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
35 #define TCP_DUPACK_THRESHOLD 3
36 #define TCP_MAX_RX_FIFO_SIZE 32 << 20
37 #define TCP_MIN_RX_FIFO_SIZE 4 << 10
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") \
75 _(WAITCLOSE, "WAIT CLOSE") \
76 _(RETRANSMIT_SYN, "RETRANSMIT SYN") \
77 _(ESTABLISH, "ESTABLISH") \
78 _(ESTABLISH_AO, "ESTABLISH_AO") \
80 typedef enum _tcp_timers
82 #define _(sym, str) TCP_TIMER_##sym,
88 typedef void (timer_expiration_handler) (u32 index);
90 extern timer_expiration_handler tcp_timer_delack_handler;
91 extern timer_expiration_handler tcp_timer_retransmit_handler;
92 extern timer_expiration_handler tcp_timer_persist_handler;
93 extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
95 #define TCP_TIMER_HANDLE_INVALID ((u32) ~0)
97 /* Timer delays as multiples of 100ms */
98 #define TCP_TO_TIMER_TICK TCP_TICK*10 /* Period for converting from TCP
99 * ticks to timer units */
100 #define TCP_DELACK_TIME 1 /* 0.1s */
101 #define TCP_ESTABLISH_TIME 750 /* 75s */
102 #define TCP_SYN_RCVD_TIME 600 /* 60s */
103 #define TCP_2MSL_TIME 300 /* 30s */
104 #define TCP_CLOSEWAIT_TIME 20 /* 2s */
105 #define TCP_TIMEWAIT_TIME 100 /* 10s */
106 #define TCP_FINWAIT1_TIME 600 /* 60s */
107 #define TCP_CLEANUP_TIME 1 /* 0.1s */
108 #define TCP_TIMER_PERSIST_MIN 2 /* 0.2s */
110 #define TCP_RTO_MAX 60 * THZ /* Min max RTO (60s) as per RFC6298 */
111 #define TCP_RTO_MIN 0.2 * THZ /* Min RTO (200ms) - lower than standard */
112 #define TCP_RTT_MAX 30 * THZ /* 30s (probably too much) */
113 #define TCP_RTO_SYN_RETRIES 3 /* SYN retries without doubling RTO */
114 #define TCP_RTO_INIT 1 * THZ /* Initial retransmit timer */
116 /** TCP connection flags */
117 #define foreach_tcp_connection_flag \
118 _(SNDACK, "Send ACK") \
119 _(FINSNT, "FIN sent") \
120 _(RECOVERY, "Recovery") \
121 _(FAST_RECOVERY, "Fast Recovery") \
122 _(DCNT_PENDING, "Disconnect pending") \
123 _(HALF_OPEN_DONE, "Half-open completed") \
124 _(FINPNDG, "FIN pending") \
125 _(FRXT_PENDING, "Fast-retransmit pending") \
126 _(FRXT_FIRST, "Fast-retransmit first again") \
127 _(DEQ_PENDING, "Pending dequeue acked") \
128 _(PSH_PENDING, "PSH pending") \
129 _(FINRCVD, "FIN received") \
131 typedef enum _tcp_connection_flag_bits
133 #define _(sym, str) TCP_CONN_##sym##_BIT,
134 foreach_tcp_connection_flag
137 } tcp_connection_flag_bits_e;
139 typedef enum _tcp_connection_flag
141 #define _(sym, str) TCP_CONN_##sym = 1 << TCP_CONN_##sym##_BIT,
142 foreach_tcp_connection_flag
145 } tcp_connection_flags_e;
147 #define TCP_SCOREBOARD_TRACE (0)
148 #define TCP_MAX_SACK_BLOCKS 256 /**< Max number of SACK blocks stored */
149 #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0)
151 typedef struct _scoreboard_trace_elt
158 } scoreboard_trace_elt_t;
160 typedef struct _sack_scoreboard_hole
162 u32 next; /**< Index for next entry in linked list */
163 u32 prev; /**< Index for previous entry in linked list */
164 u32 start; /**< Start sequence number */
165 u32 end; /**< End sequence number */
166 u8 is_lost; /**< Mark hole as lost */
167 } sack_scoreboard_hole_t;
169 typedef struct _sack_scoreboard
171 sack_scoreboard_hole_t *holes; /**< Pool of holes */
172 u32 head; /**< Index of first entry */
173 u32 tail; /**< Index of last entry */
174 u32 sacked_bytes; /**< Number of bytes sacked in sb */
175 u32 last_sacked_bytes; /**< Number of bytes last sacked */
176 u32 last_bytes_delivered; /**< Number of sack bytes delivered */
177 u32 snd_una_adv; /**< Bytes to add to snd_una */
178 u32 high_sacked; /**< Highest byte sacked (fack) */
179 u32 high_rxt; /**< Highest retransmitted sequence */
180 u32 rescue_rxt; /**< Rescue sequence number */
181 u32 lost_bytes; /**< Bytes lost as per RFC6675 */
182 u32 cur_rxt_hole; /**< Retransmitting from this hole */
184 #if TCP_SCOREBOARD_TRACE
185 scoreboard_trace_elt_t *trace;
190 #if TCP_SCOREBOARD_TRACE
191 #define tcp_scoreboard_trace_add(_tc, _ack) \
193 static u64 _group = 0; \
194 sack_scoreboard_t *_sb = &_tc->sack_sb; \
195 sack_block_t *_sack, *_sacks; \
196 scoreboard_trace_elt_t *_elt; \
199 _sacks = _tc->rcv_opts.sacks; \
200 for (i = 0; i < vec_len (_sacks); i++) \
202 _sack = &_sacks[i]; \
203 vec_add2 (_sb->trace, _elt, 1); \
204 _elt->start = _sack->start; \
205 _elt->end = _sack->end; \
206 _elt->ack = _elt->end == _ack ? _ack : 0; \
207 _elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0; \
