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 */
115 #define TCP_RTO_BOFF_MAX 8 /* Max number of retries before reset */
117 /** TCP connection flags */
118 #define foreach_tcp_connection_flag \
119 _(SNDACK, "Send ACK") \
120 _(FINSNT, "FIN sent") \
121 _(RECOVERY, "Recovery") \
122 _(FAST_RECOVERY, "Fast Recovery") \
123 _(DCNT_PENDING, "Disconnect pending") \
124 _(HALF_OPEN_DONE, "Half-open completed") \
125 _(FINPNDG, "FIN pending") \
126 _(FRXT_PENDING, "Fast-retransmit pending") \
127 _(FRXT_FIRST, "Fast-retransmit first again") \
128 _(DEQ_PENDING, "Pending dequeue acked") \
129 _(PSH_PENDING, "PSH pending") \
130 _(FINRCVD, "FIN received") \
131 _(RATE_SAMPLE, "Conn does rate sampling") \
132 _(TRACK_BURST, "Track burst") \
133 _(ZERO_RWND_SENT, "Zero RWND sent") \
135 typedef enum _tcp_connection_flag_bits
137 #define _(sym, str) TCP_CONN_##sym##_BIT,
138 foreach_tcp_connection_flag
141 } tcp_connection_flag_bits_e;
143 typedef enum _tcp_connection_flag
145 #define _(sym, str) TCP_CONN_##sym = 1 << TCP_CONN_##sym##_BIT,
146 foreach_tcp_connection_flag
149 } tcp_connection_flags_e;
151 #define TCP_SCOREBOARD_TRACE (0)
152 #define TCP_MAX_SACK_BLOCKS 256 /**< Max number of SACK blocks stored */
153 #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0)
155 typedef struct _scoreboard_trace_elt
162 } scoreboard_trace_elt_t;
164 typedef struct _sack_scoreboard_hole
166 u32 next; /**< Index for next entry in linked list */
167 u32 prev; /**< Index for previous entry in linked list */
168 u32 start; /**< Start sequence number */
169 u32 end; /**< End sequence number */
170 u8 is_lost; /**< Mark hole as lost */
171 } sack_scoreboard_hole_t;
173 typedef struct _sack_scoreboard
175 sack_scoreboard_hole_t *holes; /**< Pool of holes */
176 u32 head; /**< Index of first entry */
177 u32 tail; /**< Index of last entry */
178 u32 sacked_bytes; /**< Number of bytes sacked in sb */
179 u32 last_sacked_bytes; /**< Number of bytes last sacked */
180 u32 last_bytes_delivered; /**< Sack bytes delivered to app */
181 u32 snd_una_adv; /**< Bytes to add to snd_una */
182 u32 high_sacked; /**< Highest byte sacked (fack) */
183 u32 high_rxt; /**< Highest retransmitted sequence */
184 u32 rescue_rxt; /**< Rescue sequence number */
185 u32 lost_bytes; /**< Bytes lost as per RFC6675 */
186 u32 cur_rxt_hole; /**< Retransmitting from this hole */
188 #if TCP_SCOREBOARD_TRACE
189 scoreboard_trace_elt_t *trace;
194 #if TCP_SCOREBOARD_TRACE
195 #define tcp_scoreboard_trace_add(_tc, _ack) \
197 static u64 _group = 0; \
198 sack_scoreboard_t *_sb = &_tc->sack_sb; \
199 sack_block_t *_sack, *_sacks; \
200 scoreboard_trace_elt_t *_elt; \
203 _sacks = _tc->rcv_opts.sacks; \
204 for (i = 0; i < vec_len (_sacks); i++) \
206 _sack = &_sacks[i]; \
207 vec_add2 (_sb->trace, _elt, 1); \
208 _elt->start = _sack->start; \
209 _elt->end = _sack->end; \
210 _elt->ack = _elt->end == _ack ? _ack : 0; \
211 _elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0; \
212 _elt->group = _group; \
216 #define tcp_scoreboard_trace_add(_tc, _ack)
219 sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
220 sack_scoreboard_hole_t *
221 start, u8 have_sent_1_smss,
224 sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
227 sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
228 sack_scoreboard_hole_t * hole);
229 sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
230 sack_scoreboard_hole_t * hole);
231 sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
232 sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
233 void scoreboard_clear (sack_scoreboard_t * sb);
234 void scoreboard_init (sack_scoreboard_t * sb);
235 u8 *format_tcp_scoreboard (u8 * s, va_list * args);
237 #define TCP_BTS_INVALID_INDEX ((u32)~0)
239 typedef enum tcp_bts_flags_
242 TCP_BTS_IS_APP_LIMITED = 1 << 1,
243 } __clib_packed tcp_bts_flags_t;
245 typedef struct tcp_bt_sample_
247 u32 next; /**< Next sample index in list */
248 u32 prev; /**< Previous sample index in list */
249 u32 min_seq; /**< Min seq number in sample */
250 u32 max_seq; /**< Max seq number. Set for rxt samples */
