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.
19 #include <vnet/vnet.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/tcp/tcp_packet.h>
22 #include <vnet/tcp/tcp_timer.h>
23 #include <vnet/session/transport.h>
24 #include <vnet/session/session.h>
25 #include <vnet/tcp/tcp_debug.h>
27 #define TCP_TICK 0.001 /**< TCP tick period (s) */
28 #define THZ (u32) (1/TCP_TICK) /**< TCP tick frequency */
29 #define TCP_TSTAMP_RESOLUTION TCP_TICK /**< Time stamp resolution */
30 #define TCP_PAWS_IDLE 24 * 24 * 60 * 60 * THZ /**< 24 days */
31 #define TCP_FIB_RECHECK_PERIOD 1 * THZ /**< Recheck every 1s */
32 #define TCP_MAX_OPTION_SPACE 40
33 #define TCP_CC_DATA_SZ 24
34 #define TCP_MAX_GSO_SZ 65536
35 #define TCP_RXT_MAX_BURST 10
37 #define TCP_DUPACK_THRESHOLD 3
38 #define TCP_IW_N_SEGMENTS 10
39 #define TCP_ALWAYS_ACK 1 /**< On/off delayed acks */
40 #define TCP_USE_SACKS 1 /**< Disable only for testing */
42 /** TCP FSM state definitions as per RFC793. */
43 #define foreach_tcp_fsm_state \
46 _(SYN_SENT, "SYN_SENT") \
47 _(SYN_RCVD, "SYN_RCVD") \
48 _(ESTABLISHED, "ESTABLISHED") \
49 _(CLOSE_WAIT, "CLOSE_WAIT") \
50 _(FIN_WAIT_1, "FIN_WAIT_1") \
51 _(LAST_ACK, "LAST_ACK") \
52 _(CLOSING, "CLOSING") \
53 _(FIN_WAIT_2, "FIN_WAIT_2") \
54 _(TIME_WAIT, "TIME_WAIT")
56 typedef enum _tcp_state
58 #define _(sym, str) TCP_STATE_##sym,
64 format_function_t format_tcp_state;
65 format_function_t format_tcp_flags;
66 format_function_t format_tcp_sacks;
67 format_function_t format_tcp_rcv_sacks;
70 #define foreach_tcp_timer \
71 _(RETRANSMIT, "RETRANSMIT") \
72 _(DELACK, "DELAYED ACK") \
73 _(PERSIST, "PERSIST") \
74 _(WAITCLOSE, "WAIT CLOSE") \
75 _(RETRANSMIT_SYN, "RETRANSMIT SYN") \
77 typedef enum _tcp_timers
79 #define _(sym, str) TCP_TIMER_##sym,
85 #define TCP_TIMER_HANDLE_INVALID ((u32) ~0)
87 #define TCP_TIMER_TICK 0.1 /**< Timer tick in seconds */
88 #define TCP_TO_TIMER_TICK TCP_TICK*10 /**< Factor for converting
89 ticks to timer ticks */
91 #define TCP_RTO_MAX 60 * THZ /* Min max RTO (60s) as per RFC6298 */
92 #define TCP_RTO_MIN 0.2 * THZ /* Min RTO (200ms) - lower than standard */
93 #define TCP_RTT_MAX 30 * THZ /* 30s (probably too much) */
94 #define TCP_RTO_SYN_RETRIES 3 /* SYN retries without doubling RTO */
95 #define TCP_RTO_INIT 1 * THZ /* Initial retransmit timer */
96 #define TCP_RTO_BOFF_MAX 8 /* Max number of retries before reset */
97 #define TCP_ESTABLISH_TIME (60 * THZ) /* Connection establish timeout */
99 /** Connection configuration flags */
100 #define foreach_tcp_cfg_flag \
101 _(RATE_SAMPLE, "Rate sampling") \
102 _(NO_CSUM_OFFLOAD, "No csum offload") \
103 _(NO_TSO, "TSO off") \
105 _(NO_ENDPOINT,"No endpoint") \
107 typedef enum tcp_cfg_flag_bits_
109 #define _(sym, str) TCP_CFG_F_##sym##_BIT,
113 } tcp_cfg_flag_bits_e;
115 typedef enum tcp_cfg_flag_
117 #define _(sym, str) TCP_CFG_F_##sym = 1 << TCP_CFG_F_##sym##_BIT,
123 /** TCP connection flags */
124 #define foreach_tcp_connection_flag \
125 _(SNDACK, "Send ACK") \
126 _(FINSNT, "FIN sent") \
127 _(RECOVERY, "Recovery") \
128 _(FAST_RECOVERY, "Fast Recovery") \
129 _(DCNT_PENDING, "Disconnect pending") \
130 _(HALF_OPEN_DONE, "Half-open completed") \
131 _(FINPNDG, "FIN pending") \
132 _(RXT_PENDING, "Retransmit pending") \
133 _(FRXT_FIRST, "Retransmit first") \
134 _(DEQ_PENDING, "Dequeue pending ") \
135 _(PSH_PENDING, "PSH pending") \
136 _(FINRCVD, "FIN received") \
137 _(ZERO_RWND_SENT, "Zero RWND sent") \
139 typedef enum tcp_connection_flag_bits_
141 #define _(sym, str) TCP_CONN_##sym##_BIT,
142 foreach_tcp_connection_flag
145 } tcp_connection_flag_bits_e;
147 typedef enum tcp_connection_flag_
149 #define _(sym, str) TCP_CONN_##sym = 1 << TCP_CONN_##sym##_BIT,
150 foreach_tcp_connection_flag
153 } tcp_connection_flags_e;
155 #define TCP_SCOREBOARD_TRACE (0)
156 #define TCP_MAX_SACK_BLOCKS 256 /**< Max number of SACK blocks stored */
157 #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0)
159 typedef struct _scoreboard_trace_elt
166 } scoreboard_trace_elt_t;
168 typedef struct _sack_scoreboard_hole
170 u32 next; /**< Index for next entry in linked list */
171 u32 prev; /**< Index for previous entry in linked list */
172 u32 start; /**< Start sequence number */
173 u32 end; /**< End sequence number */
174 u8 is_lost; /**< Mark hole as lost */
175 } sack_scoreboard_hole_t;
177 typedef struct _sack_scoreboard
179 sack_scoreboard_hole_t *holes; /**< Pool of holes */
180 u32 head; /**< Index of first entry */
181 u32 tail; /**< Index of last entry */
182 u32 sacked_bytes; /**< Number of bytes sacked in sb */
183 u32 last_sacked_bytes; /**< Number of bytes last sacked */
184 u32 last_bytes_delivered; /**< Sack bytes delivered to app */