208 _elt->group = _group; \
212 #define tcp_scoreboard_trace_add(_tc, _ack)
215 sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
216 sack_scoreboard_hole_t *
217 start, u8 have_sent_1_smss,
220 sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
223 sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
224 sack_scoreboard_hole_t * hole);
225 sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
226 sack_scoreboard_hole_t * hole);
227 sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
228 sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
229 void scoreboard_clear (sack_scoreboard_t * sb);
230 void scoreboard_init (sack_scoreboard_t * sb);
231 u8 *format_tcp_scoreboard (u8 * s, va_list * args);
233 typedef enum _tcp_cc_algorithm_type
237 } tcp_cc_algorithm_type_e;
239 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
241 typedef enum _tcp_cc_ack_t
248 typedef struct _tcp_connection
250 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
251 transport_connection_t connection; /**< Common transport data. First! */
253 u8 state; /**< TCP state as per tcp_state_t */
254 u16 flags; /**< Connection flags (see tcp_conn_flags_e) */
255 u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */
259 /** Send sequence variables RFC793 */
260 u32 snd_una; /**< oldest unacknowledged sequence number */
261 u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/
262 u32 snd_wnd; /**< send window */
263 u32 snd_wl1; /**< seq number used for last snd.wnd update */
264 u32 snd_wl2; /**< ack number used for last snd.wnd update */
265 u32 snd_nxt; /**< next seq number to be sent */
266 u16 snd_mss; /**< Effective send max seg (data) size */
268 /** Receive sequence variables RFC793 */
269 u32 rcv_nxt; /**< next sequence number expected */
270 u32 rcv_wnd; /**< receive window we expect */
272 u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */
273 u32 iss; /**< initial sent sequence */
274 u32 irs; /**< initial remote sequence */
277 u8 snd_opts_len; /**< Tx options len */
278 u8 rcv_wscale; /**< Window scale to advertise to peer */
279 u8 snd_wscale; /**< Window scale to use when sending */
280 u32 tsval_recent; /**< Last timestamp received */
281 u32 tsval_recent_age; /**< When last updated tstamp_recent*/
282 tcp_options_t snd_opts; /**< Tx options for connection */
283 tcp_options_t rcv_opts; /**< Rx options for connection */
285 sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */
286 u8 snd_sack_pos; /**< Position in vec of first block to send */
287 sack_block_t *snd_sacks_fl; /**< Vector for building new list */
288 sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */
290 u16 rcv_dupacks; /**< Number of DUPACKs received */
291 u8 pending_dupacks; /**< Number of DUPACKs to be sent */
293 /* Congestion control */
294 u32 cwnd; /**< Congestion window */
295 u32 cwnd_acc_bytes; /**< Bytes accumulated for cwnd increment */
296 u32 ssthresh; /**< Slow-start threshold */
297 u32 prev_ssthresh; /**< ssthresh before congestion */
298 u32 prev_cwnd; /**< ssthresh before congestion */
299 u32 bytes_acked; /**< Bytes acknowledged by current segment */
300 u32 burst_acked; /**< Bytes acknowledged in current burst */
301 u32 snd_rxt_bytes; /**< Retransmitted bytes */
302 u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
303 u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
304 u32 snd_congestion; /**< snd_una_max when congestion is detected */
305 tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
306 u8 cc_data[TCP_CC_DATA_SZ]; /**< Congestion control algo private data */
309 u32 rto; /**< Retransmission timeout */
310 u32 rto_boff; /**< Index for RTO backoff */
311 u32 srtt; /**< Smoothed RTT */
312 u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */
313 u32 rtt_seq; /**< Sequence number for tracked ACK */
314 f64 rtt_ts; /**< Timestamp for tracked ACK */
315 f64 mrtt_us; /**< High precision mrtt from tracked acks */
317 u16 mss; /**< Our max seg size that includes options */
318 u32 limited_transmit; /**< snd_nxt when limited transmit starts */
319 u32 last_fib_check; /**< Last time we checked fib route for peer */
320 u32 sw_if_index; /**< Interface for the connection */
321 u32 tx_fifo_size; /**< Tx fifo size. Used to constrain cwnd */
323 u32 psh_seq; /**< Add psh header for seg that includes this */
327 struct _tcp_cc_algorithm
330 uword (*unformat_cfg) (unformat_input_t * input);
