2 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vnet/tcp/tcp.h>
17 #include <vnet/tcp/tcp_inlines.h>
20 typedef enum _tcp_output_next
23 TCP_OUTPUT_NEXT_IP_LOOKUP,
24 TCP_OUTPUT_NEXT_IP_REWRITE,
25 TCP_OUTPUT_NEXT_IP_ARP,
29 #define foreach_tcp4_output_next \
30 _ (DROP, "error-drop") \
31 _ (IP_LOOKUP, "ip4-lookup") \
32 _ (IP_REWRITE, "ip4-rewrite") \
35 #define foreach_tcp6_output_next \
36 _ (DROP, "error-drop") \
37 _ (IP_LOOKUP, "ip6-lookup") \
38 _ (IP_REWRITE, "ip6-rewrite") \
39 _ (IP_ARP, "ip6-discover-neighbor")
41 static char *tcp_error_strings[] = {
42 #define tcp_error(n,s) s,
43 #include <vnet/tcp/tcp_error.def>
49 tcp_header_t tcp_header;
50 tcp_connection_t tcp_connection;
54 format_tcp_tx_trace (u8 * s, va_list * args)
56 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
57 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
58 tcp_tx_trace_t *t = va_arg (*args, tcp_tx_trace_t *);
59 tcp_connection_t *tc = &t->tcp_connection;
60 u32 indent = format_get_indent (s);
62 s = format (s, "%U state %U\n%U%U", format_tcp_connection_id, tc,
63 format_tcp_state, tc->state, format_white_space, indent,
64 format_tcp_header, &t->tcp_header, 128);
69 #ifndef CLIB_MARCH_VARIANT
71 tcp_window_compute_scale (u32 window)
74 while (wnd_scale < TCP_MAX_WND_SCALE && (window >> wnd_scale) > TCP_WND_MAX)
80 * TCP's initial window
83 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
85 /* RFC 6928 recommends the value lower. However at the time our connections
86 * are initialized, fifos may not be allocated. Therefore, advertise the
87 * smallest possible unscaled window size and update once fifos are
88 * assigned to the session.
91 tcp_update_rcv_mss (tc);
92 TCP_IW_N_SEGMENTS * tc->mss;
94 return tcp_cfg.min_rx_fifo;
98 * Compute initial window and scale factor. As per RFC1323, window field in
99 * SYN and SYN-ACK segments is never scaled.
102 tcp_initial_window_to_advertise (tcp_connection_t * tc)
104 /* Compute rcv wscale only if peer advertised support for it */
105 if (tc->state != TCP_STATE_SYN_RCVD || tcp_opts_wscale (&tc->rcv_opts))
106 tc->rcv_wscale = tcp_window_compute_scale (tcp_cfg.max_rx_fifo);
108 tc->rcv_wnd = tcp_initial_wnd_unscaled (tc);
110 return clib_min (tc->rcv_wnd, TCP_WND_MAX);
114 tcp_update_rcv_wnd (tcp_connection_t * tc)
116 u32 available_space, wnd;
120 * Figure out how much space we have available
122 available_space = transport_max_rx_enqueue (&tc->connection);
123 if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
130 * Use the above and what we know about what we've previously advertised
131 * to compute the new window
133 observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
135 /* Bad. Thou shalt not shrink */
136 if (PREDICT_FALSE ((i32) available_space < observed_wnd))
138 wnd = clib_max (observed_wnd, 0);
139 TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
143 wnd = available_space;
146 /* Make sure we have a multiple of 1 << rcv_wscale. We round up to
147 * avoid advertising a window less than mss which could happen if
148 * 1 << rcv_wscale < mss */
149 if (wnd && tc->rcv_wscale)
150 wnd = round_pow2 (wnd, 1 << tc->rcv_wscale);
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 tcp_make_syn_options (tcp_connection_t * tc, tcp_options_t * opts)
173 opts->flags |= TCP_OPTS_FLAG_MSS;
175 len += TCP_OPTION_LEN_MSS;
177 opts->flags |= TCP_OPTS_FLAG_WSCALE;
178 opts->wscale = tc->rcv_wscale;
179 len += TCP_OPTION_LEN_WINDOW_SCALE;
181 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
182 opts->tsval = tcp_time_now ();
184 len += TCP_OPTION_LEN_TIMESTAMP;
188 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
189 len += TCP_OPTION_LEN_SACK_PERMITTED;
192 /* Align to needed boundary */
193 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
198 tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
202 opts->flags |= TCP_OPTS_FLAG_MSS;
204 len += TCP_OPTION_LEN_MSS;
206 if (tcp_opts_wscale (&tc->rcv_opts))
208 opts->flags |= TCP_OPTS_FLAG_WSCALE;
209 opts->wscale = tc->rcv_wscale;
210 len += TCP_OPTION_LEN_WINDOW_SCALE;
213 if (tcp_opts_tstamp (&tc->rcv_opts))
215 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
216 opts->tsval = tcp_time_now ();
217 opts->tsecr = tc->tsval_recent;
218 len += TCP_OPTION_LEN_TIMESTAMP;
221 if (tcp_opts_sack_permitted (&tc->rcv_opts))
223 opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
224 len += TCP_OPTION_LEN_SACK_PERMITTED;
227 /* Align to needed boundary */
228 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
233 tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
239 if (tcp_opts_tstamp (&tc->rcv_opts))
241 opts->flags |= TCP_OPTS_FLAG_TSTAMP;
242 opts->tsval = tcp_tstamp (tc);
243 opts->tsecr = tc->tsval_recent;
244 len += TCP_OPTION_LEN_TIMESTAMP;
246 if (tcp_opts_sack_permitted (&tc->rcv_opts))
248 if (vec_len (tc->snd_sacks))
250 opts->flags |= TCP_OPTS_FLAG_SACK;
251 if (tc->snd_sack_pos >= vec_len (tc->snd_sacks))
252 tc->snd_sack_pos = 0;
253 opts->sacks = &tc->snd_sacks[tc->snd_sack_pos];
254 opts->n_sack_blocks = vec_len (tc->snd_sacks) - tc->snd_sack_pos;
255 opts->n_sack_blocks = clib_min (opts->n_sack_blocks,
256 TCP_OPTS_MAX_SACK_BLOCKS);
257 tc->snd_sack_pos += opts->n_sack_blocks;
258 len += 2 + TCP_OPTION_LEN_SACK_BLOCK * opts->n_sack_blocks;
262 /* Align to needed boundary */
263 len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
268 tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
273 case TCP_STATE_ESTABLISHED:
274 case TCP_STATE_CLOSE_WAIT:
275 case TCP_STATE_FIN_WAIT_1:
276 case TCP_STATE_LAST_ACK:
277 case TCP_STATE_CLOSING:
278 case TCP_STATE_FIN_WAIT_2:
279 case TCP_STATE_TIME_WAIT:
280 case TCP_STATE_CLOSED:
281 return tcp_make_established_options (tc, opts);
282 case TCP_STATE_SYN_RCVD:
283 return tcp_make_synack_options (tc, opts);
284 case TCP_STATE_SYN_SENT:
285 return tcp_make_syn_options (tc, opts);
287 clib_warning ("State not handled! %d", state);
293 * Update burst send vars
295 * - Updates snd_mss to reflect the effective segment size that we can send
296 * by taking into account all TCP options, including SACKs.
297 * - Cache 'on the wire' options for reuse
298 * - Updates receive window which can be reused for a burst.
