2 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vnet/tcp/tcp.h>
17 #include <vnet/tcp/tcp_inlines.h>
19 #include <vnet/ip/ip4_inlines.h>
20 #include <vnet/ip/ip6_inlines.h>
22 typedef enum _tcp_output_next
25 TCP_OUTPUT_NEXT_IP_LOOKUP,
26 TCP_OUTPUT_NEXT_IP_REWRITE,
27 TCP_OUTPUT_NEXT_IP_ARP,
31 #define foreach_tcp4_output_next \
32 _ (DROP, "error-drop") \
33 _ (IP_LOOKUP, "ip4-lookup") \
34 _ (IP_REWRITE, "ip4-rewrite") \
37 #define foreach_tcp6_output_next \
38 _ (DROP, "error-drop") \
39 _ (IP_LOOKUP, "ip6-lookup") \
40 _ (IP_REWRITE, "ip6-rewrite") \
41 _ (IP_ARP, "ip6-discover-neighbor")
43 static vlib_error_desc_t tcp_output_error_counters[] = {
44 #define tcp_error(f, n, s, d) { #n, d, VL_COUNTER_SEVERITY_##s },
45 #include <vnet/tcp/tcp_error.def>
51 tcp_header_t tcp_header;
52 tcp_connection_t tcp_connection;
56 format_tcp_tx_trace (u8 * s, va_list * args)
58 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
59 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
60 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
61 tcp_connection_t *tc = &t->tcp_connection;
62 u32 indent = format_get_indent (s);
64 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
65 format_tcp_state, tc->state, format_white_space, indent,
66 format_tcp_header, &t->tcp_header, 128);
71 #ifndef CLIB_MARCH_VARIANT
73 tcp_window_compute_scale (u32 window)
76 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
82 * TCP's initial window
85 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
87 /* RFC 6928 recommends the value lower. However at the time our connections
88 * are initialized, fifos may not be allocated. Therefore, advertise the
89 * smallest possible unscaled window size and update once fifos are
90 * assigned to the session.
93 tcp_update_rcv_mss (tc);
94 TCP_IW_N_SEGMENTS * tc->mss;
96 return tcp_cfg.min_rx_fifo;
100 * Compute initial window and scale factor. As per RFC1323, window field in
101 * SYN and SYN-ACK segments is never scaled.
104 tcp_initial_window_to_advertise (tcp_connection_t * tc)
106 /* Compute rcv wscale only if peer advertised support for it */
107 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
108 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
110 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
112 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
116 tcp_update_rcv_wnd (tcp_connection_t * tc)
118 u32 available_space, wnd;
122 * Figure out how much space we have available
124 available_space = transport_max_rx_enqueue (&tc->connection);
127 * Use the above and what we know about what we've previously advertised
128 * to compute the new window
130 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
132 /* Check if we are about to retract the window. Do the comparison before
133 * rounding to avoid errors. Per RFC7323 sec. 2.4 we could remove this */
134 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
136 wnd = round_down_pow2 (clib_max (observed_wnd, 0), 1 << tc->rcv_wscale);
137 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
141 /* Make sure we have a multiple of 1 << rcv_wscale. We round down to
142 * avoid advertising a window larger than what can be buffered */
143 wnd = round_down_pow2 (available_space, 1 << tc->rcv_wscale);
146 if (PREDICT_FALSE (wnd < tc->rcv_opts.mss))
149 tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
153 * Compute and return window to advertise, scaled as per RFC1323
156 tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
158 if (state < TCP_STATE_ESTABLISHED)
159 return tcp_initial_window_to_advertise (tc);
161 tcp_update_rcv_wnd (tc);
162 return tc->rcv_wnd >> tc->rcv_wscale;
166 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
170 opts->flags |= TCP_OPTS_FLAG_MSS;
172 len += TCP_OPTION_LEN_MSS;
174 opts->flags |= TCP_OPTS_FLAG_WSCALE;
175 opts->wscale = tc->rcv_wscale;
176 len += TCP_OPTION_LEN_WINDOW_SCALE;
178 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
179 opts->tsval = tcp_time_tstamp (tc->c_thread_index);
181 len += TCP_OPTION_LEN_TIMESTAMP;
185 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
186 len += TCP_OPTION_LEN_SACK_PERMITTED;
189 /* Align to needed boundary */
190 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
195 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
199 opts->flags |= TCP_OPTS_FLAG_MSS;
201 len += TCP_OPTION_LEN_MSS;
203 if (tcp_opts_wscale (&tc->rcv_opts))
205 opts->flags |= TCP_OPTS_FLAG_WSCALE;
206 opts->wscale = tc->rcv_wscale;
207 len += TCP_OPTION_LEN_WINDOW_SCALE;
210 if (tcp_opts_tstamp (&tc->rcv_opts))
212 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
213 opts->tsval = tcp_time_tstamp (tc->c_thread_index);
214 opts->tsecr = tc->tsval_recent;
215 len += TCP_OPTION_LEN_TIMESTAMP;
218 if (tcp_opts_sack_permitted (&tc->rcv_opts))
220 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
221 len += TCP_OPTION_LEN_SACK_PERMITTED;
224 /* Align to needed boundary */
225 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
230 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
236 if (tcp_opts_tstamp (&tc->rcv_opts))
238 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
239 opts->tsval = tcp_tstamp (tc);
240 opts->tsecr = tc->tsval_recent;
241 len += TCP_OPTION_LEN_TIMESTAMP;
243 if (tcp_opts_sack_permitted (&tc->rcv_opts))
245 if (vec_len (tc->snd_sacks))
247 opts->flags |= TCP_OPTS_FLAG_SACK;
248 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
249 tc->snd_sack_pos = 0;
250 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
251 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
252 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
253 TCP_OPTS_MAX_SACK_BLOCKS);
254 tc->snd_sack_pos += opts->n_sack_blocks;
255 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
259 /* Align to needed boundary */
260 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
265 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
270 case TCP_STATE_ESTABLISHED:
271 case TCP_STATE_CLOSE_WAIT:
272 case TCP_STATE_FIN_WAIT_1:
273 case TCP_STATE_LAST_ACK:
274 case TCP_STATE_CLOSING:
275 case TCP_STATE_FIN_WAIT_2:
276 case TCP_STATE_TIME_WAIT:
277 case TCP_STATE_CLOSED:
278 return tcp_make_established_options (tc, opts);
279 case TCP_STATE_SYN_RCVD:
280 return tcp_make_synack_options (tc, opts);
281 case TCP_STATE_SYN_SENT:
282 return tcp_make_syn_options (tc, opts);
284 clib_warning ("State not handled! %d", state);
290 * Update burst send vars
292 * - Updates snd_mss to reflect the effective segment size that we can send
293 * by taking into account all TCP options, including SACKs.