251 u64 delivered; /**< Total delivered when sample taken */
252 f64 delivered_time; /**< Delivered time when sample taken */
253 u64 tx_rate; /**< Tx pacing rate */
254 tcp_bts_flags_t flags; /**< Sample flag */
257 typedef struct tcp_rate_sample_
259 u64 sample_delivered; /**< Delivered of sample used for rate */
260 u32 delivered; /**< Bytes delivered in ack time */
261 f64 ack_time; /**< Time to ack the bytes delivered */
262 u64 tx_rate; /**< Tx pacing rate */
263 tcp_bts_flags_t flags; /**< Rate sample flags from bt sample */
266 typedef struct tcp_byte_tracker_
268 tcp_bt_sample_t *samples; /**< Pool of samples */
269 rb_tree_t sample_lookup; /**< Rbtree for sample lookup by min_seq */
270 u32 head; /**< Head of samples linked list */
271 u32 tail; /**< Tail of samples linked list */
272 u32 last_ooo; /**< Cached last ooo sample */
273 } tcp_byte_tracker_t;
275 typedef enum _tcp_cc_algorithm_type
279 TCP_CC_LAST = TCP_CC_CUBIC
280 } tcp_cc_algorithm_type_e;
282 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
284 typedef enum _tcp_cc_ack_t
291 typedef struct _tcp_connection
293 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
294 transport_connection_t connection; /**< Common transport data. First! */
296 u8 state; /**< TCP state as per tcp_state_t */
297 u16 flags; /**< Connection flags (see tcp_conn_flags_e) */
298 u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */
302 /** Send sequence variables RFC793 */
303 u32 snd_una; /**< oldest unacknowledged sequence number */
304 u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/
305 u32 snd_wnd; /**< send window */
306 u32 snd_wl1; /**< seq number used for last snd.wnd update */
307 u32 snd_wl2; /**< ack number used for last snd.wnd update */
308 u32 snd_nxt; /**< next seq number to be sent */
309 u16 snd_mss; /**< Effective send max seg (data) size */
311 /** Receive sequence variables RFC793 */
312 u32 rcv_nxt; /**< next sequence number expected */
313 u32 rcv_wnd; /**< receive window we expect */
315 u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */
316 u32 iss; /**< initial sent sequence */
317 u32 irs; /**< initial remote sequence */
320 u8 snd_opts_len; /**< Tx options len */
321 u8 rcv_wscale; /**< Window scale to advertise to peer */
322 u8 snd_wscale; /**< Window scale to use when sending */
323 u32 tsval_recent; /**< Last timestamp received */
324 u32 tsval_recent_age; /**< When last updated tstamp_recent*/
325 tcp_options_t snd_opts; /**< Tx options for connection */
326 tcp_options_t rcv_opts; /**< Rx options for connection */
328 sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */
329 u8 snd_sack_pos; /**< Position in vec of first block to send */
330 sack_block_t *snd_sacks_fl; /**< Vector for building new list */
331 sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */
333 u16 rcv_dupacks; /**< Number of DUPACKs received */
334 u8 pending_dupacks; /**< Number of DUPACKs to be sent */
336 /* Congestion control */
337 u32 cwnd; /**< Congestion window */
338 u32 cwnd_acc_bytes; /**< Bytes accumulated for cwnd increment */
339 u32 ssthresh; /**< Slow-start threshold */
340 u32 prev_ssthresh; /**< ssthresh before congestion */
341 u32 prev_cwnd; /**< ssthresh before congestion */
342 u32 bytes_acked; /**< Bytes acknowledged by current segment */
343 u32 burst_acked; /**< Bytes acknowledged in current burst */
344 u32 snd_rxt_bytes; /**< Retransmitted bytes */
345 u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
346 u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
347 u32 snd_congestion; /**< snd_una_max when congestion is detected */
348 u32 tx_fifo_size; /**< Tx fifo size. Used to constrain cwnd */
349 tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
350 u8 cc_data[TCP_CC_DATA_SZ]; /**< Congestion control algo private data */
353 u32 rto; /**< Retransmission timeout */
354 u32 rto_boff; /**< Index for RTO backoff */
355 u32 srtt; /**< Smoothed RTT */
356 u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */
357 u32 rtt_seq; /**< Sequence number for tracked ACK */