300 * This should *only* be called when doing bursts
303 tcp_update_burst_snd_vars (tcp_connection_t * tc)
305 tcp_main_t *tm = &tcp_main;
307 /* Compute options to be used for connection. These may be reused when
308 * sending data or to compute the effective mss (snd_mss) */
309 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts,
310 TCP_STATE_ESTABLISHED);
312 /* XXX check if MTU has been updated */
313 tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
314 ASSERT (tc->snd_mss > 0);
316 tcp_options_write (tm->wrk_ctx[tc->c_thread_index].cached_opts,
319 tcp_update_rcv_wnd (tc);
321 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
322 tcp_bt_check_app_limited (tc);
324 if (tc->snd_una == tc->snd_nxt)
326 tcp_cc_event (tc, TCP_CC_EVT_START_TX);
327 tcp_connection_tx_pacer_reset (tc, tc->cwnd, TRANSPORT_PACER_MIN_BURST);
331 #endif /* CLIB_MARCH_VARIANT */
334 tcp_reuse_buffer (vlib_main_t * vm, vlib_buffer_t * b)
336 if (b->flags & VLIB_BUFFER_NEXT_PRESENT)
337 vlib_buffer_free_one (vm, b->next_buffer);
338 /* Zero all flags but free list index and trace flag */
339 b->flags &= VLIB_BUFFER_NEXT_PRESENT - 1;
341 b->current_length = 0;
342 b->total_length_not_including_first_buffer = 0;
343 vnet_buffer (b)->tcp.flags = 0;
345 /* Leave enough space for headers */
346 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
349 #ifndef CLIB_MARCH_VARIANT
351 tcp_init_buffer (vlib_main_t * vm, vlib_buffer_t * b)
353 ASSERT ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
354 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
355 b->total_length_not_including_first_buffer = 0;
357 vnet_buffer (b)->tcp.flags = 0;
358 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
359 /* Leave enough space for headers */
360 return vlib_buffer_make_headroom (b, TRANSPORT_MAX_HDRS_LEN);
364 /* Compute TCP checksum in software when offloading is disabled for a connection */
366 ip6_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
367 ip46_address_t * src, ip46_address_t * dst)
370 u16 payload_length_host_byte_order;
373 /* Initialize checksum with ip header. */
374 sum0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, p0)) +
375 clib_host_to_net_u16 (IP_PROTOCOL_TCP);
376 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
378 for (i = 0; i < ARRAY_LEN (src->ip6.as_uword); i++)
380 sum0 = ip_csum_with_carry
381 (sum0, clib_mem_unaligned (&src->ip6.as_uword[i], uword));
382 sum0 = ip_csum_with_carry
383 (sum0, clib_mem_unaligned (&dst->ip6.as_uword[i], uword));
386 return ip_calculate_l4_checksum (vm, p0, sum0,
387 payload_length_host_byte_order, NULL, 0,
392 ip4_tcp_compute_checksum_custom (vlib_main_t * vm, vlib_buffer_t * p0,
393 ip46_address_t * src, ip46_address_t * dst)
396 u32 payload_length_host_byte_order;
398 payload_length_host_byte_order = vlib_buffer_length_in_chain (vm, p0);
400 clib_host_to_net_u32 (payload_length_host_byte_order +
401 (IP_PROTOCOL_TCP << 16));
403 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&src->ip4, u32));
404 sum0 = ip_csum_with_carry (sum0, clib_mem_unaligned (&dst->ip4, u32));
406 return ip_calculate_l4_checksum (vm, p0, sum0,
407 payload_length_host_byte_order, NULL, 0,
412 tcp_compute_checksum (tcp_connection_t * tc, vlib_buffer_t * b)
415 if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
417 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
418 vlib_main_t *vm = wrk->vm;
421 checksum = ip4_tcp_compute_checksum_custom
422 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
424 checksum = ip6_tcp_compute_checksum_custom
425 (vm, b, &tc->c_lcl_ip, &tc->c_rmt_ip);
429 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
438 tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
441 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
442 u8 tcp_opts_len, tcp_hdr_opts_len;
446 wnd = tcp_window_to_advertise (tc, state);
448 /* Make and write options */
449 tcp_opts_len = tcp_make_established_options (tc, snd_opts);
450 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
452 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
453 tc->rcv_nxt, tcp_hdr_opts_len, flags, wnd);
455 tcp_options_write ((u8 *) (th + 1), snd_opts);
457 th->checksum = tcp_compute_checksum (tc, b);
459 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
462 tcp_zero_rwnd_sent_on (tc);
464 tcp_zero_rwnd_sent_off (tc);
468 * Convert buffer to ACK
471 tcp_make_ack (tcp_connection_t * tc, vlib_buffer_t * b)
473 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_ACK);
474 TCP_EVT (TCP_EVT_ACK_SENT, tc);
475 tc->rcv_las = tc->rcv_nxt;
479 * Convert buffer to FIN-ACK
482 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
484 tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
488 * Convert buffer to SYN
491 tcp_make_syn (tcp_connection_t * tc, vlib_buffer_t * b)
493 u8 tcp_hdr_opts_len, tcp_opts_len;
496 tcp_options_t snd_opts;
498 initial_wnd = tcp_initial_window_to_advertise (tc);
500 /* Make and write options */
501 clib_memset (&snd_opts, 0, sizeof (snd_opts));
502 tcp_opts_len = tcp_make_syn_options (tc, &snd_opts);
503 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
505 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
506 tc->rcv_nxt, tcp_hdr_opts_len, TCP_FLAG_SYN,
508 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
509 tcp_options_write ((u8 *) (th + 1), &snd_opts);
510 th->checksum = tcp_compute_checksum (tc, b);
514 * Convert buffer to SYN-ACK
517 tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
519 tcp_options_t _snd_opts, *snd_opts = &_snd_opts;
520 u8 tcp_opts_len, tcp_hdr_opts_len;
524 clib_memset (snd_opts, 0, sizeof (*snd_opts));
525 initial_wnd = tcp_initial_window_to_advertise (tc);
526 tcp_opts_len = tcp_make_synack_options (tc, snd_opts);
527 tcp_hdr_opts_len = tcp_opts_len + sizeof (tcp_header_t);
529 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->iss,
530 tc->rcv_nxt, tcp_hdr_opts_len,
531 TCP_FLAG_SYN | TCP_FLAG_ACK, initial_wnd);
532 tcp_options_write ((u8 *) (th + 1), snd_opts);
534 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
535 th->checksum = tcp_compute_checksum (tc, b);
539 tcp_enqueue_to_ip_lookup (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
540 u8 is_ip4, u32 fib_index)
542 tcp_main_t *tm = &tcp_main;
543 vlib_main_t *vm = wrk->vm;
545 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
548 vnet_buffer (b)->sw_if_index[VLIB_TX] = fib_index;
549 vnet_buffer (b)->sw_if_index[VLIB_RX] = 0;
551 tcp_trajectory_add_start (b, 1);
553 session_add_pending_tx_buffer (vm->thread_index, bi,
554 tm->ipl_next_node[!is_ip4]);
556 if (vm->thread_index == 0 && vlib_num_workers ())
557 session_queue_run_on_main_thread (wrk->vm);
561 tcp_enqueue_to_output (tcp_worker_ctx_t * wrk, vlib_buffer_t * b, u32 bi,
564 b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
567 session_add_pending_tx_buffer (wrk->vm->thread_index, bi,
568 wrk->tco_next_node[!is_ip4]);
571 #endif /* CLIB_MARCH_VARIANT */
574 tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b, u8 is_ip4)
579 ip4_address_t src_ip4, dst_ip4;
580 ip6_address_t src_ip6, dst_ip6;
581 u16 src_port, dst_port;
582 u32 tmp, len, seq, ack;
585 /* Find IP and TCP headers */
586 th = tcp_buffer_hdr (b);
588 /* Save src and dst ip */
591 ih4 = vlib_buffer_get_current (b);
592 ASSERT ((ih4->ip_version_and_header_length & 0xF0) == 0x40);
593 src_ip4.as_u32 = ih4->src_address.as_u32;
594 dst_ip4.as_u32 = ih4->dst_address.as_u32;
