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 last_lost_bytes; /**< Number of bytes last lost */
187 u32 cur_rxt_hole; /**< Retransmitting from this hole */
189 #if TCP_SCOREBOARD_TRACE
190 scoreboard_trace_elt_t *trace;
195 #if TCP_SCOREBOARD_TRACE
196 #define tcp_scoreboard_trace_add(_tc, _ack) \
198 static u64 _group = 0; \
199 sack_scoreboard_t *_sb = &_tc->sack_sb; \
200 sack_block_t *_sack, *_sacks; \
201 scoreboard_trace_elt_t *_elt; \
204 _sacks = _tc->rcv_opts.sacks; \
205 for (i = 0; i < vec_len (_sacks); i++) \
207 _sack = &_sacks[i]; \
208 vec_add2 (_sb->trace, _elt, 1); \
209 _elt->start = _sack->start; \
210 _elt->end = _sack->end; \
211 _elt->ack = _elt->end == _ack ? _ack : 0; \
212 _elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0; \
213 _elt->group = _group; \
217 #define tcp_scoreboard_trace_add(_tc, _ack)
220 sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
221 sack_scoreboard_hole_t *
222 start, u8 have_sent_1_smss,
225 sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
228 sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
229 sack_scoreboard_hole_t * hole);
230 sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
231 sack_scoreboard_hole_t * hole);
232 sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
233 sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
234 void scoreboard_clear (sack_scoreboard_t * sb);
235 void scoreboard_init (sack_scoreboard_t * sb);
236 u8 *format_tcp_scoreboard (u8 * s, va_list * args);
238 #define TCP_BTS_INVALID_INDEX ((u32)~0)
240 typedef enum tcp_bts_flags_
243 TCP_BTS_IS_APP_LIMITED = 1 << 1,
244 } __clib_packed tcp_bts_flags_t;
246 typedef struct tcp_bt_sample_
248 u32 next; /**< Next sample index in list */
249 u32 prev; /**< Previous sample index in list */
250 u32 min_seq; /**< Min seq number in sample */
251 u32 max_seq; /**< Max seq number. Set for rxt samples */
252 u64 delivered; /**< Total delivered bytes for sample */
253 f64 delivered_time; /**< Delivered time when sample taken */
254 f64 tx_time; /**< Transmit time for the burst */
255 u64 tx_rate; /**< Tx pacing rate */
256 tcp_bts_flags_t flags; /**< Sample flag */
259 typedef struct tcp_rate_sample_
261 u64 prior_delivered; /**< Delivered of sample used for rate, i.e.,
262 total bytes delivered at prior_time */
263 f64 prior_time; /**< Delivered time of sample used for rate */
264 f64 interval_time; /**< Time to ack the bytes delivered */
265 f64 rtt_time; /**< RTT for sample */
266 u64 tx_rate; /**< Tx pacing rate */
267 u32 delivered; /**< Bytes delivered in interval_time */
268 u32 acked_and_sacked; /**< Bytes acked + sacked now */
269 u32 lost; /**< Bytes lost now */
270 tcp_bts_flags_t flags; /**< Rate sample flags from bt sample */
273 typedef struct tcp_byte_tracker_
275 tcp_bt_sample_t *samples; /**< Pool of samples */
276 rb_tree_t sample_lookup; /**< Rbtree for sample lookup by min_seq */
277 u32 head; /**< Head of samples linked list */
278 u32 tail; /**< Tail of samples linked list */
279 u32 last_ooo; /**< Cached last ooo sample */
280 } tcp_byte_tracker_t;
282 typedef enum _tcp_cc_algorithm_type
286 TCP_CC_LAST = TCP_CC_CUBIC
287 } tcp_cc_algorithm_type_e;
289 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
291 typedef enum _tcp_cc_ack_t
298 typedef enum tcp_cc_event_
304 * As per RFC4898 tcpEStatsStackSoftErrors
306 typedef struct tcp_errors_
308 u32 below_data_wnd; /**< All data in seg is below snd_una */
309 u32 above_data_wnd; /**< Some data in segment is above snd_wnd */
310 u32 below_ack_wnd; /**< Acks for data below snd_una */
311 u32 above_ack_wnd; /**< Acks for data not sent */
314 typedef struct _tcp_connection
316 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
317 transport_connection_t connection; /**< Common transport data. First! */
319 u8 state; /**< TCP state as per tcp_state_t */
320 u16 flags; /**< Connection flags (see tcp_conn_flags_e) */
321 u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */
323 u64 segs_in; /** RFC4022/4898 tcpHCInSegs/tcpEStatsPerfSegsIn */
324 u64 bytes_in; /** RFC4898 tcpEStatsPerfHCDataOctetsIn */
325 u64 segs_out; /** RFC4898 tcpEStatsPerfSegsOut */