358 f64 rtt_ts; /**< Timestamp for tracked ACK */
359 f64 mrtt_us; /**< High precision mrtt from tracked acks */
361 u32 psh_seq; /**< Add psh header for seg that includes this */
362 u32 next_node_index; /**< Can be used to control next node in output */
363 u32 next_node_opaque; /**< Opaque to pass to next node */
364 u32 limited_transmit; /**< snd_nxt when limited transmit starts */
365 u32 sw_if_index; /**< Interface for the connection */
367 /* Delivery rate estimation */
368 u64 delivered; /**< Total bytes delivered to peer */
369 u64 app_limited; /**< Delivered when app-limited detected */
370 f64 delivered_time; /**< Time last bytes were acked */
371 tcp_byte_tracker_t *bt; /**< Tx byte tracker */
373 u32 last_fib_check; /**< Last time we checked fib route for peer */
374 u16 mss; /**< Our max seg size that includes options */
378 struct _tcp_cc_algorithm
381 uword (*unformat_cfg) (unformat_input_t * input);
382 void (*rcv_ack) (tcp_connection_t * tc, tcp_rate_sample_t *rs);
383 void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack,
384 tcp_rate_sample_t *rs);
385 void (*congestion) (tcp_connection_t * tc);
386 void (*recovered) (tcp_connection_t * tc);
387 void (*init) (tcp_connection_t * tc);
388 void (*cleanup) (tcp_connection_t * tc);
392 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
393 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
394 #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY
395 #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY
396 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
397 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
398 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
399 #define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
400 #define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
401 #define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
402 #define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
403 #define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
404 #define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
406 #define tcp_in_cong_recovery(tc) ((tc)->flags & \
407 (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
410 tcp_cong_recovery_off (tcp_connection_t * tc)
412 tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
413 tcp_fastrecovery_first_off (tc);
416 #define tcp_zero_rwnd_sent(tc) (tc)->flags &= TCP_CONN_ZERO_RWND_SENT
417 #define tcp_zero_rwnd_sent_on(tc) (tc)->flags |= TCP_CONN_ZERO_RWND_SENT
418 #define tcp_zero_rwnd_sent_off(tc) (tc)->flags &= ~TCP_CONN_ZERO_RWND_SENT
420 typedef enum _tcp_error
422 #define tcp_error(n,s) TCP_ERROR_##n,
423 #include <vnet/tcp/tcp_error.def>
428 typedef struct _tcp_lookup_dispatch
431 } tcp_lookup_dispatch_t;
433 typedef struct tcp_worker_ctx_
435 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
439 /** worker timer wheel */
440 tw_timer_wheel_16t_2w_512sl_t timer_wheel;
442 /** tx buffer free list */
445 /** tx frames for tcp 4/6 output nodes */
446 vlib_frame_t *tx_frames[2];
448 /** tx frames for ip 4/6 lookup nodes */
449 vlib_frame_t *ip_lookup_tx_frames[2];
451 /** vector of connections needing fast rxt */
452 u32 *pending_fast_rxt;
454 /** vector of connections now doing fast rxt */
455 u32 *ongoing_fast_rxt;
457 /** vector of connections that will do fast rxt */
458 u32 *postponed_fast_rxt;
460 /** vector of pending ack dequeues */
461 u32 *pending_deq_acked;
463 /** vector of pending acks */
466 /** vector of pending disconnect notifications */
467 u32 *pending_disconnects;
469 /** convenience pointer to this thread's vlib main */
472 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
474 /** cached 'on the wire' options for bursts */
479 typedef struct tcp_iss_seed_
485 typedef struct _tcp_main
487 /* Per-worker thread tcp connection pools */
488 tcp_connection_t **connections;
490 /* Pool of listeners. */
491 tcp_connection_t *listener_pool;
493 /** Dispatch table by state and flags */
494 tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64];
496 u8 log2_tstamp_clocks_per_tick;
497 f64 tstamp_ticks_per_clock;