598 ih6 = vlib_buffer_get_current (b);
599 ASSERT ((ih6->ip_version_traffic_class_and_flow_label & 0xF0) == 0x60);
600 clib_memcpy_fast (&src_ip6, &ih6->src_address, sizeof (ip6_address_t));
601 clib_memcpy_fast (&dst_ip6, &ih6->dst_address, sizeof (ip6_address_t));
604 src_port = th->src_port;
605 dst_port = th->dst_port;
606 flags = TCP_FLAG_RST;
609 * RFC 793. If the ACK bit is off, sequence number zero is used,
610 * <SEQ=0><ACK=SEG.SEQ+SEG.LEN><CTL=RST,ACK>
611 * If the ACK bit is on,
612 * <SEQ=SEG.ACK><CTL=RST>
616 seq = th->ack_number;
621 flags |= TCP_FLAG_ACK;
622 tmp = clib_net_to_host_u32 (th->seq_number);
623 len = vnet_buffer (b)->tcp.data_len + tcp_is_syn (th) + tcp_is_fin (th);
624 ack = clib_host_to_net_u32 (tmp + len);
628 tcp_reuse_buffer (vm, b);
629 tcp_trajectory_add_start (b, 4);
630 th = vlib_buffer_push_tcp_net_order (b, dst_port, src_port, seq, ack,
631 sizeof (tcp_header_t), flags, 0);
635 ih4 = vlib_buffer_push_ip4 (vm, b, &dst_ip4, &src_ip4,
637 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
642 ih6 = vlib_buffer_push_ip6 (vm, b, &dst_ip6, &src_ip6, IP_PROTOCOL_TCP);
643 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
650 #ifndef CLIB_MARCH_VARIANT
652 * Send reset without reusing existing buffer
654 * It extracts connection info out of original packet
657 tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
658 u32 thread_index, u8 is_ip4)
660 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
661 vlib_main_t *vm = wrk->vm;
663 u32 bi, sw_if_index, fib_index;
664 u8 tcp_hdr_len, flags = 0;
665 tcp_header_t *th, *pkt_th;
667 ip4_header_t *ih4, *pkt_ih4;
668 ip6_header_t *ih6, *pkt_ih6;
669 fib_protocol_t fib_proto;
671 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
674 b = vlib_get_buffer (vm, bi);
675 sw_if_index = vnet_buffer (pkt)->sw_if_index[VLIB_RX];
676 fib_proto = is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
677 fib_index = fib_table_get_index_for_sw_if_index (fib_proto, sw_if_index);
678 tcp_init_buffer (vm, b);
680 /* Make and write options */
681 tcp_hdr_len = sizeof (tcp_header_t);
685 pkt_ih4 = vlib_buffer_get_current (pkt);
686 pkt_th = ip4_next_header (pkt_ih4);
690 pkt_ih6 = vlib_buffer_get_current (pkt);
691 pkt_th = ip6_next_header (pkt_ih6);
694 if (tcp_ack (pkt_th))
696 flags = TCP_FLAG_RST;
697 seq = pkt_th->ack_number;
698 ack = (tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
702 flags = TCP_FLAG_RST | TCP_FLAG_ACK;
704 ack = clib_host_to_net_u32 (vnet_buffer (pkt)->tcp.seq_end);
707 th = vlib_buffer_push_tcp_net_order (b, pkt_th->dst_port, pkt_th->src_port,
708 seq, ack, tcp_hdr_len, flags, 0);
710 /* Swap src and dst ip */
713 ASSERT ((pkt_ih4->ip_version_and_header_length & 0xF0) == 0x40);
714 ih4 = vlib_buffer_push_ip4 (vm, b, &pkt_ih4->dst_address,
715 &pkt_ih4->src_address, IP_PROTOCOL_TCP,
716 tcp_csum_offload (tc));
717 th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih4);
722 ASSERT ((pkt_ih6->ip_version_traffic_class_and_flow_label & 0xF0) ==
724 ih6 = vlib_buffer_push_ip6_custom (vm, b, &pkt_ih6->dst_address,
725 &pkt_ih6->src_address,
727 tc->ipv6_flow_label);
728 th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih6, &bogus);
732 tcp_enqueue_to_ip_lookup (wrk, b, bi, is_ip4, fib_index);
733 TCP_EVT (TCP_EVT_RST_SENT, tc);
734 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
735 TCP_ERROR_RST_SENT, 1);
739 * Build and set reset packet for connection
742 tcp_send_reset (tcp_connection_t * tc)
744 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
745 vlib_main_t *vm = wrk->vm;
749 u16 tcp_hdr_opts_len, advertise_wnd, opts_write_len;
752 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
754 b = vlib_get_buffer (vm, bi);
755 tcp_init_buffer (vm, b);
757 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
758 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
759 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
760 flags = TCP_FLAG_RST;
761 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
762 tc->rcv_nxt, tcp_hdr_opts_len, flags,
764 opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
765 th->checksum = tcp_compute_checksum (tc, b);
766 ASSERT (opts_write_len == tc->snd_opts_len);
767 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
768 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
769 TCP_EVT (TCP_EVT_RST_SENT, tc);
770 vlib_node_increment_counter (vm, tcp_node_index (output, tc->c_is_ip4),
771 TCP_ERROR_RST_SENT, 1);
775 tcp_push_ip_hdr (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
780 vlib_buffer_push_ip4 (wrk->vm, b, &tc->c_lcl_ip4, &tc->c_rmt_ip4,
781 IP_PROTOCOL_TCP, tcp_csum_offload (tc));
785 vlib_buffer_push_ip6_custom (wrk->vm, b, &tc->c_lcl_ip6, &tc->c_rmt_ip6,
786 IP_PROTOCOL_TCP, tc->ipv6_flow_label);
793 * Builds a SYN packet for a half-open connection and sends it to ipx_lookup.
794 * The packet is not forwarded through tcpx_output to avoid doing lookups
795 * in the half_open pool.
798 tcp_send_syn (tcp_connection_t * tc)
800 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
801 vlib_main_t *vm = wrk->vm;
806 * Setup retransmit and establish timers before requesting buffer
807 * such that we can return if we've ran out.
809 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
810 tc->rto * TCP_TO_TIMER_TICK);
812 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
814 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
818 b = vlib_get_buffer (vm, bi);
819 tcp_init_buffer (vm, b);
820 tcp_make_syn (tc, b);
822 /* Measure RTT with this */
823 tc->rtt_ts = tcp_time_now_us (vlib_num_workers ()? 1 : 0);
824 tc->rtt_seq = tc->snd_nxt;
827 tcp_push_ip_hdr (wrk, tc, b);
828 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
829 TCP_EVT (TCP_EVT_SYN_SENT, tc);
833 tcp_send_synack (tcp_connection_t * tc)
835 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
836 vlib_main_t *vm = wrk->vm;
840 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
842 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
844 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
848 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
849 b = vlib_get_buffer (vm, bi);
850 tcp_init_buffer (vm, b);
851 tcp_make_synack (tc, b);
852 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
853 TCP_EVT (TCP_EVT_SYNACK_SENT, tc);
860 tcp_send_fin (tcp_connection_t * tc)
862 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
863 vlib_main_t *vm = wrk->vm;
868 fin_snt = tc->flags & TCP_CONN_FINSNT;
872 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
874 /* Out of buffers so program fin retransmit ASAP */
875 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
879 /* Make sure retransmit retries a fin not data */
880 tc->flags |= TCP_CONN_FINSNT;
884 /* If we have non-dupacks programmed, no need to send them */
885 if ((tc->flags & TCP_CONN_SNDACK) && !tc->pending_dupacks)
886 tc->flags &= ~TCP_CONN_SNDACK;
888 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
889 b = vlib_get_buffer (vm, bi);
890 tcp_init_buffer (vm, b);
891 tcp_make_fin (tc, b);
892 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
893 TCP_EVT (TCP_EVT_FIN_SENT, tc);
894 /* Account for the FIN */
898 tc->flags |= TCP_CONN_FINSNT;
899 tc->flags &= ~TCP_CONN_FINPNDG;
900 tc->snd_una_max = seq_max (tc->snd_una_max, tc->snd_nxt);
905 * Push TCP header and update connection variables. Should only be called
906 * for segments with data, not for 'control' packets.