331 void (*rcv_ack) (tcp_connection_t * tc);
332 void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack);
333 void (*congestion) (tcp_connection_t * tc);
334 void (*recovered) (tcp_connection_t * tc);
335 void (*init) (tcp_connection_t * tc);
339 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
340 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
341 #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY
342 #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY
343 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
344 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
345 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
346 #define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
347 #define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
348 #define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
349 #define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
350 #define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
351 #define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
353 #define tcp_in_cong_recovery(tc) ((tc)->flags & \
354 (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
357 tcp_cong_recovery_off (tcp_connection_t * tc)
359 tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
360 tcp_fastrecovery_first_off (tc);
363 typedef enum _tcp_error
365 #define tcp_error(n,s) TCP_ERROR_##n,
366 #include <vnet/tcp/tcp_error.def>
371 typedef struct _tcp_lookup_dispatch
374 } tcp_lookup_dispatch_t;
376 typedef struct tcp_worker_ctx_
378 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
382 /** worker timer wheel */
383 tw_timer_wheel_16t_2w_512sl_t timer_wheel;
385 /** tx buffer free list */
388 /** tx frames for tcp 4/6 output nodes */
389 vlib_frame_t *tx_frames[2];
391 /** tx frames for ip 4/6 lookup nodes */
392 vlib_frame_t *ip_lookup_tx_frames[2];
394 /** vector of connections needing fast rxt */
395 u32 *pending_fast_rxt;
397 /** vector of connections now doing fast rxt */
398 u32 *ongoing_fast_rxt;
400 /** vector of connections that will do fast rxt */
401 u32 *postponed_fast_rxt;
403 /** vector of pending ack dequeues */
404 u32 *pending_deq_acked;
406 /** vector of pending acks */
409 /** vector of pending disconnect notifications */
410 u32 *pending_disconnects;
412 /** convenience pointer to this thread's vlib main */
415 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
417 /** cached 'on the wire' options for bursts */
422 typedef struct tcp_iss_seed_
428 typedef struct _tcp_main
430 /* Per-worker thread tcp connection pools */
431 tcp_connection_t **connections;
433 /* Pool of listeners. */
434 tcp_connection_t *listener_pool;
436 /** Dispatch table by state and flags */
437 tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64];
439 u8 log2_tstamp_clocks_per_tick;
440 f64 tstamp_ticks_per_clock;
442 /** per-worker context */
443 tcp_worker_ctx_t *wrk_ctx;
445 /* Pool of half-open connections on which we've sent a SYN */
446 tcp_connection_t *half_open_connections;
447 clib_spinlock_t half_open_lock;
449 /* Congestion control algorithms registered */
450 tcp_cc_algorithm_t *cc_algos;
452 /** vlib buffer size */
453 u32 bytes_per_buffer;
455 /* Seed used to generate random iss */
456 tcp_iss_seed_t iss_seed;
458 /** Hash table of cc algorithms by name */
459 uword *cc_algo_by_name;
465 /* Flag that indicates if stack is on or off */
468 /** Max rx fifo size for a session. It is used in to compute the
469 * rfc 7323 window scaling factor */
472 /** Default MTU to be used when establishing connections */
475 /** Number of preallocated connections */
476 u32 preallocated_connections;
477 u32 preallocated_half_open_connections;
479 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
480 ip4_address_t *ip4_src_addresses;
481 u32 last_v4_address_rotor;
482 u32 last_v6_address_rotor;
483 ip6_address_t *ip6_src_addresses;
485 /** Enable tx pacing for new connections */
491 /** fault-injection */
492 f64 buffer_fail_fraction;
494 /** Default congestion control algorithm type */
495 tcp_cc_algorithm_type_e cc_algo;
499 extern tcp_main_t tcp_main;
500 extern vlib_node_registration_t tcp4_input_node;
501 extern vlib_node_registration_t tcp6_input_node;
502 extern vlib_node_registration_t tcp4_output_node;
503 extern vlib_node_registration_t tcp6_output_node;
504 extern vlib_node_registration_t tcp4_established_node;