294 * - Cache 'on the wire' options for reuse
295 * - Updates receive window which can be reused for a burst.
297 * This should *only* be called when doing bursts
300 tcp_update_burst_snd_vars (tcp_connection_t * tc)
302 tcp_main_t *tm = &tcp_main;
304 /* Compute options to be used for connection. These may be reused when
305 * sending data or to compute the effective mss (snd_mss) */
306 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
307 TCP_STATE_ESTABLISHED);
309 /* XXX check if MTU has been updated */
310 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
311 ASSERT (tc->snd_mss > 0);
313 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
316 tcp_update_rcv_wnd (tc);
318 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
319 tcp_bt_check_app_limited (tc);
321 if (tc->snd_una == tc->snd_nxt)
323 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
326 if (tc->flags & TCP_CONN_PSH_PENDING)
328 u32 max_deq = transport_max_tx_dequeue (&tc->connection);
329 /* Last byte marked for push */
330 tc->psh_seq = tc->snd_una + max_deq - 1;
335 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
337 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
338 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
339 b->total_length_not_including_first_buffer = 0;
341 vnet_buffer (b)->tcp.flags = 0;
342 /* Leave enough space for headers */
343 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
346 /* Compute TCP checksum in software when offloading is disabled for a connection */
348 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
349 ip46_address_t * src, ip46_address_t * dst)
352 u16 payload_length_host_byte_order;
355 /* Initialize checksum with ip header. */
356 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
357 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
358 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
360 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
362 sum0 = ip_csum_with_carry
363 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
364 sum0 = ip_csum_with_carry
365 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
368 return ip_calculate_l4_checksum (vm, p0, sum0,
369 payload_length_host_byte_order, NULL, 0,
374 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
375 ip46_address_t * src, ip46_address_t * dst)
378 u32 payload_length_host_byte_order;
380 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
382 clib_host_to_net_u32 (payload_length_host_byte_order +
383 (IP_PROTOCOL_TCP << 16));
385 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
386 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
388 return ip_calculate_l4_checksum (vm, p0, sum0,
389 payload_length_host_byte_order, NULL, 0,
394 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
397 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
399 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
400 vlib_main_t *vm = wrk->vm;
403 checksum = ip4_tcp_compute_checksum_custom
404 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
406 checksum = ip6_tcp_compute_checksum_custom
407 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
411 vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TCP_CKSUM);
420 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
423 tcp_options_t _snd_opts = {}, *snd_opts = &_snd_opts;
424 u8 tcp_opts_len, tcp_hdr_opts_len;
428 wnd = tcp_window_to_advertise (tc, state);
430 /* Make and write options */
431 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
432 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
434 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
435 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
437 tcp_options_write ((u8 *) (th + 1), snd_opts);
439 th->checksum = tcp_compute_checksum (tc, b);
441 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
445 transport_rx_fifo_req_deq_ntf (&tc->connection);
446 tcp_zero_rwnd_sent_on (tc);
449 tcp_zero_rwnd_sent_off (tc);
453 * Convert buffer to ACK
456 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
458 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
459 TCP_EVT (TCP_EVT_ACK_SENT, tc);
460 tc->rcv_las = tc->rcv_nxt;
464 * Convert buffer to FIN-ACK
467 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
469 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
473 * Convert buffer to SYN
476 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
478 u8 tcp_hdr_opts_len, tcp_opts_len;
481 tcp_options_t snd_opts;
483 initial_wnd = tcp_initial_window_to_advertise (tc);
485 /* Make and write options */
486 clib_memset (&snd_opts, 0, sizeof (snd_opts));
487 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
488 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
490 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
491 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
493 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
494 tcp_options_write ((u8 *) (th + 1), &snd_opts);
495 th->checksum = tcp_compute_checksum (tc, b);
499 * Convert buffer to SYN-ACK
502 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
504 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
505 u8 tcp_opts_len, tcp_hdr_opts_len;
509 clib_memset (snd_opts, 0, sizeof (*snd_opts));
510 initial_wnd = tcp_initial_window_to_advertise (tc);
511 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
512 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
514 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
515 tc->rcv_nxt, tcp_hdr_opts_len,
516 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
517 tcp_options_write ((u8 *) (th + 1), snd_opts);
519 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
520 th->checksum = tcp_compute_checksum (tc, b);
524 tcp_enqueue_half_open (tcp_worker_ctx_t *wrk, tcp_connection_t *tc,
525 vlib_buffer_t *b, u32 bi)
527 vlib_main_t *vm = wrk->vm;
529 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
532 session_add_pending_tx_buffer (vm->thread_index, bi,
533 wrk->tco_next_node[!tc->c_is_ip4]);
535 if (vm->thread_index == 0 && vlib_num_workers ())
536 session_queue_run_on_main_thread (vm);
540 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
543 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
546 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
547 wrk->tco_next_node[!is_ip4]);
551 tcp_buffer_make_reset (vlib_main_t *vm, vlib_buffer_t *b, u8 is_ip4)
553 ip4_address_t src_ip4 = {}, dst_ip4 = {};
554 ip6_address_t src_ip6, dst_ip6;
555 u16 src_port, dst_port;
556 u32 tmp, len, seq, ack;
563 * Find IP and TCP headers and glean information from them. Assumes
564 * buffer was parsed by something like @ref tcp_input_lookup_buffer
566 th = tcp_buffer_hdr (b);
570 ih4 = vlib_buffer_get_current (b);
571 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
572 src_ip4.as_u32 = ih4->src_address.as_u32;
573 dst_ip4.as_u32 = ih4->dst_address.as_u32;
577 ih6 = vlib_buffer_get_current (b);
578 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