326 u64 bytes_out; /** RFC4898 tcpEStatsPerfHCDataOctetsOut */
328 /** Send sequence variables RFC793 */
329 u32 snd_una; /**< oldest unacknowledged sequence number */
330 u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/
331 u32 snd_wnd; /**< send window */
332 u32 snd_wl1; /**< seq number used for last snd.wnd update */
333 u32 snd_wl2; /**< ack number used for last snd.wnd update */
334 u32 snd_nxt; /**< next seq number to be sent */
335 u16 snd_mss; /**< Effective send max seg (data) size */
337 u64 data_segs_in; /** RFC4898 tcpEStatsPerfDataSegsIn */
338 u64 data_segs_out; /** RFC4898 tcpEStatsPerfDataSegsOut */
340 /** Receive sequence variables RFC793 */
341 u32 rcv_nxt; /**< next sequence number expected */
342 u32 rcv_wnd; /**< receive window we expect */
344 u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */
345 u32 iss; /**< initial sent sequence */
346 u32 irs; /**< initial remote sequence */
349 u8 snd_opts_len; /**< Tx options len */
350 u8 rcv_wscale; /**< Window scale to advertise to peer */
351 u8 snd_wscale; /**< Window scale to use when sending */
352 u32 tsval_recent; /**< Last timestamp received */
353 u32 tsval_recent_age; /**< When last updated tstamp_recent*/
354 tcp_options_t snd_opts; /**< Tx options for connection */
355 tcp_options_t rcv_opts; /**< Rx options for connection */
357 sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */
358 u8 snd_sack_pos; /**< Position in vec of first block to send */
359 sack_block_t *snd_sacks_fl; /**< Vector for building new list */
360 sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */
362 u16 rcv_dupacks; /**< Number of recent DUPACKs received */
363 u32 dupacks_in; /**< RFC4898 tcpEStatsStackDupAcksIn*/
364 u8 pending_dupacks; /**< Number of DUPACKs to be sent */
365 u32 dupacks_out; /**< RFC4898 tcpEStatsPathDupAcksOut */
367 /* Congestion control */
368 u32 cwnd; /**< Congestion window */
369 u32 cwnd_acc_bytes; /**< Bytes accumulated for cwnd increment */
370 u32 ssthresh; /**< Slow-start threshold */
371 u32 prev_ssthresh; /**< ssthresh before congestion */
372 u32 prev_cwnd; /**< ssthresh before congestion */
373 u32 bytes_acked; /**< Bytes acknowledged by current segment */
374 u32 burst_acked; /**< Bytes acknowledged in current burst */
375 u32 snd_rxt_bytes; /**< Retransmitted bytes */
376 u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
377 u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
378 u32 snd_congestion; /**< snd_una_max when congestion is detected */
379 u32 tx_fifo_size; /**< Tx fifo size. Used to constrain cwnd */
380 tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
381 u8 cc_data[TCP_CC_DATA_SZ]; /**< Congestion control algo private data */
383 u32 fr_occurences; /**< fast-retransmit occurrences RFC4898
384 tcpEStatsStackFastRetran */
385 u32 tr_occurences; /**< timer-retransmit occurrences */
386 u64 bytes_retrans; /**< RFC4898 tcpEStatsPerfOctetsRetrans */
387 u64 segs_retrans; /**< RFC4898 tcpEStatsPerfSegsRetrans*/
390 u32 rto; /**< Retransmission timeout */
391 u32 rto_boff; /**< Index for RTO backoff */
392 u32 srtt; /**< Smoothed RTT */
393 u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */
394 u32 rtt_seq; /**< Sequence number for tracked ACK */
395 f64 rtt_ts; /**< Timestamp for tracked ACK */
396 f64 mrtt_us; /**< High precision mrtt from tracked acks */
398 u32 psh_seq; /**< Add psh header for seg that includes this */
399 u32 next_node_index; /**< Can be used to control next node in output */
400 u32 next_node_opaque; /**< Opaque to pass to next node */
401 u32 limited_transmit; /**< snd_nxt when limited transmit starts */
402 u32 sw_if_index; /**< Interface for the connection */
404 /* Delivery rate estimation */
405 u64 delivered; /**< Total bytes delivered to peer */
406 u64 app_limited; /**< Delivered when app-limited detected */
407 f64 delivered_time; /**< Time last bytes were acked */
408 tcp_byte_tracker_t *bt; /**< Tx byte tracker */
410 tcp_errors_t errors; /**< Soft connection errors */
412 f64 start_ts; /**< Timestamp when connection initialized */
413 u32 last_fib_check; /**< Last time we checked fib route for peer */