499 /** per-worker context */
500 tcp_worker_ctx_t *wrk_ctx;
502 /* Pool of half-open connections on which we've sent a SYN */
503 tcp_connection_t *half_open_connections;
504 clib_spinlock_t half_open_lock;
506 /** vlib buffer size */
507 u32 bytes_per_buffer;
509 /* Seed used to generate random iss */
510 tcp_iss_seed_t iss_seed;
512 /* Congestion control algorithms registered */
513 tcp_cc_algorithm_t *cc_algos;
515 /** Hash table of cc algorithms by name */
516 uword *cc_algo_by_name;
518 /** Last cc algo registered */
519 tcp_cc_algorithm_type_e cc_last_type;
525 /* Flag that indicates if stack is on or off */
528 /** Max rx fifo size for a session. It is used in to compute the
529 * rfc 7323 window scaling factor */
532 /** Default MTU to be used when establishing connections */
535 /** Number of preallocated connections */
536 u32 preallocated_connections;
537 u32 preallocated_half_open_connections;
539 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
540 ip4_address_t *ip4_src_addresses;
541 u32 last_v4_address_rotor;
542 u32 last_v6_address_rotor;
543 ip6_address_t *ip6_src_addresses;
545 /** Enable tx pacing for new connections */
551 /** fault-injection */
552 f64 buffer_fail_fraction;
554 /** Default congestion control algorithm type */
555 tcp_cc_algorithm_type_e cc_algo;
558 extern tcp_main_t tcp_main;
559 extern vlib_node_registration_t tcp4_input_node;
560 extern vlib_node_registration_t tcp6_input_node;
561 extern vlib_node_registration_t tcp4_output_node;
562 extern vlib_node_registration_t tcp6_output_node;
563 extern vlib_node_registration_t tcp4_established_node;
564 extern vlib_node_registration_t tcp6_established_node;
565 extern vlib_node_registration_t tcp4_syn_sent_node;
566 extern vlib_node_registration_t tcp6_syn_sent_node;
567 extern vlib_node_registration_t tcp4_rcv_process_node;
568 extern vlib_node_registration_t tcp6_rcv_process_node;
569 extern vlib_node_registration_t tcp4_listen_node;
570 extern vlib_node_registration_t tcp6_listen_node;
572 always_inline tcp_main_t *
578 always_inline tcp_worker_ctx_t *
579 tcp_get_worker (u32 thread_index)
581 return &tcp_main.wrk_ctx[thread_index];
584 always_inline tcp_header_t *
585 tcp_buffer_hdr (vlib_buffer_t * b)
587 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
588 return (tcp_header_t *) (b->data + b->current_data
589 + vnet_buffer (b)->tcp.hdr_offset);
592 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
593 #define tcp_trajectory_add_start(b, start) \
595 (*vlib_buffer_trace_trajectory_cb) (b, start); \
598 #define tcp_trajectory_add_start(b, start)
601 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
603 void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
605 always_inline tcp_connection_t *
606 tcp_connection_get (u32 conn_index, u32 thread_index)
609 (pool_is_free_index (tcp_main.connections[thread_index], conn_index)))
611 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
614 always_inline tcp_connection_t *
615 tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
617 if (tcp_main.connections[thread_index] == 0)
619 if (pool_is_free_index (tcp_main.connections[thread_index], conn_index))
621 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
624 always_inline tcp_connection_t *
625 tcp_get_connection_from_transport (transport_connection_t * tconn)
627 return (tcp_connection_t *) tconn;
631 tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
634 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
637 void tcp_connection_close (tcp_connection_t * tc);
638 void tcp_connection_cleanup (tcp_connection_t * tc);
639 void tcp_connection_del (tcp_connection_t * tc);
640 int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
641 tcp_connection_t *tcp_connection_alloc (u8 thread_index);
642 void tcp_connection_free (tcp_connection_t * tc);
643 void tcp_connection_reset (tcp_connection_t * tc);
644 int tcp_configure_v4_source_address_range (vlib_main_t * vm,
645 ip4_address_t * start,
646 ip4_address_t * end, u32 table_id);
647 int tcp_configure_v6_source_address_range (vlib_main_t * vm,
648 ip6_address_t * start,