185 u32 rxt_sacked; /**< Rxt bytes last delivered */
186 u32 high_sacked; /**< Highest byte sacked (fack) */
187 u32 high_rxt; /**< Highest retransmitted sequence */
188 u32 rescue_rxt; /**< Rescue sequence number */
189 u32 lost_bytes; /**< Bytes lost as per RFC6675 */
190 u32 last_lost_bytes; /**< Number of bytes last lost */
191 u32 cur_rxt_hole; /**< Retransmitting from this hole */
194 #if TCP_SCOREBOARD_TRACE
195 scoreboard_trace_elt_t *trace;
200 #if TCP_SCOREBOARD_TRACE
201 #define tcp_scoreboard_trace_add(_tc, _ack) \
203 static u64 _group = 0; \
204 sack_scoreboard_t *_sb = &_tc->sack_sb; \
205 sack_block_t *_sack, *_sacks; \
206 scoreboard_trace_elt_t *_elt; \
209 _sacks = _tc->rcv_opts.sacks; \
210 for (i = 0; i < vec_len (_sacks); i++) \
212 _sack = &_sacks[i]; \
213 vec_add2 (_sb->trace, _elt, 1); \
214 _elt->start = _sack->start; \
215 _elt->end = _sack->end; \
216 _elt->ack = _elt->end == _ack ? _ack : 0; \
217 _elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0; \
218 _elt->group = _group; \
222 #define tcp_scoreboard_trace_add(_tc, _ack)
225 sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
226 sack_scoreboard_hole_t *
227 start, u8 have_sent_1_smss,
230 sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
233 sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
234 sack_scoreboard_hole_t * hole);
235 sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
236 sack_scoreboard_hole_t * hole);
237 sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
238 sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
240 void scoreboard_clear (sack_scoreboard_t * sb);
241 void scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end);
242 void scoreboard_init (sack_scoreboard_t * sb);
243 void scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una);
244 u8 *format_tcp_scoreboard (u8 * s, va_list * args);
246 #define TCP_BTS_INVALID_INDEX ((u32)~0)
248 typedef enum tcp_bts_flags_
251 TCP_BTS_IS_APP_LIMITED = 1 << 1,
252 TCP_BTS_IS_SACKED = 1 << 2,
253 TCP_BTS_IS_RXT_LOST = 1 << 3,
254 } __clib_packed tcp_bts_flags_t;
256 typedef struct tcp_bt_sample_
258 u32 next; /**< Next sample index in list */
259 u32 prev; /**< Previous sample index in list */
260 u32 min_seq; /**< Min seq number in sample */
261 u32 max_seq; /**< Max seq number. Set for rxt samples */
262 u64 delivered; /**< Total delivered bytes for sample */
263 f64 delivered_time; /**< Delivered time when sample taken */
264 f64 tx_time; /**< Transmit time for the burst */
265 f64 first_tx_time; /**< Connection first tx time at tx */
266 tcp_bts_flags_t flags; /**< Sample flag */
269 typedef struct tcp_rate_sample_
271 u64 prior_delivered; /**< Delivered of sample used for rate, i.e.,
272 total bytes delivered at prior_time */
273 f64 prior_time; /**< Delivered time of sample used for rate */
274 f64 interval_time; /**< Time to ack the bytes delivered */
275 f64 rtt_time; /**< RTT for sample */
276 u32 delivered; /**< Bytes delivered in interval_time */
277 u32 acked_and_sacked; /**< Bytes acked + sacked now */
278 u32 lost; /**< Bytes lost now */
279 tcp_bts_flags_t flags; /**< Rate sample flags from bt sample */
282 typedef struct tcp_byte_tracker_
284 tcp_bt_sample_t *samples; /**< Pool of samples */
285 rb_tree_t sample_lookup; /**< Rbtree for sample lookup by min_seq */
286 u32 head; /**< Head of samples linked list */
287 u32 tail; /**< Tail of samples linked list */
288 u32 last_ooo; /**< Cached last ooo sample */
289 } tcp_byte_tracker_t;
291 typedef enum _tcp_cc_algorithm_type
295 TCP_CC_LAST = TCP_CC_CUBIC
296 } tcp_cc_algorithm_type_e;
298 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
300 typedef enum _tcp_cc_ack_t
307 typedef enum tcp_cc_event_
313 * As per RFC4898 tcpEStatsStackSoftErrors
315 typedef struct tcp_errors_
317 u32 below_data_wnd; /**< All data in seg is below snd_una */
318 u32 above_data_wnd; /**< Some data in segment is above snd_wnd */
319 u32 below_ack_wnd; /**< Acks for data below snd_una */
320 u32 above_ack_wnd; /**< Acks for data not sent */
323 typedef struct _tcp_connection
325 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
326 transport_connection_t connection; /**< Common transport data. First! */
328 u8 state; /**< TCP state as per tcp_state_t */
329 u8 cfg_flags; /**< Connection configuration flags */
330 u16 flags; /**< Connection flags (see tcp_conn_flags_e) */
331 u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */
333 u64 segs_in; /** RFC4022/4898 tcpHCInSegs/tcpEStatsPerfSegsIn */
334 u64 bytes_in; /** RFC4898 tcpEStatsPerfHCDataOctetsIn */
335 u64 segs_out; /** RFC4898 tcpEStatsPerfSegsOut */
336 u64 bytes_out; /** RFC4898 tcpEStatsPerfHCDataOctetsOut */
338 /** Send sequence variables RFC793 */