909 tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b, u32 snd_nxt,
910 u8 compute_opts, u8 maybe_burst, u8 update_snd_nxt)
912 u8 tcp_hdr_opts_len, flags = TCP_FLAG_ACK;
913 u32 advertise_wnd, data_len;
914 tcp_main_t *tm = &tcp_main;
917 data_len = b->current_length;
918 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
919 data_len += b->total_length_not_including_first_buffer;
921 vnet_buffer (b)->tcp.flags = 0;
922 vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
925 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
927 tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
930 advertise_wnd = tc->rcv_wnd >> tc->rcv_wscale;
932 advertise_wnd = tcp_window_to_advertise (tc, TCP_STATE_ESTABLISHED);
934 if (PREDICT_FALSE (tc->flags & TCP_CONN_PSH_PENDING))
936 if (seq_geq (tc->psh_seq, snd_nxt)
937 && seq_lt (tc->psh_seq, snd_nxt + data_len))
938 flags |= TCP_FLAG_PSH;
940 th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, snd_nxt,
941 tc->rcv_nxt, tcp_hdr_opts_len, flags,
946 clib_memcpy_fast ((u8 *) (th + 1),
947 tm->wrk_ctx[tc->c_thread_index].cached_opts,
952 u8 len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
953 ASSERT (len == tc->snd_opts_len);
957 * Update connection variables
961 tc->snd_nxt += data_len;
962 tc->rcv_las = tc->rcv_nxt;
964 tc->bytes_out += data_len;
965 tc->data_segs_out += 1;
967 th->checksum = tcp_compute_checksum (tc, b);
969 TCP_EVT (TCP_EVT_PKTIZE, tc);
973 tcp_buffer_len (vlib_buffer_t * b)
975 u32 data_len = b->current_length;
976 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
977 data_len += b->total_length_not_including_first_buffer;
982 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
984 tcp_connection_t *tc = (tcp_connection_t *) tconn;
986 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
987 tcp_bt_track_tx (tc, tcp_buffer_len (b));
989 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
990 /* update_snd_nxt */ 1);
992 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
993 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
994 /* If not tracking an ACK, start tracking */
995 if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
997 tc->rtt_ts = tcp_time_now_us (tc->c_thread_index);
998 tc->rtt_seq = tc->snd_nxt;
1000 if (PREDICT_FALSE (!tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)))
1002 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1003 tcp_retransmit_timer_set (&wrk->timer_wheel, tc);
1006 tcp_trajectory_add_start (b, 3);
1011 tcp_send_ack (tcp_connection_t * tc)
1013 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1014 vlib_main_t *vm = wrk->vm;
1018 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1020 tcp_update_rcv_wnd (tc);
1023 b = vlib_get_buffer (vm, bi);
1024 tcp_init_buffer (vm, b);
1025 tcp_make_ack (tc, b);
1026 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1030 tcp_program_ack (tcp_connection_t * tc)
1032 if (!(tc->flags & TCP_CONN_SNDACK))
1034 session_add_self_custom_tx_evt (&tc->connection, 1);
1035 tc->flags |= TCP_CONN_SNDACK;
1040 tcp_program_dupack (tcp_connection_t * tc)
1042 if (!(tc->flags & TCP_CONN_SNDACK))
1044 session_add_self_custom_tx_evt (&tc->connection, 1);
1045 tc->flags |= TCP_CONN_SNDACK;
1047 if (tc->pending_dupacks < 255)
1048 tc->pending_dupacks += 1;
1052 tcp_program_retransmit (tcp_connection_t * tc)
1054 if (!(tc->flags & TCP_CONN_RXT_PENDING))
1056 session_add_self_custom_tx_evt (&tc->connection, 0);
1057 tc->flags |= TCP_CONN_RXT_PENDING;
1062 * Delayed ack timer handler
1064 * Sends delayed ACK when timer expires
1067 tcp_timer_delack_handler (tcp_connection_t * tc)
1073 * Send window update ack
1075 * Ensures that it will be sent only once, after a zero rwnd has been
1076 * advertised in a previous ack, and only if rwnd has grown beyond a
1077 * configurable value.
1080 tcp_send_window_update_ack (tcp_connection_t * tc)
1082 if (tcp_zero_rwnd_sent (tc))
1084 tcp_update_rcv_wnd (tc);
1085 if (tc->rcv_wnd >= tcp_cfg.rwnd_min_update_ack * tc->snd_mss)
1087 tcp_zero_rwnd_sent_off (tc);
1088 tcp_program_ack (tc);
1094 * Allocate a new buffer and build a new tcp segment
1096 * @param wrk tcp worker
1097 * @param tc connection for which the segment will be allocated
1098 * @param offset offset of the first byte in the tx fifo
1099 * @param max_deq_byte segment size
1100 * @param[out] b pointer to buffer allocated
1102 * @return the number of bytes in the segment or 0 if buffer cannot be
1103 * allocated or no data available
1106 tcp_prepare_segment (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1107 u32 offset, u32 max_deq_bytes, vlib_buffer_t ** b)
1109 u32 bytes_per_buffer = vnet_get_tcp_main ()->bytes_per_buffer;
1110 vlib_main_t *vm = wrk->vm;
1115 seg_size = max_deq_bytes + TRANSPORT_MAX_HDRS_LEN;
1120 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1123 * Allocate and fill in buffer(s)
1126 /* Easy case, buffer size greater than mss */
1127 if (PREDICT_TRUE (seg_size <= bytes_per_buffer))
1129 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1131 *b = vlib_get_buffer (vm, bi);
1132 data = tcp_init_buffer (vm, *b);
1133 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1135 ASSERT (n_bytes == max_deq_bytes);
1136 b[0]->current_length = n_bytes;
1137 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1138 /* burst */ 0, /* update_snd_nxt */ 0);
1140 /* Split mss into multiple buffers */
1143 u32 chain_bi = ~0, n_bufs_per_seg, n_bufs;
1144 u16 n_peeked, len_to_deq;
1145 vlib_buffer_t *chain_b, *prev_b;
1148 /* Make sure we have enough buffers */
1149 n_bufs_per_seg = ceil ((double) seg_size / bytes_per_buffer);
1150 vec_validate_aligned (wrk->tx_buffers, n_bufs_per_seg - 1,
1151 CLIB_CACHE_LINE_BYTES);
1152 n_bufs = vlib_buffer_alloc (vm, wrk->tx_buffers, n_bufs_per_seg);
1153 if (PREDICT_FALSE (n_bufs != n_bufs_per_seg))
1156 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1160 *b = vlib_get_buffer (vm, wrk->tx_buffers[--n_bufs]);
1161 data = tcp_init_buffer (vm, *b);
1162 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1164 TRANSPORT_MAX_HDRS_LEN);
1165 b[0]->current_length = n_bytes;
1166 b[0]->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
1167 b[0]->total_length_not_including_first_buffer = 0;
1168 max_deq_bytes -= n_bytes;
1171 for (i = 1; i < n_bufs_per_seg; i++)
1174 len_to_deq = clib_min (max_deq_bytes, bytes_per_buffer);
1175 chain_bi = wrk->tx_buffers[--n_bufs];
1176 chain_b = vlib_get_buffer (vm, chain_bi);
1177 chain_b->current_data = 0;
1178 data = vlib_buffer_get_current (chain_b);
1179 n_peeked = session_tx_fifo_peek_bytes (&tc->connection, data,
1182 ASSERT (n_peeked == len_to_deq);
1183 n_bytes += n_peeked;
1184 chain_b->current_length = n_peeked;
1185 chain_b->next_buffer = 0;
1187 /* update previous buffer */
1188 prev_b->next_buffer = chain_bi;
1189 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
1191 max_deq_bytes -= n_peeked;
1192 b[0]->total_length_not_including_first_buffer += n_peeked;
1195 tcp_push_hdr_i (tc, *b, tc->snd_una + offset, /* compute opts */ 0,
1196 /* burst */ 0, /* update_snd_nxt */ 0);
1198 if (PREDICT_FALSE (n_bufs))
1200 clib_warning ("not all buffers consumed");
1201 vlib_buffer_free (vm, wrk->tx_buffers, n_bufs);
1205 ASSERT (n_bytes > 0);
1206 ASSERT (((*b)->current_data + (*b)->current_length) <= bytes_per_buffer);
1212 * Build a retransmit segment
1214 * @return the number of bytes in the segment or 0 if there's nothing to
1218 tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
1219 tcp_connection_t * tc, u32 offset,
1220 u32 max_deq_bytes, vlib_buffer_t ** b)
1222 u32 start, available_bytes;
1225 ASSERT (tc->state >= TCP_STATE_ESTABLISHED);
1226 ASSERT (max_deq_bytes != 0);
1229 * Make sure we can retransmit something
1231 available_bytes = transport_max_tx_dequeue (&tc->connection);
1232 ASSERT (available_bytes >= offset);
1233 available_bytes -= offset;
1234 if (!available_bytes)
1237 max_deq_bytes = clib_min (tc->snd_mss, max_deq_bytes);
1238 max_deq_bytes = clib_min (available_bytes, max_deq_bytes);
1240 start = tc->snd_una + offset;
1241 ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt));
1243 n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b);
1247 tc->snd_rxt_bytes += n_bytes;
1249 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1250 tcp_bt_track_rxt (tc, start, start + n_bytes);
1252 tc->bytes_retrans += n_bytes;
1253 tc->segs_retrans += 1;
1254 tcp_worker_stats_inc (wrk, rxt_segs, 1);
1255 TCP_EVT (TCP_EVT_CC_RTX, tc, offset, n_bytes);
1261 tcp_check_sack_reneging (tcp_connection_t * tc)
1263 sack_scoreboard_t *sb = &tc->sack_sb;
1264 sack_scoreboard_hole_t *hole;
1266 hole = scoreboard_first_hole (sb);
1267 if (!sb->is_reneging && (!hole || hole->start == tc->snd_una))
1270 scoreboard_clear_reneging (sb, tc->snd_una, tc->snd_nxt);
1274 * Reset congestion control, switch cwnd to loss window and try again.