505 extern vlib_node_registration_t tcp6_established_node;
506 extern vlib_node_registration_t tcp4_syn_sent_node;
507 extern vlib_node_registration_t tcp6_syn_sent_node;
508 extern vlib_node_registration_t tcp4_rcv_process_node;
509 extern vlib_node_registration_t tcp6_rcv_process_node;
510 extern vlib_node_registration_t tcp4_listen_node;
511 extern vlib_node_registration_t tcp6_listen_node;
513 always_inline tcp_main_t *
519 always_inline tcp_worker_ctx_t *
520 tcp_get_worker (u32 thread_index)
522 return &tcp_main.wrk_ctx[thread_index];
525 always_inline tcp_header_t *
526 tcp_buffer_hdr (vlib_buffer_t * b)
528 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
529 return (tcp_header_t *) (b->data + b->current_data
530 + vnet_buffer (b)->tcp.hdr_offset);
533 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
534 #define tcp_trajectory_add_start(b, start) \
536 (*vlib_buffer_trace_trajectory_cb) (b, start); \
539 #define tcp_trajectory_add_start(b, start)
542 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
544 void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
546 always_inline tcp_connection_t *
547 tcp_connection_get (u32 conn_index, u32 thread_index)
550 (pool_is_free_index (tcp_main.connections[thread_index], conn_index)))
552 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
555 always_inline tcp_connection_t *
556 tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
558 if (tcp_main.connections[thread_index] == 0)
560 if (pool_is_free_index (tcp_main.connections[thread_index], conn_index))
562 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
565 always_inline tcp_connection_t *
566 tcp_get_connection_from_transport (transport_connection_t * tconn)
568 return (tcp_connection_t *) tconn;
572 tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
575 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
578 void tcp_connection_close (tcp_connection_t * tc);
579 void tcp_connection_cleanup (tcp_connection_t * tc);
580 void tcp_connection_del (tcp_connection_t * tc);
581 int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
582 tcp_connection_t *tcp_connection_alloc (u8 thread_index);
583 void tcp_connection_free (tcp_connection_t * tc);
584 void tcp_connection_reset (tcp_connection_t * tc);
585 int tcp_configure_v4_source_address_range (vlib_main_t * vm,
586 ip4_address_t * start,
587 ip4_address_t * end, u32 table_id);
588 int tcp_configure_v6_source_address_range (vlib_main_t * vm,
589 ip6_address_t * start,
590 ip6_address_t * end, u32 table_id);
591 void tcp_api_reference (void);
592 u8 *format_tcp_connection (u8 * s, va_list * args);
594 always_inline tcp_connection_t *
595 tcp_listener_get (u32 tli)
597 return pool_elt_at_index (tcp_main.listener_pool, tli);
600 always_inline tcp_connection_t *
601 tcp_half_open_connection_get (u32 conn_index)
603 tcp_connection_t *tc = 0;
604 clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
605 if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
606 tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
607 clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
611 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
612 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
613 void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
614 u32 thread_index, u8 is_ip4);
615 void tcp_send_reset (tcp_connection_t * tc);
616 void tcp_send_syn (tcp_connection_t * tc);
617 void tcp_send_synack (tcp_connection_t * tc);
618 void tcp_send_fin (tcp_connection_t * tc);
619 void tcp_init_mss (tcp_connection_t * tc);
620 void tcp_update_burst_snd_vars (tcp_connection_t * tc);
621 void tcp_update_rto (tcp_connection_t * tc);
622 void tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4);
623 void tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk);
624 void tcp_program_fastretransmit (tcp_worker_ctx_t * wrk,
625 tcp_connection_t * tc);
626 void tcp_do_fastretransmits (tcp_worker_ctx_t * wrk);
628 void tcp_program_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
629 void tcp_program_dupack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
630 void tcp_send_acks (tcp_worker_ctx_t * wrk);
633 tcp_end_seq (tcp_header_t * th, u32 len)
635 return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len;
638 /* Modulo arithmetic for TCP sequence numbers */
639 #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0)