339 u32 snd_una; /**< oldest unacknowledged sequence number */
340 u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/
341 u32 snd_wnd; /**< send window */
342 u32 snd_wl1; /**< seq number used for last snd.wnd update */
343 u32 snd_wl2; /**< ack number used for last snd.wnd update */
344 u32 snd_nxt; /**< next seq number to be sent */
345 u16 snd_mss; /**< Effective send max seg (data) size */
347 u64 data_segs_in; /** RFC4898 tcpEStatsPerfDataSegsIn */
348 u64 data_segs_out; /** RFC4898 tcpEStatsPerfDataSegsOut */
350 /** Receive sequence variables RFC793 */
351 u32 rcv_nxt; /**< next sequence number expected */
352 u32 rcv_wnd; /**< receive window we expect */
354 u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */
355 u32 iss; /**< initial sent sequence */
356 u32 irs; /**< initial remote sequence */
359 u8 snd_opts_len; /**< Tx options len */
360 u8 rcv_wscale; /**< Window scale to advertise to peer */
361 u8 snd_wscale; /**< Window scale to use when sending */
362 u32 tsval_recent; /**< Last timestamp received */
363 u32 tsval_recent_age; /**< When last updated tstamp_recent*/
364 tcp_options_t snd_opts; /**< Tx options for connection */
365 tcp_options_t rcv_opts; /**< Rx options for connection */
367 sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */
368 u8 snd_sack_pos; /**< Position in vec of first block to send */
369 sack_block_t *snd_sacks_fl; /**< Vector for building new list */
370 sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */
372 u16 rcv_dupacks; /**< Number of recent DUPACKs received */
373 u32 dupacks_in; /**< RFC4898 tcpEStatsStackDupAcksIn*/
374 u8 pending_dupacks; /**< Number of DUPACKs to be sent */
375 u32 dupacks_out; /**< RFC4898 tcpEStatsPathDupAcksOut */
377 /* Congestion control */
378 u32 cwnd; /**< Congestion window */
379 u32 cwnd_acc_bytes; /**< Bytes accumulated for cwnd increment */
380 u32 ssthresh; /**< Slow-start threshold */
381 u32 prev_ssthresh; /**< ssthresh before congestion */
382 u32 prev_cwnd; /**< ssthresh before congestion */
383 u32 bytes_acked; /**< Bytes acknowledged by current segment */
384 u32 burst_acked; /**< Bytes acknowledged in current burst */
385 u32 snd_rxt_bytes; /**< Retransmitted bytes during current cc event */
386 u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
387 u32 prr_delivered; /**< RFC6937 bytes delivered during current event */
388 u32 prr_start; /**< snd_una when prr starts */
389 u32 rxt_delivered; /**< Rxt bytes delivered during current cc event */
390 u32 rxt_head; /**< snd_una last time we re rxted the head */
391 u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
392 u32 snd_congestion; /**< snd_una_max when congestion is detected */
393 u32 tx_fifo_size; /**< Tx fifo size. Used to constrain cwnd */
394 tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
395 u8 cc_data[TCP_CC_DATA_SZ]; /**< Congestion control algo private data */
397 u32 fr_occurences; /**< fast-retransmit occurrences RFC4898
398 tcpEStatsStackFastRetran */
399 u32 tr_occurences; /**< timer-retransmit occurrences */
400 u64 bytes_retrans; /**< RFC4898 tcpEStatsPerfOctetsRetrans */
401 u64 segs_retrans; /**< RFC4898 tcpEStatsPerfSegsRetrans*/
404 u32 rto; /**< Retransmission timeout */
405 u32 rto_boff; /**< Index for RTO backoff */
406 u32 srtt; /**< Smoothed RTT */
407 u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */
408 u32 rtt_seq; /**< Sequence number for tracked ACK */
409 f64 rtt_ts; /**< Timestamp for tracked ACK */
410 f64 mrtt_us; /**< High precision mrtt from tracked acks */
412 u32 psh_seq; /**< Add psh header for seg that includes this */
413 u32 next_node_index; /**< Can be used to control next node in output */
414 u32 next_node_opaque; /**< Opaque to pass to next node */
415 u32 limited_transmit; /**< snd_nxt when limited transmit starts */
416 u32 sw_if_index; /**< Interface for the connection */
418 /* Delivery rate estimation */
419 u64 delivered; /**< Total bytes delivered to peer */
420 u64 app_limited; /**< Delivered when app-limited detected */
421 f64 delivered_time; /**< Time last bytes were acked */
422 f64 first_tx_time; /**< Send time for recently delivered/sent */
423 tcp_byte_tracker_t *bt; /**< Tx byte tracker */
425 tcp_errors_t errors; /**< Soft connection errors */
427 f64 start_ts; /**< Timestamp when connection initialized */
428 u32 last_fib_check; /**< Last time we checked fib route for peer */
429 u16 mss; /**< Our max seg size that includes options */
430 u32 timestamp_delta; /**< Offset for timestamp */
431 u32 ipv6_flow_label; /**< flow label for ipv6 header */
433 #define rst_state snd_wl1
437 struct _tcp_cc_algorithm
440 uword (*unformat_cfg) (unformat_input_t * input);
441 void (*init) (tcp_connection_t * tc);