649 ip6_address_t * end, u32 table_id);
650 void tcp_api_reference (void);
651 u8 *format_tcp_connection (u8 * s, va_list * args);
653 always_inline tcp_connection_t *
654 tcp_listener_get (u32 tli)
656 return pool_elt_at_index (tcp_main.listener_pool, tli);
659 always_inline tcp_connection_t *
660 tcp_half_open_connection_get (u32 conn_index)
662 tcp_connection_t *tc = 0;
663 clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
664 if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
665 tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
666 clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
670 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
671 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
672 void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
673 u32 thread_index, u8 is_ip4);
674 void tcp_send_reset (tcp_connection_t * tc);
675 void tcp_send_syn (tcp_connection_t * tc);
676 void tcp_send_synack (tcp_connection_t * tc);
677 void tcp_send_fin (tcp_connection_t * tc);
678 void tcp_init_mss (tcp_connection_t * tc);
679 void tcp_update_burst_snd_vars (tcp_connection_t * tc);
680 void tcp_update_rto (tcp_connection_t * tc);
681 void tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4);
682 void tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk);
683 void tcp_program_fastretransmit (tcp_worker_ctx_t * wrk,
684 tcp_connection_t * tc);
685 void tcp_do_fastretransmits (tcp_worker_ctx_t * wrk);
687 void tcp_program_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
688 void tcp_program_dupack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
689 void tcp_send_acks (tcp_worker_ctx_t * wrk);
690 void tcp_send_window_update_ack (tcp_connection_t * tc);
697 * Byte tracker initialize
699 * @param tc connection for which the byte tracker should be allocated and
702 void tcp_bt_init (tcp_connection_t * tc);
704 * Byte tracker cleanup
706 * @param tc connection for which the byte tracker should be cleaned up
708 void tcp_bt_cleanup (tcp_connection_t * tc);
710 * Flush byte tracker samples
712 * @param tc tcp connection for which samples should be flushed
714 void tcp_bt_flush_samples (tcp_connection_t * tc);
716 * Track a tcp tx burst
718 * @param tc tcp connection
720 void tcp_bt_track_tx (tcp_connection_t * tc);
722 * Track a tcp retransmission
724 * @param tc tcp connection
725 * @param start start sequence number
726 * @param end end sequence number
728 void tcp_bt_track_rxt (tcp_connection_t * tc, u32 start, u32 end);
730 * Generate a delivery rate sample from recently acked bytes
732 * @param tc tcp connection
733 * @param rs resulting rate sample
735 void tcp_bt_sample_delivery_rate (tcp_connection_t * tc,
736 tcp_rate_sample_t * rs);
738 * Check if sample to be generated is app limited
740 * @param tc tcp connection
742 void tcp_bt_check_app_limited (tcp_connection_t * tc);
744 * Check if the byte tracker is in sane state
746 * Should be used only for testing
748 * @param bt byte tracker
750 int tcp_bt_is_sane (tcp_byte_tracker_t * bt);
753 tcp_end_seq (tcp_header_t * th, u32 len)
755 return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len;
758 /* Modulo arithmetic for TCP sequence numbers */
759 #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0)
760 #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0)
761 #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0)
762 #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0)
763 #define seq_max(_s1, _s2) (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
765 /* Modulo arithmetic for timestamps */
766 #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
767 #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
770 * Our estimate of the number of bytes that have left the network
773 tcp_bytes_out (const tcp_connection_t * tc)
775 if (tcp_opts_sack_permitted (&tc->rcv_opts))
776 return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
778 return tc->rcv_dupacks * tc->snd_mss;
782 * Our estimate of the number of bytes in flight (pipe size)
785 tcp_flight_size (const tcp_connection_t * tc)