1277 tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
1279 TCP_EVT (TCP_EVT_CC_EVT, tc, 6);
1281 tc->prev_ssthresh = tc->ssthresh;
1282 tc->prev_cwnd = tc->cwnd;
1284 /* If we entrered loss without fast recovery, notify cc algo of the
1285 * congestion event such that it can update ssthresh and its state */
1286 if (!tcp_in_fastrecovery (tc))
1287 tcp_cc_congestion (tc);
1289 /* Let cc algo decide loss cwnd and ssthresh post unrecovered loss */
1293 tc->cwnd_acc_bytes = 0;
1294 tc->tr_occurences += 1;
1295 tcp_recovery_on (tc);
1299 tcp_timer_retransmit_handler (tcp_connection_t * tc)
1301 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1302 vlib_main_t *vm = wrk->vm;
1303 vlib_buffer_t *b = 0;
1306 tcp_worker_stats_inc (wrk, tr_events, 1);
1308 /* Should be handled by a different handler */
1309 if (PREDICT_FALSE (tc->state == TCP_STATE_SYN_SENT))
1312 /* Wait-close and retransmit could pop at the same time */
1313 if (tc->state == TCP_STATE_CLOSED)
1316 if (tc->state >= TCP_STATE_ESTABLISHED)
1318 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1320 /* Lost FIN, retransmit and return */
1321 if (tc->flags & TCP_CONN_FINSNT)
1325 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1329 /* Shouldn't be here. This condition is tricky because it has to take
1330 * into account boff > 0 due to persist timeout. */
1331 if ((tc->rto_boff == 0 && tc->snd_una == tc->snd_nxt)
1332 || (tc->rto_boff > 0 && seq_geq (tc->snd_una, tc->snd_congestion)
1333 && !tcp_flight_size (tc)))
1335 ASSERT (!tcp_in_recovery (tc));
1340 /* We're not in recovery so make sure rto_boff is 0. Can be non 0 due
1341 * to persist timer timeout */
1342 if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
1345 tcp_update_rto (tc);
1348 /* Peer is dead or network connectivity is lost. Close connection.
1349 * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
1350 * a min rto of 0.2s we need to retry about 8 times. */
1351 if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
1353 tcp_send_reset (tc);
1354 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1355 session_transport_closing_notify (&tc->connection);
1356 session_transport_closed_notify (&tc->connection);
1357 tcp_connection_timers_reset (tc);
1358 tcp_program_cleanup (wrk, tc);
1359 tcp_worker_stats_inc (wrk, tr_abort, 1);
1363 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1364 tcp_check_sack_reneging (tc);
1366 /* Update send congestion to make sure that rxt has data to send */
1367 tc->snd_congestion = tc->snd_nxt;
1369 /* Send the first unacked segment. If we're short on buffers, return
1370 * as soon as possible */
1371 n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una);
1372 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b);
1375 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1379 bi = vlib_get_buffer_index (vm, b);
1380 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1382 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1383 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
1386 if (tc->rto_boff == 1)
1388 tcp_cc_init_rxt_timeout (tc);
1389 /* Record timestamp. Eifel detection algorithm RFC3522 */
1390 tc->snd_rxt_ts = tcp_tstamp (tc);
1393 if (tcp_opts_sack_permitted (&tc->rcv_opts))
1394 scoreboard_init_rxt (&tc->sack_sb, tc->snd_una + n_bytes);
1396 tcp_program_retransmit (tc);
1398 /* Retransmit SYN-ACK */
1399 else if (tc->state == TCP_STATE_SYN_RCVD)
1401 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1405 /* Passive open establish timeout */
1406 if (tc->rto > TCP_ESTABLISH_TIME >> 1)
1408 tcp_connection_set_state (tc, TCP_STATE_CLOSED);
1409 tcp_connection_timers_reset (tc);
1410 tcp_program_cleanup (wrk, tc);
1411 tcp_worker_stats_inc (wrk, tr_abort, 1);
1415 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1417 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT, 1);
1422 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1423 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1425 tcp_retransmit_timer_force_update (&wrk->timer_wheel, tc);
1427 b = vlib_get_buffer (vm, bi);
1428 tcp_init_buffer (vm, b);
1429 tcp_make_synack (tc, b);
1430 TCP_EVT (TCP_EVT_SYN_RXT, tc, 1);
1432 /* Retransmit timer already updated, just enqueue to output */
1433 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1437 ASSERT (tc->state == TCP_STATE_CLOSED);
1443 * SYN retransmit timer handler. Active open only.
1446 tcp_timer_retransmit_syn_handler (tcp_connection_t * tc)
1448 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1449 vlib_main_t *vm = wrk->vm;
1450 vlib_buffer_t *b = 0;
1453 /* Note: the connection may have transitioned to ESTABLISHED... */
1454 if (PREDICT_FALSE (tc->state != TCP_STATE_SYN_SENT))
1457 /* Half-open connection actually moved to established but we were
1458 * waiting for syn retransmit to pop to call cleanup from the right
1460 if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
1462 if (tcp_half_open_connection_cleanup (tc))
1463 TCP_DBG ("could not remove half-open connection");
1467 TCP_EVT (TCP_EVT_CC_EVT, tc, 2);
1470 /* Active open establish timeout */
1471 if (tc->rto >= TCP_ESTABLISH_TIME >> 1)
1473 session_stream_connect_notify (&tc->connection, SESSION_E_TIMEDOUT);
1474 tcp_connection_cleanup (tc);
1478 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1480 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN, 1);
1484 /* Try without increasing RTO a number of times. If this fails,
1485 * start growing RTO exponentially */
1487 if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
1488 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1490 b = vlib_get_buffer (vm, bi);
1491 tcp_init_buffer (vm, b);
1492 tcp_make_syn (tc, b);
1494 TCP_EVT (TCP_EVT_SYN_RXT, tc, 0);
1496 /* This goes straight to ipx_lookup */
1497 tcp_push_ip_hdr (wrk, tc, b);
1498 tcp_enqueue_to_ip_lookup (wrk, b, bi, tc->c_is_ip4, tc->c_fib_index);
1500 tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN,
1501 tc->rto * TCP_TO_TIMER_TICK);
1505 * Got 0 snd_wnd from peer, try to do something about it.