442 void (*cleanup) (tcp_connection_t * tc);
443 void (*rcv_ack) (tcp_connection_t * tc, tcp_rate_sample_t *rs);
444 void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack,
445 tcp_rate_sample_t *rs);
446 void (*congestion) (tcp_connection_t * tc);
447 void (*loss) (tcp_connection_t * tc);
448 void (*recovered) (tcp_connection_t * tc);
449 void (*undo_recovery) (tcp_connection_t * tc);
450 void (*event) (tcp_connection_t *tc, tcp_cc_event_t evt);
451 u64 (*get_pacing_rate) (tcp_connection_t *tc);
455 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
456 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
457 #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY
458 #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY
459 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
460 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
461 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
462 #define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
463 #define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
464 #define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
465 #define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
466 #define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
467 #define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
469 #define tcp_in_cong_recovery(tc) ((tc)->flags & \
470 (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
472 #define tcp_csum_offload(tc) (!((tc)->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
474 typedef void (timer_expiration_handler) (tcp_connection_t * tc);
476 extern timer_expiration_handler tcp_timer_delack_handler;
477 extern timer_expiration_handler tcp_timer_retransmit_handler;
478 extern timer_expiration_handler tcp_timer_persist_handler;
479 extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
482 tcp_cong_recovery_off (tcp_connection_t * tc)
484 tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
485 tcp_fastrecovery_first_off (tc);
488 #define tcp_zero_rwnd_sent(tc) ((tc)->flags & TCP_CONN_ZERO_RWND_SENT)
489 #define tcp_zero_rwnd_sent_on(tc) (tc)->flags |= TCP_CONN_ZERO_RWND_SENT
490 #define tcp_zero_rwnd_sent_off(tc) (tc)->flags &= ~TCP_CONN_ZERO_RWND_SENT
492 typedef enum _tcp_error
494 #define tcp_error(n,s) TCP_ERROR_##n,
495 #include <vnet/tcp/tcp_error.def>
500 typedef struct _tcp_lookup_dispatch
503 } tcp_lookup_dispatch_t;
505 #define foreach_tcp_wrk_stat \
506 _(timer_expirations, u64, "timer expirations") \
507 _(rxt_segs, u64, "segments retransmitted") \
508 _(tr_events, u32, "timer retransmit events") \
509 _(to_closewait, u32, "timeout close-wait") \
510 _(to_closewait2, u32, "timeout close-wait w/data") \
511 _(to_finwait1, u32, "timeout fin-wait-1") \
512 _(to_finwait2, u32, "timeout fin-wait-2") \
513 _(to_lastack, u32, "timeout last-ack") \
514 _(to_closing, u32, "timeout closing") \
515 _(tr_abort, u32, "timer retransmit abort") \
516 _(rst_unread, u32, "reset on close due to unread data") \
518 typedef struct tcp_wrk_stats_
520 #define _(name, type, str) type name;
525 typedef struct tcp_free_req_
527 clib_time_type_t free_time;
528 u32 connection_index;
531 typedef struct tcp_worker_ctx_
533 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
535 /** worker's pool of connections */
536 tcp_connection_t *connections;
538 /** vector of pending ack dequeues */
539 u32 *pending_deq_acked;
541 /** vector of pending disconnect notifications */
542 u32 *pending_disconnects;
544 /** vector of pending reset notifications */
547 /** convenience pointer to this thread's vlib main */
553 /* Max timers to be handled per dispatch loop */
554 u32 max_timers_per_loop;
556 /** tx frames for ip 4/6 lookup nodes */
557 vlib_frame_t *ip_lookup_tx_frames[2];
559 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
561 /** cached 'on the wire' options for bursts */
564 /** tx buffer free list */
567 /* Fifo of pending timer expirations */
570 /* fifo of pending free requests */
571 tcp_cleanup_req_t *pending_cleanups;
573 /** worker timer wheel */
574 tw_timer_wheel_16t_2w_512sl_t timer_wheel;
576 CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
578 tcp_wrk_stats_t stats;
581 #define tcp_worker_stats_inc(_ti,_stat,_val) \
582 tcp_main.wrk_ctx[_ti].stats._stat += _val
584 #define tcp_workerp_stats_inc(_wrk,_stat,_val) \
585 _wrk->stats._stat += _val
587 typedef struct tcp_iss_seed_
593 typedef struct tcp_configuration_
595 /** Max rx fifo size for a session (in bytes). It is used in to compute the
596 * rfc 7323 window scaling factor */
599 /** Min rx fifo for a session (in bytes) */
602 /** Default MTU to be used when establishing connections */
605 /** Initial CWND multiplier, which multiplies MSS to determine initial CWND.