414 u16 mss; /**< Our max seg size that includes options */
415 u32 timestamp_delta; /**< Offset for timestamp */
419 struct _tcp_cc_algorithm
422 uword (*unformat_cfg) (unformat_input_t * input);
423 void (*init) (tcp_connection_t * tc);
424 void (*cleanup) (tcp_connection_t * tc);
425 void (*rcv_ack) (tcp_connection_t * tc, tcp_rate_sample_t *rs);
426 void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack,
427 tcp_rate_sample_t *rs);
428 void (*congestion) (tcp_connection_t * tc);
429 void (*loss) (tcp_connection_t * tc);
430 void (*recovered) (tcp_connection_t * tc);
431 void (*undo_recovery) (tcp_connection_t * tc);
432 void (*event) (tcp_connection_t *tc, tcp_cc_event_t evt);
436 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
437 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
438 #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY
439 #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY
440 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
441 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
442 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
443 #define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
444 #define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
445 #define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
446 #define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
447 #define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
448 #define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
450 #define tcp_in_cong_recovery(tc) ((tc)->flags & \
451 (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
454 tcp_cong_recovery_off (tcp_connection_t * tc)
456 tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
457 tcp_fastrecovery_first_off (tc);
460 #define tcp_zero_rwnd_sent(tc) ((tc)->flags & TCP_CONN_ZERO_RWND_SENT)
461 #define tcp_zero_rwnd_sent_on(tc) (tc)->flags |= TCP_CONN_ZERO_RWND_SENT
462 #define tcp_zero_rwnd_sent_off(tc) (tc)->flags &= ~TCP_CONN_ZERO_RWND_SENT
464 typedef enum _tcp_error
466 #define tcp_error(n,s) TCP_ERROR_##n,
467 #include <vnet/tcp/tcp_error.def>
472 typedef struct _tcp_lookup_dispatch
475 } tcp_lookup_dispatch_t;
477 typedef struct tcp_worker_ctx_
479 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
483 /** worker timer wheel */
484 tw_timer_wheel_16t_2w_512sl_t timer_wheel;
486 /** tx buffer free list */
489 /** tx frames for tcp 4/6 output nodes */
490 vlib_frame_t *tx_frames[2];
492 /** tx frames for ip 4/6 lookup nodes */
493 vlib_frame_t *ip_lookup_tx_frames[2];
495 /** vector of pending ack dequeues */
496 u32 *pending_deq_acked;
498 /** vector of pending disconnect notifications */
499 u32 *pending_disconnects;
501 /** convenience pointer to this thread's vlib main */
504 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
506 /** cached 'on the wire' options for bursts */
511 typedef struct tcp_iss_seed_
517 typedef struct _tcp_main
519 /* Per-worker thread tcp connection pools */
520 tcp_connection_t **connections;
522 /* Pool of listeners. */
523 tcp_connection_t *listener_pool;
525 /** Dispatch table by state and flags */
526 tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64];
528 u8 log2_tstamp_clocks_per_tick;
529 f64 tstamp_ticks_per_clock;
531 /** per-worker context */
532 tcp_worker_ctx_t *wrk_ctx;
534 /* Pool of half-open connections on which we've sent a SYN */
535 tcp_connection_t *half_open_connections;
536 clib_spinlock_t half_open_lock;
538 /** vlib buffer size */
539 u32 bytes_per_buffer;
541 /* Seed used to generate random iss */
542 tcp_iss_seed_t iss_seed;
544 /* Congestion control algorithms registered */
545 tcp_cc_algorithm_t *cc_algos;
547 /** Hash table of cc algorithms by name */
548 uword *cc_algo_by_name;
550 /** Last cc algo registered */
551 tcp_cc_algorithm_type_e cc_last_type;
557 /* Flag that indicates if stack is on or off */
560 /** Max rx fifo size for a session. It is used in to compute the
561 * rfc 7323 window scaling factor */
564 /** Default MTU to be used when establishing connections */
567 /** Initial CWND multiplier, which multiplies MSS to determine initial CWND.