1509 tcp_timer_persist_handler (tcp_connection_t * tc)
1511 tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
1512 u32 bi, max_snd_bytes, available_bytes, offset;
1513 tcp_main_t *tm = vnet_get_tcp_main ();
1514 vlib_main_t *vm = wrk->vm;
1519 /* Problem already solved or worse */
1520 if (tc->state == TCP_STATE_CLOSED || tc->snd_wnd > tc->snd_mss
1521 || (tc->flags & TCP_CONN_FINSNT))
1522 goto update_scheduler;
1524 available_bytes = transport_max_tx_dequeue (&tc->connection);
1525 offset = tc->snd_nxt - tc->snd_una;
1527 /* Reprogram persist if no new bytes available to send. We may have data
1529 if (!available_bytes)
1531 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1535 if (available_bytes <= offset)
1536 goto update_scheduler;
1538 /* Increment RTO backoff */
1540 tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
1543 * Try to force the first unsent segment (or buffer)
1545 if (PREDICT_FALSE (!vlib_buffer_alloc (vm, &bi, 1)))
1547 tcp_persist_timer_set (&wrk->timer_wheel, tc);
1551 b = vlib_get_buffer (vm, bi);
1552 data = tcp_init_buffer (vm, b);
1554 tcp_validate_txf_size (tc, offset);
1555 tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
1556 max_snd_bytes = clib_min (tc->snd_mss,
1557 tm->bytes_per_buffer - TRANSPORT_MAX_HDRS_LEN);
1558 n_bytes = session_tx_fifo_peek_bytes (&tc->connection, data, offset,
1560 b->current_length = n_bytes;
1561 ASSERT (n_bytes != 0 && (tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT)
1562 || tc->snd_nxt == tc->snd_una_max
1563 || tc->rto_boff > 1));
1565 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1567 tcp_bt_check_app_limited (tc);
1568 tcp_bt_track_tx (tc, n_bytes);
1571 tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0,
1572 /* burst */ 0, /* update_snd_nxt */ 1);
1573 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1574 tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
1575 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1577 /* Just sent new data, enable retransmit */
1578 tcp_retransmit_timer_update (&wrk->timer_wheel, tc);
1584 if (tcp_is_descheduled (tc))
1585 transport_connection_reschedule (&tc->connection);
1589 * Retransmit first unacked segment
1592 tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
1594 vlib_main_t *vm = wrk->vm;
1598 TCP_EVT (TCP_EVT_CC_EVT, tc, 1);
1600 n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b);
1604 bi = vlib_get_buffer_index (vm, b);
1605 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1611 tcp_transmit_unsent (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1614 u32 offset, n_segs = 0, n_written, bi, available_wnd;
1615 vlib_main_t *vm = wrk->vm;
1616 vlib_buffer_t *b = 0;
1618 offset = tc->snd_nxt - tc->snd_una;
1619 available_wnd = tc->snd_wnd - offset;
1620 burst_size = clib_min (burst_size, available_wnd / tc->snd_mss);
1622 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1623 tcp_bt_check_app_limited (tc);
1625 while (n_segs < burst_size)
1627 n_written = tcp_prepare_segment (wrk, tc, offset, tc->snd_mss, &b);
1631 bi = vlib_get_buffer_index (vm, b);
1632 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1633 offset += n_written;
1636 if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
1637 tcp_bt_track_tx (tc, n_written);
1639 tc->snd_nxt += n_written;
1640 tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
1648 * Estimate send space using proportional rate reduction (RFC6937)
1651 tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc)
1656 pipe = tcp_flight_size (tc);
1657 prr_out = tc->snd_rxt_bytes + (tc->snd_nxt - tc->snd_congestion);
1659 if (pipe > tc->ssthresh)
1661 space = ((int) tc->prr_delivered * ((f64) tc->ssthresh / tc->prev_cwnd))
1667 limit = clib_max ((int) (tc->prr_delivered - prr_out), 0) + tc->snd_mss;
1668 space = clib_min (tc->ssthresh - pipe, limit);
1670 space = clib_max (space, prr_out ? 0 : tc->snd_mss);
1675 tcp_retransmit_should_retry_head (tcp_connection_t * tc,
1676 sack_scoreboard_t * sb)
1678 u32 tx_adv_sack = sb->high_sacked - tc->snd_congestion;
1679 f64 rr = (f64) tc->ssthresh / tc->prev_cwnd;
1681 if (tcp_fastrecovery_first (tc))
1684 return (tx_adv_sack > (tc->snd_una - tc->prr_start) * rr);
1688 tcp_max_tx_deq (tcp_connection_t * tc)
1690 return (transport_max_tx_dequeue (&tc->connection)
1691 - (tc->snd_nxt - tc->snd_una));
1694 #define scoreboard_rescue_rxt_valid(_sb, _tc) \
1695 (seq_geq (_sb->rescue_rxt, _tc->snd_una) \
1696 && seq_leq (_sb->rescue_rxt, _tc->snd_congestion))
1699 * Do retransmit with SACKs
1702 tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1705 u32 n_written = 0, offset, max_bytes, n_segs = 0;
1706 u8 snd_limited = 0, can_rescue = 0;
1707 u32 bi, max_deq, burst_bytes;
1708 sack_scoreboard_hole_t *hole;
1709 vlib_main_t *vm = wrk->vm;
1710 vlib_buffer_t *b = 0;
1711 sack_scoreboard_t *sb;
1714 ASSERT (tcp_in_cong_recovery (tc));
1716 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1717 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1720 tcp_program_retransmit (tc);
1724 if (tcp_in_recovery (tc))
1725 snd_space = tcp_available_cc_snd_space (tc);
1727 snd_space = tcp_fastrecovery_prr_snd_space (tc);
1729 if (snd_space < tc->snd_mss)
1734 /* Check if snd_una is a lost retransmit */
1735 if (pool_elts (sb->holes)
1736 && seq_gt (sb->high_sacked, tc->snd_congestion)
1737 && tc->rxt_head != tc->snd_una
1738 && tcp_retransmit_should_retry_head (tc, sb))
1740 max_bytes = clib_min (tc->snd_mss, tc->snd_congestion - tc->snd_una);
1741 n_written = tcp_prepare_retransmit_segment (wrk, tc, 0, max_bytes, &b);
1744 tcp_program_retransmit (tc);
1747 bi = vlib_get_buffer_index (vm, b);
1748 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1751 tc->rxt_head = tc->snd_una;
1752 tc->rxt_delivered += n_written;
1753 tc->prr_delivered += n_written;
1754 ASSERT (tc->rxt_delivered <= tc->snd_rxt_bytes);
1757 tcp_fastrecovery_first_off (tc);
1759 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1760 hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
1762 max_deq = transport_max_tx_dequeue (&tc->connection);
1763 max_deq -= tc->snd_nxt - tc->snd_una;
1765 while (snd_space > 0 && n_segs < burst_size)
1767 hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue,
1771 /* We are out of lost holes to retransmit so send some new data. */
1772 if (max_deq > tc->snd_mss)
1777 /* Make sure we don't exceed available window and leave space
1778 * for one more packet, to avoid zero window acks */
1779 av_wnd = (int) tc->snd_wnd - (tc->snd_nxt - tc->snd_una);
1780 av_wnd = clib_max (av_wnd - tc->snd_mss, 0);
1781 snd_space = clib_min (snd_space, av_wnd);
1782 snd_space = clib_min (max_deq, snd_space);
1783 burst_size = clib_min (burst_size - n_segs,
1784 snd_space / tc->snd_mss);
1785 burst_size = clib_min (burst_size, TCP_RXT_MAX_BURST);
1786 n_segs_new = tcp_transmit_unsent (wrk, tc, burst_size);
1787 if (max_deq > n_segs_new * tc->snd_mss)
1788 tcp_program_retransmit (tc);
1790 n_segs += n_segs_new;
1794 if (tcp_in_recovery (tc) || !can_rescue
1795 || scoreboard_rescue_rxt_valid (sb, tc))
1798 /* If rescue rxt undefined or less than snd_una then one segment of
1799 * up to SMSS octets that MUST include the highest outstanding
1800 * unSACKed sequence number SHOULD be returned, and RescueRxt set to
1801 * RecoveryPoint. HighRxt MUST NOT be updated.