606 * Set 0 to determine the initial CWND by another way */
607 u16 initial_cwnd_multiplier;
609 /** Enable tx pacing for new connections */
612 /** Allow use of TSO whenever available */
615 /** Set if csum offloading is enabled */
618 /** Default congestion control algorithm type */
619 tcp_cc_algorithm_type_e cc_algo;
621 /** Min rwnd, as number of snd_mss segments, for update ack to be sent after
622 * a zero rwnd advertisement */
623 u32 rwnd_min_update_ack;
625 /** Delayed ack time (disabled) */
628 /** Timer ticks to wait for close from app */
631 /** Timer ticks to wait in time-wait. Also known as 2MSL */
634 /** Timer ticks to wait in fin-wait1 to send fin and rcv fin-ack */
637 /** Timer ticks to wait in last ack for ack */
640 /** Timer ticks to wait in fin-wait2 for fin */
643 /** Timer ticks to wait in closing for fin ack */
646 /** Time to wait (sec) before cleaning up the connection */
649 /** Number of preallocated connections */
650 u32 preallocated_connections;
652 /** Number of preallocated half-open connections */
653 u32 preallocated_half_open_connections;
655 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
656 ip4_address_t *ip4_src_addrs;
657 ip6_address_t *ip6_src_addrs;
659 /** Fault-injection. Debug only */
660 f64 buffer_fail_fraction;
661 } tcp_configuration_t;
663 typedef struct _tcp_main
665 /** per-worker context */
666 tcp_worker_ctx_t *wrk_ctx;
668 /* Pool of listeners. */
669 tcp_connection_t *listener_pool;
671 f64 tstamp_ticks_per_clock;
673 /** vlib buffer size */
674 u32 bytes_per_buffer;
676 /** Dispatch table by state and flags */
677 tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64];
679 clib_spinlock_t half_open_lock;
681 /** Pool of half-open connections on which we've sent a SYN */
682 tcp_connection_t *half_open_connections;
684 /** Seed used to generate random iss */
685 tcp_iss_seed_t iss_seed;
687 /** Congestion control algorithms registered */
688 tcp_cc_algorithm_t *cc_algos;
690 /** Hash table of cc algorithms by name */
691 uword *cc_algo_by_name;
693 /** Last cc algo registered */
694 tcp_cc_algorithm_type_e cc_last_type;
696 /** Flag that indicates if stack is on or off */
699 /** Flag that indicates if v4 punting is enabled */
702 /** Flag that indicates if v6 punting is enabled */
705 /** Rotor for v4 source addresses */
706 u32 last_v4_addr_rotor;
708 /** Rotor for v6 source addresses */
709 u32 last_v6_addr_rotor;
711 /** Protocol configuration */
712 tcp_configuration_t cfg;
715 extern tcp_main_t tcp_main;
716 extern vlib_node_registration_t tcp4_input_node;
717 extern vlib_node_registration_t tcp6_input_node;
718 extern vlib_node_registration_t tcp4_output_node;
719 extern vlib_node_registration_t tcp6_output_node;
720 extern vlib_node_registration_t tcp4_established_node;
721 extern vlib_node_registration_t tcp6_established_node;
722 extern vlib_node_registration_t tcp4_syn_sent_node;
723 extern vlib_node_registration_t tcp6_syn_sent_node;
724 extern vlib_node_registration_t tcp4_rcv_process_node;
725 extern vlib_node_registration_t tcp6_rcv_process_node;
726 extern vlib_node_registration_t tcp4_listen_node;
727 extern vlib_node_registration_t tcp6_listen_node;
729 #define tcp_cfg tcp_main.cfg
730 #define tcp_node_index(node_id, is_ip4) \
731 ((is_ip4) ? tcp4_##node_id##_node.index : tcp6_##node_id##_node.index)
733 always_inline tcp_main_t *
739 always_inline tcp_worker_ctx_t *
740 tcp_get_worker (u32 thread_index)
742 ASSERT (thread_index < vec_len (tcp_main.wrk_ctx));
743 return &tcp_main.wrk_ctx[thread_index];
746 always_inline tcp_header_t *
747 tcp_buffer_hdr (vlib_buffer_t * b)
749 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
750 return (tcp_header_t *) (b->data + b->current_data
751 + vnet_buffer (b)->tcp.hdr_offset);
754 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
755 #define tcp_trajectory_add_start(b, start) \
757 (*vlib_buffer_trace_trajectory_cb) (b, start); \
760 #define tcp_trajectory_add_start(b, start)
763 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
765 void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
767 always_inline tcp_connection_t *
768 tcp_connection_get (u32 conn_index, u32 thread_index)
770 tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
771 if (PREDICT_FALSE (pool_is_free_index (wrk->connections, conn_index)))
773 return pool_elt_at_index (wrk->connections, conn_index);
776 always_inline tcp_connection_t *
777 tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
779 tcp_worker_ctx_t *wrk;
780 if (thread_index >= vec_len (tcp_main.wrk_ctx))
782 wrk = tcp_get_worker (thread_index);
783 if (pool_is_free_index (wrk->connections, conn_index))
785 return pool_elt_at_index (wrk->connections, conn_index);
788 always_inline tcp_connection_t *