579 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
580 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
583 src_port = th->src_port;
584 dst_port = th->dst_port;
585 flags = TCP_FLAG_RST;
588 * RFC 793. If the ACK bit is off, sequence number zero is used,
589 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
590 * If the ACK bit is on,
591 * <SEQ=SEG.ACK><CTL=RST>
595 seq = th->ack_number;
600 flags |= TCP_FLAG_ACK;
601 tmp = clib_net_to_host_u32 (th->seq_number);
602 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
603 ack = clib_host_to_net_u32 (tmp + len);
608 * Clear and reuse current buffer for reset
610 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
611 vlib_buffer_free_one (vm, b->next_buffer);
613 /* Zero all flags but free list index and trace flag */
614 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
615 /* Make sure new tcp header comes after current ip */
616 b->current_data = ((u8 *) th - b->data) + sizeof (tcp_header_t);
617 b->current_length = 0;
618 b->total_length_not_including_first_buffer = 0;
619 vnet_buffer (b)->tcp.flags = 0;
622 * Add TCP and IP headers
624 th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack,
625 sizeof (tcp_header_t), flags, 0);
629 ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4,
631 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
636 ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP);
637 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
645 * Send reset without reusing existing buffer
647 * It extracts connection info out of original packet
650 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
651 u32 thread_index, u8 is_ip4)
653 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
654 vlib_main_t *vm = wrk->vm;
656 u8 tcp_hdr_len, flags = 0;
657 tcp_header_t *th, *pkt_th;
659 ip4_header_t *pkt_ih4;
660 ip6_header_t *pkt_ih6;
662 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
664 tcp_worker_stats_inc (wrk, no_buffer, 1);
668 b = vlib_get_buffer (vm, bi);
669 tcp_init_buffer (vm, b);
670 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
672 /* Make and write options */
673 tcp_hdr_len = sizeof (tcp_header_t);
677 pkt_ih4 = vlib_buffer_get_current (pkt);
678 pkt_th = ip4_next_header (pkt_ih4);
682 pkt_ih6 = vlib_buffer_get_current (pkt);
683 pkt_th = ip6_next_header (pkt_ih6);
686 if (tcp_ack (pkt_th))
688 flags = TCP_FLAG_RST;
689 seq = pkt_th->ack_number;
690 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
691 ack = clib_host_to_net_u32 (ack);
695 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
697 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
700 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
701 seq, ack, tcp_hdr_len, flags, 0);
702 th->checksum = tcp_compute_checksum (tc, b);
704 tcp_enqueue_half_open (wrk, tc, b, bi);
705 TCP_EVT (TCP_EVT_RST_SENT, tc);
706 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
707 TCP_ERROR_RST_SENT, 1);
711 * Build and set reset packet for connection
714 tcp_send_reset (tcp_connection_t * tc)
716 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
717 vlib_main_t *vm = wrk->vm;
721 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
724 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
726 tcp_worker_stats_inc (wrk, no_buffer, 1);
729 b = vlib_get_buffer (vm, bi);
730 tcp_init_buffer (vm, b);
732 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
733 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
734 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
735 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
736 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
737 tc->rcv_nxt, tcp_hdr_opts_len, flags,
739 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
740 th->checksum = tcp_compute_checksum (tc, b);
741 ASSERT (opts_write_len == tc->snd_opts_len);
742 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
743 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
744 TCP_EVT (TCP_EVT_RST_SENT, tc);
745 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
746 TCP_ERROR_RST_SENT, 1);
752 * Builds a SYN packet for a half-open connection and sends it to tcp-output.
753 * The packet is handled by main thread and because half-open and established
754 * connections use the same pool the connection can be retrieved without
758 tcp_send_syn (tcp_connection_t * tc)
760 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
761 vlib_main_t *vm = wrk->vm;
766 * Setup retransmit and establish timers before requesting buffer
767 * such that we can return if we've ran out.
769 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
770 (u32) tc->rto * TCP_TO_TIMER_TICK);
772 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
774 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
775 tcp_cfg.alloc_err_timeout);
776 tcp_worker_stats_inc (wrk, no_buffer, 1);
780 b = vlib_get_buffer (vm, bi);
781 tcp_init_buffer (vm, b);
782 tcp_make_syn (tc, b);
784 /* Measure RTT with this */
785 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
786 tc->rtt_seq = tc->snd_nxt;
789 tcp_enqueue_half_open (wrk, tc, b, bi);
790 TCP_EVT (TCP_EVT_SYN_SENT, tc);
794 tcp_send_synack (tcp_connection_t * tc)
796 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
797 vlib_main_t *vm = wrk->vm;
801 ASSERT (tc->snd_una != tc->snd_nxt);
802 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
804 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
806 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
807 tcp_cfg.alloc_err_timeout);
808 tcp_worker_stats_inc (wrk, no_buffer, 1);
812 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
813 b = vlib_get_buffer (vm, bi);
814 tcp_init_buffer (vm, b);
815 tcp_make_synack (tc, b);
816 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
817 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
824 tcp_send_fin (tcp_connection_t * tc)
826 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
827 vlib_main_t *vm = wrk->vm;
832 fin_snt = tc->flags & TCP_CONN_FINSNT;
836 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
838 /* Out of buffers so program fin retransmit ASAP */
839 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
840 tcp_cfg.alloc_err_timeout);
844 /* Make sure retransmit retries a fin not data */
845 tc->flags |= TCP_CONN_FINSNT;
846 tcp_worker_stats_inc (wrk, no_buffer, 1);
850 /* If we have non-dupacks programmed, no need to send them */
851 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
852 tc->flags &= ~TCP_CONN_SNDACK;
854 b = vlib_get_buffer (vm, bi);
855 tcp_init_buffer (vm, b);
856 tcp_make_fin (tc, b);
857 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
858 TCP_EVT (TCP_EVT_FIN_SENT, tc);
859 /* Account for the FIN */
861 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
864 tc->flags |= TCP_CONN_FINSNT;
865 tc->flags &= ~TCP_CONN_FINPNDG;
870 * Push TCP header and update connection variables. Should only be called
871 * for segments with data, not for 'control' packets.