568 * Set 0 to determine the initial CWND by another way */
569 u16 initial_cwnd_multiplier;
571 /** Number of preallocated connections */
572 u32 preallocated_connections;
573 u32 preallocated_half_open_connections;
575 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
576 ip4_address_t *ip4_src_addresses;
577 u32 last_v4_address_rotor;
578 u32 last_v6_address_rotor;
579 ip6_address_t *ip6_src_addresses;
581 /** Enable tx pacing for new connections */
587 /** fault-injection */
588 f64 buffer_fail_fraction;
590 /** Default congestion control algorithm type */
591 tcp_cc_algorithm_type_e cc_algo;
594 extern tcp_main_t tcp_main;
595 extern vlib_node_registration_t tcp4_input_node;
596 extern vlib_node_registration_t tcp6_input_node;
597 extern vlib_node_registration_t tcp4_output_node;
598 extern vlib_node_registration_t tcp6_output_node;
599 extern vlib_node_registration_t tcp4_established_node;
600 extern vlib_node_registration_t tcp6_established_node;
601 extern vlib_node_registration_t tcp4_syn_sent_node;
602 extern vlib_node_registration_t tcp6_syn_sent_node;
603 extern vlib_node_registration_t tcp4_rcv_process_node;
604 extern vlib_node_registration_t tcp6_rcv_process_node;
605 extern vlib_node_registration_t tcp4_listen_node;
606 extern vlib_node_registration_t tcp6_listen_node;
608 #define tcp_node_index(node_id, is_ip4) \
609 ((is_ip4) ? tcp4_##node_id##_node.index : tcp6_##node_id##_node.index)
611 always_inline tcp_main_t *
617 always_inline tcp_worker_ctx_t *
618 tcp_get_worker (u32 thread_index)
620 return &tcp_main.wrk_ctx[thread_index];
623 always_inline tcp_header_t *
624 tcp_buffer_hdr (vlib_buffer_t * b)
626 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
627 return (tcp_header_t *) (b->data + b->current_data
628 + vnet_buffer (b)->tcp.hdr_offset);
631 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
632 #define tcp_trajectory_add_start(b, start) \
634 (*vlib_buffer_trace_trajectory_cb) (b, start); \
637 #define tcp_trajectory_add_start(b, start)
640 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
642 void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
644 always_inline tcp_connection_t *
645 tcp_connection_get (u32 conn_index, u32 thread_index)
648 (pool_is_free_index (tcp_main.connections[thread_index], conn_index)))
650 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
653 always_inline tcp_connection_t *
654 tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
656 if (tcp_main.connections[thread_index] == 0)
658 if (pool_is_free_index (tcp_main.connections[thread_index], conn_index))
660 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
663 always_inline tcp_connection_t *
664 tcp_get_connection_from_transport (transport_connection_t * tconn)
666 return (tcp_connection_t *) tconn;
670 tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
673 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
676 void tcp_connection_close (tcp_connection_t * tc);
677 void tcp_connection_cleanup (tcp_connection_t * tc);
678 void tcp_connection_del (tcp_connection_t * tc);
679 int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
680 tcp_connection_t *tcp_connection_alloc (u8 thread_index);
681 void tcp_connection_free (tcp_connection_t * tc);
682 void tcp_connection_reset (tcp_connection_t * tc);
683 int tcp_configure_v4_source_address_range (vlib_main_t * vm,
684 ip4_address_t * start,
685 ip4_address_t * end, u32 table_id);
686 int tcp_configure_v6_source_address_range (vlib_main_t * vm,
687 ip6_address_t * start,
688 ip6_address_t * end, u32 table_id);
689 void tcp_api_reference (void);
690 u8 *format_tcp_connection (u8 * s, va_list * args);
692 always_inline tcp_connection_t *
693 tcp_listener_get (u32 tli)
695 return pool_elt_at_index (tcp_main.listener_pool, tli);
698 always_inline tcp_connection_t *
699 tcp_half_open_connection_get (u32 conn_index)
701 tcp_connection_t *tc = 0;
702 clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
703 if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
704 tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