1803 hole = scoreboard_last_hole (sb);
1804 max_bytes = clib_min (tc->snd_mss, hole->end - hole->start);
1805 max_bytes = clib_min (max_bytes, snd_space);
1806 offset = hole->end - tc->snd_una - max_bytes;
1807 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
1812 sb->rescue_rxt = tc->snd_congestion;
1813 bi = vlib_get_buffer_index (vm, b);
1814 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1819 max_bytes = clib_min (hole->end - sb->high_rxt, snd_space);
1820 max_bytes = snd_limited ? clib_min (max_bytes, tc->snd_mss) : max_bytes;
1824 offset = sb->high_rxt - tc->snd_una;
1825 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1827 ASSERT (n_written <= snd_space);
1829 /* Nothing left to retransmit */
1833 bi = vlib_get_buffer_index (vm, b);
1834 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1836 sb->high_rxt += n_written;
1837 ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt));
1839 snd_space -= n_written;
1844 tcp_program_retransmit (tc);
1848 transport_connection_tx_pacer_reset_bucket (&tc->connection, 0);
1853 * Fast retransmit without SACK info
1856 tcp_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
1859 u32 n_written = 0, offset = 0, bi, max_deq, n_segs_now, max_bytes;
1860 u32 burst_bytes, sent_bytes;
1861 vlib_main_t *vm = wrk->vm;
1862 int snd_space, n_segs = 0;
1866 ASSERT (tcp_in_cong_recovery (tc));
1867 TCP_EVT (TCP_EVT_CC_EVT, tc, 0);
1869 burst_bytes = transport_connection_tx_pacer_burst (&tc->connection);
1870 burst_size = clib_min (burst_size, burst_bytes / tc->snd_mss);
1873 tcp_program_retransmit (tc);
1877 snd_space = tcp_available_cc_snd_space (tc);
1878 cc_limited = snd_space < burst_bytes;
1880 if (!tcp_fastrecovery_first (tc))
1883 /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
1885 while (snd_space > 0 && n_segs < burst_size)
1887 max_bytes = clib_min (tc->snd_mss,
1888 tc->snd_congestion - tc->snd_una - offset);
1891 n_written = tcp_prepare_retransmit_segment (wrk, tc, offset, max_bytes,
1894 /* Nothing left to retransmit */
1898 bi = vlib_get_buffer_index (vm, b);
1899 tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
1900 snd_space -= n_written;
1901 offset += n_written;
1905 if (n_segs == burst_size)
1910 /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
1911 if (snd_space < tc->snd_mss || tc->snd_mss == 0)
1914 max_deq = transport_max_tx_dequeue (&tc->connection);
1915 max_deq -= tc->snd_nxt - tc->snd_una;
1918 snd_space = clib_min (max_deq, snd_space);
1919 burst_size = clib_min (burst_size - n_segs, snd_space / tc->snd_mss);
1920 n_segs_now = tcp_transmit_unsent (wrk, tc, burst_size);
1921 if (n_segs_now && max_deq > n_segs_now * tc->snd_mss)
1922 tcp_program_retransmit (tc);
1923 n_segs += n_segs_now;
1927 tcp_fastrecovery_first_off (tc);
1929 sent_bytes = clib_min (n_segs * tc->snd_mss, burst_bytes);
1930 sent_bytes = cc_limited ? burst_bytes : sent_bytes;
1931 transport_connection_tx_pacer_update_bytes (&tc->connection, sent_bytes);
1937 tcp_send_acks (tcp_connection_t * tc, u32 max_burst_size)
1941 if (!tc->pending_dupacks)
1943 if (tcp_in_cong_recovery (tc) || !tcp_max_tx_deq (tc)
1944 || tc->state != TCP_STATE_ESTABLISHED)
1952 /* If we're supposed to send dupacks but have no ooo data
1953 * send only one ack */
1954 if (!vec_len (tc->snd_sacks))
1957 tc->dupacks_out += 1;
1958 tc->pending_dupacks = 0;
1962 /* Start with first sack block */
1963 tc->snd_sack_pos = 0;
1965 /* Generate enough dupacks to cover all sack blocks. Do not generate
1966 * more sacks than the number of packets received. But do generate at
1967 * least 3, i.e., the number needed to signal congestion, if needed. */
1968 n_acks = vec_len (tc->snd_sacks) / TCP_OPTS_MAX_SACK_BLOCKS;
1969 n_acks = clib_min (n_acks, tc->pending_dupacks);
1970 n_acks = clib_max (n_acks, clib_min (tc->pending_dupacks, 3));
1971 for (j = 0; j < clib_min (n_acks, max_burst_size); j++)
1974 if (n_acks < max_burst_size)
1976 tc->pending_dupacks = 0;
1977 tc->snd_sack_pos = 0;
1978 tc->dupacks_out += n_acks;
1983 TCP_DBG ("constrained by burst size");
1984 tc->pending_dupacks = n_acks - max_burst_size;
1985 tc->dupacks_out += max_burst_size;
1986 tcp_program_dupack (tc);
1987 return max_burst_size;
1992 tcp_do_retransmit (tcp_connection_t * tc, u32 max_burst_size)
1994 tcp_worker_ctx_t *wrk;
1997 if (PREDICT_FALSE (tc->state == TCP_STATE_CLOSED))
2000 wrk = tcp_get_worker (tc->c_thread_index);
2002 if (tcp_opts_sack_permitted (&tc->rcv_opts))
2003 n_segs = tcp_retransmit_sack (wrk, tc, max_burst_size);
2005 n_segs = tcp_retransmit_no_sack (wrk, tc, max_burst_size);
2011 tcp_session_custom_tx (void *conn, transport_send_params_t * sp)
2013 tcp_connection_t *tc = (tcp_connection_t *) conn;
2016 if (tcp_in_cong_recovery (tc) && (tc->flags & TCP_CONN_RXT_PENDING))
2018 tc->flags &= ~TCP_CONN_RXT_PENDING;
2019 n_segs = tcp_do_retransmit (tc, sp->max_burst_size);
2022 if (!(tc->flags & TCP_CONN_SNDACK))
2025 tc->flags &= ~TCP_CONN_SNDACK;
2027 /* We have retransmitted packets and no dupack */
2028 if (n_segs && !tc->pending_dupacks)
2031 if (sp->max_burst_size <= n_segs)
2033 tcp_program_ack (tc);
2037 n_segs += tcp_send_acks (tc, sp->max_burst_size - n_segs);
2041 #endif /* CLIB_MARCH_VARIANT */
2044 tcp_output_handle_link_local (tcp_connection_t * tc0, vlib_buffer_t * b0,
2045 u16 * next0, u32 * error0)
2047 ip_adjacency_t *adj;
2050 /* Not thread safe but as long as the connection exists the adj should
2052 ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &tc0->c_rmt_ip,
2054 if (ai == ADJ_INDEX_INVALID)
2056 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2057 *next0 = TCP_OUTPUT_NEXT_DROP;
2058 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2063 if (PREDICT_TRUE (adj->lookup_next_index == IP_LOOKUP_NEXT_REWRITE))
2064 *next0 = TCP_OUTPUT_NEXT_IP_REWRITE;
2065 else if (adj->lookup_next_index == IP_LOOKUP_NEXT_ARP)
2066 *next0 = TCP_OUTPUT_NEXT_IP_ARP;
2069 *next0 = TCP_OUTPUT_NEXT_DROP;
2070 *error0 = TCP_ERROR_LINK_LOCAL_RW;
2072 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ai;
2076 tcp46_output_trace_frame (vlib_main_t * vm, vlib_node_runtime_t * node,
2077 u32 * to_next, u32 n_bufs)
2079 tcp_connection_t *tc;
2085 for (i = 0; i < n_bufs; i++)
2087 b = vlib_get_buffer (vm, to_next[i]);
2088 if (!(b->flags & VLIB_BUFFER_IS_TRACED))
2090 th = vlib_buffer_get_current (b);
2091 tc = tcp_connection_get (vnet_buffer (b)->tcp.connection_index,
2093 t = vlib_add_trace (vm, node, b, sizeof (*t));
2094 clib_memcpy_fast (&t->tcp_header, th, sizeof (t->tcp_header));
2095 clib_memcpy_fast (&t->tcp_connection, tc, sizeof (t->tcp_connection));
2100 tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
2101 tcp_connection_t * tc0, u8 is_ip4)
2103 TCP_EVT (TCP_EVT_OUTPUT, tc0,
2104 ((tcp_header_t *) vlib_buffer_get_current (b0))->flags,
2105 b0->current_length);
2108 vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4, &tc0->c_rmt_ip4,
2109 IP_PROTOCOL_TCP, tcp_csum_offload (tc0));
2111 vlib_buffer_push_ip6_custom (vm, b0, &tc0->c_lcl_ip6, &tc0->c_rmt_ip6,
2112 IP_PROTOCOL_TCP, tc0->ipv6_flow_label);
2116 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
2118 if (PREDICT_TRUE (!(tc->cfg_flags & TCP_CFG_F_TSO)))
2121 u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
2123 if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
2124 data_len += b->total_length_not_including_first_buffer;
2126 if (PREDICT_TRUE (data_len <= tc->snd_mss))
2130 ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
2131 ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);