874 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
875 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
877 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
878 u32 advertise_wnd, data_len;
879 tcp_main_t *tm = &tcp_main;
882 data_len = b->current_length;
883 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
884 data_len += b->total_length_not_including_first_buffer;
886 vnet_buffer (b)->tcp.flags = 0;
887 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
890 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
892 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
895 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
897 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
899 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
901 if (seq_geq (tc->psh_seq, snd_nxt)
902 && seq_lt (tc->psh_seq, snd_nxt + data_len))
903 flags |= TCP_FLAG_PSH;
905 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
906 tc->rcv_nxt, tcp_hdr_opts_len, flags,
911 clib_memcpy_fast ((u8 *) (th + 1),
912 tm->wrk_ctx[tc->c_thread_index].cached_opts,
917 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
918 ASSERT (len == tc->snd_opts_len);
922 * Update connection variables
926 tc->snd_nxt += data_len;
927 tc->rcv_las = tc->rcv_nxt;
929 tc->bytes_out += data_len;
930 tc->data_segs_out += 1;
932 th->checksum = tcp_compute_checksum (tc, b);
934 TCP_EVT (TCP_EVT_PKTIZE, tc);
938 tcp_buffer_len (vlib_buffer_t * b)
940 u32 data_len = b->current_length;
941 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
942 data_len += b->total_length_not_including_first_buffer;
947 tcp_push_one_header (tcp_connection_t *tc, vlib_buffer_t *b)
949 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
950 tcp_bt_track_tx (tc, tcp_buffer_len (b));
952 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
953 /* update_snd_nxt */ 1);
955 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
960 tcp_session_push_header (transport_connection_t *tconn, vlib_buffer_t **bs,
963 tcp_connection_t *tc = (tcp_connection_t *) tconn;
967 vlib_prefetch_buffer_header (bs[2], STORE);
968 vlib_prefetch_buffer_header (bs[3], STORE);
970 tcp_push_one_header (tc, bs[0]);
971 tcp_push_one_header (tc, bs[1]);
979 vlib_prefetch_buffer_header (bs[1], STORE);
981 tcp_push_one_header (tc, bs[0]);
987 /* If not tracking an ACK, start tracking */
988 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
990 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
991 tc->rtt_seq = tc->snd_nxt;
993 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
995 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
996 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
1003 tcp_send_ack (tcp_connection_t * tc)
1005 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1006 vlib_main_t *vm = wrk->vm;
1010 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1012 tcp_update_rcv_wnd (tc);
1013 tcp_worker_stats_inc (wrk, no_buffer, 1);
1016 b = vlib_get_buffer (vm, bi);
1017 tcp_init_buffer (vm, b);
1018 tcp_make_ack (tc, b);
1019 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1023 tcp_program_ack (tcp_connection_t * tc)
1025 if (!(tc->flags & TCP_CONN_SNDACK))
1027 session_add_self_custom_tx_evt (&tc->connection, 1);
1028 tc->flags |= TCP_CONN_SNDACK;
1033 tcp_program_dupack (tcp_connection_t * tc)
1035 if (!(tc->flags & TCP_CONN_SNDACK))
1037 session_add_self_custom_tx_evt (&tc->connection, 1);
1038 tc->flags |= TCP_CONN_SNDACK;
1040 if (tc->pending_dupacks < 255)
1041 tc->pending_dupacks += 1;
1045 tcp_program_retransmit (tcp_connection_t * tc)
1047 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1049 session_add_self_custom_tx_evt (&tc->connection, 0);
1050 tc->flags |= TCP_CONN_RXT_PENDING;
1055 * Send window update ack
1057 * Ensures that it will be sent only once, after a zero rwnd has been
1058 * advertised in a previous ack, and only if rwnd has grown beyond a
1059 * configurable value.
1062 tcp_send_window_update_ack (tcp_connection_t * tc)
1064 if (tcp_zero_rwnd_sent (tc))
1066 tcp_update_rcv_wnd (tc);
1067 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1069 tcp_zero_rwnd_sent_off (tc);
1070 tcp_program_ack (tc);
1076 * Allocate a new buffer and build a new tcp segment
1078 * @param wrk tcp worker
1079 * @param tc connection for which the segment will be allocated
1080 * @param offset offset of the first byte in the tx fifo
1081 * @param max_deq_byte segment size
1082 * @param[out] b pointer to buffer allocated
1084 * @return the number of bytes in the segment or 0 if buffer cannot be
1085 * allocated or no data available
1088 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1089 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1091 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1092 vlib_main_t *vm = wrk->vm;
1097 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1102 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1105 * Allocate and fill in buffer(s)
1108 /* Easy case, buffer size greater than mss */
1109 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1111 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1113 tcp_worker_stats_inc (wrk, no_buffer, 1);
1116 *b = vlib_get_buffer (vm, bi);
1117 data = tcp_init_buffer (vm, *b);
1118 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1120 ASSERT (n_bytes == max_deq_bytes);
1121 b[0]->current_length = n_bytes;
1122 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1123 /* burst */ 0, /* update_snd_nxt */ 0);
1125 /* Split mss into multiple buffers */
1128 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1129 u16 n_peeked, len_to_deq;
1130 vlib_buffer_t *chain_b, *prev_b;
1133 /* Make sure we have enough buffers */
1134 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1135 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1136 CLIB_CACHE_LINE_BYTES);
1137 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1138 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1141 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1142 tcp_worker_stats_inc (wrk, no_buffer, 1);
1146 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1147 data = tcp_init_buffer (vm, *b);
1148 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1150 TRANSPORT_MAX_HDRS_LEN);
1151 b[0]->current_length = n_bytes;
1152 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1153 b[0]->total_length_not_including_first_buffer = 0;
1154 max_deq_bytes -= n_bytes;
1157 for (i = 1; i < n_bufs_per_seg; i++)
1160 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1161 chain_bi = wrk->tx_buffers[--n_bufs];
1162 chain_b = vlib_get_buffer (vm, chain_bi);
1163 chain_b->current_data = 0;
1164 data = vlib_buffer_get_current (chain_b);
1165 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1168 ASSERT (n_peeked == len_to_deq);
1169 n_bytes += n_peeked;
1170 chain_b->current_length = n_peeked;
1171 chain_b->next_buffer = 0;
1173 /* update previous buffer */
1174 prev_b->next_buffer = chain_bi;
1175 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1177 max_deq_bytes -= n_peeked;
1178 b[0]->total_length_not_including_first_buffer += n_peeked;
1181 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1182 /* burst */ 0, /* update_snd_nxt */ 0);
1184 if (PREDICT_FALSE (n_bufs))
1186 clib_warning ("not all buffers consumed");
1187 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1191 ASSERT (n_bytes > 0);
1192 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1198 * Build a retransmit segment
1200 * @return the number of bytes in the segment or 0 if there's nothing to
1204 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1205 tcp_connection_t * tc, u32 offset,
1206 u32 max_deq_bytes, vlib_buffer_t ** b)
1208 u32 start, available_bytes;
1211 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1212 ASSERT (max_deq_bytes != 0);
1215 * Make sure we can retransmit something
1217 available_bytes = transport_max_tx_dequeue (&tc->connection);
1218 ASSERT (available_bytes >= offset);
1219 available_bytes -= offset;
1220 if (!available_bytes)
1223 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1224 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1226 start = tc->snd_una + offset;
1227 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1229 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1233 tc->snd_rxt_bytes += n_bytes;
1235 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1236 tcp_bt_track_rxt (tc, start, start + n_bytes);
1238 tc->bytes_retrans += n_bytes;
1239 tc->segs_retrans += 1;
1240 tcp_worker_stats_inc (wrk, rxt_segs, 1);
1241 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1247 tcp_check_sack_reneging (tcp_connection_t * tc)
1249 sack_scoreboard_t *sb = &tc->sack_sb;
1250 sack_scoreboard_hole_t *hole;
1252 hole = scoreboard_first_hole (sb);
1253 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1256 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1260 * Reset congestion control, switch cwnd to loss window and try again.