789 tcp_get_connection_from_transport (transport_connection_t * tconn)
791 return (tcp_connection_t *) tconn;
795 tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
798 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
801 void tcp_connection_close (tcp_connection_t * tc);
802 void tcp_connection_cleanup (tcp_connection_t * tc);
803 void tcp_connection_del (tcp_connection_t * tc);
804 int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
805 tcp_connection_t *tcp_connection_alloc (u8 thread_index);
806 tcp_connection_t *tcp_connection_alloc_w_base (u8 thread_index,
807 tcp_connection_t * base);
808 void tcp_connection_free (tcp_connection_t * tc);
809 int tcp_configure_v4_source_address_range (vlib_main_t * vm,
810 ip4_address_t * start,
811 ip4_address_t * end, u32 table_id);
812 int tcp_configure_v6_source_address_range (vlib_main_t * vm,
813 ip6_address_t * start,
814 ip6_address_t * end, u32 table_id);
815 void tcp_api_reference (void);
816 u8 *format_tcp_connection (u8 * s, va_list * args);
817 u8 *format_tcp_connection_id (u8 * s, va_list * args);
819 always_inline tcp_connection_t *
820 tcp_listener_get (u32 tli)
822 tcp_connection_t *tc = 0;
823 if (!pool_is_free_index (tcp_main.listener_pool, tli))
824 tc = pool_elt_at_index (tcp_main.listener_pool, tli);
828 always_inline tcp_connection_t *
829 tcp_half_open_connection_get (u32 conn_index)
831 tcp_connection_t *tc = 0;
832 clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
833 if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
834 tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
835 clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
839 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
840 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
841 void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
842 u32 thread_index, u8 is_ip4);
843 void tcp_send_reset (tcp_connection_t * tc);
844 void tcp_send_syn (tcp_connection_t * tc);
845 void tcp_send_synack (tcp_connection_t * tc);
846 void tcp_send_fin (tcp_connection_t * tc);
847 void tcp_send_ack (tcp_connection_t * tc);
848 void tcp_update_burst_snd_vars (tcp_connection_t * tc);
849 void tcp_update_rto (tcp_connection_t * tc);
850 void tcp_send_window_update_ack (tcp_connection_t * tc);
852 void tcp_program_ack (tcp_connection_t * tc);
853 void tcp_program_dupack (tcp_connection_t * tc);
854 void tcp_program_retransmit (tcp_connection_t * tc);
861 * Byte tracker initialize
863 * @param tc connection for which the byte tracker should be allocated and
866 void tcp_bt_init (tcp_connection_t * tc);
868 * Byte tracker cleanup
870 * @param tc connection for which the byte tracker should be cleaned up
872 void tcp_bt_cleanup (tcp_connection_t * tc);
874 * Flush byte tracker samples
876 * @param tc tcp connection for which samples should be flushed
878 void tcp_bt_flush_samples (tcp_connection_t * tc);
880 * Track a tcp tx burst
882 * @param tc tcp connection
884 void tcp_bt_track_tx (tcp_connection_t * tc, u32 len);
886 * Track a tcp retransmission
888 * @param tc tcp connection
889 * @param start start sequence number
890 * @param end end sequence number
892 void tcp_bt_track_rxt (tcp_connection_t * tc, u32 start, u32 end);
894 * Generate a delivery rate sample from recently acked bytes
896 * @param tc tcp connection
897 * @param rs resulting rate sample
899 void tcp_bt_sample_delivery_rate (tcp_connection_t * tc,
900 tcp_rate_sample_t * rs);
902 * Check if sample to be generated is app limited
904 * @param tc tcp connection
906 void tcp_bt_check_app_limited (tcp_connection_t * tc);
908 * Check if the byte tracker is in sane state
910 * Should be used only for testing
912 * @param bt byte tracker
914 int tcp_bt_is_sane (tcp_byte_tracker_t * bt);
915 u8 *format_tcp_bt (u8 * s, va_list * args);
918 tcp_end_seq (tcp_header_t * th, u32 len)
920 return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len;
923 /* Modulo arithmetic for TCP sequence numbers */
924 #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0)
925 #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0)
926 #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0)
927 #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0)
928 #define seq_max(_s1, _s2) (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
930 /* Modulo arithmetic for timestamps */
931 #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
932 #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
935 * Our estimate of the number of bytes that have left the network
938 tcp_bytes_out (const tcp_connection_t * tc)
940 if (tcp_opts_sack_permitted (&tc->rcv_opts))
941 return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
943 return clib_min (tc->rcv_dupacks * tc->snd_mss,
944 tc->snd_nxt - tc->snd_una);
948 * Our estimate of the number of bytes in flight (pipe size)