2132 b->flags |= VNET_BUFFER_F_GSO;
2133 vnet_buffer2 (b)->gso_l4_hdr_sz =
2134 sizeof (tcp_header_t) + tc->snd_opts_len;
2135 vnet_buffer2 (b)->gso_size = tc->snd_mss;
2140 tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
2141 vlib_node_runtime_t * error_node, u16 * next0,
2144 /* If next_index is not drop use it */
2145 if (tc0->next_node_index)
2147 *next0 = tc0->next_node_index;
2148 vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
2152 *next0 = TCP_OUTPUT_NEXT_IP_LOOKUP;
2155 vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
2156 vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
2162 if (PREDICT_FALSE (ip6_address_is_link_local_unicast (&tc0->c_rmt_ip6)))
2163 tcp_output_handle_link_local (tc0, b0, next0, &error0);
2165 if (PREDICT_FALSE (error0))
2167 b0->error = error_node->errors[error0];
2176 tcp46_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2177 vlib_frame_t * frame, int is_ip4)
2179 u32 n_left_from, *from, thread_index = vm->thread_index;
2180 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2181 u16 nexts[VLIB_FRAME_SIZE], *next;
2183 from = vlib_frame_vector_args (frame);
2184 n_left_from = frame->n_vectors;
2185 tcp_set_time_now (tcp_get_worker (thread_index));
2187 if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
2188 tcp46_output_trace_frame (vm, node, from, n_left_from);
2190 vlib_get_buffers (vm, from, bufs, n_left_from);
2194 while (n_left_from >= 4)
2196 tcp_connection_t *tc0, *tc1;
2199 vlib_prefetch_buffer_header (b[2], STORE);
2200 CLIB_PREFETCH (b[2]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2202 vlib_prefetch_buffer_header (b[3], STORE);
2203 CLIB_PREFETCH (b[3]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2206 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2208 tc1 = tcp_connection_get (vnet_buffer (b[1])->tcp.connection_index,
2211 if (PREDICT_TRUE (!tc0 + !tc1 == 0))
2213 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2214 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2216 tcp_check_if_gso (tc0, b[0]);
2217 tcp_check_if_gso (tc1, b[1]);
2219 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2220 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2226 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2227 tcp_check_if_gso (tc0, b[0]);
2228 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2232 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2233 next[0] = TCP_OUTPUT_NEXT_DROP;
2237 tcp_output_push_ip (vm, b[1], tc1, is_ip4);
2238 tcp_check_if_gso (tc1, b[1]);
2239 tcp_output_handle_packet (tc1, b[1], node, &next[1], is_ip4);
2243 b[1]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2244 next[1] = TCP_OUTPUT_NEXT_DROP;
2252 while (n_left_from > 0)
2254 tcp_connection_t *tc0;
2256 if (n_left_from > 1)
2258 vlib_prefetch_buffer_header (b[1], STORE);
2259 CLIB_PREFETCH (b[1]->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
2262 tc0 = tcp_connection_get (vnet_buffer (b[0])->tcp.connection_index,
2265 if (PREDICT_TRUE (tc0 != 0))
2267 tcp_output_push_ip (vm, b[0], tc0, is_ip4);
2268 tcp_check_if_gso (tc0, b[0]);
2269 tcp_output_handle_packet (tc0, b[0], node, &next[0], is_ip4);
2273 b[0]->error = node->errors[TCP_ERROR_INVALID_CONNECTION];
2274 next[0] = TCP_OUTPUT_NEXT_DROP;
2282 vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2283 vlib_node_increment_counter (vm, tcp_node_index (output, is_ip4),
2284 TCP_ERROR_PKTS_SENT, frame->n_vectors);
2285 return frame->n_vectors;
2288 VLIB_NODE_FN (tcp4_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2289 vlib_frame_t * from_frame)
2291 return tcp46_output_inline (vm, node, from_frame, 1 /* is_ip4 */ );
2294 VLIB_NODE_FN (tcp6_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2295 vlib_frame_t * from_frame)
2297 return tcp46_output_inline (vm, node, from_frame, 0 /* is_ip4 */ );
2301 VLIB_REGISTER_NODE (tcp4_output_node) =
2303 .name = "tcp4-output",
2304 /* Takes a vector of packets. */
2305 .vector_size = sizeof (u32),
2306 .n_errors = TCP_N_ERROR,
2307 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2308 .error_strings = tcp_error_strings,
2309 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2311 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2312 foreach_tcp4_output_next
2315 .format_buffer = format_tcp_header,
2316 .format_trace = format_tcp_tx_trace,
2321 VLIB_REGISTER_NODE (tcp6_output_node) =
2323 .name = "tcp6-output",
2324 /* Takes a vector of packets. */
2325 .vector_size = sizeof (u32),
2326 .n_errors = TCP_N_ERROR,
2327 .protocol_hint = VLIB_NODE_PROTO_HINT_TCP,
2328 .error_strings = tcp_error_strings,
2329 .n_next_nodes = TCP_OUTPUT_N_NEXT,
2331 #define _(s,n) [TCP_OUTPUT_NEXT_##s] = n,
2332 foreach_tcp6_output_next
2335 .format_buffer = format_tcp_header,
2336 .format_trace = format_tcp_tx_trace,
2340 typedef enum _tcp_reset_next
2342 TCP_RESET_NEXT_DROP,
2343 TCP_RESET_NEXT_IP_LOOKUP,
2347 #define foreach_tcp4_reset_next \
2348 _(DROP, "error-drop") \
2349 _(IP_LOOKUP, "ip4-lookup")
2351 #define foreach_tcp6_reset_next \
2352 _(DROP, "error-drop") \
2353 _(IP_LOOKUP, "ip6-lookup")
2356 tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
2357 vlib_frame_t * from_frame, u8 is_ip4)
2359 u32 error0 = TCP_ERROR_RST_SENT, next0 = TCP_RESET_NEXT_IP_LOOKUP;
2360 u32 n_left_from, next_index, *from, *to_next;
2362 from = vlib_frame_vector_args (from_frame);
2363 n_left_from = from_frame->n_vectors;
2365 next_index = node->cached_next_index;
2367 while (n_left_from > 0)
2371 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
2373 while (n_left_from > 0 && n_left_to_next > 0)
2385 n_left_to_next -= 1;
2387 b0 = vlib_get_buffer (vm, bi0);
2388 tcp_make_reset_in_place (vm, b0, is_ip4);
2390 /* Prepare to send to IP lookup */
2391 vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
2393 b0->error = node->errors[error0];
2394 b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
2395 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
2397 th0 = vlib_buffer_get_current (b0);
2399 th0 = ip4_next_header ((ip4_header_t *) th0);
2401 th0 = ip6_next_header ((ip6_header_t *) th0);
2402 t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
2403 clib_memcpy_fast (&t0->tcp_header, th0,
2404 sizeof (t0->tcp_header));
2407 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
2408 n_left_to_next, bi0, next0);
2410 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
2412 return from_frame->n_vectors;
2415 VLIB_NODE_FN (tcp4_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2416 vlib_frame_t * from_frame)
2418 return tcp46_send_reset_inline (vm, node, from_frame, 1);
2421 VLIB_NODE_FN (tcp6_reset_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2422 vlib_frame_t * from_frame)
2424 return tcp46_send_reset_inline (vm, node, from_frame, 0);
2428 VLIB_REGISTER_NODE (tcp4_reset_node) = {
2429 .name = "tcp4-reset",
2430 .vector_size = sizeof (u32),
2431 .n_errors = TCP_N_ERROR,
2432 .error_strings = tcp_error_strings,
2433 .n_next_nodes = TCP_RESET_N_NEXT,
2435 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2436 foreach_tcp4_reset_next
2439 .format_trace = format_tcp_tx_trace,
2444 VLIB_REGISTER_NODE (tcp6_reset_node) = {
2445 .name = "tcp6-reset",
2446 .vector_size = sizeof (u32),
2447 .n_errors = TCP_N_ERROR,
2448 .error_strings = tcp_error_strings,
2449 .n_next_nodes = TCP_RESET_N_NEXT,
2451 #define _(s,n) [TCP_RESET_NEXT_##s] = n,
2452 foreach_tcp6_reset_next
2455 .format_trace = format_tcp_tx_trace,
2460 * fd.io coding-style-patch-verification: ON
2463 * eval: (c-set-style "gnu")