1263 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1265 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1267 tc->prev_ssthresh = tc->ssthresh;
1268 tc->prev_cwnd = tc->cwnd;
1270 /* If we entrered loss without fast recovery, notify cc algo of the
1271 * congestion event such that it can update ssthresh and its state */
1272 if (!tcp_in_fastrecovery (tc))
1273 tcp_cc_congestion (tc);
1275 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1279 tc->cwnd_acc_bytes = 0;
1280 tc->tr_occurences += 1;
1281 tc->sack_sb.reorder = TCP_DUPACK_THRESHOLD;
1282 tc->sack_sb.rescue_rxt = tc->snd_una - 1;
1283 tcp_recovery_on (tc);
1287 tcp_timer_retransmit_handler (tcp_connection_t * tc)
1289 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1290 vlib_main_t *vm = wrk->vm;
1291 vlib_buffer_t *b = 0;
1294 tcp_worker_stats_inc (wrk, tr_events, 1);
1296 /* Should be handled by a different handler */
1297 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
1300 /* Wait-close and retransmit could pop at the same time */
1301 if (tc->state == TCP_STATE_CLOSED)
1304 if (tc->state >= TCP_STATE_ESTABLISHED)
1306 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1308 /* Lost FIN, retransmit and return */
1309 if (tc->flags & TCP_CONN_FINSNT)
1313 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1317 /* Shouldn't be here */
1318 if (tc->snd_una == tc->snd_nxt)
1320 ASSERT (!tcp_in_recovery (tc));
1325 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1326 * to persist timer timeout */
1327 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1330 tcp_update_rto (tc);
1333 /* Peer is dead or network connectivity is lost. Close connection.
1334 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1335 * a min rto of 0.2s we need to retry about 8 times. */
1336 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1338 tcp_send_reset (tc);
1339 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1340 session_transport_closing_notify (&tc->connection);
1341 session_transport_closed_notify (&tc->connection);
1342 tcp_connection_timers_reset (tc);
1343 tcp_program_cleanup (wrk, tc);
1344 tcp_worker_stats_inc (wrk, tr_abort, 1);
1348 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1350 tcp_check_sack_reneging (tc);
1351 scoreboard_rxt_mark_lost (&tc->sack_sb, tc->snd_una, tc->snd_nxt);
1354 /* Update send congestion to make sure that rxt has data to send */
1355 tc->snd_congestion = tc->snd_nxt;
1357 /* Send the first unacked segment. If we're short on buffers, return
1358 * as soon as possible */
1359 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1360 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1363 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
1364 tcp_cfg.alloc_err_timeout);
1368 bi = vlib_get_buffer_index (vm, b);
1369 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1371 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1372 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1375 if (tc->rto_boff == 1)
1377 tcp_cc_init_rxt_timeout (tc);
1378 /* Record timestamp. Eifel detection algorithm RFC3522 */
1379 tc->snd_rxt_ts = tcp_tstamp (tc);
1382 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1383 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1385 tcp_program_retransmit (tc);
1387 /* Retransmit SYN-ACK */
1388 else if (tc->state == TCP_STATE_SYN_RCVD)
1390 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1394 /* Passive open establish timeout */
1395 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1397 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1398 tcp_connection_timers_reset (tc);
1399 tcp_program_cleanup (wrk, tc);
1400 tcp_worker_stats_inc (wrk, tr_abort, 1);
1404 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1406 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT,
1407 tcp_cfg.alloc_err_timeout);
1408 tcp_worker_stats_inc (wrk, no_buffer, 1);
1413 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1414 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1416 ASSERT (tc->snd_una != tc->snd_nxt);
1417 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1419 b = vlib_get_buffer (vm, bi);
1420 tcp_init_buffer (vm, b);
1421 tcp_make_synack (tc, b);
1422 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1424 /* Retransmit timer already updated, just enqueue to output */
1425 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1429 ASSERT (tc->state == TCP_STATE_CLOSED);
1435 * SYN retransmit timer handler. Active open only.
1438 tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
1440 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1441 vlib_main_t *vm = wrk->vm;
1442 vlib_buffer_t *b = 0;
1445 /* Note: the connection may have transitioned to ESTABLISHED... */
1446 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
1449 /* Half-open connection actually moved to established but we were
1450 * waiting for syn retransmit to pop to call cleanup from the right
1452 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1454 if (tcp_half_open_connection_cleanup (tc))
1455 TCP_DBG ("could not remove half-open connection");
1459 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1462 /* Active open establish timeout */
1463 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1465 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
1466 tcp_connection_cleanup (tc);
1470 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1472 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1473 tcp_cfg.alloc_err_timeout);
1474 tcp_worker_stats_inc (wrk, no_buffer, 1);
1478 /* Try without increasing RTO a number of times. If this fails,
1479 * start growing RTO exponentially */
1481 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1482 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1484 b = vlib_get_buffer (vm, bi);
1485 tcp_init_buffer (vm, b);
1486 tcp_make_syn (tc, b);
1488 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1490 tcp_enqueue_half_open (wrk, tc, b, bi);
1492 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1493 (u32) tc->rto * TCP_TO_TIMER_TICK);
1497 * Got 0 snd_wnd from peer, try to do something about it.