951 tcp_flight_size (const tcp_connection_t * tc)
955 flight_size = (int) (tc->snd_nxt - tc->snd_una) - tcp_bytes_out (tc)
956 + tc->snd_rxt_bytes - tc->rxt_delivered;
958 ASSERT (flight_size >= 0);
964 * Initial cwnd as per RFC5681
967 tcp_initial_cwnd (const tcp_connection_t * tc)
969 if (tcp_cfg.initial_cwnd_multiplier > 0)
970 return tcp_cfg.initial_cwnd_multiplier * tc->snd_mss;
972 if (tc->snd_mss > 2190)
973 return 2 * tc->snd_mss;
974 else if (tc->snd_mss > 1095)
975 return 3 * tc->snd_mss;
977 return 4 * tc->snd_mss;
981 * Accumulate acked bytes for cwnd increase
983 * Once threshold bytes are accumulated, snd_mss bytes are added
987 tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
989 tc->cwnd_acc_bytes += bytes;
990 if (tc->cwnd_acc_bytes >= thresh)
992 u32 inc = tc->cwnd_acc_bytes / thresh;
993 tc->cwnd_acc_bytes -= inc * thresh;
994 tc->cwnd += inc * tc->snd_mss;
995 tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
1000 tcp_loss_wnd (const tcp_connection_t * tc)
1002 /* Whatever we have in flight + the packet we're about to send */
1003 return tcp_flight_size (tc) + tc->snd_mss;
1007 tcp_available_snd_wnd (const tcp_connection_t * tc)
1009 return clib_min (tc->cwnd, tc->snd_wnd);
1013 tcp_available_output_snd_space (const tcp_connection_t * tc)
1015 u32 available_wnd = tcp_available_snd_wnd (tc);
1016 int flight_size = (int) (tc->snd_nxt - tc->snd_una);
1018 if (available_wnd <= flight_size)
1021 return available_wnd - flight_size;
1025 * Estimate of how many bytes we can still push into the network
1028 tcp_available_cc_snd_space (const tcp_connection_t * tc)
1030 u32 available_wnd = tcp_available_snd_wnd (tc);
1031 u32 flight_size = tcp_flight_size (tc);
1033 if (available_wnd <= flight_size)
1036 return available_wnd - flight_size;
1040 tcp_is_lost_fin (tcp_connection_t * tc)
1042 if ((tc->flags & TCP_CONN_FINSNT) && (tc->snd_una_max - tc->snd_una == 1))
1047 u32 tcp_snd_space (tcp_connection_t * tc);
1048 int tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc);
1050 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
1052 /* Made public for unit testing only */
1053 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
1054 u32 tcp_sack_list_bytes (tcp_connection_t * tc);
1059 return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
1063 tcp_time_now_w_thread (u32 thread_index)
1065 return tcp_main.wrk_ctx[thread_index].time_now;
1069 * Generate timestamp for tcp connection
1072 tcp_tstamp (tcp_connection_t * tc)
1074 return (tcp_main.wrk_ctx[tc->c_thread_index].time_now -
1075 tc->timestamp_delta);
1079 tcp_time_now_us (u32 thread_index)
1081 return transport_time_now (thread_index);
1085 tcp_set_time_now (tcp_worker_ctx_t * wrk)
1087 wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
1088 return wrk->time_now;
1091 u32 tcp_session_push_header (transport_connection_t * tconn,
1093 int tcp_session_custom_tx (void *conn, u32 max_burst_size);
1095 void tcp_connection_timers_init (tcp_connection_t * tc);
1096 void tcp_connection_timers_reset (tcp_connection_t * tc);
1097 void tcp_init_snd_vars (tcp_connection_t * tc);
1098 void tcp_connection_init_vars (tcp_connection_t * tc);
1099 void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
1100 void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
1102 void tcp_program_cleanup (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
1105 tcp_cc_rcv_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1107 tc->cc_algo->rcv_ack (tc, rs);
1108 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1112 tcp_cc_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1113 tcp_rate_sample_t * rs)
1115 tc->cc_algo->rcv_cong_ack (tc, ack_type, rs);
1119 tcp_cc_congestion (tcp_connection_t * tc)
1121 tc->cc_algo->congestion (tc);
1125 tcp_cc_loss (tcp_connection_t * tc)
1127 tc->cc_algo->loss (tc);
1131 tcp_cc_recovered (tcp_connection_t * tc)
1133 tc->cc_algo->recovered (tc);
1137 tcp_cc_undo_recovery (tcp_connection_t * tc)
1139 if (tc->cc_algo->undo_recovery)
1140 tc->cc_algo->undo_recovery (tc);
1144 tcp_cc_event (tcp_connection_t * tc, tcp_cc_event_t evt)
1146 if (tc->cc_algo->event)
1147 tc->cc_algo->event (tc, evt);
1151 tcp_cc_get_pacing_rate (tcp_connection_t * tc)
1153 if (tc->cc_algo->get_pacing_rate)
1154 return tc->cc_algo->get_pacing_rate (tc);
1156 f64 srtt = clib_min ((f64) tc->srtt * TCP_TICK, tc->mrtt_us);
1158 /* TODO should constrain to interface's max throughput but
1159 * we don't have link speeds for sw ifs ..*/
1160 return ((f64) tc->cwnd / srtt);
1164 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
1166 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1167 ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
1168 tc->timers[timer_id] =
1169 tw_timer_start_16t_2w_512sl (&tcp_main.