789 flight_size = (int) (tc->snd_nxt - tc->snd_una) - tcp_bytes_out (tc)
796 ("Negative: %u %u %u dupacks %u sacked bytes %u flags %d",
797 tc->snd_una_max - tc->snd_una, tcp_bytes_out (tc),
798 tc->snd_rxt_bytes, tc->rcv_dupacks, tc->sack_sb.sacked_bytes,
807 * Initial cwnd as per RFC5681
810 tcp_initial_cwnd (const tcp_connection_t * tc)
812 if (tc->snd_mss > 2190)
813 return 2 * tc->snd_mss;
814 else if (tc->snd_mss > 1095)
815 return 3 * tc->snd_mss;
817 return 4 * tc->snd_mss;
821 * Accumulate acked bytes for cwnd increase
823 * Once threshold bytes are accumulated, snd_mss bytes are added
827 tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
829 tc->cwnd_acc_bytes += bytes;
830 if (tc->cwnd_acc_bytes >= thresh)
832 u32 inc = tc->cwnd_acc_bytes / thresh;
833 tc->cwnd_acc_bytes -= inc * thresh;
834 tc->cwnd += inc * tc->snd_mss;
835 tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
840 tcp_loss_wnd (const tcp_connection_t * tc)
846 tcp_available_snd_wnd (const tcp_connection_t * tc)
848 return clib_min (tc->cwnd, tc->snd_wnd);
852 tcp_available_output_snd_space (const tcp_connection_t * tc)
854 u32 available_wnd = tcp_available_snd_wnd (tc);
855 int flight_size = (int) (tc->snd_nxt - tc->snd_una);
857 if (available_wnd <= flight_size)
860 return available_wnd - flight_size;
864 * Estimate of how many bytes we can still push into the network
867 tcp_available_cc_snd_space (const tcp_connection_t * tc)
869 u32 available_wnd = tcp_available_snd_wnd (tc);
870 u32 flight_size = tcp_flight_size (tc);
872 if (available_wnd <= flight_size)
875 return available_wnd - flight_size;
879 tcp_is_lost_fin (tcp_connection_t * tc)
881 if ((tc->flags & TCP_CONN_FINSNT) && tc->snd_una_max - tc->snd_una == 1)
886 u32 tcp_snd_space (tcp_connection_t * tc);
887 int tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk,
888 tcp_connection_t * tc);
889 int tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk,
890 tcp_connection_t * tc, u32 burst_size);
891 int tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
893 int tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
895 void tcp_cc_init_congestion (tcp_connection_t * tc);
896 void tcp_cc_fastrecovery_exit (tcp_connection_t * tc);
898 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
900 /* Made public for unit testing only */
901 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
902 u32 tcp_sack_list_bytes (tcp_connection_t * tc);
907 return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
911 tcp_time_now_w_thread (u32 thread_index)
913 return tcp_main.wrk_ctx[thread_index].time_now;
917 tcp_time_now_us (u32 thread_index)
919 return transport_time_now (thread_index);
923 tcp_set_time_now (tcp_worker_ctx_t * wrk)
925 wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
926 return wrk->time_now;
929 u32 tcp_session_push_header (transport_connection_t * tconn,
932 void tcp_connection_timers_init (tcp_connection_t * tc);
933 void tcp_connection_timers_reset (tcp_connection_t * tc);
934 void tcp_init_snd_vars (tcp_connection_t * tc);
935 void tcp_connection_init_vars (tcp_connection_t * tc);
936 void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
937 void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
941 tcp_cc_rcv_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
943 tc->cc_algo->rcv_ack (tc, rs);
944 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
948 tcp_cc_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
949 tcp_rate_sample_t * rs)
951 tc->cc_algo->rcv_cong_ack (tc, ack_type, rs);
955 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
957 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
958 ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
959 tc->timers[timer_id] =
960 tw_timer_start_16t_2w_512sl (&tcp_main.
961 wrk_ctx[tc->c_thread_index].timer_wheel,
962 tc->c_c_index, timer_id, interval);
966 tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
968 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
969 if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
972 tw_timer_stop_16t_2w_512sl (&tcp_main.