1501 tcp_timer_persist_handler (tcp_connection_t * tc)
1503 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1504 u32 bi, max_snd_bytes, available_bytes, offset;
1505 tcp_main_t *tm = vnet_get_tcp_main ();
1506 vlib_main_t *vm = wrk->vm;
1511 /* Problem already solved or worse */
1512 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1513 || (tc->flags & TCP_CONN_FINSNT))
1514 goto update_scheduler;
1516 available_bytes = transport_max_tx_dequeue (&tc->connection);
1517 offset = tc->snd_nxt - tc->snd_una;
1519 /* Reprogram persist if no new bytes available to send. We may have data
1521 if (!available_bytes)
1523 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1527 if (available_bytes <= offset)
1528 goto update_scheduler;
1530 /* Increment RTO backoff */
1532 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1535 * Try to force the first unsent segment (or buffer)
1537 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1539 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1540 tcp_worker_stats_inc (wrk, no_buffer, 1);
1544 b = vlib_get_buffer (vm, bi);
1545 data = tcp_init_buffer (vm, b);
1547 tcp_validate_txf_size (tc, offset);
1548 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1549 max_snd_bytes = clib_min (clib_min (tc->snd_mss, available_bytes),
1550 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1551 if (tc->snd_wnd > 0)
1552 max_snd_bytes = clib_min (tc->snd_wnd, max_snd_bytes);
1553 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1555 b->current_length = n_bytes;
1556 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1557 || tc->snd_una == tc->snd_nxt
1558 || tc->rto_boff > 1));
1560 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1562 tcp_bt_check_app_limited (tc);
1563 tcp_bt_track_tx (tc, n_bytes);
1566 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1567 /* burst */ 0, /* update_snd_nxt */ 1);
1568 tcp_validate_txf_size (tc, tc->snd_nxt - tc->snd_una);
1569 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1571 /* Just sent new data, enable retransmit */
1572 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1578 if (tcp_is_descheduled (tc))
1579 transport_connection_reschedule (&tc->connection);
1583 * Retransmit first unacked segment
1586 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1588 vlib_main_t *vm = wrk->vm;
1592 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1594 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1598 bi = vlib_get_buffer_index (vm, b);
1599 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1605 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1608 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1609 vlib_main_t *vm = wrk->vm;
1610 vlib_buffer_t *b = 0;
1612 offset = tc->snd_nxt - tc->snd_una;
1613 available_wnd = tc->snd_wnd - offset;
1614 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1616 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1617 tcp_bt_check_app_limited (tc);
1619 while (n_segs < burst_size)
1621 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1625 bi = vlib_get_buffer_index (vm, b);
1626 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1627 offset += n_written;
1630 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1631 tcp_bt_track_tx (tc, n_written);
1633 tc->snd_nxt += n_written;
1641 * Estimate send space using proportional rate reduction (RFC6937)
1644 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1649 pipe = tcp_flight_size (tc);
1650 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1652 if (pipe > tc->ssthresh)
1654 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1660 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1661 space = clib_min (tc->ssthresh - pipe, limit);
1663 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1668 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1669 sack_scoreboard_t * sb)
1671 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1672 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1674 if (tcp_fastrecovery_first (tc))
1677 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1681 tcp_max_tx_deq (tcp_connection_t * tc)
1683 return (transport_max_tx_dequeue (&tc->connection)
1684 - (tc->snd_nxt - tc->snd_una));
1687 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1688 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1689 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1692 * Do retransmit with SACKs
1695 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1698 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1699 u8 snd_limited = 0, can_rescue = 0;
1700 u32 bi, max_deq, burst_bytes;
1701 sack_scoreboard_hole_t *hole;
1702 vlib_main_t *vm = wrk->vm;
1703 vlib_buffer_t *b = 0;
1704 sack_scoreboard_t *sb;
1707 ASSERT (tcp_in_cong_recovery (tc));
1709 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1710 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1713 tcp_program_retransmit (tc);
1717 if (tcp_in_recovery (tc))
1718 snd_space = tcp_available_cc_snd_space (tc);
1720 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1722 if (snd_space < tc->snd_mss)
1727 /* Check if snd_una is a lost retransmit */
1728 if (pool_elts (sb->holes)
1729 && seq_gt (sb->high_sacked, tc->snd_congestion)
1730 && tc->rxt_head != tc->snd_una
1731 && tcp_retransmit_should_retry_head (tc, sb))
1733 max_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1734 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1737 tcp_program_retransmit (tc);
1740 bi = vlib_get_buffer_index (vm, b);
1741 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1744 tc->rxt_head = tc->snd_una;
1745 tc->rxt_delivered += n_written;
1746 tc->prr_delivered += n_written;
1747 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1750 tcp_fastrecovery_first_off (tc);
1752 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1753 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1755 max_deq = transport_max_tx_dequeue (&tc->connection);
1756 max_deq -= tc->snd_nxt - tc->snd_una;
1758 while (snd_space > 0 && n_segs < burst_size)
1760 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1764 /* We are out of lost holes to retransmit so send some new data. */
1765 if (max_deq > tc->snd_mss)
1770 /* Make sure we don't exceed available window and leave space
1771 * for one more packet, to avoid zero window acks */
1772 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1773 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1774 snd_space = clib_min (snd_space, av_wnd);
1775 snd_space = clib_min (max_deq, snd_space);
1776 burst_size = clib_min (burst_size - n_segs,
1777 snd_space / tc->snd_mss);
1778 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1779 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1780 if (max_deq > n_segs_new * tc->snd_mss)
1781 tcp_program_retransmit (tc);
1783 n_segs += n_segs_new;
1787 if (!can_rescue || scoreboard_rescue_rxt_valid (sb, tc))
1790 /* If rescue rxt undefined or less than snd_una then one segment of
1791 * up to SMSS octets that MUST include the highest outstanding
1792 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1793 * RecoveryPoint. HighRxt MUST NOT be updated.