1170 wrk_ctx[tc->c_thread_index].timer_wheel,
1171 tc->c_c_index, timer_id, interval);
1175 tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
1177 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1178 if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
1181 tw_timer_stop_16t_2w_512sl (&tcp_main.
1182 wrk_ctx[tc->c_thread_index].timer_wheel,
1183 tc->timers[timer_id]);
1184 tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
1188 tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
1190 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1191 if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
1192 tw_timer_update_16t_2w_512sl (&tcp_main.
1193 wrk_ctx[tc->c_thread_index].timer_wheel,
1194 tc->timers[timer_id], interval);
1196 tc->timers[timer_id] =
1197 tw_timer_start_16t_2w_512sl (&tcp_main.
1198 wrk_ctx[tc->c_thread_index].timer_wheel,
1199 tc->c_c_index, timer_id, interval);
1203 tcp_retransmit_timer_set (tcp_connection_t * tc)
1205 ASSERT (tc->snd_una != tc->snd_una_max);
1206 tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
1207 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1211 tcp_retransmit_timer_reset (tcp_connection_t * tc)
1213 tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
1217 tcp_retransmit_timer_force_update (tcp_connection_t * tc)
1219 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1220 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1224 tcp_persist_timer_set (tcp_connection_t * tc)
1226 /* Reuse RTO. It's backed off in handler */
1227 tcp_timer_set (tc, TCP_TIMER_PERSIST,
1228 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1232 tcp_persist_timer_update (tcp_connection_t * tc)
1236 if (seq_leq (tc->snd_una, tc->snd_congestion + tc->burst_acked))
1239 interval = clib_max (tc->rto * TCP_TO_TIMER_TICK, 1);
1241 tcp_timer_update (tc, TCP_TIMER_PERSIST, interval);
1245 tcp_persist_timer_reset (tcp_connection_t * tc)
1247 tcp_timer_reset (tc, TCP_TIMER_PERSIST);
1251 tcp_retransmit_timer_update (tcp_connection_t * tc)
1253 if (tc->snd_una == tc->snd_nxt)
1255 tcp_retransmit_timer_reset (tc);
1256 if (tc->snd_wnd < tc->snd_mss)
1257 tcp_persist_timer_update (tc);
1260 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1261 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1265 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
1267 return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
1270 #define tcp_validate_txf_size(_tc, _a) \
1271 ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
1272 || transport_max_tx_dequeue (&_tc->connection) >= _a)
1274 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
1275 u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
1278 * Register exiting cc algo type
1280 void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
1281 const tcp_cc_algorithm_t * vft);
1284 * Register new cc algo type
1286 tcp_cc_algorithm_type_e tcp_cc_algo_new_type (const tcp_cc_algorithm_t * vft);
1287 tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
1289 static inline void *
1290 tcp_cc_data (tcp_connection_t * tc)
1292 return (void *) tc->cc_data;
1295 void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1296 tcp_rate_sample_t * rs);
1299 * Push TCP header to buffer
1301 * @param vm - vlib_main
1302 * @param b - buffer to write the header to
1303 * @param sp_net - source port net order
1304 * @param dp_net - destination port net order
1305 * @param seq - sequence number net order
1306 * @param ack - ack number net order
1307 * @param tcp_hdr_opts_len - header and options length in bytes
1308 * @param flags - header flags
1309 * @param wnd - window size
1311 * @return - pointer to start of TCP header
1313 always_inline void *
1314 vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq,
1315 u32 ack, u8 tcp_hdr_opts_len, u8 flags,
1320 th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len);
1324 th->seq_number = seq;
1325 th->ack_number = ack;
1326 th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4;
1330 th->urgent_pointer = 0;
1331 vnet_buffer (b)->l4_hdr_offset = (u8 *) th - b->data;
1332 b->flags |= VNET_BUFFER_F_L4_HDR_OFFSET_VALID;
1337 * Push TCP header to buffer
1339 * @param b - buffer to write the header to
1340 * @param sp_net - source port net order
1341 * @param dp_net - destination port net order
1342 * @param seq - sequence number host order
1343 * @param ack - ack number host order
1344 * @param tcp_hdr_opts_len - header and options length in bytes
1345 * @param flags - header flags
1346 * @param wnd - window size
1348 * @return - pointer to start of TCP header
1350 always_inline void *
1351 vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq,
1352 u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
1354 return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net,
1355 clib_host_to_net_u32 (seq),
1356 clib_host_to_net_u32 (ack),
1357 tcp_hdr_opts_len, flags,
1358 clib_host_to_net_u16 (wnd));
1361 #endif /* _vnet_tcp_h_ */
1364 * fd.io coding-style-patch-verification: ON
1367 * eval: (c-set-style "gnu")