705 clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
709 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
710 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
711 void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
712 u32 thread_index, u8 is_ip4);
713 void tcp_send_reset (tcp_connection_t * tc);
714 void tcp_send_syn (tcp_connection_t * tc);
715 void tcp_send_synack (tcp_connection_t * tc);
716 void tcp_send_fin (tcp_connection_t * tc);
717 void tcp_init_mss (tcp_connection_t * tc);
718 void tcp_update_burst_snd_vars (tcp_connection_t * tc);
719 void tcp_update_rto (tcp_connection_t * tc);
720 void tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4);
721 void tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk);
722 void tcp_send_window_update_ack (tcp_connection_t * tc);
724 void tcp_program_ack (tcp_connection_t * tc);
725 void tcp_program_dupack (tcp_connection_t * tc);
726 void tcp_program_fastretransmit (tcp_connection_t * tc);
733 * Byte tracker initialize
735 * @param tc connection for which the byte tracker should be allocated and
738 void tcp_bt_init (tcp_connection_t * tc);
740 * Byte tracker cleanup
742 * @param tc connection for which the byte tracker should be cleaned up
744 void tcp_bt_cleanup (tcp_connection_t * tc);
746 * Flush byte tracker samples
748 * @param tc tcp connection for which samples should be flushed
750 void tcp_bt_flush_samples (tcp_connection_t * tc);
752 * Track a tcp tx burst
754 * @param tc tcp connection
756 void tcp_bt_track_tx (tcp_connection_t * tc);
758 * Track a tcp retransmission
760 * @param tc tcp connection
761 * @param start start sequence number
762 * @param end end sequence number
764 void tcp_bt_track_rxt (tcp_connection_t * tc, u32 start, u32 end);
766 * Generate a delivery rate sample from recently acked bytes
768 * @param tc tcp connection
769 * @param rs resulting rate sample
771 void tcp_bt_sample_delivery_rate (tcp_connection_t * tc,
772 tcp_rate_sample_t * rs);
774 * Check if sample to be generated is app limited
776 * @param tc tcp connection
778 void tcp_bt_check_app_limited (tcp_connection_t * tc);
780 * Check if the byte tracker is in sane state
782 * Should be used only for testing
784 * @param bt byte tracker
786 int tcp_bt_is_sane (tcp_byte_tracker_t * bt);
789 tcp_end_seq (tcp_header_t * th, u32 len)
791 return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len;
794 /* Modulo arithmetic for TCP sequence numbers */
795 #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0)
796 #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0)
797 #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0)
798 #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0)
799 #define seq_max(_s1, _s2) (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
801 /* Modulo arithmetic for timestamps */
802 #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
803 #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
806 * Our estimate of the number of bytes that have left the network
809 tcp_bytes_out (const tcp_connection_t * tc)
811 if (tcp_opts_sack_permitted (&tc->rcv_opts))
812 return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
814 return tc->rcv_dupacks * tc->snd_mss;
818 * Our estimate of the number of bytes in flight (pipe size)
821 tcp_flight_size (const tcp_connection_t * tc)
825 flight_size = (int) (tc->snd_nxt - tc->snd_una) - tcp_bytes_out (tc)
832 ("Negative: %u %u %u dupacks %u sacked bytes %u flags %d",
833 tc->snd_una_max - tc->snd_una, tcp_bytes_out (tc),
834 tc->snd_rxt_bytes, tc->rcv_dupacks, tc->sack_sb.sacked_bytes,
843 * Initial cwnd as per RFC5681
846 tcp_initial_cwnd (const tcp_connection_t * tc)
848 if (tcp_main.initial_cwnd_multiplier > 0)
849 return tcp_main.initial_cwnd_multiplier * tc->snd_mss;
851 if (tc->snd_mss > 2190)
852 return 2 * tc->snd_mss;
853 else if (tc->snd_mss > 1095)
854 return 3 * tc->snd_mss;
856 return 4 * tc->snd_mss;
860 * Accumulate acked bytes for cwnd increase
862 * Once threshold bytes are accumulated, snd_mss bytes are added
866 tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