1795 hole = scoreboard_last_hole (sb);
1796 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1797 max_bytes = clib_min (max_bytes, snd_space);
1798 offset = hole->end - tc->snd_una - max_bytes;
1799 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1804 sb->rescue_rxt = tc->snd_congestion;
1805 bi = vlib_get_buffer_index (vm, b);
1806 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1811 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1812 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1816 offset = sb->high_rxt - tc->snd_una;
1817 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1819 ASSERT (n_written <= snd_space);
1821 /* Nothing left to retransmit */
1825 bi = vlib_get_buffer_index (vm, b);
1826 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1828 sb->high_rxt += n_written;
1829 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1831 snd_space -= n_written;
1836 tcp_program_retransmit (tc);
1840 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
1845 * Fast retransmit without SACK info
1848 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1851 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
1852 u32 burst_bytes, sent_bytes;
1853 vlib_main_t *vm = wrk->vm;
1854 int snd_space, n_segs = 0;
1858 ASSERT (tcp_in_cong_recovery (tc));
1859 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1861 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1862 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1865 tcp_program_retransmit (tc);
1869 snd_space = tcp_available_cc_snd_space (tc);
1870 cc_limited = snd_space < burst_bytes;
1872 if (!tcp_fastrecovery_first (tc))
1875 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1877 while (snd_space > 0 && n_segs < burst_size)
1879 max_bytes = clib_min (tc->snd_mss,
1880 tc->snd_congestion - tc->snd_una - offset);
1883 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1886 /* Nothing left to retransmit */
1890 bi = vlib_get_buffer_index (vm, b);
1891 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1892 snd_space -= n_written;
1893 offset += n_written;
1897 if (n_segs == burst_size)
1902 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1903 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1906 max_deq = transport_max_tx_dequeue (&tc->connection);
1907 max_deq -= tc->snd_nxt - tc->snd_una;
1910 snd_space = clib_min (max_deq, snd_space);
1911 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1912 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1913 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
1914 tcp_program_retransmit (tc);
1915 n_segs += n_segs_now;
1919 tcp_fastrecovery_first_off (tc);
1921 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1922 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1923 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1929 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1933 if (!tc->pending_dupacks)
1935 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1936 || tc->state != TCP_STATE_ESTABLISHED)
1944 /* If we're supposed to send dupacks but have no ooo data
1945 * send only one ack */
1946 if (!vec_len (tc->snd_sacks))
1949 tc->dupacks_out += 1;
1950 tc->pending_dupacks = 0;
1954 /* Start with first sack block */
1955 tc->snd_sack_pos = 0;
1957 /* Generate enough dupacks to cover all sack blocks. Do not generate
1958 * more sacks than the number of packets received. But do generate at
1959 * least 3, i.e., the number needed to signal congestion, if needed. */
1960 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1961 n_acks = clib_min (n_acks, tc->pending_dupacks);
1962 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1963 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1966 if (n_acks < max_burst_size)
1968 tc->pending_dupacks = 0;
1969 tc->snd_sack_pos = 0;
1970 tc->dupacks_out += n_acks;
1975 TCP_DBG ("constrained by burst size");
1976 tc->pending_dupacks = n_acks - max_burst_size;
1977 tc->dupacks_out += max_burst_size;
1978 tcp_program_dupack (tc);
1979 return max_burst_size;
1984 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
1986 tcp_worker_ctx_t *wrk;
1989 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
1992 wrk = tcp_get_worker (tc->c_thread_index);
1994 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1995 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
1997 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2003 tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
2005 tcp_connection_t *tc = (tcp_connection_t *) conn;
2008 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2010 tc->flags &= ~TCP_CONN_RXT_PENDING;
2011 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
2014 if (!(tc->flags & TCP_CONN_SNDACK))
2017 tc->flags &= ~TCP_CONN_SNDACK;
2019 /* We have retransmitted packets and no dupack */
2020 if (n_segs && !tc->pending_dupacks)
2023 if (sp->max_burst_size <= n_segs)
2025 tcp_program_ack (tc);
2029 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
2033 #endif /* CLIB_MARCH_VARIANT */
2036 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2037 u16 * next0, u32 * error0)
2039 ip_adjacency_t *adj;
2042 /* Not thread safe but as long as the connection exists the adj should
2044 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2046 if (ai == ADJ_INDEX_INVALID)
2048 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2049 *next0 = TCP_OUTPUT_NEXT_DROP;
2050 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2055 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2056 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2057 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2058 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2061 *next0 = TCP_OUTPUT_NEXT_DROP;
2062 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2064 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2068 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2069 u32 * to_next, u32 n_bufs)
2071 tcp_connection_t *tc;
2077 for (i = 0; i < n_bufs; i++)
2079 b = vlib_get_buffer (vm, to_next[i]);
2080 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2082 th = vlib_buffer_get_current (b);
2083 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2085 t = vlib_add_trace (vm, node, b, sizeof (*t));
2086 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2087 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2092 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2093 tcp_connection_t * tc0, u8 is_ip4)
2095 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2096 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2097 b0->current_length);
2100 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2101 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2103 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2104 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
2108 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2110 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2113 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2115 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2116 data_len += b->total_length_not_including_first_buffer;
2118 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2122 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2123 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2124 b->flags |= VNET_BUFFER_F_GSO;
2125 vnet_buffer2 (b)->gso_l4_hdr_sz =
2126 sizeof (tcp_header_t) + tc->snd_opts_len;
2127 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2132 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2133 vlib_node_runtime_t * error_node, u16 * next0,
2136 /* If next_index is not drop use it */
2137 if (tc0->next_node_index)
2139 *next0 = tc0->next_node_index;