973 wrk_ctx[tc->c_thread_index].timer_wheel,
974 tc->timers[timer_id]);
975 tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
979 tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
981 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
982 if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
983 tw_timer_update_16t_2w_512sl (&tcp_main.
984 wrk_ctx[tc->c_thread_index].timer_wheel,
985 tc->timers[timer_id], interval);
987 tc->timers[timer_id] =
988 tw_timer_start_16t_2w_512sl (&tcp_main.
989 wrk_ctx[tc->c_thread_index].timer_wheel,
990 tc->c_c_index, timer_id, interval);
994 tcp_retransmit_timer_set (tcp_connection_t * tc)
996 ASSERT (tc->snd_una != tc->snd_una_max);
997 tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
998 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1002 tcp_retransmit_timer_reset (tcp_connection_t * tc)
1004 tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
1008 tcp_retransmit_timer_force_update (tcp_connection_t * tc)
1010 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1011 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1015 tcp_persist_timer_set (tcp_connection_t * tc)
1017 /* Reuse RTO. It's backed off in handler */
1018 tcp_timer_set (tc, TCP_TIMER_PERSIST,
1019 clib_max (tc->rto * TCP_TO_TIMER_TICK,
1020 TCP_TIMER_PERSIST_MIN));
1024 tcp_persist_timer_update (tcp_connection_t * tc)
1026 tcp_timer_update (tc, TCP_TIMER_PERSIST,
1027 clib_max (tc->rto * TCP_TO_TIMER_TICK,
1028 TCP_TIMER_PERSIST_MIN));
1032 tcp_persist_timer_reset (tcp_connection_t * tc)
1034 tcp_timer_reset (tc, TCP_TIMER_PERSIST);
1038 tcp_retransmit_timer_update (tcp_connection_t * tc)
1040 if (tc->snd_una == tc->snd_nxt)
1042 tcp_retransmit_timer_reset (tc);
1043 if (tc->snd_wnd < tc->snd_mss)
1044 tcp_persist_timer_update (tc);
1047 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1048 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1052 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
1054 return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
1057 #define tcp_validate_txf_size(_tc, _a) \
1058 ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
1059 || transport_max_tx_dequeue (&_tc->connection) >= _a)
1061 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
1062 u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
1065 * Register exiting cc algo type
1067 void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
1068 const tcp_cc_algorithm_t * vft);
1071 * Register new cc algo type
1073 tcp_cc_algorithm_type_e tcp_cc_algo_new_type (const tcp_cc_algorithm_t * vft);
1074 tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
1076 static inline void *
1077 tcp_cc_data (tcp_connection_t * tc)
1079 return (void *) tc->cc_data;
1082 void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1083 tcp_rate_sample_t * rs);
1086 * Push TCP header to buffer
1088 * @param vm - vlib_main
1089 * @param b - buffer to write the header to
1090 * @param sp_net - source port net order
1091 * @param dp_net - destination port net order
1092 * @param seq - sequence number net order
1093 * @param ack - ack number net order
1094 * @param tcp_hdr_opts_len - header and options length in bytes
1095 * @param flags - header flags
1096 * @param wnd - window size
1098 * @return - pointer to start of TCP header
1100 always_inline void *
1101 vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq,
1102 u32 ack, u8 tcp_hdr_opts_len, u8 flags,
1107 th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len);
1111 th->seq_number = seq;
1112 th->ack_number = ack;
1113 th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4;
1117 th->urgent_pointer = 0;
1122 * Push TCP header to buffer
1124 * @param b - buffer to write the header to
1125 * @param sp_net - source port net order
1126 * @param dp_net - destination port net order
1127 * @param seq - sequence number host order
1128 * @param ack - ack number host order
1129 * @param tcp_hdr_opts_len - header and options length in bytes
1130 * @param flags - header flags
1131 * @param wnd - window size
1133 * @return - pointer to start of TCP header
1135 always_inline void *
1136 vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq,
1137 u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
1139 return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net,
1140 clib_host_to_net_u32 (seq),
1141 clib_host_to_net_u32 (ack),
1142 tcp_hdr_opts_len, flags,
1143 clib_host_to_net_u16 (wnd));
1146 #endif /* _vnet_tcp_h_ */
1149 * fd.io coding-style-patch-verification: ON
1152 * eval: (c-set-style "gnu")