868 tc->cwnd_acc_bytes += bytes;
869 if (tc->cwnd_acc_bytes >= thresh)
871 u32 inc = tc->cwnd_acc_bytes / thresh;
872 tc->cwnd_acc_bytes -= inc * thresh;
873 tc->cwnd += inc * tc->snd_mss;
874 tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
879 tcp_loss_wnd (const tcp_connection_t * tc)
885 tcp_available_snd_wnd (const tcp_connection_t * tc)
887 return clib_min (tc->cwnd, tc->snd_wnd);
891 tcp_available_output_snd_space (const tcp_connection_t * tc)
893 u32 available_wnd = tcp_available_snd_wnd (tc);
894 int flight_size = (int) (tc->snd_nxt - tc->snd_una);
896 if (available_wnd <= flight_size)
899 return available_wnd - flight_size;
903 * Estimate of how many bytes we can still push into the network
906 tcp_available_cc_snd_space (const tcp_connection_t * tc)
908 u32 available_wnd = tcp_available_snd_wnd (tc);
909 u32 flight_size = tcp_flight_size (tc);
911 if (available_wnd <= flight_size)
914 return available_wnd - flight_size;
918 tcp_is_lost_fin (tcp_connection_t * tc)
920 if ((tc->flags & TCP_CONN_FINSNT) && tc->snd_una_max - tc->snd_una == 1)
925 u32 tcp_snd_space (tcp_connection_t * tc);
926 int tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk,
927 tcp_connection_t * tc);
928 int tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk,
929 tcp_connection_t * tc, u32 burst_size);
930 int tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
932 int tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
934 void tcp_cc_init_congestion (tcp_connection_t * tc);
935 void tcp_cc_fastrecovery_clear (tcp_connection_t * tc);
937 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
939 /* Made public for unit testing only */
940 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
941 u32 tcp_sack_list_bytes (tcp_connection_t * tc);
946 return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
950 tcp_time_now_w_thread (u32 thread_index)
952 return tcp_main.wrk_ctx[thread_index].time_now;
956 * Generate timestamp for tcp connection
959 tcp_tstamp (tcp_connection_t * tc)
961 return (tcp_main.wrk_ctx[tc->c_thread_index].time_now -
962 tc->timestamp_delta);
966 tcp_time_now_us (u32 thread_index)
968 return transport_time_now (thread_index);
972 tcp_set_time_now (tcp_worker_ctx_t * wrk)
974 wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
975 return wrk->time_now;
978 u32 tcp_session_push_header (transport_connection_t * tconn,
980 int tcp_session_custom_tx (void *conn, u32 max_burst_size);
982 void tcp_connection_timers_init (tcp_connection_t * tc);
983 void tcp_connection_timers_reset (tcp_connection_t * tc);
984 void tcp_init_snd_vars (tcp_connection_t * tc);
985 void tcp_connection_init_vars (tcp_connection_t * tc);
986 void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
987 void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
991 tcp_cc_rcv_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
993 tc->cc_algo->rcv_ack (tc, rs);
994 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
998 tcp_cc_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
999 tcp_rate_sample_t * rs)
1001 tc->cc_algo->rcv_cong_ack (tc, ack_type, rs);
1005 tcp_cc_loss (tcp_connection_t * tc)
1007 tc->cc_algo->loss (tc);
1011 tcp_cc_recovered (tcp_connection_t * tc)
1013 tc->cc_algo->recovered (tc);
1017 tcp_cc_undo_recovery (tcp_connection_t * tc)
1019 if (tc->cc_algo->undo_recovery)
1020 tc->cc_algo->undo_recovery (tc);
1024 tcp_cc_event (tcp_connection_t * tc, tcp_cc_event_t evt)
1026 if (tc->cc_algo->event)
1027 tc->cc_algo->event (tc, evt);
1031 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
1033 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1034 ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
1035 tc->timers[timer_id] =
1036 tw_timer_start_16t_2w_512sl (&tcp_main.
1037 wrk_ctx[tc->c_thread_index].timer_wheel,
1038 tc->c_c_index, timer_id, interval);
1042 tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
1044 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1045 if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
1048 tw_timer_stop_16t_2w_512sl (&tcp_main.