2140 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2144 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2147 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2148 vnet_buffer (b0)->sw_if_index[VLIB_RX] = tc0->sw_if_index;
2154 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2155 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2157 if (PREDICT_FALSE (error0))
2159 b0->error = error_node->errors[error0];
2168 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2169 vlib_frame_t * frame, int is_ip4)
2171 u32 n_left_from, *from, thread_index = vm->thread_index;
2172 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2173 u16 nexts[VLIB_FRAME_SIZE], *next;
2174 u16 err_counters[TCP_N_ERROR] = { 0 };
2176 from = vlib_frame_vector_args (frame);
2177 n_left_from = frame->n_vectors;
2178 tcp_update_time_now (tcp_get_worker (thread_index));
2180 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2181 tcp46_output_trace_frame (vm, node, from, n_left_from);
2183 vlib_get_buffers (vm, from, bufs, n_left_from);
2187 while (n_left_from >= 4)
2189 tcp_connection_t *tc0, *tc1;
2192 vlib_prefetch_buffer_header (b[2], STORE);
2193 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2195 vlib_prefetch_buffer_header (b[3], STORE);
2196 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2199 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2201 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2204 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2206 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2207 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2209 tcp_check_if_gso (tc0, b[0]);
2210 tcp_check_if_gso (tc1, b[1]);
2212 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2213 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2219 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2220 tcp_check_if_gso (tc0, b[0]);
2221 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2225 tcp_inc_err_counter (err_counters, TCP_ERROR_INVALID_CONNECTION,
2227 next[0] = TCP_OUTPUT_NEXT_DROP;
2231 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2232 tcp_check_if_gso (tc1, b[1]);
2233 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2237 tcp_inc_err_counter (err_counters, TCP_ERROR_INVALID_CONNECTION,
2239 next[1] = TCP_OUTPUT_NEXT_DROP;
2247 while (n_left_from > 0)
2249 tcp_connection_t *tc0;
2251 if (n_left_from > 1)
2253 vlib_prefetch_buffer_header (b[1], STORE);
2254 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2257 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2260 if (PREDICT_TRUE (tc0 != 0))
2262 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2263 tcp_check_if_gso (tc0, b[0]);
2264 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2268 tcp_inc_err_counter (err_counters, TCP_ERROR_INVALID_CONNECTION, 1);
2269 next[0] = TCP_OUTPUT_NEXT_DROP;
2277 tcp_store_err_counters (output, err_counters);
2278 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2279 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2280 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2281 return frame->n_vectors;
2284 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2285 vlib_frame_t * from_frame)
2287 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2290 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2291 vlib_frame_t * from_frame)
2293 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2297 VLIB_REGISTER_NODE (tcp4_output_node) =
2299 .name = "tcp4-output",
2300 /* Takes a vector of packets. */
2301 .vector_size = sizeof (u32),
2302 .n_errors = TCP_N_ERROR,
2303 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2304 .error_counters = tcp_output_error_counters,
2305 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2307 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2308 foreach_tcp4_output_next
2311 .format_buffer = format_tcp_header,
2312 .format_trace = format_tcp_tx_trace,
2317 VLIB_REGISTER_NODE (tcp6_output_node) =
2319 .name = "tcp6-output",
2320 /* Takes a vector of packets. */
2321 .vector_size = sizeof (u32),
2322 .n_errors = TCP_N_ERROR,
2323 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2324 .error_counters = tcp_output_error_counters,
2325 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2327 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2328 foreach_tcp6_output_next
2331 .format_buffer = format_tcp_header,
2332 .format_trace = format_tcp_tx_trace,
2336 typedef enum _tcp_reset_next
2338 TCP_RESET_NEXT_DROP,
2339 TCP_RESET_NEXT_IP_LOOKUP,
2343 #define foreach_tcp4_reset_next \
2344 _(DROP, "error-drop") \
2345 _(IP_LOOKUP, "ip4-lookup")
2347 #define foreach_tcp6_reset_next \
2348 _(DROP, "error-drop") \
2349 _(IP_LOOKUP, "ip6-lookup")
2352 tcp_reset_trace_frame (vlib_main_t *vm, vlib_node_runtime_t *node,
2353 vlib_buffer_t **bs, u32 n_bufs, u8 is_ip4)
2359 for (i = 0; i < n_bufs; i++)
2361 if (bs[i]->flags & VLIB_BUFFER_IS_TRACED)
2363 tcp = vlib_buffer_get_current (bs[i]);
2364 t = vlib_add_trace (vm, node, bs[i], sizeof (*t));
2368 ip4_header_t *ih4 = vlib_buffer_get_current (bs[i]);
2369 tcp = ip4_next_header (ih4);
2370 t->tcp_connection.c_lcl_ip.ip4 = ih4->dst_address;
2371 t->tcp_connection.c_rmt_ip.ip4 = ih4->src_address;
2372 t->tcp_connection.c_is_ip4 = 1;
2376 ip6_header_t *ih6 = vlib_buffer_get_current (bs[i]);
2377 tcp = ip6_next_header (ih6);
2378 t->tcp_connection.c_lcl_ip.ip6 = ih6->dst_address;
2379 t->tcp_connection.c_rmt_ip.ip6 = ih6->src_address;
2381 t->tcp_connection.c_lcl_port = tcp->dst_port;
2382 t->tcp_connection.c_rmt_port = tcp->src_port;
2383 t->tcp_connection.c_proto = TRANSPORT_PROTO_TCP;
2384 clib_memcpy_fast (&t->tcp_header, tcp, sizeof (t->tcp_header));
2390 tcp46_reset_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2391 vlib_frame_t *frame, u8 is_ip4)
2393 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2394 u16 nexts[VLIB_FRAME_SIZE], *next;
2395 u32 n_left_from, *from;
2397 from = vlib_frame_vector_args (frame);
2398 n_left_from = frame->n_vectors;
2399 vlib_get_buffers (vm, from, bufs, n_left_from);
2404 while (n_left_from > 0)
2406 tcp_buffer_make_reset (vm, b[0], is_ip4);
2408 /* IP lookup in fib where it was received. Previous value
2409 * was overwritten by tcp-input */
2410 vnet_buffer (b[0])->sw_if_index[VLIB_TX] =
2411 vec_elt (ip4_main.fib_index_by_sw_if_index,
2412 vnet_buffer (b[0])->sw_if_index[VLIB_RX]);
2414 b[0]->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2415 next[0] = TCP_RESET_NEXT_IP_LOOKUP;
2422 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2423 tcp_reset_trace_frame (vm, node, bufs, frame->n_vectors, is_ip4);
2425 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2427 vlib_node_increment_counter (vm, node->node_index, TCP_ERROR_RST_SENT,
2430 return frame->n_vectors;
2433 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2434 vlib_frame_t * from_frame)
2436 return tcp46_reset_inline (vm, node, from_frame, 1);
2439 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2440 vlib_frame_t * from_frame)
2442 return tcp46_reset_inline (vm, node, from_frame, 0);
2446 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2447 .name = "tcp4-reset",
2448 .vector_size = sizeof (u32),
2449 .n_errors = TCP_N_ERROR,
2450 .error_counters = tcp_output_error_counters,
2451 .n_next_nodes = TCP_RESET_N_NEXT,
2453 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2454 foreach_tcp4_reset_next
2457 .format_trace = format_tcp_tx_trace,
2462 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2463 .name = "tcp6-reset",
2464 .vector_size = sizeof (u32),
2465 .n_errors = TCP_N_ERROR,
2466 .error_counters = tcp_output_error_counters,
2467 .n_next_nodes = TCP_RESET_N_NEXT,
2469 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2470 foreach_tcp6_reset_next
2473 .format_trace = format_tcp_tx_trace,
2478 * fd.io coding-style-patch-verification: ON
2481 * eval: (c-set-style "gnu")