640 #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0)
641 #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0)
642 #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0)
643 #define seq_max(_s1, _s2) (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
645 /* Modulo arithmetic for timestamps */
646 #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
647 #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
650 * Our estimate of the number of bytes that have left the network
653 tcp_bytes_out (const tcp_connection_t * tc)
655 if (tcp_opts_sack_permitted (&tc->rcv_opts))
656 return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
658 return tc->rcv_dupacks * tc->snd_mss;
662 * Our estimate of the number of bytes in flight (pipe size)
665 tcp_flight_size (const tcp_connection_t * tc)
669 flight_size = (int) (tc->snd_nxt - tc->snd_una) - tcp_bytes_out (tc)
676 ("Negative: %u %u %u dupacks %u sacked bytes %u flags %d",
677 tc->snd_una_max - tc->snd_una, tcp_bytes_out (tc),
678 tc->snd_rxt_bytes, tc->rcv_dupacks, tc->sack_sb.sacked_bytes,
687 * Initial cwnd as per RFC5681
690 tcp_initial_cwnd (const tcp_connection_t * tc)
692 if (tc->snd_mss > 2190)
693 return 2 * tc->snd_mss;
694 else if (tc->snd_mss > 1095)
695 return 3 * tc->snd_mss;
697 return 4 * tc->snd_mss;
701 * Accumulate acked bytes for cwnd increase
703 * Once threshold bytes are accumulated, snd_mss bytes are added
707 tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
709 tc->cwnd_acc_bytes += bytes;
710 if (tc->cwnd_acc_bytes >= thresh)
712 u32 inc = tc->cwnd_acc_bytes / thresh;
713 tc->cwnd_acc_bytes -= inc * thresh;
714 tc->cwnd += inc * tc->snd_mss;
715 tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
720 tcp_loss_wnd (const tcp_connection_t * tc)
726 tcp_available_snd_wnd (const tcp_connection_t * tc)
728 return clib_min (tc->cwnd, tc->snd_wnd);
732 tcp_available_output_snd_space (const tcp_connection_t * tc)
734 u32 available_wnd = tcp_available_snd_wnd (tc);
735 int flight_size = (int) (tc->snd_nxt - tc->snd_una);
737 if (available_wnd <= flight_size)
740 return available_wnd - flight_size;
744 * Estimate of how many bytes we can still push into the network
747 tcp_available_cc_snd_space (const tcp_connection_t * tc)
749 u32 available_wnd = tcp_available_snd_wnd (tc);
750 u32 flight_size = tcp_flight_size (tc);
752 if (available_wnd <= flight_size)
755 return available_wnd - flight_size;
759 tcp_is_lost_fin (tcp_connection_t * tc)
761 if ((tc->flags & TCP_CONN_FINSNT) && tc->snd_una_max - tc->snd_una == 1)
766 u32 tcp_snd_space (tcp_connection_t * tc);
767 int tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk,
768 tcp_connection_t * tc);
769 int tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk,
770 tcp_connection_t * tc, u32 burst_size);
771 int tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
773 int tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
775 void tcp_cc_init_congestion (tcp_connection_t * tc);
776 void tcp_cc_fastrecovery_exit (tcp_connection_t * tc);
778 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
780 /* Made public for unit testing only */
781 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
782 u32 tcp_sack_list_bytes (tcp_connection_t * tc);
787 return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
791 tcp_time_now_w_thread (u32 thread_index)
793 return tcp_main.wrk_ctx[thread_index].time_now;
797 tcp_time_now_us (u32 thread_index)
799 return transport_time_now (thread_index);
803 tcp_set_time_now (tcp_worker_ctx_t * wrk)
805 wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
806 return wrk->time_now;
809 u32 tcp_session_push_header (transport_connection_t * tconn,
812 void tcp_connection_timers_init (tcp_connection_t * tc);
813 void tcp_connection_timers_reset (tcp_connection_t * tc);
814 void tcp_init_snd_vars (tcp_connection_t * tc);
815 void tcp_connection_init_vars (tcp_connection_t * tc);
816 void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
817 void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
821 tcp_cc_rcv_ack (tcp_connection_t * tc)
823 tc->cc_algo->rcv_ack (tc);
824 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
828 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
830 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
831 ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
832 tc->timers[timer_id] =
833 tw_timer_start_16t_2w_512sl (&tcp_main.