1049 wrk_ctx[tc->c_thread_index].timer_wheel,
1050 tc->timers[timer_id]);
1051 tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
1055 tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
1057 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1058 if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
1059 tw_timer_update_16t_2w_512sl (&tcp_main.
1060 wrk_ctx[tc->c_thread_index].timer_wheel,
1061 tc->timers[timer_id], interval);
1063 tc->timers[timer_id] =
1064 tw_timer_start_16t_2w_512sl (&tcp_main.
1065 wrk_ctx[tc->c_thread_index].timer_wheel,
1066 tc->c_c_index, timer_id, interval);
1070 tcp_retransmit_timer_set (tcp_connection_t * tc)
1072 ASSERT (tc->snd_una != tc->snd_una_max);
1073 tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
1074 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1078 tcp_retransmit_timer_reset (tcp_connection_t * tc)
1080 tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
1084 tcp_retransmit_timer_force_update (tcp_connection_t * tc)
1086 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1087 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1091 tcp_persist_timer_set (tcp_connection_t * tc)
1093 /* Reuse RTO. It's backed off in handler */
1094 tcp_timer_set (tc, TCP_TIMER_PERSIST,
1095 clib_max (tc->rto * TCP_TO_TIMER_TICK,
1096 TCP_TIMER_PERSIST_MIN));
1100 tcp_persist_timer_update (tcp_connection_t * tc)
1102 tcp_timer_update (tc, TCP_TIMER_PERSIST,
1103 clib_max (tc->rto * TCP_TO_TIMER_TICK,
1104 TCP_TIMER_PERSIST_MIN));
1108 tcp_persist_timer_reset (tcp_connection_t * tc)
1110 tcp_timer_reset (tc, TCP_TIMER_PERSIST);
1114 tcp_retransmit_timer_update (tcp_connection_t * tc)
1116 if (tc->snd_una == tc->snd_nxt)
1118 tcp_retransmit_timer_reset (tc);
1119 if (tc->snd_wnd < tc->snd_mss)
1120 tcp_persist_timer_update (tc);
1123 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1124 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1128 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
1130 return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
1133 #define tcp_validate_txf_size(_tc, _a) \
1134 ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
1135 || transport_max_tx_dequeue (&_tc->connection) >= _a)
1137 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
1138 u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
1141 * Register exiting cc algo type
1143 void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
1144 const tcp_cc_algorithm_t * vft);
1147 * Register new cc algo type
1149 tcp_cc_algorithm_type_e tcp_cc_algo_new_type (const tcp_cc_algorithm_t * vft);
1150 tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
1152 static inline void *
1153 tcp_cc_data (tcp_connection_t * tc)
1155 return (void *) tc->cc_data;
1158 void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1159 tcp_rate_sample_t * rs);
1162 * Push TCP header to buffer
1164 * @param vm - vlib_main
1165 * @param b - buffer to write the header to
1166 * @param sp_net - source port net order
1167 * @param dp_net - destination port net order
1168 * @param seq - sequence number net order
1169 * @param ack - ack number net order
1170 * @param tcp_hdr_opts_len - header and options length in bytes
1171 * @param flags - header flags
1172 * @param wnd - window size
1174 * @return - pointer to start of TCP header
1176 always_inline void *
1177 vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq,
1178 u32 ack, u8 tcp_hdr_opts_len, u8 flags,
1183 th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len);
1187 th->seq_number = seq;
1188 th->ack_number = ack;
1189 th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4;
1193 th->urgent_pointer = 0;
1198 * Push TCP header to buffer
1200 * @param b - buffer to write the header to
1201 * @param sp_net - source port net order
1202 * @param dp_net - destination port net order
1203 * @param seq - sequence number host order
1204 * @param ack - ack number host order
1205 * @param tcp_hdr_opts_len - header and options length in bytes
1206 * @param flags - header flags
1207 * @param wnd - window size
1209 * @return - pointer to start of TCP header
1211 always_inline void *
1212 vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq,
1213 u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
1215 return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net,
1216 clib_host_to_net_u32 (seq),
1217 clib_host_to_net_u32 (ack),
1218 tcp_hdr_opts_len, flags,
1219 clib_host_to_net_u16 (wnd));
1222 #endif /* _vnet_tcp_h_ */
1225 * fd.io coding-style-patch-verification: ON
1228 * eval: (c-set-style "gnu")