcp46_output_trace_frame (vm, node, from, n_left_from);
2366 vlib_get_buffers (vm, from, bufs, n_left_from);
2370 while (n_left_from >= 4)
2372 tcp_connection_t *tc0, *tc1;
2375 vlib_prefetch_buffer_header (b[2], STORE);
2376 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2378 vlib_prefetch_buffer_header (b[3], STORE);
2379 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2382 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2384 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2387 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2389 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2390 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2392 tcp_check_if_gso (tc0, b[0]);
2393 tcp_check_if_gso (tc1, b[1]);
2395 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2396 tcp_output_handle_packet (tc1, b[1], error_node, &next[1], is_ip4);
2402 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2403 tcp_check_if_gso (tc0, b[0]);
2404 tcp_output_handle_packet (tc0, b[0], error_node, &next[0],
2409 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2410 next[0] = TCP_OUTPUT_NEXT_DROP;
2414 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2415 tcp_check_if_gso (tc1, b[1]);
2416 tcp_output_handle_packet (tc1, b[1], error_node, &next[1],
2421 b[1]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2422 next[1] = TCP_OUTPUT_NEXT_DROP;
2430 while (n_left_from > 0)
2432 tcp_connection_t *tc0;
2434 if (n_left_from > 1)
2436 vlib_prefetch_buffer_header (b[1], STORE);
2437 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2440 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2443 if (PREDICT_TRUE (tc0 != 0))
2445 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2446 tcp_check_if_gso (tc0, b[0]);
2447 tcp_output_handle_packet (tc0, b[0], error_node, &next[0], is_ip4);
2451 b[0]->error = error_node->errors[TCP_ERROR_INVALID_CONNECTION];
2452 next[0] = TCP_OUTPUT_NEXT_DROP;
2460 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2461 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2462 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2463 return frame->n_vectors;
2466 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2467 vlib_frame_t * from_frame)
2469 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2472 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2473 vlib_frame_t * from_frame)
2475 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2479 VLIB_REGISTER_NODE (tcp4_output_node) =
2481 .name = "tcp4-output",
2482 /* Takes a vector of packets. */
2483 .vector_size = sizeof (u32),
2484 .n_errors = TCP_N_ERROR,
2485 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2486 .error_strings = tcp_error_strings,
2487 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2489 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2490 foreach_tcp4_output_next
2493 .format_buffer = format_tcp_header,
2494 .format_trace = format_tcp_tx_trace,
2499 VLIB_REGISTER_NODE (tcp6_output_node) =
2501 .name = "tcp6-output",
2502 /* Takes a vector of packets. */
2503 .vector_size = sizeof (u32),
2504 .n_errors = TCP_N_ERROR,
2505 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2506 .error_strings = tcp_error_strings,
2507 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2509 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2510 foreach_tcp6_output_next
2513 .format_buffer = format_tcp_header,
2514 .format_trace = format_tcp_tx_trace,
2518 typedef enum _tcp_reset_next
2520 TCP_RESET_NEXT_DROP,
2521 TCP_RESET_NEXT_IP_LOOKUP,
2525 #define foreach_tcp4_reset_next \
2526 _(DROP, "error-drop") \
2527 _(IP_LOOKUP, "ip4-lookup")
2529 #define foreach_tcp6_reset_next \
2530 _(DROP, "error-drop") \
2531 _(IP_LOOKUP, "ip6-lookup")
2534 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2535 vlib_frame_t * from_frame, u8 is_ip4)
2537 u32 n_left_from, next_index, *from, *to_next;
2538 u32 my_thread_index = vm->thread_index;
2540 from = vlib_frame_vector_args (from_frame);
2541 n_left_from = from_frame->n_vectors;
2543 next_index = node->cached_next_index;
2545 while (n_left_from > 0)
2549 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2551 while (n_left_from > 0 && n_left_to_next > 0)
2557 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2564 n_left_to_next -= 1;
2566 b0 = vlib_get_buffer (vm, bi0);
2568 if (tcp_make_reset_in_place (vm, b0, vnet_buffer (b0)->tcp.flags,
2569 my_thread_index, is_ip4))
2571 error0 = TCP_ERROR_LOOKUP_DROPS;
2572 next0 = TCP_RESET_NEXT_DROP;
2576 /* Prepare to send to IP lookup */
2577 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2578 next0 = TCP_RESET_NEXT_IP_LOOKUP;
2581 b0->error = node->errors[error0];
2582 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2583 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2585 th0 = vlib_buffer_get_current (b0);
2587 th0 = ip4_next_header ((ip4_header_t *) th0);
2589 th0 = ip6_next_header ((ip6_header_t *) th0);
2590 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2591 clib_memcpy_fast (&t0->tcp_header, th0,
2592 sizeof (t0->tcp_header));
2595 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2596 n_left_to_next, bi0, next0);
2598 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2600 return from_frame->n_vectors;
2603 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2604 vlib_frame_t * from_frame)
2606 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2609 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2610 vlib_frame_t * from_frame)
2612 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2616 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2617 .name = "tcp4-reset",
2618 .vector_size = sizeof (u32),
2619 .n_errors = TCP_N_ERROR,
2620 .error_strings = tcp_error_strings,
2621 .n_next_nodes = TCP_RESET_N_NEXT,
2623 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2624 foreach_tcp4_reset_next
2627 .format_trace = format_tcp_tx_trace,
2632 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2633 .name = "tcp6-reset",
2634 .vector_size = sizeof (u32),
2635 .n_errors = TCP_N_ERROR,
2636 .error_strings = tcp_error_strings,
2637 .n_next_nodes = TCP_RESET_N_NEXT,
2639 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2640 foreach_tcp6_reset_next
2643 .format_trace = format_tcp_tx_trace,
2648 * fd.io coding-style-patch-verification: ON
2651 * eval: (c-set-style "gnu")