834 wrk_ctx[tc->c_thread_index].timer_wheel,
835 tc->c_c_index, timer_id, interval);
839 tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
841 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
842 if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
845 tw_timer_stop_16t_2w_512sl (&tcp_main.
846 wrk_ctx[tc->c_thread_index].timer_wheel,
847 tc->timers[timer_id]);
848 tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
852 tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
854 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
855 if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
856 tw_timer_update_16t_2w_512sl (&tcp_main.
857 wrk_ctx[tc->c_thread_index].timer_wheel,
858 tc->timers[timer_id], interval);
860 tc->timers[timer_id] =
861 tw_timer_start_16t_2w_512sl (&tcp_main.
862 wrk_ctx[tc->c_thread_index].timer_wheel,
863 tc->c_c_index, timer_id, interval);
867 tcp_retransmit_timer_set (tcp_connection_t * tc)
869 ASSERT (tc->snd_una != tc->snd_una_max);
870 tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
871 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
875 tcp_retransmit_timer_reset (tcp_connection_t * tc)
877 tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
881 tcp_retransmit_timer_force_update (tcp_connection_t * tc)
883 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
884 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
888 tcp_persist_timer_set (tcp_connection_t * tc)
890 /* Reuse RTO. It's backed off in handler */
891 tcp_timer_set (tc, TCP_TIMER_PERSIST,
892 clib_max (tc->rto * TCP_TO_TIMER_TICK,
893 TCP_TIMER_PERSIST_MIN));
897 tcp_persist_timer_update (tcp_connection_t * tc)
899 tcp_timer_update (tc, TCP_TIMER_PERSIST,
900 clib_max (tc->rto * TCP_TO_TIMER_TICK,
901 TCP_TIMER_PERSIST_MIN));
905 tcp_persist_timer_reset (tcp_connection_t * tc)
907 tcp_timer_reset (tc, TCP_TIMER_PERSIST);
911 tcp_retransmit_timer_update (tcp_connection_t * tc)
913 if (tc->snd_una == tc->snd_nxt)
915 tcp_retransmit_timer_reset (tc);
916 if (tc->snd_wnd < tc->snd_mss)
917 tcp_persist_timer_update (tc);
920 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
921 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
925 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
927 return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
930 #define tcp_validate_txf_size(_tc, _a) \
931 ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
932 || transport_max_tx_dequeue (&_tc->connection) >= _a)
934 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
935 u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
937 void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
938 const tcp_cc_algorithm_t * vft);
940 tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
943 tcp_cc_data (tcp_connection_t * tc)
945 return (void *) tc->cc_data;
948 void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type);
951 * Push TCP header to buffer
953 * @param vm - vlib_main
954 * @param b - buffer to write the header to
955 * @param sp_net - source port net order
956 * @param dp_net - destination port net order
957 * @param seq - sequence number net order
958 * @param ack - ack number net order
959 * @param tcp_hdr_opts_len - header and options length in bytes
960 * @param flags - header flags
961 * @param wnd - window size
963 * @return - pointer to start of TCP header
966 vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq,
967 u32 ack, u8 tcp_hdr_opts_len, u8 flags,
972 th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len);
976 th->seq_number = seq;
977 th->ack_number = ack;
978 th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4;
982 th->urgent_pointer = 0;
987 * Push TCP header to buffer
989 * @param b - buffer to write the header to
990 * @param sp_net - source port net order
991 * @param dp_net - destination port net order
992 * @param seq - sequence number host order
993 * @param ack - ack number host order
994 * @param tcp_hdr_opts_len - header and options length in bytes
995 * @param flags - header flags
996 * @param wnd - window size
998 * @return - pointer to start of TCP header
1000 always_inline void *
1001 vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq,
1002 u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
1004 return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net,
1005 clib_host_to_net_u32 (seq),
1006 clib_host_to_net_u32 (ack),
1007 tcp_hdr_opts_len, flags,
1008 clib_host_to_net_u16 (wnd));
1011 #endif /* _vnet_tcp_h_ */
1014 * fd.io coding-style-patch-verification: ON
1017 * eval: (c-set-style "gnu")